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_Cat; use Sem_Cat;
54 with Sem_Ch3; use Sem_Ch3;
55 with Sem_Ch8; use Sem_Ch8;
56 with Sem_Ch13; use Sem_Ch13;
57 with Sem_Eval; use Sem_Eval;
58 with Sem_Res; use Sem_Res;
59 with Sem_Type; use Sem_Type;
60 with Sem_Util; use Sem_Util;
61 with Sem_Warn; use Sem_Warn;
62 with Sinfo; use Sinfo;
63 with Snames; use Snames;
64 with Stand; use Stand;
65 with Targparm; use Targparm;
66 with Tbuild; use Tbuild;
67 with Ttypes; use Ttypes;
68 with Uintp; use Uintp;
69 with Urealp; use Urealp;
70 with Validsw; use Validsw;
72 package body Exp_Ch4 is
74 -----------------------
75 -- Local Subprograms --
76 -----------------------
78 procedure Binary_Op_Validity_Checks (N : Node_Id);
79 pragma Inline (Binary_Op_Validity_Checks);
80 -- Performs validity checks for a binary operator
82 procedure Build_Boolean_Array_Proc_Call
86 -- If a boolean array assignment can be done in place, build call to
87 -- corresponding library procedure.
89 procedure Displace_Allocator_Pointer (N : Node_Id);
90 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
91 -- Expand_Allocator_Expression. Allocating class-wide interface objects
92 -- this routine displaces the pointer to the allocated object to reference
93 -- the component referencing the corresponding secondary dispatch table.
95 procedure Expand_Allocator_Expression (N : Node_Id);
96 -- Subsidiary to Expand_N_Allocator, for the case when the expression
97 -- is a qualified expression or an aggregate.
99 procedure Expand_Array_Comparison (N : Node_Id);
100 -- This routine handles expansion of the comparison operators (N_Op_Lt,
101 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
102 -- code for these operators is similar, differing only in the details of
103 -- the actual comparison call that is made. Special processing (call a
106 function Expand_Array_Equality
111 Typ : Entity_Id) return Node_Id;
112 -- Expand an array equality into a call to a function implementing this
113 -- equality, and a call to it. Loc is the location for the generated nodes.
114 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
115 -- on which to attach bodies of local functions that are created in the
116 -- process. It is the responsibility of the caller to insert those bodies
117 -- at the right place. Nod provides the Sloc value for the generated code.
118 -- Normally the types used for the generated equality routine are taken
119 -- from Lhs and Rhs. However, in some situations of generated code, the
120 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
121 -- the type to be used for the formal parameters.
123 procedure Expand_Boolean_Operator (N : Node_Id);
124 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
125 -- case of array type arguments.
127 function Expand_Composite_Equality
132 Bodies : List_Id) return Node_Id;
133 -- Local recursive function used to expand equality for nested composite
134 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
135 -- to attach bodies of local functions that are created in the process.
136 -- This is the responsibility of the caller to insert those bodies at the
137 -- right place. Nod provides the Sloc value for generated code. Lhs and Rhs
138 -- are the left and right sides for the comparison, and Typ is the type of
139 -- the arrays to compare.
141 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id);
142 -- Routine to expand concatenation of a sequence of two or more operands
143 -- (in the list Operands) and replace node Cnode with the result of the
144 -- concatenation. The operands can be of any appropriate type, and can
145 -- include both arrays and singleton elements.
147 procedure Fixup_Universal_Fixed_Operation (N : Node_Id);
148 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
149 -- fixed. We do not have such a type at runtime, so the purpose of this
150 -- routine is to find the real type by looking up the tree. We also
151 -- determine if the operation must be rounded.
153 function Get_Allocator_Final_List
156 PtrT : Entity_Id) return Entity_Id;
157 -- If the designated type is controlled, build final_list expression for
158 -- created object. If context is an access parameter, create a local access
159 -- type to have a usable finalization list.
161 function Has_Inferable_Discriminants (N : Node_Id) return Boolean;
162 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
163 -- discriminants if it has a constrained nominal type, unless the object
164 -- is a component of an enclosing Unchecked_Union object that is subject
165 -- to a per-object constraint and the enclosing object lacks inferable
168 -- An expression of an Unchecked_Union type has inferable discriminants
169 -- if it is either a name of an object with inferable discriminants or a
170 -- qualified expression whose subtype mark denotes a constrained subtype.
172 procedure Insert_Dereference_Action (N : Node_Id);
173 -- N is an expression whose type is an access. When the type of the
174 -- associated storage pool is derived from Checked_Pool, generate a
175 -- call to the 'Dereference' primitive operation.
177 function Make_Array_Comparison_Op
179 Nod : Node_Id) return Node_Id;
180 -- Comparisons between arrays are expanded in line. This function produces
181 -- the body of the implementation of (a > b), where a and b are one-
182 -- dimensional arrays of some discrete type. The original node is then
183 -- expanded into the appropriate call to this function. Nod provides the
184 -- Sloc value for the generated code.
186 function Make_Boolean_Array_Op
188 N : Node_Id) return Node_Id;
189 -- Boolean operations on boolean arrays are expanded in line. This function
190 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
191 -- b). It is used only the normal case and not the packed case. The type
192 -- involved, Typ, is the Boolean array type, and the logical operations in
193 -- the body are simple boolean operations. Note that Typ is always a
194 -- constrained type (the caller has ensured this by using
195 -- Convert_To_Actual_Subtype if necessary).
197 procedure Rewrite_Comparison (N : Node_Id);
198 -- If N is the node for a comparison whose outcome can be determined at
199 -- compile time, then the node N can be rewritten with True or False. If
200 -- the outcome cannot be determined at compile time, the call has no
201 -- effect. If N is a type conversion, then this processing is applied to
202 -- its expression. If N is neither comparison nor a type conversion, the
203 -- call has no effect.
205 function Tagged_Membership (N : Node_Id) return Node_Id;
206 -- Construct the expression corresponding to the tagged membership test.
207 -- Deals with a second operand being (or not) a class-wide type.
209 function Safe_In_Place_Array_Op
212 Op2 : Node_Id) return Boolean;
213 -- In the context of an assignment, where the right-hand side is a boolean
214 -- operation on arrays, check whether operation can be performed in place.
216 procedure Unary_Op_Validity_Checks (N : Node_Id);
217 pragma Inline (Unary_Op_Validity_Checks);
218 -- Performs validity checks for a unary operator
220 -------------------------------
221 -- Binary_Op_Validity_Checks --
222 -------------------------------
224 procedure Binary_Op_Validity_Checks (N : Node_Id) is
226 if Validity_Checks_On and Validity_Check_Operands then
227 Ensure_Valid (Left_Opnd (N));
228 Ensure_Valid (Right_Opnd (N));
230 end Binary_Op_Validity_Checks;
232 ------------------------------------
233 -- Build_Boolean_Array_Proc_Call --
234 ------------------------------------
236 procedure Build_Boolean_Array_Proc_Call
241 Loc : constant Source_Ptr := Sloc (N);
242 Kind : constant Node_Kind := Nkind (Expression (N));
243 Target : constant Node_Id :=
244 Make_Attribute_Reference (Loc,
246 Attribute_Name => Name_Address);
248 Arg1 : constant Node_Id := Op1;
249 Arg2 : Node_Id := Op2;
251 Proc_Name : Entity_Id;
254 if Kind = N_Op_Not then
255 if Nkind (Op1) in N_Binary_Op then
257 -- Use negated version of the binary operators
259 if Nkind (Op1) = N_Op_And then
260 Proc_Name := RTE (RE_Vector_Nand);
262 elsif Nkind (Op1) = N_Op_Or then
263 Proc_Name := RTE (RE_Vector_Nor);
265 else pragma Assert (Nkind (Op1) = N_Op_Xor);
266 Proc_Name := RTE (RE_Vector_Xor);
270 Make_Procedure_Call_Statement (Loc,
271 Name => New_Occurrence_Of (Proc_Name, Loc),
273 Parameter_Associations => New_List (
275 Make_Attribute_Reference (Loc,
276 Prefix => Left_Opnd (Op1),
277 Attribute_Name => Name_Address),
279 Make_Attribute_Reference (Loc,
280 Prefix => Right_Opnd (Op1),
281 Attribute_Name => Name_Address),
283 Make_Attribute_Reference (Loc,
284 Prefix => Left_Opnd (Op1),
285 Attribute_Name => Name_Length)));
288 Proc_Name := RTE (RE_Vector_Not);
291 Make_Procedure_Call_Statement (Loc,
292 Name => New_Occurrence_Of (Proc_Name, Loc),
293 Parameter_Associations => New_List (
296 Make_Attribute_Reference (Loc,
298 Attribute_Name => Name_Address),
300 Make_Attribute_Reference (Loc,
302 Attribute_Name => Name_Length)));
306 -- We use the following equivalences:
308 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
309 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
310 -- (not X) xor (not Y) = X xor Y
311 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
313 if Nkind (Op1) = N_Op_Not then
314 if Kind = N_Op_And then
315 Proc_Name := RTE (RE_Vector_Nor);
317 elsif Kind = N_Op_Or then
318 Proc_Name := RTE (RE_Vector_Nand);
321 Proc_Name := RTE (RE_Vector_Xor);
325 if Kind = N_Op_And then
326 Proc_Name := RTE (RE_Vector_And);
328 elsif Kind = N_Op_Or then
329 Proc_Name := RTE (RE_Vector_Or);
331 elsif Nkind (Op2) = N_Op_Not then
332 Proc_Name := RTE (RE_Vector_Nxor);
333 Arg2 := Right_Opnd (Op2);
336 Proc_Name := RTE (RE_Vector_Xor);
341 Make_Procedure_Call_Statement (Loc,
342 Name => New_Occurrence_Of (Proc_Name, Loc),
343 Parameter_Associations => New_List (
345 Make_Attribute_Reference (Loc,
347 Attribute_Name => Name_Address),
348 Make_Attribute_Reference (Loc,
350 Attribute_Name => Name_Address),
351 Make_Attribute_Reference (Loc,
353 Attribute_Name => Name_Length)));
356 Rewrite (N, Call_Node);
360 when RE_Not_Available =>
362 end Build_Boolean_Array_Proc_Call;
364 --------------------------------
365 -- Displace_Allocator_Pointer --
366 --------------------------------
368 procedure Displace_Allocator_Pointer (N : Node_Id) is
369 Loc : constant Source_Ptr := Sloc (N);
370 Orig_Node : constant Node_Id := Original_Node (N);
376 -- Do nothing in case of VM targets: the virtual machine will handle
377 -- interfaces directly.
379 if VM_Target /= No_VM then
383 pragma Assert (Nkind (N) = N_Identifier
384 and then Nkind (Orig_Node) = N_Allocator);
386 PtrT := Etype (Orig_Node);
387 Dtyp := Designated_Type (PtrT);
388 Etyp := Etype (Expression (Orig_Node));
390 if Is_Class_Wide_Type (Dtyp)
391 and then Is_Interface (Dtyp)
393 -- If the type of the allocator expression is not an interface type
394 -- we can generate code to reference the record component containing
395 -- the pointer to the secondary dispatch table.
397 if not Is_Interface (Etyp) then
399 Saved_Typ : constant Entity_Id := Etype (Orig_Node);
402 -- 1) Get access to the allocated object
405 Make_Explicit_Dereference (Loc,
410 -- 2) Add the conversion to displace the pointer to reference
411 -- the secondary dispatch table.
413 Rewrite (N, Convert_To (Dtyp, Relocate_Node (N)));
414 Analyze_And_Resolve (N, Dtyp);
416 -- 3) The 'access to the secondary dispatch table will be used
417 -- as the value returned by the allocator.
420 Make_Attribute_Reference (Loc,
421 Prefix => Relocate_Node (N),
422 Attribute_Name => Name_Access));
423 Set_Etype (N, Saved_Typ);
427 -- If the type of the allocator expression is an interface type we
428 -- generate a run-time call to displace "this" to reference the
429 -- component containing the pointer to the secondary dispatch table
430 -- or else raise Constraint_Error if the actual object does not
431 -- implement the target interface. This case corresponds with the
432 -- following example:
434 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
436 -- return new Iface_2'Class'(Obj);
441 Unchecked_Convert_To (PtrT,
442 Make_Function_Call (Loc,
443 Name => New_Reference_To (RTE (RE_Displace), Loc),
444 Parameter_Associations => New_List (
445 Unchecked_Convert_To (RTE (RE_Address),
451 (Access_Disp_Table (Etype (Base_Type (Dtyp))))),
453 Analyze_And_Resolve (N, PtrT);
456 end Displace_Allocator_Pointer;
458 ---------------------------------
459 -- Expand_Allocator_Expression --
460 ---------------------------------
462 procedure Expand_Allocator_Expression (N : Node_Id) is
463 Loc : constant Source_Ptr := Sloc (N);
464 Exp : constant Node_Id := Expression (Expression (N));
465 PtrT : constant Entity_Id := Etype (N);
466 DesigT : constant Entity_Id := Designated_Type (PtrT);
468 procedure Apply_Accessibility_Check
470 Built_In_Place : Boolean := False);
471 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
472 -- type, generate an accessibility check to verify that the level of the
473 -- type of the created object is not deeper than the level of the access
474 -- type. If the type of the qualified expression is class- wide, then
475 -- always generate the check (except in the case where it is known to be
476 -- unnecessary, see comment below). Otherwise, only generate the check
477 -- if the level of the qualified expression type is statically deeper
478 -- than the access type.
480 -- Although the static accessibility will generally have been performed
481 -- as a legality check, it won't have been done in cases where the
482 -- allocator appears in generic body, so a run-time check is needed in
483 -- general. One special case is when the access type is declared in the
484 -- same scope as the class-wide allocator, in which case the check can
485 -- never fail, so it need not be generated.
487 -- As an open issue, there seem to be cases where the static level
488 -- associated with the class-wide object's underlying type is not
489 -- sufficient to perform the proper accessibility check, such as for
490 -- allocators in nested subprograms or accept statements initialized by
491 -- class-wide formals when the actual originates outside at a deeper
492 -- static level. The nested subprogram case might require passing
493 -- accessibility levels along with class-wide parameters, and the task
494 -- case seems to be an actual gap in the language rules that needs to
495 -- be fixed by the ARG. ???
497 -------------------------------
498 -- Apply_Accessibility_Check --
499 -------------------------------
501 procedure Apply_Accessibility_Check
503 Built_In_Place : Boolean := False)
508 -- Note: we skip the accessibility check for the VM case, since
509 -- there does not seem to be any practical way of implementing it.
511 if Ada_Version >= Ada_05
512 and then VM_Target = No_VM
513 and then Is_Class_Wide_Type (DesigT)
514 and then not Scope_Suppress (Accessibility_Check)
516 (Type_Access_Level (Etype (Exp)) > Type_Access_Level (PtrT)
518 (Is_Class_Wide_Type (Etype (Exp))
519 and then Scope (PtrT) /= Current_Scope))
521 -- If the allocator was built in place Ref is already a reference
522 -- to the access object initialized to the result of the allocator
523 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). Otherwise
524 -- it is the entity associated with the object containing the
525 -- address of the allocated object.
527 if Built_In_Place then
528 Ref_Node := New_Copy (Ref);
530 Ref_Node := New_Reference_To (Ref, Loc);
534 Make_Raise_Program_Error (Loc,
538 Build_Get_Access_Level (Loc,
539 Make_Attribute_Reference (Loc,
541 Attribute_Name => Name_Tag)),
543 Make_Integer_Literal (Loc,
544 Type_Access_Level (PtrT))),
545 Reason => PE_Accessibility_Check_Failed));
547 end Apply_Accessibility_Check;
551 Indic : constant Node_Id := Subtype_Mark (Expression (N));
552 T : constant Entity_Id := Entity (Indic);
557 TagT : Entity_Id := Empty;
558 -- Type used as source for tag assignment
560 TagR : Node_Id := Empty;
561 -- Target reference for tag assignment
563 Aggr_In_Place : constant Boolean := Is_Delayed_Aggregate (Exp);
565 Tag_Assign : Node_Id;
568 -- Start of processing for Expand_Allocator_Expression
571 if Is_Tagged_Type (T) or else Needs_Finalization (T) then
573 -- Ada 2005 (AI-318-02): If the initialization expression is a call
574 -- to a build-in-place function, then access to the allocated object
575 -- must be passed to the function. Currently we limit such functions
576 -- to those with constrained limited result subtypes, but eventually
577 -- we plan to expand the allowed forms of functions that are treated
578 -- as build-in-place.
580 if Ada_Version >= Ada_05
581 and then Is_Build_In_Place_Function_Call (Exp)
583 Make_Build_In_Place_Call_In_Allocator (N, Exp);
584 Apply_Accessibility_Check (N, Built_In_Place => True);
588 -- Actions inserted before:
589 -- Temp : constant ptr_T := new T'(Expression);
590 -- <no CW> Temp._tag := T'tag;
591 -- <CTRL> Adjust (Finalizable (Temp.all));
592 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
594 -- We analyze by hand the new internal allocator to avoid
595 -- any recursion and inappropriate call to Initialize
597 -- We don't want to remove side effects when the expression must be
598 -- built in place. In the case of a build-in-place function call,
599 -- that could lead to a duplication of the call, which was already
600 -- substituted for the allocator.
602 if not Aggr_In_Place then
603 Remove_Side_Effects (Exp);
607 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
609 -- For a class wide allocation generate the following code:
611 -- type Equiv_Record is record ... end record;
612 -- implicit subtype CW is <Class_Wide_Subytpe>;
613 -- temp : PtrT := new CW'(CW!(expr));
615 if Is_Class_Wide_Type (T) then
616 Expand_Subtype_From_Expr (Empty, T, Indic, Exp);
618 -- Ada 2005 (AI-251): If the expression is a class-wide interface
619 -- object we generate code to move up "this" to reference the
620 -- base of the object before allocating the new object.
622 -- Note that Exp'Address is recursively expanded into a call
623 -- to Base_Address (Exp.Tag)
625 if Is_Class_Wide_Type (Etype (Exp))
626 and then Is_Interface (Etype (Exp))
627 and then VM_Target = No_VM
631 Unchecked_Convert_To (Entity (Indic),
632 Make_Explicit_Dereference (Loc,
633 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
634 Make_Attribute_Reference (Loc,
636 Attribute_Name => Name_Address)))));
641 Unchecked_Convert_To (Entity (Indic), Exp));
644 Analyze_And_Resolve (Expression (N), Entity (Indic));
647 -- Keep separate the management of allocators returning interfaces
649 if not Is_Interface (Directly_Designated_Type (PtrT)) then
650 if Aggr_In_Place then
652 Make_Object_Declaration (Loc,
653 Defining_Identifier => Temp,
654 Object_Definition => New_Reference_To (PtrT, Loc),
657 New_Reference_To (Etype (Exp), Loc)));
659 Set_Comes_From_Source
660 (Expression (Tmp_Node), Comes_From_Source (N));
662 Set_No_Initialization (Expression (Tmp_Node));
663 Insert_Action (N, Tmp_Node);
665 if Needs_Finalization (T)
666 and then Ekind (PtrT) = E_Anonymous_Access_Type
668 -- Create local finalization list for access parameter
670 Flist := Get_Allocator_Final_List (N, Base_Type (T), PtrT);
673 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
675 Node := Relocate_Node (N);
678 Make_Object_Declaration (Loc,
679 Defining_Identifier => Temp,
680 Constant_Present => True,
681 Object_Definition => New_Reference_To (PtrT, Loc),
682 Expression => Node));
685 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
686 -- interface type. In this case we use the type of the qualified
687 -- expression to allocate the object.
691 Def_Id : constant Entity_Id :=
692 Make_Defining_Identifier (Loc,
693 New_Internal_Name ('T'));
698 Make_Full_Type_Declaration (Loc,
699 Defining_Identifier => Def_Id,
701 Make_Access_To_Object_Definition (Loc,
703 Null_Exclusion_Present => False,
704 Constant_Present => False,
705 Subtype_Indication =>
706 New_Reference_To (Etype (Exp), Loc)));
708 Insert_Action (N, New_Decl);
710 -- Inherit the final chain to ensure that the expansion of the
711 -- aggregate is correct in case of controlled types
713 if Needs_Finalization (Directly_Designated_Type (PtrT)) then
714 Set_Associated_Final_Chain (Def_Id,
715 Associated_Final_Chain (PtrT));
718 -- Declare the object using the previous type declaration
720 if Aggr_In_Place then
722 Make_Object_Declaration (Loc,
723 Defining_Identifier => Temp,
724 Object_Definition => New_Reference_To (Def_Id, Loc),
727 New_Reference_To (Etype (Exp), Loc)));
729 Set_Comes_From_Source
730 (Expression (Tmp_Node), Comes_From_Source (N));
732 Set_No_Initialization (Expression (Tmp_Node));
733 Insert_Action (N, Tmp_Node);
735 if Needs_Finalization (T)
736 and then Ekind (PtrT) = E_Anonymous_Access_Type
738 -- Create local finalization list for access parameter
741 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
744 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
746 Node := Relocate_Node (N);
749 Make_Object_Declaration (Loc,
750 Defining_Identifier => Temp,
751 Constant_Present => True,
752 Object_Definition => New_Reference_To (Def_Id, Loc),
753 Expression => Node));
756 -- Generate an additional object containing the address of the
757 -- returned object. The type of this second object declaration
758 -- is the correct type required for the common processing that
759 -- is still performed by this subprogram. The displacement of
760 -- this pointer to reference the component associated with the
761 -- interface type will be done at the end of common processing.
764 Make_Object_Declaration (Loc,
765 Defining_Identifier => Make_Defining_Identifier (Loc,
766 New_Internal_Name ('P')),
767 Object_Definition => New_Reference_To (PtrT, Loc),
768 Expression => Unchecked_Convert_To (PtrT,
769 New_Reference_To (Temp, Loc)));
771 Insert_Action (N, New_Decl);
773 Tmp_Node := New_Decl;
774 Temp := Defining_Identifier (New_Decl);
778 Apply_Accessibility_Check (Temp);
780 -- Generate the tag assignment
782 -- Suppress the tag assignment when VM_Target because VM tags are
783 -- represented implicitly in objects.
785 if VM_Target /= No_VM then
788 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
789 -- interface objects because in this case the tag does not change.
791 elsif Is_Interface (Directly_Designated_Type (Etype (N))) then
792 pragma Assert (Is_Class_Wide_Type
793 (Directly_Designated_Type (Etype (N))));
796 elsif Is_Tagged_Type (T) and then not Is_Class_Wide_Type (T) then
798 TagR := New_Reference_To (Temp, Loc);
800 elsif Is_Private_Type (T)
801 and then Is_Tagged_Type (Underlying_Type (T))
803 TagT := Underlying_Type (T);
805 Unchecked_Convert_To (Underlying_Type (T),
806 Make_Explicit_Dereference (Loc,
807 Prefix => New_Reference_To (Temp, Loc)));
810 if Present (TagT) then
812 Make_Assignment_Statement (Loc,
814 Make_Selected_Component (Loc,
817 New_Reference_To (First_Tag_Component (TagT), Loc)),
820 Unchecked_Convert_To (RTE (RE_Tag),
822 (Elists.Node (First_Elmt (Access_Disp_Table (TagT))),
825 -- The previous assignment has to be done in any case
827 Set_Assignment_OK (Name (Tag_Assign));
828 Insert_Action (N, Tag_Assign);
831 if Needs_Finalization (DesigT)
832 and then Needs_Finalization (T)
836 Apool : constant Entity_Id :=
837 Associated_Storage_Pool (PtrT);
840 -- If it is an allocation on the secondary stack (i.e. a value
841 -- returned from a function), the object is attached on the
842 -- caller side as soon as the call is completed (see
843 -- Expand_Ctrl_Function_Call)
845 if Is_RTE (Apool, RE_SS_Pool) then
847 F : constant Entity_Id :=
848 Make_Defining_Identifier (Loc,
849 New_Internal_Name ('F'));
852 Make_Object_Declaration (Loc,
853 Defining_Identifier => F,
854 Object_Definition => New_Reference_To (RTE
855 (RE_Finalizable_Ptr), Loc)));
857 Flist := New_Reference_To (F, Loc);
858 Attach := Make_Integer_Literal (Loc, 1);
861 -- Normal case, not a secondary stack allocation
864 if Needs_Finalization (T)
865 and then Ekind (PtrT) = E_Anonymous_Access_Type
867 -- Create local finalization list for access parameter
870 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
872 Flist := Find_Final_List (PtrT);
875 Attach := Make_Integer_Literal (Loc, 2);
878 -- Generate an Adjust call if the object will be moved. In Ada
879 -- 2005, the object may be inherently limited, in which case
880 -- there is no Adjust procedure, and the object is built in
881 -- place. In Ada 95, the object can be limited but not
882 -- inherently limited if this allocator came from a return
883 -- statement (we're allocating the result on the secondary
884 -- stack). In that case, the object will be moved, so we _do_
888 and then not Is_Inherently_Limited_Type (T)
894 -- An unchecked conversion is needed in the classwide
895 -- case because the designated type can be an ancestor of
896 -- the subtype mark of the allocator.
898 Unchecked_Convert_To (T,
899 Make_Explicit_Dereference (Loc,
900 Prefix => New_Reference_To (Temp, Loc))),
904 With_Attach => Attach,
910 Rewrite (N, New_Reference_To (Temp, Loc));
911 Analyze_And_Resolve (N, PtrT);
913 -- Ada 2005 (AI-251): Displace the pointer to reference the record
914 -- component containing the secondary dispatch table of the interface
917 if Is_Interface (Directly_Designated_Type (PtrT)) then
918 Displace_Allocator_Pointer (N);
921 elsif Aggr_In_Place then
923 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
925 Make_Object_Declaration (Loc,
926 Defining_Identifier => Temp,
927 Object_Definition => New_Reference_To (PtrT, Loc),
928 Expression => Make_Allocator (Loc,
929 New_Reference_To (Etype (Exp), Loc)));
931 Set_Comes_From_Source
932 (Expression (Tmp_Node), Comes_From_Source (N));
934 Set_No_Initialization (Expression (Tmp_Node));
935 Insert_Action (N, Tmp_Node);
936 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
937 Rewrite (N, New_Reference_To (Temp, Loc));
938 Analyze_And_Resolve (N, PtrT);
940 elsif Is_Access_Type (T)
941 and then Can_Never_Be_Null (T)
943 Install_Null_Excluding_Check (Exp);
945 elsif Is_Access_Type (DesigT)
946 and then Nkind (Exp) = N_Allocator
947 and then Nkind (Expression (Exp)) /= N_Qualified_Expression
949 -- Apply constraint to designated subtype indication
951 Apply_Constraint_Check (Expression (Exp),
952 Designated_Type (DesigT),
955 if Nkind (Expression (Exp)) = N_Raise_Constraint_Error then
957 -- Propagate constraint_error to enclosing allocator
959 Rewrite (Exp, New_Copy (Expression (Exp)));
962 -- First check against the type of the qualified expression
964 -- NOTE: The commented call should be correct, but for some reason
965 -- causes the compiler to bomb (sigsegv) on ACVC test c34007g, so for
966 -- now we just perform the old (incorrect) test against the
967 -- designated subtype with no sliding in the else part of the if
968 -- statement below. ???
970 -- Apply_Constraint_Check (Exp, T, No_Sliding => True);
972 -- A check is also needed in cases where the designated subtype is
973 -- constrained and differs from the subtype given in the qualified
974 -- expression. Note that the check on the qualified expression does
975 -- not allow sliding, but this check does (a relaxation from Ada 83).
977 if Is_Constrained (DesigT)
978 and then not Subtypes_Statically_Match (T, DesigT)
980 Apply_Constraint_Check
981 (Exp, DesigT, No_Sliding => False);
983 -- The nonsliding check should really be performed (unconditionally)
984 -- against the subtype of the qualified expression, but that causes a
985 -- problem with c34007g (see above), so for now we retain this.
988 Apply_Constraint_Check
989 (Exp, DesigT, No_Sliding => True);
992 -- For an access to unconstrained packed array, GIGI needs to see an
993 -- expression with a constrained subtype in order to compute the
994 -- proper size for the allocator.
997 and then not Is_Constrained (T)
998 and then Is_Packed (T)
1001 ConstrT : constant Entity_Id :=
1002 Make_Defining_Identifier (Loc,
1003 Chars => New_Internal_Name ('A'));
1004 Internal_Exp : constant Node_Id := Relocate_Node (Exp);
1007 Make_Subtype_Declaration (Loc,
1008 Defining_Identifier => ConstrT,
1009 Subtype_Indication =>
1010 Make_Subtype_From_Expr (Exp, T)));
1011 Freeze_Itype (ConstrT, Exp);
1012 Rewrite (Exp, OK_Convert_To (ConstrT, Internal_Exp));
1016 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1017 -- to a build-in-place function, then access to the allocated object
1018 -- must be passed to the function. Currently we limit such functions
1019 -- to those with constrained limited result subtypes, but eventually
1020 -- we plan to expand the allowed forms of functions that are treated
1021 -- as build-in-place.
1023 if Ada_Version >= Ada_05
1024 and then Is_Build_In_Place_Function_Call (Exp)
1026 Make_Build_In_Place_Call_In_Allocator (N, Exp);
1031 when RE_Not_Available =>
1033 end Expand_Allocator_Expression;
1035 -----------------------------
1036 -- Expand_Array_Comparison --
1037 -----------------------------
1039 -- Expansion is only required in the case of array types. For the unpacked
1040 -- case, an appropriate runtime routine is called. For packed cases, and
1041 -- also in some other cases where a runtime routine cannot be called, the
1042 -- form of the expansion is:
1044 -- [body for greater_nn; boolean_expression]
1046 -- The body is built by Make_Array_Comparison_Op, and the form of the
1047 -- Boolean expression depends on the operator involved.
1049 procedure Expand_Array_Comparison (N : Node_Id) is
1050 Loc : constant Source_Ptr := Sloc (N);
1051 Op1 : Node_Id := Left_Opnd (N);
1052 Op2 : Node_Id := Right_Opnd (N);
1053 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
1054 Ctyp : constant Entity_Id := Component_Type (Typ1);
1057 Func_Body : Node_Id;
1058 Func_Name : Entity_Id;
1062 Byte_Addressable : constant Boolean := System_Storage_Unit = Byte'Size;
1063 -- True for byte addressable target
1065 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean;
1066 -- Returns True if the length of the given operand is known to be less
1067 -- than 4. Returns False if this length is known to be four or greater
1068 -- or is not known at compile time.
1070 ------------------------
1071 -- Length_Less_Than_4 --
1072 ------------------------
1074 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean is
1075 Otyp : constant Entity_Id := Etype (Opnd);
1078 if Ekind (Otyp) = E_String_Literal_Subtype then
1079 return String_Literal_Length (Otyp) < 4;
1083 Ityp : constant Entity_Id := Etype (First_Index (Otyp));
1084 Lo : constant Node_Id := Type_Low_Bound (Ityp);
1085 Hi : constant Node_Id := Type_High_Bound (Ityp);
1090 if Compile_Time_Known_Value (Lo) then
1091 Lov := Expr_Value (Lo);
1096 if Compile_Time_Known_Value (Hi) then
1097 Hiv := Expr_Value (Hi);
1102 return Hiv < Lov + 3;
1105 end Length_Less_Than_4;
1107 -- Start of processing for Expand_Array_Comparison
1110 -- Deal first with unpacked case, where we can call a runtime routine
1111 -- except that we avoid this for targets for which are not addressable
1112 -- by bytes, and for the JVM/CIL, since they do not support direct
1113 -- addressing of array components.
1115 if not Is_Bit_Packed_Array (Typ1)
1116 and then Byte_Addressable
1117 and then VM_Target = No_VM
1119 -- The call we generate is:
1121 -- Compare_Array_xn[_Unaligned]
1122 -- (left'address, right'address, left'length, right'length) <op> 0
1124 -- x = U for unsigned, S for signed
1125 -- n = 8,16,32,64 for component size
1126 -- Add _Unaligned if length < 4 and component size is 8.
1127 -- <op> is the standard comparison operator
1129 if Component_Size (Typ1) = 8 then
1130 if Length_Less_Than_4 (Op1)
1132 Length_Less_Than_4 (Op2)
1134 if Is_Unsigned_Type (Ctyp) then
1135 Comp := RE_Compare_Array_U8_Unaligned;
1137 Comp := RE_Compare_Array_S8_Unaligned;
1141 if Is_Unsigned_Type (Ctyp) then
1142 Comp := RE_Compare_Array_U8;
1144 Comp := RE_Compare_Array_S8;
1148 elsif Component_Size (Typ1) = 16 then
1149 if Is_Unsigned_Type (Ctyp) then
1150 Comp := RE_Compare_Array_U16;
1152 Comp := RE_Compare_Array_S16;
1155 elsif Component_Size (Typ1) = 32 then
1156 if Is_Unsigned_Type (Ctyp) then
1157 Comp := RE_Compare_Array_U32;
1159 Comp := RE_Compare_Array_S32;
1162 else pragma Assert (Component_Size (Typ1) = 64);
1163 if Is_Unsigned_Type (Ctyp) then
1164 Comp := RE_Compare_Array_U64;
1166 Comp := RE_Compare_Array_S64;
1170 Remove_Side_Effects (Op1, Name_Req => True);
1171 Remove_Side_Effects (Op2, Name_Req => True);
1174 Make_Function_Call (Sloc (Op1),
1175 Name => New_Occurrence_Of (RTE (Comp), Loc),
1177 Parameter_Associations => New_List (
1178 Make_Attribute_Reference (Loc,
1179 Prefix => Relocate_Node (Op1),
1180 Attribute_Name => Name_Address),
1182 Make_Attribute_Reference (Loc,
1183 Prefix => Relocate_Node (Op2),
1184 Attribute_Name => Name_Address),
1186 Make_Attribute_Reference (Loc,
1187 Prefix => Relocate_Node (Op1),
1188 Attribute_Name => Name_Length),
1190 Make_Attribute_Reference (Loc,
1191 Prefix => Relocate_Node (Op2),
1192 Attribute_Name => Name_Length))));
1195 Make_Integer_Literal (Sloc (Op2),
1198 Analyze_And_Resolve (Op1, Standard_Integer);
1199 Analyze_And_Resolve (Op2, Standard_Integer);
1203 -- Cases where we cannot make runtime call
1205 -- For (a <= b) we convert to not (a > b)
1207 if Chars (N) = Name_Op_Le then
1213 Right_Opnd => Op2)));
1214 Analyze_And_Resolve (N, Standard_Boolean);
1217 -- For < the Boolean expression is
1218 -- greater__nn (op2, op1)
1220 elsif Chars (N) = Name_Op_Lt then
1221 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1225 Op1 := Right_Opnd (N);
1226 Op2 := Left_Opnd (N);
1228 -- For (a >= b) we convert to not (a < b)
1230 elsif Chars (N) = Name_Op_Ge then
1236 Right_Opnd => Op2)));
1237 Analyze_And_Resolve (N, Standard_Boolean);
1240 -- For > the Boolean expression is
1241 -- greater__nn (op1, op2)
1244 pragma Assert (Chars (N) = Name_Op_Gt);
1245 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1248 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1250 Make_Function_Call (Loc,
1251 Name => New_Reference_To (Func_Name, Loc),
1252 Parameter_Associations => New_List (Op1, Op2));
1254 Insert_Action (N, Func_Body);
1256 Analyze_And_Resolve (N, Standard_Boolean);
1259 when RE_Not_Available =>
1261 end Expand_Array_Comparison;
1263 ---------------------------
1264 -- Expand_Array_Equality --
1265 ---------------------------
1267 -- Expand an equality function for multi-dimensional arrays. Here is an
1268 -- example of such a function for Nb_Dimension = 2
1270 -- function Enn (A : atyp; B : btyp) return boolean is
1272 -- if (A'length (1) = 0 or else A'length (2) = 0)
1274 -- (B'length (1) = 0 or else B'length (2) = 0)
1276 -- return True; -- RM 4.5.2(22)
1279 -- if A'length (1) /= B'length (1)
1281 -- A'length (2) /= B'length (2)
1283 -- return False; -- RM 4.5.2(23)
1287 -- A1 : Index_T1 := A'first (1);
1288 -- B1 : Index_T1 := B'first (1);
1292 -- A2 : Index_T2 := A'first (2);
1293 -- B2 : Index_T2 := B'first (2);
1296 -- if A (A1, A2) /= B (B1, B2) then
1300 -- exit when A2 = A'last (2);
1301 -- A2 := Index_T2'succ (A2);
1302 -- B2 := Index_T2'succ (B2);
1306 -- exit when A1 = A'last (1);
1307 -- A1 := Index_T1'succ (A1);
1308 -- B1 := Index_T1'succ (B1);
1315 -- Note on the formal types used (atyp and btyp). If either of the arrays
1316 -- is of a private type, we use the underlying type, and do an unchecked
1317 -- conversion of the actual. If either of the arrays has a bound depending
1318 -- on a discriminant, then we use the base type since otherwise we have an
1319 -- escaped discriminant in the function.
1321 -- If both arrays are constrained and have the same bounds, we can generate
1322 -- a loop with an explicit iteration scheme using a 'Range attribute over
1325 function Expand_Array_Equality
1330 Typ : Entity_Id) return Node_Id
1332 Loc : constant Source_Ptr := Sloc (Nod);
1333 Decls : constant List_Id := New_List;
1334 Index_List1 : constant List_Id := New_List;
1335 Index_List2 : constant List_Id := New_List;
1339 Func_Name : Entity_Id;
1340 Func_Body : Node_Id;
1342 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
1343 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
1347 -- The parameter types to be used for the formals
1352 Num : Int) return Node_Id;
1353 -- This builds the attribute reference Arr'Nam (Expr)
1355 function Component_Equality (Typ : Entity_Id) return Node_Id;
1356 -- Create one statement to compare corresponding components, designated
1357 -- by a full set of indices.
1359 function Get_Arg_Type (N : Node_Id) return Entity_Id;
1360 -- Given one of the arguments, computes the appropriate type to be used
1361 -- for that argument in the corresponding function formal
1363 function Handle_One_Dimension
1365 Index : Node_Id) return Node_Id;
1366 -- This procedure returns the following code
1369 -- Bn : Index_T := B'First (N);
1373 -- exit when An = A'Last (N);
1374 -- An := Index_T'Succ (An)
1375 -- Bn := Index_T'Succ (Bn)
1379 -- If both indices are constrained and identical, the procedure
1380 -- returns a simpler loop:
1382 -- for An in A'Range (N) loop
1386 -- N is the dimension for which we are generating a loop. Index is the
1387 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1388 -- xxx statement is either the loop or declare for the next dimension
1389 -- or if this is the last dimension the comparison of corresponding
1390 -- components of the arrays.
1392 -- The actual way the code works is to return the comparison of
1393 -- corresponding components for the N+1 call. That's neater!
1395 function Test_Empty_Arrays return Node_Id;
1396 -- This function constructs the test for both arrays being empty
1397 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1399 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1401 function Test_Lengths_Correspond return Node_Id;
1402 -- This function constructs the test for arrays having different lengths
1403 -- in at least one index position, in which case the resulting code is:
1405 -- A'length (1) /= B'length (1)
1407 -- A'length (2) /= B'length (2)
1418 Num : Int) return Node_Id
1422 Make_Attribute_Reference (Loc,
1423 Attribute_Name => Nam,
1424 Prefix => New_Reference_To (Arr, Loc),
1425 Expressions => New_List (Make_Integer_Literal (Loc, Num)));
1428 ------------------------
1429 -- Component_Equality --
1430 ------------------------
1432 function Component_Equality (Typ : Entity_Id) return Node_Id is
1437 -- if a(i1...) /= b(j1...) then return false; end if;
1440 Make_Indexed_Component (Loc,
1441 Prefix => Make_Identifier (Loc, Chars (A)),
1442 Expressions => Index_List1);
1445 Make_Indexed_Component (Loc,
1446 Prefix => Make_Identifier (Loc, Chars (B)),
1447 Expressions => Index_List2);
1449 Test := Expand_Composite_Equality
1450 (Nod, Component_Type (Typ), L, R, Decls);
1452 -- If some (sub)component is an unchecked_union, the whole operation
1453 -- will raise program error.
1455 if Nkind (Test) = N_Raise_Program_Error then
1457 -- This node is going to be inserted at a location where a
1458 -- statement is expected: clear its Etype so analysis will set
1459 -- it to the expected Standard_Void_Type.
1461 Set_Etype (Test, Empty);
1466 Make_Implicit_If_Statement (Nod,
1467 Condition => Make_Op_Not (Loc, Right_Opnd => Test),
1468 Then_Statements => New_List (
1469 Make_Simple_Return_Statement (Loc,
1470 Expression => New_Occurrence_Of (Standard_False, Loc))));
1472 end Component_Equality;
1478 function Get_Arg_Type (N : Node_Id) return Entity_Id is
1489 T := Underlying_Type (T);
1491 X := First_Index (T);
1492 while Present (X) loop
1493 if Denotes_Discriminant (Type_Low_Bound (Etype (X)))
1495 Denotes_Discriminant (Type_High_Bound (Etype (X)))
1508 --------------------------
1509 -- Handle_One_Dimension --
1510 ---------------------------
1512 function Handle_One_Dimension
1514 Index : Node_Id) return Node_Id
1516 Need_Separate_Indexes : constant Boolean :=
1518 or else not Is_Constrained (Ltyp);
1519 -- If the index types are identical, and we are working with
1520 -- constrained types, then we can use the same index for both
1523 An : constant Entity_Id := Make_Defining_Identifier (Loc,
1524 Chars => New_Internal_Name ('A'));
1527 Index_T : Entity_Id;
1532 if N > Number_Dimensions (Ltyp) then
1533 return Component_Equality (Ltyp);
1536 -- Case where we generate a loop
1538 Index_T := Base_Type (Etype (Index));
1540 if Need_Separate_Indexes then
1542 Make_Defining_Identifier (Loc,
1543 Chars => New_Internal_Name ('B'));
1548 Append (New_Reference_To (An, Loc), Index_List1);
1549 Append (New_Reference_To (Bn, Loc), Index_List2);
1551 Stm_List := New_List (
1552 Handle_One_Dimension (N + 1, Next_Index (Index)));
1554 if Need_Separate_Indexes then
1556 -- Generate guard for loop, followed by increments of indices
1558 Append_To (Stm_List,
1559 Make_Exit_Statement (Loc,
1562 Left_Opnd => New_Reference_To (An, Loc),
1563 Right_Opnd => Arr_Attr (A, Name_Last, N))));
1565 Append_To (Stm_List,
1566 Make_Assignment_Statement (Loc,
1567 Name => New_Reference_To (An, Loc),
1569 Make_Attribute_Reference (Loc,
1570 Prefix => New_Reference_To (Index_T, Loc),
1571 Attribute_Name => Name_Succ,
1572 Expressions => New_List (New_Reference_To (An, Loc)))));
1574 Append_To (Stm_List,
1575 Make_Assignment_Statement (Loc,
1576 Name => New_Reference_To (Bn, Loc),
1578 Make_Attribute_Reference (Loc,
1579 Prefix => New_Reference_To (Index_T, Loc),
1580 Attribute_Name => Name_Succ,
1581 Expressions => New_List (New_Reference_To (Bn, Loc)))));
1584 -- If separate indexes, we need a declare block for An and Bn, and a
1585 -- loop without an iteration scheme.
1587 if Need_Separate_Indexes then
1589 Make_Implicit_Loop_Statement (Nod, Statements => Stm_List);
1592 Make_Block_Statement (Loc,
1593 Declarations => New_List (
1594 Make_Object_Declaration (Loc,
1595 Defining_Identifier => An,
1596 Object_Definition => New_Reference_To (Index_T, Loc),
1597 Expression => Arr_Attr (A, Name_First, N)),
1599 Make_Object_Declaration (Loc,
1600 Defining_Identifier => Bn,
1601 Object_Definition => New_Reference_To (Index_T, Loc),
1602 Expression => Arr_Attr (B, Name_First, N))),
1604 Handled_Statement_Sequence =>
1605 Make_Handled_Sequence_Of_Statements (Loc,
1606 Statements => New_List (Loop_Stm)));
1608 -- If no separate indexes, return loop statement with explicit
1609 -- iteration scheme on its own
1613 Make_Implicit_Loop_Statement (Nod,
1614 Statements => Stm_List,
1616 Make_Iteration_Scheme (Loc,
1617 Loop_Parameter_Specification =>
1618 Make_Loop_Parameter_Specification (Loc,
1619 Defining_Identifier => An,
1620 Discrete_Subtype_Definition =>
1621 Arr_Attr (A, Name_Range, N))));
1624 end Handle_One_Dimension;
1626 -----------------------
1627 -- Test_Empty_Arrays --
1628 -----------------------
1630 function Test_Empty_Arrays return Node_Id is
1640 for J in 1 .. Number_Dimensions (Ltyp) loop
1643 Left_Opnd => Arr_Attr (A, Name_Length, J),
1644 Right_Opnd => Make_Integer_Literal (Loc, 0));
1648 Left_Opnd => Arr_Attr (B, Name_Length, J),
1649 Right_Opnd => Make_Integer_Literal (Loc, 0));
1658 Left_Opnd => Relocate_Node (Alist),
1659 Right_Opnd => Atest);
1663 Left_Opnd => Relocate_Node (Blist),
1664 Right_Opnd => Btest);
1671 Right_Opnd => Blist);
1672 end Test_Empty_Arrays;
1674 -----------------------------
1675 -- Test_Lengths_Correspond --
1676 -----------------------------
1678 function Test_Lengths_Correspond return Node_Id is
1684 for J in 1 .. Number_Dimensions (Ltyp) loop
1687 Left_Opnd => Arr_Attr (A, Name_Length, J),
1688 Right_Opnd => Arr_Attr (B, Name_Length, J));
1695 Left_Opnd => Relocate_Node (Result),
1696 Right_Opnd => Rtest);
1701 end Test_Lengths_Correspond;
1703 -- Start of processing for Expand_Array_Equality
1706 Ltyp := Get_Arg_Type (Lhs);
1707 Rtyp := Get_Arg_Type (Rhs);
1709 -- For now, if the argument types are not the same, go to the base type,
1710 -- since the code assumes that the formals have the same type. This is
1711 -- fixable in future ???
1713 if Ltyp /= Rtyp then
1714 Ltyp := Base_Type (Ltyp);
1715 Rtyp := Base_Type (Rtyp);
1716 pragma Assert (Ltyp = Rtyp);
1719 -- Build list of formals for function
1721 Formals := New_List (
1722 Make_Parameter_Specification (Loc,
1723 Defining_Identifier => A,
1724 Parameter_Type => New_Reference_To (Ltyp, Loc)),
1726 Make_Parameter_Specification (Loc,
1727 Defining_Identifier => B,
1728 Parameter_Type => New_Reference_To (Rtyp, Loc)));
1730 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('E'));
1732 -- Build statement sequence for function
1735 Make_Subprogram_Body (Loc,
1737 Make_Function_Specification (Loc,
1738 Defining_Unit_Name => Func_Name,
1739 Parameter_Specifications => Formals,
1740 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
1742 Declarations => Decls,
1744 Handled_Statement_Sequence =>
1745 Make_Handled_Sequence_Of_Statements (Loc,
1746 Statements => New_List (
1748 Make_Implicit_If_Statement (Nod,
1749 Condition => Test_Empty_Arrays,
1750 Then_Statements => New_List (
1751 Make_Simple_Return_Statement (Loc,
1753 New_Occurrence_Of (Standard_True, Loc)))),
1755 Make_Implicit_If_Statement (Nod,
1756 Condition => Test_Lengths_Correspond,
1757 Then_Statements => New_List (
1758 Make_Simple_Return_Statement (Loc,
1760 New_Occurrence_Of (Standard_False, Loc)))),
1762 Handle_One_Dimension (1, First_Index (Ltyp)),
1764 Make_Simple_Return_Statement (Loc,
1765 Expression => New_Occurrence_Of (Standard_True, Loc)))));
1767 Set_Has_Completion (Func_Name, True);
1768 Set_Is_Inlined (Func_Name);
1770 -- If the array type is distinct from the type of the arguments, it
1771 -- is the full view of a private type. Apply an unchecked conversion
1772 -- to insure that analysis of the call succeeds.
1782 or else Base_Type (Etype (Lhs)) /= Base_Type (Ltyp)
1784 L := OK_Convert_To (Ltyp, Lhs);
1788 or else Base_Type (Etype (Rhs)) /= Base_Type (Rtyp)
1790 R := OK_Convert_To (Rtyp, Rhs);
1793 Actuals := New_List (L, R);
1796 Append_To (Bodies, Func_Body);
1799 Make_Function_Call (Loc,
1800 Name => New_Reference_To (Func_Name, Loc),
1801 Parameter_Associations => Actuals);
1802 end Expand_Array_Equality;
1804 -----------------------------
1805 -- Expand_Boolean_Operator --
1806 -----------------------------
1808 -- Note that we first get the actual subtypes of the operands, since we
1809 -- always want to deal with types that have bounds.
1811 procedure Expand_Boolean_Operator (N : Node_Id) is
1812 Typ : constant Entity_Id := Etype (N);
1815 -- Special case of bit packed array where both operands are known to be
1816 -- properly aligned. In this case we use an efficient run time routine
1817 -- to carry out the operation (see System.Bit_Ops).
1819 if Is_Bit_Packed_Array (Typ)
1820 and then not Is_Possibly_Unaligned_Object (Left_Opnd (N))
1821 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
1823 Expand_Packed_Boolean_Operator (N);
1827 -- For the normal non-packed case, the general expansion is to build
1828 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
1829 -- and then inserting it into the tree. The original operator node is
1830 -- then rewritten as a call to this function. We also use this in the
1831 -- packed case if either operand is a possibly unaligned object.
1834 Loc : constant Source_Ptr := Sloc (N);
1835 L : constant Node_Id := Relocate_Node (Left_Opnd (N));
1836 R : constant Node_Id := Relocate_Node (Right_Opnd (N));
1837 Func_Body : Node_Id;
1838 Func_Name : Entity_Id;
1841 Convert_To_Actual_Subtype (L);
1842 Convert_To_Actual_Subtype (R);
1843 Ensure_Defined (Etype (L), N);
1844 Ensure_Defined (Etype (R), N);
1845 Apply_Length_Check (R, Etype (L));
1847 if Nkind (N) = N_Op_Xor then
1848 Silly_Boolean_Array_Xor_Test (N, Etype (L));
1851 if Nkind (Parent (N)) = N_Assignment_Statement
1852 and then Safe_In_Place_Array_Op (Name (Parent (N)), L, R)
1854 Build_Boolean_Array_Proc_Call (Parent (N), L, R);
1856 elsif Nkind (Parent (N)) = N_Op_Not
1857 and then Nkind (N) = N_Op_And
1859 Safe_In_Place_Array_Op (Name (Parent (Parent (N))), L, R)
1864 Func_Body := Make_Boolean_Array_Op (Etype (L), N);
1865 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1866 Insert_Action (N, Func_Body);
1868 -- Now rewrite the expression with a call
1871 Make_Function_Call (Loc,
1872 Name => New_Reference_To (Func_Name, Loc),
1873 Parameter_Associations =>
1876 Make_Type_Conversion
1877 (Loc, New_Reference_To (Etype (L), Loc), R))));
1879 Analyze_And_Resolve (N, Typ);
1882 end Expand_Boolean_Operator;
1884 -------------------------------
1885 -- Expand_Composite_Equality --
1886 -------------------------------
1888 -- This function is only called for comparing internal fields of composite
1889 -- types when these fields are themselves composites. This is a special
1890 -- case because it is not possible to respect normal Ada visibility rules.
1892 function Expand_Composite_Equality
1897 Bodies : List_Id) return Node_Id
1899 Loc : constant Source_Ptr := Sloc (Nod);
1900 Full_Type : Entity_Id;
1905 if Is_Private_Type (Typ) then
1906 Full_Type := Underlying_Type (Typ);
1911 -- Defense against malformed private types with no completion the error
1912 -- will be diagnosed later by check_completion
1914 if No (Full_Type) then
1915 return New_Reference_To (Standard_False, Loc);
1918 Full_Type := Base_Type (Full_Type);
1920 if Is_Array_Type (Full_Type) then
1922 -- If the operand is an elementary type other than a floating-point
1923 -- type, then we can simply use the built-in block bitwise equality,
1924 -- since the predefined equality operators always apply and bitwise
1925 -- equality is fine for all these cases.
1927 if Is_Elementary_Type (Component_Type (Full_Type))
1928 and then not Is_Floating_Point_Type (Component_Type (Full_Type))
1930 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
1932 -- For composite component types, and floating-point types, use the
1933 -- expansion. This deals with tagged component types (where we use
1934 -- the applicable equality routine) and floating-point, (where we
1935 -- need to worry about negative zeroes), and also the case of any
1936 -- composite type recursively containing such fields.
1939 return Expand_Array_Equality (Nod, Lhs, Rhs, Bodies, Full_Type);
1942 elsif Is_Tagged_Type (Full_Type) then
1944 -- Call the primitive operation "=" of this type
1946 if Is_Class_Wide_Type (Full_Type) then
1947 Full_Type := Root_Type (Full_Type);
1950 -- If this is derived from an untagged private type completed with a
1951 -- tagged type, it does not have a full view, so we use the primitive
1952 -- operations of the private type. This check should no longer be
1953 -- necessary when these types receive their full views ???
1955 if Is_Private_Type (Typ)
1956 and then not Is_Tagged_Type (Typ)
1957 and then not Is_Controlled (Typ)
1958 and then Is_Derived_Type (Typ)
1959 and then No (Full_View (Typ))
1961 Prim := First_Elmt (Collect_Primitive_Operations (Typ));
1963 Prim := First_Elmt (Primitive_Operations (Full_Type));
1967 Eq_Op := Node (Prim);
1968 exit when Chars (Eq_Op) = Name_Op_Eq
1969 and then Etype (First_Formal (Eq_Op)) =
1970 Etype (Next_Formal (First_Formal (Eq_Op)))
1971 and then Base_Type (Etype (Eq_Op)) = Standard_Boolean;
1973 pragma Assert (Present (Prim));
1976 Eq_Op := Node (Prim);
1979 Make_Function_Call (Loc,
1980 Name => New_Reference_To (Eq_Op, Loc),
1981 Parameter_Associations =>
1983 (Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Lhs),
1984 Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Rhs)));
1986 elsif Is_Record_Type (Full_Type) then
1987 Eq_Op := TSS (Full_Type, TSS_Composite_Equality);
1989 if Present (Eq_Op) then
1990 if Etype (First_Formal (Eq_Op)) /= Full_Type then
1992 -- Inherited equality from parent type. Convert the actuals to
1993 -- match signature of operation.
1996 T : constant Entity_Id := Etype (First_Formal (Eq_Op));
2000 Make_Function_Call (Loc,
2001 Name => New_Reference_To (Eq_Op, Loc),
2002 Parameter_Associations =>
2003 New_List (OK_Convert_To (T, Lhs),
2004 OK_Convert_To (T, Rhs)));
2008 -- Comparison between Unchecked_Union components
2010 if Is_Unchecked_Union (Full_Type) then
2012 Lhs_Type : Node_Id := Full_Type;
2013 Rhs_Type : Node_Id := Full_Type;
2014 Lhs_Discr_Val : Node_Id;
2015 Rhs_Discr_Val : Node_Id;
2020 if Nkind (Lhs) = N_Selected_Component then
2021 Lhs_Type := Etype (Entity (Selector_Name (Lhs)));
2026 if Nkind (Rhs) = N_Selected_Component then
2027 Rhs_Type := Etype (Entity (Selector_Name (Rhs)));
2030 -- Lhs of the composite equality
2032 if Is_Constrained (Lhs_Type) then
2034 -- Since the enclosing record type can never be an
2035 -- Unchecked_Union (this code is executed for records
2036 -- that do not have variants), we may reference its
2039 if Nkind (Lhs) = N_Selected_Component
2040 and then Has_Per_Object_Constraint (
2041 Entity (Selector_Name (Lhs)))
2044 Make_Selected_Component (Loc,
2045 Prefix => Prefix (Lhs),
2048 Get_Discriminant_Value (
2049 First_Discriminant (Lhs_Type),
2051 Stored_Constraint (Lhs_Type))));
2054 Lhs_Discr_Val := New_Copy (
2055 Get_Discriminant_Value (
2056 First_Discriminant (Lhs_Type),
2058 Stored_Constraint (Lhs_Type)));
2062 -- It is not possible to infer the discriminant since
2063 -- the subtype is not constrained.
2066 Make_Raise_Program_Error (Loc,
2067 Reason => PE_Unchecked_Union_Restriction);
2070 -- Rhs of the composite equality
2072 if Is_Constrained (Rhs_Type) then
2073 if Nkind (Rhs) = N_Selected_Component
2074 and then Has_Per_Object_Constraint (
2075 Entity (Selector_Name (Rhs)))
2078 Make_Selected_Component (Loc,
2079 Prefix => Prefix (Rhs),
2082 Get_Discriminant_Value (
2083 First_Discriminant (Rhs_Type),
2085 Stored_Constraint (Rhs_Type))));
2088 Rhs_Discr_Val := New_Copy (
2089 Get_Discriminant_Value (
2090 First_Discriminant (Rhs_Type),
2092 Stored_Constraint (Rhs_Type)));
2097 Make_Raise_Program_Error (Loc,
2098 Reason => PE_Unchecked_Union_Restriction);
2101 -- Call the TSS equality function with the inferred
2102 -- discriminant values.
2105 Make_Function_Call (Loc,
2106 Name => New_Reference_To (Eq_Op, Loc),
2107 Parameter_Associations => New_List (
2115 -- Shouldn't this be an else, we can't fall through the above
2119 Make_Function_Call (Loc,
2120 Name => New_Reference_To (Eq_Op, Loc),
2121 Parameter_Associations => New_List (Lhs, Rhs));
2125 return Expand_Record_Equality (Nod, Full_Type, Lhs, Rhs, Bodies);
2129 -- It can be a simple record or the full view of a scalar private
2131 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2133 end Expand_Composite_Equality;
2135 ------------------------
2136 -- Expand_Concatenate --
2137 ------------------------
2139 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id) is
2140 Loc : constant Source_Ptr := Sloc (Cnode);
2142 Atyp : constant Entity_Id := Base_Type (Etype (Cnode));
2143 -- Result type of concatenation
2145 Ctyp : constant Entity_Id := Base_Type (Component_Type (Etype (Cnode)));
2146 -- Component type. Elements of this component type can appear as one
2147 -- of the operands of concatenation as well as arrays.
2149 Istyp : constant Entity_Id := Etype (First_Index (Atyp));
2152 Ityp : constant Entity_Id := Base_Type (Istyp);
2153 -- Index type. This is the base type of the index subtype, and is used
2154 -- for all computed bounds (which may be out of range of Istyp in the
2155 -- case of null ranges).
2158 -- This is the type we use to do arithmetic to compute the bounds and
2159 -- lengths of operands. The choice of this type is a little subtle and
2160 -- is discussed in a separate section at the start of the body code.
2162 Concatenation_Error : exception;
2163 -- Raised if concatenation is sure to raise a CE
2165 Result_May_Be_Null : Boolean := True;
2166 -- Reset to False if at least one operand is encountered which is known
2167 -- at compile time to be non-null. Used for handling the special case
2168 -- of setting the high bound to the last operand high bound for a null
2169 -- result, thus ensuring a proper high bound in the super-flat case.
2171 N : constant Nat := List_Length (Opnds);
2172 -- Number of concatenation operands including possibly null operands
2175 -- Number of operands excluding any known to be null, except that the
2176 -- last operand is always retained, in case it provides the bounds for
2180 -- Current operand being processed in the loop through operands. After
2181 -- this loop is complete, always contains the last operand (which is not
2182 -- the same as Operands (NN), since null operands are skipped).
2184 -- Arrays describing the operands, only the first NN entries of each
2185 -- array are set (NN < N when we exclude known null operands).
2187 Is_Fixed_Length : array (1 .. N) of Boolean;
2188 -- True if length of corresponding operand known at compile time
2190 Operands : array (1 .. N) of Node_Id;
2191 -- Set to the corresponding entry in the Opnds list (but note that null
2192 -- operands are excluded, so not all entries in the list are stored).
2194 Fixed_Length : array (1 .. N) of Uint;
2195 -- Set to length of operand. Entries in this array are set only if the
2196 -- corresponding entry in Is_Fixed_Length is True.
2198 Opnd_Low_Bound : array (1 .. N) of Node_Id;
2199 -- Set to lower bound of operand. Either an integer literal in the case
2200 -- where the bound is known at compile time, else actual lower bound.
2201 -- The operand low bound is of type Ityp.
2203 Var_Length : array (1 .. N) of Entity_Id;
2204 -- Set to an entity of type Natural that contains the length of an
2205 -- operand whose length is not known at compile time. Entries in this
2206 -- array are set only if the corresponding entry in Is_Fixed_Length
2207 -- is False. The entity is of type Artyp.
2209 Aggr_Length : array (0 .. N) of Node_Id;
2210 -- The J'th entry in an expression node that represents the total length
2211 -- of operands 1 through J. It is either an integer literal node, or a
2212 -- reference to a constant entity with the right value, so it is fine
2213 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2214 -- entry always is set to zero. The length is of type Artyp.
2216 Low_Bound : Node_Id;
2217 -- A tree node representing the low bound of the result (of type Ityp).
2218 -- This is either an integer literal node, or an identifier reference to
2219 -- a constant entity initialized to the appropriate value.
2221 Last_Opnd_High_Bound : Node_Id;
2222 -- A tree node representing the high bound of the last operand. This
2223 -- need only be set if the result could be null. It is used for the
2224 -- special case of setting the right high bound for a null result.
2225 -- This is of type Ityp.
2227 High_Bound : Node_Id;
2228 -- A tree node representing the high bound of the result (of type Ityp)
2231 -- Result of the concatenation (of type Ityp)
2233 function To_Artyp (X : Node_Id) return Node_Id;
2234 -- Given a node of type Ityp, returns the corresponding value of type
2235 -- Artyp. For non-enumeration types, this is a plain integer conversion.
2236 -- For enum types, the Pos of the value is returned.
2238 function To_Ityp (X : Node_Id) return Node_Id;
2239 -- The inverse function (uses Val in the case of enumeration types)
2241 Known_Non_Null_Operand_Seen : Boolean;
2242 -- Set True during generation of the assignements of operands into
2243 -- result once an operand known to be non-null has been seen.
2249 function To_Artyp (X : Node_Id) return Node_Id is
2251 if Ityp = Base_Type (Artyp) then
2254 elsif Is_Enumeration_Type (Ityp) then
2256 Make_Attribute_Reference (Loc,
2257 Prefix => New_Occurrence_Of (Ityp, Loc),
2258 Attribute_Name => Name_Pos,
2259 Expressions => New_List (X));
2262 return Convert_To (Artyp, X);
2270 function To_Ityp (X : Node_Id) return Node_Id is
2272 if Is_Enumeration_Type (Ityp) then
2274 Make_Attribute_Reference (Loc,
2275 Prefix => New_Occurrence_Of (Ityp, Loc),
2276 Attribute_Name => Name_Val,
2277 Expressions => New_List (X));
2279 -- Case where we will do a type conversion
2282 if Ityp = Base_Type (Artyp) then
2285 return Convert_To (Ityp, X);
2290 -- Local Declarations
2292 Opnd_Typ : Entity_Id;
2299 Saved_In_Inlined_Body : Boolean;
2302 Aggr_Length (0) := Make_Integer_Literal (Loc, 0);
2304 -- Choose an appropriate computational type
2306 -- We will be doing calculations of lengths and bounds in this routine
2307 -- and computing one from the other in some cases, e.g. getting the high
2308 -- bound by adding the length-1 to the low bound.
2310 -- We can't just use the index type, or even its base type for this
2311 -- purpose for two reasons. First it might be an enumeration type which
2312 -- is not suitable fo computations of any kind, and second it may simply
2313 -- not have enough range. For example if the index type is -128..+127
2314 -- then lengths can be up to 256, which is out of range of the type.
2316 -- For enumeration types, we can simply use Standard_Integer, this is
2317 -- sufficient since the actual number of enumeration literals cannot
2318 -- possibly exceed the range of integer (remember we will be doing the
2319 -- arithmetic with POS values, not representation values).
2321 if Is_Enumeration_Type (Ityp) then
2322 Artyp := Standard_Integer;
2324 -- For modular types, we use a 32-bit modular type for types whose size
2325 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
2326 -- identity type, and for larger unsigned types we use 64-bits.
2328 elsif Is_Modular_Integer_Type (Ityp) then
2329 if RM_Size (Ityp) < RM_Size (Standard_Unsigned) then
2330 Artyp := Standard_Unsigned;
2331 elsif RM_Size (Ityp) = RM_Size (Standard_Unsigned) then
2334 Artyp := RTE (RE_Long_Long_Unsigned);
2337 -- Similar treatment for signed types
2340 if RM_Size (Ityp) < RM_Size (Standard_Integer) then
2341 Artyp := Standard_Integer;
2342 elsif RM_Size (Ityp) = RM_Size (Standard_Integer) then
2345 Artyp := Standard_Long_Long_Integer;
2349 -- Go through operands setting up the above arrays
2353 Opnd := Remove_Head (Opnds);
2354 Opnd_Typ := Etype (Opnd);
2356 -- The parent got messed up when we put the operands in a list,
2357 -- so now put back the proper parent for the saved operand.
2359 Set_Parent (Opnd, Parent (Cnode));
2361 -- Set will be True when we have setup one entry in the array
2365 -- Singleton element (or character literal) case
2367 if Base_Type (Opnd_Typ) = Ctyp then
2369 Operands (NN) := Opnd;
2370 Is_Fixed_Length (NN) := True;
2371 Fixed_Length (NN) := Uint_1;
2372 Result_May_Be_Null := False;
2374 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
2375 -- since we know that the result cannot be null).
2377 Opnd_Low_Bound (NN) :=
2378 Make_Attribute_Reference (Loc,
2379 Prefix => New_Reference_To (Istyp, Loc),
2380 Attribute_Name => Name_First);
2384 -- String literal case (can only occur for strings of course)
2386 elsif Nkind (Opnd) = N_String_Literal then
2387 Len := String_Literal_Length (Opnd_Typ);
2390 Result_May_Be_Null := False;
2393 -- Capture last operand high bound if result could be null
2395 if J = N and then Result_May_Be_Null then
2396 Last_Opnd_High_Bound :=
2399 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ)),
2400 Right_Opnd => Make_Integer_Literal (Loc, 1));
2403 -- Skip null string literal
2405 if J < N and then Len = 0 then
2410 Operands (NN) := Opnd;
2411 Is_Fixed_Length (NN) := True;
2413 -- Set length and bounds
2415 Fixed_Length (NN) := Len;
2417 Opnd_Low_Bound (NN) :=
2418 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ));
2425 -- Check constrained case with known bounds
2427 if Is_Constrained (Opnd_Typ) then
2429 Index : constant Node_Id := First_Index (Opnd_Typ);
2430 Indx_Typ : constant Entity_Id := Etype (Index);
2431 Lo : constant Node_Id := Type_Low_Bound (Indx_Typ);
2432 Hi : constant Node_Id := Type_High_Bound (Indx_Typ);
2435 -- Fixed length constrained array type with known at compile
2436 -- time bounds is last case of fixed length operand.
2438 if Compile_Time_Known_Value (Lo)
2440 Compile_Time_Known_Value (Hi)
2443 Loval : constant Uint := Expr_Value (Lo);
2444 Hival : constant Uint := Expr_Value (Hi);
2445 Len : constant Uint :=
2446 UI_Max (Hival - Loval + 1, Uint_0);
2450 Result_May_Be_Null := False;
2453 -- Capture last operand bound if result could be null
2455 if J = N and then Result_May_Be_Null then
2456 Last_Opnd_High_Bound :=
2458 Make_Integer_Literal (Loc,
2459 Intval => Expr_Value (Hi)));
2462 -- Exclude null length case unless last operand
2464 if J < N and then Len = 0 then
2469 Operands (NN) := Opnd;
2470 Is_Fixed_Length (NN) := True;
2471 Fixed_Length (NN) := Len;
2473 Opnd_Low_Bound (NN) := To_Ityp (
2474 Make_Integer_Literal (Loc,
2475 Intval => Expr_Value (Lo)));
2483 -- All cases where the length is not known at compile time, or the
2484 -- special case of an operand which is known to be null but has a
2485 -- lower bound other than 1 or is other than a string type.
2490 -- Capture operand bounds
2492 Opnd_Low_Bound (NN) :=
2493 Make_Attribute_Reference (Loc,
2495 Duplicate_Subexpr (Opnd, Name_Req => True),
2496 Attribute_Name => Name_First);
2498 if J = N and Result_May_Be_Null then
2499 Last_Opnd_High_Bound :=
2501 Make_Attribute_Reference (Loc,
2503 Duplicate_Subexpr (Opnd, Name_Req => True),
2504 Attribute_Name => Name_Last));
2507 -- Capture length of operand in entity
2509 Operands (NN) := Opnd;
2510 Is_Fixed_Length (NN) := False;
2513 Make_Defining_Identifier (Loc,
2514 Chars => New_Internal_Name ('L'));
2516 Insert_Action (Cnode,
2517 Make_Object_Declaration (Loc,
2518 Defining_Identifier => Var_Length (NN),
2519 Constant_Present => True,
2521 Object_Definition =>
2522 New_Occurrence_Of (Artyp, Loc),
2525 Make_Attribute_Reference (Loc,
2527 Duplicate_Subexpr (Opnd, Name_Req => True),
2528 Attribute_Name => Name_Length)),
2530 Suppress => All_Checks);
2534 -- Set next entry in aggregate length array
2536 -- For first entry, make either integer literal for fixed length
2537 -- or a reference to the saved length for variable length.
2540 if Is_Fixed_Length (1) then
2542 Make_Integer_Literal (Loc,
2543 Intval => Fixed_Length (1));
2546 New_Reference_To (Var_Length (1), Loc);
2549 -- If entry is fixed length and only fixed lengths so far, make
2550 -- appropriate new integer literal adding new length.
2552 elsif Is_Fixed_Length (NN)
2553 and then Nkind (Aggr_Length (NN - 1)) = N_Integer_Literal
2556 Make_Integer_Literal (Loc,
2557 Intval => Fixed_Length (NN) + Intval (Aggr_Length (NN - 1)));
2559 -- All other cases, construct an addition node for the length and
2560 -- create an entity initialized to this length.
2564 Make_Defining_Identifier (Loc,
2565 Chars => New_Internal_Name ('L'));
2567 if Is_Fixed_Length (NN) then
2568 Clen := Make_Integer_Literal (Loc, Fixed_Length (NN));
2570 Clen := New_Reference_To (Var_Length (NN), Loc);
2573 Insert_Action (Cnode,
2574 Make_Object_Declaration (Loc,
2575 Defining_Identifier => Ent,
2576 Constant_Present => True,
2578 Object_Definition =>
2579 New_Occurrence_Of (Artyp, Loc),
2583 Left_Opnd => New_Copy (Aggr_Length (NN - 1)),
2584 Right_Opnd => Clen)),
2586 Suppress => All_Checks);
2588 Aggr_Length (NN) := Make_Identifier (Loc, Chars => Chars (Ent));
2595 -- If we have only skipped null operands, return the last operand
2602 -- If we have only one non-null operand, return it and we are done.
2603 -- There is one case in which this cannot be done, and that is when
2604 -- the sole operand is of the element type, in which case it must be
2605 -- converted to an array, and the easiest way of doing that is to go
2606 -- through the normal general circuit.
2609 and then Base_Type (Etype (Operands (1))) /= Ctyp
2611 Result := Operands (1);
2615 -- Cases where we have a real concatenation
2617 -- Next step is to find the low bound for the result array that we
2618 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
2620 -- If the ultimate ancestor of the index subtype is a constrained array
2621 -- definition, then the lower bound is that of the index subtype as
2622 -- specified by (RM 4.5.3(6)).
2624 -- The right test here is to go to the root type, and then the ultimate
2625 -- ancestor is the first subtype of this root type.
2627 if Is_Constrained (First_Subtype (Root_Type (Atyp))) then
2629 Make_Attribute_Reference (Loc,
2631 New_Occurrence_Of (First_Subtype (Root_Type (Atyp)), Loc),
2632 Attribute_Name => Name_First);
2634 -- If the first operand in the list has known length we know that
2635 -- the lower bound of the result is the lower bound of this operand.
2637 elsif Is_Fixed_Length (1) then
2638 Low_Bound := Opnd_Low_Bound (1);
2640 -- OK, we don't know the lower bound, we have to build a horrible
2641 -- expression actions node of the form
2643 -- if Cond1'Length /= 0 then
2646 -- if Opnd2'Length /= 0 then
2651 -- The nesting ends either when we hit an operand whose length is known
2652 -- at compile time, or on reaching the last operand, whose low bound we
2653 -- take unconditionally whether or not it is null. It's easiest to do
2654 -- this with a recursive procedure:
2658 function Get_Known_Bound (J : Nat) return Node_Id;
2659 -- Returns the lower bound determined by operands J .. NN
2661 ---------------------
2662 -- Get_Known_Bound --
2663 ---------------------
2665 function Get_Known_Bound (J : Nat) return Node_Id is
2667 if Is_Fixed_Length (J) or else J = NN then
2668 return New_Copy (Opnd_Low_Bound (J));
2672 Make_Conditional_Expression (Loc,
2673 Expressions => New_List (
2676 Left_Opnd => New_Reference_To (Var_Length (J), Loc),
2677 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2679 New_Copy (Opnd_Low_Bound (J)),
2680 Get_Known_Bound (J + 1)));
2682 end Get_Known_Bound;
2686 Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('L'));
2688 Insert_Action (Cnode,
2689 Make_Object_Declaration (Loc,
2690 Defining_Identifier => Ent,
2691 Constant_Present => True,
2692 Object_Definition => New_Occurrence_Of (Ityp, Loc),
2693 Expression => Get_Known_Bound (1)),
2694 Suppress => All_Checks);
2696 Low_Bound := New_Reference_To (Ent, Loc);
2700 -- Now we can safely compute the upper bound, normally
2701 -- Low_Bound + Length - 1.
2706 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2708 Make_Op_Subtract (Loc,
2709 Left_Opnd => New_Copy (Aggr_Length (NN)),
2710 Right_Opnd => Make_Integer_Literal (Loc, 1))));
2712 -- Now force overflow checking on High_Bound
2714 Activate_Overflow_Check (High_Bound);
2716 -- Handle the exceptional case where the result is null, in which case
2717 -- case the bounds come from the last operand (so that we get the proper
2718 -- bounds if the last operand is super-flat).
2720 if Result_May_Be_Null then
2722 Make_Conditional_Expression (Loc,
2723 Expressions => New_List (
2725 Left_Opnd => New_Copy (Aggr_Length (NN)),
2726 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2727 Last_Opnd_High_Bound,
2731 -- Now we construct an array object with appropriate bounds
2734 Make_Defining_Identifier (Loc,
2735 Chars => New_Internal_Name ('S'));
2737 -- Kludge! Kludge! ???
2738 -- If the bound is statically known to be out of range, we do not want
2739 -- to abort, we want a warning and a runtime constraint error, so we
2740 -- pretend this comes from an inlined body (otherwise a static out
2741 -- of range value would be an illegality).
2743 -- This is horrible, we really must find a better way ???
2745 Saved_In_Inlined_Body := In_Inlined_Body;
2746 In_Inlined_Body := True;
2748 Insert_Action (Cnode,
2749 Make_Object_Declaration (Loc,
2750 Defining_Identifier => Ent,
2751 Object_Definition =>
2752 Make_Subtype_Indication (Loc,
2753 Subtype_Mark => New_Occurrence_Of (Atyp, Loc),
2755 Make_Index_Or_Discriminant_Constraint (Loc,
2756 Constraints => New_List (
2758 Low_Bound => Low_Bound,
2759 High_Bound => High_Bound))))),
2760 Suppress => All_Checks);
2762 In_Inlined_Body := Saved_In_Inlined_Body;
2764 -- Catch the static out of range case now
2766 if Raises_Constraint_Error (High_Bound) then
2767 raise Concatenation_Error;
2770 -- Now we will generate the assignments to do the actual concatenation
2772 Known_Non_Null_Operand_Seen := False;
2774 for J in 1 .. NN loop
2776 Lo : constant Node_Id :=
2778 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2779 Right_Opnd => Aggr_Length (J - 1));
2781 Hi : constant Node_Id :=
2783 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2785 Make_Op_Subtract (Loc,
2786 Left_Opnd => Aggr_Length (J),
2787 Right_Opnd => Make_Integer_Literal (Loc, 1)));
2790 -- Singleton case, simple assignment
2792 if Base_Type (Etype (Operands (J))) = Ctyp then
2793 Known_Non_Null_Operand_Seen := True;
2794 Insert_Action (Cnode,
2795 Make_Assignment_Statement (Loc,
2797 Make_Indexed_Component (Loc,
2798 Prefix => New_Occurrence_Of (Ent, Loc),
2799 Expressions => New_List (To_Ityp (Lo))),
2800 Expression => Operands (J)),
2801 Suppress => All_Checks);
2803 -- Array case, slice assignment, skipped when argument is fixed
2804 -- length and known to be null.
2806 elsif (not Is_Fixed_Length (J)) or else (Fixed_Length (J) > 0) then
2809 Make_Assignment_Statement (Loc,
2813 New_Occurrence_Of (Ent, Loc),
2816 Low_Bound => To_Ityp (Lo),
2817 High_Bound => To_Ityp (Hi))),
2818 Expression => Operands (J));
2820 if Is_Fixed_Length (J) then
2821 Known_Non_Null_Operand_Seen := True;
2823 elsif not Known_Non_Null_Operand_Seen then
2825 -- Here if operand length is not statically known and no
2826 -- operand known to be non-null has been processed yet.
2827 -- If operand length is 0, we do not need to perform the
2828 -- assignment, and we must avoid the evaluation of the
2829 -- high bound of the slice, since it may underflow if the
2830 -- low bound is Ityp'First.
2833 Make_Implicit_If_Statement (Cnode,
2837 New_Occurrence_Of (Var_Length (J), Loc),
2838 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2842 Insert_Action (Cnode, Assign, Suppress => All_Checks);
2848 -- Finally we build the result, which is a reference to the array object
2850 Result := New_Reference_To (Ent, Loc);
2853 Rewrite (Cnode, Result);
2854 Analyze_And_Resolve (Cnode, Atyp);
2857 when Concatenation_Error =>
2859 -- Kill warning generated for the declaration of the static out of
2860 -- range high bound, and instead generate a Constraint_Error with
2861 -- an appropriate specific message.
2863 Kill_Dead_Code (Declaration_Node (Entity (High_Bound)));
2864 Apply_Compile_Time_Constraint_Error
2866 Msg => "concatenation result upper bound out of range?",
2867 Reason => CE_Range_Check_Failed);
2868 -- Set_Etype (Cnode, Atyp);
2869 end Expand_Concatenate;
2871 ------------------------
2872 -- Expand_N_Allocator --
2873 ------------------------
2875 procedure Expand_N_Allocator (N : Node_Id) is
2876 PtrT : constant Entity_Id := Etype (N);
2877 Dtyp : constant Entity_Id := Designated_Type (PtrT);
2878 Etyp : constant Entity_Id := Etype (Expression (N));
2879 Loc : constant Source_Ptr := Sloc (N);
2884 procedure Complete_Coextension_Finalization;
2885 -- Generate finalization calls for all nested coextensions of N. This
2886 -- routine may allocate list controllers if necessary.
2888 procedure Rewrite_Coextension (N : Node_Id);
2889 -- Static coextensions have the same lifetime as the entity they
2890 -- constrain. Such occurrences can be rewritten as aliased objects
2891 -- and their unrestricted access used instead of the coextension.
2893 ---------------------------------------
2894 -- Complete_Coextension_Finalization --
2895 ---------------------------------------
2897 procedure Complete_Coextension_Finalization is
2899 Coext_Elmt : Elmt_Id;
2903 function Inside_A_Return_Statement (N : Node_Id) return Boolean;
2904 -- Determine whether node N is part of a return statement
2906 function Needs_Initialization_Call (N : Node_Id) return Boolean;
2907 -- Determine whether node N is a subtype indicator allocator which
2908 -- acts a coextension. Such coextensions need initialization.
2910 -------------------------------
2911 -- Inside_A_Return_Statement --
2912 -------------------------------
2914 function Inside_A_Return_Statement (N : Node_Id) return Boolean is
2919 while Present (P) loop
2921 (P, N_Extended_Return_Statement, N_Simple_Return_Statement)
2925 -- Stop the traversal when we reach a subprogram body
2927 elsif Nkind (P) = N_Subprogram_Body then
2935 end Inside_A_Return_Statement;
2937 -------------------------------
2938 -- Needs_Initialization_Call --
2939 -------------------------------
2941 function Needs_Initialization_Call (N : Node_Id) return Boolean is
2945 if Nkind (N) = N_Explicit_Dereference
2946 and then Nkind (Prefix (N)) = N_Identifier
2947 and then Nkind (Parent (Entity (Prefix (N)))) =
2948 N_Object_Declaration
2950 Obj_Decl := Parent (Entity (Prefix (N)));
2953 Present (Expression (Obj_Decl))
2954 and then Nkind (Expression (Obj_Decl)) = N_Allocator
2955 and then Nkind (Expression (Expression (Obj_Decl))) /=
2956 N_Qualified_Expression;
2960 end Needs_Initialization_Call;
2962 -- Start of processing for Complete_Coextension_Finalization
2965 -- When a coextension root is inside a return statement, we need to
2966 -- use the finalization chain of the function's scope. This does not
2967 -- apply for controlled named access types because in those cases we
2968 -- can use the finalization chain of the type itself.
2970 if Inside_A_Return_Statement (N)
2972 (Ekind (PtrT) = E_Anonymous_Access_Type
2974 (Ekind (PtrT) = E_Access_Type
2975 and then No (Associated_Final_Chain (PtrT))))
2979 Outer_S : Entity_Id;
2980 S : Entity_Id := Current_Scope;
2983 while Present (S) and then S /= Standard_Standard loop
2984 if Ekind (S) = E_Function then
2985 Outer_S := Scope (S);
2987 -- Retrieve the declaration of the body
2989 Decl := Parent (Parent (
2990 Corresponding_Body (Parent (Parent (S)))));
2997 -- Push the scope of the function body since we are inserting
2998 -- the list before the body, but we are currently in the body
2999 -- itself. Override the finalization list of PtrT since the
3000 -- finalization context is now different.
3002 Push_Scope (Outer_S);
3003 Build_Final_List (Decl, PtrT);
3007 -- The root allocator may not be controlled, but it still needs a
3008 -- finalization list for all nested coextensions.
3010 elsif No (Associated_Final_Chain (PtrT)) then
3011 Build_Final_List (N, PtrT);
3015 Make_Selected_Component (Loc,
3017 New_Reference_To (Associated_Final_Chain (PtrT), Loc),
3019 Make_Identifier (Loc, Name_F));
3021 Coext_Elmt := First_Elmt (Coextensions (N));
3022 while Present (Coext_Elmt) loop
3023 Coext := Node (Coext_Elmt);
3028 if Nkind (Coext) = N_Identifier then
3030 Make_Unchecked_Type_Conversion (Loc,
3031 Subtype_Mark => New_Reference_To (Etype (Coext), Loc),
3033 Make_Explicit_Dereference (Loc,
3034 Prefix => New_Copy_Tree (Coext)));
3036 Ref := New_Copy_Tree (Coext);
3039 -- No initialization call if not allowed
3041 Check_Restriction (No_Default_Initialization, N);
3043 if not Restriction_Active (No_Default_Initialization) then
3047 -- attach_to_final_list (Ref, Flist, 2)
3049 if Needs_Initialization_Call (Coext) then
3053 Typ => Etype (Coext),
3055 With_Attach => Make_Integer_Literal (Loc, Uint_2)));
3058 -- attach_to_final_list (Ref, Flist, 2)
3064 Flist_Ref => New_Copy_Tree (Flist),
3065 With_Attach => Make_Integer_Literal (Loc, Uint_2)));
3069 Next_Elmt (Coext_Elmt);
3071 end Complete_Coextension_Finalization;
3073 -------------------------
3074 -- Rewrite_Coextension --
3075 -------------------------
3077 procedure Rewrite_Coextension (N : Node_Id) is
3078 Temp : constant Node_Id :=
3079 Make_Defining_Identifier (Loc,
3080 New_Internal_Name ('C'));
3083 -- Cnn : aliased Etyp;
3085 Decl : constant Node_Id :=
3086 Make_Object_Declaration (Loc,
3087 Defining_Identifier => Temp,
3088 Aliased_Present => True,
3089 Object_Definition =>
3090 New_Occurrence_Of (Etyp, Loc));
3094 if Nkind (Expression (N)) = N_Qualified_Expression then
3095 Set_Expression (Decl, Expression (Expression (N)));
3098 -- Find the proper insertion node for the declaration
3101 while Present (Nod) loop
3102 exit when Nkind (Nod) in N_Statement_Other_Than_Procedure_Call
3103 or else Nkind (Nod) = N_Procedure_Call_Statement
3104 or else Nkind (Nod) in N_Declaration;
3105 Nod := Parent (Nod);
3108 Insert_Before (Nod, Decl);
3112 Make_Attribute_Reference (Loc,
3113 Prefix => New_Occurrence_Of (Temp, Loc),
3114 Attribute_Name => Name_Unrestricted_Access));
3116 Analyze_And_Resolve (N, PtrT);
3117 end Rewrite_Coextension;
3119 -- Start of processing for Expand_N_Allocator
3122 -- RM E.2.3(22). We enforce that the expected type of an allocator
3123 -- shall not be a remote access-to-class-wide-limited-private type
3125 -- Why is this being done at expansion time, seems clearly wrong ???
3127 Validate_Remote_Access_To_Class_Wide_Type (N);
3129 -- Set the Storage Pool
3131 Set_Storage_Pool (N, Associated_Storage_Pool (Root_Type (PtrT)));
3133 if Present (Storage_Pool (N)) then
3134 if Is_RTE (Storage_Pool (N), RE_SS_Pool) then
3135 if VM_Target = No_VM then
3136 Set_Procedure_To_Call (N, RTE (RE_SS_Allocate));
3139 elsif Is_Class_Wide_Type (Etype (Storage_Pool (N))) then
3140 Set_Procedure_To_Call (N, RTE (RE_Allocate_Any));
3143 Set_Procedure_To_Call (N,
3144 Find_Prim_Op (Etype (Storage_Pool (N)), Name_Allocate));
3148 -- Under certain circumstances we can replace an allocator by an access
3149 -- to statically allocated storage. The conditions, as noted in AARM
3150 -- 3.10 (10c) are as follows:
3152 -- Size and initial value is known at compile time
3153 -- Access type is access-to-constant
3155 -- The allocator is not part of a constraint on a record component,
3156 -- because in that case the inserted actions are delayed until the
3157 -- record declaration is fully analyzed, which is too late for the
3158 -- analysis of the rewritten allocator.
3160 if Is_Access_Constant (PtrT)
3161 and then Nkind (Expression (N)) = N_Qualified_Expression
3162 and then Compile_Time_Known_Value (Expression (Expression (N)))
3163 and then Size_Known_At_Compile_Time (Etype (Expression
3165 and then not Is_Record_Type (Current_Scope)
3167 -- Here we can do the optimization. For the allocator
3171 -- We insert an object declaration
3173 -- Tnn : aliased x := y;
3175 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
3176 -- marked as requiring static allocation.
3179 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
3181 Desig := Subtype_Mark (Expression (N));
3183 -- If context is constrained, use constrained subtype directly,
3184 -- so that the constant is not labelled as having a nominally
3185 -- unconstrained subtype.
3187 if Entity (Desig) = Base_Type (Dtyp) then
3188 Desig := New_Occurrence_Of (Dtyp, Loc);
3192 Make_Object_Declaration (Loc,
3193 Defining_Identifier => Temp,
3194 Aliased_Present => True,
3195 Constant_Present => Is_Access_Constant (PtrT),
3196 Object_Definition => Desig,
3197 Expression => Expression (Expression (N))));
3200 Make_Attribute_Reference (Loc,
3201 Prefix => New_Occurrence_Of (Temp, Loc),
3202 Attribute_Name => Name_Unrestricted_Access));
3204 Analyze_And_Resolve (N, PtrT);
3206 -- We set the variable as statically allocated, since we don't want
3207 -- it going on the stack of the current procedure!
3209 Set_Is_Statically_Allocated (Temp);
3213 -- Same if the allocator is an access discriminant for a local object:
3214 -- instead of an allocator we create a local value and constrain the
3215 -- the enclosing object with the corresponding access attribute.
3217 if Is_Static_Coextension (N) then
3218 Rewrite_Coextension (N);
3222 -- The current allocator creates an object which may contain nested
3223 -- coextensions. Use the current allocator's finalization list to
3224 -- generate finalization call for all nested coextensions.
3226 if Is_Coextension_Root (N) then
3227 Complete_Coextension_Finalization;
3230 -- Handle case of qualified expression (other than optimization above)
3232 if Nkind (Expression (N)) = N_Qualified_Expression then
3233 Expand_Allocator_Expression (N);
3237 -- If the allocator is for a type which requires initialization, and
3238 -- there is no initial value (i.e. operand is a subtype indication
3239 -- rather than a qualified expression), then we must generate a call to
3240 -- the initialization routine using an expressions action node:
3242 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
3244 -- Here ptr_T is the pointer type for the allocator, and T is the
3245 -- subtype of the allocator. A special case arises if the designated
3246 -- type of the access type is a task or contains tasks. In this case
3247 -- the call to Init (Temp.all ...) is replaced by code that ensures
3248 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
3249 -- for details). In addition, if the type T is a task T, then the
3250 -- first argument to Init must be converted to the task record type.
3253 T : constant Entity_Id := Entity (Expression (N));
3261 Temp_Decl : Node_Id;
3262 Temp_Type : Entity_Id;
3263 Attach_Level : Uint;
3266 if No_Initialization (N) then
3269 -- Case of no initialization procedure present
3271 elsif not Has_Non_Null_Base_Init_Proc (T) then
3273 -- Case of simple initialization required
3275 if Needs_Simple_Initialization (T) then
3276 Check_Restriction (No_Default_Initialization, N);
3277 Rewrite (Expression (N),
3278 Make_Qualified_Expression (Loc,
3279 Subtype_Mark => New_Occurrence_Of (T, Loc),
3280 Expression => Get_Simple_Init_Val (T, N)));
3282 Analyze_And_Resolve (Expression (Expression (N)), T);
3283 Analyze_And_Resolve (Expression (N), T);
3284 Set_Paren_Count (Expression (Expression (N)), 1);
3285 Expand_N_Allocator (N);
3287 -- No initialization required
3293 -- Case of initialization procedure present, must be called
3296 Check_Restriction (No_Default_Initialization, N);
3298 if not Restriction_Active (No_Default_Initialization) then
3299 Init := Base_Init_Proc (T);
3301 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
3303 -- Construct argument list for the initialization routine call
3306 Make_Explicit_Dereference (Loc,
3307 Prefix => New_Reference_To (Temp, Loc));
3308 Set_Assignment_OK (Arg1);
3311 -- The initialization procedure expects a specific type. if the
3312 -- context is access to class wide, indicate that the object
3313 -- being allocated has the right specific type.
3315 if Is_Class_Wide_Type (Dtyp) then
3316 Arg1 := Unchecked_Convert_To (T, Arg1);
3319 -- If designated type is a concurrent type or if it is private
3320 -- type whose definition is a concurrent type, the first
3321 -- argument in the Init routine has to be unchecked conversion
3322 -- to the corresponding record type. If the designated type is
3323 -- a derived type, we also convert the argument to its root
3326 if Is_Concurrent_Type (T) then
3328 Unchecked_Convert_To (Corresponding_Record_Type (T), Arg1);
3330 elsif Is_Private_Type (T)
3331 and then Present (Full_View (T))
3332 and then Is_Concurrent_Type (Full_View (T))
3335 Unchecked_Convert_To
3336 (Corresponding_Record_Type (Full_View (T)), Arg1);
3338 elsif Etype (First_Formal (Init)) /= Base_Type (T) then
3340 Ftyp : constant Entity_Id := Etype (First_Formal (Init));
3342 Arg1 := OK_Convert_To (Etype (Ftyp), Arg1);
3343 Set_Etype (Arg1, Ftyp);
3347 Args := New_List (Arg1);
3349 -- For the task case, pass the Master_Id of the access type as
3350 -- the value of the _Master parameter, and _Chain as the value
3351 -- of the _Chain parameter (_Chain will be defined as part of
3352 -- the generated code for the allocator).
3354 -- In Ada 2005, the context may be a function that returns an
3355 -- anonymous access type. In that case the Master_Id has been
3356 -- created when expanding the function declaration.
3358 if Has_Task (T) then
3359 if No (Master_Id (Base_Type (PtrT))) then
3361 -- If we have a non-library level task with restriction
3362 -- No_Task_Hierarchy set, then no point in expanding.
3364 if not Is_Library_Level_Entity (T)
3365 and then Restriction_Active (No_Task_Hierarchy)
3370 -- The designated type was an incomplete type, and the
3371 -- access type did not get expanded. Salvage it now.
3373 pragma Assert (Present (Parent (Base_Type (PtrT))));
3374 Expand_N_Full_Type_Declaration
3375 (Parent (Base_Type (PtrT)));
3378 -- If the context of the allocator is a declaration or an
3379 -- assignment, we can generate a meaningful image for it,
3380 -- even though subsequent assignments might remove the
3381 -- connection between task and entity. We build this image
3382 -- when the left-hand side is a simple variable, a simple
3383 -- indexed assignment or a simple selected component.
3385 if Nkind (Parent (N)) = N_Assignment_Statement then
3387 Nam : constant Node_Id := Name (Parent (N));
3390 if Is_Entity_Name (Nam) then
3392 Build_Task_Image_Decls
3395 (Entity (Nam), Sloc (Nam)), T);
3398 (Nam, N_Indexed_Component, N_Selected_Component)
3399 and then Is_Entity_Name (Prefix (Nam))
3402 Build_Task_Image_Decls
3403 (Loc, Nam, Etype (Prefix (Nam)));
3405 Decls := Build_Task_Image_Decls (Loc, T, T);
3409 elsif Nkind (Parent (N)) = N_Object_Declaration then
3411 Build_Task_Image_Decls
3412 (Loc, Defining_Identifier (Parent (N)), T);
3415 Decls := Build_Task_Image_Decls (Loc, T, T);
3420 (Master_Id (Base_Type (Root_Type (PtrT))), Loc));
3421 Append_To (Args, Make_Identifier (Loc, Name_uChain));
3423 Decl := Last (Decls);
3425 New_Occurrence_Of (Defining_Identifier (Decl), Loc));
3427 -- Has_Task is false, Decls not used
3433 -- Add discriminants if discriminated type
3436 Dis : Boolean := False;
3440 if Has_Discriminants (T) then
3444 elsif Is_Private_Type (T)
3445 and then Present (Full_View (T))
3446 and then Has_Discriminants (Full_View (T))
3449 Typ := Full_View (T);
3454 -- If the allocated object will be constrained by the
3455 -- default values for discriminants, then build a subtype
3456 -- with those defaults, and change the allocated subtype
3457 -- to that. Note that this happens in fewer cases in Ada
3460 if not Is_Constrained (Typ)
3461 and then Present (Discriminant_Default_Value
3462 (First_Discriminant (Typ)))
3463 and then (Ada_Version < Ada_05
3465 not Has_Constrained_Partial_View (Typ))
3467 Typ := Build_Default_Subtype (Typ, N);
3468 Set_Expression (N, New_Reference_To (Typ, Loc));
3471 Discr := First_Elmt (Discriminant_Constraint (Typ));
3472 while Present (Discr) loop
3473 Nod := Node (Discr);
3474 Append (New_Copy_Tree (Node (Discr)), Args);
3476 -- AI-416: when the discriminant constraint is an
3477 -- anonymous access type make sure an accessibility
3478 -- check is inserted if necessary (3.10.2(22.q/2))
3480 if Ada_Version >= Ada_05
3482 Ekind (Etype (Nod)) = E_Anonymous_Access_Type
3484 Apply_Accessibility_Check
3485 (Nod, Typ, Insert_Node => Nod);
3493 -- We set the allocator as analyzed so that when we analyze the
3494 -- expression actions node, we do not get an unwanted recursive
3495 -- expansion of the allocator expression.
3497 Set_Analyzed (N, True);
3498 Nod := Relocate_Node (N);
3500 -- Here is the transformation:
3502 -- output: Temp : constant ptr_T := new T;
3503 -- Init (Temp.all, ...);
3504 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
3505 -- <CTRL> Initialize (Finalizable (Temp.all));
3507 -- Here ptr_T is the pointer type for the allocator, and is the
3508 -- subtype of the allocator.
3511 Make_Object_Declaration (Loc,
3512 Defining_Identifier => Temp,
3513 Constant_Present => True,
3514 Object_Definition => New_Reference_To (Temp_Type, Loc),
3517 Set_Assignment_OK (Temp_Decl);
3518 Insert_Action (N, Temp_Decl, Suppress => All_Checks);
3520 -- If the designated type is a task type or contains tasks,
3521 -- create block to activate created tasks, and insert
3522 -- declaration for Task_Image variable ahead of call.
3524 if Has_Task (T) then
3526 L : constant List_Id := New_List;
3529 Build_Task_Allocate_Block (L, Nod, Args);
3531 Insert_List_Before (First (Declarations (Blk)), Decls);
3532 Insert_Actions (N, L);
3537 Make_Procedure_Call_Statement (Loc,
3538 Name => New_Reference_To (Init, Loc),
3539 Parameter_Associations => Args));
3542 if Needs_Finalization (T) then
3544 -- Postpone the generation of a finalization call for the
3545 -- current allocator if it acts as a coextension.
3547 if Is_Dynamic_Coextension (N) then
3548 if No (Coextensions (N)) then
3549 Set_Coextensions (N, New_Elmt_List);
3552 Append_Elmt (New_Copy_Tree (Arg1), Coextensions (N));
3556 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
3558 -- Anonymous access types created for access parameters
3559 -- are attached to an explicitly constructed controller,
3560 -- which ensures that they can be finalized properly,
3561 -- even if their deallocation might not happen. The list
3562 -- associated with the controller is doubly-linked. For
3563 -- other anonymous access types, the object may end up
3564 -- on the global final list which is singly-linked.
3565 -- Work needed for access discriminants in Ada 2005 ???
3567 if Ekind (PtrT) = E_Anonymous_Access_Type
3569 Nkind (Associated_Node_For_Itype (PtrT))
3570 not in N_Subprogram_Specification
3572 Attach_Level := Uint_1;
3574 Attach_Level := Uint_2;
3579 Ref => New_Copy_Tree (Arg1),
3582 With_Attach => Make_Integer_Literal (Loc,
3583 Intval => Attach_Level)));
3587 Rewrite (N, New_Reference_To (Temp, Loc));
3588 Analyze_And_Resolve (N, PtrT);
3593 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
3594 -- object that has been rewritten as a reference, we displace "this"
3595 -- to reference properly its secondary dispatch table.
3597 if Nkind (N) = N_Identifier
3598 and then Is_Interface (Dtyp)
3600 Displace_Allocator_Pointer (N);
3604 when RE_Not_Available =>
3606 end Expand_N_Allocator;
3608 -----------------------
3609 -- Expand_N_And_Then --
3610 -----------------------
3612 -- Expand into conditional expression if Actions present, and also deal
3613 -- with optimizing case of arguments being True or False.
3615 procedure Expand_N_And_Then (N : Node_Id) is
3616 Loc : constant Source_Ptr := Sloc (N);
3617 Typ : constant Entity_Id := Etype (N);
3618 Left : constant Node_Id := Left_Opnd (N);
3619 Right : constant Node_Id := Right_Opnd (N);
3623 -- Deal with non-standard booleans
3625 if Is_Boolean_Type (Typ) then
3626 Adjust_Condition (Left);
3627 Adjust_Condition (Right);
3628 Set_Etype (N, Standard_Boolean);
3631 -- Check for cases where left argument is known to be True or False
3633 if Compile_Time_Known_Value (Left) then
3635 -- If left argument is True, change (True and then Right) to Right.
3636 -- Any actions associated with Right will be executed unconditionally
3637 -- and can thus be inserted into the tree unconditionally.
3639 if Expr_Value_E (Left) = Standard_True then
3640 if Present (Actions (N)) then
3641 Insert_Actions (N, Actions (N));
3646 -- If left argument is False, change (False and then Right) to False.
3647 -- In this case we can forget the actions associated with Right,
3648 -- since they will never be executed.
3650 else pragma Assert (Expr_Value_E (Left) = Standard_False);
3651 Kill_Dead_Code (Right);
3652 Kill_Dead_Code (Actions (N));
3653 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
3656 Adjust_Result_Type (N, Typ);
3660 -- If Actions are present, we expand
3662 -- left and then right
3666 -- if left then right else false end
3668 -- with the actions becoming the Then_Actions of the conditional
3669 -- expression. This conditional expression is then further expanded
3670 -- (and will eventually disappear)
3672 if Present (Actions (N)) then
3673 Actlist := Actions (N);
3675 Make_Conditional_Expression (Loc,
3676 Expressions => New_List (
3679 New_Occurrence_Of (Standard_False, Loc))));
3681 Set_Then_Actions (N, Actlist);
3682 Analyze_And_Resolve (N, Standard_Boolean);
3683 Adjust_Result_Type (N, Typ);
3687 -- No actions present, check for cases of right argument True/False
3689 if Compile_Time_Known_Value (Right) then
3691 -- Change (Left and then True) to Left. Note that we know there are
3692 -- no actions associated with the True operand, since we just checked
3693 -- for this case above.
3695 if Expr_Value_E (Right) = Standard_True then
3698 -- Change (Left and then False) to False, making sure to preserve any
3699 -- side effects associated with the Left operand.
3701 else pragma Assert (Expr_Value_E (Right) = Standard_False);
3702 Remove_Side_Effects (Left);
3704 (N, New_Occurrence_Of (Standard_False, Loc));
3708 Adjust_Result_Type (N, Typ);
3709 end Expand_N_And_Then;
3711 -------------------------------------
3712 -- Expand_N_Conditional_Expression --
3713 -------------------------------------
3715 -- Expand into expression actions if then/else actions present
3717 procedure Expand_N_Conditional_Expression (N : Node_Id) is
3718 Loc : constant Source_Ptr := Sloc (N);
3719 Cond : constant Node_Id := First (Expressions (N));
3720 Thenx : constant Node_Id := Next (Cond);
3721 Elsex : constant Node_Id := Next (Thenx);
3722 Typ : constant Entity_Id := Etype (N);
3727 -- If either then or else actions are present, then given:
3729 -- if cond then then-expr else else-expr end
3731 -- we insert the following sequence of actions (using Insert_Actions):
3736 -- Cnn := then-expr;
3742 -- and replace the conditional expression by a reference to Cnn
3744 if Present (Then_Actions (N)) or else Present (Else_Actions (N)) then
3745 Cnn := Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
3748 Make_Implicit_If_Statement (N,
3749 Condition => Relocate_Node (Cond),
3751 Then_Statements => New_List (
3752 Make_Assignment_Statement (Sloc (Thenx),
3753 Name => New_Occurrence_Of (Cnn, Sloc (Thenx)),
3754 Expression => Relocate_Node (Thenx))),
3756 Else_Statements => New_List (
3757 Make_Assignment_Statement (Sloc (Elsex),
3758 Name => New_Occurrence_Of (Cnn, Sloc (Elsex)),
3759 Expression => Relocate_Node (Elsex))));
3761 Set_Assignment_OK (Name (First (Then_Statements (New_If))));
3762 Set_Assignment_OK (Name (First (Else_Statements (New_If))));
3764 if Present (Then_Actions (N)) then
3766 (First (Then_Statements (New_If)), Then_Actions (N));
3769 if Present (Else_Actions (N)) then
3771 (First (Else_Statements (New_If)), Else_Actions (N));
3774 Rewrite (N, New_Occurrence_Of (Cnn, Loc));
3777 Make_Object_Declaration (Loc,
3778 Defining_Identifier => Cnn,
3779 Object_Definition => New_Occurrence_Of (Typ, Loc)));
3781 Insert_Action (N, New_If);
3782 Analyze_And_Resolve (N, Typ);
3784 end Expand_N_Conditional_Expression;
3786 -----------------------------------
3787 -- Expand_N_Explicit_Dereference --
3788 -----------------------------------
3790 procedure Expand_N_Explicit_Dereference (N : Node_Id) is
3792 -- Insert explicit dereference call for the checked storage pool case
3794 Insert_Dereference_Action (Prefix (N));
3795 end Expand_N_Explicit_Dereference;
3801 procedure Expand_N_In (N : Node_Id) is
3802 Loc : constant Source_Ptr := Sloc (N);
3803 Rtyp : constant Entity_Id := Etype (N);
3804 Lop : constant Node_Id := Left_Opnd (N);
3805 Rop : constant Node_Id := Right_Opnd (N);
3806 Static : constant Boolean := Is_OK_Static_Expression (N);
3808 procedure Substitute_Valid_Check;
3809 -- Replaces node N by Lop'Valid. This is done when we have an explicit
3810 -- test for the left operand being in range of its subtype.
3812 ----------------------------
3813 -- Substitute_Valid_Check --
3814 ----------------------------
3816 procedure Substitute_Valid_Check is
3819 Make_Attribute_Reference (Loc,
3820 Prefix => Relocate_Node (Lop),
3821 Attribute_Name => Name_Valid));
3823 Analyze_And_Resolve (N, Rtyp);
3825 Error_Msg_N ("?explicit membership test may be optimized away", N);
3826 Error_Msg_N ("\?use ''Valid attribute instead", N);
3828 end Substitute_Valid_Check;
3830 -- Start of processing for Expand_N_In
3833 -- Check case of explicit test for an expression in range of its
3834 -- subtype. This is suspicious usage and we replace it with a 'Valid
3835 -- test and give a warning.
3837 if Is_Scalar_Type (Etype (Lop))
3838 and then Nkind (Rop) in N_Has_Entity
3839 and then Etype (Lop) = Entity (Rop)
3840 and then Comes_From_Source (N)
3841 and then VM_Target = No_VM
3843 Substitute_Valid_Check;
3847 -- Do validity check on operands
3849 if Validity_Checks_On and Validity_Check_Operands then
3850 Ensure_Valid (Left_Opnd (N));
3851 Validity_Check_Range (Right_Opnd (N));
3854 -- Case of explicit range
3856 if Nkind (Rop) = N_Range then
3858 Lo : constant Node_Id := Low_Bound (Rop);
3859 Hi : constant Node_Id := High_Bound (Rop);
3861 Ltyp : constant Entity_Id := Etype (Lop);
3863 Lo_Orig : constant Node_Id := Original_Node (Lo);
3864 Hi_Orig : constant Node_Id := Original_Node (Hi);
3866 Lcheck : Compare_Result;
3867 Ucheck : Compare_Result;
3869 Warn1 : constant Boolean :=
3870 Constant_Condition_Warnings
3871 and then Comes_From_Source (N)
3872 and then not In_Instance;
3873 -- This must be true for any of the optimization warnings, we
3874 -- clearly want to give them only for source with the flag on.
3875 -- We also skip these warnings in an instance since it may be
3876 -- the case that different instantiations have different ranges.
3878 Warn2 : constant Boolean :=
3880 and then Nkind (Original_Node (Rop)) = N_Range
3881 and then Is_Integer_Type (Etype (Lo));
3882 -- For the case where only one bound warning is elided, we also
3883 -- insist on an explicit range and an integer type. The reason is
3884 -- that the use of enumeration ranges including an end point is
3885 -- common, as is the use of a subtype name, one of whose bounds
3886 -- is the same as the type of the expression.
3889 -- If test is explicit x'first .. x'last, replace by valid check
3891 if Is_Scalar_Type (Ltyp)
3892 and then Nkind (Lo_Orig) = N_Attribute_Reference
3893 and then Attribute_Name (Lo_Orig) = Name_First
3894 and then Nkind (Prefix (Lo_Orig)) in N_Has_Entity
3895 and then Entity (Prefix (Lo_Orig)) = Ltyp
3896 and then Nkind (Hi_Orig) = N_Attribute_Reference
3897 and then Attribute_Name (Hi_Orig) = Name_Last
3898 and then Nkind (Prefix (Hi_Orig)) in N_Has_Entity
3899 and then Entity (Prefix (Hi_Orig)) = Ltyp
3900 and then Comes_From_Source (N)
3901 and then VM_Target = No_VM
3903 Substitute_Valid_Check;
3907 -- If bounds of type are known at compile time, and the end points
3908 -- are known at compile time and identical, this is another case
3909 -- for substituting a valid test. We only do this for discrete
3910 -- types, since it won't arise in practice for float types.
3912 if Comes_From_Source (N)
3913 and then Is_Discrete_Type (Ltyp)
3914 and then Compile_Time_Known_Value (Type_High_Bound (Ltyp))
3915 and then Compile_Time_Known_Value (Type_Low_Bound (Ltyp))
3916 and then Compile_Time_Known_Value (Lo)
3917 and then Compile_Time_Known_Value (Hi)
3918 and then Expr_Value (Type_High_Bound (Ltyp)) = Expr_Value (Hi)
3919 and then Expr_Value (Type_Low_Bound (Ltyp)) = Expr_Value (Lo)
3921 -- Kill warnings in instances, since they may be cases where we
3922 -- have a test in the generic that makes sense with some types
3923 -- and not with other types.
3925 and then not In_Instance
3927 Substitute_Valid_Check;
3931 -- If we have an explicit range, do a bit of optimization based
3932 -- on range analysis (we may be able to kill one or both checks).
3934 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => False);
3935 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => False);
3937 -- If either check is known to fail, replace result by False since
3938 -- the other check does not matter. Preserve the static flag for
3939 -- legality checks, because we are constant-folding beyond RM 4.9.
3941 if Lcheck = LT or else Ucheck = GT then
3943 Error_Msg_N ("?range test optimized away", N);
3944 Error_Msg_N ("\?value is known to be out of range", N);
3948 New_Reference_To (Standard_False, Loc));
3949 Analyze_And_Resolve (N, Rtyp);
3950 Set_Is_Static_Expression (N, Static);
3954 -- If both checks are known to succeed, replace result by True,
3955 -- since we know we are in range.
3957 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
3959 Error_Msg_N ("?range test optimized away", N);
3960 Error_Msg_N ("\?value is known to be in range", N);
3964 New_Reference_To (Standard_True, Loc));
3965 Analyze_And_Resolve (N, Rtyp);
3966 Set_Is_Static_Expression (N, Static);
3970 -- If lower bound check succeeds and upper bound check is not
3971 -- known to succeed or fail, then replace the range check with
3972 -- a comparison against the upper bound.
3974 elsif Lcheck in Compare_GE then
3975 if Warn2 and then not In_Instance then
3976 Error_Msg_N ("?lower bound test optimized away", Lo);
3977 Error_Msg_N ("\?value is known to be in range", Lo);
3983 Right_Opnd => High_Bound (Rop)));
3984 Analyze_And_Resolve (N, Rtyp);
3988 -- If upper bound check succeeds and lower bound check is not
3989 -- known to succeed or fail, then replace the range check with
3990 -- a comparison against the lower bound.
3992 elsif Ucheck in Compare_LE then
3993 if Warn2 and then not In_Instance then
3994 Error_Msg_N ("?upper bound test optimized away", Hi);
3995 Error_Msg_N ("\?value is known to be in range", Hi);
4001 Right_Opnd => Low_Bound (Rop)));
4002 Analyze_And_Resolve (N, Rtyp);
4007 -- We couldn't optimize away the range check, but there is one
4008 -- more issue. If we are checking constant conditionals, then we
4009 -- see if we can determine the outcome assuming everything is
4010 -- valid, and if so give an appropriate warning.
4012 if Warn1 and then not Assume_No_Invalid_Values then
4013 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => True);
4014 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => True);
4016 -- Result is out of range for valid value
4018 if Lcheck = LT or else Ucheck = GT then
4020 ("?value can only be in range if it is invalid", N);
4022 -- Result is in range for valid value
4024 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
4026 ("?value can only be out of range if it is invalid", N);
4028 -- Lower bound check succeeds if value is valid
4030 elsif Warn2 and then Lcheck in Compare_GE then
4032 ("?lower bound check only fails if it is invalid", Lo);
4034 -- Upper bound check succeeds if value is valid
4036 elsif Warn2 and then Ucheck in Compare_LE then
4038 ("?upper bound check only fails for invalid values", Hi);
4043 -- For all other cases of an explicit range, nothing to be done
4047 -- Here right operand is a subtype mark
4051 Typ : Entity_Id := Etype (Rop);
4052 Is_Acc : constant Boolean := Is_Access_Type (Typ);
4053 Obj : Node_Id := Lop;
4054 Cond : Node_Id := Empty;
4057 Remove_Side_Effects (Obj);
4059 -- For tagged type, do tagged membership operation
4061 if Is_Tagged_Type (Typ) then
4063 -- No expansion will be performed when VM_Target, as the VM
4064 -- back-ends will handle the membership tests directly (tags
4065 -- are not explicitly represented in Java objects, so the
4066 -- normal tagged membership expansion is not what we want).
4068 if VM_Target = No_VM then
4069 Rewrite (N, Tagged_Membership (N));
4070 Analyze_And_Resolve (N, Rtyp);
4075 -- If type is scalar type, rewrite as x in t'first .. t'last.
4076 -- This reason we do this is that the bounds may have the wrong
4077 -- type if they come from the original type definition. Also this
4078 -- way we get all the processing above for an explicit range.
4080 elsif Is_Scalar_Type (Typ) then
4084 Make_Attribute_Reference (Loc,
4085 Attribute_Name => Name_First,
4086 Prefix => New_Reference_To (Typ, Loc)),
4089 Make_Attribute_Reference (Loc,
4090 Attribute_Name => Name_Last,
4091 Prefix => New_Reference_To (Typ, Loc))));
4092 Analyze_And_Resolve (N, Rtyp);
4095 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
4096 -- a membership test if the subtype mark denotes a constrained
4097 -- Unchecked_Union subtype and the expression lacks inferable
4100 elsif Is_Unchecked_Union (Base_Type (Typ))
4101 and then Is_Constrained (Typ)
4102 and then not Has_Inferable_Discriminants (Lop)
4105 Make_Raise_Program_Error (Loc,
4106 Reason => PE_Unchecked_Union_Restriction));
4108 -- Prevent Gigi from generating incorrect code by rewriting
4109 -- the test as a standard False.
4112 New_Occurrence_Of (Standard_False, Loc));
4117 -- Here we have a non-scalar type
4120 Typ := Designated_Type (Typ);
4123 if not Is_Constrained (Typ) then
4125 New_Reference_To (Standard_True, Loc));
4126 Analyze_And_Resolve (N, Rtyp);
4128 -- For the constrained array case, we have to check the subscripts
4129 -- for an exact match if the lengths are non-zero (the lengths
4130 -- must match in any case).
4132 elsif Is_Array_Type (Typ) then
4134 Check_Subscripts : declare
4135 function Construct_Attribute_Reference
4138 Dim : Nat) return Node_Id;
4139 -- Build attribute reference E'Nam(Dim)
4141 -----------------------------------
4142 -- Construct_Attribute_Reference --
4143 -----------------------------------
4145 function Construct_Attribute_Reference
4148 Dim : Nat) return Node_Id
4152 Make_Attribute_Reference (Loc,
4154 Attribute_Name => Nam,
4155 Expressions => New_List (
4156 Make_Integer_Literal (Loc, Dim)));
4157 end Construct_Attribute_Reference;
4159 -- Start processing for Check_Subscripts
4162 for J in 1 .. Number_Dimensions (Typ) loop
4163 Evolve_And_Then (Cond,
4166 Construct_Attribute_Reference
4167 (Duplicate_Subexpr_No_Checks (Obj),
4170 Construct_Attribute_Reference
4171 (New_Occurrence_Of (Typ, Loc), Name_First, J)));
4173 Evolve_And_Then (Cond,
4176 Construct_Attribute_Reference
4177 (Duplicate_Subexpr_No_Checks (Obj),
4180 Construct_Attribute_Reference
4181 (New_Occurrence_Of (Typ, Loc), Name_Last, J)));
4190 Right_Opnd => Make_Null (Loc)),
4191 Right_Opnd => Cond);
4195 Analyze_And_Resolve (N, Rtyp);
4196 end Check_Subscripts;
4198 -- These are the cases where constraint checks may be required,
4199 -- e.g. records with possible discriminants
4202 -- Expand the test into a series of discriminant comparisons.
4203 -- The expression that is built is the negation of the one that
4204 -- is used for checking discriminant constraints.
4206 Obj := Relocate_Node (Left_Opnd (N));
4208 if Has_Discriminants (Typ) then
4209 Cond := Make_Op_Not (Loc,
4210 Right_Opnd => Build_Discriminant_Checks (Obj, Typ));
4213 Cond := Make_Or_Else (Loc,
4217 Right_Opnd => Make_Null (Loc)),
4218 Right_Opnd => Cond);
4222 Cond := New_Occurrence_Of (Standard_True, Loc);
4226 Analyze_And_Resolve (N, Rtyp);
4232 --------------------------------
4233 -- Expand_N_Indexed_Component --
4234 --------------------------------
4236 procedure Expand_N_Indexed_Component (N : Node_Id) is
4237 Loc : constant Source_Ptr := Sloc (N);
4238 Typ : constant Entity_Id := Etype (N);
4239 P : constant Node_Id := Prefix (N);
4240 T : constant Entity_Id := Etype (P);
4243 -- A special optimization, if we have an indexed component that is
4244 -- selecting from a slice, then we can eliminate the slice, since, for
4245 -- example, x (i .. j)(k) is identical to x(k). The only difference is
4246 -- the range check required by the slice. The range check for the slice
4247 -- itself has already been generated. The range check for the
4248 -- subscripting operation is ensured by converting the subject to
4249 -- the subtype of the slice.
4251 -- This optimization not only generates better code, avoiding slice
4252 -- messing especially in the packed case, but more importantly bypasses
4253 -- some problems in handling this peculiar case, for example, the issue
4254 -- of dealing specially with object renamings.
4256 if Nkind (P) = N_Slice then
4258 Make_Indexed_Component (Loc,
4259 Prefix => Prefix (P),
4260 Expressions => New_List (
4262 (Etype (First_Index (Etype (P))),
4263 First (Expressions (N))))));
4264 Analyze_And_Resolve (N, Typ);
4268 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
4269 -- function, then additional actuals must be passed.
4271 if Ada_Version >= Ada_05
4272 and then Is_Build_In_Place_Function_Call (P)
4274 Make_Build_In_Place_Call_In_Anonymous_Context (P);
4277 -- If the prefix is an access type, then we unconditionally rewrite if
4278 -- as an explicit deference. This simplifies processing for several
4279 -- cases, including packed array cases and certain cases in which checks
4280 -- must be generated. We used to try to do this only when it was
4281 -- necessary, but it cleans up the code to do it all the time.
4283 if Is_Access_Type (T) then
4284 Insert_Explicit_Dereference (P);
4285 Analyze_And_Resolve (P, Designated_Type (T));
4288 -- Generate index and validity checks
4290 Generate_Index_Checks (N);
4292 if Validity_Checks_On and then Validity_Check_Subscripts then
4293 Apply_Subscript_Validity_Checks (N);
4296 -- All done for the non-packed case
4298 if not Is_Packed (Etype (Prefix (N))) then
4302 -- For packed arrays that are not bit-packed (i.e. the case of an array
4303 -- with one or more index types with a non-contiguous enumeration type),
4304 -- we can always use the normal packed element get circuit.
4306 if not Is_Bit_Packed_Array (Etype (Prefix (N))) then
4307 Expand_Packed_Element_Reference (N);
4311 -- For a reference to a component of a bit packed array, we have to
4312 -- convert it to a reference to the corresponding Packed_Array_Type.
4313 -- We only want to do this for simple references, and not for:
4315 -- Left side of assignment, or prefix of left side of assignment, or
4316 -- prefix of the prefix, to handle packed arrays of packed arrays,
4317 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
4319 -- Renaming objects in renaming associations
4320 -- This case is handled when a use of the renamed variable occurs
4322 -- Actual parameters for a procedure call
4323 -- This case is handled in Exp_Ch6.Expand_Actuals
4325 -- The second expression in a 'Read attribute reference
4327 -- The prefix of an address or size attribute reference
4329 -- The following circuit detects these exceptions
4332 Child : Node_Id := N;
4333 Parnt : Node_Id := Parent (N);
4337 if Nkind (Parnt) = N_Unchecked_Expression then
4340 elsif Nkind_In (Parnt, N_Object_Renaming_Declaration,
4341 N_Procedure_Call_Statement)
4342 or else (Nkind (Parnt) = N_Parameter_Association
4344 Nkind (Parent (Parnt)) = N_Procedure_Call_Statement)
4348 elsif Nkind (Parnt) = N_Attribute_Reference
4349 and then (Attribute_Name (Parnt) = Name_Address
4351 Attribute_Name (Parnt) = Name_Size)
4352 and then Prefix (Parnt) = Child
4356 elsif Nkind (Parnt) = N_Assignment_Statement
4357 and then Name (Parnt) = Child
4361 -- If the expression is an index of an indexed component, it must
4362 -- be expanded regardless of context.
4364 elsif Nkind (Parnt) = N_Indexed_Component
4365 and then Child /= Prefix (Parnt)
4367 Expand_Packed_Element_Reference (N);
4370 elsif Nkind (Parent (Parnt)) = N_Assignment_Statement
4371 and then Name (Parent (Parnt)) = Parnt
4375 elsif Nkind (Parnt) = N_Attribute_Reference
4376 and then Attribute_Name (Parnt) = Name_Read
4377 and then Next (First (Expressions (Parnt))) = Child
4381 elsif Nkind_In (Parnt, N_Indexed_Component, N_Selected_Component)
4382 and then Prefix (Parnt) = Child
4387 Expand_Packed_Element_Reference (N);
4391 -- Keep looking up tree for unchecked expression, or if we are the
4392 -- prefix of a possible assignment left side.
4395 Parnt := Parent (Child);
4398 end Expand_N_Indexed_Component;
4400 ---------------------
4401 -- Expand_N_Not_In --
4402 ---------------------
4404 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
4405 -- can be done. This avoids needing to duplicate this expansion code.
4407 procedure Expand_N_Not_In (N : Node_Id) is
4408 Loc : constant Source_Ptr := Sloc (N);
4409 Typ : constant Entity_Id := Etype (N);
4410 Cfs : constant Boolean := Comes_From_Source (N);
4417 Left_Opnd => Left_Opnd (N),
4418 Right_Opnd => Right_Opnd (N))));
4420 -- We want this to appear as coming from source if original does (see
4421 -- transformations in Expand_N_In).
4423 Set_Comes_From_Source (N, Cfs);
4424 Set_Comes_From_Source (Right_Opnd (N), Cfs);
4426 -- Now analyze transformed node
4428 Analyze_And_Resolve (N, Typ);
4429 end Expand_N_Not_In;
4435 -- The only replacement required is for the case of a null of type that is
4436 -- an access to protected subprogram. We represent such access values as a
4437 -- record, and so we must replace the occurrence of null by the equivalent
4438 -- record (with a null address and a null pointer in it), so that the
4439 -- backend creates the proper value.
4441 procedure Expand_N_Null (N : Node_Id) is
4442 Loc : constant Source_Ptr := Sloc (N);
4443 Typ : constant Entity_Id := Etype (N);
4447 if Is_Access_Protected_Subprogram_Type (Typ) then
4449 Make_Aggregate (Loc,
4450 Expressions => New_List (
4451 New_Occurrence_Of (RTE (RE_Null_Address), Loc),
4455 Analyze_And_Resolve (N, Equivalent_Type (Typ));
4457 -- For subsequent semantic analysis, the node must retain its type.
4458 -- Gigi in any case replaces this type by the corresponding record
4459 -- type before processing the node.
4465 when RE_Not_Available =>
4469 ---------------------
4470 -- Expand_N_Op_Abs --
4471 ---------------------
4473 procedure Expand_N_Op_Abs (N : Node_Id) is
4474 Loc : constant Source_Ptr := Sloc (N);
4475 Expr : constant Node_Id := Right_Opnd (N);
4478 Unary_Op_Validity_Checks (N);
4480 -- Deal with software overflow checking
4482 if not Backend_Overflow_Checks_On_Target
4483 and then Is_Signed_Integer_Type (Etype (N))
4484 and then Do_Overflow_Check (N)
4486 -- The only case to worry about is when the argument is equal to the
4487 -- largest negative number, so what we do is to insert the check:
4489 -- [constraint_error when Expr = typ'Base'First]
4491 -- with the usual Duplicate_Subexpr use coding for expr
4494 Make_Raise_Constraint_Error (Loc,
4497 Left_Opnd => Duplicate_Subexpr (Expr),
4499 Make_Attribute_Reference (Loc,
4501 New_Occurrence_Of (Base_Type (Etype (Expr)), Loc),
4502 Attribute_Name => Name_First)),
4503 Reason => CE_Overflow_Check_Failed));
4506 -- Vax floating-point types case
4508 if Vax_Float (Etype (N)) then
4509 Expand_Vax_Arith (N);
4511 end Expand_N_Op_Abs;
4513 ---------------------
4514 -- Expand_N_Op_Add --
4515 ---------------------
4517 procedure Expand_N_Op_Add (N : Node_Id) is
4518 Typ : constant Entity_Id := Etype (N);
4521 Binary_Op_Validity_Checks (N);
4523 -- N + 0 = 0 + N = N for integer types
4525 if Is_Integer_Type (Typ) then
4526 if Compile_Time_Known_Value (Right_Opnd (N))
4527 and then Expr_Value (Right_Opnd (N)) = Uint_0
4529 Rewrite (N, Left_Opnd (N));
4532 elsif Compile_Time_Known_Value (Left_Opnd (N))
4533 and then Expr_Value (Left_Opnd (N)) = Uint_0
4535 Rewrite (N, Right_Opnd (N));
4540 -- Arithmetic overflow checks for signed integer/fixed point types
4542 if Is_Signed_Integer_Type (Typ)
4543 or else Is_Fixed_Point_Type (Typ)
4545 Apply_Arithmetic_Overflow_Check (N);
4548 -- Vax floating-point types case
4550 elsif Vax_Float (Typ) then
4551 Expand_Vax_Arith (N);
4553 end Expand_N_Op_Add;
4555 ---------------------
4556 -- Expand_N_Op_And --
4557 ---------------------
4559 procedure Expand_N_Op_And (N : Node_Id) is
4560 Typ : constant Entity_Id := Etype (N);
4563 Binary_Op_Validity_Checks (N);
4565 if Is_Array_Type (Etype (N)) then
4566 Expand_Boolean_Operator (N);
4568 elsif Is_Boolean_Type (Etype (N)) then
4569 Adjust_Condition (Left_Opnd (N));
4570 Adjust_Condition (Right_Opnd (N));
4571 Set_Etype (N, Standard_Boolean);
4572 Adjust_Result_Type (N, Typ);
4574 end Expand_N_Op_And;
4576 ------------------------
4577 -- Expand_N_Op_Concat --
4578 ------------------------
4580 procedure Expand_N_Op_Concat (N : Node_Id) is
4582 -- List of operands to be concatenated
4585 -- Node which is to be replaced by the result of concatenating the nodes
4586 -- in the list Opnds.
4589 -- Ensure validity of both operands
4591 Binary_Op_Validity_Checks (N);
4593 -- If we are the left operand of a concatenation higher up the tree,
4594 -- then do nothing for now, since we want to deal with a series of
4595 -- concatenations as a unit.
4597 if Nkind (Parent (N)) = N_Op_Concat
4598 and then N = Left_Opnd (Parent (N))
4603 -- We get here with a concatenation whose left operand may be a
4604 -- concatenation itself with a consistent type. We need to process
4605 -- these concatenation operands from left to right, which means
4606 -- from the deepest node in the tree to the highest node.
4609 while Nkind (Left_Opnd (Cnode)) = N_Op_Concat loop
4610 Cnode := Left_Opnd (Cnode);
4613 -- Now Opnd is the deepest Opnd, and its parents are the concatenation
4614 -- nodes above, so now we process bottom up, doing the operations. We
4615 -- gather a string that is as long as possible up to five operands
4617 -- The outer loop runs more than once if more than one concatenation
4618 -- type is involved.
4621 Opnds := New_List (Left_Opnd (Cnode), Right_Opnd (Cnode));
4622 Set_Parent (Opnds, N);
4624 -- The inner loop gathers concatenation operands
4626 Inner : while Cnode /= N
4627 and then Base_Type (Etype (Cnode)) =
4628 Base_Type (Etype (Parent (Cnode)))
4630 Cnode := Parent (Cnode);
4631 Append (Right_Opnd (Cnode), Opnds);
4634 Expand_Concatenate (Cnode, Opnds);
4636 exit Outer when Cnode = N;
4637 Cnode := Parent (Cnode);
4639 end Expand_N_Op_Concat;
4641 ------------------------
4642 -- Expand_N_Op_Divide --
4643 ------------------------
4645 procedure Expand_N_Op_Divide (N : Node_Id) is
4646 Loc : constant Source_Ptr := Sloc (N);
4647 Lopnd : constant Node_Id := Left_Opnd (N);
4648 Ropnd : constant Node_Id := Right_Opnd (N);
4649 Ltyp : constant Entity_Id := Etype (Lopnd);
4650 Rtyp : constant Entity_Id := Etype (Ropnd);
4651 Typ : Entity_Id := Etype (N);
4652 Rknow : constant Boolean := Is_Integer_Type (Typ)
4654 Compile_Time_Known_Value (Ropnd);
4658 Binary_Op_Validity_Checks (N);
4661 Rval := Expr_Value (Ropnd);
4664 -- N / 1 = N for integer types
4666 if Rknow and then Rval = Uint_1 then
4671 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
4672 -- Is_Power_Of_2_For_Shift is set means that we know that our left
4673 -- operand is an unsigned integer, as required for this to work.
4675 if Nkind (Ropnd) = N_Op_Expon
4676 and then Is_Power_Of_2_For_Shift (Ropnd)
4678 -- We cannot do this transformation in configurable run time mode if we
4679 -- have 64-bit -- integers and long shifts are not available.
4683 or else Support_Long_Shifts_On_Target)
4686 Make_Op_Shift_Right (Loc,
4689 Convert_To (Standard_Natural, Right_Opnd (Ropnd))));
4690 Analyze_And_Resolve (N, Typ);
4694 -- Do required fixup of universal fixed operation
4696 if Typ = Universal_Fixed then
4697 Fixup_Universal_Fixed_Operation (N);
4701 -- Divisions with fixed-point results
4703 if Is_Fixed_Point_Type (Typ) then
4705 -- No special processing if Treat_Fixed_As_Integer is set, since
4706 -- from a semantic point of view such operations are simply integer
4707 -- operations and will be treated that way.
4709 if not Treat_Fixed_As_Integer (N) then
4710 if Is_Integer_Type (Rtyp) then
4711 Expand_Divide_Fixed_By_Integer_Giving_Fixed (N);
4713 Expand_Divide_Fixed_By_Fixed_Giving_Fixed (N);
4717 -- Other cases of division of fixed-point operands. Again we exclude the
4718 -- case where Treat_Fixed_As_Integer is set.
4720 elsif (Is_Fixed_Point_Type (Ltyp) or else
4721 Is_Fixed_Point_Type (Rtyp))
4722 and then not Treat_Fixed_As_Integer (N)
4724 if Is_Integer_Type (Typ) then
4725 Expand_Divide_Fixed_By_Fixed_Giving_Integer (N);
4727 pragma Assert (Is_Floating_Point_Type (Typ));
4728 Expand_Divide_Fixed_By_Fixed_Giving_Float (N);
4731 -- Mixed-mode operations can appear in a non-static universal context,
4732 -- in which case the integer argument must be converted explicitly.
4734 elsif Typ = Universal_Real
4735 and then Is_Integer_Type (Rtyp)
4738 Convert_To (Universal_Real, Relocate_Node (Ropnd)));
4740 Analyze_And_Resolve (Ropnd, Universal_Real);
4742 elsif Typ = Universal_Real
4743 and then Is_Integer_Type (Ltyp)
4746 Convert_To (Universal_Real, Relocate_Node (Lopnd)));
4748 Analyze_And_Resolve (Lopnd, Universal_Real);
4750 -- Non-fixed point cases, do integer zero divide and overflow checks
4752 elsif Is_Integer_Type (Typ) then
4753 Apply_Divide_Check (N);
4755 -- Check for 64-bit division available, or long shifts if the divisor
4756 -- is a small power of 2 (since such divides will be converted into
4759 if Esize (Ltyp) > 32
4760 and then not Support_64_Bit_Divides_On_Target
4763 or else not Support_Long_Shifts_On_Target
4764 or else (Rval /= Uint_2 and then
4765 Rval /= Uint_4 and then
4766 Rval /= Uint_8 and then
4767 Rval /= Uint_16 and then
4768 Rval /= Uint_32 and then
4771 Error_Msg_CRT ("64-bit division", N);
4774 -- Deal with Vax_Float
4776 elsif Vax_Float (Typ) then
4777 Expand_Vax_Arith (N);
4780 end Expand_N_Op_Divide;
4782 --------------------
4783 -- Expand_N_Op_Eq --
4784 --------------------
4786 procedure Expand_N_Op_Eq (N : Node_Id) is
4787 Loc : constant Source_Ptr := Sloc (N);
4788 Typ : constant Entity_Id := Etype (N);
4789 Lhs : constant Node_Id := Left_Opnd (N);
4790 Rhs : constant Node_Id := Right_Opnd (N);
4791 Bodies : constant List_Id := New_List;
4792 A_Typ : constant Entity_Id := Etype (Lhs);
4794 Typl : Entity_Id := A_Typ;
4795 Op_Name : Entity_Id;
4798 procedure Build_Equality_Call (Eq : Entity_Id);
4799 -- If a constructed equality exists for the type or for its parent,
4800 -- build and analyze call, adding conversions if the operation is
4803 function Has_Unconstrained_UU_Component (Typ : Node_Id) return Boolean;
4804 -- Determines whether a type has a subcomponent of an unconstrained
4805 -- Unchecked_Union subtype. Typ is a record type.
4807 -------------------------
4808 -- Build_Equality_Call --
4809 -------------------------
4811 procedure Build_Equality_Call (Eq : Entity_Id) is
4812 Op_Type : constant Entity_Id := Etype (First_Formal (Eq));
4813 L_Exp : Node_Id := Relocate_Node (Lhs);
4814 R_Exp : Node_Id := Relocate_Node (Rhs);
4817 if Base_Type (Op_Type) /= Base_Type (A_Typ)
4818 and then not Is_Class_Wide_Type (A_Typ)
4820 L_Exp := OK_Convert_To (Op_Type, L_Exp);
4821 R_Exp := OK_Convert_To (Op_Type, R_Exp);
4824 -- If we have an Unchecked_Union, we need to add the inferred
4825 -- discriminant values as actuals in the function call. At this
4826 -- point, the expansion has determined that both operands have
4827 -- inferable discriminants.
4829 if Is_Unchecked_Union (Op_Type) then
4831 Lhs_Type : constant Node_Id := Etype (L_Exp);
4832 Rhs_Type : constant Node_Id := Etype (R_Exp);
4833 Lhs_Discr_Val : Node_Id;
4834 Rhs_Discr_Val : Node_Id;
4837 -- Per-object constrained selected components require special
4838 -- attention. If the enclosing scope of the component is an
4839 -- Unchecked_Union, we cannot reference its discriminants
4840 -- directly. This is why we use the two extra parameters of
4841 -- the equality function of the enclosing Unchecked_Union.
4843 -- type UU_Type (Discr : Integer := 0) is
4846 -- pragma Unchecked_Union (UU_Type);
4848 -- 1. Unchecked_Union enclosing record:
4850 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
4852 -- Comp : UU_Type (Discr);
4854 -- end Enclosing_UU_Type;
4855 -- pragma Unchecked_Union (Enclosing_UU_Type);
4857 -- Obj1 : Enclosing_UU_Type;
4858 -- Obj2 : Enclosing_UU_Type (1);
4860 -- [. . .] Obj1 = Obj2 [. . .]
4864 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
4866 -- A and B are the formal parameters of the equality function
4867 -- of Enclosing_UU_Type. The function always has two extra
4868 -- formals to capture the inferred discriminant values.
4870 -- 2. Non-Unchecked_Union enclosing record:
4873 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
4876 -- Comp : UU_Type (Discr);
4878 -- end Enclosing_Non_UU_Type;
4880 -- Obj1 : Enclosing_Non_UU_Type;
4881 -- Obj2 : Enclosing_Non_UU_Type (1);
4883 -- ... Obj1 = Obj2 ...
4887 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
4888 -- obj1.discr, obj2.discr)) then
4890 -- In this case we can directly reference the discriminants of
4891 -- the enclosing record.
4895 if Nkind (Lhs) = N_Selected_Component
4896 and then Has_Per_Object_Constraint
4897 (Entity (Selector_Name (Lhs)))
4899 -- Enclosing record is an Unchecked_Union, use formal A
4901 if Is_Unchecked_Union (Scope
4902 (Entity (Selector_Name (Lhs))))
4905 Make_Identifier (Loc,
4908 -- Enclosing record is of a non-Unchecked_Union type, it is
4909 -- possible to reference the discriminant.
4913 Make_Selected_Component (Loc,
4914 Prefix => Prefix (Lhs),
4917 (Get_Discriminant_Value
4918 (First_Discriminant (Lhs_Type),
4920 Stored_Constraint (Lhs_Type))));
4923 -- Comment needed here ???
4926 -- Infer the discriminant value
4930 (Get_Discriminant_Value
4931 (First_Discriminant (Lhs_Type),
4933 Stored_Constraint (Lhs_Type)));
4938 if Nkind (Rhs) = N_Selected_Component
4939 and then Has_Per_Object_Constraint
4940 (Entity (Selector_Name (Rhs)))
4942 if Is_Unchecked_Union
4943 (Scope (Entity (Selector_Name (Rhs))))
4946 Make_Identifier (Loc,
4951 Make_Selected_Component (Loc,
4952 Prefix => Prefix (Rhs),
4954 New_Copy (Get_Discriminant_Value (
4955 First_Discriminant (Rhs_Type),
4957 Stored_Constraint (Rhs_Type))));
4962 New_Copy (Get_Discriminant_Value (
4963 First_Discriminant (Rhs_Type),
4965 Stored_Constraint (Rhs_Type)));
4970 Make_Function_Call (Loc,
4971 Name => New_Reference_To (Eq, Loc),
4972 Parameter_Associations => New_List (
4979 -- Normal case, not an unchecked union
4983 Make_Function_Call (Loc,
4984 Name => New_Reference_To (Eq, Loc),
4985 Parameter_Associations => New_List (L_Exp, R_Exp)));
4988 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
4989 end Build_Equality_Call;
4991 ------------------------------------
4992 -- Has_Unconstrained_UU_Component --
4993 ------------------------------------
4995 function Has_Unconstrained_UU_Component
4996 (Typ : Node_Id) return Boolean
4998 Tdef : constant Node_Id :=
4999 Type_Definition (Declaration_Node (Base_Type (Typ)));
5003 function Component_Is_Unconstrained_UU
5004 (Comp : Node_Id) return Boolean;
5005 -- Determines whether the subtype of the component is an
5006 -- unconstrained Unchecked_Union.
5008 function Variant_Is_Unconstrained_UU
5009 (Variant : Node_Id) return Boolean;
5010 -- Determines whether a component of the variant has an unconstrained
5011 -- Unchecked_Union subtype.
5013 -----------------------------------
5014 -- Component_Is_Unconstrained_UU --
5015 -----------------------------------
5017 function Component_Is_Unconstrained_UU
5018 (Comp : Node_Id) return Boolean
5021 if Nkind (Comp) /= N_Component_Declaration then
5026 Sindic : constant Node_Id :=
5027 Subtype_Indication (Component_Definition (Comp));
5030 -- Unconstrained nominal type. In the case of a constraint
5031 -- present, the node kind would have been N_Subtype_Indication.
5033 if Nkind (Sindic) = N_Identifier then
5034 return Is_Unchecked_Union (Base_Type (Etype (Sindic)));
5039 end Component_Is_Unconstrained_UU;
5041 ---------------------------------
5042 -- Variant_Is_Unconstrained_UU --
5043 ---------------------------------
5045 function Variant_Is_Unconstrained_UU
5046 (Variant : Node_Id) return Boolean
5048 Clist : constant Node_Id := Component_List (Variant);
5051 if Is_Empty_List (Component_Items (Clist)) then
5055 -- We only need to test one component
5058 Comp : Node_Id := First (Component_Items (Clist));
5061 while Present (Comp) loop
5062 if Component_Is_Unconstrained_UU (Comp) then
5070 -- None of the components withing the variant were of
5071 -- unconstrained Unchecked_Union type.
5074 end Variant_Is_Unconstrained_UU;
5076 -- Start of processing for Has_Unconstrained_UU_Component
5079 if Null_Present (Tdef) then
5083 Clist := Component_List (Tdef);
5084 Vpart := Variant_Part (Clist);
5086 -- Inspect available components
5088 if Present (Component_Items (Clist)) then
5090 Comp : Node_Id := First (Component_Items (Clist));
5093 while Present (Comp) loop
5095 -- One component is sufficient
5097 if Component_Is_Unconstrained_UU (Comp) then
5106 -- Inspect available components withing variants
5108 if Present (Vpart) then
5110 Variant : Node_Id := First (Variants (Vpart));
5113 while Present (Variant) loop
5115 -- One component within a variant is sufficient
5117 if Variant_Is_Unconstrained_UU (Variant) then
5126 -- Neither the available components, nor the components inside the
5127 -- variant parts were of an unconstrained Unchecked_Union subtype.
5130 end Has_Unconstrained_UU_Component;
5132 -- Start of processing for Expand_N_Op_Eq
5135 Binary_Op_Validity_Checks (N);
5137 if Ekind (Typl) = E_Private_Type then
5138 Typl := Underlying_Type (Typl);
5139 elsif Ekind (Typl) = E_Private_Subtype then
5140 Typl := Underlying_Type (Base_Type (Typl));
5145 -- It may happen in error situations that the underlying type is not
5146 -- set. The error will be detected later, here we just defend the
5153 Typl := Base_Type (Typl);
5155 -- Boolean types (requiring handling of non-standard case)
5157 if Is_Boolean_Type (Typl) then
5158 Adjust_Condition (Left_Opnd (N));
5159 Adjust_Condition (Right_Opnd (N));
5160 Set_Etype (N, Standard_Boolean);
5161 Adjust_Result_Type (N, Typ);
5165 elsif Is_Array_Type (Typl) then
5167 -- If we are doing full validity checking, and it is possible for the
5168 -- array elements to be invalid then expand out array comparisons to
5169 -- make sure that we check the array elements.
5171 if Validity_Check_Operands
5172 and then not Is_Known_Valid (Component_Type (Typl))
5175 Save_Force_Validity_Checks : constant Boolean :=
5176 Force_Validity_Checks;
5178 Force_Validity_Checks := True;
5180 Expand_Array_Equality
5182 Relocate_Node (Lhs),
5183 Relocate_Node (Rhs),
5186 Insert_Actions (N, Bodies);
5187 Analyze_And_Resolve (N, Standard_Boolean);
5188 Force_Validity_Checks := Save_Force_Validity_Checks;
5191 -- Packed case where both operands are known aligned
5193 elsif Is_Bit_Packed_Array (Typl)
5194 and then not Is_Possibly_Unaligned_Object (Lhs)
5195 and then not Is_Possibly_Unaligned_Object (Rhs)
5197 Expand_Packed_Eq (N);
5199 -- Where the component type is elementary we can use a block bit
5200 -- comparison (if supported on the target) exception in the case
5201 -- of floating-point (negative zero issues require element by
5202 -- element comparison), and atomic types (where we must be sure
5203 -- to load elements independently) and possibly unaligned arrays.
5205 elsif Is_Elementary_Type (Component_Type (Typl))
5206 and then not Is_Floating_Point_Type (Component_Type (Typl))
5207 and then not Is_Atomic (Component_Type (Typl))
5208 and then not Is_Possibly_Unaligned_Object (Lhs)
5209 and then not Is_Possibly_Unaligned_Object (Rhs)
5210 and then Support_Composite_Compare_On_Target
5214 -- For composite and floating-point cases, expand equality loop to
5215 -- make sure of using proper comparisons for tagged types, and
5216 -- correctly handling the floating-point case.
5220 Expand_Array_Equality
5222 Relocate_Node (Lhs),
5223 Relocate_Node (Rhs),
5226 Insert_Actions (N, Bodies, Suppress => All_Checks);
5227 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5232 elsif Is_Record_Type (Typl) then
5234 -- For tagged types, use the primitive "="
5236 if Is_Tagged_Type (Typl) then
5238 -- No need to do anything else compiling under restriction
5239 -- No_Dispatching_Calls. During the semantic analysis we
5240 -- already notified such violation.
5242 if Restriction_Active (No_Dispatching_Calls) then
5246 -- If this is derived from an untagged private type completed with
5247 -- a tagged type, it does not have a full view, so we use the
5248 -- primitive operations of the private type. This check should no
5249 -- longer be necessary when these types get their full views???
5251 if Is_Private_Type (A_Typ)
5252 and then not Is_Tagged_Type (A_Typ)
5253 and then Is_Derived_Type (A_Typ)
5254 and then No (Full_View (A_Typ))
5256 -- Search for equality operation, checking that the operands
5257 -- have the same type. Note that we must find a matching entry,
5258 -- or something is very wrong!
5260 Prim := First_Elmt (Collect_Primitive_Operations (A_Typ));
5262 while Present (Prim) loop
5263 exit when Chars (Node (Prim)) = Name_Op_Eq
5264 and then Etype (First_Formal (Node (Prim))) =
5265 Etype (Next_Formal (First_Formal (Node (Prim))))
5267 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
5272 pragma Assert (Present (Prim));
5273 Op_Name := Node (Prim);
5275 -- Find the type's predefined equality or an overriding
5276 -- user- defined equality. The reason for not simply calling
5277 -- Find_Prim_Op here is that there may be a user-defined
5278 -- overloaded equality op that precedes the equality that we want,
5279 -- so we have to explicitly search (e.g., there could be an
5280 -- equality with two different parameter types).
5283 if Is_Class_Wide_Type (Typl) then
5284 Typl := Root_Type (Typl);
5287 Prim := First_Elmt (Primitive_Operations (Typl));
5288 while Present (Prim) loop
5289 exit when Chars (Node (Prim)) = Name_Op_Eq
5290 and then Etype (First_Formal (Node (Prim))) =
5291 Etype (Next_Formal (First_Formal (Node (Prim))))
5293 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
5298 pragma Assert (Present (Prim));
5299 Op_Name := Node (Prim);
5302 Build_Equality_Call (Op_Name);
5304 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
5305 -- predefined equality operator for a type which has a subcomponent
5306 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
5308 elsif Has_Unconstrained_UU_Component (Typl) then
5310 Make_Raise_Program_Error (Loc,
5311 Reason => PE_Unchecked_Union_Restriction));
5313 -- Prevent Gigi from generating incorrect code by rewriting the
5314 -- equality as a standard False.
5317 New_Occurrence_Of (Standard_False, Loc));
5319 elsif Is_Unchecked_Union (Typl) then
5321 -- If we can infer the discriminants of the operands, we make a
5322 -- call to the TSS equality function.
5324 if Has_Inferable_Discriminants (Lhs)
5326 Has_Inferable_Discriminants (Rhs)
5329 (TSS (Root_Type (Typl), TSS_Composite_Equality));
5332 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
5333 -- the predefined equality operator for an Unchecked_Union type
5334 -- if either of the operands lack inferable discriminants.
5337 Make_Raise_Program_Error (Loc,
5338 Reason => PE_Unchecked_Union_Restriction));
5340 -- Prevent Gigi from generating incorrect code by rewriting
5341 -- the equality as a standard False.
5344 New_Occurrence_Of (Standard_False, Loc));
5348 -- If a type support function is present (for complex cases), use it
5350 elsif Present (TSS (Root_Type (Typl), TSS_Composite_Equality)) then
5352 (TSS (Root_Type (Typl), TSS_Composite_Equality));
5354 -- Otherwise expand the component by component equality. Note that
5355 -- we never use block-bit comparisons for records, because of the
5356 -- problems with gaps. The backend will often be able to recombine
5357 -- the separate comparisons that we generate here.
5360 Remove_Side_Effects (Lhs);
5361 Remove_Side_Effects (Rhs);
5363 Expand_Record_Equality (N, Typl, Lhs, Rhs, Bodies));
5365 Insert_Actions (N, Bodies, Suppress => All_Checks);
5366 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5370 -- Test if result is known at compile time
5372 Rewrite_Comparison (N);
5374 -- If we still have comparison for Vax_Float, process it
5376 if Vax_Float (Typl) and then Nkind (N) in N_Op_Compare then
5377 Expand_Vax_Comparison (N);
5382 -----------------------
5383 -- Expand_N_Op_Expon --
5384 -----------------------
5386 procedure Expand_N_Op_Expon (N : Node_Id) is
5387 Loc : constant Source_Ptr := Sloc (N);
5388 Typ : constant Entity_Id := Etype (N);
5389 Rtyp : constant Entity_Id := Root_Type (Typ);
5390 Base : constant Node_Id := Relocate_Node (Left_Opnd (N));
5391 Bastyp : constant Node_Id := Etype (Base);
5392 Exp : constant Node_Id := Relocate_Node (Right_Opnd (N));
5393 Exptyp : constant Entity_Id := Etype (Exp);
5394 Ovflo : constant Boolean := Do_Overflow_Check (N);
5403 Binary_Op_Validity_Checks (N);
5405 -- If either operand is of a private type, then we have the use of an
5406 -- intrinsic operator, and we get rid of the privateness, by using root
5407 -- types of underlying types for the actual operation. Otherwise the
5408 -- private types will cause trouble if we expand multiplications or
5409 -- shifts etc. We also do this transformation if the result type is
5410 -- different from the base type.
5412 if Is_Private_Type (Etype (Base))
5414 Is_Private_Type (Typ)
5416 Is_Private_Type (Exptyp)
5418 Rtyp /= Root_Type (Bastyp)
5421 Bt : constant Entity_Id := Root_Type (Underlying_Type (Bastyp));
5422 Et : constant Entity_Id := Root_Type (Underlying_Type (Exptyp));
5426 Unchecked_Convert_To (Typ,
5428 Left_Opnd => Unchecked_Convert_To (Bt, Base),
5429 Right_Opnd => Unchecked_Convert_To (Et, Exp))));
5430 Analyze_And_Resolve (N, Typ);
5435 -- Test for case of known right argument
5437 if Compile_Time_Known_Value (Exp) then
5438 Expv := Expr_Value (Exp);
5440 -- We only fold small non-negative exponents. You might think we
5441 -- could fold small negative exponents for the real case, but we
5442 -- can't because we are required to raise Constraint_Error for
5443 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
5444 -- See ACVC test C4A012B.
5446 if Expv >= 0 and then Expv <= 4 then
5448 -- X ** 0 = 1 (or 1.0)
5452 -- Call Remove_Side_Effects to ensure that any side effects
5453 -- in the ignored left operand (in particular function calls
5454 -- to user defined functions) are properly executed.
5456 Remove_Side_Effects (Base);
5458 if Ekind (Typ) in Integer_Kind then
5459 Xnode := Make_Integer_Literal (Loc, Intval => 1);
5461 Xnode := Make_Real_Literal (Loc, Ureal_1);
5473 Make_Op_Multiply (Loc,
5474 Left_Opnd => Duplicate_Subexpr (Base),
5475 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
5477 -- X ** 3 = X * X * X
5481 Make_Op_Multiply (Loc,
5483 Make_Op_Multiply (Loc,
5484 Left_Opnd => Duplicate_Subexpr (Base),
5485 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)),
5486 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
5489 -- En : constant base'type := base * base;
5495 Make_Defining_Identifier (Loc, New_Internal_Name ('E'));
5497 Insert_Actions (N, New_List (
5498 Make_Object_Declaration (Loc,
5499 Defining_Identifier => Temp,
5500 Constant_Present => True,
5501 Object_Definition => New_Reference_To (Typ, Loc),
5503 Make_Op_Multiply (Loc,
5504 Left_Opnd => Duplicate_Subexpr (Base),
5505 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)))));
5508 Make_Op_Multiply (Loc,
5509 Left_Opnd => New_Reference_To (Temp, Loc),
5510 Right_Opnd => New_Reference_To (Temp, Loc));
5514 Analyze_And_Resolve (N, Typ);
5519 -- Case of (2 ** expression) appearing as an argument of an integer
5520 -- multiplication, or as the right argument of a division of a non-
5521 -- negative integer. In such cases we leave the node untouched, setting
5522 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
5523 -- of the higher level node converts it into a shift.
5525 -- Note: this transformation is not applicable for a modular type with
5526 -- a non-binary modulus in the multiplication case, since we get a wrong
5527 -- result if the shift causes an overflow before the modular reduction.
5529 if Nkind (Base) = N_Integer_Literal
5530 and then Intval (Base) = 2
5531 and then Is_Integer_Type (Root_Type (Exptyp))
5532 and then Esize (Root_Type (Exptyp)) <= Esize (Standard_Integer)
5533 and then Is_Unsigned_Type (Exptyp)
5535 and then Nkind (Parent (N)) in N_Binary_Op
5538 P : constant Node_Id := Parent (N);
5539 L : constant Node_Id := Left_Opnd (P);
5540 R : constant Node_Id := Right_Opnd (P);
5543 if (Nkind (P) = N_Op_Multiply
5544 and then not Non_Binary_Modulus (Typ)
5546 ((Is_Integer_Type (Etype (L)) and then R = N)
5548 (Is_Integer_Type (Etype (R)) and then L = N))
5549 and then not Do_Overflow_Check (P))
5552 (Nkind (P) = N_Op_Divide
5553 and then Is_Integer_Type (Etype (L))
5554 and then Is_Unsigned_Type (Etype (L))
5556 and then not Do_Overflow_Check (P))
5558 Set_Is_Power_Of_2_For_Shift (N);
5564 -- Fall through if exponentiation must be done using a runtime routine
5566 -- First deal with modular case
5568 if Is_Modular_Integer_Type (Rtyp) then
5570 -- Non-binary case, we call the special exponentiation routine for
5571 -- the non-binary case, converting the argument to Long_Long_Integer
5572 -- and passing the modulus value. Then the result is converted back
5573 -- to the base type.
5575 if Non_Binary_Modulus (Rtyp) then
5578 Make_Function_Call (Loc,
5579 Name => New_Reference_To (RTE (RE_Exp_Modular), Loc),
5580 Parameter_Associations => New_List (
5581 Convert_To (Standard_Integer, Base),
5582 Make_Integer_Literal (Loc, Modulus (Rtyp)),
5585 -- Binary case, in this case, we call one of two routines, either the
5586 -- unsigned integer case, or the unsigned long long integer case,
5587 -- with a final "and" operation to do the required mod.
5590 if UI_To_Int (Esize (Rtyp)) <= Standard_Integer_Size then
5591 Ent := RTE (RE_Exp_Unsigned);
5593 Ent := RTE (RE_Exp_Long_Long_Unsigned);
5600 Make_Function_Call (Loc,
5601 Name => New_Reference_To (Ent, Loc),
5602 Parameter_Associations => New_List (
5603 Convert_To (Etype (First_Formal (Ent)), Base),
5606 Make_Integer_Literal (Loc, Modulus (Rtyp) - 1))));
5610 -- Common exit point for modular type case
5612 Analyze_And_Resolve (N, Typ);
5615 -- Signed integer cases, done using either Integer or Long_Long_Integer.
5616 -- It is not worth having routines for Short_[Short_]Integer, since for
5617 -- most machines it would not help, and it would generate more code that
5618 -- might need certification when a certified run time is required.
5620 -- In the integer cases, we have two routines, one for when overflow
5621 -- checks are required, and one when they are not required, since there
5622 -- is a real gain in omitting checks on many machines.
5624 elsif Rtyp = Base_Type (Standard_Long_Long_Integer)
5625 or else (Rtyp = Base_Type (Standard_Long_Integer)
5627 Esize (Standard_Long_Integer) > Esize (Standard_Integer))
5628 or else (Rtyp = Universal_Integer)
5630 Etyp := Standard_Long_Long_Integer;
5633 Rent := RE_Exp_Long_Long_Integer;
5635 Rent := RE_Exn_Long_Long_Integer;
5638 elsif Is_Signed_Integer_Type (Rtyp) then
5639 Etyp := Standard_Integer;
5642 Rent := RE_Exp_Integer;
5644 Rent := RE_Exn_Integer;
5647 -- Floating-point cases, always done using Long_Long_Float. We do not
5648 -- need separate routines for the overflow case here, since in the case
5649 -- of floating-point, we generate infinities anyway as a rule (either
5650 -- that or we automatically trap overflow), and if there is an infinity
5651 -- generated and a range check is required, the check will fail anyway.
5654 pragma Assert (Is_Floating_Point_Type (Rtyp));
5655 Etyp := Standard_Long_Long_Float;
5656 Rent := RE_Exn_Long_Long_Float;
5659 -- Common processing for integer cases and floating-point cases.
5660 -- If we are in the right type, we can call runtime routine directly
5663 and then Rtyp /= Universal_Integer
5664 and then Rtyp /= Universal_Real
5667 Make_Function_Call (Loc,
5668 Name => New_Reference_To (RTE (Rent), Loc),
5669 Parameter_Associations => New_List (Base, Exp)));
5671 -- Otherwise we have to introduce conversions (conversions are also
5672 -- required in the universal cases, since the runtime routine is
5673 -- typed using one of the standard types.
5678 Make_Function_Call (Loc,
5679 Name => New_Reference_To (RTE (Rent), Loc),
5680 Parameter_Associations => New_List (
5681 Convert_To (Etyp, Base),
5685 Analyze_And_Resolve (N, Typ);
5689 when RE_Not_Available =>
5691 end Expand_N_Op_Expon;
5693 --------------------
5694 -- Expand_N_Op_Ge --
5695 --------------------
5697 procedure Expand_N_Op_Ge (N : Node_Id) is
5698 Typ : constant Entity_Id := Etype (N);
5699 Op1 : constant Node_Id := Left_Opnd (N);
5700 Op2 : constant Node_Id := Right_Opnd (N);
5701 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5704 Binary_Op_Validity_Checks (N);
5706 if Is_Array_Type (Typ1) then
5707 Expand_Array_Comparison (N);
5711 if Is_Boolean_Type (Typ1) then
5712 Adjust_Condition (Op1);
5713 Adjust_Condition (Op2);
5714 Set_Etype (N, Standard_Boolean);
5715 Adjust_Result_Type (N, Typ);
5718 Rewrite_Comparison (N);
5720 -- If we still have comparison, and Vax_Float type, process it
5722 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5723 Expand_Vax_Comparison (N);
5728 --------------------
5729 -- Expand_N_Op_Gt --
5730 --------------------
5732 procedure Expand_N_Op_Gt (N : Node_Id) is
5733 Typ : constant Entity_Id := Etype (N);
5734 Op1 : constant Node_Id := Left_Opnd (N);
5735 Op2 : constant Node_Id := Right_Opnd (N);
5736 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5739 Binary_Op_Validity_Checks (N);
5741 if Is_Array_Type (Typ1) then
5742 Expand_Array_Comparison (N);
5746 if Is_Boolean_Type (Typ1) then
5747 Adjust_Condition (Op1);
5748 Adjust_Condition (Op2);
5749 Set_Etype (N, Standard_Boolean);
5750 Adjust_Result_Type (N, Typ);
5753 Rewrite_Comparison (N);
5755 -- If we still have comparison, and Vax_Float type, process it
5757 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5758 Expand_Vax_Comparison (N);
5763 --------------------
5764 -- Expand_N_Op_Le --
5765 --------------------
5767 procedure Expand_N_Op_Le (N : Node_Id) is
5768 Typ : constant Entity_Id := Etype (N);
5769 Op1 : constant Node_Id := Left_Opnd (N);
5770 Op2 : constant Node_Id := Right_Opnd (N);
5771 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5774 Binary_Op_Validity_Checks (N);
5776 if Is_Array_Type (Typ1) then
5777 Expand_Array_Comparison (N);
5781 if Is_Boolean_Type (Typ1) then
5782 Adjust_Condition (Op1);
5783 Adjust_Condition (Op2);
5784 Set_Etype (N, Standard_Boolean);
5785 Adjust_Result_Type (N, Typ);
5788 Rewrite_Comparison (N);
5790 -- If we still have comparison, and Vax_Float type, process it
5792 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5793 Expand_Vax_Comparison (N);
5798 --------------------
5799 -- Expand_N_Op_Lt --
5800 --------------------
5802 procedure Expand_N_Op_Lt (N : Node_Id) is
5803 Typ : constant Entity_Id := Etype (N);
5804 Op1 : constant Node_Id := Left_Opnd (N);
5805 Op2 : constant Node_Id := Right_Opnd (N);
5806 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
5809 Binary_Op_Validity_Checks (N);
5811 if Is_Array_Type (Typ1) then
5812 Expand_Array_Comparison (N);
5816 if Is_Boolean_Type (Typ1) then
5817 Adjust_Condition (Op1);
5818 Adjust_Condition (Op2);
5819 Set_Etype (N, Standard_Boolean);
5820 Adjust_Result_Type (N, Typ);
5823 Rewrite_Comparison (N);
5825 -- If we still have comparison, and Vax_Float type, process it
5827 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
5828 Expand_Vax_Comparison (N);
5833 -----------------------
5834 -- Expand_N_Op_Minus --
5835 -----------------------
5837 procedure Expand_N_Op_Minus (N : Node_Id) is
5838 Loc : constant Source_Ptr := Sloc (N);
5839 Typ : constant Entity_Id := Etype (N);
5842 Unary_Op_Validity_Checks (N);
5844 if not Backend_Overflow_Checks_On_Target
5845 and then Is_Signed_Integer_Type (Etype (N))
5846 and then Do_Overflow_Check (N)
5848 -- Software overflow checking expands -expr into (0 - expr)
5851 Make_Op_Subtract (Loc,
5852 Left_Opnd => Make_Integer_Literal (Loc, 0),
5853 Right_Opnd => Right_Opnd (N)));
5855 Analyze_And_Resolve (N, Typ);
5857 -- Vax floating-point types case
5859 elsif Vax_Float (Etype (N)) then
5860 Expand_Vax_Arith (N);
5862 end Expand_N_Op_Minus;
5864 ---------------------
5865 -- Expand_N_Op_Mod --
5866 ---------------------
5868 procedure Expand_N_Op_Mod (N : Node_Id) is
5869 Loc : constant Source_Ptr := Sloc (N);
5870 Typ : constant Entity_Id := Etype (N);
5871 Left : constant Node_Id := Left_Opnd (N);
5872 Right : constant Node_Id := Right_Opnd (N);
5873 DOC : constant Boolean := Do_Overflow_Check (N);
5874 DDC : constant Boolean := Do_Division_Check (N);
5884 pragma Warnings (Off, Lhi);
5887 Binary_Op_Validity_Checks (N);
5889 Determine_Range (Right, ROK, Rlo, Rhi);
5890 Determine_Range (Left, LOK, Llo, Lhi);
5892 -- Convert mod to rem if operands are known non-negative. We do this
5893 -- since it is quite likely that this will improve the quality of code,
5894 -- (the operation now corresponds to the hardware remainder), and it
5895 -- does not seem likely that it could be harmful.
5897 if LOK and then Llo >= 0
5899 ROK and then Rlo >= 0
5902 Make_Op_Rem (Sloc (N),
5903 Left_Opnd => Left_Opnd (N),
5904 Right_Opnd => Right_Opnd (N)));
5906 -- Instead of reanalyzing the node we do the analysis manually. This
5907 -- avoids anomalies when the replacement is done in an instance and
5908 -- is epsilon more efficient.
5910 Set_Entity (N, Standard_Entity (S_Op_Rem));
5912 Set_Do_Overflow_Check (N, DOC);
5913 Set_Do_Division_Check (N, DDC);
5914 Expand_N_Op_Rem (N);
5917 -- Otherwise, normal mod processing
5920 if Is_Integer_Type (Etype (N)) then
5921 Apply_Divide_Check (N);
5924 -- Apply optimization x mod 1 = 0. We don't really need that with
5925 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
5926 -- certainly harmless.
5928 if Is_Integer_Type (Etype (N))
5929 and then Compile_Time_Known_Value (Right)
5930 and then Expr_Value (Right) = Uint_1
5932 -- Call Remove_Side_Effects to ensure that any side effects in
5933 -- the ignored left operand (in particular function calls to
5934 -- user defined functions) are properly executed.
5936 Remove_Side_Effects (Left);
5938 Rewrite (N, Make_Integer_Literal (Loc, 0));
5939 Analyze_And_Resolve (N, Typ);
5943 -- Deal with annoying case of largest negative number remainder
5944 -- minus one. Gigi does not handle this case correctly, because
5945 -- it generates a divide instruction which may trap in this case.
5947 -- In fact the check is quite easy, if the right operand is -1, then
5948 -- the mod value is always 0, and we can just ignore the left operand
5949 -- completely in this case.
5951 -- The operand type may be private (e.g. in the expansion of an
5952 -- intrinsic operation) so we must use the underlying type to get the
5953 -- bounds, and convert the literals explicitly.
5957 (Type_Low_Bound (Base_Type (Underlying_Type (Etype (Left)))));
5959 if ((not ROK) or else (Rlo <= (-1) and then (-1) <= Rhi))
5961 ((not LOK) or else (Llo = LLB))
5964 Make_Conditional_Expression (Loc,
5965 Expressions => New_List (
5967 Left_Opnd => Duplicate_Subexpr (Right),
5969 Unchecked_Convert_To (Typ,
5970 Make_Integer_Literal (Loc, -1))),
5971 Unchecked_Convert_To (Typ,
5972 Make_Integer_Literal (Loc, Uint_0)),
5973 Relocate_Node (N))));
5975 Set_Analyzed (Next (Next (First (Expressions (N)))));
5976 Analyze_And_Resolve (N, Typ);
5979 end Expand_N_Op_Mod;
5981 --------------------------
5982 -- Expand_N_Op_Multiply --
5983 --------------------------
5985 procedure Expand_N_Op_Multiply (N : Node_Id) is
5986 Loc : constant Source_Ptr := Sloc (N);
5987 Lop : constant Node_Id := Left_Opnd (N);
5988 Rop : constant Node_Id := Right_Opnd (N);
5990 Lp2 : constant Boolean :=
5991 Nkind (Lop) = N_Op_Expon
5992 and then Is_Power_Of_2_For_Shift (Lop);
5994 Rp2 : constant Boolean :=
5995 Nkind (Rop) = N_Op_Expon
5996 and then Is_Power_Of_2_For_Shift (Rop);
5998 Ltyp : constant Entity_Id := Etype (Lop);
5999 Rtyp : constant Entity_Id := Etype (Rop);
6000 Typ : Entity_Id := Etype (N);
6003 Binary_Op_Validity_Checks (N);
6005 -- Special optimizations for integer types
6007 if Is_Integer_Type (Typ) then
6009 -- N * 0 = 0 for integer types
6011 if Compile_Time_Known_Value (Rop)
6012 and then Expr_Value (Rop) = Uint_0
6014 -- Call Remove_Side_Effects to ensure that any side effects in
6015 -- the ignored left operand (in particular function calls to
6016 -- user defined functions) are properly executed.
6018 Remove_Side_Effects (Lop);
6020 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
6021 Analyze_And_Resolve (N, Typ);
6025 -- Similar handling for 0 * N = 0
6027 if Compile_Time_Known_Value (Lop)
6028 and then Expr_Value (Lop) = Uint_0
6030 Remove_Side_Effects (Rop);
6031 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
6032 Analyze_And_Resolve (N, Typ);
6036 -- N * 1 = 1 * N = N for integer types
6038 -- This optimisation is not done if we are going to
6039 -- rewrite the product 1 * 2 ** N to a shift.
6041 if Compile_Time_Known_Value (Rop)
6042 and then Expr_Value (Rop) = Uint_1
6048 elsif Compile_Time_Known_Value (Lop)
6049 and then Expr_Value (Lop) = Uint_1
6057 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
6058 -- Is_Power_Of_2_For_Shift is set means that we know that our left
6059 -- operand is an integer, as required for this to work.
6064 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
6068 Left_Opnd => Make_Integer_Literal (Loc, 2),
6071 Left_Opnd => Right_Opnd (Lop),
6072 Right_Opnd => Right_Opnd (Rop))));
6073 Analyze_And_Resolve (N, Typ);
6078 Make_Op_Shift_Left (Loc,
6081 Convert_To (Standard_Natural, Right_Opnd (Rop))));
6082 Analyze_And_Resolve (N, Typ);
6086 -- Same processing for the operands the other way round
6090 Make_Op_Shift_Left (Loc,
6093 Convert_To (Standard_Natural, Right_Opnd (Lop))));
6094 Analyze_And_Resolve (N, Typ);
6098 -- Do required fixup of universal fixed operation
6100 if Typ = Universal_Fixed then
6101 Fixup_Universal_Fixed_Operation (N);
6105 -- Multiplications with fixed-point results
6107 if Is_Fixed_Point_Type (Typ) then
6109 -- No special processing if Treat_Fixed_As_Integer is set, since from
6110 -- a semantic point of view such operations are simply integer
6111 -- operations and will be treated that way.
6113 if not Treat_Fixed_As_Integer (N) then
6115 -- Case of fixed * integer => fixed
6117 if Is_Integer_Type (Rtyp) then
6118 Expand_Multiply_Fixed_By_Integer_Giving_Fixed (N);
6120 -- Case of integer * fixed => fixed
6122 elsif Is_Integer_Type (Ltyp) then
6123 Expand_Multiply_Integer_By_Fixed_Giving_Fixed (N);
6125 -- Case of fixed * fixed => fixed
6128 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed (N);
6132 -- Other cases of multiplication of fixed-point operands. Again we
6133 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
6135 elsif (Is_Fixed_Point_Type (Ltyp) or else Is_Fixed_Point_Type (Rtyp))
6136 and then not Treat_Fixed_As_Integer (N)
6138 if Is_Integer_Type (Typ) then
6139 Expand_Multiply_Fixed_By_Fixed_Giving_Integer (N);
6141 pragma Assert (Is_Floating_Point_Type (Typ));
6142 Expand_Multiply_Fixed_By_Fixed_Giving_Float (N);
6145 -- Mixed-mode operations can appear in a non-static universal context,
6146 -- in which case the integer argument must be converted explicitly.
6148 elsif Typ = Universal_Real
6149 and then Is_Integer_Type (Rtyp)
6151 Rewrite (Rop, Convert_To (Universal_Real, Relocate_Node (Rop)));
6153 Analyze_And_Resolve (Rop, Universal_Real);
6155 elsif Typ = Universal_Real
6156 and then Is_Integer_Type (Ltyp)
6158 Rewrite (Lop, Convert_To (Universal_Real, Relocate_Node (Lop)));
6160 Analyze_And_Resolve (Lop, Universal_Real);
6162 -- Non-fixed point cases, check software overflow checking required
6164 elsif Is_Signed_Integer_Type (Etype (N)) then
6165 Apply_Arithmetic_Overflow_Check (N);
6167 -- Deal with VAX float case
6169 elsif Vax_Float (Typ) then
6170 Expand_Vax_Arith (N);
6173 end Expand_N_Op_Multiply;
6175 --------------------
6176 -- Expand_N_Op_Ne --
6177 --------------------
6179 procedure Expand_N_Op_Ne (N : Node_Id) is
6180 Typ : constant Entity_Id := Etype (Left_Opnd (N));
6183 -- Case of elementary type with standard operator
6185 if Is_Elementary_Type (Typ)
6186 and then Sloc (Entity (N)) = Standard_Location
6188 Binary_Op_Validity_Checks (N);
6190 -- Boolean types (requiring handling of non-standard case)
6192 if Is_Boolean_Type (Typ) then
6193 Adjust_Condition (Left_Opnd (N));
6194 Adjust_Condition (Right_Opnd (N));
6195 Set_Etype (N, Standard_Boolean);
6196 Adjust_Result_Type (N, Typ);
6199 Rewrite_Comparison (N);
6201 -- If we still have comparison for Vax_Float, process it
6203 if Vax_Float (Typ) and then Nkind (N) in N_Op_Compare then
6204 Expand_Vax_Comparison (N);
6208 -- For all cases other than elementary types, we rewrite node as the
6209 -- negation of an equality operation, and reanalyze. The equality to be
6210 -- used is defined in the same scope and has the same signature. This
6211 -- signature must be set explicitly since in an instance it may not have
6212 -- the same visibility as in the generic unit. This avoids duplicating
6213 -- or factoring the complex code for record/array equality tests etc.
6217 Loc : constant Source_Ptr := Sloc (N);
6219 Ne : constant Entity_Id := Entity (N);
6222 Binary_Op_Validity_Checks (N);
6228 Left_Opnd => Left_Opnd (N),
6229 Right_Opnd => Right_Opnd (N)));
6230 Set_Paren_Count (Right_Opnd (Neg), 1);
6232 if Scope (Ne) /= Standard_Standard then
6233 Set_Entity (Right_Opnd (Neg), Corresponding_Equality (Ne));
6236 -- For navigation purposes, the inequality is treated as an
6237 -- implicit reference to the corresponding equality. Preserve the
6238 -- Comes_From_ source flag so that the proper Xref entry is
6241 Preserve_Comes_From_Source (Neg, N);
6242 Preserve_Comes_From_Source (Right_Opnd (Neg), N);
6244 Analyze_And_Resolve (N, Standard_Boolean);
6249 ---------------------
6250 -- Expand_N_Op_Not --
6251 ---------------------
6253 -- If the argument is other than a Boolean array type, there is no special
6254 -- expansion required.
6256 -- For the packed case, we call the special routine in Exp_Pakd, except
6257 -- that if the component size is greater than one, we use the standard
6258 -- routine generating a gruesome loop (it is so peculiar to have packed
6259 -- arrays with non-standard Boolean representations anyway, so it does not
6260 -- matter that we do not handle this case efficiently).
6262 -- For the unpacked case (and for the special packed case where we have non
6263 -- standard Booleans, as discussed above), we generate and insert into the
6264 -- tree the following function definition:
6266 -- function Nnnn (A : arr) is
6269 -- for J in a'range loop
6270 -- B (J) := not A (J);
6275 -- Here arr is the actual subtype of the parameter (and hence always
6276 -- constrained). Then we replace the not with a call to this function.
6278 procedure Expand_N_Op_Not (N : Node_Id) is
6279 Loc : constant Source_Ptr := Sloc (N);
6280 Typ : constant Entity_Id := Etype (N);
6289 Func_Name : Entity_Id;
6290 Loop_Statement : Node_Id;
6293 Unary_Op_Validity_Checks (N);
6295 -- For boolean operand, deal with non-standard booleans
6297 if Is_Boolean_Type (Typ) then
6298 Adjust_Condition (Right_Opnd (N));
6299 Set_Etype (N, Standard_Boolean);
6300 Adjust_Result_Type (N, Typ);
6304 -- Only array types need any other processing
6306 if not Is_Array_Type (Typ) then
6310 -- Case of array operand. If bit packed with a component size of 1,
6311 -- handle it in Exp_Pakd if the operand is known to be aligned.
6313 if Is_Bit_Packed_Array (Typ)
6314 and then Component_Size (Typ) = 1
6315 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
6317 Expand_Packed_Not (N);
6321 -- Case of array operand which is not bit-packed. If the context is
6322 -- a safe assignment, call in-place operation, If context is a larger
6323 -- boolean expression in the context of a safe assignment, expansion is
6324 -- done by enclosing operation.
6326 Opnd := Relocate_Node (Right_Opnd (N));
6327 Convert_To_Actual_Subtype (Opnd);
6328 Arr := Etype (Opnd);
6329 Ensure_Defined (Arr, N);
6330 Silly_Boolean_Array_Not_Test (N, Arr);
6332 if Nkind (Parent (N)) = N_Assignment_Statement then
6333 if Safe_In_Place_Array_Op (Name (Parent (N)), N, Empty) then
6334 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
6337 -- Special case the negation of a binary operation
6339 elsif Nkind_In (Opnd, N_Op_And, N_Op_Or, N_Op_Xor)
6340 and then Safe_In_Place_Array_Op
6341 (Name (Parent (N)), Left_Opnd (Opnd), Right_Opnd (Opnd))
6343 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
6347 elsif Nkind (Parent (N)) in N_Binary_Op
6348 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
6351 Op1 : constant Node_Id := Left_Opnd (Parent (N));
6352 Op2 : constant Node_Id := Right_Opnd (Parent (N));
6353 Lhs : constant Node_Id := Name (Parent (Parent (N)));
6356 if Safe_In_Place_Array_Op (Lhs, Op1, Op2) then
6358 and then Nkind (Op2) = N_Op_Not
6360 -- (not A) op (not B) can be reduced to a single call
6365 and then Nkind (Parent (N)) = N_Op_Xor
6367 -- A xor (not B) can also be special-cased
6375 A := Make_Defining_Identifier (Loc, Name_uA);
6376 B := Make_Defining_Identifier (Loc, Name_uB);
6377 J := Make_Defining_Identifier (Loc, Name_uJ);
6380 Make_Indexed_Component (Loc,
6381 Prefix => New_Reference_To (A, Loc),
6382 Expressions => New_List (New_Reference_To (J, Loc)));
6385 Make_Indexed_Component (Loc,
6386 Prefix => New_Reference_To (B, Loc),
6387 Expressions => New_List (New_Reference_To (J, Loc)));
6390 Make_Implicit_Loop_Statement (N,
6391 Identifier => Empty,
6394 Make_Iteration_Scheme (Loc,
6395 Loop_Parameter_Specification =>
6396 Make_Loop_Parameter_Specification (Loc,
6397 Defining_Identifier => J,
6398 Discrete_Subtype_Definition =>
6399 Make_Attribute_Reference (Loc,
6400 Prefix => Make_Identifier (Loc, Chars (A)),
6401 Attribute_Name => Name_Range))),
6403 Statements => New_List (
6404 Make_Assignment_Statement (Loc,
6406 Expression => Make_Op_Not (Loc, A_J))));
6408 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('N'));
6409 Set_Is_Inlined (Func_Name);
6412 Make_Subprogram_Body (Loc,
6414 Make_Function_Specification (Loc,
6415 Defining_Unit_Name => Func_Name,
6416 Parameter_Specifications => New_List (
6417 Make_Parameter_Specification (Loc,
6418 Defining_Identifier => A,
6419 Parameter_Type => New_Reference_To (Typ, Loc))),
6420 Result_Definition => New_Reference_To (Typ, Loc)),
6422 Declarations => New_List (
6423 Make_Object_Declaration (Loc,
6424 Defining_Identifier => B,
6425 Object_Definition => New_Reference_To (Arr, Loc))),
6427 Handled_Statement_Sequence =>
6428 Make_Handled_Sequence_Of_Statements (Loc,
6429 Statements => New_List (
6431 Make_Simple_Return_Statement (Loc,
6433 Make_Identifier (Loc, Chars (B)))))));
6436 Make_Function_Call (Loc,
6437 Name => New_Reference_To (Func_Name, Loc),
6438 Parameter_Associations => New_List (Opnd)));
6440 Analyze_And_Resolve (N, Typ);
6441 end Expand_N_Op_Not;
6443 --------------------
6444 -- Expand_N_Op_Or --
6445 --------------------
6447 procedure Expand_N_Op_Or (N : Node_Id) is
6448 Typ : constant Entity_Id := Etype (N);
6451 Binary_Op_Validity_Checks (N);
6453 if Is_Array_Type (Etype (N)) then
6454 Expand_Boolean_Operator (N);
6456 elsif Is_Boolean_Type (Etype (N)) then
6457 Adjust_Condition (Left_Opnd (N));
6458 Adjust_Condition (Right_Opnd (N));
6459 Set_Etype (N, Standard_Boolean);
6460 Adjust_Result_Type (N, Typ);
6464 ----------------------
6465 -- Expand_N_Op_Plus --
6466 ----------------------
6468 procedure Expand_N_Op_Plus (N : Node_Id) is
6470 Unary_Op_Validity_Checks (N);
6471 end Expand_N_Op_Plus;
6473 ---------------------
6474 -- Expand_N_Op_Rem --
6475 ---------------------
6477 procedure Expand_N_Op_Rem (N : Node_Id) is
6478 Loc : constant Source_Ptr := Sloc (N);
6479 Typ : constant Entity_Id := Etype (N);
6481 Left : constant Node_Id := Left_Opnd (N);
6482 Right : constant Node_Id := Right_Opnd (N);
6492 pragma Warnings (Off, Lhi);
6495 Binary_Op_Validity_Checks (N);
6497 if Is_Integer_Type (Etype (N)) then
6498 Apply_Divide_Check (N);
6501 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
6502 -- but it is useful with other back ends (e.g. AAMP), and is certainly
6505 if Is_Integer_Type (Etype (N))
6506 and then Compile_Time_Known_Value (Right)
6507 and then Expr_Value (Right) = Uint_1
6509 -- Call Remove_Side_Effects to ensure that any side effects in the
6510 -- ignored left operand (in particular function calls to user defined
6511 -- functions) are properly executed.
6513 Remove_Side_Effects (Left);
6515 Rewrite (N, Make_Integer_Literal (Loc, 0));
6516 Analyze_And_Resolve (N, Typ);
6520 -- Deal with annoying case of largest negative number remainder minus
6521 -- one. Gigi does not handle this case correctly, because it generates
6522 -- a divide instruction which may trap in this case.
6524 -- In fact the check is quite easy, if the right operand is -1, then
6525 -- the remainder is always 0, and we can just ignore the left operand
6526 -- completely in this case.
6528 Determine_Range (Right, ROK, Rlo, Rhi);
6529 Determine_Range (Left, LOK, Llo, Lhi);
6531 -- The operand type may be private (e.g. in the expansion of an
6532 -- intrinsic operation) so we must use the underlying type to get the
6533 -- bounds, and convert the literals explicitly.
6537 (Type_Low_Bound (Base_Type (Underlying_Type (Etype (Left)))));
6539 -- Now perform the test, generating code only if needed
6541 if ((not ROK) or else (Rlo <= (-1) and then (-1) <= Rhi))
6543 ((not LOK) or else (Llo = LLB))
6546 Make_Conditional_Expression (Loc,
6547 Expressions => New_List (
6549 Left_Opnd => Duplicate_Subexpr (Right),
6551 Unchecked_Convert_To (Typ,
6552 Make_Integer_Literal (Loc, -1))),
6554 Unchecked_Convert_To (Typ,
6555 Make_Integer_Literal (Loc, Uint_0)),
6557 Relocate_Node (N))));
6559 Set_Analyzed (Next (Next (First (Expressions (N)))));
6560 Analyze_And_Resolve (N, Typ);
6562 end Expand_N_Op_Rem;
6564 -----------------------------
6565 -- Expand_N_Op_Rotate_Left --
6566 -----------------------------
6568 procedure Expand_N_Op_Rotate_Left (N : Node_Id) is
6570 Binary_Op_Validity_Checks (N);
6571 end Expand_N_Op_Rotate_Left;
6573 ------------------------------
6574 -- Expand_N_Op_Rotate_Right --
6575 ------------------------------
6577 procedure Expand_N_Op_Rotate_Right (N : Node_Id) is
6579 Binary_Op_Validity_Checks (N);
6580 end Expand_N_Op_Rotate_Right;
6582 ----------------------------
6583 -- Expand_N_Op_Shift_Left --
6584 ----------------------------
6586 procedure Expand_N_Op_Shift_Left (N : Node_Id) is
6588 Binary_Op_Validity_Checks (N);
6589 end Expand_N_Op_Shift_Left;
6591 -----------------------------
6592 -- Expand_N_Op_Shift_Right --
6593 -----------------------------
6595 procedure Expand_N_Op_Shift_Right (N : Node_Id) is
6597 Binary_Op_Validity_Checks (N);
6598 end Expand_N_Op_Shift_Right;
6600 ----------------------------------------
6601 -- Expand_N_Op_Shift_Right_Arithmetic --
6602 ----------------------------------------
6604 procedure Expand_N_Op_Shift_Right_Arithmetic (N : Node_Id) is
6606 Binary_Op_Validity_Checks (N);
6607 end Expand_N_Op_Shift_Right_Arithmetic;
6609 --------------------------
6610 -- Expand_N_Op_Subtract --
6611 --------------------------
6613 procedure Expand_N_Op_Subtract (N : Node_Id) is
6614 Typ : constant Entity_Id := Etype (N);
6617 Binary_Op_Validity_Checks (N);
6619 -- N - 0 = N for integer types
6621 if Is_Integer_Type (Typ)
6622 and then Compile_Time_Known_Value (Right_Opnd (N))
6623 and then Expr_Value (Right_Opnd (N)) = 0
6625 Rewrite (N, Left_Opnd (N));
6629 -- Arithmetic overflow checks for signed integer/fixed point types
6631 if Is_Signed_Integer_Type (Typ)
6632 or else Is_Fixed_Point_Type (Typ)
6634 Apply_Arithmetic_Overflow_Check (N);
6636 -- Vax floating-point types case
6638 elsif Vax_Float (Typ) then
6639 Expand_Vax_Arith (N);
6641 end Expand_N_Op_Subtract;
6643 ---------------------
6644 -- Expand_N_Op_Xor --
6645 ---------------------
6647 procedure Expand_N_Op_Xor (N : Node_Id) is
6648 Typ : constant Entity_Id := Etype (N);
6651 Binary_Op_Validity_Checks (N);
6653 if Is_Array_Type (Etype (N)) then
6654 Expand_Boolean_Operator (N);
6656 elsif Is_Boolean_Type (Etype (N)) then
6657 Adjust_Condition (Left_Opnd (N));
6658 Adjust_Condition (Right_Opnd (N));
6659 Set_Etype (N, Standard_Boolean);
6660 Adjust_Result_Type (N, Typ);
6662 end Expand_N_Op_Xor;
6664 ----------------------
6665 -- Expand_N_Or_Else --
6666 ----------------------
6668 -- Expand into conditional expression if Actions present, and also
6669 -- deal with optimizing case of arguments being True or False.
6671 procedure Expand_N_Or_Else (N : Node_Id) is
6672 Loc : constant Source_Ptr := Sloc (N);
6673 Typ : constant Entity_Id := Etype (N);
6674 Left : constant Node_Id := Left_Opnd (N);
6675 Right : constant Node_Id := Right_Opnd (N);
6679 -- Deal with non-standard booleans
6681 if Is_Boolean_Type (Typ) then
6682 Adjust_Condition (Left);
6683 Adjust_Condition (Right);
6684 Set_Etype (N, Standard_Boolean);
6687 -- Check for cases where left argument is known to be True or False
6689 if Compile_Time_Known_Value (Left) then
6691 -- If left argument is False, change (False or else Right) to Right.
6692 -- Any actions associated with Right will be executed unconditionally
6693 -- and can thus be inserted into the tree unconditionally.
6695 if Expr_Value_E (Left) = Standard_False then
6696 if Present (Actions (N)) then
6697 Insert_Actions (N, Actions (N));
6702 -- If left argument is True, change (True and then Right) to True. In
6703 -- this case we can forget the actions associated with Right, since
6704 -- they will never be executed.
6706 else pragma Assert (Expr_Value_E (Left) = Standard_True);
6707 Kill_Dead_Code (Right);
6708 Kill_Dead_Code (Actions (N));
6709 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
6712 Adjust_Result_Type (N, Typ);
6716 -- If Actions are present, we expand
6718 -- left or else right
6722 -- if left then True else right end
6724 -- with the actions becoming the Else_Actions of the conditional
6725 -- expression. This conditional expression is then further expanded
6726 -- (and will eventually disappear)
6728 if Present (Actions (N)) then
6729 Actlist := Actions (N);
6731 Make_Conditional_Expression (Loc,
6732 Expressions => New_List (
6734 New_Occurrence_Of (Standard_True, Loc),
6737 Set_Else_Actions (N, Actlist);
6738 Analyze_And_Resolve (N, Standard_Boolean);
6739 Adjust_Result_Type (N, Typ);
6743 -- No actions present, check for cases of right argument True/False
6745 if Compile_Time_Known_Value (Right) then
6747 -- Change (Left or else False) to Left. Note that we know there are
6748 -- no actions associated with the True operand, since we just checked
6749 -- for this case above.
6751 if Expr_Value_E (Right) = Standard_False then
6754 -- Change (Left or else True) to True, making sure to preserve any
6755 -- side effects associated with the Left operand.
6757 else pragma Assert (Expr_Value_E (Right) = Standard_True);
6758 Remove_Side_Effects (Left);
6760 (N, New_Occurrence_Of (Standard_True, Loc));
6764 Adjust_Result_Type (N, Typ);
6765 end Expand_N_Or_Else;
6767 -----------------------------------
6768 -- Expand_N_Qualified_Expression --
6769 -----------------------------------
6771 procedure Expand_N_Qualified_Expression (N : Node_Id) is
6772 Operand : constant Node_Id := Expression (N);
6773 Target_Type : constant Entity_Id := Entity (Subtype_Mark (N));
6776 -- Do validity check if validity checking operands
6778 if Validity_Checks_On
6779 and then Validity_Check_Operands
6781 Ensure_Valid (Operand);
6784 -- Apply possible constraint check
6786 Apply_Constraint_Check (Operand, Target_Type, No_Sliding => True);
6787 end Expand_N_Qualified_Expression;
6789 ---------------------------------
6790 -- Expand_N_Selected_Component --
6791 ---------------------------------
6793 -- If the selector is a discriminant of a concurrent object, rewrite the
6794 -- prefix to denote the corresponding record type.
6796 procedure Expand_N_Selected_Component (N : Node_Id) is
6797 Loc : constant Source_Ptr := Sloc (N);
6798 Par : constant Node_Id := Parent (N);
6799 P : constant Node_Id := Prefix (N);
6800 Ptyp : Entity_Id := Underlying_Type (Etype (P));
6805 function In_Left_Hand_Side (Comp : Node_Id) return Boolean;
6806 -- Gigi needs a temporary for prefixes that depend on a discriminant,
6807 -- unless the context of an assignment can provide size information.
6808 -- Don't we have a general routine that does this???
6810 -----------------------
6811 -- In_Left_Hand_Side --
6812 -----------------------
6814 function In_Left_Hand_Side (Comp : Node_Id) return Boolean is
6816 return (Nkind (Parent (Comp)) = N_Assignment_Statement
6817 and then Comp = Name (Parent (Comp)))
6818 or else (Present (Parent (Comp))
6819 and then Nkind (Parent (Comp)) in N_Subexpr
6820 and then In_Left_Hand_Side (Parent (Comp)));
6821 end In_Left_Hand_Side;
6823 -- Start of processing for Expand_N_Selected_Component
6826 -- Insert explicit dereference if required
6828 if Is_Access_Type (Ptyp) then
6829 Insert_Explicit_Dereference (P);
6830 Analyze_And_Resolve (P, Designated_Type (Ptyp));
6832 if Ekind (Etype (P)) = E_Private_Subtype
6833 and then Is_For_Access_Subtype (Etype (P))
6835 Set_Etype (P, Base_Type (Etype (P)));
6841 -- Deal with discriminant check required
6843 if Do_Discriminant_Check (N) then
6845 -- Present the discriminant checking function to the backend, so that
6846 -- it can inline the call to the function.
6849 (Discriminant_Checking_Func
6850 (Original_Record_Component (Entity (Selector_Name (N)))));
6852 -- Now reset the flag and generate the call
6854 Set_Do_Discriminant_Check (N, False);
6855 Generate_Discriminant_Check (N);
6858 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
6859 -- function, then additional actuals must be passed.
6861 if Ada_Version >= Ada_05
6862 and then Is_Build_In_Place_Function_Call (P)
6864 Make_Build_In_Place_Call_In_Anonymous_Context (P);
6867 -- Gigi cannot handle unchecked conversions that are the prefix of a
6868 -- selected component with discriminants. This must be checked during
6869 -- expansion, because during analysis the type of the selector is not
6870 -- known at the point the prefix is analyzed. If the conversion is the
6871 -- target of an assignment, then we cannot force the evaluation.
6873 if Nkind (Prefix (N)) = N_Unchecked_Type_Conversion
6874 and then Has_Discriminants (Etype (N))
6875 and then not In_Left_Hand_Side (N)
6877 Force_Evaluation (Prefix (N));
6880 -- Remaining processing applies only if selector is a discriminant
6882 if Ekind (Entity (Selector_Name (N))) = E_Discriminant then
6884 -- If the selector is a discriminant of a constrained record type,
6885 -- we may be able to rewrite the expression with the actual value
6886 -- of the discriminant, a useful optimization in some cases.
6888 if Is_Record_Type (Ptyp)
6889 and then Has_Discriminants (Ptyp)
6890 and then Is_Constrained (Ptyp)
6892 -- Do this optimization for discrete types only, and not for
6893 -- access types (access discriminants get us into trouble!)
6895 if not Is_Discrete_Type (Etype (N)) then
6898 -- Don't do this on the left hand of an assignment statement.
6899 -- Normally one would think that references like this would
6900 -- not occur, but they do in generated code, and mean that
6901 -- we really do want to assign the discriminant!
6903 elsif Nkind (Par) = N_Assignment_Statement
6904 and then Name (Par) = N
6908 -- Don't do this optimization for the prefix of an attribute or
6909 -- the operand of an object renaming declaration since these are
6910 -- contexts where we do not want the value anyway.
6912 elsif (Nkind (Par) = N_Attribute_Reference
6913 and then Prefix (Par) = N)
6914 or else Is_Renamed_Object (N)
6918 -- Don't do this optimization if we are within the code for a
6919 -- discriminant check, since the whole point of such a check may
6920 -- be to verify the condition on which the code below depends!
6922 elsif Is_In_Discriminant_Check (N) then
6925 -- Green light to see if we can do the optimization. There is
6926 -- still one condition that inhibits the optimization below but
6927 -- now is the time to check the particular discriminant.
6930 -- Loop through discriminants to find the matching discriminant
6931 -- constraint to see if we can copy it.
6933 Disc := First_Discriminant (Ptyp);
6934 Dcon := First_Elmt (Discriminant_Constraint (Ptyp));
6935 Discr_Loop : while Present (Dcon) loop
6937 -- Check if this is the matching discriminant
6939 if Disc = Entity (Selector_Name (N)) then
6941 -- Here we have the matching discriminant. Check for
6942 -- the case of a discriminant of a component that is
6943 -- constrained by an outer discriminant, which cannot
6944 -- be optimized away.
6947 Denotes_Discriminant
6948 (Node (Dcon), Check_Concurrent => True)
6952 -- In the context of a case statement, the expression may
6953 -- have the base type of the discriminant, and we need to
6954 -- preserve the constraint to avoid spurious errors on
6957 elsif Nkind (Parent (N)) = N_Case_Statement
6958 and then Etype (Node (Dcon)) /= Etype (Disc)
6961 Make_Qualified_Expression (Loc,
6963 New_Occurrence_Of (Etype (Disc), Loc),
6965 New_Copy_Tree (Node (Dcon))));
6966 Analyze_And_Resolve (N, Etype (Disc));
6968 -- In case that comes out as a static expression,
6969 -- reset it (a selected component is never static).
6971 Set_Is_Static_Expression (N, False);
6974 -- Otherwise we can just copy the constraint, but the
6975 -- result is certainly not static! In some cases the
6976 -- discriminant constraint has been analyzed in the
6977 -- context of the original subtype indication, but for
6978 -- itypes the constraint might not have been analyzed
6979 -- yet, and this must be done now.
6982 Rewrite (N, New_Copy_Tree (Node (Dcon)));
6983 Analyze_And_Resolve (N);
6984 Set_Is_Static_Expression (N, False);
6990 Next_Discriminant (Disc);
6991 end loop Discr_Loop;
6993 -- Note: the above loop should always find a matching
6994 -- discriminant, but if it does not, we just missed an
6995 -- optimization due to some glitch (perhaps a previous error),
7001 -- The only remaining processing is in the case of a discriminant of
7002 -- a concurrent object, where we rewrite the prefix to denote the
7003 -- corresponding record type. If the type is derived and has renamed
7004 -- discriminants, use corresponding discriminant, which is the one
7005 -- that appears in the corresponding record.
7007 if not Is_Concurrent_Type (Ptyp) then
7011 Disc := Entity (Selector_Name (N));
7013 if Is_Derived_Type (Ptyp)
7014 and then Present (Corresponding_Discriminant (Disc))
7016 Disc := Corresponding_Discriminant (Disc);
7020 Make_Selected_Component (Loc,
7022 Unchecked_Convert_To (Corresponding_Record_Type (Ptyp),
7024 Selector_Name => Make_Identifier (Loc, Chars (Disc)));
7029 end Expand_N_Selected_Component;
7031 --------------------
7032 -- Expand_N_Slice --
7033 --------------------
7035 procedure Expand_N_Slice (N : Node_Id) is
7036 Loc : constant Source_Ptr := Sloc (N);
7037 Typ : constant Entity_Id := Etype (N);
7038 Pfx : constant Node_Id := Prefix (N);
7039 Ptp : Entity_Id := Etype (Pfx);
7041 function Is_Procedure_Actual (N : Node_Id) return Boolean;
7042 -- Check whether the argument is an actual for a procedure call, in
7043 -- which case the expansion of a bit-packed slice is deferred until the
7044 -- call itself is expanded. The reason this is required is that we might
7045 -- have an IN OUT or OUT parameter, and the copy out is essential, and
7046 -- that copy out would be missed if we created a temporary here in
7047 -- Expand_N_Slice. Note that we don't bother to test specifically for an
7048 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
7049 -- is harmless to defer expansion in the IN case, since the call
7050 -- processing will still generate the appropriate copy in operation,
7051 -- which will take care of the slice.
7053 procedure Make_Temporary;
7054 -- Create a named variable for the value of the slice, in cases where
7055 -- the back-end cannot handle it properly, e.g. when packed types or
7056 -- unaligned slices are involved.
7058 -------------------------
7059 -- Is_Procedure_Actual --
7060 -------------------------
7062 function Is_Procedure_Actual (N : Node_Id) return Boolean is
7063 Par : Node_Id := Parent (N);
7067 -- If our parent is a procedure call we can return
7069 if Nkind (Par) = N_Procedure_Call_Statement then
7072 -- If our parent is a type conversion, keep climbing the tree,
7073 -- since a type conversion can be a procedure actual. Also keep
7074 -- climbing if parameter association or a qualified expression,
7075 -- since these are additional cases that do can appear on
7076 -- procedure actuals.
7078 elsif Nkind_In (Par, N_Type_Conversion,
7079 N_Parameter_Association,
7080 N_Qualified_Expression)
7082 Par := Parent (Par);
7084 -- Any other case is not what we are looking for
7090 end Is_Procedure_Actual;
7092 --------------------
7093 -- Make_Temporary --
7094 --------------------
7096 procedure Make_Temporary is
7098 Ent : constant Entity_Id :=
7099 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
7102 Make_Object_Declaration (Loc,
7103 Defining_Identifier => Ent,
7104 Object_Definition => New_Occurrence_Of (Typ, Loc));
7106 Set_No_Initialization (Decl);
7108 Insert_Actions (N, New_List (
7110 Make_Assignment_Statement (Loc,
7111 Name => New_Occurrence_Of (Ent, Loc),
7112 Expression => Relocate_Node (N))));
7114 Rewrite (N, New_Occurrence_Of (Ent, Loc));
7115 Analyze_And_Resolve (N, Typ);
7118 -- Start of processing for Expand_N_Slice
7121 -- Special handling for access types
7123 if Is_Access_Type (Ptp) then
7125 Ptp := Designated_Type (Ptp);
7128 Make_Explicit_Dereference (Sloc (N),
7129 Prefix => Relocate_Node (Pfx)));
7131 Analyze_And_Resolve (Pfx, Ptp);
7134 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7135 -- function, then additional actuals must be passed.
7137 if Ada_Version >= Ada_05
7138 and then Is_Build_In_Place_Function_Call (Pfx)
7140 Make_Build_In_Place_Call_In_Anonymous_Context (Pfx);
7143 -- Range checks are potentially also needed for cases involving a slice
7144 -- indexed by a subtype indication, but Do_Range_Check can currently
7145 -- only be set for expressions ???
7147 if not Index_Checks_Suppressed (Ptp)
7148 and then (not Is_Entity_Name (Pfx)
7149 or else not Index_Checks_Suppressed (Entity (Pfx)))
7150 and then Nkind (Discrete_Range (N)) /= N_Subtype_Indication
7152 -- Do not enable range check to nodes associated with the frontend
7153 -- expansion of the dispatch table. We first check if Ada.Tags is
7154 -- already loaded to avoid the addition of an undesired dependence
7155 -- on such run-time unit.
7160 (RTU_Loaded (Ada_Tags)
7161 and then Nkind (Prefix (N)) = N_Selected_Component
7162 and then Present (Entity (Selector_Name (Prefix (N))))
7163 and then Entity (Selector_Name (Prefix (N))) =
7164 RTE_Record_Component (RE_Prims_Ptr)))
7166 Enable_Range_Check (Discrete_Range (N));
7169 -- The remaining case to be handled is packed slices. We can leave
7170 -- packed slices as they are in the following situations:
7172 -- 1. Right or left side of an assignment (we can handle this
7173 -- situation correctly in the assignment statement expansion).
7175 -- 2. Prefix of indexed component (the slide is optimized away in this
7176 -- case, see the start of Expand_N_Slice.)
7178 -- 3. Object renaming declaration, since we want the name of the
7179 -- slice, not the value.
7181 -- 4. Argument to procedure call, since copy-in/copy-out handling may
7182 -- be required, and this is handled in the expansion of call
7185 -- 5. Prefix of an address attribute (this is an error which is caught
7186 -- elsewhere, and the expansion would interfere with generating the
7189 if not Is_Packed (Typ) then
7191 -- Apply transformation for actuals of a function call, where
7192 -- Expand_Actuals is not used.
7194 if Nkind (Parent (N)) = N_Function_Call
7195 and then Is_Possibly_Unaligned_Slice (N)
7200 elsif Nkind (Parent (N)) = N_Assignment_Statement
7201 or else (Nkind (Parent (Parent (N))) = N_Assignment_Statement
7202 and then Parent (N) = Name (Parent (Parent (N))))
7206 elsif Nkind (Parent (N)) = N_Indexed_Component
7207 or else Is_Renamed_Object (N)
7208 or else Is_Procedure_Actual (N)
7212 elsif Nkind (Parent (N)) = N_Attribute_Reference
7213 and then Attribute_Name (Parent (N)) = Name_Address
7222 ------------------------------
7223 -- Expand_N_Type_Conversion --
7224 ------------------------------
7226 procedure Expand_N_Type_Conversion (N : Node_Id) is
7227 Loc : constant Source_Ptr := Sloc (N);
7228 Operand : constant Node_Id := Expression (N);
7229 Target_Type : constant Entity_Id := Etype (N);
7230 Operand_Type : Entity_Id := Etype (Operand);
7232 procedure Handle_Changed_Representation;
7233 -- This is called in the case of record and array type conversions to
7234 -- see if there is a change of representation to be handled. Change of
7235 -- representation is actually handled at the assignment statement level,
7236 -- and what this procedure does is rewrite node N conversion as an
7237 -- assignment to temporary. If there is no change of representation,
7238 -- then the conversion node is unchanged.
7240 procedure Real_Range_Check;
7241 -- Handles generation of range check for real target value
7243 -----------------------------------
7244 -- Handle_Changed_Representation --
7245 -----------------------------------
7247 procedure Handle_Changed_Representation is
7256 -- Nothing else to do if no change of representation
7258 if Same_Representation (Operand_Type, Target_Type) then
7261 -- The real change of representation work is done by the assignment
7262 -- statement processing. So if this type conversion is appearing as
7263 -- the expression of an assignment statement, nothing needs to be
7264 -- done to the conversion.
7266 elsif Nkind (Parent (N)) = N_Assignment_Statement then
7269 -- Otherwise we need to generate a temporary variable, and do the
7270 -- change of representation assignment into that temporary variable.
7271 -- The conversion is then replaced by a reference to this variable.
7276 -- If type is unconstrained we have to add a constraint, copied
7277 -- from the actual value of the left hand side.
7279 if not Is_Constrained (Target_Type) then
7280 if Has_Discriminants (Operand_Type) then
7281 Disc := First_Discriminant (Operand_Type);
7283 if Disc /= First_Stored_Discriminant (Operand_Type) then
7284 Disc := First_Stored_Discriminant (Operand_Type);
7288 while Present (Disc) loop
7290 Make_Selected_Component (Loc,
7291 Prefix => Duplicate_Subexpr_Move_Checks (Operand),
7293 Make_Identifier (Loc, Chars (Disc))));
7294 Next_Discriminant (Disc);
7297 elsif Is_Array_Type (Operand_Type) then
7298 N_Ix := First_Index (Target_Type);
7301 for J in 1 .. Number_Dimensions (Operand_Type) loop
7303 -- We convert the bounds explicitly. We use an unchecked
7304 -- conversion because bounds checks are done elsewhere.
7309 Unchecked_Convert_To (Etype (N_Ix),
7310 Make_Attribute_Reference (Loc,
7312 Duplicate_Subexpr_No_Checks
7313 (Operand, Name_Req => True),
7314 Attribute_Name => Name_First,
7315 Expressions => New_List (
7316 Make_Integer_Literal (Loc, J)))),
7319 Unchecked_Convert_To (Etype (N_Ix),
7320 Make_Attribute_Reference (Loc,
7322 Duplicate_Subexpr_No_Checks
7323 (Operand, Name_Req => True),
7324 Attribute_Name => Name_Last,
7325 Expressions => New_List (
7326 Make_Integer_Literal (Loc, J))))));
7333 Odef := New_Occurrence_Of (Target_Type, Loc);
7335 if Present (Cons) then
7337 Make_Subtype_Indication (Loc,
7338 Subtype_Mark => Odef,
7340 Make_Index_Or_Discriminant_Constraint (Loc,
7341 Constraints => Cons));
7344 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
7346 Make_Object_Declaration (Loc,
7347 Defining_Identifier => Temp,
7348 Object_Definition => Odef);
7350 Set_No_Initialization (Decl, True);
7352 -- Insert required actions. It is essential to suppress checks
7353 -- since we have suppressed default initialization, which means
7354 -- that the variable we create may have no discriminants.
7359 Make_Assignment_Statement (Loc,
7360 Name => New_Occurrence_Of (Temp, Loc),
7361 Expression => Relocate_Node (N))),
7362 Suppress => All_Checks);
7364 Rewrite (N, New_Occurrence_Of (Temp, Loc));
7367 end Handle_Changed_Representation;
7369 ----------------------
7370 -- Real_Range_Check --
7371 ----------------------
7373 -- Case of conversions to floating-point or fixed-point. If range checks
7374 -- are enabled and the target type has a range constraint, we convert:
7380 -- Tnn : typ'Base := typ'Base (x);
7381 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
7384 -- This is necessary when there is a conversion of integer to float or
7385 -- to fixed-point to ensure that the correct checks are made. It is not
7386 -- necessary for float to float where it is enough to simply set the
7387 -- Do_Range_Check flag.
7389 procedure Real_Range_Check is
7390 Btyp : constant Entity_Id := Base_Type (Target_Type);
7391 Lo : constant Node_Id := Type_Low_Bound (Target_Type);
7392 Hi : constant Node_Id := Type_High_Bound (Target_Type);
7393 Xtyp : constant Entity_Id := Etype (Operand);
7398 -- Nothing to do if conversion was rewritten
7400 if Nkind (N) /= N_Type_Conversion then
7404 -- Nothing to do if range checks suppressed, or target has the same
7405 -- range as the base type (or is the base type).
7407 if Range_Checks_Suppressed (Target_Type)
7408 or else (Lo = Type_Low_Bound (Btyp)
7410 Hi = Type_High_Bound (Btyp))
7415 -- Nothing to do if expression is an entity on which checks have been
7418 if Is_Entity_Name (Operand)
7419 and then Range_Checks_Suppressed (Entity (Operand))
7424 -- Nothing to do if bounds are all static and we can tell that the
7425 -- expression is within the bounds of the target. Note that if the
7426 -- operand is of an unconstrained floating-point type, then we do
7427 -- not trust it to be in range (might be infinite)
7430 S_Lo : constant Node_Id := Type_Low_Bound (Xtyp);
7431 S_Hi : constant Node_Id := Type_High_Bound (Xtyp);
7434 if (not Is_Floating_Point_Type (Xtyp)
7435 or else Is_Constrained (Xtyp))
7436 and then Compile_Time_Known_Value (S_Lo)
7437 and then Compile_Time_Known_Value (S_Hi)
7438 and then Compile_Time_Known_Value (Hi)
7439 and then Compile_Time_Known_Value (Lo)
7442 D_Lov : constant Ureal := Expr_Value_R (Lo);
7443 D_Hiv : constant Ureal := Expr_Value_R (Hi);
7448 if Is_Real_Type (Xtyp) then
7449 S_Lov := Expr_Value_R (S_Lo);
7450 S_Hiv := Expr_Value_R (S_Hi);
7452 S_Lov := UR_From_Uint (Expr_Value (S_Lo));
7453 S_Hiv := UR_From_Uint (Expr_Value (S_Hi));
7457 and then S_Lov >= D_Lov
7458 and then S_Hiv <= D_Hiv
7460 Set_Do_Range_Check (Operand, False);
7467 -- For float to float conversions, we are done
7469 if Is_Floating_Point_Type (Xtyp)
7471 Is_Floating_Point_Type (Btyp)
7476 -- Otherwise rewrite the conversion as described above
7478 Conv := Relocate_Node (N);
7480 (Subtype_Mark (Conv), New_Occurrence_Of (Btyp, Loc));
7481 Set_Etype (Conv, Btyp);
7483 -- Enable overflow except for case of integer to float conversions,
7484 -- where it is never required, since we can never have overflow in
7487 if not Is_Integer_Type (Etype (Operand)) then
7488 Enable_Overflow_Check (Conv);
7492 Make_Defining_Identifier (Loc,
7493 Chars => New_Internal_Name ('T'));
7495 Insert_Actions (N, New_List (
7496 Make_Object_Declaration (Loc,
7497 Defining_Identifier => Tnn,
7498 Object_Definition => New_Occurrence_Of (Btyp, Loc),
7499 Expression => Conv),
7501 Make_Raise_Constraint_Error (Loc,
7506 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
7508 Make_Attribute_Reference (Loc,
7509 Attribute_Name => Name_First,
7511 New_Occurrence_Of (Target_Type, Loc))),
7515 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
7517 Make_Attribute_Reference (Loc,
7518 Attribute_Name => Name_Last,
7520 New_Occurrence_Of (Target_Type, Loc)))),
7521 Reason => CE_Range_Check_Failed)));
7523 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
7524 Analyze_And_Resolve (N, Btyp);
7525 end Real_Range_Check;
7527 -- Start of processing for Expand_N_Type_Conversion
7530 -- Nothing at all to do if conversion is to the identical type so remove
7531 -- the conversion completely, it is useless.
7533 if Operand_Type = Target_Type then
7534 Rewrite (N, Relocate_Node (Operand));
7538 -- Nothing to do if this is the second argument of read. This is a
7539 -- "backwards" conversion that will be handled by the specialized code
7540 -- in attribute processing.
7542 if Nkind (Parent (N)) = N_Attribute_Reference
7543 and then Attribute_Name (Parent (N)) = Name_Read
7544 and then Next (First (Expressions (Parent (N)))) = N
7549 -- Here if we may need to expand conversion
7551 -- Do validity check if validity checking operands
7553 if Validity_Checks_On
7554 and then Validity_Check_Operands
7556 Ensure_Valid (Operand);
7559 -- Special case of converting from non-standard boolean type
7561 if Is_Boolean_Type (Operand_Type)
7562 and then (Nonzero_Is_True (Operand_Type))
7564 Adjust_Condition (Operand);
7565 Set_Etype (Operand, Standard_Boolean);
7566 Operand_Type := Standard_Boolean;
7569 -- Case of converting to an access type
7571 if Is_Access_Type (Target_Type) then
7573 -- Apply an accessibility check when the conversion operand is an
7574 -- access parameter (or a renaming thereof), unless conversion was
7575 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
7576 -- Note that other checks may still need to be applied below (such
7577 -- as tagged type checks).
7579 if Is_Entity_Name (Operand)
7581 (Is_Formal (Entity (Operand))
7583 (Present (Renamed_Object (Entity (Operand)))
7584 and then Is_Entity_Name (Renamed_Object (Entity (Operand)))
7586 (Entity (Renamed_Object (Entity (Operand))))))
7587 and then Ekind (Etype (Operand)) = E_Anonymous_Access_Type
7588 and then (Nkind (Original_Node (N)) /= N_Attribute_Reference
7589 or else Attribute_Name (Original_Node (N)) = Name_Access)
7591 Apply_Accessibility_Check
7592 (Operand, Target_Type, Insert_Node => Operand);
7594 -- If the level of the operand type is statically deeper than the
7595 -- level of the target type, then force Program_Error. Note that this
7596 -- can only occur for cases where the attribute is within the body of
7597 -- an instantiation (otherwise the conversion will already have been
7598 -- rejected as illegal). Note: warnings are issued by the analyzer
7599 -- for the instance cases.
7601 elsif In_Instance_Body
7602 and then Type_Access_Level (Operand_Type) >
7603 Type_Access_Level (Target_Type)
7606 Make_Raise_Program_Error (Sloc (N),
7607 Reason => PE_Accessibility_Check_Failed));
7608 Set_Etype (N, Target_Type);
7610 -- When the operand is a selected access discriminant the check needs
7611 -- to be made against the level of the object denoted by the prefix
7612 -- of the selected name. Force Program_Error for this case as well
7613 -- (this accessibility violation can only happen if within the body
7614 -- of an instantiation).
7616 elsif In_Instance_Body
7617 and then Ekind (Operand_Type) = E_Anonymous_Access_Type
7618 and then Nkind (Operand) = N_Selected_Component
7619 and then Object_Access_Level (Operand) >
7620 Type_Access_Level (Target_Type)
7623 Make_Raise_Program_Error (Sloc (N),
7624 Reason => PE_Accessibility_Check_Failed));
7625 Set_Etype (N, Target_Type);
7629 -- Case of conversions of tagged types and access to tagged types
7631 -- When needed, that is to say when the expression is class-wide, Add
7632 -- runtime a tag check for (strict) downward conversion by using the
7633 -- membership test, generating:
7635 -- [constraint_error when Operand not in Target_Type'Class]
7637 -- or in the access type case
7639 -- [constraint_error
7640 -- when Operand /= null
7641 -- and then Operand.all not in
7642 -- Designated_Type (Target_Type)'Class]
7644 if (Is_Access_Type (Target_Type)
7645 and then Is_Tagged_Type (Designated_Type (Target_Type)))
7646 or else Is_Tagged_Type (Target_Type)
7648 -- Do not do any expansion in the access type case if the parent is a
7649 -- renaming, since this is an error situation which will be caught by
7650 -- Sem_Ch8, and the expansion can interfere with this error check.
7652 if Is_Access_Type (Target_Type)
7653 and then Is_Renamed_Object (N)
7658 -- Otherwise, proceed with processing tagged conversion
7661 Actual_Op_Typ : Entity_Id;
7662 Actual_Targ_Typ : Entity_Id;
7663 Make_Conversion : Boolean := False;
7664 Root_Op_Typ : Entity_Id;
7666 procedure Make_Tag_Check (Targ_Typ : Entity_Id);
7667 -- Create a membership check to test whether Operand is a member
7668 -- of Targ_Typ. If the original Target_Type is an access, include
7669 -- a test for null value. The check is inserted at N.
7671 --------------------
7672 -- Make_Tag_Check --
7673 --------------------
7675 procedure Make_Tag_Check (Targ_Typ : Entity_Id) is
7680 -- [Constraint_Error
7681 -- when Operand /= null
7682 -- and then Operand.all not in Targ_Typ]
7684 if Is_Access_Type (Target_Type) then
7689 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
7690 Right_Opnd => Make_Null (Loc)),
7695 Make_Explicit_Dereference (Loc,
7696 Prefix => Duplicate_Subexpr_No_Checks (Operand)),
7697 Right_Opnd => New_Reference_To (Targ_Typ, Loc)));
7700 -- [Constraint_Error when Operand not in Targ_Typ]
7705 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
7706 Right_Opnd => New_Reference_To (Targ_Typ, Loc));
7710 Make_Raise_Constraint_Error (Loc,
7712 Reason => CE_Tag_Check_Failed));
7715 -- Start of processing
7718 if Is_Access_Type (Target_Type) then
7719 Actual_Op_Typ := Designated_Type (Operand_Type);
7720 Actual_Targ_Typ := Designated_Type (Target_Type);
7723 Actual_Op_Typ := Operand_Type;
7724 Actual_Targ_Typ := Target_Type;
7727 Root_Op_Typ := Root_Type (Actual_Op_Typ);
7729 -- Ada 2005 (AI-251): Handle interface type conversion
7731 if Is_Interface (Actual_Op_Typ) then
7732 Expand_Interface_Conversion (N, Is_Static => False);
7736 if not Tag_Checks_Suppressed (Actual_Targ_Typ) then
7738 -- Create a runtime tag check for a downward class-wide type
7741 if Is_Class_Wide_Type (Actual_Op_Typ)
7742 and then Root_Op_Typ /= Actual_Targ_Typ
7743 and then Is_Ancestor (Root_Op_Typ, Actual_Targ_Typ)
7745 Make_Tag_Check (Class_Wide_Type (Actual_Targ_Typ));
7746 Make_Conversion := True;
7749 -- AI05-0073: If the result subtype of the function is defined
7750 -- by an access_definition designating a specific tagged type
7751 -- T, a check is made that the result value is null or the tag
7752 -- of the object designated by the result value identifies T.
7753 -- Constraint_Error is raised if this check fails.
7755 if Nkind (Parent (N)) = Sinfo.N_Return_Statement then
7758 Func_Typ : Entity_Id;
7761 -- Climb scope stack looking for the enclosing function
7763 Func := Current_Scope;
7764 while Present (Func)
7765 and then Ekind (Func) /= E_Function
7767 Func := Scope (Func);
7770 -- The function's return subtype must be defined using
7771 -- an access definition.
7773 if Nkind (Result_Definition (Parent (Func))) =
7776 Func_Typ := Directly_Designated_Type (Etype (Func));
7778 -- The return subtype denotes a specific tagged type,
7779 -- in other words, a non class-wide type.
7781 if Is_Tagged_Type (Func_Typ)
7782 and then not Is_Class_Wide_Type (Func_Typ)
7784 Make_Tag_Check (Actual_Targ_Typ);
7785 Make_Conversion := True;
7791 -- We have generated a tag check for either a class-wide type
7792 -- conversion or for AI05-0073.
7794 if Make_Conversion then
7799 Make_Unchecked_Type_Conversion (Loc,
7800 Subtype_Mark => New_Occurrence_Of (Target_Type, Loc),
7801 Expression => Relocate_Node (Expression (N)));
7803 Analyze_And_Resolve (N, Target_Type);
7809 -- Case of other access type conversions
7811 elsif Is_Access_Type (Target_Type) then
7812 Apply_Constraint_Check (Operand, Target_Type);
7814 -- Case of conversions from a fixed-point type
7816 -- These conversions require special expansion and processing, found in
7817 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
7818 -- since from a semantic point of view, these are simple integer
7819 -- conversions, which do not need further processing.
7821 elsif Is_Fixed_Point_Type (Operand_Type)
7822 and then not Conversion_OK (N)
7824 -- We should never see universal fixed at this case, since the
7825 -- expansion of the constituent divide or multiply should have
7826 -- eliminated the explicit mention of universal fixed.
7828 pragma Assert (Operand_Type /= Universal_Fixed);
7830 -- Check for special case of the conversion to universal real that
7831 -- occurs as a result of the use of a round attribute. In this case,
7832 -- the real type for the conversion is taken from the target type of
7833 -- the Round attribute and the result must be marked as rounded.
7835 if Target_Type = Universal_Real
7836 and then Nkind (Parent (N)) = N_Attribute_Reference
7837 and then Attribute_Name (Parent (N)) = Name_Round
7839 Set_Rounded_Result (N);
7840 Set_Etype (N, Etype (Parent (N)));
7843 -- Otherwise do correct fixed-conversion, but skip these if the
7844 -- Conversion_OK flag is set, because from a semantic point of
7845 -- view these are simple integer conversions needing no further
7846 -- processing (the backend will simply treat them as integers)
7848 if not Conversion_OK (N) then
7849 if Is_Fixed_Point_Type (Etype (N)) then
7850 Expand_Convert_Fixed_To_Fixed (N);
7853 elsif Is_Integer_Type (Etype (N)) then
7854 Expand_Convert_Fixed_To_Integer (N);
7857 pragma Assert (Is_Floating_Point_Type (Etype (N)));
7858 Expand_Convert_Fixed_To_Float (N);
7863 -- Case of conversions to a fixed-point type
7865 -- These conversions require special expansion and processing, found in
7866 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
7867 -- since from a semantic point of view, these are simple integer
7868 -- conversions, which do not need further processing.
7870 elsif Is_Fixed_Point_Type (Target_Type)
7871 and then not Conversion_OK (N)
7873 if Is_Integer_Type (Operand_Type) then
7874 Expand_Convert_Integer_To_Fixed (N);
7877 pragma Assert (Is_Floating_Point_Type (Operand_Type));
7878 Expand_Convert_Float_To_Fixed (N);
7882 -- Case of float-to-integer conversions
7884 -- We also handle float-to-fixed conversions with Conversion_OK set
7885 -- since semantically the fixed-point target is treated as though it
7886 -- were an integer in such cases.
7888 elsif Is_Floating_Point_Type (Operand_Type)
7890 (Is_Integer_Type (Target_Type)
7892 (Is_Fixed_Point_Type (Target_Type) and then Conversion_OK (N)))
7894 -- One more check here, gcc is still not able to do conversions of
7895 -- this type with proper overflow checking, and so gigi is doing an
7896 -- approximation of what is required by doing floating-point compares
7897 -- with the end-point. But that can lose precision in some cases, and
7898 -- give a wrong result. Converting the operand to Universal_Real is
7899 -- helpful, but still does not catch all cases with 64-bit integers
7900 -- on targets with only 64-bit floats
7902 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
7903 -- Can this code be removed ???
7905 if Do_Range_Check (Operand) then
7907 Make_Type_Conversion (Loc,
7909 New_Occurrence_Of (Universal_Real, Loc),
7911 Relocate_Node (Operand)));
7913 Set_Etype (Operand, Universal_Real);
7914 Enable_Range_Check (Operand);
7915 Set_Do_Range_Check (Expression (Operand), False);
7918 -- Case of array conversions
7920 -- Expansion of array conversions, add required length/range checks but
7921 -- only do this if there is no change of representation. For handling of
7922 -- this case, see Handle_Changed_Representation.
7924 elsif Is_Array_Type (Target_Type) then
7926 if Is_Constrained (Target_Type) then
7927 Apply_Length_Check (Operand, Target_Type);
7929 Apply_Range_Check (Operand, Target_Type);
7932 Handle_Changed_Representation;
7934 -- Case of conversions of discriminated types
7936 -- Add required discriminant checks if target is constrained. Again this
7937 -- change is skipped if we have a change of representation.
7939 elsif Has_Discriminants (Target_Type)
7940 and then Is_Constrained (Target_Type)
7942 Apply_Discriminant_Check (Operand, Target_Type);
7943 Handle_Changed_Representation;
7945 -- Case of all other record conversions. The only processing required
7946 -- is to check for a change of representation requiring the special
7947 -- assignment processing.
7949 elsif Is_Record_Type (Target_Type) then
7951 -- Ada 2005 (AI-216): Program_Error is raised when converting from
7952 -- a derived Unchecked_Union type to an unconstrained type that is
7953 -- not Unchecked_Union if the operand lacks inferable discriminants.
7955 if Is_Derived_Type (Operand_Type)
7956 and then Is_Unchecked_Union (Base_Type (Operand_Type))
7957 and then not Is_Constrained (Target_Type)
7958 and then not Is_Unchecked_Union (Base_Type (Target_Type))
7959 and then not Has_Inferable_Discriminants (Operand)
7961 -- To prevent Gigi from generating illegal code, we generate a
7962 -- Program_Error node, but we give it the target type of the
7966 PE : constant Node_Id := Make_Raise_Program_Error (Loc,
7967 Reason => PE_Unchecked_Union_Restriction);
7970 Set_Etype (PE, Target_Type);
7975 Handle_Changed_Representation;
7978 -- Case of conversions of enumeration types
7980 elsif Is_Enumeration_Type (Target_Type) then
7982 -- Special processing is required if there is a change of
7983 -- representation (from enumeration representation clauses)
7985 if not Same_Representation (Target_Type, Operand_Type) then
7987 -- Convert: x(y) to x'val (ytyp'val (y))
7990 Make_Attribute_Reference (Loc,
7991 Prefix => New_Occurrence_Of (Target_Type, Loc),
7992 Attribute_Name => Name_Val,
7993 Expressions => New_List (
7994 Make_Attribute_Reference (Loc,
7995 Prefix => New_Occurrence_Of (Operand_Type, Loc),
7996 Attribute_Name => Name_Pos,
7997 Expressions => New_List (Operand)))));
7999 Analyze_And_Resolve (N, Target_Type);
8002 -- Case of conversions to floating-point
8004 elsif Is_Floating_Point_Type (Target_Type) then
8008 -- At this stage, either the conversion node has been transformed into
8009 -- some other equivalent expression, or left as a conversion that can
8010 -- be handled by Gigi. The conversions that Gigi can handle are the
8013 -- Conversions with no change of representation or type
8015 -- Numeric conversions involving integer, floating- and fixed-point
8016 -- values. Fixed-point values are allowed only if Conversion_OK is
8017 -- set, i.e. if the fixed-point values are to be treated as integers.
8019 -- No other conversions should be passed to Gigi
8021 -- Check: are these rules stated in sinfo??? if so, why restate here???
8023 -- The only remaining step is to generate a range check if we still have
8024 -- a type conversion at this stage and Do_Range_Check is set. For now we
8025 -- do this only for conversions of discrete types.
8027 if Nkind (N) = N_Type_Conversion
8028 and then Is_Discrete_Type (Etype (N))
8031 Expr : constant Node_Id := Expression (N);
8036 if Do_Range_Check (Expr)
8037 and then Is_Discrete_Type (Etype (Expr))
8039 Set_Do_Range_Check (Expr, False);
8041 -- Before we do a range check, we have to deal with treating a
8042 -- fixed-point operand as an integer. The way we do this is
8043 -- simply to do an unchecked conversion to an appropriate
8044 -- integer type large enough to hold the result.
8046 -- This code is not active yet, because we are only dealing
8047 -- with discrete types so far ???
8049 if Nkind (Expr) in N_Has_Treat_Fixed_As_Integer
8050 and then Treat_Fixed_As_Integer (Expr)
8052 Ftyp := Base_Type (Etype (Expr));
8054 if Esize (Ftyp) >= Esize (Standard_Integer) then
8055 Ityp := Standard_Long_Long_Integer;
8057 Ityp := Standard_Integer;
8060 Rewrite (Expr, Unchecked_Convert_To (Ityp, Expr));
8063 -- Reset overflow flag, since the range check will include
8064 -- dealing with possible overflow, and generate the check If
8065 -- Address is either a source type or target type, suppress
8066 -- range check to avoid typing anomalies when it is a visible
8069 Set_Do_Overflow_Check (N, False);
8070 if not Is_Descendent_Of_Address (Etype (Expr))
8071 and then not Is_Descendent_Of_Address (Target_Type)
8073 Generate_Range_Check
8074 (Expr, Target_Type, CE_Range_Check_Failed);
8080 -- Final step, if the result is a type conversion involving Vax_Float
8081 -- types, then it is subject for further special processing.
8083 if Nkind (N) = N_Type_Conversion
8084 and then (Vax_Float (Operand_Type) or else Vax_Float (Target_Type))
8086 Expand_Vax_Conversion (N);
8089 end Expand_N_Type_Conversion;
8091 -----------------------------------
8092 -- Expand_N_Unchecked_Expression --
8093 -----------------------------------
8095 -- Remove the unchecked expression node from the tree. It's job was simply
8096 -- to make sure that its constituent expression was handled with checks
8097 -- off, and now that that is done, we can remove it from the tree, and
8098 -- indeed must, since gigi does not expect to see these nodes.
8100 procedure Expand_N_Unchecked_Expression (N : Node_Id) is
8101 Exp : constant Node_Id := Expression (N);
8104 Set_Assignment_OK (Exp, Assignment_OK (N) or Assignment_OK (Exp));
8106 end Expand_N_Unchecked_Expression;
8108 ----------------------------------------
8109 -- Expand_N_Unchecked_Type_Conversion --
8110 ----------------------------------------
8112 -- If this cannot be handled by Gigi and we haven't already made a
8113 -- temporary for it, do it now.
8115 procedure Expand_N_Unchecked_Type_Conversion (N : Node_Id) is
8116 Target_Type : constant Entity_Id := Etype (N);
8117 Operand : constant Node_Id := Expression (N);
8118 Operand_Type : constant Entity_Id := Etype (Operand);
8121 -- If we have a conversion of a compile time known value to a target
8122 -- type and the value is in range of the target type, then we can simply
8123 -- replace the construct by an integer literal of the correct type. We
8124 -- only apply this to integer types being converted. Possibly it may
8125 -- apply in other cases, but it is too much trouble to worry about.
8127 -- Note that we do not do this transformation if the Kill_Range_Check
8128 -- flag is set, since then the value may be outside the expected range.
8129 -- This happens in the Normalize_Scalars case.
8131 -- We also skip this if either the target or operand type is biased
8132 -- because in this case, the unchecked conversion is supposed to
8133 -- preserve the bit pattern, not the integer value.
8135 if Is_Integer_Type (Target_Type)
8136 and then not Has_Biased_Representation (Target_Type)
8137 and then Is_Integer_Type (Operand_Type)
8138 and then not Has_Biased_Representation (Operand_Type)
8139 and then Compile_Time_Known_Value (Operand)
8140 and then not Kill_Range_Check (N)
8143 Val : constant Uint := Expr_Value (Operand);
8146 if Compile_Time_Known_Value (Type_Low_Bound (Target_Type))
8148 Compile_Time_Known_Value (Type_High_Bound (Target_Type))
8150 Val >= Expr_Value (Type_Low_Bound (Target_Type))
8152 Val <= Expr_Value (Type_High_Bound (Target_Type))
8154 Rewrite (N, Make_Integer_Literal (Sloc (N), Val));
8156 -- If Address is the target type, just set the type to avoid a
8157 -- spurious type error on the literal when Address is a visible
8160 if Is_Descendent_Of_Address (Target_Type) then
8161 Set_Etype (N, Target_Type);
8163 Analyze_And_Resolve (N, Target_Type);
8171 -- Nothing to do if conversion is safe
8173 if Safe_Unchecked_Type_Conversion (N) then
8177 -- Otherwise force evaluation unless Assignment_OK flag is set (this
8178 -- flag indicates ??? -- more comments needed here)
8180 if Assignment_OK (N) then
8183 Force_Evaluation (N);
8185 end Expand_N_Unchecked_Type_Conversion;
8187 ----------------------------
8188 -- Expand_Record_Equality --
8189 ----------------------------
8191 -- For non-variant records, Equality is expanded when needed into:
8193 -- and then Lhs.Discr1 = Rhs.Discr1
8195 -- and then Lhs.Discrn = Rhs.Discrn
8196 -- and then Lhs.Cmp1 = Rhs.Cmp1
8198 -- and then Lhs.Cmpn = Rhs.Cmpn
8200 -- The expression is folded by the back-end for adjacent fields. This
8201 -- function is called for tagged record in only one occasion: for imple-
8202 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
8203 -- otherwise the primitive "=" is used directly.
8205 function Expand_Record_Equality
8210 Bodies : List_Id) return Node_Id
8212 Loc : constant Source_Ptr := Sloc (Nod);
8217 First_Time : Boolean := True;
8219 function Suitable_Element (C : Entity_Id) return Entity_Id;
8220 -- Return the first field to compare beginning with C, skipping the
8221 -- inherited components.
8223 ----------------------
8224 -- Suitable_Element --
8225 ----------------------
8227 function Suitable_Element (C : Entity_Id) return Entity_Id is
8232 elsif Ekind (C) /= E_Discriminant
8233 and then Ekind (C) /= E_Component
8235 return Suitable_Element (Next_Entity (C));
8237 elsif Is_Tagged_Type (Typ)
8238 and then C /= Original_Record_Component (C)
8240 return Suitable_Element (Next_Entity (C));
8242 elsif Chars (C) = Name_uController
8243 or else Chars (C) = Name_uTag
8245 return Suitable_Element (Next_Entity (C));
8247 elsif Is_Interface (Etype (C)) then
8248 return Suitable_Element (Next_Entity (C));
8253 end Suitable_Element;
8255 -- Start of processing for Expand_Record_Equality
8258 -- Generates the following code: (assuming that Typ has one Discr and
8259 -- component C2 is also a record)
8262 -- and then Lhs.Discr1 = Rhs.Discr1
8263 -- and then Lhs.C1 = Rhs.C1
8264 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
8266 -- and then Lhs.Cmpn = Rhs.Cmpn
8268 Result := New_Reference_To (Standard_True, Loc);
8269 C := Suitable_Element (First_Entity (Typ));
8271 while Present (C) loop
8279 First_Time := False;
8283 New_Lhs := New_Copy_Tree (Lhs);
8284 New_Rhs := New_Copy_Tree (Rhs);
8288 Expand_Composite_Equality (Nod, Etype (C),
8290 Make_Selected_Component (Loc,
8292 Selector_Name => New_Reference_To (C, Loc)),
8294 Make_Selected_Component (Loc,
8296 Selector_Name => New_Reference_To (C, Loc)),
8299 -- If some (sub)component is an unchecked_union, the whole
8300 -- operation will raise program error.
8302 if Nkind (Check) = N_Raise_Program_Error then
8304 Set_Etype (Result, Standard_Boolean);
8309 Left_Opnd => Result,
8310 Right_Opnd => Check);
8314 C := Suitable_Element (Next_Entity (C));
8318 end Expand_Record_Equality;
8320 -------------------------------------
8321 -- Fixup_Universal_Fixed_Operation --
8322 -------------------------------------
8324 procedure Fixup_Universal_Fixed_Operation (N : Node_Id) is
8325 Conv : constant Node_Id := Parent (N);
8328 -- We must have a type conversion immediately above us
8330 pragma Assert (Nkind (Conv) = N_Type_Conversion);
8332 -- Normally the type conversion gives our target type. The exception
8333 -- occurs in the case of the Round attribute, where the conversion
8334 -- will be to universal real, and our real type comes from the Round
8335 -- attribute (as well as an indication that we must round the result)
8337 if Nkind (Parent (Conv)) = N_Attribute_Reference
8338 and then Attribute_Name (Parent (Conv)) = Name_Round
8340 Set_Etype (N, Etype (Parent (Conv)));
8341 Set_Rounded_Result (N);
8343 -- Normal case where type comes from conversion above us
8346 Set_Etype (N, Etype (Conv));
8348 end Fixup_Universal_Fixed_Operation;
8350 ------------------------------
8351 -- Get_Allocator_Final_List --
8352 ------------------------------
8354 function Get_Allocator_Final_List
8357 PtrT : Entity_Id) return Entity_Id
8359 Loc : constant Source_Ptr := Sloc (N);
8361 Owner : Entity_Id := PtrT;
8362 -- The entity whose finalization list must be used to attach the
8363 -- allocated object.
8366 if Ekind (PtrT) = E_Anonymous_Access_Type then
8368 -- If the context is an access parameter, we need to create a
8369 -- non-anonymous access type in order to have a usable final list,
8370 -- because there is otherwise no pool to which the allocated object
8371 -- can belong. We create both the type and the finalization chain
8372 -- here, because freezing an internal type does not create such a
8373 -- chain. The Final_Chain that is thus created is shared by the
8374 -- access parameter. The access type is tested against the result
8375 -- type of the function to exclude allocators whose type is an
8376 -- anonymous access result type. We freeze the type at once to
8377 -- ensure that it is properly decorated for the back-end, even
8378 -- if the context and current scope is a loop.
8380 if Nkind (Associated_Node_For_Itype (PtrT))
8381 in N_Subprogram_Specification
8384 Etype (Defining_Unit_Name (Associated_Node_For_Itype (PtrT)))
8386 Owner := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
8388 Make_Full_Type_Declaration (Loc,
8389 Defining_Identifier => Owner,
8391 Make_Access_To_Object_Definition (Loc,
8392 Subtype_Indication =>
8393 New_Occurrence_Of (T, Loc))));
8395 Freeze_Before (N, Owner);
8396 Build_Final_List (N, Owner);
8397 Set_Associated_Final_Chain (PtrT, Associated_Final_Chain (Owner));
8399 -- Ada 2005 (AI-318-02): If the context is a return object
8400 -- declaration, then the anonymous return subtype is defined to have
8401 -- the same accessibility level as that of the function's result
8402 -- subtype, which means that we want the scope where the function is
8405 elsif Nkind (Associated_Node_For_Itype (PtrT)) = N_Object_Declaration
8406 and then Ekind (Scope (PtrT)) = E_Return_Statement
8408 Owner := Scope (Return_Applies_To (Scope (PtrT)));
8410 -- Case of an access discriminant, or (Ada 2005), of an anonymous
8411 -- access component or anonymous access function result: find the
8412 -- final list associated with the scope of the type. (In the
8413 -- anonymous access component kind, a list controller will have
8414 -- been allocated when freezing the record type, and PtrT has an
8415 -- Associated_Final_Chain attribute designating it.)
8417 elsif No (Associated_Final_Chain (PtrT)) then
8418 Owner := Scope (PtrT);
8422 return Find_Final_List (Owner);
8423 end Get_Allocator_Final_List;
8425 ---------------------------------
8426 -- Has_Inferable_Discriminants --
8427 ---------------------------------
8429 function Has_Inferable_Discriminants (N : Node_Id) return Boolean is
8431 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean;
8432 -- Determines whether the left-most prefix of a selected component is a
8433 -- formal parameter in a subprogram. Assumes N is a selected component.
8435 --------------------------------
8436 -- Prefix_Is_Formal_Parameter --
8437 --------------------------------
8439 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean is
8440 Sel_Comp : Node_Id := N;
8443 -- Move to the left-most prefix by climbing up the tree
8445 while Present (Parent (Sel_Comp))
8446 and then Nkind (Parent (Sel_Comp)) = N_Selected_Component
8448 Sel_Comp := Parent (Sel_Comp);
8451 return Ekind (Entity (Prefix (Sel_Comp))) in Formal_Kind;
8452 end Prefix_Is_Formal_Parameter;
8454 -- Start of processing for Has_Inferable_Discriminants
8457 -- For identifiers and indexed components, it is sufficient to have a
8458 -- constrained Unchecked_Union nominal subtype.
8460 if Nkind_In (N, N_Identifier, N_Indexed_Component) then
8461 return Is_Unchecked_Union (Base_Type (Etype (N)))
8463 Is_Constrained (Etype (N));
8465 -- For selected components, the subtype of the selector must be a
8466 -- constrained Unchecked_Union. If the component is subject to a
8467 -- per-object constraint, then the enclosing object must have inferable
8470 elsif Nkind (N) = N_Selected_Component then
8471 if Has_Per_Object_Constraint (Entity (Selector_Name (N))) then
8473 -- A small hack. If we have a per-object constrained selected
8474 -- component of a formal parameter, return True since we do not
8475 -- know the actual parameter association yet.
8477 if Prefix_Is_Formal_Parameter (N) then
8481 -- Otherwise, check the enclosing object and the selector
8483 return Has_Inferable_Discriminants (Prefix (N))
8485 Has_Inferable_Discriminants (Selector_Name (N));
8488 -- The call to Has_Inferable_Discriminants will determine whether
8489 -- the selector has a constrained Unchecked_Union nominal type.
8491 return Has_Inferable_Discriminants (Selector_Name (N));
8493 -- A qualified expression has inferable discriminants if its subtype
8494 -- mark is a constrained Unchecked_Union subtype.
8496 elsif Nkind (N) = N_Qualified_Expression then
8497 return Is_Unchecked_Union (Subtype_Mark (N))
8499 Is_Constrained (Subtype_Mark (N));
8504 end Has_Inferable_Discriminants;
8506 -------------------------------
8507 -- Insert_Dereference_Action --
8508 -------------------------------
8510 procedure Insert_Dereference_Action (N : Node_Id) is
8511 Loc : constant Source_Ptr := Sloc (N);
8512 Typ : constant Entity_Id := Etype (N);
8513 Pool : constant Entity_Id := Associated_Storage_Pool (Typ);
8514 Pnod : constant Node_Id := Parent (N);
8516 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean;
8517 -- Return true if type of P is derived from Checked_Pool;
8519 -----------------------------
8520 -- Is_Checked_Storage_Pool --
8521 -----------------------------
8523 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean is
8532 while T /= Etype (T) loop
8533 if Is_RTE (T, RE_Checked_Pool) then
8541 end Is_Checked_Storage_Pool;
8543 -- Start of processing for Insert_Dereference_Action
8546 pragma Assert (Nkind (Pnod) = N_Explicit_Dereference);
8548 if not (Is_Checked_Storage_Pool (Pool)
8549 and then Comes_From_Source (Original_Node (Pnod)))
8555 Make_Procedure_Call_Statement (Loc,
8556 Name => New_Reference_To (
8557 Find_Prim_Op (Etype (Pool), Name_Dereference), Loc),
8559 Parameter_Associations => New_List (
8563 New_Reference_To (Pool, Loc),
8565 -- Storage_Address. We use the attribute Pool_Address, which uses
8566 -- the pointer itself to find the address of the object, and which
8567 -- handles unconstrained arrays properly by computing the address
8568 -- of the template. i.e. the correct address of the corresponding
8571 Make_Attribute_Reference (Loc,
8572 Prefix => Duplicate_Subexpr_Move_Checks (N),
8573 Attribute_Name => Name_Pool_Address),
8575 -- Size_In_Storage_Elements
8577 Make_Op_Divide (Loc,
8579 Make_Attribute_Reference (Loc,
8581 Make_Explicit_Dereference (Loc,
8582 Duplicate_Subexpr_Move_Checks (N)),
8583 Attribute_Name => Name_Size),
8585 Make_Integer_Literal (Loc, System_Storage_Unit)),
8589 Make_Attribute_Reference (Loc,
8591 Make_Explicit_Dereference (Loc,
8592 Duplicate_Subexpr_Move_Checks (N)),
8593 Attribute_Name => Name_Alignment))));
8596 when RE_Not_Available =>
8598 end Insert_Dereference_Action;
8600 ------------------------------
8601 -- Make_Array_Comparison_Op --
8602 ------------------------------
8604 -- This is a hand-coded expansion of the following generic function:
8607 -- type elem is (<>);
8608 -- type index is (<>);
8609 -- type a is array (index range <>) of elem;
8611 -- function Gnnn (X : a; Y: a) return boolean is
8612 -- J : index := Y'first;
8615 -- if X'length = 0 then
8618 -- elsif Y'length = 0 then
8622 -- for I in X'range loop
8623 -- if X (I) = Y (J) then
8624 -- if J = Y'last then
8627 -- J := index'succ (J);
8631 -- return X (I) > Y (J);
8635 -- return X'length > Y'length;
8639 -- Note that since we are essentially doing this expansion by hand, we
8640 -- do not need to generate an actual or formal generic part, just the
8641 -- instantiated function itself.
8643 function Make_Array_Comparison_Op
8645 Nod : Node_Id) return Node_Id
8647 Loc : constant Source_Ptr := Sloc (Nod);
8649 X : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uX);
8650 Y : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uY);
8651 I : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uI);
8652 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
8654 Index : constant Entity_Id := Base_Type (Etype (First_Index (Typ)));
8656 Loop_Statement : Node_Id;
8657 Loop_Body : Node_Id;
8660 Final_Expr : Node_Id;
8661 Func_Body : Node_Id;
8662 Func_Name : Entity_Id;
8668 -- if J = Y'last then
8671 -- J := index'succ (J);
8675 Make_Implicit_If_Statement (Nod,
8678 Left_Opnd => New_Reference_To (J, Loc),
8680 Make_Attribute_Reference (Loc,
8681 Prefix => New_Reference_To (Y, Loc),
8682 Attribute_Name => Name_Last)),
8684 Then_Statements => New_List (
8685 Make_Exit_Statement (Loc)),
8689 Make_Assignment_Statement (Loc,
8690 Name => New_Reference_To (J, Loc),
8692 Make_Attribute_Reference (Loc,
8693 Prefix => New_Reference_To (Index, Loc),
8694 Attribute_Name => Name_Succ,
8695 Expressions => New_List (New_Reference_To (J, Loc))))));
8697 -- if X (I) = Y (J) then
8700 -- return X (I) > Y (J);
8704 Make_Implicit_If_Statement (Nod,
8708 Make_Indexed_Component (Loc,
8709 Prefix => New_Reference_To (X, Loc),
8710 Expressions => New_List (New_Reference_To (I, Loc))),
8713 Make_Indexed_Component (Loc,
8714 Prefix => New_Reference_To (Y, Loc),
8715 Expressions => New_List (New_Reference_To (J, Loc)))),
8717 Then_Statements => New_List (Inner_If),
8719 Else_Statements => New_List (
8720 Make_Simple_Return_Statement (Loc,
8724 Make_Indexed_Component (Loc,
8725 Prefix => New_Reference_To (X, Loc),
8726 Expressions => New_List (New_Reference_To (I, Loc))),
8729 Make_Indexed_Component (Loc,
8730 Prefix => New_Reference_To (Y, Loc),
8731 Expressions => New_List (
8732 New_Reference_To (J, Loc)))))));
8734 -- for I in X'range loop
8739 Make_Implicit_Loop_Statement (Nod,
8740 Identifier => Empty,
8743 Make_Iteration_Scheme (Loc,
8744 Loop_Parameter_Specification =>
8745 Make_Loop_Parameter_Specification (Loc,
8746 Defining_Identifier => I,
8747 Discrete_Subtype_Definition =>
8748 Make_Attribute_Reference (Loc,
8749 Prefix => New_Reference_To (X, Loc),
8750 Attribute_Name => Name_Range))),
8752 Statements => New_List (Loop_Body));
8754 -- if X'length = 0 then
8756 -- elsif Y'length = 0 then
8759 -- for ... loop ... end loop;
8760 -- return X'length > Y'length;
8764 Make_Attribute_Reference (Loc,
8765 Prefix => New_Reference_To (X, Loc),
8766 Attribute_Name => Name_Length);
8769 Make_Attribute_Reference (Loc,
8770 Prefix => New_Reference_To (Y, Loc),
8771 Attribute_Name => Name_Length);
8775 Left_Opnd => Length1,
8776 Right_Opnd => Length2);
8779 Make_Implicit_If_Statement (Nod,
8783 Make_Attribute_Reference (Loc,
8784 Prefix => New_Reference_To (X, Loc),
8785 Attribute_Name => Name_Length),
8787 Make_Integer_Literal (Loc, 0)),
8791 Make_Simple_Return_Statement (Loc,
8792 Expression => New_Reference_To (Standard_False, Loc))),
8794 Elsif_Parts => New_List (
8795 Make_Elsif_Part (Loc,
8799 Make_Attribute_Reference (Loc,
8800 Prefix => New_Reference_To (Y, Loc),
8801 Attribute_Name => Name_Length),
8803 Make_Integer_Literal (Loc, 0)),
8807 Make_Simple_Return_Statement (Loc,
8808 Expression => New_Reference_To (Standard_True, Loc))))),
8810 Else_Statements => New_List (
8812 Make_Simple_Return_Statement (Loc,
8813 Expression => Final_Expr)));
8817 Formals := New_List (
8818 Make_Parameter_Specification (Loc,
8819 Defining_Identifier => X,
8820 Parameter_Type => New_Reference_To (Typ, Loc)),
8822 Make_Parameter_Specification (Loc,
8823 Defining_Identifier => Y,
8824 Parameter_Type => New_Reference_To (Typ, Loc)));
8826 -- function Gnnn (...) return boolean is
8827 -- J : index := Y'first;
8832 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
8835 Make_Subprogram_Body (Loc,
8837 Make_Function_Specification (Loc,
8838 Defining_Unit_Name => Func_Name,
8839 Parameter_Specifications => Formals,
8840 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
8842 Declarations => New_List (
8843 Make_Object_Declaration (Loc,
8844 Defining_Identifier => J,
8845 Object_Definition => New_Reference_To (Index, Loc),
8847 Make_Attribute_Reference (Loc,
8848 Prefix => New_Reference_To (Y, Loc),
8849 Attribute_Name => Name_First))),
8851 Handled_Statement_Sequence =>
8852 Make_Handled_Sequence_Of_Statements (Loc,
8853 Statements => New_List (If_Stat)));
8856 end Make_Array_Comparison_Op;
8858 ---------------------------
8859 -- Make_Boolean_Array_Op --
8860 ---------------------------
8862 -- For logical operations on boolean arrays, expand in line the following,
8863 -- replacing 'and' with 'or' or 'xor' where needed:
8865 -- function Annn (A : typ; B: typ) return typ is
8868 -- for J in A'range loop
8869 -- C (J) := A (J) op B (J);
8874 -- Here typ is the boolean array type
8876 function Make_Boolean_Array_Op
8878 N : Node_Id) return Node_Id
8880 Loc : constant Source_Ptr := Sloc (N);
8882 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
8883 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
8884 C : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uC);
8885 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
8893 Func_Name : Entity_Id;
8894 Func_Body : Node_Id;
8895 Loop_Statement : Node_Id;
8899 Make_Indexed_Component (Loc,
8900 Prefix => New_Reference_To (A, Loc),
8901 Expressions => New_List (New_Reference_To (J, Loc)));
8904 Make_Indexed_Component (Loc,
8905 Prefix => New_Reference_To (B, Loc),
8906 Expressions => New_List (New_Reference_To (J, Loc)));
8909 Make_Indexed_Component (Loc,
8910 Prefix => New_Reference_To (C, Loc),
8911 Expressions => New_List (New_Reference_To (J, Loc)));
8913 if Nkind (N) = N_Op_And then
8919 elsif Nkind (N) = N_Op_Or then
8933 Make_Implicit_Loop_Statement (N,
8934 Identifier => Empty,
8937 Make_Iteration_Scheme (Loc,
8938 Loop_Parameter_Specification =>
8939 Make_Loop_Parameter_Specification (Loc,
8940 Defining_Identifier => J,
8941 Discrete_Subtype_Definition =>
8942 Make_Attribute_Reference (Loc,
8943 Prefix => New_Reference_To (A, Loc),
8944 Attribute_Name => Name_Range))),
8946 Statements => New_List (
8947 Make_Assignment_Statement (Loc,
8949 Expression => Op)));
8951 Formals := New_List (
8952 Make_Parameter_Specification (Loc,
8953 Defining_Identifier => A,
8954 Parameter_Type => New_Reference_To (Typ, Loc)),
8956 Make_Parameter_Specification (Loc,
8957 Defining_Identifier => B,
8958 Parameter_Type => New_Reference_To (Typ, Loc)));
8961 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
8962 Set_Is_Inlined (Func_Name);
8965 Make_Subprogram_Body (Loc,
8967 Make_Function_Specification (Loc,
8968 Defining_Unit_Name => Func_Name,
8969 Parameter_Specifications => Formals,
8970 Result_Definition => New_Reference_To (Typ, Loc)),
8972 Declarations => New_List (
8973 Make_Object_Declaration (Loc,
8974 Defining_Identifier => C,
8975 Object_Definition => New_Reference_To (Typ, Loc))),
8977 Handled_Statement_Sequence =>
8978 Make_Handled_Sequence_Of_Statements (Loc,
8979 Statements => New_List (
8981 Make_Simple_Return_Statement (Loc,
8982 Expression => New_Reference_To (C, Loc)))));
8985 end Make_Boolean_Array_Op;
8987 ------------------------
8988 -- Rewrite_Comparison --
8989 ------------------------
8991 procedure Rewrite_Comparison (N : Node_Id) is
8992 Warning_Generated : Boolean := False;
8993 -- Set to True if first pass with Assume_Valid generates a warning in
8994 -- which case we skip the second pass to avoid warning overloaded.
8997 -- Set to Standard_True or Standard_False
9000 if Nkind (N) = N_Type_Conversion then
9001 Rewrite_Comparison (Expression (N));
9004 elsif Nkind (N) not in N_Op_Compare then
9008 -- Now start looking at the comparison in detail. We potentially go
9009 -- through this loop twice. The first time, Assume_Valid is set False
9010 -- in the call to Compile_Time_Compare. If this call results in a
9011 -- clear result of always True or Always False, that's decisive and
9012 -- we are done. Otherwise we repeat the processing with Assume_Valid
9013 -- set to True to generate additional warnings. We can stil that step
9014 -- if Constant_Condition_Warnings is False.
9016 for AV in False .. True loop
9018 Typ : constant Entity_Id := Etype (N);
9019 Op1 : constant Node_Id := Left_Opnd (N);
9020 Op2 : constant Node_Id := Right_Opnd (N);
9022 Res : constant Compare_Result :=
9023 Compile_Time_Compare (Op1, Op2, Assume_Valid => AV);
9024 -- Res indicates if compare outcome can be compile time determined
9026 True_Result : Boolean;
9027 False_Result : Boolean;
9030 case N_Op_Compare (Nkind (N)) is
9032 True_Result := Res = EQ;
9033 False_Result := Res = LT or else Res = GT or else Res = NE;
9036 True_Result := Res in Compare_GE;
9037 False_Result := Res = LT;
9040 and then Constant_Condition_Warnings
9041 and then Comes_From_Source (Original_Node (N))
9042 and then Nkind (Original_Node (N)) = N_Op_Ge
9043 and then not In_Instance
9044 and then Is_Integer_Type (Etype (Left_Opnd (N)))
9045 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
9048 ("can never be greater than, could replace by ""'=""?", N);
9049 Warning_Generated := True;
9053 True_Result := Res = GT;
9054 False_Result := Res in Compare_LE;
9057 True_Result := Res = LT;
9058 False_Result := Res in Compare_GE;
9061 True_Result := Res in Compare_LE;
9062 False_Result := Res = GT;
9065 and then Constant_Condition_Warnings
9066 and then Comes_From_Source (Original_Node (N))
9067 and then Nkind (Original_Node (N)) = N_Op_Le
9068 and then not In_Instance
9069 and then Is_Integer_Type (Etype (Left_Opnd (N)))
9070 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
9073 ("can never be less than, could replace by ""'=""?", N);
9074 Warning_Generated := True;
9078 True_Result := Res = NE or else Res = GT or else Res = LT;
9079 False_Result := Res = EQ;
9082 -- If this is the first iteration, then we actually convert the
9083 -- comparison into True or False, if the result is certain.
9086 if True_Result or False_Result then
9088 Result := Standard_True;
9090 Result := Standard_False;
9095 New_Occurrence_Of (Result, Sloc (N))));
9096 Analyze_And_Resolve (N, Typ);
9097 Warn_On_Known_Condition (N);
9101 -- If this is the second iteration (AV = True), and the original
9102 -- node comes from source and we are not in an instance, then
9103 -- give a warning if we know result would be True or False. Note
9104 -- we know Constant_Condition_Warnings is set if we get here.
9106 elsif Comes_From_Source (Original_Node (N))
9107 and then not In_Instance
9111 ("condition can only be False if invalid values present?",
9113 elsif False_Result then
9115 ("condition can only be True if invalid values present?",
9121 -- Skip second iteration if not warning on constant conditions or
9122 -- if the first iteration already generated a warning of some kind
9123 -- or if we are in any case assuming all values are valid (so that
9124 -- the first iteration took care of the valid case).
9126 exit when not Constant_Condition_Warnings;
9127 exit when Warning_Generated;
9128 exit when Assume_No_Invalid_Values;
9130 end Rewrite_Comparison;
9132 ----------------------------
9133 -- Safe_In_Place_Array_Op --
9134 ----------------------------
9136 function Safe_In_Place_Array_Op
9139 Op2 : Node_Id) return Boolean
9143 function Is_Safe_Operand (Op : Node_Id) return Boolean;
9144 -- Operand is safe if it cannot overlap part of the target of the
9145 -- operation. If the operand and the target are identical, the operand
9146 -- is safe. The operand can be empty in the case of negation.
9148 function Is_Unaliased (N : Node_Id) return Boolean;
9149 -- Check that N is a stand-alone entity
9155 function Is_Unaliased (N : Node_Id) return Boolean is
9159 and then No (Address_Clause (Entity (N)))
9160 and then No (Renamed_Object (Entity (N)));
9163 ---------------------
9164 -- Is_Safe_Operand --
9165 ---------------------
9167 function Is_Safe_Operand (Op : Node_Id) return Boolean is
9172 elsif Is_Entity_Name (Op) then
9173 return Is_Unaliased (Op);
9175 elsif Nkind_In (Op, N_Indexed_Component, N_Selected_Component) then
9176 return Is_Unaliased (Prefix (Op));
9178 elsif Nkind (Op) = N_Slice then
9180 Is_Unaliased (Prefix (Op))
9181 and then Entity (Prefix (Op)) /= Target;
9183 elsif Nkind (Op) = N_Op_Not then
9184 return Is_Safe_Operand (Right_Opnd (Op));
9189 end Is_Safe_Operand;
9191 -- Start of processing for Is_Safe_In_Place_Array_Op
9194 -- Skip this processing if the component size is different from system
9195 -- storage unit (since at least for NOT this would cause problems).
9197 if Component_Size (Etype (Lhs)) /= System_Storage_Unit then
9200 -- Cannot do in place stuff on VM_Target since cannot pass addresses
9202 elsif VM_Target /= No_VM then
9205 -- Cannot do in place stuff if non-standard Boolean representation
9207 elsif Has_Non_Standard_Rep (Component_Type (Etype (Lhs))) then
9210 elsif not Is_Unaliased (Lhs) then
9213 Target := Entity (Lhs);
9216 Is_Safe_Operand (Op1)
9217 and then Is_Safe_Operand (Op2);
9219 end Safe_In_Place_Array_Op;
9221 -----------------------
9222 -- Tagged_Membership --
9223 -----------------------
9225 -- There are two different cases to consider depending on whether the right
9226 -- operand is a class-wide type or not. If not we just compare the actual
9227 -- tag of the left expr to the target type tag:
9229 -- Left_Expr.Tag = Right_Type'Tag;
9231 -- If it is a class-wide type we use the RT function CW_Membership which is
9232 -- usually implemented by looking in the ancestor tables contained in the
9233 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
9235 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
9236 -- function IW_Membership which is usually implemented by looking in the
9237 -- table of abstract interface types plus the ancestor table contained in
9238 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
9240 function Tagged_Membership (N : Node_Id) return Node_Id is
9241 Left : constant Node_Id := Left_Opnd (N);
9242 Right : constant Node_Id := Right_Opnd (N);
9243 Loc : constant Source_Ptr := Sloc (N);
9245 Left_Type : Entity_Id;
9246 Right_Type : Entity_Id;
9250 Left_Type := Etype (Left);
9251 Right_Type := Etype (Right);
9253 if Is_Class_Wide_Type (Left_Type) then
9254 Left_Type := Root_Type (Left_Type);
9258 Make_Selected_Component (Loc,
9259 Prefix => Relocate_Node (Left),
9261 New_Reference_To (First_Tag_Component (Left_Type), Loc));
9263 if Is_Class_Wide_Type (Right_Type) then
9265 -- No need to issue a run-time check if we statically know that the
9266 -- result of this membership test is always true. For example,
9267 -- considering the following declarations:
9269 -- type Iface is interface;
9270 -- type T is tagged null record;
9271 -- type DT is new T and Iface with null record;
9276 -- These membership tests are always true:
9280 -- Obj2 in Iface'Class;
9282 -- We do not need to handle cases where the membership is illegal.
9285 -- Obj1 in DT'Class; -- Compile time error
9286 -- Obj1 in Iface'Class; -- Compile time error
9288 if not Is_Class_Wide_Type (Left_Type)
9289 and then (Is_Ancestor (Etype (Right_Type), Left_Type)
9290 or else (Is_Interface (Etype (Right_Type))
9291 and then Interface_Present_In_Ancestor
9293 Iface => Etype (Right_Type))))
9295 return New_Reference_To (Standard_True, Loc);
9298 -- Ada 2005 (AI-251): Class-wide applied to interfaces
9300 if Is_Interface (Etype (Class_Wide_Type (Right_Type)))
9302 -- Support to: "Iface_CW_Typ in Typ'Class"
9304 or else Is_Interface (Left_Type)
9306 -- Issue error if IW_Membership operation not available in a
9307 -- configurable run time setting.
9309 if not RTE_Available (RE_IW_Membership) then
9311 ("dynamic membership test on interface types", N);
9316 Make_Function_Call (Loc,
9317 Name => New_Occurrence_Of (RTE (RE_IW_Membership), Loc),
9318 Parameter_Associations => New_List (
9319 Make_Attribute_Reference (Loc,
9321 Attribute_Name => Name_Address),
9324 (Access_Disp_Table (Root_Type (Right_Type)))),
9327 -- Ada 95: Normal case
9331 Build_CW_Membership (Loc,
9332 Obj_Tag_Node => Obj_Tag,
9336 (Access_Disp_Table (Root_Type (Right_Type)))),
9340 -- Right_Type is not a class-wide type
9343 -- No need to check the tag of the object if Right_Typ is abstract
9345 if Is_Abstract_Type (Right_Type) then
9346 return New_Reference_To (Standard_False, Loc);
9351 Left_Opnd => Obj_Tag,
9354 (Node (First_Elmt (Access_Disp_Table (Right_Type))), Loc));
9357 end Tagged_Membership;
9359 ------------------------------
9360 -- Unary_Op_Validity_Checks --
9361 ------------------------------
9363 procedure Unary_Op_Validity_Checks (N : Node_Id) is
9365 if Validity_Checks_On and Validity_Check_Operands then
9366 Ensure_Valid (Right_Opnd (N));
9368 end Unary_Op_Validity_Checks;
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