1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Aggr; use Exp_Aggr;
33 with Exp_Atag; use Exp_Atag;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch6; use Exp_Ch6;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Disp; use Exp_Disp;
39 with Exp_Fixd; use Exp_Fixd;
40 with Exp_Pakd; use Exp_Pakd;
41 with Exp_Tss; use Exp_Tss;
42 with Exp_Util; use Exp_Util;
43 with Exp_VFpt; use Exp_VFpt;
44 with Freeze; use Freeze;
45 with Inline; use Inline;
46 with Namet; use Namet;
47 with Nlists; use Nlists;
48 with Nmake; use Nmake;
50 with Restrict; use Restrict;
51 with Rident; use Rident;
52 with Rtsfind; use Rtsfind;
54 with Sem_Aux; use Sem_Aux;
55 with Sem_Cat; use Sem_Cat;
56 with Sem_Ch3; use Sem_Ch3;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch13; use Sem_Ch13;
59 with Sem_Eval; use Sem_Eval;
60 with Sem_Res; use Sem_Res;
61 with Sem_SCIL; use Sem_SCIL;
62 with Sem_Type; use Sem_Type;
63 with Sem_Util; use Sem_Util;
64 with Sem_Warn; use Sem_Warn;
65 with Sinfo; use Sinfo;
66 with Snames; use Snames;
67 with Stand; use Stand;
68 with Targparm; use Targparm;
69 with Tbuild; use Tbuild;
70 with Ttypes; use Ttypes;
71 with Uintp; use Uintp;
72 with Urealp; use Urealp;
73 with Validsw; use Validsw;
75 package body Exp_Ch4 is
77 -----------------------
78 -- Local Subprograms --
79 -----------------------
81 procedure Binary_Op_Validity_Checks (N : Node_Id);
82 pragma Inline (Binary_Op_Validity_Checks);
83 -- Performs validity checks for a binary operator
85 procedure Build_Boolean_Array_Proc_Call
89 -- If a boolean array assignment can be done in place, build call to
90 -- corresponding library procedure.
92 procedure Displace_Allocator_Pointer (N : Node_Id);
93 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
94 -- Expand_Allocator_Expression. Allocating class-wide interface objects
95 -- this routine displaces the pointer to the allocated object to reference
96 -- the component referencing the corresponding secondary dispatch table.
98 procedure Expand_Allocator_Expression (N : Node_Id);
99 -- Subsidiary to Expand_N_Allocator, for the case when the expression
100 -- is a qualified expression or an aggregate.
102 procedure Expand_Array_Comparison (N : Node_Id);
103 -- This routine handles expansion of the comparison operators (N_Op_Lt,
104 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
105 -- code for these operators is similar, differing only in the details of
106 -- the actual comparison call that is made. Special processing (call a
109 function Expand_Array_Equality
114 Typ : Entity_Id) return Node_Id;
115 -- Expand an array equality into a call to a function implementing this
116 -- equality, and a call to it. Loc is the location for the generated nodes.
117 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
118 -- on which to attach bodies of local functions that are created in the
119 -- process. It is the responsibility of the caller to insert those bodies
120 -- at the right place. Nod provides the Sloc value for the generated code.
121 -- Normally the types used for the generated equality routine are taken
122 -- from Lhs and Rhs. However, in some situations of generated code, the
123 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
124 -- the type to be used for the formal parameters.
126 procedure Expand_Boolean_Operator (N : Node_Id);
127 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
128 -- case of array type arguments.
130 function Expand_Composite_Equality
135 Bodies : List_Id) return Node_Id;
136 -- Local recursive function used to expand equality for nested composite
137 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
138 -- to attach bodies of local functions that are created in the process.
139 -- This is the responsibility of the caller to insert those bodies at the
140 -- right place. Nod provides the Sloc value for generated code. Lhs and Rhs
141 -- are the left and right sides for the comparison, and Typ is the type of
142 -- the arrays to compare.
144 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id);
145 -- Routine to expand concatenation of a sequence of two or more operands
146 -- (in the list Operands) and replace node Cnode with the result of the
147 -- concatenation. The operands can be of any appropriate type, and can
148 -- include both arrays and singleton elements.
150 procedure Fixup_Universal_Fixed_Operation (N : Node_Id);
151 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
152 -- fixed. We do not have such a type at runtime, so the purpose of this
153 -- routine is to find the real type by looking up the tree. We also
154 -- determine if the operation must be rounded.
156 function Get_Allocator_Final_List
159 PtrT : Entity_Id) return Entity_Id;
160 -- If the designated type is controlled, build final_list expression for
161 -- created object. If context is an access parameter, create a local access
162 -- type to have a usable finalization list.
164 function Has_Inferable_Discriminants (N : Node_Id) return Boolean;
165 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
166 -- discriminants if it has a constrained nominal type, unless the object
167 -- is a component of an enclosing Unchecked_Union object that is subject
168 -- to a per-object constraint and the enclosing object lacks inferable
171 -- An expression of an Unchecked_Union type has inferable discriminants
172 -- if it is either a name of an object with inferable discriminants or a
173 -- qualified expression whose subtype mark denotes a constrained subtype.
175 procedure Insert_Dereference_Action (N : Node_Id);
176 -- N is an expression whose type is an access. When the type of the
177 -- associated storage pool is derived from Checked_Pool, generate a
178 -- call to the 'Dereference' primitive operation.
180 function Make_Array_Comparison_Op
182 Nod : Node_Id) return Node_Id;
183 -- Comparisons between arrays are expanded in line. This function produces
184 -- the body of the implementation of (a > b), where a and b are one-
185 -- dimensional arrays of some discrete type. The original node is then
186 -- expanded into the appropriate call to this function. Nod provides the
187 -- Sloc value for the generated code.
189 function Make_Boolean_Array_Op
191 N : Node_Id) return Node_Id;
192 -- Boolean operations on boolean arrays are expanded in line. This function
193 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
194 -- b). It is used only the normal case and not the packed case. The type
195 -- involved, Typ, is the Boolean array type, and the logical operations in
196 -- the body are simple boolean operations. Note that Typ is always a
197 -- constrained type (the caller has ensured this by using
198 -- Convert_To_Actual_Subtype if necessary).
200 procedure Rewrite_Comparison (N : Node_Id);
201 -- If N is the node for a comparison whose outcome can be determined at
202 -- compile time, then the node N can be rewritten with True or False. If
203 -- the outcome cannot be determined at compile time, the call has no
204 -- effect. If N is a type conversion, then this processing is applied to
205 -- its expression. If N is neither comparison nor a type conversion, the
206 -- call has no effect.
208 function Tagged_Membership (N : Node_Id) return Node_Id;
209 -- Construct the expression corresponding to the tagged membership test.
210 -- Deals with a second operand being (or not) a class-wide type.
212 function Safe_In_Place_Array_Op
215 Op2 : Node_Id) return Boolean;
216 -- In the context of an assignment, where the right-hand side is a boolean
217 -- operation on arrays, check whether operation can be performed in place.
219 procedure Unary_Op_Validity_Checks (N : Node_Id);
220 pragma Inline (Unary_Op_Validity_Checks);
221 -- Performs validity checks for a unary operator
223 -------------------------------
224 -- Binary_Op_Validity_Checks --
225 -------------------------------
227 procedure Binary_Op_Validity_Checks (N : Node_Id) is
229 if Validity_Checks_On and Validity_Check_Operands then
230 Ensure_Valid (Left_Opnd (N));
231 Ensure_Valid (Right_Opnd (N));
233 end Binary_Op_Validity_Checks;
235 ------------------------------------
236 -- Build_Boolean_Array_Proc_Call --
237 ------------------------------------
239 procedure Build_Boolean_Array_Proc_Call
244 Loc : constant Source_Ptr := Sloc (N);
245 Kind : constant Node_Kind := Nkind (Expression (N));
246 Target : constant Node_Id :=
247 Make_Attribute_Reference (Loc,
249 Attribute_Name => Name_Address);
251 Arg1 : constant Node_Id := Op1;
252 Arg2 : Node_Id := Op2;
254 Proc_Name : Entity_Id;
257 if Kind = N_Op_Not then
258 if Nkind (Op1) in N_Binary_Op then
260 -- Use negated version of the binary operators
262 if Nkind (Op1) = N_Op_And then
263 Proc_Name := RTE (RE_Vector_Nand);
265 elsif Nkind (Op1) = N_Op_Or then
266 Proc_Name := RTE (RE_Vector_Nor);
268 else pragma Assert (Nkind (Op1) = N_Op_Xor);
269 Proc_Name := RTE (RE_Vector_Xor);
273 Make_Procedure_Call_Statement (Loc,
274 Name => New_Occurrence_Of (Proc_Name, Loc),
276 Parameter_Associations => New_List (
278 Make_Attribute_Reference (Loc,
279 Prefix => Left_Opnd (Op1),
280 Attribute_Name => Name_Address),
282 Make_Attribute_Reference (Loc,
283 Prefix => Right_Opnd (Op1),
284 Attribute_Name => Name_Address),
286 Make_Attribute_Reference (Loc,
287 Prefix => Left_Opnd (Op1),
288 Attribute_Name => Name_Length)));
291 Proc_Name := RTE (RE_Vector_Not);
294 Make_Procedure_Call_Statement (Loc,
295 Name => New_Occurrence_Of (Proc_Name, Loc),
296 Parameter_Associations => New_List (
299 Make_Attribute_Reference (Loc,
301 Attribute_Name => Name_Address),
303 Make_Attribute_Reference (Loc,
305 Attribute_Name => Name_Length)));
309 -- We use the following equivalences:
311 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
312 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
313 -- (not X) xor (not Y) = X xor Y
314 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
316 if Nkind (Op1) = N_Op_Not then
317 if Kind = N_Op_And then
318 Proc_Name := RTE (RE_Vector_Nor);
320 elsif Kind = N_Op_Or then
321 Proc_Name := RTE (RE_Vector_Nand);
324 Proc_Name := RTE (RE_Vector_Xor);
328 if Kind = N_Op_And then
329 Proc_Name := RTE (RE_Vector_And);
331 elsif Kind = N_Op_Or then
332 Proc_Name := RTE (RE_Vector_Or);
334 elsif Nkind (Op2) = N_Op_Not then
335 Proc_Name := RTE (RE_Vector_Nxor);
336 Arg2 := Right_Opnd (Op2);
339 Proc_Name := RTE (RE_Vector_Xor);
344 Make_Procedure_Call_Statement (Loc,
345 Name => New_Occurrence_Of (Proc_Name, Loc),
346 Parameter_Associations => New_List (
348 Make_Attribute_Reference (Loc,
350 Attribute_Name => Name_Address),
351 Make_Attribute_Reference (Loc,
353 Attribute_Name => Name_Address),
354 Make_Attribute_Reference (Loc,
356 Attribute_Name => Name_Length)));
359 Rewrite (N, Call_Node);
363 when RE_Not_Available =>
365 end Build_Boolean_Array_Proc_Call;
367 --------------------------------
368 -- Displace_Allocator_Pointer --
369 --------------------------------
371 procedure Displace_Allocator_Pointer (N : Node_Id) is
372 Loc : constant Source_Ptr := Sloc (N);
373 Orig_Node : constant Node_Id := Original_Node (N);
379 -- Do nothing in case of VM targets: the virtual machine will handle
380 -- interfaces directly.
382 if not Tagged_Type_Expansion then
386 pragma Assert (Nkind (N) = N_Identifier
387 and then Nkind (Orig_Node) = N_Allocator);
389 PtrT := Etype (Orig_Node);
390 Dtyp := Available_View (Designated_Type (PtrT));
391 Etyp := Etype (Expression (Orig_Node));
393 if Is_Class_Wide_Type (Dtyp)
394 and then Is_Interface (Dtyp)
396 -- If the type of the allocator expression is not an interface type
397 -- we can generate code to reference the record component containing
398 -- the pointer to the secondary dispatch table.
400 if not Is_Interface (Etyp) then
402 Saved_Typ : constant Entity_Id := Etype (Orig_Node);
405 -- 1) Get access to the allocated object
408 Make_Explicit_Dereference (Loc,
413 -- 2) Add the conversion to displace the pointer to reference
414 -- the secondary dispatch table.
416 Rewrite (N, Convert_To (Dtyp, Relocate_Node (N)));
417 Analyze_And_Resolve (N, Dtyp);
419 -- 3) The 'access to the secondary dispatch table will be used
420 -- as the value returned by the allocator.
423 Make_Attribute_Reference (Loc,
424 Prefix => Relocate_Node (N),
425 Attribute_Name => Name_Access));
426 Set_Etype (N, Saved_Typ);
430 -- If the type of the allocator expression is an interface type we
431 -- generate a run-time call to displace "this" to reference the
432 -- component containing the pointer to the secondary dispatch table
433 -- or else raise Constraint_Error if the actual object does not
434 -- implement the target interface. This case corresponds with the
435 -- following example:
437 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
439 -- return new Iface_2'Class'(Obj);
444 Unchecked_Convert_To (PtrT,
445 Make_Function_Call (Loc,
446 Name => New_Reference_To (RTE (RE_Displace), Loc),
447 Parameter_Associations => New_List (
448 Unchecked_Convert_To (RTE (RE_Address),
454 (Access_Disp_Table (Etype (Base_Type (Dtyp))))),
456 Analyze_And_Resolve (N, PtrT);
459 end Displace_Allocator_Pointer;
461 ---------------------------------
462 -- Expand_Allocator_Expression --
463 ---------------------------------
465 procedure Expand_Allocator_Expression (N : Node_Id) is
466 Loc : constant Source_Ptr := Sloc (N);
467 Exp : constant Node_Id := Expression (Expression (N));
468 PtrT : constant Entity_Id := Etype (N);
469 DesigT : constant Entity_Id := Designated_Type (PtrT);
471 procedure Apply_Accessibility_Check
473 Built_In_Place : Boolean := False);
474 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
475 -- type, generate an accessibility check to verify that the level of the
476 -- type of the created object is not deeper than the level of the access
477 -- type. If the type of the qualified expression is class- wide, then
478 -- always generate the check (except in the case where it is known to be
479 -- unnecessary, see comment below). Otherwise, only generate the check
480 -- if the level of the qualified expression type is statically deeper
481 -- than the access type.
483 -- Although the static accessibility will generally have been performed
484 -- as a legality check, it won't have been done in cases where the
485 -- allocator appears in generic body, so a run-time check is needed in
486 -- general. One special case is when the access type is declared in the
487 -- same scope as the class-wide allocator, in which case the check can
488 -- never fail, so it need not be generated.
490 -- As an open issue, there seem to be cases where the static level
491 -- associated with the class-wide object's underlying type is not
492 -- sufficient to perform the proper accessibility check, such as for
493 -- allocators in nested subprograms or accept statements initialized by
494 -- class-wide formals when the actual originates outside at a deeper
495 -- static level. The nested subprogram case might require passing
496 -- accessibility levels along with class-wide parameters, and the task
497 -- case seems to be an actual gap in the language rules that needs to
498 -- be fixed by the ARG. ???
500 -------------------------------
501 -- Apply_Accessibility_Check --
502 -------------------------------
504 procedure Apply_Accessibility_Check
506 Built_In_Place : Boolean := False)
511 -- Note: we skip the accessibility check for the VM case, since
512 -- there does not seem to be any practical way of implementing it.
514 if Ada_Version >= Ada_05
515 and then Tagged_Type_Expansion
516 and then Is_Class_Wide_Type (DesigT)
517 and then not Scope_Suppress (Accessibility_Check)
519 (Type_Access_Level (Etype (Exp)) > Type_Access_Level (PtrT)
521 (Is_Class_Wide_Type (Etype (Exp))
522 and then Scope (PtrT) /= Current_Scope))
524 -- If the allocator was built in place Ref is already a reference
525 -- to the access object initialized to the result of the allocator
526 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). Otherwise
527 -- it is the entity associated with the object containing the
528 -- address of the allocated object.
530 if Built_In_Place then
531 Ref_Node := New_Copy (Ref);
533 Ref_Node := New_Reference_To (Ref, Loc);
537 Make_Raise_Program_Error (Loc,
541 Build_Get_Access_Level (Loc,
542 Make_Attribute_Reference (Loc,
544 Attribute_Name => Name_Tag)),
546 Make_Integer_Literal (Loc,
547 Type_Access_Level (PtrT))),
548 Reason => PE_Accessibility_Check_Failed));
550 end Apply_Accessibility_Check;
554 Indic : constant Node_Id := Subtype_Mark (Expression (N));
555 T : constant Entity_Id := Entity (Indic);
560 TagT : Entity_Id := Empty;
561 -- Type used as source for tag assignment
563 TagR : Node_Id := Empty;
564 -- Target reference for tag assignment
566 Aggr_In_Place : constant Boolean := Is_Delayed_Aggregate (Exp);
568 Tag_Assign : Node_Id;
571 -- Start of processing for Expand_Allocator_Expression
574 if Is_Tagged_Type (T) or else Needs_Finalization (T) then
576 if Is_CPP_Constructor_Call (Exp) then
579 -- Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn
581 -- Allocate the object with no expression
583 Node := Relocate_Node (N);
584 Set_Expression (Node, New_Reference_To (Etype (Exp), Loc));
586 -- Avoid its expansion to avoid generating a call to the default
591 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
594 Make_Object_Declaration (Loc,
595 Defining_Identifier => Temp,
596 Constant_Present => True,
597 Object_Definition => New_Reference_To (PtrT, Loc),
598 Expression => Node));
600 Apply_Accessibility_Check (Temp);
602 -- Locate the enclosing list and insert the C++ constructor call
609 while not Is_List_Member (P) loop
613 Insert_List_After_And_Analyze (P,
614 Build_Initialization_Call (Loc,
616 Make_Explicit_Dereference (Loc,
617 Prefix => New_Reference_To (Temp, Loc)),
619 Constructor_Ref => Exp));
622 Rewrite (N, New_Reference_To (Temp, Loc));
623 Analyze_And_Resolve (N, PtrT);
627 -- Ada 2005 (AI-318-02): If the initialization expression is a call
628 -- to a build-in-place function, then access to the allocated object
629 -- must be passed to the function. Currently we limit such functions
630 -- to those with constrained limited result subtypes, but eventually
631 -- we plan to expand the allowed forms of functions that are treated
632 -- as build-in-place.
634 if Ada_Version >= Ada_05
635 and then Is_Build_In_Place_Function_Call (Exp)
637 Make_Build_In_Place_Call_In_Allocator (N, Exp);
638 Apply_Accessibility_Check (N, Built_In_Place => True);
642 -- Actions inserted before:
643 -- Temp : constant ptr_T := new T'(Expression);
644 -- <no CW> Temp._tag := T'tag;
645 -- <CTRL> Adjust (Finalizable (Temp.all));
646 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
648 -- We analyze by hand the new internal allocator to avoid
649 -- any recursion and inappropriate call to Initialize
651 -- We don't want to remove side effects when the expression must be
652 -- built in place. In the case of a build-in-place function call,
653 -- that could lead to a duplication of the call, which was already
654 -- substituted for the allocator.
656 if not Aggr_In_Place then
657 Remove_Side_Effects (Exp);
661 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
663 -- For a class wide allocation generate the following code:
665 -- type Equiv_Record is record ... end record;
666 -- implicit subtype CW is <Class_Wide_Subytpe>;
667 -- temp : PtrT := new CW'(CW!(expr));
669 if Is_Class_Wide_Type (T) then
670 Expand_Subtype_From_Expr (Empty, T, Indic, Exp);
672 -- Ada 2005 (AI-251): If the expression is a class-wide interface
673 -- object we generate code to move up "this" to reference the
674 -- base of the object before allocating the new object.
676 -- Note that Exp'Address is recursively expanded into a call
677 -- to Base_Address (Exp.Tag)
679 if Is_Class_Wide_Type (Etype (Exp))
680 and then Is_Interface (Etype (Exp))
681 and then Tagged_Type_Expansion
685 Unchecked_Convert_To (Entity (Indic),
686 Make_Explicit_Dereference (Loc,
687 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
688 Make_Attribute_Reference (Loc,
690 Attribute_Name => Name_Address)))));
695 Unchecked_Convert_To (Entity (Indic), Exp));
698 Analyze_And_Resolve (Expression (N), Entity (Indic));
701 -- Keep separate the management of allocators returning interfaces
703 if not Is_Interface (Directly_Designated_Type (PtrT)) then
704 if Aggr_In_Place then
706 Make_Object_Declaration (Loc,
707 Defining_Identifier => Temp,
708 Object_Definition => New_Reference_To (PtrT, Loc),
711 New_Reference_To (Etype (Exp), Loc)));
713 -- Copy the Comes_From_Source flag for the allocator we just
714 -- built, since logically this allocator is a replacement of
715 -- the original allocator node. This is for proper handling of
716 -- restriction No_Implicit_Heap_Allocations.
718 Set_Comes_From_Source
719 (Expression (Tmp_Node), Comes_From_Source (N));
721 Set_No_Initialization (Expression (Tmp_Node));
722 Insert_Action (N, Tmp_Node);
724 if Needs_Finalization (T)
725 and then Ekind (PtrT) = E_Anonymous_Access_Type
727 -- Create local finalization list for access parameter
729 Flist := Get_Allocator_Final_List (N, Base_Type (T), PtrT);
732 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
735 Node := Relocate_Node (N);
738 Make_Object_Declaration (Loc,
739 Defining_Identifier => Temp,
740 Constant_Present => True,
741 Object_Definition => New_Reference_To (PtrT, Loc),
742 Expression => Node));
745 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
746 -- interface type. In this case we use the type of the qualified
747 -- expression to allocate the object.
751 Def_Id : constant Entity_Id :=
752 Make_Defining_Identifier (Loc,
753 New_Internal_Name ('T'));
758 Make_Full_Type_Declaration (Loc,
759 Defining_Identifier => Def_Id,
761 Make_Access_To_Object_Definition (Loc,
763 Null_Exclusion_Present => False,
764 Constant_Present => False,
765 Subtype_Indication =>
766 New_Reference_To (Etype (Exp), Loc)));
768 Insert_Action (N, New_Decl);
770 -- Inherit the final chain to ensure that the expansion of the
771 -- aggregate is correct in case of controlled types
773 if Needs_Finalization (Directly_Designated_Type (PtrT)) then
774 Set_Associated_Final_Chain (Def_Id,
775 Associated_Final_Chain (PtrT));
778 -- Declare the object using the previous type declaration
780 if Aggr_In_Place then
782 Make_Object_Declaration (Loc,
783 Defining_Identifier => Temp,
784 Object_Definition => New_Reference_To (Def_Id, Loc),
787 New_Reference_To (Etype (Exp), Loc)));
789 -- Copy the Comes_From_Source flag for the allocator we just
790 -- built, since logically this allocator is a replacement of
791 -- the original allocator node. This is for proper handling
792 -- of restriction No_Implicit_Heap_Allocations.
794 Set_Comes_From_Source
795 (Expression (Tmp_Node), Comes_From_Source (N));
797 Set_No_Initialization (Expression (Tmp_Node));
798 Insert_Action (N, Tmp_Node);
800 if Needs_Finalization (T)
801 and then Ekind (PtrT) = E_Anonymous_Access_Type
803 -- Create local finalization list for access parameter
806 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
809 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
811 Node := Relocate_Node (N);
814 Make_Object_Declaration (Loc,
815 Defining_Identifier => Temp,
816 Constant_Present => True,
817 Object_Definition => New_Reference_To (Def_Id, Loc),
818 Expression => Node));
821 -- Generate an additional object containing the address of the
822 -- returned object. The type of this second object declaration
823 -- is the correct type required for the common processing that
824 -- is still performed by this subprogram. The displacement of
825 -- this pointer to reference the component associated with the
826 -- interface type will be done at the end of common processing.
829 Make_Object_Declaration (Loc,
830 Defining_Identifier => Make_Defining_Identifier (Loc,
831 New_Internal_Name ('P')),
832 Object_Definition => New_Reference_To (PtrT, Loc),
833 Expression => Unchecked_Convert_To (PtrT,
834 New_Reference_To (Temp, Loc)));
836 Insert_Action (N, New_Decl);
838 Tmp_Node := New_Decl;
839 Temp := Defining_Identifier (New_Decl);
843 Apply_Accessibility_Check (Temp);
845 -- Generate the tag assignment
847 -- Suppress the tag assignment when VM_Target because VM tags are
848 -- represented implicitly in objects.
850 if not Tagged_Type_Expansion then
853 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
854 -- interface objects because in this case the tag does not change.
856 elsif Is_Interface (Directly_Designated_Type (Etype (N))) then
857 pragma Assert (Is_Class_Wide_Type
858 (Directly_Designated_Type (Etype (N))));
861 elsif Is_Tagged_Type (T) and then not Is_Class_Wide_Type (T) then
863 TagR := New_Reference_To (Temp, Loc);
865 elsif Is_Private_Type (T)
866 and then Is_Tagged_Type (Underlying_Type (T))
868 TagT := Underlying_Type (T);
870 Unchecked_Convert_To (Underlying_Type (T),
871 Make_Explicit_Dereference (Loc,
872 Prefix => New_Reference_To (Temp, Loc)));
875 if Present (TagT) then
877 Make_Assignment_Statement (Loc,
879 Make_Selected_Component (Loc,
882 New_Reference_To (First_Tag_Component (TagT), Loc)),
885 Unchecked_Convert_To (RTE (RE_Tag),
887 (Elists.Node (First_Elmt (Access_Disp_Table (TagT))),
890 -- The previous assignment has to be done in any case
892 Set_Assignment_OK (Name (Tag_Assign));
893 Insert_Action (N, Tag_Assign);
896 if Needs_Finalization (DesigT)
897 and then Needs_Finalization (T)
901 Apool : constant Entity_Id :=
902 Associated_Storage_Pool (PtrT);
905 -- If it is an allocation on the secondary stack (i.e. a value
906 -- returned from a function), the object is attached on the
907 -- caller side as soon as the call is completed (see
908 -- Expand_Ctrl_Function_Call)
910 if Is_RTE (Apool, RE_SS_Pool) then
912 F : constant Entity_Id :=
913 Make_Defining_Identifier (Loc,
914 New_Internal_Name ('F'));
917 Make_Object_Declaration (Loc,
918 Defining_Identifier => F,
919 Object_Definition => New_Reference_To (RTE
920 (RE_Finalizable_Ptr), Loc)));
922 Flist := New_Reference_To (F, Loc);
923 Attach := Make_Integer_Literal (Loc, 1);
926 -- Normal case, not a secondary stack allocation
929 if Needs_Finalization (T)
930 and then Ekind (PtrT) = E_Anonymous_Access_Type
932 -- Create local finalization list for access parameter
935 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
937 Flist := Find_Final_List (PtrT);
940 Attach := Make_Integer_Literal (Loc, 2);
943 -- Generate an Adjust call if the object will be moved. In Ada
944 -- 2005, the object may be inherently limited, in which case
945 -- there is no Adjust procedure, and the object is built in
946 -- place. In Ada 95, the object can be limited but not
947 -- inherently limited if this allocator came from a return
948 -- statement (we're allocating the result on the secondary
949 -- stack). In that case, the object will be moved, so we _do_
953 and then not Is_Inherently_Limited_Type (T)
959 -- An unchecked conversion is needed in the classwide
960 -- case because the designated type can be an ancestor of
961 -- the subtype mark of the allocator.
963 Unchecked_Convert_To (T,
964 Make_Explicit_Dereference (Loc,
965 Prefix => New_Reference_To (Temp, Loc))),
969 With_Attach => Attach,
975 Rewrite (N, New_Reference_To (Temp, Loc));
976 Analyze_And_Resolve (N, PtrT);
978 -- Ada 2005 (AI-251): Displace the pointer to reference the record
979 -- component containing the secondary dispatch table of the interface
982 if Is_Interface (Directly_Designated_Type (PtrT)) then
983 Displace_Allocator_Pointer (N);
986 elsif Aggr_In_Place then
988 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
990 Make_Object_Declaration (Loc,
991 Defining_Identifier => Temp,
992 Object_Definition => New_Reference_To (PtrT, Loc),
993 Expression => Make_Allocator (Loc,
994 New_Reference_To (Etype (Exp), Loc)));
996 -- Copy the Comes_From_Source flag for the allocator we just built,
997 -- since logically this allocator is a replacement of the original
998 -- allocator node. This is for proper handling of restriction
999 -- No_Implicit_Heap_Allocations.
1001 Set_Comes_From_Source
1002 (Expression (Tmp_Node), Comes_From_Source (N));
1004 Set_No_Initialization (Expression (Tmp_Node));
1005 Insert_Action (N, Tmp_Node);
1006 Convert_Aggr_In_Allocator (N, Tmp_Node, Exp);
1007 Rewrite (N, New_Reference_To (Temp, Loc));
1008 Analyze_And_Resolve (N, PtrT);
1010 elsif Is_Access_Type (T)
1011 and then Can_Never_Be_Null (T)
1013 Install_Null_Excluding_Check (Exp);
1015 elsif Is_Access_Type (DesigT)
1016 and then Nkind (Exp) = N_Allocator
1017 and then Nkind (Expression (Exp)) /= N_Qualified_Expression
1019 -- Apply constraint to designated subtype indication
1021 Apply_Constraint_Check (Expression (Exp),
1022 Designated_Type (DesigT),
1023 No_Sliding => True);
1025 if Nkind (Expression (Exp)) = N_Raise_Constraint_Error then
1027 -- Propagate constraint_error to enclosing allocator
1029 Rewrite (Exp, New_Copy (Expression (Exp)));
1033 -- type A is access T1;
1034 -- X : A := new T2'(...);
1035 -- T1 and T2 can be different subtypes, and we might need to check
1036 -- both constraints. First check against the type of the qualified
1039 Apply_Constraint_Check (Exp, T, No_Sliding => True);
1041 if Do_Range_Check (Exp) then
1042 Set_Do_Range_Check (Exp, False);
1043 Generate_Range_Check (Exp, DesigT, CE_Range_Check_Failed);
1046 -- A check is also needed in cases where the designated subtype is
1047 -- constrained and differs from the subtype given in the qualified
1048 -- expression. Note that the check on the qualified expression does
1049 -- not allow sliding, but this check does (a relaxation from Ada 83).
1051 if Is_Constrained (DesigT)
1052 and then not Subtypes_Statically_Match (T, DesigT)
1054 Apply_Constraint_Check
1055 (Exp, DesigT, No_Sliding => False);
1057 if Do_Range_Check (Exp) then
1058 Set_Do_Range_Check (Exp, False);
1059 Generate_Range_Check (Exp, DesigT, CE_Range_Check_Failed);
1063 -- For an access to unconstrained packed array, GIGI needs to see an
1064 -- expression with a constrained subtype in order to compute the
1065 -- proper size for the allocator.
1067 if Is_Array_Type (T)
1068 and then not Is_Constrained (T)
1069 and then Is_Packed (T)
1072 ConstrT : constant Entity_Id :=
1073 Make_Defining_Identifier (Loc,
1074 Chars => New_Internal_Name ('A'));
1075 Internal_Exp : constant Node_Id := Relocate_Node (Exp);
1078 Make_Subtype_Declaration (Loc,
1079 Defining_Identifier => ConstrT,
1080 Subtype_Indication =>
1081 Make_Subtype_From_Expr (Exp, T)));
1082 Freeze_Itype (ConstrT, Exp);
1083 Rewrite (Exp, OK_Convert_To (ConstrT, Internal_Exp));
1087 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1088 -- to a build-in-place function, then access to the allocated object
1089 -- must be passed to the function. Currently we limit such functions
1090 -- to those with constrained limited result subtypes, but eventually
1091 -- we plan to expand the allowed forms of functions that are treated
1092 -- as build-in-place.
1094 if Ada_Version >= Ada_05
1095 and then Is_Build_In_Place_Function_Call (Exp)
1097 Make_Build_In_Place_Call_In_Allocator (N, Exp);
1102 when RE_Not_Available =>
1104 end Expand_Allocator_Expression;
1106 -----------------------------
1107 -- Expand_Array_Comparison --
1108 -----------------------------
1110 -- Expansion is only required in the case of array types. For the unpacked
1111 -- case, an appropriate runtime routine is called. For packed cases, and
1112 -- also in some other cases where a runtime routine cannot be called, the
1113 -- form of the expansion is:
1115 -- [body for greater_nn; boolean_expression]
1117 -- The body is built by Make_Array_Comparison_Op, and the form of the
1118 -- Boolean expression depends on the operator involved.
1120 procedure Expand_Array_Comparison (N : Node_Id) is
1121 Loc : constant Source_Ptr := Sloc (N);
1122 Op1 : Node_Id := Left_Opnd (N);
1123 Op2 : Node_Id := Right_Opnd (N);
1124 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
1125 Ctyp : constant Entity_Id := Component_Type (Typ1);
1128 Func_Body : Node_Id;
1129 Func_Name : Entity_Id;
1133 Byte_Addressable : constant Boolean := System_Storage_Unit = Byte'Size;
1134 -- True for byte addressable target
1136 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean;
1137 -- Returns True if the length of the given operand is known to be less
1138 -- than 4. Returns False if this length is known to be four or greater
1139 -- or is not known at compile time.
1141 ------------------------
1142 -- Length_Less_Than_4 --
1143 ------------------------
1145 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean is
1146 Otyp : constant Entity_Id := Etype (Opnd);
1149 if Ekind (Otyp) = E_String_Literal_Subtype then
1150 return String_Literal_Length (Otyp) < 4;
1154 Ityp : constant Entity_Id := Etype (First_Index (Otyp));
1155 Lo : constant Node_Id := Type_Low_Bound (Ityp);
1156 Hi : constant Node_Id := Type_High_Bound (Ityp);
1161 if Compile_Time_Known_Value (Lo) then
1162 Lov := Expr_Value (Lo);
1167 if Compile_Time_Known_Value (Hi) then
1168 Hiv := Expr_Value (Hi);
1173 return Hiv < Lov + 3;
1176 end Length_Less_Than_4;
1178 -- Start of processing for Expand_Array_Comparison
1181 -- Deal first with unpacked case, where we can call a runtime routine
1182 -- except that we avoid this for targets for which are not addressable
1183 -- by bytes, and for the JVM/CIL, since they do not support direct
1184 -- addressing of array components.
1186 if not Is_Bit_Packed_Array (Typ1)
1187 and then Byte_Addressable
1188 and then VM_Target = No_VM
1190 -- The call we generate is:
1192 -- Compare_Array_xn[_Unaligned]
1193 -- (left'address, right'address, left'length, right'length) <op> 0
1195 -- x = U for unsigned, S for signed
1196 -- n = 8,16,32,64 for component size
1197 -- Add _Unaligned if length < 4 and component size is 8.
1198 -- <op> is the standard comparison operator
1200 if Component_Size (Typ1) = 8 then
1201 if Length_Less_Than_4 (Op1)
1203 Length_Less_Than_4 (Op2)
1205 if Is_Unsigned_Type (Ctyp) then
1206 Comp := RE_Compare_Array_U8_Unaligned;
1208 Comp := RE_Compare_Array_S8_Unaligned;
1212 if Is_Unsigned_Type (Ctyp) then
1213 Comp := RE_Compare_Array_U8;
1215 Comp := RE_Compare_Array_S8;
1219 elsif Component_Size (Typ1) = 16 then
1220 if Is_Unsigned_Type (Ctyp) then
1221 Comp := RE_Compare_Array_U16;
1223 Comp := RE_Compare_Array_S16;
1226 elsif Component_Size (Typ1) = 32 then
1227 if Is_Unsigned_Type (Ctyp) then
1228 Comp := RE_Compare_Array_U32;
1230 Comp := RE_Compare_Array_S32;
1233 else pragma Assert (Component_Size (Typ1) = 64);
1234 if Is_Unsigned_Type (Ctyp) then
1235 Comp := RE_Compare_Array_U64;
1237 Comp := RE_Compare_Array_S64;
1241 Remove_Side_Effects (Op1, Name_Req => True);
1242 Remove_Side_Effects (Op2, Name_Req => True);
1245 Make_Function_Call (Sloc (Op1),
1246 Name => New_Occurrence_Of (RTE (Comp), Loc),
1248 Parameter_Associations => New_List (
1249 Make_Attribute_Reference (Loc,
1250 Prefix => Relocate_Node (Op1),
1251 Attribute_Name => Name_Address),
1253 Make_Attribute_Reference (Loc,
1254 Prefix => Relocate_Node (Op2),
1255 Attribute_Name => Name_Address),
1257 Make_Attribute_Reference (Loc,
1258 Prefix => Relocate_Node (Op1),
1259 Attribute_Name => Name_Length),
1261 Make_Attribute_Reference (Loc,
1262 Prefix => Relocate_Node (Op2),
1263 Attribute_Name => Name_Length))));
1266 Make_Integer_Literal (Sloc (Op2),
1269 Analyze_And_Resolve (Op1, Standard_Integer);
1270 Analyze_And_Resolve (Op2, Standard_Integer);
1274 -- Cases where we cannot make runtime call
1276 -- For (a <= b) we convert to not (a > b)
1278 if Chars (N) = Name_Op_Le then
1284 Right_Opnd => Op2)));
1285 Analyze_And_Resolve (N, Standard_Boolean);
1288 -- For < the Boolean expression is
1289 -- greater__nn (op2, op1)
1291 elsif Chars (N) = Name_Op_Lt then
1292 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1296 Op1 := Right_Opnd (N);
1297 Op2 := Left_Opnd (N);
1299 -- For (a >= b) we convert to not (a < b)
1301 elsif Chars (N) = Name_Op_Ge then
1307 Right_Opnd => Op2)));
1308 Analyze_And_Resolve (N, Standard_Boolean);
1311 -- For > the Boolean expression is
1312 -- greater__nn (op1, op2)
1315 pragma Assert (Chars (N) = Name_Op_Gt);
1316 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1319 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1321 Make_Function_Call (Loc,
1322 Name => New_Reference_To (Func_Name, Loc),
1323 Parameter_Associations => New_List (Op1, Op2));
1325 Insert_Action (N, Func_Body);
1327 Analyze_And_Resolve (N, Standard_Boolean);
1330 when RE_Not_Available =>
1332 end Expand_Array_Comparison;
1334 ---------------------------
1335 -- Expand_Array_Equality --
1336 ---------------------------
1338 -- Expand an equality function for multi-dimensional arrays. Here is an
1339 -- example of such a function for Nb_Dimension = 2
1341 -- function Enn (A : atyp; B : btyp) return boolean is
1343 -- if (A'length (1) = 0 or else A'length (2) = 0)
1345 -- (B'length (1) = 0 or else B'length (2) = 0)
1347 -- return True; -- RM 4.5.2(22)
1350 -- if A'length (1) /= B'length (1)
1352 -- A'length (2) /= B'length (2)
1354 -- return False; -- RM 4.5.2(23)
1358 -- A1 : Index_T1 := A'first (1);
1359 -- B1 : Index_T1 := B'first (1);
1363 -- A2 : Index_T2 := A'first (2);
1364 -- B2 : Index_T2 := B'first (2);
1367 -- if A (A1, A2) /= B (B1, B2) then
1371 -- exit when A2 = A'last (2);
1372 -- A2 := Index_T2'succ (A2);
1373 -- B2 := Index_T2'succ (B2);
1377 -- exit when A1 = A'last (1);
1378 -- A1 := Index_T1'succ (A1);
1379 -- B1 := Index_T1'succ (B1);
1386 -- Note on the formal types used (atyp and btyp). If either of the arrays
1387 -- is of a private type, we use the underlying type, and do an unchecked
1388 -- conversion of the actual. If either of the arrays has a bound depending
1389 -- on a discriminant, then we use the base type since otherwise we have an
1390 -- escaped discriminant in the function.
1392 -- If both arrays are constrained and have the same bounds, we can generate
1393 -- a loop with an explicit iteration scheme using a 'Range attribute over
1396 function Expand_Array_Equality
1401 Typ : Entity_Id) return Node_Id
1403 Loc : constant Source_Ptr := Sloc (Nod);
1404 Decls : constant List_Id := New_List;
1405 Index_List1 : constant List_Id := New_List;
1406 Index_List2 : constant List_Id := New_List;
1410 Func_Name : Entity_Id;
1411 Func_Body : Node_Id;
1413 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
1414 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
1418 -- The parameter types to be used for the formals
1423 Num : Int) return Node_Id;
1424 -- This builds the attribute reference Arr'Nam (Expr)
1426 function Component_Equality (Typ : Entity_Id) return Node_Id;
1427 -- Create one statement to compare corresponding components, designated
1428 -- by a full set of indices.
1430 function Get_Arg_Type (N : Node_Id) return Entity_Id;
1431 -- Given one of the arguments, computes the appropriate type to be used
1432 -- for that argument in the corresponding function formal
1434 function Handle_One_Dimension
1436 Index : Node_Id) return Node_Id;
1437 -- This procedure returns the following code
1440 -- Bn : Index_T := B'First (N);
1444 -- exit when An = A'Last (N);
1445 -- An := Index_T'Succ (An)
1446 -- Bn := Index_T'Succ (Bn)
1450 -- If both indices are constrained and identical, the procedure
1451 -- returns a simpler loop:
1453 -- for An in A'Range (N) loop
1457 -- N is the dimension for which we are generating a loop. Index is the
1458 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1459 -- xxx statement is either the loop or declare for the next dimension
1460 -- or if this is the last dimension the comparison of corresponding
1461 -- components of the arrays.
1463 -- The actual way the code works is to return the comparison of
1464 -- corresponding components for the N+1 call. That's neater!
1466 function Test_Empty_Arrays return Node_Id;
1467 -- This function constructs the test for both arrays being empty
1468 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1470 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1472 function Test_Lengths_Correspond return Node_Id;
1473 -- This function constructs the test for arrays having different lengths
1474 -- in at least one index position, in which case the resulting code is:
1476 -- A'length (1) /= B'length (1)
1478 -- A'length (2) /= B'length (2)
1489 Num : Int) return Node_Id
1493 Make_Attribute_Reference (Loc,
1494 Attribute_Name => Nam,
1495 Prefix => New_Reference_To (Arr, Loc),
1496 Expressions => New_List (Make_Integer_Literal (Loc, Num)));
1499 ------------------------
1500 -- Component_Equality --
1501 ------------------------
1503 function Component_Equality (Typ : Entity_Id) return Node_Id is
1508 -- if a(i1...) /= b(j1...) then return false; end if;
1511 Make_Indexed_Component (Loc,
1512 Prefix => Make_Identifier (Loc, Chars (A)),
1513 Expressions => Index_List1);
1516 Make_Indexed_Component (Loc,
1517 Prefix => Make_Identifier (Loc, Chars (B)),
1518 Expressions => Index_List2);
1520 Test := Expand_Composite_Equality
1521 (Nod, Component_Type (Typ), L, R, Decls);
1523 -- If some (sub)component is an unchecked_union, the whole operation
1524 -- will raise program error.
1526 if Nkind (Test) = N_Raise_Program_Error then
1528 -- This node is going to be inserted at a location where a
1529 -- statement is expected: clear its Etype so analysis will set
1530 -- it to the expected Standard_Void_Type.
1532 Set_Etype (Test, Empty);
1537 Make_Implicit_If_Statement (Nod,
1538 Condition => Make_Op_Not (Loc, Right_Opnd => Test),
1539 Then_Statements => New_List (
1540 Make_Simple_Return_Statement (Loc,
1541 Expression => New_Occurrence_Of (Standard_False, Loc))));
1543 end Component_Equality;
1549 function Get_Arg_Type (N : Node_Id) return Entity_Id is
1560 T := Underlying_Type (T);
1562 X := First_Index (T);
1563 while Present (X) loop
1564 if Denotes_Discriminant (Type_Low_Bound (Etype (X)))
1566 Denotes_Discriminant (Type_High_Bound (Etype (X)))
1579 --------------------------
1580 -- Handle_One_Dimension --
1581 ---------------------------
1583 function Handle_One_Dimension
1585 Index : Node_Id) return Node_Id
1587 Need_Separate_Indexes : constant Boolean :=
1589 or else not Is_Constrained (Ltyp);
1590 -- If the index types are identical, and we are working with
1591 -- constrained types, then we can use the same index for both
1594 An : constant Entity_Id := Make_Defining_Identifier (Loc,
1595 Chars => New_Internal_Name ('A'));
1598 Index_T : Entity_Id;
1603 if N > Number_Dimensions (Ltyp) then
1604 return Component_Equality (Ltyp);
1607 -- Case where we generate a loop
1609 Index_T := Base_Type (Etype (Index));
1611 if Need_Separate_Indexes then
1613 Make_Defining_Identifier (Loc,
1614 Chars => New_Internal_Name ('B'));
1619 Append (New_Reference_To (An, Loc), Index_List1);
1620 Append (New_Reference_To (Bn, Loc), Index_List2);
1622 Stm_List := New_List (
1623 Handle_One_Dimension (N + 1, Next_Index (Index)));
1625 if Need_Separate_Indexes then
1627 -- Generate guard for loop, followed by increments of indices
1629 Append_To (Stm_List,
1630 Make_Exit_Statement (Loc,
1633 Left_Opnd => New_Reference_To (An, Loc),
1634 Right_Opnd => Arr_Attr (A, Name_Last, N))));
1636 Append_To (Stm_List,
1637 Make_Assignment_Statement (Loc,
1638 Name => New_Reference_To (An, Loc),
1640 Make_Attribute_Reference (Loc,
1641 Prefix => New_Reference_To (Index_T, Loc),
1642 Attribute_Name => Name_Succ,
1643 Expressions => New_List (New_Reference_To (An, Loc)))));
1645 Append_To (Stm_List,
1646 Make_Assignment_Statement (Loc,
1647 Name => New_Reference_To (Bn, Loc),
1649 Make_Attribute_Reference (Loc,
1650 Prefix => New_Reference_To (Index_T, Loc),
1651 Attribute_Name => Name_Succ,
1652 Expressions => New_List (New_Reference_To (Bn, Loc)))));
1655 -- If separate indexes, we need a declare block for An and Bn, and a
1656 -- loop without an iteration scheme.
1658 if Need_Separate_Indexes then
1660 Make_Implicit_Loop_Statement (Nod, Statements => Stm_List);
1663 Make_Block_Statement (Loc,
1664 Declarations => New_List (
1665 Make_Object_Declaration (Loc,
1666 Defining_Identifier => An,
1667 Object_Definition => New_Reference_To (Index_T, Loc),
1668 Expression => Arr_Attr (A, Name_First, N)),
1670 Make_Object_Declaration (Loc,
1671 Defining_Identifier => Bn,
1672 Object_Definition => New_Reference_To (Index_T, Loc),
1673 Expression => Arr_Attr (B, Name_First, N))),
1675 Handled_Statement_Sequence =>
1676 Make_Handled_Sequence_Of_Statements (Loc,
1677 Statements => New_List (Loop_Stm)));
1679 -- If no separate indexes, return loop statement with explicit
1680 -- iteration scheme on its own
1684 Make_Implicit_Loop_Statement (Nod,
1685 Statements => Stm_List,
1687 Make_Iteration_Scheme (Loc,
1688 Loop_Parameter_Specification =>
1689 Make_Loop_Parameter_Specification (Loc,
1690 Defining_Identifier => An,
1691 Discrete_Subtype_Definition =>
1692 Arr_Attr (A, Name_Range, N))));
1695 end Handle_One_Dimension;
1697 -----------------------
1698 -- Test_Empty_Arrays --
1699 -----------------------
1701 function Test_Empty_Arrays return Node_Id is
1711 for J in 1 .. Number_Dimensions (Ltyp) loop
1714 Left_Opnd => Arr_Attr (A, Name_Length, J),
1715 Right_Opnd => Make_Integer_Literal (Loc, 0));
1719 Left_Opnd => Arr_Attr (B, Name_Length, J),
1720 Right_Opnd => Make_Integer_Literal (Loc, 0));
1729 Left_Opnd => Relocate_Node (Alist),
1730 Right_Opnd => Atest);
1734 Left_Opnd => Relocate_Node (Blist),
1735 Right_Opnd => Btest);
1742 Right_Opnd => Blist);
1743 end Test_Empty_Arrays;
1745 -----------------------------
1746 -- Test_Lengths_Correspond --
1747 -----------------------------
1749 function Test_Lengths_Correspond return Node_Id is
1755 for J in 1 .. Number_Dimensions (Ltyp) loop
1758 Left_Opnd => Arr_Attr (A, Name_Length, J),
1759 Right_Opnd => Arr_Attr (B, Name_Length, J));
1766 Left_Opnd => Relocate_Node (Result),
1767 Right_Opnd => Rtest);
1772 end Test_Lengths_Correspond;
1774 -- Start of processing for Expand_Array_Equality
1777 Ltyp := Get_Arg_Type (Lhs);
1778 Rtyp := Get_Arg_Type (Rhs);
1780 -- For now, if the argument types are not the same, go to the base type,
1781 -- since the code assumes that the formals have the same type. This is
1782 -- fixable in future ???
1784 if Ltyp /= Rtyp then
1785 Ltyp := Base_Type (Ltyp);
1786 Rtyp := Base_Type (Rtyp);
1787 pragma Assert (Ltyp = Rtyp);
1790 -- Build list of formals for function
1792 Formals := New_List (
1793 Make_Parameter_Specification (Loc,
1794 Defining_Identifier => A,
1795 Parameter_Type => New_Reference_To (Ltyp, Loc)),
1797 Make_Parameter_Specification (Loc,
1798 Defining_Identifier => B,
1799 Parameter_Type => New_Reference_To (Rtyp, Loc)));
1801 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('E'));
1803 -- Build statement sequence for function
1806 Make_Subprogram_Body (Loc,
1808 Make_Function_Specification (Loc,
1809 Defining_Unit_Name => Func_Name,
1810 Parameter_Specifications => Formals,
1811 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
1813 Declarations => Decls,
1815 Handled_Statement_Sequence =>
1816 Make_Handled_Sequence_Of_Statements (Loc,
1817 Statements => New_List (
1819 Make_Implicit_If_Statement (Nod,
1820 Condition => Test_Empty_Arrays,
1821 Then_Statements => New_List (
1822 Make_Simple_Return_Statement (Loc,
1824 New_Occurrence_Of (Standard_True, Loc)))),
1826 Make_Implicit_If_Statement (Nod,
1827 Condition => Test_Lengths_Correspond,
1828 Then_Statements => New_List (
1829 Make_Simple_Return_Statement (Loc,
1831 New_Occurrence_Of (Standard_False, Loc)))),
1833 Handle_One_Dimension (1, First_Index (Ltyp)),
1835 Make_Simple_Return_Statement (Loc,
1836 Expression => New_Occurrence_Of (Standard_True, Loc)))));
1838 Set_Has_Completion (Func_Name, True);
1839 Set_Is_Inlined (Func_Name);
1841 -- If the array type is distinct from the type of the arguments, it
1842 -- is the full view of a private type. Apply an unchecked conversion
1843 -- to insure that analysis of the call succeeds.
1853 or else Base_Type (Etype (Lhs)) /= Base_Type (Ltyp)
1855 L := OK_Convert_To (Ltyp, Lhs);
1859 or else Base_Type (Etype (Rhs)) /= Base_Type (Rtyp)
1861 R := OK_Convert_To (Rtyp, Rhs);
1864 Actuals := New_List (L, R);
1867 Append_To (Bodies, Func_Body);
1870 Make_Function_Call (Loc,
1871 Name => New_Reference_To (Func_Name, Loc),
1872 Parameter_Associations => Actuals);
1873 end Expand_Array_Equality;
1875 -----------------------------
1876 -- Expand_Boolean_Operator --
1877 -----------------------------
1879 -- Note that we first get the actual subtypes of the operands, since we
1880 -- always want to deal with types that have bounds.
1882 procedure Expand_Boolean_Operator (N : Node_Id) is
1883 Typ : constant Entity_Id := Etype (N);
1886 -- Special case of bit packed array where both operands are known to be
1887 -- properly aligned. In this case we use an efficient run time routine
1888 -- to carry out the operation (see System.Bit_Ops).
1890 if Is_Bit_Packed_Array (Typ)
1891 and then not Is_Possibly_Unaligned_Object (Left_Opnd (N))
1892 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
1894 Expand_Packed_Boolean_Operator (N);
1898 -- For the normal non-packed case, the general expansion is to build
1899 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
1900 -- and then inserting it into the tree. The original operator node is
1901 -- then rewritten as a call to this function. We also use this in the
1902 -- packed case if either operand is a possibly unaligned object.
1905 Loc : constant Source_Ptr := Sloc (N);
1906 L : constant Node_Id := Relocate_Node (Left_Opnd (N));
1907 R : constant Node_Id := Relocate_Node (Right_Opnd (N));
1908 Func_Body : Node_Id;
1909 Func_Name : Entity_Id;
1912 Convert_To_Actual_Subtype (L);
1913 Convert_To_Actual_Subtype (R);
1914 Ensure_Defined (Etype (L), N);
1915 Ensure_Defined (Etype (R), N);
1916 Apply_Length_Check (R, Etype (L));
1918 if Nkind (N) = N_Op_Xor then
1919 Silly_Boolean_Array_Xor_Test (N, Etype (L));
1922 if Nkind (Parent (N)) = N_Assignment_Statement
1923 and then Safe_In_Place_Array_Op (Name (Parent (N)), L, R)
1925 Build_Boolean_Array_Proc_Call (Parent (N), L, R);
1927 elsif Nkind (Parent (N)) = N_Op_Not
1928 and then Nkind (N) = N_Op_And
1930 Safe_In_Place_Array_Op (Name (Parent (Parent (N))), L, R)
1935 Func_Body := Make_Boolean_Array_Op (Etype (L), N);
1936 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1937 Insert_Action (N, Func_Body);
1939 -- Now rewrite the expression with a call
1942 Make_Function_Call (Loc,
1943 Name => New_Reference_To (Func_Name, Loc),
1944 Parameter_Associations =>
1947 Make_Type_Conversion
1948 (Loc, New_Reference_To (Etype (L), Loc), R))));
1950 Analyze_And_Resolve (N, Typ);
1953 end Expand_Boolean_Operator;
1955 -------------------------------
1956 -- Expand_Composite_Equality --
1957 -------------------------------
1959 -- This function is only called for comparing internal fields of composite
1960 -- types when these fields are themselves composites. This is a special
1961 -- case because it is not possible to respect normal Ada visibility rules.
1963 function Expand_Composite_Equality
1968 Bodies : List_Id) return Node_Id
1970 Loc : constant Source_Ptr := Sloc (Nod);
1971 Full_Type : Entity_Id;
1976 if Is_Private_Type (Typ) then
1977 Full_Type := Underlying_Type (Typ);
1982 -- Defense against malformed private types with no completion the error
1983 -- will be diagnosed later by check_completion
1985 if No (Full_Type) then
1986 return New_Reference_To (Standard_False, Loc);
1989 Full_Type := Base_Type (Full_Type);
1991 if Is_Array_Type (Full_Type) then
1993 -- If the operand is an elementary type other than a floating-point
1994 -- type, then we can simply use the built-in block bitwise equality,
1995 -- since the predefined equality operators always apply and bitwise
1996 -- equality is fine for all these cases.
1998 if Is_Elementary_Type (Component_Type (Full_Type))
1999 and then not Is_Floating_Point_Type (Component_Type (Full_Type))
2001 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2003 -- For composite component types, and floating-point types, use the
2004 -- expansion. This deals with tagged component types (where we use
2005 -- the applicable equality routine) and floating-point, (where we
2006 -- need to worry about negative zeroes), and also the case of any
2007 -- composite type recursively containing such fields.
2010 return Expand_Array_Equality (Nod, Lhs, Rhs, Bodies, Full_Type);
2013 elsif Is_Tagged_Type (Full_Type) then
2015 -- Call the primitive operation "=" of this type
2017 if Is_Class_Wide_Type (Full_Type) then
2018 Full_Type := Root_Type (Full_Type);
2021 -- If this is derived from an untagged private type completed with a
2022 -- tagged type, it does not have a full view, so we use the primitive
2023 -- operations of the private type. This check should no longer be
2024 -- necessary when these types receive their full views ???
2026 if Is_Private_Type (Typ)
2027 and then not Is_Tagged_Type (Typ)
2028 and then not Is_Controlled (Typ)
2029 and then Is_Derived_Type (Typ)
2030 and then No (Full_View (Typ))
2032 Prim := First_Elmt (Collect_Primitive_Operations (Typ));
2034 Prim := First_Elmt (Primitive_Operations (Full_Type));
2038 Eq_Op := Node (Prim);
2039 exit when Chars (Eq_Op) = Name_Op_Eq
2040 and then Etype (First_Formal (Eq_Op)) =
2041 Etype (Next_Formal (First_Formal (Eq_Op)))
2042 and then Base_Type (Etype (Eq_Op)) = Standard_Boolean;
2044 pragma Assert (Present (Prim));
2047 Eq_Op := Node (Prim);
2050 Make_Function_Call (Loc,
2051 Name => New_Reference_To (Eq_Op, Loc),
2052 Parameter_Associations =>
2054 (Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Lhs),
2055 Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Rhs)));
2057 elsif Is_Record_Type (Full_Type) then
2058 Eq_Op := TSS (Full_Type, TSS_Composite_Equality);
2060 if Present (Eq_Op) then
2061 if Etype (First_Formal (Eq_Op)) /= Full_Type then
2063 -- Inherited equality from parent type. Convert the actuals to
2064 -- match signature of operation.
2067 T : constant Entity_Id := Etype (First_Formal (Eq_Op));
2071 Make_Function_Call (Loc,
2072 Name => New_Reference_To (Eq_Op, Loc),
2073 Parameter_Associations =>
2074 New_List (OK_Convert_To (T, Lhs),
2075 OK_Convert_To (T, Rhs)));
2079 -- Comparison between Unchecked_Union components
2081 if Is_Unchecked_Union (Full_Type) then
2083 Lhs_Type : Node_Id := Full_Type;
2084 Rhs_Type : Node_Id := Full_Type;
2085 Lhs_Discr_Val : Node_Id;
2086 Rhs_Discr_Val : Node_Id;
2091 if Nkind (Lhs) = N_Selected_Component then
2092 Lhs_Type := Etype (Entity (Selector_Name (Lhs)));
2097 if Nkind (Rhs) = N_Selected_Component then
2098 Rhs_Type := Etype (Entity (Selector_Name (Rhs)));
2101 -- Lhs of the composite equality
2103 if Is_Constrained (Lhs_Type) then
2105 -- Since the enclosing record type can never be an
2106 -- Unchecked_Union (this code is executed for records
2107 -- that do not have variants), we may reference its
2110 if Nkind (Lhs) = N_Selected_Component
2111 and then Has_Per_Object_Constraint (
2112 Entity (Selector_Name (Lhs)))
2115 Make_Selected_Component (Loc,
2116 Prefix => Prefix (Lhs),
2119 Get_Discriminant_Value (
2120 First_Discriminant (Lhs_Type),
2122 Stored_Constraint (Lhs_Type))));
2125 Lhs_Discr_Val := New_Copy (
2126 Get_Discriminant_Value (
2127 First_Discriminant (Lhs_Type),
2129 Stored_Constraint (Lhs_Type)));
2133 -- It is not possible to infer the discriminant since
2134 -- the subtype is not constrained.
2137 Make_Raise_Program_Error (Loc,
2138 Reason => PE_Unchecked_Union_Restriction);
2141 -- Rhs of the composite equality
2143 if Is_Constrained (Rhs_Type) then
2144 if Nkind (Rhs) = N_Selected_Component
2145 and then Has_Per_Object_Constraint (
2146 Entity (Selector_Name (Rhs)))
2149 Make_Selected_Component (Loc,
2150 Prefix => Prefix (Rhs),
2153 Get_Discriminant_Value (
2154 First_Discriminant (Rhs_Type),
2156 Stored_Constraint (Rhs_Type))));
2159 Rhs_Discr_Val := New_Copy (
2160 Get_Discriminant_Value (
2161 First_Discriminant (Rhs_Type),
2163 Stored_Constraint (Rhs_Type)));
2168 Make_Raise_Program_Error (Loc,
2169 Reason => PE_Unchecked_Union_Restriction);
2172 -- Call the TSS equality function with the inferred
2173 -- discriminant values.
2176 Make_Function_Call (Loc,
2177 Name => New_Reference_To (Eq_Op, Loc),
2178 Parameter_Associations => New_List (
2186 -- Shouldn't this be an else, we can't fall through the above
2190 Make_Function_Call (Loc,
2191 Name => New_Reference_To (Eq_Op, Loc),
2192 Parameter_Associations => New_List (Lhs, Rhs));
2196 return Expand_Record_Equality (Nod, Full_Type, Lhs, Rhs, Bodies);
2200 -- It can be a simple record or the full view of a scalar private
2202 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2204 end Expand_Composite_Equality;
2206 ------------------------
2207 -- Expand_Concatenate --
2208 ------------------------
2210 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id) is
2211 Loc : constant Source_Ptr := Sloc (Cnode);
2213 Atyp : constant Entity_Id := Base_Type (Etype (Cnode));
2214 -- Result type of concatenation
2216 Ctyp : constant Entity_Id := Base_Type (Component_Type (Etype (Cnode)));
2217 -- Component type. Elements of this component type can appear as one
2218 -- of the operands of concatenation as well as arrays.
2220 Istyp : constant Entity_Id := Etype (First_Index (Atyp));
2223 Ityp : constant Entity_Id := Base_Type (Istyp);
2224 -- Index type. This is the base type of the index subtype, and is used
2225 -- for all computed bounds (which may be out of range of Istyp in the
2226 -- case of null ranges).
2229 -- This is the type we use to do arithmetic to compute the bounds and
2230 -- lengths of operands. The choice of this type is a little subtle and
2231 -- is discussed in a separate section at the start of the body code.
2233 Concatenation_Error : exception;
2234 -- Raised if concatenation is sure to raise a CE
2236 Result_May_Be_Null : Boolean := True;
2237 -- Reset to False if at least one operand is encountered which is known
2238 -- at compile time to be non-null. Used for handling the special case
2239 -- of setting the high bound to the last operand high bound for a null
2240 -- result, thus ensuring a proper high bound in the super-flat case.
2242 N : constant Nat := List_Length (Opnds);
2243 -- Number of concatenation operands including possibly null operands
2246 -- Number of operands excluding any known to be null, except that the
2247 -- last operand is always retained, in case it provides the bounds for
2251 -- Current operand being processed in the loop through operands. After
2252 -- this loop is complete, always contains the last operand (which is not
2253 -- the same as Operands (NN), since null operands are skipped).
2255 -- Arrays describing the operands, only the first NN entries of each
2256 -- array are set (NN < N when we exclude known null operands).
2258 Is_Fixed_Length : array (1 .. N) of Boolean;
2259 -- True if length of corresponding operand known at compile time
2261 Operands : array (1 .. N) of Node_Id;
2262 -- Set to the corresponding entry in the Opnds list (but note that null
2263 -- operands are excluded, so not all entries in the list are stored).
2265 Fixed_Length : array (1 .. N) of Uint;
2266 -- Set to length of operand. Entries in this array are set only if the
2267 -- corresponding entry in Is_Fixed_Length is True.
2269 Opnd_Low_Bound : array (1 .. N) of Node_Id;
2270 -- Set to lower bound of operand. Either an integer literal in the case
2271 -- where the bound is known at compile time, else actual lower bound.
2272 -- The operand low bound is of type Ityp.
2274 Var_Length : array (1 .. N) of Entity_Id;
2275 -- Set to an entity of type Natural that contains the length of an
2276 -- operand whose length is not known at compile time. Entries in this
2277 -- array are set only if the corresponding entry in Is_Fixed_Length
2278 -- is False. The entity is of type Artyp.
2280 Aggr_Length : array (0 .. N) of Node_Id;
2281 -- The J'th entry in an expression node that represents the total length
2282 -- of operands 1 through J. It is either an integer literal node, or a
2283 -- reference to a constant entity with the right value, so it is fine
2284 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2285 -- entry always is set to zero. The length is of type Artyp.
2287 Low_Bound : Node_Id;
2288 -- A tree node representing the low bound of the result (of type Ityp).
2289 -- This is either an integer literal node, or an identifier reference to
2290 -- a constant entity initialized to the appropriate value.
2292 Last_Opnd_High_Bound : Node_Id;
2293 -- A tree node representing the high bound of the last operand. This
2294 -- need only be set if the result could be null. It is used for the
2295 -- special case of setting the right high bound for a null result.
2296 -- This is of type Ityp.
2298 High_Bound : Node_Id;
2299 -- A tree node representing the high bound of the result (of type Ityp)
2302 -- Result of the concatenation (of type Ityp)
2304 Actions : constant List_Id := New_List;
2305 -- Collect actions to be inserted if Save_Space is False
2307 Save_Space : Boolean;
2308 pragma Warnings (Off, Save_Space);
2309 -- Set to True if we are saving generated code space by calling routines
2310 -- in packages System.Concat_n.
2312 Known_Non_Null_Operand_Seen : Boolean;
2313 -- Set True during generation of the assignements of operands into
2314 -- result once an operand known to be non-null has been seen.
2316 function Make_Artyp_Literal (Val : Nat) return Node_Id;
2317 -- This function makes an N_Integer_Literal node that is returned in
2318 -- analyzed form with the type set to Artyp. Importantly this literal
2319 -- is not flagged as static, so that if we do computations with it that
2320 -- result in statically detected out of range conditions, we will not
2321 -- generate error messages but instead warning messages.
2323 function To_Artyp (X : Node_Id) return Node_Id;
2324 -- Given a node of type Ityp, returns the corresponding value of type
2325 -- Artyp. For non-enumeration types, this is a plain integer conversion.
2326 -- For enum types, the Pos of the value is returned.
2328 function To_Ityp (X : Node_Id) return Node_Id;
2329 -- The inverse function (uses Val in the case of enumeration types)
2331 ------------------------
2332 -- Make_Artyp_Literal --
2333 ------------------------
2335 function Make_Artyp_Literal (Val : Nat) return Node_Id is
2336 Result : constant Node_Id := Make_Integer_Literal (Loc, Val);
2338 Set_Etype (Result, Artyp);
2339 Set_Analyzed (Result, True);
2340 Set_Is_Static_Expression (Result, False);
2342 end Make_Artyp_Literal;
2348 function To_Artyp (X : Node_Id) return Node_Id is
2350 if Ityp = Base_Type (Artyp) then
2353 elsif Is_Enumeration_Type (Ityp) then
2355 Make_Attribute_Reference (Loc,
2356 Prefix => New_Occurrence_Of (Ityp, Loc),
2357 Attribute_Name => Name_Pos,
2358 Expressions => New_List (X));
2361 return Convert_To (Artyp, X);
2369 function To_Ityp (X : Node_Id) return Node_Id is
2371 if Is_Enumeration_Type (Ityp) then
2373 Make_Attribute_Reference (Loc,
2374 Prefix => New_Occurrence_Of (Ityp, Loc),
2375 Attribute_Name => Name_Val,
2376 Expressions => New_List (X));
2378 -- Case where we will do a type conversion
2381 if Ityp = Base_Type (Artyp) then
2384 return Convert_To (Ityp, X);
2389 -- Local Declarations
2391 Opnd_Typ : Entity_Id;
2399 -- Choose an appropriate computational type
2401 -- We will be doing calculations of lengths and bounds in this routine
2402 -- and computing one from the other in some cases, e.g. getting the high
2403 -- bound by adding the length-1 to the low bound.
2405 -- We can't just use the index type, or even its base type for this
2406 -- purpose for two reasons. First it might be an enumeration type which
2407 -- is not suitable fo computations of any kind, and second it may simply
2408 -- not have enough range. For example if the index type is -128..+127
2409 -- then lengths can be up to 256, which is out of range of the type.
2411 -- For enumeration types, we can simply use Standard_Integer, this is
2412 -- sufficient since the actual number of enumeration literals cannot
2413 -- possibly exceed the range of integer (remember we will be doing the
2414 -- arithmetic with POS values, not representation values).
2416 if Is_Enumeration_Type (Ityp) then
2417 Artyp := Standard_Integer;
2419 -- If index type is Positive, we use the standard unsigned type, to give
2420 -- more room on the top of the range, obviating the need for an overflow
2421 -- check when creating the upper bound. This is needed to avoid junk
2422 -- overflow checks in the common case of String types.
2424 -- ??? Disabled for now
2426 -- elsif Istyp = Standard_Positive then
2427 -- Artyp := Standard_Unsigned;
2429 -- For modular types, we use a 32-bit modular type for types whose size
2430 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
2431 -- identity type, and for larger unsigned types we use 64-bits.
2433 elsif Is_Modular_Integer_Type (Ityp) then
2434 if RM_Size (Ityp) < RM_Size (Standard_Unsigned) then
2435 Artyp := Standard_Unsigned;
2436 elsif RM_Size (Ityp) = RM_Size (Standard_Unsigned) then
2439 Artyp := RTE (RE_Long_Long_Unsigned);
2442 -- Similar treatment for signed types
2445 if RM_Size (Ityp) < RM_Size (Standard_Integer) then
2446 Artyp := Standard_Integer;
2447 elsif RM_Size (Ityp) = RM_Size (Standard_Integer) then
2450 Artyp := Standard_Long_Long_Integer;
2454 -- Supply dummy entry at start of length array
2456 Aggr_Length (0) := Make_Artyp_Literal (0);
2458 -- Go through operands setting up the above arrays
2462 Opnd := Remove_Head (Opnds);
2463 Opnd_Typ := Etype (Opnd);
2465 -- The parent got messed up when we put the operands in a list,
2466 -- so now put back the proper parent for the saved operand.
2468 Set_Parent (Opnd, Parent (Cnode));
2470 -- Set will be True when we have setup one entry in the array
2474 -- Singleton element (or character literal) case
2476 if Base_Type (Opnd_Typ) = Ctyp then
2478 Operands (NN) := Opnd;
2479 Is_Fixed_Length (NN) := True;
2480 Fixed_Length (NN) := Uint_1;
2481 Result_May_Be_Null := False;
2483 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
2484 -- since we know that the result cannot be null).
2486 Opnd_Low_Bound (NN) :=
2487 Make_Attribute_Reference (Loc,
2488 Prefix => New_Reference_To (Istyp, Loc),
2489 Attribute_Name => Name_First);
2493 -- String literal case (can only occur for strings of course)
2495 elsif Nkind (Opnd) = N_String_Literal then
2496 Len := String_Literal_Length (Opnd_Typ);
2499 Result_May_Be_Null := False;
2502 -- Capture last operand high bound if result could be null
2504 if J = N and then Result_May_Be_Null then
2505 Last_Opnd_High_Bound :=
2508 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ)),
2509 Right_Opnd => Make_Integer_Literal (Loc, 1));
2512 -- Skip null string literal
2514 if J < N and then Len = 0 then
2519 Operands (NN) := Opnd;
2520 Is_Fixed_Length (NN) := True;
2522 -- Set length and bounds
2524 Fixed_Length (NN) := Len;
2526 Opnd_Low_Bound (NN) :=
2527 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ));
2534 -- Check constrained case with known bounds
2536 if Is_Constrained (Opnd_Typ) then
2538 Index : constant Node_Id := First_Index (Opnd_Typ);
2539 Indx_Typ : constant Entity_Id := Etype (Index);
2540 Lo : constant Node_Id := Type_Low_Bound (Indx_Typ);
2541 Hi : constant Node_Id := Type_High_Bound (Indx_Typ);
2544 -- Fixed length constrained array type with known at compile
2545 -- time bounds is last case of fixed length operand.
2547 if Compile_Time_Known_Value (Lo)
2549 Compile_Time_Known_Value (Hi)
2552 Loval : constant Uint := Expr_Value (Lo);
2553 Hival : constant Uint := Expr_Value (Hi);
2554 Len : constant Uint :=
2555 UI_Max (Hival - Loval + 1, Uint_0);
2559 Result_May_Be_Null := False;
2562 -- Capture last operand bound if result could be null
2564 if J = N and then Result_May_Be_Null then
2565 Last_Opnd_High_Bound :=
2567 Make_Integer_Literal (Loc,
2568 Intval => Expr_Value (Hi)));
2571 -- Exclude null length case unless last operand
2573 if J < N and then Len = 0 then
2578 Operands (NN) := Opnd;
2579 Is_Fixed_Length (NN) := True;
2580 Fixed_Length (NN) := Len;
2582 Opnd_Low_Bound (NN) := To_Ityp (
2583 Make_Integer_Literal (Loc,
2584 Intval => Expr_Value (Lo)));
2592 -- All cases where the length is not known at compile time, or the
2593 -- special case of an operand which is known to be null but has a
2594 -- lower bound other than 1 or is other than a string type.
2599 -- Capture operand bounds
2601 Opnd_Low_Bound (NN) :=
2602 Make_Attribute_Reference (Loc,
2604 Duplicate_Subexpr (Opnd, Name_Req => True),
2605 Attribute_Name => Name_First);
2607 if J = N and Result_May_Be_Null then
2608 Last_Opnd_High_Bound :=
2610 Make_Attribute_Reference (Loc,
2612 Duplicate_Subexpr (Opnd, Name_Req => True),
2613 Attribute_Name => Name_Last));
2616 -- Capture length of operand in entity
2618 Operands (NN) := Opnd;
2619 Is_Fixed_Length (NN) := False;
2622 Make_Defining_Identifier (Loc,
2623 Chars => New_Internal_Name ('L'));
2626 Make_Object_Declaration (Loc,
2627 Defining_Identifier => Var_Length (NN),
2628 Constant_Present => True,
2630 Object_Definition =>
2631 New_Occurrence_Of (Artyp, Loc),
2634 Make_Attribute_Reference (Loc,
2636 Duplicate_Subexpr (Opnd, Name_Req => True),
2637 Attribute_Name => Name_Length)));
2641 -- Set next entry in aggregate length array
2643 -- For first entry, make either integer literal for fixed length
2644 -- or a reference to the saved length for variable length.
2647 if Is_Fixed_Length (1) then
2649 Make_Integer_Literal (Loc,
2650 Intval => Fixed_Length (1));
2653 New_Reference_To (Var_Length (1), Loc);
2656 -- If entry is fixed length and only fixed lengths so far, make
2657 -- appropriate new integer literal adding new length.
2659 elsif Is_Fixed_Length (NN)
2660 and then Nkind (Aggr_Length (NN - 1)) = N_Integer_Literal
2663 Make_Integer_Literal (Loc,
2664 Intval => Fixed_Length (NN) + Intval (Aggr_Length (NN - 1)));
2666 -- All other cases, construct an addition node for the length and
2667 -- create an entity initialized to this length.
2671 Make_Defining_Identifier (Loc,
2672 Chars => New_Internal_Name ('L'));
2674 if Is_Fixed_Length (NN) then
2675 Clen := Make_Integer_Literal (Loc, Fixed_Length (NN));
2677 Clen := New_Reference_To (Var_Length (NN), Loc);
2681 Make_Object_Declaration (Loc,
2682 Defining_Identifier => Ent,
2683 Constant_Present => True,
2685 Object_Definition =>
2686 New_Occurrence_Of (Artyp, Loc),
2690 Left_Opnd => New_Copy (Aggr_Length (NN - 1)),
2691 Right_Opnd => Clen)));
2693 Aggr_Length (NN) := Make_Identifier (Loc, Chars => Chars (Ent));
2700 -- If we have only skipped null operands, return the last operand
2707 -- If we have only one non-null operand, return it and we are done.
2708 -- There is one case in which this cannot be done, and that is when
2709 -- the sole operand is of the element type, in which case it must be
2710 -- converted to an array, and the easiest way of doing that is to go
2711 -- through the normal general circuit.
2714 and then Base_Type (Etype (Operands (1))) /= Ctyp
2716 Result := Operands (1);
2720 -- Cases where we have a real concatenation
2722 -- Next step is to find the low bound for the result array that we
2723 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
2725 -- If the ultimate ancestor of the index subtype is a constrained array
2726 -- definition, then the lower bound is that of the index subtype as
2727 -- specified by (RM 4.5.3(6)).
2729 -- The right test here is to go to the root type, and then the ultimate
2730 -- ancestor is the first subtype of this root type.
2732 if Is_Constrained (First_Subtype (Root_Type (Atyp))) then
2734 Make_Attribute_Reference (Loc,
2736 New_Occurrence_Of (First_Subtype (Root_Type (Atyp)), Loc),
2737 Attribute_Name => Name_First);
2739 -- If the first operand in the list has known length we know that
2740 -- the lower bound of the result is the lower bound of this operand.
2742 elsif Is_Fixed_Length (1) then
2743 Low_Bound := Opnd_Low_Bound (1);
2745 -- OK, we don't know the lower bound, we have to build a horrible
2746 -- expression actions node of the form
2748 -- if Cond1'Length /= 0 then
2751 -- if Opnd2'Length /= 0 then
2756 -- The nesting ends either when we hit an operand whose length is known
2757 -- at compile time, or on reaching the last operand, whose low bound we
2758 -- take unconditionally whether or not it is null. It's easiest to do
2759 -- this with a recursive procedure:
2763 function Get_Known_Bound (J : Nat) return Node_Id;
2764 -- Returns the lower bound determined by operands J .. NN
2766 ---------------------
2767 -- Get_Known_Bound --
2768 ---------------------
2770 function Get_Known_Bound (J : Nat) return Node_Id is
2772 if Is_Fixed_Length (J) or else J = NN then
2773 return New_Copy (Opnd_Low_Bound (J));
2777 Make_Conditional_Expression (Loc,
2778 Expressions => New_List (
2781 Left_Opnd => New_Reference_To (Var_Length (J), Loc),
2782 Right_Opnd => Make_Integer_Literal (Loc, 0)),
2784 New_Copy (Opnd_Low_Bound (J)),
2785 Get_Known_Bound (J + 1)));
2787 end Get_Known_Bound;
2791 Make_Defining_Identifier (Loc, Chars => New_Internal_Name ('L'));
2794 Make_Object_Declaration (Loc,
2795 Defining_Identifier => Ent,
2796 Constant_Present => True,
2797 Object_Definition => New_Occurrence_Of (Ityp, Loc),
2798 Expression => Get_Known_Bound (1)));
2800 Low_Bound := New_Reference_To (Ent, Loc);
2804 -- Now we can safely compute the upper bound, normally
2805 -- Low_Bound + Length - 1.
2810 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2812 Make_Op_Subtract (Loc,
2813 Left_Opnd => New_Copy (Aggr_Length (NN)),
2814 Right_Opnd => Make_Artyp_Literal (1))));
2816 -- Note that calculation of the high bound may cause overflow in some
2817 -- very weird cases, so in the general case we need an overflow check on
2818 -- the high bound. We can avoid this for the common case of string types
2819 -- and other types whose index is Positive, since we chose a wider range
2820 -- for the arithmetic type.
2822 if Istyp /= Standard_Positive then
2823 Activate_Overflow_Check (High_Bound);
2826 -- Handle the exceptional case where the result is null, in which case
2827 -- case the bounds come from the last operand (so that we get the proper
2828 -- bounds if the last operand is super-flat).
2830 if Result_May_Be_Null then
2832 Make_Conditional_Expression (Loc,
2833 Expressions => New_List (
2835 Left_Opnd => New_Copy (Aggr_Length (NN)),
2836 Right_Opnd => Make_Artyp_Literal (0)),
2837 Last_Opnd_High_Bound,
2841 -- Here is where we insert the saved up actions
2843 Insert_Actions (Cnode, Actions, Suppress => All_Checks);
2845 -- Now we construct an array object with appropriate bounds
2848 Make_Defining_Identifier (Loc,
2849 Chars => New_Internal_Name ('S'));
2851 -- If the bound is statically known to be out of range, we do not want
2852 -- to abort, we want a warning and a runtime constraint error. Note that
2853 -- we have arranged that the result will not be treated as a static
2854 -- constant, so we won't get an illegality during this insertion.
2856 Insert_Action (Cnode,
2857 Make_Object_Declaration (Loc,
2858 Defining_Identifier => Ent,
2859 Object_Definition =>
2860 Make_Subtype_Indication (Loc,
2861 Subtype_Mark => New_Occurrence_Of (Atyp, Loc),
2863 Make_Index_Or_Discriminant_Constraint (Loc,
2864 Constraints => New_List (
2866 Low_Bound => Low_Bound,
2867 High_Bound => High_Bound))))),
2868 Suppress => All_Checks);
2870 -- If the result of the concatenation appears as the initializing
2871 -- expression of an object declaration, we can just rename the
2872 -- result, rather than copying it.
2874 Set_OK_To_Rename (Ent);
2876 -- Catch the static out of range case now
2878 if Raises_Constraint_Error (High_Bound) then
2879 raise Concatenation_Error;
2882 -- Now we will generate the assignments to do the actual concatenation
2884 -- There is one case in which we will not do this, namely when all the
2885 -- following conditions are met:
2887 -- The result type is Standard.String
2889 -- There are nine or fewer retained (non-null) operands
2891 -- The optimization level is -O0
2893 -- The corresponding System.Concat_n.Str_Concat_n routine is
2894 -- available in the run time.
2896 -- The debug flag gnatd.c is not set
2898 -- If all these conditions are met then we generate a call to the
2899 -- relevant concatenation routine. The purpose of this is to avoid
2900 -- undesirable code bloat at -O0.
2902 if Atyp = Standard_String
2903 and then NN in 2 .. 9
2904 and then (Opt.Optimization_Level = 0 or else Debug_Flag_Dot_CC)
2905 and then not Debug_Flag_Dot_C
2908 RR : constant array (Nat range 2 .. 9) of RE_Id :=
2919 if RTE_Available (RR (NN)) then
2921 Opnds : constant List_Id :=
2922 New_List (New_Occurrence_Of (Ent, Loc));
2925 for J in 1 .. NN loop
2926 if Is_List_Member (Operands (J)) then
2927 Remove (Operands (J));
2930 if Base_Type (Etype (Operands (J))) = Ctyp then
2932 Make_Aggregate (Loc,
2933 Component_Associations => New_List (
2934 Make_Component_Association (Loc,
2935 Choices => New_List (
2936 Make_Integer_Literal (Loc, 1)),
2937 Expression => Operands (J)))));
2940 Append_To (Opnds, Operands (J));
2944 Insert_Action (Cnode,
2945 Make_Procedure_Call_Statement (Loc,
2946 Name => New_Reference_To (RTE (RR (NN)), Loc),
2947 Parameter_Associations => Opnds));
2949 Result := New_Reference_To (Ent, Loc);
2956 -- Not special case so generate the assignments
2958 Known_Non_Null_Operand_Seen := False;
2960 for J in 1 .. NN loop
2962 Lo : constant Node_Id :=
2964 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2965 Right_Opnd => Aggr_Length (J - 1));
2967 Hi : constant Node_Id :=
2969 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
2971 Make_Op_Subtract (Loc,
2972 Left_Opnd => Aggr_Length (J),
2973 Right_Opnd => Make_Artyp_Literal (1)));
2976 -- Singleton case, simple assignment
2978 if Base_Type (Etype (Operands (J))) = Ctyp then
2979 Known_Non_Null_Operand_Seen := True;
2980 Insert_Action (Cnode,
2981 Make_Assignment_Statement (Loc,
2983 Make_Indexed_Component (Loc,
2984 Prefix => New_Occurrence_Of (Ent, Loc),
2985 Expressions => New_List (To_Ityp (Lo))),
2986 Expression => Operands (J)),
2987 Suppress => All_Checks);
2989 -- Array case, slice assignment, skipped when argument is fixed
2990 -- length and known to be null.
2992 elsif (not Is_Fixed_Length (J)) or else (Fixed_Length (J) > 0) then
2995 Make_Assignment_Statement (Loc,
2999 New_Occurrence_Of (Ent, Loc),
3002 Low_Bound => To_Ityp (Lo),
3003 High_Bound => To_Ityp (Hi))),
3004 Expression => Operands (J));
3006 if Is_Fixed_Length (J) then
3007 Known_Non_Null_Operand_Seen := True;
3009 elsif not Known_Non_Null_Operand_Seen then
3011 -- Here if operand length is not statically known and no
3012 -- operand known to be non-null has been processed yet.
3013 -- If operand length is 0, we do not need to perform the
3014 -- assignment, and we must avoid the evaluation of the
3015 -- high bound of the slice, since it may underflow if the
3016 -- low bound is Ityp'First.
3019 Make_Implicit_If_Statement (Cnode,
3023 New_Occurrence_Of (Var_Length (J), Loc),
3024 Right_Opnd => Make_Integer_Literal (Loc, 0)),
3029 Insert_Action (Cnode, Assign, Suppress => All_Checks);
3035 -- Finally we build the result, which is a reference to the array object
3037 Result := New_Reference_To (Ent, Loc);
3040 Rewrite (Cnode, Result);
3041 Analyze_And_Resolve (Cnode, Atyp);
3044 when Concatenation_Error =>
3046 -- Kill warning generated for the declaration of the static out of
3047 -- range high bound, and instead generate a Constraint_Error with
3048 -- an appropriate specific message.
3050 Kill_Dead_Code (Declaration_Node (Entity (High_Bound)));
3051 Apply_Compile_Time_Constraint_Error
3053 Msg => "concatenation result upper bound out of range?",
3054 Reason => CE_Range_Check_Failed);
3055 -- Set_Etype (Cnode, Atyp);
3056 end Expand_Concatenate;
3058 ------------------------
3059 -- Expand_N_Allocator --
3060 ------------------------
3062 procedure Expand_N_Allocator (N : Node_Id) is
3063 PtrT : constant Entity_Id := Etype (N);
3064 Dtyp : constant Entity_Id := Available_View (Designated_Type (PtrT));
3065 Etyp : constant Entity_Id := Etype (Expression (N));
3066 Loc : constant Source_Ptr := Sloc (N);
3071 procedure Complete_Coextension_Finalization;
3072 -- Generate finalization calls for all nested coextensions of N. This
3073 -- routine may allocate list controllers if necessary.
3075 procedure Rewrite_Coextension (N : Node_Id);
3076 -- Static coextensions have the same lifetime as the entity they
3077 -- constrain. Such occurrences can be rewritten as aliased objects
3078 -- and their unrestricted access used instead of the coextension.
3080 function Size_In_Storage_Elements (E : Entity_Id) return Node_Id;
3081 -- Given a constrained array type E, returns a node representing the
3082 -- code to compute the size in storage elements for the given type.
3083 -- This is done without using the attribute (which malfunctions for
3086 ---------------------------------------
3087 -- Complete_Coextension_Finalization --
3088 ---------------------------------------
3090 procedure Complete_Coextension_Finalization is
3092 Coext_Elmt : Elmt_Id;
3096 function Inside_A_Return_Statement (N : Node_Id) return Boolean;
3097 -- Determine whether node N is part of a return statement
3099 function Needs_Initialization_Call (N : Node_Id) return Boolean;
3100 -- Determine whether node N is a subtype indicator allocator which
3101 -- acts a coextension. Such coextensions need initialization.
3103 -------------------------------
3104 -- Inside_A_Return_Statement --
3105 -------------------------------
3107 function Inside_A_Return_Statement (N : Node_Id) return Boolean is
3112 while Present (P) loop
3114 (P, N_Extended_Return_Statement, N_Simple_Return_Statement)
3118 -- Stop the traversal when we reach a subprogram body
3120 elsif Nkind (P) = N_Subprogram_Body then
3128 end Inside_A_Return_Statement;
3130 -------------------------------
3131 -- Needs_Initialization_Call --
3132 -------------------------------
3134 function Needs_Initialization_Call (N : Node_Id) return Boolean is
3138 if Nkind (N) = N_Explicit_Dereference
3139 and then Nkind (Prefix (N)) = N_Identifier
3140 and then Nkind (Parent (Entity (Prefix (N)))) =
3141 N_Object_Declaration
3143 Obj_Decl := Parent (Entity (Prefix (N)));
3146 Present (Expression (Obj_Decl))
3147 and then Nkind (Expression (Obj_Decl)) = N_Allocator
3148 and then Nkind (Expression (Expression (Obj_Decl))) /=
3149 N_Qualified_Expression;
3153 end Needs_Initialization_Call;
3155 -- Start of processing for Complete_Coextension_Finalization
3158 -- When a coextension root is inside a return statement, we need to
3159 -- use the finalization chain of the function's scope. This does not
3160 -- apply for controlled named access types because in those cases we
3161 -- can use the finalization chain of the type itself.
3163 if Inside_A_Return_Statement (N)
3165 (Ekind (PtrT) = E_Anonymous_Access_Type
3167 (Ekind (PtrT) = E_Access_Type
3168 and then No (Associated_Final_Chain (PtrT))))
3172 Outer_S : Entity_Id;
3173 S : Entity_Id := Current_Scope;
3176 while Present (S) and then S /= Standard_Standard loop
3177 if Ekind (S) = E_Function then
3178 Outer_S := Scope (S);
3180 -- Retrieve the declaration of the body
3185 (Corresponding_Body (Parent (Parent (S)))));
3192 -- Push the scope of the function body since we are inserting
3193 -- the list before the body, but we are currently in the body
3194 -- itself. Override the finalization list of PtrT since the
3195 -- finalization context is now different.
3197 Push_Scope (Outer_S);
3198 Build_Final_List (Decl, PtrT);
3202 -- The root allocator may not be controlled, but it still needs a
3203 -- finalization list for all nested coextensions.
3205 elsif No (Associated_Final_Chain (PtrT)) then
3206 Build_Final_List (N, PtrT);
3210 Make_Selected_Component (Loc,
3212 New_Reference_To (Associated_Final_Chain (PtrT), Loc),
3214 Make_Identifier (Loc, Name_F));
3216 Coext_Elmt := First_Elmt (Coextensions (N));
3217 while Present (Coext_Elmt) loop
3218 Coext := Node (Coext_Elmt);
3223 if Nkind (Coext) = N_Identifier then
3225 Make_Unchecked_Type_Conversion (Loc,
3226 Subtype_Mark => New_Reference_To (Etype (Coext), Loc),
3228 Make_Explicit_Dereference (Loc,
3229 Prefix => New_Copy_Tree (Coext)));
3231 Ref := New_Copy_Tree (Coext);
3234 -- No initialization call if not allowed
3236 Check_Restriction (No_Default_Initialization, N);
3238 if not Restriction_Active (No_Default_Initialization) then
3242 -- attach_to_final_list (Ref, Flist, 2)
3244 if Needs_Initialization_Call (Coext) then
3248 Typ => Etype (Coext),
3250 With_Attach => Make_Integer_Literal (Loc, Uint_2)));
3253 -- attach_to_final_list (Ref, Flist, 2)
3259 Flist_Ref => New_Copy_Tree (Flist),
3260 With_Attach => Make_Integer_Literal (Loc, Uint_2)));
3264 Next_Elmt (Coext_Elmt);
3266 end Complete_Coextension_Finalization;
3268 -------------------------
3269 -- Rewrite_Coextension --
3270 -------------------------
3272 procedure Rewrite_Coextension (N : Node_Id) is
3273 Temp : constant Node_Id :=
3274 Make_Defining_Identifier (Loc,
3275 New_Internal_Name ('C'));
3278 -- Cnn : aliased Etyp;
3280 Decl : constant Node_Id :=
3281 Make_Object_Declaration (Loc,
3282 Defining_Identifier => Temp,
3283 Aliased_Present => True,
3284 Object_Definition =>
3285 New_Occurrence_Of (Etyp, Loc));
3289 if Nkind (Expression (N)) = N_Qualified_Expression then
3290 Set_Expression (Decl, Expression (Expression (N)));
3293 -- Find the proper insertion node for the declaration
3296 while Present (Nod) loop
3297 exit when Nkind (Nod) in N_Statement_Other_Than_Procedure_Call
3298 or else Nkind (Nod) = N_Procedure_Call_Statement
3299 or else Nkind (Nod) in N_Declaration;
3300 Nod := Parent (Nod);
3303 Insert_Before (Nod, Decl);
3307 Make_Attribute_Reference (Loc,
3308 Prefix => New_Occurrence_Of (Temp, Loc),
3309 Attribute_Name => Name_Unrestricted_Access));
3311 Analyze_And_Resolve (N, PtrT);
3312 end Rewrite_Coextension;
3314 ------------------------------
3315 -- Size_In_Storage_Elements --
3316 ------------------------------
3318 function Size_In_Storage_Elements (E : Entity_Id) return Node_Id is
3320 -- Logically this just returns E'Max_Size_In_Storage_Elements.
3321 -- However, the reason for the existence of this function is
3322 -- to construct a test for sizes too large, which means near the
3323 -- 32-bit limit on a 32-bit machine, and precisely the trouble
3324 -- is that we get overflows when sizes are greater than 2**31.
3326 -- So what we end up doing for array types is to use the expression:
3328 -- number-of-elements * component_type'Max_Size_In_Storage_Elements
3330 -- which avoids this problem. All this is a big bogus, but it does
3331 -- mean we catch common cases of trying to allocate arrays that
3332 -- are too large, and which in the absence of a check results in
3333 -- undetected chaos ???
3340 for J in 1 .. Number_Dimensions (E) loop
3342 Make_Attribute_Reference (Loc,
3343 Prefix => New_Occurrence_Of (E, Loc),
3344 Attribute_Name => Name_Length,
3345 Expressions => New_List (
3346 Make_Integer_Literal (Loc, J)));
3353 Make_Op_Multiply (Loc,
3360 Make_Op_Multiply (Loc,
3363 Make_Attribute_Reference (Loc,
3364 Prefix => New_Occurrence_Of (Component_Type (E), Loc),
3365 Attribute_Name => Name_Max_Size_In_Storage_Elements));
3367 end Size_In_Storage_Elements;
3369 -- Start of processing for Expand_N_Allocator
3372 -- RM E.2.3(22). We enforce that the expected type of an allocator
3373 -- shall not be a remote access-to-class-wide-limited-private type
3375 -- Why is this being done at expansion time, seems clearly wrong ???
3377 Validate_Remote_Access_To_Class_Wide_Type (N);
3379 -- Set the Storage Pool
3381 Set_Storage_Pool (N, Associated_Storage_Pool (Root_Type (PtrT)));
3383 if Present (Storage_Pool (N)) then
3384 if Is_RTE (Storage_Pool (N), RE_SS_Pool) then
3385 if VM_Target = No_VM then
3386 Set_Procedure_To_Call (N, RTE (RE_SS_Allocate));
3389 elsif Is_Class_Wide_Type (Etype (Storage_Pool (N))) then
3390 Set_Procedure_To_Call (N, RTE (RE_Allocate_Any));
3393 Set_Procedure_To_Call (N,
3394 Find_Prim_Op (Etype (Storage_Pool (N)), Name_Allocate));
3398 -- Under certain circumstances we can replace an allocator by an access
3399 -- to statically allocated storage. The conditions, as noted in AARM
3400 -- 3.10 (10c) are as follows:
3402 -- Size and initial value is known at compile time
3403 -- Access type is access-to-constant
3405 -- The allocator is not part of a constraint on a record component,
3406 -- because in that case the inserted actions are delayed until the
3407 -- record declaration is fully analyzed, which is too late for the
3408 -- analysis of the rewritten allocator.
3410 if Is_Access_Constant (PtrT)
3411 and then Nkind (Expression (N)) = N_Qualified_Expression
3412 and then Compile_Time_Known_Value (Expression (Expression (N)))
3413 and then Size_Known_At_Compile_Time (Etype (Expression
3415 and then not Is_Record_Type (Current_Scope)
3417 -- Here we can do the optimization. For the allocator
3421 -- We insert an object declaration
3423 -- Tnn : aliased x := y;
3425 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
3426 -- marked as requiring static allocation.
3429 Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
3431 Desig := Subtype_Mark (Expression (N));
3433 -- If context is constrained, use constrained subtype directly,
3434 -- so that the constant is not labelled as having a nominally
3435 -- unconstrained subtype.
3437 if Entity (Desig) = Base_Type (Dtyp) then
3438 Desig := New_Occurrence_Of (Dtyp, Loc);
3442 Make_Object_Declaration (Loc,
3443 Defining_Identifier => Temp,
3444 Aliased_Present => True,
3445 Constant_Present => Is_Access_Constant (PtrT),
3446 Object_Definition => Desig,
3447 Expression => Expression (Expression (N))));
3450 Make_Attribute_Reference (Loc,
3451 Prefix => New_Occurrence_Of (Temp, Loc),
3452 Attribute_Name => Name_Unrestricted_Access));
3454 Analyze_And_Resolve (N, PtrT);
3456 -- We set the variable as statically allocated, since we don't want
3457 -- it going on the stack of the current procedure!
3459 Set_Is_Statically_Allocated (Temp);
3463 -- Same if the allocator is an access discriminant for a local object:
3464 -- instead of an allocator we create a local value and constrain the
3465 -- the enclosing object with the corresponding access attribute.
3467 if Is_Static_Coextension (N) then
3468 Rewrite_Coextension (N);
3472 -- The current allocator creates an object which may contain nested
3473 -- coextensions. Use the current allocator's finalization list to
3474 -- generate finalization call for all nested coextensions.
3476 if Is_Coextension_Root (N) then
3477 Complete_Coextension_Finalization;
3480 -- Check for size too large, we do this because the back end misses
3481 -- proper checks here and can generate rubbish allocation calls when
3482 -- we are near the limit. We only do this for the 32-bit address case
3483 -- since that is from a practical point of view where we see a problem.
3485 if System_Address_Size = 32
3486 and then not Storage_Checks_Suppressed (PtrT)
3487 and then not Storage_Checks_Suppressed (Dtyp)
3488 and then not Storage_Checks_Suppressed (Etyp)
3490 -- The check we want to generate should look like
3492 -- if Etyp'Max_Size_In_Storage_Elements > 3.5 gigabytes then
3493 -- raise Storage_Error;
3496 -- where 3.5 gigabytes is a constant large enough to accomodate any
3497 -- reasonable request for. But we can't do it this way because at
3498 -- least at the moment we don't compute this attribute right, and
3499 -- can silently give wrong results when the result gets large. Since
3500 -- this is all about large results, that's bad, so instead we only
3501 -- apply the check for constrained arrays, and manually compute the
3502 -- value of the attribute ???
3504 if Is_Array_Type (Etyp) and then Is_Constrained (Etyp) then
3506 Make_Raise_Storage_Error (Loc,
3509 Left_Opnd => Size_In_Storage_Elements (Etyp),
3511 Make_Integer_Literal (Loc,
3512 Intval => Uint_7 * (Uint_2 ** 29))),
3513 Reason => SE_Object_Too_Large));
3517 -- Handle case of qualified expression (other than optimization above)
3518 -- First apply constraint checks, because the bounds or discriminants
3519 -- in the aggregate might not match the subtype mark in the allocator.
3521 if Nkind (Expression (N)) = N_Qualified_Expression then
3522 Apply_Constraint_Check
3523 (Expression (Expression (N)), Etype (Expression (N)));
3525 Expand_Allocator_Expression (N);
3529 -- If the allocator is for a type which requires initialization, and
3530 -- there is no initial value (i.e. operand is a subtype indication
3531 -- rather than a qualified expression), then we must generate a call to
3532 -- the initialization routine using an expressions action node:
3534 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
3536 -- Here ptr_T is the pointer type for the allocator, and T is the
3537 -- subtype of the allocator. A special case arises if the designated
3538 -- type of the access type is a task or contains tasks. In this case
3539 -- the call to Init (Temp.all ...) is replaced by code that ensures
3540 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
3541 -- for details). In addition, if the type T is a task T, then the
3542 -- first argument to Init must be converted to the task record type.
3545 T : constant Entity_Id := Entity (Expression (N));
3553 Temp_Decl : Node_Id;
3554 Temp_Type : Entity_Id;
3555 Attach_Level : Uint;
3558 if No_Initialization (N) then
3561 -- Case of no initialization procedure present
3563 elsif not Has_Non_Null_Base_Init_Proc (T) then
3565 -- Case of simple initialization required
3567 if Needs_Simple_Initialization (T) then
3568 Check_Restriction (No_Default_Initialization, N);
3569 Rewrite (Expression (N),
3570 Make_Qualified_Expression (Loc,
3571 Subtype_Mark => New_Occurrence_Of (T, Loc),
3572 Expression => Get_Simple_Init_Val (T, N)));
3574 Analyze_And_Resolve (Expression (Expression (N)), T);
3575 Analyze_And_Resolve (Expression (N), T);
3576 Set_Paren_Count (Expression (Expression (N)), 1);
3577 Expand_N_Allocator (N);
3579 -- No initialization required
3585 -- Case of initialization procedure present, must be called
3588 Check_Restriction (No_Default_Initialization, N);
3590 if not Restriction_Active (No_Default_Initialization) then
3591 Init := Base_Init_Proc (T);
3593 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
3595 -- Construct argument list for the initialization routine call
3598 Make_Explicit_Dereference (Loc,
3599 Prefix => New_Reference_To (Temp, Loc));
3600 Set_Assignment_OK (Arg1);
3603 -- The initialization procedure expects a specific type. if the
3604 -- context is access to class wide, indicate that the object
3605 -- being allocated has the right specific type.
3607 if Is_Class_Wide_Type (Dtyp) then
3608 Arg1 := Unchecked_Convert_To (T, Arg1);
3611 -- If designated type is a concurrent type or if it is private
3612 -- type whose definition is a concurrent type, the first
3613 -- argument in the Init routine has to be unchecked conversion
3614 -- to the corresponding record type. If the designated type is
3615 -- a derived type, we also convert the argument to its root
3618 if Is_Concurrent_Type (T) then
3620 Unchecked_Convert_To (Corresponding_Record_Type (T), Arg1);
3622 elsif Is_Private_Type (T)
3623 and then Present (Full_View (T))
3624 and then Is_Concurrent_Type (Full_View (T))
3627 Unchecked_Convert_To
3628 (Corresponding_Record_Type (Full_View (T)), Arg1);
3630 elsif Etype (First_Formal (Init)) /= Base_Type (T) then
3632 Ftyp : constant Entity_Id := Etype (First_Formal (Init));
3634 Arg1 := OK_Convert_To (Etype (Ftyp), Arg1);
3635 Set_Etype (Arg1, Ftyp);
3639 Args := New_List (Arg1);
3641 -- For the task case, pass the Master_Id of the access type as
3642 -- the value of the _Master parameter, and _Chain as the value
3643 -- of the _Chain parameter (_Chain will be defined as part of
3644 -- the generated code for the allocator).
3646 -- In Ada 2005, the context may be a function that returns an
3647 -- anonymous access type. In that case the Master_Id has been
3648 -- created when expanding the function declaration.
3650 if Has_Task (T) then
3651 if No (Master_Id (Base_Type (PtrT))) then
3653 -- If we have a non-library level task with restriction
3654 -- No_Task_Hierarchy set, then no point in expanding.
3656 if not Is_Library_Level_Entity (T)
3657 and then Restriction_Active (No_Task_Hierarchy)
3662 -- The designated type was an incomplete type, and the
3663 -- access type did not get expanded. Salvage it now.
3665 pragma Assert (Present (Parent (Base_Type (PtrT))));
3666 Expand_N_Full_Type_Declaration
3667 (Parent (Base_Type (PtrT)));
3670 -- If the context of the allocator is a declaration or an
3671 -- assignment, we can generate a meaningful image for it,
3672 -- even though subsequent assignments might remove the
3673 -- connection between task and entity. We build this image
3674 -- when the left-hand side is a simple variable, a simple
3675 -- indexed assignment or a simple selected component.
3677 if Nkind (Parent (N)) = N_Assignment_Statement then
3679 Nam : constant Node_Id := Name (Parent (N));
3682 if Is_Entity_Name (Nam) then
3684 Build_Task_Image_Decls
3687 (Entity (Nam), Sloc (Nam)), T);
3690 (Nam, N_Indexed_Component, N_Selected_Component)
3691 and then Is_Entity_Name (Prefix (Nam))
3694 Build_Task_Image_Decls
3695 (Loc, Nam, Etype (Prefix (Nam)));
3697 Decls := Build_Task_Image_Decls (Loc, T, T);
3701 elsif Nkind (Parent (N)) = N_Object_Declaration then
3703 Build_Task_Image_Decls
3704 (Loc, Defining_Identifier (Parent (N)), T);
3707 Decls := Build_Task_Image_Decls (Loc, T, T);
3712 (Master_Id (Base_Type (Root_Type (PtrT))), Loc));
3713 Append_To (Args, Make_Identifier (Loc, Name_uChain));
3715 Decl := Last (Decls);
3717 New_Occurrence_Of (Defining_Identifier (Decl), Loc));
3719 -- Has_Task is false, Decls not used
3725 -- Add discriminants if discriminated type
3728 Dis : Boolean := False;
3732 if Has_Discriminants (T) then
3736 elsif Is_Private_Type (T)
3737 and then Present (Full_View (T))
3738 and then Has_Discriminants (Full_View (T))
3741 Typ := Full_View (T);
3746 -- If the allocated object will be constrained by the
3747 -- default values for discriminants, then build a subtype
3748 -- with those defaults, and change the allocated subtype
3749 -- to that. Note that this happens in fewer cases in Ada
3752 if not Is_Constrained (Typ)
3753 and then Present (Discriminant_Default_Value
3754 (First_Discriminant (Typ)))
3755 and then (Ada_Version < Ada_05
3757 not Has_Constrained_Partial_View (Typ))
3759 Typ := Build_Default_Subtype (Typ, N);
3760 Set_Expression (N, New_Reference_To (Typ, Loc));
3763 Discr := First_Elmt (Discriminant_Constraint (Typ));
3764 while Present (Discr) loop
3765 Nod := Node (Discr);
3766 Append (New_Copy_Tree (Node (Discr)), Args);
3768 -- AI-416: when the discriminant constraint is an
3769 -- anonymous access type make sure an accessibility
3770 -- check is inserted if necessary (3.10.2(22.q/2))
3772 if Ada_Version >= Ada_05
3774 Ekind (Etype (Nod)) = E_Anonymous_Access_Type
3776 Apply_Accessibility_Check
3777 (Nod, Typ, Insert_Node => Nod);
3785 -- We set the allocator as analyzed so that when we analyze the
3786 -- expression actions node, we do not get an unwanted recursive
3787 -- expansion of the allocator expression.
3789 Set_Analyzed (N, True);
3790 Nod := Relocate_Node (N);
3792 -- Here is the transformation:
3794 -- output: Temp : constant ptr_T := new T;
3795 -- Init (Temp.all, ...);
3796 -- <CTRL> Attach_To_Final_List (Finalizable (Temp.all));
3797 -- <CTRL> Initialize (Finalizable (Temp.all));
3799 -- Here ptr_T is the pointer type for the allocator, and is the
3800 -- subtype of the allocator.
3803 Make_Object_Declaration (Loc,
3804 Defining_Identifier => Temp,
3805 Constant_Present => True,
3806 Object_Definition => New_Reference_To (Temp_Type, Loc),
3809 Set_Assignment_OK (Temp_Decl);
3810 Insert_Action (N, Temp_Decl, Suppress => All_Checks);
3812 -- If the designated type is a task type or contains tasks,
3813 -- create block to activate created tasks, and insert
3814 -- declaration for Task_Image variable ahead of call.
3816 if Has_Task (T) then
3818 L : constant List_Id := New_List;
3821 Build_Task_Allocate_Block (L, Nod, Args);
3823 Insert_List_Before (First (Declarations (Blk)), Decls);
3824 Insert_Actions (N, L);
3829 Make_Procedure_Call_Statement (Loc,
3830 Name => New_Reference_To (Init, Loc),
3831 Parameter_Associations => Args));
3834 if Needs_Finalization (T) then
3836 -- Postpone the generation of a finalization call for the
3837 -- current allocator if it acts as a coextension.
3839 if Is_Dynamic_Coextension (N) then
3840 if No (Coextensions (N)) then
3841 Set_Coextensions (N, New_Elmt_List);
3844 Append_Elmt (New_Copy_Tree (Arg1), Coextensions (N));
3848 Get_Allocator_Final_List (N, Base_Type (T), PtrT);
3850 -- Anonymous access types created for access parameters
3851 -- are attached to an explicitly constructed controller,
3852 -- which ensures that they can be finalized properly,
3853 -- even if their deallocation might not happen. The list
3854 -- associated with the controller is doubly-linked. For
3855 -- other anonymous access types, the object may end up
3856 -- on the global final list which is singly-linked.
3857 -- Work needed for access discriminants in Ada 2005 ???
3859 if Ekind (PtrT) = E_Anonymous_Access_Type then
3860 Attach_Level := Uint_1;
3862 Attach_Level := Uint_2;
3867 Ref => New_Copy_Tree (Arg1),
3870 With_Attach => Make_Integer_Literal (Loc,
3871 Intval => Attach_Level)));
3875 Rewrite (N, New_Reference_To (Temp, Loc));
3876 Analyze_And_Resolve (N, PtrT);
3881 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
3882 -- object that has been rewritten as a reference, we displace "this"
3883 -- to reference properly its secondary dispatch table.
3885 if Nkind (N) = N_Identifier
3886 and then Is_Interface (Dtyp)
3888 Displace_Allocator_Pointer (N);
3892 when RE_Not_Available =>
3894 end Expand_N_Allocator;
3896 -----------------------
3897 -- Expand_N_And_Then --
3898 -----------------------
3900 -- Expand into conditional expression if Actions present, and also deal
3901 -- with optimizing case of arguments being True or False.
3903 procedure Expand_N_And_Then (N : Node_Id) is
3904 Loc : constant Source_Ptr := Sloc (N);
3905 Typ : constant Entity_Id := Etype (N);
3906 Left : constant Node_Id := Left_Opnd (N);
3907 Right : constant Node_Id := Right_Opnd (N);
3911 -- Deal with non-standard booleans
3913 if Is_Boolean_Type (Typ) then
3914 Adjust_Condition (Left);
3915 Adjust_Condition (Right);
3916 Set_Etype (N, Standard_Boolean);
3919 -- Check for cases where left argument is known to be True or False
3921 if Compile_Time_Known_Value (Left) then
3923 -- If left argument is True, change (True and then Right) to Right.
3924 -- Any actions associated with Right will be executed unconditionally
3925 -- and can thus be inserted into the tree unconditionally.
3927 if Expr_Value_E (Left) = Standard_True then
3928 if Present (Actions (N)) then
3929 Insert_Actions (N, Actions (N));
3934 -- If left argument is False, change (False and then Right) to False.
3935 -- In this case we can forget the actions associated with Right,
3936 -- since they will never be executed.
3938 else pragma Assert (Expr_Value_E (Left) = Standard_False);
3939 Kill_Dead_Code (Right);
3940 Kill_Dead_Code (Actions (N));
3941 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
3944 Adjust_Result_Type (N, Typ);
3948 -- If Actions are present, we expand
3950 -- left and then right
3954 -- if left then right else false end
3956 -- with the actions becoming the Then_Actions of the conditional
3957 -- expression. This conditional expression is then further expanded
3958 -- (and will eventually disappear)
3960 if Present (Actions (N)) then
3961 Actlist := Actions (N);
3963 Make_Conditional_Expression (Loc,
3964 Expressions => New_List (
3967 New_Occurrence_Of (Standard_False, Loc))));
3969 -- If the right part of the expression is a function call then it can
3970 -- be part of the expansion of the predefined equality operator of a
3971 -- tagged type and we may need to adjust its SCIL dispatching node.
3974 and then Nkind (Right) = N_Function_Call
3976 Adjust_SCIL_Node (N, Right);
3979 Set_Then_Actions (N, Actlist);
3980 Analyze_And_Resolve (N, Standard_Boolean);
3981 Adjust_Result_Type (N, Typ);
3985 -- No actions present, check for cases of right argument True/False
3987 if Compile_Time_Known_Value (Right) then
3989 -- Change (Left and then True) to Left. Note that we know there are
3990 -- no actions associated with the True operand, since we just checked
3991 -- for this case above.
3993 if Expr_Value_E (Right) = Standard_True then
3996 -- Change (Left and then False) to False, making sure to preserve any
3997 -- side effects associated with the Left operand.
3999 else pragma Assert (Expr_Value_E (Right) = Standard_False);
4000 Remove_Side_Effects (Left);
4001 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
4005 Adjust_Result_Type (N, Typ);
4006 end Expand_N_And_Then;
4008 -------------------------------------
4009 -- Expand_N_Conditional_Expression --
4010 -------------------------------------
4012 -- Expand into expression actions if then/else actions present
4014 procedure Expand_N_Conditional_Expression (N : Node_Id) is
4015 Loc : constant Source_Ptr := Sloc (N);
4016 Cond : constant Node_Id := First (Expressions (N));
4017 Thenx : constant Node_Id := Next (Cond);
4018 Elsex : constant Node_Id := Next (Thenx);
4019 Typ : constant Entity_Id := Etype (N);
4028 -- If either then or else actions are present, then given:
4030 -- if cond then then-expr else else-expr end
4032 -- we insert the following sequence of actions (using Insert_Actions):
4037 -- Cnn := then-expr;
4043 -- and replace the conditional expression by a reference to Cnn
4045 -- If the type is limited or unconstrained, the above expansion is
4046 -- not legal, because it involves either an uninitialized object
4047 -- or an illegal assignment. Instead, we generate:
4049 -- type Ptr is access all Typ;
4053 -- Cnn := then-expr'Unrestricted_Access;
4056 -- Cnn := else-expr'Unrestricted_Access;
4059 -- and replace the conditional expresion by a reference to Cnn.all.
4061 if Is_By_Reference_Type (Typ) then
4062 Cnn := Make_Temporary (Loc, 'C', N);
4065 Make_Full_Type_Declaration (Loc,
4066 Defining_Identifier =>
4067 Make_Defining_Identifier (Loc, New_Internal_Name ('A')),
4069 Make_Access_To_Object_Definition (Loc,
4070 All_Present => True,
4071 Subtype_Indication =>
4072 New_Reference_To (Typ, Loc)));
4074 Insert_Action (N, P_Decl);
4077 Make_Object_Declaration (Loc,
4078 Defining_Identifier => Cnn,
4079 Object_Definition =>
4080 New_Occurrence_Of (Defining_Identifier (P_Decl), Loc));
4083 Make_Implicit_If_Statement (N,
4084 Condition => Relocate_Node (Cond),
4086 Then_Statements => New_List (
4087 Make_Assignment_Statement (Sloc (Thenx),
4088 Name => New_Occurrence_Of (Cnn, Sloc (Thenx)),
4090 Make_Attribute_Reference (Loc,
4091 Attribute_Name => Name_Unrestricted_Access,
4092 Prefix => Relocate_Node (Thenx)))),
4094 Else_Statements => New_List (
4095 Make_Assignment_Statement (Sloc (Elsex),
4096 Name => New_Occurrence_Of (Cnn, Sloc (Elsex)),
4098 Make_Attribute_Reference (Loc,
4099 Attribute_Name => Name_Unrestricted_Access,
4100 Prefix => Relocate_Node (Elsex)))));
4103 Make_Explicit_Dereference (Loc,
4104 Prefix => New_Occurrence_Of (Cnn, Loc));
4106 -- For other types, we only need to expand if there are other actions
4107 -- associated with either branch.
4109 elsif Present (Then_Actions (N)) or else Present (Else_Actions (N)) then
4110 Cnn := Make_Temporary (Loc, 'C', N);
4113 Make_Object_Declaration (Loc,
4114 Defining_Identifier => Cnn,
4115 Object_Definition => New_Occurrence_Of (Typ, Loc));
4118 Make_Implicit_If_Statement (N,
4119 Condition => Relocate_Node (Cond),
4121 Then_Statements => New_List (
4122 Make_Assignment_Statement (Sloc (Thenx),
4123 Name => New_Occurrence_Of (Cnn, Sloc (Thenx)),
4124 Expression => Relocate_Node (Thenx))),
4126 Else_Statements => New_List (
4127 Make_Assignment_Statement (Sloc (Elsex),
4128 Name => New_Occurrence_Of (Cnn, Sloc (Elsex)),
4129 Expression => Relocate_Node (Elsex))));
4131 Set_Assignment_OK (Name (First (Then_Statements (New_If))));
4132 Set_Assignment_OK (Name (First (Else_Statements (New_If))));
4134 New_N := New_Occurrence_Of (Cnn, Loc);
4137 -- No expansion needed, gigi handles it like a C conditional
4143 -- Move the SLOC of the parent If statement to the newly created one and
4144 -- change it to the SLOC of the expression which, after expansion, will
4145 -- correspond to what is being evaluated.
4147 if Present (Parent (N))
4148 and then Nkind (Parent (N)) = N_If_Statement
4150 Set_Sloc (New_If, Sloc (Parent (N)));
4151 Set_Sloc (Parent (N), Loc);
4154 -- Make sure Then_Actions and Else_Actions are appropriately moved
4155 -- to the new if statement.
4157 if Present (Then_Actions (N)) then
4159 (First (Then_Statements (New_If)), Then_Actions (N));
4162 if Present (Else_Actions (N)) then
4164 (First (Else_Statements (New_If)), Else_Actions (N));
4167 Insert_Action (N, Decl);
4168 Insert_Action (N, New_If);
4170 Analyze_And_Resolve (N, Typ);
4171 end Expand_N_Conditional_Expression;
4173 -----------------------------------
4174 -- Expand_N_Explicit_Dereference --
4175 -----------------------------------
4177 procedure Expand_N_Explicit_Dereference (N : Node_Id) is
4179 -- Insert explicit dereference call for the checked storage pool case
4181 Insert_Dereference_Action (Prefix (N));
4182 end Expand_N_Explicit_Dereference;
4188 procedure Expand_N_In (N : Node_Id) is
4189 Loc : constant Source_Ptr := Sloc (N);
4190 Rtyp : constant Entity_Id := Etype (N);
4191 Lop : constant Node_Id := Left_Opnd (N);
4192 Rop : constant Node_Id := Right_Opnd (N);
4193 Static : constant Boolean := Is_OK_Static_Expression (N);
4195 procedure Expand_Set_Membership;
4196 -- For each disjunct we create a simple equality or membership test.
4197 -- The whole membership is rewritten as a short-circuit disjunction.
4199 ---------------------------
4200 -- Expand_Set_Membership --
4201 ---------------------------
4203 procedure Expand_Set_Membership is
4207 function Make_Cond (Alt : Node_Id) return Node_Id;
4208 -- If the alternative is a subtype mark, create a simple membership
4209 -- test. Otherwise create an equality test for it.
4215 function Make_Cond (Alt : Node_Id) return Node_Id is
4217 L : constant Node_Id := New_Copy (Lop);
4218 R : constant Node_Id := Relocate_Node (Alt);
4221 if Is_Entity_Name (Alt)
4222 and then Is_Type (Entity (Alt))
4225 Make_In (Sloc (Alt),
4229 Cond := Make_Op_Eq (Sloc (Alt),
4237 -- Start of proessing for Expand_N_In
4240 Alt := Last (Alternatives (N));
4241 Res := Make_Cond (Alt);
4244 while Present (Alt) loop
4246 Make_Or_Else (Sloc (Alt),
4247 Left_Opnd => Make_Cond (Alt),
4253 Analyze_And_Resolve (N, Standard_Boolean);
4254 end Expand_Set_Membership;
4256 procedure Substitute_Valid_Check;
4257 -- Replaces node N by Lop'Valid. This is done when we have an explicit
4258 -- test for the left operand being in range of its subtype.
4260 ----------------------------
4261 -- Substitute_Valid_Check --
4262 ----------------------------
4264 procedure Substitute_Valid_Check is
4267 Make_Attribute_Reference (Loc,
4268 Prefix => Relocate_Node (Lop),
4269 Attribute_Name => Name_Valid));
4271 Analyze_And_Resolve (N, Rtyp);
4273 Error_Msg_N ("?explicit membership test may be optimized away", N);
4274 Error_Msg_N ("\?use ''Valid attribute instead", N);
4276 end Substitute_Valid_Check;
4278 -- Start of processing for Expand_N_In
4282 if Present (Alternatives (N)) then
4283 Remove_Side_Effects (Lop);
4284 Expand_Set_Membership;
4288 -- Check case of explicit test for an expression in range of its
4289 -- subtype. This is suspicious usage and we replace it with a 'Valid
4290 -- test and give a warning.
4292 if Is_Scalar_Type (Etype (Lop))
4293 and then Nkind (Rop) in N_Has_Entity
4294 and then Etype (Lop) = Entity (Rop)
4295 and then Comes_From_Source (N)
4296 and then VM_Target = No_VM
4298 Substitute_Valid_Check;
4302 -- Do validity check on operands
4304 if Validity_Checks_On and Validity_Check_Operands then
4305 Ensure_Valid (Left_Opnd (N));
4306 Validity_Check_Range (Right_Opnd (N));
4309 -- Case of explicit range
4311 if Nkind (Rop) = N_Range then
4313 Lo : constant Node_Id := Low_Bound (Rop);
4314 Hi : constant Node_Id := High_Bound (Rop);
4316 Ltyp : constant Entity_Id := Etype (Lop);
4318 Lo_Orig : constant Node_Id := Original_Node (Lo);
4319 Hi_Orig : constant Node_Id := Original_Node (Hi);
4321 Lcheck : Compare_Result;
4322 Ucheck : Compare_Result;
4324 Warn1 : constant Boolean :=
4325 Constant_Condition_Warnings
4326 and then Comes_From_Source (N)
4327 and then not In_Instance;
4328 -- This must be true for any of the optimization warnings, we
4329 -- clearly want to give them only for source with the flag on.
4330 -- We also skip these warnings in an instance since it may be
4331 -- the case that different instantiations have different ranges.
4333 Warn2 : constant Boolean :=
4335 and then Nkind (Original_Node (Rop)) = N_Range
4336 and then Is_Integer_Type (Etype (Lo));
4337 -- For the case where only one bound warning is elided, we also
4338 -- insist on an explicit range and an integer type. The reason is
4339 -- that the use of enumeration ranges including an end point is
4340 -- common, as is the use of a subtype name, one of whose bounds
4341 -- is the same as the type of the expression.
4344 -- If test is explicit x'first .. x'last, replace by valid check
4346 if Is_Scalar_Type (Ltyp)
4347 and then Nkind (Lo_Orig) = N_Attribute_Reference
4348 and then Attribute_Name (Lo_Orig) = Name_First
4349 and then Nkind (Prefix (Lo_Orig)) in N_Has_Entity
4350 and then Entity (Prefix (Lo_Orig)) = Ltyp
4351 and then Nkind (Hi_Orig) = N_Attribute_Reference
4352 and then Attribute_Name (Hi_Orig) = Name_Last
4353 and then Nkind (Prefix (Hi_Orig)) in N_Has_Entity
4354 and then Entity (Prefix (Hi_Orig)) = Ltyp
4355 and then Comes_From_Source (N)
4356 and then VM_Target = No_VM
4358 Substitute_Valid_Check;
4362 -- If bounds of type are known at compile time, and the end points
4363 -- are known at compile time and identical, this is another case
4364 -- for substituting a valid test. We only do this for discrete
4365 -- types, since it won't arise in practice for float types.
4367 if Comes_From_Source (N)
4368 and then Is_Discrete_Type (Ltyp)
4369 and then Compile_Time_Known_Value (Type_High_Bound (Ltyp))
4370 and then Compile_Time_Known_Value (Type_Low_Bound (Ltyp))
4371 and then Compile_Time_Known_Value (Lo)
4372 and then Compile_Time_Known_Value (Hi)
4373 and then Expr_Value (Type_High_Bound (Ltyp)) = Expr_Value (Hi)
4374 and then Expr_Value (Type_Low_Bound (Ltyp)) = Expr_Value (Lo)
4376 -- Kill warnings in instances, since they may be cases where we
4377 -- have a test in the generic that makes sense with some types
4378 -- and not with other types.
4380 and then not In_Instance
4382 Substitute_Valid_Check;
4386 -- If we have an explicit range, do a bit of optimization based
4387 -- on range analysis (we may be able to kill one or both checks).
4389 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => False);
4390 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => False);
4392 -- If either check is known to fail, replace result by False since
4393 -- the other check does not matter. Preserve the static flag for
4394 -- legality checks, because we are constant-folding beyond RM 4.9.
4396 if Lcheck = LT or else Ucheck = GT then
4398 Error_Msg_N ("?range test optimized away", N);
4399 Error_Msg_N ("\?value is known to be out of range", N);
4403 New_Reference_To (Standard_False, Loc));
4404 Analyze_And_Resolve (N, Rtyp);
4405 Set_Is_Static_Expression (N, Static);
4409 -- If both checks are known to succeed, replace result by True,
4410 -- since we know we are in range.
4412 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
4414 Error_Msg_N ("?range test optimized away", N);
4415 Error_Msg_N ("\?value is known to be in range", N);
4419 New_Reference_To (Standard_True, Loc));
4420 Analyze_And_Resolve (N, Rtyp);
4421 Set_Is_Static_Expression (N, Static);
4425 -- If lower bound check succeeds and upper bound check is not
4426 -- known to succeed or fail, then replace the range check with
4427 -- a comparison against the upper bound.
4429 elsif Lcheck in Compare_GE then
4430 if Warn2 and then not In_Instance then
4431 Error_Msg_N ("?lower bound test optimized away", Lo);
4432 Error_Msg_N ("\?value is known to be in range", Lo);
4438 Right_Opnd => High_Bound (Rop)));
4439 Analyze_And_Resolve (N, Rtyp);
4443 -- If upper bound check succeeds and lower bound check is not
4444 -- known to succeed or fail, then replace the range check with
4445 -- a comparison against the lower bound.
4447 elsif Ucheck in Compare_LE then
4448 if Warn2 and then not In_Instance then
4449 Error_Msg_N ("?upper bound test optimized away", Hi);
4450 Error_Msg_N ("\?value is known to be in range", Hi);
4456 Right_Opnd => Low_Bound (Rop)));
4457 Analyze_And_Resolve (N, Rtyp);
4462 -- We couldn't optimize away the range check, but there is one
4463 -- more issue. If we are checking constant conditionals, then we
4464 -- see if we can determine the outcome assuming everything is
4465 -- valid, and if so give an appropriate warning.
4467 if Warn1 and then not Assume_No_Invalid_Values then
4468 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => True);
4469 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => True);
4471 -- Result is out of range for valid value
4473 if Lcheck = LT or else Ucheck = GT then
4475 ("?value can only be in range if it is invalid", N);
4477 -- Result is in range for valid value
4479 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
4481 ("?value can only be out of range if it is invalid", N);
4483 -- Lower bound check succeeds if value is valid
4485 elsif Warn2 and then Lcheck in Compare_GE then
4487 ("?lower bound check only fails if it is invalid", Lo);
4489 -- Upper bound check succeeds if value is valid
4491 elsif Warn2 and then Ucheck in Compare_LE then
4493 ("?upper bound check only fails for invalid values", Hi);
4498 -- For all other cases of an explicit range, nothing to be done
4502 -- Here right operand is a subtype mark
4506 Typ : Entity_Id := Etype (Rop);
4507 Is_Acc : constant Boolean := Is_Access_Type (Typ);
4508 Obj : Node_Id := Lop;
4509 Cond : Node_Id := Empty;
4512 Remove_Side_Effects (Obj);
4514 -- For tagged type, do tagged membership operation
4516 if Is_Tagged_Type (Typ) then
4518 -- No expansion will be performed when VM_Target, as the VM
4519 -- back-ends will handle the membership tests directly (tags
4520 -- are not explicitly represented in Java objects, so the
4521 -- normal tagged membership expansion is not what we want).
4523 if Tagged_Type_Expansion then
4524 Rewrite (N, Tagged_Membership (N));
4525 Analyze_And_Resolve (N, Rtyp);
4530 -- If type is scalar type, rewrite as x in t'first .. t'last.
4531 -- This reason we do this is that the bounds may have the wrong
4532 -- type if they come from the original type definition. Also this
4533 -- way we get all the processing above for an explicit range.
4535 elsif Is_Scalar_Type (Typ) then
4539 Make_Attribute_Reference (Loc,
4540 Attribute_Name => Name_First,
4541 Prefix => New_Reference_To (Typ, Loc)),
4544 Make_Attribute_Reference (Loc,
4545 Attribute_Name => Name_Last,
4546 Prefix => New_Reference_To (Typ, Loc))));
4547 Analyze_And_Resolve (N, Rtyp);
4550 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
4551 -- a membership test if the subtype mark denotes a constrained
4552 -- Unchecked_Union subtype and the expression lacks inferable
4555 elsif Is_Unchecked_Union (Base_Type (Typ))
4556 and then Is_Constrained (Typ)
4557 and then not Has_Inferable_Discriminants (Lop)
4560 Make_Raise_Program_Error (Loc,
4561 Reason => PE_Unchecked_Union_Restriction));
4563 -- Prevent Gigi from generating incorrect code by rewriting
4564 -- the test as a standard False.
4567 New_Occurrence_Of (Standard_False, Loc));
4572 -- Here we have a non-scalar type
4575 Typ := Designated_Type (Typ);
4578 if not Is_Constrained (Typ) then
4580 New_Reference_To (Standard_True, Loc));
4581 Analyze_And_Resolve (N, Rtyp);
4583 -- For the constrained array case, we have to check the subscripts
4584 -- for an exact match if the lengths are non-zero (the lengths
4585 -- must match in any case).
4587 elsif Is_Array_Type (Typ) then
4589 Check_Subscripts : declare
4590 function Construct_Attribute_Reference
4593 Dim : Nat) return Node_Id;
4594 -- Build attribute reference E'Nam(Dim)
4596 -----------------------------------
4597 -- Construct_Attribute_Reference --
4598 -----------------------------------
4600 function Construct_Attribute_Reference
4603 Dim : Nat) return Node_Id
4607 Make_Attribute_Reference (Loc,
4609 Attribute_Name => Nam,
4610 Expressions => New_List (
4611 Make_Integer_Literal (Loc, Dim)));
4612 end Construct_Attribute_Reference;
4614 -- Start of processing for Check_Subscripts
4617 for J in 1 .. Number_Dimensions (Typ) loop
4618 Evolve_And_Then (Cond,
4621 Construct_Attribute_Reference
4622 (Duplicate_Subexpr_No_Checks (Obj),
4625 Construct_Attribute_Reference
4626 (New_Occurrence_Of (Typ, Loc), Name_First, J)));
4628 Evolve_And_Then (Cond,
4631 Construct_Attribute_Reference
4632 (Duplicate_Subexpr_No_Checks (Obj),
4635 Construct_Attribute_Reference
4636 (New_Occurrence_Of (Typ, Loc), Name_Last, J)));
4645 Right_Opnd => Make_Null (Loc)),
4646 Right_Opnd => Cond);
4650 Analyze_And_Resolve (N, Rtyp);
4651 end Check_Subscripts;
4653 -- These are the cases where constraint checks may be required,
4654 -- e.g. records with possible discriminants
4657 -- Expand the test into a series of discriminant comparisons.
4658 -- The expression that is built is the negation of the one that
4659 -- is used for checking discriminant constraints.
4661 Obj := Relocate_Node (Left_Opnd (N));
4663 if Has_Discriminants (Typ) then
4664 Cond := Make_Op_Not (Loc,
4665 Right_Opnd => Build_Discriminant_Checks (Obj, Typ));
4668 Cond := Make_Or_Else (Loc,
4672 Right_Opnd => Make_Null (Loc)),
4673 Right_Opnd => Cond);
4677 Cond := New_Occurrence_Of (Standard_True, Loc);
4681 Analyze_And_Resolve (N, Rtyp);
4687 --------------------------------
4688 -- Expand_N_Indexed_Component --
4689 --------------------------------
4691 procedure Expand_N_Indexed_Component (N : Node_Id) is
4692 Loc : constant Source_Ptr := Sloc (N);
4693 Typ : constant Entity_Id := Etype (N);
4694 P : constant Node_Id := Prefix (N);
4695 T : constant Entity_Id := Etype (P);
4698 -- A special optimization, if we have an indexed component that is
4699 -- selecting from a slice, then we can eliminate the slice, since, for
4700 -- example, x (i .. j)(k) is identical to x(k). The only difference is
4701 -- the range check required by the slice. The range check for the slice
4702 -- itself has already been generated. The range check for the
4703 -- subscripting operation is ensured by converting the subject to
4704 -- the subtype of the slice.
4706 -- This optimization not only generates better code, avoiding slice
4707 -- messing especially in the packed case, but more importantly bypasses
4708 -- some problems in handling this peculiar case, for example, the issue
4709 -- of dealing specially with object renamings.
4711 if Nkind (P) = N_Slice then
4713 Make_Indexed_Component (Loc,
4714 Prefix => Prefix (P),
4715 Expressions => New_List (
4717 (Etype (First_Index (Etype (P))),
4718 First (Expressions (N))))));
4719 Analyze_And_Resolve (N, Typ);
4723 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
4724 -- function, then additional actuals must be passed.
4726 if Ada_Version >= Ada_05
4727 and then Is_Build_In_Place_Function_Call (P)
4729 Make_Build_In_Place_Call_In_Anonymous_Context (P);
4732 -- If the prefix is an access type, then we unconditionally rewrite if
4733 -- as an explicit dereference. This simplifies processing for several
4734 -- cases, including packed array cases and certain cases in which checks
4735 -- must be generated. We used to try to do this only when it was
4736 -- necessary, but it cleans up the code to do it all the time.
4738 if Is_Access_Type (T) then
4739 Insert_Explicit_Dereference (P);
4740 Analyze_And_Resolve (P, Designated_Type (T));
4743 -- Generate index and validity checks
4745 Generate_Index_Checks (N);
4747 if Validity_Checks_On and then Validity_Check_Subscripts then
4748 Apply_Subscript_Validity_Checks (N);
4751 -- All done for the non-packed case
4753 if not Is_Packed (Etype (Prefix (N))) then
4757 -- For packed arrays that are not bit-packed (i.e. the case of an array
4758 -- with one or more index types with a non-contiguous enumeration type),
4759 -- we can always use the normal packed element get circuit.
4761 if not Is_Bit_Packed_Array (Etype (Prefix (N))) then
4762 Expand_Packed_Element_Reference (N);
4766 -- For a reference to a component of a bit packed array, we have to
4767 -- convert it to a reference to the corresponding Packed_Array_Type.
4768 -- We only want to do this for simple references, and not for:
4770 -- Left side of assignment, or prefix of left side of assignment, or
4771 -- prefix of the prefix, to handle packed arrays of packed arrays,
4772 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
4774 -- Renaming objects in renaming associations
4775 -- This case is handled when a use of the renamed variable occurs
4777 -- Actual parameters for a procedure call
4778 -- This case is handled in Exp_Ch6.Expand_Actuals
4780 -- The second expression in a 'Read attribute reference
4782 -- The prefix of an address or size attribute reference
4784 -- The following circuit detects these exceptions
4787 Child : Node_Id := N;
4788 Parnt : Node_Id := Parent (N);
4792 if Nkind (Parnt) = N_Unchecked_Expression then
4795 elsif Nkind_In (Parnt, N_Object_Renaming_Declaration,
4796 N_Procedure_Call_Statement)
4797 or else (Nkind (Parnt) = N_Parameter_Association
4799 Nkind (Parent (Parnt)) = N_Procedure_Call_Statement)
4803 elsif Nkind (Parnt) = N_Attribute_Reference
4804 and then (Attribute_Name (Parnt) = Name_Address
4806 Attribute_Name (Parnt) = Name_Size)
4807 and then Prefix (Parnt) = Child
4811 elsif Nkind (Parnt) = N_Assignment_Statement
4812 and then Name (Parnt) = Child
4816 -- If the expression is an index of an indexed component, it must
4817 -- be expanded regardless of context.
4819 elsif Nkind (Parnt) = N_Indexed_Component
4820 and then Child /= Prefix (Parnt)
4822 Expand_Packed_Element_Reference (N);
4825 elsif Nkind (Parent (Parnt)) = N_Assignment_Statement
4826 and then Name (Parent (Parnt)) = Parnt
4830 elsif Nkind (Parnt) = N_Attribute_Reference
4831 and then Attribute_Name (Parnt) = Name_Read
4832 and then Next (First (Expressions (Parnt))) = Child
4836 elsif Nkind_In (Parnt, N_Indexed_Component, N_Selected_Component)
4837 and then Prefix (Parnt) = Child
4842 Expand_Packed_Element_Reference (N);
4846 -- Keep looking up tree for unchecked expression, or if we are the
4847 -- prefix of a possible assignment left side.
4850 Parnt := Parent (Child);
4853 end Expand_N_Indexed_Component;
4855 ---------------------
4856 -- Expand_N_Not_In --
4857 ---------------------
4859 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
4860 -- can be done. This avoids needing to duplicate this expansion code.
4862 procedure Expand_N_Not_In (N : Node_Id) is
4863 Loc : constant Source_Ptr := Sloc (N);
4864 Typ : constant Entity_Id := Etype (N);
4865 Cfs : constant Boolean := Comes_From_Source (N);
4872 Left_Opnd => Left_Opnd (N),
4873 Right_Opnd => Right_Opnd (N))));
4875 -- If this is a set membership, preserve list of alternatives
4877 Set_Alternatives (Right_Opnd (N), Alternatives (Original_Node (N)));
4879 -- We want this to appear as coming from source if original does (see
4880 -- transformations in Expand_N_In).
4882 Set_Comes_From_Source (N, Cfs);
4883 Set_Comes_From_Source (Right_Opnd (N), Cfs);
4885 -- Now analyze transformed node
4887 Analyze_And_Resolve (N, Typ);
4888 end Expand_N_Not_In;
4894 -- The only replacement required is for the case of a null of type that is
4895 -- an access to protected subprogram. We represent such access values as a
4896 -- record, and so we must replace the occurrence of null by the equivalent
4897 -- record (with a null address and a null pointer in it), so that the
4898 -- backend creates the proper value.
4900 procedure Expand_N_Null (N : Node_Id) is
4901 Loc : constant Source_Ptr := Sloc (N);
4902 Typ : constant Entity_Id := Etype (N);
4906 if Is_Access_Protected_Subprogram_Type (Typ) then
4908 Make_Aggregate (Loc,
4909 Expressions => New_List (
4910 New_Occurrence_Of (RTE (RE_Null_Address), Loc),
4914 Analyze_And_Resolve (N, Equivalent_Type (Typ));
4916 -- For subsequent semantic analysis, the node must retain its type.
4917 -- Gigi in any case replaces this type by the corresponding record
4918 -- type before processing the node.
4924 when RE_Not_Available =>
4928 ---------------------
4929 -- Expand_N_Op_Abs --
4930 ---------------------
4932 procedure Expand_N_Op_Abs (N : Node_Id) is
4933 Loc : constant Source_Ptr := Sloc (N);
4934 Expr : constant Node_Id := Right_Opnd (N);
4937 Unary_Op_Validity_Checks (N);
4939 -- Deal with software overflow checking
4941 if not Backend_Overflow_Checks_On_Target
4942 and then Is_Signed_Integer_Type (Etype (N))
4943 and then Do_Overflow_Check (N)
4945 -- The only case to worry about is when the argument is equal to the
4946 -- largest negative number, so what we do is to insert the check:
4948 -- [constraint_error when Expr = typ'Base'First]
4950 -- with the usual Duplicate_Subexpr use coding for expr
4953 Make_Raise_Constraint_Error (Loc,
4956 Left_Opnd => Duplicate_Subexpr (Expr),
4958 Make_Attribute_Reference (Loc,
4960 New_Occurrence_Of (Base_Type (Etype (Expr)), Loc),
4961 Attribute_Name => Name_First)),
4962 Reason => CE_Overflow_Check_Failed));
4965 -- Vax floating-point types case
4967 if Vax_Float (Etype (N)) then
4968 Expand_Vax_Arith (N);
4970 end Expand_N_Op_Abs;
4972 ---------------------
4973 -- Expand_N_Op_Add --
4974 ---------------------
4976 procedure Expand_N_Op_Add (N : Node_Id) is
4977 Typ : constant Entity_Id := Etype (N);
4980 Binary_Op_Validity_Checks (N);
4982 -- N + 0 = 0 + N = N for integer types
4984 if Is_Integer_Type (Typ) then
4985 if Compile_Time_Known_Value (Right_Opnd (N))
4986 and then Expr_Value (Right_Opnd (N)) = Uint_0
4988 Rewrite (N, Left_Opnd (N));
4991 elsif Compile_Time_Known_Value (Left_Opnd (N))
4992 and then Expr_Value (Left_Opnd (N)) = Uint_0
4994 Rewrite (N, Right_Opnd (N));
4999 -- Arithmetic overflow checks for signed integer/fixed point types
5001 if Is_Signed_Integer_Type (Typ)
5002 or else Is_Fixed_Point_Type (Typ)
5004 Apply_Arithmetic_Overflow_Check (N);
5007 -- Vax floating-point types case
5009 elsif Vax_Float (Typ) then
5010 Expand_Vax_Arith (N);
5012 end Expand_N_Op_Add;
5014 ---------------------
5015 -- Expand_N_Op_And --
5016 ---------------------
5018 procedure Expand_N_Op_And (N : Node_Id) is
5019 Typ : constant Entity_Id := Etype (N);
5022 Binary_Op_Validity_Checks (N);
5024 if Is_Array_Type (Etype (N)) then
5025 Expand_Boolean_Operator (N);
5027 elsif Is_Boolean_Type (Etype (N)) then
5028 Adjust_Condition (Left_Opnd (N));
5029 Adjust_Condition (Right_Opnd (N));
5030 Set_Etype (N, Standard_Boolean);
5031 Adjust_Result_Type (N, Typ);
5033 end Expand_N_Op_And;
5035 ------------------------
5036 -- Expand_N_Op_Concat --
5037 ------------------------
5039 procedure Expand_N_Op_Concat (N : Node_Id) is
5041 -- List of operands to be concatenated
5044 -- Node which is to be replaced by the result of concatenating the nodes
5045 -- in the list Opnds.
5048 -- Ensure validity of both operands
5050 Binary_Op_Validity_Checks (N);
5052 -- If we are the left operand of a concatenation higher up the tree,
5053 -- then do nothing for now, since we want to deal with a series of
5054 -- concatenations as a unit.
5056 if Nkind (Parent (N)) = N_Op_Concat
5057 and then N = Left_Opnd (Parent (N))
5062 -- We get here with a concatenation whose left operand may be a
5063 -- concatenation itself with a consistent type. We need to process
5064 -- these concatenation operands from left to right, which means
5065 -- from the deepest node in the tree to the highest node.
5068 while Nkind (Left_Opnd (Cnode)) = N_Op_Concat loop
5069 Cnode := Left_Opnd (Cnode);
5072 -- Now Opnd is the deepest Opnd, and its parents are the concatenation
5073 -- nodes above, so now we process bottom up, doing the operations. We
5074 -- gather a string that is as long as possible up to five operands
5076 -- The outer loop runs more than once if more than one concatenation
5077 -- type is involved.
5080 Opnds := New_List (Left_Opnd (Cnode), Right_Opnd (Cnode));
5081 Set_Parent (Opnds, N);
5083 -- The inner loop gathers concatenation operands
5085 Inner : while Cnode /= N
5086 and then Base_Type (Etype (Cnode)) =
5087 Base_Type (Etype (Parent (Cnode)))
5089 Cnode := Parent (Cnode);
5090 Append (Right_Opnd (Cnode), Opnds);
5093 Expand_Concatenate (Cnode, Opnds);
5095 exit Outer when Cnode = N;
5096 Cnode := Parent (Cnode);
5098 end Expand_N_Op_Concat;
5100 ------------------------
5101 -- Expand_N_Op_Divide --
5102 ------------------------
5104 procedure Expand_N_Op_Divide (N : Node_Id) is
5105 Loc : constant Source_Ptr := Sloc (N);
5106 Lopnd : constant Node_Id := Left_Opnd (N);
5107 Ropnd : constant Node_Id := Right_Opnd (N);
5108 Ltyp : constant Entity_Id := Etype (Lopnd);
5109 Rtyp : constant Entity_Id := Etype (Ropnd);
5110 Typ : Entity_Id := Etype (N);
5111 Rknow : constant Boolean := Is_Integer_Type (Typ)
5113 Compile_Time_Known_Value (Ropnd);
5117 Binary_Op_Validity_Checks (N);
5120 Rval := Expr_Value (Ropnd);
5123 -- N / 1 = N for integer types
5125 if Rknow and then Rval = Uint_1 then
5130 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
5131 -- Is_Power_Of_2_For_Shift is set means that we know that our left
5132 -- operand is an unsigned integer, as required for this to work.
5134 if Nkind (Ropnd) = N_Op_Expon
5135 and then Is_Power_Of_2_For_Shift (Ropnd)
5137 -- We cannot do this transformation in configurable run time mode if we
5138 -- have 64-bit -- integers and long shifts are not available.
5142 or else Support_Long_Shifts_On_Target)
5145 Make_Op_Shift_Right (Loc,
5148 Convert_To (Standard_Natural, Right_Opnd (Ropnd))));
5149 Analyze_And_Resolve (N, Typ);
5153 -- Do required fixup of universal fixed operation
5155 if Typ = Universal_Fixed then
5156 Fixup_Universal_Fixed_Operation (N);
5160 -- Divisions with fixed-point results
5162 if Is_Fixed_Point_Type (Typ) then
5164 -- No special processing if Treat_Fixed_As_Integer is set, since
5165 -- from a semantic point of view such operations are simply integer
5166 -- operations and will be treated that way.
5168 if not Treat_Fixed_As_Integer (N) then
5169 if Is_Integer_Type (Rtyp) then
5170 Expand_Divide_Fixed_By_Integer_Giving_Fixed (N);
5172 Expand_Divide_Fixed_By_Fixed_Giving_Fixed (N);
5176 -- Other cases of division of fixed-point operands. Again we exclude the
5177 -- case where Treat_Fixed_As_Integer is set.
5179 elsif (Is_Fixed_Point_Type (Ltyp) or else
5180 Is_Fixed_Point_Type (Rtyp))
5181 and then not Treat_Fixed_As_Integer (N)
5183 if Is_Integer_Type (Typ) then
5184 Expand_Divide_Fixed_By_Fixed_Giving_Integer (N);
5186 pragma Assert (Is_Floating_Point_Type (Typ));
5187 Expand_Divide_Fixed_By_Fixed_Giving_Float (N);
5190 -- Mixed-mode operations can appear in a non-static universal context,
5191 -- in which case the integer argument must be converted explicitly.
5193 elsif Typ = Universal_Real
5194 and then Is_Integer_Type (Rtyp)
5197 Convert_To (Universal_Real, Relocate_Node (Ropnd)));
5199 Analyze_And_Resolve (Ropnd, Universal_Real);
5201 elsif Typ = Universal_Real
5202 and then Is_Integer_Type (Ltyp)
5205 Convert_To (Universal_Real, Relocate_Node (Lopnd)));
5207 Analyze_And_Resolve (Lopnd, Universal_Real);
5209 -- Non-fixed point cases, do integer zero divide and overflow checks
5211 elsif Is_Integer_Type (Typ) then
5212 Apply_Divide_Check (N);
5214 -- Check for 64-bit division available, or long shifts if the divisor
5215 -- is a small power of 2 (since such divides will be converted into
5218 if Esize (Ltyp) > 32
5219 and then not Support_64_Bit_Divides_On_Target
5222 or else not Support_Long_Shifts_On_Target
5223 or else (Rval /= Uint_2 and then
5224 Rval /= Uint_4 and then
5225 Rval /= Uint_8 and then
5226 Rval /= Uint_16 and then
5227 Rval /= Uint_32 and then
5230 Error_Msg_CRT ("64-bit division", N);
5233 -- Deal with Vax_Float
5235 elsif Vax_Float (Typ) then
5236 Expand_Vax_Arith (N);
5239 end Expand_N_Op_Divide;
5241 --------------------
5242 -- Expand_N_Op_Eq --
5243 --------------------
5245 procedure Expand_N_Op_Eq (N : Node_Id) is
5246 Loc : constant Source_Ptr := Sloc (N);
5247 Typ : constant Entity_Id := Etype (N);
5248 Lhs : constant Node_Id := Left_Opnd (N);
5249 Rhs : constant Node_Id := Right_Opnd (N);
5250 Bodies : constant List_Id := New_List;
5251 A_Typ : constant Entity_Id := Etype (Lhs);
5253 Typl : Entity_Id := A_Typ;
5254 Op_Name : Entity_Id;
5257 procedure Build_Equality_Call (Eq : Entity_Id);
5258 -- If a constructed equality exists for the type or for its parent,
5259 -- build and analyze call, adding conversions if the operation is
5262 function Has_Unconstrained_UU_Component (Typ : Node_Id) return Boolean;
5263 -- Determines whether a type has a subcomponent of an unconstrained
5264 -- Unchecked_Union subtype. Typ is a record type.
5266 -------------------------
5267 -- Build_Equality_Call --
5268 -------------------------
5270 procedure Build_Equality_Call (Eq : Entity_Id) is
5271 Op_Type : constant Entity_Id := Etype (First_Formal (Eq));
5272 L_Exp : Node_Id := Relocate_Node (Lhs);
5273 R_Exp : Node_Id := Relocate_Node (Rhs);
5276 if Base_Type (Op_Type) /= Base_Type (A_Typ)
5277 and then not Is_Class_Wide_Type (A_Typ)
5279 L_Exp := OK_Convert_To (Op_Type, L_Exp);
5280 R_Exp := OK_Convert_To (Op_Type, R_Exp);
5283 -- If we have an Unchecked_Union, we need to add the inferred
5284 -- discriminant values as actuals in the function call. At this
5285 -- point, the expansion has determined that both operands have
5286 -- inferable discriminants.
5288 if Is_Unchecked_Union (Op_Type) then
5290 Lhs_Type : constant Node_Id := Etype (L_Exp);
5291 Rhs_Type : constant Node_Id := Etype (R_Exp);
5292 Lhs_Discr_Val : Node_Id;
5293 Rhs_Discr_Val : Node_Id;
5296 -- Per-object constrained selected components require special
5297 -- attention. If the enclosing scope of the component is an
5298 -- Unchecked_Union, we cannot reference its discriminants
5299 -- directly. This is why we use the two extra parameters of
5300 -- the equality function of the enclosing Unchecked_Union.
5302 -- type UU_Type (Discr : Integer := 0) is
5305 -- pragma Unchecked_Union (UU_Type);
5307 -- 1. Unchecked_Union enclosing record:
5309 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
5311 -- Comp : UU_Type (Discr);
5313 -- end Enclosing_UU_Type;
5314 -- pragma Unchecked_Union (Enclosing_UU_Type);
5316 -- Obj1 : Enclosing_UU_Type;
5317 -- Obj2 : Enclosing_UU_Type (1);
5319 -- [. . .] Obj1 = Obj2 [. . .]
5323 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
5325 -- A and B are the formal parameters of the equality function
5326 -- of Enclosing_UU_Type. The function always has two extra
5327 -- formals to capture the inferred discriminant values.
5329 -- 2. Non-Unchecked_Union enclosing record:
5332 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
5335 -- Comp : UU_Type (Discr);
5337 -- end Enclosing_Non_UU_Type;
5339 -- Obj1 : Enclosing_Non_UU_Type;
5340 -- Obj2 : Enclosing_Non_UU_Type (1);
5342 -- ... Obj1 = Obj2 ...
5346 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
5347 -- obj1.discr, obj2.discr)) then
5349 -- In this case we can directly reference the discriminants of
5350 -- the enclosing record.
5354 if Nkind (Lhs) = N_Selected_Component
5355 and then Has_Per_Object_Constraint
5356 (Entity (Selector_Name (Lhs)))
5358 -- Enclosing record is an Unchecked_Union, use formal A
5360 if Is_Unchecked_Union (Scope
5361 (Entity (Selector_Name (Lhs))))
5364 Make_Identifier (Loc,
5367 -- Enclosing record is of a non-Unchecked_Union type, it is
5368 -- possible to reference the discriminant.
5372 Make_Selected_Component (Loc,
5373 Prefix => Prefix (Lhs),
5376 (Get_Discriminant_Value
5377 (First_Discriminant (Lhs_Type),
5379 Stored_Constraint (Lhs_Type))));
5382 -- Comment needed here ???
5385 -- Infer the discriminant value
5389 (Get_Discriminant_Value
5390 (First_Discriminant (Lhs_Type),
5392 Stored_Constraint (Lhs_Type)));
5397 if Nkind (Rhs) = N_Selected_Component
5398 and then Has_Per_Object_Constraint
5399 (Entity (Selector_Name (Rhs)))
5401 if Is_Unchecked_Union
5402 (Scope (Entity (Selector_Name (Rhs))))
5405 Make_Identifier (Loc,
5410 Make_Selected_Component (Loc,
5411 Prefix => Prefix (Rhs),
5413 New_Copy (Get_Discriminant_Value (
5414 First_Discriminant (Rhs_Type),
5416 Stored_Constraint (Rhs_Type))));
5421 New_Copy (Get_Discriminant_Value (
5422 First_Discriminant (Rhs_Type),
5424 Stored_Constraint (Rhs_Type)));
5429 Make_Function_Call (Loc,
5430 Name => New_Reference_To (Eq, Loc),
5431 Parameter_Associations => New_List (
5438 -- Normal case, not an unchecked union
5442 Make_Function_Call (Loc,
5443 Name => New_Reference_To (Eq, Loc),
5444 Parameter_Associations => New_List (L_Exp, R_Exp)));
5447 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5448 end Build_Equality_Call;
5450 ------------------------------------
5451 -- Has_Unconstrained_UU_Component --
5452 ------------------------------------
5454 function Has_Unconstrained_UU_Component
5455 (Typ : Node_Id) return Boolean
5457 Tdef : constant Node_Id :=
5458 Type_Definition (Declaration_Node (Base_Type (Typ)));
5462 function Component_Is_Unconstrained_UU
5463 (Comp : Node_Id) return Boolean;
5464 -- Determines whether the subtype of the component is an
5465 -- unconstrained Unchecked_Union.
5467 function Variant_Is_Unconstrained_UU
5468 (Variant : Node_Id) return Boolean;
5469 -- Determines whether a component of the variant has an unconstrained
5470 -- Unchecked_Union subtype.
5472 -----------------------------------
5473 -- Component_Is_Unconstrained_UU --
5474 -----------------------------------
5476 function Component_Is_Unconstrained_UU
5477 (Comp : Node_Id) return Boolean
5480 if Nkind (Comp) /= N_Component_Declaration then
5485 Sindic : constant Node_Id :=
5486 Subtype_Indication (Component_Definition (Comp));
5489 -- Unconstrained nominal type. In the case of a constraint
5490 -- present, the node kind would have been N_Subtype_Indication.
5492 if Nkind (Sindic) = N_Identifier then
5493 return Is_Unchecked_Union (Base_Type (Etype (Sindic)));
5498 end Component_Is_Unconstrained_UU;
5500 ---------------------------------
5501 -- Variant_Is_Unconstrained_UU --
5502 ---------------------------------
5504 function Variant_Is_Unconstrained_UU
5505 (Variant : Node_Id) return Boolean
5507 Clist : constant Node_Id := Component_List (Variant);
5510 if Is_Empty_List (Component_Items (Clist)) then
5514 -- We only need to test one component
5517 Comp : Node_Id := First (Component_Items (Clist));
5520 while Present (Comp) loop
5521 if Component_Is_Unconstrained_UU (Comp) then
5529 -- None of the components withing the variant were of
5530 -- unconstrained Unchecked_Union type.
5533 end Variant_Is_Unconstrained_UU;
5535 -- Start of processing for Has_Unconstrained_UU_Component
5538 if Null_Present (Tdef) then
5542 Clist := Component_List (Tdef);
5543 Vpart := Variant_Part (Clist);
5545 -- Inspect available components
5547 if Present (Component_Items (Clist)) then
5549 Comp : Node_Id := First (Component_Items (Clist));
5552 while Present (Comp) loop
5554 -- One component is sufficient
5556 if Component_Is_Unconstrained_UU (Comp) then
5565 -- Inspect available components withing variants
5567 if Present (Vpart) then
5569 Variant : Node_Id := First (Variants (Vpart));
5572 while Present (Variant) loop
5574 -- One component within a variant is sufficient
5576 if Variant_Is_Unconstrained_UU (Variant) then
5585 -- Neither the available components, nor the components inside the
5586 -- variant parts were of an unconstrained Unchecked_Union subtype.
5589 end Has_Unconstrained_UU_Component;
5591 -- Start of processing for Expand_N_Op_Eq
5594 Binary_Op_Validity_Checks (N);
5596 if Ekind (Typl) = E_Private_Type then
5597 Typl := Underlying_Type (Typl);
5598 elsif Ekind (Typl) = E_Private_Subtype then
5599 Typl := Underlying_Type (Base_Type (Typl));
5604 -- It may happen in error situations that the underlying type is not
5605 -- set. The error will be detected later, here we just defend the
5612 Typl := Base_Type (Typl);
5614 -- Boolean types (requiring handling of non-standard case)
5616 if Is_Boolean_Type (Typl) then
5617 Adjust_Condition (Left_Opnd (N));
5618 Adjust_Condition (Right_Opnd (N));
5619 Set_Etype (N, Standard_Boolean);
5620 Adjust_Result_Type (N, Typ);
5624 elsif Is_Array_Type (Typl) then
5626 -- If we are doing full validity checking, and it is possible for the
5627 -- array elements to be invalid then expand out array comparisons to
5628 -- make sure that we check the array elements.
5630 if Validity_Check_Operands
5631 and then not Is_Known_Valid (Component_Type (Typl))
5634 Save_Force_Validity_Checks : constant Boolean :=
5635 Force_Validity_Checks;
5637 Force_Validity_Checks := True;
5639 Expand_Array_Equality
5641 Relocate_Node (Lhs),
5642 Relocate_Node (Rhs),
5645 Insert_Actions (N, Bodies);
5646 Analyze_And_Resolve (N, Standard_Boolean);
5647 Force_Validity_Checks := Save_Force_Validity_Checks;
5650 -- Packed case where both operands are known aligned
5652 elsif Is_Bit_Packed_Array (Typl)
5653 and then not Is_Possibly_Unaligned_Object (Lhs)
5654 and then not Is_Possibly_Unaligned_Object (Rhs)
5656 Expand_Packed_Eq (N);
5658 -- Where the component type is elementary we can use a block bit
5659 -- comparison (if supported on the target) exception in the case
5660 -- of floating-point (negative zero issues require element by
5661 -- element comparison), and atomic types (where we must be sure
5662 -- to load elements independently) and possibly unaligned arrays.
5664 elsif Is_Elementary_Type (Component_Type (Typl))
5665 and then not Is_Floating_Point_Type (Component_Type (Typl))
5666 and then not Is_Atomic (Component_Type (Typl))
5667 and then not Is_Possibly_Unaligned_Object (Lhs)
5668 and then not Is_Possibly_Unaligned_Object (Rhs)
5669 and then Support_Composite_Compare_On_Target
5673 -- For composite and floating-point cases, expand equality loop to
5674 -- make sure of using proper comparisons for tagged types, and
5675 -- correctly handling the floating-point case.
5679 Expand_Array_Equality
5681 Relocate_Node (Lhs),
5682 Relocate_Node (Rhs),
5685 Insert_Actions (N, Bodies, Suppress => All_Checks);
5686 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5691 elsif Is_Record_Type (Typl) then
5693 -- For tagged types, use the primitive "="
5695 if Is_Tagged_Type (Typl) then
5697 -- No need to do anything else compiling under restriction
5698 -- No_Dispatching_Calls. During the semantic analysis we
5699 -- already notified such violation.
5701 if Restriction_Active (No_Dispatching_Calls) then
5705 -- If this is derived from an untagged private type completed with
5706 -- a tagged type, it does not have a full view, so we use the
5707 -- primitive operations of the private type. This check should no
5708 -- longer be necessary when these types get their full views???
5710 if Is_Private_Type (A_Typ)
5711 and then not Is_Tagged_Type (A_Typ)
5712 and then Is_Derived_Type (A_Typ)
5713 and then No (Full_View (A_Typ))
5715 -- Search for equality operation, checking that the operands
5716 -- have the same type. Note that we must find a matching entry,
5717 -- or something is very wrong!
5719 Prim := First_Elmt (Collect_Primitive_Operations (A_Typ));
5721 while Present (Prim) loop
5722 exit when Chars (Node (Prim)) = Name_Op_Eq
5723 and then Etype (First_Formal (Node (Prim))) =
5724 Etype (Next_Formal (First_Formal (Node (Prim))))
5726 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
5731 pragma Assert (Present (Prim));
5732 Op_Name := Node (Prim);
5734 -- Find the type's predefined equality or an overriding
5735 -- user- defined equality. The reason for not simply calling
5736 -- Find_Prim_Op here is that there may be a user-defined
5737 -- overloaded equality op that precedes the equality that we want,
5738 -- so we have to explicitly search (e.g., there could be an
5739 -- equality with two different parameter types).
5742 if Is_Class_Wide_Type (Typl) then
5743 Typl := Root_Type (Typl);
5746 Prim := First_Elmt (Primitive_Operations (Typl));
5747 while Present (Prim) loop
5748 exit when Chars (Node (Prim)) = Name_Op_Eq
5749 and then Etype (First_Formal (Node (Prim))) =
5750 Etype (Next_Formal (First_Formal (Node (Prim))))
5752 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
5757 pragma Assert (Present (Prim));
5758 Op_Name := Node (Prim);
5761 Build_Equality_Call (Op_Name);
5763 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
5764 -- predefined equality operator for a type which has a subcomponent
5765 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
5767 elsif Has_Unconstrained_UU_Component (Typl) then
5769 Make_Raise_Program_Error (Loc,
5770 Reason => PE_Unchecked_Union_Restriction));
5772 -- Prevent Gigi from generating incorrect code by rewriting the
5773 -- equality as a standard False.
5776 New_Occurrence_Of (Standard_False, Loc));
5778 elsif Is_Unchecked_Union (Typl) then
5780 -- If we can infer the discriminants of the operands, we make a
5781 -- call to the TSS equality function.
5783 if Has_Inferable_Discriminants (Lhs)
5785 Has_Inferable_Discriminants (Rhs)
5788 (TSS (Root_Type (Typl), TSS_Composite_Equality));
5791 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
5792 -- the predefined equality operator for an Unchecked_Union type
5793 -- if either of the operands lack inferable discriminants.
5796 Make_Raise_Program_Error (Loc,
5797 Reason => PE_Unchecked_Union_Restriction));
5799 -- Prevent Gigi from generating incorrect code by rewriting
5800 -- the equality as a standard False.
5803 New_Occurrence_Of (Standard_False, Loc));
5807 -- If a type support function is present (for complex cases), use it
5809 elsif Present (TSS (Root_Type (Typl), TSS_Composite_Equality)) then
5811 (TSS (Root_Type (Typl), TSS_Composite_Equality));
5813 -- Otherwise expand the component by component equality. Note that
5814 -- we never use block-bit comparisons for records, because of the
5815 -- problems with gaps. The backend will often be able to recombine
5816 -- the separate comparisons that we generate here.
5819 Remove_Side_Effects (Lhs);
5820 Remove_Side_Effects (Rhs);
5822 Expand_Record_Equality (N, Typl, Lhs, Rhs, Bodies));
5824 Insert_Actions (N, Bodies, Suppress => All_Checks);
5825 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5829 -- Test if result is known at compile time
5831 Rewrite_Comparison (N);
5833 -- If we still have comparison for Vax_Float, process it
5835 if Vax_Float (Typl) and then Nkind (N) in N_Op_Compare then
5836 Expand_Vax_Comparison (N);
5841 -----------------------
5842 -- Expand_N_Op_Expon --
5843 -----------------------
5845 procedure Expand_N_Op_Expon (N : Node_Id) is
5846 Loc : constant Source_Ptr := Sloc (N);
5847 Typ : constant Entity_Id := Etype (N);
5848 Rtyp : constant Entity_Id := Root_Type (Typ);
5849 Base : constant Node_Id := Relocate_Node (Left_Opnd (N));
5850 Bastyp : constant Node_Id := Etype (Base);
5851 Exp : constant Node_Id := Relocate_Node (Right_Opnd (N));
5852 Exptyp : constant Entity_Id := Etype (Exp);
5853 Ovflo : constant Boolean := Do_Overflow_Check (N);
5862 Binary_Op_Validity_Checks (N);
5864 -- If either operand is of a private type, then we have the use of an
5865 -- intrinsic operator, and we get rid of the privateness, by using root
5866 -- types of underlying types for the actual operation. Otherwise the
5867 -- private types will cause trouble if we expand multiplications or
5868 -- shifts etc. We also do this transformation if the result type is
5869 -- different from the base type.
5871 if Is_Private_Type (Etype (Base))
5873 Is_Private_Type (Typ)
5875 Is_Private_Type (Exptyp)
5877 Rtyp /= Root_Type (Bastyp)
5880 Bt : constant Entity_Id := Root_Type (Underlying_Type (Bastyp));
5881 Et : constant Entity_Id := Root_Type (Underlying_Type (Exptyp));
5885 Unchecked_Convert_To (Typ,
5887 Left_Opnd => Unchecked_Convert_To (Bt, Base),
5888 Right_Opnd => Unchecked_Convert_To (Et, Exp))));
5889 Analyze_And_Resolve (N, Typ);
5894 -- Test for case of known right argument
5896 if Compile_Time_Known_Value (Exp) then
5897 Expv := Expr_Value (Exp);
5899 -- We only fold small non-negative exponents. You might think we
5900 -- could fold small negative exponents for the real case, but we
5901 -- can't because we are required to raise Constraint_Error for
5902 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
5903 -- See ACVC test C4A012B.
5905 if Expv >= 0 and then Expv <= 4 then
5907 -- X ** 0 = 1 (or 1.0)
5911 -- Call Remove_Side_Effects to ensure that any side effects
5912 -- in the ignored left operand (in particular function calls
5913 -- to user defined functions) are properly executed.
5915 Remove_Side_Effects (Base);
5917 if Ekind (Typ) in Integer_Kind then
5918 Xnode := Make_Integer_Literal (Loc, Intval => 1);
5920 Xnode := Make_Real_Literal (Loc, Ureal_1);
5932 Make_Op_Multiply (Loc,
5933 Left_Opnd => Duplicate_Subexpr (Base),
5934 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
5936 -- X ** 3 = X * X * X
5940 Make_Op_Multiply (Loc,
5942 Make_Op_Multiply (Loc,
5943 Left_Opnd => Duplicate_Subexpr (Base),
5944 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)),
5945 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
5948 -- En : constant base'type := base * base;
5954 Make_Defining_Identifier (Loc, New_Internal_Name ('E'));
5956 Insert_Actions (N, New_List (
5957 Make_Object_Declaration (Loc,
5958 Defining_Identifier => Temp,
5959 Constant_Present => True,
5960 Object_Definition => New_Reference_To (Typ, Loc),
5962 Make_Op_Multiply (Loc,
5963 Left_Opnd => Duplicate_Subexpr (Base),
5964 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)))));
5967 Make_Op_Multiply (Loc,
5968 Left_Opnd => New_Reference_To (Temp, Loc),
5969 Right_Opnd => New_Reference_To (Temp, Loc));
5973 Analyze_And_Resolve (N, Typ);
5978 -- Case of (2 ** expression) appearing as an argument of an integer
5979 -- multiplication, or as the right argument of a division of a non-
5980 -- negative integer. In such cases we leave the node untouched, setting
5981 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
5982 -- of the higher level node converts it into a shift.
5984 -- Note: this transformation is not applicable for a modular type with
5985 -- a non-binary modulus in the multiplication case, since we get a wrong
5986 -- result if the shift causes an overflow before the modular reduction.
5988 if Nkind (Base) = N_Integer_Literal
5989 and then Intval (Base) = 2
5990 and then Is_Integer_Type (Root_Type (Exptyp))
5991 and then Esize (Root_Type (Exptyp)) <= Esize (Standard_Integer)
5992 and then Is_Unsigned_Type (Exptyp)
5994 and then Nkind (Parent (N)) in N_Binary_Op
5997 P : constant Node_Id := Parent (N);
5998 L : constant Node_Id := Left_Opnd (P);
5999 R : constant Node_Id := Right_Opnd (P);
6002 if (Nkind (P) = N_Op_Multiply
6003 and then not Non_Binary_Modulus (Typ)
6005 ((Is_Integer_Type (Etype (L)) and then R = N)
6007 (Is_Integer_Type (Etype (R)) and then L = N))
6008 and then not Do_Overflow_Check (P))
6011 (Nkind (P) = N_Op_Divide
6012 and then Is_Integer_Type (Etype (L))
6013 and then Is_Unsigned_Type (Etype (L))
6015 and then not Do_Overflow_Check (P))
6017 Set_Is_Power_Of_2_For_Shift (N);
6023 -- Fall through if exponentiation must be done using a runtime routine
6025 -- First deal with modular case
6027 if Is_Modular_Integer_Type (Rtyp) then
6029 -- Non-binary case, we call the special exponentiation routine for
6030 -- the non-binary case, converting the argument to Long_Long_Integer
6031 -- and passing the modulus value. Then the result is converted back
6032 -- to the base type.
6034 if Non_Binary_Modulus (Rtyp) then
6037 Make_Function_Call (Loc,
6038 Name => New_Reference_To (RTE (RE_Exp_Modular), Loc),
6039 Parameter_Associations => New_List (
6040 Convert_To (Standard_Integer, Base),
6041 Make_Integer_Literal (Loc, Modulus (Rtyp)),
6044 -- Binary case, in this case, we call one of two routines, either the
6045 -- unsigned integer case, or the unsigned long long integer case,
6046 -- with a final "and" operation to do the required mod.
6049 if UI_To_Int (Esize (Rtyp)) <= Standard_Integer_Size then
6050 Ent := RTE (RE_Exp_Unsigned);
6052 Ent := RTE (RE_Exp_Long_Long_Unsigned);
6059 Make_Function_Call (Loc,
6060 Name => New_Reference_To (Ent, Loc),
6061 Parameter_Associations => New_List (
6062 Convert_To (Etype (First_Formal (Ent)), Base),
6065 Make_Integer_Literal (Loc, Modulus (Rtyp) - 1))));
6069 -- Common exit point for modular type case
6071 Analyze_And_Resolve (N, Typ);
6074 -- Signed integer cases, done using either Integer or Long_Long_Integer.
6075 -- It is not worth having routines for Short_[Short_]Integer, since for
6076 -- most machines it would not help, and it would generate more code that
6077 -- might need certification when a certified run time is required.
6079 -- In the integer cases, we have two routines, one for when overflow
6080 -- checks are required, and one when they are not required, since there
6081 -- is a real gain in omitting checks on many machines.
6083 elsif Rtyp = Base_Type (Standard_Long_Long_Integer)
6084 or else (Rtyp = Base_Type (Standard_Long_Integer)
6086 Esize (Standard_Long_Integer) > Esize (Standard_Integer))
6087 or else (Rtyp = Universal_Integer)
6089 Etyp := Standard_Long_Long_Integer;
6092 Rent := RE_Exp_Long_Long_Integer;
6094 Rent := RE_Exn_Long_Long_Integer;
6097 elsif Is_Signed_Integer_Type (Rtyp) then
6098 Etyp := Standard_Integer;
6101 Rent := RE_Exp_Integer;
6103 Rent := RE_Exn_Integer;
6106 -- Floating-point cases, always done using Long_Long_Float. We do not
6107 -- need separate routines for the overflow case here, since in the case
6108 -- of floating-point, we generate infinities anyway as a rule (either
6109 -- that or we automatically trap overflow), and if there is an infinity
6110 -- generated and a range check is required, the check will fail anyway.
6113 pragma Assert (Is_Floating_Point_Type (Rtyp));
6114 Etyp := Standard_Long_Long_Float;
6115 Rent := RE_Exn_Long_Long_Float;
6118 -- Common processing for integer cases and floating-point cases.
6119 -- If we are in the right type, we can call runtime routine directly
6122 and then Rtyp /= Universal_Integer
6123 and then Rtyp /= Universal_Real
6126 Make_Function_Call (Loc,
6127 Name => New_Reference_To (RTE (Rent), Loc),
6128 Parameter_Associations => New_List (Base, Exp)));
6130 -- Otherwise we have to introduce conversions (conversions are also
6131 -- required in the universal cases, since the runtime routine is
6132 -- typed using one of the standard types).
6137 Make_Function_Call (Loc,
6138 Name => New_Reference_To (RTE (Rent), Loc),
6139 Parameter_Associations => New_List (
6140 Convert_To (Etyp, Base),
6144 Analyze_And_Resolve (N, Typ);
6148 when RE_Not_Available =>
6150 end Expand_N_Op_Expon;
6152 --------------------
6153 -- Expand_N_Op_Ge --
6154 --------------------
6156 procedure Expand_N_Op_Ge (N : Node_Id) is
6157 Typ : constant Entity_Id := Etype (N);
6158 Op1 : constant Node_Id := Left_Opnd (N);
6159 Op2 : constant Node_Id := Right_Opnd (N);
6160 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6163 Binary_Op_Validity_Checks (N);
6165 if Is_Array_Type (Typ1) then
6166 Expand_Array_Comparison (N);
6170 if Is_Boolean_Type (Typ1) then
6171 Adjust_Condition (Op1);
6172 Adjust_Condition (Op2);
6173 Set_Etype (N, Standard_Boolean);
6174 Adjust_Result_Type (N, Typ);
6177 Rewrite_Comparison (N);
6179 -- If we still have comparison, and Vax_Float type, process it
6181 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6182 Expand_Vax_Comparison (N);
6187 --------------------
6188 -- Expand_N_Op_Gt --
6189 --------------------
6191 procedure Expand_N_Op_Gt (N : Node_Id) is
6192 Typ : constant Entity_Id := Etype (N);
6193 Op1 : constant Node_Id := Left_Opnd (N);
6194 Op2 : constant Node_Id := Right_Opnd (N);
6195 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6198 Binary_Op_Validity_Checks (N);
6200 if Is_Array_Type (Typ1) then
6201 Expand_Array_Comparison (N);
6205 if Is_Boolean_Type (Typ1) then
6206 Adjust_Condition (Op1);
6207 Adjust_Condition (Op2);
6208 Set_Etype (N, Standard_Boolean);
6209 Adjust_Result_Type (N, Typ);
6212 Rewrite_Comparison (N);
6214 -- If we still have comparison, and Vax_Float type, process it
6216 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6217 Expand_Vax_Comparison (N);
6222 --------------------
6223 -- Expand_N_Op_Le --
6224 --------------------
6226 procedure Expand_N_Op_Le (N : Node_Id) is
6227 Typ : constant Entity_Id := Etype (N);
6228 Op1 : constant Node_Id := Left_Opnd (N);
6229 Op2 : constant Node_Id := Right_Opnd (N);
6230 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6233 Binary_Op_Validity_Checks (N);
6235 if Is_Array_Type (Typ1) then
6236 Expand_Array_Comparison (N);
6240 if Is_Boolean_Type (Typ1) then
6241 Adjust_Condition (Op1);
6242 Adjust_Condition (Op2);
6243 Set_Etype (N, Standard_Boolean);
6244 Adjust_Result_Type (N, Typ);
6247 Rewrite_Comparison (N);
6249 -- If we still have comparison, and Vax_Float type, process it
6251 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6252 Expand_Vax_Comparison (N);
6257 --------------------
6258 -- Expand_N_Op_Lt --
6259 --------------------
6261 procedure Expand_N_Op_Lt (N : Node_Id) is
6262 Typ : constant Entity_Id := Etype (N);
6263 Op1 : constant Node_Id := Left_Opnd (N);
6264 Op2 : constant Node_Id := Right_Opnd (N);
6265 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6268 Binary_Op_Validity_Checks (N);
6270 if Is_Array_Type (Typ1) then
6271 Expand_Array_Comparison (N);
6275 if Is_Boolean_Type (Typ1) then
6276 Adjust_Condition (Op1);
6277 Adjust_Condition (Op2);
6278 Set_Etype (N, Standard_Boolean);
6279 Adjust_Result_Type (N, Typ);
6282 Rewrite_Comparison (N);
6284 -- If we still have comparison, and Vax_Float type, process it
6286 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6287 Expand_Vax_Comparison (N);
6292 -----------------------
6293 -- Expand_N_Op_Minus --
6294 -----------------------
6296 procedure Expand_N_Op_Minus (N : Node_Id) is
6297 Loc : constant Source_Ptr := Sloc (N);
6298 Typ : constant Entity_Id := Etype (N);
6301 Unary_Op_Validity_Checks (N);
6303 if not Backend_Overflow_Checks_On_Target
6304 and then Is_Signed_Integer_Type (Etype (N))
6305 and then Do_Overflow_Check (N)
6307 -- Software overflow checking expands -expr into (0 - expr)
6310 Make_Op_Subtract (Loc,
6311 Left_Opnd => Make_Integer_Literal (Loc, 0),
6312 Right_Opnd => Right_Opnd (N)));
6314 Analyze_And_Resolve (N, Typ);
6316 -- Vax floating-point types case
6318 elsif Vax_Float (Etype (N)) then
6319 Expand_Vax_Arith (N);
6321 end Expand_N_Op_Minus;
6323 ---------------------
6324 -- Expand_N_Op_Mod --
6325 ---------------------
6327 procedure Expand_N_Op_Mod (N : Node_Id) is
6328 Loc : constant Source_Ptr := Sloc (N);
6329 Typ : constant Entity_Id := Etype (N);
6330 Left : constant Node_Id := Left_Opnd (N);
6331 Right : constant Node_Id := Right_Opnd (N);
6332 DOC : constant Boolean := Do_Overflow_Check (N);
6333 DDC : constant Boolean := Do_Division_Check (N);
6343 pragma Warnings (Off, Lhi);
6346 Binary_Op_Validity_Checks (N);
6348 Determine_Range (Right, ROK, Rlo, Rhi, Assume_Valid => True);
6349 Determine_Range (Left, LOK, Llo, Lhi, Assume_Valid => True);
6351 -- Convert mod to rem if operands are known non-negative. We do this
6352 -- since it is quite likely that this will improve the quality of code,
6353 -- (the operation now corresponds to the hardware remainder), and it
6354 -- does not seem likely that it could be harmful.
6356 if LOK and then Llo >= 0
6358 ROK and then Rlo >= 0
6361 Make_Op_Rem (Sloc (N),
6362 Left_Opnd => Left_Opnd (N),
6363 Right_Opnd => Right_Opnd (N)));
6365 -- Instead of reanalyzing the node we do the analysis manually. This
6366 -- avoids anomalies when the replacement is done in an instance and
6367 -- is epsilon more efficient.
6369 Set_Entity (N, Standard_Entity (S_Op_Rem));
6371 Set_Do_Overflow_Check (N, DOC);
6372 Set_Do_Division_Check (N, DDC);
6373 Expand_N_Op_Rem (N);
6376 -- Otherwise, normal mod processing
6379 if Is_Integer_Type (Etype (N)) then
6380 Apply_Divide_Check (N);
6383 -- Apply optimization x mod 1 = 0. We don't really need that with
6384 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
6385 -- certainly harmless.
6387 if Is_Integer_Type (Etype (N))
6388 and then Compile_Time_Known_Value (Right)
6389 and then Expr_Value (Right) = Uint_1
6391 -- Call Remove_Side_Effects to ensure that any side effects in
6392 -- the ignored left operand (in particular function calls to
6393 -- user defined functions) are properly executed.
6395 Remove_Side_Effects (Left);
6397 Rewrite (N, Make_Integer_Literal (Loc, 0));
6398 Analyze_And_Resolve (N, Typ);
6402 -- Deal with annoying case of largest negative number remainder
6403 -- minus one. Gigi does not handle this case correctly, because
6404 -- it generates a divide instruction which may trap in this case.
6406 -- In fact the check is quite easy, if the right operand is -1, then
6407 -- the mod value is always 0, and we can just ignore the left operand
6408 -- completely in this case.
6410 -- The operand type may be private (e.g. in the expansion of an
6411 -- intrinsic operation) so we must use the underlying type to get the
6412 -- bounds, and convert the literals explicitly.
6416 (Type_Low_Bound (Base_Type (Underlying_Type (Etype (Left)))));
6418 if ((not ROK) or else (Rlo <= (-1) and then (-1) <= Rhi))
6420 ((not LOK) or else (Llo = LLB))
6423 Make_Conditional_Expression (Loc,
6424 Expressions => New_List (
6426 Left_Opnd => Duplicate_Subexpr (Right),
6428 Unchecked_Convert_To (Typ,
6429 Make_Integer_Literal (Loc, -1))),
6430 Unchecked_Convert_To (Typ,
6431 Make_Integer_Literal (Loc, Uint_0)),
6432 Relocate_Node (N))));
6434 Set_Analyzed (Next (Next (First (Expressions (N)))));
6435 Analyze_And_Resolve (N, Typ);
6438 end Expand_N_Op_Mod;
6440 --------------------------
6441 -- Expand_N_Op_Multiply --
6442 --------------------------
6444 procedure Expand_N_Op_Multiply (N : Node_Id) is
6445 Loc : constant Source_Ptr := Sloc (N);
6446 Lop : constant Node_Id := Left_Opnd (N);
6447 Rop : constant Node_Id := Right_Opnd (N);
6449 Lp2 : constant Boolean :=
6450 Nkind (Lop) = N_Op_Expon
6451 and then Is_Power_Of_2_For_Shift (Lop);
6453 Rp2 : constant Boolean :=
6454 Nkind (Rop) = N_Op_Expon
6455 and then Is_Power_Of_2_For_Shift (Rop);
6457 Ltyp : constant Entity_Id := Etype (Lop);
6458 Rtyp : constant Entity_Id := Etype (Rop);
6459 Typ : Entity_Id := Etype (N);
6462 Binary_Op_Validity_Checks (N);
6464 -- Special optimizations for integer types
6466 if Is_Integer_Type (Typ) then
6468 -- N * 0 = 0 for integer types
6470 if Compile_Time_Known_Value (Rop)
6471 and then Expr_Value (Rop) = Uint_0
6473 -- Call Remove_Side_Effects to ensure that any side effects in
6474 -- the ignored left operand (in particular function calls to
6475 -- user defined functions) are properly executed.
6477 Remove_Side_Effects (Lop);
6479 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
6480 Analyze_And_Resolve (N, Typ);
6484 -- Similar handling for 0 * N = 0
6486 if Compile_Time_Known_Value (Lop)
6487 and then Expr_Value (Lop) = Uint_0
6489 Remove_Side_Effects (Rop);
6490 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
6491 Analyze_And_Resolve (N, Typ);
6495 -- N * 1 = 1 * N = N for integer types
6497 -- This optimisation is not done if we are going to
6498 -- rewrite the product 1 * 2 ** N to a shift.
6500 if Compile_Time_Known_Value (Rop)
6501 and then Expr_Value (Rop) = Uint_1
6507 elsif Compile_Time_Known_Value (Lop)
6508 and then Expr_Value (Lop) = Uint_1
6516 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
6517 -- Is_Power_Of_2_For_Shift is set means that we know that our left
6518 -- operand is an integer, as required for this to work.
6523 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
6527 Left_Opnd => Make_Integer_Literal (Loc, 2),
6530 Left_Opnd => Right_Opnd (Lop),
6531 Right_Opnd => Right_Opnd (Rop))));
6532 Analyze_And_Resolve (N, Typ);
6537 Make_Op_Shift_Left (Loc,
6540 Convert_To (Standard_Natural, Right_Opnd (Rop))));
6541 Analyze_And_Resolve (N, Typ);
6545 -- Same processing for the operands the other way round
6549 Make_Op_Shift_Left (Loc,
6552 Convert_To (Standard_Natural, Right_Opnd (Lop))));
6553 Analyze_And_Resolve (N, Typ);
6557 -- Do required fixup of universal fixed operation
6559 if Typ = Universal_Fixed then
6560 Fixup_Universal_Fixed_Operation (N);
6564 -- Multiplications with fixed-point results
6566 if Is_Fixed_Point_Type (Typ) then
6568 -- No special processing if Treat_Fixed_As_Integer is set, since from
6569 -- a semantic point of view such operations are simply integer
6570 -- operations and will be treated that way.
6572 if not Treat_Fixed_As_Integer (N) then
6574 -- Case of fixed * integer => fixed
6576 if Is_Integer_Type (Rtyp) then
6577 Expand_Multiply_Fixed_By_Integer_Giving_Fixed (N);
6579 -- Case of integer * fixed => fixed
6581 elsif Is_Integer_Type (Ltyp) then
6582 Expand_Multiply_Integer_By_Fixed_Giving_Fixed (N);
6584 -- Case of fixed * fixed => fixed
6587 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed (N);
6591 -- Other cases of multiplication of fixed-point operands. Again we
6592 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
6594 elsif (Is_Fixed_Point_Type (Ltyp) or else Is_Fixed_Point_Type (Rtyp))
6595 and then not Treat_Fixed_As_Integer (N)
6597 if Is_Integer_Type (Typ) then
6598 Expand_Multiply_Fixed_By_Fixed_Giving_Integer (N);
6600 pragma Assert (Is_Floating_Point_Type (Typ));
6601 Expand_Multiply_Fixed_By_Fixed_Giving_Float (N);
6604 -- Mixed-mode operations can appear in a non-static universal context,
6605 -- in which case the integer argument must be converted explicitly.
6607 elsif Typ = Universal_Real
6608 and then Is_Integer_Type (Rtyp)
6610 Rewrite (Rop, Convert_To (Universal_Real, Relocate_Node (Rop)));
6612 Analyze_And_Resolve (Rop, Universal_Real);
6614 elsif Typ = Universal_Real
6615 and then Is_Integer_Type (Ltyp)
6617 Rewrite (Lop, Convert_To (Universal_Real, Relocate_Node (Lop)));
6619 Analyze_And_Resolve (Lop, Universal_Real);
6621 -- Non-fixed point cases, check software overflow checking required
6623 elsif Is_Signed_Integer_Type (Etype (N)) then
6624 Apply_Arithmetic_Overflow_Check (N);
6626 -- Deal with VAX float case
6628 elsif Vax_Float (Typ) then
6629 Expand_Vax_Arith (N);
6632 end Expand_N_Op_Multiply;
6634 --------------------
6635 -- Expand_N_Op_Ne --
6636 --------------------
6638 procedure Expand_N_Op_Ne (N : Node_Id) is
6639 Typ : constant Entity_Id := Etype (Left_Opnd (N));
6642 -- Case of elementary type with standard operator
6644 if Is_Elementary_Type (Typ)
6645 and then Sloc (Entity (N)) = Standard_Location
6647 Binary_Op_Validity_Checks (N);
6649 -- Boolean types (requiring handling of non-standard case)
6651 if Is_Boolean_Type (Typ) then
6652 Adjust_Condition (Left_Opnd (N));
6653 Adjust_Condition (Right_Opnd (N));
6654 Set_Etype (N, Standard_Boolean);
6655 Adjust_Result_Type (N, Typ);
6658 Rewrite_Comparison (N);
6660 -- If we still have comparison for Vax_Float, process it
6662 if Vax_Float (Typ) and then Nkind (N) in N_Op_Compare then
6663 Expand_Vax_Comparison (N);
6667 -- For all cases other than elementary types, we rewrite node as the
6668 -- negation of an equality operation, and reanalyze. The equality to be
6669 -- used is defined in the same scope and has the same signature. This
6670 -- signature must be set explicitly since in an instance it may not have
6671 -- the same visibility as in the generic unit. This avoids duplicating
6672 -- or factoring the complex code for record/array equality tests etc.
6676 Loc : constant Source_Ptr := Sloc (N);
6678 Ne : constant Entity_Id := Entity (N);
6681 Binary_Op_Validity_Checks (N);
6687 Left_Opnd => Left_Opnd (N),
6688 Right_Opnd => Right_Opnd (N)));
6689 Set_Paren_Count (Right_Opnd (Neg), 1);
6691 if Scope (Ne) /= Standard_Standard then
6692 Set_Entity (Right_Opnd (Neg), Corresponding_Equality (Ne));
6695 -- For navigation purposes, the inequality is treated as an
6696 -- implicit reference to the corresponding equality. Preserve the
6697 -- Comes_From_ source flag so that the proper Xref entry is
6700 Preserve_Comes_From_Source (Neg, N);
6701 Preserve_Comes_From_Source (Right_Opnd (Neg), N);
6703 Analyze_And_Resolve (N, Standard_Boolean);
6708 ---------------------
6709 -- Expand_N_Op_Not --
6710 ---------------------
6712 -- If the argument is other than a Boolean array type, there is no special
6713 -- expansion required.
6715 -- For the packed case, we call the special routine in Exp_Pakd, except
6716 -- that if the component size is greater than one, we use the standard
6717 -- routine generating a gruesome loop (it is so peculiar to have packed
6718 -- arrays with non-standard Boolean representations anyway, so it does not
6719 -- matter that we do not handle this case efficiently).
6721 -- For the unpacked case (and for the special packed case where we have non
6722 -- standard Booleans, as discussed above), we generate and insert into the
6723 -- tree the following function definition:
6725 -- function Nnnn (A : arr) is
6728 -- for J in a'range loop
6729 -- B (J) := not A (J);
6734 -- Here arr is the actual subtype of the parameter (and hence always
6735 -- constrained). Then we replace the not with a call to this function.
6737 procedure Expand_N_Op_Not (N : Node_Id) is
6738 Loc : constant Source_Ptr := Sloc (N);
6739 Typ : constant Entity_Id := Etype (N);
6748 Func_Name : Entity_Id;
6749 Loop_Statement : Node_Id;
6752 Unary_Op_Validity_Checks (N);
6754 -- For boolean operand, deal with non-standard booleans
6756 if Is_Boolean_Type (Typ) then
6757 Adjust_Condition (Right_Opnd (N));
6758 Set_Etype (N, Standard_Boolean);
6759 Adjust_Result_Type (N, Typ);
6763 -- Only array types need any other processing
6765 if not Is_Array_Type (Typ) then
6769 -- Case of array operand. If bit packed with a component size of 1,
6770 -- handle it in Exp_Pakd if the operand is known to be aligned.
6772 if Is_Bit_Packed_Array (Typ)
6773 and then Component_Size (Typ) = 1
6774 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
6776 Expand_Packed_Not (N);
6780 -- Case of array operand which is not bit-packed. If the context is
6781 -- a safe assignment, call in-place operation, If context is a larger
6782 -- boolean expression in the context of a safe assignment, expansion is
6783 -- done by enclosing operation.
6785 Opnd := Relocate_Node (Right_Opnd (N));
6786 Convert_To_Actual_Subtype (Opnd);
6787 Arr := Etype (Opnd);
6788 Ensure_Defined (Arr, N);
6789 Silly_Boolean_Array_Not_Test (N, Arr);
6791 if Nkind (Parent (N)) = N_Assignment_Statement then
6792 if Safe_In_Place_Array_Op (Name (Parent (N)), N, Empty) then
6793 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
6796 -- Special case the negation of a binary operation
6798 elsif Nkind_In (Opnd, N_Op_And, N_Op_Or, N_Op_Xor)
6799 and then Safe_In_Place_Array_Op
6800 (Name (Parent (N)), Left_Opnd (Opnd), Right_Opnd (Opnd))
6802 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
6806 elsif Nkind (Parent (N)) in N_Binary_Op
6807 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
6810 Op1 : constant Node_Id := Left_Opnd (Parent (N));
6811 Op2 : constant Node_Id := Right_Opnd (Parent (N));
6812 Lhs : constant Node_Id := Name (Parent (Parent (N)));
6815 if Safe_In_Place_Array_Op (Lhs, Op1, Op2) then
6817 and then Nkind (Op2) = N_Op_Not
6819 -- (not A) op (not B) can be reduced to a single call
6824 and then Nkind (Parent (N)) = N_Op_Xor
6826 -- A xor (not B) can also be special-cased
6834 A := Make_Defining_Identifier (Loc, Name_uA);
6835 B := Make_Defining_Identifier (Loc, Name_uB);
6836 J := Make_Defining_Identifier (Loc, Name_uJ);
6839 Make_Indexed_Component (Loc,
6840 Prefix => New_Reference_To (A, Loc),
6841 Expressions => New_List (New_Reference_To (J, Loc)));
6844 Make_Indexed_Component (Loc,
6845 Prefix => New_Reference_To (B, Loc),
6846 Expressions => New_List (New_Reference_To (J, Loc)));
6849 Make_Implicit_Loop_Statement (N,
6850 Identifier => Empty,
6853 Make_Iteration_Scheme (Loc,
6854 Loop_Parameter_Specification =>
6855 Make_Loop_Parameter_Specification (Loc,
6856 Defining_Identifier => J,
6857 Discrete_Subtype_Definition =>
6858 Make_Attribute_Reference (Loc,
6859 Prefix => Make_Identifier (Loc, Chars (A)),
6860 Attribute_Name => Name_Range))),
6862 Statements => New_List (
6863 Make_Assignment_Statement (Loc,
6865 Expression => Make_Op_Not (Loc, A_J))));
6867 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('N'));
6868 Set_Is_Inlined (Func_Name);
6871 Make_Subprogram_Body (Loc,
6873 Make_Function_Specification (Loc,
6874 Defining_Unit_Name => Func_Name,
6875 Parameter_Specifications => New_List (
6876 Make_Parameter_Specification (Loc,
6877 Defining_Identifier => A,
6878 Parameter_Type => New_Reference_To (Typ, Loc))),
6879 Result_Definition => New_Reference_To (Typ, Loc)),
6881 Declarations => New_List (
6882 Make_Object_Declaration (Loc,
6883 Defining_Identifier => B,
6884 Object_Definition => New_Reference_To (Arr, Loc))),
6886 Handled_Statement_Sequence =>
6887 Make_Handled_Sequence_Of_Statements (Loc,
6888 Statements => New_List (
6890 Make_Simple_Return_Statement (Loc,
6892 Make_Identifier (Loc, Chars (B)))))));
6895 Make_Function_Call (Loc,
6896 Name => New_Reference_To (Func_Name, Loc),
6897 Parameter_Associations => New_List (Opnd)));
6899 Analyze_And_Resolve (N, Typ);
6900 end Expand_N_Op_Not;
6902 --------------------
6903 -- Expand_N_Op_Or --
6904 --------------------
6906 procedure Expand_N_Op_Or (N : Node_Id) is
6907 Typ : constant Entity_Id := Etype (N);
6910 Binary_Op_Validity_Checks (N);
6912 if Is_Array_Type (Etype (N)) then
6913 Expand_Boolean_Operator (N);
6915 elsif Is_Boolean_Type (Etype (N)) then
6916 Adjust_Condition (Left_Opnd (N));
6917 Adjust_Condition (Right_Opnd (N));
6918 Set_Etype (N, Standard_Boolean);
6919 Adjust_Result_Type (N, Typ);
6923 ----------------------
6924 -- Expand_N_Op_Plus --
6925 ----------------------
6927 procedure Expand_N_Op_Plus (N : Node_Id) is
6929 Unary_Op_Validity_Checks (N);
6930 end Expand_N_Op_Plus;
6932 ---------------------
6933 -- Expand_N_Op_Rem --
6934 ---------------------
6936 procedure Expand_N_Op_Rem (N : Node_Id) is
6937 Loc : constant Source_Ptr := Sloc (N);
6938 Typ : constant Entity_Id := Etype (N);
6940 Left : constant Node_Id := Left_Opnd (N);
6941 Right : constant Node_Id := Right_Opnd (N);
6949 -- Set if corresponding operand can be negative
6951 pragma Unreferenced (Hi);
6954 Binary_Op_Validity_Checks (N);
6956 if Is_Integer_Type (Etype (N)) then
6957 Apply_Divide_Check (N);
6960 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
6961 -- but it is useful with other back ends (e.g. AAMP), and is certainly
6964 if Is_Integer_Type (Etype (N))
6965 and then Compile_Time_Known_Value (Right)
6966 and then Expr_Value (Right) = Uint_1
6968 -- Call Remove_Side_Effects to ensure that any side effects in the
6969 -- ignored left operand (in particular function calls to user defined
6970 -- functions) are properly executed.
6972 Remove_Side_Effects (Left);
6974 Rewrite (N, Make_Integer_Literal (Loc, 0));
6975 Analyze_And_Resolve (N, Typ);
6979 -- Deal with annoying case of largest negative number remainder minus
6980 -- one. Gigi does not handle this case correctly, because it generates
6981 -- a divide instruction which may trap in this case.
6983 -- In fact the check is quite easy, if the right operand is -1, then
6984 -- the remainder is always 0, and we can just ignore the left operand
6985 -- completely in this case.
6987 Determine_Range (Right, OK, Lo, Hi, Assume_Valid => True);
6988 Lneg := (not OK) or else Lo < 0;
6990 Determine_Range (Left, OK, Lo, Hi, Assume_Valid => True);
6991 Rneg := (not OK) or else Lo < 0;
6993 -- We won't mess with trying to find out if the left operand can really
6994 -- be the largest negative number (that's a pain in the case of private
6995 -- types and this is really marginal). We will just assume that we need
6996 -- the test if the left operand can be negative at all.
6998 if Lneg and Rneg then
7000 Make_Conditional_Expression (Loc,
7001 Expressions => New_List (
7003 Left_Opnd => Duplicate_Subexpr (Right),
7005 Unchecked_Convert_To (Typ,
7006 Make_Integer_Literal (Loc, -1))),
7008 Unchecked_Convert_To (Typ,
7009 Make_Integer_Literal (Loc, Uint_0)),
7011 Relocate_Node (N))));
7013 Set_Analyzed (Next (Next (First (Expressions (N)))));
7014 Analyze_And_Resolve (N, Typ);
7016 end Expand_N_Op_Rem;
7018 -----------------------------
7019 -- Expand_N_Op_Rotate_Left --
7020 -----------------------------
7022 procedure Expand_N_Op_Rotate_Left (N : Node_Id) is
7024 Binary_Op_Validity_Checks (N);
7025 end Expand_N_Op_Rotate_Left;
7027 ------------------------------
7028 -- Expand_N_Op_Rotate_Right --
7029 ------------------------------
7031 procedure Expand_N_Op_Rotate_Right (N : Node_Id) is
7033 Binary_Op_Validity_Checks (N);
7034 end Expand_N_Op_Rotate_Right;
7036 ----------------------------
7037 -- Expand_N_Op_Shift_Left --
7038 ----------------------------
7040 procedure Expand_N_Op_Shift_Left (N : Node_Id) is
7042 Binary_Op_Validity_Checks (N);
7043 end Expand_N_Op_Shift_Left;
7045 -----------------------------
7046 -- Expand_N_Op_Shift_Right --
7047 -----------------------------
7049 procedure Expand_N_Op_Shift_Right (N : Node_Id) is
7051 Binary_Op_Validity_Checks (N);
7052 end Expand_N_Op_Shift_Right;
7054 ----------------------------------------
7055 -- Expand_N_Op_Shift_Right_Arithmetic --
7056 ----------------------------------------
7058 procedure Expand_N_Op_Shift_Right_Arithmetic (N : Node_Id) is
7060 Binary_Op_Validity_Checks (N);
7061 end Expand_N_Op_Shift_Right_Arithmetic;
7063 --------------------------
7064 -- Expand_N_Op_Subtract --
7065 --------------------------
7067 procedure Expand_N_Op_Subtract (N : Node_Id) is
7068 Typ : constant Entity_Id := Etype (N);
7071 Binary_Op_Validity_Checks (N);
7073 -- N - 0 = N for integer types
7075 if Is_Integer_Type (Typ)
7076 and then Compile_Time_Known_Value (Right_Opnd (N))
7077 and then Expr_Value (Right_Opnd (N)) = 0
7079 Rewrite (N, Left_Opnd (N));
7083 -- Arithmetic overflow checks for signed integer/fixed point types
7085 if Is_Signed_Integer_Type (Typ)
7086 or else Is_Fixed_Point_Type (Typ)
7088 Apply_Arithmetic_Overflow_Check (N);
7090 -- Vax floating-point types case
7092 elsif Vax_Float (Typ) then
7093 Expand_Vax_Arith (N);
7095 end Expand_N_Op_Subtract;
7097 ---------------------
7098 -- Expand_N_Op_Xor --
7099 ---------------------
7101 procedure Expand_N_Op_Xor (N : Node_Id) is
7102 Typ : constant Entity_Id := Etype (N);
7105 Binary_Op_Validity_Checks (N);
7107 if Is_Array_Type (Etype (N)) then
7108 Expand_Boolean_Operator (N);
7110 elsif Is_Boolean_Type (Etype (N)) then
7111 Adjust_Condition (Left_Opnd (N));
7112 Adjust_Condition (Right_Opnd (N));
7113 Set_Etype (N, Standard_Boolean);
7114 Adjust_Result_Type (N, Typ);
7116 end Expand_N_Op_Xor;
7118 ----------------------
7119 -- Expand_N_Or_Else --
7120 ----------------------
7122 -- Expand into conditional expression if Actions present, and also
7123 -- deal with optimizing case of arguments being True or False.
7125 procedure Expand_N_Or_Else (N : Node_Id) is
7126 Loc : constant Source_Ptr := Sloc (N);
7127 Typ : constant Entity_Id := Etype (N);
7128 Left : constant Node_Id := Left_Opnd (N);
7129 Right : constant Node_Id := Right_Opnd (N);
7133 -- Deal with non-standard booleans
7135 if Is_Boolean_Type (Typ) then
7136 Adjust_Condition (Left);
7137 Adjust_Condition (Right);
7138 Set_Etype (N, Standard_Boolean);
7141 -- Check for cases where left argument is known to be True or False
7143 if Compile_Time_Known_Value (Left) then
7145 -- If left argument is False, change (False or else Right) to Right.
7146 -- Any actions associated with Right will be executed unconditionally
7147 -- and can thus be inserted into the tree unconditionally.
7149 if Expr_Value_E (Left) = Standard_False then
7150 if Present (Actions (N)) then
7151 Insert_Actions (N, Actions (N));
7156 -- If left argument is True, change (True and then Right) to True. In
7157 -- this case we can forget the actions associated with Right, since
7158 -- they will never be executed.
7160 else pragma Assert (Expr_Value_E (Left) = Standard_True);
7161 Kill_Dead_Code (Right);
7162 Kill_Dead_Code (Actions (N));
7163 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
7166 Adjust_Result_Type (N, Typ);
7170 -- If Actions are present, we expand
7172 -- left or else right
7176 -- if left then True else right end
7178 -- with the actions becoming the Else_Actions of the conditional
7179 -- expression. This conditional expression is then further expanded
7180 -- (and will eventually disappear)
7182 if Present (Actions (N)) then
7183 Actlist := Actions (N);
7185 Make_Conditional_Expression (Loc,
7186 Expressions => New_List (
7188 New_Occurrence_Of (Standard_True, Loc),
7191 Set_Else_Actions (N, Actlist);
7192 Analyze_And_Resolve (N, Standard_Boolean);
7193 Adjust_Result_Type (N, Typ);
7197 -- No actions present, check for cases of right argument True/False
7199 if Compile_Time_Known_Value (Right) then
7201 -- Change (Left or else False) to Left. Note that we know there are
7202 -- no actions associated with the True operand, since we just checked
7203 -- for this case above.
7205 if Expr_Value_E (Right) = Standard_False then
7208 -- Change (Left or else True) to True, making sure to preserve any
7209 -- side effects associated with the Left operand.
7211 else pragma Assert (Expr_Value_E (Right) = Standard_True);
7212 Remove_Side_Effects (Left);
7214 (N, New_Occurrence_Of (Standard_True, Loc));
7218 Adjust_Result_Type (N, Typ);
7219 end Expand_N_Or_Else;
7221 -----------------------------------
7222 -- Expand_N_Qualified_Expression --
7223 -----------------------------------
7225 procedure Expand_N_Qualified_Expression (N : Node_Id) is
7226 Operand : constant Node_Id := Expression (N);
7227 Target_Type : constant Entity_Id := Entity (Subtype_Mark (N));
7230 -- Do validity check if validity checking operands
7232 if Validity_Checks_On
7233 and then Validity_Check_Operands
7235 Ensure_Valid (Operand);
7238 -- Apply possible constraint check
7240 Apply_Constraint_Check (Operand, Target_Type, No_Sliding => True);
7242 if Do_Range_Check (Operand) then
7243 Set_Do_Range_Check (Operand, False);
7244 Generate_Range_Check (Operand, Target_Type, CE_Range_Check_Failed);
7246 end Expand_N_Qualified_Expression;
7248 ---------------------------------
7249 -- Expand_N_Selected_Component --
7250 ---------------------------------
7252 -- If the selector is a discriminant of a concurrent object, rewrite the
7253 -- prefix to denote the corresponding record type.
7255 procedure Expand_N_Selected_Component (N : Node_Id) is
7256 Loc : constant Source_Ptr := Sloc (N);
7257 Par : constant Node_Id := Parent (N);
7258 P : constant Node_Id := Prefix (N);
7259 Ptyp : Entity_Id := Underlying_Type (Etype (P));
7264 function In_Left_Hand_Side (Comp : Node_Id) return Boolean;
7265 -- Gigi needs a temporary for prefixes that depend on a discriminant,
7266 -- unless the context of an assignment can provide size information.
7267 -- Don't we have a general routine that does this???
7269 -----------------------
7270 -- In_Left_Hand_Side --
7271 -----------------------
7273 function In_Left_Hand_Side (Comp : Node_Id) return Boolean is
7275 return (Nkind (Parent (Comp)) = N_Assignment_Statement
7276 and then Comp = Name (Parent (Comp)))
7277 or else (Present (Parent (Comp))
7278 and then Nkind (Parent (Comp)) in N_Subexpr
7279 and then In_Left_Hand_Side (Parent (Comp)));
7280 end In_Left_Hand_Side;
7282 -- Start of processing for Expand_N_Selected_Component
7285 -- Insert explicit dereference if required
7287 if Is_Access_Type (Ptyp) then
7288 Insert_Explicit_Dereference (P);
7289 Analyze_And_Resolve (P, Designated_Type (Ptyp));
7291 if Ekind (Etype (P)) = E_Private_Subtype
7292 and then Is_For_Access_Subtype (Etype (P))
7294 Set_Etype (P, Base_Type (Etype (P)));
7300 -- Deal with discriminant check required
7302 if Do_Discriminant_Check (N) then
7304 -- Present the discriminant checking function to the backend, so that
7305 -- it can inline the call to the function.
7308 (Discriminant_Checking_Func
7309 (Original_Record_Component (Entity (Selector_Name (N)))));
7311 -- Now reset the flag and generate the call
7313 Set_Do_Discriminant_Check (N, False);
7314 Generate_Discriminant_Check (N);
7317 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7318 -- function, then additional actuals must be passed.
7320 if Ada_Version >= Ada_05
7321 and then Is_Build_In_Place_Function_Call (P)
7323 Make_Build_In_Place_Call_In_Anonymous_Context (P);
7326 -- Gigi cannot handle unchecked conversions that are the prefix of a
7327 -- selected component with discriminants. This must be checked during
7328 -- expansion, because during analysis the type of the selector is not
7329 -- known at the point the prefix is analyzed. If the conversion is the
7330 -- target of an assignment, then we cannot force the evaluation.
7332 if Nkind (Prefix (N)) = N_Unchecked_Type_Conversion
7333 and then Has_Discriminants (Etype (N))
7334 and then not In_Left_Hand_Side (N)
7336 Force_Evaluation (Prefix (N));
7339 -- Remaining processing applies only if selector is a discriminant
7341 if Ekind (Entity (Selector_Name (N))) = E_Discriminant then
7343 -- If the selector is a discriminant of a constrained record type,
7344 -- we may be able to rewrite the expression with the actual value
7345 -- of the discriminant, a useful optimization in some cases.
7347 if Is_Record_Type (Ptyp)
7348 and then Has_Discriminants (Ptyp)
7349 and then Is_Constrained (Ptyp)
7351 -- Do this optimization for discrete types only, and not for
7352 -- access types (access discriminants get us into trouble!)
7354 if not Is_Discrete_Type (Etype (N)) then
7357 -- Don't do this on the left hand of an assignment statement.
7358 -- Normally one would think that references like this would
7359 -- not occur, but they do in generated code, and mean that
7360 -- we really do want to assign the discriminant!
7362 elsif Nkind (Par) = N_Assignment_Statement
7363 and then Name (Par) = N
7367 -- Don't do this optimization for the prefix of an attribute or
7368 -- the operand of an object renaming declaration since these are
7369 -- contexts where we do not want the value anyway.
7371 elsif (Nkind (Par) = N_Attribute_Reference
7372 and then Prefix (Par) = N)
7373 or else Is_Renamed_Object (N)
7377 -- Don't do this optimization if we are within the code for a
7378 -- discriminant check, since the whole point of such a check may
7379 -- be to verify the condition on which the code below depends!
7381 elsif Is_In_Discriminant_Check (N) then
7384 -- Green light to see if we can do the optimization. There is
7385 -- still one condition that inhibits the optimization below but
7386 -- now is the time to check the particular discriminant.
7389 -- Loop through discriminants to find the matching discriminant
7390 -- constraint to see if we can copy it.
7392 Disc := First_Discriminant (Ptyp);
7393 Dcon := First_Elmt (Discriminant_Constraint (Ptyp));
7394 Discr_Loop : while Present (Dcon) loop
7396 -- Check if this is the matching discriminant
7398 if Disc = Entity (Selector_Name (N)) then
7400 -- Here we have the matching discriminant. Check for
7401 -- the case of a discriminant of a component that is
7402 -- constrained by an outer discriminant, which cannot
7403 -- be optimized away.
7406 Denotes_Discriminant
7407 (Node (Dcon), Check_Concurrent => True)
7411 -- In the context of a case statement, the expression may
7412 -- have the base type of the discriminant, and we need to
7413 -- preserve the constraint to avoid spurious errors on
7416 elsif Nkind (Parent (N)) = N_Case_Statement
7417 and then Etype (Node (Dcon)) /= Etype (Disc)
7420 Make_Qualified_Expression (Loc,
7422 New_Occurrence_Of (Etype (Disc), Loc),
7424 New_Copy_Tree (Node (Dcon))));
7425 Analyze_And_Resolve (N, Etype (Disc));
7427 -- In case that comes out as a static expression,
7428 -- reset it (a selected component is never static).
7430 Set_Is_Static_Expression (N, False);
7433 -- Otherwise we can just copy the constraint, but the
7434 -- result is certainly not static! In some cases the
7435 -- discriminant constraint has been analyzed in the
7436 -- context of the original subtype indication, but for
7437 -- itypes the constraint might not have been analyzed
7438 -- yet, and this must be done now.
7441 Rewrite (N, New_Copy_Tree (Node (Dcon)));
7442 Analyze_And_Resolve (N);
7443 Set_Is_Static_Expression (N, False);
7449 Next_Discriminant (Disc);
7450 end loop Discr_Loop;
7452 -- Note: the above loop should always find a matching
7453 -- discriminant, but if it does not, we just missed an
7454 -- optimization due to some glitch (perhaps a previous error),
7460 -- The only remaining processing is in the case of a discriminant of
7461 -- a concurrent object, where we rewrite the prefix to denote the
7462 -- corresponding record type. If the type is derived and has renamed
7463 -- discriminants, use corresponding discriminant, which is the one
7464 -- that appears in the corresponding record.
7466 if not Is_Concurrent_Type (Ptyp) then
7470 Disc := Entity (Selector_Name (N));
7472 if Is_Derived_Type (Ptyp)
7473 and then Present (Corresponding_Discriminant (Disc))
7475 Disc := Corresponding_Discriminant (Disc);
7479 Make_Selected_Component (Loc,
7481 Unchecked_Convert_To (Corresponding_Record_Type (Ptyp),
7483 Selector_Name => Make_Identifier (Loc, Chars (Disc)));
7488 end Expand_N_Selected_Component;
7490 --------------------
7491 -- Expand_N_Slice --
7492 --------------------
7494 procedure Expand_N_Slice (N : Node_Id) is
7495 Loc : constant Source_Ptr := Sloc (N);
7496 Typ : constant Entity_Id := Etype (N);
7497 Pfx : constant Node_Id := Prefix (N);
7498 Ptp : Entity_Id := Etype (Pfx);
7500 function Is_Procedure_Actual (N : Node_Id) return Boolean;
7501 -- Check whether the argument is an actual for a procedure call, in
7502 -- which case the expansion of a bit-packed slice is deferred until the
7503 -- call itself is expanded. The reason this is required is that we might
7504 -- have an IN OUT or OUT parameter, and the copy out is essential, and
7505 -- that copy out would be missed if we created a temporary here in
7506 -- Expand_N_Slice. Note that we don't bother to test specifically for an
7507 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
7508 -- is harmless to defer expansion in the IN case, since the call
7509 -- processing will still generate the appropriate copy in operation,
7510 -- which will take care of the slice.
7512 procedure Make_Temporary_For_Slice;
7513 -- Create a named variable for the value of the slice, in cases where
7514 -- the back-end cannot handle it properly, e.g. when packed types or
7515 -- unaligned slices are involved.
7517 -------------------------
7518 -- Is_Procedure_Actual --
7519 -------------------------
7521 function Is_Procedure_Actual (N : Node_Id) return Boolean is
7522 Par : Node_Id := Parent (N);
7526 -- If our parent is a procedure call we can return
7528 if Nkind (Par) = N_Procedure_Call_Statement then
7531 -- If our parent is a type conversion, keep climbing the tree,
7532 -- since a type conversion can be a procedure actual. Also keep
7533 -- climbing if parameter association or a qualified expression,
7534 -- since these are additional cases that do can appear on
7535 -- procedure actuals.
7537 elsif Nkind_In (Par, N_Type_Conversion,
7538 N_Parameter_Association,
7539 N_Qualified_Expression)
7541 Par := Parent (Par);
7543 -- Any other case is not what we are looking for
7549 end Is_Procedure_Actual;
7551 ------------------------------
7552 -- Make_Temporary_For_Slice --
7553 ------------------------------
7555 procedure Make_Temporary_For_Slice is
7557 Ent : constant Entity_Id := Make_Temporary (Loc, 'T', N);
7560 Make_Object_Declaration (Loc,
7561 Defining_Identifier => Ent,
7562 Object_Definition => New_Occurrence_Of (Typ, Loc));
7564 Set_No_Initialization (Decl);
7566 Insert_Actions (N, New_List (
7568 Make_Assignment_Statement (Loc,
7569 Name => New_Occurrence_Of (Ent, Loc),
7570 Expression => Relocate_Node (N))));
7572 Rewrite (N, New_Occurrence_Of (Ent, Loc));
7573 Analyze_And_Resolve (N, Typ);
7574 end Make_Temporary_For_Slice;
7576 -- Start of processing for Expand_N_Slice
7579 -- Special handling for access types
7581 if Is_Access_Type (Ptp) then
7583 Ptp := Designated_Type (Ptp);
7586 Make_Explicit_Dereference (Sloc (N),
7587 Prefix => Relocate_Node (Pfx)));
7589 Analyze_And_Resolve (Pfx, Ptp);
7592 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7593 -- function, then additional actuals must be passed.
7595 if Ada_Version >= Ada_05
7596 and then Is_Build_In_Place_Function_Call (Pfx)
7598 Make_Build_In_Place_Call_In_Anonymous_Context (Pfx);
7601 -- The remaining case to be handled is packed slices. We can leave
7602 -- packed slices as they are in the following situations:
7604 -- 1. Right or left side of an assignment (we can handle this
7605 -- situation correctly in the assignment statement expansion).
7607 -- 2. Prefix of indexed component (the slide is optimized away in this
7608 -- case, see the start of Expand_N_Slice.)
7610 -- 3. Object renaming declaration, since we want the name of the
7611 -- slice, not the value.
7613 -- 4. Argument to procedure call, since copy-in/copy-out handling may
7614 -- be required, and this is handled in the expansion of call
7617 -- 5. Prefix of an address attribute (this is an error which is caught
7618 -- elsewhere, and the expansion would interfere with generating the
7621 if not Is_Packed (Typ) then
7623 -- Apply transformation for actuals of a function call, where
7624 -- Expand_Actuals is not used.
7626 if Nkind (Parent (N)) = N_Function_Call
7627 and then Is_Possibly_Unaligned_Slice (N)
7629 Make_Temporary_For_Slice;
7632 elsif Nkind (Parent (N)) = N_Assignment_Statement
7633 or else (Nkind (Parent (Parent (N))) = N_Assignment_Statement
7634 and then Parent (N) = Name (Parent (Parent (N))))
7638 elsif Nkind (Parent (N)) = N_Indexed_Component
7639 or else Is_Renamed_Object (N)
7640 or else Is_Procedure_Actual (N)
7644 elsif Nkind (Parent (N)) = N_Attribute_Reference
7645 and then Attribute_Name (Parent (N)) = Name_Address
7650 Make_Temporary_For_Slice;
7654 ------------------------------
7655 -- Expand_N_Type_Conversion --
7656 ------------------------------
7658 procedure Expand_N_Type_Conversion (N : Node_Id) is
7659 Loc : constant Source_Ptr := Sloc (N);
7660 Operand : constant Node_Id := Expression (N);
7661 Target_Type : constant Entity_Id := Etype (N);
7662 Operand_Type : Entity_Id := Etype (Operand);
7664 procedure Handle_Changed_Representation;
7665 -- This is called in the case of record and array type conversions to
7666 -- see if there is a change of representation to be handled. Change of
7667 -- representation is actually handled at the assignment statement level,
7668 -- and what this procedure does is rewrite node N conversion as an
7669 -- assignment to temporary. If there is no change of representation,
7670 -- then the conversion node is unchanged.
7672 procedure Raise_Accessibility_Error;
7673 -- Called when we know that an accessibility check will fail. Rewrites
7674 -- node N to an appropriate raise statement and outputs warning msgs.
7675 -- The Etype of the raise node is set to Target_Type.
7677 procedure Real_Range_Check;
7678 -- Handles generation of range check for real target value
7680 -----------------------------------
7681 -- Handle_Changed_Representation --
7682 -----------------------------------
7684 procedure Handle_Changed_Representation is
7694 -- Nothing else to do if no change of representation
7696 if Same_Representation (Operand_Type, Target_Type) then
7699 -- The real change of representation work is done by the assignment
7700 -- statement processing. So if this type conversion is appearing as
7701 -- the expression of an assignment statement, nothing needs to be
7702 -- done to the conversion.
7704 elsif Nkind (Parent (N)) = N_Assignment_Statement then
7707 -- Otherwise we need to generate a temporary variable, and do the
7708 -- change of representation assignment into that temporary variable.
7709 -- The conversion is then replaced by a reference to this variable.
7714 -- If type is unconstrained we have to add a constraint, copied
7715 -- from the actual value of the left hand side.
7717 if not Is_Constrained (Target_Type) then
7718 if Has_Discriminants (Operand_Type) then
7719 Disc := First_Discriminant (Operand_Type);
7721 if Disc /= First_Stored_Discriminant (Operand_Type) then
7722 Disc := First_Stored_Discriminant (Operand_Type);
7726 while Present (Disc) loop
7728 Make_Selected_Component (Loc,
7729 Prefix => Duplicate_Subexpr_Move_Checks (Operand),
7731 Make_Identifier (Loc, Chars (Disc))));
7732 Next_Discriminant (Disc);
7735 elsif Is_Array_Type (Operand_Type) then
7736 N_Ix := First_Index (Target_Type);
7739 for J in 1 .. Number_Dimensions (Operand_Type) loop
7741 -- We convert the bounds explicitly. We use an unchecked
7742 -- conversion because bounds checks are done elsewhere.
7747 Unchecked_Convert_To (Etype (N_Ix),
7748 Make_Attribute_Reference (Loc,
7750 Duplicate_Subexpr_No_Checks
7751 (Operand, Name_Req => True),
7752 Attribute_Name => Name_First,
7753 Expressions => New_List (
7754 Make_Integer_Literal (Loc, J)))),
7757 Unchecked_Convert_To (Etype (N_Ix),
7758 Make_Attribute_Reference (Loc,
7760 Duplicate_Subexpr_No_Checks
7761 (Operand, Name_Req => True),
7762 Attribute_Name => Name_Last,
7763 Expressions => New_List (
7764 Make_Integer_Literal (Loc, J))))));
7771 Odef := New_Occurrence_Of (Target_Type, Loc);
7773 if Present (Cons) then
7775 Make_Subtype_Indication (Loc,
7776 Subtype_Mark => Odef,
7778 Make_Index_Or_Discriminant_Constraint (Loc,
7779 Constraints => Cons));
7782 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
7784 Make_Object_Declaration (Loc,
7785 Defining_Identifier => Temp,
7786 Object_Definition => Odef);
7788 Set_No_Initialization (Decl, True);
7790 -- Insert required actions. It is essential to suppress checks
7791 -- since we have suppressed default initialization, which means
7792 -- that the variable we create may have no discriminants.
7797 Make_Assignment_Statement (Loc,
7798 Name => New_Occurrence_Of (Temp, Loc),
7799 Expression => Relocate_Node (N))),
7800 Suppress => All_Checks);
7802 Rewrite (N, New_Occurrence_Of (Temp, Loc));
7805 end Handle_Changed_Representation;
7807 -------------------------------
7808 -- Raise_Accessibility_Error --
7809 -------------------------------
7811 procedure Raise_Accessibility_Error is
7814 Make_Raise_Program_Error (Sloc (N),
7815 Reason => PE_Accessibility_Check_Failed));
7816 Set_Etype (N, Target_Type);
7818 Error_Msg_N ("?accessibility check failure", N);
7820 ("\?& will be raised at run time", N, Standard_Program_Error);
7821 end Raise_Accessibility_Error;
7823 ----------------------
7824 -- Real_Range_Check --
7825 ----------------------
7827 -- Case of conversions to floating-point or fixed-point. If range checks
7828 -- are enabled and the target type has a range constraint, we convert:
7834 -- Tnn : typ'Base := typ'Base (x);
7835 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
7838 -- This is necessary when there is a conversion of integer to float or
7839 -- to fixed-point to ensure that the correct checks are made. It is not
7840 -- necessary for float to float where it is enough to simply set the
7841 -- Do_Range_Check flag.
7843 procedure Real_Range_Check is
7844 Btyp : constant Entity_Id := Base_Type (Target_Type);
7845 Lo : constant Node_Id := Type_Low_Bound (Target_Type);
7846 Hi : constant Node_Id := Type_High_Bound (Target_Type);
7847 Xtyp : constant Entity_Id := Etype (Operand);
7852 -- Nothing to do if conversion was rewritten
7854 if Nkind (N) /= N_Type_Conversion then
7858 -- Nothing to do if range checks suppressed, or target has the same
7859 -- range as the base type (or is the base type).
7861 if Range_Checks_Suppressed (Target_Type)
7862 or else (Lo = Type_Low_Bound (Btyp)
7864 Hi = Type_High_Bound (Btyp))
7869 -- Nothing to do if expression is an entity on which checks have been
7872 if Is_Entity_Name (Operand)
7873 and then Range_Checks_Suppressed (Entity (Operand))
7878 -- Nothing to do if bounds are all static and we can tell that the
7879 -- expression is within the bounds of the target. Note that if the
7880 -- operand is of an unconstrained floating-point type, then we do
7881 -- not trust it to be in range (might be infinite)
7884 S_Lo : constant Node_Id := Type_Low_Bound (Xtyp);
7885 S_Hi : constant Node_Id := Type_High_Bound (Xtyp);
7888 if (not Is_Floating_Point_Type (Xtyp)
7889 or else Is_Constrained (Xtyp))
7890 and then Compile_Time_Known_Value (S_Lo)
7891 and then Compile_Time_Known_Value (S_Hi)
7892 and then Compile_Time_Known_Value (Hi)
7893 and then Compile_Time_Known_Value (Lo)
7896 D_Lov : constant Ureal := Expr_Value_R (Lo);
7897 D_Hiv : constant Ureal := Expr_Value_R (Hi);
7902 if Is_Real_Type (Xtyp) then
7903 S_Lov := Expr_Value_R (S_Lo);
7904 S_Hiv := Expr_Value_R (S_Hi);
7906 S_Lov := UR_From_Uint (Expr_Value (S_Lo));
7907 S_Hiv := UR_From_Uint (Expr_Value (S_Hi));
7911 and then S_Lov >= D_Lov
7912 and then S_Hiv <= D_Hiv
7914 Set_Do_Range_Check (Operand, False);
7921 -- For float to float conversions, we are done
7923 if Is_Floating_Point_Type (Xtyp)
7925 Is_Floating_Point_Type (Btyp)
7930 -- Otherwise rewrite the conversion as described above
7932 Conv := Relocate_Node (N);
7933 Rewrite (Subtype_Mark (Conv), New_Occurrence_Of (Btyp, Loc));
7934 Set_Etype (Conv, Btyp);
7936 -- Enable overflow except for case of integer to float conversions,
7937 -- where it is never required, since we can never have overflow in
7940 if not Is_Integer_Type (Etype (Operand)) then
7941 Enable_Overflow_Check (Conv);
7945 Make_Defining_Identifier (Loc,
7946 Chars => New_Internal_Name ('T'));
7948 Insert_Actions (N, New_List (
7949 Make_Object_Declaration (Loc,
7950 Defining_Identifier => Tnn,
7951 Object_Definition => New_Occurrence_Of (Btyp, Loc),
7952 Expression => Conv),
7954 Make_Raise_Constraint_Error (Loc,
7959 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
7961 Make_Attribute_Reference (Loc,
7962 Attribute_Name => Name_First,
7964 New_Occurrence_Of (Target_Type, Loc))),
7968 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
7970 Make_Attribute_Reference (Loc,
7971 Attribute_Name => Name_Last,
7973 New_Occurrence_Of (Target_Type, Loc)))),
7974 Reason => CE_Range_Check_Failed)));
7976 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
7977 Analyze_And_Resolve (N, Btyp);
7978 end Real_Range_Check;
7980 -- Start of processing for Expand_N_Type_Conversion
7983 -- Nothing at all to do if conversion is to the identical type so remove
7984 -- the conversion completely, it is useless, except that it may carry
7985 -- an Assignment_OK attribute, which must be propagated to the operand.
7987 if Operand_Type = Target_Type then
7988 if Assignment_OK (N) then
7989 Set_Assignment_OK (Operand);
7992 Rewrite (N, Relocate_Node (Operand));
7996 -- Nothing to do if this is the second argument of read. This is a
7997 -- "backwards" conversion that will be handled by the specialized code
7998 -- in attribute processing.
8000 if Nkind (Parent (N)) = N_Attribute_Reference
8001 and then Attribute_Name (Parent (N)) = Name_Read
8002 and then Next (First (Expressions (Parent (N)))) = N
8007 -- Here if we may need to expand conversion
8009 -- If the operand of the type conversion is an arithmetic operation on
8010 -- signed integers, and the based type of the signed integer type in
8011 -- question is smaller than Standard.Integer, we promote both of the
8012 -- operands to type Integer.
8014 -- For example, if we have
8016 -- target-type (opnd1 + opnd2)
8018 -- and opnd1 and opnd2 are of type short integer, then we rewrite
8021 -- target-type (integer(opnd1) + integer(opnd2))
8023 -- We do this because we are always allowed to compute in a larger type
8024 -- if we do the right thing with the result, and in this case we are
8025 -- going to do a conversion which will do an appropriate check to make
8026 -- sure that things are in range of the target type in any case. This
8027 -- avoids some unnecessary intermediate overflows.
8029 -- We might consider a similar transformation in the case where the
8030 -- target is a real type or a 64-bit integer type, and the operand
8031 -- is an arithmetic operation using a 32-bit integer type. However,
8032 -- we do not bother with this case, because it could cause significant
8033 -- ineffiencies on 32-bit machines. On a 64-bit machine it would be
8034 -- much cheaper, but we don't want different behavior on 32-bit and
8035 -- 64-bit machines. Note that the exclusion of the 64-bit case also
8036 -- handles the configurable run-time cases where 64-bit arithmetic
8037 -- may simply be unavailable.
8039 -- Note: this circuit is partially redundant with respect to the circuit
8040 -- in Checks.Apply_Arithmetic_Overflow_Check, but we catch more cases in
8041 -- the processing here. Also we still need the Checks circuit, since we
8042 -- have to be sure not to generate junk overflow checks in the first
8043 -- place, since it would be trick to remove them here!
8045 if Integer_Promotion_Possible (N) then
8047 -- All conditions met, go ahead with transformation
8055 Make_Type_Conversion (Loc,
8056 Subtype_Mark => New_Reference_To (Standard_Integer, Loc),
8057 Expression => Relocate_Node (Right_Opnd (Operand)));
8059 Opnd := New_Op_Node (Nkind (Operand), Loc);
8060 Set_Right_Opnd (Opnd, R);
8062 if Nkind (Operand) in N_Binary_Op then
8064 Make_Type_Conversion (Loc,
8065 Subtype_Mark => New_Reference_To (Standard_Integer, Loc),
8066 Expression => Relocate_Node (Left_Opnd (Operand)));
8068 Set_Left_Opnd (Opnd, L);
8072 Make_Type_Conversion (Loc,
8073 Subtype_Mark => Relocate_Node (Subtype_Mark (N)),
8074 Expression => Opnd));
8076 Analyze_And_Resolve (N, Target_Type);
8081 -- Do validity check if validity checking operands
8083 if Validity_Checks_On
8084 and then Validity_Check_Operands
8086 Ensure_Valid (Operand);
8089 -- Special case of converting from non-standard boolean type
8091 if Is_Boolean_Type (Operand_Type)
8092 and then (Nonzero_Is_True (Operand_Type))
8094 Adjust_Condition (Operand);
8095 Set_Etype (Operand, Standard_Boolean);
8096 Operand_Type := Standard_Boolean;
8099 -- Case of converting to an access type
8101 if Is_Access_Type (Target_Type) then
8103 -- Apply an accessibility check when the conversion operand is an
8104 -- access parameter (or a renaming thereof), unless conversion was
8105 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
8106 -- Note that other checks may still need to be applied below (such
8107 -- as tagged type checks).
8109 if Is_Entity_Name (Operand)
8111 (Is_Formal (Entity (Operand))
8113 (Present (Renamed_Object (Entity (Operand)))
8114 and then Is_Entity_Name (Renamed_Object (Entity (Operand)))
8116 (Entity (Renamed_Object (Entity (Operand))))))
8117 and then Ekind (Etype (Operand)) = E_Anonymous_Access_Type
8118 and then (Nkind (Original_Node (N)) /= N_Attribute_Reference
8119 or else Attribute_Name (Original_Node (N)) = Name_Access)
8121 Apply_Accessibility_Check
8122 (Operand, Target_Type, Insert_Node => Operand);
8124 -- If the level of the operand type is statically deeper than the
8125 -- level of the target type, then force Program_Error. Note that this
8126 -- can only occur for cases where the attribute is within the body of
8127 -- an instantiation (otherwise the conversion will already have been
8128 -- rejected as illegal). Note: warnings are issued by the analyzer
8129 -- for the instance cases.
8131 elsif In_Instance_Body
8132 and then Type_Access_Level (Operand_Type) >
8133 Type_Access_Level (Target_Type)
8135 Raise_Accessibility_Error;
8137 -- When the operand is a selected access discriminant the check needs
8138 -- to be made against the level of the object denoted by the prefix
8139 -- of the selected name. Force Program_Error for this case as well
8140 -- (this accessibility violation can only happen if within the body
8141 -- of an instantiation).
8143 elsif In_Instance_Body
8144 and then Ekind (Operand_Type) = E_Anonymous_Access_Type
8145 and then Nkind (Operand) = N_Selected_Component
8146 and then Object_Access_Level (Operand) >
8147 Type_Access_Level (Target_Type)
8149 Raise_Accessibility_Error;
8154 -- Case of conversions of tagged types and access to tagged types
8156 -- When needed, that is to say when the expression is class-wide, Add
8157 -- runtime a tag check for (strict) downward conversion by using the
8158 -- membership test, generating:
8160 -- [constraint_error when Operand not in Target_Type'Class]
8162 -- or in the access type case
8164 -- [constraint_error
8165 -- when Operand /= null
8166 -- and then Operand.all not in
8167 -- Designated_Type (Target_Type)'Class]
8169 if (Is_Access_Type (Target_Type)
8170 and then Is_Tagged_Type (Designated_Type (Target_Type)))
8171 or else Is_Tagged_Type (Target_Type)
8173 -- Do not do any expansion in the access type case if the parent is a
8174 -- renaming, since this is an error situation which will be caught by
8175 -- Sem_Ch8, and the expansion can interfere with this error check.
8177 if Is_Access_Type (Target_Type)
8178 and then Is_Renamed_Object (N)
8183 -- Otherwise, proceed with processing tagged conversion
8186 Actual_Op_Typ : Entity_Id;
8187 Actual_Targ_Typ : Entity_Id;
8188 Make_Conversion : Boolean := False;
8189 Root_Op_Typ : Entity_Id;
8191 procedure Make_Tag_Check (Targ_Typ : Entity_Id);
8192 -- Create a membership check to test whether Operand is a member
8193 -- of Targ_Typ. If the original Target_Type is an access, include
8194 -- a test for null value. The check is inserted at N.
8196 --------------------
8197 -- Make_Tag_Check --
8198 --------------------
8200 procedure Make_Tag_Check (Targ_Typ : Entity_Id) is
8205 -- [Constraint_Error
8206 -- when Operand /= null
8207 -- and then Operand.all not in Targ_Typ]
8209 if Is_Access_Type (Target_Type) then
8214 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
8215 Right_Opnd => Make_Null (Loc)),
8220 Make_Explicit_Dereference (Loc,
8221 Prefix => Duplicate_Subexpr_No_Checks (Operand)),
8222 Right_Opnd => New_Reference_To (Targ_Typ, Loc)));
8225 -- [Constraint_Error when Operand not in Targ_Typ]
8230 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
8231 Right_Opnd => New_Reference_To (Targ_Typ, Loc));
8235 Make_Raise_Constraint_Error (Loc,
8237 Reason => CE_Tag_Check_Failed));
8240 -- Start of processing
8243 if Is_Access_Type (Target_Type) then
8245 -- Handle entities from the limited view
8248 Available_View (Designated_Type (Operand_Type));
8250 Available_View (Designated_Type (Target_Type));
8252 Actual_Op_Typ := Operand_Type;
8253 Actual_Targ_Typ := Target_Type;
8256 Root_Op_Typ := Root_Type (Actual_Op_Typ);
8258 -- Ada 2005 (AI-251): Handle interface type conversion
8260 if Is_Interface (Actual_Op_Typ) then
8261 Expand_Interface_Conversion (N, Is_Static => False);
8265 if not Tag_Checks_Suppressed (Actual_Targ_Typ) then
8267 -- Create a runtime tag check for a downward class-wide type
8270 if Is_Class_Wide_Type (Actual_Op_Typ)
8271 and then Actual_Op_Typ /= Actual_Targ_Typ
8272 and then Root_Op_Typ /= Actual_Targ_Typ
8273 and then Is_Ancestor (Root_Op_Typ, Actual_Targ_Typ)
8275 Make_Tag_Check (Class_Wide_Type (Actual_Targ_Typ));
8276 Make_Conversion := True;
8279 -- AI05-0073: If the result subtype of the function is defined
8280 -- by an access_definition designating a specific tagged type
8281 -- T, a check is made that the result value is null or the tag
8282 -- of the object designated by the result value identifies T.
8283 -- Constraint_Error is raised if this check fails.
8285 if Nkind (Parent (N)) = Sinfo.N_Return_Statement then
8288 Func_Typ : Entity_Id;
8291 -- Climb scope stack looking for the enclosing function
8293 Func := Current_Scope;
8294 while Present (Func)
8295 and then Ekind (Func) /= E_Function
8297 Func := Scope (Func);
8300 -- The function's return subtype must be defined using
8301 -- an access definition.
8303 if Nkind (Result_Definition (Parent (Func))) =
8306 Func_Typ := Directly_Designated_Type (Etype (Func));
8308 -- The return subtype denotes a specific tagged type,
8309 -- in other words, a non class-wide type.
8311 if Is_Tagged_Type (Func_Typ)
8312 and then not Is_Class_Wide_Type (Func_Typ)
8314 Make_Tag_Check (Actual_Targ_Typ);
8315 Make_Conversion := True;
8321 -- We have generated a tag check for either a class-wide type
8322 -- conversion or for AI05-0073.
8324 if Make_Conversion then
8329 Make_Unchecked_Type_Conversion (Loc,
8330 Subtype_Mark => New_Occurrence_Of (Target_Type, Loc),
8331 Expression => Relocate_Node (Expression (N)));
8333 Analyze_And_Resolve (N, Target_Type);
8339 -- Case of other access type conversions
8341 elsif Is_Access_Type (Target_Type) then
8342 Apply_Constraint_Check (Operand, Target_Type);
8344 -- Case of conversions from a fixed-point type
8346 -- These conversions require special expansion and processing, found in
8347 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
8348 -- since from a semantic point of view, these are simple integer
8349 -- conversions, which do not need further processing.
8351 elsif Is_Fixed_Point_Type (Operand_Type)
8352 and then not Conversion_OK (N)
8354 -- We should never see universal fixed at this case, since the
8355 -- expansion of the constituent divide or multiply should have
8356 -- eliminated the explicit mention of universal fixed.
8358 pragma Assert (Operand_Type /= Universal_Fixed);
8360 -- Check for special case of the conversion to universal real that
8361 -- occurs as a result of the use of a round attribute. In this case,
8362 -- the real type for the conversion is taken from the target type of
8363 -- the Round attribute and the result must be marked as rounded.
8365 if Target_Type = Universal_Real
8366 and then Nkind (Parent (N)) = N_Attribute_Reference
8367 and then Attribute_Name (Parent (N)) = Name_Round
8369 Set_Rounded_Result (N);
8370 Set_Etype (N, Etype (Parent (N)));
8373 -- Otherwise do correct fixed-conversion, but skip these if the
8374 -- Conversion_OK flag is set, because from a semantic point of
8375 -- view these are simple integer conversions needing no further
8376 -- processing (the backend will simply treat them as integers)
8378 if not Conversion_OK (N) then
8379 if Is_Fixed_Point_Type (Etype (N)) then
8380 Expand_Convert_Fixed_To_Fixed (N);
8383 elsif Is_Integer_Type (Etype (N)) then
8384 Expand_Convert_Fixed_To_Integer (N);
8387 pragma Assert (Is_Floating_Point_Type (Etype (N)));
8388 Expand_Convert_Fixed_To_Float (N);
8393 -- Case of conversions to a fixed-point type
8395 -- These conversions require special expansion and processing, found in
8396 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
8397 -- since from a semantic point of view, these are simple integer
8398 -- conversions, which do not need further processing.
8400 elsif Is_Fixed_Point_Type (Target_Type)
8401 and then not Conversion_OK (N)
8403 if Is_Integer_Type (Operand_Type) then
8404 Expand_Convert_Integer_To_Fixed (N);
8407 pragma Assert (Is_Floating_Point_Type (Operand_Type));
8408 Expand_Convert_Float_To_Fixed (N);
8412 -- Case of float-to-integer conversions
8414 -- We also handle float-to-fixed conversions with Conversion_OK set
8415 -- since semantically the fixed-point target is treated as though it
8416 -- were an integer in such cases.
8418 elsif Is_Floating_Point_Type (Operand_Type)
8420 (Is_Integer_Type (Target_Type)
8422 (Is_Fixed_Point_Type (Target_Type) and then Conversion_OK (N)))
8424 -- One more check here, gcc is still not able to do conversions of
8425 -- this type with proper overflow checking, and so gigi is doing an
8426 -- approximation of what is required by doing floating-point compares
8427 -- with the end-point. But that can lose precision in some cases, and
8428 -- give a wrong result. Converting the operand to Universal_Real is
8429 -- helpful, but still does not catch all cases with 64-bit integers
8430 -- on targets with only 64-bit floats
8432 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
8433 -- Can this code be removed ???
8435 if Do_Range_Check (Operand) then
8437 Make_Type_Conversion (Loc,
8439 New_Occurrence_Of (Universal_Real, Loc),
8441 Relocate_Node (Operand)));
8443 Set_Etype (Operand, Universal_Real);
8444 Enable_Range_Check (Operand);
8445 Set_Do_Range_Check (Expression (Operand), False);
8448 -- Case of array conversions
8450 -- Expansion of array conversions, add required length/range checks but
8451 -- only do this if there is no change of representation. For handling of
8452 -- this case, see Handle_Changed_Representation.
8454 elsif Is_Array_Type (Target_Type) then
8456 if Is_Constrained (Target_Type) then
8457 Apply_Length_Check (Operand, Target_Type);
8459 Apply_Range_Check (Operand, Target_Type);
8462 Handle_Changed_Representation;
8464 -- Case of conversions of discriminated types
8466 -- Add required discriminant checks if target is constrained. Again this
8467 -- change is skipped if we have a change of representation.
8469 elsif Has_Discriminants (Target_Type)
8470 and then Is_Constrained (Target_Type)
8472 Apply_Discriminant_Check (Operand, Target_Type);
8473 Handle_Changed_Representation;
8475 -- Case of all other record conversions. The only processing required
8476 -- is to check for a change of representation requiring the special
8477 -- assignment processing.
8479 elsif Is_Record_Type (Target_Type) then
8481 -- Ada 2005 (AI-216): Program_Error is raised when converting from
8482 -- a derived Unchecked_Union type to an unconstrained type that is
8483 -- not Unchecked_Union if the operand lacks inferable discriminants.
8485 if Is_Derived_Type (Operand_Type)
8486 and then Is_Unchecked_Union (Base_Type (Operand_Type))
8487 and then not Is_Constrained (Target_Type)
8488 and then not Is_Unchecked_Union (Base_Type (Target_Type))
8489 and then not Has_Inferable_Discriminants (Operand)
8491 -- To prevent Gigi from generating illegal code, we generate a
8492 -- Program_Error node, but we give it the target type of the
8496 PE : constant Node_Id := Make_Raise_Program_Error (Loc,
8497 Reason => PE_Unchecked_Union_Restriction);
8500 Set_Etype (PE, Target_Type);
8505 Handle_Changed_Representation;
8508 -- Case of conversions of enumeration types
8510 elsif Is_Enumeration_Type (Target_Type) then
8512 -- Special processing is required if there is a change of
8513 -- representation (from enumeration representation clauses)
8515 if not Same_Representation (Target_Type, Operand_Type) then
8517 -- Convert: x(y) to x'val (ytyp'val (y))
8520 Make_Attribute_Reference (Loc,
8521 Prefix => New_Occurrence_Of (Target_Type, Loc),
8522 Attribute_Name => Name_Val,
8523 Expressions => New_List (
8524 Make_Attribute_Reference (Loc,
8525 Prefix => New_Occurrence_Of (Operand_Type, Loc),
8526 Attribute_Name => Name_Pos,
8527 Expressions => New_List (Operand)))));
8529 Analyze_And_Resolve (N, Target_Type);
8532 -- Case of conversions to floating-point
8534 elsif Is_Floating_Point_Type (Target_Type) then
8538 -- At this stage, either the conversion node has been transformed into
8539 -- some other equivalent expression, or left as a conversion that can
8540 -- be handled by Gigi. The conversions that Gigi can handle are the
8543 -- Conversions with no change of representation or type
8545 -- Numeric conversions involving integer, floating- and fixed-point
8546 -- values. Fixed-point values are allowed only if Conversion_OK is
8547 -- set, i.e. if the fixed-point values are to be treated as integers.
8549 -- No other conversions should be passed to Gigi
8551 -- Check: are these rules stated in sinfo??? if so, why restate here???
8553 -- The only remaining step is to generate a range check if we still have
8554 -- a type conversion at this stage and Do_Range_Check is set. For now we
8555 -- do this only for conversions of discrete types.
8557 if Nkind (N) = N_Type_Conversion
8558 and then Is_Discrete_Type (Etype (N))
8561 Expr : constant Node_Id := Expression (N);
8566 if Do_Range_Check (Expr)
8567 and then Is_Discrete_Type (Etype (Expr))
8569 Set_Do_Range_Check (Expr, False);
8571 -- Before we do a range check, we have to deal with treating a
8572 -- fixed-point operand as an integer. The way we do this is
8573 -- simply to do an unchecked conversion to an appropriate
8574 -- integer type large enough to hold the result.
8576 -- This code is not active yet, because we are only dealing
8577 -- with discrete types so far ???
8579 if Nkind (Expr) in N_Has_Treat_Fixed_As_Integer
8580 and then Treat_Fixed_As_Integer (Expr)
8582 Ftyp := Base_Type (Etype (Expr));
8584 if Esize (Ftyp) >= Esize (Standard_Integer) then
8585 Ityp := Standard_Long_Long_Integer;
8587 Ityp := Standard_Integer;
8590 Rewrite (Expr, Unchecked_Convert_To (Ityp, Expr));
8593 -- Reset overflow flag, since the range check will include
8594 -- dealing with possible overflow, and generate the check If
8595 -- Address is either a source type or target type, suppress
8596 -- range check to avoid typing anomalies when it is a visible
8599 Set_Do_Overflow_Check (N, False);
8600 if not Is_Descendent_Of_Address (Etype (Expr))
8601 and then not Is_Descendent_Of_Address (Target_Type)
8603 Generate_Range_Check
8604 (Expr, Target_Type, CE_Range_Check_Failed);
8610 -- Final step, if the result is a type conversion involving Vax_Float
8611 -- types, then it is subject for further special processing.
8613 if Nkind (N) = N_Type_Conversion
8614 and then (Vax_Float (Operand_Type) or else Vax_Float (Target_Type))
8616 Expand_Vax_Conversion (N);
8619 end Expand_N_Type_Conversion;
8621 -----------------------------------
8622 -- Expand_N_Unchecked_Expression --
8623 -----------------------------------
8625 -- Remove the unchecked expression node from the tree. It's job was simply
8626 -- to make sure that its constituent expression was handled with checks
8627 -- off, and now that that is done, we can remove it from the tree, and
8628 -- indeed must, since gigi does not expect to see these nodes.
8630 procedure Expand_N_Unchecked_Expression (N : Node_Id) is
8631 Exp : constant Node_Id := Expression (N);
8634 Set_Assignment_OK (Exp, Assignment_OK (N) or Assignment_OK (Exp));
8636 end Expand_N_Unchecked_Expression;
8638 ----------------------------------------
8639 -- Expand_N_Unchecked_Type_Conversion --
8640 ----------------------------------------
8642 -- If this cannot be handled by Gigi and we haven't already made a
8643 -- temporary for it, do it now.
8645 procedure Expand_N_Unchecked_Type_Conversion (N : Node_Id) is
8646 Target_Type : constant Entity_Id := Etype (N);
8647 Operand : constant Node_Id := Expression (N);
8648 Operand_Type : constant Entity_Id := Etype (Operand);
8651 -- Nothing at all to do if conversion is to the identical type so remove
8652 -- the conversion completely, it is useless, except that it may carry
8653 -- an Assignment_OK indication which must be proprgated to the operand.
8655 if Operand_Type = Target_Type then
8656 if Assignment_OK (N) then
8657 Set_Assignment_OK (Operand);
8660 Rewrite (N, Relocate_Node (Operand));
8664 -- If we have a conversion of a compile time known value to a target
8665 -- type and the value is in range of the target type, then we can simply
8666 -- replace the construct by an integer literal of the correct type. We
8667 -- only apply this to integer types being converted. Possibly it may
8668 -- apply in other cases, but it is too much trouble to worry about.
8670 -- Note that we do not do this transformation if the Kill_Range_Check
8671 -- flag is set, since then the value may be outside the expected range.
8672 -- This happens in the Normalize_Scalars case.
8674 -- We also skip this if either the target or operand type is biased
8675 -- because in this case, the unchecked conversion is supposed to
8676 -- preserve the bit pattern, not the integer value.
8678 if Is_Integer_Type (Target_Type)
8679 and then not Has_Biased_Representation (Target_Type)
8680 and then Is_Integer_Type (Operand_Type)
8681 and then not Has_Biased_Representation (Operand_Type)
8682 and then Compile_Time_Known_Value (Operand)
8683 and then not Kill_Range_Check (N)
8686 Val : constant Uint := Expr_Value (Operand);
8689 if Compile_Time_Known_Value (Type_Low_Bound (Target_Type))
8691 Compile_Time_Known_Value (Type_High_Bound (Target_Type))
8693 Val >= Expr_Value (Type_Low_Bound (Target_Type))
8695 Val <= Expr_Value (Type_High_Bound (Target_Type))
8697 Rewrite (N, Make_Integer_Literal (Sloc (N), Val));
8699 -- If Address is the target type, just set the type to avoid a
8700 -- spurious type error on the literal when Address is a visible
8703 if Is_Descendent_Of_Address (Target_Type) then
8704 Set_Etype (N, Target_Type);
8706 Analyze_And_Resolve (N, Target_Type);
8714 -- Nothing to do if conversion is safe
8716 if Safe_Unchecked_Type_Conversion (N) then
8720 -- Otherwise force evaluation unless Assignment_OK flag is set (this
8721 -- flag indicates ??? -- more comments needed here)
8723 if Assignment_OK (N) then
8726 Force_Evaluation (N);
8728 end Expand_N_Unchecked_Type_Conversion;
8730 ----------------------------
8731 -- Expand_Record_Equality --
8732 ----------------------------
8734 -- For non-variant records, Equality is expanded when needed into:
8736 -- and then Lhs.Discr1 = Rhs.Discr1
8738 -- and then Lhs.Discrn = Rhs.Discrn
8739 -- and then Lhs.Cmp1 = Rhs.Cmp1
8741 -- and then Lhs.Cmpn = Rhs.Cmpn
8743 -- The expression is folded by the back-end for adjacent fields. This
8744 -- function is called for tagged record in only one occasion: for imple-
8745 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
8746 -- otherwise the primitive "=" is used directly.
8748 function Expand_Record_Equality
8753 Bodies : List_Id) return Node_Id
8755 Loc : constant Source_Ptr := Sloc (Nod);
8760 First_Time : Boolean := True;
8762 function Suitable_Element (C : Entity_Id) return Entity_Id;
8763 -- Return the first field to compare beginning with C, skipping the
8764 -- inherited components.
8766 ----------------------
8767 -- Suitable_Element --
8768 ----------------------
8770 function Suitable_Element (C : Entity_Id) return Entity_Id is
8775 elsif Ekind (C) /= E_Discriminant
8776 and then Ekind (C) /= E_Component
8778 return Suitable_Element (Next_Entity (C));
8780 elsif Is_Tagged_Type (Typ)
8781 and then C /= Original_Record_Component (C)
8783 return Suitable_Element (Next_Entity (C));
8785 elsif Chars (C) = Name_uController
8786 or else Chars (C) = Name_uTag
8788 return Suitable_Element (Next_Entity (C));
8790 elsif Is_Interface (Etype (C)) then
8791 return Suitable_Element (Next_Entity (C));
8796 end Suitable_Element;
8798 -- Start of processing for Expand_Record_Equality
8801 -- Generates the following code: (assuming that Typ has one Discr and
8802 -- component C2 is also a record)
8805 -- and then Lhs.Discr1 = Rhs.Discr1
8806 -- and then Lhs.C1 = Rhs.C1
8807 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
8809 -- and then Lhs.Cmpn = Rhs.Cmpn
8811 Result := New_Reference_To (Standard_True, Loc);
8812 C := Suitable_Element (First_Entity (Typ));
8814 while Present (C) loop
8822 First_Time := False;
8826 New_Lhs := New_Copy_Tree (Lhs);
8827 New_Rhs := New_Copy_Tree (Rhs);
8831 Expand_Composite_Equality (Nod, Etype (C),
8833 Make_Selected_Component (Loc,
8835 Selector_Name => New_Reference_To (C, Loc)),
8837 Make_Selected_Component (Loc,
8839 Selector_Name => New_Reference_To (C, Loc)),
8842 -- If some (sub)component is an unchecked_union, the whole
8843 -- operation will raise program error.
8845 if Nkind (Check) = N_Raise_Program_Error then
8847 Set_Etype (Result, Standard_Boolean);
8852 Left_Opnd => Result,
8853 Right_Opnd => Check);
8857 C := Suitable_Element (Next_Entity (C));
8861 end Expand_Record_Equality;
8863 -------------------------------------
8864 -- Fixup_Universal_Fixed_Operation --
8865 -------------------------------------
8867 procedure Fixup_Universal_Fixed_Operation (N : Node_Id) is
8868 Conv : constant Node_Id := Parent (N);
8871 -- We must have a type conversion immediately above us
8873 pragma Assert (Nkind (Conv) = N_Type_Conversion);
8875 -- Normally the type conversion gives our target type. The exception
8876 -- occurs in the case of the Round attribute, where the conversion
8877 -- will be to universal real, and our real type comes from the Round
8878 -- attribute (as well as an indication that we must round the result)
8880 if Nkind (Parent (Conv)) = N_Attribute_Reference
8881 and then Attribute_Name (Parent (Conv)) = Name_Round
8883 Set_Etype (N, Etype (Parent (Conv)));
8884 Set_Rounded_Result (N);
8886 -- Normal case where type comes from conversion above us
8889 Set_Etype (N, Etype (Conv));
8891 end Fixup_Universal_Fixed_Operation;
8893 ------------------------------
8894 -- Get_Allocator_Final_List --
8895 ------------------------------
8897 function Get_Allocator_Final_List
8900 PtrT : Entity_Id) return Entity_Id
8902 Loc : constant Source_Ptr := Sloc (N);
8904 Owner : Entity_Id := PtrT;
8905 -- The entity whose finalization list must be used to attach the
8906 -- allocated object.
8909 if Ekind (PtrT) = E_Anonymous_Access_Type then
8911 -- If the context is an access parameter, we need to create a
8912 -- non-anonymous access type in order to have a usable final list,
8913 -- because there is otherwise no pool to which the allocated object
8914 -- can belong. We create both the type and the finalization chain
8915 -- here, because freezing an internal type does not create such a
8916 -- chain. The Final_Chain that is thus created is shared by the
8917 -- access parameter. The access type is tested against the result
8918 -- type of the function to exclude allocators whose type is an
8919 -- anonymous access result type. We freeze the type at once to
8920 -- ensure that it is properly decorated for the back-end, even
8921 -- if the context and current scope is a loop.
8923 if Nkind (Associated_Node_For_Itype (PtrT))
8924 in N_Subprogram_Specification
8927 Etype (Defining_Unit_Name (Associated_Node_For_Itype (PtrT)))
8929 Owner := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
8931 Make_Full_Type_Declaration (Loc,
8932 Defining_Identifier => Owner,
8934 Make_Access_To_Object_Definition (Loc,
8935 Subtype_Indication =>
8936 New_Occurrence_Of (T, Loc))));
8938 Freeze_Before (N, Owner);
8939 Build_Final_List (N, Owner);
8940 Set_Associated_Final_Chain (PtrT, Associated_Final_Chain (Owner));
8942 -- Ada 2005 (AI-318-02): If the context is a return object
8943 -- declaration, then the anonymous return subtype is defined to have
8944 -- the same accessibility level as that of the function's result
8945 -- subtype, which means that we want the scope where the function is
8948 elsif Nkind (Associated_Node_For_Itype (PtrT)) = N_Object_Declaration
8949 and then Ekind (Scope (PtrT)) = E_Return_Statement
8951 Owner := Scope (Return_Applies_To (Scope (PtrT)));
8953 -- Case of an access discriminant, or (Ada 2005), of an anonymous
8954 -- access component or anonymous access function result: find the
8955 -- final list associated with the scope of the type. (In the
8956 -- anonymous access component kind, a list controller will have
8957 -- been allocated when freezing the record type, and PtrT has an
8958 -- Associated_Final_Chain attribute designating it.)
8960 elsif No (Associated_Final_Chain (PtrT)) then
8961 Owner := Scope (PtrT);
8965 return Find_Final_List (Owner);
8966 end Get_Allocator_Final_List;
8968 ---------------------------------
8969 -- Has_Inferable_Discriminants --
8970 ---------------------------------
8972 function Has_Inferable_Discriminants (N : Node_Id) return Boolean is
8974 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean;
8975 -- Determines whether the left-most prefix of a selected component is a
8976 -- formal parameter in a subprogram. Assumes N is a selected component.
8978 --------------------------------
8979 -- Prefix_Is_Formal_Parameter --
8980 --------------------------------
8982 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean is
8983 Sel_Comp : Node_Id := N;
8986 -- Move to the left-most prefix by climbing up the tree
8988 while Present (Parent (Sel_Comp))
8989 and then Nkind (Parent (Sel_Comp)) = N_Selected_Component
8991 Sel_Comp := Parent (Sel_Comp);
8994 return Ekind (Entity (Prefix (Sel_Comp))) in Formal_Kind;
8995 end Prefix_Is_Formal_Parameter;
8997 -- Start of processing for Has_Inferable_Discriminants
9000 -- For identifiers and indexed components, it is sufficient to have a
9001 -- constrained Unchecked_Union nominal subtype.
9003 if Nkind_In (N, N_Identifier, N_Indexed_Component) then
9004 return Is_Unchecked_Union (Base_Type (Etype (N)))
9006 Is_Constrained (Etype (N));
9008 -- For selected components, the subtype of the selector must be a
9009 -- constrained Unchecked_Union. If the component is subject to a
9010 -- per-object constraint, then the enclosing object must have inferable
9013 elsif Nkind (N) = N_Selected_Component then
9014 if Has_Per_Object_Constraint (Entity (Selector_Name (N))) then
9016 -- A small hack. If we have a per-object constrained selected
9017 -- component of a formal parameter, return True since we do not
9018 -- know the actual parameter association yet.
9020 if Prefix_Is_Formal_Parameter (N) then
9024 -- Otherwise, check the enclosing object and the selector
9026 return Has_Inferable_Discriminants (Prefix (N))
9028 Has_Inferable_Discriminants (Selector_Name (N));
9031 -- The call to Has_Inferable_Discriminants will determine whether
9032 -- the selector has a constrained Unchecked_Union nominal type.
9034 return Has_Inferable_Discriminants (Selector_Name (N));
9036 -- A qualified expression has inferable discriminants if its subtype
9037 -- mark is a constrained Unchecked_Union subtype.
9039 elsif Nkind (N) = N_Qualified_Expression then
9040 return Is_Unchecked_Union (Subtype_Mark (N))
9042 Is_Constrained (Subtype_Mark (N));
9047 end Has_Inferable_Discriminants;
9049 -------------------------------
9050 -- Insert_Dereference_Action --
9051 -------------------------------
9053 procedure Insert_Dereference_Action (N : Node_Id) is
9054 Loc : constant Source_Ptr := Sloc (N);
9055 Typ : constant Entity_Id := Etype (N);
9056 Pool : constant Entity_Id := Associated_Storage_Pool (Typ);
9057 Pnod : constant Node_Id := Parent (N);
9059 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean;
9060 -- Return true if type of P is derived from Checked_Pool;
9062 -----------------------------
9063 -- Is_Checked_Storage_Pool --
9064 -----------------------------
9066 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean is
9075 while T /= Etype (T) loop
9076 if Is_RTE (T, RE_Checked_Pool) then
9084 end Is_Checked_Storage_Pool;
9086 -- Start of processing for Insert_Dereference_Action
9089 pragma Assert (Nkind (Pnod) = N_Explicit_Dereference);
9091 if not (Is_Checked_Storage_Pool (Pool)
9092 and then Comes_From_Source (Original_Node (Pnod)))
9098 Make_Procedure_Call_Statement (Loc,
9099 Name => New_Reference_To (
9100 Find_Prim_Op (Etype (Pool), Name_Dereference), Loc),
9102 Parameter_Associations => New_List (
9106 New_Reference_To (Pool, Loc),
9108 -- Storage_Address. We use the attribute Pool_Address, which uses
9109 -- the pointer itself to find the address of the object, and which
9110 -- handles unconstrained arrays properly by computing the address
9111 -- of the template. i.e. the correct address of the corresponding
9114 Make_Attribute_Reference (Loc,
9115 Prefix => Duplicate_Subexpr_Move_Checks (N),
9116 Attribute_Name => Name_Pool_Address),
9118 -- Size_In_Storage_Elements
9120 Make_Op_Divide (Loc,
9122 Make_Attribute_Reference (Loc,
9124 Make_Explicit_Dereference (Loc,
9125 Duplicate_Subexpr_Move_Checks (N)),
9126 Attribute_Name => Name_Size),
9128 Make_Integer_Literal (Loc, System_Storage_Unit)),
9132 Make_Attribute_Reference (Loc,
9134 Make_Explicit_Dereference (Loc,
9135 Duplicate_Subexpr_Move_Checks (N)),
9136 Attribute_Name => Name_Alignment))));
9139 when RE_Not_Available =>
9141 end Insert_Dereference_Action;
9143 --------------------------------
9144 -- Integer_Promotion_Possible --
9145 --------------------------------
9147 function Integer_Promotion_Possible (N : Node_Id) return Boolean is
9148 Operand : constant Node_Id := Expression (N);
9149 Operand_Type : constant Entity_Id := Etype (Operand);
9150 Root_Operand_Type : constant Entity_Id := Root_Type (Operand_Type);
9153 pragma Assert (Nkind (N) = N_Type_Conversion);
9157 -- We only do the transformation for source constructs. We assume
9158 -- that the expander knows what it is doing when it generates code.
9160 Comes_From_Source (N)
9162 -- If the operand type is Short_Integer or Short_Short_Integer,
9163 -- then we will promote to Integer, which is available on all
9164 -- targets, and is sufficient to ensure no intermediate overflow.
9165 -- Furthermore it is likely to be as efficient or more efficient
9166 -- than using the smaller type for the computation so we do this
9170 (Root_Operand_Type = Base_Type (Standard_Short_Integer)
9172 Root_Operand_Type = Base_Type (Standard_Short_Short_Integer))
9174 -- Test for interesting operation, which includes addition,
9175 -- division, exponentiation, multiplication, subtraction, absolute
9176 -- value and unary negation. Unary "+" is omitted since it is a
9177 -- no-op and thus can't overflow.
9179 and then Nkind_In (Operand, N_Op_Abs,
9186 end Integer_Promotion_Possible;
9188 ------------------------------
9189 -- Make_Array_Comparison_Op --
9190 ------------------------------
9192 -- This is a hand-coded expansion of the following generic function:
9195 -- type elem is (<>);
9196 -- type index is (<>);
9197 -- type a is array (index range <>) of elem;
9199 -- function Gnnn (X : a; Y: a) return boolean is
9200 -- J : index := Y'first;
9203 -- if X'length = 0 then
9206 -- elsif Y'length = 0 then
9210 -- for I in X'range loop
9211 -- if X (I) = Y (J) then
9212 -- if J = Y'last then
9215 -- J := index'succ (J);
9219 -- return X (I) > Y (J);
9223 -- return X'length > Y'length;
9227 -- Note that since we are essentially doing this expansion by hand, we
9228 -- do not need to generate an actual or formal generic part, just the
9229 -- instantiated function itself.
9231 function Make_Array_Comparison_Op
9233 Nod : Node_Id) return Node_Id
9235 Loc : constant Source_Ptr := Sloc (Nod);
9237 X : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uX);
9238 Y : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uY);
9239 I : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uI);
9240 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
9242 Index : constant Entity_Id := Base_Type (Etype (First_Index (Typ)));
9244 Loop_Statement : Node_Id;
9245 Loop_Body : Node_Id;
9248 Final_Expr : Node_Id;
9249 Func_Body : Node_Id;
9250 Func_Name : Entity_Id;
9256 -- if J = Y'last then
9259 -- J := index'succ (J);
9263 Make_Implicit_If_Statement (Nod,
9266 Left_Opnd => New_Reference_To (J, Loc),
9268 Make_Attribute_Reference (Loc,
9269 Prefix => New_Reference_To (Y, Loc),
9270 Attribute_Name => Name_Last)),
9272 Then_Statements => New_List (
9273 Make_Exit_Statement (Loc)),
9277 Make_Assignment_Statement (Loc,
9278 Name => New_Reference_To (J, Loc),
9280 Make_Attribute_Reference (Loc,
9281 Prefix => New_Reference_To (Index, Loc),
9282 Attribute_Name => Name_Succ,
9283 Expressions => New_List (New_Reference_To (J, Loc))))));
9285 -- if X (I) = Y (J) then
9288 -- return X (I) > Y (J);
9292 Make_Implicit_If_Statement (Nod,
9296 Make_Indexed_Component (Loc,
9297 Prefix => New_Reference_To (X, Loc),
9298 Expressions => New_List (New_Reference_To (I, Loc))),
9301 Make_Indexed_Component (Loc,
9302 Prefix => New_Reference_To (Y, Loc),
9303 Expressions => New_List (New_Reference_To (J, Loc)))),
9305 Then_Statements => New_List (Inner_If),
9307 Else_Statements => New_List (
9308 Make_Simple_Return_Statement (Loc,
9312 Make_Indexed_Component (Loc,
9313 Prefix => New_Reference_To (X, Loc),
9314 Expressions => New_List (New_Reference_To (I, Loc))),
9317 Make_Indexed_Component (Loc,
9318 Prefix => New_Reference_To (Y, Loc),
9319 Expressions => New_List (
9320 New_Reference_To (J, Loc)))))));
9322 -- for I in X'range loop
9327 Make_Implicit_Loop_Statement (Nod,
9328 Identifier => Empty,
9331 Make_Iteration_Scheme (Loc,
9332 Loop_Parameter_Specification =>
9333 Make_Loop_Parameter_Specification (Loc,
9334 Defining_Identifier => I,
9335 Discrete_Subtype_Definition =>
9336 Make_Attribute_Reference (Loc,
9337 Prefix => New_Reference_To (X, Loc),
9338 Attribute_Name => Name_Range))),
9340 Statements => New_List (Loop_Body));
9342 -- if X'length = 0 then
9344 -- elsif Y'length = 0 then
9347 -- for ... loop ... end loop;
9348 -- return X'length > Y'length;
9352 Make_Attribute_Reference (Loc,
9353 Prefix => New_Reference_To (X, Loc),
9354 Attribute_Name => Name_Length);
9357 Make_Attribute_Reference (Loc,
9358 Prefix => New_Reference_To (Y, Loc),
9359 Attribute_Name => Name_Length);
9363 Left_Opnd => Length1,
9364 Right_Opnd => Length2);
9367 Make_Implicit_If_Statement (Nod,
9371 Make_Attribute_Reference (Loc,
9372 Prefix => New_Reference_To (X, Loc),
9373 Attribute_Name => Name_Length),
9375 Make_Integer_Literal (Loc, 0)),
9379 Make_Simple_Return_Statement (Loc,
9380 Expression => New_Reference_To (Standard_False, Loc))),
9382 Elsif_Parts => New_List (
9383 Make_Elsif_Part (Loc,
9387 Make_Attribute_Reference (Loc,
9388 Prefix => New_Reference_To (Y, Loc),
9389 Attribute_Name => Name_Length),
9391 Make_Integer_Literal (Loc, 0)),
9395 Make_Simple_Return_Statement (Loc,
9396 Expression => New_Reference_To (Standard_True, Loc))))),
9398 Else_Statements => New_List (
9400 Make_Simple_Return_Statement (Loc,
9401 Expression => Final_Expr)));
9405 Formals := New_List (
9406 Make_Parameter_Specification (Loc,
9407 Defining_Identifier => X,
9408 Parameter_Type => New_Reference_To (Typ, Loc)),
9410 Make_Parameter_Specification (Loc,
9411 Defining_Identifier => Y,
9412 Parameter_Type => New_Reference_To (Typ, Loc)));
9414 -- function Gnnn (...) return boolean is
9415 -- J : index := Y'first;
9420 Func_Name := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
9423 Make_Subprogram_Body (Loc,
9425 Make_Function_Specification (Loc,
9426 Defining_Unit_Name => Func_Name,
9427 Parameter_Specifications => Formals,
9428 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
9430 Declarations => New_List (
9431 Make_Object_Declaration (Loc,
9432 Defining_Identifier => J,
9433 Object_Definition => New_Reference_To (Index, Loc),
9435 Make_Attribute_Reference (Loc,
9436 Prefix => New_Reference_To (Y, Loc),
9437 Attribute_Name => Name_First))),
9439 Handled_Statement_Sequence =>
9440 Make_Handled_Sequence_Of_Statements (Loc,
9441 Statements => New_List (If_Stat)));
9444 end Make_Array_Comparison_Op;
9446 ---------------------------
9447 -- Make_Boolean_Array_Op --
9448 ---------------------------
9450 -- For logical operations on boolean arrays, expand in line the following,
9451 -- replacing 'and' with 'or' or 'xor' where needed:
9453 -- function Annn (A : typ; B: typ) return typ is
9456 -- for J in A'range loop
9457 -- C (J) := A (J) op B (J);
9462 -- Here typ is the boolean array type
9464 function Make_Boolean_Array_Op
9466 N : Node_Id) return Node_Id
9468 Loc : constant Source_Ptr := Sloc (N);
9470 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
9471 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
9472 C : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uC);
9473 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
9481 Func_Name : Entity_Id;
9482 Func_Body : Node_Id;
9483 Loop_Statement : Node_Id;
9487 Make_Indexed_Component (Loc,
9488 Prefix => New_Reference_To (A, Loc),
9489 Expressions => New_List (New_Reference_To (J, Loc)));
9492 Make_Indexed_Component (Loc,
9493 Prefix => New_Reference_To (B, Loc),
9494 Expressions => New_List (New_Reference_To (J, Loc)));
9497 Make_Indexed_Component (Loc,
9498 Prefix => New_Reference_To (C, Loc),
9499 Expressions => New_List (New_Reference_To (J, Loc)));
9501 if Nkind (N) = N_Op_And then
9507 elsif Nkind (N) = N_Op_Or then
9521 Make_Implicit_Loop_Statement (N,
9522 Identifier => Empty,
9525 Make_Iteration_Scheme (Loc,
9526 Loop_Parameter_Specification =>
9527 Make_Loop_Parameter_Specification (Loc,
9528 Defining_Identifier => J,
9529 Discrete_Subtype_Definition =>
9530 Make_Attribute_Reference (Loc,
9531 Prefix => New_Reference_To (A, Loc),
9532 Attribute_Name => Name_Range))),
9534 Statements => New_List (
9535 Make_Assignment_Statement (Loc,
9537 Expression => Op)));
9539 Formals := New_List (
9540 Make_Parameter_Specification (Loc,
9541 Defining_Identifier => A,
9542 Parameter_Type => New_Reference_To (Typ, Loc)),
9544 Make_Parameter_Specification (Loc,
9545 Defining_Identifier => B,
9546 Parameter_Type => New_Reference_To (Typ, Loc)));
9549 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
9550 Set_Is_Inlined (Func_Name);
9553 Make_Subprogram_Body (Loc,
9555 Make_Function_Specification (Loc,
9556 Defining_Unit_Name => Func_Name,
9557 Parameter_Specifications => Formals,
9558 Result_Definition => New_Reference_To (Typ, Loc)),
9560 Declarations => New_List (
9561 Make_Object_Declaration (Loc,
9562 Defining_Identifier => C,
9563 Object_Definition => New_Reference_To (Typ, Loc))),
9565 Handled_Statement_Sequence =>
9566 Make_Handled_Sequence_Of_Statements (Loc,
9567 Statements => New_List (
9569 Make_Simple_Return_Statement (Loc,
9570 Expression => New_Reference_To (C, Loc)))));
9573 end Make_Boolean_Array_Op;
9575 ------------------------
9576 -- Rewrite_Comparison --
9577 ------------------------
9579 procedure Rewrite_Comparison (N : Node_Id) is
9580 Warning_Generated : Boolean := False;
9581 -- Set to True if first pass with Assume_Valid generates a warning in
9582 -- which case we skip the second pass to avoid warning overloaded.
9585 -- Set to Standard_True or Standard_False
9588 if Nkind (N) = N_Type_Conversion then
9589 Rewrite_Comparison (Expression (N));
9592 elsif Nkind (N) not in N_Op_Compare then
9596 -- Now start looking at the comparison in detail. We potentially go
9597 -- through this loop twice. The first time, Assume_Valid is set False
9598 -- in the call to Compile_Time_Compare. If this call results in a
9599 -- clear result of always True or Always False, that's decisive and
9600 -- we are done. Otherwise we repeat the processing with Assume_Valid
9601 -- set to True to generate additional warnings. We can stil that step
9602 -- if Constant_Condition_Warnings is False.
9604 for AV in False .. True loop
9606 Typ : constant Entity_Id := Etype (N);
9607 Op1 : constant Node_Id := Left_Opnd (N);
9608 Op2 : constant Node_Id := Right_Opnd (N);
9610 Res : constant Compare_Result :=
9611 Compile_Time_Compare (Op1, Op2, Assume_Valid => AV);
9612 -- Res indicates if compare outcome can be compile time determined
9614 True_Result : Boolean;
9615 False_Result : Boolean;
9618 case N_Op_Compare (Nkind (N)) is
9620 True_Result := Res = EQ;
9621 False_Result := Res = LT or else Res = GT or else Res = NE;
9624 True_Result := Res in Compare_GE;
9625 False_Result := Res = LT;
9628 and then Constant_Condition_Warnings
9629 and then Comes_From_Source (Original_Node (N))
9630 and then Nkind (Original_Node (N)) = N_Op_Ge
9631 and then not In_Instance
9632 and then Is_Integer_Type (Etype (Left_Opnd (N)))
9633 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
9636 ("can never be greater than, could replace by ""'=""?", N);
9637 Warning_Generated := True;
9641 True_Result := Res = GT;
9642 False_Result := Res in Compare_LE;
9645 True_Result := Res = LT;
9646 False_Result := Res in Compare_GE;
9649 True_Result := Res in Compare_LE;
9650 False_Result := Res = GT;
9653 and then Constant_Condition_Warnings
9654 and then Comes_From_Source (Original_Node (N))
9655 and then Nkind (Original_Node (N)) = N_Op_Le
9656 and then not In_Instance
9657 and then Is_Integer_Type (Etype (Left_Opnd (N)))
9658 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
9661 ("can never be less than, could replace by ""'=""?", N);
9662 Warning_Generated := True;
9666 True_Result := Res = NE or else Res = GT or else Res = LT;
9667 False_Result := Res = EQ;
9670 -- If this is the first iteration, then we actually convert the
9671 -- comparison into True or False, if the result is certain.
9674 if True_Result or False_Result then
9676 Result := Standard_True;
9678 Result := Standard_False;
9683 New_Occurrence_Of (Result, Sloc (N))));
9684 Analyze_And_Resolve (N, Typ);
9685 Warn_On_Known_Condition (N);
9689 -- If this is the second iteration (AV = True), and the original
9690 -- node comes from source and we are not in an instance, then
9691 -- give a warning if we know result would be True or False. Note
9692 -- we know Constant_Condition_Warnings is set if we get here.
9694 elsif Comes_From_Source (Original_Node (N))
9695 and then not In_Instance
9699 ("condition can only be False if invalid values present?",
9701 elsif False_Result then
9703 ("condition can only be True if invalid values present?",
9709 -- Skip second iteration if not warning on constant conditions or
9710 -- if the first iteration already generated a warning of some kind
9711 -- or if we are in any case assuming all values are valid (so that
9712 -- the first iteration took care of the valid case).
9714 exit when not Constant_Condition_Warnings;
9715 exit when Warning_Generated;
9716 exit when Assume_No_Invalid_Values;
9718 end Rewrite_Comparison;
9720 ----------------------------
9721 -- Safe_In_Place_Array_Op --
9722 ----------------------------
9724 function Safe_In_Place_Array_Op
9727 Op2 : Node_Id) return Boolean
9731 function Is_Safe_Operand (Op : Node_Id) return Boolean;
9732 -- Operand is safe if it cannot overlap part of the target of the
9733 -- operation. If the operand and the target are identical, the operand
9734 -- is safe. The operand can be empty in the case of negation.
9736 function Is_Unaliased (N : Node_Id) return Boolean;
9737 -- Check that N is a stand-alone entity
9743 function Is_Unaliased (N : Node_Id) return Boolean is
9747 and then No (Address_Clause (Entity (N)))
9748 and then No (Renamed_Object (Entity (N)));
9751 ---------------------
9752 -- Is_Safe_Operand --
9753 ---------------------
9755 function Is_Safe_Operand (Op : Node_Id) return Boolean is
9760 elsif Is_Entity_Name (Op) then
9761 return Is_Unaliased (Op);
9763 elsif Nkind_In (Op, N_Indexed_Component, N_Selected_Component) then
9764 return Is_Unaliased (Prefix (Op));
9766 elsif Nkind (Op) = N_Slice then
9768 Is_Unaliased (Prefix (Op))
9769 and then Entity (Prefix (Op)) /= Target;
9771 elsif Nkind (Op) = N_Op_Not then
9772 return Is_Safe_Operand (Right_Opnd (Op));
9777 end Is_Safe_Operand;
9779 -- Start of processing for Is_Safe_In_Place_Array_Op
9782 -- Skip this processing if the component size is different from system
9783 -- storage unit (since at least for NOT this would cause problems).
9785 if Component_Size (Etype (Lhs)) /= System_Storage_Unit then
9788 -- Cannot do in place stuff on VM_Target since cannot pass addresses
9790 elsif VM_Target /= No_VM then
9793 -- Cannot do in place stuff if non-standard Boolean representation
9795 elsif Has_Non_Standard_Rep (Component_Type (Etype (Lhs))) then
9798 elsif not Is_Unaliased (Lhs) then
9801 Target := Entity (Lhs);
9804 Is_Safe_Operand (Op1)
9805 and then Is_Safe_Operand (Op2);
9807 end Safe_In_Place_Array_Op;
9809 -----------------------
9810 -- Tagged_Membership --
9811 -----------------------
9813 -- There are two different cases to consider depending on whether the right
9814 -- operand is a class-wide type or not. If not we just compare the actual
9815 -- tag of the left expr to the target type tag:
9817 -- Left_Expr.Tag = Right_Type'Tag;
9819 -- If it is a class-wide type we use the RT function CW_Membership which is
9820 -- usually implemented by looking in the ancestor tables contained in the
9821 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
9823 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
9824 -- function IW_Membership which is usually implemented by looking in the
9825 -- table of abstract interface types plus the ancestor table contained in
9826 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
9828 function Tagged_Membership (N : Node_Id) return Node_Id is
9829 Left : constant Node_Id := Left_Opnd (N);
9830 Right : constant Node_Id := Right_Opnd (N);
9831 Loc : constant Source_Ptr := Sloc (N);
9833 Left_Type : Entity_Id;
9834 Right_Type : Entity_Id;
9838 -- Handle entities from the limited view
9840 Left_Type := Available_View (Etype (Left));
9841 Right_Type := Available_View (Etype (Right));
9843 if Is_Class_Wide_Type (Left_Type) then
9844 Left_Type := Root_Type (Left_Type);
9848 Make_Selected_Component (Loc,
9849 Prefix => Relocate_Node (Left),
9851 New_Reference_To (First_Tag_Component (Left_Type), Loc));
9853 if Is_Class_Wide_Type (Right_Type) then
9855 -- No need to issue a run-time check if we statically know that the
9856 -- result of this membership test is always true. For example,
9857 -- considering the following declarations:
9859 -- type Iface is interface;
9860 -- type T is tagged null record;
9861 -- type DT is new T and Iface with null record;
9866 -- These membership tests are always true:
9870 -- Obj2 in Iface'Class;
9872 -- We do not need to handle cases where the membership is illegal.
9875 -- Obj1 in DT'Class; -- Compile time error
9876 -- Obj1 in Iface'Class; -- Compile time error
9878 if not Is_Class_Wide_Type (Left_Type)
9879 and then (Is_Ancestor (Etype (Right_Type), Left_Type)
9880 or else (Is_Interface (Etype (Right_Type))
9881 and then Interface_Present_In_Ancestor
9883 Iface => Etype (Right_Type))))
9885 return New_Reference_To (Standard_True, Loc);
9888 -- Ada 2005 (AI-251): Class-wide applied to interfaces
9890 if Is_Interface (Etype (Class_Wide_Type (Right_Type)))
9892 -- Support to: "Iface_CW_Typ in Typ'Class"
9894 or else Is_Interface (Left_Type)
9896 -- Issue error if IW_Membership operation not available in a
9897 -- configurable run time setting.
9899 if not RTE_Available (RE_IW_Membership) then
9901 ("dynamic membership test on interface types", N);
9906 Make_Function_Call (Loc,
9907 Name => New_Occurrence_Of (RTE (RE_IW_Membership), Loc),
9908 Parameter_Associations => New_List (
9909 Make_Attribute_Reference (Loc,
9911 Attribute_Name => Name_Address),
9914 (Access_Disp_Table (Root_Type (Right_Type)))),
9917 -- Ada 95: Normal case
9921 Build_CW_Membership (Loc,
9922 Obj_Tag_Node => Obj_Tag,
9926 (Access_Disp_Table (Root_Type (Right_Type)))),
9930 -- Right_Type is not a class-wide type
9933 -- No need to check the tag of the object if Right_Typ is abstract
9935 if Is_Abstract_Type (Right_Type) then
9936 return New_Reference_To (Standard_False, Loc);
9941 Left_Opnd => Obj_Tag,
9944 (Node (First_Elmt (Access_Disp_Table (Right_Type))), Loc));
9947 end Tagged_Membership;
9949 ------------------------------
9950 -- Unary_Op_Validity_Checks --
9951 ------------------------------
9953 procedure Unary_Op_Validity_Checks (N : Node_Id) is
9955 if Validity_Checks_On and Validity_Check_Operands then
9956 Ensure_Valid (Right_Opnd (N));
9958 end Unary_Op_Validity_Checks;
OSDN Git Service
