1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Aggr; use Exp_Aggr;
33 with Exp_Atag; use Exp_Atag;
34 with Exp_Ch2; use Exp_Ch2;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch6; use Exp_Ch6;
37 with Exp_Ch7; use Exp_Ch7;
38 with Exp_Ch9; use Exp_Ch9;
39 with Exp_Disp; use Exp_Disp;
40 with Exp_Fixd; use Exp_Fixd;
41 with Exp_Intr; use Exp_Intr;
42 with Exp_Pakd; use Exp_Pakd;
43 with Exp_Tss; use Exp_Tss;
44 with Exp_Util; use Exp_Util;
45 with Freeze; use Freeze;
46 with Inline; use Inline;
48 with Namet; use Namet;
49 with Nlists; use Nlists;
50 with Nmake; use Nmake;
52 with Par_SCO; use Par_SCO;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Aux; use Sem_Aux;
58 with Sem_Cat; use Sem_Cat;
59 with Sem_Ch3; use Sem_Ch3;
60 with Sem_Ch8; use Sem_Ch8;
61 with Sem_Ch13; use Sem_Ch13;
62 with Sem_Eval; use Sem_Eval;
63 with Sem_Res; use Sem_Res;
64 with Sem_Type; use Sem_Type;
65 with Sem_Util; use Sem_Util;
66 with Sem_Warn; use Sem_Warn;
67 with Sinfo; use Sinfo;
68 with Snames; use Snames;
69 with Stand; use Stand;
70 with SCIL_LL; use SCIL_LL;
71 with Targparm; use Targparm;
72 with Tbuild; use Tbuild;
73 with Ttypes; use Ttypes;
74 with Uintp; use Uintp;
75 with Urealp; use Urealp;
76 with Validsw; use Validsw;
78 package body Exp_Ch4 is
80 -----------------------
81 -- Local Subprograms --
82 -----------------------
84 procedure Binary_Op_Validity_Checks (N : Node_Id);
85 pragma Inline (Binary_Op_Validity_Checks);
86 -- Performs validity checks for a binary operator
88 procedure Build_Boolean_Array_Proc_Call
92 -- If a boolean array assignment can be done in place, build call to
93 -- corresponding library procedure.
95 function Current_Anonymous_Master return Entity_Id;
96 -- Return the entity of the heterogeneous finalization master belonging to
97 -- the current unit (either function, package or procedure). This master
98 -- services all anonymous access-to-controlled types. If the current unit
99 -- does not have such master, create one.
101 procedure Displace_Allocator_Pointer (N : Node_Id);
102 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
103 -- Expand_Allocator_Expression. Allocating class-wide interface objects
104 -- this routine displaces the pointer to the allocated object to reference
105 -- the component referencing the corresponding secondary dispatch table.
107 procedure Expand_Allocator_Expression (N : Node_Id);
108 -- Subsidiary to Expand_N_Allocator, for the case when the expression
109 -- is a qualified expression or an aggregate.
111 procedure Expand_Array_Comparison (N : Node_Id);
112 -- This routine handles expansion of the comparison operators (N_Op_Lt,
113 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
114 -- code for these operators is similar, differing only in the details of
115 -- the actual comparison call that is made. Special processing (call a
118 function Expand_Array_Equality
123 Typ : Entity_Id) return Node_Id;
124 -- Expand an array equality into a call to a function implementing this
125 -- equality, and a call to it. Loc is the location for the generated nodes.
126 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
127 -- on which to attach bodies of local functions that are created in the
128 -- process. It is the responsibility of the caller to insert those bodies
129 -- at the right place. Nod provides the Sloc value for the generated code.
130 -- Normally the types used for the generated equality routine are taken
131 -- from Lhs and Rhs. However, in some situations of generated code, the
132 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
133 -- the type to be used for the formal parameters.
135 procedure Expand_Boolean_Operator (N : Node_Id);
136 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
137 -- case of array type arguments.
139 procedure Expand_Short_Circuit_Operator (N : Node_Id);
140 -- Common expansion processing for short-circuit boolean operators
142 procedure Expand_Compare_Minimize_Eliminate_Overflow (N : Node_Id);
143 -- Deal with comparison in MINIMIZED/ELIMINATED overflow mode. This is
144 -- where we allow comparison of "out of range" values.
146 function Expand_Composite_Equality
151 Bodies : List_Id) return Node_Id;
152 -- Local recursive function used to expand equality for nested composite
153 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
154 -- to attach bodies of local functions that are created in the process. It
155 -- is the responsibility of the caller to insert those bodies at the right
156 -- place. Nod provides the Sloc value for generated code. Lhs and Rhs are
157 -- the left and right sides for the comparison, and Typ is the type of the
158 -- objects to compare.
160 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id);
161 -- Routine to expand concatenation of a sequence of two or more operands
162 -- (in the list Operands) and replace node Cnode with the result of the
163 -- concatenation. The operands can be of any appropriate type, and can
164 -- include both arrays and singleton elements.
166 procedure Expand_Membership_Minimize_Eliminate_Overflow (N : Node_Id);
167 -- N is an N_In membership test mode, with the overflow check mode set to
168 -- MINIMIZED or ELIMINATED, and the type of the left operand is a signed
169 -- integer type. This is a case where top level processing is required to
170 -- handle overflow checks in subtrees.
172 procedure Fixup_Universal_Fixed_Operation (N : Node_Id);
173 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
174 -- fixed. We do not have such a type at runtime, so the purpose of this
175 -- routine is to find the real type by looking up the tree. We also
176 -- determine if the operation must be rounded.
178 function Has_Inferable_Discriminants (N : Node_Id) return Boolean;
179 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
180 -- discriminants if it has a constrained nominal type, unless the object
181 -- is a component of an enclosing Unchecked_Union object that is subject
182 -- to a per-object constraint and the enclosing object lacks inferable
185 -- An expression of an Unchecked_Union type has inferable discriminants
186 -- if it is either a name of an object with inferable discriminants or a
187 -- qualified expression whose subtype mark denotes a constrained subtype.
189 procedure Insert_Dereference_Action (N : Node_Id);
190 -- N is an expression whose type is an access. When the type of the
191 -- associated storage pool is derived from Checked_Pool, generate a
192 -- call to the 'Dereference' primitive operation.
194 function Make_Array_Comparison_Op
196 Nod : Node_Id) return Node_Id;
197 -- Comparisons between arrays are expanded in line. This function produces
198 -- the body of the implementation of (a > b), where a and b are one-
199 -- dimensional arrays of some discrete type. The original node is then
200 -- expanded into the appropriate call to this function. Nod provides the
201 -- Sloc value for the generated code.
203 function Make_Boolean_Array_Op
205 N : Node_Id) return Node_Id;
206 -- Boolean operations on boolean arrays are expanded in line. This function
207 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
208 -- b). It is used only the normal case and not the packed case. The type
209 -- involved, Typ, is the Boolean array type, and the logical operations in
210 -- the body are simple boolean operations. Note that Typ is always a
211 -- constrained type (the caller has ensured this by using
212 -- Convert_To_Actual_Subtype if necessary).
214 function Minimized_Eliminated_Overflow_Check (N : Node_Id) return Boolean;
215 -- For signed arithmetic operations when the current overflow mode is
216 -- MINIMIZED or ELIMINATED, we must call Apply_Arithmetic_Overflow_Checks
217 -- as the first thing we do. We then return. We count on the recursive
218 -- apparatus for overflow checks to call us back with an equivalent
219 -- operation that is in CHECKED mode, avoiding a recursive entry into this
220 -- routine, and that is when we will proceed with the expansion of the
221 -- operator (e.g. converting X+0 to X, or X**2 to X*X). We cannot do
222 -- these optimizations without first making this check, since there may be
223 -- operands further down the tree that are relying on the recursive calls
224 -- triggered by the top level nodes to properly process overflow checking
225 -- and remaining expansion on these nodes. Note that this call back may be
226 -- skipped if the operation is done in Bignum mode but that's fine, since
227 -- the Bignum call takes care of everything.
229 procedure Optimize_Length_Comparison (N : Node_Id);
230 -- Given an expression, if it is of the form X'Length op N (or the other
231 -- way round), where N is known at compile time to be 0 or 1, and X is a
232 -- simple entity, and op is a comparison operator, optimizes it into a
233 -- comparison of First and Last.
235 procedure Process_Transient_Object
238 -- Subsidiary routine to the expansion of expression_with_actions and if
239 -- expressions. Generate all the necessary code to finalize a transient
240 -- controlled object when the enclosing context is elaborated or evaluated.
241 -- Decl denotes the declaration of the transient controlled object which is
242 -- usually the result of a controlled function call. Rel_Node denotes the
243 -- context, either an expression_with_actions or an if expression.
245 procedure Rewrite_Comparison (N : Node_Id);
246 -- If N is the node for a comparison whose outcome can be determined at
247 -- compile time, then the node N can be rewritten with True or False. If
248 -- the outcome cannot be determined at compile time, the call has no
249 -- effect. If N is a type conversion, then this processing is applied to
250 -- its expression. If N is neither comparison nor a type conversion, the
251 -- call has no effect.
253 procedure Tagged_Membership
255 SCIL_Node : out Node_Id;
256 Result : out Node_Id);
257 -- Construct the expression corresponding to the tagged membership test.
258 -- Deals with a second operand being (or not) a class-wide type.
260 function Safe_In_Place_Array_Op
263 Op2 : Node_Id) return Boolean;
264 -- In the context of an assignment, where the right-hand side is a boolean
265 -- operation on arrays, check whether operation can be performed in place.
267 procedure Unary_Op_Validity_Checks (N : Node_Id);
268 pragma Inline (Unary_Op_Validity_Checks);
269 -- Performs validity checks for a unary operator
271 -------------------------------
272 -- Binary_Op_Validity_Checks --
273 -------------------------------
275 procedure Binary_Op_Validity_Checks (N : Node_Id) is
277 if Validity_Checks_On and Validity_Check_Operands then
278 Ensure_Valid (Left_Opnd (N));
279 Ensure_Valid (Right_Opnd (N));
281 end Binary_Op_Validity_Checks;
283 ------------------------------------
284 -- Build_Boolean_Array_Proc_Call --
285 ------------------------------------
287 procedure Build_Boolean_Array_Proc_Call
292 Loc : constant Source_Ptr := Sloc (N);
293 Kind : constant Node_Kind := Nkind (Expression (N));
294 Target : constant Node_Id :=
295 Make_Attribute_Reference (Loc,
297 Attribute_Name => Name_Address);
299 Arg1 : Node_Id := Op1;
300 Arg2 : Node_Id := Op2;
302 Proc_Name : Entity_Id;
305 if Kind = N_Op_Not then
306 if Nkind (Op1) in N_Binary_Op then
308 -- Use negated version of the binary operators
310 if Nkind (Op1) = N_Op_And then
311 Proc_Name := RTE (RE_Vector_Nand);
313 elsif Nkind (Op1) = N_Op_Or then
314 Proc_Name := RTE (RE_Vector_Nor);
316 else pragma Assert (Nkind (Op1) = N_Op_Xor);
317 Proc_Name := RTE (RE_Vector_Xor);
321 Make_Procedure_Call_Statement (Loc,
322 Name => New_Occurrence_Of (Proc_Name, Loc),
324 Parameter_Associations => New_List (
326 Make_Attribute_Reference (Loc,
327 Prefix => Left_Opnd (Op1),
328 Attribute_Name => Name_Address),
330 Make_Attribute_Reference (Loc,
331 Prefix => Right_Opnd (Op1),
332 Attribute_Name => Name_Address),
334 Make_Attribute_Reference (Loc,
335 Prefix => Left_Opnd (Op1),
336 Attribute_Name => Name_Length)));
339 Proc_Name := RTE (RE_Vector_Not);
342 Make_Procedure_Call_Statement (Loc,
343 Name => New_Occurrence_Of (Proc_Name, Loc),
344 Parameter_Associations => New_List (
347 Make_Attribute_Reference (Loc,
349 Attribute_Name => Name_Address),
351 Make_Attribute_Reference (Loc,
353 Attribute_Name => Name_Length)));
357 -- We use the following equivalences:
359 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
360 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
361 -- (not X) xor (not Y) = X xor Y
362 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
364 if Nkind (Op1) = N_Op_Not then
365 Arg1 := Right_Opnd (Op1);
366 Arg2 := Right_Opnd (Op2);
368 if Kind = N_Op_And then
369 Proc_Name := RTE (RE_Vector_Nor);
370 elsif Kind = N_Op_Or then
371 Proc_Name := RTE (RE_Vector_Nand);
373 Proc_Name := RTE (RE_Vector_Xor);
377 if Kind = N_Op_And then
378 Proc_Name := RTE (RE_Vector_And);
379 elsif Kind = N_Op_Or then
380 Proc_Name := RTE (RE_Vector_Or);
381 elsif Nkind (Op2) = N_Op_Not then
382 Proc_Name := RTE (RE_Vector_Nxor);
383 Arg2 := Right_Opnd (Op2);
385 Proc_Name := RTE (RE_Vector_Xor);
390 Make_Procedure_Call_Statement (Loc,
391 Name => New_Occurrence_Of (Proc_Name, Loc),
392 Parameter_Associations => New_List (
394 Make_Attribute_Reference (Loc,
396 Attribute_Name => Name_Address),
397 Make_Attribute_Reference (Loc,
399 Attribute_Name => Name_Address),
400 Make_Attribute_Reference (Loc,
402 Attribute_Name => Name_Length)));
405 Rewrite (N, Call_Node);
409 when RE_Not_Available =>
411 end Build_Boolean_Array_Proc_Call;
413 ------------------------------
414 -- Current_Anonymous_Master --
415 ------------------------------
417 function Current_Anonymous_Master return Entity_Id is
425 Unit_Id := Cunit_Entity (Current_Sem_Unit);
427 -- Find the entity of the current unit
429 if Ekind (Unit_Id) = E_Subprogram_Body then
431 -- When processing subprogram bodies, the proper scope is always that
434 Subp_Body := Unit_Id;
435 while Present (Subp_Body)
436 and then Nkind (Subp_Body) /= N_Subprogram_Body
438 Subp_Body := Parent (Subp_Body);
441 Unit_Id := Corresponding_Spec (Subp_Body);
444 Loc := Sloc (Unit_Id);
445 Unit_Decl := Unit (Cunit (Current_Sem_Unit));
447 -- Find the declarations list of the current unit
449 if Nkind (Unit_Decl) = N_Package_Declaration then
450 Unit_Decl := Specification (Unit_Decl);
451 Decls := Visible_Declarations (Unit_Decl);
454 Decls := New_List (Make_Null_Statement (Loc));
455 Set_Visible_Declarations (Unit_Decl, Decls);
457 elsif Is_Empty_List (Decls) then
458 Append_To (Decls, Make_Null_Statement (Loc));
462 Decls := Declarations (Unit_Decl);
465 Decls := New_List (Make_Null_Statement (Loc));
466 Set_Declarations (Unit_Decl, Decls);
468 elsif Is_Empty_List (Decls) then
469 Append_To (Decls, Make_Null_Statement (Loc));
473 -- The current unit has an existing anonymous master, traverse its
474 -- declarations and locate the entity.
476 if Has_Anonymous_Master (Unit_Id) then
479 Fin_Mas_Id : Entity_Id;
482 Decl := First (Decls);
483 while Present (Decl) loop
485 -- Look for the first variable in the declarations whole type
486 -- is Finalization_Master.
488 if Nkind (Decl) = N_Object_Declaration then
489 Fin_Mas_Id := Defining_Identifier (Decl);
491 if Ekind (Fin_Mas_Id) = E_Variable
492 and then Etype (Fin_Mas_Id) = RTE (RE_Finalization_Master)
501 -- The master was not found even though the unit was labeled as
507 -- Create a new anonymous master
511 First_Decl : constant Node_Id := First (Decls);
513 Fin_Mas_Id : Entity_Id;
516 -- Since the master and its associated initialization is inserted
517 -- at top level, use the scope of the unit when analyzing.
519 Push_Scope (Unit_Id);
521 -- Create the finalization master
524 Make_Defining_Identifier (Loc,
525 Chars => New_External_Name (Chars (Unit_Id), "AM"));
528 -- <Fin_Mas_Id> : Finalization_Master;
531 Make_Object_Declaration (Loc,
532 Defining_Identifier => Fin_Mas_Id,
534 New_Occurrence_Of (RTE (RE_Finalization_Master), Loc));
536 Insert_Before_And_Analyze (First_Decl, Action);
538 -- Mark the unit to prevent the generation of multiple masters
540 Set_Has_Anonymous_Master (Unit_Id);
542 -- Do not set the base pool and mode of operation on .NET/JVM
543 -- since those targets do not support pools and all VM masters
544 -- are heterogeneous by default.
546 if VM_Target = No_VM then
550 -- (<Fin_Mas_Id>, Global_Pool_Object'Unrestricted_Access);
553 Make_Procedure_Call_Statement (Loc,
555 New_Occurrence_Of (RTE (RE_Set_Base_Pool), Loc),
557 Parameter_Associations => New_List (
558 New_Occurrence_Of (Fin_Mas_Id, Loc),
559 Make_Attribute_Reference (Loc,
561 New_Occurrence_Of (RTE (RE_Global_Pool_Object), Loc),
562 Attribute_Name => Name_Unrestricted_Access)));
564 Insert_Before_And_Analyze (First_Decl, Action);
567 -- Set_Is_Heterogeneous (<Fin_Mas_Id>);
570 Make_Procedure_Call_Statement (Loc,
572 New_Occurrence_Of (RTE (RE_Set_Is_Heterogeneous), Loc),
573 Parameter_Associations => New_List (
574 New_Occurrence_Of (Fin_Mas_Id, Loc)));
576 Insert_Before_And_Analyze (First_Decl, Action);
579 -- Restore the original state of the scope stack
586 end Current_Anonymous_Master;
588 --------------------------------
589 -- Displace_Allocator_Pointer --
590 --------------------------------
592 procedure Displace_Allocator_Pointer (N : Node_Id) is
593 Loc : constant Source_Ptr := Sloc (N);
594 Orig_Node : constant Node_Id := Original_Node (N);
600 -- Do nothing in case of VM targets: the virtual machine will handle
601 -- interfaces directly.
603 if not Tagged_Type_Expansion then
607 pragma Assert (Nkind (N) = N_Identifier
608 and then Nkind (Orig_Node) = N_Allocator);
610 PtrT := Etype (Orig_Node);
611 Dtyp := Available_View (Designated_Type (PtrT));
612 Etyp := Etype (Expression (Orig_Node));
614 if Is_Class_Wide_Type (Dtyp) and then Is_Interface (Dtyp) then
616 -- If the type of the allocator expression is not an interface type
617 -- we can generate code to reference the record component containing
618 -- the pointer to the secondary dispatch table.
620 if not Is_Interface (Etyp) then
622 Saved_Typ : constant Entity_Id := Etype (Orig_Node);
625 -- 1) Get access to the allocated object
628 Make_Explicit_Dereference (Loc, Relocate_Node (N)));
632 -- 2) Add the conversion to displace the pointer to reference
633 -- the secondary dispatch table.
635 Rewrite (N, Convert_To (Dtyp, Relocate_Node (N)));
636 Analyze_And_Resolve (N, Dtyp);
638 -- 3) The 'access to the secondary dispatch table will be used
639 -- as the value returned by the allocator.
642 Make_Attribute_Reference (Loc,
643 Prefix => Relocate_Node (N),
644 Attribute_Name => Name_Access));
645 Set_Etype (N, Saved_Typ);
649 -- If the type of the allocator expression is an interface type we
650 -- generate a run-time call to displace "this" to reference the
651 -- component containing the pointer to the secondary dispatch table
652 -- or else raise Constraint_Error if the actual object does not
653 -- implement the target interface. This case corresponds to the
654 -- following example:
656 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
658 -- return new Iface_2'Class'(Obj);
663 Unchecked_Convert_To (PtrT,
664 Make_Function_Call (Loc,
665 Name => New_Occurrence_Of (RTE (RE_Displace), Loc),
666 Parameter_Associations => New_List (
667 Unchecked_Convert_To (RTE (RE_Address),
673 (Access_Disp_Table (Etype (Base_Type (Dtyp))))),
675 Analyze_And_Resolve (N, PtrT);
678 end Displace_Allocator_Pointer;
680 ---------------------------------
681 -- Expand_Allocator_Expression --
682 ---------------------------------
684 procedure Expand_Allocator_Expression (N : Node_Id) is
685 Loc : constant Source_Ptr := Sloc (N);
686 Exp : constant Node_Id := Expression (Expression (N));
687 PtrT : constant Entity_Id := Etype (N);
688 DesigT : constant Entity_Id := Designated_Type (PtrT);
690 procedure Apply_Accessibility_Check
692 Built_In_Place : Boolean := False);
693 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
694 -- type, generate an accessibility check to verify that the level of the
695 -- type of the created object is not deeper than the level of the access
696 -- type. If the type of the qualified expression is class-wide, then
697 -- always generate the check (except in the case where it is known to be
698 -- unnecessary, see comment below). Otherwise, only generate the check
699 -- if the level of the qualified expression type is statically deeper
700 -- than the access type.
702 -- Although the static accessibility will generally have been performed
703 -- as a legality check, it won't have been done in cases where the
704 -- allocator appears in generic body, so a run-time check is needed in
705 -- general. One special case is when the access type is declared in the
706 -- same scope as the class-wide allocator, in which case the check can
707 -- never fail, so it need not be generated.
709 -- As an open issue, there seem to be cases where the static level
710 -- associated with the class-wide object's underlying type is not
711 -- sufficient to perform the proper accessibility check, such as for
712 -- allocators in nested subprograms or accept statements initialized by
713 -- class-wide formals when the actual originates outside at a deeper
714 -- static level. The nested subprogram case might require passing
715 -- accessibility levels along with class-wide parameters, and the task
716 -- case seems to be an actual gap in the language rules that needs to
717 -- be fixed by the ARG. ???
719 -------------------------------
720 -- Apply_Accessibility_Check --
721 -------------------------------
723 procedure Apply_Accessibility_Check
725 Built_In_Place : Boolean := False)
727 Pool_Id : constant Entity_Id := Associated_Storage_Pool (PtrT);
735 if Ada_Version >= Ada_2005
736 and then Is_Class_Wide_Type (DesigT)
737 and then (Tagged_Type_Expansion or else VM_Target /= No_VM)
738 and then not Scope_Suppress.Suppress (Accessibility_Check)
740 (Type_Access_Level (Etype (Exp)) > Type_Access_Level (PtrT)
742 (Is_Class_Wide_Type (Etype (Exp))
743 and then Scope (PtrT) /= Current_Scope))
745 -- If the allocator was built in place, Ref is already a reference
746 -- to the access object initialized to the result of the allocator
747 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). We call
748 -- Remove_Side_Effects for cases where the build-in-place call may
749 -- still be the prefix of the reference (to avoid generating
750 -- duplicate calls). Otherwise, it is the entity associated with
751 -- the object containing the address of the allocated object.
753 if Built_In_Place then
754 Remove_Side_Effects (Ref);
755 Obj_Ref := New_Copy_Tree (Ref);
757 Obj_Ref := New_Occurrence_Of (Ref, Loc);
760 -- For access to interface types we must generate code to displace
761 -- the pointer to the base of the object since the subsequent code
762 -- references components located in the TSD of the object (which
763 -- is associated with the primary dispatch table --see a-tags.ads)
764 -- and also generates code invoking Free, which requires also a
765 -- reference to the base of the unallocated object.
767 if Is_Interface (DesigT) and then Tagged_Type_Expansion then
769 Unchecked_Convert_To (Etype (Obj_Ref),
770 Make_Function_Call (Loc,
772 New_Occurrence_Of (RTE (RE_Base_Address), Loc),
773 Parameter_Associations => New_List (
774 Unchecked_Convert_To (RTE (RE_Address),
775 New_Copy_Tree (Obj_Ref)))));
778 -- Step 1: Create the object clean up code
782 -- Deallocate the object if the accessibility check fails. This
783 -- is done only on targets or profiles that support deallocation.
787 if RTE_Available (RE_Free) then
788 Free_Stmt := Make_Free_Statement (Loc, New_Copy_Tree (Obj_Ref));
789 Set_Storage_Pool (Free_Stmt, Pool_Id);
791 Append_To (Stmts, Free_Stmt);
793 -- The target or profile cannot deallocate objects
799 -- Finalize the object if applicable. Generate:
801 -- [Deep_]Finalize (Obj_Ref.all);
803 if Needs_Finalization (DesigT) then
807 Make_Explicit_Dereference (Loc, New_Copy (Obj_Ref)),
810 -- When the target or profile supports deallocation, wrap the
811 -- finalization call in a block to ensure proper deallocation
812 -- even if finalization fails. Generate:
822 if Present (Free_Stmt) then
824 Make_Block_Statement (Loc,
825 Handled_Statement_Sequence =>
826 Make_Handled_Sequence_Of_Statements (Loc,
827 Statements => New_List (Fin_Call),
829 Exception_Handlers => New_List (
830 Make_Exception_Handler (Loc,
831 Exception_Choices => New_List (
832 Make_Others_Choice (Loc)),
834 Statements => New_List (
835 New_Copy_Tree (Free_Stmt),
836 Make_Raise_Statement (Loc))))));
839 Prepend_To (Stmts, Fin_Call);
842 -- Signal the accessibility failure through a Program_Error
845 Make_Raise_Program_Error (Loc,
846 Condition => New_Occurrence_Of (Standard_True, Loc),
847 Reason => PE_Accessibility_Check_Failed));
849 -- Step 2: Create the accessibility comparison
855 Make_Attribute_Reference (Loc,
857 Attribute_Name => Name_Tag);
859 -- For tagged types, determine the accessibility level by looking
860 -- at the type specific data of the dispatch table. Generate:
862 -- Type_Specific_Data (Address (Ref'Tag)).Access_Level
864 if Tagged_Type_Expansion then
865 Cond := Build_Get_Access_Level (Loc, Obj_Ref);
867 -- Use a runtime call to determine the accessibility level when
868 -- compiling on virtual machine targets. Generate:
870 -- Get_Access_Level (Ref'Tag)
874 Make_Function_Call (Loc,
876 New_Occurrence_Of (RTE (RE_Get_Access_Level), Loc),
877 Parameter_Associations => New_List (Obj_Ref));
884 Make_Integer_Literal (Loc, Type_Access_Level (PtrT)));
886 -- Due to the complexity and side effects of the check, utilize an
887 -- if statement instead of the regular Program_Error circuitry.
890 Make_Implicit_If_Statement (N,
892 Then_Statements => Stmts));
894 end Apply_Accessibility_Check;
898 Aggr_In_Place : constant Boolean := Is_Delayed_Aggregate (Exp);
899 Indic : constant Node_Id := Subtype_Mark (Expression (N));
900 T : constant Entity_Id := Entity (Indic);
902 Tag_Assign : Node_Id;
906 TagT : Entity_Id := Empty;
907 -- Type used as source for tag assignment
909 TagR : Node_Id := Empty;
910 -- Target reference for tag assignment
912 -- Start of processing for Expand_Allocator_Expression
915 -- Handle call to C++ constructor
917 if Is_CPP_Constructor_Call (Exp) then
918 Make_CPP_Constructor_Call_In_Allocator
920 Function_Call => Exp);
924 -- In the case of an Ada 2012 allocator whose initial value comes from a
925 -- function call, pass "the accessibility level determined by the point
926 -- of call" (AI05-0234) to the function. Conceptually, this belongs in
927 -- Expand_Call but it couldn't be done there (because the Etype of the
928 -- allocator wasn't set then) so we generate the parameter here. See
929 -- the Boolean variable Defer in (a block within) Expand_Call.
931 if Ada_Version >= Ada_2012 and then Nkind (Exp) = N_Function_Call then
936 if Nkind (Name (Exp)) = N_Explicit_Dereference then
937 Subp := Designated_Type (Etype (Prefix (Name (Exp))));
939 Subp := Entity (Name (Exp));
942 Subp := Ultimate_Alias (Subp);
944 if Present (Extra_Accessibility_Of_Result (Subp)) then
945 Add_Extra_Actual_To_Call
946 (Subprogram_Call => Exp,
947 Extra_Formal => Extra_Accessibility_Of_Result (Subp),
948 Extra_Actual => Dynamic_Accessibility_Level (PtrT));
953 -- Case of tagged type or type requiring finalization
955 if Is_Tagged_Type (T) or else Needs_Finalization (T) then
957 -- Ada 2005 (AI-318-02): If the initialization expression is a call
958 -- to a build-in-place function, then access to the allocated object
959 -- must be passed to the function. Currently we limit such functions
960 -- to those with constrained limited result subtypes, but eventually
961 -- we plan to expand the allowed forms of functions that are treated
962 -- as build-in-place.
964 if Ada_Version >= Ada_2005
965 and then Is_Build_In_Place_Function_Call (Exp)
967 Make_Build_In_Place_Call_In_Allocator (N, Exp);
968 Apply_Accessibility_Check (N, Built_In_Place => True);
972 -- Actions inserted before:
973 -- Temp : constant ptr_T := new T'(Expression);
974 -- Temp._tag = T'tag; -- when not class-wide
975 -- [Deep_]Adjust (Temp.all);
977 -- We analyze by hand the new internal allocator to avoid any
978 -- recursion and inappropriate call to Initialize.
980 -- We don't want to remove side effects when the expression must be
981 -- built in place. In the case of a build-in-place function call,
982 -- that could lead to a duplication of the call, which was already
983 -- substituted for the allocator.
985 if not Aggr_In_Place then
986 Remove_Side_Effects (Exp);
989 Temp := Make_Temporary (Loc, 'P', N);
991 -- For a class wide allocation generate the following code:
993 -- type Equiv_Record is record ... end record;
994 -- implicit subtype CW is <Class_Wide_Subytpe>;
995 -- temp : PtrT := new CW'(CW!(expr));
997 if Is_Class_Wide_Type (T) then
998 Expand_Subtype_From_Expr (Empty, T, Indic, Exp);
1000 -- Ada 2005 (AI-251): If the expression is a class-wide interface
1001 -- object we generate code to move up "this" to reference the
1002 -- base of the object before allocating the new object.
1004 -- Note that Exp'Address is recursively expanded into a call
1005 -- to Base_Address (Exp.Tag)
1007 if Is_Class_Wide_Type (Etype (Exp))
1008 and then Is_Interface (Etype (Exp))
1009 and then Tagged_Type_Expansion
1013 Unchecked_Convert_To (Entity (Indic),
1014 Make_Explicit_Dereference (Loc,
1015 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
1016 Make_Attribute_Reference (Loc,
1018 Attribute_Name => Name_Address)))));
1022 Unchecked_Convert_To (Entity (Indic), Exp));
1025 Analyze_And_Resolve (Expression (N), Entity (Indic));
1028 -- Processing for allocators returning non-interface types
1030 if not Is_Interface (Directly_Designated_Type (PtrT)) then
1031 if Aggr_In_Place then
1033 Make_Object_Declaration (Loc,
1034 Defining_Identifier => Temp,
1035 Object_Definition => New_Occurrence_Of (PtrT, Loc),
1037 Make_Allocator (Loc,
1039 New_Occurrence_Of (Etype (Exp), Loc)));
1041 -- Copy the Comes_From_Source flag for the allocator we just
1042 -- built, since logically this allocator is a replacement of
1043 -- the original allocator node. This is for proper handling of
1044 -- restriction No_Implicit_Heap_Allocations.
1046 Set_Comes_From_Source
1047 (Expression (Temp_Decl), Comes_From_Source (N));
1049 Set_No_Initialization (Expression (Temp_Decl));
1050 Insert_Action (N, Temp_Decl);
1052 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1053 Convert_Aggr_In_Allocator (N, Temp_Decl, Exp);
1055 -- Attach the object to the associated finalization master.
1056 -- This is done manually on .NET/JVM since those compilers do
1057 -- no support pools and can't benefit from internally generated
1058 -- Allocate / Deallocate procedures.
1060 if VM_Target /= No_VM
1061 and then Is_Controlled (DesigT)
1062 and then Present (Finalization_Master (PtrT))
1066 (Obj_Ref => New_Occurrence_Of (Temp, Loc),
1071 Node := Relocate_Node (N);
1072 Set_Analyzed (Node);
1075 Make_Object_Declaration (Loc,
1076 Defining_Identifier => Temp,
1077 Constant_Present => True,
1078 Object_Definition => New_Occurrence_Of (PtrT, Loc),
1079 Expression => Node);
1081 Insert_Action (N, Temp_Decl);
1082 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1084 -- Attach the object to the associated finalization master.
1085 -- This is done manually on .NET/JVM since those compilers do
1086 -- no support pools and can't benefit from internally generated
1087 -- Allocate / Deallocate procedures.
1089 if VM_Target /= No_VM
1090 and then Is_Controlled (DesigT)
1091 and then Present (Finalization_Master (PtrT))
1095 (Obj_Ref => New_Occurrence_Of (Temp, Loc),
1100 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
1101 -- interface type. In this case we use the type of the qualified
1102 -- expression to allocate the object.
1106 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'T');
1111 Make_Full_Type_Declaration (Loc,
1112 Defining_Identifier => Def_Id,
1114 Make_Access_To_Object_Definition (Loc,
1115 All_Present => True,
1116 Null_Exclusion_Present => False,
1118 Is_Access_Constant (Etype (N)),
1119 Subtype_Indication =>
1120 New_Occurrence_Of (Etype (Exp), Loc)));
1122 Insert_Action (N, New_Decl);
1124 -- Inherit the allocation-related attributes from the original
1127 Set_Finalization_Master
1128 (Def_Id, Finalization_Master (PtrT));
1130 Set_Associated_Storage_Pool
1131 (Def_Id, Associated_Storage_Pool (PtrT));
1133 -- Declare the object using the previous type declaration
1135 if Aggr_In_Place then
1137 Make_Object_Declaration (Loc,
1138 Defining_Identifier => Temp,
1139 Object_Definition => New_Occurrence_Of (Def_Id, Loc),
1141 Make_Allocator (Loc,
1142 New_Occurrence_Of (Etype (Exp), Loc)));
1144 -- Copy the Comes_From_Source flag for the allocator we just
1145 -- built, since logically this allocator is a replacement of
1146 -- the original allocator node. This is for proper handling
1147 -- of restriction No_Implicit_Heap_Allocations.
1149 Set_Comes_From_Source
1150 (Expression (Temp_Decl), Comes_From_Source (N));
1152 Set_No_Initialization (Expression (Temp_Decl));
1153 Insert_Action (N, Temp_Decl);
1155 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1156 Convert_Aggr_In_Allocator (N, Temp_Decl, Exp);
1159 Node := Relocate_Node (N);
1160 Set_Analyzed (Node);
1163 Make_Object_Declaration (Loc,
1164 Defining_Identifier => Temp,
1165 Constant_Present => True,
1166 Object_Definition => New_Occurrence_Of (Def_Id, Loc),
1167 Expression => Node);
1169 Insert_Action (N, Temp_Decl);
1170 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1173 -- Generate an additional object containing the address of the
1174 -- returned object. The type of this second object declaration
1175 -- is the correct type required for the common processing that
1176 -- is still performed by this subprogram. The displacement of
1177 -- this pointer to reference the component associated with the
1178 -- interface type will be done at the end of common processing.
1181 Make_Object_Declaration (Loc,
1182 Defining_Identifier => Make_Temporary (Loc, 'P'),
1183 Object_Definition => New_Occurrence_Of (PtrT, Loc),
1185 Unchecked_Convert_To (PtrT,
1186 New_Occurrence_Of (Temp, Loc)));
1188 Insert_Action (N, New_Decl);
1190 Temp_Decl := New_Decl;
1191 Temp := Defining_Identifier (New_Decl);
1195 Apply_Accessibility_Check (Temp);
1197 -- Generate the tag assignment
1199 -- Suppress the tag assignment when VM_Target because VM tags are
1200 -- represented implicitly in objects.
1202 if not Tagged_Type_Expansion then
1205 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
1206 -- interface objects because in this case the tag does not change.
1208 elsif Is_Interface (Directly_Designated_Type (Etype (N))) then
1209 pragma Assert (Is_Class_Wide_Type
1210 (Directly_Designated_Type (Etype (N))));
1213 elsif Is_Tagged_Type (T) and then not Is_Class_Wide_Type (T) then
1215 TagR := New_Occurrence_Of (Temp, Loc);
1217 elsif Is_Private_Type (T)
1218 and then Is_Tagged_Type (Underlying_Type (T))
1220 TagT := Underlying_Type (T);
1222 Unchecked_Convert_To (Underlying_Type (T),
1223 Make_Explicit_Dereference (Loc,
1224 Prefix => New_Occurrence_Of (Temp, Loc)));
1227 if Present (TagT) then
1229 Full_T : constant Entity_Id := Underlying_Type (TagT);
1233 Make_Assignment_Statement (Loc,
1235 Make_Selected_Component (Loc,
1239 (First_Tag_Component (Full_T), Loc)),
1242 Unchecked_Convert_To (RTE (RE_Tag),
1245 (First_Elmt (Access_Disp_Table (Full_T))), Loc)));
1248 -- The previous assignment has to be done in any case
1250 Set_Assignment_OK (Name (Tag_Assign));
1251 Insert_Action (N, Tag_Assign);
1254 if Needs_Finalization (DesigT) and then Needs_Finalization (T) then
1256 -- Generate an Adjust call if the object will be moved. In Ada
1257 -- 2005, the object may be inherently limited, in which case
1258 -- there is no Adjust procedure, and the object is built in
1259 -- place. In Ada 95, the object can be limited but not
1260 -- inherently limited if this allocator came from a return
1261 -- statement (we're allocating the result on the secondary
1262 -- stack). In that case, the object will be moved, so we _do_
1265 if not Aggr_In_Place
1266 and then not Is_Limited_View (T)
1270 -- An unchecked conversion is needed in the classwide case
1271 -- because the designated type can be an ancestor of the
1272 -- subtype mark of the allocator.
1276 Unchecked_Convert_To (T,
1277 Make_Explicit_Dereference (Loc,
1278 Prefix => New_Occurrence_Of (Temp, Loc))),
1283 -- Set_Finalize_Address (<PtrT>FM, <T>FD'Unrestricted_Access);
1285 -- Do not generate this call in the following cases:
1287 -- * .NET/JVM - these targets do not support address arithmetic
1288 -- and unchecked conversion, key elements of Finalize_Address.
1290 -- * CodePeer mode - TSS primitive Finalize_Address is not
1291 -- created in this mode.
1293 if VM_Target = No_VM
1294 and then not CodePeer_Mode
1295 and then Present (Finalization_Master (PtrT))
1296 and then Present (Temp_Decl)
1297 and then Nkind (Expression (Temp_Decl)) = N_Allocator
1300 Make_Set_Finalize_Address_Call
1307 Rewrite (N, New_Occurrence_Of (Temp, Loc));
1308 Analyze_And_Resolve (N, PtrT);
1310 -- Ada 2005 (AI-251): Displace the pointer to reference the record
1311 -- component containing the secondary dispatch table of the interface
1314 if Is_Interface (Directly_Designated_Type (PtrT)) then
1315 Displace_Allocator_Pointer (N);
1318 elsif Aggr_In_Place then
1319 Temp := Make_Temporary (Loc, 'P', N);
1321 Make_Object_Declaration (Loc,
1322 Defining_Identifier => Temp,
1323 Object_Definition => New_Occurrence_Of (PtrT, Loc),
1325 Make_Allocator (Loc,
1326 Expression => New_Occurrence_Of (Etype (Exp), Loc)));
1328 -- Copy the Comes_From_Source flag for the allocator we just built,
1329 -- since logically this allocator is a replacement of the original
1330 -- allocator node. This is for proper handling of restriction
1331 -- No_Implicit_Heap_Allocations.
1333 Set_Comes_From_Source
1334 (Expression (Temp_Decl), Comes_From_Source (N));
1336 Set_No_Initialization (Expression (Temp_Decl));
1337 Insert_Action (N, Temp_Decl);
1339 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1340 Convert_Aggr_In_Allocator (N, Temp_Decl, Exp);
1342 -- Attach the object to the associated finalization master. Thisis
1343 -- done manually on .NET/JVM since those compilers do no support
1344 -- pools and cannot benefit from internally generated Allocate and
1345 -- Deallocate procedures.
1347 if VM_Target /= No_VM
1348 and then Is_Controlled (DesigT)
1349 and then Present (Finalization_Master (PtrT))
1353 (Obj_Ref => New_Occurrence_Of (Temp, Loc),
1357 Rewrite (N, New_Occurrence_Of (Temp, Loc));
1358 Analyze_And_Resolve (N, PtrT);
1360 elsif Is_Access_Type (T) and then Can_Never_Be_Null (T) then
1361 Install_Null_Excluding_Check (Exp);
1363 elsif Is_Access_Type (DesigT)
1364 and then Nkind (Exp) = N_Allocator
1365 and then Nkind (Expression (Exp)) /= N_Qualified_Expression
1367 -- Apply constraint to designated subtype indication
1369 Apply_Constraint_Check
1370 (Expression (Exp), Designated_Type (DesigT), No_Sliding => True);
1372 if Nkind (Expression (Exp)) = N_Raise_Constraint_Error then
1374 -- Propagate constraint_error to enclosing allocator
1376 Rewrite (Exp, New_Copy (Expression (Exp)));
1380 Build_Allocate_Deallocate_Proc (N, True);
1383 -- type A is access T1;
1384 -- X : A := new T2'(...);
1385 -- T1 and T2 can be different subtypes, and we might need to check
1386 -- both constraints. First check against the type of the qualified
1389 Apply_Constraint_Check (Exp, T, No_Sliding => True);
1391 if Do_Range_Check (Exp) then
1392 Generate_Range_Check (Exp, DesigT, CE_Range_Check_Failed);
1395 -- A check is also needed in cases where the designated subtype is
1396 -- constrained and differs from the subtype given in the qualified
1397 -- expression. Note that the check on the qualified expression does
1398 -- not allow sliding, but this check does (a relaxation from Ada 83).
1400 if Is_Constrained (DesigT)
1401 and then not Subtypes_Statically_Match (T, DesigT)
1403 Apply_Constraint_Check
1404 (Exp, DesigT, No_Sliding => False);
1406 if Do_Range_Check (Exp) then
1407 Generate_Range_Check (Exp, DesigT, CE_Range_Check_Failed);
1411 -- For an access to unconstrained packed array, GIGI needs to see an
1412 -- expression with a constrained subtype in order to compute the
1413 -- proper size for the allocator.
1415 if Is_Array_Type (T)
1416 and then not Is_Constrained (T)
1417 and then Is_Packed (T)
1420 ConstrT : constant Entity_Id := Make_Temporary (Loc, 'A');
1421 Internal_Exp : constant Node_Id := Relocate_Node (Exp);
1424 Make_Subtype_Declaration (Loc,
1425 Defining_Identifier => ConstrT,
1426 Subtype_Indication =>
1427 Make_Subtype_From_Expr (Internal_Exp, T)));
1428 Freeze_Itype (ConstrT, Exp);
1429 Rewrite (Exp, OK_Convert_To (ConstrT, Internal_Exp));
1433 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1434 -- to a build-in-place function, then access to the allocated object
1435 -- must be passed to the function. Currently we limit such functions
1436 -- to those with constrained limited result subtypes, but eventually
1437 -- we plan to expand the allowed forms of functions that are treated
1438 -- as build-in-place.
1440 if Ada_Version >= Ada_2005
1441 and then Is_Build_In_Place_Function_Call (Exp)
1443 Make_Build_In_Place_Call_In_Allocator (N, Exp);
1448 when RE_Not_Available =>
1450 end Expand_Allocator_Expression;
1452 -----------------------------
1453 -- Expand_Array_Comparison --
1454 -----------------------------
1456 -- Expansion is only required in the case of array types. For the unpacked
1457 -- case, an appropriate runtime routine is called. For packed cases, and
1458 -- also in some other cases where a runtime routine cannot be called, the
1459 -- form of the expansion is:
1461 -- [body for greater_nn; boolean_expression]
1463 -- The body is built by Make_Array_Comparison_Op, and the form of the
1464 -- Boolean expression depends on the operator involved.
1466 procedure Expand_Array_Comparison (N : Node_Id) is
1467 Loc : constant Source_Ptr := Sloc (N);
1468 Op1 : Node_Id := Left_Opnd (N);
1469 Op2 : Node_Id := Right_Opnd (N);
1470 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
1471 Ctyp : constant Entity_Id := Component_Type (Typ1);
1474 Func_Body : Node_Id;
1475 Func_Name : Entity_Id;
1479 Byte_Addressable : constant Boolean := System_Storage_Unit = Byte'Size;
1480 -- True for byte addressable target
1482 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean;
1483 -- Returns True if the length of the given operand is known to be less
1484 -- than 4. Returns False if this length is known to be four or greater
1485 -- or is not known at compile time.
1487 ------------------------
1488 -- Length_Less_Than_4 --
1489 ------------------------
1491 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean is
1492 Otyp : constant Entity_Id := Etype (Opnd);
1495 if Ekind (Otyp) = E_String_Literal_Subtype then
1496 return String_Literal_Length (Otyp) < 4;
1500 Ityp : constant Entity_Id := Etype (First_Index (Otyp));
1501 Lo : constant Node_Id := Type_Low_Bound (Ityp);
1502 Hi : constant Node_Id := Type_High_Bound (Ityp);
1507 if Compile_Time_Known_Value (Lo) then
1508 Lov := Expr_Value (Lo);
1513 if Compile_Time_Known_Value (Hi) then
1514 Hiv := Expr_Value (Hi);
1519 return Hiv < Lov + 3;
1522 end Length_Less_Than_4;
1524 -- Start of processing for Expand_Array_Comparison
1527 -- Deal first with unpacked case, where we can call a runtime routine
1528 -- except that we avoid this for targets for which are not addressable
1529 -- by bytes, and for the JVM/CIL, since they do not support direct
1530 -- addressing of array components.
1532 if not Is_Bit_Packed_Array (Typ1)
1533 and then Byte_Addressable
1534 and then VM_Target = No_VM
1536 -- The call we generate is:
1538 -- Compare_Array_xn[_Unaligned]
1539 -- (left'address, right'address, left'length, right'length) <op> 0
1541 -- x = U for unsigned, S for signed
1542 -- n = 8,16,32,64 for component size
1543 -- Add _Unaligned if length < 4 and component size is 8.
1544 -- <op> is the standard comparison operator
1546 if Component_Size (Typ1) = 8 then
1547 if Length_Less_Than_4 (Op1)
1549 Length_Less_Than_4 (Op2)
1551 if Is_Unsigned_Type (Ctyp) then
1552 Comp := RE_Compare_Array_U8_Unaligned;
1554 Comp := RE_Compare_Array_S8_Unaligned;
1558 if Is_Unsigned_Type (Ctyp) then
1559 Comp := RE_Compare_Array_U8;
1561 Comp := RE_Compare_Array_S8;
1565 elsif Component_Size (Typ1) = 16 then
1566 if Is_Unsigned_Type (Ctyp) then
1567 Comp := RE_Compare_Array_U16;
1569 Comp := RE_Compare_Array_S16;
1572 elsif Component_Size (Typ1) = 32 then
1573 if Is_Unsigned_Type (Ctyp) then
1574 Comp := RE_Compare_Array_U32;
1576 Comp := RE_Compare_Array_S32;
1579 else pragma Assert (Component_Size (Typ1) = 64);
1580 if Is_Unsigned_Type (Ctyp) then
1581 Comp := RE_Compare_Array_U64;
1583 Comp := RE_Compare_Array_S64;
1587 Remove_Side_Effects (Op1, Name_Req => True);
1588 Remove_Side_Effects (Op2, Name_Req => True);
1591 Make_Function_Call (Sloc (Op1),
1592 Name => New_Occurrence_Of (RTE (Comp), Loc),
1594 Parameter_Associations => New_List (
1595 Make_Attribute_Reference (Loc,
1596 Prefix => Relocate_Node (Op1),
1597 Attribute_Name => Name_Address),
1599 Make_Attribute_Reference (Loc,
1600 Prefix => Relocate_Node (Op2),
1601 Attribute_Name => Name_Address),
1603 Make_Attribute_Reference (Loc,
1604 Prefix => Relocate_Node (Op1),
1605 Attribute_Name => Name_Length),
1607 Make_Attribute_Reference (Loc,
1608 Prefix => Relocate_Node (Op2),
1609 Attribute_Name => Name_Length))));
1612 Make_Integer_Literal (Sloc (Op2),
1615 Analyze_And_Resolve (Op1, Standard_Integer);
1616 Analyze_And_Resolve (Op2, Standard_Integer);
1620 -- Cases where we cannot make runtime call
1622 -- For (a <= b) we convert to not (a > b)
1624 if Chars (N) = Name_Op_Le then
1630 Right_Opnd => Op2)));
1631 Analyze_And_Resolve (N, Standard_Boolean);
1634 -- For < the Boolean expression is
1635 -- greater__nn (op2, op1)
1637 elsif Chars (N) = Name_Op_Lt then
1638 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1642 Op1 := Right_Opnd (N);
1643 Op2 := Left_Opnd (N);
1645 -- For (a >= b) we convert to not (a < b)
1647 elsif Chars (N) = Name_Op_Ge then
1653 Right_Opnd => Op2)));
1654 Analyze_And_Resolve (N, Standard_Boolean);
1657 -- For > the Boolean expression is
1658 -- greater__nn (op1, op2)
1661 pragma Assert (Chars (N) = Name_Op_Gt);
1662 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1665 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1667 Make_Function_Call (Loc,
1668 Name => New_Occurrence_Of (Func_Name, Loc),
1669 Parameter_Associations => New_List (Op1, Op2));
1671 Insert_Action (N, Func_Body);
1673 Analyze_And_Resolve (N, Standard_Boolean);
1676 when RE_Not_Available =>
1678 end Expand_Array_Comparison;
1680 ---------------------------
1681 -- Expand_Array_Equality --
1682 ---------------------------
1684 -- Expand an equality function for multi-dimensional arrays. Here is an
1685 -- example of such a function for Nb_Dimension = 2
1687 -- function Enn (A : atyp; B : btyp) return boolean is
1689 -- if (A'length (1) = 0 or else A'length (2) = 0)
1691 -- (B'length (1) = 0 or else B'length (2) = 0)
1693 -- return True; -- RM 4.5.2(22)
1696 -- if A'length (1) /= B'length (1)
1698 -- A'length (2) /= B'length (2)
1700 -- return False; -- RM 4.5.2(23)
1704 -- A1 : Index_T1 := A'first (1);
1705 -- B1 : Index_T1 := B'first (1);
1709 -- A2 : Index_T2 := A'first (2);
1710 -- B2 : Index_T2 := B'first (2);
1713 -- if A (A1, A2) /= B (B1, B2) then
1717 -- exit when A2 = A'last (2);
1718 -- A2 := Index_T2'succ (A2);
1719 -- B2 := Index_T2'succ (B2);
1723 -- exit when A1 = A'last (1);
1724 -- A1 := Index_T1'succ (A1);
1725 -- B1 := Index_T1'succ (B1);
1732 -- Note on the formal types used (atyp and btyp). If either of the arrays
1733 -- is of a private type, we use the underlying type, and do an unchecked
1734 -- conversion of the actual. If either of the arrays has a bound depending
1735 -- on a discriminant, then we use the base type since otherwise we have an
1736 -- escaped discriminant in the function.
1738 -- If both arrays are constrained and have the same bounds, we can generate
1739 -- a loop with an explicit iteration scheme using a 'Range attribute over
1742 function Expand_Array_Equality
1747 Typ : Entity_Id) return Node_Id
1749 Loc : constant Source_Ptr := Sloc (Nod);
1750 Decls : constant List_Id := New_List;
1751 Index_List1 : constant List_Id := New_List;
1752 Index_List2 : constant List_Id := New_List;
1756 Func_Name : Entity_Id;
1757 Func_Body : Node_Id;
1759 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
1760 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
1764 -- The parameter types to be used for the formals
1769 Num : Int) return Node_Id;
1770 -- This builds the attribute reference Arr'Nam (Expr)
1772 function Component_Equality (Typ : Entity_Id) return Node_Id;
1773 -- Create one statement to compare corresponding components, designated
1774 -- by a full set of indexes.
1776 function Get_Arg_Type (N : Node_Id) return Entity_Id;
1777 -- Given one of the arguments, computes the appropriate type to be used
1778 -- for that argument in the corresponding function formal
1780 function Handle_One_Dimension
1782 Index : Node_Id) return Node_Id;
1783 -- This procedure returns the following code
1786 -- Bn : Index_T := B'First (N);
1790 -- exit when An = A'Last (N);
1791 -- An := Index_T'Succ (An)
1792 -- Bn := Index_T'Succ (Bn)
1796 -- If both indexes are constrained and identical, the procedure
1797 -- returns a simpler loop:
1799 -- for An in A'Range (N) loop
1803 -- N is the dimension for which we are generating a loop. Index is the
1804 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1805 -- xxx statement is either the loop or declare for the next dimension
1806 -- or if this is the last dimension the comparison of corresponding
1807 -- components of the arrays.
1809 -- The actual way the code works is to return the comparison of
1810 -- corresponding components for the N+1 call. That's neater.
1812 function Test_Empty_Arrays return Node_Id;
1813 -- This function constructs the test for both arrays being empty
1814 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1816 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1818 function Test_Lengths_Correspond return Node_Id;
1819 -- This function constructs the test for arrays having different lengths
1820 -- in at least one index position, in which case the resulting code is:
1822 -- A'length (1) /= B'length (1)
1824 -- A'length (2) /= B'length (2)
1835 Num : Int) return Node_Id
1839 Make_Attribute_Reference (Loc,
1840 Attribute_Name => Nam,
1841 Prefix => New_Occurrence_Of (Arr, Loc),
1842 Expressions => New_List (Make_Integer_Literal (Loc, Num)));
1845 ------------------------
1846 -- Component_Equality --
1847 ------------------------
1849 function Component_Equality (Typ : Entity_Id) return Node_Id is
1854 -- if a(i1...) /= b(j1...) then return false; end if;
1857 Make_Indexed_Component (Loc,
1858 Prefix => Make_Identifier (Loc, Chars (A)),
1859 Expressions => Index_List1);
1862 Make_Indexed_Component (Loc,
1863 Prefix => Make_Identifier (Loc, Chars (B)),
1864 Expressions => Index_List2);
1866 Test := Expand_Composite_Equality
1867 (Nod, Component_Type (Typ), L, R, Decls);
1869 -- If some (sub)component is an unchecked_union, the whole operation
1870 -- will raise program error.
1872 if Nkind (Test) = N_Raise_Program_Error then
1874 -- This node is going to be inserted at a location where a
1875 -- statement is expected: clear its Etype so analysis will set
1876 -- it to the expected Standard_Void_Type.
1878 Set_Etype (Test, Empty);
1883 Make_Implicit_If_Statement (Nod,
1884 Condition => Make_Op_Not (Loc, Right_Opnd => Test),
1885 Then_Statements => New_List (
1886 Make_Simple_Return_Statement (Loc,
1887 Expression => New_Occurrence_Of (Standard_False, Loc))));
1889 end Component_Equality;
1895 function Get_Arg_Type (N : Node_Id) return Entity_Id is
1906 T := Underlying_Type (T);
1908 X := First_Index (T);
1909 while Present (X) loop
1910 if Denotes_Discriminant (Type_Low_Bound (Etype (X)))
1912 Denotes_Discriminant (Type_High_Bound (Etype (X)))
1925 --------------------------
1926 -- Handle_One_Dimension --
1927 ---------------------------
1929 function Handle_One_Dimension
1931 Index : Node_Id) return Node_Id
1933 Need_Separate_Indexes : constant Boolean :=
1934 Ltyp /= Rtyp or else not Is_Constrained (Ltyp);
1935 -- If the index types are identical, and we are working with
1936 -- constrained types, then we can use the same index for both
1939 An : constant Entity_Id := Make_Temporary (Loc, 'A');
1942 Index_T : Entity_Id;
1947 if N > Number_Dimensions (Ltyp) then
1948 return Component_Equality (Ltyp);
1951 -- Case where we generate a loop
1953 Index_T := Base_Type (Etype (Index));
1955 if Need_Separate_Indexes then
1956 Bn := Make_Temporary (Loc, 'B');
1961 Append (New_Occurrence_Of (An, Loc), Index_List1);
1962 Append (New_Occurrence_Of (Bn, Loc), Index_List2);
1964 Stm_List := New_List (
1965 Handle_One_Dimension (N + 1, Next_Index (Index)));
1967 if Need_Separate_Indexes then
1969 -- Generate guard for loop, followed by increments of indexes
1971 Append_To (Stm_List,
1972 Make_Exit_Statement (Loc,
1975 Left_Opnd => New_Occurrence_Of (An, Loc),
1976 Right_Opnd => Arr_Attr (A, Name_Last, N))));
1978 Append_To (Stm_List,
1979 Make_Assignment_Statement (Loc,
1980 Name => New_Occurrence_Of (An, Loc),
1982 Make_Attribute_Reference (Loc,
1983 Prefix => New_Occurrence_Of (Index_T, Loc),
1984 Attribute_Name => Name_Succ,
1985 Expressions => New_List (
1986 New_Occurrence_Of (An, Loc)))));
1988 Append_To (Stm_List,
1989 Make_Assignment_Statement (Loc,
1990 Name => New_Occurrence_Of (Bn, Loc),
1992 Make_Attribute_Reference (Loc,
1993 Prefix => New_Occurrence_Of (Index_T, Loc),
1994 Attribute_Name => Name_Succ,
1995 Expressions => New_List (
1996 New_Occurrence_Of (Bn, Loc)))));
1999 -- If separate indexes, we need a declare block for An and Bn, and a
2000 -- loop without an iteration scheme.
2002 if Need_Separate_Indexes then
2004 Make_Implicit_Loop_Statement (Nod, Statements => Stm_List);
2007 Make_Block_Statement (Loc,
2008 Declarations => New_List (
2009 Make_Object_Declaration (Loc,
2010 Defining_Identifier => An,
2011 Object_Definition => New_Occurrence_Of (Index_T, Loc),
2012 Expression => Arr_Attr (A, Name_First, N)),
2014 Make_Object_Declaration (Loc,
2015 Defining_Identifier => Bn,
2016 Object_Definition => New_Occurrence_Of (Index_T, Loc),
2017 Expression => Arr_Attr (B, Name_First, N))),
2019 Handled_Statement_Sequence =>
2020 Make_Handled_Sequence_Of_Statements (Loc,
2021 Statements => New_List (Loop_Stm)));
2023 -- If no separate indexes, return loop statement with explicit
2024 -- iteration scheme on its own
2028 Make_Implicit_Loop_Statement (Nod,
2029 Statements => Stm_List,
2031 Make_Iteration_Scheme (Loc,
2032 Loop_Parameter_Specification =>
2033 Make_Loop_Parameter_Specification (Loc,
2034 Defining_Identifier => An,
2035 Discrete_Subtype_Definition =>
2036 Arr_Attr (A, Name_Range, N))));
2039 end Handle_One_Dimension;
2041 -----------------------
2042 -- Test_Empty_Arrays --
2043 -----------------------
2045 function Test_Empty_Arrays return Node_Id is
2055 for J in 1 .. Number_Dimensions (Ltyp) loop
2058 Left_Opnd => Arr_Attr (A, Name_Length, J),
2059 Right_Opnd => Make_Integer_Literal (Loc, 0));
2063 Left_Opnd => Arr_Attr (B, Name_Length, J),
2064 Right_Opnd => Make_Integer_Literal (Loc, 0));
2073 Left_Opnd => Relocate_Node (Alist),
2074 Right_Opnd => Atest);
2078 Left_Opnd => Relocate_Node (Blist),
2079 Right_Opnd => Btest);
2086 Right_Opnd => Blist);
2087 end Test_Empty_Arrays;
2089 -----------------------------
2090 -- Test_Lengths_Correspond --
2091 -----------------------------
2093 function Test_Lengths_Correspond return Node_Id is
2099 for J in 1 .. Number_Dimensions (Ltyp) loop
2102 Left_Opnd => Arr_Attr (A, Name_Length, J),
2103 Right_Opnd => Arr_Attr (B, Name_Length, J));
2110 Left_Opnd => Relocate_Node (Result),
2111 Right_Opnd => Rtest);
2116 end Test_Lengths_Correspond;
2118 -- Start of processing for Expand_Array_Equality
2121 Ltyp := Get_Arg_Type (Lhs);
2122 Rtyp := Get_Arg_Type (Rhs);
2124 -- For now, if the argument types are not the same, go to the base type,
2125 -- since the code assumes that the formals have the same type. This is
2126 -- fixable in future ???
2128 if Ltyp /= Rtyp then
2129 Ltyp := Base_Type (Ltyp);
2130 Rtyp := Base_Type (Rtyp);
2131 pragma Assert (Ltyp = Rtyp);
2134 -- Build list of formals for function
2136 Formals := New_List (
2137 Make_Parameter_Specification (Loc,
2138 Defining_Identifier => A,
2139 Parameter_Type => New_Occurrence_Of (Ltyp, Loc)),
2141 Make_Parameter_Specification (Loc,
2142 Defining_Identifier => B,
2143 Parameter_Type => New_Occurrence_Of (Rtyp, Loc)));
2145 Func_Name := Make_Temporary (Loc, 'E');
2147 -- Build statement sequence for function
2150 Make_Subprogram_Body (Loc,
2152 Make_Function_Specification (Loc,
2153 Defining_Unit_Name => Func_Name,
2154 Parameter_Specifications => Formals,
2155 Result_Definition => New_Occurrence_Of (Standard_Boolean, Loc)),
2157 Declarations => Decls,
2159 Handled_Statement_Sequence =>
2160 Make_Handled_Sequence_Of_Statements (Loc,
2161 Statements => New_List (
2163 Make_Implicit_If_Statement (Nod,
2164 Condition => Test_Empty_Arrays,
2165 Then_Statements => New_List (
2166 Make_Simple_Return_Statement (Loc,
2168 New_Occurrence_Of (Standard_True, Loc)))),
2170 Make_Implicit_If_Statement (Nod,
2171 Condition => Test_Lengths_Correspond,
2172 Then_Statements => New_List (
2173 Make_Simple_Return_Statement (Loc,
2174 Expression => New_Occurrence_Of (Standard_False, Loc)))),
2176 Handle_One_Dimension (1, First_Index (Ltyp)),
2178 Make_Simple_Return_Statement (Loc,
2179 Expression => New_Occurrence_Of (Standard_True, Loc)))));
2181 Set_Has_Completion (Func_Name, True);
2182 Set_Is_Inlined (Func_Name);
2184 -- If the array type is distinct from the type of the arguments, it
2185 -- is the full view of a private type. Apply an unchecked conversion
2186 -- to insure that analysis of the call succeeds.
2196 or else Base_Type (Etype (Lhs)) /= Base_Type (Ltyp)
2198 L := OK_Convert_To (Ltyp, Lhs);
2202 or else Base_Type (Etype (Rhs)) /= Base_Type (Rtyp)
2204 R := OK_Convert_To (Rtyp, Rhs);
2207 Actuals := New_List (L, R);
2210 Append_To (Bodies, Func_Body);
2213 Make_Function_Call (Loc,
2214 Name => New_Occurrence_Of (Func_Name, Loc),
2215 Parameter_Associations => Actuals);
2216 end Expand_Array_Equality;
2218 -----------------------------
2219 -- Expand_Boolean_Operator --
2220 -----------------------------
2222 -- Note that we first get the actual subtypes of the operands, since we
2223 -- always want to deal with types that have bounds.
2225 procedure Expand_Boolean_Operator (N : Node_Id) is
2226 Typ : constant Entity_Id := Etype (N);
2229 -- Special case of bit packed array where both operands are known to be
2230 -- properly aligned. In this case we use an efficient run time routine
2231 -- to carry out the operation (see System.Bit_Ops).
2233 if Is_Bit_Packed_Array (Typ)
2234 and then not Is_Possibly_Unaligned_Object (Left_Opnd (N))
2235 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
2237 Expand_Packed_Boolean_Operator (N);
2241 -- For the normal non-packed case, the general expansion is to build
2242 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
2243 -- and then inserting it into the tree. The original operator node is
2244 -- then rewritten as a call to this function. We also use this in the
2245 -- packed case if either operand is a possibly unaligned object.
2248 Loc : constant Source_Ptr := Sloc (N);
2249 L : constant Node_Id := Relocate_Node (Left_Opnd (N));
2250 R : constant Node_Id := Relocate_Node (Right_Opnd (N));
2251 Func_Body : Node_Id;
2252 Func_Name : Entity_Id;
2255 Convert_To_Actual_Subtype (L);
2256 Convert_To_Actual_Subtype (R);
2257 Ensure_Defined (Etype (L), N);
2258 Ensure_Defined (Etype (R), N);
2259 Apply_Length_Check (R, Etype (L));
2261 if Nkind (N) = N_Op_Xor then
2262 Silly_Boolean_Array_Xor_Test (N, Etype (L));
2265 if Nkind (Parent (N)) = N_Assignment_Statement
2266 and then Safe_In_Place_Array_Op (Name (Parent (N)), L, R)
2268 Build_Boolean_Array_Proc_Call (Parent (N), L, R);
2270 elsif Nkind (Parent (N)) = N_Op_Not
2271 and then Nkind (N) = N_Op_And
2272 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
2273 and then Safe_In_Place_Array_Op (Name (Parent (Parent (N))), L, R)
2278 Func_Body := Make_Boolean_Array_Op (Etype (L), N);
2279 Func_Name := Defining_Unit_Name (Specification (Func_Body));
2280 Insert_Action (N, Func_Body);
2282 -- Now rewrite the expression with a call
2285 Make_Function_Call (Loc,
2286 Name => New_Occurrence_Of (Func_Name, Loc),
2287 Parameter_Associations =>
2290 Make_Type_Conversion
2291 (Loc, New_Occurrence_Of (Etype (L), Loc), R))));
2293 Analyze_And_Resolve (N, Typ);
2296 end Expand_Boolean_Operator;
2298 ------------------------------------------------
2299 -- Expand_Compare_Minimize_Eliminate_Overflow --
2300 ------------------------------------------------
2302 procedure Expand_Compare_Minimize_Eliminate_Overflow (N : Node_Id) is
2303 Loc : constant Source_Ptr := Sloc (N);
2305 Result_Type : constant Entity_Id := Etype (N);
2306 -- Capture result type (could be a derived boolean type)
2311 LLIB : constant Entity_Id := Base_Type (Standard_Long_Long_Integer);
2312 -- Entity for Long_Long_Integer'Base
2314 Check : constant Overflow_Mode_Type := Overflow_Check_Mode;
2315 -- Current overflow checking mode
2318 procedure Set_False;
2319 -- These procedures rewrite N with an occurrence of Standard_True or
2320 -- Standard_False, and then makes a call to Warn_On_Known_Condition.
2326 procedure Set_False is
2328 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
2329 Warn_On_Known_Condition (N);
2336 procedure Set_True is
2338 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
2339 Warn_On_Known_Condition (N);
2342 -- Start of processing for Expand_Compare_Minimize_Eliminate_Overflow
2345 -- Nothing to do unless we have a comparison operator with operands
2346 -- that are signed integer types, and we are operating in either
2347 -- MINIMIZED or ELIMINATED overflow checking mode.
2349 if Nkind (N) not in N_Op_Compare
2350 or else Check not in Minimized_Or_Eliminated
2351 or else not Is_Signed_Integer_Type (Etype (Left_Opnd (N)))
2356 -- OK, this is the case we are interested in. First step is to process
2357 -- our operands using the Minimize_Eliminate circuitry which applies
2358 -- this processing to the two operand subtrees.
2360 Minimize_Eliminate_Overflows
2361 (Left_Opnd (N), Llo, Lhi, Top_Level => False);
2362 Minimize_Eliminate_Overflows
2363 (Right_Opnd (N), Rlo, Rhi, Top_Level => False);
2365 -- See if the range information decides the result of the comparison.
2366 -- We can only do this if we in fact have full range information (which
2367 -- won't be the case if either operand is bignum at this stage).
2369 if Llo /= No_Uint and then Rlo /= No_Uint then
2370 case N_Op_Compare (Nkind (N)) is
2372 if Llo = Lhi and then Rlo = Rhi and then Llo = Rlo then
2374 elsif Llo > Rhi or else Lhi < Rlo then
2381 elsif Lhi < Rlo then
2388 elsif Lhi <= Rlo then
2395 elsif Lhi <= Rlo then
2402 elsif Lhi < Rlo then
2407 if Llo = Lhi and then Rlo = Rhi and then Llo = Rlo then
2409 elsif Llo > Rhi or else Lhi < Rlo then
2414 -- All done if we did the rewrite
2416 if Nkind (N) not in N_Op_Compare then
2421 -- Otherwise, time to do the comparison
2424 Ltype : constant Entity_Id := Etype (Left_Opnd (N));
2425 Rtype : constant Entity_Id := Etype (Right_Opnd (N));
2428 -- If the two operands have the same signed integer type we are
2429 -- all set, nothing more to do. This is the case where either
2430 -- both operands were unchanged, or we rewrote both of them to
2431 -- be Long_Long_Integer.
2433 -- Note: Entity for the comparison may be wrong, but it's not worth
2434 -- the effort to change it, since the back end does not use it.
2436 if Is_Signed_Integer_Type (Ltype)
2437 and then Base_Type (Ltype) = Base_Type (Rtype)
2441 -- Here if bignums are involved (can only happen in ELIMINATED mode)
2443 elsif Is_RTE (Ltype, RE_Bignum) or else Is_RTE (Rtype, RE_Bignum) then
2445 Left : Node_Id := Left_Opnd (N);
2446 Right : Node_Id := Right_Opnd (N);
2447 -- Bignum references for left and right operands
2450 if not Is_RTE (Ltype, RE_Bignum) then
2451 Left := Convert_To_Bignum (Left);
2452 elsif not Is_RTE (Rtype, RE_Bignum) then
2453 Right := Convert_To_Bignum (Right);
2456 -- We rewrite our node with:
2459 -- Bnn : Result_Type;
2461 -- M : Mark_Id := SS_Mark;
2463 -- Bnn := Big_xx (Left, Right); (xx = EQ, NT etc)
2471 Blk : constant Node_Id := Make_Bignum_Block (Loc);
2472 Bnn : constant Entity_Id := Make_Temporary (Loc, 'B', N);
2476 case N_Op_Compare (Nkind (N)) is
2477 when N_Op_Eq => Ent := RE_Big_EQ;
2478 when N_Op_Ge => Ent := RE_Big_GE;
2479 when N_Op_Gt => Ent := RE_Big_GT;
2480 when N_Op_Le => Ent := RE_Big_LE;
2481 when N_Op_Lt => Ent := RE_Big_LT;
2482 when N_Op_Ne => Ent := RE_Big_NE;
2485 -- Insert assignment to Bnn into the bignum block
2488 (First (Statements (Handled_Statement_Sequence (Blk))),
2489 Make_Assignment_Statement (Loc,
2490 Name => New_Occurrence_Of (Bnn, Loc),
2492 Make_Function_Call (Loc,
2494 New_Occurrence_Of (RTE (Ent), Loc),
2495 Parameter_Associations => New_List (Left, Right))));
2497 -- Now do the rewrite with expression actions
2500 Make_Expression_With_Actions (Loc,
2501 Actions => New_List (
2502 Make_Object_Declaration (Loc,
2503 Defining_Identifier => Bnn,
2504 Object_Definition =>
2505 New_Occurrence_Of (Result_Type, Loc)),
2507 Expression => New_Occurrence_Of (Bnn, Loc)));
2508 Analyze_And_Resolve (N, Result_Type);
2512 -- No bignums involved, but types are different, so we must have
2513 -- rewritten one of the operands as a Long_Long_Integer but not
2516 -- If left operand is Long_Long_Integer, convert right operand
2517 -- and we are done (with a comparison of two Long_Long_Integers).
2519 elsif Ltype = LLIB then
2520 Convert_To_And_Rewrite (LLIB, Right_Opnd (N));
2521 Analyze_And_Resolve (Right_Opnd (N), LLIB, Suppress => All_Checks);
2524 -- If right operand is Long_Long_Integer, convert left operand
2525 -- and we are done (with a comparison of two Long_Long_Integers).
2527 -- This is the only remaining possibility
2529 else pragma Assert (Rtype = LLIB);
2530 Convert_To_And_Rewrite (LLIB, Left_Opnd (N));
2531 Analyze_And_Resolve (Left_Opnd (N), LLIB, Suppress => All_Checks);
2535 end Expand_Compare_Minimize_Eliminate_Overflow;
2537 -------------------------------
2538 -- Expand_Composite_Equality --
2539 -------------------------------
2541 -- This function is only called for comparing internal fields of composite
2542 -- types when these fields are themselves composites. This is a special
2543 -- case because it is not possible to respect normal Ada visibility rules.
2545 function Expand_Composite_Equality
2550 Bodies : List_Id) return Node_Id
2552 Loc : constant Source_Ptr := Sloc (Nod);
2553 Full_Type : Entity_Id;
2557 function Find_Primitive_Eq return Node_Id;
2558 -- AI05-0123: Locate primitive equality for type if it exists, and
2559 -- build the corresponding call. If operation is abstract, replace
2560 -- call with an explicit raise. Return Empty if there is no primitive.
2562 -----------------------
2563 -- Find_Primitive_Eq --
2564 -----------------------
2566 function Find_Primitive_Eq return Node_Id is
2571 Prim_E := First_Elmt (Collect_Primitive_Operations (Typ));
2572 while Present (Prim_E) loop
2573 Prim := Node (Prim_E);
2575 -- Locate primitive equality with the right signature
2577 if Chars (Prim) = Name_Op_Eq
2578 and then Etype (First_Formal (Prim)) =
2579 Etype (Next_Formal (First_Formal (Prim)))
2580 and then Etype (Prim) = Standard_Boolean
2582 if Is_Abstract_Subprogram (Prim) then
2584 Make_Raise_Program_Error (Loc,
2585 Reason => PE_Explicit_Raise);
2589 Make_Function_Call (Loc,
2590 Name => New_Occurrence_Of (Prim, Loc),
2591 Parameter_Associations => New_List (Lhs, Rhs));
2598 -- If not found, predefined operation will be used
2601 end Find_Primitive_Eq;
2603 -- Start of processing for Expand_Composite_Equality
2606 if Is_Private_Type (Typ) then
2607 Full_Type := Underlying_Type (Typ);
2612 -- If the private type has no completion the context may be the
2613 -- expansion of a composite equality for a composite type with some
2614 -- still incomplete components. The expression will not be analyzed
2615 -- until the enclosing type is completed, at which point this will be
2616 -- properly expanded, unless there is a bona fide completion error.
2618 if No (Full_Type) then
2619 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2622 Full_Type := Base_Type (Full_Type);
2624 -- When the base type itself is private, use the full view to expand
2625 -- the composite equality.
2627 if Is_Private_Type (Full_Type) then
2628 Full_Type := Underlying_Type (Full_Type);
2631 -- Case of array types
2633 if Is_Array_Type (Full_Type) then
2635 -- If the operand is an elementary type other than a floating-point
2636 -- type, then we can simply use the built-in block bitwise equality,
2637 -- since the predefined equality operators always apply and bitwise
2638 -- equality is fine for all these cases.
2640 if Is_Elementary_Type (Component_Type (Full_Type))
2641 and then not Is_Floating_Point_Type (Component_Type (Full_Type))
2643 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2645 -- For composite component types, and floating-point types, use the
2646 -- expansion. This deals with tagged component types (where we use
2647 -- the applicable equality routine) and floating-point, (where we
2648 -- need to worry about negative zeroes), and also the case of any
2649 -- composite type recursively containing such fields.
2652 return Expand_Array_Equality (Nod, Lhs, Rhs, Bodies, Full_Type);
2655 -- Case of tagged record types
2657 elsif Is_Tagged_Type (Full_Type) then
2659 -- Call the primitive operation "=" of this type
2661 if Is_Class_Wide_Type (Full_Type) then
2662 Full_Type := Root_Type (Full_Type);
2665 -- If this is derived from an untagged private type completed with a
2666 -- tagged type, it does not have a full view, so we use the primitive
2667 -- operations of the private type. This check should no longer be
2668 -- necessary when these types receive their full views ???
2670 if Is_Private_Type (Typ)
2671 and then not Is_Tagged_Type (Typ)
2672 and then not Is_Controlled (Typ)
2673 and then Is_Derived_Type (Typ)
2674 and then No (Full_View (Typ))
2676 Prim := First_Elmt (Collect_Primitive_Operations (Typ));
2678 Prim := First_Elmt (Primitive_Operations (Full_Type));
2682 Eq_Op := Node (Prim);
2683 exit when Chars (Eq_Op) = Name_Op_Eq
2684 and then Etype (First_Formal (Eq_Op)) =
2685 Etype (Next_Formal (First_Formal (Eq_Op)))
2686 and then Base_Type (Etype (Eq_Op)) = Standard_Boolean;
2688 pragma Assert (Present (Prim));
2691 Eq_Op := Node (Prim);
2694 Make_Function_Call (Loc,
2695 Name => New_Occurrence_Of (Eq_Op, Loc),
2696 Parameter_Associations =>
2698 (Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Lhs),
2699 Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Rhs)));
2701 -- Case of untagged record types
2703 elsif Is_Record_Type (Full_Type) then
2704 Eq_Op := TSS (Full_Type, TSS_Composite_Equality);
2706 if Present (Eq_Op) then
2707 if Etype (First_Formal (Eq_Op)) /= Full_Type then
2709 -- Inherited equality from parent type. Convert the actuals to
2710 -- match signature of operation.
2713 T : constant Entity_Id := Etype (First_Formal (Eq_Op));
2717 Make_Function_Call (Loc,
2718 Name => New_Occurrence_Of (Eq_Op, Loc),
2719 Parameter_Associations => New_List (
2720 OK_Convert_To (T, Lhs),
2721 OK_Convert_To (T, Rhs)));
2725 -- Comparison between Unchecked_Union components
2727 if Is_Unchecked_Union (Full_Type) then
2729 Lhs_Type : Node_Id := Full_Type;
2730 Rhs_Type : Node_Id := Full_Type;
2731 Lhs_Discr_Val : Node_Id;
2732 Rhs_Discr_Val : Node_Id;
2737 if Nkind (Lhs) = N_Selected_Component then
2738 Lhs_Type := Etype (Entity (Selector_Name (Lhs)));
2743 if Nkind (Rhs) = N_Selected_Component then
2744 Rhs_Type := Etype (Entity (Selector_Name (Rhs)));
2747 -- Lhs of the composite equality
2749 if Is_Constrained (Lhs_Type) then
2751 -- Since the enclosing record type can never be an
2752 -- Unchecked_Union (this code is executed for records
2753 -- that do not have variants), we may reference its
2756 if Nkind (Lhs) = N_Selected_Component
2757 and then Has_Per_Object_Constraint
2758 (Entity (Selector_Name (Lhs)))
2761 Make_Selected_Component (Loc,
2762 Prefix => Prefix (Lhs),
2765 (Get_Discriminant_Value
2766 (First_Discriminant (Lhs_Type),
2768 Stored_Constraint (Lhs_Type))));
2773 (Get_Discriminant_Value
2774 (First_Discriminant (Lhs_Type),
2776 Stored_Constraint (Lhs_Type)));
2780 -- It is not possible to infer the discriminant since
2781 -- the subtype is not constrained.
2784 Make_Raise_Program_Error (Loc,
2785 Reason => PE_Unchecked_Union_Restriction);
2788 -- Rhs of the composite equality
2790 if Is_Constrained (Rhs_Type) then
2791 if Nkind (Rhs) = N_Selected_Component
2792 and then Has_Per_Object_Constraint
2793 (Entity (Selector_Name (Rhs)))
2796 Make_Selected_Component (Loc,
2797 Prefix => Prefix (Rhs),
2800 (Get_Discriminant_Value
2801 (First_Discriminant (Rhs_Type),
2803 Stored_Constraint (Rhs_Type))));
2808 (Get_Discriminant_Value
2809 (First_Discriminant (Rhs_Type),
2811 Stored_Constraint (Rhs_Type)));
2816 Make_Raise_Program_Error (Loc,
2817 Reason => PE_Unchecked_Union_Restriction);
2820 -- Call the TSS equality function with the inferred
2821 -- discriminant values.
2824 Make_Function_Call (Loc,
2825 Name => New_Occurrence_Of (Eq_Op, Loc),
2826 Parameter_Associations => New_List (
2833 -- All cases other than comparing Unchecked_Union types
2837 T : constant Entity_Id := Etype (First_Formal (Eq_Op));
2840 Make_Function_Call (Loc,
2842 New_Occurrence_Of (Eq_Op, Loc),
2843 Parameter_Associations => New_List (
2844 OK_Convert_To (T, Lhs),
2845 OK_Convert_To (T, Rhs)));
2850 -- Equality composes in Ada 2012 for untagged record types. It also
2851 -- composes for bounded strings, because they are part of the
2852 -- predefined environment. We could make it compose for bounded
2853 -- strings by making them tagged, or by making sure all subcomponents
2854 -- are set to the same value, even when not used. Instead, we have
2855 -- this special case in the compiler, because it's more efficient.
2857 elsif Ada_Version >= Ada_2012 or else Is_Bounded_String (Typ) then
2859 -- If no TSS has been created for the type, check whether there is
2860 -- a primitive equality declared for it.
2863 Op : constant Node_Id := Find_Primitive_Eq;
2866 -- Use user-defined primitive if it exists, otherwise use
2867 -- predefined equality.
2869 if Present (Op) then
2872 return Make_Op_Eq (Loc, Lhs, Rhs);
2877 return Expand_Record_Equality (Nod, Full_Type, Lhs, Rhs, Bodies);
2880 -- Non-composite types (always use predefined equality)
2883 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2885 end Expand_Composite_Equality;
2887 ------------------------
2888 -- Expand_Concatenate --
2889 ------------------------
2891 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id) is
2892 Loc : constant Source_Ptr := Sloc (Cnode);
2894 Atyp : constant Entity_Id := Base_Type (Etype (Cnode));
2895 -- Result type of concatenation
2897 Ctyp : constant Entity_Id := Base_Type (Component_Type (Etype (Cnode)));
2898 -- Component type. Elements of this component type can appear as one
2899 -- of the operands of concatenation as well as arrays.
2901 Istyp : constant Entity_Id := Etype (First_Index (Atyp));
2904 Ityp : constant Entity_Id := Base_Type (Istyp);
2905 -- Index type. This is the base type of the index subtype, and is used
2906 -- for all computed bounds (which may be out of range of Istyp in the
2907 -- case of null ranges).
2910 -- This is the type we use to do arithmetic to compute the bounds and
2911 -- lengths of operands. The choice of this type is a little subtle and
2912 -- is discussed in a separate section at the start of the body code.
2914 Concatenation_Error : exception;
2915 -- Raised if concatenation is sure to raise a CE
2917 Result_May_Be_Null : Boolean := True;
2918 -- Reset to False if at least one operand is encountered which is known
2919 -- at compile time to be non-null. Used for handling the special case
2920 -- of setting the high bound to the last operand high bound for a null
2921 -- result, thus ensuring a proper high bound in the super-flat case.
2923 N : constant Nat := List_Length (Opnds);
2924 -- Number of concatenation operands including possibly null operands
2927 -- Number of operands excluding any known to be null, except that the
2928 -- last operand is always retained, in case it provides the bounds for
2932 -- Current operand being processed in the loop through operands. After
2933 -- this loop is complete, always contains the last operand (which is not
2934 -- the same as Operands (NN), since null operands are skipped).
2936 -- Arrays describing the operands, only the first NN entries of each
2937 -- array are set (NN < N when we exclude known null operands).
2939 Is_Fixed_Length : array (1 .. N) of Boolean;
2940 -- True if length of corresponding operand known at compile time
2942 Operands : array (1 .. N) of Node_Id;
2943 -- Set to the corresponding entry in the Opnds list (but note that null
2944 -- operands are excluded, so not all entries in the list are stored).
2946 Fixed_Length : array (1 .. N) of Uint;
2947 -- Set to length of operand. Entries in this array are set only if the
2948 -- corresponding entry in Is_Fixed_Length is True.
2950 Opnd_Low_Bound : array (1 .. N) of Node_Id;
2951 -- Set to lower bound of operand. Either an integer literal in the case
2952 -- where the bound is known at compile time, else actual lower bound.
2953 -- The operand low bound is of type Ityp.
2955 Var_Length : array (1 .. N) of Entity_Id;
2956 -- Set to an entity of type Natural that contains the length of an
2957 -- operand whose length is not known at compile time. Entries in this
2958 -- array are set only if the corresponding entry in Is_Fixed_Length
2959 -- is False. The entity is of type Artyp.
2961 Aggr_Length : array (0 .. N) of Node_Id;
2962 -- The J'th entry in an expression node that represents the total length
2963 -- of operands 1 through J. It is either an integer literal node, or a
2964 -- reference to a constant entity with the right value, so it is fine
2965 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2966 -- entry always is set to zero. The length is of type Artyp.
2968 Low_Bound : Node_Id;
2969 -- A tree node representing the low bound of the result (of type Ityp).
2970 -- This is either an integer literal node, or an identifier reference to
2971 -- a constant entity initialized to the appropriate value.
2973 Last_Opnd_Low_Bound : Node_Id;
2974 -- A tree node representing the low bound of the last operand. This
2975 -- need only be set if the result could be null. It is used for the
2976 -- special case of setting the right low bound for a null result.
2977 -- This is of type Ityp.
2979 Last_Opnd_High_Bound : Node_Id;
2980 -- A tree node representing the high bound of the last operand. This
2981 -- need only be set if the result could be null. It is used for the
2982 -- special case of setting the right high bound for a null result.
2983 -- This is of type Ityp.
2985 High_Bound : Node_Id;
2986 -- A tree node representing the high bound of the result (of type Ityp)
2989 -- Result of the concatenation (of type Ityp)
2991 Actions : constant List_Id := New_List;
2992 -- Collect actions to be inserted
2994 Known_Non_Null_Operand_Seen : Boolean;
2995 -- Set True during generation of the assignments of operands into
2996 -- result once an operand known to be non-null has been seen.
2998 function Make_Artyp_Literal (Val : Nat) return Node_Id;
2999 -- This function makes an N_Integer_Literal node that is returned in
3000 -- analyzed form with the type set to Artyp. Importantly this literal
3001 -- is not flagged as static, so that if we do computations with it that
3002 -- result in statically detected out of range conditions, we will not
3003 -- generate error messages but instead warning messages.
3005 function To_Artyp (X : Node_Id) return Node_Id;
3006 -- Given a node of type Ityp, returns the corresponding value of type
3007 -- Artyp. For non-enumeration types, this is a plain integer conversion.
3008 -- For enum types, the Pos of the value is returned.
3010 function To_Ityp (X : Node_Id) return Node_Id;
3011 -- The inverse function (uses Val in the case of enumeration types)
3013 ------------------------
3014 -- Make_Artyp_Literal --
3015 ------------------------
3017 function Make_Artyp_Literal (Val : Nat) return Node_Id is
3018 Result : constant Node_Id := Make_Integer_Literal (Loc, Val);
3020 Set_Etype (Result, Artyp);
3021 Set_Analyzed (Result, True);
3022 Set_Is_Static_Expression (Result, False);
3024 end Make_Artyp_Literal;
3030 function To_Artyp (X : Node_Id) return Node_Id is
3032 if Ityp = Base_Type (Artyp) then
3035 elsif Is_Enumeration_Type (Ityp) then
3037 Make_Attribute_Reference (Loc,
3038 Prefix => New_Occurrence_Of (Ityp, Loc),
3039 Attribute_Name => Name_Pos,
3040 Expressions => New_List (X));
3043 return Convert_To (Artyp, X);
3051 function To_Ityp (X : Node_Id) return Node_Id is
3053 if Is_Enumeration_Type (Ityp) then
3055 Make_Attribute_Reference (Loc,
3056 Prefix => New_Occurrence_Of (Ityp, Loc),
3057 Attribute_Name => Name_Val,
3058 Expressions => New_List (X));
3060 -- Case where we will do a type conversion
3063 if Ityp = Base_Type (Artyp) then
3066 return Convert_To (Ityp, X);
3071 -- Local Declarations
3073 Lib_Level_Target : constant Boolean :=
3074 Nkind (Parent (Cnode)) = N_Object_Declaration
3076 Is_Library_Level_Entity (Defining_Identifier (Parent (Cnode)));
3078 -- If the concatenation declares a library level entity, we call the
3079 -- built-in concatenation routines to prevent code bloat, regardless
3080 -- of optimization level. This is space-efficient, and prevent linking
3081 -- problems when units are compiled with different optimizations.
3083 Opnd_Typ : Entity_Id;
3090 -- Start of processing for Expand_Concatenate
3093 -- Choose an appropriate computational type
3095 -- We will be doing calculations of lengths and bounds in this routine
3096 -- and computing one from the other in some cases, e.g. getting the high
3097 -- bound by adding the length-1 to the low bound.
3099 -- We can't just use the index type, or even its base type for this
3100 -- purpose for two reasons. First it might be an enumeration type which
3101 -- is not suitable for computations of any kind, and second it may
3102 -- simply not have enough range. For example if the index type is
3103 -- -128..+127 then lengths can be up to 256, which is out of range of
3106 -- For enumeration types, we can simply use Standard_Integer, this is
3107 -- sufficient since the actual number of enumeration literals cannot
3108 -- possibly exceed the range of integer (remember we will be doing the
3109 -- arithmetic with POS values, not representation values).
3111 if Is_Enumeration_Type (Ityp) then
3112 Artyp := Standard_Integer;
3114 -- If index type is Positive, we use the standard unsigned type, to give
3115 -- more room on the top of the range, obviating the need for an overflow
3116 -- check when creating the upper bound. This is needed to avoid junk
3117 -- overflow checks in the common case of String types.
3119 -- ??? Disabled for now
3121 -- elsif Istyp = Standard_Positive then
3122 -- Artyp := Standard_Unsigned;
3124 -- For modular types, we use a 32-bit modular type for types whose size
3125 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
3126 -- identity type, and for larger unsigned types we use 64-bits.
3128 elsif Is_Modular_Integer_Type (Ityp) then
3129 if RM_Size (Ityp) < RM_Size (Standard_Unsigned) then
3130 Artyp := Standard_Unsigned;
3131 elsif RM_Size (Ityp) = RM_Size (Standard_Unsigned) then
3134 Artyp := RTE (RE_Long_Long_Unsigned);
3137 -- Similar treatment for signed types
3140 if RM_Size (Ityp) < RM_Size (Standard_Integer) then
3141 Artyp := Standard_Integer;
3142 elsif RM_Size (Ityp) = RM_Size (Standard_Integer) then
3145 Artyp := Standard_Long_Long_Integer;
3149 -- Supply dummy entry at start of length array
3151 Aggr_Length (0) := Make_Artyp_Literal (0);
3153 -- Go through operands setting up the above arrays
3157 Opnd := Remove_Head (Opnds);
3158 Opnd_Typ := Etype (Opnd);
3160 -- The parent got messed up when we put the operands in a list,
3161 -- so now put back the proper parent for the saved operand, that
3162 -- is to say the concatenation node, to make sure that each operand
3163 -- is seen as a subexpression, e.g. if actions must be inserted.
3165 Set_Parent (Opnd, Cnode);
3167 -- Set will be True when we have setup one entry in the array
3171 -- Singleton element (or character literal) case
3173 if Base_Type (Opnd_Typ) = Ctyp then
3175 Operands (NN) := Opnd;
3176 Is_Fixed_Length (NN) := True;
3177 Fixed_Length (NN) := Uint_1;
3178 Result_May_Be_Null := False;
3180 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
3181 -- since we know that the result cannot be null).
3183 Opnd_Low_Bound (NN) :=
3184 Make_Attribute_Reference (Loc,
3185 Prefix => New_Occurrence_Of (Istyp, Loc),
3186 Attribute_Name => Name_First);
3190 -- String literal case (can only occur for strings of course)
3192 elsif Nkind (Opnd) = N_String_Literal then
3193 Len := String_Literal_Length (Opnd_Typ);
3196 Result_May_Be_Null := False;
3199 -- Capture last operand low and high bound if result could be null
3201 if J = N and then Result_May_Be_Null then
3202 Last_Opnd_Low_Bound :=
3203 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ));
3205 Last_Opnd_High_Bound :=
3206 Make_Op_Subtract (Loc,
3208 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ)),
3209 Right_Opnd => Make_Integer_Literal (Loc, 1));
3212 -- Skip null string literal
3214 if J < N and then Len = 0 then
3219 Operands (NN) := Opnd;
3220 Is_Fixed_Length (NN) := True;
3222 -- Set length and bounds
3224 Fixed_Length (NN) := Len;
3226 Opnd_Low_Bound (NN) :=
3227 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ));
3234 -- Check constrained case with known bounds
3236 if Is_Constrained (Opnd_Typ) then
3238 Index : constant Node_Id := First_Index (Opnd_Typ);
3239 Indx_Typ : constant Entity_Id := Etype (Index);
3240 Lo : constant Node_Id := Type_Low_Bound (Indx_Typ);
3241 Hi : constant Node_Id := Type_High_Bound (Indx_Typ);
3244 -- Fixed length constrained array type with known at compile
3245 -- time bounds is last case of fixed length operand.
3247 if Compile_Time_Known_Value (Lo)
3249 Compile_Time_Known_Value (Hi)
3252 Loval : constant Uint := Expr_Value (Lo);
3253 Hival : constant Uint := Expr_Value (Hi);
3254 Len : constant Uint :=
3255 UI_Max (Hival - Loval + 1, Uint_0);
3259 Result_May_Be_Null := False;
3262 -- Capture last operand bounds if result could be null
3264 if J = N and then Result_May_Be_Null then
3265 Last_Opnd_Low_Bound :=
3267 Make_Integer_Literal (Loc, Expr_Value (Lo)));
3269 Last_Opnd_High_Bound :=
3271 Make_Integer_Literal (Loc, Expr_Value (Hi)));
3274 -- Exclude null length case unless last operand
3276 if J < N and then Len = 0 then
3281 Operands (NN) := Opnd;
3282 Is_Fixed_Length (NN) := True;
3283 Fixed_Length (NN) := Len;
3285 Opnd_Low_Bound (NN) :=
3287 (Make_Integer_Literal (Loc, Expr_Value (Lo)));
3294 -- All cases where the length is not known at compile time, or the
3295 -- special case of an operand which is known to be null but has a
3296 -- lower bound other than 1 or is other than a string type.
3301 -- Capture operand bounds
3303 Opnd_Low_Bound (NN) :=
3304 Make_Attribute_Reference (Loc,
3306 Duplicate_Subexpr (Opnd, Name_Req => True),
3307 Attribute_Name => Name_First);
3309 -- Capture last operand bounds if result could be null
3311 if J = N and Result_May_Be_Null then
3312 Last_Opnd_Low_Bound :=
3314 Make_Attribute_Reference (Loc,
3316 Duplicate_Subexpr (Opnd, Name_Req => True),
3317 Attribute_Name => Name_First));
3319 Last_Opnd_High_Bound :=
3321 Make_Attribute_Reference (Loc,
3323 Duplicate_Subexpr (Opnd, Name_Req => True),
3324 Attribute_Name => Name_Last));
3327 -- Capture length of operand in entity
3329 Operands (NN) := Opnd;
3330 Is_Fixed_Length (NN) := False;
3332 Var_Length (NN) := Make_Temporary (Loc, 'L');
3335 Make_Object_Declaration (Loc,
3336 Defining_Identifier => Var_Length (NN),
3337 Constant_Present => True,
3338 Object_Definition => New_Occurrence_Of (Artyp, Loc),
3340 Make_Attribute_Reference (Loc,
3342 Duplicate_Subexpr (Opnd, Name_Req => True),
3343 Attribute_Name => Name_Length)));
3347 -- Set next entry in aggregate length array
3349 -- For first entry, make either integer literal for fixed length
3350 -- or a reference to the saved length for variable length.
3353 if Is_Fixed_Length (1) then
3354 Aggr_Length (1) := Make_Integer_Literal (Loc, Fixed_Length (1));
3356 Aggr_Length (1) := New_Occurrence_Of (Var_Length (1), Loc);
3359 -- If entry is fixed length and only fixed lengths so far, make
3360 -- appropriate new integer literal adding new length.
3362 elsif Is_Fixed_Length (NN)
3363 and then Nkind (Aggr_Length (NN - 1)) = N_Integer_Literal
3366 Make_Integer_Literal (Loc,
3367 Intval => Fixed_Length (NN) + Intval (Aggr_Length (NN - 1)));
3369 -- All other cases, construct an addition node for the length and
3370 -- create an entity initialized to this length.
3373 Ent := Make_Temporary (Loc, 'L');
3375 if Is_Fixed_Length (NN) then
3376 Clen := Make_Integer_Literal (Loc, Fixed_Length (NN));
3378 Clen := New_Occurrence_Of (Var_Length (NN), Loc);
3382 Make_Object_Declaration (Loc,
3383 Defining_Identifier => Ent,
3384 Constant_Present => True,
3385 Object_Definition => New_Occurrence_Of (Artyp, Loc),
3388 Left_Opnd => New_Copy (Aggr_Length (NN - 1)),
3389 Right_Opnd => Clen)));
3391 Aggr_Length (NN) := Make_Identifier (Loc, Chars => Chars (Ent));
3398 -- If we have only skipped null operands, return the last operand
3405 -- If we have only one non-null operand, return it and we are done.
3406 -- There is one case in which this cannot be done, and that is when
3407 -- the sole operand is of the element type, in which case it must be
3408 -- converted to an array, and the easiest way of doing that is to go
3409 -- through the normal general circuit.
3411 if NN = 1 and then Base_Type (Etype (Operands (1))) /= Ctyp then
3412 Result := Operands (1);
3416 -- Cases where we have a real concatenation
3418 -- Next step is to find the low bound for the result array that we
3419 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
3421 -- If the ultimate ancestor of the index subtype is a constrained array
3422 -- definition, then the lower bound is that of the index subtype as
3423 -- specified by (RM 4.5.3(6)).
3425 -- The right test here is to go to the root type, and then the ultimate
3426 -- ancestor is the first subtype of this root type.
3428 if Is_Constrained (First_Subtype (Root_Type (Atyp))) then
3430 Make_Attribute_Reference (Loc,
3432 New_Occurrence_Of (First_Subtype (Root_Type (Atyp)), Loc),
3433 Attribute_Name => Name_First);
3435 -- If the first operand in the list has known length we know that
3436 -- the lower bound of the result is the lower bound of this operand.
3438 elsif Is_Fixed_Length (1) then
3439 Low_Bound := Opnd_Low_Bound (1);
3441 -- OK, we don't know the lower bound, we have to build a horrible
3442 -- if expression node of the form
3444 -- if Cond1'Length /= 0 then
3447 -- if Opnd2'Length /= 0 then
3452 -- The nesting ends either when we hit an operand whose length is known
3453 -- at compile time, or on reaching the last operand, whose low bound we
3454 -- take unconditionally whether or not it is null. It's easiest to do
3455 -- this with a recursive procedure:
3459 function Get_Known_Bound (J : Nat) return Node_Id;
3460 -- Returns the lower bound determined by operands J .. NN
3462 ---------------------
3463 -- Get_Known_Bound --
3464 ---------------------
3466 function Get_Known_Bound (J : Nat) return Node_Id is
3468 if Is_Fixed_Length (J) or else J = NN then
3469 return New_Copy (Opnd_Low_Bound (J));
3473 Make_If_Expression (Loc,
3474 Expressions => New_List (
3478 New_Occurrence_Of (Var_Length (J), Loc),
3480 Make_Integer_Literal (Loc, 0)),
3482 New_Copy (Opnd_Low_Bound (J)),
3483 Get_Known_Bound (J + 1)));
3485 end Get_Known_Bound;
3488 Ent := Make_Temporary (Loc, 'L');
3491 Make_Object_Declaration (Loc,
3492 Defining_Identifier => Ent,
3493 Constant_Present => True,
3494 Object_Definition => New_Occurrence_Of (Ityp, Loc),
3495 Expression => Get_Known_Bound (1)));
3497 Low_Bound := New_Occurrence_Of (Ent, Loc);
3501 -- Now we can safely compute the upper bound, normally
3502 -- Low_Bound + Length - 1.
3507 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
3509 Make_Op_Subtract (Loc,
3510 Left_Opnd => New_Copy (Aggr_Length (NN)),
3511 Right_Opnd => Make_Artyp_Literal (1))));
3513 -- Note that calculation of the high bound may cause overflow in some
3514 -- very weird cases, so in the general case we need an overflow check on
3515 -- the high bound. We can avoid this for the common case of string types
3516 -- and other types whose index is Positive, since we chose a wider range
3517 -- for the arithmetic type.
3519 if Istyp /= Standard_Positive then
3520 Activate_Overflow_Check (High_Bound);
3523 -- Handle the exceptional case where the result is null, in which case
3524 -- case the bounds come from the last operand (so that we get the proper
3525 -- bounds if the last operand is super-flat).
3527 if Result_May_Be_Null then
3529 Make_If_Expression (Loc,
3530 Expressions => New_List (
3532 Left_Opnd => New_Copy (Aggr_Length (NN)),
3533 Right_Opnd => Make_Artyp_Literal (0)),
3534 Last_Opnd_Low_Bound,
3538 Make_If_Expression (Loc,
3539 Expressions => New_List (
3541 Left_Opnd => New_Copy (Aggr_Length (NN)),
3542 Right_Opnd => Make_Artyp_Literal (0)),
3543 Last_Opnd_High_Bound,
3547 -- Here is where we insert the saved up actions
3549 Insert_Actions (Cnode, Actions, Suppress => All_Checks);
3551 -- Now we construct an array object with appropriate bounds. We mark
3552 -- the target as internal to prevent useless initialization when
3553 -- Initialize_Scalars is enabled. Also since this is the actual result
3554 -- entity, we make sure we have debug information for the result.
3556 Ent := Make_Temporary (Loc, 'S');
3557 Set_Is_Internal (Ent);
3558 Set_Needs_Debug_Info (Ent);
3560 -- If the bound is statically known to be out of range, we do not want
3561 -- to abort, we want a warning and a runtime constraint error. Note that
3562 -- we have arranged that the result will not be treated as a static
3563 -- constant, so we won't get an illegality during this insertion.
3565 Insert_Action (Cnode,
3566 Make_Object_Declaration (Loc,
3567 Defining_Identifier => Ent,
3568 Object_Definition =>
3569 Make_Subtype_Indication (Loc,
3570 Subtype_Mark => New_Occurrence_Of (Atyp, Loc),
3572 Make_Index_Or_Discriminant_Constraint (Loc,
3573 Constraints => New_List (
3575 Low_Bound => Low_Bound,
3576 High_Bound => High_Bound))))),
3577 Suppress => All_Checks);
3579 -- If the result of the concatenation appears as the initializing
3580 -- expression of an object declaration, we can just rename the
3581 -- result, rather than copying it.
3583 Set_OK_To_Rename (Ent);
3585 -- Catch the static out of range case now
3587 if Raises_Constraint_Error (High_Bound) then
3588 raise Concatenation_Error;
3591 -- Now we will generate the assignments to do the actual concatenation
3593 -- There is one case in which we will not do this, namely when all the
3594 -- following conditions are met:
3596 -- The result type is Standard.String
3598 -- There are nine or fewer retained (non-null) operands
3600 -- The optimization level is -O0
3602 -- The corresponding System.Concat_n.Str_Concat_n routine is
3603 -- available in the run time.
3605 -- The debug flag gnatd.c is not set
3607 -- If all these conditions are met then we generate a call to the
3608 -- relevant concatenation routine. The purpose of this is to avoid
3609 -- undesirable code bloat at -O0.
3611 if Atyp = Standard_String
3612 and then NN in 2 .. 9
3613 and then (Lib_Level_Target
3614 or else ((Optimization_Level = 0 or else Debug_Flag_Dot_CC)
3615 and then not Debug_Flag_Dot_C))
3618 RR : constant array (Nat range 2 .. 9) of RE_Id :=
3629 if RTE_Available (RR (NN)) then
3631 Opnds : constant List_Id :=
3632 New_List (New_Occurrence_Of (Ent, Loc));
3635 for J in 1 .. NN loop
3636 if Is_List_Member (Operands (J)) then
3637 Remove (Operands (J));
3640 if Base_Type (Etype (Operands (J))) = Ctyp then
3642 Make_Aggregate (Loc,
3643 Component_Associations => New_List (
3644 Make_Component_Association (Loc,
3645 Choices => New_List (
3646 Make_Integer_Literal (Loc, 1)),
3647 Expression => Operands (J)))));
3650 Append_To (Opnds, Operands (J));
3654 Insert_Action (Cnode,
3655 Make_Procedure_Call_Statement (Loc,
3656 Name => New_Occurrence_Of (RTE (RR (NN)), Loc),
3657 Parameter_Associations => Opnds));
3659 Result := New_Occurrence_Of (Ent, Loc);
3666 -- Not special case so generate the assignments
3668 Known_Non_Null_Operand_Seen := False;
3670 for J in 1 .. NN loop
3672 Lo : constant Node_Id :=
3674 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
3675 Right_Opnd => Aggr_Length (J - 1));
3677 Hi : constant Node_Id :=
3679 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
3681 Make_Op_Subtract (Loc,
3682 Left_Opnd => Aggr_Length (J),
3683 Right_Opnd => Make_Artyp_Literal (1)));
3686 -- Singleton case, simple assignment
3688 if Base_Type (Etype (Operands (J))) = Ctyp then
3689 Known_Non_Null_Operand_Seen := True;
3690 Insert_Action (Cnode,
3691 Make_Assignment_Statement (Loc,
3693 Make_Indexed_Component (Loc,
3694 Prefix => New_Occurrence_Of (Ent, Loc),
3695 Expressions => New_List (To_Ityp (Lo))),
3696 Expression => Operands (J)),
3697 Suppress => All_Checks);
3699 -- Array case, slice assignment, skipped when argument is fixed
3700 -- length and known to be null.
3702 elsif (not Is_Fixed_Length (J)) or else (Fixed_Length (J) > 0) then
3705 Make_Assignment_Statement (Loc,
3709 New_Occurrence_Of (Ent, Loc),
3712 Low_Bound => To_Ityp (Lo),
3713 High_Bound => To_Ityp (Hi))),
3714 Expression => Operands (J));
3716 if Is_Fixed_Length (J) then
3717 Known_Non_Null_Operand_Seen := True;
3719 elsif not Known_Non_Null_Operand_Seen then
3721 -- Here if operand length is not statically known and no
3722 -- operand known to be non-null has been processed yet.
3723 -- If operand length is 0, we do not need to perform the
3724 -- assignment, and we must avoid the evaluation of the
3725 -- high bound of the slice, since it may underflow if the
3726 -- low bound is Ityp'First.
3729 Make_Implicit_If_Statement (Cnode,
3733 New_Occurrence_Of (Var_Length (J), Loc),
3734 Right_Opnd => Make_Integer_Literal (Loc, 0)),
3735 Then_Statements => New_List (Assign));
3738 Insert_Action (Cnode, Assign, Suppress => All_Checks);
3744 -- Finally we build the result, which is a reference to the array object
3746 Result := New_Occurrence_Of (Ent, Loc);
3749 Rewrite (Cnode, Result);
3750 Analyze_And_Resolve (Cnode, Atyp);
3753 when Concatenation_Error =>
3755 -- Kill warning generated for the declaration of the static out of
3756 -- range high bound, and instead generate a Constraint_Error with
3757 -- an appropriate specific message.
3759 Kill_Dead_Code (Declaration_Node (Entity (High_Bound)));
3760 Apply_Compile_Time_Constraint_Error
3762 Msg => "concatenation result upper bound out of range??",
3763 Reason => CE_Range_Check_Failed);
3764 end Expand_Concatenate;
3766 ---------------------------------------------------
3767 -- Expand_Membership_Minimize_Eliminate_Overflow --
3768 ---------------------------------------------------
3770 procedure Expand_Membership_Minimize_Eliminate_Overflow (N : Node_Id) is
3771 pragma Assert (Nkind (N) = N_In);
3772 -- Despite the name, this routine applies only to N_In, not to
3773 -- N_Not_In. The latter is always rewritten as not (X in Y).
3775 Result_Type : constant Entity_Id := Etype (N);
3776 -- Capture result type, may be a derived boolean type
3778 Loc : constant Source_Ptr := Sloc (N);
3779 Lop : constant Node_Id := Left_Opnd (N);
3780 Rop : constant Node_Id := Right_Opnd (N);
3782 -- Note: there are many referencs to Etype (Lop) and Etype (Rop). It
3783 -- is thus tempting to capture these values, but due to the rewrites
3784 -- that occur as a result of overflow checking, these values change
3785 -- as we go along, and it is safe just to always use Etype explicitly.
3787 Restype : constant Entity_Id := Etype (N);
3791 -- Bounds in Minimize calls, not used currently
3793 LLIB : constant Entity_Id := Base_Type (Standard_Long_Long_Integer);
3794 -- Entity for Long_Long_Integer'Base (Standard should export this???)
3797 Minimize_Eliminate_Overflows (Lop, Lo, Hi, Top_Level => False);
3799 -- If right operand is a subtype name, and the subtype name has no
3800 -- predicate, then we can just replace the right operand with an
3801 -- explicit range T'First .. T'Last, and use the explicit range code.
3803 if Nkind (Rop) /= N_Range
3804 and then No (Predicate_Function (Etype (Rop)))
3807 Rtyp : constant Entity_Id := Etype (Rop);
3812 Make_Attribute_Reference (Loc,
3813 Attribute_Name => Name_First,
3814 Prefix => New_Occurrence_Of (Rtyp, Loc)),
3816 Make_Attribute_Reference (Loc,
3817 Attribute_Name => Name_Last,
3818 Prefix => New_Occurrence_Of (Rtyp, Loc))));
3819 Analyze_And_Resolve (Rop, Rtyp, Suppress => All_Checks);
3823 -- Here for the explicit range case. Note that the bounds of the range
3824 -- have not been processed for minimized or eliminated checks.
3826 if Nkind (Rop) = N_Range then
3827 Minimize_Eliminate_Overflows
3828 (Low_Bound (Rop), Lo, Hi, Top_Level => False);
3829 Minimize_Eliminate_Overflows
3830 (High_Bound (Rop), Lo, Hi, Top_Level => False);
3832 -- We have A in B .. C, treated as A >= B and then A <= C
3836 if Is_RTE (Etype (Lop), RE_Bignum)
3837 or else Is_RTE (Etype (Low_Bound (Rop)), RE_Bignum)
3838 or else Is_RTE (Etype (High_Bound (Rop)), RE_Bignum)
3841 Blk : constant Node_Id := Make_Bignum_Block (Loc);
3842 Bnn : constant Entity_Id := Make_Temporary (Loc, 'B', N);
3843 L : constant Entity_Id :=
3844 Make_Defining_Identifier (Loc, Name_uL);
3845 Lopnd : constant Node_Id := Convert_To_Bignum (Lop);
3846 Lbound : constant Node_Id :=
3847 Convert_To_Bignum (Low_Bound (Rop));
3848 Hbound : constant Node_Id :=
3849 Convert_To_Bignum (High_Bound (Rop));
3851 -- Now we rewrite the membership test node to look like
3854 -- Bnn : Result_Type;
3856 -- M : Mark_Id := SS_Mark;
3857 -- L : Bignum := Lopnd;
3859 -- Bnn := Big_GE (L, Lbound) and then Big_LE (L, Hbound)
3867 -- Insert declaration of L into declarations of bignum block
3870 (Last (Declarations (Blk)),
3871 Make_Object_Declaration (Loc,
3872 Defining_Identifier => L,
3873 Object_Definition =>
3874 New_Occurrence_Of (RTE (RE_Bignum), Loc),
3875 Expression => Lopnd));
3877 -- Insert assignment to Bnn into expressions of bignum block
3880 (First (Statements (Handled_Statement_Sequence (Blk))),
3881 Make_Assignment_Statement (Loc,
3882 Name => New_Occurrence_Of (Bnn, Loc),
3886 Make_Function_Call (Loc,
3888 New_Occurrence_Of (RTE (RE_Big_GE), Loc),
3889 Parameter_Associations => New_List (
3890 New_Occurrence_Of (L, Loc),
3894 Make_Function_Call (Loc,
3896 New_Occurrence_Of (RTE (RE_Big_LE), Loc),
3897 Parameter_Associations => New_List (
3898 New_Occurrence_Of (L, Loc),
3901 -- Now rewrite the node
3904 Make_Expression_With_Actions (Loc,
3905 Actions => New_List (
3906 Make_Object_Declaration (Loc,
3907 Defining_Identifier => Bnn,
3908 Object_Definition =>
3909 New_Occurrence_Of (Result_Type, Loc)),
3911 Expression => New_Occurrence_Of (Bnn, Loc)));
3912 Analyze_And_Resolve (N, Result_Type);
3916 -- Here if no bignums around
3919 -- Case where types are all the same
3921 if Base_Type (Etype (Lop)) = Base_Type (Etype (Low_Bound (Rop)))
3923 Base_Type (Etype (Lop)) = Base_Type (Etype (High_Bound (Rop)))
3927 -- If types are not all the same, it means that we have rewritten
3928 -- at least one of them to be of type Long_Long_Integer, and we
3929 -- will convert the other operands to Long_Long_Integer.
3932 Convert_To_And_Rewrite (LLIB, Lop);
3933 Set_Analyzed (Lop, False);
3934 Analyze_And_Resolve (Lop, LLIB);
3936 -- For the right operand, avoid unnecessary recursion into
3937 -- this routine, we know that overflow is not possible.
3939 Convert_To_And_Rewrite (LLIB, Low_Bound (Rop));
3940 Convert_To_And_Rewrite (LLIB, High_Bound (Rop));
3941 Set_Analyzed (Rop, False);
3942 Analyze_And_Resolve (Rop, LLIB, Suppress => Overflow_Check);
3945 -- Now the three operands are of the same signed integer type,
3946 -- so we can use the normal expansion routine for membership,
3947 -- setting the flag to prevent recursion into this procedure.
3949 Set_No_Minimize_Eliminate (N);
3953 -- Right operand is a subtype name and the subtype has a predicate. We
3954 -- have to make sure the predicate is checked, and for that we need to
3955 -- use the standard N_In circuitry with appropriate types.
3958 pragma Assert (Present (Predicate_Function (Etype (Rop))));
3960 -- If types are "right", just call Expand_N_In preventing recursion
3962 if Base_Type (Etype (Lop)) = Base_Type (Etype (Rop)) then
3963 Set_No_Minimize_Eliminate (N);
3968 elsif Is_RTE (Etype (Lop), RE_Bignum) then
3970 -- For X in T, we want to rewrite our node as
3973 -- Bnn : Result_Type;
3976 -- M : Mark_Id := SS_Mark;
3977 -- Lnn : Long_Long_Integer'Base
3983 -- if not Bignum_In_LLI_Range (Nnn) then
3986 -- Lnn := From_Bignum (Nnn);
3988 -- Lnn in LLIB (T'Base'First) .. LLIB (T'Base'Last)
3989 -- and then T'Base (Lnn) in T;
3998 -- A bit gruesome, but there doesn't seem to be a simpler way
4001 Blk : constant Node_Id := Make_Bignum_Block (Loc);
4002 Bnn : constant Entity_Id := Make_Temporary (Loc, 'B', N);
4003 Lnn : constant Entity_Id := Make_Temporary (Loc, 'L', N);
4004 Nnn : constant Entity_Id := Make_Temporary (Loc, 'N', N);
4005 T : constant Entity_Id := Etype (Rop);
4006 TB : constant Entity_Id := Base_Type (T);
4010 -- Mark the last membership operation to prevent recursion
4014 Left_Opnd => Convert_To (TB, New_Occurrence_Of (Lnn, Loc)),
4015 Right_Opnd => New_Occurrence_Of (T, Loc));
4016 Set_No_Minimize_Eliminate (Nin);
4018 -- Now decorate the block
4021 (Last (Declarations (Blk)),
4022 Make_Object_Declaration (Loc,
4023 Defining_Identifier => Lnn,
4024 Object_Definition => New_Occurrence_Of (LLIB, Loc)));
4027 (Last (Declarations (Blk)),
4028 Make_Object_Declaration (Loc,
4029 Defining_Identifier => Nnn,
4030 Object_Definition =>
4031 New_Occurrence_Of (RTE (RE_Bignum), Loc)));
4034 (First (Statements (Handled_Statement_Sequence (Blk))),
4036 Make_Assignment_Statement (Loc,
4037 Name => New_Occurrence_Of (Nnn, Loc),
4038 Expression => Relocate_Node (Lop)),
4040 Make_Implicit_If_Statement (N,
4044 Make_Function_Call (Loc,
4047 (RTE (RE_Bignum_In_LLI_Range), Loc),
4048 Parameter_Associations => New_List (
4049 New_Occurrence_Of (Nnn, Loc)))),
4051 Then_Statements => New_List (
4052 Make_Assignment_Statement (Loc,
4053 Name => New_Occurrence_Of (Bnn, Loc),
4055 New_Occurrence_Of (Standard_False, Loc))),
4057 Else_Statements => New_List (
4058 Make_Assignment_Statement (Loc,
4059 Name => New_Occurrence_Of (Lnn, Loc),
4061 Make_Function_Call (Loc,
4063 New_Occurrence_Of (RTE (RE_From_Bignum), Loc),
4064 Parameter_Associations => New_List (
4065 New_Occurrence_Of (Nnn, Loc)))),
4067 Make_Assignment_Statement (Loc,
4068 Name => New_Occurrence_Of (Bnn, Loc),
4073 Left_Opnd => New_Occurrence_Of (Lnn, Loc),
4078 Make_Attribute_Reference (Loc,
4079 Attribute_Name => Name_First,
4081 New_Occurrence_Of (TB, Loc))),
4085 Make_Attribute_Reference (Loc,
4086 Attribute_Name => Name_Last,
4088 New_Occurrence_Of (TB, Loc))))),
4090 Right_Opnd => Nin))))));
4092 -- Now we can do the rewrite
4095 Make_Expression_With_Actions (Loc,
4096 Actions => New_List (
4097 Make_Object_Declaration (Loc,
4098 Defining_Identifier => Bnn,
4099 Object_Definition =>
4100 New_Occurrence_Of (Result_Type, Loc)),
4102 Expression => New_Occurrence_Of (Bnn, Loc)));
4103 Analyze_And_Resolve (N, Result_Type);
4107 -- Not bignum case, but types don't match (this means we rewrote the
4108 -- left operand to be Long_Long_Integer).
4111 pragma Assert (Base_Type (Etype (Lop)) = LLIB);
4113 -- We rewrite the membership test as (where T is the type with
4114 -- the predicate, i.e. the type of the right operand)
4116 -- Lop in LLIB (T'Base'First) .. LLIB (T'Base'Last)
4117 -- and then T'Base (Lop) in T
4120 T : constant Entity_Id := Etype (Rop);
4121 TB : constant Entity_Id := Base_Type (T);
4125 -- The last membership test is marked to prevent recursion
4129 Left_Opnd => Convert_To (TB, Duplicate_Subexpr (Lop)),
4130 Right_Opnd => New_Occurrence_Of (T, Loc));
4131 Set_No_Minimize_Eliminate (Nin);
4133 -- Now do the rewrite
4144 Make_Attribute_Reference (Loc,
4145 Attribute_Name => Name_First,
4147 New_Occurrence_Of (TB, Loc))),
4150 Make_Attribute_Reference (Loc,
4151 Attribute_Name => Name_Last,
4153 New_Occurrence_Of (TB, Loc))))),
4154 Right_Opnd => Nin));
4155 Set_Analyzed (N, False);
4156 Analyze_And_Resolve (N, Restype);
4160 end Expand_Membership_Minimize_Eliminate_Overflow;
4162 ------------------------
4163 -- Expand_N_Allocator --
4164 ------------------------
4166 procedure Expand_N_Allocator (N : Node_Id) is
4167 Etyp : constant Entity_Id := Etype (Expression (N));
4168 Loc : constant Source_Ptr := Sloc (N);
4169 PtrT : constant Entity_Id := Etype (N);
4171 procedure Rewrite_Coextension (N : Node_Id);
4172 -- Static coextensions have the same lifetime as the entity they
4173 -- constrain. Such occurrences can be rewritten as aliased objects
4174 -- and their unrestricted access used instead of the coextension.
4176 function Size_In_Storage_Elements (E : Entity_Id) return Node_Id;
4177 -- Given a constrained array type E, returns a node representing the
4178 -- code to compute the size in storage elements for the given type.
4179 -- This is done without using the attribute (which malfunctions for
4182 -------------------------
4183 -- Rewrite_Coextension --
4184 -------------------------
4186 procedure Rewrite_Coextension (N : Node_Id) is
4187 Temp_Id : constant Node_Id := Make_Temporary (Loc, 'C');
4188 Temp_Decl : Node_Id;
4192 -- Cnn : aliased Etyp;
4195 Make_Object_Declaration (Loc,
4196 Defining_Identifier => Temp_Id,
4197 Aliased_Present => True,
4198 Object_Definition => New_Occurrence_Of (Etyp, Loc));
4200 if Nkind (Expression (N)) = N_Qualified_Expression then
4201 Set_Expression (Temp_Decl, Expression (Expression (N)));
4204 Insert_Action (N, Temp_Decl);
4206 Make_Attribute_Reference (Loc,
4207 Prefix => New_Occurrence_Of (Temp_Id, Loc),
4208 Attribute_Name => Name_Unrestricted_Access));
4210 Analyze_And_Resolve (N, PtrT);
4211 end Rewrite_Coextension;
4213 ------------------------------
4214 -- Size_In_Storage_Elements --
4215 ------------------------------
4217 function Size_In_Storage_Elements (E : Entity_Id) return Node_Id is
4219 -- Logically this just returns E'Max_Size_In_Storage_Elements.
4220 -- However, the reason for the existence of this function is
4221 -- to construct a test for sizes too large, which means near the
4222 -- 32-bit limit on a 32-bit machine, and precisely the trouble
4223 -- is that we get overflows when sizes are greater than 2**31.
4225 -- So what we end up doing for array types is to use the expression:
4227 -- number-of-elements * component_type'Max_Size_In_Storage_Elements
4229 -- which avoids this problem. All this is a bit bogus, but it does
4230 -- mean we catch common cases of trying to allocate arrays that
4231 -- are too large, and which in the absence of a check results in
4232 -- undetected chaos ???
4234 -- Note in particular that this is a pessimistic estimate in the
4235 -- case of packed array types, where an array element might occupy
4236 -- just a fraction of a storage element???
4243 for J in 1 .. Number_Dimensions (E) loop
4245 Make_Attribute_Reference (Loc,
4246 Prefix => New_Occurrence_Of (E, Loc),
4247 Attribute_Name => Name_Length,
4248 Expressions => New_List (Make_Integer_Literal (Loc, J)));
4255 Make_Op_Multiply (Loc,
4262 Make_Op_Multiply (Loc,
4265 Make_Attribute_Reference (Loc,
4266 Prefix => New_Occurrence_Of (Component_Type (E), Loc),
4267 Attribute_Name => Name_Max_Size_In_Storage_Elements));
4269 end Size_In_Storage_Elements;
4273 Dtyp : constant Entity_Id := Available_View (Designated_Type (PtrT));
4277 Rel_Typ : Entity_Id;
4280 -- Start of processing for Expand_N_Allocator
4283 -- RM E.2.3(22). We enforce that the expected type of an allocator
4284 -- shall not be a remote access-to-class-wide-limited-private type
4286 -- Why is this being done at expansion time, seems clearly wrong ???
4288 Validate_Remote_Access_To_Class_Wide_Type (N);
4290 -- Processing for anonymous access-to-controlled types. These access
4291 -- types receive a special finalization master which appears in the
4292 -- declarations of the enclosing semantic unit. This expansion is done
4293 -- now to ensure that any additional types generated by this routine or
4294 -- Expand_Allocator_Expression inherit the proper type attributes.
4296 if (Ekind (PtrT) = E_Anonymous_Access_Type
4297 or else (Is_Itype (PtrT) and then No (Finalization_Master (PtrT))))
4298 and then Needs_Finalization (Dtyp)
4300 -- Detect the allocation of an anonymous controlled object where the
4301 -- type of the context is named. For example:
4303 -- procedure Proc (Ptr : Named_Access_Typ);
4304 -- Proc (new Designated_Typ);
4306 -- Regardless of the anonymous-to-named access type conversion, the
4307 -- lifetime of the object must be associated with the named access
4308 -- type. Use the finalization-related attributes of this type.
4310 if Nkind_In (Parent (N), N_Type_Conversion,
4311 N_Unchecked_Type_Conversion)
4312 and then Ekind_In (Etype (Parent (N)), E_Access_Subtype,
4314 E_General_Access_Type)
4316 Rel_Typ := Etype (Parent (N));
4321 -- Anonymous access-to-controlled types allocate on the global pool.
4322 -- Do not set this attribute on .NET/JVM since those targets do not
4323 -- support pools. Note that this is a "root type only" attribute.
4325 if No (Associated_Storage_Pool (PtrT)) and then VM_Target = No_VM then
4326 if Present (Rel_Typ) then
4327 Set_Associated_Storage_Pool
4328 (Root_Type (PtrT), Associated_Storage_Pool (Rel_Typ));
4330 Set_Associated_Storage_Pool
4331 (Root_Type (PtrT), RTE (RE_Global_Pool_Object));
4335 -- The finalization master must be inserted and analyzed as part of
4336 -- the current semantic unit. Note that the master is updated when
4337 -- analysis changes current units. Note that this is a "root type
4340 if Present (Rel_Typ) then
4341 Set_Finalization_Master
4342 (Root_Type (PtrT), Finalization_Master (Rel_Typ));
4344 Set_Finalization_Master
4345 (Root_Type (PtrT), Current_Anonymous_Master);
4349 -- Set the storage pool and find the appropriate version of Allocate to
4350 -- call. Do not overwrite the storage pool if it is already set, which
4351 -- can happen for build-in-place function returns (see
4352 -- Exp_Ch4.Expand_N_Extended_Return_Statement).
4354 if No (Storage_Pool (N)) then
4355 Pool := Associated_Storage_Pool (Root_Type (PtrT));
4357 if Present (Pool) then
4358 Set_Storage_Pool (N, Pool);
4360 if Is_RTE (Pool, RE_SS_Pool) then
4361 if VM_Target = No_VM then
4362 Set_Procedure_To_Call (N, RTE (RE_SS_Allocate));
4365 -- In the case of an allocator for a simple storage pool, locate
4366 -- and save a reference to the pool type's Allocate routine.
4368 elsif Present (Get_Rep_Pragma
4369 (Etype (Pool), Name_Simple_Storage_Pool_Type))
4372 Pool_Type : constant Entity_Id := Base_Type (Etype (Pool));
4373 Alloc_Op : Entity_Id;
4375 Alloc_Op := Get_Name_Entity_Id (Name_Allocate);
4376 while Present (Alloc_Op) loop
4377 if Scope (Alloc_Op) = Scope (Pool_Type)
4378 and then Present (First_Formal (Alloc_Op))
4379 and then Etype (First_Formal (Alloc_Op)) = Pool_Type
4381 Set_Procedure_To_Call (N, Alloc_Op);
4384 Alloc_Op := Homonym (Alloc_Op);
4389 elsif Is_Class_Wide_Type (Etype (Pool)) then
4390 Set_Procedure_To_Call (N, RTE (RE_Allocate_Any));
4393 Set_Procedure_To_Call (N,
4394 Find_Prim_Op (Etype (Pool), Name_Allocate));
4399 -- Under certain circumstances we can replace an allocator by an access
4400 -- to statically allocated storage. The conditions, as noted in AARM
4401 -- 3.10 (10c) are as follows:
4403 -- Size and initial value is known at compile time
4404 -- Access type is access-to-constant
4406 -- The allocator is not part of a constraint on a record component,
4407 -- because in that case the inserted actions are delayed until the
4408 -- record declaration is fully analyzed, which is too late for the
4409 -- analysis of the rewritten allocator.
4411 if Is_Access_Constant (PtrT)
4412 and then Nkind (Expression (N)) = N_Qualified_Expression
4413 and then Compile_Time_Known_Value (Expression (Expression (N)))
4414 and then Size_Known_At_Compile_Time
4415 (Etype (Expression (Expression (N))))
4416 and then not Is_Record_Type (Current_Scope)
4418 -- Here we can do the optimization. For the allocator
4422 -- We insert an object declaration
4424 -- Tnn : aliased x := y;
4426 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
4427 -- marked as requiring static allocation.
4429 Temp := Make_Temporary (Loc, 'T', Expression (Expression (N)));
4430 Desig := Subtype_Mark (Expression (N));
4432 -- If context is constrained, use constrained subtype directly,
4433 -- so that the constant is not labelled as having a nominally
4434 -- unconstrained subtype.
4436 if Entity (Desig) = Base_Type (Dtyp) then
4437 Desig := New_Occurrence_Of (Dtyp, Loc);
4441 Make_Object_Declaration (Loc,
4442 Defining_Identifier => Temp,
4443 Aliased_Present => True,
4444 Constant_Present => Is_Access_Constant (PtrT),
4445 Object_Definition => Desig,
4446 Expression => Expression (Expression (N))));
4449 Make_Attribute_Reference (Loc,
4450 Prefix => New_Occurrence_Of (Temp, Loc),
4451 Attribute_Name => Name_Unrestricted_Access));
4453 Analyze_And_Resolve (N, PtrT);
4455 -- We set the variable as statically allocated, since we don't want
4456 -- it going on the stack of the current procedure.
4458 Set_Is_Statically_Allocated (Temp);
4462 -- Same if the allocator is an access discriminant for a local object:
4463 -- instead of an allocator we create a local value and constrain the
4464 -- enclosing object with the corresponding access attribute.
4466 if Is_Static_Coextension (N) then
4467 Rewrite_Coextension (N);
4471 -- Check for size too large, we do this because the back end misses
4472 -- proper checks here and can generate rubbish allocation calls when
4473 -- we are near the limit. We only do this for the 32-bit address case
4474 -- since that is from a practical point of view where we see a problem.
4476 if System_Address_Size = 32
4477 and then not Storage_Checks_Suppressed (PtrT)
4478 and then not Storage_Checks_Suppressed (Dtyp)
4479 and then not Storage_Checks_Suppressed (Etyp)
4481 -- The check we want to generate should look like
4483 -- if Etyp'Max_Size_In_Storage_Elements > 3.5 gigabytes then
4484 -- raise Storage_Error;
4487 -- where 3.5 gigabytes is a constant large enough to accommodate any
4488 -- reasonable request for. But we can't do it this way because at
4489 -- least at the moment we don't compute this attribute right, and
4490 -- can silently give wrong results when the result gets large. Since
4491 -- this is all about large results, that's bad, so instead we only
4492 -- apply the check for constrained arrays, and manually compute the
4493 -- value of the attribute ???
4495 if Is_Array_Type (Etyp) and then Is_Constrained (Etyp) then
4497 Make_Raise_Storage_Error (Loc,
4500 Left_Opnd => Size_In_Storage_Elements (Etyp),
4502 Make_Integer_Literal (Loc, Uint_7 * (Uint_2 ** 29))),
4503 Reason => SE_Object_Too_Large));
4507 -- If no storage pool has been specified and we have the restriction
4508 -- No_Standard_Allocators_After_Elaboration is present, then generate
4509 -- a call to Elaboration_Allocators.Check_Standard_Allocator.
4511 if Nkind (N) = N_Allocator
4512 and then No (Storage_Pool (N))
4513 and then Restriction_Active (No_Standard_Allocators_After_Elaboration)
4516 Make_Procedure_Call_Statement (Loc,
4518 New_Occurrence_Of (RTE (RE_Check_Standard_Allocator), Loc)));
4521 -- Handle case of qualified expression (other than optimization above)
4522 -- First apply constraint checks, because the bounds or discriminants
4523 -- in the aggregate might not match the subtype mark in the allocator.
4525 if Nkind (Expression (N)) = N_Qualified_Expression then
4526 Apply_Constraint_Check
4527 (Expression (Expression (N)), Etype (Expression (N)));
4529 Expand_Allocator_Expression (N);
4533 -- If the allocator is for a type which requires initialization, and
4534 -- there is no initial value (i.e. operand is a subtype indication
4535 -- rather than a qualified expression), then we must generate a call to
4536 -- the initialization routine using an expressions action node:
4538 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
4540 -- Here ptr_T is the pointer type for the allocator, and T is the
4541 -- subtype of the allocator. A special case arises if the designated
4542 -- type of the access type is a task or contains tasks. In this case
4543 -- the call to Init (Temp.all ...) is replaced by code that ensures
4544 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
4545 -- for details). In addition, if the type T is a task type, then the
4546 -- first argument to Init must be converted to the task record type.
4549 T : constant Entity_Id := Entity (Expression (N));
4555 Init_Arg1 : Node_Id;
4556 Temp_Decl : Node_Id;
4557 Temp_Type : Entity_Id;
4560 if No_Initialization (N) then
4562 -- Even though this might be a simple allocation, create a custom
4563 -- Allocate if the context requires it. Since .NET/JVM compilers
4564 -- do not support pools, this step is skipped.
4566 if VM_Target = No_VM
4567 and then Present (Finalization_Master (PtrT))
4569 Build_Allocate_Deallocate_Proc
4571 Is_Allocate => True);
4574 -- Case of no initialization procedure present
4576 elsif not Has_Non_Null_Base_Init_Proc (T) then
4578 -- Case of simple initialization required
4580 if Needs_Simple_Initialization (T) then
4581 Check_Restriction (No_Default_Initialization, N);
4582 Rewrite (Expression (N),
4583 Make_Qualified_Expression (Loc,
4584 Subtype_Mark => New_Occurrence_Of (T, Loc),
4585 Expression => Get_Simple_Init_Val (T, N)));
4587 Analyze_And_Resolve (Expression (Expression (N)), T);
4588 Analyze_And_Resolve (Expression (N), T);
4589 Set_Paren_Count (Expression (Expression (N)), 1);
4590 Expand_N_Allocator (N);
4592 -- No initialization required
4598 -- Case of initialization procedure present, must be called
4601 Check_Restriction (No_Default_Initialization, N);
4603 if not Restriction_Active (No_Default_Initialization) then
4604 Init := Base_Init_Proc (T);
4606 Temp := Make_Temporary (Loc, 'P');
4608 -- Construct argument list for the initialization routine call
4611 Make_Explicit_Dereference (Loc,
4613 New_Occurrence_Of (Temp, Loc));
4615 Set_Assignment_OK (Init_Arg1);
4618 -- The initialization procedure expects a specific type. if the
4619 -- context is access to class wide, indicate that the object
4620 -- being allocated has the right specific type.
4622 if Is_Class_Wide_Type (Dtyp) then
4623 Init_Arg1 := Unchecked_Convert_To (T, Init_Arg1);
4626 -- If designated type is a concurrent type or if it is private
4627 -- type whose definition is a concurrent type, the first
4628 -- argument in the Init routine has to be unchecked conversion
4629 -- to the corresponding record type. If the designated type is
4630 -- a derived type, also convert the argument to its root type.
4632 if Is_Concurrent_Type (T) then
4634 Unchecked_Convert_To (
4635 Corresponding_Record_Type (T), Init_Arg1);
4637 elsif Is_Private_Type (T)
4638 and then Present (Full_View (T))
4639 and then Is_Concurrent_Type (Full_View (T))
4642 Unchecked_Convert_To
4643 (Corresponding_Record_Type (Full_View (T)), Init_Arg1);
4645 elsif Etype (First_Formal (Init)) /= Base_Type (T) then
4647 Ftyp : constant Entity_Id := Etype (First_Formal (Init));
4650 Init_Arg1 := OK_Convert_To (Etype (Ftyp), Init_Arg1);
4651 Set_Etype (Init_Arg1, Ftyp);
4655 Args := New_List (Init_Arg1);
4657 -- For the task case, pass the Master_Id of the access type as
4658 -- the value of the _Master parameter, and _Chain as the value
4659 -- of the _Chain parameter (_Chain will be defined as part of
4660 -- the generated code for the allocator).
4662 -- In Ada 2005, the context may be a function that returns an
4663 -- anonymous access type. In that case the Master_Id has been
4664 -- created when expanding the function declaration.
4666 if Has_Task (T) then
4667 if No (Master_Id (Base_Type (PtrT))) then
4669 -- The designated type was an incomplete type, and the
4670 -- access type did not get expanded. Salvage it now.
4672 if not Restriction_Active (No_Task_Hierarchy) then
4673 if Present (Parent (Base_Type (PtrT))) then
4674 Expand_N_Full_Type_Declaration
4675 (Parent (Base_Type (PtrT)));
4677 -- The only other possibility is an itype. For this
4678 -- case, the master must exist in the context. This is
4679 -- the case when the allocator initializes an access
4680 -- component in an init-proc.
4683 pragma Assert (Is_Itype (PtrT));
4684 Build_Master_Renaming (PtrT, N);
4689 -- If the context of the allocator is a declaration or an
4690 -- assignment, we can generate a meaningful image for it,
4691 -- even though subsequent assignments might remove the
4692 -- connection between task and entity. We build this image
4693 -- when the left-hand side is a simple variable, a simple
4694 -- indexed assignment or a simple selected component.
4696 if Nkind (Parent (N)) = N_Assignment_Statement then
4698 Nam : constant Node_Id := Name (Parent (N));
4701 if Is_Entity_Name (Nam) then
4703 Build_Task_Image_Decls
4706 (Entity (Nam), Sloc (Nam)), T);
4708 elsif Nkind_In (Nam, N_Indexed_Component,
4709 N_Selected_Component)
4710 and then Is_Entity_Name (Prefix (Nam))
4713 Build_Task_Image_Decls
4714 (Loc, Nam, Etype (Prefix (Nam)));
4716 Decls := Build_Task_Image_Decls (Loc, T, T);
4720 elsif Nkind (Parent (N)) = N_Object_Declaration then
4722 Build_Task_Image_Decls
4723 (Loc, Defining_Identifier (Parent (N)), T);
4726 Decls := Build_Task_Image_Decls (Loc, T, T);
4729 if Restriction_Active (No_Task_Hierarchy) then
4731 New_Occurrence_Of (RTE (RE_Library_Task_Level), Loc));
4735 (Master_Id (Base_Type (Root_Type (PtrT))), Loc));
4738 Append_To (Args, Make_Identifier (Loc, Name_uChain));
4740 Decl := Last (Decls);
4742 New_Occurrence_Of (Defining_Identifier (Decl), Loc));
4744 -- Has_Task is false, Decls not used
4750 -- Add discriminants if discriminated type
4753 Dis : Boolean := False;
4757 if Has_Discriminants (T) then
4761 elsif Is_Private_Type (T)
4762 and then Present (Full_View (T))
4763 and then Has_Discriminants (Full_View (T))
4766 Typ := Full_View (T);
4771 -- If the allocated object will be constrained by the
4772 -- default values for discriminants, then build a subtype
4773 -- with those defaults, and change the allocated subtype
4774 -- to that. Note that this happens in fewer cases in Ada
4777 if not Is_Constrained (Typ)
4778 and then Present (Discriminant_Default_Value
4779 (First_Discriminant (Typ)))
4780 and then (Ada_Version < Ada_2005
4782 Object_Type_Has_Constrained_Partial_View
4783 (Typ, Current_Scope))
4785 Typ := Build_Default_Subtype (Typ, N);
4786 Set_Expression (N, New_Occurrence_Of (Typ, Loc));
4789 Discr := First_Elmt (Discriminant_Constraint (Typ));
4790 while Present (Discr) loop
4791 Nod := Node (Discr);
4792 Append (New_Copy_Tree (Node (Discr)), Args);
4794 -- AI-416: when the discriminant constraint is an
4795 -- anonymous access type make sure an accessibility
4796 -- check is inserted if necessary (3.10.2(22.q/2))
4798 if Ada_Version >= Ada_2005
4800 Ekind (Etype (Nod)) = E_Anonymous_Access_Type
4802 Apply_Accessibility_Check
4803 (Nod, Typ, Insert_Node => Nod);
4811 -- We set the allocator as analyzed so that when we analyze
4812 -- the if expression node, we do not get an unwanted recursive
4813 -- expansion of the allocator expression.
4815 Set_Analyzed (N, True);
4816 Nod := Relocate_Node (N);
4818 -- Here is the transformation:
4819 -- input: new Ctrl_Typ
4820 -- output: Temp : constant Ctrl_Typ_Ptr := new Ctrl_Typ;
4821 -- Ctrl_TypIP (Temp.all, ...);
4822 -- [Deep_]Initialize (Temp.all);
4824 -- Here Ctrl_Typ_Ptr is the pointer type for the allocator, and
4825 -- is the subtype of the allocator.
4828 Make_Object_Declaration (Loc,
4829 Defining_Identifier => Temp,
4830 Constant_Present => True,
4831 Object_Definition => New_Occurrence_Of (Temp_Type, Loc),
4834 Set_Assignment_OK (Temp_Decl);
4835 Insert_Action (N, Temp_Decl, Suppress => All_Checks);
4837 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
4839 -- If the designated type is a task type or contains tasks,
4840 -- create block to activate created tasks, and insert
4841 -- declaration for Task_Image variable ahead of call.
4843 if Has_Task (T) then
4845 L : constant List_Id := New_List;
4848 Build_Task_Allocate_Block (L, Nod, Args);
4850 Insert_List_Before (First (Declarations (Blk)), Decls);
4851 Insert_Actions (N, L);
4856 Make_Procedure_Call_Statement (Loc,
4857 Name => New_Occurrence_Of (Init, Loc),
4858 Parameter_Associations => Args));
4861 if Needs_Finalization (T) then
4864 -- [Deep_]Initialize (Init_Arg1);
4868 (Obj_Ref => New_Copy_Tree (Init_Arg1),
4871 if Present (Finalization_Master (PtrT)) then
4873 -- Special processing for .NET/JVM, the allocated object
4874 -- is attached to the finalization master. Generate:
4876 -- Attach (<PtrT>FM, Root_Controlled_Ptr (Init_Arg1));
4878 -- Types derived from [Limited_]Controlled are the only
4879 -- ones considered since they have fields Prev and Next.
4881 if VM_Target /= No_VM then
4882 if Is_Controlled (T) then
4885 (Obj_Ref => New_Copy_Tree (Init_Arg1),
4889 -- Default case, generate:
4891 -- Set_Finalize_Address
4892 -- (<PtrT>FM, <T>FD'Unrestricted_Access);
4894 -- Do not generate this call in CodePeer mode, as TSS
4895 -- primitive Finalize_Address is not created in this
4898 elsif not CodePeer_Mode then
4900 Make_Set_Finalize_Address_Call
4908 Rewrite (N, New_Occurrence_Of (Temp, Loc));
4909 Analyze_And_Resolve (N, PtrT);
4914 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
4915 -- object that has been rewritten as a reference, we displace "this"
4916 -- to reference properly its secondary dispatch table.
4918 if Nkind (N) = N_Identifier and then Is_Interface (Dtyp) then
4919 Displace_Allocator_Pointer (N);
4923 when RE_Not_Available =>
4925 end Expand_N_Allocator;
4927 -----------------------
4928 -- Expand_N_And_Then --
4929 -----------------------
4931 procedure Expand_N_And_Then (N : Node_Id)
4932 renames Expand_Short_Circuit_Operator;
4934 ------------------------------
4935 -- Expand_N_Case_Expression --
4936 ------------------------------
4938 procedure Expand_N_Case_Expression (N : Node_Id) is
4939 Loc : constant Source_Ptr := Sloc (N);
4940 Typ : constant Entity_Id := Etype (N);
4951 -- Check for MINIMIZED/ELIMINATED overflow mode
4953 if Minimized_Eliminated_Overflow_Check (N) then
4954 Apply_Arithmetic_Overflow_Check (N);
4958 -- If the case expression is a predicate specification, do not
4959 -- expand, because it will be converted to the proper predicate
4960 -- form when building the predicate function.
4962 if Ekind_In (Current_Scope, E_Function, E_Procedure)
4963 and then Is_Predicate_Function (Current_Scope)
4970 -- case X is when A => AX, when B => BX ...
4985 -- However, this expansion is wrong for limited types, and also
4986 -- wrong for unconstrained types (since the bounds may not be the
4987 -- same in all branches). Furthermore it involves an extra copy
4988 -- for large objects. So we take care of this by using the following
4989 -- modified expansion for non-elementary types:
4992 -- type Pnn is access all typ;
4996 -- T := AX'Unrestricted_Access;
4998 -- T := BX'Unrestricted_Access;
5004 Make_Case_Statement (Loc,
5005 Expression => Expression (N),
5006 Alternatives => New_List);
5008 -- Preserve the original context for which the case statement is being
5009 -- generated. This is needed by the finalization machinery to prevent
5010 -- the premature finalization of controlled objects found within the
5013 Set_From_Conditional_Expression (Cstmt);
5015 Actions := New_List;
5019 if Is_Elementary_Type (Typ) then
5023 Pnn := Make_Temporary (Loc, 'P');
5025 Make_Full_Type_Declaration (Loc,
5026 Defining_Identifier => Pnn,
5028 Make_Access_To_Object_Definition (Loc,
5029 All_Present => True,
5030 Subtype_Indication => New_Occurrence_Of (Typ, Loc))));
5034 Tnn := Make_Temporary (Loc, 'T');
5036 -- Create declaration for target of expression, and indicate that it
5037 -- does not require initialization.
5040 Make_Object_Declaration (Loc,
5041 Defining_Identifier => Tnn,
5042 Object_Definition => New_Occurrence_Of (Ttyp, Loc));
5043 Set_No_Initialization (Decl);
5044 Append_To (Actions, Decl);
5046 -- Now process the alternatives
5048 Alt := First (Alternatives (N));
5049 while Present (Alt) loop
5051 Aexp : Node_Id := Expression (Alt);
5052 Aloc : constant Source_Ptr := Sloc (Aexp);
5056 -- As described above, take Unrestricted_Access for case of non-
5057 -- scalar types, to avoid big copies, and special cases.
5059 if not Is_Elementary_Type (Typ) then
5061 Make_Attribute_Reference (Aloc,
5062 Prefix => Relocate_Node (Aexp),
5063 Attribute_Name => Name_Unrestricted_Access);
5067 Make_Assignment_Statement (Aloc,
5068 Name => New_Occurrence_Of (Tnn, Loc),
5069 Expression => Aexp));
5071 -- Propagate declarations inserted in the node by Insert_Actions
5072 -- (for example, temporaries generated to remove side effects).
5073 -- These actions must remain attached to the alternative, given
5074 -- that they are generated by the corresponding expression.
5076 if Present (Sinfo.Actions (Alt)) then
5077 Prepend_List (Sinfo.Actions (Alt), Stats);
5081 (Alternatives (Cstmt),
5082 Make_Case_Statement_Alternative (Sloc (Alt),
5083 Discrete_Choices => Discrete_Choices (Alt),
5084 Statements => Stats));
5090 Append_To (Actions, Cstmt);
5092 -- Construct and return final expression with actions
5094 if Is_Elementary_Type (Typ) then
5095 Fexp := New_Occurrence_Of (Tnn, Loc);
5098 Make_Explicit_Dereference (Loc,
5099 Prefix => New_Occurrence_Of (Tnn, Loc));
5103 Make_Expression_With_Actions (Loc,
5105 Actions => Actions));
5107 Analyze_And_Resolve (N, Typ);
5108 end Expand_N_Case_Expression;
5110 -----------------------------------
5111 -- Expand_N_Explicit_Dereference --
5112 -----------------------------------
5114 procedure Expand_N_Explicit_Dereference (N : Node_Id) is
5116 -- Insert explicit dereference call for the checked storage pool case
5118 Insert_Dereference_Action (Prefix (N));
5120 -- If the type is an Atomic type for which Atomic_Sync is enabled, then
5121 -- we set the atomic sync flag.
5123 if Is_Atomic (Etype (N))
5124 and then not Atomic_Synchronization_Disabled (Etype (N))
5126 Activate_Atomic_Synchronization (N);
5128 end Expand_N_Explicit_Dereference;
5130 --------------------------------------
5131 -- Expand_N_Expression_With_Actions --
5132 --------------------------------------
5134 procedure Expand_N_Expression_With_Actions (N : Node_Id) is
5136 function Process_Action (Act : Node_Id) return Traverse_Result;
5137 -- Inspect and process a single action of an expression_with_actions for
5138 -- transient controlled objects. If such objects are found, the routine
5139 -- generates code to clean them up when the context of the expression is
5140 -- evaluated or elaborated.
5142 --------------------
5143 -- Process_Action --
5144 --------------------
5146 function Process_Action (Act : Node_Id) return Traverse_Result is
5148 if Nkind (Act) = N_Object_Declaration
5149 and then Is_Finalizable_Transient (Act, N)
5151 Process_Transient_Object (Act, N);
5154 -- Avoid processing temporary function results multiple times when
5155 -- dealing with nested expression_with_actions.
5157 elsif Nkind (Act) = N_Expression_With_Actions then
5160 -- Do not process temporary function results in loops. This is done
5161 -- by Expand_N_Loop_Statement and Build_Finalizer.
5163 elsif Nkind (Act) = N_Loop_Statement then
5170 procedure Process_Single_Action is new Traverse_Proc (Process_Action);
5176 -- Start of processing for Expand_N_Expression_With_Actions
5179 -- Process the actions as described above
5181 Act := First (Actions (N));
5182 while Present (Act) loop
5183 Process_Single_Action (Act);
5187 -- Deal with case where there are no actions. In this case we simply
5188 -- rewrite the node with its expression since we don't need the actions
5189 -- and the specification of this node does not allow a null action list.
5191 -- Note: we use Rewrite instead of Replace, because Codepeer is using
5192 -- the expanded tree and relying on being able to retrieve the original
5193 -- tree in cases like this. This raises a whole lot of issues of whether
5194 -- we have problems elsewhere, which will be addressed in the future???
5196 if Is_Empty_List (Actions (N)) then
5197 Rewrite (N, Relocate_Node (Expression (N)));
5199 end Expand_N_Expression_With_Actions;
5201 ----------------------------
5202 -- Expand_N_If_Expression --
5203 ----------------------------
5205 -- Deal with limited types and condition actions
5207 procedure Expand_N_If_Expression (N : Node_Id) is
5208 procedure Process_Actions (Actions : List_Id);
5209 -- Inspect and process a single action list of an if expression for
5210 -- transient controlled objects. If such objects are found, the routine
5211 -- generates code to clean them up when the context of the expression is
5212 -- evaluated or elaborated.
5214 ---------------------
5215 -- Process_Actions --
5216 ---------------------
5218 procedure Process_Actions (Actions : List_Id) is
5222 Act := First (Actions);
5223 while Present (Act) loop
5224 if Nkind (Act) = N_Object_Declaration
5225 and then Is_Finalizable_Transient (Act, N)
5227 Process_Transient_Object (Act, N);
5232 end Process_Actions;
5236 Loc : constant Source_Ptr := Sloc (N);
5237 Cond : constant Node_Id := First (Expressions (N));
5238 Thenx : constant Node_Id := Next (Cond);
5239 Elsex : constant Node_Id := Next (Thenx);
5240 Typ : constant Entity_Id := Etype (N);
5248 Ptr_Typ : Entity_Id;
5250 -- Start of processing for Expand_N_If_Expression
5253 -- Check for MINIMIZED/ELIMINATED overflow mode
5255 if Minimized_Eliminated_Overflow_Check (N) then
5256 Apply_Arithmetic_Overflow_Check (N);
5260 -- Fold at compile time if condition known. We have already folded
5261 -- static if expressions, but it is possible to fold any case in which
5262 -- the condition is known at compile time, even though the result is
5265 -- Note that we don't do the fold of such cases in Sem_Elab because
5266 -- it can cause infinite loops with the expander adding a conditional
5267 -- expression, and Sem_Elab circuitry removing it repeatedly.
5269 if Compile_Time_Known_Value (Cond) then
5270 if Is_True (Expr_Value (Cond)) then
5272 Actions := Then_Actions (N);
5275 Actions := Else_Actions (N);
5280 if Present (Actions) then
5282 Make_Expression_With_Actions (Loc,
5283 Expression => Relocate_Node (Expr),
5284 Actions => Actions));
5285 Analyze_And_Resolve (N, Typ);
5287 Rewrite (N, Relocate_Node (Expr));
5290 -- Note that the result is never static (legitimate cases of static
5291 -- if expressions were folded in Sem_Eval).
5293 Set_Is_Static_Expression (N, False);
5297 -- If the type is limited, and the back end does not handle limited
5298 -- types, then we expand as follows to avoid the possibility of
5299 -- improper copying.
5301 -- type Ptr is access all Typ;
5305 -- Cnn := then-expr'Unrestricted_Access;
5308 -- Cnn := else-expr'Unrestricted_Access;
5311 -- and replace the if expression by a reference to Cnn.all.
5313 -- This special case can be skipped if the back end handles limited
5314 -- types properly and ensures that no incorrect copies are made.
5316 if Is_By_Reference_Type (Typ)
5317 and then not Back_End_Handles_Limited_Types
5319 -- When the "then" or "else" expressions involve controlled function
5320 -- calls, generated temporaries are chained on the corresponding list
5321 -- of actions. These temporaries need to be finalized after the if
5322 -- expression is evaluated.
5324 Process_Actions (Then_Actions (N));
5325 Process_Actions (Else_Actions (N));
5328 -- type Ann is access all Typ;
5330 Ptr_Typ := Make_Temporary (Loc, 'A');
5333 Make_Full_Type_Declaration (Loc,
5334 Defining_Identifier => Ptr_Typ,
5336 Make_Access_To_Object_Definition (Loc,
5337 All_Present => True,
5338 Subtype_Indication => New_Occurrence_Of (Typ, Loc))));
5343 Cnn := Make_Temporary (Loc, 'C', N);
5346 Make_Object_Declaration (Loc,
5347 Defining_Identifier => Cnn,
5348 Object_Definition => New_Occurrence_Of (Ptr_Typ, Loc));
5352 -- Cnn := <Thenx>'Unrestricted_Access;
5354 -- Cnn := <Elsex>'Unrestricted_Access;
5358 Make_Implicit_If_Statement (N,
5359 Condition => Relocate_Node (Cond),
5360 Then_Statements => New_List (
5361 Make_Assignment_Statement (Sloc (Thenx),
5362 Name => New_Occurrence_Of (Cnn, Sloc (Thenx)),
5364 Make_Attribute_Reference (Loc,
5365 Prefix => Relocate_Node (Thenx),
5366 Attribute_Name => Name_Unrestricted_Access))),
5368 Else_Statements => New_List (
5369 Make_Assignment_Statement (Sloc (Elsex),
5370 Name => New_Occurrence_Of (Cnn, Sloc (Elsex)),
5372 Make_Attribute_Reference (Loc,
5373 Prefix => Relocate_Node (Elsex),
5374 Attribute_Name => Name_Unrestricted_Access))));
5376 -- Preserve the original context for which the if statement is being
5377 -- generated. This is needed by the finalization machinery to prevent
5378 -- the premature finalization of controlled objects found within the
5381 Set_From_Conditional_Expression (New_If);
5384 Make_Explicit_Dereference (Loc,
5385 Prefix => New_Occurrence_Of (Cnn, Loc));
5387 -- If the result is an unconstrained array and the if expression is in a
5388 -- context other than the initializing expression of the declaration of
5389 -- an object, then we pull out the if expression as follows:
5391 -- Cnn : constant typ := if-expression
5393 -- and then replace the if expression with an occurrence of Cnn. This
5394 -- avoids the need in the back end to create on-the-fly variable length
5395 -- temporaries (which it cannot do!)
5397 -- Note that the test for being in an object declaration avoids doing an
5398 -- unnecessary expansion, and also avoids infinite recursion.
5400 elsif Is_Array_Type (Typ) and then not Is_Constrained (Typ)
5401 and then (Nkind (Parent (N)) /= N_Object_Declaration
5402 or else Expression (Parent (N)) /= N)
5405 Cnn : constant Node_Id := Make_Temporary (Loc, 'C', N);
5408 Make_Object_Declaration (Loc,
5409 Defining_Identifier => Cnn,
5410 Constant_Present => True,
5411 Object_Definition => New_Occurrence_Of (Typ, Loc),
5412 Expression => Relocate_Node (N),
5413 Has_Init_Expression => True));
5415 Rewrite (N, New_Occurrence_Of (Cnn, Loc));
5419 -- For other types, we only need to expand if there are other actions
5420 -- associated with either branch.
5422 elsif Present (Then_Actions (N)) or else Present (Else_Actions (N)) then
5424 -- We now wrap the actions into the appropriate expression
5426 if Present (Then_Actions (N)) then
5428 Make_Expression_With_Actions (Sloc (Thenx),
5429 Actions => Then_Actions (N),
5430 Expression => Relocate_Node (Thenx)));
5432 Set_Then_Actions (N, No_List);
5433 Analyze_And_Resolve (Thenx, Typ);
5436 if Present (Else_Actions (N)) then
5438 Make_Expression_With_Actions (Sloc (Elsex),
5439 Actions => Else_Actions (N),
5440 Expression => Relocate_Node (Elsex)));
5442 Set_Else_Actions (N, No_List);
5443 Analyze_And_Resolve (Elsex, Typ);
5448 -- If no actions then no expansion needed, gigi will handle it using the
5449 -- same approach as a C conditional expression.
5455 -- Fall through here for either the limited expansion, or the case of
5456 -- inserting actions for non-limited types. In both these cases, we must
5457 -- move the SLOC of the parent If statement to the newly created one and
5458 -- change it to the SLOC of the expression which, after expansion, will
5459 -- correspond to what is being evaluated.
5461 if Present (Parent (N)) and then Nkind (Parent (N)) = N_If_Statement then
5462 Set_Sloc (New_If, Sloc (Parent (N)));
5463 Set_Sloc (Parent (N), Loc);
5466 -- Make sure Then_Actions and Else_Actions are appropriately moved
5467 -- to the new if statement.
5469 if Present (Then_Actions (N)) then
5471 (First (Then_Statements (New_If)), Then_Actions (N));
5474 if Present (Else_Actions (N)) then
5476 (First (Else_Statements (New_If)), Else_Actions (N));
5479 Insert_Action (N, Decl);
5480 Insert_Action (N, New_If);
5482 Analyze_And_Resolve (N, Typ);
5483 end Expand_N_If_Expression;
5489 procedure Expand_N_In (N : Node_Id) is
5490 Loc : constant Source_Ptr := Sloc (N);
5491 Restyp : constant Entity_Id := Etype (N);
5492 Lop : constant Node_Id := Left_Opnd (N);
5493 Rop : constant Node_Id := Right_Opnd (N);
5494 Static : constant Boolean := Is_OK_Static_Expression (N);
5499 procedure Substitute_Valid_Check;
5500 -- Replaces node N by Lop'Valid. This is done when we have an explicit
5501 -- test for the left operand being in range of its subtype.
5503 ----------------------------
5504 -- Substitute_Valid_Check --
5505 ----------------------------
5507 procedure Substitute_Valid_Check is
5510 Make_Attribute_Reference (Loc,
5511 Prefix => Relocate_Node (Lop),
5512 Attribute_Name => Name_Valid));
5514 Analyze_And_Resolve (N, Restyp);
5516 -- Give warning unless overflow checking is MINIMIZED or ELIMINATED,
5517 -- in which case, this usage makes sense, and in any case, we have
5518 -- actually eliminated the danger of optimization above.
5520 if Overflow_Check_Mode not in Minimized_Or_Eliminated then
5522 ("??explicit membership test may be optimized away", N);
5523 Error_Msg_N -- CODEFIX
5524 ("\??use ''Valid attribute instead", N);
5528 end Substitute_Valid_Check;
5530 -- Start of processing for Expand_N_In
5533 -- If set membership case, expand with separate procedure
5535 if Present (Alternatives (N)) then
5536 Expand_Set_Membership (N);
5540 -- Not set membership, proceed with expansion
5542 Ltyp := Etype (Left_Opnd (N));
5543 Rtyp := Etype (Right_Opnd (N));
5545 -- If MINIMIZED/ELIMINATED overflow mode and type is a signed integer
5546 -- type, then expand with a separate procedure. Note the use of the
5547 -- flag No_Minimize_Eliminate to prevent infinite recursion.
5549 if Overflow_Check_Mode in Minimized_Or_Eliminated
5550 and then Is_Signed_Integer_Type (Ltyp)
5551 and then not No_Minimize_Eliminate (N)
5553 Expand_Membership_Minimize_Eliminate_Overflow (N);
5557 -- Check case of explicit test for an expression in range of its
5558 -- subtype. This is suspicious usage and we replace it with a 'Valid
5559 -- test and give a warning for scalar types.
5561 if Is_Scalar_Type (Ltyp)
5563 -- Only relevant for source comparisons
5565 and then Comes_From_Source (N)
5567 -- In floating-point this is a standard way to check for finite values
5568 -- and using 'Valid would typically be a pessimization.
5570 and then not Is_Floating_Point_Type (Ltyp)
5572 -- Don't give the message unless right operand is a type entity and
5573 -- the type of the left operand matches this type. Note that this
5574 -- eliminates the cases where MINIMIZED/ELIMINATED mode overflow
5575 -- checks have changed the type of the left operand.
5577 and then Nkind (Rop) in N_Has_Entity
5578 and then Ltyp = Entity (Rop)
5580 -- Skip in VM mode, where we have no sense of invalid values. The
5581 -- warning still seems relevant, but not important enough to worry.
5583 and then VM_Target = No_VM
5585 -- Skip this for predicated types, where such expressions are a
5586 -- reasonable way of testing if something meets the predicate.
5588 and then not Present (Predicate_Function (Ltyp))
5590 Substitute_Valid_Check;
5594 -- Do validity check on operands
5596 if Validity_Checks_On and Validity_Check_Operands then
5597 Ensure_Valid (Left_Opnd (N));
5598 Validity_Check_Range (Right_Opnd (N));
5601 -- Case of explicit range
5603 if Nkind (Rop) = N_Range then
5605 Lo : constant Node_Id := Low_Bound (Rop);
5606 Hi : constant Node_Id := High_Bound (Rop);
5608 Lo_Orig : constant Node_Id := Original_Node (Lo);
5609 Hi_Orig : constant Node_Id := Original_Node (Hi);
5611 Lcheck : Compare_Result;
5612 Ucheck : Compare_Result;
5614 Warn1 : constant Boolean :=
5615 Constant_Condition_Warnings
5616 and then Comes_From_Source (N)
5617 and then not In_Instance;
5618 -- This must be true for any of the optimization warnings, we
5619 -- clearly want to give them only for source with the flag on. We
5620 -- also skip these warnings in an instance since it may be the
5621 -- case that different instantiations have different ranges.
5623 Warn2 : constant Boolean :=
5625 and then Nkind (Original_Node (Rop)) = N_Range
5626 and then Is_Integer_Type (Etype (Lo));
5627 -- For the case where only one bound warning is elided, we also
5628 -- insist on an explicit range and an integer type. The reason is
5629 -- that the use of enumeration ranges including an end point is
5630 -- common, as is the use of a subtype name, one of whose bounds is
5631 -- the same as the type of the expression.
5634 -- If test is explicit x'First .. x'Last, replace by valid check
5636 -- Could use some individual comments for this complex test ???
5638 if Is_Scalar_Type (Ltyp)
5640 -- And left operand is X'First where X matches left operand
5641 -- type (this eliminates cases of type mismatch, including
5642 -- the cases where ELIMINATED/MINIMIZED mode has changed the
5643 -- type of the left operand.
5645 and then Nkind (Lo_Orig) = N_Attribute_Reference
5646 and then Attribute_Name (Lo_Orig) = Name_First
5647 and then Nkind (Prefix (Lo_Orig)) in N_Has_Entity
5648 and then Entity (Prefix (Lo_Orig)) = Ltyp
5650 -- Same tests for right operand
5652 and then Nkind (Hi_Orig) = N_Attribute_Reference
5653 and then Attribute_Name (Hi_Orig) = Name_Last
5654 and then Nkind (Prefix (Hi_Orig)) in N_Has_Entity
5655 and then Entity (Prefix (Hi_Orig)) = Ltyp
5657 -- Relevant only for source cases
5659 and then Comes_From_Source (N)
5661 -- Omit for VM cases, where we don't have invalid values
5663 and then VM_Target = No_VM
5665 Substitute_Valid_Check;
5669 -- If bounds of type are known at compile time, and the end points
5670 -- are known at compile time and identical, this is another case
5671 -- for substituting a valid test. We only do this for discrete
5672 -- types, since it won't arise in practice for float types.
5674 if Comes_From_Source (N)
5675 and then Is_Discrete_Type (Ltyp)
5676 and then Compile_Time_Known_Value (Type_High_Bound (Ltyp))
5677 and then Compile_Time_Known_Value (Type_Low_Bound (Ltyp))
5678 and then Compile_Time_Known_Value (Lo)
5679 and then Compile_Time_Known_Value (Hi)
5680 and then Expr_Value (Type_High_Bound (Ltyp)) = Expr_Value (Hi)
5681 and then Expr_Value (Type_Low_Bound (Ltyp)) = Expr_Value (Lo)
5683 -- Kill warnings in instances, since they may be cases where we
5684 -- have a test in the generic that makes sense with some types
5685 -- and not with other types.
5687 and then not In_Instance
5689 Substitute_Valid_Check;
5693 -- If we have an explicit range, do a bit of optimization based on
5694 -- range analysis (we may be able to kill one or both checks).
5696 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => False);
5697 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => False);
5699 -- If either check is known to fail, replace result by False since
5700 -- the other check does not matter. Preserve the static flag for
5701 -- legality checks, because we are constant-folding beyond RM 4.9.
5703 if Lcheck = LT or else Ucheck = GT then
5705 Error_Msg_N ("?c?range test optimized away", N);
5706 Error_Msg_N ("\?c?value is known to be out of range", N);
5709 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
5710 Analyze_And_Resolve (N, Restyp);
5711 Set_Is_Static_Expression (N, Static);
5714 -- If both checks are known to succeed, replace result by True,
5715 -- since we know we are in range.
5717 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
5719 Error_Msg_N ("?c?range test optimized away", N);
5720 Error_Msg_N ("\?c?value is known to be in range", N);
5723 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
5724 Analyze_And_Resolve (N, Restyp);
5725 Set_Is_Static_Expression (N, Static);
5728 -- If lower bound check succeeds and upper bound check is not
5729 -- known to succeed or fail, then replace the range check with
5730 -- a comparison against the upper bound.
5732 elsif Lcheck in Compare_GE then
5733 if Warn2 and then not In_Instance then
5734 Error_Msg_N ("??lower bound test optimized away", Lo);
5735 Error_Msg_N ("\??value is known to be in range", Lo);
5741 Right_Opnd => High_Bound (Rop)));
5742 Analyze_And_Resolve (N, Restyp);
5745 -- If upper bound check succeeds and lower bound check is not
5746 -- known to succeed or fail, then replace the range check with
5747 -- a comparison against the lower bound.
5749 elsif Ucheck in Compare_LE then
5750 if Warn2 and then not In_Instance then
5751 Error_Msg_N ("??upper bound test optimized away", Hi);
5752 Error_Msg_N ("\??value is known to be in range", Hi);
5758 Right_Opnd => Low_Bound (Rop)));
5759 Analyze_And_Resolve (N, Restyp);
5763 -- We couldn't optimize away the range check, but there is one
5764 -- more issue. If we are checking constant conditionals, then we
5765 -- see if we can determine the outcome assuming everything is
5766 -- valid, and if so give an appropriate warning.
5768 if Warn1 and then not Assume_No_Invalid_Values then
5769 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => True);
5770 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => True);
5772 -- Result is out of range for valid value
5774 if Lcheck = LT or else Ucheck = GT then
5776 ("?c?value can only be in range if it is invalid", N);
5778 -- Result is in range for valid value
5780 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
5782 ("?c?value can only be out of range if it is invalid", N);
5784 -- Lower bound check succeeds if value is valid
5786 elsif Warn2 and then Lcheck in Compare_GE then
5788 ("?c?lower bound check only fails if it is invalid", Lo);
5790 -- Upper bound check succeeds if value is valid
5792 elsif Warn2 and then Ucheck in Compare_LE then
5794 ("?c?upper bound check only fails for invalid values", Hi);
5799 -- For all other cases of an explicit range, nothing to be done
5803 -- Here right operand is a subtype mark
5807 Typ : Entity_Id := Etype (Rop);
5808 Is_Acc : constant Boolean := Is_Access_Type (Typ);
5809 Cond : Node_Id := Empty;
5811 Obj : Node_Id := Lop;
5812 SCIL_Node : Node_Id;
5815 Remove_Side_Effects (Obj);
5817 -- For tagged type, do tagged membership operation
5819 if Is_Tagged_Type (Typ) then
5821 -- No expansion will be performed when VM_Target, as the VM
5822 -- back-ends will handle the membership tests directly (tags
5823 -- are not explicitly represented in Java objects, so the
5824 -- normal tagged membership expansion is not what we want).
5826 if Tagged_Type_Expansion then
5827 Tagged_Membership (N, SCIL_Node, New_N);
5829 Analyze_And_Resolve (N, Restyp);
5831 -- Update decoration of relocated node referenced by the
5834 if Generate_SCIL and then Present (SCIL_Node) then
5835 Set_SCIL_Node (N, SCIL_Node);
5841 -- If type is scalar type, rewrite as x in t'First .. t'Last.
5842 -- This reason we do this is that the bounds may have the wrong
5843 -- type if they come from the original type definition. Also this
5844 -- way we get all the processing above for an explicit range.
5846 -- Don't do this for predicated types, since in this case we
5847 -- want to check the predicate.
5849 elsif Is_Scalar_Type (Typ) then
5850 if No (Predicate_Function (Typ)) then
5854 Make_Attribute_Reference (Loc,
5855 Attribute_Name => Name_First,
5856 Prefix => New_Occurrence_Of (Typ, Loc)),
5859 Make_Attribute_Reference (Loc,
5860 Attribute_Name => Name_Last,
5861 Prefix => New_Occurrence_Of (Typ, Loc))));
5862 Analyze_And_Resolve (N, Restyp);
5867 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
5868 -- a membership test if the subtype mark denotes a constrained
5869 -- Unchecked_Union subtype and the expression lacks inferable
5872 elsif Is_Unchecked_Union (Base_Type (Typ))
5873 and then Is_Constrained (Typ)
5874 and then not Has_Inferable_Discriminants (Lop)
5877 Make_Raise_Program_Error (Loc,
5878 Reason => PE_Unchecked_Union_Restriction));
5880 -- Prevent Gigi from generating incorrect code by rewriting the
5881 -- test as False. What is this undocumented thing about ???
5883 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
5887 -- Here we have a non-scalar type
5890 Typ := Designated_Type (Typ);
5893 if not Is_Constrained (Typ) then
5894 Rewrite (N, New_Occurrence_Of (Standard_True, Loc));
5895 Analyze_And_Resolve (N, Restyp);
5897 -- For the constrained array case, we have to check the subscripts
5898 -- for an exact match if the lengths are non-zero (the lengths
5899 -- must match in any case).
5901 elsif Is_Array_Type (Typ) then
5902 Check_Subscripts : declare
5903 function Build_Attribute_Reference
5906 Dim : Nat) return Node_Id;
5907 -- Build attribute reference E'Nam (Dim)
5909 -------------------------------
5910 -- Build_Attribute_Reference --
5911 -------------------------------
5913 function Build_Attribute_Reference
5916 Dim : Nat) return Node_Id
5920 Make_Attribute_Reference (Loc,
5922 Attribute_Name => Nam,
5923 Expressions => New_List (
5924 Make_Integer_Literal (Loc, Dim)));
5925 end Build_Attribute_Reference;
5927 -- Start of processing for Check_Subscripts
5930 for J in 1 .. Number_Dimensions (Typ) loop
5931 Evolve_And_Then (Cond,
5934 Build_Attribute_Reference
5935 (Duplicate_Subexpr_No_Checks (Obj),
5938 Build_Attribute_Reference
5939 (New_Occurrence_Of (Typ, Loc), Name_First, J)));
5941 Evolve_And_Then (Cond,
5944 Build_Attribute_Reference
5945 (Duplicate_Subexpr_No_Checks (Obj),
5948 Build_Attribute_Reference
5949 (New_Occurrence_Of (Typ, Loc), Name_Last, J)));
5958 Right_Opnd => Make_Null (Loc)),
5959 Right_Opnd => Cond);
5963 Analyze_And_Resolve (N, Restyp);
5964 end Check_Subscripts;
5966 -- These are the cases where constraint checks may be required,
5967 -- e.g. records with possible discriminants
5970 -- Expand the test into a series of discriminant comparisons.
5971 -- The expression that is built is the negation of the one that
5972 -- is used for checking discriminant constraints.
5974 Obj := Relocate_Node (Left_Opnd (N));
5976 if Has_Discriminants (Typ) then
5977 Cond := Make_Op_Not (Loc,
5978 Right_Opnd => Build_Discriminant_Checks (Obj, Typ));
5981 Cond := Make_Or_Else (Loc,
5985 Right_Opnd => Make_Null (Loc)),
5986 Right_Opnd => Cond);
5990 Cond := New_Occurrence_Of (Standard_True, Loc);
5994 Analyze_And_Resolve (N, Restyp);
5997 -- Ada 2012 (AI05-0149): Handle membership tests applied to an
5998 -- expression of an anonymous access type. This can involve an
5999 -- accessibility test and a tagged type membership test in the
6000 -- case of tagged designated types.
6002 if Ada_Version >= Ada_2012
6004 and then Ekind (Ltyp) = E_Anonymous_Access_Type
6007 Expr_Entity : Entity_Id := Empty;
6009 Param_Level : Node_Id;
6010 Type_Level : Node_Id;
6013 if Is_Entity_Name (Lop) then
6014 Expr_Entity := Param_Entity (Lop);
6016 if not Present (Expr_Entity) then
6017 Expr_Entity := Entity (Lop);
6021 -- If a conversion of the anonymous access value to the
6022 -- tested type would be illegal, then the result is False.
6024 if not Valid_Conversion
6025 (Lop, Rtyp, Lop, Report_Errs => False)
6027 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
6028 Analyze_And_Resolve (N, Restyp);
6030 -- Apply an accessibility check if the access object has an
6031 -- associated access level and when the level of the type is
6032 -- less deep than the level of the access parameter. This
6033 -- only occur for access parameters and stand-alone objects
6034 -- of an anonymous access type.
6037 if Present (Expr_Entity)
6040 (Effective_Extra_Accessibility (Expr_Entity))
6041 and then UI_Gt (Object_Access_Level (Lop),
6042 Type_Access_Level (Rtyp))
6046 (Effective_Extra_Accessibility (Expr_Entity), Loc);
6049 Make_Integer_Literal (Loc, Type_Access_Level (Rtyp));
6051 -- Return True only if the accessibility level of the
6052 -- expression entity is not deeper than the level of
6053 -- the tested access type.
6057 Left_Opnd => Relocate_Node (N),
6058 Right_Opnd => Make_Op_Le (Loc,
6059 Left_Opnd => Param_Level,
6060 Right_Opnd => Type_Level)));
6062 Analyze_And_Resolve (N);
6065 -- If the designated type is tagged, do tagged membership
6068 -- *** NOTE: we have to check not null before doing the
6069 -- tagged membership test (but maybe that can be done
6070 -- inside Tagged_Membership?).
6072 if Is_Tagged_Type (Typ) then
6075 Left_Opnd => Relocate_Node (N),
6079 Right_Opnd => Make_Null (Loc))));
6081 -- No expansion will be performed when VM_Target, as
6082 -- the VM back-ends will handle the membership tests
6083 -- directly (tags are not explicitly represented in
6084 -- Java objects, so the normal tagged membership
6085 -- expansion is not what we want).
6087 if Tagged_Type_Expansion then
6089 -- Note that we have to pass Original_Node, because
6090 -- the membership test might already have been
6091 -- rewritten by earlier parts of membership test.
6094 (Original_Node (N), SCIL_Node, New_N);
6096 -- Update decoration of relocated node referenced
6097 -- by the SCIL node.
6099 if Generate_SCIL and then Present (SCIL_Node) then
6100 Set_SCIL_Node (New_N, SCIL_Node);
6105 Left_Opnd => Relocate_Node (N),
6106 Right_Opnd => New_N));
6108 Analyze_And_Resolve (N, Restyp);
6117 -- At this point, we have done the processing required for the basic
6118 -- membership test, but not yet dealt with the predicate.
6122 -- If a predicate is present, then we do the predicate test, but we
6123 -- most certainly want to omit this if we are within the predicate
6124 -- function itself, since otherwise we have an infinite recursion.
6125 -- The check should also not be emitted when testing against a range
6126 -- (the check is only done when the right operand is a subtype; see
6127 -- RM12-4.5.2 (28.1/3-30/3)).
6130 PFunc : constant Entity_Id := Predicate_Function (Rtyp);
6134 and then Current_Scope /= PFunc
6135 and then Nkind (Rop) /= N_Range
6139 Left_Opnd => Relocate_Node (N),
6140 Right_Opnd => Make_Predicate_Call (Rtyp, Lop, Mem => True)));
6142 -- Analyze new expression, mark left operand as analyzed to
6143 -- avoid infinite recursion adding predicate calls. Similarly,
6144 -- suppress further range checks on the call.
6146 Set_Analyzed (Left_Opnd (N));
6147 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
6149 -- All done, skip attempt at compile time determination of result
6156 --------------------------------
6157 -- Expand_N_Indexed_Component --
6158 --------------------------------
6160 procedure Expand_N_Indexed_Component (N : Node_Id) is
6161 Loc : constant Source_Ptr := Sloc (N);
6162 Typ : constant Entity_Id := Etype (N);
6163 P : constant Node_Id := Prefix (N);
6164 T : constant Entity_Id := Etype (P);
6168 -- A special optimization, if we have an indexed component that is
6169 -- selecting from a slice, then we can eliminate the slice, since, for
6170 -- example, x (i .. j)(k) is identical to x(k). The only difference is
6171 -- the range check required by the slice. The range check for the slice
6172 -- itself has already been generated. The range check for the
6173 -- subscripting operation is ensured by converting the subject to
6174 -- the subtype of the slice.
6176 -- This optimization not only generates better code, avoiding slice
6177 -- messing especially in the packed case, but more importantly bypasses
6178 -- some problems in handling this peculiar case, for example, the issue
6179 -- of dealing specially with object renamings.
6181 if Nkind (P) = N_Slice
6183 -- This optimization is disabled for CodePeer because it can transform
6184 -- an index-check constraint_error into a range-check constraint_error
6185 -- and CodePeer cares about that distinction.
6187 and then not CodePeer_Mode
6190 Make_Indexed_Component (Loc,
6191 Prefix => Prefix (P),
6192 Expressions => New_List (
6194 (Etype (First_Index (Etype (P))),
6195 First (Expressions (N))))));
6196 Analyze_And_Resolve (N, Typ);
6200 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
6201 -- function, then additional actuals must be passed.
6203 if Ada_Version >= Ada_2005
6204 and then Is_Build_In_Place_Function_Call (P)
6206 Make_Build_In_Place_Call_In_Anonymous_Context (P);
6209 -- If the prefix is an access type, then we unconditionally rewrite if
6210 -- as an explicit dereference. This simplifies processing for several
6211 -- cases, including packed array cases and certain cases in which checks
6212 -- must be generated. We used to try to do this only when it was
6213 -- necessary, but it cleans up the code to do it all the time.
6215 if Is_Access_Type (T) then
6216 Insert_Explicit_Dereference (P);
6217 Analyze_And_Resolve (P, Designated_Type (T));
6218 Atp := Designated_Type (T);
6223 -- Generate index and validity checks
6225 Generate_Index_Checks (N);
6227 if Validity_Checks_On and then Validity_Check_Subscripts then
6228 Apply_Subscript_Validity_Checks (N);
6231 -- If selecting from an array with atomic components, and atomic sync
6232 -- is not suppressed for this array type, set atomic sync flag.
6234 if (Has_Atomic_Components (Atp)
6235 and then not Atomic_Synchronization_Disabled (Atp))
6236 or else (Is_Atomic (Typ)
6237 and then not Atomic_Synchronization_Disabled (Typ))
6239 Activate_Atomic_Synchronization (N);
6242 -- All done for the non-packed case
6244 if not Is_Packed (Etype (Prefix (N))) then
6248 -- For packed arrays that are not bit-packed (i.e. the case of an array
6249 -- with one or more index types with a non-contiguous enumeration type),
6250 -- we can always use the normal packed element get circuit.
6252 if not Is_Bit_Packed_Array (Etype (Prefix (N))) then
6253 Expand_Packed_Element_Reference (N);
6257 -- For a reference to a component of a bit packed array, we convert it
6258 -- to a reference to the corresponding Packed_Array_Impl_Type. We only
6259 -- want to do this for simple references, and not for:
6261 -- Left side of assignment, or prefix of left side of assignment, or
6262 -- prefix of the prefix, to handle packed arrays of packed arrays,
6263 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
6265 -- Renaming objects in renaming associations
6266 -- This case is handled when a use of the renamed variable occurs
6268 -- Actual parameters for a procedure call
6269 -- This case is handled in Exp_Ch6.Expand_Actuals
6271 -- The second expression in a 'Read attribute reference
6273 -- The prefix of an address or bit or size attribute reference
6275 -- The following circuit detects these exceptions
6278 Child : Node_Id := N;
6279 Parnt : Node_Id := Parent (N);
6283 if Nkind (Parnt) = N_Unchecked_Expression then
6286 elsif Nkind_In (Parnt, N_Object_Renaming_Declaration,
6287 N_Procedure_Call_Statement)
6288 or else (Nkind (Parnt) = N_Parameter_Association
6290 Nkind (Parent (Parnt)) = N_Procedure_Call_Statement)
6294 elsif Nkind (Parnt) = N_Attribute_Reference
6295 and then Nam_In (Attribute_Name (Parnt), Name_Address,
6298 and then Prefix (Parnt) = Child
6302 elsif Nkind (Parnt) = N_Assignment_Statement
6303 and then Name (Parnt) = Child
6307 -- If the expression is an index of an indexed component, it must
6308 -- be expanded regardless of context.
6310 elsif Nkind (Parnt) = N_Indexed_Component
6311 and then Child /= Prefix (Parnt)
6313 Expand_Packed_Element_Reference (N);
6316 elsif Nkind (Parent (Parnt)) = N_Assignment_Statement
6317 and then Name (Parent (Parnt)) = Parnt
6321 elsif Nkind (Parnt) = N_Attribute_Reference
6322 and then Attribute_Name (Parnt) = Name_Read
6323 and then Next (First (Expressions (Parnt))) = Child
6327 elsif Nkind_In (Parnt, N_Indexed_Component, N_Selected_Component)
6328 and then Prefix (Parnt) = Child
6333 Expand_Packed_Element_Reference (N);
6337 -- Keep looking up tree for unchecked expression, or if we are the
6338 -- prefix of a possible assignment left side.
6341 Parnt := Parent (Child);
6344 end Expand_N_Indexed_Component;
6346 ---------------------
6347 -- Expand_N_Not_In --
6348 ---------------------
6350 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
6351 -- can be done. This avoids needing to duplicate this expansion code.
6353 procedure Expand_N_Not_In (N : Node_Id) is
6354 Loc : constant Source_Ptr := Sloc (N);
6355 Typ : constant Entity_Id := Etype (N);
6356 Cfs : constant Boolean := Comes_From_Source (N);
6363 Left_Opnd => Left_Opnd (N),
6364 Right_Opnd => Right_Opnd (N))));
6366 -- If this is a set membership, preserve list of alternatives
6368 Set_Alternatives (Right_Opnd (N), Alternatives (Original_Node (N)));
6370 -- We want this to appear as coming from source if original does (see
6371 -- transformations in Expand_N_In).
6373 Set_Comes_From_Source (N, Cfs);
6374 Set_Comes_From_Source (Right_Opnd (N), Cfs);
6376 -- Now analyze transformed node
6378 Analyze_And_Resolve (N, Typ);
6379 end Expand_N_Not_In;
6385 -- The only replacement required is for the case of a null of a type that
6386 -- is an access to protected subprogram, or a subtype thereof. We represent
6387 -- such access values as a record, and so we must replace the occurrence of
6388 -- null by the equivalent record (with a null address and a null pointer in
6389 -- it), so that the backend creates the proper value.
6391 procedure Expand_N_Null (N : Node_Id) is
6392 Loc : constant Source_Ptr := Sloc (N);
6393 Typ : constant Entity_Id := Base_Type (Etype (N));
6397 if Is_Access_Protected_Subprogram_Type (Typ) then
6399 Make_Aggregate (Loc,
6400 Expressions => New_List (
6401 New_Occurrence_Of (RTE (RE_Null_Address), Loc),
6405 Analyze_And_Resolve (N, Equivalent_Type (Typ));
6407 -- For subsequent semantic analysis, the node must retain its type.
6408 -- Gigi in any case replaces this type by the corresponding record
6409 -- type before processing the node.
6415 when RE_Not_Available =>
6419 ---------------------
6420 -- Expand_N_Op_Abs --
6421 ---------------------
6423 procedure Expand_N_Op_Abs (N : Node_Id) is
6424 Loc : constant Source_Ptr := Sloc (N);
6425 Expr : constant Node_Id := Right_Opnd (N);
6428 Unary_Op_Validity_Checks (N);
6430 -- Check for MINIMIZED/ELIMINATED overflow mode
6432 if Minimized_Eliminated_Overflow_Check (N) then
6433 Apply_Arithmetic_Overflow_Check (N);
6437 -- Deal with software overflow checking
6439 if not Backend_Overflow_Checks_On_Target
6440 and then Is_Signed_Integer_Type (Etype (N))
6441 and then Do_Overflow_Check (N)
6443 -- The only case to worry about is when the argument is equal to the
6444 -- largest negative number, so what we do is to insert the check:
6446 -- [constraint_error when Expr = typ'Base'First]
6448 -- with the usual Duplicate_Subexpr use coding for expr
6451 Make_Raise_Constraint_Error (Loc,
6454 Left_Opnd => Duplicate_Subexpr (Expr),
6456 Make_Attribute_Reference (Loc,
6458 New_Occurrence_Of (Base_Type (Etype (Expr)), Loc),
6459 Attribute_Name => Name_First)),
6460 Reason => CE_Overflow_Check_Failed));
6462 end Expand_N_Op_Abs;
6464 ---------------------
6465 -- Expand_N_Op_Add --
6466 ---------------------
6468 procedure Expand_N_Op_Add (N : Node_Id) is
6469 Typ : constant Entity_Id := Etype (N);
6472 Binary_Op_Validity_Checks (N);
6474 -- Check for MINIMIZED/ELIMINATED overflow mode
6476 if Minimized_Eliminated_Overflow_Check (N) then
6477 Apply_Arithmetic_Overflow_Check (N);
6481 -- N + 0 = 0 + N = N for integer types
6483 if Is_Integer_Type (Typ) then
6484 if Compile_Time_Known_Value (Right_Opnd (N))
6485 and then Expr_Value (Right_Opnd (N)) = Uint_0
6487 Rewrite (N, Left_Opnd (N));
6490 elsif Compile_Time_Known_Value (Left_Opnd (N))
6491 and then Expr_Value (Left_Opnd (N)) = Uint_0
6493 Rewrite (N, Right_Opnd (N));
6498 -- Arithmetic overflow checks for signed integer/fixed point types
6500 if Is_Signed_Integer_Type (Typ) or else Is_Fixed_Point_Type (Typ) then
6501 Apply_Arithmetic_Overflow_Check (N);
6505 -- Overflow checks for floating-point if -gnateF mode active
6507 Check_Float_Op_Overflow (N);
6508 end Expand_N_Op_Add;
6510 ---------------------
6511 -- Expand_N_Op_And --
6512 ---------------------
6514 procedure Expand_N_Op_And (N : Node_Id) is
6515 Typ : constant Entity_Id := Etype (N);
6518 Binary_Op_Validity_Checks (N);
6520 if Is_Array_Type (Etype (N)) then
6521 Expand_Boolean_Operator (N);
6523 elsif Is_Boolean_Type (Etype (N)) then
6524 Adjust_Condition (Left_Opnd (N));
6525 Adjust_Condition (Right_Opnd (N));
6526 Set_Etype (N, Standard_Boolean);
6527 Adjust_Result_Type (N, Typ);
6529 elsif Is_Intrinsic_Subprogram (Entity (N)) then
6530 Expand_Intrinsic_Call (N, Entity (N));
6533 end Expand_N_Op_And;
6535 ------------------------
6536 -- Expand_N_Op_Concat --
6537 ------------------------
6539 procedure Expand_N_Op_Concat (N : Node_Id) is
6541 -- List of operands to be concatenated
6544 -- Node which is to be replaced by the result of concatenating the nodes
6545 -- in the list Opnds.
6548 -- Ensure validity of both operands
6550 Binary_Op_Validity_Checks (N);
6552 -- If we are the left operand of a concatenation higher up the tree,
6553 -- then do nothing for now, since we want to deal with a series of
6554 -- concatenations as a unit.
6556 if Nkind (Parent (N)) = N_Op_Concat
6557 and then N = Left_Opnd (Parent (N))
6562 -- We get here with a concatenation whose left operand may be a
6563 -- concatenation itself with a consistent type. We need to process
6564 -- these concatenation operands from left to right, which means
6565 -- from the deepest node in the tree to the highest node.
6568 while Nkind (Left_Opnd (Cnode)) = N_Op_Concat loop
6569 Cnode := Left_Opnd (Cnode);
6572 -- Now Cnode is the deepest concatenation, and its parents are the
6573 -- concatenation nodes above, so now we process bottom up, doing the
6576 -- The outer loop runs more than once if more than one concatenation
6577 -- type is involved.
6580 Opnds := New_List (Left_Opnd (Cnode), Right_Opnd (Cnode));
6581 Set_Parent (Opnds, N);
6583 -- The inner loop gathers concatenation operands
6585 Inner : while Cnode /= N
6586 and then Base_Type (Etype (Cnode)) =
6587 Base_Type (Etype (Parent (Cnode)))
6589 Cnode := Parent (Cnode);
6590 Append (Right_Opnd (Cnode), Opnds);
6593 -- Note: The following code is a temporary workaround for N731-034
6594 -- and N829-028 and will be kept until the general issue of internal
6595 -- symbol serialization is addressed. The workaround is kept under a
6596 -- debug switch to avoid permiating into the general case.
6598 -- Wrap the node to concatenate into an expression actions node to
6599 -- keep it nicely packaged. This is useful in the case of an assert
6600 -- pragma with a concatenation where we want to be able to delete
6601 -- the concatenation and all its expansion stuff.
6603 if Debug_Flag_Dot_H then
6605 Cnod : constant Node_Id := Relocate_Node (Cnode);
6606 Typ : constant Entity_Id := Base_Type (Etype (Cnode));
6609 -- Note: use Rewrite rather than Replace here, so that for
6610 -- example Why_Not_Static can find the original concatenation
6614 Make_Expression_With_Actions (Sloc (Cnode),
6615 Actions => New_List (Make_Null_Statement (Sloc (Cnode))),
6616 Expression => Cnod));
6618 Expand_Concatenate (Cnod, Opnds);
6619 Analyze_And_Resolve (Cnode, Typ);
6625 Expand_Concatenate (Cnode, Opnds);
6628 exit Outer when Cnode = N;
6629 Cnode := Parent (Cnode);
6631 end Expand_N_Op_Concat;
6633 ------------------------
6634 -- Expand_N_Op_Divide --
6635 ------------------------
6637 procedure Expand_N_Op_Divide (N : Node_Id) is
6638 Loc : constant Source_Ptr := Sloc (N);
6639 Lopnd : constant Node_Id := Left_Opnd (N);
6640 Ropnd : constant Node_Id := Right_Opnd (N);
6641 Ltyp : constant Entity_Id := Etype (Lopnd);
6642 Rtyp : constant Entity_Id := Etype (Ropnd);
6643 Typ : Entity_Id := Etype (N);
6644 Rknow : constant Boolean := Is_Integer_Type (Typ)
6646 Compile_Time_Known_Value (Ropnd);
6650 Binary_Op_Validity_Checks (N);
6652 -- Check for MINIMIZED/ELIMINATED overflow mode
6654 if Minimized_Eliminated_Overflow_Check (N) then
6655 Apply_Arithmetic_Overflow_Check (N);
6659 -- Otherwise proceed with expansion of division
6662 Rval := Expr_Value (Ropnd);
6665 -- N / 1 = N for integer types
6667 if Rknow and then Rval = Uint_1 then
6672 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
6673 -- Is_Power_Of_2_For_Shift is set means that we know that our left
6674 -- operand is an unsigned integer, as required for this to work.
6676 if Nkind (Ropnd) = N_Op_Expon
6677 and then Is_Power_Of_2_For_Shift (Ropnd)
6679 -- We cannot do this transformation in configurable run time mode if we
6680 -- have 64-bit integers and long shifts are not available.
6682 and then (Esize (Ltyp) <= 32 or else Support_Long_Shifts_On_Target)
6685 Make_Op_Shift_Right (Loc,
6688 Convert_To (Standard_Natural, Right_Opnd (Ropnd))));
6689 Analyze_And_Resolve (N, Typ);
6693 -- Do required fixup of universal fixed operation
6695 if Typ = Universal_Fixed then
6696 Fixup_Universal_Fixed_Operation (N);
6700 -- Divisions with fixed-point results
6702 if Is_Fixed_Point_Type (Typ) then
6704 -- Deal with divide-by-zero check if back end cannot handle them
6705 -- and the flag is set indicating that we need such a check. Note
6706 -- that we don't need to bother here with the case of mixed-mode
6707 -- (Right operand an integer type), since these will be rewritten
6708 -- with conversions to a divide with a fixed-point right operand.
6710 if Do_Division_Check (N)
6711 and then not Backend_Divide_Checks_On_Target
6712 and then not Is_Integer_Type (Rtyp)
6714 Set_Do_Division_Check (N, False);
6716 Make_Raise_Constraint_Error (Loc,
6719 Left_Opnd => Duplicate_Subexpr_Move_Checks (Ropnd),
6720 Right_Opnd => Make_Real_Literal (Loc, Ureal_0)),
6721 Reason => CE_Divide_By_Zero));
6724 -- No special processing if Treat_Fixed_As_Integer is set, since
6725 -- from a semantic point of view such operations are simply integer
6726 -- operations and will be treated that way.
6728 if not Treat_Fixed_As_Integer (N) then
6729 if Is_Integer_Type (Rtyp) then
6730 Expand_Divide_Fixed_By_Integer_Giving_Fixed (N);
6732 Expand_Divide_Fixed_By_Fixed_Giving_Fixed (N);
6736 -- Other cases of division of fixed-point operands. Again we exclude the
6737 -- case where Treat_Fixed_As_Integer is set.
6739 elsif (Is_Fixed_Point_Type (Ltyp) or else Is_Fixed_Point_Type (Rtyp))
6740 and then not Treat_Fixed_As_Integer (N)
6742 if Is_Integer_Type (Typ) then
6743 Expand_Divide_Fixed_By_Fixed_Giving_Integer (N);
6745 pragma Assert (Is_Floating_Point_Type (Typ));
6746 Expand_Divide_Fixed_By_Fixed_Giving_Float (N);
6749 -- Mixed-mode operations can appear in a non-static universal context,
6750 -- in which case the integer argument must be converted explicitly.
6752 elsif Typ = Universal_Real and then Is_Integer_Type (Rtyp) then
6754 Convert_To (Universal_Real, Relocate_Node (Ropnd)));
6756 Analyze_And_Resolve (Ropnd, Universal_Real);
6758 elsif Typ = Universal_Real and then Is_Integer_Type (Ltyp) then
6760 Convert_To (Universal_Real, Relocate_Node (Lopnd)));
6762 Analyze_And_Resolve (Lopnd, Universal_Real);
6764 -- Non-fixed point cases, do integer zero divide and overflow checks
6766 elsif Is_Integer_Type (Typ) then
6767 Apply_Divide_Checks (N);
6770 -- Overflow checks for floating-point if -gnateF mode active
6772 Check_Float_Op_Overflow (N);
6773 end Expand_N_Op_Divide;
6775 --------------------
6776 -- Expand_N_Op_Eq --
6777 --------------------
6779 procedure Expand_N_Op_Eq (N : Node_Id) is
6780 Loc : constant Source_Ptr := Sloc (N);
6781 Typ : constant Entity_Id := Etype (N);
6782 Lhs : constant Node_Id := Left_Opnd (N);
6783 Rhs : constant Node_Id := Right_Opnd (N);
6784 Bodies : constant List_Id := New_List;
6785 A_Typ : constant Entity_Id := Etype (Lhs);
6787 Typl : Entity_Id := A_Typ;
6788 Op_Name : Entity_Id;
6791 procedure Build_Equality_Call (Eq : Entity_Id);
6792 -- If a constructed equality exists for the type or for its parent,
6793 -- build and analyze call, adding conversions if the operation is
6796 function Has_Unconstrained_UU_Component (Typ : Node_Id) return Boolean;
6797 -- Determines whether a type has a subcomponent of an unconstrained
6798 -- Unchecked_Union subtype. Typ is a record type.
6800 -------------------------
6801 -- Build_Equality_Call --
6802 -------------------------
6804 procedure Build_Equality_Call (Eq : Entity_Id) is
6805 Op_Type : constant Entity_Id := Etype (First_Formal (Eq));
6806 L_Exp : Node_Id := Relocate_Node (Lhs);
6807 R_Exp : Node_Id := Relocate_Node (Rhs);
6810 -- Adjust operands if necessary to comparison type
6812 if Base_Type (Op_Type) /= Base_Type (A_Typ)
6813 and then not Is_Class_Wide_Type (A_Typ)
6815 L_Exp := OK_Convert_To (Op_Type, L_Exp);
6816 R_Exp := OK_Convert_To (Op_Type, R_Exp);
6819 -- If we have an Unchecked_Union, we need to add the inferred
6820 -- discriminant values as actuals in the function call. At this
6821 -- point, the expansion has determined that both operands have
6822 -- inferable discriminants.
6824 if Is_Unchecked_Union (Op_Type) then
6826 Lhs_Type : constant Node_Id := Etype (L_Exp);
6827 Rhs_Type : constant Node_Id := Etype (R_Exp);
6829 Lhs_Discr_Vals : Elist_Id;
6830 -- List of inferred discriminant values for left operand.
6832 Rhs_Discr_Vals : Elist_Id;
6833 -- List of inferred discriminant values for right operand.
6838 Lhs_Discr_Vals := New_Elmt_List;
6839 Rhs_Discr_Vals := New_Elmt_List;
6841 -- Per-object constrained selected components require special
6842 -- attention. If the enclosing scope of the component is an
6843 -- Unchecked_Union, we cannot reference its discriminants
6844 -- directly. This is why we use the extra parameters of the
6845 -- equality function of the enclosing Unchecked_Union.
6847 -- type UU_Type (Discr : Integer := 0) is
6850 -- pragma Unchecked_Union (UU_Type);
6852 -- 1. Unchecked_Union enclosing record:
6854 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
6856 -- Comp : UU_Type (Discr);
6858 -- end Enclosing_UU_Type;
6859 -- pragma Unchecked_Union (Enclosing_UU_Type);
6861 -- Obj1 : Enclosing_UU_Type;
6862 -- Obj2 : Enclosing_UU_Type (1);
6864 -- [. . .] Obj1 = Obj2 [. . .]
6868 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
6870 -- A and B are the formal parameters of the equality function
6871 -- of Enclosing_UU_Type. The function always has two extra
6872 -- formals to capture the inferred discriminant values for
6873 -- each discriminant of the type.
6875 -- 2. Non-Unchecked_Union enclosing record:
6878 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
6881 -- Comp : UU_Type (Discr);
6883 -- end Enclosing_Non_UU_Type;
6885 -- Obj1 : Enclosing_Non_UU_Type;
6886 -- Obj2 : Enclosing_Non_UU_Type (1);
6888 -- ... Obj1 = Obj2 ...
6892 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
6893 -- obj1.discr, obj2.discr)) then
6895 -- In this case we can directly reference the discriminants of
6896 -- the enclosing record.
6898 -- Process left operand of equality
6900 if Nkind (Lhs) = N_Selected_Component
6902 Has_Per_Object_Constraint (Entity (Selector_Name (Lhs)))
6904 -- If enclosing record is an Unchecked_Union, use formals
6905 -- corresponding to each discriminant. The name of the
6906 -- formal is that of the discriminant, with added suffix,
6907 -- see Exp_Ch3.Build_Record_Equality for details.
6909 if Is_Unchecked_Union (Scope (Entity (Selector_Name (Lhs))))
6913 (Scope (Entity (Selector_Name (Lhs))));
6914 while Present (Discr) loop
6916 (Make_Identifier (Loc,
6917 Chars => New_External_Name (Chars (Discr), 'A')),
6918 To => Lhs_Discr_Vals);
6919 Next_Discriminant (Discr);
6922 -- If enclosing record is of a non-Unchecked_Union type, it
6923 -- is possible to reference its discriminants directly.
6926 Discr := First_Discriminant (Lhs_Type);
6927 while Present (Discr) loop
6929 (Make_Selected_Component (Loc,
6930 Prefix => Prefix (Lhs),
6933 (Get_Discriminant_Value (Discr,
6935 Stored_Constraint (Lhs_Type)))),
6936 To => Lhs_Discr_Vals);
6937 Next_Discriminant (Discr);
6941 -- Otherwise operand is on object with a constrained type.
6942 -- Infer the discriminant values from the constraint.
6946 Discr := First_Discriminant (Lhs_Type);
6947 while Present (Discr) loop
6950 (Get_Discriminant_Value (Discr,
6952 Stored_Constraint (Lhs_Type))),
6953 To => Lhs_Discr_Vals);
6954 Next_Discriminant (Discr);
6958 -- Similar processing for right operand of equality
6960 if Nkind (Rhs) = N_Selected_Component
6962 Has_Per_Object_Constraint (Entity (Selector_Name (Rhs)))
6964 if Is_Unchecked_Union
6965 (Scope (Entity (Selector_Name (Rhs))))
6969 (Scope (Entity (Selector_Name (Rhs))));
6970 while Present (Discr) loop
6972 (Make_Identifier (Loc,
6973 Chars => New_External_Name (Chars (Discr), 'B')),
6974 To => Rhs_Discr_Vals);
6975 Next_Discriminant (Discr);
6979 Discr := First_Discriminant (Rhs_Type);
6980 while Present (Discr) loop
6982 (Make_Selected_Component (Loc,
6983 Prefix => Prefix (Rhs),
6985 New_Copy (Get_Discriminant_Value
6988 Stored_Constraint (Rhs_Type)))),
6989 To => Rhs_Discr_Vals);
6990 Next_Discriminant (Discr);
6995 Discr := First_Discriminant (Rhs_Type);
6996 while Present (Discr) loop
6998 (New_Copy (Get_Discriminant_Value
7001 Stored_Constraint (Rhs_Type))),
7002 To => Rhs_Discr_Vals);
7003 Next_Discriminant (Discr);
7007 -- Now merge the list of discriminant values so that values
7008 -- of corresponding discriminants are adjacent.
7016 Params := New_List (L_Exp, R_Exp);
7017 L_Elmt := First_Elmt (Lhs_Discr_Vals);
7018 R_Elmt := First_Elmt (Rhs_Discr_Vals);
7019 while Present (L_Elmt) loop
7020 Append_To (Params, Node (L_Elmt));
7021 Append_To (Params, Node (R_Elmt));
7027 Make_Function_Call (Loc,
7028 Name => New_Occurrence_Of (Eq, Loc),
7029 Parameter_Associations => Params));
7033 -- Normal case, not an unchecked union
7037 Make_Function_Call (Loc,
7038 Name => New_Occurrence_Of (Eq, Loc),
7039 Parameter_Associations => New_List (L_Exp, R_Exp)));
7042 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
7043 end Build_Equality_Call;
7045 ------------------------------------
7046 -- Has_Unconstrained_UU_Component --
7047 ------------------------------------
7049 function Has_Unconstrained_UU_Component
7050 (Typ : Node_Id) return Boolean
7052 Tdef : constant Node_Id :=
7053 Type_Definition (Declaration_Node (Base_Type (Typ)));
7057 function Component_Is_Unconstrained_UU
7058 (Comp : Node_Id) return Boolean;
7059 -- Determines whether the subtype of the component is an
7060 -- unconstrained Unchecked_Union.
7062 function Variant_Is_Unconstrained_UU
7063 (Variant : Node_Id) return Boolean;
7064 -- Determines whether a component of the variant has an unconstrained
7065 -- Unchecked_Union subtype.
7067 -----------------------------------
7068 -- Component_Is_Unconstrained_UU --
7069 -----------------------------------
7071 function Component_Is_Unconstrained_UU
7072 (Comp : Node_Id) return Boolean
7075 if Nkind (Comp) /= N_Component_Declaration then
7080 Sindic : constant Node_Id :=
7081 Subtype_Indication (Component_Definition (Comp));
7084 -- Unconstrained nominal type. In the case of a constraint
7085 -- present, the node kind would have been N_Subtype_Indication.
7087 if Nkind (Sindic) = N_Identifier then
7088 return Is_Unchecked_Union (Base_Type (Etype (Sindic)));
7093 end Component_Is_Unconstrained_UU;
7095 ---------------------------------
7096 -- Variant_Is_Unconstrained_UU --
7097 ---------------------------------
7099 function Variant_Is_Unconstrained_UU
7100 (Variant : Node_Id) return Boolean
7102 Clist : constant Node_Id := Component_List (Variant);
7105 if Is_Empty_List (Component_Items (Clist)) then
7109 -- We only need to test one component
7112 Comp : Node_Id := First (Component_Items (Clist));
7115 while Present (Comp) loop
7116 if Component_Is_Unconstrained_UU (Comp) then
7124 -- None of the components withing the variant were of
7125 -- unconstrained Unchecked_Union type.
7128 end Variant_Is_Unconstrained_UU;
7130 -- Start of processing for Has_Unconstrained_UU_Component
7133 if Null_Present (Tdef) then
7137 Clist := Component_List (Tdef);
7138 Vpart := Variant_Part (Clist);
7140 -- Inspect available components
7142 if Present (Component_Items (Clist)) then
7144 Comp : Node_Id := First (Component_Items (Clist));
7147 while Present (Comp) loop
7149 -- One component is sufficient
7151 if Component_Is_Unconstrained_UU (Comp) then
7160 -- Inspect available components withing variants
7162 if Present (Vpart) then
7164 Variant : Node_Id := First (Variants (Vpart));
7167 while Present (Variant) loop
7169 -- One component within a variant is sufficient
7171 if Variant_Is_Unconstrained_UU (Variant) then
7180 -- Neither the available components, nor the components inside the
7181 -- variant parts were of an unconstrained Unchecked_Union subtype.
7184 end Has_Unconstrained_UU_Component;
7186 -- Start of processing for Expand_N_Op_Eq
7189 Binary_Op_Validity_Checks (N);
7191 -- Deal with private types
7193 if Ekind (Typl) = E_Private_Type then
7194 Typl := Underlying_Type (Typl);
7195 elsif Ekind (Typl) = E_Private_Subtype then
7196 Typl := Underlying_Type (Base_Type (Typl));
7201 -- It may happen in error situations that the underlying type is not
7202 -- set. The error will be detected later, here we just defend the
7209 -- Now get the implementation base type (note that plain Base_Type here
7210 -- might lead us back to the private type, which is not what we want!)
7212 Typl := Implementation_Base_Type (Typl);
7214 -- Equality between variant records results in a call to a routine
7215 -- that has conditional tests of the discriminant value(s), and hence
7216 -- violates the No_Implicit_Conditionals restriction.
7218 if Has_Variant_Part (Typl) then
7223 Check_Restriction (Msg, No_Implicit_Conditionals, N);
7227 ("\comparison of variant records tests discriminants", N);
7233 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7234 -- means we no longer have a comparison operation, we are all done.
7236 Expand_Compare_Minimize_Eliminate_Overflow (N);
7238 if Nkind (N) /= N_Op_Eq then
7242 -- Boolean types (requiring handling of non-standard case)
7244 if Is_Boolean_Type (Typl) then
7245 Adjust_Condition (Left_Opnd (N));
7246 Adjust_Condition (Right_Opnd (N));
7247 Set_Etype (N, Standard_Boolean);
7248 Adjust_Result_Type (N, Typ);
7252 elsif Is_Array_Type (Typl) then
7254 -- If we are doing full validity checking, and it is possible for the
7255 -- array elements to be invalid then expand out array comparisons to
7256 -- make sure that we check the array elements.
7258 if Validity_Check_Operands
7259 and then not Is_Known_Valid (Component_Type (Typl))
7262 Save_Force_Validity_Checks : constant Boolean :=
7263 Force_Validity_Checks;
7265 Force_Validity_Checks := True;
7267 Expand_Array_Equality
7269 Relocate_Node (Lhs),
7270 Relocate_Node (Rhs),
7273 Insert_Actions (N, Bodies);
7274 Analyze_And_Resolve (N, Standard_Boolean);
7275 Force_Validity_Checks := Save_Force_Validity_Checks;
7278 -- Packed case where both operands are known aligned
7280 elsif Is_Bit_Packed_Array (Typl)
7281 and then not Is_Possibly_Unaligned_Object (Lhs)
7282 and then not Is_Possibly_Unaligned_Object (Rhs)
7284 Expand_Packed_Eq (N);
7286 -- Where the component type is elementary we can use a block bit
7287 -- comparison (if supported on the target) exception in the case
7288 -- of floating-point (negative zero issues require element by
7289 -- element comparison), and atomic types (where we must be sure
7290 -- to load elements independently) and possibly unaligned arrays.
7292 elsif Is_Elementary_Type (Component_Type (Typl))
7293 and then not Is_Floating_Point_Type (Component_Type (Typl))
7294 and then not Is_Atomic (Component_Type (Typl))
7295 and then not Is_Possibly_Unaligned_Object (Lhs)
7296 and then not Is_Possibly_Unaligned_Object (Rhs)
7297 and then Support_Composite_Compare_On_Target
7301 -- For composite and floating-point cases, expand equality loop to
7302 -- make sure of using proper comparisons for tagged types, and
7303 -- correctly handling the floating-point case.
7307 Expand_Array_Equality
7309 Relocate_Node (Lhs),
7310 Relocate_Node (Rhs),
7313 Insert_Actions (N, Bodies, Suppress => All_Checks);
7314 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
7319 elsif Is_Record_Type (Typl) then
7321 -- For tagged types, use the primitive "="
7323 if Is_Tagged_Type (Typl) then
7325 -- No need to do anything else compiling under restriction
7326 -- No_Dispatching_Calls. During the semantic analysis we
7327 -- already notified such violation.
7329 if Restriction_Active (No_Dispatching_Calls) then
7333 -- If this is derived from an untagged private type completed with
7334 -- a tagged type, it does not have a full view, so we use the
7335 -- primitive operations of the private type. This check should no
7336 -- longer be necessary when these types get their full views???
7338 if Is_Private_Type (A_Typ)
7339 and then not Is_Tagged_Type (A_Typ)
7340 and then Is_Derived_Type (A_Typ)
7341 and then No (Full_View (A_Typ))
7343 -- Search for equality operation, checking that the operands
7344 -- have the same type. Note that we must find a matching entry,
7345 -- or something is very wrong.
7347 Prim := First_Elmt (Collect_Primitive_Operations (A_Typ));
7349 while Present (Prim) loop
7350 exit when Chars (Node (Prim)) = Name_Op_Eq
7351 and then Etype (First_Formal (Node (Prim))) =
7352 Etype (Next_Formal (First_Formal (Node (Prim))))
7354 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
7359 pragma Assert (Present (Prim));
7360 Op_Name := Node (Prim);
7362 -- Find the type's predefined equality or an overriding
7363 -- user-defined equality. The reason for not simply calling
7364 -- Find_Prim_Op here is that there may be a user-defined
7365 -- overloaded equality op that precedes the equality that we
7366 -- want, so we have to explicitly search (e.g., there could be
7367 -- an equality with two different parameter types).
7370 if Is_Class_Wide_Type (Typl) then
7371 Typl := Find_Specific_Type (Typl);
7374 Prim := First_Elmt (Primitive_Operations (Typl));
7375 while Present (Prim) loop
7376 exit when Chars (Node (Prim)) = Name_Op_Eq
7377 and then Etype (First_Formal (Node (Prim))) =
7378 Etype (Next_Formal (First_Formal (Node (Prim))))
7380 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
7385 pragma Assert (Present (Prim));
7386 Op_Name := Node (Prim);
7389 Build_Equality_Call (Op_Name);
7391 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
7392 -- predefined equality operator for a type which has a subcomponent
7393 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
7395 elsif Has_Unconstrained_UU_Component (Typl) then
7397 Make_Raise_Program_Error (Loc,
7398 Reason => PE_Unchecked_Union_Restriction));
7400 -- Prevent Gigi from generating incorrect code by rewriting the
7401 -- equality as a standard False. (is this documented somewhere???)
7404 New_Occurrence_Of (Standard_False, Loc));
7406 elsif Is_Unchecked_Union (Typl) then
7408 -- If we can infer the discriminants of the operands, we make a
7409 -- call to the TSS equality function.
7411 if Has_Inferable_Discriminants (Lhs)
7413 Has_Inferable_Discriminants (Rhs)
7416 (TSS (Root_Type (Typl), TSS_Composite_Equality));
7419 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
7420 -- the predefined equality operator for an Unchecked_Union type
7421 -- if either of the operands lack inferable discriminants.
7424 Make_Raise_Program_Error (Loc,
7425 Reason => PE_Unchecked_Union_Restriction));
7427 -- Emit a warning on source equalities only, otherwise the
7428 -- message may appear out of place due to internal use. The
7429 -- warning is unconditional because it is required by the
7432 if Comes_From_Source (N) then
7434 ("Unchecked_Union discriminants cannot be determined??",
7437 ("\Program_Error will be raised for equality operation??",
7441 -- Prevent Gigi from generating incorrect code by rewriting
7442 -- the equality as a standard False (documented where???).
7445 New_Occurrence_Of (Standard_False, Loc));
7448 -- If a type support function is present (for complex cases), use it
7450 elsif Present (TSS (Root_Type (Typl), TSS_Composite_Equality)) then
7452 (TSS (Root_Type (Typl), TSS_Composite_Equality));
7454 -- When comparing two Bounded_Strings, use the primitive equality of
7455 -- the root Super_String type.
7457 elsif Is_Bounded_String (Typl) then
7459 First_Elmt (Collect_Primitive_Operations (Root_Type (Typl)));
7461 while Present (Prim) loop
7462 exit when Chars (Node (Prim)) = Name_Op_Eq
7463 and then Etype (First_Formal (Node (Prim))) =
7464 Etype (Next_Formal (First_Formal (Node (Prim))))
7465 and then Base_Type (Etype (Node (Prim))) = Standard_Boolean;
7470 -- A Super_String type should always have a primitive equality
7472 pragma Assert (Present (Prim));
7473 Build_Equality_Call (Node (Prim));
7475 -- Otherwise expand the component by component equality. Note that
7476 -- we never use block-bit comparisons for records, because of the
7477 -- problems with gaps. The backend will often be able to recombine
7478 -- the separate comparisons that we generate here.
7481 Remove_Side_Effects (Lhs);
7482 Remove_Side_Effects (Rhs);
7484 Expand_Record_Equality (N, Typl, Lhs, Rhs, Bodies));
7486 Insert_Actions (N, Bodies, Suppress => All_Checks);
7487 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
7491 -- Test if result is known at compile time
7493 Rewrite_Comparison (N);
7495 Optimize_Length_Comparison (N);
7498 -----------------------
7499 -- Expand_N_Op_Expon --
7500 -----------------------
7502 procedure Expand_N_Op_Expon (N : Node_Id) is
7503 Loc : constant Source_Ptr := Sloc (N);
7504 Typ : constant Entity_Id := Etype (N);
7505 Rtyp : constant Entity_Id := Root_Type (Typ);
7506 Base : constant Node_Id := Relocate_Node (Left_Opnd (N));
7507 Bastyp : constant Node_Id := Etype (Base);
7508 Exp : constant Node_Id := Relocate_Node (Right_Opnd (N));
7509 Exptyp : constant Entity_Id := Etype (Exp);
7510 Ovflo : constant Boolean := Do_Overflow_Check (N);
7519 Binary_Op_Validity_Checks (N);
7521 -- CodePeer wants to see the unexpanded N_Op_Expon node
7523 if CodePeer_Mode then
7527 -- If either operand is of a private type, then we have the use of an
7528 -- intrinsic operator, and we get rid of the privateness, by using root
7529 -- types of underlying types for the actual operation. Otherwise the
7530 -- private types will cause trouble if we expand multiplications or
7531 -- shifts etc. We also do this transformation if the result type is
7532 -- different from the base type.
7534 if Is_Private_Type (Etype (Base))
7535 or else Is_Private_Type (Typ)
7536 or else Is_Private_Type (Exptyp)
7537 or else Rtyp /= Root_Type (Bastyp)
7540 Bt : constant Entity_Id := Root_Type (Underlying_Type (Bastyp));
7541 Et : constant Entity_Id := Root_Type (Underlying_Type (Exptyp));
7544 Unchecked_Convert_To (Typ,
7546 Left_Opnd => Unchecked_Convert_To (Bt, Base),
7547 Right_Opnd => Unchecked_Convert_To (Et, Exp))));
7548 Analyze_And_Resolve (N, Typ);
7553 -- Check for MINIMIZED/ELIMINATED overflow mode
7555 if Minimized_Eliminated_Overflow_Check (N) then
7556 Apply_Arithmetic_Overflow_Check (N);
7560 -- Test for case of known right argument where we can replace the
7561 -- exponentiation by an equivalent expression using multiplication.
7563 -- Note: use CRT_Safe version of Compile_Time_Known_Value because in
7564 -- configurable run-time mode, we may not have the exponentiation
7565 -- routine available, and we don't want the legality of the program
7566 -- to depend on how clever the compiler is in knowing values.
7568 if CRT_Safe_Compile_Time_Known_Value (Exp) then
7569 Expv := Expr_Value (Exp);
7571 -- We only fold small non-negative exponents. You might think we
7572 -- could fold small negative exponents for the real case, but we
7573 -- can't because we are required to raise Constraint_Error for
7574 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
7575 -- See ACVC test C4A012B.
7577 if Expv >= 0 and then Expv <= 4 then
7579 -- X ** 0 = 1 (or 1.0)
7583 -- Call Remove_Side_Effects to ensure that any side effects
7584 -- in the ignored left operand (in particular function calls
7585 -- to user defined functions) are properly executed.
7587 Remove_Side_Effects (Base);
7589 if Ekind (Typ) in Integer_Kind then
7590 Xnode := Make_Integer_Literal (Loc, Intval => 1);
7592 Xnode := Make_Real_Literal (Loc, Ureal_1);
7604 Make_Op_Multiply (Loc,
7605 Left_Opnd => Duplicate_Subexpr (Base),
7606 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
7608 -- X ** 3 = X * X * X
7612 Make_Op_Multiply (Loc,
7614 Make_Op_Multiply (Loc,
7615 Left_Opnd => Duplicate_Subexpr (Base),
7616 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)),
7617 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
7622 -- En : constant base'type := base * base;
7627 pragma Assert (Expv = 4);
7628 Temp := Make_Temporary (Loc, 'E', Base);
7631 Make_Expression_With_Actions (Loc,
7632 Actions => New_List (
7633 Make_Object_Declaration (Loc,
7634 Defining_Identifier => Temp,
7635 Constant_Present => True,
7636 Object_Definition => New_Occurrence_Of (Typ, Loc),
7638 Make_Op_Multiply (Loc,
7640 Duplicate_Subexpr (Base),
7642 Duplicate_Subexpr_No_Checks (Base)))),
7645 Make_Op_Multiply (Loc,
7646 Left_Opnd => New_Occurrence_Of (Temp, Loc),
7647 Right_Opnd => New_Occurrence_Of (Temp, Loc)));
7651 Analyze_And_Resolve (N, Typ);
7656 -- Case of (2 ** expression) appearing as an argument of an integer
7657 -- multiplication, or as the right argument of a division of a non-
7658 -- negative integer. In such cases we leave the node untouched, setting
7659 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
7660 -- of the higher level node converts it into a shift.
7662 -- Another case is 2 ** N in any other context. We simply convert
7663 -- this to 1 * 2 ** N, and then the above transformation applies.
7665 -- Note: this transformation is not applicable for a modular type with
7666 -- a non-binary modulus in the multiplication case, since we get a wrong
7667 -- result if the shift causes an overflow before the modular reduction.
7669 -- Note: we used to check that Exptyp was an unsigned type. But that is
7670 -- an unnecessary check, since if Exp is negative, we have a run-time
7671 -- error that is either caught (so we get the right result) or we have
7672 -- suppressed the check, in which case the code is erroneous anyway.
7674 if Nkind (Base) = N_Integer_Literal
7675 and then CRT_Safe_Compile_Time_Known_Value (Base)
7676 and then Expr_Value (Base) = Uint_2
7677 and then Is_Integer_Type (Root_Type (Exptyp))
7678 and then Esize (Root_Type (Exptyp)) <= Esize (Standard_Integer)
7681 -- First the multiply and divide cases
7683 if Nkind_In (Parent (N), N_Op_Divide, N_Op_Multiply) then
7685 P : constant Node_Id := Parent (N);
7686 L : constant Node_Id := Left_Opnd (P);
7687 R : constant Node_Id := Right_Opnd (P);
7690 if (Nkind (P) = N_Op_Multiply
7691 and then not Non_Binary_Modulus (Typ)
7693 ((Is_Integer_Type (Etype (L)) and then R = N)
7695 (Is_Integer_Type (Etype (R)) and then L = N))
7696 and then not Do_Overflow_Check (P))
7698 (Nkind (P) = N_Op_Divide
7699 and then Is_Integer_Type (Etype (L))
7700 and then Is_Unsigned_Type (Etype (L))
7702 and then not Do_Overflow_Check (P))
7704 Set_Is_Power_Of_2_For_Shift (N);
7709 -- Now the other cases
7711 elsif not Non_Binary_Modulus (Typ) then
7713 Make_Op_Multiply (Loc,
7714 Left_Opnd => Make_Integer_Literal (Loc, 1),
7715 Right_Opnd => Relocate_Node (N)));
7716 Analyze_And_Resolve (N, Typ);
7721 -- Fall through if exponentiation must be done using a runtime routine
7723 -- First deal with modular case
7725 if Is_Modular_Integer_Type (Rtyp) then
7727 -- Non-binary case, we call the special exponentiation routine for
7728 -- the non-binary case, converting the argument to Long_Long_Integer
7729 -- and passing the modulus value. Then the result is converted back
7730 -- to the base type.
7732 if Non_Binary_Modulus (Rtyp) then
7735 Make_Function_Call (Loc,
7737 New_Occurrence_Of (RTE (RE_Exp_Modular), Loc),
7738 Parameter_Associations => New_List (
7739 Convert_To (RTE (RE_Unsigned), Base),
7740 Make_Integer_Literal (Loc, Modulus (Rtyp)),
7743 -- Binary case, in this case, we call one of two routines, either the
7744 -- unsigned integer case, or the unsigned long long integer case,
7745 -- with a final "and" operation to do the required mod.
7748 if UI_To_Int (Esize (Rtyp)) <= Standard_Integer_Size then
7749 Ent := RTE (RE_Exp_Unsigned);
7751 Ent := RTE (RE_Exp_Long_Long_Unsigned);
7758 Make_Function_Call (Loc,
7759 Name => New_Occurrence_Of (Ent, Loc),
7760 Parameter_Associations => New_List (
7761 Convert_To (Etype (First_Formal (Ent)), Base),
7764 Make_Integer_Literal (Loc, Modulus (Rtyp) - 1))));
7768 -- Common exit point for modular type case
7770 Analyze_And_Resolve (N, Typ);
7773 -- Signed integer cases, done using either Integer or Long_Long_Integer.
7774 -- It is not worth having routines for Short_[Short_]Integer, since for
7775 -- most machines it would not help, and it would generate more code that
7776 -- might need certification when a certified run time is required.
7778 -- In the integer cases, we have two routines, one for when overflow
7779 -- checks are required, and one when they are not required, since there
7780 -- is a real gain in omitting checks on many machines.
7782 elsif Rtyp = Base_Type (Standard_Long_Long_Integer)
7783 or else (Rtyp = Base_Type (Standard_Long_Integer)
7785 Esize (Standard_Long_Integer) > Esize (Standard_Integer))
7786 or else Rtyp = Universal_Integer
7788 Etyp := Standard_Long_Long_Integer;
7790 -- Overflow checking is the only choice on the AAMP target, where
7791 -- arithmetic instructions check overflow automatically, so only
7792 -- one version of the exponentiation unit is needed.
7794 if Ovflo or AAMP_On_Target then
7795 Rent := RE_Exp_Long_Long_Integer;
7797 Rent := RE_Exn_Long_Long_Integer;
7800 elsif Is_Signed_Integer_Type (Rtyp) then
7801 Etyp := Standard_Integer;
7803 -- Overflow checking is the only choice on the AAMP target, where
7804 -- arithmetic instructions check overflow automatically, so only
7805 -- one version of the exponentiation unit is needed.
7807 if Ovflo or AAMP_On_Target then
7808 Rent := RE_Exp_Integer;
7810 Rent := RE_Exn_Integer;
7813 -- Floating-point cases, always done using Long_Long_Float. We do not
7814 -- need separate routines for the overflow case here, since in the case
7815 -- of floating-point, we generate infinities anyway as a rule (either
7816 -- that or we automatically trap overflow), and if there is an infinity
7817 -- generated and a range check is required, the check will fail anyway.
7820 pragma Assert (Is_Floating_Point_Type (Rtyp));
7821 Etyp := Standard_Long_Long_Float;
7822 Rent := RE_Exn_Long_Long_Float;
7825 -- Common processing for integer cases and floating-point cases.
7826 -- If we are in the right type, we can call runtime routine directly
7829 and then Rtyp /= Universal_Integer
7830 and then Rtyp /= Universal_Real
7833 Make_Function_Call (Loc,
7834 Name => New_Occurrence_Of (RTE (Rent), Loc),
7835 Parameter_Associations => New_List (Base, Exp)));
7837 -- Otherwise we have to introduce conversions (conversions are also
7838 -- required in the universal cases, since the runtime routine is
7839 -- typed using one of the standard types).
7844 Make_Function_Call (Loc,
7845 Name => New_Occurrence_Of (RTE (Rent), Loc),
7846 Parameter_Associations => New_List (
7847 Convert_To (Etyp, Base),
7851 Analyze_And_Resolve (N, Typ);
7855 when RE_Not_Available =>
7857 end Expand_N_Op_Expon;
7859 --------------------
7860 -- Expand_N_Op_Ge --
7861 --------------------
7863 procedure Expand_N_Op_Ge (N : Node_Id) is
7864 Typ : constant Entity_Id := Etype (N);
7865 Op1 : constant Node_Id := Left_Opnd (N);
7866 Op2 : constant Node_Id := Right_Opnd (N);
7867 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
7870 Binary_Op_Validity_Checks (N);
7872 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7873 -- means we no longer have a comparison operation, we are all done.
7875 Expand_Compare_Minimize_Eliminate_Overflow (N);
7877 if Nkind (N) /= N_Op_Ge then
7883 if Is_Array_Type (Typ1) then
7884 Expand_Array_Comparison (N);
7888 -- Deal with boolean operands
7890 if Is_Boolean_Type (Typ1) then
7891 Adjust_Condition (Op1);
7892 Adjust_Condition (Op2);
7893 Set_Etype (N, Standard_Boolean);
7894 Adjust_Result_Type (N, Typ);
7897 Rewrite_Comparison (N);
7899 Optimize_Length_Comparison (N);
7902 --------------------
7903 -- Expand_N_Op_Gt --
7904 --------------------
7906 procedure Expand_N_Op_Gt (N : Node_Id) is
7907 Typ : constant Entity_Id := Etype (N);
7908 Op1 : constant Node_Id := Left_Opnd (N);
7909 Op2 : constant Node_Id := Right_Opnd (N);
7910 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
7913 Binary_Op_Validity_Checks (N);
7915 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7916 -- means we no longer have a comparison operation, we are all done.
7918 Expand_Compare_Minimize_Eliminate_Overflow (N);
7920 if Nkind (N) /= N_Op_Gt then
7924 -- Deal with array type operands
7926 if Is_Array_Type (Typ1) then
7927 Expand_Array_Comparison (N);
7931 -- Deal with boolean type operands
7933 if Is_Boolean_Type (Typ1) then
7934 Adjust_Condition (Op1);
7935 Adjust_Condition (Op2);
7936 Set_Etype (N, Standard_Boolean);
7937 Adjust_Result_Type (N, Typ);
7940 Rewrite_Comparison (N);
7942 Optimize_Length_Comparison (N);
7945 --------------------
7946 -- Expand_N_Op_Le --
7947 --------------------
7949 procedure Expand_N_Op_Le (N : Node_Id) is
7950 Typ : constant Entity_Id := Etype (N);
7951 Op1 : constant Node_Id := Left_Opnd (N);
7952 Op2 : constant Node_Id := Right_Opnd (N);
7953 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
7956 Binary_Op_Validity_Checks (N);
7958 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
7959 -- means we no longer have a comparison operation, we are all done.
7961 Expand_Compare_Minimize_Eliminate_Overflow (N);
7963 if Nkind (N) /= N_Op_Le then
7967 -- Deal with array type operands
7969 if Is_Array_Type (Typ1) then
7970 Expand_Array_Comparison (N);
7974 -- Deal with Boolean type operands
7976 if Is_Boolean_Type (Typ1) then
7977 Adjust_Condition (Op1);
7978 Adjust_Condition (Op2);
7979 Set_Etype (N, Standard_Boolean);
7980 Adjust_Result_Type (N, Typ);
7983 Rewrite_Comparison (N);
7985 Optimize_Length_Comparison (N);
7988 --------------------
7989 -- Expand_N_Op_Lt --
7990 --------------------
7992 procedure Expand_N_Op_Lt (N : Node_Id) is
7993 Typ : constant Entity_Id := Etype (N);
7994 Op1 : constant Node_Id := Left_Opnd (N);
7995 Op2 : constant Node_Id := Right_Opnd (N);
7996 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
7999 Binary_Op_Validity_Checks (N);
8001 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if that
8002 -- means we no longer have a comparison operation, we are all done.
8004 Expand_Compare_Minimize_Eliminate_Overflow (N);
8006 if Nkind (N) /= N_Op_Lt then
8010 -- Deal with array type operands
8012 if Is_Array_Type (Typ1) then
8013 Expand_Array_Comparison (N);
8017 -- Deal with Boolean type operands
8019 if Is_Boolean_Type (Typ1) then
8020 Adjust_Condition (Op1);
8021 Adjust_Condition (Op2);
8022 Set_Etype (N, Standard_Boolean);
8023 Adjust_Result_Type (N, Typ);
8026 Rewrite_Comparison (N);
8028 Optimize_Length_Comparison (N);
8031 -----------------------
8032 -- Expand_N_Op_Minus --
8033 -----------------------
8035 procedure Expand_N_Op_Minus (N : Node_Id) is
8036 Loc : constant Source_Ptr := Sloc (N);
8037 Typ : constant Entity_Id := Etype (N);
8040 Unary_Op_Validity_Checks (N);
8042 -- Check for MINIMIZED/ELIMINATED overflow mode
8044 if Minimized_Eliminated_Overflow_Check (N) then
8045 Apply_Arithmetic_Overflow_Check (N);
8049 if not Backend_Overflow_Checks_On_Target
8050 and then Is_Signed_Integer_Type (Etype (N))
8051 and then Do_Overflow_Check (N)
8053 -- Software overflow checking expands -expr into (0 - expr)
8056 Make_Op_Subtract (Loc,
8057 Left_Opnd => Make_Integer_Literal (Loc, 0),
8058 Right_Opnd => Right_Opnd (N)));
8060 Analyze_And_Resolve (N, Typ);
8062 end Expand_N_Op_Minus;
8064 ---------------------
8065 -- Expand_N_Op_Mod --
8066 ---------------------
8068 procedure Expand_N_Op_Mod (N : Node_Id) is
8069 Loc : constant Source_Ptr := Sloc (N);
8070 Typ : constant Entity_Id := Etype (N);
8071 DDC : constant Boolean := Do_Division_Check (N);
8084 pragma Warnings (Off, Lhi);
8087 Binary_Op_Validity_Checks (N);
8089 -- Check for MINIMIZED/ELIMINATED overflow mode
8091 if Minimized_Eliminated_Overflow_Check (N) then
8092 Apply_Arithmetic_Overflow_Check (N);
8096 if Is_Integer_Type (Etype (N)) then
8097 Apply_Divide_Checks (N);
8099 -- All done if we don't have a MOD any more, which can happen as a
8100 -- result of overflow expansion in MINIMIZED or ELIMINATED modes.
8102 if Nkind (N) /= N_Op_Mod then
8107 -- Proceed with expansion of mod operator
8109 Left := Left_Opnd (N);
8110 Right := Right_Opnd (N);
8112 Determine_Range (Right, ROK, Rlo, Rhi, Assume_Valid => True);
8113 Determine_Range (Left, LOK, Llo, Lhi, Assume_Valid => True);
8115 -- Convert mod to rem if operands are both known to be non-negative, or
8116 -- both known to be non-positive (these are the cases in which rem and
8117 -- mod are the same, see (RM 4.5.5(28-30)). We do this since it is quite
8118 -- likely that this will improve the quality of code, (the operation now
8119 -- corresponds to the hardware remainder), and it does not seem likely
8120 -- that it could be harmful. It also avoids some cases of the elaborate
8121 -- expansion in Modify_Tree_For_C mode below (since Ada rem = C %).
8124 and then ((Llo >= 0 and then Rlo >= 0)
8126 (Lhi <= 0 and then Rhi <= 0))
8129 Make_Op_Rem (Sloc (N),
8130 Left_Opnd => Left_Opnd (N),
8131 Right_Opnd => Right_Opnd (N)));
8133 -- Instead of reanalyzing the node we do the analysis manually. This
8134 -- avoids anomalies when the replacement is done in an instance and
8135 -- is epsilon more efficient.
8137 Set_Entity (N, Standard_Entity (S_Op_Rem));
8139 Set_Do_Division_Check (N, DDC);
8140 Expand_N_Op_Rem (N);
8144 -- Otherwise, normal mod processing
8147 -- Apply optimization x mod 1 = 0. We don't really need that with
8148 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
8149 -- certainly harmless.
8151 if Is_Integer_Type (Etype (N))
8152 and then Compile_Time_Known_Value (Right)
8153 and then Expr_Value (Right) = Uint_1
8155 -- Call Remove_Side_Effects to ensure that any side effects in
8156 -- the ignored left operand (in particular function calls to
8157 -- user defined functions) are properly executed.
8159 Remove_Side_Effects (Left);
8161 Rewrite (N, Make_Integer_Literal (Loc, 0));
8162 Analyze_And_Resolve (N, Typ);
8166 -- If we still have a mod operator and we are in Modify_Tree_For_C
8167 -- mode, and we have a signed integer type, then here is where we do
8168 -- the rewrite in terms of Rem. Note this rewrite bypasses the need
8169 -- for the special handling of the annoying case of largest negative
8170 -- number mod minus one.
8172 if Nkind (N) = N_Op_Mod
8173 and then Is_Signed_Integer_Type (Typ)
8174 and then Modify_Tree_For_C
8176 -- In the general case, we expand A mod B as
8178 -- Tnn : constant typ := A rem B;
8180 -- (if (A >= 0) = (B >= 0) then Tnn
8181 -- elsif Tnn = 0 then 0
8184 -- The comparison can be written simply as A >= 0 if we know that
8185 -- B >= 0 which is a very common case.
8187 -- An important optimization is when B is known at compile time
8188 -- to be 2**K for some constant. In this case we can simply AND
8189 -- the left operand with the bit string 2**K-1 (i.e. K 1-bits)
8190 -- and that works for both the positive and negative cases.
8193 P2 : constant Nat := Power_Of_Two (Right);
8198 Unchecked_Convert_To (Typ,
8201 Unchecked_Convert_To
8202 (Corresponding_Unsigned_Type (Typ), Left),
8204 Make_Integer_Literal (Loc, 2 ** P2 - 1))));
8205 Analyze_And_Resolve (N, Typ);
8210 -- Here for the full rewrite
8213 Tnn : constant Entity_Id := Make_Temporary (Sloc (N), 'T', N);
8219 Left_Opnd => Duplicate_Subexpr_No_Checks (Left),
8220 Right_Opnd => Make_Integer_Literal (Loc, 0));
8222 if not LOK or else Rlo < 0 then
8228 Left_Opnd => Duplicate_Subexpr_No_Checks (Right),
8229 Right_Opnd => Make_Integer_Literal (Loc, 0)));
8233 Make_Object_Declaration (Loc,
8234 Defining_Identifier => Tnn,
8235 Constant_Present => True,
8236 Object_Definition => New_Occurrence_Of (Typ, Loc),
8240 Right_Opnd => Right)));
8243 Make_If_Expression (Loc,
8244 Expressions => New_List (
8246 New_Occurrence_Of (Tnn, Loc),
8247 Make_If_Expression (Loc,
8249 Expressions => New_List (
8251 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
8252 Right_Opnd => Make_Integer_Literal (Loc, 0)),
8253 Make_Integer_Literal (Loc, 0),
8255 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
8257 Duplicate_Subexpr_No_Checks (Right)))))));
8259 Analyze_And_Resolve (N, Typ);
8264 -- Deal with annoying case of largest negative number mod minus one.
8265 -- Gigi may not handle this case correctly, because on some targets,
8266 -- the mod value is computed using a divide instruction which gives
8267 -- an overflow trap for this case.
8269 -- It would be a bit more efficient to figure out which targets
8270 -- this is really needed for, but in practice it is reasonable
8271 -- to do the following special check in all cases, since it means
8272 -- we get a clearer message, and also the overhead is minimal given
8273 -- that division is expensive in any case.
8275 -- In fact the check is quite easy, if the right operand is -1, then
8276 -- the mod value is always 0, and we can just ignore the left operand
8277 -- completely in this case.
8279 -- This only applies if we still have a mod operator. Skip if we
8280 -- have already rewritten this (e.g. in the case of eliminated
8281 -- overflow checks which have driven us into bignum mode).
8283 if Nkind (N) = N_Op_Mod then
8285 -- The operand type may be private (e.g. in the expansion of an
8286 -- intrinsic operation) so we must use the underlying type to get
8287 -- the bounds, and convert the literals explicitly.
8291 (Type_Low_Bound (Base_Type (Underlying_Type (Etype (Left)))));
8293 if ((not ROK) or else (Rlo <= (-1) and then (-1) <= Rhi))
8294 and then ((not LOK) or else (Llo = LLB))
8297 Make_If_Expression (Loc,
8298 Expressions => New_List (
8300 Left_Opnd => Duplicate_Subexpr (Right),
8302 Unchecked_Convert_To (Typ,
8303 Make_Integer_Literal (Loc, -1))),
8304 Unchecked_Convert_To (Typ,
8305 Make_Integer_Literal (Loc, Uint_0)),
8306 Relocate_Node (N))));
8308 Set_Analyzed (Next (Next (First (Expressions (N)))));
8309 Analyze_And_Resolve (N, Typ);
8313 end Expand_N_Op_Mod;
8315 --------------------------
8316 -- Expand_N_Op_Multiply --
8317 --------------------------
8319 procedure Expand_N_Op_Multiply (N : Node_Id) is
8320 Loc : constant Source_Ptr := Sloc (N);
8321 Lop : constant Node_Id := Left_Opnd (N);
8322 Rop : constant Node_Id := Right_Opnd (N);
8324 Lp2 : constant Boolean :=
8325 Nkind (Lop) = N_Op_Expon and then Is_Power_Of_2_For_Shift (Lop);
8326 Rp2 : constant Boolean :=
8327 Nkind (Rop) = N_Op_Expon and then Is_Power_Of_2_For_Shift (Rop);
8329 Ltyp : constant Entity_Id := Etype (Lop);
8330 Rtyp : constant Entity_Id := Etype (Rop);
8331 Typ : Entity_Id := Etype (N);
8334 Binary_Op_Validity_Checks (N);
8336 -- Check for MINIMIZED/ELIMINATED overflow mode
8338 if Minimized_Eliminated_Overflow_Check (N) then
8339 Apply_Arithmetic_Overflow_Check (N);
8343 -- Special optimizations for integer types
8345 if Is_Integer_Type (Typ) then
8347 -- N * 0 = 0 for integer types
8349 if Compile_Time_Known_Value (Rop)
8350 and then Expr_Value (Rop) = Uint_0
8352 -- Call Remove_Side_Effects to ensure that any side effects in
8353 -- the ignored left operand (in particular function calls to
8354 -- user defined functions) are properly executed.
8356 Remove_Side_Effects (Lop);
8358 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
8359 Analyze_And_Resolve (N, Typ);
8363 -- Similar handling for 0 * N = 0
8365 if Compile_Time_Known_Value (Lop)
8366 and then Expr_Value (Lop) = Uint_0
8368 Remove_Side_Effects (Rop);
8369 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
8370 Analyze_And_Resolve (N, Typ);
8374 -- N * 1 = 1 * N = N for integer types
8376 -- This optimisation is not done if we are going to
8377 -- rewrite the product 1 * 2 ** N to a shift.
8379 if Compile_Time_Known_Value (Rop)
8380 and then Expr_Value (Rop) = Uint_1
8386 elsif Compile_Time_Known_Value (Lop)
8387 and then Expr_Value (Lop) = Uint_1
8395 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
8396 -- Is_Power_Of_2_For_Shift is set means that we know that our left
8397 -- operand is an integer, as required for this to work.
8402 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
8406 Left_Opnd => Make_Integer_Literal (Loc, 2),
8409 Left_Opnd => Right_Opnd (Lop),
8410 Right_Opnd => Right_Opnd (Rop))));
8411 Analyze_And_Resolve (N, Typ);
8415 -- If the result is modular, perform the reduction of the result
8418 if Is_Modular_Integer_Type (Typ)
8419 and then not Non_Binary_Modulus (Typ)
8424 Make_Op_Shift_Left (Loc,
8427 Convert_To (Standard_Natural, Right_Opnd (Rop))),
8429 Make_Integer_Literal (Loc, Modulus (Typ) - 1)));
8433 Make_Op_Shift_Left (Loc,
8436 Convert_To (Standard_Natural, Right_Opnd (Rop))));
8439 Analyze_And_Resolve (N, Typ);
8443 -- Same processing for the operands the other way round
8446 if Is_Modular_Integer_Type (Typ)
8447 and then not Non_Binary_Modulus (Typ)
8452 Make_Op_Shift_Left (Loc,
8455 Convert_To (Standard_Natural, Right_Opnd (Lop))),
8457 Make_Integer_Literal (Loc, Modulus (Typ) - 1)));
8461 Make_Op_Shift_Left (Loc,
8464 Convert_To (Standard_Natural, Right_Opnd (Lop))));
8467 Analyze_And_Resolve (N, Typ);
8471 -- Do required fixup of universal fixed operation
8473 if Typ = Universal_Fixed then
8474 Fixup_Universal_Fixed_Operation (N);
8478 -- Multiplications with fixed-point results
8480 if Is_Fixed_Point_Type (Typ) then
8482 -- No special processing if Treat_Fixed_As_Integer is set, since from
8483 -- a semantic point of view such operations are simply integer
8484 -- operations and will be treated that way.
8486 if not Treat_Fixed_As_Integer (N) then
8488 -- Case of fixed * integer => fixed
8490 if Is_Integer_Type (Rtyp) then
8491 Expand_Multiply_Fixed_By_Integer_Giving_Fixed (N);
8493 -- Case of integer * fixed => fixed
8495 elsif Is_Integer_Type (Ltyp) then
8496 Expand_Multiply_Integer_By_Fixed_Giving_Fixed (N);
8498 -- Case of fixed * fixed => fixed
8501 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed (N);
8505 -- Other cases of multiplication of fixed-point operands. Again we
8506 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
8508 elsif (Is_Fixed_Point_Type (Ltyp) or else Is_Fixed_Point_Type (Rtyp))
8509 and then not Treat_Fixed_As_Integer (N)
8511 if Is_Integer_Type (Typ) then
8512 Expand_Multiply_Fixed_By_Fixed_Giving_Integer (N);
8514 pragma Assert (Is_Floating_Point_Type (Typ));
8515 Expand_Multiply_Fixed_By_Fixed_Giving_Float (N);
8518 -- Mixed-mode operations can appear in a non-static universal context,
8519 -- in which case the integer argument must be converted explicitly.
8521 elsif Typ = Universal_Real and then Is_Integer_Type (Rtyp) then
8522 Rewrite (Rop, Convert_To (Universal_Real, Relocate_Node (Rop)));
8523 Analyze_And_Resolve (Rop, Universal_Real);
8525 elsif Typ = Universal_Real and then Is_Integer_Type (Ltyp) then
8526 Rewrite (Lop, Convert_To (Universal_Real, Relocate_Node (Lop)));
8527 Analyze_And_Resolve (Lop, Universal_Real);
8529 -- Non-fixed point cases, check software overflow checking required
8531 elsif Is_Signed_Integer_Type (Etype (N)) then
8532 Apply_Arithmetic_Overflow_Check (N);
8535 -- Overflow checks for floating-point if -gnateF mode active
8537 Check_Float_Op_Overflow (N);
8538 end Expand_N_Op_Multiply;
8540 --------------------
8541 -- Expand_N_Op_Ne --
8542 --------------------
8544 procedure Expand_N_Op_Ne (N : Node_Id) is
8545 Typ : constant Entity_Id := Etype (Left_Opnd (N));
8548 -- Case of elementary type with standard operator
8550 if Is_Elementary_Type (Typ)
8551 and then Sloc (Entity (N)) = Standard_Location
8553 Binary_Op_Validity_Checks (N);
8555 -- Deal with overflow checks in MINIMIZED/ELIMINATED mode and if
8556 -- means we no longer have a /= operation, we are all done.
8558 Expand_Compare_Minimize_Eliminate_Overflow (N);
8560 if Nkind (N) /= N_Op_Ne then
8564 -- Boolean types (requiring handling of non-standard case)
8566 if Is_Boolean_Type (Typ) then
8567 Adjust_Condition (Left_Opnd (N));
8568 Adjust_Condition (Right_Opnd (N));
8569 Set_Etype (N, Standard_Boolean);
8570 Adjust_Result_Type (N, Typ);
8573 Rewrite_Comparison (N);
8575 -- For all cases other than elementary types, we rewrite node as the
8576 -- negation of an equality operation, and reanalyze. The equality to be
8577 -- used is defined in the same scope and has the same signature. This
8578 -- signature must be set explicitly since in an instance it may not have
8579 -- the same visibility as in the generic unit. This avoids duplicating
8580 -- or factoring the complex code for record/array equality tests etc.
8584 Loc : constant Source_Ptr := Sloc (N);
8586 Ne : constant Entity_Id := Entity (N);
8589 Binary_Op_Validity_Checks (N);
8595 Left_Opnd => Left_Opnd (N),
8596 Right_Opnd => Right_Opnd (N)));
8597 Set_Paren_Count (Right_Opnd (Neg), 1);
8599 if Scope (Ne) /= Standard_Standard then
8600 Set_Entity (Right_Opnd (Neg), Corresponding_Equality (Ne));
8603 -- For navigation purposes, we want to treat the inequality as an
8604 -- implicit reference to the corresponding equality. Preserve the
8605 -- Comes_From_ source flag to generate proper Xref entries.
8607 Preserve_Comes_From_Source (Neg, N);
8608 Preserve_Comes_From_Source (Right_Opnd (Neg), N);
8610 Analyze_And_Resolve (N, Standard_Boolean);
8614 Optimize_Length_Comparison (N);
8617 ---------------------
8618 -- Expand_N_Op_Not --
8619 ---------------------
8621 -- If the argument is other than a Boolean array type, there is no special
8622 -- expansion required, except for dealing with validity checks, and non-
8623 -- standard boolean representations.
8625 -- For the packed array case, we call the special routine in Exp_Pakd,
8626 -- except that if the component size is greater than one, we use the
8627 -- standard routine generating a gruesome loop (it is so peculiar to have
8628 -- packed arrays with non-standard Boolean representations anyway, so it
8629 -- does not matter that we do not handle this case efficiently).
8631 -- For the unpacked array case (and for the special packed case where we
8632 -- have non standard Booleans, as discussed above), we generate and insert
8633 -- into the tree the following function definition:
8635 -- function Nnnn (A : arr) is
8638 -- for J in a'range loop
8639 -- B (J) := not A (J);
8644 -- Here arr is the actual subtype of the parameter (and hence always
8645 -- constrained). Then we replace the not with a call to this function.
8647 procedure Expand_N_Op_Not (N : Node_Id) is
8648 Loc : constant Source_Ptr := Sloc (N);
8649 Typ : constant Entity_Id := Etype (N);
8658 Func_Name : Entity_Id;
8659 Loop_Statement : Node_Id;
8662 Unary_Op_Validity_Checks (N);
8664 -- For boolean operand, deal with non-standard booleans
8666 if Is_Boolean_Type (Typ) then
8667 Adjust_Condition (Right_Opnd (N));
8668 Set_Etype (N, Standard_Boolean);
8669 Adjust_Result_Type (N, Typ);
8673 -- Only array types need any other processing
8675 if not Is_Array_Type (Typ) then
8679 -- Case of array operand. If bit packed with a component size of 1,
8680 -- handle it in Exp_Pakd if the operand is known to be aligned.
8682 if Is_Bit_Packed_Array (Typ)
8683 and then Component_Size (Typ) = 1
8684 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
8686 Expand_Packed_Not (N);
8690 -- Case of array operand which is not bit-packed. If the context is
8691 -- a safe assignment, call in-place operation, If context is a larger
8692 -- boolean expression in the context of a safe assignment, expansion is
8693 -- done by enclosing operation.
8695 Opnd := Relocate_Node (Right_Opnd (N));
8696 Convert_To_Actual_Subtype (Opnd);
8697 Arr := Etype (Opnd);
8698 Ensure_Defined (Arr, N);
8699 Silly_Boolean_Array_Not_Test (N, Arr);
8701 if Nkind (Parent (N)) = N_Assignment_Statement then
8702 if Safe_In_Place_Array_Op (Name (Parent (N)), N, Empty) then
8703 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
8706 -- Special case the negation of a binary operation
8708 elsif Nkind_In (Opnd, N_Op_And, N_Op_Or, N_Op_Xor)
8709 and then Safe_In_Place_Array_Op
8710 (Name (Parent (N)), Left_Opnd (Opnd), Right_Opnd (Opnd))
8712 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
8716 elsif Nkind (Parent (N)) in N_Binary_Op
8717 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
8720 Op1 : constant Node_Id := Left_Opnd (Parent (N));
8721 Op2 : constant Node_Id := Right_Opnd (Parent (N));
8722 Lhs : constant Node_Id := Name (Parent (Parent (N)));
8725 if Safe_In_Place_Array_Op (Lhs, Op1, Op2) then
8727 -- (not A) op (not B) can be reduced to a single call
8729 if N = Op1 and then Nkind (Op2) = N_Op_Not then
8732 elsif N = Op2 and then Nkind (Op1) = N_Op_Not then
8735 -- A xor (not B) can also be special-cased
8737 elsif N = Op2 and then Nkind (Parent (N)) = N_Op_Xor then
8744 A := Make_Defining_Identifier (Loc, Name_uA);
8745 B := Make_Defining_Identifier (Loc, Name_uB);
8746 J := Make_Defining_Identifier (Loc, Name_uJ);
8749 Make_Indexed_Component (Loc,
8750 Prefix => New_Occurrence_Of (A, Loc),
8751 Expressions => New_List (New_Occurrence_Of (J, Loc)));
8754 Make_Indexed_Component (Loc,
8755 Prefix => New_Occurrence_Of (B, Loc),
8756 Expressions => New_List (New_Occurrence_Of (J, Loc)));
8759 Make_Implicit_Loop_Statement (N,
8760 Identifier => Empty,
8763 Make_Iteration_Scheme (Loc,
8764 Loop_Parameter_Specification =>
8765 Make_Loop_Parameter_Specification (Loc,
8766 Defining_Identifier => J,
8767 Discrete_Subtype_Definition =>
8768 Make_Attribute_Reference (Loc,
8769 Prefix => Make_Identifier (Loc, Chars (A)),
8770 Attribute_Name => Name_Range))),
8772 Statements => New_List (
8773 Make_Assignment_Statement (Loc,
8775 Expression => Make_Op_Not (Loc, A_J))));
8777 Func_Name := Make_Temporary (Loc, 'N');
8778 Set_Is_Inlined (Func_Name);
8781 Make_Subprogram_Body (Loc,
8783 Make_Function_Specification (Loc,
8784 Defining_Unit_Name => Func_Name,
8785 Parameter_Specifications => New_List (
8786 Make_Parameter_Specification (Loc,
8787 Defining_Identifier => A,
8788 Parameter_Type => New_Occurrence_Of (Typ, Loc))),
8789 Result_Definition => New_Occurrence_Of (Typ, Loc)),
8791 Declarations => New_List (
8792 Make_Object_Declaration (Loc,
8793 Defining_Identifier => B,
8794 Object_Definition => New_Occurrence_Of (Arr, Loc))),
8796 Handled_Statement_Sequence =>
8797 Make_Handled_Sequence_Of_Statements (Loc,
8798 Statements => New_List (
8800 Make_Simple_Return_Statement (Loc,
8801 Expression => Make_Identifier (Loc, Chars (B)))))));
8804 Make_Function_Call (Loc,
8805 Name => New_Occurrence_Of (Func_Name, Loc),
8806 Parameter_Associations => New_List (Opnd)));
8808 Analyze_And_Resolve (N, Typ);
8809 end Expand_N_Op_Not;
8811 --------------------
8812 -- Expand_N_Op_Or --
8813 --------------------
8815 procedure Expand_N_Op_Or (N : Node_Id) is
8816 Typ : constant Entity_Id := Etype (N);
8819 Binary_Op_Validity_Checks (N);
8821 if Is_Array_Type (Etype (N)) then
8822 Expand_Boolean_Operator (N);
8824 elsif Is_Boolean_Type (Etype (N)) then
8825 Adjust_Condition (Left_Opnd (N));
8826 Adjust_Condition (Right_Opnd (N));
8827 Set_Etype (N, Standard_Boolean);
8828 Adjust_Result_Type (N, Typ);
8830 elsif Is_Intrinsic_Subprogram (Entity (N)) then
8831 Expand_Intrinsic_Call (N, Entity (N));
8836 ----------------------
8837 -- Expand_N_Op_Plus --
8838 ----------------------
8840 procedure Expand_N_Op_Plus (N : Node_Id) is
8842 Unary_Op_Validity_Checks (N);
8844 -- Check for MINIMIZED/ELIMINATED overflow mode
8846 if Minimized_Eliminated_Overflow_Check (N) then
8847 Apply_Arithmetic_Overflow_Check (N);
8850 end Expand_N_Op_Plus;
8852 ---------------------
8853 -- Expand_N_Op_Rem --
8854 ---------------------
8856 procedure Expand_N_Op_Rem (N : Node_Id) is
8857 Loc : constant Source_Ptr := Sloc (N);
8858 Typ : constant Entity_Id := Etype (N);
8869 -- Set if corresponding operand can be negative
8871 pragma Unreferenced (Hi);
8874 Binary_Op_Validity_Checks (N);
8876 -- Check for MINIMIZED/ELIMINATED overflow mode
8878 if Minimized_Eliminated_Overflow_Check (N) then
8879 Apply_Arithmetic_Overflow_Check (N);
8883 if Is_Integer_Type (Etype (N)) then
8884 Apply_Divide_Checks (N);
8886 -- All done if we don't have a REM any more, which can happen as a
8887 -- result of overflow expansion in MINIMIZED or ELIMINATED modes.
8889 if Nkind (N) /= N_Op_Rem then
8894 -- Proceed with expansion of REM
8896 Left := Left_Opnd (N);
8897 Right := Right_Opnd (N);
8899 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
8900 -- but it is useful with other back ends (e.g. AAMP), and is certainly
8903 if Is_Integer_Type (Etype (N))
8904 and then Compile_Time_Known_Value (Right)
8905 and then Expr_Value (Right) = Uint_1
8907 -- Call Remove_Side_Effects to ensure that any side effects in the
8908 -- ignored left operand (in particular function calls to user defined
8909 -- functions) are properly executed.
8911 Remove_Side_Effects (Left);
8913 Rewrite (N, Make_Integer_Literal (Loc, 0));
8914 Analyze_And_Resolve (N, Typ);
8918 -- Deal with annoying case of largest negative number remainder minus
8919 -- one. Gigi may not handle this case correctly, because on some
8920 -- targets, the mod value is computed using a divide instruction
8921 -- which gives an overflow trap for this case.
8923 -- It would be a bit more efficient to figure out which targets this
8924 -- is really needed for, but in practice it is reasonable to do the
8925 -- following special check in all cases, since it means we get a clearer
8926 -- message, and also the overhead is minimal given that division is
8927 -- expensive in any case.
8929 -- In fact the check is quite easy, if the right operand is -1, then
8930 -- the remainder is always 0, and we can just ignore the left operand
8931 -- completely in this case.
8933 Determine_Range (Right, OK, Lo, Hi, Assume_Valid => True);
8934 Lneg := (not OK) or else Lo < 0;
8936 Determine_Range (Left, OK, Lo, Hi, Assume_Valid => True);
8937 Rneg := (not OK) or else Lo < 0;
8939 -- We won't mess with trying to find out if the left operand can really
8940 -- be the largest negative number (that's a pain in the case of private
8941 -- types and this is really marginal). We will just assume that we need
8942 -- the test if the left operand can be negative at all.
8944 if Lneg and Rneg then
8946 Make_If_Expression (Loc,
8947 Expressions => New_List (
8949 Left_Opnd => Duplicate_Subexpr (Right),
8951 Unchecked_Convert_To (Typ, Make_Integer_Literal (Loc, -1))),
8953 Unchecked_Convert_To (Typ,
8954 Make_Integer_Literal (Loc, Uint_0)),
8956 Relocate_Node (N))));
8958 Set_Analyzed (Next (Next (First (Expressions (N)))));
8959 Analyze_And_Resolve (N, Typ);
8961 end Expand_N_Op_Rem;
8963 -----------------------------
8964 -- Expand_N_Op_Rotate_Left --
8965 -----------------------------
8967 procedure Expand_N_Op_Rotate_Left (N : Node_Id) is
8969 Binary_Op_Validity_Checks (N);
8971 -- If we are in Modify_Tree_For_C mode, there is no rotate left in C,
8972 -- so we rewrite in terms of logical shifts
8974 -- Shift_Left (Num, Bits) or Shift_Right (num, Esize - Bits)
8976 -- where Bits is the shift count mod Esize (the mod operation here
8977 -- deals with ludicrous large shift counts, which are apparently OK).
8979 -- What about non-binary modulus ???
8982 Loc : constant Source_Ptr := Sloc (N);
8983 Rtp : constant Entity_Id := Etype (Right_Opnd (N));
8984 Typ : constant Entity_Id := Etype (N);
8987 if Modify_Tree_For_C then
8988 Rewrite (Right_Opnd (N),
8990 Left_Opnd => Relocate_Node (Right_Opnd (N)),
8991 Right_Opnd => Make_Integer_Literal (Loc, Esize (Typ))));
8993 Analyze_And_Resolve (Right_Opnd (N), Rtp);
8998 Make_Op_Shift_Left (Loc,
8999 Left_Opnd => Left_Opnd (N),
9000 Right_Opnd => Right_Opnd (N)),
9003 Make_Op_Shift_Right (Loc,
9004 Left_Opnd => Duplicate_Subexpr_No_Checks (Left_Opnd (N)),
9006 Make_Op_Subtract (Loc,
9007 Left_Opnd => Make_Integer_Literal (Loc, Esize (Typ)),
9009 Duplicate_Subexpr_No_Checks (Right_Opnd (N))))));
9011 Analyze_And_Resolve (N, Typ);
9014 end Expand_N_Op_Rotate_Left;
9016 ------------------------------
9017 -- Expand_N_Op_Rotate_Right --
9018 ------------------------------
9020 procedure Expand_N_Op_Rotate_Right (N : Node_Id) is
9022 Binary_Op_Validity_Checks (N);
9024 -- If we are in Modify_Tree_For_C mode, there is no rotate right in C,
9025 -- so we rewrite in terms of logical shifts
9027 -- Shift_Right (Num, Bits) or Shift_Left (num, Esize - Bits)
9029 -- where Bits is the shift count mod Esize (the mod operation here
9030 -- deals with ludicrous large shift counts, which are apparently OK).
9032 -- What about non-binary modulus ???
9035 Loc : constant Source_Ptr := Sloc (N);
9036 Rtp : constant Entity_Id := Etype (Right_Opnd (N));
9037 Typ : constant Entity_Id := Etype (N);
9040 Rewrite (Right_Opnd (N),
9042 Left_Opnd => Relocate_Node (Right_Opnd (N)),
9043 Right_Opnd => Make_Integer_Literal (Loc, Esize (Typ))));
9045 Analyze_And_Resolve (Right_Opnd (N), Rtp);
9047 if Modify_Tree_For_C then
9051 Make_Op_Shift_Right (Loc,
9052 Left_Opnd => Left_Opnd (N),
9053 Right_Opnd => Right_Opnd (N)),
9056 Make_Op_Shift_Left (Loc,
9057 Left_Opnd => Duplicate_Subexpr_No_Checks (Left_Opnd (N)),
9059 Make_Op_Subtract (Loc,
9060 Left_Opnd => Make_Integer_Literal (Loc, Esize (Typ)),
9062 Duplicate_Subexpr_No_Checks (Right_Opnd (N))))));
9064 Analyze_And_Resolve (N, Typ);
9067 end Expand_N_Op_Rotate_Right;
9069 ----------------------------
9070 -- Expand_N_Op_Shift_Left --
9071 ----------------------------
9073 -- Note: nothing in this routine depends on left as opposed to right shifts
9074 -- so we share the routine for expanding shift right operations.
9076 procedure Expand_N_Op_Shift_Left (N : Node_Id) is
9078 Binary_Op_Validity_Checks (N);
9080 -- If we are in Modify_Tree_For_C mode, then ensure that the right
9081 -- operand is not greater than the word size (since that would not
9082 -- be defined properly by the corresponding C shift operator).
9084 if Modify_Tree_For_C then
9086 Right : constant Node_Id := Right_Opnd (N);
9087 Loc : constant Source_Ptr := Sloc (Right);
9088 Typ : constant Entity_Id := Etype (N);
9089 Siz : constant Uint := Esize (Typ);
9096 if Compile_Time_Known_Value (Right) then
9097 if Expr_Value (Right) >= Siz then
9098 Rewrite (N, Make_Integer_Literal (Loc, 0));
9099 Analyze_And_Resolve (N, Typ);
9102 -- Not compile time known, find range
9105 Determine_Range (Right, OK, Lo, Hi, Assume_Valid => True);
9107 -- Nothing to do if known to be OK range, otherwise expand
9109 if not OK or else Hi >= Siz then
9111 -- Prevent recursion on copy of shift node
9113 Orig := Relocate_Node (N);
9114 Set_Analyzed (Orig);
9116 -- Now do the rewrite
9119 Make_If_Expression (Loc,
9120 Expressions => New_List (
9122 Left_Opnd => Duplicate_Subexpr_Move_Checks (Right),
9123 Right_Opnd => Make_Integer_Literal (Loc, Siz)),
9124 Make_Integer_Literal (Loc, 0),
9126 Analyze_And_Resolve (N, Typ);
9131 end Expand_N_Op_Shift_Left;
9133 -----------------------------
9134 -- Expand_N_Op_Shift_Right --
9135 -----------------------------
9137 procedure Expand_N_Op_Shift_Right (N : Node_Id) is
9139 -- Share shift left circuit
9141 Expand_N_Op_Shift_Left (N);
9142 end Expand_N_Op_Shift_Right;
9144 ----------------------------------------
9145 -- Expand_N_Op_Shift_Right_Arithmetic --
9146 ----------------------------------------
9148 procedure Expand_N_Op_Shift_Right_Arithmetic (N : Node_Id) is
9150 Binary_Op_Validity_Checks (N);
9152 -- If we are in Modify_Tree_For_C mode, there is no shift right
9153 -- arithmetic in C, so we rewrite in terms of logical shifts.
9155 -- Shift_Right (Num, Bits) or
9157 -- then not (Shift_Right (Mask, bits))
9160 -- Here Mask is all 1 bits (2**size - 1), and Sign is 2**(size - 1)
9162 -- Note: in almost all C compilers it would work to just shift a
9163 -- signed integer right, but it's undefined and we cannot rely on it.
9165 -- Note: the above works fine for shift counts greater than or equal
9166 -- to the word size, since in this case (not (Shift_Right (Mask, bits)))
9167 -- generates all 1'bits.
9169 -- What about non-binary modulus ???
9172 Loc : constant Source_Ptr := Sloc (N);
9173 Typ : constant Entity_Id := Etype (N);
9174 Sign : constant Uint := 2 ** (Esize (Typ) - 1);
9175 Mask : constant Uint := (2 ** Esize (Typ)) - 1;
9176 Left : constant Node_Id := Left_Opnd (N);
9177 Right : constant Node_Id := Right_Opnd (N);
9181 if Modify_Tree_For_C then
9183 -- Here if not (Shift_Right (Mask, bits)) can be computed at
9184 -- compile time as a single constant.
9186 if Compile_Time_Known_Value (Right) then
9188 Val : constant Uint := Expr_Value (Right);
9191 if Val >= Esize (Typ) then
9192 Maskx := Make_Integer_Literal (Loc, Mask);
9196 Make_Integer_Literal (Loc,
9197 Intval => Mask - (Mask / (2 ** Expr_Value (Right))));
9205 Make_Op_Shift_Right (Loc,
9206 Left_Opnd => Make_Integer_Literal (Loc, Mask),
9207 Right_Opnd => Duplicate_Subexpr_No_Checks (Right)));
9210 -- Now do the rewrite
9215 Make_Op_Shift_Right (Loc,
9217 Right_Opnd => Right),
9219 Make_If_Expression (Loc,
9220 Expressions => New_List (
9222 Left_Opnd => Duplicate_Subexpr_No_Checks (Left),
9223 Right_Opnd => Make_Integer_Literal (Loc, Sign)),
9225 Make_Integer_Literal (Loc, 0)))));
9226 Analyze_And_Resolve (N, Typ);
9229 end Expand_N_Op_Shift_Right_Arithmetic;
9231 --------------------------
9232 -- Expand_N_Op_Subtract --
9233 --------------------------
9235 procedure Expand_N_Op_Subtract (N : Node_Id) is
9236 Typ : constant Entity_Id := Etype (N);
9239 Binary_Op_Validity_Checks (N);
9241 -- Check for MINIMIZED/ELIMINATED overflow mode
9243 if Minimized_Eliminated_Overflow_Check (N) then
9244 Apply_Arithmetic_Overflow_Check (N);
9248 -- N - 0 = N for integer types
9250 if Is_Integer_Type (Typ)
9251 and then Compile_Time_Known_Value (Right_Opnd (N))
9252 and then Expr_Value (Right_Opnd (N)) = 0
9254 Rewrite (N, Left_Opnd (N));
9258 -- Arithmetic overflow checks for signed integer/fixed point types
9260 if Is_Signed_Integer_Type (Typ) or else Is_Fixed_Point_Type (Typ) then
9261 Apply_Arithmetic_Overflow_Check (N);
9264 -- Overflow checks for floating-point if -gnateF mode active
9266 Check_Float_Op_Overflow (N);
9267 end Expand_N_Op_Subtract;
9269 ---------------------
9270 -- Expand_N_Op_Xor --
9271 ---------------------
9273 procedure Expand_N_Op_Xor (N : Node_Id) is
9274 Typ : constant Entity_Id := Etype (N);
9277 Binary_Op_Validity_Checks (N);
9279 if Is_Array_Type (Etype (N)) then
9280 Expand_Boolean_Operator (N);
9282 elsif Is_Boolean_Type (Etype (N)) then
9283 Adjust_Condition (Left_Opnd (N));
9284 Adjust_Condition (Right_Opnd (N));
9285 Set_Etype (N, Standard_Boolean);
9286 Adjust_Result_Type (N, Typ);
9288 elsif Is_Intrinsic_Subprogram (Entity (N)) then
9289 Expand_Intrinsic_Call (N, Entity (N));
9292 end Expand_N_Op_Xor;
9294 ----------------------
9295 -- Expand_N_Or_Else --
9296 ----------------------
9298 procedure Expand_N_Or_Else (N : Node_Id)
9299 renames Expand_Short_Circuit_Operator;
9301 -----------------------------------
9302 -- Expand_N_Qualified_Expression --
9303 -----------------------------------
9305 procedure Expand_N_Qualified_Expression (N : Node_Id) is
9306 Operand : constant Node_Id := Expression (N);
9307 Target_Type : constant Entity_Id := Entity (Subtype_Mark (N));
9310 -- Do validity check if validity checking operands
9312 if Validity_Checks_On and Validity_Check_Operands then
9313 Ensure_Valid (Operand);
9316 -- Apply possible constraint check
9318 Apply_Constraint_Check (Operand, Target_Type, No_Sliding => True);
9320 if Do_Range_Check (Operand) then
9321 Set_Do_Range_Check (Operand, False);
9322 Generate_Range_Check (Operand, Target_Type, CE_Range_Check_Failed);
9324 end Expand_N_Qualified_Expression;
9326 ------------------------------------
9327 -- Expand_N_Quantified_Expression --
9328 ------------------------------------
9332 -- for all X in range => Cond
9337 -- for X in range loop
9344 -- Similarly, an existentially quantified expression:
9346 -- for some X in range => Cond
9351 -- for X in range loop
9358 -- In both cases, the iteration may be over a container in which case it is
9359 -- given by an iterator specification, not a loop parameter specification.
9361 procedure Expand_N_Quantified_Expression (N : Node_Id) is
9362 Actions : constant List_Id := New_List;
9363 For_All : constant Boolean := All_Present (N);
9364 Iter_Spec : constant Node_Id := Iterator_Specification (N);
9365 Loc : constant Source_Ptr := Sloc (N);
9366 Loop_Spec : constant Node_Id := Loop_Parameter_Specification (N);
9373 -- Create the declaration of the flag which tracks the status of the
9374 -- quantified expression. Generate:
9376 -- Flag : Boolean := (True | False);
9378 Flag := Make_Temporary (Loc, 'T', N);
9381 Make_Object_Declaration (Loc,
9382 Defining_Identifier => Flag,
9383 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc),
9385 New_Occurrence_Of (Boolean_Literals (For_All), Loc)));
9387 -- Construct the circuitry which tracks the status of the quantified
9388 -- expression. Generate:
9390 -- if [not] Cond then
9391 -- Flag := (False | True);
9395 Cond := Relocate_Node (Condition (N));
9398 Cond := Make_Op_Not (Loc, Cond);
9402 Make_Implicit_If_Statement (N,
9404 Then_Statements => New_List (
9405 Make_Assignment_Statement (Loc,
9406 Name => New_Occurrence_Of (Flag, Loc),
9408 New_Occurrence_Of (Boolean_Literals (not For_All), Loc)),
9409 Make_Exit_Statement (Loc))));
9411 -- Build the loop equivalent of the quantified expression
9413 if Present (Iter_Spec) then
9415 Make_Iteration_Scheme (Loc,
9416 Iterator_Specification => Iter_Spec);
9419 Make_Iteration_Scheme (Loc,
9420 Loop_Parameter_Specification => Loop_Spec);
9424 Make_Loop_Statement (Loc,
9425 Iteration_Scheme => Scheme,
9426 Statements => Stmts,
9427 End_Label => Empty));
9429 -- Transform the quantified expression
9432 Make_Expression_With_Actions (Loc,
9433 Expression => New_Occurrence_Of (Flag, Loc),
9434 Actions => Actions));
9435 Analyze_And_Resolve (N, Standard_Boolean);
9436 end Expand_N_Quantified_Expression;
9438 ---------------------------------
9439 -- Expand_N_Selected_Component --
9440 ---------------------------------
9442 procedure Expand_N_Selected_Component (N : Node_Id) is
9443 Loc : constant Source_Ptr := Sloc (N);
9444 Par : constant Node_Id := Parent (N);
9445 P : constant Node_Id := Prefix (N);
9446 S : constant Node_Id := Selector_Name (N);
9447 Ptyp : Entity_Id := Underlying_Type (Etype (P));
9453 function In_Left_Hand_Side (Comp : Node_Id) return Boolean;
9454 -- Gigi needs a temporary for prefixes that depend on a discriminant,
9455 -- unless the context of an assignment can provide size information.
9456 -- Don't we have a general routine that does this???
9458 function Is_Subtype_Declaration return Boolean;
9459 -- The replacement of a discriminant reference by its value is required
9460 -- if this is part of the initialization of an temporary generated by a
9461 -- change of representation. This shows up as the construction of a
9462 -- discriminant constraint for a subtype declared at the same point as
9463 -- the entity in the prefix of the selected component. We recognize this
9464 -- case when the context of the reference is:
9465 -- subtype ST is T(Obj.D);
9466 -- where the entity for Obj comes from source, and ST has the same sloc.
9468 -----------------------
9469 -- In_Left_Hand_Side --
9470 -----------------------
9472 function In_Left_Hand_Side (Comp : Node_Id) return Boolean is
9474 return (Nkind (Parent (Comp)) = N_Assignment_Statement
9475 and then Comp = Name (Parent (Comp)))
9476 or else (Present (Parent (Comp))
9477 and then Nkind (Parent (Comp)) in N_Subexpr
9478 and then In_Left_Hand_Side (Parent (Comp)));
9479 end In_Left_Hand_Side;
9481 -----------------------------
9482 -- Is_Subtype_Declaration --
9483 -----------------------------
9485 function Is_Subtype_Declaration return Boolean is
9486 Par : constant Node_Id := Parent (N);
9489 Nkind (Par) = N_Index_Or_Discriminant_Constraint
9490 and then Nkind (Parent (Parent (Par))) = N_Subtype_Declaration
9491 and then Comes_From_Source (Entity (Prefix (N)))
9492 and then Sloc (Par) = Sloc (Entity (Prefix (N)));
9493 end Is_Subtype_Declaration;
9495 -- Start of processing for Expand_N_Selected_Component
9498 -- Insert explicit dereference if required
9500 if Is_Access_Type (Ptyp) then
9502 -- First set prefix type to proper access type, in case it currently
9503 -- has a private (non-access) view of this type.
9505 Set_Etype (P, Ptyp);
9507 Insert_Explicit_Dereference (P);
9508 Analyze_And_Resolve (P, Designated_Type (Ptyp));
9510 if Ekind (Etype (P)) = E_Private_Subtype
9511 and then Is_For_Access_Subtype (Etype (P))
9513 Set_Etype (P, Base_Type (Etype (P)));
9519 -- Deal with discriminant check required
9521 if Do_Discriminant_Check (N) then
9522 if Present (Discriminant_Checking_Func
9523 (Original_Record_Component (Entity (S))))
9525 -- Present the discriminant checking function to the backend, so
9526 -- that it can inline the call to the function.
9529 (Discriminant_Checking_Func
9530 (Original_Record_Component (Entity (S))));
9532 -- Now reset the flag and generate the call
9534 Set_Do_Discriminant_Check (N, False);
9535 Generate_Discriminant_Check (N);
9537 -- In the case of Unchecked_Union, no discriminant checking is
9538 -- actually performed.
9541 Set_Do_Discriminant_Check (N, False);
9545 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
9546 -- function, then additional actuals must be passed.
9548 if Ada_Version >= Ada_2005
9549 and then Is_Build_In_Place_Function_Call (P)
9551 Make_Build_In_Place_Call_In_Anonymous_Context (P);
9554 -- Gigi cannot handle unchecked conversions that are the prefix of a
9555 -- selected component with discriminants. This must be checked during
9556 -- expansion, because during analysis the type of the selector is not
9557 -- known at the point the prefix is analyzed. If the conversion is the
9558 -- target of an assignment, then we cannot force the evaluation.
9560 if Nkind (Prefix (N)) = N_Unchecked_Type_Conversion
9561 and then Has_Discriminants (Etype (N))
9562 and then not In_Left_Hand_Side (N)
9564 Force_Evaluation (Prefix (N));
9567 -- Remaining processing applies only if selector is a discriminant
9569 if Ekind (Entity (Selector_Name (N))) = E_Discriminant then
9571 -- If the selector is a discriminant of a constrained record type,
9572 -- we may be able to rewrite the expression with the actual value
9573 -- of the discriminant, a useful optimization in some cases.
9575 if Is_Record_Type (Ptyp)
9576 and then Has_Discriminants (Ptyp)
9577 and then Is_Constrained (Ptyp)
9579 -- Do this optimization for discrete types only, and not for
9580 -- access types (access discriminants get us into trouble).
9582 if not Is_Discrete_Type (Etype (N)) then
9585 -- Don't do this on the left hand of an assignment statement.
9586 -- Normally one would think that references like this would not
9587 -- occur, but they do in generated code, and mean that we really
9588 -- do want to assign the discriminant.
9590 elsif Nkind (Par) = N_Assignment_Statement
9591 and then Name (Par) = N
9595 -- Don't do this optimization for the prefix of an attribute or
9596 -- the name of an object renaming declaration since these are
9597 -- contexts where we do not want the value anyway.
9599 elsif (Nkind (Par) = N_Attribute_Reference
9600 and then Prefix (Par) = N)
9601 or else Is_Renamed_Object (N)
9605 -- Don't do this optimization if we are within the code for a
9606 -- discriminant check, since the whole point of such a check may
9607 -- be to verify the condition on which the code below depends.
9609 elsif Is_In_Discriminant_Check (N) then
9612 -- Green light to see if we can do the optimization. There is
9613 -- still one condition that inhibits the optimization below but
9614 -- now is the time to check the particular discriminant.
9617 -- Loop through discriminants to find the matching discriminant
9618 -- constraint to see if we can copy it.
9620 Disc := First_Discriminant (Ptyp);
9621 Dcon := First_Elmt (Discriminant_Constraint (Ptyp));
9622 Discr_Loop : while Present (Dcon) loop
9623 Dval := Node (Dcon);
9625 -- Check if this is the matching discriminant and if the
9626 -- discriminant value is simple enough to make sense to
9627 -- copy. We don't want to copy complex expressions, and
9628 -- indeed to do so can cause trouble (before we put in
9629 -- this guard, a discriminant expression containing an
9630 -- AND THEN was copied, causing problems for coverage
9633 -- However, if the reference is part of the initialization
9634 -- code generated for an object declaration, we must use
9635 -- the discriminant value from the subtype constraint,
9636 -- because the selected component may be a reference to the
9637 -- object being initialized, whose discriminant is not yet
9638 -- set. This only happens in complex cases involving changes
9639 -- or representation.
9641 if Disc = Entity (Selector_Name (N))
9642 and then (Is_Entity_Name (Dval)
9643 or else Compile_Time_Known_Value (Dval)
9644 or else Is_Subtype_Declaration)
9646 -- Here we have the matching discriminant. Check for
9647 -- the case of a discriminant of a component that is
9648 -- constrained by an outer discriminant, which cannot
9649 -- be optimized away.
9651 if Denotes_Discriminant
9652 (Dval, Check_Concurrent => True)
9656 elsif Nkind (Original_Node (Dval)) = N_Selected_Component
9658 Denotes_Discriminant
9659 (Selector_Name (Original_Node (Dval)), True)
9663 -- Do not retrieve value if constraint is not static. It
9664 -- is generally not useful, and the constraint may be a
9665 -- rewritten outer discriminant in which case it is in
9668 elsif Is_Entity_Name (Dval)
9670 Nkind (Parent (Entity (Dval))) = N_Object_Declaration
9671 and then Present (Expression (Parent (Entity (Dval))))
9673 Is_OK_Static_Expression
9674 (Expression (Parent (Entity (Dval))))
9678 -- In the context of a case statement, the expression may
9679 -- have the base type of the discriminant, and we need to
9680 -- preserve the constraint to avoid spurious errors on
9683 elsif Nkind (Parent (N)) = N_Case_Statement
9684 and then Etype (Dval) /= Etype (Disc)
9687 Make_Qualified_Expression (Loc,
9689 New_Occurrence_Of (Etype (Disc), Loc),
9691 New_Copy_Tree (Dval)));
9692 Analyze_And_Resolve (N, Etype (Disc));
9694 -- In case that comes out as a static expression,
9695 -- reset it (a selected component is never static).
9697 Set_Is_Static_Expression (N, False);
9700 -- Otherwise we can just copy the constraint, but the
9701 -- result is certainly not static. In some cases the
9702 -- discriminant constraint has been analyzed in the
9703 -- context of the original subtype indication, but for
9704 -- itypes the constraint might not have been analyzed
9705 -- yet, and this must be done now.
9708 Rewrite (N, New_Copy_Tree (Dval));
9709 Analyze_And_Resolve (N);
9710 Set_Is_Static_Expression (N, False);
9716 Next_Discriminant (Disc);
9717 end loop Discr_Loop;
9719 -- Note: the above loop should always find a matching
9720 -- discriminant, but if it does not, we just missed an
9721 -- optimization due to some glitch (perhaps a previous
9722 -- error), so ignore.
9727 -- The only remaining processing is in the case of a discriminant of
9728 -- a concurrent object, where we rewrite the prefix to denote the
9729 -- corresponding record type. If the type is derived and has renamed
9730 -- discriminants, use corresponding discriminant, which is the one
9731 -- that appears in the corresponding record.
9733 if not Is_Concurrent_Type (Ptyp) then
9737 Disc := Entity (Selector_Name (N));
9739 if Is_Derived_Type (Ptyp)
9740 and then Present (Corresponding_Discriminant (Disc))
9742 Disc := Corresponding_Discriminant (Disc);
9746 Make_Selected_Component (Loc,
9748 Unchecked_Convert_To (Corresponding_Record_Type (Ptyp),
9750 Selector_Name => Make_Identifier (Loc, Chars (Disc)));
9756 -- Set Atomic_Sync_Required if necessary for atomic component
9758 if Nkind (N) = N_Selected_Component then
9760 E : constant Entity_Id := Entity (Selector_Name (N));
9764 -- If component is atomic, but type is not, setting depends on
9765 -- disable/enable state for the component.
9767 if Is_Atomic (E) and then not Is_Atomic (Etype (E)) then
9768 Set := not Atomic_Synchronization_Disabled (E);
9770 -- If component is not atomic, but its type is atomic, setting
9771 -- depends on disable/enable state for the type.
9773 elsif not Is_Atomic (E) and then Is_Atomic (Etype (E)) then
9774 Set := not Atomic_Synchronization_Disabled (Etype (E));
9776 -- If both component and type are atomic, we disable if either
9777 -- component or its type have sync disabled.
9779 elsif Is_Atomic (E) and then Is_Atomic (Etype (E)) then
9780 Set := (not Atomic_Synchronization_Disabled (E))
9782 (not Atomic_Synchronization_Disabled (Etype (E)));
9788 -- Set flag if required
9791 Activate_Atomic_Synchronization (N);
9795 end Expand_N_Selected_Component;
9797 --------------------
9798 -- Expand_N_Slice --
9799 --------------------
9801 procedure Expand_N_Slice (N : Node_Id) is
9802 Loc : constant Source_Ptr := Sloc (N);
9803 Typ : constant Entity_Id := Etype (N);
9805 function Is_Procedure_Actual (N : Node_Id) return Boolean;
9806 -- Check whether the argument is an actual for a procedure call, in
9807 -- which case the expansion of a bit-packed slice is deferred until the
9808 -- call itself is expanded. The reason this is required is that we might
9809 -- have an IN OUT or OUT parameter, and the copy out is essential, and
9810 -- that copy out would be missed if we created a temporary here in
9811 -- Expand_N_Slice. Note that we don't bother to test specifically for an
9812 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
9813 -- is harmless to defer expansion in the IN case, since the call
9814 -- processing will still generate the appropriate copy in operation,
9815 -- which will take care of the slice.
9817 procedure Make_Temporary_For_Slice;
9818 -- Create a named variable for the value of the slice, in cases where
9819 -- the back-end cannot handle it properly, e.g. when packed types or
9820 -- unaligned slices are involved.
9822 -------------------------
9823 -- Is_Procedure_Actual --
9824 -------------------------
9826 function Is_Procedure_Actual (N : Node_Id) return Boolean is
9827 Par : Node_Id := Parent (N);
9831 -- If our parent is a procedure call we can return
9833 if Nkind (Par) = N_Procedure_Call_Statement then
9836 -- If our parent is a type conversion, keep climbing the tree,
9837 -- since a type conversion can be a procedure actual. Also keep
9838 -- climbing if parameter association or a qualified expression,
9839 -- since these are additional cases that do can appear on
9840 -- procedure actuals.
9842 elsif Nkind_In (Par, N_Type_Conversion,
9843 N_Parameter_Association,
9844 N_Qualified_Expression)
9846 Par := Parent (Par);
9848 -- Any other case is not what we are looking for
9854 end Is_Procedure_Actual;
9856 ------------------------------
9857 -- Make_Temporary_For_Slice --
9858 ------------------------------
9860 procedure Make_Temporary_For_Slice is
9861 Ent : constant Entity_Id := Make_Temporary (Loc, 'T', N);
9866 Make_Object_Declaration (Loc,
9867 Defining_Identifier => Ent,
9868 Object_Definition => New_Occurrence_Of (Typ, Loc));
9870 Set_No_Initialization (Decl);
9872 Insert_Actions (N, New_List (
9874 Make_Assignment_Statement (Loc,
9875 Name => New_Occurrence_Of (Ent, Loc),
9876 Expression => Relocate_Node (N))));
9878 Rewrite (N, New_Occurrence_Of (Ent, Loc));
9879 Analyze_And_Resolve (N, Typ);
9880 end Make_Temporary_For_Slice;
9884 Pref : constant Node_Id := Prefix (N);
9885 Pref_Typ : Entity_Id := Etype (Pref);
9887 -- Start of processing for Expand_N_Slice
9890 -- Special handling for access types
9892 if Is_Access_Type (Pref_Typ) then
9893 Pref_Typ := Designated_Type (Pref_Typ);
9896 Make_Explicit_Dereference (Sloc (N),
9897 Prefix => Relocate_Node (Pref)));
9899 Analyze_And_Resolve (Pref, Pref_Typ);
9902 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
9903 -- function, then additional actuals must be passed.
9905 if Ada_Version >= Ada_2005
9906 and then Is_Build_In_Place_Function_Call (Pref)
9908 Make_Build_In_Place_Call_In_Anonymous_Context (Pref);
9911 -- The remaining case to be handled is packed slices. We can leave
9912 -- packed slices as they are in the following situations:
9914 -- 1. Right or left side of an assignment (we can handle this
9915 -- situation correctly in the assignment statement expansion).
9917 -- 2. Prefix of indexed component (the slide is optimized away in this
9918 -- case, see the start of Expand_N_Slice.)
9920 -- 3. Object renaming declaration, since we want the name of the
9921 -- slice, not the value.
9923 -- 4. Argument to procedure call, since copy-in/copy-out handling may
9924 -- be required, and this is handled in the expansion of call
9927 -- 5. Prefix of an address attribute (this is an error which is caught
9928 -- elsewhere, and the expansion would interfere with generating the
9931 if not Is_Packed (Typ) then
9933 -- Apply transformation for actuals of a function call, where
9934 -- Expand_Actuals is not used.
9936 if Nkind (Parent (N)) = N_Function_Call
9937 and then Is_Possibly_Unaligned_Slice (N)
9939 Make_Temporary_For_Slice;
9942 elsif Nkind (Parent (N)) = N_Assignment_Statement
9943 or else (Nkind (Parent (Parent (N))) = N_Assignment_Statement
9944 and then Parent (N) = Name (Parent (Parent (N))))
9948 elsif Nkind (Parent (N)) = N_Indexed_Component
9949 or else Is_Renamed_Object (N)
9950 or else Is_Procedure_Actual (N)
9954 elsif Nkind (Parent (N)) = N_Attribute_Reference
9955 and then Attribute_Name (Parent (N)) = Name_Address
9960 Make_Temporary_For_Slice;
9964 ------------------------------
9965 -- Expand_N_Type_Conversion --
9966 ------------------------------
9968 procedure Expand_N_Type_Conversion (N : Node_Id) is
9969 Loc : constant Source_Ptr := Sloc (N);
9970 Operand : constant Node_Id := Expression (N);
9971 Target_Type : constant Entity_Id := Etype (N);
9972 Operand_Type : Entity_Id := Etype (Operand);
9974 procedure Handle_Changed_Representation;
9975 -- This is called in the case of record and array type conversions to
9976 -- see if there is a change of representation to be handled. Change of
9977 -- representation is actually handled at the assignment statement level,
9978 -- and what this procedure does is rewrite node N conversion as an
9979 -- assignment to temporary. If there is no change of representation,
9980 -- then the conversion node is unchanged.
9982 procedure Raise_Accessibility_Error;
9983 -- Called when we know that an accessibility check will fail. Rewrites
9984 -- node N to an appropriate raise statement and outputs warning msgs.
9985 -- The Etype of the raise node is set to Target_Type.
9987 procedure Real_Range_Check;
9988 -- Handles generation of range check for real target value
9990 function Has_Extra_Accessibility (Id : Entity_Id) return Boolean;
9991 -- True iff Present (Effective_Extra_Accessibility (Id)) successfully
9992 -- evaluates to True.
9994 -----------------------------------
9995 -- Handle_Changed_Representation --
9996 -----------------------------------
9998 procedure Handle_Changed_Representation is
10007 -- Nothing else to do if no change of representation
10009 if Same_Representation (Operand_Type, Target_Type) then
10012 -- The real change of representation work is done by the assignment
10013 -- statement processing. So if this type conversion is appearing as
10014 -- the expression of an assignment statement, nothing needs to be
10015 -- done to the conversion.
10017 elsif Nkind (Parent (N)) = N_Assignment_Statement then
10020 -- Otherwise we need to generate a temporary variable, and do the
10021 -- change of representation assignment into that temporary variable.
10022 -- The conversion is then replaced by a reference to this variable.
10027 -- If type is unconstrained we have to add a constraint, copied
10028 -- from the actual value of the left hand side.
10030 if not Is_Constrained (Target_Type) then
10031 if Has_Discriminants (Operand_Type) then
10032 Disc := First_Discriminant (Operand_Type);
10034 if Disc /= First_Stored_Discriminant (Operand_Type) then
10035 Disc := First_Stored_Discriminant (Operand_Type);
10039 while Present (Disc) loop
10041 Make_Selected_Component (Loc,
10043 Duplicate_Subexpr_Move_Checks (Operand),
10045 Make_Identifier (Loc, Chars (Disc))));
10046 Next_Discriminant (Disc);
10049 elsif Is_Array_Type (Operand_Type) then
10050 N_Ix := First_Index (Target_Type);
10053 for J in 1 .. Number_Dimensions (Operand_Type) loop
10055 -- We convert the bounds explicitly. We use an unchecked
10056 -- conversion because bounds checks are done elsewhere.
10061 Unchecked_Convert_To (Etype (N_Ix),
10062 Make_Attribute_Reference (Loc,
10064 Duplicate_Subexpr_No_Checks
10065 (Operand, Name_Req => True),
10066 Attribute_Name => Name_First,
10067 Expressions => New_List (
10068 Make_Integer_Literal (Loc, J)))),
10071 Unchecked_Convert_To (Etype (N_Ix),
10072 Make_Attribute_Reference (Loc,
10074 Duplicate_Subexpr_No_Checks
10075 (Operand, Name_Req => True),
10076 Attribute_Name => Name_Last,
10077 Expressions => New_List (
10078 Make_Integer_Literal (Loc, J))))));
10085 Odef := New_Occurrence_Of (Target_Type, Loc);
10087 if Present (Cons) then
10089 Make_Subtype_Indication (Loc,
10090 Subtype_Mark => Odef,
10092 Make_Index_Or_Discriminant_Constraint (Loc,
10093 Constraints => Cons));
10096 Temp := Make_Temporary (Loc, 'C');
10098 Make_Object_Declaration (Loc,
10099 Defining_Identifier => Temp,
10100 Object_Definition => Odef);
10102 Set_No_Initialization (Decl, True);
10104 -- Insert required actions. It is essential to suppress checks
10105 -- since we have suppressed default initialization, which means
10106 -- that the variable we create may have no discriminants.
10111 Make_Assignment_Statement (Loc,
10112 Name => New_Occurrence_Of (Temp, Loc),
10113 Expression => Relocate_Node (N))),
10114 Suppress => All_Checks);
10116 Rewrite (N, New_Occurrence_Of (Temp, Loc));
10119 end Handle_Changed_Representation;
10121 -------------------------------
10122 -- Raise_Accessibility_Error --
10123 -------------------------------
10125 procedure Raise_Accessibility_Error is
10127 Error_Msg_Warn := SPARK_Mode /= On;
10129 Make_Raise_Program_Error (Sloc (N),
10130 Reason => PE_Accessibility_Check_Failed));
10131 Set_Etype (N, Target_Type);
10133 Error_Msg_N ("<<accessibility check failure", N);
10134 Error_Msg_NE ("\<<& [", N, Standard_Program_Error);
10135 end Raise_Accessibility_Error;
10137 ----------------------
10138 -- Real_Range_Check --
10139 ----------------------
10141 -- Case of conversions to floating-point or fixed-point. If range checks
10142 -- are enabled and the target type has a range constraint, we convert:
10148 -- Tnn : typ'Base := typ'Base (x);
10149 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
10152 -- This is necessary when there is a conversion of integer to float or
10153 -- to fixed-point to ensure that the correct checks are made. It is not
10154 -- necessary for float to float where it is enough to simply set the
10155 -- Do_Range_Check flag.
10157 procedure Real_Range_Check is
10158 Btyp : constant Entity_Id := Base_Type (Target_Type);
10159 Lo : constant Node_Id := Type_Low_Bound (Target_Type);
10160 Hi : constant Node_Id := Type_High_Bound (Target_Type);
10161 Xtyp : constant Entity_Id := Etype (Operand);
10166 -- Nothing to do if conversion was rewritten
10168 if Nkind (N) /= N_Type_Conversion then
10172 -- Nothing to do if range checks suppressed, or target has the same
10173 -- range as the base type (or is the base type).
10175 if Range_Checks_Suppressed (Target_Type)
10176 or else (Lo = Type_Low_Bound (Btyp)
10178 Hi = Type_High_Bound (Btyp))
10183 -- Nothing to do if expression is an entity on which checks have been
10186 if Is_Entity_Name (Operand)
10187 and then Range_Checks_Suppressed (Entity (Operand))
10192 -- Nothing to do if bounds are all static and we can tell that the
10193 -- expression is within the bounds of the target. Note that if the
10194 -- operand is of an unconstrained floating-point type, then we do
10195 -- not trust it to be in range (might be infinite)
10198 S_Lo : constant Node_Id := Type_Low_Bound (Xtyp);
10199 S_Hi : constant Node_Id := Type_High_Bound (Xtyp);
10202 if (not Is_Floating_Point_Type (Xtyp)
10203 or else Is_Constrained (Xtyp))
10204 and then Compile_Time_Known_Value (S_Lo)
10205 and then Compile_Time_Known_Value (S_Hi)
10206 and then Compile_Time_Known_Value (Hi)
10207 and then Compile_Time_Known_Value (Lo)
10210 D_Lov : constant Ureal := Expr_Value_R (Lo);
10211 D_Hiv : constant Ureal := Expr_Value_R (Hi);
10216 if Is_Real_Type (Xtyp) then
10217 S_Lov := Expr_Value_R (S_Lo);
10218 S_Hiv := Expr_Value_R (S_Hi);
10220 S_Lov := UR_From_Uint (Expr_Value (S_Lo));
10221 S_Hiv := UR_From_Uint (Expr_Value (S_Hi));
10225 and then S_Lov >= D_Lov
10226 and then S_Hiv <= D_Hiv
10228 -- Unset the range check flag on the current value of
10229 -- Expression (N), since the captured Operand may have
10230 -- been rewritten (such as for the case of a conversion
10231 -- to a fixed-point type).
10233 Set_Do_Range_Check (Expression (N), False);
10241 -- For float to float conversions, we are done
10243 if Is_Floating_Point_Type (Xtyp)
10245 Is_Floating_Point_Type (Btyp)
10250 -- Otherwise rewrite the conversion as described above
10252 Conv := Relocate_Node (N);
10253 Rewrite (Subtype_Mark (Conv), New_Occurrence_Of (Btyp, Loc));
10254 Set_Etype (Conv, Btyp);
10256 -- Enable overflow except for case of integer to float conversions,
10257 -- where it is never required, since we can never have overflow in
10260 if not Is_Integer_Type (Etype (Operand)) then
10261 Enable_Overflow_Check (Conv);
10264 Tnn := Make_Temporary (Loc, 'T', Conv);
10266 Insert_Actions (N, New_List (
10267 Make_Object_Declaration (Loc,
10268 Defining_Identifier => Tnn,
10269 Object_Definition => New_Occurrence_Of (Btyp, Loc),
10270 Constant_Present => True,
10271 Expression => Conv),
10273 Make_Raise_Constraint_Error (Loc,
10278 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
10280 Make_Attribute_Reference (Loc,
10281 Attribute_Name => Name_First,
10283 New_Occurrence_Of (Target_Type, Loc))),
10287 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
10289 Make_Attribute_Reference (Loc,
10290 Attribute_Name => Name_Last,
10292 New_Occurrence_Of (Target_Type, Loc)))),
10293 Reason => CE_Range_Check_Failed)));
10295 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
10296 Analyze_And_Resolve (N, Btyp);
10297 end Real_Range_Check;
10299 -----------------------------
10300 -- Has_Extra_Accessibility --
10301 -----------------------------
10303 -- Returns true for a formal of an anonymous access type or for
10304 -- an Ada 2012-style stand-alone object of an anonymous access type.
10306 function Has_Extra_Accessibility (Id : Entity_Id) return Boolean is
10308 if Is_Formal (Id) or else Ekind_In (Id, E_Constant, E_Variable) then
10309 return Present (Effective_Extra_Accessibility (Id));
10313 end Has_Extra_Accessibility;
10315 -- Start of processing for Expand_N_Type_Conversion
10318 -- First remove check marks put by the semantic analysis on the type
10319 -- conversion between array types. We need these checks, and they will
10320 -- be generated by this expansion routine, but we do not depend on these
10321 -- flags being set, and since we do intend to expand the checks in the
10322 -- front end, we don't want them on the tree passed to the back end.
10324 if Is_Array_Type (Target_Type) then
10325 if Is_Constrained (Target_Type) then
10326 Set_Do_Length_Check (N, False);
10328 Set_Do_Range_Check (Operand, False);
10332 -- Nothing at all to do if conversion is to the identical type so remove
10333 -- the conversion completely, it is useless, except that it may carry
10334 -- an Assignment_OK attribute, which must be propagated to the operand.
10336 if Operand_Type = Target_Type then
10337 if Assignment_OK (N) then
10338 Set_Assignment_OK (Operand);
10341 Rewrite (N, Relocate_Node (Operand));
10345 -- Nothing to do if this is the second argument of read. This is a
10346 -- "backwards" conversion that will be handled by the specialized code
10347 -- in attribute processing.
10349 if Nkind (Parent (N)) = N_Attribute_Reference
10350 and then Attribute_Name (Parent (N)) = Name_Read
10351 and then Next (First (Expressions (Parent (N)))) = N
10356 -- Check for case of converting to a type that has an invariant
10357 -- associated with it. This required an invariant check. We convert
10363 -- do invariant_check (typ (expr)) in typ (expr);
10365 -- using Duplicate_Subexpr to avoid multiple side effects
10367 -- Note: the Comes_From_Source check, and then the resetting of this
10368 -- flag prevents what would otherwise be an infinite recursion.
10370 if Has_Invariants (Target_Type)
10371 and then Present (Invariant_Procedure (Target_Type))
10372 and then Comes_From_Source (N)
10374 Set_Comes_From_Source (N, False);
10376 Make_Expression_With_Actions (Loc,
10377 Actions => New_List (
10378 Make_Invariant_Call (Duplicate_Subexpr (N))),
10379 Expression => Duplicate_Subexpr_No_Checks (N)));
10380 Analyze_And_Resolve (N, Target_Type);
10384 -- Here if we may need to expand conversion
10386 -- If the operand of the type conversion is an arithmetic operation on
10387 -- signed integers, and the based type of the signed integer type in
10388 -- question is smaller than Standard.Integer, we promote both of the
10389 -- operands to type Integer.
10391 -- For example, if we have
10393 -- target-type (opnd1 + opnd2)
10395 -- and opnd1 and opnd2 are of type short integer, then we rewrite
10398 -- target-type (integer(opnd1) + integer(opnd2))
10400 -- We do this because we are always allowed to compute in a larger type
10401 -- if we do the right thing with the result, and in this case we are
10402 -- going to do a conversion which will do an appropriate check to make
10403 -- sure that things are in range of the target type in any case. This
10404 -- avoids some unnecessary intermediate overflows.
10406 -- We might consider a similar transformation in the case where the
10407 -- target is a real type or a 64-bit integer type, and the operand
10408 -- is an arithmetic operation using a 32-bit integer type. However,
10409 -- we do not bother with this case, because it could cause significant
10410 -- inefficiencies on 32-bit machines. On a 64-bit machine it would be
10411 -- much cheaper, but we don't want different behavior on 32-bit and
10412 -- 64-bit machines. Note that the exclusion of the 64-bit case also
10413 -- handles the configurable run-time cases where 64-bit arithmetic
10414 -- may simply be unavailable.
10416 -- Note: this circuit is partially redundant with respect to the circuit
10417 -- in Checks.Apply_Arithmetic_Overflow_Check, but we catch more cases in
10418 -- the processing here. Also we still need the Checks circuit, since we
10419 -- have to be sure not to generate junk overflow checks in the first
10420 -- place, since it would be trick to remove them here.
10422 if Integer_Promotion_Possible (N) then
10424 -- All conditions met, go ahead with transformation
10432 Make_Type_Conversion (Loc,
10433 Subtype_Mark => New_Occurrence_Of (Standard_Integer, Loc),
10434 Expression => Relocate_Node (Right_Opnd (Operand)));
10436 Opnd := New_Op_Node (Nkind (Operand), Loc);
10437 Set_Right_Opnd (Opnd, R);
10439 if Nkind (Operand) in N_Binary_Op then
10441 Make_Type_Conversion (Loc,
10442 Subtype_Mark => New_Occurrence_Of (Standard_Integer, Loc),
10443 Expression => Relocate_Node (Left_Opnd (Operand)));
10445 Set_Left_Opnd (Opnd, L);
10449 Make_Type_Conversion (Loc,
10450 Subtype_Mark => Relocate_Node (Subtype_Mark (N)),
10451 Expression => Opnd));
10453 Analyze_And_Resolve (N, Target_Type);
10458 -- Do validity check if validity checking operands
10460 if Validity_Checks_On and Validity_Check_Operands then
10461 Ensure_Valid (Operand);
10464 -- Special case of converting from non-standard boolean type
10466 if Is_Boolean_Type (Operand_Type)
10467 and then (Nonzero_Is_True (Operand_Type))
10469 Adjust_Condition (Operand);
10470 Set_Etype (Operand, Standard_Boolean);
10471 Operand_Type := Standard_Boolean;
10474 -- Case of converting to an access type
10476 if Is_Access_Type (Target_Type) then
10478 -- Apply an accessibility check when the conversion operand is an
10479 -- access parameter (or a renaming thereof), unless conversion was
10480 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
10481 -- Note that other checks may still need to be applied below (such
10482 -- as tagged type checks).
10484 if Is_Entity_Name (Operand)
10485 and then Has_Extra_Accessibility (Entity (Operand))
10486 and then Ekind (Etype (Operand)) = E_Anonymous_Access_Type
10487 and then (Nkind (Original_Node (N)) /= N_Attribute_Reference
10488 or else Attribute_Name (Original_Node (N)) = Name_Access)
10490 Apply_Accessibility_Check
10491 (Operand, Target_Type, Insert_Node => Operand);
10493 -- If the level of the operand type is statically deeper than the
10494 -- level of the target type, then force Program_Error. Note that this
10495 -- can only occur for cases where the attribute is within the body of
10496 -- an instantiation, otherwise the conversion will already have been
10497 -- rejected as illegal.
10499 -- Note: warnings are issued by the analyzer for the instance cases
10501 elsif In_Instance_Body
10503 -- The case where the target type is an anonymous access type of
10504 -- a discriminant is excluded, because the level of such a type
10505 -- depends on the context and currently the level returned for such
10506 -- types is zero, resulting in warnings about about check failures
10507 -- in certain legal cases involving class-wide interfaces as the
10508 -- designated type (some cases, such as return statements, are
10509 -- checked at run time, but not clear if these are handled right
10510 -- in general, see 3.10.2(12/2-12.5/3) ???).
10513 not (Ekind (Target_Type) = E_Anonymous_Access_Type
10514 and then Present (Associated_Node_For_Itype (Target_Type))
10515 and then Nkind (Associated_Node_For_Itype (Target_Type)) =
10516 N_Discriminant_Specification)
10518 Type_Access_Level (Operand_Type) > Type_Access_Level (Target_Type)
10520 Raise_Accessibility_Error;
10522 -- When the operand is a selected access discriminant the check needs
10523 -- to be made against the level of the object denoted by the prefix
10524 -- of the selected name. Force Program_Error for this case as well
10525 -- (this accessibility violation can only happen if within the body
10526 -- of an instantiation).
10528 elsif In_Instance_Body
10529 and then Ekind (Operand_Type) = E_Anonymous_Access_Type
10530 and then Nkind (Operand) = N_Selected_Component
10531 and then Object_Access_Level (Operand) >
10532 Type_Access_Level (Target_Type)
10534 Raise_Accessibility_Error;
10539 -- Case of conversions of tagged types and access to tagged types
10541 -- When needed, that is to say when the expression is class-wide, Add
10542 -- runtime a tag check for (strict) downward conversion by using the
10543 -- membership test, generating:
10545 -- [constraint_error when Operand not in Target_Type'Class]
10547 -- or in the access type case
10549 -- [constraint_error
10550 -- when Operand /= null
10551 -- and then Operand.all not in
10552 -- Designated_Type (Target_Type)'Class]
10554 if (Is_Access_Type (Target_Type)
10555 and then Is_Tagged_Type (Designated_Type (Target_Type)))
10556 or else Is_Tagged_Type (Target_Type)
10558 -- Do not do any expansion in the access type case if the parent is a
10559 -- renaming, since this is an error situation which will be caught by
10560 -- Sem_Ch8, and the expansion can interfere with this error check.
10562 if Is_Access_Type (Target_Type) and then Is_Renamed_Object (N) then
10566 -- Otherwise, proceed with processing tagged conversion
10568 Tagged_Conversion : declare
10569 Actual_Op_Typ : Entity_Id;
10570 Actual_Targ_Typ : Entity_Id;
10571 Make_Conversion : Boolean := False;
10572 Root_Op_Typ : Entity_Id;
10574 procedure Make_Tag_Check (Targ_Typ : Entity_Id);
10575 -- Create a membership check to test whether Operand is a member
10576 -- of Targ_Typ. If the original Target_Type is an access, include
10577 -- a test for null value. The check is inserted at N.
10579 --------------------
10580 -- Make_Tag_Check --
10581 --------------------
10583 procedure Make_Tag_Check (Targ_Typ : Entity_Id) is
10588 -- [Constraint_Error
10589 -- when Operand /= null
10590 -- and then Operand.all not in Targ_Typ]
10592 if Is_Access_Type (Target_Type) then
10594 Make_And_Then (Loc,
10597 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
10598 Right_Opnd => Make_Null (Loc)),
10603 Make_Explicit_Dereference (Loc,
10604 Prefix => Duplicate_Subexpr_No_Checks (Operand)),
10605 Right_Opnd => New_Occurrence_Of (Targ_Typ, Loc)));
10608 -- [Constraint_Error when Operand not in Targ_Typ]
10613 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
10614 Right_Opnd => New_Occurrence_Of (Targ_Typ, Loc));
10618 Make_Raise_Constraint_Error (Loc,
10620 Reason => CE_Tag_Check_Failed));
10621 end Make_Tag_Check;
10623 -- Start of processing for Tagged_Conversion
10626 -- Handle entities from the limited view
10628 if Is_Access_Type (Operand_Type) then
10630 Available_View (Designated_Type (Operand_Type));
10632 Actual_Op_Typ := Operand_Type;
10635 if Is_Access_Type (Target_Type) then
10637 Available_View (Designated_Type (Target_Type));
10639 Actual_Targ_Typ := Target_Type;
10642 Root_Op_Typ := Root_Type (Actual_Op_Typ);
10644 -- Ada 2005 (AI-251): Handle interface type conversion
10646 if Is_Interface (Actual_Op_Typ)
10648 Is_Interface (Actual_Targ_Typ)
10650 Expand_Interface_Conversion (N);
10654 if not Tag_Checks_Suppressed (Actual_Targ_Typ) then
10656 -- Create a runtime tag check for a downward class-wide type
10659 if Is_Class_Wide_Type (Actual_Op_Typ)
10660 and then Actual_Op_Typ /= Actual_Targ_Typ
10661 and then Root_Op_Typ /= Actual_Targ_Typ
10662 and then Is_Ancestor (Root_Op_Typ, Actual_Targ_Typ,
10663 Use_Full_View => True)
10665 Make_Tag_Check (Class_Wide_Type (Actual_Targ_Typ));
10666 Make_Conversion := True;
10669 -- AI05-0073: If the result subtype of the function is defined
10670 -- by an access_definition designating a specific tagged type
10671 -- T, a check is made that the result value is null or the tag
10672 -- of the object designated by the result value identifies T.
10673 -- Constraint_Error is raised if this check fails.
10675 if Nkind (Parent (N)) = N_Simple_Return_Statement then
10678 Func_Typ : Entity_Id;
10681 -- Climb scope stack looking for the enclosing function
10683 Func := Current_Scope;
10684 while Present (Func)
10685 and then Ekind (Func) /= E_Function
10687 Func := Scope (Func);
10690 -- The function's return subtype must be defined using
10691 -- an access definition.
10693 if Nkind (Result_Definition (Parent (Func))) =
10694 N_Access_Definition
10696 Func_Typ := Directly_Designated_Type (Etype (Func));
10698 -- The return subtype denotes a specific tagged type,
10699 -- in other words, a non class-wide type.
10701 if Is_Tagged_Type (Func_Typ)
10702 and then not Is_Class_Wide_Type (Func_Typ)
10704 Make_Tag_Check (Actual_Targ_Typ);
10705 Make_Conversion := True;
10711 -- We have generated a tag check for either a class-wide type
10712 -- conversion or for AI05-0073.
10714 if Make_Conversion then
10719 Make_Unchecked_Type_Conversion (Loc,
10720 Subtype_Mark => New_Occurrence_Of (Target_Type, Loc),
10721 Expression => Relocate_Node (Expression (N)));
10723 Analyze_And_Resolve (N, Target_Type);
10727 end Tagged_Conversion;
10729 -- Case of other access type conversions
10731 elsif Is_Access_Type (Target_Type) then
10732 Apply_Constraint_Check (Operand, Target_Type);
10734 -- Case of conversions from a fixed-point type
10736 -- These conversions require special expansion and processing, found in
10737 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
10738 -- since from a semantic point of view, these are simple integer
10739 -- conversions, which do not need further processing.
10741 elsif Is_Fixed_Point_Type (Operand_Type)
10742 and then not Conversion_OK (N)
10744 -- We should never see universal fixed at this case, since the
10745 -- expansion of the constituent divide or multiply should have
10746 -- eliminated the explicit mention of universal fixed.
10748 pragma Assert (Operand_Type /= Universal_Fixed);
10750 -- Check for special case of the conversion to universal real that
10751 -- occurs as a result of the use of a round attribute. In this case,
10752 -- the real type for the conversion is taken from the target type of
10753 -- the Round attribute and the result must be marked as rounded.
10755 if Target_Type = Universal_Real
10756 and then Nkind (Parent (N)) = N_Attribute_Reference
10757 and then Attribute_Name (Parent (N)) = Name_Round
10759 Set_Rounded_Result (N);
10760 Set_Etype (N, Etype (Parent (N)));
10763 -- Otherwise do correct fixed-conversion, but skip these if the
10764 -- Conversion_OK flag is set, because from a semantic point of view
10765 -- these are simple integer conversions needing no further processing
10766 -- (the backend will simply treat them as integers).
10768 if not Conversion_OK (N) then
10769 if Is_Fixed_Point_Type (Etype (N)) then
10770 Expand_Convert_Fixed_To_Fixed (N);
10773 elsif Is_Integer_Type (Etype (N)) then
10774 Expand_Convert_Fixed_To_Integer (N);
10777 pragma Assert (Is_Floating_Point_Type (Etype (N)));
10778 Expand_Convert_Fixed_To_Float (N);
10783 -- Case of conversions to a fixed-point type
10785 -- These conversions require special expansion and processing, found in
10786 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
10787 -- since from a semantic point of view, these are simple integer
10788 -- conversions, which do not need further processing.
10790 elsif Is_Fixed_Point_Type (Target_Type)
10791 and then not Conversion_OK (N)
10793 if Is_Integer_Type (Operand_Type) then
10794 Expand_Convert_Integer_To_Fixed (N);
10797 pragma Assert (Is_Floating_Point_Type (Operand_Type));
10798 Expand_Convert_Float_To_Fixed (N);
10802 -- Case of float-to-integer conversions
10804 -- We also handle float-to-fixed conversions with Conversion_OK set
10805 -- since semantically the fixed-point target is treated as though it
10806 -- were an integer in such cases.
10808 elsif Is_Floating_Point_Type (Operand_Type)
10810 (Is_Integer_Type (Target_Type)
10812 (Is_Fixed_Point_Type (Target_Type) and then Conversion_OK (N)))
10814 -- One more check here, gcc is still not able to do conversions of
10815 -- this type with proper overflow checking, and so gigi is doing an
10816 -- approximation of what is required by doing floating-point compares
10817 -- with the end-point. But that can lose precision in some cases, and
10818 -- give a wrong result. Converting the operand to Universal_Real is
10819 -- helpful, but still does not catch all cases with 64-bit integers
10820 -- on targets with only 64-bit floats.
10822 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
10823 -- Can this code be removed ???
10825 if Do_Range_Check (Operand) then
10827 Make_Type_Conversion (Loc,
10829 New_Occurrence_Of (Universal_Real, Loc),
10831 Relocate_Node (Operand)));
10833 Set_Etype (Operand, Universal_Real);
10834 Enable_Range_Check (Operand);
10835 Set_Do_Range_Check (Expression (Operand), False);
10838 -- Case of array conversions
10840 -- Expansion of array conversions, add required length/range checks but
10841 -- only do this if there is no change of representation. For handling of
10842 -- this case, see Handle_Changed_Representation.
10844 elsif Is_Array_Type (Target_Type) then
10845 if Is_Constrained (Target_Type) then
10846 Apply_Length_Check (Operand, Target_Type);
10848 Apply_Range_Check (Operand, Target_Type);
10851 Handle_Changed_Representation;
10853 -- Case of conversions of discriminated types
10855 -- Add required discriminant checks if target is constrained. Again this
10856 -- change is skipped if we have a change of representation.
10858 elsif Has_Discriminants (Target_Type)
10859 and then Is_Constrained (Target_Type)
10861 Apply_Discriminant_Check (Operand, Target_Type);
10862 Handle_Changed_Representation;
10864 -- Case of all other record conversions. The only processing required
10865 -- is to check for a change of representation requiring the special
10866 -- assignment processing.
10868 elsif Is_Record_Type (Target_Type) then
10870 -- Ada 2005 (AI-216): Program_Error is raised when converting from
10871 -- a derived Unchecked_Union type to an unconstrained type that is
10872 -- not Unchecked_Union if the operand lacks inferable discriminants.
10874 if Is_Derived_Type (Operand_Type)
10875 and then Is_Unchecked_Union (Base_Type (Operand_Type))
10876 and then not Is_Constrained (Target_Type)
10877 and then not Is_Unchecked_Union (Base_Type (Target_Type))
10878 and then not Has_Inferable_Discriminants (Operand)
10880 -- To prevent Gigi from generating illegal code, we generate a
10881 -- Program_Error node, but we give it the target type of the
10882 -- conversion (is this requirement documented somewhere ???)
10885 PE : constant Node_Id := Make_Raise_Program_Error (Loc,
10886 Reason => PE_Unchecked_Union_Restriction);
10889 Set_Etype (PE, Target_Type);
10894 Handle_Changed_Representation;
10897 -- Case of conversions of enumeration types
10899 elsif Is_Enumeration_Type (Target_Type) then
10901 -- Special processing is required if there is a change of
10902 -- representation (from enumeration representation clauses).
10904 if not Same_Representation (Target_Type, Operand_Type) then
10906 -- Convert: x(y) to x'val (ytyp'val (y))
10909 Make_Attribute_Reference (Loc,
10910 Prefix => New_Occurrence_Of (Target_Type, Loc),
10911 Attribute_Name => Name_Val,
10912 Expressions => New_List (
10913 Make_Attribute_Reference (Loc,
10914 Prefix => New_Occurrence_Of (Operand_Type, Loc),
10915 Attribute_Name => Name_Pos,
10916 Expressions => New_List (Operand)))));
10918 Analyze_And_Resolve (N, Target_Type);
10921 -- Case of conversions to floating-point
10923 elsif Is_Floating_Point_Type (Target_Type) then
10927 -- At this stage, either the conversion node has been transformed into
10928 -- some other equivalent expression, or left as a conversion that can be
10929 -- handled by Gigi, in the following cases:
10931 -- Conversions with no change of representation or type
10933 -- Numeric conversions involving integer, floating- and fixed-point
10934 -- values. Fixed-point values are allowed only if Conversion_OK is
10935 -- set, i.e. if the fixed-point values are to be treated as integers.
10937 -- No other conversions should be passed to Gigi
10939 -- Check: are these rules stated in sinfo??? if so, why restate here???
10941 -- The only remaining step is to generate a range check if we still have
10942 -- a type conversion at this stage and Do_Range_Check is set. For now we
10943 -- do this only for conversions of discrete types and for float-to-float
10946 if Nkind (N) = N_Type_Conversion then
10948 -- For now we only support floating-point cases where both source
10949 -- and target are floating-point types. Conversions where the source
10950 -- and target involve integer or fixed-point types are still TBD,
10951 -- though not clear whether those can even happen at this point, due
10952 -- to transformations above. ???
10954 if Is_Floating_Point_Type (Etype (N))
10955 and then Is_Floating_Point_Type (Etype (Expression (N)))
10957 if Do_Range_Check (Expression (N))
10958 and then Is_Floating_Point_Type (Target_Type)
10960 Generate_Range_Check
10961 (Expression (N), Target_Type, CE_Range_Check_Failed);
10964 -- Discrete-to-discrete conversions
10966 elsif Is_Discrete_Type (Etype (N)) then
10968 Expr : constant Node_Id := Expression (N);
10973 if Do_Range_Check (Expr)
10974 and then Is_Discrete_Type (Etype (Expr))
10976 Set_Do_Range_Check (Expr, False);
10978 -- Before we do a range check, we have to deal with treating
10979 -- a fixed-point operand as an integer. The way we do this
10980 -- is simply to do an unchecked conversion to an appropriate
10981 -- integer type large enough to hold the result.
10983 -- This code is not active yet, because we are only dealing
10984 -- with discrete types so far ???
10986 if Nkind (Expr) in N_Has_Treat_Fixed_As_Integer
10987 and then Treat_Fixed_As_Integer (Expr)
10989 Ftyp := Base_Type (Etype (Expr));
10991 if Esize (Ftyp) >= Esize (Standard_Integer) then
10992 Ityp := Standard_Long_Long_Integer;
10994 Ityp := Standard_Integer;
10997 Rewrite (Expr, Unchecked_Convert_To (Ityp, Expr));
11000 -- Reset overflow flag, since the range check will include
11001 -- dealing with possible overflow, and generate the check.
11002 -- If Address is either a source type or target type,
11003 -- suppress range check to avoid typing anomalies when
11004 -- it is a visible integer type.
11006 Set_Do_Overflow_Check (N, False);
11008 if not Is_Descendent_Of_Address (Etype (Expr))
11009 and then not Is_Descendent_Of_Address (Target_Type)
11011 Generate_Range_Check
11012 (Expr, Target_Type, CE_Range_Check_Failed);
11019 -- Here at end of processing
11022 -- Apply predicate check if required. Note that we can't just call
11023 -- Apply_Predicate_Check here, because the type looks right after
11024 -- the conversion and it would omit the check. The Comes_From_Source
11025 -- guard is necessary to prevent infinite recursions when we generate
11026 -- internal conversions for the purpose of checking predicates.
11028 if Present (Predicate_Function (Target_Type))
11029 and then Target_Type /= Operand_Type
11030 and then Comes_From_Source (N)
11033 New_Expr : constant Node_Id := Duplicate_Subexpr (N);
11036 -- Avoid infinite recursion on the subsequent expansion of
11037 -- of the copy of the original type conversion.
11039 Set_Comes_From_Source (New_Expr, False);
11040 Insert_Action (N, Make_Predicate_Check (Target_Type, New_Expr));
11043 end Expand_N_Type_Conversion;
11045 -----------------------------------
11046 -- Expand_N_Unchecked_Expression --
11047 -----------------------------------
11049 -- Remove the unchecked expression node from the tree. Its job was simply
11050 -- to make sure that its constituent expression was handled with checks
11051 -- off, and now that that is done, we can remove it from the tree, and
11052 -- indeed must, since Gigi does not expect to see these nodes.
11054 procedure Expand_N_Unchecked_Expression (N : Node_Id) is
11055 Exp : constant Node_Id := Expression (N);
11057 Set_Assignment_OK (Exp, Assignment_OK (N) or else Assignment_OK (Exp));
11059 end Expand_N_Unchecked_Expression;
11061 ----------------------------------------
11062 -- Expand_N_Unchecked_Type_Conversion --
11063 ----------------------------------------
11065 -- If this cannot be handled by Gigi and we haven't already made a
11066 -- temporary for it, do it now.
11068 procedure Expand_N_Unchecked_Type_Conversion (N : Node_Id) is
11069 Target_Type : constant Entity_Id := Etype (N);
11070 Operand : constant Node_Id := Expression (N);
11071 Operand_Type : constant Entity_Id := Etype (Operand);
11074 -- Nothing at all to do if conversion is to the identical type so remove
11075 -- the conversion completely, it is useless, except that it may carry
11076 -- an Assignment_OK indication which must be propagated to the operand.
11078 if Operand_Type = Target_Type then
11080 -- Code duplicates Expand_N_Unchecked_Expression above, factor???
11082 if Assignment_OK (N) then
11083 Set_Assignment_OK (Operand);
11086 Rewrite (N, Relocate_Node (Operand));
11090 -- If we have a conversion of a compile time known value to a target
11091 -- type and the value is in range of the target type, then we can simply
11092 -- replace the construct by an integer literal of the correct type. We
11093 -- only apply this to integer types being converted. Possibly it may
11094 -- apply in other cases, but it is too much trouble to worry about.
11096 -- Note that we do not do this transformation if the Kill_Range_Check
11097 -- flag is set, since then the value may be outside the expected range.
11098 -- This happens in the Normalize_Scalars case.
11100 -- We also skip this if either the target or operand type is biased
11101 -- because in this case, the unchecked conversion is supposed to
11102 -- preserve the bit pattern, not the integer value.
11104 if Is_Integer_Type (Target_Type)
11105 and then not Has_Biased_Representation (Target_Type)
11106 and then Is_Integer_Type (Operand_Type)
11107 and then not Has_Biased_Representation (Operand_Type)
11108 and then Compile_Time_Known_Value (Operand)
11109 and then not Kill_Range_Check (N)
11112 Val : constant Uint := Expr_Value (Operand);
11115 if Compile_Time_Known_Value (Type_Low_Bound (Target_Type))
11117 Compile_Time_Known_Value (Type_High_Bound (Target_Type))
11119 Val >= Expr_Value (Type_Low_Bound (Target_Type))
11121 Val <= Expr_Value (Type_High_Bound (Target_Type))
11123 Rewrite (N, Make_Integer_Literal (Sloc (N), Val));
11125 -- If Address is the target type, just set the type to avoid a
11126 -- spurious type error on the literal when Address is a visible
11129 if Is_Descendent_Of_Address (Target_Type) then
11130 Set_Etype (N, Target_Type);
11132 Analyze_And_Resolve (N, Target_Type);
11140 -- Nothing to do if conversion is safe
11142 if Safe_Unchecked_Type_Conversion (N) then
11146 -- Otherwise force evaluation unless Assignment_OK flag is set (this
11147 -- flag indicates ??? More comments needed here)
11149 if Assignment_OK (N) then
11152 Force_Evaluation (N);
11154 end Expand_N_Unchecked_Type_Conversion;
11156 ----------------------------
11157 -- Expand_Record_Equality --
11158 ----------------------------
11160 -- For non-variant records, Equality is expanded when needed into:
11162 -- and then Lhs.Discr1 = Rhs.Discr1
11164 -- and then Lhs.Discrn = Rhs.Discrn
11165 -- and then Lhs.Cmp1 = Rhs.Cmp1
11167 -- and then Lhs.Cmpn = Rhs.Cmpn
11169 -- The expression is folded by the back-end for adjacent fields. This
11170 -- function is called for tagged record in only one occasion: for imple-
11171 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
11172 -- otherwise the primitive "=" is used directly.
11174 function Expand_Record_Equality
11179 Bodies : List_Id) return Node_Id
11181 Loc : constant Source_Ptr := Sloc (Nod);
11186 First_Time : Boolean := True;
11188 function Element_To_Compare (C : Entity_Id) return Entity_Id;
11189 -- Return the next discriminant or component to compare, starting with
11190 -- C, skipping inherited components.
11192 ------------------------
11193 -- Element_To_Compare --
11194 ------------------------
11196 function Element_To_Compare (C : Entity_Id) return Entity_Id is
11202 -- Exit loop when the next element to be compared is found, or
11203 -- there is no more such element.
11205 exit when No (Comp);
11207 exit when Ekind_In (Comp, E_Discriminant, E_Component)
11210 -- Skip inherited components
11212 -- Note: for a tagged type, we always generate the "=" primitive
11213 -- for the base type (not on the first subtype), so the test for
11214 -- Comp /= Original_Record_Component (Comp) is True for
11215 -- inherited components only.
11217 (Is_Tagged_Type (Typ)
11218 and then Comp /= Original_Record_Component (Comp))
11222 or else Chars (Comp) = Name_uTag
11224 -- The .NET/JVM version of type Root_Controlled contains two
11225 -- fields which should not be considered part of the object. To
11226 -- achieve proper equiality between two controlled objects on
11227 -- .NET/JVM, skip _Parent whenever it has type Root_Controlled.
11229 or else (Chars (Comp) = Name_uParent
11230 and then VM_Target /= No_VM
11231 and then Etype (Comp) = RTE (RE_Root_Controlled))
11233 -- Skip interface elements (secondary tags???)
11235 or else Is_Interface (Etype (Comp)));
11237 Next_Entity (Comp);
11241 end Element_To_Compare;
11243 -- Start of processing for Expand_Record_Equality
11246 -- Generates the following code: (assuming that Typ has one Discr and
11247 -- component C2 is also a record)
11250 -- and then Lhs.Discr1 = Rhs.Discr1
11251 -- and then Lhs.C1 = Rhs.C1
11252 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
11254 -- and then Lhs.Cmpn = Rhs.Cmpn
11256 Result := New_Occurrence_Of (Standard_True, Loc);
11257 C := Element_To_Compare (First_Entity (Typ));
11258 while Present (C) loop
11266 First_Time := False;
11270 New_Lhs := New_Copy_Tree (Lhs);
11271 New_Rhs := New_Copy_Tree (Rhs);
11275 Expand_Composite_Equality (Nod, Etype (C),
11277 Make_Selected_Component (Loc,
11279 Selector_Name => New_Occurrence_Of (C, Loc)),
11281 Make_Selected_Component (Loc,
11283 Selector_Name => New_Occurrence_Of (C, Loc)),
11286 -- If some (sub)component is an unchecked_union, the whole
11287 -- operation will raise program error.
11289 if Nkind (Check) = N_Raise_Program_Error then
11291 Set_Etype (Result, Standard_Boolean);
11295 Make_And_Then (Loc,
11296 Left_Opnd => Result,
11297 Right_Opnd => Check);
11301 C := Element_To_Compare (Next_Entity (C));
11305 end Expand_Record_Equality;
11307 ---------------------------
11308 -- Expand_Set_Membership --
11309 ---------------------------
11311 procedure Expand_Set_Membership (N : Node_Id) is
11312 Lop : constant Node_Id := Left_Opnd (N);
11316 function Make_Cond (Alt : Node_Id) return Node_Id;
11317 -- If the alternative is a subtype mark, create a simple membership
11318 -- test. Otherwise create an equality test for it.
11324 function Make_Cond (Alt : Node_Id) return Node_Id is
11326 L : constant Node_Id := New_Copy (Lop);
11327 R : constant Node_Id := Relocate_Node (Alt);
11330 if (Is_Entity_Name (Alt) and then Is_Type (Entity (Alt)))
11331 or else Nkind (Alt) = N_Range
11334 Make_In (Sloc (Alt),
11339 Make_Op_Eq (Sloc (Alt),
11347 -- Start of processing for Expand_Set_Membership
11350 Remove_Side_Effects (Lop);
11352 Alt := Last (Alternatives (N));
11353 Res := Make_Cond (Alt);
11356 while Present (Alt) loop
11358 Make_Or_Else (Sloc (Alt),
11359 Left_Opnd => Make_Cond (Alt),
11360 Right_Opnd => Res);
11365 Analyze_And_Resolve (N, Standard_Boolean);
11366 end Expand_Set_Membership;
11368 -----------------------------------
11369 -- Expand_Short_Circuit_Operator --
11370 -----------------------------------
11372 -- Deal with special expansion if actions are present for the right operand
11373 -- and deal with optimizing case of arguments being True or False. We also
11374 -- deal with the special case of non-standard boolean values.
11376 procedure Expand_Short_Circuit_Operator (N : Node_Id) is
11377 Loc : constant Source_Ptr := Sloc (N);
11378 Typ : constant Entity_Id := Etype (N);
11379 Left : constant Node_Id := Left_Opnd (N);
11380 Right : constant Node_Id := Right_Opnd (N);
11381 LocR : constant Source_Ptr := Sloc (Right);
11384 Shortcut_Value : constant Boolean := Nkind (N) = N_Or_Else;
11385 Shortcut_Ent : constant Entity_Id := Boolean_Literals (Shortcut_Value);
11386 -- If Left = Shortcut_Value then Right need not be evaluated
11389 -- Deal with non-standard booleans
11391 if Is_Boolean_Type (Typ) then
11392 Adjust_Condition (Left);
11393 Adjust_Condition (Right);
11394 Set_Etype (N, Standard_Boolean);
11397 -- Check for cases where left argument is known to be True or False
11399 if Compile_Time_Known_Value (Left) then
11401 -- Mark SCO for left condition as compile time known
11403 if Generate_SCO and then Comes_From_Source (Left) then
11404 Set_SCO_Condition (Left, Expr_Value_E (Left) = Standard_True);
11407 -- Rewrite True AND THEN Right / False OR ELSE Right to Right.
11408 -- Any actions associated with Right will be executed unconditionally
11409 -- and can thus be inserted into the tree unconditionally.
11411 if Expr_Value_E (Left) /= Shortcut_Ent then
11412 if Present (Actions (N)) then
11413 Insert_Actions (N, Actions (N));
11416 Rewrite (N, Right);
11418 -- Rewrite False AND THEN Right / True OR ELSE Right to Left.
11419 -- In this case we can forget the actions associated with Right,
11420 -- since they will never be executed.
11423 Kill_Dead_Code (Right);
11424 Kill_Dead_Code (Actions (N));
11425 Rewrite (N, New_Occurrence_Of (Shortcut_Ent, Loc));
11428 Adjust_Result_Type (N, Typ);
11432 -- If Actions are present for the right operand, we have to do some
11433 -- special processing. We can't just let these actions filter back into
11434 -- code preceding the short circuit (which is what would have happened
11435 -- if we had not trapped them in the short-circuit form), since they
11436 -- must only be executed if the right operand of the short circuit is
11437 -- executed and not otherwise.
11439 if Present (Actions (N)) then
11440 Actlist := Actions (N);
11442 -- We now use an Expression_With_Actions node for the right operand
11443 -- of the short-circuit form. Note that this solves the traceability
11444 -- problems for coverage analysis.
11447 Make_Expression_With_Actions (LocR,
11448 Expression => Relocate_Node (Right),
11449 Actions => Actlist));
11450 Set_Actions (N, No_List);
11451 Analyze_And_Resolve (Right, Standard_Boolean);
11453 Adjust_Result_Type (N, Typ);
11457 -- No actions present, check for cases of right argument True/False
11459 if Compile_Time_Known_Value (Right) then
11461 -- Mark SCO for left condition as compile time known
11463 if Generate_SCO and then Comes_From_Source (Right) then
11464 Set_SCO_Condition (Right, Expr_Value_E (Right) = Standard_True);
11467 -- Change (Left and then True), (Left or else False) to Left.
11468 -- Note that we know there are no actions associated with the right
11469 -- operand, since we just checked for this case above.
11471 if Expr_Value_E (Right) /= Shortcut_Ent then
11474 -- Change (Left and then False), (Left or else True) to Right,
11475 -- making sure to preserve any side effects associated with the Left
11479 Remove_Side_Effects (Left);
11480 Rewrite (N, New_Occurrence_Of (Shortcut_Ent, Loc));
11484 Adjust_Result_Type (N, Typ);
11485 end Expand_Short_Circuit_Operator;
11487 -------------------------------------
11488 -- Fixup_Universal_Fixed_Operation --
11489 -------------------------------------
11491 procedure Fixup_Universal_Fixed_Operation (N : Node_Id) is
11492 Conv : constant Node_Id := Parent (N);
11495 -- We must have a type conversion immediately above us
11497 pragma Assert (Nkind (Conv) = N_Type_Conversion);
11499 -- Normally the type conversion gives our target type. The exception
11500 -- occurs in the case of the Round attribute, where the conversion
11501 -- will be to universal real, and our real type comes from the Round
11502 -- attribute (as well as an indication that we must round the result)
11504 if Nkind (Parent (Conv)) = N_Attribute_Reference
11505 and then Attribute_Name (Parent (Conv)) = Name_Round
11507 Set_Etype (N, Etype (Parent (Conv)));
11508 Set_Rounded_Result (N);
11510 -- Normal case where type comes from conversion above us
11513 Set_Etype (N, Etype (Conv));
11515 end Fixup_Universal_Fixed_Operation;
11517 ---------------------------------
11518 -- Has_Inferable_Discriminants --
11519 ---------------------------------
11521 function Has_Inferable_Discriminants (N : Node_Id) return Boolean is
11523 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean;
11524 -- Determines whether the left-most prefix of a selected component is a
11525 -- formal parameter in a subprogram. Assumes N is a selected component.
11527 --------------------------------
11528 -- Prefix_Is_Formal_Parameter --
11529 --------------------------------
11531 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean is
11532 Sel_Comp : Node_Id;
11535 -- Move to the left-most prefix by climbing up the tree
11538 while Present (Parent (Sel_Comp))
11539 and then Nkind (Parent (Sel_Comp)) = N_Selected_Component
11541 Sel_Comp := Parent (Sel_Comp);
11544 return Ekind (Entity (Prefix (Sel_Comp))) in Formal_Kind;
11545 end Prefix_Is_Formal_Parameter;
11547 -- Start of processing for Has_Inferable_Discriminants
11550 -- For selected components, the subtype of the selector must be a
11551 -- constrained Unchecked_Union. If the component is subject to a
11552 -- per-object constraint, then the enclosing object must have inferable
11555 if Nkind (N) = N_Selected_Component then
11556 if Has_Per_Object_Constraint (Entity (Selector_Name (N))) then
11558 -- A small hack. If we have a per-object constrained selected
11559 -- component of a formal parameter, return True since we do not
11560 -- know the actual parameter association yet.
11562 if Prefix_Is_Formal_Parameter (N) then
11565 -- Otherwise, check the enclosing object and the selector
11568 return Has_Inferable_Discriminants (Prefix (N))
11569 and then Has_Inferable_Discriminants (Selector_Name (N));
11572 -- The call to Has_Inferable_Discriminants will determine whether
11573 -- the selector has a constrained Unchecked_Union nominal type.
11576 return Has_Inferable_Discriminants (Selector_Name (N));
11579 -- A qualified expression has inferable discriminants if its subtype
11580 -- mark is a constrained Unchecked_Union subtype.
11582 elsif Nkind (N) = N_Qualified_Expression then
11583 return Is_Unchecked_Union (Etype (Subtype_Mark (N)))
11584 and then Is_Constrained (Etype (Subtype_Mark (N)));
11586 -- For all other names, it is sufficient to have a constrained
11587 -- Unchecked_Union nominal subtype.
11590 return Is_Unchecked_Union (Base_Type (Etype (N)))
11591 and then Is_Constrained (Etype (N));
11593 end Has_Inferable_Discriminants;
11595 -------------------------------
11596 -- Insert_Dereference_Action --
11597 -------------------------------
11599 procedure Insert_Dereference_Action (N : Node_Id) is
11601 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean;
11602 -- Return true if type of P is derived from Checked_Pool;
11604 -----------------------------
11605 -- Is_Checked_Storage_Pool --
11606 -----------------------------
11608 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean is
11617 while T /= Etype (T) loop
11618 if Is_RTE (T, RE_Checked_Pool) then
11626 end Is_Checked_Storage_Pool;
11630 Typ : constant Entity_Id := Etype (N);
11631 Desig : constant Entity_Id := Available_View (Designated_Type (Typ));
11632 Loc : constant Source_Ptr := Sloc (N);
11633 Pool : constant Entity_Id := Associated_Storage_Pool (Typ);
11634 Pnod : constant Node_Id := Parent (N);
11640 Size_Bits : Node_Id;
11643 -- Start of processing for Insert_Dereference_Action
11646 pragma Assert (Nkind (Pnod) = N_Explicit_Dereference);
11648 -- Do not re-expand a dereference which has already been processed by
11651 if Has_Dereference_Action (Pnod) then
11654 -- Do not perform this type of expansion for internally-generated
11657 elsif not Comes_From_Source (Original_Node (Pnod)) then
11660 -- A dereference action is only applicable to objects which have been
11661 -- allocated on a checked pool.
11663 elsif not Is_Checked_Storage_Pool (Pool) then
11667 -- Extract the address of the dereferenced object. Generate:
11669 -- Addr : System.Address := <N>'Pool_Address;
11671 Addr := Make_Temporary (Loc, 'P');
11674 Make_Object_Declaration (Loc,
11675 Defining_Identifier => Addr,
11676 Object_Definition =>
11677 New_Occurrence_Of (RTE (RE_Address), Loc),
11679 Make_Attribute_Reference (Loc,
11680 Prefix => Duplicate_Subexpr_Move_Checks (N),
11681 Attribute_Name => Name_Pool_Address)));
11683 -- Calculate the size of the dereferenced object. Generate:
11685 -- Size : Storage_Count := <N>.all'Size / Storage_Unit;
11688 Make_Explicit_Dereference (Loc,
11689 Prefix => Duplicate_Subexpr_Move_Checks (N));
11690 Set_Has_Dereference_Action (Deref);
11693 Make_Attribute_Reference (Loc,
11695 Attribute_Name => Name_Size);
11697 -- Special case of an unconstrained array: need to add descriptor size
11699 if Is_Array_Type (Desig)
11700 and then not Is_Constrained (First_Subtype (Desig))
11705 Make_Attribute_Reference (Loc,
11707 New_Occurrence_Of (First_Subtype (Desig), Loc),
11708 Attribute_Name => Name_Descriptor_Size),
11709 Right_Opnd => Size_Bits);
11712 Size := Make_Temporary (Loc, 'S');
11714 Make_Object_Declaration (Loc,
11715 Defining_Identifier => Size,
11716 Object_Definition =>
11717 New_Occurrence_Of (RTE (RE_Storage_Count), Loc),
11719 Make_Op_Divide (Loc,
11720 Left_Opnd => Size_Bits,
11721 Right_Opnd => Make_Integer_Literal (Loc, System_Storage_Unit))));
11723 -- Calculate the alignment of the dereferenced object. Generate:
11724 -- Alig : constant Storage_Count := <N>.all'Alignment;
11727 Make_Explicit_Dereference (Loc,
11728 Prefix => Duplicate_Subexpr_Move_Checks (N));
11729 Set_Has_Dereference_Action (Deref);
11731 Alig := Make_Temporary (Loc, 'A');
11733 Make_Object_Declaration (Loc,
11734 Defining_Identifier => Alig,
11735 Object_Definition =>
11736 New_Occurrence_Of (RTE (RE_Storage_Count), Loc),
11738 Make_Attribute_Reference (Loc,
11740 Attribute_Name => Name_Alignment)));
11742 -- A dereference of a controlled object requires special processing. The
11743 -- finalization machinery requests additional space from the underlying
11744 -- pool to allocate and hide two pointers. As a result, a checked pool
11745 -- may mark the wrong memory as valid. Since checked pools do not have
11746 -- knowledge of hidden pointers, we have to bring the two pointers back
11747 -- in view in order to restore the original state of the object.
11749 if Needs_Finalization (Desig) then
11751 -- Adjust the address and size of the dereferenced object. Generate:
11752 -- Adjust_Controlled_Dereference (Addr, Size, Alig);
11755 Make_Procedure_Call_Statement (Loc,
11757 New_Occurrence_Of (RTE (RE_Adjust_Controlled_Dereference), Loc),
11758 Parameter_Associations => New_List (
11759 New_Occurrence_Of (Addr, Loc),
11760 New_Occurrence_Of (Size, Loc),
11761 New_Occurrence_Of (Alig, Loc)));
11763 -- Class-wide types complicate things because we cannot determine
11764 -- statically whether the actual object is truly controlled. We must
11765 -- generate a runtime check to detect this property. Generate:
11767 -- if Needs_Finalization (<N>.all'Tag) then
11771 if Is_Class_Wide_Type (Desig) then
11773 Make_Explicit_Dereference (Loc,
11774 Prefix => Duplicate_Subexpr_Move_Checks (N));
11775 Set_Has_Dereference_Action (Deref);
11778 Make_Implicit_If_Statement (N,
11780 Make_Function_Call (Loc,
11782 New_Occurrence_Of (RTE (RE_Needs_Finalization), Loc),
11783 Parameter_Associations => New_List (
11784 Make_Attribute_Reference (Loc,
11786 Attribute_Name => Name_Tag))),
11787 Then_Statements => New_List (Stmt));
11790 Insert_Action (N, Stmt);
11794 -- Dereference (Pool, Addr, Size, Alig);
11797 Make_Procedure_Call_Statement (Loc,
11800 (Find_Prim_Op (Etype (Pool), Name_Dereference), Loc),
11801 Parameter_Associations => New_List (
11802 New_Occurrence_Of (Pool, Loc),
11803 New_Occurrence_Of (Addr, Loc),
11804 New_Occurrence_Of (Size, Loc),
11805 New_Occurrence_Of (Alig, Loc))));
11807 -- Mark the explicit dereference as processed to avoid potential
11808 -- infinite expansion.
11810 Set_Has_Dereference_Action (Pnod);
11813 when RE_Not_Available =>
11815 end Insert_Dereference_Action;
11817 --------------------------------
11818 -- Integer_Promotion_Possible --
11819 --------------------------------
11821 function Integer_Promotion_Possible (N : Node_Id) return Boolean is
11822 Operand : constant Node_Id := Expression (N);
11823 Operand_Type : constant Entity_Id := Etype (Operand);
11824 Root_Operand_Type : constant Entity_Id := Root_Type (Operand_Type);
11827 pragma Assert (Nkind (N) = N_Type_Conversion);
11831 -- We only do the transformation for source constructs. We assume
11832 -- that the expander knows what it is doing when it generates code.
11834 Comes_From_Source (N)
11836 -- If the operand type is Short_Integer or Short_Short_Integer,
11837 -- then we will promote to Integer, which is available on all
11838 -- targets, and is sufficient to ensure no intermediate overflow.
11839 -- Furthermore it is likely to be as efficient or more efficient
11840 -- than using the smaller type for the computation so we do this
11841 -- unconditionally.
11844 (Root_Operand_Type = Base_Type (Standard_Short_Integer)
11846 Root_Operand_Type = Base_Type (Standard_Short_Short_Integer))
11848 -- Test for interesting operation, which includes addition,
11849 -- division, exponentiation, multiplication, subtraction, absolute
11850 -- value and unary negation. Unary "+" is omitted since it is a
11851 -- no-op and thus can't overflow.
11853 and then Nkind_In (Operand, N_Op_Abs,
11860 end Integer_Promotion_Possible;
11862 ------------------------------
11863 -- Make_Array_Comparison_Op --
11864 ------------------------------
11866 -- This is a hand-coded expansion of the following generic function:
11869 -- type elem is (<>);
11870 -- type index is (<>);
11871 -- type a is array (index range <>) of elem;
11873 -- function Gnnn (X : a; Y: a) return boolean is
11874 -- J : index := Y'first;
11877 -- if X'length = 0 then
11880 -- elsif Y'length = 0 then
11884 -- for I in X'range loop
11885 -- if X (I) = Y (J) then
11886 -- if J = Y'last then
11889 -- J := index'succ (J);
11893 -- return X (I) > Y (J);
11897 -- return X'length > Y'length;
11901 -- Note that since we are essentially doing this expansion by hand, we
11902 -- do not need to generate an actual or formal generic part, just the
11903 -- instantiated function itself.
11905 -- Perhaps we could have the actual generic available in the run-time,
11906 -- obtained by rtsfind, and actually expand a real instantiation ???
11908 function Make_Array_Comparison_Op
11910 Nod : Node_Id) return Node_Id
11912 Loc : constant Source_Ptr := Sloc (Nod);
11914 X : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uX);
11915 Y : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uY);
11916 I : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uI);
11917 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
11919 Index : constant Entity_Id := Base_Type (Etype (First_Index (Typ)));
11921 Loop_Statement : Node_Id;
11922 Loop_Body : Node_Id;
11924 Inner_If : Node_Id;
11925 Final_Expr : Node_Id;
11926 Func_Body : Node_Id;
11927 Func_Name : Entity_Id;
11933 -- if J = Y'last then
11936 -- J := index'succ (J);
11940 Make_Implicit_If_Statement (Nod,
11943 Left_Opnd => New_Occurrence_Of (J, Loc),
11945 Make_Attribute_Reference (Loc,
11946 Prefix => New_Occurrence_Of (Y, Loc),
11947 Attribute_Name => Name_Last)),
11949 Then_Statements => New_List (
11950 Make_Exit_Statement (Loc)),
11954 Make_Assignment_Statement (Loc,
11955 Name => New_Occurrence_Of (J, Loc),
11957 Make_Attribute_Reference (Loc,
11958 Prefix => New_Occurrence_Of (Index, Loc),
11959 Attribute_Name => Name_Succ,
11960 Expressions => New_List (New_Occurrence_Of (J, Loc))))));
11962 -- if X (I) = Y (J) then
11965 -- return X (I) > Y (J);
11969 Make_Implicit_If_Statement (Nod,
11973 Make_Indexed_Component (Loc,
11974 Prefix => New_Occurrence_Of (X, Loc),
11975 Expressions => New_List (New_Occurrence_Of (I, Loc))),
11978 Make_Indexed_Component (Loc,
11979 Prefix => New_Occurrence_Of (Y, Loc),
11980 Expressions => New_List (New_Occurrence_Of (J, Loc)))),
11982 Then_Statements => New_List (Inner_If),
11984 Else_Statements => New_List (
11985 Make_Simple_Return_Statement (Loc,
11989 Make_Indexed_Component (Loc,
11990 Prefix => New_Occurrence_Of (X, Loc),
11991 Expressions => New_List (New_Occurrence_Of (I, Loc))),
11994 Make_Indexed_Component (Loc,
11995 Prefix => New_Occurrence_Of (Y, Loc),
11996 Expressions => New_List (
11997 New_Occurrence_Of (J, Loc)))))));
11999 -- for I in X'range loop
12004 Make_Implicit_Loop_Statement (Nod,
12005 Identifier => Empty,
12007 Iteration_Scheme =>
12008 Make_Iteration_Scheme (Loc,
12009 Loop_Parameter_Specification =>
12010 Make_Loop_Parameter_Specification (Loc,
12011 Defining_Identifier => I,
12012 Discrete_Subtype_Definition =>
12013 Make_Attribute_Reference (Loc,
12014 Prefix => New_Occurrence_Of (X, Loc),
12015 Attribute_Name => Name_Range))),
12017 Statements => New_List (Loop_Body));
12019 -- if X'length = 0 then
12021 -- elsif Y'length = 0 then
12024 -- for ... loop ... end loop;
12025 -- return X'length > Y'length;
12029 Make_Attribute_Reference (Loc,
12030 Prefix => New_Occurrence_Of (X, Loc),
12031 Attribute_Name => Name_Length);
12034 Make_Attribute_Reference (Loc,
12035 Prefix => New_Occurrence_Of (Y, Loc),
12036 Attribute_Name => Name_Length);
12040 Left_Opnd => Length1,
12041 Right_Opnd => Length2);
12044 Make_Implicit_If_Statement (Nod,
12048 Make_Attribute_Reference (Loc,
12049 Prefix => New_Occurrence_Of (X, Loc),
12050 Attribute_Name => Name_Length),
12052 Make_Integer_Literal (Loc, 0)),
12056 Make_Simple_Return_Statement (Loc,
12057 Expression => New_Occurrence_Of (Standard_False, Loc))),
12059 Elsif_Parts => New_List (
12060 Make_Elsif_Part (Loc,
12064 Make_Attribute_Reference (Loc,
12065 Prefix => New_Occurrence_Of (Y, Loc),
12066 Attribute_Name => Name_Length),
12068 Make_Integer_Literal (Loc, 0)),
12072 Make_Simple_Return_Statement (Loc,
12073 Expression => New_Occurrence_Of (Standard_True, Loc))))),
12075 Else_Statements => New_List (
12077 Make_Simple_Return_Statement (Loc,
12078 Expression => Final_Expr)));
12082 Formals := New_List (
12083 Make_Parameter_Specification (Loc,
12084 Defining_Identifier => X,
12085 Parameter_Type => New_Occurrence_Of (Typ, Loc)),
12087 Make_Parameter_Specification (Loc,
12088 Defining_Identifier => Y,
12089 Parameter_Type => New_Occurrence_Of (Typ, Loc)));
12091 -- function Gnnn (...) return boolean is
12092 -- J : index := Y'first;
12097 Func_Name := Make_Temporary (Loc, 'G');
12100 Make_Subprogram_Body (Loc,
12102 Make_Function_Specification (Loc,
12103 Defining_Unit_Name => Func_Name,
12104 Parameter_Specifications => Formals,
12105 Result_Definition => New_Occurrence_Of (Standard_Boolean, Loc)),
12107 Declarations => New_List (
12108 Make_Object_Declaration (Loc,
12109 Defining_Identifier => J,
12110 Object_Definition => New_Occurrence_Of (Index, Loc),
12112 Make_Attribute_Reference (Loc,
12113 Prefix => New_Occurrence_Of (Y, Loc),
12114 Attribute_Name => Name_First))),
12116 Handled_Statement_Sequence =>
12117 Make_Handled_Sequence_Of_Statements (Loc,
12118 Statements => New_List (If_Stat)));
12121 end Make_Array_Comparison_Op;
12123 ---------------------------
12124 -- Make_Boolean_Array_Op --
12125 ---------------------------
12127 -- For logical operations on boolean arrays, expand in line the following,
12128 -- replacing 'and' with 'or' or 'xor' where needed:
12130 -- function Annn (A : typ; B: typ) return typ is
12133 -- for J in A'range loop
12134 -- C (J) := A (J) op B (J);
12139 -- Here typ is the boolean array type
12141 function Make_Boolean_Array_Op
12143 N : Node_Id) return Node_Id
12145 Loc : constant Source_Ptr := Sloc (N);
12147 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
12148 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
12149 C : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uC);
12150 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
12158 Func_Name : Entity_Id;
12159 Func_Body : Node_Id;
12160 Loop_Statement : Node_Id;
12164 Make_Indexed_Component (Loc,
12165 Prefix => New_Occurrence_Of (A, Loc),
12166 Expressions => New_List (New_Occurrence_Of (J, Loc)));
12169 Make_Indexed_Component (Loc,
12170 Prefix => New_Occurrence_Of (B, Loc),
12171 Expressions => New_List (New_Occurrence_Of (J, Loc)));
12174 Make_Indexed_Component (Loc,
12175 Prefix => New_Occurrence_Of (C, Loc),
12176 Expressions => New_List (New_Occurrence_Of (J, Loc)));
12178 if Nkind (N) = N_Op_And then
12182 Right_Opnd => B_J);
12184 elsif Nkind (N) = N_Op_Or then
12188 Right_Opnd => B_J);
12194 Right_Opnd => B_J);
12198 Make_Implicit_Loop_Statement (N,
12199 Identifier => Empty,
12201 Iteration_Scheme =>
12202 Make_Iteration_Scheme (Loc,
12203 Loop_Parameter_Specification =>
12204 Make_Loop_Parameter_Specification (Loc,
12205 Defining_Identifier => J,
12206 Discrete_Subtype_Definition =>
12207 Make_Attribute_Reference (Loc,
12208 Prefix => New_Occurrence_Of (A, Loc),
12209 Attribute_Name => Name_Range))),
12211 Statements => New_List (
12212 Make_Assignment_Statement (Loc,
12214 Expression => Op)));
12216 Formals := New_List (
12217 Make_Parameter_Specification (Loc,
12218 Defining_Identifier => A,
12219 Parameter_Type => New_Occurrence_Of (Typ, Loc)),
12221 Make_Parameter_Specification (Loc,
12222 Defining_Identifier => B,
12223 Parameter_Type => New_Occurrence_Of (Typ, Loc)));
12225 Func_Name := Make_Temporary (Loc, 'A');
12226 Set_Is_Inlined (Func_Name);
12229 Make_Subprogram_Body (Loc,
12231 Make_Function_Specification (Loc,
12232 Defining_Unit_Name => Func_Name,
12233 Parameter_Specifications => Formals,
12234 Result_Definition => New_Occurrence_Of (Typ, Loc)),
12236 Declarations => New_List (
12237 Make_Object_Declaration (Loc,
12238 Defining_Identifier => C,
12239 Object_Definition => New_Occurrence_Of (Typ, Loc))),
12241 Handled_Statement_Sequence =>
12242 Make_Handled_Sequence_Of_Statements (Loc,
12243 Statements => New_List (
12245 Make_Simple_Return_Statement (Loc,
12246 Expression => New_Occurrence_Of (C, Loc)))));
12249 end Make_Boolean_Array_Op;
12251 -----------------------------------------
12252 -- Minimized_Eliminated_Overflow_Check --
12253 -----------------------------------------
12255 function Minimized_Eliminated_Overflow_Check (N : Node_Id) return Boolean is
12258 Is_Signed_Integer_Type (Etype (N))
12259 and then Overflow_Check_Mode in Minimized_Or_Eliminated;
12260 end Minimized_Eliminated_Overflow_Check;
12262 --------------------------------
12263 -- Optimize_Length_Comparison --
12264 --------------------------------
12266 procedure Optimize_Length_Comparison (N : Node_Id) is
12267 Loc : constant Source_Ptr := Sloc (N);
12268 Typ : constant Entity_Id := Etype (N);
12273 -- First and Last attribute reference nodes, which end up as left and
12274 -- right operands of the optimized result.
12277 -- True for comparison operand of zero
12280 -- Comparison operand, set only if Is_Zero is false
12283 -- Entity whose length is being compared
12286 -- Integer_Literal node for length attribute expression, or Empty
12287 -- if there is no such expression present.
12290 -- Type of array index to which 'Length is applied
12292 Op : Node_Kind := Nkind (N);
12293 -- Kind of comparison operator, gets flipped if operands backwards
12295 function Is_Optimizable (N : Node_Id) return Boolean;
12296 -- Tests N to see if it is an optimizable comparison value (defined as
12297 -- constant zero or one, or something else where the value is known to
12298 -- be positive and in the range of 32-bits, and where the corresponding
12299 -- Length value is also known to be 32-bits. If result is true, sets
12300 -- Is_Zero, Ityp, and Comp accordingly.
12302 function Is_Entity_Length (N : Node_Id) return Boolean;
12303 -- Tests if N is a length attribute applied to a simple entity. If so,
12304 -- returns True, and sets Ent to the entity, and Index to the integer
12305 -- literal provided as an attribute expression, or to Empty if none.
12306 -- Also returns True if the expression is a generated type conversion
12307 -- whose expression is of the desired form. This latter case arises
12308 -- when Apply_Universal_Integer_Attribute_Check installs a conversion
12309 -- to check for being in range, which is not needed in this context.
12310 -- Returns False if neither condition holds.
12312 function Prepare_64 (N : Node_Id) return Node_Id;
12313 -- Given a discrete expression, returns a Long_Long_Integer typed
12314 -- expression representing the underlying value of the expression.
12315 -- This is done with an unchecked conversion to the result type. We
12316 -- use unchecked conversion to handle the enumeration type case.
12318 ----------------------
12319 -- Is_Entity_Length --
12320 ----------------------
12322 function Is_Entity_Length (N : Node_Id) return Boolean is
12324 if Nkind (N) = N_Attribute_Reference
12325 and then Attribute_Name (N) = Name_Length
12326 and then Is_Entity_Name (Prefix (N))
12328 Ent := Entity (Prefix (N));
12330 if Present (Expressions (N)) then
12331 Index := First (Expressions (N));
12338 elsif Nkind (N) = N_Type_Conversion
12339 and then not Comes_From_Source (N)
12341 return Is_Entity_Length (Expression (N));
12346 end Is_Entity_Length;
12348 --------------------
12349 -- Is_Optimizable --
12350 --------------------
12352 function Is_Optimizable (N : Node_Id) return Boolean is
12360 if Compile_Time_Known_Value (N) then
12361 Val := Expr_Value (N);
12363 if Val = Uint_0 then
12368 elsif Val = Uint_1 then
12375 -- Here we have to make sure of being within 32-bits
12377 Determine_Range (N, OK, Lo, Hi, Assume_Valid => True);
12380 or else Lo < Uint_1
12381 or else Hi > UI_From_Int (Int'Last)
12386 -- Comparison value was within range, so now we must check the index
12387 -- value to make sure it is also within 32-bits.
12389 Indx := First_Index (Etype (Ent));
12391 if Present (Index) then
12392 for J in 2 .. UI_To_Int (Intval (Index)) loop
12397 Ityp := Etype (Indx);
12399 if Esize (Ityp) > 32 then
12406 end Is_Optimizable;
12412 function Prepare_64 (N : Node_Id) return Node_Id is
12414 return Unchecked_Convert_To (Standard_Long_Long_Integer, N);
12417 -- Start of processing for Optimize_Length_Comparison
12420 -- Nothing to do if not a comparison
12422 if Op not in N_Op_Compare then
12426 -- Nothing to do if special -gnatd.P debug flag set
12428 if Debug_Flag_Dot_PP then
12432 -- Ent'Length op 0/1
12434 if Is_Entity_Length (Left_Opnd (N))
12435 and then Is_Optimizable (Right_Opnd (N))
12439 -- 0/1 op Ent'Length
12441 elsif Is_Entity_Length (Right_Opnd (N))
12442 and then Is_Optimizable (Left_Opnd (N))
12444 -- Flip comparison to opposite sense
12447 when N_Op_Lt => Op := N_Op_Gt;
12448 when N_Op_Le => Op := N_Op_Ge;
12449 when N_Op_Gt => Op := N_Op_Lt;
12450 when N_Op_Ge => Op := N_Op_Le;
12451 when others => null;
12454 -- Else optimization not possible
12460 -- Fall through if we will do the optimization
12462 -- Cases to handle:
12464 -- X'Length = 0 => X'First > X'Last
12465 -- X'Length = 1 => X'First = X'Last
12466 -- X'Length = n => X'First + (n - 1) = X'Last
12468 -- X'Length /= 0 => X'First <= X'Last
12469 -- X'Length /= 1 => X'First /= X'Last
12470 -- X'Length /= n => X'First + (n - 1) /= X'Last
12472 -- X'Length >= 0 => always true, warn
12473 -- X'Length >= 1 => X'First <= X'Last
12474 -- X'Length >= n => X'First + (n - 1) <= X'Last
12476 -- X'Length > 0 => X'First <= X'Last
12477 -- X'Length > 1 => X'First < X'Last
12478 -- X'Length > n => X'First + (n - 1) < X'Last
12480 -- X'Length <= 0 => X'First > X'Last (warn, could be =)
12481 -- X'Length <= 1 => X'First >= X'Last
12482 -- X'Length <= n => X'First + (n - 1) >= X'Last
12484 -- X'Length < 0 => always false (warn)
12485 -- X'Length < 1 => X'First > X'Last
12486 -- X'Length < n => X'First + (n - 1) > X'Last
12488 -- Note: for the cases of n (not constant 0,1), we require that the
12489 -- corresponding index type be integer or shorter (i.e. not 64-bit),
12490 -- and the same for the comparison value. Then we do the comparison
12491 -- using 64-bit arithmetic (actually long long integer), so that we
12492 -- cannot have overflow intefering with the result.
12494 -- First deal with warning cases
12503 Convert_To (Typ, New_Occurrence_Of (Standard_True, Loc)));
12504 Analyze_And_Resolve (N, Typ);
12505 Warn_On_Known_Condition (N);
12512 Convert_To (Typ, New_Occurrence_Of (Standard_False, Loc)));
12513 Analyze_And_Resolve (N, Typ);
12514 Warn_On_Known_Condition (N);
12518 if Constant_Condition_Warnings
12519 and then Comes_From_Source (Original_Node (N))
12521 Error_Msg_N ("could replace by ""'=""?c?", N);
12531 -- Build the First reference we will use
12534 Make_Attribute_Reference (Loc,
12535 Prefix => New_Occurrence_Of (Ent, Loc),
12536 Attribute_Name => Name_First);
12538 if Present (Index) then
12539 Set_Expressions (Left, New_List (New_Copy (Index)));
12542 -- If general value case, then do the addition of (n - 1), and
12543 -- also add the needed conversions to type Long_Long_Integer.
12545 if Present (Comp) then
12548 Left_Opnd => Prepare_64 (Left),
12550 Make_Op_Subtract (Loc,
12551 Left_Opnd => Prepare_64 (Comp),
12552 Right_Opnd => Make_Integer_Literal (Loc, 1)));
12555 -- Build the Last reference we will use
12558 Make_Attribute_Reference (Loc,
12559 Prefix => New_Occurrence_Of (Ent, Loc),
12560 Attribute_Name => Name_Last);
12562 if Present (Index) then
12563 Set_Expressions (Right, New_List (New_Copy (Index)));
12566 -- If general operand, convert Last reference to Long_Long_Integer
12568 if Present (Comp) then
12569 Right := Prepare_64 (Right);
12572 -- Check for cases to optimize
12574 -- X'Length = 0 => X'First > X'Last
12575 -- X'Length < 1 => X'First > X'Last
12576 -- X'Length < n => X'First + (n - 1) > X'Last
12578 if (Is_Zero and then Op = N_Op_Eq)
12579 or else (not Is_Zero and then Op = N_Op_Lt)
12584 Right_Opnd => Right);
12586 -- X'Length = 1 => X'First = X'Last
12587 -- X'Length = n => X'First + (n - 1) = X'Last
12589 elsif not Is_Zero and then Op = N_Op_Eq then
12593 Right_Opnd => Right);
12595 -- X'Length /= 0 => X'First <= X'Last
12596 -- X'Length > 0 => X'First <= X'Last
12598 elsif Is_Zero and (Op = N_Op_Ne or else Op = N_Op_Gt) then
12602 Right_Opnd => Right);
12604 -- X'Length /= 1 => X'First /= X'Last
12605 -- X'Length /= n => X'First + (n - 1) /= X'Last
12607 elsif not Is_Zero and then Op = N_Op_Ne then
12611 Right_Opnd => Right);
12613 -- X'Length >= 1 => X'First <= X'Last
12614 -- X'Length >= n => X'First + (n - 1) <= X'Last
12616 elsif not Is_Zero and then Op = N_Op_Ge then
12620 Right_Opnd => Right);
12622 -- X'Length > 1 => X'First < X'Last
12623 -- X'Length > n => X'First + (n = 1) < X'Last
12625 elsif not Is_Zero and then Op = N_Op_Gt then
12629 Right_Opnd => Right);
12631 -- X'Length <= 1 => X'First >= X'Last
12632 -- X'Length <= n => X'First + (n - 1) >= X'Last
12634 elsif not Is_Zero and then Op = N_Op_Le then
12638 Right_Opnd => Right);
12640 -- Should not happen at this stage
12643 raise Program_Error;
12646 -- Rewrite and finish up
12648 Rewrite (N, Result);
12649 Analyze_And_Resolve (N, Typ);
12651 end Optimize_Length_Comparison;
12653 ------------------------------
12654 -- Process_Transient_Object --
12655 ------------------------------
12657 procedure Process_Transient_Object
12659 Rel_Node : Node_Id)
12661 Loc : constant Source_Ptr := Sloc (Decl);
12662 Obj_Id : constant Entity_Id := Defining_Identifier (Decl);
12663 Obj_Typ : constant Node_Id := Etype (Obj_Id);
12664 Desig_Typ : Entity_Id;
12666 Fin_Stmts : List_Id;
12667 Ptr_Id : Entity_Id;
12668 Temp_Id : Entity_Id;
12669 Temp_Ins : Node_Id;
12671 Hook_Context : constant Node_Id := Find_Hook_Context (Rel_Node);
12672 -- Node on which to insert the hook pointer (as an action): the
12673 -- innermost enclosing non-transient scope.
12675 Finalization_Context : Node_Id;
12676 -- Node after which to insert finalization actions
12678 Finalize_Always : Boolean;
12679 -- If False, call to finalizer includes a test of whether the hook
12680 -- pointer is null.
12683 -- Step 0: determine where to attach finalization actions in the tree
12685 -- Special case for Boolean EWAs: capture expression in a temporary,
12686 -- whose declaration will serve as the context around which to insert
12687 -- finalization code. The finalization thus remains local to the
12688 -- specific condition being evaluated.
12690 if Is_Boolean_Type (Etype (Rel_Node)) then
12692 -- In this case, the finalization context is chosen so that we know
12693 -- at finalization point that the hook pointer is never null, so no
12694 -- need for a test, we can call the finalizer unconditionally, except
12695 -- in the case where the object is created in a specific branch of a
12696 -- conditional expression.
12699 not Within_Case_Or_If_Expression (Rel_Node)
12700 and then not Nkind_In
12701 (Original_Node (Rel_Node), N_Case_Expression,
12705 Loc : constant Source_Ptr := Sloc (Rel_Node);
12706 Temp : constant Entity_Id := Make_Temporary (Loc, 'E', Rel_Node);
12709 Append_To (Actions (Rel_Node),
12710 Make_Object_Declaration (Loc,
12711 Defining_Identifier => Temp,
12712 Constant_Present => True,
12713 Object_Definition =>
12714 New_Occurrence_Of (Etype (Rel_Node), Loc),
12715 Expression => Expression (Rel_Node)));
12716 Finalization_Context := Last (Actions (Rel_Node));
12718 Analyze (Last (Actions (Rel_Node)));
12720 Set_Expression (Rel_Node, New_Occurrence_Of (Temp, Loc));
12721 Analyze (Expression (Rel_Node));
12725 Finalize_Always := False;
12726 Finalization_Context := Hook_Context;
12729 -- Step 1: Create the access type which provides a reference to the
12730 -- transient controlled object.
12732 if Is_Access_Type (Obj_Typ) then
12733 Desig_Typ := Directly_Designated_Type (Obj_Typ);
12735 Desig_Typ := Obj_Typ;
12738 Desig_Typ := Base_Type (Desig_Typ);
12741 -- Ann : access [all] <Desig_Typ>;
12743 Ptr_Id := Make_Temporary (Loc, 'A');
12745 Insert_Action (Hook_Context,
12746 Make_Full_Type_Declaration (Loc,
12747 Defining_Identifier => Ptr_Id,
12749 Make_Access_To_Object_Definition (Loc,
12750 All_Present => Ekind (Obj_Typ) = E_General_Access_Type,
12751 Subtype_Indication => New_Occurrence_Of (Desig_Typ, Loc))));
12753 -- Step 2: Create a temporary which acts as a hook to the transient
12754 -- controlled object. Generate:
12756 -- Temp : Ptr_Id := null;
12758 Temp_Id := Make_Temporary (Loc, 'T');
12760 Insert_Action (Hook_Context,
12761 Make_Object_Declaration (Loc,
12762 Defining_Identifier => Temp_Id,
12763 Object_Definition => New_Occurrence_Of (Ptr_Id, Loc)));
12765 -- Mark the temporary as created for the purposes of exporting the
12766 -- transient controlled object out of the expression_with_action or if
12767 -- expression. This signals the machinery in Build_Finalizer to treat
12768 -- this case specially.
12770 Set_Status_Flag_Or_Transient_Decl (Temp_Id, Decl);
12772 -- Step 3: Hook the transient object to the temporary
12774 -- This must be inserted right after the object declaration, so that
12775 -- the assignment is executed if, and only if, the object is actually
12776 -- created (whereas the declaration of the hook pointer, and the
12777 -- finalization call, may be inserted at an outer level, and may
12778 -- remain unused for some executions, if the actual creation of
12779 -- the object is conditional).
12781 -- The use of unchecked conversion / unrestricted access is needed to
12782 -- avoid an accessibility violation. Note that the finalization code is
12783 -- structured in such a way that the "hook" is processed only when it
12784 -- points to an existing object.
12786 if Is_Access_Type (Obj_Typ) then
12788 Unchecked_Convert_To (Ptr_Id, New_Occurrence_Of (Obj_Id, Loc));
12791 Make_Attribute_Reference (Loc,
12792 Prefix => New_Occurrence_Of (Obj_Id, Loc),
12793 Attribute_Name => Name_Unrestricted_Access);
12797 -- Temp := Ptr_Id (Obj_Id);
12799 -- Temp := Obj_Id'Unrestricted_Access;
12801 -- When the transient object is initialized by an aggregate, the hook
12802 -- must capture the object after the last component assignment takes
12803 -- place. Only then is the object fully initialized.
12805 if Ekind (Obj_Id) = E_Variable
12806 and then Present (Last_Aggregate_Assignment (Obj_Id))
12808 Temp_Ins := Last_Aggregate_Assignment (Obj_Id);
12810 -- Otherwise the hook seizes the related object immediately
12816 Insert_After_And_Analyze (Temp_Ins,
12817 Make_Assignment_Statement (Loc,
12818 Name => New_Occurrence_Of (Temp_Id, Loc),
12819 Expression => Expr));
12821 -- Step 4: Finalize the transient controlled object after the context
12822 -- has been evaluated/elaborated. Generate:
12824 -- if Temp /= null then
12825 -- [Deep_]Finalize (Temp.all);
12829 -- When the node is part of a return statement, there is no need to
12830 -- insert a finalization call, as the general finalization mechanism
12831 -- (see Build_Finalizer) would take care of the transient controlled
12832 -- object on subprogram exit. Note that it would also be impossible to
12833 -- insert the finalization code after the return statement as this will
12834 -- render it unreachable.
12836 if Nkind (Finalization_Context) /= N_Simple_Return_Statement then
12837 Fin_Stmts := New_List (
12840 Make_Explicit_Dereference (Loc,
12841 Prefix => New_Occurrence_Of (Temp_Id, Loc)),
12844 Make_Assignment_Statement (Loc,
12845 Name => New_Occurrence_Of (Temp_Id, Loc),
12846 Expression => Make_Null (Loc)));
12848 if not Finalize_Always then
12849 Fin_Stmts := New_List (
12850 Make_Implicit_If_Statement (Decl,
12853 Left_Opnd => New_Occurrence_Of (Temp_Id, Loc),
12854 Right_Opnd => Make_Null (Loc)),
12855 Then_Statements => Fin_Stmts));
12858 Insert_Actions_After (Finalization_Context, Fin_Stmts);
12860 end Process_Transient_Object;
12862 ------------------------
12863 -- Rewrite_Comparison --
12864 ------------------------
12866 procedure Rewrite_Comparison (N : Node_Id) is
12867 Warning_Generated : Boolean := False;
12868 -- Set to True if first pass with Assume_Valid generates a warning in
12869 -- which case we skip the second pass to avoid warning overloaded.
12872 -- Set to Standard_True or Standard_False
12875 if Nkind (N) = N_Type_Conversion then
12876 Rewrite_Comparison (Expression (N));
12879 elsif Nkind (N) not in N_Op_Compare then
12883 -- Now start looking at the comparison in detail. We potentially go
12884 -- through this loop twice. The first time, Assume_Valid is set False
12885 -- in the call to Compile_Time_Compare. If this call results in a
12886 -- clear result of always True or Always False, that's decisive and
12887 -- we are done. Otherwise we repeat the processing with Assume_Valid
12888 -- set to True to generate additional warnings. We can skip that step
12889 -- if Constant_Condition_Warnings is False.
12891 for AV in False .. True loop
12893 Typ : constant Entity_Id := Etype (N);
12894 Op1 : constant Node_Id := Left_Opnd (N);
12895 Op2 : constant Node_Id := Right_Opnd (N);
12897 Res : constant Compare_Result :=
12898 Compile_Time_Compare (Op1, Op2, Assume_Valid => AV);
12899 -- Res indicates if compare outcome can be compile time determined
12901 True_Result : Boolean;
12902 False_Result : Boolean;
12905 case N_Op_Compare (Nkind (N)) is
12907 True_Result := Res = EQ;
12908 False_Result := Res = LT or else Res = GT or else Res = NE;
12911 True_Result := Res in Compare_GE;
12912 False_Result := Res = LT;
12915 and then Constant_Condition_Warnings
12916 and then Comes_From_Source (Original_Node (N))
12917 and then Nkind (Original_Node (N)) = N_Op_Ge
12918 and then not In_Instance
12919 and then Is_Integer_Type (Etype (Left_Opnd (N)))
12920 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
12923 ("can never be greater than, could replace by ""'=""?c?",
12925 Warning_Generated := True;
12929 True_Result := Res = GT;
12930 False_Result := Res in Compare_LE;
12933 True_Result := Res = LT;
12934 False_Result := Res in Compare_GE;
12937 True_Result := Res in Compare_LE;
12938 False_Result := Res = GT;
12941 and then Constant_Condition_Warnings
12942 and then Comes_From_Source (Original_Node (N))
12943 and then Nkind (Original_Node (N)) = N_Op_Le
12944 and then not In_Instance
12945 and then Is_Integer_Type (Etype (Left_Opnd (N)))
12946 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
12949 ("can never be less than, could replace by ""'=""?c?", N);
12950 Warning_Generated := True;
12954 True_Result := Res = NE or else Res = GT or else Res = LT;
12955 False_Result := Res = EQ;
12958 -- If this is the first iteration, then we actually convert the
12959 -- comparison into True or False, if the result is certain.
12962 if True_Result or False_Result then
12963 Result := Boolean_Literals (True_Result);
12966 New_Occurrence_Of (Result, Sloc (N))));
12967 Analyze_And_Resolve (N, Typ);
12968 Warn_On_Known_Condition (N);
12972 -- If this is the second iteration (AV = True), and the original
12973 -- node comes from source and we are not in an instance, then give
12974 -- a warning if we know result would be True or False. Note: we
12975 -- know Constant_Condition_Warnings is set if we get here.
12977 elsif Comes_From_Source (Original_Node (N))
12978 and then not In_Instance
12980 if True_Result then
12982 ("condition can only be False if invalid values present??",
12984 elsif False_Result then
12986 ("condition can only be True if invalid values present??",
12992 -- Skip second iteration if not warning on constant conditions or
12993 -- if the first iteration already generated a warning of some kind or
12994 -- if we are in any case assuming all values are valid (so that the
12995 -- first iteration took care of the valid case).
12997 exit when not Constant_Condition_Warnings;
12998 exit when Warning_Generated;
12999 exit when Assume_No_Invalid_Values;
13001 end Rewrite_Comparison;
13003 ----------------------------
13004 -- Safe_In_Place_Array_Op --
13005 ----------------------------
13007 function Safe_In_Place_Array_Op
13010 Op2 : Node_Id) return Boolean
13012 Target : Entity_Id;
13014 function Is_Safe_Operand (Op : Node_Id) return Boolean;
13015 -- Operand is safe if it cannot overlap part of the target of the
13016 -- operation. If the operand and the target are identical, the operand
13017 -- is safe. The operand can be empty in the case of negation.
13019 function Is_Unaliased (N : Node_Id) return Boolean;
13020 -- Check that N is a stand-alone entity
13026 function Is_Unaliased (N : Node_Id) return Boolean is
13030 and then No (Address_Clause (Entity (N)))
13031 and then No (Renamed_Object (Entity (N)));
13034 ---------------------
13035 -- Is_Safe_Operand --
13036 ---------------------
13038 function Is_Safe_Operand (Op : Node_Id) return Boolean is
13043 elsif Is_Entity_Name (Op) then
13044 return Is_Unaliased (Op);
13046 elsif Nkind_In (Op, N_Indexed_Component, N_Selected_Component) then
13047 return Is_Unaliased (Prefix (Op));
13049 elsif Nkind (Op) = N_Slice then
13051 Is_Unaliased (Prefix (Op))
13052 and then Entity (Prefix (Op)) /= Target;
13054 elsif Nkind (Op) = N_Op_Not then
13055 return Is_Safe_Operand (Right_Opnd (Op));
13060 end Is_Safe_Operand;
13062 -- Start of processing for Safe_In_Place_Array_Op
13065 -- Skip this processing if the component size is different from system
13066 -- storage unit (since at least for NOT this would cause problems).
13068 if Component_Size (Etype (Lhs)) /= System_Storage_Unit then
13071 -- Cannot do in place stuff on VM_Target since cannot pass addresses
13073 elsif VM_Target /= No_VM then
13076 -- Cannot do in place stuff if non-standard Boolean representation
13078 elsif Has_Non_Standard_Rep (Component_Type (Etype (Lhs))) then
13081 elsif not Is_Unaliased (Lhs) then
13085 Target := Entity (Lhs);
13086 return Is_Safe_Operand (Op1) and then Is_Safe_Operand (Op2);
13088 end Safe_In_Place_Array_Op;
13090 -----------------------
13091 -- Tagged_Membership --
13092 -----------------------
13094 -- There are two different cases to consider depending on whether the right
13095 -- operand is a class-wide type or not. If not we just compare the actual
13096 -- tag of the left expr to the target type tag:
13098 -- Left_Expr.Tag = Right_Type'Tag;
13100 -- If it is a class-wide type we use the RT function CW_Membership which is
13101 -- usually implemented by looking in the ancestor tables contained in the
13102 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
13104 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
13105 -- function IW_Membership which is usually implemented by looking in the
13106 -- table of abstract interface types plus the ancestor table contained in
13107 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
13109 procedure Tagged_Membership
13111 SCIL_Node : out Node_Id;
13112 Result : out Node_Id)
13114 Left : constant Node_Id := Left_Opnd (N);
13115 Right : constant Node_Id := Right_Opnd (N);
13116 Loc : constant Source_Ptr := Sloc (N);
13118 Full_R_Typ : Entity_Id;
13119 Left_Type : Entity_Id;
13120 New_Node : Node_Id;
13121 Right_Type : Entity_Id;
13125 SCIL_Node := Empty;
13127 -- Handle entities from the limited view
13129 Left_Type := Available_View (Etype (Left));
13130 Right_Type := Available_View (Etype (Right));
13132 -- In the case where the type is an access type, the test is applied
13133 -- using the designated types (needed in Ada 2012 for implicit anonymous
13134 -- access conversions, for AI05-0149).
13136 if Is_Access_Type (Right_Type) then
13137 Left_Type := Designated_Type (Left_Type);
13138 Right_Type := Designated_Type (Right_Type);
13141 if Is_Class_Wide_Type (Left_Type) then
13142 Left_Type := Root_Type (Left_Type);
13145 if Is_Class_Wide_Type (Right_Type) then
13146 Full_R_Typ := Underlying_Type (Root_Type (Right_Type));
13148 Full_R_Typ := Underlying_Type (Right_Type);
13152 Make_Selected_Component (Loc,
13153 Prefix => Relocate_Node (Left),
13155 New_Occurrence_Of (First_Tag_Component (Left_Type), Loc));
13157 if Is_Class_Wide_Type (Right_Type) then
13159 -- No need to issue a run-time check if we statically know that the
13160 -- result of this membership test is always true. For example,
13161 -- considering the following declarations:
13163 -- type Iface is interface;
13164 -- type T is tagged null record;
13165 -- type DT is new T and Iface with null record;
13170 -- These membership tests are always true:
13173 -- Obj2 in T'Class;
13174 -- Obj2 in Iface'Class;
13176 -- We do not need to handle cases where the membership is illegal.
13179 -- Obj1 in DT'Class; -- Compile time error
13180 -- Obj1 in Iface'Class; -- Compile time error
13182 if not Is_Class_Wide_Type (Left_Type)
13183 and then (Is_Ancestor (Etype (Right_Type), Left_Type,
13184 Use_Full_View => True)
13185 or else (Is_Interface (Etype (Right_Type))
13186 and then Interface_Present_In_Ancestor
13188 Iface => Etype (Right_Type))))
13190 Result := New_Occurrence_Of (Standard_True, Loc);
13194 -- Ada 2005 (AI-251): Class-wide applied to interfaces
13196 if Is_Interface (Etype (Class_Wide_Type (Right_Type)))
13198 -- Support to: "Iface_CW_Typ in Typ'Class"
13200 or else Is_Interface (Left_Type)
13202 -- Issue error if IW_Membership operation not available in a
13203 -- configurable run time setting.
13205 if not RTE_Available (RE_IW_Membership) then
13207 ("dynamic membership test on interface types", N);
13213 Make_Function_Call (Loc,
13214 Name => New_Occurrence_Of (RTE (RE_IW_Membership), Loc),
13215 Parameter_Associations => New_List (
13216 Make_Attribute_Reference (Loc,
13218 Attribute_Name => Name_Address),
13219 New_Occurrence_Of (
13220 Node (First_Elmt (Access_Disp_Table (Full_R_Typ))),
13223 -- Ada 95: Normal case
13226 Build_CW_Membership (Loc,
13227 Obj_Tag_Node => Obj_Tag,
13229 New_Occurrence_Of (
13230 Node (First_Elmt (Access_Disp_Table (Full_R_Typ))), Loc),
13232 New_Node => New_Node);
13234 -- Generate the SCIL node for this class-wide membership test.
13235 -- Done here because the previous call to Build_CW_Membership
13236 -- relocates Obj_Tag.
13238 if Generate_SCIL then
13239 SCIL_Node := Make_SCIL_Membership_Test (Sloc (N));
13240 Set_SCIL_Entity (SCIL_Node, Etype (Right_Type));
13241 Set_SCIL_Tag_Value (SCIL_Node, Obj_Tag);
13244 Result := New_Node;
13247 -- Right_Type is not a class-wide type
13250 -- No need to check the tag of the object if Right_Typ is abstract
13252 if Is_Abstract_Type (Right_Type) then
13253 Result := New_Occurrence_Of (Standard_False, Loc);
13258 Left_Opnd => Obj_Tag,
13261 (Node (First_Elmt (Access_Disp_Table (Full_R_Typ))), Loc));
13264 end Tagged_Membership;
13266 ------------------------------
13267 -- Unary_Op_Validity_Checks --
13268 ------------------------------
13270 procedure Unary_Op_Validity_Checks (N : Node_Id) is
13272 if Validity_Checks_On and Validity_Check_Operands then
13273 Ensure_Valid (Right_Opnd (N));
13275 end Unary_Op_Validity_Checks;