1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, 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 Exp_VFpt; use Exp_VFpt;
46 with Freeze; use Freeze;
47 with Inline; use Inline;
49 with Namet; use Namet;
50 with Nlists; use Nlists;
51 with Nmake; use Nmake;
53 with Par_SCO; use Par_SCO;
54 with Restrict; use Restrict;
55 with Rident; use Rident;
56 with Rtsfind; use Rtsfind;
58 with Sem_Aux; use Sem_Aux;
59 with Sem_Cat; use Sem_Cat;
60 with Sem_Ch3; use Sem_Ch3;
61 with Sem_Ch8; use Sem_Ch8;
62 with Sem_Ch13; use Sem_Ch13;
63 with Sem_Eval; use Sem_Eval;
64 with Sem_Res; use Sem_Res;
65 with Sem_Type; use Sem_Type;
66 with Sem_Util; use Sem_Util;
67 with Sem_Warn; use Sem_Warn;
68 with Sinfo; use Sinfo;
69 with Snames; use Snames;
70 with Stand; use Stand;
71 with SCIL_LL; use SCIL_LL;
72 with Targparm; use Targparm;
73 with Tbuild; use Tbuild;
74 with Ttypes; use Ttypes;
75 with Uintp; use Uintp;
76 with Urealp; use Urealp;
77 with Validsw; use Validsw;
79 package body Exp_Ch4 is
81 -----------------------
82 -- Local Subprograms --
83 -----------------------
85 procedure Binary_Op_Validity_Checks (N : Node_Id);
86 pragma Inline (Binary_Op_Validity_Checks);
87 -- Performs validity checks for a binary operator
89 procedure Build_Boolean_Array_Proc_Call
93 -- If a boolean array assignment can be done in place, build call to
94 -- corresponding library procedure.
96 function Current_Anonymous_Master return Entity_Id;
97 -- Return the entity of the heterogeneous finalization master belonging to
98 -- the current unit (either function, package or procedure). This master
99 -- services all anonymous access-to-controlled types. If the current unit
100 -- does not have such master, create one.
102 procedure Displace_Allocator_Pointer (N : Node_Id);
103 -- Ada 2005 (AI-251): Subsidiary procedure to Expand_N_Allocator and
104 -- Expand_Allocator_Expression. Allocating class-wide interface objects
105 -- this routine displaces the pointer to the allocated object to reference
106 -- the component referencing the corresponding secondary dispatch table.
108 procedure Expand_Allocator_Expression (N : Node_Id);
109 -- Subsidiary to Expand_N_Allocator, for the case when the expression
110 -- is a qualified expression or an aggregate.
112 procedure Expand_Array_Comparison (N : Node_Id);
113 -- This routine handles expansion of the comparison operators (N_Op_Lt,
114 -- N_Op_Le, N_Op_Gt, N_Op_Ge) when operating on an array type. The basic
115 -- code for these operators is similar, differing only in the details of
116 -- the actual comparison call that is made. Special processing (call a
119 function Expand_Array_Equality
124 Typ : Entity_Id) return Node_Id;
125 -- Expand an array equality into a call to a function implementing this
126 -- equality, and a call to it. Loc is the location for the generated nodes.
127 -- Lhs and Rhs are the array expressions to be compared. Bodies is a list
128 -- on which to attach bodies of local functions that are created in the
129 -- process. It is the responsibility of the caller to insert those bodies
130 -- at the right place. Nod provides the Sloc value for the generated code.
131 -- Normally the types used for the generated equality routine are taken
132 -- from Lhs and Rhs. However, in some situations of generated code, the
133 -- Etype fields of Lhs and Rhs are not set yet. In such cases, Typ supplies
134 -- the type to be used for the formal parameters.
136 procedure Expand_Boolean_Operator (N : Node_Id);
137 -- Common expansion processing for Boolean operators (And, Or, Xor) for the
138 -- case of array type arguments.
140 procedure Expand_Short_Circuit_Operator (N : Node_Id);
141 -- Common expansion processing for short-circuit boolean operators
143 function Expand_Composite_Equality
148 Bodies : List_Id) return Node_Id;
149 -- Local recursive function used to expand equality for nested composite
150 -- types. Used by Expand_Record/Array_Equality, Bodies is a list on which
151 -- to attach bodies of local functions that are created in the process.
152 -- This is the responsibility of the caller to insert those bodies at the
153 -- right place. Nod provides the Sloc value for generated code. Lhs and Rhs
154 -- are the left and right sides for the comparison, and Typ is the type of
155 -- the arrays to compare.
157 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id);
158 -- Routine to expand concatenation of a sequence of two or more operands
159 -- (in the list Operands) and replace node Cnode with the result of the
160 -- concatenation. The operands can be of any appropriate type, and can
161 -- include both arrays and singleton elements.
163 procedure Fixup_Universal_Fixed_Operation (N : Node_Id);
164 -- N is a N_Op_Divide or N_Op_Multiply node whose result is universal
165 -- fixed. We do not have such a type at runtime, so the purpose of this
166 -- routine is to find the real type by looking up the tree. We also
167 -- determine if the operation must be rounded.
169 function Has_Inferable_Discriminants (N : Node_Id) return Boolean;
170 -- Ada 2005 (AI-216): A view of an Unchecked_Union object has inferable
171 -- discriminants if it has a constrained nominal type, unless the object
172 -- is a component of an enclosing Unchecked_Union object that is subject
173 -- to a per-object constraint and the enclosing object lacks inferable
176 -- An expression of an Unchecked_Union type has inferable discriminants
177 -- if it is either a name of an object with inferable discriminants or a
178 -- qualified expression whose subtype mark denotes a constrained subtype.
180 procedure Insert_Dereference_Action (N : Node_Id);
181 -- N is an expression whose type is an access. When the type of the
182 -- associated storage pool is derived from Checked_Pool, generate a
183 -- call to the 'Dereference' primitive operation.
185 function Make_Array_Comparison_Op
187 Nod : Node_Id) return Node_Id;
188 -- Comparisons between arrays are expanded in line. This function produces
189 -- the body of the implementation of (a > b), where a and b are one-
190 -- dimensional arrays of some discrete type. The original node is then
191 -- expanded into the appropriate call to this function. Nod provides the
192 -- Sloc value for the generated code.
194 function Make_Boolean_Array_Op
196 N : Node_Id) return Node_Id;
197 -- Boolean operations on boolean arrays are expanded in line. This function
198 -- produce the body for the node N, which is (a and b), (a or b), or (a xor
199 -- b). It is used only the normal case and not the packed case. The type
200 -- involved, Typ, is the Boolean array type, and the logical operations in
201 -- the body are simple boolean operations. Note that Typ is always a
202 -- constrained type (the caller has ensured this by using
203 -- Convert_To_Actual_Subtype if necessary).
205 procedure Optimize_Length_Comparison (N : Node_Id);
206 -- Given an expression, if it is of the form X'Length op N (or the other
207 -- way round), where N is known at compile time to be 0 or 1, and X is a
208 -- simple entity, and op is a comparison operator, optimizes it into a
209 -- comparison of First and Last.
211 procedure Rewrite_Comparison (N : Node_Id);
212 -- If N is the node for a comparison whose outcome can be determined at
213 -- compile time, then the node N can be rewritten with True or False. If
214 -- the outcome cannot be determined at compile time, the call has no
215 -- effect. If N is a type conversion, then this processing is applied to
216 -- its expression. If N is neither comparison nor a type conversion, the
217 -- call has no effect.
219 procedure Tagged_Membership
221 SCIL_Node : out Node_Id;
222 Result : out Node_Id);
223 -- Construct the expression corresponding to the tagged membership test.
224 -- Deals with a second operand being (or not) a class-wide type.
226 function Safe_In_Place_Array_Op
229 Op2 : Node_Id) return Boolean;
230 -- In the context of an assignment, where the right-hand side is a boolean
231 -- operation on arrays, check whether operation can be performed in place.
233 procedure Unary_Op_Validity_Checks (N : Node_Id);
234 pragma Inline (Unary_Op_Validity_Checks);
235 -- Performs validity checks for a unary operator
237 -------------------------------
238 -- Binary_Op_Validity_Checks --
239 -------------------------------
241 procedure Binary_Op_Validity_Checks (N : Node_Id) is
243 if Validity_Checks_On and Validity_Check_Operands then
244 Ensure_Valid (Left_Opnd (N));
245 Ensure_Valid (Right_Opnd (N));
247 end Binary_Op_Validity_Checks;
249 ------------------------------------
250 -- Build_Boolean_Array_Proc_Call --
251 ------------------------------------
253 procedure Build_Boolean_Array_Proc_Call
258 Loc : constant Source_Ptr := Sloc (N);
259 Kind : constant Node_Kind := Nkind (Expression (N));
260 Target : constant Node_Id :=
261 Make_Attribute_Reference (Loc,
263 Attribute_Name => Name_Address);
265 Arg1 : Node_Id := Op1;
266 Arg2 : Node_Id := Op2;
268 Proc_Name : Entity_Id;
271 if Kind = N_Op_Not then
272 if Nkind (Op1) in N_Binary_Op then
274 -- Use negated version of the binary operators
276 if Nkind (Op1) = N_Op_And then
277 Proc_Name := RTE (RE_Vector_Nand);
279 elsif Nkind (Op1) = N_Op_Or then
280 Proc_Name := RTE (RE_Vector_Nor);
282 else pragma Assert (Nkind (Op1) = N_Op_Xor);
283 Proc_Name := RTE (RE_Vector_Xor);
287 Make_Procedure_Call_Statement (Loc,
288 Name => New_Occurrence_Of (Proc_Name, Loc),
290 Parameter_Associations => New_List (
292 Make_Attribute_Reference (Loc,
293 Prefix => Left_Opnd (Op1),
294 Attribute_Name => Name_Address),
296 Make_Attribute_Reference (Loc,
297 Prefix => Right_Opnd (Op1),
298 Attribute_Name => Name_Address),
300 Make_Attribute_Reference (Loc,
301 Prefix => Left_Opnd (Op1),
302 Attribute_Name => Name_Length)));
305 Proc_Name := RTE (RE_Vector_Not);
308 Make_Procedure_Call_Statement (Loc,
309 Name => New_Occurrence_Of (Proc_Name, Loc),
310 Parameter_Associations => New_List (
313 Make_Attribute_Reference (Loc,
315 Attribute_Name => Name_Address),
317 Make_Attribute_Reference (Loc,
319 Attribute_Name => Name_Length)));
323 -- We use the following equivalences:
325 -- (not X) or (not Y) = not (X and Y) = Nand (X, Y)
326 -- (not X) and (not Y) = not (X or Y) = Nor (X, Y)
327 -- (not X) xor (not Y) = X xor Y
328 -- X xor (not Y) = not (X xor Y) = Nxor (X, Y)
330 if Nkind (Op1) = N_Op_Not then
331 Arg1 := Right_Opnd (Op1);
332 Arg2 := Right_Opnd (Op2);
333 if Kind = N_Op_And then
334 Proc_Name := RTE (RE_Vector_Nor);
335 elsif Kind = N_Op_Or then
336 Proc_Name := RTE (RE_Vector_Nand);
338 Proc_Name := RTE (RE_Vector_Xor);
342 if Kind = N_Op_And then
343 Proc_Name := RTE (RE_Vector_And);
344 elsif Kind = N_Op_Or then
345 Proc_Name := RTE (RE_Vector_Or);
346 elsif Nkind (Op2) = N_Op_Not then
347 Proc_Name := RTE (RE_Vector_Nxor);
348 Arg2 := Right_Opnd (Op2);
350 Proc_Name := RTE (RE_Vector_Xor);
355 Make_Procedure_Call_Statement (Loc,
356 Name => New_Occurrence_Of (Proc_Name, Loc),
357 Parameter_Associations => New_List (
359 Make_Attribute_Reference (Loc,
361 Attribute_Name => Name_Address),
362 Make_Attribute_Reference (Loc,
364 Attribute_Name => Name_Address),
365 Make_Attribute_Reference (Loc,
367 Attribute_Name => Name_Length)));
370 Rewrite (N, Call_Node);
374 when RE_Not_Available =>
376 end Build_Boolean_Array_Proc_Call;
378 ------------------------------
379 -- Current_Anonymous_Master --
380 ------------------------------
382 function Current_Anonymous_Master return Entity_Id is
390 Unit_Id := Cunit_Entity (Current_Sem_Unit);
392 -- Find the entity of the current unit
394 if Ekind (Unit_Id) = E_Subprogram_Body then
396 -- When processing subprogram bodies, the proper scope is always that
399 Subp_Body := Unit_Id;
400 while Present (Subp_Body)
401 and then Nkind (Subp_Body) /= N_Subprogram_Body
403 Subp_Body := Parent (Subp_Body);
406 Unit_Id := Corresponding_Spec (Subp_Body);
409 Loc := Sloc (Unit_Id);
410 Unit_Decl := Unit (Cunit (Current_Sem_Unit));
412 -- Find the declarations list of the current unit
414 if Nkind (Unit_Decl) = N_Package_Declaration then
415 Unit_Decl := Specification (Unit_Decl);
416 Decls := Visible_Declarations (Unit_Decl);
419 Decls := New_List (Make_Null_Statement (Loc));
420 Set_Visible_Declarations (Unit_Decl, Decls);
422 elsif Is_Empty_List (Decls) then
423 Append_To (Decls, Make_Null_Statement (Loc));
427 Decls := Declarations (Unit_Decl);
430 Decls := New_List (Make_Null_Statement (Loc));
431 Set_Declarations (Unit_Decl, Decls);
433 elsif Is_Empty_List (Decls) then
434 Append_To (Decls, Make_Null_Statement (Loc));
438 -- The current unit has an existing anonymous master, traverse its
439 -- declarations and locate the entity.
441 if Has_Anonymous_Master (Unit_Id) then
444 Fin_Mas_Id : Entity_Id;
447 Decl := First (Decls);
448 while Present (Decl) loop
450 -- Look for the first variable in the declarations whole type
451 -- is Finalization_Master.
453 if Nkind (Decl) = N_Object_Declaration then
454 Fin_Mas_Id := Defining_Identifier (Decl);
456 if Ekind (Fin_Mas_Id) = E_Variable
457 and then Etype (Fin_Mas_Id) = RTE (RE_Finalization_Master)
466 -- The master was not found even though the unit was labeled as
472 -- Create a new anonymous master
476 First_Decl : constant Node_Id := First (Decls);
478 Fin_Mas_Id : Entity_Id;
481 -- Since the master and its associated initialization is inserted
482 -- at top level, use the scope of the unit when analyzing.
484 Push_Scope (Unit_Id);
486 -- Create the finalization master
489 Make_Defining_Identifier (Loc,
490 Chars => New_External_Name (Chars (Unit_Id), "AM"));
493 -- <Fin_Mas_Id> : Finalization_Master;
496 Make_Object_Declaration (Loc,
497 Defining_Identifier => Fin_Mas_Id,
499 New_Reference_To (RTE (RE_Finalization_Master), Loc));
501 Insert_Before_And_Analyze (First_Decl, Action);
503 -- Mark the unit to prevent the generation of multiple masters
505 Set_Has_Anonymous_Master (Unit_Id);
507 -- Do not set the base pool and mode of operation on .NET/JVM
508 -- since those targets do not support pools and all VM masters
509 -- are heterogeneous by default.
511 if VM_Target = No_VM then
515 -- (<Fin_Mas_Id>, Global_Pool_Object'Unrestricted_Access);
518 Make_Procedure_Call_Statement (Loc,
520 New_Reference_To (RTE (RE_Set_Base_Pool), Loc),
522 Parameter_Associations => New_List (
523 New_Reference_To (Fin_Mas_Id, Loc),
524 Make_Attribute_Reference (Loc,
526 New_Reference_To (RTE (RE_Global_Pool_Object), Loc),
527 Attribute_Name => Name_Unrestricted_Access)));
529 Insert_Before_And_Analyze (First_Decl, Action);
532 -- Set_Is_Heterogeneous (<Fin_Mas_Id>);
535 Make_Procedure_Call_Statement (Loc,
537 New_Reference_To (RTE (RE_Set_Is_Heterogeneous), Loc),
538 Parameter_Associations => New_List (
539 New_Reference_To (Fin_Mas_Id, Loc)));
541 Insert_Before_And_Analyze (First_Decl, Action);
544 -- Restore the original state of the scope stack
551 end Current_Anonymous_Master;
553 --------------------------------
554 -- Displace_Allocator_Pointer --
555 --------------------------------
557 procedure Displace_Allocator_Pointer (N : Node_Id) is
558 Loc : constant Source_Ptr := Sloc (N);
559 Orig_Node : constant Node_Id := Original_Node (N);
565 -- Do nothing in case of VM targets: the virtual machine will handle
566 -- interfaces directly.
568 if not Tagged_Type_Expansion then
572 pragma Assert (Nkind (N) = N_Identifier
573 and then Nkind (Orig_Node) = N_Allocator);
575 PtrT := Etype (Orig_Node);
576 Dtyp := Available_View (Designated_Type (PtrT));
577 Etyp := Etype (Expression (Orig_Node));
579 if Is_Class_Wide_Type (Dtyp)
580 and then Is_Interface (Dtyp)
582 -- If the type of the allocator expression is not an interface type
583 -- we can generate code to reference the record component containing
584 -- the pointer to the secondary dispatch table.
586 if not Is_Interface (Etyp) then
588 Saved_Typ : constant Entity_Id := Etype (Orig_Node);
591 -- 1) Get access to the allocated object
594 Make_Explicit_Dereference (Loc,
599 -- 2) Add the conversion to displace the pointer to reference
600 -- the secondary dispatch table.
602 Rewrite (N, Convert_To (Dtyp, Relocate_Node (N)));
603 Analyze_And_Resolve (N, Dtyp);
605 -- 3) The 'access to the secondary dispatch table will be used
606 -- as the value returned by the allocator.
609 Make_Attribute_Reference (Loc,
610 Prefix => Relocate_Node (N),
611 Attribute_Name => Name_Access));
612 Set_Etype (N, Saved_Typ);
616 -- If the type of the allocator expression is an interface type we
617 -- generate a run-time call to displace "this" to reference the
618 -- component containing the pointer to the secondary dispatch table
619 -- or else raise Constraint_Error if the actual object does not
620 -- implement the target interface. This case corresponds with the
621 -- following example:
623 -- function Op (Obj : Iface_1'Class) return access Iface_2'Class is
625 -- return new Iface_2'Class'(Obj);
630 Unchecked_Convert_To (PtrT,
631 Make_Function_Call (Loc,
632 Name => New_Reference_To (RTE (RE_Displace), Loc),
633 Parameter_Associations => New_List (
634 Unchecked_Convert_To (RTE (RE_Address),
640 (Access_Disp_Table (Etype (Base_Type (Dtyp))))),
642 Analyze_And_Resolve (N, PtrT);
645 end Displace_Allocator_Pointer;
647 ---------------------------------
648 -- Expand_Allocator_Expression --
649 ---------------------------------
651 procedure Expand_Allocator_Expression (N : Node_Id) is
652 Loc : constant Source_Ptr := Sloc (N);
653 Exp : constant Node_Id := Expression (Expression (N));
654 PtrT : constant Entity_Id := Etype (N);
655 DesigT : constant Entity_Id := Designated_Type (PtrT);
657 procedure Apply_Accessibility_Check
659 Built_In_Place : Boolean := False);
660 -- Ada 2005 (AI-344): For an allocator with a class-wide designated
661 -- type, generate an accessibility check to verify that the level of the
662 -- type of the created object is not deeper than the level of the access
663 -- type. If the type of the qualified expression is class- wide, then
664 -- always generate the check (except in the case where it is known to be
665 -- unnecessary, see comment below). Otherwise, only generate the check
666 -- if the level of the qualified expression type is statically deeper
667 -- than the access type.
669 -- Although the static accessibility will generally have been performed
670 -- as a legality check, it won't have been done in cases where the
671 -- allocator appears in generic body, so a run-time check is needed in
672 -- general. One special case is when the access type is declared in the
673 -- same scope as the class-wide allocator, in which case the check can
674 -- never fail, so it need not be generated.
676 -- As an open issue, there seem to be cases where the static level
677 -- associated with the class-wide object's underlying type is not
678 -- sufficient to perform the proper accessibility check, such as for
679 -- allocators in nested subprograms or accept statements initialized by
680 -- class-wide formals when the actual originates outside at a deeper
681 -- static level. The nested subprogram case might require passing
682 -- accessibility levels along with class-wide parameters, and the task
683 -- case seems to be an actual gap in the language rules that needs to
684 -- be fixed by the ARG. ???
686 -------------------------------
687 -- Apply_Accessibility_Check --
688 -------------------------------
690 procedure Apply_Accessibility_Check
692 Built_In_Place : Boolean := False)
697 if Ada_Version >= Ada_2005
698 and then Is_Class_Wide_Type (DesigT)
699 and then not Scope_Suppress (Accessibility_Check)
701 (Type_Access_Level (Etype (Exp)) > Type_Access_Level (PtrT)
703 (Is_Class_Wide_Type (Etype (Exp))
704 and then Scope (PtrT) /= Current_Scope))
706 -- If the allocator was built in place Ref is already a reference
707 -- to the access object initialized to the result of the allocator
708 -- (see Exp_Ch6.Make_Build_In_Place_Call_In_Allocator). Otherwise
709 -- it is the entity associated with the object containing the
710 -- address of the allocated object.
712 if Built_In_Place then
713 New_Node := New_Copy (Ref);
715 New_Node := New_Reference_To (Ref, Loc);
719 Make_Attribute_Reference (Loc,
721 Attribute_Name => Name_Tag);
723 if Tagged_Type_Expansion then
724 New_Node := Build_Get_Access_Level (Loc, New_Node);
726 elsif VM_Target /= No_VM then
728 Make_Function_Call (Loc,
729 Name => New_Reference_To (RTE (RE_Get_Access_Level), Loc),
730 Parameter_Associations => New_List (New_Node));
732 -- Cannot generate the runtime check
739 Make_Raise_Program_Error (Loc,
742 Left_Opnd => New_Node,
744 Make_Integer_Literal (Loc, Type_Access_Level (PtrT))),
745 Reason => PE_Accessibility_Check_Failed));
747 end Apply_Accessibility_Check;
751 Aggr_In_Place : constant Boolean := Is_Delayed_Aggregate (Exp);
752 Indic : constant Node_Id := Subtype_Mark (Expression (N));
753 T : constant Entity_Id := Entity (Indic);
755 Tag_Assign : Node_Id;
759 TagT : Entity_Id := Empty;
760 -- Type used as source for tag assignment
762 TagR : Node_Id := Empty;
763 -- Target reference for tag assignment
765 -- Start of processing for Expand_Allocator_Expression
768 -- In the case of an Ada2012 allocator whose initial value comes from a
769 -- function call, pass "the accessibility level determined by the point
770 -- of call" (AI05-0234) to the function. Conceptually, this belongs in
771 -- Expand_Call but it couldn't be done there (because the Etype of the
772 -- allocator wasn't set then) so we generate the parameter here. See
773 -- the Boolean variable Defer in (a block within) Expand_Call.
775 if Ada_Version >= Ada_2012 and then Nkind (Exp) = N_Function_Call then
780 if Nkind (Name (Exp)) = N_Explicit_Dereference then
781 Subp := Designated_Type (Etype (Prefix (Name (Exp))));
783 Subp := Entity (Name (Exp));
786 Subp := Ultimate_Alias (Subp);
788 if Present (Extra_Accessibility_Of_Result (Subp)) then
789 Add_Extra_Actual_To_Call
790 (Subprogram_Call => Exp,
791 Extra_Formal => Extra_Accessibility_Of_Result (Subp),
792 Extra_Actual => Dynamic_Accessibility_Level (PtrT));
797 -- Would be nice to comment the branches of this very long if ???
799 if Is_Tagged_Type (T) or else Needs_Finalization (T) then
800 if Is_CPP_Constructor_Call (Exp) then
803 -- Pnnn : constant ptr_T := new (T);
804 -- Init (Pnnn.all,...);
806 -- Allocate the object without an expression
808 Node := Relocate_Node (N);
809 Set_Expression (Node, New_Reference_To (Etype (Exp), Loc));
811 -- Avoid its expansion to avoid generating a call to the default
816 Temp := Make_Temporary (Loc, 'P', N);
819 Make_Object_Declaration (Loc,
820 Defining_Identifier => Temp,
821 Constant_Present => True,
822 Object_Definition => New_Reference_To (PtrT, Loc),
824 Insert_Action (N, Temp_Decl);
826 Apply_Accessibility_Check (Temp);
828 -- Locate the enclosing list and insert the C++ constructor call
835 while not Is_List_Member (P) loop
839 Insert_List_After_And_Analyze (P,
840 Build_Initialization_Call (Loc,
842 Make_Explicit_Dereference (Loc,
843 Prefix => New_Reference_To (Temp, Loc)),
845 Constructor_Ref => Exp));
848 Rewrite (N, New_Reference_To (Temp, Loc));
849 Analyze_And_Resolve (N, PtrT);
853 -- Ada 2005 (AI-318-02): If the initialization expression is a call
854 -- to a build-in-place function, then access to the allocated object
855 -- must be passed to the function. Currently we limit such functions
856 -- to those with constrained limited result subtypes, but eventually
857 -- we plan to expand the allowed forms of functions that are treated
858 -- as build-in-place.
860 if Ada_Version >= Ada_2005
861 and then Is_Build_In_Place_Function_Call (Exp)
863 Make_Build_In_Place_Call_In_Allocator (N, Exp);
864 Apply_Accessibility_Check (N, Built_In_Place => True);
868 -- Actions inserted before:
869 -- Temp : constant ptr_T := new T'(Expression);
870 -- Temp._tag = T'tag; -- when not class-wide
871 -- [Deep_]Adjust (Temp.all);
873 -- We analyze by hand the new internal allocator to avoid any
874 -- recursion and inappropriate call to Initialize
876 -- We don't want to remove side effects when the expression must be
877 -- built in place. In the case of a build-in-place function call,
878 -- that could lead to a duplication of the call, which was already
879 -- substituted for the allocator.
881 if not Aggr_In_Place then
882 Remove_Side_Effects (Exp);
885 Temp := Make_Temporary (Loc, 'P', N);
887 -- For a class wide allocation generate the following code:
889 -- type Equiv_Record is record ... end record;
890 -- implicit subtype CW is <Class_Wide_Subytpe>;
891 -- temp : PtrT := new CW'(CW!(expr));
893 if Is_Class_Wide_Type (T) then
894 Expand_Subtype_From_Expr (Empty, T, Indic, Exp);
896 -- Ada 2005 (AI-251): If the expression is a class-wide interface
897 -- object we generate code to move up "this" to reference the
898 -- base of the object before allocating the new object.
900 -- Note that Exp'Address is recursively expanded into a call
901 -- to Base_Address (Exp.Tag)
903 if Is_Class_Wide_Type (Etype (Exp))
904 and then Is_Interface (Etype (Exp))
905 and then Tagged_Type_Expansion
909 Unchecked_Convert_To (Entity (Indic),
910 Make_Explicit_Dereference (Loc,
911 Unchecked_Convert_To (RTE (RE_Tag_Ptr),
912 Make_Attribute_Reference (Loc,
914 Attribute_Name => Name_Address)))));
918 Unchecked_Convert_To (Entity (Indic), Exp));
921 Analyze_And_Resolve (Expression (N), Entity (Indic));
924 -- Processing for allocators returning non-interface types
926 if not Is_Interface (Directly_Designated_Type (PtrT)) then
927 if Aggr_In_Place then
929 Make_Object_Declaration (Loc,
930 Defining_Identifier => Temp,
931 Object_Definition => New_Reference_To (PtrT, Loc),
935 New_Reference_To (Etype (Exp), Loc)));
937 -- Copy the Comes_From_Source flag for the allocator we just
938 -- built, since logically this allocator is a replacement of
939 -- the original allocator node. This is for proper handling of
940 -- restriction No_Implicit_Heap_Allocations.
942 Set_Comes_From_Source
943 (Expression (Temp_Decl), Comes_From_Source (N));
945 Set_No_Initialization (Expression (Temp_Decl));
946 Insert_Action (N, Temp_Decl);
948 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
949 Convert_Aggr_In_Allocator (N, Temp_Decl, Exp);
951 -- Attach the object to the associated finalization master.
952 -- This is done manually on .NET/JVM since those compilers do
953 -- no support pools and can't benefit from internally generated
954 -- Allocate / Deallocate procedures.
956 if VM_Target /= No_VM
957 and then Is_Controlled (DesigT)
958 and then Present (Finalization_Master (PtrT))
963 New_Reference_To (Temp, Loc),
968 Node := Relocate_Node (N);
972 Make_Object_Declaration (Loc,
973 Defining_Identifier => Temp,
974 Constant_Present => True,
975 Object_Definition => New_Reference_To (PtrT, Loc),
978 Insert_Action (N, Temp_Decl);
979 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
981 -- Attach the object to the associated finalization master.
982 -- This is done manually on .NET/JVM since those compilers do
983 -- no support pools and can't benefit from internally generated
984 -- Allocate / Deallocate procedures.
986 if VM_Target /= No_VM
987 and then Is_Controlled (DesigT)
988 and then Present (Finalization_Master (PtrT))
993 New_Reference_To (Temp, Loc),
998 -- Ada 2005 (AI-251): Handle allocators whose designated type is an
999 -- interface type. In this case we use the type of the qualified
1000 -- expression to allocate the object.
1004 Def_Id : constant Entity_Id := Make_Temporary (Loc, 'T');
1009 Make_Full_Type_Declaration (Loc,
1010 Defining_Identifier => Def_Id,
1012 Make_Access_To_Object_Definition (Loc,
1013 All_Present => True,
1014 Null_Exclusion_Present => False,
1015 Constant_Present => False,
1016 Subtype_Indication =>
1017 New_Reference_To (Etype (Exp), Loc)));
1019 Insert_Action (N, New_Decl);
1021 -- Inherit the allocation-related attributes from the original
1024 Set_Finalization_Master (Def_Id, Finalization_Master (PtrT));
1026 Set_Associated_Storage_Pool (Def_Id,
1027 Associated_Storage_Pool (PtrT));
1029 -- Declare the object using the previous type declaration
1031 if Aggr_In_Place then
1033 Make_Object_Declaration (Loc,
1034 Defining_Identifier => Temp,
1035 Object_Definition => New_Reference_To (Def_Id, Loc),
1037 Make_Allocator (Loc,
1038 New_Reference_To (Etype (Exp), Loc)));
1040 -- Copy the Comes_From_Source flag for the allocator we just
1041 -- built, since logically this allocator is a replacement of
1042 -- the original allocator node. This is for proper handling
1043 -- of restriction No_Implicit_Heap_Allocations.
1045 Set_Comes_From_Source
1046 (Expression (Temp_Decl), Comes_From_Source (N));
1048 Set_No_Initialization (Expression (Temp_Decl));
1049 Insert_Action (N, Temp_Decl);
1051 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1052 Convert_Aggr_In_Allocator (N, Temp_Decl, Exp);
1055 Node := Relocate_Node (N);
1056 Set_Analyzed (Node);
1059 Make_Object_Declaration (Loc,
1060 Defining_Identifier => Temp,
1061 Constant_Present => True,
1062 Object_Definition => New_Reference_To (Def_Id, Loc),
1063 Expression => Node);
1065 Insert_Action (N, Temp_Decl);
1066 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1069 -- Generate an additional object containing the address of the
1070 -- returned object. The type of this second object declaration
1071 -- is the correct type required for the common processing that
1072 -- is still performed by this subprogram. The displacement of
1073 -- this pointer to reference the component associated with the
1074 -- interface type will be done at the end of common processing.
1077 Make_Object_Declaration (Loc,
1078 Defining_Identifier => Make_Temporary (Loc, 'P'),
1079 Object_Definition => New_Reference_To (PtrT, Loc),
1081 Unchecked_Convert_To (PtrT,
1082 New_Reference_To (Temp, Loc)));
1084 Insert_Action (N, New_Decl);
1086 Temp_Decl := New_Decl;
1087 Temp := Defining_Identifier (New_Decl);
1091 Apply_Accessibility_Check (Temp);
1093 -- Generate the tag assignment
1095 -- Suppress the tag assignment when VM_Target because VM tags are
1096 -- represented implicitly in objects.
1098 if not Tagged_Type_Expansion then
1101 -- Ada 2005 (AI-251): Suppress the tag assignment with class-wide
1102 -- interface objects because in this case the tag does not change.
1104 elsif Is_Interface (Directly_Designated_Type (Etype (N))) then
1105 pragma Assert (Is_Class_Wide_Type
1106 (Directly_Designated_Type (Etype (N))));
1109 elsif Is_Tagged_Type (T) and then not Is_Class_Wide_Type (T) then
1111 TagR := New_Reference_To (Temp, Loc);
1113 elsif Is_Private_Type (T)
1114 and then Is_Tagged_Type (Underlying_Type (T))
1116 TagT := Underlying_Type (T);
1118 Unchecked_Convert_To (Underlying_Type (T),
1119 Make_Explicit_Dereference (Loc,
1120 Prefix => New_Reference_To (Temp, Loc)));
1123 if Present (TagT) then
1125 Full_T : constant Entity_Id := Underlying_Type (TagT);
1128 Make_Assignment_Statement (Loc,
1130 Make_Selected_Component (Loc,
1133 New_Reference_To (First_Tag_Component (Full_T), Loc)),
1135 Unchecked_Convert_To (RTE (RE_Tag),
1138 (First_Elmt (Access_Disp_Table (Full_T))), Loc)));
1141 -- The previous assignment has to be done in any case
1143 Set_Assignment_OK (Name (Tag_Assign));
1144 Insert_Action (N, Tag_Assign);
1147 if Needs_Finalization (DesigT)
1148 and then Needs_Finalization (T)
1150 -- Generate an Adjust call if the object will be moved. In Ada
1151 -- 2005, the object may be inherently limited, in which case
1152 -- there is no Adjust procedure, and the object is built in
1153 -- place. In Ada 95, the object can be limited but not
1154 -- inherently limited if this allocator came from a return
1155 -- statement (we're allocating the result on the secondary
1156 -- stack). In that case, the object will be moved, so we _do_
1159 if not Aggr_In_Place
1160 and then not Is_Immutably_Limited_Type (T)
1166 -- An unchecked conversion is needed in the classwide
1167 -- case because the designated type can be an ancestor
1168 -- of the subtype mark of the allocator.
1170 Unchecked_Convert_To (T,
1171 Make_Explicit_Dereference (Loc,
1172 Prefix => New_Reference_To (Temp, Loc))),
1177 -- Set_Finalize_Address (<PtrT>FM, <T>FD'Unrestricted_Access);
1179 -- Do not generate this call in the following cases:
1181 -- * .NET/JVM - these targets do not support address arithmetic
1182 -- and unchecked conversion, key elements of Finalize_Address.
1184 -- * Alfa mode - the call is useless and results in unwanted
1187 -- * CodePeer mode - TSS primitive Finalize_Address is not
1188 -- created in this mode.
1190 if VM_Target = No_VM
1191 and then not Alfa_Mode
1192 and then not CodePeer_Mode
1193 and then Present (Finalization_Master (PtrT))
1194 and then Present (Temp_Decl)
1195 and then Nkind (Expression (Temp_Decl)) = N_Allocator
1198 Make_Set_Finalize_Address_Call
1205 Rewrite (N, New_Reference_To (Temp, Loc));
1206 Analyze_And_Resolve (N, PtrT);
1208 -- Ada 2005 (AI-251): Displace the pointer to reference the record
1209 -- component containing the secondary dispatch table of the interface
1212 if Is_Interface (Directly_Designated_Type (PtrT)) then
1213 Displace_Allocator_Pointer (N);
1216 elsif Aggr_In_Place then
1217 Temp := Make_Temporary (Loc, 'P', N);
1219 Make_Object_Declaration (Loc,
1220 Defining_Identifier => Temp,
1221 Object_Definition => New_Reference_To (PtrT, Loc),
1223 Make_Allocator (Loc,
1224 Expression => New_Reference_To (Etype (Exp), Loc)));
1226 -- Copy the Comes_From_Source flag for the allocator we just built,
1227 -- since logically this allocator is a replacement of the original
1228 -- allocator node. This is for proper handling of restriction
1229 -- No_Implicit_Heap_Allocations.
1231 Set_Comes_From_Source
1232 (Expression (Temp_Decl), Comes_From_Source (N));
1234 Set_No_Initialization (Expression (Temp_Decl));
1235 Insert_Action (N, Temp_Decl);
1237 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
1238 Convert_Aggr_In_Allocator (N, Temp_Decl, Exp);
1240 -- Attach the object to the associated finalization master. Thisis
1241 -- done manually on .NET/JVM since those compilers do no support
1242 -- pools and cannot benefit from internally generated Allocate and
1243 -- Deallocate procedures.
1245 if VM_Target /= No_VM
1246 and then Is_Controlled (DesigT)
1247 and then Present (Finalization_Master (PtrT))
1251 (Obj_Ref => New_Reference_To (Temp, Loc),
1255 Rewrite (N, New_Reference_To (Temp, Loc));
1256 Analyze_And_Resolve (N, PtrT);
1258 elsif Is_Access_Type (T)
1259 and then Can_Never_Be_Null (T)
1261 Install_Null_Excluding_Check (Exp);
1263 elsif Is_Access_Type (DesigT)
1264 and then Nkind (Exp) = N_Allocator
1265 and then Nkind (Expression (Exp)) /= N_Qualified_Expression
1267 -- Apply constraint to designated subtype indication
1269 Apply_Constraint_Check (Expression (Exp),
1270 Designated_Type (DesigT),
1271 No_Sliding => True);
1273 if Nkind (Expression (Exp)) = N_Raise_Constraint_Error then
1275 -- Propagate constraint_error to enclosing allocator
1277 Rewrite (Exp, New_Copy (Expression (Exp)));
1281 Build_Allocate_Deallocate_Proc (N, True);
1284 -- type A is access T1;
1285 -- X : A := new T2'(...);
1286 -- T1 and T2 can be different subtypes, and we might need to check
1287 -- both constraints. First check against the type of the qualified
1290 Apply_Constraint_Check (Exp, T, No_Sliding => True);
1292 if Do_Range_Check (Exp) then
1293 Set_Do_Range_Check (Exp, False);
1294 Generate_Range_Check (Exp, DesigT, CE_Range_Check_Failed);
1297 -- A check is also needed in cases where the designated subtype is
1298 -- constrained and differs from the subtype given in the qualified
1299 -- expression. Note that the check on the qualified expression does
1300 -- not allow sliding, but this check does (a relaxation from Ada 83).
1302 if Is_Constrained (DesigT)
1303 and then not Subtypes_Statically_Match (T, DesigT)
1305 Apply_Constraint_Check
1306 (Exp, DesigT, No_Sliding => False);
1308 if Do_Range_Check (Exp) then
1309 Set_Do_Range_Check (Exp, False);
1310 Generate_Range_Check (Exp, DesigT, CE_Range_Check_Failed);
1314 -- For an access to unconstrained packed array, GIGI needs to see an
1315 -- expression with a constrained subtype in order to compute the
1316 -- proper size for the allocator.
1318 if Is_Array_Type (T)
1319 and then not Is_Constrained (T)
1320 and then Is_Packed (T)
1323 ConstrT : constant Entity_Id := Make_Temporary (Loc, 'A');
1324 Internal_Exp : constant Node_Id := Relocate_Node (Exp);
1327 Make_Subtype_Declaration (Loc,
1328 Defining_Identifier => ConstrT,
1329 Subtype_Indication =>
1330 Make_Subtype_From_Expr (Internal_Exp, T)));
1331 Freeze_Itype (ConstrT, Exp);
1332 Rewrite (Exp, OK_Convert_To (ConstrT, Internal_Exp));
1336 -- Ada 2005 (AI-318-02): If the initialization expression is a call
1337 -- to a build-in-place function, then access to the allocated object
1338 -- must be passed to the function. Currently we limit such functions
1339 -- to those with constrained limited result subtypes, but eventually
1340 -- we plan to expand the allowed forms of functions that are treated
1341 -- as build-in-place.
1343 if Ada_Version >= Ada_2005
1344 and then Is_Build_In_Place_Function_Call (Exp)
1346 Make_Build_In_Place_Call_In_Allocator (N, Exp);
1351 when RE_Not_Available =>
1353 end Expand_Allocator_Expression;
1355 -----------------------------
1356 -- Expand_Array_Comparison --
1357 -----------------------------
1359 -- Expansion is only required in the case of array types. For the unpacked
1360 -- case, an appropriate runtime routine is called. For packed cases, and
1361 -- also in some other cases where a runtime routine cannot be called, the
1362 -- form of the expansion is:
1364 -- [body for greater_nn; boolean_expression]
1366 -- The body is built by Make_Array_Comparison_Op, and the form of the
1367 -- Boolean expression depends on the operator involved.
1369 procedure Expand_Array_Comparison (N : Node_Id) is
1370 Loc : constant Source_Ptr := Sloc (N);
1371 Op1 : Node_Id := Left_Opnd (N);
1372 Op2 : Node_Id := Right_Opnd (N);
1373 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
1374 Ctyp : constant Entity_Id := Component_Type (Typ1);
1377 Func_Body : Node_Id;
1378 Func_Name : Entity_Id;
1382 Byte_Addressable : constant Boolean := System_Storage_Unit = Byte'Size;
1383 -- True for byte addressable target
1385 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean;
1386 -- Returns True if the length of the given operand is known to be less
1387 -- than 4. Returns False if this length is known to be four or greater
1388 -- or is not known at compile time.
1390 ------------------------
1391 -- Length_Less_Than_4 --
1392 ------------------------
1394 function Length_Less_Than_4 (Opnd : Node_Id) return Boolean is
1395 Otyp : constant Entity_Id := Etype (Opnd);
1398 if Ekind (Otyp) = E_String_Literal_Subtype then
1399 return String_Literal_Length (Otyp) < 4;
1403 Ityp : constant Entity_Id := Etype (First_Index (Otyp));
1404 Lo : constant Node_Id := Type_Low_Bound (Ityp);
1405 Hi : constant Node_Id := Type_High_Bound (Ityp);
1410 if Compile_Time_Known_Value (Lo) then
1411 Lov := Expr_Value (Lo);
1416 if Compile_Time_Known_Value (Hi) then
1417 Hiv := Expr_Value (Hi);
1422 return Hiv < Lov + 3;
1425 end Length_Less_Than_4;
1427 -- Start of processing for Expand_Array_Comparison
1430 -- Deal first with unpacked case, where we can call a runtime routine
1431 -- except that we avoid this for targets for which are not addressable
1432 -- by bytes, and for the JVM/CIL, since they do not support direct
1433 -- addressing of array components.
1435 if not Is_Bit_Packed_Array (Typ1)
1436 and then Byte_Addressable
1437 and then VM_Target = No_VM
1439 -- The call we generate is:
1441 -- Compare_Array_xn[_Unaligned]
1442 -- (left'address, right'address, left'length, right'length) <op> 0
1444 -- x = U for unsigned, S for signed
1445 -- n = 8,16,32,64 for component size
1446 -- Add _Unaligned if length < 4 and component size is 8.
1447 -- <op> is the standard comparison operator
1449 if Component_Size (Typ1) = 8 then
1450 if Length_Less_Than_4 (Op1)
1452 Length_Less_Than_4 (Op2)
1454 if Is_Unsigned_Type (Ctyp) then
1455 Comp := RE_Compare_Array_U8_Unaligned;
1457 Comp := RE_Compare_Array_S8_Unaligned;
1461 if Is_Unsigned_Type (Ctyp) then
1462 Comp := RE_Compare_Array_U8;
1464 Comp := RE_Compare_Array_S8;
1468 elsif Component_Size (Typ1) = 16 then
1469 if Is_Unsigned_Type (Ctyp) then
1470 Comp := RE_Compare_Array_U16;
1472 Comp := RE_Compare_Array_S16;
1475 elsif Component_Size (Typ1) = 32 then
1476 if Is_Unsigned_Type (Ctyp) then
1477 Comp := RE_Compare_Array_U32;
1479 Comp := RE_Compare_Array_S32;
1482 else pragma Assert (Component_Size (Typ1) = 64);
1483 if Is_Unsigned_Type (Ctyp) then
1484 Comp := RE_Compare_Array_U64;
1486 Comp := RE_Compare_Array_S64;
1490 Remove_Side_Effects (Op1, Name_Req => True);
1491 Remove_Side_Effects (Op2, Name_Req => True);
1494 Make_Function_Call (Sloc (Op1),
1495 Name => New_Occurrence_Of (RTE (Comp), Loc),
1497 Parameter_Associations => New_List (
1498 Make_Attribute_Reference (Loc,
1499 Prefix => Relocate_Node (Op1),
1500 Attribute_Name => Name_Address),
1502 Make_Attribute_Reference (Loc,
1503 Prefix => Relocate_Node (Op2),
1504 Attribute_Name => Name_Address),
1506 Make_Attribute_Reference (Loc,
1507 Prefix => Relocate_Node (Op1),
1508 Attribute_Name => Name_Length),
1510 Make_Attribute_Reference (Loc,
1511 Prefix => Relocate_Node (Op2),
1512 Attribute_Name => Name_Length))));
1515 Make_Integer_Literal (Sloc (Op2),
1518 Analyze_And_Resolve (Op1, Standard_Integer);
1519 Analyze_And_Resolve (Op2, Standard_Integer);
1523 -- Cases where we cannot make runtime call
1525 -- For (a <= b) we convert to not (a > b)
1527 if Chars (N) = Name_Op_Le then
1533 Right_Opnd => Op2)));
1534 Analyze_And_Resolve (N, Standard_Boolean);
1537 -- For < the Boolean expression is
1538 -- greater__nn (op2, op1)
1540 elsif Chars (N) = Name_Op_Lt then
1541 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1545 Op1 := Right_Opnd (N);
1546 Op2 := Left_Opnd (N);
1548 -- For (a >= b) we convert to not (a < b)
1550 elsif Chars (N) = Name_Op_Ge then
1556 Right_Opnd => Op2)));
1557 Analyze_And_Resolve (N, Standard_Boolean);
1560 -- For > the Boolean expression is
1561 -- greater__nn (op1, op2)
1564 pragma Assert (Chars (N) = Name_Op_Gt);
1565 Func_Body := Make_Array_Comparison_Op (Typ1, N);
1568 Func_Name := Defining_Unit_Name (Specification (Func_Body));
1570 Make_Function_Call (Loc,
1571 Name => New_Reference_To (Func_Name, Loc),
1572 Parameter_Associations => New_List (Op1, Op2));
1574 Insert_Action (N, Func_Body);
1576 Analyze_And_Resolve (N, Standard_Boolean);
1579 when RE_Not_Available =>
1581 end Expand_Array_Comparison;
1583 ---------------------------
1584 -- Expand_Array_Equality --
1585 ---------------------------
1587 -- Expand an equality function for multi-dimensional arrays. Here is an
1588 -- example of such a function for Nb_Dimension = 2
1590 -- function Enn (A : atyp; B : btyp) return boolean is
1592 -- if (A'length (1) = 0 or else A'length (2) = 0)
1594 -- (B'length (1) = 0 or else B'length (2) = 0)
1596 -- return True; -- RM 4.5.2(22)
1599 -- if A'length (1) /= B'length (1)
1601 -- A'length (2) /= B'length (2)
1603 -- return False; -- RM 4.5.2(23)
1607 -- A1 : Index_T1 := A'first (1);
1608 -- B1 : Index_T1 := B'first (1);
1612 -- A2 : Index_T2 := A'first (2);
1613 -- B2 : Index_T2 := B'first (2);
1616 -- if A (A1, A2) /= B (B1, B2) then
1620 -- exit when A2 = A'last (2);
1621 -- A2 := Index_T2'succ (A2);
1622 -- B2 := Index_T2'succ (B2);
1626 -- exit when A1 = A'last (1);
1627 -- A1 := Index_T1'succ (A1);
1628 -- B1 := Index_T1'succ (B1);
1635 -- Note on the formal types used (atyp and btyp). If either of the arrays
1636 -- is of a private type, we use the underlying type, and do an unchecked
1637 -- conversion of the actual. If either of the arrays has a bound depending
1638 -- on a discriminant, then we use the base type since otherwise we have an
1639 -- escaped discriminant in the function.
1641 -- If both arrays are constrained and have the same bounds, we can generate
1642 -- a loop with an explicit iteration scheme using a 'Range attribute over
1645 function Expand_Array_Equality
1650 Typ : Entity_Id) return Node_Id
1652 Loc : constant Source_Ptr := Sloc (Nod);
1653 Decls : constant List_Id := New_List;
1654 Index_List1 : constant List_Id := New_List;
1655 Index_List2 : constant List_Id := New_List;
1659 Func_Name : Entity_Id;
1660 Func_Body : Node_Id;
1662 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
1663 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
1667 -- The parameter types to be used for the formals
1672 Num : Int) return Node_Id;
1673 -- This builds the attribute reference Arr'Nam (Expr)
1675 function Component_Equality (Typ : Entity_Id) return Node_Id;
1676 -- Create one statement to compare corresponding components, designated
1677 -- by a full set of indexes.
1679 function Get_Arg_Type (N : Node_Id) return Entity_Id;
1680 -- Given one of the arguments, computes the appropriate type to be used
1681 -- for that argument in the corresponding function formal
1683 function Handle_One_Dimension
1685 Index : Node_Id) return Node_Id;
1686 -- This procedure returns the following code
1689 -- Bn : Index_T := B'First (N);
1693 -- exit when An = A'Last (N);
1694 -- An := Index_T'Succ (An)
1695 -- Bn := Index_T'Succ (Bn)
1699 -- If both indexes are constrained and identical, the procedure
1700 -- returns a simpler loop:
1702 -- for An in A'Range (N) loop
1706 -- N is the dimension for which we are generating a loop. Index is the
1707 -- N'th index node, whose Etype is Index_Type_n in the above code. The
1708 -- xxx statement is either the loop or declare for the next dimension
1709 -- or if this is the last dimension the comparison of corresponding
1710 -- components of the arrays.
1712 -- The actual way the code works is to return the comparison of
1713 -- corresponding components for the N+1 call. That's neater!
1715 function Test_Empty_Arrays return Node_Id;
1716 -- This function constructs the test for both arrays being empty
1717 -- (A'length (1) = 0 or else A'length (2) = 0 or else ...)
1719 -- (B'length (1) = 0 or else B'length (2) = 0 or else ...)
1721 function Test_Lengths_Correspond return Node_Id;
1722 -- This function constructs the test for arrays having different lengths
1723 -- in at least one index position, in which case the resulting code is:
1725 -- A'length (1) /= B'length (1)
1727 -- A'length (2) /= B'length (2)
1738 Num : Int) return Node_Id
1742 Make_Attribute_Reference (Loc,
1743 Attribute_Name => Nam,
1744 Prefix => New_Reference_To (Arr, Loc),
1745 Expressions => New_List (Make_Integer_Literal (Loc, Num)));
1748 ------------------------
1749 -- Component_Equality --
1750 ------------------------
1752 function Component_Equality (Typ : Entity_Id) return Node_Id is
1757 -- if a(i1...) /= b(j1...) then return false; end if;
1760 Make_Indexed_Component (Loc,
1761 Prefix => Make_Identifier (Loc, Chars (A)),
1762 Expressions => Index_List1);
1765 Make_Indexed_Component (Loc,
1766 Prefix => Make_Identifier (Loc, Chars (B)),
1767 Expressions => Index_List2);
1769 Test := Expand_Composite_Equality
1770 (Nod, Component_Type (Typ), L, R, Decls);
1772 -- If some (sub)component is an unchecked_union, the whole operation
1773 -- will raise program error.
1775 if Nkind (Test) = N_Raise_Program_Error then
1777 -- This node is going to be inserted at a location where a
1778 -- statement is expected: clear its Etype so analysis will set
1779 -- it to the expected Standard_Void_Type.
1781 Set_Etype (Test, Empty);
1786 Make_Implicit_If_Statement (Nod,
1787 Condition => Make_Op_Not (Loc, Right_Opnd => Test),
1788 Then_Statements => New_List (
1789 Make_Simple_Return_Statement (Loc,
1790 Expression => New_Occurrence_Of (Standard_False, Loc))));
1792 end Component_Equality;
1798 function Get_Arg_Type (N : Node_Id) return Entity_Id is
1809 T := Underlying_Type (T);
1811 X := First_Index (T);
1812 while Present (X) loop
1813 if Denotes_Discriminant (Type_Low_Bound (Etype (X)))
1815 Denotes_Discriminant (Type_High_Bound (Etype (X)))
1828 --------------------------
1829 -- Handle_One_Dimension --
1830 ---------------------------
1832 function Handle_One_Dimension
1834 Index : Node_Id) return Node_Id
1836 Need_Separate_Indexes : constant Boolean :=
1838 or else not Is_Constrained (Ltyp);
1839 -- If the index types are identical, and we are working with
1840 -- constrained types, then we can use the same index for both
1843 An : constant Entity_Id := Make_Temporary (Loc, 'A');
1846 Index_T : Entity_Id;
1851 if N > Number_Dimensions (Ltyp) then
1852 return Component_Equality (Ltyp);
1855 -- Case where we generate a loop
1857 Index_T := Base_Type (Etype (Index));
1859 if Need_Separate_Indexes then
1860 Bn := Make_Temporary (Loc, 'B');
1865 Append (New_Reference_To (An, Loc), Index_List1);
1866 Append (New_Reference_To (Bn, Loc), Index_List2);
1868 Stm_List := New_List (
1869 Handle_One_Dimension (N + 1, Next_Index (Index)));
1871 if Need_Separate_Indexes then
1873 -- Generate guard for loop, followed by increments of indexes
1875 Append_To (Stm_List,
1876 Make_Exit_Statement (Loc,
1879 Left_Opnd => New_Reference_To (An, Loc),
1880 Right_Opnd => Arr_Attr (A, Name_Last, N))));
1882 Append_To (Stm_List,
1883 Make_Assignment_Statement (Loc,
1884 Name => New_Reference_To (An, Loc),
1886 Make_Attribute_Reference (Loc,
1887 Prefix => New_Reference_To (Index_T, Loc),
1888 Attribute_Name => Name_Succ,
1889 Expressions => New_List (New_Reference_To (An, Loc)))));
1891 Append_To (Stm_List,
1892 Make_Assignment_Statement (Loc,
1893 Name => New_Reference_To (Bn, Loc),
1895 Make_Attribute_Reference (Loc,
1896 Prefix => New_Reference_To (Index_T, Loc),
1897 Attribute_Name => Name_Succ,
1898 Expressions => New_List (New_Reference_To (Bn, Loc)))));
1901 -- If separate indexes, we need a declare block for An and Bn, and a
1902 -- loop without an iteration scheme.
1904 if Need_Separate_Indexes then
1906 Make_Implicit_Loop_Statement (Nod, Statements => Stm_List);
1909 Make_Block_Statement (Loc,
1910 Declarations => New_List (
1911 Make_Object_Declaration (Loc,
1912 Defining_Identifier => An,
1913 Object_Definition => New_Reference_To (Index_T, Loc),
1914 Expression => Arr_Attr (A, Name_First, N)),
1916 Make_Object_Declaration (Loc,
1917 Defining_Identifier => Bn,
1918 Object_Definition => New_Reference_To (Index_T, Loc),
1919 Expression => Arr_Attr (B, Name_First, N))),
1921 Handled_Statement_Sequence =>
1922 Make_Handled_Sequence_Of_Statements (Loc,
1923 Statements => New_List (Loop_Stm)));
1925 -- If no separate indexes, return loop statement with explicit
1926 -- iteration scheme on its own
1930 Make_Implicit_Loop_Statement (Nod,
1931 Statements => Stm_List,
1933 Make_Iteration_Scheme (Loc,
1934 Loop_Parameter_Specification =>
1935 Make_Loop_Parameter_Specification (Loc,
1936 Defining_Identifier => An,
1937 Discrete_Subtype_Definition =>
1938 Arr_Attr (A, Name_Range, N))));
1941 end Handle_One_Dimension;
1943 -----------------------
1944 -- Test_Empty_Arrays --
1945 -----------------------
1947 function Test_Empty_Arrays return Node_Id is
1957 for J in 1 .. Number_Dimensions (Ltyp) loop
1960 Left_Opnd => Arr_Attr (A, Name_Length, J),
1961 Right_Opnd => Make_Integer_Literal (Loc, 0));
1965 Left_Opnd => Arr_Attr (B, Name_Length, J),
1966 Right_Opnd => Make_Integer_Literal (Loc, 0));
1975 Left_Opnd => Relocate_Node (Alist),
1976 Right_Opnd => Atest);
1980 Left_Opnd => Relocate_Node (Blist),
1981 Right_Opnd => Btest);
1988 Right_Opnd => Blist);
1989 end Test_Empty_Arrays;
1991 -----------------------------
1992 -- Test_Lengths_Correspond --
1993 -----------------------------
1995 function Test_Lengths_Correspond return Node_Id is
2001 for J in 1 .. Number_Dimensions (Ltyp) loop
2004 Left_Opnd => Arr_Attr (A, Name_Length, J),
2005 Right_Opnd => Arr_Attr (B, Name_Length, J));
2012 Left_Opnd => Relocate_Node (Result),
2013 Right_Opnd => Rtest);
2018 end Test_Lengths_Correspond;
2020 -- Start of processing for Expand_Array_Equality
2023 Ltyp := Get_Arg_Type (Lhs);
2024 Rtyp := Get_Arg_Type (Rhs);
2026 -- For now, if the argument types are not the same, go to the base type,
2027 -- since the code assumes that the formals have the same type. This is
2028 -- fixable in future ???
2030 if Ltyp /= Rtyp then
2031 Ltyp := Base_Type (Ltyp);
2032 Rtyp := Base_Type (Rtyp);
2033 pragma Assert (Ltyp = Rtyp);
2036 -- Build list of formals for function
2038 Formals := New_List (
2039 Make_Parameter_Specification (Loc,
2040 Defining_Identifier => A,
2041 Parameter_Type => New_Reference_To (Ltyp, Loc)),
2043 Make_Parameter_Specification (Loc,
2044 Defining_Identifier => B,
2045 Parameter_Type => New_Reference_To (Rtyp, Loc)));
2047 Func_Name := Make_Temporary (Loc, 'E');
2049 -- Build statement sequence for function
2052 Make_Subprogram_Body (Loc,
2054 Make_Function_Specification (Loc,
2055 Defining_Unit_Name => Func_Name,
2056 Parameter_Specifications => Formals,
2057 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
2059 Declarations => Decls,
2061 Handled_Statement_Sequence =>
2062 Make_Handled_Sequence_Of_Statements (Loc,
2063 Statements => New_List (
2065 Make_Implicit_If_Statement (Nod,
2066 Condition => Test_Empty_Arrays,
2067 Then_Statements => New_List (
2068 Make_Simple_Return_Statement (Loc,
2070 New_Occurrence_Of (Standard_True, Loc)))),
2072 Make_Implicit_If_Statement (Nod,
2073 Condition => Test_Lengths_Correspond,
2074 Then_Statements => New_List (
2075 Make_Simple_Return_Statement (Loc,
2077 New_Occurrence_Of (Standard_False, Loc)))),
2079 Handle_One_Dimension (1, First_Index (Ltyp)),
2081 Make_Simple_Return_Statement (Loc,
2082 Expression => New_Occurrence_Of (Standard_True, Loc)))));
2084 Set_Has_Completion (Func_Name, True);
2085 Set_Is_Inlined (Func_Name);
2087 -- If the array type is distinct from the type of the arguments, it
2088 -- is the full view of a private type. Apply an unchecked conversion
2089 -- to insure that analysis of the call succeeds.
2099 or else Base_Type (Etype (Lhs)) /= Base_Type (Ltyp)
2101 L := OK_Convert_To (Ltyp, Lhs);
2105 or else Base_Type (Etype (Rhs)) /= Base_Type (Rtyp)
2107 R := OK_Convert_To (Rtyp, Rhs);
2110 Actuals := New_List (L, R);
2113 Append_To (Bodies, Func_Body);
2116 Make_Function_Call (Loc,
2117 Name => New_Reference_To (Func_Name, Loc),
2118 Parameter_Associations => Actuals);
2119 end Expand_Array_Equality;
2121 -----------------------------
2122 -- Expand_Boolean_Operator --
2123 -----------------------------
2125 -- Note that we first get the actual subtypes of the operands, since we
2126 -- always want to deal with types that have bounds.
2128 procedure Expand_Boolean_Operator (N : Node_Id) is
2129 Typ : constant Entity_Id := Etype (N);
2132 -- Special case of bit packed array where both operands are known to be
2133 -- properly aligned. In this case we use an efficient run time routine
2134 -- to carry out the operation (see System.Bit_Ops).
2136 if Is_Bit_Packed_Array (Typ)
2137 and then not Is_Possibly_Unaligned_Object (Left_Opnd (N))
2138 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
2140 Expand_Packed_Boolean_Operator (N);
2144 -- For the normal non-packed case, the general expansion is to build
2145 -- function for carrying out the comparison (use Make_Boolean_Array_Op)
2146 -- and then inserting it into the tree. The original operator node is
2147 -- then rewritten as a call to this function. We also use this in the
2148 -- packed case if either operand is a possibly unaligned object.
2151 Loc : constant Source_Ptr := Sloc (N);
2152 L : constant Node_Id := Relocate_Node (Left_Opnd (N));
2153 R : constant Node_Id := Relocate_Node (Right_Opnd (N));
2154 Func_Body : Node_Id;
2155 Func_Name : Entity_Id;
2158 Convert_To_Actual_Subtype (L);
2159 Convert_To_Actual_Subtype (R);
2160 Ensure_Defined (Etype (L), N);
2161 Ensure_Defined (Etype (R), N);
2162 Apply_Length_Check (R, Etype (L));
2164 if Nkind (N) = N_Op_Xor then
2165 Silly_Boolean_Array_Xor_Test (N, Etype (L));
2168 if Nkind (Parent (N)) = N_Assignment_Statement
2169 and then Safe_In_Place_Array_Op (Name (Parent (N)), L, R)
2171 Build_Boolean_Array_Proc_Call (Parent (N), L, R);
2173 elsif Nkind (Parent (N)) = N_Op_Not
2174 and then Nkind (N) = N_Op_And
2176 Safe_In_Place_Array_Op (Name (Parent (Parent (N))), L, R)
2181 Func_Body := Make_Boolean_Array_Op (Etype (L), N);
2182 Func_Name := Defining_Unit_Name (Specification (Func_Body));
2183 Insert_Action (N, Func_Body);
2185 -- Now rewrite the expression with a call
2188 Make_Function_Call (Loc,
2189 Name => New_Reference_To (Func_Name, Loc),
2190 Parameter_Associations =>
2193 Make_Type_Conversion
2194 (Loc, New_Reference_To (Etype (L), Loc), R))));
2196 Analyze_And_Resolve (N, Typ);
2199 end Expand_Boolean_Operator;
2201 -------------------------------
2202 -- Expand_Composite_Equality --
2203 -------------------------------
2205 -- This function is only called for comparing internal fields of composite
2206 -- types when these fields are themselves composites. This is a special
2207 -- case because it is not possible to respect normal Ada visibility rules.
2209 function Expand_Composite_Equality
2214 Bodies : List_Id) return Node_Id
2216 Loc : constant Source_Ptr := Sloc (Nod);
2217 Full_Type : Entity_Id;
2221 function Find_Primitive_Eq return Node_Id;
2222 -- AI05-0123: Locate primitive equality for type if it exists, and
2223 -- build the corresponding call. If operation is abstract, replace
2224 -- call with an explicit raise. Return Empty if there is no primitive.
2226 -----------------------
2227 -- Find_Primitive_Eq --
2228 -----------------------
2230 function Find_Primitive_Eq return Node_Id is
2235 Prim_E := First_Elmt (Collect_Primitive_Operations (Typ));
2236 while Present (Prim_E) loop
2237 Prim := Node (Prim_E);
2239 -- Locate primitive equality with the right signature
2241 if Chars (Prim) = Name_Op_Eq
2242 and then Etype (First_Formal (Prim)) =
2243 Etype (Next_Formal (First_Formal (Prim)))
2244 and then Etype (Prim) = Standard_Boolean
2246 if Is_Abstract_Subprogram (Prim) then
2248 Make_Raise_Program_Error (Loc,
2249 Reason => PE_Explicit_Raise);
2253 Make_Function_Call (Loc,
2254 Name => New_Reference_To (Prim, Loc),
2255 Parameter_Associations => New_List (Lhs, Rhs));
2262 -- If not found, predefined operation will be used
2265 end Find_Primitive_Eq;
2267 -- Start of processing for Expand_Composite_Equality
2270 if Is_Private_Type (Typ) then
2271 Full_Type := Underlying_Type (Typ);
2276 -- Defense against malformed private types with no completion the error
2277 -- will be diagnosed later by check_completion
2279 if No (Full_Type) then
2280 return New_Reference_To (Standard_False, Loc);
2283 Full_Type := Base_Type (Full_Type);
2285 if Is_Array_Type (Full_Type) then
2287 -- If the operand is an elementary type other than a floating-point
2288 -- type, then we can simply use the built-in block bitwise equality,
2289 -- since the predefined equality operators always apply and bitwise
2290 -- equality is fine for all these cases.
2292 if Is_Elementary_Type (Component_Type (Full_Type))
2293 and then not Is_Floating_Point_Type (Component_Type (Full_Type))
2295 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2297 -- For composite component types, and floating-point types, use the
2298 -- expansion. This deals with tagged component types (where we use
2299 -- the applicable equality routine) and floating-point, (where we
2300 -- need to worry about negative zeroes), and also the case of any
2301 -- composite type recursively containing such fields.
2304 return Expand_Array_Equality (Nod, Lhs, Rhs, Bodies, Full_Type);
2307 elsif Is_Tagged_Type (Full_Type) then
2309 -- Call the primitive operation "=" of this type
2311 if Is_Class_Wide_Type (Full_Type) then
2312 Full_Type := Root_Type (Full_Type);
2315 -- If this is derived from an untagged private type completed with a
2316 -- tagged type, it does not have a full view, so we use the primitive
2317 -- operations of the private type. This check should no longer be
2318 -- necessary when these types receive their full views ???
2320 if Is_Private_Type (Typ)
2321 and then not Is_Tagged_Type (Typ)
2322 and then not Is_Controlled (Typ)
2323 and then Is_Derived_Type (Typ)
2324 and then No (Full_View (Typ))
2326 Prim := First_Elmt (Collect_Primitive_Operations (Typ));
2328 Prim := First_Elmt (Primitive_Operations (Full_Type));
2332 Eq_Op := Node (Prim);
2333 exit when Chars (Eq_Op) = Name_Op_Eq
2334 and then Etype (First_Formal (Eq_Op)) =
2335 Etype (Next_Formal (First_Formal (Eq_Op)))
2336 and then Base_Type (Etype (Eq_Op)) = Standard_Boolean;
2338 pragma Assert (Present (Prim));
2341 Eq_Op := Node (Prim);
2344 Make_Function_Call (Loc,
2345 Name => New_Reference_To (Eq_Op, Loc),
2346 Parameter_Associations =>
2348 (Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Lhs),
2349 Unchecked_Convert_To (Etype (First_Formal (Eq_Op)), Rhs)));
2351 elsif Is_Record_Type (Full_Type) then
2352 Eq_Op := TSS (Full_Type, TSS_Composite_Equality);
2354 if Present (Eq_Op) then
2355 if Etype (First_Formal (Eq_Op)) /= Full_Type then
2357 -- Inherited equality from parent type. Convert the actuals to
2358 -- match signature of operation.
2361 T : constant Entity_Id := Etype (First_Formal (Eq_Op));
2365 Make_Function_Call (Loc,
2366 Name => New_Reference_To (Eq_Op, Loc),
2367 Parameter_Associations => New_List (
2368 OK_Convert_To (T, Lhs),
2369 OK_Convert_To (T, Rhs)));
2373 -- Comparison between Unchecked_Union components
2375 if Is_Unchecked_Union (Full_Type) then
2377 Lhs_Type : Node_Id := Full_Type;
2378 Rhs_Type : Node_Id := Full_Type;
2379 Lhs_Discr_Val : Node_Id;
2380 Rhs_Discr_Val : Node_Id;
2385 if Nkind (Lhs) = N_Selected_Component then
2386 Lhs_Type := Etype (Entity (Selector_Name (Lhs)));
2391 if Nkind (Rhs) = N_Selected_Component then
2392 Rhs_Type := Etype (Entity (Selector_Name (Rhs)));
2395 -- Lhs of the composite equality
2397 if Is_Constrained (Lhs_Type) then
2399 -- Since the enclosing record type can never be an
2400 -- Unchecked_Union (this code is executed for records
2401 -- that do not have variants), we may reference its
2404 if Nkind (Lhs) = N_Selected_Component
2405 and then Has_Per_Object_Constraint (
2406 Entity (Selector_Name (Lhs)))
2409 Make_Selected_Component (Loc,
2410 Prefix => Prefix (Lhs),
2413 (Get_Discriminant_Value
2414 (First_Discriminant (Lhs_Type),
2416 Stored_Constraint (Lhs_Type))));
2421 (Get_Discriminant_Value
2422 (First_Discriminant (Lhs_Type),
2424 Stored_Constraint (Lhs_Type)));
2428 -- It is not possible to infer the discriminant since
2429 -- the subtype is not constrained.
2432 Make_Raise_Program_Error (Loc,
2433 Reason => PE_Unchecked_Union_Restriction);
2436 -- Rhs of the composite equality
2438 if Is_Constrained (Rhs_Type) then
2439 if Nkind (Rhs) = N_Selected_Component
2440 and then Has_Per_Object_Constraint
2441 (Entity (Selector_Name (Rhs)))
2444 Make_Selected_Component (Loc,
2445 Prefix => Prefix (Rhs),
2448 (Get_Discriminant_Value
2449 (First_Discriminant (Rhs_Type),
2451 Stored_Constraint (Rhs_Type))));
2456 (Get_Discriminant_Value
2457 (First_Discriminant (Rhs_Type),
2459 Stored_Constraint (Rhs_Type)));
2464 Make_Raise_Program_Error (Loc,
2465 Reason => PE_Unchecked_Union_Restriction);
2468 -- Call the TSS equality function with the inferred
2469 -- discriminant values.
2472 Make_Function_Call (Loc,
2473 Name => New_Reference_To (Eq_Op, Loc),
2474 Parameter_Associations => New_List (
2483 Make_Function_Call (Loc,
2484 Name => New_Reference_To (Eq_Op, Loc),
2485 Parameter_Associations => New_List (Lhs, Rhs));
2489 elsif Ada_Version >= Ada_2012 then
2491 -- if no TSS has been created for the type, check whether there is
2492 -- a primitive equality declared for it.
2495 Ada_2012_Op : constant Node_Id := Find_Primitive_Eq;
2498 if Present (Ada_2012_Op) then
2502 -- Use predefined equality if no user-defined primitive exists
2504 return Make_Op_Eq (Loc, Lhs, Rhs);
2509 return Expand_Record_Equality (Nod, Full_Type, Lhs, Rhs, Bodies);
2513 -- If not array or record type, it is predefined equality.
2515 return Make_Op_Eq (Loc, Left_Opnd => Lhs, Right_Opnd => Rhs);
2517 end Expand_Composite_Equality;
2519 ------------------------
2520 -- Expand_Concatenate --
2521 ------------------------
2523 procedure Expand_Concatenate (Cnode : Node_Id; Opnds : List_Id) is
2524 Loc : constant Source_Ptr := Sloc (Cnode);
2526 Atyp : constant Entity_Id := Base_Type (Etype (Cnode));
2527 -- Result type of concatenation
2529 Ctyp : constant Entity_Id := Base_Type (Component_Type (Etype (Cnode)));
2530 -- Component type. Elements of this component type can appear as one
2531 -- of the operands of concatenation as well as arrays.
2533 Istyp : constant Entity_Id := Etype (First_Index (Atyp));
2536 Ityp : constant Entity_Id := Base_Type (Istyp);
2537 -- Index type. This is the base type of the index subtype, and is used
2538 -- for all computed bounds (which may be out of range of Istyp in the
2539 -- case of null ranges).
2542 -- This is the type we use to do arithmetic to compute the bounds and
2543 -- lengths of operands. The choice of this type is a little subtle and
2544 -- is discussed in a separate section at the start of the body code.
2546 Concatenation_Error : exception;
2547 -- Raised if concatenation is sure to raise a CE
2549 Result_May_Be_Null : Boolean := True;
2550 -- Reset to False if at least one operand is encountered which is known
2551 -- at compile time to be non-null. Used for handling the special case
2552 -- of setting the high bound to the last operand high bound for a null
2553 -- result, thus ensuring a proper high bound in the super-flat case.
2555 N : constant Nat := List_Length (Opnds);
2556 -- Number of concatenation operands including possibly null operands
2559 -- Number of operands excluding any known to be null, except that the
2560 -- last operand is always retained, in case it provides the bounds for
2564 -- Current operand being processed in the loop through operands. After
2565 -- this loop is complete, always contains the last operand (which is not
2566 -- the same as Operands (NN), since null operands are skipped).
2568 -- Arrays describing the operands, only the first NN entries of each
2569 -- array are set (NN < N when we exclude known null operands).
2571 Is_Fixed_Length : array (1 .. N) of Boolean;
2572 -- True if length of corresponding operand known at compile time
2574 Operands : array (1 .. N) of Node_Id;
2575 -- Set to the corresponding entry in the Opnds list (but note that null
2576 -- operands are excluded, so not all entries in the list are stored).
2578 Fixed_Length : array (1 .. N) of Uint;
2579 -- Set to length of operand. Entries in this array are set only if the
2580 -- corresponding entry in Is_Fixed_Length is True.
2582 Opnd_Low_Bound : array (1 .. N) of Node_Id;
2583 -- Set to lower bound of operand. Either an integer literal in the case
2584 -- where the bound is known at compile time, else actual lower bound.
2585 -- The operand low bound is of type Ityp.
2587 Var_Length : array (1 .. N) of Entity_Id;
2588 -- Set to an entity of type Natural that contains the length of an
2589 -- operand whose length is not known at compile time. Entries in this
2590 -- array are set only if the corresponding entry in Is_Fixed_Length
2591 -- is False. The entity is of type Artyp.
2593 Aggr_Length : array (0 .. N) of Node_Id;
2594 -- The J'th entry in an expression node that represents the total length
2595 -- of operands 1 through J. It is either an integer literal node, or a
2596 -- reference to a constant entity with the right value, so it is fine
2597 -- to just do a Copy_Node to get an appropriate copy. The extra zero'th
2598 -- entry always is set to zero. The length is of type Artyp.
2600 Low_Bound : Node_Id;
2601 -- A tree node representing the low bound of the result (of type Ityp).
2602 -- This is either an integer literal node, or an identifier reference to
2603 -- a constant entity initialized to the appropriate value.
2605 Last_Opnd_High_Bound : Node_Id;
2606 -- A tree node representing the high bound of the last operand. This
2607 -- need only be set if the result could be null. It is used for the
2608 -- special case of setting the right high bound for a null result.
2609 -- This is of type Ityp.
2611 High_Bound : Node_Id;
2612 -- A tree node representing the high bound of the result (of type Ityp)
2615 -- Result of the concatenation (of type Ityp)
2617 Actions : constant List_Id := New_List;
2618 -- Collect actions to be inserted if Save_Space is False
2620 Save_Space : Boolean;
2621 pragma Warnings (Off, Save_Space);
2622 -- Set to True if we are saving generated code space by calling routines
2623 -- in packages System.Concat_n.
2625 Known_Non_Null_Operand_Seen : Boolean;
2626 -- Set True during generation of the assignments of operands into
2627 -- result once an operand known to be non-null has been seen.
2629 function Make_Artyp_Literal (Val : Nat) return Node_Id;
2630 -- This function makes an N_Integer_Literal node that is returned in
2631 -- analyzed form with the type set to Artyp. Importantly this literal
2632 -- is not flagged as static, so that if we do computations with it that
2633 -- result in statically detected out of range conditions, we will not
2634 -- generate error messages but instead warning messages.
2636 function To_Artyp (X : Node_Id) return Node_Id;
2637 -- Given a node of type Ityp, returns the corresponding value of type
2638 -- Artyp. For non-enumeration types, this is a plain integer conversion.
2639 -- For enum types, the Pos of the value is returned.
2641 function To_Ityp (X : Node_Id) return Node_Id;
2642 -- The inverse function (uses Val in the case of enumeration types)
2644 ------------------------
2645 -- Make_Artyp_Literal --
2646 ------------------------
2648 function Make_Artyp_Literal (Val : Nat) return Node_Id is
2649 Result : constant Node_Id := Make_Integer_Literal (Loc, Val);
2651 Set_Etype (Result, Artyp);
2652 Set_Analyzed (Result, True);
2653 Set_Is_Static_Expression (Result, False);
2655 end Make_Artyp_Literal;
2661 function To_Artyp (X : Node_Id) return Node_Id is
2663 if Ityp = Base_Type (Artyp) then
2666 elsif Is_Enumeration_Type (Ityp) then
2668 Make_Attribute_Reference (Loc,
2669 Prefix => New_Occurrence_Of (Ityp, Loc),
2670 Attribute_Name => Name_Pos,
2671 Expressions => New_List (X));
2674 return Convert_To (Artyp, X);
2682 function To_Ityp (X : Node_Id) return Node_Id is
2684 if Is_Enumeration_Type (Ityp) then
2686 Make_Attribute_Reference (Loc,
2687 Prefix => New_Occurrence_Of (Ityp, Loc),
2688 Attribute_Name => Name_Val,
2689 Expressions => New_List (X));
2691 -- Case where we will do a type conversion
2694 if Ityp = Base_Type (Artyp) then
2697 return Convert_To (Ityp, X);
2702 -- Local Declarations
2704 Opnd_Typ : Entity_Id;
2711 -- Start of processing for Expand_Concatenate
2714 -- Choose an appropriate computational type
2716 -- We will be doing calculations of lengths and bounds in this routine
2717 -- and computing one from the other in some cases, e.g. getting the high
2718 -- bound by adding the length-1 to the low bound.
2720 -- We can't just use the index type, or even its base type for this
2721 -- purpose for two reasons. First it might be an enumeration type which
2722 -- is not suitable for computations of any kind, and second it may
2723 -- simply not have enough range. For example if the index type is
2724 -- -128..+127 then lengths can be up to 256, which is out of range of
2727 -- For enumeration types, we can simply use Standard_Integer, this is
2728 -- sufficient since the actual number of enumeration literals cannot
2729 -- possibly exceed the range of integer (remember we will be doing the
2730 -- arithmetic with POS values, not representation values).
2732 if Is_Enumeration_Type (Ityp) then
2733 Artyp := Standard_Integer;
2735 -- If index type is Positive, we use the standard unsigned type, to give
2736 -- more room on the top of the range, obviating the need for an overflow
2737 -- check when creating the upper bound. This is needed to avoid junk
2738 -- overflow checks in the common case of String types.
2740 -- ??? Disabled for now
2742 -- elsif Istyp = Standard_Positive then
2743 -- Artyp := Standard_Unsigned;
2745 -- For modular types, we use a 32-bit modular type for types whose size
2746 -- is in the range 1-31 bits. For 32-bit unsigned types, we use the
2747 -- identity type, and for larger unsigned types we use 64-bits.
2749 elsif Is_Modular_Integer_Type (Ityp) then
2750 if RM_Size (Ityp) < RM_Size (Standard_Unsigned) then
2751 Artyp := Standard_Unsigned;
2752 elsif RM_Size (Ityp) = RM_Size (Standard_Unsigned) then
2755 Artyp := RTE (RE_Long_Long_Unsigned);
2758 -- Similar treatment for signed types
2761 if RM_Size (Ityp) < RM_Size (Standard_Integer) then
2762 Artyp := Standard_Integer;
2763 elsif RM_Size (Ityp) = RM_Size (Standard_Integer) then
2766 Artyp := Standard_Long_Long_Integer;
2770 -- Supply dummy entry at start of length array
2772 Aggr_Length (0) := Make_Artyp_Literal (0);
2774 -- Go through operands setting up the above arrays
2778 Opnd := Remove_Head (Opnds);
2779 Opnd_Typ := Etype (Opnd);
2781 -- The parent got messed up when we put the operands in a list,
2782 -- so now put back the proper parent for the saved operand, that
2783 -- is to say the concatenation node, to make sure that each operand
2784 -- is seen as a subexpression, e.g. if actions must be inserted.
2786 Set_Parent (Opnd, Cnode);
2788 -- Set will be True when we have setup one entry in the array
2792 -- Singleton element (or character literal) case
2794 if Base_Type (Opnd_Typ) = Ctyp then
2796 Operands (NN) := Opnd;
2797 Is_Fixed_Length (NN) := True;
2798 Fixed_Length (NN) := Uint_1;
2799 Result_May_Be_Null := False;
2801 -- Set low bound of operand (no need to set Last_Opnd_High_Bound
2802 -- since we know that the result cannot be null).
2804 Opnd_Low_Bound (NN) :=
2805 Make_Attribute_Reference (Loc,
2806 Prefix => New_Reference_To (Istyp, Loc),
2807 Attribute_Name => Name_First);
2811 -- String literal case (can only occur for strings of course)
2813 elsif Nkind (Opnd) = N_String_Literal then
2814 Len := String_Literal_Length (Opnd_Typ);
2817 Result_May_Be_Null := False;
2820 -- Capture last operand high bound if result could be null
2822 if J = N and then Result_May_Be_Null then
2823 Last_Opnd_High_Bound :=
2826 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ)),
2827 Right_Opnd => Make_Integer_Literal (Loc, 1));
2830 -- Skip null string literal
2832 if J < N and then Len = 0 then
2837 Operands (NN) := Opnd;
2838 Is_Fixed_Length (NN) := True;
2840 -- Set length and bounds
2842 Fixed_Length (NN) := Len;
2844 Opnd_Low_Bound (NN) :=
2845 New_Copy_Tree (String_Literal_Low_Bound (Opnd_Typ));
2852 -- Check constrained case with known bounds
2854 if Is_Constrained (Opnd_Typ) then
2856 Index : constant Node_Id := First_Index (Opnd_Typ);
2857 Indx_Typ : constant Entity_Id := Etype (Index);
2858 Lo : constant Node_Id := Type_Low_Bound (Indx_Typ);
2859 Hi : constant Node_Id := Type_High_Bound (Indx_Typ);
2862 -- Fixed length constrained array type with known at compile
2863 -- time bounds is last case of fixed length operand.
2865 if Compile_Time_Known_Value (Lo)
2867 Compile_Time_Known_Value (Hi)
2870 Loval : constant Uint := Expr_Value (Lo);
2871 Hival : constant Uint := Expr_Value (Hi);
2872 Len : constant Uint :=
2873 UI_Max (Hival - Loval + 1, Uint_0);
2877 Result_May_Be_Null := False;
2880 -- Capture last operand bound if result could be null
2882 if J = N and then Result_May_Be_Null then
2883 Last_Opnd_High_Bound :=
2885 Make_Integer_Literal (Loc, Expr_Value (Hi)));
2888 -- Exclude null length case unless last operand
2890 if J < N and then Len = 0 then
2895 Operands (NN) := Opnd;
2896 Is_Fixed_Length (NN) := True;
2897 Fixed_Length (NN) := Len;
2899 Opnd_Low_Bound (NN) :=
2901 (Make_Integer_Literal (Loc, Expr_Value (Lo)));
2908 -- All cases where the length is not known at compile time, or the
2909 -- special case of an operand which is known to be null but has a
2910 -- lower bound other than 1 or is other than a string type.
2915 -- Capture operand bounds
2917 Opnd_Low_Bound (NN) :=
2918 Make_Attribute_Reference (Loc,
2920 Duplicate_Subexpr (Opnd, Name_Req => True),
2921 Attribute_Name => Name_First);
2923 if J = N and Result_May_Be_Null then
2924 Last_Opnd_High_Bound :=
2926 Make_Attribute_Reference (Loc,
2928 Duplicate_Subexpr (Opnd, Name_Req => True),
2929 Attribute_Name => Name_Last));
2932 -- Capture length of operand in entity
2934 Operands (NN) := Opnd;
2935 Is_Fixed_Length (NN) := False;
2937 Var_Length (NN) := Make_Temporary (Loc, 'L');
2940 Make_Object_Declaration (Loc,
2941 Defining_Identifier => Var_Length (NN),
2942 Constant_Present => True,
2943 Object_Definition => New_Occurrence_Of (Artyp, Loc),
2945 Make_Attribute_Reference (Loc,
2947 Duplicate_Subexpr (Opnd, Name_Req => True),
2948 Attribute_Name => Name_Length)));
2952 -- Set next entry in aggregate length array
2954 -- For first entry, make either integer literal for fixed length
2955 -- or a reference to the saved length for variable length.
2958 if Is_Fixed_Length (1) then
2959 Aggr_Length (1) := Make_Integer_Literal (Loc, Fixed_Length (1));
2961 Aggr_Length (1) := New_Reference_To (Var_Length (1), Loc);
2964 -- If entry is fixed length and only fixed lengths so far, make
2965 -- appropriate new integer literal adding new length.
2967 elsif Is_Fixed_Length (NN)
2968 and then Nkind (Aggr_Length (NN - 1)) = N_Integer_Literal
2971 Make_Integer_Literal (Loc,
2972 Intval => Fixed_Length (NN) + Intval (Aggr_Length (NN - 1)));
2974 -- All other cases, construct an addition node for the length and
2975 -- create an entity initialized to this length.
2978 Ent := Make_Temporary (Loc, 'L');
2980 if Is_Fixed_Length (NN) then
2981 Clen := Make_Integer_Literal (Loc, Fixed_Length (NN));
2983 Clen := New_Reference_To (Var_Length (NN), Loc);
2987 Make_Object_Declaration (Loc,
2988 Defining_Identifier => Ent,
2989 Constant_Present => True,
2990 Object_Definition => New_Occurrence_Of (Artyp, Loc),
2993 Left_Opnd => New_Copy (Aggr_Length (NN - 1)),
2994 Right_Opnd => Clen)));
2996 Aggr_Length (NN) := Make_Identifier (Loc, Chars => Chars (Ent));
3003 -- If we have only skipped null operands, return the last operand
3010 -- If we have only one non-null operand, return it and we are done.
3011 -- There is one case in which this cannot be done, and that is when
3012 -- the sole operand is of the element type, in which case it must be
3013 -- converted to an array, and the easiest way of doing that is to go
3014 -- through the normal general circuit.
3017 and then Base_Type (Etype (Operands (1))) /= Ctyp
3019 Result := Operands (1);
3023 -- Cases where we have a real concatenation
3025 -- Next step is to find the low bound for the result array that we
3026 -- will allocate. The rules for this are in (RM 4.5.6(5-7)).
3028 -- If the ultimate ancestor of the index subtype is a constrained array
3029 -- definition, then the lower bound is that of the index subtype as
3030 -- specified by (RM 4.5.3(6)).
3032 -- The right test here is to go to the root type, and then the ultimate
3033 -- ancestor is the first subtype of this root type.
3035 if Is_Constrained (First_Subtype (Root_Type (Atyp))) then
3037 Make_Attribute_Reference (Loc,
3039 New_Occurrence_Of (First_Subtype (Root_Type (Atyp)), Loc),
3040 Attribute_Name => Name_First);
3042 -- If the first operand in the list has known length we know that
3043 -- the lower bound of the result is the lower bound of this operand.
3045 elsif Is_Fixed_Length (1) then
3046 Low_Bound := Opnd_Low_Bound (1);
3048 -- OK, we don't know the lower bound, we have to build a horrible
3049 -- expression actions node of the form
3051 -- if Cond1'Length /= 0 then
3054 -- if Opnd2'Length /= 0 then
3059 -- The nesting ends either when we hit an operand whose length is known
3060 -- at compile time, or on reaching the last operand, whose low bound we
3061 -- take unconditionally whether or not it is null. It's easiest to do
3062 -- this with a recursive procedure:
3066 function Get_Known_Bound (J : Nat) return Node_Id;
3067 -- Returns the lower bound determined by operands J .. NN
3069 ---------------------
3070 -- Get_Known_Bound --
3071 ---------------------
3073 function Get_Known_Bound (J : Nat) return Node_Id is
3075 if Is_Fixed_Length (J) or else J = NN then
3076 return New_Copy (Opnd_Low_Bound (J));
3080 Make_Conditional_Expression (Loc,
3081 Expressions => New_List (
3084 Left_Opnd => New_Reference_To (Var_Length (J), Loc),
3085 Right_Opnd => Make_Integer_Literal (Loc, 0)),
3087 New_Copy (Opnd_Low_Bound (J)),
3088 Get_Known_Bound (J + 1)));
3090 end Get_Known_Bound;
3093 Ent := Make_Temporary (Loc, 'L');
3096 Make_Object_Declaration (Loc,
3097 Defining_Identifier => Ent,
3098 Constant_Present => True,
3099 Object_Definition => New_Occurrence_Of (Ityp, Loc),
3100 Expression => Get_Known_Bound (1)));
3102 Low_Bound := New_Reference_To (Ent, Loc);
3106 -- Now we can safely compute the upper bound, normally
3107 -- Low_Bound + Length - 1.
3112 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
3114 Make_Op_Subtract (Loc,
3115 Left_Opnd => New_Copy (Aggr_Length (NN)),
3116 Right_Opnd => Make_Artyp_Literal (1))));
3118 -- Note that calculation of the high bound may cause overflow in some
3119 -- very weird cases, so in the general case we need an overflow check on
3120 -- the high bound. We can avoid this for the common case of string types
3121 -- and other types whose index is Positive, since we chose a wider range
3122 -- for the arithmetic type.
3124 if Istyp /= Standard_Positive then
3125 Activate_Overflow_Check (High_Bound);
3128 -- Handle the exceptional case where the result is null, in which case
3129 -- case the bounds come from the last operand (so that we get the proper
3130 -- bounds if the last operand is super-flat).
3132 if Result_May_Be_Null then
3134 Make_Conditional_Expression (Loc,
3135 Expressions => New_List (
3137 Left_Opnd => New_Copy (Aggr_Length (NN)),
3138 Right_Opnd => Make_Artyp_Literal (0)),
3139 Last_Opnd_High_Bound,
3143 -- Here is where we insert the saved up actions
3145 Insert_Actions (Cnode, Actions, Suppress => All_Checks);
3147 -- Now we construct an array object with appropriate bounds. We mark
3148 -- the target as internal to prevent useless initialization when
3149 -- Initialize_Scalars is enabled. Also since this is the actual result
3150 -- entity, we make sure we have debug information for the result.
3152 Ent := Make_Temporary (Loc, 'S');
3153 Set_Is_Internal (Ent);
3154 Set_Needs_Debug_Info (Ent);
3156 -- If the bound is statically known to be out of range, we do not want
3157 -- to abort, we want a warning and a runtime constraint error. Note that
3158 -- we have arranged that the result will not be treated as a static
3159 -- constant, so we won't get an illegality during this insertion.
3161 Insert_Action (Cnode,
3162 Make_Object_Declaration (Loc,
3163 Defining_Identifier => Ent,
3164 Object_Definition =>
3165 Make_Subtype_Indication (Loc,
3166 Subtype_Mark => New_Occurrence_Of (Atyp, Loc),
3168 Make_Index_Or_Discriminant_Constraint (Loc,
3169 Constraints => New_List (
3171 Low_Bound => Low_Bound,
3172 High_Bound => High_Bound))))),
3173 Suppress => All_Checks);
3175 -- If the result of the concatenation appears as the initializing
3176 -- expression of an object declaration, we can just rename the
3177 -- result, rather than copying it.
3179 Set_OK_To_Rename (Ent);
3181 -- Catch the static out of range case now
3183 if Raises_Constraint_Error (High_Bound) then
3184 raise Concatenation_Error;
3187 -- Now we will generate the assignments to do the actual concatenation
3189 -- There is one case in which we will not do this, namely when all the
3190 -- following conditions are met:
3192 -- The result type is Standard.String
3194 -- There are nine or fewer retained (non-null) operands
3196 -- The optimization level is -O0
3198 -- The corresponding System.Concat_n.Str_Concat_n routine is
3199 -- available in the run time.
3201 -- The debug flag gnatd.c is not set
3203 -- If all these conditions are met then we generate a call to the
3204 -- relevant concatenation routine. The purpose of this is to avoid
3205 -- undesirable code bloat at -O0.
3207 if Atyp = Standard_String
3208 and then NN in 2 .. 9
3209 and then (Opt.Optimization_Level = 0 or else Debug_Flag_Dot_CC)
3210 and then not Debug_Flag_Dot_C
3213 RR : constant array (Nat range 2 .. 9) of RE_Id :=
3224 if RTE_Available (RR (NN)) then
3226 Opnds : constant List_Id :=
3227 New_List (New_Occurrence_Of (Ent, Loc));
3230 for J in 1 .. NN loop
3231 if Is_List_Member (Operands (J)) then
3232 Remove (Operands (J));
3235 if Base_Type (Etype (Operands (J))) = Ctyp then
3237 Make_Aggregate (Loc,
3238 Component_Associations => New_List (
3239 Make_Component_Association (Loc,
3240 Choices => New_List (
3241 Make_Integer_Literal (Loc, 1)),
3242 Expression => Operands (J)))));
3245 Append_To (Opnds, Operands (J));
3249 Insert_Action (Cnode,
3250 Make_Procedure_Call_Statement (Loc,
3251 Name => New_Reference_To (RTE (RR (NN)), Loc),
3252 Parameter_Associations => Opnds));
3254 Result := New_Reference_To (Ent, Loc);
3261 -- Not special case so generate the assignments
3263 Known_Non_Null_Operand_Seen := False;
3265 for J in 1 .. NN loop
3267 Lo : constant Node_Id :=
3269 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
3270 Right_Opnd => Aggr_Length (J - 1));
3272 Hi : constant Node_Id :=
3274 Left_Opnd => To_Artyp (New_Copy (Low_Bound)),
3276 Make_Op_Subtract (Loc,
3277 Left_Opnd => Aggr_Length (J),
3278 Right_Opnd => Make_Artyp_Literal (1)));
3281 -- Singleton case, simple assignment
3283 if Base_Type (Etype (Operands (J))) = Ctyp then
3284 Known_Non_Null_Operand_Seen := True;
3285 Insert_Action (Cnode,
3286 Make_Assignment_Statement (Loc,
3288 Make_Indexed_Component (Loc,
3289 Prefix => New_Occurrence_Of (Ent, Loc),
3290 Expressions => New_List (To_Ityp (Lo))),
3291 Expression => Operands (J)),
3292 Suppress => All_Checks);
3294 -- Array case, slice assignment, skipped when argument is fixed
3295 -- length and known to be null.
3297 elsif (not Is_Fixed_Length (J)) or else (Fixed_Length (J) > 0) then
3300 Make_Assignment_Statement (Loc,
3304 New_Occurrence_Of (Ent, Loc),
3307 Low_Bound => To_Ityp (Lo),
3308 High_Bound => To_Ityp (Hi))),
3309 Expression => Operands (J));
3311 if Is_Fixed_Length (J) then
3312 Known_Non_Null_Operand_Seen := True;
3314 elsif not Known_Non_Null_Operand_Seen then
3316 -- Here if operand length is not statically known and no
3317 -- operand known to be non-null has been processed yet.
3318 -- If operand length is 0, we do not need to perform the
3319 -- assignment, and we must avoid the evaluation of the
3320 -- high bound of the slice, since it may underflow if the
3321 -- low bound is Ityp'First.
3324 Make_Implicit_If_Statement (Cnode,
3328 New_Occurrence_Of (Var_Length (J), Loc),
3329 Right_Opnd => Make_Integer_Literal (Loc, 0)),
3330 Then_Statements => New_List (Assign));
3333 Insert_Action (Cnode, Assign, Suppress => All_Checks);
3339 -- Finally we build the result, which is a reference to the array object
3341 Result := New_Reference_To (Ent, Loc);
3344 Rewrite (Cnode, Result);
3345 Analyze_And_Resolve (Cnode, Atyp);
3348 when Concatenation_Error =>
3350 -- Kill warning generated for the declaration of the static out of
3351 -- range high bound, and instead generate a Constraint_Error with
3352 -- an appropriate specific message.
3354 Kill_Dead_Code (Declaration_Node (Entity (High_Bound)));
3355 Apply_Compile_Time_Constraint_Error
3357 Msg => "concatenation result upper bound out of range?",
3358 Reason => CE_Range_Check_Failed);
3359 -- Set_Etype (Cnode, Atyp);
3360 end Expand_Concatenate;
3362 ------------------------
3363 -- Expand_N_Allocator --
3364 ------------------------
3366 procedure Expand_N_Allocator (N : Node_Id) is
3367 PtrT : constant Entity_Id := Etype (N);
3368 Dtyp : constant Entity_Id := Available_View (Designated_Type (PtrT));
3369 Etyp : constant Entity_Id := Etype (Expression (N));
3370 Loc : constant Source_Ptr := Sloc (N);
3376 procedure Rewrite_Coextension (N : Node_Id);
3377 -- Static coextensions have the same lifetime as the entity they
3378 -- constrain. Such occurrences can be rewritten as aliased objects
3379 -- and their unrestricted access used instead of the coextension.
3381 function Size_In_Storage_Elements (E : Entity_Id) return Node_Id;
3382 -- Given a constrained array type E, returns a node representing the
3383 -- code to compute the size in storage elements for the given type.
3384 -- This is done without using the attribute (which malfunctions for
3387 -------------------------
3388 -- Rewrite_Coextension --
3389 -------------------------
3391 procedure Rewrite_Coextension (N : Node_Id) is
3392 Temp_Id : constant Node_Id := Make_Temporary (Loc, 'C');
3393 Temp_Decl : Node_Id;
3394 Insert_Nod : Node_Id;
3398 -- Cnn : aliased Etyp;
3401 Make_Object_Declaration (Loc,
3402 Defining_Identifier => Temp_Id,
3403 Aliased_Present => True,
3404 Object_Definition => New_Occurrence_Of (Etyp, Loc));
3406 if Nkind (Expression (N)) = N_Qualified_Expression then
3407 Set_Expression (Temp_Decl, Expression (Expression (N)));
3410 -- Find the proper insertion node for the declaration
3412 Insert_Nod := Parent (N);
3413 while Present (Insert_Nod) loop
3415 Nkind (Insert_Nod) in N_Statement_Other_Than_Procedure_Call
3416 or else Nkind (Insert_Nod) = N_Procedure_Call_Statement
3417 or else Nkind (Insert_Nod) in N_Declaration;
3419 Insert_Nod := Parent (Insert_Nod);
3422 Insert_Before (Insert_Nod, Temp_Decl);
3423 Analyze (Temp_Decl);
3426 Make_Attribute_Reference (Loc,
3427 Prefix => New_Occurrence_Of (Temp_Id, Loc),
3428 Attribute_Name => Name_Unrestricted_Access));
3430 Analyze_And_Resolve (N, PtrT);
3431 end Rewrite_Coextension;
3433 ------------------------------
3434 -- Size_In_Storage_Elements --
3435 ------------------------------
3437 function Size_In_Storage_Elements (E : Entity_Id) return Node_Id is
3439 -- Logically this just returns E'Max_Size_In_Storage_Elements.
3440 -- However, the reason for the existence of this function is
3441 -- to construct a test for sizes too large, which means near the
3442 -- 32-bit limit on a 32-bit machine, and precisely the trouble
3443 -- is that we get overflows when sizes are greater than 2**31.
3445 -- So what we end up doing for array types is to use the expression:
3447 -- number-of-elements * component_type'Max_Size_In_Storage_Elements
3449 -- which avoids this problem. All this is a bit bogus, but it does
3450 -- mean we catch common cases of trying to allocate arrays that
3451 -- are too large, and which in the absence of a check results in
3452 -- undetected chaos ???
3459 for J in 1 .. Number_Dimensions (E) loop
3461 Make_Attribute_Reference (Loc,
3462 Prefix => New_Occurrence_Of (E, Loc),
3463 Attribute_Name => Name_Length,
3464 Expressions => New_List (Make_Integer_Literal (Loc, J)));
3471 Make_Op_Multiply (Loc,
3478 Make_Op_Multiply (Loc,
3481 Make_Attribute_Reference (Loc,
3482 Prefix => New_Occurrence_Of (Component_Type (E), Loc),
3483 Attribute_Name => Name_Max_Size_In_Storage_Elements));
3485 end Size_In_Storage_Elements;
3487 -- Start of processing for Expand_N_Allocator
3490 -- RM E.2.3(22). We enforce that the expected type of an allocator
3491 -- shall not be a remote access-to-class-wide-limited-private type
3493 -- Why is this being done at expansion time, seems clearly wrong ???
3495 Validate_Remote_Access_To_Class_Wide_Type (N);
3497 -- Processing for anonymous access-to-controlled types. These access
3498 -- types receive a special finalization master which appears in the
3499 -- declarations of the enclosing semantic unit. This expansion is done
3500 -- now to ensure that any additional types generated by this routine
3501 -- or Expand_Allocator_Expression inherit the proper type attributes.
3503 if Ekind (PtrT) = E_Anonymous_Access_Type
3504 and then Needs_Finalization (Dtyp)
3506 -- Anonymous access-to-controlled types allocate on the global pool.
3507 -- Do not set this attribute on .NET/JVM since those targets do not
3510 if No (Associated_Storage_Pool (PtrT))
3511 and then VM_Target = No_VM
3513 Set_Associated_Storage_Pool
3514 (PtrT, Get_Global_Pool_For_Access_Type (PtrT));
3517 -- The finalization master must be inserted and analyzed as part of
3518 -- the current semantic unit. This form of expansion is not carried
3519 -- out in Alfa mode because it is useless.
3521 if No (Finalization_Master (PtrT))
3522 and then not Alfa_Mode
3524 Set_Finalization_Master (PtrT, Current_Anonymous_Master);
3528 -- Set the storage pool and find the appropriate version of Allocate to
3531 Pool := Associated_Storage_Pool (Root_Type (PtrT));
3532 Set_Storage_Pool (N, Pool);
3534 if Present (Pool) then
3535 if Is_RTE (Pool, RE_SS_Pool) then
3536 if VM_Target = No_VM then
3537 Set_Procedure_To_Call (N, RTE (RE_SS_Allocate));
3540 elsif Is_Class_Wide_Type (Etype (Pool)) then
3541 Set_Procedure_To_Call (N, RTE (RE_Allocate_Any));
3544 Set_Procedure_To_Call (N,
3545 Find_Prim_Op (Etype (Pool), Name_Allocate));
3549 -- Under certain circumstances we can replace an allocator by an access
3550 -- to statically allocated storage. The conditions, as noted in AARM
3551 -- 3.10 (10c) are as follows:
3553 -- Size and initial value is known at compile time
3554 -- Access type is access-to-constant
3556 -- The allocator is not part of a constraint on a record component,
3557 -- because in that case the inserted actions are delayed until the
3558 -- record declaration is fully analyzed, which is too late for the
3559 -- analysis of the rewritten allocator.
3561 if Is_Access_Constant (PtrT)
3562 and then Nkind (Expression (N)) = N_Qualified_Expression
3563 and then Compile_Time_Known_Value (Expression (Expression (N)))
3564 and then Size_Known_At_Compile_Time
3565 (Etype (Expression (Expression (N))))
3566 and then not Is_Record_Type (Current_Scope)
3568 -- Here we can do the optimization. For the allocator
3572 -- We insert an object declaration
3574 -- Tnn : aliased x := y;
3576 -- and replace the allocator by Tnn'Unrestricted_Access. Tnn is
3577 -- marked as requiring static allocation.
3579 Temp := Make_Temporary (Loc, 'T', Expression (Expression (N)));
3580 Desig := Subtype_Mark (Expression (N));
3582 -- If context is constrained, use constrained subtype directly,
3583 -- so that the constant is not labelled as having a nominally
3584 -- unconstrained subtype.
3586 if Entity (Desig) = Base_Type (Dtyp) then
3587 Desig := New_Occurrence_Of (Dtyp, Loc);
3591 Make_Object_Declaration (Loc,
3592 Defining_Identifier => Temp,
3593 Aliased_Present => True,
3594 Constant_Present => Is_Access_Constant (PtrT),
3595 Object_Definition => Desig,
3596 Expression => Expression (Expression (N))));
3599 Make_Attribute_Reference (Loc,
3600 Prefix => New_Occurrence_Of (Temp, Loc),
3601 Attribute_Name => Name_Unrestricted_Access));
3603 Analyze_And_Resolve (N, PtrT);
3605 -- We set the variable as statically allocated, since we don't want
3606 -- it going on the stack of the current procedure!
3608 Set_Is_Statically_Allocated (Temp);
3612 -- Same if the allocator is an access discriminant for a local object:
3613 -- instead of an allocator we create a local value and constrain the
3614 -- enclosing object with the corresponding access attribute.
3616 if Is_Static_Coextension (N) then
3617 Rewrite_Coextension (N);
3621 -- Check for size too large, we do this because the back end misses
3622 -- proper checks here and can generate rubbish allocation calls when
3623 -- we are near the limit. We only do this for the 32-bit address case
3624 -- since that is from a practical point of view where we see a problem.
3626 if System_Address_Size = 32
3627 and then not Storage_Checks_Suppressed (PtrT)
3628 and then not Storage_Checks_Suppressed (Dtyp)
3629 and then not Storage_Checks_Suppressed (Etyp)
3631 -- The check we want to generate should look like
3633 -- if Etyp'Max_Size_In_Storage_Elements > 3.5 gigabytes then
3634 -- raise Storage_Error;
3637 -- where 3.5 gigabytes is a constant large enough to accommodate any
3638 -- reasonable request for. But we can't do it this way because at
3639 -- least at the moment we don't compute this attribute right, and
3640 -- can silently give wrong results when the result gets large. Since
3641 -- this is all about large results, that's bad, so instead we only
3642 -- apply the check for constrained arrays, and manually compute the
3643 -- value of the attribute ???
3645 if Is_Array_Type (Etyp) and then Is_Constrained (Etyp) then
3647 Make_Raise_Storage_Error (Loc,
3650 Left_Opnd => Size_In_Storage_Elements (Etyp),
3652 Make_Integer_Literal (Loc, Uint_7 * (Uint_2 ** 29))),
3653 Reason => SE_Object_Too_Large));
3657 -- Handle case of qualified expression (other than optimization above)
3658 -- First apply constraint checks, because the bounds or discriminants
3659 -- in the aggregate might not match the subtype mark in the allocator.
3661 if Nkind (Expression (N)) = N_Qualified_Expression then
3662 Apply_Constraint_Check
3663 (Expression (Expression (N)), Etype (Expression (N)));
3665 Expand_Allocator_Expression (N);
3669 -- If the allocator is for a type which requires initialization, and
3670 -- there is no initial value (i.e. operand is a subtype indication
3671 -- rather than a qualified expression), then we must generate a call to
3672 -- the initialization routine using an expressions action node:
3674 -- [Pnnn : constant ptr_T := new (T); Init (Pnnn.all,...); Pnnn]
3676 -- Here ptr_T is the pointer type for the allocator, and T is the
3677 -- subtype of the allocator. A special case arises if the designated
3678 -- type of the access type is a task or contains tasks. In this case
3679 -- the call to Init (Temp.all ...) is replaced by code that ensures
3680 -- that tasks get activated (see Exp_Ch9.Build_Task_Allocate_Block
3681 -- for details). In addition, if the type T is a task T, then the
3682 -- first argument to Init must be converted to the task record type.
3685 T : constant Entity_Id := Entity (Expression (N));
3691 Init_Arg1 : Node_Id;
3692 Temp_Decl : Node_Id;
3693 Temp_Type : Entity_Id;
3696 if No_Initialization (N) then
3698 -- Even though this might be a simple allocation, create a custom
3699 -- Allocate if the context requires it. Since .NET/JVM compilers
3700 -- do not support pools, this step is skipped.
3702 if VM_Target = No_VM
3703 and then Present (Finalization_Master (PtrT))
3705 Build_Allocate_Deallocate_Proc
3707 Is_Allocate => True);
3710 -- Case of no initialization procedure present
3712 elsif not Has_Non_Null_Base_Init_Proc (T) then
3714 -- Case of simple initialization required
3716 if Needs_Simple_Initialization (T) then
3717 Check_Restriction (No_Default_Initialization, N);
3718 Rewrite (Expression (N),
3719 Make_Qualified_Expression (Loc,
3720 Subtype_Mark => New_Occurrence_Of (T, Loc),
3721 Expression => Get_Simple_Init_Val (T, N)));
3723 Analyze_And_Resolve (Expression (Expression (N)), T);
3724 Analyze_And_Resolve (Expression (N), T);
3725 Set_Paren_Count (Expression (Expression (N)), 1);
3726 Expand_N_Allocator (N);
3728 -- No initialization required
3734 -- Case of initialization procedure present, must be called
3737 Check_Restriction (No_Default_Initialization, N);
3739 if not Restriction_Active (No_Default_Initialization) then
3740 Init := Base_Init_Proc (T);
3742 Temp := Make_Temporary (Loc, 'P');
3744 -- Construct argument list for the initialization routine call
3747 Make_Explicit_Dereference (Loc,
3749 New_Reference_To (Temp, Loc));
3751 Set_Assignment_OK (Init_Arg1);
3754 -- The initialization procedure expects a specific type. if the
3755 -- context is access to class wide, indicate that the object
3756 -- being allocated has the right specific type.
3758 if Is_Class_Wide_Type (Dtyp) then
3759 Init_Arg1 := Unchecked_Convert_To (T, Init_Arg1);
3762 -- If designated type is a concurrent type or if it is private
3763 -- type whose definition is a concurrent type, the first
3764 -- argument in the Init routine has to be unchecked conversion
3765 -- to the corresponding record type. If the designated type is
3766 -- a derived type, also convert the argument to its root type.
3768 if Is_Concurrent_Type (T) then
3770 Unchecked_Convert_To (
3771 Corresponding_Record_Type (T), Init_Arg1);
3773 elsif Is_Private_Type (T)
3774 and then Present (Full_View (T))
3775 and then Is_Concurrent_Type (Full_View (T))
3778 Unchecked_Convert_To
3779 (Corresponding_Record_Type (Full_View (T)), Init_Arg1);
3781 elsif Etype (First_Formal (Init)) /= Base_Type (T) then
3783 Ftyp : constant Entity_Id := Etype (First_Formal (Init));
3786 Init_Arg1 := OK_Convert_To (Etype (Ftyp), Init_Arg1);
3787 Set_Etype (Init_Arg1, Ftyp);
3791 Args := New_List (Init_Arg1);
3793 -- For the task case, pass the Master_Id of the access type as
3794 -- the value of the _Master parameter, and _Chain as the value
3795 -- of the _Chain parameter (_Chain will be defined as part of
3796 -- the generated code for the allocator).
3798 -- In Ada 2005, the context may be a function that returns an
3799 -- anonymous access type. In that case the Master_Id has been
3800 -- created when expanding the function declaration.
3802 if Has_Task (T) then
3803 if No (Master_Id (Base_Type (PtrT))) then
3805 -- The designated type was an incomplete type, and the
3806 -- access type did not get expanded. Salvage it now.
3808 if not Restriction_Active (No_Task_Hierarchy) then
3809 pragma Assert (Present (Parent (Base_Type (PtrT))));
3810 Expand_N_Full_Type_Declaration
3811 (Parent (Base_Type (PtrT)));
3815 -- If the context of the allocator is a declaration or an
3816 -- assignment, we can generate a meaningful image for it,
3817 -- even though subsequent assignments might remove the
3818 -- connection between task and entity. We build this image
3819 -- when the left-hand side is a simple variable, a simple
3820 -- indexed assignment or a simple selected component.
3822 if Nkind (Parent (N)) = N_Assignment_Statement then
3824 Nam : constant Node_Id := Name (Parent (N));
3827 if Is_Entity_Name (Nam) then
3829 Build_Task_Image_Decls
3832 (Entity (Nam), Sloc (Nam)), T);
3834 elsif Nkind_In (Nam, N_Indexed_Component,
3835 N_Selected_Component)
3836 and then Is_Entity_Name (Prefix (Nam))
3839 Build_Task_Image_Decls
3840 (Loc, Nam, Etype (Prefix (Nam)));
3842 Decls := Build_Task_Image_Decls (Loc, T, T);
3846 elsif Nkind (Parent (N)) = N_Object_Declaration then
3848 Build_Task_Image_Decls
3849 (Loc, Defining_Identifier (Parent (N)), T);
3852 Decls := Build_Task_Image_Decls (Loc, T, T);
3855 if Restriction_Active (No_Task_Hierarchy) then
3857 New_Occurrence_Of (RTE (RE_Library_Task_Level), Loc));
3861 (Master_Id (Base_Type (Root_Type (PtrT))), Loc));
3864 Append_To (Args, Make_Identifier (Loc, Name_uChain));
3866 Decl := Last (Decls);
3868 New_Occurrence_Of (Defining_Identifier (Decl), Loc));
3870 -- Has_Task is false, Decls not used
3876 -- Add discriminants if discriminated type
3879 Dis : Boolean := False;
3883 if Has_Discriminants (T) then
3887 elsif Is_Private_Type (T)
3888 and then Present (Full_View (T))
3889 and then Has_Discriminants (Full_View (T))
3892 Typ := Full_View (T);
3897 -- If the allocated object will be constrained by the
3898 -- default values for discriminants, then build a subtype
3899 -- with those defaults, and change the allocated subtype
3900 -- to that. Note that this happens in fewer cases in Ada
3903 if not Is_Constrained (Typ)
3904 and then Present (Discriminant_Default_Value
3905 (First_Discriminant (Typ)))
3906 and then (Ada_Version < Ada_2005
3908 not Has_Constrained_Partial_View (Typ))
3910 Typ := Build_Default_Subtype (Typ, N);
3911 Set_Expression (N, New_Reference_To (Typ, Loc));
3914 Discr := First_Elmt (Discriminant_Constraint (Typ));
3915 while Present (Discr) loop
3916 Nod := Node (Discr);
3917 Append (New_Copy_Tree (Node (Discr)), Args);
3919 -- AI-416: when the discriminant constraint is an
3920 -- anonymous access type make sure an accessibility
3921 -- check is inserted if necessary (3.10.2(22.q/2))
3923 if Ada_Version >= Ada_2005
3925 Ekind (Etype (Nod)) = E_Anonymous_Access_Type
3927 Apply_Accessibility_Check
3928 (Nod, Typ, Insert_Node => Nod);
3936 -- We set the allocator as analyzed so that when we analyze the
3937 -- expression actions node, we do not get an unwanted recursive
3938 -- expansion of the allocator expression.
3940 Set_Analyzed (N, True);
3941 Nod := Relocate_Node (N);
3943 -- Here is the transformation:
3944 -- input: new Ctrl_Typ
3945 -- output: Temp : constant Ctrl_Typ_Ptr := new Ctrl_Typ;
3946 -- Ctrl_TypIP (Temp.all, ...);
3947 -- [Deep_]Initialize (Temp.all);
3949 -- Here Ctrl_Typ_Ptr is the pointer type for the allocator, and
3950 -- is the subtype of the allocator.
3953 Make_Object_Declaration (Loc,
3954 Defining_Identifier => Temp,
3955 Constant_Present => True,
3956 Object_Definition => New_Reference_To (Temp_Type, Loc),
3959 Set_Assignment_OK (Temp_Decl);
3960 Insert_Action (N, Temp_Decl, Suppress => All_Checks);
3962 Build_Allocate_Deallocate_Proc (Temp_Decl, True);
3964 -- If the designated type is a task type or contains tasks,
3965 -- create block to activate created tasks, and insert
3966 -- declaration for Task_Image variable ahead of call.
3968 if Has_Task (T) then
3970 L : constant List_Id := New_List;
3973 Build_Task_Allocate_Block (L, Nod, Args);
3975 Insert_List_Before (First (Declarations (Blk)), Decls);
3976 Insert_Actions (N, L);
3981 Make_Procedure_Call_Statement (Loc,
3982 Name => New_Reference_To (Init, Loc),
3983 Parameter_Associations => Args));
3986 if Needs_Finalization (T) then
3989 -- [Deep_]Initialize (Init_Arg1);
3993 (Obj_Ref => New_Copy_Tree (Init_Arg1),
3996 if Present (Finalization_Master (PtrT)) then
3998 -- Special processing for .NET/JVM, the allocated object
3999 -- is attached to the finalization master. Generate:
4001 -- Attach (<PtrT>FM, Root_Controlled_Ptr (Init_Arg1));
4003 -- Types derived from [Limited_]Controlled are the only
4004 -- ones considered since they have fields Prev and Next.
4006 if VM_Target /= No_VM then
4007 if Is_Controlled (T) then
4010 (Obj_Ref => New_Copy_Tree (Init_Arg1),
4014 -- Default case, generate:
4016 -- Set_Finalize_Address
4017 -- (<PtrT>FM, <T>FD'Unrestricted_Access);
4019 -- Do not generate this call in the following cases:
4021 -- * Alfa mode - the call is useless and results in
4022 -- unwanted expansion.
4024 -- * CodePeer mode - TSS primitive Finalize_Address is
4025 -- not created in this mode.
4028 and then not CodePeer_Mode
4031 Make_Set_Finalize_Address_Call
4039 Rewrite (N, New_Reference_To (Temp, Loc));
4040 Analyze_And_Resolve (N, PtrT);
4045 -- Ada 2005 (AI-251): If the allocator is for a class-wide interface
4046 -- object that has been rewritten as a reference, we displace "this"
4047 -- to reference properly its secondary dispatch table.
4049 if Nkind (N) = N_Identifier
4050 and then Is_Interface (Dtyp)
4052 Displace_Allocator_Pointer (N);
4056 when RE_Not_Available =>
4058 end Expand_N_Allocator;
4060 -----------------------
4061 -- Expand_N_And_Then --
4062 -----------------------
4064 procedure Expand_N_And_Then (N : Node_Id)
4065 renames Expand_Short_Circuit_Operator;
4067 ------------------------------
4068 -- Expand_N_Case_Expression --
4069 ------------------------------
4071 procedure Expand_N_Case_Expression (N : Node_Id) is
4072 Loc : constant Source_Ptr := Sloc (N);
4073 Typ : constant Entity_Id := Etype (N);
4085 -- case X is when A => AX, when B => BX ...
4100 -- However, this expansion is wrong for limited types, and also
4101 -- wrong for unconstrained types (since the bounds may not be the
4102 -- same in all branches). Furthermore it involves an extra copy
4103 -- for large objects. So we take care of this by using the following
4104 -- modified expansion for non-scalar types:
4107 -- type Pnn is access all typ;
4111 -- T := AX'Unrestricted_Access;
4113 -- T := BX'Unrestricted_Access;
4119 Make_Case_Statement (Loc,
4120 Expression => Expression (N),
4121 Alternatives => New_List);
4123 Actions := New_List;
4127 if Is_Scalar_Type (Typ) then
4131 Pnn := Make_Temporary (Loc, 'P');
4133 Make_Full_Type_Declaration (Loc,
4134 Defining_Identifier => Pnn,
4136 Make_Access_To_Object_Definition (Loc,
4137 All_Present => True,
4138 Subtype_Indication =>
4139 New_Reference_To (Typ, Loc))));
4143 Tnn := Make_Temporary (Loc, 'T');
4145 Make_Object_Declaration (Loc,
4146 Defining_Identifier => Tnn,
4147 Object_Definition => New_Occurrence_Of (Ttyp, Loc)));
4149 -- Now process the alternatives
4151 Alt := First (Alternatives (N));
4152 while Present (Alt) loop
4154 Aexp : Node_Id := Expression (Alt);
4155 Aloc : constant Source_Ptr := Sloc (Aexp);
4159 -- As described above, take Unrestricted_Access for case of non-
4160 -- scalar types, to avoid big copies, and special cases.
4162 if not Is_Scalar_Type (Typ) then
4164 Make_Attribute_Reference (Aloc,
4165 Prefix => Relocate_Node (Aexp),
4166 Attribute_Name => Name_Unrestricted_Access);
4170 Make_Assignment_Statement (Aloc,
4171 Name => New_Occurrence_Of (Tnn, Loc),
4172 Expression => Aexp));
4174 -- Propagate declarations inserted in the node by Insert_Actions
4175 -- (for example, temporaries generated to remove side effects).
4176 -- These actions must remain attached to the alternative, given
4177 -- that they are generated by the corresponding expression.
4179 if Present (Sinfo.Actions (Alt)) then
4180 Prepend_List (Sinfo.Actions (Alt), Stats);
4184 (Alternatives (Cstmt),
4185 Make_Case_Statement_Alternative (Sloc (Alt),
4186 Discrete_Choices => Discrete_Choices (Alt),
4187 Statements => Stats));
4193 Append_To (Actions, Cstmt);
4195 -- Construct and return final expression with actions
4197 if Is_Scalar_Type (Typ) then
4198 Fexp := New_Occurrence_Of (Tnn, Loc);
4201 Make_Explicit_Dereference (Loc,
4202 Prefix => New_Occurrence_Of (Tnn, Loc));
4206 Make_Expression_With_Actions (Loc,
4208 Actions => Actions));
4210 Analyze_And_Resolve (N, Typ);
4211 end Expand_N_Case_Expression;
4213 -------------------------------------
4214 -- Expand_N_Conditional_Expression --
4215 -------------------------------------
4217 -- Deal with limited types and expression actions
4219 procedure Expand_N_Conditional_Expression (N : Node_Id) is
4220 Loc : constant Source_Ptr := Sloc (N);
4221 Cond : constant Node_Id := First (Expressions (N));
4222 Thenx : constant Node_Id := Next (Cond);
4223 Elsex : constant Node_Id := Next (Thenx);
4224 Typ : constant Entity_Id := Etype (N);
4235 -- Fold at compile time if condition known. We have already folded
4236 -- static conditional expressions, but it is possible to fold any
4237 -- case in which the condition is known at compile time, even though
4238 -- the result is non-static.
4240 -- Note that we don't do the fold of such cases in Sem_Elab because
4241 -- it can cause infinite loops with the expander adding a conditional
4242 -- expression, and Sem_Elab circuitry removing it repeatedly.
4244 if Compile_Time_Known_Value (Cond) then
4245 if Is_True (Expr_Value (Cond)) then
4247 Actions := Then_Actions (N);
4250 Actions := Else_Actions (N);
4255 if Present (Actions) then
4257 -- If we are not allowed to use Expression_With_Actions, just skip
4258 -- the optimization, it is not critical for correctness.
4260 if not Use_Expression_With_Actions then
4261 goto Skip_Optimization;
4265 Make_Expression_With_Actions (Loc,
4266 Expression => Relocate_Node (Expr),
4267 Actions => Actions));
4268 Analyze_And_Resolve (N, Typ);
4271 Rewrite (N, Relocate_Node (Expr));
4274 -- Note that the result is never static (legitimate cases of static
4275 -- conditional expressions were folded in Sem_Eval).
4277 Set_Is_Static_Expression (N, False);
4281 <<Skip_Optimization>>
4283 -- If the type is limited or unconstrained, we expand as follows to
4284 -- avoid any possibility of improper copies.
4286 -- Note: it may be possible to avoid this special processing if the
4287 -- back end uses its own mechanisms for handling by-reference types ???
4289 -- type Ptr is access all Typ;
4293 -- Cnn := then-expr'Unrestricted_Access;
4296 -- Cnn := else-expr'Unrestricted_Access;
4299 -- and replace the conditional expression by a reference to Cnn.all.
4301 -- This special case can be skipped if the back end handles limited
4302 -- types properly and ensures that no incorrect copies are made.
4304 if Is_By_Reference_Type (Typ)
4305 and then not Back_End_Handles_Limited_Types
4307 Cnn := Make_Temporary (Loc, 'C', N);
4310 Make_Full_Type_Declaration (Loc,
4311 Defining_Identifier =>
4312 Make_Temporary (Loc, 'A'),
4314 Make_Access_To_Object_Definition (Loc,
4315 All_Present => True,
4316 Subtype_Indication => New_Reference_To (Typ, Loc)));
4318 Insert_Action (N, P_Decl);
4321 Make_Object_Declaration (Loc,
4322 Defining_Identifier => Cnn,
4323 Object_Definition =>
4324 New_Occurrence_Of (Defining_Identifier (P_Decl), Loc));
4327 Make_Implicit_If_Statement (N,
4328 Condition => Relocate_Node (Cond),
4330 Then_Statements => New_List (
4331 Make_Assignment_Statement (Sloc (Thenx),
4332 Name => New_Occurrence_Of (Cnn, Sloc (Thenx)),
4334 Make_Attribute_Reference (Loc,
4335 Attribute_Name => Name_Unrestricted_Access,
4336 Prefix => Relocate_Node (Thenx)))),
4338 Else_Statements => New_List (
4339 Make_Assignment_Statement (Sloc (Elsex),
4340 Name => New_Occurrence_Of (Cnn, Sloc (Elsex)),
4342 Make_Attribute_Reference (Loc,
4343 Attribute_Name => Name_Unrestricted_Access,
4344 Prefix => Relocate_Node (Elsex)))));
4347 Make_Explicit_Dereference (Loc,
4348 Prefix => New_Occurrence_Of (Cnn, Loc));
4350 -- For other types, we only need to expand if there are other actions
4351 -- associated with either branch.
4353 elsif Present (Then_Actions (N)) or else Present (Else_Actions (N)) then
4355 -- We have two approaches to handling this. If we are allowed to use
4356 -- N_Expression_With_Actions, then we can just wrap the actions into
4357 -- the appropriate expression.
4359 if Use_Expression_With_Actions then
4360 if Present (Then_Actions (N)) then
4362 Make_Expression_With_Actions (Sloc (Thenx),
4363 Actions => Then_Actions (N),
4364 Expression => Relocate_Node (Thenx)));
4365 Set_Then_Actions (N, No_List);
4366 Analyze_And_Resolve (Thenx, Typ);
4369 if Present (Else_Actions (N)) then
4371 Make_Expression_With_Actions (Sloc (Elsex),
4372 Actions => Else_Actions (N),
4373 Expression => Relocate_Node (Elsex)));
4374 Set_Else_Actions (N, No_List);
4375 Analyze_And_Resolve (Elsex, Typ);
4380 -- if we can't use N_Expression_With_Actions nodes, then we insert
4381 -- the following sequence of actions (using Insert_Actions):
4386 -- Cnn := then-expr;
4392 -- and replace the conditional expression by a reference to Cnn
4395 Cnn := Make_Temporary (Loc, 'C', N);
4398 Make_Object_Declaration (Loc,
4399 Defining_Identifier => Cnn,
4400 Object_Definition => New_Occurrence_Of (Typ, Loc));
4403 Make_Implicit_If_Statement (N,
4404 Condition => Relocate_Node (Cond),
4406 Then_Statements => New_List (
4407 Make_Assignment_Statement (Sloc (Thenx),
4408 Name => New_Occurrence_Of (Cnn, Sloc (Thenx)),
4409 Expression => Relocate_Node (Thenx))),
4411 Else_Statements => New_List (
4412 Make_Assignment_Statement (Sloc (Elsex),
4413 Name => New_Occurrence_Of (Cnn, Sloc (Elsex)),
4414 Expression => Relocate_Node (Elsex))));
4416 Set_Assignment_OK (Name (First (Then_Statements (New_If))));
4417 Set_Assignment_OK (Name (First (Else_Statements (New_If))));
4419 New_N := New_Occurrence_Of (Cnn, Loc);
4422 -- If no actions then no expansion needed, gigi will handle it using
4423 -- the same approach as a C conditional expression.
4429 -- Fall through here for either the limited expansion, or the case of
4430 -- inserting actions for non-limited types. In both these cases, we must
4431 -- move the SLOC of the parent If statement to the newly created one and
4432 -- change it to the SLOC of the expression which, after expansion, will
4433 -- correspond to what is being evaluated.
4435 if Present (Parent (N))
4436 and then Nkind (Parent (N)) = N_If_Statement
4438 Set_Sloc (New_If, Sloc (Parent (N)));
4439 Set_Sloc (Parent (N), Loc);
4442 -- Make sure Then_Actions and Else_Actions are appropriately moved
4443 -- to the new if statement.
4445 if Present (Then_Actions (N)) then
4447 (First (Then_Statements (New_If)), Then_Actions (N));
4450 if Present (Else_Actions (N)) then
4452 (First (Else_Statements (New_If)), Else_Actions (N));
4455 Insert_Action (N, Decl);
4456 Insert_Action (N, New_If);
4458 Analyze_And_Resolve (N, Typ);
4459 end Expand_N_Conditional_Expression;
4461 -----------------------------------
4462 -- Expand_N_Explicit_Dereference --
4463 -----------------------------------
4465 procedure Expand_N_Explicit_Dereference (N : Node_Id) is
4467 -- Insert explicit dereference call for the checked storage pool case
4469 Insert_Dereference_Action (Prefix (N));
4470 end Expand_N_Explicit_Dereference;
4472 --------------------------------------
4473 -- Expand_N_Expression_With_Actions --
4474 --------------------------------------
4476 procedure Expand_N_Expression_With_Actions (N : Node_Id) is
4478 procedure Process_Transient_Object (Decl : Node_Id);
4479 -- Given the declaration of a controlled transient declared inside the
4480 -- Actions list of an Expression_With_Actions, generate all necessary
4481 -- types and hooks in order to properly finalize the transient. This
4482 -- mechanism works in conjunction with Build_Finalizer.
4484 ------------------------------
4485 -- Process_Transient_Object --
4486 ------------------------------
4488 procedure Process_Transient_Object (Decl : Node_Id) is
4490 function Find_Insertion_Node return Node_Id;
4491 -- Complex conditions in if statements may be converted into nested
4492 -- EWAs. In this case, any generated code must be inserted before the
4493 -- if statement to ensure proper visibility of the hook objects. This
4494 -- routine returns the top most short circuit operator or the parent
4495 -- of the EWA if no nesting was detected.
4497 -------------------------
4498 -- Find_Insertion_Node --
4499 -------------------------
4501 function Find_Insertion_Node return Node_Id is
4505 -- Climb up the branches of a complex condition
4508 while Nkind_In (Parent (Par), N_And_Then, N_Op_Not, N_Or_Else) loop
4509 Par := Parent (Par);
4513 end Find_Insertion_Node;
4517 Ins_Node : constant Node_Id := Find_Insertion_Node;
4518 Loc : constant Source_Ptr := Sloc (Decl);
4519 Obj_Id : constant Entity_Id := Defining_Identifier (Decl);
4520 Obj_Typ : constant Entity_Id := Etype (Obj_Id);
4521 Desig_Typ : Entity_Id;
4525 Temp_Decl : Node_Id;
4528 -- Start of processing for Process_Transient_Object
4531 -- Step 1: Create the access type which provides a reference to the
4532 -- transient object.
4534 if Is_Access_Type (Obj_Typ) then
4535 Desig_Typ := Directly_Designated_Type (Obj_Typ);
4537 Desig_Typ := Obj_Typ;
4541 -- Ann : access [all] <Desig_Typ>;
4543 Ptr_Id := Make_Temporary (Loc, 'A');
4546 Make_Full_Type_Declaration (Loc,
4547 Defining_Identifier => Ptr_Id,
4549 Make_Access_To_Object_Definition (Loc,
4551 Ekind (Obj_Typ) = E_General_Access_Type,
4552 Subtype_Indication => New_Reference_To (Desig_Typ, Loc)));
4554 Insert_Action (Ins_Node, Ptr_Decl);
4557 -- Step 2: Create a temporary which acts as a hook to the transient
4558 -- object. Generate:
4560 -- Temp : Ptr_Id := null;
4562 Temp_Id := Make_Temporary (Loc, 'T');
4565 Make_Object_Declaration (Loc,
4566 Defining_Identifier => Temp_Id,
4567 Object_Definition => New_Reference_To (Ptr_Id, Loc));
4569 Insert_Action (Ins_Node, Temp_Decl);
4570 Analyze (Temp_Decl);
4572 -- Mark this temporary as created for the purposes of exporting the
4573 -- transient declaration out of the Actions list. This signals the
4574 -- machinery in Build_Finalizer to recognize this special case.
4576 Set_Return_Flag_Or_Transient_Decl (Temp_Id, Decl);
4578 -- Step 3: Hook the transient object to the temporary
4580 if Is_Access_Type (Obj_Typ) then
4581 Expr := Convert_To (Ptr_Id, New_Reference_To (Obj_Id, Loc));
4584 Make_Attribute_Reference (Loc,
4585 Prefix => New_Reference_To (Obj_Id, Loc),
4586 Attribute_Name => Name_Unrestricted_Access);
4590 -- Temp := Ptr_Id (Obj_Id);
4592 -- Temp := Obj_Id'Unrestricted_Access;
4594 Insert_After_And_Analyze (Decl,
4595 Make_Assignment_Statement (Loc,
4596 Name => New_Reference_To (Temp_Id, Loc),
4597 Expression => Expr));
4598 end Process_Transient_Object;
4604 -- Start of processing for Expand_N_Expression_With_Actions
4607 Decl := First (Actions (N));
4608 while Present (Decl) loop
4609 if Nkind (Decl) = N_Object_Declaration
4610 and then Is_Finalizable_Transient (Decl, N)
4612 Process_Transient_Object (Decl);
4617 end Expand_N_Expression_With_Actions;
4623 procedure Expand_N_In (N : Node_Id) is
4624 Loc : constant Source_Ptr := Sloc (N);
4625 Restyp : constant Entity_Id := Etype (N);
4626 Lop : constant Node_Id := Left_Opnd (N);
4627 Rop : constant Node_Id := Right_Opnd (N);
4628 Static : constant Boolean := Is_OK_Static_Expression (N);
4633 procedure Substitute_Valid_Check;
4634 -- Replaces node N by Lop'Valid. This is done when we have an explicit
4635 -- test for the left operand being in range of its subtype.
4637 ----------------------------
4638 -- Substitute_Valid_Check --
4639 ----------------------------
4641 procedure Substitute_Valid_Check is
4644 Make_Attribute_Reference (Loc,
4645 Prefix => Relocate_Node (Lop),
4646 Attribute_Name => Name_Valid));
4648 Analyze_And_Resolve (N, Restyp);
4650 Error_Msg_N ("?explicit membership test may be optimized away", N);
4651 Error_Msg_N -- CODEFIX
4652 ("\?use ''Valid attribute instead", N);
4654 end Substitute_Valid_Check;
4656 -- Start of processing for Expand_N_In
4659 -- If set membership case, expand with separate procedure
4661 if Present (Alternatives (N)) then
4662 Expand_Set_Membership (N);
4666 -- Not set membership, proceed with expansion
4668 Ltyp := Etype (Left_Opnd (N));
4669 Rtyp := Etype (Right_Opnd (N));
4671 -- Check case of explicit test for an expression in range of its
4672 -- subtype. This is suspicious usage and we replace it with a 'Valid
4673 -- test and give a warning. For floating point types however, this is a
4674 -- standard way to check for finite numbers, and using 'Valid would
4675 -- typically be a pessimization. Also skip this test for predicated
4676 -- types, since it is perfectly reasonable to check if a value meets
4679 if Is_Scalar_Type (Ltyp)
4680 and then not Is_Floating_Point_Type (Ltyp)
4681 and then Nkind (Rop) in N_Has_Entity
4682 and then Ltyp = Entity (Rop)
4683 and then Comes_From_Source (N)
4684 and then VM_Target = No_VM
4685 and then not (Is_Discrete_Type (Ltyp)
4686 and then Present (Predicate_Function (Ltyp)))
4688 Substitute_Valid_Check;
4692 -- Do validity check on operands
4694 if Validity_Checks_On and Validity_Check_Operands then
4695 Ensure_Valid (Left_Opnd (N));
4696 Validity_Check_Range (Right_Opnd (N));
4699 -- Case of explicit range
4701 if Nkind (Rop) = N_Range then
4703 Lo : constant Node_Id := Low_Bound (Rop);
4704 Hi : constant Node_Id := High_Bound (Rop);
4706 Lo_Orig : constant Node_Id := Original_Node (Lo);
4707 Hi_Orig : constant Node_Id := Original_Node (Hi);
4709 Lcheck : Compare_Result;
4710 Ucheck : Compare_Result;
4712 Warn1 : constant Boolean :=
4713 Constant_Condition_Warnings
4714 and then Comes_From_Source (N)
4715 and then not In_Instance;
4716 -- This must be true for any of the optimization warnings, we
4717 -- clearly want to give them only for source with the flag on. We
4718 -- also skip these warnings in an instance since it may be the
4719 -- case that different instantiations have different ranges.
4721 Warn2 : constant Boolean :=
4723 and then Nkind (Original_Node (Rop)) = N_Range
4724 and then Is_Integer_Type (Etype (Lo));
4725 -- For the case where only one bound warning is elided, we also
4726 -- insist on an explicit range and an integer type. The reason is
4727 -- that the use of enumeration ranges including an end point is
4728 -- common, as is the use of a subtype name, one of whose bounds is
4729 -- the same as the type of the expression.
4732 -- If test is explicit x'First .. x'Last, replace by valid check
4734 -- Could use some individual comments for this complex test ???
4736 if Is_Scalar_Type (Ltyp)
4737 and then Nkind (Lo_Orig) = N_Attribute_Reference
4738 and then Attribute_Name (Lo_Orig) = Name_First
4739 and then Nkind (Prefix (Lo_Orig)) in N_Has_Entity
4740 and then Entity (Prefix (Lo_Orig)) = Ltyp
4741 and then Nkind (Hi_Orig) = N_Attribute_Reference
4742 and then Attribute_Name (Hi_Orig) = Name_Last
4743 and then Nkind (Prefix (Hi_Orig)) in N_Has_Entity
4744 and then Entity (Prefix (Hi_Orig)) = Ltyp
4745 and then Comes_From_Source (N)
4746 and then VM_Target = No_VM
4748 Substitute_Valid_Check;
4752 -- If bounds of type are known at compile time, and the end points
4753 -- are known at compile time and identical, this is another case
4754 -- for substituting a valid test. We only do this for discrete
4755 -- types, since it won't arise in practice for float types.
4757 if Comes_From_Source (N)
4758 and then Is_Discrete_Type (Ltyp)
4759 and then Compile_Time_Known_Value (Type_High_Bound (Ltyp))
4760 and then Compile_Time_Known_Value (Type_Low_Bound (Ltyp))
4761 and then Compile_Time_Known_Value (Lo)
4762 and then Compile_Time_Known_Value (Hi)
4763 and then Expr_Value (Type_High_Bound (Ltyp)) = Expr_Value (Hi)
4764 and then Expr_Value (Type_Low_Bound (Ltyp)) = Expr_Value (Lo)
4766 -- Kill warnings in instances, since they may be cases where we
4767 -- have a test in the generic that makes sense with some types
4768 -- and not with other types.
4770 and then not In_Instance
4772 Substitute_Valid_Check;
4776 -- If we have an explicit range, do a bit of optimization based on
4777 -- range analysis (we may be able to kill one or both checks).
4779 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => False);
4780 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => False);
4782 -- If either check is known to fail, replace result by False since
4783 -- the other check does not matter. Preserve the static flag for
4784 -- legality checks, because we are constant-folding beyond RM 4.9.
4786 if Lcheck = LT or else Ucheck = GT then
4788 Error_Msg_N ("?range test optimized away", N);
4789 Error_Msg_N ("\?value is known to be out of range", N);
4792 Rewrite (N, New_Reference_To (Standard_False, Loc));
4793 Analyze_And_Resolve (N, Restyp);
4794 Set_Is_Static_Expression (N, Static);
4797 -- If both checks are known to succeed, replace result by True,
4798 -- since we know we are in range.
4800 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
4802 Error_Msg_N ("?range test optimized away", N);
4803 Error_Msg_N ("\?value is known to be in range", N);
4806 Rewrite (N, New_Reference_To (Standard_True, Loc));
4807 Analyze_And_Resolve (N, Restyp);
4808 Set_Is_Static_Expression (N, Static);
4811 -- If lower bound check succeeds and upper bound check is not
4812 -- known to succeed or fail, then replace the range check with
4813 -- a comparison against the upper bound.
4815 elsif Lcheck in Compare_GE then
4816 if Warn2 and then not In_Instance then
4817 Error_Msg_N ("?lower bound test optimized away", Lo);
4818 Error_Msg_N ("\?value is known to be in range", Lo);
4824 Right_Opnd => High_Bound (Rop)));
4825 Analyze_And_Resolve (N, Restyp);
4828 -- If upper bound check succeeds and lower bound check is not
4829 -- known to succeed or fail, then replace the range check with
4830 -- a comparison against the lower bound.
4832 elsif Ucheck in Compare_LE then
4833 if Warn2 and then not In_Instance then
4834 Error_Msg_N ("?upper bound test optimized away", Hi);
4835 Error_Msg_N ("\?value is known to be in range", Hi);
4841 Right_Opnd => Low_Bound (Rop)));
4842 Analyze_And_Resolve (N, Restyp);
4846 -- We couldn't optimize away the range check, but there is one
4847 -- more issue. If we are checking constant conditionals, then we
4848 -- see if we can determine the outcome assuming everything is
4849 -- valid, and if so give an appropriate warning.
4851 if Warn1 and then not Assume_No_Invalid_Values then
4852 Lcheck := Compile_Time_Compare (Lop, Lo, Assume_Valid => True);
4853 Ucheck := Compile_Time_Compare (Lop, Hi, Assume_Valid => True);
4855 -- Result is out of range for valid value
4857 if Lcheck = LT or else Ucheck = GT then
4859 ("?value can only be in range if it is invalid", N);
4861 -- Result is in range for valid value
4863 elsif Lcheck in Compare_GE and then Ucheck in Compare_LE then
4865 ("?value can only be out of range if it is invalid", N);
4867 -- Lower bound check succeeds if value is valid
4869 elsif Warn2 and then Lcheck in Compare_GE then
4871 ("?lower bound check only fails if it is invalid", Lo);
4873 -- Upper bound check succeeds if value is valid
4875 elsif Warn2 and then Ucheck in Compare_LE then
4877 ("?upper bound check only fails for invalid values", Hi);
4882 -- For all other cases of an explicit range, nothing to be done
4886 -- Here right operand is a subtype mark
4890 Typ : Entity_Id := Etype (Rop);
4891 Is_Acc : constant Boolean := Is_Access_Type (Typ);
4892 Cond : Node_Id := Empty;
4894 Obj : Node_Id := Lop;
4895 SCIL_Node : Node_Id;
4898 Remove_Side_Effects (Obj);
4900 -- For tagged type, do tagged membership operation
4902 if Is_Tagged_Type (Typ) then
4904 -- No expansion will be performed when VM_Target, as the VM
4905 -- back-ends will handle the membership tests directly (tags
4906 -- are not explicitly represented in Java objects, so the
4907 -- normal tagged membership expansion is not what we want).
4909 if Tagged_Type_Expansion then
4910 Tagged_Membership (N, SCIL_Node, New_N);
4912 Analyze_And_Resolve (N, Restyp);
4914 -- Update decoration of relocated node referenced by the
4917 if Generate_SCIL and then Present (SCIL_Node) then
4918 Set_SCIL_Node (N, SCIL_Node);
4924 -- If type is scalar type, rewrite as x in t'First .. t'Last.
4925 -- This reason we do this is that the bounds may have the wrong
4926 -- type if they come from the original type definition. Also this
4927 -- way we get all the processing above for an explicit range.
4929 -- Don't do this for predicated types, since in this case we
4930 -- want to check the predicate!
4932 elsif Is_Scalar_Type (Typ) then
4933 if No (Predicate_Function (Typ)) then
4937 Make_Attribute_Reference (Loc,
4938 Attribute_Name => Name_First,
4939 Prefix => New_Reference_To (Typ, Loc)),
4942 Make_Attribute_Reference (Loc,
4943 Attribute_Name => Name_Last,
4944 Prefix => New_Reference_To (Typ, Loc))));
4945 Analyze_And_Resolve (N, Restyp);
4950 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
4951 -- a membership test if the subtype mark denotes a constrained
4952 -- Unchecked_Union subtype and the expression lacks inferable
4955 elsif Is_Unchecked_Union (Base_Type (Typ))
4956 and then Is_Constrained (Typ)
4957 and then not Has_Inferable_Discriminants (Lop)
4960 Make_Raise_Program_Error (Loc,
4961 Reason => PE_Unchecked_Union_Restriction));
4963 -- Prevent Gigi from generating incorrect code by rewriting the
4966 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
4970 -- Here we have a non-scalar type
4973 Typ := Designated_Type (Typ);
4976 if not Is_Constrained (Typ) then
4977 Rewrite (N, New_Reference_To (Standard_True, Loc));
4978 Analyze_And_Resolve (N, Restyp);
4980 -- For the constrained array case, we have to check the subscripts
4981 -- for an exact match if the lengths are non-zero (the lengths
4982 -- must match in any case).
4984 elsif Is_Array_Type (Typ) then
4985 Check_Subscripts : declare
4986 function Build_Attribute_Reference
4989 Dim : Nat) return Node_Id;
4990 -- Build attribute reference E'Nam (Dim)
4992 -------------------------------
4993 -- Build_Attribute_Reference --
4994 -------------------------------
4996 function Build_Attribute_Reference
4999 Dim : Nat) return Node_Id
5003 Make_Attribute_Reference (Loc,
5005 Attribute_Name => Nam,
5006 Expressions => New_List (
5007 Make_Integer_Literal (Loc, Dim)));
5008 end Build_Attribute_Reference;
5010 -- Start of processing for Check_Subscripts
5013 for J in 1 .. Number_Dimensions (Typ) loop
5014 Evolve_And_Then (Cond,
5017 Build_Attribute_Reference
5018 (Duplicate_Subexpr_No_Checks (Obj),
5021 Build_Attribute_Reference
5022 (New_Occurrence_Of (Typ, Loc), Name_First, J)));
5024 Evolve_And_Then (Cond,
5027 Build_Attribute_Reference
5028 (Duplicate_Subexpr_No_Checks (Obj),
5031 Build_Attribute_Reference
5032 (New_Occurrence_Of (Typ, Loc), Name_Last, J)));
5041 Right_Opnd => Make_Null (Loc)),
5042 Right_Opnd => Cond);
5046 Analyze_And_Resolve (N, Restyp);
5047 end Check_Subscripts;
5049 -- These are the cases where constraint checks may be required,
5050 -- e.g. records with possible discriminants
5053 -- Expand the test into a series of discriminant comparisons.
5054 -- The expression that is built is the negation of the one that
5055 -- is used for checking discriminant constraints.
5057 Obj := Relocate_Node (Left_Opnd (N));
5059 if Has_Discriminants (Typ) then
5060 Cond := Make_Op_Not (Loc,
5061 Right_Opnd => Build_Discriminant_Checks (Obj, Typ));
5064 Cond := Make_Or_Else (Loc,
5068 Right_Opnd => Make_Null (Loc)),
5069 Right_Opnd => Cond);
5073 Cond := New_Occurrence_Of (Standard_True, Loc);
5077 Analyze_And_Resolve (N, Restyp);
5080 -- Ada 2012 (AI05-0149): Handle membership tests applied to an
5081 -- expression of an anonymous access type. This can involve an
5082 -- accessibility test and a tagged type membership test in the
5083 -- case of tagged designated types.
5085 if Ada_Version >= Ada_2012
5087 and then Ekind (Ltyp) = E_Anonymous_Access_Type
5090 Expr_Entity : Entity_Id := Empty;
5092 Param_Level : Node_Id;
5093 Type_Level : Node_Id;
5096 if Is_Entity_Name (Lop) then
5097 Expr_Entity := Param_Entity (Lop);
5099 if not Present (Expr_Entity) then
5100 Expr_Entity := Entity (Lop);
5104 -- If a conversion of the anonymous access value to the
5105 -- tested type would be illegal, then the result is False.
5107 if not Valid_Conversion
5108 (Lop, Rtyp, Lop, Report_Errs => False)
5110 Rewrite (N, New_Occurrence_Of (Standard_False, Loc));
5111 Analyze_And_Resolve (N, Restyp);
5113 -- Apply an accessibility check if the access object has an
5114 -- associated access level and when the level of the type is
5115 -- less deep than the level of the access parameter. This
5116 -- only occur for access parameters and stand-alone objects
5117 -- of an anonymous access type.
5120 if Present (Expr_Entity)
5123 (Effective_Extra_Accessibility (Expr_Entity))
5124 and then UI_Gt (Object_Access_Level (Lop),
5125 Type_Access_Level (Rtyp))
5129 (Effective_Extra_Accessibility (Expr_Entity), Loc);
5132 Make_Integer_Literal (Loc, Type_Access_Level (Rtyp));
5134 -- Return True only if the accessibility level of the
5135 -- expression entity is not deeper than the level of
5136 -- the tested access type.
5140 Left_Opnd => Relocate_Node (N),
5141 Right_Opnd => Make_Op_Le (Loc,
5142 Left_Opnd => Param_Level,
5143 Right_Opnd => Type_Level)));
5145 Analyze_And_Resolve (N);
5148 -- If the designated type is tagged, do tagged membership
5151 -- *** NOTE: we have to check not null before doing the
5152 -- tagged membership test (but maybe that can be done
5153 -- inside Tagged_Membership?).
5155 if Is_Tagged_Type (Typ) then
5158 Left_Opnd => Relocate_Node (N),
5162 Right_Opnd => Make_Null (Loc))));
5164 -- No expansion will be performed when VM_Target, as
5165 -- the VM back-ends will handle the membership tests
5166 -- directly (tags are not explicitly represented in
5167 -- Java objects, so the normal tagged membership
5168 -- expansion is not what we want).
5170 if Tagged_Type_Expansion then
5172 -- Note that we have to pass Original_Node, because
5173 -- the membership test might already have been
5174 -- rewritten by earlier parts of membership test.
5177 (Original_Node (N), SCIL_Node, New_N);
5179 -- Update decoration of relocated node referenced
5180 -- by the SCIL node.
5182 if Generate_SCIL and then Present (SCIL_Node) then
5183 Set_SCIL_Node (New_N, SCIL_Node);
5188 Left_Opnd => Relocate_Node (N),
5189 Right_Opnd => New_N));
5191 Analyze_And_Resolve (N, Restyp);
5200 -- At this point, we have done the processing required for the basic
5201 -- membership test, but not yet dealt with the predicate.
5205 -- If a predicate is present, then we do the predicate test, but we
5206 -- most certainly want to omit this if we are within the predicate
5207 -- function itself, since otherwise we have an infinite recursion!
5210 PFunc : constant Entity_Id := Predicate_Function (Rtyp);
5214 and then Current_Scope /= PFunc
5218 Left_Opnd => Relocate_Node (N),
5219 Right_Opnd => Make_Predicate_Call (Rtyp, Lop)));
5221 -- Analyze new expression, mark left operand as analyzed to
5222 -- avoid infinite recursion adding predicate calls.
5224 Set_Analyzed (Left_Opnd (N));
5225 Analyze_And_Resolve (N, Standard_Boolean);
5227 -- All done, skip attempt at compile time determination of result
5234 --------------------------------
5235 -- Expand_N_Indexed_Component --
5236 --------------------------------
5238 procedure Expand_N_Indexed_Component (N : Node_Id) is
5239 Loc : constant Source_Ptr := Sloc (N);
5240 Typ : constant Entity_Id := Etype (N);
5241 P : constant Node_Id := Prefix (N);
5242 T : constant Entity_Id := Etype (P);
5245 -- A special optimization, if we have an indexed component that is
5246 -- selecting from a slice, then we can eliminate the slice, since, for
5247 -- example, x (i .. j)(k) is identical to x(k). The only difference is
5248 -- the range check required by the slice. The range check for the slice
5249 -- itself has already been generated. The range check for the
5250 -- subscripting operation is ensured by converting the subject to
5251 -- the subtype of the slice.
5253 -- This optimization not only generates better code, avoiding slice
5254 -- messing especially in the packed case, but more importantly bypasses
5255 -- some problems in handling this peculiar case, for example, the issue
5256 -- of dealing specially with object renamings.
5258 if Nkind (P) = N_Slice then
5260 Make_Indexed_Component (Loc,
5261 Prefix => Prefix (P),
5262 Expressions => New_List (
5264 (Etype (First_Index (Etype (P))),
5265 First (Expressions (N))))));
5266 Analyze_And_Resolve (N, Typ);
5270 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
5271 -- function, then additional actuals must be passed.
5273 if Ada_Version >= Ada_2005
5274 and then Is_Build_In_Place_Function_Call (P)
5276 Make_Build_In_Place_Call_In_Anonymous_Context (P);
5279 -- If the prefix is an access type, then we unconditionally rewrite if
5280 -- as an explicit dereference. This simplifies processing for several
5281 -- cases, including packed array cases and certain cases in which checks
5282 -- must be generated. We used to try to do this only when it was
5283 -- necessary, but it cleans up the code to do it all the time.
5285 if Is_Access_Type (T) then
5286 Insert_Explicit_Dereference (P);
5287 Analyze_And_Resolve (P, Designated_Type (T));
5290 -- Generate index and validity checks
5292 Generate_Index_Checks (N);
5294 if Validity_Checks_On and then Validity_Check_Subscripts then
5295 Apply_Subscript_Validity_Checks (N);
5298 -- All done for the non-packed case
5300 if not Is_Packed (Etype (Prefix (N))) then
5304 -- For packed arrays that are not bit-packed (i.e. the case of an array
5305 -- with one or more index types with a non-contiguous enumeration type),
5306 -- we can always use the normal packed element get circuit.
5308 if not Is_Bit_Packed_Array (Etype (Prefix (N))) then
5309 Expand_Packed_Element_Reference (N);
5313 -- For a reference to a component of a bit packed array, we have to
5314 -- convert it to a reference to the corresponding Packed_Array_Type.
5315 -- We only want to do this for simple references, and not for:
5317 -- Left side of assignment, or prefix of left side of assignment, or
5318 -- prefix of the prefix, to handle packed arrays of packed arrays,
5319 -- This case is handled in Exp_Ch5.Expand_N_Assignment_Statement
5321 -- Renaming objects in renaming associations
5322 -- This case is handled when a use of the renamed variable occurs
5324 -- Actual parameters for a procedure call
5325 -- This case is handled in Exp_Ch6.Expand_Actuals
5327 -- The second expression in a 'Read attribute reference
5329 -- The prefix of an address or bit or size attribute reference
5331 -- The following circuit detects these exceptions
5334 Child : Node_Id := N;
5335 Parnt : Node_Id := Parent (N);
5339 if Nkind (Parnt) = N_Unchecked_Expression then
5342 elsif Nkind_In (Parnt, N_Object_Renaming_Declaration,
5343 N_Procedure_Call_Statement)
5344 or else (Nkind (Parnt) = N_Parameter_Association
5346 Nkind (Parent (Parnt)) = N_Procedure_Call_Statement)
5350 elsif Nkind (Parnt) = N_Attribute_Reference
5351 and then (Attribute_Name (Parnt) = Name_Address
5353 Attribute_Name (Parnt) = Name_Bit
5355 Attribute_Name (Parnt) = Name_Size)
5356 and then Prefix (Parnt) = Child
5360 elsif Nkind (Parnt) = N_Assignment_Statement
5361 and then Name (Parnt) = Child
5365 -- If the expression is an index of an indexed component, it must
5366 -- be expanded regardless of context.
5368 elsif Nkind (Parnt) = N_Indexed_Component
5369 and then Child /= Prefix (Parnt)
5371 Expand_Packed_Element_Reference (N);
5374 elsif Nkind (Parent (Parnt)) = N_Assignment_Statement
5375 and then Name (Parent (Parnt)) = Parnt
5379 elsif Nkind (Parnt) = N_Attribute_Reference
5380 and then Attribute_Name (Parnt) = Name_Read
5381 and then Next (First (Expressions (Parnt))) = Child
5385 elsif Nkind_In (Parnt, N_Indexed_Component, N_Selected_Component)
5386 and then Prefix (Parnt) = Child
5391 Expand_Packed_Element_Reference (N);
5395 -- Keep looking up tree for unchecked expression, or if we are the
5396 -- prefix of a possible assignment left side.
5399 Parnt := Parent (Child);
5402 end Expand_N_Indexed_Component;
5404 ---------------------
5405 -- Expand_N_Not_In --
5406 ---------------------
5408 -- Replace a not in b by not (a in b) so that the expansions for (a in b)
5409 -- can be done. This avoids needing to duplicate this expansion code.
5411 procedure Expand_N_Not_In (N : Node_Id) is
5412 Loc : constant Source_Ptr := Sloc (N);
5413 Typ : constant Entity_Id := Etype (N);
5414 Cfs : constant Boolean := Comes_From_Source (N);
5421 Left_Opnd => Left_Opnd (N),
5422 Right_Opnd => Right_Opnd (N))));
5424 -- If this is a set membership, preserve list of alternatives
5426 Set_Alternatives (Right_Opnd (N), Alternatives (Original_Node (N)));
5428 -- We want this to appear as coming from source if original does (see
5429 -- transformations in Expand_N_In).
5431 Set_Comes_From_Source (N, Cfs);
5432 Set_Comes_From_Source (Right_Opnd (N), Cfs);
5434 -- Now analyze transformed node
5436 Analyze_And_Resolve (N, Typ);
5437 end Expand_N_Not_In;
5443 -- The only replacement required is for the case of a null of a type that
5444 -- is an access to protected subprogram, or a subtype thereof. We represent
5445 -- such access values as a record, and so we must replace the occurrence of
5446 -- null by the equivalent record (with a null address and a null pointer in
5447 -- it), so that the backend creates the proper value.
5449 procedure Expand_N_Null (N : Node_Id) is
5450 Loc : constant Source_Ptr := Sloc (N);
5451 Typ : constant Entity_Id := Base_Type (Etype (N));
5455 if Is_Access_Protected_Subprogram_Type (Typ) then
5457 Make_Aggregate (Loc,
5458 Expressions => New_List (
5459 New_Occurrence_Of (RTE (RE_Null_Address), Loc),
5463 Analyze_And_Resolve (N, Equivalent_Type (Typ));
5465 -- For subsequent semantic analysis, the node must retain its type.
5466 -- Gigi in any case replaces this type by the corresponding record
5467 -- type before processing the node.
5473 when RE_Not_Available =>
5477 ---------------------
5478 -- Expand_N_Op_Abs --
5479 ---------------------
5481 procedure Expand_N_Op_Abs (N : Node_Id) is
5482 Loc : constant Source_Ptr := Sloc (N);
5483 Expr : constant Node_Id := Right_Opnd (N);
5486 Unary_Op_Validity_Checks (N);
5488 -- Deal with software overflow checking
5490 if not Backend_Overflow_Checks_On_Target
5491 and then Is_Signed_Integer_Type (Etype (N))
5492 and then Do_Overflow_Check (N)
5494 -- The only case to worry about is when the argument is equal to the
5495 -- largest negative number, so what we do is to insert the check:
5497 -- [constraint_error when Expr = typ'Base'First]
5499 -- with the usual Duplicate_Subexpr use coding for expr
5502 Make_Raise_Constraint_Error (Loc,
5505 Left_Opnd => Duplicate_Subexpr (Expr),
5507 Make_Attribute_Reference (Loc,
5509 New_Occurrence_Of (Base_Type (Etype (Expr)), Loc),
5510 Attribute_Name => Name_First)),
5511 Reason => CE_Overflow_Check_Failed));
5514 -- Vax floating-point types case
5516 if Vax_Float (Etype (N)) then
5517 Expand_Vax_Arith (N);
5519 end Expand_N_Op_Abs;
5521 ---------------------
5522 -- Expand_N_Op_Add --
5523 ---------------------
5525 procedure Expand_N_Op_Add (N : Node_Id) is
5526 Typ : constant Entity_Id := Etype (N);
5529 Binary_Op_Validity_Checks (N);
5531 -- N + 0 = 0 + N = N for integer types
5533 if Is_Integer_Type (Typ) then
5534 if Compile_Time_Known_Value (Right_Opnd (N))
5535 and then Expr_Value (Right_Opnd (N)) = Uint_0
5537 Rewrite (N, Left_Opnd (N));
5540 elsif Compile_Time_Known_Value (Left_Opnd (N))
5541 and then Expr_Value (Left_Opnd (N)) = Uint_0
5543 Rewrite (N, Right_Opnd (N));
5548 -- Arithmetic overflow checks for signed integer/fixed point types
5550 if Is_Signed_Integer_Type (Typ)
5551 or else Is_Fixed_Point_Type (Typ)
5553 Apply_Arithmetic_Overflow_Check (N);
5556 -- Vax floating-point types case
5558 elsif Vax_Float (Typ) then
5559 Expand_Vax_Arith (N);
5561 end Expand_N_Op_Add;
5563 ---------------------
5564 -- Expand_N_Op_And --
5565 ---------------------
5567 procedure Expand_N_Op_And (N : Node_Id) is
5568 Typ : constant Entity_Id := Etype (N);
5571 Binary_Op_Validity_Checks (N);
5573 if Is_Array_Type (Etype (N)) then
5574 Expand_Boolean_Operator (N);
5576 elsif Is_Boolean_Type (Etype (N)) then
5578 -- Replace AND by AND THEN if Short_Circuit_And_Or active and the
5579 -- type is standard Boolean (do not mess with AND that uses a non-
5580 -- standard Boolean type, because something strange is going on).
5582 if Short_Circuit_And_Or and then Typ = Standard_Boolean then
5584 Make_And_Then (Sloc (N),
5585 Left_Opnd => Relocate_Node (Left_Opnd (N)),
5586 Right_Opnd => Relocate_Node (Right_Opnd (N))));
5587 Analyze_And_Resolve (N, Typ);
5589 -- Otherwise, adjust conditions
5592 Adjust_Condition (Left_Opnd (N));
5593 Adjust_Condition (Right_Opnd (N));
5594 Set_Etype (N, Standard_Boolean);
5595 Adjust_Result_Type (N, Typ);
5598 elsif Is_Intrinsic_Subprogram (Entity (N)) then
5599 Expand_Intrinsic_Call (N, Entity (N));
5602 end Expand_N_Op_And;
5604 ------------------------
5605 -- Expand_N_Op_Concat --
5606 ------------------------
5608 procedure Expand_N_Op_Concat (N : Node_Id) is
5610 -- List of operands to be concatenated
5613 -- Node which is to be replaced by the result of concatenating the nodes
5614 -- in the list Opnds.
5617 -- Ensure validity of both operands
5619 Binary_Op_Validity_Checks (N);
5621 -- If we are the left operand of a concatenation higher up the tree,
5622 -- then do nothing for now, since we want to deal with a series of
5623 -- concatenations as a unit.
5625 if Nkind (Parent (N)) = N_Op_Concat
5626 and then N = Left_Opnd (Parent (N))
5631 -- We get here with a concatenation whose left operand may be a
5632 -- concatenation itself with a consistent type. We need to process
5633 -- these concatenation operands from left to right, which means
5634 -- from the deepest node in the tree to the highest node.
5637 while Nkind (Left_Opnd (Cnode)) = N_Op_Concat loop
5638 Cnode := Left_Opnd (Cnode);
5641 -- Now Cnode is the deepest concatenation, and its parents are the
5642 -- concatenation nodes above, so now we process bottom up, doing the
5643 -- operations. We gather a string that is as long as possible up to five
5646 -- The outer loop runs more than once if more than one concatenation
5647 -- type is involved.
5650 Opnds := New_List (Left_Opnd (Cnode), Right_Opnd (Cnode));
5651 Set_Parent (Opnds, N);
5653 -- The inner loop gathers concatenation operands
5655 Inner : while Cnode /= N
5656 and then Base_Type (Etype (Cnode)) =
5657 Base_Type (Etype (Parent (Cnode)))
5659 Cnode := Parent (Cnode);
5660 Append (Right_Opnd (Cnode), Opnds);
5663 Expand_Concatenate (Cnode, Opnds);
5665 exit Outer when Cnode = N;
5666 Cnode := Parent (Cnode);
5668 end Expand_N_Op_Concat;
5670 ------------------------
5671 -- Expand_N_Op_Divide --
5672 ------------------------
5674 procedure Expand_N_Op_Divide (N : Node_Id) is
5675 Loc : constant Source_Ptr := Sloc (N);
5676 Lopnd : constant Node_Id := Left_Opnd (N);
5677 Ropnd : constant Node_Id := Right_Opnd (N);
5678 Ltyp : constant Entity_Id := Etype (Lopnd);
5679 Rtyp : constant Entity_Id := Etype (Ropnd);
5680 Typ : Entity_Id := Etype (N);
5681 Rknow : constant Boolean := Is_Integer_Type (Typ)
5683 Compile_Time_Known_Value (Ropnd);
5687 Binary_Op_Validity_Checks (N);
5690 Rval := Expr_Value (Ropnd);
5693 -- N / 1 = N for integer types
5695 if Rknow and then Rval = Uint_1 then
5700 -- Convert x / 2 ** y to Shift_Right (x, y). Note that the fact that
5701 -- Is_Power_Of_2_For_Shift is set means that we know that our left
5702 -- operand is an unsigned integer, as required for this to work.
5704 if Nkind (Ropnd) = N_Op_Expon
5705 and then Is_Power_Of_2_For_Shift (Ropnd)
5707 -- We cannot do this transformation in configurable run time mode if we
5708 -- have 64-bit integers and long shifts are not available.
5712 or else Support_Long_Shifts_On_Target)
5715 Make_Op_Shift_Right (Loc,
5718 Convert_To (Standard_Natural, Right_Opnd (Ropnd))));
5719 Analyze_And_Resolve (N, Typ);
5723 -- Do required fixup of universal fixed operation
5725 if Typ = Universal_Fixed then
5726 Fixup_Universal_Fixed_Operation (N);
5730 -- Divisions with fixed-point results
5732 if Is_Fixed_Point_Type (Typ) then
5734 -- No special processing if Treat_Fixed_As_Integer is set, since
5735 -- from a semantic point of view such operations are simply integer
5736 -- operations and will be treated that way.
5738 if not Treat_Fixed_As_Integer (N) then
5739 if Is_Integer_Type (Rtyp) then
5740 Expand_Divide_Fixed_By_Integer_Giving_Fixed (N);
5742 Expand_Divide_Fixed_By_Fixed_Giving_Fixed (N);
5746 -- Other cases of division of fixed-point operands. Again we exclude the
5747 -- case where Treat_Fixed_As_Integer is set.
5749 elsif (Is_Fixed_Point_Type (Ltyp) or else
5750 Is_Fixed_Point_Type (Rtyp))
5751 and then not Treat_Fixed_As_Integer (N)
5753 if Is_Integer_Type (Typ) then
5754 Expand_Divide_Fixed_By_Fixed_Giving_Integer (N);
5756 pragma Assert (Is_Floating_Point_Type (Typ));
5757 Expand_Divide_Fixed_By_Fixed_Giving_Float (N);
5760 -- Mixed-mode operations can appear in a non-static universal context,
5761 -- in which case the integer argument must be converted explicitly.
5763 elsif Typ = Universal_Real
5764 and then Is_Integer_Type (Rtyp)
5767 Convert_To (Universal_Real, Relocate_Node (Ropnd)));
5769 Analyze_And_Resolve (Ropnd, Universal_Real);
5771 elsif Typ = Universal_Real
5772 and then Is_Integer_Type (Ltyp)
5775 Convert_To (Universal_Real, Relocate_Node (Lopnd)));
5777 Analyze_And_Resolve (Lopnd, Universal_Real);
5779 -- Non-fixed point cases, do integer zero divide and overflow checks
5781 elsif Is_Integer_Type (Typ) then
5782 Apply_Divide_Check (N);
5784 -- Deal with Vax_Float
5786 elsif Vax_Float (Typ) then
5787 Expand_Vax_Arith (N);
5790 end Expand_N_Op_Divide;
5792 --------------------
5793 -- Expand_N_Op_Eq --
5794 --------------------
5796 procedure Expand_N_Op_Eq (N : Node_Id) is
5797 Loc : constant Source_Ptr := Sloc (N);
5798 Typ : constant Entity_Id := Etype (N);
5799 Lhs : constant Node_Id := Left_Opnd (N);
5800 Rhs : constant Node_Id := Right_Opnd (N);
5801 Bodies : constant List_Id := New_List;
5802 A_Typ : constant Entity_Id := Etype (Lhs);
5804 Typl : Entity_Id := A_Typ;
5805 Op_Name : Entity_Id;
5808 procedure Build_Equality_Call (Eq : Entity_Id);
5809 -- If a constructed equality exists for the type or for its parent,
5810 -- build and analyze call, adding conversions if the operation is
5813 function Has_Unconstrained_UU_Component (Typ : Node_Id) return Boolean;
5814 -- Determines whether a type has a subcomponent of an unconstrained
5815 -- Unchecked_Union subtype. Typ is a record type.
5817 -------------------------
5818 -- Build_Equality_Call --
5819 -------------------------
5821 procedure Build_Equality_Call (Eq : Entity_Id) is
5822 Op_Type : constant Entity_Id := Etype (First_Formal (Eq));
5823 L_Exp : Node_Id := Relocate_Node (Lhs);
5824 R_Exp : Node_Id := Relocate_Node (Rhs);
5827 if Base_Type (Op_Type) /= Base_Type (A_Typ)
5828 and then not Is_Class_Wide_Type (A_Typ)
5830 L_Exp := OK_Convert_To (Op_Type, L_Exp);
5831 R_Exp := OK_Convert_To (Op_Type, R_Exp);
5834 -- If we have an Unchecked_Union, we need to add the inferred
5835 -- discriminant values as actuals in the function call. At this
5836 -- point, the expansion has determined that both operands have
5837 -- inferable discriminants.
5839 if Is_Unchecked_Union (Op_Type) then
5841 Lhs_Type : constant Node_Id := Etype (L_Exp);
5842 Rhs_Type : constant Node_Id := Etype (R_Exp);
5843 Lhs_Discr_Val : Node_Id;
5844 Rhs_Discr_Val : Node_Id;
5847 -- Per-object constrained selected components require special
5848 -- attention. If the enclosing scope of the component is an
5849 -- Unchecked_Union, we cannot reference its discriminants
5850 -- directly. This is why we use the two extra parameters of
5851 -- the equality function of the enclosing Unchecked_Union.
5853 -- type UU_Type (Discr : Integer := 0) is
5856 -- pragma Unchecked_Union (UU_Type);
5858 -- 1. Unchecked_Union enclosing record:
5860 -- type Enclosing_UU_Type (Discr : Integer := 0) is record
5862 -- Comp : UU_Type (Discr);
5864 -- end Enclosing_UU_Type;
5865 -- pragma Unchecked_Union (Enclosing_UU_Type);
5867 -- Obj1 : Enclosing_UU_Type;
5868 -- Obj2 : Enclosing_UU_Type (1);
5870 -- [. . .] Obj1 = Obj2 [. . .]
5874 -- if not (uu_typeEQ (obj1.comp, obj2.comp, a, b)) then
5876 -- A and B are the formal parameters of the equality function
5877 -- of Enclosing_UU_Type. The function always has two extra
5878 -- formals to capture the inferred discriminant values.
5880 -- 2. Non-Unchecked_Union enclosing record:
5883 -- Enclosing_Non_UU_Type (Discr : Integer := 0)
5886 -- Comp : UU_Type (Discr);
5888 -- end Enclosing_Non_UU_Type;
5890 -- Obj1 : Enclosing_Non_UU_Type;
5891 -- Obj2 : Enclosing_Non_UU_Type (1);
5893 -- ... Obj1 = Obj2 ...
5897 -- if not (uu_typeEQ (obj1.comp, obj2.comp,
5898 -- obj1.discr, obj2.discr)) then
5900 -- In this case we can directly reference the discriminants of
5901 -- the enclosing record.
5905 if Nkind (Lhs) = N_Selected_Component
5906 and then Has_Per_Object_Constraint
5907 (Entity (Selector_Name (Lhs)))
5909 -- Enclosing record is an Unchecked_Union, use formal A
5911 if Is_Unchecked_Union
5912 (Scope (Entity (Selector_Name (Lhs))))
5914 Lhs_Discr_Val := Make_Identifier (Loc, Name_A);
5916 -- Enclosing record is of a non-Unchecked_Union type, it is
5917 -- possible to reference the discriminant.
5921 Make_Selected_Component (Loc,
5922 Prefix => Prefix (Lhs),
5925 (Get_Discriminant_Value
5926 (First_Discriminant (Lhs_Type),
5928 Stored_Constraint (Lhs_Type))));
5931 -- Comment needed here ???
5934 -- Infer the discriminant value
5938 (Get_Discriminant_Value
5939 (First_Discriminant (Lhs_Type),
5941 Stored_Constraint (Lhs_Type)));
5946 if Nkind (Rhs) = N_Selected_Component
5947 and then Has_Per_Object_Constraint
5948 (Entity (Selector_Name (Rhs)))
5950 if Is_Unchecked_Union
5951 (Scope (Entity (Selector_Name (Rhs))))
5953 Rhs_Discr_Val := Make_Identifier (Loc, Name_B);
5957 Make_Selected_Component (Loc,
5958 Prefix => Prefix (Rhs),
5960 New_Copy (Get_Discriminant_Value (
5961 First_Discriminant (Rhs_Type),
5963 Stored_Constraint (Rhs_Type))));
5968 New_Copy (Get_Discriminant_Value (
5969 First_Discriminant (Rhs_Type),
5971 Stored_Constraint (Rhs_Type)));
5976 Make_Function_Call (Loc,
5977 Name => New_Reference_To (Eq, Loc),
5978 Parameter_Associations => New_List (
5985 -- Normal case, not an unchecked union
5989 Make_Function_Call (Loc,
5990 Name => New_Reference_To (Eq, Loc),
5991 Parameter_Associations => New_List (L_Exp, R_Exp)));
5994 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
5995 end Build_Equality_Call;
5997 ------------------------------------
5998 -- Has_Unconstrained_UU_Component --
5999 ------------------------------------
6001 function Has_Unconstrained_UU_Component
6002 (Typ : Node_Id) return Boolean
6004 Tdef : constant Node_Id :=
6005 Type_Definition (Declaration_Node (Base_Type (Typ)));
6009 function Component_Is_Unconstrained_UU
6010 (Comp : Node_Id) return Boolean;
6011 -- Determines whether the subtype of the component is an
6012 -- unconstrained Unchecked_Union.
6014 function Variant_Is_Unconstrained_UU
6015 (Variant : Node_Id) return Boolean;
6016 -- Determines whether a component of the variant has an unconstrained
6017 -- Unchecked_Union subtype.
6019 -----------------------------------
6020 -- Component_Is_Unconstrained_UU --
6021 -----------------------------------
6023 function Component_Is_Unconstrained_UU
6024 (Comp : Node_Id) return Boolean
6027 if Nkind (Comp) /= N_Component_Declaration then
6032 Sindic : constant Node_Id :=
6033 Subtype_Indication (Component_Definition (Comp));
6036 -- Unconstrained nominal type. In the case of a constraint
6037 -- present, the node kind would have been N_Subtype_Indication.
6039 if Nkind (Sindic) = N_Identifier then
6040 return Is_Unchecked_Union (Base_Type (Etype (Sindic)));
6045 end Component_Is_Unconstrained_UU;
6047 ---------------------------------
6048 -- Variant_Is_Unconstrained_UU --
6049 ---------------------------------
6051 function Variant_Is_Unconstrained_UU
6052 (Variant : Node_Id) return Boolean
6054 Clist : constant Node_Id := Component_List (Variant);
6057 if Is_Empty_List (Component_Items (Clist)) then
6061 -- We only need to test one component
6064 Comp : Node_Id := First (Component_Items (Clist));
6067 while Present (Comp) loop
6068 if Component_Is_Unconstrained_UU (Comp) then
6076 -- None of the components withing the variant were of
6077 -- unconstrained Unchecked_Union type.
6080 end Variant_Is_Unconstrained_UU;
6082 -- Start of processing for Has_Unconstrained_UU_Component
6085 if Null_Present (Tdef) then
6089 Clist := Component_List (Tdef);
6090 Vpart := Variant_Part (Clist);
6092 -- Inspect available components
6094 if Present (Component_Items (Clist)) then
6096 Comp : Node_Id := First (Component_Items (Clist));
6099 while Present (Comp) loop
6101 -- One component is sufficient
6103 if Component_Is_Unconstrained_UU (Comp) then
6112 -- Inspect available components withing variants
6114 if Present (Vpart) then
6116 Variant : Node_Id := First (Variants (Vpart));
6119 while Present (Variant) loop
6121 -- One component within a variant is sufficient
6123 if Variant_Is_Unconstrained_UU (Variant) then
6132 -- Neither the available components, nor the components inside the
6133 -- variant parts were of an unconstrained Unchecked_Union subtype.
6136 end Has_Unconstrained_UU_Component;
6138 -- Start of processing for Expand_N_Op_Eq
6141 Binary_Op_Validity_Checks (N);
6143 if Ekind (Typl) = E_Private_Type then
6144 Typl := Underlying_Type (Typl);
6145 elsif Ekind (Typl) = E_Private_Subtype then
6146 Typl := Underlying_Type (Base_Type (Typl));
6151 -- It may happen in error situations that the underlying type is not
6152 -- set. The error will be detected later, here we just defend the
6159 Typl := Base_Type (Typl);
6161 -- Boolean types (requiring handling of non-standard case)
6163 if Is_Boolean_Type (Typl) then
6164 Adjust_Condition (Left_Opnd (N));
6165 Adjust_Condition (Right_Opnd (N));
6166 Set_Etype (N, Standard_Boolean);
6167 Adjust_Result_Type (N, Typ);
6171 elsif Is_Array_Type (Typl) then
6173 -- If we are doing full validity checking, and it is possible for the
6174 -- array elements to be invalid then expand out array comparisons to
6175 -- make sure that we check the array elements.
6177 if Validity_Check_Operands
6178 and then not Is_Known_Valid (Component_Type (Typl))
6181 Save_Force_Validity_Checks : constant Boolean :=
6182 Force_Validity_Checks;
6184 Force_Validity_Checks := True;
6186 Expand_Array_Equality
6188 Relocate_Node (Lhs),
6189 Relocate_Node (Rhs),
6192 Insert_Actions (N, Bodies);
6193 Analyze_And_Resolve (N, Standard_Boolean);
6194 Force_Validity_Checks := Save_Force_Validity_Checks;
6197 -- Packed case where both operands are known aligned
6199 elsif Is_Bit_Packed_Array (Typl)
6200 and then not Is_Possibly_Unaligned_Object (Lhs)
6201 and then not Is_Possibly_Unaligned_Object (Rhs)
6203 Expand_Packed_Eq (N);
6205 -- Where the component type is elementary we can use a block bit
6206 -- comparison (if supported on the target) exception in the case
6207 -- of floating-point (negative zero issues require element by
6208 -- element comparison), and atomic types (where we must be sure
6209 -- to load elements independently) and possibly unaligned arrays.
6211 elsif Is_Elementary_Type (Component_Type (Typl))
6212 and then not Is_Floating_Point_Type (Component_Type (Typl))
6213 and then not Is_Atomic (Component_Type (Typl))
6214 and then not Is_Possibly_Unaligned_Object (Lhs)
6215 and then not Is_Possibly_Unaligned_Object (Rhs)
6216 and then Support_Composite_Compare_On_Target
6220 -- For composite and floating-point cases, expand equality loop to
6221 -- make sure of using proper comparisons for tagged types, and
6222 -- correctly handling the floating-point case.
6226 Expand_Array_Equality
6228 Relocate_Node (Lhs),
6229 Relocate_Node (Rhs),
6232 Insert_Actions (N, Bodies, Suppress => All_Checks);
6233 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
6238 elsif Is_Record_Type (Typl) then
6240 -- For tagged types, use the primitive "="
6242 if Is_Tagged_Type (Typl) then
6244 -- No need to do anything else compiling under restriction
6245 -- No_Dispatching_Calls. During the semantic analysis we
6246 -- already notified such violation.
6248 if Restriction_Active (No_Dispatching_Calls) then
6252 -- If this is derived from an untagged private type completed with
6253 -- a tagged type, it does not have a full view, so we use the
6254 -- primitive operations of the private type. This check should no
6255 -- longer be necessary when these types get their full views???
6257 if Is_Private_Type (A_Typ)
6258 and then not Is_Tagged_Type (A_Typ)
6259 and then Is_Derived_Type (A_Typ)
6260 and then No (Full_View (A_Typ))
6262 -- Search for equality operation, checking that the operands
6263 -- have the same type. Note that we must find a matching entry,
6264 -- or something is very wrong!
6266 Prim := First_Elmt (Collect_Primitive_Operations (A_Typ));
6268 while Present (Prim) loop
6269 exit when Chars (Node (Prim)) = Name_Op_Eq
6270 and then Etype (First_Formal (Node (Prim))) =
6271 Etype (Next_Formal (First_Formal (Node (Prim))))
6273 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
6278 pragma Assert (Present (Prim));
6279 Op_Name := Node (Prim);
6281 -- Find the type's predefined equality or an overriding
6282 -- user- defined equality. The reason for not simply calling
6283 -- Find_Prim_Op here is that there may be a user-defined
6284 -- overloaded equality op that precedes the equality that we want,
6285 -- so we have to explicitly search (e.g., there could be an
6286 -- equality with two different parameter types).
6289 if Is_Class_Wide_Type (Typl) then
6290 Typl := Root_Type (Typl);
6293 Prim := First_Elmt (Primitive_Operations (Typl));
6294 while Present (Prim) loop
6295 exit when Chars (Node (Prim)) = Name_Op_Eq
6296 and then Etype (First_Formal (Node (Prim))) =
6297 Etype (Next_Formal (First_Formal (Node (Prim))))
6299 Base_Type (Etype (Node (Prim))) = Standard_Boolean;
6304 pragma Assert (Present (Prim));
6305 Op_Name := Node (Prim);
6308 Build_Equality_Call (Op_Name);
6310 -- Ada 2005 (AI-216): Program_Error is raised when evaluating the
6311 -- predefined equality operator for a type which has a subcomponent
6312 -- of an Unchecked_Union type whose nominal subtype is unconstrained.
6314 elsif Has_Unconstrained_UU_Component (Typl) then
6316 Make_Raise_Program_Error (Loc,
6317 Reason => PE_Unchecked_Union_Restriction));
6319 -- Prevent Gigi from generating incorrect code by rewriting the
6320 -- equality as a standard False.
6323 New_Occurrence_Of (Standard_False, Loc));
6325 elsif Is_Unchecked_Union (Typl) then
6327 -- If we can infer the discriminants of the operands, we make a
6328 -- call to the TSS equality function.
6330 if Has_Inferable_Discriminants (Lhs)
6332 Has_Inferable_Discriminants (Rhs)
6335 (TSS (Root_Type (Typl), TSS_Composite_Equality));
6338 -- Ada 2005 (AI-216): Program_Error is raised when evaluating
6339 -- the predefined equality operator for an Unchecked_Union type
6340 -- if either of the operands lack inferable discriminants.
6343 Make_Raise_Program_Error (Loc,
6344 Reason => PE_Unchecked_Union_Restriction));
6346 -- Prevent Gigi from generating incorrect code by rewriting
6347 -- the equality as a standard False.
6350 New_Occurrence_Of (Standard_False, Loc));
6354 -- If a type support function is present (for complex cases), use it
6356 elsif Present (TSS (Root_Type (Typl), TSS_Composite_Equality)) then
6358 (TSS (Root_Type (Typl), TSS_Composite_Equality));
6360 -- Otherwise expand the component by component equality. Note that
6361 -- we never use block-bit comparisons for records, because of the
6362 -- problems with gaps. The backend will often be able to recombine
6363 -- the separate comparisons that we generate here.
6366 Remove_Side_Effects (Lhs);
6367 Remove_Side_Effects (Rhs);
6369 Expand_Record_Equality (N, Typl, Lhs, Rhs, Bodies));
6371 Insert_Actions (N, Bodies, Suppress => All_Checks);
6372 Analyze_And_Resolve (N, Standard_Boolean, Suppress => All_Checks);
6376 -- Test if result is known at compile time
6378 Rewrite_Comparison (N);
6380 -- If we still have comparison for Vax_Float, process it
6382 if Vax_Float (Typl) and then Nkind (N) in N_Op_Compare then
6383 Expand_Vax_Comparison (N);
6387 Optimize_Length_Comparison (N);
6390 -----------------------
6391 -- Expand_N_Op_Expon --
6392 -----------------------
6394 procedure Expand_N_Op_Expon (N : Node_Id) is
6395 Loc : constant Source_Ptr := Sloc (N);
6396 Typ : constant Entity_Id := Etype (N);
6397 Rtyp : constant Entity_Id := Root_Type (Typ);
6398 Base : constant Node_Id := Relocate_Node (Left_Opnd (N));
6399 Bastyp : constant Node_Id := Etype (Base);
6400 Exp : constant Node_Id := Relocate_Node (Right_Opnd (N));
6401 Exptyp : constant Entity_Id := Etype (Exp);
6402 Ovflo : constant Boolean := Do_Overflow_Check (N);
6411 Binary_Op_Validity_Checks (N);
6413 -- CodePeer and GNATprove want to see the unexpanded N_Op_Expon node
6415 if CodePeer_Mode or Alfa_Mode then
6419 -- If either operand is of a private type, then we have the use of an
6420 -- intrinsic operator, and we get rid of the privateness, by using root
6421 -- types of underlying types for the actual operation. Otherwise the
6422 -- private types will cause trouble if we expand multiplications or
6423 -- shifts etc. We also do this transformation if the result type is
6424 -- different from the base type.
6426 if Is_Private_Type (Etype (Base))
6427 or else Is_Private_Type (Typ)
6428 or else Is_Private_Type (Exptyp)
6429 or else Rtyp /= Root_Type (Bastyp)
6432 Bt : constant Entity_Id := Root_Type (Underlying_Type (Bastyp));
6433 Et : constant Entity_Id := Root_Type (Underlying_Type (Exptyp));
6437 Unchecked_Convert_To (Typ,
6439 Left_Opnd => Unchecked_Convert_To (Bt, Base),
6440 Right_Opnd => Unchecked_Convert_To (Et, Exp))));
6441 Analyze_And_Resolve (N, Typ);
6446 -- Test for case of known right argument
6448 if Compile_Time_Known_Value (Exp) then
6449 Expv := Expr_Value (Exp);
6451 -- We only fold small non-negative exponents. You might think we
6452 -- could fold small negative exponents for the real case, but we
6453 -- can't because we are required to raise Constraint_Error for
6454 -- the case of 0.0 ** (negative) even if Machine_Overflows = False.
6455 -- See ACVC test C4A012B.
6457 if Expv >= 0 and then Expv <= 4 then
6459 -- X ** 0 = 1 (or 1.0)
6463 -- Call Remove_Side_Effects to ensure that any side effects
6464 -- in the ignored left operand (in particular function calls
6465 -- to user defined functions) are properly executed.
6467 Remove_Side_Effects (Base);
6469 if Ekind (Typ) in Integer_Kind then
6470 Xnode := Make_Integer_Literal (Loc, Intval => 1);
6472 Xnode := Make_Real_Literal (Loc, Ureal_1);
6484 Make_Op_Multiply (Loc,
6485 Left_Opnd => Duplicate_Subexpr (Base),
6486 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
6488 -- X ** 3 = X * X * X
6492 Make_Op_Multiply (Loc,
6494 Make_Op_Multiply (Loc,
6495 Left_Opnd => Duplicate_Subexpr (Base),
6496 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)),
6497 Right_Opnd => Duplicate_Subexpr_No_Checks (Base));
6500 -- En : constant base'type := base * base;
6505 Temp := Make_Temporary (Loc, 'E', Base);
6507 Insert_Actions (N, New_List (
6508 Make_Object_Declaration (Loc,
6509 Defining_Identifier => Temp,
6510 Constant_Present => True,
6511 Object_Definition => New_Reference_To (Typ, Loc),
6513 Make_Op_Multiply (Loc,
6514 Left_Opnd => Duplicate_Subexpr (Base),
6515 Right_Opnd => Duplicate_Subexpr_No_Checks (Base)))));
6518 Make_Op_Multiply (Loc,
6519 Left_Opnd => New_Reference_To (Temp, Loc),
6520 Right_Opnd => New_Reference_To (Temp, Loc));
6524 Analyze_And_Resolve (N, Typ);
6529 -- Case of (2 ** expression) appearing as an argument of an integer
6530 -- multiplication, or as the right argument of a division of a non-
6531 -- negative integer. In such cases we leave the node untouched, setting
6532 -- the flag Is_Natural_Power_Of_2_for_Shift set, then the expansion
6533 -- of the higher level node converts it into a shift.
6535 -- Another case is 2 ** N in any other context. We simply convert
6536 -- this to 1 * 2 ** N, and then the above transformation applies.
6538 -- Note: this transformation is not applicable for a modular type with
6539 -- a non-binary modulus in the multiplication case, since we get a wrong
6540 -- result if the shift causes an overflow before the modular reduction.
6542 if Nkind (Base) = N_Integer_Literal
6543 and then Intval (Base) = 2
6544 and then Is_Integer_Type (Root_Type (Exptyp))
6545 and then Esize (Root_Type (Exptyp)) <= Esize (Standard_Integer)
6546 and then Is_Unsigned_Type (Exptyp)
6549 -- First the multiply and divide cases
6551 if Nkind_In (Parent (N), N_Op_Divide, N_Op_Multiply) then
6553 P : constant Node_Id := Parent (N);
6554 L : constant Node_Id := Left_Opnd (P);
6555 R : constant Node_Id := Right_Opnd (P);
6558 if (Nkind (P) = N_Op_Multiply
6559 and then not Non_Binary_Modulus (Typ)
6561 ((Is_Integer_Type (Etype (L)) and then R = N)
6563 (Is_Integer_Type (Etype (R)) and then L = N))
6564 and then not Do_Overflow_Check (P))
6566 (Nkind (P) = N_Op_Divide
6567 and then Is_Integer_Type (Etype (L))
6568 and then Is_Unsigned_Type (Etype (L))
6570 and then not Do_Overflow_Check (P))
6572 Set_Is_Power_Of_2_For_Shift (N);
6577 -- Now the other cases
6579 elsif not Non_Binary_Modulus (Typ) then
6581 Make_Op_Multiply (Loc,
6582 Left_Opnd => Make_Integer_Literal (Loc, 1),
6583 Right_Opnd => Relocate_Node (N)));
6584 Analyze_And_Resolve (N, Typ);
6589 -- Fall through if exponentiation must be done using a runtime routine
6591 -- First deal with modular case
6593 if Is_Modular_Integer_Type (Rtyp) then
6595 -- Non-binary case, we call the special exponentiation routine for
6596 -- the non-binary case, converting the argument to Long_Long_Integer
6597 -- and passing the modulus value. Then the result is converted back
6598 -- to the base type.
6600 if Non_Binary_Modulus (Rtyp) then
6603 Make_Function_Call (Loc,
6604 Name => New_Reference_To (RTE (RE_Exp_Modular), Loc),
6605 Parameter_Associations => New_List (
6606 Convert_To (Standard_Integer, Base),
6607 Make_Integer_Literal (Loc, Modulus (Rtyp)),
6610 -- Binary case, in this case, we call one of two routines, either the
6611 -- unsigned integer case, or the unsigned long long integer case,
6612 -- with a final "and" operation to do the required mod.
6615 if UI_To_Int (Esize (Rtyp)) <= Standard_Integer_Size then
6616 Ent := RTE (RE_Exp_Unsigned);
6618 Ent := RTE (RE_Exp_Long_Long_Unsigned);
6625 Make_Function_Call (Loc,
6626 Name => New_Reference_To (Ent, Loc),
6627 Parameter_Associations => New_List (
6628 Convert_To (Etype (First_Formal (Ent)), Base),
6631 Make_Integer_Literal (Loc, Modulus (Rtyp) - 1))));
6635 -- Common exit point for modular type case
6637 Analyze_And_Resolve (N, Typ);
6640 -- Signed integer cases, done using either Integer or Long_Long_Integer.
6641 -- It is not worth having routines for Short_[Short_]Integer, since for
6642 -- most machines it would not help, and it would generate more code that
6643 -- might need certification when a certified run time is required.
6645 -- In the integer cases, we have two routines, one for when overflow
6646 -- checks are required, and one when they are not required, since there
6647 -- is a real gain in omitting checks on many machines.
6649 elsif Rtyp = Base_Type (Standard_Long_Long_Integer)
6650 or else (Rtyp = Base_Type (Standard_Long_Integer)
6652 Esize (Standard_Long_Integer) > Esize (Standard_Integer))
6653 or else (Rtyp = Universal_Integer)
6655 Etyp := Standard_Long_Long_Integer;
6658 Rent := RE_Exp_Long_Long_Integer;
6660 Rent := RE_Exn_Long_Long_Integer;
6663 elsif Is_Signed_Integer_Type (Rtyp) then
6664 Etyp := Standard_Integer;
6667 Rent := RE_Exp_Integer;
6669 Rent := RE_Exn_Integer;
6672 -- Floating-point cases, always done using Long_Long_Float. We do not
6673 -- need separate routines for the overflow case here, since in the case
6674 -- of floating-point, we generate infinities anyway as a rule (either
6675 -- that or we automatically trap overflow), and if there is an infinity
6676 -- generated and a range check is required, the check will fail anyway.
6679 pragma Assert (Is_Floating_Point_Type (Rtyp));
6680 Etyp := Standard_Long_Long_Float;
6681 Rent := RE_Exn_Long_Long_Float;
6684 -- Common processing for integer cases and floating-point cases.
6685 -- If we are in the right type, we can call runtime routine directly
6688 and then Rtyp /= Universal_Integer
6689 and then Rtyp /= Universal_Real
6692 Make_Function_Call (Loc,
6693 Name => New_Reference_To (RTE (Rent), Loc),
6694 Parameter_Associations => New_List (Base, Exp)));
6696 -- Otherwise we have to introduce conversions (conversions are also
6697 -- required in the universal cases, since the runtime routine is
6698 -- typed using one of the standard types).
6703 Make_Function_Call (Loc,
6704 Name => New_Reference_To (RTE (Rent), Loc),
6705 Parameter_Associations => New_List (
6706 Convert_To (Etyp, Base),
6710 Analyze_And_Resolve (N, Typ);
6714 when RE_Not_Available =>
6716 end Expand_N_Op_Expon;
6718 --------------------
6719 -- Expand_N_Op_Ge --
6720 --------------------
6722 procedure Expand_N_Op_Ge (N : Node_Id) is
6723 Typ : constant Entity_Id := Etype (N);
6724 Op1 : constant Node_Id := Left_Opnd (N);
6725 Op2 : constant Node_Id := Right_Opnd (N);
6726 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6729 Binary_Op_Validity_Checks (N);
6731 if Is_Array_Type (Typ1) then
6732 Expand_Array_Comparison (N);
6736 if Is_Boolean_Type (Typ1) then
6737 Adjust_Condition (Op1);
6738 Adjust_Condition (Op2);
6739 Set_Etype (N, Standard_Boolean);
6740 Adjust_Result_Type (N, Typ);
6743 Rewrite_Comparison (N);
6745 -- If we still have comparison, and Vax_Float type, process it
6747 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6748 Expand_Vax_Comparison (N);
6752 Optimize_Length_Comparison (N);
6755 --------------------
6756 -- Expand_N_Op_Gt --
6757 --------------------
6759 procedure Expand_N_Op_Gt (N : Node_Id) is
6760 Typ : constant Entity_Id := Etype (N);
6761 Op1 : constant Node_Id := Left_Opnd (N);
6762 Op2 : constant Node_Id := Right_Opnd (N);
6763 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6766 Binary_Op_Validity_Checks (N);
6768 if Is_Array_Type (Typ1) then
6769 Expand_Array_Comparison (N);
6773 if Is_Boolean_Type (Typ1) then
6774 Adjust_Condition (Op1);
6775 Adjust_Condition (Op2);
6776 Set_Etype (N, Standard_Boolean);
6777 Adjust_Result_Type (N, Typ);
6780 Rewrite_Comparison (N);
6782 -- If we still have comparison, and Vax_Float type, process it
6784 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6785 Expand_Vax_Comparison (N);
6789 Optimize_Length_Comparison (N);
6792 --------------------
6793 -- Expand_N_Op_Le --
6794 --------------------
6796 procedure Expand_N_Op_Le (N : Node_Id) is
6797 Typ : constant Entity_Id := Etype (N);
6798 Op1 : constant Node_Id := Left_Opnd (N);
6799 Op2 : constant Node_Id := Right_Opnd (N);
6800 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6803 Binary_Op_Validity_Checks (N);
6805 if Is_Array_Type (Typ1) then
6806 Expand_Array_Comparison (N);
6810 if Is_Boolean_Type (Typ1) then
6811 Adjust_Condition (Op1);
6812 Adjust_Condition (Op2);
6813 Set_Etype (N, Standard_Boolean);
6814 Adjust_Result_Type (N, Typ);
6817 Rewrite_Comparison (N);
6819 -- If we still have comparison, and Vax_Float type, process it
6821 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6822 Expand_Vax_Comparison (N);
6826 Optimize_Length_Comparison (N);
6829 --------------------
6830 -- Expand_N_Op_Lt --
6831 --------------------
6833 procedure Expand_N_Op_Lt (N : Node_Id) is
6834 Typ : constant Entity_Id := Etype (N);
6835 Op1 : constant Node_Id := Left_Opnd (N);
6836 Op2 : constant Node_Id := Right_Opnd (N);
6837 Typ1 : constant Entity_Id := Base_Type (Etype (Op1));
6840 Binary_Op_Validity_Checks (N);
6842 if Is_Array_Type (Typ1) then
6843 Expand_Array_Comparison (N);
6847 if Is_Boolean_Type (Typ1) then
6848 Adjust_Condition (Op1);
6849 Adjust_Condition (Op2);
6850 Set_Etype (N, Standard_Boolean);
6851 Adjust_Result_Type (N, Typ);
6854 Rewrite_Comparison (N);
6856 -- If we still have comparison, and Vax_Float type, process it
6858 if Vax_Float (Typ1) and then Nkind (N) in N_Op_Compare then
6859 Expand_Vax_Comparison (N);
6863 Optimize_Length_Comparison (N);
6866 -----------------------
6867 -- Expand_N_Op_Minus --
6868 -----------------------
6870 procedure Expand_N_Op_Minus (N : Node_Id) is
6871 Loc : constant Source_Ptr := Sloc (N);
6872 Typ : constant Entity_Id := Etype (N);
6875 Unary_Op_Validity_Checks (N);
6877 if not Backend_Overflow_Checks_On_Target
6878 and then Is_Signed_Integer_Type (Etype (N))
6879 and then Do_Overflow_Check (N)
6881 -- Software overflow checking expands -expr into (0 - expr)
6884 Make_Op_Subtract (Loc,
6885 Left_Opnd => Make_Integer_Literal (Loc, 0),
6886 Right_Opnd => Right_Opnd (N)));
6888 Analyze_And_Resolve (N, Typ);
6890 -- Vax floating-point types case
6892 elsif Vax_Float (Etype (N)) then
6893 Expand_Vax_Arith (N);
6895 end Expand_N_Op_Minus;
6897 ---------------------
6898 -- Expand_N_Op_Mod --
6899 ---------------------
6901 procedure Expand_N_Op_Mod (N : Node_Id) is
6902 Loc : constant Source_Ptr := Sloc (N);
6903 Typ : constant Entity_Id := Etype (N);
6904 Left : constant Node_Id := Left_Opnd (N);
6905 Right : constant Node_Id := Right_Opnd (N);
6906 DOC : constant Boolean := Do_Overflow_Check (N);
6907 DDC : constant Boolean := Do_Division_Check (N);
6917 pragma Warnings (Off, Lhi);
6920 Binary_Op_Validity_Checks (N);
6922 Determine_Range (Right, ROK, Rlo, Rhi, Assume_Valid => True);
6923 Determine_Range (Left, LOK, Llo, Lhi, Assume_Valid => True);
6925 -- Convert mod to rem if operands are known non-negative. We do this
6926 -- since it is quite likely that this will improve the quality of code,
6927 -- (the operation now corresponds to the hardware remainder), and it
6928 -- does not seem likely that it could be harmful.
6930 if LOK and then Llo >= 0
6932 ROK and then Rlo >= 0
6935 Make_Op_Rem (Sloc (N),
6936 Left_Opnd => Left_Opnd (N),
6937 Right_Opnd => Right_Opnd (N)));
6939 -- Instead of reanalyzing the node we do the analysis manually. This
6940 -- avoids anomalies when the replacement is done in an instance and
6941 -- is epsilon more efficient.
6943 Set_Entity (N, Standard_Entity (S_Op_Rem));
6945 Set_Do_Overflow_Check (N, DOC);
6946 Set_Do_Division_Check (N, DDC);
6947 Expand_N_Op_Rem (N);
6950 -- Otherwise, normal mod processing
6953 if Is_Integer_Type (Etype (N)) then
6954 Apply_Divide_Check (N);
6957 -- Apply optimization x mod 1 = 0. We don't really need that with
6958 -- gcc, but it is useful with other back ends (e.g. AAMP), and is
6959 -- certainly harmless.
6961 if Is_Integer_Type (Etype (N))
6962 and then Compile_Time_Known_Value (Right)
6963 and then Expr_Value (Right) = Uint_1
6965 -- Call Remove_Side_Effects to ensure that any side effects in
6966 -- the ignored left operand (in particular function calls to
6967 -- user defined functions) are properly executed.
6969 Remove_Side_Effects (Left);
6971 Rewrite (N, Make_Integer_Literal (Loc, 0));
6972 Analyze_And_Resolve (N, Typ);
6976 -- Deal with annoying case of largest negative number remainder
6977 -- minus one. Gigi does not handle this case correctly, because
6978 -- it generates a divide instruction which may trap in this case.
6980 -- In fact the check is quite easy, if the right operand is -1, then
6981 -- the mod value is always 0, and we can just ignore the left operand
6982 -- completely in this case.
6984 -- The operand type may be private (e.g. in the expansion of an
6985 -- intrinsic operation) so we must use the underlying type to get the
6986 -- bounds, and convert the literals explicitly.
6990 (Type_Low_Bound (Base_Type (Underlying_Type (Etype (Left)))));
6992 if ((not ROK) or else (Rlo <= (-1) and then (-1) <= Rhi))
6994 ((not LOK) or else (Llo = LLB))
6997 Make_Conditional_Expression (Loc,
6998 Expressions => New_List (
7000 Left_Opnd => Duplicate_Subexpr (Right),
7002 Unchecked_Convert_To (Typ,
7003 Make_Integer_Literal (Loc, -1))),
7004 Unchecked_Convert_To (Typ,
7005 Make_Integer_Literal (Loc, Uint_0)),
7006 Relocate_Node (N))));
7008 Set_Analyzed (Next (Next (First (Expressions (N)))));
7009 Analyze_And_Resolve (N, Typ);
7012 end Expand_N_Op_Mod;
7014 --------------------------
7015 -- Expand_N_Op_Multiply --
7016 --------------------------
7018 procedure Expand_N_Op_Multiply (N : Node_Id) is
7019 Loc : constant Source_Ptr := Sloc (N);
7020 Lop : constant Node_Id := Left_Opnd (N);
7021 Rop : constant Node_Id := Right_Opnd (N);
7023 Lp2 : constant Boolean :=
7024 Nkind (Lop) = N_Op_Expon
7025 and then Is_Power_Of_2_For_Shift (Lop);
7027 Rp2 : constant Boolean :=
7028 Nkind (Rop) = N_Op_Expon
7029 and then Is_Power_Of_2_For_Shift (Rop);
7031 Ltyp : constant Entity_Id := Etype (Lop);
7032 Rtyp : constant Entity_Id := Etype (Rop);
7033 Typ : Entity_Id := Etype (N);
7036 Binary_Op_Validity_Checks (N);
7038 -- Special optimizations for integer types
7040 if Is_Integer_Type (Typ) then
7042 -- N * 0 = 0 for integer types
7044 if Compile_Time_Known_Value (Rop)
7045 and then Expr_Value (Rop) = Uint_0
7047 -- Call Remove_Side_Effects to ensure that any side effects in
7048 -- the ignored left operand (in particular function calls to
7049 -- user defined functions) are properly executed.
7051 Remove_Side_Effects (Lop);
7053 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
7054 Analyze_And_Resolve (N, Typ);
7058 -- Similar handling for 0 * N = 0
7060 if Compile_Time_Known_Value (Lop)
7061 and then Expr_Value (Lop) = Uint_0
7063 Remove_Side_Effects (Rop);
7064 Rewrite (N, Make_Integer_Literal (Loc, Uint_0));
7065 Analyze_And_Resolve (N, Typ);
7069 -- N * 1 = 1 * N = N for integer types
7071 -- This optimisation is not done if we are going to
7072 -- rewrite the product 1 * 2 ** N to a shift.
7074 if Compile_Time_Known_Value (Rop)
7075 and then Expr_Value (Rop) = Uint_1
7081 elsif Compile_Time_Known_Value (Lop)
7082 and then Expr_Value (Lop) = Uint_1
7090 -- Convert x * 2 ** y to Shift_Left (x, y). Note that the fact that
7091 -- Is_Power_Of_2_For_Shift is set means that we know that our left
7092 -- operand is an integer, as required for this to work.
7097 -- Convert 2 ** A * 2 ** B into 2 ** (A + B)
7101 Left_Opnd => Make_Integer_Literal (Loc, 2),
7104 Left_Opnd => Right_Opnd (Lop),
7105 Right_Opnd => Right_Opnd (Rop))));
7106 Analyze_And_Resolve (N, Typ);
7111 Make_Op_Shift_Left (Loc,
7114 Convert_To (Standard_Natural, Right_Opnd (Rop))));
7115 Analyze_And_Resolve (N, Typ);
7119 -- Same processing for the operands the other way round
7123 Make_Op_Shift_Left (Loc,
7126 Convert_To (Standard_Natural, Right_Opnd (Lop))));
7127 Analyze_And_Resolve (N, Typ);
7131 -- Do required fixup of universal fixed operation
7133 if Typ = Universal_Fixed then
7134 Fixup_Universal_Fixed_Operation (N);
7138 -- Multiplications with fixed-point results
7140 if Is_Fixed_Point_Type (Typ) then
7142 -- No special processing if Treat_Fixed_As_Integer is set, since from
7143 -- a semantic point of view such operations are simply integer
7144 -- operations and will be treated that way.
7146 if not Treat_Fixed_As_Integer (N) then
7148 -- Case of fixed * integer => fixed
7150 if Is_Integer_Type (Rtyp) then
7151 Expand_Multiply_Fixed_By_Integer_Giving_Fixed (N);
7153 -- Case of integer * fixed => fixed
7155 elsif Is_Integer_Type (Ltyp) then
7156 Expand_Multiply_Integer_By_Fixed_Giving_Fixed (N);
7158 -- Case of fixed * fixed => fixed
7161 Expand_Multiply_Fixed_By_Fixed_Giving_Fixed (N);
7165 -- Other cases of multiplication of fixed-point operands. Again we
7166 -- exclude the cases where Treat_Fixed_As_Integer flag is set.
7168 elsif (Is_Fixed_Point_Type (Ltyp) or else Is_Fixed_Point_Type (Rtyp))
7169 and then not Treat_Fixed_As_Integer (N)
7171 if Is_Integer_Type (Typ) then
7172 Expand_Multiply_Fixed_By_Fixed_Giving_Integer (N);
7174 pragma Assert (Is_Floating_Point_Type (Typ));
7175 Expand_Multiply_Fixed_By_Fixed_Giving_Float (N);
7178 -- Mixed-mode operations can appear in a non-static universal context,
7179 -- in which case the integer argument must be converted explicitly.
7181 elsif Typ = Universal_Real
7182 and then Is_Integer_Type (Rtyp)
7184 Rewrite (Rop, Convert_To (Universal_Real, Relocate_Node (Rop)));
7186 Analyze_And_Resolve (Rop, Universal_Real);
7188 elsif Typ = Universal_Real
7189 and then Is_Integer_Type (Ltyp)
7191 Rewrite (Lop, Convert_To (Universal_Real, Relocate_Node (Lop)));
7193 Analyze_And_Resolve (Lop, Universal_Real);
7195 -- Non-fixed point cases, check software overflow checking required
7197 elsif Is_Signed_Integer_Type (Etype (N)) then
7198 Apply_Arithmetic_Overflow_Check (N);
7200 -- Deal with VAX float case
7202 elsif Vax_Float (Typ) then
7203 Expand_Vax_Arith (N);
7206 end Expand_N_Op_Multiply;
7208 --------------------
7209 -- Expand_N_Op_Ne --
7210 --------------------
7212 procedure Expand_N_Op_Ne (N : Node_Id) is
7213 Typ : constant Entity_Id := Etype (Left_Opnd (N));
7216 -- Case of elementary type with standard operator
7218 if Is_Elementary_Type (Typ)
7219 and then Sloc (Entity (N)) = Standard_Location
7221 Binary_Op_Validity_Checks (N);
7223 -- Boolean types (requiring handling of non-standard case)
7225 if Is_Boolean_Type (Typ) then
7226 Adjust_Condition (Left_Opnd (N));
7227 Adjust_Condition (Right_Opnd (N));
7228 Set_Etype (N, Standard_Boolean);
7229 Adjust_Result_Type (N, Typ);
7232 Rewrite_Comparison (N);
7234 -- If we still have comparison for Vax_Float, process it
7236 if Vax_Float (Typ) and then Nkind (N) in N_Op_Compare then
7237 Expand_Vax_Comparison (N);
7241 -- For all cases other than elementary types, we rewrite node as the
7242 -- negation of an equality operation, and reanalyze. The equality to be
7243 -- used is defined in the same scope and has the same signature. This
7244 -- signature must be set explicitly since in an instance it may not have
7245 -- the same visibility as in the generic unit. This avoids duplicating
7246 -- or factoring the complex code for record/array equality tests etc.
7250 Loc : constant Source_Ptr := Sloc (N);
7252 Ne : constant Entity_Id := Entity (N);
7255 Binary_Op_Validity_Checks (N);
7261 Left_Opnd => Left_Opnd (N),
7262 Right_Opnd => Right_Opnd (N)));
7263 Set_Paren_Count (Right_Opnd (Neg), 1);
7265 if Scope (Ne) /= Standard_Standard then
7266 Set_Entity (Right_Opnd (Neg), Corresponding_Equality (Ne));
7269 -- For navigation purposes, we want to treat the inequality as an
7270 -- implicit reference to the corresponding equality. Preserve the
7271 -- Comes_From_ source flag to generate proper Xref entries.
7273 Preserve_Comes_From_Source (Neg, N);
7274 Preserve_Comes_From_Source (Right_Opnd (Neg), N);
7276 Analyze_And_Resolve (N, Standard_Boolean);
7280 Optimize_Length_Comparison (N);
7283 ---------------------
7284 -- Expand_N_Op_Not --
7285 ---------------------
7287 -- If the argument is other than a Boolean array type, there is no special
7288 -- expansion required, except for VMS operations on signed integers.
7290 -- For the packed case, we call the special routine in Exp_Pakd, except
7291 -- that if the component size is greater than one, we use the standard
7292 -- routine generating a gruesome loop (it is so peculiar to have packed
7293 -- arrays with non-standard Boolean representations anyway, so it does not
7294 -- matter that we do not handle this case efficiently).
7296 -- For the unpacked case (and for the special packed case where we have non
7297 -- standard Booleans, as discussed above), we generate and insert into the
7298 -- tree the following function definition:
7300 -- function Nnnn (A : arr) is
7303 -- for J in a'range loop
7304 -- B (J) := not A (J);
7309 -- Here arr is the actual subtype of the parameter (and hence always
7310 -- constrained). Then we replace the not with a call to this function.
7312 procedure Expand_N_Op_Not (N : Node_Id) is
7313 Loc : constant Source_Ptr := Sloc (N);
7314 Typ : constant Entity_Id := Etype (N);
7323 Func_Name : Entity_Id;
7324 Loop_Statement : Node_Id;
7327 Unary_Op_Validity_Checks (N);
7329 -- For boolean operand, deal with non-standard booleans
7331 if Is_Boolean_Type (Typ) then
7332 Adjust_Condition (Right_Opnd (N));
7333 Set_Etype (N, Standard_Boolean);
7334 Adjust_Result_Type (N, Typ);
7338 -- For the VMS "not" on signed integer types, use conversion to and from
7339 -- a predefined modular type.
7341 if Is_VMS_Operator (Entity (N)) then
7347 -- If this is a derived type, retrieve original VMS type so that
7348 -- the proper sized type is used for intermediate values.
7350 if Is_Derived_Type (Typ) then
7351 Rtyp := First_Subtype (Etype (Typ));
7356 -- The proper unsigned type must have a size compatible with the
7357 -- operand, to prevent misalignment.
7359 if RM_Size (Rtyp) <= 8 then
7360 Utyp := RTE (RE_Unsigned_8);
7362 elsif RM_Size (Rtyp) <= 16 then
7363 Utyp := RTE (RE_Unsigned_16);
7365 elsif RM_Size (Rtyp) = RM_Size (Standard_Unsigned) then
7366 Utyp := RTE (RE_Unsigned_32);
7369 Utyp := RTE (RE_Long_Long_Unsigned);
7373 Unchecked_Convert_To (Typ,
7375 Unchecked_Convert_To (Utyp, Right_Opnd (N)))));
7376 Analyze_And_Resolve (N, Typ);
7381 -- Only array types need any other processing
7383 if not Is_Array_Type (Typ) then
7387 -- Case of array operand. If bit packed with a component size of 1,
7388 -- handle it in Exp_Pakd if the operand is known to be aligned.
7390 if Is_Bit_Packed_Array (Typ)
7391 and then Component_Size (Typ) = 1
7392 and then not Is_Possibly_Unaligned_Object (Right_Opnd (N))
7394 Expand_Packed_Not (N);
7398 -- Case of array operand which is not bit-packed. If the context is
7399 -- a safe assignment, call in-place operation, If context is a larger
7400 -- boolean expression in the context of a safe assignment, expansion is
7401 -- done by enclosing operation.
7403 Opnd := Relocate_Node (Right_Opnd (N));
7404 Convert_To_Actual_Subtype (Opnd);
7405 Arr := Etype (Opnd);
7406 Ensure_Defined (Arr, N);
7407 Silly_Boolean_Array_Not_Test (N, Arr);
7409 if Nkind (Parent (N)) = N_Assignment_Statement then
7410 if Safe_In_Place_Array_Op (Name (Parent (N)), N, Empty) then
7411 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
7414 -- Special case the negation of a binary operation
7416 elsif Nkind_In (Opnd, N_Op_And, N_Op_Or, N_Op_Xor)
7417 and then Safe_In_Place_Array_Op
7418 (Name (Parent (N)), Left_Opnd (Opnd), Right_Opnd (Opnd))
7420 Build_Boolean_Array_Proc_Call (Parent (N), Opnd, Empty);
7424 elsif Nkind (Parent (N)) in N_Binary_Op
7425 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
7428 Op1 : constant Node_Id := Left_Opnd (Parent (N));
7429 Op2 : constant Node_Id := Right_Opnd (Parent (N));
7430 Lhs : constant Node_Id := Name (Parent (Parent (N)));
7433 if Safe_In_Place_Array_Op (Lhs, Op1, Op2) then
7435 -- (not A) op (not B) can be reduced to a single call
7437 if N = Op1 and then Nkind (Op2) = N_Op_Not then
7440 elsif N = Op2 and then Nkind (Op1) = N_Op_Not then
7443 -- A xor (not B) can also be special-cased
7445 elsif N = Op2 and then Nkind (Parent (N)) = N_Op_Xor then
7452 A := Make_Defining_Identifier (Loc, Name_uA);
7453 B := Make_Defining_Identifier (Loc, Name_uB);
7454 J := Make_Defining_Identifier (Loc, Name_uJ);
7457 Make_Indexed_Component (Loc,
7458 Prefix => New_Reference_To (A, Loc),
7459 Expressions => New_List (New_Reference_To (J, Loc)));
7462 Make_Indexed_Component (Loc,
7463 Prefix => New_Reference_To (B, Loc),
7464 Expressions => New_List (New_Reference_To (J, Loc)));
7467 Make_Implicit_Loop_Statement (N,
7468 Identifier => Empty,
7471 Make_Iteration_Scheme (Loc,
7472 Loop_Parameter_Specification =>
7473 Make_Loop_Parameter_Specification (Loc,
7474 Defining_Identifier => J,
7475 Discrete_Subtype_Definition =>
7476 Make_Attribute_Reference (Loc,
7477 Prefix => Make_Identifier (Loc, Chars (A)),
7478 Attribute_Name => Name_Range))),
7480 Statements => New_List (
7481 Make_Assignment_Statement (Loc,
7483 Expression => Make_Op_Not (Loc, A_J))));
7485 Func_Name := Make_Temporary (Loc, 'N');
7486 Set_Is_Inlined (Func_Name);
7489 Make_Subprogram_Body (Loc,
7491 Make_Function_Specification (Loc,
7492 Defining_Unit_Name => Func_Name,
7493 Parameter_Specifications => New_List (
7494 Make_Parameter_Specification (Loc,
7495 Defining_Identifier => A,
7496 Parameter_Type => New_Reference_To (Typ, Loc))),
7497 Result_Definition => New_Reference_To (Typ, Loc)),
7499 Declarations => New_List (
7500 Make_Object_Declaration (Loc,
7501 Defining_Identifier => B,
7502 Object_Definition => New_Reference_To (Arr, Loc))),
7504 Handled_Statement_Sequence =>
7505 Make_Handled_Sequence_Of_Statements (Loc,
7506 Statements => New_List (
7508 Make_Simple_Return_Statement (Loc,
7509 Expression => Make_Identifier (Loc, Chars (B)))))));
7512 Make_Function_Call (Loc,
7513 Name => New_Reference_To (Func_Name, Loc),
7514 Parameter_Associations => New_List (Opnd)));
7516 Analyze_And_Resolve (N, Typ);
7517 end Expand_N_Op_Not;
7519 --------------------
7520 -- Expand_N_Op_Or --
7521 --------------------
7523 procedure Expand_N_Op_Or (N : Node_Id) is
7524 Typ : constant Entity_Id := Etype (N);
7527 Binary_Op_Validity_Checks (N);
7529 if Is_Array_Type (Etype (N)) then
7530 Expand_Boolean_Operator (N);
7532 elsif Is_Boolean_Type (Etype (N)) then
7534 -- Replace OR by OR ELSE if Short_Circuit_And_Or active and the type
7535 -- is standard Boolean (do not mess with AND that uses a non-standard
7536 -- Boolean type, because something strange is going on).
7538 if Short_Circuit_And_Or and then Typ = Standard_Boolean then
7540 Make_Or_Else (Sloc (N),
7541 Left_Opnd => Relocate_Node (Left_Opnd (N)),
7542 Right_Opnd => Relocate_Node (Right_Opnd (N))));
7543 Analyze_And_Resolve (N, Typ);
7545 -- Otherwise, adjust conditions
7548 Adjust_Condition (Left_Opnd (N));
7549 Adjust_Condition (Right_Opnd (N));
7550 Set_Etype (N, Standard_Boolean);
7551 Adjust_Result_Type (N, Typ);
7554 elsif Is_Intrinsic_Subprogram (Entity (N)) then
7555 Expand_Intrinsic_Call (N, Entity (N));
7560 ----------------------
7561 -- Expand_N_Op_Plus --
7562 ----------------------
7564 procedure Expand_N_Op_Plus (N : Node_Id) is
7566 Unary_Op_Validity_Checks (N);
7567 end Expand_N_Op_Plus;
7569 ---------------------
7570 -- Expand_N_Op_Rem --
7571 ---------------------
7573 procedure Expand_N_Op_Rem (N : Node_Id) is
7574 Loc : constant Source_Ptr := Sloc (N);
7575 Typ : constant Entity_Id := Etype (N);
7577 Left : constant Node_Id := Left_Opnd (N);
7578 Right : constant Node_Id := Right_Opnd (N);
7586 -- Set if corresponding operand can be negative
7588 pragma Unreferenced (Hi);
7591 Binary_Op_Validity_Checks (N);
7593 if Is_Integer_Type (Etype (N)) then
7594 Apply_Divide_Check (N);
7597 -- Apply optimization x rem 1 = 0. We don't really need that with gcc,
7598 -- but it is useful with other back ends (e.g. AAMP), and is certainly
7601 if Is_Integer_Type (Etype (N))
7602 and then Compile_Time_Known_Value (Right)
7603 and then Expr_Value (Right) = Uint_1
7605 -- Call Remove_Side_Effects to ensure that any side effects in the
7606 -- ignored left operand (in particular function calls to user defined
7607 -- functions) are properly executed.
7609 Remove_Side_Effects (Left);
7611 Rewrite (N, Make_Integer_Literal (Loc, 0));
7612 Analyze_And_Resolve (N, Typ);
7616 -- Deal with annoying case of largest negative number remainder minus
7617 -- one. Gigi does not handle this case correctly, because it generates
7618 -- a divide instruction which may trap in this case.
7620 -- In fact the check is quite easy, if the right operand is -1, then
7621 -- the remainder is always 0, and we can just ignore the left operand
7622 -- completely in this case.
7624 Determine_Range (Right, OK, Lo, Hi, Assume_Valid => True);
7625 Lneg := (not OK) or else Lo < 0;
7627 Determine_Range (Left, OK, Lo, Hi, Assume_Valid => True);
7628 Rneg := (not OK) or else Lo < 0;
7630 -- We won't mess with trying to find out if the left operand can really
7631 -- be the largest negative number (that's a pain in the case of private
7632 -- types and this is really marginal). We will just assume that we need
7633 -- the test if the left operand can be negative at all.
7635 if Lneg and Rneg then
7637 Make_Conditional_Expression (Loc,
7638 Expressions => New_List (
7640 Left_Opnd => Duplicate_Subexpr (Right),
7642 Unchecked_Convert_To (Typ, Make_Integer_Literal (Loc, -1))),
7644 Unchecked_Convert_To (Typ,
7645 Make_Integer_Literal (Loc, Uint_0)),
7647 Relocate_Node (N))));
7649 Set_Analyzed (Next (Next (First (Expressions (N)))));
7650 Analyze_And_Resolve (N, Typ);
7652 end Expand_N_Op_Rem;
7654 -----------------------------
7655 -- Expand_N_Op_Rotate_Left --
7656 -----------------------------
7658 procedure Expand_N_Op_Rotate_Left (N : Node_Id) is
7660 Binary_Op_Validity_Checks (N);
7661 end Expand_N_Op_Rotate_Left;
7663 ------------------------------
7664 -- Expand_N_Op_Rotate_Right --
7665 ------------------------------
7667 procedure Expand_N_Op_Rotate_Right (N : Node_Id) is
7669 Binary_Op_Validity_Checks (N);
7670 end Expand_N_Op_Rotate_Right;
7672 ----------------------------
7673 -- Expand_N_Op_Shift_Left --
7674 ----------------------------
7676 procedure Expand_N_Op_Shift_Left (N : Node_Id) is
7678 Binary_Op_Validity_Checks (N);
7679 end Expand_N_Op_Shift_Left;
7681 -----------------------------
7682 -- Expand_N_Op_Shift_Right --
7683 -----------------------------
7685 procedure Expand_N_Op_Shift_Right (N : Node_Id) is
7687 Binary_Op_Validity_Checks (N);
7688 end Expand_N_Op_Shift_Right;
7690 ----------------------------------------
7691 -- Expand_N_Op_Shift_Right_Arithmetic --
7692 ----------------------------------------
7694 procedure Expand_N_Op_Shift_Right_Arithmetic (N : Node_Id) is
7696 Binary_Op_Validity_Checks (N);
7697 end Expand_N_Op_Shift_Right_Arithmetic;
7699 --------------------------
7700 -- Expand_N_Op_Subtract --
7701 --------------------------
7703 procedure Expand_N_Op_Subtract (N : Node_Id) is
7704 Typ : constant Entity_Id := Etype (N);
7707 Binary_Op_Validity_Checks (N);
7709 -- N - 0 = N for integer types
7711 if Is_Integer_Type (Typ)
7712 and then Compile_Time_Known_Value (Right_Opnd (N))
7713 and then Expr_Value (Right_Opnd (N)) = 0
7715 Rewrite (N, Left_Opnd (N));
7719 -- Arithmetic overflow checks for signed integer/fixed point types
7721 if Is_Signed_Integer_Type (Typ)
7723 Is_Fixed_Point_Type (Typ)
7725 Apply_Arithmetic_Overflow_Check (N);
7727 -- VAX floating-point types case
7729 elsif Vax_Float (Typ) then
7730 Expand_Vax_Arith (N);
7732 end Expand_N_Op_Subtract;
7734 ---------------------
7735 -- Expand_N_Op_Xor --
7736 ---------------------
7738 procedure Expand_N_Op_Xor (N : Node_Id) is
7739 Typ : constant Entity_Id := Etype (N);
7742 Binary_Op_Validity_Checks (N);
7744 if Is_Array_Type (Etype (N)) then
7745 Expand_Boolean_Operator (N);
7747 elsif Is_Boolean_Type (Etype (N)) then
7748 Adjust_Condition (Left_Opnd (N));
7749 Adjust_Condition (Right_Opnd (N));
7750 Set_Etype (N, Standard_Boolean);
7751 Adjust_Result_Type (N, Typ);
7753 elsif Is_Intrinsic_Subprogram (Entity (N)) then
7754 Expand_Intrinsic_Call (N, Entity (N));
7757 end Expand_N_Op_Xor;
7759 ----------------------
7760 -- Expand_N_Or_Else --
7761 ----------------------
7763 procedure Expand_N_Or_Else (N : Node_Id)
7764 renames Expand_Short_Circuit_Operator;
7766 -----------------------------------
7767 -- Expand_N_Qualified_Expression --
7768 -----------------------------------
7770 procedure Expand_N_Qualified_Expression (N : Node_Id) is
7771 Operand : constant Node_Id := Expression (N);
7772 Target_Type : constant Entity_Id := Entity (Subtype_Mark (N));
7775 -- Do validity check if validity checking operands
7777 if Validity_Checks_On
7778 and then Validity_Check_Operands
7780 Ensure_Valid (Operand);
7783 -- Apply possible constraint check
7785 Apply_Constraint_Check (Operand, Target_Type, No_Sliding => True);
7787 if Do_Range_Check (Operand) then
7788 Set_Do_Range_Check (Operand, False);
7789 Generate_Range_Check (Operand, Target_Type, CE_Range_Check_Failed);
7791 end Expand_N_Qualified_Expression;
7793 ------------------------------------
7794 -- Expand_N_Quantified_Expression --
7795 ------------------------------------
7799 -- for all X in range => Cond
7804 -- for X in range loop
7811 -- Conversely, an existentially quantified expression:
7813 -- for some X in range => Cond
7818 -- for X in range loop
7825 -- In both cases, the iteration may be over a container in which case it is
7826 -- given by an iterator specification, not a loop parameter specification.
7828 procedure Expand_N_Quantified_Expression (N : Node_Id) is
7829 Loc : constant Source_Ptr := Sloc (N);
7830 Is_Universal : constant Boolean := All_Present (N);
7831 Actions : constant List_Id := New_List;
7832 Tnn : constant Entity_Id := Make_Temporary (Loc, 'T', N);
7840 Make_Object_Declaration (Loc,
7841 Defining_Identifier => Tnn,
7842 Object_Definition => New_Occurrence_Of (Standard_Boolean, Loc),
7844 New_Occurrence_Of (Boolean_Literals (Is_Universal), Loc));
7845 Append_To (Actions, Decl);
7847 Cond := Relocate_Node (Condition (N));
7849 -- Reset flag analyzed in the condition to force its analysis. Required
7850 -- since the previous analysis was done with expansion disabled (see
7851 -- Resolve_Quantified_Expression) and hence checks were not inserted
7852 -- and record comparisons have not been expanded.
7854 Reset_Analyzed_Flags (Cond);
7856 if Is_Universal then
7857 Cond := Make_Op_Not (Loc, Cond);
7861 Make_Implicit_If_Statement (N,
7863 Then_Statements => New_List (
7864 Make_Assignment_Statement (Loc,
7865 Name => New_Occurrence_Of (Tnn, Loc),
7867 New_Occurrence_Of (Boolean_Literals (not Is_Universal), Loc)),
7868 Make_Exit_Statement (Loc)));
7870 if Present (Loop_Parameter_Specification (N)) then
7872 Make_Iteration_Scheme (Loc,
7873 Loop_Parameter_Specification =>
7874 Loop_Parameter_Specification (N));
7877 Make_Iteration_Scheme (Loc,
7878 Iterator_Specification => Iterator_Specification (N));
7882 Make_Loop_Statement (Loc,
7883 Iteration_Scheme => I_Scheme,
7884 Statements => New_List (Test),
7885 End_Label => Empty));
7888 Make_Expression_With_Actions (Loc,
7889 Expression => New_Occurrence_Of (Tnn, Loc),
7890 Actions => Actions));
7892 Analyze_And_Resolve (N, Standard_Boolean);
7893 end Expand_N_Quantified_Expression;
7895 ---------------------------------
7896 -- Expand_N_Selected_Component --
7897 ---------------------------------
7899 -- If the selector is a discriminant of a concurrent object, rewrite the
7900 -- prefix to denote the corresponding record type.
7902 procedure Expand_N_Selected_Component (N : Node_Id) is
7903 Loc : constant Source_Ptr := Sloc (N);
7904 Par : constant Node_Id := Parent (N);
7905 P : constant Node_Id := Prefix (N);
7906 Ptyp : Entity_Id := Underlying_Type (Etype (P));
7912 function In_Left_Hand_Side (Comp : Node_Id) return Boolean;
7913 -- Gigi needs a temporary for prefixes that depend on a discriminant,
7914 -- unless the context of an assignment can provide size information.
7915 -- Don't we have a general routine that does this???
7917 function Is_Subtype_Declaration return Boolean;
7918 -- The replacement of a discriminant reference by its value is required
7919 -- if this is part of the initialization of an temporary generated by a
7920 -- change of representation. This shows up as the construction of a
7921 -- discriminant constraint for a subtype declared at the same point as
7922 -- the entity in the prefix of the selected component. We recognize this
7923 -- case when the context of the reference is:
7924 -- subtype ST is T(Obj.D);
7925 -- where the entity for Obj comes from source, and ST has the same sloc.
7927 -----------------------
7928 -- In_Left_Hand_Side --
7929 -----------------------
7931 function In_Left_Hand_Side (Comp : Node_Id) return Boolean is
7933 return (Nkind (Parent (Comp)) = N_Assignment_Statement
7934 and then Comp = Name (Parent (Comp)))
7935 or else (Present (Parent (Comp))
7936 and then Nkind (Parent (Comp)) in N_Subexpr
7937 and then In_Left_Hand_Side (Parent (Comp)));
7938 end In_Left_Hand_Side;
7940 -----------------------------
7941 -- Is_Subtype_Declaration --
7942 -----------------------------
7944 function Is_Subtype_Declaration return Boolean is
7945 Par : constant Node_Id := Parent (N);
7948 Nkind (Par) = N_Index_Or_Discriminant_Constraint
7949 and then Nkind (Parent (Parent (Par))) = N_Subtype_Declaration
7950 and then Comes_From_Source (Entity (Prefix (N)))
7951 and then Sloc (Par) = Sloc (Entity (Prefix (N)));
7952 end Is_Subtype_Declaration;
7954 -- Start of processing for Expand_N_Selected_Component
7957 -- Insert explicit dereference if required
7959 if Is_Access_Type (Ptyp) then
7961 -- First set prefix type to proper access type, in case it currently
7962 -- has a private (non-access) view of this type.
7964 Set_Etype (P, Ptyp);
7966 Insert_Explicit_Dereference (P);
7967 Analyze_And_Resolve (P, Designated_Type (Ptyp));
7969 if Ekind (Etype (P)) = E_Private_Subtype
7970 and then Is_For_Access_Subtype (Etype (P))
7972 Set_Etype (P, Base_Type (Etype (P)));
7978 -- Deal with discriminant check required
7980 if Do_Discriminant_Check (N) then
7982 -- Present the discriminant checking function to the backend, so that
7983 -- it can inline the call to the function.
7986 (Discriminant_Checking_Func
7987 (Original_Record_Component (Entity (Selector_Name (N)))));
7989 -- Now reset the flag and generate the call
7991 Set_Do_Discriminant_Check (N, False);
7992 Generate_Discriminant_Check (N);
7995 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
7996 -- function, then additional actuals must be passed.
7998 if Ada_Version >= Ada_2005
7999 and then Is_Build_In_Place_Function_Call (P)
8001 Make_Build_In_Place_Call_In_Anonymous_Context (P);
8004 -- Gigi cannot handle unchecked conversions that are the prefix of a
8005 -- selected component with discriminants. This must be checked during
8006 -- expansion, because during analysis the type of the selector is not
8007 -- known at the point the prefix is analyzed. If the conversion is the
8008 -- target of an assignment, then we cannot force the evaluation.
8010 if Nkind (Prefix (N)) = N_Unchecked_Type_Conversion
8011 and then Has_Discriminants (Etype (N))
8012 and then not In_Left_Hand_Side (N)
8014 Force_Evaluation (Prefix (N));
8017 -- Remaining processing applies only if selector is a discriminant
8019 if Ekind (Entity (Selector_Name (N))) = E_Discriminant then
8021 -- If the selector is a discriminant of a constrained record type,
8022 -- we may be able to rewrite the expression with the actual value
8023 -- of the discriminant, a useful optimization in some cases.
8025 if Is_Record_Type (Ptyp)
8026 and then Has_Discriminants (Ptyp)
8027 and then Is_Constrained (Ptyp)
8029 -- Do this optimization for discrete types only, and not for
8030 -- access types (access discriminants get us into trouble!)
8032 if not Is_Discrete_Type (Etype (N)) then
8035 -- Don't do this on the left hand of an assignment statement.
8036 -- Normally one would think that references like this would not
8037 -- occur, but they do in generated code, and mean that we really
8038 -- do want to assign the discriminant!
8040 elsif Nkind (Par) = N_Assignment_Statement
8041 and then Name (Par) = N
8045 -- Don't do this optimization for the prefix of an attribute or
8046 -- the name of an object renaming declaration since these are
8047 -- contexts where we do not want the value anyway.
8049 elsif (Nkind (Par) = N_Attribute_Reference
8050 and then Prefix (Par) = N)
8051 or else Is_Renamed_Object (N)
8055 -- Don't do this optimization if we are within the code for a
8056 -- discriminant check, since the whole point of such a check may
8057 -- be to verify the condition on which the code below depends!
8059 elsif Is_In_Discriminant_Check (N) then
8062 -- Green light to see if we can do the optimization. There is
8063 -- still one condition that inhibits the optimization below but
8064 -- now is the time to check the particular discriminant.
8067 -- Loop through discriminants to find the matching discriminant
8068 -- constraint to see if we can copy it.
8070 Disc := First_Discriminant (Ptyp);
8071 Dcon := First_Elmt (Discriminant_Constraint (Ptyp));
8072 Discr_Loop : while Present (Dcon) loop
8073 Dval := Node (Dcon);
8075 -- Check if this is the matching discriminant and if the
8076 -- discriminant value is simple enough to make sense to
8077 -- copy. We don't want to copy complex expressions, and
8078 -- indeed to do so can cause trouble (before we put in
8079 -- this guard, a discriminant expression containing an
8080 -- AND THEN was copied, causing problems for coverage
8083 -- However, if the reference is part of the initialization
8084 -- code generated for an object declaration, we must use
8085 -- the discriminant value from the subtype constraint,
8086 -- because the selected component may be a reference to the
8087 -- object being initialized, whose discriminant is not yet
8088 -- set. This only happens in complex cases involving changes
8089 -- or representation.
8091 if Disc = Entity (Selector_Name (N))
8092 and then (Is_Entity_Name (Dval)
8093 or else Compile_Time_Known_Value (Dval)
8094 or else Is_Subtype_Declaration)
8096 -- Here we have the matching discriminant. Check for
8097 -- the case of a discriminant of a component that is
8098 -- constrained by an outer discriminant, which cannot
8099 -- be optimized away.
8101 if Denotes_Discriminant
8102 (Dval, Check_Concurrent => True)
8106 elsif Nkind (Original_Node (Dval)) = N_Selected_Component
8108 Denotes_Discriminant
8109 (Selector_Name (Original_Node (Dval)), True)
8113 -- Do not retrieve value if constraint is not static. It
8114 -- is generally not useful, and the constraint may be a
8115 -- rewritten outer discriminant in which case it is in
8118 elsif Is_Entity_Name (Dval)
8119 and then Nkind (Parent (Entity (Dval))) =
8120 N_Object_Declaration
8121 and then Present (Expression (Parent (Entity (Dval))))
8123 not Is_Static_Expression
8124 (Expression (Parent (Entity (Dval))))
8128 -- In the context of a case statement, the expression may
8129 -- have the base type of the discriminant, and we need to
8130 -- preserve the constraint to avoid spurious errors on
8133 elsif Nkind (Parent (N)) = N_Case_Statement
8134 and then Etype (Dval) /= Etype (Disc)
8137 Make_Qualified_Expression (Loc,
8139 New_Occurrence_Of (Etype (Disc), Loc),
8141 New_Copy_Tree (Dval)));
8142 Analyze_And_Resolve (N, Etype (Disc));
8144 -- In case that comes out as a static expression,
8145 -- reset it (a selected component is never static).
8147 Set_Is_Static_Expression (N, False);
8150 -- Otherwise we can just copy the constraint, but the
8151 -- result is certainly not static! In some cases the
8152 -- discriminant constraint has been analyzed in the
8153 -- context of the original subtype indication, but for
8154 -- itypes the constraint might not have been analyzed
8155 -- yet, and this must be done now.
8158 Rewrite (N, New_Copy_Tree (Dval));
8159 Analyze_And_Resolve (N);
8160 Set_Is_Static_Expression (N, False);
8166 Next_Discriminant (Disc);
8167 end loop Discr_Loop;
8169 -- Note: the above loop should always find a matching
8170 -- discriminant, but if it does not, we just missed an
8171 -- optimization due to some glitch (perhaps a previous
8172 -- error), so ignore.
8177 -- The only remaining processing is in the case of a discriminant of
8178 -- a concurrent object, where we rewrite the prefix to denote the
8179 -- corresponding record type. If the type is derived and has renamed
8180 -- discriminants, use corresponding discriminant, which is the one
8181 -- that appears in the corresponding record.
8183 if not Is_Concurrent_Type (Ptyp) then
8187 Disc := Entity (Selector_Name (N));
8189 if Is_Derived_Type (Ptyp)
8190 and then Present (Corresponding_Discriminant (Disc))
8192 Disc := Corresponding_Discriminant (Disc);
8196 Make_Selected_Component (Loc,
8198 Unchecked_Convert_To (Corresponding_Record_Type (Ptyp),
8200 Selector_Name => Make_Identifier (Loc, Chars (Disc)));
8205 end Expand_N_Selected_Component;
8207 --------------------
8208 -- Expand_N_Slice --
8209 --------------------
8211 procedure Expand_N_Slice (N : Node_Id) is
8212 Loc : constant Source_Ptr := Sloc (N);
8213 Typ : constant Entity_Id := Etype (N);
8214 Pfx : constant Node_Id := Prefix (N);
8215 Ptp : Entity_Id := Etype (Pfx);
8217 function Is_Procedure_Actual (N : Node_Id) return Boolean;
8218 -- Check whether the argument is an actual for a procedure call, in
8219 -- which case the expansion of a bit-packed slice is deferred until the
8220 -- call itself is expanded. The reason this is required is that we might
8221 -- have an IN OUT or OUT parameter, and the copy out is essential, and
8222 -- that copy out would be missed if we created a temporary here in
8223 -- Expand_N_Slice. Note that we don't bother to test specifically for an
8224 -- IN OUT or OUT mode parameter, since it is a bit tricky to do, and it
8225 -- is harmless to defer expansion in the IN case, since the call
8226 -- processing will still generate the appropriate copy in operation,
8227 -- which will take care of the slice.
8229 procedure Make_Temporary_For_Slice;
8230 -- Create a named variable for the value of the slice, in cases where
8231 -- the back-end cannot handle it properly, e.g. when packed types or
8232 -- unaligned slices are involved.
8234 -------------------------
8235 -- Is_Procedure_Actual --
8236 -------------------------
8238 function Is_Procedure_Actual (N : Node_Id) return Boolean is
8239 Par : Node_Id := Parent (N);
8243 -- If our parent is a procedure call we can return
8245 if Nkind (Par) = N_Procedure_Call_Statement then
8248 -- If our parent is a type conversion, keep climbing the tree,
8249 -- since a type conversion can be a procedure actual. Also keep
8250 -- climbing if parameter association or a qualified expression,
8251 -- since these are additional cases that do can appear on
8252 -- procedure actuals.
8254 elsif Nkind_In (Par, N_Type_Conversion,
8255 N_Parameter_Association,
8256 N_Qualified_Expression)
8258 Par := Parent (Par);
8260 -- Any other case is not what we are looking for
8266 end Is_Procedure_Actual;
8268 ------------------------------
8269 -- Make_Temporary_For_Slice --
8270 ------------------------------
8272 procedure Make_Temporary_For_Slice is
8274 Ent : constant Entity_Id := Make_Temporary (Loc, 'T', N);
8278 Make_Object_Declaration (Loc,
8279 Defining_Identifier => Ent,
8280 Object_Definition => New_Occurrence_Of (Typ, Loc));
8282 Set_No_Initialization (Decl);
8284 Insert_Actions (N, New_List (
8286 Make_Assignment_Statement (Loc,
8287 Name => New_Occurrence_Of (Ent, Loc),
8288 Expression => Relocate_Node (N))));
8290 Rewrite (N, New_Occurrence_Of (Ent, Loc));
8291 Analyze_And_Resolve (N, Typ);
8292 end Make_Temporary_For_Slice;
8294 -- Start of processing for Expand_N_Slice
8297 -- Special handling for access types
8299 if Is_Access_Type (Ptp) then
8301 Ptp := Designated_Type (Ptp);
8304 Make_Explicit_Dereference (Sloc (N),
8305 Prefix => Relocate_Node (Pfx)));
8307 Analyze_And_Resolve (Pfx, Ptp);
8310 -- Ada 2005 (AI-318-02): If the prefix is a call to a build-in-place
8311 -- function, then additional actuals must be passed.
8313 if Ada_Version >= Ada_2005
8314 and then Is_Build_In_Place_Function_Call (Pfx)
8316 Make_Build_In_Place_Call_In_Anonymous_Context (Pfx);
8319 -- The remaining case to be handled is packed slices. We can leave
8320 -- packed slices as they are in the following situations:
8322 -- 1. Right or left side of an assignment (we can handle this
8323 -- situation correctly in the assignment statement expansion).
8325 -- 2. Prefix of indexed component (the slide is optimized away in this
8326 -- case, see the start of Expand_N_Slice.)
8328 -- 3. Object renaming declaration, since we want the name of the
8329 -- slice, not the value.
8331 -- 4. Argument to procedure call, since copy-in/copy-out handling may
8332 -- be required, and this is handled in the expansion of call
8335 -- 5. Prefix of an address attribute (this is an error which is caught
8336 -- elsewhere, and the expansion would interfere with generating the
8339 if not Is_Packed (Typ) then
8341 -- Apply transformation for actuals of a function call, where
8342 -- Expand_Actuals is not used.
8344 if Nkind (Parent (N)) = N_Function_Call
8345 and then Is_Possibly_Unaligned_Slice (N)
8347 Make_Temporary_For_Slice;
8350 elsif Nkind (Parent (N)) = N_Assignment_Statement
8351 or else (Nkind (Parent (Parent (N))) = N_Assignment_Statement
8352 and then Parent (N) = Name (Parent (Parent (N))))
8356 elsif Nkind (Parent (N)) = N_Indexed_Component
8357 or else Is_Renamed_Object (N)
8358 or else Is_Procedure_Actual (N)
8362 elsif Nkind (Parent (N)) = N_Attribute_Reference
8363 and then Attribute_Name (Parent (N)) = Name_Address
8368 Make_Temporary_For_Slice;
8372 ------------------------------
8373 -- Expand_N_Type_Conversion --
8374 ------------------------------
8376 procedure Expand_N_Type_Conversion (N : Node_Id) is
8377 Loc : constant Source_Ptr := Sloc (N);
8378 Operand : constant Node_Id := Expression (N);
8379 Target_Type : constant Entity_Id := Etype (N);
8380 Operand_Type : Entity_Id := Etype (Operand);
8382 procedure Handle_Changed_Representation;
8383 -- This is called in the case of record and array type conversions to
8384 -- see if there is a change of representation to be handled. Change of
8385 -- representation is actually handled at the assignment statement level,
8386 -- and what this procedure does is rewrite node N conversion as an
8387 -- assignment to temporary. If there is no change of representation,
8388 -- then the conversion node is unchanged.
8390 procedure Raise_Accessibility_Error;
8391 -- Called when we know that an accessibility check will fail. Rewrites
8392 -- node N to an appropriate raise statement and outputs warning msgs.
8393 -- The Etype of the raise node is set to Target_Type.
8395 procedure Real_Range_Check;
8396 -- Handles generation of range check for real target value
8398 function Has_Extra_Accessibility (Id : Entity_Id) return Boolean;
8399 -- True iff Present (Effective_Extra_Accessibility (Id)) successfully
8400 -- evaluates to True.
8402 -----------------------------------
8403 -- Handle_Changed_Representation --
8404 -----------------------------------
8406 procedure Handle_Changed_Representation is
8415 -- Nothing else to do if no change of representation
8417 if Same_Representation (Operand_Type, Target_Type) then
8420 -- The real change of representation work is done by the assignment
8421 -- statement processing. So if this type conversion is appearing as
8422 -- the expression of an assignment statement, nothing needs to be
8423 -- done to the conversion.
8425 elsif Nkind (Parent (N)) = N_Assignment_Statement then
8428 -- Otherwise we need to generate a temporary variable, and do the
8429 -- change of representation assignment into that temporary variable.
8430 -- The conversion is then replaced by a reference to this variable.
8435 -- If type is unconstrained we have to add a constraint, copied
8436 -- from the actual value of the left hand side.
8438 if not Is_Constrained (Target_Type) then
8439 if Has_Discriminants (Operand_Type) then
8440 Disc := First_Discriminant (Operand_Type);
8442 if Disc /= First_Stored_Discriminant (Operand_Type) then
8443 Disc := First_Stored_Discriminant (Operand_Type);
8447 while Present (Disc) loop
8449 Make_Selected_Component (Loc,
8451 Duplicate_Subexpr_Move_Checks (Operand),
8453 Make_Identifier (Loc, Chars (Disc))));
8454 Next_Discriminant (Disc);
8457 elsif Is_Array_Type (Operand_Type) then
8458 N_Ix := First_Index (Target_Type);
8461 for J in 1 .. Number_Dimensions (Operand_Type) loop
8463 -- We convert the bounds explicitly. We use an unchecked
8464 -- conversion because bounds checks are done elsewhere.
8469 Unchecked_Convert_To (Etype (N_Ix),
8470 Make_Attribute_Reference (Loc,
8472 Duplicate_Subexpr_No_Checks
8473 (Operand, Name_Req => True),
8474 Attribute_Name => Name_First,
8475 Expressions => New_List (
8476 Make_Integer_Literal (Loc, J)))),
8479 Unchecked_Convert_To (Etype (N_Ix),
8480 Make_Attribute_Reference (Loc,
8482 Duplicate_Subexpr_No_Checks
8483 (Operand, Name_Req => True),
8484 Attribute_Name => Name_Last,
8485 Expressions => New_List (
8486 Make_Integer_Literal (Loc, J))))));
8493 Odef := New_Occurrence_Of (Target_Type, Loc);
8495 if Present (Cons) then
8497 Make_Subtype_Indication (Loc,
8498 Subtype_Mark => Odef,
8500 Make_Index_Or_Discriminant_Constraint (Loc,
8501 Constraints => Cons));
8504 Temp := Make_Temporary (Loc, 'C');
8506 Make_Object_Declaration (Loc,
8507 Defining_Identifier => Temp,
8508 Object_Definition => Odef);
8510 Set_No_Initialization (Decl, True);
8512 -- Insert required actions. It is essential to suppress checks
8513 -- since we have suppressed default initialization, which means
8514 -- that the variable we create may have no discriminants.
8519 Make_Assignment_Statement (Loc,
8520 Name => New_Occurrence_Of (Temp, Loc),
8521 Expression => Relocate_Node (N))),
8522 Suppress => All_Checks);
8524 Rewrite (N, New_Occurrence_Of (Temp, Loc));
8527 end Handle_Changed_Representation;
8529 -------------------------------
8530 -- Raise_Accessibility_Error --
8531 -------------------------------
8533 procedure Raise_Accessibility_Error is
8536 Make_Raise_Program_Error (Sloc (N),
8537 Reason => PE_Accessibility_Check_Failed));
8538 Set_Etype (N, Target_Type);
8540 Error_Msg_N ("?accessibility check failure", N);
8542 ("\?& will be raised at run time", N, Standard_Program_Error);
8543 end Raise_Accessibility_Error;
8545 ----------------------
8546 -- Real_Range_Check --
8547 ----------------------
8549 -- Case of conversions to floating-point or fixed-point. If range checks
8550 -- are enabled and the target type has a range constraint, we convert:
8556 -- Tnn : typ'Base := typ'Base (x);
8557 -- [constraint_error when Tnn < typ'First or else Tnn > typ'Last]
8560 -- This is necessary when there is a conversion of integer to float or
8561 -- to fixed-point to ensure that the correct checks are made. It is not
8562 -- necessary for float to float where it is enough to simply set the
8563 -- Do_Range_Check flag.
8565 procedure Real_Range_Check is
8566 Btyp : constant Entity_Id := Base_Type (Target_Type);
8567 Lo : constant Node_Id := Type_Low_Bound (Target_Type);
8568 Hi : constant Node_Id := Type_High_Bound (Target_Type);
8569 Xtyp : constant Entity_Id := Etype (Operand);
8574 -- Nothing to do if conversion was rewritten
8576 if Nkind (N) /= N_Type_Conversion then
8580 -- Nothing to do if range checks suppressed, or target has the same
8581 -- range as the base type (or is the base type).
8583 if Range_Checks_Suppressed (Target_Type)
8584 or else (Lo = Type_Low_Bound (Btyp)
8586 Hi = Type_High_Bound (Btyp))
8591 -- Nothing to do if expression is an entity on which checks have been
8594 if Is_Entity_Name (Operand)
8595 and then Range_Checks_Suppressed (Entity (Operand))
8600 -- Nothing to do if bounds are all static and we can tell that the
8601 -- expression is within the bounds of the target. Note that if the
8602 -- operand is of an unconstrained floating-point type, then we do
8603 -- not trust it to be in range (might be infinite)
8606 S_Lo : constant Node_Id := Type_Low_Bound (Xtyp);
8607 S_Hi : constant Node_Id := Type_High_Bound (Xtyp);
8610 if (not Is_Floating_Point_Type (Xtyp)
8611 or else Is_Constrained (Xtyp))
8612 and then Compile_Time_Known_Value (S_Lo)
8613 and then Compile_Time_Known_Value (S_Hi)
8614 and then Compile_Time_Known_Value (Hi)
8615 and then Compile_Time_Known_Value (Lo)
8618 D_Lov : constant Ureal := Expr_Value_R (Lo);
8619 D_Hiv : constant Ureal := Expr_Value_R (Hi);
8624 if Is_Real_Type (Xtyp) then
8625 S_Lov := Expr_Value_R (S_Lo);
8626 S_Hiv := Expr_Value_R (S_Hi);
8628 S_Lov := UR_From_Uint (Expr_Value (S_Lo));
8629 S_Hiv := UR_From_Uint (Expr_Value (S_Hi));
8633 and then S_Lov >= D_Lov
8634 and then S_Hiv <= D_Hiv
8636 Set_Do_Range_Check (Operand, False);
8643 -- For float to float conversions, we are done
8645 if Is_Floating_Point_Type (Xtyp)
8647 Is_Floating_Point_Type (Btyp)
8652 -- Otherwise rewrite the conversion as described above
8654 Conv := Relocate_Node (N);
8655 Rewrite (Subtype_Mark (Conv), New_Occurrence_Of (Btyp, Loc));
8656 Set_Etype (Conv, Btyp);
8658 -- Enable overflow except for case of integer to float conversions,
8659 -- where it is never required, since we can never have overflow in
8662 if not Is_Integer_Type (Etype (Operand)) then
8663 Enable_Overflow_Check (Conv);
8666 Tnn := Make_Temporary (Loc, 'T', Conv);
8668 Insert_Actions (N, New_List (
8669 Make_Object_Declaration (Loc,
8670 Defining_Identifier => Tnn,
8671 Object_Definition => New_Occurrence_Of (Btyp, Loc),
8672 Constant_Present => True,
8673 Expression => Conv),
8675 Make_Raise_Constraint_Error (Loc,
8680 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
8682 Make_Attribute_Reference (Loc,
8683 Attribute_Name => Name_First,
8685 New_Occurrence_Of (Target_Type, Loc))),
8689 Left_Opnd => New_Occurrence_Of (Tnn, Loc),
8691 Make_Attribute_Reference (Loc,
8692 Attribute_Name => Name_Last,
8694 New_Occurrence_Of (Target_Type, Loc)))),
8695 Reason => CE_Range_Check_Failed)));
8697 Rewrite (N, New_Occurrence_Of (Tnn, Loc));
8698 Analyze_And_Resolve (N, Btyp);
8699 end Real_Range_Check;
8701 -----------------------------
8702 -- Has_Extra_Accessibility --
8703 -----------------------------
8705 -- Returns true for a formal of an anonymous access type or for
8706 -- an Ada 2012-style stand-alone object of an anonymous access type.
8708 function Has_Extra_Accessibility (Id : Entity_Id) return Boolean is
8710 if Is_Formal (Id) or else Ekind_In (Id, E_Constant, E_Variable) then
8711 return Present (Effective_Extra_Accessibility (Id));
8715 end Has_Extra_Accessibility;
8717 -- Start of processing for Expand_N_Type_Conversion
8720 -- Nothing at all to do if conversion is to the identical type so remove
8721 -- the conversion completely, it is useless, except that it may carry
8722 -- an Assignment_OK attribute, which must be propagated to the operand.
8724 if Operand_Type = Target_Type then
8725 if Assignment_OK (N) then
8726 Set_Assignment_OK (Operand);
8729 Rewrite (N, Relocate_Node (Operand));
8733 -- Nothing to do if this is the second argument of read. This is a
8734 -- "backwards" conversion that will be handled by the specialized code
8735 -- in attribute processing.
8737 if Nkind (Parent (N)) = N_Attribute_Reference
8738 and then Attribute_Name (Parent (N)) = Name_Read
8739 and then Next (First (Expressions (Parent (N)))) = N
8744 -- Check for case of converting to a type that has an invariant
8745 -- associated with it. This required an invariant check. We convert
8751 -- do invariant_check (typ (expr)) in typ (expr);
8753 -- using Duplicate_Subexpr to avoid multiple side effects
8755 -- Note: the Comes_From_Source check, and then the resetting of this
8756 -- flag prevents what would otherwise be an infinite recursion.
8758 if Has_Invariants (Target_Type)
8759 and then Present (Invariant_Procedure (Target_Type))
8760 and then Comes_From_Source (N)
8762 Set_Comes_From_Source (N, False);
8764 Make_Expression_With_Actions (Loc,
8765 Actions => New_List (
8766 Make_Invariant_Call (Duplicate_Subexpr (N))),
8767 Expression => Duplicate_Subexpr_No_Checks (N)));
8768 Analyze_And_Resolve (N, Target_Type);
8772 -- Here if we may need to expand conversion
8774 -- If the operand of the type conversion is an arithmetic operation on
8775 -- signed integers, and the based type of the signed integer type in
8776 -- question is smaller than Standard.Integer, we promote both of the
8777 -- operands to type Integer.
8779 -- For example, if we have
8781 -- target-type (opnd1 + opnd2)
8783 -- and opnd1 and opnd2 are of type short integer, then we rewrite
8786 -- target-type (integer(opnd1) + integer(opnd2))
8788 -- We do this because we are always allowed to compute in a larger type
8789 -- if we do the right thing with the result, and in this case we are
8790 -- going to do a conversion which will do an appropriate check to make
8791 -- sure that things are in range of the target type in any case. This
8792 -- avoids some unnecessary intermediate overflows.
8794 -- We might consider a similar transformation in the case where the
8795 -- target is a real type or a 64-bit integer type, and the operand
8796 -- is an arithmetic operation using a 32-bit integer type. However,
8797 -- we do not bother with this case, because it could cause significant
8798 -- inefficiencies on 32-bit machines. On a 64-bit machine it would be
8799 -- much cheaper, but we don't want different behavior on 32-bit and
8800 -- 64-bit machines. Note that the exclusion of the 64-bit case also
8801 -- handles the configurable run-time cases where 64-bit arithmetic
8802 -- may simply be unavailable.
8804 -- Note: this circuit is partially redundant with respect to the circuit
8805 -- in Checks.Apply_Arithmetic_Overflow_Check, but we catch more cases in
8806 -- the processing here. Also we still need the Checks circuit, since we
8807 -- have to be sure not to generate junk overflow checks in the first
8808 -- place, since it would be trick to remove them here!
8810 if Integer_Promotion_Possible (N) then
8812 -- All conditions met, go ahead with transformation
8820 Make_Type_Conversion (Loc,
8821 Subtype_Mark => New_Reference_To (Standard_Integer, Loc),
8822 Expression => Relocate_Node (Right_Opnd (Operand)));
8824 Opnd := New_Op_Node (Nkind (Operand), Loc);
8825 Set_Right_Opnd (Opnd, R);
8827 if Nkind (Operand) in N_Binary_Op then
8829 Make_Type_Conversion (Loc,
8830 Subtype_Mark => New_Reference_To (Standard_Integer, Loc),
8831 Expression => Relocate_Node (Left_Opnd (Operand)));
8833 Set_Left_Opnd (Opnd, L);
8837 Make_Type_Conversion (Loc,
8838 Subtype_Mark => Relocate_Node (Subtype_Mark (N)),
8839 Expression => Opnd));
8841 Analyze_And_Resolve (N, Target_Type);
8846 -- Do validity check if validity checking operands
8848 if Validity_Checks_On
8849 and then Validity_Check_Operands
8851 Ensure_Valid (Operand);
8854 -- Special case of converting from non-standard boolean type
8856 if Is_Boolean_Type (Operand_Type)
8857 and then (Nonzero_Is_True (Operand_Type))
8859 Adjust_Condition (Operand);
8860 Set_Etype (Operand, Standard_Boolean);
8861 Operand_Type := Standard_Boolean;
8864 -- Case of converting to an access type
8866 if Is_Access_Type (Target_Type) then
8868 -- Apply an accessibility check when the conversion operand is an
8869 -- access parameter (or a renaming thereof), unless conversion was
8870 -- expanded from an Unchecked_ or Unrestricted_Access attribute.
8871 -- Note that other checks may still need to be applied below (such
8872 -- as tagged type checks).
8874 if Is_Entity_Name (Operand)
8875 and then Has_Extra_Accessibility (Entity (Operand))
8876 and then Ekind (Etype (Operand)) = E_Anonymous_Access_Type
8877 and then (Nkind (Original_Node (N)) /= N_Attribute_Reference
8878 or else Attribute_Name (Original_Node (N)) = Name_Access)
8880 Apply_Accessibility_Check
8881 (Operand, Target_Type, Insert_Node => Operand);
8883 -- If the level of the operand type is statically deeper than the
8884 -- level of the target type, then force Program_Error. Note that this
8885 -- can only occur for cases where the attribute is within the body of
8886 -- an instantiation (otherwise the conversion will already have been
8887 -- rejected as illegal). Note: warnings are issued by the analyzer
8888 -- for the instance cases.
8890 elsif In_Instance_Body
8891 and then Type_Access_Level (Operand_Type) >
8892 Type_Access_Level (Target_Type)
8894 Raise_Accessibility_Error;
8896 -- When the operand is a selected access discriminant the check needs
8897 -- to be made against the level of the object denoted by the prefix
8898 -- of the selected name. Force Program_Error for this case as well
8899 -- (this accessibility violation can only happen if within the body
8900 -- of an instantiation).
8902 elsif In_Instance_Body
8903 and then Ekind (Operand_Type) = E_Anonymous_Access_Type
8904 and then Nkind (Operand) = N_Selected_Component
8905 and then Object_Access_Level (Operand) >
8906 Type_Access_Level (Target_Type)
8908 Raise_Accessibility_Error;
8913 -- Case of conversions of tagged types and access to tagged types
8915 -- When needed, that is to say when the expression is class-wide, Add
8916 -- runtime a tag check for (strict) downward conversion by using the
8917 -- membership test, generating:
8919 -- [constraint_error when Operand not in Target_Type'Class]
8921 -- or in the access type case
8923 -- [constraint_error
8924 -- when Operand /= null
8925 -- and then Operand.all not in
8926 -- Designated_Type (Target_Type)'Class]
8928 if (Is_Access_Type (Target_Type)
8929 and then Is_Tagged_Type (Designated_Type (Target_Type)))
8930 or else Is_Tagged_Type (Target_Type)
8932 -- Do not do any expansion in the access type case if the parent is a
8933 -- renaming, since this is an error situation which will be caught by
8934 -- Sem_Ch8, and the expansion can interfere with this error check.
8936 if Is_Access_Type (Target_Type) and then Is_Renamed_Object (N) then
8940 -- Otherwise, proceed with processing tagged conversion
8942 Tagged_Conversion : declare
8943 Actual_Op_Typ : Entity_Id;
8944 Actual_Targ_Typ : Entity_Id;
8945 Make_Conversion : Boolean := False;
8946 Root_Op_Typ : Entity_Id;
8948 procedure Make_Tag_Check (Targ_Typ : Entity_Id);
8949 -- Create a membership check to test whether Operand is a member
8950 -- of Targ_Typ. If the original Target_Type is an access, include
8951 -- a test for null value. The check is inserted at N.
8953 --------------------
8954 -- Make_Tag_Check --
8955 --------------------
8957 procedure Make_Tag_Check (Targ_Typ : Entity_Id) is
8962 -- [Constraint_Error
8963 -- when Operand /= null
8964 -- and then Operand.all not in Targ_Typ]
8966 if Is_Access_Type (Target_Type) then
8971 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
8972 Right_Opnd => Make_Null (Loc)),
8977 Make_Explicit_Dereference (Loc,
8978 Prefix => Duplicate_Subexpr_No_Checks (Operand)),
8979 Right_Opnd => New_Reference_To (Targ_Typ, Loc)));
8982 -- [Constraint_Error when Operand not in Targ_Typ]
8987 Left_Opnd => Duplicate_Subexpr_No_Checks (Operand),
8988 Right_Opnd => New_Reference_To (Targ_Typ, Loc));
8992 Make_Raise_Constraint_Error (Loc,
8994 Reason => CE_Tag_Check_Failed));
8997 -- Start of processing for Tagged_Conversion
9000 -- Handle entities from the limited view
9002 if Is_Access_Type (Operand_Type) then
9004 Available_View (Designated_Type (Operand_Type));
9006 Actual_Op_Typ := Operand_Type;
9009 if Is_Access_Type (Target_Type) then
9011 Available_View (Designated_Type (Target_Type));
9013 Actual_Targ_Typ := Target_Type;
9016 Root_Op_Typ := Root_Type (Actual_Op_Typ);
9018 -- Ada 2005 (AI-251): Handle interface type conversion
9020 if Is_Interface (Actual_Op_Typ) then
9021 Expand_Interface_Conversion (N, Is_Static => False);
9025 if not Tag_Checks_Suppressed (Actual_Targ_Typ) then
9027 -- Create a runtime tag check for a downward class-wide type
9030 if Is_Class_Wide_Type (Actual_Op_Typ)
9031 and then Actual_Op_Typ /= Actual_Targ_Typ
9032 and then Root_Op_Typ /= Actual_Targ_Typ
9033 and then Is_Ancestor (Root_Op_Typ, Actual_Targ_Typ,
9034 Use_Full_View => True)
9036 Make_Tag_Check (Class_Wide_Type (Actual_Targ_Typ));
9037 Make_Conversion := True;
9040 -- AI05-0073: If the result subtype of the function is defined
9041 -- by an access_definition designating a specific tagged type
9042 -- T, a check is made that the result value is null or the tag
9043 -- of the object designated by the result value identifies T.
9044 -- Constraint_Error is raised if this check fails.
9046 if Nkind (Parent (N)) = Sinfo.N_Return_Statement then
9049 Func_Typ : Entity_Id;
9052 -- Climb scope stack looking for the enclosing function
9054 Func := Current_Scope;
9055 while Present (Func)
9056 and then Ekind (Func) /= E_Function
9058 Func := Scope (Func);
9061 -- The function's return subtype must be defined using
9062 -- an access definition.
9064 if Nkind (Result_Definition (Parent (Func))) =
9067 Func_Typ := Directly_Designated_Type (Etype (Func));
9069 -- The return subtype denotes a specific tagged type,
9070 -- in other words, a non class-wide type.
9072 if Is_Tagged_Type (Func_Typ)
9073 and then not Is_Class_Wide_Type (Func_Typ)
9075 Make_Tag_Check (Actual_Targ_Typ);
9076 Make_Conversion := True;
9082 -- We have generated a tag check for either a class-wide type
9083 -- conversion or for AI05-0073.
9085 if Make_Conversion then
9090 Make_Unchecked_Type_Conversion (Loc,
9091 Subtype_Mark => New_Occurrence_Of (Target_Type, Loc),
9092 Expression => Relocate_Node (Expression (N)));
9094 Analyze_And_Resolve (N, Target_Type);
9098 end Tagged_Conversion;
9100 -- Case of other access type conversions
9102 elsif Is_Access_Type (Target_Type) then
9103 Apply_Constraint_Check (Operand, Target_Type);
9105 -- Case of conversions from a fixed-point type
9107 -- These conversions require special expansion and processing, found in
9108 -- the Exp_Fixd package. We ignore cases where Conversion_OK is set,
9109 -- since from a semantic point of view, these are simple integer
9110 -- conversions, which do not need further processing.
9112 elsif Is_Fixed_Point_Type (Operand_Type)
9113 and then not Conversion_OK (N)
9115 -- We should never see universal fixed at this case, since the
9116 -- expansion of the constituent divide or multiply should have
9117 -- eliminated the explicit mention of universal fixed.
9119 pragma Assert (Operand_Type /= Universal_Fixed);
9121 -- Check for special case of the conversion to universal real that
9122 -- occurs as a result of the use of a round attribute. In this case,
9123 -- the real type for the conversion is taken from the target type of
9124 -- the Round attribute and the result must be marked as rounded.
9126 if Target_Type = Universal_Real
9127 and then Nkind (Parent (N)) = N_Attribute_Reference
9128 and then Attribute_Name (Parent (N)) = Name_Round
9130 Set_Rounded_Result (N);
9131 Set_Etype (N, Etype (Parent (N)));
9134 -- Otherwise do correct fixed-conversion, but skip these if the
9135 -- Conversion_OK flag is set, because from a semantic point of view
9136 -- these are simple integer conversions needing no further processing
9137 -- (the backend will simply treat them as integers).
9139 if not Conversion_OK (N) then
9140 if Is_Fixed_Point_Type (Etype (N)) then
9141 Expand_Convert_Fixed_To_Fixed (N);
9144 elsif Is_Integer_Type (Etype (N)) then
9145 Expand_Convert_Fixed_To_Integer (N);
9148 pragma Assert (Is_Floating_Point_Type (Etype (N)));
9149 Expand_Convert_Fixed_To_Float (N);
9154 -- Case of conversions to a fixed-point type
9156 -- These conversions require special expansion and processing, found in
9157 -- the Exp_Fixd package. Again, ignore cases where Conversion_OK is set,
9158 -- since from a semantic point of view, these are simple integer
9159 -- conversions, which do not need further processing.
9161 elsif Is_Fixed_Point_Type (Target_Type)
9162 and then not Conversion_OK (N)
9164 if Is_Integer_Type (Operand_Type) then
9165 Expand_Convert_Integer_To_Fixed (N);
9168 pragma Assert (Is_Floating_Point_Type (Operand_Type));
9169 Expand_Convert_Float_To_Fixed (N);
9173 -- Case of float-to-integer conversions
9175 -- We also handle float-to-fixed conversions with Conversion_OK set
9176 -- since semantically the fixed-point target is treated as though it
9177 -- were an integer in such cases.
9179 elsif Is_Floating_Point_Type (Operand_Type)
9181 (Is_Integer_Type (Target_Type)
9183 (Is_Fixed_Point_Type (Target_Type) and then Conversion_OK (N)))
9185 -- One more check here, gcc is still not able to do conversions of
9186 -- this type with proper overflow checking, and so gigi is doing an
9187 -- approximation of what is required by doing floating-point compares
9188 -- with the end-point. But that can lose precision in some cases, and
9189 -- give a wrong result. Converting the operand to Universal_Real is
9190 -- helpful, but still does not catch all cases with 64-bit integers
9191 -- on targets with only 64-bit floats.
9193 -- The above comment seems obsoleted by Apply_Float_Conversion_Check
9194 -- Can this code be removed ???
9196 if Do_Range_Check (Operand) then
9198 Make_Type_Conversion (Loc,
9200 New_Occurrence_Of (Universal_Real, Loc),
9202 Relocate_Node (Operand)));
9204 Set_Etype (Operand, Universal_Real);
9205 Enable_Range_Check (Operand);
9206 Set_Do_Range_Check (Expression (Operand), False);
9209 -- Case of array conversions
9211 -- Expansion of array conversions, add required length/range checks but
9212 -- only do this if there is no change of representation. For handling of
9213 -- this case, see Handle_Changed_Representation.
9215 elsif Is_Array_Type (Target_Type) then
9216 if Is_Constrained (Target_Type) then
9217 Apply_Length_Check (Operand, Target_Type);
9219 Apply_Range_Check (Operand, Target_Type);
9222 Handle_Changed_Representation;
9224 -- Case of conversions of discriminated types
9226 -- Add required discriminant checks if target is constrained. Again this
9227 -- change is skipped if we have a change of representation.
9229 elsif Has_Discriminants (Target_Type)
9230 and then Is_Constrained (Target_Type)
9232 Apply_Discriminant_Check (Operand, Target_Type);
9233 Handle_Changed_Representation;
9235 -- Case of all other record conversions. The only processing required
9236 -- is to check for a change of representation requiring the special
9237 -- assignment processing.
9239 elsif Is_Record_Type (Target_Type) then
9241 -- Ada 2005 (AI-216): Program_Error is raised when converting from
9242 -- a derived Unchecked_Union type to an unconstrained type that is
9243 -- not Unchecked_Union if the operand lacks inferable discriminants.
9245 if Is_Derived_Type (Operand_Type)
9246 and then Is_Unchecked_Union (Base_Type (Operand_Type))
9247 and then not Is_Constrained (Target_Type)
9248 and then not Is_Unchecked_Union (Base_Type (Target_Type))
9249 and then not Has_Inferable_Discriminants (Operand)
9251 -- To prevent Gigi from generating illegal code, we generate a
9252 -- Program_Error node, but we give it the target type of the
9256 PE : constant Node_Id := Make_Raise_Program_Error (Loc,
9257 Reason => PE_Unchecked_Union_Restriction);
9260 Set_Etype (PE, Target_Type);
9265 Handle_Changed_Representation;
9268 -- Case of conversions of enumeration types
9270 elsif Is_Enumeration_Type (Target_Type) then
9272 -- Special processing is required if there is a change of
9273 -- representation (from enumeration representation clauses).
9275 if not Same_Representation (Target_Type, Operand_Type) then
9277 -- Convert: x(y) to x'val (ytyp'val (y))
9280 Make_Attribute_Reference (Loc,
9281 Prefix => New_Occurrence_Of (Target_Type, Loc),
9282 Attribute_Name => Name_Val,
9283 Expressions => New_List (
9284 Make_Attribute_Reference (Loc,
9285 Prefix => New_Occurrence_Of (Operand_Type, Loc),
9286 Attribute_Name => Name_Pos,
9287 Expressions => New_List (Operand)))));
9289 Analyze_And_Resolve (N, Target_Type);
9292 -- Case of conversions to floating-point
9294 elsif Is_Floating_Point_Type (Target_Type) then
9298 -- At this stage, either the conversion node has been transformed into
9299 -- some other equivalent expression, or left as a conversion that can be
9300 -- handled by Gigi, in the following cases:
9302 -- Conversions with no change of representation or type
9304 -- Numeric conversions involving integer, floating- and fixed-point
9305 -- values. Fixed-point values are allowed only if Conversion_OK is
9306 -- set, i.e. if the fixed-point values are to be treated as integers.
9308 -- No other conversions should be passed to Gigi
9310 -- Check: are these rules stated in sinfo??? if so, why restate here???
9312 -- The only remaining step is to generate a range check if we still have
9313 -- a type conversion at this stage and Do_Range_Check is set. For now we
9314 -- do this only for conversions of discrete types.
9316 if Nkind (N) = N_Type_Conversion
9317 and then Is_Discrete_Type (Etype (N))
9320 Expr : constant Node_Id := Expression (N);
9325 if Do_Range_Check (Expr)
9326 and then Is_Discrete_Type (Etype (Expr))
9328 Set_Do_Range_Check (Expr, False);
9330 -- Before we do a range check, we have to deal with treating a
9331 -- fixed-point operand as an integer. The way we do this is
9332 -- simply to do an unchecked conversion to an appropriate
9333 -- integer type large enough to hold the result.
9335 -- This code is not active yet, because we are only dealing
9336 -- with discrete types so far ???
9338 if Nkind (Expr) in N_Has_Treat_Fixed_As_Integer
9339 and then Treat_Fixed_As_Integer (Expr)
9341 Ftyp := Base_Type (Etype (Expr));
9343 if Esize (Ftyp) >= Esize (Standard_Integer) then
9344 Ityp := Standard_Long_Long_Integer;
9346 Ityp := Standard_Integer;
9349 Rewrite (Expr, Unchecked_Convert_To (Ityp, Expr));
9352 -- Reset overflow flag, since the range check will include
9353 -- dealing with possible overflow, and generate the check. If
9354 -- Address is either a source type or target type, suppress
9355 -- range check to avoid typing anomalies when it is a visible
9358 Set_Do_Overflow_Check (N, False);
9359 if not Is_Descendent_Of_Address (Etype (Expr))
9360 and then not Is_Descendent_Of_Address (Target_Type)
9362 Generate_Range_Check
9363 (Expr, Target_Type, CE_Range_Check_Failed);
9369 -- Final step, if the result is a type conversion involving Vax_Float
9370 -- types, then it is subject for further special processing.
9372 if Nkind (N) = N_Type_Conversion
9373 and then (Vax_Float (Operand_Type) or else Vax_Float (Target_Type))
9375 Expand_Vax_Conversion (N);
9379 -- Here at end of processing
9382 -- Apply predicate check if required. Note that we can't just call
9383 -- Apply_Predicate_Check here, because the type looks right after
9384 -- the conversion and it would omit the check. The Comes_From_Source
9385 -- guard is necessary to prevent infinite recursions when we generate
9386 -- internal conversions for the purpose of checking predicates.
9388 if Present (Predicate_Function (Target_Type))
9389 and then Target_Type /= Operand_Type
9390 and then Comes_From_Source (N)
9393 New_Expr : constant Node_Id := Duplicate_Subexpr (N);
9396 -- Avoid infinite recursion on the subsequent expansion of
9397 -- of the copy of the original type conversion.
9399 Set_Comes_From_Source (New_Expr, False);
9400 Insert_Action (N, Make_Predicate_Check (Target_Type, New_Expr));
9403 end Expand_N_Type_Conversion;
9405 -----------------------------------
9406 -- Expand_N_Unchecked_Expression --
9407 -----------------------------------
9409 -- Remove the unchecked expression node from the tree. Its job was simply
9410 -- to make sure that its constituent expression was handled with checks
9411 -- off, and now that that is done, we can remove it from the tree, and
9412 -- indeed must, since Gigi does not expect to see these nodes.
9414 procedure Expand_N_Unchecked_Expression (N : Node_Id) is
9415 Exp : constant Node_Id := Expression (N);
9417 Set_Assignment_OK (Exp, Assignment_OK (N) or else Assignment_OK (Exp));
9419 end Expand_N_Unchecked_Expression;
9421 ----------------------------------------
9422 -- Expand_N_Unchecked_Type_Conversion --
9423 ----------------------------------------
9425 -- If this cannot be handled by Gigi and we haven't already made a
9426 -- temporary for it, do it now.
9428 procedure Expand_N_Unchecked_Type_Conversion (N : Node_Id) is
9429 Target_Type : constant Entity_Id := Etype (N);
9430 Operand : constant Node_Id := Expression (N);
9431 Operand_Type : constant Entity_Id := Etype (Operand);
9434 -- Nothing at all to do if conversion is to the identical type so remove
9435 -- the conversion completely, it is useless, except that it may carry
9436 -- an Assignment_OK indication which must be propagated to the operand.
9438 if Operand_Type = Target_Type then
9440 -- Code duplicates Expand_N_Unchecked_Expression above, factor???
9442 if Assignment_OK (N) then
9443 Set_Assignment_OK (Operand);
9446 Rewrite (N, Relocate_Node (Operand));
9450 -- If we have a conversion of a compile time known value to a target
9451 -- type and the value is in range of the target type, then we can simply
9452 -- replace the construct by an integer literal of the correct type. We
9453 -- only apply this to integer types being converted. Possibly it may
9454 -- apply in other cases, but it is too much trouble to worry about.
9456 -- Note that we do not do this transformation if the Kill_Range_Check
9457 -- flag is set, since then the value may be outside the expected range.
9458 -- This happens in the Normalize_Scalars case.
9460 -- We also skip this if either the target or operand type is biased
9461 -- because in this case, the unchecked conversion is supposed to
9462 -- preserve the bit pattern, not the integer value.
9464 if Is_Integer_Type (Target_Type)
9465 and then not Has_Biased_Representation (Target_Type)
9466 and then Is_Integer_Type (Operand_Type)
9467 and then not Has_Biased_Representation (Operand_Type)
9468 and then Compile_Time_Known_Value (Operand)
9469 and then not Kill_Range_Check (N)
9472 Val : constant Uint := Expr_Value (Operand);
9475 if Compile_Time_Known_Value (Type_Low_Bound (Target_Type))
9477 Compile_Time_Known_Value (Type_High_Bound (Target_Type))
9479 Val >= Expr_Value (Type_Low_Bound (Target_Type))
9481 Val <= Expr_Value (Type_High_Bound (Target_Type))
9483 Rewrite (N, Make_Integer_Literal (Sloc (N), Val));
9485 -- If Address is the target type, just set the type to avoid a
9486 -- spurious type error on the literal when Address is a visible
9489 if Is_Descendent_Of_Address (Target_Type) then
9490 Set_Etype (N, Target_Type);
9492 Analyze_And_Resolve (N, Target_Type);
9500 -- Nothing to do if conversion is safe
9502 if Safe_Unchecked_Type_Conversion (N) then
9506 -- Otherwise force evaluation unless Assignment_OK flag is set (this
9507 -- flag indicates ??? -- more comments needed here)
9509 if Assignment_OK (N) then
9512 Force_Evaluation (N);
9514 end Expand_N_Unchecked_Type_Conversion;
9516 ----------------------------
9517 -- Expand_Record_Equality --
9518 ----------------------------
9520 -- For non-variant records, Equality is expanded when needed into:
9522 -- and then Lhs.Discr1 = Rhs.Discr1
9524 -- and then Lhs.Discrn = Rhs.Discrn
9525 -- and then Lhs.Cmp1 = Rhs.Cmp1
9527 -- and then Lhs.Cmpn = Rhs.Cmpn
9529 -- The expression is folded by the back-end for adjacent fields. This
9530 -- function is called for tagged record in only one occasion: for imple-
9531 -- menting predefined primitive equality (see Predefined_Primitives_Bodies)
9532 -- otherwise the primitive "=" is used directly.
9534 function Expand_Record_Equality
9539 Bodies : List_Id) return Node_Id
9541 Loc : constant Source_Ptr := Sloc (Nod);
9546 First_Time : Boolean := True;
9548 function Suitable_Element (C : Entity_Id) return Entity_Id;
9549 -- Return the first field to compare beginning with C, skipping the
9550 -- inherited components.
9552 ----------------------
9553 -- Suitable_Element --
9554 ----------------------
9556 function Suitable_Element (C : Entity_Id) return Entity_Id is
9561 elsif Ekind (C) /= E_Discriminant
9562 and then Ekind (C) /= E_Component
9564 return Suitable_Element (Next_Entity (C));
9566 elsif Is_Tagged_Type (Typ)
9567 and then C /= Original_Record_Component (C)
9569 return Suitable_Element (Next_Entity (C));
9571 elsif Chars (C) = Name_uTag then
9572 return Suitable_Element (Next_Entity (C));
9574 -- The .NET/JVM version of type Root_Controlled contains two fields
9575 -- which should not be considered part of the object. To achieve
9576 -- proper equiality between two controlled objects on .NET/JVM, skip
9577 -- field _parent whenever it is of type Root_Controlled.
9579 elsif Chars (C) = Name_uParent
9580 and then VM_Target /= No_VM
9581 and then Etype (C) = RTE (RE_Root_Controlled)
9583 return Suitable_Element (Next_Entity (C));
9585 elsif Is_Interface (Etype (C)) then
9586 return Suitable_Element (Next_Entity (C));
9591 end Suitable_Element;
9593 -- Start of processing for Expand_Record_Equality
9596 -- Generates the following code: (assuming that Typ has one Discr and
9597 -- component C2 is also a record)
9600 -- and then Lhs.Discr1 = Rhs.Discr1
9601 -- and then Lhs.C1 = Rhs.C1
9602 -- and then Lhs.C2.C1=Rhs.C2.C1 and then ... Lhs.C2.Cn=Rhs.C2.Cn
9604 -- and then Lhs.Cmpn = Rhs.Cmpn
9606 Result := New_Reference_To (Standard_True, Loc);
9607 C := Suitable_Element (First_Entity (Typ));
9608 while Present (C) loop
9616 First_Time := False;
9620 New_Lhs := New_Copy_Tree (Lhs);
9621 New_Rhs := New_Copy_Tree (Rhs);
9625 Expand_Composite_Equality (Nod, Etype (C),
9627 Make_Selected_Component (Loc,
9629 Selector_Name => New_Reference_To (C, Loc)),
9631 Make_Selected_Component (Loc,
9633 Selector_Name => New_Reference_To (C, Loc)),
9636 -- If some (sub)component is an unchecked_union, the whole
9637 -- operation will raise program error.
9639 if Nkind (Check) = N_Raise_Program_Error then
9641 Set_Etype (Result, Standard_Boolean);
9646 Left_Opnd => Result,
9647 Right_Opnd => Check);
9651 C := Suitable_Element (Next_Entity (C));
9655 end Expand_Record_Equality;
9657 ---------------------------
9658 -- Expand_Set_Membership --
9659 ---------------------------
9661 procedure Expand_Set_Membership (N : Node_Id) is
9662 Lop : constant Node_Id := Left_Opnd (N);
9666 function Make_Cond (Alt : Node_Id) return Node_Id;
9667 -- If the alternative is a subtype mark, create a simple membership
9668 -- test. Otherwise create an equality test for it.
9674 function Make_Cond (Alt : Node_Id) return Node_Id is
9676 L : constant Node_Id := New_Copy (Lop);
9677 R : constant Node_Id := Relocate_Node (Alt);
9680 if (Is_Entity_Name (Alt) and then Is_Type (Entity (Alt)))
9681 or else Nkind (Alt) = N_Range
9684 Make_In (Sloc (Alt),
9689 Make_Op_Eq (Sloc (Alt),
9697 -- Start of processing for Expand_Set_Membership
9700 Remove_Side_Effects (Lop);
9702 Alt := Last (Alternatives (N));
9703 Res := Make_Cond (Alt);
9706 while Present (Alt) loop
9708 Make_Or_Else (Sloc (Alt),
9709 Left_Opnd => Make_Cond (Alt),
9715 Analyze_And_Resolve (N, Standard_Boolean);
9716 end Expand_Set_Membership;
9718 -----------------------------------
9719 -- Expand_Short_Circuit_Operator --
9720 -----------------------------------
9722 -- Deal with special expansion if actions are present for the right operand
9723 -- and deal with optimizing case of arguments being True or False. We also
9724 -- deal with the special case of non-standard boolean values.
9726 procedure Expand_Short_Circuit_Operator (N : Node_Id) is
9727 Loc : constant Source_Ptr := Sloc (N);
9728 Typ : constant Entity_Id := Etype (N);
9729 Left : constant Node_Id := Left_Opnd (N);
9730 Right : constant Node_Id := Right_Opnd (N);
9731 LocR : constant Source_Ptr := Sloc (Right);
9734 Shortcut_Value : constant Boolean := Nkind (N) = N_Or_Else;
9735 Shortcut_Ent : constant Entity_Id := Boolean_Literals (Shortcut_Value);
9736 -- If Left = Shortcut_Value then Right need not be evaluated
9738 function Make_Test_Expr (Opnd : Node_Id) return Node_Id;
9739 -- For Opnd a boolean expression, return a Boolean expression equivalent
9740 -- to Opnd /= Shortcut_Value.
9742 --------------------
9743 -- Make_Test_Expr --
9744 --------------------
9746 function Make_Test_Expr (Opnd : Node_Id) return Node_Id is
9748 if Shortcut_Value then
9749 return Make_Op_Not (Sloc (Opnd), Opnd);
9756 -- Entity for a temporary variable holding the value of the operator,
9757 -- used for expansion in the case where actions are present.
9759 -- Start of processing for Expand_Short_Circuit_Operator
9762 -- Deal with non-standard booleans
9764 if Is_Boolean_Type (Typ) then
9765 Adjust_Condition (Left);
9766 Adjust_Condition (Right);
9767 Set_Etype (N, Standard_Boolean);
9770 -- Check for cases where left argument is known to be True or False
9772 if Compile_Time_Known_Value (Left) then
9774 -- Mark SCO for left condition as compile time known
9776 if Generate_SCO and then Comes_From_Source (Left) then
9777 Set_SCO_Condition (Left, Expr_Value_E (Left) = Standard_True);
9780 -- Rewrite True AND THEN Right / False OR ELSE Right to Right.
9781 -- Any actions associated with Right will be executed unconditionally
9782 -- and can thus be inserted into the tree unconditionally.
9784 if Expr_Value_E (Left) /= Shortcut_Ent then
9785 if Present (Actions (N)) then
9786 Insert_Actions (N, Actions (N));
9791 -- Rewrite False AND THEN Right / True OR ELSE Right to Left.
9792 -- In this case we can forget the actions associated with Right,
9793 -- since they will never be executed.
9796 Kill_Dead_Code (Right);
9797 Kill_Dead_Code (Actions (N));
9798 Rewrite (N, New_Occurrence_Of (Shortcut_Ent, Loc));
9801 Adjust_Result_Type (N, Typ);
9805 -- If Actions are present for the right operand, we have to do some
9806 -- special processing. We can't just let these actions filter back into
9807 -- code preceding the short circuit (which is what would have happened
9808 -- if we had not trapped them in the short-circuit form), since they
9809 -- must only be executed if the right operand of the short circuit is
9810 -- executed and not otherwise.
9812 -- the temporary variable C.
9814 if Present (Actions (N)) then
9815 Actlist := Actions (N);
9817 -- The old approach is to expand:
9819 -- left AND THEN right
9823 -- C : Boolean := False;
9831 -- and finally rewrite the operator into a reference to C. Similarly
9832 -- for left OR ELSE right, with negated values. Note that this
9833 -- rewrite causes some difficulties for coverage analysis because
9834 -- of the introduction of the new variable C, which obscures the
9835 -- structure of the test.
9837 -- We use this "old approach" if use of N_Expression_With_Actions
9838 -- is False (see description in Opt of when this is or is not set).
9840 if not Use_Expression_With_Actions then
9841 Op_Var := Make_Temporary (Loc, 'C', Related_Node => N);
9844 Make_Object_Declaration (Loc,
9845 Defining_Identifier =>
9847 Object_Definition =>
9848 New_Occurrence_Of (Standard_Boolean, Loc),
9850 New_Occurrence_Of (Shortcut_Ent, Loc)));
9853 Make_Implicit_If_Statement (Right,
9854 Condition => Make_Test_Expr (Right),
9855 Then_Statements => New_List (
9856 Make_Assignment_Statement (LocR,
9857 Name => New_Occurrence_Of (Op_Var, LocR),
9860 (Boolean_Literals (not Shortcut_Value), LocR)))));
9863 Make_Implicit_If_Statement (Left,
9864 Condition => Make_Test_Expr (Left),
9865 Then_Statements => Actlist));
9867 Rewrite (N, New_Occurrence_Of (Op_Var, Loc));
9868 Analyze_And_Resolve (N, Standard_Boolean);
9870 -- The new approach, activated for now by the use of debug flag
9871 -- -gnatd.X is to use the new Expression_With_Actions node for the
9872 -- right operand of the short-circuit form. This should solve the
9873 -- traceability problems for coverage analysis.
9877 Make_Expression_With_Actions (LocR,
9878 Expression => Relocate_Node (Right),
9879 Actions => Actlist));
9880 Set_Actions (N, No_List);
9881 Analyze_And_Resolve (Right, Standard_Boolean);
9884 Adjust_Result_Type (N, Typ);
9888 -- No actions present, check for cases of right argument True/False
9890 if Compile_Time_Known_Value (Right) then
9892 -- Mark SCO for left condition as compile time known
9894 if Generate_SCO and then Comes_From_Source (Right) then
9895 Set_SCO_Condition (Right, Expr_Value_E (Right) = Standard_True);
9898 -- Change (Left and then True), (Left or else False) to Left.
9899 -- Note that we know there are no actions associated with the right
9900 -- operand, since we just checked for this case above.
9902 if Expr_Value_E (Right) /= Shortcut_Ent then
9905 -- Change (Left and then False), (Left or else True) to Right,
9906 -- making sure to preserve any side effects associated with the Left
9910 Remove_Side_Effects (Left);
9911 Rewrite (N, New_Occurrence_Of (Shortcut_Ent, Loc));
9915 Adjust_Result_Type (N, Typ);
9916 end Expand_Short_Circuit_Operator;
9918 -------------------------------------
9919 -- Fixup_Universal_Fixed_Operation --
9920 -------------------------------------
9922 procedure Fixup_Universal_Fixed_Operation (N : Node_Id) is
9923 Conv : constant Node_Id := Parent (N);
9926 -- We must have a type conversion immediately above us
9928 pragma Assert (Nkind (Conv) = N_Type_Conversion);
9930 -- Normally the type conversion gives our target type. The exception
9931 -- occurs in the case of the Round attribute, where the conversion
9932 -- will be to universal real, and our real type comes from the Round
9933 -- attribute (as well as an indication that we must round the result)
9935 if Nkind (Parent (Conv)) = N_Attribute_Reference
9936 and then Attribute_Name (Parent (Conv)) = Name_Round
9938 Set_Etype (N, Etype (Parent (Conv)));
9939 Set_Rounded_Result (N);
9941 -- Normal case where type comes from conversion above us
9944 Set_Etype (N, Etype (Conv));
9946 end Fixup_Universal_Fixed_Operation;
9948 ---------------------------------
9949 -- Has_Inferable_Discriminants --
9950 ---------------------------------
9952 function Has_Inferable_Discriminants (N : Node_Id) return Boolean is
9954 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean;
9955 -- Determines whether the left-most prefix of a selected component is a
9956 -- formal parameter in a subprogram. Assumes N is a selected component.
9958 --------------------------------
9959 -- Prefix_Is_Formal_Parameter --
9960 --------------------------------
9962 function Prefix_Is_Formal_Parameter (N : Node_Id) return Boolean is
9963 Sel_Comp : Node_Id := N;
9966 -- Move to the left-most prefix by climbing up the tree
9968 while Present (Parent (Sel_Comp))
9969 and then Nkind (Parent (Sel_Comp)) = N_Selected_Component
9971 Sel_Comp := Parent (Sel_Comp);
9974 return Ekind (Entity (Prefix (Sel_Comp))) in Formal_Kind;
9975 end Prefix_Is_Formal_Parameter;
9977 -- Start of processing for Has_Inferable_Discriminants
9980 -- For identifiers and indexed components, it is sufficient to have a
9981 -- constrained Unchecked_Union nominal subtype.
9983 if Nkind_In (N, N_Identifier, N_Indexed_Component) then
9984 return Is_Unchecked_Union (Base_Type (Etype (N)))
9986 Is_Constrained (Etype (N));
9988 -- For selected components, the subtype of the selector must be a
9989 -- constrained Unchecked_Union. If the component is subject to a
9990 -- per-object constraint, then the enclosing object must have inferable
9993 elsif Nkind (N) = N_Selected_Component then
9994 if Has_Per_Object_Constraint (Entity (Selector_Name (N))) then
9996 -- A small hack. If we have a per-object constrained selected
9997 -- component of a formal parameter, return True since we do not
9998 -- know the actual parameter association yet.
10000 if Prefix_Is_Formal_Parameter (N) then
10004 -- Otherwise, check the enclosing object and the selector
10006 return Has_Inferable_Discriminants (Prefix (N))
10008 Has_Inferable_Discriminants (Selector_Name (N));
10011 -- The call to Has_Inferable_Discriminants will determine whether
10012 -- the selector has a constrained Unchecked_Union nominal type.
10014 return Has_Inferable_Discriminants (Selector_Name (N));
10016 -- A qualified expression has inferable discriminants if its subtype
10017 -- mark is a constrained Unchecked_Union subtype.
10019 elsif Nkind (N) = N_Qualified_Expression then
10020 return Is_Unchecked_Union (Subtype_Mark (N))
10022 Is_Constrained (Subtype_Mark (N));
10027 end Has_Inferable_Discriminants;
10029 -------------------------------
10030 -- Insert_Dereference_Action --
10031 -------------------------------
10033 procedure Insert_Dereference_Action (N : Node_Id) is
10034 Loc : constant Source_Ptr := Sloc (N);
10035 Typ : constant Entity_Id := Etype (N);
10036 Pool : constant Entity_Id := Associated_Storage_Pool (Typ);
10037 Pnod : constant Node_Id := Parent (N);
10039 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean;
10040 -- Return true if type of P is derived from Checked_Pool;
10042 -----------------------------
10043 -- Is_Checked_Storage_Pool --
10044 -----------------------------
10046 function Is_Checked_Storage_Pool (P : Entity_Id) return Boolean is
10055 while T /= Etype (T) loop
10056 if Is_RTE (T, RE_Checked_Pool) then
10064 end Is_Checked_Storage_Pool;
10066 -- Start of processing for Insert_Dereference_Action
10069 pragma Assert (Nkind (Pnod) = N_Explicit_Dereference);
10071 if not (Is_Checked_Storage_Pool (Pool)
10072 and then Comes_From_Source (Original_Node (Pnod)))
10078 Make_Procedure_Call_Statement (Loc,
10079 Name => New_Reference_To (
10080 Find_Prim_Op (Etype (Pool), Name_Dereference), Loc),
10082 Parameter_Associations => New_List (
10086 New_Reference_To (Pool, Loc),
10088 -- Storage_Address. We use the attribute Pool_Address, which uses
10089 -- the pointer itself to find the address of the object, and which
10090 -- handles unconstrained arrays properly by computing the address
10091 -- of the template. i.e. the correct address of the corresponding
10094 Make_Attribute_Reference (Loc,
10095 Prefix => Duplicate_Subexpr_Move_Checks (N),
10096 Attribute_Name => Name_Pool_Address),
10098 -- Size_In_Storage_Elements
10100 Make_Op_Divide (Loc,
10102 Make_Attribute_Reference (Loc,
10104 Make_Explicit_Dereference (Loc,
10105 Duplicate_Subexpr_Move_Checks (N)),
10106 Attribute_Name => Name_Size),
10108 Make_Integer_Literal (Loc, System_Storage_Unit)),
10112 Make_Attribute_Reference (Loc,
10114 Make_Explicit_Dereference (Loc,
10115 Duplicate_Subexpr_Move_Checks (N)),
10116 Attribute_Name => Name_Alignment))));
10119 when RE_Not_Available =>
10121 end Insert_Dereference_Action;
10123 --------------------------------
10124 -- Integer_Promotion_Possible --
10125 --------------------------------
10127 function Integer_Promotion_Possible (N : Node_Id) return Boolean is
10128 Operand : constant Node_Id := Expression (N);
10129 Operand_Type : constant Entity_Id := Etype (Operand);
10130 Root_Operand_Type : constant Entity_Id := Root_Type (Operand_Type);
10133 pragma Assert (Nkind (N) = N_Type_Conversion);
10137 -- We only do the transformation for source constructs. We assume
10138 -- that the expander knows what it is doing when it generates code.
10140 Comes_From_Source (N)
10142 -- If the operand type is Short_Integer or Short_Short_Integer,
10143 -- then we will promote to Integer, which is available on all
10144 -- targets, and is sufficient to ensure no intermediate overflow.
10145 -- Furthermore it is likely to be as efficient or more efficient
10146 -- than using the smaller type for the computation so we do this
10147 -- unconditionally.
10150 (Root_Operand_Type = Base_Type (Standard_Short_Integer)
10152 Root_Operand_Type = Base_Type (Standard_Short_Short_Integer))
10154 -- Test for interesting operation, which includes addition,
10155 -- division, exponentiation, multiplication, subtraction, absolute
10156 -- value and unary negation. Unary "+" is omitted since it is a
10157 -- no-op and thus can't overflow.
10159 and then Nkind_In (Operand, N_Op_Abs,
10166 end Integer_Promotion_Possible;
10168 ------------------------------
10169 -- Make_Array_Comparison_Op --
10170 ------------------------------
10172 -- This is a hand-coded expansion of the following generic function:
10175 -- type elem is (<>);
10176 -- type index is (<>);
10177 -- type a is array (index range <>) of elem;
10179 -- function Gnnn (X : a; Y: a) return boolean is
10180 -- J : index := Y'first;
10183 -- if X'length = 0 then
10186 -- elsif Y'length = 0 then
10190 -- for I in X'range loop
10191 -- if X (I) = Y (J) then
10192 -- if J = Y'last then
10195 -- J := index'succ (J);
10199 -- return X (I) > Y (J);
10203 -- return X'length > Y'length;
10207 -- Note that since we are essentially doing this expansion by hand, we
10208 -- do not need to generate an actual or formal generic part, just the
10209 -- instantiated function itself.
10211 function Make_Array_Comparison_Op
10213 Nod : Node_Id) return Node_Id
10215 Loc : constant Source_Ptr := Sloc (Nod);
10217 X : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uX);
10218 Y : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uY);
10219 I : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uI);
10220 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
10222 Index : constant Entity_Id := Base_Type (Etype (First_Index (Typ)));
10224 Loop_Statement : Node_Id;
10225 Loop_Body : Node_Id;
10227 Inner_If : Node_Id;
10228 Final_Expr : Node_Id;
10229 Func_Body : Node_Id;
10230 Func_Name : Entity_Id;
10236 -- if J = Y'last then
10239 -- J := index'succ (J);
10243 Make_Implicit_If_Statement (Nod,
10246 Left_Opnd => New_Reference_To (J, Loc),
10248 Make_Attribute_Reference (Loc,
10249 Prefix => New_Reference_To (Y, Loc),
10250 Attribute_Name => Name_Last)),
10252 Then_Statements => New_List (
10253 Make_Exit_Statement (Loc)),
10257 Make_Assignment_Statement (Loc,
10258 Name => New_Reference_To (J, Loc),
10260 Make_Attribute_Reference (Loc,
10261 Prefix => New_Reference_To (Index, Loc),
10262 Attribute_Name => Name_Succ,
10263 Expressions => New_List (New_Reference_To (J, Loc))))));
10265 -- if X (I) = Y (J) then
10268 -- return X (I) > Y (J);
10272 Make_Implicit_If_Statement (Nod,
10276 Make_Indexed_Component (Loc,
10277 Prefix => New_Reference_To (X, Loc),
10278 Expressions => New_List (New_Reference_To (I, Loc))),
10281 Make_Indexed_Component (Loc,
10282 Prefix => New_Reference_To (Y, Loc),
10283 Expressions => New_List (New_Reference_To (J, Loc)))),
10285 Then_Statements => New_List (Inner_If),
10287 Else_Statements => New_List (
10288 Make_Simple_Return_Statement (Loc,
10292 Make_Indexed_Component (Loc,
10293 Prefix => New_Reference_To (X, Loc),
10294 Expressions => New_List (New_Reference_To (I, Loc))),
10297 Make_Indexed_Component (Loc,
10298 Prefix => New_Reference_To (Y, Loc),
10299 Expressions => New_List (
10300 New_Reference_To (J, Loc)))))));
10302 -- for I in X'range loop
10307 Make_Implicit_Loop_Statement (Nod,
10308 Identifier => Empty,
10310 Iteration_Scheme =>
10311 Make_Iteration_Scheme (Loc,
10312 Loop_Parameter_Specification =>
10313 Make_Loop_Parameter_Specification (Loc,
10314 Defining_Identifier => I,
10315 Discrete_Subtype_Definition =>
10316 Make_Attribute_Reference (Loc,
10317 Prefix => New_Reference_To (X, Loc),
10318 Attribute_Name => Name_Range))),
10320 Statements => New_List (Loop_Body));
10322 -- if X'length = 0 then
10324 -- elsif Y'length = 0 then
10327 -- for ... loop ... end loop;
10328 -- return X'length > Y'length;
10332 Make_Attribute_Reference (Loc,
10333 Prefix => New_Reference_To (X, Loc),
10334 Attribute_Name => Name_Length);
10337 Make_Attribute_Reference (Loc,
10338 Prefix => New_Reference_To (Y, Loc),
10339 Attribute_Name => Name_Length);
10343 Left_Opnd => Length1,
10344 Right_Opnd => Length2);
10347 Make_Implicit_If_Statement (Nod,
10351 Make_Attribute_Reference (Loc,
10352 Prefix => New_Reference_To (X, Loc),
10353 Attribute_Name => Name_Length),
10355 Make_Integer_Literal (Loc, 0)),
10359 Make_Simple_Return_Statement (Loc,
10360 Expression => New_Reference_To (Standard_False, Loc))),
10362 Elsif_Parts => New_List (
10363 Make_Elsif_Part (Loc,
10367 Make_Attribute_Reference (Loc,
10368 Prefix => New_Reference_To (Y, Loc),
10369 Attribute_Name => Name_Length),
10371 Make_Integer_Literal (Loc, 0)),
10375 Make_Simple_Return_Statement (Loc,
10376 Expression => New_Reference_To (Standard_True, Loc))))),
10378 Else_Statements => New_List (
10380 Make_Simple_Return_Statement (Loc,
10381 Expression => Final_Expr)));
10385 Formals := New_List (
10386 Make_Parameter_Specification (Loc,
10387 Defining_Identifier => X,
10388 Parameter_Type => New_Reference_To (Typ, Loc)),
10390 Make_Parameter_Specification (Loc,
10391 Defining_Identifier => Y,
10392 Parameter_Type => New_Reference_To (Typ, Loc)));
10394 -- function Gnnn (...) return boolean is
10395 -- J : index := Y'first;
10400 Func_Name := Make_Temporary (Loc, 'G');
10403 Make_Subprogram_Body (Loc,
10405 Make_Function_Specification (Loc,
10406 Defining_Unit_Name => Func_Name,
10407 Parameter_Specifications => Formals,
10408 Result_Definition => New_Reference_To (Standard_Boolean, Loc)),
10410 Declarations => New_List (
10411 Make_Object_Declaration (Loc,
10412 Defining_Identifier => J,
10413 Object_Definition => New_Reference_To (Index, Loc),
10415 Make_Attribute_Reference (Loc,
10416 Prefix => New_Reference_To (Y, Loc),
10417 Attribute_Name => Name_First))),
10419 Handled_Statement_Sequence =>
10420 Make_Handled_Sequence_Of_Statements (Loc,
10421 Statements => New_List (If_Stat)));
10424 end Make_Array_Comparison_Op;
10426 ---------------------------
10427 -- Make_Boolean_Array_Op --
10428 ---------------------------
10430 -- For logical operations on boolean arrays, expand in line the following,
10431 -- replacing 'and' with 'or' or 'xor' where needed:
10433 -- function Annn (A : typ; B: typ) return typ is
10436 -- for J in A'range loop
10437 -- C (J) := A (J) op B (J);
10442 -- Here typ is the boolean array type
10444 function Make_Boolean_Array_Op
10446 N : Node_Id) return Node_Id
10448 Loc : constant Source_Ptr := Sloc (N);
10450 A : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uA);
10451 B : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uB);
10452 C : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uC);
10453 J : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uJ);
10461 Func_Name : Entity_Id;
10462 Func_Body : Node_Id;
10463 Loop_Statement : Node_Id;
10467 Make_Indexed_Component (Loc,
10468 Prefix => New_Reference_To (A, Loc),
10469 Expressions => New_List (New_Reference_To (J, Loc)));
10472 Make_Indexed_Component (Loc,
10473 Prefix => New_Reference_To (B, Loc),
10474 Expressions => New_List (New_Reference_To (J, Loc)));
10477 Make_Indexed_Component (Loc,
10478 Prefix => New_Reference_To (C, Loc),
10479 Expressions => New_List (New_Reference_To (J, Loc)));
10481 if Nkind (N) = N_Op_And then
10485 Right_Opnd => B_J);
10487 elsif Nkind (N) = N_Op_Or then
10491 Right_Opnd => B_J);
10497 Right_Opnd => B_J);
10501 Make_Implicit_Loop_Statement (N,
10502 Identifier => Empty,
10504 Iteration_Scheme =>
10505 Make_Iteration_Scheme (Loc,
10506 Loop_Parameter_Specification =>
10507 Make_Loop_Parameter_Specification (Loc,
10508 Defining_Identifier => J,
10509 Discrete_Subtype_Definition =>
10510 Make_Attribute_Reference (Loc,
10511 Prefix => New_Reference_To (A, Loc),
10512 Attribute_Name => Name_Range))),
10514 Statements => New_List (
10515 Make_Assignment_Statement (Loc,
10517 Expression => Op)));
10519 Formals := New_List (
10520 Make_Parameter_Specification (Loc,
10521 Defining_Identifier => A,
10522 Parameter_Type => New_Reference_To (Typ, Loc)),
10524 Make_Parameter_Specification (Loc,
10525 Defining_Identifier => B,
10526 Parameter_Type => New_Reference_To (Typ, Loc)));
10528 Func_Name := Make_Temporary (Loc, 'A');
10529 Set_Is_Inlined (Func_Name);
10532 Make_Subprogram_Body (Loc,
10534 Make_Function_Specification (Loc,
10535 Defining_Unit_Name => Func_Name,
10536 Parameter_Specifications => Formals,
10537 Result_Definition => New_Reference_To (Typ, Loc)),
10539 Declarations => New_List (
10540 Make_Object_Declaration (Loc,
10541 Defining_Identifier => C,
10542 Object_Definition => New_Reference_To (Typ, Loc))),
10544 Handled_Statement_Sequence =>
10545 Make_Handled_Sequence_Of_Statements (Loc,
10546 Statements => New_List (
10548 Make_Simple_Return_Statement (Loc,
10549 Expression => New_Reference_To (C, Loc)))));
10552 end Make_Boolean_Array_Op;
10554 --------------------------------
10555 -- Optimize_Length_Comparison --
10556 --------------------------------
10558 procedure Optimize_Length_Comparison (N : Node_Id) is
10559 Loc : constant Source_Ptr := Sloc (N);
10560 Typ : constant Entity_Id := Etype (N);
10565 -- First and Last attribute reference nodes, which end up as left and
10566 -- right operands of the optimized result.
10569 -- True for comparison operand of zero
10572 -- Comparison operand, set only if Is_Zero is false
10575 -- Entity whose length is being compared
10578 -- Integer_Literal node for length attribute expression, or Empty
10579 -- if there is no such expression present.
10582 -- Type of array index to which 'Length is applied
10584 Op : Node_Kind := Nkind (N);
10585 -- Kind of comparison operator, gets flipped if operands backwards
10587 function Is_Optimizable (N : Node_Id) return Boolean;
10588 -- Tests N to see if it is an optimizable comparison value (defined as
10589 -- constant zero or one, or something else where the value is known to
10590 -- be positive and in the range of 32-bits, and where the corresponding
10591 -- Length value is also known to be 32-bits. If result is true, sets
10592 -- Is_Zero, Ityp, and Comp accordingly.
10594 function Is_Entity_Length (N : Node_Id) return Boolean;
10595 -- Tests if N is a length attribute applied to a simple entity. If so,
10596 -- returns True, and sets Ent to the entity, and Index to the integer
10597 -- literal provided as an attribute expression, or to Empty if none.
10598 -- Also returns True if the expression is a generated type conversion
10599 -- whose expression is of the desired form. This latter case arises
10600 -- when Apply_Universal_Integer_Attribute_Check installs a conversion
10601 -- to check for being in range, which is not needed in this context.
10602 -- Returns False if neither condition holds.
10604 function Prepare_64 (N : Node_Id) return Node_Id;
10605 -- Given a discrete expression, returns a Long_Long_Integer typed
10606 -- expression representing the underlying value of the expression.
10607 -- This is done with an unchecked conversion to the result type. We
10608 -- use unchecked conversion to handle the enumeration type case.
10610 ----------------------
10611 -- Is_Entity_Length --
10612 ----------------------
10614 function Is_Entity_Length (N : Node_Id) return Boolean is
10616 if Nkind (N) = N_Attribute_Reference
10617 and then Attribute_Name (N) = Name_Length
10618 and then Is_Entity_Name (Prefix (N))
10620 Ent := Entity (Prefix (N));
10622 if Present (Expressions (N)) then
10623 Index := First (Expressions (N));
10630 elsif Nkind (N) = N_Type_Conversion
10631 and then not Comes_From_Source (N)
10633 return Is_Entity_Length (Expression (N));
10638 end Is_Entity_Length;
10640 --------------------
10641 -- Is_Optimizable --
10642 --------------------
10644 function Is_Optimizable (N : Node_Id) return Boolean is
10652 if Compile_Time_Known_Value (N) then
10653 Val := Expr_Value (N);
10655 if Val = Uint_0 then
10660 elsif Val = Uint_1 then
10667 -- Here we have to make sure of being within 32-bits
10669 Determine_Range (N, OK, Lo, Hi, Assume_Valid => True);
10672 or else Lo < Uint_1
10673 or else Hi > UI_From_Int (Int'Last)
10678 -- Comparison value was within range, so now we must check the index
10679 -- value to make sure it is also within 32-bits.
10681 Indx := First_Index (Etype (Ent));
10683 if Present (Index) then
10684 for J in 2 .. UI_To_Int (Intval (Index)) loop
10689 Ityp := Etype (Indx);
10691 if Esize (Ityp) > 32 then
10698 end Is_Optimizable;
10704 function Prepare_64 (N : Node_Id) return Node_Id is
10706 return Unchecked_Convert_To (Standard_Long_Long_Integer, N);
10709 -- Start of processing for Optimize_Length_Comparison
10712 -- Nothing to do if not a comparison
10714 if Op not in N_Op_Compare then
10718 -- Nothing to do if special -gnatd.P debug flag set
10720 if Debug_Flag_Dot_PP then
10724 -- Ent'Length op 0/1
10726 if Is_Entity_Length (Left_Opnd (N))
10727 and then Is_Optimizable (Right_Opnd (N))
10731 -- 0/1 op Ent'Length
10733 elsif Is_Entity_Length (Right_Opnd (N))
10734 and then Is_Optimizable (Left_Opnd (N))
10736 -- Flip comparison to opposite sense
10739 when N_Op_Lt => Op := N_Op_Gt;
10740 when N_Op_Le => Op := N_Op_Ge;
10741 when N_Op_Gt => Op := N_Op_Lt;
10742 when N_Op_Ge => Op := N_Op_Le;
10743 when others => null;
10746 -- Else optimization not possible
10752 -- Fall through if we will do the optimization
10754 -- Cases to handle:
10756 -- X'Length = 0 => X'First > X'Last
10757 -- X'Length = 1 => X'First = X'Last
10758 -- X'Length = n => X'First + (n - 1) = X'Last
10760 -- X'Length /= 0 => X'First <= X'Last
10761 -- X'Length /= 1 => X'First /= X'Last
10762 -- X'Length /= n => X'First + (n - 1) /= X'Last
10764 -- X'Length >= 0 => always true, warn
10765 -- X'Length >= 1 => X'First <= X'Last
10766 -- X'Length >= n => X'First + (n - 1) <= X'Last
10768 -- X'Length > 0 => X'First <= X'Last
10769 -- X'Length > 1 => X'First < X'Last
10770 -- X'Length > n => X'First + (n - 1) < X'Last
10772 -- X'Length <= 0 => X'First > X'Last (warn, could be =)
10773 -- X'Length <= 1 => X'First >= X'Last
10774 -- X'Length <= n => X'First + (n - 1) >= X'Last
10776 -- X'Length < 0 => always false (warn)
10777 -- X'Length < 1 => X'First > X'Last
10778 -- X'Length < n => X'First + (n - 1) > X'Last
10780 -- Note: for the cases of n (not constant 0,1), we require that the
10781 -- corresponding index type be integer or shorter (i.e. not 64-bit),
10782 -- and the same for the comparison value. Then we do the comparison
10783 -- using 64-bit arithmetic (actually long long integer), so that we
10784 -- cannot have overflow intefering with the result.
10786 -- First deal with warning cases
10795 Convert_To (Typ, New_Occurrence_Of (Standard_True, Loc)));
10796 Analyze_And_Resolve (N, Typ);
10797 Warn_On_Known_Condition (N);
10804 Convert_To (Typ, New_Occurrence_Of (Standard_False, Loc)));
10805 Analyze_And_Resolve (N, Typ);
10806 Warn_On_Known_Condition (N);
10810 if Constant_Condition_Warnings
10811 and then Comes_From_Source (Original_Node (N))
10813 Error_Msg_N ("could replace by ""'=""?", N);
10823 -- Build the First reference we will use
10826 Make_Attribute_Reference (Loc,
10827 Prefix => New_Occurrence_Of (Ent, Loc),
10828 Attribute_Name => Name_First);
10830 if Present (Index) then
10831 Set_Expressions (Left, New_List (New_Copy (Index)));
10834 -- If general value case, then do the addition of (n - 1), and
10835 -- also add the needed conversions to type Long_Long_Integer.
10837 if Present (Comp) then
10840 Left_Opnd => Prepare_64 (Left),
10842 Make_Op_Subtract (Loc,
10843 Left_Opnd => Prepare_64 (Comp),
10844 Right_Opnd => Make_Integer_Literal (Loc, 1)));
10847 -- Build the Last reference we will use
10850 Make_Attribute_Reference (Loc,
10851 Prefix => New_Occurrence_Of (Ent, Loc),
10852 Attribute_Name => Name_Last);
10854 if Present (Index) then
10855 Set_Expressions (Right, New_List (New_Copy (Index)));
10858 -- If general operand, convert Last reference to Long_Long_Integer
10860 if Present (Comp) then
10861 Right := Prepare_64 (Right);
10864 -- Check for cases to optimize
10866 -- X'Length = 0 => X'First > X'Last
10867 -- X'Length < 1 => X'First > X'Last
10868 -- X'Length < n => X'First + (n - 1) > X'Last
10870 if (Is_Zero and then Op = N_Op_Eq)
10871 or else (not Is_Zero and then Op = N_Op_Lt)
10876 Right_Opnd => Right);
10878 -- X'Length = 1 => X'First = X'Last
10879 -- X'Length = n => X'First + (n - 1) = X'Last
10881 elsif not Is_Zero and then Op = N_Op_Eq then
10885 Right_Opnd => Right);
10887 -- X'Length /= 0 => X'First <= X'Last
10888 -- X'Length > 0 => X'First <= X'Last
10890 elsif Is_Zero and (Op = N_Op_Ne or else Op = N_Op_Gt) then
10894 Right_Opnd => Right);
10896 -- X'Length /= 1 => X'First /= X'Last
10897 -- X'Length /= n => X'First + (n - 1) /= X'Last
10899 elsif not Is_Zero and then Op = N_Op_Ne then
10903 Right_Opnd => Right);
10905 -- X'Length >= 1 => X'First <= X'Last
10906 -- X'Length >= n => X'First + (n - 1) <= X'Last
10908 elsif not Is_Zero and then Op = N_Op_Ge then
10912 Right_Opnd => Right);
10914 -- X'Length > 1 => X'First < X'Last
10915 -- X'Length > n => X'First + (n = 1) < X'Last
10917 elsif not Is_Zero and then Op = N_Op_Gt then
10921 Right_Opnd => Right);
10923 -- X'Length <= 1 => X'First >= X'Last
10924 -- X'Length <= n => X'First + (n - 1) >= X'Last
10926 elsif not Is_Zero and then Op = N_Op_Le then
10930 Right_Opnd => Right);
10932 -- Should not happen at this stage
10935 raise Program_Error;
10938 -- Rewrite and finish up
10940 Rewrite (N, Result);
10941 Analyze_And_Resolve (N, Typ);
10943 end Optimize_Length_Comparison;
10945 ------------------------
10946 -- Rewrite_Comparison --
10947 ------------------------
10949 procedure Rewrite_Comparison (N : Node_Id) is
10950 Warning_Generated : Boolean := False;
10951 -- Set to True if first pass with Assume_Valid generates a warning in
10952 -- which case we skip the second pass to avoid warning overloaded.
10955 -- Set to Standard_True or Standard_False
10958 if Nkind (N) = N_Type_Conversion then
10959 Rewrite_Comparison (Expression (N));
10962 elsif Nkind (N) not in N_Op_Compare then
10966 -- Now start looking at the comparison in detail. We potentially go
10967 -- through this loop twice. The first time, Assume_Valid is set False
10968 -- in the call to Compile_Time_Compare. If this call results in a
10969 -- clear result of always True or Always False, that's decisive and
10970 -- we are done. Otherwise we repeat the processing with Assume_Valid
10971 -- set to True to generate additional warnings. We can skip that step
10972 -- if Constant_Condition_Warnings is False.
10974 for AV in False .. True loop
10976 Typ : constant Entity_Id := Etype (N);
10977 Op1 : constant Node_Id := Left_Opnd (N);
10978 Op2 : constant Node_Id := Right_Opnd (N);
10980 Res : constant Compare_Result :=
10981 Compile_Time_Compare (Op1, Op2, Assume_Valid => AV);
10982 -- Res indicates if compare outcome can be compile time determined
10984 True_Result : Boolean;
10985 False_Result : Boolean;
10988 case N_Op_Compare (Nkind (N)) is
10990 True_Result := Res = EQ;
10991 False_Result := Res = LT or else Res = GT or else Res = NE;
10994 True_Result := Res in Compare_GE;
10995 False_Result := Res = LT;
10998 and then Constant_Condition_Warnings
10999 and then Comes_From_Source (Original_Node (N))
11000 and then Nkind (Original_Node (N)) = N_Op_Ge
11001 and then not In_Instance
11002 and then Is_Integer_Type (Etype (Left_Opnd (N)))
11003 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
11006 ("can never be greater than, could replace by ""'=""?", N);
11007 Warning_Generated := True;
11011 True_Result := Res = GT;
11012 False_Result := Res in Compare_LE;
11015 True_Result := Res = LT;
11016 False_Result := Res in Compare_GE;
11019 True_Result := Res in Compare_LE;
11020 False_Result := Res = GT;
11023 and then Constant_Condition_Warnings
11024 and then Comes_From_Source (Original_Node (N))
11025 and then Nkind (Original_Node (N)) = N_Op_Le
11026 and then not In_Instance
11027 and then Is_Integer_Type (Etype (Left_Opnd (N)))
11028 and then not Has_Warnings_Off (Etype (Left_Opnd (N)))
11031 ("can never be less than, could replace by ""'=""?", N);
11032 Warning_Generated := True;
11036 True_Result := Res = NE or else Res = GT or else Res = LT;
11037 False_Result := Res = EQ;
11040 -- If this is the first iteration, then we actually convert the
11041 -- comparison into True or False, if the result is certain.
11044 if True_Result or False_Result then
11045 if True_Result then
11046 Result := Standard_True;
11048 Result := Standard_False;
11053 New_Occurrence_Of (Result, Sloc (N))));
11054 Analyze_And_Resolve (N, Typ);
11055 Warn_On_Known_Condition (N);
11059 -- If this is the second iteration (AV = True), and the original
11060 -- node comes from source and we are not in an instance, then give
11061 -- a warning if we know result would be True or False. Note: we
11062 -- know Constant_Condition_Warnings is set if we get here.
11064 elsif Comes_From_Source (Original_Node (N))
11065 and then not In_Instance
11067 if True_Result then
11069 ("condition can only be False if invalid values present?",
11071 elsif False_Result then
11073 ("condition can only be True if invalid values present?",
11079 -- Skip second iteration if not warning on constant conditions or
11080 -- if the first iteration already generated a warning of some kind or
11081 -- if we are in any case assuming all values are valid (so that the
11082 -- first iteration took care of the valid case).
11084 exit when not Constant_Condition_Warnings;
11085 exit when Warning_Generated;
11086 exit when Assume_No_Invalid_Values;
11088 end Rewrite_Comparison;
11090 ----------------------------
11091 -- Safe_In_Place_Array_Op --
11092 ----------------------------
11094 function Safe_In_Place_Array_Op
11097 Op2 : Node_Id) return Boolean
11099 Target : Entity_Id;
11101 function Is_Safe_Operand (Op : Node_Id) return Boolean;
11102 -- Operand is safe if it cannot overlap part of the target of the
11103 -- operation. If the operand and the target are identical, the operand
11104 -- is safe. The operand can be empty in the case of negation.
11106 function Is_Unaliased (N : Node_Id) return Boolean;
11107 -- Check that N is a stand-alone entity
11113 function Is_Unaliased (N : Node_Id) return Boolean is
11117 and then No (Address_Clause (Entity (N)))
11118 and then No (Renamed_Object (Entity (N)));
11121 ---------------------
11122 -- Is_Safe_Operand --
11123 ---------------------
11125 function Is_Safe_Operand (Op : Node_Id) return Boolean is
11130 elsif Is_Entity_Name (Op) then
11131 return Is_Unaliased (Op);
11133 elsif Nkind_In (Op, N_Indexed_Component, N_Selected_Component) then
11134 return Is_Unaliased (Prefix (Op));
11136 elsif Nkind (Op) = N_Slice then
11138 Is_Unaliased (Prefix (Op))
11139 and then Entity (Prefix (Op)) /= Target;
11141 elsif Nkind (Op) = N_Op_Not then
11142 return Is_Safe_Operand (Right_Opnd (Op));
11147 end Is_Safe_Operand;
11149 -- Start of processing for Is_Safe_In_Place_Array_Op
11152 -- Skip this processing if the component size is different from system
11153 -- storage unit (since at least for NOT this would cause problems).
11155 if Component_Size (Etype (Lhs)) /= System_Storage_Unit then
11158 -- Cannot do in place stuff on VM_Target since cannot pass addresses
11160 elsif VM_Target /= No_VM then
11163 -- Cannot do in place stuff if non-standard Boolean representation
11165 elsif Has_Non_Standard_Rep (Component_Type (Etype (Lhs))) then
11168 elsif not Is_Unaliased (Lhs) then
11172 Target := Entity (Lhs);
11173 return Is_Safe_Operand (Op1) and then Is_Safe_Operand (Op2);
11175 end Safe_In_Place_Array_Op;
11177 -----------------------
11178 -- Tagged_Membership --
11179 -----------------------
11181 -- There are two different cases to consider depending on whether the right
11182 -- operand is a class-wide type or not. If not we just compare the actual
11183 -- tag of the left expr to the target type tag:
11185 -- Left_Expr.Tag = Right_Type'Tag;
11187 -- If it is a class-wide type we use the RT function CW_Membership which is
11188 -- usually implemented by looking in the ancestor tables contained in the
11189 -- dispatch table pointed by Left_Expr.Tag for Typ'Tag
11191 -- Ada 2005 (AI-251): If it is a class-wide interface type we use the RT
11192 -- function IW_Membership which is usually implemented by looking in the
11193 -- table of abstract interface types plus the ancestor table contained in
11194 -- the dispatch table pointed by Left_Expr.Tag for Typ'Tag
11196 procedure Tagged_Membership
11198 SCIL_Node : out Node_Id;
11199 Result : out Node_Id)
11201 Left : constant Node_Id := Left_Opnd (N);
11202 Right : constant Node_Id := Right_Opnd (N);
11203 Loc : constant Source_Ptr := Sloc (N);
11205 Full_R_Typ : Entity_Id;
11206 Left_Type : Entity_Id;
11207 New_Node : Node_Id;
11208 Right_Type : Entity_Id;
11212 SCIL_Node := Empty;
11214 -- Handle entities from the limited view
11216 Left_Type := Available_View (Etype (Left));
11217 Right_Type := Available_View (Etype (Right));
11219 -- In the case where the type is an access type, the test is applied
11220 -- using the designated types (needed in Ada 2012 for implicit anonymous
11221 -- access conversions, for AI05-0149).
11223 if Is_Access_Type (Right_Type) then
11224 Left_Type := Designated_Type (Left_Type);
11225 Right_Type := Designated_Type (Right_Type);
11228 if Is_Class_Wide_Type (Left_Type) then
11229 Left_Type := Root_Type (Left_Type);
11232 if Is_Class_Wide_Type (Right_Type) then
11233 Full_R_Typ := Underlying_Type (Root_Type (Right_Type));
11235 Full_R_Typ := Underlying_Type (Right_Type);
11239 Make_Selected_Component (Loc,
11240 Prefix => Relocate_Node (Left),
11242 New_Reference_To (First_Tag_Component (Left_Type), Loc));
11244 if Is_Class_Wide_Type (Right_Type) then
11246 -- No need to issue a run-time check if we statically know that the
11247 -- result of this membership test is always true. For example,
11248 -- considering the following declarations:
11250 -- type Iface is interface;
11251 -- type T is tagged null record;
11252 -- type DT is new T and Iface with null record;
11257 -- These membership tests are always true:
11260 -- Obj2 in T'Class;
11261 -- Obj2 in Iface'Class;
11263 -- We do not need to handle cases where the membership is illegal.
11266 -- Obj1 in DT'Class; -- Compile time error
11267 -- Obj1 in Iface'Class; -- Compile time error
11269 if not Is_Class_Wide_Type (Left_Type)
11270 and then (Is_Ancestor (Etype (Right_Type), Left_Type,
11271 Use_Full_View => True)
11272 or else (Is_Interface (Etype (Right_Type))
11273 and then Interface_Present_In_Ancestor
11275 Iface => Etype (Right_Type))))
11277 Result := New_Reference_To (Standard_True, Loc);
11281 -- Ada 2005 (AI-251): Class-wide applied to interfaces
11283 if Is_Interface (Etype (Class_Wide_Type (Right_Type)))
11285 -- Support to: "Iface_CW_Typ in Typ'Class"
11287 or else Is_Interface (Left_Type)
11289 -- Issue error if IW_Membership operation not available in a
11290 -- configurable run time setting.
11292 if not RTE_Available (RE_IW_Membership) then
11294 ("dynamic membership test on interface types", N);
11300 Make_Function_Call (Loc,
11301 Name => New_Occurrence_Of (RTE (RE_IW_Membership), Loc),
11302 Parameter_Associations => New_List (
11303 Make_Attribute_Reference (Loc,
11305 Attribute_Name => Name_Address),
11307 Node (First_Elmt (Access_Disp_Table (Full_R_Typ))),
11310 -- Ada 95: Normal case
11313 Build_CW_Membership (Loc,
11314 Obj_Tag_Node => Obj_Tag,
11317 Node (First_Elmt (Access_Disp_Table (Full_R_Typ))), Loc),
11319 New_Node => New_Node);
11321 -- Generate the SCIL node for this class-wide membership test.
11322 -- Done here because the previous call to Build_CW_Membership
11323 -- relocates Obj_Tag.
11325 if Generate_SCIL then
11326 SCIL_Node := Make_SCIL_Membership_Test (Sloc (N));
11327 Set_SCIL_Entity (SCIL_Node, Etype (Right_Type));
11328 Set_SCIL_Tag_Value (SCIL_Node, Obj_Tag);
11331 Result := New_Node;
11334 -- Right_Type is not a class-wide type
11337 -- No need to check the tag of the object if Right_Typ is abstract
11339 if Is_Abstract_Type (Right_Type) then
11340 Result := New_Reference_To (Standard_False, Loc);
11345 Left_Opnd => Obj_Tag,
11348 (Node (First_Elmt (Access_Disp_Table (Full_R_Typ))), Loc));
11351 end Tagged_Membership;
11353 ------------------------------
11354 -- Unary_Op_Validity_Checks --
11355 ------------------------------
11357 procedure Unary_Op_Validity_Checks (N : Node_Id) is
11359 if Validity_Checks_On and Validity_Check_Operands then
11360 Ensure_Valid (Right_Opnd (N));
11362 end Unary_Op_Validity_Checks;