1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2009, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Aggr; use Exp_Aggr;
33 with Exp_Ch6; use Exp_Ch6;
34 with Exp_Ch7; use Exp_Ch7;
35 with Inline; use Inline;
36 with Itypes; use Itypes;
38 with Nlists; use Nlists;
39 with Nmake; use Nmake;
41 with Restrict; use Restrict;
42 with Rident; use Rident;
44 with Sem_Aux; use Sem_Aux;
45 with Sem_Ch8; use Sem_Ch8;
46 with Sem_Eval; use Sem_Eval;
47 with Sem_Res; use Sem_Res;
48 with Sem_Type; use Sem_Type;
49 with Sem_Util; use Sem_Util;
50 with Snames; use Snames;
51 with Stand; use Stand;
52 with Stringt; use Stringt;
53 with Targparm; use Targparm;
54 with Tbuild; use Tbuild;
55 with Ttypes; use Ttypes;
56 with Uintp; use Uintp;
57 with Urealp; use Urealp;
58 with Validsw; use Validsw;
60 package body Exp_Util is
62 -----------------------
63 -- Local Subprograms --
64 -----------------------
66 function Build_Task_Array_Image
70 Dyn : Boolean := False) return Node_Id;
71 -- Build function to generate the image string for a task that is an
72 -- array component, concatenating the images of each index. To avoid
73 -- storage leaks, the string is built with successive slice assignments.
74 -- The flag Dyn indicates whether this is called for the initialization
75 -- procedure of an array of tasks, or for the name of a dynamically
76 -- created task that is assigned to an indexed component.
78 function Build_Task_Image_Function
82 Res : Entity_Id) return Node_Id;
83 -- Common processing for Task_Array_Image and Task_Record_Image.
84 -- Build function body that computes image.
86 procedure Build_Task_Image_Prefix
95 -- Common processing for Task_Array_Image and Task_Record_Image.
96 -- Create local variables and assign prefix of name to result string.
98 function Build_Task_Record_Image
101 Dyn : Boolean := False) return Node_Id;
102 -- Build function to generate the image string for a task that is a
103 -- record component. Concatenate name of variable with that of selector.
104 -- The flag Dyn indicates whether this is called for the initialization
105 -- procedure of record with task components, or for a dynamically
106 -- created task that is assigned to a selected component.
108 function Make_CW_Equivalent_Type
110 E : Node_Id) return Entity_Id;
111 -- T is a class-wide type entity, E is the initial expression node that
112 -- constrains T in case such as: " X: T := E" or "new T'(E)"
113 -- This function returns the entity of the Equivalent type and inserts
114 -- on the fly the necessary declaration such as:
116 -- type anon is record
117 -- _parent : Root_Type (T); constrained with E discriminants (if any)
118 -- Extension : String (1 .. expr to match size of E);
121 -- This record is compatible with any object of the class of T thanks
122 -- to the first field and has the same size as E thanks to the second.
124 function Make_Literal_Range
126 Literal_Typ : Entity_Id) return Node_Id;
127 -- Produce a Range node whose bounds are:
128 -- Low_Bound (Literal_Type) ..
129 -- Low_Bound (Literal_Type) + (Length (Literal_Typ) - 1)
130 -- this is used for expanding declarations like X : String := "sdfgdfg";
132 -- If the index type of the target array is not integer, we generate:
133 -- Low_Bound (Literal_Type) ..
135 -- (Literal_Type'Pos (Low_Bound (Literal_Type))
136 -- + (Length (Literal_Typ) -1))
138 function Make_Non_Empty_Check
140 N : Node_Id) return Node_Id;
141 -- Produce a boolean expression checking that the unidimensional array
142 -- node N is not empty.
144 function New_Class_Wide_Subtype
146 N : Node_Id) return Entity_Id;
147 -- Create an implicit subtype of CW_Typ attached to node N
149 ----------------------
150 -- Adjust_Condition --
151 ----------------------
153 procedure Adjust_Condition (N : Node_Id) is
160 Loc : constant Source_Ptr := Sloc (N);
161 T : constant Entity_Id := Etype (N);
165 -- For now, we simply ignore a call where the argument has no
166 -- type (probably case of unanalyzed condition), or has a type
167 -- that is not Boolean. This is because this is a pretty marginal
168 -- piece of functionality, and violations of these rules are
169 -- likely to be truly marginal (how much code uses Fortran Logical
170 -- as the barrier to a protected entry?) and we do not want to
171 -- blow up existing programs. We can change this to an assertion
172 -- after 3.12a is released ???
174 if No (T) or else not Is_Boolean_Type (T) then
178 -- Apply validity checking if needed
180 if Validity_Checks_On and Validity_Check_Tests then
184 -- Immediate return if standard boolean, the most common case,
185 -- where nothing needs to be done.
187 if Base_Type (T) = Standard_Boolean then
191 -- Case of zero/non-zero semantics or non-standard enumeration
192 -- representation. In each case, we rewrite the node as:
194 -- ityp!(N) /= False'Enum_Rep
196 -- where ityp is an integer type with large enough size to hold
197 -- any value of type T.
199 if Nonzero_Is_True (T) or else Has_Non_Standard_Rep (T) then
200 if Esize (T) <= Esize (Standard_Integer) then
201 Ti := Standard_Integer;
203 Ti := Standard_Long_Long_Integer;
208 Left_Opnd => Unchecked_Convert_To (Ti, N),
210 Make_Attribute_Reference (Loc,
211 Attribute_Name => Name_Enum_Rep,
213 New_Occurrence_Of (First_Literal (T), Loc))));
214 Analyze_And_Resolve (N, Standard_Boolean);
217 Rewrite (N, Convert_To (Standard_Boolean, N));
218 Analyze_And_Resolve (N, Standard_Boolean);
221 end Adjust_Condition;
223 ------------------------
224 -- Adjust_Result_Type --
225 ------------------------
227 procedure Adjust_Result_Type (N : Node_Id; T : Entity_Id) is
229 -- Ignore call if current type is not Standard.Boolean
231 if Etype (N) /= Standard_Boolean then
235 -- If result is already of correct type, nothing to do. Note that
236 -- this will get the most common case where everything has a type
237 -- of Standard.Boolean.
239 if Base_Type (T) = Standard_Boolean then
244 KP : constant Node_Kind := Nkind (Parent (N));
247 -- If result is to be used as a Condition in the syntax, no need
248 -- to convert it back, since if it was changed to Standard.Boolean
249 -- using Adjust_Condition, that is just fine for this usage.
251 if KP in N_Raise_xxx_Error or else KP in N_Has_Condition then
254 -- If result is an operand of another logical operation, no need
255 -- to reset its type, since Standard.Boolean is just fine, and
256 -- such operations always do Adjust_Condition on their operands.
258 elsif KP in N_Op_Boolean
259 or else KP in N_Short_Circuit
260 or else KP = N_Op_Not
264 -- Otherwise we perform a conversion from the current type,
265 -- which must be Standard.Boolean, to the desired type.
269 Rewrite (N, Convert_To (T, N));
270 Analyze_And_Resolve (N, T);
274 end Adjust_Result_Type;
276 --------------------------
277 -- Append_Freeze_Action --
278 --------------------------
280 procedure Append_Freeze_Action (T : Entity_Id; N : Node_Id) is
284 Ensure_Freeze_Node (T);
285 Fnode := Freeze_Node (T);
287 if No (Actions (Fnode)) then
288 Set_Actions (Fnode, New_List);
291 Append (N, Actions (Fnode));
292 end Append_Freeze_Action;
294 ---------------------------
295 -- Append_Freeze_Actions --
296 ---------------------------
298 procedure Append_Freeze_Actions (T : Entity_Id; L : List_Id) is
299 Fnode : constant Node_Id := Freeze_Node (T);
306 if No (Actions (Fnode)) then
307 Set_Actions (Fnode, L);
310 Append_List (L, Actions (Fnode));
314 end Append_Freeze_Actions;
316 ------------------------
317 -- Build_Runtime_Call --
318 ------------------------
320 function Build_Runtime_Call (Loc : Source_Ptr; RE : RE_Id) return Node_Id is
322 -- If entity is not available, we can skip making the call (this avoids
323 -- junk duplicated error messages in a number of cases).
325 if not RTE_Available (RE) then
326 return Make_Null_Statement (Loc);
329 Make_Procedure_Call_Statement (Loc,
330 Name => New_Reference_To (RTE (RE), Loc));
332 end Build_Runtime_Call;
334 ----------------------------
335 -- Build_Task_Array_Image --
336 ----------------------------
338 -- This function generates the body for a function that constructs the
339 -- image string for a task that is an array component. The function is
340 -- local to the init proc for the array type, and is called for each one
341 -- of the components. The constructed image has the form of an indexed
342 -- component, whose prefix is the outer variable of the array type.
343 -- The n-dimensional array type has known indices Index, Index2...
344 -- Id_Ref is an indexed component form created by the enclosing init proc.
345 -- Its successive indices are Val1, Val2, ... which are the loop variables
346 -- in the loops that call the individual task init proc on each component.
348 -- The generated function has the following structure:
350 -- function F return String is
351 -- Pref : string renames Task_Name;
352 -- T1 : String := Index1'Image (Val1);
354 -- Tn : String := indexn'image (Valn);
355 -- Len : Integer := T1'Length + ... + Tn'Length + n + 1;
356 -- -- Len includes commas and the end parentheses.
357 -- Res : String (1..Len);
358 -- Pos : Integer := Pref'Length;
361 -- Res (1 .. Pos) := Pref;
365 -- Res (Pos .. Pos + T1'Length - 1) := T1;
366 -- Pos := Pos + T1'Length;
370 -- Res (Pos .. Pos + Tn'Length - 1) := Tn;
376 -- Needless to say, multidimensional arrays of tasks are rare enough
377 -- that the bulkiness of this code is not really a concern.
379 function Build_Task_Array_Image
383 Dyn : Boolean := False) return Node_Id
385 Dims : constant Nat := Number_Dimensions (A_Type);
386 -- Number of dimensions for array of tasks
388 Temps : array (1 .. Dims) of Entity_Id;
389 -- Array of temporaries to hold string for each index
395 -- Total length of generated name
398 -- Running index for substring assignments
401 -- Name of enclosing variable, prefix of resulting name
404 -- String to hold result
407 -- Value of successive indices
410 -- Expression to compute total size of string
413 -- Entity for name at one index position
415 Decls : constant List_Id := New_List;
416 Stats : constant List_Id := New_List;
419 Pref := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
421 -- For a dynamic task, the name comes from the target variable.
422 -- For a static one it is a formal of the enclosing init proc.
425 Get_Name_String (Chars (Entity (Prefix (Id_Ref))));
427 Make_Object_Declaration (Loc,
428 Defining_Identifier => Pref,
429 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
431 Make_String_Literal (Loc,
432 Strval => String_From_Name_Buffer)));
436 Make_Object_Renaming_Declaration (Loc,
437 Defining_Identifier => Pref,
438 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
439 Name => Make_Identifier (Loc, Name_uTask_Name)));
442 Indx := First_Index (A_Type);
443 Val := First (Expressions (Id_Ref));
445 for J in 1 .. Dims loop
446 T := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
450 Make_Object_Declaration (Loc,
451 Defining_Identifier => T,
452 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
454 Make_Attribute_Reference (Loc,
455 Attribute_Name => Name_Image,
457 New_Occurrence_Of (Etype (Indx), Loc),
458 Expressions => New_List (
459 New_Copy_Tree (Val)))));
465 Sum := Make_Integer_Literal (Loc, Dims + 1);
471 Make_Attribute_Reference (Loc,
472 Attribute_Name => Name_Length,
474 New_Occurrence_Of (Pref, Loc),
475 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
477 for J in 1 .. Dims loop
482 Make_Attribute_Reference (Loc,
483 Attribute_Name => Name_Length,
485 New_Occurrence_Of (Temps (J), Loc),
486 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
489 Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats);
491 Set_Character_Literal_Name (Char_Code (Character'Pos ('(')));
494 Make_Assignment_Statement (Loc,
495 Name => Make_Indexed_Component (Loc,
496 Prefix => New_Occurrence_Of (Res, Loc),
497 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
499 Make_Character_Literal (Loc,
501 Char_Literal_Value =>
502 UI_From_Int (Character'Pos ('(')))));
505 Make_Assignment_Statement (Loc,
506 Name => New_Occurrence_Of (Pos, Loc),
509 Left_Opnd => New_Occurrence_Of (Pos, Loc),
510 Right_Opnd => Make_Integer_Literal (Loc, 1))));
512 for J in 1 .. Dims loop
515 Make_Assignment_Statement (Loc,
516 Name => Make_Slice (Loc,
517 Prefix => New_Occurrence_Of (Res, Loc),
520 Low_Bound => New_Occurrence_Of (Pos, Loc),
521 High_Bound => Make_Op_Subtract (Loc,
524 Left_Opnd => New_Occurrence_Of (Pos, Loc),
526 Make_Attribute_Reference (Loc,
527 Attribute_Name => Name_Length,
529 New_Occurrence_Of (Temps (J), Loc),
531 New_List (Make_Integer_Literal (Loc, 1)))),
532 Right_Opnd => Make_Integer_Literal (Loc, 1)))),
534 Expression => New_Occurrence_Of (Temps (J), Loc)));
538 Make_Assignment_Statement (Loc,
539 Name => New_Occurrence_Of (Pos, Loc),
542 Left_Opnd => New_Occurrence_Of (Pos, Loc),
544 Make_Attribute_Reference (Loc,
545 Attribute_Name => Name_Length,
546 Prefix => New_Occurrence_Of (Temps (J), Loc),
548 New_List (Make_Integer_Literal (Loc, 1))))));
550 Set_Character_Literal_Name (Char_Code (Character'Pos (',')));
553 Make_Assignment_Statement (Loc,
554 Name => Make_Indexed_Component (Loc,
555 Prefix => New_Occurrence_Of (Res, Loc),
556 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
558 Make_Character_Literal (Loc,
560 Char_Literal_Value =>
561 UI_From_Int (Character'Pos (',')))));
564 Make_Assignment_Statement (Loc,
565 Name => New_Occurrence_Of (Pos, Loc),
568 Left_Opnd => New_Occurrence_Of (Pos, Loc),
569 Right_Opnd => Make_Integer_Literal (Loc, 1))));
573 Set_Character_Literal_Name (Char_Code (Character'Pos (')')));
576 Make_Assignment_Statement (Loc,
577 Name => Make_Indexed_Component (Loc,
578 Prefix => New_Occurrence_Of (Res, Loc),
579 Expressions => New_List (New_Occurrence_Of (Len, Loc))),
581 Make_Character_Literal (Loc,
583 Char_Literal_Value =>
584 UI_From_Int (Character'Pos (')')))));
585 return Build_Task_Image_Function (Loc, Decls, Stats, Res);
586 end Build_Task_Array_Image;
588 ----------------------------
589 -- Build_Task_Image_Decls --
590 ----------------------------
592 function Build_Task_Image_Decls
596 In_Init_Proc : Boolean := False) return List_Id
598 Decls : constant List_Id := New_List;
599 T_Id : Entity_Id := Empty;
601 Expr : Node_Id := Empty;
602 Fun : Node_Id := Empty;
603 Is_Dyn : constant Boolean :=
604 Nkind (Parent (Id_Ref)) = N_Assignment_Statement
606 Nkind (Expression (Parent (Id_Ref))) = N_Allocator;
609 -- If Discard_Names or No_Implicit_Heap_Allocations are in effect,
610 -- generate a dummy declaration only.
612 if Restriction_Active (No_Implicit_Heap_Allocations)
613 or else Global_Discard_Names
615 T_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
620 Make_Object_Declaration (Loc,
621 Defining_Identifier => T_Id,
622 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
624 Make_String_Literal (Loc,
625 Strval => String_From_Name_Buffer)));
628 if Nkind (Id_Ref) = N_Identifier
629 or else Nkind (Id_Ref) = N_Defining_Identifier
631 -- For a simple variable, the image of the task is built from
632 -- the name of the variable. To avoid possible conflict with
633 -- the anonymous type created for a single protected object,
634 -- add a numeric suffix.
637 Make_Defining_Identifier (Loc,
638 New_External_Name (Chars (Id_Ref), 'T', 1));
640 Get_Name_String (Chars (Id_Ref));
643 Make_String_Literal (Loc,
644 Strval => String_From_Name_Buffer);
646 elsif Nkind (Id_Ref) = N_Selected_Component then
648 Make_Defining_Identifier (Loc,
649 New_External_Name (Chars (Selector_Name (Id_Ref)), 'T'));
650 Fun := Build_Task_Record_Image (Loc, Id_Ref, Is_Dyn);
652 elsif Nkind (Id_Ref) = N_Indexed_Component then
654 Make_Defining_Identifier (Loc,
655 New_External_Name (Chars (A_Type), 'N'));
657 Fun := Build_Task_Array_Image (Loc, Id_Ref, A_Type, Is_Dyn);
661 if Present (Fun) then
663 Expr := Make_Function_Call (Loc,
664 Name => New_Occurrence_Of (Defining_Entity (Fun), Loc));
666 if not In_Init_Proc and then VM_Target = No_VM then
667 Set_Uses_Sec_Stack (Defining_Entity (Fun));
671 Decl := Make_Object_Declaration (Loc,
672 Defining_Identifier => T_Id,
673 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
674 Constant_Present => True,
677 Append (Decl, Decls);
679 end Build_Task_Image_Decls;
681 -------------------------------
682 -- Build_Task_Image_Function --
683 -------------------------------
685 function Build_Task_Image_Function
689 Res : Entity_Id) return Node_Id
695 Make_Simple_Return_Statement (Loc,
696 Expression => New_Occurrence_Of (Res, Loc)));
698 Spec := Make_Function_Specification (Loc,
699 Defining_Unit_Name =>
700 Make_Defining_Identifier (Loc, New_Internal_Name ('F')),
701 Result_Definition => New_Occurrence_Of (Standard_String, Loc));
703 -- Calls to 'Image use the secondary stack, which must be cleaned
704 -- up after the task name is built.
706 return Make_Subprogram_Body (Loc,
707 Specification => Spec,
708 Declarations => Decls,
709 Handled_Statement_Sequence =>
710 Make_Handled_Sequence_Of_Statements (Loc, Statements => Stats));
711 end Build_Task_Image_Function;
713 -----------------------------
714 -- Build_Task_Image_Prefix --
715 -----------------------------
717 procedure Build_Task_Image_Prefix
728 Len := Make_Defining_Identifier (Loc, New_Internal_Name ('L'));
731 Make_Object_Declaration (Loc,
732 Defining_Identifier => Len,
733 Object_Definition => New_Occurrence_Of (Standard_Integer, Loc),
736 Res := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
739 Make_Object_Declaration (Loc,
740 Defining_Identifier => Res,
742 Make_Subtype_Indication (Loc,
743 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
745 Make_Index_Or_Discriminant_Constraint (Loc,
749 Low_Bound => Make_Integer_Literal (Loc, 1),
750 High_Bound => New_Occurrence_Of (Len, Loc)))))));
752 Pos := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
755 Make_Object_Declaration (Loc,
756 Defining_Identifier => Pos,
757 Object_Definition => New_Occurrence_Of (Standard_Integer, Loc)));
759 -- Pos := Prefix'Length;
762 Make_Assignment_Statement (Loc,
763 Name => New_Occurrence_Of (Pos, Loc),
765 Make_Attribute_Reference (Loc,
766 Attribute_Name => Name_Length,
767 Prefix => New_Occurrence_Of (Prefix, Loc),
769 New_List (Make_Integer_Literal (Loc, 1)))));
771 -- Res (1 .. Pos) := Prefix;
774 Make_Assignment_Statement (Loc,
775 Name => Make_Slice (Loc,
776 Prefix => New_Occurrence_Of (Res, Loc),
779 Low_Bound => Make_Integer_Literal (Loc, 1),
780 High_Bound => New_Occurrence_Of (Pos, Loc))),
782 Expression => New_Occurrence_Of (Prefix, Loc)));
785 Make_Assignment_Statement (Loc,
786 Name => New_Occurrence_Of (Pos, Loc),
789 Left_Opnd => New_Occurrence_Of (Pos, Loc),
790 Right_Opnd => Make_Integer_Literal (Loc, 1))));
791 end Build_Task_Image_Prefix;
793 -----------------------------
794 -- Build_Task_Record_Image --
795 -----------------------------
797 function Build_Task_Record_Image
800 Dyn : Boolean := False) return Node_Id
803 -- Total length of generated name
809 -- String to hold result
812 -- Name of enclosing variable, prefix of resulting name
815 -- Expression to compute total size of string
818 -- Entity for selector name
820 Decls : constant List_Id := New_List;
821 Stats : constant List_Id := New_List;
824 Pref := Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
826 -- For a dynamic task, the name comes from the target variable.
827 -- For a static one it is a formal of the enclosing init proc.
830 Get_Name_String (Chars (Entity (Prefix (Id_Ref))));
832 Make_Object_Declaration (Loc,
833 Defining_Identifier => Pref,
834 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
836 Make_String_Literal (Loc,
837 Strval => String_From_Name_Buffer)));
841 Make_Object_Renaming_Declaration (Loc,
842 Defining_Identifier => Pref,
843 Subtype_Mark => New_Occurrence_Of (Standard_String, Loc),
844 Name => Make_Identifier (Loc, Name_uTask_Name)));
847 Sel := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
849 Get_Name_String (Chars (Selector_Name (Id_Ref)));
852 Make_Object_Declaration (Loc,
853 Defining_Identifier => Sel,
854 Object_Definition => New_Occurrence_Of (Standard_String, Loc),
856 Make_String_Literal (Loc,
857 Strval => String_From_Name_Buffer)));
859 Sum := Make_Integer_Literal (Loc, Nat (Name_Len + 1));
865 Make_Attribute_Reference (Loc,
866 Attribute_Name => Name_Length,
868 New_Occurrence_Of (Pref, Loc),
869 Expressions => New_List (Make_Integer_Literal (Loc, 1))));
871 Build_Task_Image_Prefix (Loc, Len, Res, Pos, Pref, Sum, Decls, Stats);
873 Set_Character_Literal_Name (Char_Code (Character'Pos ('.')));
878 Make_Assignment_Statement (Loc,
879 Name => Make_Indexed_Component (Loc,
880 Prefix => New_Occurrence_Of (Res, Loc),
881 Expressions => New_List (New_Occurrence_Of (Pos, Loc))),
883 Make_Character_Literal (Loc,
885 Char_Literal_Value =>
886 UI_From_Int (Character'Pos ('.')))));
889 Make_Assignment_Statement (Loc,
890 Name => New_Occurrence_Of (Pos, Loc),
893 Left_Opnd => New_Occurrence_Of (Pos, Loc),
894 Right_Opnd => Make_Integer_Literal (Loc, 1))));
896 -- Res (Pos .. Len) := Selector;
899 Make_Assignment_Statement (Loc,
900 Name => Make_Slice (Loc,
901 Prefix => New_Occurrence_Of (Res, Loc),
904 Low_Bound => New_Occurrence_Of (Pos, Loc),
905 High_Bound => New_Occurrence_Of (Len, Loc))),
906 Expression => New_Occurrence_Of (Sel, Loc)));
908 return Build_Task_Image_Function (Loc, Decls, Stats, Res);
909 end Build_Task_Record_Image;
911 ----------------------------------
912 -- Component_May_Be_Bit_Aligned --
913 ----------------------------------
915 function Component_May_Be_Bit_Aligned (Comp : Entity_Id) return Boolean is
917 -- If no component clause, then everything is fine, since the back end
918 -- never bit-misaligns by default, even if there is a pragma Packed for
921 if No (Component_Clause (Comp)) then
925 -- It is only array and record types that cause trouble
927 if not Is_Record_Type (Etype (Comp))
928 and then not Is_Array_Type (Etype (Comp))
932 -- If we know that we have a small (64 bits or less) record
933 -- or bit-packed array, then everything is fine, since the
934 -- back end can handle these cases correctly.
936 elsif Esize (Comp) <= 64
937 and then (Is_Record_Type (Etype (Comp))
938 or else Is_Bit_Packed_Array (Etype (Comp)))
942 -- Otherwise if the component is not byte aligned, we know we have the
943 -- nasty unaligned case.
945 elsif Normalized_First_Bit (Comp) /= Uint_0
946 or else Esize (Comp) mod System_Storage_Unit /= Uint_0
950 -- If we are large and byte aligned, then OK at this level
955 end Component_May_Be_Bit_Aligned;
957 -----------------------------------
958 -- Corresponding_Runtime_Package --
959 -----------------------------------
961 function Corresponding_Runtime_Package (Typ : Entity_Id) return RTU_Id is
962 Pkg_Id : RTU_Id := RTU_Null;
965 pragma Assert (Is_Concurrent_Type (Typ));
967 if Ekind (Typ) in Protected_Kind then
969 or else Has_Interrupt_Handler (Typ)
970 or else (Has_Attach_Handler (Typ)
971 and then not Restricted_Profile)
973 -- A protected type without entries that covers an interface and
974 -- overrides the abstract routines with protected procedures is
975 -- considered equivalent to a protected type with entries in the
976 -- context of dispatching select statements. It is sufficient to
977 -- check for the presence of an interface list in the declaration
978 -- node to recognize this case.
980 or else Present (Interface_List (Parent (Typ)))
983 or else Restriction_Active (No_Entry_Queue) = False
984 or else Number_Entries (Typ) > 1
985 or else (Has_Attach_Handler (Typ)
986 and then not Restricted_Profile)
988 Pkg_Id := System_Tasking_Protected_Objects_Entries;
990 Pkg_Id := System_Tasking_Protected_Objects_Single_Entry;
994 Pkg_Id := System_Tasking_Protected_Objects;
999 end Corresponding_Runtime_Package;
1001 -------------------------------
1002 -- Convert_To_Actual_Subtype --
1003 -------------------------------
1005 procedure Convert_To_Actual_Subtype (Exp : Entity_Id) is
1009 Act_ST := Get_Actual_Subtype (Exp);
1011 if Act_ST = Etype (Exp) then
1016 Convert_To (Act_ST, Relocate_Node (Exp)));
1017 Analyze_And_Resolve (Exp, Act_ST);
1019 end Convert_To_Actual_Subtype;
1021 -----------------------------------
1022 -- Current_Sem_Unit_Declarations --
1023 -----------------------------------
1025 function Current_Sem_Unit_Declarations return List_Id is
1026 U : Node_Id := Unit (Cunit (Current_Sem_Unit));
1030 -- If the current unit is a package body, locate the visible
1031 -- declarations of the package spec.
1033 if Nkind (U) = N_Package_Body then
1034 U := Unit (Library_Unit (Cunit (Current_Sem_Unit)));
1037 if Nkind (U) = N_Package_Declaration then
1038 U := Specification (U);
1039 Decls := Visible_Declarations (U);
1043 Set_Visible_Declarations (U, Decls);
1047 Decls := Declarations (U);
1051 Set_Declarations (U, Decls);
1056 end Current_Sem_Unit_Declarations;
1058 -----------------------
1059 -- Duplicate_Subexpr --
1060 -----------------------
1062 function Duplicate_Subexpr
1064 Name_Req : Boolean := False) return Node_Id
1067 Remove_Side_Effects (Exp, Name_Req);
1068 return New_Copy_Tree (Exp);
1069 end Duplicate_Subexpr;
1071 ---------------------------------
1072 -- Duplicate_Subexpr_No_Checks --
1073 ---------------------------------
1075 function Duplicate_Subexpr_No_Checks
1077 Name_Req : Boolean := False) return Node_Id
1082 Remove_Side_Effects (Exp, Name_Req);
1083 New_Exp := New_Copy_Tree (Exp);
1084 Remove_Checks (New_Exp);
1086 end Duplicate_Subexpr_No_Checks;
1088 -----------------------------------
1089 -- Duplicate_Subexpr_Move_Checks --
1090 -----------------------------------
1092 function Duplicate_Subexpr_Move_Checks
1094 Name_Req : Boolean := False) return Node_Id
1099 Remove_Side_Effects (Exp, Name_Req);
1100 New_Exp := New_Copy_Tree (Exp);
1101 Remove_Checks (Exp);
1103 end Duplicate_Subexpr_Move_Checks;
1105 --------------------
1106 -- Ensure_Defined --
1107 --------------------
1109 procedure Ensure_Defined (Typ : Entity_Id; N : Node_Id) is
1113 -- An itype reference must only be created if this is a local
1114 -- itype, so that gigi can elaborate it on the proper objstack.
1117 and then Scope (Typ) = Current_Scope
1119 IR := Make_Itype_Reference (Sloc (N));
1120 Set_Itype (IR, Typ);
1121 Insert_Action (N, IR);
1125 --------------------
1126 -- Entry_Names_OK --
1127 --------------------
1129 function Entry_Names_OK return Boolean is
1132 not Restricted_Profile
1133 and then not Global_Discard_Names
1134 and then not Restriction_Active (No_Implicit_Heap_Allocations)
1135 and then not Restriction_Active (No_Local_Allocators);
1138 ---------------------
1139 -- Evolve_And_Then --
1140 ---------------------
1142 procedure Evolve_And_Then (Cond : in out Node_Id; Cond1 : Node_Id) is
1148 Make_And_Then (Sloc (Cond1),
1150 Right_Opnd => Cond1);
1152 end Evolve_And_Then;
1154 --------------------
1155 -- Evolve_Or_Else --
1156 --------------------
1158 procedure Evolve_Or_Else (Cond : in out Node_Id; Cond1 : Node_Id) is
1164 Make_Or_Else (Sloc (Cond1),
1166 Right_Opnd => Cond1);
1170 ------------------------------
1171 -- Expand_Subtype_From_Expr --
1172 ------------------------------
1174 -- This function is applicable for both static and dynamic allocation of
1175 -- objects which are constrained by an initial expression. Basically it
1176 -- transforms an unconstrained subtype indication into a constrained one.
1177 -- The expression may also be transformed in certain cases in order to
1178 -- avoid multiple evaluation. In the static allocation case, the general
1183 -- is transformed into
1185 -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr;
1187 -- Here are the main cases :
1189 -- <if Expr is a Slice>
1190 -- Val : T ([Index_Subtype (Expr)]) := Expr;
1192 -- <elsif Expr is a String Literal>
1193 -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr;
1195 -- <elsif Expr is Constrained>
1196 -- subtype T is Type_Of_Expr
1199 -- <elsif Expr is an entity_name>
1200 -- Val : T (constraints taken from Expr) := Expr;
1203 -- type Axxx is access all T;
1204 -- Rval : Axxx := Expr'ref;
1205 -- Val : T (constraints taken from Rval) := Rval.all;
1207 -- ??? note: when the Expression is allocated in the secondary stack
1208 -- we could use it directly instead of copying it by declaring
1209 -- Val : T (...) renames Rval.all
1211 procedure Expand_Subtype_From_Expr
1213 Unc_Type : Entity_Id;
1214 Subtype_Indic : Node_Id;
1217 Loc : constant Source_Ptr := Sloc (N);
1218 Exp_Typ : constant Entity_Id := Etype (Exp);
1222 -- In general we cannot build the subtype if expansion is disabled,
1223 -- because internal entities may not have been defined. However, to
1224 -- avoid some cascaded errors, we try to continue when the expression
1225 -- is an array (or string), because it is safe to compute the bounds.
1226 -- It is in fact required to do so even in a generic context, because
1227 -- there may be constants that depend on bounds of string literal.
1229 if not Expander_Active
1230 and then (No (Etype (Exp))
1231 or else Base_Type (Etype (Exp)) /= Standard_String)
1236 if Nkind (Exp) = N_Slice then
1238 Slice_Type : constant Entity_Id := Etype (First_Index (Exp_Typ));
1241 Rewrite (Subtype_Indic,
1242 Make_Subtype_Indication (Loc,
1243 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1245 Make_Index_Or_Discriminant_Constraint (Loc,
1246 Constraints => New_List
1247 (New_Reference_To (Slice_Type, Loc)))));
1249 -- This subtype indication may be used later for constraint checks
1250 -- we better make sure that if a variable was used as a bound of
1251 -- of the original slice, its value is frozen.
1253 Force_Evaluation (Low_Bound (Scalar_Range (Slice_Type)));
1254 Force_Evaluation (High_Bound (Scalar_Range (Slice_Type)));
1257 elsif Ekind (Exp_Typ) = E_String_Literal_Subtype then
1258 Rewrite (Subtype_Indic,
1259 Make_Subtype_Indication (Loc,
1260 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1262 Make_Index_Or_Discriminant_Constraint (Loc,
1263 Constraints => New_List (
1264 Make_Literal_Range (Loc,
1265 Literal_Typ => Exp_Typ)))));
1267 elsif Is_Constrained (Exp_Typ)
1268 and then not Is_Class_Wide_Type (Unc_Type)
1270 if Is_Itype (Exp_Typ) then
1272 -- Within an initialization procedure, a selected component
1273 -- denotes a component of the enclosing record, and it appears
1274 -- as an actual in a call to its own initialization procedure.
1275 -- If this component depends on the outer discriminant, we must
1276 -- generate the proper actual subtype for it.
1278 if Nkind (Exp) = N_Selected_Component
1279 and then Within_Init_Proc
1282 Decl : constant Node_Id :=
1283 Build_Actual_Subtype_Of_Component (Exp_Typ, Exp);
1285 if Present (Decl) then
1286 Insert_Action (N, Decl);
1287 T := Defining_Identifier (Decl);
1293 -- No need to generate a new one (new what???)
1301 Make_Defining_Identifier (Loc,
1302 Chars => New_Internal_Name ('T'));
1305 Make_Subtype_Declaration (Loc,
1306 Defining_Identifier => T,
1307 Subtype_Indication => New_Reference_To (Exp_Typ, Loc)));
1309 -- This type is marked as an itype even though it has an
1310 -- explicit declaration because otherwise it can be marked
1311 -- with Is_Generic_Actual_Type and generate spurious errors.
1312 -- (see sem_ch8.Analyze_Package_Renaming and sem_type.covers)
1315 Set_Associated_Node_For_Itype (T, Exp);
1318 Rewrite (Subtype_Indic, New_Reference_To (T, Loc));
1320 -- nothing needs to be done for private types with unknown discriminants
1321 -- if the underlying type is not an unconstrained composite type.
1323 elsif Is_Private_Type (Unc_Type)
1324 and then Has_Unknown_Discriminants (Unc_Type)
1325 and then (not Is_Composite_Type (Underlying_Type (Unc_Type))
1326 or else Is_Constrained (Underlying_Type (Unc_Type)))
1330 -- Case of derived type with unknown discriminants where the parent type
1331 -- also has unknown discriminants.
1333 elsif Is_Record_Type (Unc_Type)
1334 and then not Is_Class_Wide_Type (Unc_Type)
1335 and then Has_Unknown_Discriminants (Unc_Type)
1336 and then Has_Unknown_Discriminants (Underlying_Type (Unc_Type))
1338 -- Nothing to be done if no underlying record view available
1340 if No (Underlying_Record_View (Unc_Type)) then
1343 -- Otherwise use the Underlying_Record_View to create the proper
1344 -- constrained subtype for an object of a derived type with unknown
1348 Remove_Side_Effects (Exp);
1349 Rewrite (Subtype_Indic,
1350 Make_Subtype_From_Expr (Exp, Underlying_Record_View (Unc_Type)));
1353 -- In Ada95, Nothing to be done if the type of the expression is
1354 -- limited, because in this case the expression cannot be copied,
1355 -- and its use can only be by reference.
1357 -- In Ada2005, the context can be an object declaration whose expression
1358 -- is a function that returns in place. If the nominal subtype has
1359 -- unknown discriminants, the call still provides constraints on the
1360 -- object, and we have to create an actual subtype from it.
1362 -- If the type is class-wide, the expression is dynamically tagged and
1363 -- we do not create an actual subtype either. Ditto for an interface.
1365 elsif Is_Limited_Type (Exp_Typ)
1367 (Is_Class_Wide_Type (Exp_Typ)
1368 or else Is_Interface (Exp_Typ)
1369 or else not Has_Unknown_Discriminants (Exp_Typ)
1370 or else not Is_Composite_Type (Unc_Type))
1374 -- For limited interfaces, nothing to be done
1376 -- This branch may be redundant once the limited interface issue is
1379 elsif Is_Interface (Exp_Typ)
1380 and then Is_Limited_Interface (Exp_Typ)
1384 -- For limited objects initialized with build in place function calls,
1385 -- nothing to be done; otherwise we prematurely introduce an N_Reference
1386 -- node in the expression initializing the object, which breaks the
1387 -- circuitry that detects and adds the additional arguments to the
1390 elsif Is_Build_In_Place_Function_Call (Exp) then
1394 Remove_Side_Effects (Exp);
1395 Rewrite (Subtype_Indic,
1396 Make_Subtype_From_Expr (Exp, Unc_Type));
1398 end Expand_Subtype_From_Expr;
1400 --------------------
1401 -- Find_Init_Call --
1402 --------------------
1404 function Find_Init_Call
1406 Rep_Clause : Node_Id) return Node_Id
1408 Typ : constant Entity_Id := Etype (Var);
1410 Init_Proc : Entity_Id;
1411 -- Initialization procedure for Typ
1413 function Find_Init_Call_In_List (From : Node_Id) return Node_Id;
1414 -- Look for init call for Var starting at From and scanning the
1415 -- enclosing list until Rep_Clause or the end of the list is reached.
1417 ----------------------------
1418 -- Find_Init_Call_In_List --
1419 ----------------------------
1421 function Find_Init_Call_In_List (From : Node_Id) return Node_Id is
1422 Init_Call : Node_Id;
1426 while Present (Init_Call) and then Init_Call /= Rep_Clause loop
1427 if Nkind (Init_Call) = N_Procedure_Call_Statement
1428 and then Is_Entity_Name (Name (Init_Call))
1429 and then Entity (Name (Init_Call)) = Init_Proc
1437 end Find_Init_Call_In_List;
1439 Init_Call : Node_Id;
1441 -- Start of processing for Find_Init_Call
1444 if not Has_Non_Null_Base_Init_Proc (Typ) then
1445 -- No init proc for the type, so obviously no call to be found
1450 Init_Proc := Base_Init_Proc (Typ);
1452 -- First scan the list containing the declaration of Var
1454 Init_Call := Find_Init_Call_In_List (From => Next (Parent (Var)));
1456 -- If not found, also look on Var's freeze actions list, if any, since
1457 -- the init call may have been moved there (case of an address clause
1458 -- applying to Var).
1460 if No (Init_Call) and then Present (Freeze_Node (Var)) then
1461 Init_Call := Find_Init_Call_In_List
1462 (First (Actions (Freeze_Node (Var))));
1468 ------------------------
1469 -- Find_Interface_ADT --
1470 ------------------------
1472 function Find_Interface_ADT
1474 Iface : Entity_Id) return Elmt_Id
1477 Typ : Entity_Id := T;
1480 pragma Assert (Is_Interface (Iface));
1482 -- Handle private types
1484 if Has_Private_Declaration (Typ)
1485 and then Present (Full_View (Typ))
1487 Typ := Full_View (Typ);
1490 -- Handle access types
1492 if Is_Access_Type (Typ) then
1493 Typ := Directly_Designated_Type (Typ);
1496 -- Handle task and protected types implementing interfaces
1498 if Is_Concurrent_Type (Typ) then
1499 Typ := Corresponding_Record_Type (Typ);
1503 (not Is_Class_Wide_Type (Typ)
1504 and then Ekind (Typ) /= E_Incomplete_Type);
1506 if Is_Ancestor (Iface, Typ) then
1507 return First_Elmt (Access_Disp_Table (Typ));
1511 Next_Elmt (Next_Elmt (First_Elmt (Access_Disp_Table (Typ))));
1513 and then Present (Related_Type (Node (ADT)))
1514 and then Related_Type (Node (ADT)) /= Iface
1515 and then not Is_Ancestor (Iface, Related_Type (Node (ADT)))
1520 pragma Assert (Present (Related_Type (Node (ADT))));
1523 end Find_Interface_ADT;
1525 ------------------------
1526 -- Find_Interface_Tag --
1527 ------------------------
1529 function Find_Interface_Tag
1531 Iface : Entity_Id) return Entity_Id
1534 Found : Boolean := False;
1535 Typ : Entity_Id := T;
1537 procedure Find_Tag (Typ : Entity_Id);
1538 -- Internal subprogram used to recursively climb to the ancestors
1544 procedure Find_Tag (Typ : Entity_Id) is
1549 -- Check if the interface is an immediate ancestor of the type and
1550 -- therefore shares the main tag.
1553 pragma Assert (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
1554 AI_Tag := First_Tag_Component (Typ);
1559 -- Climb to the root type handling private types
1561 if Present (Full_View (Etype (Typ))) then
1562 if Full_View (Etype (Typ)) /= Typ then
1563 Find_Tag (Full_View (Etype (Typ)));
1566 elsif Etype (Typ) /= Typ then
1567 Find_Tag (Etype (Typ));
1570 -- Traverse the list of interfaces implemented by the type
1573 and then Present (Interfaces (Typ))
1574 and then not (Is_Empty_Elmt_List (Interfaces (Typ)))
1576 -- Skip the tag associated with the primary table
1578 pragma Assert (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
1579 AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
1580 pragma Assert (Present (AI_Tag));
1582 AI_Elmt := First_Elmt (Interfaces (Typ));
1583 while Present (AI_Elmt) loop
1584 AI := Node (AI_Elmt);
1586 if AI = Iface or else Is_Ancestor (Iface, AI) then
1591 AI_Tag := Next_Tag_Component (AI_Tag);
1592 Next_Elmt (AI_Elmt);
1597 -- Start of processing for Find_Interface_Tag
1600 pragma Assert (Is_Interface (Iface));
1602 -- Handle access types
1604 if Is_Access_Type (Typ) then
1605 Typ := Directly_Designated_Type (Typ);
1608 -- Handle class-wide types
1610 if Is_Class_Wide_Type (Typ) then
1611 Typ := Root_Type (Typ);
1614 -- Handle private types
1616 if Has_Private_Declaration (Typ)
1617 and then Present (Full_View (Typ))
1619 Typ := Full_View (Typ);
1622 -- Handle entities from the limited view
1624 if Ekind (Typ) = E_Incomplete_Type then
1625 pragma Assert (Present (Non_Limited_View (Typ)));
1626 Typ := Non_Limited_View (Typ);
1629 -- Handle task and protected types implementing interfaces
1631 if Is_Concurrent_Type (Typ) then
1632 Typ := Corresponding_Record_Type (Typ);
1636 pragma Assert (Found);
1638 end Find_Interface_Tag;
1644 function Find_Prim_Op (T : Entity_Id; Name : Name_Id) return Entity_Id is
1646 Typ : Entity_Id := T;
1650 if Is_Class_Wide_Type (Typ) then
1651 Typ := Root_Type (Typ);
1654 Typ := Underlying_Type (Typ);
1656 -- Loop through primitive operations
1658 Prim := First_Elmt (Primitive_Operations (Typ));
1659 while Present (Prim) loop
1662 -- We can retrieve primitive operations by name if it is an internal
1663 -- name. For equality we must check that both of its operands have
1664 -- the same type, to avoid confusion with user-defined equalities
1665 -- than may have a non-symmetric signature.
1667 exit when Chars (Op) = Name
1670 or else Etype (First_Entity (Op)) = Etype (Last_Entity (Op)));
1674 -- Raise Program_Error if no primitive found
1677 raise Program_Error;
1688 function Find_Prim_Op
1690 Name : TSS_Name_Type) return Entity_Id
1693 Typ : Entity_Id := T;
1696 if Is_Class_Wide_Type (Typ) then
1697 Typ := Root_Type (Typ);
1700 Typ := Underlying_Type (Typ);
1702 Prim := First_Elmt (Primitive_Operations (Typ));
1703 while not Is_TSS (Node (Prim), Name) loop
1706 -- Raise program error if no primitive found
1709 raise Program_Error;
1716 ----------------------------
1717 -- Find_Protection_Object --
1718 ----------------------------
1720 function Find_Protection_Object (Scop : Entity_Id) return Entity_Id is
1725 while Present (S) loop
1726 if (Ekind (S) = E_Entry
1727 or else Ekind (S) = E_Entry_Family
1728 or else Ekind (S) = E_Function
1729 or else Ekind (S) = E_Procedure)
1730 and then Present (Protection_Object (S))
1732 return Protection_Object (S);
1738 -- If we do not find a Protection object in the scope chain, then
1739 -- something has gone wrong, most likely the object was never created.
1741 raise Program_Error;
1742 end Find_Protection_Object;
1744 ----------------------
1745 -- Force_Evaluation --
1746 ----------------------
1748 procedure Force_Evaluation (Exp : Node_Id; Name_Req : Boolean := False) is
1750 Remove_Side_Effects (Exp, Name_Req, Variable_Ref => True);
1751 end Force_Evaluation;
1753 ------------------------
1754 -- Generate_Poll_Call --
1755 ------------------------
1757 procedure Generate_Poll_Call (N : Node_Id) is
1759 -- No poll call if polling not active
1761 if not Polling_Required then
1764 -- Otherwise generate require poll call
1767 Insert_Before_And_Analyze (N,
1768 Make_Procedure_Call_Statement (Sloc (N),
1769 Name => New_Occurrence_Of (RTE (RE_Poll), Sloc (N))));
1771 end Generate_Poll_Call;
1773 ---------------------------------
1774 -- Get_Current_Value_Condition --
1775 ---------------------------------
1777 -- Note: the implementation of this procedure is very closely tied to the
1778 -- implementation of Set_Current_Value_Condition. In the Get procedure, we
1779 -- interpret Current_Value fields set by the Set procedure, so the two
1780 -- procedures need to be closely coordinated.
1782 procedure Get_Current_Value_Condition
1787 Loc : constant Source_Ptr := Sloc (Var);
1788 Ent : constant Entity_Id := Entity (Var);
1790 procedure Process_Current_Value_Condition
1793 -- N is an expression which holds either True (S = True) or False (S =
1794 -- False) in the condition. This procedure digs out the expression and
1795 -- if it refers to Ent, sets Op and Val appropriately.
1797 -------------------------------------
1798 -- Process_Current_Value_Condition --
1799 -------------------------------------
1801 procedure Process_Current_Value_Condition
1812 -- Deal with NOT operators, inverting sense
1814 while Nkind (Cond) = N_Op_Not loop
1815 Cond := Right_Opnd (Cond);
1819 -- Deal with AND THEN and AND cases
1821 if Nkind (Cond) = N_And_Then
1822 or else Nkind (Cond) = N_Op_And
1824 -- Don't ever try to invert a condition that is of the form
1825 -- of an AND or AND THEN (since we are not doing sufficiently
1826 -- general processing to allow this).
1828 if Sens = False then
1834 -- Recursively process AND and AND THEN branches
1836 Process_Current_Value_Condition (Left_Opnd (Cond), True);
1838 if Op /= N_Empty then
1842 Process_Current_Value_Condition (Right_Opnd (Cond), True);
1845 -- Case of relational operator
1847 elsif Nkind (Cond) in N_Op_Compare then
1850 -- Invert sense of test if inverted test
1852 if Sens = False then
1854 when N_Op_Eq => Op := N_Op_Ne;
1855 when N_Op_Ne => Op := N_Op_Eq;
1856 when N_Op_Lt => Op := N_Op_Ge;
1857 when N_Op_Gt => Op := N_Op_Le;
1858 when N_Op_Le => Op := N_Op_Gt;
1859 when N_Op_Ge => Op := N_Op_Lt;
1860 when others => raise Program_Error;
1864 -- Case of entity op value
1866 if Is_Entity_Name (Left_Opnd (Cond))
1867 and then Ent = Entity (Left_Opnd (Cond))
1868 and then Compile_Time_Known_Value (Right_Opnd (Cond))
1870 Val := Right_Opnd (Cond);
1872 -- Case of value op entity
1874 elsif Is_Entity_Name (Right_Opnd (Cond))
1875 and then Ent = Entity (Right_Opnd (Cond))
1876 and then Compile_Time_Known_Value (Left_Opnd (Cond))
1878 Val := Left_Opnd (Cond);
1880 -- We are effectively swapping operands
1883 when N_Op_Eq => null;
1884 when N_Op_Ne => null;
1885 when N_Op_Lt => Op := N_Op_Gt;
1886 when N_Op_Gt => Op := N_Op_Lt;
1887 when N_Op_Le => Op := N_Op_Ge;
1888 when N_Op_Ge => Op := N_Op_Le;
1889 when others => raise Program_Error;
1898 -- Case of Boolean variable reference, return as though the
1899 -- reference had said var = True.
1902 if Is_Entity_Name (Cond)
1903 and then Ent = Entity (Cond)
1905 Val := New_Occurrence_Of (Standard_True, Sloc (Cond));
1907 if Sens = False then
1914 end Process_Current_Value_Condition;
1916 -- Start of processing for Get_Current_Value_Condition
1922 -- Immediate return, nothing doing, if this is not an object
1924 if Ekind (Ent) not in Object_Kind then
1928 -- Otherwise examine current value
1931 CV : constant Node_Id := Current_Value (Ent);
1936 -- If statement. Condition is known true in THEN section, known False
1937 -- in any ELSIF or ELSE part, and unknown outside the IF statement.
1939 if Nkind (CV) = N_If_Statement then
1941 -- Before start of IF statement
1943 if Loc < Sloc (CV) then
1946 -- After end of IF statement
1948 elsif Loc >= Sloc (CV) + Text_Ptr (UI_To_Int (End_Span (CV))) then
1952 -- At this stage we know that we are within the IF statement, but
1953 -- unfortunately, the tree does not record the SLOC of the ELSE so
1954 -- we cannot use a simple SLOC comparison to distinguish between
1955 -- the then/else statements, so we have to climb the tree.
1962 while Parent (N) /= CV loop
1965 -- If we fall off the top of the tree, then that's odd, but
1966 -- perhaps it could occur in some error situation, and the
1967 -- safest response is simply to assume that the outcome of
1968 -- the condition is unknown. No point in bombing during an
1969 -- attempt to optimize things.
1976 -- Now we have N pointing to a node whose parent is the IF
1977 -- statement in question, so now we can tell if we are within
1978 -- the THEN statements.
1980 if Is_List_Member (N)
1981 and then List_Containing (N) = Then_Statements (CV)
1985 -- If the variable reference does not come from source, we
1986 -- cannot reliably tell whether it appears in the else part.
1987 -- In particular, if it appears in generated code for a node
1988 -- that requires finalization, it may be attached to a list
1989 -- that has not been yet inserted into the code. For now,
1990 -- treat it as unknown.
1992 elsif not Comes_From_Source (N) then
1995 -- Otherwise we must be in ELSIF or ELSE part
2002 -- ELSIF part. Condition is known true within the referenced
2003 -- ELSIF, known False in any subsequent ELSIF or ELSE part, and
2004 -- unknown before the ELSE part or after the IF statement.
2006 elsif Nkind (CV) = N_Elsif_Part then
2009 -- Before start of ELSIF part
2011 if Loc < Sloc (CV) then
2014 -- After end of IF statement
2016 elsif Loc >= Sloc (Stm) +
2017 Text_Ptr (UI_To_Int (End_Span (Stm)))
2022 -- Again we lack the SLOC of the ELSE, so we need to climb the
2023 -- tree to see if we are within the ELSIF part in question.
2030 while Parent (N) /= Stm loop
2033 -- If we fall off the top of the tree, then that's odd, but
2034 -- perhaps it could occur in some error situation, and the
2035 -- safest response is simply to assume that the outcome of
2036 -- the condition is unknown. No point in bombing during an
2037 -- attempt to optimize things.
2044 -- Now we have N pointing to a node whose parent is the IF
2045 -- statement in question, so see if is the ELSIF part we want.
2046 -- the THEN statements.
2051 -- Otherwise we must be in subsequent ELSIF or ELSE part
2058 -- Iteration scheme of while loop. The condition is known to be
2059 -- true within the body of the loop.
2061 elsif Nkind (CV) = N_Iteration_Scheme then
2063 Loop_Stmt : constant Node_Id := Parent (CV);
2066 -- Before start of body of loop
2068 if Loc < Sloc (Loop_Stmt) then
2071 -- After end of LOOP statement
2073 elsif Loc >= Sloc (End_Label (Loop_Stmt)) then
2076 -- We are within the body of the loop
2083 -- All other cases of Current_Value settings
2089 -- If we fall through here, then we have a reportable condition, Sens
2090 -- is True if the condition is true and False if it needs inverting.
2092 Process_Current_Value_Condition (Condition (CV), Sens);
2094 end Get_Current_Value_Condition;
2096 ---------------------------------
2097 -- Has_Controlled_Coextensions --
2098 ---------------------------------
2100 function Has_Controlled_Coextensions (Typ : Entity_Id) return Boolean is
2105 -- Only consider record types
2107 if Ekind (Typ) /= E_Record_Type
2108 and then Ekind (Typ) /= E_Record_Subtype
2113 if Has_Discriminants (Typ) then
2114 Discr := First_Discriminant (Typ);
2115 while Present (Discr) loop
2116 D_Typ := Etype (Discr);
2118 if Ekind (D_Typ) = E_Anonymous_Access_Type
2120 (Is_Controlled (Directly_Designated_Type (D_Typ))
2122 Is_Concurrent_Type (Directly_Designated_Type (D_Typ)))
2127 Next_Discriminant (Discr);
2132 end Has_Controlled_Coextensions;
2134 --------------------
2135 -- Homonym_Number --
2136 --------------------
2138 function Homonym_Number (Subp : Entity_Id) return Nat is
2144 Hom := Homonym (Subp);
2145 while Present (Hom) loop
2146 if Scope (Hom) = Scope (Subp) then
2150 Hom := Homonym (Hom);
2156 ------------------------------
2157 -- In_Unconditional_Context --
2158 ------------------------------
2160 function In_Unconditional_Context (Node : Node_Id) return Boolean is
2165 while Present (P) loop
2167 when N_Subprogram_Body =>
2170 when N_If_Statement =>
2173 when N_Loop_Statement =>
2176 when N_Case_Statement =>
2185 end In_Unconditional_Context;
2191 procedure Insert_Action (Assoc_Node : Node_Id; Ins_Action : Node_Id) is
2193 if Present (Ins_Action) then
2194 Insert_Actions (Assoc_Node, New_List (Ins_Action));
2198 -- Version with check(s) suppressed
2200 procedure Insert_Action
2201 (Assoc_Node : Node_Id; Ins_Action : Node_Id; Suppress : Check_Id)
2204 Insert_Actions (Assoc_Node, New_List (Ins_Action), Suppress);
2207 --------------------
2208 -- Insert_Actions --
2209 --------------------
2211 procedure Insert_Actions (Assoc_Node : Node_Id; Ins_Actions : List_Id) is
2215 Wrapped_Node : Node_Id := Empty;
2218 if No (Ins_Actions) or else Is_Empty_List (Ins_Actions) then
2222 -- Ignore insert of actions from inside default expression (or other
2223 -- similar "spec expression") in the special spec-expression analyze
2224 -- mode. Any insertions at this point have no relevance, since we are
2225 -- only doing the analyze to freeze the types of any static expressions.
2226 -- See section "Handling of Default Expressions" in the spec of package
2227 -- Sem for further details.
2229 if In_Spec_Expression then
2233 -- If the action derives from stuff inside a record, then the actions
2234 -- are attached to the current scope, to be inserted and analyzed on
2235 -- exit from the scope. The reason for this is that we may also
2236 -- be generating freeze actions at the same time, and they must
2237 -- eventually be elaborated in the correct order.
2239 if Is_Record_Type (Current_Scope)
2240 and then not Is_Frozen (Current_Scope)
2242 if No (Scope_Stack.Table
2243 (Scope_Stack.Last).Pending_Freeze_Actions)
2245 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions :=
2250 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions);
2256 -- We now intend to climb up the tree to find the right point to
2257 -- insert the actions. We start at Assoc_Node, unless this node is
2258 -- a subexpression in which case we start with its parent. We do this
2259 -- for two reasons. First it speeds things up. Second, if Assoc_Node
2260 -- is itself one of the special nodes like N_And_Then, then we assume
2261 -- that an initial request to insert actions for such a node does not
2262 -- expect the actions to get deposited in the node for later handling
2263 -- when the node is expanded, since clearly the node is being dealt
2264 -- with by the caller. Note that in the subexpression case, N is
2265 -- always the child we came from.
2267 -- N_Raise_xxx_Error is an annoying special case, it is a statement
2268 -- if it has type Standard_Void_Type, and a subexpression otherwise.
2269 -- otherwise. Procedure attribute references are also statements.
2271 if Nkind (Assoc_Node) in N_Subexpr
2272 and then (Nkind (Assoc_Node) in N_Raise_xxx_Error
2273 or else Etype (Assoc_Node) /= Standard_Void_Type)
2274 and then (Nkind (Assoc_Node) /= N_Attribute_Reference
2276 not Is_Procedure_Attribute_Name
2277 (Attribute_Name (Assoc_Node)))
2279 P := Assoc_Node; -- ??? does not agree with above!
2280 N := Parent (Assoc_Node);
2282 -- Non-subexpression case. Note that N is initially Empty in this
2283 -- case (N is only guaranteed Non-Empty in the subexpr case).
2290 -- Capture root of the transient scope
2292 if Scope_Is_Transient then
2293 Wrapped_Node := Node_To_Be_Wrapped;
2297 pragma Assert (Present (P));
2301 -- Case of right operand of AND THEN or OR ELSE. Put the actions
2302 -- in the Actions field of the right operand. They will be moved
2303 -- out further when the AND THEN or OR ELSE operator is expanded.
2304 -- Nothing special needs to be done for the left operand since
2305 -- in that case the actions are executed unconditionally.
2307 when N_Short_Circuit =>
2308 if N = Right_Opnd (P) then
2310 -- We are now going to either append the actions to the
2311 -- actions field of the short-circuit operation. We will
2312 -- also analyze the actions now.
2314 -- This analysis is really too early, the proper thing would
2315 -- be to just park them there now, and only analyze them if
2316 -- we find we really need them, and to it at the proper
2317 -- final insertion point. However attempting to this proved
2318 -- tricky, so for now we just kill current values before and
2319 -- after the analyze call to make sure we avoid peculiar
2320 -- optimizations from this out of order insertion.
2322 Kill_Current_Values;
2324 if Present (Actions (P)) then
2325 Insert_List_After_And_Analyze
2326 (Last (Actions (P)), Ins_Actions);
2328 Set_Actions (P, Ins_Actions);
2329 Analyze_List (Actions (P));
2332 Kill_Current_Values;
2337 -- Then or Else operand of conditional expression. Add actions to
2338 -- Then_Actions or Else_Actions field as appropriate. The actions
2339 -- will be moved further out when the conditional is expanded.
2341 when N_Conditional_Expression =>
2343 ThenX : constant Node_Id := Next (First (Expressions (P)));
2344 ElseX : constant Node_Id := Next (ThenX);
2347 -- Actions belong to the then expression, temporarily
2348 -- place them as Then_Actions of the conditional expr.
2349 -- They will be moved to the proper place later when
2350 -- the conditional expression is expanded.
2353 if Present (Then_Actions (P)) then
2354 Insert_List_After_And_Analyze
2355 (Last (Then_Actions (P)), Ins_Actions);
2357 Set_Then_Actions (P, Ins_Actions);
2358 Analyze_List (Then_Actions (P));
2363 -- Actions belong to the else expression, temporarily
2364 -- place them as Else_Actions of the conditional expr.
2365 -- They will be moved to the proper place later when
2366 -- the conditional expression is expanded.
2368 elsif N = ElseX then
2369 if Present (Else_Actions (P)) then
2370 Insert_List_After_And_Analyze
2371 (Last (Else_Actions (P)), Ins_Actions);
2373 Set_Else_Actions (P, Ins_Actions);
2374 Analyze_List (Else_Actions (P));
2379 -- Actions belong to the condition. In this case they are
2380 -- unconditionally executed, and so we can continue the
2381 -- search for the proper insert point.
2388 -- Case of appearing in the condition of a while expression or
2389 -- elsif. We insert the actions into the Condition_Actions field.
2390 -- They will be moved further out when the while loop or elsif
2393 when N_Iteration_Scheme |
2396 if N = Condition (P) then
2397 if Present (Condition_Actions (P)) then
2398 Insert_List_After_And_Analyze
2399 (Last (Condition_Actions (P)), Ins_Actions);
2401 Set_Condition_Actions (P, Ins_Actions);
2403 -- Set the parent of the insert actions explicitly.
2404 -- This is not a syntactic field, but we need the
2405 -- parent field set, in particular so that freeze
2406 -- can understand that it is dealing with condition
2407 -- actions, and properly insert the freezing actions.
2409 Set_Parent (Ins_Actions, P);
2410 Analyze_List (Condition_Actions (P));
2416 -- Statements, declarations, pragmas, representation clauses
2421 N_Procedure_Call_Statement |
2422 N_Statement_Other_Than_Procedure_Call |
2428 -- Representation_Clause
2431 N_Attribute_Definition_Clause |
2432 N_Enumeration_Representation_Clause |
2433 N_Record_Representation_Clause |
2437 N_Abstract_Subprogram_Declaration |
2439 N_Exception_Declaration |
2440 N_Exception_Renaming_Declaration |
2441 N_Formal_Abstract_Subprogram_Declaration |
2442 N_Formal_Concrete_Subprogram_Declaration |
2443 N_Formal_Object_Declaration |
2444 N_Formal_Type_Declaration |
2445 N_Full_Type_Declaration |
2446 N_Function_Instantiation |
2447 N_Generic_Function_Renaming_Declaration |
2448 N_Generic_Package_Declaration |
2449 N_Generic_Package_Renaming_Declaration |
2450 N_Generic_Procedure_Renaming_Declaration |
2451 N_Generic_Subprogram_Declaration |
2452 N_Implicit_Label_Declaration |
2453 N_Incomplete_Type_Declaration |
2454 N_Number_Declaration |
2455 N_Object_Declaration |
2456 N_Object_Renaming_Declaration |
2458 N_Package_Body_Stub |
2459 N_Package_Declaration |
2460 N_Package_Instantiation |
2461 N_Package_Renaming_Declaration |
2462 N_Private_Extension_Declaration |
2463 N_Private_Type_Declaration |
2464 N_Procedure_Instantiation |
2466 N_Protected_Body_Stub |
2467 N_Protected_Type_Declaration |
2468 N_Single_Task_Declaration |
2470 N_Subprogram_Body_Stub |
2471 N_Subprogram_Declaration |
2472 N_Subprogram_Renaming_Declaration |
2473 N_Subtype_Declaration |
2476 N_Task_Type_Declaration |
2478 -- Freeze entity behaves like a declaration or statement
2482 -- Do not insert here if the item is not a list member (this
2483 -- happens for example with a triggering statement, and the
2484 -- proper approach is to insert before the entire select).
2486 if not Is_List_Member (P) then
2489 -- Do not insert if parent of P is an N_Component_Association
2490 -- node (i.e. we are in the context of an N_Aggregate or
2491 -- N_Extension_Aggregate node. In this case we want to insert
2492 -- before the entire aggregate.
2494 elsif Nkind (Parent (P)) = N_Component_Association then
2497 -- Do not insert if the parent of P is either an N_Variant
2498 -- node or an N_Record_Definition node, meaning in either
2499 -- case that P is a member of a component list, and that
2500 -- therefore the actions should be inserted outside the
2501 -- complete record declaration.
2503 elsif Nkind (Parent (P)) = N_Variant
2504 or else Nkind (Parent (P)) = N_Record_Definition
2508 -- Do not insert freeze nodes within the loop generated for
2509 -- an aggregate, because they may be elaborated too late for
2510 -- subsequent use in the back end: within a package spec the
2511 -- loop is part of the elaboration procedure and is only
2512 -- elaborated during the second pass.
2513 -- If the loop comes from source, or the entity is local to
2514 -- the loop itself it must remain within.
2516 elsif Nkind (Parent (P)) = N_Loop_Statement
2517 and then not Comes_From_Source (Parent (P))
2518 and then Nkind (First (Ins_Actions)) = N_Freeze_Entity
2520 Scope (Entity (First (Ins_Actions))) /= Current_Scope
2524 -- Otherwise we can go ahead and do the insertion
2526 elsif P = Wrapped_Node then
2527 Store_Before_Actions_In_Scope (Ins_Actions);
2531 Insert_List_Before_And_Analyze (P, Ins_Actions);
2535 -- A special case, N_Raise_xxx_Error can act either as a
2536 -- statement or a subexpression. We tell the difference
2537 -- by looking at the Etype. It is set to Standard_Void_Type
2538 -- in the statement case.
2541 N_Raise_xxx_Error =>
2542 if Etype (P) = Standard_Void_Type then
2543 if P = Wrapped_Node then
2544 Store_Before_Actions_In_Scope (Ins_Actions);
2546 Insert_List_Before_And_Analyze (P, Ins_Actions);
2551 -- In the subexpression case, keep climbing
2557 -- If a component association appears within a loop created for
2558 -- an array aggregate, attach the actions to the association so
2559 -- they can be subsequently inserted within the loop. For other
2560 -- component associations insert outside of the aggregate. For
2561 -- an association that will generate a loop, its Loop_Actions
2562 -- attribute is already initialized (see exp_aggr.adb).
2564 -- The list of loop_actions can in turn generate additional ones,
2565 -- that are inserted before the associated node. If the associated
2566 -- node is outside the aggregate, the new actions are collected
2567 -- at the end of the loop actions, to respect the order in which
2568 -- they are to be elaborated.
2571 N_Component_Association =>
2572 if Nkind (Parent (P)) = N_Aggregate
2573 and then Present (Loop_Actions (P))
2575 if Is_Empty_List (Loop_Actions (P)) then
2576 Set_Loop_Actions (P, Ins_Actions);
2577 Analyze_List (Ins_Actions);
2584 -- Check whether these actions were generated
2585 -- by a declaration that is part of the loop_
2586 -- actions for the component_association.
2589 while Present (Decl) loop
2590 exit when Parent (Decl) = P
2591 and then Is_List_Member (Decl)
2593 List_Containing (Decl) = Loop_Actions (P);
2594 Decl := Parent (Decl);
2597 if Present (Decl) then
2598 Insert_List_Before_And_Analyze
2599 (Decl, Ins_Actions);
2601 Insert_List_After_And_Analyze
2602 (Last (Loop_Actions (P)), Ins_Actions);
2613 -- Another special case, an attribute denoting a procedure call
2616 N_Attribute_Reference =>
2617 if Is_Procedure_Attribute_Name (Attribute_Name (P)) then
2618 if P = Wrapped_Node then
2619 Store_Before_Actions_In_Scope (Ins_Actions);
2621 Insert_List_Before_And_Analyze (P, Ins_Actions);
2626 -- In the subexpression case, keep climbing
2632 -- For all other node types, keep climbing tree
2636 N_Accept_Alternative |
2637 N_Access_Definition |
2638 N_Access_Function_Definition |
2639 N_Access_Procedure_Definition |
2640 N_Access_To_Object_Definition |
2643 N_Case_Statement_Alternative |
2644 N_Character_Literal |
2645 N_Compilation_Unit |
2646 N_Compilation_Unit_Aux |
2647 N_Component_Clause |
2648 N_Component_Declaration |
2649 N_Component_Definition |
2651 N_Constrained_Array_Definition |
2652 N_Decimal_Fixed_Point_Definition |
2653 N_Defining_Character_Literal |
2654 N_Defining_Identifier |
2655 N_Defining_Operator_Symbol |
2656 N_Defining_Program_Unit_Name |
2657 N_Delay_Alternative |
2658 N_Delta_Constraint |
2659 N_Derived_Type_Definition |
2661 N_Digits_Constraint |
2662 N_Discriminant_Association |
2663 N_Discriminant_Specification |
2665 N_Entry_Body_Formal_Part |
2666 N_Entry_Call_Alternative |
2667 N_Entry_Declaration |
2668 N_Entry_Index_Specification |
2669 N_Enumeration_Type_Definition |
2671 N_Exception_Handler |
2673 N_Explicit_Dereference |
2674 N_Extension_Aggregate |
2675 N_Floating_Point_Definition |
2676 N_Formal_Decimal_Fixed_Point_Definition |
2677 N_Formal_Derived_Type_Definition |
2678 N_Formal_Discrete_Type_Definition |
2679 N_Formal_Floating_Point_Definition |
2680 N_Formal_Modular_Type_Definition |
2681 N_Formal_Ordinary_Fixed_Point_Definition |
2682 N_Formal_Package_Declaration |
2683 N_Formal_Private_Type_Definition |
2684 N_Formal_Signed_Integer_Type_Definition |
2686 N_Function_Specification |
2687 N_Generic_Association |
2688 N_Handled_Sequence_Of_Statements |
2691 N_Index_Or_Discriminant_Constraint |
2692 N_Indexed_Component |
2696 N_Loop_Parameter_Specification |
2698 N_Modular_Type_Definition |
2724 N_Op_Shift_Right_Arithmetic |
2728 N_Ordinary_Fixed_Point_Definition |
2730 N_Package_Specification |
2731 N_Parameter_Association |
2732 N_Parameter_Specification |
2733 N_Pop_Constraint_Error_Label |
2734 N_Pop_Program_Error_Label |
2735 N_Pop_Storage_Error_Label |
2736 N_Pragma_Argument_Association |
2737 N_Procedure_Specification |
2738 N_Protected_Definition |
2739 N_Push_Constraint_Error_Label |
2740 N_Push_Program_Error_Label |
2741 N_Push_Storage_Error_Label |
2742 N_Qualified_Expression |
2744 N_Range_Constraint |
2746 N_Real_Range_Specification |
2747 N_Record_Definition |
2749 N_Selected_Component |
2750 N_Signed_Integer_Type_Definition |
2751 N_Single_Protected_Declaration |
2755 N_Subtype_Indication |
2758 N_Terminate_Alternative |
2759 N_Triggering_Alternative |
2761 N_Unchecked_Expression |
2762 N_Unchecked_Type_Conversion |
2763 N_Unconstrained_Array_Definition |
2766 N_Use_Package_Clause |
2770 N_Validate_Unchecked_Conversion |
2777 -- Make sure that inserted actions stay in the transient scope
2779 if P = Wrapped_Node then
2780 Store_Before_Actions_In_Scope (Ins_Actions);
2784 -- If we fall through above tests, keep climbing tree
2788 if Nkind (Parent (N)) = N_Subunit then
2790 -- This is the proper body corresponding to a stub. Insertion
2791 -- must be done at the point of the stub, which is in the decla-
2792 -- rative part of the parent unit.
2794 P := Corresponding_Stub (Parent (N));
2802 -- Version with check(s) suppressed
2804 procedure Insert_Actions
2805 (Assoc_Node : Node_Id;
2806 Ins_Actions : List_Id;
2807 Suppress : Check_Id)
2810 if Suppress = All_Checks then
2812 Svg : constant Suppress_Array := Scope_Suppress;
2814 Scope_Suppress := (others => True);
2815 Insert_Actions (Assoc_Node, Ins_Actions);
2816 Scope_Suppress := Svg;
2821 Svg : constant Boolean := Scope_Suppress (Suppress);
2823 Scope_Suppress (Suppress) := True;
2824 Insert_Actions (Assoc_Node, Ins_Actions);
2825 Scope_Suppress (Suppress) := Svg;
2830 --------------------------
2831 -- Insert_Actions_After --
2832 --------------------------
2834 procedure Insert_Actions_After
2835 (Assoc_Node : Node_Id;
2836 Ins_Actions : List_Id)
2839 if Scope_Is_Transient
2840 and then Assoc_Node = Node_To_Be_Wrapped
2842 Store_After_Actions_In_Scope (Ins_Actions);
2844 Insert_List_After_And_Analyze (Assoc_Node, Ins_Actions);
2846 end Insert_Actions_After;
2848 ---------------------------------
2849 -- Insert_Library_Level_Action --
2850 ---------------------------------
2852 procedure Insert_Library_Level_Action (N : Node_Id) is
2853 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2856 Push_Scope (Cunit_Entity (Main_Unit));
2857 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
2859 if No (Actions (Aux)) then
2860 Set_Actions (Aux, New_List (N));
2862 Append (N, Actions (Aux));
2867 end Insert_Library_Level_Action;
2869 ----------------------------------
2870 -- Insert_Library_Level_Actions --
2871 ----------------------------------
2873 procedure Insert_Library_Level_Actions (L : List_Id) is
2874 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2877 if Is_Non_Empty_List (L) then
2878 Push_Scope (Cunit_Entity (Main_Unit));
2879 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
2881 if No (Actions (Aux)) then
2882 Set_Actions (Aux, L);
2885 Insert_List_After_And_Analyze (Last (Actions (Aux)), L);
2890 end Insert_Library_Level_Actions;
2892 ----------------------
2893 -- Inside_Init_Proc --
2894 ----------------------
2896 function Inside_Init_Proc return Boolean is
2902 and then S /= Standard_Standard
2904 if Is_Init_Proc (S) then
2912 end Inside_Init_Proc;
2914 ----------------------------
2915 -- Is_All_Null_Statements --
2916 ----------------------------
2918 function Is_All_Null_Statements (L : List_Id) return Boolean is
2923 while Present (Stm) loop
2924 if Nkind (Stm) /= N_Null_Statement then
2932 end Is_All_Null_Statements;
2934 ----------------------------------
2935 -- Is_Library_Level_Tagged_Type --
2936 ----------------------------------
2938 function Is_Library_Level_Tagged_Type (Typ : Entity_Id) return Boolean is
2940 return Is_Tagged_Type (Typ)
2941 and then Is_Library_Level_Entity (Typ);
2942 end Is_Library_Level_Tagged_Type;
2944 ----------------------------------
2945 -- Is_Possibly_Unaligned_Object --
2946 ----------------------------------
2948 function Is_Possibly_Unaligned_Object (N : Node_Id) return Boolean is
2949 T : constant Entity_Id := Etype (N);
2952 -- If renamed object, apply test to underlying object
2954 if Is_Entity_Name (N)
2955 and then Is_Object (Entity (N))
2956 and then Present (Renamed_Object (Entity (N)))
2958 return Is_Possibly_Unaligned_Object (Renamed_Object (Entity (N)));
2961 -- Tagged and controlled types and aliased types are always aligned,
2962 -- as are concurrent types.
2965 or else Has_Controlled_Component (T)
2966 or else Is_Concurrent_Type (T)
2967 or else Is_Tagged_Type (T)
2968 or else Is_Controlled (T)
2973 -- If this is an element of a packed array, may be unaligned
2975 if Is_Ref_To_Bit_Packed_Array (N) then
2979 -- Case of component reference
2981 if Nkind (N) = N_Selected_Component then
2983 P : constant Node_Id := Prefix (N);
2984 C : constant Entity_Id := Entity (Selector_Name (N));
2989 -- If component reference is for an array with non-static bounds,
2990 -- then it is always aligned: we can only process unaligned
2991 -- arrays with static bounds (more accurately bounds known at
2994 if Is_Array_Type (T)
2995 and then not Compile_Time_Known_Bounds (T)
3000 -- If component is aliased, it is definitely properly aligned
3002 if Is_Aliased (C) then
3006 -- If component is for a type implemented as a scalar, and the
3007 -- record is packed, and the component is other than the first
3008 -- component of the record, then the component may be unaligned.
3010 if Is_Packed (Etype (P))
3011 and then Represented_As_Scalar (Etype (C))
3012 and then First_Entity (Scope (C)) /= C
3017 -- Compute maximum possible alignment for T
3019 -- If alignment is known, then that settles things
3021 if Known_Alignment (T) then
3022 M := UI_To_Int (Alignment (T));
3024 -- If alignment is not known, tentatively set max alignment
3027 M := Ttypes.Maximum_Alignment;
3029 -- We can reduce this if the Esize is known since the default
3030 -- alignment will never be more than the smallest power of 2
3031 -- that does not exceed this Esize value.
3033 if Known_Esize (T) then
3034 S := UI_To_Int (Esize (T));
3036 while (M / 2) >= S loop
3042 -- If the component reference is for a record that has a specified
3043 -- alignment, and we either know it is too small, or cannot tell,
3044 -- then the component may be unaligned
3046 if Known_Alignment (Etype (P))
3047 and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment
3048 and then M > Alignment (Etype (P))
3053 -- Case of component clause present which may specify an
3054 -- unaligned position.
3056 if Present (Component_Clause (C)) then
3058 -- Otherwise we can do a test to make sure that the actual
3059 -- start position in the record, and the length, are both
3060 -- consistent with the required alignment. If not, we know
3061 -- that we are unaligned.
3064 Align_In_Bits : constant Nat := M * System_Storage_Unit;
3066 if Component_Bit_Offset (C) mod Align_In_Bits /= 0
3067 or else Esize (C) mod Align_In_Bits /= 0
3074 -- Otherwise, for a component reference, test prefix
3076 return Is_Possibly_Unaligned_Object (P);
3079 -- If not a component reference, must be aligned
3084 end Is_Possibly_Unaligned_Object;
3086 ---------------------------------
3087 -- Is_Possibly_Unaligned_Slice --
3088 ---------------------------------
3090 function Is_Possibly_Unaligned_Slice (N : Node_Id) return Boolean is
3092 -- Go to renamed object
3094 if Is_Entity_Name (N)
3095 and then Is_Object (Entity (N))
3096 and then Present (Renamed_Object (Entity (N)))
3098 return Is_Possibly_Unaligned_Slice (Renamed_Object (Entity (N)));
3101 -- The reference must be a slice
3103 if Nkind (N) /= N_Slice then
3107 -- Always assume the worst for a nested record component with a
3108 -- component clause, which gigi/gcc does not appear to handle well.
3109 -- It is not clear why this special test is needed at all ???
3111 if Nkind (Prefix (N)) = N_Selected_Component
3112 and then Nkind (Prefix (Prefix (N))) = N_Selected_Component
3114 Present (Component_Clause (Entity (Selector_Name (Prefix (N)))))
3119 -- We only need to worry if the target has strict alignment
3121 if not Target_Strict_Alignment then
3125 -- If it is a slice, then look at the array type being sliced
3128 Sarr : constant Node_Id := Prefix (N);
3129 -- Prefix of the slice, i.e. the array being sliced
3131 Styp : constant Entity_Id := Etype (Prefix (N));
3132 -- Type of the array being sliced
3138 -- The problems arise if the array object that is being sliced
3139 -- is a component of a record or array, and we cannot guarantee
3140 -- the alignment of the array within its containing object.
3142 -- To investigate this, we look at successive prefixes to see
3143 -- if we have a worrisome indexed or selected component.
3147 -- Case of array is part of an indexed component reference
3149 if Nkind (Pref) = N_Indexed_Component then
3150 Ptyp := Etype (Prefix (Pref));
3152 -- The only problematic case is when the array is packed,
3153 -- in which case we really know nothing about the alignment
3154 -- of individual components.
3156 if Is_Bit_Packed_Array (Ptyp) then
3160 -- Case of array is part of a selected component reference
3162 elsif Nkind (Pref) = N_Selected_Component then
3163 Ptyp := Etype (Prefix (Pref));
3165 -- We are definitely in trouble if the record in question
3166 -- has an alignment, and either we know this alignment is
3167 -- inconsistent with the alignment of the slice, or we
3168 -- don't know what the alignment of the slice should be.
3170 if Known_Alignment (Ptyp)
3171 and then (Unknown_Alignment (Styp)
3172 or else Alignment (Styp) > Alignment (Ptyp))
3177 -- We are in potential trouble if the record type is packed.
3178 -- We could special case when we know that the array is the
3179 -- first component, but that's not such a simple case ???
3181 if Is_Packed (Ptyp) then
3185 -- We are in trouble if there is a component clause, and
3186 -- either we do not know the alignment of the slice, or
3187 -- the alignment of the slice is inconsistent with the
3188 -- bit position specified by the component clause.
3191 Field : constant Entity_Id := Entity (Selector_Name (Pref));
3193 if Present (Component_Clause (Field))
3195 (Unknown_Alignment (Styp)
3197 (Component_Bit_Offset (Field) mod
3198 (System_Storage_Unit * Alignment (Styp))) /= 0)
3204 -- For cases other than selected or indexed components we
3205 -- know we are OK, since no issues arise over alignment.
3211 -- We processed an indexed component or selected component
3212 -- reference that looked safe, so keep checking prefixes.
3214 Pref := Prefix (Pref);
3217 end Is_Possibly_Unaligned_Slice;
3219 --------------------------------
3220 -- Is_Ref_To_Bit_Packed_Array --
3221 --------------------------------
3223 function Is_Ref_To_Bit_Packed_Array (N : Node_Id) return Boolean is
3228 if Is_Entity_Name (N)
3229 and then Is_Object (Entity (N))
3230 and then Present (Renamed_Object (Entity (N)))
3232 return Is_Ref_To_Bit_Packed_Array (Renamed_Object (Entity (N)));
3235 if Nkind (N) = N_Indexed_Component
3237 Nkind (N) = N_Selected_Component
3239 if Is_Bit_Packed_Array (Etype (Prefix (N))) then
3242 Result := Is_Ref_To_Bit_Packed_Array (Prefix (N));
3245 if Result and then Nkind (N) = N_Indexed_Component then
3246 Expr := First (Expressions (N));
3247 while Present (Expr) loop
3248 Force_Evaluation (Expr);
3258 end Is_Ref_To_Bit_Packed_Array;
3260 --------------------------------
3261 -- Is_Ref_To_Bit_Packed_Slice --
3262 --------------------------------
3264 function Is_Ref_To_Bit_Packed_Slice (N : Node_Id) return Boolean is
3266 if Nkind (N) = N_Type_Conversion then
3267 return Is_Ref_To_Bit_Packed_Slice (Expression (N));
3269 elsif Is_Entity_Name (N)
3270 and then Is_Object (Entity (N))
3271 and then Present (Renamed_Object (Entity (N)))
3273 return Is_Ref_To_Bit_Packed_Slice (Renamed_Object (Entity (N)));
3275 elsif Nkind (N) = N_Slice
3276 and then Is_Bit_Packed_Array (Etype (Prefix (N)))
3280 elsif Nkind (N) = N_Indexed_Component
3282 Nkind (N) = N_Selected_Component
3284 return Is_Ref_To_Bit_Packed_Slice (Prefix (N));
3289 end Is_Ref_To_Bit_Packed_Slice;
3291 -----------------------
3292 -- Is_Renamed_Object --
3293 -----------------------
3295 function Is_Renamed_Object (N : Node_Id) return Boolean is
3296 Pnod : constant Node_Id := Parent (N);
3297 Kind : constant Node_Kind := Nkind (Pnod);
3300 if Kind = N_Object_Renaming_Declaration then
3303 elsif Kind = N_Indexed_Component
3304 or else Kind = N_Selected_Component
3306 return Is_Renamed_Object (Pnod);
3311 end Is_Renamed_Object;
3313 ----------------------------
3314 -- Is_Untagged_Derivation --
3315 ----------------------------
3317 function Is_Untagged_Derivation (T : Entity_Id) return Boolean is
3319 return (not Is_Tagged_Type (T) and then Is_Derived_Type (T))
3321 (Is_Private_Type (T) and then Present (Full_View (T))
3322 and then not Is_Tagged_Type (Full_View (T))
3323 and then Is_Derived_Type (Full_View (T))
3324 and then Etype (Full_View (T)) /= T);
3325 end Is_Untagged_Derivation;
3327 ---------------------------
3328 -- Is_Volatile_Reference --
3329 ---------------------------
3331 function Is_Volatile_Reference (N : Node_Id) return Boolean is
3333 if Nkind (N) in N_Has_Etype
3334 and then Present (Etype (N))
3335 and then Treat_As_Volatile (Etype (N))
3339 elsif Is_Entity_Name (N) then
3340 return Treat_As_Volatile (Entity (N));
3342 elsif Nkind (N) = N_Slice then
3343 return Is_Volatile_Reference (Prefix (N));
3345 elsif Nkind_In (N, N_Indexed_Component, N_Selected_Component) then
3346 if (Is_Entity_Name (Prefix (N))
3347 and then Has_Volatile_Components (Entity (Prefix (N))))
3348 or else (Present (Etype (Prefix (N)))
3349 and then Has_Volatile_Components (Etype (Prefix (N))))
3353 return Is_Volatile_Reference (Prefix (N));
3359 end Is_Volatile_Reference;
3361 --------------------
3362 -- Kill_Dead_Code --
3363 --------------------
3365 procedure Kill_Dead_Code (N : Node_Id; Warn : Boolean := False) is
3368 Remove_Warning_Messages (N);
3372 ("?this code can never be executed and has been deleted!", N);
3375 -- Recurse into block statements and bodies to process declarations
3378 if Nkind (N) = N_Block_Statement
3379 or else Nkind (N) = N_Subprogram_Body
3380 or else Nkind (N) = N_Package_Body
3382 Kill_Dead_Code (Declarations (N), False);
3383 Kill_Dead_Code (Statements (Handled_Statement_Sequence (N)));
3385 if Nkind (N) = N_Subprogram_Body then
3386 Set_Is_Eliminated (Defining_Entity (N));
3389 elsif Nkind (N) = N_Package_Declaration then
3390 Kill_Dead_Code (Visible_Declarations (Specification (N)));
3391 Kill_Dead_Code (Private_Declarations (Specification (N)));
3393 -- ??? After this point, Delete_Tree has been called on all
3394 -- declarations in Specification (N), so references to
3395 -- entities therein look suspicious.
3398 E : Entity_Id := First_Entity (Defining_Entity (N));
3400 while Present (E) loop
3401 if Ekind (E) = E_Operator then
3402 Set_Is_Eliminated (E);
3409 -- Recurse into composite statement to kill individual statements,
3410 -- in particular instantiations.
3412 elsif Nkind (N) = N_If_Statement then
3413 Kill_Dead_Code (Then_Statements (N));
3414 Kill_Dead_Code (Elsif_Parts (N));
3415 Kill_Dead_Code (Else_Statements (N));
3417 elsif Nkind (N) = N_Loop_Statement then
3418 Kill_Dead_Code (Statements (N));
3420 elsif Nkind (N) = N_Case_Statement then
3424 Alt := First (Alternatives (N));
3425 while Present (Alt) loop
3426 Kill_Dead_Code (Statements (Alt));
3431 elsif Nkind (N) = N_Case_Statement_Alternative then
3432 Kill_Dead_Code (Statements (N));
3434 -- Deal with dead instances caused by deleting instantiations
3436 elsif Nkind (N) in N_Generic_Instantiation then
3437 Remove_Dead_Instance (N);
3442 -- Case where argument is a list of nodes to be killed
3444 procedure Kill_Dead_Code (L : List_Id; Warn : Boolean := False) is
3449 if Is_Non_Empty_List (L) then
3451 while Present (N) loop
3452 Kill_Dead_Code (N, W);
3459 ------------------------
3460 -- Known_Non_Negative --
3461 ------------------------
3463 function Known_Non_Negative (Opnd : Node_Id) return Boolean is
3465 if Is_OK_Static_Expression (Opnd)
3466 and then Expr_Value (Opnd) >= 0
3472 Lo : constant Node_Id := Type_Low_Bound (Etype (Opnd));
3476 Is_OK_Static_Expression (Lo) and then Expr_Value (Lo) >= 0;
3479 end Known_Non_Negative;
3481 --------------------
3482 -- Known_Non_Null --
3483 --------------------
3485 function Known_Non_Null (N : Node_Id) return Boolean is
3487 -- Checks for case where N is an entity reference
3489 if Is_Entity_Name (N) and then Present (Entity (N)) then
3491 E : constant Entity_Id := Entity (N);
3496 -- First check if we are in decisive conditional
3498 Get_Current_Value_Condition (N, Op, Val);
3500 if Known_Null (Val) then
3501 if Op = N_Op_Eq then
3503 elsif Op = N_Op_Ne then
3508 -- If OK to do replacement, test Is_Known_Non_Null flag
3510 if OK_To_Do_Constant_Replacement (E) then
3511 return Is_Known_Non_Null (E);
3513 -- Otherwise if not safe to do replacement, then say so
3520 -- True if access attribute
3522 elsif Nkind (N) = N_Attribute_Reference
3523 and then (Attribute_Name (N) = Name_Access
3525 Attribute_Name (N) = Name_Unchecked_Access
3527 Attribute_Name (N) = Name_Unrestricted_Access)
3531 -- True if allocator
3533 elsif Nkind (N) = N_Allocator then
3536 -- For a conversion, true if expression is known non-null
3538 elsif Nkind (N) = N_Type_Conversion then
3539 return Known_Non_Null (Expression (N));
3541 -- Above are all cases where the value could be determined to be
3542 -- non-null. In all other cases, we don't know, so return False.
3553 function Known_Null (N : Node_Id) return Boolean is
3555 -- Checks for case where N is an entity reference
3557 if Is_Entity_Name (N) and then Present (Entity (N)) then
3559 E : constant Entity_Id := Entity (N);
3564 -- Constant null value is for sure null
3566 if Ekind (E) = E_Constant
3567 and then Known_Null (Constant_Value (E))
3572 -- First check if we are in decisive conditional
3574 Get_Current_Value_Condition (N, Op, Val);
3576 if Known_Null (Val) then
3577 if Op = N_Op_Eq then
3579 elsif Op = N_Op_Ne then
3584 -- If OK to do replacement, test Is_Known_Null flag
3586 if OK_To_Do_Constant_Replacement (E) then
3587 return Is_Known_Null (E);
3589 -- Otherwise if not safe to do replacement, then say so
3596 -- True if explicit reference to null
3598 elsif Nkind (N) = N_Null then
3601 -- For a conversion, true if expression is known null
3603 elsif Nkind (N) = N_Type_Conversion then
3604 return Known_Null (Expression (N));
3606 -- Above are all cases where the value could be determined to be null.
3607 -- In all other cases, we don't know, so return False.
3614 -----------------------------
3615 -- Make_CW_Equivalent_Type --
3616 -----------------------------
3618 -- Create a record type used as an equivalent of any member
3619 -- of the class which takes its size from exp.
3621 -- Generate the following code:
3623 -- type Equiv_T is record
3624 -- _parent : T (List of discriminant constraints taken from Exp);
3625 -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8);
3628 -- ??? Note that this type does not guarantee same alignment as all
3631 function Make_CW_Equivalent_Type
3633 E : Node_Id) return Entity_Id
3635 Loc : constant Source_Ptr := Sloc (E);
3636 Root_Typ : constant Entity_Id := Root_Type (T);
3637 List_Def : constant List_Id := Empty_List;
3638 Comp_List : constant List_Id := New_List;
3639 Equiv_Type : Entity_Id;
3640 Range_Type : Entity_Id;
3641 Str_Type : Entity_Id;
3642 Constr_Root : Entity_Id;
3646 if not Has_Discriminants (Root_Typ) then
3647 Constr_Root := Root_Typ;
3650 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3652 -- subtype cstr__n is T (List of discr constraints taken from Exp)
3654 Append_To (List_Def,
3655 Make_Subtype_Declaration (Loc,
3656 Defining_Identifier => Constr_Root,
3657 Subtype_Indication =>
3658 Make_Subtype_From_Expr (E, Root_Typ)));
3661 -- Generate the range subtype declaration
3663 Range_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
3665 if not Is_Interface (Root_Typ) then
3666 -- subtype rg__xx is
3667 -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit
3670 Make_Op_Subtract (Loc,
3672 Make_Attribute_Reference (Loc,
3674 OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
3675 Attribute_Name => Name_Size),
3677 Make_Attribute_Reference (Loc,
3678 Prefix => New_Reference_To (Constr_Root, Loc),
3679 Attribute_Name => Name_Object_Size));
3681 -- subtype rg__xx is
3682 -- Storage_Offset range 1 .. Expr'size / Storage_Unit
3685 Make_Attribute_Reference (Loc,
3687 OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
3688 Attribute_Name => Name_Size);
3691 Set_Paren_Count (Sizexpr, 1);
3693 Append_To (List_Def,
3694 Make_Subtype_Declaration (Loc,
3695 Defining_Identifier => Range_Type,
3696 Subtype_Indication =>
3697 Make_Subtype_Indication (Loc,
3698 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Offset), Loc),
3699 Constraint => Make_Range_Constraint (Loc,
3702 Low_Bound => Make_Integer_Literal (Loc, 1),
3704 Make_Op_Divide (Loc,
3705 Left_Opnd => Sizexpr,
3706 Right_Opnd => Make_Integer_Literal (Loc,
3707 Intval => System_Storage_Unit)))))));
3709 -- subtype str__nn is Storage_Array (rg__x);
3711 Str_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
3712 Append_To (List_Def,
3713 Make_Subtype_Declaration (Loc,
3714 Defining_Identifier => Str_Type,
3715 Subtype_Indication =>
3716 Make_Subtype_Indication (Loc,
3717 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Array), Loc),
3719 Make_Index_Or_Discriminant_Constraint (Loc,
3721 New_List (New_Reference_To (Range_Type, Loc))))));
3723 -- type Equiv_T is record
3724 -- [ _parent : Tnn; ]
3728 Equiv_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
3730 -- When the target requires front-end layout, it's necessary to allow
3731 -- the equivalent type to be frozen so that layout can occur (when the
3732 -- associated class-wide subtype is frozen, the equivalent type will
3733 -- be frozen, see freeze.adb). For other targets, Gigi wants to have
3734 -- the equivalent type marked as frozen and deals with this type itself.
3735 -- In the Gigi case this will also avoid the generation of an init
3736 -- procedure for the type.
3738 if not Frontend_Layout_On_Target then
3739 Set_Is_Frozen (Equiv_Type);
3742 Set_Ekind (Equiv_Type, E_Record_Type);
3743 Set_Parent_Subtype (Equiv_Type, Constr_Root);
3745 if not Is_Interface (Root_Typ) then
3746 Append_To (Comp_List,
3747 Make_Component_Declaration (Loc,
3748 Defining_Identifier =>
3749 Make_Defining_Identifier (Loc, Name_uParent),
3750 Component_Definition =>
3751 Make_Component_Definition (Loc,
3752 Aliased_Present => False,
3753 Subtype_Indication => New_Reference_To (Constr_Root, Loc))));
3756 Append_To (Comp_List,
3757 Make_Component_Declaration (Loc,
3758 Defining_Identifier =>
3759 Make_Defining_Identifier (Loc,
3760 Chars => New_Internal_Name ('C')),
3761 Component_Definition =>
3762 Make_Component_Definition (Loc,
3763 Aliased_Present => False,
3764 Subtype_Indication => New_Reference_To (Str_Type, Loc))));
3766 Append_To (List_Def,
3767 Make_Full_Type_Declaration (Loc,
3768 Defining_Identifier => Equiv_Type,
3770 Make_Record_Definition (Loc,
3772 Make_Component_List (Loc,
3773 Component_Items => Comp_List,
3774 Variant_Part => Empty))));
3776 -- Suppress all checks during the analysis of the expanded code
3777 -- to avoid the generation of spurious warnings under ZFP run-time.
3779 Insert_Actions (E, List_Def, Suppress => All_Checks);
3781 end Make_CW_Equivalent_Type;
3783 ------------------------
3784 -- Make_Literal_Range --
3785 ------------------------
3787 function Make_Literal_Range
3789 Literal_Typ : Entity_Id) return Node_Id
3791 Lo : constant Node_Id :=
3792 New_Copy_Tree (String_Literal_Low_Bound (Literal_Typ));
3793 Index : constant Entity_Id := Etype (Lo);
3796 Length_Expr : constant Node_Id :=
3797 Make_Op_Subtract (Loc,
3799 Make_Integer_Literal (Loc,
3800 Intval => String_Literal_Length (Literal_Typ)),
3802 Make_Integer_Literal (Loc, 1));
3805 Set_Analyzed (Lo, False);
3807 if Is_Integer_Type (Index) then
3810 Left_Opnd => New_Copy_Tree (Lo),
3811 Right_Opnd => Length_Expr);
3814 Make_Attribute_Reference (Loc,
3815 Attribute_Name => Name_Val,
3816 Prefix => New_Occurrence_Of (Index, Loc),
3817 Expressions => New_List (
3820 Make_Attribute_Reference (Loc,
3821 Attribute_Name => Name_Pos,
3822 Prefix => New_Occurrence_Of (Index, Loc),
3823 Expressions => New_List (New_Copy_Tree (Lo))),
3824 Right_Opnd => Length_Expr)));
3831 end Make_Literal_Range;
3833 --------------------------
3834 -- Make_Non_Empty_Check --
3835 --------------------------
3837 function Make_Non_Empty_Check
3839 N : Node_Id) return Node_Id
3845 Make_Attribute_Reference (Loc,
3846 Attribute_Name => Name_Length,
3847 Prefix => Duplicate_Subexpr_No_Checks (N, Name_Req => True)),
3849 Make_Integer_Literal (Loc, 0));
3850 end Make_Non_Empty_Check;
3852 ----------------------------
3853 -- Make_Subtype_From_Expr --
3854 ----------------------------
3856 -- 1. If Expr is an unconstrained array expression, creates
3857 -- Unc_Type(Expr'first(1)..Expr'last(1),..., Expr'first(n)..Expr'last(n))
3859 -- 2. If Expr is a unconstrained discriminated type expression, creates
3860 -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n)
3862 -- 3. If Expr is class-wide, creates an implicit class wide subtype
3864 function Make_Subtype_From_Expr
3866 Unc_Typ : Entity_Id) return Node_Id
3868 Loc : constant Source_Ptr := Sloc (E);
3869 List_Constr : constant List_Id := New_List;
3872 Full_Subtyp : Entity_Id;
3873 Priv_Subtyp : Entity_Id;
3878 if Is_Private_Type (Unc_Typ)
3879 and then Has_Unknown_Discriminants (Unc_Typ)
3881 -- Prepare the subtype completion, Go to base type to
3882 -- find underlying type, because the type may be a generic
3883 -- actual or an explicit subtype.
3885 Utyp := Underlying_Type (Base_Type (Unc_Typ));
3886 Full_Subtyp := Make_Defining_Identifier (Loc,
3887 New_Internal_Name ('C'));
3889 Unchecked_Convert_To
3890 (Utyp, Duplicate_Subexpr_No_Checks (E));
3891 Set_Parent (Full_Exp, Parent (E));
3894 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
3897 Make_Subtype_Declaration (Loc,
3898 Defining_Identifier => Full_Subtyp,
3899 Subtype_Indication => Make_Subtype_From_Expr (Full_Exp, Utyp)));
3901 -- Define the dummy private subtype
3903 Set_Ekind (Priv_Subtyp, Subtype_Kind (Ekind (Unc_Typ)));
3904 Set_Etype (Priv_Subtyp, Base_Type (Unc_Typ));
3905 Set_Scope (Priv_Subtyp, Full_Subtyp);
3906 Set_Is_Constrained (Priv_Subtyp);
3907 Set_Is_Tagged_Type (Priv_Subtyp, Is_Tagged_Type (Unc_Typ));
3908 Set_Is_Itype (Priv_Subtyp);
3909 Set_Associated_Node_For_Itype (Priv_Subtyp, E);
3911 if Is_Tagged_Type (Priv_Subtyp) then
3913 (Base_Type (Priv_Subtyp), Class_Wide_Type (Unc_Typ));
3914 Set_Primitive_Operations (Priv_Subtyp,
3915 Primitive_Operations (Unc_Typ));
3918 Set_Full_View (Priv_Subtyp, Full_Subtyp);
3920 return New_Reference_To (Priv_Subtyp, Loc);
3922 elsif Is_Array_Type (Unc_Typ) then
3923 for J in 1 .. Number_Dimensions (Unc_Typ) loop
3924 Append_To (List_Constr,
3927 Make_Attribute_Reference (Loc,
3928 Prefix => Duplicate_Subexpr_No_Checks (E),
3929 Attribute_Name => Name_First,
3930 Expressions => New_List (
3931 Make_Integer_Literal (Loc, J))),
3934 Make_Attribute_Reference (Loc,
3935 Prefix => Duplicate_Subexpr_No_Checks (E),
3936 Attribute_Name => Name_Last,
3937 Expressions => New_List (
3938 Make_Integer_Literal (Loc, J)))));
3941 elsif Is_Class_Wide_Type (Unc_Typ) then
3943 CW_Subtype : Entity_Id;
3944 EQ_Typ : Entity_Id := Empty;
3947 -- A class-wide equivalent type is not needed when VM_Target
3948 -- because the VM back-ends handle the class-wide object
3949 -- initialization itself (and doesn't need or want the
3950 -- additional intermediate type to handle the assignment).
3952 if Expander_Active and then Tagged_Type_Expansion then
3953 EQ_Typ := Make_CW_Equivalent_Type (Unc_Typ, E);
3956 CW_Subtype := New_Class_Wide_Subtype (Unc_Typ, E);
3957 Set_Equivalent_Type (CW_Subtype, EQ_Typ);
3959 if Present (EQ_Typ) then
3960 Set_Is_Class_Wide_Equivalent_Type (EQ_Typ);
3963 Set_Cloned_Subtype (CW_Subtype, Base_Type (Unc_Typ));
3965 return New_Occurrence_Of (CW_Subtype, Loc);
3968 -- Indefinite record type with discriminants
3971 D := First_Discriminant (Unc_Typ);
3972 while Present (D) loop
3973 Append_To (List_Constr,
3974 Make_Selected_Component (Loc,
3975 Prefix => Duplicate_Subexpr_No_Checks (E),
3976 Selector_Name => New_Reference_To (D, Loc)));
3978 Next_Discriminant (D);
3983 Make_Subtype_Indication (Loc,
3984 Subtype_Mark => New_Reference_To (Unc_Typ, Loc),
3986 Make_Index_Or_Discriminant_Constraint (Loc,
3987 Constraints => List_Constr));
3988 end Make_Subtype_From_Expr;
3990 -----------------------------
3991 -- May_Generate_Large_Temp --
3992 -----------------------------
3994 -- At the current time, the only types that we return False for (i.e.
3995 -- where we decide we know they cannot generate large temps) are ones
3996 -- where we know the size is 256 bits or less at compile time, and we
3997 -- are still not doing a thorough job on arrays and records ???
3999 function May_Generate_Large_Temp (Typ : Entity_Id) return Boolean is
4001 if not Size_Known_At_Compile_Time (Typ) then
4004 elsif Esize (Typ) /= 0 and then Esize (Typ) <= 256 then
4007 elsif Is_Array_Type (Typ)
4008 and then Present (Packed_Array_Type (Typ))
4010 return May_Generate_Large_Temp (Packed_Array_Type (Typ));
4012 -- We could do more here to find other small types ???
4017 end May_Generate_Large_Temp;
4019 ----------------------------
4020 -- New_Class_Wide_Subtype --
4021 ----------------------------
4023 function New_Class_Wide_Subtype
4024 (CW_Typ : Entity_Id;
4025 N : Node_Id) return Entity_Id
4027 Res : constant Entity_Id := Create_Itype (E_Void, N);
4028 Res_Name : constant Name_Id := Chars (Res);
4029 Res_Scope : constant Entity_Id := Scope (Res);
4032 Copy_Node (CW_Typ, Res);
4033 Set_Comes_From_Source (Res, False);
4034 Set_Sloc (Res, Sloc (N));
4036 Set_Associated_Node_For_Itype (Res, N);
4037 Set_Is_Public (Res, False); -- By default, may be changed below.
4038 Set_Public_Status (Res);
4039 Set_Chars (Res, Res_Name);
4040 Set_Scope (Res, Res_Scope);
4041 Set_Ekind (Res, E_Class_Wide_Subtype);
4042 Set_Next_Entity (Res, Empty);
4043 Set_Etype (Res, Base_Type (CW_Typ));
4045 -- For targets where front-end layout is required, reset the Is_Frozen
4046 -- status of the subtype to False (it can be implicitly set to true
4047 -- from the copy of the class-wide type). For other targets, Gigi
4048 -- doesn't want the class-wide subtype to go through the freezing
4049 -- process (though it's unclear why that causes problems and it would
4050 -- be nice to allow freezing to occur normally for all targets ???).
4052 if Frontend_Layout_On_Target then
4053 Set_Is_Frozen (Res, False);
4056 Set_Freeze_Node (Res, Empty);
4058 end New_Class_Wide_Subtype;
4060 --------------------------------
4061 -- Non_Limited_Designated_Type --
4062 ---------------------------------
4064 function Non_Limited_Designated_Type (T : Entity_Id) return Entity_Id is
4065 Desig : constant Entity_Id := Designated_Type (T);
4067 if Ekind (Desig) = E_Incomplete_Type
4068 and then Present (Non_Limited_View (Desig))
4070 return Non_Limited_View (Desig);
4074 end Non_Limited_Designated_Type;
4076 -----------------------------------
4077 -- OK_To_Do_Constant_Replacement --
4078 -----------------------------------
4080 function OK_To_Do_Constant_Replacement (E : Entity_Id) return Boolean is
4081 ES : constant Entity_Id := Scope (E);
4085 -- Do not replace statically allocated objects, because they may be
4086 -- modified outside the current scope.
4088 if Is_Statically_Allocated (E) then
4091 -- Do not replace aliased or volatile objects, since we don't know what
4092 -- else might change the value.
4094 elsif Is_Aliased (E) or else Treat_As_Volatile (E) then
4097 -- Debug flag -gnatdM disconnects this optimization
4099 elsif Debug_Flag_MM then
4102 -- Otherwise check scopes
4105 CS := Current_Scope;
4108 -- If we are in right scope, replacement is safe
4113 -- Packages do not affect the determination of safety
4115 elsif Ekind (CS) = E_Package then
4116 exit when CS = Standard_Standard;
4119 -- Blocks do not affect the determination of safety
4121 elsif Ekind (CS) = E_Block then
4124 -- Loops do not affect the determination of safety. Note that we
4125 -- kill all current values on entry to a loop, so we are just
4126 -- talking about processing within a loop here.
4128 elsif Ekind (CS) = E_Loop then
4131 -- Otherwise, the reference is dubious, and we cannot be sure that
4132 -- it is safe to do the replacement.
4141 end OK_To_Do_Constant_Replacement;
4143 ------------------------------------
4144 -- Possible_Bit_Aligned_Component --
4145 ------------------------------------
4147 function Possible_Bit_Aligned_Component (N : Node_Id) return Boolean is
4151 -- Case of indexed component
4153 when N_Indexed_Component =>
4155 P : constant Node_Id := Prefix (N);
4156 Ptyp : constant Entity_Id := Etype (P);
4159 -- If we know the component size and it is less than 64, then
4160 -- we are definitely OK. The back end always does assignment of
4161 -- misaligned small objects correctly.
4163 if Known_Static_Component_Size (Ptyp)
4164 and then Component_Size (Ptyp) <= 64
4168 -- Otherwise, we need to test the prefix, to see if we are
4169 -- indexing from a possibly unaligned component.
4172 return Possible_Bit_Aligned_Component (P);
4176 -- Case of selected component
4178 when N_Selected_Component =>
4180 P : constant Node_Id := Prefix (N);
4181 Comp : constant Entity_Id := Entity (Selector_Name (N));
4184 -- If there is no component clause, then we are in the clear
4185 -- since the back end will never misalign a large component
4186 -- unless it is forced to do so. In the clear means we need
4187 -- only the recursive test on the prefix.
4189 if Component_May_Be_Bit_Aligned (Comp) then
4192 return Possible_Bit_Aligned_Component (P);
4196 -- For a slice, test the prefix, if that is possibly misaligned,
4197 -- then for sure the slice is!
4200 return Possible_Bit_Aligned_Component (Prefix (N));
4202 -- If we have none of the above, it means that we have fallen off the
4203 -- top testing prefixes recursively, and we now have a stand alone
4204 -- object, where we don't have a problem.
4210 end Possible_Bit_Aligned_Component;
4212 -------------------------
4213 -- Remove_Side_Effects --
4214 -------------------------
4216 procedure Remove_Side_Effects
4218 Name_Req : Boolean := False;
4219 Variable_Ref : Boolean := False)
4221 Loc : constant Source_Ptr := Sloc (Exp);
4222 Exp_Type : constant Entity_Id := Etype (Exp);
4223 Svg_Suppress : constant Suppress_Array := Scope_Suppress;
4225 Ref_Type : Entity_Id;
4227 Ptr_Typ_Decl : Node_Id;
4231 function Side_Effect_Free (N : Node_Id) return Boolean;
4232 -- Determines if the tree N represents an expression that is known not
4233 -- to have side effects, and for which no processing is required.
4235 function Side_Effect_Free (L : List_Id) return Boolean;
4236 -- Determines if all elements of the list L are side effect free
4238 function Safe_Prefixed_Reference (N : Node_Id) return Boolean;
4239 -- The argument N is a construct where the Prefix is dereferenced if it
4240 -- is an access type and the result is a variable. The call returns True
4241 -- if the construct is side effect free (not considering side effects in
4242 -- other than the prefix which are to be tested by the caller).
4244 function Within_In_Parameter (N : Node_Id) return Boolean;
4245 -- Determines if N is a subcomponent of a composite in-parameter. If so,
4246 -- N is not side-effect free when the actual is global and modifiable
4247 -- indirectly from within a subprogram, because it may be passed by
4248 -- reference. The front-end must be conservative here and assume that
4249 -- this may happen with any array or record type. On the other hand, we
4250 -- cannot create temporaries for all expressions for which this
4251 -- condition is true, for various reasons that might require clearing up
4252 -- ??? For example, discriminant references that appear out of place, or
4253 -- spurious type errors with class-wide expressions. As a result, we
4254 -- limit the transformation to loop bounds, which is so far the only
4255 -- case that requires it.
4257 -----------------------------
4258 -- Safe_Prefixed_Reference --
4259 -----------------------------
4261 function Safe_Prefixed_Reference (N : Node_Id) return Boolean is
4263 -- If prefix is not side effect free, definitely not safe
4265 if not Side_Effect_Free (Prefix (N)) then
4268 -- If the prefix is of an access type that is not access-to-constant,
4269 -- then this construct is a variable reference, which means it is to
4270 -- be considered to have side effects if Variable_Ref is set True
4271 -- Exception is an access to an entity that is a constant or an
4272 -- in-parameter which does not come from source, and is the result
4273 -- of a previous removal of side-effects.
4275 elsif Is_Access_Type (Etype (Prefix (N)))
4276 and then not Is_Access_Constant (Etype (Prefix (N)))
4277 and then Variable_Ref
4279 if not Is_Entity_Name (Prefix (N)) then
4282 return Ekind (Entity (Prefix (N))) = E_Constant
4283 or else Ekind (Entity (Prefix (N))) = E_In_Parameter;
4286 -- The following test is the simplest way of solving a complex
4287 -- problem uncovered by BB08-010: Side effect on loop bound that
4288 -- is a subcomponent of a global variable:
4289 -- If a loop bound is a subcomponent of a global variable, a
4290 -- modification of that variable within the loop may incorrectly
4291 -- affect the execution of the loop.
4294 (Nkind (Parent (Parent (N))) /= N_Loop_Parameter_Specification
4295 or else not Within_In_Parameter (Prefix (N)))
4299 -- All other cases are side effect free
4304 end Safe_Prefixed_Reference;
4306 ----------------------
4307 -- Side_Effect_Free --
4308 ----------------------
4310 function Side_Effect_Free (N : Node_Id) return Boolean is
4312 -- Note on checks that could raise Constraint_Error. Strictly, if
4313 -- we take advantage of 11.6, these checks do not count as side
4314 -- effects. However, we would just as soon consider that they are
4315 -- side effects, since the backend CSE does not work very well on
4316 -- expressions which can raise Constraint_Error. On the other
4317 -- hand, if we do not consider them to be side effect free, then
4318 -- we get some awkward expansions in -gnato mode, resulting in
4319 -- code insertions at a point where we do not have a clear model
4320 -- for performing the insertions.
4322 -- Special handling for entity names
4324 if Is_Entity_Name (N) then
4326 -- If the entity is a constant, it is definitely side effect
4327 -- free. Note that the test of Is_Variable (N) below might
4328 -- be expected to catch this case, but it does not, because
4329 -- this test goes to the original tree, and we may have
4330 -- already rewritten a variable node with a constant as
4331 -- a result of an earlier Force_Evaluation call.
4333 if Ekind (Entity (N)) = E_Constant
4334 or else Ekind (Entity (N)) = E_In_Parameter
4338 -- Functions are not side effect free
4340 elsif Ekind (Entity (N)) = E_Function then
4343 -- Variables are considered to be a side effect if Variable_Ref
4344 -- is set or if we have a volatile reference and Name_Req is off.
4345 -- If Name_Req is True then we can't help returning a name which
4346 -- effectively allows multiple references in any case.
4348 elsif Is_Variable (N) then
4349 return not Variable_Ref
4350 and then (not Is_Volatile_Reference (N) or else Name_Req);
4352 -- Any other entity (e.g. a subtype name) is definitely side
4359 -- A value known at compile time is always side effect free
4361 elsif Compile_Time_Known_Value (N) then
4364 -- A variable renaming is not side-effect free, because the
4365 -- renaming will function like a macro in the front-end in
4366 -- some cases, and an assignment can modify the component
4367 -- designated by N, so we need to create a temporary for it.
4369 elsif Is_Entity_Name (Original_Node (N))
4370 and then Is_Renaming_Of_Object (Entity (Original_Node (N)))
4371 and then Ekind (Entity (Original_Node (N))) /= E_Constant
4376 -- For other than entity names and compile time known values,
4377 -- check the node kind for special processing.
4381 -- An attribute reference is side effect free if its expressions
4382 -- are side effect free and its prefix is side effect free or
4383 -- is an entity reference.
4385 -- Is this right? what about x'first where x is a variable???
4387 when N_Attribute_Reference =>
4388 return Side_Effect_Free (Expressions (N))
4389 and then Attribute_Name (N) /= Name_Input
4390 and then (Is_Entity_Name (Prefix (N))
4391 or else Side_Effect_Free (Prefix (N)));
4393 -- A binary operator is side effect free if and both operands
4394 -- are side effect free. For this purpose binary operators
4395 -- include membership tests and short circuit forms
4397 when N_Binary_Op | N_Membership_Test | N_Short_Circuit =>
4398 return Side_Effect_Free (Left_Opnd (N))
4400 Side_Effect_Free (Right_Opnd (N));
4402 -- An explicit dereference is side effect free only if it is
4403 -- a side effect free prefixed reference.
4405 when N_Explicit_Dereference =>
4406 return Safe_Prefixed_Reference (N);
4408 -- A call to _rep_to_pos is side effect free, since we generate
4409 -- this pure function call ourselves. Moreover it is critically
4410 -- important to make this exception, since otherwise we can
4411 -- have discriminants in array components which don't look
4412 -- side effect free in the case of an array whose index type
4413 -- is an enumeration type with an enumeration rep clause.
4415 -- All other function calls are not side effect free
4417 when N_Function_Call =>
4418 return Nkind (Name (N)) = N_Identifier
4419 and then Is_TSS (Name (N), TSS_Rep_To_Pos)
4421 Side_Effect_Free (First (Parameter_Associations (N)));
4423 -- An indexed component is side effect free if it is a side
4424 -- effect free prefixed reference and all the indexing
4425 -- expressions are side effect free.
4427 when N_Indexed_Component =>
4428 return Side_Effect_Free (Expressions (N))
4429 and then Safe_Prefixed_Reference (N);
4431 -- A type qualification is side effect free if the expression
4432 -- is side effect free.
4434 when N_Qualified_Expression =>
4435 return Side_Effect_Free (Expression (N));
4437 -- A selected component is side effect free only if it is a
4438 -- side effect free prefixed reference. If it designates a
4439 -- component with a rep. clause it must be treated has having
4440 -- a potential side effect, because it may be modified through
4441 -- a renaming, and a subsequent use of the renaming as a macro
4442 -- will yield the wrong value. This complex interaction between
4443 -- renaming and removing side effects is a reminder that the
4444 -- latter has become a headache to maintain, and that it should
4445 -- be removed in favor of the gcc mechanism to capture values ???
4447 when N_Selected_Component =>
4448 if Nkind (Parent (N)) = N_Explicit_Dereference
4449 and then Has_Non_Standard_Rep (Designated_Type (Etype (N)))
4453 return Safe_Prefixed_Reference (N);
4456 -- A range is side effect free if the bounds are side effect free
4459 return Side_Effect_Free (Low_Bound (N))
4460 and then Side_Effect_Free (High_Bound (N));
4462 -- A slice is side effect free if it is a side effect free
4463 -- prefixed reference and the bounds are side effect free.
4466 return Side_Effect_Free (Discrete_Range (N))
4467 and then Safe_Prefixed_Reference (N);
4469 -- A type conversion is side effect free if the expression to be
4470 -- converted is side effect free.
4472 when N_Type_Conversion =>
4473 return Side_Effect_Free (Expression (N));
4475 -- A unary operator is side effect free if the operand
4476 -- is side effect free.
4479 return Side_Effect_Free (Right_Opnd (N));
4481 -- An unchecked type conversion is side effect free only if it
4482 -- is safe and its argument is side effect free.
4484 when N_Unchecked_Type_Conversion =>
4485 return Safe_Unchecked_Type_Conversion (N)
4486 and then Side_Effect_Free (Expression (N));
4488 -- An unchecked expression is side effect free if its expression
4489 -- is side effect free.
4491 when N_Unchecked_Expression =>
4492 return Side_Effect_Free (Expression (N));
4494 -- A literal is side effect free
4496 when N_Character_Literal |
4502 -- We consider that anything else has side effects. This is a bit
4503 -- crude, but we are pretty close for most common cases, and we
4504 -- are certainly correct (i.e. we never return True when the
4505 -- answer should be False).
4510 end Side_Effect_Free;
4512 -- A list is side effect free if all elements of the list are
4513 -- side effect free.
4515 function Side_Effect_Free (L : List_Id) return Boolean is
4519 if L = No_List or else L = Error_List then
4524 while Present (N) loop
4525 if not Side_Effect_Free (N) then
4534 end Side_Effect_Free;
4536 -------------------------
4537 -- Within_In_Parameter --
4538 -------------------------
4540 function Within_In_Parameter (N : Node_Id) return Boolean is
4542 if not Comes_From_Source (N) then
4545 elsif Is_Entity_Name (N) then
4546 return Ekind (Entity (N)) = E_In_Parameter;
4548 elsif Nkind (N) = N_Indexed_Component
4549 or else Nkind (N) = N_Selected_Component
4551 return Within_In_Parameter (Prefix (N));
4556 end Within_In_Parameter;
4558 -- Start of processing for Remove_Side_Effects
4561 -- If we are side effect free already or expansion is disabled,
4562 -- there is nothing to do.
4564 if Side_Effect_Free (Exp) or else not Expander_Active then
4568 -- All this must not have any checks
4570 Scope_Suppress := (others => True);
4572 -- If it is a scalar type and we need to capture the value, just make
4573 -- a copy. Likewise for a function call, an attribute reference or an
4574 -- operator. And if we have a volatile reference and Name_Req is not
4575 -- set (see comments above for Side_Effect_Free).
4577 if Is_Elementary_Type (Exp_Type)
4578 and then (Variable_Ref
4579 or else Nkind (Exp) = N_Function_Call
4580 or else Nkind (Exp) = N_Attribute_Reference
4581 or else Nkind (Exp) in N_Op
4582 or else (not Name_Req and then Is_Volatile_Reference (Exp)))
4584 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4585 Set_Etype (Def_Id, Exp_Type);
4586 Res := New_Reference_To (Def_Id, Loc);
4589 Make_Object_Declaration (Loc,
4590 Defining_Identifier => Def_Id,
4591 Object_Definition => New_Reference_To (Exp_Type, Loc),
4592 Constant_Present => True,
4593 Expression => Relocate_Node (Exp));
4595 Set_Assignment_OK (E);
4596 Insert_Action (Exp, E);
4597 Set_Related_Expression (Def_Id, Exp);
4599 -- If the expression has the form v.all then we can just capture
4600 -- the pointer, and then do an explicit dereference on the result.
4602 elsif Nkind (Exp) = N_Explicit_Dereference then
4604 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4606 Make_Explicit_Dereference (Loc, New_Reference_To (Def_Id, Loc));
4609 Make_Object_Declaration (Loc,
4610 Defining_Identifier => Def_Id,
4611 Object_Definition =>
4612 New_Reference_To (Etype (Prefix (Exp)), Loc),
4613 Constant_Present => True,
4614 Expression => Relocate_Node (Prefix (Exp))));
4615 Set_Related_Expression (Def_Id, Exp);
4617 -- Similar processing for an unchecked conversion of an expression
4618 -- of the form v.all, where we want the same kind of treatment.
4620 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
4621 and then Nkind (Expression (Exp)) = N_Explicit_Dereference
4623 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
4624 Scope_Suppress := Svg_Suppress;
4627 -- If this is a type conversion, leave the type conversion and remove
4628 -- the side effects in the expression. This is important in several
4629 -- circumstances: for change of representations, and also when this is
4630 -- a view conversion to a smaller object, where gigi can end up creating
4631 -- its own temporary of the wrong size.
4633 elsif Nkind (Exp) = N_Type_Conversion then
4634 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
4635 Scope_Suppress := Svg_Suppress;
4638 -- If this is an unchecked conversion that Gigi can't handle, make
4639 -- a copy or a use a renaming to capture the value.
4641 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
4642 and then not Safe_Unchecked_Type_Conversion (Exp)
4644 if CW_Or_Has_Controlled_Part (Exp_Type) then
4646 -- Use a renaming to capture the expression, rather than create
4647 -- a controlled temporary.
4649 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4650 Res := New_Reference_To (Def_Id, Loc);
4653 Make_Object_Renaming_Declaration (Loc,
4654 Defining_Identifier => Def_Id,
4655 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
4656 Name => Relocate_Node (Exp)));
4657 Set_Related_Expression (Def_Id, Exp);
4660 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4661 Set_Etype (Def_Id, Exp_Type);
4662 Res := New_Reference_To (Def_Id, Loc);
4665 Make_Object_Declaration (Loc,
4666 Defining_Identifier => Def_Id,
4667 Object_Definition => New_Reference_To (Exp_Type, Loc),
4668 Constant_Present => not Is_Variable (Exp),
4669 Expression => Relocate_Node (Exp));
4671 Set_Assignment_OK (E);
4672 Insert_Action (Exp, E);
4673 Set_Related_Expression (Def_Id, Exp);
4676 -- For expressions that denote objects, we can use a renaming scheme.
4677 -- We skip using this if we have a volatile reference and we do not
4678 -- have Name_Req set true (see comments above for Side_Effect_Free).
4680 elsif Is_Object_Reference (Exp)
4681 and then Nkind (Exp) /= N_Function_Call
4682 and then (Name_Req or else not Is_Volatile_Reference (Exp))
4684 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4686 if Nkind (Exp) = N_Selected_Component
4687 and then Nkind (Prefix (Exp)) = N_Function_Call
4688 and then Is_Array_Type (Exp_Type)
4690 -- Avoid generating a variable-sized temporary, by generating
4691 -- the renaming declaration just for the function call. The
4692 -- transformation could be refined to apply only when the array
4693 -- component is constrained by a discriminant???
4696 Make_Selected_Component (Loc,
4697 Prefix => New_Occurrence_Of (Def_Id, Loc),
4698 Selector_Name => Selector_Name (Exp));
4701 Make_Object_Renaming_Declaration (Loc,
4702 Defining_Identifier => Def_Id,
4704 New_Reference_To (Base_Type (Etype (Prefix (Exp))), Loc),
4705 Name => Relocate_Node (Prefix (Exp))));
4708 Res := New_Reference_To (Def_Id, Loc);
4711 Make_Object_Renaming_Declaration (Loc,
4712 Defining_Identifier => Def_Id,
4713 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
4714 Name => Relocate_Node (Exp)));
4717 Set_Related_Expression (Def_Id, Exp);
4719 -- If this is a packed reference, or a selected component with a
4720 -- non-standard representation, a reference to the temporary will
4721 -- be replaced by a copy of the original expression (see
4722 -- Exp_Ch2.Expand_Renaming). Otherwise the temporary must be
4723 -- elaborated by gigi, and is of course not to be replaced in-line
4724 -- by the expression it renames, which would defeat the purpose of
4725 -- removing the side-effect.
4727 if (Nkind (Exp) = N_Selected_Component
4728 or else Nkind (Exp) = N_Indexed_Component)
4729 and then Has_Non_Standard_Rep (Etype (Prefix (Exp)))
4733 Set_Is_Renaming_Of_Object (Def_Id, False);
4736 -- Otherwise we generate a reference to the value
4739 -- Special processing for function calls that return a task. We need
4740 -- to build a declaration that will enable build-in-place expansion
4743 -- This is relevant only in Ada 2005 mode. In Ada 95 programs we have
4744 -- to accommodate functions returning limited objects by reference.
4746 if Nkind (Exp) = N_Function_Call
4747 and then Is_Task_Type (Etype (Exp))
4748 and then Ada_Version >= Ada_05
4751 Obj : constant Entity_Id :=
4752 Make_Defining_Identifier (Loc,
4753 Chars => New_Internal_Name ('F'));
4758 Make_Object_Declaration (Loc,
4759 Defining_Identifier => Obj,
4760 Object_Definition => New_Occurrence_Of (Exp_Type, Loc),
4761 Expression => Relocate_Node (Exp));
4762 Insert_Action (Exp, Decl);
4763 Set_Etype (Obj, Exp_Type);
4764 Set_Related_Expression (Obj, Exp);
4765 Rewrite (Exp, New_Occurrence_Of (Obj, Loc));
4770 Ref_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4773 Make_Full_Type_Declaration (Loc,
4774 Defining_Identifier => Ref_Type,
4776 Make_Access_To_Object_Definition (Loc,
4777 All_Present => True,
4778 Subtype_Indication =>
4779 New_Reference_To (Exp_Type, Loc)));
4782 Insert_Action (Exp, Ptr_Typ_Decl);
4784 Def_Id := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
4785 Set_Etype (Def_Id, Exp_Type);
4788 Make_Explicit_Dereference (Loc,
4789 Prefix => New_Reference_To (Def_Id, Loc));
4791 if Nkind (E) = N_Explicit_Dereference then
4792 New_Exp := Relocate_Node (Prefix (E));
4794 E := Relocate_Node (E);
4795 New_Exp := Make_Reference (Loc, E);
4798 if Is_Delayed_Aggregate (E) then
4800 -- The expansion of nested aggregates is delayed until the
4801 -- enclosing aggregate is expanded. As aggregates are often
4802 -- qualified, the predicate applies to qualified expressions
4803 -- as well, indicating that the enclosing aggregate has not
4804 -- been expanded yet. At this point the aggregate is part of
4805 -- a stand-alone declaration, and must be fully expanded.
4807 if Nkind (E) = N_Qualified_Expression then
4808 Set_Expansion_Delayed (Expression (E), False);
4809 Set_Analyzed (Expression (E), False);
4811 Set_Expansion_Delayed (E, False);
4814 Set_Analyzed (E, False);
4818 Make_Object_Declaration (Loc,
4819 Defining_Identifier => Def_Id,
4820 Object_Definition => New_Reference_To (Ref_Type, Loc),
4821 Expression => New_Exp));
4822 Set_Related_Expression (Def_Id, Exp);
4825 -- Preserve the Assignment_OK flag in all copies, since at least
4826 -- one copy may be used in a context where this flag must be set
4827 -- (otherwise why would the flag be set in the first place).
4829 Set_Assignment_OK (Res, Assignment_OK (Exp));
4831 -- Finally rewrite the original expression and we are done
4834 Analyze_And_Resolve (Exp, Exp_Type);
4835 Scope_Suppress := Svg_Suppress;
4836 end Remove_Side_Effects;
4838 ---------------------------
4839 -- Represented_As_Scalar --
4840 ---------------------------
4842 function Represented_As_Scalar (T : Entity_Id) return Boolean is
4843 UT : constant Entity_Id := Underlying_Type (T);
4845 return Is_Scalar_Type (UT)
4846 or else (Is_Bit_Packed_Array (UT)
4847 and then Is_Scalar_Type (Packed_Array_Type (UT)));
4848 end Represented_As_Scalar;
4850 ------------------------------------
4851 -- Safe_Unchecked_Type_Conversion --
4852 ------------------------------------
4854 -- Note: this function knows quite a bit about the exact requirements
4855 -- of Gigi with respect to unchecked type conversions, and its code
4856 -- must be coordinated with any changes in Gigi in this area.
4858 -- The above requirements should be documented in Sinfo ???
4860 function Safe_Unchecked_Type_Conversion (Exp : Node_Id) return Boolean is
4865 Pexp : constant Node_Id := Parent (Exp);
4868 -- If the expression is the RHS of an assignment or object declaration
4869 -- we are always OK because there will always be a target.
4871 -- Object renaming declarations, (generated for view conversions of
4872 -- actuals in inlined calls), like object declarations, provide an
4873 -- explicit type, and are safe as well.
4875 if (Nkind (Pexp) = N_Assignment_Statement
4876 and then Expression (Pexp) = Exp)
4877 or else Nkind (Pexp) = N_Object_Declaration
4878 or else Nkind (Pexp) = N_Object_Renaming_Declaration
4882 -- If the expression is the prefix of an N_Selected_Component
4883 -- we should also be OK because GCC knows to look inside the
4884 -- conversion except if the type is discriminated. We assume
4885 -- that we are OK anyway if the type is not set yet or if it is
4886 -- controlled since we can't afford to introduce a temporary in
4889 elsif Nkind (Pexp) = N_Selected_Component
4890 and then Prefix (Pexp) = Exp
4892 if No (Etype (Pexp)) then
4896 not Has_Discriminants (Etype (Pexp))
4897 or else Is_Constrained (Etype (Pexp));
4901 -- Set the output type, this comes from Etype if it is set, otherwise
4902 -- we take it from the subtype mark, which we assume was already
4905 if Present (Etype (Exp)) then
4906 Otyp := Etype (Exp);
4908 Otyp := Entity (Subtype_Mark (Exp));
4911 -- The input type always comes from the expression, and we assume
4912 -- this is indeed always analyzed, so we can simply get the Etype.
4914 Ityp := Etype (Expression (Exp));
4916 -- Initialize alignments to unknown so far
4921 -- Replace a concurrent type by its corresponding record type
4922 -- and each type by its underlying type and do the tests on those.
4923 -- The original type may be a private type whose completion is a
4924 -- concurrent type, so find the underlying type first.
4926 if Present (Underlying_Type (Otyp)) then
4927 Otyp := Underlying_Type (Otyp);
4930 if Present (Underlying_Type (Ityp)) then
4931 Ityp := Underlying_Type (Ityp);
4934 if Is_Concurrent_Type (Otyp) then
4935 Otyp := Corresponding_Record_Type (Otyp);
4938 if Is_Concurrent_Type (Ityp) then
4939 Ityp := Corresponding_Record_Type (Ityp);
4942 -- If the base types are the same, we know there is no problem since
4943 -- this conversion will be a noop.
4945 if Implementation_Base_Type (Otyp) = Implementation_Base_Type (Ityp) then
4948 -- Same if this is an upwards conversion of an untagged type, and there
4949 -- are no constraints involved (could be more general???)
4951 elsif Etype (Ityp) = Otyp
4952 and then not Is_Tagged_Type (Ityp)
4953 and then not Has_Discriminants (Ityp)
4954 and then No (First_Rep_Item (Base_Type (Ityp)))
4958 -- If the expression has an access type (object or subprogram) we
4959 -- assume that the conversion is safe, because the size of the target
4960 -- is safe, even if it is a record (which might be treated as having
4961 -- unknown size at this point).
4963 elsif Is_Access_Type (Ityp) then
4966 -- If the size of output type is known at compile time, there is
4967 -- never a problem. Note that unconstrained records are considered
4968 -- to be of known size, but we can't consider them that way here,
4969 -- because we are talking about the actual size of the object.
4971 -- We also make sure that in addition to the size being known, we do
4972 -- not have a case which might generate an embarrassingly large temp
4973 -- in stack checking mode.
4975 elsif Size_Known_At_Compile_Time (Otyp)
4977 (not Stack_Checking_Enabled
4978 or else not May_Generate_Large_Temp (Otyp))
4979 and then not (Is_Record_Type (Otyp) and then not Is_Constrained (Otyp))
4983 -- If either type is tagged, then we know the alignment is OK so
4984 -- Gigi will be able to use pointer punning.
4986 elsif Is_Tagged_Type (Otyp) or else Is_Tagged_Type (Ityp) then
4989 -- If either type is a limited record type, we cannot do a copy, so
4990 -- say safe since there's nothing else we can do.
4992 elsif Is_Limited_Record (Otyp) or else Is_Limited_Record (Ityp) then
4995 -- Conversions to and from packed array types are always ignored and
4998 elsif Is_Packed_Array_Type (Otyp)
4999 or else Is_Packed_Array_Type (Ityp)
5004 -- The only other cases known to be safe is if the input type's
5005 -- alignment is known to be at least the maximum alignment for the
5006 -- target or if both alignments are known and the output type's
5007 -- alignment is no stricter than the input's. We can use the alignment
5008 -- of the component type of an array if a type is an unpacked
5011 if Present (Alignment_Clause (Otyp)) then
5012 Oalign := Expr_Value (Expression (Alignment_Clause (Otyp)));
5014 elsif Is_Array_Type (Otyp)
5015 and then Present (Alignment_Clause (Component_Type (Otyp)))
5017 Oalign := Expr_Value (Expression (Alignment_Clause
5018 (Component_Type (Otyp))));
5021 if Present (Alignment_Clause (Ityp)) then
5022 Ialign := Expr_Value (Expression (Alignment_Clause (Ityp)));
5024 elsif Is_Array_Type (Ityp)
5025 and then Present (Alignment_Clause (Component_Type (Ityp)))
5027 Ialign := Expr_Value (Expression (Alignment_Clause
5028 (Component_Type (Ityp))));
5031 if Ialign /= No_Uint and then Ialign > Maximum_Alignment then
5034 elsif Ialign /= No_Uint and then Oalign /= No_Uint
5035 and then Ialign <= Oalign
5039 -- Otherwise, Gigi cannot handle this and we must make a temporary
5044 end Safe_Unchecked_Type_Conversion;
5046 ---------------------------------
5047 -- Set_Current_Value_Condition --
5048 ---------------------------------
5050 -- Note: the implementation of this procedure is very closely tied to the
5051 -- implementation of Get_Current_Value_Condition. Here we set required
5052 -- Current_Value fields, and in Get_Current_Value_Condition, we interpret
5053 -- them, so they must have a consistent view.
5055 procedure Set_Current_Value_Condition (Cnode : Node_Id) is
5057 procedure Set_Entity_Current_Value (N : Node_Id);
5058 -- If N is an entity reference, where the entity is of an appropriate
5059 -- kind, then set the current value of this entity to Cnode, unless
5060 -- there is already a definite value set there.
5062 procedure Set_Expression_Current_Value (N : Node_Id);
5063 -- If N is of an appropriate form, sets an appropriate entry in current
5064 -- value fields of relevant entities. Multiple entities can be affected
5065 -- in the case of an AND or AND THEN.
5067 ------------------------------
5068 -- Set_Entity_Current_Value --
5069 ------------------------------
5071 procedure Set_Entity_Current_Value (N : Node_Id) is
5073 if Is_Entity_Name (N) then
5075 Ent : constant Entity_Id := Entity (N);
5078 -- Don't capture if not safe to do so
5080 if not Safe_To_Capture_Value (N, Ent, Cond => True) then
5084 -- Here we have a case where the Current_Value field may
5085 -- need to be set. We set it if it is not already set to a
5086 -- compile time expression value.
5088 -- Note that this represents a decision that one condition
5089 -- blots out another previous one. That's certainly right
5090 -- if they occur at the same level. If the second one is
5091 -- nested, then the decision is neither right nor wrong (it
5092 -- would be equally OK to leave the outer one in place, or
5093 -- take the new inner one. Really we should record both, but
5094 -- our data structures are not that elaborate.
5096 if Nkind (Current_Value (Ent)) not in N_Subexpr then
5097 Set_Current_Value (Ent, Cnode);
5101 end Set_Entity_Current_Value;
5103 ----------------------------------
5104 -- Set_Expression_Current_Value --
5105 ----------------------------------
5107 procedure Set_Expression_Current_Value (N : Node_Id) is
5113 -- Loop to deal with (ignore for now) any NOT operators present. The
5114 -- presence of NOT operators will be handled properly when we call
5115 -- Get_Current_Value_Condition.
5117 while Nkind (Cond) = N_Op_Not loop
5118 Cond := Right_Opnd (Cond);
5121 -- For an AND or AND THEN, recursively process operands
5123 if Nkind (Cond) = N_Op_And or else Nkind (Cond) = N_And_Then then
5124 Set_Expression_Current_Value (Left_Opnd (Cond));
5125 Set_Expression_Current_Value (Right_Opnd (Cond));
5129 -- Check possible relational operator
5131 if Nkind (Cond) in N_Op_Compare then
5132 if Compile_Time_Known_Value (Right_Opnd (Cond)) then
5133 Set_Entity_Current_Value (Left_Opnd (Cond));
5134 elsif Compile_Time_Known_Value (Left_Opnd (Cond)) then
5135 Set_Entity_Current_Value (Right_Opnd (Cond));
5138 -- Check possible boolean variable reference
5141 Set_Entity_Current_Value (Cond);
5143 end Set_Expression_Current_Value;
5145 -- Start of processing for Set_Current_Value_Condition
5148 Set_Expression_Current_Value (Condition (Cnode));
5149 end Set_Current_Value_Condition;
5151 --------------------------
5152 -- Set_Elaboration_Flag --
5153 --------------------------
5155 procedure Set_Elaboration_Flag (N : Node_Id; Spec_Id : Entity_Id) is
5156 Loc : constant Source_Ptr := Sloc (N);
5157 Ent : constant Entity_Id := Elaboration_Entity (Spec_Id);
5161 if Present (Ent) then
5163 -- Nothing to do if at the compilation unit level, because in this
5164 -- case the flag is set by the binder generated elaboration routine.
5166 if Nkind (Parent (N)) = N_Compilation_Unit then
5169 -- Here we do need to generate an assignment statement
5172 Check_Restriction (No_Elaboration_Code, N);
5174 Make_Assignment_Statement (Loc,
5175 Name => New_Occurrence_Of (Ent, Loc),
5176 Expression => New_Occurrence_Of (Standard_True, Loc));
5178 if Nkind (Parent (N)) = N_Subunit then
5179 Insert_After (Corresponding_Stub (Parent (N)), Asn);
5181 Insert_After (N, Asn);
5186 -- Kill current value indication. This is necessary because the
5187 -- tests of this flag are inserted out of sequence and must not
5188 -- pick up bogus indications of the wrong constant value.
5190 Set_Current_Value (Ent, Empty);
5193 end Set_Elaboration_Flag;
5195 ----------------------------
5196 -- Set_Renamed_Subprogram --
5197 ----------------------------
5199 procedure Set_Renamed_Subprogram (N : Node_Id; E : Entity_Id) is
5201 -- If input node is an identifier, we can just reset it
5203 if Nkind (N) = N_Identifier then
5204 Set_Chars (N, Chars (E));
5207 -- Otherwise we have to do a rewrite, preserving Comes_From_Source
5211 CS : constant Boolean := Comes_From_Source (N);
5213 Rewrite (N, Make_Identifier (Sloc (N), Chars => Chars (E)));
5215 Set_Comes_From_Source (N, CS);
5216 Set_Analyzed (N, True);
5219 end Set_Renamed_Subprogram;
5221 ----------------------------------
5222 -- Silly_Boolean_Array_Not_Test --
5223 ----------------------------------
5225 -- This procedure implements an odd and silly test. We explicitly check
5226 -- for the case where the 'First of the component type is equal to the
5227 -- 'Last of this component type, and if this is the case, we make sure
5228 -- that constraint error is raised. The reason is that the NOT is bound
5229 -- to cause CE in this case, and we will not otherwise catch it.
5231 -- No such check is required for AND and OR, since for both these cases
5232 -- False op False = False, and True op True = True. For the XOR case,
5233 -- see Silly_Boolean_Array_Xor_Test.
5235 -- Believe it or not, this was reported as a bug. Note that nearly
5236 -- always, the test will evaluate statically to False, so the code will
5237 -- be statically removed, and no extra overhead caused.
5239 procedure Silly_Boolean_Array_Not_Test (N : Node_Id; T : Entity_Id) is
5240 Loc : constant Source_Ptr := Sloc (N);
5241 CT : constant Entity_Id := Component_Type (T);
5244 -- The check we install is
5246 -- constraint_error when
5247 -- component_type'first = component_type'last
5248 -- and then array_type'Length /= 0)
5250 -- We need the last guard because we don't want to raise CE for empty
5251 -- arrays since no out of range values result. (Empty arrays with a
5252 -- component type of True .. True -- very useful -- even the ACATS
5253 -- does not test that marginal case!)
5256 Make_Raise_Constraint_Error (Loc,
5262 Make_Attribute_Reference (Loc,
5263 Prefix => New_Occurrence_Of (CT, Loc),
5264 Attribute_Name => Name_First),
5267 Make_Attribute_Reference (Loc,
5268 Prefix => New_Occurrence_Of (CT, Loc),
5269 Attribute_Name => Name_Last)),
5271 Right_Opnd => Make_Non_Empty_Check (Loc, Right_Opnd (N))),
5272 Reason => CE_Range_Check_Failed));
5273 end Silly_Boolean_Array_Not_Test;
5275 ----------------------------------
5276 -- Silly_Boolean_Array_Xor_Test --
5277 ----------------------------------
5279 -- This procedure implements an odd and silly test. We explicitly check
5280 -- for the XOR case where the component type is True .. True, since this
5281 -- will raise constraint error. A special check is required since CE
5282 -- will not be generated otherwise (cf Expand_Packed_Not).
5284 -- No such check is required for AND and OR, since for both these cases
5285 -- False op False = False, and True op True = True, and no check is
5286 -- required for the case of False .. False, since False xor False = False.
5287 -- See also Silly_Boolean_Array_Not_Test
5289 procedure Silly_Boolean_Array_Xor_Test (N : Node_Id; T : Entity_Id) is
5290 Loc : constant Source_Ptr := Sloc (N);
5291 CT : constant Entity_Id := Component_Type (T);
5294 -- The check we install is
5296 -- constraint_error when
5297 -- Boolean (component_type'First)
5298 -- and then Boolean (component_type'Last)
5299 -- and then array_type'Length /= 0)
5301 -- We need the last guard because we don't want to raise CE for empty
5302 -- arrays since no out of range values result (Empty arrays with a
5303 -- component type of True .. True -- very useful -- even the ACATS
5304 -- does not test that marginal case!).
5307 Make_Raise_Constraint_Error (Loc,
5313 Convert_To (Standard_Boolean,
5314 Make_Attribute_Reference (Loc,
5315 Prefix => New_Occurrence_Of (CT, Loc),
5316 Attribute_Name => Name_First)),
5319 Convert_To (Standard_Boolean,
5320 Make_Attribute_Reference (Loc,
5321 Prefix => New_Occurrence_Of (CT, Loc),
5322 Attribute_Name => Name_Last))),
5324 Right_Opnd => Make_Non_Empty_Check (Loc, Right_Opnd (N))),
5325 Reason => CE_Range_Check_Failed));
5326 end Silly_Boolean_Array_Xor_Test;
5328 --------------------------
5329 -- Target_Has_Fixed_Ops --
5330 --------------------------
5332 Integer_Sized_Small : Ureal;
5333 -- Set to 2.0 ** -(Integer'Size - 1) the first time that this
5334 -- function is called (we don't want to compute it more than once!)
5336 Long_Integer_Sized_Small : Ureal;
5337 -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this
5338 -- function is called (we don't want to compute it more than once)
5340 First_Time_For_THFO : Boolean := True;
5341 -- Set to False after first call (if Fractional_Fixed_Ops_On_Target)
5343 function Target_Has_Fixed_Ops
5344 (Left_Typ : Entity_Id;
5345 Right_Typ : Entity_Id;
5346 Result_Typ : Entity_Id) return Boolean
5348 function Is_Fractional_Type (Typ : Entity_Id) return Boolean;
5349 -- Return True if the given type is a fixed-point type with a small
5350 -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have
5351 -- an absolute value less than 1.0. This is currently limited
5352 -- to fixed-point types that map to Integer or Long_Integer.
5354 ------------------------
5355 -- Is_Fractional_Type --
5356 ------------------------
5358 function Is_Fractional_Type (Typ : Entity_Id) return Boolean is
5360 if Esize (Typ) = Standard_Integer_Size then
5361 return Small_Value (Typ) = Integer_Sized_Small;
5363 elsif Esize (Typ) = Standard_Long_Integer_Size then
5364 return Small_Value (Typ) = Long_Integer_Sized_Small;
5369 end Is_Fractional_Type;
5371 -- Start of processing for Target_Has_Fixed_Ops
5374 -- Return False if Fractional_Fixed_Ops_On_Target is false
5376 if not Fractional_Fixed_Ops_On_Target then
5380 -- Here the target has Fractional_Fixed_Ops, if first time, compute
5381 -- standard constants used by Is_Fractional_Type.
5383 if First_Time_For_THFO then
5384 First_Time_For_THFO := False;
5386 Integer_Sized_Small :=
5389 Den => UI_From_Int (Standard_Integer_Size - 1),
5392 Long_Integer_Sized_Small :=
5395 Den => UI_From_Int (Standard_Long_Integer_Size - 1),
5399 -- Return True if target supports fixed-by-fixed multiply/divide
5400 -- for fractional fixed-point types (see Is_Fractional_Type) and
5401 -- the operand and result types are equivalent fractional types.
5403 return Is_Fractional_Type (Base_Type (Left_Typ))
5404 and then Is_Fractional_Type (Base_Type (Right_Typ))
5405 and then Is_Fractional_Type (Base_Type (Result_Typ))
5406 and then Esize (Left_Typ) = Esize (Right_Typ)
5407 and then Esize (Left_Typ) = Esize (Result_Typ);
5408 end Target_Has_Fixed_Ops;
5410 ------------------------------------------
5411 -- Type_May_Have_Bit_Aligned_Components --
5412 ------------------------------------------
5414 function Type_May_Have_Bit_Aligned_Components
5415 (Typ : Entity_Id) return Boolean
5418 -- Array type, check component type
5420 if Is_Array_Type (Typ) then
5422 Type_May_Have_Bit_Aligned_Components (Component_Type (Typ));
5424 -- Record type, check components
5426 elsif Is_Record_Type (Typ) then
5431 E := First_Component_Or_Discriminant (Typ);
5432 while Present (E) loop
5433 if Component_May_Be_Bit_Aligned (E)
5434 or else Type_May_Have_Bit_Aligned_Components (Etype (E))
5439 Next_Component_Or_Discriminant (E);
5445 -- Type other than array or record is always OK
5450 end Type_May_Have_Bit_Aligned_Components;
5452 ----------------------------
5453 -- Wrap_Cleanup_Procedure --
5454 ----------------------------
5456 procedure Wrap_Cleanup_Procedure (N : Node_Id) is
5457 Loc : constant Source_Ptr := Sloc (N);
5458 Stseq : constant Node_Id := Handled_Statement_Sequence (N);
5459 Stmts : constant List_Id := Statements (Stseq);
5462 if Abort_Allowed then
5463 Prepend_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Defer));
5464 Append_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Undefer));
5466 end Wrap_Cleanup_Procedure;