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
916 UT : constant Entity_Id := Underlying_Type (Etype (Comp));
919 -- If no component clause, then everything is fine, since the back end
920 -- never bit-misaligns by default, even if there is a pragma Packed for
923 if No (Component_Clause (Comp)) then
927 -- It is only array and record types that cause trouble
929 if not Is_Record_Type (UT)
930 and then not Is_Array_Type (UT)
934 -- If we know that we have a small (64 bits or less) record or small
935 -- bit-packed array, then everything is fine, since the back end can
936 -- handle these cases correctly.
938 elsif Esize (Comp) <= 64
939 and then (Is_Record_Type (UT)
940 or else Is_Bit_Packed_Array (UT))
944 -- Otherwise if the component is not byte aligned, we know we have the
945 -- nasty unaligned case.
947 elsif Normalized_First_Bit (Comp) /= Uint_0
948 or else Esize (Comp) mod System_Storage_Unit /= Uint_0
952 -- If we are large and byte aligned, then OK at this level
957 end Component_May_Be_Bit_Aligned;
959 -----------------------------------
960 -- Corresponding_Runtime_Package --
961 -----------------------------------
963 function Corresponding_Runtime_Package (Typ : Entity_Id) return RTU_Id is
964 Pkg_Id : RTU_Id := RTU_Null;
967 pragma Assert (Is_Concurrent_Type (Typ));
969 if Ekind (Typ) in Protected_Kind then
971 or else Has_Interrupt_Handler (Typ)
972 or else (Has_Attach_Handler (Typ)
973 and then not Restricted_Profile)
975 -- A protected type without entries that covers an interface and
976 -- overrides the abstract routines with protected procedures is
977 -- considered equivalent to a protected type with entries in the
978 -- context of dispatching select statements. It is sufficient to
979 -- check for the presence of an interface list in the declaration
980 -- node to recognize this case.
982 or else Present (Interface_List (Parent (Typ)))
985 or else Restriction_Active (No_Entry_Queue) = False
986 or else Number_Entries (Typ) > 1
987 or else (Has_Attach_Handler (Typ)
988 and then not Restricted_Profile)
990 Pkg_Id := System_Tasking_Protected_Objects_Entries;
992 Pkg_Id := System_Tasking_Protected_Objects_Single_Entry;
996 Pkg_Id := System_Tasking_Protected_Objects;
1001 end Corresponding_Runtime_Package;
1003 -------------------------------
1004 -- Convert_To_Actual_Subtype --
1005 -------------------------------
1007 procedure Convert_To_Actual_Subtype (Exp : Entity_Id) is
1011 Act_ST := Get_Actual_Subtype (Exp);
1013 if Act_ST = Etype (Exp) then
1018 Convert_To (Act_ST, Relocate_Node (Exp)));
1019 Analyze_And_Resolve (Exp, Act_ST);
1021 end Convert_To_Actual_Subtype;
1023 -----------------------------------
1024 -- Current_Sem_Unit_Declarations --
1025 -----------------------------------
1027 function Current_Sem_Unit_Declarations return List_Id is
1028 U : Node_Id := Unit (Cunit (Current_Sem_Unit));
1032 -- If the current unit is a package body, locate the visible
1033 -- declarations of the package spec.
1035 if Nkind (U) = N_Package_Body then
1036 U := Unit (Library_Unit (Cunit (Current_Sem_Unit)));
1039 if Nkind (U) = N_Package_Declaration then
1040 U := Specification (U);
1041 Decls := Visible_Declarations (U);
1045 Set_Visible_Declarations (U, Decls);
1049 Decls := Declarations (U);
1053 Set_Declarations (U, Decls);
1058 end Current_Sem_Unit_Declarations;
1060 -----------------------
1061 -- Duplicate_Subexpr --
1062 -----------------------
1064 function Duplicate_Subexpr
1066 Name_Req : Boolean := False) return Node_Id
1069 Remove_Side_Effects (Exp, Name_Req);
1070 return New_Copy_Tree (Exp);
1071 end Duplicate_Subexpr;
1073 ---------------------------------
1074 -- Duplicate_Subexpr_No_Checks --
1075 ---------------------------------
1077 function Duplicate_Subexpr_No_Checks
1079 Name_Req : Boolean := False) return Node_Id
1084 Remove_Side_Effects (Exp, Name_Req);
1085 New_Exp := New_Copy_Tree (Exp);
1086 Remove_Checks (New_Exp);
1088 end Duplicate_Subexpr_No_Checks;
1090 -----------------------------------
1091 -- Duplicate_Subexpr_Move_Checks --
1092 -----------------------------------
1094 function Duplicate_Subexpr_Move_Checks
1096 Name_Req : Boolean := False) return Node_Id
1101 Remove_Side_Effects (Exp, Name_Req);
1102 New_Exp := New_Copy_Tree (Exp);
1103 Remove_Checks (Exp);
1105 end Duplicate_Subexpr_Move_Checks;
1107 --------------------
1108 -- Ensure_Defined --
1109 --------------------
1111 procedure Ensure_Defined (Typ : Entity_Id; N : Node_Id) is
1115 -- An itype reference must only be created if this is a local
1116 -- itype, so that gigi can elaborate it on the proper objstack.
1119 and then Scope (Typ) = Current_Scope
1121 IR := Make_Itype_Reference (Sloc (N));
1122 Set_Itype (IR, Typ);
1123 Insert_Action (N, IR);
1127 --------------------
1128 -- Entry_Names_OK --
1129 --------------------
1131 function Entry_Names_OK return Boolean is
1134 not Restricted_Profile
1135 and then not Global_Discard_Names
1136 and then not Restriction_Active (No_Implicit_Heap_Allocations)
1137 and then not Restriction_Active (No_Local_Allocators);
1140 ---------------------
1141 -- Evolve_And_Then --
1142 ---------------------
1144 procedure Evolve_And_Then (Cond : in out Node_Id; Cond1 : Node_Id) is
1150 Make_And_Then (Sloc (Cond1),
1152 Right_Opnd => Cond1);
1154 end Evolve_And_Then;
1156 --------------------
1157 -- Evolve_Or_Else --
1158 --------------------
1160 procedure Evolve_Or_Else (Cond : in out Node_Id; Cond1 : Node_Id) is
1166 Make_Or_Else (Sloc (Cond1),
1168 Right_Opnd => Cond1);
1172 ------------------------------
1173 -- Expand_Subtype_From_Expr --
1174 ------------------------------
1176 -- This function is applicable for both static and dynamic allocation of
1177 -- objects which are constrained by an initial expression. Basically it
1178 -- transforms an unconstrained subtype indication into a constrained one.
1179 -- The expression may also be transformed in certain cases in order to
1180 -- avoid multiple evaluation. In the static allocation case, the general
1185 -- is transformed into
1187 -- Val : Constrained_Subtype_of_T := Maybe_Modified_Expr;
1189 -- Here are the main cases :
1191 -- <if Expr is a Slice>
1192 -- Val : T ([Index_Subtype (Expr)]) := Expr;
1194 -- <elsif Expr is a String Literal>
1195 -- Val : T (T'First .. T'First + Length (string literal) - 1) := Expr;
1197 -- <elsif Expr is Constrained>
1198 -- subtype T is Type_Of_Expr
1201 -- <elsif Expr is an entity_name>
1202 -- Val : T (constraints taken from Expr) := Expr;
1205 -- type Axxx is access all T;
1206 -- Rval : Axxx := Expr'ref;
1207 -- Val : T (constraints taken from Rval) := Rval.all;
1209 -- ??? note: when the Expression is allocated in the secondary stack
1210 -- we could use it directly instead of copying it by declaring
1211 -- Val : T (...) renames Rval.all
1213 procedure Expand_Subtype_From_Expr
1215 Unc_Type : Entity_Id;
1216 Subtype_Indic : Node_Id;
1219 Loc : constant Source_Ptr := Sloc (N);
1220 Exp_Typ : constant Entity_Id := Etype (Exp);
1224 -- In general we cannot build the subtype if expansion is disabled,
1225 -- because internal entities may not have been defined. However, to
1226 -- avoid some cascaded errors, we try to continue when the expression
1227 -- is an array (or string), because it is safe to compute the bounds.
1228 -- It is in fact required to do so even in a generic context, because
1229 -- there may be constants that depend on bounds of string literal.
1231 if not Expander_Active
1232 and then (No (Etype (Exp))
1233 or else Base_Type (Etype (Exp)) /= Standard_String)
1238 if Nkind (Exp) = N_Slice then
1240 Slice_Type : constant Entity_Id := Etype (First_Index (Exp_Typ));
1243 Rewrite (Subtype_Indic,
1244 Make_Subtype_Indication (Loc,
1245 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1247 Make_Index_Or_Discriminant_Constraint (Loc,
1248 Constraints => New_List
1249 (New_Reference_To (Slice_Type, Loc)))));
1251 -- This subtype indication may be used later for constraint checks
1252 -- we better make sure that if a variable was used as a bound of
1253 -- of the original slice, its value is frozen.
1255 Force_Evaluation (Low_Bound (Scalar_Range (Slice_Type)));
1256 Force_Evaluation (High_Bound (Scalar_Range (Slice_Type)));
1259 elsif Ekind (Exp_Typ) = E_String_Literal_Subtype then
1260 Rewrite (Subtype_Indic,
1261 Make_Subtype_Indication (Loc,
1262 Subtype_Mark => New_Reference_To (Unc_Type, Loc),
1264 Make_Index_Or_Discriminant_Constraint (Loc,
1265 Constraints => New_List (
1266 Make_Literal_Range (Loc,
1267 Literal_Typ => Exp_Typ)))));
1269 elsif Is_Constrained (Exp_Typ)
1270 and then not Is_Class_Wide_Type (Unc_Type)
1272 if Is_Itype (Exp_Typ) then
1274 -- Within an initialization procedure, a selected component
1275 -- denotes a component of the enclosing record, and it appears
1276 -- as an actual in a call to its own initialization procedure.
1277 -- If this component depends on the outer discriminant, we must
1278 -- generate the proper actual subtype for it.
1280 if Nkind (Exp) = N_Selected_Component
1281 and then Within_Init_Proc
1284 Decl : constant Node_Id :=
1285 Build_Actual_Subtype_Of_Component (Exp_Typ, Exp);
1287 if Present (Decl) then
1288 Insert_Action (N, Decl);
1289 T := Defining_Identifier (Decl);
1295 -- No need to generate a new one (new what???)
1303 Make_Defining_Identifier (Loc,
1304 Chars => New_Internal_Name ('T'));
1307 Make_Subtype_Declaration (Loc,
1308 Defining_Identifier => T,
1309 Subtype_Indication => New_Reference_To (Exp_Typ, Loc)));
1311 -- This type is marked as an itype even though it has an
1312 -- explicit declaration because otherwise it can be marked
1313 -- with Is_Generic_Actual_Type and generate spurious errors.
1314 -- (see sem_ch8.Analyze_Package_Renaming and sem_type.covers)
1317 Set_Associated_Node_For_Itype (T, Exp);
1320 Rewrite (Subtype_Indic, New_Reference_To (T, Loc));
1322 -- nothing needs to be done for private types with unknown discriminants
1323 -- if the underlying type is not an unconstrained composite type.
1325 elsif Is_Private_Type (Unc_Type)
1326 and then Has_Unknown_Discriminants (Unc_Type)
1327 and then (not Is_Composite_Type (Underlying_Type (Unc_Type))
1328 or else Is_Constrained (Underlying_Type (Unc_Type)))
1332 -- Case of derived type with unknown discriminants where the parent type
1333 -- also has unknown discriminants.
1335 elsif Is_Record_Type (Unc_Type)
1336 and then not Is_Class_Wide_Type (Unc_Type)
1337 and then Has_Unknown_Discriminants (Unc_Type)
1338 and then Has_Unknown_Discriminants (Underlying_Type (Unc_Type))
1340 -- Nothing to be done if no underlying record view available
1342 if No (Underlying_Record_View (Unc_Type)) then
1345 -- Otherwise use the Underlying_Record_View to create the proper
1346 -- constrained subtype for an object of a derived type with unknown
1350 Remove_Side_Effects (Exp);
1351 Rewrite (Subtype_Indic,
1352 Make_Subtype_From_Expr (Exp, Underlying_Record_View (Unc_Type)));
1355 -- Renamings of class-wide interface types require no equivalent
1356 -- constrained type declarations because we only need to reference
1357 -- the tag component associated with the interface.
1360 and then Nkind (N) = N_Object_Renaming_Declaration
1361 and then Is_Interface (Unc_Type)
1363 pragma Assert (Is_Class_Wide_Type (Unc_Type));
1366 -- In Ada95, nothing to be done if the type of the expression is
1367 -- limited, because in this case the expression cannot be copied,
1368 -- and its use can only be by reference.
1370 -- In Ada2005, the context can be an object declaration whose expression
1371 -- is a function that returns in place. If the nominal subtype has
1372 -- unknown discriminants, the call still provides constraints on the
1373 -- object, and we have to create an actual subtype from it.
1375 -- If the type is class-wide, the expression is dynamically tagged and
1376 -- we do not create an actual subtype either. Ditto for an interface.
1378 elsif Is_Limited_Type (Exp_Typ)
1380 (Is_Class_Wide_Type (Exp_Typ)
1381 or else Is_Interface (Exp_Typ)
1382 or else not Has_Unknown_Discriminants (Exp_Typ)
1383 or else not Is_Composite_Type (Unc_Type))
1387 -- For limited objects initialized with build in place function calls,
1388 -- nothing to be done; otherwise we prematurely introduce an N_Reference
1389 -- node in the expression initializing the object, which breaks the
1390 -- circuitry that detects and adds the additional arguments to the
1393 elsif Is_Build_In_Place_Function_Call (Exp) then
1397 Remove_Side_Effects (Exp);
1398 Rewrite (Subtype_Indic,
1399 Make_Subtype_From_Expr (Exp, Unc_Type));
1401 end Expand_Subtype_From_Expr;
1403 --------------------
1404 -- Find_Init_Call --
1405 --------------------
1407 function Find_Init_Call
1409 Rep_Clause : Node_Id) return Node_Id
1411 Typ : constant Entity_Id := Etype (Var);
1413 Init_Proc : Entity_Id;
1414 -- Initialization procedure for Typ
1416 function Find_Init_Call_In_List (From : Node_Id) return Node_Id;
1417 -- Look for init call for Var starting at From and scanning the
1418 -- enclosing list until Rep_Clause or the end of the list is reached.
1420 ----------------------------
1421 -- Find_Init_Call_In_List --
1422 ----------------------------
1424 function Find_Init_Call_In_List (From : Node_Id) return Node_Id is
1425 Init_Call : Node_Id;
1429 while Present (Init_Call) and then Init_Call /= Rep_Clause loop
1430 if Nkind (Init_Call) = N_Procedure_Call_Statement
1431 and then Is_Entity_Name (Name (Init_Call))
1432 and then Entity (Name (Init_Call)) = Init_Proc
1440 end Find_Init_Call_In_List;
1442 Init_Call : Node_Id;
1444 -- Start of processing for Find_Init_Call
1447 if not Has_Non_Null_Base_Init_Proc (Typ) then
1448 -- No init proc for the type, so obviously no call to be found
1453 Init_Proc := Base_Init_Proc (Typ);
1455 -- First scan the list containing the declaration of Var
1457 Init_Call := Find_Init_Call_In_List (From => Next (Parent (Var)));
1459 -- If not found, also look on Var's freeze actions list, if any, since
1460 -- the init call may have been moved there (case of an address clause
1461 -- applying to Var).
1463 if No (Init_Call) and then Present (Freeze_Node (Var)) then
1464 Init_Call := Find_Init_Call_In_List
1465 (First (Actions (Freeze_Node (Var))));
1471 ------------------------
1472 -- Find_Interface_ADT --
1473 ------------------------
1475 function Find_Interface_ADT
1477 Iface : Entity_Id) return Elmt_Id
1480 Typ : Entity_Id := T;
1483 pragma Assert (Is_Interface (Iface));
1485 -- Handle private types
1487 if Has_Private_Declaration (Typ)
1488 and then Present (Full_View (Typ))
1490 Typ := Full_View (Typ);
1493 -- Handle access types
1495 if Is_Access_Type (Typ) then
1496 Typ := Directly_Designated_Type (Typ);
1499 -- Handle task and protected types implementing interfaces
1501 if Is_Concurrent_Type (Typ) then
1502 Typ := Corresponding_Record_Type (Typ);
1506 (not Is_Class_Wide_Type (Typ)
1507 and then Ekind (Typ) /= E_Incomplete_Type);
1509 if Is_Ancestor (Iface, Typ) then
1510 return First_Elmt (Access_Disp_Table (Typ));
1514 Next_Elmt (Next_Elmt (First_Elmt (Access_Disp_Table (Typ))));
1516 and then Present (Related_Type (Node (ADT)))
1517 and then Related_Type (Node (ADT)) /= Iface
1518 and then not Is_Ancestor (Iface, Related_Type (Node (ADT)))
1523 pragma Assert (Present (Related_Type (Node (ADT))));
1526 end Find_Interface_ADT;
1528 ------------------------
1529 -- Find_Interface_Tag --
1530 ------------------------
1532 function Find_Interface_Tag
1534 Iface : Entity_Id) return Entity_Id
1537 Found : Boolean := False;
1538 Typ : Entity_Id := T;
1540 procedure Find_Tag (Typ : Entity_Id);
1541 -- Internal subprogram used to recursively climb to the ancestors
1547 procedure Find_Tag (Typ : Entity_Id) is
1552 -- This routine does not handle the case in which the interface is an
1553 -- ancestor of Typ. That case is handled by the enclosing subprogram.
1555 pragma Assert (Typ /= Iface);
1557 -- Climb to the root type handling private types
1559 if Present (Full_View (Etype (Typ))) then
1560 if Full_View (Etype (Typ)) /= Typ then
1561 Find_Tag (Full_View (Etype (Typ)));
1564 elsif Etype (Typ) /= Typ then
1565 Find_Tag (Etype (Typ));
1568 -- Traverse the list of interfaces implemented by the type
1571 and then Present (Interfaces (Typ))
1572 and then not (Is_Empty_Elmt_List (Interfaces (Typ)))
1574 -- Skip the tag associated with the primary table
1576 pragma Assert (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
1577 AI_Tag := Next_Tag_Component (First_Tag_Component (Typ));
1578 pragma Assert (Present (AI_Tag));
1580 AI_Elmt := First_Elmt (Interfaces (Typ));
1581 while Present (AI_Elmt) loop
1582 AI := Node (AI_Elmt);
1584 if AI = Iface or else Is_Ancestor (Iface, AI) then
1589 AI_Tag := Next_Tag_Component (AI_Tag);
1590 Next_Elmt (AI_Elmt);
1595 -- Start of processing for Find_Interface_Tag
1598 pragma Assert (Is_Interface (Iface));
1600 -- Handle access types
1602 if Is_Access_Type (Typ) then
1603 Typ := Directly_Designated_Type (Typ);
1606 -- Handle class-wide types
1608 if Is_Class_Wide_Type (Typ) then
1609 Typ := Root_Type (Typ);
1612 -- Handle private types
1614 if Has_Private_Declaration (Typ)
1615 and then Present (Full_View (Typ))
1617 Typ := Full_View (Typ);
1620 -- Handle entities from the limited view
1622 if Ekind (Typ) = E_Incomplete_Type then
1623 pragma Assert (Present (Non_Limited_View (Typ)));
1624 Typ := Non_Limited_View (Typ);
1627 -- Handle task and protected types implementing interfaces
1629 if Is_Concurrent_Type (Typ) then
1630 Typ := Corresponding_Record_Type (Typ);
1633 -- If the interface is an ancestor of the type, then it shared the
1634 -- primary dispatch table.
1636 if Is_Ancestor (Iface, Typ) then
1637 pragma Assert (Etype (First_Tag_Component (Typ)) = RTE (RE_Tag));
1638 return First_Tag_Component (Typ);
1640 -- Otherwise we need to search for its associated tag component
1644 pragma Assert (Found);
1647 end Find_Interface_Tag;
1653 function Find_Prim_Op (T : Entity_Id; Name : Name_Id) return Entity_Id is
1655 Typ : Entity_Id := T;
1659 if Is_Class_Wide_Type (Typ) then
1660 Typ := Root_Type (Typ);
1663 Typ := Underlying_Type (Typ);
1665 -- Loop through primitive operations
1667 Prim := First_Elmt (Primitive_Operations (Typ));
1668 while Present (Prim) loop
1671 -- We can retrieve primitive operations by name if it is an internal
1672 -- name. For equality we must check that both of its operands have
1673 -- the same type, to avoid confusion with user-defined equalities
1674 -- than may have a non-symmetric signature.
1676 exit when Chars (Op) = Name
1679 or else Etype (First_Entity (Op)) = Etype (Last_Entity (Op)));
1683 -- Raise Program_Error if no primitive found
1686 raise Program_Error;
1697 function Find_Prim_Op
1699 Name : TSS_Name_Type) return Entity_Id
1702 Typ : Entity_Id := T;
1705 if Is_Class_Wide_Type (Typ) then
1706 Typ := Root_Type (Typ);
1709 Typ := Underlying_Type (Typ);
1711 Prim := First_Elmt (Primitive_Operations (Typ));
1712 while not Is_TSS (Node (Prim), Name) loop
1715 -- Raise program error if no primitive found
1718 raise Program_Error;
1725 ----------------------------
1726 -- Find_Protection_Object --
1727 ----------------------------
1729 function Find_Protection_Object (Scop : Entity_Id) return Entity_Id is
1734 while Present (S) loop
1735 if (Ekind (S) = E_Entry
1736 or else Ekind (S) = E_Entry_Family
1737 or else Ekind (S) = E_Function
1738 or else Ekind (S) = E_Procedure)
1739 and then Present (Protection_Object (S))
1741 return Protection_Object (S);
1747 -- If we do not find a Protection object in the scope chain, then
1748 -- something has gone wrong, most likely the object was never created.
1750 raise Program_Error;
1751 end Find_Protection_Object;
1753 ----------------------
1754 -- Force_Evaluation --
1755 ----------------------
1757 procedure Force_Evaluation (Exp : Node_Id; Name_Req : Boolean := False) is
1759 Remove_Side_Effects (Exp, Name_Req, Variable_Ref => True);
1760 end Force_Evaluation;
1762 ------------------------
1763 -- Generate_Poll_Call --
1764 ------------------------
1766 procedure Generate_Poll_Call (N : Node_Id) is
1768 -- No poll call if polling not active
1770 if not Polling_Required then
1773 -- Otherwise generate require poll call
1776 Insert_Before_And_Analyze (N,
1777 Make_Procedure_Call_Statement (Sloc (N),
1778 Name => New_Occurrence_Of (RTE (RE_Poll), Sloc (N))));
1780 end Generate_Poll_Call;
1782 ---------------------------------
1783 -- Get_Current_Value_Condition --
1784 ---------------------------------
1786 -- Note: the implementation of this procedure is very closely tied to the
1787 -- implementation of Set_Current_Value_Condition. In the Get procedure, we
1788 -- interpret Current_Value fields set by the Set procedure, so the two
1789 -- procedures need to be closely coordinated.
1791 procedure Get_Current_Value_Condition
1796 Loc : constant Source_Ptr := Sloc (Var);
1797 Ent : constant Entity_Id := Entity (Var);
1799 procedure Process_Current_Value_Condition
1802 -- N is an expression which holds either True (S = True) or False (S =
1803 -- False) in the condition. This procedure digs out the expression and
1804 -- if it refers to Ent, sets Op and Val appropriately.
1806 -------------------------------------
1807 -- Process_Current_Value_Condition --
1808 -------------------------------------
1810 procedure Process_Current_Value_Condition
1821 -- Deal with NOT operators, inverting sense
1823 while Nkind (Cond) = N_Op_Not loop
1824 Cond := Right_Opnd (Cond);
1828 -- Deal with AND THEN and AND cases
1830 if Nkind (Cond) = N_And_Then
1831 or else Nkind (Cond) = N_Op_And
1833 -- Don't ever try to invert a condition that is of the form
1834 -- of an AND or AND THEN (since we are not doing sufficiently
1835 -- general processing to allow this).
1837 if Sens = False then
1843 -- Recursively process AND and AND THEN branches
1845 Process_Current_Value_Condition (Left_Opnd (Cond), True);
1847 if Op /= N_Empty then
1851 Process_Current_Value_Condition (Right_Opnd (Cond), True);
1854 -- Case of relational operator
1856 elsif Nkind (Cond) in N_Op_Compare then
1859 -- Invert sense of test if inverted test
1861 if Sens = False then
1863 when N_Op_Eq => Op := N_Op_Ne;
1864 when N_Op_Ne => Op := N_Op_Eq;
1865 when N_Op_Lt => Op := N_Op_Ge;
1866 when N_Op_Gt => Op := N_Op_Le;
1867 when N_Op_Le => Op := N_Op_Gt;
1868 when N_Op_Ge => Op := N_Op_Lt;
1869 when others => raise Program_Error;
1873 -- Case of entity op value
1875 if Is_Entity_Name (Left_Opnd (Cond))
1876 and then Ent = Entity (Left_Opnd (Cond))
1877 and then Compile_Time_Known_Value (Right_Opnd (Cond))
1879 Val := Right_Opnd (Cond);
1881 -- Case of value op entity
1883 elsif Is_Entity_Name (Right_Opnd (Cond))
1884 and then Ent = Entity (Right_Opnd (Cond))
1885 and then Compile_Time_Known_Value (Left_Opnd (Cond))
1887 Val := Left_Opnd (Cond);
1889 -- We are effectively swapping operands
1892 when N_Op_Eq => null;
1893 when N_Op_Ne => null;
1894 when N_Op_Lt => Op := N_Op_Gt;
1895 when N_Op_Gt => Op := N_Op_Lt;
1896 when N_Op_Le => Op := N_Op_Ge;
1897 when N_Op_Ge => Op := N_Op_Le;
1898 when others => raise Program_Error;
1907 -- Case of Boolean variable reference, return as though the
1908 -- reference had said var = True.
1911 if Is_Entity_Name (Cond)
1912 and then Ent = Entity (Cond)
1914 Val := New_Occurrence_Of (Standard_True, Sloc (Cond));
1916 if Sens = False then
1923 end Process_Current_Value_Condition;
1925 -- Start of processing for Get_Current_Value_Condition
1931 -- Immediate return, nothing doing, if this is not an object
1933 if Ekind (Ent) not in Object_Kind then
1937 -- Otherwise examine current value
1940 CV : constant Node_Id := Current_Value (Ent);
1945 -- If statement. Condition is known true in THEN section, known False
1946 -- in any ELSIF or ELSE part, and unknown outside the IF statement.
1948 if Nkind (CV) = N_If_Statement then
1950 -- Before start of IF statement
1952 if Loc < Sloc (CV) then
1955 -- After end of IF statement
1957 elsif Loc >= Sloc (CV) + Text_Ptr (UI_To_Int (End_Span (CV))) then
1961 -- At this stage we know that we are within the IF statement, but
1962 -- unfortunately, the tree does not record the SLOC of the ELSE so
1963 -- we cannot use a simple SLOC comparison to distinguish between
1964 -- the then/else statements, so we have to climb the tree.
1971 while Parent (N) /= CV loop
1974 -- If we fall off the top of the tree, then that's odd, but
1975 -- perhaps it could occur in some error situation, and the
1976 -- safest response is simply to assume that the outcome of
1977 -- the condition is unknown. No point in bombing during an
1978 -- attempt to optimize things.
1985 -- Now we have N pointing to a node whose parent is the IF
1986 -- statement in question, so now we can tell if we are within
1987 -- the THEN statements.
1989 if Is_List_Member (N)
1990 and then List_Containing (N) = Then_Statements (CV)
1994 -- If the variable reference does not come from source, we
1995 -- cannot reliably tell whether it appears in the else part.
1996 -- In particular, if it appears in generated code for a node
1997 -- that requires finalization, it may be attached to a list
1998 -- that has not been yet inserted into the code. For now,
1999 -- treat it as unknown.
2001 elsif not Comes_From_Source (N) then
2004 -- Otherwise we must be in ELSIF or ELSE part
2011 -- ELSIF part. Condition is known true within the referenced
2012 -- ELSIF, known False in any subsequent ELSIF or ELSE part, and
2013 -- unknown before the ELSE part or after the IF statement.
2015 elsif Nkind (CV) = N_Elsif_Part then
2018 -- Before start of ELSIF part
2020 if Loc < Sloc (CV) then
2023 -- After end of IF statement
2025 elsif Loc >= Sloc (Stm) +
2026 Text_Ptr (UI_To_Int (End_Span (Stm)))
2031 -- Again we lack the SLOC of the ELSE, so we need to climb the
2032 -- tree to see if we are within the ELSIF part in question.
2039 while Parent (N) /= Stm loop
2042 -- If we fall off the top of the tree, then that's odd, but
2043 -- perhaps it could occur in some error situation, and the
2044 -- safest response is simply to assume that the outcome of
2045 -- the condition is unknown. No point in bombing during an
2046 -- attempt to optimize things.
2053 -- Now we have N pointing to a node whose parent is the IF
2054 -- statement in question, so see if is the ELSIF part we want.
2055 -- the THEN statements.
2060 -- Otherwise we must be in subsequent ELSIF or ELSE part
2067 -- Iteration scheme of while loop. The condition is known to be
2068 -- true within the body of the loop.
2070 elsif Nkind (CV) = N_Iteration_Scheme then
2072 Loop_Stmt : constant Node_Id := Parent (CV);
2075 -- Before start of body of loop
2077 if Loc < Sloc (Loop_Stmt) then
2080 -- After end of LOOP statement
2082 elsif Loc >= Sloc (End_Label (Loop_Stmt)) then
2085 -- We are within the body of the loop
2092 -- All other cases of Current_Value settings
2098 -- If we fall through here, then we have a reportable condition, Sens
2099 -- is True if the condition is true and False if it needs inverting.
2101 Process_Current_Value_Condition (Condition (CV), Sens);
2103 end Get_Current_Value_Condition;
2105 ---------------------------------
2106 -- Has_Controlled_Coextensions --
2107 ---------------------------------
2109 function Has_Controlled_Coextensions (Typ : Entity_Id) return Boolean is
2114 -- Only consider record types
2116 if Ekind (Typ) /= E_Record_Type
2117 and then Ekind (Typ) /= E_Record_Subtype
2122 if Has_Discriminants (Typ) then
2123 Discr := First_Discriminant (Typ);
2124 while Present (Discr) loop
2125 D_Typ := Etype (Discr);
2127 if Ekind (D_Typ) = E_Anonymous_Access_Type
2129 (Is_Controlled (Directly_Designated_Type (D_Typ))
2131 Is_Concurrent_Type (Directly_Designated_Type (D_Typ)))
2136 Next_Discriminant (Discr);
2141 end Has_Controlled_Coextensions;
2143 --------------------
2144 -- Homonym_Number --
2145 --------------------
2147 function Homonym_Number (Subp : Entity_Id) return Nat is
2153 Hom := Homonym (Subp);
2154 while Present (Hom) loop
2155 if Scope (Hom) = Scope (Subp) then
2159 Hom := Homonym (Hom);
2165 ------------------------------
2166 -- In_Unconditional_Context --
2167 ------------------------------
2169 function In_Unconditional_Context (Node : Node_Id) return Boolean is
2174 while Present (P) loop
2176 when N_Subprogram_Body =>
2179 when N_If_Statement =>
2182 when N_Loop_Statement =>
2185 when N_Case_Statement =>
2194 end In_Unconditional_Context;
2200 procedure Insert_Action (Assoc_Node : Node_Id; Ins_Action : Node_Id) is
2202 if Present (Ins_Action) then
2203 Insert_Actions (Assoc_Node, New_List (Ins_Action));
2207 -- Version with check(s) suppressed
2209 procedure Insert_Action
2210 (Assoc_Node : Node_Id; Ins_Action : Node_Id; Suppress : Check_Id)
2213 Insert_Actions (Assoc_Node, New_List (Ins_Action), Suppress);
2216 --------------------
2217 -- Insert_Actions --
2218 --------------------
2220 procedure Insert_Actions (Assoc_Node : Node_Id; Ins_Actions : List_Id) is
2224 Wrapped_Node : Node_Id := Empty;
2227 if No (Ins_Actions) or else Is_Empty_List (Ins_Actions) then
2231 -- Ignore insert of actions from inside default expression (or other
2232 -- similar "spec expression") in the special spec-expression analyze
2233 -- mode. Any insertions at this point have no relevance, since we are
2234 -- only doing the analyze to freeze the types of any static expressions.
2235 -- See section "Handling of Default Expressions" in the spec of package
2236 -- Sem for further details.
2238 if In_Spec_Expression then
2242 -- If the action derives from stuff inside a record, then the actions
2243 -- are attached to the current scope, to be inserted and analyzed on
2244 -- exit from the scope. The reason for this is that we may also
2245 -- be generating freeze actions at the same time, and they must
2246 -- eventually be elaborated in the correct order.
2248 if Is_Record_Type (Current_Scope)
2249 and then not Is_Frozen (Current_Scope)
2251 if No (Scope_Stack.Table
2252 (Scope_Stack.Last).Pending_Freeze_Actions)
2254 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions :=
2259 Scope_Stack.Table (Scope_Stack.Last).Pending_Freeze_Actions);
2265 -- We now intend to climb up the tree to find the right point to
2266 -- insert the actions. We start at Assoc_Node, unless this node is
2267 -- a subexpression in which case we start with its parent. We do this
2268 -- for two reasons. First it speeds things up. Second, if Assoc_Node
2269 -- is itself one of the special nodes like N_And_Then, then we assume
2270 -- that an initial request to insert actions for such a node does not
2271 -- expect the actions to get deposited in the node for later handling
2272 -- when the node is expanded, since clearly the node is being dealt
2273 -- with by the caller. Note that in the subexpression case, N is
2274 -- always the child we came from.
2276 -- N_Raise_xxx_Error is an annoying special case, it is a statement
2277 -- if it has type Standard_Void_Type, and a subexpression otherwise.
2278 -- otherwise. Procedure attribute references are also statements.
2280 if Nkind (Assoc_Node) in N_Subexpr
2281 and then (Nkind (Assoc_Node) in N_Raise_xxx_Error
2282 or else Etype (Assoc_Node) /= Standard_Void_Type)
2283 and then (Nkind (Assoc_Node) /= N_Attribute_Reference
2285 not Is_Procedure_Attribute_Name
2286 (Attribute_Name (Assoc_Node)))
2288 P := Assoc_Node; -- ??? does not agree with above!
2289 N := Parent (Assoc_Node);
2291 -- Non-subexpression case. Note that N is initially Empty in this
2292 -- case (N is only guaranteed Non-Empty in the subexpr case).
2299 -- Capture root of the transient scope
2301 if Scope_Is_Transient then
2302 Wrapped_Node := Node_To_Be_Wrapped;
2306 pragma Assert (Present (P));
2310 -- Case of right operand of AND THEN or OR ELSE. Put the actions
2311 -- in the Actions field of the right operand. They will be moved
2312 -- out further when the AND THEN or OR ELSE operator is expanded.
2313 -- Nothing special needs to be done for the left operand since
2314 -- in that case the actions are executed unconditionally.
2316 when N_Short_Circuit =>
2317 if N = Right_Opnd (P) then
2319 -- We are now going to either append the actions to the
2320 -- actions field of the short-circuit operation. We will
2321 -- also analyze the actions now.
2323 -- This analysis is really too early, the proper thing would
2324 -- be to just park them there now, and only analyze them if
2325 -- we find we really need them, and to it at the proper
2326 -- final insertion point. However attempting to this proved
2327 -- tricky, so for now we just kill current values before and
2328 -- after the analyze call to make sure we avoid peculiar
2329 -- optimizations from this out of order insertion.
2331 Kill_Current_Values;
2333 if Present (Actions (P)) then
2334 Insert_List_After_And_Analyze
2335 (Last (Actions (P)), Ins_Actions);
2337 Set_Actions (P, Ins_Actions);
2338 Analyze_List (Actions (P));
2341 Kill_Current_Values;
2346 -- Then or Else operand of conditional expression. Add actions to
2347 -- Then_Actions or Else_Actions field as appropriate. The actions
2348 -- will be moved further out when the conditional is expanded.
2350 when N_Conditional_Expression =>
2352 ThenX : constant Node_Id := Next (First (Expressions (P)));
2353 ElseX : constant Node_Id := Next (ThenX);
2356 -- Actions belong to the then expression, temporarily
2357 -- place them as Then_Actions of the conditional expr.
2358 -- They will be moved to the proper place later when
2359 -- the conditional expression is expanded.
2362 if Present (Then_Actions (P)) then
2363 Insert_List_After_And_Analyze
2364 (Last (Then_Actions (P)), Ins_Actions);
2366 Set_Then_Actions (P, Ins_Actions);
2367 Analyze_List (Then_Actions (P));
2372 -- Actions belong to the else expression, temporarily
2373 -- place them as Else_Actions of the conditional expr.
2374 -- They will be moved to the proper place later when
2375 -- the conditional expression is expanded.
2377 elsif N = ElseX then
2378 if Present (Else_Actions (P)) then
2379 Insert_List_After_And_Analyze
2380 (Last (Else_Actions (P)), Ins_Actions);
2382 Set_Else_Actions (P, Ins_Actions);
2383 Analyze_List (Else_Actions (P));
2388 -- Actions belong to the condition. In this case they are
2389 -- unconditionally executed, and so we can continue the
2390 -- search for the proper insert point.
2397 -- Case of appearing in the condition of a while expression or
2398 -- elsif. We insert the actions into the Condition_Actions field.
2399 -- They will be moved further out when the while loop or elsif
2402 when N_Iteration_Scheme |
2405 if N = Condition (P) then
2406 if Present (Condition_Actions (P)) then
2407 Insert_List_After_And_Analyze
2408 (Last (Condition_Actions (P)), Ins_Actions);
2410 Set_Condition_Actions (P, Ins_Actions);
2412 -- Set the parent of the insert actions explicitly.
2413 -- This is not a syntactic field, but we need the
2414 -- parent field set, in particular so that freeze
2415 -- can understand that it is dealing with condition
2416 -- actions, and properly insert the freezing actions.
2418 Set_Parent (Ins_Actions, P);
2419 Analyze_List (Condition_Actions (P));
2425 -- Statements, declarations, pragmas, representation clauses
2430 N_Procedure_Call_Statement |
2431 N_Statement_Other_Than_Procedure_Call |
2437 -- Representation_Clause
2440 N_Attribute_Definition_Clause |
2441 N_Enumeration_Representation_Clause |
2442 N_Record_Representation_Clause |
2446 N_Abstract_Subprogram_Declaration |
2448 N_Exception_Declaration |
2449 N_Exception_Renaming_Declaration |
2450 N_Formal_Abstract_Subprogram_Declaration |
2451 N_Formal_Concrete_Subprogram_Declaration |
2452 N_Formal_Object_Declaration |
2453 N_Formal_Type_Declaration |
2454 N_Full_Type_Declaration |
2455 N_Function_Instantiation |
2456 N_Generic_Function_Renaming_Declaration |
2457 N_Generic_Package_Declaration |
2458 N_Generic_Package_Renaming_Declaration |
2459 N_Generic_Procedure_Renaming_Declaration |
2460 N_Generic_Subprogram_Declaration |
2461 N_Implicit_Label_Declaration |
2462 N_Incomplete_Type_Declaration |
2463 N_Number_Declaration |
2464 N_Object_Declaration |
2465 N_Object_Renaming_Declaration |
2467 N_Package_Body_Stub |
2468 N_Package_Declaration |
2469 N_Package_Instantiation |
2470 N_Package_Renaming_Declaration |
2471 N_Private_Extension_Declaration |
2472 N_Private_Type_Declaration |
2473 N_Procedure_Instantiation |
2475 N_Protected_Body_Stub |
2476 N_Protected_Type_Declaration |
2477 N_Single_Task_Declaration |
2479 N_Subprogram_Body_Stub |
2480 N_Subprogram_Declaration |
2481 N_Subprogram_Renaming_Declaration |
2482 N_Subtype_Declaration |
2485 N_Task_Type_Declaration |
2487 -- Freeze entity behaves like a declaration or statement
2491 -- Do not insert here if the item is not a list member (this
2492 -- happens for example with a triggering statement, and the
2493 -- proper approach is to insert before the entire select).
2495 if not Is_List_Member (P) then
2498 -- Do not insert if parent of P is an N_Component_Association
2499 -- node (i.e. we are in the context of an N_Aggregate or
2500 -- N_Extension_Aggregate node. In this case we want to insert
2501 -- before the entire aggregate.
2503 elsif Nkind (Parent (P)) = N_Component_Association then
2506 -- Do not insert if the parent of P is either an N_Variant
2507 -- node or an N_Record_Definition node, meaning in either
2508 -- case that P is a member of a component list, and that
2509 -- therefore the actions should be inserted outside the
2510 -- complete record declaration.
2512 elsif Nkind (Parent (P)) = N_Variant
2513 or else Nkind (Parent (P)) = N_Record_Definition
2517 -- Do not insert freeze nodes within the loop generated for
2518 -- an aggregate, because they may be elaborated too late for
2519 -- subsequent use in the back end: within a package spec the
2520 -- loop is part of the elaboration procedure and is only
2521 -- elaborated during the second pass.
2522 -- If the loop comes from source, or the entity is local to
2523 -- the loop itself it must remain within.
2525 elsif Nkind (Parent (P)) = N_Loop_Statement
2526 and then not Comes_From_Source (Parent (P))
2527 and then Nkind (First (Ins_Actions)) = N_Freeze_Entity
2529 Scope (Entity (First (Ins_Actions))) /= Current_Scope
2533 -- Otherwise we can go ahead and do the insertion
2535 elsif P = Wrapped_Node then
2536 Store_Before_Actions_In_Scope (Ins_Actions);
2540 Insert_List_Before_And_Analyze (P, Ins_Actions);
2544 -- A special case, N_Raise_xxx_Error can act either as a
2545 -- statement or a subexpression. We tell the difference
2546 -- by looking at the Etype. It is set to Standard_Void_Type
2547 -- in the statement case.
2550 N_Raise_xxx_Error =>
2551 if Etype (P) = Standard_Void_Type then
2552 if P = Wrapped_Node then
2553 Store_Before_Actions_In_Scope (Ins_Actions);
2555 Insert_List_Before_And_Analyze (P, Ins_Actions);
2560 -- In the subexpression case, keep climbing
2566 -- If a component association appears within a loop created for
2567 -- an array aggregate, attach the actions to the association so
2568 -- they can be subsequently inserted within the loop. For other
2569 -- component associations insert outside of the aggregate. For
2570 -- an association that will generate a loop, its Loop_Actions
2571 -- attribute is already initialized (see exp_aggr.adb).
2573 -- The list of loop_actions can in turn generate additional ones,
2574 -- that are inserted before the associated node. If the associated
2575 -- node is outside the aggregate, the new actions are collected
2576 -- at the end of the loop actions, to respect the order in which
2577 -- they are to be elaborated.
2580 N_Component_Association =>
2581 if Nkind (Parent (P)) = N_Aggregate
2582 and then Present (Loop_Actions (P))
2584 if Is_Empty_List (Loop_Actions (P)) then
2585 Set_Loop_Actions (P, Ins_Actions);
2586 Analyze_List (Ins_Actions);
2593 -- Check whether these actions were generated
2594 -- by a declaration that is part of the loop_
2595 -- actions for the component_association.
2598 while Present (Decl) loop
2599 exit when Parent (Decl) = P
2600 and then Is_List_Member (Decl)
2602 List_Containing (Decl) = Loop_Actions (P);
2603 Decl := Parent (Decl);
2606 if Present (Decl) then
2607 Insert_List_Before_And_Analyze
2608 (Decl, Ins_Actions);
2610 Insert_List_After_And_Analyze
2611 (Last (Loop_Actions (P)), Ins_Actions);
2622 -- Another special case, an attribute denoting a procedure call
2625 N_Attribute_Reference =>
2626 if Is_Procedure_Attribute_Name (Attribute_Name (P)) then
2627 if P = Wrapped_Node then
2628 Store_Before_Actions_In_Scope (Ins_Actions);
2630 Insert_List_Before_And_Analyze (P, Ins_Actions);
2635 -- In the subexpression case, keep climbing
2641 -- For all other node types, keep climbing tree
2645 N_Accept_Alternative |
2646 N_Access_Definition |
2647 N_Access_Function_Definition |
2648 N_Access_Procedure_Definition |
2649 N_Access_To_Object_Definition |
2652 N_Case_Statement_Alternative |
2653 N_Character_Literal |
2654 N_Compilation_Unit |
2655 N_Compilation_Unit_Aux |
2656 N_Component_Clause |
2657 N_Component_Declaration |
2658 N_Component_Definition |
2660 N_Constrained_Array_Definition |
2661 N_Decimal_Fixed_Point_Definition |
2662 N_Defining_Character_Literal |
2663 N_Defining_Identifier |
2664 N_Defining_Operator_Symbol |
2665 N_Defining_Program_Unit_Name |
2666 N_Delay_Alternative |
2667 N_Delta_Constraint |
2668 N_Derived_Type_Definition |
2670 N_Digits_Constraint |
2671 N_Discriminant_Association |
2672 N_Discriminant_Specification |
2674 N_Entry_Body_Formal_Part |
2675 N_Entry_Call_Alternative |
2676 N_Entry_Declaration |
2677 N_Entry_Index_Specification |
2678 N_Enumeration_Type_Definition |
2680 N_Exception_Handler |
2682 N_Explicit_Dereference |
2683 N_Extension_Aggregate |
2684 N_Floating_Point_Definition |
2685 N_Formal_Decimal_Fixed_Point_Definition |
2686 N_Formal_Derived_Type_Definition |
2687 N_Formal_Discrete_Type_Definition |
2688 N_Formal_Floating_Point_Definition |
2689 N_Formal_Modular_Type_Definition |
2690 N_Formal_Ordinary_Fixed_Point_Definition |
2691 N_Formal_Package_Declaration |
2692 N_Formal_Private_Type_Definition |
2693 N_Formal_Signed_Integer_Type_Definition |
2695 N_Function_Specification |
2696 N_Generic_Association |
2697 N_Handled_Sequence_Of_Statements |
2700 N_Index_Or_Discriminant_Constraint |
2701 N_Indexed_Component |
2705 N_Loop_Parameter_Specification |
2707 N_Modular_Type_Definition |
2733 N_Op_Shift_Right_Arithmetic |
2737 N_Ordinary_Fixed_Point_Definition |
2739 N_Package_Specification |
2740 N_Parameter_Association |
2741 N_Parameter_Specification |
2742 N_Pop_Constraint_Error_Label |
2743 N_Pop_Program_Error_Label |
2744 N_Pop_Storage_Error_Label |
2745 N_Pragma_Argument_Association |
2746 N_Procedure_Specification |
2747 N_Protected_Definition |
2748 N_Push_Constraint_Error_Label |
2749 N_Push_Program_Error_Label |
2750 N_Push_Storage_Error_Label |
2751 N_Qualified_Expression |
2753 N_Range_Constraint |
2755 N_Real_Range_Specification |
2756 N_Record_Definition |
2758 N_Selected_Component |
2759 N_Signed_Integer_Type_Definition |
2760 N_Single_Protected_Declaration |
2764 N_Subtype_Indication |
2767 N_Terminate_Alternative |
2768 N_Triggering_Alternative |
2770 N_Unchecked_Expression |
2771 N_Unchecked_Type_Conversion |
2772 N_Unconstrained_Array_Definition |
2775 N_Use_Package_Clause |
2779 N_Validate_Unchecked_Conversion |
2786 -- Make sure that inserted actions stay in the transient scope
2788 if P = Wrapped_Node then
2789 Store_Before_Actions_In_Scope (Ins_Actions);
2793 -- If we fall through above tests, keep climbing tree
2797 if Nkind (Parent (N)) = N_Subunit then
2799 -- This is the proper body corresponding to a stub. Insertion
2800 -- must be done at the point of the stub, which is in the decla-
2801 -- rative part of the parent unit.
2803 P := Corresponding_Stub (Parent (N));
2811 -- Version with check(s) suppressed
2813 procedure Insert_Actions
2814 (Assoc_Node : Node_Id;
2815 Ins_Actions : List_Id;
2816 Suppress : Check_Id)
2819 if Suppress = All_Checks then
2821 Svg : constant Suppress_Array := Scope_Suppress;
2823 Scope_Suppress := (others => True);
2824 Insert_Actions (Assoc_Node, Ins_Actions);
2825 Scope_Suppress := Svg;
2830 Svg : constant Boolean := Scope_Suppress (Suppress);
2832 Scope_Suppress (Suppress) := True;
2833 Insert_Actions (Assoc_Node, Ins_Actions);
2834 Scope_Suppress (Suppress) := Svg;
2839 --------------------------
2840 -- Insert_Actions_After --
2841 --------------------------
2843 procedure Insert_Actions_After
2844 (Assoc_Node : Node_Id;
2845 Ins_Actions : List_Id)
2848 if Scope_Is_Transient
2849 and then Assoc_Node = Node_To_Be_Wrapped
2851 Store_After_Actions_In_Scope (Ins_Actions);
2853 Insert_List_After_And_Analyze (Assoc_Node, Ins_Actions);
2855 end Insert_Actions_After;
2857 ---------------------------------
2858 -- Insert_Library_Level_Action --
2859 ---------------------------------
2861 procedure Insert_Library_Level_Action (N : Node_Id) is
2862 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2865 Push_Scope (Cunit_Entity (Main_Unit));
2866 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
2868 if No (Actions (Aux)) then
2869 Set_Actions (Aux, New_List (N));
2871 Append (N, Actions (Aux));
2876 end Insert_Library_Level_Action;
2878 ----------------------------------
2879 -- Insert_Library_Level_Actions --
2880 ----------------------------------
2882 procedure Insert_Library_Level_Actions (L : List_Id) is
2883 Aux : constant Node_Id := Aux_Decls_Node (Cunit (Main_Unit));
2886 if Is_Non_Empty_List (L) then
2887 Push_Scope (Cunit_Entity (Main_Unit));
2888 -- ??? should this be Current_Sem_Unit instead of Main_Unit?
2890 if No (Actions (Aux)) then
2891 Set_Actions (Aux, L);
2894 Insert_List_After_And_Analyze (Last (Actions (Aux)), L);
2899 end Insert_Library_Level_Actions;
2901 ----------------------
2902 -- Inside_Init_Proc --
2903 ----------------------
2905 function Inside_Init_Proc return Boolean is
2911 and then S /= Standard_Standard
2913 if Is_Init_Proc (S) then
2921 end Inside_Init_Proc;
2923 ----------------------------
2924 -- Is_All_Null_Statements --
2925 ----------------------------
2927 function Is_All_Null_Statements (L : List_Id) return Boolean is
2932 while Present (Stm) loop
2933 if Nkind (Stm) /= N_Null_Statement then
2941 end Is_All_Null_Statements;
2943 ---------------------------------
2944 -- Is_Fully_Repped_Tagged_Type --
2945 ---------------------------------
2947 function Is_Fully_Repped_Tagged_Type (T : Entity_Id) return Boolean is
2948 U : constant Entity_Id := Underlying_Type (T);
2952 if No (U) or else not Is_Tagged_Type (U) then
2954 elsif Has_Discriminants (U) then
2956 elsif not Has_Specified_Layout (U) then
2960 -- Here we have a tagged type, see if it has any unlayed out fields
2961 -- other than a possible tag and parent fields. If so, we return False.
2963 Comp := First_Component (U);
2964 while Present (Comp) loop
2965 if not Is_Tag (Comp)
2966 and then Chars (Comp) /= Name_uParent
2967 and then No (Component_Clause (Comp))
2971 Next_Component (Comp);
2975 -- All components are layed out
2978 end Is_Fully_Repped_Tagged_Type;
2980 ----------------------------------
2981 -- Is_Library_Level_Tagged_Type --
2982 ----------------------------------
2984 function Is_Library_Level_Tagged_Type (Typ : Entity_Id) return Boolean is
2986 return Is_Tagged_Type (Typ)
2987 and then Is_Library_Level_Entity (Typ);
2988 end Is_Library_Level_Tagged_Type;
2990 ----------------------------------
2991 -- Is_Possibly_Unaligned_Object --
2992 ----------------------------------
2994 function Is_Possibly_Unaligned_Object (N : Node_Id) return Boolean is
2995 T : constant Entity_Id := Etype (N);
2998 -- If renamed object, apply test to underlying object
3000 if Is_Entity_Name (N)
3001 and then Is_Object (Entity (N))
3002 and then Present (Renamed_Object (Entity (N)))
3004 return Is_Possibly_Unaligned_Object (Renamed_Object (Entity (N)));
3007 -- Tagged and controlled types and aliased types are always aligned,
3008 -- as are concurrent types.
3011 or else Has_Controlled_Component (T)
3012 or else Is_Concurrent_Type (T)
3013 or else Is_Tagged_Type (T)
3014 or else Is_Controlled (T)
3019 -- If this is an element of a packed array, may be unaligned
3021 if Is_Ref_To_Bit_Packed_Array (N) then
3025 -- Case of component reference
3027 if Nkind (N) = N_Selected_Component then
3029 P : constant Node_Id := Prefix (N);
3030 C : constant Entity_Id := Entity (Selector_Name (N));
3035 -- If component reference is for an array with non-static bounds,
3036 -- then it is always aligned: we can only process unaligned
3037 -- arrays with static bounds (more accurately bounds known at
3040 if Is_Array_Type (T)
3041 and then not Compile_Time_Known_Bounds (T)
3046 -- If component is aliased, it is definitely properly aligned
3048 if Is_Aliased (C) then
3052 -- If component is for a type implemented as a scalar, and the
3053 -- record is packed, and the component is other than the first
3054 -- component of the record, then the component may be unaligned.
3056 if Is_Packed (Etype (P))
3057 and then Represented_As_Scalar (Etype (C))
3058 and then First_Entity (Scope (C)) /= C
3063 -- Compute maximum possible alignment for T
3065 -- If alignment is known, then that settles things
3067 if Known_Alignment (T) then
3068 M := UI_To_Int (Alignment (T));
3070 -- If alignment is not known, tentatively set max alignment
3073 M := Ttypes.Maximum_Alignment;
3075 -- We can reduce this if the Esize is known since the default
3076 -- alignment will never be more than the smallest power of 2
3077 -- that does not exceed this Esize value.
3079 if Known_Esize (T) then
3080 S := UI_To_Int (Esize (T));
3082 while (M / 2) >= S loop
3088 -- If the component reference is for a record that has a specified
3089 -- alignment, and we either know it is too small, or cannot tell,
3090 -- then the component may be unaligned
3092 if Known_Alignment (Etype (P))
3093 and then Alignment (Etype (P)) < Ttypes.Maximum_Alignment
3094 and then M > Alignment (Etype (P))
3099 -- Case of component clause present which may specify an
3100 -- unaligned position.
3102 if Present (Component_Clause (C)) then
3104 -- Otherwise we can do a test to make sure that the actual
3105 -- start position in the record, and the length, are both
3106 -- consistent with the required alignment. If not, we know
3107 -- that we are unaligned.
3110 Align_In_Bits : constant Nat := M * System_Storage_Unit;
3112 if Component_Bit_Offset (C) mod Align_In_Bits /= 0
3113 or else Esize (C) mod Align_In_Bits /= 0
3120 -- Otherwise, for a component reference, test prefix
3122 return Is_Possibly_Unaligned_Object (P);
3125 -- If not a component reference, must be aligned
3130 end Is_Possibly_Unaligned_Object;
3132 ---------------------------------
3133 -- Is_Possibly_Unaligned_Slice --
3134 ---------------------------------
3136 function Is_Possibly_Unaligned_Slice (N : Node_Id) return Boolean is
3138 -- Go to renamed object
3140 if Is_Entity_Name (N)
3141 and then Is_Object (Entity (N))
3142 and then Present (Renamed_Object (Entity (N)))
3144 return Is_Possibly_Unaligned_Slice (Renamed_Object (Entity (N)));
3147 -- The reference must be a slice
3149 if Nkind (N) /= N_Slice then
3153 -- Always assume the worst for a nested record component with a
3154 -- component clause, which gigi/gcc does not appear to handle well.
3155 -- It is not clear why this special test is needed at all ???
3157 if Nkind (Prefix (N)) = N_Selected_Component
3158 and then Nkind (Prefix (Prefix (N))) = N_Selected_Component
3160 Present (Component_Clause (Entity (Selector_Name (Prefix (N)))))
3165 -- We only need to worry if the target has strict alignment
3167 if not Target_Strict_Alignment then
3171 -- If it is a slice, then look at the array type being sliced
3174 Sarr : constant Node_Id := Prefix (N);
3175 -- Prefix of the slice, i.e. the array being sliced
3177 Styp : constant Entity_Id := Etype (Prefix (N));
3178 -- Type of the array being sliced
3184 -- The problems arise if the array object that is being sliced
3185 -- is a component of a record or array, and we cannot guarantee
3186 -- the alignment of the array within its containing object.
3188 -- To investigate this, we look at successive prefixes to see
3189 -- if we have a worrisome indexed or selected component.
3193 -- Case of array is part of an indexed component reference
3195 if Nkind (Pref) = N_Indexed_Component then
3196 Ptyp := Etype (Prefix (Pref));
3198 -- The only problematic case is when the array is packed,
3199 -- in which case we really know nothing about the alignment
3200 -- of individual components.
3202 if Is_Bit_Packed_Array (Ptyp) then
3206 -- Case of array is part of a selected component reference
3208 elsif Nkind (Pref) = N_Selected_Component then
3209 Ptyp := Etype (Prefix (Pref));
3211 -- We are definitely in trouble if the record in question
3212 -- has an alignment, and either we know this alignment is
3213 -- inconsistent with the alignment of the slice, or we
3214 -- don't know what the alignment of the slice should be.
3216 if Known_Alignment (Ptyp)
3217 and then (Unknown_Alignment (Styp)
3218 or else Alignment (Styp) > Alignment (Ptyp))
3223 -- We are in potential trouble if the record type is packed.
3224 -- We could special case when we know that the array is the
3225 -- first component, but that's not such a simple case ???
3227 if Is_Packed (Ptyp) then
3231 -- We are in trouble if there is a component clause, and
3232 -- either we do not know the alignment of the slice, or
3233 -- the alignment of the slice is inconsistent with the
3234 -- bit position specified by the component clause.
3237 Field : constant Entity_Id := Entity (Selector_Name (Pref));
3239 if Present (Component_Clause (Field))
3241 (Unknown_Alignment (Styp)
3243 (Component_Bit_Offset (Field) mod
3244 (System_Storage_Unit * Alignment (Styp))) /= 0)
3250 -- For cases other than selected or indexed components we
3251 -- know we are OK, since no issues arise over alignment.
3257 -- We processed an indexed component or selected component
3258 -- reference that looked safe, so keep checking prefixes.
3260 Pref := Prefix (Pref);
3263 end Is_Possibly_Unaligned_Slice;
3265 --------------------------------
3266 -- Is_Ref_To_Bit_Packed_Array --
3267 --------------------------------
3269 function Is_Ref_To_Bit_Packed_Array (N : Node_Id) return Boolean is
3274 if Is_Entity_Name (N)
3275 and then Is_Object (Entity (N))
3276 and then Present (Renamed_Object (Entity (N)))
3278 return Is_Ref_To_Bit_Packed_Array (Renamed_Object (Entity (N)));
3281 if Nkind (N) = N_Indexed_Component
3283 Nkind (N) = N_Selected_Component
3285 if Is_Bit_Packed_Array (Etype (Prefix (N))) then
3288 Result := Is_Ref_To_Bit_Packed_Array (Prefix (N));
3291 if Result and then Nkind (N) = N_Indexed_Component then
3292 Expr := First (Expressions (N));
3293 while Present (Expr) loop
3294 Force_Evaluation (Expr);
3304 end Is_Ref_To_Bit_Packed_Array;
3306 --------------------------------
3307 -- Is_Ref_To_Bit_Packed_Slice --
3308 --------------------------------
3310 function Is_Ref_To_Bit_Packed_Slice (N : Node_Id) return Boolean is
3312 if Nkind (N) = N_Type_Conversion then
3313 return Is_Ref_To_Bit_Packed_Slice (Expression (N));
3315 elsif Is_Entity_Name (N)
3316 and then Is_Object (Entity (N))
3317 and then Present (Renamed_Object (Entity (N)))
3319 return Is_Ref_To_Bit_Packed_Slice (Renamed_Object (Entity (N)));
3321 elsif Nkind (N) = N_Slice
3322 and then Is_Bit_Packed_Array (Etype (Prefix (N)))
3326 elsif Nkind (N) = N_Indexed_Component
3328 Nkind (N) = N_Selected_Component
3330 return Is_Ref_To_Bit_Packed_Slice (Prefix (N));
3335 end Is_Ref_To_Bit_Packed_Slice;
3337 -----------------------
3338 -- Is_Renamed_Object --
3339 -----------------------
3341 function Is_Renamed_Object (N : Node_Id) return Boolean is
3342 Pnod : constant Node_Id := Parent (N);
3343 Kind : constant Node_Kind := Nkind (Pnod);
3345 if Kind = N_Object_Renaming_Declaration then
3347 elsif Nkind_In (Kind, N_Indexed_Component, N_Selected_Component) then
3348 return Is_Renamed_Object (Pnod);
3352 end Is_Renamed_Object;
3354 ----------------------------
3355 -- Is_Untagged_Derivation --
3356 ----------------------------
3358 function Is_Untagged_Derivation (T : Entity_Id) return Boolean is
3360 return (not Is_Tagged_Type (T) and then Is_Derived_Type (T))
3362 (Is_Private_Type (T) and then Present (Full_View (T))
3363 and then not Is_Tagged_Type (Full_View (T))
3364 and then Is_Derived_Type (Full_View (T))
3365 and then Etype (Full_View (T)) /= T);
3366 end Is_Untagged_Derivation;
3368 ---------------------------
3369 -- Is_Volatile_Reference --
3370 ---------------------------
3372 function Is_Volatile_Reference (N : Node_Id) return Boolean is
3374 if Nkind (N) in N_Has_Etype
3375 and then Present (Etype (N))
3376 and then Treat_As_Volatile (Etype (N))
3380 elsif Is_Entity_Name (N) then
3381 return Treat_As_Volatile (Entity (N));
3383 elsif Nkind (N) = N_Slice then
3384 return Is_Volatile_Reference (Prefix (N));
3386 elsif Nkind_In (N, N_Indexed_Component, N_Selected_Component) then
3387 if (Is_Entity_Name (Prefix (N))
3388 and then Has_Volatile_Components (Entity (Prefix (N))))
3389 or else (Present (Etype (Prefix (N)))
3390 and then Has_Volatile_Components (Etype (Prefix (N))))
3394 return Is_Volatile_Reference (Prefix (N));
3400 end Is_Volatile_Reference;
3402 --------------------
3403 -- Kill_Dead_Code --
3404 --------------------
3406 procedure Kill_Dead_Code (N : Node_Id; Warn : Boolean := False) is
3409 Remove_Warning_Messages (N);
3413 ("?this code can never be executed and has been deleted!", N);
3416 -- Recurse into block statements and bodies to process declarations
3419 if Nkind (N) = N_Block_Statement
3420 or else Nkind (N) = N_Subprogram_Body
3421 or else Nkind (N) = N_Package_Body
3423 Kill_Dead_Code (Declarations (N), False);
3424 Kill_Dead_Code (Statements (Handled_Statement_Sequence (N)));
3426 if Nkind (N) = N_Subprogram_Body then
3427 Set_Is_Eliminated (Defining_Entity (N));
3430 elsif Nkind (N) = N_Package_Declaration then
3431 Kill_Dead_Code (Visible_Declarations (Specification (N)));
3432 Kill_Dead_Code (Private_Declarations (Specification (N)));
3434 -- ??? After this point, Delete_Tree has been called on all
3435 -- declarations in Specification (N), so references to
3436 -- entities therein look suspicious.
3439 E : Entity_Id := First_Entity (Defining_Entity (N));
3441 while Present (E) loop
3442 if Ekind (E) = E_Operator then
3443 Set_Is_Eliminated (E);
3450 -- Recurse into composite statement to kill individual statements,
3451 -- in particular instantiations.
3453 elsif Nkind (N) = N_If_Statement then
3454 Kill_Dead_Code (Then_Statements (N));
3455 Kill_Dead_Code (Elsif_Parts (N));
3456 Kill_Dead_Code (Else_Statements (N));
3458 elsif Nkind (N) = N_Loop_Statement then
3459 Kill_Dead_Code (Statements (N));
3461 elsif Nkind (N) = N_Case_Statement then
3465 Alt := First (Alternatives (N));
3466 while Present (Alt) loop
3467 Kill_Dead_Code (Statements (Alt));
3472 elsif Nkind (N) = N_Case_Statement_Alternative then
3473 Kill_Dead_Code (Statements (N));
3475 -- Deal with dead instances caused by deleting instantiations
3477 elsif Nkind (N) in N_Generic_Instantiation then
3478 Remove_Dead_Instance (N);
3483 -- Case where argument is a list of nodes to be killed
3485 procedure Kill_Dead_Code (L : List_Id; Warn : Boolean := False) is
3490 if Is_Non_Empty_List (L) then
3492 while Present (N) loop
3493 Kill_Dead_Code (N, W);
3500 ------------------------
3501 -- Known_Non_Negative --
3502 ------------------------
3504 function Known_Non_Negative (Opnd : Node_Id) return Boolean is
3506 if Is_OK_Static_Expression (Opnd)
3507 and then Expr_Value (Opnd) >= 0
3513 Lo : constant Node_Id := Type_Low_Bound (Etype (Opnd));
3517 Is_OK_Static_Expression (Lo) and then Expr_Value (Lo) >= 0;
3520 end Known_Non_Negative;
3522 --------------------
3523 -- Known_Non_Null --
3524 --------------------
3526 function Known_Non_Null (N : Node_Id) return Boolean is
3528 -- Checks for case where N is an entity reference
3530 if Is_Entity_Name (N) and then Present (Entity (N)) then
3532 E : constant Entity_Id := Entity (N);
3537 -- First check if we are in decisive conditional
3539 Get_Current_Value_Condition (N, Op, Val);
3541 if Known_Null (Val) then
3542 if Op = N_Op_Eq then
3544 elsif Op = N_Op_Ne then
3549 -- If OK to do replacement, test Is_Known_Non_Null flag
3551 if OK_To_Do_Constant_Replacement (E) then
3552 return Is_Known_Non_Null (E);
3554 -- Otherwise if not safe to do replacement, then say so
3561 -- True if access attribute
3563 elsif Nkind (N) = N_Attribute_Reference
3564 and then (Attribute_Name (N) = Name_Access
3566 Attribute_Name (N) = Name_Unchecked_Access
3568 Attribute_Name (N) = Name_Unrestricted_Access)
3572 -- True if allocator
3574 elsif Nkind (N) = N_Allocator then
3577 -- For a conversion, true if expression is known non-null
3579 elsif Nkind (N) = N_Type_Conversion then
3580 return Known_Non_Null (Expression (N));
3582 -- Above are all cases where the value could be determined to be
3583 -- non-null. In all other cases, we don't know, so return False.
3594 function Known_Null (N : Node_Id) return Boolean is
3596 -- Checks for case where N is an entity reference
3598 if Is_Entity_Name (N) and then Present (Entity (N)) then
3600 E : constant Entity_Id := Entity (N);
3605 -- Constant null value is for sure null
3607 if Ekind (E) = E_Constant
3608 and then Known_Null (Constant_Value (E))
3613 -- First check if we are in decisive conditional
3615 Get_Current_Value_Condition (N, Op, Val);
3617 if Known_Null (Val) then
3618 if Op = N_Op_Eq then
3620 elsif Op = N_Op_Ne then
3625 -- If OK to do replacement, test Is_Known_Null flag
3627 if OK_To_Do_Constant_Replacement (E) then
3628 return Is_Known_Null (E);
3630 -- Otherwise if not safe to do replacement, then say so
3637 -- True if explicit reference to null
3639 elsif Nkind (N) = N_Null then
3642 -- For a conversion, true if expression is known null
3644 elsif Nkind (N) = N_Type_Conversion then
3645 return Known_Null (Expression (N));
3647 -- Above are all cases where the value could be determined to be null.
3648 -- In all other cases, we don't know, so return False.
3655 -----------------------------
3656 -- Make_CW_Equivalent_Type --
3657 -----------------------------
3659 -- Create a record type used as an equivalent of any member of the class
3660 -- which takes its size from exp.
3662 -- Generate the following code:
3664 -- type Equiv_T is record
3665 -- _parent : T (List of discriminant constraints taken from Exp);
3666 -- Ext__50 : Storage_Array (1 .. (Exp'size - Typ'object_size)/8);
3669 -- ??? Note that this type does not guarantee same alignment as all
3672 function Make_CW_Equivalent_Type
3674 E : Node_Id) return Entity_Id
3676 Loc : constant Source_Ptr := Sloc (E);
3677 Root_Typ : constant Entity_Id := Root_Type (T);
3678 List_Def : constant List_Id := Empty_List;
3679 Comp_List : constant List_Id := New_List;
3680 Equiv_Type : Entity_Id;
3681 Range_Type : Entity_Id;
3682 Str_Type : Entity_Id;
3683 Constr_Root : Entity_Id;
3687 if not Has_Discriminants (Root_Typ) then
3688 Constr_Root := Root_Typ;
3691 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
3693 -- subtype cstr__n is T (List of discr constraints taken from Exp)
3695 Append_To (List_Def,
3696 Make_Subtype_Declaration (Loc,
3697 Defining_Identifier => Constr_Root,
3698 Subtype_Indication =>
3699 Make_Subtype_From_Expr (E, Root_Typ)));
3702 -- Generate the range subtype declaration
3704 Range_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('G'));
3706 if not Is_Interface (Root_Typ) then
3708 -- subtype rg__xx is
3709 -- Storage_Offset range 1 .. (Expr'size - typ'size) / Storage_Unit
3712 Make_Op_Subtract (Loc,
3714 Make_Attribute_Reference (Loc,
3716 OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
3717 Attribute_Name => Name_Size),
3719 Make_Attribute_Reference (Loc,
3720 Prefix => New_Reference_To (Constr_Root, Loc),
3721 Attribute_Name => Name_Object_Size));
3723 -- subtype rg__xx is
3724 -- Storage_Offset range 1 .. Expr'size / Storage_Unit
3727 Make_Attribute_Reference (Loc,
3729 OK_Convert_To (T, Duplicate_Subexpr_No_Checks (E)),
3730 Attribute_Name => Name_Size);
3733 Set_Paren_Count (Sizexpr, 1);
3735 Append_To (List_Def,
3736 Make_Subtype_Declaration (Loc,
3737 Defining_Identifier => Range_Type,
3738 Subtype_Indication =>
3739 Make_Subtype_Indication (Loc,
3740 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Offset), Loc),
3741 Constraint => Make_Range_Constraint (Loc,
3744 Low_Bound => Make_Integer_Literal (Loc, 1),
3746 Make_Op_Divide (Loc,
3747 Left_Opnd => Sizexpr,
3748 Right_Opnd => Make_Integer_Literal (Loc,
3749 Intval => System_Storage_Unit)))))));
3751 -- subtype str__nn is Storage_Array (rg__x);
3753 Str_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('S'));
3754 Append_To (List_Def,
3755 Make_Subtype_Declaration (Loc,
3756 Defining_Identifier => Str_Type,
3757 Subtype_Indication =>
3758 Make_Subtype_Indication (Loc,
3759 Subtype_Mark => New_Reference_To (RTE (RE_Storage_Array), Loc),
3761 Make_Index_Or_Discriminant_Constraint (Loc,
3763 New_List (New_Reference_To (Range_Type, Loc))))));
3765 -- type Equiv_T is record
3766 -- [ _parent : Tnn; ]
3770 Equiv_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
3772 -- When the target requires front-end layout, it's necessary to allow
3773 -- the equivalent type to be frozen so that layout can occur (when the
3774 -- associated class-wide subtype is frozen, the equivalent type will
3775 -- be frozen, see freeze.adb). For other targets, Gigi wants to have
3776 -- the equivalent type marked as frozen and deals with this type itself.
3777 -- In the Gigi case this will also avoid the generation of an init
3778 -- procedure for the type.
3780 if not Frontend_Layout_On_Target then
3781 Set_Is_Frozen (Equiv_Type);
3784 Set_Ekind (Equiv_Type, E_Record_Type);
3785 Set_Parent_Subtype (Equiv_Type, Constr_Root);
3787 if not Is_Interface (Root_Typ) then
3788 Append_To (Comp_List,
3789 Make_Component_Declaration (Loc,
3790 Defining_Identifier =>
3791 Make_Defining_Identifier (Loc, Name_uParent),
3792 Component_Definition =>
3793 Make_Component_Definition (Loc,
3794 Aliased_Present => False,
3795 Subtype_Indication => New_Reference_To (Constr_Root, Loc))));
3798 Append_To (Comp_List,
3799 Make_Component_Declaration (Loc,
3800 Defining_Identifier =>
3801 Make_Defining_Identifier (Loc,
3802 Chars => New_Internal_Name ('C')),
3803 Component_Definition =>
3804 Make_Component_Definition (Loc,
3805 Aliased_Present => False,
3806 Subtype_Indication => New_Reference_To (Str_Type, Loc))));
3808 Append_To (List_Def,
3809 Make_Full_Type_Declaration (Loc,
3810 Defining_Identifier => Equiv_Type,
3812 Make_Record_Definition (Loc,
3814 Make_Component_List (Loc,
3815 Component_Items => Comp_List,
3816 Variant_Part => Empty))));
3818 -- Suppress all checks during the analysis of the expanded code
3819 -- to avoid the generation of spurious warnings under ZFP run-time.
3821 Insert_Actions (E, List_Def, Suppress => All_Checks);
3823 end Make_CW_Equivalent_Type;
3825 ------------------------
3826 -- Make_Literal_Range --
3827 ------------------------
3829 function Make_Literal_Range
3831 Literal_Typ : Entity_Id) return Node_Id
3833 Lo : constant Node_Id :=
3834 New_Copy_Tree (String_Literal_Low_Bound (Literal_Typ));
3835 Index : constant Entity_Id := Etype (Lo);
3838 Length_Expr : constant Node_Id :=
3839 Make_Op_Subtract (Loc,
3841 Make_Integer_Literal (Loc,
3842 Intval => String_Literal_Length (Literal_Typ)),
3844 Make_Integer_Literal (Loc, 1));
3847 Set_Analyzed (Lo, False);
3849 if Is_Integer_Type (Index) then
3852 Left_Opnd => New_Copy_Tree (Lo),
3853 Right_Opnd => Length_Expr);
3856 Make_Attribute_Reference (Loc,
3857 Attribute_Name => Name_Val,
3858 Prefix => New_Occurrence_Of (Index, Loc),
3859 Expressions => New_List (
3862 Make_Attribute_Reference (Loc,
3863 Attribute_Name => Name_Pos,
3864 Prefix => New_Occurrence_Of (Index, Loc),
3865 Expressions => New_List (New_Copy_Tree (Lo))),
3866 Right_Opnd => Length_Expr)));
3873 end Make_Literal_Range;
3875 --------------------------
3876 -- Make_Non_Empty_Check --
3877 --------------------------
3879 function Make_Non_Empty_Check
3881 N : Node_Id) return Node_Id
3887 Make_Attribute_Reference (Loc,
3888 Attribute_Name => Name_Length,
3889 Prefix => Duplicate_Subexpr_No_Checks (N, Name_Req => True)),
3891 Make_Integer_Literal (Loc, 0));
3892 end Make_Non_Empty_Check;
3894 ----------------------------
3895 -- Make_Subtype_From_Expr --
3896 ----------------------------
3898 -- 1. If Expr is an unconstrained array expression, creates
3899 -- Unc_Type(Expr'first(1)..Expr'last(1),..., Expr'first(n)..Expr'last(n))
3901 -- 2. If Expr is a unconstrained discriminated type expression, creates
3902 -- Unc_Type(Expr.Discr1, ... , Expr.Discr_n)
3904 -- 3. If Expr is class-wide, creates an implicit class wide subtype
3906 function Make_Subtype_From_Expr
3908 Unc_Typ : Entity_Id) return Node_Id
3910 Loc : constant Source_Ptr := Sloc (E);
3911 List_Constr : constant List_Id := New_List;
3914 Full_Subtyp : Entity_Id;
3915 Priv_Subtyp : Entity_Id;
3920 if Is_Private_Type (Unc_Typ)
3921 and then Has_Unknown_Discriminants (Unc_Typ)
3923 -- Prepare the subtype completion, Go to base type to
3924 -- find underlying type, because the type may be a generic
3925 -- actual or an explicit subtype.
3927 Utyp := Underlying_Type (Base_Type (Unc_Typ));
3928 Full_Subtyp := Make_Defining_Identifier (Loc,
3929 New_Internal_Name ('C'));
3931 Unchecked_Convert_To
3932 (Utyp, Duplicate_Subexpr_No_Checks (E));
3933 Set_Parent (Full_Exp, Parent (E));
3936 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
3939 Make_Subtype_Declaration (Loc,
3940 Defining_Identifier => Full_Subtyp,
3941 Subtype_Indication => Make_Subtype_From_Expr (Full_Exp, Utyp)));
3943 -- Define the dummy private subtype
3945 Set_Ekind (Priv_Subtyp, Subtype_Kind (Ekind (Unc_Typ)));
3946 Set_Etype (Priv_Subtyp, Base_Type (Unc_Typ));
3947 Set_Scope (Priv_Subtyp, Full_Subtyp);
3948 Set_Is_Constrained (Priv_Subtyp);
3949 Set_Is_Tagged_Type (Priv_Subtyp, Is_Tagged_Type (Unc_Typ));
3950 Set_Is_Itype (Priv_Subtyp);
3951 Set_Associated_Node_For_Itype (Priv_Subtyp, E);
3953 if Is_Tagged_Type (Priv_Subtyp) then
3955 (Base_Type (Priv_Subtyp), Class_Wide_Type (Unc_Typ));
3956 Set_Primitive_Operations (Priv_Subtyp,
3957 Primitive_Operations (Unc_Typ));
3960 Set_Full_View (Priv_Subtyp, Full_Subtyp);
3962 return New_Reference_To (Priv_Subtyp, Loc);
3964 elsif Is_Array_Type (Unc_Typ) then
3965 for J in 1 .. Number_Dimensions (Unc_Typ) loop
3966 Append_To (List_Constr,
3969 Make_Attribute_Reference (Loc,
3970 Prefix => Duplicate_Subexpr_No_Checks (E),
3971 Attribute_Name => Name_First,
3972 Expressions => New_List (
3973 Make_Integer_Literal (Loc, J))),
3976 Make_Attribute_Reference (Loc,
3977 Prefix => Duplicate_Subexpr_No_Checks (E),
3978 Attribute_Name => Name_Last,
3979 Expressions => New_List (
3980 Make_Integer_Literal (Loc, J)))));
3983 elsif Is_Class_Wide_Type (Unc_Typ) then
3985 CW_Subtype : Entity_Id;
3986 EQ_Typ : Entity_Id := Empty;
3989 -- A class-wide equivalent type is not needed when VM_Target
3990 -- because the VM back-ends handle the class-wide object
3991 -- initialization itself (and doesn't need or want the
3992 -- additional intermediate type to handle the assignment).
3994 if Expander_Active and then Tagged_Type_Expansion then
3995 EQ_Typ := Make_CW_Equivalent_Type (Unc_Typ, E);
3998 CW_Subtype := New_Class_Wide_Subtype (Unc_Typ, E);
3999 Set_Equivalent_Type (CW_Subtype, EQ_Typ);
4001 if Present (EQ_Typ) then
4002 Set_Is_Class_Wide_Equivalent_Type (EQ_Typ);
4005 Set_Cloned_Subtype (CW_Subtype, Base_Type (Unc_Typ));
4007 return New_Occurrence_Of (CW_Subtype, Loc);
4010 -- Indefinite record type with discriminants
4013 D := First_Discriminant (Unc_Typ);
4014 while Present (D) loop
4015 Append_To (List_Constr,
4016 Make_Selected_Component (Loc,
4017 Prefix => Duplicate_Subexpr_No_Checks (E),
4018 Selector_Name => New_Reference_To (D, Loc)));
4020 Next_Discriminant (D);
4025 Make_Subtype_Indication (Loc,
4026 Subtype_Mark => New_Reference_To (Unc_Typ, Loc),
4028 Make_Index_Or_Discriminant_Constraint (Loc,
4029 Constraints => List_Constr));
4030 end Make_Subtype_From_Expr;
4032 -----------------------------
4033 -- May_Generate_Large_Temp --
4034 -----------------------------
4036 -- At the current time, the only types that we return False for (i.e.
4037 -- where we decide we know they cannot generate large temps) are ones
4038 -- where we know the size is 256 bits or less at compile time, and we
4039 -- are still not doing a thorough job on arrays and records ???
4041 function May_Generate_Large_Temp (Typ : Entity_Id) return Boolean is
4043 if not Size_Known_At_Compile_Time (Typ) then
4046 elsif Esize (Typ) /= 0 and then Esize (Typ) <= 256 then
4049 elsif Is_Array_Type (Typ)
4050 and then Present (Packed_Array_Type (Typ))
4052 return May_Generate_Large_Temp (Packed_Array_Type (Typ));
4054 -- We could do more here to find other small types ???
4059 end May_Generate_Large_Temp;
4061 ----------------------------
4062 -- New_Class_Wide_Subtype --
4063 ----------------------------
4065 function New_Class_Wide_Subtype
4066 (CW_Typ : Entity_Id;
4067 N : Node_Id) return Entity_Id
4069 Res : constant Entity_Id := Create_Itype (E_Void, N);
4070 Res_Name : constant Name_Id := Chars (Res);
4071 Res_Scope : constant Entity_Id := Scope (Res);
4074 Copy_Node (CW_Typ, Res);
4075 Set_Comes_From_Source (Res, False);
4076 Set_Sloc (Res, Sloc (N));
4078 Set_Associated_Node_For_Itype (Res, N);
4079 Set_Is_Public (Res, False); -- By default, may be changed below.
4080 Set_Public_Status (Res);
4081 Set_Chars (Res, Res_Name);
4082 Set_Scope (Res, Res_Scope);
4083 Set_Ekind (Res, E_Class_Wide_Subtype);
4084 Set_Next_Entity (Res, Empty);
4085 Set_Etype (Res, Base_Type (CW_Typ));
4087 -- For targets where front-end layout is required, reset the Is_Frozen
4088 -- status of the subtype to False (it can be implicitly set to true
4089 -- from the copy of the class-wide type). For other targets, Gigi
4090 -- doesn't want the class-wide subtype to go through the freezing
4091 -- process (though it's unclear why that causes problems and it would
4092 -- be nice to allow freezing to occur normally for all targets ???).
4094 if Frontend_Layout_On_Target then
4095 Set_Is_Frozen (Res, False);
4098 Set_Freeze_Node (Res, Empty);
4100 end New_Class_Wide_Subtype;
4102 --------------------------------
4103 -- Non_Limited_Designated_Type --
4104 ---------------------------------
4106 function Non_Limited_Designated_Type (T : Entity_Id) return Entity_Id is
4107 Desig : constant Entity_Id := Designated_Type (T);
4109 if Ekind (Desig) = E_Incomplete_Type
4110 and then Present (Non_Limited_View (Desig))
4112 return Non_Limited_View (Desig);
4116 end Non_Limited_Designated_Type;
4118 -----------------------------------
4119 -- OK_To_Do_Constant_Replacement --
4120 -----------------------------------
4122 function OK_To_Do_Constant_Replacement (E : Entity_Id) return Boolean is
4123 ES : constant Entity_Id := Scope (E);
4127 -- Do not replace statically allocated objects, because they may be
4128 -- modified outside the current scope.
4130 if Is_Statically_Allocated (E) then
4133 -- Do not replace aliased or volatile objects, since we don't know what
4134 -- else might change the value.
4136 elsif Is_Aliased (E) or else Treat_As_Volatile (E) then
4139 -- Debug flag -gnatdM disconnects this optimization
4141 elsif Debug_Flag_MM then
4144 -- Otherwise check scopes
4147 CS := Current_Scope;
4150 -- If we are in right scope, replacement is safe
4155 -- Packages do not affect the determination of safety
4157 elsif Ekind (CS) = E_Package then
4158 exit when CS = Standard_Standard;
4161 -- Blocks do not affect the determination of safety
4163 elsif Ekind (CS) = E_Block then
4166 -- Loops do not affect the determination of safety. Note that we
4167 -- kill all current values on entry to a loop, so we are just
4168 -- talking about processing within a loop here.
4170 elsif Ekind (CS) = E_Loop then
4173 -- Otherwise, the reference is dubious, and we cannot be sure that
4174 -- it is safe to do the replacement.
4183 end OK_To_Do_Constant_Replacement;
4185 ------------------------------------
4186 -- Possible_Bit_Aligned_Component --
4187 ------------------------------------
4189 function Possible_Bit_Aligned_Component (N : Node_Id) return Boolean is
4193 -- Case of indexed component
4195 when N_Indexed_Component =>
4197 P : constant Node_Id := Prefix (N);
4198 Ptyp : constant Entity_Id := Etype (P);
4201 -- If we know the component size and it is less than 64, then
4202 -- we are definitely OK. The back end always does assignment of
4203 -- misaligned small objects correctly.
4205 if Known_Static_Component_Size (Ptyp)
4206 and then Component_Size (Ptyp) <= 64
4210 -- Otherwise, we need to test the prefix, to see if we are
4211 -- indexing from a possibly unaligned component.
4214 return Possible_Bit_Aligned_Component (P);
4218 -- Case of selected component
4220 when N_Selected_Component =>
4222 P : constant Node_Id := Prefix (N);
4223 Comp : constant Entity_Id := Entity (Selector_Name (N));
4226 -- If there is no component clause, then we are in the clear
4227 -- since the back end will never misalign a large component
4228 -- unless it is forced to do so. In the clear means we need
4229 -- only the recursive test on the prefix.
4231 if Component_May_Be_Bit_Aligned (Comp) then
4234 return Possible_Bit_Aligned_Component (P);
4238 -- For a slice, test the prefix, if that is possibly misaligned,
4239 -- then for sure the slice is!
4242 return Possible_Bit_Aligned_Component (Prefix (N));
4244 -- If we have none of the above, it means that we have fallen off the
4245 -- top testing prefixes recursively, and we now have a stand alone
4246 -- object, where we don't have a problem.
4252 end Possible_Bit_Aligned_Component;
4254 -------------------------
4255 -- Remove_Side_Effects --
4256 -------------------------
4258 procedure Remove_Side_Effects
4260 Name_Req : Boolean := False;
4261 Variable_Ref : Boolean := False)
4263 Loc : constant Source_Ptr := Sloc (Exp);
4264 Exp_Type : constant Entity_Id := Etype (Exp);
4265 Svg_Suppress : constant Suppress_Array := Scope_Suppress;
4267 Ref_Type : Entity_Id;
4269 Ptr_Typ_Decl : Node_Id;
4273 function Side_Effect_Free (N : Node_Id) return Boolean;
4274 -- Determines if the tree N represents an expression that is known not
4275 -- to have side effects, and for which no processing is required.
4277 function Side_Effect_Free (L : List_Id) return Boolean;
4278 -- Determines if all elements of the list L are side effect free
4280 function Safe_Prefixed_Reference (N : Node_Id) return Boolean;
4281 -- The argument N is a construct where the Prefix is dereferenced if it
4282 -- is an access type and the result is a variable. The call returns True
4283 -- if the construct is side effect free (not considering side effects in
4284 -- other than the prefix which are to be tested by the caller).
4286 function Within_In_Parameter (N : Node_Id) return Boolean;
4287 -- Determines if N is a subcomponent of a composite in-parameter. If so,
4288 -- N is not side-effect free when the actual is global and modifiable
4289 -- indirectly from within a subprogram, because it may be passed by
4290 -- reference. The front-end must be conservative here and assume that
4291 -- this may happen with any array or record type. On the other hand, we
4292 -- cannot create temporaries for all expressions for which this
4293 -- condition is true, for various reasons that might require clearing up
4294 -- ??? For example, discriminant references that appear out of place, or
4295 -- spurious type errors with class-wide expressions. As a result, we
4296 -- limit the transformation to loop bounds, which is so far the only
4297 -- case that requires it.
4299 -----------------------------
4300 -- Safe_Prefixed_Reference --
4301 -----------------------------
4303 function Safe_Prefixed_Reference (N : Node_Id) return Boolean is
4305 -- If prefix is not side effect free, definitely not safe
4307 if not Side_Effect_Free (Prefix (N)) then
4310 -- If the prefix is of an access type that is not access-to-constant,
4311 -- then this construct is a variable reference, which means it is to
4312 -- be considered to have side effects if Variable_Ref is set True
4313 -- Exception is an access to an entity that is a constant or an
4314 -- in-parameter which does not come from source, and is the result
4315 -- of a previous removal of side-effects.
4317 elsif Is_Access_Type (Etype (Prefix (N)))
4318 and then not Is_Access_Constant (Etype (Prefix (N)))
4319 and then Variable_Ref
4321 if not Is_Entity_Name (Prefix (N)) then
4324 return Ekind (Entity (Prefix (N))) = E_Constant
4325 or else Ekind (Entity (Prefix (N))) = E_In_Parameter;
4328 -- The following test is the simplest way of solving a complex
4329 -- problem uncovered by BB08-010: Side effect on loop bound that
4330 -- is a subcomponent of a global variable:
4331 -- If a loop bound is a subcomponent of a global variable, a
4332 -- modification of that variable within the loop may incorrectly
4333 -- affect the execution of the loop.
4336 (Nkind (Parent (Parent (N))) /= N_Loop_Parameter_Specification
4337 or else not Within_In_Parameter (Prefix (N)))
4341 -- All other cases are side effect free
4346 end Safe_Prefixed_Reference;
4348 ----------------------
4349 -- Side_Effect_Free --
4350 ----------------------
4352 function Side_Effect_Free (N : Node_Id) return Boolean is
4354 -- Note on checks that could raise Constraint_Error. Strictly, if
4355 -- we take advantage of 11.6, these checks do not count as side
4356 -- effects. However, we would just as soon consider that they are
4357 -- side effects, since the backend CSE does not work very well on
4358 -- expressions which can raise Constraint_Error. On the other
4359 -- hand, if we do not consider them to be side effect free, then
4360 -- we get some awkward expansions in -gnato mode, resulting in
4361 -- code insertions at a point where we do not have a clear model
4362 -- for performing the insertions.
4364 -- Special handling for entity names
4366 if Is_Entity_Name (N) then
4368 -- If the entity is a constant, it is definitely side effect
4369 -- free. Note that the test of Is_Variable (N) below might
4370 -- be expected to catch this case, but it does not, because
4371 -- this test goes to the original tree, and we may have
4372 -- already rewritten a variable node with a constant as
4373 -- a result of an earlier Force_Evaluation call.
4375 if Ekind (Entity (N)) = E_Constant
4376 or else Ekind (Entity (N)) = E_In_Parameter
4380 -- Functions are not side effect free
4382 elsif Ekind (Entity (N)) = E_Function then
4385 -- Variables are considered to be a side effect if Variable_Ref
4386 -- is set or if we have a volatile reference and Name_Req is off.
4387 -- If Name_Req is True then we can't help returning a name which
4388 -- effectively allows multiple references in any case.
4390 elsif Is_Variable (N) then
4391 return not Variable_Ref
4392 and then (not Is_Volatile_Reference (N) or else Name_Req);
4394 -- Any other entity (e.g. a subtype name) is definitely side
4401 -- A value known at compile time is always side effect free
4403 elsif Compile_Time_Known_Value (N) then
4406 -- A variable renaming is not side-effect free, because the
4407 -- renaming will function like a macro in the front-end in
4408 -- some cases, and an assignment can modify the component
4409 -- designated by N, so we need to create a temporary for it.
4411 elsif Is_Entity_Name (Original_Node (N))
4412 and then Is_Renaming_Of_Object (Entity (Original_Node (N)))
4413 and then Ekind (Entity (Original_Node (N))) /= E_Constant
4418 -- For other than entity names and compile time known values,
4419 -- check the node kind for special processing.
4423 -- An attribute reference is side effect free if its expressions
4424 -- are side effect free and its prefix is side effect free or
4425 -- is an entity reference.
4427 -- Is this right? what about x'first where x is a variable???
4429 when N_Attribute_Reference =>
4430 return Side_Effect_Free (Expressions (N))
4431 and then Attribute_Name (N) /= Name_Input
4432 and then (Is_Entity_Name (Prefix (N))
4433 or else Side_Effect_Free (Prefix (N)));
4435 -- A binary operator is side effect free if and both operands
4436 -- are side effect free. For this purpose binary operators
4437 -- include membership tests and short circuit forms
4439 when N_Binary_Op | N_Membership_Test | N_Short_Circuit =>
4440 return Side_Effect_Free (Left_Opnd (N))
4442 Side_Effect_Free (Right_Opnd (N));
4444 -- An explicit dereference is side effect free only if it is
4445 -- a side effect free prefixed reference.
4447 when N_Explicit_Dereference =>
4448 return Safe_Prefixed_Reference (N);
4450 -- A call to _rep_to_pos is side effect free, since we generate
4451 -- this pure function call ourselves. Moreover it is critically
4452 -- important to make this exception, since otherwise we can
4453 -- have discriminants in array components which don't look
4454 -- side effect free in the case of an array whose index type
4455 -- is an enumeration type with an enumeration rep clause.
4457 -- All other function calls are not side effect free
4459 when N_Function_Call =>
4460 return Nkind (Name (N)) = N_Identifier
4461 and then Is_TSS (Name (N), TSS_Rep_To_Pos)
4463 Side_Effect_Free (First (Parameter_Associations (N)));
4465 -- An indexed component is side effect free if it is a side
4466 -- effect free prefixed reference and all the indexing
4467 -- expressions are side effect free.
4469 when N_Indexed_Component =>
4470 return Side_Effect_Free (Expressions (N))
4471 and then Safe_Prefixed_Reference (N);
4473 -- A type qualification is side effect free if the expression
4474 -- is side effect free.
4476 when N_Qualified_Expression =>
4477 return Side_Effect_Free (Expression (N));
4479 -- A selected component is side effect free only if it is a
4480 -- side effect free prefixed reference. If it designates a
4481 -- component with a rep. clause it must be treated has having
4482 -- a potential side effect, because it may be modified through
4483 -- a renaming, and a subsequent use of the renaming as a macro
4484 -- will yield the wrong value. This complex interaction between
4485 -- renaming and removing side effects is a reminder that the
4486 -- latter has become a headache to maintain, and that it should
4487 -- be removed in favor of the gcc mechanism to capture values ???
4489 when N_Selected_Component =>
4490 if Nkind (Parent (N)) = N_Explicit_Dereference
4491 and then Has_Non_Standard_Rep (Designated_Type (Etype (N)))
4495 return Safe_Prefixed_Reference (N);
4498 -- A range is side effect free if the bounds are side effect free
4501 return Side_Effect_Free (Low_Bound (N))
4502 and then Side_Effect_Free (High_Bound (N));
4504 -- A slice is side effect free if it is a side effect free
4505 -- prefixed reference and the bounds are side effect free.
4508 return Side_Effect_Free (Discrete_Range (N))
4509 and then Safe_Prefixed_Reference (N);
4511 -- A type conversion is side effect free if the expression to be
4512 -- converted is side effect free.
4514 when N_Type_Conversion =>
4515 return Side_Effect_Free (Expression (N));
4517 -- A unary operator is side effect free if the operand
4518 -- is side effect free.
4521 return Side_Effect_Free (Right_Opnd (N));
4523 -- An unchecked type conversion is side effect free only if it
4524 -- is safe and its argument is side effect free.
4526 when N_Unchecked_Type_Conversion =>
4527 return Safe_Unchecked_Type_Conversion (N)
4528 and then Side_Effect_Free (Expression (N));
4530 -- An unchecked expression is side effect free if its expression
4531 -- is side effect free.
4533 when N_Unchecked_Expression =>
4534 return Side_Effect_Free (Expression (N));
4536 -- A literal is side effect free
4538 when N_Character_Literal |
4544 -- We consider that anything else has side effects. This is a bit
4545 -- crude, but we are pretty close for most common cases, and we
4546 -- are certainly correct (i.e. we never return True when the
4547 -- answer should be False).
4552 end Side_Effect_Free;
4554 -- A list is side effect free if all elements of the list are
4555 -- side effect free.
4557 function Side_Effect_Free (L : List_Id) return Boolean is
4561 if L = No_List or else L = Error_List then
4566 while Present (N) loop
4567 if not Side_Effect_Free (N) then
4576 end Side_Effect_Free;
4578 -------------------------
4579 -- Within_In_Parameter --
4580 -------------------------
4582 function Within_In_Parameter (N : Node_Id) return Boolean is
4584 if not Comes_From_Source (N) then
4587 elsif Is_Entity_Name (N) then
4588 return Ekind (Entity (N)) = E_In_Parameter;
4590 elsif Nkind (N) = N_Indexed_Component
4591 or else Nkind (N) = N_Selected_Component
4593 return Within_In_Parameter (Prefix (N));
4598 end Within_In_Parameter;
4600 -- Start of processing for Remove_Side_Effects
4603 -- If we are side effect free already or expansion is disabled,
4604 -- there is nothing to do.
4606 if Side_Effect_Free (Exp) or else not Expander_Active then
4610 -- All this must not have any checks
4612 Scope_Suppress := (others => True);
4614 -- If it is a scalar type and we need to capture the value, just make
4615 -- a copy. Likewise for a function call, an attribute reference or an
4616 -- operator. And if we have a volatile reference and Name_Req is not
4617 -- set (see comments above for Side_Effect_Free).
4619 if Is_Elementary_Type (Exp_Type)
4620 and then (Variable_Ref
4621 or else Nkind (Exp) = N_Function_Call
4622 or else Nkind (Exp) = N_Attribute_Reference
4623 or else Nkind (Exp) in N_Op
4624 or else (not Name_Req and then Is_Volatile_Reference (Exp)))
4626 Def_Id := Make_Temporary (Loc, 'R', Exp);
4627 Set_Etype (Def_Id, Exp_Type);
4628 Res := New_Reference_To (Def_Id, Loc);
4631 Make_Object_Declaration (Loc,
4632 Defining_Identifier => Def_Id,
4633 Object_Definition => New_Reference_To (Exp_Type, Loc),
4634 Constant_Present => True,
4635 Expression => Relocate_Node (Exp));
4637 Set_Assignment_OK (E);
4638 Insert_Action (Exp, E);
4640 -- If the expression has the form v.all then we can just capture
4641 -- the pointer, and then do an explicit dereference on the result.
4643 elsif Nkind (Exp) = N_Explicit_Dereference then
4644 Def_Id := Make_Temporary (Loc, 'R', Exp);
4646 Make_Explicit_Dereference (Loc, New_Reference_To (Def_Id, Loc));
4649 Make_Object_Declaration (Loc,
4650 Defining_Identifier => Def_Id,
4651 Object_Definition =>
4652 New_Reference_To (Etype (Prefix (Exp)), Loc),
4653 Constant_Present => True,
4654 Expression => Relocate_Node (Prefix (Exp))));
4656 -- Similar processing for an unchecked conversion of an expression
4657 -- of the form v.all, where we want the same kind of treatment.
4659 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
4660 and then Nkind (Expression (Exp)) = N_Explicit_Dereference
4662 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
4663 Scope_Suppress := Svg_Suppress;
4666 -- If this is a type conversion, leave the type conversion and remove
4667 -- the side effects in the expression. This is important in several
4668 -- circumstances: for change of representations, and also when this is
4669 -- a view conversion to a smaller object, where gigi can end up creating
4670 -- its own temporary of the wrong size.
4672 elsif Nkind (Exp) = N_Type_Conversion then
4673 Remove_Side_Effects (Expression (Exp), Name_Req, Variable_Ref);
4674 Scope_Suppress := Svg_Suppress;
4677 -- If this is an unchecked conversion that Gigi can't handle, make
4678 -- a copy or a use a renaming to capture the value.
4680 elsif Nkind (Exp) = N_Unchecked_Type_Conversion
4681 and then not Safe_Unchecked_Type_Conversion (Exp)
4683 if CW_Or_Has_Controlled_Part (Exp_Type) then
4685 -- Use a renaming to capture the expression, rather than create
4686 -- a controlled temporary.
4688 Def_Id := Make_Temporary (Loc, 'R', Exp);
4689 Res := New_Reference_To (Def_Id, Loc);
4692 Make_Object_Renaming_Declaration (Loc,
4693 Defining_Identifier => Def_Id,
4694 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
4695 Name => Relocate_Node (Exp)));
4698 Def_Id := Make_Temporary (Loc, 'R', Exp);
4699 Set_Etype (Def_Id, Exp_Type);
4700 Res := New_Reference_To (Def_Id, Loc);
4703 Make_Object_Declaration (Loc,
4704 Defining_Identifier => Def_Id,
4705 Object_Definition => New_Reference_To (Exp_Type, Loc),
4706 Constant_Present => not Is_Variable (Exp),
4707 Expression => Relocate_Node (Exp));
4709 Set_Assignment_OK (E);
4710 Insert_Action (Exp, E);
4713 -- For expressions that denote objects, we can use a renaming scheme.
4714 -- We skip using this if we have a volatile reference and we do not
4715 -- have Name_Req set true (see comments above for Side_Effect_Free).
4717 elsif Is_Object_Reference (Exp)
4718 and then Nkind (Exp) /= N_Function_Call
4719 and then (Name_Req or else not Is_Volatile_Reference (Exp))
4721 Def_Id := Make_Temporary (Loc, 'R', Exp);
4723 if Nkind (Exp) = N_Selected_Component
4724 and then Nkind (Prefix (Exp)) = N_Function_Call
4725 and then Is_Array_Type (Exp_Type)
4727 -- Avoid generating a variable-sized temporary, by generating
4728 -- the renaming declaration just for the function call. The
4729 -- transformation could be refined to apply only when the array
4730 -- component is constrained by a discriminant???
4733 Make_Selected_Component (Loc,
4734 Prefix => New_Occurrence_Of (Def_Id, Loc),
4735 Selector_Name => Selector_Name (Exp));
4738 Make_Object_Renaming_Declaration (Loc,
4739 Defining_Identifier => Def_Id,
4741 New_Reference_To (Base_Type (Etype (Prefix (Exp))), Loc),
4742 Name => Relocate_Node (Prefix (Exp))));
4745 Res := New_Reference_To (Def_Id, Loc);
4748 Make_Object_Renaming_Declaration (Loc,
4749 Defining_Identifier => Def_Id,
4750 Subtype_Mark => New_Reference_To (Exp_Type, Loc),
4751 Name => Relocate_Node (Exp)));
4754 -- If this is a packed reference, or a selected component with a
4755 -- non-standard representation, a reference to the temporary will
4756 -- be replaced by a copy of the original expression (see
4757 -- Exp_Ch2.Expand_Renaming). Otherwise the temporary must be
4758 -- elaborated by gigi, and is of course not to be replaced in-line
4759 -- by the expression it renames, which would defeat the purpose of
4760 -- removing the side-effect.
4762 if (Nkind (Exp) = N_Selected_Component
4763 or else Nkind (Exp) = N_Indexed_Component)
4764 and then Has_Non_Standard_Rep (Etype (Prefix (Exp)))
4768 Set_Is_Renaming_Of_Object (Def_Id, False);
4771 -- Otherwise we generate a reference to the value
4774 -- Special processing for function calls that return a limited type.
4775 -- We need to build a declaration that will enable build-in-place
4776 -- expansion of the call. This is not done if the context is already
4777 -- an object declaration, to prevent infinite recursion.
4779 -- This is relevant only in Ada 2005 mode. In Ada 95 programs we have
4780 -- to accommodate functions returning limited objects by reference.
4782 if Nkind (Exp) = N_Function_Call
4783 and then Is_Inherently_Limited_Type (Etype (Exp))
4784 and then Nkind (Parent (Exp)) /= N_Object_Declaration
4785 and then Ada_Version >= Ada_05
4788 Obj : constant Entity_Id := Make_Temporary (Loc, 'F', Exp);
4793 Make_Object_Declaration (Loc,
4794 Defining_Identifier => Obj,
4795 Object_Definition => New_Occurrence_Of (Exp_Type, Loc),
4796 Expression => Relocate_Node (Exp));
4797 Insert_Action (Exp, Decl);
4798 Set_Etype (Obj, Exp_Type);
4799 Rewrite (Exp, New_Occurrence_Of (Obj, Loc));
4804 Ref_Type := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4807 Make_Full_Type_Declaration (Loc,
4808 Defining_Identifier => Ref_Type,
4810 Make_Access_To_Object_Definition (Loc,
4811 All_Present => True,
4812 Subtype_Indication =>
4813 New_Reference_To (Exp_Type, Loc)));
4816 Insert_Action (Exp, Ptr_Typ_Decl);
4818 Def_Id := Make_Temporary (Loc, 'R', Exp);
4819 Set_Etype (Def_Id, Exp_Type);
4822 Make_Explicit_Dereference (Loc,
4823 Prefix => New_Reference_To (Def_Id, Loc));
4825 if Nkind (E) = N_Explicit_Dereference then
4826 New_Exp := Relocate_Node (Prefix (E));
4828 E := Relocate_Node (E);
4829 New_Exp := Make_Reference (Loc, E);
4832 if Is_Delayed_Aggregate (E) then
4834 -- The expansion of nested aggregates is delayed until the
4835 -- enclosing aggregate is expanded. As aggregates are often
4836 -- qualified, the predicate applies to qualified expressions
4837 -- as well, indicating that the enclosing aggregate has not
4838 -- been expanded yet. At this point the aggregate is part of
4839 -- a stand-alone declaration, and must be fully expanded.
4841 if Nkind (E) = N_Qualified_Expression then
4842 Set_Expansion_Delayed (Expression (E), False);
4843 Set_Analyzed (Expression (E), False);
4845 Set_Expansion_Delayed (E, False);
4848 Set_Analyzed (E, False);
4852 Make_Object_Declaration (Loc,
4853 Defining_Identifier => Def_Id,
4854 Object_Definition => New_Reference_To (Ref_Type, Loc),
4855 Expression => New_Exp));
4858 -- Preserve the Assignment_OK flag in all copies, since at least
4859 -- one copy may be used in a context where this flag must be set
4860 -- (otherwise why would the flag be set in the first place).
4862 Set_Assignment_OK (Res, Assignment_OK (Exp));
4864 -- Finally rewrite the original expression and we are done
4867 Analyze_And_Resolve (Exp, Exp_Type);
4868 Scope_Suppress := Svg_Suppress;
4869 end Remove_Side_Effects;
4871 ---------------------------
4872 -- Represented_As_Scalar --
4873 ---------------------------
4875 function Represented_As_Scalar (T : Entity_Id) return Boolean is
4876 UT : constant Entity_Id := Underlying_Type (T);
4878 return Is_Scalar_Type (UT)
4879 or else (Is_Bit_Packed_Array (UT)
4880 and then Is_Scalar_Type (Packed_Array_Type (UT)));
4881 end Represented_As_Scalar;
4883 ------------------------------------
4884 -- Safe_Unchecked_Type_Conversion --
4885 ------------------------------------
4887 -- Note: this function knows quite a bit about the exact requirements
4888 -- of Gigi with respect to unchecked type conversions, and its code
4889 -- must be coordinated with any changes in Gigi in this area.
4891 -- The above requirements should be documented in Sinfo ???
4893 function Safe_Unchecked_Type_Conversion (Exp : Node_Id) return Boolean is
4898 Pexp : constant Node_Id := Parent (Exp);
4901 -- If the expression is the RHS of an assignment or object declaration
4902 -- we are always OK because there will always be a target.
4904 -- Object renaming declarations, (generated for view conversions of
4905 -- actuals in inlined calls), like object declarations, provide an
4906 -- explicit type, and are safe as well.
4908 if (Nkind (Pexp) = N_Assignment_Statement
4909 and then Expression (Pexp) = Exp)
4910 or else Nkind (Pexp) = N_Object_Declaration
4911 or else Nkind (Pexp) = N_Object_Renaming_Declaration
4915 -- If the expression is the prefix of an N_Selected_Component
4916 -- we should also be OK because GCC knows to look inside the
4917 -- conversion except if the type is discriminated. We assume
4918 -- that we are OK anyway if the type is not set yet or if it is
4919 -- controlled since we can't afford to introduce a temporary in
4922 elsif Nkind (Pexp) = N_Selected_Component
4923 and then Prefix (Pexp) = Exp
4925 if No (Etype (Pexp)) then
4929 not Has_Discriminants (Etype (Pexp))
4930 or else Is_Constrained (Etype (Pexp));
4934 -- Set the output type, this comes from Etype if it is set, otherwise
4935 -- we take it from the subtype mark, which we assume was already
4938 if Present (Etype (Exp)) then
4939 Otyp := Etype (Exp);
4941 Otyp := Entity (Subtype_Mark (Exp));
4944 -- The input type always comes from the expression, and we assume
4945 -- this is indeed always analyzed, so we can simply get the Etype.
4947 Ityp := Etype (Expression (Exp));
4949 -- Initialize alignments to unknown so far
4954 -- Replace a concurrent type by its corresponding record type
4955 -- and each type by its underlying type and do the tests on those.
4956 -- The original type may be a private type whose completion is a
4957 -- concurrent type, so find the underlying type first.
4959 if Present (Underlying_Type (Otyp)) then
4960 Otyp := Underlying_Type (Otyp);
4963 if Present (Underlying_Type (Ityp)) then
4964 Ityp := Underlying_Type (Ityp);
4967 if Is_Concurrent_Type (Otyp) then
4968 Otyp := Corresponding_Record_Type (Otyp);
4971 if Is_Concurrent_Type (Ityp) then
4972 Ityp := Corresponding_Record_Type (Ityp);
4975 -- If the base types are the same, we know there is no problem since
4976 -- this conversion will be a noop.
4978 if Implementation_Base_Type (Otyp) = Implementation_Base_Type (Ityp) then
4981 -- Same if this is an upwards conversion of an untagged type, and there
4982 -- are no constraints involved (could be more general???)
4984 elsif Etype (Ityp) = Otyp
4985 and then not Is_Tagged_Type (Ityp)
4986 and then not Has_Discriminants (Ityp)
4987 and then No (First_Rep_Item (Base_Type (Ityp)))
4991 -- If the expression has an access type (object or subprogram) we
4992 -- assume that the conversion is safe, because the size of the target
4993 -- is safe, even if it is a record (which might be treated as having
4994 -- unknown size at this point).
4996 elsif Is_Access_Type (Ityp) then
4999 -- If the size of output type is known at compile time, there is
5000 -- never a problem. Note that unconstrained records are considered
5001 -- to be of known size, but we can't consider them that way here,
5002 -- because we are talking about the actual size of the object.
5004 -- We also make sure that in addition to the size being known, we do
5005 -- not have a case which might generate an embarrassingly large temp
5006 -- in stack checking mode.
5008 elsif Size_Known_At_Compile_Time (Otyp)
5010 (not Stack_Checking_Enabled
5011 or else not May_Generate_Large_Temp (Otyp))
5012 and then not (Is_Record_Type (Otyp) and then not Is_Constrained (Otyp))
5016 -- If either type is tagged, then we know the alignment is OK so
5017 -- Gigi will be able to use pointer punning.
5019 elsif Is_Tagged_Type (Otyp) or else Is_Tagged_Type (Ityp) then
5022 -- If either type is a limited record type, we cannot do a copy, so
5023 -- say safe since there's nothing else we can do.
5025 elsif Is_Limited_Record (Otyp) or else Is_Limited_Record (Ityp) then
5028 -- Conversions to and from packed array types are always ignored and
5031 elsif Is_Packed_Array_Type (Otyp)
5032 or else Is_Packed_Array_Type (Ityp)
5037 -- The only other cases known to be safe is if the input type's
5038 -- alignment is known to be at least the maximum alignment for the
5039 -- target or if both alignments are known and the output type's
5040 -- alignment is no stricter than the input's. We can use the alignment
5041 -- of the component type of an array if a type is an unpacked
5044 if Present (Alignment_Clause (Otyp)) then
5045 Oalign := Expr_Value (Expression (Alignment_Clause (Otyp)));
5047 elsif Is_Array_Type (Otyp)
5048 and then Present (Alignment_Clause (Component_Type (Otyp)))
5050 Oalign := Expr_Value (Expression (Alignment_Clause
5051 (Component_Type (Otyp))));
5054 if Present (Alignment_Clause (Ityp)) then
5055 Ialign := Expr_Value (Expression (Alignment_Clause (Ityp)));
5057 elsif Is_Array_Type (Ityp)
5058 and then Present (Alignment_Clause (Component_Type (Ityp)))
5060 Ialign := Expr_Value (Expression (Alignment_Clause
5061 (Component_Type (Ityp))));
5064 if Ialign /= No_Uint and then Ialign > Maximum_Alignment then
5067 elsif Ialign /= No_Uint and then Oalign /= No_Uint
5068 and then Ialign <= Oalign
5072 -- Otherwise, Gigi cannot handle this and we must make a temporary
5077 end Safe_Unchecked_Type_Conversion;
5079 ---------------------------------
5080 -- Set_Current_Value_Condition --
5081 ---------------------------------
5083 -- Note: the implementation of this procedure is very closely tied to the
5084 -- implementation of Get_Current_Value_Condition. Here we set required
5085 -- Current_Value fields, and in Get_Current_Value_Condition, we interpret
5086 -- them, so they must have a consistent view.
5088 procedure Set_Current_Value_Condition (Cnode : Node_Id) is
5090 procedure Set_Entity_Current_Value (N : Node_Id);
5091 -- If N is an entity reference, where the entity is of an appropriate
5092 -- kind, then set the current value of this entity to Cnode, unless
5093 -- there is already a definite value set there.
5095 procedure Set_Expression_Current_Value (N : Node_Id);
5096 -- If N is of an appropriate form, sets an appropriate entry in current
5097 -- value fields of relevant entities. Multiple entities can be affected
5098 -- in the case of an AND or AND THEN.
5100 ------------------------------
5101 -- Set_Entity_Current_Value --
5102 ------------------------------
5104 procedure Set_Entity_Current_Value (N : Node_Id) is
5106 if Is_Entity_Name (N) then
5108 Ent : constant Entity_Id := Entity (N);
5111 -- Don't capture if not safe to do so
5113 if not Safe_To_Capture_Value (N, Ent, Cond => True) then
5117 -- Here we have a case where the Current_Value field may
5118 -- need to be set. We set it if it is not already set to a
5119 -- compile time expression value.
5121 -- Note that this represents a decision that one condition
5122 -- blots out another previous one. That's certainly right
5123 -- if they occur at the same level. If the second one is
5124 -- nested, then the decision is neither right nor wrong (it
5125 -- would be equally OK to leave the outer one in place, or
5126 -- take the new inner one. Really we should record both, but
5127 -- our data structures are not that elaborate.
5129 if Nkind (Current_Value (Ent)) not in N_Subexpr then
5130 Set_Current_Value (Ent, Cnode);
5134 end Set_Entity_Current_Value;
5136 ----------------------------------
5137 -- Set_Expression_Current_Value --
5138 ----------------------------------
5140 procedure Set_Expression_Current_Value (N : Node_Id) is
5146 -- Loop to deal with (ignore for now) any NOT operators present. The
5147 -- presence of NOT operators will be handled properly when we call
5148 -- Get_Current_Value_Condition.
5150 while Nkind (Cond) = N_Op_Not loop
5151 Cond := Right_Opnd (Cond);
5154 -- For an AND or AND THEN, recursively process operands
5156 if Nkind (Cond) = N_Op_And or else Nkind (Cond) = N_And_Then then
5157 Set_Expression_Current_Value (Left_Opnd (Cond));
5158 Set_Expression_Current_Value (Right_Opnd (Cond));
5162 -- Check possible relational operator
5164 if Nkind (Cond) in N_Op_Compare then
5165 if Compile_Time_Known_Value (Right_Opnd (Cond)) then
5166 Set_Entity_Current_Value (Left_Opnd (Cond));
5167 elsif Compile_Time_Known_Value (Left_Opnd (Cond)) then
5168 Set_Entity_Current_Value (Right_Opnd (Cond));
5171 -- Check possible boolean variable reference
5174 Set_Entity_Current_Value (Cond);
5176 end Set_Expression_Current_Value;
5178 -- Start of processing for Set_Current_Value_Condition
5181 Set_Expression_Current_Value (Condition (Cnode));
5182 end Set_Current_Value_Condition;
5184 --------------------------
5185 -- Set_Elaboration_Flag --
5186 --------------------------
5188 procedure Set_Elaboration_Flag (N : Node_Id; Spec_Id : Entity_Id) is
5189 Loc : constant Source_Ptr := Sloc (N);
5190 Ent : constant Entity_Id := Elaboration_Entity (Spec_Id);
5194 if Present (Ent) then
5196 -- Nothing to do if at the compilation unit level, because in this
5197 -- case the flag is set by the binder generated elaboration routine.
5199 if Nkind (Parent (N)) = N_Compilation_Unit then
5202 -- Here we do need to generate an assignment statement
5205 Check_Restriction (No_Elaboration_Code, N);
5207 Make_Assignment_Statement (Loc,
5208 Name => New_Occurrence_Of (Ent, Loc),
5209 Expression => New_Occurrence_Of (Standard_True, Loc));
5211 if Nkind (Parent (N)) = N_Subunit then
5212 Insert_After (Corresponding_Stub (Parent (N)), Asn);
5214 Insert_After (N, Asn);
5219 -- Kill current value indication. This is necessary because the
5220 -- tests of this flag are inserted out of sequence and must not
5221 -- pick up bogus indications of the wrong constant value.
5223 Set_Current_Value (Ent, Empty);
5226 end Set_Elaboration_Flag;
5228 ----------------------------
5229 -- Set_Renamed_Subprogram --
5230 ----------------------------
5232 procedure Set_Renamed_Subprogram (N : Node_Id; E : Entity_Id) is
5234 -- If input node is an identifier, we can just reset it
5236 if Nkind (N) = N_Identifier then
5237 Set_Chars (N, Chars (E));
5240 -- Otherwise we have to do a rewrite, preserving Comes_From_Source
5244 CS : constant Boolean := Comes_From_Source (N);
5246 Rewrite (N, Make_Identifier (Sloc (N), Chars => Chars (E)));
5248 Set_Comes_From_Source (N, CS);
5249 Set_Analyzed (N, True);
5252 end Set_Renamed_Subprogram;
5254 ----------------------------------
5255 -- Silly_Boolean_Array_Not_Test --
5256 ----------------------------------
5258 -- This procedure implements an odd and silly test. We explicitly check
5259 -- for the case where the 'First of the component type is equal to the
5260 -- 'Last of this component type, and if this is the case, we make sure
5261 -- that constraint error is raised. The reason is that the NOT is bound
5262 -- to cause CE in this case, and we will not otherwise catch it.
5264 -- No such check is required for AND and OR, since for both these cases
5265 -- False op False = False, and True op True = True. For the XOR case,
5266 -- see Silly_Boolean_Array_Xor_Test.
5268 -- Believe it or not, this was reported as a bug. Note that nearly
5269 -- always, the test will evaluate statically to False, so the code will
5270 -- be statically removed, and no extra overhead caused.
5272 procedure Silly_Boolean_Array_Not_Test (N : Node_Id; T : Entity_Id) is
5273 Loc : constant Source_Ptr := Sloc (N);
5274 CT : constant Entity_Id := Component_Type (T);
5277 -- The check we install is
5279 -- constraint_error when
5280 -- component_type'first = component_type'last
5281 -- and then array_type'Length /= 0)
5283 -- We need the last guard because we don't want to raise CE for empty
5284 -- arrays since no out of range values result. (Empty arrays with a
5285 -- component type of True .. True -- very useful -- even the ACATS
5286 -- does not test that marginal case!)
5289 Make_Raise_Constraint_Error (Loc,
5295 Make_Attribute_Reference (Loc,
5296 Prefix => New_Occurrence_Of (CT, Loc),
5297 Attribute_Name => Name_First),
5300 Make_Attribute_Reference (Loc,
5301 Prefix => New_Occurrence_Of (CT, Loc),
5302 Attribute_Name => Name_Last)),
5304 Right_Opnd => Make_Non_Empty_Check (Loc, Right_Opnd (N))),
5305 Reason => CE_Range_Check_Failed));
5306 end Silly_Boolean_Array_Not_Test;
5308 ----------------------------------
5309 -- Silly_Boolean_Array_Xor_Test --
5310 ----------------------------------
5312 -- This procedure implements an odd and silly test. We explicitly check
5313 -- for the XOR case where the component type is True .. True, since this
5314 -- will raise constraint error. A special check is required since CE
5315 -- will not be generated otherwise (cf Expand_Packed_Not).
5317 -- No such check is required for AND and OR, since for both these cases
5318 -- False op False = False, and True op True = True, and no check is
5319 -- required for the case of False .. False, since False xor False = False.
5320 -- See also Silly_Boolean_Array_Not_Test
5322 procedure Silly_Boolean_Array_Xor_Test (N : Node_Id; T : Entity_Id) is
5323 Loc : constant Source_Ptr := Sloc (N);
5324 CT : constant Entity_Id := Component_Type (T);
5327 -- The check we install is
5329 -- constraint_error when
5330 -- Boolean (component_type'First)
5331 -- and then Boolean (component_type'Last)
5332 -- and then array_type'Length /= 0)
5334 -- We need the last guard because we don't want to raise CE for empty
5335 -- arrays since no out of range values result (Empty arrays with a
5336 -- component type of True .. True -- very useful -- even the ACATS
5337 -- does not test that marginal case!).
5340 Make_Raise_Constraint_Error (Loc,
5346 Convert_To (Standard_Boolean,
5347 Make_Attribute_Reference (Loc,
5348 Prefix => New_Occurrence_Of (CT, Loc),
5349 Attribute_Name => Name_First)),
5352 Convert_To (Standard_Boolean,
5353 Make_Attribute_Reference (Loc,
5354 Prefix => New_Occurrence_Of (CT, Loc),
5355 Attribute_Name => Name_Last))),
5357 Right_Opnd => Make_Non_Empty_Check (Loc, Right_Opnd (N))),
5358 Reason => CE_Range_Check_Failed));
5359 end Silly_Boolean_Array_Xor_Test;
5361 --------------------------
5362 -- Target_Has_Fixed_Ops --
5363 --------------------------
5365 Integer_Sized_Small : Ureal;
5366 -- Set to 2.0 ** -(Integer'Size - 1) the first time that this
5367 -- function is called (we don't want to compute it more than once!)
5369 Long_Integer_Sized_Small : Ureal;
5370 -- Set to 2.0 ** -(Long_Integer'Size - 1) the first time that this
5371 -- function is called (we don't want to compute it more than once)
5373 First_Time_For_THFO : Boolean := True;
5374 -- Set to False after first call (if Fractional_Fixed_Ops_On_Target)
5376 function Target_Has_Fixed_Ops
5377 (Left_Typ : Entity_Id;
5378 Right_Typ : Entity_Id;
5379 Result_Typ : Entity_Id) return Boolean
5381 function Is_Fractional_Type (Typ : Entity_Id) return Boolean;
5382 -- Return True if the given type is a fixed-point type with a small
5383 -- value equal to 2 ** (-(T'Object_Size - 1)) and whose values have
5384 -- an absolute value less than 1.0. This is currently limited
5385 -- to fixed-point types that map to Integer or Long_Integer.
5387 ------------------------
5388 -- Is_Fractional_Type --
5389 ------------------------
5391 function Is_Fractional_Type (Typ : Entity_Id) return Boolean is
5393 if Esize (Typ) = Standard_Integer_Size then
5394 return Small_Value (Typ) = Integer_Sized_Small;
5396 elsif Esize (Typ) = Standard_Long_Integer_Size then
5397 return Small_Value (Typ) = Long_Integer_Sized_Small;
5402 end Is_Fractional_Type;
5404 -- Start of processing for Target_Has_Fixed_Ops
5407 -- Return False if Fractional_Fixed_Ops_On_Target is false
5409 if not Fractional_Fixed_Ops_On_Target then
5413 -- Here the target has Fractional_Fixed_Ops, if first time, compute
5414 -- standard constants used by Is_Fractional_Type.
5416 if First_Time_For_THFO then
5417 First_Time_For_THFO := False;
5419 Integer_Sized_Small :=
5422 Den => UI_From_Int (Standard_Integer_Size - 1),
5425 Long_Integer_Sized_Small :=
5428 Den => UI_From_Int (Standard_Long_Integer_Size - 1),
5432 -- Return True if target supports fixed-by-fixed multiply/divide
5433 -- for fractional fixed-point types (see Is_Fractional_Type) and
5434 -- the operand and result types are equivalent fractional types.
5436 return Is_Fractional_Type (Base_Type (Left_Typ))
5437 and then Is_Fractional_Type (Base_Type (Right_Typ))
5438 and then Is_Fractional_Type (Base_Type (Result_Typ))
5439 and then Esize (Left_Typ) = Esize (Right_Typ)
5440 and then Esize (Left_Typ) = Esize (Result_Typ);
5441 end Target_Has_Fixed_Ops;
5443 ------------------------------------------
5444 -- Type_May_Have_Bit_Aligned_Components --
5445 ------------------------------------------
5447 function Type_May_Have_Bit_Aligned_Components
5448 (Typ : Entity_Id) return Boolean
5451 -- Array type, check component type
5453 if Is_Array_Type (Typ) then
5455 Type_May_Have_Bit_Aligned_Components (Component_Type (Typ));
5457 -- Record type, check components
5459 elsif Is_Record_Type (Typ) then
5464 E := First_Component_Or_Discriminant (Typ);
5465 while Present (E) loop
5466 if Component_May_Be_Bit_Aligned (E)
5467 or else Type_May_Have_Bit_Aligned_Components (Etype (E))
5472 Next_Component_Or_Discriminant (E);
5478 -- Type other than array or record is always OK
5483 end Type_May_Have_Bit_Aligned_Components;
5485 ----------------------------
5486 -- Wrap_Cleanup_Procedure --
5487 ----------------------------
5489 procedure Wrap_Cleanup_Procedure (N : Node_Id) is
5490 Loc : constant Source_Ptr := Sloc (N);
5491 Stseq : constant Node_Id := Handled_Statement_Sequence (N);
5492 Stmts : constant List_Id := Statements (Stseq);
5495 if Abort_Allowed then
5496 Prepend_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Defer));
5497 Append_To (Stmts, Build_Runtime_Call (Loc, RE_Abort_Undefer));
5499 end Wrap_Cleanup_Procedure;