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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P _ A G G R --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2005 Free Software Foundation, Inc. --
10 -- --
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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
21 -- --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 -- --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Expander; use Expander;
33 with Exp_Util; use Exp_Util;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch7; use Exp_Ch7;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Tss; use Exp_Tss;
38 with Freeze; use Freeze;
39 with Hostparm; use Hostparm;
40 with Itypes; use Itypes;
41 with Lib; use Lib;
42 with Nmake; use Nmake;
43 with Nlists; use Nlists;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
46 with Rtsfind; use Rtsfind;
47 with Ttypes; use Ttypes;
48 with Sem; use Sem;
49 with Sem_Ch3; use Sem_Ch3;
50 with Sem_Eval; use Sem_Eval;
51 with Sem_Res; use Sem_Res;
52 with Sem_Util; use Sem_Util;
53 with Sinfo; use Sinfo;
54 with Snames; use Snames;
55 with Stand; use Stand;
56 with Tbuild; use Tbuild;
57 with Uintp; use Uintp;
59 package body Exp_Aggr is
61 type Case_Bounds is record
62 Choice_Lo : Node_Id;
63 Choice_Hi : Node_Id;
64 Choice_Node : Node_Id;
65 end record;
67 type Case_Table_Type is array (Nat range <>) of Case_Bounds;
68 -- Table type used by Check_Case_Choices procedure
70 function Must_Slide
71 (Obj_Type : Entity_Id;
72 Typ : Entity_Id) return Boolean;
73 -- A static array aggregate in an object declaration can in most cases be
74 -- expanded in place. The one exception is when the aggregate is given
75 -- with component associations that specify different bounds from those of
76 -- the type definition in the object declaration. In this pathological
77 -- case the aggregate must slide, and we must introduce an intermediate
78 -- temporary to hold it.
80 -- The same holds in an assignment to one-dimensional array of arrays,
81 -- when a component may be given with bounds that differ from those of the
82 -- component type.
84 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
85 -- Sort the Case Table using the Lower Bound of each Choice as the key.
86 -- A simple insertion sort is used since the number of choices in a case
87 -- statement of variant part will usually be small and probably in near
88 -- sorted order.
90 function Has_Default_Init_Comps (N : Node_Id) return Boolean;
91 -- N is an aggregate (record or array). Checks the presence of default
92 -- initialization (<>) in any component (Ada 2005: AI-287)
94 ------------------------------------------------------
95 -- Local subprograms for Record Aggregate Expansion --
96 ------------------------------------------------------
98 procedure Expand_Record_Aggregate
99 (N : Node_Id;
100 Orig_Tag : Node_Id := Empty;
101 Parent_Expr : Node_Id := Empty);
102 -- This is the top level procedure for record aggregate expansion.
103 -- Expansion for record aggregates needs expand aggregates for tagged
104 -- record types. Specifically Expand_Record_Aggregate adds the Tag
105 -- field in front of the Component_Association list that was created
106 -- during resolution by Resolve_Record_Aggregate.
108 -- N is the record aggregate node.
109 -- Orig_Tag is the value of the Tag that has to be provided for this
110 -- specific aggregate. It carries the tag corresponding to the type
111 -- of the outermost aggregate during the recursive expansion
112 -- Parent_Expr is the ancestor part of the original extension
113 -- aggregate
115 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id);
116 -- N is an N_Aggregate of a N_Extension_Aggregate. Typ is the type of
117 -- the aggregate. Transform the given aggregate into a sequence of
118 -- assignments component per component.
120 function Build_Record_Aggr_Code
121 (N : Node_Id;
122 Typ : Entity_Id;
123 Target : Node_Id;
124 Flist : Node_Id := Empty;
125 Obj : Entity_Id := Empty;
126 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id;
127 -- N is an N_Aggregate or a N_Extension_Aggregate. Typ is the type of the
128 -- aggregate. Target is an expression containing the location on which the
129 -- component by component assignments will take place. Returns the list of
130 -- assignments plus all other adjustments needed for tagged and controlled
131 -- types. Flist is an expression representing the finalization list on
132 -- which to attach the controlled components if any. Obj is present in the
133 -- object declaration and dynamic allocation cases, it contains an entity
134 -- that allows to know if the value being created needs to be attached to
135 -- the final list in case of pragma finalize_Storage_Only.
137 -- Is_Limited_Ancestor_Expansion indicates that the function has been
138 -- called recursively to expand the limited ancestor to avoid copying it.
140 function Has_Mutable_Components (Typ : Entity_Id) return Boolean;
141 -- Return true if one of the component is of a discriminated type with
142 -- defaults. An aggregate for a type with mutable components must be
143 -- expanded into individual assignments.
145 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id);
146 -- If the type of the aggregate is a type extension with renamed discrimi-
147 -- nants, we must initialize the hidden discriminants of the parent.
148 -- Otherwise, the target object must not be initialized. The discriminants
149 -- are initialized by calling the initialization procedure for the type.
150 -- This is incorrect if the initialization of other components has any
151 -- side effects. We restrict this call to the case where the parent type
152 -- has a variant part, because this is the only case where the hidden
153 -- discriminants are accessed, namely when calling discriminant checking
154 -- functions of the parent type, and when applying a stream attribute to
155 -- an object of the derived type.
157 -----------------------------------------------------
158 -- Local Subprograms for Array Aggregate Expansion --
159 -----------------------------------------------------
161 procedure Convert_Array_Aggr_In_Allocator
162 (Decl : Node_Id;
163 Aggr : Node_Id;
164 Target : Node_Id);
165 -- If the aggregate appears within an allocator and can be expanded in
166 -- place, this routine generates the individual assignments to components
167 -- of the designated object. This is an optimization over the general
168 -- case, where a temporary is first created on the stack and then used to
169 -- construct the allocated object on the heap.
171 procedure Convert_To_Positional
172 (N : Node_Id;
173 Max_Others_Replicate : Nat := 5;
174 Handle_Bit_Packed : Boolean := False);
175 -- If possible, convert named notation to positional notation. This
176 -- conversion is possible only in some static cases. If the conversion is
177 -- possible, then N is rewritten with the analyzed converted aggregate.
178 -- The parameter Max_Others_Replicate controls the maximum number of
179 -- values corresponding to an others choice that will be converted to
180 -- positional notation (the default of 5 is the normal limit, and reflects
181 -- the fact that normally the loop is better than a lot of separate
182 -- assignments). Note that this limit gets overridden in any case if
183 -- either of the restrictions No_Elaboration_Code or No_Implicit_Loops is
184 -- set. The parameter Handle_Bit_Packed is usually set False (since we do
185 -- not expect the back end to handle bit packed arrays, so the normal case
186 -- of conversion is pointless), but in the special case of a call from
187 -- Packed_Array_Aggregate_Handled, we set this parameter to True, since
188 -- these are cases we handle in there.
190 procedure Expand_Array_Aggregate (N : Node_Id);
191 -- This is the top-level routine to perform array aggregate expansion.
192 -- N is the N_Aggregate node to be expanded.
194 function Backend_Processing_Possible (N : Node_Id) return Boolean;
195 -- This function checks if array aggregate N can be processed directly
196 -- by Gigi. If this is the case True is returned.
198 function Build_Array_Aggr_Code
199 (N : Node_Id;
200 Ctype : Entity_Id;
201 Index : Node_Id;
202 Into : Node_Id;
203 Scalar_Comp : Boolean;
204 Indices : List_Id := No_List;
205 Flist : Node_Id := Empty) return List_Id;
206 -- This recursive routine returns a list of statements containing the
207 -- loops and assignments that are needed for the expansion of the array
208 -- aggregate N.
210 -- N is the (sub-)aggregate node to be expanded into code. This node
211 -- has been fully analyzed, and its Etype is properly set.
213 -- Index is the index node corresponding to the array sub-aggregate N.
215 -- Into is the target expression into which we are copying the aggregate.
216 -- Note that this node may not have been analyzed yet, and so the Etype
217 -- field may not be set.
219 -- Scalar_Comp is True if the component type of the aggregate is scalar.
221 -- Indices is the current list of expressions used to index the
222 -- object we are writing into.
224 -- Flist is an expression representing the finalization list on which
225 -- to attach the controlled components if any.
227 function Number_Of_Choices (N : Node_Id) return Nat;
228 -- Returns the number of discrete choices (not including the others choice
229 -- if present) contained in (sub-)aggregate N.
231 function Late_Expansion
232 (N : Node_Id;
233 Typ : Entity_Id;
234 Target : Node_Id;
235 Flist : Node_Id := Empty;
236 Obj : Entity_Id := Empty) return List_Id;
237 -- N is a nested (record or array) aggregate that has been marked with
238 -- 'Delay_Expansion'. Typ is the expected type of the aggregate and Target
239 -- is a (duplicable) expression that will hold the result of the aggregate
240 -- expansion. Flist is the finalization list to be used to attach
241 -- controlled components. 'Obj' when non empty, carries the original
242 -- object being initialized in order to know if it needs to be attached to
243 -- the previous parameter which may not be the case in the case where
244 -- Finalize_Storage_Only is set. Basically this procedure is used to
245 -- implement top-down expansions of nested aggregates. This is necessary
246 -- for avoiding temporaries at each level as well as for propagating the
247 -- right internal finalization list.
249 function Make_OK_Assignment_Statement
250 (Sloc : Source_Ptr;
251 Name : Node_Id;
252 Expression : Node_Id) return Node_Id;
253 -- This is like Make_Assignment_Statement, except that Assignment_OK
254 -- is set in the left operand. All assignments built by this unit
255 -- use this routine. This is needed to deal with assignments to
256 -- initialized constants that are done in place.
258 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean;
259 -- Given an array aggregate, this function handles the case of a packed
260 -- array aggregate with all constant values, where the aggregate can be
261 -- evaluated at compile time. If this is possible, then N is rewritten
262 -- to be its proper compile time value with all the components properly
263 -- assembled. The expression is analyzed and resolved and True is
264 -- returned. If this transformation is not possible, N is unchanged
265 -- and False is returned
267 function Safe_Slice_Assignment (N : Node_Id) return Boolean;
268 -- If a slice assignment has an aggregate with a single others_choice,
269 -- the assignment can be done in place even if bounds are not static,
270 -- by converting it into a loop over the discrete range of the slice.
272 ---------------------------------
273 -- Backend_Processing_Possible --
274 ---------------------------------
276 -- Backend processing by Gigi/gcc is possible only if all the following
277 -- conditions are met:
279 -- 1. N is fully positional
281 -- 2. N is not a bit-packed array aggregate;
283 -- 3. The size of N's array type must be known at compile time. Note
284 -- that this implies that the component size is also known
286 -- 4. The array type of N does not follow the Fortran layout convention
287 -- or if it does it must be 1 dimensional.
289 -- 5. The array component type is tagged, which may necessitate
290 -- reassignment of proper tags.
292 -- 6. The array component type might have unaligned bit components
294 function Backend_Processing_Possible (N : Node_Id) return Boolean is
295 Typ : constant Entity_Id := Etype (N);
296 -- Typ is the correct constrained array subtype of the aggregate
298 function Static_Check (N : Node_Id; Index : Node_Id) return Boolean;
299 -- Recursively checks that N is fully positional, returns true if so
301 ------------------
302 -- Static_Check --
303 ------------------
305 function Static_Check (N : Node_Id; Index : Node_Id) return Boolean is
306 Expr : Node_Id;
308 begin
309 -- Check for component associations
311 if Present (Component_Associations (N)) then
312 return False;
313 end if;
315 -- Recurse to check subaggregates, which may appear in qualified
316 -- expressions. If delayed, the front-end will have to expand.
318 Expr := First (Expressions (N));
320 while Present (Expr) loop
322 if Is_Delayed_Aggregate (Expr) then
323 return False;
324 end if;
326 if Present (Next_Index (Index))
327 and then not Static_Check (Expr, Next_Index (Index))
328 then
329 return False;
330 end if;
332 Next (Expr);
333 end loop;
335 return True;
336 end Static_Check;
338 -- Start of processing for Backend_Processing_Possible
340 begin
341 -- Checks 2 (array must not be bit packed)
343 if Is_Bit_Packed_Array (Typ) then
344 return False;
345 end if;
347 -- Checks 4 (array must not be multi-dimensional Fortran case)
349 if Convention (Typ) = Convention_Fortran
350 and then Number_Dimensions (Typ) > 1
351 then
352 return False;
353 end if;
355 -- Checks 3 (size of array must be known at compile time)
357 if not Size_Known_At_Compile_Time (Typ) then
358 return False;
359 end if;
361 -- Checks 1 (aggregate must be fully positional)
363 if not Static_Check (N, First_Index (Typ)) then
364 return False;
365 end if;
367 -- Checks 5 (if the component type is tagged, then we may need
368 -- to do tag adjustments; perhaps this should be refined to check for
369 -- any component associations that actually need tag adjustment,
370 -- along the lines of the test that is carried out in
371 -- Has_Delayed_Nested_Aggregate_Or_Tagged_Comps for record aggregates
372 -- with tagged components, but not clear whether it's worthwhile ???;
373 -- in the case of the JVM, object tags are handled implicitly)
375 if Is_Tagged_Type (Component_Type (Typ)) and then not Java_VM then
376 return False;
377 end if;
379 -- Checks 6 (component type must not have bit aligned components)
381 if Type_May_Have_Bit_Aligned_Components (Component_Type (Typ)) then
382 return False;
383 end if;
385 -- Backend processing is possible
387 Set_Compile_Time_Known_Aggregate (N, True);
388 Set_Size_Known_At_Compile_Time (Etype (N), True);
389 return True;
390 end Backend_Processing_Possible;
392 ---------------------------
393 -- Build_Array_Aggr_Code --
394 ---------------------------
396 -- The code that we generate from a one dimensional aggregate is
398 -- 1. If the sub-aggregate contains discrete choices we
400 -- (a) Sort the discrete choices
402 -- (b) Otherwise for each discrete choice that specifies a range we
403 -- emit a loop. If a range specifies a maximum of three values, or
404 -- we are dealing with an expression we emit a sequence of
405 -- assignments instead of a loop.
407 -- (c) Generate the remaining loops to cover the others choice if any
409 -- 2. If the aggregate contains positional elements we
411 -- (a) translate the positional elements in a series of assignments
413 -- (b) Generate a final loop to cover the others choice if any.
414 -- Note that this final loop has to be a while loop since the case
416 -- L : Integer := Integer'Last;
417 -- H : Integer := Integer'Last;
418 -- A : array (L .. H) := (1, others =>0);
420 -- cannot be handled by a for loop. Thus for the following
422 -- array (L .. H) := (.. positional elements.., others =>E);
424 -- we always generate something like:
426 -- J : Index_Type := Index_Of_Last_Positional_Element;
427 -- while J < H loop
428 -- J := Index_Base'Succ (J)
429 -- Tmp (J) := E;
430 -- end loop;
432 function Build_Array_Aggr_Code
433 (N : Node_Id;
434 Ctype : Entity_Id;
435 Index : Node_Id;
436 Into : Node_Id;
437 Scalar_Comp : Boolean;
438 Indices : List_Id := No_List;
439 Flist : Node_Id := Empty) return List_Id
441 Loc : constant Source_Ptr := Sloc (N);
442 Index_Base : constant Entity_Id := Base_Type (Etype (Index));
443 Index_Base_L : constant Node_Id := Type_Low_Bound (Index_Base);
444 Index_Base_H : constant Node_Id := Type_High_Bound (Index_Base);
446 function Add (Val : Int; To : Node_Id) return Node_Id;
447 -- Returns an expression where Val is added to expression To, unless
448 -- To+Val is provably out of To's base type range. To must be an
449 -- already analyzed expression.
451 function Empty_Range (L, H : Node_Id) return Boolean;
452 -- Returns True if the range defined by L .. H is certainly empty
454 function Equal (L, H : Node_Id) return Boolean;
455 -- Returns True if L = H for sure
457 function Index_Base_Name return Node_Id;
458 -- Returns a new reference to the index type name
460 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id;
461 -- Ind must be a side-effect free expression. If the input aggregate
462 -- N to Build_Loop contains no sub-aggregates, then this function
463 -- returns the assignment statement:
465 -- Into (Indices, Ind) := Expr;
467 -- Otherwise we call Build_Code recursively
469 -- Ada 2005 (AI-287): In case of default initialized component, Expr
470 -- is empty and we generate a call to the corresponding IP subprogram.
472 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id;
473 -- Nodes L and H must be side-effect free expressions.
474 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
475 -- This routine returns the for loop statement
477 -- for J in Index_Base'(L) .. Index_Base'(H) loop
478 -- Into (Indices, J) := Expr;
479 -- end loop;
481 -- Otherwise we call Build_Code recursively.
482 -- As an optimization if the loop covers 3 or less scalar elements we
483 -- generate a sequence of assignments.
485 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id;
486 -- Nodes L and H must be side-effect free expressions.
487 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
488 -- This routine returns the while loop statement
490 -- J : Index_Base := L;
491 -- while J < H loop
492 -- J := Index_Base'Succ (J);
493 -- Into (Indices, J) := Expr;
494 -- end loop;
496 -- Otherwise we call Build_Code recursively
498 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean;
499 function Local_Expr_Value (E : Node_Id) return Uint;
500 -- These two Local routines are used to replace the corresponding ones
501 -- in sem_eval because while processing the bounds of an aggregate with
502 -- discrete choices whose index type is an enumeration, we build static
503 -- expressions not recognized by Compile_Time_Known_Value as such since
504 -- they have not yet been analyzed and resolved. All the expressions in
505 -- question are things like Index_Base_Name'Val (Const) which we can
506 -- easily recognize as being constant.
508 ---------
509 -- Add --
510 ---------
512 function Add (Val : Int; To : Node_Id) return Node_Id is
513 Expr_Pos : Node_Id;
514 Expr : Node_Id;
515 To_Pos : Node_Id;
516 U_To : Uint;
517 U_Val : constant Uint := UI_From_Int (Val);
519 begin
520 -- Note: do not try to optimize the case of Val = 0, because
521 -- we need to build a new node with the proper Sloc value anyway.
523 -- First test if we can do constant folding
525 if Local_Compile_Time_Known_Value (To) then
526 U_To := Local_Expr_Value (To) + Val;
528 -- Determine if our constant is outside the range of the index.
529 -- If so return an Empty node. This empty node will be caught
530 -- by Empty_Range below.
532 if Compile_Time_Known_Value (Index_Base_L)
533 and then U_To < Expr_Value (Index_Base_L)
534 then
535 return Empty;
537 elsif Compile_Time_Known_Value (Index_Base_H)
538 and then U_To > Expr_Value (Index_Base_H)
539 then
540 return Empty;
541 end if;
543 Expr_Pos := Make_Integer_Literal (Loc, U_To);
544 Set_Is_Static_Expression (Expr_Pos);
546 if not Is_Enumeration_Type (Index_Base) then
547 Expr := Expr_Pos;
549 -- If we are dealing with enumeration return
550 -- Index_Base'Val (Expr_Pos)
552 else
553 Expr :=
554 Make_Attribute_Reference
555 (Loc,
556 Prefix => Index_Base_Name,
557 Attribute_Name => Name_Val,
558 Expressions => New_List (Expr_Pos));
559 end if;
561 return Expr;
562 end if;
564 -- If we are here no constant folding possible
566 if not Is_Enumeration_Type (Index_Base) then
567 Expr :=
568 Make_Op_Add (Loc,
569 Left_Opnd => Duplicate_Subexpr (To),
570 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
572 -- If we are dealing with enumeration return
573 -- Index_Base'Val (Index_Base'Pos (To) + Val)
575 else
576 To_Pos :=
577 Make_Attribute_Reference
578 (Loc,
579 Prefix => Index_Base_Name,
580 Attribute_Name => Name_Pos,
581 Expressions => New_List (Duplicate_Subexpr (To)));
583 Expr_Pos :=
584 Make_Op_Add (Loc,
585 Left_Opnd => To_Pos,
586 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
588 Expr :=
589 Make_Attribute_Reference
590 (Loc,
591 Prefix => Index_Base_Name,
592 Attribute_Name => Name_Val,
593 Expressions => New_List (Expr_Pos));
594 end if;
596 return Expr;
597 end Add;
599 -----------------
600 -- Empty_Range --
601 -----------------
603 function Empty_Range (L, H : Node_Id) return Boolean is
604 Is_Empty : Boolean := False;
605 Low : Node_Id;
606 High : Node_Id;
608 begin
609 -- First check if L or H were already detected as overflowing the
610 -- index base range type by function Add above. If this is so Add
611 -- returns the empty node.
613 if No (L) or else No (H) then
614 return True;
615 end if;
617 for J in 1 .. 3 loop
618 case J is
620 -- L > H range is empty
622 when 1 =>
623 Low := L;
624 High := H;
626 -- B_L > H range must be empty
628 when 2 =>
629 Low := Index_Base_L;
630 High := H;
632 -- L > B_H range must be empty
634 when 3 =>
635 Low := L;
636 High := Index_Base_H;
637 end case;
639 if Local_Compile_Time_Known_Value (Low)
640 and then Local_Compile_Time_Known_Value (High)
641 then
642 Is_Empty :=
643 UI_Gt (Local_Expr_Value (Low), Local_Expr_Value (High));
644 end if;
646 exit when Is_Empty;
647 end loop;
649 return Is_Empty;
650 end Empty_Range;
652 -----------
653 -- Equal --
654 -----------
656 function Equal (L, H : Node_Id) return Boolean is
657 begin
658 if L = H then
659 return True;
661 elsif Local_Compile_Time_Known_Value (L)
662 and then Local_Compile_Time_Known_Value (H)
663 then
664 return UI_Eq (Local_Expr_Value (L), Local_Expr_Value (H));
665 end if;
667 return False;
668 end Equal;
670 ----------------
671 -- Gen_Assign --
672 ----------------
674 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id is
675 L : constant List_Id := New_List;
676 F : Entity_Id;
677 A : Node_Id;
679 New_Indices : List_Id;
680 Indexed_Comp : Node_Id;
681 Expr_Q : Node_Id;
682 Comp_Type : Entity_Id := Empty;
684 function Add_Loop_Actions (Lis : List_Id) return List_Id;
685 -- Collect insert_actions generated in the construction of a
686 -- loop, and prepend them to the sequence of assignments to
687 -- complete the eventual body of the loop.
689 ----------------------
690 -- Add_Loop_Actions --
691 ----------------------
693 function Add_Loop_Actions (Lis : List_Id) return List_Id is
694 Res : List_Id;
696 begin
697 -- Ada 2005 (AI-287): Do nothing else in case of default
698 -- initialized component.
700 if not Present (Expr) then
701 return Lis;
703 elsif Nkind (Parent (Expr)) = N_Component_Association
704 and then Present (Loop_Actions (Parent (Expr)))
705 then
706 Append_List (Lis, Loop_Actions (Parent (Expr)));
707 Res := Loop_Actions (Parent (Expr));
708 Set_Loop_Actions (Parent (Expr), No_List);
709 return Res;
711 else
712 return Lis;
713 end if;
714 end Add_Loop_Actions;
716 -- Start of processing for Gen_Assign
718 begin
719 if No (Indices) then
720 New_Indices := New_List;
721 else
722 New_Indices := New_Copy_List_Tree (Indices);
723 end if;
725 Append_To (New_Indices, Ind);
727 if Present (Flist) then
728 F := New_Copy_Tree (Flist);
730 elsif Present (Etype (N)) and then Controlled_Type (Etype (N)) then
731 if Is_Entity_Name (Into)
732 and then Present (Scope (Entity (Into)))
733 then
734 F := Find_Final_List (Scope (Entity (Into)));
735 else
736 F := Find_Final_List (Current_Scope);
737 end if;
738 else
739 F := Empty;
740 end if;
742 if Present (Next_Index (Index)) then
743 return
744 Add_Loop_Actions (
745 Build_Array_Aggr_Code
746 (N => Expr,
747 Ctype => Ctype,
748 Index => Next_Index (Index),
749 Into => Into,
750 Scalar_Comp => Scalar_Comp,
751 Indices => New_Indices,
752 Flist => F));
753 end if;
755 -- If we get here then we are at a bottom-level (sub-)aggregate
757 Indexed_Comp :=
758 Checks_Off
759 (Make_Indexed_Component (Loc,
760 Prefix => New_Copy_Tree (Into),
761 Expressions => New_Indices));
763 Set_Assignment_OK (Indexed_Comp);
765 -- Ada 2005 (AI-287): In case of default initialized component, Expr
766 -- is not present (and therefore we also initialize Expr_Q to empty).
768 if not Present (Expr) then
769 Expr_Q := Empty;
770 elsif Nkind (Expr) = N_Qualified_Expression then
771 Expr_Q := Expression (Expr);
772 else
773 Expr_Q := Expr;
774 end if;
776 if Present (Etype (N))
777 and then Etype (N) /= Any_Composite
778 then
779 Comp_Type := Component_Type (Etype (N));
780 pragma Assert (Comp_Type = Ctype); -- AI-287
782 elsif Present (Next (First (New_Indices))) then
784 -- Ada 2005 (AI-287): Do nothing in case of default initialized
785 -- component because we have received the component type in
786 -- the formal parameter Ctype.
788 -- ??? Some assert pragmas have been added to check if this new
789 -- formal can be used to replace this code in all cases.
791 if Present (Expr) then
793 -- This is a multidimensional array. Recover the component
794 -- type from the outermost aggregate, because subaggregates
795 -- do not have an assigned type.
797 declare
798 P : Node_Id := Parent (Expr);
800 begin
801 while Present (P) loop
802 if Nkind (P) = N_Aggregate
803 and then Present (Etype (P))
804 then
805 Comp_Type := Component_Type (Etype (P));
806 exit;
808 else
809 P := Parent (P);
810 end if;
811 end loop;
813 pragma Assert (Comp_Type = Ctype); -- AI-287
814 end;
815 end if;
816 end if;
818 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
819 -- default initialized components (otherwise Expr_Q is not present).
821 if Present (Expr_Q)
822 and then (Nkind (Expr_Q) = N_Aggregate
823 or else Nkind (Expr_Q) = N_Extension_Aggregate)
824 then
825 -- At this stage the Expression may not have been
826 -- analyzed yet because the array aggregate code has not
827 -- been updated to use the Expansion_Delayed flag and
828 -- avoid analysis altogether to solve the same problem
829 -- (see Resolve_Aggr_Expr). So let us do the analysis of
830 -- non-array aggregates now in order to get the value of
831 -- Expansion_Delayed flag for the inner aggregate ???
833 if Present (Comp_Type) and then not Is_Array_Type (Comp_Type) then
834 Analyze_And_Resolve (Expr_Q, Comp_Type);
835 end if;
837 if Is_Delayed_Aggregate (Expr_Q) then
839 -- This is either a subaggregate of a multidimentional array,
840 -- or a component of an array type whose component type is
841 -- also an array. In the latter case, the expression may have
842 -- component associations that provide different bounds from
843 -- those of the component type, and sliding must occur. Instead
844 -- of decomposing the current aggregate assignment, force the
845 -- re-analysis of the assignment, so that a temporary will be
846 -- generated in the usual fashion, and sliding will take place.
848 if Nkind (Parent (N)) = N_Assignment_Statement
849 and then Is_Array_Type (Comp_Type)
850 and then Present (Component_Associations (Expr_Q))
851 and then Must_Slide (Comp_Type, Etype (Expr_Q))
852 then
853 Set_Expansion_Delayed (Expr_Q, False);
854 Set_Analyzed (Expr_Q, False);
856 else
857 return
858 Add_Loop_Actions (
859 Late_Expansion (
860 Expr_Q, Etype (Expr_Q), Indexed_Comp, F));
861 end if;
862 end if;
863 end if;
865 -- Ada 2005 (AI-287): In case of default initialized component, call
866 -- the initialization subprogram associated with the component type.
868 if not Present (Expr) then
870 if Present (Base_Init_Proc (Etype (Ctype)))
871 or else Has_Task (Base_Type (Ctype))
872 then
873 Append_List_To (L,
874 Build_Initialization_Call (Loc,
875 Id_Ref => Indexed_Comp,
876 Typ => Ctype,
877 With_Default_Init => True));
878 end if;
880 else
881 -- Now generate the assignment with no associated controlled
882 -- actions since the target of the assignment may not have
883 -- been initialized, it is not possible to Finalize it as
884 -- expected by normal controlled assignment. The rest of the
885 -- controlled actions are done manually with the proper
886 -- finalization list coming from the context.
888 A :=
889 Make_OK_Assignment_Statement (Loc,
890 Name => Indexed_Comp,
891 Expression => New_Copy_Tree (Expr));
893 if Present (Comp_Type) and then Controlled_Type (Comp_Type) then
894 Set_No_Ctrl_Actions (A);
895 end if;
897 Append_To (L, A);
899 -- Adjust the tag if tagged (because of possible view
900 -- conversions), unless compiling for the Java VM
901 -- where tags are implicit.
903 if Present (Comp_Type)
904 and then Is_Tagged_Type (Comp_Type)
905 and then not Java_VM
906 then
907 A :=
908 Make_OK_Assignment_Statement (Loc,
909 Name =>
910 Make_Selected_Component (Loc,
911 Prefix => New_Copy_Tree (Indexed_Comp),
912 Selector_Name =>
913 New_Reference_To (Tag_Component (Comp_Type), Loc)),
915 Expression =>
916 Unchecked_Convert_To (RTE (RE_Tag),
917 New_Reference_To (
918 Access_Disp_Table (Comp_Type), Loc)));
920 Append_To (L, A);
921 end if;
923 -- Adjust and Attach the component to the proper final list
924 -- which can be the controller of the outer record object or
925 -- the final list associated with the scope
927 if Present (Comp_Type) and then Controlled_Type (Comp_Type) then
928 Append_List_To (L,
929 Make_Adjust_Call (
930 Ref => New_Copy_Tree (Indexed_Comp),
931 Typ => Comp_Type,
932 Flist_Ref => F,
933 With_Attach => Make_Integer_Literal (Loc, 1)));
934 end if;
935 end if;
937 return Add_Loop_Actions (L);
938 end Gen_Assign;
940 --------------
941 -- Gen_Loop --
942 --------------
944 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id is
945 L_J : Node_Id;
947 L_Range : Node_Id;
948 -- Index_Base'(L) .. Index_Base'(H)
950 L_Iteration_Scheme : Node_Id;
951 -- L_J in Index_Base'(L) .. Index_Base'(H)
953 L_Body : List_Id;
954 -- The statements to execute in the loop
956 S : constant List_Id := New_List;
957 -- List of statements
959 Tcopy : Node_Id;
960 -- Copy of expression tree, used for checking purposes
962 begin
963 -- If loop bounds define an empty range return the null statement
965 if Empty_Range (L, H) then
966 Append_To (S, Make_Null_Statement (Loc));
968 -- Ada 2005 (AI-287): Nothing else need to be done in case of
969 -- default initialized component.
971 if not Present (Expr) then
972 null;
974 else
975 -- The expression must be type-checked even though no component
976 -- of the aggregate will have this value. This is done only for
977 -- actual components of the array, not for subaggregates. Do
978 -- the check on a copy, because the expression may be shared
979 -- among several choices, some of which might be non-null.
981 if Present (Etype (N))
982 and then Is_Array_Type (Etype (N))
983 and then No (Next_Index (Index))
984 then
985 Expander_Mode_Save_And_Set (False);
986 Tcopy := New_Copy_Tree (Expr);
987 Set_Parent (Tcopy, N);
988 Analyze_And_Resolve (Tcopy, Component_Type (Etype (N)));
989 Expander_Mode_Restore;
990 end if;
991 end if;
993 return S;
995 -- If loop bounds are the same then generate an assignment
997 elsif Equal (L, H) then
998 return Gen_Assign (New_Copy_Tree (L), Expr);
1000 -- If H - L <= 2 then generate a sequence of assignments
1001 -- when we are processing the bottom most aggregate and it contains
1002 -- scalar components.
1004 elsif No (Next_Index (Index))
1005 and then Scalar_Comp
1006 and then Local_Compile_Time_Known_Value (L)
1007 and then Local_Compile_Time_Known_Value (H)
1008 and then Local_Expr_Value (H) - Local_Expr_Value (L) <= 2
1009 then
1011 Append_List_To (S, Gen_Assign (New_Copy_Tree (L), Expr));
1012 Append_List_To (S, Gen_Assign (Add (1, To => L), Expr));
1014 if Local_Expr_Value (H) - Local_Expr_Value (L) = 2 then
1015 Append_List_To (S, Gen_Assign (Add (2, To => L), Expr));
1016 end if;
1018 return S;
1019 end if;
1021 -- Otherwise construct the loop, starting with the loop index L_J
1023 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
1025 -- Construct "L .. H"
1027 L_Range :=
1028 Make_Range
1029 (Loc,
1030 Low_Bound => Make_Qualified_Expression
1031 (Loc,
1032 Subtype_Mark => Index_Base_Name,
1033 Expression => L),
1034 High_Bound => Make_Qualified_Expression
1035 (Loc,
1036 Subtype_Mark => Index_Base_Name,
1037 Expression => H));
1039 -- Construct "for L_J in Index_Base range L .. H"
1041 L_Iteration_Scheme :=
1042 Make_Iteration_Scheme
1043 (Loc,
1044 Loop_Parameter_Specification =>
1045 Make_Loop_Parameter_Specification
1046 (Loc,
1047 Defining_Identifier => L_J,
1048 Discrete_Subtype_Definition => L_Range));
1050 -- Construct the statements to execute in the loop body
1052 L_Body := Gen_Assign (New_Reference_To (L_J, Loc), Expr);
1054 -- Construct the final loop
1056 Append_To (S, Make_Implicit_Loop_Statement
1057 (Node => N,
1058 Identifier => Empty,
1059 Iteration_Scheme => L_Iteration_Scheme,
1060 Statements => L_Body));
1062 return S;
1063 end Gen_Loop;
1065 ---------------
1066 -- Gen_While --
1067 ---------------
1069 -- The code built is
1071 -- W_J : Index_Base := L;
1072 -- while W_J < H loop
1073 -- W_J := Index_Base'Succ (W);
1074 -- L_Body;
1075 -- end loop;
1077 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id is
1078 W_J : Node_Id;
1080 W_Decl : Node_Id;
1081 -- W_J : Base_Type := L;
1083 W_Iteration_Scheme : Node_Id;
1084 -- while W_J < H
1086 W_Index_Succ : Node_Id;
1087 -- Index_Base'Succ (J)
1089 W_Increment : Node_Id;
1090 -- W_J := Index_Base'Succ (W)
1092 W_Body : constant List_Id := New_List;
1093 -- The statements to execute in the loop
1095 S : constant List_Id := New_List;
1096 -- list of statement
1098 begin
1099 -- If loop bounds define an empty range or are equal return null
1101 if Empty_Range (L, H) or else Equal (L, H) then
1102 Append_To (S, Make_Null_Statement (Loc));
1103 return S;
1104 end if;
1106 -- Build the decl of W_J
1108 W_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
1109 W_Decl :=
1110 Make_Object_Declaration
1111 (Loc,
1112 Defining_Identifier => W_J,
1113 Object_Definition => Index_Base_Name,
1114 Expression => L);
1116 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1117 -- that in this particular case L is a fresh Expr generated by
1118 -- Add which we are the only ones to use.
1120 Append_To (S, W_Decl);
1122 -- Construct " while W_J < H"
1124 W_Iteration_Scheme :=
1125 Make_Iteration_Scheme
1126 (Loc,
1127 Condition => Make_Op_Lt
1128 (Loc,
1129 Left_Opnd => New_Reference_To (W_J, Loc),
1130 Right_Opnd => New_Copy_Tree (H)));
1132 -- Construct the statements to execute in the loop body
1134 W_Index_Succ :=
1135 Make_Attribute_Reference
1136 (Loc,
1137 Prefix => Index_Base_Name,
1138 Attribute_Name => Name_Succ,
1139 Expressions => New_List (New_Reference_To (W_J, Loc)));
1141 W_Increment :=
1142 Make_OK_Assignment_Statement
1143 (Loc,
1144 Name => New_Reference_To (W_J, Loc),
1145 Expression => W_Index_Succ);
1147 Append_To (W_Body, W_Increment);
1148 Append_List_To (W_Body,
1149 Gen_Assign (New_Reference_To (W_J, Loc), Expr));
1151 -- Construct the final loop
1153 Append_To (S, Make_Implicit_Loop_Statement
1154 (Node => N,
1155 Identifier => Empty,
1156 Iteration_Scheme => W_Iteration_Scheme,
1157 Statements => W_Body));
1159 return S;
1160 end Gen_While;
1162 ---------------------
1163 -- Index_Base_Name --
1164 ---------------------
1166 function Index_Base_Name return Node_Id is
1167 begin
1168 return New_Reference_To (Index_Base, Sloc (N));
1169 end Index_Base_Name;
1171 ------------------------------------
1172 -- Local_Compile_Time_Known_Value --
1173 ------------------------------------
1175 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean is
1176 begin
1177 return Compile_Time_Known_Value (E)
1178 or else
1179 (Nkind (E) = N_Attribute_Reference
1180 and then Attribute_Name (E) = Name_Val
1181 and then Compile_Time_Known_Value (First (Expressions (E))));
1182 end Local_Compile_Time_Known_Value;
1184 ----------------------
1185 -- Local_Expr_Value --
1186 ----------------------
1188 function Local_Expr_Value (E : Node_Id) return Uint is
1189 begin
1190 if Compile_Time_Known_Value (E) then
1191 return Expr_Value (E);
1192 else
1193 return Expr_Value (First (Expressions (E)));
1194 end if;
1195 end Local_Expr_Value;
1197 -- Build_Array_Aggr_Code Variables
1199 Assoc : Node_Id;
1200 Choice : Node_Id;
1201 Expr : Node_Id;
1202 Typ : Entity_Id;
1204 Others_Expr : Node_Id := Empty;
1205 Others_Mbox_Present : Boolean := False;
1207 Aggr_L : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
1208 Aggr_H : constant Node_Id := High_Bound (Aggregate_Bounds (N));
1209 -- The aggregate bounds of this specific sub-aggregate. Note that if
1210 -- the code generated by Build_Array_Aggr_Code is executed then these
1211 -- bounds are OK. Otherwise a Constraint_Error would have been raised.
1213 Aggr_Low : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_L);
1214 Aggr_High : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_H);
1215 -- After Duplicate_Subexpr these are side-effect free
1217 Low : Node_Id;
1218 High : Node_Id;
1220 Nb_Choices : Nat := 0;
1221 Table : Case_Table_Type (1 .. Number_Of_Choices (N));
1222 -- Used to sort all the different choice values
1224 Nb_Elements : Int;
1225 -- Number of elements in the positional aggregate
1227 New_Code : constant List_Id := New_List;
1229 -- Start of processing for Build_Array_Aggr_Code
1231 begin
1232 -- First before we start, a special case. if we have a bit packed
1233 -- array represented as a modular type, then clear the value to
1234 -- zero first, to ensure that unused bits are properly cleared.
1236 Typ := Etype (N);
1238 if Present (Typ)
1239 and then Is_Bit_Packed_Array (Typ)
1240 and then Is_Modular_Integer_Type (Packed_Array_Type (Typ))
1241 then
1242 Append_To (New_Code,
1243 Make_Assignment_Statement (Loc,
1244 Name => New_Copy_Tree (Into),
1245 Expression =>
1246 Unchecked_Convert_To (Typ,
1247 Make_Integer_Literal (Loc, Uint_0))));
1248 end if;
1250 -- We can skip this
1251 -- STEP 1: Process component associations
1252 -- For those associations that may generate a loop, initialize
1253 -- Loop_Actions to collect inserted actions that may be crated.
1255 if No (Expressions (N)) then
1257 -- STEP 1 (a): Sort the discrete choices
1259 Assoc := First (Component_Associations (N));
1260 while Present (Assoc) loop
1261 Choice := First (Choices (Assoc));
1262 while Present (Choice) loop
1263 if Nkind (Choice) = N_Others_Choice then
1264 Set_Loop_Actions (Assoc, New_List);
1266 if Box_Present (Assoc) then
1267 Others_Mbox_Present := True;
1268 else
1269 Others_Expr := Expression (Assoc);
1270 end if;
1271 exit;
1272 end if;
1274 Get_Index_Bounds (Choice, Low, High);
1276 if Low /= High then
1277 Set_Loop_Actions (Assoc, New_List);
1278 end if;
1280 Nb_Choices := Nb_Choices + 1;
1281 if Box_Present (Assoc) then
1282 Table (Nb_Choices) := (Choice_Lo => Low,
1283 Choice_Hi => High,
1284 Choice_Node => Empty);
1285 else
1286 Table (Nb_Choices) := (Choice_Lo => Low,
1287 Choice_Hi => High,
1288 Choice_Node => Expression (Assoc));
1289 end if;
1290 Next (Choice);
1291 end loop;
1293 Next (Assoc);
1294 end loop;
1296 -- If there is more than one set of choices these must be static
1297 -- and we can therefore sort them. Remember that Nb_Choices does not
1298 -- account for an others choice.
1300 if Nb_Choices > 1 then
1301 Sort_Case_Table (Table);
1302 end if;
1304 -- STEP 1 (b): take care of the whole set of discrete choices
1306 for J in 1 .. Nb_Choices loop
1307 Low := Table (J).Choice_Lo;
1308 High := Table (J).Choice_Hi;
1309 Expr := Table (J).Choice_Node;
1310 Append_List (Gen_Loop (Low, High, Expr), To => New_Code);
1311 end loop;
1313 -- STEP 1 (c): generate the remaining loops to cover others choice
1314 -- We don't need to generate loops over empty gaps, but if there is
1315 -- a single empty range we must analyze the expression for semantics
1317 if Present (Others_Expr) or else Others_Mbox_Present then
1318 declare
1319 First : Boolean := True;
1321 begin
1322 for J in 0 .. Nb_Choices loop
1323 if J = 0 then
1324 Low := Aggr_Low;
1325 else
1326 Low := Add (1, To => Table (J).Choice_Hi);
1327 end if;
1329 if J = Nb_Choices then
1330 High := Aggr_High;
1331 else
1332 High := Add (-1, To => Table (J + 1).Choice_Lo);
1333 end if;
1335 -- If this is an expansion within an init proc, make
1336 -- sure that discriminant references are replaced by
1337 -- the corresponding discriminal.
1339 if Inside_Init_Proc then
1340 if Is_Entity_Name (Low)
1341 and then Ekind (Entity (Low)) = E_Discriminant
1342 then
1343 Set_Entity (Low, Discriminal (Entity (Low)));
1344 end if;
1346 if Is_Entity_Name (High)
1347 and then Ekind (Entity (High)) = E_Discriminant
1348 then
1349 Set_Entity (High, Discriminal (Entity (High)));
1350 end if;
1351 end if;
1353 if First
1354 or else not Empty_Range (Low, High)
1355 then
1356 First := False;
1357 Append_List
1358 (Gen_Loop (Low, High, Others_Expr), To => New_Code);
1359 end if;
1360 end loop;
1361 end;
1362 end if;
1364 -- STEP 2: Process positional components
1366 else
1367 -- STEP 2 (a): Generate the assignments for each positional element
1368 -- Note that here we have to use Aggr_L rather than Aggr_Low because
1369 -- Aggr_L is analyzed and Add wants an analyzed expression.
1371 Expr := First (Expressions (N));
1372 Nb_Elements := -1;
1374 while Present (Expr) loop
1375 Nb_Elements := Nb_Elements + 1;
1376 Append_List (Gen_Assign (Add (Nb_Elements, To => Aggr_L), Expr),
1377 To => New_Code);
1378 Next (Expr);
1379 end loop;
1381 -- STEP 2 (b): Generate final loop if an others choice is present
1382 -- Here Nb_Elements gives the offset of the last positional element.
1384 if Present (Component_Associations (N)) then
1385 Assoc := Last (Component_Associations (N));
1387 -- Ada 2005 (AI-287)
1389 if Box_Present (Assoc) then
1390 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1391 Aggr_High,
1392 Empty),
1393 To => New_Code);
1394 else
1395 Expr := Expression (Assoc);
1397 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1398 Aggr_High,
1399 Expr), -- AI-287
1400 To => New_Code);
1401 end if;
1402 end if;
1403 end if;
1405 return New_Code;
1406 end Build_Array_Aggr_Code;
1408 ----------------------------
1409 -- Build_Record_Aggr_Code --
1410 ----------------------------
1412 function Build_Record_Aggr_Code
1413 (N : Node_Id;
1414 Typ : Entity_Id;
1415 Target : Node_Id;
1416 Flist : Node_Id := Empty;
1417 Obj : Entity_Id := Empty;
1418 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id
1420 Loc : constant Source_Ptr := Sloc (N);
1421 L : constant List_Id := New_List;
1422 Start_L : constant List_Id := New_List;
1423 N_Typ : constant Entity_Id := Etype (N);
1425 Comp : Node_Id;
1426 Instr : Node_Id;
1427 Ref : Node_Id;
1428 F : Node_Id;
1429 Comp_Type : Entity_Id;
1430 Selector : Entity_Id;
1431 Comp_Expr : Node_Id;
1432 Expr_Q : Node_Id;
1434 Internal_Final_List : Node_Id;
1436 -- If this is an internal aggregate, the External_Final_List is an
1437 -- expression for the controller record of the enclosing type.
1438 -- If the current aggregate has several controlled components, this
1439 -- expression will appear in several calls to attach to the finali-
1440 -- zation list, and it must not be shared.
1442 External_Final_List : Node_Id;
1443 Ancestor_Is_Expression : Boolean := False;
1444 Ancestor_Is_Subtype_Mark : Boolean := False;
1446 Init_Typ : Entity_Id := Empty;
1447 Attach : Node_Id;
1449 function Get_Constraint_Association (T : Entity_Id) return Node_Id;
1450 -- Returns the first discriminant association in the constraint
1451 -- associated with T, if any, otherwise returns Empty.
1453 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id;
1454 -- Returns the value that the given discriminant of an ancestor
1455 -- type should receive (in the absence of a conflict with the
1456 -- value provided by an ancestor part of an extension aggregate).
1458 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id);
1459 -- Check that each of the discriminant values defined by the
1460 -- ancestor part of an extension aggregate match the corresponding
1461 -- values provided by either an association of the aggregate or
1462 -- by the constraint imposed by a parent type (RM95-4.3.2(8)).
1464 function Init_Controller
1465 (Target : Node_Id;
1466 Typ : Entity_Id;
1467 F : Node_Id;
1468 Attach : Node_Id;
1469 Init_Pr : Boolean) return List_Id;
1470 -- returns the list of statements necessary to initialize the internal
1471 -- controller of the (possible) ancestor typ into target and attach
1472 -- it to finalization list F. Init_Pr conditions the call to the
1473 -- init proc since it may already be done due to ancestor initialization
1475 ---------------------------------
1476 -- Ancestor_Discriminant_Value --
1477 ---------------------------------
1479 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id is
1480 Assoc : Node_Id;
1481 Assoc_Elmt : Elmt_Id;
1482 Aggr_Comp : Entity_Id;
1483 Corresp_Disc : Entity_Id;
1484 Current_Typ : Entity_Id := Base_Type (Typ);
1485 Parent_Typ : Entity_Id;
1486 Parent_Disc : Entity_Id;
1487 Save_Assoc : Node_Id := Empty;
1489 begin
1490 -- First check any discriminant associations to see if
1491 -- any of them provide a value for the discriminant.
1493 if Present (Discriminant_Specifications (Parent (Current_Typ))) then
1494 Assoc := First (Component_Associations (N));
1495 while Present (Assoc) loop
1496 Aggr_Comp := Entity (First (Choices (Assoc)));
1498 if Ekind (Aggr_Comp) = E_Discriminant then
1499 Save_Assoc := Expression (Assoc);
1501 Corresp_Disc := Corresponding_Discriminant (Aggr_Comp);
1502 while Present (Corresp_Disc) loop
1503 -- If found a corresponding discriminant then return
1504 -- the value given in the aggregate. (Note: this is
1505 -- not correct in the presence of side effects. ???)
1507 if Disc = Corresp_Disc then
1508 return Duplicate_Subexpr (Expression (Assoc));
1509 end if;
1511 Corresp_Disc :=
1512 Corresponding_Discriminant (Corresp_Disc);
1513 end loop;
1514 end if;
1516 Next (Assoc);
1517 end loop;
1518 end if;
1520 -- No match found in aggregate, so chain up parent types to find
1521 -- a constraint that defines the value of the discriminant.
1523 Parent_Typ := Etype (Current_Typ);
1524 while Current_Typ /= Parent_Typ loop
1525 if Has_Discriminants (Parent_Typ) then
1526 Parent_Disc := First_Discriminant (Parent_Typ);
1528 -- We either get the association from the subtype indication
1529 -- of the type definition itself, or from the discriminant
1530 -- constraint associated with the type entity (which is
1531 -- preferable, but it's not always present ???)
1533 if Is_Empty_Elmt_List (
1534 Discriminant_Constraint (Current_Typ))
1535 then
1536 Assoc := Get_Constraint_Association (Current_Typ);
1537 Assoc_Elmt := No_Elmt;
1538 else
1539 Assoc_Elmt :=
1540 First_Elmt (Discriminant_Constraint (Current_Typ));
1541 Assoc := Node (Assoc_Elmt);
1542 end if;
1544 -- Traverse the discriminants of the parent type looking
1545 -- for one that corresponds.
1547 while Present (Parent_Disc) and then Present (Assoc) loop
1548 Corresp_Disc := Parent_Disc;
1549 while Present (Corresp_Disc)
1550 and then Disc /= Corresp_Disc
1551 loop
1552 Corresp_Disc :=
1553 Corresponding_Discriminant (Corresp_Disc);
1554 end loop;
1556 if Disc = Corresp_Disc then
1557 if Nkind (Assoc) = N_Discriminant_Association then
1558 Assoc := Expression (Assoc);
1559 end if;
1561 -- If the located association directly denotes
1562 -- a discriminant, then use the value of a saved
1563 -- association of the aggregate. This is a kludge
1564 -- to handle certain cases involving multiple
1565 -- discriminants mapped to a single discriminant
1566 -- of a descendant. It's not clear how to locate the
1567 -- appropriate discriminant value for such cases. ???
1569 if Is_Entity_Name (Assoc)
1570 and then Ekind (Entity (Assoc)) = E_Discriminant
1571 then
1572 Assoc := Save_Assoc;
1573 end if;
1575 return Duplicate_Subexpr (Assoc);
1576 end if;
1578 Next_Discriminant (Parent_Disc);
1580 if No (Assoc_Elmt) then
1581 Next (Assoc);
1582 else
1583 Next_Elmt (Assoc_Elmt);
1584 if Present (Assoc_Elmt) then
1585 Assoc := Node (Assoc_Elmt);
1586 else
1587 Assoc := Empty;
1588 end if;
1589 end if;
1590 end loop;
1591 end if;
1593 Current_Typ := Parent_Typ;
1594 Parent_Typ := Etype (Current_Typ);
1595 end loop;
1597 -- In some cases there's no ancestor value to locate (such as
1598 -- when an ancestor part given by an expression defines the
1599 -- discriminant value).
1601 return Empty;
1602 end Ancestor_Discriminant_Value;
1604 ----------------------------------
1605 -- Check_Ancestor_Discriminants --
1606 ----------------------------------
1608 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id) is
1609 Discr : Entity_Id := First_Discriminant (Base_Type (Anc_Typ));
1610 Disc_Value : Node_Id;
1611 Cond : Node_Id;
1613 begin
1614 while Present (Discr) loop
1615 Disc_Value := Ancestor_Discriminant_Value (Discr);
1617 if Present (Disc_Value) then
1618 Cond := Make_Op_Ne (Loc,
1619 Left_Opnd =>
1620 Make_Selected_Component (Loc,
1621 Prefix => New_Copy_Tree (Target),
1622 Selector_Name => New_Occurrence_Of (Discr, Loc)),
1623 Right_Opnd => Disc_Value);
1625 Append_To (L,
1626 Make_Raise_Constraint_Error (Loc,
1627 Condition => Cond,
1628 Reason => CE_Discriminant_Check_Failed));
1629 end if;
1631 Next_Discriminant (Discr);
1632 end loop;
1633 end Check_Ancestor_Discriminants;
1635 --------------------------------
1636 -- Get_Constraint_Association --
1637 --------------------------------
1639 function Get_Constraint_Association (T : Entity_Id) return Node_Id is
1640 Typ_Def : constant Node_Id := Type_Definition (Parent (T));
1641 Indic : constant Node_Id := Subtype_Indication (Typ_Def);
1643 begin
1644 -- ??? Also need to cover case of a type mark denoting a subtype
1645 -- with constraint.
1647 if Nkind (Indic) = N_Subtype_Indication
1648 and then Present (Constraint (Indic))
1649 then
1650 return First (Constraints (Constraint (Indic)));
1651 end if;
1653 return Empty;
1654 end Get_Constraint_Association;
1656 ---------------------
1657 -- Init_controller --
1658 ---------------------
1660 function Init_Controller
1661 (Target : Node_Id;
1662 Typ : Entity_Id;
1663 F : Node_Id;
1664 Attach : Node_Id;
1665 Init_Pr : Boolean) return List_Id
1667 L : constant List_Id := New_List;
1668 Ref : Node_Id;
1670 begin
1671 -- Generate:
1672 -- init-proc (target._controller);
1673 -- initialize (target._controller);
1674 -- Attach_to_Final_List (target._controller, F);
1676 Ref :=
1677 Make_Selected_Component (Loc,
1678 Prefix => Convert_To (Typ, New_Copy_Tree (Target)),
1679 Selector_Name => Make_Identifier (Loc, Name_uController));
1680 Set_Assignment_OK (Ref);
1682 -- Ada 2005 (AI-287): Give support to default initialization of
1683 -- limited types and components.
1685 if (Nkind (Target) = N_Identifier
1686 and then Present (Etype (Target))
1687 and then Is_Limited_Type (Etype (Target)))
1688 or else
1689 (Nkind (Target) = N_Selected_Component
1690 and then Present (Etype (Selector_Name (Target)))
1691 and then Is_Limited_Type (Etype (Selector_Name (Target))))
1692 or else
1693 (Nkind (Target) = N_Unchecked_Type_Conversion
1694 and then Present (Etype (Target))
1695 and then Is_Limited_Type (Etype (Target)))
1696 or else
1697 (Nkind (Target) = N_Unchecked_Expression
1698 and then Nkind (Expression (Target)) = N_Indexed_Component
1699 and then Present (Etype (Prefix (Expression (Target))))
1700 and then Is_Limited_Type (Etype (Prefix (Expression (Target)))))
1701 then
1702 if Init_Pr then
1703 Append_List_To (L,
1704 Build_Initialization_Call (Loc,
1705 Id_Ref => Ref,
1706 Typ => RTE (RE_Limited_Record_Controller),
1707 In_Init_Proc => Within_Init_Proc));
1708 end if;
1710 Append_To (L,
1711 Make_Procedure_Call_Statement (Loc,
1712 Name =>
1713 New_Reference_To
1714 (Find_Prim_Op (RTE (RE_Limited_Record_Controller),
1715 Name_Initialize), Loc),
1716 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
1718 else
1719 if Init_Pr then
1720 Append_List_To (L,
1721 Build_Initialization_Call (Loc,
1722 Id_Ref => Ref,
1723 Typ => RTE (RE_Record_Controller),
1724 In_Init_Proc => Within_Init_Proc));
1725 end if;
1727 Append_To (L,
1728 Make_Procedure_Call_Statement (Loc,
1729 Name =>
1730 New_Reference_To (Find_Prim_Op (RTE (RE_Record_Controller),
1731 Name_Initialize), Loc),
1732 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
1734 end if;
1736 Append_To (L,
1737 Make_Attach_Call (
1738 Obj_Ref => New_Copy_Tree (Ref),
1739 Flist_Ref => F,
1740 With_Attach => Attach));
1741 return L;
1742 end Init_Controller;
1744 -- Start of processing for Build_Record_Aggr_Code
1746 begin
1747 -- Deal with the ancestor part of extension aggregates
1748 -- or with the discriminants of the root type
1750 if Nkind (N) = N_Extension_Aggregate then
1751 declare
1752 A : constant Node_Id := Ancestor_Part (N);
1754 begin
1755 -- If the ancestor part is a subtype mark "T", we generate
1757 -- init-proc (T(tmp)); if T is constrained and
1758 -- init-proc (S(tmp)); where S applies an appropriate
1759 -- constraint if T is unconstrained
1761 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
1762 Ancestor_Is_Subtype_Mark := True;
1764 if Is_Constrained (Entity (A)) then
1765 Init_Typ := Entity (A);
1767 -- For an ancestor part given by an unconstrained type
1768 -- mark, create a subtype constrained by appropriate
1769 -- corresponding discriminant values coming from either
1770 -- associations of the aggregate or a constraint on
1771 -- a parent type. The subtype will be used to generate
1772 -- the correct default value for the ancestor part.
1774 elsif Has_Discriminants (Entity (A)) then
1775 declare
1776 Anc_Typ : constant Entity_Id := Entity (A);
1777 Anc_Constr : constant List_Id := New_List;
1778 Discrim : Entity_Id;
1779 Disc_Value : Node_Id;
1780 New_Indic : Node_Id;
1781 Subt_Decl : Node_Id;
1783 begin
1784 Discrim := First_Discriminant (Anc_Typ);
1785 while Present (Discrim) loop
1786 Disc_Value := Ancestor_Discriminant_Value (Discrim);
1787 Append_To (Anc_Constr, Disc_Value);
1788 Next_Discriminant (Discrim);
1789 end loop;
1791 New_Indic :=
1792 Make_Subtype_Indication (Loc,
1793 Subtype_Mark => New_Occurrence_Of (Anc_Typ, Loc),
1794 Constraint =>
1795 Make_Index_Or_Discriminant_Constraint (Loc,
1796 Constraints => Anc_Constr));
1798 Init_Typ := Create_Itype (Ekind (Anc_Typ), N);
1800 Subt_Decl :=
1801 Make_Subtype_Declaration (Loc,
1802 Defining_Identifier => Init_Typ,
1803 Subtype_Indication => New_Indic);
1805 -- Itypes must be analyzed with checks off
1806 -- Declaration must have a parent for proper
1807 -- handling of subsidiary actions.
1809 Set_Parent (Subt_Decl, N);
1810 Analyze (Subt_Decl, Suppress => All_Checks);
1811 end;
1812 end if;
1814 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
1815 Set_Assignment_OK (Ref);
1817 if Has_Default_Init_Comps (N)
1818 or else Has_Task (Base_Type (Init_Typ))
1819 then
1820 Append_List_To (Start_L,
1821 Build_Initialization_Call (Loc,
1822 Id_Ref => Ref,
1823 Typ => Init_Typ,
1824 In_Init_Proc => Within_Init_Proc,
1825 With_Default_Init => True));
1826 else
1827 Append_List_To (Start_L,
1828 Build_Initialization_Call (Loc,
1829 Id_Ref => Ref,
1830 Typ => Init_Typ,
1831 In_Init_Proc => Within_Init_Proc));
1832 end if;
1834 if Is_Constrained (Entity (A))
1835 and then Has_Discriminants (Entity (A))
1836 then
1837 Check_Ancestor_Discriminants (Entity (A));
1838 end if;
1840 -- Ada 2005 (AI-287): If the ancestor part is a limited type,
1841 -- a recursive call expands the ancestor.
1843 elsif Is_Limited_Type (Etype (A)) then
1844 Ancestor_Is_Expression := True;
1846 Append_List_To (Start_L,
1847 Build_Record_Aggr_Code (
1848 N => Expression (A),
1849 Typ => Etype (Expression (A)),
1850 Target => Target,
1851 Flist => Flist,
1852 Obj => Obj,
1853 Is_Limited_Ancestor_Expansion => True));
1855 -- If the ancestor part is an expression "E", we generate
1856 -- T(tmp) := E;
1858 else
1859 Ancestor_Is_Expression := True;
1860 Init_Typ := Etype (A);
1862 -- Assign the tag before doing the assignment to make sure
1863 -- that the dispatching call in the subsequent deep_adjust
1864 -- works properly (unless Java_VM, where tags are implicit).
1866 if not Java_VM then
1867 Instr :=
1868 Make_OK_Assignment_Statement (Loc,
1869 Name =>
1870 Make_Selected_Component (Loc,
1871 Prefix => New_Copy_Tree (Target),
1872 Selector_Name => New_Reference_To (
1873 Tag_Component (Base_Type (Typ)), Loc)),
1875 Expression =>
1876 Unchecked_Convert_To (RTE (RE_Tag),
1877 New_Reference_To (
1878 Access_Disp_Table (Base_Type (Typ)), Loc)));
1880 Set_Assignment_OK (Name (Instr));
1881 Append_To (L, Instr);
1882 end if;
1884 -- If the ancestor part is an aggregate, force its full
1885 -- expansion, which was delayed.
1887 if Nkind (A) = N_Qualified_Expression
1888 and then (Nkind (Expression (A)) = N_Aggregate
1889 or else
1890 Nkind (Expression (A)) = N_Extension_Aggregate)
1891 then
1892 Set_Analyzed (A, False);
1893 Set_Analyzed (Expression (A), False);
1894 end if;
1896 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
1897 Set_Assignment_OK (Ref);
1898 Append_To (L,
1899 Make_Unsuppress_Block (Loc,
1900 Name_Discriminant_Check,
1901 New_List (
1902 Make_OK_Assignment_Statement (Loc,
1903 Name => Ref,
1904 Expression => A))));
1906 if Has_Discriminants (Init_Typ) then
1907 Check_Ancestor_Discriminants (Init_Typ);
1908 end if;
1909 end if;
1910 end;
1912 -- Normal case (not an extension aggregate)
1914 else
1915 -- Generate the discriminant expressions, component by component.
1916 -- If the base type is an unchecked union, the discriminants are
1917 -- unknown to the back-end and absent from a value of the type, so
1918 -- assignments for them are not emitted.
1920 if Has_Discriminants (Typ)
1921 and then not Is_Unchecked_Union (Base_Type (Typ))
1922 then
1923 -- ??? The discriminants of the object not inherited in the type
1924 -- of the object should be initialized here
1926 null;
1928 -- Generate discriminant init values
1930 declare
1931 Discriminant : Entity_Id;
1932 Discriminant_Value : Node_Id;
1934 begin
1935 Discriminant := First_Stored_Discriminant (Typ);
1937 while Present (Discriminant) loop
1939 Comp_Expr :=
1940 Make_Selected_Component (Loc,
1941 Prefix => New_Copy_Tree (Target),
1942 Selector_Name => New_Occurrence_Of (Discriminant, Loc));
1944 Discriminant_Value :=
1945 Get_Discriminant_Value (
1946 Discriminant,
1947 N_Typ,
1948 Discriminant_Constraint (N_Typ));
1950 Instr :=
1951 Make_OK_Assignment_Statement (Loc,
1952 Name => Comp_Expr,
1953 Expression => New_Copy_Tree (Discriminant_Value));
1955 Set_No_Ctrl_Actions (Instr);
1956 Append_To (L, Instr);
1958 Next_Stored_Discriminant (Discriminant);
1959 end loop;
1960 end;
1961 end if;
1962 end if;
1964 -- Generate the assignments, component by component
1966 -- tmp.comp1 := Expr1_From_Aggr;
1967 -- tmp.comp2 := Expr2_From_Aggr;
1968 -- ....
1970 Comp := First (Component_Associations (N));
1971 while Present (Comp) loop
1972 Selector := Entity (First (Choices (Comp)));
1974 -- Ada 2005 (AI-287): Default initialization of a limited component
1976 if Box_Present (Comp)
1977 and then Is_Limited_Type (Etype (Selector))
1978 then
1979 -- Ada 2005 (AI-287): If the component type has tasks then
1980 -- generate the activation chain and master entities (except
1981 -- in case of an allocator because in that case these entities
1982 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
1984 declare
1985 Ctype : constant Entity_Id := Etype (Selector);
1986 Inside_Allocator : Boolean := False;
1987 P : Node_Id := Parent (N);
1989 begin
1990 if Is_Task_Type (Ctype) or else Has_Task (Ctype) then
1991 while Present (P) loop
1992 if Nkind (P) = N_Allocator then
1993 Inside_Allocator := True;
1994 exit;
1995 end if;
1997 P := Parent (P);
1998 end loop;
2000 if not Inside_Init_Proc and not Inside_Allocator then
2001 Build_Activation_Chain_Entity (N);
2003 if not Has_Master_Entity (Current_Scope) then
2004 Build_Master_Entity (Etype (N));
2005 end if;
2006 end if;
2007 end if;
2008 end;
2010 Append_List_To (L,
2011 Build_Initialization_Call (Loc,
2012 Id_Ref => Make_Selected_Component (Loc,
2013 Prefix => New_Copy_Tree (Target),
2014 Selector_Name => New_Occurrence_Of (Selector,
2015 Loc)),
2016 Typ => Etype (Selector),
2017 With_Default_Init => True));
2019 goto Next_Comp;
2020 end if;
2022 -- ???
2024 if Ekind (Selector) /= E_Discriminant
2025 or else Nkind (N) = N_Extension_Aggregate
2026 then
2027 Comp_Type := Etype (Selector);
2028 Comp_Expr :=
2029 Make_Selected_Component (Loc,
2030 Prefix => New_Copy_Tree (Target),
2031 Selector_Name => New_Occurrence_Of (Selector, Loc));
2033 if Nkind (Expression (Comp)) = N_Qualified_Expression then
2034 Expr_Q := Expression (Expression (Comp));
2035 else
2036 Expr_Q := Expression (Comp);
2037 end if;
2039 -- The controller is the one of the parent type defining
2040 -- the component (in case of inherited components).
2042 if Controlled_Type (Comp_Type) then
2043 Internal_Final_List :=
2044 Make_Selected_Component (Loc,
2045 Prefix => Convert_To (
2046 Scope (Original_Record_Component (Selector)),
2047 New_Copy_Tree (Target)),
2048 Selector_Name =>
2049 Make_Identifier (Loc, Name_uController));
2051 Internal_Final_List :=
2052 Make_Selected_Component (Loc,
2053 Prefix => Internal_Final_List,
2054 Selector_Name => Make_Identifier (Loc, Name_F));
2056 -- The internal final list can be part of a constant object
2058 Set_Assignment_OK (Internal_Final_List);
2060 else
2061 Internal_Final_List := Empty;
2062 end if;
2064 -- ???
2066 if Is_Delayed_Aggregate (Expr_Q) then
2067 Append_List_To (L,
2068 Late_Expansion (Expr_Q, Comp_Type, Comp_Expr,
2069 Internal_Final_List));
2071 else
2072 Instr :=
2073 Make_OK_Assignment_Statement (Loc,
2074 Name => Comp_Expr,
2075 Expression => Expression (Comp));
2077 Set_No_Ctrl_Actions (Instr);
2078 Append_To (L, Instr);
2080 -- Adjust the tag if tagged (because of possible view
2081 -- conversions), unless compiling for the Java VM
2082 -- where tags are implicit.
2084 -- tmp.comp._tag := comp_typ'tag;
2086 if Is_Tagged_Type (Comp_Type) and then not Java_VM then
2087 Instr :=
2088 Make_OK_Assignment_Statement (Loc,
2089 Name =>
2090 Make_Selected_Component (Loc,
2091 Prefix => New_Copy_Tree (Comp_Expr),
2092 Selector_Name =>
2093 New_Reference_To (Tag_Component (Comp_Type), Loc)),
2095 Expression =>
2096 Unchecked_Convert_To (RTE (RE_Tag),
2097 New_Reference_To (
2098 Access_Disp_Table (Comp_Type), Loc)));
2100 Append_To (L, Instr);
2101 end if;
2103 -- Adjust and Attach the component to the proper controller
2104 -- Adjust (tmp.comp);
2105 -- Attach_To_Final_List (tmp.comp,
2106 -- comp_typ (tmp)._record_controller.f)
2108 if Controlled_Type (Comp_Type) then
2109 Append_List_To (L,
2110 Make_Adjust_Call (
2111 Ref => New_Copy_Tree (Comp_Expr),
2112 Typ => Comp_Type,
2113 Flist_Ref => Internal_Final_List,
2114 With_Attach => Make_Integer_Literal (Loc, 1)));
2115 end if;
2116 end if;
2118 -- ???
2120 elsif Ekind (Selector) = E_Discriminant
2121 and then Nkind (N) /= N_Extension_Aggregate
2122 and then Nkind (Parent (N)) = N_Component_Association
2123 and then Is_Constrained (Typ)
2124 then
2125 -- We must check that the discriminant value imposed by the
2126 -- context is the same as the value given in the subaggregate,
2127 -- because after the expansion into assignments there is no
2128 -- record on which to perform a regular discriminant check.
2130 declare
2131 D_Val : Elmt_Id;
2132 Disc : Entity_Id;
2134 begin
2135 D_Val := First_Elmt (Discriminant_Constraint (Typ));
2136 Disc := First_Discriminant (Typ);
2138 while Chars (Disc) /= Chars (Selector) loop
2139 Next_Discriminant (Disc);
2140 Next_Elmt (D_Val);
2141 end loop;
2143 pragma Assert (Present (D_Val));
2145 Append_To (L,
2146 Make_Raise_Constraint_Error (Loc,
2147 Condition =>
2148 Make_Op_Ne (Loc,
2149 Left_Opnd => New_Copy_Tree (Node (D_Val)),
2150 Right_Opnd => Expression (Comp)),
2151 Reason => CE_Discriminant_Check_Failed));
2152 end;
2153 end if;
2155 <<Next_Comp>>
2157 Next (Comp);
2158 end loop;
2160 -- If the type is tagged, the tag needs to be initialized (unless
2161 -- compiling for the Java VM where tags are implicit). It is done
2162 -- late in the initialization process because in some cases, we call
2163 -- the init proc of an ancestor which will not leave out the right tag
2165 if Ancestor_Is_Expression then
2166 null;
2168 elsif Is_Tagged_Type (Typ) and then not Java_VM then
2169 Instr :=
2170 Make_OK_Assignment_Statement (Loc,
2171 Name =>
2172 Make_Selected_Component (Loc,
2173 Prefix => New_Copy_Tree (Target),
2174 Selector_Name =>
2175 New_Reference_To (Tag_Component (Base_Type (Typ)), Loc)),
2177 Expression =>
2178 Unchecked_Convert_To (RTE (RE_Tag),
2179 New_Reference_To (Access_Disp_Table (Base_Type (Typ)), Loc)));
2181 Append_To (L, Instr);
2182 end if;
2184 -- Now deal with the various controlled type data structure
2185 -- initializations
2187 if Present (Obj)
2188 and then Finalize_Storage_Only (Typ)
2189 and then (Is_Library_Level_Entity (Obj)
2190 or else Entity (Constant_Value (RTE (RE_Garbage_Collected)))
2191 = Standard_True)
2192 then
2193 Attach := Make_Integer_Literal (Loc, 0);
2195 elsif Nkind (Parent (N)) = N_Qualified_Expression
2196 and then Nkind (Parent (Parent (N))) = N_Allocator
2197 then
2198 Attach := Make_Integer_Literal (Loc, 2);
2200 else
2201 Attach := Make_Integer_Literal (Loc, 1);
2202 end if;
2204 -- Determine the external finalization list. It is either the
2205 -- finalization list of the outer-scope or the one coming from
2206 -- an outer aggregate. When the target is not a temporary, the
2207 -- proper scope is the scope of the target rather than the
2208 -- potentially transient current scope.
2210 if Controlled_Type (Typ) then
2211 if Present (Flist) then
2212 External_Final_List := New_Copy_Tree (Flist);
2214 elsif Is_Entity_Name (Target)
2215 and then Present (Scope (Entity (Target)))
2216 then
2217 External_Final_List := Find_Final_List (Scope (Entity (Target)));
2219 else
2220 External_Final_List := Find_Final_List (Current_Scope);
2221 end if;
2223 else
2224 External_Final_List := Empty;
2225 end if;
2227 -- Initialize and attach the outer object in the is_controlled case
2229 if Is_Controlled (Typ) then
2230 if Ancestor_Is_Subtype_Mark then
2231 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2232 Set_Assignment_OK (Ref);
2233 Append_To (L,
2234 Make_Procedure_Call_Statement (Loc,
2235 Name => New_Reference_To (
2236 Find_Prim_Op (Init_Typ, Name_Initialize), Loc),
2237 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
2238 end if;
2240 if not Has_Controlled_Component (Typ) then
2241 Ref := New_Copy_Tree (Target);
2242 Set_Assignment_OK (Ref);
2243 Append_To (Start_L,
2244 Make_Attach_Call (
2245 Obj_Ref => Ref,
2246 Flist_Ref => New_Copy_Tree (External_Final_List),
2247 With_Attach => Attach));
2248 end if;
2249 end if;
2251 -- In the Has_Controlled component case, all the intermediate
2252 -- controllers must be initialized
2254 if Has_Controlled_Component (Typ)
2255 and not Is_Limited_Ancestor_Expansion
2256 then
2257 declare
2258 Inner_Typ : Entity_Id;
2259 Outer_Typ : Entity_Id;
2260 At_Root : Boolean;
2262 begin
2264 Outer_Typ := Base_Type (Typ);
2266 -- Find outer type with a controller
2268 while Outer_Typ /= Init_Typ
2269 and then not Has_New_Controlled_Component (Outer_Typ)
2270 loop
2271 Outer_Typ := Etype (Outer_Typ);
2272 end loop;
2274 -- Attach it to the outer record controller to the
2275 -- external final list
2277 if Outer_Typ = Init_Typ then
2278 Append_List_To (Start_L,
2279 Init_Controller (
2280 Target => Target,
2281 Typ => Outer_Typ,
2282 F => External_Final_List,
2283 Attach => Attach,
2284 Init_Pr => Ancestor_Is_Expression));
2286 At_Root := True;
2287 Inner_Typ := Init_Typ;
2289 else
2290 Append_List_To (Start_L,
2291 Init_Controller (
2292 Target => Target,
2293 Typ => Outer_Typ,
2294 F => External_Final_List,
2295 Attach => Attach,
2296 Init_Pr => True));
2298 Inner_Typ := Etype (Outer_Typ);
2299 At_Root :=
2300 not Is_Tagged_Type (Typ) or else Inner_Typ = Outer_Typ;
2301 end if;
2303 -- The outer object has to be attached as well
2305 if Is_Controlled (Typ) then
2306 Ref := New_Copy_Tree (Target);
2307 Set_Assignment_OK (Ref);
2308 Append_To (Start_L,
2309 Make_Attach_Call (
2310 Obj_Ref => Ref,
2311 Flist_Ref => New_Copy_Tree (External_Final_List),
2312 With_Attach => New_Copy_Tree (Attach)));
2313 end if;
2315 -- Initialize the internal controllers for tagged types with
2316 -- more than one controller.
2318 while not At_Root and then Inner_Typ /= Init_Typ loop
2319 if Has_New_Controlled_Component (Inner_Typ) then
2320 F :=
2321 Make_Selected_Component (Loc,
2322 Prefix => Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2323 Selector_Name =>
2324 Make_Identifier (Loc, Name_uController));
2325 F :=
2326 Make_Selected_Component (Loc,
2327 Prefix => F,
2328 Selector_Name => Make_Identifier (Loc, Name_F));
2330 Append_List_To (Start_L,
2331 Init_Controller (
2332 Target => Target,
2333 Typ => Inner_Typ,
2334 F => F,
2335 Attach => Make_Integer_Literal (Loc, 1),
2336 Init_Pr => True));
2337 Outer_Typ := Inner_Typ;
2338 end if;
2340 -- Stop at the root
2342 At_Root := Inner_Typ = Etype (Inner_Typ);
2343 Inner_Typ := Etype (Inner_Typ);
2344 end loop;
2346 -- If not done yet attach the controller of the ancestor part
2348 if Outer_Typ /= Init_Typ
2349 and then Inner_Typ = Init_Typ
2350 and then Has_Controlled_Component (Init_Typ)
2351 then
2352 F :=
2353 Make_Selected_Component (Loc,
2354 Prefix => Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2355 Selector_Name => Make_Identifier (Loc, Name_uController));
2356 F :=
2357 Make_Selected_Component (Loc,
2358 Prefix => F,
2359 Selector_Name => Make_Identifier (Loc, Name_F));
2361 Attach := Make_Integer_Literal (Loc, 1);
2362 Append_List_To (Start_L,
2363 Init_Controller (
2364 Target => Target,
2365 Typ => Init_Typ,
2366 F => F,
2367 Attach => Attach,
2368 Init_Pr => Ancestor_Is_Expression));
2369 end if;
2370 end;
2371 end if;
2373 Append_List_To (Start_L, L);
2374 return Start_L;
2375 end Build_Record_Aggr_Code;
2377 -------------------------------
2378 -- Convert_Aggr_In_Allocator --
2379 -------------------------------
2381 procedure Convert_Aggr_In_Allocator (Decl, Aggr : Node_Id) is
2382 Loc : constant Source_Ptr := Sloc (Aggr);
2383 Typ : constant Entity_Id := Etype (Aggr);
2384 Temp : constant Entity_Id := Defining_Identifier (Decl);
2386 Occ : constant Node_Id :=
2387 Unchecked_Convert_To (Typ,
2388 Make_Explicit_Dereference (Loc,
2389 New_Reference_To (Temp, Loc)));
2391 Access_Type : constant Entity_Id := Etype (Temp);
2393 begin
2394 if Is_Array_Type (Typ) then
2395 Convert_Array_Aggr_In_Allocator (Decl, Aggr, Occ);
2397 elsif Has_Default_Init_Comps (Aggr) then
2398 declare
2399 L : constant List_Id := New_List;
2400 Init_Stmts : List_Id;
2402 begin
2403 Init_Stmts := Late_Expansion (Aggr, Typ, Occ,
2404 Find_Final_List (Access_Type),
2405 Associated_Final_Chain (Base_Type (Access_Type)));
2407 Build_Task_Allocate_Block_With_Init_Stmts (L, Aggr, Init_Stmts);
2408 Insert_Actions_After (Decl, L);
2409 end;
2411 else
2412 Insert_Actions_After (Decl,
2413 Late_Expansion (Aggr, Typ, Occ,
2414 Find_Final_List (Access_Type),
2415 Associated_Final_Chain (Base_Type (Access_Type))));
2416 end if;
2417 end Convert_Aggr_In_Allocator;
2419 --------------------------------
2420 -- Convert_Aggr_In_Assignment --
2421 --------------------------------
2423 procedure Convert_Aggr_In_Assignment (N : Node_Id) is
2424 Aggr : Node_Id := Expression (N);
2425 Typ : constant Entity_Id := Etype (Aggr);
2426 Occ : constant Node_Id := New_Copy_Tree (Name (N));
2428 begin
2429 if Nkind (Aggr) = N_Qualified_Expression then
2430 Aggr := Expression (Aggr);
2431 end if;
2433 Insert_Actions_After (N,
2434 Late_Expansion (Aggr, Typ, Occ,
2435 Find_Final_List (Typ, New_Copy_Tree (Occ))));
2436 end Convert_Aggr_In_Assignment;
2438 ---------------------------------
2439 -- Convert_Aggr_In_Object_Decl --
2440 ---------------------------------
2442 procedure Convert_Aggr_In_Object_Decl (N : Node_Id) is
2443 Obj : constant Entity_Id := Defining_Identifier (N);
2444 Aggr : Node_Id := Expression (N);
2445 Loc : constant Source_Ptr := Sloc (Aggr);
2446 Typ : constant Entity_Id := Etype (Aggr);
2447 Occ : constant Node_Id := New_Occurrence_Of (Obj, Loc);
2449 function Discriminants_Ok return Boolean;
2450 -- If the object type is constrained, the discriminants in the
2451 -- aggregate must be checked against the discriminants of the subtype.
2452 -- This cannot be done using Apply_Discriminant_Checks because after
2453 -- expansion there is no aggregate left to check.
2455 ----------------------
2456 -- Discriminants_Ok --
2457 ----------------------
2459 function Discriminants_Ok return Boolean is
2460 Cond : Node_Id := Empty;
2461 Check : Node_Id;
2462 D : Entity_Id;
2463 Disc1 : Elmt_Id;
2464 Disc2 : Elmt_Id;
2465 Val1 : Node_Id;
2466 Val2 : Node_Id;
2468 begin
2469 D := First_Discriminant (Typ);
2470 Disc1 := First_Elmt (Discriminant_Constraint (Typ));
2471 Disc2 := First_Elmt (Discriminant_Constraint (Etype (Obj)));
2473 while Present (Disc1) and then Present (Disc2) loop
2474 Val1 := Node (Disc1);
2475 Val2 := Node (Disc2);
2477 if not Is_OK_Static_Expression (Val1)
2478 or else not Is_OK_Static_Expression (Val2)
2479 then
2480 Check := Make_Op_Ne (Loc,
2481 Left_Opnd => Duplicate_Subexpr (Val1),
2482 Right_Opnd => Duplicate_Subexpr (Val2));
2484 if No (Cond) then
2485 Cond := Check;
2487 else
2488 Cond := Make_Or_Else (Loc,
2489 Left_Opnd => Cond,
2490 Right_Opnd => Check);
2491 end if;
2493 elsif Expr_Value (Val1) /= Expr_Value (Val2) then
2494 Apply_Compile_Time_Constraint_Error (Aggr,
2495 Msg => "incorrect value for discriminant&?",
2496 Reason => CE_Discriminant_Check_Failed,
2497 Ent => D);
2498 return False;
2499 end if;
2501 Next_Discriminant (D);
2502 Next_Elmt (Disc1);
2503 Next_Elmt (Disc2);
2504 end loop;
2506 -- If any discriminant constraint is non-static, emit a check
2508 if Present (Cond) then
2509 Insert_Action (N,
2510 Make_Raise_Constraint_Error (Loc,
2511 Condition => Cond,
2512 Reason => CE_Discriminant_Check_Failed));
2513 end if;
2515 return True;
2516 end Discriminants_Ok;
2518 -- Start of processing for Convert_Aggr_In_Object_Decl
2520 begin
2521 Set_Assignment_OK (Occ);
2523 if Nkind (Aggr) = N_Qualified_Expression then
2524 Aggr := Expression (Aggr);
2525 end if;
2527 if Has_Discriminants (Typ)
2528 and then Typ /= Etype (Obj)
2529 and then Is_Constrained (Etype (Obj))
2530 and then not Discriminants_Ok
2531 then
2532 return;
2533 end if;
2535 Insert_Actions_After (N, Late_Expansion (Aggr, Typ, Occ, Obj => Obj));
2536 Set_No_Initialization (N);
2537 Initialize_Discriminants (N, Typ);
2538 end Convert_Aggr_In_Object_Decl;
2540 -------------------------------------
2541 -- Convert_array_Aggr_In_Allocator --
2542 -------------------------------------
2544 procedure Convert_Array_Aggr_In_Allocator
2545 (Decl : Node_Id;
2546 Aggr : Node_Id;
2547 Target : Node_Id)
2549 Aggr_Code : List_Id;
2550 Typ : constant Entity_Id := Etype (Aggr);
2551 Ctyp : constant Entity_Id := Component_Type (Typ);
2553 begin
2554 -- The target is an explicit dereference of the allocated object.
2555 -- Generate component assignments to it, as for an aggregate that
2556 -- appears on the right-hand side of an assignment statement.
2558 Aggr_Code :=
2559 Build_Array_Aggr_Code (Aggr,
2560 Ctype => Ctyp,
2561 Index => First_Index (Typ),
2562 Into => Target,
2563 Scalar_Comp => Is_Scalar_Type (Ctyp));
2565 Insert_Actions_After (Decl, Aggr_Code);
2566 end Convert_Array_Aggr_In_Allocator;
2568 ----------------------------
2569 -- Convert_To_Assignments --
2570 ----------------------------
2572 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id) is
2573 Loc : constant Source_Ptr := Sloc (N);
2574 Temp : Entity_Id;
2576 Instr : Node_Id;
2577 Target_Expr : Node_Id;
2578 Parent_Kind : Node_Kind;
2579 Unc_Decl : Boolean := False;
2580 Parent_Node : Node_Id;
2582 begin
2583 Parent_Node := Parent (N);
2584 Parent_Kind := Nkind (Parent_Node);
2586 if Parent_Kind = N_Qualified_Expression then
2588 -- Check if we are in a unconstrained declaration because in this
2589 -- case the current delayed expansion mechanism doesn't work when
2590 -- the declared object size depend on the initializing expr.
2592 begin
2593 Parent_Node := Parent (Parent_Node);
2594 Parent_Kind := Nkind (Parent_Node);
2596 if Parent_Kind = N_Object_Declaration then
2597 Unc_Decl :=
2598 not Is_Entity_Name (Object_Definition (Parent_Node))
2599 or else Has_Discriminants
2600 (Entity (Object_Definition (Parent_Node)))
2601 or else Is_Class_Wide_Type
2602 (Entity (Object_Definition (Parent_Node)));
2603 end if;
2604 end;
2605 end if;
2607 -- Just set the Delay flag in the following cases where the
2608 -- transformation will be done top down from above
2610 -- - internal aggregate (transformed when expanding the parent)
2611 -- - allocators (see Convert_Aggr_In_Allocator)
2612 -- - object decl (see Convert_Aggr_In_Object_Decl)
2613 -- - safe assignments (see Convert_Aggr_Assignments)
2614 -- so far only the assignments in the init procs are taken
2615 -- into account
2617 if Parent_Kind = N_Aggregate
2618 or else Parent_Kind = N_Extension_Aggregate
2619 or else Parent_Kind = N_Component_Association
2620 or else Parent_Kind = N_Allocator
2621 or else (Parent_Kind = N_Object_Declaration and then not Unc_Decl)
2622 or else (Parent_Kind = N_Assignment_Statement
2623 and then Inside_Init_Proc)
2624 then
2625 Set_Expansion_Delayed (N);
2626 return;
2627 end if;
2629 if Requires_Transient_Scope (Typ) then
2630 Establish_Transient_Scope (N, Sec_Stack =>
2631 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
2632 end if;
2634 -- Create the temporary
2636 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
2638 Instr :=
2639 Make_Object_Declaration (Loc,
2640 Defining_Identifier => Temp,
2641 Object_Definition => New_Occurrence_Of (Typ, Loc));
2643 Set_No_Initialization (Instr);
2644 Insert_Action (N, Instr);
2645 Initialize_Discriminants (Instr, Typ);
2646 Target_Expr := New_Occurrence_Of (Temp, Loc);
2648 Insert_Actions (N, Build_Record_Aggr_Code (N, Typ, Target_Expr));
2649 Rewrite (N, New_Occurrence_Of (Temp, Loc));
2650 Analyze_And_Resolve (N, Typ);
2651 end Convert_To_Assignments;
2653 ---------------------------
2654 -- Convert_To_Positional --
2655 ---------------------------
2657 procedure Convert_To_Positional
2658 (N : Node_Id;
2659 Max_Others_Replicate : Nat := 5;
2660 Handle_Bit_Packed : Boolean := False)
2662 Typ : constant Entity_Id := Etype (N);
2664 function Flatten
2665 (N : Node_Id;
2666 Ix : Node_Id;
2667 Ixb : Node_Id) return Boolean;
2668 -- Convert the aggregate into a purely positional form if possible
2670 function Is_Flat (N : Node_Id; Dims : Int) return Boolean;
2671 -- Return True iff the array N is flat (which is not rivial
2672 -- in the case of multidimensionsl aggregates).
2674 -------------
2675 -- Flatten --
2676 -------------
2678 function Flatten
2679 (N : Node_Id;
2680 Ix : Node_Id;
2681 Ixb : Node_Id) return Boolean
2683 Loc : constant Source_Ptr := Sloc (N);
2684 Blo : constant Node_Id := Type_Low_Bound (Etype (Ixb));
2685 Lo : constant Node_Id := Type_Low_Bound (Etype (Ix));
2686 Hi : constant Node_Id := Type_High_Bound (Etype (Ix));
2687 Lov : Uint;
2688 Hiv : Uint;
2690 -- The following constant determines the maximum size of an
2691 -- aggregate produced by converting named to positional
2692 -- notation (e.g. from others clauses). This avoids running
2693 -- away with attempts to convert huge aggregates.
2695 -- The normal limit is 5000, but we increase this limit to
2696 -- 2**24 (about 16 million) if Restrictions (No_Elaboration_Code)
2697 -- or Restrictions (No_Implicit_Loops) is specified, since in
2698 -- either case, we are at risk of declaring the program illegal
2699 -- because of this limit.
2701 Max_Aggr_Size : constant Nat :=
2702 5000 + (2 ** 24 - 5000) *
2703 Boolean'Pos
2704 (Restriction_Active (No_Elaboration_Code)
2705 or else
2706 Restriction_Active (No_Implicit_Loops));
2708 begin
2709 if Nkind (Original_Node (N)) = N_String_Literal then
2710 return True;
2711 end if;
2713 -- Bounds need to be known at compile time
2715 if not Compile_Time_Known_Value (Lo)
2716 or else not Compile_Time_Known_Value (Hi)
2717 then
2718 return False;
2719 end if;
2721 -- Get bounds and check reasonable size (positive, not too large)
2722 -- Also only handle bounds starting at the base type low bound
2723 -- for now since the compiler isn't able to handle different low
2724 -- bounds yet. Case such as new String'(3..5 => ' ') will get
2725 -- the wrong bounds, though it seems that the aggregate should
2726 -- retain the bounds set on its Etype (see C64103E and CC1311B).
2728 Lov := Expr_Value (Lo);
2729 Hiv := Expr_Value (Hi);
2731 if Hiv < Lov
2732 or else (Hiv - Lov > Max_Aggr_Size)
2733 or else not Compile_Time_Known_Value (Blo)
2734 or else (Lov /= Expr_Value (Blo))
2735 then
2736 return False;
2737 end if;
2739 -- Bounds must be in integer range (for array Vals below)
2741 if not UI_Is_In_Int_Range (Lov)
2742 or else
2743 not UI_Is_In_Int_Range (Hiv)
2744 then
2745 return False;
2746 end if;
2748 -- Determine if set of alternatives is suitable for conversion
2749 -- and build an array containing the values in sequence.
2751 declare
2752 Vals : array (UI_To_Int (Lov) .. UI_To_Int (Hiv))
2753 of Node_Id := (others => Empty);
2754 -- The values in the aggregate sorted appropriately
2756 Vlist : List_Id;
2757 -- Same data as Vals in list form
2759 Rep_Count : Nat;
2760 -- Used to validate Max_Others_Replicate limit
2762 Elmt : Node_Id;
2763 Num : Int := UI_To_Int (Lov);
2764 Choice : Node_Id;
2765 Lo, Hi : Node_Id;
2767 begin
2768 if Present (Expressions (N)) then
2769 Elmt := First (Expressions (N));
2771 while Present (Elmt) loop
2772 if Nkind (Elmt) = N_Aggregate
2773 and then Present (Next_Index (Ix))
2774 and then
2775 not Flatten (Elmt, Next_Index (Ix), Next_Index (Ixb))
2776 then
2777 return False;
2778 end if;
2780 Vals (Num) := Relocate_Node (Elmt);
2781 Num := Num + 1;
2783 Next (Elmt);
2784 end loop;
2785 end if;
2787 if No (Component_Associations (N)) then
2788 return True;
2789 end if;
2791 Elmt := First (Component_Associations (N));
2793 if Nkind (Expression (Elmt)) = N_Aggregate then
2794 if Present (Next_Index (Ix))
2795 and then
2796 not Flatten
2797 (Expression (Elmt), Next_Index (Ix), Next_Index (Ixb))
2798 then
2799 return False;
2800 end if;
2801 end if;
2803 Component_Loop : while Present (Elmt) loop
2804 Choice := First (Choices (Elmt));
2805 Choice_Loop : while Present (Choice) loop
2807 -- If we have an others choice, fill in the missing elements
2808 -- subject to the limit established by Max_Others_Replicate.
2810 if Nkind (Choice) = N_Others_Choice then
2811 Rep_Count := 0;
2813 for J in Vals'Range loop
2814 if No (Vals (J)) then
2815 Vals (J) := New_Copy_Tree (Expression (Elmt));
2816 Rep_Count := Rep_Count + 1;
2818 -- Check for maximum others replication. Note that
2819 -- we skip this test if either of the restrictions
2820 -- No_Elaboration_Code or No_Implicit_Loops is
2821 -- active, or if this is a preelaborable unit.
2823 declare
2824 P : constant Entity_Id :=
2825 Cunit_Entity (Current_Sem_Unit);
2827 begin
2828 if Restriction_Active (No_Elaboration_Code)
2829 or else Restriction_Active (No_Implicit_Loops)
2830 or else Is_Preelaborated (P)
2831 or else (Ekind (P) = E_Package_Body
2832 and then
2833 Is_Preelaborated (Spec_Entity (P)))
2834 then
2835 null;
2837 elsif Rep_Count > Max_Others_Replicate then
2838 return False;
2839 end if;
2840 end;
2841 end if;
2842 end loop;
2844 exit Component_Loop;
2846 -- Case of a subtype mark
2848 elsif Nkind (Choice) = N_Identifier
2849 and then Is_Type (Entity (Choice))
2850 then
2851 Lo := Type_Low_Bound (Etype (Choice));
2852 Hi := Type_High_Bound (Etype (Choice));
2854 -- Case of subtype indication
2856 elsif Nkind (Choice) = N_Subtype_Indication then
2857 Lo := Low_Bound (Range_Expression (Constraint (Choice)));
2858 Hi := High_Bound (Range_Expression (Constraint (Choice)));
2860 -- Case of a range
2862 elsif Nkind (Choice) = N_Range then
2863 Lo := Low_Bound (Choice);
2864 Hi := High_Bound (Choice);
2866 -- Normal subexpression case
2868 else pragma Assert (Nkind (Choice) in N_Subexpr);
2869 if not Compile_Time_Known_Value (Choice) then
2870 return False;
2872 else
2873 Vals (UI_To_Int (Expr_Value (Choice))) :=
2874 New_Copy_Tree (Expression (Elmt));
2875 goto Continue;
2876 end if;
2877 end if;
2879 -- Range cases merge with Lo,Hi said
2881 if not Compile_Time_Known_Value (Lo)
2882 or else
2883 not Compile_Time_Known_Value (Hi)
2884 then
2885 return False;
2886 else
2887 for J in UI_To_Int (Expr_Value (Lo)) ..
2888 UI_To_Int (Expr_Value (Hi))
2889 loop
2890 Vals (J) := New_Copy_Tree (Expression (Elmt));
2891 end loop;
2892 end if;
2894 <<Continue>>
2895 Next (Choice);
2896 end loop Choice_Loop;
2898 Next (Elmt);
2899 end loop Component_Loop;
2901 -- If we get here the conversion is possible
2903 Vlist := New_List;
2904 for J in Vals'Range loop
2905 Append (Vals (J), Vlist);
2906 end loop;
2908 Rewrite (N, Make_Aggregate (Loc, Expressions => Vlist));
2909 Set_Aggregate_Bounds (N, Aggregate_Bounds (Original_Node (N)));
2910 return True;
2911 end;
2912 end Flatten;
2914 -------------
2915 -- Is_Flat --
2916 -------------
2918 function Is_Flat (N : Node_Id; Dims : Int) return Boolean is
2919 Elmt : Node_Id;
2921 begin
2922 if Dims = 0 then
2923 return True;
2925 elsif Nkind (N) = N_Aggregate then
2926 if Present (Component_Associations (N)) then
2927 return False;
2929 else
2930 Elmt := First (Expressions (N));
2932 while Present (Elmt) loop
2933 if not Is_Flat (Elmt, Dims - 1) then
2934 return False;
2935 end if;
2937 Next (Elmt);
2938 end loop;
2940 return True;
2941 end if;
2942 else
2943 return True;
2944 end if;
2945 end Is_Flat;
2947 -- Start of processing for Convert_To_Positional
2949 begin
2950 -- Ada 2005 (AI-287): Do not convert in case of default initialized
2951 -- components because in this case will need to call the corresponding
2952 -- IP procedure.
2954 if Has_Default_Init_Comps (N) then
2955 return;
2956 end if;
2958 if Is_Flat (N, Number_Dimensions (Typ)) then
2959 return;
2960 end if;
2962 if Is_Bit_Packed_Array (Typ)
2963 and then not Handle_Bit_Packed
2964 then
2965 return;
2966 end if;
2968 -- Do not convert to positional if controlled components are
2969 -- involved since these require special processing
2971 if Has_Controlled_Component (Typ) then
2972 return;
2973 end if;
2975 if Flatten (N, First_Index (Typ), First_Index (Base_Type (Typ))) then
2976 Analyze_And_Resolve (N, Typ);
2977 end if;
2978 end Convert_To_Positional;
2980 ----------------------------
2981 -- Expand_Array_Aggregate --
2982 ----------------------------
2984 -- Array aggregate expansion proceeds as follows:
2986 -- 1. If requested we generate code to perform all the array aggregate
2987 -- bound checks, specifically
2989 -- (a) Check that the index range defined by aggregate bounds is
2990 -- compatible with corresponding index subtype.
2992 -- (b) If an others choice is present check that no aggregate
2993 -- index is outside the bounds of the index constraint.
2995 -- (c) For multidimensional arrays make sure that all subaggregates
2996 -- corresponding to the same dimension have the same bounds.
2998 -- 2. Check for packed array aggregate which can be converted to a
2999 -- constant so that the aggregate disappeares completely.
3001 -- 3. Check case of nested aggregate. Generally nested aggregates are
3002 -- handled during the processing of the parent aggregate.
3004 -- 4. Check if the aggregate can be statically processed. If this is the
3005 -- case pass it as is to Gigi. Note that a necessary condition for
3006 -- static processing is that the aggregate be fully positional.
3008 -- 5. If in place aggregate expansion is possible (i.e. no need to create
3009 -- a temporary) then mark the aggregate as such and return. Otherwise
3010 -- create a new temporary and generate the appropriate initialization
3011 -- code.
3013 procedure Expand_Array_Aggregate (N : Node_Id) is
3014 Loc : constant Source_Ptr := Sloc (N);
3016 Typ : constant Entity_Id := Etype (N);
3017 Ctyp : constant Entity_Id := Component_Type (Typ);
3018 -- Typ is the correct constrained array subtype of the aggregate
3019 -- Ctyp is the corresponding component type.
3021 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
3022 -- Number of aggregate index dimensions
3024 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id;
3025 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id;
3026 -- Low and High bounds of the constraint for each aggregate index
3028 Aggr_Index_Typ : array (1 .. Aggr_Dimension) of Entity_Id;
3029 -- The type of each index
3031 Maybe_In_Place_OK : Boolean;
3032 -- If the type is neither controlled nor packed and the aggregate
3033 -- is the expression in an assignment, assignment in place may be
3034 -- possible, provided other conditions are met on the LHS.
3036 Others_Present : array (1 .. Aggr_Dimension) of Boolean :=
3037 (others => False);
3038 -- If Others_Present (J) is True, then there is an others choice
3039 -- in one of the sub-aggregates of N at dimension J.
3041 procedure Build_Constrained_Type (Positional : Boolean);
3042 -- If the subtype is not static or unconstrained, build a constrained
3043 -- type using the computable sizes of the aggregate and its sub-
3044 -- aggregates.
3046 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id);
3047 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
3048 -- by Index_Bounds.
3050 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos);
3051 -- Checks that in a multi-dimensional array aggregate all subaggregates
3052 -- corresponding to the same dimension have the same bounds.
3053 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
3054 -- corresponding to the sub-aggregate.
3056 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos);
3057 -- Computes the values of array Others_Present. Sub_Aggr is the
3058 -- array sub-aggregate we start the computation from. Dim is the
3059 -- dimension corresponding to the sub-aggregate.
3061 function Has_Address_Clause (D : Node_Id) return Boolean;
3062 -- If the aggregate is the expression in an object declaration, it
3063 -- cannot be expanded in place. This function does a lookahead in the
3064 -- current declarative part to find an address clause for the object
3065 -- being declared.
3067 function In_Place_Assign_OK return Boolean;
3068 -- Simple predicate to determine whether an aggregate assignment can
3069 -- be done in place, because none of the new values can depend on the
3070 -- components of the target of the assignment.
3072 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos);
3073 -- Checks that if an others choice is present in any sub-aggregate no
3074 -- aggregate index is outside the bounds of the index constraint.
3075 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
3076 -- corresponding to the sub-aggregate.
3078 ----------------------------
3079 -- Build_Constrained_Type --
3080 ----------------------------
3082 procedure Build_Constrained_Type (Positional : Boolean) is
3083 Loc : constant Source_Ptr := Sloc (N);
3084 Agg_Type : Entity_Id;
3085 Comp : Node_Id;
3086 Decl : Node_Id;
3087 Typ : constant Entity_Id := Etype (N);
3088 Indices : constant List_Id := New_List;
3089 Num : Int;
3090 Sub_Agg : Node_Id;
3092 begin
3093 Agg_Type :=
3094 Make_Defining_Identifier (
3095 Loc, New_Internal_Name ('A'));
3097 -- If the aggregate is purely positional, all its subaggregates
3098 -- have the same size. We collect the dimensions from the first
3099 -- subaggregate at each level.
3101 if Positional then
3102 Sub_Agg := N;
3104 for D in 1 .. Number_Dimensions (Typ) loop
3105 Comp := First (Expressions (Sub_Agg));
3107 Sub_Agg := Comp;
3108 Num := 0;
3110 while Present (Comp) loop
3111 Num := Num + 1;
3112 Next (Comp);
3113 end loop;
3115 Append (
3116 Make_Range (Loc,
3117 Low_Bound => Make_Integer_Literal (Loc, 1),
3118 High_Bound =>
3119 Make_Integer_Literal (Loc, Num)),
3120 Indices);
3121 end loop;
3123 else
3124 -- We know the aggregate type is unconstrained and the
3125 -- aggregate is not processable by the back end, therefore
3126 -- not necessarily positional. Retrieve the bounds of each
3127 -- dimension as computed earlier.
3129 for D in 1 .. Number_Dimensions (Typ) loop
3130 Append (
3131 Make_Range (Loc,
3132 Low_Bound => Aggr_Low (D),
3133 High_Bound => Aggr_High (D)),
3134 Indices);
3135 end loop;
3136 end if;
3138 Decl :=
3139 Make_Full_Type_Declaration (Loc,
3140 Defining_Identifier => Agg_Type,
3141 Type_Definition =>
3142 Make_Constrained_Array_Definition (Loc,
3143 Discrete_Subtype_Definitions => Indices,
3144 Component_Definition =>
3145 Make_Component_Definition (Loc,
3146 Aliased_Present => False,
3147 Subtype_Indication =>
3148 New_Occurrence_Of (Component_Type (Typ), Loc))));
3150 Insert_Action (N, Decl);
3151 Analyze (Decl);
3152 Set_Etype (N, Agg_Type);
3153 Set_Is_Itype (Agg_Type);
3154 Freeze_Itype (Agg_Type, N);
3155 end Build_Constrained_Type;
3157 ------------------
3158 -- Check_Bounds --
3159 ------------------
3161 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id) is
3162 Aggr_Lo : Node_Id;
3163 Aggr_Hi : Node_Id;
3165 Ind_Lo : Node_Id;
3166 Ind_Hi : Node_Id;
3168 Cond : Node_Id := Empty;
3170 begin
3171 Get_Index_Bounds (Aggr_Bounds, Aggr_Lo, Aggr_Hi);
3172 Get_Index_Bounds (Index_Bounds, Ind_Lo, Ind_Hi);
3174 -- Generate the following test:
3176 -- [constraint_error when
3177 -- Aggr_Lo <= Aggr_Hi and then
3178 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
3180 -- As an optimization try to see if some tests are trivially vacuos
3181 -- because we are comparing an expression against itself.
3183 if Aggr_Lo = Ind_Lo and then Aggr_Hi = Ind_Hi then
3184 Cond := Empty;
3186 elsif Aggr_Hi = Ind_Hi then
3187 Cond :=
3188 Make_Op_Lt (Loc,
3189 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3190 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo));
3192 elsif Aggr_Lo = Ind_Lo then
3193 Cond :=
3194 Make_Op_Gt (Loc,
3195 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
3196 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Hi));
3198 else
3199 Cond :=
3200 Make_Or_Else (Loc,
3201 Left_Opnd =>
3202 Make_Op_Lt (Loc,
3203 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3204 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo)),
3206 Right_Opnd =>
3207 Make_Op_Gt (Loc,
3208 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
3209 Right_Opnd => Duplicate_Subexpr (Ind_Hi)));
3210 end if;
3212 if Present (Cond) then
3213 Cond :=
3214 Make_And_Then (Loc,
3215 Left_Opnd =>
3216 Make_Op_Le (Loc,
3217 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3218 Right_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi)),
3220 Right_Opnd => Cond);
3222 Set_Analyzed (Left_Opnd (Left_Opnd (Cond)), False);
3223 Set_Analyzed (Right_Opnd (Left_Opnd (Cond)), False);
3224 Insert_Action (N,
3225 Make_Raise_Constraint_Error (Loc,
3226 Condition => Cond,
3227 Reason => CE_Length_Check_Failed));
3228 end if;
3229 end Check_Bounds;
3231 ----------------------------
3232 -- Check_Same_Aggr_Bounds --
3233 ----------------------------
3235 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos) is
3236 Sub_Lo : constant Node_Id := Low_Bound (Aggregate_Bounds (Sub_Aggr));
3237 Sub_Hi : constant Node_Id := High_Bound (Aggregate_Bounds (Sub_Aggr));
3238 -- The bounds of this specific sub-aggregate
3240 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
3241 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
3242 -- The bounds of the aggregate for this dimension
3244 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
3245 -- The index type for this dimension.xxx
3247 Cond : Node_Id := Empty;
3249 Assoc : Node_Id;
3250 Expr : Node_Id;
3252 begin
3253 -- If index checks are on generate the test
3255 -- [constraint_error when
3256 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
3258 -- As an optimization try to see if some tests are trivially vacuos
3259 -- because we are comparing an expression against itself. Also for
3260 -- the first dimension the test is trivially vacuous because there
3261 -- is just one aggregate for dimension 1.
3263 if Index_Checks_Suppressed (Ind_Typ) then
3264 Cond := Empty;
3266 elsif Dim = 1
3267 or else (Aggr_Lo = Sub_Lo and then Aggr_Hi = Sub_Hi)
3268 then
3269 Cond := Empty;
3271 elsif Aggr_Hi = Sub_Hi then
3272 Cond :=
3273 Make_Op_Ne (Loc,
3274 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3275 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo));
3277 elsif Aggr_Lo = Sub_Lo then
3278 Cond :=
3279 Make_Op_Ne (Loc,
3280 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
3281 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Hi));
3283 else
3284 Cond :=
3285 Make_Or_Else (Loc,
3286 Left_Opnd =>
3287 Make_Op_Ne (Loc,
3288 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3289 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo)),
3291 Right_Opnd =>
3292 Make_Op_Ne (Loc,
3293 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
3294 Right_Opnd => Duplicate_Subexpr (Sub_Hi)));
3295 end if;
3297 if Present (Cond) then
3298 Insert_Action (N,
3299 Make_Raise_Constraint_Error (Loc,
3300 Condition => Cond,
3301 Reason => CE_Length_Check_Failed));
3302 end if;
3304 -- Now look inside the sub-aggregate to see if there is more work
3306 if Dim < Aggr_Dimension then
3308 -- Process positional components
3310 if Present (Expressions (Sub_Aggr)) then
3311 Expr := First (Expressions (Sub_Aggr));
3312 while Present (Expr) loop
3313 Check_Same_Aggr_Bounds (Expr, Dim + 1);
3314 Next (Expr);
3315 end loop;
3316 end if;
3318 -- Process component associations
3320 if Present (Component_Associations (Sub_Aggr)) then
3321 Assoc := First (Component_Associations (Sub_Aggr));
3322 while Present (Assoc) loop
3323 Expr := Expression (Assoc);
3324 Check_Same_Aggr_Bounds (Expr, Dim + 1);
3325 Next (Assoc);
3326 end loop;
3327 end if;
3328 end if;
3329 end Check_Same_Aggr_Bounds;
3331 ----------------------------
3332 -- Compute_Others_Present --
3333 ----------------------------
3335 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos) is
3336 Assoc : Node_Id;
3337 Expr : Node_Id;
3339 begin
3340 if Present (Component_Associations (Sub_Aggr)) then
3341 Assoc := Last (Component_Associations (Sub_Aggr));
3343 if Nkind (First (Choices (Assoc))) = N_Others_Choice then
3344 Others_Present (Dim) := True;
3345 end if;
3346 end if;
3348 -- Now look inside the sub-aggregate to see if there is more work
3350 if Dim < Aggr_Dimension then
3352 -- Process positional components
3354 if Present (Expressions (Sub_Aggr)) then
3355 Expr := First (Expressions (Sub_Aggr));
3356 while Present (Expr) loop
3357 Compute_Others_Present (Expr, Dim + 1);
3358 Next (Expr);
3359 end loop;
3360 end if;
3362 -- Process component associations
3364 if Present (Component_Associations (Sub_Aggr)) then
3365 Assoc := First (Component_Associations (Sub_Aggr));
3366 while Present (Assoc) loop
3367 Expr := Expression (Assoc);
3368 Compute_Others_Present (Expr, Dim + 1);
3369 Next (Assoc);
3370 end loop;
3371 end if;
3372 end if;
3373 end Compute_Others_Present;
3375 ------------------------
3376 -- Has_Address_Clause --
3377 ------------------------
3379 function Has_Address_Clause (D : Node_Id) return Boolean is
3380 Id : constant Entity_Id := Defining_Identifier (D);
3381 Decl : Node_Id := Next (D);
3383 begin
3384 while Present (Decl) loop
3385 if Nkind (Decl) = N_At_Clause
3386 and then Chars (Identifier (Decl)) = Chars (Id)
3387 then
3388 return True;
3390 elsif Nkind (Decl) = N_Attribute_Definition_Clause
3391 and then Chars (Decl) = Name_Address
3392 and then Chars (Name (Decl)) = Chars (Id)
3393 then
3394 return True;
3395 end if;
3397 Next (Decl);
3398 end loop;
3400 return False;
3401 end Has_Address_Clause;
3403 ------------------------
3404 -- In_Place_Assign_OK --
3405 ------------------------
3407 function In_Place_Assign_OK return Boolean is
3408 Aggr_In : Node_Id;
3409 Aggr_Lo : Node_Id;
3410 Aggr_Hi : Node_Id;
3411 Obj_In : Node_Id;
3412 Obj_Lo : Node_Id;
3413 Obj_Hi : Node_Id;
3415 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean;
3416 -- Aggregates that consist of a single Others choice are safe
3417 -- if the single expression is.
3419 function Safe_Aggregate (Aggr : Node_Id) return Boolean;
3420 -- Check recursively that each component of a (sub)aggregate does
3421 -- not depend on the variable being assigned to.
3423 function Safe_Component (Expr : Node_Id) return Boolean;
3424 -- Verify that an expression cannot depend on the variable being
3425 -- assigned to. Room for improvement here (but less than before).
3427 -------------------------
3428 -- Is_Others_Aggregate --
3429 -------------------------
3431 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean is
3432 begin
3433 return No (Expressions (Aggr))
3434 and then Nkind
3435 (First (Choices (First (Component_Associations (Aggr)))))
3436 = N_Others_Choice;
3437 end Is_Others_Aggregate;
3439 --------------------
3440 -- Safe_Aggregate --
3441 --------------------
3443 function Safe_Aggregate (Aggr : Node_Id) return Boolean is
3444 Expr : Node_Id;
3446 begin
3447 if Present (Expressions (Aggr)) then
3448 Expr := First (Expressions (Aggr));
3450 while Present (Expr) loop
3451 if Nkind (Expr) = N_Aggregate then
3452 if not Safe_Aggregate (Expr) then
3453 return False;
3454 end if;
3456 elsif not Safe_Component (Expr) then
3457 return False;
3458 end if;
3460 Next (Expr);
3461 end loop;
3462 end if;
3464 if Present (Component_Associations (Aggr)) then
3465 Expr := First (Component_Associations (Aggr));
3467 while Present (Expr) loop
3468 if Nkind (Expression (Expr)) = N_Aggregate then
3469 if not Safe_Aggregate (Expression (Expr)) then
3470 return False;
3471 end if;
3473 elsif not Safe_Component (Expression (Expr)) then
3474 return False;
3475 end if;
3477 Next (Expr);
3478 end loop;
3479 end if;
3481 return True;
3482 end Safe_Aggregate;
3484 --------------------
3485 -- Safe_Component --
3486 --------------------
3488 function Safe_Component (Expr : Node_Id) return Boolean is
3489 Comp : Node_Id := Expr;
3491 function Check_Component (Comp : Node_Id) return Boolean;
3492 -- Do the recursive traversal, after copy
3494 ---------------------
3495 -- Check_Component --
3496 ---------------------
3498 function Check_Component (Comp : Node_Id) return Boolean is
3499 begin
3500 if Is_Overloaded (Comp) then
3501 return False;
3502 end if;
3504 return Compile_Time_Known_Value (Comp)
3506 or else (Is_Entity_Name (Comp)
3507 and then Present (Entity (Comp))
3508 and then No (Renamed_Object (Entity (Comp))))
3510 or else (Nkind (Comp) = N_Attribute_Reference
3511 and then Check_Component (Prefix (Comp)))
3513 or else (Nkind (Comp) in N_Binary_Op
3514 and then Check_Component (Left_Opnd (Comp))
3515 and then Check_Component (Right_Opnd (Comp)))
3517 or else (Nkind (Comp) in N_Unary_Op
3518 and then Check_Component (Right_Opnd (Comp)))
3520 or else (Nkind (Comp) = N_Selected_Component
3521 and then Check_Component (Prefix (Comp)))
3523 or else (Nkind (Comp) = N_Unchecked_Type_Conversion
3524 and then Check_Component (Expression (Comp)));
3525 end Check_Component;
3527 -- Start of processing for Safe_Component
3529 begin
3530 -- If the component appears in an association that may
3531 -- correspond to more than one element, it is not analyzed
3532 -- before the expansion into assignments, to avoid side effects.
3533 -- We analyze, but do not resolve the copy, to obtain sufficient
3534 -- entity information for the checks that follow. If component is
3535 -- overloaded we assume an unsafe function call.
3537 if not Analyzed (Comp) then
3538 if Is_Overloaded (Expr) then
3539 return False;
3541 elsif Nkind (Expr) = N_Aggregate
3542 and then not Is_Others_Aggregate (Expr)
3543 then
3544 return False;
3546 elsif Nkind (Expr) = N_Allocator then
3548 -- For now, too complex to analyze
3550 return False;
3551 end if;
3553 Comp := New_Copy_Tree (Expr);
3554 Set_Parent (Comp, Parent (Expr));
3555 Analyze (Comp);
3556 end if;
3558 if Nkind (Comp) = N_Aggregate then
3559 return Safe_Aggregate (Comp);
3560 else
3561 return Check_Component (Comp);
3562 end if;
3563 end Safe_Component;
3565 -- Start of processing for In_Place_Assign_OK
3567 begin
3568 if Present (Component_Associations (N)) then
3570 -- On assignment, sliding can take place, so we cannot do the
3571 -- assignment in place unless the bounds of the aggregate are
3572 -- statically equal to those of the target.
3574 -- If the aggregate is given by an others choice, the bounds
3575 -- are derived from the left-hand side, and the assignment is
3576 -- safe if the expression is.
3578 if Is_Others_Aggregate (N) then
3579 return
3580 Safe_Component
3581 (Expression (First (Component_Associations (N))));
3582 end if;
3584 Aggr_In := First_Index (Etype (N));
3585 if Nkind (Parent (N)) = N_Assignment_Statement then
3586 Obj_In := First_Index (Etype (Name (Parent (N))));
3588 else
3589 -- Context is an allocator. Check bounds of aggregate
3590 -- against given type in qualified expression.
3592 pragma Assert (Nkind (Parent (Parent (N))) = N_Allocator);
3593 Obj_In :=
3594 First_Index (Etype (Entity (Subtype_Mark (Parent (N)))));
3595 end if;
3597 while Present (Aggr_In) loop
3598 Get_Index_Bounds (Aggr_In, Aggr_Lo, Aggr_Hi);
3599 Get_Index_Bounds (Obj_In, Obj_Lo, Obj_Hi);
3601 if not Compile_Time_Known_Value (Aggr_Lo)
3602 or else not Compile_Time_Known_Value (Aggr_Hi)
3603 or else not Compile_Time_Known_Value (Obj_Lo)
3604 or else not Compile_Time_Known_Value (Obj_Hi)
3605 or else Expr_Value (Aggr_Lo) /= Expr_Value (Obj_Lo)
3606 or else Expr_Value (Aggr_Hi) /= Expr_Value (Obj_Hi)
3607 then
3608 return False;
3609 end if;
3611 Next_Index (Aggr_In);
3612 Next_Index (Obj_In);
3613 end loop;
3614 end if;
3616 -- Now check the component values themselves
3618 return Safe_Aggregate (N);
3619 end In_Place_Assign_OK;
3621 ------------------
3622 -- Others_Check --
3623 ------------------
3625 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos) is
3626 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
3627 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
3628 -- The bounds of the aggregate for this dimension
3630 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
3631 -- The index type for this dimension
3633 Need_To_Check : Boolean := False;
3635 Choices_Lo : Node_Id := Empty;
3636 Choices_Hi : Node_Id := Empty;
3637 -- The lowest and highest discrete choices for a named sub-aggregate
3639 Nb_Choices : Int := -1;
3640 -- The number of discrete non-others choices in this sub-aggregate
3642 Nb_Elements : Uint := Uint_0;
3643 -- The number of elements in a positional aggregate
3645 Cond : Node_Id := Empty;
3647 Assoc : Node_Id;
3648 Choice : Node_Id;
3649 Expr : Node_Id;
3651 begin
3652 -- Check if we have an others choice. If we do make sure that this
3653 -- sub-aggregate contains at least one element in addition to the
3654 -- others choice.
3656 if Range_Checks_Suppressed (Ind_Typ) then
3657 Need_To_Check := False;
3659 elsif Present (Expressions (Sub_Aggr))
3660 and then Present (Component_Associations (Sub_Aggr))
3661 then
3662 Need_To_Check := True;
3664 elsif Present (Component_Associations (Sub_Aggr)) then
3665 Assoc := Last (Component_Associations (Sub_Aggr));
3667 if Nkind (First (Choices (Assoc))) /= N_Others_Choice then
3668 Need_To_Check := False;
3670 else
3671 -- Count the number of discrete choices. Start with -1
3672 -- because the others choice does not count.
3674 Nb_Choices := -1;
3675 Assoc := First (Component_Associations (Sub_Aggr));
3676 while Present (Assoc) loop
3677 Choice := First (Choices (Assoc));
3678 while Present (Choice) loop
3679 Nb_Choices := Nb_Choices + 1;
3680 Next (Choice);
3681 end loop;
3683 Next (Assoc);
3684 end loop;
3686 -- If there is only an others choice nothing to do
3688 Need_To_Check := (Nb_Choices > 0);
3689 end if;
3691 else
3692 Need_To_Check := False;
3693 end if;
3695 -- If we are dealing with a positional sub-aggregate with an
3696 -- others choice then compute the number or positional elements.
3698 if Need_To_Check and then Present (Expressions (Sub_Aggr)) then
3699 Expr := First (Expressions (Sub_Aggr));
3700 Nb_Elements := Uint_0;
3701 while Present (Expr) loop
3702 Nb_Elements := Nb_Elements + 1;
3703 Next (Expr);
3704 end loop;
3706 -- If the aggregate contains discrete choices and an others choice
3707 -- compute the smallest and largest discrete choice values.
3709 elsif Need_To_Check then
3710 Compute_Choices_Lo_And_Choices_Hi : declare
3712 Table : Case_Table_Type (1 .. Nb_Choices);
3713 -- Used to sort all the different choice values
3715 J : Pos := 1;
3716 Low : Node_Id;
3717 High : Node_Id;
3719 begin
3720 Assoc := First (Component_Associations (Sub_Aggr));
3721 while Present (Assoc) loop
3722 Choice := First (Choices (Assoc));
3723 while Present (Choice) loop
3724 if Nkind (Choice) = N_Others_Choice then
3725 exit;
3726 end if;
3728 Get_Index_Bounds (Choice, Low, High);
3729 Table (J).Choice_Lo := Low;
3730 Table (J).Choice_Hi := High;
3732 J := J + 1;
3733 Next (Choice);
3734 end loop;
3736 Next (Assoc);
3737 end loop;
3739 -- Sort the discrete choices
3741 Sort_Case_Table (Table);
3743 Choices_Lo := Table (1).Choice_Lo;
3744 Choices_Hi := Table (Nb_Choices).Choice_Hi;
3745 end Compute_Choices_Lo_And_Choices_Hi;
3746 end if;
3748 -- If no others choice in this sub-aggregate, or the aggregate
3749 -- comprises only an others choice, nothing to do.
3751 if not Need_To_Check then
3752 Cond := Empty;
3754 -- If we are dealing with an aggregate containing an others
3755 -- choice and positional components, we generate the following test:
3757 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
3758 -- Ind_Typ'Pos (Aggr_Hi)
3759 -- then
3760 -- raise Constraint_Error;
3761 -- end if;
3763 elsif Nb_Elements > Uint_0 then
3764 Cond :=
3765 Make_Op_Gt (Loc,
3766 Left_Opnd =>
3767 Make_Op_Add (Loc,
3768 Left_Opnd =>
3769 Make_Attribute_Reference (Loc,
3770 Prefix => New_Reference_To (Ind_Typ, Loc),
3771 Attribute_Name => Name_Pos,
3772 Expressions =>
3773 New_List
3774 (Duplicate_Subexpr_Move_Checks (Aggr_Lo))),
3775 Right_Opnd => Make_Integer_Literal (Loc, Nb_Elements - 1)),
3777 Right_Opnd =>
3778 Make_Attribute_Reference (Loc,
3779 Prefix => New_Reference_To (Ind_Typ, Loc),
3780 Attribute_Name => Name_Pos,
3781 Expressions => New_List (
3782 Duplicate_Subexpr_Move_Checks (Aggr_Hi))));
3784 -- If we are dealing with an aggregate containing an others
3785 -- choice and discrete choices we generate the following test:
3787 -- [constraint_error when
3788 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
3790 else
3791 Cond :=
3792 Make_Or_Else (Loc,
3793 Left_Opnd =>
3794 Make_Op_Lt (Loc,
3795 Left_Opnd =>
3796 Duplicate_Subexpr_Move_Checks (Choices_Lo),
3797 Right_Opnd =>
3798 Duplicate_Subexpr_Move_Checks (Aggr_Lo)),
3800 Right_Opnd =>
3801 Make_Op_Gt (Loc,
3802 Left_Opnd =>
3803 Duplicate_Subexpr (Choices_Hi),
3804 Right_Opnd =>
3805 Duplicate_Subexpr (Aggr_Hi)));
3806 end if;
3808 if Present (Cond) then
3809 Insert_Action (N,
3810 Make_Raise_Constraint_Error (Loc,
3811 Condition => Cond,
3812 Reason => CE_Length_Check_Failed));
3813 end if;
3815 -- Now look inside the sub-aggregate to see if there is more work
3817 if Dim < Aggr_Dimension then
3819 -- Process positional components
3821 if Present (Expressions (Sub_Aggr)) then
3822 Expr := First (Expressions (Sub_Aggr));
3823 while Present (Expr) loop
3824 Others_Check (Expr, Dim + 1);
3825 Next (Expr);
3826 end loop;
3827 end if;
3829 -- Process component associations
3831 if Present (Component_Associations (Sub_Aggr)) then
3832 Assoc := First (Component_Associations (Sub_Aggr));
3833 while Present (Assoc) loop
3834 Expr := Expression (Assoc);
3835 Others_Check (Expr, Dim + 1);
3836 Next (Assoc);
3837 end loop;
3838 end if;
3839 end if;
3840 end Others_Check;
3842 -- Remaining Expand_Array_Aggregate variables
3844 Tmp : Entity_Id;
3845 -- Holds the temporary aggregate value
3847 Tmp_Decl : Node_Id;
3848 -- Holds the declaration of Tmp
3850 Aggr_Code : List_Id;
3851 Parent_Node : Node_Id;
3852 Parent_Kind : Node_Kind;
3854 -- Start of processing for Expand_Array_Aggregate
3856 begin
3857 -- Do not touch the special aggregates of attributes used for Asm calls
3859 if Is_RTE (Ctyp, RE_Asm_Input_Operand)
3860 or else Is_RTE (Ctyp, RE_Asm_Output_Operand)
3861 then
3862 return;
3863 end if;
3865 -- If the semantic analyzer has determined that aggregate N will raise
3866 -- Constraint_Error at run-time, then the aggregate node has been
3867 -- replaced with an N_Raise_Constraint_Error node and we should
3868 -- never get here.
3870 pragma Assert (not Raises_Constraint_Error (N));
3872 -- STEP 1a
3874 -- Check that the index range defined by aggregate bounds is
3875 -- compatible with corresponding index subtype.
3877 Index_Compatibility_Check : declare
3878 Aggr_Index_Range : Node_Id := First_Index (Typ);
3879 -- The current aggregate index range
3881 Index_Constraint : Node_Id := First_Index (Etype (Typ));
3882 -- The corresponding index constraint against which we have to
3883 -- check the above aggregate index range.
3885 begin
3886 Compute_Others_Present (N, 1);
3888 for J in 1 .. Aggr_Dimension loop
3889 -- There is no need to emit a check if an others choice is
3890 -- present for this array aggregate dimension since in this
3891 -- case one of N's sub-aggregates has taken its bounds from the
3892 -- context and these bounds must have been checked already. In
3893 -- addition all sub-aggregates corresponding to the same
3894 -- dimension must all have the same bounds (checked in (c) below).
3896 if not Range_Checks_Suppressed (Etype (Index_Constraint))
3897 and then not Others_Present (J)
3898 then
3899 -- We don't use Checks.Apply_Range_Check here because it
3900 -- emits a spurious check. Namely it checks that the range
3901 -- defined by the aggregate bounds is non empty. But we know
3902 -- this already if we get here.
3904 Check_Bounds (Aggr_Index_Range, Index_Constraint);
3905 end if;
3907 -- Save the low and high bounds of the aggregate index as well
3908 -- as the index type for later use in checks (b) and (c) below.
3910 Aggr_Low (J) := Low_Bound (Aggr_Index_Range);
3911 Aggr_High (J) := High_Bound (Aggr_Index_Range);
3913 Aggr_Index_Typ (J) := Etype (Index_Constraint);
3915 Next_Index (Aggr_Index_Range);
3916 Next_Index (Index_Constraint);
3917 end loop;
3918 end Index_Compatibility_Check;
3920 -- STEP 1b
3922 -- If an others choice is present check that no aggregate
3923 -- index is outside the bounds of the index constraint.
3925 Others_Check (N, 1);
3927 -- STEP 1c
3929 -- For multidimensional arrays make sure that all subaggregates
3930 -- corresponding to the same dimension have the same bounds.
3932 if Aggr_Dimension > 1 then
3933 Check_Same_Aggr_Bounds (N, 1);
3934 end if;
3936 -- STEP 2
3938 -- Here we test for is packed array aggregate that we can handle
3939 -- at compile time. If so, return with transformation done. Note
3940 -- that we do this even if the aggregate is nested, because once
3941 -- we have done this processing, there is no more nested aggregate!
3943 if Packed_Array_Aggregate_Handled (N) then
3944 return;
3945 end if;
3947 -- At this point we try to convert to positional form
3949 Convert_To_Positional (N);
3951 -- if the result is no longer an aggregate (e.g. it may be a string
3952 -- literal, or a temporary which has the needed value), then we are
3953 -- done, since there is no longer a nested aggregate.
3955 if Nkind (N) /= N_Aggregate then
3956 return;
3958 -- We are also done if the result is an analyzed aggregate
3959 -- This case could use more comments ???
3961 elsif Analyzed (N)
3962 and then N /= Original_Node (N)
3963 then
3964 return;
3965 end if;
3967 -- Now see if back end processing is possible
3969 if Backend_Processing_Possible (N) then
3971 -- If the aggregate is static but the constraints are not, build
3972 -- a static subtype for the aggregate, so that Gigi can place it
3973 -- in static memory. Perform an unchecked_conversion to the non-
3974 -- static type imposed by the context.
3976 declare
3977 Itype : constant Entity_Id := Etype (N);
3978 Index : Node_Id;
3979 Needs_Type : Boolean := False;
3981 begin
3982 Index := First_Index (Itype);
3984 while Present (Index) loop
3985 if not Is_Static_Subtype (Etype (Index)) then
3986 Needs_Type := True;
3987 exit;
3988 else
3989 Next_Index (Index);
3990 end if;
3991 end loop;
3993 if Needs_Type then
3994 Build_Constrained_Type (Positional => True);
3995 Rewrite (N, Unchecked_Convert_To (Itype, N));
3996 Analyze (N);
3997 end if;
3998 end;
4000 return;
4001 end if;
4003 -- STEP 3
4005 -- Delay expansion for nested aggregates it will be taken care of
4006 -- when the parent aggregate is expanded
4008 Parent_Node := Parent (N);
4009 Parent_Kind := Nkind (Parent_Node);
4011 if Parent_Kind = N_Qualified_Expression then
4012 Parent_Node := Parent (Parent_Node);
4013 Parent_Kind := Nkind (Parent_Node);
4014 end if;
4016 if Parent_Kind = N_Aggregate
4017 or else Parent_Kind = N_Extension_Aggregate
4018 or else Parent_Kind = N_Component_Association
4019 or else (Parent_Kind = N_Object_Declaration
4020 and then Controlled_Type (Typ))
4021 or else (Parent_Kind = N_Assignment_Statement
4022 and then Inside_Init_Proc)
4023 then
4024 Set_Expansion_Delayed (N);
4025 return;
4026 end if;
4028 -- STEP 4
4030 -- Look if in place aggregate expansion is possible
4032 -- For object declarations we build the aggregate in place, unless
4033 -- the array is bit-packed or the component is controlled.
4035 -- For assignments we do the assignment in place if all the component
4036 -- associations have compile-time known values. For other cases we
4037 -- create a temporary. The analysis for safety of on-line assignment
4038 -- is delicate, i.e. we don't know how to do it fully yet ???
4040 -- For allocators we assign to the designated object in place if the
4041 -- aggregate meets the same conditions as other in-place assignments.
4042 -- In this case the aggregate may not come from source but was created
4043 -- for default initialization, e.g. with Initialize_Scalars.
4045 if Requires_Transient_Scope (Typ) then
4046 Establish_Transient_Scope
4047 (N, Sec_Stack => Has_Controlled_Component (Typ));
4048 end if;
4050 if Has_Default_Init_Comps (N) then
4051 Maybe_In_Place_OK := False;
4053 elsif Is_Bit_Packed_Array (Typ)
4054 or else Has_Controlled_Component (Typ)
4055 then
4056 Maybe_In_Place_OK := False;
4058 else
4059 Maybe_In_Place_OK :=
4060 (Nkind (Parent (N)) = N_Assignment_Statement
4061 and then Comes_From_Source (N)
4062 and then In_Place_Assign_OK)
4064 or else
4065 (Nkind (Parent (Parent (N))) = N_Allocator
4066 and then In_Place_Assign_OK);
4067 end if;
4069 if not Has_Default_Init_Comps (N)
4070 and then Comes_From_Source (Parent (N))
4071 and then Nkind (Parent (N)) = N_Object_Declaration
4072 and then not
4073 Must_Slide (Etype (Defining_Identifier (Parent (N))), Typ)
4074 and then N = Expression (Parent (N))
4075 and then not Is_Bit_Packed_Array (Typ)
4076 and then not Has_Controlled_Component (Typ)
4077 and then not Has_Address_Clause (Parent (N))
4078 then
4079 Tmp := Defining_Identifier (Parent (N));
4080 Set_No_Initialization (Parent (N));
4081 Set_Expression (Parent (N), Empty);
4083 -- Set the type of the entity, for use in the analysis of the
4084 -- subsequent indexed assignments. If the nominal type is not
4085 -- constrained, build a subtype from the known bounds of the
4086 -- aggregate. If the declaration has a subtype mark, use it,
4087 -- otherwise use the itype of the aggregate.
4089 if not Is_Constrained (Typ) then
4090 Build_Constrained_Type (Positional => False);
4091 elsif Is_Entity_Name (Object_Definition (Parent (N)))
4092 and then Is_Constrained (Entity (Object_Definition (Parent (N))))
4093 then
4094 Set_Etype (Tmp, Entity (Object_Definition (Parent (N))));
4095 else
4096 Set_Size_Known_At_Compile_Time (Typ, False);
4097 Set_Etype (Tmp, Typ);
4098 end if;
4100 elsif Maybe_In_Place_OK
4101 and then Nkind (Parent (N)) = N_Qualified_Expression
4102 and then Nkind (Parent (Parent (N))) = N_Allocator
4103 then
4104 Set_Expansion_Delayed (N);
4105 return;
4107 -- In the remaining cases the aggregate is the RHS of an assignment
4109 elsif Maybe_In_Place_OK
4110 and then Is_Entity_Name (Name (Parent (N)))
4111 then
4112 Tmp := Entity (Name (Parent (N)));
4114 if Etype (Tmp) /= Etype (N) then
4115 Apply_Length_Check (N, Etype (Tmp));
4117 if Nkind (N) = N_Raise_Constraint_Error then
4119 -- Static error, nothing further to expand
4121 return;
4122 end if;
4123 end if;
4125 elsif Maybe_In_Place_OK
4126 and then Nkind (Name (Parent (N))) = N_Explicit_Dereference
4127 and then Is_Entity_Name (Prefix (Name (Parent (N))))
4128 then
4129 Tmp := Name (Parent (N));
4131 if Etype (Tmp) /= Etype (N) then
4132 Apply_Length_Check (N, Etype (Tmp));
4133 end if;
4135 elsif Maybe_In_Place_OK
4136 and then Nkind (Name (Parent (N))) = N_Slice
4137 and then Safe_Slice_Assignment (N)
4138 then
4139 -- Safe_Slice_Assignment rewrites assignment as a loop
4141 return;
4143 -- Step 5
4145 -- In place aggregate expansion is not possible
4147 else
4148 Maybe_In_Place_OK := False;
4149 Tmp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4150 Tmp_Decl :=
4151 Make_Object_Declaration
4152 (Loc,
4153 Defining_Identifier => Tmp,
4154 Object_Definition => New_Occurrence_Of (Typ, Loc));
4155 Set_No_Initialization (Tmp_Decl, True);
4157 -- If we are within a loop, the temporary will be pushed on the
4158 -- stack at each iteration. If the aggregate is the expression for
4159 -- an allocator, it will be immediately copied to the heap and can
4160 -- be reclaimed at once. We create a transient scope around the
4161 -- aggregate for this purpose.
4163 if Ekind (Current_Scope) = E_Loop
4164 and then Nkind (Parent (Parent (N))) = N_Allocator
4165 then
4166 Establish_Transient_Scope (N, False);
4167 end if;
4169 Insert_Action (N, Tmp_Decl);
4170 end if;
4172 -- Construct and insert the aggregate code. We can safely suppress
4173 -- index checks because this code is guaranteed not to raise CE
4174 -- on index checks. However we should *not* suppress all checks.
4176 declare
4177 Target : Node_Id;
4179 begin
4180 if Nkind (Tmp) = N_Defining_Identifier then
4181 Target := New_Reference_To (Tmp, Loc);
4183 else
4185 if Has_Default_Init_Comps (N) then
4187 -- Ada 2005 (AI-287): This case has not been analyzed???
4189 raise Program_Error;
4190 end if;
4192 -- Name in assignment is explicit dereference
4194 Target := New_Copy (Tmp);
4195 end if;
4197 Aggr_Code :=
4198 Build_Array_Aggr_Code (N,
4199 Ctype => Ctyp,
4200 Index => First_Index (Typ),
4201 Into => Target,
4202 Scalar_Comp => Is_Scalar_Type (Ctyp));
4203 end;
4205 if Comes_From_Source (Tmp) then
4206 Insert_Actions_After (Parent (N), Aggr_Code);
4208 else
4209 Insert_Actions (N, Aggr_Code);
4210 end if;
4212 -- If the aggregate has been assigned in place, remove the original
4213 -- assignment.
4215 if Nkind (Parent (N)) = N_Assignment_Statement
4216 and then Maybe_In_Place_OK
4217 then
4218 Rewrite (Parent (N), Make_Null_Statement (Loc));
4220 elsif Nkind (Parent (N)) /= N_Object_Declaration
4221 or else Tmp /= Defining_Identifier (Parent (N))
4222 then
4223 Rewrite (N, New_Occurrence_Of (Tmp, Loc));
4224 Analyze_And_Resolve (N, Typ);
4225 end if;
4226 end Expand_Array_Aggregate;
4228 ------------------------
4229 -- Expand_N_Aggregate --
4230 ------------------------
4232 procedure Expand_N_Aggregate (N : Node_Id) is
4233 begin
4234 if Is_Record_Type (Etype (N)) then
4235 Expand_Record_Aggregate (N);
4236 else
4237 Expand_Array_Aggregate (N);
4238 end if;
4240 exception
4241 when RE_Not_Available =>
4242 return;
4243 end Expand_N_Aggregate;
4245 ----------------------------------
4246 -- Expand_N_Extension_Aggregate --
4247 ----------------------------------
4249 -- If the ancestor part is an expression, add a component association for
4250 -- the parent field. If the type of the ancestor part is not the direct
4251 -- parent of the expected type, build recursively the needed ancestors.
4252 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
4253 -- ration for a temporary of the expected type, followed by individual
4254 -- assignments to the given components.
4256 procedure Expand_N_Extension_Aggregate (N : Node_Id) is
4257 Loc : constant Source_Ptr := Sloc (N);
4258 A : constant Node_Id := Ancestor_Part (N);
4259 Typ : constant Entity_Id := Etype (N);
4261 begin
4262 -- If the ancestor is a subtype mark, an init proc must be called
4263 -- on the resulting object which thus has to be materialized in
4264 -- the front-end
4266 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
4267 Convert_To_Assignments (N, Typ);
4269 -- The extension aggregate is transformed into a record aggregate
4270 -- of the following form (c1 and c2 are inherited components)
4272 -- (Exp with c3 => a, c4 => b)
4273 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c1 => a, c2 => b)
4275 else
4276 Set_Etype (N, Typ);
4278 -- No tag is needed in the case of Java_VM
4280 if Java_VM then
4281 Expand_Record_Aggregate (N,
4282 Parent_Expr => A);
4283 else
4284 Expand_Record_Aggregate (N,
4285 Orig_Tag => New_Occurrence_Of (Access_Disp_Table (Typ), Loc),
4286 Parent_Expr => A);
4287 end if;
4288 end if;
4290 exception
4291 when RE_Not_Available =>
4292 return;
4293 end Expand_N_Extension_Aggregate;
4295 -----------------------------
4296 -- Expand_Record_Aggregate --
4297 -----------------------------
4299 procedure Expand_Record_Aggregate
4300 (N : Node_Id;
4301 Orig_Tag : Node_Id := Empty;
4302 Parent_Expr : Node_Id := Empty)
4304 Loc : constant Source_Ptr := Sloc (N);
4305 Comps : constant List_Id := Component_Associations (N);
4306 Typ : constant Entity_Id := Etype (N);
4307 Base_Typ : constant Entity_Id := Base_Type (Typ);
4309 function Has_Delayed_Nested_Aggregate_Or_Tagged_Comps return Boolean;
4310 -- Checks the presence of a nested aggregate which needs Late_Expansion
4311 -- or the presence of tagged components which may need tag adjustment.
4313 --------------------------------------------------
4314 -- Has_Delayed_Nested_Aggregate_Or_Tagged_Comps --
4315 --------------------------------------------------
4317 function Has_Delayed_Nested_Aggregate_Or_Tagged_Comps return Boolean is
4318 C : Node_Id;
4319 Expr_Q : Node_Id;
4321 begin
4322 if No (Comps) then
4323 return False;
4324 end if;
4326 C := First (Comps);
4327 while Present (C) loop
4328 if Nkind (Expression (C)) = N_Qualified_Expression then
4329 Expr_Q := Expression (Expression (C));
4330 else
4331 Expr_Q := Expression (C);
4332 end if;
4334 -- Return true if the aggregate has any associations for
4335 -- tagged components that may require tag adjustment.
4336 -- These are cases where the source expression may have
4337 -- a tag that could differ from the component tag (e.g.,
4338 -- can occur for type conversions and formal parameters).
4339 -- (Tag adjustment is not needed if Java_VM because object
4340 -- tags are implicit in the JVM.)
4342 if Is_Tagged_Type (Etype (Expr_Q))
4343 and then (Nkind (Expr_Q) = N_Type_Conversion
4344 or else (Is_Entity_Name (Expr_Q)
4345 and then Ekind (Entity (Expr_Q)) in Formal_Kind))
4346 and then not Java_VM
4347 then
4348 return True;
4349 end if;
4351 if Is_Delayed_Aggregate (Expr_Q) then
4352 return True;
4353 end if;
4355 Next (C);
4356 end loop;
4358 return False;
4359 end Has_Delayed_Nested_Aggregate_Or_Tagged_Comps;
4361 -- Remaining Expand_Record_Aggregate variables
4363 Tag_Value : Node_Id;
4364 Comp : Entity_Id;
4365 New_Comp : Node_Id;
4367 -- Start of processing for Expand_Record_Aggregate
4369 begin
4370 -- If the aggregate is to be assigned to an atomic variable, we
4371 -- have to prevent a piecemeal assignment even if the aggregate
4372 -- is to be expanded. We create a temporary for the aggregate, and
4373 -- assign the temporary instead, so that the back end can generate
4374 -- an atomic move for it.
4376 if Is_Atomic (Typ)
4377 and then (Nkind (Parent (N)) = N_Object_Declaration
4378 or else Nkind (Parent (N)) = N_Assignment_Statement)
4379 and then Comes_From_Source (Parent (N))
4380 then
4381 Expand_Atomic_Aggregate (N, Typ);
4382 return;
4383 end if;
4385 -- Gigi doesn't handle properly temporaries of variable size
4386 -- so we generate it in the front-end
4388 if not Size_Known_At_Compile_Time (Typ) then
4389 Convert_To_Assignments (N, Typ);
4391 -- Temporaries for controlled aggregates need to be attached to a
4392 -- final chain in order to be properly finalized, so it has to
4393 -- be created in the front-end
4395 elsif Is_Controlled (Typ)
4396 or else Has_Controlled_Component (Base_Type (Typ))
4397 then
4398 Convert_To_Assignments (N, Typ);
4400 -- Ada 2005 (AI-287): In case of default initialized components we
4401 -- convert the aggregate into assignments.
4403 elsif Has_Default_Init_Comps (N) then
4404 Convert_To_Assignments (N, Typ);
4406 elsif Has_Delayed_Nested_Aggregate_Or_Tagged_Comps then
4407 Convert_To_Assignments (N, Typ);
4409 -- If an ancestor is private, some components are not inherited and
4410 -- we cannot expand into a record aggregate
4412 elsif Has_Private_Ancestor (Typ) then
4413 Convert_To_Assignments (N, Typ);
4415 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
4416 -- is not able to handle the aggregate for Late_Request.
4418 elsif Is_Tagged_Type (Typ) and then Has_Discriminants (Typ) then
4419 Convert_To_Assignments (N, Typ);
4421 -- If some components are mutable, the size of the aggregate component
4422 -- may be disctinct from the default size of the type component, so
4423 -- we need to expand to insure that the back-end copies the proper
4424 -- size of the data.
4426 elsif Has_Mutable_Components (Typ) then
4427 Convert_To_Assignments (N, Typ);
4429 -- If the type involved has any non-bit aligned components, then
4430 -- we are not sure that the back end can handle this case correctly.
4432 elsif Type_May_Have_Bit_Aligned_Components (Typ) then
4433 Convert_To_Assignments (N, Typ);
4435 -- In all other cases we generate a proper aggregate that
4436 -- can be handled by gigi.
4438 else
4439 -- If no discriminants, nothing special to do
4441 if not Has_Discriminants (Typ) then
4442 null;
4444 -- Case of discriminants present
4446 elsif Is_Derived_Type (Typ) then
4448 -- For untagged types, non-stored discriminants are replaced
4449 -- with stored discriminants, which are the ones that gigi uses
4450 -- to describe the type and its components.
4452 Generate_Aggregate_For_Derived_Type : declare
4453 Constraints : constant List_Id := New_List;
4454 First_Comp : Node_Id;
4455 Discriminant : Entity_Id;
4456 Decl : Node_Id;
4457 Num_Disc : Int := 0;
4458 Num_Gird : Int := 0;
4460 procedure Prepend_Stored_Values (T : Entity_Id);
4461 -- Scan the list of stored discriminants of the type, and
4462 -- add their values to the aggregate being built.
4464 ---------------------------
4465 -- Prepend_Stored_Values --
4466 ---------------------------
4468 procedure Prepend_Stored_Values (T : Entity_Id) is
4469 begin
4470 Discriminant := First_Stored_Discriminant (T);
4472 while Present (Discriminant) loop
4473 New_Comp :=
4474 Make_Component_Association (Loc,
4475 Choices =>
4476 New_List (New_Occurrence_Of (Discriminant, Loc)),
4478 Expression =>
4479 New_Copy_Tree (
4480 Get_Discriminant_Value (
4481 Discriminant,
4482 Typ,
4483 Discriminant_Constraint (Typ))));
4485 if No (First_Comp) then
4486 Prepend_To (Component_Associations (N), New_Comp);
4487 else
4488 Insert_After (First_Comp, New_Comp);
4489 end if;
4491 First_Comp := New_Comp;
4492 Next_Stored_Discriminant (Discriminant);
4493 end loop;
4494 end Prepend_Stored_Values;
4496 -- Start of processing for Generate_Aggregate_For_Derived_Type
4498 begin
4499 -- Remove the associations for the discriminant of
4500 -- the derived type.
4502 First_Comp := First (Component_Associations (N));
4504 while Present (First_Comp) loop
4505 Comp := First_Comp;
4506 Next (First_Comp);
4508 if Ekind (Entity (First (Choices (Comp)))) =
4509 E_Discriminant
4510 then
4511 Remove (Comp);
4512 Num_Disc := Num_Disc + 1;
4513 end if;
4514 end loop;
4516 -- Insert stored discriminant associations in the correct
4517 -- order. If there are more stored discriminants than new
4518 -- discriminants, there is at least one new discriminant
4519 -- that constrains more than one of the stored discriminants.
4520 -- In this case we need to construct a proper subtype of
4521 -- the parent type, in order to supply values to all the
4522 -- components. Otherwise there is one-one correspondence
4523 -- between the constraints and the stored discriminants.
4525 First_Comp := Empty;
4527 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
4529 while Present (Discriminant) loop
4530 Num_Gird := Num_Gird + 1;
4531 Next_Stored_Discriminant (Discriminant);
4532 end loop;
4534 -- Case of more stored discriminants than new discriminants
4536 if Num_Gird > Num_Disc then
4538 -- Create a proper subtype of the parent type, which is
4539 -- the proper implementation type for the aggregate, and
4540 -- convert it to the intended target type.
4542 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
4544 while Present (Discriminant) loop
4545 New_Comp :=
4546 New_Copy_Tree (
4547 Get_Discriminant_Value (
4548 Discriminant,
4549 Typ,
4550 Discriminant_Constraint (Typ)));
4551 Append (New_Comp, Constraints);
4552 Next_Stored_Discriminant (Discriminant);
4553 end loop;
4555 Decl :=
4556 Make_Subtype_Declaration (Loc,
4557 Defining_Identifier =>
4558 Make_Defining_Identifier (Loc,
4559 New_Internal_Name ('T')),
4560 Subtype_Indication =>
4561 Make_Subtype_Indication (Loc,
4562 Subtype_Mark =>
4563 New_Occurrence_Of (Etype (Base_Type (Typ)), Loc),
4564 Constraint =>
4565 Make_Index_Or_Discriminant_Constraint
4566 (Loc, Constraints)));
4568 Insert_Action (N, Decl);
4569 Prepend_Stored_Values (Base_Type (Typ));
4571 Set_Etype (N, Defining_Identifier (Decl));
4572 Set_Analyzed (N);
4574 Rewrite (N, Unchecked_Convert_To (Typ, N));
4575 Analyze (N);
4577 -- Case where we do not have fewer new discriminants than
4578 -- stored discriminants, so in this case we can simply
4579 -- use the stored discriminants of the subtype.
4581 else
4582 Prepend_Stored_Values (Typ);
4583 end if;
4584 end Generate_Aggregate_For_Derived_Type;
4585 end if;
4587 if Is_Tagged_Type (Typ) then
4589 -- The tagged case, _parent and _tag component must be created
4591 -- Reset null_present unconditionally. tagged records always have
4592 -- at least one field (the tag or the parent)
4594 Set_Null_Record_Present (N, False);
4596 -- When the current aggregate comes from the expansion of an
4597 -- extension aggregate, the parent expr is replaced by an
4598 -- aggregate formed by selected components of this expr
4600 if Present (Parent_Expr)
4601 and then Is_Empty_List (Comps)
4602 then
4603 Comp := First_Entity (Typ);
4604 while Present (Comp) loop
4606 -- Skip all entities that aren't discriminants or components
4608 if Ekind (Comp) /= E_Discriminant
4609 and then Ekind (Comp) /= E_Component
4610 then
4611 null;
4613 -- Skip all expander-generated components
4615 elsif
4616 not Comes_From_Source (Original_Record_Component (Comp))
4617 then
4618 null;
4620 else
4621 New_Comp :=
4622 Make_Selected_Component (Loc,
4623 Prefix =>
4624 Unchecked_Convert_To (Typ,
4625 Duplicate_Subexpr (Parent_Expr, True)),
4627 Selector_Name => New_Occurrence_Of (Comp, Loc));
4629 Append_To (Comps,
4630 Make_Component_Association (Loc,
4631 Choices =>
4632 New_List (New_Occurrence_Of (Comp, Loc)),
4633 Expression =>
4634 New_Comp));
4636 Analyze_And_Resolve (New_Comp, Etype (Comp));
4637 end if;
4639 Next_Entity (Comp);
4640 end loop;
4641 end if;
4643 -- Compute the value for the Tag now, if the type is a root it
4644 -- will be included in the aggregate right away, otherwise it will
4645 -- be propagated to the parent aggregate
4647 if Present (Orig_Tag) then
4648 Tag_Value := Orig_Tag;
4649 elsif Java_VM then
4650 Tag_Value := Empty;
4651 else
4652 Tag_Value := New_Occurrence_Of (Access_Disp_Table (Typ), Loc);
4653 end if;
4655 -- For a derived type, an aggregate for the parent is formed with
4656 -- all the inherited components.
4658 if Is_Derived_Type (Typ) then
4660 declare
4661 First_Comp : Node_Id;
4662 Parent_Comps : List_Id;
4663 Parent_Aggr : Node_Id;
4664 Parent_Name : Node_Id;
4666 begin
4667 -- Remove the inherited component association from the
4668 -- aggregate and store them in the parent aggregate
4670 First_Comp := First (Component_Associations (N));
4671 Parent_Comps := New_List;
4673 while Present (First_Comp)
4674 and then Scope (Original_Record_Component (
4675 Entity (First (Choices (First_Comp))))) /= Base_Typ
4676 loop
4677 Comp := First_Comp;
4678 Next (First_Comp);
4679 Remove (Comp);
4680 Append (Comp, Parent_Comps);
4681 end loop;
4683 Parent_Aggr := Make_Aggregate (Loc,
4684 Component_Associations => Parent_Comps);
4685 Set_Etype (Parent_Aggr, Etype (Base_Type (Typ)));
4687 -- Find the _parent component
4689 Comp := First_Component (Typ);
4690 while Chars (Comp) /= Name_uParent loop
4691 Comp := Next_Component (Comp);
4692 end loop;
4694 Parent_Name := New_Occurrence_Of (Comp, Loc);
4696 -- Insert the parent aggregate
4698 Prepend_To (Component_Associations (N),
4699 Make_Component_Association (Loc,
4700 Choices => New_List (Parent_Name),
4701 Expression => Parent_Aggr));
4703 -- Expand recursively the parent propagating the right Tag
4705 Expand_Record_Aggregate (
4706 Parent_Aggr, Tag_Value, Parent_Expr);
4707 end;
4709 -- For a root type, the tag component is added (unless compiling
4710 -- for the Java VM, where tags are implicit).
4712 elsif not Java_VM then
4713 declare
4714 Tag_Name : constant Node_Id :=
4715 New_Occurrence_Of (Tag_Component (Typ), Loc);
4716 Typ_Tag : constant Entity_Id := RTE (RE_Tag);
4717 Conv_Node : constant Node_Id :=
4718 Unchecked_Convert_To (Typ_Tag, Tag_Value);
4720 begin
4721 Set_Etype (Conv_Node, Typ_Tag);
4722 Prepend_To (Component_Associations (N),
4723 Make_Component_Association (Loc,
4724 Choices => New_List (Tag_Name),
4725 Expression => Conv_Node));
4726 end;
4727 end if;
4728 end if;
4729 end if;
4730 end Expand_Record_Aggregate;
4732 ----------------------------
4733 -- Has_Default_Init_Comps --
4734 ----------------------------
4736 function Has_Default_Init_Comps (N : Node_Id) return Boolean is
4737 Comps : constant List_Id := Component_Associations (N);
4738 C : Node_Id;
4739 Expr : Node_Id;
4740 begin
4741 pragma Assert (Nkind (N) = N_Aggregate
4742 or else Nkind (N) = N_Extension_Aggregate);
4744 if No (Comps) then
4745 return False;
4746 end if;
4748 -- Check if any direct component has default initialized components
4750 C := First (Comps);
4751 while Present (C) loop
4752 if Box_Present (C) then
4753 return True;
4754 end if;
4756 Next (C);
4757 end loop;
4759 -- Recursive call in case of aggregate expression
4761 C := First (Comps);
4762 while Present (C) loop
4763 Expr := Expression (C);
4765 if Present (Expr)
4766 and then (Nkind (Expr) = N_Aggregate
4767 or else Nkind (Expr) = N_Extension_Aggregate)
4768 and then Has_Default_Init_Comps (Expr)
4769 then
4770 return True;
4771 end if;
4773 Next (C);
4774 end loop;
4776 return False;
4777 end Has_Default_Init_Comps;
4779 --------------------------
4780 -- Is_Delayed_Aggregate --
4781 --------------------------
4783 function Is_Delayed_Aggregate (N : Node_Id) return Boolean is
4784 Node : Node_Id := N;
4785 Kind : Node_Kind := Nkind (Node);
4787 begin
4788 if Kind = N_Qualified_Expression then
4789 Node := Expression (Node);
4790 Kind := Nkind (Node);
4791 end if;
4793 if Kind /= N_Aggregate and then Kind /= N_Extension_Aggregate then
4794 return False;
4795 else
4796 return Expansion_Delayed (Node);
4797 end if;
4798 end Is_Delayed_Aggregate;
4800 --------------------
4801 -- Late_Expansion --
4802 --------------------
4804 function Late_Expansion
4805 (N : Node_Id;
4806 Typ : Entity_Id;
4807 Target : Node_Id;
4808 Flist : Node_Id := Empty;
4809 Obj : Entity_Id := Empty) return List_Id
4811 begin
4812 if Is_Record_Type (Etype (N)) then
4813 return Build_Record_Aggr_Code (N, Typ, Target, Flist, Obj);
4815 else pragma Assert (Is_Array_Type (Etype (N)));
4816 return
4817 Build_Array_Aggr_Code
4818 (N => N,
4819 Ctype => Component_Type (Etype (N)),
4820 Index => First_Index (Typ),
4821 Into => Target,
4822 Scalar_Comp => Is_Scalar_Type (Component_Type (Typ)),
4823 Indices => No_List,
4824 Flist => Flist);
4825 end if;
4826 end Late_Expansion;
4828 ----------------------------------
4829 -- Make_OK_Assignment_Statement --
4830 ----------------------------------
4832 function Make_OK_Assignment_Statement
4833 (Sloc : Source_Ptr;
4834 Name : Node_Id;
4835 Expression : Node_Id) return Node_Id
4837 begin
4838 Set_Assignment_OK (Name);
4839 return Make_Assignment_Statement (Sloc, Name, Expression);
4840 end Make_OK_Assignment_Statement;
4842 -----------------------
4843 -- Number_Of_Choices --
4844 -----------------------
4846 function Number_Of_Choices (N : Node_Id) return Nat is
4847 Assoc : Node_Id;
4848 Choice : Node_Id;
4850 Nb_Choices : Nat := 0;
4852 begin
4853 if Present (Expressions (N)) then
4854 return 0;
4855 end if;
4857 Assoc := First (Component_Associations (N));
4858 while Present (Assoc) loop
4860 Choice := First (Choices (Assoc));
4861 while Present (Choice) loop
4863 if Nkind (Choice) /= N_Others_Choice then
4864 Nb_Choices := Nb_Choices + 1;
4865 end if;
4867 Next (Choice);
4868 end loop;
4870 Next (Assoc);
4871 end loop;
4873 return Nb_Choices;
4874 end Number_Of_Choices;
4876 ------------------------------------
4877 -- Packed_Array_Aggregate_Handled --
4878 ------------------------------------
4880 -- The current version of this procedure will handle at compile time
4881 -- any array aggregate that meets these conditions:
4883 -- One dimensional, bit packed
4884 -- Underlying packed type is modular type
4885 -- Bounds are within 32-bit Int range
4886 -- All bounds and values are static
4888 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean is
4889 Loc : constant Source_Ptr := Sloc (N);
4890 Typ : constant Entity_Id := Etype (N);
4891 Ctyp : constant Entity_Id := Component_Type (Typ);
4893 Not_Handled : exception;
4894 -- Exception raised if this aggregate cannot be handled
4896 begin
4897 -- For now, handle only one dimensional bit packed arrays
4899 if not Is_Bit_Packed_Array (Typ)
4900 or else Number_Dimensions (Typ) > 1
4901 or else not Is_Modular_Integer_Type (Packed_Array_Type (Typ))
4902 then
4903 return False;
4904 end if;
4906 declare
4907 Csiz : constant Nat := UI_To_Int (Component_Size (Typ));
4909 Lo : Node_Id;
4910 Hi : Node_Id;
4911 -- Bounds of index type
4913 Lob : Uint;
4914 Hib : Uint;
4915 -- Values of bounds if compile time known
4917 function Get_Component_Val (N : Node_Id) return Uint;
4918 -- Given a expression value N of the component type Ctyp, returns
4919 -- A value of Csiz (component size) bits representing this value.
4920 -- If the value is non-static or any other reason exists why the
4921 -- value cannot be returned, then Not_Handled is raised.
4923 -----------------------
4924 -- Get_Component_Val --
4925 -----------------------
4927 function Get_Component_Val (N : Node_Id) return Uint is
4928 Val : Uint;
4930 begin
4931 -- We have to analyze the expression here before doing any further
4932 -- processing here. The analysis of such expressions is deferred
4933 -- till expansion to prevent some problems of premature analysis.
4935 Analyze_And_Resolve (N, Ctyp);
4937 -- Must have a compile time value. String literals have to
4938 -- be converted into temporaries as well, because they cannot
4939 -- easily be converted into their bit representation.
4941 if not Compile_Time_Known_Value (N)
4942 or else Nkind (N) = N_String_Literal
4943 then
4944 raise Not_Handled;
4945 end if;
4947 Val := Expr_Rep_Value (N);
4949 -- Adjust for bias, and strip proper number of bits
4951 if Has_Biased_Representation (Ctyp) then
4952 Val := Val - Expr_Value (Type_Low_Bound (Ctyp));
4953 end if;
4955 return Val mod Uint_2 ** Csiz;
4956 end Get_Component_Val;
4958 -- Here we know we have a one dimensional bit packed array
4960 begin
4961 Get_Index_Bounds (First_Index (Typ), Lo, Hi);
4963 -- Cannot do anything if bounds are dynamic
4965 if not Compile_Time_Known_Value (Lo)
4966 or else
4967 not Compile_Time_Known_Value (Hi)
4968 then
4969 return False;
4970 end if;
4972 -- Or are silly out of range of int bounds
4974 Lob := Expr_Value (Lo);
4975 Hib := Expr_Value (Hi);
4977 if not UI_Is_In_Int_Range (Lob)
4978 or else
4979 not UI_Is_In_Int_Range (Hib)
4980 then
4981 return False;
4982 end if;
4984 -- At this stage we have a suitable aggregate for handling
4985 -- at compile time (the only remaining checks, are that the
4986 -- values of expressions in the aggregate are compile time
4987 -- known (check performed by Get_Component_Val), and that
4988 -- any subtypes or ranges are statically known.
4990 -- If the aggregate is not fully positional at this stage,
4991 -- then convert it to positional form. Either this will fail,
4992 -- in which case we can do nothing, or it will succeed, in
4993 -- which case we have succeeded in handling the aggregate,
4994 -- or it will stay an aggregate, in which case we have failed
4995 -- to handle this case.
4997 if Present (Component_Associations (N)) then
4998 Convert_To_Positional
4999 (N, Max_Others_Replicate => 64, Handle_Bit_Packed => True);
5000 return Nkind (N) /= N_Aggregate;
5001 end if;
5003 -- Otherwise we are all positional, so convert to proper value
5005 declare
5006 Lov : constant Int := UI_To_Int (Lob);
5007 Hiv : constant Int := UI_To_Int (Hib);
5009 Len : constant Nat := Int'Max (0, Hiv - Lov + 1);
5010 -- The length of the array (number of elements)
5012 Aggregate_Val : Uint;
5013 -- Value of aggregate. The value is set in the low order
5014 -- bits of this value. For the little-endian case, the
5015 -- values are stored from low-order to high-order and
5016 -- for the big-endian case the values are stored from
5017 -- high-order to low-order. Note that gigi will take care
5018 -- of the conversions to left justify the value in the big
5019 -- endian case (because of left justified modular type
5020 -- processing), so we do not have to worry about that here.
5022 Lit : Node_Id;
5023 -- Integer literal for resulting constructed value
5025 Shift : Nat;
5026 -- Shift count from low order for next value
5028 Incr : Int;
5029 -- Shift increment for loop
5031 Expr : Node_Id;
5032 -- Next expression from positional parameters of aggregate
5034 begin
5035 -- For little endian, we fill up the low order bits of the
5036 -- target value. For big endian we fill up the high order
5037 -- bits of the target value (which is a left justified
5038 -- modular value).
5040 if Bytes_Big_Endian xor Debug_Flag_8 then
5041 Shift := Csiz * (Len - 1);
5042 Incr := -Csiz;
5043 else
5044 Shift := 0;
5045 Incr := +Csiz;
5046 end if;
5048 -- Loop to set the values
5050 if Len = 0 then
5051 Aggregate_Val := Uint_0;
5052 else
5053 Expr := First (Expressions (N));
5054 Aggregate_Val := Get_Component_Val (Expr) * Uint_2 ** Shift;
5056 for J in 2 .. Len loop
5057 Shift := Shift + Incr;
5058 Next (Expr);
5059 Aggregate_Val :=
5060 Aggregate_Val + Get_Component_Val (Expr) * Uint_2 ** Shift;
5061 end loop;
5062 end if;
5064 -- Now we can rewrite with the proper value
5066 Lit :=
5067 Make_Integer_Literal (Loc,
5068 Intval => Aggregate_Val);
5069 Set_Print_In_Hex (Lit);
5071 -- Construct the expression using this literal. Note that it is
5072 -- important to qualify the literal with its proper modular type
5073 -- since universal integer does not have the required range and
5074 -- also this is a left justified modular type, which is important
5075 -- in the big-endian case.
5077 Rewrite (N,
5078 Unchecked_Convert_To (Typ,
5079 Make_Qualified_Expression (Loc,
5080 Subtype_Mark =>
5081 New_Occurrence_Of (Packed_Array_Type (Typ), Loc),
5082 Expression => Lit)));
5084 Analyze_And_Resolve (N, Typ);
5085 return True;
5086 end;
5087 end;
5089 exception
5090 when Not_Handled =>
5091 return False;
5092 end Packed_Array_Aggregate_Handled;
5094 ----------------------------
5095 -- Has_Mutable_Components --
5096 ----------------------------
5098 function Has_Mutable_Components (Typ : Entity_Id) return Boolean is
5099 Comp : Entity_Id;
5101 begin
5102 Comp := First_Component (Typ);
5104 while Present (Comp) loop
5105 if Is_Record_Type (Etype (Comp))
5106 and then Has_Discriminants (Etype (Comp))
5107 and then not Is_Constrained (Etype (Comp))
5108 then
5109 return True;
5110 end if;
5112 Next_Component (Comp);
5113 end loop;
5115 return False;
5116 end Has_Mutable_Components;
5118 ------------------------------
5119 -- Initialize_Discriminants --
5120 ------------------------------
5122 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id) is
5123 Loc : constant Source_Ptr := Sloc (N);
5124 Bas : constant Entity_Id := Base_Type (Typ);
5125 Par : constant Entity_Id := Etype (Bas);
5126 Decl : constant Node_Id := Parent (Par);
5127 Ref : Node_Id;
5129 begin
5130 if Is_Tagged_Type (Bas)
5131 and then Is_Derived_Type (Bas)
5132 and then Has_Discriminants (Par)
5133 and then Has_Discriminants (Bas)
5134 and then Number_Discriminants (Bas) /= Number_Discriminants (Par)
5135 and then Nkind (Decl) = N_Full_Type_Declaration
5136 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
5137 and then Present
5138 (Variant_Part (Component_List (Type_Definition (Decl))))
5139 and then Nkind (N) /= N_Extension_Aggregate
5140 then
5142 -- Call init proc to set discriminants.
5143 -- There should eventually be a special procedure for this ???
5145 Ref := New_Reference_To (Defining_Identifier (N), Loc);
5146 Insert_Actions_After (N,
5147 Build_Initialization_Call (Sloc (N), Ref, Typ));
5148 end if;
5149 end Initialize_Discriminants;
5151 ----------------
5152 -- Must_Slide --
5153 ----------------
5155 function Must_Slide
5156 (Obj_Type : Entity_Id;
5157 Typ : Entity_Id) return Boolean
5159 L1, L2, H1, H2 : Node_Id;
5160 begin
5161 -- No sliding if the type of the object is not established yet, if
5162 -- it is an unconstrained type whose actual subtype comes from the
5163 -- aggregate, or if the two types are identical.
5165 if not Is_Array_Type (Obj_Type) then
5166 return False;
5168 elsif not Is_Constrained (Obj_Type) then
5169 return False;
5171 elsif Typ = Obj_Type then
5172 return False;
5174 else
5175 -- Sliding can only occur along the first dimension
5177 Get_Index_Bounds (First_Index (Typ), L1, H1);
5178 Get_Index_Bounds (First_Index (Obj_Type), L2, H2);
5180 if not Is_Static_Expression (L1)
5181 or else not Is_Static_Expression (L2)
5182 or else not Is_Static_Expression (H1)
5183 or else not Is_Static_Expression (H2)
5184 then
5185 return False;
5186 else
5187 return Expr_Value (L1) /= Expr_Value (L2)
5188 or else Expr_Value (H1) /= Expr_Value (H2);
5189 end if;
5190 end if;
5191 end Must_Slide;
5193 ---------------------------
5194 -- Safe_Slice_Assignment --
5195 ---------------------------
5197 function Safe_Slice_Assignment (N : Node_Id) return Boolean is
5198 Loc : constant Source_Ptr := Sloc (Parent (N));
5199 Pref : constant Node_Id := Prefix (Name (Parent (N)));
5200 Range_Node : constant Node_Id := Discrete_Range (Name (Parent (N)));
5201 Expr : Node_Id;
5202 L_J : Entity_Id;
5203 L_Iter : Node_Id;
5204 L_Body : Node_Id;
5205 Stat : Node_Id;
5207 begin
5208 -- Generate: for J in Range loop Pref (J) := Expr; end loop;
5210 if Comes_From_Source (N)
5211 and then No (Expressions (N))
5212 and then Nkind (First (Choices (First (Component_Associations (N)))))
5213 = N_Others_Choice
5214 then
5215 Expr :=
5216 Expression (First (Component_Associations (N)));
5217 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
5219 L_Iter :=
5220 Make_Iteration_Scheme (Loc,
5221 Loop_Parameter_Specification =>
5222 Make_Loop_Parameter_Specification
5223 (Loc,
5224 Defining_Identifier => L_J,
5225 Discrete_Subtype_Definition => Relocate_Node (Range_Node)));
5227 L_Body :=
5228 Make_Assignment_Statement (Loc,
5229 Name =>
5230 Make_Indexed_Component (Loc,
5231 Prefix => Relocate_Node (Pref),
5232 Expressions => New_List (New_Occurrence_Of (L_J, Loc))),
5233 Expression => Relocate_Node (Expr));
5235 -- Construct the final loop
5237 Stat :=
5238 Make_Implicit_Loop_Statement
5239 (Node => Parent (N),
5240 Identifier => Empty,
5241 Iteration_Scheme => L_Iter,
5242 Statements => New_List (L_Body));
5244 -- Set type of aggregate to be type of lhs in assignment,
5245 -- to suppress redundant length checks.
5247 Set_Etype (N, Etype (Name (Parent (N))));
5249 Rewrite (Parent (N), Stat);
5250 Analyze (Parent (N));
5251 return True;
5253 else
5254 return False;
5255 end if;
5256 end Safe_Slice_Assignment;
5258 ---------------------
5259 -- Sort_Case_Table --
5260 ---------------------
5262 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
5263 L : constant Int := Case_Table'First;
5264 U : constant Int := Case_Table'Last;
5265 K : Int;
5266 J : Int;
5267 T : Case_Bounds;
5269 begin
5270 K := L;
5272 while K /= U loop
5273 T := Case_Table (K + 1);
5274 J := K + 1;
5276 while J /= L
5277 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
5278 Expr_Value (T.Choice_Lo)
5279 loop
5280 Case_Table (J) := Case_Table (J - 1);
5281 J := J - 1;
5282 end loop;
5284 Case_Table (J) := T;
5285 K := K + 1;
5286 end loop;
5287 end Sort_Case_Table;
5289 end Exp_Aggr;