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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) 1992-2006, 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, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, 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 function Aggr_Size_OK (Typ : Entity_Id) return Boolean;
162 -- Very large static aggregates present problems to the back-end, and
163 -- are transformed into assignments and loops. This function verifies
164 -- that the total number of components of an aggregate is acceptable
165 -- for transformation into a purely positional static form. It is called
166 -- prior to calling Flatten.
168 procedure Convert_Array_Aggr_In_Allocator
169 (Decl : Node_Id;
170 Aggr : Node_Id;
171 Target : Node_Id);
172 -- If the aggregate appears within an allocator and can be expanded in
173 -- place, this routine generates the individual assignments to components
174 -- of the designated object. This is an optimization over the general
175 -- case, where a temporary is first created on the stack and then used to
176 -- construct the allocated object on the heap.
178 procedure Convert_To_Positional
179 (N : Node_Id;
180 Max_Others_Replicate : Nat := 5;
181 Handle_Bit_Packed : Boolean := False);
182 -- If possible, convert named notation to positional notation. This
183 -- conversion is possible only in some static cases. If the conversion is
184 -- possible, then N is rewritten with the analyzed converted aggregate.
185 -- The parameter Max_Others_Replicate controls the maximum number of
186 -- values corresponding to an others choice that will be converted to
187 -- positional notation (the default of 5 is the normal limit, and reflects
188 -- the fact that normally the loop is better than a lot of separate
189 -- assignments). Note that this limit gets overridden in any case if
190 -- either of the restrictions No_Elaboration_Code or No_Implicit_Loops is
191 -- set. The parameter Handle_Bit_Packed is usually set False (since we do
192 -- not expect the back end to handle bit packed arrays, so the normal case
193 -- of conversion is pointless), but in the special case of a call from
194 -- Packed_Array_Aggregate_Handled, we set this parameter to True, since
195 -- these are cases we handle in there.
197 procedure Expand_Array_Aggregate (N : Node_Id);
198 -- This is the top-level routine to perform array aggregate expansion.
199 -- N is the N_Aggregate node to be expanded.
201 function Backend_Processing_Possible (N : Node_Id) return Boolean;
202 -- This function checks if array aggregate N can be processed directly
203 -- by Gigi. If this is the case True is returned.
205 function Build_Array_Aggr_Code
206 (N : Node_Id;
207 Ctype : Entity_Id;
208 Index : Node_Id;
209 Into : Node_Id;
210 Scalar_Comp : Boolean;
211 Indices : List_Id := No_List;
212 Flist : Node_Id := Empty) return List_Id;
213 -- This recursive routine returns a list of statements containing the
214 -- loops and assignments that are needed for the expansion of the array
215 -- aggregate N.
217 -- N is the (sub-)aggregate node to be expanded into code. This node
218 -- has been fully analyzed, and its Etype is properly set.
220 -- Index is the index node corresponding to the array sub-aggregate N.
222 -- Into is the target expression into which we are copying the aggregate.
223 -- Note that this node may not have been analyzed yet, and so the Etype
224 -- field may not be set.
226 -- Scalar_Comp is True if the component type of the aggregate is scalar.
228 -- Indices is the current list of expressions used to index the
229 -- object we are writing into.
231 -- Flist is an expression representing the finalization list on which
232 -- to attach the controlled components if any.
234 function Number_Of_Choices (N : Node_Id) return Nat;
235 -- Returns the number of discrete choices (not including the others choice
236 -- if present) contained in (sub-)aggregate N.
238 function Late_Expansion
239 (N : Node_Id;
240 Typ : Entity_Id;
241 Target : Node_Id;
242 Flist : Node_Id := Empty;
243 Obj : Entity_Id := Empty) return List_Id;
244 -- N is a nested (record or array) aggregate that has been marked with
245 -- 'Delay_Expansion'. Typ is the expected type of the aggregate and Target
246 -- is a (duplicable) expression that will hold the result of the aggregate
247 -- expansion. Flist is the finalization list to be used to attach
248 -- controlled components. 'Obj' when non empty, carries the original
249 -- object being initialized in order to know if it needs to be attached to
250 -- the previous parameter which may not be the case in the case where
251 -- Finalize_Storage_Only is set. Basically this procedure is used to
252 -- implement top-down expansions of nested aggregates. This is necessary
253 -- for avoiding temporaries at each level as well as for propagating the
254 -- right internal finalization list.
256 function Make_OK_Assignment_Statement
257 (Sloc : Source_Ptr;
258 Name : Node_Id;
259 Expression : Node_Id) return Node_Id;
260 -- This is like Make_Assignment_Statement, except that Assignment_OK
261 -- is set in the left operand. All assignments built by this unit
262 -- use this routine. This is needed to deal with assignments to
263 -- initialized constants that are done in place.
265 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean;
266 -- Given an array aggregate, this function handles the case of a packed
267 -- array aggregate with all constant values, where the aggregate can be
268 -- evaluated at compile time. If this is possible, then N is rewritten
269 -- to be its proper compile time value with all the components properly
270 -- assembled. The expression is analyzed and resolved and True is
271 -- returned. If this transformation is not possible, N is unchanged
272 -- and False is returned
274 function Safe_Slice_Assignment (N : Node_Id) return Boolean;
275 -- If a slice assignment has an aggregate with a single others_choice,
276 -- the assignment can be done in place even if bounds are not static,
277 -- by converting it into a loop over the discrete range of the slice.
279 ------------------
280 -- Aggr_Size_OK --
281 ------------------
283 function Aggr_Size_OK (Typ : Entity_Id) return Boolean is
284 Lo : Node_Id;
285 Hi : Node_Id;
286 Indx : Node_Id;
287 Siz : Int;
288 Lov : Uint;
289 Hiv : Uint;
291 -- The following constant determines the maximum size of an
292 -- aggregate produced by converting named to positional
293 -- notation (e.g. from others clauses). This avoids running
294 -- away with attempts to convert huge aggregates, which hit
295 -- memory limits in the backend.
297 -- The normal limit is 5000, but we increase this limit to
298 -- 2**24 (about 16 million) if Restrictions (No_Elaboration_Code)
299 -- or Restrictions (No_Implicit_Loops) is specified, since in
300 -- either case, we are at risk of declaring the program illegal
301 -- because of this limit.
303 Max_Aggr_Size : constant Nat :=
304 5000 + (2 ** 24 - 5000) *
305 Boolean'Pos
306 (Restriction_Active (No_Elaboration_Code)
307 or else
308 Restriction_Active (No_Implicit_Loops));
310 function Component_Count (T : Entity_Id) return Int;
311 -- The limit is applied to the total number of components that the
312 -- aggregate will have, which is the number of static expressions
313 -- that will appear in the flattened array. This requires a recursive
314 -- computation of the the number of scalar components of the structure.
316 ---------------------
317 -- Component_Count --
318 ---------------------
320 function Component_Count (T : Entity_Id) return Int is
321 Res : Int := 0;
322 Comp : Entity_Id;
324 begin
325 if Is_Scalar_Type (T) then
326 return 1;
328 elsif Is_Record_Type (T) then
329 Comp := First_Component (T);
330 while Present (Comp) loop
331 Res := Res + Component_Count (Etype (Comp));
332 Next_Component (Comp);
333 end loop;
335 return Res;
337 elsif Is_Array_Type (T) then
338 declare
339 Lo : constant Node_Id :=
340 Type_Low_Bound (Etype (First_Index (T)));
341 Hi : constant Node_Id :=
342 Type_High_Bound (Etype (First_Index (T)));
344 Siz : constant Int := Component_Count (Component_Type (T));
346 begin
347 if not Compile_Time_Known_Value (Lo)
348 or else not Compile_Time_Known_Value (Hi)
349 then
350 return 0;
351 else
352 return
353 Siz * UI_To_Int (Expr_Value (Hi) - Expr_Value (Lo) + 1);
354 end if;
355 end;
357 else
358 -- Can only be a null for an access type
360 return 1;
361 end if;
362 end Component_Count;
364 -- Start of processing for Aggr_Size_OK
366 begin
367 Siz := Component_Count (Component_Type (Typ));
368 Indx := First_Index (Typ);
370 while Present (Indx) loop
371 Lo := Type_Low_Bound (Etype (Indx));
372 Hi := Type_High_Bound (Etype (Indx));
374 -- Bounds need to be known at compile time
376 if not Compile_Time_Known_Value (Lo)
377 or else not Compile_Time_Known_Value (Hi)
378 then
379 return False;
380 end if;
382 Lov := Expr_Value (Lo);
383 Hiv := Expr_Value (Hi);
385 -- A flat array is always safe
387 if Hiv < Lov then
388 return True;
389 end if;
391 declare
392 Rng : constant Uint := Hiv - Lov + 1;
394 begin
395 -- Check if size is too large
397 if not UI_Is_In_Int_Range (Rng) then
398 return False;
399 end if;
401 Siz := Siz * UI_To_Int (Rng);
402 end;
404 if Siz <= 0
405 or else Siz > Max_Aggr_Size
406 then
407 return False;
408 end if;
410 -- Bounds must be in integer range, for later array construction
412 if not UI_Is_In_Int_Range (Lov)
413 or else
414 not UI_Is_In_Int_Range (Hiv)
415 then
416 return False;
417 end if;
419 Next_Index (Indx);
420 end loop;
422 return True;
423 end Aggr_Size_OK;
425 ---------------------------------
426 -- Backend_Processing_Possible --
427 ---------------------------------
429 -- Backend processing by Gigi/gcc is possible only if all the following
430 -- conditions are met:
432 -- 1. N is fully positional
434 -- 2. N is not a bit-packed array aggregate;
436 -- 3. The size of N's array type must be known at compile time. Note
437 -- that this implies that the component size is also known
439 -- 4. The array type of N does not follow the Fortran layout convention
440 -- or if it does it must be 1 dimensional.
442 -- 5. The array component type is tagged, which may necessitate
443 -- reassignment of proper tags.
445 -- 6. The array component type might have unaligned bit components
447 function Backend_Processing_Possible (N : Node_Id) return Boolean is
448 Typ : constant Entity_Id := Etype (N);
449 -- Typ is the correct constrained array subtype of the aggregate
451 function Static_Check (N : Node_Id; Index : Node_Id) return Boolean;
452 -- Recursively checks that N is fully positional, returns true if so
454 ------------------
455 -- Static_Check --
456 ------------------
458 function Static_Check (N : Node_Id; Index : Node_Id) return Boolean is
459 Expr : Node_Id;
461 begin
462 -- Check for component associations
464 if Present (Component_Associations (N)) then
465 return False;
466 end if;
468 -- Recurse to check subaggregates, which may appear in qualified
469 -- expressions. If delayed, the front-end will have to expand.
471 Expr := First (Expressions (N));
473 while Present (Expr) loop
475 if Is_Delayed_Aggregate (Expr) then
476 return False;
477 end if;
479 if Present (Next_Index (Index))
480 and then not Static_Check (Expr, Next_Index (Index))
481 then
482 return False;
483 end if;
485 Next (Expr);
486 end loop;
488 return True;
489 end Static_Check;
491 -- Start of processing for Backend_Processing_Possible
493 begin
494 -- Checks 2 (array must not be bit packed)
496 if Is_Bit_Packed_Array (Typ) then
497 return False;
498 end if;
500 -- Checks 4 (array must not be multi-dimensional Fortran case)
502 if Convention (Typ) = Convention_Fortran
503 and then Number_Dimensions (Typ) > 1
504 then
505 return False;
506 end if;
508 -- Checks 3 (size of array must be known at compile time)
510 if not Size_Known_At_Compile_Time (Typ) then
511 return False;
512 end if;
514 -- Checks 1 (aggregate must be fully positional)
516 if not Static_Check (N, First_Index (Typ)) then
517 return False;
518 end if;
520 -- Checks 5 (if the component type is tagged, then we may need
521 -- to do tag adjustments; perhaps this should be refined to check for
522 -- any component associations that actually need tag adjustment,
523 -- along the lines of the test that is carried out in
524 -- Has_Delayed_Nested_Aggregate_Or_Tagged_Comps for record aggregates
525 -- with tagged components, but not clear whether it's worthwhile ???;
526 -- in the case of the JVM, object tags are handled implicitly)
528 if Is_Tagged_Type (Component_Type (Typ)) and then not Java_VM then
529 return False;
530 end if;
532 -- Checks 6 (component type must not have bit aligned components)
534 if Type_May_Have_Bit_Aligned_Components (Component_Type (Typ)) then
535 return False;
536 end if;
538 -- Backend processing is possible
540 Set_Compile_Time_Known_Aggregate (N, True);
541 Set_Size_Known_At_Compile_Time (Etype (N), True);
542 return True;
543 end Backend_Processing_Possible;
545 ---------------------------
546 -- Build_Array_Aggr_Code --
547 ---------------------------
549 -- The code that we generate from a one dimensional aggregate is
551 -- 1. If the sub-aggregate contains discrete choices we
553 -- (a) Sort the discrete choices
555 -- (b) Otherwise for each discrete choice that specifies a range we
556 -- emit a loop. If a range specifies a maximum of three values, or
557 -- we are dealing with an expression we emit a sequence of
558 -- assignments instead of a loop.
560 -- (c) Generate the remaining loops to cover the others choice if any
562 -- 2. If the aggregate contains positional elements we
564 -- (a) translate the positional elements in a series of assignments
566 -- (b) Generate a final loop to cover the others choice if any.
567 -- Note that this final loop has to be a while loop since the case
569 -- L : Integer := Integer'Last;
570 -- H : Integer := Integer'Last;
571 -- A : array (L .. H) := (1, others =>0);
573 -- cannot be handled by a for loop. Thus for the following
575 -- array (L .. H) := (.. positional elements.., others =>E);
577 -- we always generate something like:
579 -- J : Index_Type := Index_Of_Last_Positional_Element;
580 -- while J < H loop
581 -- J := Index_Base'Succ (J)
582 -- Tmp (J) := E;
583 -- end loop;
585 function Build_Array_Aggr_Code
586 (N : Node_Id;
587 Ctype : Entity_Id;
588 Index : Node_Id;
589 Into : Node_Id;
590 Scalar_Comp : Boolean;
591 Indices : List_Id := No_List;
592 Flist : Node_Id := Empty) return List_Id
594 Loc : constant Source_Ptr := Sloc (N);
595 Index_Base : constant Entity_Id := Base_Type (Etype (Index));
596 Index_Base_L : constant Node_Id := Type_Low_Bound (Index_Base);
597 Index_Base_H : constant Node_Id := Type_High_Bound (Index_Base);
599 function Add (Val : Int; To : Node_Id) return Node_Id;
600 -- Returns an expression where Val is added to expression To, unless
601 -- To+Val is provably out of To's base type range. To must be an
602 -- already analyzed expression.
604 function Empty_Range (L, H : Node_Id) return Boolean;
605 -- Returns True if the range defined by L .. H is certainly empty
607 function Equal (L, H : Node_Id) return Boolean;
608 -- Returns True if L = H for sure
610 function Index_Base_Name return Node_Id;
611 -- Returns a new reference to the index type name
613 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id;
614 -- Ind must be a side-effect free expression. If the input aggregate
615 -- N to Build_Loop contains no sub-aggregates, then this function
616 -- returns the assignment statement:
618 -- Into (Indices, Ind) := Expr;
620 -- Otherwise we call Build_Code recursively
622 -- Ada 2005 (AI-287): In case of default initialized component, Expr
623 -- is empty and we generate a call to the corresponding IP subprogram.
625 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id;
626 -- Nodes L and H must be side-effect free expressions.
627 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
628 -- This routine returns the for loop statement
630 -- for J in Index_Base'(L) .. Index_Base'(H) loop
631 -- Into (Indices, J) := Expr;
632 -- end loop;
634 -- Otherwise we call Build_Code recursively.
635 -- As an optimization if the loop covers 3 or less scalar elements we
636 -- generate a sequence of assignments.
638 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id;
639 -- Nodes L and H must be side-effect free expressions.
640 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
641 -- This routine returns the while loop statement
643 -- J : Index_Base := L;
644 -- while J < H loop
645 -- J := Index_Base'Succ (J);
646 -- Into (Indices, J) := Expr;
647 -- end loop;
649 -- Otherwise we call Build_Code recursively
651 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean;
652 function Local_Expr_Value (E : Node_Id) return Uint;
653 -- These two Local routines are used to replace the corresponding ones
654 -- in sem_eval because while processing the bounds of an aggregate with
655 -- discrete choices whose index type is an enumeration, we build static
656 -- expressions not recognized by Compile_Time_Known_Value as such since
657 -- they have not yet been analyzed and resolved. All the expressions in
658 -- question are things like Index_Base_Name'Val (Const) which we can
659 -- easily recognize as being constant.
661 ---------
662 -- Add --
663 ---------
665 function Add (Val : Int; To : Node_Id) return Node_Id is
666 Expr_Pos : Node_Id;
667 Expr : Node_Id;
668 To_Pos : Node_Id;
669 U_To : Uint;
670 U_Val : constant Uint := UI_From_Int (Val);
672 begin
673 -- Note: do not try to optimize the case of Val = 0, because
674 -- we need to build a new node with the proper Sloc value anyway.
676 -- First test if we can do constant folding
678 if Local_Compile_Time_Known_Value (To) then
679 U_To := Local_Expr_Value (To) + Val;
681 -- Determine if our constant is outside the range of the index.
682 -- If so return an Empty node. This empty node will be caught
683 -- by Empty_Range below.
685 if Compile_Time_Known_Value (Index_Base_L)
686 and then U_To < Expr_Value (Index_Base_L)
687 then
688 return Empty;
690 elsif Compile_Time_Known_Value (Index_Base_H)
691 and then U_To > Expr_Value (Index_Base_H)
692 then
693 return Empty;
694 end if;
696 Expr_Pos := Make_Integer_Literal (Loc, U_To);
697 Set_Is_Static_Expression (Expr_Pos);
699 if not Is_Enumeration_Type (Index_Base) then
700 Expr := Expr_Pos;
702 -- If we are dealing with enumeration return
703 -- Index_Base'Val (Expr_Pos)
705 else
706 Expr :=
707 Make_Attribute_Reference
708 (Loc,
709 Prefix => Index_Base_Name,
710 Attribute_Name => Name_Val,
711 Expressions => New_List (Expr_Pos));
712 end if;
714 return Expr;
715 end if;
717 -- If we are here no constant folding possible
719 if not Is_Enumeration_Type (Index_Base) then
720 Expr :=
721 Make_Op_Add (Loc,
722 Left_Opnd => Duplicate_Subexpr (To),
723 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
725 -- If we are dealing with enumeration return
726 -- Index_Base'Val (Index_Base'Pos (To) + Val)
728 else
729 To_Pos :=
730 Make_Attribute_Reference
731 (Loc,
732 Prefix => Index_Base_Name,
733 Attribute_Name => Name_Pos,
734 Expressions => New_List (Duplicate_Subexpr (To)));
736 Expr_Pos :=
737 Make_Op_Add (Loc,
738 Left_Opnd => To_Pos,
739 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
741 Expr :=
742 Make_Attribute_Reference
743 (Loc,
744 Prefix => Index_Base_Name,
745 Attribute_Name => Name_Val,
746 Expressions => New_List (Expr_Pos));
747 end if;
749 return Expr;
750 end Add;
752 -----------------
753 -- Empty_Range --
754 -----------------
756 function Empty_Range (L, H : Node_Id) return Boolean is
757 Is_Empty : Boolean := False;
758 Low : Node_Id;
759 High : Node_Id;
761 begin
762 -- First check if L or H were already detected as overflowing the
763 -- index base range type by function Add above. If this is so Add
764 -- returns the empty node.
766 if No (L) or else No (H) then
767 return True;
768 end if;
770 for J in 1 .. 3 loop
771 case J is
773 -- L > H range is empty
775 when 1 =>
776 Low := L;
777 High := H;
779 -- B_L > H range must be empty
781 when 2 =>
782 Low := Index_Base_L;
783 High := H;
785 -- L > B_H range must be empty
787 when 3 =>
788 Low := L;
789 High := Index_Base_H;
790 end case;
792 if Local_Compile_Time_Known_Value (Low)
793 and then Local_Compile_Time_Known_Value (High)
794 then
795 Is_Empty :=
796 UI_Gt (Local_Expr_Value (Low), Local_Expr_Value (High));
797 end if;
799 exit when Is_Empty;
800 end loop;
802 return Is_Empty;
803 end Empty_Range;
805 -----------
806 -- Equal --
807 -----------
809 function Equal (L, H : Node_Id) return Boolean is
810 begin
811 if L = H then
812 return True;
814 elsif Local_Compile_Time_Known_Value (L)
815 and then Local_Compile_Time_Known_Value (H)
816 then
817 return UI_Eq (Local_Expr_Value (L), Local_Expr_Value (H));
818 end if;
820 return False;
821 end Equal;
823 ----------------
824 -- Gen_Assign --
825 ----------------
827 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id is
828 L : constant List_Id := New_List;
829 F : Entity_Id;
830 A : Node_Id;
832 New_Indices : List_Id;
833 Indexed_Comp : Node_Id;
834 Expr_Q : Node_Id;
835 Comp_Type : Entity_Id := Empty;
837 function Add_Loop_Actions (Lis : List_Id) return List_Id;
838 -- Collect insert_actions generated in the construction of a
839 -- loop, and prepend them to the sequence of assignments to
840 -- complete the eventual body of the loop.
842 ----------------------
843 -- Add_Loop_Actions --
844 ----------------------
846 function Add_Loop_Actions (Lis : List_Id) return List_Id is
847 Res : List_Id;
849 begin
850 -- Ada 2005 (AI-287): Do nothing else in case of default
851 -- initialized component.
853 if No (Expr) then
854 return Lis;
856 elsif Nkind (Parent (Expr)) = N_Component_Association
857 and then Present (Loop_Actions (Parent (Expr)))
858 then
859 Append_List (Lis, Loop_Actions (Parent (Expr)));
860 Res := Loop_Actions (Parent (Expr));
861 Set_Loop_Actions (Parent (Expr), No_List);
862 return Res;
864 else
865 return Lis;
866 end if;
867 end Add_Loop_Actions;
869 -- Start of processing for Gen_Assign
871 begin
872 if No (Indices) then
873 New_Indices := New_List;
874 else
875 New_Indices := New_Copy_List_Tree (Indices);
876 end if;
878 Append_To (New_Indices, Ind);
880 if Present (Flist) then
881 F := New_Copy_Tree (Flist);
883 elsif Present (Etype (N)) and then Controlled_Type (Etype (N)) then
884 if Is_Entity_Name (Into)
885 and then Present (Scope (Entity (Into)))
886 then
887 F := Find_Final_List (Scope (Entity (Into)));
888 else
889 F := Find_Final_List (Current_Scope);
890 end if;
891 else
892 F := Empty;
893 end if;
895 if Present (Next_Index (Index)) then
896 return
897 Add_Loop_Actions (
898 Build_Array_Aggr_Code
899 (N => Expr,
900 Ctype => Ctype,
901 Index => Next_Index (Index),
902 Into => Into,
903 Scalar_Comp => Scalar_Comp,
904 Indices => New_Indices,
905 Flist => F));
906 end if;
908 -- If we get here then we are at a bottom-level (sub-)aggregate
910 Indexed_Comp :=
911 Checks_Off
912 (Make_Indexed_Component (Loc,
913 Prefix => New_Copy_Tree (Into),
914 Expressions => New_Indices));
916 Set_Assignment_OK (Indexed_Comp);
918 -- Ada 2005 (AI-287): In case of default initialized component, Expr
919 -- is not present (and therefore we also initialize Expr_Q to empty).
921 if No (Expr) then
922 Expr_Q := Empty;
923 elsif Nkind (Expr) = N_Qualified_Expression then
924 Expr_Q := Expression (Expr);
925 else
926 Expr_Q := Expr;
927 end if;
929 if Present (Etype (N))
930 and then Etype (N) /= Any_Composite
931 then
932 Comp_Type := Component_Type (Etype (N));
933 pragma Assert (Comp_Type = Ctype); -- AI-287
935 elsif Present (Next (First (New_Indices))) then
937 -- Ada 2005 (AI-287): Do nothing in case of default initialized
938 -- component because we have received the component type in
939 -- the formal parameter Ctype.
941 -- ??? Some assert pragmas have been added to check if this new
942 -- formal can be used to replace this code in all cases.
944 if Present (Expr) then
946 -- This is a multidimensional array. Recover the component
947 -- type from the outermost aggregate, because subaggregates
948 -- do not have an assigned type.
950 declare
951 P : Node_Id := Parent (Expr);
953 begin
954 while Present (P) loop
955 if Nkind (P) = N_Aggregate
956 and then Present (Etype (P))
957 then
958 Comp_Type := Component_Type (Etype (P));
959 exit;
961 else
962 P := Parent (P);
963 end if;
964 end loop;
966 pragma Assert (Comp_Type = Ctype); -- AI-287
967 end;
968 end if;
969 end if;
971 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
972 -- default initialized components (otherwise Expr_Q is not present).
974 if Present (Expr_Q)
975 and then (Nkind (Expr_Q) = N_Aggregate
976 or else Nkind (Expr_Q) = N_Extension_Aggregate)
977 then
978 -- At this stage the Expression may not have been
979 -- analyzed yet because the array aggregate code has not
980 -- been updated to use the Expansion_Delayed flag and
981 -- avoid analysis altogether to solve the same problem
982 -- (see Resolve_Aggr_Expr). So let us do the analysis of
983 -- non-array aggregates now in order to get the value of
984 -- Expansion_Delayed flag for the inner aggregate ???
986 if Present (Comp_Type) and then not Is_Array_Type (Comp_Type) then
987 Analyze_And_Resolve (Expr_Q, Comp_Type);
988 end if;
990 if Is_Delayed_Aggregate (Expr_Q) then
992 -- This is either a subaggregate of a multidimentional array,
993 -- or a component of an array type whose component type is
994 -- also an array. In the latter case, the expression may have
995 -- component associations that provide different bounds from
996 -- those of the component type, and sliding must occur. Instead
997 -- of decomposing the current aggregate assignment, force the
998 -- re-analysis of the assignment, so that a temporary will be
999 -- generated in the usual fashion, and sliding will take place.
1001 if Nkind (Parent (N)) = N_Assignment_Statement
1002 and then Is_Array_Type (Comp_Type)
1003 and then Present (Component_Associations (Expr_Q))
1004 and then Must_Slide (Comp_Type, Etype (Expr_Q))
1005 then
1006 Set_Expansion_Delayed (Expr_Q, False);
1007 Set_Analyzed (Expr_Q, False);
1009 else
1010 return
1011 Add_Loop_Actions (
1012 Late_Expansion (
1013 Expr_Q, Etype (Expr_Q), Indexed_Comp, F));
1014 end if;
1015 end if;
1016 end if;
1018 -- Ada 2005 (AI-287): In case of default initialized component, call
1019 -- the initialization subprogram associated with the component type.
1021 if No (Expr) then
1022 if Present (Base_Init_Proc (Etype (Ctype)))
1023 or else Has_Task (Base_Type (Ctype))
1024 then
1025 Append_List_To (L,
1026 Build_Initialization_Call (Loc,
1027 Id_Ref => Indexed_Comp,
1028 Typ => Ctype,
1029 With_Default_Init => True));
1030 end if;
1032 else
1033 -- Now generate the assignment with no associated controlled
1034 -- actions since the target of the assignment may not have
1035 -- been initialized, it is not possible to Finalize it as
1036 -- expected by normal controlled assignment. The rest of the
1037 -- controlled actions are done manually with the proper
1038 -- finalization list coming from the context.
1040 A :=
1041 Make_OK_Assignment_Statement (Loc,
1042 Name => Indexed_Comp,
1043 Expression => New_Copy_Tree (Expr));
1045 if Present (Comp_Type) and then Controlled_Type (Comp_Type) then
1046 Set_No_Ctrl_Actions (A);
1048 -- If this is an aggregate for an array of arrays, each
1049 -- subaggregate will be expanded as well, and even with
1050 -- No_Ctrl_Actions the assignments of inner components will
1051 -- require attachment in their assignments to temporaries.
1052 -- These temporaries must be finalized for each subaggregate,
1053 -- to prevent multiple attachments of the same temporary
1054 -- location to same finalization chain (and consequently
1055 -- circular lists). To ensure that finalization takes place
1056 -- for each subaggregate we wrap the assignment in a block.
1058 if Is_Array_Type (Comp_Type)
1059 and then Nkind (Expr) = N_Aggregate
1060 then
1061 A :=
1062 Make_Block_Statement (Loc,
1063 Handled_Statement_Sequence =>
1064 Make_Handled_Sequence_Of_Statements (Loc,
1065 Statements => New_List (A)));
1066 end if;
1067 end if;
1069 Append_To (L, A);
1071 -- Adjust the tag if tagged (because of possible view
1072 -- conversions), unless compiling for the Java VM
1073 -- where tags are implicit.
1075 if Present (Comp_Type)
1076 and then Is_Tagged_Type (Comp_Type)
1077 and then not Java_VM
1078 then
1079 A :=
1080 Make_OK_Assignment_Statement (Loc,
1081 Name =>
1082 Make_Selected_Component (Loc,
1083 Prefix => New_Copy_Tree (Indexed_Comp),
1084 Selector_Name =>
1085 New_Reference_To
1086 (First_Tag_Component (Comp_Type), Loc)),
1088 Expression =>
1089 Unchecked_Convert_To (RTE (RE_Tag),
1090 New_Reference_To
1091 (Node (First_Elmt (Access_Disp_Table (Comp_Type))),
1092 Loc)));
1094 Append_To (L, A);
1095 end if;
1097 -- Adjust and Attach the component to the proper final list
1098 -- which can be the controller of the outer record object or
1099 -- the final list associated with the scope
1101 if Present (Comp_Type) and then Controlled_Type (Comp_Type) then
1102 Append_List_To (L,
1103 Make_Adjust_Call (
1104 Ref => New_Copy_Tree (Indexed_Comp),
1105 Typ => Comp_Type,
1106 Flist_Ref => F,
1107 With_Attach => Make_Integer_Literal (Loc, 1)));
1108 end if;
1109 end if;
1111 return Add_Loop_Actions (L);
1112 end Gen_Assign;
1114 --------------
1115 -- Gen_Loop --
1116 --------------
1118 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id is
1119 L_J : Node_Id;
1121 L_Range : Node_Id;
1122 -- Index_Base'(L) .. Index_Base'(H)
1124 L_Iteration_Scheme : Node_Id;
1125 -- L_J in Index_Base'(L) .. Index_Base'(H)
1127 L_Body : List_Id;
1128 -- The statements to execute in the loop
1130 S : constant List_Id := New_List;
1131 -- List of statements
1133 Tcopy : Node_Id;
1134 -- Copy of expression tree, used for checking purposes
1136 begin
1137 -- If loop bounds define an empty range return the null statement
1139 if Empty_Range (L, H) then
1140 Append_To (S, Make_Null_Statement (Loc));
1142 -- Ada 2005 (AI-287): Nothing else need to be done in case of
1143 -- default initialized component.
1145 if No (Expr) then
1146 null;
1148 else
1149 -- The expression must be type-checked even though no component
1150 -- of the aggregate will have this value. This is done only for
1151 -- actual components of the array, not for subaggregates. Do
1152 -- the check on a copy, because the expression may be shared
1153 -- among several choices, some of which might be non-null.
1155 if Present (Etype (N))
1156 and then Is_Array_Type (Etype (N))
1157 and then No (Next_Index (Index))
1158 then
1159 Expander_Mode_Save_And_Set (False);
1160 Tcopy := New_Copy_Tree (Expr);
1161 Set_Parent (Tcopy, N);
1162 Analyze_And_Resolve (Tcopy, Component_Type (Etype (N)));
1163 Expander_Mode_Restore;
1164 end if;
1165 end if;
1167 return S;
1169 -- If loop bounds are the same then generate an assignment
1171 elsif Equal (L, H) then
1172 return Gen_Assign (New_Copy_Tree (L), Expr);
1174 -- If H - L <= 2 then generate a sequence of assignments
1175 -- when we are processing the bottom most aggregate and it contains
1176 -- scalar components.
1178 elsif No (Next_Index (Index))
1179 and then Scalar_Comp
1180 and then Local_Compile_Time_Known_Value (L)
1181 and then Local_Compile_Time_Known_Value (H)
1182 and then Local_Expr_Value (H) - Local_Expr_Value (L) <= 2
1183 then
1185 Append_List_To (S, Gen_Assign (New_Copy_Tree (L), Expr));
1186 Append_List_To (S, Gen_Assign (Add (1, To => L), Expr));
1188 if Local_Expr_Value (H) - Local_Expr_Value (L) = 2 then
1189 Append_List_To (S, Gen_Assign (Add (2, To => L), Expr));
1190 end if;
1192 return S;
1193 end if;
1195 -- Otherwise construct the loop, starting with the loop index L_J
1197 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
1199 -- Construct "L .. H"
1201 L_Range :=
1202 Make_Range
1203 (Loc,
1204 Low_Bound => Make_Qualified_Expression
1205 (Loc,
1206 Subtype_Mark => Index_Base_Name,
1207 Expression => L),
1208 High_Bound => Make_Qualified_Expression
1209 (Loc,
1210 Subtype_Mark => Index_Base_Name,
1211 Expression => H));
1213 -- Construct "for L_J in Index_Base range L .. H"
1215 L_Iteration_Scheme :=
1216 Make_Iteration_Scheme
1217 (Loc,
1218 Loop_Parameter_Specification =>
1219 Make_Loop_Parameter_Specification
1220 (Loc,
1221 Defining_Identifier => L_J,
1222 Discrete_Subtype_Definition => L_Range));
1224 -- Construct the statements to execute in the loop body
1226 L_Body := Gen_Assign (New_Reference_To (L_J, Loc), Expr);
1228 -- Construct the final loop
1230 Append_To (S, Make_Implicit_Loop_Statement
1231 (Node => N,
1232 Identifier => Empty,
1233 Iteration_Scheme => L_Iteration_Scheme,
1234 Statements => L_Body));
1236 return S;
1237 end Gen_Loop;
1239 ---------------
1240 -- Gen_While --
1241 ---------------
1243 -- The code built is
1245 -- W_J : Index_Base := L;
1246 -- while W_J < H loop
1247 -- W_J := Index_Base'Succ (W);
1248 -- L_Body;
1249 -- end loop;
1251 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id is
1252 W_J : Node_Id;
1254 W_Decl : Node_Id;
1255 -- W_J : Base_Type := L;
1257 W_Iteration_Scheme : Node_Id;
1258 -- while W_J < H
1260 W_Index_Succ : Node_Id;
1261 -- Index_Base'Succ (J)
1263 W_Increment : Node_Id;
1264 -- W_J := Index_Base'Succ (W)
1266 W_Body : constant List_Id := New_List;
1267 -- The statements to execute in the loop
1269 S : constant List_Id := New_List;
1270 -- list of statement
1272 begin
1273 -- If loop bounds define an empty range or are equal return null
1275 if Empty_Range (L, H) or else Equal (L, H) then
1276 Append_To (S, Make_Null_Statement (Loc));
1277 return S;
1278 end if;
1280 -- Build the decl of W_J
1282 W_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
1283 W_Decl :=
1284 Make_Object_Declaration
1285 (Loc,
1286 Defining_Identifier => W_J,
1287 Object_Definition => Index_Base_Name,
1288 Expression => L);
1290 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1291 -- that in this particular case L is a fresh Expr generated by
1292 -- Add which we are the only ones to use.
1294 Append_To (S, W_Decl);
1296 -- Construct " while W_J < H"
1298 W_Iteration_Scheme :=
1299 Make_Iteration_Scheme
1300 (Loc,
1301 Condition => Make_Op_Lt
1302 (Loc,
1303 Left_Opnd => New_Reference_To (W_J, Loc),
1304 Right_Opnd => New_Copy_Tree (H)));
1306 -- Construct the statements to execute in the loop body
1308 W_Index_Succ :=
1309 Make_Attribute_Reference
1310 (Loc,
1311 Prefix => Index_Base_Name,
1312 Attribute_Name => Name_Succ,
1313 Expressions => New_List (New_Reference_To (W_J, Loc)));
1315 W_Increment :=
1316 Make_OK_Assignment_Statement
1317 (Loc,
1318 Name => New_Reference_To (W_J, Loc),
1319 Expression => W_Index_Succ);
1321 Append_To (W_Body, W_Increment);
1322 Append_List_To (W_Body,
1323 Gen_Assign (New_Reference_To (W_J, Loc), Expr));
1325 -- Construct the final loop
1327 Append_To (S, Make_Implicit_Loop_Statement
1328 (Node => N,
1329 Identifier => Empty,
1330 Iteration_Scheme => W_Iteration_Scheme,
1331 Statements => W_Body));
1333 return S;
1334 end Gen_While;
1336 ---------------------
1337 -- Index_Base_Name --
1338 ---------------------
1340 function Index_Base_Name return Node_Id is
1341 begin
1342 return New_Reference_To (Index_Base, Sloc (N));
1343 end Index_Base_Name;
1345 ------------------------------------
1346 -- Local_Compile_Time_Known_Value --
1347 ------------------------------------
1349 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean is
1350 begin
1351 return Compile_Time_Known_Value (E)
1352 or else
1353 (Nkind (E) = N_Attribute_Reference
1354 and then Attribute_Name (E) = Name_Val
1355 and then Compile_Time_Known_Value (First (Expressions (E))));
1356 end Local_Compile_Time_Known_Value;
1358 ----------------------
1359 -- Local_Expr_Value --
1360 ----------------------
1362 function Local_Expr_Value (E : Node_Id) return Uint is
1363 begin
1364 if Compile_Time_Known_Value (E) then
1365 return Expr_Value (E);
1366 else
1367 return Expr_Value (First (Expressions (E)));
1368 end if;
1369 end Local_Expr_Value;
1371 -- Build_Array_Aggr_Code Variables
1373 Assoc : Node_Id;
1374 Choice : Node_Id;
1375 Expr : Node_Id;
1376 Typ : Entity_Id;
1378 Others_Expr : Node_Id := Empty;
1379 Others_Box_Present : Boolean := False;
1381 Aggr_L : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
1382 Aggr_H : constant Node_Id := High_Bound (Aggregate_Bounds (N));
1383 -- The aggregate bounds of this specific sub-aggregate. Note that if
1384 -- the code generated by Build_Array_Aggr_Code is executed then these
1385 -- bounds are OK. Otherwise a Constraint_Error would have been raised.
1387 Aggr_Low : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_L);
1388 Aggr_High : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_H);
1389 -- After Duplicate_Subexpr these are side-effect free
1391 Low : Node_Id;
1392 High : Node_Id;
1394 Nb_Choices : Nat := 0;
1395 Table : Case_Table_Type (1 .. Number_Of_Choices (N));
1396 -- Used to sort all the different choice values
1398 Nb_Elements : Int;
1399 -- Number of elements in the positional aggregate
1401 New_Code : constant List_Id := New_List;
1403 -- Start of processing for Build_Array_Aggr_Code
1405 begin
1406 -- First before we start, a special case. if we have a bit packed
1407 -- array represented as a modular type, then clear the value to
1408 -- zero first, to ensure that unused bits are properly cleared.
1410 Typ := Etype (N);
1412 if Present (Typ)
1413 and then Is_Bit_Packed_Array (Typ)
1414 and then Is_Modular_Integer_Type (Packed_Array_Type (Typ))
1415 then
1416 Append_To (New_Code,
1417 Make_Assignment_Statement (Loc,
1418 Name => New_Copy_Tree (Into),
1419 Expression =>
1420 Unchecked_Convert_To (Typ,
1421 Make_Integer_Literal (Loc, Uint_0))));
1422 end if;
1424 -- We can skip this
1425 -- STEP 1: Process component associations
1426 -- For those associations that may generate a loop, initialize
1427 -- Loop_Actions to collect inserted actions that may be crated.
1429 if No (Expressions (N)) then
1431 -- STEP 1 (a): Sort the discrete choices
1433 Assoc := First (Component_Associations (N));
1434 while Present (Assoc) loop
1435 Choice := First (Choices (Assoc));
1436 while Present (Choice) loop
1437 if Nkind (Choice) = N_Others_Choice then
1438 Set_Loop_Actions (Assoc, New_List);
1440 if Box_Present (Assoc) then
1441 Others_Box_Present := True;
1442 else
1443 Others_Expr := Expression (Assoc);
1444 end if;
1445 exit;
1446 end if;
1448 Get_Index_Bounds (Choice, Low, High);
1450 if Low /= High then
1451 Set_Loop_Actions (Assoc, New_List);
1452 end if;
1454 Nb_Choices := Nb_Choices + 1;
1455 if Box_Present (Assoc) then
1456 Table (Nb_Choices) := (Choice_Lo => Low,
1457 Choice_Hi => High,
1458 Choice_Node => Empty);
1459 else
1460 Table (Nb_Choices) := (Choice_Lo => Low,
1461 Choice_Hi => High,
1462 Choice_Node => Expression (Assoc));
1463 end if;
1464 Next (Choice);
1465 end loop;
1467 Next (Assoc);
1468 end loop;
1470 -- If there is more than one set of choices these must be static
1471 -- and we can therefore sort them. Remember that Nb_Choices does not
1472 -- account for an others choice.
1474 if Nb_Choices > 1 then
1475 Sort_Case_Table (Table);
1476 end if;
1478 -- STEP 1 (b): take care of the whole set of discrete choices
1480 for J in 1 .. Nb_Choices loop
1481 Low := Table (J).Choice_Lo;
1482 High := Table (J).Choice_Hi;
1483 Expr := Table (J).Choice_Node;
1484 Append_List (Gen_Loop (Low, High, Expr), To => New_Code);
1485 end loop;
1487 -- STEP 1 (c): generate the remaining loops to cover others choice
1488 -- We don't need to generate loops over empty gaps, but if there is
1489 -- a single empty range we must analyze the expression for semantics
1491 if Present (Others_Expr) or else Others_Box_Present then
1492 declare
1493 First : Boolean := True;
1495 begin
1496 for J in 0 .. Nb_Choices loop
1497 if J = 0 then
1498 Low := Aggr_Low;
1499 else
1500 Low := Add (1, To => Table (J).Choice_Hi);
1501 end if;
1503 if J = Nb_Choices then
1504 High := Aggr_High;
1505 else
1506 High := Add (-1, To => Table (J + 1).Choice_Lo);
1507 end if;
1509 -- If this is an expansion within an init proc, make
1510 -- sure that discriminant references are replaced by
1511 -- the corresponding discriminal.
1513 if Inside_Init_Proc then
1514 if Is_Entity_Name (Low)
1515 and then Ekind (Entity (Low)) = E_Discriminant
1516 then
1517 Set_Entity (Low, Discriminal (Entity (Low)));
1518 end if;
1520 if Is_Entity_Name (High)
1521 and then Ekind (Entity (High)) = E_Discriminant
1522 then
1523 Set_Entity (High, Discriminal (Entity (High)));
1524 end if;
1525 end if;
1527 if First
1528 or else not Empty_Range (Low, High)
1529 then
1530 First := False;
1531 Append_List
1532 (Gen_Loop (Low, High, Others_Expr), To => New_Code);
1533 end if;
1534 end loop;
1535 end;
1536 end if;
1538 -- STEP 2: Process positional components
1540 else
1541 -- STEP 2 (a): Generate the assignments for each positional element
1542 -- Note that here we have to use Aggr_L rather than Aggr_Low because
1543 -- Aggr_L is analyzed and Add wants an analyzed expression.
1545 Expr := First (Expressions (N));
1546 Nb_Elements := -1;
1548 while Present (Expr) loop
1549 Nb_Elements := Nb_Elements + 1;
1550 Append_List (Gen_Assign (Add (Nb_Elements, To => Aggr_L), Expr),
1551 To => New_Code);
1552 Next (Expr);
1553 end loop;
1555 -- STEP 2 (b): Generate final loop if an others choice is present
1556 -- Here Nb_Elements gives the offset of the last positional element.
1558 if Present (Component_Associations (N)) then
1559 Assoc := Last (Component_Associations (N));
1561 -- Ada 2005 (AI-287)
1563 if Box_Present (Assoc) then
1564 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1565 Aggr_High,
1566 Empty),
1567 To => New_Code);
1568 else
1569 Expr := Expression (Assoc);
1571 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1572 Aggr_High,
1573 Expr), -- AI-287
1574 To => New_Code);
1575 end if;
1576 end if;
1577 end if;
1579 return New_Code;
1580 end Build_Array_Aggr_Code;
1582 ----------------------------
1583 -- Build_Record_Aggr_Code --
1584 ----------------------------
1586 function Build_Record_Aggr_Code
1587 (N : Node_Id;
1588 Typ : Entity_Id;
1589 Target : Node_Id;
1590 Flist : Node_Id := Empty;
1591 Obj : Entity_Id := Empty;
1592 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id
1594 Loc : constant Source_Ptr := Sloc (N);
1595 L : constant List_Id := New_List;
1596 N_Typ : constant Entity_Id := Etype (N);
1598 Comp : Node_Id;
1599 Instr : Node_Id;
1600 Ref : Node_Id;
1601 F : Node_Id;
1602 Comp_Type : Entity_Id;
1603 Selector : Entity_Id;
1604 Comp_Expr : Node_Id;
1605 Expr_Q : Node_Id;
1607 Internal_Final_List : Node_Id;
1609 -- If this is an internal aggregate, the External_Final_List is an
1610 -- expression for the controller record of the enclosing type.
1611 -- If the current aggregate has several controlled components, this
1612 -- expression will appear in several calls to attach to the finali-
1613 -- zation list, and it must not be shared.
1615 External_Final_List : Node_Id;
1616 Ancestor_Is_Expression : Boolean := False;
1617 Ancestor_Is_Subtype_Mark : Boolean := False;
1619 Init_Typ : Entity_Id := Empty;
1620 Attach : Node_Id;
1621 Ctrl_Stuff_Done : Boolean := False;
1623 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id;
1624 -- Returns the value that the given discriminant of an ancestor
1625 -- type should receive (in the absence of a conflict with the
1626 -- value provided by an ancestor part of an extension aggregate).
1628 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id);
1629 -- Check that each of the discriminant values defined by the
1630 -- ancestor part of an extension aggregate match the corresponding
1631 -- values provided by either an association of the aggregate or
1632 -- by the constraint imposed by a parent type (RM95-4.3.2(8)).
1634 function Compatible_Int_Bounds
1635 (Agg_Bounds : Node_Id;
1636 Typ_Bounds : Node_Id) return Boolean;
1637 -- Return true if Agg_Bounds are equal or within Typ_Bounds. It is
1638 -- assumed that both bounds are integer ranges.
1640 procedure Gen_Ctrl_Actions_For_Aggr;
1641 -- Deal with the various controlled type data structure
1642 -- initializations.
1644 function Get_Constraint_Association (T : Entity_Id) return Node_Id;
1645 -- Returns the first discriminant association in the constraint
1646 -- associated with T, if any, otherwise returns Empty.
1648 function Init_Controller
1649 (Target : Node_Id;
1650 Typ : Entity_Id;
1651 F : Node_Id;
1652 Attach : Node_Id;
1653 Init_Pr : Boolean) return List_Id;
1654 -- returns the list of statements necessary to initialize the internal
1655 -- controller of the (possible) ancestor typ into target and attach
1656 -- it to finalization list F. Init_Pr conditions the call to the
1657 -- init proc since it may already be done due to ancestor initialization
1659 function Is_Int_Range_Bounds (Bounds : Node_Id) return Boolean;
1660 -- Check whether Bounds is a range node and its lower and higher bounds
1661 -- are integers literals.
1663 ---------------------------------
1664 -- Ancestor_Discriminant_Value --
1665 ---------------------------------
1667 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id is
1668 Assoc : Node_Id;
1669 Assoc_Elmt : Elmt_Id;
1670 Aggr_Comp : Entity_Id;
1671 Corresp_Disc : Entity_Id;
1672 Current_Typ : Entity_Id := Base_Type (Typ);
1673 Parent_Typ : Entity_Id;
1674 Parent_Disc : Entity_Id;
1675 Save_Assoc : Node_Id := Empty;
1677 begin
1678 -- First check any discriminant associations to see if
1679 -- any of them provide a value for the discriminant.
1681 if Present (Discriminant_Specifications (Parent (Current_Typ))) then
1682 Assoc := First (Component_Associations (N));
1683 while Present (Assoc) loop
1684 Aggr_Comp := Entity (First (Choices (Assoc)));
1686 if Ekind (Aggr_Comp) = E_Discriminant then
1687 Save_Assoc := Expression (Assoc);
1689 Corresp_Disc := Corresponding_Discriminant (Aggr_Comp);
1690 while Present (Corresp_Disc) loop
1691 -- If found a corresponding discriminant then return
1692 -- the value given in the aggregate. (Note: this is
1693 -- not correct in the presence of side effects. ???)
1695 if Disc = Corresp_Disc then
1696 return Duplicate_Subexpr (Expression (Assoc));
1697 end if;
1699 Corresp_Disc :=
1700 Corresponding_Discriminant (Corresp_Disc);
1701 end loop;
1702 end if;
1704 Next (Assoc);
1705 end loop;
1706 end if;
1708 -- No match found in aggregate, so chain up parent types to find
1709 -- a constraint that defines the value of the discriminant.
1711 Parent_Typ := Etype (Current_Typ);
1712 while Current_Typ /= Parent_Typ loop
1713 if Has_Discriminants (Parent_Typ) then
1714 Parent_Disc := First_Discriminant (Parent_Typ);
1716 -- We either get the association from the subtype indication
1717 -- of the type definition itself, or from the discriminant
1718 -- constraint associated with the type entity (which is
1719 -- preferable, but it's not always present ???)
1721 if Is_Empty_Elmt_List (
1722 Discriminant_Constraint (Current_Typ))
1723 then
1724 Assoc := Get_Constraint_Association (Current_Typ);
1725 Assoc_Elmt := No_Elmt;
1726 else
1727 Assoc_Elmt :=
1728 First_Elmt (Discriminant_Constraint (Current_Typ));
1729 Assoc := Node (Assoc_Elmt);
1730 end if;
1732 -- Traverse the discriminants of the parent type looking
1733 -- for one that corresponds.
1735 while Present (Parent_Disc) and then Present (Assoc) loop
1736 Corresp_Disc := Parent_Disc;
1737 while Present (Corresp_Disc)
1738 and then Disc /= Corresp_Disc
1739 loop
1740 Corresp_Disc :=
1741 Corresponding_Discriminant (Corresp_Disc);
1742 end loop;
1744 if Disc = Corresp_Disc then
1745 if Nkind (Assoc) = N_Discriminant_Association then
1746 Assoc := Expression (Assoc);
1747 end if;
1749 -- If the located association directly denotes
1750 -- a discriminant, then use the value of a saved
1751 -- association of the aggregate. This is a kludge
1752 -- to handle certain cases involving multiple
1753 -- discriminants mapped to a single discriminant
1754 -- of a descendant. It's not clear how to locate the
1755 -- appropriate discriminant value for such cases. ???
1757 if Is_Entity_Name (Assoc)
1758 and then Ekind (Entity (Assoc)) = E_Discriminant
1759 then
1760 Assoc := Save_Assoc;
1761 end if;
1763 return Duplicate_Subexpr (Assoc);
1764 end if;
1766 Next_Discriminant (Parent_Disc);
1768 if No (Assoc_Elmt) then
1769 Next (Assoc);
1770 else
1771 Next_Elmt (Assoc_Elmt);
1772 if Present (Assoc_Elmt) then
1773 Assoc := Node (Assoc_Elmt);
1774 else
1775 Assoc := Empty;
1776 end if;
1777 end if;
1778 end loop;
1779 end if;
1781 Current_Typ := Parent_Typ;
1782 Parent_Typ := Etype (Current_Typ);
1783 end loop;
1785 -- In some cases there's no ancestor value to locate (such as
1786 -- when an ancestor part given by an expression defines the
1787 -- discriminant value).
1789 return Empty;
1790 end Ancestor_Discriminant_Value;
1792 ----------------------------------
1793 -- Check_Ancestor_Discriminants --
1794 ----------------------------------
1796 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id) is
1797 Discr : Entity_Id := First_Discriminant (Base_Type (Anc_Typ));
1798 Disc_Value : Node_Id;
1799 Cond : Node_Id;
1801 begin
1802 while Present (Discr) loop
1803 Disc_Value := Ancestor_Discriminant_Value (Discr);
1805 if Present (Disc_Value) then
1806 Cond := Make_Op_Ne (Loc,
1807 Left_Opnd =>
1808 Make_Selected_Component (Loc,
1809 Prefix => New_Copy_Tree (Target),
1810 Selector_Name => New_Occurrence_Of (Discr, Loc)),
1811 Right_Opnd => Disc_Value);
1813 Append_To (L,
1814 Make_Raise_Constraint_Error (Loc,
1815 Condition => Cond,
1816 Reason => CE_Discriminant_Check_Failed));
1817 end if;
1819 Next_Discriminant (Discr);
1820 end loop;
1821 end Check_Ancestor_Discriminants;
1823 ---------------------------
1824 -- Compatible_Int_Bounds --
1825 ---------------------------
1827 function Compatible_Int_Bounds
1828 (Agg_Bounds : Node_Id;
1829 Typ_Bounds : Node_Id) return Boolean
1831 Agg_Lo : constant Uint := Intval (Low_Bound (Agg_Bounds));
1832 Agg_Hi : constant Uint := Intval (High_Bound (Agg_Bounds));
1833 Typ_Lo : constant Uint := Intval (Low_Bound (Typ_Bounds));
1834 Typ_Hi : constant Uint := Intval (High_Bound (Typ_Bounds));
1835 begin
1836 return Typ_Lo <= Agg_Lo and then Agg_Hi <= Typ_Hi;
1837 end Compatible_Int_Bounds;
1839 --------------------------------
1840 -- Get_Constraint_Association --
1841 --------------------------------
1843 function Get_Constraint_Association (T : Entity_Id) return Node_Id is
1844 Typ_Def : constant Node_Id := Type_Definition (Parent (T));
1845 Indic : constant Node_Id := Subtype_Indication (Typ_Def);
1847 begin
1848 -- ??? Also need to cover case of a type mark denoting a subtype
1849 -- with constraint.
1851 if Nkind (Indic) = N_Subtype_Indication
1852 and then Present (Constraint (Indic))
1853 then
1854 return First (Constraints (Constraint (Indic)));
1855 end if;
1857 return Empty;
1858 end Get_Constraint_Association;
1860 ---------------------
1861 -- Init_controller --
1862 ---------------------
1864 function Init_Controller
1865 (Target : Node_Id;
1866 Typ : Entity_Id;
1867 F : Node_Id;
1868 Attach : Node_Id;
1869 Init_Pr : Boolean) return List_Id
1871 L : constant List_Id := New_List;
1872 Ref : Node_Id;
1873 RC : RE_Id;
1875 begin
1876 -- Generate:
1877 -- init-proc (target._controller);
1878 -- initialize (target._controller);
1879 -- Attach_to_Final_List (target._controller, F);
1881 Ref :=
1882 Make_Selected_Component (Loc,
1883 Prefix => Convert_To (Typ, New_Copy_Tree (Target)),
1884 Selector_Name => Make_Identifier (Loc, Name_uController));
1885 Set_Assignment_OK (Ref);
1887 -- Ada 2005 (AI-287): Give support to default initialization of
1888 -- limited types and components.
1890 if (Nkind (Target) = N_Identifier
1891 and then Present (Etype (Target))
1892 and then Is_Limited_Type (Etype (Target)))
1893 or else
1894 (Nkind (Target) = N_Selected_Component
1895 and then Present (Etype (Selector_Name (Target)))
1896 and then Is_Limited_Type (Etype (Selector_Name (Target))))
1897 or else
1898 (Nkind (Target) = N_Unchecked_Type_Conversion
1899 and then Present (Etype (Target))
1900 and then Is_Limited_Type (Etype (Target)))
1901 or else
1902 (Nkind (Target) = N_Unchecked_Expression
1903 and then Nkind (Expression (Target)) = N_Indexed_Component
1904 and then Present (Etype (Prefix (Expression (Target))))
1905 and then Is_Limited_Type (Etype (Prefix (Expression (Target)))))
1906 then
1907 RC := RE_Limited_Record_Controller;
1908 else
1909 RC := RE_Record_Controller;
1910 end if;
1912 if Init_Pr then
1913 Append_List_To (L,
1914 Build_Initialization_Call (Loc,
1915 Id_Ref => Ref,
1916 Typ => RTE (RC),
1917 In_Init_Proc => Within_Init_Proc));
1918 end if;
1920 Append_To (L,
1921 Make_Procedure_Call_Statement (Loc,
1922 Name =>
1923 New_Reference_To (
1924 Find_Prim_Op (RTE (RC), Name_Initialize), Loc),
1925 Parameter_Associations =>
1926 New_List (New_Copy_Tree (Ref))));
1928 Append_To (L,
1929 Make_Attach_Call (
1930 Obj_Ref => New_Copy_Tree (Ref),
1931 Flist_Ref => F,
1932 With_Attach => Attach));
1934 return L;
1935 end Init_Controller;
1937 -------------------------
1938 -- Is_Int_Range_Bounds --
1939 -------------------------
1941 function Is_Int_Range_Bounds (Bounds : Node_Id) return Boolean is
1942 begin
1943 return Nkind (Bounds) = N_Range
1944 and then Nkind (Low_Bound (Bounds)) = N_Integer_Literal
1945 and then Nkind (High_Bound (Bounds)) = N_Integer_Literal;
1946 end Is_Int_Range_Bounds;
1948 -------------------------------
1949 -- Gen_Ctrl_Actions_For_Aggr --
1950 -------------------------------
1952 procedure Gen_Ctrl_Actions_For_Aggr is
1953 begin
1954 if Present (Obj)
1955 and then Finalize_Storage_Only (Typ)
1956 and then (Is_Library_Level_Entity (Obj)
1957 or else Entity (Constant_Value (RTE (RE_Garbage_Collected))) =
1958 Standard_True)
1959 then
1960 Attach := Make_Integer_Literal (Loc, 0);
1962 elsif Nkind (Parent (N)) = N_Qualified_Expression
1963 and then Nkind (Parent (Parent (N))) = N_Allocator
1964 then
1965 Attach := Make_Integer_Literal (Loc, 2);
1967 else
1968 Attach := Make_Integer_Literal (Loc, 1);
1969 end if;
1971 -- Determine the external finalization list. It is either the
1972 -- finalization list of the outer-scope or the one coming from
1973 -- an outer aggregate. When the target is not a temporary, the
1974 -- proper scope is the scope of the target rather than the
1975 -- potentially transient current scope.
1977 if Controlled_Type (Typ) then
1978 if Present (Flist) then
1979 External_Final_List := New_Copy_Tree (Flist);
1981 elsif Is_Entity_Name (Target)
1982 and then Present (Scope (Entity (Target)))
1983 then
1984 External_Final_List
1985 := Find_Final_List (Scope (Entity (Target)));
1987 else
1988 External_Final_List := Find_Final_List (Current_Scope);
1989 end if;
1991 else
1992 External_Final_List := Empty;
1993 end if;
1995 -- Initialize and attach the outer object in the is_controlled case
1997 if Is_Controlled (Typ) then
1998 if Ancestor_Is_Subtype_Mark then
1999 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2000 Set_Assignment_OK (Ref);
2001 Append_To (L,
2002 Make_Procedure_Call_Statement (Loc,
2003 Name =>
2004 New_Reference_To
2005 (Find_Prim_Op (Init_Typ, Name_Initialize), Loc),
2006 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
2007 end if;
2009 if not Has_Controlled_Component (Typ) then
2010 Ref := New_Copy_Tree (Target);
2011 Set_Assignment_OK (Ref);
2012 Append_To (L,
2013 Make_Attach_Call (
2014 Obj_Ref => Ref,
2015 Flist_Ref => New_Copy_Tree (External_Final_List),
2016 With_Attach => Attach));
2017 end if;
2018 end if;
2020 -- In the Has_Controlled component case, all the intermediate
2021 -- controllers must be initialized
2023 if Has_Controlled_Component (Typ)
2024 and not Is_Limited_Ancestor_Expansion
2025 then
2026 declare
2027 Inner_Typ : Entity_Id;
2028 Outer_Typ : Entity_Id;
2029 At_Root : Boolean;
2031 begin
2033 Outer_Typ := Base_Type (Typ);
2035 -- Find outer type with a controller
2037 while Outer_Typ /= Init_Typ
2038 and then not Has_New_Controlled_Component (Outer_Typ)
2039 loop
2040 Outer_Typ := Etype (Outer_Typ);
2041 end loop;
2043 -- Attach it to the outer record controller to the
2044 -- external final list
2046 if Outer_Typ = Init_Typ then
2047 Append_List_To (L,
2048 Init_Controller (
2049 Target => Target,
2050 Typ => Outer_Typ,
2051 F => External_Final_List,
2052 Attach => Attach,
2053 Init_Pr => False));
2055 At_Root := True;
2056 Inner_Typ := Init_Typ;
2058 else
2059 Append_List_To (L,
2060 Init_Controller (
2061 Target => Target,
2062 Typ => Outer_Typ,
2063 F => External_Final_List,
2064 Attach => Attach,
2065 Init_Pr => True));
2067 Inner_Typ := Etype (Outer_Typ);
2068 At_Root :=
2069 not Is_Tagged_Type (Typ) or else Inner_Typ = Outer_Typ;
2070 end if;
2072 -- The outer object has to be attached as well
2074 if Is_Controlled (Typ) then
2075 Ref := New_Copy_Tree (Target);
2076 Set_Assignment_OK (Ref);
2077 Append_To (L,
2078 Make_Attach_Call (
2079 Obj_Ref => Ref,
2080 Flist_Ref => New_Copy_Tree (External_Final_List),
2081 With_Attach => New_Copy_Tree (Attach)));
2082 end if;
2084 -- Initialize the internal controllers for tagged types with
2085 -- more than one controller.
2087 while not At_Root and then Inner_Typ /= Init_Typ loop
2088 if Has_New_Controlled_Component (Inner_Typ) then
2089 F :=
2090 Make_Selected_Component (Loc,
2091 Prefix =>
2092 Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2093 Selector_Name =>
2094 Make_Identifier (Loc, Name_uController));
2095 F :=
2096 Make_Selected_Component (Loc,
2097 Prefix => F,
2098 Selector_Name => Make_Identifier (Loc, Name_F));
2100 Append_List_To (L,
2101 Init_Controller (
2102 Target => Target,
2103 Typ => Inner_Typ,
2104 F => F,
2105 Attach => Make_Integer_Literal (Loc, 1),
2106 Init_Pr => True));
2107 Outer_Typ := Inner_Typ;
2108 end if;
2110 -- Stop at the root
2112 At_Root := Inner_Typ = Etype (Inner_Typ);
2113 Inner_Typ := Etype (Inner_Typ);
2114 end loop;
2116 -- If not done yet attach the controller of the ancestor part
2118 if Outer_Typ /= Init_Typ
2119 and then Inner_Typ = Init_Typ
2120 and then Has_Controlled_Component (Init_Typ)
2121 then
2122 F :=
2123 Make_Selected_Component (Loc,
2124 Prefix => Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2125 Selector_Name =>
2126 Make_Identifier (Loc, Name_uController));
2127 F :=
2128 Make_Selected_Component (Loc,
2129 Prefix => F,
2130 Selector_Name => Make_Identifier (Loc, Name_F));
2132 Attach := Make_Integer_Literal (Loc, 1);
2133 Append_List_To (L,
2134 Init_Controller (
2135 Target => Target,
2136 Typ => Init_Typ,
2137 F => F,
2138 Attach => Attach,
2139 Init_Pr => Ancestor_Is_Expression));
2140 end if;
2141 end;
2142 end if;
2143 end Gen_Ctrl_Actions_For_Aggr;
2145 -- Start of processing for Build_Record_Aggr_Code
2147 begin
2148 -- Deal with the ancestor part of extension aggregates
2149 -- or with the discriminants of the root type
2151 if Nkind (N) = N_Extension_Aggregate then
2152 declare
2153 A : constant Node_Id := Ancestor_Part (N);
2154 Assign : List_Id;
2156 begin
2157 -- If the ancestor part is a subtype mark "T", we generate
2159 -- init-proc (T(tmp)); if T is constrained and
2160 -- init-proc (S(tmp)); where S applies an appropriate
2161 -- constraint if T is unconstrained
2163 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
2164 Ancestor_Is_Subtype_Mark := True;
2166 if Is_Constrained (Entity (A)) then
2167 Init_Typ := Entity (A);
2169 -- For an ancestor part given by an unconstrained type
2170 -- mark, create a subtype constrained by appropriate
2171 -- corresponding discriminant values coming from either
2172 -- associations of the aggregate or a constraint on
2173 -- a parent type. The subtype will be used to generate
2174 -- the correct default value for the ancestor part.
2176 elsif Has_Discriminants (Entity (A)) then
2177 declare
2178 Anc_Typ : constant Entity_Id := Entity (A);
2179 Anc_Constr : constant List_Id := New_List;
2180 Discrim : Entity_Id;
2181 Disc_Value : Node_Id;
2182 New_Indic : Node_Id;
2183 Subt_Decl : Node_Id;
2185 begin
2186 Discrim := First_Discriminant (Anc_Typ);
2187 while Present (Discrim) loop
2188 Disc_Value := Ancestor_Discriminant_Value (Discrim);
2189 Append_To (Anc_Constr, Disc_Value);
2190 Next_Discriminant (Discrim);
2191 end loop;
2193 New_Indic :=
2194 Make_Subtype_Indication (Loc,
2195 Subtype_Mark => New_Occurrence_Of (Anc_Typ, Loc),
2196 Constraint =>
2197 Make_Index_Or_Discriminant_Constraint (Loc,
2198 Constraints => Anc_Constr));
2200 Init_Typ := Create_Itype (Ekind (Anc_Typ), N);
2202 Subt_Decl :=
2203 Make_Subtype_Declaration (Loc,
2204 Defining_Identifier => Init_Typ,
2205 Subtype_Indication => New_Indic);
2207 -- Itypes must be analyzed with checks off
2208 -- Declaration must have a parent for proper
2209 -- handling of subsidiary actions.
2211 Set_Parent (Subt_Decl, N);
2212 Analyze (Subt_Decl, Suppress => All_Checks);
2213 end;
2214 end if;
2216 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2217 Set_Assignment_OK (Ref);
2219 if Has_Default_Init_Comps (N)
2220 or else Has_Task (Base_Type (Init_Typ))
2221 then
2222 Append_List_To (L,
2223 Build_Initialization_Call (Loc,
2224 Id_Ref => Ref,
2225 Typ => Init_Typ,
2226 In_Init_Proc => Within_Init_Proc,
2227 With_Default_Init => True));
2228 else
2229 Append_List_To (L,
2230 Build_Initialization_Call (Loc,
2231 Id_Ref => Ref,
2232 Typ => Init_Typ,
2233 In_Init_Proc => Within_Init_Proc));
2234 end if;
2236 if Is_Constrained (Entity (A))
2237 and then Has_Discriminants (Entity (A))
2238 then
2239 Check_Ancestor_Discriminants (Entity (A));
2240 end if;
2242 -- Ada 2005 (AI-287): If the ancestor part is a limited type,
2243 -- a recursive call expands the ancestor.
2245 elsif Is_Limited_Type (Etype (A)) then
2246 Ancestor_Is_Expression := True;
2248 Append_List_To (L,
2249 Build_Record_Aggr_Code (
2250 N => Expression (A),
2251 Typ => Etype (Expression (A)),
2252 Target => Target,
2253 Flist => Flist,
2254 Obj => Obj,
2255 Is_Limited_Ancestor_Expansion => True));
2257 -- If the ancestor part is an expression "E", we generate
2258 -- T(tmp) := E;
2260 else
2261 Ancestor_Is_Expression := True;
2262 Init_Typ := Etype (A);
2264 -- If the ancestor part is an aggregate, force its full
2265 -- expansion, which was delayed.
2267 if Nkind (A) = N_Qualified_Expression
2268 and then (Nkind (Expression (A)) = N_Aggregate
2269 or else
2270 Nkind (Expression (A)) = N_Extension_Aggregate)
2271 then
2272 Set_Analyzed (A, False);
2273 Set_Analyzed (Expression (A), False);
2274 end if;
2276 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2277 Set_Assignment_OK (Ref);
2279 -- Make the assignment without usual controlled actions since
2280 -- we only want the post adjust but not the pre finalize here
2281 -- Add manual adjust when necessary
2283 Assign := New_List (
2284 Make_OK_Assignment_Statement (Loc,
2285 Name => Ref,
2286 Expression => A));
2287 Set_No_Ctrl_Actions (First (Assign));
2289 -- Assign the tag now to make sure that the dispatching call in
2290 -- the subsequent deep_adjust works properly (unless Java_VM,
2291 -- where tags are implicit).
2293 if not Java_VM then
2294 Instr :=
2295 Make_OK_Assignment_Statement (Loc,
2296 Name =>
2297 Make_Selected_Component (Loc,
2298 Prefix => New_Copy_Tree (Target),
2299 Selector_Name =>
2300 New_Reference_To
2301 (First_Tag_Component (Base_Type (Typ)), Loc)),
2303 Expression =>
2304 Unchecked_Convert_To (RTE (RE_Tag),
2305 New_Reference_To
2306 (Node (First_Elmt
2307 (Access_Disp_Table (Base_Type (Typ)))),
2308 Loc)));
2310 Set_Assignment_OK (Name (Instr));
2311 Append_To (Assign, Instr);
2312 end if;
2314 -- Call Adjust manually
2316 if Controlled_Type (Etype (A)) then
2317 Append_List_To (Assign,
2318 Make_Adjust_Call (
2319 Ref => New_Copy_Tree (Ref),
2320 Typ => Etype (A),
2321 Flist_Ref => New_Reference_To (
2322 RTE (RE_Global_Final_List), Loc),
2323 With_Attach => Make_Integer_Literal (Loc, 0)));
2324 end if;
2326 Append_To (L,
2327 Make_Unsuppress_Block (Loc, Name_Discriminant_Check, Assign));
2329 if Has_Discriminants (Init_Typ) then
2330 Check_Ancestor_Discriminants (Init_Typ);
2331 end if;
2332 end if;
2333 end;
2335 -- Normal case (not an extension aggregate)
2337 else
2338 -- Generate the discriminant expressions, component by component.
2339 -- If the base type is an unchecked union, the discriminants are
2340 -- unknown to the back-end and absent from a value of the type, so
2341 -- assignments for them are not emitted.
2343 if Has_Discriminants (Typ)
2344 and then not Is_Unchecked_Union (Base_Type (Typ))
2345 then
2346 -- If the type is derived, and constrains discriminants of the
2347 -- parent type, these discriminants are not components of the
2348 -- aggregate, and must be initialized explicitly. They are not
2349 -- visible components of the object, but can become visible with
2350 -- a view conversion to the ancestor.
2352 declare
2353 Btype : Entity_Id;
2354 Parent_Type : Entity_Id;
2355 Disc : Entity_Id;
2356 Discr_Val : Elmt_Id;
2358 begin
2359 Btype := Base_Type (Typ);
2361 while Is_Derived_Type (Btype)
2362 and then Present (Stored_Constraint (Btype))
2363 loop
2364 Parent_Type := Etype (Btype);
2366 Disc := First_Discriminant (Parent_Type);
2367 Discr_Val :=
2368 First_Elmt (Stored_Constraint (Base_Type (Typ)));
2369 while Present (Discr_Val) loop
2371 -- Only those discriminants of the parent that are not
2372 -- renamed by discriminants of the derived type need to
2373 -- be added explicitly.
2375 if not Is_Entity_Name (Node (Discr_Val))
2376 or else
2377 Ekind (Entity (Node (Discr_Val))) /= E_Discriminant
2378 then
2379 Comp_Expr :=
2380 Make_Selected_Component (Loc,
2381 Prefix => New_Copy_Tree (Target),
2382 Selector_Name => New_Occurrence_Of (Disc, Loc));
2384 Instr :=
2385 Make_OK_Assignment_Statement (Loc,
2386 Name => Comp_Expr,
2387 Expression => New_Copy_Tree (Node (Discr_Val)));
2389 Set_No_Ctrl_Actions (Instr);
2390 Append_To (L, Instr);
2391 end if;
2393 Next_Discriminant (Disc);
2394 Next_Elmt (Discr_Val);
2395 end loop;
2397 Btype := Base_Type (Parent_Type);
2398 end loop;
2399 end;
2401 -- Generate discriminant init values for the visible discriminants
2403 declare
2404 Discriminant : Entity_Id;
2405 Discriminant_Value : Node_Id;
2407 begin
2408 Discriminant := First_Stored_Discriminant (Typ);
2410 while Present (Discriminant) loop
2412 Comp_Expr :=
2413 Make_Selected_Component (Loc,
2414 Prefix => New_Copy_Tree (Target),
2415 Selector_Name => New_Occurrence_Of (Discriminant, Loc));
2417 Discriminant_Value :=
2418 Get_Discriminant_Value (
2419 Discriminant,
2420 N_Typ,
2421 Discriminant_Constraint (N_Typ));
2423 Instr :=
2424 Make_OK_Assignment_Statement (Loc,
2425 Name => Comp_Expr,
2426 Expression => New_Copy_Tree (Discriminant_Value));
2428 Set_No_Ctrl_Actions (Instr);
2429 Append_To (L, Instr);
2431 Next_Stored_Discriminant (Discriminant);
2432 end loop;
2433 end;
2434 end if;
2435 end if;
2437 -- Generate the assignments, component by component
2439 -- tmp.comp1 := Expr1_From_Aggr;
2440 -- tmp.comp2 := Expr2_From_Aggr;
2441 -- ....
2443 Comp := First (Component_Associations (N));
2444 while Present (Comp) loop
2445 Selector := Entity (First (Choices (Comp)));
2447 -- Ada 2005 (AI-287): For each default-initialized component genarate
2448 -- a call to the corresponding IP subprogram if available.
2450 if Box_Present (Comp)
2451 and then Has_Non_Null_Base_Init_Proc (Etype (Selector))
2452 then
2453 -- Ada 2005 (AI-287): If the component type has tasks then
2454 -- generate the activation chain and master entities (except
2455 -- in case of an allocator because in that case these entities
2456 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
2458 declare
2459 Ctype : constant Entity_Id := Etype (Selector);
2460 Inside_Allocator : Boolean := False;
2461 P : Node_Id := Parent (N);
2463 begin
2464 if Is_Task_Type (Ctype) or else Has_Task (Ctype) then
2465 while Present (P) loop
2466 if Nkind (P) = N_Allocator then
2467 Inside_Allocator := True;
2468 exit;
2469 end if;
2471 P := Parent (P);
2472 end loop;
2474 if not Inside_Init_Proc and not Inside_Allocator then
2475 Build_Activation_Chain_Entity (N);
2476 end if;
2477 end if;
2478 end;
2480 Append_List_To (L,
2481 Build_Initialization_Call (Loc,
2482 Id_Ref => Make_Selected_Component (Loc,
2483 Prefix => New_Copy_Tree (Target),
2484 Selector_Name => New_Occurrence_Of (Selector,
2485 Loc)),
2486 Typ => Etype (Selector),
2487 With_Default_Init => True));
2489 goto Next_Comp;
2490 end if;
2492 -- Prepare for component assignment
2494 if Ekind (Selector) /= E_Discriminant
2495 or else Nkind (N) = N_Extension_Aggregate
2496 then
2498 -- All the discriminants have now been assigned
2499 -- This is now a good moment to initialize and attach all the
2500 -- controllers. Their position may depend on the discriminants.
2502 if Ekind (Selector) /= E_Discriminant
2503 and then not Ctrl_Stuff_Done
2504 then
2505 Gen_Ctrl_Actions_For_Aggr;
2506 Ctrl_Stuff_Done := True;
2507 end if;
2509 Comp_Type := Etype (Selector);
2510 Comp_Expr :=
2511 Make_Selected_Component (Loc,
2512 Prefix => New_Copy_Tree (Target),
2513 Selector_Name => New_Occurrence_Of (Selector, Loc));
2515 if Nkind (Expression (Comp)) = N_Qualified_Expression then
2516 Expr_Q := Expression (Expression (Comp));
2517 else
2518 Expr_Q := Expression (Comp);
2519 end if;
2521 -- The controller is the one of the parent type defining
2522 -- the component (in case of inherited components).
2524 if Controlled_Type (Comp_Type) then
2525 Internal_Final_List :=
2526 Make_Selected_Component (Loc,
2527 Prefix => Convert_To (
2528 Scope (Original_Record_Component (Selector)),
2529 New_Copy_Tree (Target)),
2530 Selector_Name =>
2531 Make_Identifier (Loc, Name_uController));
2533 Internal_Final_List :=
2534 Make_Selected_Component (Loc,
2535 Prefix => Internal_Final_List,
2536 Selector_Name => Make_Identifier (Loc, Name_F));
2538 -- The internal final list can be part of a constant object
2540 Set_Assignment_OK (Internal_Final_List);
2542 else
2543 Internal_Final_List := Empty;
2544 end if;
2546 -- Now either create the assignment or generate the code for the
2547 -- inner aggregate top-down.
2549 if Is_Delayed_Aggregate (Expr_Q) then
2551 -- We have the following case of aggregate nesting inside
2552 -- an object declaration:
2554 -- type Arr_Typ is array (Integer range <>) of ...;
2556 -- type Rec_Typ (...) is record
2557 -- Obj_Arr_Typ : Arr_Typ (A .. B);
2558 -- end record;
2560 -- Obj_Rec_Typ : Rec_Typ := (...,
2561 -- Obj_Arr_Typ => (X => (...), Y => (...)));
2563 -- The length of the ranges of the aggregate and Obj_Add_Typ
2564 -- are equal (B - A = Y - X), but they do not coincide (X /=
2565 -- A and B /= Y). This case requires array sliding which is
2566 -- performed in the following manner:
2568 -- subtype Arr_Sub is Arr_Typ (X .. Y);
2569 -- Temp : Arr_Sub;
2570 -- Temp (X) := (...);
2571 -- ...
2572 -- Temp (Y) := (...);
2573 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
2575 if Present (Obj)
2576 and then Ekind (Comp_Type) = E_Array_Subtype
2577 and then Is_Int_Range_Bounds (Aggregate_Bounds (Expr_Q))
2578 and then Is_Int_Range_Bounds (First_Index (Comp_Type))
2579 and then not
2580 Compatible_Int_Bounds (
2581 Agg_Bounds => Aggregate_Bounds (Expr_Q),
2582 Typ_Bounds => First_Index (Comp_Type))
2583 then
2584 declare
2585 -- Create the array subtype with bounds equal to those
2586 -- of the corresponding aggregate.
2588 SubE : constant Entity_Id :=
2589 Make_Defining_Identifier (Loc,
2590 New_Internal_Name ('T'));
2592 SubD : constant Node_Id :=
2593 Make_Subtype_Declaration (Loc,
2594 Defining_Identifier =>
2595 SubE,
2596 Subtype_Indication =>
2597 Make_Subtype_Indication (Loc,
2598 Subtype_Mark => New_Reference_To (
2599 Etype (Comp_Type), Loc),
2600 Constraint =>
2601 Make_Index_Or_Discriminant_Constraint (
2602 Loc, Constraints => New_List (
2603 New_Copy_Tree (Aggregate_Bounds (
2604 Expr_Q))))));
2606 -- Create a temporary array of the above subtype which
2607 -- will be used to capture the aggregate assignments.
2609 TmpE : constant Entity_Id :=
2610 Make_Defining_Identifier (Loc,
2611 New_Internal_Name ('A'));
2613 TmpD : constant Node_Id :=
2614 Make_Object_Declaration (Loc,
2615 Defining_Identifier =>
2616 TmpE,
2617 Object_Definition =>
2618 New_Reference_To (SubE, Loc));
2620 begin
2621 Set_No_Initialization (TmpD);
2622 Append_To (L, SubD);
2623 Append_To (L, TmpD);
2625 -- Expand the aggregate into assignments to the temporary
2626 -- array.
2628 Append_List_To (L,
2629 Late_Expansion (Expr_Q, Comp_Type,
2630 New_Reference_To (TmpE, Loc), Internal_Final_List));
2632 -- Slide
2634 Append_To (L,
2635 Make_Assignment_Statement (Loc,
2636 Name => New_Copy_Tree (Comp_Expr),
2637 Expression => New_Reference_To (TmpE, Loc)));
2639 -- Do not pass the original aggregate to Gigi as is
2640 -- since it will potentially clobber the front or the
2641 -- end of the array. Setting the expression to empty
2642 -- is safe since all aggregates will be expanded into
2643 -- assignments.
2645 Set_Expression (Parent (Obj), Empty);
2646 end;
2648 -- Normal case (sliding not required)
2650 else
2651 Append_List_To (L,
2652 Late_Expansion (Expr_Q, Comp_Type, Comp_Expr,
2653 Internal_Final_List));
2654 end if;
2656 else
2657 Instr :=
2658 Make_OK_Assignment_Statement (Loc,
2659 Name => Comp_Expr,
2660 Expression => Expression (Comp));
2662 Set_No_Ctrl_Actions (Instr);
2663 Append_To (L, Instr);
2665 -- Adjust the tag if tagged (because of possible view
2666 -- conversions), unless compiling for the Java VM
2667 -- where tags are implicit.
2669 -- tmp.comp._tag := comp_typ'tag;
2671 if Is_Tagged_Type (Comp_Type) and then not Java_VM then
2672 Instr :=
2673 Make_OK_Assignment_Statement (Loc,
2674 Name =>
2675 Make_Selected_Component (Loc,
2676 Prefix => New_Copy_Tree (Comp_Expr),
2677 Selector_Name =>
2678 New_Reference_To
2679 (First_Tag_Component (Comp_Type), Loc)),
2681 Expression =>
2682 Unchecked_Convert_To (RTE (RE_Tag),
2683 New_Reference_To
2684 (Node (First_Elmt (Access_Disp_Table (Comp_Type))),
2685 Loc)));
2687 Append_To (L, Instr);
2688 end if;
2690 -- Adjust and Attach the component to the proper controller
2691 -- Adjust (tmp.comp);
2692 -- Attach_To_Final_List (tmp.comp,
2693 -- comp_typ (tmp)._record_controller.f)
2695 if Controlled_Type (Comp_Type) then
2696 Append_List_To (L,
2697 Make_Adjust_Call (
2698 Ref => New_Copy_Tree (Comp_Expr),
2699 Typ => Comp_Type,
2700 Flist_Ref => Internal_Final_List,
2701 With_Attach => Make_Integer_Literal (Loc, 1)));
2702 end if;
2703 end if;
2705 -- ???
2707 elsif Ekind (Selector) = E_Discriminant
2708 and then Nkind (N) /= N_Extension_Aggregate
2709 and then Nkind (Parent (N)) = N_Component_Association
2710 and then Is_Constrained (Typ)
2711 then
2712 -- We must check that the discriminant value imposed by the
2713 -- context is the same as the value given in the subaggregate,
2714 -- because after the expansion into assignments there is no
2715 -- record on which to perform a regular discriminant check.
2717 declare
2718 D_Val : Elmt_Id;
2719 Disc : Entity_Id;
2721 begin
2722 D_Val := First_Elmt (Discriminant_Constraint (Typ));
2723 Disc := First_Discriminant (Typ);
2725 while Chars (Disc) /= Chars (Selector) loop
2726 Next_Discriminant (Disc);
2727 Next_Elmt (D_Val);
2728 end loop;
2730 pragma Assert (Present (D_Val));
2732 Append_To (L,
2733 Make_Raise_Constraint_Error (Loc,
2734 Condition =>
2735 Make_Op_Ne (Loc,
2736 Left_Opnd => New_Copy_Tree (Node (D_Val)),
2737 Right_Opnd => Expression (Comp)),
2738 Reason => CE_Discriminant_Check_Failed));
2739 end;
2740 end if;
2742 <<Next_Comp>>
2744 Next (Comp);
2745 end loop;
2747 -- If the type is tagged, the tag needs to be initialized (unless
2748 -- compiling for the Java VM where tags are implicit). It is done
2749 -- late in the initialization process because in some cases, we call
2750 -- the init proc of an ancestor which will not leave out the right tag
2752 if Ancestor_Is_Expression then
2753 null;
2755 elsif Is_Tagged_Type (Typ) and then not Java_VM then
2756 Instr :=
2757 Make_OK_Assignment_Statement (Loc,
2758 Name =>
2759 Make_Selected_Component (Loc,
2760 Prefix => New_Copy_Tree (Target),
2761 Selector_Name =>
2762 New_Reference_To
2763 (First_Tag_Component (Base_Type (Typ)), Loc)),
2765 Expression =>
2766 Unchecked_Convert_To (RTE (RE_Tag),
2767 New_Reference_To
2768 (Node (First_Elmt (Access_Disp_Table (Base_Type (Typ)))),
2769 Loc)));
2771 Append_To (L, Instr);
2772 end if;
2774 -- If the controllers have not been initialized yet (by lack of non-
2775 -- discriminant components), let's do it now.
2777 if not Ctrl_Stuff_Done then
2778 Gen_Ctrl_Actions_For_Aggr;
2779 Ctrl_Stuff_Done := True;
2780 end if;
2782 return L;
2783 end Build_Record_Aggr_Code;
2785 -------------------------------
2786 -- Convert_Aggr_In_Allocator --
2787 -------------------------------
2789 procedure Convert_Aggr_In_Allocator (Decl, Aggr : Node_Id) is
2790 Loc : constant Source_Ptr := Sloc (Aggr);
2791 Typ : constant Entity_Id := Etype (Aggr);
2792 Temp : constant Entity_Id := Defining_Identifier (Decl);
2794 Occ : constant Node_Id :=
2795 Unchecked_Convert_To (Typ,
2796 Make_Explicit_Dereference (Loc,
2797 New_Reference_To (Temp, Loc)));
2799 Access_Type : constant Entity_Id := Etype (Temp);
2801 begin
2802 if Is_Array_Type (Typ) then
2803 Convert_Array_Aggr_In_Allocator (Decl, Aggr, Occ);
2805 elsif Has_Default_Init_Comps (Aggr) then
2806 declare
2807 L : constant List_Id := New_List;
2808 Init_Stmts : List_Id;
2810 begin
2811 Init_Stmts := Late_Expansion (Aggr, Typ, Occ,
2812 Find_Final_List (Access_Type),
2813 Associated_Final_Chain (Base_Type (Access_Type)));
2815 Build_Task_Allocate_Block_With_Init_Stmts (L, Aggr, Init_Stmts);
2816 Insert_Actions_After (Decl, L);
2817 end;
2819 else
2820 Insert_Actions_After (Decl,
2821 Late_Expansion (Aggr, Typ, Occ,
2822 Find_Final_List (Access_Type),
2823 Associated_Final_Chain (Base_Type (Access_Type))));
2824 end if;
2825 end Convert_Aggr_In_Allocator;
2827 --------------------------------
2828 -- Convert_Aggr_In_Assignment --
2829 --------------------------------
2831 procedure Convert_Aggr_In_Assignment (N : Node_Id) is
2832 Aggr : Node_Id := Expression (N);
2833 Typ : constant Entity_Id := Etype (Aggr);
2834 Occ : constant Node_Id := New_Copy_Tree (Name (N));
2836 begin
2837 if Nkind (Aggr) = N_Qualified_Expression then
2838 Aggr := Expression (Aggr);
2839 end if;
2841 Insert_Actions_After (N,
2842 Late_Expansion (Aggr, Typ, Occ,
2843 Find_Final_List (Typ, New_Copy_Tree (Occ))));
2844 end Convert_Aggr_In_Assignment;
2846 ---------------------------------
2847 -- Convert_Aggr_In_Object_Decl --
2848 ---------------------------------
2850 procedure Convert_Aggr_In_Object_Decl (N : Node_Id) is
2851 Obj : constant Entity_Id := Defining_Identifier (N);
2852 Aggr : Node_Id := Expression (N);
2853 Loc : constant Source_Ptr := Sloc (Aggr);
2854 Typ : constant Entity_Id := Etype (Aggr);
2855 Occ : constant Node_Id := New_Occurrence_Of (Obj, Loc);
2857 function Discriminants_Ok return Boolean;
2858 -- If the object type is constrained, the discriminants in the
2859 -- aggregate must be checked against the discriminants of the subtype.
2860 -- This cannot be done using Apply_Discriminant_Checks because after
2861 -- expansion there is no aggregate left to check.
2863 ----------------------
2864 -- Discriminants_Ok --
2865 ----------------------
2867 function Discriminants_Ok return Boolean is
2868 Cond : Node_Id := Empty;
2869 Check : Node_Id;
2870 D : Entity_Id;
2871 Disc1 : Elmt_Id;
2872 Disc2 : Elmt_Id;
2873 Val1 : Node_Id;
2874 Val2 : Node_Id;
2876 begin
2877 D := First_Discriminant (Typ);
2878 Disc1 := First_Elmt (Discriminant_Constraint (Typ));
2879 Disc2 := First_Elmt (Discriminant_Constraint (Etype (Obj)));
2881 while Present (Disc1) and then Present (Disc2) loop
2882 Val1 := Node (Disc1);
2883 Val2 := Node (Disc2);
2885 if not Is_OK_Static_Expression (Val1)
2886 or else not Is_OK_Static_Expression (Val2)
2887 then
2888 Check := Make_Op_Ne (Loc,
2889 Left_Opnd => Duplicate_Subexpr (Val1),
2890 Right_Opnd => Duplicate_Subexpr (Val2));
2892 if No (Cond) then
2893 Cond := Check;
2895 else
2896 Cond := Make_Or_Else (Loc,
2897 Left_Opnd => Cond,
2898 Right_Opnd => Check);
2899 end if;
2901 elsif Expr_Value (Val1) /= Expr_Value (Val2) then
2902 Apply_Compile_Time_Constraint_Error (Aggr,
2903 Msg => "incorrect value for discriminant&?",
2904 Reason => CE_Discriminant_Check_Failed,
2905 Ent => D);
2906 return False;
2907 end if;
2909 Next_Discriminant (D);
2910 Next_Elmt (Disc1);
2911 Next_Elmt (Disc2);
2912 end loop;
2914 -- If any discriminant constraint is non-static, emit a check
2916 if Present (Cond) then
2917 Insert_Action (N,
2918 Make_Raise_Constraint_Error (Loc,
2919 Condition => Cond,
2920 Reason => CE_Discriminant_Check_Failed));
2921 end if;
2923 return True;
2924 end Discriminants_Ok;
2926 -- Start of processing for Convert_Aggr_In_Object_Decl
2928 begin
2929 Set_Assignment_OK (Occ);
2931 if Nkind (Aggr) = N_Qualified_Expression then
2932 Aggr := Expression (Aggr);
2933 end if;
2935 if Has_Discriminants (Typ)
2936 and then Typ /= Etype (Obj)
2937 and then Is_Constrained (Etype (Obj))
2938 and then not Discriminants_Ok
2939 then
2940 return;
2941 end if;
2943 if Requires_Transient_Scope (Typ) then
2944 Establish_Transient_Scope (Aggr, Sec_Stack =>
2945 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
2946 end if;
2948 Insert_Actions_After (N, Late_Expansion (Aggr, Typ, Occ, Obj => Obj));
2949 Set_No_Initialization (N);
2950 Initialize_Discriminants (N, Typ);
2951 end Convert_Aggr_In_Object_Decl;
2953 -------------------------------------
2954 -- Convert_array_Aggr_In_Allocator --
2955 -------------------------------------
2957 procedure Convert_Array_Aggr_In_Allocator
2958 (Decl : Node_Id;
2959 Aggr : Node_Id;
2960 Target : Node_Id)
2962 Aggr_Code : List_Id;
2963 Typ : constant Entity_Id := Etype (Aggr);
2964 Ctyp : constant Entity_Id := Component_Type (Typ);
2966 begin
2967 -- The target is an explicit dereference of the allocated object.
2968 -- Generate component assignments to it, as for an aggregate that
2969 -- appears on the right-hand side of an assignment statement.
2971 Aggr_Code :=
2972 Build_Array_Aggr_Code (Aggr,
2973 Ctype => Ctyp,
2974 Index => First_Index (Typ),
2975 Into => Target,
2976 Scalar_Comp => Is_Scalar_Type (Ctyp));
2978 Insert_Actions_After (Decl, Aggr_Code);
2979 end Convert_Array_Aggr_In_Allocator;
2981 ----------------------------
2982 -- Convert_To_Assignments --
2983 ----------------------------
2985 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id) is
2986 Loc : constant Source_Ptr := Sloc (N);
2987 Temp : Entity_Id;
2989 Instr : Node_Id;
2990 Target_Expr : Node_Id;
2991 Parent_Kind : Node_Kind;
2992 Unc_Decl : Boolean := False;
2993 Parent_Node : Node_Id;
2995 begin
2996 Parent_Node := Parent (N);
2997 Parent_Kind := Nkind (Parent_Node);
2999 if Parent_Kind = N_Qualified_Expression then
3001 -- Check if we are in a unconstrained declaration because in this
3002 -- case the current delayed expansion mechanism doesn't work when
3003 -- the declared object size depend on the initializing expr.
3005 begin
3006 Parent_Node := Parent (Parent_Node);
3007 Parent_Kind := Nkind (Parent_Node);
3009 if Parent_Kind = N_Object_Declaration then
3010 Unc_Decl :=
3011 not Is_Entity_Name (Object_Definition (Parent_Node))
3012 or else Has_Discriminants
3013 (Entity (Object_Definition (Parent_Node)))
3014 or else Is_Class_Wide_Type
3015 (Entity (Object_Definition (Parent_Node)));
3016 end if;
3017 end;
3018 end if;
3020 -- Just set the Delay flag in the following cases where the
3021 -- transformation will be done top down from above
3023 -- - internal aggregate (transformed when expanding the parent)
3024 -- - allocators (see Convert_Aggr_In_Allocator)
3025 -- - object decl (see Convert_Aggr_In_Object_Decl)
3026 -- - safe assignments (see Convert_Aggr_Assignments)
3027 -- so far only the assignments in the init procs are taken
3028 -- into account
3030 if Parent_Kind = N_Aggregate
3031 or else Parent_Kind = N_Extension_Aggregate
3032 or else Parent_Kind = N_Component_Association
3033 or else Parent_Kind = N_Allocator
3034 or else (Parent_Kind = N_Object_Declaration and then not Unc_Decl)
3035 or else (Parent_Kind = N_Assignment_Statement
3036 and then Inside_Init_Proc)
3037 then
3038 Set_Expansion_Delayed (N);
3039 return;
3040 end if;
3042 if Requires_Transient_Scope (Typ) then
3043 Establish_Transient_Scope (N, Sec_Stack =>
3044 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
3045 end if;
3047 -- Create the temporary
3049 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
3051 Instr :=
3052 Make_Object_Declaration (Loc,
3053 Defining_Identifier => Temp,
3054 Object_Definition => New_Occurrence_Of (Typ, Loc));
3056 Set_No_Initialization (Instr);
3057 Insert_Action (N, Instr);
3058 Initialize_Discriminants (Instr, Typ);
3059 Target_Expr := New_Occurrence_Of (Temp, Loc);
3061 Insert_Actions (N, Build_Record_Aggr_Code (N, Typ, Target_Expr));
3062 Rewrite (N, New_Occurrence_Of (Temp, Loc));
3063 Analyze_And_Resolve (N, Typ);
3064 end Convert_To_Assignments;
3066 ---------------------------
3067 -- Convert_To_Positional --
3068 ---------------------------
3070 procedure Convert_To_Positional
3071 (N : Node_Id;
3072 Max_Others_Replicate : Nat := 5;
3073 Handle_Bit_Packed : Boolean := False)
3075 Typ : constant Entity_Id := Etype (N);
3077 function Flatten
3078 (N : Node_Id;
3079 Ix : Node_Id;
3080 Ixb : Node_Id) return Boolean;
3081 -- Convert the aggregate into a purely positional form if possible.
3082 -- On entry the bounds of all dimensions are known to be static,
3083 -- and the total number of components is safe enough to expand.
3085 function Is_Flat (N : Node_Id; Dims : Int) return Boolean;
3086 -- Return True iff the array N is flat (which is not rivial
3087 -- in the case of multidimensionsl aggregates).
3089 -------------
3090 -- Flatten --
3091 -------------
3093 function Flatten
3094 (N : Node_Id;
3095 Ix : Node_Id;
3096 Ixb : Node_Id) return Boolean
3098 Loc : constant Source_Ptr := Sloc (N);
3099 Blo : constant Node_Id := Type_Low_Bound (Etype (Ixb));
3100 Lo : constant Node_Id := Type_Low_Bound (Etype (Ix));
3101 Hi : constant Node_Id := Type_High_Bound (Etype (Ix));
3102 Lov : Uint;
3103 Hiv : Uint;
3105 begin
3106 if Nkind (Original_Node (N)) = N_String_Literal then
3107 return True;
3108 end if;
3110 -- Only handle bounds starting at the base type low bound
3111 -- for now since the compiler isn't able to handle different low
3112 -- bounds yet. Case such as new String'(3..5 => ' ') will get
3113 -- the wrong bounds, though it seems that the aggregate should
3114 -- retain the bounds set on its Etype (see C64103E and CC1311B).
3116 Lov := Expr_Value (Lo);
3117 Hiv := Expr_Value (Hi);
3119 if Hiv < Lov
3120 or else not Compile_Time_Known_Value (Blo)
3121 or else (Lov /= Expr_Value (Blo))
3122 then
3123 return False;
3124 end if;
3126 -- Determine if set of alternatives is suitable for conversion
3127 -- and build an array containing the values in sequence.
3129 declare
3130 Vals : array (UI_To_Int (Lov) .. UI_To_Int (Hiv))
3131 of Node_Id := (others => Empty);
3132 -- The values in the aggregate sorted appropriately
3134 Vlist : List_Id;
3135 -- Same data as Vals in list form
3137 Rep_Count : Nat;
3138 -- Used to validate Max_Others_Replicate limit
3140 Elmt : Node_Id;
3141 Num : Int := UI_To_Int (Lov);
3142 Choice : Node_Id;
3143 Lo, Hi : Node_Id;
3145 begin
3146 if Present (Expressions (N)) then
3147 Elmt := First (Expressions (N));
3149 while Present (Elmt) loop
3150 if Nkind (Elmt) = N_Aggregate
3151 and then Present (Next_Index (Ix))
3152 and then
3153 not Flatten (Elmt, Next_Index (Ix), Next_Index (Ixb))
3154 then
3155 return False;
3156 end if;
3158 Vals (Num) := Relocate_Node (Elmt);
3159 Num := Num + 1;
3161 Next (Elmt);
3162 end loop;
3163 end if;
3165 if No (Component_Associations (N)) then
3166 return True;
3167 end if;
3169 Elmt := First (Component_Associations (N));
3171 if Nkind (Expression (Elmt)) = N_Aggregate then
3172 if Present (Next_Index (Ix))
3173 and then
3174 not Flatten
3175 (Expression (Elmt), Next_Index (Ix), Next_Index (Ixb))
3176 then
3177 return False;
3178 end if;
3179 end if;
3181 Component_Loop : while Present (Elmt) loop
3182 Choice := First (Choices (Elmt));
3183 Choice_Loop : while Present (Choice) loop
3185 -- If we have an others choice, fill in the missing elements
3186 -- subject to the limit established by Max_Others_Replicate.
3188 if Nkind (Choice) = N_Others_Choice then
3189 Rep_Count := 0;
3191 for J in Vals'Range loop
3192 if No (Vals (J)) then
3193 Vals (J) := New_Copy_Tree (Expression (Elmt));
3194 Rep_Count := Rep_Count + 1;
3196 -- Check for maximum others replication. Note that
3197 -- we skip this test if either of the restrictions
3198 -- No_Elaboration_Code or No_Implicit_Loops is
3199 -- active, or if this is a preelaborable unit.
3201 declare
3202 P : constant Entity_Id :=
3203 Cunit_Entity (Current_Sem_Unit);
3205 begin
3206 if Restriction_Active (No_Elaboration_Code)
3207 or else Restriction_Active (No_Implicit_Loops)
3208 or else Is_Preelaborated (P)
3209 or else (Ekind (P) = E_Package_Body
3210 and then
3211 Is_Preelaborated (Spec_Entity (P)))
3212 then
3213 null;
3215 elsif Rep_Count > Max_Others_Replicate then
3216 return False;
3217 end if;
3218 end;
3219 end if;
3220 end loop;
3222 exit Component_Loop;
3224 -- Case of a subtype mark
3226 elsif Nkind (Choice) = N_Identifier
3227 and then Is_Type (Entity (Choice))
3228 then
3229 Lo := Type_Low_Bound (Etype (Choice));
3230 Hi := Type_High_Bound (Etype (Choice));
3232 -- Case of subtype indication
3234 elsif Nkind (Choice) = N_Subtype_Indication then
3235 Lo := Low_Bound (Range_Expression (Constraint (Choice)));
3236 Hi := High_Bound (Range_Expression (Constraint (Choice)));
3238 -- Case of a range
3240 elsif Nkind (Choice) = N_Range then
3241 Lo := Low_Bound (Choice);
3242 Hi := High_Bound (Choice);
3244 -- Normal subexpression case
3246 else pragma Assert (Nkind (Choice) in N_Subexpr);
3247 if not Compile_Time_Known_Value (Choice) then
3248 return False;
3250 else
3251 Vals (UI_To_Int (Expr_Value (Choice))) :=
3252 New_Copy_Tree (Expression (Elmt));
3253 goto Continue;
3254 end if;
3255 end if;
3257 -- Range cases merge with Lo,Hi said
3259 if not Compile_Time_Known_Value (Lo)
3260 or else
3261 not Compile_Time_Known_Value (Hi)
3262 then
3263 return False;
3264 else
3265 for J in UI_To_Int (Expr_Value (Lo)) ..
3266 UI_To_Int (Expr_Value (Hi))
3267 loop
3268 Vals (J) := New_Copy_Tree (Expression (Elmt));
3269 end loop;
3270 end if;
3272 <<Continue>>
3273 Next (Choice);
3274 end loop Choice_Loop;
3276 Next (Elmt);
3277 end loop Component_Loop;
3279 -- If we get here the conversion is possible
3281 Vlist := New_List;
3282 for J in Vals'Range loop
3283 Append (Vals (J), Vlist);
3284 end loop;
3286 Rewrite (N, Make_Aggregate (Loc, Expressions => Vlist));
3287 Set_Aggregate_Bounds (N, Aggregate_Bounds (Original_Node (N)));
3288 return True;
3289 end;
3290 end Flatten;
3292 -------------
3293 -- Is_Flat --
3294 -------------
3296 function Is_Flat (N : Node_Id; Dims : Int) return Boolean is
3297 Elmt : Node_Id;
3299 begin
3300 if Dims = 0 then
3301 return True;
3303 elsif Nkind (N) = N_Aggregate then
3304 if Present (Component_Associations (N)) then
3305 return False;
3307 else
3308 Elmt := First (Expressions (N));
3310 while Present (Elmt) loop
3311 if not Is_Flat (Elmt, Dims - 1) then
3312 return False;
3313 end if;
3315 Next (Elmt);
3316 end loop;
3318 return True;
3319 end if;
3320 else
3321 return True;
3322 end if;
3323 end Is_Flat;
3325 -- Start of processing for Convert_To_Positional
3327 begin
3328 -- Ada 2005 (AI-287): Do not convert in case of default initialized
3329 -- components because in this case will need to call the corresponding
3330 -- IP procedure.
3332 if Has_Default_Init_Comps (N) then
3333 return;
3334 end if;
3336 if Is_Flat (N, Number_Dimensions (Typ)) then
3337 return;
3338 end if;
3340 if Is_Bit_Packed_Array (Typ)
3341 and then not Handle_Bit_Packed
3342 then
3343 return;
3344 end if;
3346 -- Do not convert to positional if controlled components are
3347 -- involved since these require special processing
3349 if Has_Controlled_Component (Typ) then
3350 return;
3351 end if;
3353 if Aggr_Size_OK (Typ)
3354 and then
3355 Flatten (N, First_Index (Typ), First_Index (Base_Type (Typ)))
3356 then
3357 Analyze_And_Resolve (N, Typ);
3358 end if;
3359 end Convert_To_Positional;
3361 ----------------------------
3362 -- Expand_Array_Aggregate --
3363 ----------------------------
3365 -- Array aggregate expansion proceeds as follows:
3367 -- 1. If requested we generate code to perform all the array aggregate
3368 -- bound checks, specifically
3370 -- (a) Check that the index range defined by aggregate bounds is
3371 -- compatible with corresponding index subtype.
3373 -- (b) If an others choice is present check that no aggregate
3374 -- index is outside the bounds of the index constraint.
3376 -- (c) For multidimensional arrays make sure that all subaggregates
3377 -- corresponding to the same dimension have the same bounds.
3379 -- 2. Check for packed array aggregate which can be converted to a
3380 -- constant so that the aggregate disappeares completely.
3382 -- 3. Check case of nested aggregate. Generally nested aggregates are
3383 -- handled during the processing of the parent aggregate.
3385 -- 4. Check if the aggregate can be statically processed. If this is the
3386 -- case pass it as is to Gigi. Note that a necessary condition for
3387 -- static processing is that the aggregate be fully positional.
3389 -- 5. If in place aggregate expansion is possible (i.e. no need to create
3390 -- a temporary) then mark the aggregate as such and return. Otherwise
3391 -- create a new temporary and generate the appropriate initialization
3392 -- code.
3394 procedure Expand_Array_Aggregate (N : Node_Id) is
3395 Loc : constant Source_Ptr := Sloc (N);
3397 Typ : constant Entity_Id := Etype (N);
3398 Ctyp : constant Entity_Id := Component_Type (Typ);
3399 -- Typ is the correct constrained array subtype of the aggregate
3400 -- Ctyp is the corresponding component type.
3402 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
3403 -- Number of aggregate index dimensions
3405 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id;
3406 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id;
3407 -- Low and High bounds of the constraint for each aggregate index
3409 Aggr_Index_Typ : array (1 .. Aggr_Dimension) of Entity_Id;
3410 -- The type of each index
3412 Maybe_In_Place_OK : Boolean;
3413 -- If the type is neither controlled nor packed and the aggregate
3414 -- is the expression in an assignment, assignment in place may be
3415 -- possible, provided other conditions are met on the LHS.
3417 Others_Present : array (1 .. Aggr_Dimension) of Boolean :=
3418 (others => False);
3419 -- If Others_Present (J) is True, then there is an others choice
3420 -- in one of the sub-aggregates of N at dimension J.
3422 procedure Build_Constrained_Type (Positional : Boolean);
3423 -- If the subtype is not static or unconstrained, build a constrained
3424 -- type using the computable sizes of the aggregate and its sub-
3425 -- aggregates.
3427 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id);
3428 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
3429 -- by Index_Bounds.
3431 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos);
3432 -- Checks that in a multi-dimensional array aggregate all subaggregates
3433 -- corresponding to the same dimension have the same bounds.
3434 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
3435 -- corresponding to the sub-aggregate.
3437 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos);
3438 -- Computes the values of array Others_Present. Sub_Aggr is the
3439 -- array sub-aggregate we start the computation from. Dim is the
3440 -- dimension corresponding to the sub-aggregate.
3442 function Has_Address_Clause (D : Node_Id) return Boolean;
3443 -- If the aggregate is the expression in an object declaration, it
3444 -- cannot be expanded in place. This function does a lookahead in the
3445 -- current declarative part to find an address clause for the object
3446 -- being declared.
3448 function In_Place_Assign_OK return Boolean;
3449 -- Simple predicate to determine whether an aggregate assignment can
3450 -- be done in place, because none of the new values can depend on the
3451 -- components of the target of the assignment.
3453 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos);
3454 -- Checks that if an others choice is present in any sub-aggregate no
3455 -- aggregate index is outside the bounds of the index constraint.
3456 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
3457 -- corresponding to the sub-aggregate.
3459 ----------------------------
3460 -- Build_Constrained_Type --
3461 ----------------------------
3463 procedure Build_Constrained_Type (Positional : Boolean) is
3464 Loc : constant Source_Ptr := Sloc (N);
3465 Agg_Type : Entity_Id;
3466 Comp : Node_Id;
3467 Decl : Node_Id;
3468 Typ : constant Entity_Id := Etype (N);
3469 Indices : constant List_Id := New_List;
3470 Num : Int;
3471 Sub_Agg : Node_Id;
3473 begin
3474 Agg_Type :=
3475 Make_Defining_Identifier (
3476 Loc, New_Internal_Name ('A'));
3478 -- If the aggregate is purely positional, all its subaggregates
3479 -- have the same size. We collect the dimensions from the first
3480 -- subaggregate at each level.
3482 if Positional then
3483 Sub_Agg := N;
3485 for D in 1 .. Number_Dimensions (Typ) loop
3486 Comp := First (Expressions (Sub_Agg));
3488 Sub_Agg := Comp;
3489 Num := 0;
3491 while Present (Comp) loop
3492 Num := Num + 1;
3493 Next (Comp);
3494 end loop;
3496 Append (
3497 Make_Range (Loc,
3498 Low_Bound => Make_Integer_Literal (Loc, 1),
3499 High_Bound =>
3500 Make_Integer_Literal (Loc, Num)),
3501 Indices);
3502 end loop;
3504 else
3505 -- We know the aggregate type is unconstrained and the
3506 -- aggregate is not processable by the back end, therefore
3507 -- not necessarily positional. Retrieve the bounds of each
3508 -- dimension as computed earlier.
3510 for D in 1 .. Number_Dimensions (Typ) loop
3511 Append (
3512 Make_Range (Loc,
3513 Low_Bound => Aggr_Low (D),
3514 High_Bound => Aggr_High (D)),
3515 Indices);
3516 end loop;
3517 end if;
3519 Decl :=
3520 Make_Full_Type_Declaration (Loc,
3521 Defining_Identifier => Agg_Type,
3522 Type_Definition =>
3523 Make_Constrained_Array_Definition (Loc,
3524 Discrete_Subtype_Definitions => Indices,
3525 Component_Definition =>
3526 Make_Component_Definition (Loc,
3527 Aliased_Present => False,
3528 Subtype_Indication =>
3529 New_Occurrence_Of (Component_Type (Typ), Loc))));
3531 Insert_Action (N, Decl);
3532 Analyze (Decl);
3533 Set_Etype (N, Agg_Type);
3534 Set_Is_Itype (Agg_Type);
3535 Freeze_Itype (Agg_Type, N);
3536 end Build_Constrained_Type;
3538 ------------------
3539 -- Check_Bounds --
3540 ------------------
3542 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id) is
3543 Aggr_Lo : Node_Id;
3544 Aggr_Hi : Node_Id;
3546 Ind_Lo : Node_Id;
3547 Ind_Hi : Node_Id;
3549 Cond : Node_Id := Empty;
3551 begin
3552 Get_Index_Bounds (Aggr_Bounds, Aggr_Lo, Aggr_Hi);
3553 Get_Index_Bounds (Index_Bounds, Ind_Lo, Ind_Hi);
3555 -- Generate the following test:
3557 -- [constraint_error when
3558 -- Aggr_Lo <= Aggr_Hi and then
3559 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
3561 -- As an optimization try to see if some tests are trivially vacuos
3562 -- because we are comparing an expression against itself.
3564 if Aggr_Lo = Ind_Lo and then Aggr_Hi = Ind_Hi then
3565 Cond := Empty;
3567 elsif Aggr_Hi = Ind_Hi then
3568 Cond :=
3569 Make_Op_Lt (Loc,
3570 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3571 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo));
3573 elsif Aggr_Lo = Ind_Lo then
3574 Cond :=
3575 Make_Op_Gt (Loc,
3576 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
3577 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Hi));
3579 else
3580 Cond :=
3581 Make_Or_Else (Loc,
3582 Left_Opnd =>
3583 Make_Op_Lt (Loc,
3584 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3585 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo)),
3587 Right_Opnd =>
3588 Make_Op_Gt (Loc,
3589 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
3590 Right_Opnd => Duplicate_Subexpr (Ind_Hi)));
3591 end if;
3593 if Present (Cond) then
3594 Cond :=
3595 Make_And_Then (Loc,
3596 Left_Opnd =>
3597 Make_Op_Le (Loc,
3598 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3599 Right_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi)),
3601 Right_Opnd => Cond);
3603 Set_Analyzed (Left_Opnd (Left_Opnd (Cond)), False);
3604 Set_Analyzed (Right_Opnd (Left_Opnd (Cond)), False);
3605 Insert_Action (N,
3606 Make_Raise_Constraint_Error (Loc,
3607 Condition => Cond,
3608 Reason => CE_Length_Check_Failed));
3609 end if;
3610 end Check_Bounds;
3612 ----------------------------
3613 -- Check_Same_Aggr_Bounds --
3614 ----------------------------
3616 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos) is
3617 Sub_Lo : constant Node_Id := Low_Bound (Aggregate_Bounds (Sub_Aggr));
3618 Sub_Hi : constant Node_Id := High_Bound (Aggregate_Bounds (Sub_Aggr));
3619 -- The bounds of this specific sub-aggregate
3621 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
3622 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
3623 -- The bounds of the aggregate for this dimension
3625 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
3626 -- The index type for this dimension.xxx
3628 Cond : Node_Id := Empty;
3630 Assoc : Node_Id;
3631 Expr : Node_Id;
3633 begin
3634 -- If index checks are on generate the test
3636 -- [constraint_error when
3637 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
3639 -- As an optimization try to see if some tests are trivially vacuos
3640 -- because we are comparing an expression against itself. Also for
3641 -- the first dimension the test is trivially vacuous because there
3642 -- is just one aggregate for dimension 1.
3644 if Index_Checks_Suppressed (Ind_Typ) then
3645 Cond := Empty;
3647 elsif Dim = 1
3648 or else (Aggr_Lo = Sub_Lo and then Aggr_Hi = Sub_Hi)
3649 then
3650 Cond := Empty;
3652 elsif Aggr_Hi = Sub_Hi then
3653 Cond :=
3654 Make_Op_Ne (Loc,
3655 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3656 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo));
3658 elsif Aggr_Lo = Sub_Lo then
3659 Cond :=
3660 Make_Op_Ne (Loc,
3661 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
3662 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Hi));
3664 else
3665 Cond :=
3666 Make_Or_Else (Loc,
3667 Left_Opnd =>
3668 Make_Op_Ne (Loc,
3669 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3670 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo)),
3672 Right_Opnd =>
3673 Make_Op_Ne (Loc,
3674 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
3675 Right_Opnd => Duplicate_Subexpr (Sub_Hi)));
3676 end if;
3678 if Present (Cond) then
3679 Insert_Action (N,
3680 Make_Raise_Constraint_Error (Loc,
3681 Condition => Cond,
3682 Reason => CE_Length_Check_Failed));
3683 end if;
3685 -- Now look inside the sub-aggregate to see if there is more work
3687 if Dim < Aggr_Dimension then
3689 -- Process positional components
3691 if Present (Expressions (Sub_Aggr)) then
3692 Expr := First (Expressions (Sub_Aggr));
3693 while Present (Expr) loop
3694 Check_Same_Aggr_Bounds (Expr, Dim + 1);
3695 Next (Expr);
3696 end loop;
3697 end if;
3699 -- Process component associations
3701 if Present (Component_Associations (Sub_Aggr)) then
3702 Assoc := First (Component_Associations (Sub_Aggr));
3703 while Present (Assoc) loop
3704 Expr := Expression (Assoc);
3705 Check_Same_Aggr_Bounds (Expr, Dim + 1);
3706 Next (Assoc);
3707 end loop;
3708 end if;
3709 end if;
3710 end Check_Same_Aggr_Bounds;
3712 ----------------------------
3713 -- Compute_Others_Present --
3714 ----------------------------
3716 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos) is
3717 Assoc : Node_Id;
3718 Expr : Node_Id;
3720 begin
3721 if Present (Component_Associations (Sub_Aggr)) then
3722 Assoc := Last (Component_Associations (Sub_Aggr));
3724 if Nkind (First (Choices (Assoc))) = N_Others_Choice then
3725 Others_Present (Dim) := True;
3726 end if;
3727 end if;
3729 -- Now look inside the sub-aggregate to see if there is more work
3731 if Dim < Aggr_Dimension then
3733 -- Process positional components
3735 if Present (Expressions (Sub_Aggr)) then
3736 Expr := First (Expressions (Sub_Aggr));
3737 while Present (Expr) loop
3738 Compute_Others_Present (Expr, Dim + 1);
3739 Next (Expr);
3740 end loop;
3741 end if;
3743 -- Process component associations
3745 if Present (Component_Associations (Sub_Aggr)) then
3746 Assoc := First (Component_Associations (Sub_Aggr));
3747 while Present (Assoc) loop
3748 Expr := Expression (Assoc);
3749 Compute_Others_Present (Expr, Dim + 1);
3750 Next (Assoc);
3751 end loop;
3752 end if;
3753 end if;
3754 end Compute_Others_Present;
3756 ------------------------
3757 -- Has_Address_Clause --
3758 ------------------------
3760 function Has_Address_Clause (D : Node_Id) return Boolean is
3761 Id : constant Entity_Id := Defining_Identifier (D);
3762 Decl : Node_Id := Next (D);
3764 begin
3765 while Present (Decl) loop
3766 if Nkind (Decl) = N_At_Clause
3767 and then Chars (Identifier (Decl)) = Chars (Id)
3768 then
3769 return True;
3771 elsif Nkind (Decl) = N_Attribute_Definition_Clause
3772 and then Chars (Decl) = Name_Address
3773 and then Chars (Name (Decl)) = Chars (Id)
3774 then
3775 return True;
3776 end if;
3778 Next (Decl);
3779 end loop;
3781 return False;
3782 end Has_Address_Clause;
3784 ------------------------
3785 -- In_Place_Assign_OK --
3786 ------------------------
3788 function In_Place_Assign_OK return Boolean is
3789 Aggr_In : Node_Id;
3790 Aggr_Lo : Node_Id;
3791 Aggr_Hi : Node_Id;
3792 Obj_In : Node_Id;
3793 Obj_Lo : Node_Id;
3794 Obj_Hi : Node_Id;
3796 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean;
3797 -- Aggregates that consist of a single Others choice are safe
3798 -- if the single expression is.
3800 function Safe_Aggregate (Aggr : Node_Id) return Boolean;
3801 -- Check recursively that each component of a (sub)aggregate does
3802 -- not depend on the variable being assigned to.
3804 function Safe_Component (Expr : Node_Id) return Boolean;
3805 -- Verify that an expression cannot depend on the variable being
3806 -- assigned to. Room for improvement here (but less than before).
3808 -------------------------
3809 -- Is_Others_Aggregate --
3810 -------------------------
3812 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean is
3813 begin
3814 return No (Expressions (Aggr))
3815 and then Nkind
3816 (First (Choices (First (Component_Associations (Aggr)))))
3817 = N_Others_Choice;
3818 end Is_Others_Aggregate;
3820 --------------------
3821 -- Safe_Aggregate --
3822 --------------------
3824 function Safe_Aggregate (Aggr : Node_Id) return Boolean is
3825 Expr : Node_Id;
3827 begin
3828 if Present (Expressions (Aggr)) then
3829 Expr := First (Expressions (Aggr));
3831 while Present (Expr) loop
3832 if Nkind (Expr) = N_Aggregate then
3833 if not Safe_Aggregate (Expr) then
3834 return False;
3835 end if;
3837 elsif not Safe_Component (Expr) then
3838 return False;
3839 end if;
3841 Next (Expr);
3842 end loop;
3843 end if;
3845 if Present (Component_Associations (Aggr)) then
3846 Expr := First (Component_Associations (Aggr));
3848 while Present (Expr) loop
3849 if Nkind (Expression (Expr)) = N_Aggregate then
3850 if not Safe_Aggregate (Expression (Expr)) then
3851 return False;
3852 end if;
3854 elsif not Safe_Component (Expression (Expr)) then
3855 return False;
3856 end if;
3858 Next (Expr);
3859 end loop;
3860 end if;
3862 return True;
3863 end Safe_Aggregate;
3865 --------------------
3866 -- Safe_Component --
3867 --------------------
3869 function Safe_Component (Expr : Node_Id) return Boolean is
3870 Comp : Node_Id := Expr;
3872 function Check_Component (Comp : Node_Id) return Boolean;
3873 -- Do the recursive traversal, after copy
3875 ---------------------
3876 -- Check_Component --
3877 ---------------------
3879 function Check_Component (Comp : Node_Id) return Boolean is
3880 begin
3881 if Is_Overloaded (Comp) then
3882 return False;
3883 end if;
3885 return Compile_Time_Known_Value (Comp)
3887 or else (Is_Entity_Name (Comp)
3888 and then Present (Entity (Comp))
3889 and then No (Renamed_Object (Entity (Comp))))
3891 or else (Nkind (Comp) = N_Attribute_Reference
3892 and then Check_Component (Prefix (Comp)))
3894 or else (Nkind (Comp) in N_Binary_Op
3895 and then Check_Component (Left_Opnd (Comp))
3896 and then Check_Component (Right_Opnd (Comp)))
3898 or else (Nkind (Comp) in N_Unary_Op
3899 and then Check_Component (Right_Opnd (Comp)))
3901 or else (Nkind (Comp) = N_Selected_Component
3902 and then Check_Component (Prefix (Comp)))
3904 or else (Nkind (Comp) = N_Unchecked_Type_Conversion
3905 and then Check_Component (Expression (Comp)));
3906 end Check_Component;
3908 -- Start of processing for Safe_Component
3910 begin
3911 -- If the component appears in an association that may
3912 -- correspond to more than one element, it is not analyzed
3913 -- before the expansion into assignments, to avoid side effects.
3914 -- We analyze, but do not resolve the copy, to obtain sufficient
3915 -- entity information for the checks that follow. If component is
3916 -- overloaded we assume an unsafe function call.
3918 if not Analyzed (Comp) then
3919 if Is_Overloaded (Expr) then
3920 return False;
3922 elsif Nkind (Expr) = N_Aggregate
3923 and then not Is_Others_Aggregate (Expr)
3924 then
3925 return False;
3927 elsif Nkind (Expr) = N_Allocator then
3929 -- For now, too complex to analyze
3931 return False;
3932 end if;
3934 Comp := New_Copy_Tree (Expr);
3935 Set_Parent (Comp, Parent (Expr));
3936 Analyze (Comp);
3937 end if;
3939 if Nkind (Comp) = N_Aggregate then
3940 return Safe_Aggregate (Comp);
3941 else
3942 return Check_Component (Comp);
3943 end if;
3944 end Safe_Component;
3946 -- Start of processing for In_Place_Assign_OK
3948 begin
3949 if Present (Component_Associations (N)) then
3951 -- On assignment, sliding can take place, so we cannot do the
3952 -- assignment in place unless the bounds of the aggregate are
3953 -- statically equal to those of the target.
3955 -- If the aggregate is given by an others choice, the bounds
3956 -- are derived from the left-hand side, and the assignment is
3957 -- safe if the expression is.
3959 if Is_Others_Aggregate (N) then
3960 return
3961 Safe_Component
3962 (Expression (First (Component_Associations (N))));
3963 end if;
3965 Aggr_In := First_Index (Etype (N));
3966 if Nkind (Parent (N)) = N_Assignment_Statement then
3967 Obj_In := First_Index (Etype (Name (Parent (N))));
3969 else
3970 -- Context is an allocator. Check bounds of aggregate
3971 -- against given type in qualified expression.
3973 pragma Assert (Nkind (Parent (Parent (N))) = N_Allocator);
3974 Obj_In :=
3975 First_Index (Etype (Entity (Subtype_Mark (Parent (N)))));
3976 end if;
3978 while Present (Aggr_In) loop
3979 Get_Index_Bounds (Aggr_In, Aggr_Lo, Aggr_Hi);
3980 Get_Index_Bounds (Obj_In, Obj_Lo, Obj_Hi);
3982 if not Compile_Time_Known_Value (Aggr_Lo)
3983 or else not Compile_Time_Known_Value (Aggr_Hi)
3984 or else not Compile_Time_Known_Value (Obj_Lo)
3985 or else not Compile_Time_Known_Value (Obj_Hi)
3986 or else Expr_Value (Aggr_Lo) /= Expr_Value (Obj_Lo)
3987 or else Expr_Value (Aggr_Hi) /= Expr_Value (Obj_Hi)
3988 then
3989 return False;
3990 end if;
3992 Next_Index (Aggr_In);
3993 Next_Index (Obj_In);
3994 end loop;
3995 end if;
3997 -- Now check the component values themselves
3999 return Safe_Aggregate (N);
4000 end In_Place_Assign_OK;
4002 ------------------
4003 -- Others_Check --
4004 ------------------
4006 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos) is
4007 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
4008 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
4009 -- The bounds of the aggregate for this dimension
4011 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
4012 -- The index type for this dimension
4014 Need_To_Check : Boolean := False;
4016 Choices_Lo : Node_Id := Empty;
4017 Choices_Hi : Node_Id := Empty;
4018 -- The lowest and highest discrete choices for a named sub-aggregate
4020 Nb_Choices : Int := -1;
4021 -- The number of discrete non-others choices in this sub-aggregate
4023 Nb_Elements : Uint := Uint_0;
4024 -- The number of elements in a positional aggregate
4026 Cond : Node_Id := Empty;
4028 Assoc : Node_Id;
4029 Choice : Node_Id;
4030 Expr : Node_Id;
4032 begin
4033 -- Check if we have an others choice. If we do make sure that this
4034 -- sub-aggregate contains at least one element in addition to the
4035 -- others choice.
4037 if Range_Checks_Suppressed (Ind_Typ) then
4038 Need_To_Check := False;
4040 elsif Present (Expressions (Sub_Aggr))
4041 and then Present (Component_Associations (Sub_Aggr))
4042 then
4043 Need_To_Check := True;
4045 elsif Present (Component_Associations (Sub_Aggr)) then
4046 Assoc := Last (Component_Associations (Sub_Aggr));
4048 if Nkind (First (Choices (Assoc))) /= N_Others_Choice then
4049 Need_To_Check := False;
4051 else
4052 -- Count the number of discrete choices. Start with -1
4053 -- because the others choice does not count.
4055 Nb_Choices := -1;
4056 Assoc := First (Component_Associations (Sub_Aggr));
4057 while Present (Assoc) loop
4058 Choice := First (Choices (Assoc));
4059 while Present (Choice) loop
4060 Nb_Choices := Nb_Choices + 1;
4061 Next (Choice);
4062 end loop;
4064 Next (Assoc);
4065 end loop;
4067 -- If there is only an others choice nothing to do
4069 Need_To_Check := (Nb_Choices > 0);
4070 end if;
4072 else
4073 Need_To_Check := False;
4074 end if;
4076 -- If we are dealing with a positional sub-aggregate with an
4077 -- others choice then compute the number or positional elements.
4079 if Need_To_Check and then Present (Expressions (Sub_Aggr)) then
4080 Expr := First (Expressions (Sub_Aggr));
4081 Nb_Elements := Uint_0;
4082 while Present (Expr) loop
4083 Nb_Elements := Nb_Elements + 1;
4084 Next (Expr);
4085 end loop;
4087 -- If the aggregate contains discrete choices and an others choice
4088 -- compute the smallest and largest discrete choice values.
4090 elsif Need_To_Check then
4091 Compute_Choices_Lo_And_Choices_Hi : declare
4093 Table : Case_Table_Type (1 .. Nb_Choices);
4094 -- Used to sort all the different choice values
4096 J : Pos := 1;
4097 Low : Node_Id;
4098 High : Node_Id;
4100 begin
4101 Assoc := First (Component_Associations (Sub_Aggr));
4102 while Present (Assoc) loop
4103 Choice := First (Choices (Assoc));
4104 while Present (Choice) loop
4105 if Nkind (Choice) = N_Others_Choice then
4106 exit;
4107 end if;
4109 Get_Index_Bounds (Choice, Low, High);
4110 Table (J).Choice_Lo := Low;
4111 Table (J).Choice_Hi := High;
4113 J := J + 1;
4114 Next (Choice);
4115 end loop;
4117 Next (Assoc);
4118 end loop;
4120 -- Sort the discrete choices
4122 Sort_Case_Table (Table);
4124 Choices_Lo := Table (1).Choice_Lo;
4125 Choices_Hi := Table (Nb_Choices).Choice_Hi;
4126 end Compute_Choices_Lo_And_Choices_Hi;
4127 end if;
4129 -- If no others choice in this sub-aggregate, or the aggregate
4130 -- comprises only an others choice, nothing to do.
4132 if not Need_To_Check then
4133 Cond := Empty;
4135 -- If we are dealing with an aggregate containing an others
4136 -- choice and positional components, we generate the following test:
4138 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
4139 -- Ind_Typ'Pos (Aggr_Hi)
4140 -- then
4141 -- raise Constraint_Error;
4142 -- end if;
4144 elsif Nb_Elements > Uint_0 then
4145 Cond :=
4146 Make_Op_Gt (Loc,
4147 Left_Opnd =>
4148 Make_Op_Add (Loc,
4149 Left_Opnd =>
4150 Make_Attribute_Reference (Loc,
4151 Prefix => New_Reference_To (Ind_Typ, Loc),
4152 Attribute_Name => Name_Pos,
4153 Expressions =>
4154 New_List
4155 (Duplicate_Subexpr_Move_Checks (Aggr_Lo))),
4156 Right_Opnd => Make_Integer_Literal (Loc, Nb_Elements - 1)),
4158 Right_Opnd =>
4159 Make_Attribute_Reference (Loc,
4160 Prefix => New_Reference_To (Ind_Typ, Loc),
4161 Attribute_Name => Name_Pos,
4162 Expressions => New_List (
4163 Duplicate_Subexpr_Move_Checks (Aggr_Hi))));
4165 -- If we are dealing with an aggregate containing an others
4166 -- choice and discrete choices we generate the following test:
4168 -- [constraint_error when
4169 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
4171 else
4172 Cond :=
4173 Make_Or_Else (Loc,
4174 Left_Opnd =>
4175 Make_Op_Lt (Loc,
4176 Left_Opnd =>
4177 Duplicate_Subexpr_Move_Checks (Choices_Lo),
4178 Right_Opnd =>
4179 Duplicate_Subexpr_Move_Checks (Aggr_Lo)),
4181 Right_Opnd =>
4182 Make_Op_Gt (Loc,
4183 Left_Opnd =>
4184 Duplicate_Subexpr (Choices_Hi),
4185 Right_Opnd =>
4186 Duplicate_Subexpr (Aggr_Hi)));
4187 end if;
4189 if Present (Cond) then
4190 Insert_Action (N,
4191 Make_Raise_Constraint_Error (Loc,
4192 Condition => Cond,
4193 Reason => CE_Length_Check_Failed));
4194 end if;
4196 -- Now look inside the sub-aggregate to see if there is more work
4198 if Dim < Aggr_Dimension then
4200 -- Process positional components
4202 if Present (Expressions (Sub_Aggr)) then
4203 Expr := First (Expressions (Sub_Aggr));
4204 while Present (Expr) loop
4205 Others_Check (Expr, Dim + 1);
4206 Next (Expr);
4207 end loop;
4208 end if;
4210 -- Process component associations
4212 if Present (Component_Associations (Sub_Aggr)) then
4213 Assoc := First (Component_Associations (Sub_Aggr));
4214 while Present (Assoc) loop
4215 Expr := Expression (Assoc);
4216 Others_Check (Expr, Dim + 1);
4217 Next (Assoc);
4218 end loop;
4219 end if;
4220 end if;
4221 end Others_Check;
4223 -- Remaining Expand_Array_Aggregate variables
4225 Tmp : Entity_Id;
4226 -- Holds the temporary aggregate value
4228 Tmp_Decl : Node_Id;
4229 -- Holds the declaration of Tmp
4231 Aggr_Code : List_Id;
4232 Parent_Node : Node_Id;
4233 Parent_Kind : Node_Kind;
4235 -- Start of processing for Expand_Array_Aggregate
4237 begin
4238 -- Do not touch the special aggregates of attributes used for Asm calls
4240 if Is_RTE (Ctyp, RE_Asm_Input_Operand)
4241 or else Is_RTE (Ctyp, RE_Asm_Output_Operand)
4242 then
4243 return;
4244 end if;
4246 -- If the semantic analyzer has determined that aggregate N will raise
4247 -- Constraint_Error at run-time, then the aggregate node has been
4248 -- replaced with an N_Raise_Constraint_Error node and we should
4249 -- never get here.
4251 pragma Assert (not Raises_Constraint_Error (N));
4253 -- STEP 1a
4255 -- Check that the index range defined by aggregate bounds is
4256 -- compatible with corresponding index subtype.
4258 Index_Compatibility_Check : declare
4259 Aggr_Index_Range : Node_Id := First_Index (Typ);
4260 -- The current aggregate index range
4262 Index_Constraint : Node_Id := First_Index (Etype (Typ));
4263 -- The corresponding index constraint against which we have to
4264 -- check the above aggregate index range.
4266 begin
4267 Compute_Others_Present (N, 1);
4269 for J in 1 .. Aggr_Dimension loop
4270 -- There is no need to emit a check if an others choice is
4271 -- present for this array aggregate dimension since in this
4272 -- case one of N's sub-aggregates has taken its bounds from the
4273 -- context and these bounds must have been checked already. In
4274 -- addition all sub-aggregates corresponding to the same
4275 -- dimension must all have the same bounds (checked in (c) below).
4277 if not Range_Checks_Suppressed (Etype (Index_Constraint))
4278 and then not Others_Present (J)
4279 then
4280 -- We don't use Checks.Apply_Range_Check here because it
4281 -- emits a spurious check. Namely it checks that the range
4282 -- defined by the aggregate bounds is non empty. But we know
4283 -- this already if we get here.
4285 Check_Bounds (Aggr_Index_Range, Index_Constraint);
4286 end if;
4288 -- Save the low and high bounds of the aggregate index as well
4289 -- as the index type for later use in checks (b) and (c) below.
4291 Aggr_Low (J) := Low_Bound (Aggr_Index_Range);
4292 Aggr_High (J) := High_Bound (Aggr_Index_Range);
4294 Aggr_Index_Typ (J) := Etype (Index_Constraint);
4296 Next_Index (Aggr_Index_Range);
4297 Next_Index (Index_Constraint);
4298 end loop;
4299 end Index_Compatibility_Check;
4301 -- STEP 1b
4303 -- If an others choice is present check that no aggregate
4304 -- index is outside the bounds of the index constraint.
4306 Others_Check (N, 1);
4308 -- STEP 1c
4310 -- For multidimensional arrays make sure that all subaggregates
4311 -- corresponding to the same dimension have the same bounds.
4313 if Aggr_Dimension > 1 then
4314 Check_Same_Aggr_Bounds (N, 1);
4315 end if;
4317 -- STEP 2
4319 -- Here we test for is packed array aggregate that we can handle
4320 -- at compile time. If so, return with transformation done. Note
4321 -- that we do this even if the aggregate is nested, because once
4322 -- we have done this processing, there is no more nested aggregate!
4324 if Packed_Array_Aggregate_Handled (N) then
4325 return;
4326 end if;
4328 -- At this point we try to convert to positional form
4330 Convert_To_Positional (N);
4332 -- if the result is no longer an aggregate (e.g. it may be a string
4333 -- literal, or a temporary which has the needed value), then we are
4334 -- done, since there is no longer a nested aggregate.
4336 if Nkind (N) /= N_Aggregate then
4337 return;
4339 -- We are also done if the result is an analyzed aggregate
4340 -- This case could use more comments ???
4342 elsif Analyzed (N)
4343 and then N /= Original_Node (N)
4344 then
4345 return;
4346 end if;
4348 -- Now see if back end processing is possible
4350 if Backend_Processing_Possible (N) then
4352 -- If the aggregate is static but the constraints are not, build
4353 -- a static subtype for the aggregate, so that Gigi can place it
4354 -- in static memory. Perform an unchecked_conversion to the non-
4355 -- static type imposed by the context.
4357 declare
4358 Itype : constant Entity_Id := Etype (N);
4359 Index : Node_Id;
4360 Needs_Type : Boolean := False;
4362 begin
4363 Index := First_Index (Itype);
4365 while Present (Index) loop
4366 if not Is_Static_Subtype (Etype (Index)) then
4367 Needs_Type := True;
4368 exit;
4369 else
4370 Next_Index (Index);
4371 end if;
4372 end loop;
4374 if Needs_Type then
4375 Build_Constrained_Type (Positional => True);
4376 Rewrite (N, Unchecked_Convert_To (Itype, N));
4377 Analyze (N);
4378 end if;
4379 end;
4381 return;
4382 end if;
4384 -- STEP 3
4386 -- Delay expansion for nested aggregates it will be taken care of
4387 -- when the parent aggregate is expanded
4389 Parent_Node := Parent (N);
4390 Parent_Kind := Nkind (Parent_Node);
4392 if Parent_Kind = N_Qualified_Expression then
4393 Parent_Node := Parent (Parent_Node);
4394 Parent_Kind := Nkind (Parent_Node);
4395 end if;
4397 if Parent_Kind = N_Aggregate
4398 or else Parent_Kind = N_Extension_Aggregate
4399 or else Parent_Kind = N_Component_Association
4400 or else (Parent_Kind = N_Object_Declaration
4401 and then Controlled_Type (Typ))
4402 or else (Parent_Kind = N_Assignment_Statement
4403 and then Inside_Init_Proc)
4404 then
4405 Set_Expansion_Delayed (N);
4406 return;
4407 end if;
4409 -- STEP 4
4411 -- Look if in place aggregate expansion is possible
4413 -- For object declarations we build the aggregate in place, unless
4414 -- the array is bit-packed or the component is controlled.
4416 -- For assignments we do the assignment in place if all the component
4417 -- associations have compile-time known values. For other cases we
4418 -- create a temporary. The analysis for safety of on-line assignment
4419 -- is delicate, i.e. we don't know how to do it fully yet ???
4421 -- For allocators we assign to the designated object in place if the
4422 -- aggregate meets the same conditions as other in-place assignments.
4423 -- In this case the aggregate may not come from source but was created
4424 -- for default initialization, e.g. with Initialize_Scalars.
4426 if Requires_Transient_Scope (Typ) then
4427 Establish_Transient_Scope
4428 (N, Sec_Stack => Has_Controlled_Component (Typ));
4429 end if;
4431 if Has_Default_Init_Comps (N) then
4432 Maybe_In_Place_OK := False;
4434 elsif Is_Bit_Packed_Array (Typ)
4435 or else Has_Controlled_Component (Typ)
4436 then
4437 Maybe_In_Place_OK := False;
4439 else
4440 Maybe_In_Place_OK :=
4441 (Nkind (Parent (N)) = N_Assignment_Statement
4442 and then Comes_From_Source (N)
4443 and then In_Place_Assign_OK)
4445 or else
4446 (Nkind (Parent (Parent (N))) = N_Allocator
4447 and then In_Place_Assign_OK);
4448 end if;
4450 if not Has_Default_Init_Comps (N)
4451 and then Comes_From_Source (Parent (N))
4452 and then Nkind (Parent (N)) = N_Object_Declaration
4453 and then not
4454 Must_Slide (Etype (Defining_Identifier (Parent (N))), Typ)
4455 and then N = Expression (Parent (N))
4456 and then not Is_Bit_Packed_Array (Typ)
4457 and then not Has_Controlled_Component (Typ)
4458 and then not Has_Address_Clause (Parent (N))
4459 then
4460 Tmp := Defining_Identifier (Parent (N));
4461 Set_No_Initialization (Parent (N));
4462 Set_Expression (Parent (N), Empty);
4464 -- Set the type of the entity, for use in the analysis of the
4465 -- subsequent indexed assignments. If the nominal type is not
4466 -- constrained, build a subtype from the known bounds of the
4467 -- aggregate. If the declaration has a subtype mark, use it,
4468 -- otherwise use the itype of the aggregate.
4470 if not Is_Constrained (Typ) then
4471 Build_Constrained_Type (Positional => False);
4472 elsif Is_Entity_Name (Object_Definition (Parent (N)))
4473 and then Is_Constrained (Entity (Object_Definition (Parent (N))))
4474 then
4475 Set_Etype (Tmp, Entity (Object_Definition (Parent (N))));
4476 else
4477 Set_Size_Known_At_Compile_Time (Typ, False);
4478 Set_Etype (Tmp, Typ);
4479 end if;
4481 elsif Maybe_In_Place_OK
4482 and then Nkind (Parent (N)) = N_Qualified_Expression
4483 and then Nkind (Parent (Parent (N))) = N_Allocator
4484 then
4485 Set_Expansion_Delayed (N);
4486 return;
4488 -- In the remaining cases the aggregate is the RHS of an assignment
4490 elsif Maybe_In_Place_OK
4491 and then Is_Entity_Name (Name (Parent (N)))
4492 then
4493 Tmp := Entity (Name (Parent (N)));
4495 if Etype (Tmp) /= Etype (N) then
4496 Apply_Length_Check (N, Etype (Tmp));
4498 if Nkind (N) = N_Raise_Constraint_Error then
4500 -- Static error, nothing further to expand
4502 return;
4503 end if;
4504 end if;
4506 elsif Maybe_In_Place_OK
4507 and then Nkind (Name (Parent (N))) = N_Explicit_Dereference
4508 and then Is_Entity_Name (Prefix (Name (Parent (N))))
4509 then
4510 Tmp := Name (Parent (N));
4512 if Etype (Tmp) /= Etype (N) then
4513 Apply_Length_Check (N, Etype (Tmp));
4514 end if;
4516 elsif Maybe_In_Place_OK
4517 and then Nkind (Name (Parent (N))) = N_Slice
4518 and then Safe_Slice_Assignment (N)
4519 then
4520 -- Safe_Slice_Assignment rewrites assignment as a loop
4522 return;
4524 -- Step 5
4526 -- In place aggregate expansion is not possible
4528 else
4529 Maybe_In_Place_OK := False;
4530 Tmp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4531 Tmp_Decl :=
4532 Make_Object_Declaration
4533 (Loc,
4534 Defining_Identifier => Tmp,
4535 Object_Definition => New_Occurrence_Of (Typ, Loc));
4536 Set_No_Initialization (Tmp_Decl, True);
4538 -- If we are within a loop, the temporary will be pushed on the
4539 -- stack at each iteration. If the aggregate is the expression for
4540 -- an allocator, it will be immediately copied to the heap and can
4541 -- be reclaimed at once. We create a transient scope around the
4542 -- aggregate for this purpose.
4544 if Ekind (Current_Scope) = E_Loop
4545 and then Nkind (Parent (Parent (N))) = N_Allocator
4546 then
4547 Establish_Transient_Scope (N, False);
4548 end if;
4550 Insert_Action (N, Tmp_Decl);
4551 end if;
4553 -- Construct and insert the aggregate code. We can safely suppress
4554 -- index checks because this code is guaranteed not to raise CE
4555 -- on index checks. However we should *not* suppress all checks.
4557 declare
4558 Target : Node_Id;
4560 begin
4561 if Nkind (Tmp) = N_Defining_Identifier then
4562 Target := New_Reference_To (Tmp, Loc);
4564 else
4566 if Has_Default_Init_Comps (N) then
4568 -- Ada 2005 (AI-287): This case has not been analyzed???
4570 raise Program_Error;
4571 end if;
4573 -- Name in assignment is explicit dereference
4575 Target := New_Copy (Tmp);
4576 end if;
4578 Aggr_Code :=
4579 Build_Array_Aggr_Code (N,
4580 Ctype => Ctyp,
4581 Index => First_Index (Typ),
4582 Into => Target,
4583 Scalar_Comp => Is_Scalar_Type (Ctyp));
4584 end;
4586 if Comes_From_Source (Tmp) then
4587 Insert_Actions_After (Parent (N), Aggr_Code);
4589 else
4590 Insert_Actions (N, Aggr_Code);
4591 end if;
4593 -- If the aggregate has been assigned in place, remove the original
4594 -- assignment.
4596 if Nkind (Parent (N)) = N_Assignment_Statement
4597 and then Maybe_In_Place_OK
4598 then
4599 Rewrite (Parent (N), Make_Null_Statement (Loc));
4601 elsif Nkind (Parent (N)) /= N_Object_Declaration
4602 or else Tmp /= Defining_Identifier (Parent (N))
4603 then
4604 Rewrite (N, New_Occurrence_Of (Tmp, Loc));
4605 Analyze_And_Resolve (N, Typ);
4606 end if;
4607 end Expand_Array_Aggregate;
4609 ------------------------
4610 -- Expand_N_Aggregate --
4611 ------------------------
4613 procedure Expand_N_Aggregate (N : Node_Id) is
4614 begin
4615 if Is_Record_Type (Etype (N)) then
4616 Expand_Record_Aggregate (N);
4617 else
4618 Expand_Array_Aggregate (N);
4619 end if;
4621 exception
4622 when RE_Not_Available =>
4623 return;
4624 end Expand_N_Aggregate;
4626 ----------------------------------
4627 -- Expand_N_Extension_Aggregate --
4628 ----------------------------------
4630 -- If the ancestor part is an expression, add a component association for
4631 -- the parent field. If the type of the ancestor part is not the direct
4632 -- parent of the expected type, build recursively the needed ancestors.
4633 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
4634 -- ration for a temporary of the expected type, followed by individual
4635 -- assignments to the given components.
4637 procedure Expand_N_Extension_Aggregate (N : Node_Id) is
4638 Loc : constant Source_Ptr := Sloc (N);
4639 A : constant Node_Id := Ancestor_Part (N);
4640 Typ : constant Entity_Id := Etype (N);
4642 begin
4643 -- If the ancestor is a subtype mark, an init proc must be called
4644 -- on the resulting object which thus has to be materialized in
4645 -- the front-end
4647 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
4648 Convert_To_Assignments (N, Typ);
4650 -- The extension aggregate is transformed into a record aggregate
4651 -- of the following form (c1 and c2 are inherited components)
4653 -- (Exp with c3 => a, c4 => b)
4654 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c1 => a, c2 => b)
4656 else
4657 Set_Etype (N, Typ);
4659 -- No tag is needed in the case of Java_VM
4661 if Java_VM then
4662 Expand_Record_Aggregate (N,
4663 Parent_Expr => A);
4664 else
4665 Expand_Record_Aggregate (N,
4666 Orig_Tag =>
4667 New_Occurrence_Of
4668 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc),
4669 Parent_Expr => A);
4670 end if;
4671 end if;
4673 exception
4674 when RE_Not_Available =>
4675 return;
4676 end Expand_N_Extension_Aggregate;
4678 -----------------------------
4679 -- Expand_Record_Aggregate --
4680 -----------------------------
4682 procedure Expand_Record_Aggregate
4683 (N : Node_Id;
4684 Orig_Tag : Node_Id := Empty;
4685 Parent_Expr : Node_Id := Empty)
4687 Loc : constant Source_Ptr := Sloc (N);
4688 Comps : constant List_Id := Component_Associations (N);
4689 Typ : constant Entity_Id := Etype (N);
4690 Base_Typ : constant Entity_Id := Base_Type (Typ);
4692 function Has_Delayed_Nested_Aggregate_Or_Tagged_Comps return Boolean;
4693 -- Checks the presence of a nested aggregate which needs Late_Expansion
4694 -- or the presence of tagged components which may need tag adjustment.
4696 --------------------------------------------------
4697 -- Has_Delayed_Nested_Aggregate_Or_Tagged_Comps --
4698 --------------------------------------------------
4700 function Has_Delayed_Nested_Aggregate_Or_Tagged_Comps return Boolean is
4701 C : Node_Id;
4702 Expr_Q : Node_Id;
4704 begin
4705 if No (Comps) then
4706 return False;
4707 end if;
4709 C := First (Comps);
4710 while Present (C) loop
4711 if Nkind (Expression (C)) = N_Qualified_Expression then
4712 Expr_Q := Expression (Expression (C));
4713 else
4714 Expr_Q := Expression (C);
4715 end if;
4717 -- Return true if the aggregate has any associations for
4718 -- tagged components that may require tag adjustment.
4719 -- These are cases where the source expression may have
4720 -- a tag that could differ from the component tag (e.g.,
4721 -- can occur for type conversions and formal parameters).
4722 -- (Tag adjustment is not needed if Java_VM because object
4723 -- tags are implicit in the JVM.)
4725 if Is_Tagged_Type (Etype (Expr_Q))
4726 and then (Nkind (Expr_Q) = N_Type_Conversion
4727 or else (Is_Entity_Name (Expr_Q)
4728 and then Ekind (Entity (Expr_Q)) in Formal_Kind))
4729 and then not Java_VM
4730 then
4731 return True;
4732 end if;
4734 if Is_Delayed_Aggregate (Expr_Q) then
4735 return True;
4736 end if;
4738 Next (C);
4739 end loop;
4741 return False;
4742 end Has_Delayed_Nested_Aggregate_Or_Tagged_Comps;
4744 -- Remaining Expand_Record_Aggregate variables
4746 Tag_Value : Node_Id;
4747 Comp : Entity_Id;
4748 New_Comp : Node_Id;
4750 -- Start of processing for Expand_Record_Aggregate
4752 begin
4753 -- If the aggregate is to be assigned to an atomic variable, we
4754 -- have to prevent a piecemeal assignment even if the aggregate
4755 -- is to be expanded. We create a temporary for the aggregate, and
4756 -- assign the temporary instead, so that the back end can generate
4757 -- an atomic move for it.
4759 if Is_Atomic (Typ)
4760 and then (Nkind (Parent (N)) = N_Object_Declaration
4761 or else Nkind (Parent (N)) = N_Assignment_Statement)
4762 and then Comes_From_Source (Parent (N))
4763 then
4764 Expand_Atomic_Aggregate (N, Typ);
4765 return;
4766 end if;
4768 -- Gigi doesn't handle properly temporaries of variable size
4769 -- so we generate it in the front-end
4771 if not Size_Known_At_Compile_Time (Typ) then
4772 Convert_To_Assignments (N, Typ);
4774 -- Temporaries for controlled aggregates need to be attached to a
4775 -- final chain in order to be properly finalized, so it has to
4776 -- be created in the front-end
4778 elsif Is_Controlled (Typ)
4779 or else Has_Controlled_Component (Base_Type (Typ))
4780 then
4781 Convert_To_Assignments (N, Typ);
4783 -- Ada 2005 (AI-287): In case of default initialized components we
4784 -- convert the aggregate into assignments.
4786 elsif Has_Default_Init_Comps (N) then
4787 Convert_To_Assignments (N, Typ);
4789 elsif Has_Delayed_Nested_Aggregate_Or_Tagged_Comps then
4790 Convert_To_Assignments (N, Typ);
4792 -- If an ancestor is private, some components are not inherited and
4793 -- we cannot expand into a record aggregate
4795 elsif Has_Private_Ancestor (Typ) then
4796 Convert_To_Assignments (N, Typ);
4798 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
4799 -- is not able to handle the aggregate for Late_Request.
4801 elsif Is_Tagged_Type (Typ) and then Has_Discriminants (Typ) then
4802 Convert_To_Assignments (N, Typ);
4804 -- If some components are mutable, the size of the aggregate component
4805 -- may be disctinct from the default size of the type component, so
4806 -- we need to expand to insure that the back-end copies the proper
4807 -- size of the data.
4809 elsif Has_Mutable_Components (Typ) then
4810 Convert_To_Assignments (N, Typ);
4812 -- If the type involved has any non-bit aligned components, then
4813 -- we are not sure that the back end can handle this case correctly.
4815 elsif Type_May_Have_Bit_Aligned_Components (Typ) then
4816 Convert_To_Assignments (N, Typ);
4818 -- In all other cases we generate a proper aggregate that
4819 -- can be handled by gigi.
4821 else
4822 -- If no discriminants, nothing special to do
4824 if not Has_Discriminants (Typ) then
4825 null;
4827 -- Case of discriminants present
4829 elsif Is_Derived_Type (Typ) then
4831 -- For untagged types, non-stored discriminants are replaced
4832 -- with stored discriminants, which are the ones that gigi uses
4833 -- to describe the type and its components.
4835 Generate_Aggregate_For_Derived_Type : declare
4836 Constraints : constant List_Id := New_List;
4837 First_Comp : Node_Id;
4838 Discriminant : Entity_Id;
4839 Decl : Node_Id;
4840 Num_Disc : Int := 0;
4841 Num_Gird : Int := 0;
4843 procedure Prepend_Stored_Values (T : Entity_Id);
4844 -- Scan the list of stored discriminants of the type, and
4845 -- add their values to the aggregate being built.
4847 ---------------------------
4848 -- Prepend_Stored_Values --
4849 ---------------------------
4851 procedure Prepend_Stored_Values (T : Entity_Id) is
4852 begin
4853 Discriminant := First_Stored_Discriminant (T);
4855 while Present (Discriminant) loop
4856 New_Comp :=
4857 Make_Component_Association (Loc,
4858 Choices =>
4859 New_List (New_Occurrence_Of (Discriminant, Loc)),
4861 Expression =>
4862 New_Copy_Tree (
4863 Get_Discriminant_Value (
4864 Discriminant,
4865 Typ,
4866 Discriminant_Constraint (Typ))));
4868 if No (First_Comp) then
4869 Prepend_To (Component_Associations (N), New_Comp);
4870 else
4871 Insert_After (First_Comp, New_Comp);
4872 end if;
4874 First_Comp := New_Comp;
4875 Next_Stored_Discriminant (Discriminant);
4876 end loop;
4877 end Prepend_Stored_Values;
4879 -- Start of processing for Generate_Aggregate_For_Derived_Type
4881 begin
4882 -- Remove the associations for the discriminant of
4883 -- the derived type.
4885 First_Comp := First (Component_Associations (N));
4887 while Present (First_Comp) loop
4888 Comp := First_Comp;
4889 Next (First_Comp);
4891 if Ekind (Entity (First (Choices (Comp)))) =
4892 E_Discriminant
4893 then
4894 Remove (Comp);
4895 Num_Disc := Num_Disc + 1;
4896 end if;
4897 end loop;
4899 -- Insert stored discriminant associations in the correct
4900 -- order. If there are more stored discriminants than new
4901 -- discriminants, there is at least one new discriminant
4902 -- that constrains more than one of the stored discriminants.
4903 -- In this case we need to construct a proper subtype of
4904 -- the parent type, in order to supply values to all the
4905 -- components. Otherwise there is one-one correspondence
4906 -- between the constraints and the stored discriminants.
4908 First_Comp := Empty;
4910 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
4912 while Present (Discriminant) loop
4913 Num_Gird := Num_Gird + 1;
4914 Next_Stored_Discriminant (Discriminant);
4915 end loop;
4917 -- Case of more stored discriminants than new discriminants
4919 if Num_Gird > Num_Disc then
4921 -- Create a proper subtype of the parent type, which is
4922 -- the proper implementation type for the aggregate, and
4923 -- convert it to the intended target type.
4925 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
4927 while Present (Discriminant) loop
4928 New_Comp :=
4929 New_Copy_Tree (
4930 Get_Discriminant_Value (
4931 Discriminant,
4932 Typ,
4933 Discriminant_Constraint (Typ)));
4934 Append (New_Comp, Constraints);
4935 Next_Stored_Discriminant (Discriminant);
4936 end loop;
4938 Decl :=
4939 Make_Subtype_Declaration (Loc,
4940 Defining_Identifier =>
4941 Make_Defining_Identifier (Loc,
4942 New_Internal_Name ('T')),
4943 Subtype_Indication =>
4944 Make_Subtype_Indication (Loc,
4945 Subtype_Mark =>
4946 New_Occurrence_Of (Etype (Base_Type (Typ)), Loc),
4947 Constraint =>
4948 Make_Index_Or_Discriminant_Constraint
4949 (Loc, Constraints)));
4951 Insert_Action (N, Decl);
4952 Prepend_Stored_Values (Base_Type (Typ));
4954 Set_Etype (N, Defining_Identifier (Decl));
4955 Set_Analyzed (N);
4957 Rewrite (N, Unchecked_Convert_To (Typ, N));
4958 Analyze (N);
4960 -- Case where we do not have fewer new discriminants than
4961 -- stored discriminants, so in this case we can simply
4962 -- use the stored discriminants of the subtype.
4964 else
4965 Prepend_Stored_Values (Typ);
4966 end if;
4967 end Generate_Aggregate_For_Derived_Type;
4968 end if;
4970 if Is_Tagged_Type (Typ) then
4972 -- The tagged case, _parent and _tag component must be created
4974 -- Reset null_present unconditionally. tagged records always have
4975 -- at least one field (the tag or the parent)
4977 Set_Null_Record_Present (N, False);
4979 -- When the current aggregate comes from the expansion of an
4980 -- extension aggregate, the parent expr is replaced by an
4981 -- aggregate formed by selected components of this expr
4983 if Present (Parent_Expr)
4984 and then Is_Empty_List (Comps)
4985 then
4986 Comp := First_Entity (Typ);
4987 while Present (Comp) loop
4989 -- Skip all entities that aren't discriminants or components
4991 if Ekind (Comp) /= E_Discriminant
4992 and then Ekind (Comp) /= E_Component
4993 then
4994 null;
4996 -- Skip all expander-generated components
4998 elsif
4999 not Comes_From_Source (Original_Record_Component (Comp))
5000 then
5001 null;
5003 else
5004 New_Comp :=
5005 Make_Selected_Component (Loc,
5006 Prefix =>
5007 Unchecked_Convert_To (Typ,
5008 Duplicate_Subexpr (Parent_Expr, True)),
5010 Selector_Name => New_Occurrence_Of (Comp, Loc));
5012 Append_To (Comps,
5013 Make_Component_Association (Loc,
5014 Choices =>
5015 New_List (New_Occurrence_Of (Comp, Loc)),
5016 Expression =>
5017 New_Comp));
5019 Analyze_And_Resolve (New_Comp, Etype (Comp));
5020 end if;
5022 Next_Entity (Comp);
5023 end loop;
5024 end if;
5026 -- Compute the value for the Tag now, if the type is a root it
5027 -- will be included in the aggregate right away, otherwise it will
5028 -- be propagated to the parent aggregate
5030 if Present (Orig_Tag) then
5031 Tag_Value := Orig_Tag;
5032 elsif Java_VM then
5033 Tag_Value := Empty;
5034 else
5035 Tag_Value :=
5036 New_Occurrence_Of
5037 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc);
5038 end if;
5040 -- For a derived type, an aggregate for the parent is formed with
5041 -- all the inherited components.
5043 if Is_Derived_Type (Typ) then
5045 declare
5046 First_Comp : Node_Id;
5047 Parent_Comps : List_Id;
5048 Parent_Aggr : Node_Id;
5049 Parent_Name : Node_Id;
5051 begin
5052 -- Remove the inherited component association from the
5053 -- aggregate and store them in the parent aggregate
5055 First_Comp := First (Component_Associations (N));
5056 Parent_Comps := New_List;
5058 while Present (First_Comp)
5059 and then Scope (Original_Record_Component (
5060 Entity (First (Choices (First_Comp))))) /= Base_Typ
5061 loop
5062 Comp := First_Comp;
5063 Next (First_Comp);
5064 Remove (Comp);
5065 Append (Comp, Parent_Comps);
5066 end loop;
5068 Parent_Aggr := Make_Aggregate (Loc,
5069 Component_Associations => Parent_Comps);
5070 Set_Etype (Parent_Aggr, Etype (Base_Type (Typ)));
5072 -- Find the _parent component
5074 Comp := First_Component (Typ);
5075 while Chars (Comp) /= Name_uParent loop
5076 Comp := Next_Component (Comp);
5077 end loop;
5079 Parent_Name := New_Occurrence_Of (Comp, Loc);
5081 -- Insert the parent aggregate
5083 Prepend_To (Component_Associations (N),
5084 Make_Component_Association (Loc,
5085 Choices => New_List (Parent_Name),
5086 Expression => Parent_Aggr));
5088 -- Expand recursively the parent propagating the right Tag
5090 Expand_Record_Aggregate (
5091 Parent_Aggr, Tag_Value, Parent_Expr);
5092 end;
5094 -- For a root type, the tag component is added (unless compiling
5095 -- for the Java VM, where tags are implicit).
5097 elsif not Java_VM then
5098 declare
5099 Tag_Name : constant Node_Id :=
5100 New_Occurrence_Of
5101 (First_Tag_Component (Typ), Loc);
5102 Typ_Tag : constant Entity_Id := RTE (RE_Tag);
5103 Conv_Node : constant Node_Id :=
5104 Unchecked_Convert_To (Typ_Tag, Tag_Value);
5106 begin
5107 Set_Etype (Conv_Node, Typ_Tag);
5108 Prepend_To (Component_Associations (N),
5109 Make_Component_Association (Loc,
5110 Choices => New_List (Tag_Name),
5111 Expression => Conv_Node));
5112 end;
5113 end if;
5114 end if;
5115 end if;
5116 end Expand_Record_Aggregate;
5118 ----------------------------
5119 -- Has_Default_Init_Comps --
5120 ----------------------------
5122 function Has_Default_Init_Comps (N : Node_Id) return Boolean is
5123 Comps : constant List_Id := Component_Associations (N);
5124 C : Node_Id;
5125 Expr : Node_Id;
5126 begin
5127 pragma Assert (Nkind (N) = N_Aggregate
5128 or else Nkind (N) = N_Extension_Aggregate);
5130 if No (Comps) then
5131 return False;
5132 end if;
5134 -- Check if any direct component has default initialized components
5136 C := First (Comps);
5137 while Present (C) loop
5138 if Box_Present (C) then
5139 return True;
5140 end if;
5142 Next (C);
5143 end loop;
5145 -- Recursive call in case of aggregate expression
5147 C := First (Comps);
5148 while Present (C) loop
5149 Expr := Expression (C);
5151 if Present (Expr)
5152 and then (Nkind (Expr) = N_Aggregate
5153 or else Nkind (Expr) = N_Extension_Aggregate)
5154 and then Has_Default_Init_Comps (Expr)
5155 then
5156 return True;
5157 end if;
5159 Next (C);
5160 end loop;
5162 return False;
5163 end Has_Default_Init_Comps;
5165 --------------------------
5166 -- Is_Delayed_Aggregate --
5167 --------------------------
5169 function Is_Delayed_Aggregate (N : Node_Id) return Boolean is
5170 Node : Node_Id := N;
5171 Kind : Node_Kind := Nkind (Node);
5173 begin
5174 if Kind = N_Qualified_Expression then
5175 Node := Expression (Node);
5176 Kind := Nkind (Node);
5177 end if;
5179 if Kind /= N_Aggregate and then Kind /= N_Extension_Aggregate then
5180 return False;
5181 else
5182 return Expansion_Delayed (Node);
5183 end if;
5184 end Is_Delayed_Aggregate;
5186 --------------------
5187 -- Late_Expansion --
5188 --------------------
5190 function Late_Expansion
5191 (N : Node_Id;
5192 Typ : Entity_Id;
5193 Target : Node_Id;
5194 Flist : Node_Id := Empty;
5195 Obj : Entity_Id := Empty) return List_Id
5197 begin
5198 if Is_Record_Type (Etype (N)) then
5199 return Build_Record_Aggr_Code (N, Typ, Target, Flist, Obj);
5201 else pragma Assert (Is_Array_Type (Etype (N)));
5202 return
5203 Build_Array_Aggr_Code
5204 (N => N,
5205 Ctype => Component_Type (Etype (N)),
5206 Index => First_Index (Typ),
5207 Into => Target,
5208 Scalar_Comp => Is_Scalar_Type (Component_Type (Typ)),
5209 Indices => No_List,
5210 Flist => Flist);
5211 end if;
5212 end Late_Expansion;
5214 ----------------------------------
5215 -- Make_OK_Assignment_Statement --
5216 ----------------------------------
5218 function Make_OK_Assignment_Statement
5219 (Sloc : Source_Ptr;
5220 Name : Node_Id;
5221 Expression : Node_Id) return Node_Id
5223 begin
5224 Set_Assignment_OK (Name);
5225 return Make_Assignment_Statement (Sloc, Name, Expression);
5226 end Make_OK_Assignment_Statement;
5228 -----------------------
5229 -- Number_Of_Choices --
5230 -----------------------
5232 function Number_Of_Choices (N : Node_Id) return Nat is
5233 Assoc : Node_Id;
5234 Choice : Node_Id;
5236 Nb_Choices : Nat := 0;
5238 begin
5239 if Present (Expressions (N)) then
5240 return 0;
5241 end if;
5243 Assoc := First (Component_Associations (N));
5244 while Present (Assoc) loop
5246 Choice := First (Choices (Assoc));
5247 while Present (Choice) loop
5249 if Nkind (Choice) /= N_Others_Choice then
5250 Nb_Choices := Nb_Choices + 1;
5251 end if;
5253 Next (Choice);
5254 end loop;
5256 Next (Assoc);
5257 end loop;
5259 return Nb_Choices;
5260 end Number_Of_Choices;
5262 ------------------------------------
5263 -- Packed_Array_Aggregate_Handled --
5264 ------------------------------------
5266 -- The current version of this procedure will handle at compile time
5267 -- any array aggregate that meets these conditions:
5269 -- One dimensional, bit packed
5270 -- Underlying packed type is modular type
5271 -- Bounds are within 32-bit Int range
5272 -- All bounds and values are static
5274 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean is
5275 Loc : constant Source_Ptr := Sloc (N);
5276 Typ : constant Entity_Id := Etype (N);
5277 Ctyp : constant Entity_Id := Component_Type (Typ);
5279 Not_Handled : exception;
5280 -- Exception raised if this aggregate cannot be handled
5282 begin
5283 -- For now, handle only one dimensional bit packed arrays
5285 if not Is_Bit_Packed_Array (Typ)
5286 or else Number_Dimensions (Typ) > 1
5287 or else not Is_Modular_Integer_Type (Packed_Array_Type (Typ))
5288 then
5289 return False;
5290 end if;
5292 declare
5293 Csiz : constant Nat := UI_To_Int (Component_Size (Typ));
5295 Lo : Node_Id;
5296 Hi : Node_Id;
5297 -- Bounds of index type
5299 Lob : Uint;
5300 Hib : Uint;
5301 -- Values of bounds if compile time known
5303 function Get_Component_Val (N : Node_Id) return Uint;
5304 -- Given a expression value N of the component type Ctyp, returns
5305 -- A value of Csiz (component size) bits representing this value.
5306 -- If the value is non-static or any other reason exists why the
5307 -- value cannot be returned, then Not_Handled is raised.
5309 -----------------------
5310 -- Get_Component_Val --
5311 -----------------------
5313 function Get_Component_Val (N : Node_Id) return Uint is
5314 Val : Uint;
5316 begin
5317 -- We have to analyze the expression here before doing any further
5318 -- processing here. The analysis of such expressions is deferred
5319 -- till expansion to prevent some problems of premature analysis.
5321 Analyze_And_Resolve (N, Ctyp);
5323 -- Must have a compile time value. String literals have to
5324 -- be converted into temporaries as well, because they cannot
5325 -- easily be converted into their bit representation.
5327 if not Compile_Time_Known_Value (N)
5328 or else Nkind (N) = N_String_Literal
5329 then
5330 raise Not_Handled;
5331 end if;
5333 Val := Expr_Rep_Value (N);
5335 -- Adjust for bias, and strip proper number of bits
5337 if Has_Biased_Representation (Ctyp) then
5338 Val := Val - Expr_Value (Type_Low_Bound (Ctyp));
5339 end if;
5341 return Val mod Uint_2 ** Csiz;
5342 end Get_Component_Val;
5344 -- Here we know we have a one dimensional bit packed array
5346 begin
5347 Get_Index_Bounds (First_Index (Typ), Lo, Hi);
5349 -- Cannot do anything if bounds are dynamic
5351 if not Compile_Time_Known_Value (Lo)
5352 or else
5353 not Compile_Time_Known_Value (Hi)
5354 then
5355 return False;
5356 end if;
5358 -- Or are silly out of range of int bounds
5360 Lob := Expr_Value (Lo);
5361 Hib := Expr_Value (Hi);
5363 if not UI_Is_In_Int_Range (Lob)
5364 or else
5365 not UI_Is_In_Int_Range (Hib)
5366 then
5367 return False;
5368 end if;
5370 -- At this stage we have a suitable aggregate for handling
5371 -- at compile time (the only remaining checks, are that the
5372 -- values of expressions in the aggregate are compile time
5373 -- known (check performed by Get_Component_Val), and that
5374 -- any subtypes or ranges are statically known.
5376 -- If the aggregate is not fully positional at this stage,
5377 -- then convert it to positional form. Either this will fail,
5378 -- in which case we can do nothing, or it will succeed, in
5379 -- which case we have succeeded in handling the aggregate,
5380 -- or it will stay an aggregate, in which case we have failed
5381 -- to handle this case.
5383 if Present (Component_Associations (N)) then
5384 Convert_To_Positional
5385 (N, Max_Others_Replicate => 64, Handle_Bit_Packed => True);
5386 return Nkind (N) /= N_Aggregate;
5387 end if;
5389 -- Otherwise we are all positional, so convert to proper value
5391 declare
5392 Lov : constant Int := UI_To_Int (Lob);
5393 Hiv : constant Int := UI_To_Int (Hib);
5395 Len : constant Nat := Int'Max (0, Hiv - Lov + 1);
5396 -- The length of the array (number of elements)
5398 Aggregate_Val : Uint;
5399 -- Value of aggregate. The value is set in the low order
5400 -- bits of this value. For the little-endian case, the
5401 -- values are stored from low-order to high-order and
5402 -- for the big-endian case the values are stored from
5403 -- high-order to low-order. Note that gigi will take care
5404 -- of the conversions to left justify the value in the big
5405 -- endian case (because of left justified modular type
5406 -- processing), so we do not have to worry about that here.
5408 Lit : Node_Id;
5409 -- Integer literal for resulting constructed value
5411 Shift : Nat;
5412 -- Shift count from low order for next value
5414 Incr : Int;
5415 -- Shift increment for loop
5417 Expr : Node_Id;
5418 -- Next expression from positional parameters of aggregate
5420 begin
5421 -- For little endian, we fill up the low order bits of the
5422 -- target value. For big endian we fill up the high order
5423 -- bits of the target value (which is a left justified
5424 -- modular value).
5426 if Bytes_Big_Endian xor Debug_Flag_8 then
5427 Shift := Csiz * (Len - 1);
5428 Incr := -Csiz;
5429 else
5430 Shift := 0;
5431 Incr := +Csiz;
5432 end if;
5434 -- Loop to set the values
5436 if Len = 0 then
5437 Aggregate_Val := Uint_0;
5438 else
5439 Expr := First (Expressions (N));
5440 Aggregate_Val := Get_Component_Val (Expr) * Uint_2 ** Shift;
5442 for J in 2 .. Len loop
5443 Shift := Shift + Incr;
5444 Next (Expr);
5445 Aggregate_Val :=
5446 Aggregate_Val + Get_Component_Val (Expr) * Uint_2 ** Shift;
5447 end loop;
5448 end if;
5450 -- Now we can rewrite with the proper value
5452 Lit :=
5453 Make_Integer_Literal (Loc,
5454 Intval => Aggregate_Val);
5455 Set_Print_In_Hex (Lit);
5457 -- Construct the expression using this literal. Note that it is
5458 -- important to qualify the literal with its proper modular type
5459 -- since universal integer does not have the required range and
5460 -- also this is a left justified modular type, which is important
5461 -- in the big-endian case.
5463 Rewrite (N,
5464 Unchecked_Convert_To (Typ,
5465 Make_Qualified_Expression (Loc,
5466 Subtype_Mark =>
5467 New_Occurrence_Of (Packed_Array_Type (Typ), Loc),
5468 Expression => Lit)));
5470 Analyze_And_Resolve (N, Typ);
5471 return True;
5472 end;
5473 end;
5475 exception
5476 when Not_Handled =>
5477 return False;
5478 end Packed_Array_Aggregate_Handled;
5480 ----------------------------
5481 -- Has_Mutable_Components --
5482 ----------------------------
5484 function Has_Mutable_Components (Typ : Entity_Id) return Boolean is
5485 Comp : Entity_Id;
5487 begin
5488 Comp := First_Component (Typ);
5490 while Present (Comp) loop
5491 if Is_Record_Type (Etype (Comp))
5492 and then Has_Discriminants (Etype (Comp))
5493 and then not Is_Constrained (Etype (Comp))
5494 then
5495 return True;
5496 end if;
5498 Next_Component (Comp);
5499 end loop;
5501 return False;
5502 end Has_Mutable_Components;
5504 ------------------------------
5505 -- Initialize_Discriminants --
5506 ------------------------------
5508 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id) is
5509 Loc : constant Source_Ptr := Sloc (N);
5510 Bas : constant Entity_Id := Base_Type (Typ);
5511 Par : constant Entity_Id := Etype (Bas);
5512 Decl : constant Node_Id := Parent (Par);
5513 Ref : Node_Id;
5515 begin
5516 if Is_Tagged_Type (Bas)
5517 and then Is_Derived_Type (Bas)
5518 and then Has_Discriminants (Par)
5519 and then Has_Discriminants (Bas)
5520 and then Number_Discriminants (Bas) /= Number_Discriminants (Par)
5521 and then Nkind (Decl) = N_Full_Type_Declaration
5522 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
5523 and then Present
5524 (Variant_Part (Component_List (Type_Definition (Decl))))
5525 and then Nkind (N) /= N_Extension_Aggregate
5526 then
5528 -- Call init proc to set discriminants.
5529 -- There should eventually be a special procedure for this ???
5531 Ref := New_Reference_To (Defining_Identifier (N), Loc);
5532 Insert_Actions_After (N,
5533 Build_Initialization_Call (Sloc (N), Ref, Typ));
5534 end if;
5535 end Initialize_Discriminants;
5537 ----------------
5538 -- Must_Slide --
5539 ----------------
5541 function Must_Slide
5542 (Obj_Type : Entity_Id;
5543 Typ : Entity_Id) return Boolean
5545 L1, L2, H1, H2 : Node_Id;
5546 begin
5547 -- No sliding if the type of the object is not established yet, if
5548 -- it is an unconstrained type whose actual subtype comes from the
5549 -- aggregate, or if the two types are identical.
5551 if not Is_Array_Type (Obj_Type) then
5552 return False;
5554 elsif not Is_Constrained (Obj_Type) then
5555 return False;
5557 elsif Typ = Obj_Type then
5558 return False;
5560 else
5561 -- Sliding can only occur along the first dimension
5563 Get_Index_Bounds (First_Index (Typ), L1, H1);
5564 Get_Index_Bounds (First_Index (Obj_Type), L2, H2);
5566 if not Is_Static_Expression (L1)
5567 or else not Is_Static_Expression (L2)
5568 or else not Is_Static_Expression (H1)
5569 or else not Is_Static_Expression (H2)
5570 then
5571 return False;
5572 else
5573 return Expr_Value (L1) /= Expr_Value (L2)
5574 or else Expr_Value (H1) /= Expr_Value (H2);
5575 end if;
5576 end if;
5577 end Must_Slide;
5579 ---------------------------
5580 -- Safe_Slice_Assignment --
5581 ---------------------------
5583 function Safe_Slice_Assignment (N : Node_Id) return Boolean is
5584 Loc : constant Source_Ptr := Sloc (Parent (N));
5585 Pref : constant Node_Id := Prefix (Name (Parent (N)));
5586 Range_Node : constant Node_Id := Discrete_Range (Name (Parent (N)));
5587 Expr : Node_Id;
5588 L_J : Entity_Id;
5589 L_Iter : Node_Id;
5590 L_Body : Node_Id;
5591 Stat : Node_Id;
5593 begin
5594 -- Generate: for J in Range loop Pref (J) := Expr; end loop;
5596 if Comes_From_Source (N)
5597 and then No (Expressions (N))
5598 and then Nkind (First (Choices (First (Component_Associations (N)))))
5599 = N_Others_Choice
5600 then
5601 Expr :=
5602 Expression (First (Component_Associations (N)));
5603 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
5605 L_Iter :=
5606 Make_Iteration_Scheme (Loc,
5607 Loop_Parameter_Specification =>
5608 Make_Loop_Parameter_Specification
5609 (Loc,
5610 Defining_Identifier => L_J,
5611 Discrete_Subtype_Definition => Relocate_Node (Range_Node)));
5613 L_Body :=
5614 Make_Assignment_Statement (Loc,
5615 Name =>
5616 Make_Indexed_Component (Loc,
5617 Prefix => Relocate_Node (Pref),
5618 Expressions => New_List (New_Occurrence_Of (L_J, Loc))),
5619 Expression => Relocate_Node (Expr));
5621 -- Construct the final loop
5623 Stat :=
5624 Make_Implicit_Loop_Statement
5625 (Node => Parent (N),
5626 Identifier => Empty,
5627 Iteration_Scheme => L_Iter,
5628 Statements => New_List (L_Body));
5630 -- Set type of aggregate to be type of lhs in assignment,
5631 -- to suppress redundant length checks.
5633 Set_Etype (N, Etype (Name (Parent (N))));
5635 Rewrite (Parent (N), Stat);
5636 Analyze (Parent (N));
5637 return True;
5639 else
5640 return False;
5641 end if;
5642 end Safe_Slice_Assignment;
5644 ---------------------
5645 -- Sort_Case_Table --
5646 ---------------------
5648 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
5649 L : constant Int := Case_Table'First;
5650 U : constant Int := Case_Table'Last;
5651 K : Int;
5652 J : Int;
5653 T : Case_Bounds;
5655 begin
5656 K := L;
5658 while K /= U loop
5659 T := Case_Table (K + 1);
5660 J := K + 1;
5662 while J /= L
5663 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
5664 Expr_Value (T.Choice_Lo)
5665 loop
5666 Case_Table (J) := Case_Table (J - 1);
5667 J := J - 1;
5668 end loop;
5670 Case_Table (J) := T;
5671 K := K + 1;
5672 end loop;
5673 end Sort_Case_Table;
5675 end Exp_Aggr;