1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Expander; use Expander;
32 with Exp_Util; use Exp_Util;
33 with Exp_Ch3; use Exp_Ch3;
34 with Exp_Ch7; use Exp_Ch7;
35 with Exp_Ch9; use Exp_Ch9;
36 with Exp_Tss; use Exp_Tss;
37 with Freeze; use Freeze;
38 with Itypes; use Itypes;
40 with Namet; use Namet;
41 with Nmake; use Nmake;
42 with Nlists; use Nlists;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
46 with Rtsfind; use Rtsfind;
47 with Ttypes; use Ttypes;
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 Targparm; use Targparm;
57 with Tbuild; use Tbuild;
58 with Uintp; use Uintp;
60 package body Exp_Aggr is
62 type Case_Bounds is record
65 Choice_Node : Node_Id;
68 type Case_Table_Type is array (Nat range <>) of Case_Bounds;
69 -- Table type used by Check_Case_Choices procedure
72 (Obj_Type : Entity_Id;
73 Typ : Entity_Id) return Boolean;
74 -- A static array aggregate in an object declaration can in most cases be
75 -- expanded in place. The one exception is when the aggregate is given
76 -- with component associations that specify different bounds from those of
77 -- the type definition in the object declaration. In this pathological
78 -- case the aggregate must slide, and we must introduce an intermediate
79 -- temporary to hold it.
81 -- The same holds in an assignment to one-dimensional array of arrays,
82 -- when a component may be given with bounds that differ from those of the
85 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
86 -- Sort the Case Table using the Lower Bound of each Choice as the key.
87 -- A simple insertion sort is used since the number of choices in a case
88 -- statement of variant part will usually be small and probably in near
91 function Has_Default_Init_Comps (N : Node_Id) return Boolean;
92 -- N is an aggregate (record or array). Checks the presence of default
93 -- initialization (<>) in any component (Ada 2005: AI-287)
95 function Is_Static_Dispatch_Table_Aggregate (N : Node_Id) return Boolean;
96 -- Returns true if N is an aggregate used to initialize the components
97 -- of an statically allocated dispatch table.
99 ------------------------------------------------------
100 -- Local subprograms for Record Aggregate Expansion --
101 ------------------------------------------------------
103 procedure Expand_Record_Aggregate
105 Orig_Tag : Node_Id := Empty;
106 Parent_Expr : Node_Id := Empty);
107 -- This is the top level procedure for record aggregate expansion.
108 -- Expansion for record aggregates needs expand aggregates for tagged
109 -- record types. Specifically Expand_Record_Aggregate adds the Tag
110 -- field in front of the Component_Association list that was created
111 -- during resolution by Resolve_Record_Aggregate.
113 -- N is the record aggregate node.
114 -- Orig_Tag is the value of the Tag that has to be provided for this
115 -- specific aggregate. It carries the tag corresponding to the type
116 -- of the outermost aggregate during the recursive expansion
117 -- Parent_Expr is the ancestor part of the original extension
120 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id);
121 -- N is an N_Aggregate or an N_Extension_Aggregate. Typ is the type of the
122 -- aggregate (which can only be a record type, this procedure is only used
123 -- for record types). Transform the given aggregate into a sequence of
124 -- assignments performed component by component.
126 function Build_Record_Aggr_Code
130 Flist : Node_Id := Empty;
131 Obj : Entity_Id := Empty;
132 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id;
133 -- N is an N_Aggregate or an N_Extension_Aggregate. Typ is the type of the
134 -- aggregate. Target is an expression containing the location on which the
135 -- component by component assignments will take place. Returns the list of
136 -- assignments plus all other adjustments needed for tagged and controlled
137 -- types. Flist is an expression representing the finalization list on
138 -- which to attach the controlled components if any. Obj is present in the
139 -- object declaration and dynamic allocation cases, it contains an entity
140 -- that allows to know if the value being created needs to be attached to
141 -- the final list in case of pragma Finalize_Storage_Only.
144 -- The meaning of the Obj formal is extremely unclear. *What* entity
145 -- should be passed? For the object declaration case we may guess that
146 -- this is the object being declared, but what about the allocator case?
148 -- Is_Limited_Ancestor_Expansion indicates that the function has been
149 -- called recursively to expand the limited ancestor to avoid copying it.
151 function Has_Mutable_Components (Typ : Entity_Id) return Boolean;
152 -- Return true if one of the component is of a discriminated type with
153 -- defaults. An aggregate for a type with mutable components must be
154 -- expanded into individual assignments.
156 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id);
157 -- If the type of the aggregate is a type extension with renamed discrimi-
158 -- nants, we must initialize the hidden discriminants of the parent.
159 -- Otherwise, the target object must not be initialized. The discriminants
160 -- are initialized by calling the initialization procedure for the type.
161 -- This is incorrect if the initialization of other components has any
162 -- side effects. We restrict this call to the case where the parent type
163 -- has a variant part, because this is the only case where the hidden
164 -- discriminants are accessed, namely when calling discriminant checking
165 -- functions of the parent type, and when applying a stream attribute to
166 -- an object of the derived type.
168 -----------------------------------------------------
169 -- Local Subprograms for Array Aggregate Expansion --
170 -----------------------------------------------------
172 function Aggr_Size_OK (Typ : Entity_Id) return Boolean;
173 -- Very large static aggregates present problems to the back-end, and
174 -- are transformed into assignments and loops. This function verifies
175 -- that the total number of components of an aggregate is acceptable
176 -- for transformation into a purely positional static form. It is called
177 -- prior to calling Flatten.
179 procedure Convert_Array_Aggr_In_Allocator
183 -- If the aggregate appears within an allocator and can be expanded in
184 -- place, this routine generates the individual assignments to components
185 -- of the designated object. This is an optimization over the general
186 -- case, where a temporary is first created on the stack and then used to
187 -- construct the allocated object on the heap.
189 procedure Convert_To_Positional
191 Max_Others_Replicate : Nat := 5;
192 Handle_Bit_Packed : Boolean := False);
193 -- If possible, convert named notation to positional notation. This
194 -- conversion is possible only in some static cases. If the conversion is
195 -- possible, then N is rewritten with the analyzed converted aggregate.
196 -- The parameter Max_Others_Replicate controls the maximum number of
197 -- values corresponding to an others choice that will be converted to
198 -- positional notation (the default of 5 is the normal limit, and reflects
199 -- the fact that normally the loop is better than a lot of separate
200 -- assignments). Note that this limit gets overridden in any case if
201 -- either of the restrictions No_Elaboration_Code or No_Implicit_Loops is
202 -- set. The parameter Handle_Bit_Packed is usually set False (since we do
203 -- not expect the back end to handle bit packed arrays, so the normal case
204 -- of conversion is pointless), but in the special case of a call from
205 -- Packed_Array_Aggregate_Handled, we set this parameter to True, since
206 -- these are cases we handle in there.
208 procedure Expand_Array_Aggregate (N : Node_Id);
209 -- This is the top-level routine to perform array aggregate expansion.
210 -- N is the N_Aggregate node to be expanded.
212 function Backend_Processing_Possible (N : Node_Id) return Boolean;
213 -- This function checks if array aggregate N can be processed directly
214 -- by Gigi. If this is the case True is returned.
216 function Build_Array_Aggr_Code
221 Scalar_Comp : Boolean;
222 Indices : List_Id := No_List;
223 Flist : Node_Id := Empty) return List_Id;
224 -- This recursive routine returns a list of statements containing the
225 -- loops and assignments that are needed for the expansion of the array
228 -- N is the (sub-)aggregate node to be expanded into code. This node
229 -- has been fully analyzed, and its Etype is properly set.
231 -- Index is the index node corresponding to the array sub-aggregate N.
233 -- Into is the target expression into which we are copying the aggregate.
234 -- Note that this node may not have been analyzed yet, and so the Etype
235 -- field may not be set.
237 -- Scalar_Comp is True if the component type of the aggregate is scalar.
239 -- Indices is the current list of expressions used to index the
240 -- object we are writing into.
242 -- Flist is an expression representing the finalization list on which
243 -- to attach the controlled components if any.
245 function Number_Of_Choices (N : Node_Id) return Nat;
246 -- Returns the number of discrete choices (not including the others choice
247 -- if present) contained in (sub-)aggregate N.
249 function Late_Expansion
253 Flist : Node_Id := Empty;
254 Obj : Entity_Id := Empty) return List_Id;
255 -- N is a nested (record or array) aggregate that has been marked with
256 -- 'Delay_Expansion'. Typ is the expected type of the aggregate and Target
257 -- is a (duplicable) expression that will hold the result of the aggregate
258 -- expansion. Flist is the finalization list to be used to attach
259 -- controlled components. 'Obj' when non empty, carries the original
260 -- object being initialized in order to know if it needs to be attached to
261 -- the previous parameter which may not be the case in the case where
262 -- Finalize_Storage_Only is set. Basically this procedure is used to
263 -- implement top-down expansions of nested aggregates. This is necessary
264 -- for avoiding temporaries at each level as well as for propagating the
265 -- right internal finalization list.
267 function Make_OK_Assignment_Statement
270 Expression : Node_Id) return Node_Id;
271 -- This is like Make_Assignment_Statement, except that Assignment_OK
272 -- is set in the left operand. All assignments built by this unit
273 -- use this routine. This is needed to deal with assignments to
274 -- initialized constants that are done in place.
276 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean;
277 -- Given an array aggregate, this function handles the case of a packed
278 -- array aggregate with all constant values, where the aggregate can be
279 -- evaluated at compile time. If this is possible, then N is rewritten
280 -- to be its proper compile time value with all the components properly
281 -- assembled. The expression is analyzed and resolved and True is
282 -- returned. If this transformation is not possible, N is unchanged
283 -- and False is returned
285 function Safe_Slice_Assignment (N : Node_Id) return Boolean;
286 -- If a slice assignment has an aggregate with a single others_choice,
287 -- the assignment can be done in place even if bounds are not static,
288 -- by converting it into a loop over the discrete range of the slice.
294 function Aggr_Size_OK (Typ : Entity_Id) return Boolean is
302 -- The following constant determines the maximum size of an
303 -- array aggregate produced by converting named to positional
304 -- notation (e.g. from others clauses). This avoids running
305 -- away with attempts to convert huge aggregates, which hit
306 -- memory limits in the backend.
308 -- The normal limit is 5000, but we increase this limit to
309 -- 2**24 (about 16 million) if Restrictions (No_Elaboration_Code)
310 -- or Restrictions (No_Implicit_Loops) is specified, since in
311 -- either case, we are at risk of declaring the program illegal
312 -- because of this limit.
314 Max_Aggr_Size : constant Nat :=
315 5000 + (2 ** 24 - 5000) *
317 (Restriction_Active (No_Elaboration_Code)
319 Restriction_Active (No_Implicit_Loops));
321 function Component_Count (T : Entity_Id) return Int;
322 -- The limit is applied to the total number of components that the
323 -- aggregate will have, which is the number of static expressions
324 -- that will appear in the flattened array. This requires a recursive
325 -- computation of the the number of scalar components of the structure.
327 ---------------------
328 -- Component_Count --
329 ---------------------
331 function Component_Count (T : Entity_Id) return Int is
336 if Is_Scalar_Type (T) then
339 elsif Is_Record_Type (T) then
340 Comp := First_Component (T);
341 while Present (Comp) loop
342 Res := Res + Component_Count (Etype (Comp));
343 Next_Component (Comp);
348 elsif Is_Array_Type (T) then
350 Lo : constant Node_Id :=
351 Type_Low_Bound (Etype (First_Index (T)));
352 Hi : constant Node_Id :=
353 Type_High_Bound (Etype (First_Index (T)));
355 Siz : constant Int := Component_Count (Component_Type (T));
358 if not Compile_Time_Known_Value (Lo)
359 or else not Compile_Time_Known_Value (Hi)
364 Siz * UI_To_Int (Expr_Value (Hi) - Expr_Value (Lo) + 1);
369 -- Can only be a null for an access type
375 -- Start of processing for Aggr_Size_OK
378 Siz := Component_Count (Component_Type (Typ));
380 Indx := First_Index (Typ);
381 while Present (Indx) loop
382 Lo := Type_Low_Bound (Etype (Indx));
383 Hi := Type_High_Bound (Etype (Indx));
385 -- Bounds need to be known at compile time
387 if not Compile_Time_Known_Value (Lo)
388 or else not Compile_Time_Known_Value (Hi)
393 Lov := Expr_Value (Lo);
394 Hiv := Expr_Value (Hi);
396 -- A flat array is always safe
403 Rng : constant Uint := Hiv - Lov + 1;
406 -- Check if size is too large
408 if not UI_Is_In_Int_Range (Rng) then
412 Siz := Siz * UI_To_Int (Rng);
416 or else Siz > Max_Aggr_Size
421 -- Bounds must be in integer range, for later array construction
423 if not UI_Is_In_Int_Range (Lov)
425 not UI_Is_In_Int_Range (Hiv)
436 ---------------------------------
437 -- Backend_Processing_Possible --
438 ---------------------------------
440 -- Backend processing by Gigi/gcc is possible only if all the following
441 -- conditions are met:
443 -- 1. N is fully positional
445 -- 2. N is not a bit-packed array aggregate;
447 -- 3. The size of N's array type must be known at compile time. Note
448 -- that this implies that the component size is also known
450 -- 4. The array type of N does not follow the Fortran layout convention
451 -- or if it does it must be 1 dimensional.
453 -- 5. The array component type may not be tagged (which could necessitate
454 -- reassignment of proper tags).
456 -- 6. The array component type must not have unaligned bit components
458 -- 7. None of the components of the aggregate may be bit unaligned
461 -- 8. There cannot be delayed components, since we do not know enough
462 -- at this stage to know if back end processing is possible.
464 -- 9. There cannot be any discriminated record components, since the
465 -- back end cannot handle this complex case.
467 function Backend_Processing_Possible (N : Node_Id) return Boolean is
468 Typ : constant Entity_Id := Etype (N);
469 -- Typ is the correct constrained array subtype of the aggregate
471 function Component_Check (N : Node_Id; Index : Node_Id) return Boolean;
472 -- This routine checks components of aggregate N, enforcing checks
473 -- 1, 7, 8, and 9. In the multi-dimensional case, these checks are
474 -- performed on subaggregates. The Index value is the current index
475 -- being checked in the multi-dimensional case.
477 ---------------------
478 -- Component_Check --
479 ---------------------
481 function Component_Check (N : Node_Id; Index : Node_Id) return Boolean is
485 -- Checks 1: (no component associations)
487 if Present (Component_Associations (N)) then
491 -- Checks on components
493 -- Recurse to check subaggregates, which may appear in qualified
494 -- expressions. If delayed, the front-end will have to expand.
495 -- If the component is a discriminated record, treat as non-static,
496 -- as the back-end cannot handle this properly.
498 Expr := First (Expressions (N));
499 while Present (Expr) loop
501 -- Checks 8: (no delayed components)
503 if Is_Delayed_Aggregate (Expr) then
507 -- Checks 9: (no discriminated records)
509 if Present (Etype (Expr))
510 and then Is_Record_Type (Etype (Expr))
511 and then Has_Discriminants (Etype (Expr))
516 -- Checks 7. Component must not be bit aligned component
518 if Possible_Bit_Aligned_Component (Expr) then
522 -- Recursion to following indexes for multiple dimension case
524 if Present (Next_Index (Index))
525 and then not Component_Check (Expr, Next_Index (Index))
530 -- All checks for that component finished, on to next
538 -- Start of processing for Backend_Processing_Possible
541 -- Checks 2 (array must not be bit packed)
543 if Is_Bit_Packed_Array (Typ) then
547 -- Checks 4 (array must not be multi-dimensional Fortran case)
549 if Convention (Typ) = Convention_Fortran
550 and then Number_Dimensions (Typ) > 1
555 -- Checks 3 (size of array must be known at compile time)
557 if not Size_Known_At_Compile_Time (Typ) then
561 -- Checks on components
563 if not Component_Check (N, First_Index (Typ)) then
567 -- Checks 5 (if the component type is tagged, then we may need to do
568 -- tag adjustments. Perhaps this should be refined to check for any
569 -- component associations that actually need tag adjustment, similar
570 -- to the test in Component_Not_OK_For_Backend for record aggregates
571 -- with tagged components, but not clear whether it's worthwhile ???;
572 -- in the case of the JVM, object tags are handled implicitly)
574 if Is_Tagged_Type (Component_Type (Typ)) and then VM_Target = No_VM then
578 -- Checks 6 (component type must not have bit aligned components)
580 if Type_May_Have_Bit_Aligned_Components (Component_Type (Typ)) then
584 -- Backend processing is possible
586 Set_Size_Known_At_Compile_Time (Etype (N), True);
588 end Backend_Processing_Possible;
590 ---------------------------
591 -- Build_Array_Aggr_Code --
592 ---------------------------
594 -- The code that we generate from a one dimensional aggregate is
596 -- 1. If the sub-aggregate contains discrete choices we
598 -- (a) Sort the discrete choices
600 -- (b) Otherwise for each discrete choice that specifies a range we
601 -- emit a loop. If a range specifies a maximum of three values, or
602 -- we are dealing with an expression we emit a sequence of
603 -- assignments instead of a loop.
605 -- (c) Generate the remaining loops to cover the others choice if any
607 -- 2. If the aggregate contains positional elements we
609 -- (a) translate the positional elements in a series of assignments
611 -- (b) Generate a final loop to cover the others choice if any.
612 -- Note that this final loop has to be a while loop since the case
614 -- L : Integer := Integer'Last;
615 -- H : Integer := Integer'Last;
616 -- A : array (L .. H) := (1, others =>0);
618 -- cannot be handled by a for loop. Thus for the following
620 -- array (L .. H) := (.. positional elements.., others =>E);
622 -- we always generate something like:
624 -- J : Index_Type := Index_Of_Last_Positional_Element;
626 -- J := Index_Base'Succ (J)
630 function Build_Array_Aggr_Code
635 Scalar_Comp : Boolean;
636 Indices : List_Id := No_List;
637 Flist : Node_Id := Empty) return List_Id
639 Loc : constant Source_Ptr := Sloc (N);
640 Index_Base : constant Entity_Id := Base_Type (Etype (Index));
641 Index_Base_L : constant Node_Id := Type_Low_Bound (Index_Base);
642 Index_Base_H : constant Node_Id := Type_High_Bound (Index_Base);
644 function Add (Val : Int; To : Node_Id) return Node_Id;
645 -- Returns an expression where Val is added to expression To, unless
646 -- To+Val is provably out of To's base type range. To must be an
647 -- already analyzed expression.
649 function Empty_Range (L, H : Node_Id) return Boolean;
650 -- Returns True if the range defined by L .. H is certainly empty
652 function Equal (L, H : Node_Id) return Boolean;
653 -- Returns True if L = H for sure
655 function Index_Base_Name return Node_Id;
656 -- Returns a new reference to the index type name
658 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id;
659 -- Ind must be a side-effect free expression. If the input aggregate
660 -- N to Build_Loop contains no sub-aggregates, then this function
661 -- returns the assignment statement:
663 -- Into (Indices, Ind) := Expr;
665 -- Otherwise we call Build_Code recursively
667 -- Ada 2005 (AI-287): In case of default initialized component, Expr
668 -- is empty and we generate a call to the corresponding IP subprogram.
670 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id;
671 -- Nodes L and H must be side-effect free expressions.
672 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
673 -- This routine returns the for loop statement
675 -- for J in Index_Base'(L) .. Index_Base'(H) loop
676 -- Into (Indices, J) := Expr;
679 -- Otherwise we call Build_Code recursively.
680 -- As an optimization if the loop covers 3 or less scalar elements we
681 -- generate a sequence of assignments.
683 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id;
684 -- Nodes L and H must be side-effect free expressions.
685 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
686 -- This routine returns the while loop statement
688 -- J : Index_Base := L;
690 -- J := Index_Base'Succ (J);
691 -- Into (Indices, J) := Expr;
694 -- Otherwise we call Build_Code recursively
696 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean;
697 function Local_Expr_Value (E : Node_Id) return Uint;
698 -- These two Local routines are used to replace the corresponding ones
699 -- in sem_eval because while processing the bounds of an aggregate with
700 -- discrete choices whose index type is an enumeration, we build static
701 -- expressions not recognized by Compile_Time_Known_Value as such since
702 -- they have not yet been analyzed and resolved. All the expressions in
703 -- question are things like Index_Base_Name'Val (Const) which we can
704 -- easily recognize as being constant.
710 function Add (Val : Int; To : Node_Id) return Node_Id is
715 U_Val : constant Uint := UI_From_Int (Val);
718 -- Note: do not try to optimize the case of Val = 0, because
719 -- we need to build a new node with the proper Sloc value anyway.
721 -- First test if we can do constant folding
723 if Local_Compile_Time_Known_Value (To) then
724 U_To := Local_Expr_Value (To) + Val;
726 -- Determine if our constant is outside the range of the index.
727 -- If so return an Empty node. This empty node will be caught
728 -- by Empty_Range below.
730 if Compile_Time_Known_Value (Index_Base_L)
731 and then U_To < Expr_Value (Index_Base_L)
735 elsif Compile_Time_Known_Value (Index_Base_H)
736 and then U_To > Expr_Value (Index_Base_H)
741 Expr_Pos := Make_Integer_Literal (Loc, U_To);
742 Set_Is_Static_Expression (Expr_Pos);
744 if not Is_Enumeration_Type (Index_Base) then
747 -- If we are dealing with enumeration return
748 -- Index_Base'Val (Expr_Pos)
752 Make_Attribute_Reference
754 Prefix => Index_Base_Name,
755 Attribute_Name => Name_Val,
756 Expressions => New_List (Expr_Pos));
762 -- If we are here no constant folding possible
764 if not Is_Enumeration_Type (Index_Base) then
767 Left_Opnd => Duplicate_Subexpr (To),
768 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
770 -- If we are dealing with enumeration return
771 -- Index_Base'Val (Index_Base'Pos (To) + Val)
775 Make_Attribute_Reference
777 Prefix => Index_Base_Name,
778 Attribute_Name => Name_Pos,
779 Expressions => New_List (Duplicate_Subexpr (To)));
784 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
787 Make_Attribute_Reference
789 Prefix => Index_Base_Name,
790 Attribute_Name => Name_Val,
791 Expressions => New_List (Expr_Pos));
801 function Empty_Range (L, H : Node_Id) return Boolean is
802 Is_Empty : Boolean := False;
807 -- First check if L or H were already detected as overflowing the
808 -- index base range type by function Add above. If this is so Add
809 -- returns the empty node.
811 if No (L) or else No (H) then
818 -- L > H range is empty
824 -- B_L > H range must be empty
830 -- L > B_H range must be empty
834 High := Index_Base_H;
837 if Local_Compile_Time_Known_Value (Low)
838 and then Local_Compile_Time_Known_Value (High)
841 UI_Gt (Local_Expr_Value (Low), Local_Expr_Value (High));
854 function Equal (L, H : Node_Id) return Boolean is
859 elsif Local_Compile_Time_Known_Value (L)
860 and then Local_Compile_Time_Known_Value (H)
862 return UI_Eq (Local_Expr_Value (L), Local_Expr_Value (H));
872 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id is
873 L : constant List_Id := New_List;
877 New_Indices : List_Id;
878 Indexed_Comp : Node_Id;
880 Comp_Type : Entity_Id := Empty;
882 function Add_Loop_Actions (Lis : List_Id) return List_Id;
883 -- Collect insert_actions generated in the construction of a
884 -- loop, and prepend them to the sequence of assignments to
885 -- complete the eventual body of the loop.
887 ----------------------
888 -- Add_Loop_Actions --
889 ----------------------
891 function Add_Loop_Actions (Lis : List_Id) return List_Id is
895 -- Ada 2005 (AI-287): Do nothing else in case of default
896 -- initialized component.
901 elsif Nkind (Parent (Expr)) = N_Component_Association
902 and then Present (Loop_Actions (Parent (Expr)))
904 Append_List (Lis, Loop_Actions (Parent (Expr)));
905 Res := Loop_Actions (Parent (Expr));
906 Set_Loop_Actions (Parent (Expr), No_List);
912 end Add_Loop_Actions;
914 -- Start of processing for Gen_Assign
918 New_Indices := New_List;
920 New_Indices := New_Copy_List_Tree (Indices);
923 Append_To (New_Indices, Ind);
925 if Present (Flist) then
926 F := New_Copy_Tree (Flist);
928 elsif Present (Etype (N)) and then Controlled_Type (Etype (N)) then
929 if Is_Entity_Name (Into)
930 and then Present (Scope (Entity (Into)))
932 F := Find_Final_List (Scope (Entity (Into)));
934 F := Find_Final_List (Current_Scope);
940 if Present (Next_Index (Index)) then
943 Build_Array_Aggr_Code
946 Index => Next_Index (Index),
948 Scalar_Comp => Scalar_Comp,
949 Indices => New_Indices,
953 -- If we get here then we are at a bottom-level (sub-)aggregate
957 (Make_Indexed_Component (Loc,
958 Prefix => New_Copy_Tree (Into),
959 Expressions => New_Indices));
961 Set_Assignment_OK (Indexed_Comp);
963 -- Ada 2005 (AI-287): In case of default initialized component, Expr
964 -- is not present (and therefore we also initialize Expr_Q to empty).
968 elsif Nkind (Expr) = N_Qualified_Expression then
969 Expr_Q := Expression (Expr);
974 if Present (Etype (N))
975 and then Etype (N) /= Any_Composite
977 Comp_Type := Component_Type (Etype (N));
978 pragma Assert (Comp_Type = Ctype); -- AI-287
980 elsif Present (Next (First (New_Indices))) then
982 -- Ada 2005 (AI-287): Do nothing in case of default initialized
983 -- component because we have received the component type in
984 -- the formal parameter Ctype.
986 -- ??? Some assert pragmas have been added to check if this new
987 -- formal can be used to replace this code in all cases.
989 if Present (Expr) then
991 -- This is a multidimensional array. Recover the component
992 -- type from the outermost aggregate, because subaggregates
993 -- do not have an assigned type.
1000 while Present (P) loop
1001 if Nkind (P) = N_Aggregate
1002 and then Present (Etype (P))
1004 Comp_Type := Component_Type (Etype (P));
1012 pragma Assert (Comp_Type = Ctype); -- AI-287
1017 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
1018 -- default initialized components (otherwise Expr_Q is not present).
1021 and then (Nkind (Expr_Q) = N_Aggregate
1022 or else Nkind (Expr_Q) = N_Extension_Aggregate)
1024 -- At this stage the Expression may not have been
1025 -- analyzed yet because the array aggregate code has not
1026 -- been updated to use the Expansion_Delayed flag and
1027 -- avoid analysis altogether to solve the same problem
1028 -- (see Resolve_Aggr_Expr). So let us do the analysis of
1029 -- non-array aggregates now in order to get the value of
1030 -- Expansion_Delayed flag for the inner aggregate ???
1032 if Present (Comp_Type) and then not Is_Array_Type (Comp_Type) then
1033 Analyze_And_Resolve (Expr_Q, Comp_Type);
1036 if Is_Delayed_Aggregate (Expr_Q) then
1038 -- This is either a subaggregate of a multidimentional array,
1039 -- or a component of an array type whose component type is
1040 -- also an array. In the latter case, the expression may have
1041 -- component associations that provide different bounds from
1042 -- those of the component type, and sliding must occur. Instead
1043 -- of decomposing the current aggregate assignment, force the
1044 -- re-analysis of the assignment, so that a temporary will be
1045 -- generated in the usual fashion, and sliding will take place.
1047 if Nkind (Parent (N)) = N_Assignment_Statement
1048 and then Is_Array_Type (Comp_Type)
1049 and then Present (Component_Associations (Expr_Q))
1050 and then Must_Slide (Comp_Type, Etype (Expr_Q))
1052 Set_Expansion_Delayed (Expr_Q, False);
1053 Set_Analyzed (Expr_Q, False);
1059 Expr_Q, Etype (Expr_Q), Indexed_Comp, F));
1064 -- Ada 2005 (AI-287): In case of default initialized component, call
1065 -- the initialization subprogram associated with the component type.
1066 -- If the component type is an access type, add an explicit null
1067 -- assignment, because for the back-end there is an initialization
1068 -- present for the whole aggregate, and no default initialization
1071 -- In addition, if the component type is controlled, we must call
1072 -- its Initialize procedure explicitly, because there is no explicit
1073 -- object creation that will invoke it otherwise.
1076 if Present (Base_Init_Proc (Base_Type (Ctype)))
1077 or else Has_Task (Base_Type (Ctype))
1080 Build_Initialization_Call (Loc,
1081 Id_Ref => Indexed_Comp,
1083 With_Default_Init => True));
1085 elsif Is_Access_Type (Ctype) then
1087 Make_Assignment_Statement (Loc,
1088 Name => Indexed_Comp,
1089 Expression => Make_Null (Loc)));
1092 if Controlled_Type (Ctype) then
1095 Ref => New_Copy_Tree (Indexed_Comp),
1097 Flist_Ref => Find_Final_List (Current_Scope),
1098 With_Attach => Make_Integer_Literal (Loc, 1)));
1102 -- Now generate the assignment with no associated controlled
1103 -- actions since the target of the assignment may not have been
1104 -- initialized, it is not possible to Finalize it as expected by
1105 -- normal controlled assignment. The rest of the controlled
1106 -- actions are done manually with the proper finalization list
1107 -- coming from the context.
1110 Make_OK_Assignment_Statement (Loc,
1111 Name => Indexed_Comp,
1112 Expression => New_Copy_Tree (Expr));
1114 if Present (Comp_Type) and then Controlled_Type (Comp_Type) then
1115 Set_No_Ctrl_Actions (A);
1117 -- If this is an aggregate for an array of arrays, each
1118 -- sub-aggregate will be expanded as well, and even with
1119 -- No_Ctrl_Actions the assignments of inner components will
1120 -- require attachment in their assignments to temporaries.
1121 -- These temporaries must be finalized for each subaggregate,
1122 -- to prevent multiple attachments of the same temporary
1123 -- location to same finalization chain (and consequently
1124 -- circular lists). To ensure that finalization takes place
1125 -- for each subaggregate we wrap the assignment in a block.
1127 if Is_Array_Type (Comp_Type)
1128 and then Nkind (Expr) = N_Aggregate
1131 Make_Block_Statement (Loc,
1132 Handled_Statement_Sequence =>
1133 Make_Handled_Sequence_Of_Statements (Loc,
1134 Statements => New_List (A)));
1140 -- Adjust the tag if tagged (because of possible view
1141 -- conversions), unless compiling for the Java VM where
1142 -- tags are implicit.
1144 if Present (Comp_Type)
1145 and then Is_Tagged_Type (Comp_Type)
1146 and then VM_Target = No_VM
1149 Make_OK_Assignment_Statement (Loc,
1151 Make_Selected_Component (Loc,
1152 Prefix => New_Copy_Tree (Indexed_Comp),
1155 (First_Tag_Component (Comp_Type), Loc)),
1158 Unchecked_Convert_To (RTE (RE_Tag),
1160 (Node (First_Elmt (Access_Disp_Table (Comp_Type))),
1166 -- Adjust and attach the component to the proper final list, which
1167 -- can be the controller of the outer record object or the final
1168 -- list associated with the scope.
1170 -- If the component is itself an array of controlled types, whose
1171 -- value is given by a sub-aggregate, then the attach calls have
1172 -- been generated when individual subcomponent are assigned, and
1173 -- must not be done again to prevent malformed finalization chains
1174 -- (see comments above, concerning the creation of a block to hold
1175 -- inner finalization actions).
1177 if Present (Comp_Type)
1178 and then Controlled_Type (Comp_Type)
1179 and then not Is_Limited_Type (Comp_Type)
1181 (not Is_Array_Type (Comp_Type)
1182 or else not Is_Controlled (Component_Type (Comp_Type))
1183 or else Nkind (Expr) /= N_Aggregate)
1187 Ref => New_Copy_Tree (Indexed_Comp),
1190 With_Attach => Make_Integer_Literal (Loc, 1)));
1194 return Add_Loop_Actions (L);
1201 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id is
1205 -- Index_Base'(L) .. Index_Base'(H)
1207 L_Iteration_Scheme : Node_Id;
1208 -- L_J in Index_Base'(L) .. Index_Base'(H)
1211 -- The statements to execute in the loop
1213 S : constant List_Id := New_List;
1214 -- List of statements
1217 -- Copy of expression tree, used for checking purposes
1220 -- If loop bounds define an empty range return the null statement
1222 if Empty_Range (L, H) then
1223 Append_To (S, Make_Null_Statement (Loc));
1225 -- Ada 2005 (AI-287): Nothing else need to be done in case of
1226 -- default initialized component.
1232 -- The expression must be type-checked even though no component
1233 -- of the aggregate will have this value. This is done only for
1234 -- actual components of the array, not for subaggregates. Do
1235 -- the check on a copy, because the expression may be shared
1236 -- among several choices, some of which might be non-null.
1238 if Present (Etype (N))
1239 and then Is_Array_Type (Etype (N))
1240 and then No (Next_Index (Index))
1242 Expander_Mode_Save_And_Set (False);
1243 Tcopy := New_Copy_Tree (Expr);
1244 Set_Parent (Tcopy, N);
1245 Analyze_And_Resolve (Tcopy, Component_Type (Etype (N)));
1246 Expander_Mode_Restore;
1252 -- If loop bounds are the same then generate an assignment
1254 elsif Equal (L, H) then
1255 return Gen_Assign (New_Copy_Tree (L), Expr);
1257 -- If H - L <= 2 then generate a sequence of assignments when we are
1258 -- processing the bottom most aggregate and it contains scalar
1261 elsif No (Next_Index (Index))
1262 and then Scalar_Comp
1263 and then Local_Compile_Time_Known_Value (L)
1264 and then Local_Compile_Time_Known_Value (H)
1265 and then Local_Expr_Value (H) - Local_Expr_Value (L) <= 2
1268 Append_List_To (S, Gen_Assign (New_Copy_Tree (L), Expr));
1269 Append_List_To (S, Gen_Assign (Add (1, To => L), Expr));
1271 if Local_Expr_Value (H) - Local_Expr_Value (L) = 2 then
1272 Append_List_To (S, Gen_Assign (Add (2, To => L), Expr));
1278 -- Otherwise construct the loop, starting with the loop index L_J
1280 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
1282 -- Construct "L .. H"
1287 Low_Bound => Make_Qualified_Expression
1289 Subtype_Mark => Index_Base_Name,
1291 High_Bound => Make_Qualified_Expression
1293 Subtype_Mark => Index_Base_Name,
1296 -- Construct "for L_J in Index_Base range L .. H"
1298 L_Iteration_Scheme :=
1299 Make_Iteration_Scheme
1301 Loop_Parameter_Specification =>
1302 Make_Loop_Parameter_Specification
1304 Defining_Identifier => L_J,
1305 Discrete_Subtype_Definition => L_Range));
1307 -- Construct the statements to execute in the loop body
1309 L_Body := Gen_Assign (New_Reference_To (L_J, Loc), Expr);
1311 -- Construct the final loop
1313 Append_To (S, Make_Implicit_Loop_Statement
1315 Identifier => Empty,
1316 Iteration_Scheme => L_Iteration_Scheme,
1317 Statements => L_Body));
1319 -- A small optimization: if the aggregate is initialized with a box
1320 -- and the component type has no initialization procedure, remove the
1321 -- useless empty loop.
1323 if Nkind (First (S)) = N_Loop_Statement
1324 and then Is_Empty_List (Statements (First (S)))
1326 return New_List (Make_Null_Statement (Loc));
1336 -- The code built is
1338 -- W_J : Index_Base := L;
1339 -- while W_J < H loop
1340 -- W_J := Index_Base'Succ (W);
1344 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id is
1348 -- W_J : Base_Type := L;
1350 W_Iteration_Scheme : Node_Id;
1353 W_Index_Succ : Node_Id;
1354 -- Index_Base'Succ (J)
1356 W_Increment : Node_Id;
1357 -- W_J := Index_Base'Succ (W)
1359 W_Body : constant List_Id := New_List;
1360 -- The statements to execute in the loop
1362 S : constant List_Id := New_List;
1363 -- list of statement
1366 -- If loop bounds define an empty range or are equal return null
1368 if Empty_Range (L, H) or else Equal (L, H) then
1369 Append_To (S, Make_Null_Statement (Loc));
1373 -- Build the decl of W_J
1375 W_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
1377 Make_Object_Declaration
1379 Defining_Identifier => W_J,
1380 Object_Definition => Index_Base_Name,
1383 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1384 -- that in this particular case L is a fresh Expr generated by
1385 -- Add which we are the only ones to use.
1387 Append_To (S, W_Decl);
1389 -- Construct " while W_J < H"
1391 W_Iteration_Scheme :=
1392 Make_Iteration_Scheme
1394 Condition => Make_Op_Lt
1396 Left_Opnd => New_Reference_To (W_J, Loc),
1397 Right_Opnd => New_Copy_Tree (H)));
1399 -- Construct the statements to execute in the loop body
1402 Make_Attribute_Reference
1404 Prefix => Index_Base_Name,
1405 Attribute_Name => Name_Succ,
1406 Expressions => New_List (New_Reference_To (W_J, Loc)));
1409 Make_OK_Assignment_Statement
1411 Name => New_Reference_To (W_J, Loc),
1412 Expression => W_Index_Succ);
1414 Append_To (W_Body, W_Increment);
1415 Append_List_To (W_Body,
1416 Gen_Assign (New_Reference_To (W_J, Loc), Expr));
1418 -- Construct the final loop
1420 Append_To (S, Make_Implicit_Loop_Statement
1422 Identifier => Empty,
1423 Iteration_Scheme => W_Iteration_Scheme,
1424 Statements => W_Body));
1429 ---------------------
1430 -- Index_Base_Name --
1431 ---------------------
1433 function Index_Base_Name return Node_Id is
1435 return New_Reference_To (Index_Base, Sloc (N));
1436 end Index_Base_Name;
1438 ------------------------------------
1439 -- Local_Compile_Time_Known_Value --
1440 ------------------------------------
1442 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean is
1444 return Compile_Time_Known_Value (E)
1446 (Nkind (E) = N_Attribute_Reference
1447 and then Attribute_Name (E) = Name_Val
1448 and then Compile_Time_Known_Value (First (Expressions (E))));
1449 end Local_Compile_Time_Known_Value;
1451 ----------------------
1452 -- Local_Expr_Value --
1453 ----------------------
1455 function Local_Expr_Value (E : Node_Id) return Uint is
1457 if Compile_Time_Known_Value (E) then
1458 return Expr_Value (E);
1460 return Expr_Value (First (Expressions (E)));
1462 end Local_Expr_Value;
1464 -- Build_Array_Aggr_Code Variables
1471 Others_Expr : Node_Id := Empty;
1472 Others_Box_Present : Boolean := False;
1474 Aggr_L : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
1475 Aggr_H : constant Node_Id := High_Bound (Aggregate_Bounds (N));
1476 -- The aggregate bounds of this specific sub-aggregate. Note that if
1477 -- the code generated by Build_Array_Aggr_Code is executed then these
1478 -- bounds are OK. Otherwise a Constraint_Error would have been raised.
1480 Aggr_Low : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_L);
1481 Aggr_High : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_H);
1482 -- After Duplicate_Subexpr these are side-effect free
1487 Nb_Choices : Nat := 0;
1488 Table : Case_Table_Type (1 .. Number_Of_Choices (N));
1489 -- Used to sort all the different choice values
1492 -- Number of elements in the positional aggregate
1494 New_Code : constant List_Id := New_List;
1496 -- Start of processing for Build_Array_Aggr_Code
1499 -- First before we start, a special case. if we have a bit packed
1500 -- array represented as a modular type, then clear the value to
1501 -- zero first, to ensure that unused bits are properly cleared.
1506 and then Is_Bit_Packed_Array (Typ)
1507 and then Is_Modular_Integer_Type (Packed_Array_Type (Typ))
1509 Append_To (New_Code,
1510 Make_Assignment_Statement (Loc,
1511 Name => New_Copy_Tree (Into),
1513 Unchecked_Convert_To (Typ,
1514 Make_Integer_Literal (Loc, Uint_0))));
1517 -- STEP 1: Process component associations
1519 -- For those associations that may generate a loop, initialize
1520 -- Loop_Actions to collect inserted actions that may be crated.
1522 -- Skip this if no component associations
1524 if No (Expressions (N)) then
1526 -- STEP 1 (a): Sort the discrete choices
1528 Assoc := First (Component_Associations (N));
1529 while Present (Assoc) loop
1530 Choice := First (Choices (Assoc));
1531 while Present (Choice) loop
1532 if Nkind (Choice) = N_Others_Choice then
1533 Set_Loop_Actions (Assoc, New_List);
1535 if Box_Present (Assoc) then
1536 Others_Box_Present := True;
1538 Others_Expr := Expression (Assoc);
1543 Get_Index_Bounds (Choice, Low, High);
1546 Set_Loop_Actions (Assoc, New_List);
1549 Nb_Choices := Nb_Choices + 1;
1550 if Box_Present (Assoc) then
1551 Table (Nb_Choices) := (Choice_Lo => Low,
1553 Choice_Node => Empty);
1555 Table (Nb_Choices) := (Choice_Lo => Low,
1557 Choice_Node => Expression (Assoc));
1565 -- If there is more than one set of choices these must be static
1566 -- and we can therefore sort them. Remember that Nb_Choices does not
1567 -- account for an others choice.
1569 if Nb_Choices > 1 then
1570 Sort_Case_Table (Table);
1573 -- STEP 1 (b): take care of the whole set of discrete choices
1575 for J in 1 .. Nb_Choices loop
1576 Low := Table (J).Choice_Lo;
1577 High := Table (J).Choice_Hi;
1578 Expr := Table (J).Choice_Node;
1579 Append_List (Gen_Loop (Low, High, Expr), To => New_Code);
1582 -- STEP 1 (c): generate the remaining loops to cover others choice
1583 -- We don't need to generate loops over empty gaps, but if there is
1584 -- a single empty range we must analyze the expression for semantics
1586 if Present (Others_Expr) or else Others_Box_Present then
1588 First : Boolean := True;
1591 for J in 0 .. Nb_Choices loop
1595 Low := Add (1, To => Table (J).Choice_Hi);
1598 if J = Nb_Choices then
1601 High := Add (-1, To => Table (J + 1).Choice_Lo);
1604 -- If this is an expansion within an init proc, make
1605 -- sure that discriminant references are replaced by
1606 -- the corresponding discriminal.
1608 if Inside_Init_Proc then
1609 if Is_Entity_Name (Low)
1610 and then Ekind (Entity (Low)) = E_Discriminant
1612 Set_Entity (Low, Discriminal (Entity (Low)));
1615 if Is_Entity_Name (High)
1616 and then Ekind (Entity (High)) = E_Discriminant
1618 Set_Entity (High, Discriminal (Entity (High)));
1623 or else not Empty_Range (Low, High)
1627 (Gen_Loop (Low, High, Others_Expr), To => New_Code);
1633 -- STEP 2: Process positional components
1636 -- STEP 2 (a): Generate the assignments for each positional element
1637 -- Note that here we have to use Aggr_L rather than Aggr_Low because
1638 -- Aggr_L is analyzed and Add wants an analyzed expression.
1640 Expr := First (Expressions (N));
1642 while Present (Expr) loop
1643 Nb_Elements := Nb_Elements + 1;
1644 Append_List (Gen_Assign (Add (Nb_Elements, To => Aggr_L), Expr),
1649 -- STEP 2 (b): Generate final loop if an others choice is present
1650 -- Here Nb_Elements gives the offset of the last positional element.
1652 if Present (Component_Associations (N)) then
1653 Assoc := Last (Component_Associations (N));
1655 -- Ada 2005 (AI-287)
1657 if Box_Present (Assoc) then
1658 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1663 Expr := Expression (Assoc);
1665 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1674 end Build_Array_Aggr_Code;
1676 ----------------------------
1677 -- Build_Record_Aggr_Code --
1678 ----------------------------
1680 function Build_Record_Aggr_Code
1684 Flist : Node_Id := Empty;
1685 Obj : Entity_Id := Empty;
1686 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id
1688 Loc : constant Source_Ptr := Sloc (N);
1689 L : constant List_Id := New_List;
1690 N_Typ : constant Entity_Id := Etype (N);
1697 Comp_Type : Entity_Id;
1698 Selector : Entity_Id;
1699 Comp_Expr : Node_Id;
1702 Internal_Final_List : Node_Id := Empty;
1704 -- If this is an internal aggregate, the External_Final_List is an
1705 -- expression for the controller record of the enclosing type.
1707 -- If the current aggregate has several controlled components, this
1708 -- expression will appear in several calls to attach to the finali-
1709 -- zation list, and it must not be shared.
1711 External_Final_List : Node_Id;
1712 Ancestor_Is_Expression : Boolean := False;
1713 Ancestor_Is_Subtype_Mark : Boolean := False;
1715 Init_Typ : Entity_Id := Empty;
1718 Ctrl_Stuff_Done : Boolean := False;
1719 -- True if Gen_Ctrl_Actions_For_Aggr has already been called; calls
1720 -- after the first do nothing.
1722 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id;
1723 -- Returns the value that the given discriminant of an ancestor type
1724 -- should receive (in the absence of a conflict with the value provided
1725 -- by an ancestor part of an extension aggregate).
1727 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id);
1728 -- Check that each of the discriminant values defined by the ancestor
1729 -- part of an extension aggregate match the corresponding values
1730 -- provided by either an association of the aggregate or by the
1731 -- constraint imposed by a parent type (RM95-4.3.2(8)).
1733 function Compatible_Int_Bounds
1734 (Agg_Bounds : Node_Id;
1735 Typ_Bounds : Node_Id) return Boolean;
1736 -- Return true if Agg_Bounds are equal or within Typ_Bounds. It is
1737 -- assumed that both bounds are integer ranges.
1739 procedure Gen_Ctrl_Actions_For_Aggr;
1740 -- Deal with the various controlled type data structure initializations
1741 -- (but only if it hasn't been done already).
1743 function Get_Constraint_Association (T : Entity_Id) return Node_Id;
1744 -- Returns the first discriminant association in the constraint
1745 -- associated with T, if any, otherwise returns Empty.
1747 function Init_Controller
1752 Init_Pr : Boolean) return List_Id;
1753 -- Returns the list of statements necessary to initialize the internal
1754 -- controller of the (possible) ancestor typ into target and attach it
1755 -- to finalization list F. Init_Pr conditions the call to the init proc
1756 -- since it may already be done due to ancestor initialization.
1758 function Is_Int_Range_Bounds (Bounds : Node_Id) return Boolean;
1759 -- Check whether Bounds is a range node and its lower and higher bounds
1760 -- are integers literals.
1762 ---------------------------------
1763 -- Ancestor_Discriminant_Value --
1764 ---------------------------------
1766 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id is
1768 Assoc_Elmt : Elmt_Id;
1769 Aggr_Comp : Entity_Id;
1770 Corresp_Disc : Entity_Id;
1771 Current_Typ : Entity_Id := Base_Type (Typ);
1772 Parent_Typ : Entity_Id;
1773 Parent_Disc : Entity_Id;
1774 Save_Assoc : Node_Id := Empty;
1777 -- First check any discriminant associations to see if any of them
1778 -- provide a value for the discriminant.
1780 if Present (Discriminant_Specifications (Parent (Current_Typ))) then
1781 Assoc := First (Component_Associations (N));
1782 while Present (Assoc) loop
1783 Aggr_Comp := Entity (First (Choices (Assoc)));
1785 if Ekind (Aggr_Comp) = E_Discriminant then
1786 Save_Assoc := Expression (Assoc);
1788 Corresp_Disc := Corresponding_Discriminant (Aggr_Comp);
1789 while Present (Corresp_Disc) loop
1791 -- If found a corresponding discriminant then return the
1792 -- value given in the aggregate. (Note: this is not
1793 -- correct in the presence of side effects. ???)
1795 if Disc = Corresp_Disc then
1796 return Duplicate_Subexpr (Expression (Assoc));
1800 Corresponding_Discriminant (Corresp_Disc);
1808 -- No match found in aggregate, so chain up parent types to find
1809 -- a constraint that defines the value of the discriminant.
1811 Parent_Typ := Etype (Current_Typ);
1812 while Current_Typ /= Parent_Typ loop
1813 if Has_Discriminants (Parent_Typ) then
1814 Parent_Disc := First_Discriminant (Parent_Typ);
1816 -- We either get the association from the subtype indication
1817 -- of the type definition itself, or from the discriminant
1818 -- constraint associated with the type entity (which is
1819 -- preferable, but it's not always present ???)
1821 if Is_Empty_Elmt_List (
1822 Discriminant_Constraint (Current_Typ))
1824 Assoc := Get_Constraint_Association (Current_Typ);
1825 Assoc_Elmt := No_Elmt;
1828 First_Elmt (Discriminant_Constraint (Current_Typ));
1829 Assoc := Node (Assoc_Elmt);
1832 -- Traverse the discriminants of the parent type looking
1833 -- for one that corresponds.
1835 while Present (Parent_Disc) and then Present (Assoc) loop
1836 Corresp_Disc := Parent_Disc;
1837 while Present (Corresp_Disc)
1838 and then Disc /= Corresp_Disc
1841 Corresponding_Discriminant (Corresp_Disc);
1844 if Disc = Corresp_Disc then
1845 if Nkind (Assoc) = N_Discriminant_Association then
1846 Assoc := Expression (Assoc);
1849 -- If the located association directly denotes a
1850 -- discriminant, then use the value of a saved
1851 -- association of the aggregate. This is a kludge to
1852 -- handle certain cases involving multiple discriminants
1853 -- mapped to a single discriminant of a descendant. It's
1854 -- not clear how to locate the appropriate discriminant
1855 -- value for such cases. ???
1857 if Is_Entity_Name (Assoc)
1858 and then Ekind (Entity (Assoc)) = E_Discriminant
1860 Assoc := Save_Assoc;
1863 return Duplicate_Subexpr (Assoc);
1866 Next_Discriminant (Parent_Disc);
1868 if No (Assoc_Elmt) then
1871 Next_Elmt (Assoc_Elmt);
1872 if Present (Assoc_Elmt) then
1873 Assoc := Node (Assoc_Elmt);
1881 Current_Typ := Parent_Typ;
1882 Parent_Typ := Etype (Current_Typ);
1885 -- In some cases there's no ancestor value to locate (such as
1886 -- when an ancestor part given by an expression defines the
1887 -- discriminant value).
1890 end Ancestor_Discriminant_Value;
1892 ----------------------------------
1893 -- Check_Ancestor_Discriminants --
1894 ----------------------------------
1896 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id) is
1898 Disc_Value : Node_Id;
1902 Discr := First_Discriminant (Base_Type (Anc_Typ));
1903 while Present (Discr) loop
1904 Disc_Value := Ancestor_Discriminant_Value (Discr);
1906 if Present (Disc_Value) then
1907 Cond := Make_Op_Ne (Loc,
1909 Make_Selected_Component (Loc,
1910 Prefix => New_Copy_Tree (Target),
1911 Selector_Name => New_Occurrence_Of (Discr, Loc)),
1912 Right_Opnd => Disc_Value);
1915 Make_Raise_Constraint_Error (Loc,
1917 Reason => CE_Discriminant_Check_Failed));
1920 Next_Discriminant (Discr);
1922 end Check_Ancestor_Discriminants;
1924 ---------------------------
1925 -- Compatible_Int_Bounds --
1926 ---------------------------
1928 function Compatible_Int_Bounds
1929 (Agg_Bounds : Node_Id;
1930 Typ_Bounds : Node_Id) return Boolean
1932 Agg_Lo : constant Uint := Intval (Low_Bound (Agg_Bounds));
1933 Agg_Hi : constant Uint := Intval (High_Bound (Agg_Bounds));
1934 Typ_Lo : constant Uint := Intval (Low_Bound (Typ_Bounds));
1935 Typ_Hi : constant Uint := Intval (High_Bound (Typ_Bounds));
1937 return Typ_Lo <= Agg_Lo and then Agg_Hi <= Typ_Hi;
1938 end Compatible_Int_Bounds;
1940 --------------------------------
1941 -- Get_Constraint_Association --
1942 --------------------------------
1944 function Get_Constraint_Association (T : Entity_Id) return Node_Id is
1945 Typ_Def : constant Node_Id := Type_Definition (Parent (T));
1946 Indic : constant Node_Id := Subtype_Indication (Typ_Def);
1949 -- ??? Also need to cover case of a type mark denoting a subtype
1952 if Nkind (Indic) = N_Subtype_Indication
1953 and then Present (Constraint (Indic))
1955 return First (Constraints (Constraint (Indic)));
1959 end Get_Constraint_Association;
1961 ---------------------
1962 -- Init_Controller --
1963 ---------------------
1965 function Init_Controller
1970 Init_Pr : Boolean) return List_Id
1972 L : constant List_Id := New_List;
1975 Target_Type : Entity_Id;
1979 -- init-proc (target._controller);
1980 -- initialize (target._controller);
1981 -- Attach_to_Final_List (target._controller, F);
1984 Make_Selected_Component (Loc,
1985 Prefix => Convert_To (Typ, New_Copy_Tree (Target)),
1986 Selector_Name => Make_Identifier (Loc, Name_uController));
1987 Set_Assignment_OK (Ref);
1989 -- Ada 2005 (AI-287): Give support to aggregates of limited types.
1990 -- If the type is intrinsically limited the controller is limited as
1991 -- well. If it is tagged and limited then so is the controller.
1992 -- Otherwise an untagged type may have limited components without its
1993 -- full view being limited, so the controller is not limited.
1995 if Nkind (Target) = N_Identifier then
1996 Target_Type := Etype (Target);
1998 elsif Nkind (Target) = N_Selected_Component then
1999 Target_Type := Etype (Selector_Name (Target));
2001 elsif Nkind (Target) = N_Unchecked_Type_Conversion then
2002 Target_Type := Etype (Target);
2004 elsif Nkind (Target) = N_Unchecked_Expression
2005 and then Nkind (Expression (Target)) = N_Indexed_Component
2007 Target_Type := Etype (Prefix (Expression (Target)));
2010 Target_Type := Etype (Target);
2013 -- If the target has not been analyzed yet, as will happen with
2014 -- delayed expansion, use the given type (either the aggregate type
2015 -- or an ancestor) to determine limitedness.
2017 if No (Target_Type) then
2021 if (Is_Tagged_Type (Target_Type))
2022 and then Is_Limited_Type (Target_Type)
2024 RC := RE_Limited_Record_Controller;
2026 elsif Is_Inherently_Limited_Type (Target_Type) then
2027 RC := RE_Limited_Record_Controller;
2030 RC := RE_Record_Controller;
2035 Build_Initialization_Call (Loc,
2038 In_Init_Proc => Within_Init_Proc));
2042 Make_Procedure_Call_Statement (Loc,
2045 Find_Prim_Op (RTE (RC), Name_Initialize), Loc),
2046 Parameter_Associations =>
2047 New_List (New_Copy_Tree (Ref))));
2051 Obj_Ref => New_Copy_Tree (Ref),
2053 With_Attach => Attach));
2056 end Init_Controller;
2058 -------------------------
2059 -- Is_Int_Range_Bounds --
2060 -------------------------
2062 function Is_Int_Range_Bounds (Bounds : Node_Id) return Boolean is
2064 return Nkind (Bounds) = N_Range
2065 and then Nkind (Low_Bound (Bounds)) = N_Integer_Literal
2066 and then Nkind (High_Bound (Bounds)) = N_Integer_Literal;
2067 end Is_Int_Range_Bounds;
2069 -------------------------------
2070 -- Gen_Ctrl_Actions_For_Aggr --
2071 -------------------------------
2073 procedure Gen_Ctrl_Actions_For_Aggr is
2074 Alloc : Node_Id := Empty;
2077 -- Do the work only the first time this is called
2079 if Ctrl_Stuff_Done then
2083 Ctrl_Stuff_Done := True;
2086 and then Finalize_Storage_Only (Typ)
2088 (Is_Library_Level_Entity (Obj)
2089 or else Entity (Constant_Value (RTE (RE_Garbage_Collected))) =
2092 -- why not Is_True (Expr_Value (RTE (RE_Garbaage_Collected) ???
2094 Attach := Make_Integer_Literal (Loc, 0);
2096 elsif Nkind (Parent (N)) = N_Qualified_Expression
2097 and then Nkind (Parent (Parent (N))) = N_Allocator
2099 Alloc := Parent (Parent (N));
2100 Attach := Make_Integer_Literal (Loc, 2);
2103 Attach := Make_Integer_Literal (Loc, 1);
2106 -- Determine the external finalization list. It is either the
2107 -- finalization list of the outer-scope or the one coming from
2108 -- an outer aggregate. When the target is not a temporary, the
2109 -- proper scope is the scope of the target rather than the
2110 -- potentially transient current scope.
2112 if Controlled_Type (Typ) then
2114 -- The current aggregate belongs to an allocator which creates
2115 -- an object through an anonymous access type or acts as the root
2116 -- of a coextension chain.
2120 (Is_Coextension_Root (Alloc)
2121 or else Ekind (Etype (Alloc)) = E_Anonymous_Access_Type)
2123 if No (Associated_Final_Chain (Etype (Alloc))) then
2124 Build_Final_List (Alloc, Etype (Alloc));
2127 External_Final_List :=
2128 Make_Selected_Component (Loc,
2131 Associated_Final_Chain (Etype (Alloc)), Loc),
2133 Make_Identifier (Loc, Name_F));
2135 elsif Present (Flist) then
2136 External_Final_List := New_Copy_Tree (Flist);
2138 elsif Is_Entity_Name (Target)
2139 and then Present (Scope (Entity (Target)))
2141 External_Final_List :=
2142 Find_Final_List (Scope (Entity (Target)));
2145 External_Final_List := Find_Final_List (Current_Scope);
2148 External_Final_List := Empty;
2151 -- Initialize and attach the outer object in the is_controlled case
2153 if Is_Controlled (Typ) then
2154 if Ancestor_Is_Subtype_Mark then
2155 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2156 Set_Assignment_OK (Ref);
2158 Make_Procedure_Call_Statement (Loc,
2161 (Find_Prim_Op (Init_Typ, Name_Initialize), Loc),
2162 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
2165 if not Has_Controlled_Component (Typ) then
2166 Ref := New_Copy_Tree (Target);
2167 Set_Assignment_OK (Ref);
2169 -- This is an aggregate of a coextension. Do not produce a
2170 -- finalization call, but rather attach the reference of the
2171 -- aggregate to its coextension chain.
2174 and then Is_Dynamic_Coextension (Alloc)
2176 if No (Coextensions (Alloc)) then
2177 Set_Coextensions (Alloc, New_Elmt_List);
2180 Append_Elmt (Ref, Coextensions (Alloc));
2185 Flist_Ref => New_Copy_Tree (External_Final_List),
2186 With_Attach => Attach));
2191 -- In the Has_Controlled component case, all the intermediate
2192 -- controllers must be initialized.
2194 if Has_Controlled_Component (Typ)
2195 and not Is_Limited_Ancestor_Expansion
2198 Inner_Typ : Entity_Id;
2199 Outer_Typ : Entity_Id;
2203 -- Find outer type with a controller
2205 Outer_Typ := Base_Type (Typ);
2206 while Outer_Typ /= Init_Typ
2207 and then not Has_New_Controlled_Component (Outer_Typ)
2209 Outer_Typ := Etype (Outer_Typ);
2212 -- Attach it to the outer record controller to the external
2215 if Outer_Typ = Init_Typ then
2220 F => External_Final_List,
2225 Inner_Typ := Init_Typ;
2232 F => External_Final_List,
2236 Inner_Typ := Etype (Outer_Typ);
2238 not Is_Tagged_Type (Typ) or else Inner_Typ = Outer_Typ;
2241 -- The outer object has to be attached as well
2243 if Is_Controlled (Typ) then
2244 Ref := New_Copy_Tree (Target);
2245 Set_Assignment_OK (Ref);
2249 Flist_Ref => New_Copy_Tree (External_Final_List),
2250 With_Attach => New_Copy_Tree (Attach)));
2253 -- Initialize the internal controllers for tagged types with
2254 -- more than one controller.
2256 while not At_Root and then Inner_Typ /= Init_Typ loop
2257 if Has_New_Controlled_Component (Inner_Typ) then
2259 Make_Selected_Component (Loc,
2261 Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2263 Make_Identifier (Loc, Name_uController));
2265 Make_Selected_Component (Loc,
2267 Selector_Name => Make_Identifier (Loc, Name_F));
2274 Attach => Make_Integer_Literal (Loc, 1),
2276 Outer_Typ := Inner_Typ;
2281 At_Root := Inner_Typ = Etype (Inner_Typ);
2282 Inner_Typ := Etype (Inner_Typ);
2285 -- If not done yet attach the controller of the ancestor part
2287 if Outer_Typ /= Init_Typ
2288 and then Inner_Typ = Init_Typ
2289 and then Has_Controlled_Component (Init_Typ)
2292 Make_Selected_Component (Loc,
2293 Prefix => Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2295 Make_Identifier (Loc, Name_uController));
2297 Make_Selected_Component (Loc,
2299 Selector_Name => Make_Identifier (Loc, Name_F));
2301 Attach := Make_Integer_Literal (Loc, 1);
2310 -- Note: Init_Pr is False because the ancestor part has
2311 -- already been initialized either way (by default, if
2312 -- given by a type name, otherwise from the expression).
2317 end Gen_Ctrl_Actions_For_Aggr;
2319 function Replace_Type (Expr : Node_Id) return Traverse_Result;
2320 -- If the aggregate contains a self-reference, traverse each expression
2321 -- to replace a possible self-reference with a reference to the proper
2322 -- component of the target of the assignment.
2328 function Replace_Type (Expr : Node_Id) return Traverse_Result is
2330 -- Note regarding the Root_Type test below: Aggregate components for
2331 -- self-referential types include attribute references to the current
2332 -- instance, of the form: Typ'access, etc.. These references are
2333 -- rewritten as references to the target of the aggregate: the
2334 -- left-hand side of an assignment, the entity in a declaration,
2335 -- or a temporary. Without this test, we would improperly extended
2336 -- this rewriting to attribute references whose prefix was not the
2337 -- type of the aggregate.
2339 if Nkind (Expr) = N_Attribute_Reference
2340 and then Is_Entity_Name (Prefix (Expr))
2341 and then Is_Type (Entity (Prefix (Expr)))
2342 and then Root_Type (Etype (N)) = Root_Type (Entity (Prefix (Expr)))
2344 if Is_Entity_Name (Lhs) then
2345 Rewrite (Prefix (Expr),
2346 New_Occurrence_Of (Entity (Lhs), Loc));
2348 elsif Nkind (Lhs) = N_Selected_Component then
2350 Make_Attribute_Reference (Loc,
2351 Attribute_Name => Name_Unrestricted_Access,
2352 Prefix => New_Copy_Tree (Prefix (Lhs))));
2353 Set_Analyzed (Parent (Expr), False);
2357 Make_Attribute_Reference (Loc,
2358 Attribute_Name => Name_Unrestricted_Access,
2359 Prefix => New_Copy_Tree (Lhs)));
2360 Set_Analyzed (Parent (Expr), False);
2367 procedure Replace_Self_Reference is
2368 new Traverse_Proc (Replace_Type);
2370 -- Start of processing for Build_Record_Aggr_Code
2373 if Has_Self_Reference (N) then
2374 Replace_Self_Reference (N);
2377 -- If the target of the aggregate is class-wide, we must convert it
2378 -- to the actual type of the aggregate, so that the proper components
2379 -- are visible. We know already that the types are compatible.
2381 if Present (Etype (Lhs))
2382 and then Is_Interface (Etype (Lhs))
2384 Target := Unchecked_Convert_To (Typ, Lhs);
2389 -- Deal with the ancestor part of extension aggregates or with the
2390 -- discriminants of the root type.
2392 if Nkind (N) = N_Extension_Aggregate then
2394 A : constant Node_Id := Ancestor_Part (N);
2398 -- If the ancestor part is a subtype mark "T", we generate
2400 -- init-proc (T(tmp)); if T is constrained and
2401 -- init-proc (S(tmp)); where S applies an appropriate
2402 -- constraint if T is unconstrained
2404 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
2405 Ancestor_Is_Subtype_Mark := True;
2407 if Is_Constrained (Entity (A)) then
2408 Init_Typ := Entity (A);
2410 -- For an ancestor part given by an unconstrained type mark,
2411 -- create a subtype constrained by appropriate corresponding
2412 -- discriminant values coming from either associations of the
2413 -- aggregate or a constraint on a parent type. The subtype will
2414 -- be used to generate the correct default value for the
2417 elsif Has_Discriminants (Entity (A)) then
2419 Anc_Typ : constant Entity_Id := Entity (A);
2420 Anc_Constr : constant List_Id := New_List;
2421 Discrim : Entity_Id;
2422 Disc_Value : Node_Id;
2423 New_Indic : Node_Id;
2424 Subt_Decl : Node_Id;
2427 Discrim := First_Discriminant (Anc_Typ);
2428 while Present (Discrim) loop
2429 Disc_Value := Ancestor_Discriminant_Value (Discrim);
2430 Append_To (Anc_Constr, Disc_Value);
2431 Next_Discriminant (Discrim);
2435 Make_Subtype_Indication (Loc,
2436 Subtype_Mark => New_Occurrence_Of (Anc_Typ, Loc),
2438 Make_Index_Or_Discriminant_Constraint (Loc,
2439 Constraints => Anc_Constr));
2441 Init_Typ := Create_Itype (Ekind (Anc_Typ), N);
2444 Make_Subtype_Declaration (Loc,
2445 Defining_Identifier => Init_Typ,
2446 Subtype_Indication => New_Indic);
2448 -- Itypes must be analyzed with checks off Declaration
2449 -- must have a parent for proper handling of subsidiary
2452 Set_Parent (Subt_Decl, N);
2453 Analyze (Subt_Decl, Suppress => All_Checks);
2457 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2458 Set_Assignment_OK (Ref);
2460 if Has_Default_Init_Comps (N)
2461 or else Has_Task (Base_Type (Init_Typ))
2464 Build_Initialization_Call (Loc,
2467 In_Init_Proc => Within_Init_Proc,
2468 With_Default_Init => True));
2471 Build_Initialization_Call (Loc,
2474 In_Init_Proc => Within_Init_Proc));
2477 if Is_Constrained (Entity (A))
2478 and then Has_Discriminants (Entity (A))
2480 Check_Ancestor_Discriminants (Entity (A));
2483 -- Ada 2005 (AI-287): If the ancestor part is an aggregate of
2484 -- limited type, a recursive call expands the ancestor. Note that
2485 -- in the limited case, the ancestor part must be either a
2486 -- function call (possibly qualified, or wrapped in an unchecked
2487 -- conversion) or aggregate (definitely qualified).
2489 elsif Is_Limited_Type (Etype (A))
2490 and then Nkind (Unqualify (A)) /= N_Function_Call -- aggregate?
2492 (Nkind (Unqualify (A)) /= N_Unchecked_Type_Conversion
2494 Nkind (Expression (Unqualify (A))) /= N_Function_Call)
2496 Ancestor_Is_Expression := True;
2498 -- Set up finalization data for enclosing record, because
2499 -- controlled subcomponents of the ancestor part will be
2502 Gen_Ctrl_Actions_For_Aggr;
2505 Build_Record_Aggr_Code (
2507 Typ => Etype (Unqualify (A)),
2511 Is_Limited_Ancestor_Expansion => True));
2513 -- If the ancestor part is an expression "E", we generate
2517 -- In Ada 2005, this includes the case of a (possibly qualified)
2518 -- limited function call. The assignment will turn into a
2519 -- build-in-place function call (for further details, see
2520 -- Make_Build_In_Place_Call_In_Assignment).
2523 Ancestor_Is_Expression := True;
2524 Init_Typ := Etype (A);
2526 -- If the ancestor part is an aggregate, force its full
2527 -- expansion, which was delayed.
2529 if Nkind (Unqualify (A)) = N_Aggregate
2530 or else Nkind (Unqualify (A)) = N_Extension_Aggregate
2532 Set_Analyzed (A, False);
2533 Set_Analyzed (Expression (A), False);
2536 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2537 Set_Assignment_OK (Ref);
2539 -- Make the assignment without usual controlled actions since
2540 -- we only want the post adjust but not the pre finalize here
2541 -- Add manual adjust when necessary.
2543 Assign := New_List (
2544 Make_OK_Assignment_Statement (Loc,
2547 Set_No_Ctrl_Actions (First (Assign));
2549 -- Assign the tag now to make sure that the dispatching call in
2550 -- the subsequent deep_adjust works properly (unless VM_Target,
2551 -- where tags are implicit).
2553 if VM_Target = No_VM then
2555 Make_OK_Assignment_Statement (Loc,
2557 Make_Selected_Component (Loc,
2558 Prefix => New_Copy_Tree (Target),
2561 (First_Tag_Component (Base_Type (Typ)), Loc)),
2564 Unchecked_Convert_To (RTE (RE_Tag),
2567 (Access_Disp_Table (Base_Type (Typ)))),
2570 Set_Assignment_OK (Name (Instr));
2571 Append_To (Assign, Instr);
2573 -- Ada 2005 (AI-251): If tagged type has progenitors we must
2574 -- also initialize tags of the secondary dispatch tables.
2576 if Present (Abstract_Interfaces (Base_Type (Typ)))
2579 (Abstract_Interfaces (Base_Type (Typ)))
2582 (Typ => Base_Type (Typ),
2584 Stmts_List => Assign);
2588 -- Call Adjust manually
2590 if Controlled_Type (Etype (A))
2591 and then not Is_Limited_Type (Etype (A))
2593 Append_List_To (Assign,
2595 Ref => New_Copy_Tree (Ref),
2597 Flist_Ref => New_Reference_To (
2598 RTE (RE_Global_Final_List), Loc),
2599 With_Attach => Make_Integer_Literal (Loc, 0)));
2603 Make_Unsuppress_Block (Loc, Name_Discriminant_Check, Assign));
2605 if Has_Discriminants (Init_Typ) then
2606 Check_Ancestor_Discriminants (Init_Typ);
2611 -- Normal case (not an extension aggregate)
2614 -- Generate the discriminant expressions, component by component.
2615 -- If the base type is an unchecked union, the discriminants are
2616 -- unknown to the back-end and absent from a value of the type, so
2617 -- assignments for them are not emitted.
2619 if Has_Discriminants (Typ)
2620 and then not Is_Unchecked_Union (Base_Type (Typ))
2622 -- If the type is derived, and constrains discriminants of the
2623 -- parent type, these discriminants are not components of the
2624 -- aggregate, and must be initialized explicitly. They are not
2625 -- visible components of the object, but can become visible with
2626 -- a view conversion to the ancestor.
2630 Parent_Type : Entity_Id;
2632 Discr_Val : Elmt_Id;
2635 Btype := Base_Type (Typ);
2636 while Is_Derived_Type (Btype)
2637 and then Present (Stored_Constraint (Btype))
2639 Parent_Type := Etype (Btype);
2641 Disc := First_Discriminant (Parent_Type);
2643 First_Elmt (Stored_Constraint (Base_Type (Typ)));
2644 while Present (Discr_Val) loop
2646 -- Only those discriminants of the parent that are not
2647 -- renamed by discriminants of the derived type need to
2648 -- be added explicitly.
2650 if not Is_Entity_Name (Node (Discr_Val))
2652 Ekind (Entity (Node (Discr_Val))) /= E_Discriminant
2655 Make_Selected_Component (Loc,
2656 Prefix => New_Copy_Tree (Target),
2657 Selector_Name => New_Occurrence_Of (Disc, Loc));
2660 Make_OK_Assignment_Statement (Loc,
2662 Expression => New_Copy_Tree (Node (Discr_Val)));
2664 Set_No_Ctrl_Actions (Instr);
2665 Append_To (L, Instr);
2668 Next_Discriminant (Disc);
2669 Next_Elmt (Discr_Val);
2672 Btype := Base_Type (Parent_Type);
2676 -- Generate discriminant init values for the visible discriminants
2679 Discriminant : Entity_Id;
2680 Discriminant_Value : Node_Id;
2683 Discriminant := First_Stored_Discriminant (Typ);
2684 while Present (Discriminant) loop
2686 Make_Selected_Component (Loc,
2687 Prefix => New_Copy_Tree (Target),
2688 Selector_Name => New_Occurrence_Of (Discriminant, Loc));
2690 Discriminant_Value :=
2691 Get_Discriminant_Value (
2694 Discriminant_Constraint (N_Typ));
2697 Make_OK_Assignment_Statement (Loc,
2699 Expression => New_Copy_Tree (Discriminant_Value));
2701 Set_No_Ctrl_Actions (Instr);
2702 Append_To (L, Instr);
2704 Next_Stored_Discriminant (Discriminant);
2710 -- Generate the assignments, component by component
2712 -- tmp.comp1 := Expr1_From_Aggr;
2713 -- tmp.comp2 := Expr2_From_Aggr;
2716 Comp := First (Component_Associations (N));
2717 while Present (Comp) loop
2718 Selector := Entity (First (Choices (Comp)));
2720 -- Ada 2005 (AI-287): For each default-initialized component generate
2721 -- a call to the corresponding IP subprogram if available.
2723 if Box_Present (Comp)
2724 and then Has_Non_Null_Base_Init_Proc (Etype (Selector))
2726 if Ekind (Selector) /= E_Discriminant then
2727 Gen_Ctrl_Actions_For_Aggr;
2730 -- Ada 2005 (AI-287): If the component type has tasks then
2731 -- generate the activation chain and master entities (except
2732 -- in case of an allocator because in that case these entities
2733 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
2736 Ctype : constant Entity_Id := Etype (Selector);
2737 Inside_Allocator : Boolean := False;
2738 P : Node_Id := Parent (N);
2741 if Is_Task_Type (Ctype) or else Has_Task (Ctype) then
2742 while Present (P) loop
2743 if Nkind (P) = N_Allocator then
2744 Inside_Allocator := True;
2751 if not Inside_Init_Proc and not Inside_Allocator then
2752 Build_Activation_Chain_Entity (N);
2758 Build_Initialization_Call (Loc,
2759 Id_Ref => Make_Selected_Component (Loc,
2760 Prefix => New_Copy_Tree (Target),
2761 Selector_Name => New_Occurrence_Of (Selector,
2763 Typ => Etype (Selector),
2765 With_Default_Init => True));
2770 -- Prepare for component assignment
2772 if Ekind (Selector) /= E_Discriminant
2773 or else Nkind (N) = N_Extension_Aggregate
2775 -- All the discriminants have now been assigned
2777 -- This is now a good moment to initialize and attach all the
2778 -- controllers. Their position may depend on the discriminants.
2780 if Ekind (Selector) /= E_Discriminant then
2781 Gen_Ctrl_Actions_For_Aggr;
2784 Comp_Type := Etype (Selector);
2786 Make_Selected_Component (Loc,
2787 Prefix => New_Copy_Tree (Target),
2788 Selector_Name => New_Occurrence_Of (Selector, Loc));
2790 if Nkind (Expression (Comp)) = N_Qualified_Expression then
2791 Expr_Q := Expression (Expression (Comp));
2793 Expr_Q := Expression (Comp);
2796 -- The controller is the one of the parent type defining the
2797 -- component (in case of inherited components).
2799 if Controlled_Type (Comp_Type) then
2800 Internal_Final_List :=
2801 Make_Selected_Component (Loc,
2802 Prefix => Convert_To (
2803 Scope (Original_Record_Component (Selector)),
2804 New_Copy_Tree (Target)),
2806 Make_Identifier (Loc, Name_uController));
2808 Internal_Final_List :=
2809 Make_Selected_Component (Loc,
2810 Prefix => Internal_Final_List,
2811 Selector_Name => Make_Identifier (Loc, Name_F));
2813 -- The internal final list can be part of a constant object
2815 Set_Assignment_OK (Internal_Final_List);
2818 Internal_Final_List := Empty;
2821 -- Now either create the assignment or generate the code for the
2822 -- inner aggregate top-down.
2824 if Is_Delayed_Aggregate (Expr_Q) then
2826 -- We have the following case of aggregate nesting inside
2827 -- an object declaration:
2829 -- type Arr_Typ is array (Integer range <>) of ...;
2831 -- type Rec_Typ (...) is record
2832 -- Obj_Arr_Typ : Arr_Typ (A .. B);
2835 -- Obj_Rec_Typ : Rec_Typ := (...,
2836 -- Obj_Arr_Typ => (X => (...), Y => (...)));
2838 -- The length of the ranges of the aggregate and Obj_Add_Typ
2839 -- are equal (B - A = Y - X), but they do not coincide (X /=
2840 -- A and B /= Y). This case requires array sliding which is
2841 -- performed in the following manner:
2843 -- subtype Arr_Sub is Arr_Typ (X .. Y);
2845 -- Temp (X) := (...);
2847 -- Temp (Y) := (...);
2848 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
2850 if Ekind (Comp_Type) = E_Array_Subtype
2851 and then Is_Int_Range_Bounds (Aggregate_Bounds (Expr_Q))
2852 and then Is_Int_Range_Bounds (First_Index (Comp_Type))
2854 Compatible_Int_Bounds
2855 (Agg_Bounds => Aggregate_Bounds (Expr_Q),
2856 Typ_Bounds => First_Index (Comp_Type))
2858 -- Create the array subtype with bounds equal to those of
2859 -- the corresponding aggregate.
2862 SubE : constant Entity_Id :=
2863 Make_Defining_Identifier (Loc,
2864 New_Internal_Name ('T'));
2866 SubD : constant Node_Id :=
2867 Make_Subtype_Declaration (Loc,
2868 Defining_Identifier =>
2870 Subtype_Indication =>
2871 Make_Subtype_Indication (Loc,
2872 Subtype_Mark => New_Reference_To (
2873 Etype (Comp_Type), Loc),
2875 Make_Index_Or_Discriminant_Constraint (
2876 Loc, Constraints => New_List (
2877 New_Copy_Tree (Aggregate_Bounds (
2880 -- Create a temporary array of the above subtype which
2881 -- will be used to capture the aggregate assignments.
2883 TmpE : constant Entity_Id :=
2884 Make_Defining_Identifier (Loc,
2885 New_Internal_Name ('A'));
2887 TmpD : constant Node_Id :=
2888 Make_Object_Declaration (Loc,
2889 Defining_Identifier =>
2891 Object_Definition =>
2892 New_Reference_To (SubE, Loc));
2895 Set_No_Initialization (TmpD);
2896 Append_To (L, SubD);
2897 Append_To (L, TmpD);
2899 -- Expand aggregate into assignments to the temp array
2902 Late_Expansion (Expr_Q, Comp_Type,
2903 New_Reference_To (TmpE, Loc), Internal_Final_List));
2908 Make_Assignment_Statement (Loc,
2909 Name => New_Copy_Tree (Comp_Expr),
2910 Expression => New_Reference_To (TmpE, Loc)));
2912 -- Do not pass the original aggregate to Gigi as is,
2913 -- since it will potentially clobber the front or the end
2914 -- of the array. Setting the expression to empty is safe
2915 -- since all aggregates are expanded into assignments.
2917 if Present (Obj) then
2918 Set_Expression (Parent (Obj), Empty);
2922 -- Normal case (sliding not required)
2926 Late_Expansion (Expr_Q, Comp_Type, Comp_Expr,
2927 Internal_Final_List));
2930 -- Expr_Q is not delayed aggregate
2934 Make_OK_Assignment_Statement (Loc,
2936 Expression => Expression (Comp));
2938 Set_No_Ctrl_Actions (Instr);
2939 Append_To (L, Instr);
2941 -- Adjust the tag if tagged (because of possible view
2942 -- conversions), unless compiling for a VM where tags are
2945 -- tmp.comp._tag := comp_typ'tag;
2947 if Is_Tagged_Type (Comp_Type) and then VM_Target = No_VM then
2949 Make_OK_Assignment_Statement (Loc,
2951 Make_Selected_Component (Loc,
2952 Prefix => New_Copy_Tree (Comp_Expr),
2955 (First_Tag_Component (Comp_Type), Loc)),
2958 Unchecked_Convert_To (RTE (RE_Tag),
2960 (Node (First_Elmt (Access_Disp_Table (Comp_Type))),
2963 Append_To (L, Instr);
2966 -- Adjust and Attach the component to the proper controller
2968 -- Adjust (tmp.comp);
2969 -- Attach_To_Final_List (tmp.comp,
2970 -- comp_typ (tmp)._record_controller.f)
2972 if Controlled_Type (Comp_Type)
2973 and then not Is_Limited_Type (Comp_Type)
2977 Ref => New_Copy_Tree (Comp_Expr),
2979 Flist_Ref => Internal_Final_List,
2980 With_Attach => Make_Integer_Literal (Loc, 1)));
2986 elsif Ekind (Selector) = E_Discriminant
2987 and then Nkind (N) /= N_Extension_Aggregate
2988 and then Nkind (Parent (N)) = N_Component_Association
2989 and then Is_Constrained (Typ)
2991 -- We must check that the discriminant value imposed by the
2992 -- context is the same as the value given in the subaggregate,
2993 -- because after the expansion into assignments there is no
2994 -- record on which to perform a regular discriminant check.
3001 D_Val := First_Elmt (Discriminant_Constraint (Typ));
3002 Disc := First_Discriminant (Typ);
3003 while Chars (Disc) /= Chars (Selector) loop
3004 Next_Discriminant (Disc);
3008 pragma Assert (Present (D_Val));
3010 -- This check cannot performed for components that are
3011 -- constrained by a current instance, because this is not a
3012 -- value that can be compared with the actual constraint.
3014 if Nkind (Node (D_Val)) /= N_Attribute_Reference
3015 or else not Is_Entity_Name (Prefix (Node (D_Val)))
3016 or else not Is_Type (Entity (Prefix (Node (D_Val))))
3019 Make_Raise_Constraint_Error (Loc,
3022 Left_Opnd => New_Copy_Tree (Node (D_Val)),
3023 Right_Opnd => Expression (Comp)),
3024 Reason => CE_Discriminant_Check_Failed));
3027 -- Find self-reference in previous discriminant assignment,
3028 -- and replace with proper expression.
3035 while Present (Ass) loop
3036 if Nkind (Ass) = N_Assignment_Statement
3037 and then Nkind (Name (Ass)) = N_Selected_Component
3038 and then Chars (Selector_Name (Name (Ass))) =
3042 (Ass, New_Copy_Tree (Expression (Comp)));
3057 -- If the type is tagged, the tag needs to be initialized (unless
3058 -- compiling for the Java VM where tags are implicit). It is done
3059 -- late in the initialization process because in some cases, we call
3060 -- the init proc of an ancestor which will not leave out the right tag
3062 if Ancestor_Is_Expression then
3065 elsif Is_Tagged_Type (Typ) and then VM_Target = No_VM then
3067 Make_OK_Assignment_Statement (Loc,
3069 Make_Selected_Component (Loc,
3070 Prefix => New_Copy_Tree (Target),
3073 (First_Tag_Component (Base_Type (Typ)), Loc)),
3076 Unchecked_Convert_To (RTE (RE_Tag),
3078 (Node (First_Elmt (Access_Disp_Table (Base_Type (Typ)))),
3081 Append_To (L, Instr);
3083 -- Ada 2005 (AI-251): If the tagged type has been derived from
3084 -- abstract interfaces we must also initialize the tags of the
3085 -- secondary dispatch tables.
3087 if Present (Abstract_Interfaces (Base_Type (Typ)))
3089 Is_Empty_Elmt_List (Abstract_Interfaces (Base_Type (Typ)))
3092 (Typ => Base_Type (Typ),
3098 -- If the controllers have not been initialized yet (by lack of non-
3099 -- discriminant components), let's do it now.
3101 Gen_Ctrl_Actions_For_Aggr;
3104 end Build_Record_Aggr_Code;
3106 -------------------------------
3107 -- Convert_Aggr_In_Allocator --
3108 -------------------------------
3110 procedure Convert_Aggr_In_Allocator
3115 Loc : constant Source_Ptr := Sloc (Aggr);
3116 Typ : constant Entity_Id := Etype (Aggr);
3117 Temp : constant Entity_Id := Defining_Identifier (Decl);
3119 Occ : constant Node_Id :=
3120 Unchecked_Convert_To (Typ,
3121 Make_Explicit_Dereference (Loc,
3122 New_Reference_To (Temp, Loc)));
3124 Access_Type : constant Entity_Id := Etype (Temp);
3128 -- If the allocator is for an access discriminant, there is no
3129 -- finalization list for the anonymous access type, and the eventual
3130 -- finalization of the object is handled through the coextension
3131 -- mechanism. If the enclosing object is not dynamically allocated,
3132 -- the access discriminant is itself placed on the stack. Otherwise,
3133 -- some other finalization list is used (see exp_ch4.adb).
3135 -- Decl has been inserted in the code ahead of the allocator, using
3136 -- Insert_Actions. We use Insert_Actions below as well, to ensure that
3137 -- subsequent insertions are done in the proper order. Using (for
3138 -- example) Insert_Actions_After to place the expanded aggregate
3139 -- immediately after Decl may lead to out-of-order references if the
3140 -- allocator has generated a finalization list, as when the designated
3141 -- object is controlled and there is an open transient scope.
3143 if Ekind (Access_Type) = E_Anonymous_Access_Type
3144 and then Nkind (Associated_Node_For_Itype (Access_Type)) =
3145 N_Discriminant_Specification
3149 Flist := Find_Final_List (Access_Type);
3152 if Is_Array_Type (Typ) then
3153 Convert_Array_Aggr_In_Allocator (Decl, Aggr, Occ);
3155 elsif Has_Default_Init_Comps (Aggr) then
3157 L : constant List_Id := New_List;
3158 Init_Stmts : List_Id;
3165 Associated_Final_Chain (Base_Type (Access_Type)));
3167 -- ??? Dubious actual for Obj: expect 'the original object being
3170 if Has_Task (Typ) then
3171 Build_Task_Allocate_Block_With_Init_Stmts (L, Aggr, Init_Stmts);
3172 Insert_Actions (Alloc, L);
3174 Insert_Actions (Alloc, Init_Stmts);
3179 Insert_Actions (Alloc,
3181 (Aggr, Typ, Occ, Flist,
3182 Associated_Final_Chain (Base_Type (Access_Type))));
3184 -- ??? Dubious actual for Obj: expect 'the original object being
3188 end Convert_Aggr_In_Allocator;
3190 --------------------------------
3191 -- Convert_Aggr_In_Assignment --
3192 --------------------------------
3194 procedure Convert_Aggr_In_Assignment (N : Node_Id) is
3195 Aggr : Node_Id := Expression (N);
3196 Typ : constant Entity_Id := Etype (Aggr);
3197 Occ : constant Node_Id := New_Copy_Tree (Name (N));
3200 if Nkind (Aggr) = N_Qualified_Expression then
3201 Aggr := Expression (Aggr);
3204 Insert_Actions_After (N,
3207 Find_Final_List (Typ, New_Copy_Tree (Occ))));
3208 end Convert_Aggr_In_Assignment;
3210 ---------------------------------
3211 -- Convert_Aggr_In_Object_Decl --
3212 ---------------------------------
3214 procedure Convert_Aggr_In_Object_Decl (N : Node_Id) is
3215 Obj : constant Entity_Id := Defining_Identifier (N);
3216 Aggr : Node_Id := Expression (N);
3217 Loc : constant Source_Ptr := Sloc (Aggr);
3218 Typ : constant Entity_Id := Etype (Aggr);
3219 Occ : constant Node_Id := New_Occurrence_Of (Obj, Loc);
3221 function Discriminants_Ok return Boolean;
3222 -- If the object type is constrained, the discriminants in the
3223 -- aggregate must be checked against the discriminants of the subtype.
3224 -- This cannot be done using Apply_Discriminant_Checks because after
3225 -- expansion there is no aggregate left to check.
3227 ----------------------
3228 -- Discriminants_Ok --
3229 ----------------------
3231 function Discriminants_Ok return Boolean is
3232 Cond : Node_Id := Empty;
3241 D := First_Discriminant (Typ);
3242 Disc1 := First_Elmt (Discriminant_Constraint (Typ));
3243 Disc2 := First_Elmt (Discriminant_Constraint (Etype (Obj)));
3244 while Present (Disc1) and then Present (Disc2) loop
3245 Val1 := Node (Disc1);
3246 Val2 := Node (Disc2);
3248 if not Is_OK_Static_Expression (Val1)
3249 or else not Is_OK_Static_Expression (Val2)
3251 Check := Make_Op_Ne (Loc,
3252 Left_Opnd => Duplicate_Subexpr (Val1),
3253 Right_Opnd => Duplicate_Subexpr (Val2));
3259 Cond := Make_Or_Else (Loc,
3261 Right_Opnd => Check);
3264 elsif Expr_Value (Val1) /= Expr_Value (Val2) then
3265 Apply_Compile_Time_Constraint_Error (Aggr,
3266 Msg => "incorrect value for discriminant&?",
3267 Reason => CE_Discriminant_Check_Failed,
3272 Next_Discriminant (D);
3277 -- If any discriminant constraint is non-static, emit a check
3279 if Present (Cond) then
3281 Make_Raise_Constraint_Error (Loc,
3283 Reason => CE_Discriminant_Check_Failed));
3287 end Discriminants_Ok;
3289 -- Start of processing for Convert_Aggr_In_Object_Decl
3292 Set_Assignment_OK (Occ);
3294 if Nkind (Aggr) = N_Qualified_Expression then
3295 Aggr := Expression (Aggr);
3298 if Has_Discriminants (Typ)
3299 and then Typ /= Etype (Obj)
3300 and then Is_Constrained (Etype (Obj))
3301 and then not Discriminants_Ok
3306 -- If the context is an extended return statement, it has its own
3307 -- finalization machinery (i.e. works like a transient scope) and
3308 -- we do not want to create an additional one, because objects on
3309 -- the finalization list of the return must be moved to the caller's
3310 -- finalization list to complete the return.
3312 -- However, if the aggregate is limited, it is built in place, and the
3313 -- controlled components are not assigned to intermediate temporaries
3314 -- so there is no need for a transient scope in this case either.
3316 if Requires_Transient_Scope (Typ)
3317 and then Ekind (Current_Scope) /= E_Return_Statement
3318 and then not Is_Limited_Type (Typ)
3320 Establish_Transient_Scope (Aggr, Sec_Stack =>
3321 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
3324 Insert_Actions_After (N, Late_Expansion (Aggr, Typ, Occ, Obj => Obj));
3325 Set_No_Initialization (N);
3326 Initialize_Discriminants (N, Typ);
3327 end Convert_Aggr_In_Object_Decl;
3329 -------------------------------------
3330 -- Convert_Array_Aggr_In_Allocator --
3331 -------------------------------------
3333 procedure Convert_Array_Aggr_In_Allocator
3338 Aggr_Code : List_Id;
3339 Typ : constant Entity_Id := Etype (Aggr);
3340 Ctyp : constant Entity_Id := Component_Type (Typ);
3343 -- The target is an explicit dereference of the allocated object.
3344 -- Generate component assignments to it, as for an aggregate that
3345 -- appears on the right-hand side of an assignment statement.
3348 Build_Array_Aggr_Code (Aggr,
3350 Index => First_Index (Typ),
3352 Scalar_Comp => Is_Scalar_Type (Ctyp));
3354 Insert_Actions_After (Decl, Aggr_Code);
3355 end Convert_Array_Aggr_In_Allocator;
3357 ----------------------------
3358 -- Convert_To_Assignments --
3359 ----------------------------
3361 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id) is
3362 Loc : constant Source_Ptr := Sloc (N);
3366 Target_Expr : Node_Id;
3367 Parent_Kind : Node_Kind;
3368 Unc_Decl : Boolean := False;
3369 Parent_Node : Node_Id;
3372 pragma Assert (not Is_Static_Dispatch_Table_Aggregate (N));
3373 pragma Assert (Is_Record_Type (Typ));
3375 Parent_Node := Parent (N);
3376 Parent_Kind := Nkind (Parent_Node);
3378 if Parent_Kind = N_Qualified_Expression then
3380 -- Check if we are in a unconstrained declaration because in this
3381 -- case the current delayed expansion mechanism doesn't work when
3382 -- the declared object size depend on the initializing expr.
3385 Parent_Node := Parent (Parent_Node);
3386 Parent_Kind := Nkind (Parent_Node);
3388 if Parent_Kind = N_Object_Declaration then
3390 not Is_Entity_Name (Object_Definition (Parent_Node))
3391 or else Has_Discriminants
3392 (Entity (Object_Definition (Parent_Node)))
3393 or else Is_Class_Wide_Type
3394 (Entity (Object_Definition (Parent_Node)));
3399 -- Just set the Delay flag in the cases where the transformation will be
3400 -- done top down from above.
3404 -- Internal aggregate (transformed when expanding the parent)
3406 or else Parent_Kind = N_Aggregate
3407 or else Parent_Kind = N_Extension_Aggregate
3408 or else Parent_Kind = N_Component_Association
3410 -- Allocator (see Convert_Aggr_In_Allocator)
3412 or else Parent_Kind = N_Allocator
3414 -- Object declaration (see Convert_Aggr_In_Object_Decl)
3416 or else (Parent_Kind = N_Object_Declaration and then not Unc_Decl)
3418 -- Safe assignment (see Convert_Aggr_Assignments). So far only the
3419 -- assignments in init procs are taken into account.
3421 or else (Parent_Kind = N_Assignment_Statement
3422 and then Inside_Init_Proc)
3424 -- (Ada 2005) An inherently limited type in a return statement,
3425 -- which will be handled in a build-in-place fashion, and may be
3426 -- rewritten as an extended return and have its own finalization
3427 -- machinery. In the case of a simple return, the aggregate needs
3428 -- to be delayed until the scope for the return statement has been
3429 -- created, so that any finalization chain will be associated with
3430 -- that scope. For extended returns, we delay expansion to avoid the
3431 -- creation of an unwanted transient scope that could result in
3432 -- premature finalization of the return object (which is built in
3433 -- in place within the caller's scope).
3436 (Is_Inherently_Limited_Type (Typ)
3438 (Nkind (Parent (Parent_Node)) = N_Extended_Return_Statement
3439 or else Nkind (Parent_Node) = N_Simple_Return_Statement))
3441 Set_Expansion_Delayed (N);
3445 if Requires_Transient_Scope (Typ) then
3446 Establish_Transient_Scope
3448 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
3451 -- If the aggregate is non-limited, create a temporary. If it is
3452 -- limited and the context is an assignment, this is a subaggregate
3453 -- for an enclosing aggregate being expanded. It must be built in place,
3454 -- so use the target of the current assignment.
3456 if Is_Limited_Type (Typ)
3457 and then Nkind (Parent (N)) = N_Assignment_Statement
3459 Target_Expr := New_Copy_Tree (Name (Parent (N)));
3461 (Parent (N), Build_Record_Aggr_Code (N, Typ, Target_Expr));
3462 Rewrite (Parent (N), Make_Null_Statement (Loc));
3465 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
3468 Make_Object_Declaration (Loc,
3469 Defining_Identifier => Temp,
3470 Object_Definition => New_Occurrence_Of (Typ, Loc));
3472 Set_No_Initialization (Instr);
3473 Insert_Action (N, Instr);
3474 Initialize_Discriminants (Instr, Typ);
3475 Target_Expr := New_Occurrence_Of (Temp, Loc);
3476 Insert_Actions (N, Build_Record_Aggr_Code (N, Typ, Target_Expr));
3477 Rewrite (N, New_Occurrence_Of (Temp, Loc));
3478 Analyze_And_Resolve (N, Typ);
3480 end Convert_To_Assignments;
3482 ---------------------------
3483 -- Convert_To_Positional --
3484 ---------------------------
3486 procedure Convert_To_Positional
3488 Max_Others_Replicate : Nat := 5;
3489 Handle_Bit_Packed : Boolean := False)
3491 Typ : constant Entity_Id := Etype (N);
3493 Static_Components : Boolean := True;
3495 procedure Check_Static_Components;
3496 -- Check whether all components of the aggregate are compile-time known
3497 -- values, and can be passed as is to the back-end without further
3503 Ixb : Node_Id) return Boolean;
3504 -- Convert the aggregate into a purely positional form if possible. On
3505 -- entry the bounds of all dimensions are known to be static, and the
3506 -- total number of components is safe enough to expand.
3508 function Is_Flat (N : Node_Id; Dims : Int) return Boolean;
3509 -- Return True iff the array N is flat (which is not rivial in the case
3510 -- of multidimensionsl aggregates).
3512 -----------------------------
3513 -- Check_Static_Components --
3514 -----------------------------
3516 procedure Check_Static_Components is
3520 Static_Components := True;
3522 if Nkind (N) = N_String_Literal then
3525 elsif Present (Expressions (N)) then
3526 Expr := First (Expressions (N));
3527 while Present (Expr) loop
3528 if Nkind (Expr) /= N_Aggregate
3529 or else not Compile_Time_Known_Aggregate (Expr)
3530 or else Expansion_Delayed (Expr)
3532 Static_Components := False;
3540 if Nkind (N) = N_Aggregate
3541 and then Present (Component_Associations (N))
3543 Expr := First (Component_Associations (N));
3544 while Present (Expr) loop
3545 if Nkind (Expression (Expr)) = N_Integer_Literal then
3548 elsif Nkind (Expression (Expr)) /= N_Aggregate
3550 not Compile_Time_Known_Aggregate (Expression (Expr))
3551 or else Expansion_Delayed (Expression (Expr))
3553 Static_Components := False;
3560 end Check_Static_Components;
3569 Ixb : Node_Id) return Boolean
3571 Loc : constant Source_Ptr := Sloc (N);
3572 Blo : constant Node_Id := Type_Low_Bound (Etype (Ixb));
3573 Lo : constant Node_Id := Type_Low_Bound (Etype (Ix));
3574 Hi : constant Node_Id := Type_High_Bound (Etype (Ix));
3579 if Nkind (Original_Node (N)) = N_String_Literal then
3583 if not Compile_Time_Known_Value (Lo)
3584 or else not Compile_Time_Known_Value (Hi)
3589 Lov := Expr_Value (Lo);
3590 Hiv := Expr_Value (Hi);
3593 or else not Compile_Time_Known_Value (Blo)
3598 -- Determine if set of alternatives is suitable for conversion and
3599 -- build an array containing the values in sequence.
3602 Vals : array (UI_To_Int (Lov) .. UI_To_Int (Hiv))
3603 of Node_Id := (others => Empty);
3604 -- The values in the aggregate sorted appropriately
3607 -- Same data as Vals in list form
3610 -- Used to validate Max_Others_Replicate limit
3613 Num : Int := UI_To_Int (Lov);
3618 if Present (Expressions (N)) then
3619 Elmt := First (Expressions (N));
3620 while Present (Elmt) loop
3621 if Nkind (Elmt) = N_Aggregate
3622 and then Present (Next_Index (Ix))
3624 not Flatten (Elmt, Next_Index (Ix), Next_Index (Ixb))
3629 Vals (Num) := Relocate_Node (Elmt);
3636 if No (Component_Associations (N)) then
3640 Elmt := First (Component_Associations (N));
3642 if Nkind (Expression (Elmt)) = N_Aggregate then
3643 if Present (Next_Index (Ix))
3646 (Expression (Elmt), Next_Index (Ix), Next_Index (Ixb))
3652 Component_Loop : while Present (Elmt) loop
3653 Choice := First (Choices (Elmt));
3654 Choice_Loop : while Present (Choice) loop
3656 -- If we have an others choice, fill in the missing elements
3657 -- subject to the limit established by Max_Others_Replicate.
3659 if Nkind (Choice) = N_Others_Choice then
3662 for J in Vals'Range loop
3663 if No (Vals (J)) then
3664 Vals (J) := New_Copy_Tree (Expression (Elmt));
3665 Rep_Count := Rep_Count + 1;
3667 -- Check for maximum others replication. Note that
3668 -- we skip this test if either of the restrictions
3669 -- No_Elaboration_Code or No_Implicit_Loops is
3670 -- active, or if this is a preelaborable unit.
3673 P : constant Entity_Id :=
3674 Cunit_Entity (Current_Sem_Unit);
3677 if Restriction_Active (No_Elaboration_Code)
3678 or else Restriction_Active (No_Implicit_Loops)
3679 or else Is_Preelaborated (P)
3680 or else (Ekind (P) = E_Package_Body
3682 Is_Preelaborated (Spec_Entity (P)))
3686 elsif Rep_Count > Max_Others_Replicate then
3693 exit Component_Loop;
3695 -- Case of a subtype mark
3697 elsif Nkind (Choice) = N_Identifier
3698 and then Is_Type (Entity (Choice))
3700 Lo := Type_Low_Bound (Etype (Choice));
3701 Hi := Type_High_Bound (Etype (Choice));
3703 -- Case of subtype indication
3705 elsif Nkind (Choice) = N_Subtype_Indication then
3706 Lo := Low_Bound (Range_Expression (Constraint (Choice)));
3707 Hi := High_Bound (Range_Expression (Constraint (Choice)));
3711 elsif Nkind (Choice) = N_Range then
3712 Lo := Low_Bound (Choice);
3713 Hi := High_Bound (Choice);
3715 -- Normal subexpression case
3717 else pragma Assert (Nkind (Choice) in N_Subexpr);
3718 if not Compile_Time_Known_Value (Choice) then
3722 Vals (UI_To_Int (Expr_Value (Choice))) :=
3723 New_Copy_Tree (Expression (Elmt));
3728 -- Range cases merge with Lo,Hi said
3730 if not Compile_Time_Known_Value (Lo)
3732 not Compile_Time_Known_Value (Hi)
3736 for J in UI_To_Int (Expr_Value (Lo)) ..
3737 UI_To_Int (Expr_Value (Hi))
3739 Vals (J) := New_Copy_Tree (Expression (Elmt));
3745 end loop Choice_Loop;
3748 end loop Component_Loop;
3750 -- If we get here the conversion is possible
3753 for J in Vals'Range loop
3754 Append (Vals (J), Vlist);
3757 Rewrite (N, Make_Aggregate (Loc, Expressions => Vlist));
3758 Set_Aggregate_Bounds (N, Aggregate_Bounds (Original_Node (N)));
3767 function Is_Flat (N : Node_Id; Dims : Int) return Boolean is
3774 elsif Nkind (N) = N_Aggregate then
3775 if Present (Component_Associations (N)) then
3779 Elmt := First (Expressions (N));
3780 while Present (Elmt) loop
3781 if not Is_Flat (Elmt, Dims - 1) then
3795 -- Start of processing for Convert_To_Positional
3798 -- Ada 2005 (AI-287): Do not convert in case of default initialized
3799 -- components because in this case will need to call the corresponding
3802 if Has_Default_Init_Comps (N) then
3806 if Is_Flat (N, Number_Dimensions (Typ)) then
3810 if Is_Bit_Packed_Array (Typ)
3811 and then not Handle_Bit_Packed
3816 -- Do not convert to positional if controlled components are involved
3817 -- since these require special processing
3819 if Has_Controlled_Component (Typ) then
3823 Check_Static_Components;
3825 -- If the size is known, or all the components are static, try to
3826 -- build a fully positional aggregate.
3828 -- The size of the type may not be known for an aggregate with
3829 -- discriminated array components, but if the components are static
3830 -- it is still possible to verify statically that the length is
3831 -- compatible with the upper bound of the type, and therefore it is
3832 -- worth flattening such aggregates as well.
3834 -- For now the back-end expands these aggregates into individual
3835 -- assignments to the target anyway, but it is conceivable that
3836 -- it will eventually be able to treat such aggregates statically???
3838 if Aggr_Size_OK (Typ)
3839 and then Flatten (N, First_Index (Typ), First_Index (Base_Type (Typ)))
3841 if Static_Components then
3842 Set_Compile_Time_Known_Aggregate (N);
3843 Set_Expansion_Delayed (N, False);
3846 Analyze_And_Resolve (N, Typ);
3848 end Convert_To_Positional;
3850 ----------------------------
3851 -- Expand_Array_Aggregate --
3852 ----------------------------
3854 -- Array aggregate expansion proceeds as follows:
3856 -- 1. If requested we generate code to perform all the array aggregate
3857 -- bound checks, specifically
3859 -- (a) Check that the index range defined by aggregate bounds is
3860 -- compatible with corresponding index subtype.
3862 -- (b) If an others choice is present check that no aggregate
3863 -- index is outside the bounds of the index constraint.
3865 -- (c) For multidimensional arrays make sure that all subaggregates
3866 -- corresponding to the same dimension have the same bounds.
3868 -- 2. Check for packed array aggregate which can be converted to a
3869 -- constant so that the aggregate disappeares completely.
3871 -- 3. Check case of nested aggregate. Generally nested aggregates are
3872 -- handled during the processing of the parent aggregate.
3874 -- 4. Check if the aggregate can be statically processed. If this is the
3875 -- case pass it as is to Gigi. Note that a necessary condition for
3876 -- static processing is that the aggregate be fully positional.
3878 -- 5. If in place aggregate expansion is possible (i.e. no need to create
3879 -- a temporary) then mark the aggregate as such and return. Otherwise
3880 -- create a new temporary and generate the appropriate initialization
3883 procedure Expand_Array_Aggregate (N : Node_Id) is
3884 Loc : constant Source_Ptr := Sloc (N);
3886 Typ : constant Entity_Id := Etype (N);
3887 Ctyp : constant Entity_Id := Component_Type (Typ);
3888 -- Typ is the correct constrained array subtype of the aggregate
3889 -- Ctyp is the corresponding component type.
3891 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
3892 -- Number of aggregate index dimensions
3894 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id;
3895 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id;
3896 -- Low and High bounds of the constraint for each aggregate index
3898 Aggr_Index_Typ : array (1 .. Aggr_Dimension) of Entity_Id;
3899 -- The type of each index
3901 Maybe_In_Place_OK : Boolean;
3902 -- If the type is neither controlled nor packed and the aggregate
3903 -- is the expression in an assignment, assignment in place may be
3904 -- possible, provided other conditions are met on the LHS.
3906 Others_Present : array (1 .. Aggr_Dimension) of Boolean :=
3908 -- If Others_Present (J) is True, then there is an others choice
3909 -- in one of the sub-aggregates of N at dimension J.
3911 procedure Build_Constrained_Type (Positional : Boolean);
3912 -- If the subtype is not static or unconstrained, build a constrained
3913 -- type using the computable sizes of the aggregate and its sub-
3916 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id);
3917 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
3920 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos);
3921 -- Checks that in a multi-dimensional array aggregate all subaggregates
3922 -- corresponding to the same dimension have the same bounds.
3923 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
3924 -- corresponding to the sub-aggregate.
3926 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos);
3927 -- Computes the values of array Others_Present. Sub_Aggr is the
3928 -- array sub-aggregate we start the computation from. Dim is the
3929 -- dimension corresponding to the sub-aggregate.
3931 function Has_Address_Clause (D : Node_Id) return Boolean;
3932 -- If the aggregate is the expression in an object declaration, it
3933 -- cannot be expanded in place. This function does a lookahead in the
3934 -- current declarative part to find an address clause for the object
3937 function In_Place_Assign_OK return Boolean;
3938 -- Simple predicate to determine whether an aggregate assignment can
3939 -- be done in place, because none of the new values can depend on the
3940 -- components of the target of the assignment.
3942 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos);
3943 -- Checks that if an others choice is present in any sub-aggregate no
3944 -- aggregate index is outside the bounds of the index constraint.
3945 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
3946 -- corresponding to the sub-aggregate.
3948 ----------------------------
3949 -- Build_Constrained_Type --
3950 ----------------------------
3952 procedure Build_Constrained_Type (Positional : Boolean) is
3953 Loc : constant Source_Ptr := Sloc (N);
3954 Agg_Type : Entity_Id;
3957 Typ : constant Entity_Id := Etype (N);
3958 Indices : constant List_Id := New_List;
3964 Make_Defining_Identifier (
3965 Loc, New_Internal_Name ('A'));
3967 -- If the aggregate is purely positional, all its subaggregates
3968 -- have the same size. We collect the dimensions from the first
3969 -- subaggregate at each level.
3974 for D in 1 .. Number_Dimensions (Typ) loop
3975 Sub_Agg := First (Expressions (Sub_Agg));
3979 while Present (Comp) loop
3986 Low_Bound => Make_Integer_Literal (Loc, 1),
3988 Make_Integer_Literal (Loc, Num)),
3993 -- We know the aggregate type is unconstrained and the aggregate
3994 -- is not processable by the back end, therefore not necessarily
3995 -- positional. Retrieve each dimension bounds (computed earlier).
3998 for D in 1 .. Number_Dimensions (Typ) loop
4001 Low_Bound => Aggr_Low (D),
4002 High_Bound => Aggr_High (D)),
4008 Make_Full_Type_Declaration (Loc,
4009 Defining_Identifier => Agg_Type,
4011 Make_Constrained_Array_Definition (Loc,
4012 Discrete_Subtype_Definitions => Indices,
4013 Component_Definition =>
4014 Make_Component_Definition (Loc,
4015 Aliased_Present => False,
4016 Subtype_Indication =>
4017 New_Occurrence_Of (Component_Type (Typ), Loc))));
4019 Insert_Action (N, Decl);
4021 Set_Etype (N, Agg_Type);
4022 Set_Is_Itype (Agg_Type);
4023 Freeze_Itype (Agg_Type, N);
4024 end Build_Constrained_Type;
4030 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id) is
4037 Cond : Node_Id := Empty;
4040 Get_Index_Bounds (Aggr_Bounds, Aggr_Lo, Aggr_Hi);
4041 Get_Index_Bounds (Index_Bounds, Ind_Lo, Ind_Hi);
4043 -- Generate the following test:
4045 -- [constraint_error when
4046 -- Aggr_Lo <= Aggr_Hi and then
4047 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
4049 -- As an optimization try to see if some tests are trivially vacuos
4050 -- because we are comparing an expression against itself.
4052 if Aggr_Lo = Ind_Lo and then Aggr_Hi = Ind_Hi then
4055 elsif Aggr_Hi = Ind_Hi then
4058 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4059 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo));
4061 elsif Aggr_Lo = Ind_Lo then
4064 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
4065 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Hi));
4072 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4073 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo)),
4077 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
4078 Right_Opnd => Duplicate_Subexpr (Ind_Hi)));
4081 if Present (Cond) then
4086 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4087 Right_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi)),
4089 Right_Opnd => Cond);
4091 Set_Analyzed (Left_Opnd (Left_Opnd (Cond)), False);
4092 Set_Analyzed (Right_Opnd (Left_Opnd (Cond)), False);
4094 Make_Raise_Constraint_Error (Loc,
4096 Reason => CE_Length_Check_Failed));
4100 ----------------------------
4101 -- Check_Same_Aggr_Bounds --
4102 ----------------------------
4104 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos) is
4105 Sub_Lo : constant Node_Id := Low_Bound (Aggregate_Bounds (Sub_Aggr));
4106 Sub_Hi : constant Node_Id := High_Bound (Aggregate_Bounds (Sub_Aggr));
4107 -- The bounds of this specific sub-aggregate
4109 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
4110 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
4111 -- The bounds of the aggregate for this dimension
4113 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
4114 -- The index type for this dimension.xxx
4116 Cond : Node_Id := Empty;
4121 -- If index checks are on generate the test
4123 -- [constraint_error when
4124 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
4126 -- As an optimization try to see if some tests are trivially vacuos
4127 -- because we are comparing an expression against itself. Also for
4128 -- the first dimension the test is trivially vacuous because there
4129 -- is just one aggregate for dimension 1.
4131 if Index_Checks_Suppressed (Ind_Typ) then
4135 or else (Aggr_Lo = Sub_Lo and then Aggr_Hi = Sub_Hi)
4139 elsif Aggr_Hi = Sub_Hi then
4142 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4143 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo));
4145 elsif Aggr_Lo = Sub_Lo then
4148 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
4149 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Hi));
4156 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4157 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo)),
4161 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
4162 Right_Opnd => Duplicate_Subexpr (Sub_Hi)));
4165 if Present (Cond) then
4167 Make_Raise_Constraint_Error (Loc,
4169 Reason => CE_Length_Check_Failed));
4172 -- Now look inside the sub-aggregate to see if there is more work
4174 if Dim < Aggr_Dimension then
4176 -- Process positional components
4178 if Present (Expressions (Sub_Aggr)) then
4179 Expr := First (Expressions (Sub_Aggr));
4180 while Present (Expr) loop
4181 Check_Same_Aggr_Bounds (Expr, Dim + 1);
4186 -- Process component associations
4188 if Present (Component_Associations (Sub_Aggr)) then
4189 Assoc := First (Component_Associations (Sub_Aggr));
4190 while Present (Assoc) loop
4191 Expr := Expression (Assoc);
4192 Check_Same_Aggr_Bounds (Expr, Dim + 1);
4197 end Check_Same_Aggr_Bounds;
4199 ----------------------------
4200 -- Compute_Others_Present --
4201 ----------------------------
4203 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos) is
4208 if Present (Component_Associations (Sub_Aggr)) then
4209 Assoc := Last (Component_Associations (Sub_Aggr));
4211 if Nkind (First (Choices (Assoc))) = N_Others_Choice then
4212 Others_Present (Dim) := True;
4216 -- Now look inside the sub-aggregate to see if there is more work
4218 if Dim < Aggr_Dimension then
4220 -- Process positional components
4222 if Present (Expressions (Sub_Aggr)) then
4223 Expr := First (Expressions (Sub_Aggr));
4224 while Present (Expr) loop
4225 Compute_Others_Present (Expr, Dim + 1);
4230 -- Process component associations
4232 if Present (Component_Associations (Sub_Aggr)) then
4233 Assoc := First (Component_Associations (Sub_Aggr));
4234 while Present (Assoc) loop
4235 Expr := Expression (Assoc);
4236 Compute_Others_Present (Expr, Dim + 1);
4241 end Compute_Others_Present;
4243 ------------------------
4244 -- Has_Address_Clause --
4245 ------------------------
4247 function Has_Address_Clause (D : Node_Id) return Boolean is
4248 Id : constant Entity_Id := Defining_Identifier (D);
4253 while Present (Decl) loop
4254 if Nkind (Decl) = N_At_Clause
4255 and then Chars (Identifier (Decl)) = Chars (Id)
4259 elsif Nkind (Decl) = N_Attribute_Definition_Clause
4260 and then Chars (Decl) = Name_Address
4261 and then Chars (Name (Decl)) = Chars (Id)
4270 end Has_Address_Clause;
4272 ------------------------
4273 -- In_Place_Assign_OK --
4274 ------------------------
4276 function In_Place_Assign_OK return Boolean is
4284 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean;
4285 -- Aggregates that consist of a single Others choice are safe
4286 -- if the single expression is.
4288 function Safe_Aggregate (Aggr : Node_Id) return Boolean;
4289 -- Check recursively that each component of a (sub)aggregate does
4290 -- not depend on the variable being assigned to.
4292 function Safe_Component (Expr : Node_Id) return Boolean;
4293 -- Verify that an expression cannot depend on the variable being
4294 -- assigned to. Room for improvement here (but less than before).
4296 -------------------------
4297 -- Is_Others_Aggregate --
4298 -------------------------
4300 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean is
4302 return No (Expressions (Aggr))
4304 (First (Choices (First (Component_Associations (Aggr)))))
4306 end Is_Others_Aggregate;
4308 --------------------
4309 -- Safe_Aggregate --
4310 --------------------
4312 function Safe_Aggregate (Aggr : Node_Id) return Boolean is
4316 if Present (Expressions (Aggr)) then
4317 Expr := First (Expressions (Aggr));
4318 while Present (Expr) loop
4319 if Nkind (Expr) = N_Aggregate then
4320 if not Safe_Aggregate (Expr) then
4324 elsif not Safe_Component (Expr) then
4332 if Present (Component_Associations (Aggr)) then
4333 Expr := First (Component_Associations (Aggr));
4334 while Present (Expr) loop
4335 if Nkind (Expression (Expr)) = N_Aggregate then
4336 if not Safe_Aggregate (Expression (Expr)) then
4340 elsif not Safe_Component (Expression (Expr)) then
4351 --------------------
4352 -- Safe_Component --
4353 --------------------
4355 function Safe_Component (Expr : Node_Id) return Boolean is
4356 Comp : Node_Id := Expr;
4358 function Check_Component (Comp : Node_Id) return Boolean;
4359 -- Do the recursive traversal, after copy
4361 ---------------------
4362 -- Check_Component --
4363 ---------------------
4365 function Check_Component (Comp : Node_Id) return Boolean is
4367 if Is_Overloaded (Comp) then
4371 return Compile_Time_Known_Value (Comp)
4373 or else (Is_Entity_Name (Comp)
4374 and then Present (Entity (Comp))
4375 and then No (Renamed_Object (Entity (Comp))))
4377 or else (Nkind (Comp) = N_Attribute_Reference
4378 and then Check_Component (Prefix (Comp)))
4380 or else (Nkind (Comp) in N_Binary_Op
4381 and then Check_Component (Left_Opnd (Comp))
4382 and then Check_Component (Right_Opnd (Comp)))
4384 or else (Nkind (Comp) in N_Unary_Op
4385 and then Check_Component (Right_Opnd (Comp)))
4387 or else (Nkind (Comp) = N_Selected_Component
4388 and then Check_Component (Prefix (Comp)))
4390 or else (Nkind (Comp) = N_Unchecked_Type_Conversion
4391 and then Check_Component (Expression (Comp)));
4392 end Check_Component;
4394 -- Start of processing for Safe_Component
4397 -- If the component appears in an association that may
4398 -- correspond to more than one element, it is not analyzed
4399 -- before the expansion into assignments, to avoid side effects.
4400 -- We analyze, but do not resolve the copy, to obtain sufficient
4401 -- entity information for the checks that follow. If component is
4402 -- overloaded we assume an unsafe function call.
4404 if not Analyzed (Comp) then
4405 if Is_Overloaded (Expr) then
4408 elsif Nkind (Expr) = N_Aggregate
4409 and then not Is_Others_Aggregate (Expr)
4413 elsif Nkind (Expr) = N_Allocator then
4415 -- For now, too complex to analyze
4420 Comp := New_Copy_Tree (Expr);
4421 Set_Parent (Comp, Parent (Expr));
4425 if Nkind (Comp) = N_Aggregate then
4426 return Safe_Aggregate (Comp);
4428 return Check_Component (Comp);
4432 -- Start of processing for In_Place_Assign_OK
4435 if Present (Component_Associations (N)) then
4437 -- On assignment, sliding can take place, so we cannot do the
4438 -- assignment in place unless the bounds of the aggregate are
4439 -- statically equal to those of the target.
4441 -- If the aggregate is given by an others choice, the bounds
4442 -- are derived from the left-hand side, and the assignment is
4443 -- safe if the expression is.
4445 if Is_Others_Aggregate (N) then
4448 (Expression (First (Component_Associations (N))));
4451 Aggr_In := First_Index (Etype (N));
4452 if Nkind (Parent (N)) = N_Assignment_Statement then
4453 Obj_In := First_Index (Etype (Name (Parent (N))));
4456 -- Context is an allocator. Check bounds of aggregate
4457 -- against given type in qualified expression.
4459 pragma Assert (Nkind (Parent (Parent (N))) = N_Allocator);
4461 First_Index (Etype (Entity (Subtype_Mark (Parent (N)))));
4464 while Present (Aggr_In) loop
4465 Get_Index_Bounds (Aggr_In, Aggr_Lo, Aggr_Hi);
4466 Get_Index_Bounds (Obj_In, Obj_Lo, Obj_Hi);
4468 if not Compile_Time_Known_Value (Aggr_Lo)
4469 or else not Compile_Time_Known_Value (Aggr_Hi)
4470 or else not Compile_Time_Known_Value (Obj_Lo)
4471 or else not Compile_Time_Known_Value (Obj_Hi)
4472 or else Expr_Value (Aggr_Lo) /= Expr_Value (Obj_Lo)
4473 or else Expr_Value (Aggr_Hi) /= Expr_Value (Obj_Hi)
4478 Next_Index (Aggr_In);
4479 Next_Index (Obj_In);
4483 -- Now check the component values themselves
4485 return Safe_Aggregate (N);
4486 end In_Place_Assign_OK;
4492 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos) is
4493 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
4494 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
4495 -- The bounds of the aggregate for this dimension
4497 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
4498 -- The index type for this dimension
4500 Need_To_Check : Boolean := False;
4502 Choices_Lo : Node_Id := Empty;
4503 Choices_Hi : Node_Id := Empty;
4504 -- The lowest and highest discrete choices for a named sub-aggregate
4506 Nb_Choices : Int := -1;
4507 -- The number of discrete non-others choices in this sub-aggregate
4509 Nb_Elements : Uint := Uint_0;
4510 -- The number of elements in a positional aggregate
4512 Cond : Node_Id := Empty;
4519 -- Check if we have an others choice. If we do make sure that this
4520 -- sub-aggregate contains at least one element in addition to the
4523 if Range_Checks_Suppressed (Ind_Typ) then
4524 Need_To_Check := False;
4526 elsif Present (Expressions (Sub_Aggr))
4527 and then Present (Component_Associations (Sub_Aggr))
4529 Need_To_Check := True;
4531 elsif Present (Component_Associations (Sub_Aggr)) then
4532 Assoc := Last (Component_Associations (Sub_Aggr));
4534 if Nkind (First (Choices (Assoc))) /= N_Others_Choice then
4535 Need_To_Check := False;
4538 -- Count the number of discrete choices. Start with -1 because
4539 -- the others choice does not count.
4542 Assoc := First (Component_Associations (Sub_Aggr));
4543 while Present (Assoc) loop
4544 Choice := First (Choices (Assoc));
4545 while Present (Choice) loop
4546 Nb_Choices := Nb_Choices + 1;
4553 -- If there is only an others choice nothing to do
4555 Need_To_Check := (Nb_Choices > 0);
4559 Need_To_Check := False;
4562 -- If we are dealing with a positional sub-aggregate with an others
4563 -- choice then compute the number or positional elements.
4565 if Need_To_Check and then Present (Expressions (Sub_Aggr)) then
4566 Expr := First (Expressions (Sub_Aggr));
4567 Nb_Elements := Uint_0;
4568 while Present (Expr) loop
4569 Nb_Elements := Nb_Elements + 1;
4573 -- If the aggregate contains discrete choices and an others choice
4574 -- compute the smallest and largest discrete choice values.
4576 elsif Need_To_Check then
4577 Compute_Choices_Lo_And_Choices_Hi : declare
4579 Table : Case_Table_Type (1 .. Nb_Choices);
4580 -- Used to sort all the different choice values
4587 Assoc := First (Component_Associations (Sub_Aggr));
4588 while Present (Assoc) loop
4589 Choice := First (Choices (Assoc));
4590 while Present (Choice) loop
4591 if Nkind (Choice) = N_Others_Choice then
4595 Get_Index_Bounds (Choice, Low, High);
4596 Table (J).Choice_Lo := Low;
4597 Table (J).Choice_Hi := High;
4606 -- Sort the discrete choices
4608 Sort_Case_Table (Table);
4610 Choices_Lo := Table (1).Choice_Lo;
4611 Choices_Hi := Table (Nb_Choices).Choice_Hi;
4612 end Compute_Choices_Lo_And_Choices_Hi;
4615 -- If no others choice in this sub-aggregate, or the aggregate
4616 -- comprises only an others choice, nothing to do.
4618 if not Need_To_Check then
4621 -- If we are dealing with an aggregate containing an others choice
4622 -- and positional components, we generate the following test:
4624 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
4625 -- Ind_Typ'Pos (Aggr_Hi)
4627 -- raise Constraint_Error;
4630 elsif Nb_Elements > Uint_0 then
4636 Make_Attribute_Reference (Loc,
4637 Prefix => New_Reference_To (Ind_Typ, Loc),
4638 Attribute_Name => Name_Pos,
4641 (Duplicate_Subexpr_Move_Checks (Aggr_Lo))),
4642 Right_Opnd => Make_Integer_Literal (Loc, Nb_Elements - 1)),
4645 Make_Attribute_Reference (Loc,
4646 Prefix => New_Reference_To (Ind_Typ, Loc),
4647 Attribute_Name => Name_Pos,
4648 Expressions => New_List (
4649 Duplicate_Subexpr_Move_Checks (Aggr_Hi))));
4651 -- If we are dealing with an aggregate containing an others choice
4652 -- and discrete choices we generate the following test:
4654 -- [constraint_error when
4655 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
4663 Duplicate_Subexpr_Move_Checks (Choices_Lo),
4665 Duplicate_Subexpr_Move_Checks (Aggr_Lo)),
4670 Duplicate_Subexpr (Choices_Hi),
4672 Duplicate_Subexpr (Aggr_Hi)));
4675 if Present (Cond) then
4677 Make_Raise_Constraint_Error (Loc,
4679 Reason => CE_Length_Check_Failed));
4682 -- Now look inside the sub-aggregate to see if there is more work
4684 if Dim < Aggr_Dimension then
4686 -- Process positional components
4688 if Present (Expressions (Sub_Aggr)) then
4689 Expr := First (Expressions (Sub_Aggr));
4690 while Present (Expr) loop
4691 Others_Check (Expr, Dim + 1);
4696 -- Process component associations
4698 if Present (Component_Associations (Sub_Aggr)) then
4699 Assoc := First (Component_Associations (Sub_Aggr));
4700 while Present (Assoc) loop
4701 Expr := Expression (Assoc);
4702 Others_Check (Expr, Dim + 1);
4709 -- Remaining Expand_Array_Aggregate variables
4712 -- Holds the temporary aggregate value
4715 -- Holds the declaration of Tmp
4717 Aggr_Code : List_Id;
4718 Parent_Node : Node_Id;
4719 Parent_Kind : Node_Kind;
4721 -- Start of processing for Expand_Array_Aggregate
4724 -- Do not touch the special aggregates of attributes used for Asm calls
4726 if Is_RTE (Ctyp, RE_Asm_Input_Operand)
4727 or else Is_RTE (Ctyp, RE_Asm_Output_Operand)
4732 -- If the semantic analyzer has determined that aggregate N will raise
4733 -- Constraint_Error at run-time, then the aggregate node has been
4734 -- replaced with an N_Raise_Constraint_Error node and we should
4737 pragma Assert (not Raises_Constraint_Error (N));
4741 -- Check that the index range defined by aggregate bounds is
4742 -- compatible with corresponding index subtype.
4744 Index_Compatibility_Check : declare
4745 Aggr_Index_Range : Node_Id := First_Index (Typ);
4746 -- The current aggregate index range
4748 Index_Constraint : Node_Id := First_Index (Etype (Typ));
4749 -- The corresponding index constraint against which we have to
4750 -- check the above aggregate index range.
4753 Compute_Others_Present (N, 1);
4755 for J in 1 .. Aggr_Dimension loop
4756 -- There is no need to emit a check if an others choice is
4757 -- present for this array aggregate dimension since in this
4758 -- case one of N's sub-aggregates has taken its bounds from the
4759 -- context and these bounds must have been checked already. In
4760 -- addition all sub-aggregates corresponding to the same
4761 -- dimension must all have the same bounds (checked in (c) below).
4763 if not Range_Checks_Suppressed (Etype (Index_Constraint))
4764 and then not Others_Present (J)
4766 -- We don't use Checks.Apply_Range_Check here because it emits
4767 -- a spurious check. Namely it checks that the range defined by
4768 -- the aggregate bounds is non empty. But we know this already
4771 Check_Bounds (Aggr_Index_Range, Index_Constraint);
4774 -- Save the low and high bounds of the aggregate index as well as
4775 -- the index type for later use in checks (b) and (c) below.
4777 Aggr_Low (J) := Low_Bound (Aggr_Index_Range);
4778 Aggr_High (J) := High_Bound (Aggr_Index_Range);
4780 Aggr_Index_Typ (J) := Etype (Index_Constraint);
4782 Next_Index (Aggr_Index_Range);
4783 Next_Index (Index_Constraint);
4785 end Index_Compatibility_Check;
4789 -- If an others choice is present check that no aggregate index is
4790 -- outside the bounds of the index constraint.
4792 Others_Check (N, 1);
4796 -- For multidimensional arrays make sure that all subaggregates
4797 -- corresponding to the same dimension have the same bounds.
4799 if Aggr_Dimension > 1 then
4800 Check_Same_Aggr_Bounds (N, 1);
4805 -- Here we test for is packed array aggregate that we can handle at
4806 -- compile time. If so, return with transformation done. Note that we do
4807 -- this even if the aggregate is nested, because once we have done this
4808 -- processing, there is no more nested aggregate!
4810 if Packed_Array_Aggregate_Handled (N) then
4814 -- At this point we try to convert to positional form
4816 if Ekind (Current_Scope) = E_Package
4817 and then Static_Elaboration_Desired (Current_Scope)
4819 Convert_To_Positional (N, Max_Others_Replicate => 100);
4822 Convert_To_Positional (N);
4825 -- if the result is no longer an aggregate (e.g. it may be a string
4826 -- literal, or a temporary which has the needed value), then we are
4827 -- done, since there is no longer a nested aggregate.
4829 if Nkind (N) /= N_Aggregate then
4832 -- We are also done if the result is an analyzed aggregate
4833 -- This case could use more comments ???
4836 and then N /= Original_Node (N)
4841 -- If all aggregate components are compile-time known and the aggregate
4842 -- has been flattened, nothing left to do. The same occurs if the
4843 -- aggregate is used to initialize the components of an statically
4844 -- allocated dispatch table.
4846 if Compile_Time_Known_Aggregate (N)
4847 or else Is_Static_Dispatch_Table_Aggregate (N)
4849 Set_Expansion_Delayed (N, False);
4853 -- Now see if back end processing is possible
4855 if Backend_Processing_Possible (N) then
4857 -- If the aggregate is static but the constraints are not, build
4858 -- a static subtype for the aggregate, so that Gigi can place it
4859 -- in static memory. Perform an unchecked_conversion to the non-
4860 -- static type imposed by the context.
4863 Itype : constant Entity_Id := Etype (N);
4865 Needs_Type : Boolean := False;
4868 Index := First_Index (Itype);
4869 while Present (Index) loop
4870 if not Is_Static_Subtype (Etype (Index)) then
4879 Build_Constrained_Type (Positional => True);
4880 Rewrite (N, Unchecked_Convert_To (Itype, N));
4890 -- Delay expansion for nested aggregates it will be taken care of
4891 -- when the parent aggregate is expanded
4893 Parent_Node := Parent (N);
4894 Parent_Kind := Nkind (Parent_Node);
4896 if Parent_Kind = N_Qualified_Expression then
4897 Parent_Node := Parent (Parent_Node);
4898 Parent_Kind := Nkind (Parent_Node);
4901 if Parent_Kind = N_Aggregate
4902 or else Parent_Kind = N_Extension_Aggregate
4903 or else Parent_Kind = N_Component_Association
4904 or else (Parent_Kind = N_Object_Declaration
4905 and then Controlled_Type (Typ))
4906 or else (Parent_Kind = N_Assignment_Statement
4907 and then Inside_Init_Proc)
4909 if Static_Array_Aggregate (N)
4910 or else Compile_Time_Known_Aggregate (N)
4912 Set_Expansion_Delayed (N, False);
4915 Set_Expansion_Delayed (N);
4922 -- Look if in place aggregate expansion is possible
4924 -- For object declarations we build the aggregate in place, unless
4925 -- the array is bit-packed or the component is controlled.
4927 -- For assignments we do the assignment in place if all the component
4928 -- associations have compile-time known values. For other cases we
4929 -- create a temporary. The analysis for safety of on-line assignment
4930 -- is delicate, i.e. we don't know how to do it fully yet ???
4932 -- For allocators we assign to the designated object in place if the
4933 -- aggregate meets the same conditions as other in-place assignments.
4934 -- In this case the aggregate may not come from source but was created
4935 -- for default initialization, e.g. with Initialize_Scalars.
4937 if Requires_Transient_Scope (Typ) then
4938 Establish_Transient_Scope
4939 (N, Sec_Stack => Has_Controlled_Component (Typ));
4942 if Has_Default_Init_Comps (N) then
4943 Maybe_In_Place_OK := False;
4945 elsif Is_Bit_Packed_Array (Typ)
4946 or else Has_Controlled_Component (Typ)
4948 Maybe_In_Place_OK := False;
4951 Maybe_In_Place_OK :=
4952 (Nkind (Parent (N)) = N_Assignment_Statement
4953 and then Comes_From_Source (N)
4954 and then In_Place_Assign_OK)
4957 (Nkind (Parent (Parent (N))) = N_Allocator
4958 and then In_Place_Assign_OK);
4961 if not Has_Default_Init_Comps (N)
4962 and then Comes_From_Source (Parent (N))
4963 and then Nkind (Parent (N)) = N_Object_Declaration
4965 Must_Slide (Etype (Defining_Identifier (Parent (N))), Typ)
4966 and then N = Expression (Parent (N))
4967 and then not Is_Bit_Packed_Array (Typ)
4968 and then not Has_Controlled_Component (Typ)
4969 and then not Has_Address_Clause (Parent (N))
4971 Tmp := Defining_Identifier (Parent (N));
4972 Set_No_Initialization (Parent (N));
4973 Set_Expression (Parent (N), Empty);
4975 -- Set the type of the entity, for use in the analysis of the
4976 -- subsequent indexed assignments. If the nominal type is not
4977 -- constrained, build a subtype from the known bounds of the
4978 -- aggregate. If the declaration has a subtype mark, use it,
4979 -- otherwise use the itype of the aggregate.
4981 if not Is_Constrained (Typ) then
4982 Build_Constrained_Type (Positional => False);
4983 elsif Is_Entity_Name (Object_Definition (Parent (N)))
4984 and then Is_Constrained (Entity (Object_Definition (Parent (N))))
4986 Set_Etype (Tmp, Entity (Object_Definition (Parent (N))));
4988 Set_Size_Known_At_Compile_Time (Typ, False);
4989 Set_Etype (Tmp, Typ);
4992 elsif Maybe_In_Place_OK
4993 and then Nkind (Parent (N)) = N_Qualified_Expression
4994 and then Nkind (Parent (Parent (N))) = N_Allocator
4996 Set_Expansion_Delayed (N);
4999 -- In the remaining cases the aggregate is the RHS of an assignment
5001 elsif Maybe_In_Place_OK
5002 and then Is_Entity_Name (Name (Parent (N)))
5004 Tmp := Entity (Name (Parent (N)));
5006 if Etype (Tmp) /= Etype (N) then
5007 Apply_Length_Check (N, Etype (Tmp));
5009 if Nkind (N) = N_Raise_Constraint_Error then
5011 -- Static error, nothing further to expand
5017 elsif Maybe_In_Place_OK
5018 and then Nkind (Name (Parent (N))) = N_Explicit_Dereference
5019 and then Is_Entity_Name (Prefix (Name (Parent (N))))
5021 Tmp := Name (Parent (N));
5023 if Etype (Tmp) /= Etype (N) then
5024 Apply_Length_Check (N, Etype (Tmp));
5027 elsif Maybe_In_Place_OK
5028 and then Nkind (Name (Parent (N))) = N_Slice
5029 and then Safe_Slice_Assignment (N)
5031 -- Safe_Slice_Assignment rewrites assignment as a loop
5037 -- In place aggregate expansion is not possible
5040 Maybe_In_Place_OK := False;
5041 Tmp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
5043 Make_Object_Declaration
5045 Defining_Identifier => Tmp,
5046 Object_Definition => New_Occurrence_Of (Typ, Loc));
5047 Set_No_Initialization (Tmp_Decl, True);
5049 -- If we are within a loop, the temporary will be pushed on the
5050 -- stack at each iteration. If the aggregate is the expression for
5051 -- an allocator, it will be immediately copied to the heap and can
5052 -- be reclaimed at once. We create a transient scope around the
5053 -- aggregate for this purpose.
5055 if Ekind (Current_Scope) = E_Loop
5056 and then Nkind (Parent (Parent (N))) = N_Allocator
5058 Establish_Transient_Scope (N, False);
5061 Insert_Action (N, Tmp_Decl);
5064 -- Construct and insert the aggregate code. We can safely suppress
5065 -- index checks because this code is guaranteed not to raise CE
5066 -- on index checks. However we should *not* suppress all checks.
5072 if Nkind (Tmp) = N_Defining_Identifier then
5073 Target := New_Reference_To (Tmp, Loc);
5077 if Has_Default_Init_Comps (N) then
5079 -- Ada 2005 (AI-287): This case has not been analyzed???
5081 raise Program_Error;
5084 -- Name in assignment is explicit dereference
5086 Target := New_Copy (Tmp);
5090 Build_Array_Aggr_Code (N,
5092 Index => First_Index (Typ),
5094 Scalar_Comp => Is_Scalar_Type (Ctyp));
5097 if Comes_From_Source (Tmp) then
5098 Insert_Actions_After (Parent (N), Aggr_Code);
5101 Insert_Actions (N, Aggr_Code);
5104 -- If the aggregate has been assigned in place, remove the original
5107 if Nkind (Parent (N)) = N_Assignment_Statement
5108 and then Maybe_In_Place_OK
5110 Rewrite (Parent (N), Make_Null_Statement (Loc));
5112 elsif Nkind (Parent (N)) /= N_Object_Declaration
5113 or else Tmp /= Defining_Identifier (Parent (N))
5115 Rewrite (N, New_Occurrence_Of (Tmp, Loc));
5116 Analyze_And_Resolve (N, Typ);
5118 end Expand_Array_Aggregate;
5120 ------------------------
5121 -- Expand_N_Aggregate --
5122 ------------------------
5124 procedure Expand_N_Aggregate (N : Node_Id) is
5126 if Is_Record_Type (Etype (N)) then
5127 Expand_Record_Aggregate (N);
5129 Expand_Array_Aggregate (N);
5132 when RE_Not_Available =>
5134 end Expand_N_Aggregate;
5136 ----------------------------------
5137 -- Expand_N_Extension_Aggregate --
5138 ----------------------------------
5140 -- If the ancestor part is an expression, add a component association for
5141 -- the parent field. If the type of the ancestor part is not the direct
5142 -- parent of the expected type, build recursively the needed ancestors.
5143 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
5144 -- ration for a temporary of the expected type, followed by individual
5145 -- assignments to the given components.
5147 procedure Expand_N_Extension_Aggregate (N : Node_Id) is
5148 Loc : constant Source_Ptr := Sloc (N);
5149 A : constant Node_Id := Ancestor_Part (N);
5150 Typ : constant Entity_Id := Etype (N);
5153 -- If the ancestor is a subtype mark, an init proc must be called
5154 -- on the resulting object which thus has to be materialized in
5157 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
5158 Convert_To_Assignments (N, Typ);
5160 -- The extension aggregate is transformed into a record aggregate
5161 -- of the following form (c1 and c2 are inherited components)
5163 -- (Exp with c3 => a, c4 => b)
5164 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c1 => a, c2 => b)
5169 if VM_Target = No_VM then
5170 Expand_Record_Aggregate (N,
5173 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc),
5176 -- No tag is needed in the case of a VM
5177 Expand_Record_Aggregate (N,
5183 when RE_Not_Available =>
5185 end Expand_N_Extension_Aggregate;
5187 -----------------------------
5188 -- Expand_Record_Aggregate --
5189 -----------------------------
5191 procedure Expand_Record_Aggregate
5193 Orig_Tag : Node_Id := Empty;
5194 Parent_Expr : Node_Id := Empty)
5196 Loc : constant Source_Ptr := Sloc (N);
5197 Comps : constant List_Id := Component_Associations (N);
5198 Typ : constant Entity_Id := Etype (N);
5199 Base_Typ : constant Entity_Id := Base_Type (Typ);
5201 Static_Components : Boolean := True;
5202 -- Flag to indicate whether all components are compile-time known,
5203 -- and the aggregate can be constructed statically and handled by
5206 function Component_Not_OK_For_Backend return Boolean;
5207 -- Check for presence of component which makes it impossible for the
5208 -- backend to process the aggregate, thus requiring the use of a series
5209 -- of assignment statements. Cases checked for are a nested aggregate
5210 -- needing Late_Expansion, the presence of a tagged component which may
5211 -- need tag adjustment, and a bit unaligned component reference.
5213 -- We also force expansion into assignments if a component is of a
5214 -- mutable type (including a private type with discriminants) because
5215 -- in that case the size of the component to be copied may be smaller
5216 -- than the side of the target, and there is no simple way for gigi
5217 -- to compute the size of the object to be copied.
5219 -- NOTE: This is part of the ongoing work to define precisely the
5220 -- interface between front-end and back-end handling of aggregates.
5221 -- In general it is desirable to pass aggregates as they are to gigi,
5222 -- in order to minimize elaboration code. This is one case where the
5223 -- semantics of Ada complicate the analysis and lead to anomalies in
5224 -- the gcc back-end if the aggregate is not expanded into assignments.
5226 ----------------------------------
5227 -- Component_Not_OK_For_Backend --
5228 ----------------------------------
5230 function Component_Not_OK_For_Backend return Boolean is
5240 while Present (C) loop
5241 if Nkind (Expression (C)) = N_Qualified_Expression then
5242 Expr_Q := Expression (Expression (C));
5244 Expr_Q := Expression (C);
5247 -- Return true if the aggregate has any associations for tagged
5248 -- components that may require tag adjustment.
5250 -- These are cases where the source expression may have a tag that
5251 -- could differ from the component tag (e.g., can occur for type
5252 -- conversions and formal parameters). (Tag adjustment not needed
5253 -- if VM_Target because object tags are implicit in the machine.)
5255 if Is_Tagged_Type (Etype (Expr_Q))
5256 and then (Nkind (Expr_Q) = N_Type_Conversion
5257 or else (Is_Entity_Name (Expr_Q)
5259 Ekind (Entity (Expr_Q)) in Formal_Kind))
5260 and then VM_Target = No_VM
5262 Static_Components := False;
5265 elsif Is_Delayed_Aggregate (Expr_Q) then
5266 Static_Components := False;
5269 elsif Possible_Bit_Aligned_Component (Expr_Q) then
5270 Static_Components := False;
5274 if Is_Scalar_Type (Etype (Expr_Q)) then
5275 if not Compile_Time_Known_Value (Expr_Q) then
5276 Static_Components := False;
5279 elsif Nkind (Expr_Q) /= N_Aggregate
5280 or else not Compile_Time_Known_Aggregate (Expr_Q)
5282 Static_Components := False;
5284 if Is_Private_Type (Etype (Expr_Q))
5285 and then Has_Discriminants (Etype (Expr_Q))
5295 end Component_Not_OK_For_Backend;
5297 -- Remaining Expand_Record_Aggregate variables
5299 Tag_Value : Node_Id;
5303 -- Start of processing for Expand_Record_Aggregate
5306 -- If the aggregate is to be assigned to an atomic variable, we
5307 -- have to prevent a piecemeal assignment even if the aggregate
5308 -- is to be expanded. We create a temporary for the aggregate, and
5309 -- assign the temporary instead, so that the back end can generate
5310 -- an atomic move for it.
5313 and then (Nkind (Parent (N)) = N_Object_Declaration
5314 or else Nkind (Parent (N)) = N_Assignment_Statement)
5315 and then Comes_From_Source (Parent (N))
5317 Expand_Atomic_Aggregate (N, Typ);
5320 -- No special management required for aggregates used to initialize
5321 -- statically allocated dispatch tables
5323 elsif Is_Static_Dispatch_Table_Aggregate (N) then
5327 -- Ada 2005 (AI-318-2): We need to convert to assignments if components
5328 -- are build-in-place function calls. This test could be more specific,
5329 -- but doing it for all inherently limited aggregates seems harmless.
5330 -- The assignments will turn into build-in-place function calls (see
5331 -- Make_Build_In_Place_Call_In_Assignment).
5333 if Ada_Version >= Ada_05 and then Is_Inherently_Limited_Type (Typ) then
5334 Convert_To_Assignments (N, Typ);
5336 -- Gigi doesn't handle properly temporaries of variable size
5337 -- so we generate it in the front-end
5339 elsif not Size_Known_At_Compile_Time (Typ) then
5340 Convert_To_Assignments (N, Typ);
5342 -- Temporaries for controlled aggregates need to be attached to a
5343 -- final chain in order to be properly finalized, so it has to
5344 -- be created in the front-end
5346 elsif Is_Controlled (Typ)
5347 or else Has_Controlled_Component (Base_Type (Typ))
5349 Convert_To_Assignments (N, Typ);
5351 -- Ada 2005 (AI-287): In case of default initialized components we
5352 -- convert the aggregate into assignments.
5354 elsif Has_Default_Init_Comps (N) then
5355 Convert_To_Assignments (N, Typ);
5359 elsif Component_Not_OK_For_Backend then
5360 Convert_To_Assignments (N, Typ);
5362 -- If an ancestor is private, some components are not inherited and
5363 -- we cannot expand into a record aggregate
5365 elsif Has_Private_Ancestor (Typ) then
5366 Convert_To_Assignments (N, Typ);
5368 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
5369 -- is not able to handle the aggregate for Late_Request.
5371 elsif Is_Tagged_Type (Typ) and then Has_Discriminants (Typ) then
5372 Convert_To_Assignments (N, Typ);
5374 -- If the tagged types covers interface types we need to initialize all
5375 -- hidden components containing pointers to secondary dispatch tables.
5377 elsif Is_Tagged_Type (Typ) and then Has_Abstract_Interfaces (Typ) then
5378 Convert_To_Assignments (N, Typ);
5380 -- If some components are mutable, the size of the aggregate component
5381 -- may be distinct from the default size of the type component, so
5382 -- we need to expand to insure that the back-end copies the proper
5383 -- size of the data.
5385 elsif Has_Mutable_Components (Typ) then
5386 Convert_To_Assignments (N, Typ);
5388 -- If the type involved has any non-bit aligned components, then we are
5389 -- not sure that the back end can handle this case correctly.
5391 elsif Type_May_Have_Bit_Aligned_Components (Typ) then
5392 Convert_To_Assignments (N, Typ);
5394 -- In all other cases, build a proper aggregate handlable by gigi
5397 if Nkind (N) = N_Aggregate then
5399 -- If the aggregate is static and can be handled by the back-end,
5400 -- nothing left to do.
5402 if Static_Components then
5403 Set_Compile_Time_Known_Aggregate (N);
5404 Set_Expansion_Delayed (N, False);
5408 -- If no discriminants, nothing special to do
5410 if not Has_Discriminants (Typ) then
5413 -- Case of discriminants present
5415 elsif Is_Derived_Type (Typ) then
5417 -- For untagged types, non-stored discriminants are replaced
5418 -- with stored discriminants, which are the ones that gigi uses
5419 -- to describe the type and its components.
5421 Generate_Aggregate_For_Derived_Type : declare
5422 Constraints : constant List_Id := New_List;
5423 First_Comp : Node_Id;
5424 Discriminant : Entity_Id;
5426 Num_Disc : Int := 0;
5427 Num_Gird : Int := 0;
5429 procedure Prepend_Stored_Values (T : Entity_Id);
5430 -- Scan the list of stored discriminants of the type, and add
5431 -- their values to the aggregate being built.
5433 ---------------------------
5434 -- Prepend_Stored_Values --
5435 ---------------------------
5437 procedure Prepend_Stored_Values (T : Entity_Id) is
5439 Discriminant := First_Stored_Discriminant (T);
5440 while Present (Discriminant) loop
5442 Make_Component_Association (Loc,
5444 New_List (New_Occurrence_Of (Discriminant, Loc)),
5448 Get_Discriminant_Value (
5451 Discriminant_Constraint (Typ))));
5453 if No (First_Comp) then
5454 Prepend_To (Component_Associations (N), New_Comp);
5456 Insert_After (First_Comp, New_Comp);
5459 First_Comp := New_Comp;
5460 Next_Stored_Discriminant (Discriminant);
5462 end Prepend_Stored_Values;
5464 -- Start of processing for Generate_Aggregate_For_Derived_Type
5467 -- Remove the associations for the discriminant of derived type
5469 First_Comp := First (Component_Associations (N));
5470 while Present (First_Comp) loop
5475 (First (Choices (Comp)))) = E_Discriminant
5478 Num_Disc := Num_Disc + 1;
5482 -- Insert stored discriminant associations in the correct
5483 -- order. If there are more stored discriminants than new
5484 -- discriminants, there is at least one new discriminant that
5485 -- constrains more than one of the stored discriminants. In
5486 -- this case we need to construct a proper subtype of the
5487 -- parent type, in order to supply values to all the
5488 -- components. Otherwise there is one-one correspondence
5489 -- between the constraints and the stored discriminants.
5491 First_Comp := Empty;
5493 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
5494 while Present (Discriminant) loop
5495 Num_Gird := Num_Gird + 1;
5496 Next_Stored_Discriminant (Discriminant);
5499 -- Case of more stored discriminants than new discriminants
5501 if Num_Gird > Num_Disc then
5503 -- Create a proper subtype of the parent type, which is the
5504 -- proper implementation type for the aggregate, and convert
5505 -- it to the intended target type.
5507 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
5508 while Present (Discriminant) loop
5511 Get_Discriminant_Value (
5514 Discriminant_Constraint (Typ)));
5515 Append (New_Comp, Constraints);
5516 Next_Stored_Discriminant (Discriminant);
5520 Make_Subtype_Declaration (Loc,
5521 Defining_Identifier =>
5522 Make_Defining_Identifier (Loc,
5523 New_Internal_Name ('T')),
5524 Subtype_Indication =>
5525 Make_Subtype_Indication (Loc,
5527 New_Occurrence_Of (Etype (Base_Type (Typ)), Loc),
5529 Make_Index_Or_Discriminant_Constraint
5530 (Loc, Constraints)));
5532 Insert_Action (N, Decl);
5533 Prepend_Stored_Values (Base_Type (Typ));
5535 Set_Etype (N, Defining_Identifier (Decl));
5538 Rewrite (N, Unchecked_Convert_To (Typ, N));
5541 -- Case where we do not have fewer new discriminants than
5542 -- stored discriminants, so in this case we can simply use the
5543 -- stored discriminants of the subtype.
5546 Prepend_Stored_Values (Typ);
5548 end Generate_Aggregate_For_Derived_Type;
5551 if Is_Tagged_Type (Typ) then
5553 -- The tagged case, _parent and _tag component must be created
5555 -- Reset null_present unconditionally. tagged records always have
5556 -- at least one field (the tag or the parent)
5558 Set_Null_Record_Present (N, False);
5560 -- When the current aggregate comes from the expansion of an
5561 -- extension aggregate, the parent expr is replaced by an
5562 -- aggregate formed by selected components of this expr
5564 if Present (Parent_Expr)
5565 and then Is_Empty_List (Comps)
5567 Comp := First_Component_Or_Discriminant (Typ);
5568 while Present (Comp) loop
5570 -- Skip all expander-generated components
5573 not Comes_From_Source (Original_Record_Component (Comp))
5579 Make_Selected_Component (Loc,
5581 Unchecked_Convert_To (Typ,
5582 Duplicate_Subexpr (Parent_Expr, True)),
5584 Selector_Name => New_Occurrence_Of (Comp, Loc));
5587 Make_Component_Association (Loc,
5589 New_List (New_Occurrence_Of (Comp, Loc)),
5593 Analyze_And_Resolve (New_Comp, Etype (Comp));
5596 Next_Component_Or_Discriminant (Comp);
5600 -- Compute the value for the Tag now, if the type is a root it
5601 -- will be included in the aggregate right away, otherwise it will
5602 -- be propagated to the parent aggregate
5604 if Present (Orig_Tag) then
5605 Tag_Value := Orig_Tag;
5606 elsif VM_Target /= No_VM then
5611 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc);
5614 -- For a derived type, an aggregate for the parent is formed with
5615 -- all the inherited components.
5617 if Is_Derived_Type (Typ) then
5620 First_Comp : Node_Id;
5621 Parent_Comps : List_Id;
5622 Parent_Aggr : Node_Id;
5623 Parent_Name : Node_Id;
5626 -- Remove the inherited component association from the
5627 -- aggregate and store them in the parent aggregate
5629 First_Comp := First (Component_Associations (N));
5630 Parent_Comps := New_List;
5631 while Present (First_Comp)
5632 and then Scope (Original_Record_Component (
5633 Entity (First (Choices (First_Comp))))) /= Base_Typ
5638 Append (Comp, Parent_Comps);
5641 Parent_Aggr := Make_Aggregate (Loc,
5642 Component_Associations => Parent_Comps);
5643 Set_Etype (Parent_Aggr, Etype (Base_Type (Typ)));
5645 -- Find the _parent component
5647 Comp := First_Component (Typ);
5648 while Chars (Comp) /= Name_uParent loop
5649 Comp := Next_Component (Comp);
5652 Parent_Name := New_Occurrence_Of (Comp, Loc);
5654 -- Insert the parent aggregate
5656 Prepend_To (Component_Associations (N),
5657 Make_Component_Association (Loc,
5658 Choices => New_List (Parent_Name),
5659 Expression => Parent_Aggr));
5661 -- Expand recursively the parent propagating the right Tag
5663 Expand_Record_Aggregate (
5664 Parent_Aggr, Tag_Value, Parent_Expr);
5667 -- For a root type, the tag component is added (unless compiling
5668 -- for the VMs, where tags are implicit).
5670 elsif VM_Target = No_VM then
5672 Tag_Name : constant Node_Id :=
5674 (First_Tag_Component (Typ), Loc);
5675 Typ_Tag : constant Entity_Id := RTE (RE_Tag);
5676 Conv_Node : constant Node_Id :=
5677 Unchecked_Convert_To (Typ_Tag, Tag_Value);
5680 Set_Etype (Conv_Node, Typ_Tag);
5681 Prepend_To (Component_Associations (N),
5682 Make_Component_Association (Loc,
5683 Choices => New_List (Tag_Name),
5684 Expression => Conv_Node));
5690 end Expand_Record_Aggregate;
5692 ----------------------------
5693 -- Has_Default_Init_Comps --
5694 ----------------------------
5696 function Has_Default_Init_Comps (N : Node_Id) return Boolean is
5697 Comps : constant List_Id := Component_Associations (N);
5701 pragma Assert (Nkind (N) = N_Aggregate
5702 or else Nkind (N) = N_Extension_Aggregate);
5708 if Has_Self_Reference (N) then
5712 -- Check if any direct component has default initialized components
5715 while Present (C) loop
5716 if Box_Present (C) then
5723 -- Recursive call in case of aggregate expression
5726 while Present (C) loop
5727 Expr := Expression (C);
5730 and then (Nkind (Expr) = N_Aggregate
5731 or else Nkind (Expr) = N_Extension_Aggregate)
5732 and then Has_Default_Init_Comps (Expr)
5741 end Has_Default_Init_Comps;
5743 --------------------------
5744 -- Is_Delayed_Aggregate --
5745 --------------------------
5747 function Is_Delayed_Aggregate (N : Node_Id) return Boolean is
5748 Node : Node_Id := N;
5749 Kind : Node_Kind := Nkind (Node);
5752 if Kind = N_Qualified_Expression then
5753 Node := Expression (Node);
5754 Kind := Nkind (Node);
5757 if Kind /= N_Aggregate and then Kind /= N_Extension_Aggregate then
5760 return Expansion_Delayed (Node);
5762 end Is_Delayed_Aggregate;
5764 ----------------------------------------
5765 -- Is_Static_Dispatch_Table_Aggregate --
5766 ----------------------------------------
5768 function Is_Static_Dispatch_Table_Aggregate (N : Node_Id) return Boolean is
5769 Typ : constant Entity_Id := Base_Type (Etype (N));
5772 return Static_Dispatch_Tables
5773 and then VM_Target = No_VM
5774 and then RTU_Loaded (Ada_Tags)
5776 -- Avoid circularity when rebuilding the compiler
5778 and then Cunit_Entity (Get_Source_Unit (N)) /= RTU_Entity (Ada_Tags)
5779 and then (Typ = RTE (RE_Dispatch_Table_Wrapper)
5781 Typ = RTE (RE_Address_Array)
5783 Typ = RTE (RE_Type_Specific_Data)
5785 Typ = RTE (RE_Tag_Table)
5787 (RTE_Available (RE_Interface_Data)
5788 and then Typ = RTE (RE_Interface_Data))
5790 (RTE_Available (RE_Interfaces_Array)
5791 and then Typ = RTE (RE_Interfaces_Array))
5793 (RTE_Available (RE_Interface_Data_Element)
5794 and then Typ = RTE (RE_Interface_Data_Element)));
5795 end Is_Static_Dispatch_Table_Aggregate;
5797 --------------------
5798 -- Late_Expansion --
5799 --------------------
5801 function Late_Expansion
5805 Flist : Node_Id := Empty;
5806 Obj : Entity_Id := Empty) return List_Id
5809 if Is_Record_Type (Etype (N)) then
5810 return Build_Record_Aggr_Code (N, Typ, Target, Flist, Obj);
5812 else pragma Assert (Is_Array_Type (Etype (N)));
5814 Build_Array_Aggr_Code
5816 Ctype => Component_Type (Etype (N)),
5817 Index => First_Index (Typ),
5819 Scalar_Comp => Is_Scalar_Type (Component_Type (Typ)),
5825 ----------------------------------
5826 -- Make_OK_Assignment_Statement --
5827 ----------------------------------
5829 function Make_OK_Assignment_Statement
5832 Expression : Node_Id) return Node_Id
5835 Set_Assignment_OK (Name);
5837 return Make_Assignment_Statement (Sloc, Name, Expression);
5838 end Make_OK_Assignment_Statement;
5840 -----------------------
5841 -- Number_Of_Choices --
5842 -----------------------
5844 function Number_Of_Choices (N : Node_Id) return Nat is
5848 Nb_Choices : Nat := 0;
5851 if Present (Expressions (N)) then
5855 Assoc := First (Component_Associations (N));
5856 while Present (Assoc) loop
5857 Choice := First (Choices (Assoc));
5858 while Present (Choice) loop
5859 if Nkind (Choice) /= N_Others_Choice then
5860 Nb_Choices := Nb_Choices + 1;
5870 end Number_Of_Choices;
5872 ------------------------------------
5873 -- Packed_Array_Aggregate_Handled --
5874 ------------------------------------
5876 -- The current version of this procedure will handle at compile time
5877 -- any array aggregate that meets these conditions:
5879 -- One dimensional, bit packed
5880 -- Underlying packed type is modular type
5881 -- Bounds are within 32-bit Int range
5882 -- All bounds and values are static
5884 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean is
5885 Loc : constant Source_Ptr := Sloc (N);
5886 Typ : constant Entity_Id := Etype (N);
5887 Ctyp : constant Entity_Id := Component_Type (Typ);
5889 Not_Handled : exception;
5890 -- Exception raised if this aggregate cannot be handled
5893 -- For now, handle only one dimensional bit packed arrays
5895 if not Is_Bit_Packed_Array (Typ)
5896 or else Number_Dimensions (Typ) > 1
5897 or else not Is_Modular_Integer_Type (Packed_Array_Type (Typ))
5902 if not Is_Scalar_Type (Component_Type (Typ))
5903 and then Has_Non_Standard_Rep (Component_Type (Typ))
5909 Csiz : constant Nat := UI_To_Int (Component_Size (Typ));
5913 -- Bounds of index type
5917 -- Values of bounds if compile time known
5919 function Get_Component_Val (N : Node_Id) return Uint;
5920 -- Given a expression value N of the component type Ctyp, returns a
5921 -- value of Csiz (component size) bits representing this value. If
5922 -- the value is non-static or any other reason exists why the value
5923 -- cannot be returned, then Not_Handled is raised.
5925 -----------------------
5926 -- Get_Component_Val --
5927 -----------------------
5929 function Get_Component_Val (N : Node_Id) return Uint is
5933 -- We have to analyze the expression here before doing any further
5934 -- processing here. The analysis of such expressions is deferred
5935 -- till expansion to prevent some problems of premature analysis.
5937 Analyze_And_Resolve (N, Ctyp);
5939 -- Must have a compile time value. String literals have to be
5940 -- converted into temporaries as well, because they cannot easily
5941 -- be converted into their bit representation.
5943 if not Compile_Time_Known_Value (N)
5944 or else Nkind (N) = N_String_Literal
5949 Val := Expr_Rep_Value (N);
5951 -- Adjust for bias, and strip proper number of bits
5953 if Has_Biased_Representation (Ctyp) then
5954 Val := Val - Expr_Value (Type_Low_Bound (Ctyp));
5957 return Val mod Uint_2 ** Csiz;
5958 end Get_Component_Val;
5960 -- Here we know we have a one dimensional bit packed array
5963 Get_Index_Bounds (First_Index (Typ), Lo, Hi);
5965 -- Cannot do anything if bounds are dynamic
5967 if not Compile_Time_Known_Value (Lo)
5969 not Compile_Time_Known_Value (Hi)
5974 -- Or are silly out of range of int bounds
5976 Lob := Expr_Value (Lo);
5977 Hib := Expr_Value (Hi);
5979 if not UI_Is_In_Int_Range (Lob)
5981 not UI_Is_In_Int_Range (Hib)
5986 -- At this stage we have a suitable aggregate for handling at compile
5987 -- time (the only remaining checks are that the values of expressions
5988 -- in the aggregate are compile time known (check is performed by
5989 -- Get_Component_Val), and that any subtypes or ranges are statically
5992 -- If the aggregate is not fully positional at this stage, then
5993 -- convert it to positional form. Either this will fail, in which
5994 -- case we can do nothing, or it will succeed, in which case we have
5995 -- succeeded in handling the aggregate, or it will stay an aggregate,
5996 -- in which case we have failed to handle this case.
5998 if Present (Component_Associations (N)) then
5999 Convert_To_Positional
6000 (N, Max_Others_Replicate => 64, Handle_Bit_Packed => True);
6001 return Nkind (N) /= N_Aggregate;
6004 -- Otherwise we are all positional, so convert to proper value
6007 Lov : constant Int := UI_To_Int (Lob);
6008 Hiv : constant Int := UI_To_Int (Hib);
6010 Len : constant Nat := Int'Max (0, Hiv - Lov + 1);
6011 -- The length of the array (number of elements)
6013 Aggregate_Val : Uint;
6014 -- Value of aggregate. The value is set in the low order bits of
6015 -- this value. For the little-endian case, the values are stored
6016 -- from low-order to high-order and for the big-endian case the
6017 -- values are stored from high-order to low-order. Note that gigi
6018 -- will take care of the conversions to left justify the value in
6019 -- the big endian case (because of left justified modular type
6020 -- processing), so we do not have to worry about that here.
6023 -- Integer literal for resulting constructed value
6026 -- Shift count from low order for next value
6029 -- Shift increment for loop
6032 -- Next expression from positional parameters of aggregate
6035 -- For little endian, we fill up the low order bits of the target
6036 -- value. For big endian we fill up the high order bits of the
6037 -- target value (which is a left justified modular value).
6039 if Bytes_Big_Endian xor Debug_Flag_8 then
6040 Shift := Csiz * (Len - 1);
6047 -- Loop to set the values
6050 Aggregate_Val := Uint_0;
6052 Expr := First (Expressions (N));
6053 Aggregate_Val := Get_Component_Val (Expr) * Uint_2 ** Shift;
6055 for J in 2 .. Len loop
6056 Shift := Shift + Incr;
6059 Aggregate_Val + Get_Component_Val (Expr) * Uint_2 ** Shift;
6063 -- Now we can rewrite with the proper value
6066 Make_Integer_Literal (Loc,
6067 Intval => Aggregate_Val);
6068 Set_Print_In_Hex (Lit);
6070 -- Construct the expression using this literal. Note that it is
6071 -- important to qualify the literal with its proper modular type
6072 -- since universal integer does not have the required range and
6073 -- also this is a left justified modular type, which is important
6074 -- in the big-endian case.
6077 Unchecked_Convert_To (Typ,
6078 Make_Qualified_Expression (Loc,
6080 New_Occurrence_Of (Packed_Array_Type (Typ), Loc),
6081 Expression => Lit)));
6083 Analyze_And_Resolve (N, Typ);
6091 end Packed_Array_Aggregate_Handled;
6093 ----------------------------
6094 -- Has_Mutable_Components --
6095 ----------------------------
6097 function Has_Mutable_Components (Typ : Entity_Id) return Boolean is
6101 Comp := First_Component (Typ);
6102 while Present (Comp) loop
6103 if Is_Record_Type (Etype (Comp))
6104 and then Has_Discriminants (Etype (Comp))
6105 and then not Is_Constrained (Etype (Comp))
6110 Next_Component (Comp);
6114 end Has_Mutable_Components;
6116 ------------------------------
6117 -- Initialize_Discriminants --
6118 ------------------------------
6120 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id) is
6121 Loc : constant Source_Ptr := Sloc (N);
6122 Bas : constant Entity_Id := Base_Type (Typ);
6123 Par : constant Entity_Id := Etype (Bas);
6124 Decl : constant Node_Id := Parent (Par);
6128 if Is_Tagged_Type (Bas)
6129 and then Is_Derived_Type (Bas)
6130 and then Has_Discriminants (Par)
6131 and then Has_Discriminants (Bas)
6132 and then Number_Discriminants (Bas) /= Number_Discriminants (Par)
6133 and then Nkind (Decl) = N_Full_Type_Declaration
6134 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
6136 (Variant_Part (Component_List (Type_Definition (Decl))))
6137 and then Nkind (N) /= N_Extension_Aggregate
6140 -- Call init proc to set discriminants.
6141 -- There should eventually be a special procedure for this ???
6143 Ref := New_Reference_To (Defining_Identifier (N), Loc);
6144 Insert_Actions_After (N,
6145 Build_Initialization_Call (Sloc (N), Ref, Typ));
6147 end Initialize_Discriminants;
6154 (Obj_Type : Entity_Id;
6155 Typ : Entity_Id) return Boolean
6157 L1, L2, H1, H2 : Node_Id;
6159 -- No sliding if the type of the object is not established yet, if it is
6160 -- an unconstrained type whose actual subtype comes from the aggregate,
6161 -- or if the two types are identical.
6163 if not Is_Array_Type (Obj_Type) then
6166 elsif not Is_Constrained (Obj_Type) then
6169 elsif Typ = Obj_Type then
6173 -- Sliding can only occur along the first dimension
6175 Get_Index_Bounds (First_Index (Typ), L1, H1);
6176 Get_Index_Bounds (First_Index (Obj_Type), L2, H2);
6178 if not Is_Static_Expression (L1)
6179 or else not Is_Static_Expression (L2)
6180 or else not Is_Static_Expression (H1)
6181 or else not Is_Static_Expression (H2)
6185 return Expr_Value (L1) /= Expr_Value (L2)
6186 or else Expr_Value (H1) /= Expr_Value (H2);
6191 ---------------------------
6192 -- Safe_Slice_Assignment --
6193 ---------------------------
6195 function Safe_Slice_Assignment (N : Node_Id) return Boolean is
6196 Loc : constant Source_Ptr := Sloc (Parent (N));
6197 Pref : constant Node_Id := Prefix (Name (Parent (N)));
6198 Range_Node : constant Node_Id := Discrete_Range (Name (Parent (N)));
6206 -- Generate: for J in Range loop Pref (J) := Expr; end loop;
6208 if Comes_From_Source (N)
6209 and then No (Expressions (N))
6210 and then Nkind (First (Choices (First (Component_Associations (N)))))
6214 Expression (First (Component_Associations (N)));
6215 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
6218 Make_Iteration_Scheme (Loc,
6219 Loop_Parameter_Specification =>
6220 Make_Loop_Parameter_Specification
6222 Defining_Identifier => L_J,
6223 Discrete_Subtype_Definition => Relocate_Node (Range_Node)));
6226 Make_Assignment_Statement (Loc,
6228 Make_Indexed_Component (Loc,
6229 Prefix => Relocate_Node (Pref),
6230 Expressions => New_List (New_Occurrence_Of (L_J, Loc))),
6231 Expression => Relocate_Node (Expr));
6233 -- Construct the final loop
6236 Make_Implicit_Loop_Statement
6237 (Node => Parent (N),
6238 Identifier => Empty,
6239 Iteration_Scheme => L_Iter,
6240 Statements => New_List (L_Body));
6242 -- Set type of aggregate to be type of lhs in assignment,
6243 -- to suppress redundant length checks.
6245 Set_Etype (N, Etype (Name (Parent (N))));
6247 Rewrite (Parent (N), Stat);
6248 Analyze (Parent (N));
6254 end Safe_Slice_Assignment;
6256 ---------------------
6257 -- Sort_Case_Table --
6258 ---------------------
6260 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
6261 L : constant Int := Case_Table'First;
6262 U : constant Int := Case_Table'Last;
6270 T := Case_Table (K + 1);
6274 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
6275 Expr_Value (T.Choice_Lo)
6277 Case_Table (J) := Case_Table (J - 1);
6281 Case_Table (J) := T;
6284 end Sort_Case_Table;
6286 ----------------------------
6287 -- Static_Array_Aggregate --
6288 ----------------------------
6290 function Static_Array_Aggregate (N : Node_Id) return Boolean is
6291 Bounds : constant Node_Id := Aggregate_Bounds (N);
6293 Typ : constant Entity_Id := Etype (N);
6294 Comp_Type : constant Entity_Id := Component_Type (Typ);
6301 if Is_Tagged_Type (Typ)
6302 or else Is_Controlled (Typ)
6303 or else Is_Packed (Typ)
6309 and then Nkind (Bounds) = N_Range
6310 and then Nkind (Low_Bound (Bounds)) = N_Integer_Literal
6311 and then Nkind (High_Bound (Bounds)) = N_Integer_Literal
6313 Lo := Low_Bound (Bounds);
6314 Hi := High_Bound (Bounds);
6316 if No (Component_Associations (N)) then
6318 -- Verify that all components are static integers
6320 Expr := First (Expressions (N));
6321 while Present (Expr) loop
6322 if Nkind (Expr) /= N_Integer_Literal then
6332 -- We allow only a single named association, either a static
6333 -- range or an others_clause, with a static expression.
6335 Expr := First (Component_Associations (N));
6337 if Present (Expressions (N)) then
6340 elsif Present (Next (Expr)) then
6343 elsif Present (Next (First (Choices (Expr)))) then
6347 -- The aggregate is static if all components are literals, or
6348 -- else all its components are static aggregates for the
6349 -- component type. We also limit the size of a static aggregate
6350 -- to prevent runaway static expressions.
6352 if Is_Array_Type (Comp_Type)
6353 or else Is_Record_Type (Comp_Type)
6355 if Nkind (Expression (Expr)) /= N_Aggregate
6357 not Compile_Time_Known_Aggregate (Expression (Expr))
6362 elsif Nkind (Expression (Expr)) /= N_Integer_Literal then
6365 elsif not Aggr_Size_OK (Typ) then
6369 -- Create a positional aggregate with the right number of
6370 -- copies of the expression.
6372 Agg := Make_Aggregate (Sloc (N), New_List, No_List);
6374 for I in UI_To_Int (Intval (Lo)) .. UI_To_Int (Intval (Hi))
6377 (Expressions (Agg), New_Copy (Expression (Expr)));
6378 Set_Etype (Last (Expressions (Agg)), Component_Type (Typ));
6381 Set_Aggregate_Bounds (Agg, Bounds);
6382 Set_Etype (Agg, Typ);
6385 Set_Compile_Time_Known_Aggregate (N);
6394 end Static_Array_Aggregate;