1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2011, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Checks; use Checks;
28 with Debug; use Debug;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Expander; use Expander;
33 with Exp_Util; use Exp_Util;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch7; use Exp_Ch7;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Disp; use Exp_Disp;
38 with Exp_Tss; use Exp_Tss;
39 with Fname; use Fname;
40 with Freeze; use Freeze;
41 with Itypes; use Itypes;
43 with Namet; use Namet;
44 with Nmake; use Nmake;
45 with Nlists; use Nlists;
47 with Restrict; use Restrict;
48 with Rident; use Rident;
49 with Rtsfind; use Rtsfind;
50 with Ttypes; use Ttypes;
52 with Sem_Aggr; use Sem_Aggr;
53 with Sem_Aux; use Sem_Aux;
54 with Sem_Ch3; use Sem_Ch3;
55 with Sem_Eval; use Sem_Eval;
56 with Sem_Res; use Sem_Res;
57 with Sem_Util; use Sem_Util;
58 with Sinfo; use Sinfo;
59 with Snames; use Snames;
60 with Stand; use Stand;
61 with Targparm; use Targparm;
62 with Tbuild; use Tbuild;
63 with Uintp; use Uintp;
65 package body Exp_Aggr is
67 type Case_Bounds is record
70 Choice_Node : Node_Id;
73 type Case_Table_Type is array (Nat range <>) of Case_Bounds;
74 -- Table type used by Check_Case_Choices procedure
77 (Obj_Type : Entity_Id;
78 Typ : Entity_Id) return Boolean;
79 -- A static array aggregate in an object declaration can in most cases be
80 -- expanded in place. The one exception is when the aggregate is given
81 -- with component associations that specify different bounds from those of
82 -- the type definition in the object declaration. In this pathological
83 -- case the aggregate must slide, and we must introduce an intermediate
84 -- temporary to hold it.
86 -- The same holds in an assignment to one-dimensional array of arrays,
87 -- when a component may be given with bounds that differ from those of the
90 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
91 -- Sort the Case Table using the Lower Bound of each Choice as the key.
92 -- A simple insertion sort is used since the number of choices in a case
93 -- statement of variant part will usually be small and probably in near
96 function Has_Default_Init_Comps (N : Node_Id) return Boolean;
97 -- N is an aggregate (record or array). Checks the presence of default
98 -- initialization (<>) in any component (Ada 2005: AI-287).
100 function Is_Static_Dispatch_Table_Aggregate (N : Node_Id) return Boolean;
101 -- Returns true if N is an aggregate used to initialize the components
102 -- of an statically allocated dispatch table.
104 ------------------------------------------------------
105 -- Local subprograms for Record Aggregate Expansion --
106 ------------------------------------------------------
108 procedure Expand_Record_Aggregate
110 Orig_Tag : Node_Id := Empty;
111 Parent_Expr : Node_Id := Empty);
112 -- This is the top level procedure for record aggregate expansion.
113 -- Expansion for record aggregates needs expand aggregates for tagged
114 -- record types. Specifically Expand_Record_Aggregate adds the Tag
115 -- field in front of the Component_Association list that was created
116 -- during resolution by Resolve_Record_Aggregate.
118 -- N is the record aggregate node.
119 -- Orig_Tag is the value of the Tag that has to be provided for this
120 -- specific aggregate. It carries the tag corresponding to the type
121 -- of the outermost aggregate during the recursive expansion
122 -- Parent_Expr is the ancestor part of the original extension
125 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id);
126 -- N is an N_Aggregate or an N_Extension_Aggregate. Typ is the type of the
127 -- aggregate (which can only be a record type, this procedure is only used
128 -- for record types). Transform the given aggregate into a sequence of
129 -- assignments performed component by component.
131 function Build_Record_Aggr_Code
135 Flist : Node_Id := Empty;
136 Obj : Entity_Id := Empty;
137 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id;
138 -- N is an N_Aggregate or an N_Extension_Aggregate. Typ is the type of the
139 -- aggregate. Target is an expression containing the location on which the
140 -- component by component assignments will take place. Returns the list of
141 -- assignments plus all other adjustments needed for tagged and controlled
142 -- types. Flist is an expression representing the finalization list on
143 -- which to attach the controlled components if any. Obj is present in the
144 -- object declaration and dynamic allocation cases, it contains an entity
145 -- that allows to know if the value being created needs to be attached to
146 -- the final list in case of pragma Finalize_Storage_Only.
149 -- The meaning of the Obj formal is extremely unclear. *What* entity
150 -- should be passed? For the object declaration case we may guess that
151 -- this is the object being declared, but what about the allocator case?
153 -- Is_Limited_Ancestor_Expansion indicates that the function has been
154 -- called recursively to expand the limited ancestor to avoid copying it.
156 function Has_Mutable_Components (Typ : Entity_Id) return Boolean;
157 -- Return true if one of the component is of a discriminated type with
158 -- defaults. An aggregate for a type with mutable components must be
159 -- expanded into individual assignments.
161 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id);
162 -- If the type of the aggregate is a type extension with renamed discrimi-
163 -- nants, we must initialize the hidden discriminants of the parent.
164 -- Otherwise, the target object must not be initialized. The discriminants
165 -- are initialized by calling the initialization procedure for the type.
166 -- This is incorrect if the initialization of other components has any
167 -- side effects. We restrict this call to the case where the parent type
168 -- has a variant part, because this is the only case where the hidden
169 -- discriminants are accessed, namely when calling discriminant checking
170 -- functions of the parent type, and when applying a stream attribute to
171 -- an object of the derived type.
173 -----------------------------------------------------
174 -- Local Subprograms for Array Aggregate Expansion --
175 -----------------------------------------------------
177 function Aggr_Size_OK (N : Node_Id; Typ : Entity_Id) return Boolean;
178 -- Very large static aggregates present problems to the back-end, and are
179 -- transformed into assignments and loops. This function verifies that the
180 -- total number of components of an aggregate is acceptable for rewriting
181 -- into a purely positional static form. Aggr_Size_OK must be called before
184 -- This function also detects and warns about one-component aggregates that
185 -- appear in a non-static context. Even if the component value is static,
186 -- such an aggregate must be expanded into an assignment.
188 procedure Convert_Array_Aggr_In_Allocator
192 -- If the aggregate appears within an allocator and can be expanded in
193 -- place, this routine generates the individual assignments to components
194 -- of the designated object. This is an optimization over the general
195 -- case, where a temporary is first created on the stack and then used to
196 -- construct the allocated object on the heap.
198 procedure Convert_To_Positional
200 Max_Others_Replicate : Nat := 5;
201 Handle_Bit_Packed : Boolean := False);
202 -- If possible, convert named notation to positional notation. This
203 -- conversion is possible only in some static cases. If the conversion is
204 -- possible, then N is rewritten with the analyzed converted aggregate.
205 -- The parameter Max_Others_Replicate controls the maximum number of
206 -- values corresponding to an others choice that will be converted to
207 -- positional notation (the default of 5 is the normal limit, and reflects
208 -- the fact that normally the loop is better than a lot of separate
209 -- assignments). Note that this limit gets overridden in any case if
210 -- either of the restrictions No_Elaboration_Code or No_Implicit_Loops is
211 -- set. The parameter Handle_Bit_Packed is usually set False (since we do
212 -- not expect the back end to handle bit packed arrays, so the normal case
213 -- of conversion is pointless), but in the special case of a call from
214 -- Packed_Array_Aggregate_Handled, we set this parameter to True, since
215 -- these are cases we handle in there.
217 procedure Expand_Array_Aggregate (N : Node_Id);
218 -- This is the top-level routine to perform array aggregate expansion.
219 -- N is the N_Aggregate node to be expanded.
221 function Backend_Processing_Possible (N : Node_Id) return Boolean;
222 -- This function checks if array aggregate N can be processed directly
223 -- by the backend. If this is the case True is returned.
225 function Build_Array_Aggr_Code
230 Scalar_Comp : Boolean;
231 Indexes : List_Id := No_List;
232 Flist : Node_Id := Empty) return List_Id;
233 -- This recursive routine returns a list of statements containing the
234 -- loops and assignments that are needed for the expansion of the array
237 -- N is the (sub-)aggregate node to be expanded into code. This node
238 -- has been fully analyzed, and its Etype is properly set.
240 -- Index is the index node corresponding to the array sub-aggregate N.
242 -- Into is the target expression into which we are copying the aggregate.
243 -- Note that this node may not have been analyzed yet, and so the Etype
244 -- field may not be set.
246 -- Scalar_Comp is True if the component type of the aggregate is scalar.
248 -- Indexes is the current list of expressions used to index the
249 -- object we are writing into.
251 -- Flist is an expression representing the finalization list on which
252 -- to attach the controlled components if any.
254 function Number_Of_Choices (N : Node_Id) return Nat;
255 -- Returns the number of discrete choices (not including the others choice
256 -- if present) contained in (sub-)aggregate N.
258 function Late_Expansion
262 Flist : Node_Id := Empty;
263 Obj : Entity_Id := Empty) return List_Id;
264 -- N is a nested (record or array) aggregate that has been marked with
265 -- 'Delay_Expansion'. Typ is the expected type of the aggregate and Target
266 -- is a (duplicable) expression that will hold the result of the aggregate
267 -- expansion. Flist is the finalization list to be used to attach
268 -- controlled components. 'Obj' when non empty, carries the original
269 -- object being initialized in order to know if it needs to be attached to
270 -- the previous parameter which may not be the case in the case where
271 -- Finalize_Storage_Only is set. Basically this procedure is used to
272 -- implement top-down expansions of nested aggregates. This is necessary
273 -- for avoiding temporaries at each level as well as for propagating the
274 -- right internal finalization list.
276 function Make_OK_Assignment_Statement
279 Expression : Node_Id) return Node_Id;
280 -- This is like Make_Assignment_Statement, except that Assignment_OK
281 -- is set in the left operand. All assignments built by this unit
282 -- use this routine. This is needed to deal with assignments to
283 -- initialized constants that are done in place.
285 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean;
286 -- Given an array aggregate, this function handles the case of a packed
287 -- array aggregate with all constant values, where the aggregate can be
288 -- evaluated at compile time. If this is possible, then N is rewritten
289 -- to be its proper compile time value with all the components properly
290 -- assembled. The expression is analyzed and resolved and True is
291 -- returned. If this transformation is not possible, N is unchanged
292 -- and False is returned
294 function Safe_Slice_Assignment (N : Node_Id) return Boolean;
295 -- If a slice assignment has an aggregate with a single others_choice,
296 -- the assignment can be done in place even if bounds are not static,
297 -- by converting it into a loop over the discrete range of the slice.
303 function Aggr_Size_OK (N : Node_Id; Typ : Entity_Id) return Boolean is
311 -- The following constant determines the maximum size of an array
312 -- aggregate produced by converting named to positional notation (e.g.
313 -- from others clauses). This avoids running away with attempts to
314 -- convert huge aggregates, which hit memory limits in the backend.
316 -- The normal limit is 5000, but we increase this limit to 2**24 (about
317 -- 16 million) if Restrictions (No_Elaboration_Code) or Restrictions
318 -- (No_Implicit_Loops) is specified, since in either case, we are at
319 -- risk of declaring the program illegal because of this limit.
321 Max_Aggr_Size : constant Nat :=
322 5000 + (2 ** 24 - 5000) *
324 (Restriction_Active (No_Elaboration_Code)
326 Restriction_Active (No_Implicit_Loops));
328 function Component_Count (T : Entity_Id) return Int;
329 -- The limit is applied to the total number of components that the
330 -- aggregate will have, which is the number of static expressions
331 -- that will appear in the flattened array. This requires a recursive
332 -- computation of the number of scalar components of the structure.
334 ---------------------
335 -- Component_Count --
336 ---------------------
338 function Component_Count (T : Entity_Id) return Int is
343 if Is_Scalar_Type (T) then
346 elsif Is_Record_Type (T) then
347 Comp := First_Component (T);
348 while Present (Comp) loop
349 Res := Res + Component_Count (Etype (Comp));
350 Next_Component (Comp);
355 elsif Is_Array_Type (T) then
357 Lo : constant Node_Id :=
358 Type_Low_Bound (Etype (First_Index (T)));
359 Hi : constant Node_Id :=
360 Type_High_Bound (Etype (First_Index (T)));
362 Siz : constant Int := Component_Count (Component_Type (T));
365 if not Compile_Time_Known_Value (Lo)
366 or else not Compile_Time_Known_Value (Hi)
371 Siz * UI_To_Int (Expr_Value (Hi) - Expr_Value (Lo) + 1);
376 -- Can only be a null for an access type
382 -- Start of processing for Aggr_Size_OK
385 Siz := Component_Count (Component_Type (Typ));
387 Indx := First_Index (Typ);
388 while Present (Indx) loop
389 Lo := Type_Low_Bound (Etype (Indx));
390 Hi := Type_High_Bound (Etype (Indx));
392 -- Bounds need to be known at compile time
394 if not Compile_Time_Known_Value (Lo)
395 or else not Compile_Time_Known_Value (Hi)
400 Lov := Expr_Value (Lo);
401 Hiv := Expr_Value (Hi);
403 -- A flat array is always safe
409 -- One-component aggregates are suspicious, and if the context type
410 -- is an object declaration with non-static bounds it will trip gcc;
411 -- such an aggregate must be expanded into a single assignment.
414 and then Nkind (Parent (N)) = N_Object_Declaration
417 Index_Type : constant Entity_Id :=
420 (Etype (Defining_Identifier (Parent (N)))));
424 if not Compile_Time_Known_Value (Type_Low_Bound (Index_Type))
425 or else not Compile_Time_Known_Value
426 (Type_High_Bound (Index_Type))
428 if Present (Component_Associations (N)) then
430 First (Choices (First (Component_Associations (N))));
431 if Is_Entity_Name (Indx)
432 and then not Is_Type (Entity (Indx))
435 ("single component aggregate in non-static context?",
437 Error_Msg_N ("\maybe subtype name was meant?", Indx);
447 Rng : constant Uint := Hiv - Lov + 1;
450 -- Check if size is too large
452 if not UI_Is_In_Int_Range (Rng) then
456 Siz := Siz * UI_To_Int (Rng);
460 or else Siz > Max_Aggr_Size
465 -- Bounds must be in integer range, for later array construction
467 if not UI_Is_In_Int_Range (Lov)
469 not UI_Is_In_Int_Range (Hiv)
480 ---------------------------------
481 -- Backend_Processing_Possible --
482 ---------------------------------
484 -- Backend processing by Gigi/gcc is possible only if all the following
485 -- conditions are met:
487 -- 1. N is fully positional
489 -- 2. N is not a bit-packed array aggregate;
491 -- 3. The size of N's array type must be known at compile time. Note
492 -- that this implies that the component size is also known
494 -- 4. The array type of N does not follow the Fortran layout convention
495 -- or if it does it must be 1 dimensional.
497 -- 5. The array component type may not be tagged (which could necessitate
498 -- reassignment of proper tags).
500 -- 6. The array component type must not have unaligned bit components
502 -- 7. None of the components of the aggregate may be bit unaligned
505 -- 8. There cannot be delayed components, since we do not know enough
506 -- at this stage to know if back end processing is possible.
508 -- 9. There cannot be any discriminated record components, since the
509 -- back end cannot handle this complex case.
511 -- 10. No controlled actions need to be generated for components
513 -- 11. For a VM back end, the array should have no aliased components
515 function Backend_Processing_Possible (N : Node_Id) return Boolean is
516 Typ : constant Entity_Id := Etype (N);
517 -- Typ is the correct constrained array subtype of the aggregate
519 function Component_Check (N : Node_Id; Index : Node_Id) return Boolean;
520 -- This routine checks components of aggregate N, enforcing checks
521 -- 1, 7, 8, and 9. In the multi-dimensional case, these checks are
522 -- performed on subaggregates. The Index value is the current index
523 -- being checked in the multi-dimensional case.
525 ---------------------
526 -- Component_Check --
527 ---------------------
529 function Component_Check (N : Node_Id; Index : Node_Id) return Boolean is
533 -- Checks 1: (no component associations)
535 if Present (Component_Associations (N)) then
539 -- Checks on components
541 -- Recurse to check subaggregates, which may appear in qualified
542 -- expressions. If delayed, the front-end will have to expand.
543 -- If the component is a discriminated record, treat as non-static,
544 -- as the back-end cannot handle this properly.
546 Expr := First (Expressions (N));
547 while Present (Expr) loop
549 -- Checks 8: (no delayed components)
551 if Is_Delayed_Aggregate (Expr) then
555 -- Checks 9: (no discriminated records)
557 if Present (Etype (Expr))
558 and then Is_Record_Type (Etype (Expr))
559 and then Has_Discriminants (Etype (Expr))
564 -- Checks 7. Component must not be bit aligned component
566 if Possible_Bit_Aligned_Component (Expr) then
570 -- Recursion to following indexes for multiple dimension case
572 if Present (Next_Index (Index))
573 and then not Component_Check (Expr, Next_Index (Index))
578 -- All checks for that component finished, on to next
586 -- Start of processing for Backend_Processing_Possible
589 -- Checks 2 (array not bit packed) and 10 (no controlled actions)
591 if Is_Bit_Packed_Array (Typ) or else Needs_Finalization (Typ) then
595 -- If component is limited, aggregate must be expanded because each
596 -- component assignment must be built in place.
598 if Is_Immutably_Limited_Type (Component_Type (Typ)) then
602 -- Checks 4 (array must not be multi-dimensional Fortran case)
604 if Convention (Typ) = Convention_Fortran
605 and then Number_Dimensions (Typ) > 1
610 -- Checks 3 (size of array must be known at compile time)
612 if not Size_Known_At_Compile_Time (Typ) then
616 -- Checks on components
618 if not Component_Check (N, First_Index (Typ)) then
622 -- Checks 5 (if the component type is tagged, then we may need to do
623 -- tag adjustments. Perhaps this should be refined to check for any
624 -- component associations that actually need tag adjustment, similar
625 -- to the test in Component_Not_OK_For_Backend for record aggregates
626 -- with tagged components, but not clear whether it's worthwhile ???;
627 -- in the case of the JVM, object tags are handled implicitly)
629 if Is_Tagged_Type (Component_Type (Typ))
630 and then Tagged_Type_Expansion
635 -- Checks 6 (component type must not have bit aligned components)
637 if Type_May_Have_Bit_Aligned_Components (Component_Type (Typ)) then
641 -- Checks 11: Array aggregates with aliased components are currently
642 -- not well supported by the VM backend; disable temporarily this
643 -- backend processing until it is definitely supported.
645 if VM_Target /= No_VM
646 and then Has_Aliased_Components (Base_Type (Typ))
651 -- Backend processing is possible
653 Set_Size_Known_At_Compile_Time (Etype (N), True);
655 end Backend_Processing_Possible;
657 ---------------------------
658 -- Build_Array_Aggr_Code --
659 ---------------------------
661 -- The code that we generate from a one dimensional aggregate is
663 -- 1. If the sub-aggregate contains discrete choices we
665 -- (a) Sort the discrete choices
667 -- (b) Otherwise for each discrete choice that specifies a range we
668 -- emit a loop. If a range specifies a maximum of three values, or
669 -- we are dealing with an expression we emit a sequence of
670 -- assignments instead of a loop.
672 -- (c) Generate the remaining loops to cover the others choice if any
674 -- 2. If the aggregate contains positional elements we
676 -- (a) translate the positional elements in a series of assignments
678 -- (b) Generate a final loop to cover the others choice if any.
679 -- Note that this final loop has to be a while loop since the case
681 -- L : Integer := Integer'Last;
682 -- H : Integer := Integer'Last;
683 -- A : array (L .. H) := (1, others =>0);
685 -- cannot be handled by a for loop. Thus for the following
687 -- array (L .. H) := (.. positional elements.., others =>E);
689 -- we always generate something like:
691 -- J : Index_Type := Index_Of_Last_Positional_Element;
693 -- J := Index_Base'Succ (J)
697 function Build_Array_Aggr_Code
702 Scalar_Comp : Boolean;
703 Indexes : List_Id := No_List;
704 Flist : Node_Id := Empty) return List_Id
706 Loc : constant Source_Ptr := Sloc (N);
707 Index_Base : constant Entity_Id := Base_Type (Etype (Index));
708 Index_Base_L : constant Node_Id := Type_Low_Bound (Index_Base);
709 Index_Base_H : constant Node_Id := Type_High_Bound (Index_Base);
711 function Add (Val : Int; To : Node_Id) return Node_Id;
712 -- Returns an expression where Val is added to expression To, unless
713 -- To+Val is provably out of To's base type range. To must be an
714 -- already analyzed expression.
716 function Empty_Range (L, H : Node_Id) return Boolean;
717 -- Returns True if the range defined by L .. H is certainly empty
719 function Equal (L, H : Node_Id) return Boolean;
720 -- Returns True if L = H for sure
722 function Index_Base_Name return Node_Id;
723 -- Returns a new reference to the index type name
725 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id;
726 -- Ind must be a side-effect free expression. If the input aggregate
727 -- N to Build_Loop contains no sub-aggregates, then this function
728 -- returns the assignment statement:
730 -- Into (Indexes, Ind) := Expr;
732 -- Otherwise we call Build_Code recursively
734 -- Ada 2005 (AI-287): In case of default initialized component, Expr
735 -- is empty and we generate a call to the corresponding IP subprogram.
737 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id;
738 -- Nodes L and H must be side-effect free expressions.
739 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
740 -- This routine returns the for loop statement
742 -- for J in Index_Base'(L) .. Index_Base'(H) loop
743 -- Into (Indexes, J) := Expr;
746 -- Otherwise we call Build_Code recursively.
747 -- As an optimization if the loop covers 3 or less scalar elements we
748 -- generate a sequence of assignments.
750 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id;
751 -- Nodes L and H must be side-effect free expressions.
752 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
753 -- This routine returns the while loop statement
755 -- J : Index_Base := L;
757 -- J := Index_Base'Succ (J);
758 -- Into (Indexes, J) := Expr;
761 -- Otherwise we call Build_Code recursively
763 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean;
764 function Local_Expr_Value (E : Node_Id) return Uint;
765 -- These two Local routines are used to replace the corresponding ones
766 -- in sem_eval because while processing the bounds of an aggregate with
767 -- discrete choices whose index type is an enumeration, we build static
768 -- expressions not recognized by Compile_Time_Known_Value as such since
769 -- they have not yet been analyzed and resolved. All the expressions in
770 -- question are things like Index_Base_Name'Val (Const) which we can
771 -- easily recognize as being constant.
777 function Add (Val : Int; To : Node_Id) return Node_Id is
782 U_Val : constant Uint := UI_From_Int (Val);
785 -- Note: do not try to optimize the case of Val = 0, because
786 -- we need to build a new node with the proper Sloc value anyway.
788 -- First test if we can do constant folding
790 if Local_Compile_Time_Known_Value (To) then
791 U_To := Local_Expr_Value (To) + Val;
793 -- Determine if our constant is outside the range of the index.
794 -- If so return an Empty node. This empty node will be caught
795 -- by Empty_Range below.
797 if Compile_Time_Known_Value (Index_Base_L)
798 and then U_To < Expr_Value (Index_Base_L)
802 elsif Compile_Time_Known_Value (Index_Base_H)
803 and then U_To > Expr_Value (Index_Base_H)
808 Expr_Pos := Make_Integer_Literal (Loc, U_To);
809 Set_Is_Static_Expression (Expr_Pos);
811 if not Is_Enumeration_Type (Index_Base) then
814 -- If we are dealing with enumeration return
815 -- Index_Base'Val (Expr_Pos)
819 Make_Attribute_Reference
821 Prefix => Index_Base_Name,
822 Attribute_Name => Name_Val,
823 Expressions => New_List (Expr_Pos));
829 -- If we are here no constant folding possible
831 if not Is_Enumeration_Type (Index_Base) then
834 Left_Opnd => Duplicate_Subexpr (To),
835 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
837 -- If we are dealing with enumeration return
838 -- Index_Base'Val (Index_Base'Pos (To) + Val)
842 Make_Attribute_Reference
844 Prefix => Index_Base_Name,
845 Attribute_Name => Name_Pos,
846 Expressions => New_List (Duplicate_Subexpr (To)));
851 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
854 Make_Attribute_Reference
856 Prefix => Index_Base_Name,
857 Attribute_Name => Name_Val,
858 Expressions => New_List (Expr_Pos));
868 function Empty_Range (L, H : Node_Id) return Boolean is
869 Is_Empty : Boolean := False;
874 -- First check if L or H were already detected as overflowing the
875 -- index base range type by function Add above. If this is so Add
876 -- returns the empty node.
878 if No (L) or else No (H) then
885 -- L > H range is empty
891 -- B_L > H range must be empty
897 -- L > B_H range must be empty
901 High := Index_Base_H;
904 if Local_Compile_Time_Known_Value (Low)
905 and then Local_Compile_Time_Known_Value (High)
908 UI_Gt (Local_Expr_Value (Low), Local_Expr_Value (High));
921 function Equal (L, H : Node_Id) return Boolean is
926 elsif Local_Compile_Time_Known_Value (L)
927 and then Local_Compile_Time_Known_Value (H)
929 return UI_Eq (Local_Expr_Value (L), Local_Expr_Value (H));
939 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id is
940 L : constant List_Id := New_List;
944 New_Indexes : List_Id;
945 Indexed_Comp : Node_Id;
947 Comp_Type : Entity_Id := Empty;
949 function Add_Loop_Actions (Lis : List_Id) return List_Id;
950 -- Collect insert_actions generated in the construction of a
951 -- loop, and prepend them to the sequence of assignments to
952 -- complete the eventual body of the loop.
954 ----------------------
955 -- Add_Loop_Actions --
956 ----------------------
958 function Add_Loop_Actions (Lis : List_Id) return List_Id is
962 -- Ada 2005 (AI-287): Do nothing else in case of default
963 -- initialized component.
968 elsif Nkind (Parent (Expr)) = N_Component_Association
969 and then Present (Loop_Actions (Parent (Expr)))
971 Append_List (Lis, Loop_Actions (Parent (Expr)));
972 Res := Loop_Actions (Parent (Expr));
973 Set_Loop_Actions (Parent (Expr), No_List);
979 end Add_Loop_Actions;
981 -- Start of processing for Gen_Assign
985 New_Indexes := New_List;
987 New_Indexes := New_Copy_List_Tree (Indexes);
990 Append_To (New_Indexes, Ind);
992 if Present (Flist) then
993 F := New_Copy_Tree (Flist);
995 elsif Present (Etype (N)) and then Needs_Finalization (Etype (N)) then
996 if Is_Entity_Name (Into)
997 and then Present (Scope (Entity (Into)))
999 F := Find_Final_List (Scope (Entity (Into)));
1001 F := Find_Final_List (Current_Scope);
1007 if Present (Next_Index (Index)) then
1010 Build_Array_Aggr_Code
1013 Index => Next_Index (Index),
1015 Scalar_Comp => Scalar_Comp,
1016 Indexes => New_Indexes,
1020 -- If we get here then we are at a bottom-level (sub-)aggregate
1024 (Make_Indexed_Component (Loc,
1025 Prefix => New_Copy_Tree (Into),
1026 Expressions => New_Indexes));
1028 Set_Assignment_OK (Indexed_Comp);
1030 -- Ada 2005 (AI-287): In case of default initialized component, Expr
1031 -- is not present (and therefore we also initialize Expr_Q to empty).
1035 elsif Nkind (Expr) = N_Qualified_Expression then
1036 Expr_Q := Expression (Expr);
1041 if Present (Etype (N))
1042 and then Etype (N) /= Any_Composite
1044 Comp_Type := Component_Type (Etype (N));
1045 pragma Assert (Comp_Type = Ctype); -- AI-287
1047 elsif Present (Next (First (New_Indexes))) then
1049 -- Ada 2005 (AI-287): Do nothing in case of default initialized
1050 -- component because we have received the component type in
1051 -- the formal parameter Ctype.
1053 -- ??? Some assert pragmas have been added to check if this new
1054 -- formal can be used to replace this code in all cases.
1056 if Present (Expr) then
1058 -- This is a multidimensional array. Recover the component
1059 -- type from the outermost aggregate, because subaggregates
1060 -- do not have an assigned type.
1067 while Present (P) loop
1068 if Nkind (P) = N_Aggregate
1069 and then Present (Etype (P))
1071 Comp_Type := Component_Type (Etype (P));
1079 pragma Assert (Comp_Type = Ctype); -- AI-287
1084 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
1085 -- default initialized components (otherwise Expr_Q is not present).
1088 and then Nkind_In (Expr_Q, N_Aggregate, N_Extension_Aggregate)
1090 -- At this stage the Expression may not have been analyzed yet
1091 -- because the array aggregate code has not been updated to use
1092 -- the Expansion_Delayed flag and avoid analysis altogether to
1093 -- solve the same problem (see Resolve_Aggr_Expr). So let us do
1094 -- the analysis of non-array aggregates now in order to get the
1095 -- value of Expansion_Delayed flag for the inner aggregate ???
1097 if Present (Comp_Type) and then not Is_Array_Type (Comp_Type) then
1098 Analyze_And_Resolve (Expr_Q, Comp_Type);
1101 if Is_Delayed_Aggregate (Expr_Q) then
1103 -- This is either a subaggregate of a multidimensional array,
1104 -- or a component of an array type whose component type is
1105 -- also an array. In the latter case, the expression may have
1106 -- component associations that provide different bounds from
1107 -- those of the component type, and sliding must occur. Instead
1108 -- of decomposing the current aggregate assignment, force the
1109 -- re-analysis of the assignment, so that a temporary will be
1110 -- generated in the usual fashion, and sliding will take place.
1112 if Nkind (Parent (N)) = N_Assignment_Statement
1113 and then Is_Array_Type (Comp_Type)
1114 and then Present (Component_Associations (Expr_Q))
1115 and then Must_Slide (Comp_Type, Etype (Expr_Q))
1117 Set_Expansion_Delayed (Expr_Q, False);
1118 Set_Analyzed (Expr_Q, False);
1124 Expr_Q, Etype (Expr_Q), Indexed_Comp, F));
1129 -- Ada 2005 (AI-287): In case of default initialized component, call
1130 -- the initialization subprogram associated with the component type.
1131 -- If the component type is an access type, add an explicit null
1132 -- assignment, because for the back-end there is an initialization
1133 -- present for the whole aggregate, and no default initialization
1136 -- In addition, if the component type is controlled, we must call
1137 -- its Initialize procedure explicitly, because there is no explicit
1138 -- object creation that will invoke it otherwise.
1141 if Present (Base_Init_Proc (Base_Type (Ctype)))
1142 or else Has_Task (Base_Type (Ctype))
1145 Build_Initialization_Call (Loc,
1146 Id_Ref => Indexed_Comp,
1148 With_Default_Init => True));
1150 elsif Is_Access_Type (Ctype) then
1152 Make_Assignment_Statement (Loc,
1153 Name => Indexed_Comp,
1154 Expression => Make_Null (Loc)));
1157 if Needs_Finalization (Ctype) then
1160 Ref => New_Copy_Tree (Indexed_Comp),
1162 Flist_Ref => Find_Final_List (Current_Scope),
1163 With_Attach => Make_Integer_Literal (Loc, 1)));
1167 -- Now generate the assignment with no associated controlled
1168 -- actions since the target of the assignment may not have been
1169 -- initialized, it is not possible to Finalize it as expected by
1170 -- normal controlled assignment. The rest of the controlled
1171 -- actions are done manually with the proper finalization list
1172 -- coming from the context.
1175 Make_OK_Assignment_Statement (Loc,
1176 Name => Indexed_Comp,
1177 Expression => New_Copy_Tree (Expr));
1179 if Present (Comp_Type) and then Needs_Finalization (Comp_Type) then
1180 Set_No_Ctrl_Actions (A);
1182 -- If this is an aggregate for an array of arrays, each
1183 -- sub-aggregate will be expanded as well, and even with
1184 -- No_Ctrl_Actions the assignments of inner components will
1185 -- require attachment in their assignments to temporaries.
1186 -- These temporaries must be finalized for each subaggregate,
1187 -- to prevent multiple attachments of the same temporary
1188 -- location to same finalization chain (and consequently
1189 -- circular lists). To ensure that finalization takes place
1190 -- for each subaggregate we wrap the assignment in a block.
1192 if Is_Array_Type (Comp_Type)
1193 and then Nkind (Expr) = N_Aggregate
1196 Make_Block_Statement (Loc,
1197 Handled_Statement_Sequence =>
1198 Make_Handled_Sequence_Of_Statements (Loc,
1199 Statements => New_List (A)));
1205 -- Adjust the tag if tagged (because of possible view
1206 -- conversions), unless compiling for a VM where
1207 -- tags are implicit.
1209 if Present (Comp_Type)
1210 and then Is_Tagged_Type (Comp_Type)
1211 and then Tagged_Type_Expansion
1214 Full_Typ : constant Entity_Id := Underlying_Type (Comp_Type);
1218 Make_OK_Assignment_Statement (Loc,
1220 Make_Selected_Component (Loc,
1221 Prefix => New_Copy_Tree (Indexed_Comp),
1224 (First_Tag_Component (Full_Typ), Loc)),
1227 Unchecked_Convert_To (RTE (RE_Tag),
1229 (Node (First_Elmt (Access_Disp_Table (Full_Typ))),
1236 -- Adjust and attach the component to the proper final list, which
1237 -- can be the controller of the outer record object or the final
1238 -- list associated with the scope.
1240 -- If the component is itself an array of controlled types, whose
1241 -- value is given by a sub-aggregate, then the attach calls have
1242 -- been generated when individual subcomponent are assigned, and
1243 -- must not be done again to prevent malformed finalization chains
1244 -- (see comments above, concerning the creation of a block to hold
1245 -- inner finalization actions).
1247 if Present (Comp_Type)
1248 and then Needs_Finalization (Comp_Type)
1249 and then not Is_Limited_Type (Comp_Type)
1251 (Is_Array_Type (Comp_Type)
1252 and then Is_Controlled (Component_Type (Comp_Type))
1253 and then Nkind (Expr) = N_Aggregate)
1257 Ref => New_Copy_Tree (Indexed_Comp),
1260 With_Attach => Make_Integer_Literal (Loc, 1)));
1264 return Add_Loop_Actions (L);
1271 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id is
1281 -- Index_Base'(L) .. Index_Base'(H)
1283 L_Iteration_Scheme : Node_Id;
1284 -- L_J in Index_Base'(L) .. Index_Base'(H)
1287 -- The statements to execute in the loop
1289 S : constant List_Id := New_List;
1290 -- List of statements
1293 -- Copy of expression tree, used for checking purposes
1296 -- If loop bounds define an empty range return the null statement
1298 if Empty_Range (L, H) then
1299 Append_To (S, Make_Null_Statement (Loc));
1301 -- Ada 2005 (AI-287): Nothing else need to be done in case of
1302 -- default initialized component.
1308 -- The expression must be type-checked even though no component
1309 -- of the aggregate will have this value. This is done only for
1310 -- actual components of the array, not for subaggregates. Do
1311 -- the check on a copy, because the expression may be shared
1312 -- among several choices, some of which might be non-null.
1314 if Present (Etype (N))
1315 and then Is_Array_Type (Etype (N))
1316 and then No (Next_Index (Index))
1318 Expander_Mode_Save_And_Set (False);
1319 Tcopy := New_Copy_Tree (Expr);
1320 Set_Parent (Tcopy, N);
1321 Analyze_And_Resolve (Tcopy, Component_Type (Etype (N)));
1322 Expander_Mode_Restore;
1328 -- If loop bounds are the same then generate an assignment
1330 elsif Equal (L, H) then
1331 return Gen_Assign (New_Copy_Tree (L), Expr);
1333 -- If H - L <= 2 then generate a sequence of assignments when we are
1334 -- processing the bottom most aggregate and it contains scalar
1337 elsif No (Next_Index (Index))
1338 and then Scalar_Comp
1339 and then Local_Compile_Time_Known_Value (L)
1340 and then Local_Compile_Time_Known_Value (H)
1341 and then Local_Expr_Value (H) - Local_Expr_Value (L) <= 2
1344 Append_List_To (S, Gen_Assign (New_Copy_Tree (L), Expr));
1345 Append_List_To (S, Gen_Assign (Add (1, To => L), Expr));
1347 if Local_Expr_Value (H) - Local_Expr_Value (L) = 2 then
1348 Append_List_To (S, Gen_Assign (Add (2, To => L), Expr));
1354 -- Otherwise construct the loop, starting with the loop index L_J
1356 L_J := Make_Temporary (Loc, 'J', L);
1358 -- Construct "L .. H" in Index_Base. We use a qualified expression
1359 -- for the bound to convert to the index base, but we don't need
1360 -- to do that if we already have the base type at hand.
1362 if Etype (L) = Index_Base then
1366 Make_Qualified_Expression (Loc,
1367 Subtype_Mark => Index_Base_Name,
1371 if Etype (H) = Index_Base then
1375 Make_Qualified_Expression (Loc,
1376 Subtype_Mark => Index_Base_Name,
1385 -- Construct "for L_J in Index_Base range L .. H"
1387 L_Iteration_Scheme :=
1388 Make_Iteration_Scheme
1390 Loop_Parameter_Specification =>
1391 Make_Loop_Parameter_Specification
1393 Defining_Identifier => L_J,
1394 Discrete_Subtype_Definition => L_Range));
1396 -- Construct the statements to execute in the loop body
1398 L_Body := Gen_Assign (New_Reference_To (L_J, Loc), Expr);
1400 -- Construct the final loop
1402 Append_To (S, Make_Implicit_Loop_Statement
1404 Identifier => Empty,
1405 Iteration_Scheme => L_Iteration_Scheme,
1406 Statements => L_Body));
1408 -- A small optimization: if the aggregate is initialized with a box
1409 -- and the component type has no initialization procedure, remove the
1410 -- useless empty loop.
1412 if Nkind (First (S)) = N_Loop_Statement
1413 and then Is_Empty_List (Statements (First (S)))
1415 return New_List (Make_Null_Statement (Loc));
1425 -- The code built is
1427 -- W_J : Index_Base := L;
1428 -- while W_J < H loop
1429 -- W_J := Index_Base'Succ (W);
1433 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id is
1437 -- W_J : Base_Type := L;
1439 W_Iteration_Scheme : Node_Id;
1442 W_Index_Succ : Node_Id;
1443 -- Index_Base'Succ (J)
1445 W_Increment : Node_Id;
1446 -- W_J := Index_Base'Succ (W)
1448 W_Body : constant List_Id := New_List;
1449 -- The statements to execute in the loop
1451 S : constant List_Id := New_List;
1452 -- list of statement
1455 -- If loop bounds define an empty range or are equal return null
1457 if Empty_Range (L, H) or else Equal (L, H) then
1458 Append_To (S, Make_Null_Statement (Loc));
1462 -- Build the decl of W_J
1464 W_J := Make_Temporary (Loc, 'J', L);
1466 Make_Object_Declaration
1468 Defining_Identifier => W_J,
1469 Object_Definition => Index_Base_Name,
1472 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1473 -- that in this particular case L is a fresh Expr generated by
1474 -- Add which we are the only ones to use.
1476 Append_To (S, W_Decl);
1478 -- Construct " while W_J < H"
1480 W_Iteration_Scheme :=
1481 Make_Iteration_Scheme
1483 Condition => Make_Op_Lt
1485 Left_Opnd => New_Reference_To (W_J, Loc),
1486 Right_Opnd => New_Copy_Tree (H)));
1488 -- Construct the statements to execute in the loop body
1491 Make_Attribute_Reference
1493 Prefix => Index_Base_Name,
1494 Attribute_Name => Name_Succ,
1495 Expressions => New_List (New_Reference_To (W_J, Loc)));
1498 Make_OK_Assignment_Statement
1500 Name => New_Reference_To (W_J, Loc),
1501 Expression => W_Index_Succ);
1503 Append_To (W_Body, W_Increment);
1504 Append_List_To (W_Body,
1505 Gen_Assign (New_Reference_To (W_J, Loc), Expr));
1507 -- Construct the final loop
1509 Append_To (S, Make_Implicit_Loop_Statement
1511 Identifier => Empty,
1512 Iteration_Scheme => W_Iteration_Scheme,
1513 Statements => W_Body));
1518 ---------------------
1519 -- Index_Base_Name --
1520 ---------------------
1522 function Index_Base_Name return Node_Id is
1524 return New_Reference_To (Index_Base, Sloc (N));
1525 end Index_Base_Name;
1527 ------------------------------------
1528 -- Local_Compile_Time_Known_Value --
1529 ------------------------------------
1531 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean is
1533 return Compile_Time_Known_Value (E)
1535 (Nkind (E) = N_Attribute_Reference
1536 and then Attribute_Name (E) = Name_Val
1537 and then Compile_Time_Known_Value (First (Expressions (E))));
1538 end Local_Compile_Time_Known_Value;
1540 ----------------------
1541 -- Local_Expr_Value --
1542 ----------------------
1544 function Local_Expr_Value (E : Node_Id) return Uint is
1546 if Compile_Time_Known_Value (E) then
1547 return Expr_Value (E);
1549 return Expr_Value (First (Expressions (E)));
1551 end Local_Expr_Value;
1553 -- Build_Array_Aggr_Code Variables
1560 Others_Expr : Node_Id := Empty;
1561 Others_Box_Present : Boolean := False;
1563 Aggr_L : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
1564 Aggr_H : constant Node_Id := High_Bound (Aggregate_Bounds (N));
1565 -- The aggregate bounds of this specific sub-aggregate. Note that if
1566 -- the code generated by Build_Array_Aggr_Code is executed then these
1567 -- bounds are OK. Otherwise a Constraint_Error would have been raised.
1569 Aggr_Low : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_L);
1570 Aggr_High : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_H);
1571 -- After Duplicate_Subexpr these are side-effect free
1576 Nb_Choices : Nat := 0;
1577 Table : Case_Table_Type (1 .. Number_Of_Choices (N));
1578 -- Used to sort all the different choice values
1581 -- Number of elements in the positional aggregate
1583 New_Code : constant List_Id := New_List;
1585 -- Start of processing for Build_Array_Aggr_Code
1588 -- First before we start, a special case. if we have a bit packed
1589 -- array represented as a modular type, then clear the value to
1590 -- zero first, to ensure that unused bits are properly cleared.
1595 and then Is_Bit_Packed_Array (Typ)
1596 and then Is_Modular_Integer_Type (Packed_Array_Type (Typ))
1598 Append_To (New_Code,
1599 Make_Assignment_Statement (Loc,
1600 Name => New_Copy_Tree (Into),
1602 Unchecked_Convert_To (Typ,
1603 Make_Integer_Literal (Loc, Uint_0))));
1606 -- If the component type contains tasks, we need to build a Master
1607 -- entity in the current scope, because it will be needed if build-
1608 -- in-place functions are called in the expanded code.
1610 if Nkind (Parent (N)) = N_Object_Declaration
1611 and then Has_Task (Typ)
1613 Build_Master_Entity (Defining_Identifier (Parent (N)));
1616 -- STEP 1: Process component associations
1618 -- For those associations that may generate a loop, initialize
1619 -- Loop_Actions to collect inserted actions that may be crated.
1621 -- Skip this if no component associations
1623 if No (Expressions (N)) then
1625 -- STEP 1 (a): Sort the discrete choices
1627 Assoc := First (Component_Associations (N));
1628 while Present (Assoc) loop
1629 Choice := First (Choices (Assoc));
1630 while Present (Choice) loop
1631 if Nkind (Choice) = N_Others_Choice then
1632 Set_Loop_Actions (Assoc, New_List);
1634 if Box_Present (Assoc) then
1635 Others_Box_Present := True;
1637 Others_Expr := Expression (Assoc);
1642 Get_Index_Bounds (Choice, Low, High);
1645 Set_Loop_Actions (Assoc, New_List);
1648 Nb_Choices := Nb_Choices + 1;
1649 if Box_Present (Assoc) then
1650 Table (Nb_Choices) := (Choice_Lo => Low,
1652 Choice_Node => Empty);
1654 Table (Nb_Choices) := (Choice_Lo => Low,
1656 Choice_Node => Expression (Assoc));
1664 -- If there is more than one set of choices these must be static
1665 -- and we can therefore sort them. Remember that Nb_Choices does not
1666 -- account for an others choice.
1668 if Nb_Choices > 1 then
1669 Sort_Case_Table (Table);
1672 -- STEP 1 (b): take care of the whole set of discrete choices
1674 for J in 1 .. Nb_Choices loop
1675 Low := Table (J).Choice_Lo;
1676 High := Table (J).Choice_Hi;
1677 Expr := Table (J).Choice_Node;
1678 Append_List (Gen_Loop (Low, High, Expr), To => New_Code);
1681 -- STEP 1 (c): generate the remaining loops to cover others choice
1682 -- We don't need to generate loops over empty gaps, but if there is
1683 -- a single empty range we must analyze the expression for semantics
1685 if Present (Others_Expr) or else Others_Box_Present then
1687 First : Boolean := True;
1690 for J in 0 .. Nb_Choices loop
1694 Low := Add (1, To => Table (J).Choice_Hi);
1697 if J = Nb_Choices then
1700 High := Add (-1, To => Table (J + 1).Choice_Lo);
1703 -- If this is an expansion within an init proc, make
1704 -- sure that discriminant references are replaced by
1705 -- the corresponding discriminal.
1707 if Inside_Init_Proc then
1708 if Is_Entity_Name (Low)
1709 and then Ekind (Entity (Low)) = E_Discriminant
1711 Set_Entity (Low, Discriminal (Entity (Low)));
1714 if Is_Entity_Name (High)
1715 and then Ekind (Entity (High)) = E_Discriminant
1717 Set_Entity (High, Discriminal (Entity (High)));
1722 or else not Empty_Range (Low, High)
1726 (Gen_Loop (Low, High, Others_Expr), To => New_Code);
1732 -- STEP 2: Process positional components
1735 -- STEP 2 (a): Generate the assignments for each positional element
1736 -- Note that here we have to use Aggr_L rather than Aggr_Low because
1737 -- Aggr_L is analyzed and Add wants an analyzed expression.
1739 Expr := First (Expressions (N));
1741 while Present (Expr) loop
1742 Nb_Elements := Nb_Elements + 1;
1743 Append_List (Gen_Assign (Add (Nb_Elements, To => Aggr_L), Expr),
1748 -- STEP 2 (b): Generate final loop if an others choice is present
1749 -- Here Nb_Elements gives the offset of the last positional element.
1751 if Present (Component_Associations (N)) then
1752 Assoc := Last (Component_Associations (N));
1754 -- Ada 2005 (AI-287)
1756 if Box_Present (Assoc) then
1757 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1762 Expr := Expression (Assoc);
1764 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1773 end Build_Array_Aggr_Code;
1775 ----------------------------
1776 -- Build_Record_Aggr_Code --
1777 ----------------------------
1779 function Build_Record_Aggr_Code
1783 Flist : Node_Id := Empty;
1784 Obj : Entity_Id := Empty;
1785 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id
1787 Loc : constant Source_Ptr := Sloc (N);
1788 L : constant List_Id := New_List;
1789 N_Typ : constant Entity_Id := Etype (N);
1796 Comp_Type : Entity_Id;
1797 Selector : Entity_Id;
1798 Comp_Expr : Node_Id;
1801 Internal_Final_List : Node_Id := Empty;
1803 -- If this is an internal aggregate, the External_Final_List is an
1804 -- expression for the controller record of the enclosing type.
1806 -- If the current aggregate has several controlled components, this
1807 -- expression will appear in several calls to attach to the finali-
1808 -- zation list, and it must not be shared.
1810 External_Final_List : Node_Id;
1811 Ancestor_Is_Expression : Boolean := False;
1812 Ancestor_Is_Subtype_Mark : Boolean := False;
1814 Init_Typ : Entity_Id := Empty;
1817 Ctrl_Stuff_Done : Boolean := False;
1818 -- True if Gen_Ctrl_Actions_For_Aggr has already been called; calls
1819 -- after the first do nothing.
1821 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id;
1822 -- Returns the value that the given discriminant of an ancestor type
1823 -- should receive (in the absence of a conflict with the value provided
1824 -- by an ancestor part of an extension aggregate).
1826 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id);
1827 -- Check that each of the discriminant values defined by the ancestor
1828 -- part of an extension aggregate match the corresponding values
1829 -- provided by either an association of the aggregate or by the
1830 -- constraint imposed by a parent type (RM95-4.3.2(8)).
1832 function Compatible_Int_Bounds
1833 (Agg_Bounds : Node_Id;
1834 Typ_Bounds : Node_Id) return Boolean;
1835 -- Return true if Agg_Bounds are equal or within Typ_Bounds. It is
1836 -- assumed that both bounds are integer ranges.
1838 procedure Gen_Ctrl_Actions_For_Aggr;
1839 -- Deal with the various controlled type data structure initializations
1840 -- (but only if it hasn't been done already).
1842 function Get_Constraint_Association (T : Entity_Id) return Node_Id;
1843 -- Returns the first discriminant association in the constraint
1844 -- associated with T, if any, otherwise returns Empty.
1846 function Init_Controller
1851 Init_Pr : Boolean) return List_Id;
1852 -- Returns the list of statements necessary to initialize the internal
1853 -- controller of the (possible) ancestor typ into target and attach it
1854 -- to finalization list F. Init_Pr conditions the call to the init proc
1855 -- since it may already be done due to ancestor initialization.
1857 procedure Init_Hidden_Discriminants (Typ : Entity_Id; List : List_Id);
1858 -- If Typ is derived, and constrains discriminants of the parent type,
1859 -- these discriminants are not components of the aggregate, and must be
1860 -- initialized. The assignments are appended to List.
1862 function Is_Int_Range_Bounds (Bounds : Node_Id) return Boolean;
1863 -- Check whether Bounds is a range node and its lower and higher bounds
1864 -- are integers literals.
1866 ---------------------------------
1867 -- Ancestor_Discriminant_Value --
1868 ---------------------------------
1870 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id is
1872 Assoc_Elmt : Elmt_Id;
1873 Aggr_Comp : Entity_Id;
1874 Corresp_Disc : Entity_Id;
1875 Current_Typ : Entity_Id := Base_Type (Typ);
1876 Parent_Typ : Entity_Id;
1877 Parent_Disc : Entity_Id;
1878 Save_Assoc : Node_Id := Empty;
1881 -- First check any discriminant associations to see if any of them
1882 -- provide a value for the discriminant.
1884 if Present (Discriminant_Specifications (Parent (Current_Typ))) then
1885 Assoc := First (Component_Associations (N));
1886 while Present (Assoc) loop
1887 Aggr_Comp := Entity (First (Choices (Assoc)));
1889 if Ekind (Aggr_Comp) = E_Discriminant then
1890 Save_Assoc := Expression (Assoc);
1892 Corresp_Disc := Corresponding_Discriminant (Aggr_Comp);
1893 while Present (Corresp_Disc) loop
1895 -- If found a corresponding discriminant then return the
1896 -- value given in the aggregate. (Note: this is not
1897 -- correct in the presence of side effects. ???)
1899 if Disc = Corresp_Disc then
1900 return Duplicate_Subexpr (Expression (Assoc));
1904 Corresponding_Discriminant (Corresp_Disc);
1912 -- No match found in aggregate, so chain up parent types to find
1913 -- a constraint that defines the value of the discriminant.
1915 Parent_Typ := Etype (Current_Typ);
1916 while Current_Typ /= Parent_Typ loop
1917 if Has_Discriminants (Parent_Typ)
1918 and then not Has_Unknown_Discriminants (Parent_Typ)
1920 Parent_Disc := First_Discriminant (Parent_Typ);
1922 -- We either get the association from the subtype indication
1923 -- of the type definition itself, or from the discriminant
1924 -- constraint associated with the type entity (which is
1925 -- preferable, but it's not always present ???)
1927 if Is_Empty_Elmt_List (
1928 Discriminant_Constraint (Current_Typ))
1930 Assoc := Get_Constraint_Association (Current_Typ);
1931 Assoc_Elmt := No_Elmt;
1934 First_Elmt (Discriminant_Constraint (Current_Typ));
1935 Assoc := Node (Assoc_Elmt);
1938 -- Traverse the discriminants of the parent type looking
1939 -- for one that corresponds.
1941 while Present (Parent_Disc) and then Present (Assoc) loop
1942 Corresp_Disc := Parent_Disc;
1943 while Present (Corresp_Disc)
1944 and then Disc /= Corresp_Disc
1947 Corresponding_Discriminant (Corresp_Disc);
1950 if Disc = Corresp_Disc then
1951 if Nkind (Assoc) = N_Discriminant_Association then
1952 Assoc := Expression (Assoc);
1955 -- If the located association directly denotes a
1956 -- discriminant, then use the value of a saved
1957 -- association of the aggregate. This is a kludge to
1958 -- handle certain cases involving multiple discriminants
1959 -- mapped to a single discriminant of a descendant. It's
1960 -- not clear how to locate the appropriate discriminant
1961 -- value for such cases. ???
1963 if Is_Entity_Name (Assoc)
1964 and then Ekind (Entity (Assoc)) = E_Discriminant
1966 Assoc := Save_Assoc;
1969 return Duplicate_Subexpr (Assoc);
1972 Next_Discriminant (Parent_Disc);
1974 if No (Assoc_Elmt) then
1977 Next_Elmt (Assoc_Elmt);
1978 if Present (Assoc_Elmt) then
1979 Assoc := Node (Assoc_Elmt);
1987 Current_Typ := Parent_Typ;
1988 Parent_Typ := Etype (Current_Typ);
1991 -- In some cases there's no ancestor value to locate (such as
1992 -- when an ancestor part given by an expression defines the
1993 -- discriminant value).
1996 end Ancestor_Discriminant_Value;
1998 ----------------------------------
1999 -- Check_Ancestor_Discriminants --
2000 ----------------------------------
2002 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id) is
2004 Disc_Value : Node_Id;
2008 Discr := First_Discriminant (Base_Type (Anc_Typ));
2009 while Present (Discr) loop
2010 Disc_Value := Ancestor_Discriminant_Value (Discr);
2012 if Present (Disc_Value) then
2013 Cond := Make_Op_Ne (Loc,
2015 Make_Selected_Component (Loc,
2016 Prefix => New_Copy_Tree (Target),
2017 Selector_Name => New_Occurrence_Of (Discr, Loc)),
2018 Right_Opnd => Disc_Value);
2021 Make_Raise_Constraint_Error (Loc,
2023 Reason => CE_Discriminant_Check_Failed));
2026 Next_Discriminant (Discr);
2028 end Check_Ancestor_Discriminants;
2030 ---------------------------
2031 -- Compatible_Int_Bounds --
2032 ---------------------------
2034 function Compatible_Int_Bounds
2035 (Agg_Bounds : Node_Id;
2036 Typ_Bounds : Node_Id) return Boolean
2038 Agg_Lo : constant Uint := Intval (Low_Bound (Agg_Bounds));
2039 Agg_Hi : constant Uint := Intval (High_Bound (Agg_Bounds));
2040 Typ_Lo : constant Uint := Intval (Low_Bound (Typ_Bounds));
2041 Typ_Hi : constant Uint := Intval (High_Bound (Typ_Bounds));
2043 return Typ_Lo <= Agg_Lo and then Agg_Hi <= Typ_Hi;
2044 end Compatible_Int_Bounds;
2046 --------------------------------
2047 -- Get_Constraint_Association --
2048 --------------------------------
2050 function Get_Constraint_Association (T : Entity_Id) return Node_Id is
2051 Typ_Def : constant Node_Id := Type_Definition (Parent (T));
2052 Indic : constant Node_Id := Subtype_Indication (Typ_Def);
2055 -- ??? Also need to cover case of a type mark denoting a subtype
2058 if Nkind (Indic) = N_Subtype_Indication
2059 and then Present (Constraint (Indic))
2061 return First (Constraints (Constraint (Indic)));
2065 end Get_Constraint_Association;
2067 ---------------------
2068 -- Init_Controller --
2069 ---------------------
2071 function Init_Controller
2076 Init_Pr : Boolean) return List_Id
2078 L : constant List_Id := New_List;
2081 Target_Type : Entity_Id;
2085 -- init-proc (target._controller);
2086 -- initialize (target._controller);
2087 -- Attach_to_Final_List (target._controller, F);
2090 Make_Selected_Component (Loc,
2091 Prefix => Convert_To (Typ, New_Copy_Tree (Target)),
2092 Selector_Name => Make_Identifier (Loc, Name_uController));
2093 Set_Assignment_OK (Ref);
2095 -- Ada 2005 (AI-287): Give support to aggregates of limited types.
2096 -- If the type is intrinsically limited the controller is limited as
2097 -- well. If it is tagged and limited then so is the controller.
2098 -- Otherwise an untagged type may have limited components without its
2099 -- full view being limited, so the controller is not limited.
2101 if Nkind (Target) = N_Identifier then
2102 Target_Type := Etype (Target);
2104 elsif Nkind (Target) = N_Selected_Component then
2105 Target_Type := Etype (Selector_Name (Target));
2107 elsif Nkind (Target) = N_Unchecked_Type_Conversion then
2108 Target_Type := Etype (Target);
2110 elsif Nkind (Target) = N_Unchecked_Expression
2111 and then Nkind (Expression (Target)) = N_Indexed_Component
2113 Target_Type := Etype (Prefix (Expression (Target)));
2116 Target_Type := Etype (Target);
2119 -- If the target has not been analyzed yet, as will happen with
2120 -- delayed expansion, use the given type (either the aggregate type
2121 -- or an ancestor) to determine limitedness.
2123 if No (Target_Type) then
2127 if (Is_Tagged_Type (Target_Type))
2128 and then Is_Limited_Type (Target_Type)
2130 RC := RE_Limited_Record_Controller;
2132 elsif Is_Immutably_Limited_Type (Target_Type) then
2133 RC := RE_Limited_Record_Controller;
2136 RC := RE_Record_Controller;
2141 Build_Initialization_Call (Loc,
2144 In_Init_Proc => Within_Init_Proc));
2148 Make_Procedure_Call_Statement (Loc,
2151 Find_Prim_Op (RTE (RC), Name_Initialize), Loc),
2152 Parameter_Associations =>
2153 New_List (New_Copy_Tree (Ref))));
2157 Obj_Ref => New_Copy_Tree (Ref),
2159 With_Attach => Attach));
2162 end Init_Controller;
2164 -------------------------------
2165 -- Init_Hidden_Discriminants --
2166 -------------------------------
2168 procedure Init_Hidden_Discriminants (Typ : Entity_Id; List : List_Id) is
2170 Parent_Type : Entity_Id;
2172 Discr_Val : Elmt_Id;
2175 Btype := Base_Type (Typ);
2176 while Is_Derived_Type (Btype)
2177 and then Present (Stored_Constraint (Btype))
2179 Parent_Type := Etype (Btype);
2181 Disc := First_Discriminant (Parent_Type);
2182 Discr_Val := First_Elmt (Stored_Constraint (Base_Type (Typ)));
2183 while Present (Discr_Val) loop
2185 -- Only those discriminants of the parent that are not
2186 -- renamed by discriminants of the derived type need to
2187 -- be added explicitly.
2189 if not Is_Entity_Name (Node (Discr_Val))
2190 or else Ekind (Entity (Node (Discr_Val))) /= E_Discriminant
2193 Make_Selected_Component (Loc,
2194 Prefix => New_Copy_Tree (Target),
2195 Selector_Name => New_Occurrence_Of (Disc, Loc));
2198 Make_OK_Assignment_Statement (Loc,
2200 Expression => New_Copy_Tree (Node (Discr_Val)));
2202 Set_No_Ctrl_Actions (Instr);
2203 Append_To (List, Instr);
2206 Next_Discriminant (Disc);
2207 Next_Elmt (Discr_Val);
2210 Btype := Base_Type (Parent_Type);
2212 end Init_Hidden_Discriminants;
2214 -------------------------
2215 -- Is_Int_Range_Bounds --
2216 -------------------------
2218 function Is_Int_Range_Bounds (Bounds : Node_Id) return Boolean is
2220 return Nkind (Bounds) = N_Range
2221 and then Nkind (Low_Bound (Bounds)) = N_Integer_Literal
2222 and then Nkind (High_Bound (Bounds)) = N_Integer_Literal;
2223 end Is_Int_Range_Bounds;
2225 -------------------------------
2226 -- Gen_Ctrl_Actions_For_Aggr --
2227 -------------------------------
2229 procedure Gen_Ctrl_Actions_For_Aggr is
2230 Alloc : Node_Id := Empty;
2233 -- Do the work only the first time this is called
2235 if Ctrl_Stuff_Done then
2239 Ctrl_Stuff_Done := True;
2242 and then Finalize_Storage_Only (Typ)
2244 (Is_Library_Level_Entity (Obj)
2245 or else Entity (Constant_Value (RTE (RE_Garbage_Collected))) =
2248 -- why not Is_True (Expr_Value (RTE (RE_Garbaage_Collected) ???
2250 Attach := Make_Integer_Literal (Loc, 0);
2252 elsif Nkind (Parent (N)) = N_Qualified_Expression
2253 and then Nkind (Parent (Parent (N))) = N_Allocator
2255 Alloc := Parent (Parent (N));
2256 Attach := Make_Integer_Literal (Loc, 2);
2259 Attach := Make_Integer_Literal (Loc, 1);
2262 -- Determine the external finalization list. It is either the
2263 -- finalization list of the outer-scope or the one coming from
2264 -- an outer aggregate. When the target is not a temporary, the
2265 -- proper scope is the scope of the target rather than the
2266 -- potentially transient current scope.
2268 if Needs_Finalization (Typ) then
2270 -- The current aggregate belongs to an allocator which creates
2271 -- an object through an anonymous access type or acts as the root
2272 -- of a coextension chain.
2276 (Is_Coextension_Root (Alloc)
2277 or else Ekind (Etype (Alloc)) = E_Anonymous_Access_Type)
2279 if No (Associated_Final_Chain (Etype (Alloc))) then
2280 Build_Final_List (Alloc, Etype (Alloc));
2283 External_Final_List :=
2284 Make_Selected_Component (Loc,
2287 Associated_Final_Chain (Etype (Alloc)), Loc),
2288 Selector_Name => Make_Identifier (Loc, Name_F));
2290 elsif Present (Flist) then
2291 External_Final_List := New_Copy_Tree (Flist);
2293 elsif Is_Entity_Name (Target)
2294 and then Present (Scope (Entity (Target)))
2296 External_Final_List :=
2297 Find_Final_List (Scope (Entity (Target)));
2300 External_Final_List := Find_Final_List (Current_Scope);
2303 External_Final_List := Empty;
2306 -- Initialize and attach the outer object in the is_controlled case
2308 if Is_Controlled (Typ) then
2309 if Ancestor_Is_Subtype_Mark then
2310 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2311 Set_Assignment_OK (Ref);
2313 Make_Procedure_Call_Statement (Loc,
2316 (Find_Prim_Op (Init_Typ, Name_Initialize), Loc),
2317 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
2320 if not Has_Controlled_Component (Typ) then
2321 Ref := New_Copy_Tree (Target);
2322 Set_Assignment_OK (Ref);
2324 -- This is an aggregate of a coextension. Do not produce a
2325 -- finalization call, but rather attach the reference of the
2326 -- aggregate to its coextension chain.
2329 and then Is_Dynamic_Coextension (Alloc)
2331 if No (Coextensions (Alloc)) then
2332 Set_Coextensions (Alloc, New_Elmt_List);
2335 Append_Elmt (Ref, Coextensions (Alloc));
2340 Flist_Ref => New_Copy_Tree (External_Final_List),
2341 With_Attach => Attach));
2346 -- In the Has_Controlled component case, all the intermediate
2347 -- controllers must be initialized.
2349 if Has_Controlled_Component (Typ)
2350 and not Is_Limited_Ancestor_Expansion
2353 Inner_Typ : Entity_Id;
2354 Outer_Typ : Entity_Id;
2358 -- Find outer type with a controller
2360 Outer_Typ := Base_Type (Typ);
2361 while Outer_Typ /= Init_Typ
2362 and then not Has_New_Controlled_Component (Outer_Typ)
2364 Outer_Typ := Etype (Outer_Typ);
2367 -- Attach it to the outer record controller to the external
2370 if Outer_Typ = Init_Typ then
2375 F => External_Final_List,
2380 Inner_Typ := Init_Typ;
2387 F => External_Final_List,
2391 Inner_Typ := Etype (Outer_Typ);
2393 not Is_Tagged_Type (Typ) or else Inner_Typ = Outer_Typ;
2396 -- The outer object has to be attached as well
2398 if Is_Controlled (Typ) then
2399 Ref := New_Copy_Tree (Target);
2400 Set_Assignment_OK (Ref);
2404 Flist_Ref => New_Copy_Tree (External_Final_List),
2405 With_Attach => New_Copy_Tree (Attach)));
2408 -- Initialize the internal controllers for tagged types with
2409 -- more than one controller.
2411 while not At_Root and then Inner_Typ /= Init_Typ loop
2412 if Has_New_Controlled_Component (Inner_Typ) then
2414 Make_Selected_Component (Loc,
2416 Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2418 Make_Identifier (Loc, Name_uController));
2420 Make_Selected_Component (Loc,
2422 Selector_Name => Make_Identifier (Loc, Name_F));
2429 Attach => Make_Integer_Literal (Loc, 1),
2431 Outer_Typ := Inner_Typ;
2436 At_Root := Inner_Typ = Etype (Inner_Typ);
2437 Inner_Typ := Etype (Inner_Typ);
2440 -- If not done yet attach the controller of the ancestor part
2442 if Outer_Typ /= Init_Typ
2443 and then Inner_Typ = Init_Typ
2444 and then Has_Controlled_Component (Init_Typ)
2447 Make_Selected_Component (Loc,
2448 Prefix => Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2450 Make_Identifier (Loc, Name_uController));
2452 Make_Selected_Component (Loc,
2454 Selector_Name => Make_Identifier (Loc, Name_F));
2456 Attach := Make_Integer_Literal (Loc, 1);
2465 -- Note: Init_Pr is False because the ancestor part has
2466 -- already been initialized either way (by default, if
2467 -- given by a type name, otherwise from the expression).
2472 end Gen_Ctrl_Actions_For_Aggr;
2474 function Rewrite_Discriminant (Expr : Node_Id) return Traverse_Result;
2475 -- If default expression of a component mentions a discriminant of the
2476 -- type, it must be rewritten as the discriminant of the target object.
2478 function Replace_Type (Expr : Node_Id) return Traverse_Result;
2479 -- If the aggregate contains a self-reference, traverse each expression
2480 -- to replace a possible self-reference with a reference to the proper
2481 -- component of the target of the assignment.
2483 --------------------------
2484 -- Rewrite_Discriminant --
2485 --------------------------
2487 function Rewrite_Discriminant (Expr : Node_Id) return Traverse_Result is
2489 if Is_Entity_Name (Expr)
2490 and then Present (Entity (Expr))
2491 and then Ekind (Entity (Expr)) = E_In_Parameter
2492 and then Present (Discriminal_Link (Entity (Expr)))
2493 and then Scope (Discriminal_Link (Entity (Expr)))
2494 = Base_Type (Etype (N))
2497 Make_Selected_Component (Loc,
2498 Prefix => New_Copy_Tree (Lhs),
2499 Selector_Name => Make_Identifier (Loc, Chars (Expr))));
2502 end Rewrite_Discriminant;
2508 function Replace_Type (Expr : Node_Id) return Traverse_Result is
2510 -- Note regarding the Root_Type test below: Aggregate components for
2511 -- self-referential types include attribute references to the current
2512 -- instance, of the form: Typ'access, etc.. These references are
2513 -- rewritten as references to the target of the aggregate: the
2514 -- left-hand side of an assignment, the entity in a declaration,
2515 -- or a temporary. Without this test, we would improperly extended
2516 -- this rewriting to attribute references whose prefix was not the
2517 -- type of the aggregate.
2519 if Nkind (Expr) = N_Attribute_Reference
2520 and then Is_Entity_Name (Prefix (Expr))
2521 and then Is_Type (Entity (Prefix (Expr)))
2522 and then Root_Type (Etype (N)) = Root_Type (Entity (Prefix (Expr)))
2524 if Is_Entity_Name (Lhs) then
2525 Rewrite (Prefix (Expr),
2526 New_Occurrence_Of (Entity (Lhs), Loc));
2528 elsif Nkind (Lhs) = N_Selected_Component then
2530 Make_Attribute_Reference (Loc,
2531 Attribute_Name => Name_Unrestricted_Access,
2532 Prefix => New_Copy_Tree (Prefix (Lhs))));
2533 Set_Analyzed (Parent (Expr), False);
2537 Make_Attribute_Reference (Loc,
2538 Attribute_Name => Name_Unrestricted_Access,
2539 Prefix => New_Copy_Tree (Lhs)));
2540 Set_Analyzed (Parent (Expr), False);
2547 procedure Replace_Self_Reference is
2548 new Traverse_Proc (Replace_Type);
2550 procedure Replace_Discriminants is
2551 new Traverse_Proc (Rewrite_Discriminant);
2553 -- Start of processing for Build_Record_Aggr_Code
2556 if Has_Self_Reference (N) then
2557 Replace_Self_Reference (N);
2560 -- If the target of the aggregate is class-wide, we must convert it
2561 -- to the actual type of the aggregate, so that the proper components
2562 -- are visible. We know already that the types are compatible.
2564 if Present (Etype (Lhs))
2565 and then Is_Class_Wide_Type (Etype (Lhs))
2567 Target := Unchecked_Convert_To (Typ, Lhs);
2572 -- Deal with the ancestor part of extension aggregates or with the
2573 -- discriminants of the root type.
2575 if Nkind (N) = N_Extension_Aggregate then
2577 A : constant Node_Id := Ancestor_Part (N);
2581 -- If the ancestor part is a subtype mark "T", we generate
2583 -- init-proc (T(tmp)); if T is constrained and
2584 -- init-proc (S(tmp)); where S applies an appropriate
2585 -- constraint if T is unconstrained
2587 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
2588 Ancestor_Is_Subtype_Mark := True;
2590 if Is_Constrained (Entity (A)) then
2591 Init_Typ := Entity (A);
2593 -- For an ancestor part given by an unconstrained type mark,
2594 -- create a subtype constrained by appropriate corresponding
2595 -- discriminant values coming from either associations of the
2596 -- aggregate or a constraint on a parent type. The subtype will
2597 -- be used to generate the correct default value for the
2600 elsif Has_Discriminants (Entity (A)) then
2602 Anc_Typ : constant Entity_Id := Entity (A);
2603 Anc_Constr : constant List_Id := New_List;
2604 Discrim : Entity_Id;
2605 Disc_Value : Node_Id;
2606 New_Indic : Node_Id;
2607 Subt_Decl : Node_Id;
2610 Discrim := First_Discriminant (Anc_Typ);
2611 while Present (Discrim) loop
2612 Disc_Value := Ancestor_Discriminant_Value (Discrim);
2613 Append_To (Anc_Constr, Disc_Value);
2614 Next_Discriminant (Discrim);
2618 Make_Subtype_Indication (Loc,
2619 Subtype_Mark => New_Occurrence_Of (Anc_Typ, Loc),
2621 Make_Index_Or_Discriminant_Constraint (Loc,
2622 Constraints => Anc_Constr));
2624 Init_Typ := Create_Itype (Ekind (Anc_Typ), N);
2627 Make_Subtype_Declaration (Loc,
2628 Defining_Identifier => Init_Typ,
2629 Subtype_Indication => New_Indic);
2631 -- Itypes must be analyzed with checks off Declaration
2632 -- must have a parent for proper handling of subsidiary
2635 Set_Parent (Subt_Decl, N);
2636 Analyze (Subt_Decl, Suppress => All_Checks);
2640 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2641 Set_Assignment_OK (Ref);
2643 if not Is_Interface (Init_Typ) then
2645 Build_Initialization_Call (Loc,
2648 In_Init_Proc => Within_Init_Proc,
2649 With_Default_Init => Has_Default_Init_Comps (N)
2651 Has_Task (Base_Type (Init_Typ))));
2653 if Is_Constrained (Entity (A))
2654 and then Has_Discriminants (Entity (A))
2656 Check_Ancestor_Discriminants (Entity (A));
2660 -- Handle calls to C++ constructors
2662 elsif Is_CPP_Constructor_Call (A) then
2663 Init_Typ := Etype (A);
2664 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2665 Set_Assignment_OK (Ref);
2668 Build_Initialization_Call (Loc,
2671 In_Init_Proc => Within_Init_Proc,
2672 With_Default_Init => Has_Default_Init_Comps (N),
2673 Constructor_Ref => A));
2675 -- Ada 2005 (AI-287): If the ancestor part is an aggregate of
2676 -- limited type, a recursive call expands the ancestor. Note that
2677 -- in the limited case, the ancestor part must be either a
2678 -- function call (possibly qualified, or wrapped in an unchecked
2679 -- conversion) or aggregate (definitely qualified).
2680 -- The ancestor part can also be a function call (that may be
2681 -- transformed into an explicit dereference) or a qualification
2684 elsif Is_Limited_Type (Etype (A))
2685 and then Nkind_In (Unqualify (A), N_Aggregate,
2686 N_Extension_Aggregate)
2688 Ancestor_Is_Expression := True;
2690 -- Set up finalization data for enclosing record, because
2691 -- controlled subcomponents of the ancestor part will be
2694 Gen_Ctrl_Actions_For_Aggr;
2697 Build_Record_Aggr_Code (
2699 Typ => Etype (Unqualify (A)),
2703 Is_Limited_Ancestor_Expansion => True));
2705 -- If the ancestor part is an expression "E", we generate
2709 -- In Ada 2005, this includes the case of a (possibly qualified)
2710 -- limited function call. The assignment will turn into a
2711 -- build-in-place function call (for further details, see
2712 -- Make_Build_In_Place_Call_In_Assignment).
2715 Ancestor_Is_Expression := True;
2716 Init_Typ := Etype (A);
2718 -- If the ancestor part is an aggregate, force its full
2719 -- expansion, which was delayed.
2721 if Nkind_In (Unqualify (A), N_Aggregate,
2722 N_Extension_Aggregate)
2724 Set_Analyzed (A, False);
2725 Set_Analyzed (Expression (A), False);
2728 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2729 Set_Assignment_OK (Ref);
2731 -- Make the assignment without usual controlled actions since
2732 -- we only want the post adjust but not the pre finalize here
2733 -- Add manual adjust when necessary.
2735 Assign := New_List (
2736 Make_OK_Assignment_Statement (Loc,
2739 Set_No_Ctrl_Actions (First (Assign));
2741 -- Assign the tag now to make sure that the dispatching call in
2742 -- the subsequent deep_adjust works properly (unless VM_Target,
2743 -- where tags are implicit).
2745 if Tagged_Type_Expansion then
2747 Make_OK_Assignment_Statement (Loc,
2749 Make_Selected_Component (Loc,
2750 Prefix => New_Copy_Tree (Target),
2753 (First_Tag_Component (Base_Type (Typ)), Loc)),
2756 Unchecked_Convert_To (RTE (RE_Tag),
2759 (Access_Disp_Table (Base_Type (Typ)))),
2762 Set_Assignment_OK (Name (Instr));
2763 Append_To (Assign, Instr);
2765 -- Ada 2005 (AI-251): If tagged type has progenitors we must
2766 -- also initialize tags of the secondary dispatch tables.
2768 if Has_Interfaces (Base_Type (Typ)) then
2770 (Typ => Base_Type (Typ),
2772 Stmts_List => Assign);
2776 -- Call Adjust manually
2778 if Needs_Finalization (Etype (A))
2779 and then not Is_Limited_Type (Etype (A))
2781 Append_List_To (Assign,
2783 Ref => New_Copy_Tree (Ref),
2785 Flist_Ref => New_Reference_To (
2786 RTE (RE_Global_Final_List), Loc),
2787 With_Attach => Make_Integer_Literal (Loc, 0)));
2791 Make_Unsuppress_Block (Loc, Name_Discriminant_Check, Assign));
2793 if Has_Discriminants (Init_Typ) then
2794 Check_Ancestor_Discriminants (Init_Typ);
2799 -- Generate assignments of hidden assignments. If the base type is an
2800 -- unchecked union, the discriminants are unknown to the back-end and
2801 -- absent from a value of the type, so assignments for them are not
2804 if Has_Discriminants (Typ)
2805 and then not Is_Unchecked_Union (Base_Type (Typ))
2807 Init_Hidden_Discriminants (Typ, L);
2810 -- Normal case (not an extension aggregate)
2813 -- Generate the discriminant expressions, component by component.
2814 -- If the base type is an unchecked union, the discriminants are
2815 -- unknown to the back-end and absent from a value of the type, so
2816 -- assignments for them are not emitted.
2818 if Has_Discriminants (Typ)
2819 and then not Is_Unchecked_Union (Base_Type (Typ))
2821 Init_Hidden_Discriminants (Typ, L);
2823 -- Generate discriminant init values for the visible discriminants
2826 Discriminant : Entity_Id;
2827 Discriminant_Value : Node_Id;
2830 Discriminant := First_Stored_Discriminant (Typ);
2831 while Present (Discriminant) loop
2833 Make_Selected_Component (Loc,
2834 Prefix => New_Copy_Tree (Target),
2835 Selector_Name => New_Occurrence_Of (Discriminant, Loc));
2837 Discriminant_Value :=
2838 Get_Discriminant_Value (
2841 Discriminant_Constraint (N_Typ));
2844 Make_OK_Assignment_Statement (Loc,
2846 Expression => New_Copy_Tree (Discriminant_Value));
2848 Set_No_Ctrl_Actions (Instr);
2849 Append_To (L, Instr);
2851 Next_Stored_Discriminant (Discriminant);
2857 -- For CPP types we generate an implicit call to the C++ default
2858 -- constructor to ensure the proper initialization of the _Tag
2861 if Is_CPP_Class (Root_Type (Typ))
2862 and then CPP_Num_Prims (Typ) > 0
2864 Invoke_Constructor : declare
2865 CPP_Parent : constant Entity_Id :=
2866 Enclosing_CPP_Parent (Typ);
2868 procedure Invoke_IC_Proc (T : Entity_Id);
2869 -- Recursive routine used to climb to parents. Required because
2870 -- parents must be initialized before descendants to ensure
2871 -- propagation of inherited C++ slots.
2873 --------------------
2874 -- Invoke_IC_Proc --
2875 --------------------
2877 procedure Invoke_IC_Proc (T : Entity_Id) is
2879 -- Avoid generating extra calls. Initialization required
2880 -- only for types defined from the level of derivation of
2881 -- type of the constructor and the type of the aggregate.
2883 if T = CPP_Parent then
2887 Invoke_IC_Proc (Etype (T));
2889 -- Generate call to the IC routine
2891 if Present (CPP_Init_Proc (T)) then
2893 Make_Procedure_Call_Statement (Loc,
2894 New_Reference_To (CPP_Init_Proc (T), Loc)));
2898 -- Start of processing for Invoke_Constructor
2901 -- Implicit invocation of the C++ constructor
2903 if Nkind (N) = N_Aggregate then
2905 Make_Procedure_Call_Statement (Loc,
2908 (Base_Init_Proc (CPP_Parent), Loc),
2909 Parameter_Associations => New_List (
2910 Unchecked_Convert_To (CPP_Parent,
2911 New_Copy_Tree (Lhs)))));
2914 Invoke_IC_Proc (Typ);
2915 end Invoke_Constructor;
2918 -- Generate the assignments, component by component
2920 -- tmp.comp1 := Expr1_From_Aggr;
2921 -- tmp.comp2 := Expr2_From_Aggr;
2924 Comp := First (Component_Associations (N));
2925 while Present (Comp) loop
2926 Selector := Entity (First (Choices (Comp)));
2930 if Is_CPP_Constructor_Call (Expression (Comp)) then
2932 Build_Initialization_Call (Loc,
2933 Id_Ref => Make_Selected_Component (Loc,
2934 Prefix => New_Copy_Tree (Target),
2936 New_Occurrence_Of (Selector, Loc)),
2937 Typ => Etype (Selector),
2939 With_Default_Init => True,
2940 Constructor_Ref => Expression (Comp)));
2942 -- Ada 2005 (AI-287): For each default-initialized component generate
2943 -- a call to the corresponding IP subprogram if available.
2945 elsif Box_Present (Comp)
2946 and then Has_Non_Null_Base_Init_Proc (Etype (Selector))
2948 if Ekind (Selector) /= E_Discriminant then
2949 Gen_Ctrl_Actions_For_Aggr;
2952 -- Ada 2005 (AI-287): If the component type has tasks then
2953 -- generate the activation chain and master entities (except
2954 -- in case of an allocator because in that case these entities
2955 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
2958 Ctype : constant Entity_Id := Etype (Selector);
2959 Inside_Allocator : Boolean := False;
2960 P : Node_Id := Parent (N);
2963 if Is_Task_Type (Ctype) or else Has_Task (Ctype) then
2964 while Present (P) loop
2965 if Nkind (P) = N_Allocator then
2966 Inside_Allocator := True;
2973 if not Inside_Init_Proc and not Inside_Allocator then
2974 Build_Activation_Chain_Entity (N);
2980 Build_Initialization_Call (Loc,
2981 Id_Ref => Make_Selected_Component (Loc,
2982 Prefix => New_Copy_Tree (Target),
2984 New_Occurrence_Of (Selector, Loc)),
2985 Typ => Etype (Selector),
2987 With_Default_Init => True));
2989 -- Prepare for component assignment
2991 elsif Ekind (Selector) /= E_Discriminant
2992 or else Nkind (N) = N_Extension_Aggregate
2994 -- All the discriminants have now been assigned
2996 -- This is now a good moment to initialize and attach all the
2997 -- controllers. Their position may depend on the discriminants.
2999 if Ekind (Selector) /= E_Discriminant then
3000 Gen_Ctrl_Actions_For_Aggr;
3003 Comp_Type := Underlying_Type (Etype (Selector));
3005 Make_Selected_Component (Loc,
3006 Prefix => New_Copy_Tree (Target),
3007 Selector_Name => New_Occurrence_Of (Selector, Loc));
3009 if Nkind (Expression (Comp)) = N_Qualified_Expression then
3010 Expr_Q := Expression (Expression (Comp));
3012 Expr_Q := Expression (Comp);
3015 -- The controller is the one of the parent type defining the
3016 -- component (in case of inherited components).
3018 if Needs_Finalization (Comp_Type) then
3019 Internal_Final_List :=
3020 Make_Selected_Component (Loc,
3021 Prefix => Convert_To
3022 (Scope (Original_Record_Component (Selector)),
3023 New_Copy_Tree (Target)),
3024 Selector_Name => Make_Identifier (Loc, Name_uController));
3026 Internal_Final_List :=
3027 Make_Selected_Component (Loc,
3028 Prefix => Internal_Final_List,
3029 Selector_Name => Make_Identifier (Loc, Name_F));
3031 -- The internal final list can be part of a constant object
3033 Set_Assignment_OK (Internal_Final_List);
3036 Internal_Final_List := Empty;
3039 -- Now either create the assignment or generate the code for the
3040 -- inner aggregate top-down.
3042 if Is_Delayed_Aggregate (Expr_Q) then
3044 -- We have the following case of aggregate nesting inside
3045 -- an object declaration:
3047 -- type Arr_Typ is array (Integer range <>) of ...;
3049 -- type Rec_Typ (...) is record
3050 -- Obj_Arr_Typ : Arr_Typ (A .. B);
3053 -- Obj_Rec_Typ : Rec_Typ := (...,
3054 -- Obj_Arr_Typ => (X => (...), Y => (...)));
3056 -- The length of the ranges of the aggregate and Obj_Add_Typ
3057 -- are equal (B - A = Y - X), but they do not coincide (X /=
3058 -- A and B /= Y). This case requires array sliding which is
3059 -- performed in the following manner:
3061 -- subtype Arr_Sub is Arr_Typ (X .. Y);
3063 -- Temp (X) := (...);
3065 -- Temp (Y) := (...);
3066 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
3068 if Ekind (Comp_Type) = E_Array_Subtype
3069 and then Is_Int_Range_Bounds (Aggregate_Bounds (Expr_Q))
3070 and then Is_Int_Range_Bounds (First_Index (Comp_Type))
3072 Compatible_Int_Bounds
3073 (Agg_Bounds => Aggregate_Bounds (Expr_Q),
3074 Typ_Bounds => First_Index (Comp_Type))
3076 -- Create the array subtype with bounds equal to those of
3077 -- the corresponding aggregate.
3080 SubE : constant Entity_Id := Make_Temporary (Loc, 'T');
3082 SubD : constant Node_Id :=
3083 Make_Subtype_Declaration (Loc,
3084 Defining_Identifier => SubE,
3085 Subtype_Indication =>
3086 Make_Subtype_Indication (Loc,
3089 (Etype (Comp_Type), Loc),
3091 Make_Index_Or_Discriminant_Constraint
3093 Constraints => New_List (
3095 (Aggregate_Bounds (Expr_Q))))));
3097 -- Create a temporary array of the above subtype which
3098 -- will be used to capture the aggregate assignments.
3100 TmpE : constant Entity_Id := Make_Temporary (Loc, 'A', N);
3102 TmpD : constant Node_Id :=
3103 Make_Object_Declaration (Loc,
3104 Defining_Identifier => TmpE,
3105 Object_Definition =>
3106 New_Reference_To (SubE, Loc));
3109 Set_No_Initialization (TmpD);
3110 Append_To (L, SubD);
3111 Append_To (L, TmpD);
3113 -- Expand aggregate into assignments to the temp array
3116 Late_Expansion (Expr_Q, Comp_Type,
3117 New_Reference_To (TmpE, Loc), Internal_Final_List));
3122 Make_Assignment_Statement (Loc,
3123 Name => New_Copy_Tree (Comp_Expr),
3124 Expression => New_Reference_To (TmpE, Loc)));
3126 -- Do not pass the original aggregate to Gigi as is,
3127 -- since it will potentially clobber the front or the end
3128 -- of the array. Setting the expression to empty is safe
3129 -- since all aggregates are expanded into assignments.
3131 if Present (Obj) then
3132 Set_Expression (Parent (Obj), Empty);
3136 -- Normal case (sliding not required)
3140 Late_Expansion (Expr_Q, Comp_Type, Comp_Expr,
3141 Internal_Final_List));
3144 -- Expr_Q is not delayed aggregate
3147 if Has_Discriminants (Typ) then
3148 Replace_Discriminants (Expr_Q);
3152 Make_OK_Assignment_Statement (Loc,
3154 Expression => Expr_Q);
3156 Set_No_Ctrl_Actions (Instr);
3157 Append_To (L, Instr);
3159 -- Adjust the tag if tagged (because of possible view
3160 -- conversions), unless compiling for a VM where tags are
3163 -- tmp.comp._tag := comp_typ'tag;
3165 if Is_Tagged_Type (Comp_Type)
3166 and then Tagged_Type_Expansion
3169 Make_OK_Assignment_Statement (Loc,
3171 Make_Selected_Component (Loc,
3172 Prefix => New_Copy_Tree (Comp_Expr),
3175 (First_Tag_Component (Comp_Type), Loc)),
3178 Unchecked_Convert_To (RTE (RE_Tag),
3180 (Node (First_Elmt (Access_Disp_Table (Comp_Type))),
3183 Append_To (L, Instr);
3186 -- Adjust and Attach the component to the proper controller
3188 -- Adjust (tmp.comp);
3189 -- Attach_To_Final_List (tmp.comp,
3190 -- comp_typ (tmp)._record_controller.f)
3192 if Needs_Finalization (Comp_Type)
3193 and then not Is_Limited_Type (Comp_Type)
3197 Ref => New_Copy_Tree (Comp_Expr),
3199 Flist_Ref => Internal_Final_List,
3200 With_Attach => Make_Integer_Literal (Loc, 1)));
3206 elsif Ekind (Selector) = E_Discriminant
3207 and then Nkind (N) /= N_Extension_Aggregate
3208 and then Nkind (Parent (N)) = N_Component_Association
3209 and then Is_Constrained (Typ)
3211 -- We must check that the discriminant value imposed by the
3212 -- context is the same as the value given in the subaggregate,
3213 -- because after the expansion into assignments there is no
3214 -- record on which to perform a regular discriminant check.
3221 D_Val := First_Elmt (Discriminant_Constraint (Typ));
3222 Disc := First_Discriminant (Typ);
3223 while Chars (Disc) /= Chars (Selector) loop
3224 Next_Discriminant (Disc);
3228 pragma Assert (Present (D_Val));
3230 -- This check cannot performed for components that are
3231 -- constrained by a current instance, because this is not a
3232 -- value that can be compared with the actual constraint.
3234 if Nkind (Node (D_Val)) /= N_Attribute_Reference
3235 or else not Is_Entity_Name (Prefix (Node (D_Val)))
3236 or else not Is_Type (Entity (Prefix (Node (D_Val))))
3239 Make_Raise_Constraint_Error (Loc,
3242 Left_Opnd => New_Copy_Tree (Node (D_Val)),
3243 Right_Opnd => Expression (Comp)),
3244 Reason => CE_Discriminant_Check_Failed));
3247 -- Find self-reference in previous discriminant assignment,
3248 -- and replace with proper expression.
3255 while Present (Ass) loop
3256 if Nkind (Ass) = N_Assignment_Statement
3257 and then Nkind (Name (Ass)) = N_Selected_Component
3258 and then Chars (Selector_Name (Name (Ass))) =
3262 (Ass, New_Copy_Tree (Expression (Comp)));
3275 -- If the type is tagged, the tag needs to be initialized (unless
3276 -- compiling for the Java VM where tags are implicit). It is done
3277 -- late in the initialization process because in some cases, we call
3278 -- the init proc of an ancestor which will not leave out the right tag
3280 if Ancestor_Is_Expression then
3283 -- For CPP types we generated a call to the C++ default constructor
3284 -- before the components have been initialized to ensure the proper
3285 -- initialization of the _Tag component (see above).
3287 elsif Is_CPP_Class (Typ) then
3290 elsif Is_Tagged_Type (Typ) and then Tagged_Type_Expansion then
3292 Make_OK_Assignment_Statement (Loc,
3294 Make_Selected_Component (Loc,
3295 Prefix => New_Copy_Tree (Target),
3298 (First_Tag_Component (Base_Type (Typ)), Loc)),
3301 Unchecked_Convert_To (RTE (RE_Tag),
3303 (Node (First_Elmt (Access_Disp_Table (Base_Type (Typ)))),
3306 Append_To (L, Instr);
3308 -- Ada 2005 (AI-251): If the tagged type has been derived from
3309 -- abstract interfaces we must also initialize the tags of the
3310 -- secondary dispatch tables.
3312 if Has_Interfaces (Base_Type (Typ)) then
3314 (Typ => Base_Type (Typ),
3320 -- If the controllers have not been initialized yet (by lack of non-
3321 -- discriminant components), let's do it now.
3323 Gen_Ctrl_Actions_For_Aggr;
3326 end Build_Record_Aggr_Code;
3328 -------------------------------
3329 -- Convert_Aggr_In_Allocator --
3330 -------------------------------
3332 procedure Convert_Aggr_In_Allocator
3337 Loc : constant Source_Ptr := Sloc (Aggr);
3338 Typ : constant Entity_Id := Etype (Aggr);
3339 Temp : constant Entity_Id := Defining_Identifier (Decl);
3341 Occ : constant Node_Id :=
3342 Unchecked_Convert_To (Typ,
3343 Make_Explicit_Dereference (Loc,
3344 New_Reference_To (Temp, Loc)));
3346 Access_Type : constant Entity_Id := Etype (Temp);
3350 -- If the allocator is for an access discriminant, there is no
3351 -- finalization list for the anonymous access type, and the eventual
3352 -- finalization of the object is handled through the coextension
3353 -- mechanism. If the enclosing object is not dynamically allocated,
3354 -- the access discriminant is itself placed on the stack. Otherwise,
3355 -- some other finalization list is used (see exp_ch4.adb).
3357 -- Decl has been inserted in the code ahead of the allocator, using
3358 -- Insert_Actions. We use Insert_Actions below as well, to ensure that
3359 -- subsequent insertions are done in the proper order. Using (for
3360 -- example) Insert_Actions_After to place the expanded aggregate
3361 -- immediately after Decl may lead to out-of-order references if the
3362 -- allocator has generated a finalization list, as when the designated
3363 -- object is controlled and there is an open transient scope.
3365 if Ekind (Access_Type) = E_Anonymous_Access_Type
3366 and then Nkind (Associated_Node_For_Itype (Access_Type)) =
3367 N_Discriminant_Specification
3371 elsif Needs_Finalization (Typ) then
3372 Flist := Find_Final_List (Access_Type);
3374 -- Otherwise there are no controlled actions to be performed.
3380 if Is_Array_Type (Typ) then
3381 Convert_Array_Aggr_In_Allocator (Decl, Aggr, Occ);
3383 elsif Has_Default_Init_Comps (Aggr) then
3385 L : constant List_Id := New_List;
3386 Init_Stmts : List_Id;
3393 Associated_Final_Chain (Base_Type (Access_Type)));
3395 -- ??? Dubious actual for Obj: expect 'the original object being
3398 if Has_Task (Typ) then
3399 Build_Task_Allocate_Block_With_Init_Stmts (L, Aggr, Init_Stmts);
3400 Insert_Actions (Alloc, L);
3402 Insert_Actions (Alloc, Init_Stmts);
3407 Insert_Actions (Alloc,
3409 (Aggr, Typ, Occ, Flist,
3410 Associated_Final_Chain (Base_Type (Access_Type))));
3412 -- ??? Dubious actual for Obj: expect 'the original object being
3416 end Convert_Aggr_In_Allocator;
3418 --------------------------------
3419 -- Convert_Aggr_In_Assignment --
3420 --------------------------------
3422 procedure Convert_Aggr_In_Assignment (N : Node_Id) is
3423 Aggr : Node_Id := Expression (N);
3424 Typ : constant Entity_Id := Etype (Aggr);
3425 Occ : constant Node_Id := New_Copy_Tree (Name (N));
3428 if Nkind (Aggr) = N_Qualified_Expression then
3429 Aggr := Expression (Aggr);
3432 Insert_Actions_After (N,
3435 Find_Final_List (Typ, New_Copy_Tree (Occ))));
3436 end Convert_Aggr_In_Assignment;
3438 ---------------------------------
3439 -- Convert_Aggr_In_Object_Decl --
3440 ---------------------------------
3442 procedure Convert_Aggr_In_Object_Decl (N : Node_Id) is
3443 Obj : constant Entity_Id := Defining_Identifier (N);
3444 Aggr : Node_Id := Expression (N);
3445 Loc : constant Source_Ptr := Sloc (Aggr);
3446 Typ : constant Entity_Id := Etype (Aggr);
3447 Occ : constant Node_Id := New_Occurrence_Of (Obj, Loc);
3449 function Discriminants_Ok return Boolean;
3450 -- If the object type is constrained, the discriminants in the
3451 -- aggregate must be checked against the discriminants of the subtype.
3452 -- This cannot be done using Apply_Discriminant_Checks because after
3453 -- expansion there is no aggregate left to check.
3455 ----------------------
3456 -- Discriminants_Ok --
3457 ----------------------
3459 function Discriminants_Ok return Boolean is
3460 Cond : Node_Id := Empty;
3469 D := First_Discriminant (Typ);
3470 Disc1 := First_Elmt (Discriminant_Constraint (Typ));
3471 Disc2 := First_Elmt (Discriminant_Constraint (Etype (Obj)));
3472 while Present (Disc1) and then Present (Disc2) loop
3473 Val1 := Node (Disc1);
3474 Val2 := Node (Disc2);
3476 if not Is_OK_Static_Expression (Val1)
3477 or else not Is_OK_Static_Expression (Val2)
3479 Check := Make_Op_Ne (Loc,
3480 Left_Opnd => Duplicate_Subexpr (Val1),
3481 Right_Opnd => Duplicate_Subexpr (Val2));
3487 Cond := Make_Or_Else (Loc,
3489 Right_Opnd => Check);
3492 elsif Expr_Value (Val1) /= Expr_Value (Val2) then
3493 Apply_Compile_Time_Constraint_Error (Aggr,
3494 Msg => "incorrect value for discriminant&?",
3495 Reason => CE_Discriminant_Check_Failed,
3500 Next_Discriminant (D);
3505 -- If any discriminant constraint is non-static, emit a check
3507 if Present (Cond) then
3509 Make_Raise_Constraint_Error (Loc,
3511 Reason => CE_Discriminant_Check_Failed));
3515 end Discriminants_Ok;
3517 -- Start of processing for Convert_Aggr_In_Object_Decl
3520 Set_Assignment_OK (Occ);
3522 if Nkind (Aggr) = N_Qualified_Expression then
3523 Aggr := Expression (Aggr);
3526 if Has_Discriminants (Typ)
3527 and then Typ /= Etype (Obj)
3528 and then Is_Constrained (Etype (Obj))
3529 and then not Discriminants_Ok
3534 -- If the context is an extended return statement, it has its own
3535 -- finalization machinery (i.e. works like a transient scope) and
3536 -- we do not want to create an additional one, because objects on
3537 -- the finalization list of the return must be moved to the caller's
3538 -- finalization list to complete the return.
3540 -- However, if the aggregate is limited, it is built in place, and the
3541 -- controlled components are not assigned to intermediate temporaries
3542 -- so there is no need for a transient scope in this case either.
3544 if Requires_Transient_Scope (Typ)
3545 and then Ekind (Current_Scope) /= E_Return_Statement
3546 and then not Is_Limited_Type (Typ)
3548 Establish_Transient_Scope
3551 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
3554 Insert_Actions_After (N, Late_Expansion (Aggr, Typ, Occ, Obj => Obj));
3555 Set_No_Initialization (N);
3556 Initialize_Discriminants (N, Typ);
3557 end Convert_Aggr_In_Object_Decl;
3559 -------------------------------------
3560 -- Convert_Array_Aggr_In_Allocator --
3561 -------------------------------------
3563 procedure Convert_Array_Aggr_In_Allocator
3568 Aggr_Code : List_Id;
3569 Typ : constant Entity_Id := Etype (Aggr);
3570 Ctyp : constant Entity_Id := Component_Type (Typ);
3573 -- The target is an explicit dereference of the allocated object.
3574 -- Generate component assignments to it, as for an aggregate that
3575 -- appears on the right-hand side of an assignment statement.
3578 Build_Array_Aggr_Code (Aggr,
3580 Index => First_Index (Typ),
3582 Scalar_Comp => Is_Scalar_Type (Ctyp));
3584 Insert_Actions_After (Decl, Aggr_Code);
3585 end Convert_Array_Aggr_In_Allocator;
3587 ----------------------------
3588 -- Convert_To_Assignments --
3589 ----------------------------
3591 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id) is
3592 Loc : constant Source_Ptr := Sloc (N);
3597 Target_Expr : Node_Id;
3598 Parent_Kind : Node_Kind;
3599 Unc_Decl : Boolean := False;
3600 Parent_Node : Node_Id;
3603 pragma Assert (not Is_Static_Dispatch_Table_Aggregate (N));
3604 pragma Assert (Is_Record_Type (Typ));
3606 Parent_Node := Parent (N);
3607 Parent_Kind := Nkind (Parent_Node);
3609 if Parent_Kind = N_Qualified_Expression then
3611 -- Check if we are in a unconstrained declaration because in this
3612 -- case the current delayed expansion mechanism doesn't work when
3613 -- the declared object size depend on the initializing expr.
3616 Parent_Node := Parent (Parent_Node);
3617 Parent_Kind := Nkind (Parent_Node);
3619 if Parent_Kind = N_Object_Declaration then
3621 not Is_Entity_Name (Object_Definition (Parent_Node))
3622 or else Has_Discriminants
3623 (Entity (Object_Definition (Parent_Node)))
3624 or else Is_Class_Wide_Type
3625 (Entity (Object_Definition (Parent_Node)));
3630 -- Just set the Delay flag in the cases where the transformation will be
3631 -- done top down from above.
3635 -- Internal aggregate (transformed when expanding the parent)
3637 or else Parent_Kind = N_Aggregate
3638 or else Parent_Kind = N_Extension_Aggregate
3639 or else Parent_Kind = N_Component_Association
3641 -- Allocator (see Convert_Aggr_In_Allocator)
3643 or else Parent_Kind = N_Allocator
3645 -- Object declaration (see Convert_Aggr_In_Object_Decl)
3647 or else (Parent_Kind = N_Object_Declaration and then not Unc_Decl)
3649 -- Safe assignment (see Convert_Aggr_Assignments). So far only the
3650 -- assignments in init procs are taken into account.
3652 or else (Parent_Kind = N_Assignment_Statement
3653 and then Inside_Init_Proc)
3655 -- (Ada 2005) An inherently limited type in a return statement,
3656 -- which will be handled in a build-in-place fashion, and may be
3657 -- rewritten as an extended return and have its own finalization
3658 -- machinery. In the case of a simple return, the aggregate needs
3659 -- to be delayed until the scope for the return statement has been
3660 -- created, so that any finalization chain will be associated with
3661 -- that scope. For extended returns, we delay expansion to avoid the
3662 -- creation of an unwanted transient scope that could result in
3663 -- premature finalization of the return object (which is built in
3664 -- in place within the caller's scope).
3667 (Is_Immutably_Limited_Type (Typ)
3669 (Nkind (Parent (Parent_Node)) = N_Extended_Return_Statement
3670 or else Nkind (Parent_Node) = N_Simple_Return_Statement))
3672 Set_Expansion_Delayed (N);
3676 if Requires_Transient_Scope (Typ) then
3677 Establish_Transient_Scope
3679 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
3682 -- If the aggregate is non-limited, create a temporary. If it is limited
3683 -- and the context is an assignment, this is a subaggregate for an
3684 -- enclosing aggregate being expanded. It must be built in place, so use
3685 -- the target of the current assignment.
3687 if Is_Limited_Type (Typ)
3688 and then Nkind (Parent (N)) = N_Assignment_Statement
3690 Target_Expr := New_Copy_Tree (Name (Parent (N)));
3692 (Parent (N), Build_Record_Aggr_Code (N, Typ, Target_Expr));
3693 Rewrite (Parent (N), Make_Null_Statement (Loc));
3696 Temp := Make_Temporary (Loc, 'A', N);
3698 -- If the type inherits unknown discriminants, use the view with
3699 -- known discriminants if available.
3701 if Has_Unknown_Discriminants (Typ)
3702 and then Present (Underlying_Record_View (Typ))
3704 T := Underlying_Record_View (Typ);
3710 Make_Object_Declaration (Loc,
3711 Defining_Identifier => Temp,
3712 Object_Definition => New_Occurrence_Of (T, Loc));
3714 Set_No_Initialization (Instr);
3715 Insert_Action (N, Instr);
3716 Initialize_Discriminants (Instr, T);
3717 Target_Expr := New_Occurrence_Of (Temp, Loc);
3718 Insert_Actions (N, Build_Record_Aggr_Code (N, T, Target_Expr));
3719 Rewrite (N, New_Occurrence_Of (Temp, Loc));
3720 Analyze_And_Resolve (N, T);
3722 end Convert_To_Assignments;
3724 ---------------------------
3725 -- Convert_To_Positional --
3726 ---------------------------
3728 procedure Convert_To_Positional
3730 Max_Others_Replicate : Nat := 5;
3731 Handle_Bit_Packed : Boolean := False)
3733 Typ : constant Entity_Id := Etype (N);
3735 Static_Components : Boolean := True;
3737 procedure Check_Static_Components;
3738 -- Check whether all components of the aggregate are compile-time known
3739 -- values, and can be passed as is to the back-end without further
3745 Ixb : Node_Id) return Boolean;
3746 -- Convert the aggregate into a purely positional form if possible. On
3747 -- entry the bounds of all dimensions are known to be static, and the
3748 -- total number of components is safe enough to expand.
3750 function Is_Flat (N : Node_Id; Dims : Int) return Boolean;
3751 -- Return True iff the array N is flat (which is not trivial in the case
3752 -- of multidimensional aggregates).
3754 -----------------------------
3755 -- Check_Static_Components --
3756 -----------------------------
3758 procedure Check_Static_Components is
3762 Static_Components := True;
3764 if Nkind (N) = N_String_Literal then
3767 elsif Present (Expressions (N)) then
3768 Expr := First (Expressions (N));
3769 while Present (Expr) loop
3770 if Nkind (Expr) /= N_Aggregate
3771 or else not Compile_Time_Known_Aggregate (Expr)
3772 or else Expansion_Delayed (Expr)
3774 Static_Components := False;
3782 if Nkind (N) = N_Aggregate
3783 and then Present (Component_Associations (N))
3785 Expr := First (Component_Associations (N));
3786 while Present (Expr) loop
3787 if Nkind_In (Expression (Expr), N_Integer_Literal,
3792 elsif Is_Entity_Name (Expression (Expr))
3793 and then Present (Entity (Expression (Expr)))
3794 and then Ekind (Entity (Expression (Expr))) =
3795 E_Enumeration_Literal
3799 elsif Nkind (Expression (Expr)) /= N_Aggregate
3800 or else not Compile_Time_Known_Aggregate (Expression (Expr))
3801 or else Expansion_Delayed (Expression (Expr))
3803 Static_Components := False;
3810 end Check_Static_Components;
3819 Ixb : Node_Id) return Boolean
3821 Loc : constant Source_Ptr := Sloc (N);
3822 Blo : constant Node_Id := Type_Low_Bound (Etype (Ixb));
3823 Lo : constant Node_Id := Type_Low_Bound (Etype (Ix));
3824 Hi : constant Node_Id := Type_High_Bound (Etype (Ix));
3829 if Nkind (Original_Node (N)) = N_String_Literal then
3833 if not Compile_Time_Known_Value (Lo)
3834 or else not Compile_Time_Known_Value (Hi)
3839 Lov := Expr_Value (Lo);
3840 Hiv := Expr_Value (Hi);
3843 or else not Compile_Time_Known_Value (Blo)
3848 -- Determine if set of alternatives is suitable for conversion and
3849 -- build an array containing the values in sequence.
3852 Vals : array (UI_To_Int (Lov) .. UI_To_Int (Hiv))
3853 of Node_Id := (others => Empty);
3854 -- The values in the aggregate sorted appropriately
3857 -- Same data as Vals in list form
3860 -- Used to validate Max_Others_Replicate limit
3863 Num : Int := UI_To_Int (Lov);
3869 if Present (Expressions (N)) then
3870 Elmt := First (Expressions (N));
3871 while Present (Elmt) loop
3872 if Nkind (Elmt) = N_Aggregate
3873 and then Present (Next_Index (Ix))
3875 not Flatten (Elmt, Next_Index (Ix), Next_Index (Ixb))
3880 Vals (Num) := Relocate_Node (Elmt);
3887 if No (Component_Associations (N)) then
3891 Elmt := First (Component_Associations (N));
3893 if Nkind (Expression (Elmt)) = N_Aggregate then
3894 if Present (Next_Index (Ix))
3897 (Expression (Elmt), Next_Index (Ix), Next_Index (Ixb))
3903 Component_Loop : while Present (Elmt) loop
3904 Choice := First (Choices (Elmt));
3905 Choice_Loop : while Present (Choice) loop
3907 -- If we have an others choice, fill in the missing elements
3908 -- subject to the limit established by Max_Others_Replicate.
3910 if Nkind (Choice) = N_Others_Choice then
3913 for J in Vals'Range loop
3914 if No (Vals (J)) then
3915 Vals (J) := New_Copy_Tree (Expression (Elmt));
3916 Rep_Count := Rep_Count + 1;
3918 -- Check for maximum others replication. Note that
3919 -- we skip this test if either of the restrictions
3920 -- No_Elaboration_Code or No_Implicit_Loops is
3921 -- active, if this is a preelaborable unit or a
3922 -- predefined unit. This ensures that predefined
3923 -- units get the same level of constant folding in
3924 -- Ada 95 and Ada 05, where their categorization
3928 P : constant Entity_Id :=
3929 Cunit_Entity (Current_Sem_Unit);
3932 -- Check if duplication OK and if so continue
3935 if Restriction_Active (No_Elaboration_Code)
3936 or else Restriction_Active (No_Implicit_Loops)
3937 or else Is_Preelaborated (P)
3938 or else (Ekind (P) = E_Package_Body
3940 Is_Preelaborated (Spec_Entity (P)))
3942 Is_Predefined_File_Name
3943 (Unit_File_Name (Get_Source_Unit (P)))
3947 -- If duplication not OK, then we return False
3948 -- if the replication count is too high
3950 elsif Rep_Count > Max_Others_Replicate then
3953 -- Continue on if duplication not OK, but the
3954 -- replication count is not excessive.
3963 exit Component_Loop;
3965 -- Case of a subtype mark, identifier or expanded name
3967 elsif Is_Entity_Name (Choice)
3968 and then Is_Type (Entity (Choice))
3970 Lo := Type_Low_Bound (Etype (Choice));
3971 Hi := Type_High_Bound (Etype (Choice));
3973 -- Case of subtype indication
3975 elsif Nkind (Choice) = N_Subtype_Indication then
3976 Lo := Low_Bound (Range_Expression (Constraint (Choice)));
3977 Hi := High_Bound (Range_Expression (Constraint (Choice)));
3981 elsif Nkind (Choice) = N_Range then
3982 Lo := Low_Bound (Choice);
3983 Hi := High_Bound (Choice);
3985 -- Normal subexpression case
3987 else pragma Assert (Nkind (Choice) in N_Subexpr);
3988 if not Compile_Time_Known_Value (Choice) then
3992 Choice_Index := UI_To_Int (Expr_Value (Choice));
3993 if Choice_Index in Vals'Range then
3994 Vals (Choice_Index) :=
3995 New_Copy_Tree (Expression (Elmt));
3999 -- Choice is statically out-of-range, will be
4000 -- rewritten to raise Constraint_Error.
4007 -- Range cases merge with Lo,Hi set
4009 if not Compile_Time_Known_Value (Lo)
4011 not Compile_Time_Known_Value (Hi)
4015 for J in UI_To_Int (Expr_Value (Lo)) ..
4016 UI_To_Int (Expr_Value (Hi))
4018 Vals (J) := New_Copy_Tree (Expression (Elmt));
4024 end loop Choice_Loop;
4027 end loop Component_Loop;
4029 -- If we get here the conversion is possible
4032 for J in Vals'Range loop
4033 Append (Vals (J), Vlist);
4036 Rewrite (N, Make_Aggregate (Loc, Expressions => Vlist));
4037 Set_Aggregate_Bounds (N, Aggregate_Bounds (Original_Node (N)));
4046 function Is_Flat (N : Node_Id; Dims : Int) return Boolean is
4053 elsif Nkind (N) = N_Aggregate then
4054 if Present (Component_Associations (N)) then
4058 Elmt := First (Expressions (N));
4059 while Present (Elmt) loop
4060 if not Is_Flat (Elmt, Dims - 1) then
4074 -- Start of processing for Convert_To_Positional
4077 -- Ada 2005 (AI-287): Do not convert in case of default initialized
4078 -- components because in this case will need to call the corresponding
4081 if Has_Default_Init_Comps (N) then
4085 if Is_Flat (N, Number_Dimensions (Typ)) then
4089 if Is_Bit_Packed_Array (Typ)
4090 and then not Handle_Bit_Packed
4095 -- Do not convert to positional if controlled components are involved
4096 -- since these require special processing
4098 if Has_Controlled_Component (Typ) then
4102 Check_Static_Components;
4104 -- If the size is known, or all the components are static, try to
4105 -- build a fully positional aggregate.
4107 -- The size of the type may not be known for an aggregate with
4108 -- discriminated array components, but if the components are static
4109 -- it is still possible to verify statically that the length is
4110 -- compatible with the upper bound of the type, and therefore it is
4111 -- worth flattening such aggregates as well.
4113 -- For now the back-end expands these aggregates into individual
4114 -- assignments to the target anyway, but it is conceivable that
4115 -- it will eventually be able to treat such aggregates statically???
4117 if Aggr_Size_OK (N, Typ)
4118 and then Flatten (N, First_Index (Typ), First_Index (Base_Type (Typ)))
4120 if Static_Components then
4121 Set_Compile_Time_Known_Aggregate (N);
4122 Set_Expansion_Delayed (N, False);
4125 Analyze_And_Resolve (N, Typ);
4127 end Convert_To_Positional;
4129 ----------------------------
4130 -- Expand_Array_Aggregate --
4131 ----------------------------
4133 -- Array aggregate expansion proceeds as follows:
4135 -- 1. If requested we generate code to perform all the array aggregate
4136 -- bound checks, specifically
4138 -- (a) Check that the index range defined by aggregate bounds is
4139 -- compatible with corresponding index subtype.
4141 -- (b) If an others choice is present check that no aggregate
4142 -- index is outside the bounds of the index constraint.
4144 -- (c) For multidimensional arrays make sure that all subaggregates
4145 -- corresponding to the same dimension have the same bounds.
4147 -- 2. Check for packed array aggregate which can be converted to a
4148 -- constant so that the aggregate disappeares completely.
4150 -- 3. Check case of nested aggregate. Generally nested aggregates are
4151 -- handled during the processing of the parent aggregate.
4153 -- 4. Check if the aggregate can be statically processed. If this is the
4154 -- case pass it as is to Gigi. Note that a necessary condition for
4155 -- static processing is that the aggregate be fully positional.
4157 -- 5. If in place aggregate expansion is possible (i.e. no need to create
4158 -- a temporary) then mark the aggregate as such and return. Otherwise
4159 -- create a new temporary and generate the appropriate initialization
4162 procedure Expand_Array_Aggregate (N : Node_Id) is
4163 Loc : constant Source_Ptr := Sloc (N);
4165 Typ : constant Entity_Id := Etype (N);
4166 Ctyp : constant Entity_Id := Component_Type (Typ);
4167 -- Typ is the correct constrained array subtype of the aggregate
4168 -- Ctyp is the corresponding component type.
4170 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
4171 -- Number of aggregate index dimensions
4173 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id;
4174 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id;
4175 -- Low and High bounds of the constraint for each aggregate index
4177 Aggr_Index_Typ : array (1 .. Aggr_Dimension) of Entity_Id;
4178 -- The type of each index
4180 Maybe_In_Place_OK : Boolean;
4181 -- If the type is neither controlled nor packed and the aggregate
4182 -- is the expression in an assignment, assignment in place may be
4183 -- possible, provided other conditions are met on the LHS.
4185 Others_Present : array (1 .. Aggr_Dimension) of Boolean :=
4187 -- If Others_Present (J) is True, then there is an others choice
4188 -- in one of the sub-aggregates of N at dimension J.
4190 procedure Build_Constrained_Type (Positional : Boolean);
4191 -- If the subtype is not static or unconstrained, build a constrained
4192 -- type using the computable sizes of the aggregate and its sub-
4195 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id);
4196 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
4199 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos);
4200 -- Checks that in a multi-dimensional array aggregate all subaggregates
4201 -- corresponding to the same dimension have the same bounds.
4202 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4203 -- corresponding to the sub-aggregate.
4205 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos);
4206 -- Computes the values of array Others_Present. Sub_Aggr is the
4207 -- array sub-aggregate we start the computation from. Dim is the
4208 -- dimension corresponding to the sub-aggregate.
4210 function In_Place_Assign_OK return Boolean;
4211 -- Simple predicate to determine whether an aggregate assignment can
4212 -- be done in place, because none of the new values can depend on the
4213 -- components of the target of the assignment.
4215 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos);
4216 -- Checks that if an others choice is present in any sub-aggregate no
4217 -- aggregate index is outside the bounds of the index constraint.
4218 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4219 -- corresponding to the sub-aggregate.
4221 function Safe_Left_Hand_Side (N : Node_Id) return Boolean;
4222 -- In addition to Maybe_In_Place_OK, in order for an aggregate to be
4223 -- built directly into the target of the assignment it must be free
4226 ----------------------------
4227 -- Build_Constrained_Type --
4228 ----------------------------
4230 procedure Build_Constrained_Type (Positional : Boolean) is
4231 Loc : constant Source_Ptr := Sloc (N);
4232 Agg_Type : constant Entity_Id := Make_Temporary (Loc, 'A');
4235 Typ : constant Entity_Id := Etype (N);
4236 Indexes : constant List_Id := New_List;
4241 -- If the aggregate is purely positional, all its subaggregates
4242 -- have the same size. We collect the dimensions from the first
4243 -- subaggregate at each level.
4248 for D in 1 .. Number_Dimensions (Typ) loop
4249 Sub_Agg := First (Expressions (Sub_Agg));
4253 while Present (Comp) loop
4260 Low_Bound => Make_Integer_Literal (Loc, 1),
4261 High_Bound => Make_Integer_Literal (Loc, Num)));
4265 -- We know the aggregate type is unconstrained and the aggregate
4266 -- is not processable by the back end, therefore not necessarily
4267 -- positional. Retrieve each dimension bounds (computed earlier).
4269 for D in 1 .. Number_Dimensions (Typ) loop
4272 Low_Bound => Aggr_Low (D),
4273 High_Bound => Aggr_High (D)),
4279 Make_Full_Type_Declaration (Loc,
4280 Defining_Identifier => Agg_Type,
4282 Make_Constrained_Array_Definition (Loc,
4283 Discrete_Subtype_Definitions => Indexes,
4284 Component_Definition =>
4285 Make_Component_Definition (Loc,
4286 Aliased_Present => False,
4287 Subtype_Indication =>
4288 New_Occurrence_Of (Component_Type (Typ), Loc))));
4290 Insert_Action (N, Decl);
4292 Set_Etype (N, Agg_Type);
4293 Set_Is_Itype (Agg_Type);
4294 Freeze_Itype (Agg_Type, N);
4295 end Build_Constrained_Type;
4301 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id) is
4308 Cond : Node_Id := Empty;
4311 Get_Index_Bounds (Aggr_Bounds, Aggr_Lo, Aggr_Hi);
4312 Get_Index_Bounds (Index_Bounds, Ind_Lo, Ind_Hi);
4314 -- Generate the following test:
4316 -- [constraint_error when
4317 -- Aggr_Lo <= Aggr_Hi and then
4318 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
4320 -- As an optimization try to see if some tests are trivially vacuous
4321 -- because we are comparing an expression against itself.
4323 if Aggr_Lo = Ind_Lo and then Aggr_Hi = Ind_Hi then
4326 elsif Aggr_Hi = Ind_Hi then
4329 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4330 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo));
4332 elsif Aggr_Lo = Ind_Lo then
4335 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
4336 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Hi));
4343 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4344 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo)),
4348 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
4349 Right_Opnd => Duplicate_Subexpr (Ind_Hi)));
4352 if Present (Cond) then
4357 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4358 Right_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi)),
4360 Right_Opnd => Cond);
4362 Set_Analyzed (Left_Opnd (Left_Opnd (Cond)), False);
4363 Set_Analyzed (Right_Opnd (Left_Opnd (Cond)), False);
4365 Make_Raise_Constraint_Error (Loc,
4367 Reason => CE_Length_Check_Failed));
4371 ----------------------------
4372 -- Check_Same_Aggr_Bounds --
4373 ----------------------------
4375 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos) is
4376 Sub_Lo : constant Node_Id := Low_Bound (Aggregate_Bounds (Sub_Aggr));
4377 Sub_Hi : constant Node_Id := High_Bound (Aggregate_Bounds (Sub_Aggr));
4378 -- The bounds of this specific sub-aggregate
4380 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
4381 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
4382 -- The bounds of the aggregate for this dimension
4384 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
4385 -- The index type for this dimension.xxx
4387 Cond : Node_Id := Empty;
4392 -- If index checks are on generate the test
4394 -- [constraint_error when
4395 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
4397 -- As an optimization try to see if some tests are trivially vacuos
4398 -- because we are comparing an expression against itself. Also for
4399 -- the first dimension the test is trivially vacuous because there
4400 -- is just one aggregate for dimension 1.
4402 if Index_Checks_Suppressed (Ind_Typ) then
4406 or else (Aggr_Lo = Sub_Lo and then Aggr_Hi = Sub_Hi)
4410 elsif Aggr_Hi = Sub_Hi then
4413 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4414 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo));
4416 elsif Aggr_Lo = Sub_Lo then
4419 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
4420 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Hi));
4427 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
4428 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo)),
4432 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
4433 Right_Opnd => Duplicate_Subexpr (Sub_Hi)));
4436 if Present (Cond) then
4438 Make_Raise_Constraint_Error (Loc,
4440 Reason => CE_Length_Check_Failed));
4443 -- Now look inside the sub-aggregate to see if there is more work
4445 if Dim < Aggr_Dimension then
4447 -- Process positional components
4449 if Present (Expressions (Sub_Aggr)) then
4450 Expr := First (Expressions (Sub_Aggr));
4451 while Present (Expr) loop
4452 Check_Same_Aggr_Bounds (Expr, Dim + 1);
4457 -- Process component associations
4459 if Present (Component_Associations (Sub_Aggr)) then
4460 Assoc := First (Component_Associations (Sub_Aggr));
4461 while Present (Assoc) loop
4462 Expr := Expression (Assoc);
4463 Check_Same_Aggr_Bounds (Expr, Dim + 1);
4468 end Check_Same_Aggr_Bounds;
4470 ----------------------------
4471 -- Compute_Others_Present --
4472 ----------------------------
4474 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos) is
4479 if Present (Component_Associations (Sub_Aggr)) then
4480 Assoc := Last (Component_Associations (Sub_Aggr));
4482 if Nkind (First (Choices (Assoc))) = N_Others_Choice then
4483 Others_Present (Dim) := True;
4487 -- Now look inside the sub-aggregate to see if there is more work
4489 if Dim < Aggr_Dimension then
4491 -- Process positional components
4493 if Present (Expressions (Sub_Aggr)) then
4494 Expr := First (Expressions (Sub_Aggr));
4495 while Present (Expr) loop
4496 Compute_Others_Present (Expr, Dim + 1);
4501 -- Process component associations
4503 if Present (Component_Associations (Sub_Aggr)) then
4504 Assoc := First (Component_Associations (Sub_Aggr));
4505 while Present (Assoc) loop
4506 Expr := Expression (Assoc);
4507 Compute_Others_Present (Expr, Dim + 1);
4512 end Compute_Others_Present;
4514 ------------------------
4515 -- In_Place_Assign_OK --
4516 ------------------------
4518 function In_Place_Assign_OK return Boolean is
4526 function Safe_Aggregate (Aggr : Node_Id) return Boolean;
4527 -- Check recursively that each component of a (sub)aggregate does
4528 -- not depend on the variable being assigned to.
4530 function Safe_Component (Expr : Node_Id) return Boolean;
4531 -- Verify that an expression cannot depend on the variable being
4532 -- assigned to. Room for improvement here (but less than before).
4534 --------------------
4535 -- Safe_Aggregate --
4536 --------------------
4538 function Safe_Aggregate (Aggr : Node_Id) return Boolean is
4542 if Present (Expressions (Aggr)) then
4543 Expr := First (Expressions (Aggr));
4544 while Present (Expr) loop
4545 if Nkind (Expr) = N_Aggregate then
4546 if not Safe_Aggregate (Expr) then
4550 elsif not Safe_Component (Expr) then
4558 if Present (Component_Associations (Aggr)) then
4559 Expr := First (Component_Associations (Aggr));
4560 while Present (Expr) loop
4561 if Nkind (Expression (Expr)) = N_Aggregate then
4562 if not Safe_Aggregate (Expression (Expr)) then
4566 elsif not Safe_Component (Expression (Expr)) then
4577 --------------------
4578 -- Safe_Component --
4579 --------------------
4581 function Safe_Component (Expr : Node_Id) return Boolean is
4582 Comp : Node_Id := Expr;
4584 function Check_Component (Comp : Node_Id) return Boolean;
4585 -- Do the recursive traversal, after copy
4587 ---------------------
4588 -- Check_Component --
4589 ---------------------
4591 function Check_Component (Comp : Node_Id) return Boolean is
4593 if Is_Overloaded (Comp) then
4597 return Compile_Time_Known_Value (Comp)
4599 or else (Is_Entity_Name (Comp)
4600 and then Present (Entity (Comp))
4601 and then No (Renamed_Object (Entity (Comp))))
4603 or else (Nkind (Comp) = N_Attribute_Reference
4604 and then Check_Component (Prefix (Comp)))
4606 or else (Nkind (Comp) in N_Binary_Op
4607 and then Check_Component (Left_Opnd (Comp))
4608 and then Check_Component (Right_Opnd (Comp)))
4610 or else (Nkind (Comp) in N_Unary_Op
4611 and then Check_Component (Right_Opnd (Comp)))
4613 or else (Nkind (Comp) = N_Selected_Component
4614 and then Check_Component (Prefix (Comp)))
4616 or else (Nkind (Comp) = N_Unchecked_Type_Conversion
4617 and then Check_Component (Expression (Comp)));
4618 end Check_Component;
4620 -- Start of processing for Safe_Component
4623 -- If the component appears in an association that may
4624 -- correspond to more than one element, it is not analyzed
4625 -- before the expansion into assignments, to avoid side effects.
4626 -- We analyze, but do not resolve the copy, to obtain sufficient
4627 -- entity information for the checks that follow. If component is
4628 -- overloaded we assume an unsafe function call.
4630 if not Analyzed (Comp) then
4631 if Is_Overloaded (Expr) then
4634 elsif Nkind (Expr) = N_Aggregate
4635 and then not Is_Others_Aggregate (Expr)
4639 elsif Nkind (Expr) = N_Allocator then
4641 -- For now, too complex to analyze
4646 Comp := New_Copy_Tree (Expr);
4647 Set_Parent (Comp, Parent (Expr));
4651 if Nkind (Comp) = N_Aggregate then
4652 return Safe_Aggregate (Comp);
4654 return Check_Component (Comp);
4658 -- Start of processing for In_Place_Assign_OK
4661 if Present (Component_Associations (N)) then
4663 -- On assignment, sliding can take place, so we cannot do the
4664 -- assignment in place unless the bounds of the aggregate are
4665 -- statically equal to those of the target.
4667 -- If the aggregate is given by an others choice, the bounds
4668 -- are derived from the left-hand side, and the assignment is
4669 -- safe if the expression is.
4671 if Is_Others_Aggregate (N) then
4674 (Expression (First (Component_Associations (N))));
4677 Aggr_In := First_Index (Etype (N));
4679 if Nkind (Parent (N)) = N_Assignment_Statement then
4680 Obj_In := First_Index (Etype (Name (Parent (N))));
4683 -- Context is an allocator. Check bounds of aggregate
4684 -- against given type in qualified expression.
4686 pragma Assert (Nkind (Parent (Parent (N))) = N_Allocator);
4688 First_Index (Etype (Entity (Subtype_Mark (Parent (N)))));
4691 while Present (Aggr_In) loop
4692 Get_Index_Bounds (Aggr_In, Aggr_Lo, Aggr_Hi);
4693 Get_Index_Bounds (Obj_In, Obj_Lo, Obj_Hi);
4695 if not Compile_Time_Known_Value (Aggr_Lo)
4696 or else not Compile_Time_Known_Value (Aggr_Hi)
4697 or else not Compile_Time_Known_Value (Obj_Lo)
4698 or else not Compile_Time_Known_Value (Obj_Hi)
4699 or else Expr_Value (Aggr_Lo) /= Expr_Value (Obj_Lo)
4700 or else Expr_Value (Aggr_Hi) /= Expr_Value (Obj_Hi)
4705 Next_Index (Aggr_In);
4706 Next_Index (Obj_In);
4710 -- Now check the component values themselves
4712 return Safe_Aggregate (N);
4713 end In_Place_Assign_OK;
4719 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos) is
4720 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
4721 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
4722 -- The bounds of the aggregate for this dimension
4724 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
4725 -- The index type for this dimension
4727 Need_To_Check : Boolean := False;
4729 Choices_Lo : Node_Id := Empty;
4730 Choices_Hi : Node_Id := Empty;
4731 -- The lowest and highest discrete choices for a named sub-aggregate
4733 Nb_Choices : Int := -1;
4734 -- The number of discrete non-others choices in this sub-aggregate
4736 Nb_Elements : Uint := Uint_0;
4737 -- The number of elements in a positional aggregate
4739 Cond : Node_Id := Empty;
4746 -- Check if we have an others choice. If we do make sure that this
4747 -- sub-aggregate contains at least one element in addition to the
4750 if Range_Checks_Suppressed (Ind_Typ) then
4751 Need_To_Check := False;
4753 elsif Present (Expressions (Sub_Aggr))
4754 and then Present (Component_Associations (Sub_Aggr))
4756 Need_To_Check := True;
4758 elsif Present (Component_Associations (Sub_Aggr)) then
4759 Assoc := Last (Component_Associations (Sub_Aggr));
4761 if Nkind (First (Choices (Assoc))) /= N_Others_Choice then
4762 Need_To_Check := False;
4765 -- Count the number of discrete choices. Start with -1 because
4766 -- the others choice does not count.
4769 Assoc := First (Component_Associations (Sub_Aggr));
4770 while Present (Assoc) loop
4771 Choice := First (Choices (Assoc));
4772 while Present (Choice) loop
4773 Nb_Choices := Nb_Choices + 1;
4780 -- If there is only an others choice nothing to do
4782 Need_To_Check := (Nb_Choices > 0);
4786 Need_To_Check := False;
4789 -- If we are dealing with a positional sub-aggregate with an others
4790 -- choice then compute the number or positional elements.
4792 if Need_To_Check and then Present (Expressions (Sub_Aggr)) then
4793 Expr := First (Expressions (Sub_Aggr));
4794 Nb_Elements := Uint_0;
4795 while Present (Expr) loop
4796 Nb_Elements := Nb_Elements + 1;
4800 -- If the aggregate contains discrete choices and an others choice
4801 -- compute the smallest and largest discrete choice values.
4803 elsif Need_To_Check then
4804 Compute_Choices_Lo_And_Choices_Hi : declare
4806 Table : Case_Table_Type (1 .. Nb_Choices);
4807 -- Used to sort all the different choice values
4814 Assoc := First (Component_Associations (Sub_Aggr));
4815 while Present (Assoc) loop
4816 Choice := First (Choices (Assoc));
4817 while Present (Choice) loop
4818 if Nkind (Choice) = N_Others_Choice then
4822 Get_Index_Bounds (Choice, Low, High);
4823 Table (J).Choice_Lo := Low;
4824 Table (J).Choice_Hi := High;
4833 -- Sort the discrete choices
4835 Sort_Case_Table (Table);
4837 Choices_Lo := Table (1).Choice_Lo;
4838 Choices_Hi := Table (Nb_Choices).Choice_Hi;
4839 end Compute_Choices_Lo_And_Choices_Hi;
4842 -- If no others choice in this sub-aggregate, or the aggregate
4843 -- comprises only an others choice, nothing to do.
4845 if not Need_To_Check then
4848 -- If we are dealing with an aggregate containing an others choice
4849 -- and positional components, we generate the following test:
4851 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
4852 -- Ind_Typ'Pos (Aggr_Hi)
4854 -- raise Constraint_Error;
4857 elsif Nb_Elements > Uint_0 then
4863 Make_Attribute_Reference (Loc,
4864 Prefix => New_Reference_To (Ind_Typ, Loc),
4865 Attribute_Name => Name_Pos,
4868 (Duplicate_Subexpr_Move_Checks (Aggr_Lo))),
4869 Right_Opnd => Make_Integer_Literal (Loc, Nb_Elements - 1)),
4872 Make_Attribute_Reference (Loc,
4873 Prefix => New_Reference_To (Ind_Typ, Loc),
4874 Attribute_Name => Name_Pos,
4875 Expressions => New_List (
4876 Duplicate_Subexpr_Move_Checks (Aggr_Hi))));
4878 -- If we are dealing with an aggregate containing an others choice
4879 -- and discrete choices we generate the following test:
4881 -- [constraint_error when
4882 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
4890 Duplicate_Subexpr_Move_Checks (Choices_Lo),
4892 Duplicate_Subexpr_Move_Checks (Aggr_Lo)),
4897 Duplicate_Subexpr (Choices_Hi),
4899 Duplicate_Subexpr (Aggr_Hi)));
4902 if Present (Cond) then
4904 Make_Raise_Constraint_Error (Loc,
4906 Reason => CE_Length_Check_Failed));
4907 -- Questionable reason code, shouldn't that be a
4908 -- CE_Range_Check_Failed ???
4911 -- Now look inside the sub-aggregate to see if there is more work
4913 if Dim < Aggr_Dimension then
4915 -- Process positional components
4917 if Present (Expressions (Sub_Aggr)) then
4918 Expr := First (Expressions (Sub_Aggr));
4919 while Present (Expr) loop
4920 Others_Check (Expr, Dim + 1);
4925 -- Process component associations
4927 if Present (Component_Associations (Sub_Aggr)) then
4928 Assoc := First (Component_Associations (Sub_Aggr));
4929 while Present (Assoc) loop
4930 Expr := Expression (Assoc);
4931 Others_Check (Expr, Dim + 1);
4938 -------------------------
4939 -- Safe_Left_Hand_Side --
4940 -------------------------
4942 function Safe_Left_Hand_Side (N : Node_Id) return Boolean is
4943 function Is_Safe_Index (Indx : Node_Id) return Boolean;
4944 -- If the left-hand side includes an indexed component, check that
4945 -- the indexes are free of side-effect.
4951 function Is_Safe_Index (Indx : Node_Id) return Boolean is
4953 if Is_Entity_Name (Indx) then
4956 elsif Nkind (Indx) = N_Integer_Literal then
4959 elsif Nkind (Indx) = N_Function_Call
4960 and then Is_Entity_Name (Name (Indx))
4962 Has_Pragma_Pure_Function (Entity (Name (Indx)))
4966 elsif Nkind (Indx) = N_Type_Conversion
4967 and then Is_Safe_Index (Expression (Indx))
4976 -- Start of processing for Safe_Left_Hand_Side
4979 if Is_Entity_Name (N) then
4982 elsif Nkind_In (N, N_Explicit_Dereference, N_Selected_Component)
4983 and then Safe_Left_Hand_Side (Prefix (N))
4987 elsif Nkind (N) = N_Indexed_Component
4988 and then Safe_Left_Hand_Side (Prefix (N))
4990 Is_Safe_Index (First (Expressions (N)))
4994 elsif Nkind (N) = N_Unchecked_Type_Conversion then
4995 return Safe_Left_Hand_Side (Expression (N));
5000 end Safe_Left_Hand_Side;
5005 -- Holds the temporary aggregate value
5008 -- Holds the declaration of Tmp
5010 Aggr_Code : List_Id;
5011 Parent_Node : Node_Id;
5012 Parent_Kind : Node_Kind;
5014 -- Start of processing for Expand_Array_Aggregate
5017 -- Do not touch the special aggregates of attributes used for Asm calls
5019 if Is_RTE (Ctyp, RE_Asm_Input_Operand)
5020 or else Is_RTE (Ctyp, RE_Asm_Output_Operand)
5025 -- If the semantic analyzer has determined that aggregate N will raise
5026 -- Constraint_Error at run time, then the aggregate node has been
5027 -- replaced with an N_Raise_Constraint_Error node and we should
5030 pragma Assert (not Raises_Constraint_Error (N));
5034 -- Check that the index range defined by aggregate bounds is
5035 -- compatible with corresponding index subtype.
5037 Index_Compatibility_Check : declare
5038 Aggr_Index_Range : Node_Id := First_Index (Typ);
5039 -- The current aggregate index range
5041 Index_Constraint : Node_Id := First_Index (Etype (Typ));
5042 -- The corresponding index constraint against which we have to
5043 -- check the above aggregate index range.
5046 Compute_Others_Present (N, 1);
5048 for J in 1 .. Aggr_Dimension loop
5049 -- There is no need to emit a check if an others choice is
5050 -- present for this array aggregate dimension since in this
5051 -- case one of N's sub-aggregates has taken its bounds from the
5052 -- context and these bounds must have been checked already. In
5053 -- addition all sub-aggregates corresponding to the same
5054 -- dimension must all have the same bounds (checked in (c) below).
5056 if not Range_Checks_Suppressed (Etype (Index_Constraint))
5057 and then not Others_Present (J)
5059 -- We don't use Checks.Apply_Range_Check here because it emits
5060 -- a spurious check. Namely it checks that the range defined by
5061 -- the aggregate bounds is non empty. But we know this already
5064 Check_Bounds (Aggr_Index_Range, Index_Constraint);
5067 -- Save the low and high bounds of the aggregate index as well as
5068 -- the index type for later use in checks (b) and (c) below.
5070 Aggr_Low (J) := Low_Bound (Aggr_Index_Range);
5071 Aggr_High (J) := High_Bound (Aggr_Index_Range);
5073 Aggr_Index_Typ (J) := Etype (Index_Constraint);
5075 Next_Index (Aggr_Index_Range);
5076 Next_Index (Index_Constraint);
5078 end Index_Compatibility_Check;
5082 -- If an others choice is present check that no aggregate index is
5083 -- outside the bounds of the index constraint.
5085 Others_Check (N, 1);
5089 -- For multidimensional arrays make sure that all subaggregates
5090 -- corresponding to the same dimension have the same bounds.
5092 if Aggr_Dimension > 1 then
5093 Check_Same_Aggr_Bounds (N, 1);
5098 -- Here we test for is packed array aggregate that we can handle at
5099 -- compile time. If so, return with transformation done. Note that we do
5100 -- this even if the aggregate is nested, because once we have done this
5101 -- processing, there is no more nested aggregate!
5103 if Packed_Array_Aggregate_Handled (N) then
5107 -- At this point we try to convert to positional form
5109 if Ekind (Current_Scope) = E_Package
5110 and then Static_Elaboration_Desired (Current_Scope)
5112 Convert_To_Positional (N, Max_Others_Replicate => 100);
5115 Convert_To_Positional (N);
5118 -- if the result is no longer an aggregate (e.g. it may be a string
5119 -- literal, or a temporary which has the needed value), then we are
5120 -- done, since there is no longer a nested aggregate.
5122 if Nkind (N) /= N_Aggregate then
5125 -- We are also done if the result is an analyzed aggregate
5126 -- This case could use more comments ???
5129 and then N /= Original_Node (N)
5134 -- If all aggregate components are compile-time known and the aggregate
5135 -- has been flattened, nothing left to do. The same occurs if the
5136 -- aggregate is used to initialize the components of an statically
5137 -- allocated dispatch table.
5139 if Compile_Time_Known_Aggregate (N)
5140 or else Is_Static_Dispatch_Table_Aggregate (N)
5142 Set_Expansion_Delayed (N, False);
5146 -- Now see if back end processing is possible
5148 if Backend_Processing_Possible (N) then
5150 -- If the aggregate is static but the constraints are not, build
5151 -- a static subtype for the aggregate, so that Gigi can place it
5152 -- in static memory. Perform an unchecked_conversion to the non-
5153 -- static type imposed by the context.
5156 Itype : constant Entity_Id := Etype (N);
5158 Needs_Type : Boolean := False;
5161 Index := First_Index (Itype);
5162 while Present (Index) loop
5163 if not Is_Static_Subtype (Etype (Index)) then
5172 Build_Constrained_Type (Positional => True);
5173 Rewrite (N, Unchecked_Convert_To (Itype, N));
5183 -- Delay expansion for nested aggregates: it will be taken care of
5184 -- when the parent aggregate is expanded.
5186 Parent_Node := Parent (N);
5187 Parent_Kind := Nkind (Parent_Node);
5189 if Parent_Kind = N_Qualified_Expression then
5190 Parent_Node := Parent (Parent_Node);
5191 Parent_Kind := Nkind (Parent_Node);
5194 if Parent_Kind = N_Aggregate
5195 or else Parent_Kind = N_Extension_Aggregate
5196 or else Parent_Kind = N_Component_Association
5197 or else (Parent_Kind = N_Object_Declaration
5198 and then Needs_Finalization (Typ))
5199 or else (Parent_Kind = N_Assignment_Statement
5200 and then Inside_Init_Proc)
5202 if Static_Array_Aggregate (N)
5203 or else Compile_Time_Known_Aggregate (N)
5205 Set_Expansion_Delayed (N, False);
5208 Set_Expansion_Delayed (N);
5215 -- Look if in place aggregate expansion is possible
5217 -- For object declarations we build the aggregate in place, unless
5218 -- the array is bit-packed or the component is controlled.
5220 -- For assignments we do the assignment in place if all the component
5221 -- associations have compile-time known values. For other cases we
5222 -- create a temporary. The analysis for safety of on-line assignment
5223 -- is delicate, i.e. we don't know how to do it fully yet ???
5225 -- For allocators we assign to the designated object in place if the
5226 -- aggregate meets the same conditions as other in-place assignments.
5227 -- In this case the aggregate may not come from source but was created
5228 -- for default initialization, e.g. with Initialize_Scalars.
5230 if Requires_Transient_Scope (Typ) then
5231 Establish_Transient_Scope
5232 (N, Sec_Stack => Has_Controlled_Component (Typ));
5235 if Has_Default_Init_Comps (N) then
5236 Maybe_In_Place_OK := False;
5238 elsif Is_Bit_Packed_Array (Typ)
5239 or else Has_Controlled_Component (Typ)
5241 Maybe_In_Place_OK := False;
5244 Maybe_In_Place_OK :=
5245 (Nkind (Parent (N)) = N_Assignment_Statement
5246 and then Comes_From_Source (N)
5247 and then In_Place_Assign_OK)
5250 (Nkind (Parent (Parent (N))) = N_Allocator
5251 and then In_Place_Assign_OK);
5254 -- If this is an array of tasks, it will be expanded into build-in-place
5255 -- assignments. Build an activation chain for the tasks now.
5257 if Has_Task (Etype (N)) then
5258 Build_Activation_Chain_Entity (N);
5261 -- Should document these individual tests ???
5263 if not Has_Default_Init_Comps (N)
5264 and then Comes_From_Source (Parent (N))
5265 and then Nkind (Parent (N)) = N_Object_Declaration
5267 Must_Slide (Etype (Defining_Identifier (Parent (N))), Typ)
5268 and then N = Expression (Parent (N))
5269 and then not Is_Bit_Packed_Array (Typ)
5270 and then not Has_Controlled_Component (Typ)
5272 -- If the aggregate is the expression in an object declaration, it
5273 -- cannot be expanded in place. Lookahead in the current declarative
5274 -- part to find an address clause for the object being declared. If
5275 -- one is present, we cannot build in place. Unclear comment???
5277 and then not Has_Following_Address_Clause (Parent (N))
5279 Tmp := Defining_Identifier (Parent (N));
5280 Set_No_Initialization (Parent (N));
5281 Set_Expression (Parent (N), Empty);
5283 -- Set the type of the entity, for use in the analysis of the
5284 -- subsequent indexed assignments. If the nominal type is not
5285 -- constrained, build a subtype from the known bounds of the
5286 -- aggregate. If the declaration has a subtype mark, use it,
5287 -- otherwise use the itype of the aggregate.
5289 if not Is_Constrained (Typ) then
5290 Build_Constrained_Type (Positional => False);
5291 elsif Is_Entity_Name (Object_Definition (Parent (N)))
5292 and then Is_Constrained (Entity (Object_Definition (Parent (N))))
5294 Set_Etype (Tmp, Entity (Object_Definition (Parent (N))));
5296 Set_Size_Known_At_Compile_Time (Typ, False);
5297 Set_Etype (Tmp, Typ);
5300 elsif Maybe_In_Place_OK
5301 and then Nkind (Parent (N)) = N_Qualified_Expression
5302 and then Nkind (Parent (Parent (N))) = N_Allocator
5304 Set_Expansion_Delayed (N);
5307 -- In the remaining cases the aggregate is the RHS of an assignment
5309 elsif Maybe_In_Place_OK
5310 and then Safe_Left_Hand_Side (Name (Parent (N)))
5312 Tmp := Name (Parent (N));
5314 if Etype (Tmp) /= Etype (N) then
5315 Apply_Length_Check (N, Etype (Tmp));
5317 if Nkind (N) = N_Raise_Constraint_Error then
5319 -- Static error, nothing further to expand
5325 elsif Maybe_In_Place_OK
5326 and then Nkind (Name (Parent (N))) = N_Slice
5327 and then Safe_Slice_Assignment (N)
5329 -- Safe_Slice_Assignment rewrites assignment as a loop
5335 -- In place aggregate expansion is not possible
5338 Maybe_In_Place_OK := False;
5339 Tmp := Make_Temporary (Loc, 'A', N);
5341 Make_Object_Declaration
5343 Defining_Identifier => Tmp,
5344 Object_Definition => New_Occurrence_Of (Typ, Loc));
5345 Set_No_Initialization (Tmp_Decl, True);
5347 -- If we are within a loop, the temporary will be pushed on the
5348 -- stack at each iteration. If the aggregate is the expression for an
5349 -- allocator, it will be immediately copied to the heap and can
5350 -- be reclaimed at once. We create a transient scope around the
5351 -- aggregate for this purpose.
5353 if Ekind (Current_Scope) = E_Loop
5354 and then Nkind (Parent (Parent (N))) = N_Allocator
5356 Establish_Transient_Scope (N, False);
5359 Insert_Action (N, Tmp_Decl);
5362 -- Construct and insert the aggregate code. We can safely suppress index
5363 -- checks because this code is guaranteed not to raise CE on index
5364 -- checks. However we should *not* suppress all checks.
5370 if Nkind (Tmp) = N_Defining_Identifier then
5371 Target := New_Reference_To (Tmp, Loc);
5375 if Has_Default_Init_Comps (N) then
5377 -- Ada 2005 (AI-287): This case has not been analyzed???
5379 raise Program_Error;
5382 -- Name in assignment is explicit dereference
5384 Target := New_Copy (Tmp);
5388 Build_Array_Aggr_Code (N,
5390 Index => First_Index (Typ),
5392 Scalar_Comp => Is_Scalar_Type (Ctyp));
5395 if Comes_From_Source (Tmp) then
5396 Insert_Actions_After (Parent (N), Aggr_Code);
5399 Insert_Actions (N, Aggr_Code);
5402 -- If the aggregate has been assigned in place, remove the original
5405 if Nkind (Parent (N)) = N_Assignment_Statement
5406 and then Maybe_In_Place_OK
5408 Rewrite (Parent (N), Make_Null_Statement (Loc));
5410 elsif Nkind (Parent (N)) /= N_Object_Declaration
5411 or else Tmp /= Defining_Identifier (Parent (N))
5413 Rewrite (N, New_Occurrence_Of (Tmp, Loc));
5414 Analyze_And_Resolve (N, Typ);
5416 end Expand_Array_Aggregate;
5418 ------------------------
5419 -- Expand_N_Aggregate --
5420 ------------------------
5422 procedure Expand_N_Aggregate (N : Node_Id) is
5424 if Is_Record_Type (Etype (N)) then
5425 Expand_Record_Aggregate (N);
5427 Expand_Array_Aggregate (N);
5430 when RE_Not_Available =>
5432 end Expand_N_Aggregate;
5434 ----------------------------------
5435 -- Expand_N_Extension_Aggregate --
5436 ----------------------------------
5438 -- If the ancestor part is an expression, add a component association for
5439 -- the parent field. If the type of the ancestor part is not the direct
5440 -- parent of the expected type, build recursively the needed ancestors.
5441 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
5442 -- ration for a temporary of the expected type, followed by individual
5443 -- assignments to the given components.
5445 procedure Expand_N_Extension_Aggregate (N : Node_Id) is
5446 Loc : constant Source_Ptr := Sloc (N);
5447 A : constant Node_Id := Ancestor_Part (N);
5448 Typ : constant Entity_Id := Etype (N);
5451 -- If the ancestor is a subtype mark, an init proc must be called
5452 -- on the resulting object which thus has to be materialized in
5455 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
5456 Convert_To_Assignments (N, Typ);
5458 -- The extension aggregate is transformed into a record aggregate
5459 -- of the following form (c1 and c2 are inherited components)
5461 -- (Exp with c3 => a, c4 => b)
5462 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c3 => a, c4 => b)
5467 if Tagged_Type_Expansion then
5468 Expand_Record_Aggregate (N,
5471 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc),
5474 -- No tag is needed in the case of a VM
5477 Expand_Record_Aggregate (N, Parent_Expr => A);
5482 when RE_Not_Available =>
5484 end Expand_N_Extension_Aggregate;
5486 -----------------------------
5487 -- Expand_Record_Aggregate --
5488 -----------------------------
5490 procedure Expand_Record_Aggregate
5492 Orig_Tag : Node_Id := Empty;
5493 Parent_Expr : Node_Id := Empty)
5495 Loc : constant Source_Ptr := Sloc (N);
5496 Comps : constant List_Id := Component_Associations (N);
5497 Typ : constant Entity_Id := Etype (N);
5498 Base_Typ : constant Entity_Id := Base_Type (Typ);
5500 Static_Components : Boolean := True;
5501 -- Flag to indicate whether all components are compile-time known,
5502 -- and the aggregate can be constructed statically and handled by
5505 function Component_Not_OK_For_Backend return Boolean;
5506 -- Check for presence of component which makes it impossible for the
5507 -- backend to process the aggregate, thus requiring the use of a series
5508 -- of assignment statements. Cases checked for are a nested aggregate
5509 -- needing Late_Expansion, the presence of a tagged component which may
5510 -- need tag adjustment, and a bit unaligned component reference.
5512 -- We also force expansion into assignments if a component is of a
5513 -- mutable type (including a private type with discriminants) because
5514 -- in that case the size of the component to be copied may be smaller
5515 -- than the side of the target, and there is no simple way for gigi
5516 -- to compute the size of the object to be copied.
5518 -- NOTE: This is part of the ongoing work to define precisely the
5519 -- interface between front-end and back-end handling of aggregates.
5520 -- In general it is desirable to pass aggregates as they are to gigi,
5521 -- in order to minimize elaboration code. This is one case where the
5522 -- semantics of Ada complicate the analysis and lead to anomalies in
5523 -- the gcc back-end if the aggregate is not expanded into assignments.
5525 ----------------------------------
5526 -- Component_Not_OK_For_Backend --
5527 ----------------------------------
5529 function Component_Not_OK_For_Backend return Boolean is
5539 while Present (C) loop
5541 -- If the component has box initialization, expansion is needed
5542 -- and component is not ready for backend.
5544 if Box_Present (C) then
5548 if Nkind (Expression (C)) = N_Qualified_Expression then
5549 Expr_Q := Expression (Expression (C));
5551 Expr_Q := Expression (C);
5554 -- Return true if the aggregate has any associations for tagged
5555 -- components that may require tag adjustment.
5557 -- These are cases where the source expression may have a tag that
5558 -- could differ from the component tag (e.g., can occur for type
5559 -- conversions and formal parameters). (Tag adjustment not needed
5560 -- if VM_Target because object tags are implicit in the machine.)
5562 if Is_Tagged_Type (Etype (Expr_Q))
5563 and then (Nkind (Expr_Q) = N_Type_Conversion
5564 or else (Is_Entity_Name (Expr_Q)
5566 Ekind (Entity (Expr_Q)) in Formal_Kind))
5567 and then Tagged_Type_Expansion
5569 Static_Components := False;
5572 elsif Is_Delayed_Aggregate (Expr_Q) then
5573 Static_Components := False;
5576 elsif Possible_Bit_Aligned_Component (Expr_Q) then
5577 Static_Components := False;
5581 if Is_Scalar_Type (Etype (Expr_Q)) then
5582 if not Compile_Time_Known_Value (Expr_Q) then
5583 Static_Components := False;
5586 elsif Nkind (Expr_Q) /= N_Aggregate
5587 or else not Compile_Time_Known_Aggregate (Expr_Q)
5589 Static_Components := False;
5591 if Is_Private_Type (Etype (Expr_Q))
5592 and then Has_Discriminants (Etype (Expr_Q))
5602 end Component_Not_OK_For_Backend;
5604 -- Remaining Expand_Record_Aggregate variables
5606 Tag_Value : Node_Id;
5610 -- Start of processing for Expand_Record_Aggregate
5613 -- If the aggregate is to be assigned to an atomic variable, we
5614 -- have to prevent a piecemeal assignment even if the aggregate
5615 -- is to be expanded. We create a temporary for the aggregate, and
5616 -- assign the temporary instead, so that the back end can generate
5617 -- an atomic move for it.
5620 and then Comes_From_Source (Parent (N))
5621 and then Is_Atomic_Aggregate (N, Typ)
5625 -- No special management required for aggregates used to initialize
5626 -- statically allocated dispatch tables
5628 elsif Is_Static_Dispatch_Table_Aggregate (N) then
5632 -- Ada 2005 (AI-318-2): We need to convert to assignments if components
5633 -- are build-in-place function calls. The assignments will each turn
5634 -- into a build-in-place function call. If components are all static,
5635 -- we can pass the aggregate to the backend regardless of limitedness.
5637 -- Extension aggregates, aggregates in extended return statements, and
5638 -- aggregates for C++ imported types must be expanded.
5640 if Ada_Version >= Ada_2005 and then Is_Immutably_Limited_Type (Typ) then
5641 if not Nkind_In (Parent (N), N_Object_Declaration,
5642 N_Component_Association)
5644 Convert_To_Assignments (N, Typ);
5646 elsif Nkind (N) = N_Extension_Aggregate
5647 or else Convention (Typ) = Convention_CPP
5649 Convert_To_Assignments (N, Typ);
5651 elsif not Size_Known_At_Compile_Time (Typ)
5652 or else Component_Not_OK_For_Backend
5653 or else not Static_Components
5655 Convert_To_Assignments (N, Typ);
5658 Set_Compile_Time_Known_Aggregate (N);
5659 Set_Expansion_Delayed (N, False);
5662 -- Gigi doesn't properly handle temporaries of variable size so we
5663 -- generate it in the front-end
5665 elsif not Size_Known_At_Compile_Time (Typ)
5666 and then Tagged_Type_Expansion
5668 Convert_To_Assignments (N, Typ);
5670 -- Temporaries for controlled aggregates need to be attached to a final
5671 -- chain in order to be properly finalized, so it has to be created in
5674 elsif Is_Controlled (Typ)
5675 or else Has_Controlled_Component (Base_Type (Typ))
5677 Convert_To_Assignments (N, Typ);
5679 -- Ada 2005 (AI-287): In case of default initialized components we
5680 -- convert the aggregate into assignments.
5682 elsif Has_Default_Init_Comps (N) then
5683 Convert_To_Assignments (N, Typ);
5687 elsif Component_Not_OK_For_Backend then
5688 Convert_To_Assignments (N, Typ);
5690 -- If an ancestor is private, some components are not inherited and
5691 -- we cannot expand into a record aggregate
5693 elsif Has_Private_Ancestor (Typ) then
5694 Convert_To_Assignments (N, Typ);
5696 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
5697 -- is not able to handle the aggregate for Late_Request.
5699 elsif Is_Tagged_Type (Typ) and then Has_Discriminants (Typ) then
5700 Convert_To_Assignments (N, Typ);
5702 -- If the tagged types covers interface types we need to initialize all
5703 -- hidden components containing pointers to secondary dispatch tables.
5705 elsif Is_Tagged_Type (Typ) and then Has_Interfaces (Typ) then
5706 Convert_To_Assignments (N, Typ);
5708 -- If some components are mutable, the size of the aggregate component
5709 -- may be distinct from the default size of the type component, so
5710 -- we need to expand to insure that the back-end copies the proper
5711 -- size of the data. However, if the aggregate is the initial value of
5712 -- a constant, the target is immutable and may be built statically.
5714 elsif Has_Mutable_Components (Typ)
5716 (Nkind (Parent (N)) /= N_Object_Declaration
5717 or else not Constant_Present (Parent (N)))
5719 Convert_To_Assignments (N, Typ);
5721 -- If the type involved has any non-bit aligned components, then we are
5722 -- not sure that the back end can handle this case correctly.
5724 elsif Type_May_Have_Bit_Aligned_Components (Typ) then
5725 Convert_To_Assignments (N, Typ);
5727 -- In all other cases, build a proper aggregate handlable by gigi
5730 if Nkind (N) = N_Aggregate then
5732 -- If the aggregate is static and can be handled by the back-end,
5733 -- nothing left to do.
5735 if Static_Components then
5736 Set_Compile_Time_Known_Aggregate (N);
5737 Set_Expansion_Delayed (N, False);
5741 -- If no discriminants, nothing special to do
5743 if not Has_Discriminants (Typ) then
5746 -- Case of discriminants present
5748 elsif Is_Derived_Type (Typ) then
5750 -- For untagged types, non-stored discriminants are replaced
5751 -- with stored discriminants, which are the ones that gigi uses
5752 -- to describe the type and its components.
5754 Generate_Aggregate_For_Derived_Type : declare
5755 Constraints : constant List_Id := New_List;
5756 First_Comp : Node_Id;
5757 Discriminant : Entity_Id;
5759 Num_Disc : Int := 0;
5760 Num_Gird : Int := 0;
5762 procedure Prepend_Stored_Values (T : Entity_Id);
5763 -- Scan the list of stored discriminants of the type, and add
5764 -- their values to the aggregate being built.
5766 ---------------------------
5767 -- Prepend_Stored_Values --
5768 ---------------------------
5770 procedure Prepend_Stored_Values (T : Entity_Id) is
5772 Discriminant := First_Stored_Discriminant (T);
5773 while Present (Discriminant) loop
5775 Make_Component_Association (Loc,
5777 New_List (New_Occurrence_Of (Discriminant, Loc)),
5781 Get_Discriminant_Value (
5784 Discriminant_Constraint (Typ))));
5786 if No (First_Comp) then
5787 Prepend_To (Component_Associations (N), New_Comp);
5789 Insert_After (First_Comp, New_Comp);
5792 First_Comp := New_Comp;
5793 Next_Stored_Discriminant (Discriminant);
5795 end Prepend_Stored_Values;
5797 -- Start of processing for Generate_Aggregate_For_Derived_Type
5800 -- Remove the associations for the discriminant of derived type
5802 First_Comp := First (Component_Associations (N));
5803 while Present (First_Comp) loop
5808 (First (Choices (Comp)))) = E_Discriminant
5811 Num_Disc := Num_Disc + 1;
5815 -- Insert stored discriminant associations in the correct
5816 -- order. If there are more stored discriminants than new
5817 -- discriminants, there is at least one new discriminant that
5818 -- constrains more than one of the stored discriminants. In
5819 -- this case we need to construct a proper subtype of the
5820 -- parent type, in order to supply values to all the
5821 -- components. Otherwise there is one-one correspondence
5822 -- between the constraints and the stored discriminants.
5824 First_Comp := Empty;
5826 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
5827 while Present (Discriminant) loop
5828 Num_Gird := Num_Gird + 1;
5829 Next_Stored_Discriminant (Discriminant);
5832 -- Case of more stored discriminants than new discriminants
5834 if Num_Gird > Num_Disc then
5836 -- Create a proper subtype of the parent type, which is the
5837 -- proper implementation type for the aggregate, and convert
5838 -- it to the intended target type.
5840 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
5841 while Present (Discriminant) loop
5844 Get_Discriminant_Value (
5847 Discriminant_Constraint (Typ)));
5848 Append (New_Comp, Constraints);
5849 Next_Stored_Discriminant (Discriminant);
5853 Make_Subtype_Declaration (Loc,
5854 Defining_Identifier => Make_Temporary (Loc, 'T'),
5855 Subtype_Indication =>
5856 Make_Subtype_Indication (Loc,
5858 New_Occurrence_Of (Etype (Base_Type (Typ)), Loc),
5860 Make_Index_Or_Discriminant_Constraint
5861 (Loc, Constraints)));
5863 Insert_Action (N, Decl);
5864 Prepend_Stored_Values (Base_Type (Typ));
5866 Set_Etype (N, Defining_Identifier (Decl));
5869 Rewrite (N, Unchecked_Convert_To (Typ, N));
5872 -- Case where we do not have fewer new discriminants than
5873 -- stored discriminants, so in this case we can simply use the
5874 -- stored discriminants of the subtype.
5877 Prepend_Stored_Values (Typ);
5879 end Generate_Aggregate_For_Derived_Type;
5882 if Is_Tagged_Type (Typ) then
5884 -- The tagged case, _parent and _tag component must be created
5886 -- Reset null_present unconditionally. tagged records always have
5887 -- at least one field (the tag or the parent)
5889 Set_Null_Record_Present (N, False);
5891 -- When the current aggregate comes from the expansion of an
5892 -- extension aggregate, the parent expr is replaced by an
5893 -- aggregate formed by selected components of this expr
5895 if Present (Parent_Expr)
5896 and then Is_Empty_List (Comps)
5898 Comp := First_Component_Or_Discriminant (Typ);
5899 while Present (Comp) loop
5901 -- Skip all expander-generated components
5904 not Comes_From_Source (Original_Record_Component (Comp))
5910 Make_Selected_Component (Loc,
5912 Unchecked_Convert_To (Typ,
5913 Duplicate_Subexpr (Parent_Expr, True)),
5915 Selector_Name => New_Occurrence_Of (Comp, Loc));
5918 Make_Component_Association (Loc,
5920 New_List (New_Occurrence_Of (Comp, Loc)),
5924 Analyze_And_Resolve (New_Comp, Etype (Comp));
5927 Next_Component_Or_Discriminant (Comp);
5931 -- Compute the value for the Tag now, if the type is a root it
5932 -- will be included in the aggregate right away, otherwise it will
5933 -- be propagated to the parent aggregate
5935 if Present (Orig_Tag) then
5936 Tag_Value := Orig_Tag;
5937 elsif not Tagged_Type_Expansion then
5942 (Node (First_Elmt (Access_Disp_Table (Typ))), Loc);
5945 -- For a derived type, an aggregate for the parent is formed with
5946 -- all the inherited components.
5948 if Is_Derived_Type (Typ) then
5951 First_Comp : Node_Id;
5952 Parent_Comps : List_Id;
5953 Parent_Aggr : Node_Id;
5954 Parent_Name : Node_Id;
5957 -- Remove the inherited component association from the
5958 -- aggregate and store them in the parent aggregate
5960 First_Comp := First (Component_Associations (N));
5961 Parent_Comps := New_List;
5962 while Present (First_Comp)
5963 and then Scope (Original_Record_Component (
5964 Entity (First (Choices (First_Comp))))) /= Base_Typ
5969 Append (Comp, Parent_Comps);
5972 Parent_Aggr := Make_Aggregate (Loc,
5973 Component_Associations => Parent_Comps);
5974 Set_Etype (Parent_Aggr, Etype (Base_Type (Typ)));
5976 -- Find the _parent component
5978 Comp := First_Component (Typ);
5979 while Chars (Comp) /= Name_uParent loop
5980 Comp := Next_Component (Comp);
5983 Parent_Name := New_Occurrence_Of (Comp, Loc);
5985 -- Insert the parent aggregate
5987 Prepend_To (Component_Associations (N),
5988 Make_Component_Association (Loc,
5989 Choices => New_List (Parent_Name),
5990 Expression => Parent_Aggr));
5992 -- Expand recursively the parent propagating the right Tag
5994 Expand_Record_Aggregate (
5995 Parent_Aggr, Tag_Value, Parent_Expr);
5998 -- For a root type, the tag component is added (unless compiling
5999 -- for the VMs, where tags are implicit).
6001 elsif Tagged_Type_Expansion then
6003 Tag_Name : constant Node_Id :=
6005 (First_Tag_Component (Typ), Loc);
6006 Typ_Tag : constant Entity_Id := RTE (RE_Tag);
6007 Conv_Node : constant Node_Id :=
6008 Unchecked_Convert_To (Typ_Tag, Tag_Value);
6011 Set_Etype (Conv_Node, Typ_Tag);
6012 Prepend_To (Component_Associations (N),
6013 Make_Component_Association (Loc,
6014 Choices => New_List (Tag_Name),
6015 Expression => Conv_Node));
6021 end Expand_Record_Aggregate;
6023 ----------------------------
6024 -- Has_Default_Init_Comps --
6025 ----------------------------
6027 function Has_Default_Init_Comps (N : Node_Id) return Boolean is
6028 Comps : constant List_Id := Component_Associations (N);
6032 pragma Assert (Nkind_In (N, N_Aggregate, N_Extension_Aggregate));
6038 if Has_Self_Reference (N) then
6042 -- Check if any direct component has default initialized components
6045 while Present (C) loop
6046 if Box_Present (C) then
6053 -- Recursive call in case of aggregate expression
6056 while Present (C) loop
6057 Expr := Expression (C);
6061 Nkind_In (Expr, N_Aggregate, N_Extension_Aggregate)
6062 and then Has_Default_Init_Comps (Expr)
6071 end Has_Default_Init_Comps;
6073 --------------------------
6074 -- Is_Delayed_Aggregate --
6075 --------------------------
6077 function Is_Delayed_Aggregate (N : Node_Id) return Boolean is
6078 Node : Node_Id := N;
6079 Kind : Node_Kind := Nkind (Node);
6082 if Kind = N_Qualified_Expression then
6083 Node := Expression (Node);
6084 Kind := Nkind (Node);
6087 if Kind /= N_Aggregate and then Kind /= N_Extension_Aggregate then
6090 return Expansion_Delayed (Node);
6092 end Is_Delayed_Aggregate;
6094 ----------------------------------------
6095 -- Is_Static_Dispatch_Table_Aggregate --
6096 ----------------------------------------
6098 function Is_Static_Dispatch_Table_Aggregate (N : Node_Id) return Boolean is
6099 Typ : constant Entity_Id := Base_Type (Etype (N));
6102 return Static_Dispatch_Tables
6103 and then Tagged_Type_Expansion
6104 and then RTU_Loaded (Ada_Tags)
6106 -- Avoid circularity when rebuilding the compiler
6108 and then Cunit_Entity (Get_Source_Unit (N)) /= RTU_Entity (Ada_Tags)
6109 and then (Typ = RTE (RE_Dispatch_Table_Wrapper)
6111 Typ = RTE (RE_Address_Array)
6113 Typ = RTE (RE_Type_Specific_Data)
6115 Typ = RTE (RE_Tag_Table)
6117 (RTE_Available (RE_Interface_Data)
6118 and then Typ = RTE (RE_Interface_Data))
6120 (RTE_Available (RE_Interfaces_Array)
6121 and then Typ = RTE (RE_Interfaces_Array))
6123 (RTE_Available (RE_Interface_Data_Element)
6124 and then Typ = RTE (RE_Interface_Data_Element)));
6125 end Is_Static_Dispatch_Table_Aggregate;
6127 --------------------
6128 -- Late_Expansion --
6129 --------------------
6131 function Late_Expansion
6135 Flist : Node_Id := Empty;
6136 Obj : Entity_Id := Empty) return List_Id
6139 if Is_Record_Type (Etype (N)) then
6140 return Build_Record_Aggr_Code (N, Typ, Target, Flist, Obj);
6142 else pragma Assert (Is_Array_Type (Etype (N)));
6144 Build_Array_Aggr_Code
6146 Ctype => Component_Type (Etype (N)),
6147 Index => First_Index (Typ),
6149 Scalar_Comp => Is_Scalar_Type (Component_Type (Typ)),
6155 ----------------------------------
6156 -- Make_OK_Assignment_Statement --
6157 ----------------------------------
6159 function Make_OK_Assignment_Statement
6162 Expression : Node_Id) return Node_Id
6165 Set_Assignment_OK (Name);
6167 return Make_Assignment_Statement (Sloc, Name, Expression);
6168 end Make_OK_Assignment_Statement;
6170 -----------------------
6171 -- Number_Of_Choices --
6172 -----------------------
6174 function Number_Of_Choices (N : Node_Id) return Nat is
6178 Nb_Choices : Nat := 0;
6181 if Present (Expressions (N)) then
6185 Assoc := First (Component_Associations (N));
6186 while Present (Assoc) loop
6187 Choice := First (Choices (Assoc));
6188 while Present (Choice) loop
6189 if Nkind (Choice) /= N_Others_Choice then
6190 Nb_Choices := Nb_Choices + 1;
6200 end Number_Of_Choices;
6202 ------------------------------------
6203 -- Packed_Array_Aggregate_Handled --
6204 ------------------------------------
6206 -- The current version of this procedure will handle at compile time
6207 -- any array aggregate that meets these conditions:
6209 -- One dimensional, bit packed
6210 -- Underlying packed type is modular type
6211 -- Bounds are within 32-bit Int range
6212 -- All bounds and values are static
6214 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean is
6215 Loc : constant Source_Ptr := Sloc (N);
6216 Typ : constant Entity_Id := Etype (N);
6217 Ctyp : constant Entity_Id := Component_Type (Typ);
6219 Not_Handled : exception;
6220 -- Exception raised if this aggregate cannot be handled
6223 -- For now, handle only one dimensional bit packed arrays
6225 if not Is_Bit_Packed_Array (Typ)
6226 or else Number_Dimensions (Typ) > 1
6227 or else not Is_Modular_Integer_Type (Packed_Array_Type (Typ))
6232 if not Is_Scalar_Type (Component_Type (Typ))
6233 and then Has_Non_Standard_Rep (Component_Type (Typ))
6239 Csiz : constant Nat := UI_To_Int (Component_Size (Typ));
6243 -- Bounds of index type
6247 -- Values of bounds if compile time known
6249 function Get_Component_Val (N : Node_Id) return Uint;
6250 -- Given a expression value N of the component type Ctyp, returns a
6251 -- value of Csiz (component size) bits representing this value. If
6252 -- the value is non-static or any other reason exists why the value
6253 -- cannot be returned, then Not_Handled is raised.
6255 -----------------------
6256 -- Get_Component_Val --
6257 -----------------------
6259 function Get_Component_Val (N : Node_Id) return Uint is
6263 -- We have to analyze the expression here before doing any further
6264 -- processing here. The analysis of such expressions is deferred
6265 -- till expansion to prevent some problems of premature analysis.
6267 Analyze_And_Resolve (N, Ctyp);
6269 -- Must have a compile time value. String literals have to be
6270 -- converted into temporaries as well, because they cannot easily
6271 -- be converted into their bit representation.
6273 if not Compile_Time_Known_Value (N)
6274 or else Nkind (N) = N_String_Literal
6279 Val := Expr_Rep_Value (N);
6281 -- Adjust for bias, and strip proper number of bits
6283 if Has_Biased_Representation (Ctyp) then
6284 Val := Val - Expr_Value (Type_Low_Bound (Ctyp));
6287 return Val mod Uint_2 ** Csiz;
6288 end Get_Component_Val;
6290 -- Here we know we have a one dimensional bit packed array
6293 Get_Index_Bounds (First_Index (Typ), Lo, Hi);
6295 -- Cannot do anything if bounds are dynamic
6297 if not Compile_Time_Known_Value (Lo)
6299 not Compile_Time_Known_Value (Hi)
6304 -- Or are silly out of range of int bounds
6306 Lob := Expr_Value (Lo);
6307 Hib := Expr_Value (Hi);
6309 if not UI_Is_In_Int_Range (Lob)
6311 not UI_Is_In_Int_Range (Hib)
6316 -- At this stage we have a suitable aggregate for handling at compile
6317 -- time (the only remaining checks are that the values of expressions
6318 -- in the aggregate are compile time known (check is performed by
6319 -- Get_Component_Val), and that any subtypes or ranges are statically
6322 -- If the aggregate is not fully positional at this stage, then
6323 -- convert it to positional form. Either this will fail, in which
6324 -- case we can do nothing, or it will succeed, in which case we have
6325 -- succeeded in handling the aggregate, or it will stay an aggregate,
6326 -- in which case we have failed to handle this case.
6328 if Present (Component_Associations (N)) then
6329 Convert_To_Positional
6330 (N, Max_Others_Replicate => 64, Handle_Bit_Packed => True);
6331 return Nkind (N) /= N_Aggregate;
6334 -- Otherwise we are all positional, so convert to proper value
6337 Lov : constant Int := UI_To_Int (Lob);
6338 Hiv : constant Int := UI_To_Int (Hib);
6340 Len : constant Nat := Int'Max (0, Hiv - Lov + 1);
6341 -- The length of the array (number of elements)
6343 Aggregate_Val : Uint;
6344 -- Value of aggregate. The value is set in the low order bits of
6345 -- this value. For the little-endian case, the values are stored
6346 -- from low-order to high-order and for the big-endian case the
6347 -- values are stored from high-order to low-order. Note that gigi
6348 -- will take care of the conversions to left justify the value in
6349 -- the big endian case (because of left justified modular type
6350 -- processing), so we do not have to worry about that here.
6353 -- Integer literal for resulting constructed value
6356 -- Shift count from low order for next value
6359 -- Shift increment for loop
6362 -- Next expression from positional parameters of aggregate
6365 -- For little endian, we fill up the low order bits of the target
6366 -- value. For big endian we fill up the high order bits of the
6367 -- target value (which is a left justified modular value).
6369 if Bytes_Big_Endian xor Debug_Flag_8 then
6370 Shift := Csiz * (Len - 1);
6377 -- Loop to set the values
6380 Aggregate_Val := Uint_0;
6382 Expr := First (Expressions (N));
6383 Aggregate_Val := Get_Component_Val (Expr) * Uint_2 ** Shift;
6385 for J in 2 .. Len loop
6386 Shift := Shift + Incr;
6389 Aggregate_Val + Get_Component_Val (Expr) * Uint_2 ** Shift;
6393 -- Now we can rewrite with the proper value
6396 Make_Integer_Literal (Loc,
6397 Intval => Aggregate_Val);
6398 Set_Print_In_Hex (Lit);
6400 -- Construct the expression using this literal. Note that it is
6401 -- important to qualify the literal with its proper modular type
6402 -- since universal integer does not have the required range and
6403 -- also this is a left justified modular type, which is important
6404 -- in the big-endian case.
6407 Unchecked_Convert_To (Typ,
6408 Make_Qualified_Expression (Loc,
6410 New_Occurrence_Of (Packed_Array_Type (Typ), Loc),
6411 Expression => Lit)));
6413 Analyze_And_Resolve (N, Typ);
6421 end Packed_Array_Aggregate_Handled;
6423 ----------------------------
6424 -- Has_Mutable_Components --
6425 ----------------------------
6427 function Has_Mutable_Components (Typ : Entity_Id) return Boolean is
6431 Comp := First_Component (Typ);
6432 while Present (Comp) loop
6433 if Is_Record_Type (Etype (Comp))
6434 and then Has_Discriminants (Etype (Comp))
6435 and then not Is_Constrained (Etype (Comp))
6440 Next_Component (Comp);
6444 end Has_Mutable_Components;
6446 ------------------------------
6447 -- Initialize_Discriminants --
6448 ------------------------------
6450 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id) is
6451 Loc : constant Source_Ptr := Sloc (N);
6452 Bas : constant Entity_Id := Base_Type (Typ);
6453 Par : constant Entity_Id := Etype (Bas);
6454 Decl : constant Node_Id := Parent (Par);
6458 if Is_Tagged_Type (Bas)
6459 and then Is_Derived_Type (Bas)
6460 and then Has_Discriminants (Par)
6461 and then Has_Discriminants (Bas)
6462 and then Number_Discriminants (Bas) /= Number_Discriminants (Par)
6463 and then Nkind (Decl) = N_Full_Type_Declaration
6464 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
6466 (Variant_Part (Component_List (Type_Definition (Decl))))
6467 and then Nkind (N) /= N_Extension_Aggregate
6470 -- Call init proc to set discriminants.
6471 -- There should eventually be a special procedure for this ???
6473 Ref := New_Reference_To (Defining_Identifier (N), Loc);
6474 Insert_Actions_After (N,
6475 Build_Initialization_Call (Sloc (N), Ref, Typ));
6477 end Initialize_Discriminants;
6484 (Obj_Type : Entity_Id;
6485 Typ : Entity_Id) return Boolean
6487 L1, L2, H1, H2 : Node_Id;
6489 -- No sliding if the type of the object is not established yet, if it is
6490 -- an unconstrained type whose actual subtype comes from the aggregate,
6491 -- or if the two types are identical.
6493 if not Is_Array_Type (Obj_Type) then
6496 elsif not Is_Constrained (Obj_Type) then
6499 elsif Typ = Obj_Type then
6503 -- Sliding can only occur along the first dimension
6505 Get_Index_Bounds (First_Index (Typ), L1, H1);
6506 Get_Index_Bounds (First_Index (Obj_Type), L2, H2);
6508 if not Is_Static_Expression (L1)
6509 or else not Is_Static_Expression (L2)
6510 or else not Is_Static_Expression (H1)
6511 or else not Is_Static_Expression (H2)
6515 return Expr_Value (L1) /= Expr_Value (L2)
6516 or else Expr_Value (H1) /= Expr_Value (H2);
6521 ---------------------------
6522 -- Safe_Slice_Assignment --
6523 ---------------------------
6525 function Safe_Slice_Assignment (N : Node_Id) return Boolean is
6526 Loc : constant Source_Ptr := Sloc (Parent (N));
6527 Pref : constant Node_Id := Prefix (Name (Parent (N)));
6528 Range_Node : constant Node_Id := Discrete_Range (Name (Parent (N)));
6536 -- Generate: for J in Range loop Pref (J) := Expr; end loop;
6538 if Comes_From_Source (N)
6539 and then No (Expressions (N))
6540 and then Nkind (First (Choices (First (Component_Associations (N)))))
6543 Expr := Expression (First (Component_Associations (N)));
6544 L_J := Make_Temporary (Loc, 'J');
6547 Make_Iteration_Scheme (Loc,
6548 Loop_Parameter_Specification =>
6549 Make_Loop_Parameter_Specification
6551 Defining_Identifier => L_J,
6552 Discrete_Subtype_Definition => Relocate_Node (Range_Node)));
6555 Make_Assignment_Statement (Loc,
6557 Make_Indexed_Component (Loc,
6558 Prefix => Relocate_Node (Pref),
6559 Expressions => New_List (New_Occurrence_Of (L_J, Loc))),
6560 Expression => Relocate_Node (Expr));
6562 -- Construct the final loop
6565 Make_Implicit_Loop_Statement
6566 (Node => Parent (N),
6567 Identifier => Empty,
6568 Iteration_Scheme => L_Iter,
6569 Statements => New_List (L_Body));
6571 -- Set type of aggregate to be type of lhs in assignment,
6572 -- to suppress redundant length checks.
6574 Set_Etype (N, Etype (Name (Parent (N))));
6576 Rewrite (Parent (N), Stat);
6577 Analyze (Parent (N));
6583 end Safe_Slice_Assignment;
6585 ---------------------
6586 -- Sort_Case_Table --
6587 ---------------------
6589 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
6590 L : constant Int := Case_Table'First;
6591 U : constant Int := Case_Table'Last;
6599 T := Case_Table (K + 1);
6603 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
6604 Expr_Value (T.Choice_Lo)
6606 Case_Table (J) := Case_Table (J - 1);
6610 Case_Table (J) := T;
6613 end Sort_Case_Table;
6615 ----------------------------
6616 -- Static_Array_Aggregate --
6617 ----------------------------
6619 function Static_Array_Aggregate (N : Node_Id) return Boolean is
6620 Bounds : constant Node_Id := Aggregate_Bounds (N);
6622 Typ : constant Entity_Id := Etype (N);
6623 Comp_Type : constant Entity_Id := Component_Type (Typ);
6630 if Is_Tagged_Type (Typ)
6631 or else Is_Controlled (Typ)
6632 or else Is_Packed (Typ)
6638 and then Nkind (Bounds) = N_Range
6639 and then Nkind (Low_Bound (Bounds)) = N_Integer_Literal
6640 and then Nkind (High_Bound (Bounds)) = N_Integer_Literal
6642 Lo := Low_Bound (Bounds);
6643 Hi := High_Bound (Bounds);
6645 if No (Component_Associations (N)) then
6647 -- Verify that all components are static integers
6649 Expr := First (Expressions (N));
6650 while Present (Expr) loop
6651 if Nkind (Expr) /= N_Integer_Literal then
6661 -- We allow only a single named association, either a static
6662 -- range or an others_clause, with a static expression.
6664 Expr := First (Component_Associations (N));
6666 if Present (Expressions (N)) then
6669 elsif Present (Next (Expr)) then
6672 elsif Present (Next (First (Choices (Expr)))) then
6676 -- The aggregate is static if all components are literals,
6677 -- or else all its components are static aggregates for the
6678 -- component type. We also limit the size of a static aggregate
6679 -- to prevent runaway static expressions.
6681 if Is_Array_Type (Comp_Type)
6682 or else Is_Record_Type (Comp_Type)
6684 if Nkind (Expression (Expr)) /= N_Aggregate
6686 not Compile_Time_Known_Aggregate (Expression (Expr))
6691 elsif Nkind (Expression (Expr)) /= N_Integer_Literal then
6695 if not Aggr_Size_OK (N, Typ) then
6699 -- Create a positional aggregate with the right number of
6700 -- copies of the expression.
6702 Agg := Make_Aggregate (Sloc (N), New_List, No_List);
6704 for I in UI_To_Int (Intval (Lo)) .. UI_To_Int (Intval (Hi))
6707 (Expressions (Agg), New_Copy (Expression (Expr)));
6709 -- The copied expression must be analyzed and resolved.
6710 -- Besides setting the type, this ensures that static
6711 -- expressions are appropriately marked as such.
6714 (Last (Expressions (Agg)), Component_Type (Typ));
6717 Set_Aggregate_Bounds (Agg, Bounds);
6718 Set_Etype (Agg, Typ);
6721 Set_Compile_Time_Known_Aggregate (N);
6730 end Static_Array_Aggregate;