1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004 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 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Elists; use Elists;
32 with Expander; use Expander;
33 with Exp_Util; use Exp_Util;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch7; use Exp_Ch7;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Tss; use Exp_Tss;
38 with Freeze; use Freeze;
39 with Hostparm; use Hostparm;
40 with Itypes; use Itypes;
42 with Nmake; use Nmake;
43 with Nlists; use Nlists;
44 with Restrict; use Restrict;
45 with Rident; use Rident;
46 with Rtsfind; use Rtsfind;
47 with Ttypes; use Ttypes;
49 with Sem_Ch3; use Sem_Ch3;
50 with Sem_Eval; use Sem_Eval;
51 with Sem_Res; use Sem_Res;
52 with Sem_Util; use Sem_Util;
53 with Sinfo; use Sinfo;
54 with Snames; use Snames;
55 with Stand; use Stand;
56 with Tbuild; use Tbuild;
57 with Uintp; use Uintp;
59 package body Exp_Aggr is
61 type Case_Bounds is record
64 Choice_Node : Node_Id;
67 type Case_Table_Type is array (Nat range <>) of Case_Bounds;
68 -- Table type used by Check_Case_Choices procedure
70 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type);
71 -- Sort the Case Table using the Lower Bound of each Choice as the key.
72 -- A simple insertion sort is used since the number of choices in a case
73 -- statement of variant part will usually be small and probably in near
76 function Has_Default_Init_Comps (N : Node_Id) return Boolean;
77 -- N is an aggregate (record or array). Checks the presence of default
78 -- initialization (<>) in any component (Ada 2005: AI-287)
80 ------------------------------------------------------
81 -- Local subprograms for Record Aggregate Expansion --
82 ------------------------------------------------------
84 procedure Expand_Record_Aggregate
86 Orig_Tag : Node_Id := Empty;
87 Parent_Expr : Node_Id := Empty);
88 -- This is the top level procedure for record aggregate expansion.
89 -- Expansion for record aggregates needs expand aggregates for tagged
90 -- record types. Specifically Expand_Record_Aggregate adds the Tag
91 -- field in front of the Component_Association list that was created
92 -- during resolution by Resolve_Record_Aggregate.
94 -- N is the record aggregate node.
95 -- Orig_Tag is the value of the Tag that has to be provided for this
96 -- specific aggregate. It carries the tag corresponding to the type
97 -- of the outermost aggregate during the recursive expansion
98 -- Parent_Expr is the ancestor part of the original extension
101 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id);
102 -- N is an N_Aggregate of a N_Extension_Aggregate. Typ is the type of
103 -- the aggregate. Transform the given aggregate into a sequence of
104 -- assignments component per component.
106 function Build_Record_Aggr_Code
110 Flist : Node_Id := Empty;
111 Obj : Entity_Id := Empty;
112 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id;
113 -- N is an N_Aggregate or a N_Extension_Aggregate. Typ is the type
114 -- of the aggregate. Target is an expression containing the
115 -- location on which the component by component assignments will
116 -- take place. Returns the list of assignments plus all other
117 -- adjustments needed for tagged and controlled types. Flist is an
118 -- expression representing the finalization list on which to
119 -- attach the controlled components if any. Obj is present in the
120 -- object declaration and dynamic allocation cases, it contains
121 -- an entity that allows to know if the value being created needs to be
122 -- attached to the final list in case of pragma finalize_Storage_Only.
123 -- Is_Limited_Ancestor_Expansion indicates that the function has been
124 -- called recursively to expand the limited ancestor to avoid copying it.
126 function Has_Mutable_Components (Typ : Entity_Id) return Boolean;
127 -- Return true if one of the component is of a discriminated type with
128 -- defaults. An aggregate for a type with mutable components must be
129 -- expanded into individual assignments.
131 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id);
132 -- If the type of the aggregate is a type extension with renamed discrimi-
133 -- nants, we must initialize the hidden discriminants of the parent.
134 -- Otherwise, the target object must not be initialized. The discriminants
135 -- are initialized by calling the initialization procedure for the type.
136 -- This is incorrect if the initialization of other components has any
137 -- side effects. We restrict this call to the case where the parent type
138 -- has a variant part, because this is the only case where the hidden
139 -- discriminants are accessed, namely when calling discriminant checking
140 -- functions of the parent type, and when applying a stream attribute to
141 -- an object of the derived type.
143 -----------------------------------------------------
144 -- Local Subprograms for Array Aggregate Expansion --
145 -----------------------------------------------------
147 procedure Convert_To_Positional
149 Max_Others_Replicate : Nat := 5;
150 Handle_Bit_Packed : Boolean := False);
151 -- If possible, convert named notation to positional notation. This
152 -- conversion is possible only in some static cases. If the conversion
153 -- is possible, then N is rewritten with the analyzed converted
154 -- aggregate. The parameter Max_Others_Replicate controls the maximum
155 -- number of values corresponding to an others choice that will be
156 -- converted to positional notation (the default of 5 is the normal
157 -- limit, and reflects the fact that normally the loop is better than
158 -- a lot of separate assignments). Note that this limit gets overridden
159 -- in any case if either of the restrictions No_Elaboration_Code or
160 -- No_Implicit_Loops is set. The parameter Handle_Bit_Packed is usually
161 -- set False (since we do not expect the back end to handle bit packed
162 -- arrays, so the normal case of conversion is pointless), but in the
163 -- special case of a call from Packed_Array_Aggregate_Handled, we set
164 -- this parameter to True, since these are cases we handle in there.
166 procedure Expand_Array_Aggregate (N : Node_Id);
167 -- This is the top-level routine to perform array aggregate expansion.
168 -- N is the N_Aggregate node to be expanded.
170 function Backend_Processing_Possible (N : Node_Id) return Boolean;
171 -- This function checks if array aggregate N can be processed directly
172 -- by Gigi. If this is the case True is returned.
174 function Build_Array_Aggr_Code
179 Scalar_Comp : Boolean;
180 Indices : List_Id := No_List;
181 Flist : Node_Id := Empty) return List_Id;
182 -- This recursive routine returns a list of statements containing the
183 -- loops and assignments that are needed for the expansion of the array
186 -- N is the (sub-)aggregate node to be expanded into code. This node
187 -- has been fully analyzed, and its Etype is properly set.
189 -- Index is the index node corresponding to the array sub-aggregate N.
191 -- Into is the target expression into which we are copying the aggregate.
192 -- Note that this node may not have been analyzed yet, and so the Etype
193 -- field may not be set.
195 -- Scalar_Comp is True if the component type of the aggregate is scalar.
197 -- Indices is the current list of expressions used to index the
198 -- object we are writing into.
200 -- Flist is an expression representing the finalization list on which
201 -- to attach the controlled components if any.
203 function Number_Of_Choices (N : Node_Id) return Nat;
204 -- Returns the number of discrete choices (not including the others choice
205 -- if present) contained in (sub-)aggregate N.
207 function Late_Expansion
211 Flist : Node_Id := Empty;
212 Obj : Entity_Id := Empty) return List_Id;
213 -- N is a nested (record or array) aggregate that has been marked
214 -- with 'Delay_Expansion'. Typ is the expected type of the
215 -- aggregate and Target is a (duplicable) expression that will
216 -- hold the result of the aggregate expansion. Flist is the
217 -- finalization list to be used to attach controlled
218 -- components. 'Obj' when non empty, carries the original object
219 -- being initialized in order to know if it needs to be attached
220 -- to the previous parameter which may not be the case when
221 -- Finalize_Storage_Only is set. Basically this procedure is used
222 -- to implement top-down expansions of nested aggregates. This is
223 -- necessary for avoiding temporaries at each level as well as for
224 -- propagating the right internal finalization list.
226 function Make_OK_Assignment_Statement
229 Expression : Node_Id) return Node_Id;
230 -- This is like Make_Assignment_Statement, except that Assignment_OK
231 -- is set in the left operand. All assignments built by this unit
232 -- use this routine. This is needed to deal with assignments to
233 -- initialized constants that are done in place.
235 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean;
236 -- Given an array aggregate, this function handles the case of a packed
237 -- array aggregate with all constant values, where the aggregate can be
238 -- evaluated at compile time. If this is possible, then N is rewritten
239 -- to be its proper compile time value with all the components properly
240 -- assembled. The expression is analyzed and resolved and True is
241 -- returned. If this transformation is not possible, N is unchanged
242 -- and False is returned
244 function Safe_Slice_Assignment (N : Node_Id) return Boolean;
245 -- If a slice assignment has an aggregate with a single others_choice,
246 -- the assignment can be done in place even if bounds are not static,
247 -- by converting it into a loop over the discrete range of the slice.
249 ---------------------------------
250 -- Backend_Processing_Possible --
251 ---------------------------------
253 -- Backend processing by Gigi/gcc is possible only if all the following
254 -- conditions are met:
256 -- 1. N is fully positional
258 -- 2. N is not a bit-packed array aggregate;
260 -- 3. The size of N's array type must be known at compile time. Note
261 -- that this implies that the component size is also known
263 -- 4. The array type of N does not follow the Fortran layout convention
264 -- or if it does it must be 1 dimensional.
266 -- 5. The array component type is tagged, which may necessitate
267 -- reassignment of proper tags.
269 -- 6. The array component type might have unaligned bit components
271 function Backend_Processing_Possible (N : Node_Id) return Boolean is
272 Typ : constant Entity_Id := Etype (N);
273 -- Typ is the correct constrained array subtype of the aggregate.
275 function Static_Check (N : Node_Id; Index : Node_Id) return Boolean;
276 -- Recursively checks that N is fully positional, returns true if so.
282 function Static_Check (N : Node_Id; Index : Node_Id) return Boolean is
286 -- Check for component associations
288 if Present (Component_Associations (N)) then
292 -- Recurse to check subaggregates, which may appear in qualified
293 -- expressions. If delayed, the front-end will have to expand.
295 Expr := First (Expressions (N));
297 while Present (Expr) loop
299 if Is_Delayed_Aggregate (Expr) then
303 if Present (Next_Index (Index))
304 and then not Static_Check (Expr, Next_Index (Index))
315 -- Start of processing for Backend_Processing_Possible
318 -- Checks 2 (array must not be bit packed)
320 if Is_Bit_Packed_Array (Typ) then
324 -- Checks 4 (array must not be multi-dimensional Fortran case)
326 if Convention (Typ) = Convention_Fortran
327 and then Number_Dimensions (Typ) > 1
332 -- Checks 3 (size of array must be known at compile time)
334 if not Size_Known_At_Compile_Time (Typ) then
338 -- Checks 1 (aggregate must be fully positional)
340 if not Static_Check (N, First_Index (Typ)) then
344 -- Checks 5 (if the component type is tagged, then we may need
345 -- to do tag adjustments; perhaps this should be refined to
346 -- check for any component associations that actually
347 -- need tag adjustment, along the lines of the test that's
348 -- done in Has_Delayed_Nested_Aggregate_Or_Tagged_Comps
349 -- for record aggregates with tagged components, but not
350 -- clear whether it's worthwhile ???; in the case of the
351 -- JVM, object tags are handled implicitly)
353 if Is_Tagged_Type (Component_Type (Typ)) and then not Java_VM then
357 -- Checks 6 (component type must not have bit aligned components)
359 if Type_May_Have_Bit_Aligned_Components (Component_Type (Typ)) then
363 -- Backend processing is possible
365 Set_Compile_Time_Known_Aggregate (N, True);
366 Set_Size_Known_At_Compile_Time (Etype (N), True);
368 end Backend_Processing_Possible;
370 ---------------------------
371 -- Build_Array_Aggr_Code --
372 ---------------------------
374 -- The code that we generate from a one dimensional aggregate is
376 -- 1. If the sub-aggregate contains discrete choices we
378 -- (a) Sort the discrete choices
380 -- (b) Otherwise for each discrete choice that specifies a range we
381 -- emit a loop. If a range specifies a maximum of three values, or
382 -- we are dealing with an expression we emit a sequence of
383 -- assignments instead of a loop.
385 -- (c) Generate the remaining loops to cover the others choice if any.
387 -- 2. If the aggregate contains positional elements we
389 -- (a) translate the positional elements in a series of assignments.
391 -- (b) Generate a final loop to cover the others choice if any.
392 -- Note that this final loop has to be a while loop since the case
394 -- L : Integer := Integer'Last;
395 -- H : Integer := Integer'Last;
396 -- A : array (L .. H) := (1, others =>0);
398 -- cannot be handled by a for loop. Thus for the following
400 -- array (L .. H) := (.. positional elements.., others =>E);
402 -- we always generate something like:
404 -- J : Index_Type := Index_Of_Last_Positional_Element;
406 -- J := Index_Base'Succ (J)
410 function Build_Array_Aggr_Code
415 Scalar_Comp : Boolean;
416 Indices : List_Id := No_List;
417 Flist : Node_Id := Empty) return List_Id
419 Loc : constant Source_Ptr := Sloc (N);
420 Index_Base : constant Entity_Id := Base_Type (Etype (Index));
421 Index_Base_L : constant Node_Id := Type_Low_Bound (Index_Base);
422 Index_Base_H : constant Node_Id := Type_High_Bound (Index_Base);
424 function Add (Val : Int; To : Node_Id) return Node_Id;
425 -- Returns an expression where Val is added to expression To,
426 -- unless To+Val is provably out of To's base type range.
427 -- To must be an already analyzed expression.
429 function Empty_Range (L, H : Node_Id) return Boolean;
430 -- Returns True if the range defined by L .. H is certainly empty.
432 function Equal (L, H : Node_Id) return Boolean;
433 -- Returns True if L = H for sure.
435 function Index_Base_Name return Node_Id;
436 -- Returns a new reference to the index type name.
438 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id;
439 -- Ind must be a side-effect free expression. If the input aggregate
440 -- N to Build_Loop contains no sub-aggregates, then this function
441 -- returns the assignment statement:
443 -- Into (Indices, Ind) := Expr;
445 -- Otherwise we call Build_Code recursively.
447 -- Ada 2005 (AI-287): In case of default initialized component, Expr
448 -- is empty and we generate a call to the corresponding IP subprogram.
450 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id;
451 -- Nodes L and H must be side-effect free expressions.
452 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
453 -- This routine returns the for loop statement
455 -- for J in Index_Base'(L) .. Index_Base'(H) loop
456 -- Into (Indices, J) := Expr;
459 -- Otherwise we call Build_Code recursively.
460 -- As an optimization if the loop covers 3 or less scalar elements we
461 -- generate a sequence of assignments.
463 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id;
464 -- Nodes L and H must be side-effect free expressions.
465 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
466 -- This routine returns the while loop statement
468 -- J : Index_Base := L;
470 -- J := Index_Base'Succ (J);
471 -- Into (Indices, J) := Expr;
474 -- Otherwise we call Build_Code recursively
476 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean;
477 function Local_Expr_Value (E : Node_Id) return Uint;
478 -- These two Local routines are used to replace the corresponding ones
479 -- in sem_eval because while processing the bounds of an aggregate with
480 -- discrete choices whose index type is an enumeration, we build static
481 -- expressions not recognized by Compile_Time_Known_Value as such since
482 -- they have not yet been analyzed and resolved. All the expressions in
483 -- question are things like Index_Base_Name'Val (Const) which we can
484 -- easily recognize as being constant.
490 function Add (Val : Int; To : Node_Id) return Node_Id is
495 U_Val : constant Uint := UI_From_Int (Val);
498 -- Note: do not try to optimize the case of Val = 0, because
499 -- we need to build a new node with the proper Sloc value anyway.
501 -- First test if we can do constant folding
503 if Local_Compile_Time_Known_Value (To) then
504 U_To := Local_Expr_Value (To) + Val;
506 -- Determine if our constant is outside the range of the index.
507 -- If so return an Empty node. This empty node will be caught
508 -- by Empty_Range below.
510 if Compile_Time_Known_Value (Index_Base_L)
511 and then U_To < Expr_Value (Index_Base_L)
515 elsif Compile_Time_Known_Value (Index_Base_H)
516 and then U_To > Expr_Value (Index_Base_H)
521 Expr_Pos := Make_Integer_Literal (Loc, U_To);
522 Set_Is_Static_Expression (Expr_Pos);
524 if not Is_Enumeration_Type (Index_Base) then
527 -- If we are dealing with enumeration return
528 -- Index_Base'Val (Expr_Pos)
532 Make_Attribute_Reference
534 Prefix => Index_Base_Name,
535 Attribute_Name => Name_Val,
536 Expressions => New_List (Expr_Pos));
542 -- If we are here no constant folding possible
544 if not Is_Enumeration_Type (Index_Base) then
547 Left_Opnd => Duplicate_Subexpr (To),
548 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
550 -- If we are dealing with enumeration return
551 -- Index_Base'Val (Index_Base'Pos (To) + Val)
555 Make_Attribute_Reference
557 Prefix => Index_Base_Name,
558 Attribute_Name => Name_Pos,
559 Expressions => New_List (Duplicate_Subexpr (To)));
564 Right_Opnd => Make_Integer_Literal (Loc, U_Val));
567 Make_Attribute_Reference
569 Prefix => Index_Base_Name,
570 Attribute_Name => Name_Val,
571 Expressions => New_List (Expr_Pos));
581 function Empty_Range (L, H : Node_Id) return Boolean is
582 Is_Empty : Boolean := False;
587 -- First check if L or H were already detected as overflowing the
588 -- index base range type by function Add above. If this is so Add
589 -- returns the empty node.
591 if No (L) or else No (H) then
598 -- L > H range is empty
604 -- B_L > H range must be empty
610 -- L > B_H range must be empty
614 High := Index_Base_H;
617 if Local_Compile_Time_Known_Value (Low)
618 and then Local_Compile_Time_Known_Value (High)
621 UI_Gt (Local_Expr_Value (Low), Local_Expr_Value (High));
634 function Equal (L, H : Node_Id) return Boolean is
639 elsif Local_Compile_Time_Known_Value (L)
640 and then Local_Compile_Time_Known_Value (H)
642 return UI_Eq (Local_Expr_Value (L), Local_Expr_Value (H));
652 function Gen_Assign (Ind : Node_Id; Expr : Node_Id) return List_Id is
653 L : constant List_Id := New_List;
657 New_Indices : List_Id;
658 Indexed_Comp : Node_Id;
660 Comp_Type : Entity_Id := Empty;
662 function Add_Loop_Actions (Lis : List_Id) return List_Id;
663 -- Collect insert_actions generated in the construction of a
664 -- loop, and prepend them to the sequence of assignments to
665 -- complete the eventual body of the loop.
667 ----------------------
668 -- Add_Loop_Actions --
669 ----------------------
671 function Add_Loop_Actions (Lis : List_Id) return List_Id is
675 -- Ada 2005 (AI-287): Do nothing else in case of default
676 -- initialized component.
678 if not Present (Expr) then
681 elsif Nkind (Parent (Expr)) = N_Component_Association
682 and then Present (Loop_Actions (Parent (Expr)))
684 Append_List (Lis, Loop_Actions (Parent (Expr)));
685 Res := Loop_Actions (Parent (Expr));
686 Set_Loop_Actions (Parent (Expr), No_List);
692 end Add_Loop_Actions;
694 -- Start of processing for Gen_Assign
698 New_Indices := New_List;
700 New_Indices := New_Copy_List_Tree (Indices);
703 Append_To (New_Indices, Ind);
705 if Present (Flist) then
706 F := New_Copy_Tree (Flist);
708 elsif Present (Etype (N)) and then Controlled_Type (Etype (N)) then
709 if Is_Entity_Name (Into)
710 and then Present (Scope (Entity (Into)))
712 F := Find_Final_List (Scope (Entity (Into)));
714 F := Find_Final_List (Current_Scope);
720 if Present (Next_Index (Index)) then
723 Build_Array_Aggr_Code
726 Index => Next_Index (Index),
728 Scalar_Comp => Scalar_Comp,
729 Indices => New_Indices,
733 -- If we get here then we are at a bottom-level (sub-)aggregate
737 (Make_Indexed_Component (Loc,
738 Prefix => New_Copy_Tree (Into),
739 Expressions => New_Indices));
741 Set_Assignment_OK (Indexed_Comp);
743 -- Ada 2005 (AI-287): In case of default initialized component, Expr
744 -- is not present (and therefore we also initialize Expr_Q to empty).
746 if not Present (Expr) then
748 elsif Nkind (Expr) = N_Qualified_Expression then
749 Expr_Q := Expression (Expr);
754 if Present (Etype (N))
755 and then Etype (N) /= Any_Composite
757 Comp_Type := Component_Type (Etype (N));
758 pragma Assert (Comp_Type = Ctype); -- AI-287
760 elsif Present (Next (First (New_Indices))) then
762 -- Ada 2005 (AI-287): Do nothing in case of default initialized
763 -- component because we have received the component type in
764 -- the formal parameter Ctype.
766 -- ??? Some assert pragmas have been added to check if this new
767 -- formal can be used to replace this code in all cases.
769 if Present (Expr) then
771 -- This is a multidimensional array. Recover the component
772 -- type from the outermost aggregate, because subaggregates
773 -- do not have an assigned type.
776 P : Node_Id := Parent (Expr);
779 while Present (P) loop
780 if Nkind (P) = N_Aggregate
781 and then Present (Etype (P))
783 Comp_Type := Component_Type (Etype (P));
791 pragma Assert (Comp_Type = Ctype); -- AI-287
796 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
797 -- default initialized components (otherwise Expr_Q is not present).
800 and then (Nkind (Expr_Q) = N_Aggregate
801 or else Nkind (Expr_Q) = N_Extension_Aggregate)
803 -- At this stage the Expression may not have been
804 -- analyzed yet because the array aggregate code has not
805 -- been updated to use the Expansion_Delayed flag and
806 -- avoid analysis altogether to solve the same problem
807 -- (see Resolve_Aggr_Expr). So let us do the analysis of
808 -- non-array aggregates now in order to get the value of
809 -- Expansion_Delayed flag for the inner aggregate ???
811 if Present (Comp_Type) and then not Is_Array_Type (Comp_Type) then
812 Analyze_And_Resolve (Expr_Q, Comp_Type);
815 if Is_Delayed_Aggregate (Expr_Q) then
818 Late_Expansion (Expr_Q, Etype (Expr_Q), Indexed_Comp, F));
822 -- Ada 2005 (AI-287): In case of default initialized component, call
823 -- the initialization subprogram associated with the component type.
825 if not Present (Expr) then
827 if Present (Base_Init_Proc (Etype (Ctype)))
828 or else Has_Task (Base_Type (Ctype))
831 Build_Initialization_Call (Loc,
832 Id_Ref => Indexed_Comp,
834 With_Default_Init => True));
838 -- Now generate the assignment with no associated controlled
839 -- actions since the target of the assignment may not have
840 -- been initialized, it is not possible to Finalize it as
841 -- expected by normal controlled assignment. The rest of the
842 -- controlled actions are done manually with the proper
843 -- finalization list coming from the context.
846 Make_OK_Assignment_Statement (Loc,
847 Name => Indexed_Comp,
848 Expression => New_Copy_Tree (Expr));
850 if Present (Comp_Type) and then Controlled_Type (Comp_Type) then
851 Set_No_Ctrl_Actions (A);
856 -- Adjust the tag if tagged (because of possible view
857 -- conversions), unless compiling for the Java VM
858 -- where tags are implicit.
860 if Present (Comp_Type)
861 and then Is_Tagged_Type (Comp_Type)
865 Make_OK_Assignment_Statement (Loc,
867 Make_Selected_Component (Loc,
868 Prefix => New_Copy_Tree (Indexed_Comp),
870 New_Reference_To (Tag_Component (Comp_Type), Loc)),
873 Unchecked_Convert_To (RTE (RE_Tag),
875 Access_Disp_Table (Comp_Type), Loc)));
880 -- Adjust and Attach the component to the proper final list
881 -- which can be the controller of the outer record object or
882 -- the final list associated with the scope
884 if Present (Comp_Type) and then Controlled_Type (Comp_Type) then
887 Ref => New_Copy_Tree (Indexed_Comp),
890 With_Attach => Make_Integer_Literal (Loc, 1)));
894 return Add_Loop_Actions (L);
901 function Gen_Loop (L, H : Node_Id; Expr : Node_Id) return List_Id is
905 -- Index_Base'(L) .. Index_Base'(H)
907 L_Iteration_Scheme : Node_Id;
908 -- L_J in Index_Base'(L) .. Index_Base'(H)
911 -- The statements to execute in the loop
913 S : constant List_Id := New_List;
914 -- List of statements
917 -- Copy of expression tree, used for checking purposes
920 -- If loop bounds define an empty range return the null statement
922 if Empty_Range (L, H) then
923 Append_To (S, Make_Null_Statement (Loc));
925 -- Ada 2005 (AI-287): Nothing else need to be done in case of
926 -- default initialized component.
928 if not Present (Expr) then
932 -- The expression must be type-checked even though no component
933 -- of the aggregate will have this value. This is done only for
934 -- actual components of the array, not for subaggregates. Do
935 -- the check on a copy, because the expression may be shared
936 -- among several choices, some of which might be non-null.
938 if Present (Etype (N))
939 and then Is_Array_Type (Etype (N))
940 and then No (Next_Index (Index))
942 Expander_Mode_Save_And_Set (False);
943 Tcopy := New_Copy_Tree (Expr);
944 Set_Parent (Tcopy, N);
945 Analyze_And_Resolve (Tcopy, Component_Type (Etype (N)));
946 Expander_Mode_Restore;
952 -- If loop bounds are the same then generate an assignment
954 elsif Equal (L, H) then
955 return Gen_Assign (New_Copy_Tree (L), Expr);
957 -- If H - L <= 2 then generate a sequence of assignments
958 -- when we are processing the bottom most aggregate and it contains
959 -- scalar components.
961 elsif No (Next_Index (Index))
963 and then Local_Compile_Time_Known_Value (L)
964 and then Local_Compile_Time_Known_Value (H)
965 and then Local_Expr_Value (H) - Local_Expr_Value (L) <= 2
968 Append_List_To (S, Gen_Assign (New_Copy_Tree (L), Expr));
969 Append_List_To (S, Gen_Assign (Add (1, To => L), Expr));
971 if Local_Expr_Value (H) - Local_Expr_Value (L) = 2 then
972 Append_List_To (S, Gen_Assign (Add (2, To => L), Expr));
978 -- Otherwise construct the loop, starting with the loop index L_J
980 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
982 -- Construct "L .. H"
987 Low_Bound => Make_Qualified_Expression
989 Subtype_Mark => Index_Base_Name,
991 High_Bound => Make_Qualified_Expression
993 Subtype_Mark => Index_Base_Name,
996 -- Construct "for L_J in Index_Base range L .. H"
998 L_Iteration_Scheme :=
999 Make_Iteration_Scheme
1001 Loop_Parameter_Specification =>
1002 Make_Loop_Parameter_Specification
1004 Defining_Identifier => L_J,
1005 Discrete_Subtype_Definition => L_Range));
1007 -- Construct the statements to execute in the loop body
1009 L_Body := Gen_Assign (New_Reference_To (L_J, Loc), Expr);
1011 -- Construct the final loop
1013 Append_To (S, Make_Implicit_Loop_Statement
1015 Identifier => Empty,
1016 Iteration_Scheme => L_Iteration_Scheme,
1017 Statements => L_Body));
1026 -- The code built is
1028 -- W_J : Index_Base := L;
1029 -- while W_J < H loop
1030 -- W_J := Index_Base'Succ (W);
1034 function Gen_While (L, H : Node_Id; Expr : Node_Id) return List_Id is
1038 -- W_J : Base_Type := L;
1040 W_Iteration_Scheme : Node_Id;
1043 W_Index_Succ : Node_Id;
1044 -- Index_Base'Succ (J)
1046 W_Increment : Node_Id;
1047 -- W_J := Index_Base'Succ (W)
1049 W_Body : constant List_Id := New_List;
1050 -- The statements to execute in the loop
1052 S : constant List_Id := New_List;
1053 -- list of statement
1056 -- If loop bounds define an empty range or are equal return null
1058 if Empty_Range (L, H) or else Equal (L, H) then
1059 Append_To (S, Make_Null_Statement (Loc));
1063 -- Build the decl of W_J
1065 W_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
1067 Make_Object_Declaration
1069 Defining_Identifier => W_J,
1070 Object_Definition => Index_Base_Name,
1073 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1074 -- that in this particular case L is a fresh Expr generated by
1075 -- Add which we are the only ones to use.
1077 Append_To (S, W_Decl);
1079 -- Construct " while W_J < H"
1081 W_Iteration_Scheme :=
1082 Make_Iteration_Scheme
1084 Condition => Make_Op_Lt
1086 Left_Opnd => New_Reference_To (W_J, Loc),
1087 Right_Opnd => New_Copy_Tree (H)));
1089 -- Construct the statements to execute in the loop body
1092 Make_Attribute_Reference
1094 Prefix => Index_Base_Name,
1095 Attribute_Name => Name_Succ,
1096 Expressions => New_List (New_Reference_To (W_J, Loc)));
1099 Make_OK_Assignment_Statement
1101 Name => New_Reference_To (W_J, Loc),
1102 Expression => W_Index_Succ);
1104 Append_To (W_Body, W_Increment);
1105 Append_List_To (W_Body,
1106 Gen_Assign (New_Reference_To (W_J, Loc), Expr));
1108 -- Construct the final loop
1110 Append_To (S, Make_Implicit_Loop_Statement
1112 Identifier => Empty,
1113 Iteration_Scheme => W_Iteration_Scheme,
1114 Statements => W_Body));
1119 ---------------------
1120 -- Index_Base_Name --
1121 ---------------------
1123 function Index_Base_Name return Node_Id is
1125 return New_Reference_To (Index_Base, Sloc (N));
1126 end Index_Base_Name;
1128 ------------------------------------
1129 -- Local_Compile_Time_Known_Value --
1130 ------------------------------------
1132 function Local_Compile_Time_Known_Value (E : Node_Id) return Boolean is
1134 return Compile_Time_Known_Value (E)
1136 (Nkind (E) = N_Attribute_Reference
1137 and then Attribute_Name (E) = Name_Val
1138 and then Compile_Time_Known_Value (First (Expressions (E))));
1139 end Local_Compile_Time_Known_Value;
1141 ----------------------
1142 -- Local_Expr_Value --
1143 ----------------------
1145 function Local_Expr_Value (E : Node_Id) return Uint is
1147 if Compile_Time_Known_Value (E) then
1148 return Expr_Value (E);
1150 return Expr_Value (First (Expressions (E)));
1152 end Local_Expr_Value;
1154 -- Build_Array_Aggr_Code Variables
1161 Others_Expr : Node_Id := Empty;
1162 Others_Mbox_Present : Boolean := False;
1164 Aggr_L : constant Node_Id := Low_Bound (Aggregate_Bounds (N));
1165 Aggr_H : constant Node_Id := High_Bound (Aggregate_Bounds (N));
1166 -- The aggregate bounds of this specific sub-aggregate. Note that if
1167 -- the code generated by Build_Array_Aggr_Code is executed then these
1168 -- bounds are OK. Otherwise a Constraint_Error would have been raised.
1170 Aggr_Low : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_L);
1171 Aggr_High : constant Node_Id := Duplicate_Subexpr_No_Checks (Aggr_H);
1172 -- After Duplicate_Subexpr these are side-effect free
1177 Nb_Choices : Nat := 0;
1178 Table : Case_Table_Type (1 .. Number_Of_Choices (N));
1179 -- Used to sort all the different choice values
1182 -- Number of elements in the positional aggregate
1184 New_Code : constant List_Id := New_List;
1186 -- Start of processing for Build_Array_Aggr_Code
1189 -- First before we start, a special case. if we have a bit packed
1190 -- array represented as a modular type, then clear the value to
1191 -- zero first, to ensure that unused bits are properly cleared.
1196 and then Is_Bit_Packed_Array (Typ)
1197 and then Is_Modular_Integer_Type (Packed_Array_Type (Typ))
1199 Append_To (New_Code,
1200 Make_Assignment_Statement (Loc,
1201 Name => New_Copy_Tree (Into),
1203 Unchecked_Convert_To (Typ,
1204 Make_Integer_Literal (Loc, Uint_0))));
1208 -- STEP 1: Process component associations
1209 -- For those associations that may generate a loop, initialize
1210 -- Loop_Actions to collect inserted actions that may be crated.
1212 if No (Expressions (N)) then
1214 -- STEP 1 (a): Sort the discrete choices
1216 Assoc := First (Component_Associations (N));
1217 while Present (Assoc) loop
1218 Choice := First (Choices (Assoc));
1219 while Present (Choice) loop
1220 if Nkind (Choice) = N_Others_Choice then
1221 Set_Loop_Actions (Assoc, New_List);
1223 if Box_Present (Assoc) then
1224 Others_Mbox_Present := True;
1226 Others_Expr := Expression (Assoc);
1231 Get_Index_Bounds (Choice, Low, High);
1234 Set_Loop_Actions (Assoc, New_List);
1237 Nb_Choices := Nb_Choices + 1;
1238 if Box_Present (Assoc) then
1239 Table (Nb_Choices) := (Choice_Lo => Low,
1241 Choice_Node => Empty);
1243 Table (Nb_Choices) := (Choice_Lo => Low,
1245 Choice_Node => Expression (Assoc));
1253 -- If there is more than one set of choices these must be static
1254 -- and we can therefore sort them. Remember that Nb_Choices does not
1255 -- account for an others choice.
1257 if Nb_Choices > 1 then
1258 Sort_Case_Table (Table);
1261 -- STEP 1 (b): take care of the whole set of discrete choices.
1263 for J in 1 .. Nb_Choices loop
1264 Low := Table (J).Choice_Lo;
1265 High := Table (J).Choice_Hi;
1266 Expr := Table (J).Choice_Node;
1267 Append_List (Gen_Loop (Low, High, Expr), To => New_Code);
1270 -- STEP 1 (c): generate the remaining loops to cover others choice
1271 -- We don't need to generate loops over empty gaps, but if there is
1272 -- a single empty range we must analyze the expression for semantics
1274 if Present (Others_Expr) or else Others_Mbox_Present then
1276 First : Boolean := True;
1279 for J in 0 .. Nb_Choices loop
1283 Low := Add (1, To => Table (J).Choice_Hi);
1286 if J = Nb_Choices then
1289 High := Add (-1, To => Table (J + 1).Choice_Lo);
1292 -- If this is an expansion within an init proc, make
1293 -- sure that discriminant references are replaced by
1294 -- the corresponding discriminal.
1296 if Inside_Init_Proc then
1297 if Is_Entity_Name (Low)
1298 and then Ekind (Entity (Low)) = E_Discriminant
1300 Set_Entity (Low, Discriminal (Entity (Low)));
1303 if Is_Entity_Name (High)
1304 and then Ekind (Entity (High)) = E_Discriminant
1306 Set_Entity (High, Discriminal (Entity (High)));
1311 or else not Empty_Range (Low, High)
1315 (Gen_Loop (Low, High, Others_Expr), To => New_Code);
1321 -- STEP 2: Process positional components
1324 -- STEP 2 (a): Generate the assignments for each positional element
1325 -- Note that here we have to use Aggr_L rather than Aggr_Low because
1326 -- Aggr_L is analyzed and Add wants an analyzed expression.
1328 Expr := First (Expressions (N));
1331 while Present (Expr) loop
1332 Nb_Elements := Nb_Elements + 1;
1333 Append_List (Gen_Assign (Add (Nb_Elements, To => Aggr_L), Expr),
1338 -- STEP 2 (b): Generate final loop if an others choice is present
1339 -- Here Nb_Elements gives the offset of the last positional element.
1341 if Present (Component_Associations (N)) then
1342 Assoc := Last (Component_Associations (N));
1344 -- Ada 2005 (AI-287)
1346 if Box_Present (Assoc) then
1347 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1352 Expr := Expression (Assoc);
1354 Append_List (Gen_While (Add (Nb_Elements, To => Aggr_L),
1363 end Build_Array_Aggr_Code;
1365 ----------------------------
1366 -- Build_Record_Aggr_Code --
1367 ----------------------------
1369 function Build_Record_Aggr_Code
1373 Flist : Node_Id := Empty;
1374 Obj : Entity_Id := Empty;
1375 Is_Limited_Ancestor_Expansion : Boolean := False) return List_Id
1377 Loc : constant Source_Ptr := Sloc (N);
1378 L : constant List_Id := New_List;
1379 Start_L : constant List_Id := New_List;
1380 N_Typ : constant Entity_Id := Etype (N);
1386 Comp_Type : Entity_Id;
1387 Selector : Entity_Id;
1388 Comp_Expr : Node_Id;
1391 Internal_Final_List : Node_Id;
1393 -- If this is an internal aggregate, the External_Final_List is an
1394 -- expression for the controller record of the enclosing type.
1395 -- If the current aggregate has several controlled components, this
1396 -- expression will appear in several calls to attach to the finali-
1397 -- zation list, and it must not be shared.
1399 External_Final_List : Node_Id;
1400 Ancestor_Is_Expression : Boolean := False;
1401 Ancestor_Is_Subtype_Mark : Boolean := False;
1403 Init_Typ : Entity_Id := Empty;
1406 function Get_Constraint_Association (T : Entity_Id) return Node_Id;
1407 -- Returns the first discriminant association in the constraint
1408 -- associated with T, if any, otherwise returns Empty.
1410 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id;
1411 -- Returns the value that the given discriminant of an ancestor
1412 -- type should receive (in the absence of a conflict with the
1413 -- value provided by an ancestor part of an extension aggregate).
1415 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id);
1416 -- Check that each of the discriminant values defined by the
1417 -- ancestor part of an extension aggregate match the corresponding
1418 -- values provided by either an association of the aggregate or
1419 -- by the constraint imposed by a parent type (RM95-4.3.2(8)).
1421 function Init_Controller
1426 Init_Pr : Boolean) return List_Id;
1427 -- returns the list of statements necessary to initialize the internal
1428 -- controller of the (possible) ancestor typ into target and attach
1429 -- it to finalization list F. Init_Pr conditions the call to the
1430 -- init proc since it may already be done due to ancestor initialization
1432 ---------------------------------
1433 -- Ancestor_Discriminant_Value --
1434 ---------------------------------
1436 function Ancestor_Discriminant_Value (Disc : Entity_Id) return Node_Id is
1438 Assoc_Elmt : Elmt_Id;
1439 Aggr_Comp : Entity_Id;
1440 Corresp_Disc : Entity_Id;
1441 Current_Typ : Entity_Id := Base_Type (Typ);
1442 Parent_Typ : Entity_Id;
1443 Parent_Disc : Entity_Id;
1444 Save_Assoc : Node_Id := Empty;
1447 -- First check any discriminant associations to see if
1448 -- any of them provide a value for the discriminant.
1450 if Present (Discriminant_Specifications (Parent (Current_Typ))) then
1451 Assoc := First (Component_Associations (N));
1452 while Present (Assoc) loop
1453 Aggr_Comp := Entity (First (Choices (Assoc)));
1455 if Ekind (Aggr_Comp) = E_Discriminant then
1456 Save_Assoc := Expression (Assoc);
1458 Corresp_Disc := Corresponding_Discriminant (Aggr_Comp);
1459 while Present (Corresp_Disc) loop
1460 -- If found a corresponding discriminant then return
1461 -- the value given in the aggregate. (Note: this is
1462 -- not correct in the presence of side effects. ???)
1464 if Disc = Corresp_Disc then
1465 return Duplicate_Subexpr (Expression (Assoc));
1469 Corresponding_Discriminant (Corresp_Disc);
1477 -- No match found in aggregate, so chain up parent types to find
1478 -- a constraint that defines the value of the discriminant.
1480 Parent_Typ := Etype (Current_Typ);
1481 while Current_Typ /= Parent_Typ loop
1482 if Has_Discriminants (Parent_Typ) then
1483 Parent_Disc := First_Discriminant (Parent_Typ);
1485 -- We either get the association from the subtype indication
1486 -- of the type definition itself, or from the discriminant
1487 -- constraint associated with the type entity (which is
1488 -- preferable, but it's not always present ???)
1490 if Is_Empty_Elmt_List (
1491 Discriminant_Constraint (Current_Typ))
1493 Assoc := Get_Constraint_Association (Current_Typ);
1494 Assoc_Elmt := No_Elmt;
1497 First_Elmt (Discriminant_Constraint (Current_Typ));
1498 Assoc := Node (Assoc_Elmt);
1501 -- Traverse the discriminants of the parent type looking
1502 -- for one that corresponds.
1504 while Present (Parent_Disc) and then Present (Assoc) loop
1505 Corresp_Disc := Parent_Disc;
1506 while Present (Corresp_Disc)
1507 and then Disc /= Corresp_Disc
1510 Corresponding_Discriminant (Corresp_Disc);
1513 if Disc = Corresp_Disc then
1514 if Nkind (Assoc) = N_Discriminant_Association then
1515 Assoc := Expression (Assoc);
1518 -- If the located association directly denotes
1519 -- a discriminant, then use the value of a saved
1520 -- association of the aggregate. This is a kludge
1521 -- to handle certain cases involving multiple
1522 -- discriminants mapped to a single discriminant
1523 -- of a descendant. It's not clear how to locate the
1524 -- appropriate discriminant value for such cases. ???
1526 if Is_Entity_Name (Assoc)
1527 and then Ekind (Entity (Assoc)) = E_Discriminant
1529 Assoc := Save_Assoc;
1532 return Duplicate_Subexpr (Assoc);
1535 Next_Discriminant (Parent_Disc);
1537 if No (Assoc_Elmt) then
1540 Next_Elmt (Assoc_Elmt);
1541 if Present (Assoc_Elmt) then
1542 Assoc := Node (Assoc_Elmt);
1550 Current_Typ := Parent_Typ;
1551 Parent_Typ := Etype (Current_Typ);
1554 -- In some cases there's no ancestor value to locate (such as
1555 -- when an ancestor part given by an expression defines the
1556 -- discriminant value).
1559 end Ancestor_Discriminant_Value;
1561 ----------------------------------
1562 -- Check_Ancestor_Discriminants --
1563 ----------------------------------
1565 procedure Check_Ancestor_Discriminants (Anc_Typ : Entity_Id) is
1566 Discr : Entity_Id := First_Discriminant (Base_Type (Anc_Typ));
1567 Disc_Value : Node_Id;
1571 while Present (Discr) loop
1572 Disc_Value := Ancestor_Discriminant_Value (Discr);
1574 if Present (Disc_Value) then
1575 Cond := Make_Op_Ne (Loc,
1577 Make_Selected_Component (Loc,
1578 Prefix => New_Copy_Tree (Target),
1579 Selector_Name => New_Occurrence_Of (Discr, Loc)),
1580 Right_Opnd => Disc_Value);
1583 Make_Raise_Constraint_Error (Loc,
1585 Reason => CE_Discriminant_Check_Failed));
1588 Next_Discriminant (Discr);
1590 end Check_Ancestor_Discriminants;
1592 --------------------------------
1593 -- Get_Constraint_Association --
1594 --------------------------------
1596 function Get_Constraint_Association (T : Entity_Id) return Node_Id is
1597 Typ_Def : constant Node_Id := Type_Definition (Parent (T));
1598 Indic : constant Node_Id := Subtype_Indication (Typ_Def);
1601 -- ??? Also need to cover case of a type mark denoting a subtype
1604 if Nkind (Indic) = N_Subtype_Indication
1605 and then Present (Constraint (Indic))
1607 return First (Constraints (Constraint (Indic)));
1611 end Get_Constraint_Association;
1613 ---------------------
1614 -- Init_controller --
1615 ---------------------
1617 function Init_Controller
1622 Init_Pr : Boolean) return List_Id
1624 L : constant List_Id := New_List;
1629 -- init-proc (target._controller);
1630 -- initialize (target._controller);
1631 -- Attach_to_Final_List (target._controller, F);
1634 Make_Selected_Component (Loc,
1635 Prefix => Convert_To (Typ, New_Copy_Tree (Target)),
1636 Selector_Name => Make_Identifier (Loc, Name_uController));
1637 Set_Assignment_OK (Ref);
1639 -- Ada 2005 (AI-287): Give support to default initialization of
1640 -- limited types and components.
1642 if (Nkind (Target) = N_Identifier
1643 and then Present (Etype (Target))
1644 and then Is_Limited_Type (Etype (Target)))
1646 (Nkind (Target) = N_Selected_Component
1647 and then Present (Etype (Selector_Name (Target)))
1648 and then Is_Limited_Type (Etype (Selector_Name (Target))))
1650 (Nkind (Target) = N_Unchecked_Type_Conversion
1651 and then Present (Etype (Target))
1652 and then Is_Limited_Type (Etype (Target)))
1654 (Nkind (Target) = N_Unchecked_Expression
1655 and then Nkind (Expression (Target)) = N_Indexed_Component
1656 and then Present (Etype (Prefix (Expression (Target))))
1657 and then Is_Limited_Type (Etype (Prefix (Expression (Target)))))
1661 Build_Initialization_Call (Loc,
1663 Typ => RTE (RE_Limited_Record_Controller),
1664 In_Init_Proc => Within_Init_Proc));
1668 Make_Procedure_Call_Statement (Loc,
1671 (Find_Prim_Op (RTE (RE_Limited_Record_Controller),
1672 Name_Initialize), Loc),
1673 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
1678 Build_Initialization_Call (Loc,
1680 Typ => RTE (RE_Record_Controller),
1681 In_Init_Proc => Within_Init_Proc));
1685 Make_Procedure_Call_Statement (Loc,
1687 New_Reference_To (Find_Prim_Op (RTE (RE_Record_Controller),
1688 Name_Initialize), Loc),
1689 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
1695 Obj_Ref => New_Copy_Tree (Ref),
1697 With_Attach => Attach));
1699 end Init_Controller;
1701 -- Start of processing for Build_Record_Aggr_Code
1704 -- Deal with the ancestor part of extension aggregates
1705 -- or with the discriminants of the root type
1707 if Nkind (N) = N_Extension_Aggregate then
1709 A : constant Node_Id := Ancestor_Part (N);
1712 -- If the ancestor part is a subtype mark "T", we generate
1714 -- init-proc (T(tmp)); if T is constrained and
1715 -- init-proc (S(tmp)); where S applies an appropriate
1716 -- constraint if T is unconstrained
1718 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
1719 Ancestor_Is_Subtype_Mark := True;
1721 if Is_Constrained (Entity (A)) then
1722 Init_Typ := Entity (A);
1724 -- For an ancestor part given by an unconstrained type
1725 -- mark, create a subtype constrained by appropriate
1726 -- corresponding discriminant values coming from either
1727 -- associations of the aggregate or a constraint on
1728 -- a parent type. The subtype will be used to generate
1729 -- the correct default value for the ancestor part.
1731 elsif Has_Discriminants (Entity (A)) then
1733 Anc_Typ : constant Entity_Id := Entity (A);
1734 Anc_Constr : constant List_Id := New_List;
1735 Discrim : Entity_Id;
1736 Disc_Value : Node_Id;
1737 New_Indic : Node_Id;
1738 Subt_Decl : Node_Id;
1741 Discrim := First_Discriminant (Anc_Typ);
1742 while Present (Discrim) loop
1743 Disc_Value := Ancestor_Discriminant_Value (Discrim);
1744 Append_To (Anc_Constr, Disc_Value);
1745 Next_Discriminant (Discrim);
1749 Make_Subtype_Indication (Loc,
1750 Subtype_Mark => New_Occurrence_Of (Anc_Typ, Loc),
1752 Make_Index_Or_Discriminant_Constraint (Loc,
1753 Constraints => Anc_Constr));
1755 Init_Typ := Create_Itype (Ekind (Anc_Typ), N);
1758 Make_Subtype_Declaration (Loc,
1759 Defining_Identifier => Init_Typ,
1760 Subtype_Indication => New_Indic);
1762 -- Itypes must be analyzed with checks off
1763 -- Declaration must have a parent for proper
1764 -- handling of subsidiary actions.
1766 Set_Parent (Subt_Decl, N);
1767 Analyze (Subt_Decl, Suppress => All_Checks);
1771 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
1772 Set_Assignment_OK (Ref);
1774 if Has_Default_Init_Comps (N)
1775 or else Has_Task (Base_Type (Init_Typ))
1777 Append_List_To (Start_L,
1778 Build_Initialization_Call (Loc,
1781 In_Init_Proc => Within_Init_Proc,
1782 With_Default_Init => True));
1784 Append_List_To (Start_L,
1785 Build_Initialization_Call (Loc,
1788 In_Init_Proc => Within_Init_Proc));
1791 if Is_Constrained (Entity (A))
1792 and then Has_Discriminants (Entity (A))
1794 Check_Ancestor_Discriminants (Entity (A));
1797 -- Ada 2005 (AI-287): If the ancestor part is a limited type,
1798 -- a recursive call expands the ancestor.
1800 elsif Is_Limited_Type (Etype (A)) then
1801 Ancestor_Is_Expression := True;
1803 Append_List_To (Start_L,
1804 Build_Record_Aggr_Code (
1805 N => Expression (A),
1806 Typ => Etype (Expression (A)),
1810 Is_Limited_Ancestor_Expansion => True));
1812 -- If the ancestor part is an expression "E", we generate
1816 Ancestor_Is_Expression := True;
1817 Init_Typ := Etype (A);
1819 -- Assign the tag before doing the assignment to make sure
1820 -- that the dispatching call in the subsequent deep_adjust
1821 -- works properly (unless Java_VM, where tags are implicit).
1825 Make_OK_Assignment_Statement (Loc,
1827 Make_Selected_Component (Loc,
1828 Prefix => New_Copy_Tree (Target),
1829 Selector_Name => New_Reference_To (
1830 Tag_Component (Base_Type (Typ)), Loc)),
1833 Unchecked_Convert_To (RTE (RE_Tag),
1835 Access_Disp_Table (Base_Type (Typ)), Loc)));
1837 Set_Assignment_OK (Name (Instr));
1838 Append_To (L, Instr);
1841 -- If the ancestor part is an aggregate, force its full
1842 -- expansion, which was delayed.
1844 if Nkind (A) = N_Qualified_Expression
1845 and then (Nkind (Expression (A)) = N_Aggregate
1847 Nkind (Expression (A)) = N_Extension_Aggregate)
1849 Set_Analyzed (A, False);
1850 Set_Analyzed (Expression (A), False);
1853 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
1854 Set_Assignment_OK (Ref);
1856 Make_Unsuppress_Block (Loc,
1857 Name_Discriminant_Check,
1859 Make_OK_Assignment_Statement (Loc,
1861 Expression => A))));
1863 if Has_Discriminants (Init_Typ) then
1864 Check_Ancestor_Discriminants (Init_Typ);
1869 -- Normal case (not an extension aggregate)
1872 -- Generate the discriminant expressions, component by component.
1873 -- If the base type is an unchecked union, the discriminants are
1874 -- unknown to the back-end and absent from a value of the type, so
1875 -- assignments for them are not emitted.
1877 if Has_Discriminants (Typ)
1878 and then not Is_Unchecked_Union (Base_Type (Typ))
1880 -- ??? The discriminants of the object not inherited in the type
1881 -- of the object should be initialized here
1885 -- Generate discriminant init values
1888 Discriminant : Entity_Id;
1889 Discriminant_Value : Node_Id;
1892 Discriminant := First_Stored_Discriminant (Typ);
1894 while Present (Discriminant) loop
1897 Make_Selected_Component (Loc,
1898 Prefix => New_Copy_Tree (Target),
1899 Selector_Name => New_Occurrence_Of (Discriminant, Loc));
1901 Discriminant_Value :=
1902 Get_Discriminant_Value (
1905 Discriminant_Constraint (N_Typ));
1908 Make_OK_Assignment_Statement (Loc,
1910 Expression => New_Copy_Tree (Discriminant_Value));
1912 Set_No_Ctrl_Actions (Instr);
1913 Append_To (L, Instr);
1915 Next_Stored_Discriminant (Discriminant);
1921 -- Generate the assignments, component by component
1923 -- tmp.comp1 := Expr1_From_Aggr;
1924 -- tmp.comp2 := Expr2_From_Aggr;
1927 Comp := First (Component_Associations (N));
1928 while Present (Comp) loop
1929 Selector := Entity (First (Choices (Comp)));
1931 -- Ada 2005 (AI-287): Default initialization of a limited component
1933 if Box_Present (Comp)
1934 and then Is_Limited_Type (Etype (Selector))
1936 -- Ada 2005 (AI-287): If the component type has tasks then
1937 -- generate the activation chain and master entities (except
1938 -- in case of an allocator because in that case these entities
1939 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
1942 Ctype : constant Entity_Id := Etype (Selector);
1943 Inside_Allocator : Boolean := False;
1944 P : Node_Id := Parent (N);
1947 if Is_Task_Type (Ctype) or else Has_Task (Ctype) then
1948 while Present (P) loop
1949 if Nkind (P) = N_Allocator then
1950 Inside_Allocator := True;
1957 if not Inside_Init_Proc and not Inside_Allocator then
1958 Build_Activation_Chain_Entity (N);
1960 if not Has_Master_Entity (Current_Scope) then
1961 Build_Master_Entity (Etype (N));
1968 Build_Initialization_Call (Loc,
1969 Id_Ref => Make_Selected_Component (Loc,
1970 Prefix => New_Copy_Tree (Target),
1971 Selector_Name => New_Occurrence_Of (Selector,
1973 Typ => Etype (Selector),
1974 With_Default_Init => True));
1981 if Ekind (Selector) /= E_Discriminant
1982 or else Nkind (N) = N_Extension_Aggregate
1984 Comp_Type := Etype (Selector);
1986 Make_Selected_Component (Loc,
1987 Prefix => New_Copy_Tree (Target),
1988 Selector_Name => New_Occurrence_Of (Selector, Loc));
1990 if Nkind (Expression (Comp)) = N_Qualified_Expression then
1991 Expr_Q := Expression (Expression (Comp));
1993 Expr_Q := Expression (Comp);
1996 -- The controller is the one of the parent type defining
1997 -- the component (in case of inherited components).
1999 if Controlled_Type (Comp_Type) then
2000 Internal_Final_List :=
2001 Make_Selected_Component (Loc,
2002 Prefix => Convert_To (
2003 Scope (Original_Record_Component (Selector)),
2004 New_Copy_Tree (Target)),
2006 Make_Identifier (Loc, Name_uController));
2008 Internal_Final_List :=
2009 Make_Selected_Component (Loc,
2010 Prefix => Internal_Final_List,
2011 Selector_Name => Make_Identifier (Loc, Name_F));
2013 -- The internal final list can be part of a constant object
2015 Set_Assignment_OK (Internal_Final_List);
2018 Internal_Final_List := Empty;
2023 if Is_Delayed_Aggregate (Expr_Q) then
2025 Late_Expansion (Expr_Q, Comp_Type, Comp_Expr,
2026 Internal_Final_List));
2030 Make_OK_Assignment_Statement (Loc,
2032 Expression => Expression (Comp));
2034 Set_No_Ctrl_Actions (Instr);
2035 Append_To (L, Instr);
2037 -- Adjust the tag if tagged (because of possible view
2038 -- conversions), unless compiling for the Java VM
2039 -- where tags are implicit.
2041 -- tmp.comp._tag := comp_typ'tag;
2043 if Is_Tagged_Type (Comp_Type) and then not Java_VM then
2045 Make_OK_Assignment_Statement (Loc,
2047 Make_Selected_Component (Loc,
2048 Prefix => New_Copy_Tree (Comp_Expr),
2050 New_Reference_To (Tag_Component (Comp_Type), Loc)),
2053 Unchecked_Convert_To (RTE (RE_Tag),
2055 Access_Disp_Table (Comp_Type), Loc)));
2057 Append_To (L, Instr);
2060 -- Adjust and Attach the component to the proper controller
2061 -- Adjust (tmp.comp);
2062 -- Attach_To_Final_List (tmp.comp,
2063 -- comp_typ (tmp)._record_controller.f)
2065 if Controlled_Type (Comp_Type) then
2068 Ref => New_Copy_Tree (Comp_Expr),
2070 Flist_Ref => Internal_Final_List,
2071 With_Attach => Make_Integer_Literal (Loc, 1)));
2077 elsif Ekind (Selector) = E_Discriminant
2078 and then Nkind (N) /= N_Extension_Aggregate
2079 and then Nkind (Parent (N)) = N_Component_Association
2080 and then Is_Constrained (Typ)
2082 -- We must check that the discriminant value imposed by the
2083 -- context is the same as the value given in the subaggregate,
2084 -- because after the expansion into assignments there is no
2085 -- record on which to perform a regular discriminant check.
2092 D_Val := First_Elmt (Discriminant_Constraint (Typ));
2093 Disc := First_Discriminant (Typ);
2095 while Chars (Disc) /= Chars (Selector) loop
2096 Next_Discriminant (Disc);
2100 pragma Assert (Present (D_Val));
2103 Make_Raise_Constraint_Error (Loc,
2106 Left_Opnd => New_Copy_Tree (Node (D_Val)),
2107 Right_Opnd => Expression (Comp)),
2108 Reason => CE_Discriminant_Check_Failed));
2117 -- If the type is tagged, the tag needs to be initialized (unless
2118 -- compiling for the Java VM where tags are implicit). It is done
2119 -- late in the initialization process because in some cases, we call
2120 -- the init proc of an ancestor which will not leave out the right tag
2122 if Ancestor_Is_Expression then
2125 elsif Is_Tagged_Type (Typ) and then not Java_VM then
2127 Make_OK_Assignment_Statement (Loc,
2129 Make_Selected_Component (Loc,
2130 Prefix => New_Copy_Tree (Target),
2132 New_Reference_To (Tag_Component (Base_Type (Typ)), Loc)),
2135 Unchecked_Convert_To (RTE (RE_Tag),
2136 New_Reference_To (Access_Disp_Table (Base_Type (Typ)), Loc)));
2138 Append_To (L, Instr);
2141 -- Now deal with the various controlled type data structure
2145 and then Finalize_Storage_Only (Typ)
2146 and then (Is_Library_Level_Entity (Obj)
2147 or else Entity (Constant_Value (RTE (RE_Garbage_Collected)))
2150 Attach := Make_Integer_Literal (Loc, 0);
2152 elsif Nkind (Parent (N)) = N_Qualified_Expression
2153 and then Nkind (Parent (Parent (N))) = N_Allocator
2155 Attach := Make_Integer_Literal (Loc, 2);
2158 Attach := Make_Integer_Literal (Loc, 1);
2161 -- Determine the external finalization list. It is either the
2162 -- finalization list of the outer-scope or the one coming from
2163 -- an outer aggregate. When the target is not a temporary, the
2164 -- proper scope is the scope of the target rather than the
2165 -- potentially transient current scope.
2167 if Controlled_Type (Typ) then
2168 if Present (Flist) then
2169 External_Final_List := New_Copy_Tree (Flist);
2171 elsif Is_Entity_Name (Target)
2172 and then Present (Scope (Entity (Target)))
2174 External_Final_List := Find_Final_List (Scope (Entity (Target)));
2177 External_Final_List := Find_Final_List (Current_Scope);
2181 External_Final_List := Empty;
2184 -- Initialize and attach the outer object in the is_controlled case
2186 if Is_Controlled (Typ) then
2187 if Ancestor_Is_Subtype_Mark then
2188 Ref := Convert_To (Init_Typ, New_Copy_Tree (Target));
2189 Set_Assignment_OK (Ref);
2191 Make_Procedure_Call_Statement (Loc,
2192 Name => New_Reference_To (
2193 Find_Prim_Op (Init_Typ, Name_Initialize), Loc),
2194 Parameter_Associations => New_List (New_Copy_Tree (Ref))));
2197 if not Has_Controlled_Component (Typ) then
2198 Ref := New_Copy_Tree (Target);
2199 Set_Assignment_OK (Ref);
2203 Flist_Ref => New_Copy_Tree (External_Final_List),
2204 With_Attach => Attach));
2208 -- In the Has_Controlled component case, all the intermediate
2209 -- controllers must be initialized
2211 if Has_Controlled_Component (Typ)
2212 and not Is_Limited_Ancestor_Expansion
2215 Inner_Typ : Entity_Id;
2216 Outer_Typ : Entity_Id;
2221 Outer_Typ := Base_Type (Typ);
2223 -- Find outer type with a controller
2225 while Outer_Typ /= Init_Typ
2226 and then not Has_New_Controlled_Component (Outer_Typ)
2228 Outer_Typ := Etype (Outer_Typ);
2231 -- Attach it to the outer record controller to the
2232 -- external final list
2234 if Outer_Typ = Init_Typ then
2235 Append_List_To (Start_L,
2239 F => External_Final_List,
2241 Init_Pr => Ancestor_Is_Expression));
2244 Inner_Typ := Init_Typ;
2247 Append_List_To (Start_L,
2251 F => External_Final_List,
2255 Inner_Typ := Etype (Outer_Typ);
2257 not Is_Tagged_Type (Typ) or else Inner_Typ = Outer_Typ;
2260 -- The outer object has to be attached as well
2262 if Is_Controlled (Typ) then
2263 Ref := New_Copy_Tree (Target);
2264 Set_Assignment_OK (Ref);
2268 Flist_Ref => New_Copy_Tree (External_Final_List),
2269 With_Attach => New_Copy_Tree (Attach)));
2272 -- Initialize the internal controllers for tagged types with
2273 -- more than one controller.
2275 while not At_Root and then Inner_Typ /= Init_Typ loop
2276 if Has_New_Controlled_Component (Inner_Typ) then
2278 Make_Selected_Component (Loc,
2279 Prefix => Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2281 Make_Identifier (Loc, Name_uController));
2283 Make_Selected_Component (Loc,
2285 Selector_Name => Make_Identifier (Loc, Name_F));
2287 Append_List_To (Start_L,
2292 Attach => Make_Integer_Literal (Loc, 1),
2294 Outer_Typ := Inner_Typ;
2299 At_Root := Inner_Typ = Etype (Inner_Typ);
2300 Inner_Typ := Etype (Inner_Typ);
2303 -- If not done yet attach the controller of the ancestor part
2305 if Outer_Typ /= Init_Typ
2306 and then Inner_Typ = Init_Typ
2307 and then Has_Controlled_Component (Init_Typ)
2310 Make_Selected_Component (Loc,
2311 Prefix => Convert_To (Outer_Typ, New_Copy_Tree (Target)),
2312 Selector_Name => Make_Identifier (Loc, Name_uController));
2314 Make_Selected_Component (Loc,
2316 Selector_Name => Make_Identifier (Loc, Name_F));
2318 Attach := Make_Integer_Literal (Loc, 1);
2319 Append_List_To (Start_L,
2325 Init_Pr => Ancestor_Is_Expression));
2330 Append_List_To (Start_L, L);
2332 end Build_Record_Aggr_Code;
2334 -------------------------------
2335 -- Convert_Aggr_In_Allocator --
2336 -------------------------------
2338 procedure Convert_Aggr_In_Allocator (Decl, Aggr : Node_Id) is
2339 Loc : constant Source_Ptr := Sloc (Aggr);
2340 Typ : constant Entity_Id := Etype (Aggr);
2341 Temp : constant Entity_Id := Defining_Identifier (Decl);
2343 Occ : constant Node_Id :=
2344 Unchecked_Convert_To (Typ,
2345 Make_Explicit_Dereference (Loc,
2346 New_Reference_To (Temp, Loc)));
2348 Access_Type : constant Entity_Id := Etype (Temp);
2351 if Has_Default_Init_Comps (Aggr) then
2353 L : constant List_Id := New_List;
2354 Init_Stmts : List_Id;
2357 Init_Stmts := Late_Expansion (Aggr, Typ, Occ,
2358 Find_Final_List (Access_Type),
2359 Associated_Final_Chain (Base_Type (Access_Type)));
2361 Build_Task_Allocate_Block_With_Init_Stmts (L, Aggr, Init_Stmts);
2362 Insert_Actions_After (Decl, L);
2366 Insert_Actions_After (Decl,
2367 Late_Expansion (Aggr, Typ, Occ,
2368 Find_Final_List (Access_Type),
2369 Associated_Final_Chain (Base_Type (Access_Type))));
2371 end Convert_Aggr_In_Allocator;
2373 --------------------------------
2374 -- Convert_Aggr_In_Assignment --
2375 --------------------------------
2377 procedure Convert_Aggr_In_Assignment (N : Node_Id) is
2378 Aggr : Node_Id := Expression (N);
2379 Typ : constant Entity_Id := Etype (Aggr);
2380 Occ : constant Node_Id := New_Copy_Tree (Name (N));
2383 if Nkind (Aggr) = N_Qualified_Expression then
2384 Aggr := Expression (Aggr);
2387 Insert_Actions_After (N,
2388 Late_Expansion (Aggr, Typ, Occ,
2389 Find_Final_List (Typ, New_Copy_Tree (Occ))));
2390 end Convert_Aggr_In_Assignment;
2392 ---------------------------------
2393 -- Convert_Aggr_In_Object_Decl --
2394 ---------------------------------
2396 procedure Convert_Aggr_In_Object_Decl (N : Node_Id) is
2397 Obj : constant Entity_Id := Defining_Identifier (N);
2398 Aggr : Node_Id := Expression (N);
2399 Loc : constant Source_Ptr := Sloc (Aggr);
2400 Typ : constant Entity_Id := Etype (Aggr);
2401 Occ : constant Node_Id := New_Occurrence_Of (Obj, Loc);
2403 function Discriminants_Ok return Boolean;
2404 -- If the object type is constrained, the discriminants in the
2405 -- aggregate must be checked against the discriminants of the subtype.
2406 -- This cannot be done using Apply_Discriminant_Checks because after
2407 -- expansion there is no aggregate left to check.
2409 ----------------------
2410 -- Discriminants_Ok --
2411 ----------------------
2413 function Discriminants_Ok return Boolean is
2414 Cond : Node_Id := Empty;
2423 D := First_Discriminant (Typ);
2424 Disc1 := First_Elmt (Discriminant_Constraint (Typ));
2425 Disc2 := First_Elmt (Discriminant_Constraint (Etype (Obj)));
2427 while Present (Disc1) and then Present (Disc2) loop
2428 Val1 := Node (Disc1);
2429 Val2 := Node (Disc2);
2431 if not Is_OK_Static_Expression (Val1)
2432 or else not Is_OK_Static_Expression (Val2)
2434 Check := Make_Op_Ne (Loc,
2435 Left_Opnd => Duplicate_Subexpr (Val1),
2436 Right_Opnd => Duplicate_Subexpr (Val2));
2442 Cond := Make_Or_Else (Loc,
2444 Right_Opnd => Check);
2447 elsif Expr_Value (Val1) /= Expr_Value (Val2) then
2448 Apply_Compile_Time_Constraint_Error (Aggr,
2449 Msg => "incorrect value for discriminant&?",
2450 Reason => CE_Discriminant_Check_Failed,
2455 Next_Discriminant (D);
2460 -- If any discriminant constraint is non-static, emit a check.
2462 if Present (Cond) then
2464 Make_Raise_Constraint_Error (Loc,
2466 Reason => CE_Discriminant_Check_Failed));
2470 end Discriminants_Ok;
2472 -- Start of processing for Convert_Aggr_In_Object_Decl
2475 Set_Assignment_OK (Occ);
2477 if Nkind (Aggr) = N_Qualified_Expression then
2478 Aggr := Expression (Aggr);
2481 if Has_Discriminants (Typ)
2482 and then Typ /= Etype (Obj)
2483 and then Is_Constrained (Etype (Obj))
2484 and then not Discriminants_Ok
2489 Insert_Actions_After (N, Late_Expansion (Aggr, Typ, Occ, Obj => Obj));
2490 Set_No_Initialization (N);
2491 Initialize_Discriminants (N, Typ);
2492 end Convert_Aggr_In_Object_Decl;
2494 ----------------------------
2495 -- Convert_To_Assignments --
2496 ----------------------------
2498 procedure Convert_To_Assignments (N : Node_Id; Typ : Entity_Id) is
2499 Loc : constant Source_Ptr := Sloc (N);
2503 Target_Expr : Node_Id;
2504 Parent_Kind : Node_Kind;
2505 Unc_Decl : Boolean := False;
2506 Parent_Node : Node_Id;
2509 Parent_Node := Parent (N);
2510 Parent_Kind := Nkind (Parent_Node);
2512 if Parent_Kind = N_Qualified_Expression then
2514 -- Check if we are in a unconstrained declaration because in this
2515 -- case the current delayed expansion mechanism doesn't work when
2516 -- the declared object size depend on the initializing expr.
2519 Parent_Node := Parent (Parent_Node);
2520 Parent_Kind := Nkind (Parent_Node);
2522 if Parent_Kind = N_Object_Declaration then
2524 not Is_Entity_Name (Object_Definition (Parent_Node))
2525 or else Has_Discriminants
2526 (Entity (Object_Definition (Parent_Node)))
2527 or else Is_Class_Wide_Type
2528 (Entity (Object_Definition (Parent_Node)));
2533 -- Just set the Delay flag in the following cases where the
2534 -- transformation will be done top down from above
2536 -- - internal aggregate (transformed when expanding the parent)
2537 -- - allocators (see Convert_Aggr_In_Allocator)
2538 -- - object decl (see Convert_Aggr_In_Object_Decl)
2539 -- - safe assignments (see Convert_Aggr_Assignments)
2540 -- so far only the assignments in the init procs are taken
2543 if Parent_Kind = N_Aggregate
2544 or else Parent_Kind = N_Extension_Aggregate
2545 or else Parent_Kind = N_Component_Association
2546 or else Parent_Kind = N_Allocator
2547 or else (Parent_Kind = N_Object_Declaration and then not Unc_Decl)
2548 or else (Parent_Kind = N_Assignment_Statement
2549 and then Inside_Init_Proc)
2551 Set_Expansion_Delayed (N);
2555 if Requires_Transient_Scope (Typ) then
2556 Establish_Transient_Scope (N, Sec_Stack =>
2557 Is_Controlled (Typ) or else Has_Controlled_Component (Typ));
2560 -- Create the temporary
2562 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
2565 Make_Object_Declaration (Loc,
2566 Defining_Identifier => Temp,
2567 Object_Definition => New_Occurrence_Of (Typ, Loc));
2569 Set_No_Initialization (Instr);
2570 Insert_Action (N, Instr);
2571 Initialize_Discriminants (Instr, Typ);
2572 Target_Expr := New_Occurrence_Of (Temp, Loc);
2574 Insert_Actions (N, Build_Record_Aggr_Code (N, Typ, Target_Expr));
2575 Rewrite (N, New_Occurrence_Of (Temp, Loc));
2576 Analyze_And_Resolve (N, Typ);
2577 end Convert_To_Assignments;
2579 ---------------------------
2580 -- Convert_To_Positional --
2581 ---------------------------
2583 procedure Convert_To_Positional
2585 Max_Others_Replicate : Nat := 5;
2586 Handle_Bit_Packed : Boolean := False)
2588 Typ : constant Entity_Id := Etype (N);
2593 Ixb : Node_Id) return Boolean;
2594 -- Convert the aggregate into a purely positional form if possible.
2596 function Is_Flat (N : Node_Id; Dims : Int) return Boolean;
2597 -- Non trivial for multidimensional aggregate.
2606 Ixb : Node_Id) return Boolean
2608 Loc : constant Source_Ptr := Sloc (N);
2609 Blo : constant Node_Id := Type_Low_Bound (Etype (Ixb));
2610 Lo : constant Node_Id := Type_Low_Bound (Etype (Ix));
2611 Hi : constant Node_Id := Type_High_Bound (Etype (Ix));
2615 -- The following constant determines the maximum size of an
2616 -- aggregate produced by converting named to positional
2617 -- notation (e.g. from others clauses). This avoids running
2618 -- away with attempts to convert huge aggregates.
2620 -- The normal limit is 5000, but we increase this limit to
2621 -- 2**24 (about 16 million) if Restrictions (No_Elaboration_Code)
2622 -- or Restrictions (No_Implicit_Loops) is specified, since in
2623 -- either case, we are at risk of declaring the program illegal
2624 -- because of this limit.
2626 Max_Aggr_Size : constant Nat :=
2627 5000 + (2 ** 24 - 5000) *
2629 (Restriction_Active (No_Elaboration_Code)
2631 Restriction_Active (No_Implicit_Loops));
2634 if Nkind (Original_Node (N)) = N_String_Literal then
2638 -- Bounds need to be known at compile time
2640 if not Compile_Time_Known_Value (Lo)
2641 or else not Compile_Time_Known_Value (Hi)
2646 -- Get bounds and check reasonable size (positive, not too large)
2647 -- Also only handle bounds starting at the base type low bound
2648 -- for now since the compiler isn't able to handle different low
2649 -- bounds yet. Case such as new String'(3..5 => ' ') will get
2650 -- the wrong bounds, though it seems that the aggregate should
2651 -- retain the bounds set on its Etype (see C64103E and CC1311B).
2653 Lov := Expr_Value (Lo);
2654 Hiv := Expr_Value (Hi);
2657 or else (Hiv - Lov > Max_Aggr_Size)
2658 or else not Compile_Time_Known_Value (Blo)
2659 or else (Lov /= Expr_Value (Blo))
2664 -- Bounds must be in integer range (for array Vals below)
2666 if not UI_Is_In_Int_Range (Lov)
2668 not UI_Is_In_Int_Range (Hiv)
2673 -- Determine if set of alternatives is suitable for conversion
2674 -- and build an array containing the values in sequence.
2677 Vals : array (UI_To_Int (Lov) .. UI_To_Int (Hiv))
2678 of Node_Id := (others => Empty);
2679 -- The values in the aggregate sorted appropriately
2682 -- Same data as Vals in list form
2685 -- Used to validate Max_Others_Replicate limit
2688 Num : Int := UI_To_Int (Lov);
2693 if Present (Expressions (N)) then
2694 Elmt := First (Expressions (N));
2696 while Present (Elmt) loop
2697 if Nkind (Elmt) = N_Aggregate
2698 and then Present (Next_Index (Ix))
2700 not Flatten (Elmt, Next_Index (Ix), Next_Index (Ixb))
2705 Vals (Num) := Relocate_Node (Elmt);
2712 if No (Component_Associations (N)) then
2716 Elmt := First (Component_Associations (N));
2718 if Nkind (Expression (Elmt)) = N_Aggregate then
2719 if Present (Next_Index (Ix))
2722 (Expression (Elmt), Next_Index (Ix), Next_Index (Ixb))
2728 Component_Loop : while Present (Elmt) loop
2729 Choice := First (Choices (Elmt));
2730 Choice_Loop : while Present (Choice) loop
2732 -- If we have an others choice, fill in the missing elements
2733 -- subject to the limit established by Max_Others_Replicate.
2735 if Nkind (Choice) = N_Others_Choice then
2738 for J in Vals'Range loop
2739 if No (Vals (J)) then
2740 Vals (J) := New_Copy_Tree (Expression (Elmt));
2741 Rep_Count := Rep_Count + 1;
2743 -- Check for maximum others replication. Note that
2744 -- we skip this test if either of the restrictions
2745 -- No_Elaboration_Code or No_Implicit_Loops is
2746 -- active, or if this is a preelaborable unit.
2749 P : constant Entity_Id :=
2750 Cunit_Entity (Current_Sem_Unit);
2753 if Restriction_Active (No_Elaboration_Code)
2754 or else Restriction_Active (No_Implicit_Loops)
2755 or else Is_Preelaborated (P)
2756 or else (Ekind (P) = E_Package_Body
2758 Is_Preelaborated (Spec_Entity (P)))
2762 elsif Rep_Count > Max_Others_Replicate then
2769 exit Component_Loop;
2771 -- Case of a subtype mark
2773 elsif Nkind (Choice) = N_Identifier
2774 and then Is_Type (Entity (Choice))
2776 Lo := Type_Low_Bound (Etype (Choice));
2777 Hi := Type_High_Bound (Etype (Choice));
2779 -- Case of subtype indication
2781 elsif Nkind (Choice) = N_Subtype_Indication then
2782 Lo := Low_Bound (Range_Expression (Constraint (Choice)));
2783 Hi := High_Bound (Range_Expression (Constraint (Choice)));
2787 elsif Nkind (Choice) = N_Range then
2788 Lo := Low_Bound (Choice);
2789 Hi := High_Bound (Choice);
2791 -- Normal subexpression case
2793 else pragma Assert (Nkind (Choice) in N_Subexpr);
2794 if not Compile_Time_Known_Value (Choice) then
2798 Vals (UI_To_Int (Expr_Value (Choice))) :=
2799 New_Copy_Tree (Expression (Elmt));
2804 -- Range cases merge with Lo,Hi said
2806 if not Compile_Time_Known_Value (Lo)
2808 not Compile_Time_Known_Value (Hi)
2812 for J in UI_To_Int (Expr_Value (Lo)) ..
2813 UI_To_Int (Expr_Value (Hi))
2815 Vals (J) := New_Copy_Tree (Expression (Elmt));
2821 end loop Choice_Loop;
2824 end loop Component_Loop;
2826 -- If we get here the conversion is possible
2829 for J in Vals'Range loop
2830 Append (Vals (J), Vlist);
2833 Rewrite (N, Make_Aggregate (Loc, Expressions => Vlist));
2834 Set_Aggregate_Bounds (N, Aggregate_Bounds (Original_Node (N)));
2843 function Is_Flat (N : Node_Id; Dims : Int) return Boolean is
2850 elsif Nkind (N) = N_Aggregate then
2851 if Present (Component_Associations (N)) then
2855 Elmt := First (Expressions (N));
2857 while Present (Elmt) loop
2858 if not Is_Flat (Elmt, Dims - 1) then
2872 -- Start of processing for Convert_To_Positional
2875 -- Ada 2005 (AI-287): Do not convert in case of default initialized
2876 -- components because in this case will need to call the corresponding
2879 if Has_Default_Init_Comps (N) then
2883 if Is_Flat (N, Number_Dimensions (Typ)) then
2887 if Is_Bit_Packed_Array (Typ)
2888 and then not Handle_Bit_Packed
2893 -- Do not convert to positional if controlled components are
2894 -- involved since these require special processing
2896 if Has_Controlled_Component (Typ) then
2900 if Flatten (N, First_Index (Typ), First_Index (Base_Type (Typ))) then
2901 Analyze_And_Resolve (N, Typ);
2903 end Convert_To_Positional;
2905 ----------------------------
2906 -- Expand_Array_Aggregate --
2907 ----------------------------
2909 -- Array aggregate expansion proceeds as follows:
2911 -- 1. If requested we generate code to perform all the array aggregate
2912 -- bound checks, specifically
2914 -- (a) Check that the index range defined by aggregate bounds is
2915 -- compatible with corresponding index subtype.
2917 -- (b) If an others choice is present check that no aggregate
2918 -- index is outside the bounds of the index constraint.
2920 -- (c) For multidimensional arrays make sure that all subaggregates
2921 -- corresponding to the same dimension have the same bounds.
2923 -- 2. Check for packed array aggregate which can be converted to a
2924 -- constant so that the aggregate disappeares completely.
2926 -- 3. Check case of nested aggregate. Generally nested aggregates are
2927 -- handled during the processing of the parent aggregate.
2929 -- 4. Check if the aggregate can be statically processed. If this is the
2930 -- case pass it as is to Gigi. Note that a necessary condition for
2931 -- static processing is that the aggregate be fully positional.
2933 -- 5. If in place aggregate expansion is possible (i.e. no need to create
2934 -- a temporary) then mark the aggregate as such and return. Otherwise
2935 -- create a new temporary and generate the appropriate initialization
2938 procedure Expand_Array_Aggregate (N : Node_Id) is
2939 Loc : constant Source_Ptr := Sloc (N);
2941 Typ : constant Entity_Id := Etype (N);
2942 Ctyp : constant Entity_Id := Component_Type (Typ);
2943 -- Typ is the correct constrained array subtype of the aggregate
2944 -- Ctyp is the corresponding component type.
2946 Aggr_Dimension : constant Pos := Number_Dimensions (Typ);
2947 -- Number of aggregate index dimensions.
2949 Aggr_Low : array (1 .. Aggr_Dimension) of Node_Id;
2950 Aggr_High : array (1 .. Aggr_Dimension) of Node_Id;
2951 -- Low and High bounds of the constraint for each aggregate index.
2953 Aggr_Index_Typ : array (1 .. Aggr_Dimension) of Entity_Id;
2954 -- The type of each index.
2956 Maybe_In_Place_OK : Boolean;
2957 -- If the type is neither controlled nor packed and the aggregate
2958 -- is the expression in an assignment, assignment in place may be
2959 -- possible, provided other conditions are met on the LHS.
2961 Others_Present : array (1 .. Aggr_Dimension) of Boolean :=
2963 -- If Others_Present (J) is True, then there is an others choice
2964 -- in one of the sub-aggregates of N at dimension J.
2966 procedure Build_Constrained_Type (Positional : Boolean);
2967 -- If the subtype is not static or unconstrained, build a constrained
2968 -- type using the computable sizes of the aggregate and its sub-
2971 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id);
2972 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
2975 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos);
2976 -- Checks that in a multi-dimensional array aggregate all subaggregates
2977 -- corresponding to the same dimension have the same bounds.
2978 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
2979 -- corresponding to the sub-aggregate.
2981 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos);
2982 -- Computes the values of array Others_Present. Sub_Aggr is the
2983 -- array sub-aggregate we start the computation from. Dim is the
2984 -- dimension corresponding to the sub-aggregate.
2986 function Has_Address_Clause (D : Node_Id) return Boolean;
2987 -- If the aggregate is the expression in an object declaration, it
2988 -- cannot be expanded in place. This function does a lookahead in the
2989 -- current declarative part to find an address clause for the object
2992 function In_Place_Assign_OK return Boolean;
2993 -- Simple predicate to determine whether an aggregate assignment can
2994 -- be done in place, because none of the new values can depend on the
2995 -- components of the target of the assignment.
2997 function Must_Slide (N : Node_Id; Typ : Entity_Id) return Boolean;
2998 -- A static aggregate in an object declaration can in most cases be
2999 -- expanded in place. The one exception is when the aggregate is given
3000 -- with component associations that specify different bounds from those
3001 -- of the type definition in the object declaration. In this rather
3002 -- pathological case the aggregate must slide, and we must introduce
3003 -- an intermediate temporary to hold it.
3005 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos);
3006 -- Checks that if an others choice is present in any sub-aggregate no
3007 -- aggregate index is outside the bounds of the index constraint.
3008 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
3009 -- corresponding to the sub-aggregate.
3011 ----------------------------
3012 -- Build_Constrained_Type --
3013 ----------------------------
3015 procedure Build_Constrained_Type (Positional : Boolean) is
3016 Loc : constant Source_Ptr := Sloc (N);
3017 Agg_Type : Entity_Id;
3020 Typ : constant Entity_Id := Etype (N);
3021 Indices : constant List_Id := New_List;
3027 Make_Defining_Identifier (
3028 Loc, New_Internal_Name ('A'));
3030 -- If the aggregate is purely positional, all its subaggregates
3031 -- have the same size. We collect the dimensions from the first
3032 -- subaggregate at each level.
3037 for D in 1 .. Number_Dimensions (Typ) loop
3038 Comp := First (Expressions (Sub_Agg));
3043 while Present (Comp) loop
3050 Low_Bound => Make_Integer_Literal (Loc, 1),
3052 Make_Integer_Literal (Loc, Num)),
3057 -- We know the aggregate type is unconstrained and the
3058 -- aggregate is not processable by the back end, therefore
3059 -- not necessarily positional. Retrieve the bounds of each
3060 -- dimension as computed earlier.
3062 for D in 1 .. Number_Dimensions (Typ) loop
3065 Low_Bound => Aggr_Low (D),
3066 High_Bound => Aggr_High (D)),
3072 Make_Full_Type_Declaration (Loc,
3073 Defining_Identifier => Agg_Type,
3075 Make_Constrained_Array_Definition (Loc,
3076 Discrete_Subtype_Definitions => Indices,
3077 Component_Definition =>
3078 Make_Component_Definition (Loc,
3079 Aliased_Present => False,
3080 Subtype_Indication =>
3081 New_Occurrence_Of (Component_Type (Typ), Loc))));
3083 Insert_Action (N, Decl);
3085 Set_Etype (N, Agg_Type);
3086 Set_Is_Itype (Agg_Type);
3087 Freeze_Itype (Agg_Type, N);
3088 end Build_Constrained_Type;
3094 procedure Check_Bounds (Aggr_Bounds : Node_Id; Index_Bounds : Node_Id) is
3101 Cond : Node_Id := Empty;
3104 Get_Index_Bounds (Aggr_Bounds, Aggr_Lo, Aggr_Hi);
3105 Get_Index_Bounds (Index_Bounds, Ind_Lo, Ind_Hi);
3107 -- Generate the following test:
3109 -- [constraint_error when
3110 -- Aggr_Lo <= Aggr_Hi and then
3111 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
3113 -- As an optimization try to see if some tests are trivially vacuos
3114 -- because we are comparing an expression against itself.
3116 if Aggr_Lo = Ind_Lo and then Aggr_Hi = Ind_Hi then
3119 elsif Aggr_Hi = Ind_Hi then
3122 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3123 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo));
3125 elsif Aggr_Lo = Ind_Lo then
3128 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
3129 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Hi));
3136 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3137 Right_Opnd => Duplicate_Subexpr_Move_Checks (Ind_Lo)),
3141 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
3142 Right_Opnd => Duplicate_Subexpr (Ind_Hi)));
3145 if Present (Cond) then
3150 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3151 Right_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi)),
3153 Right_Opnd => Cond);
3155 Set_Analyzed (Left_Opnd (Left_Opnd (Cond)), False);
3156 Set_Analyzed (Right_Opnd (Left_Opnd (Cond)), False);
3158 Make_Raise_Constraint_Error (Loc,
3160 Reason => CE_Length_Check_Failed));
3164 ----------------------------
3165 -- Check_Same_Aggr_Bounds --
3166 ----------------------------
3168 procedure Check_Same_Aggr_Bounds (Sub_Aggr : Node_Id; Dim : Pos) is
3169 Sub_Lo : constant Node_Id := Low_Bound (Aggregate_Bounds (Sub_Aggr));
3170 Sub_Hi : constant Node_Id := High_Bound (Aggregate_Bounds (Sub_Aggr));
3171 -- The bounds of this specific sub-aggregate.
3173 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
3174 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
3175 -- The bounds of the aggregate for this dimension
3177 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
3178 -- The index type for this dimension.
3180 Cond : Node_Id := Empty;
3186 -- If index checks are on generate the test
3188 -- [constraint_error when
3189 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
3191 -- As an optimization try to see if some tests are trivially vacuos
3192 -- because we are comparing an expression against itself. Also for
3193 -- the first dimension the test is trivially vacuous because there
3194 -- is just one aggregate for dimension 1.
3196 if Index_Checks_Suppressed (Ind_Typ) then
3200 or else (Aggr_Lo = Sub_Lo and then Aggr_Hi = Sub_Hi)
3204 elsif Aggr_Hi = Sub_Hi then
3207 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3208 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo));
3210 elsif Aggr_Lo = Sub_Lo then
3213 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Hi),
3214 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Hi));
3221 Left_Opnd => Duplicate_Subexpr_Move_Checks (Aggr_Lo),
3222 Right_Opnd => Duplicate_Subexpr_Move_Checks (Sub_Lo)),
3226 Left_Opnd => Duplicate_Subexpr (Aggr_Hi),
3227 Right_Opnd => Duplicate_Subexpr (Sub_Hi)));
3230 if Present (Cond) then
3232 Make_Raise_Constraint_Error (Loc,
3234 Reason => CE_Length_Check_Failed));
3237 -- Now look inside the sub-aggregate to see if there is more work
3239 if Dim < Aggr_Dimension then
3241 -- Process positional components
3243 if Present (Expressions (Sub_Aggr)) then
3244 Expr := First (Expressions (Sub_Aggr));
3245 while Present (Expr) loop
3246 Check_Same_Aggr_Bounds (Expr, Dim + 1);
3251 -- Process component associations
3253 if Present (Component_Associations (Sub_Aggr)) then
3254 Assoc := First (Component_Associations (Sub_Aggr));
3255 while Present (Assoc) loop
3256 Expr := Expression (Assoc);
3257 Check_Same_Aggr_Bounds (Expr, Dim + 1);
3262 end Check_Same_Aggr_Bounds;
3264 ----------------------------
3265 -- Compute_Others_Present --
3266 ----------------------------
3268 procedure Compute_Others_Present (Sub_Aggr : Node_Id; Dim : Pos) is
3273 if Present (Component_Associations (Sub_Aggr)) then
3274 Assoc := Last (Component_Associations (Sub_Aggr));
3276 if Nkind (First (Choices (Assoc))) = N_Others_Choice then
3277 Others_Present (Dim) := True;
3281 -- Now look inside the sub-aggregate to see if there is more work
3283 if Dim < Aggr_Dimension then
3285 -- Process positional components
3287 if Present (Expressions (Sub_Aggr)) then
3288 Expr := First (Expressions (Sub_Aggr));
3289 while Present (Expr) loop
3290 Compute_Others_Present (Expr, Dim + 1);
3295 -- Process component associations
3297 if Present (Component_Associations (Sub_Aggr)) then
3298 Assoc := First (Component_Associations (Sub_Aggr));
3299 while Present (Assoc) loop
3300 Expr := Expression (Assoc);
3301 Compute_Others_Present (Expr, Dim + 1);
3306 end Compute_Others_Present;
3308 ------------------------
3309 -- Has_Address_Clause --
3310 ------------------------
3312 function Has_Address_Clause (D : Node_Id) return Boolean is
3313 Id : constant Entity_Id := Defining_Identifier (D);
3314 Decl : Node_Id := Next (D);
3317 while Present (Decl) loop
3318 if Nkind (Decl) = N_At_Clause
3319 and then Chars (Identifier (Decl)) = Chars (Id)
3323 elsif Nkind (Decl) = N_Attribute_Definition_Clause
3324 and then Chars (Decl) = Name_Address
3325 and then Chars (Name (Decl)) = Chars (Id)
3334 end Has_Address_Clause;
3336 ------------------------
3337 -- In_Place_Assign_OK --
3338 ------------------------
3340 function In_Place_Assign_OK return Boolean is
3348 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean;
3349 -- Aggregates that consist of a single Others choice are safe
3350 -- if the single expression is.
3352 function Safe_Aggregate (Aggr : Node_Id) return Boolean;
3353 -- Check recursively that each component of a (sub)aggregate does
3354 -- not depend on the variable being assigned to.
3356 function Safe_Component (Expr : Node_Id) return Boolean;
3357 -- Verify that an expression cannot depend on the variable being
3358 -- assigned to. Room for improvement here (but less than before).
3360 -------------------------
3361 -- Is_Others_Aggregate --
3362 -------------------------
3364 function Is_Others_Aggregate (Aggr : Node_Id) return Boolean is
3366 return No (Expressions (Aggr))
3368 (First (Choices (First (Component_Associations (Aggr)))))
3370 end Is_Others_Aggregate;
3372 --------------------
3373 -- Safe_Aggregate --
3374 --------------------
3376 function Safe_Aggregate (Aggr : Node_Id) return Boolean is
3380 if Present (Expressions (Aggr)) then
3381 Expr := First (Expressions (Aggr));
3383 while Present (Expr) loop
3384 if Nkind (Expr) = N_Aggregate then
3385 if not Safe_Aggregate (Expr) then
3389 elsif not Safe_Component (Expr) then
3397 if Present (Component_Associations (Aggr)) then
3398 Expr := First (Component_Associations (Aggr));
3400 while Present (Expr) loop
3401 if Nkind (Expression (Expr)) = N_Aggregate then
3402 if not Safe_Aggregate (Expression (Expr)) then
3406 elsif not Safe_Component (Expression (Expr)) then
3417 --------------------
3418 -- Safe_Component --
3419 --------------------
3421 function Safe_Component (Expr : Node_Id) return Boolean is
3422 Comp : Node_Id := Expr;
3424 function Check_Component (Comp : Node_Id) return Boolean;
3425 -- Do the recursive traversal, after copy.
3427 ---------------------
3428 -- Check_Component --
3429 ---------------------
3431 function Check_Component (Comp : Node_Id) return Boolean is
3433 if Is_Overloaded (Comp) then
3437 return Compile_Time_Known_Value (Comp)
3439 or else (Is_Entity_Name (Comp)
3440 and then Present (Entity (Comp))
3441 and then No (Renamed_Object (Entity (Comp))))
3443 or else (Nkind (Comp) = N_Attribute_Reference
3444 and then Check_Component (Prefix (Comp)))
3446 or else (Nkind (Comp) in N_Binary_Op
3447 and then Check_Component (Left_Opnd (Comp))
3448 and then Check_Component (Right_Opnd (Comp)))
3450 or else (Nkind (Comp) in N_Unary_Op
3451 and then Check_Component (Right_Opnd (Comp)))
3453 or else (Nkind (Comp) = N_Selected_Component
3454 and then Check_Component (Prefix (Comp)));
3455 end Check_Component;
3457 -- Start of processing for Safe_Component
3460 -- If the component appears in an association that may
3461 -- correspond to more than one element, it is not analyzed
3462 -- before the expansion into assignments, to avoid side effects.
3463 -- We analyze, but do not resolve the copy, to obtain sufficient
3464 -- entity information for the checks that follow. If component is
3465 -- overloaded we assume an unsafe function call.
3467 if not Analyzed (Comp) then
3468 if Is_Overloaded (Expr) then
3471 elsif Nkind (Expr) = N_Aggregate
3472 and then not Is_Others_Aggregate (Expr)
3476 elsif Nkind (Expr) = N_Allocator then
3477 -- For now, too complex to analyze.
3482 Comp := New_Copy_Tree (Expr);
3483 Set_Parent (Comp, Parent (Expr));
3487 if Nkind (Comp) = N_Aggregate then
3488 return Safe_Aggregate (Comp);
3490 return Check_Component (Comp);
3494 -- Start of processing for In_Place_Assign_OK
3497 if Present (Component_Associations (N)) then
3499 -- On assignment, sliding can take place, so we cannot do the
3500 -- assignment in place unless the bounds of the aggregate are
3501 -- statically equal to those of the target.
3503 -- If the aggregate is given by an others choice, the bounds
3504 -- are derived from the left-hand side, and the assignment is
3505 -- safe if the expression is.
3507 if Is_Others_Aggregate (N) then
3510 (Expression (First (Component_Associations (N))));
3513 Aggr_In := First_Index (Etype (N));
3514 Obj_In := First_Index (Etype (Name (Parent (N))));
3516 while Present (Aggr_In) loop
3517 Get_Index_Bounds (Aggr_In, Aggr_Lo, Aggr_Hi);
3518 Get_Index_Bounds (Obj_In, Obj_Lo, Obj_Hi);
3520 if not Compile_Time_Known_Value (Aggr_Lo)
3521 or else not Compile_Time_Known_Value (Aggr_Hi)
3522 or else not Compile_Time_Known_Value (Obj_Lo)
3523 or else not Compile_Time_Known_Value (Obj_Hi)
3524 or else Expr_Value (Aggr_Lo) /= Expr_Value (Obj_Lo)
3525 or else Expr_Value (Aggr_Hi) /= Expr_Value (Obj_Hi)
3530 Next_Index (Aggr_In);
3531 Next_Index (Obj_In);
3535 -- Now check the component values themselves.
3537 return Safe_Aggregate (N);
3538 end In_Place_Assign_OK;
3544 function Must_Slide (N : Node_Id; Typ : Entity_Id) return Boolean
3546 Obj_Type : constant Entity_Id :=
3547 Etype (Defining_Identifier (Parent (N)));
3549 L1, L2, H1, H2 : Node_Id;
3552 -- No sliding if the type of the object is not established yet, if
3553 -- it is an unconstrained type whose actual subtype comes from the
3554 -- aggregate, or if the two types are identical.
3556 if not Is_Array_Type (Obj_Type) then
3559 elsif not Is_Constrained (Obj_Type) then
3562 elsif Typ = Obj_Type then
3566 -- Sliding can only occur along the first dimension
3568 Get_Index_Bounds (First_Index (Typ), L1, H1);
3569 Get_Index_Bounds (First_Index (Obj_Type), L2, H2);
3571 if not Is_Static_Expression (L1)
3572 or else not Is_Static_Expression (L2)
3573 or else not Is_Static_Expression (H1)
3574 or else not Is_Static_Expression (H2)
3578 return Expr_Value (L1) /= Expr_Value (L2)
3579 or else Expr_Value (H1) /= Expr_Value (H2);
3588 procedure Others_Check (Sub_Aggr : Node_Id; Dim : Pos) is
3589 Aggr_Lo : constant Node_Id := Aggr_Low (Dim);
3590 Aggr_Hi : constant Node_Id := Aggr_High (Dim);
3591 -- The bounds of the aggregate for this dimension.
3593 Ind_Typ : constant Entity_Id := Aggr_Index_Typ (Dim);
3594 -- The index type for this dimension.
3596 Need_To_Check : Boolean := False;
3598 Choices_Lo : Node_Id := Empty;
3599 Choices_Hi : Node_Id := Empty;
3600 -- The lowest and highest discrete choices for a named sub-aggregate
3602 Nb_Choices : Int := -1;
3603 -- The number of discrete non-others choices in this sub-aggregate
3605 Nb_Elements : Uint := Uint_0;
3606 -- The number of elements in a positional aggregate
3608 Cond : Node_Id := Empty;
3615 -- Check if we have an others choice. If we do make sure that this
3616 -- sub-aggregate contains at least one element in addition to the
3619 if Range_Checks_Suppressed (Ind_Typ) then
3620 Need_To_Check := False;
3622 elsif Present (Expressions (Sub_Aggr))
3623 and then Present (Component_Associations (Sub_Aggr))
3625 Need_To_Check := True;
3627 elsif Present (Component_Associations (Sub_Aggr)) then
3628 Assoc := Last (Component_Associations (Sub_Aggr));
3630 if Nkind (First (Choices (Assoc))) /= N_Others_Choice then
3631 Need_To_Check := False;
3634 -- Count the number of discrete choices. Start with -1
3635 -- because the others choice does not count.
3638 Assoc := First (Component_Associations (Sub_Aggr));
3639 while Present (Assoc) loop
3640 Choice := First (Choices (Assoc));
3641 while Present (Choice) loop
3642 Nb_Choices := Nb_Choices + 1;
3649 -- If there is only an others choice nothing to do
3651 Need_To_Check := (Nb_Choices > 0);
3655 Need_To_Check := False;
3658 -- If we are dealing with a positional sub-aggregate with an
3659 -- others choice then compute the number or positional elements.
3661 if Need_To_Check and then Present (Expressions (Sub_Aggr)) then
3662 Expr := First (Expressions (Sub_Aggr));
3663 Nb_Elements := Uint_0;
3664 while Present (Expr) loop
3665 Nb_Elements := Nb_Elements + 1;
3669 -- If the aggregate contains discrete choices and an others choice
3670 -- compute the smallest and largest discrete choice values.
3672 elsif Need_To_Check then
3673 Compute_Choices_Lo_And_Choices_Hi : declare
3675 Table : Case_Table_Type (1 .. Nb_Choices);
3676 -- Used to sort all the different choice values
3683 Assoc := First (Component_Associations (Sub_Aggr));
3684 while Present (Assoc) loop
3685 Choice := First (Choices (Assoc));
3686 while Present (Choice) loop
3687 if Nkind (Choice) = N_Others_Choice then
3691 Get_Index_Bounds (Choice, Low, High);
3692 Table (J).Choice_Lo := Low;
3693 Table (J).Choice_Hi := High;
3702 -- Sort the discrete choices
3704 Sort_Case_Table (Table);
3706 Choices_Lo := Table (1).Choice_Lo;
3707 Choices_Hi := Table (Nb_Choices).Choice_Hi;
3708 end Compute_Choices_Lo_And_Choices_Hi;
3711 -- If no others choice in this sub-aggregate, or the aggregate
3712 -- comprises only an others choice, nothing to do.
3714 if not Need_To_Check then
3717 -- If we are dealing with an aggregate containing an others
3718 -- choice and positional components, we generate the following test:
3720 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
3721 -- Ind_Typ'Pos (Aggr_Hi)
3723 -- raise Constraint_Error;
3726 elsif Nb_Elements > Uint_0 then
3732 Make_Attribute_Reference (Loc,
3733 Prefix => New_Reference_To (Ind_Typ, Loc),
3734 Attribute_Name => Name_Pos,
3737 (Duplicate_Subexpr_Move_Checks (Aggr_Lo))),
3738 Right_Opnd => Make_Integer_Literal (Loc, Nb_Elements - 1)),
3741 Make_Attribute_Reference (Loc,
3742 Prefix => New_Reference_To (Ind_Typ, Loc),
3743 Attribute_Name => Name_Pos,
3744 Expressions => New_List (
3745 Duplicate_Subexpr_Move_Checks (Aggr_Hi))));
3747 -- If we are dealing with an aggregate containing an others
3748 -- choice and discrete choices we generate the following test:
3750 -- [constraint_error when
3751 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
3759 Duplicate_Subexpr_Move_Checks (Choices_Lo),
3761 Duplicate_Subexpr_Move_Checks (Aggr_Lo)),
3766 Duplicate_Subexpr (Choices_Hi),
3768 Duplicate_Subexpr (Aggr_Hi)));
3771 if Present (Cond) then
3773 Make_Raise_Constraint_Error (Loc,
3775 Reason => CE_Length_Check_Failed));
3778 -- Now look inside the sub-aggregate to see if there is more work
3780 if Dim < Aggr_Dimension then
3782 -- Process positional components
3784 if Present (Expressions (Sub_Aggr)) then
3785 Expr := First (Expressions (Sub_Aggr));
3786 while Present (Expr) loop
3787 Others_Check (Expr, Dim + 1);
3792 -- Process component associations
3794 if Present (Component_Associations (Sub_Aggr)) then
3795 Assoc := First (Component_Associations (Sub_Aggr));
3796 while Present (Assoc) loop
3797 Expr := Expression (Assoc);
3798 Others_Check (Expr, Dim + 1);
3805 -- Remaining Expand_Array_Aggregate variables
3808 -- Holds the temporary aggregate value
3811 -- Holds the declaration of Tmp
3813 Aggr_Code : List_Id;
3814 Parent_Node : Node_Id;
3815 Parent_Kind : Node_Kind;
3817 -- Start of processing for Expand_Array_Aggregate
3820 -- Do not touch the special aggregates of attributes used for Asm calls
3822 if Is_RTE (Ctyp, RE_Asm_Input_Operand)
3823 or else Is_RTE (Ctyp, RE_Asm_Output_Operand)
3828 -- If the semantic analyzer has determined that aggregate N will raise
3829 -- Constraint_Error at run-time, then the aggregate node has been
3830 -- replaced with an N_Raise_Constraint_Error node and we should
3833 pragma Assert (not Raises_Constraint_Error (N));
3837 -- Check that the index range defined by aggregate bounds is
3838 -- compatible with corresponding index subtype.
3840 Index_Compatibility_Check : declare
3841 Aggr_Index_Range : Node_Id := First_Index (Typ);
3842 -- The current aggregate index range
3844 Index_Constraint : Node_Id := First_Index (Etype (Typ));
3845 -- The corresponding index constraint against which we have to
3846 -- check the above aggregate index range.
3849 Compute_Others_Present (N, 1);
3851 for J in 1 .. Aggr_Dimension loop
3852 -- There is no need to emit a check if an others choice is
3853 -- present for this array aggregate dimension since in this
3854 -- case one of N's sub-aggregates has taken its bounds from the
3855 -- context and these bounds must have been checked already. In
3856 -- addition all sub-aggregates corresponding to the same
3857 -- dimension must all have the same bounds (checked in (c) below).
3859 if not Range_Checks_Suppressed (Etype (Index_Constraint))
3860 and then not Others_Present (J)
3862 -- We don't use Checks.Apply_Range_Check here because it
3863 -- emits a spurious check. Namely it checks that the range
3864 -- defined by the aggregate bounds is non empty. But we know
3865 -- this already if we get here.
3867 Check_Bounds (Aggr_Index_Range, Index_Constraint);
3870 -- Save the low and high bounds of the aggregate index as well
3871 -- as the index type for later use in checks (b) and (c) below.
3873 Aggr_Low (J) := Low_Bound (Aggr_Index_Range);
3874 Aggr_High (J) := High_Bound (Aggr_Index_Range);
3876 Aggr_Index_Typ (J) := Etype (Index_Constraint);
3878 Next_Index (Aggr_Index_Range);
3879 Next_Index (Index_Constraint);
3881 end Index_Compatibility_Check;
3885 -- If an others choice is present check that no aggregate
3886 -- index is outside the bounds of the index constraint.
3888 Others_Check (N, 1);
3892 -- For multidimensional arrays make sure that all subaggregates
3893 -- corresponding to the same dimension have the same bounds.
3895 if Aggr_Dimension > 1 then
3896 Check_Same_Aggr_Bounds (N, 1);
3901 -- Here we test for is packed array aggregate that we can handle
3902 -- at compile time. If so, return with transformation done. Note
3903 -- that we do this even if the aggregate is nested, because once
3904 -- we have done this processing, there is no more nested aggregate!
3906 if Packed_Array_Aggregate_Handled (N) then
3910 -- At this point we try to convert to positional form
3912 Convert_To_Positional (N);
3914 -- if the result is no longer an aggregate (e.g. it may be a string
3915 -- literal, or a temporary which has the needed value), then we are
3916 -- done, since there is no longer a nested aggregate.
3918 if Nkind (N) /= N_Aggregate then
3921 -- We are also done if the result is an analyzed aggregate
3922 -- This case could use more comments ???
3925 and then N /= Original_Node (N)
3930 -- Now see if back end processing is possible
3932 if Backend_Processing_Possible (N) then
3934 -- If the aggregate is static but the constraints are not, build
3935 -- a static subtype for the aggregate, so that Gigi can place it
3936 -- in static memory. Perform an unchecked_conversion to the non-
3937 -- static type imposed by the context.
3940 Itype : constant Entity_Id := Etype (N);
3942 Needs_Type : Boolean := False;
3945 Index := First_Index (Itype);
3947 while Present (Index) loop
3948 if not Is_Static_Subtype (Etype (Index)) then
3957 Build_Constrained_Type (Positional => True);
3958 Rewrite (N, Unchecked_Convert_To (Itype, N));
3968 -- Delay expansion for nested aggregates it will be taken care of
3969 -- when the parent aggregate is expanded
3971 Parent_Node := Parent (N);
3972 Parent_Kind := Nkind (Parent_Node);
3974 if Parent_Kind = N_Qualified_Expression then
3975 Parent_Node := Parent (Parent_Node);
3976 Parent_Kind := Nkind (Parent_Node);
3979 if Parent_Kind = N_Aggregate
3980 or else Parent_Kind = N_Extension_Aggregate
3981 or else Parent_Kind = N_Component_Association
3982 or else (Parent_Kind = N_Object_Declaration
3983 and then Controlled_Type (Typ))
3984 or else (Parent_Kind = N_Assignment_Statement
3985 and then Inside_Init_Proc)
3987 Set_Expansion_Delayed (N);
3993 -- Look if in place aggregate expansion is possible
3995 -- For object declarations we build the aggregate in place, unless
3996 -- the array is bit-packed or the component is controlled.
3998 -- For assignments we do the assignment in place if all the component
3999 -- associations have compile-time known values. For other cases we
4000 -- create a temporary. The analysis for safety of on-line assignment
4001 -- is delicate, i.e. we don't know how to do it fully yet ???
4003 if Requires_Transient_Scope (Typ) then
4004 Establish_Transient_Scope
4005 (N, Sec_Stack => Has_Controlled_Component (Typ));
4008 if Has_Default_Init_Comps (N) then
4009 Maybe_In_Place_OK := False;
4011 Maybe_In_Place_OK :=
4012 Comes_From_Source (N)
4013 and then Nkind (Parent (N)) = N_Assignment_Statement
4014 and then not Is_Bit_Packed_Array (Typ)
4015 and then not Has_Controlled_Component (Typ)
4016 and then In_Place_Assign_OK;
4019 if not Has_Default_Init_Comps (N)
4020 and then Comes_From_Source (Parent (N))
4021 and then Nkind (Parent (N)) = N_Object_Declaration
4022 and then not Must_Slide (N, Typ)
4023 and then N = Expression (Parent (N))
4024 and then not Is_Bit_Packed_Array (Typ)
4025 and then not Has_Controlled_Component (Typ)
4026 and then not Has_Address_Clause (Parent (N))
4028 Tmp := Defining_Identifier (Parent (N));
4029 Set_No_Initialization (Parent (N));
4030 Set_Expression (Parent (N), Empty);
4032 -- Set the type of the entity, for use in the analysis of the
4033 -- subsequent indexed assignments. If the nominal type is not
4034 -- constrained, build a subtype from the known bounds of the
4035 -- aggregate. If the declaration has a subtype mark, use it,
4036 -- otherwise use the itype of the aggregate.
4038 if not Is_Constrained (Typ) then
4039 Build_Constrained_Type (Positional => False);
4040 elsif Is_Entity_Name (Object_Definition (Parent (N)))
4041 and then Is_Constrained (Entity (Object_Definition (Parent (N))))
4043 Set_Etype (Tmp, Entity (Object_Definition (Parent (N))));
4045 Set_Size_Known_At_Compile_Time (Typ, False);
4046 Set_Etype (Tmp, Typ);
4049 elsif Maybe_In_Place_OK
4050 and then Is_Entity_Name (Name (Parent (N)))
4052 Tmp := Entity (Name (Parent (N)));
4054 if Etype (Tmp) /= Etype (N) then
4055 Apply_Length_Check (N, Etype (Tmp));
4057 if Nkind (N) = N_Raise_Constraint_Error then
4059 -- Static error, nothing further to expand
4065 elsif Maybe_In_Place_OK
4066 and then Nkind (Name (Parent (N))) = N_Explicit_Dereference
4067 and then Is_Entity_Name (Prefix (Name (Parent (N))))
4069 Tmp := Name (Parent (N));
4071 if Etype (Tmp) /= Etype (N) then
4072 Apply_Length_Check (N, Etype (Tmp));
4075 elsif Maybe_In_Place_OK
4076 and then Nkind (Name (Parent (N))) = N_Slice
4077 and then Safe_Slice_Assignment (N)
4079 -- Safe_Slice_Assignment rewrites assignment as a loop
4085 -- In place aggregate expansion is not possible
4088 Maybe_In_Place_OK := False;
4089 Tmp := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4091 Make_Object_Declaration
4093 Defining_Identifier => Tmp,
4094 Object_Definition => New_Occurrence_Of (Typ, Loc));
4095 Set_No_Initialization (Tmp_Decl, True);
4097 -- If we are within a loop, the temporary will be pushed on the
4098 -- stack at each iteration. If the aggregate is the expression for
4099 -- an allocator, it will be immediately copied to the heap and can
4100 -- be reclaimed at once. We create a transient scope around the
4101 -- aggregate for this purpose.
4103 if Ekind (Current_Scope) = E_Loop
4104 and then Nkind (Parent (Parent (N))) = N_Allocator
4106 Establish_Transient_Scope (N, False);
4109 Insert_Action (N, Tmp_Decl);
4112 -- Construct and insert the aggregate code. We can safely suppress
4113 -- index checks because this code is guaranteed not to raise CE
4114 -- on index checks. However we should *not* suppress all checks.
4120 if Nkind (Tmp) = N_Defining_Identifier then
4121 Target := New_Reference_To (Tmp, Loc);
4125 if Has_Default_Init_Comps (N) then
4127 -- Ada 2005 (AI-287): This case has not been analyzed???
4129 raise Program_Error;
4132 -- Name in assignment is explicit dereference
4134 Target := New_Copy (Tmp);
4138 Build_Array_Aggr_Code (N,
4140 Index => First_Index (Typ),
4142 Scalar_Comp => Is_Scalar_Type (Ctyp));
4145 if Comes_From_Source (Tmp) then
4146 Insert_Actions_After (Parent (N), Aggr_Code);
4149 Insert_Actions (N, Aggr_Code);
4152 -- If the aggregate has been assigned in place, remove the original
4155 if Nkind (Parent (N)) = N_Assignment_Statement
4156 and then Maybe_In_Place_OK
4158 Rewrite (Parent (N), Make_Null_Statement (Loc));
4160 elsif Nkind (Parent (N)) /= N_Object_Declaration
4161 or else Tmp /= Defining_Identifier (Parent (N))
4163 Rewrite (N, New_Occurrence_Of (Tmp, Loc));
4164 Analyze_And_Resolve (N, Typ);
4166 end Expand_Array_Aggregate;
4168 ------------------------
4169 -- Expand_N_Aggregate --
4170 ------------------------
4172 procedure Expand_N_Aggregate (N : Node_Id) is
4174 if Is_Record_Type (Etype (N)) then
4175 Expand_Record_Aggregate (N);
4177 Expand_Array_Aggregate (N);
4181 when RE_Not_Available =>
4183 end Expand_N_Aggregate;
4185 ----------------------------------
4186 -- Expand_N_Extension_Aggregate --
4187 ----------------------------------
4189 -- If the ancestor part is an expression, add a component association for
4190 -- the parent field. If the type of the ancestor part is not the direct
4191 -- parent of the expected type, build recursively the needed ancestors.
4192 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
4193 -- ration for a temporary of the expected type, followed by individual
4194 -- assignments to the given components.
4196 procedure Expand_N_Extension_Aggregate (N : Node_Id) is
4197 Loc : constant Source_Ptr := Sloc (N);
4198 A : constant Node_Id := Ancestor_Part (N);
4199 Typ : constant Entity_Id := Etype (N);
4202 -- If the ancestor is a subtype mark, an init proc must be called
4203 -- on the resulting object which thus has to be materialized in
4206 if Is_Entity_Name (A) and then Is_Type (Entity (A)) then
4207 Convert_To_Assignments (N, Typ);
4209 -- The extension aggregate is transformed into a record aggregate
4210 -- of the following form (c1 and c2 are inherited components)
4212 -- (Exp with c3 => a, c4 => b)
4213 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c1 => a, c2 => b)
4218 -- No tag is needed in the case of Java_VM
4221 Expand_Record_Aggregate (N,
4224 Expand_Record_Aggregate (N,
4225 Orig_Tag => New_Occurrence_Of (Access_Disp_Table (Typ), Loc),
4231 when RE_Not_Available =>
4233 end Expand_N_Extension_Aggregate;
4235 -----------------------------
4236 -- Expand_Record_Aggregate --
4237 -----------------------------
4239 procedure Expand_Record_Aggregate
4241 Orig_Tag : Node_Id := Empty;
4242 Parent_Expr : Node_Id := Empty)
4244 Loc : constant Source_Ptr := Sloc (N);
4245 Comps : constant List_Id := Component_Associations (N);
4246 Typ : constant Entity_Id := Etype (N);
4247 Base_Typ : constant Entity_Id := Base_Type (Typ);
4249 function Has_Delayed_Nested_Aggregate_Or_Tagged_Comps return Boolean;
4250 -- Checks the presence of a nested aggregate which needs Late_Expansion
4251 -- or the presence of tagged components which may need tag adjustment.
4253 --------------------------------------------------
4254 -- Has_Delayed_Nested_Aggregate_Or_Tagged_Comps --
4255 --------------------------------------------------
4257 function Has_Delayed_Nested_Aggregate_Or_Tagged_Comps return Boolean is
4267 while Present (C) loop
4268 if Nkind (Expression (C)) = N_Qualified_Expression then
4269 Expr_Q := Expression (Expression (C));
4271 Expr_Q := Expression (C);
4274 -- Return true if the aggregate has any associations for
4275 -- tagged components that may require tag adjustment.
4276 -- These are cases where the source expression may have
4277 -- a tag that could differ from the component tag (e.g.,
4278 -- can occur for type conversions and formal parameters).
4279 -- (Tag adjustment is not needed if Java_VM because object
4280 -- tags are implicit in the JVM.)
4282 if Is_Tagged_Type (Etype (Expr_Q))
4283 and then (Nkind (Expr_Q) = N_Type_Conversion
4284 or else (Is_Entity_Name (Expr_Q)
4285 and then Ekind (Entity (Expr_Q)) in Formal_Kind))
4286 and then not Java_VM
4291 if Is_Delayed_Aggregate (Expr_Q) then
4299 end Has_Delayed_Nested_Aggregate_Or_Tagged_Comps;
4301 -- Remaining Expand_Record_Aggregate variables
4303 Tag_Value : Node_Id;
4307 -- Start of processing for Expand_Record_Aggregate
4310 -- If the aggregate is to be assigned to an atomic variable, we
4311 -- have to prevent a piecemeal assignment even if the aggregate
4312 -- is to be expanded. We create a temporary for the aggregate, and
4313 -- assign the temporary instead, so that the back end can generate
4314 -- an atomic move for it.
4317 and then (Nkind (Parent (N)) = N_Object_Declaration
4318 or else Nkind (Parent (N)) = N_Assignment_Statement)
4319 and then Comes_From_Source (Parent (N))
4321 Expand_Atomic_Aggregate (N, Typ);
4325 -- Gigi doesn't handle properly temporaries of variable size
4326 -- so we generate it in the front-end
4328 if not Size_Known_At_Compile_Time (Typ) then
4329 Convert_To_Assignments (N, Typ);
4331 -- Temporaries for controlled aggregates need to be attached to a
4332 -- final chain in order to be properly finalized, so it has to
4333 -- be created in the front-end
4335 elsif Is_Controlled (Typ)
4336 or else Has_Controlled_Component (Base_Type (Typ))
4338 Convert_To_Assignments (N, Typ);
4340 -- Ada 2005 (AI-287): In case of default initialized components we
4341 -- convert the aggregate into assignments.
4343 elsif Has_Default_Init_Comps (N) then
4344 Convert_To_Assignments (N, Typ);
4346 elsif Has_Delayed_Nested_Aggregate_Or_Tagged_Comps then
4347 Convert_To_Assignments (N, Typ);
4349 -- If an ancestor is private, some components are not inherited and
4350 -- we cannot expand into a record aggregate
4352 elsif Has_Private_Ancestor (Typ) then
4353 Convert_To_Assignments (N, Typ);
4355 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
4356 -- is not able to handle the aggregate for Late_Request.
4358 elsif Is_Tagged_Type (Typ) and then Has_Discriminants (Typ) then
4359 Convert_To_Assignments (N, Typ);
4361 -- If some components are mutable, the size of the aggregate component
4362 -- may be disctinct from the default size of the type component, so
4363 -- we need to expand to insure that the back-end copies the proper
4364 -- size of the data.
4366 elsif Has_Mutable_Components (Typ) then
4367 Convert_To_Assignments (N, Typ);
4369 -- If the type involved has any non-bit aligned components, then
4370 -- we are not sure that the back end can handle this case correctly.
4372 elsif Type_May_Have_Bit_Aligned_Components (Typ) then
4373 Convert_To_Assignments (N, Typ);
4375 -- In all other cases we generate a proper aggregate that
4376 -- can be handled by gigi.
4379 -- If no discriminants, nothing special to do
4381 if not Has_Discriminants (Typ) then
4384 -- Case of discriminants present
4386 elsif Is_Derived_Type (Typ) then
4388 -- For untagged types, non-stored discriminants are replaced
4389 -- with stored discriminants, which are the ones that gigi uses
4390 -- to describe the type and its components.
4392 Generate_Aggregate_For_Derived_Type : declare
4393 Constraints : constant List_Id := New_List;
4394 First_Comp : Node_Id;
4395 Discriminant : Entity_Id;
4397 Num_Disc : Int := 0;
4398 Num_Gird : Int := 0;
4400 procedure Prepend_Stored_Values (T : Entity_Id);
4401 -- Scan the list of stored discriminants of the type, and
4402 -- add their values to the aggregate being built.
4404 ---------------------------
4405 -- Prepend_Stored_Values --
4406 ---------------------------
4408 procedure Prepend_Stored_Values (T : Entity_Id) is
4410 Discriminant := First_Stored_Discriminant (T);
4412 while Present (Discriminant) loop
4414 Make_Component_Association (Loc,
4416 New_List (New_Occurrence_Of (Discriminant, Loc)),
4420 Get_Discriminant_Value (
4423 Discriminant_Constraint (Typ))));
4425 if No (First_Comp) then
4426 Prepend_To (Component_Associations (N), New_Comp);
4428 Insert_After (First_Comp, New_Comp);
4431 First_Comp := New_Comp;
4432 Next_Stored_Discriminant (Discriminant);
4434 end Prepend_Stored_Values;
4436 -- Start of processing for Generate_Aggregate_For_Derived_Type
4439 -- Remove the associations for the discriminant of
4440 -- the derived type.
4442 First_Comp := First (Component_Associations (N));
4444 while Present (First_Comp) loop
4448 if Ekind (Entity (First (Choices (Comp)))) =
4452 Num_Disc := Num_Disc + 1;
4456 -- Insert stored discriminant associations in the correct
4457 -- order. If there are more stored discriminants than new
4458 -- discriminants, there is at least one new discriminant
4459 -- that constrains more than one of the stored discriminants.
4460 -- In this case we need to construct a proper subtype of
4461 -- the parent type, in order to supply values to all the
4462 -- components. Otherwise there is one-one correspondence
4463 -- between the constraints and the stored discriminants.
4465 First_Comp := Empty;
4467 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
4469 while Present (Discriminant) loop
4470 Num_Gird := Num_Gird + 1;
4471 Next_Stored_Discriminant (Discriminant);
4474 -- Case of more stored discriminants than new discriminants
4476 if Num_Gird > Num_Disc then
4478 -- Create a proper subtype of the parent type, which is
4479 -- the proper implementation type for the aggregate, and
4480 -- convert it to the intended target type.
4482 Discriminant := First_Stored_Discriminant (Base_Type (Typ));
4484 while Present (Discriminant) loop
4487 Get_Discriminant_Value (
4490 Discriminant_Constraint (Typ)));
4491 Append (New_Comp, Constraints);
4492 Next_Stored_Discriminant (Discriminant);
4496 Make_Subtype_Declaration (Loc,
4497 Defining_Identifier =>
4498 Make_Defining_Identifier (Loc,
4499 New_Internal_Name ('T')),
4500 Subtype_Indication =>
4501 Make_Subtype_Indication (Loc,
4503 New_Occurrence_Of (Etype (Base_Type (Typ)), Loc),
4505 Make_Index_Or_Discriminant_Constraint
4506 (Loc, Constraints)));
4508 Insert_Action (N, Decl);
4509 Prepend_Stored_Values (Base_Type (Typ));
4511 Set_Etype (N, Defining_Identifier (Decl));
4514 Rewrite (N, Unchecked_Convert_To (Typ, N));
4517 -- Case where we do not have fewer new discriminants than
4518 -- stored discriminants, so in this case we can simply
4519 -- use the stored discriminants of the subtype.
4522 Prepend_Stored_Values (Typ);
4524 end Generate_Aggregate_For_Derived_Type;
4527 if Is_Tagged_Type (Typ) then
4529 -- The tagged case, _parent and _tag component must be created.
4531 -- Reset null_present unconditionally. tagged records always have
4532 -- at least one field (the tag or the parent)
4534 Set_Null_Record_Present (N, False);
4536 -- When the current aggregate comes from the expansion of an
4537 -- extension aggregate, the parent expr is replaced by an
4538 -- aggregate formed by selected components of this expr
4540 if Present (Parent_Expr)
4541 and then Is_Empty_List (Comps)
4543 Comp := First_Entity (Typ);
4544 while Present (Comp) loop
4546 -- Skip all entities that aren't discriminants or components
4548 if Ekind (Comp) /= E_Discriminant
4549 and then Ekind (Comp) /= E_Component
4553 -- Skip all expander-generated components
4556 not Comes_From_Source (Original_Record_Component (Comp))
4562 Make_Selected_Component (Loc,
4564 Unchecked_Convert_To (Typ,
4565 Duplicate_Subexpr (Parent_Expr, True)),
4567 Selector_Name => New_Occurrence_Of (Comp, Loc));
4570 Make_Component_Association (Loc,
4572 New_List (New_Occurrence_Of (Comp, Loc)),
4576 Analyze_And_Resolve (New_Comp, Etype (Comp));
4583 -- Compute the value for the Tag now, if the type is a root it
4584 -- will be included in the aggregate right away, otherwise it will
4585 -- be propagated to the parent aggregate
4587 if Present (Orig_Tag) then
4588 Tag_Value := Orig_Tag;
4592 Tag_Value := New_Occurrence_Of (Access_Disp_Table (Typ), Loc);
4595 -- For a derived type, an aggregate for the parent is formed with
4596 -- all the inherited components.
4598 if Is_Derived_Type (Typ) then
4601 First_Comp : Node_Id;
4602 Parent_Comps : List_Id;
4603 Parent_Aggr : Node_Id;
4604 Parent_Name : Node_Id;
4607 -- Remove the inherited component association from the
4608 -- aggregate and store them in the parent aggregate
4610 First_Comp := First (Component_Associations (N));
4611 Parent_Comps := New_List;
4613 while Present (First_Comp)
4614 and then Scope (Original_Record_Component (
4615 Entity (First (Choices (First_Comp))))) /= Base_Typ
4620 Append (Comp, Parent_Comps);
4623 Parent_Aggr := Make_Aggregate (Loc,
4624 Component_Associations => Parent_Comps);
4625 Set_Etype (Parent_Aggr, Etype (Base_Type (Typ)));
4627 -- Find the _parent component
4629 Comp := First_Component (Typ);
4630 while Chars (Comp) /= Name_uParent loop
4631 Comp := Next_Component (Comp);
4634 Parent_Name := New_Occurrence_Of (Comp, Loc);
4636 -- Insert the parent aggregate
4638 Prepend_To (Component_Associations (N),
4639 Make_Component_Association (Loc,
4640 Choices => New_List (Parent_Name),
4641 Expression => Parent_Aggr));
4643 -- Expand recursively the parent propagating the right Tag
4645 Expand_Record_Aggregate (
4646 Parent_Aggr, Tag_Value, Parent_Expr);
4649 -- For a root type, the tag component is added (unless compiling
4650 -- for the Java VM, where tags are implicit).
4652 elsif not Java_VM then
4654 Tag_Name : constant Node_Id :=
4655 New_Occurrence_Of (Tag_Component (Typ), Loc);
4656 Typ_Tag : constant Entity_Id := RTE (RE_Tag);
4657 Conv_Node : constant Node_Id :=
4658 Unchecked_Convert_To (Typ_Tag, Tag_Value);
4661 Set_Etype (Conv_Node, Typ_Tag);
4662 Prepend_To (Component_Associations (N),
4663 Make_Component_Association (Loc,
4664 Choices => New_List (Tag_Name),
4665 Expression => Conv_Node));
4670 end Expand_Record_Aggregate;
4672 ----------------------------
4673 -- Has_Default_Init_Comps --
4674 ----------------------------
4676 function Has_Default_Init_Comps (N : Node_Id) return Boolean is
4677 Comps : constant List_Id := Component_Associations (N);
4681 pragma Assert (Nkind (N) = N_Aggregate
4682 or else Nkind (N) = N_Extension_Aggregate);
4688 -- Check if any direct component has default initialized components
4691 while Present (C) loop
4692 if Box_Present (C) then
4699 -- Recursive call in case of aggregate expression
4702 while Present (C) loop
4703 Expr := Expression (C);
4706 and then (Nkind (Expr) = N_Aggregate
4707 or else Nkind (Expr) = N_Extension_Aggregate)
4708 and then Has_Default_Init_Comps (Expr)
4717 end Has_Default_Init_Comps;
4719 --------------------------
4720 -- Is_Delayed_Aggregate --
4721 --------------------------
4723 function Is_Delayed_Aggregate (N : Node_Id) return Boolean is
4724 Node : Node_Id := N;
4725 Kind : Node_Kind := Nkind (Node);
4728 if Kind = N_Qualified_Expression then
4729 Node := Expression (Node);
4730 Kind := Nkind (Node);
4733 if Kind /= N_Aggregate and then Kind /= N_Extension_Aggregate then
4736 return Expansion_Delayed (Node);
4738 end Is_Delayed_Aggregate;
4740 --------------------
4741 -- Late_Expansion --
4742 --------------------
4744 function Late_Expansion
4748 Flist : Node_Id := Empty;
4749 Obj : Entity_Id := Empty) return List_Id
4752 if Is_Record_Type (Etype (N)) then
4753 return Build_Record_Aggr_Code (N, Typ, Target, Flist, Obj);
4755 else pragma Assert (Is_Array_Type (Etype (N)));
4757 Build_Array_Aggr_Code
4759 Ctype => Component_Type (Etype (N)),
4760 Index => First_Index (Typ),
4762 Scalar_Comp => Is_Scalar_Type (Component_Type (Typ)),
4768 ----------------------------------
4769 -- Make_OK_Assignment_Statement --
4770 ----------------------------------
4772 function Make_OK_Assignment_Statement
4775 Expression : Node_Id) return Node_Id
4778 Set_Assignment_OK (Name);
4779 return Make_Assignment_Statement (Sloc, Name, Expression);
4780 end Make_OK_Assignment_Statement;
4782 -----------------------
4783 -- Number_Of_Choices --
4784 -----------------------
4786 function Number_Of_Choices (N : Node_Id) return Nat is
4790 Nb_Choices : Nat := 0;
4793 if Present (Expressions (N)) then
4797 Assoc := First (Component_Associations (N));
4798 while Present (Assoc) loop
4800 Choice := First (Choices (Assoc));
4801 while Present (Choice) loop
4803 if Nkind (Choice) /= N_Others_Choice then
4804 Nb_Choices := Nb_Choices + 1;
4814 end Number_Of_Choices;
4816 ------------------------------------
4817 -- Packed_Array_Aggregate_Handled --
4818 ------------------------------------
4820 -- The current version of this procedure will handle at compile time
4821 -- any array aggregate that meets these conditions:
4823 -- One dimensional, bit packed
4824 -- Underlying packed type is modular type
4825 -- Bounds are within 32-bit Int range
4826 -- All bounds and values are static
4828 function Packed_Array_Aggregate_Handled (N : Node_Id) return Boolean is
4829 Loc : constant Source_Ptr := Sloc (N);
4830 Typ : constant Entity_Id := Etype (N);
4831 Ctyp : constant Entity_Id := Component_Type (Typ);
4833 Not_Handled : exception;
4834 -- Exception raised if this aggregate cannot be handled
4837 -- For now, handle only one dimensional bit packed arrays
4839 if not Is_Bit_Packed_Array (Typ)
4840 or else Number_Dimensions (Typ) > 1
4841 or else not Is_Modular_Integer_Type (Packed_Array_Type (Typ))
4847 Csiz : constant Nat := UI_To_Int (Component_Size (Typ));
4851 -- Bounds of index type
4855 -- Values of bounds if compile time known
4857 function Get_Component_Val (N : Node_Id) return Uint;
4858 -- Given a expression value N of the component type Ctyp, returns
4859 -- A value of Csiz (component size) bits representing this value.
4860 -- If the value is non-static or any other reason exists why the
4861 -- value cannot be returned, then Not_Handled is raised.
4863 -----------------------
4864 -- Get_Component_Val --
4865 -----------------------
4867 function Get_Component_Val (N : Node_Id) return Uint is
4871 -- We have to analyze the expression here before doing any further
4872 -- processing here. The analysis of such expressions is deferred
4873 -- till expansion to prevent some problems of premature analysis.
4875 Analyze_And_Resolve (N, Ctyp);
4877 -- Must have a compile time value. String literals have to
4878 -- be converted into temporaries as well, because they cannot
4879 -- easily be converted into their bit representation.
4881 if not Compile_Time_Known_Value (N)
4882 or else Nkind (N) = N_String_Literal
4887 Val := Expr_Rep_Value (N);
4889 -- Adjust for bias, and strip proper number of bits
4891 if Has_Biased_Representation (Ctyp) then
4892 Val := Val - Expr_Value (Type_Low_Bound (Ctyp));
4895 return Val mod Uint_2 ** Csiz;
4896 end Get_Component_Val;
4898 -- Here we know we have a one dimensional bit packed array
4901 Get_Index_Bounds (First_Index (Typ), Lo, Hi);
4903 -- Cannot do anything if bounds are dynamic
4905 if not Compile_Time_Known_Value (Lo)
4907 not Compile_Time_Known_Value (Hi)
4912 -- Or are silly out of range of int bounds
4914 Lob := Expr_Value (Lo);
4915 Hib := Expr_Value (Hi);
4917 if not UI_Is_In_Int_Range (Lob)
4919 not UI_Is_In_Int_Range (Hib)
4924 -- At this stage we have a suitable aggregate for handling
4925 -- at compile time (the only remaining checks, are that the
4926 -- values of expressions in the aggregate are compile time
4927 -- known (check performed by Get_Component_Val), and that
4928 -- any subtypes or ranges are statically known.
4930 -- If the aggregate is not fully positional at this stage,
4931 -- then convert it to positional form. Either this will fail,
4932 -- in which case we can do nothing, or it will succeed, in
4933 -- which case we have succeeded in handling the aggregate,
4934 -- or it will stay an aggregate, in which case we have failed
4935 -- to handle this case.
4937 if Present (Component_Associations (N)) then
4938 Convert_To_Positional
4939 (N, Max_Others_Replicate => 64, Handle_Bit_Packed => True);
4940 return Nkind (N) /= N_Aggregate;
4943 -- Otherwise we are all positional, so convert to proper value
4946 Lov : constant Nat := UI_To_Int (Lob);
4947 Hiv : constant Nat := UI_To_Int (Hib);
4949 Len : constant Nat := Int'Max (0, Hiv - Lov + 1);
4950 -- The length of the array (number of elements)
4952 Aggregate_Val : Uint;
4953 -- Value of aggregate. The value is set in the low order
4954 -- bits of this value. For the little-endian case, the
4955 -- values are stored from low-order to high-order and
4956 -- for the big-endian case the values are stored from
4957 -- high-order to low-order. Note that gigi will take care
4958 -- of the conversions to left justify the value in the big
4959 -- endian case (because of left justified modular type
4960 -- processing), so we do not have to worry about that here.
4963 -- Integer literal for resulting constructed value
4966 -- Shift count from low order for next value
4969 -- Shift increment for loop
4972 -- Next expression from positional parameters of aggregate
4975 -- For little endian, we fill up the low order bits of the
4976 -- target value. For big endian we fill up the high order
4977 -- bits of the target value (which is a left justified
4980 if Bytes_Big_Endian xor Debug_Flag_8 then
4981 Shift := Csiz * (Len - 1);
4988 -- Loop to set the values
4991 Aggregate_Val := Uint_0;
4993 Expr := First (Expressions (N));
4994 Aggregate_Val := Get_Component_Val (Expr) * Uint_2 ** Shift;
4996 for J in 2 .. Len loop
4997 Shift := Shift + Incr;
5000 Aggregate_Val + Get_Component_Val (Expr) * Uint_2 ** Shift;
5004 -- Now we can rewrite with the proper value
5007 Make_Integer_Literal (Loc,
5008 Intval => Aggregate_Val);
5009 Set_Print_In_Hex (Lit);
5011 -- Construct the expression using this literal. Note that it is
5012 -- important to qualify the literal with its proper modular type
5013 -- since universal integer does not have the required range and
5014 -- also this is a left justified modular type, which is important
5015 -- in the big-endian case.
5018 Unchecked_Convert_To (Typ,
5019 Make_Qualified_Expression (Loc,
5021 New_Occurrence_Of (Packed_Array_Type (Typ), Loc),
5022 Expression => Lit)));
5024 Analyze_And_Resolve (N, Typ);
5032 end Packed_Array_Aggregate_Handled;
5034 ----------------------------
5035 -- Has_Mutable_Components --
5036 ----------------------------
5038 function Has_Mutable_Components (Typ : Entity_Id) return Boolean is
5042 Comp := First_Component (Typ);
5044 while Present (Comp) loop
5045 if Is_Record_Type (Etype (Comp))
5046 and then Has_Discriminants (Etype (Comp))
5047 and then not Is_Constrained (Etype (Comp))
5052 Next_Component (Comp);
5056 end Has_Mutable_Components;
5058 ------------------------------
5059 -- Initialize_Discriminants --
5060 ------------------------------
5062 procedure Initialize_Discriminants (N : Node_Id; Typ : Entity_Id) is
5063 Loc : constant Source_Ptr := Sloc (N);
5064 Bas : constant Entity_Id := Base_Type (Typ);
5065 Par : constant Entity_Id := Etype (Bas);
5066 Decl : constant Node_Id := Parent (Par);
5070 if Is_Tagged_Type (Bas)
5071 and then Is_Derived_Type (Bas)
5072 and then Has_Discriminants (Par)
5073 and then Has_Discriminants (Bas)
5074 and then Number_Discriminants (Bas) /= Number_Discriminants (Par)
5075 and then Nkind (Decl) = N_Full_Type_Declaration
5076 and then Nkind (Type_Definition (Decl)) = N_Record_Definition
5078 (Variant_Part (Component_List (Type_Definition (Decl))))
5079 and then Nkind (N) /= N_Extension_Aggregate
5082 -- Call init proc to set discriminants.
5083 -- There should eventually be a special procedure for this ???
5085 Ref := New_Reference_To (Defining_Identifier (N), Loc);
5086 Insert_Actions_After (N,
5087 Build_Initialization_Call (Sloc (N), Ref, Typ));
5089 end Initialize_Discriminants;
5091 ---------------------------
5092 -- Safe_Slice_Assignment --
5093 ---------------------------
5095 function Safe_Slice_Assignment (N : Node_Id) return Boolean is
5096 Loc : constant Source_Ptr := Sloc (Parent (N));
5097 Pref : constant Node_Id := Prefix (Name (Parent (N)));
5098 Range_Node : constant Node_Id := Discrete_Range (Name (Parent (N)));
5106 -- Generate: for J in Range loop Pref (J) := Expr; end loop;
5108 if Comes_From_Source (N)
5109 and then No (Expressions (N))
5110 and then Nkind (First (Choices (First (Component_Associations (N)))))
5114 Expression (First (Component_Associations (N)));
5115 L_J := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
5118 Make_Iteration_Scheme (Loc,
5119 Loop_Parameter_Specification =>
5120 Make_Loop_Parameter_Specification
5122 Defining_Identifier => L_J,
5123 Discrete_Subtype_Definition => Relocate_Node (Range_Node)));
5126 Make_Assignment_Statement (Loc,
5128 Make_Indexed_Component (Loc,
5129 Prefix => Relocate_Node (Pref),
5130 Expressions => New_List (New_Occurrence_Of (L_J, Loc))),
5131 Expression => Relocate_Node (Expr));
5133 -- Construct the final loop
5136 Make_Implicit_Loop_Statement
5137 (Node => Parent (N),
5138 Identifier => Empty,
5139 Iteration_Scheme => L_Iter,
5140 Statements => New_List (L_Body));
5142 -- Set type of aggregate to be type of lhs in assignment,
5143 -- to suppress redundant length checks.
5145 Set_Etype (N, Etype (Name (Parent (N))));
5147 Rewrite (Parent (N), Stat);
5148 Analyze (Parent (N));
5154 end Safe_Slice_Assignment;
5156 ---------------------
5157 -- Sort_Case_Table --
5158 ---------------------
5160 procedure Sort_Case_Table (Case_Table : in out Case_Table_Type) is
5161 L : constant Int := Case_Table'First;
5162 U : constant Int := Case_Table'Last;
5171 T := Case_Table (K + 1);
5175 and then Expr_Value (Case_Table (J - 1).Choice_Lo) >
5176 Expr_Value (T.Choice_Lo)
5178 Case_Table (J) := Case_Table (J - 1);
5182 Case_Table (J) := T;
5185 end Sort_Case_Table;
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