1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Checks
; use Checks
;
28 with Debug
; use Debug
;
29 with Einfo
; use Einfo
;
30 with Elists
; use Elists
;
31 with Errout
; use Errout
;
32 with Expander
; use Expander
;
33 with Exp_Util
; use Exp_Util
;
34 with Exp_Ch3
; use Exp_Ch3
;
35 with Exp_Ch6
; use Exp_Ch6
;
36 with Exp_Ch7
; use Exp_Ch7
;
37 with Exp_Ch9
; use Exp_Ch9
;
38 with Exp_Disp
; use Exp_Disp
;
39 with Exp_Tss
; use Exp_Tss
;
40 with Fname
; use Fname
;
41 with Freeze
; use Freeze
;
42 with Itypes
; use Itypes
;
44 with Namet
; use Namet
;
45 with Nmake
; use Nmake
;
46 with Nlists
; use Nlists
;
48 with Restrict
; use Restrict
;
49 with Rident
; use Rident
;
50 with Rtsfind
; use Rtsfind
;
51 with Ttypes
; use Ttypes
;
53 with Sem_Aggr
; use Sem_Aggr
;
54 with Sem_Aux
; use Sem_Aux
;
55 with Sem_Ch3
; use Sem_Ch3
;
56 with Sem_Eval
; use Sem_Eval
;
57 with Sem_Res
; use Sem_Res
;
58 with Sem_Util
; use Sem_Util
;
59 with Sinfo
; use Sinfo
;
60 with Snames
; use Snames
;
61 with Stand
; use Stand
;
62 with Stringt
; use Stringt
;
63 with Targparm
; use Targparm
;
64 with Tbuild
; use Tbuild
;
65 with Uintp
; use Uintp
;
67 package body Exp_Aggr
is
69 type Case_Bounds
is record
72 Choice_Node
: Node_Id
;
75 type Case_Table_Type
is array (Nat
range <>) of Case_Bounds
;
76 -- Table type used by Check_Case_Choices procedure
78 procedure Collect_Initialization_Statements
81 Node_After
: Node_Id
);
82 -- If Obj is not frozen, collect actions inserted after N until, but not
83 -- including, Node_After, for initialization of Obj, and move them to an
84 -- expression with actions, which becomes the Initialization_Statements for
87 function Has_Default_Init_Comps
(N
: Node_Id
) return Boolean;
88 -- N is an aggregate (record or array). Checks the presence of default
89 -- initialization (<>) in any component (Ada 2005: AI-287).
91 function Is_Static_Dispatch_Table_Aggregate
(N
: Node_Id
) return Boolean;
92 -- Returns true if N is an aggregate used to initialize the components
93 -- of a statically allocated dispatch table.
96 (Obj_Type
: Entity_Id
;
97 Typ
: Entity_Id
) return Boolean;
98 -- A static array aggregate in an object declaration can in most cases be
99 -- expanded in place. The one exception is when the aggregate is given
100 -- with component associations that specify different bounds from those of
101 -- the type definition in the object declaration. In this pathological
102 -- case the aggregate must slide, and we must introduce an intermediate
103 -- temporary to hold it.
105 -- The same holds in an assignment to one-dimensional array of arrays,
106 -- when a component may be given with bounds that differ from those of the
109 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
);
110 -- Sort the Case Table using the Lower Bound of each Choice as the key.
111 -- A simple insertion sort is used since the number of choices in a case
112 -- statement of variant part will usually be small and probably in near
115 ------------------------------------------------------
116 -- Local subprograms for Record Aggregate Expansion --
117 ------------------------------------------------------
119 function Build_Record_Aggr_Code
122 Lhs
: Node_Id
) return List_Id
;
123 -- N is an N_Aggregate or an N_Extension_Aggregate. Typ is the type of the
124 -- aggregate. Target is an expression containing the location on which the
125 -- component by component assignments will take place. Returns the list of
126 -- assignments plus all other adjustments needed for tagged and controlled
129 procedure Convert_To_Assignments
(N
: Node_Id
; Typ
: Entity_Id
);
130 -- N is an N_Aggregate or an N_Extension_Aggregate. Typ is the type of the
131 -- aggregate (which can only be a record type, this procedure is only used
132 -- for record types). Transform the given aggregate into a sequence of
133 -- assignments performed component by component.
135 procedure Expand_Record_Aggregate
137 Orig_Tag
: Node_Id
:= Empty
;
138 Parent_Expr
: Node_Id
:= Empty
);
139 -- This is the top level procedure for record aggregate expansion.
140 -- Expansion for record aggregates needs expand aggregates for tagged
141 -- record types. Specifically Expand_Record_Aggregate adds the Tag
142 -- field in front of the Component_Association list that was created
143 -- during resolution by Resolve_Record_Aggregate.
145 -- N is the record aggregate node.
146 -- Orig_Tag is the value of the Tag that has to be provided for this
147 -- specific aggregate. It carries the tag corresponding to the type
148 -- of the outermost aggregate during the recursive expansion
149 -- Parent_Expr is the ancestor part of the original extension
152 function Has_Mutable_Components
(Typ
: Entity_Id
) return Boolean;
153 -- Return true if one of the components is of a discriminated type with
154 -- defaults. An aggregate for a type with mutable components must be
155 -- expanded into individual assignments.
157 procedure Initialize_Discriminants
(N
: Node_Id
; Typ
: Entity_Id
);
158 -- If the type of the aggregate is a type extension with renamed discrimi-
159 -- nants, we must initialize the hidden discriminants of the parent.
160 -- Otherwise, the target object must not be initialized. The discriminants
161 -- are initialized by calling the initialization procedure for the type.
162 -- This is incorrect if the initialization of other components has any
163 -- side effects. We restrict this call to the case where the parent type
164 -- has a variant part, because this is the only case where the hidden
165 -- discriminants are accessed, namely when calling discriminant checking
166 -- functions of the parent type, and when applying a stream attribute to
167 -- an object of the derived type.
169 -----------------------------------------------------
170 -- Local Subprograms for Array Aggregate Expansion --
171 -----------------------------------------------------
173 function Aggr_Size_OK
(N
: Node_Id
; Typ
: Entity_Id
) return Boolean;
174 -- Very large static aggregates present problems to the back-end, and are
175 -- transformed into assignments and loops. This function verifies that the
176 -- total number of components of an aggregate is acceptable for rewriting
177 -- into a purely positional static form. Aggr_Size_OK must be called before
180 -- This function also detects and warns about one-component aggregates that
181 -- appear in a non-static context. Even if the component value is static,
182 -- such an aggregate must be expanded into an assignment.
184 function Backend_Processing_Possible
(N
: Node_Id
) return Boolean;
185 -- This function checks if array aggregate N can be processed directly
186 -- by the backend. If this is the case, True is returned.
188 function Build_Array_Aggr_Code
193 Scalar_Comp
: Boolean;
194 Indexes
: List_Id
:= No_List
) return List_Id
;
195 -- This recursive routine returns a list of statements containing the
196 -- loops and assignments that are needed for the expansion of the array
199 -- N is the (sub-)aggregate node to be expanded into code. This node has
200 -- been fully analyzed, and its Etype is properly set.
202 -- Index is the index node corresponding to the array sub-aggregate N
204 -- Into is the target expression into which we are copying the aggregate.
205 -- Note that this node may not have been analyzed yet, and so the Etype
206 -- field may not be set.
208 -- Scalar_Comp is True if the component type of the aggregate is scalar
210 -- Indexes is the current list of expressions used to index the object we
213 procedure Convert_Array_Aggr_In_Allocator
217 -- If the aggregate appears within an allocator and can be expanded in
218 -- place, this routine generates the individual assignments to components
219 -- of the designated object. This is an optimization over the general
220 -- case, where a temporary is first created on the stack and then used to
221 -- construct the allocated object on the heap.
223 procedure Convert_To_Positional
225 Max_Others_Replicate
: Nat
:= 5;
226 Handle_Bit_Packed
: Boolean := False);
227 -- If possible, convert named notation to positional notation. This
228 -- conversion is possible only in some static cases. If the conversion is
229 -- possible, then N is rewritten with the analyzed converted aggregate.
230 -- The parameter Max_Others_Replicate controls the maximum number of
231 -- values corresponding to an others choice that will be converted to
232 -- positional notation (the default of 5 is the normal limit, and reflects
233 -- the fact that normally the loop is better than a lot of separate
234 -- assignments). Note that this limit gets overridden in any case if
235 -- either of the restrictions No_Elaboration_Code or No_Implicit_Loops is
236 -- set. The parameter Handle_Bit_Packed is usually set False (since we do
237 -- not expect the back end to handle bit packed arrays, so the normal case
238 -- of conversion is pointless), but in the special case of a call from
239 -- Packed_Array_Aggregate_Handled, we set this parameter to True, since
240 -- these are cases we handle in there.
242 -- It would seem useful to have a higher default for Max_Others_Replicate,
243 -- but aggregates in the compiler make this impossible: the compiler
244 -- bootstrap fails if Max_Others_Replicate is greater than 25. This
247 procedure Expand_Array_Aggregate
(N
: Node_Id
);
248 -- This is the top-level routine to perform array aggregate expansion.
249 -- N is the N_Aggregate node to be expanded.
251 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean;
252 -- For two-dimensional packed aggregates with constant bounds and constant
253 -- components, it is preferable to pack the inner aggregates because the
254 -- whole matrix can then be presented to the back-end as a one-dimensional
255 -- list of literals. This is much more efficient than expanding into single
256 -- component assignments. This function determines if the type Typ is for
257 -- an array that is suitable for this optimization: it returns True if Typ
258 -- is a two dimensional bit packed array with component size 1, 2, or 4.
260 function Late_Expansion
263 Target
: Node_Id
) return List_Id
;
264 -- This routine implements top-down expansion of nested aggregates. In
265 -- doing so, it avoids the generation of temporaries at each level. N is
266 -- a nested record or array aggregate with the Expansion_Delayed flag.
267 -- Typ is the expected type of the aggregate. Target is a (duplicatable)
268 -- expression that will hold the result of the aggregate expansion.
270 function Make_OK_Assignment_Statement
273 Expression
: Node_Id
) return Node_Id
;
274 -- This is like Make_Assignment_Statement, except that Assignment_OK
275 -- is set in the left operand. All assignments built by this unit use
276 -- this routine. This is needed to deal with assignments to initialized
277 -- constants that are done in place.
279 function Number_Of_Choices
(N
: Node_Id
) return Nat
;
280 -- Returns the number of discrete choices (not including the others choice
281 -- if present) contained in (sub-)aggregate N.
283 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean;
284 -- Given an array aggregate, this function handles the case of a packed
285 -- array aggregate with all constant values, where the aggregate can be
286 -- evaluated at compile time. If this is possible, then N is rewritten
287 -- to be its proper compile time value with all the components properly
288 -- assembled. The expression is analyzed and resolved and True is returned.
289 -- If this transformation is not possible, N is unchanged and False is
292 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean;
293 -- If the type of the aggregate is a two-dimensional bit_packed array
294 -- it may be transformed into an array of bytes with constant values,
295 -- and presented to the back-end as a static value. The function returns
296 -- false if this transformation cannot be performed. THis is similar to,
297 -- and reuses part of the machinery in Packed_Array_Aggregate_Handled.
303 function Aggr_Size_OK
(N
: Node_Id
; Typ
: Entity_Id
) return Boolean is
312 -- Determines the maximum size of an array aggregate produced by
313 -- converting named to positional notation (e.g. from others clauses).
314 -- This avoids running away with attempts to convert huge aggregates,
315 -- which hit memory limits in the backend.
317 function Component_Count
(T
: Entity_Id
) return Int
;
318 -- The limit is applied to the total number of components that the
319 -- aggregate will have, which is the number of static expressions
320 -- that will appear in the flattened array. This requires a recursive
321 -- computation of the number of scalar components of the structure.
323 ---------------------
324 -- Component_Count --
325 ---------------------
327 function Component_Count
(T
: Entity_Id
) return Int
is
332 if Is_Scalar_Type
(T
) then
335 elsif Is_Record_Type
(T
) then
336 Comp
:= First_Component
(T
);
337 while Present
(Comp
) loop
338 Res
:= Res
+ Component_Count
(Etype
(Comp
));
339 Next_Component
(Comp
);
344 elsif Is_Array_Type
(T
) then
346 Lo
: constant Node_Id
:=
347 Type_Low_Bound
(Etype
(First_Index
(T
)));
348 Hi
: constant Node_Id
:=
349 Type_High_Bound
(Etype
(First_Index
(T
)));
351 Siz
: constant Int
:= Component_Count
(Component_Type
(T
));
354 if not Compile_Time_Known_Value
(Lo
)
355 or else not Compile_Time_Known_Value
(Hi
)
360 Siz
* UI_To_Int
(Expr_Value
(Hi
) - Expr_Value
(Lo
) + 1);
365 -- Can only be a null for an access type
371 -- Start of processing for Aggr_Size_OK
374 -- The normal aggregate limit is 50000, but we increase this limit to
375 -- 2**24 (about 16 million) if Restrictions (No_Elaboration_Code) or
376 -- Restrictions (No_Implicit_Loops) is specified, since in either case
377 -- we are at risk of declaring the program illegal because of this
378 -- limit. We also increase the limit when Static_Elaboration_Desired,
379 -- given that this means that objects are intended to be placed in data
382 -- We also increase the limit if the aggregate is for a packed two-
383 -- dimensional array, because if components are static it is much more
384 -- efficient to construct a one-dimensional equivalent array with static
387 -- Conversely, we decrease the maximum size if none of the above
388 -- requirements apply, and if the aggregate has a single component
389 -- association, which will be more efficient if implemented with a loop.
391 -- Finally, we use a small limit in CodePeer mode where we favor loops
392 -- instead of thousands of single assignments (from large aggregates).
394 Max_Aggr_Size
:= 50000;
396 if CodePeer_Mode
then
397 Max_Aggr_Size
:= 100;
399 elsif Restriction_Active
(No_Elaboration_Code
)
400 or else Restriction_Active
(No_Implicit_Loops
)
401 or else Is_Two_Dim_Packed_Array
(Typ
)
402 or else (Ekind
(Current_Scope
) = E_Package
403 and then Static_Elaboration_Desired
(Current_Scope
))
405 Max_Aggr_Size
:= 2 ** 24;
407 elsif No
(Expressions
(N
))
408 and then No
(Next
(First
(Component_Associations
(N
))))
410 Max_Aggr_Size
:= 5000;
413 Siz
:= Component_Count
(Component_Type
(Typ
));
415 Indx
:= First_Index
(Typ
);
416 while Present
(Indx
) loop
417 Lo
:= Type_Low_Bound
(Etype
(Indx
));
418 Hi
:= Type_High_Bound
(Etype
(Indx
));
420 -- Bounds need to be known at compile time
422 if not Compile_Time_Known_Value
(Lo
)
423 or else not Compile_Time_Known_Value
(Hi
)
428 Lov
:= Expr_Value
(Lo
);
429 Hiv
:= Expr_Value
(Hi
);
431 -- A flat array is always safe
437 -- One-component aggregates are suspicious, and if the context type
438 -- is an object declaration with non-static bounds it will trip gcc;
439 -- such an aggregate must be expanded into a single assignment.
441 if Hiv
= Lov
and then Nkind
(Parent
(N
)) = N_Object_Declaration
then
443 Index_Type
: constant Entity_Id
:=
445 (First_Index
(Etype
(Defining_Identifier
(Parent
(N
)))));
449 if not Compile_Time_Known_Value
(Type_Low_Bound
(Index_Type
))
450 or else not Compile_Time_Known_Value
451 (Type_High_Bound
(Index_Type
))
453 if Present
(Component_Associations
(N
)) then
455 First
(Choices
(First
(Component_Associations
(N
))));
457 if Is_Entity_Name
(Indx
)
458 and then not Is_Type
(Entity
(Indx
))
461 ("single component aggregate in "
462 & "non-static context??", Indx
);
463 Error_Msg_N
("\maybe subtype name was meant??", Indx
);
473 Rng
: constant Uint
:= Hiv
- Lov
+ 1;
476 -- Check if size is too large
478 if not UI_Is_In_Int_Range
(Rng
) then
482 Siz
:= Siz
* UI_To_Int
(Rng
);
486 or else Siz
> Max_Aggr_Size
491 -- Bounds must be in integer range, for later array construction
493 if not UI_Is_In_Int_Range
(Lov
)
495 not UI_Is_In_Int_Range
(Hiv
)
506 ---------------------------------
507 -- Backend_Processing_Possible --
508 ---------------------------------
510 -- Backend processing by Gigi/gcc is possible only if all the following
511 -- conditions are met:
513 -- 1. N is fully positional
515 -- 2. N is not a bit-packed array aggregate;
517 -- 3. The size of N's array type must be known at compile time. Note
518 -- that this implies that the component size is also known
520 -- 4. The array type of N does not follow the Fortran layout convention
521 -- or if it does it must be 1 dimensional.
523 -- 5. The array component type may not be tagged (which could necessitate
524 -- reassignment of proper tags).
526 -- 6. The array component type must not have unaligned bit components
528 -- 7. None of the components of the aggregate may be bit unaligned
531 -- 8. There cannot be delayed components, since we do not know enough
532 -- at this stage to know if back end processing is possible.
534 -- 9. There cannot be any discriminated record components, since the
535 -- back end cannot handle this complex case.
537 -- 10. No controlled actions need to be generated for components
539 -- 11. For a VM back end, the array should have no aliased components
541 function Backend_Processing_Possible
(N
: Node_Id
) return Boolean is
542 Typ
: constant Entity_Id
:= Etype
(N
);
543 -- Typ is the correct constrained array subtype of the aggregate
545 function Component_Check
(N
: Node_Id
; Index
: Node_Id
) return Boolean;
546 -- This routine checks components of aggregate N, enforcing checks
547 -- 1, 7, 8, and 9. In the multi-dimensional case, these checks are
548 -- performed on subaggregates. The Index value is the current index
549 -- being checked in the multi-dimensional case.
551 ---------------------
552 -- Component_Check --
553 ---------------------
555 function Component_Check
(N
: Node_Id
; Index
: Node_Id
) return Boolean is
559 -- Checks 1: (no component associations)
561 if Present
(Component_Associations
(N
)) then
565 -- Checks on components
567 -- Recurse to check subaggregates, which may appear in qualified
568 -- expressions. If delayed, the front-end will have to expand.
569 -- If the component is a discriminated record, treat as non-static,
570 -- as the back-end cannot handle this properly.
572 Expr
:= First
(Expressions
(N
));
573 while Present
(Expr
) loop
575 -- Checks 8: (no delayed components)
577 if Is_Delayed_Aggregate
(Expr
) then
581 -- Checks 9: (no discriminated records)
583 if Present
(Etype
(Expr
))
584 and then Is_Record_Type
(Etype
(Expr
))
585 and then Has_Discriminants
(Etype
(Expr
))
590 -- Checks 7. Component must not be bit aligned component
592 if Possible_Bit_Aligned_Component
(Expr
) then
596 -- Recursion to following indexes for multiple dimension case
598 if Present
(Next_Index
(Index
))
599 and then not Component_Check
(Expr
, Next_Index
(Index
))
604 -- All checks for that component finished, on to next
612 -- Start of processing for Backend_Processing_Possible
615 -- Checks 2 (array not bit packed) and 10 (no controlled actions)
617 if Is_Bit_Packed_Array
(Typ
) or else Needs_Finalization
(Typ
) then
621 -- If component is limited, aggregate must be expanded because each
622 -- component assignment must be built in place.
624 if Is_Limited_View
(Component_Type
(Typ
)) then
628 -- Checks 4 (array must not be multi-dimensional Fortran case)
630 if Convention
(Typ
) = Convention_Fortran
631 and then Number_Dimensions
(Typ
) > 1
636 -- Checks 3 (size of array must be known at compile time)
638 if not Size_Known_At_Compile_Time
(Typ
) then
642 -- Checks on components
644 if not Component_Check
(N
, First_Index
(Typ
)) then
648 -- Checks 5 (if the component type is tagged, then we may need to do
649 -- tag adjustments. Perhaps this should be refined to check for any
650 -- component associations that actually need tag adjustment, similar
651 -- to the test in Component_Not_OK_For_Backend for record aggregates
652 -- with tagged components, but not clear whether it's worthwhile ???;
653 -- in the case of the JVM, object tags are handled implicitly)
655 if Is_Tagged_Type
(Component_Type
(Typ
))
656 and then Tagged_Type_Expansion
661 -- Checks 6 (component type must not have bit aligned components)
663 if Type_May_Have_Bit_Aligned_Components
(Component_Type
(Typ
)) then
667 -- Checks 11: Array aggregates with aliased components are currently
668 -- not well supported by the VM backend; disable temporarily this
669 -- backend processing until it is definitely supported.
671 if VM_Target
/= No_VM
672 and then Has_Aliased_Components
(Base_Type
(Typ
))
677 -- Backend processing is possible
679 Set_Size_Known_At_Compile_Time
(Etype
(N
), True);
681 end Backend_Processing_Possible
;
683 ---------------------------
684 -- Build_Array_Aggr_Code --
685 ---------------------------
687 -- The code that we generate from a one dimensional aggregate is
689 -- 1. If the sub-aggregate contains discrete choices we
691 -- (a) Sort the discrete choices
693 -- (b) Otherwise for each discrete choice that specifies a range we
694 -- emit a loop. If a range specifies a maximum of three values, or
695 -- we are dealing with an expression we emit a sequence of
696 -- assignments instead of a loop.
698 -- (c) Generate the remaining loops to cover the others choice if any
700 -- 2. If the aggregate contains positional elements we
702 -- (a) translate the positional elements in a series of assignments
704 -- (b) Generate a final loop to cover the others choice if any.
705 -- Note that this final loop has to be a while loop since the case
707 -- L : Integer := Integer'Last;
708 -- H : Integer := Integer'Last;
709 -- A : array (L .. H) := (1, others =>0);
711 -- cannot be handled by a for loop. Thus for the following
713 -- array (L .. H) := (.. positional elements.., others =>E);
715 -- we always generate something like:
717 -- J : Index_Type := Index_Of_Last_Positional_Element;
719 -- J := Index_Base'Succ (J)
723 function Build_Array_Aggr_Code
728 Scalar_Comp
: Boolean;
729 Indexes
: List_Id
:= No_List
) return List_Id
731 Loc
: constant Source_Ptr
:= Sloc
(N
);
732 Index_Base
: constant Entity_Id
:= Base_Type
(Etype
(Index
));
733 Index_Base_L
: constant Node_Id
:= Type_Low_Bound
(Index_Base
);
734 Index_Base_H
: constant Node_Id
:= Type_High_Bound
(Index_Base
);
736 function Add
(Val
: Int
; To
: Node_Id
) return Node_Id
;
737 -- Returns an expression where Val is added to expression To, unless
738 -- To+Val is provably out of To's base type range. To must be an
739 -- already analyzed expression.
741 function Empty_Range
(L
, H
: Node_Id
) return Boolean;
742 -- Returns True if the range defined by L .. H is certainly empty
744 function Equal
(L
, H
: Node_Id
) return Boolean;
745 -- Returns True if L = H for sure
747 function Index_Base_Name
return Node_Id
;
748 -- Returns a new reference to the index type name
750 function Gen_Assign
(Ind
: Node_Id
; Expr
: Node_Id
) return List_Id
;
751 -- Ind must be a side-effect free expression. If the input aggregate
752 -- N to Build_Loop contains no sub-aggregates, then this function
753 -- returns the assignment statement:
755 -- Into (Indexes, Ind) := Expr;
757 -- Otherwise we call Build_Code recursively
759 -- Ada 2005 (AI-287): In case of default initialized component, Expr
760 -- is empty and we generate a call to the corresponding IP subprogram.
762 function Gen_Loop
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
;
763 -- Nodes L and H must be side-effect free expressions.
764 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
765 -- This routine returns the for loop statement
767 -- for J in Index_Base'(L) .. Index_Base'(H) loop
768 -- Into (Indexes, J) := Expr;
771 -- Otherwise we call Build_Code recursively.
772 -- As an optimization if the loop covers 3 or less scalar elements we
773 -- generate a sequence of assignments.
775 function Gen_While
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
;
776 -- Nodes L and H must be side-effect free expressions.
777 -- If the input aggregate N to Build_Loop contains no sub-aggregates,
778 -- This routine returns the while loop statement
780 -- J : Index_Base := L;
782 -- J := Index_Base'Succ (J);
783 -- Into (Indexes, J) := Expr;
786 -- Otherwise we call Build_Code recursively
788 function Get_Assoc_Expr
(Assoc
: Node_Id
) return Node_Id
;
789 -- For an association with a box, use value given by aspect
790 -- Default_Component_Value of array type if specified, else use
791 -- value given by aspect Default_Value for component type itself
792 -- if specified, else return Empty.
794 function Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean;
795 function Local_Expr_Value
(E
: Node_Id
) return Uint
;
796 -- These two Local routines are used to replace the corresponding ones
797 -- in sem_eval because while processing the bounds of an aggregate with
798 -- discrete choices whose index type is an enumeration, we build static
799 -- expressions not recognized by Compile_Time_Known_Value as such since
800 -- they have not yet been analyzed and resolved. All the expressions in
801 -- question are things like Index_Base_Name'Val (Const) which we can
802 -- easily recognize as being constant.
808 function Add
(Val
: Int
; To
: Node_Id
) return Node_Id
is
813 U_Val
: constant Uint
:= UI_From_Int
(Val
);
816 -- Note: do not try to optimize the case of Val = 0, because
817 -- we need to build a new node with the proper Sloc value anyway.
819 -- First test if we can do constant folding
821 if Local_Compile_Time_Known_Value
(To
) then
822 U_To
:= Local_Expr_Value
(To
) + Val
;
824 -- Determine if our constant is outside the range of the index.
825 -- If so return an Empty node. This empty node will be caught
826 -- by Empty_Range below.
828 if Compile_Time_Known_Value
(Index_Base_L
)
829 and then U_To
< Expr_Value
(Index_Base_L
)
833 elsif Compile_Time_Known_Value
(Index_Base_H
)
834 and then U_To
> Expr_Value
(Index_Base_H
)
839 Expr_Pos
:= Make_Integer_Literal
(Loc
, U_To
);
840 Set_Is_Static_Expression
(Expr_Pos
);
842 if not Is_Enumeration_Type
(Index_Base
) then
845 -- If we are dealing with enumeration return
846 -- Index_Base'Val (Expr_Pos)
850 Make_Attribute_Reference
852 Prefix
=> Index_Base_Name
,
853 Attribute_Name
=> Name_Val
,
854 Expressions
=> New_List
(Expr_Pos
));
860 -- If we are here no constant folding possible
862 if not Is_Enumeration_Type
(Index_Base
) then
865 Left_Opnd
=> Duplicate_Subexpr
(To
),
866 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
868 -- If we are dealing with enumeration return
869 -- Index_Base'Val (Index_Base'Pos (To) + Val)
873 Make_Attribute_Reference
875 Prefix
=> Index_Base_Name
,
876 Attribute_Name
=> Name_Pos
,
877 Expressions
=> New_List
(Duplicate_Subexpr
(To
)));
882 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
885 Make_Attribute_Reference
887 Prefix
=> Index_Base_Name
,
888 Attribute_Name
=> Name_Val
,
889 Expressions
=> New_List
(Expr_Pos
));
899 function Empty_Range
(L
, H
: Node_Id
) return Boolean is
900 Is_Empty
: Boolean := False;
905 -- First check if L or H were already detected as overflowing the
906 -- index base range type by function Add above. If this is so Add
907 -- returns the empty node.
909 if No
(L
) or else No
(H
) then
916 -- L > H range is empty
922 -- B_L > H range must be empty
928 -- L > B_H range must be empty
932 High
:= Index_Base_H
;
935 if Local_Compile_Time_Known_Value
(Low
)
937 Local_Compile_Time_Known_Value
(High
)
940 UI_Gt
(Local_Expr_Value
(Low
), Local_Expr_Value
(High
));
953 function Equal
(L
, H
: Node_Id
) return Boolean is
958 elsif Local_Compile_Time_Known_Value
(L
)
960 Local_Compile_Time_Known_Value
(H
)
962 return UI_Eq
(Local_Expr_Value
(L
), Local_Expr_Value
(H
));
972 function Gen_Assign
(Ind
: Node_Id
; Expr
: Node_Id
) return List_Id
is
973 L
: constant List_Id
:= New_List
;
976 New_Indexes
: List_Id
;
977 Indexed_Comp
: Node_Id
;
979 Comp_Type
: Entity_Id
:= Empty
;
981 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
;
982 -- Collect insert_actions generated in the construction of a
983 -- loop, and prepend them to the sequence of assignments to
984 -- complete the eventual body of the loop.
986 ----------------------
987 -- Add_Loop_Actions --
988 ----------------------
990 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
is
994 -- Ada 2005 (AI-287): Do nothing else in case of default
995 -- initialized component.
1000 elsif Nkind
(Parent
(Expr
)) = N_Component_Association
1001 and then Present
(Loop_Actions
(Parent
(Expr
)))
1003 Append_List
(Lis
, Loop_Actions
(Parent
(Expr
)));
1004 Res
:= Loop_Actions
(Parent
(Expr
));
1005 Set_Loop_Actions
(Parent
(Expr
), No_List
);
1011 end Add_Loop_Actions
;
1013 -- Start of processing for Gen_Assign
1016 if No
(Indexes
) then
1017 New_Indexes
:= New_List
;
1019 New_Indexes
:= New_Copy_List_Tree
(Indexes
);
1022 Append_To
(New_Indexes
, Ind
);
1024 if Present
(Next_Index
(Index
)) then
1027 Build_Array_Aggr_Code
1030 Index
=> Next_Index
(Index
),
1032 Scalar_Comp
=> Scalar_Comp
,
1033 Indexes
=> New_Indexes
));
1036 -- If we get here then we are at a bottom-level (sub-)aggregate
1040 (Make_Indexed_Component
(Loc
,
1041 Prefix
=> New_Copy_Tree
(Into
),
1042 Expressions
=> New_Indexes
));
1044 Set_Assignment_OK
(Indexed_Comp
);
1046 -- Ada 2005 (AI-287): In case of default initialized component, Expr
1047 -- is not present (and therefore we also initialize Expr_Q to empty).
1051 elsif Nkind
(Expr
) = N_Qualified_Expression
then
1052 Expr_Q
:= Expression
(Expr
);
1057 if Present
(Etype
(N
)) and then Etype
(N
) /= Any_Composite
then
1058 Comp_Type
:= Component_Type
(Etype
(N
));
1059 pragma Assert
(Comp_Type
= Ctype
); -- AI-287
1061 elsif Present
(Next
(First
(New_Indexes
))) then
1063 -- Ada 2005 (AI-287): Do nothing in case of default initialized
1064 -- component because we have received the component type in
1065 -- the formal parameter Ctype.
1067 -- ??? Some assert pragmas have been added to check if this new
1068 -- formal can be used to replace this code in all cases.
1070 if Present
(Expr
) then
1072 -- This is a multidimensional array. Recover the component type
1073 -- from the outermost aggregate, because subaggregates do not
1074 -- have an assigned type.
1081 while Present
(P
) loop
1082 if Nkind
(P
) = N_Aggregate
1083 and then Present
(Etype
(P
))
1085 Comp_Type
:= Component_Type
(Etype
(P
));
1093 pragma Assert
(Comp_Type
= Ctype
); -- AI-287
1098 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
1099 -- default initialized components (otherwise Expr_Q is not present).
1102 and then Nkind_In
(Expr_Q
, N_Aggregate
, N_Extension_Aggregate
)
1104 -- At this stage the Expression may not have been analyzed yet
1105 -- because the array aggregate code has not been updated to use
1106 -- the Expansion_Delayed flag and avoid analysis altogether to
1107 -- solve the same problem (see Resolve_Aggr_Expr). So let us do
1108 -- the analysis of non-array aggregates now in order to get the
1109 -- value of Expansion_Delayed flag for the inner aggregate ???
1111 if Present
(Comp_Type
) and then not Is_Array_Type
(Comp_Type
) then
1112 Analyze_And_Resolve
(Expr_Q
, Comp_Type
);
1115 if Is_Delayed_Aggregate
(Expr_Q
) then
1117 -- This is either a subaggregate of a multidimensional array,
1118 -- or a component of an array type whose component type is
1119 -- also an array. In the latter case, the expression may have
1120 -- component associations that provide different bounds from
1121 -- those of the component type, and sliding must occur. Instead
1122 -- of decomposing the current aggregate assignment, force the
1123 -- re-analysis of the assignment, so that a temporary will be
1124 -- generated in the usual fashion, and sliding will take place.
1126 if Nkind
(Parent
(N
)) = N_Assignment_Statement
1127 and then Is_Array_Type
(Comp_Type
)
1128 and then Present
(Component_Associations
(Expr_Q
))
1129 and then Must_Slide
(Comp_Type
, Etype
(Expr_Q
))
1131 Set_Expansion_Delayed
(Expr_Q
, False);
1132 Set_Analyzed
(Expr_Q
, False);
1137 Late_Expansion
(Expr_Q
, Etype
(Expr_Q
), Indexed_Comp
));
1142 -- Ada 2005 (AI-287): In case of default initialized component, call
1143 -- the initialization subprogram associated with the component type.
1144 -- If the component type is an access type, add an explicit null
1145 -- assignment, because for the back-end there is an initialization
1146 -- present for the whole aggregate, and no default initialization
1149 -- In addition, if the component type is controlled, we must call
1150 -- its Initialize procedure explicitly, because there is no explicit
1151 -- object creation that will invoke it otherwise.
1154 if Present
(Base_Init_Proc
(Base_Type
(Ctype
)))
1155 or else Has_Task
(Base_Type
(Ctype
))
1158 Build_Initialization_Call
(Loc
,
1159 Id_Ref
=> Indexed_Comp
,
1161 With_Default_Init
=> True));
1163 -- If the component type has invariants, add an invariant
1164 -- check after the component is default-initialized. It will
1165 -- be analyzed and resolved before the code for initialization
1166 -- of other components.
1168 if Has_Invariants
(Ctype
) then
1169 Set_Etype
(Indexed_Comp
, Ctype
);
1170 Append_To
(L
, Make_Invariant_Call
(Indexed_Comp
));
1173 elsif Is_Access_Type
(Ctype
) then
1175 Make_Assignment_Statement
(Loc
,
1176 Name
=> Indexed_Comp
,
1177 Expression
=> Make_Null
(Loc
)));
1180 if Needs_Finalization
(Ctype
) then
1183 (Obj_Ref
=> New_Copy_Tree
(Indexed_Comp
),
1189 Make_OK_Assignment_Statement
(Loc
,
1190 Name
=> Indexed_Comp
,
1191 Expression
=> New_Copy_Tree
(Expr
));
1193 -- The target of the assignment may not have been initialized,
1194 -- so it is not possible to call Finalize as expected in normal
1195 -- controlled assignments. We must also avoid using the primitive
1196 -- _assign (which depends on a valid target, and may for example
1197 -- perform discriminant checks on it).
1199 -- Both Finalize and usage of _assign are disabled by setting
1200 -- No_Ctrl_Actions on the assignment. The rest of the controlled
1201 -- actions are done manually with the proper finalization list
1202 -- coming from the context.
1204 Set_No_Ctrl_Actions
(A
);
1206 -- If this is an aggregate for an array of arrays, each
1207 -- sub-aggregate will be expanded as well, and even with
1208 -- No_Ctrl_Actions the assignments of inner components will
1209 -- require attachment in their assignments to temporaries. These
1210 -- temporaries must be finalized for each subaggregate, to prevent
1211 -- multiple attachments of the same temporary location to same
1212 -- finalization chain (and consequently circular lists). To ensure
1213 -- that finalization takes place for each subaggregate we wrap the
1214 -- assignment in a block.
1216 if Present
(Comp_Type
)
1217 and then Needs_Finalization
(Comp_Type
)
1218 and then Is_Array_Type
(Comp_Type
)
1219 and then Present
(Expr
)
1222 Make_Block_Statement
(Loc
,
1223 Handled_Statement_Sequence
=>
1224 Make_Handled_Sequence_Of_Statements
(Loc
,
1225 Statements
=> New_List
(A
)));
1230 -- Adjust the tag if tagged (because of possible view
1231 -- conversions), unless compiling for a VM where tags
1234 if Present
(Comp_Type
)
1235 and then Is_Tagged_Type
(Comp_Type
)
1236 and then Tagged_Type_Expansion
1239 Full_Typ
: constant Entity_Id
:= Underlying_Type
(Comp_Type
);
1243 Make_OK_Assignment_Statement
(Loc
,
1245 Make_Selected_Component
(Loc
,
1246 Prefix
=> New_Copy_Tree
(Indexed_Comp
),
1249 (First_Tag_Component
(Full_Typ
), Loc
)),
1252 Unchecked_Convert_To
(RTE
(RE_Tag
),
1254 (Node
(First_Elmt
(Access_Disp_Table
(Full_Typ
))),
1261 -- Adjust and attach the component to the proper final list, which
1262 -- can be the controller of the outer record object or the final
1263 -- list associated with the scope.
1265 -- If the component is itself an array of controlled types, whose
1266 -- value is given by a sub-aggregate, then the attach calls have
1267 -- been generated when individual subcomponent are assigned, and
1268 -- must not be done again to prevent malformed finalization chains
1269 -- (see comments above, concerning the creation of a block to hold
1270 -- inner finalization actions).
1272 if Present
(Comp_Type
)
1273 and then Needs_Finalization
(Comp_Type
)
1274 and then not Is_Limited_Type
(Comp_Type
)
1276 (Is_Array_Type
(Comp_Type
)
1277 and then Is_Controlled
(Component_Type
(Comp_Type
))
1278 and then Nkind
(Expr
) = N_Aggregate
)
1282 (Obj_Ref
=> New_Copy_Tree
(Indexed_Comp
),
1287 return Add_Loop_Actions
(L
);
1294 function Gen_Loop
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1304 -- Index_Base'(L) .. Index_Base'(H)
1306 L_Iteration_Scheme
: Node_Id
;
1307 -- L_J in Index_Base'(L) .. Index_Base'(H)
1310 -- The statements to execute in the loop
1312 S
: constant List_Id
:= New_List
;
1313 -- List of statements
1316 -- Copy of expression tree, used for checking purposes
1319 -- If loop bounds define an empty range return the null statement
1321 if Empty_Range
(L
, H
) then
1322 Append_To
(S
, Make_Null_Statement
(Loc
));
1324 -- Ada 2005 (AI-287): Nothing else need to be done in case of
1325 -- default initialized component.
1331 -- The expression must be type-checked even though no component
1332 -- of the aggregate will have this value. This is done only for
1333 -- actual components of the array, not for subaggregates. Do
1334 -- the check on a copy, because the expression may be shared
1335 -- among several choices, some of which might be non-null.
1337 if Present
(Etype
(N
))
1338 and then Is_Array_Type
(Etype
(N
))
1339 and then No
(Next_Index
(Index
))
1341 Expander_Mode_Save_And_Set
(False);
1342 Tcopy
:= New_Copy_Tree
(Expr
);
1343 Set_Parent
(Tcopy
, N
);
1344 Analyze_And_Resolve
(Tcopy
, Component_Type
(Etype
(N
)));
1345 Expander_Mode_Restore
;
1351 -- If loop bounds are the same then generate an assignment
1353 elsif Equal
(L
, H
) then
1354 return Gen_Assign
(New_Copy_Tree
(L
), Expr
);
1356 -- If H - L <= 2 then generate a sequence of assignments when we are
1357 -- processing the bottom most aggregate and it contains scalar
1360 elsif No
(Next_Index
(Index
))
1361 and then Scalar_Comp
1362 and then Local_Compile_Time_Known_Value
(L
)
1363 and then Local_Compile_Time_Known_Value
(H
)
1364 and then Local_Expr_Value
(H
) - Local_Expr_Value
(L
) <= 2
1367 Append_List_To
(S
, Gen_Assign
(New_Copy_Tree
(L
), Expr
));
1368 Append_List_To
(S
, Gen_Assign
(Add
(1, To
=> L
), Expr
));
1370 if Local_Expr_Value
(H
) - Local_Expr_Value
(L
) = 2 then
1371 Append_List_To
(S
, Gen_Assign
(Add
(2, To
=> L
), Expr
));
1377 -- Otherwise construct the loop, starting with the loop index L_J
1379 L_J
:= Make_Temporary
(Loc
, 'J', L
);
1381 -- Construct "L .. H" in Index_Base. We use a qualified expression
1382 -- for the bound to convert to the index base, but we don't need
1383 -- to do that if we already have the base type at hand.
1385 if Etype
(L
) = Index_Base
then
1389 Make_Qualified_Expression
(Loc
,
1390 Subtype_Mark
=> Index_Base_Name
,
1394 if Etype
(H
) = Index_Base
then
1398 Make_Qualified_Expression
(Loc
,
1399 Subtype_Mark
=> Index_Base_Name
,
1408 -- Construct "for L_J in Index_Base range L .. H"
1410 L_Iteration_Scheme
:=
1411 Make_Iteration_Scheme
1413 Loop_Parameter_Specification
=>
1414 Make_Loop_Parameter_Specification
1416 Defining_Identifier
=> L_J
,
1417 Discrete_Subtype_Definition
=> L_Range
));
1419 -- Construct the statements to execute in the loop body
1421 L_Body
:= Gen_Assign
(New_Occurrence_Of
(L_J
, Loc
), Expr
);
1423 -- Construct the final loop
1426 Make_Implicit_Loop_Statement
1428 Identifier
=> Empty
,
1429 Iteration_Scheme
=> L_Iteration_Scheme
,
1430 Statements
=> L_Body
));
1432 -- A small optimization: if the aggregate is initialized with a box
1433 -- and the component type has no initialization procedure, remove the
1434 -- useless empty loop.
1436 if Nkind
(First
(S
)) = N_Loop_Statement
1437 and then Is_Empty_List
(Statements
(First
(S
)))
1439 return New_List
(Make_Null_Statement
(Loc
));
1449 -- The code built is
1451 -- W_J : Index_Base := L;
1452 -- while W_J < H loop
1453 -- W_J := Index_Base'Succ (W);
1457 function Gen_While
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1461 -- W_J : Base_Type := L;
1463 W_Iteration_Scheme
: Node_Id
;
1466 W_Index_Succ
: Node_Id
;
1467 -- Index_Base'Succ (J)
1469 W_Increment
: Node_Id
;
1470 -- W_J := Index_Base'Succ (W)
1472 W_Body
: constant List_Id
:= New_List
;
1473 -- The statements to execute in the loop
1475 S
: constant List_Id
:= New_List
;
1476 -- list of statement
1479 -- If loop bounds define an empty range or are equal return null
1481 if Empty_Range
(L
, H
) or else Equal
(L
, H
) then
1482 Append_To
(S
, Make_Null_Statement
(Loc
));
1486 -- Build the decl of W_J
1488 W_J
:= Make_Temporary
(Loc
, 'J', L
);
1490 Make_Object_Declaration
1492 Defining_Identifier
=> W_J
,
1493 Object_Definition
=> Index_Base_Name
,
1496 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1497 -- that in this particular case L is a fresh Expr generated by
1498 -- Add which we are the only ones to use.
1500 Append_To
(S
, W_Decl
);
1502 -- Construct " while W_J < H"
1504 W_Iteration_Scheme
:=
1505 Make_Iteration_Scheme
1507 Condition
=> Make_Op_Lt
1509 Left_Opnd
=> New_Occurrence_Of
(W_J
, Loc
),
1510 Right_Opnd
=> New_Copy_Tree
(H
)));
1512 -- Construct the statements to execute in the loop body
1515 Make_Attribute_Reference
1517 Prefix
=> Index_Base_Name
,
1518 Attribute_Name
=> Name_Succ
,
1519 Expressions
=> New_List
(New_Occurrence_Of
(W_J
, Loc
)));
1522 Make_OK_Assignment_Statement
1524 Name
=> New_Occurrence_Of
(W_J
, Loc
),
1525 Expression
=> W_Index_Succ
);
1527 Append_To
(W_Body
, W_Increment
);
1528 Append_List_To
(W_Body
,
1529 Gen_Assign
(New_Occurrence_Of
(W_J
, Loc
), Expr
));
1531 -- Construct the final loop
1534 Make_Implicit_Loop_Statement
1536 Identifier
=> Empty
,
1537 Iteration_Scheme
=> W_Iteration_Scheme
,
1538 Statements
=> W_Body
));
1543 --------------------
1544 -- Get_Assoc_Expr --
1545 --------------------
1547 function Get_Assoc_Expr
(Assoc
: Node_Id
) return Node_Id
is
1548 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
1551 if Box_Present
(Assoc
) then
1552 if Is_Scalar_Type
(Ctype
) then
1553 if Present
(Default_Aspect_Component_Value
(Typ
)) then
1554 return Default_Aspect_Component_Value
(Typ
);
1555 elsif Present
(Default_Aspect_Value
(Ctype
)) then
1556 return Default_Aspect_Value
(Ctype
);
1566 return Expression
(Assoc
);
1570 ---------------------
1571 -- Index_Base_Name --
1572 ---------------------
1574 function Index_Base_Name
return Node_Id
is
1576 return New_Occurrence_Of
(Index_Base
, Sloc
(N
));
1577 end Index_Base_Name
;
1579 ------------------------------------
1580 -- Local_Compile_Time_Known_Value --
1581 ------------------------------------
1583 function Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean is
1585 return Compile_Time_Known_Value
(E
)
1587 (Nkind
(E
) = N_Attribute_Reference
1588 and then Attribute_Name
(E
) = Name_Val
1589 and then Compile_Time_Known_Value
(First
(Expressions
(E
))));
1590 end Local_Compile_Time_Known_Value
;
1592 ----------------------
1593 -- Local_Expr_Value --
1594 ----------------------
1596 function Local_Expr_Value
(E
: Node_Id
) return Uint
is
1598 if Compile_Time_Known_Value
(E
) then
1599 return Expr_Value
(E
);
1601 return Expr_Value
(First
(Expressions
(E
)));
1603 end Local_Expr_Value
;
1605 -- Build_Array_Aggr_Code Variables
1612 Others_Assoc
: Node_Id
:= Empty
;
1614 Aggr_L
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(N
));
1615 Aggr_H
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(N
));
1616 -- The aggregate bounds of this specific sub-aggregate. Note that if
1617 -- the code generated by Build_Array_Aggr_Code is executed then these
1618 -- bounds are OK. Otherwise a Constraint_Error would have been raised.
1620 Aggr_Low
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_L
);
1621 Aggr_High
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_H
);
1622 -- After Duplicate_Subexpr these are side-effect free
1627 Nb_Choices
: Nat
:= 0;
1628 Table
: Case_Table_Type
(1 .. Number_Of_Choices
(N
));
1629 -- Used to sort all the different choice values
1632 -- Number of elements in the positional aggregate
1634 New_Code
: constant List_Id
:= New_List
;
1636 -- Start of processing for Build_Array_Aggr_Code
1639 -- First before we start, a special case. if we have a bit packed
1640 -- array represented as a modular type, then clear the value to
1641 -- zero first, to ensure that unused bits are properly cleared.
1646 and then Is_Bit_Packed_Array
(Typ
)
1647 and then Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
))
1649 Append_To
(New_Code
,
1650 Make_Assignment_Statement
(Loc
,
1651 Name
=> New_Copy_Tree
(Into
),
1653 Unchecked_Convert_To
(Typ
,
1654 Make_Integer_Literal
(Loc
, Uint_0
))));
1657 -- If the component type contains tasks, we need to build a Master
1658 -- entity in the current scope, because it will be needed if build-
1659 -- in-place functions are called in the expanded code.
1661 if Nkind
(Parent
(N
)) = N_Object_Declaration
and then Has_Task
(Typ
) then
1662 Build_Master_Entity
(Defining_Identifier
(Parent
(N
)));
1665 -- STEP 1: Process component associations
1667 -- For those associations that may generate a loop, initialize
1668 -- Loop_Actions to collect inserted actions that may be crated.
1670 -- Skip this if no component associations
1672 if No
(Expressions
(N
)) then
1674 -- STEP 1 (a): Sort the discrete choices
1676 Assoc
:= First
(Component_Associations
(N
));
1677 while Present
(Assoc
) loop
1678 Choice
:= First
(Choices
(Assoc
));
1679 while Present
(Choice
) loop
1680 if Nkind
(Choice
) = N_Others_Choice
then
1681 Set_Loop_Actions
(Assoc
, New_List
);
1682 Others_Assoc
:= Assoc
;
1686 Get_Index_Bounds
(Choice
, Low
, High
);
1689 Set_Loop_Actions
(Assoc
, New_List
);
1692 Nb_Choices
:= Nb_Choices
+ 1;
1694 Table
(Nb_Choices
) :=
1697 Choice_Node
=> Get_Assoc_Expr
(Assoc
));
1705 -- If there is more than one set of choices these must be static
1706 -- and we can therefore sort them. Remember that Nb_Choices does not
1707 -- account for an others choice.
1709 if Nb_Choices
> 1 then
1710 Sort_Case_Table
(Table
);
1713 -- STEP 1 (b): take care of the whole set of discrete choices
1715 for J
in 1 .. Nb_Choices
loop
1716 Low
:= Table
(J
).Choice_Lo
;
1717 High
:= Table
(J
).Choice_Hi
;
1718 Expr
:= Table
(J
).Choice_Node
;
1719 Append_List
(Gen_Loop
(Low
, High
, Expr
), To
=> New_Code
);
1722 -- STEP 1 (c): generate the remaining loops to cover others choice
1723 -- We don't need to generate loops over empty gaps, but if there is
1724 -- a single empty range we must analyze the expression for semantics
1726 if Present
(Others_Assoc
) then
1728 First
: Boolean := True;
1731 for J
in 0 .. Nb_Choices
loop
1735 Low
:= Add
(1, To
=> Table
(J
).Choice_Hi
);
1738 if J
= Nb_Choices
then
1741 High
:= Add
(-1, To
=> Table
(J
+ 1).Choice_Lo
);
1744 -- If this is an expansion within an init proc, make
1745 -- sure that discriminant references are replaced by
1746 -- the corresponding discriminal.
1748 if Inside_Init_Proc
then
1749 if Is_Entity_Name
(Low
)
1750 and then Ekind
(Entity
(Low
)) = E_Discriminant
1752 Set_Entity
(Low
, Discriminal
(Entity
(Low
)));
1755 if Is_Entity_Name
(High
)
1756 and then Ekind
(Entity
(High
)) = E_Discriminant
1758 Set_Entity
(High
, Discriminal
(Entity
(High
)));
1763 or else not Empty_Range
(Low
, High
)
1767 (Gen_Loop
(Low
, High
,
1768 Get_Assoc_Expr
(Others_Assoc
)), To
=> New_Code
);
1774 -- STEP 2: Process positional components
1777 -- STEP 2 (a): Generate the assignments for each positional element
1778 -- Note that here we have to use Aggr_L rather than Aggr_Low because
1779 -- Aggr_L is analyzed and Add wants an analyzed expression.
1781 Expr
:= First
(Expressions
(N
));
1783 while Present
(Expr
) loop
1784 Nb_Elements
:= Nb_Elements
+ 1;
1785 Append_List
(Gen_Assign
(Add
(Nb_Elements
, To
=> Aggr_L
), Expr
),
1790 -- STEP 2 (b): Generate final loop if an others choice is present
1791 -- Here Nb_Elements gives the offset of the last positional element.
1793 if Present
(Component_Associations
(N
)) then
1794 Assoc
:= Last
(Component_Associations
(N
));
1796 -- Ada 2005 (AI-287)
1798 Append_List
(Gen_While
(Add
(Nb_Elements
, To
=> Aggr_L
),
1800 Get_Assoc_Expr
(Assoc
)), -- AI-287
1806 end Build_Array_Aggr_Code
;
1808 ----------------------------
1809 -- Build_Record_Aggr_Code --
1810 ----------------------------
1812 function Build_Record_Aggr_Code
1815 Lhs
: Node_Id
) return List_Id
1817 Loc
: constant Source_Ptr
:= Sloc
(N
);
1818 L
: constant List_Id
:= New_List
;
1819 N_Typ
: constant Entity_Id
:= Etype
(N
);
1825 Comp_Type
: Entity_Id
;
1826 Selector
: Entity_Id
;
1827 Comp_Expr
: Node_Id
;
1830 -- If this is an internal aggregate, the External_Final_List is an
1831 -- expression for the controller record of the enclosing type.
1833 -- If the current aggregate has several controlled components, this
1834 -- expression will appear in several calls to attach to the finali-
1835 -- zation list, and it must not be shared.
1837 Ancestor_Is_Expression
: Boolean := False;
1838 Ancestor_Is_Subtype_Mark
: Boolean := False;
1840 Init_Typ
: Entity_Id
:= Empty
;
1842 Finalization_Done
: Boolean := False;
1843 -- True if Generate_Finalization_Actions has already been called; calls
1844 -- after the first do nothing.
1846 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
;
1847 -- Returns the value that the given discriminant of an ancestor type
1848 -- should receive (in the absence of a conflict with the value provided
1849 -- by an ancestor part of an extension aggregate).
1851 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
);
1852 -- Check that each of the discriminant values defined by the ancestor
1853 -- part of an extension aggregate match the corresponding values
1854 -- provided by either an association of the aggregate or by the
1855 -- constraint imposed by a parent type (RM95-4.3.2(8)).
1857 function Compatible_Int_Bounds
1858 (Agg_Bounds
: Node_Id
;
1859 Typ_Bounds
: Node_Id
) return Boolean;
1860 -- Return true if Agg_Bounds are equal or within Typ_Bounds. It is
1861 -- assumed that both bounds are integer ranges.
1863 procedure Generate_Finalization_Actions
;
1864 -- Deal with the various controlled type data structure initializations
1865 -- (but only if it hasn't been done already).
1867 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
;
1868 -- Returns the first discriminant association in the constraint
1869 -- associated with T, if any, otherwise returns Empty.
1871 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
);
1872 -- If Typ is derived, and constrains discriminants of the parent type,
1873 -- these discriminants are not components of the aggregate, and must be
1874 -- initialized. The assignments are appended to List. The same is done
1875 -- if Typ derives fron an already constrained subtype of a discriminated
1878 function Get_Explicit_Discriminant_Value
(D
: Entity_Id
) return Node_Id
;
1879 -- If the ancestor part is an unconstrained type and further ancestors
1880 -- do not provide discriminants for it, check aggregate components for
1881 -- values of the discriminants.
1883 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean;
1884 -- Check whether Bounds is a range node and its lower and higher bounds
1885 -- are integers literals.
1887 ---------------------------------
1888 -- Ancestor_Discriminant_Value --
1889 ---------------------------------
1891 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
is
1893 Assoc_Elmt
: Elmt_Id
;
1894 Aggr_Comp
: Entity_Id
;
1895 Corresp_Disc
: Entity_Id
;
1896 Current_Typ
: Entity_Id
:= Base_Type
(Typ
);
1897 Parent_Typ
: Entity_Id
;
1898 Parent_Disc
: Entity_Id
;
1899 Save_Assoc
: Node_Id
:= Empty
;
1902 -- First check any discriminant associations to see if any of them
1903 -- provide a value for the discriminant.
1905 if Present
(Discriminant_Specifications
(Parent
(Current_Typ
))) then
1906 Assoc
:= First
(Component_Associations
(N
));
1907 while Present
(Assoc
) loop
1908 Aggr_Comp
:= Entity
(First
(Choices
(Assoc
)));
1910 if Ekind
(Aggr_Comp
) = E_Discriminant
then
1911 Save_Assoc
:= Expression
(Assoc
);
1913 Corresp_Disc
:= Corresponding_Discriminant
(Aggr_Comp
);
1914 while Present
(Corresp_Disc
) loop
1916 -- If found a corresponding discriminant then return the
1917 -- value given in the aggregate. (Note: this is not
1918 -- correct in the presence of side effects. ???)
1920 if Disc
= Corresp_Disc
then
1921 return Duplicate_Subexpr
(Expression
(Assoc
));
1924 Corresp_Disc
:= Corresponding_Discriminant
(Corresp_Disc
);
1932 -- No match found in aggregate, so chain up parent types to find
1933 -- a constraint that defines the value of the discriminant.
1935 Parent_Typ
:= Etype
(Current_Typ
);
1936 while Current_Typ
/= Parent_Typ
loop
1937 if Has_Discriminants
(Parent_Typ
)
1938 and then not Has_Unknown_Discriminants
(Parent_Typ
)
1940 Parent_Disc
:= First_Discriminant
(Parent_Typ
);
1942 -- We either get the association from the subtype indication
1943 -- of the type definition itself, or from the discriminant
1944 -- constraint associated with the type entity (which is
1945 -- preferable, but it's not always present ???)
1947 if Is_Empty_Elmt_List
(
1948 Discriminant_Constraint
(Current_Typ
))
1950 Assoc
:= Get_Constraint_Association
(Current_Typ
);
1951 Assoc_Elmt
:= No_Elmt
;
1954 First_Elmt
(Discriminant_Constraint
(Current_Typ
));
1955 Assoc
:= Node
(Assoc_Elmt
);
1958 -- Traverse the discriminants of the parent type looking
1959 -- for one that corresponds.
1961 while Present
(Parent_Disc
) and then Present
(Assoc
) loop
1962 Corresp_Disc
:= Parent_Disc
;
1963 while Present
(Corresp_Disc
)
1964 and then Disc
/= Corresp_Disc
1966 Corresp_Disc
:= Corresponding_Discriminant
(Corresp_Disc
);
1969 if Disc
= Corresp_Disc
then
1970 if Nkind
(Assoc
) = N_Discriminant_Association
then
1971 Assoc
:= Expression
(Assoc
);
1974 -- If the located association directly denotes
1975 -- a discriminant, then use the value of a saved
1976 -- association of the aggregate. This is an approach
1977 -- used to handle certain cases involving multiple
1978 -- discriminants mapped to a single discriminant of
1979 -- a descendant. It's not clear how to locate the
1980 -- appropriate discriminant value for such cases. ???
1982 if Is_Entity_Name
(Assoc
)
1983 and then Ekind
(Entity
(Assoc
)) = E_Discriminant
1985 Assoc
:= Save_Assoc
;
1988 return Duplicate_Subexpr
(Assoc
);
1991 Next_Discriminant
(Parent_Disc
);
1993 if No
(Assoc_Elmt
) then
1997 Next_Elmt
(Assoc_Elmt
);
1999 if Present
(Assoc_Elmt
) then
2000 Assoc
:= Node
(Assoc_Elmt
);
2008 Current_Typ
:= Parent_Typ
;
2009 Parent_Typ
:= Etype
(Current_Typ
);
2012 -- In some cases there's no ancestor value to locate (such as
2013 -- when an ancestor part given by an expression defines the
2014 -- discriminant value).
2017 end Ancestor_Discriminant_Value
;
2019 ----------------------------------
2020 -- Check_Ancestor_Discriminants --
2021 ----------------------------------
2023 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
) is
2025 Disc_Value
: Node_Id
;
2029 Discr
:= First_Discriminant
(Base_Type
(Anc_Typ
));
2030 while Present
(Discr
) loop
2031 Disc_Value
:= Ancestor_Discriminant_Value
(Discr
);
2033 if Present
(Disc_Value
) then
2034 Cond
:= Make_Op_Ne
(Loc
,
2036 Make_Selected_Component
(Loc
,
2037 Prefix
=> New_Copy_Tree
(Target
),
2038 Selector_Name
=> New_Occurrence_Of
(Discr
, Loc
)),
2039 Right_Opnd
=> Disc_Value
);
2042 Make_Raise_Constraint_Error
(Loc
,
2044 Reason
=> CE_Discriminant_Check_Failed
));
2047 Next_Discriminant
(Discr
);
2049 end Check_Ancestor_Discriminants
;
2051 ---------------------------
2052 -- Compatible_Int_Bounds --
2053 ---------------------------
2055 function Compatible_Int_Bounds
2056 (Agg_Bounds
: Node_Id
;
2057 Typ_Bounds
: Node_Id
) return Boolean
2059 Agg_Lo
: constant Uint
:= Intval
(Low_Bound
(Agg_Bounds
));
2060 Agg_Hi
: constant Uint
:= Intval
(High_Bound
(Agg_Bounds
));
2061 Typ_Lo
: constant Uint
:= Intval
(Low_Bound
(Typ_Bounds
));
2062 Typ_Hi
: constant Uint
:= Intval
(High_Bound
(Typ_Bounds
));
2064 return Typ_Lo
<= Agg_Lo
and then Agg_Hi
<= Typ_Hi
;
2065 end Compatible_Int_Bounds
;
2067 --------------------------------
2068 -- Get_Constraint_Association --
2069 --------------------------------
2071 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
is
2078 -- If type is private, get constraint from full view. This was
2079 -- previously done in an instance context, but is needed whenever
2080 -- the ancestor part has a discriminant, possibly inherited through
2081 -- multiple derivations.
2083 if Is_Private_Type
(Typ
) and then Present
(Full_View
(Typ
)) then
2084 Typ
:= Full_View
(Typ
);
2087 Indic
:= Subtype_Indication
(Type_Definition
(Parent
(Typ
)));
2089 -- Verify that the subtype indication carries a constraint
2091 if Nkind
(Indic
) = N_Subtype_Indication
2092 and then Present
(Constraint
(Indic
))
2094 return First
(Constraints
(Constraint
(Indic
)));
2098 end Get_Constraint_Association
;
2100 -------------------------------------
2101 -- Get_Explicit_Discriminant_Value --
2102 -------------------------------------
2104 function Get_Explicit_Discriminant_Value
2105 (D
: Entity_Id
) return Node_Id
2112 -- The aggregate has been normalized and all associations have a
2115 Assoc
:= First
(Component_Associations
(N
));
2116 while Present
(Assoc
) loop
2117 Choice
:= First
(Choices
(Assoc
));
2119 if Chars
(Choice
) = Chars
(D
) then
2120 Val
:= Expression
(Assoc
);
2129 end Get_Explicit_Discriminant_Value
;
2131 -------------------------------
2132 -- Init_Hidden_Discriminants --
2133 -------------------------------
2135 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
) is
2137 Parent_Type
: Entity_Id
;
2139 Discr_Val
: Elmt_Id
;
2140 In_Aggr_Type
: Boolean;
2143 -- The constraints on the hidden discriminants, if present, are kept
2144 -- in the Stored_Constraint list of the type itself, or in that of
2145 -- the base type. If not in the constraints of the aggregate itself,
2146 -- we examine ancestors to find discriminants that are not renamed
2147 -- by other discriminants but constrained explicitly.
2149 In_Aggr_Type
:= True;
2151 Btype
:= Base_Type
(Typ
);
2152 while Is_Derived_Type
(Btype
)
2154 (Present
(Stored_Constraint
(Btype
))
2156 (In_Aggr_Type
and then Present
(Stored_Constraint
(Typ
))))
2158 Parent_Type
:= Etype
(Btype
);
2160 if not Has_Discriminants
(Parent_Type
) then
2164 Disc
:= First_Discriminant
(Parent_Type
);
2166 -- We know that one of the stored-constraint lists is present
2168 if Present
(Stored_Constraint
(Btype
)) then
2169 Discr_Val
:= First_Elmt
(Stored_Constraint
(Btype
));
2171 -- For private extension, stored constraint may be on full view
2173 elsif Is_Private_Type
(Btype
)
2174 and then Present
(Full_View
(Btype
))
2175 and then Present
(Stored_Constraint
(Full_View
(Btype
)))
2177 Discr_Val
:= First_Elmt
(Stored_Constraint
(Full_View
(Btype
)));
2180 Discr_Val
:= First_Elmt
(Stored_Constraint
(Typ
));
2183 while Present
(Discr_Val
) and then Present
(Disc
) loop
2185 -- Only those discriminants of the parent that are not
2186 -- renamed by discriminants of the derived type need to
2187 -- be added explicitly.
2189 if not Is_Entity_Name
(Node
(Discr_Val
))
2190 or else Ekind
(Entity
(Node
(Discr_Val
))) /= E_Discriminant
2193 Make_Selected_Component
(Loc
,
2194 Prefix
=> New_Copy_Tree
(Target
),
2195 Selector_Name
=> New_Occurrence_Of
(Disc
, Loc
));
2198 Make_OK_Assignment_Statement
(Loc
,
2200 Expression
=> New_Copy_Tree
(Node
(Discr_Val
)));
2202 Set_No_Ctrl_Actions
(Instr
);
2203 Append_To
(List
, Instr
);
2206 Next_Discriminant
(Disc
);
2207 Next_Elmt
(Discr_Val
);
2210 In_Aggr_Type
:= False;
2211 Btype
:= Base_Type
(Parent_Type
);
2213 end Init_Hidden_Discriminants
;
2215 -------------------------
2216 -- Is_Int_Range_Bounds --
2217 -------------------------
2219 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean is
2221 return Nkind
(Bounds
) = N_Range
2222 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
2223 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
;
2224 end Is_Int_Range_Bounds
;
2226 -----------------------------------
2227 -- Generate_Finalization_Actions --
2228 -----------------------------------
2230 procedure Generate_Finalization_Actions
is
2232 -- Do the work only the first time this is called
2234 if Finalization_Done
then
2238 Finalization_Done
:= True;
2240 -- Determine the external finalization list. It is either the
2241 -- finalization list of the outer-scope or the one coming from an
2242 -- outer aggregate. When the target is not a temporary, the proper
2243 -- scope is the scope of the target rather than the potentially
2244 -- transient current scope.
2246 if Is_Controlled
(Typ
) and then Ancestor_Is_Subtype_Mark
then
2247 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2248 Set_Assignment_OK
(Ref
);
2251 Make_Procedure_Call_Statement
(Loc
,
2254 (Find_Prim_Op
(Init_Typ
, Name_Initialize
), Loc
),
2255 Parameter_Associations
=> New_List
(New_Copy_Tree
(Ref
))));
2257 end Generate_Finalization_Actions
;
2259 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
;
2260 -- If default expression of a component mentions a discriminant of the
2261 -- type, it must be rewritten as the discriminant of the target object.
2263 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
;
2264 -- If the aggregate contains a self-reference, traverse each expression
2265 -- to replace a possible self-reference with a reference to the proper
2266 -- component of the target of the assignment.
2268 --------------------------
2269 -- Rewrite_Discriminant --
2270 --------------------------
2272 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
is
2274 if Is_Entity_Name
(Expr
)
2275 and then Present
(Entity
(Expr
))
2276 and then Ekind
(Entity
(Expr
)) = E_In_Parameter
2277 and then Present
(Discriminal_Link
(Entity
(Expr
)))
2278 and then Scope
(Discriminal_Link
(Entity
(Expr
))) =
2279 Base_Type
(Etype
(N
))
2282 Make_Selected_Component
(Loc
,
2283 Prefix
=> New_Copy_Tree
(Lhs
),
2284 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Expr
))));
2288 end Rewrite_Discriminant
;
2294 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
is
2296 -- Note regarding the Root_Type test below: Aggregate components for
2297 -- self-referential types include attribute references to the current
2298 -- instance, of the form: Typ'access, etc.. These references are
2299 -- rewritten as references to the target of the aggregate: the
2300 -- left-hand side of an assignment, the entity in a declaration,
2301 -- or a temporary. Without this test, we would improperly extended
2302 -- this rewriting to attribute references whose prefix was not the
2303 -- type of the aggregate.
2305 if Nkind
(Expr
) = N_Attribute_Reference
2306 and then Is_Entity_Name
(Prefix
(Expr
))
2307 and then Is_Type
(Entity
(Prefix
(Expr
)))
2308 and then Root_Type
(Etype
(N
)) = Root_Type
(Entity
(Prefix
(Expr
)))
2310 if Is_Entity_Name
(Lhs
) then
2311 Rewrite
(Prefix
(Expr
),
2312 New_Occurrence_Of
(Entity
(Lhs
), Loc
));
2314 elsif Nkind
(Lhs
) = N_Selected_Component
then
2316 Make_Attribute_Reference
(Loc
,
2317 Attribute_Name
=> Name_Unrestricted_Access
,
2318 Prefix
=> New_Copy_Tree
(Lhs
)));
2319 Set_Analyzed
(Parent
(Expr
), False);
2323 Make_Attribute_Reference
(Loc
,
2324 Attribute_Name
=> Name_Unrestricted_Access
,
2325 Prefix
=> New_Copy_Tree
(Lhs
)));
2326 Set_Analyzed
(Parent
(Expr
), False);
2333 procedure Replace_Self_Reference
is
2334 new Traverse_Proc
(Replace_Type
);
2336 procedure Replace_Discriminants
is
2337 new Traverse_Proc
(Rewrite_Discriminant
);
2339 -- Start of processing for Build_Record_Aggr_Code
2342 if Has_Self_Reference
(N
) then
2343 Replace_Self_Reference
(N
);
2346 -- If the target of the aggregate is class-wide, we must convert it
2347 -- to the actual type of the aggregate, so that the proper components
2348 -- are visible. We know already that the types are compatible.
2350 if Present
(Etype
(Lhs
))
2351 and then Is_Class_Wide_Type
(Etype
(Lhs
))
2353 Target
:= Unchecked_Convert_To
(Typ
, Lhs
);
2358 -- Deal with the ancestor part of extension aggregates or with the
2359 -- discriminants of the root type.
2361 if Nkind
(N
) = N_Extension_Aggregate
then
2363 Ancestor
: constant Node_Id
:= Ancestor_Part
(N
);
2367 -- If the ancestor part is a subtype mark "T", we generate
2369 -- init-proc (T (tmp)); if T is constrained and
2370 -- init-proc (S (tmp)); where S applies an appropriate
2371 -- constraint if T is unconstrained
2373 if Is_Entity_Name
(Ancestor
)
2374 and then Is_Type
(Entity
(Ancestor
))
2376 Ancestor_Is_Subtype_Mark
:= True;
2378 if Is_Constrained
(Entity
(Ancestor
)) then
2379 Init_Typ
:= Entity
(Ancestor
);
2381 -- For an ancestor part given by an unconstrained type mark,
2382 -- create a subtype constrained by appropriate corresponding
2383 -- discriminant values coming from either associations of the
2384 -- aggregate or a constraint on a parent type. The subtype will
2385 -- be used to generate the correct default value for the
2388 elsif Has_Discriminants
(Entity
(Ancestor
)) then
2390 Anc_Typ
: constant Entity_Id
:= Entity
(Ancestor
);
2391 Anc_Constr
: constant List_Id
:= New_List
;
2392 Discrim
: Entity_Id
;
2393 Disc_Value
: Node_Id
;
2394 New_Indic
: Node_Id
;
2395 Subt_Decl
: Node_Id
;
2398 Discrim
:= First_Discriminant
(Anc_Typ
);
2399 while Present
(Discrim
) loop
2400 Disc_Value
:= Ancestor_Discriminant_Value
(Discrim
);
2402 -- If no usable discriminant in ancestors, check
2403 -- whether aggregate has an explicit value for it.
2405 if No
(Disc_Value
) then
2407 Get_Explicit_Discriminant_Value
(Discrim
);
2410 Append_To
(Anc_Constr
, Disc_Value
);
2411 Next_Discriminant
(Discrim
);
2415 Make_Subtype_Indication
(Loc
,
2416 Subtype_Mark
=> New_Occurrence_Of
(Anc_Typ
, Loc
),
2418 Make_Index_Or_Discriminant_Constraint
(Loc
,
2419 Constraints
=> Anc_Constr
));
2421 Init_Typ
:= Create_Itype
(Ekind
(Anc_Typ
), N
);
2424 Make_Subtype_Declaration
(Loc
,
2425 Defining_Identifier
=> Init_Typ
,
2426 Subtype_Indication
=> New_Indic
);
2428 -- Itypes must be analyzed with checks off Declaration
2429 -- must have a parent for proper handling of subsidiary
2432 Set_Parent
(Subt_Decl
, N
);
2433 Analyze
(Subt_Decl
, Suppress
=> All_Checks
);
2437 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2438 Set_Assignment_OK
(Ref
);
2440 if not Is_Interface
(Init_Typ
) then
2442 Build_Initialization_Call
(Loc
,
2445 In_Init_Proc
=> Within_Init_Proc
,
2446 With_Default_Init
=> Has_Default_Init_Comps
(N
)
2448 Has_Task
(Base_Type
(Init_Typ
))));
2450 if Is_Constrained
(Entity
(Ancestor
))
2451 and then Has_Discriminants
(Entity
(Ancestor
))
2453 Check_Ancestor_Discriminants
(Entity
(Ancestor
));
2457 -- Handle calls to C++ constructors
2459 elsif Is_CPP_Constructor_Call
(Ancestor
) then
2460 Init_Typ
:= Etype
(Ancestor
);
2461 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2462 Set_Assignment_OK
(Ref
);
2465 Build_Initialization_Call
(Loc
,
2468 In_Init_Proc
=> Within_Init_Proc
,
2469 With_Default_Init
=> Has_Default_Init_Comps
(N
),
2470 Constructor_Ref
=> Ancestor
));
2472 -- Ada 2005 (AI-287): If the ancestor part is an aggregate of
2473 -- limited type, a recursive call expands the ancestor. Note that
2474 -- in the limited case, the ancestor part must be either a
2475 -- function call (possibly qualified, or wrapped in an unchecked
2476 -- conversion) or aggregate (definitely qualified).
2478 -- The ancestor part can also be a function call (that may be
2479 -- transformed into an explicit dereference) or a qualification
2482 elsif Is_Limited_Type
(Etype
(Ancestor
))
2483 and then Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
2484 N_Extension_Aggregate
)
2486 Ancestor_Is_Expression
:= True;
2488 -- Set up finalization data for enclosing record, because
2489 -- controlled subcomponents of the ancestor part will be
2492 Generate_Finalization_Actions
;
2495 Build_Record_Aggr_Code
2496 (N
=> Unqualify
(Ancestor
),
2497 Typ
=> Etype
(Unqualify
(Ancestor
)),
2500 -- If the ancestor part is an expression "E", we generate
2504 -- In Ada 2005, this includes the case of a (possibly qualified)
2505 -- limited function call. The assignment will turn into a
2506 -- build-in-place function call (for further details, see
2507 -- Make_Build_In_Place_Call_In_Assignment).
2510 Ancestor_Is_Expression
:= True;
2511 Init_Typ
:= Etype
(Ancestor
);
2513 -- If the ancestor part is an aggregate, force its full
2514 -- expansion, which was delayed.
2516 if Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
2517 N_Extension_Aggregate
)
2519 Set_Analyzed
(Ancestor
, False);
2520 Set_Analyzed
(Expression
(Ancestor
), False);
2523 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2524 Set_Assignment_OK
(Ref
);
2526 -- Make the assignment without usual controlled actions, since
2527 -- we only want to Adjust afterwards, but not to Finalize
2528 -- beforehand. Add manual Adjust when necessary.
2530 Assign
:= New_List
(
2531 Make_OK_Assignment_Statement
(Loc
,
2533 Expression
=> Ancestor
));
2534 Set_No_Ctrl_Actions
(First
(Assign
));
2536 -- Assign the tag now to make sure that the dispatching call in
2537 -- the subsequent deep_adjust works properly (unless VM_Target,
2538 -- where tags are implicit).
2540 if Tagged_Type_Expansion
then
2542 Make_OK_Assignment_Statement
(Loc
,
2544 Make_Selected_Component
(Loc
,
2545 Prefix
=> New_Copy_Tree
(Target
),
2548 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
2551 Unchecked_Convert_To
(RTE
(RE_Tag
),
2554 (Access_Disp_Table
(Base_Type
(Typ
)))),
2557 Set_Assignment_OK
(Name
(Instr
));
2558 Append_To
(Assign
, Instr
);
2560 -- Ada 2005 (AI-251): If tagged type has progenitors we must
2561 -- also initialize tags of the secondary dispatch tables.
2563 if Has_Interfaces
(Base_Type
(Typ
)) then
2565 (Typ
=> Base_Type
(Typ
),
2567 Stmts_List
=> Assign
);
2571 -- Call Adjust manually
2573 if Needs_Finalization
(Etype
(Ancestor
))
2574 and then not Is_Limited_Type
(Etype
(Ancestor
))
2578 (Obj_Ref
=> New_Copy_Tree
(Ref
),
2579 Typ
=> Etype
(Ancestor
)));
2583 Make_Unsuppress_Block
(Loc
, Name_Discriminant_Check
, Assign
));
2585 if Has_Discriminants
(Init_Typ
) then
2586 Check_Ancestor_Discriminants
(Init_Typ
);
2591 -- Generate assignments of hidden discriminants. If the base type is
2592 -- an unchecked union, the discriminants are unknown to the back-end
2593 -- and absent from a value of the type, so assignments for them are
2596 if Has_Discriminants
(Typ
)
2597 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
2599 Init_Hidden_Discriminants
(Typ
, L
);
2602 -- Normal case (not an extension aggregate)
2605 -- Generate the discriminant expressions, component by component.
2606 -- If the base type is an unchecked union, the discriminants are
2607 -- unknown to the back-end and absent from a value of the type, so
2608 -- assignments for them are not emitted.
2610 if Has_Discriminants
(Typ
)
2611 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
2613 Init_Hidden_Discriminants
(Typ
, L
);
2615 -- Generate discriminant init values for the visible discriminants
2618 Discriminant
: Entity_Id
;
2619 Discriminant_Value
: Node_Id
;
2622 Discriminant
:= First_Stored_Discriminant
(Typ
);
2623 while Present
(Discriminant
) loop
2625 Make_Selected_Component
(Loc
,
2626 Prefix
=> New_Copy_Tree
(Target
),
2627 Selector_Name
=> New_Occurrence_Of
(Discriminant
, Loc
));
2629 Discriminant_Value
:=
2630 Get_Discriminant_Value
2633 Discriminant_Constraint
(N_Typ
));
2636 Make_OK_Assignment_Statement
(Loc
,
2638 Expression
=> New_Copy_Tree
(Discriminant_Value
));
2640 Set_No_Ctrl_Actions
(Instr
);
2641 Append_To
(L
, Instr
);
2643 Next_Stored_Discriminant
(Discriminant
);
2649 -- For CPP types we generate an implicit call to the C++ default
2650 -- constructor to ensure the proper initialization of the _Tag
2653 if Is_CPP_Class
(Root_Type
(Typ
)) and then CPP_Num_Prims
(Typ
) > 0 then
2654 Invoke_Constructor
: declare
2655 CPP_Parent
: constant Entity_Id
:= Enclosing_CPP_Parent
(Typ
);
2657 procedure Invoke_IC_Proc
(T
: Entity_Id
);
2658 -- Recursive routine used to climb to parents. Required because
2659 -- parents must be initialized before descendants to ensure
2660 -- propagation of inherited C++ slots.
2662 --------------------
2663 -- Invoke_IC_Proc --
2664 --------------------
2666 procedure Invoke_IC_Proc
(T
: Entity_Id
) is
2668 -- Avoid generating extra calls. Initialization required
2669 -- only for types defined from the level of derivation of
2670 -- type of the constructor and the type of the aggregate.
2672 if T
= CPP_Parent
then
2676 Invoke_IC_Proc
(Etype
(T
));
2678 -- Generate call to the IC routine
2680 if Present
(CPP_Init_Proc
(T
)) then
2682 Make_Procedure_Call_Statement
(Loc
,
2683 Name
=> New_Occurrence_Of
(CPP_Init_Proc
(T
), Loc
)));
2687 -- Start of processing for Invoke_Constructor
2690 -- Implicit invocation of the C++ constructor
2692 if Nkind
(N
) = N_Aggregate
then
2694 Make_Procedure_Call_Statement
(Loc
,
2696 New_Occurrence_Of
(Base_Init_Proc
(CPP_Parent
), Loc
),
2697 Parameter_Associations
=> New_List
(
2698 Unchecked_Convert_To
(CPP_Parent
,
2699 New_Copy_Tree
(Lhs
)))));
2702 Invoke_IC_Proc
(Typ
);
2703 end Invoke_Constructor
;
2706 -- Generate the assignments, component by component
2708 -- tmp.comp1 := Expr1_From_Aggr;
2709 -- tmp.comp2 := Expr2_From_Aggr;
2712 Comp
:= First
(Component_Associations
(N
));
2713 while Present
(Comp
) loop
2714 Selector
:= Entity
(First
(Choices
(Comp
)));
2718 if Is_CPP_Constructor_Call
(Expression
(Comp
)) then
2720 Build_Initialization_Call
(Loc
,
2722 Make_Selected_Component
(Loc
,
2723 Prefix
=> New_Copy_Tree
(Target
),
2724 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
)),
2725 Typ
=> Etype
(Selector
),
2727 With_Default_Init
=> True,
2728 Constructor_Ref
=> Expression
(Comp
)));
2730 -- Ada 2005 (AI-287): For each default-initialized component generate
2731 -- a call to the corresponding IP subprogram if available.
2733 elsif Box_Present
(Comp
)
2734 and then Has_Non_Null_Base_Init_Proc
(Etype
(Selector
))
2736 if Ekind
(Selector
) /= E_Discriminant
then
2737 Generate_Finalization_Actions
;
2740 -- Ada 2005 (AI-287): If the component type has tasks then
2741 -- generate the activation chain and master entities (except
2742 -- in case of an allocator because in that case these entities
2743 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
2746 Ctype
: constant Entity_Id
:= Etype
(Selector
);
2747 Inside_Allocator
: Boolean := False;
2748 P
: Node_Id
:= Parent
(N
);
2751 if Is_Task_Type
(Ctype
) or else Has_Task
(Ctype
) then
2752 while Present
(P
) loop
2753 if Nkind
(P
) = N_Allocator
then
2754 Inside_Allocator
:= True;
2761 if not Inside_Init_Proc
and not Inside_Allocator
then
2762 Build_Activation_Chain_Entity
(N
);
2768 Build_Initialization_Call
(Loc
,
2769 Id_Ref
=> Make_Selected_Component
(Loc
,
2770 Prefix
=> New_Copy_Tree
(Target
),
2772 New_Occurrence_Of
(Selector
, Loc
)),
2773 Typ
=> Etype
(Selector
),
2775 With_Default_Init
=> True));
2777 -- Prepare for component assignment
2779 elsif Ekind
(Selector
) /= E_Discriminant
2780 or else Nkind
(N
) = N_Extension_Aggregate
2782 -- All the discriminants have now been assigned
2784 -- This is now a good moment to initialize and attach all the
2785 -- controllers. Their position may depend on the discriminants.
2787 if Ekind
(Selector
) /= E_Discriminant
then
2788 Generate_Finalization_Actions
;
2791 Comp_Type
:= Underlying_Type
(Etype
(Selector
));
2793 Make_Selected_Component
(Loc
,
2794 Prefix
=> New_Copy_Tree
(Target
),
2795 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
));
2797 if Nkind
(Expression
(Comp
)) = N_Qualified_Expression
then
2798 Expr_Q
:= Expression
(Expression
(Comp
));
2800 Expr_Q
:= Expression
(Comp
);
2803 -- Now either create the assignment or generate the code for the
2804 -- inner aggregate top-down.
2806 if Is_Delayed_Aggregate
(Expr_Q
) then
2808 -- We have the following case of aggregate nesting inside
2809 -- an object declaration:
2811 -- type Arr_Typ is array (Integer range <>) of ...;
2813 -- type Rec_Typ (...) is record
2814 -- Obj_Arr_Typ : Arr_Typ (A .. B);
2817 -- Obj_Rec_Typ : Rec_Typ := (...,
2818 -- Obj_Arr_Typ => (X => (...), Y => (...)));
2820 -- The length of the ranges of the aggregate and Obj_Add_Typ
2821 -- are equal (B - A = Y - X), but they do not coincide (X /=
2822 -- A and B /= Y). This case requires array sliding which is
2823 -- performed in the following manner:
2825 -- subtype Arr_Sub is Arr_Typ (X .. Y);
2827 -- Temp (X) := (...);
2829 -- Temp (Y) := (...);
2830 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
2832 if Ekind
(Comp_Type
) = E_Array_Subtype
2833 and then Is_Int_Range_Bounds
(Aggregate_Bounds
(Expr_Q
))
2834 and then Is_Int_Range_Bounds
(First_Index
(Comp_Type
))
2836 Compatible_Int_Bounds
2837 (Agg_Bounds
=> Aggregate_Bounds
(Expr_Q
),
2838 Typ_Bounds
=> First_Index
(Comp_Type
))
2840 -- Create the array subtype with bounds equal to those of
2841 -- the corresponding aggregate.
2844 SubE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
2846 SubD
: constant Node_Id
:=
2847 Make_Subtype_Declaration
(Loc
,
2848 Defining_Identifier
=> SubE
,
2849 Subtype_Indication
=>
2850 Make_Subtype_Indication
(Loc
,
2852 New_Occurrence_Of
(Etype
(Comp_Type
), Loc
),
2854 Make_Index_Or_Discriminant_Constraint
2856 Constraints
=> New_List
(
2858 (Aggregate_Bounds
(Expr_Q
))))));
2860 -- Create a temporary array of the above subtype which
2861 -- will be used to capture the aggregate assignments.
2863 TmpE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A', N
);
2865 TmpD
: constant Node_Id
:=
2866 Make_Object_Declaration
(Loc
,
2867 Defining_Identifier
=> TmpE
,
2868 Object_Definition
=> New_Occurrence_Of
(SubE
, Loc
));
2871 Set_No_Initialization
(TmpD
);
2872 Append_To
(L
, SubD
);
2873 Append_To
(L
, TmpD
);
2875 -- Expand aggregate into assignments to the temp array
2878 Late_Expansion
(Expr_Q
, Comp_Type
,
2879 New_Occurrence_Of
(TmpE
, Loc
)));
2884 Make_Assignment_Statement
(Loc
,
2885 Name
=> New_Copy_Tree
(Comp_Expr
),
2886 Expression
=> New_Occurrence_Of
(TmpE
, Loc
)));
2889 -- Normal case (sliding not required)
2893 Late_Expansion
(Expr_Q
, Comp_Type
, Comp_Expr
));
2896 -- Expr_Q is not delayed aggregate
2899 if Has_Discriminants
(Typ
) then
2900 Replace_Discriminants
(Expr_Q
);
2902 -- If the component is an array type that depends on
2903 -- discriminants, and the expression is a single Others
2904 -- clause, create an explicit subtype for it because the
2905 -- backend has troubles recovering the actual bounds.
2907 if Nkind
(Expr_Q
) = N_Aggregate
2908 and then Is_Array_Type
(Comp_Type
)
2909 and then Present
(Component_Associations
(Expr_Q
))
2912 Assoc
: constant Node_Id
:=
2913 First
(Component_Associations
(Expr_Q
));
2917 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
2920 Build_Actual_Subtype_Of_Component
2921 (Comp_Type
, Comp_Expr
);
2923 -- If the component type does not in fact depend on
2924 -- discriminants, the subtype declaration is empty.
2926 if Present
(Decl
) then
2927 Append_To
(L
, Decl
);
2928 Set_Etype
(Comp_Expr
, Defining_Entity
(Decl
));
2936 Make_OK_Assignment_Statement
(Loc
,
2938 Expression
=> Expr_Q
);
2940 Set_No_Ctrl_Actions
(Instr
);
2941 Append_To
(L
, Instr
);
2943 -- Adjust the tag if tagged (because of possible view
2944 -- conversions), unless compiling for a VM where tags are
2947 -- tmp.comp._tag := comp_typ'tag;
2949 if Is_Tagged_Type
(Comp_Type
)
2950 and then Tagged_Type_Expansion
2953 Make_OK_Assignment_Statement
(Loc
,
2955 Make_Selected_Component
(Loc
,
2956 Prefix
=> New_Copy_Tree
(Comp_Expr
),
2959 (First_Tag_Component
(Comp_Type
), Loc
)),
2962 Unchecked_Convert_To
(RTE
(RE_Tag
),
2964 (Node
(First_Elmt
(Access_Disp_Table
(Comp_Type
))),
2967 Append_To
(L
, Instr
);
2971 -- Adjust (tmp.comp);
2973 if Needs_Finalization
(Comp_Type
)
2974 and then not Is_Limited_Type
(Comp_Type
)
2978 (Obj_Ref
=> New_Copy_Tree
(Comp_Expr
),
2983 -- comment would be good here ???
2985 elsif Ekind
(Selector
) = E_Discriminant
2986 and then Nkind
(N
) /= N_Extension_Aggregate
2987 and then Nkind
(Parent
(N
)) = N_Component_Association
2988 and then Is_Constrained
(Typ
)
2990 -- We must check that the discriminant value imposed by the
2991 -- context is the same as the value given in the subaggregate,
2992 -- because after the expansion into assignments there is no
2993 -- record on which to perform a regular discriminant check.
3000 D_Val
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3001 Disc
:= First_Discriminant
(Typ
);
3002 while Chars
(Disc
) /= Chars
(Selector
) loop
3003 Next_Discriminant
(Disc
);
3007 pragma Assert
(Present
(D_Val
));
3009 -- This check cannot performed for components that are
3010 -- constrained by a current instance, because this is not a
3011 -- value that can be compared with the actual constraint.
3013 if Nkind
(Node
(D_Val
)) /= N_Attribute_Reference
3014 or else not Is_Entity_Name
(Prefix
(Node
(D_Val
)))
3015 or else not Is_Type
(Entity
(Prefix
(Node
(D_Val
))))
3018 Make_Raise_Constraint_Error
(Loc
,
3021 Left_Opnd
=> New_Copy_Tree
(Node
(D_Val
)),
3022 Right_Opnd
=> Expression
(Comp
)),
3023 Reason
=> CE_Discriminant_Check_Failed
));
3026 -- Find self-reference in previous discriminant assignment,
3027 -- and replace with proper expression.
3034 while Present
(Ass
) loop
3035 if Nkind
(Ass
) = N_Assignment_Statement
3036 and then Nkind
(Name
(Ass
)) = N_Selected_Component
3037 and then Chars
(Selector_Name
(Name
(Ass
))) =
3041 (Ass
, New_Copy_Tree
(Expression
(Comp
)));
3054 -- If the type is tagged, the tag needs to be initialized (unless we
3055 -- are in VM-mode where tags are implicit). It is done late in the
3056 -- initialization process because in some cases, we call the init
3057 -- proc of an ancestor which will not leave out the right tag.
3059 if Ancestor_Is_Expression
then
3062 -- For CPP types we generated a call to the C++ default constructor
3063 -- before the components have been initialized to ensure the proper
3064 -- initialization of the _Tag component (see above).
3066 elsif Is_CPP_Class
(Typ
) then
3069 elsif Is_Tagged_Type
(Typ
) and then Tagged_Type_Expansion
then
3071 Make_OK_Assignment_Statement
(Loc
,
3073 Make_Selected_Component
(Loc
,
3074 Prefix
=> New_Copy_Tree
(Target
),
3077 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
3080 Unchecked_Convert_To
(RTE
(RE_Tag
),
3082 (Node
(First_Elmt
(Access_Disp_Table
(Base_Type
(Typ
)))),
3085 Append_To
(L
, Instr
);
3087 -- Ada 2005 (AI-251): If the tagged type has been derived from an
3088 -- abstract interfaces we must also initialize the tags of the
3089 -- secondary dispatch tables.
3091 if Has_Interfaces
(Base_Type
(Typ
)) then
3093 (Typ
=> Base_Type
(Typ
),
3099 -- If the controllers have not been initialized yet (by lack of non-
3100 -- discriminant components), let's do it now.
3102 Generate_Finalization_Actions
;
3105 end Build_Record_Aggr_Code
;
3107 ---------------------------------------
3108 -- Collect_Initialization_Statements --
3109 ---------------------------------------
3111 procedure Collect_Initialization_Statements
3114 Node_After
: Node_Id
)
3116 Loc
: constant Source_Ptr
:= Sloc
(N
);
3117 Init_Actions
: constant List_Id
:= New_List
;
3118 Init_Node
: Node_Id
;
3119 Comp_Stmt
: Node_Id
;
3122 -- Nothing to do if Obj is already frozen, as in this case we known we
3123 -- won't need to move the initialization statements about later on.
3125 if Is_Frozen
(Obj
) then
3130 while Next
(Init_Node
) /= Node_After
loop
3131 Append_To
(Init_Actions
, Remove_Next
(Init_Node
));
3134 if not Is_Empty_List
(Init_Actions
) then
3135 Comp_Stmt
:= Make_Compound_Statement
(Loc
, Actions
=> Init_Actions
);
3136 Insert_Action_After
(Init_Node
, Comp_Stmt
);
3137 Set_Initialization_Statements
(Obj
, Comp_Stmt
);
3139 end Collect_Initialization_Statements
;
3141 -------------------------------
3142 -- Convert_Aggr_In_Allocator --
3143 -------------------------------
3145 procedure Convert_Aggr_In_Allocator
3150 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3151 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3152 Temp
: constant Entity_Id
:= Defining_Identifier
(Decl
);
3154 Occ
: constant Node_Id
:=
3155 Unchecked_Convert_To
(Typ
,
3156 Make_Explicit_Dereference
(Loc
, New_Occurrence_Of
(Temp
, Loc
)));
3159 if Is_Array_Type
(Typ
) then
3160 Convert_Array_Aggr_In_Allocator
(Decl
, Aggr
, Occ
);
3162 elsif Has_Default_Init_Comps
(Aggr
) then
3164 L
: constant List_Id
:= New_List
;
3165 Init_Stmts
: List_Id
;
3168 Init_Stmts
:= Late_Expansion
(Aggr
, Typ
, Occ
);
3170 if Has_Task
(Typ
) then
3171 Build_Task_Allocate_Block_With_Init_Stmts
(L
, Aggr
, Init_Stmts
);
3172 Insert_Actions
(Alloc
, L
);
3174 Insert_Actions
(Alloc
, Init_Stmts
);
3179 Insert_Actions
(Alloc
, Late_Expansion
(Aggr
, Typ
, Occ
));
3181 end Convert_Aggr_In_Allocator
;
3183 --------------------------------
3184 -- Convert_Aggr_In_Assignment --
3185 --------------------------------
3187 procedure Convert_Aggr_In_Assignment
(N
: Node_Id
) is
3188 Aggr
: Node_Id
:= Expression
(N
);
3189 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3190 Occ
: constant Node_Id
:= New_Copy_Tree
(Name
(N
));
3193 if Nkind
(Aggr
) = N_Qualified_Expression
then
3194 Aggr
:= Expression
(Aggr
);
3197 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3198 end Convert_Aggr_In_Assignment
;
3200 ---------------------------------
3201 -- Convert_Aggr_In_Object_Decl --
3202 ---------------------------------
3204 procedure Convert_Aggr_In_Object_Decl
(N
: Node_Id
) is
3205 Obj
: constant Entity_Id
:= Defining_Identifier
(N
);
3206 Aggr
: Node_Id
:= Expression
(N
);
3207 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3208 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3209 Occ
: constant Node_Id
:= New_Occurrence_Of
(Obj
, Loc
);
3211 function Discriminants_Ok
return Boolean;
3212 -- If the object type is constrained, the discriminants in the
3213 -- aggregate must be checked against the discriminants of the subtype.
3214 -- This cannot be done using Apply_Discriminant_Checks because after
3215 -- expansion there is no aggregate left to check.
3217 ----------------------
3218 -- Discriminants_Ok --
3219 ----------------------
3221 function Discriminants_Ok
return Boolean is
3222 Cond
: Node_Id
:= Empty
;
3231 D
:= First_Discriminant
(Typ
);
3232 Disc1
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3233 Disc2
:= First_Elmt
(Discriminant_Constraint
(Etype
(Obj
)));
3234 while Present
(Disc1
) and then Present
(Disc2
) loop
3235 Val1
:= Node
(Disc1
);
3236 Val2
:= Node
(Disc2
);
3238 if not Is_OK_Static_Expression
(Val1
)
3239 or else not Is_OK_Static_Expression
(Val2
)
3241 Check
:= Make_Op_Ne
(Loc
,
3242 Left_Opnd
=> Duplicate_Subexpr
(Val1
),
3243 Right_Opnd
=> Duplicate_Subexpr
(Val2
));
3249 Cond
:= Make_Or_Else
(Loc
,
3251 Right_Opnd
=> Check
);
3254 elsif Expr_Value
(Val1
) /= Expr_Value
(Val2
) then
3255 Apply_Compile_Time_Constraint_Error
(Aggr
,
3256 Msg
=> "incorrect value for discriminant&??",
3257 Reason
=> CE_Discriminant_Check_Failed
,
3262 Next_Discriminant
(D
);
3267 -- If any discriminant constraint is non-static, emit a check
3269 if Present
(Cond
) then
3271 Make_Raise_Constraint_Error
(Loc
,
3273 Reason
=> CE_Discriminant_Check_Failed
));
3277 end Discriminants_Ok
;
3279 -- Start of processing for Convert_Aggr_In_Object_Decl
3282 Set_Assignment_OK
(Occ
);
3284 if Nkind
(Aggr
) = N_Qualified_Expression
then
3285 Aggr
:= Expression
(Aggr
);
3288 if Has_Discriminants
(Typ
)
3289 and then Typ
/= Etype
(Obj
)
3290 and then Is_Constrained
(Etype
(Obj
))
3291 and then not Discriminants_Ok
3296 -- If the context is an extended return statement, it has its own
3297 -- finalization machinery (i.e. works like a transient scope) and
3298 -- we do not want to create an additional one, because objects on
3299 -- the finalization list of the return must be moved to the caller's
3300 -- finalization list to complete the return.
3302 -- However, if the aggregate is limited, it is built in place, and the
3303 -- controlled components are not assigned to intermediate temporaries
3304 -- so there is no need for a transient scope in this case either.
3306 if Requires_Transient_Scope
(Typ
)
3307 and then Ekind
(Current_Scope
) /= E_Return_Statement
3308 and then not Is_Limited_Type
(Typ
)
3310 Establish_Transient_Scope
3313 Is_Controlled
(Typ
) or else Has_Controlled_Component
(Typ
));
3317 Node_After
: constant Node_Id
:= Next
(N
);
3319 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3320 Collect_Initialization_Statements
(Obj
, N
, Node_After
);
3322 Set_No_Initialization
(N
);
3323 Initialize_Discriminants
(N
, Typ
);
3324 end Convert_Aggr_In_Object_Decl
;
3326 -------------------------------------
3327 -- Convert_Array_Aggr_In_Allocator --
3328 -------------------------------------
3330 procedure Convert_Array_Aggr_In_Allocator
3335 Aggr_Code
: List_Id
;
3336 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3337 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
3340 -- The target is an explicit dereference of the allocated object.
3341 -- Generate component assignments to it, as for an aggregate that
3342 -- appears on the right-hand side of an assignment statement.
3345 Build_Array_Aggr_Code
(Aggr
,
3347 Index
=> First_Index
(Typ
),
3349 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
3351 Insert_Actions_After
(Decl
, Aggr_Code
);
3352 end Convert_Array_Aggr_In_Allocator
;
3354 ----------------------------
3355 -- Convert_To_Assignments --
3356 ----------------------------
3358 procedure Convert_To_Assignments
(N
: Node_Id
; Typ
: Entity_Id
) is
3359 Loc
: constant Source_Ptr
:= Sloc
(N
);
3363 Aggr_Code
: List_Id
;
3365 Target_Expr
: Node_Id
;
3366 Parent_Kind
: Node_Kind
;
3367 Unc_Decl
: Boolean := False;
3368 Parent_Node
: Node_Id
;
3371 pragma Assert
(not Is_Static_Dispatch_Table_Aggregate
(N
));
3372 pragma Assert
(Is_Record_Type
(Typ
));
3374 Parent_Node
:= Parent
(N
);
3375 Parent_Kind
:= Nkind
(Parent_Node
);
3377 if Parent_Kind
= N_Qualified_Expression
then
3379 -- Check if we are in a unconstrained declaration because in this
3380 -- case the current delayed expansion mechanism doesn't work when
3381 -- the declared object size depend on the initializing expr.
3384 Parent_Node
:= Parent
(Parent_Node
);
3385 Parent_Kind
:= Nkind
(Parent_Node
);
3387 if Parent_Kind
= N_Object_Declaration
then
3389 not Is_Entity_Name
(Object_Definition
(Parent_Node
))
3390 or else Has_Discriminants
3391 (Entity
(Object_Definition
(Parent_Node
)))
3392 or else Is_Class_Wide_Type
3393 (Entity
(Object_Definition
(Parent_Node
)));
3398 -- Just set the Delay flag in the cases where the transformation will be
3399 -- done top down from above.
3403 -- Internal aggregate (transformed when expanding the parent)
3405 or else Parent_Kind
= N_Aggregate
3406 or else Parent_Kind
= N_Extension_Aggregate
3407 or else Parent_Kind
= N_Component_Association
3409 -- Allocator (see Convert_Aggr_In_Allocator)
3411 or else Parent_Kind
= N_Allocator
3413 -- Object declaration (see Convert_Aggr_In_Object_Decl)
3415 or else (Parent_Kind
= N_Object_Declaration
and then not Unc_Decl
)
3417 -- Safe assignment (see Convert_Aggr_Assignments). So far only the
3418 -- assignments in init procs are taken into account.
3420 or else (Parent_Kind
= N_Assignment_Statement
3421 and then Inside_Init_Proc
)
3423 -- (Ada 2005) An inherently limited type in a return statement, which
3424 -- will be handled in a build-in-place fashion, and may be rewritten
3425 -- as an extended return and have its own finalization machinery.
3426 -- In the case of a simple return, the aggregate needs to be delayed
3427 -- until the scope for the return statement has been created, so
3428 -- that any finalization chain will be associated with that scope.
3429 -- For extended returns, we delay expansion to avoid the creation
3430 -- of an unwanted transient scope that could result in premature
3431 -- finalization of the return object (which is built in place
3432 -- within the caller's scope).
3435 (Is_Limited_View
(Typ
)
3437 (Nkind
(Parent
(Parent_Node
)) = N_Extended_Return_Statement
3438 or else Nkind
(Parent_Node
) = N_Simple_Return_Statement
))
3440 Set_Expansion_Delayed
(N
);
3444 -- Otherwise, if a transient scope is required, create it now. If we
3445 -- are within an initialization procedure do not create such, because
3446 -- the target of the assignment must not be declared within a local
3447 -- block, and because cleanup will take place on return from the
3448 -- initialization procedure.
3449 -- Should the condition be more restrictive ???
3451 if Requires_Transient_Scope
(Typ
) and then not Inside_Init_Proc
then
3452 Establish_Transient_Scope
(N
, Sec_Stack
=> Needs_Finalization
(Typ
));
3455 -- If the aggregate is non-limited, create a temporary. If it is limited
3456 -- and context is an assignment, this is a subaggregate for an enclosing
3457 -- aggregate being expanded. It must be built in place, so use target of
3458 -- the current assignment.
3460 if Is_Limited_Type
(Typ
)
3461 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
3463 Target_Expr
:= New_Copy_Tree
(Name
(Parent
(N
)));
3464 Insert_Actions
(Parent
(N
),
3465 Build_Record_Aggr_Code
(N
, Typ
, Target_Expr
));
3466 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
3469 Temp
:= Make_Temporary
(Loc
, 'A', N
);
3471 -- If the type inherits unknown discriminants, use the view with
3472 -- known discriminants if available.
3474 if Has_Unknown_Discriminants
(Typ
)
3475 and then Present
(Underlying_Record_View
(Typ
))
3477 T
:= Underlying_Record_View
(Typ
);
3483 Make_Object_Declaration
(Loc
,
3484 Defining_Identifier
=> Temp
,
3485 Object_Definition
=> New_Occurrence_Of
(T
, Loc
));
3487 Set_No_Initialization
(Instr
);
3488 Insert_Action
(N
, Instr
);
3489 Initialize_Discriminants
(Instr
, T
);
3491 Target_Expr
:= New_Occurrence_Of
(Temp
, Loc
);
3492 Aggr_Code
:= Build_Record_Aggr_Code
(N
, T
, Target_Expr
);
3494 -- Save the last assignment statement associated with the aggregate
3495 -- when building a controlled object. This reference is utilized by
3496 -- the finalization machinery when marking an object as successfully
3499 if Needs_Finalization
(T
) then
3500 Set_Last_Aggregate_Assignment
(Temp
, Last
(Aggr_Code
));
3503 Insert_Actions
(N
, Aggr_Code
);
3504 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
3505 Analyze_And_Resolve
(N
, T
);
3507 end Convert_To_Assignments
;
3509 ---------------------------
3510 -- Convert_To_Positional --
3511 ---------------------------
3513 procedure Convert_To_Positional
3515 Max_Others_Replicate
: Nat
:= 5;
3516 Handle_Bit_Packed
: Boolean := False)
3518 Typ
: constant Entity_Id
:= Etype
(N
);
3520 Static_Components
: Boolean := True;
3522 procedure Check_Static_Components
;
3523 -- Check whether all components of the aggregate are compile-time known
3524 -- values, and can be passed as is to the back-end without further
3530 Ixb
: Node_Id
) return Boolean;
3531 -- Convert the aggregate into a purely positional form if possible. On
3532 -- entry the bounds of all dimensions are known to be static, and the
3533 -- total number of components is safe enough to expand.
3535 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean;
3536 -- Return True iff the array N is flat (which is not trivial in the case
3537 -- of multidimensional aggregates).
3539 -----------------------------
3540 -- Check_Static_Components --
3541 -----------------------------
3543 -- Could use some comments in this body ???
3545 procedure Check_Static_Components
is
3549 Static_Components
:= True;
3551 if Nkind
(N
) = N_String_Literal
then
3554 elsif Present
(Expressions
(N
)) then
3555 Expr
:= First
(Expressions
(N
));
3556 while Present
(Expr
) loop
3557 if Nkind
(Expr
) /= N_Aggregate
3558 or else not Compile_Time_Known_Aggregate
(Expr
)
3559 or else Expansion_Delayed
(Expr
)
3561 Static_Components
:= False;
3569 if Nkind
(N
) = N_Aggregate
3570 and then Present
(Component_Associations
(N
))
3572 Expr
:= First
(Component_Associations
(N
));
3573 while Present
(Expr
) loop
3574 if Nkind_In
(Expression
(Expr
), N_Integer_Literal
,
3579 elsif Is_Entity_Name
(Expression
(Expr
))
3580 and then Present
(Entity
(Expression
(Expr
)))
3581 and then Ekind
(Entity
(Expression
(Expr
))) =
3582 E_Enumeration_Literal
3586 elsif Nkind
(Expression
(Expr
)) /= N_Aggregate
3587 or else not Compile_Time_Known_Aggregate
(Expression
(Expr
))
3588 or else Expansion_Delayed
(Expression
(Expr
))
3590 Static_Components
:= False;
3597 end Check_Static_Components
;
3606 Ixb
: Node_Id
) return Boolean
3608 Loc
: constant Source_Ptr
:= Sloc
(N
);
3609 Blo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ixb
));
3610 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ix
));
3611 Hi
: constant Node_Id
:= Type_High_Bound
(Etype
(Ix
));
3615 Others_Present
: Boolean := False;
3618 if Nkind
(Original_Node
(N
)) = N_String_Literal
then
3622 if not Compile_Time_Known_Value
(Lo
)
3623 or else not Compile_Time_Known_Value
(Hi
)
3628 Lov
:= Expr_Value
(Lo
);
3629 Hiv
:= Expr_Value
(Hi
);
3631 -- Check if there is an others choice
3633 if Present
(Component_Associations
(N
)) then
3639 Assoc
:= First
(Component_Associations
(N
));
3640 while Present
(Assoc
) loop
3642 -- If this is a box association, flattening is in general
3643 -- not possible because at this point we cannot tell if the
3644 -- default is static or even exists.
3646 if Box_Present
(Assoc
) then
3650 Choice
:= First
(Choices
(Assoc
));
3652 while Present
(Choice
) loop
3653 if Nkind
(Choice
) = N_Others_Choice
then
3654 Others_Present
:= True;
3665 -- If the low bound is not known at compile time and others is not
3666 -- present we can proceed since the bounds can be obtained from the
3669 -- Note: This case is required in VM platforms since their backends
3670 -- normalize array indexes in the range 0 .. N-1. Hence, if we do
3671 -- not flat an array whose bounds cannot be obtained from the type
3672 -- of the index the backend has no way to properly generate the code.
3673 -- See ACATS c460010 for an example.
3676 or else (not Compile_Time_Known_Value
(Blo
) and then Others_Present
)
3681 -- Determine if set of alternatives is suitable for conversion and
3682 -- build an array containing the values in sequence.
3685 Vals
: array (UI_To_Int
(Lov
) .. UI_To_Int
(Hiv
))
3686 of Node_Id
:= (others => Empty
);
3687 -- The values in the aggregate sorted appropriately
3690 -- Same data as Vals in list form
3693 -- Used to validate Max_Others_Replicate limit
3696 Num
: Int
:= UI_To_Int
(Lov
);
3702 if Present
(Expressions
(N
)) then
3703 Elmt
:= First
(Expressions
(N
));
3704 while Present
(Elmt
) loop
3705 if Nkind
(Elmt
) = N_Aggregate
3706 and then Present
(Next_Index
(Ix
))
3708 not Flatten
(Elmt
, Next_Index
(Ix
), Next_Index
(Ixb
))
3713 Vals
(Num
) := Relocate_Node
(Elmt
);
3720 if No
(Component_Associations
(N
)) then
3724 Elmt
:= First
(Component_Associations
(N
));
3726 if Nkind
(Expression
(Elmt
)) = N_Aggregate
then
3727 if Present
(Next_Index
(Ix
))
3730 (Expression
(Elmt
), Next_Index
(Ix
), Next_Index
(Ixb
))
3736 Component_Loop
: while Present
(Elmt
) loop
3737 Choice
:= First
(Choices
(Elmt
));
3738 Choice_Loop
: while Present
(Choice
) loop
3740 -- If we have an others choice, fill in the missing elements
3741 -- subject to the limit established by Max_Others_Replicate.
3743 if Nkind
(Choice
) = N_Others_Choice
then
3746 for J
in Vals
'Range loop
3747 if No
(Vals
(J
)) then
3748 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
3749 Rep_Count
:= Rep_Count
+ 1;
3751 -- Check for maximum others replication. Note that
3752 -- we skip this test if either of the restrictions
3753 -- No_Elaboration_Code or No_Implicit_Loops is
3754 -- active, if this is a preelaborable unit or
3755 -- a predefined unit, or if the unit must be
3756 -- placed in data memory. This also ensures that
3757 -- predefined units get the same level of constant
3758 -- folding in Ada 95 and Ada 2005, where their
3759 -- categorization has changed.
3762 P
: constant Entity_Id
:=
3763 Cunit_Entity
(Current_Sem_Unit
);
3766 -- Check if duplication OK and if so continue
3769 if Restriction_Active
(No_Elaboration_Code
)
3770 or else Restriction_Active
(No_Implicit_Loops
)
3772 (Ekind
(Current_Scope
) = E_Package
3773 and then Static_Elaboration_Desired
3775 or else Is_Preelaborated
(P
)
3776 or else (Ekind
(P
) = E_Package_Body
3778 Is_Preelaborated
(Spec_Entity
(P
)))
3780 Is_Predefined_File_Name
3781 (Unit_File_Name
(Get_Source_Unit
(P
)))
3785 -- If duplication not OK, then we return False
3786 -- if the replication count is too high
3788 elsif Rep_Count
> Max_Others_Replicate
then
3791 -- Continue on if duplication not OK, but the
3792 -- replication count is not excessive.
3801 exit Component_Loop
;
3803 -- Case of a subtype mark, identifier or expanded name
3805 elsif Is_Entity_Name
(Choice
)
3806 and then Is_Type
(Entity
(Choice
))
3808 Lo
:= Type_Low_Bound
(Etype
(Choice
));
3809 Hi
:= Type_High_Bound
(Etype
(Choice
));
3811 -- Case of subtype indication
3813 elsif Nkind
(Choice
) = N_Subtype_Indication
then
3814 Lo
:= Low_Bound
(Range_Expression
(Constraint
(Choice
)));
3815 Hi
:= High_Bound
(Range_Expression
(Constraint
(Choice
)));
3819 elsif Nkind
(Choice
) = N_Range
then
3820 Lo
:= Low_Bound
(Choice
);
3821 Hi
:= High_Bound
(Choice
);
3823 -- Normal subexpression case
3825 else pragma Assert
(Nkind
(Choice
) in N_Subexpr
);
3826 if not Compile_Time_Known_Value
(Choice
) then
3830 Choice_Index
:= UI_To_Int
(Expr_Value
(Choice
));
3832 if Choice_Index
in Vals
'Range then
3833 Vals
(Choice_Index
) :=
3834 New_Copy_Tree
(Expression
(Elmt
));
3837 -- Choice is statically out-of-range, will be
3838 -- rewritten to raise Constraint_Error.
3846 -- Range cases merge with Lo,Hi set
3848 if not Compile_Time_Known_Value
(Lo
)
3850 not Compile_Time_Known_Value
(Hi
)
3855 for J
in UI_To_Int
(Expr_Value
(Lo
)) ..
3856 UI_To_Int
(Expr_Value
(Hi
))
3858 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
3864 end loop Choice_Loop
;
3867 end loop Component_Loop
;
3869 -- If we get here the conversion is possible
3872 for J
in Vals
'Range loop
3873 Append
(Vals
(J
), Vlist
);
3876 Rewrite
(N
, Make_Aggregate
(Loc
, Expressions
=> Vlist
));
3877 Set_Aggregate_Bounds
(N
, Aggregate_Bounds
(Original_Node
(N
)));
3886 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean is
3893 elsif Nkind
(N
) = N_Aggregate
then
3894 if Present
(Component_Associations
(N
)) then
3898 Elmt
:= First
(Expressions
(N
));
3899 while Present
(Elmt
) loop
3900 if not Is_Flat
(Elmt
, Dims
- 1) then
3914 -- Start of processing for Convert_To_Positional
3917 -- Ada 2005 (AI-287): Do not convert in case of default initialized
3918 -- components because in this case will need to call the corresponding
3921 if Has_Default_Init_Comps
(N
) then
3925 if Is_Flat
(N
, Number_Dimensions
(Typ
)) then
3929 if Is_Bit_Packed_Array
(Typ
) and then not Handle_Bit_Packed
then
3933 -- Do not convert to positional if controlled components are involved
3934 -- since these require special processing
3936 if Has_Controlled_Component
(Typ
) then
3940 Check_Static_Components
;
3942 -- If the size is known, or all the components are static, try to
3943 -- build a fully positional aggregate.
3945 -- The size of the type may not be known for an aggregate with
3946 -- discriminated array components, but if the components are static
3947 -- it is still possible to verify statically that the length is
3948 -- compatible with the upper bound of the type, and therefore it is
3949 -- worth flattening such aggregates as well.
3951 -- For now the back-end expands these aggregates into individual
3952 -- assignments to the target anyway, but it is conceivable that
3953 -- it will eventually be able to treat such aggregates statically???
3955 if Aggr_Size_OK
(N
, Typ
)
3956 and then Flatten
(N
, First_Index
(Typ
), First_Index
(Base_Type
(Typ
)))
3958 if Static_Components
then
3959 Set_Compile_Time_Known_Aggregate
(N
);
3960 Set_Expansion_Delayed
(N
, False);
3963 Analyze_And_Resolve
(N
, Typ
);
3966 -- Is Static_Eaboration_Desired has been specified, diagnose aggregates
3967 -- that will still require initialization code.
3969 if (Ekind
(Current_Scope
) = E_Package
3970 and then Static_Elaboration_Desired
(Current_Scope
))
3971 and then Nkind
(Parent
(N
)) = N_Object_Declaration
3977 if Nkind
(N
) = N_Aggregate
and then Present
(Expressions
(N
)) then
3978 Expr
:= First
(Expressions
(N
));
3979 while Present
(Expr
) loop
3980 if Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
)
3982 (Is_Entity_Name
(Expr
)
3983 and then Ekind
(Entity
(Expr
)) = E_Enumeration_Literal
)
3989 ("non-static object requires elaboration code??", N
);
3996 if Present
(Component_Associations
(N
)) then
3997 Error_Msg_N
("object requires elaboration code??", N
);
4002 end Convert_To_Positional
;
4004 ----------------------------
4005 -- Expand_Array_Aggregate --
4006 ----------------------------
4008 -- Array aggregate expansion proceeds as follows:
4010 -- 1. If requested we generate code to perform all the array aggregate
4011 -- bound checks, specifically
4013 -- (a) Check that the index range defined by aggregate bounds is
4014 -- compatible with corresponding index subtype.
4016 -- (b) If an others choice is present check that no aggregate
4017 -- index is outside the bounds of the index constraint.
4019 -- (c) For multidimensional arrays make sure that all subaggregates
4020 -- corresponding to the same dimension have the same bounds.
4022 -- 2. Check for packed array aggregate which can be converted to a
4023 -- constant so that the aggregate disappears completely.
4025 -- 3. Check case of nested aggregate. Generally nested aggregates are
4026 -- handled during the processing of the parent aggregate.
4028 -- 4. Check if the aggregate can be statically processed. If this is the
4029 -- case pass it as is to Gigi. Note that a necessary condition for
4030 -- static processing is that the aggregate be fully positional.
4032 -- 5. If in place aggregate expansion is possible (i.e. no need to create
4033 -- a temporary) then mark the aggregate as such and return. Otherwise
4034 -- create a new temporary and generate the appropriate initialization
4037 procedure Expand_Array_Aggregate
(N
: Node_Id
) is
4038 Loc
: constant Source_Ptr
:= Sloc
(N
);
4040 Typ
: constant Entity_Id
:= Etype
(N
);
4041 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
4042 -- Typ is the correct constrained array subtype of the aggregate
4043 -- Ctyp is the corresponding component type.
4045 Aggr_Dimension
: constant Pos
:= Number_Dimensions
(Typ
);
4046 -- Number of aggregate index dimensions
4048 Aggr_Low
: array (1 .. Aggr_Dimension
) of Node_Id
;
4049 Aggr_High
: array (1 .. Aggr_Dimension
) of Node_Id
;
4050 -- Low and High bounds of the constraint for each aggregate index
4052 Aggr_Index_Typ
: array (1 .. Aggr_Dimension
) of Entity_Id
;
4053 -- The type of each index
4055 In_Place_Assign_OK_For_Declaration
: Boolean := False;
4056 -- True if we are to generate an in place assignment for a declaration
4058 Maybe_In_Place_OK
: Boolean;
4059 -- If the type is neither controlled nor packed and the aggregate
4060 -- is the expression in an assignment, assignment in place may be
4061 -- possible, provided other conditions are met on the LHS.
4063 Others_Present
: array (1 .. Aggr_Dimension
) of Boolean :=
4065 -- If Others_Present (J) is True, then there is an others choice
4066 -- in one of the sub-aggregates of N at dimension J.
4068 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean;
4069 -- Returns true if an aggregate assignment can be done by the back end
4071 procedure Build_Constrained_Type
(Positional
: Boolean);
4072 -- If the subtype is not static or unconstrained, build a constrained
4073 -- type using the computable sizes of the aggregate and its sub-
4076 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
);
4077 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
4080 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4081 -- Checks that in a multi-dimensional array aggregate all subaggregates
4082 -- corresponding to the same dimension have the same bounds.
4083 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4084 -- corresponding to the sub-aggregate.
4086 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4087 -- Computes the values of array Others_Present. Sub_Aggr is the
4088 -- array sub-aggregate we start the computation from. Dim is the
4089 -- dimension corresponding to the sub-aggregate.
4091 function In_Place_Assign_OK
return Boolean;
4092 -- Simple predicate to determine whether an aggregate assignment can
4093 -- be done in place, because none of the new values can depend on the
4094 -- components of the target of the assignment.
4096 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4097 -- Checks that if an others choice is present in any sub-aggregate no
4098 -- aggregate index is outside the bounds of the index constraint.
4099 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4100 -- corresponding to the sub-aggregate.
4102 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean;
4103 -- In addition to Maybe_In_Place_OK, in order for an aggregate to be
4104 -- built directly into the target of the assignment it must be free
4107 ------------------------------------
4108 -- Aggr_Assignment_OK_For_Backend --
4109 ------------------------------------
4111 -- Backend processing by Gigi/gcc is possible only if all the following
4112 -- conditions are met:
4114 -- 1. N consists of a single OTHERS choice, possibly recursively
4116 -- 2. The array type is not packed
4118 -- 3. The array type has no atomic components
4120 -- 4. The array type has no null ranges (the purpose of this is to
4121 -- avoid a bogus warning for an out-of-range value).
4123 -- 5. The component type is discrete
4125 -- 6. The component size is Storage_Unit or the value is of the form
4126 -- M * (1 + A**1 + A**2 + .. A**(K-1)) where A = 2**(Storage_Unit)
4127 -- and M in 1 .. A-1. This can also be viewed as K occurrences of
4128 -- the 8-bit value M, concatenated together.
4130 -- The ultimate goal is to generate a call to a fast memset routine
4131 -- specifically optimized for the target.
4133 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean is
4136 Expr
: Node_Id
:= N
;
4144 -- Recurse as far as possible to find the innermost component type
4147 while Is_Array_Type
(Ctyp
) loop
4148 if Nkind
(Expr
) /= N_Aggregate
4149 or else not Is_Others_Aggregate
(Expr
)
4154 if Present
(Packed_Array_Impl_Type
(Ctyp
)) then
4158 if Has_Atomic_Components
(Ctyp
) then
4162 Index
:= First_Index
(Ctyp
);
4163 while Present
(Index
) loop
4164 Get_Index_Bounds
(Index
, Low
, High
);
4166 if Is_Null_Range
(Low
, High
) then
4173 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4175 for J
in 1 .. Number_Dimensions
(Ctyp
) - 1 loop
4176 if Nkind
(Expr
) /= N_Aggregate
4177 or else not Is_Others_Aggregate
(Expr
)
4182 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4185 Ctyp
:= Component_Type
(Ctyp
);
4187 if Is_Atomic_Or_VFA
(Ctyp
) then
4192 if not Is_Discrete_Type
(Ctyp
) then
4196 -- The expression needs to be analyzed if True is returned
4198 Analyze_And_Resolve
(Expr
, Ctyp
);
4200 -- The back end uses the Esize as the precision of the type
4202 Nunits
:= UI_To_Int
(Esize
(Ctyp
)) / System_Storage_Unit
;
4208 if not Compile_Time_Known_Value
(Expr
) then
4212 Value
:= Expr_Value
(Expr
);
4214 if Has_Biased_Representation
(Ctyp
) then
4215 Value
:= Value
- Expr_Value
(Type_Low_Bound
(Ctyp
));
4218 -- Values 0 and -1 immediately satisfy the last check
4220 if Value
= Uint_0
or else Value
= Uint_Minus_1
then
4224 -- We need to work with an unsigned value
4227 Value
:= Value
+ 2**(System_Storage_Unit
* Nunits
);
4230 Remainder
:= Value
rem 2**System_Storage_Unit
;
4232 for J
in 1 .. Nunits
- 1 loop
4233 Value
:= Value
/ 2**System_Storage_Unit
;
4235 if Value
rem 2**System_Storage_Unit
/= Remainder
then
4241 end Aggr_Assignment_OK_For_Backend
;
4243 ----------------------------
4244 -- Build_Constrained_Type --
4245 ----------------------------
4247 procedure Build_Constrained_Type
(Positional
: Boolean) is
4248 Loc
: constant Source_Ptr
:= Sloc
(N
);
4249 Agg_Type
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
4252 Typ
: constant Entity_Id
:= Etype
(N
);
4253 Indexes
: constant List_Id
:= New_List
;
4258 -- If the aggregate is purely positional, all its subaggregates
4259 -- have the same size. We collect the dimensions from the first
4260 -- subaggregate at each level.
4265 for D
in 1 .. Number_Dimensions
(Typ
) loop
4266 Sub_Agg
:= First
(Expressions
(Sub_Agg
));
4270 while Present
(Comp
) loop
4277 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
4278 High_Bound
=> Make_Integer_Literal
(Loc
, Num
)));
4282 -- We know the aggregate type is unconstrained and the aggregate
4283 -- is not processable by the back end, therefore not necessarily
4284 -- positional. Retrieve each dimension bounds (computed earlier).
4286 for D
in 1 .. Number_Dimensions
(Typ
) loop
4289 Low_Bound
=> Aggr_Low
(D
),
4290 High_Bound
=> Aggr_High
(D
)));
4295 Make_Full_Type_Declaration
(Loc
,
4296 Defining_Identifier
=> Agg_Type
,
4298 Make_Constrained_Array_Definition
(Loc
,
4299 Discrete_Subtype_Definitions
=> Indexes
,
4300 Component_Definition
=>
4301 Make_Component_Definition
(Loc
,
4302 Aliased_Present
=> False,
4303 Subtype_Indication
=>
4304 New_Occurrence_Of
(Component_Type
(Typ
), Loc
))));
4306 Insert_Action
(N
, Decl
);
4308 Set_Etype
(N
, Agg_Type
);
4309 Set_Is_Itype
(Agg_Type
);
4310 Freeze_Itype
(Agg_Type
, N
);
4311 end Build_Constrained_Type
;
4317 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
) is
4324 Cond
: Node_Id
:= Empty
;
4327 Get_Index_Bounds
(Aggr_Bounds
, Aggr_Lo
, Aggr_Hi
);
4328 Get_Index_Bounds
(Index_Bounds
, Ind_Lo
, Ind_Hi
);
4330 -- Generate the following test:
4332 -- [constraint_error when
4333 -- Aggr_Lo <= Aggr_Hi and then
4334 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
4336 -- As an optimization try to see if some tests are trivially vacuous
4337 -- because we are comparing an expression against itself.
4339 if Aggr_Lo
= Ind_Lo
and then Aggr_Hi
= Ind_Hi
then
4342 elsif Aggr_Hi
= Ind_Hi
then
4345 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4346 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
));
4348 elsif Aggr_Lo
= Ind_Lo
then
4351 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
4352 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Hi
));
4359 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4360 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
)),
4364 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
4365 Right_Opnd
=> Duplicate_Subexpr
(Ind_Hi
)));
4368 if Present
(Cond
) then
4373 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4374 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
)),
4376 Right_Opnd
=> Cond
);
4378 Set_Analyzed
(Left_Opnd
(Left_Opnd
(Cond
)), False);
4379 Set_Analyzed
(Right_Opnd
(Left_Opnd
(Cond
)), False);
4381 Make_Raise_Constraint_Error
(Loc
,
4383 Reason
=> CE_Range_Check_Failed
));
4387 ----------------------------
4388 -- Check_Same_Aggr_Bounds --
4389 ----------------------------
4391 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4392 Sub_Lo
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(Sub_Aggr
));
4393 Sub_Hi
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(Sub_Aggr
));
4394 -- The bounds of this specific sub-aggregate
4396 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
4397 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
4398 -- The bounds of the aggregate for this dimension
4400 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
4401 -- The index type for this dimension.xxx
4403 Cond
: Node_Id
:= Empty
;
4408 -- If index checks are on generate the test
4410 -- [constraint_error when
4411 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
4413 -- As an optimization try to see if some tests are trivially vacuos
4414 -- because we are comparing an expression against itself. Also for
4415 -- the first dimension the test is trivially vacuous because there
4416 -- is just one aggregate for dimension 1.
4418 if Index_Checks_Suppressed
(Ind_Typ
) then
4421 elsif Dim
= 1 or else (Aggr_Lo
= Sub_Lo
and then Aggr_Hi
= Sub_Hi
)
4425 elsif Aggr_Hi
= Sub_Hi
then
4428 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4429 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
));
4431 elsif Aggr_Lo
= Sub_Lo
then
4434 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
4435 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Hi
));
4442 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4443 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
)),
4447 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
4448 Right_Opnd
=> Duplicate_Subexpr
(Sub_Hi
)));
4451 if Present
(Cond
) then
4453 Make_Raise_Constraint_Error
(Loc
,
4455 Reason
=> CE_Length_Check_Failed
));
4458 -- Now look inside the sub-aggregate to see if there is more work
4460 if Dim
< Aggr_Dimension
then
4462 -- Process positional components
4464 if Present
(Expressions
(Sub_Aggr
)) then
4465 Expr
:= First
(Expressions
(Sub_Aggr
));
4466 while Present
(Expr
) loop
4467 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
4472 -- Process component associations
4474 if Present
(Component_Associations
(Sub_Aggr
)) then
4475 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4476 while Present
(Assoc
) loop
4477 Expr
:= Expression
(Assoc
);
4478 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
4483 end Check_Same_Aggr_Bounds
;
4485 ----------------------------
4486 -- Compute_Others_Present --
4487 ----------------------------
4489 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4494 if Present
(Component_Associations
(Sub_Aggr
)) then
4495 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
4497 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
then
4498 Others_Present
(Dim
) := True;
4502 -- Now look inside the sub-aggregate to see if there is more work
4504 if Dim
< Aggr_Dimension
then
4506 -- Process positional components
4508 if Present
(Expressions
(Sub_Aggr
)) then
4509 Expr
:= First
(Expressions
(Sub_Aggr
));
4510 while Present
(Expr
) loop
4511 Compute_Others_Present
(Expr
, Dim
+ 1);
4516 -- Process component associations
4518 if Present
(Component_Associations
(Sub_Aggr
)) then
4519 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4520 while Present
(Assoc
) loop
4521 Expr
:= Expression
(Assoc
);
4522 Compute_Others_Present
(Expr
, Dim
+ 1);
4527 end Compute_Others_Present
;
4529 ------------------------
4530 -- In_Place_Assign_OK --
4531 ------------------------
4533 function In_Place_Assign_OK
return Boolean is
4541 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean;
4542 -- Check recursively that each component of a (sub)aggregate does
4543 -- not depend on the variable being assigned to.
4545 function Safe_Component
(Expr
: Node_Id
) return Boolean;
4546 -- Verify that an expression cannot depend on the variable being
4547 -- assigned to. Room for improvement here (but less than before).
4549 --------------------
4550 -- Safe_Aggregate --
4551 --------------------
4553 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean is
4557 if Present
(Expressions
(Aggr
)) then
4558 Expr
:= First
(Expressions
(Aggr
));
4559 while Present
(Expr
) loop
4560 if Nkind
(Expr
) = N_Aggregate
then
4561 if not Safe_Aggregate
(Expr
) then
4565 elsif not Safe_Component
(Expr
) then
4573 if Present
(Component_Associations
(Aggr
)) then
4574 Expr
:= First
(Component_Associations
(Aggr
));
4575 while Present
(Expr
) loop
4576 if Nkind
(Expression
(Expr
)) = N_Aggregate
then
4577 if not Safe_Aggregate
(Expression
(Expr
)) then
4581 -- If association has a box, no way to determine yet
4582 -- whether default can be assigned in place.
4584 elsif Box_Present
(Expr
) then
4587 elsif not Safe_Component
(Expression
(Expr
)) then
4598 --------------------
4599 -- Safe_Component --
4600 --------------------
4602 function Safe_Component
(Expr
: Node_Id
) return Boolean is
4603 Comp
: Node_Id
:= Expr
;
4605 function Check_Component
(Comp
: Node_Id
) return Boolean;
4606 -- Do the recursive traversal, after copy
4608 ---------------------
4609 -- Check_Component --
4610 ---------------------
4612 function Check_Component
(Comp
: Node_Id
) return Boolean is
4614 if Is_Overloaded
(Comp
) then
4618 return Compile_Time_Known_Value
(Comp
)
4620 or else (Is_Entity_Name
(Comp
)
4621 and then Present
(Entity
(Comp
))
4622 and then No
(Renamed_Object
(Entity
(Comp
))))
4624 or else (Nkind
(Comp
) = N_Attribute_Reference
4625 and then Check_Component
(Prefix
(Comp
)))
4627 or else (Nkind
(Comp
) in N_Binary_Op
4628 and then Check_Component
(Left_Opnd
(Comp
))
4629 and then Check_Component
(Right_Opnd
(Comp
)))
4631 or else (Nkind
(Comp
) in N_Unary_Op
4632 and then Check_Component
(Right_Opnd
(Comp
)))
4634 or else (Nkind
(Comp
) = N_Selected_Component
4635 and then Check_Component
(Prefix
(Comp
)))
4637 or else (Nkind
(Comp
) = N_Unchecked_Type_Conversion
4638 and then Check_Component
(Expression
(Comp
)));
4639 end Check_Component
;
4641 -- Start of processing for Safe_Component
4644 -- If the component appears in an association that may correspond
4645 -- to more than one element, it is not analyzed before expansion
4646 -- into assignments, to avoid side effects. We analyze, but do not
4647 -- resolve the copy, to obtain sufficient entity information for
4648 -- the checks that follow. If component is overloaded we assume
4649 -- an unsafe function call.
4651 if not Analyzed
(Comp
) then
4652 if Is_Overloaded
(Expr
) then
4655 elsif Nkind
(Expr
) = N_Aggregate
4656 and then not Is_Others_Aggregate
(Expr
)
4660 elsif Nkind
(Expr
) = N_Allocator
then
4662 -- For now, too complex to analyze
4667 Comp
:= New_Copy_Tree
(Expr
);
4668 Set_Parent
(Comp
, Parent
(Expr
));
4672 if Nkind
(Comp
) = N_Aggregate
then
4673 return Safe_Aggregate
(Comp
);
4675 return Check_Component
(Comp
);
4679 -- Start of processing for In_Place_Assign_OK
4682 if Present
(Component_Associations
(N
)) then
4684 -- On assignment, sliding can take place, so we cannot do the
4685 -- assignment in place unless the bounds of the aggregate are
4686 -- statically equal to those of the target.
4688 -- If the aggregate is given by an others choice, the bounds are
4689 -- derived from the left-hand side, and the assignment is safe if
4690 -- the expression is.
4692 if Is_Others_Aggregate
(N
) then
4695 (Expression
(First
(Component_Associations
(N
))));
4698 Aggr_In
:= First_Index
(Etype
(N
));
4700 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
4701 Obj_In
:= First_Index
(Etype
(Name
(Parent
(N
))));
4704 -- Context is an allocator. Check bounds of aggregate against
4705 -- given type in qualified expression.
4707 pragma Assert
(Nkind
(Parent
(Parent
(N
))) = N_Allocator
);
4709 First_Index
(Etype
(Entity
(Subtype_Mark
(Parent
(N
)))));
4712 while Present
(Aggr_In
) loop
4713 Get_Index_Bounds
(Aggr_In
, Aggr_Lo
, Aggr_Hi
);
4714 Get_Index_Bounds
(Obj_In
, Obj_Lo
, Obj_Hi
);
4716 if not Compile_Time_Known_Value
(Aggr_Lo
)
4717 or else not Compile_Time_Known_Value
(Aggr_Hi
)
4718 or else not Compile_Time_Known_Value
(Obj_Lo
)
4719 or else not Compile_Time_Known_Value
(Obj_Hi
)
4720 or else Expr_Value
(Aggr_Lo
) /= Expr_Value
(Obj_Lo
)
4721 or else Expr_Value
(Aggr_Hi
) /= Expr_Value
(Obj_Hi
)
4726 Next_Index
(Aggr_In
);
4727 Next_Index
(Obj_In
);
4731 -- Now check the component values themselves
4733 return Safe_Aggregate
(N
);
4734 end In_Place_Assign_OK
;
4740 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4741 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
4742 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
4743 -- The bounds of the aggregate for this dimension
4745 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
4746 -- The index type for this dimension
4748 Need_To_Check
: Boolean := False;
4750 Choices_Lo
: Node_Id
:= Empty
;
4751 Choices_Hi
: Node_Id
:= Empty
;
4752 -- The lowest and highest discrete choices for a named sub-aggregate
4754 Nb_Choices
: Int
:= -1;
4755 -- The number of discrete non-others choices in this sub-aggregate
4757 Nb_Elements
: Uint
:= Uint_0
;
4758 -- The number of elements in a positional aggregate
4760 Cond
: Node_Id
:= Empty
;
4767 -- Check if we have an others choice. If we do make sure that this
4768 -- sub-aggregate contains at least one element in addition to the
4771 if Range_Checks_Suppressed
(Ind_Typ
) then
4772 Need_To_Check
:= False;
4774 elsif Present
(Expressions
(Sub_Aggr
))
4775 and then Present
(Component_Associations
(Sub_Aggr
))
4777 Need_To_Check
:= True;
4779 elsif Present
(Component_Associations
(Sub_Aggr
)) then
4780 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
4782 if Nkind
(First
(Choices
(Assoc
))) /= N_Others_Choice
then
4783 Need_To_Check
:= False;
4786 -- Count the number of discrete choices. Start with -1 because
4787 -- the others choice does not count.
4789 -- Is there some reason we do not use List_Length here ???
4792 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4793 while Present
(Assoc
) loop
4794 Choice
:= First
(Choices
(Assoc
));
4795 while Present
(Choice
) loop
4796 Nb_Choices
:= Nb_Choices
+ 1;
4803 -- If there is only an others choice nothing to do
4805 Need_To_Check
:= (Nb_Choices
> 0);
4809 Need_To_Check
:= False;
4812 -- If we are dealing with a positional sub-aggregate with an others
4813 -- choice then compute the number or positional elements.
4815 if Need_To_Check
and then Present
(Expressions
(Sub_Aggr
)) then
4816 Expr
:= First
(Expressions
(Sub_Aggr
));
4817 Nb_Elements
:= Uint_0
;
4818 while Present
(Expr
) loop
4819 Nb_Elements
:= Nb_Elements
+ 1;
4823 -- If the aggregate contains discrete choices and an others choice
4824 -- compute the smallest and largest discrete choice values.
4826 elsif Need_To_Check
then
4827 Compute_Choices_Lo_And_Choices_Hi
: declare
4829 Table
: Case_Table_Type
(1 .. Nb_Choices
);
4830 -- Used to sort all the different choice values
4837 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4838 while Present
(Assoc
) loop
4839 Choice
:= First
(Choices
(Assoc
));
4840 while Present
(Choice
) loop
4841 if Nkind
(Choice
) = N_Others_Choice
then
4845 Get_Index_Bounds
(Choice
, Low
, High
);
4846 Table
(J
).Choice_Lo
:= Low
;
4847 Table
(J
).Choice_Hi
:= High
;
4856 -- Sort the discrete choices
4858 Sort_Case_Table
(Table
);
4860 Choices_Lo
:= Table
(1).Choice_Lo
;
4861 Choices_Hi
:= Table
(Nb_Choices
).Choice_Hi
;
4862 end Compute_Choices_Lo_And_Choices_Hi
;
4865 -- If no others choice in this sub-aggregate, or the aggregate
4866 -- comprises only an others choice, nothing to do.
4868 if not Need_To_Check
then
4871 -- If we are dealing with an aggregate containing an others choice
4872 -- and positional components, we generate the following test:
4874 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
4875 -- Ind_Typ'Pos (Aggr_Hi)
4877 -- raise Constraint_Error;
4880 elsif Nb_Elements
> Uint_0
then
4886 Make_Attribute_Reference
(Loc
,
4887 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
4888 Attribute_Name
=> Name_Pos
,
4891 (Duplicate_Subexpr_Move_Checks
(Aggr_Lo
))),
4892 Right_Opnd
=> Make_Integer_Literal
(Loc
, Nb_Elements
- 1)),
4895 Make_Attribute_Reference
(Loc
,
4896 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
4897 Attribute_Name
=> Name_Pos
,
4898 Expressions
=> New_List
(
4899 Duplicate_Subexpr_Move_Checks
(Aggr_Hi
))));
4901 -- If we are dealing with an aggregate containing an others choice
4902 -- and discrete choices we generate the following test:
4904 -- [constraint_error when
4905 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
4912 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Choices_Lo
),
4913 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
)),
4917 Left_Opnd
=> Duplicate_Subexpr
(Choices_Hi
),
4918 Right_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
)));
4921 if Present
(Cond
) then
4923 Make_Raise_Constraint_Error
(Loc
,
4925 Reason
=> CE_Length_Check_Failed
));
4926 -- Questionable reason code, shouldn't that be a
4927 -- CE_Range_Check_Failed ???
4930 -- Now look inside the sub-aggregate to see if there is more work
4932 if Dim
< Aggr_Dimension
then
4934 -- Process positional components
4936 if Present
(Expressions
(Sub_Aggr
)) then
4937 Expr
:= First
(Expressions
(Sub_Aggr
));
4938 while Present
(Expr
) loop
4939 Others_Check
(Expr
, Dim
+ 1);
4944 -- Process component associations
4946 if Present
(Component_Associations
(Sub_Aggr
)) then
4947 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4948 while Present
(Assoc
) loop
4949 Expr
:= Expression
(Assoc
);
4950 Others_Check
(Expr
, Dim
+ 1);
4957 -------------------------
4958 -- Safe_Left_Hand_Side --
4959 -------------------------
4961 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean is
4962 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean;
4963 -- If the left-hand side includes an indexed component, check that
4964 -- the indexes are free of side-effect.
4970 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean is
4972 if Is_Entity_Name
(Indx
) then
4975 elsif Nkind
(Indx
) = N_Integer_Literal
then
4978 elsif Nkind
(Indx
) = N_Function_Call
4979 and then Is_Entity_Name
(Name
(Indx
))
4980 and then Has_Pragma_Pure_Function
(Entity
(Name
(Indx
)))
4984 elsif Nkind
(Indx
) = N_Type_Conversion
4985 and then Is_Safe_Index
(Expression
(Indx
))
4994 -- Start of processing for Safe_Left_Hand_Side
4997 if Is_Entity_Name
(N
) then
5000 elsif Nkind_In
(N
, N_Explicit_Dereference
, N_Selected_Component
)
5001 and then Safe_Left_Hand_Side
(Prefix
(N
))
5005 elsif Nkind
(N
) = N_Indexed_Component
5006 and then Safe_Left_Hand_Side
(Prefix
(N
))
5007 and then Is_Safe_Index
(First
(Expressions
(N
)))
5011 elsif Nkind
(N
) = N_Unchecked_Type_Conversion
then
5012 return Safe_Left_Hand_Side
(Expression
(N
));
5017 end Safe_Left_Hand_Side
;
5022 -- Holds the temporary aggregate value
5025 -- Holds the declaration of Tmp
5027 Aggr_Code
: List_Id
;
5028 Parent_Node
: Node_Id
;
5029 Parent_Kind
: Node_Kind
;
5031 -- Start of processing for Expand_Array_Aggregate
5034 -- Do not touch the special aggregates of attributes used for Asm calls
5036 if Is_RTE
(Ctyp
, RE_Asm_Input_Operand
)
5037 or else Is_RTE
(Ctyp
, RE_Asm_Output_Operand
)
5041 -- Do not expand an aggregate for an array type which contains tasks if
5042 -- the aggregate is associated with an unexpanded return statement of a
5043 -- build-in-place function. The aggregate is expanded when the related
5044 -- return statement (rewritten into an extended return) is processed.
5045 -- This delay ensures that any temporaries and initialization code
5046 -- generated for the aggregate appear in the proper return block and
5047 -- use the correct _chain and _master.
5049 elsif Has_Task
(Base_Type
(Etype
(N
)))
5050 and then Nkind
(Parent
(N
)) = N_Simple_Return_Statement
5051 and then Is_Build_In_Place_Function
5052 (Return_Applies_To
(Return_Statement_Entity
(Parent
(N
))))
5056 -- Do not attempt expansion if error already detected. We may reach this
5057 -- point in spite of previous errors when compiling with -gnatq, to
5058 -- force all possible errors (this is the usual ACATS mode).
5060 elsif Error_Posted
(N
) then
5064 -- If the semantic analyzer has determined that aggregate N will raise
5065 -- Constraint_Error at run time, then the aggregate node has been
5066 -- replaced with an N_Raise_Constraint_Error node and we should
5069 pragma Assert
(not Raises_Constraint_Error
(N
));
5073 -- Check that the index range defined by aggregate bounds is
5074 -- compatible with corresponding index subtype.
5076 Index_Compatibility_Check
: declare
5077 Aggr_Index_Range
: Node_Id
:= First_Index
(Typ
);
5078 -- The current aggregate index range
5080 Index_Constraint
: Node_Id
:= First_Index
(Etype
(Typ
));
5081 -- The corresponding index constraint against which we have to
5082 -- check the above aggregate index range.
5085 Compute_Others_Present
(N
, 1);
5087 for J
in 1 .. Aggr_Dimension
loop
5088 -- There is no need to emit a check if an others choice is present
5089 -- for this array aggregate dimension since in this case one of
5090 -- N's sub-aggregates has taken its bounds from the context and
5091 -- these bounds must have been checked already. In addition all
5092 -- sub-aggregates corresponding to the same dimension must all
5093 -- have the same bounds (checked in (c) below).
5095 if not Range_Checks_Suppressed
(Etype
(Index_Constraint
))
5096 and then not Others_Present
(J
)
5098 -- We don't use Checks.Apply_Range_Check here because it emits
5099 -- a spurious check. Namely it checks that the range defined by
5100 -- the aggregate bounds is non empty. But we know this already
5103 Check_Bounds
(Aggr_Index_Range
, Index_Constraint
);
5106 -- Save the low and high bounds of the aggregate index as well as
5107 -- the index type for later use in checks (b) and (c) below.
5109 Aggr_Low
(J
) := Low_Bound
(Aggr_Index_Range
);
5110 Aggr_High
(J
) := High_Bound
(Aggr_Index_Range
);
5112 Aggr_Index_Typ
(J
) := Etype
(Index_Constraint
);
5114 Next_Index
(Aggr_Index_Range
);
5115 Next_Index
(Index_Constraint
);
5117 end Index_Compatibility_Check
;
5121 -- If an others choice is present check that no aggregate index is
5122 -- outside the bounds of the index constraint.
5124 Others_Check
(N
, 1);
5128 -- For multidimensional arrays make sure that all subaggregates
5129 -- corresponding to the same dimension have the same bounds.
5131 if Aggr_Dimension
> 1 then
5132 Check_Same_Aggr_Bounds
(N
, 1);
5137 -- If we have a default component value, or simple initialization is
5138 -- required for the component type, then we replace <> in component
5139 -- associations by the required default value.
5142 Default_Val
: Node_Id
;
5146 if (Present
(Default_Aspect_Component_Value
(Typ
))
5147 or else Needs_Simple_Initialization
(Ctyp
))
5148 and then Present
(Component_Associations
(N
))
5150 Assoc
:= First
(Component_Associations
(N
));
5151 while Present
(Assoc
) loop
5152 if Nkind
(Assoc
) = N_Component_Association
5153 and then Box_Present
(Assoc
)
5155 Set_Box_Present
(Assoc
, False);
5157 if Present
(Default_Aspect_Component_Value
(Typ
)) then
5158 Default_Val
:= Default_Aspect_Component_Value
(Typ
);
5160 Default_Val
:= Get_Simple_Init_Val
(Ctyp
, N
);
5163 Set_Expression
(Assoc
, New_Copy_Tree
(Default_Val
));
5164 Analyze_And_Resolve
(Expression
(Assoc
), Ctyp
);
5174 -- Here we test for is packed array aggregate that we can handle at
5175 -- compile time. If so, return with transformation done. Note that we do
5176 -- this even if the aggregate is nested, because once we have done this
5177 -- processing, there is no more nested aggregate.
5179 if Packed_Array_Aggregate_Handled
(N
) then
5183 -- At this point we try to convert to positional form
5185 if Ekind
(Current_Scope
) = E_Package
5186 and then Static_Elaboration_Desired
(Current_Scope
)
5188 Convert_To_Positional
(N
, Max_Others_Replicate
=> 100);
5190 Convert_To_Positional
(N
);
5193 -- if the result is no longer an aggregate (e.g. it may be a string
5194 -- literal, or a temporary which has the needed value), then we are
5195 -- done, since there is no longer a nested aggregate.
5197 if Nkind
(N
) /= N_Aggregate
then
5200 -- We are also done if the result is an analyzed aggregate, indicating
5201 -- that Convert_To_Positional succeeded and reanalyzed the rewritten
5204 elsif Analyzed
(N
) and then N
/= Original_Node
(N
) then
5208 -- If all aggregate components are compile-time known and the aggregate
5209 -- has been flattened, nothing left to do. The same occurs if the
5210 -- aggregate is used to initialize the components of a statically
5211 -- allocated dispatch table.
5213 if Compile_Time_Known_Aggregate
(N
)
5214 or else Is_Static_Dispatch_Table_Aggregate
(N
)
5216 Set_Expansion_Delayed
(N
, False);
5220 -- Now see if back end processing is possible
5222 if Backend_Processing_Possible
(N
) then
5224 -- If the aggregate is static but the constraints are not, build
5225 -- a static subtype for the aggregate, so that Gigi can place it
5226 -- in static memory. Perform an unchecked_conversion to the non-
5227 -- static type imposed by the context.
5230 Itype
: constant Entity_Id
:= Etype
(N
);
5232 Needs_Type
: Boolean := False;
5235 Index
:= First_Index
(Itype
);
5236 while Present
(Index
) loop
5237 if not Is_OK_Static_Subtype
(Etype
(Index
)) then
5246 Build_Constrained_Type
(Positional
=> True);
5247 Rewrite
(N
, Unchecked_Convert_To
(Itype
, N
));
5257 -- Delay expansion for nested aggregates: it will be taken care of
5258 -- when the parent aggregate is expanded.
5260 Parent_Node
:= Parent
(N
);
5261 Parent_Kind
:= Nkind
(Parent_Node
);
5263 if Parent_Kind
= N_Qualified_Expression
then
5264 Parent_Node
:= Parent
(Parent_Node
);
5265 Parent_Kind
:= Nkind
(Parent_Node
);
5268 if Parent_Kind
= N_Aggregate
5269 or else Parent_Kind
= N_Extension_Aggregate
5270 or else Parent_Kind
= N_Component_Association
5271 or else (Parent_Kind
= N_Object_Declaration
5272 and then Needs_Finalization
(Typ
))
5273 or else (Parent_Kind
= N_Assignment_Statement
5274 and then Inside_Init_Proc
)
5276 if Static_Array_Aggregate
(N
)
5277 or else Compile_Time_Known_Aggregate
(N
)
5279 Set_Expansion_Delayed
(N
, False);
5282 Set_Expansion_Delayed
(N
);
5289 -- Look if in place aggregate expansion is possible
5291 -- For object declarations we build the aggregate in place, unless
5292 -- the array is bit-packed or the component is controlled.
5294 -- For assignments we do the assignment in place if all the component
5295 -- associations have compile-time known values. For other cases we
5296 -- create a temporary. The analysis for safety of on-line assignment
5297 -- is delicate, i.e. we don't know how to do it fully yet ???
5299 -- For allocators we assign to the designated object in place if the
5300 -- aggregate meets the same conditions as other in-place assignments.
5301 -- In this case the aggregate may not come from source but was created
5302 -- for default initialization, e.g. with Initialize_Scalars.
5304 if Requires_Transient_Scope
(Typ
) then
5305 Establish_Transient_Scope
5306 (N
, Sec_Stack
=> Has_Controlled_Component
(Typ
));
5309 if Has_Default_Init_Comps
(N
) then
5310 Maybe_In_Place_OK
:= False;
5312 elsif Is_Bit_Packed_Array
(Typ
)
5313 or else Has_Controlled_Component
(Typ
)
5315 Maybe_In_Place_OK
:= False;
5318 Maybe_In_Place_OK
:=
5319 (Nkind
(Parent
(N
)) = N_Assignment_Statement
5320 and then In_Place_Assign_OK
)
5323 (Nkind
(Parent
(Parent
(N
))) = N_Allocator
5324 and then In_Place_Assign_OK
);
5327 -- If this is an array of tasks, it will be expanded into build-in-place
5328 -- assignments. Build an activation chain for the tasks now.
5330 if Has_Task
(Etype
(N
)) then
5331 Build_Activation_Chain_Entity
(N
);
5334 -- Perform in-place expansion of aggregate in an object declaration.
5335 -- Note: actions generated for the aggregate will be captured in an
5336 -- expression-with-actions statement so that they can be transferred
5337 -- to freeze actions later if there is an address clause for the
5338 -- object. (Note: we don't use a block statement because this would
5339 -- cause generated freeze nodes to be elaborated in the wrong scope).
5341 -- Should document these individual tests ???
5343 if not Has_Default_Init_Comps
(N
)
5344 and then Comes_From_Source
(Parent_Node
)
5345 and then Parent_Kind
= N_Object_Declaration
5347 Must_Slide
(Etype
(Defining_Identifier
(Parent_Node
)), Typ
)
5348 and then N
= Expression
(Parent_Node
)
5349 and then not Is_Bit_Packed_Array
(Typ
)
5350 and then not Has_Controlled_Component
(Typ
)
5352 In_Place_Assign_OK_For_Declaration
:= True;
5353 Tmp
:= Defining_Identifier
(Parent
(N
));
5354 Set_No_Initialization
(Parent
(N
));
5355 Set_Expression
(Parent
(N
), Empty
);
5357 -- Set kind and type of the entity, for use in the analysis
5358 -- of the subsequent assignments. If the nominal type is not
5359 -- constrained, build a subtype from the known bounds of the
5360 -- aggregate. If the declaration has a subtype mark, use it,
5361 -- otherwise use the itype of the aggregate.
5363 Set_Ekind
(Tmp
, E_Variable
);
5365 if not Is_Constrained
(Typ
) then
5366 Build_Constrained_Type
(Positional
=> False);
5368 elsif Is_Entity_Name
(Object_Definition
(Parent
(N
)))
5369 and then Is_Constrained
(Entity
(Object_Definition
(Parent
(N
))))
5371 Set_Etype
(Tmp
, Entity
(Object_Definition
(Parent
(N
))));
5374 Set_Size_Known_At_Compile_Time
(Typ
, False);
5375 Set_Etype
(Tmp
, Typ
);
5378 elsif Maybe_In_Place_OK
5379 and then Nkind
(Parent
(N
)) = N_Qualified_Expression
5380 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
5382 Set_Expansion_Delayed
(N
);
5385 -- In the remaining cases the aggregate is the RHS of an assignment
5387 elsif Maybe_In_Place_OK
5388 and then Safe_Left_Hand_Side
(Name
(Parent
(N
)))
5390 Tmp
:= Name
(Parent
(N
));
5392 if Etype
(Tmp
) /= Etype
(N
) then
5393 Apply_Length_Check
(N
, Etype
(Tmp
));
5395 if Nkind
(N
) = N_Raise_Constraint_Error
then
5397 -- Static error, nothing further to expand
5403 -- If a slice assignment has an aggregate with a single others_choice,
5404 -- the assignment can be done in place even if bounds are not static,
5405 -- by converting it into a loop over the discrete range of the slice.
5407 elsif Maybe_In_Place_OK
5408 and then Nkind
(Name
(Parent
(N
))) = N_Slice
5409 and then Is_Others_Aggregate
(N
)
5411 Tmp
:= Name
(Parent
(N
));
5413 -- Set type of aggregate to be type of lhs in assignment, in order
5414 -- to suppress redundant length checks.
5416 Set_Etype
(N
, Etype
(Tmp
));
5420 -- In place aggregate expansion is not possible
5423 Maybe_In_Place_OK
:= False;
5424 Tmp
:= Make_Temporary
(Loc
, 'A', N
);
5426 Make_Object_Declaration
(Loc
,
5427 Defining_Identifier
=> Tmp
,
5428 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
5429 Set_No_Initialization
(Tmp_Decl
, True);
5431 -- If we are within a loop, the temporary will be pushed on the
5432 -- stack at each iteration. If the aggregate is the expression for an
5433 -- allocator, it will be immediately copied to the heap and can
5434 -- be reclaimed at once. We create a transient scope around the
5435 -- aggregate for this purpose.
5437 if Ekind
(Current_Scope
) = E_Loop
5438 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
5440 Establish_Transient_Scope
(N
, False);
5443 Insert_Action
(N
, Tmp_Decl
);
5446 -- Construct and insert the aggregate code. We can safely suppress index
5447 -- checks because this code is guaranteed not to raise CE on index
5448 -- checks. However we should *not* suppress all checks.
5454 if Nkind
(Tmp
) = N_Defining_Identifier
then
5455 Target
:= New_Occurrence_Of
(Tmp
, Loc
);
5458 if Has_Default_Init_Comps
(N
) then
5460 -- Ada 2005 (AI-287): This case has not been analyzed???
5462 raise Program_Error
;
5465 -- Name in assignment is explicit dereference
5467 Target
:= New_Copy
(Tmp
);
5470 -- If we are to generate an in place assignment for a declaration or
5471 -- an assignment statement, and the assignment can be done directly
5472 -- by the back end, then do not expand further.
5474 -- ??? We can also do that if in place expansion is not possible but
5475 -- then we could go into an infinite recursion.
5477 if (In_Place_Assign_OK_For_Declaration
or else Maybe_In_Place_OK
)
5478 and then VM_Target
= No_VM
5479 and then not AAMP_On_Target
5480 and then not Generate_SCIL
5481 and then not Possible_Bit_Aligned_Component
(Target
)
5482 and then not Is_Possibly_Unaligned_Slice
(Target
)
5483 and then Aggr_Assignment_OK_For_Backend
(N
)
5485 if Maybe_In_Place_OK
then
5491 Make_Assignment_Statement
(Loc
,
5493 Expression
=> New_Copy
(N
)));
5497 Build_Array_Aggr_Code
(N
,
5499 Index
=> First_Index
(Typ
),
5501 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
5504 -- Save the last assignment statement associated with the aggregate
5505 -- when building a controlled object. This reference is utilized by
5506 -- the finalization machinery when marking an object as successfully
5509 if Needs_Finalization
(Typ
)
5510 and then Is_Entity_Name
(Target
)
5511 and then Present
(Entity
(Target
))
5512 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
5514 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
5518 -- If the aggregate is the expression in a declaration, the expanded
5519 -- code must be inserted after it. The defining entity might not come
5520 -- from source if this is part of an inlined body, but the declaration
5523 if Comes_From_Source
(Tmp
)
5525 (Nkind
(Parent
(N
)) = N_Object_Declaration
5526 and then Comes_From_Source
(Parent
(N
))
5527 and then Tmp
= Defining_Entity
(Parent
(N
)))
5530 Node_After
: constant Node_Id
:= Next
(Parent_Node
);
5533 Insert_Actions_After
(Parent_Node
, Aggr_Code
);
5535 if Parent_Kind
= N_Object_Declaration
then
5536 Collect_Initialization_Statements
5537 (Obj
=> Tmp
, N
=> Parent_Node
, Node_After
=> Node_After
);
5542 Insert_Actions
(N
, Aggr_Code
);
5545 -- If the aggregate has been assigned in place, remove the original
5548 if Nkind
(Parent
(N
)) = N_Assignment_Statement
5549 and then Maybe_In_Place_OK
5551 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
5553 elsif Nkind
(Parent
(N
)) /= N_Object_Declaration
5554 or else Tmp
/= Defining_Identifier
(Parent
(N
))
5556 Rewrite
(N
, New_Occurrence_Of
(Tmp
, Loc
));
5557 Analyze_And_Resolve
(N
, Typ
);
5559 end Expand_Array_Aggregate
;
5561 ------------------------
5562 -- Expand_N_Aggregate --
5563 ------------------------
5565 procedure Expand_N_Aggregate
(N
: Node_Id
) is
5567 -- Record aggregate case
5569 if Is_Record_Type
(Etype
(N
)) then
5570 Expand_Record_Aggregate
(N
);
5572 -- Array aggregate case
5575 -- A special case, if we have a string subtype with bounds 1 .. N,
5576 -- where N is known at compile time, and the aggregate is of the
5577 -- form (others => 'x'), with a single choice and no expressions,
5578 -- and N is less than 80 (an arbitrary limit for now), then replace
5579 -- the aggregate by the equivalent string literal (but do not mark
5580 -- it as static since it is not).
5582 -- Note: this entire circuit is redundant with respect to code in
5583 -- Expand_Array_Aggregate that collapses others choices to positional
5584 -- form, but there are two problems with that circuit:
5586 -- a) It is limited to very small cases due to ill-understood
5587 -- interactions with bootstrapping. That limit is removed by
5588 -- use of the No_Implicit_Loops restriction.
5590 -- b) It incorrectly ends up with the resulting expressions being
5591 -- considered static when they are not. For example, the
5592 -- following test should fail:
5594 -- pragma Restrictions (No_Implicit_Loops);
5595 -- package NonSOthers4 is
5596 -- B : constant String (1 .. 6) := (others => 'A');
5597 -- DH : constant String (1 .. 8) := B & "BB";
5599 -- pragma Export (C, X, Link_Name => DH);
5602 -- But it succeeds (DH looks static to pragma Export)
5604 -- To be sorted out ???
5606 if Present
(Component_Associations
(N
)) then
5608 CA
: constant Node_Id
:= First
(Component_Associations
(N
));
5609 MX
: constant := 80;
5612 if Nkind
(First
(Choices
(CA
))) = N_Others_Choice
5613 and then Nkind
(Expression
(CA
)) = N_Character_Literal
5614 and then No
(Expressions
(N
))
5617 T
: constant Entity_Id
:= Etype
(N
);
5618 X
: constant Node_Id
:= First_Index
(T
);
5619 EC
: constant Node_Id
:= Expression
(CA
);
5620 CV
: constant Uint
:= Char_Literal_Value
(EC
);
5621 CC
: constant Int
:= UI_To_Int
(CV
);
5624 if Nkind
(X
) = N_Range
5625 and then Compile_Time_Known_Value
(Low_Bound
(X
))
5626 and then Expr_Value
(Low_Bound
(X
)) = 1
5627 and then Compile_Time_Known_Value
(High_Bound
(X
))
5630 Hi
: constant Uint
:= Expr_Value
(High_Bound
(X
));
5636 for J
in 1 .. UI_To_Int
(Hi
) loop
5637 Store_String_Char
(Char_Code
(CC
));
5641 Make_String_Literal
(Sloc
(N
),
5642 Strval
=> End_String
));
5644 if CC
>= Int
(2 ** 16) then
5645 Set_Has_Wide_Wide_Character
(N
);
5646 elsif CC
>= Int
(2 ** 8) then
5647 Set_Has_Wide_Character
(N
);
5650 Analyze_And_Resolve
(N
, T
);
5651 Set_Is_Static_Expression
(N
, False);
5661 -- Not that special case, so normal expansion of array aggregate
5663 Expand_Array_Aggregate
(N
);
5667 when RE_Not_Available
=>
5669 end Expand_N_Aggregate
;
5671 ----------------------------------
5672 -- Expand_N_Extension_Aggregate --
5673 ----------------------------------
5675 -- If the ancestor part is an expression, add a component association for
5676 -- the parent field. If the type of the ancestor part is not the direct
5677 -- parent of the expected type, build recursively the needed ancestors.
5678 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
5679 -- ration for a temporary of the expected type, followed by individual
5680 -- assignments to the given components.
5682 procedure Expand_N_Extension_Aggregate
(N
: Node_Id
) is
5683 Loc
: constant Source_Ptr
:= Sloc
(N
);
5684 A
: constant Node_Id
:= Ancestor_Part
(N
);
5685 Typ
: constant Entity_Id
:= Etype
(N
);
5688 -- If the ancestor is a subtype mark, an init proc must be called
5689 -- on the resulting object which thus has to be materialized in
5692 if Is_Entity_Name
(A
) and then Is_Type
(Entity
(A
)) then
5693 Convert_To_Assignments
(N
, Typ
);
5695 -- The extension aggregate is transformed into a record aggregate
5696 -- of the following form (c1 and c2 are inherited components)
5698 -- (Exp with c3 => a, c4 => b)
5699 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c3 => a, c4 => b)
5704 if Tagged_Type_Expansion
then
5705 Expand_Record_Aggregate
(N
,
5708 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
),
5711 -- No tag is needed in the case of a VM
5714 Expand_Record_Aggregate
(N
, Parent_Expr
=> A
);
5719 when RE_Not_Available
=>
5721 end Expand_N_Extension_Aggregate
;
5723 -----------------------------
5724 -- Expand_Record_Aggregate --
5725 -----------------------------
5727 procedure Expand_Record_Aggregate
5729 Orig_Tag
: Node_Id
:= Empty
;
5730 Parent_Expr
: Node_Id
:= Empty
)
5732 Loc
: constant Source_Ptr
:= Sloc
(N
);
5733 Comps
: constant List_Id
:= Component_Associations
(N
);
5734 Typ
: constant Entity_Id
:= Etype
(N
);
5735 Base_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
5737 Static_Components
: Boolean := True;
5738 -- Flag to indicate whether all components are compile-time known,
5739 -- and the aggregate can be constructed statically and handled by
5742 function Compile_Time_Known_Composite_Value
(N
: Node_Id
) return Boolean;
5743 -- Returns true if N is an expression of composite type which can be
5744 -- fully evaluated at compile time without raising constraint error.
5745 -- Such expressions can be passed as is to Gigi without any expansion.
5747 -- This returns true for N_Aggregate with Compile_Time_Known_Aggregate
5748 -- set and constants whose expression is such an aggregate, recursively.
5750 function Component_Not_OK_For_Backend
return Boolean;
5751 -- Check for presence of a component which makes it impossible for the
5752 -- backend to process the aggregate, thus requiring the use of a series
5753 -- of assignment statements. Cases checked for are a nested aggregate
5754 -- needing Late_Expansion, the presence of a tagged component which may
5755 -- need tag adjustment, and a bit unaligned component reference.
5757 -- We also force expansion into assignments if a component is of a
5758 -- mutable type (including a private type with discriminants) because
5759 -- in that case the size of the component to be copied may be smaller
5760 -- than the side of the target, and there is no simple way for gigi
5761 -- to compute the size of the object to be copied.
5763 -- NOTE: This is part of the ongoing work to define precisely the
5764 -- interface between front-end and back-end handling of aggregates.
5765 -- In general it is desirable to pass aggregates as they are to gigi,
5766 -- in order to minimize elaboration code. This is one case where the
5767 -- semantics of Ada complicate the analysis and lead to anomalies in
5768 -- the gcc back-end if the aggregate is not expanded into assignments.
5770 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean;
5771 -- If any ancestor of the current type is private, the aggregate
5772 -- cannot be built in place. We cannot rely on Has_Private_Ancestor,
5773 -- because it will not be set when type and its parent are in the
5774 -- same scope, and the parent component needs expansion.
5776 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
;
5777 -- For nested aggregates return the ultimate enclosing aggregate; for
5778 -- non-nested aggregates return N.
5780 ----------------------------------------
5781 -- Compile_Time_Known_Composite_Value --
5782 ----------------------------------------
5784 function Compile_Time_Known_Composite_Value
5785 (N
: Node_Id
) return Boolean
5788 -- If we have an entity name, then see if it is the name of a
5789 -- constant and if so, test the corresponding constant value.
5791 if Is_Entity_Name
(N
) then
5793 E
: constant Entity_Id
:= Entity
(N
);
5796 if Ekind
(E
) /= E_Constant
then
5799 V
:= Constant_Value
(E
);
5801 and then Compile_Time_Known_Composite_Value
(V
);
5805 -- We have a value, see if it is compile time known
5808 if Nkind
(N
) = N_Aggregate
then
5809 return Compile_Time_Known_Aggregate
(N
);
5812 -- All other types of values are not known at compile time
5817 end Compile_Time_Known_Composite_Value
;
5819 ----------------------------------
5820 -- Component_Not_OK_For_Backend --
5821 ----------------------------------
5823 function Component_Not_OK_For_Backend
return Boolean is
5833 while Present
(C
) loop
5835 -- If the component has box initialization, expansion is needed
5836 -- and component is not ready for backend.
5838 if Box_Present
(C
) then
5842 if Nkind
(Expression
(C
)) = N_Qualified_Expression
then
5843 Expr_Q
:= Expression
(Expression
(C
));
5845 Expr_Q
:= Expression
(C
);
5848 -- Return true if the aggregate has any associations for tagged
5849 -- components that may require tag adjustment.
5851 -- These are cases where the source expression may have a tag that
5852 -- could differ from the component tag (e.g., can occur for type
5853 -- conversions and formal parameters). (Tag adjustment not needed
5854 -- if VM_Target because object tags are implicit in the machine.)
5856 if Is_Tagged_Type
(Etype
(Expr_Q
))
5857 and then (Nkind
(Expr_Q
) = N_Type_Conversion
5858 or else (Is_Entity_Name
(Expr_Q
)
5860 Ekind
(Entity
(Expr_Q
)) in Formal_Kind
))
5861 and then Tagged_Type_Expansion
5863 Static_Components
:= False;
5866 elsif Is_Delayed_Aggregate
(Expr_Q
) then
5867 Static_Components
:= False;
5870 elsif Possible_Bit_Aligned_Component
(Expr_Q
) then
5871 Static_Components
:= False;
5875 if Is_Elementary_Type
(Etype
(Expr_Q
)) then
5876 if not Compile_Time_Known_Value
(Expr_Q
) then
5877 Static_Components
:= False;
5880 elsif not Compile_Time_Known_Composite_Value
(Expr_Q
) then
5881 Static_Components
:= False;
5883 if Is_Private_Type
(Etype
(Expr_Q
))
5884 and then Has_Discriminants
(Etype
(Expr_Q
))
5894 end Component_Not_OK_For_Backend
;
5896 -----------------------------------
5897 -- Has_Visible_Private_Ancestor --
5898 -----------------------------------
5900 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean is
5901 R
: constant Entity_Id
:= Root_Type
(Id
);
5902 T1
: Entity_Id
:= Id
;
5906 if Is_Private_Type
(T1
) then
5916 end Has_Visible_Private_Ancestor
;
5918 -------------------------
5919 -- Top_Level_Aggregate --
5920 -------------------------
5922 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
is
5927 while Present
(Parent
(Aggr
))
5928 and then Nkind_In
(Parent
(Aggr
), N_Component_Association
,
5931 Aggr
:= Parent
(Aggr
);
5935 end Top_Level_Aggregate
;
5939 Top_Level_Aggr
: constant Node_Id
:= Top_Level_Aggregate
(N
);
5940 Tag_Value
: Node_Id
;
5944 -- Start of processing for Expand_Record_Aggregate
5947 -- If the aggregate is to be assigned to an atomic/VFA variable, we have
5948 -- to prevent a piecemeal assignment even if the aggregate is to be
5949 -- expanded. We create a temporary for the aggregate, and assign the
5950 -- temporary instead, so that the back end can generate an atomic move
5953 if Is_Atomic_VFA_Aggregate
(N
) then
5956 -- No special management required for aggregates used to initialize
5957 -- statically allocated dispatch tables
5959 elsif Is_Static_Dispatch_Table_Aggregate
(N
) then
5963 -- Ada 2005 (AI-318-2): We need to convert to assignments if components
5964 -- are build-in-place function calls. The assignments will each turn
5965 -- into a build-in-place function call. If components are all static,
5966 -- we can pass the aggregate to the backend regardless of limitedness.
5968 -- Extension aggregates, aggregates in extended return statements, and
5969 -- aggregates for C++ imported types must be expanded.
5971 if Ada_Version
>= Ada_2005
and then Is_Limited_View
(Typ
) then
5972 if not Nkind_In
(Parent
(N
), N_Object_Declaration
,
5973 N_Component_Association
)
5975 Convert_To_Assignments
(N
, Typ
);
5977 elsif Nkind
(N
) = N_Extension_Aggregate
5978 or else Convention
(Typ
) = Convention_CPP
5980 Convert_To_Assignments
(N
, Typ
);
5982 elsif not Size_Known_At_Compile_Time
(Typ
)
5983 or else Component_Not_OK_For_Backend
5984 or else not Static_Components
5986 Convert_To_Assignments
(N
, Typ
);
5989 Set_Compile_Time_Known_Aggregate
(N
);
5990 Set_Expansion_Delayed
(N
, False);
5993 -- Gigi doesn't properly handle temporaries of variable size so we
5994 -- generate it in the front-end
5996 elsif not Size_Known_At_Compile_Time
(Typ
)
5997 and then Tagged_Type_Expansion
5999 Convert_To_Assignments
(N
, Typ
);
6001 -- An aggregate used to initialize a controlled object must be turned
6002 -- into component assignments as the components themselves may require
6003 -- finalization actions such as adjustment.
6005 elsif Needs_Finalization
(Typ
) then
6006 Convert_To_Assignments
(N
, Typ
);
6008 -- Ada 2005 (AI-287): In case of default initialized components we
6009 -- convert the aggregate into assignments.
6011 elsif Has_Default_Init_Comps
(N
) then
6012 Convert_To_Assignments
(N
, Typ
);
6016 elsif Component_Not_OK_For_Backend
then
6017 Convert_To_Assignments
(N
, Typ
);
6019 -- If an ancestor is private, some components are not inherited and we
6020 -- cannot expand into a record aggregate.
6022 elsif Has_Visible_Private_Ancestor
(Typ
) then
6023 Convert_To_Assignments
(N
, Typ
);
6025 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
6026 -- is not able to handle the aggregate for Late_Request.
6028 elsif Is_Tagged_Type
(Typ
) and then Has_Discriminants
(Typ
) then
6029 Convert_To_Assignments
(N
, Typ
);
6031 -- If the tagged types covers interface types we need to initialize all
6032 -- hidden components containing pointers to secondary dispatch tables.
6034 elsif Is_Tagged_Type
(Typ
) and then Has_Interfaces
(Typ
) then
6035 Convert_To_Assignments
(N
, Typ
);
6037 -- If some components are mutable, the size of the aggregate component
6038 -- may be distinct from the default size of the type component, so
6039 -- we need to expand to insure that the back-end copies the proper
6040 -- size of the data. However, if the aggregate is the initial value of
6041 -- a constant, the target is immutable and might be built statically
6042 -- if components are appropriate.
6044 elsif Has_Mutable_Components
(Typ
)
6046 (Nkind
(Parent
(Top_Level_Aggr
)) /= N_Object_Declaration
6047 or else not Constant_Present
(Parent
(Top_Level_Aggr
))
6048 or else not Static_Components
)
6050 Convert_To_Assignments
(N
, Typ
);
6052 -- If the type involved has bit aligned components, then we are not sure
6053 -- that the back end can handle this case correctly.
6055 elsif Type_May_Have_Bit_Aligned_Components
(Typ
) then
6056 Convert_To_Assignments
(N
, Typ
);
6058 -- In all other cases, build a proper aggregate to be handled by gigi
6061 if Nkind
(N
) = N_Aggregate
then
6063 -- If the aggregate is static and can be handled by the back-end,
6064 -- nothing left to do.
6066 if Static_Components
then
6067 Set_Compile_Time_Known_Aggregate
(N
);
6068 Set_Expansion_Delayed
(N
, False);
6072 -- If no discriminants, nothing special to do
6074 if not Has_Discriminants
(Typ
) then
6077 -- Case of discriminants present
6079 elsif Is_Derived_Type
(Typ
) then
6081 -- For untagged types, non-stored discriminants are replaced
6082 -- with stored discriminants, which are the ones that gigi uses
6083 -- to describe the type and its components.
6085 Generate_Aggregate_For_Derived_Type
: declare
6086 Constraints
: constant List_Id
:= New_List
;
6087 First_Comp
: Node_Id
;
6088 Discriminant
: Entity_Id
;
6090 Num_Disc
: Int
:= 0;
6091 Num_Gird
: Int
:= 0;
6093 procedure Prepend_Stored_Values
(T
: Entity_Id
);
6094 -- Scan the list of stored discriminants of the type, and add
6095 -- their values to the aggregate being built.
6097 ---------------------------
6098 -- Prepend_Stored_Values --
6099 ---------------------------
6101 procedure Prepend_Stored_Values
(T
: Entity_Id
) is
6103 Discriminant
:= First_Stored_Discriminant
(T
);
6104 while Present
(Discriminant
) loop
6106 Make_Component_Association
(Loc
,
6108 New_List
(New_Occurrence_Of
(Discriminant
, Loc
)),
6112 (Get_Discriminant_Value
6115 Discriminant_Constraint
(Typ
))));
6117 if No
(First_Comp
) then
6118 Prepend_To
(Component_Associations
(N
), New_Comp
);
6120 Insert_After
(First_Comp
, New_Comp
);
6123 First_Comp
:= New_Comp
;
6124 Next_Stored_Discriminant
(Discriminant
);
6126 end Prepend_Stored_Values
;
6128 -- Start of processing for Generate_Aggregate_For_Derived_Type
6131 -- Remove the associations for the discriminant of derived type
6133 First_Comp
:= First
(Component_Associations
(N
));
6134 while Present
(First_Comp
) loop
6138 if Ekind
(Entity
(First
(Choices
(Comp
)))) = E_Discriminant
6141 Num_Disc
:= Num_Disc
+ 1;
6145 -- Insert stored discriminant associations in the correct
6146 -- order. If there are more stored discriminants than new
6147 -- discriminants, there is at least one new discriminant that
6148 -- constrains more than one of the stored discriminants. In
6149 -- this case we need to construct a proper subtype of the
6150 -- parent type, in order to supply values to all the
6151 -- components. Otherwise there is one-one correspondence
6152 -- between the constraints and the stored discriminants.
6154 First_Comp
:= Empty
;
6156 Discriminant
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6157 while Present
(Discriminant
) loop
6158 Num_Gird
:= Num_Gird
+ 1;
6159 Next_Stored_Discriminant
(Discriminant
);
6162 -- Case of more stored discriminants than new discriminants
6164 if Num_Gird
> Num_Disc
then
6166 -- Create a proper subtype of the parent type, which is the
6167 -- proper implementation type for the aggregate, and convert
6168 -- it to the intended target type.
6170 Discriminant
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6171 while Present
(Discriminant
) loop
6174 (Get_Discriminant_Value
6177 Discriminant_Constraint
(Typ
)));
6178 Append
(New_Comp
, Constraints
);
6179 Next_Stored_Discriminant
(Discriminant
);
6183 Make_Subtype_Declaration
(Loc
,
6184 Defining_Identifier
=> Make_Temporary
(Loc
, 'T'),
6185 Subtype_Indication
=>
6186 Make_Subtype_Indication
(Loc
,
6188 New_Occurrence_Of
(Etype
(Base_Type
(Typ
)), Loc
),
6190 Make_Index_Or_Discriminant_Constraint
6191 (Loc
, Constraints
)));
6193 Insert_Action
(N
, Decl
);
6194 Prepend_Stored_Values
(Base_Type
(Typ
));
6196 Set_Etype
(N
, Defining_Identifier
(Decl
));
6199 Rewrite
(N
, Unchecked_Convert_To
(Typ
, N
));
6202 -- Case where we do not have fewer new discriminants than
6203 -- stored discriminants, so in this case we can simply use the
6204 -- stored discriminants of the subtype.
6207 Prepend_Stored_Values
(Typ
);
6209 end Generate_Aggregate_For_Derived_Type
;
6212 if Is_Tagged_Type
(Typ
) then
6214 -- In the tagged case, _parent and _tag component must be created
6216 -- Reset Null_Present unconditionally. Tagged records always have
6217 -- at least one field (the tag or the parent).
6219 Set_Null_Record_Present
(N
, False);
6221 -- When the current aggregate comes from the expansion of an
6222 -- extension aggregate, the parent expr is replaced by an
6223 -- aggregate formed by selected components of this expr.
6225 if Present
(Parent_Expr
) and then Is_Empty_List
(Comps
) then
6226 Comp
:= First_Component_Or_Discriminant
(Typ
);
6227 while Present
(Comp
) loop
6229 -- Skip all expander-generated components
6231 if not Comes_From_Source
(Original_Record_Component
(Comp
))
6237 Make_Selected_Component
(Loc
,
6239 Unchecked_Convert_To
(Typ
,
6240 Duplicate_Subexpr
(Parent_Expr
, True)),
6241 Selector_Name
=> New_Occurrence_Of
(Comp
, Loc
));
6244 Make_Component_Association
(Loc
,
6246 New_List
(New_Occurrence_Of
(Comp
, Loc
)),
6247 Expression
=> New_Comp
));
6249 Analyze_And_Resolve
(New_Comp
, Etype
(Comp
));
6252 Next_Component_Or_Discriminant
(Comp
);
6256 -- Compute the value for the Tag now, if the type is a root it
6257 -- will be included in the aggregate right away, otherwise it will
6258 -- be propagated to the parent aggregate.
6260 if Present
(Orig_Tag
) then
6261 Tag_Value
:= Orig_Tag
;
6262 elsif not Tagged_Type_Expansion
then
6267 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
);
6270 -- For a derived type, an aggregate for the parent is formed with
6271 -- all the inherited components.
6273 if Is_Derived_Type
(Typ
) then
6276 First_Comp
: Node_Id
;
6277 Parent_Comps
: List_Id
;
6278 Parent_Aggr
: Node_Id
;
6279 Parent_Name
: Node_Id
;
6282 -- Remove the inherited component association from the
6283 -- aggregate and store them in the parent aggregate
6285 First_Comp
:= First
(Component_Associations
(N
));
6286 Parent_Comps
:= New_List
;
6287 while Present
(First_Comp
)
6289 Scope
(Original_Record_Component
6290 (Entity
(First
(Choices
(First_Comp
))))) /=
6296 Append
(Comp
, Parent_Comps
);
6300 Make_Aggregate
(Loc
,
6301 Component_Associations
=> Parent_Comps
);
6302 Set_Etype
(Parent_Aggr
, Etype
(Base_Type
(Typ
)));
6304 -- Find the _parent component
6306 Comp
:= First_Component
(Typ
);
6307 while Chars
(Comp
) /= Name_uParent
loop
6308 Comp
:= Next_Component
(Comp
);
6311 Parent_Name
:= New_Occurrence_Of
(Comp
, Loc
);
6313 -- Insert the parent aggregate
6315 Prepend_To
(Component_Associations
(N
),
6316 Make_Component_Association
(Loc
,
6317 Choices
=> New_List
(Parent_Name
),
6318 Expression
=> Parent_Aggr
));
6320 -- Expand recursively the parent propagating the right Tag
6322 Expand_Record_Aggregate
6323 (Parent_Aggr
, Tag_Value
, Parent_Expr
);
6325 -- The ancestor part may be a nested aggregate that has
6326 -- delayed expansion: recheck now.
6328 if Component_Not_OK_For_Backend
then
6329 Convert_To_Assignments
(N
, Typ
);
6333 -- For a root type, the tag component is added (unless compiling
6334 -- for the VMs, where tags are implicit).
6336 elsif Tagged_Type_Expansion
then
6338 Tag_Name
: constant Node_Id
:=
6339 New_Occurrence_Of
(First_Tag_Component
(Typ
), Loc
);
6340 Typ_Tag
: constant Entity_Id
:= RTE
(RE_Tag
);
6341 Conv_Node
: constant Node_Id
:=
6342 Unchecked_Convert_To
(Typ_Tag
, Tag_Value
);
6345 Set_Etype
(Conv_Node
, Typ_Tag
);
6346 Prepend_To
(Component_Associations
(N
),
6347 Make_Component_Association
(Loc
,
6348 Choices
=> New_List
(Tag_Name
),
6349 Expression
=> Conv_Node
));
6355 end Expand_Record_Aggregate
;
6357 ----------------------------
6358 -- Has_Default_Init_Comps --
6359 ----------------------------
6361 function Has_Default_Init_Comps
(N
: Node_Id
) return Boolean is
6362 Comps
: constant List_Id
:= Component_Associations
(N
);
6367 pragma Assert
(Nkind_In
(N
, N_Aggregate
, N_Extension_Aggregate
));
6373 if Has_Self_Reference
(N
) then
6377 -- Check if any direct component has default initialized components
6380 while Present
(C
) loop
6381 if Box_Present
(C
) then
6388 -- Recursive call in case of aggregate expression
6391 while Present
(C
) loop
6392 Expr
:= Expression
(C
);
6395 and then Nkind_In
(Expr
, N_Aggregate
, N_Extension_Aggregate
)
6396 and then Has_Default_Init_Comps
(Expr
)
6405 end Has_Default_Init_Comps
;
6407 --------------------------
6408 -- Is_Delayed_Aggregate --
6409 --------------------------
6411 function Is_Delayed_Aggregate
(N
: Node_Id
) return Boolean is
6412 Node
: Node_Id
:= N
;
6413 Kind
: Node_Kind
:= Nkind
(Node
);
6416 if Kind
= N_Qualified_Expression
then
6417 Node
:= Expression
(Node
);
6418 Kind
:= Nkind
(Node
);
6421 if not Nkind_In
(Kind
, N_Aggregate
, N_Extension_Aggregate
) then
6424 return Expansion_Delayed
(Node
);
6426 end Is_Delayed_Aggregate
;
6428 ----------------------------------------
6429 -- Is_Static_Dispatch_Table_Aggregate --
6430 ----------------------------------------
6432 function Is_Static_Dispatch_Table_Aggregate
(N
: Node_Id
) return Boolean is
6433 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
6436 return Static_Dispatch_Tables
6437 and then Tagged_Type_Expansion
6438 and then RTU_Loaded
(Ada_Tags
)
6440 -- Avoid circularity when rebuilding the compiler
6442 and then Cunit_Entity
(Get_Source_Unit
(N
)) /= RTU_Entity
(Ada_Tags
)
6443 and then (Typ
= RTE
(RE_Dispatch_Table_Wrapper
)
6445 Typ
= RTE
(RE_Address_Array
)
6447 Typ
= RTE
(RE_Type_Specific_Data
)
6449 Typ
= RTE
(RE_Tag_Table
)
6451 (RTE_Available
(RE_Interface_Data
)
6452 and then Typ
= RTE
(RE_Interface_Data
))
6454 (RTE_Available
(RE_Interfaces_Array
)
6455 and then Typ
= RTE
(RE_Interfaces_Array
))
6457 (RTE_Available
(RE_Interface_Data_Element
)
6458 and then Typ
= RTE
(RE_Interface_Data_Element
)));
6459 end Is_Static_Dispatch_Table_Aggregate
;
6461 -----------------------------
6462 -- Is_Two_Dim_Packed_Array --
6463 -----------------------------
6465 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean is
6466 C
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
6468 return Number_Dimensions
(Typ
) = 2
6469 and then Is_Bit_Packed_Array
(Typ
)
6470 and then (C
= 1 or else C
= 2 or else C
= 4);
6471 end Is_Two_Dim_Packed_Array
;
6473 --------------------
6474 -- Late_Expansion --
6475 --------------------
6477 function Late_Expansion
6480 Target
: Node_Id
) return List_Id
6482 Aggr_Code
: List_Id
;
6485 if Is_Record_Type
(Etype
(N
)) then
6486 Aggr_Code
:= Build_Record_Aggr_Code
(N
, Typ
, Target
);
6488 else pragma Assert
(Is_Array_Type
(Etype
(N
)));
6490 Build_Array_Aggr_Code
6492 Ctype
=> Component_Type
(Etype
(N
)),
6493 Index
=> First_Index
(Typ
),
6495 Scalar_Comp
=> Is_Scalar_Type
(Component_Type
(Typ
)),
6496 Indexes
=> No_List
);
6499 -- Save the last assignment statement associated with the aggregate
6500 -- when building a controlled object. This reference is utilized by
6501 -- the finalization machinery when marking an object as successfully
6504 if Needs_Finalization
(Typ
)
6505 and then Is_Entity_Name
(Target
)
6506 and then Present
(Entity
(Target
))
6507 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
6509 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
6515 ----------------------------------
6516 -- Make_OK_Assignment_Statement --
6517 ----------------------------------
6519 function Make_OK_Assignment_Statement
6522 Expression
: Node_Id
) return Node_Id
6525 Set_Assignment_OK
(Name
);
6526 return Make_Assignment_Statement
(Sloc
, Name
, Expression
);
6527 end Make_OK_Assignment_Statement
;
6529 -----------------------
6530 -- Number_Of_Choices --
6531 -----------------------
6533 function Number_Of_Choices
(N
: Node_Id
) return Nat
is
6537 Nb_Choices
: Nat
:= 0;
6540 if Present
(Expressions
(N
)) then
6544 Assoc
:= First
(Component_Associations
(N
));
6545 while Present
(Assoc
) loop
6546 Choice
:= First
(Choices
(Assoc
));
6547 while Present
(Choice
) loop
6548 if Nkind
(Choice
) /= N_Others_Choice
then
6549 Nb_Choices
:= Nb_Choices
+ 1;
6559 end Number_Of_Choices
;
6561 ------------------------------------
6562 -- Packed_Array_Aggregate_Handled --
6563 ------------------------------------
6565 -- The current version of this procedure will handle at compile time
6566 -- any array aggregate that meets these conditions:
6568 -- One and two dimensional, bit packed
6569 -- Underlying packed type is modular type
6570 -- Bounds are within 32-bit Int range
6571 -- All bounds and values are static
6573 -- Note: for now, in the 2-D case, we only handle component sizes of
6574 -- 1, 2, 4 (cases where an integral number of elements occupies a byte).
6576 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean is
6577 Loc
: constant Source_Ptr
:= Sloc
(N
);
6578 Typ
: constant Entity_Id
:= Etype
(N
);
6579 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
6581 Not_Handled
: exception;
6582 -- Exception raised if this aggregate cannot be handled
6585 -- Handle one- or two dimensional bit packed array
6587 if not Is_Bit_Packed_Array
(Typ
)
6588 or else Number_Dimensions
(Typ
) > 2
6593 -- If two-dimensional, check whether it can be folded, and transformed
6594 -- into a one-dimensional aggregate for the Packed_Array_Impl_Type of
6595 -- the original type.
6597 if Number_Dimensions
(Typ
) = 2 then
6598 return Two_Dim_Packed_Array_Handled
(N
);
6601 if not Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
)) then
6605 if not Is_Scalar_Type
(Component_Type
(Typ
))
6606 and then Has_Non_Standard_Rep
(Component_Type
(Typ
))
6612 Csiz
: constant Nat
:= UI_To_Int
(Component_Size
(Typ
));
6616 -- Bounds of index type
6620 -- Values of bounds if compile time known
6622 function Get_Component_Val
(N
: Node_Id
) return Uint
;
6623 -- Given a expression value N of the component type Ctyp, returns a
6624 -- value of Csiz (component size) bits representing this value. If
6625 -- the value is non-static or any other reason exists why the value
6626 -- cannot be returned, then Not_Handled is raised.
6628 -----------------------
6629 -- Get_Component_Val --
6630 -----------------------
6632 function Get_Component_Val
(N
: Node_Id
) return Uint
is
6636 -- We have to analyze the expression here before doing any further
6637 -- processing here. The analysis of such expressions is deferred
6638 -- till expansion to prevent some problems of premature analysis.
6640 Analyze_And_Resolve
(N
, Ctyp
);
6642 -- Must have a compile time value. String literals have to be
6643 -- converted into temporaries as well, because they cannot easily
6644 -- be converted into their bit representation.
6646 if not Compile_Time_Known_Value
(N
)
6647 or else Nkind
(N
) = N_String_Literal
6652 Val
:= Expr_Rep_Value
(N
);
6654 -- Adjust for bias, and strip proper number of bits
6656 if Has_Biased_Representation
(Ctyp
) then
6657 Val
:= Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
6660 return Val
mod Uint_2
** Csiz
;
6661 end Get_Component_Val
;
6663 -- Here we know we have a one dimensional bit packed array
6666 Get_Index_Bounds
(First_Index
(Typ
), Lo
, Hi
);
6668 -- Cannot do anything if bounds are dynamic
6670 if not Compile_Time_Known_Value
(Lo
)
6672 not Compile_Time_Known_Value
(Hi
)
6677 -- Or are silly out of range of int bounds
6679 Lob
:= Expr_Value
(Lo
);
6680 Hib
:= Expr_Value
(Hi
);
6682 if not UI_Is_In_Int_Range
(Lob
)
6684 not UI_Is_In_Int_Range
(Hib
)
6689 -- At this stage we have a suitable aggregate for handling at compile
6690 -- time. The only remaining checks are that the values of expressions
6691 -- in the aggregate are compile-time known (checks are performed by
6692 -- Get_Component_Val), and that any subtypes or ranges are statically
6695 -- If the aggregate is not fully positional at this stage, then
6696 -- convert it to positional form. Either this will fail, in which
6697 -- case we can do nothing, or it will succeed, in which case we have
6698 -- succeeded in handling the aggregate and transforming it into a
6699 -- modular value, or it will stay an aggregate, in which case we
6700 -- have failed to create a packed value for it.
6702 if Present
(Component_Associations
(N
)) then
6703 Convert_To_Positional
6704 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
6705 return Nkind
(N
) /= N_Aggregate
;
6708 -- Otherwise we are all positional, so convert to proper value
6711 Lov
: constant Int
:= UI_To_Int
(Lob
);
6712 Hiv
: constant Int
:= UI_To_Int
(Hib
);
6714 Len
: constant Nat
:= Int
'Max (0, Hiv
- Lov
+ 1);
6715 -- The length of the array (number of elements)
6717 Aggregate_Val
: Uint
;
6718 -- Value of aggregate. The value is set in the low order bits of
6719 -- this value. For the little-endian case, the values are stored
6720 -- from low-order to high-order and for the big-endian case the
6721 -- values are stored from high-order to low-order. Note that gigi
6722 -- will take care of the conversions to left justify the value in
6723 -- the big endian case (because of left justified modular type
6724 -- processing), so we do not have to worry about that here.
6727 -- Integer literal for resulting constructed value
6730 -- Shift count from low order for next value
6733 -- Shift increment for loop
6736 -- Next expression from positional parameters of aggregate
6738 Left_Justified
: Boolean;
6739 -- Set True if we are filling the high order bits of the target
6740 -- value (i.e. the value is left justified).
6743 -- For little endian, we fill up the low order bits of the target
6744 -- value. For big endian we fill up the high order bits of the
6745 -- target value (which is a left justified modular value).
6747 Left_Justified
:= Bytes_Big_Endian
;
6749 -- Switch justification if using -gnatd8
6751 if Debug_Flag_8
then
6752 Left_Justified
:= not Left_Justified
;
6755 -- Switch justfification if reverse storage order
6757 if Reverse_Storage_Order
(Base_Type
(Typ
)) then
6758 Left_Justified
:= not Left_Justified
;
6761 if Left_Justified
then
6762 Shift
:= Csiz
* (Len
- 1);
6769 -- Loop to set the values
6772 Aggregate_Val
:= Uint_0
;
6774 Expr
:= First
(Expressions
(N
));
6775 Aggregate_Val
:= Get_Component_Val
(Expr
) * Uint_2
** Shift
;
6777 for J
in 2 .. Len
loop
6778 Shift
:= Shift
+ Incr
;
6781 Aggregate_Val
+ Get_Component_Val
(Expr
) * Uint_2
** Shift
;
6785 -- Now we can rewrite with the proper value
6787 Lit
:= Make_Integer_Literal
(Loc
, Intval
=> Aggregate_Val
);
6788 Set_Print_In_Hex
(Lit
);
6790 -- Construct the expression using this literal. Note that it is
6791 -- important to qualify the literal with its proper modular type
6792 -- since universal integer does not have the required range and
6793 -- also this is a left justified modular type, which is important
6794 -- in the big-endian case.
6797 Unchecked_Convert_To
(Typ
,
6798 Make_Qualified_Expression
(Loc
,
6800 New_Occurrence_Of
(Packed_Array_Impl_Type
(Typ
), Loc
),
6801 Expression
=> Lit
)));
6803 Analyze_And_Resolve
(N
, Typ
);
6811 end Packed_Array_Aggregate_Handled
;
6813 ----------------------------
6814 -- Has_Mutable_Components --
6815 ----------------------------
6817 function Has_Mutable_Components
(Typ
: Entity_Id
) return Boolean is
6821 Comp
:= First_Component
(Typ
);
6822 while Present
(Comp
) loop
6823 if Is_Record_Type
(Etype
(Comp
))
6824 and then Has_Discriminants
(Etype
(Comp
))
6825 and then not Is_Constrained
(Etype
(Comp
))
6830 Next_Component
(Comp
);
6834 end Has_Mutable_Components
;
6836 ------------------------------
6837 -- Initialize_Discriminants --
6838 ------------------------------
6840 procedure Initialize_Discriminants
(N
: Node_Id
; Typ
: Entity_Id
) is
6841 Loc
: constant Source_Ptr
:= Sloc
(N
);
6842 Bas
: constant Entity_Id
:= Base_Type
(Typ
);
6843 Par
: constant Entity_Id
:= Etype
(Bas
);
6844 Decl
: constant Node_Id
:= Parent
(Par
);
6848 if Is_Tagged_Type
(Bas
)
6849 and then Is_Derived_Type
(Bas
)
6850 and then Has_Discriminants
(Par
)
6851 and then Has_Discriminants
(Bas
)
6852 and then Number_Discriminants
(Bas
) /= Number_Discriminants
(Par
)
6853 and then Nkind
(Decl
) = N_Full_Type_Declaration
6854 and then Nkind
(Type_Definition
(Decl
)) = N_Record_Definition
6856 Present
(Variant_Part
(Component_List
(Type_Definition
(Decl
))))
6857 and then Nkind
(N
) /= N_Extension_Aggregate
6860 -- Call init proc to set discriminants.
6861 -- There should eventually be a special procedure for this ???
6863 Ref
:= New_Occurrence_Of
(Defining_Identifier
(N
), Loc
);
6864 Insert_Actions_After
(N
,
6865 Build_Initialization_Call
(Sloc
(N
), Ref
, Typ
));
6867 end Initialize_Discriminants
;
6874 (Obj_Type
: Entity_Id
;
6875 Typ
: Entity_Id
) return Boolean
6877 L1
, L2
, H1
, H2
: Node_Id
;
6880 -- No sliding if the type of the object is not established yet, if it is
6881 -- an unconstrained type whose actual subtype comes from the aggregate,
6882 -- or if the two types are identical.
6884 if not Is_Array_Type
(Obj_Type
) then
6887 elsif not Is_Constrained
(Obj_Type
) then
6890 elsif Typ
= Obj_Type
then
6894 -- Sliding can only occur along the first dimension
6896 Get_Index_Bounds
(First_Index
(Typ
), L1
, H1
);
6897 Get_Index_Bounds
(First_Index
(Obj_Type
), L2
, H2
);
6899 if not Is_OK_Static_Expression
(L1
) or else
6900 not Is_OK_Static_Expression
(L2
) or else
6901 not Is_OK_Static_Expression
(H1
) or else
6902 not Is_OK_Static_Expression
(H2
)
6906 return Expr_Value
(L1
) /= Expr_Value
(L2
)
6908 Expr_Value
(H1
) /= Expr_Value
(H2
);
6913 ----------------------------------
6914 -- Two_Dim_Packed_Array_Handled --
6915 ----------------------------------
6917 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean is
6918 Loc
: constant Source_Ptr
:= Sloc
(N
);
6919 Typ
: constant Entity_Id
:= Etype
(N
);
6920 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
6921 Comp_Size
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
6922 Packed_Array
: constant Entity_Id
:=
6923 Packed_Array_Impl_Type
(Base_Type
(Typ
));
6926 -- Expression in original aggregate
6929 -- One-dimensional subaggregate
6933 -- For now, only deal with cases where an integral number of elements
6934 -- fit in a single byte. This includes the most common boolean case.
6936 if not (Comp_Size
= 1 or else
6937 Comp_Size
= 2 or else
6943 Convert_To_Positional
6944 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
6946 -- Verify that all components are static
6948 if Nkind
(N
) = N_Aggregate
6949 and then Compile_Time_Known_Aggregate
(N
)
6953 -- The aggregate may have been re-analyzed and converted already
6955 elsif Nkind
(N
) /= N_Aggregate
then
6958 -- If component associations remain, the aggregate is not static
6960 elsif Present
(Component_Associations
(N
)) then
6964 One_Dim
:= First
(Expressions
(N
));
6965 while Present
(One_Dim
) loop
6966 if Present
(Component_Associations
(One_Dim
)) then
6970 One_Comp
:= First
(Expressions
(One_Dim
));
6971 while Present
(One_Comp
) loop
6972 if not Is_OK_Static_Expression
(One_Comp
) then
6983 -- Two-dimensional aggregate is now fully positional so pack one
6984 -- dimension to create a static one-dimensional array, and rewrite
6985 -- as an unchecked conversion to the original type.
6988 Byte_Size
: constant Int
:= UI_To_Int
(Component_Size
(Packed_Array
));
6989 -- The packed array type is a byte array
6992 -- Number of components accumulated in current byte
6995 -- Assembled list of packed values for equivalent aggregate
6998 -- integer value of component
7001 -- Step size for packing
7004 -- Endian-dependent start position for packing
7007 -- Current insertion position
7010 -- Component of packed array being assembled.
7017 -- Account for endianness. See corresponding comment in
7018 -- Packed_Array_Aggregate_Handled concerning the following.
7022 xor Reverse_Storage_Order
(Base_Type
(Typ
))
7024 Init_Shift
:= Byte_Size
- Comp_Size
;
7031 -- Iterate over each subaggregate
7033 Shift
:= Init_Shift
;
7034 One_Dim
:= First
(Expressions
(N
));
7035 while Present
(One_Dim
) loop
7036 One_Comp
:= First
(Expressions
(One_Dim
));
7037 while Present
(One_Comp
) loop
7038 if Packed_Num
= Byte_Size
/ Comp_Size
then
7040 -- Byte is complete, add to list of expressions
7042 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
7044 Shift
:= Init_Shift
;
7048 Comp_Val
:= Expr_Rep_Value
(One_Comp
);
7050 -- Adjust for bias, and strip proper number of bits
7052 if Has_Biased_Representation
(Ctyp
) then
7053 Comp_Val
:= Comp_Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
7056 Comp_Val
:= Comp_Val
mod Uint_2
** Comp_Size
;
7057 Val
:= UI_To_Int
(Val
+ Comp_Val
* Uint_2
** Shift
);
7058 Shift
:= Shift
+ Incr
;
7059 One_Comp
:= Next
(One_Comp
);
7060 Packed_Num
:= Packed_Num
+ 1;
7064 One_Dim
:= Next
(One_Dim
);
7067 if Packed_Num
> 0 then
7069 -- Add final incomplete byte if present
7071 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
7075 Unchecked_Convert_To
(Typ
,
7076 Make_Qualified_Expression
(Loc
,
7077 Subtype_Mark
=> New_Occurrence_Of
(Packed_Array
, Loc
),
7078 Expression
=> Make_Aggregate
(Loc
, Expressions
=> Comps
))));
7079 Analyze_And_Resolve
(N
);
7082 end Two_Dim_Packed_Array_Handled
;
7084 ---------------------
7085 -- Sort_Case_Table --
7086 ---------------------
7088 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
) is
7089 L
: constant Int
:= Case_Table
'First;
7090 U
: constant Int
:= Case_Table
'Last;
7098 T
:= Case_Table
(K
+ 1);
7102 and then Expr_Value
(Case_Table
(J
- 1).Choice_Lo
) >
7103 Expr_Value
(T
.Choice_Lo
)
7105 Case_Table
(J
) := Case_Table
(J
- 1);
7109 Case_Table
(J
) := T
;
7112 end Sort_Case_Table
;
7114 ----------------------------
7115 -- Static_Array_Aggregate --
7116 ----------------------------
7118 function Static_Array_Aggregate
(N
: Node_Id
) return Boolean is
7119 Bounds
: constant Node_Id
:= Aggregate_Bounds
(N
);
7121 Typ
: constant Entity_Id
:= Etype
(N
);
7122 Comp_Type
: constant Entity_Id
:= Component_Type
(Typ
);
7129 if Is_Tagged_Type
(Typ
)
7130 or else Is_Controlled
(Typ
)
7131 or else Is_Packed
(Typ
)
7137 and then Nkind
(Bounds
) = N_Range
7138 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
7139 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
7141 Lo
:= Low_Bound
(Bounds
);
7142 Hi
:= High_Bound
(Bounds
);
7144 if No
(Component_Associations
(N
)) then
7146 -- Verify that all components are static integers
7148 Expr
:= First
(Expressions
(N
));
7149 while Present
(Expr
) loop
7150 if Nkind
(Expr
) /= N_Integer_Literal
then
7160 -- We allow only a single named association, either a static
7161 -- range or an others_clause, with a static expression.
7163 Expr
:= First
(Component_Associations
(N
));
7165 if Present
(Expressions
(N
)) then
7168 elsif Present
(Next
(Expr
)) then
7171 elsif Present
(Next
(First
(Choices
(Expr
)))) then
7175 -- The aggregate is static if all components are literals,
7176 -- or else all its components are static aggregates for the
7177 -- component type. We also limit the size of a static aggregate
7178 -- to prevent runaway static expressions.
7180 if Is_Array_Type
(Comp_Type
)
7181 or else Is_Record_Type
(Comp_Type
)
7183 if Nkind
(Expression
(Expr
)) /= N_Aggregate
7185 not Compile_Time_Known_Aggregate
(Expression
(Expr
))
7190 elsif Nkind
(Expression
(Expr
)) /= N_Integer_Literal
then
7194 if not Aggr_Size_OK
(N
, Typ
) then
7198 -- Create a positional aggregate with the right number of
7199 -- copies of the expression.
7201 Agg
:= Make_Aggregate
(Sloc
(N
), New_List
, No_List
);
7203 for I
in UI_To_Int
(Intval
(Lo
)) .. UI_To_Int
(Intval
(Hi
))
7205 Append_To
(Expressions
(Agg
), New_Copy
(Expression
(Expr
)));
7207 -- The copied expression must be analyzed and resolved.
7208 -- Besides setting the type, this ensures that static
7209 -- expressions are appropriately marked as such.
7212 (Last
(Expressions
(Agg
)), Component_Type
(Typ
));
7215 Set_Aggregate_Bounds
(Agg
, Bounds
);
7216 Set_Etype
(Agg
, Typ
);
7219 Set_Compile_Time_Known_Aggregate
(N
);
7228 end Static_Array_Aggregate
;