1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2014, 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 worthwhile to have a higher default value for Max_Others_
243 -- replicate, but aggregates in the compiler make this impossible: the
244 -- compiler bootstrap fails if Max_Others_Replicate is greater than 25.
245 -- This is unexpected ???
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 Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean;
789 function Local_Expr_Value
(E
: Node_Id
) return Uint
;
790 -- These two Local routines are used to replace the corresponding ones
791 -- in sem_eval because while processing the bounds of an aggregate with
792 -- discrete choices whose index type is an enumeration, we build static
793 -- expressions not recognized by Compile_Time_Known_Value as such since
794 -- they have not yet been analyzed and resolved. All the expressions in
795 -- question are things like Index_Base_Name'Val (Const) which we can
796 -- easily recognize as being constant.
802 function Add
(Val
: Int
; To
: Node_Id
) return Node_Id
is
807 U_Val
: constant Uint
:= UI_From_Int
(Val
);
810 -- Note: do not try to optimize the case of Val = 0, because
811 -- we need to build a new node with the proper Sloc value anyway.
813 -- First test if we can do constant folding
815 if Local_Compile_Time_Known_Value
(To
) then
816 U_To
:= Local_Expr_Value
(To
) + Val
;
818 -- Determine if our constant is outside the range of the index.
819 -- If so return an Empty node. This empty node will be caught
820 -- by Empty_Range below.
822 if Compile_Time_Known_Value
(Index_Base_L
)
823 and then U_To
< Expr_Value
(Index_Base_L
)
827 elsif Compile_Time_Known_Value
(Index_Base_H
)
828 and then U_To
> Expr_Value
(Index_Base_H
)
833 Expr_Pos
:= Make_Integer_Literal
(Loc
, U_To
);
834 Set_Is_Static_Expression
(Expr_Pos
);
836 if not Is_Enumeration_Type
(Index_Base
) then
839 -- If we are dealing with enumeration return
840 -- Index_Base'Val (Expr_Pos)
844 Make_Attribute_Reference
846 Prefix
=> Index_Base_Name
,
847 Attribute_Name
=> Name_Val
,
848 Expressions
=> New_List
(Expr_Pos
));
854 -- If we are here no constant folding possible
856 if not Is_Enumeration_Type
(Index_Base
) then
859 Left_Opnd
=> Duplicate_Subexpr
(To
),
860 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
862 -- If we are dealing with enumeration return
863 -- Index_Base'Val (Index_Base'Pos (To) + Val)
867 Make_Attribute_Reference
869 Prefix
=> Index_Base_Name
,
870 Attribute_Name
=> Name_Pos
,
871 Expressions
=> New_List
(Duplicate_Subexpr
(To
)));
876 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
879 Make_Attribute_Reference
881 Prefix
=> Index_Base_Name
,
882 Attribute_Name
=> Name_Val
,
883 Expressions
=> New_List
(Expr_Pos
));
893 function Empty_Range
(L
, H
: Node_Id
) return Boolean is
894 Is_Empty
: Boolean := False;
899 -- First check if L or H were already detected as overflowing the
900 -- index base range type by function Add above. If this is so Add
901 -- returns the empty node.
903 if No
(L
) or else No
(H
) then
910 -- L > H range is empty
916 -- B_L > H range must be empty
922 -- L > B_H range must be empty
926 High
:= Index_Base_H
;
929 if Local_Compile_Time_Known_Value
(Low
)
931 Local_Compile_Time_Known_Value
(High
)
934 UI_Gt
(Local_Expr_Value
(Low
), Local_Expr_Value
(High
));
947 function Equal
(L
, H
: Node_Id
) return Boolean is
952 elsif Local_Compile_Time_Known_Value
(L
)
954 Local_Compile_Time_Known_Value
(H
)
956 return UI_Eq
(Local_Expr_Value
(L
), Local_Expr_Value
(H
));
966 function Gen_Assign
(Ind
: Node_Id
; Expr
: Node_Id
) return List_Id
is
967 L
: constant List_Id
:= New_List
;
970 New_Indexes
: List_Id
;
971 Indexed_Comp
: Node_Id
;
973 Comp_Type
: Entity_Id
:= Empty
;
975 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
;
976 -- Collect insert_actions generated in the construction of a
977 -- loop, and prepend them to the sequence of assignments to
978 -- complete the eventual body of the loop.
980 ----------------------
981 -- Add_Loop_Actions --
982 ----------------------
984 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
is
988 -- Ada 2005 (AI-287): Do nothing else in case of default
989 -- initialized component.
994 elsif Nkind
(Parent
(Expr
)) = N_Component_Association
995 and then Present
(Loop_Actions
(Parent
(Expr
)))
997 Append_List
(Lis
, Loop_Actions
(Parent
(Expr
)));
998 Res
:= Loop_Actions
(Parent
(Expr
));
999 Set_Loop_Actions
(Parent
(Expr
), No_List
);
1005 end Add_Loop_Actions
;
1007 -- Start of processing for Gen_Assign
1010 if No
(Indexes
) then
1011 New_Indexes
:= New_List
;
1013 New_Indexes
:= New_Copy_List_Tree
(Indexes
);
1016 Append_To
(New_Indexes
, Ind
);
1018 if Present
(Next_Index
(Index
)) then
1021 Build_Array_Aggr_Code
1024 Index
=> Next_Index
(Index
),
1026 Scalar_Comp
=> Scalar_Comp
,
1027 Indexes
=> New_Indexes
));
1030 -- If we get here then we are at a bottom-level (sub-)aggregate
1034 (Make_Indexed_Component
(Loc
,
1035 Prefix
=> New_Copy_Tree
(Into
),
1036 Expressions
=> New_Indexes
));
1038 Set_Assignment_OK
(Indexed_Comp
);
1040 -- Ada 2005 (AI-287): In case of default initialized component, Expr
1041 -- is not present (and therefore we also initialize Expr_Q to empty).
1045 elsif Nkind
(Expr
) = N_Qualified_Expression
then
1046 Expr_Q
:= Expression
(Expr
);
1051 if Present
(Etype
(N
)) and then Etype
(N
) /= Any_Composite
then
1052 Comp_Type
:= Component_Type
(Etype
(N
));
1053 pragma Assert
(Comp_Type
= Ctype
); -- AI-287
1055 elsif Present
(Next
(First
(New_Indexes
))) then
1057 -- Ada 2005 (AI-287): Do nothing in case of default initialized
1058 -- component because we have received the component type in
1059 -- the formal parameter Ctype.
1061 -- ??? Some assert pragmas have been added to check if this new
1062 -- formal can be used to replace this code in all cases.
1064 if Present
(Expr
) then
1066 -- This is a multidimensional array. Recover the component type
1067 -- from the outermost aggregate, because subaggregates do not
1068 -- have an assigned type.
1075 while Present
(P
) loop
1076 if Nkind
(P
) = N_Aggregate
1077 and then Present
(Etype
(P
))
1079 Comp_Type
:= Component_Type
(Etype
(P
));
1087 pragma Assert
(Comp_Type
= Ctype
); -- AI-287
1092 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
1093 -- default initialized components (otherwise Expr_Q is not present).
1096 and then Nkind_In
(Expr_Q
, N_Aggregate
, N_Extension_Aggregate
)
1098 -- At this stage the Expression may not have been analyzed yet
1099 -- because the array aggregate code has not been updated to use
1100 -- the Expansion_Delayed flag and avoid analysis altogether to
1101 -- solve the same problem (see Resolve_Aggr_Expr). So let us do
1102 -- the analysis of non-array aggregates now in order to get the
1103 -- value of Expansion_Delayed flag for the inner aggregate ???
1105 if Present
(Comp_Type
) and then not Is_Array_Type
(Comp_Type
) then
1106 Analyze_And_Resolve
(Expr_Q
, Comp_Type
);
1109 if Is_Delayed_Aggregate
(Expr_Q
) then
1111 -- This is either a subaggregate of a multidimensional array,
1112 -- or a component of an array type whose component type is
1113 -- also an array. In the latter case, the expression may have
1114 -- component associations that provide different bounds from
1115 -- those of the component type, and sliding must occur. Instead
1116 -- of decomposing the current aggregate assignment, force the
1117 -- re-analysis of the assignment, so that a temporary will be
1118 -- generated in the usual fashion, and sliding will take place.
1120 if Nkind
(Parent
(N
)) = N_Assignment_Statement
1121 and then Is_Array_Type
(Comp_Type
)
1122 and then Present
(Component_Associations
(Expr_Q
))
1123 and then Must_Slide
(Comp_Type
, Etype
(Expr_Q
))
1125 Set_Expansion_Delayed
(Expr_Q
, False);
1126 Set_Analyzed
(Expr_Q
, False);
1131 Late_Expansion
(Expr_Q
, Etype
(Expr_Q
), Indexed_Comp
));
1136 -- Ada 2005 (AI-287): In case of default initialized component, call
1137 -- the initialization subprogram associated with the component type.
1138 -- If the component type is an access type, add an explicit null
1139 -- assignment, because for the back-end there is an initialization
1140 -- present for the whole aggregate, and no default initialization
1143 -- In addition, if the component type is controlled, we must call
1144 -- its Initialize procedure explicitly, because there is no explicit
1145 -- object creation that will invoke it otherwise.
1148 if Present
(Base_Init_Proc
(Base_Type
(Ctype
)))
1149 or else Has_Task
(Base_Type
(Ctype
))
1152 Build_Initialization_Call
(Loc
,
1153 Id_Ref
=> Indexed_Comp
,
1155 With_Default_Init
=> True));
1157 elsif Is_Access_Type
(Ctype
) then
1159 Make_Assignment_Statement
(Loc
,
1160 Name
=> Indexed_Comp
,
1161 Expression
=> Make_Null
(Loc
)));
1164 if Needs_Finalization
(Ctype
) then
1167 (Obj_Ref
=> New_Copy_Tree
(Indexed_Comp
),
1173 Make_OK_Assignment_Statement
(Loc
,
1174 Name
=> Indexed_Comp
,
1175 Expression
=> New_Copy_Tree
(Expr
));
1177 -- The target of the assignment may not have been initialized,
1178 -- so it is not possible to call Finalize as expected in normal
1179 -- controlled assignments. We must also avoid using the primitive
1180 -- _assign (which depends on a valid target, and may for example
1181 -- perform discriminant checks on it).
1183 -- Both Finalize and usage of _assign are disabled by setting
1184 -- No_Ctrl_Actions on the assignment. The rest of the controlled
1185 -- actions are done manually with the proper finalization list
1186 -- coming from the context.
1188 Set_No_Ctrl_Actions
(A
);
1190 -- If this is an aggregate for an array of arrays, each
1191 -- sub-aggregate will be expanded as well, and even with
1192 -- No_Ctrl_Actions the assignments of inner components will
1193 -- require attachment in their assignments to temporaries. These
1194 -- temporaries must be finalized for each subaggregate, to prevent
1195 -- multiple attachments of the same temporary location to same
1196 -- finalization chain (and consequently circular lists). To ensure
1197 -- that finalization takes place for each subaggregate we wrap the
1198 -- assignment in a block.
1200 if Present
(Comp_Type
)
1201 and then Needs_Finalization
(Comp_Type
)
1202 and then Is_Array_Type
(Comp_Type
)
1203 and then Present
(Expr
)
1206 Make_Block_Statement
(Loc
,
1207 Handled_Statement_Sequence
=>
1208 Make_Handled_Sequence_Of_Statements
(Loc
,
1209 Statements
=> New_List
(A
)));
1214 -- Adjust the tag if tagged (because of possible view
1215 -- conversions), unless compiling for a VM where tags
1218 if Present
(Comp_Type
)
1219 and then Is_Tagged_Type
(Comp_Type
)
1220 and then Tagged_Type_Expansion
1223 Full_Typ
: constant Entity_Id
:= Underlying_Type
(Comp_Type
);
1227 Make_OK_Assignment_Statement
(Loc
,
1229 Make_Selected_Component
(Loc
,
1230 Prefix
=> New_Copy_Tree
(Indexed_Comp
),
1233 (First_Tag_Component
(Full_Typ
), Loc
)),
1236 Unchecked_Convert_To
(RTE
(RE_Tag
),
1238 (Node
(First_Elmt
(Access_Disp_Table
(Full_Typ
))),
1245 -- Adjust and attach the component to the proper final list, which
1246 -- can be the controller of the outer record object or the final
1247 -- list associated with the scope.
1249 -- If the component is itself an array of controlled types, whose
1250 -- value is given by a sub-aggregate, then the attach calls have
1251 -- been generated when individual subcomponent are assigned, and
1252 -- must not be done again to prevent malformed finalization chains
1253 -- (see comments above, concerning the creation of a block to hold
1254 -- inner finalization actions).
1256 if Present
(Comp_Type
)
1257 and then Needs_Finalization
(Comp_Type
)
1258 and then not Is_Limited_Type
(Comp_Type
)
1260 (Is_Array_Type
(Comp_Type
)
1261 and then Is_Controlled
(Component_Type
(Comp_Type
))
1262 and then Nkind
(Expr
) = N_Aggregate
)
1266 (Obj_Ref
=> New_Copy_Tree
(Indexed_Comp
),
1271 return Add_Loop_Actions
(L
);
1278 function Gen_Loop
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1288 -- Index_Base'(L) .. Index_Base'(H)
1290 L_Iteration_Scheme
: Node_Id
;
1291 -- L_J in Index_Base'(L) .. Index_Base'(H)
1294 -- The statements to execute in the loop
1296 S
: constant List_Id
:= New_List
;
1297 -- List of statements
1300 -- Copy of expression tree, used for checking purposes
1303 -- If loop bounds define an empty range return the null statement
1305 if Empty_Range
(L
, H
) then
1306 Append_To
(S
, Make_Null_Statement
(Loc
));
1308 -- Ada 2005 (AI-287): Nothing else need to be done in case of
1309 -- default initialized component.
1315 -- The expression must be type-checked even though no component
1316 -- of the aggregate will have this value. This is done only for
1317 -- actual components of the array, not for subaggregates. Do
1318 -- the check on a copy, because the expression may be shared
1319 -- among several choices, some of which might be non-null.
1321 if Present
(Etype
(N
))
1322 and then Is_Array_Type
(Etype
(N
))
1323 and then No
(Next_Index
(Index
))
1325 Expander_Mode_Save_And_Set
(False);
1326 Tcopy
:= New_Copy_Tree
(Expr
);
1327 Set_Parent
(Tcopy
, N
);
1328 Analyze_And_Resolve
(Tcopy
, Component_Type
(Etype
(N
)));
1329 Expander_Mode_Restore
;
1335 -- If loop bounds are the same then generate an assignment
1337 elsif Equal
(L
, H
) then
1338 return Gen_Assign
(New_Copy_Tree
(L
), Expr
);
1340 -- If H - L <= 2 then generate a sequence of assignments when we are
1341 -- processing the bottom most aggregate and it contains scalar
1344 elsif No
(Next_Index
(Index
))
1345 and then Scalar_Comp
1346 and then Local_Compile_Time_Known_Value
(L
)
1347 and then Local_Compile_Time_Known_Value
(H
)
1348 and then Local_Expr_Value
(H
) - Local_Expr_Value
(L
) <= 2
1351 Append_List_To
(S
, Gen_Assign
(New_Copy_Tree
(L
), Expr
));
1352 Append_List_To
(S
, Gen_Assign
(Add
(1, To
=> L
), Expr
));
1354 if Local_Expr_Value
(H
) - Local_Expr_Value
(L
) = 2 then
1355 Append_List_To
(S
, Gen_Assign
(Add
(2, To
=> L
), Expr
));
1361 -- Otherwise construct the loop, starting with the loop index L_J
1363 L_J
:= Make_Temporary
(Loc
, 'J', L
);
1365 -- Construct "L .. H" in Index_Base. We use a qualified expression
1366 -- for the bound to convert to the index base, but we don't need
1367 -- to do that if we already have the base type at hand.
1369 if Etype
(L
) = Index_Base
then
1373 Make_Qualified_Expression
(Loc
,
1374 Subtype_Mark
=> Index_Base_Name
,
1378 if Etype
(H
) = Index_Base
then
1382 Make_Qualified_Expression
(Loc
,
1383 Subtype_Mark
=> Index_Base_Name
,
1392 -- Construct "for L_J in Index_Base range L .. H"
1394 L_Iteration_Scheme
:=
1395 Make_Iteration_Scheme
1397 Loop_Parameter_Specification
=>
1398 Make_Loop_Parameter_Specification
1400 Defining_Identifier
=> L_J
,
1401 Discrete_Subtype_Definition
=> L_Range
));
1403 -- Construct the statements to execute in the loop body
1405 L_Body
:= Gen_Assign
(New_Occurrence_Of
(L_J
, Loc
), Expr
);
1407 -- Construct the final loop
1410 Make_Implicit_Loop_Statement
1412 Identifier
=> Empty
,
1413 Iteration_Scheme
=> L_Iteration_Scheme
,
1414 Statements
=> L_Body
));
1416 -- A small optimization: if the aggregate is initialized with a box
1417 -- and the component type has no initialization procedure, remove the
1418 -- useless empty loop.
1420 if Nkind
(First
(S
)) = N_Loop_Statement
1421 and then Is_Empty_List
(Statements
(First
(S
)))
1423 return New_List
(Make_Null_Statement
(Loc
));
1433 -- The code built is
1435 -- W_J : Index_Base := L;
1436 -- while W_J < H loop
1437 -- W_J := Index_Base'Succ (W);
1441 function Gen_While
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1445 -- W_J : Base_Type := L;
1447 W_Iteration_Scheme
: Node_Id
;
1450 W_Index_Succ
: Node_Id
;
1451 -- Index_Base'Succ (J)
1453 W_Increment
: Node_Id
;
1454 -- W_J := Index_Base'Succ (W)
1456 W_Body
: constant List_Id
:= New_List
;
1457 -- The statements to execute in the loop
1459 S
: constant List_Id
:= New_List
;
1460 -- list of statement
1463 -- If loop bounds define an empty range or are equal return null
1465 if Empty_Range
(L
, H
) or else Equal
(L
, H
) then
1466 Append_To
(S
, Make_Null_Statement
(Loc
));
1470 -- Build the decl of W_J
1472 W_J
:= Make_Temporary
(Loc
, 'J', L
);
1474 Make_Object_Declaration
1476 Defining_Identifier
=> W_J
,
1477 Object_Definition
=> Index_Base_Name
,
1480 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1481 -- that in this particular case L is a fresh Expr generated by
1482 -- Add which we are the only ones to use.
1484 Append_To
(S
, W_Decl
);
1486 -- Construct " while W_J < H"
1488 W_Iteration_Scheme
:=
1489 Make_Iteration_Scheme
1491 Condition
=> Make_Op_Lt
1493 Left_Opnd
=> New_Occurrence_Of
(W_J
, Loc
),
1494 Right_Opnd
=> New_Copy_Tree
(H
)));
1496 -- Construct the statements to execute in the loop body
1499 Make_Attribute_Reference
1501 Prefix
=> Index_Base_Name
,
1502 Attribute_Name
=> Name_Succ
,
1503 Expressions
=> New_List
(New_Occurrence_Of
(W_J
, Loc
)));
1506 Make_OK_Assignment_Statement
1508 Name
=> New_Occurrence_Of
(W_J
, Loc
),
1509 Expression
=> W_Index_Succ
);
1511 Append_To
(W_Body
, W_Increment
);
1512 Append_List_To
(W_Body
,
1513 Gen_Assign
(New_Occurrence_Of
(W_J
, Loc
), Expr
));
1515 -- Construct the final loop
1518 Make_Implicit_Loop_Statement
1520 Identifier
=> Empty
,
1521 Iteration_Scheme
=> W_Iteration_Scheme
,
1522 Statements
=> W_Body
));
1527 ---------------------
1528 -- Index_Base_Name --
1529 ---------------------
1531 function Index_Base_Name
return Node_Id
is
1533 return New_Occurrence_Of
(Index_Base
, Sloc
(N
));
1534 end Index_Base_Name
;
1536 ------------------------------------
1537 -- Local_Compile_Time_Known_Value --
1538 ------------------------------------
1540 function Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean is
1542 return Compile_Time_Known_Value
(E
)
1544 (Nkind
(E
) = N_Attribute_Reference
1545 and then Attribute_Name
(E
) = Name_Val
1546 and then Compile_Time_Known_Value
(First
(Expressions
(E
))));
1547 end Local_Compile_Time_Known_Value
;
1549 ----------------------
1550 -- Local_Expr_Value --
1551 ----------------------
1553 function Local_Expr_Value
(E
: Node_Id
) return Uint
is
1555 if Compile_Time_Known_Value
(E
) then
1556 return Expr_Value
(E
);
1558 return Expr_Value
(First
(Expressions
(E
)));
1560 end Local_Expr_Value
;
1562 -- Build_Array_Aggr_Code Variables
1569 Others_Expr
: Node_Id
:= Empty
;
1570 Others_Box_Present
: Boolean := False;
1572 Aggr_L
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(N
));
1573 Aggr_H
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(N
));
1574 -- The aggregate bounds of this specific sub-aggregate. Note that if
1575 -- the code generated by Build_Array_Aggr_Code is executed then these
1576 -- bounds are OK. Otherwise a Constraint_Error would have been raised.
1578 Aggr_Low
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_L
);
1579 Aggr_High
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_H
);
1580 -- After Duplicate_Subexpr these are side-effect free
1585 Nb_Choices
: Nat
:= 0;
1586 Table
: Case_Table_Type
(1 .. Number_Of_Choices
(N
));
1587 -- Used to sort all the different choice values
1590 -- Number of elements in the positional aggregate
1592 New_Code
: constant List_Id
:= New_List
;
1594 -- Start of processing for Build_Array_Aggr_Code
1597 -- First before we start, a special case. if we have a bit packed
1598 -- array represented as a modular type, then clear the value to
1599 -- zero first, to ensure that unused bits are properly cleared.
1604 and then Is_Bit_Packed_Array
(Typ
)
1605 and then Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
))
1607 Append_To
(New_Code
,
1608 Make_Assignment_Statement
(Loc
,
1609 Name
=> New_Copy_Tree
(Into
),
1611 Unchecked_Convert_To
(Typ
,
1612 Make_Integer_Literal
(Loc
, Uint_0
))));
1615 -- If the component type contains tasks, we need to build a Master
1616 -- entity in the current scope, because it will be needed if build-
1617 -- in-place functions are called in the expanded code.
1619 if Nkind
(Parent
(N
)) = N_Object_Declaration
and then Has_Task
(Typ
) then
1620 Build_Master_Entity
(Defining_Identifier
(Parent
(N
)));
1623 -- STEP 1: Process component associations
1625 -- For those associations that may generate a loop, initialize
1626 -- Loop_Actions to collect inserted actions that may be crated.
1628 -- Skip this if no component associations
1630 if No
(Expressions
(N
)) then
1632 -- STEP 1 (a): Sort the discrete choices
1634 Assoc
:= First
(Component_Associations
(N
));
1635 while Present
(Assoc
) loop
1636 Choice
:= First
(Choices
(Assoc
));
1637 while Present
(Choice
) loop
1638 if Nkind
(Choice
) = N_Others_Choice
then
1639 Set_Loop_Actions
(Assoc
, New_List
);
1641 if Box_Present
(Assoc
) then
1642 Others_Box_Present
:= True;
1644 Others_Expr
:= Expression
(Assoc
);
1649 Get_Index_Bounds
(Choice
, Low
, High
);
1652 Set_Loop_Actions
(Assoc
, New_List
);
1655 Nb_Choices
:= Nb_Choices
+ 1;
1656 if Box_Present
(Assoc
) then
1657 Table
(Nb_Choices
) := (Choice_Lo
=> Low
,
1659 Choice_Node
=> Empty
);
1661 Table
(Nb_Choices
) := (Choice_Lo
=> Low
,
1663 Choice_Node
=> Expression
(Assoc
));
1671 -- If there is more than one set of choices these must be static
1672 -- and we can therefore sort them. Remember that Nb_Choices does not
1673 -- account for an others choice.
1675 if Nb_Choices
> 1 then
1676 Sort_Case_Table
(Table
);
1679 -- STEP 1 (b): take care of the whole set of discrete choices
1681 for J
in 1 .. Nb_Choices
loop
1682 Low
:= Table
(J
).Choice_Lo
;
1683 High
:= Table
(J
).Choice_Hi
;
1684 Expr
:= Table
(J
).Choice_Node
;
1685 Append_List
(Gen_Loop
(Low
, High
, Expr
), To
=> New_Code
);
1688 -- STEP 1 (c): generate the remaining loops to cover others choice
1689 -- We don't need to generate loops over empty gaps, but if there is
1690 -- a single empty range we must analyze the expression for semantics
1692 if Present
(Others_Expr
) or else Others_Box_Present
then
1694 First
: Boolean := True;
1697 for J
in 0 .. Nb_Choices
loop
1701 Low
:= Add
(1, To
=> Table
(J
).Choice_Hi
);
1704 if J
= Nb_Choices
then
1707 High
:= Add
(-1, To
=> Table
(J
+ 1).Choice_Lo
);
1710 -- If this is an expansion within an init proc, make
1711 -- sure that discriminant references are replaced by
1712 -- the corresponding discriminal.
1714 if Inside_Init_Proc
then
1715 if Is_Entity_Name
(Low
)
1716 and then Ekind
(Entity
(Low
)) = E_Discriminant
1718 Set_Entity
(Low
, Discriminal
(Entity
(Low
)));
1721 if Is_Entity_Name
(High
)
1722 and then Ekind
(Entity
(High
)) = E_Discriminant
1724 Set_Entity
(High
, Discriminal
(Entity
(High
)));
1729 or else not Empty_Range
(Low
, High
)
1733 (Gen_Loop
(Low
, High
, Others_Expr
), To
=> New_Code
);
1739 -- STEP 2: Process positional components
1742 -- STEP 2 (a): Generate the assignments for each positional element
1743 -- Note that here we have to use Aggr_L rather than Aggr_Low because
1744 -- Aggr_L is analyzed and Add wants an analyzed expression.
1746 Expr
:= First
(Expressions
(N
));
1748 while Present
(Expr
) loop
1749 Nb_Elements
:= Nb_Elements
+ 1;
1750 Append_List
(Gen_Assign
(Add
(Nb_Elements
, To
=> Aggr_L
), Expr
),
1755 -- STEP 2 (b): Generate final loop if an others choice is present
1756 -- Here Nb_Elements gives the offset of the last positional element.
1758 if Present
(Component_Associations
(N
)) then
1759 Assoc
:= Last
(Component_Associations
(N
));
1761 -- Ada 2005 (AI-287)
1763 if Box_Present
(Assoc
) then
1764 Append_List
(Gen_While
(Add
(Nb_Elements
, To
=> Aggr_L
),
1769 Expr
:= Expression
(Assoc
);
1771 Append_List
(Gen_While
(Add
(Nb_Elements
, To
=> Aggr_L
),
1780 end Build_Array_Aggr_Code
;
1782 ----------------------------
1783 -- Build_Record_Aggr_Code --
1784 ----------------------------
1786 function Build_Record_Aggr_Code
1789 Lhs
: Node_Id
) return List_Id
1791 Loc
: constant Source_Ptr
:= Sloc
(N
);
1792 L
: constant List_Id
:= New_List
;
1793 N_Typ
: constant Entity_Id
:= Etype
(N
);
1799 Comp_Type
: Entity_Id
;
1800 Selector
: Entity_Id
;
1801 Comp_Expr
: Node_Id
;
1804 -- If this is an internal aggregate, the External_Final_List is an
1805 -- expression for the controller record of the enclosing type.
1807 -- If the current aggregate has several controlled components, this
1808 -- expression will appear in several calls to attach to the finali-
1809 -- zation list, and it must not be shared.
1811 Ancestor_Is_Expression
: Boolean := False;
1812 Ancestor_Is_Subtype_Mark
: Boolean := False;
1814 Init_Typ
: Entity_Id
:= Empty
;
1816 Finalization_Done
: Boolean := False;
1817 -- True if Generate_Finalization_Actions has already been called; calls
1818 -- after the first do nothing.
1820 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
;
1821 -- Returns the value that the given discriminant of an ancestor type
1822 -- should receive (in the absence of a conflict with the value provided
1823 -- by an ancestor part of an extension aggregate).
1825 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
);
1826 -- Check that each of the discriminant values defined by the ancestor
1827 -- part of an extension aggregate match the corresponding values
1828 -- provided by either an association of the aggregate or by the
1829 -- constraint imposed by a parent type (RM95-4.3.2(8)).
1831 function Compatible_Int_Bounds
1832 (Agg_Bounds
: Node_Id
;
1833 Typ_Bounds
: Node_Id
) return Boolean;
1834 -- Return true if Agg_Bounds are equal or within Typ_Bounds. It is
1835 -- assumed that both bounds are integer ranges.
1837 procedure Generate_Finalization_Actions
;
1838 -- Deal with the various controlled type data structure initializations
1839 -- (but only if it hasn't been done already).
1841 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
;
1842 -- Returns the first discriminant association in the constraint
1843 -- associated with T, if any, otherwise returns Empty.
1845 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
);
1846 -- If Typ is derived, and constrains discriminants of the parent type,
1847 -- these discriminants are not components of the aggregate, and must be
1848 -- initialized. The assignments are appended to List. The same is done
1849 -- if Typ derives fron an already constrained subtype of a discriminated
1852 function Get_Explicit_Discriminant_Value
(D
: Entity_Id
) return Node_Id
;
1853 -- If the ancestor part is an unconstrained type and further ancestors
1854 -- do not provide discriminants for it, check aggregate components for
1855 -- values of the discriminants.
1857 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean;
1858 -- Check whether Bounds is a range node and its lower and higher bounds
1859 -- are integers literals.
1861 ---------------------------------
1862 -- Ancestor_Discriminant_Value --
1863 ---------------------------------
1865 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
is
1867 Assoc_Elmt
: Elmt_Id
;
1868 Aggr_Comp
: Entity_Id
;
1869 Corresp_Disc
: Entity_Id
;
1870 Current_Typ
: Entity_Id
:= Base_Type
(Typ
);
1871 Parent_Typ
: Entity_Id
;
1872 Parent_Disc
: Entity_Id
;
1873 Save_Assoc
: Node_Id
:= Empty
;
1876 -- First check any discriminant associations to see if any of them
1877 -- provide a value for the discriminant.
1879 if Present
(Discriminant_Specifications
(Parent
(Current_Typ
))) then
1880 Assoc
:= First
(Component_Associations
(N
));
1881 while Present
(Assoc
) loop
1882 Aggr_Comp
:= Entity
(First
(Choices
(Assoc
)));
1884 if Ekind
(Aggr_Comp
) = E_Discriminant
then
1885 Save_Assoc
:= Expression
(Assoc
);
1887 Corresp_Disc
:= Corresponding_Discriminant
(Aggr_Comp
);
1888 while Present
(Corresp_Disc
) loop
1890 -- If found a corresponding discriminant then return the
1891 -- value given in the aggregate. (Note: this is not
1892 -- correct in the presence of side effects. ???)
1894 if Disc
= Corresp_Disc
then
1895 return Duplicate_Subexpr
(Expression
(Assoc
));
1899 Corresponding_Discriminant
(Corresp_Disc
);
1907 -- No match found in aggregate, so chain up parent types to find
1908 -- a constraint that defines the value of the discriminant.
1910 Parent_Typ
:= Etype
(Current_Typ
);
1911 while Current_Typ
/= Parent_Typ
loop
1912 if Has_Discriminants
(Parent_Typ
)
1913 and then not Has_Unknown_Discriminants
(Parent_Typ
)
1915 Parent_Disc
:= First_Discriminant
(Parent_Typ
);
1917 -- We either get the association from the subtype indication
1918 -- of the type definition itself, or from the discriminant
1919 -- constraint associated with the type entity (which is
1920 -- preferable, but it's not always present ???)
1922 if Is_Empty_Elmt_List
(
1923 Discriminant_Constraint
(Current_Typ
))
1925 Assoc
:= Get_Constraint_Association
(Current_Typ
);
1926 Assoc_Elmt
:= No_Elmt
;
1929 First_Elmt
(Discriminant_Constraint
(Current_Typ
));
1930 Assoc
:= Node
(Assoc_Elmt
);
1933 -- Traverse the discriminants of the parent type looking
1934 -- for one that corresponds.
1936 while Present
(Parent_Disc
) and then Present
(Assoc
) loop
1937 Corresp_Disc
:= Parent_Disc
;
1938 while Present
(Corresp_Disc
)
1939 and then Disc
/= Corresp_Disc
1942 Corresponding_Discriminant
(Corresp_Disc
);
1945 if Disc
= Corresp_Disc
then
1946 if Nkind
(Assoc
) = N_Discriminant_Association
then
1947 Assoc
:= Expression
(Assoc
);
1950 -- If the located association directly denotes
1951 -- a discriminant, then use the value of a saved
1952 -- association of the aggregate. This is an approach
1953 -- used to handle certain cases involving multiple
1954 -- discriminants mapped to a single discriminant of
1955 -- a descendant. It's not clear how to locate the
1956 -- appropriate discriminant value for such cases. ???
1958 if Is_Entity_Name
(Assoc
)
1959 and then Ekind
(Entity
(Assoc
)) = E_Discriminant
1961 Assoc
:= Save_Assoc
;
1964 return Duplicate_Subexpr
(Assoc
);
1967 Next_Discriminant
(Parent_Disc
);
1969 if No
(Assoc_Elmt
) then
1972 Next_Elmt
(Assoc_Elmt
);
1973 if Present
(Assoc_Elmt
) then
1974 Assoc
:= Node
(Assoc_Elmt
);
1982 Current_Typ
:= Parent_Typ
;
1983 Parent_Typ
:= Etype
(Current_Typ
);
1986 -- In some cases there's no ancestor value to locate (such as
1987 -- when an ancestor part given by an expression defines the
1988 -- discriminant value).
1991 end Ancestor_Discriminant_Value
;
1993 ----------------------------------
1994 -- Check_Ancestor_Discriminants --
1995 ----------------------------------
1997 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
) is
1999 Disc_Value
: Node_Id
;
2003 Discr
:= First_Discriminant
(Base_Type
(Anc_Typ
));
2004 while Present
(Discr
) loop
2005 Disc_Value
:= Ancestor_Discriminant_Value
(Discr
);
2007 if Present
(Disc_Value
) then
2008 Cond
:= Make_Op_Ne
(Loc
,
2010 Make_Selected_Component
(Loc
,
2011 Prefix
=> New_Copy_Tree
(Target
),
2012 Selector_Name
=> New_Occurrence_Of
(Discr
, Loc
)),
2013 Right_Opnd
=> Disc_Value
);
2016 Make_Raise_Constraint_Error
(Loc
,
2018 Reason
=> CE_Discriminant_Check_Failed
));
2021 Next_Discriminant
(Discr
);
2023 end Check_Ancestor_Discriminants
;
2025 ---------------------------
2026 -- Compatible_Int_Bounds --
2027 ---------------------------
2029 function Compatible_Int_Bounds
2030 (Agg_Bounds
: Node_Id
;
2031 Typ_Bounds
: Node_Id
) return Boolean
2033 Agg_Lo
: constant Uint
:= Intval
(Low_Bound
(Agg_Bounds
));
2034 Agg_Hi
: constant Uint
:= Intval
(High_Bound
(Agg_Bounds
));
2035 Typ_Lo
: constant Uint
:= Intval
(Low_Bound
(Typ_Bounds
));
2036 Typ_Hi
: constant Uint
:= Intval
(High_Bound
(Typ_Bounds
));
2038 return Typ_Lo
<= Agg_Lo
and then Agg_Hi
<= Typ_Hi
;
2039 end Compatible_Int_Bounds
;
2041 --------------------------------
2042 -- Get_Constraint_Association --
2043 --------------------------------
2045 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
is
2052 -- Handle private types in instances
2055 and then Is_Private_Type
(Typ
)
2056 and then Present
(Full_View
(Typ
))
2058 Typ
:= Full_View
(Typ
);
2061 Indic
:= Subtype_Indication
(Type_Definition
(Parent
(Typ
)));
2063 -- ??? Also need to cover case of a type mark denoting a subtype
2066 if Nkind
(Indic
) = N_Subtype_Indication
2067 and then Present
(Constraint
(Indic
))
2069 return First
(Constraints
(Constraint
(Indic
)));
2073 end Get_Constraint_Association
;
2075 -------------------------------------
2076 -- Get_Explicit_Discriminant_Value --
2077 -------------------------------------
2079 function Get_Explicit_Discriminant_Value
2080 (D
: Entity_Id
) return Node_Id
2087 -- The aggregate has been normalized and all associations have a
2090 Assoc
:= First
(Component_Associations
(N
));
2091 while Present
(Assoc
) loop
2092 Choice
:= First
(Choices
(Assoc
));
2094 if Chars
(Choice
) = Chars
(D
) then
2095 Val
:= Expression
(Assoc
);
2104 end Get_Explicit_Discriminant_Value
;
2106 -------------------------------
2107 -- Init_Hidden_Discriminants --
2108 -------------------------------
2110 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
) is
2112 Parent_Type
: Entity_Id
;
2114 Discr_Val
: Elmt_Id
;
2117 -- The constraints on the hidden discriminants, if present, are kept
2118 -- in the Stored_Constraint list of the type itself, or in that of
2121 Btype
:= Base_Type
(Typ
);
2122 while Is_Derived_Type
(Btype
)
2123 and then (Present
(Stored_Constraint
(Btype
))
2125 Present
(Stored_Constraint
(Typ
)))
2127 Parent_Type
:= Etype
(Btype
);
2129 if not Has_Discriminants
(Parent_Type
) then
2133 Disc
:= First_Discriminant
(Parent_Type
);
2135 -- We know that one of the stored-constraint lists is present
2137 if Present
(Stored_Constraint
(Btype
)) then
2138 Discr_Val
:= First_Elmt
(Stored_Constraint
(Btype
));
2140 -- For private extension, stored constraint may be on full view
2142 elsif Is_Private_Type
(Btype
)
2143 and then Present
(Full_View
(Btype
))
2144 and then Present
(Stored_Constraint
(Full_View
(Btype
)))
2146 Discr_Val
:= First_Elmt
(Stored_Constraint
(Full_View
(Btype
)));
2149 Discr_Val
:= First_Elmt
(Stored_Constraint
(Typ
));
2152 while Present
(Discr_Val
) loop
2154 -- Only those discriminants of the parent that are not
2155 -- renamed by discriminants of the derived type need to
2156 -- be added explicitly.
2158 if not Is_Entity_Name
(Node
(Discr_Val
))
2159 or else Ekind
(Entity
(Node
(Discr_Val
))) /= E_Discriminant
2162 Make_Selected_Component
(Loc
,
2163 Prefix
=> New_Copy_Tree
(Target
),
2164 Selector_Name
=> New_Occurrence_Of
(Disc
, Loc
));
2167 Make_OK_Assignment_Statement
(Loc
,
2169 Expression
=> New_Copy_Tree
(Node
(Discr_Val
)));
2171 Set_No_Ctrl_Actions
(Instr
);
2172 Append_To
(List
, Instr
);
2175 Next_Discriminant
(Disc
);
2176 Next_Elmt
(Discr_Val
);
2179 Btype
:= Base_Type
(Parent_Type
);
2181 end Init_Hidden_Discriminants
;
2183 -------------------------
2184 -- Is_Int_Range_Bounds --
2185 -------------------------
2187 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean is
2189 return Nkind
(Bounds
) = N_Range
2190 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
2191 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
;
2192 end Is_Int_Range_Bounds
;
2194 -----------------------------------
2195 -- Generate_Finalization_Actions --
2196 -----------------------------------
2198 procedure Generate_Finalization_Actions
is
2200 -- Do the work only the first time this is called
2202 if Finalization_Done
then
2206 Finalization_Done
:= True;
2208 -- Determine the external finalization list. It is either the
2209 -- finalization list of the outer-scope or the one coming from an
2210 -- outer aggregate. When the target is not a temporary, the proper
2211 -- scope is the scope of the target rather than the potentially
2212 -- transient current scope.
2214 if Is_Controlled
(Typ
) and then Ancestor_Is_Subtype_Mark
then
2215 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2216 Set_Assignment_OK
(Ref
);
2219 Make_Procedure_Call_Statement
(Loc
,
2222 (Find_Prim_Op
(Init_Typ
, Name_Initialize
), Loc
),
2223 Parameter_Associations
=> New_List
(New_Copy_Tree
(Ref
))));
2225 end Generate_Finalization_Actions
;
2227 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
;
2228 -- If default expression of a component mentions a discriminant of the
2229 -- type, it must be rewritten as the discriminant of the target object.
2231 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
;
2232 -- If the aggregate contains a self-reference, traverse each expression
2233 -- to replace a possible self-reference with a reference to the proper
2234 -- component of the target of the assignment.
2236 --------------------------
2237 -- Rewrite_Discriminant --
2238 --------------------------
2240 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
is
2242 if Is_Entity_Name
(Expr
)
2243 and then Present
(Entity
(Expr
))
2244 and then Ekind
(Entity
(Expr
)) = E_In_Parameter
2245 and then Present
(Discriminal_Link
(Entity
(Expr
)))
2246 and then Scope
(Discriminal_Link
(Entity
(Expr
))) =
2247 Base_Type
(Etype
(N
))
2250 Make_Selected_Component
(Loc
,
2251 Prefix
=> New_Copy_Tree
(Lhs
),
2252 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Expr
))));
2256 end Rewrite_Discriminant
;
2262 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
is
2264 -- Note regarding the Root_Type test below: Aggregate components for
2265 -- self-referential types include attribute references to the current
2266 -- instance, of the form: Typ'access, etc.. These references are
2267 -- rewritten as references to the target of the aggregate: the
2268 -- left-hand side of an assignment, the entity in a declaration,
2269 -- or a temporary. Without this test, we would improperly extended
2270 -- this rewriting to attribute references whose prefix was not the
2271 -- type of the aggregate.
2273 if Nkind
(Expr
) = N_Attribute_Reference
2274 and then Is_Entity_Name
(Prefix
(Expr
))
2275 and then Is_Type
(Entity
(Prefix
(Expr
)))
2276 and then Root_Type
(Etype
(N
)) = Root_Type
(Entity
(Prefix
(Expr
)))
2278 if Is_Entity_Name
(Lhs
) then
2279 Rewrite
(Prefix
(Expr
),
2280 New_Occurrence_Of
(Entity
(Lhs
), Loc
));
2282 elsif Nkind
(Lhs
) = N_Selected_Component
then
2284 Make_Attribute_Reference
(Loc
,
2285 Attribute_Name
=> Name_Unrestricted_Access
,
2286 Prefix
=> New_Copy_Tree
(Lhs
)));
2287 Set_Analyzed
(Parent
(Expr
), False);
2291 Make_Attribute_Reference
(Loc
,
2292 Attribute_Name
=> Name_Unrestricted_Access
,
2293 Prefix
=> New_Copy_Tree
(Lhs
)));
2294 Set_Analyzed
(Parent
(Expr
), False);
2301 procedure Replace_Self_Reference
is
2302 new Traverse_Proc
(Replace_Type
);
2304 procedure Replace_Discriminants
is
2305 new Traverse_Proc
(Rewrite_Discriminant
);
2307 -- Start of processing for Build_Record_Aggr_Code
2310 if Has_Self_Reference
(N
) then
2311 Replace_Self_Reference
(N
);
2314 -- If the target of the aggregate is class-wide, we must convert it
2315 -- to the actual type of the aggregate, so that the proper components
2316 -- are visible. We know already that the types are compatible.
2318 if Present
(Etype
(Lhs
))
2319 and then Is_Class_Wide_Type
(Etype
(Lhs
))
2321 Target
:= Unchecked_Convert_To
(Typ
, Lhs
);
2326 -- Deal with the ancestor part of extension aggregates or with the
2327 -- discriminants of the root type.
2329 if Nkind
(N
) = N_Extension_Aggregate
then
2331 Ancestor
: constant Node_Id
:= Ancestor_Part
(N
);
2335 -- If the ancestor part is a subtype mark "T", we generate
2337 -- init-proc (T (tmp)); if T is constrained and
2338 -- init-proc (S (tmp)); where S applies an appropriate
2339 -- constraint if T is unconstrained
2341 if Is_Entity_Name
(Ancestor
)
2342 and then Is_Type
(Entity
(Ancestor
))
2344 Ancestor_Is_Subtype_Mark
:= True;
2346 if Is_Constrained
(Entity
(Ancestor
)) then
2347 Init_Typ
:= Entity
(Ancestor
);
2349 -- For an ancestor part given by an unconstrained type mark,
2350 -- create a subtype constrained by appropriate corresponding
2351 -- discriminant values coming from either associations of the
2352 -- aggregate or a constraint on a parent type. The subtype will
2353 -- be used to generate the correct default value for the
2356 elsif Has_Discriminants
(Entity
(Ancestor
)) then
2358 Anc_Typ
: constant Entity_Id
:= Entity
(Ancestor
);
2359 Anc_Constr
: constant List_Id
:= New_List
;
2360 Discrim
: Entity_Id
;
2361 Disc_Value
: Node_Id
;
2362 New_Indic
: Node_Id
;
2363 Subt_Decl
: Node_Id
;
2366 Discrim
:= First_Discriminant
(Anc_Typ
);
2367 while Present
(Discrim
) loop
2368 Disc_Value
:= Ancestor_Discriminant_Value
(Discrim
);
2370 -- If no usable discriminant in ancestors, check
2371 -- whether aggregate has an explicit value for it.
2373 if No
(Disc_Value
) then
2375 Get_Explicit_Discriminant_Value
(Discrim
);
2378 Append_To
(Anc_Constr
, Disc_Value
);
2379 Next_Discriminant
(Discrim
);
2383 Make_Subtype_Indication
(Loc
,
2384 Subtype_Mark
=> New_Occurrence_Of
(Anc_Typ
, Loc
),
2386 Make_Index_Or_Discriminant_Constraint
(Loc
,
2387 Constraints
=> Anc_Constr
));
2389 Init_Typ
:= Create_Itype
(Ekind
(Anc_Typ
), N
);
2392 Make_Subtype_Declaration
(Loc
,
2393 Defining_Identifier
=> Init_Typ
,
2394 Subtype_Indication
=> New_Indic
);
2396 -- Itypes must be analyzed with checks off Declaration
2397 -- must have a parent for proper handling of subsidiary
2400 Set_Parent
(Subt_Decl
, N
);
2401 Analyze
(Subt_Decl
, Suppress
=> All_Checks
);
2405 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2406 Set_Assignment_OK
(Ref
);
2408 if not Is_Interface
(Init_Typ
) then
2410 Build_Initialization_Call
(Loc
,
2413 In_Init_Proc
=> Within_Init_Proc
,
2414 With_Default_Init
=> Has_Default_Init_Comps
(N
)
2416 Has_Task
(Base_Type
(Init_Typ
))));
2418 if Is_Constrained
(Entity
(Ancestor
))
2419 and then Has_Discriminants
(Entity
(Ancestor
))
2421 Check_Ancestor_Discriminants
(Entity
(Ancestor
));
2425 -- Handle calls to C++ constructors
2427 elsif Is_CPP_Constructor_Call
(Ancestor
) then
2428 Init_Typ
:= Etype
(Ancestor
);
2429 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2430 Set_Assignment_OK
(Ref
);
2433 Build_Initialization_Call
(Loc
,
2436 In_Init_Proc
=> Within_Init_Proc
,
2437 With_Default_Init
=> Has_Default_Init_Comps
(N
),
2438 Constructor_Ref
=> Ancestor
));
2440 -- Ada 2005 (AI-287): If the ancestor part is an aggregate of
2441 -- limited type, a recursive call expands the ancestor. Note that
2442 -- in the limited case, the ancestor part must be either a
2443 -- function call (possibly qualified, or wrapped in an unchecked
2444 -- conversion) or aggregate (definitely qualified).
2446 -- The ancestor part can also be a function call (that may be
2447 -- transformed into an explicit dereference) or a qualification
2450 elsif Is_Limited_Type
(Etype
(Ancestor
))
2451 and then Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
2452 N_Extension_Aggregate
)
2454 Ancestor_Is_Expression
:= True;
2456 -- Set up finalization data for enclosing record, because
2457 -- controlled subcomponents of the ancestor part will be
2460 Generate_Finalization_Actions
;
2463 Build_Record_Aggr_Code
2464 (N
=> Unqualify
(Ancestor
),
2465 Typ
=> Etype
(Unqualify
(Ancestor
)),
2468 -- If the ancestor part is an expression "E", we generate
2472 -- In Ada 2005, this includes the case of a (possibly qualified)
2473 -- limited function call. The assignment will turn into a
2474 -- build-in-place function call (for further details, see
2475 -- Make_Build_In_Place_Call_In_Assignment).
2478 Ancestor_Is_Expression
:= True;
2479 Init_Typ
:= Etype
(Ancestor
);
2481 -- If the ancestor part is an aggregate, force its full
2482 -- expansion, which was delayed.
2484 if Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
2485 N_Extension_Aggregate
)
2487 Set_Analyzed
(Ancestor
, False);
2488 Set_Analyzed
(Expression
(Ancestor
), False);
2491 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2492 Set_Assignment_OK
(Ref
);
2494 -- Make the assignment without usual controlled actions, since
2495 -- we only want to Adjust afterwards, but not to Finalize
2496 -- beforehand. Add manual Adjust when necessary.
2498 Assign
:= New_List
(
2499 Make_OK_Assignment_Statement
(Loc
,
2501 Expression
=> Ancestor
));
2502 Set_No_Ctrl_Actions
(First
(Assign
));
2504 -- Assign the tag now to make sure that the dispatching call in
2505 -- the subsequent deep_adjust works properly (unless VM_Target,
2506 -- where tags are implicit).
2508 if Tagged_Type_Expansion
then
2510 Make_OK_Assignment_Statement
(Loc
,
2512 Make_Selected_Component
(Loc
,
2513 Prefix
=> New_Copy_Tree
(Target
),
2516 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
2519 Unchecked_Convert_To
(RTE
(RE_Tag
),
2522 (Access_Disp_Table
(Base_Type
(Typ
)))),
2525 Set_Assignment_OK
(Name
(Instr
));
2526 Append_To
(Assign
, Instr
);
2528 -- Ada 2005 (AI-251): If tagged type has progenitors we must
2529 -- also initialize tags of the secondary dispatch tables.
2531 if Has_Interfaces
(Base_Type
(Typ
)) then
2533 (Typ
=> Base_Type
(Typ
),
2535 Stmts_List
=> Assign
);
2539 -- Call Adjust manually
2541 if Needs_Finalization
(Etype
(Ancestor
))
2542 and then not Is_Limited_Type
(Etype
(Ancestor
))
2546 (Obj_Ref
=> New_Copy_Tree
(Ref
),
2547 Typ
=> Etype
(Ancestor
)));
2551 Make_Unsuppress_Block
(Loc
, Name_Discriminant_Check
, Assign
));
2553 if Has_Discriminants
(Init_Typ
) then
2554 Check_Ancestor_Discriminants
(Init_Typ
);
2559 -- Generate assignments of hidden discriminants. If the base type is
2560 -- an unchecked union, the discriminants are unknown to the back-end
2561 -- and absent from a value of the type, so assignments for them are
2564 if Has_Discriminants
(Typ
)
2565 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
2567 Init_Hidden_Discriminants
(Typ
, L
);
2570 -- Normal case (not an extension aggregate)
2573 -- Generate the discriminant expressions, component by component.
2574 -- If the base type is an unchecked union, the discriminants are
2575 -- unknown to the back-end and absent from a value of the type, so
2576 -- assignments for them are not emitted.
2578 if Has_Discriminants
(Typ
)
2579 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
2581 Init_Hidden_Discriminants
(Typ
, L
);
2583 -- Generate discriminant init values for the visible discriminants
2586 Discriminant
: Entity_Id
;
2587 Discriminant_Value
: Node_Id
;
2590 Discriminant
:= First_Stored_Discriminant
(Typ
);
2591 while Present
(Discriminant
) loop
2593 Make_Selected_Component
(Loc
,
2594 Prefix
=> New_Copy_Tree
(Target
),
2595 Selector_Name
=> New_Occurrence_Of
(Discriminant
, Loc
));
2597 Discriminant_Value
:=
2598 Get_Discriminant_Value
(
2601 Discriminant_Constraint
(N_Typ
));
2604 Make_OK_Assignment_Statement
(Loc
,
2606 Expression
=> New_Copy_Tree
(Discriminant_Value
));
2608 Set_No_Ctrl_Actions
(Instr
);
2609 Append_To
(L
, Instr
);
2611 Next_Stored_Discriminant
(Discriminant
);
2617 -- For CPP types we generate an implicit call to the C++ default
2618 -- constructor to ensure the proper initialization of the _Tag
2621 if Is_CPP_Class
(Root_Type
(Typ
)) and then CPP_Num_Prims
(Typ
) > 0 then
2622 Invoke_Constructor
: declare
2623 CPP_Parent
: constant Entity_Id
:= Enclosing_CPP_Parent
(Typ
);
2625 procedure Invoke_IC_Proc
(T
: Entity_Id
);
2626 -- Recursive routine used to climb to parents. Required because
2627 -- parents must be initialized before descendants to ensure
2628 -- propagation of inherited C++ slots.
2630 --------------------
2631 -- Invoke_IC_Proc --
2632 --------------------
2634 procedure Invoke_IC_Proc
(T
: Entity_Id
) is
2636 -- Avoid generating extra calls. Initialization required
2637 -- only for types defined from the level of derivation of
2638 -- type of the constructor and the type of the aggregate.
2640 if T
= CPP_Parent
then
2644 Invoke_IC_Proc
(Etype
(T
));
2646 -- Generate call to the IC routine
2648 if Present
(CPP_Init_Proc
(T
)) then
2650 Make_Procedure_Call_Statement
(Loc
,
2651 New_Occurrence_Of
(CPP_Init_Proc
(T
), Loc
)));
2655 -- Start of processing for Invoke_Constructor
2658 -- Implicit invocation of the C++ constructor
2660 if Nkind
(N
) = N_Aggregate
then
2662 Make_Procedure_Call_Statement
(Loc
,
2664 New_Occurrence_Of
(Base_Init_Proc
(CPP_Parent
), Loc
),
2665 Parameter_Associations
=> New_List
(
2666 Unchecked_Convert_To
(CPP_Parent
,
2667 New_Copy_Tree
(Lhs
)))));
2670 Invoke_IC_Proc
(Typ
);
2671 end Invoke_Constructor
;
2674 -- Generate the assignments, component by component
2676 -- tmp.comp1 := Expr1_From_Aggr;
2677 -- tmp.comp2 := Expr2_From_Aggr;
2680 Comp
:= First
(Component_Associations
(N
));
2681 while Present
(Comp
) loop
2682 Selector
:= Entity
(First
(Choices
(Comp
)));
2686 if Is_CPP_Constructor_Call
(Expression
(Comp
)) then
2688 Build_Initialization_Call
(Loc
,
2690 Make_Selected_Component
(Loc
,
2691 Prefix
=> New_Copy_Tree
(Target
),
2692 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
)),
2693 Typ
=> Etype
(Selector
),
2695 With_Default_Init
=> True,
2696 Constructor_Ref
=> Expression
(Comp
)));
2698 -- Ada 2005 (AI-287): For each default-initialized component generate
2699 -- a call to the corresponding IP subprogram if available.
2701 elsif Box_Present
(Comp
)
2702 and then Has_Non_Null_Base_Init_Proc
(Etype
(Selector
))
2704 if Ekind
(Selector
) /= E_Discriminant
then
2705 Generate_Finalization_Actions
;
2708 -- Ada 2005 (AI-287): If the component type has tasks then
2709 -- generate the activation chain and master entities (except
2710 -- in case of an allocator because in that case these entities
2711 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
2714 Ctype
: constant Entity_Id
:= Etype
(Selector
);
2715 Inside_Allocator
: Boolean := False;
2716 P
: Node_Id
:= Parent
(N
);
2719 if Is_Task_Type
(Ctype
) or else Has_Task
(Ctype
) then
2720 while Present
(P
) loop
2721 if Nkind
(P
) = N_Allocator
then
2722 Inside_Allocator
:= True;
2729 if not Inside_Init_Proc
and not Inside_Allocator
then
2730 Build_Activation_Chain_Entity
(N
);
2736 Build_Initialization_Call
(Loc
,
2737 Id_Ref
=> Make_Selected_Component
(Loc
,
2738 Prefix
=> New_Copy_Tree
(Target
),
2740 New_Occurrence_Of
(Selector
, Loc
)),
2741 Typ
=> Etype
(Selector
),
2743 With_Default_Init
=> True));
2745 -- Prepare for component assignment
2747 elsif Ekind
(Selector
) /= E_Discriminant
2748 or else Nkind
(N
) = N_Extension_Aggregate
2750 -- All the discriminants have now been assigned
2752 -- This is now a good moment to initialize and attach all the
2753 -- controllers. Their position may depend on the discriminants.
2755 if Ekind
(Selector
) /= E_Discriminant
then
2756 Generate_Finalization_Actions
;
2759 Comp_Type
:= Underlying_Type
(Etype
(Selector
));
2761 Make_Selected_Component
(Loc
,
2762 Prefix
=> New_Copy_Tree
(Target
),
2763 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
));
2765 if Nkind
(Expression
(Comp
)) = N_Qualified_Expression
then
2766 Expr_Q
:= Expression
(Expression
(Comp
));
2768 Expr_Q
:= Expression
(Comp
);
2771 -- Now either create the assignment or generate the code for the
2772 -- inner aggregate top-down.
2774 if Is_Delayed_Aggregate
(Expr_Q
) then
2776 -- We have the following case of aggregate nesting inside
2777 -- an object declaration:
2779 -- type Arr_Typ is array (Integer range <>) of ...;
2781 -- type Rec_Typ (...) is record
2782 -- Obj_Arr_Typ : Arr_Typ (A .. B);
2785 -- Obj_Rec_Typ : Rec_Typ := (...,
2786 -- Obj_Arr_Typ => (X => (...), Y => (...)));
2788 -- The length of the ranges of the aggregate and Obj_Add_Typ
2789 -- are equal (B - A = Y - X), but they do not coincide (X /=
2790 -- A and B /= Y). This case requires array sliding which is
2791 -- performed in the following manner:
2793 -- subtype Arr_Sub is Arr_Typ (X .. Y);
2795 -- Temp (X) := (...);
2797 -- Temp (Y) := (...);
2798 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
2800 if Ekind
(Comp_Type
) = E_Array_Subtype
2801 and then Is_Int_Range_Bounds
(Aggregate_Bounds
(Expr_Q
))
2802 and then Is_Int_Range_Bounds
(First_Index
(Comp_Type
))
2804 Compatible_Int_Bounds
2805 (Agg_Bounds
=> Aggregate_Bounds
(Expr_Q
),
2806 Typ_Bounds
=> First_Index
(Comp_Type
))
2808 -- Create the array subtype with bounds equal to those of
2809 -- the corresponding aggregate.
2812 SubE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
2814 SubD
: constant Node_Id
:=
2815 Make_Subtype_Declaration
(Loc
,
2816 Defining_Identifier
=> SubE
,
2817 Subtype_Indication
=>
2818 Make_Subtype_Indication
(Loc
,
2820 New_Occurrence_Of
(Etype
(Comp_Type
), Loc
),
2822 Make_Index_Or_Discriminant_Constraint
2824 Constraints
=> New_List
(
2826 (Aggregate_Bounds
(Expr_Q
))))));
2828 -- Create a temporary array of the above subtype which
2829 -- will be used to capture the aggregate assignments.
2831 TmpE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A', N
);
2833 TmpD
: constant Node_Id
:=
2834 Make_Object_Declaration
(Loc
,
2835 Defining_Identifier
=> TmpE
,
2836 Object_Definition
=> New_Occurrence_Of
(SubE
, Loc
));
2839 Set_No_Initialization
(TmpD
);
2840 Append_To
(L
, SubD
);
2841 Append_To
(L
, TmpD
);
2843 -- Expand aggregate into assignments to the temp array
2846 Late_Expansion
(Expr_Q
, Comp_Type
,
2847 New_Occurrence_Of
(TmpE
, Loc
)));
2852 Make_Assignment_Statement
(Loc
,
2853 Name
=> New_Copy_Tree
(Comp_Expr
),
2854 Expression
=> New_Occurrence_Of
(TmpE
, Loc
)));
2857 -- Normal case (sliding not required)
2861 Late_Expansion
(Expr_Q
, Comp_Type
, Comp_Expr
));
2864 -- Expr_Q is not delayed aggregate
2867 if Has_Discriminants
(Typ
) then
2868 Replace_Discriminants
(Expr_Q
);
2870 -- If the component is an array type that depends on
2871 -- discriminants, and the expression is a single Others
2872 -- clause, create an explicit subtype for it because the
2873 -- backend has troubles recovering the actual bounds.
2875 if Nkind
(Expr_Q
) = N_Aggregate
2876 and then Is_Array_Type
(Comp_Type
)
2877 and then Present
(Component_Associations
(Expr_Q
))
2880 Assoc
: constant Node_Id
:=
2881 First
(Component_Associations
(Expr_Q
));
2885 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
2888 Build_Actual_Subtype_Of_Component
2889 (Comp_Type
, Comp_Expr
);
2891 -- If the component type does not in fact depend on
2892 -- discriminants, the subtype declaration is empty.
2894 if Present
(Decl
) then
2895 Append_To
(L
, Decl
);
2896 Set_Etype
(Comp_Expr
, Defining_Entity
(Decl
));
2904 Make_OK_Assignment_Statement
(Loc
,
2906 Expression
=> Expr_Q
);
2908 Set_No_Ctrl_Actions
(Instr
);
2909 Append_To
(L
, Instr
);
2911 -- Adjust the tag if tagged (because of possible view
2912 -- conversions), unless compiling for a VM where tags are
2915 -- tmp.comp._tag := comp_typ'tag;
2917 if Is_Tagged_Type
(Comp_Type
)
2918 and then Tagged_Type_Expansion
2921 Make_OK_Assignment_Statement
(Loc
,
2923 Make_Selected_Component
(Loc
,
2924 Prefix
=> New_Copy_Tree
(Comp_Expr
),
2927 (First_Tag_Component
(Comp_Type
), Loc
)),
2930 Unchecked_Convert_To
(RTE
(RE_Tag
),
2932 (Node
(First_Elmt
(Access_Disp_Table
(Comp_Type
))),
2935 Append_To
(L
, Instr
);
2939 -- Adjust (tmp.comp);
2941 if Needs_Finalization
(Comp_Type
)
2942 and then not Is_Limited_Type
(Comp_Type
)
2946 (Obj_Ref
=> New_Copy_Tree
(Comp_Expr
),
2951 -- comment would be good here ???
2953 elsif Ekind
(Selector
) = E_Discriminant
2954 and then Nkind
(N
) /= N_Extension_Aggregate
2955 and then Nkind
(Parent
(N
)) = N_Component_Association
2956 and then Is_Constrained
(Typ
)
2958 -- We must check that the discriminant value imposed by the
2959 -- context is the same as the value given in the subaggregate,
2960 -- because after the expansion into assignments there is no
2961 -- record on which to perform a regular discriminant check.
2968 D_Val
:= First_Elmt
(Discriminant_Constraint
(Typ
));
2969 Disc
:= First_Discriminant
(Typ
);
2970 while Chars
(Disc
) /= Chars
(Selector
) loop
2971 Next_Discriminant
(Disc
);
2975 pragma Assert
(Present
(D_Val
));
2977 -- This check cannot performed for components that are
2978 -- constrained by a current instance, because this is not a
2979 -- value that can be compared with the actual constraint.
2981 if Nkind
(Node
(D_Val
)) /= N_Attribute_Reference
2982 or else not Is_Entity_Name
(Prefix
(Node
(D_Val
)))
2983 or else not Is_Type
(Entity
(Prefix
(Node
(D_Val
))))
2986 Make_Raise_Constraint_Error
(Loc
,
2989 Left_Opnd
=> New_Copy_Tree
(Node
(D_Val
)),
2990 Right_Opnd
=> Expression
(Comp
)),
2991 Reason
=> CE_Discriminant_Check_Failed
));
2994 -- Find self-reference in previous discriminant assignment,
2995 -- and replace with proper expression.
3002 while Present
(Ass
) loop
3003 if Nkind
(Ass
) = N_Assignment_Statement
3004 and then Nkind
(Name
(Ass
)) = N_Selected_Component
3005 and then Chars
(Selector_Name
(Name
(Ass
))) =
3009 (Ass
, New_Copy_Tree
(Expression
(Comp
)));
3022 -- If the type is tagged, the tag needs to be initialized (unless we
3023 -- are in VM-mode where tags are implicit). It is done late in the
3024 -- initialization process because in some cases, we call the init
3025 -- proc of an ancestor which will not leave out the right tag.
3027 if Ancestor_Is_Expression
then
3030 -- For CPP types we generated a call to the C++ default constructor
3031 -- before the components have been initialized to ensure the proper
3032 -- initialization of the _Tag component (see above).
3034 elsif Is_CPP_Class
(Typ
) then
3037 elsif Is_Tagged_Type
(Typ
) and then Tagged_Type_Expansion
then
3039 Make_OK_Assignment_Statement
(Loc
,
3041 Make_Selected_Component
(Loc
,
3042 Prefix
=> New_Copy_Tree
(Target
),
3045 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
3048 Unchecked_Convert_To
(RTE
(RE_Tag
),
3050 (Node
(First_Elmt
(Access_Disp_Table
(Base_Type
(Typ
)))),
3053 Append_To
(L
, Instr
);
3055 -- Ada 2005 (AI-251): If the tagged type has been derived from an
3056 -- abstract interfaces we must also initialize the tags of the
3057 -- secondary dispatch tables.
3059 if Has_Interfaces
(Base_Type
(Typ
)) then
3061 (Typ
=> Base_Type
(Typ
),
3067 -- If the controllers have not been initialized yet (by lack of non-
3068 -- discriminant components), let's do it now.
3070 Generate_Finalization_Actions
;
3073 end Build_Record_Aggr_Code
;
3075 ---------------------------------------
3076 -- Collect_Initialization_Statements --
3077 ---------------------------------------
3079 procedure Collect_Initialization_Statements
3082 Node_After
: Node_Id
)
3084 Loc
: constant Source_Ptr
:= Sloc
(N
);
3085 Init_Actions
: constant List_Id
:= New_List
;
3086 Init_Node
: Node_Id
;
3087 Comp_Stmt
: Node_Id
;
3090 -- Nothing to do if Obj is already frozen, as in this case we known we
3091 -- won't need to move the initialization statements about later on.
3093 if Is_Frozen
(Obj
) then
3098 while Next
(Init_Node
) /= Node_After
loop
3099 Append_To
(Init_Actions
, Remove_Next
(Init_Node
));
3102 if not Is_Empty_List
(Init_Actions
) then
3103 Comp_Stmt
:= Make_Compound_Statement
(Loc
, Actions
=> Init_Actions
);
3104 Insert_Action_After
(Init_Node
, Comp_Stmt
);
3105 Set_Initialization_Statements
(Obj
, Comp_Stmt
);
3107 end Collect_Initialization_Statements
;
3109 -------------------------------
3110 -- Convert_Aggr_In_Allocator --
3111 -------------------------------
3113 procedure Convert_Aggr_In_Allocator
3118 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3119 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3120 Temp
: constant Entity_Id
:= Defining_Identifier
(Decl
);
3122 Occ
: constant Node_Id
:=
3123 Unchecked_Convert_To
(Typ
,
3124 Make_Explicit_Dereference
(Loc
, New_Occurrence_Of
(Temp
, Loc
)));
3127 if Is_Array_Type
(Typ
) then
3128 Convert_Array_Aggr_In_Allocator
(Decl
, Aggr
, Occ
);
3130 elsif Has_Default_Init_Comps
(Aggr
) then
3132 L
: constant List_Id
:= New_List
;
3133 Init_Stmts
: List_Id
;
3136 Init_Stmts
:= Late_Expansion
(Aggr
, Typ
, Occ
);
3138 if Has_Task
(Typ
) then
3139 Build_Task_Allocate_Block_With_Init_Stmts
(L
, Aggr
, Init_Stmts
);
3140 Insert_Actions
(Alloc
, L
);
3142 Insert_Actions
(Alloc
, Init_Stmts
);
3147 Insert_Actions
(Alloc
, Late_Expansion
(Aggr
, Typ
, Occ
));
3149 end Convert_Aggr_In_Allocator
;
3151 --------------------------------
3152 -- Convert_Aggr_In_Assignment --
3153 --------------------------------
3155 procedure Convert_Aggr_In_Assignment
(N
: Node_Id
) is
3156 Aggr
: Node_Id
:= Expression
(N
);
3157 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3158 Occ
: constant Node_Id
:= New_Copy_Tree
(Name
(N
));
3161 if Nkind
(Aggr
) = N_Qualified_Expression
then
3162 Aggr
:= Expression
(Aggr
);
3165 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3166 end Convert_Aggr_In_Assignment
;
3168 ---------------------------------
3169 -- Convert_Aggr_In_Object_Decl --
3170 ---------------------------------
3172 procedure Convert_Aggr_In_Object_Decl
(N
: Node_Id
) is
3173 Obj
: constant Entity_Id
:= Defining_Identifier
(N
);
3174 Aggr
: Node_Id
:= Expression
(N
);
3175 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3176 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3177 Occ
: constant Node_Id
:= New_Occurrence_Of
(Obj
, Loc
);
3179 function Discriminants_Ok
return Boolean;
3180 -- If the object type is constrained, the discriminants in the
3181 -- aggregate must be checked against the discriminants of the subtype.
3182 -- This cannot be done using Apply_Discriminant_Checks because after
3183 -- expansion there is no aggregate left to check.
3185 ----------------------
3186 -- Discriminants_Ok --
3187 ----------------------
3189 function Discriminants_Ok
return Boolean is
3190 Cond
: Node_Id
:= Empty
;
3199 D
:= First_Discriminant
(Typ
);
3200 Disc1
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3201 Disc2
:= First_Elmt
(Discriminant_Constraint
(Etype
(Obj
)));
3202 while Present
(Disc1
) and then Present
(Disc2
) loop
3203 Val1
:= Node
(Disc1
);
3204 Val2
:= Node
(Disc2
);
3206 if not Is_OK_Static_Expression
(Val1
)
3207 or else not Is_OK_Static_Expression
(Val2
)
3209 Check
:= Make_Op_Ne
(Loc
,
3210 Left_Opnd
=> Duplicate_Subexpr
(Val1
),
3211 Right_Opnd
=> Duplicate_Subexpr
(Val2
));
3217 Cond
:= Make_Or_Else
(Loc
,
3219 Right_Opnd
=> Check
);
3222 elsif Expr_Value
(Val1
) /= Expr_Value
(Val2
) then
3223 Apply_Compile_Time_Constraint_Error
(Aggr
,
3224 Msg
=> "incorrect value for discriminant&??",
3225 Reason
=> CE_Discriminant_Check_Failed
,
3230 Next_Discriminant
(D
);
3235 -- If any discriminant constraint is non-static, emit a check
3237 if Present
(Cond
) then
3239 Make_Raise_Constraint_Error
(Loc
,
3241 Reason
=> CE_Discriminant_Check_Failed
));
3245 end Discriminants_Ok
;
3247 -- Start of processing for Convert_Aggr_In_Object_Decl
3250 Set_Assignment_OK
(Occ
);
3252 if Nkind
(Aggr
) = N_Qualified_Expression
then
3253 Aggr
:= Expression
(Aggr
);
3256 if Has_Discriminants
(Typ
)
3257 and then Typ
/= Etype
(Obj
)
3258 and then Is_Constrained
(Etype
(Obj
))
3259 and then not Discriminants_Ok
3264 -- If the context is an extended return statement, it has its own
3265 -- finalization machinery (i.e. works like a transient scope) and
3266 -- we do not want to create an additional one, because objects on
3267 -- the finalization list of the return must be moved to the caller's
3268 -- finalization list to complete the return.
3270 -- However, if the aggregate is limited, it is built in place, and the
3271 -- controlled components are not assigned to intermediate temporaries
3272 -- so there is no need for a transient scope in this case either.
3274 if Requires_Transient_Scope
(Typ
)
3275 and then Ekind
(Current_Scope
) /= E_Return_Statement
3276 and then not Is_Limited_Type
(Typ
)
3278 Establish_Transient_Scope
3281 Is_Controlled
(Typ
) or else Has_Controlled_Component
(Typ
));
3285 Node_After
: constant Node_Id
:= Next
(N
);
3287 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3288 Collect_Initialization_Statements
(Obj
, N
, Node_After
);
3290 Set_No_Initialization
(N
);
3291 Initialize_Discriminants
(N
, Typ
);
3292 end Convert_Aggr_In_Object_Decl
;
3294 -------------------------------------
3295 -- Convert_Array_Aggr_In_Allocator --
3296 -------------------------------------
3298 procedure Convert_Array_Aggr_In_Allocator
3303 Aggr_Code
: List_Id
;
3304 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3305 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
3308 -- The target is an explicit dereference of the allocated object.
3309 -- Generate component assignments to it, as for an aggregate that
3310 -- appears on the right-hand side of an assignment statement.
3313 Build_Array_Aggr_Code
(Aggr
,
3315 Index
=> First_Index
(Typ
),
3317 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
3319 Insert_Actions_After
(Decl
, Aggr_Code
);
3320 end Convert_Array_Aggr_In_Allocator
;
3322 ----------------------------
3323 -- Convert_To_Assignments --
3324 ----------------------------
3326 procedure Convert_To_Assignments
(N
: Node_Id
; Typ
: Entity_Id
) is
3327 Loc
: constant Source_Ptr
:= Sloc
(N
);
3331 Aggr_Code
: List_Id
;
3333 Target_Expr
: Node_Id
;
3334 Parent_Kind
: Node_Kind
;
3335 Unc_Decl
: Boolean := False;
3336 Parent_Node
: Node_Id
;
3339 pragma Assert
(not Is_Static_Dispatch_Table_Aggregate
(N
));
3340 pragma Assert
(Is_Record_Type
(Typ
));
3342 Parent_Node
:= Parent
(N
);
3343 Parent_Kind
:= Nkind
(Parent_Node
);
3345 if Parent_Kind
= N_Qualified_Expression
then
3347 -- Check if we are in a unconstrained declaration because in this
3348 -- case the current delayed expansion mechanism doesn't work when
3349 -- the declared object size depend on the initializing expr.
3352 Parent_Node
:= Parent
(Parent_Node
);
3353 Parent_Kind
:= Nkind
(Parent_Node
);
3355 if Parent_Kind
= N_Object_Declaration
then
3357 not Is_Entity_Name
(Object_Definition
(Parent_Node
))
3358 or else Has_Discriminants
3359 (Entity
(Object_Definition
(Parent_Node
)))
3360 or else Is_Class_Wide_Type
3361 (Entity
(Object_Definition
(Parent_Node
)));
3366 -- Just set the Delay flag in the cases where the transformation will be
3367 -- done top down from above.
3371 -- Internal aggregate (transformed when expanding the parent)
3373 or else Parent_Kind
= N_Aggregate
3374 or else Parent_Kind
= N_Extension_Aggregate
3375 or else Parent_Kind
= N_Component_Association
3377 -- Allocator (see Convert_Aggr_In_Allocator)
3379 or else Parent_Kind
= N_Allocator
3381 -- Object declaration (see Convert_Aggr_In_Object_Decl)
3383 or else (Parent_Kind
= N_Object_Declaration
and then not Unc_Decl
)
3385 -- Safe assignment (see Convert_Aggr_Assignments). So far only the
3386 -- assignments in init procs are taken into account.
3388 or else (Parent_Kind
= N_Assignment_Statement
3389 and then Inside_Init_Proc
)
3391 -- (Ada 2005) An inherently limited type in a return statement, which
3392 -- will be handled in a build-in-place fashion, and may be rewritten
3393 -- as an extended return and have its own finalization machinery.
3394 -- In the case of a simple return, the aggregate needs to be delayed
3395 -- until the scope for the return statement has been created, so
3396 -- that any finalization chain will be associated with that scope.
3397 -- For extended returns, we delay expansion to avoid the creation
3398 -- of an unwanted transient scope that could result in premature
3399 -- finalization of the return object (which is built in place
3400 -- within the caller's scope).
3403 (Is_Limited_View
(Typ
)
3405 (Nkind
(Parent
(Parent_Node
)) = N_Extended_Return_Statement
3406 or else Nkind
(Parent_Node
) = N_Simple_Return_Statement
))
3408 Set_Expansion_Delayed
(N
);
3412 -- Otherwise, if a transient scope is required, create it now. If we
3413 -- are within an initialization procedure do not create such, because
3414 -- the target of the assignment must not be declared within a local
3415 -- block, and because cleanup will take place on return from the
3416 -- initialization procedure.
3417 -- Should the condition be more restrictive ???
3419 if Requires_Transient_Scope
(Typ
) and then not Inside_Init_Proc
then
3420 Establish_Transient_Scope
(N
, Sec_Stack
=> Needs_Finalization
(Typ
));
3423 -- If the aggregate is non-limited, create a temporary. If it is limited
3424 -- and context is an assignment, this is a subaggregate for an enclosing
3425 -- aggregate being expanded. It must be built in place, so use target of
3426 -- the current assignment.
3428 if Is_Limited_Type
(Typ
)
3429 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
3431 Target_Expr
:= New_Copy_Tree
(Name
(Parent
(N
)));
3432 Insert_Actions
(Parent
(N
),
3433 Build_Record_Aggr_Code
(N
, Typ
, Target_Expr
));
3434 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
3437 Temp
:= Make_Temporary
(Loc
, 'A', N
);
3439 -- If the type inherits unknown discriminants, use the view with
3440 -- known discriminants if available.
3442 if Has_Unknown_Discriminants
(Typ
)
3443 and then Present
(Underlying_Record_View
(Typ
))
3445 T
:= Underlying_Record_View
(Typ
);
3451 Make_Object_Declaration
(Loc
,
3452 Defining_Identifier
=> Temp
,
3453 Object_Definition
=> New_Occurrence_Of
(T
, Loc
));
3455 Set_No_Initialization
(Instr
);
3456 Insert_Action
(N
, Instr
);
3457 Initialize_Discriminants
(Instr
, T
);
3459 Target_Expr
:= New_Occurrence_Of
(Temp
, Loc
);
3460 Aggr_Code
:= Build_Record_Aggr_Code
(N
, T
, Target_Expr
);
3462 -- Save the last assignment statement associated with the aggregate
3463 -- when building a controlled object. This reference is utilized by
3464 -- the finalization machinery when marking an object as successfully
3467 if Needs_Finalization
(T
) then
3468 Set_Last_Aggregate_Assignment
(Temp
, Last
(Aggr_Code
));
3471 Insert_Actions
(N
, Aggr_Code
);
3472 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
3473 Analyze_And_Resolve
(N
, T
);
3475 end Convert_To_Assignments
;
3477 ---------------------------
3478 -- Convert_To_Positional --
3479 ---------------------------
3481 procedure Convert_To_Positional
3483 Max_Others_Replicate
: Nat
:= 5;
3484 Handle_Bit_Packed
: Boolean := False)
3486 Typ
: constant Entity_Id
:= Etype
(N
);
3488 Static_Components
: Boolean := True;
3490 procedure Check_Static_Components
;
3491 -- Check whether all components of the aggregate are compile-time known
3492 -- values, and can be passed as is to the back-end without further
3498 Ixb
: Node_Id
) return Boolean;
3499 -- Convert the aggregate into a purely positional form if possible. On
3500 -- entry the bounds of all dimensions are known to be static, and the
3501 -- total number of components is safe enough to expand.
3503 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean;
3504 -- Return True iff the array N is flat (which is not trivial in the case
3505 -- of multidimensional aggregates).
3507 -----------------------------
3508 -- Check_Static_Components --
3509 -----------------------------
3511 -- Could use some comments in this body ???
3513 procedure Check_Static_Components
is
3517 Static_Components
:= True;
3519 if Nkind
(N
) = N_String_Literal
then
3522 elsif Present
(Expressions
(N
)) then
3523 Expr
:= First
(Expressions
(N
));
3524 while Present
(Expr
) loop
3525 if Nkind
(Expr
) /= N_Aggregate
3526 or else not Compile_Time_Known_Aggregate
(Expr
)
3527 or else Expansion_Delayed
(Expr
)
3529 Static_Components
:= False;
3537 if Nkind
(N
) = N_Aggregate
3538 and then Present
(Component_Associations
(N
))
3540 Expr
:= First
(Component_Associations
(N
));
3541 while Present
(Expr
) loop
3542 if Nkind_In
(Expression
(Expr
), N_Integer_Literal
,
3547 elsif Is_Entity_Name
(Expression
(Expr
))
3548 and then Present
(Entity
(Expression
(Expr
)))
3549 and then Ekind
(Entity
(Expression
(Expr
))) =
3550 E_Enumeration_Literal
3554 elsif Nkind
(Expression
(Expr
)) /= N_Aggregate
3555 or else not Compile_Time_Known_Aggregate
(Expression
(Expr
))
3556 or else Expansion_Delayed
(Expression
(Expr
))
3558 Static_Components
:= False;
3565 end Check_Static_Components
;
3574 Ixb
: Node_Id
) return Boolean
3576 Loc
: constant Source_Ptr
:= Sloc
(N
);
3577 Blo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ixb
));
3578 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ix
));
3579 Hi
: constant Node_Id
:= Type_High_Bound
(Etype
(Ix
));
3583 Others_Present
: Boolean := False;
3586 if Nkind
(Original_Node
(N
)) = N_String_Literal
then
3590 if not Compile_Time_Known_Value
(Lo
)
3591 or else not Compile_Time_Known_Value
(Hi
)
3596 Lov
:= Expr_Value
(Lo
);
3597 Hiv
:= Expr_Value
(Hi
);
3599 -- Check if there is an others choice
3601 if Present
(Component_Associations
(N
)) then
3607 Assoc
:= First
(Component_Associations
(N
));
3608 while Present
(Assoc
) loop
3610 -- If this is a box association, flattening is in general
3611 -- not possible because at this point we cannot tell if the
3612 -- default is static or even exists.
3614 if Box_Present
(Assoc
) then
3618 Choice
:= First
(Choices
(Assoc
));
3620 while Present
(Choice
) loop
3621 if Nkind
(Choice
) = N_Others_Choice
then
3622 Others_Present
:= True;
3633 -- If the low bound is not known at compile time and others is not
3634 -- present we can proceed since the bounds can be obtained from the
3637 -- Note: This case is required in VM platforms since their backends
3638 -- normalize array indexes in the range 0 .. N-1. Hence, if we do
3639 -- not flat an array whose bounds cannot be obtained from the type
3640 -- of the index the backend has no way to properly generate the code.
3641 -- See ACATS c460010 for an example.
3644 or else (not Compile_Time_Known_Value
(Blo
) and then Others_Present
)
3649 -- Determine if set of alternatives is suitable for conversion and
3650 -- build an array containing the values in sequence.
3653 Vals
: array (UI_To_Int
(Lov
) .. UI_To_Int
(Hiv
))
3654 of Node_Id
:= (others => Empty
);
3655 -- The values in the aggregate sorted appropriately
3658 -- Same data as Vals in list form
3661 -- Used to validate Max_Others_Replicate limit
3664 Num
: Int
:= UI_To_Int
(Lov
);
3670 if Present
(Expressions
(N
)) then
3671 Elmt
:= First
(Expressions
(N
));
3672 while Present
(Elmt
) loop
3673 if Nkind
(Elmt
) = N_Aggregate
3674 and then Present
(Next_Index
(Ix
))
3676 not Flatten
(Elmt
, Next_Index
(Ix
), Next_Index
(Ixb
))
3681 Vals
(Num
) := Relocate_Node
(Elmt
);
3688 if No
(Component_Associations
(N
)) then
3692 Elmt
:= First
(Component_Associations
(N
));
3694 if Nkind
(Expression
(Elmt
)) = N_Aggregate
then
3695 if Present
(Next_Index
(Ix
))
3698 (Expression
(Elmt
), Next_Index
(Ix
), Next_Index
(Ixb
))
3704 Component_Loop
: while Present
(Elmt
) loop
3705 Choice
:= First
(Choices
(Elmt
));
3706 Choice_Loop
: while Present
(Choice
) loop
3708 -- If we have an others choice, fill in the missing elements
3709 -- subject to the limit established by Max_Others_Replicate.
3711 if Nkind
(Choice
) = N_Others_Choice
then
3714 for J
in Vals
'Range loop
3715 if No
(Vals
(J
)) then
3716 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
3717 Rep_Count
:= Rep_Count
+ 1;
3719 -- Check for maximum others replication. Note that
3720 -- we skip this test if either of the restrictions
3721 -- No_Elaboration_Code or No_Implicit_Loops is
3722 -- active, if this is a preelaborable unit or
3723 -- a predefined unit, or if the unit must be
3724 -- placed in data memory. This also ensures that
3725 -- predefined units get the same level of constant
3726 -- folding in Ada 95 and Ada 2005, where their
3727 -- categorization has changed.
3730 P
: constant Entity_Id
:=
3731 Cunit_Entity
(Current_Sem_Unit
);
3734 -- Check if duplication OK and if so continue
3737 if Restriction_Active
(No_Elaboration_Code
)
3738 or else Restriction_Active
(No_Implicit_Loops
)
3740 (Ekind
(Current_Scope
) = E_Package
3741 and then Static_Elaboration_Desired
3743 or else Is_Preelaborated
(P
)
3744 or else (Ekind
(P
) = E_Package_Body
3746 Is_Preelaborated
(Spec_Entity
(P
)))
3748 Is_Predefined_File_Name
3749 (Unit_File_Name
(Get_Source_Unit
(P
)))
3753 -- If duplication not OK, then we return False
3754 -- if the replication count is too high
3756 elsif Rep_Count
> Max_Others_Replicate
then
3759 -- Continue on if duplication not OK, but the
3760 -- replication count is not excessive.
3769 exit Component_Loop
;
3771 -- Case of a subtype mark, identifier or expanded name
3773 elsif Is_Entity_Name
(Choice
)
3774 and then Is_Type
(Entity
(Choice
))
3776 Lo
:= Type_Low_Bound
(Etype
(Choice
));
3777 Hi
:= Type_High_Bound
(Etype
(Choice
));
3779 -- Case of subtype indication
3781 elsif Nkind
(Choice
) = N_Subtype_Indication
then
3782 Lo
:= Low_Bound
(Range_Expression
(Constraint
(Choice
)));
3783 Hi
:= High_Bound
(Range_Expression
(Constraint
(Choice
)));
3787 elsif Nkind
(Choice
) = N_Range
then
3788 Lo
:= Low_Bound
(Choice
);
3789 Hi
:= High_Bound
(Choice
);
3791 -- Normal subexpression case
3793 else pragma Assert
(Nkind
(Choice
) in N_Subexpr
);
3794 if not Compile_Time_Known_Value
(Choice
) then
3798 Choice_Index
:= UI_To_Int
(Expr_Value
(Choice
));
3800 if Choice_Index
in Vals
'Range then
3801 Vals
(Choice_Index
) :=
3802 New_Copy_Tree
(Expression
(Elmt
));
3805 -- Choice is statically out-of-range, will be
3806 -- rewritten to raise Constraint_Error.
3814 -- Range cases merge with Lo,Hi set
3816 if not Compile_Time_Known_Value
(Lo
)
3818 not Compile_Time_Known_Value
(Hi
)
3823 for J
in UI_To_Int
(Expr_Value
(Lo
)) ..
3824 UI_To_Int
(Expr_Value
(Hi
))
3826 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
3832 end loop Choice_Loop
;
3835 end loop Component_Loop
;
3837 -- If we get here the conversion is possible
3840 for J
in Vals
'Range loop
3841 Append
(Vals
(J
), Vlist
);
3844 Rewrite
(N
, Make_Aggregate
(Loc
, Expressions
=> Vlist
));
3845 Set_Aggregate_Bounds
(N
, Aggregate_Bounds
(Original_Node
(N
)));
3854 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean is
3861 elsif Nkind
(N
) = N_Aggregate
then
3862 if Present
(Component_Associations
(N
)) then
3866 Elmt
:= First
(Expressions
(N
));
3867 while Present
(Elmt
) loop
3868 if not Is_Flat
(Elmt
, Dims
- 1) then
3882 -- Start of processing for Convert_To_Positional
3885 -- Ada 2005 (AI-287): Do not convert in case of default initialized
3886 -- components because in this case will need to call the corresponding
3889 if Has_Default_Init_Comps
(N
) then
3893 if Is_Flat
(N
, Number_Dimensions
(Typ
)) then
3897 if Is_Bit_Packed_Array
(Typ
) and then not Handle_Bit_Packed
then
3901 -- Do not convert to positional if controlled components are involved
3902 -- since these require special processing
3904 if Has_Controlled_Component
(Typ
) then
3908 Check_Static_Components
;
3910 -- If the size is known, or all the components are static, try to
3911 -- build a fully positional aggregate.
3913 -- The size of the type may not be known for an aggregate with
3914 -- discriminated array components, but if the components are static
3915 -- it is still possible to verify statically that the length is
3916 -- compatible with the upper bound of the type, and therefore it is
3917 -- worth flattening such aggregates as well.
3919 -- For now the back-end expands these aggregates into individual
3920 -- assignments to the target anyway, but it is conceivable that
3921 -- it will eventually be able to treat such aggregates statically???
3923 if Aggr_Size_OK
(N
, Typ
)
3924 and then Flatten
(N
, First_Index
(Typ
), First_Index
(Base_Type
(Typ
)))
3926 if Static_Components
then
3927 Set_Compile_Time_Known_Aggregate
(N
);
3928 Set_Expansion_Delayed
(N
, False);
3931 Analyze_And_Resolve
(N
, Typ
);
3934 -- Is Static_Eaboration_Desired has been specified, diagnose aggregates
3935 -- that will still require initialization code.
3937 if (Ekind
(Current_Scope
) = E_Package
3938 and then Static_Elaboration_Desired
(Current_Scope
))
3939 and then Nkind
(Parent
(N
)) = N_Object_Declaration
3945 if Nkind
(N
) = N_Aggregate
and then Present
(Expressions
(N
)) then
3946 Expr
:= First
(Expressions
(N
));
3947 while Present
(Expr
) loop
3948 if Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
)
3950 (Is_Entity_Name
(Expr
)
3951 and then Ekind
(Entity
(Expr
)) = E_Enumeration_Literal
)
3957 ("non-static object requires elaboration code??", N
);
3964 if Present
(Component_Associations
(N
)) then
3965 Error_Msg_N
("object requires elaboration code??", N
);
3970 end Convert_To_Positional
;
3972 ----------------------------
3973 -- Expand_Array_Aggregate --
3974 ----------------------------
3976 -- Array aggregate expansion proceeds as follows:
3978 -- 1. If requested we generate code to perform all the array aggregate
3979 -- bound checks, specifically
3981 -- (a) Check that the index range defined by aggregate bounds is
3982 -- compatible with corresponding index subtype.
3984 -- (b) If an others choice is present check that no aggregate
3985 -- index is outside the bounds of the index constraint.
3987 -- (c) For multidimensional arrays make sure that all subaggregates
3988 -- corresponding to the same dimension have the same bounds.
3990 -- 2. Check for packed array aggregate which can be converted to a
3991 -- constant so that the aggregate disappears completely.
3993 -- 3. Check case of nested aggregate. Generally nested aggregates are
3994 -- handled during the processing of the parent aggregate.
3996 -- 4. Check if the aggregate can be statically processed. If this is the
3997 -- case pass it as is to Gigi. Note that a necessary condition for
3998 -- static processing is that the aggregate be fully positional.
4000 -- 5. If in place aggregate expansion is possible (i.e. no need to create
4001 -- a temporary) then mark the aggregate as such and return. Otherwise
4002 -- create a new temporary and generate the appropriate initialization
4005 procedure Expand_Array_Aggregate
(N
: Node_Id
) is
4006 Loc
: constant Source_Ptr
:= Sloc
(N
);
4008 Typ
: constant Entity_Id
:= Etype
(N
);
4009 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
4010 -- Typ is the correct constrained array subtype of the aggregate
4011 -- Ctyp is the corresponding component type.
4013 Aggr_Dimension
: constant Pos
:= Number_Dimensions
(Typ
);
4014 -- Number of aggregate index dimensions
4016 Aggr_Low
: array (1 .. Aggr_Dimension
) of Node_Id
;
4017 Aggr_High
: array (1 .. Aggr_Dimension
) of Node_Id
;
4018 -- Low and High bounds of the constraint for each aggregate index
4020 Aggr_Index_Typ
: array (1 .. Aggr_Dimension
) of Entity_Id
;
4021 -- The type of each index
4023 In_Place_Assign_OK_For_Declaration
: Boolean := False;
4024 -- True if we are to generate an in place assignment for a declaration
4026 Maybe_In_Place_OK
: Boolean;
4027 -- If the type is neither controlled nor packed and the aggregate
4028 -- is the expression in an assignment, assignment in place may be
4029 -- possible, provided other conditions are met on the LHS.
4031 Others_Present
: array (1 .. Aggr_Dimension
) of Boolean :=
4033 -- If Others_Present (J) is True, then there is an others choice
4034 -- in one of the sub-aggregates of N at dimension J.
4036 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean;
4037 -- Returns true if an aggregate assignment can be done by the back end
4039 procedure Build_Constrained_Type
(Positional
: Boolean);
4040 -- If the subtype is not static or unconstrained, build a constrained
4041 -- type using the computable sizes of the aggregate and its sub-
4044 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
);
4045 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
4048 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4049 -- Checks that in a multi-dimensional array aggregate all subaggregates
4050 -- corresponding to the same dimension have the same bounds.
4051 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4052 -- corresponding to the sub-aggregate.
4054 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4055 -- Computes the values of array Others_Present. Sub_Aggr is the
4056 -- array sub-aggregate we start the computation from. Dim is the
4057 -- dimension corresponding to the sub-aggregate.
4059 function In_Place_Assign_OK
return Boolean;
4060 -- Simple predicate to determine whether an aggregate assignment can
4061 -- be done in place, because none of the new values can depend on the
4062 -- components of the target of the assignment.
4064 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4065 -- Checks that if an others choice is present in any sub-aggregate no
4066 -- aggregate index is outside the bounds of the index constraint.
4067 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4068 -- corresponding to the sub-aggregate.
4070 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean;
4071 -- In addition to Maybe_In_Place_OK, in order for an aggregate to be
4072 -- built directly into the target of the assignment it must be free
4075 ------------------------------------
4076 -- Aggr_Assignment_OK_For_Backend --
4077 ------------------------------------
4079 -- Backend processing by Gigi/gcc is possible only if all the following
4080 -- conditions are met:
4082 -- 1. N consists of a single OTHERS choice, possibly recursively
4084 -- 2. The array type is not packed
4086 -- 3. The array type has no atomic components
4088 -- 4. The array type has no null ranges (the purpose of this is to
4089 -- avoid a bogus warning for an out-of-range value).
4091 -- 5. The component type is discrete
4093 -- 6. The component size is Storage_Unit or the value is of the form
4094 -- M * (1 + A**1 + A**2 + .. A**(K-1)) where A = 2**(Storage_Unit)
4095 -- and M in 1 .. A-1. This can also be viewed as K occurrences of
4096 -- the 8-bit value M, concatenated together.
4098 -- The ultimate goal is to generate a call to a fast memset routine
4099 -- specifically optimized for the target.
4101 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean is
4104 Expr
: Node_Id
:= N
;
4112 -- Recurse as far as possible to find the innermost component type
4115 while Is_Array_Type
(Ctyp
) loop
4116 if Nkind
(Expr
) /= N_Aggregate
4117 or else not Is_Others_Aggregate
(Expr
)
4122 if Present
(Packed_Array_Impl_Type
(Ctyp
)) then
4126 if Has_Atomic_Components
(Ctyp
) then
4130 Index
:= First_Index
(Ctyp
);
4131 while Present
(Index
) loop
4132 Get_Index_Bounds
(Index
, Low
, High
);
4134 if Is_Null_Range
(Low
, High
) then
4141 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4143 for J
in 1 .. Number_Dimensions
(Ctyp
) - 1 loop
4144 if Nkind
(Expr
) /= N_Aggregate
4145 or else not Is_Others_Aggregate
(Expr
)
4150 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4153 Ctyp
:= Component_Type
(Ctyp
);
4155 if Is_Atomic
(Ctyp
) then
4160 if not Is_Discrete_Type
(Ctyp
) then
4164 -- The expression needs to be analyzed if True is returned
4166 Analyze_And_Resolve
(Expr
, Ctyp
);
4168 -- The back end uses the Esize as the precision of the type
4170 Nunits
:= UI_To_Int
(Esize
(Ctyp
)) / System_Storage_Unit
;
4176 if not Compile_Time_Known_Value
(Expr
) then
4180 Value
:= Expr_Value
(Expr
);
4182 if Has_Biased_Representation
(Ctyp
) then
4183 Value
:= Value
- Expr_Value
(Type_Low_Bound
(Ctyp
));
4186 -- Values 0 and -1 immediately satisfy the last check
4188 if Value
= Uint_0
or else Value
= Uint_Minus_1
then
4192 -- We need to work with an unsigned value
4195 Value
:= Value
+ 2**(System_Storage_Unit
* Nunits
);
4198 Remainder
:= Value
rem 2**System_Storage_Unit
;
4200 for J
in 1 .. Nunits
- 1 loop
4201 Value
:= Value
/ 2**System_Storage_Unit
;
4203 if Value
rem 2**System_Storage_Unit
/= Remainder
then
4209 end Aggr_Assignment_OK_For_Backend
;
4211 ----------------------------
4212 -- Build_Constrained_Type --
4213 ----------------------------
4215 procedure Build_Constrained_Type
(Positional
: Boolean) is
4216 Loc
: constant Source_Ptr
:= Sloc
(N
);
4217 Agg_Type
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
4220 Typ
: constant Entity_Id
:= Etype
(N
);
4221 Indexes
: constant List_Id
:= New_List
;
4226 -- If the aggregate is purely positional, all its subaggregates
4227 -- have the same size. We collect the dimensions from the first
4228 -- subaggregate at each level.
4233 for D
in 1 .. Number_Dimensions
(Typ
) loop
4234 Sub_Agg
:= First
(Expressions
(Sub_Agg
));
4238 while Present
(Comp
) loop
4245 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
4246 High_Bound
=> Make_Integer_Literal
(Loc
, Num
)));
4250 -- We know the aggregate type is unconstrained and the aggregate
4251 -- is not processable by the back end, therefore not necessarily
4252 -- positional. Retrieve each dimension bounds (computed earlier).
4254 for D
in 1 .. Number_Dimensions
(Typ
) loop
4257 Low_Bound
=> Aggr_Low
(D
),
4258 High_Bound
=> Aggr_High
(D
)));
4263 Make_Full_Type_Declaration
(Loc
,
4264 Defining_Identifier
=> Agg_Type
,
4266 Make_Constrained_Array_Definition
(Loc
,
4267 Discrete_Subtype_Definitions
=> Indexes
,
4268 Component_Definition
=>
4269 Make_Component_Definition
(Loc
,
4270 Aliased_Present
=> False,
4271 Subtype_Indication
=>
4272 New_Occurrence_Of
(Component_Type
(Typ
), Loc
))));
4274 Insert_Action
(N
, Decl
);
4276 Set_Etype
(N
, Agg_Type
);
4277 Set_Is_Itype
(Agg_Type
);
4278 Freeze_Itype
(Agg_Type
, N
);
4279 end Build_Constrained_Type
;
4285 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
) is
4292 Cond
: Node_Id
:= Empty
;
4295 Get_Index_Bounds
(Aggr_Bounds
, Aggr_Lo
, Aggr_Hi
);
4296 Get_Index_Bounds
(Index_Bounds
, Ind_Lo
, Ind_Hi
);
4298 -- Generate the following test:
4300 -- [constraint_error when
4301 -- Aggr_Lo <= Aggr_Hi and then
4302 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
4304 -- As an optimization try to see if some tests are trivially vacuous
4305 -- because we are comparing an expression against itself.
4307 if Aggr_Lo
= Ind_Lo
and then Aggr_Hi
= Ind_Hi
then
4310 elsif Aggr_Hi
= Ind_Hi
then
4313 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4314 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
));
4316 elsif Aggr_Lo
= Ind_Lo
then
4319 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
4320 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Hi
));
4327 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4328 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
)),
4332 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
4333 Right_Opnd
=> Duplicate_Subexpr
(Ind_Hi
)));
4336 if Present
(Cond
) then
4341 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4342 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
)),
4344 Right_Opnd
=> Cond
);
4346 Set_Analyzed
(Left_Opnd
(Left_Opnd
(Cond
)), False);
4347 Set_Analyzed
(Right_Opnd
(Left_Opnd
(Cond
)), False);
4349 Make_Raise_Constraint_Error
(Loc
,
4351 Reason
=> CE_Range_Check_Failed
));
4355 ----------------------------
4356 -- Check_Same_Aggr_Bounds --
4357 ----------------------------
4359 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4360 Sub_Lo
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(Sub_Aggr
));
4361 Sub_Hi
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(Sub_Aggr
));
4362 -- The bounds of this specific sub-aggregate
4364 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
4365 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
4366 -- The bounds of the aggregate for this dimension
4368 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
4369 -- The index type for this dimension.xxx
4371 Cond
: Node_Id
:= Empty
;
4376 -- If index checks are on generate the test
4378 -- [constraint_error when
4379 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
4381 -- As an optimization try to see if some tests are trivially vacuos
4382 -- because we are comparing an expression against itself. Also for
4383 -- the first dimension the test is trivially vacuous because there
4384 -- is just one aggregate for dimension 1.
4386 if Index_Checks_Suppressed
(Ind_Typ
) then
4389 elsif Dim
= 1 or else (Aggr_Lo
= Sub_Lo
and then Aggr_Hi
= Sub_Hi
)
4393 elsif Aggr_Hi
= Sub_Hi
then
4396 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4397 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
));
4399 elsif Aggr_Lo
= Sub_Lo
then
4402 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
4403 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Hi
));
4410 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4411 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
)),
4415 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
4416 Right_Opnd
=> Duplicate_Subexpr
(Sub_Hi
)));
4419 if Present
(Cond
) then
4421 Make_Raise_Constraint_Error
(Loc
,
4423 Reason
=> CE_Length_Check_Failed
));
4426 -- Now look inside the sub-aggregate to see if there is more work
4428 if Dim
< Aggr_Dimension
then
4430 -- Process positional components
4432 if Present
(Expressions
(Sub_Aggr
)) then
4433 Expr
:= First
(Expressions
(Sub_Aggr
));
4434 while Present
(Expr
) loop
4435 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
4440 -- Process component associations
4442 if Present
(Component_Associations
(Sub_Aggr
)) then
4443 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4444 while Present
(Assoc
) loop
4445 Expr
:= Expression
(Assoc
);
4446 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
4451 end Check_Same_Aggr_Bounds
;
4453 ----------------------------
4454 -- Compute_Others_Present --
4455 ----------------------------
4457 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4462 if Present
(Component_Associations
(Sub_Aggr
)) then
4463 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
4465 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
then
4466 Others_Present
(Dim
) := True;
4470 -- Now look inside the sub-aggregate to see if there is more work
4472 if Dim
< Aggr_Dimension
then
4474 -- Process positional components
4476 if Present
(Expressions
(Sub_Aggr
)) then
4477 Expr
:= First
(Expressions
(Sub_Aggr
));
4478 while Present
(Expr
) loop
4479 Compute_Others_Present
(Expr
, Dim
+ 1);
4484 -- Process component associations
4486 if Present
(Component_Associations
(Sub_Aggr
)) then
4487 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4488 while Present
(Assoc
) loop
4489 Expr
:= Expression
(Assoc
);
4490 Compute_Others_Present
(Expr
, Dim
+ 1);
4495 end Compute_Others_Present
;
4497 ------------------------
4498 -- In_Place_Assign_OK --
4499 ------------------------
4501 function In_Place_Assign_OK
return Boolean is
4509 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean;
4510 -- Check recursively that each component of a (sub)aggregate does
4511 -- not depend on the variable being assigned to.
4513 function Safe_Component
(Expr
: Node_Id
) return Boolean;
4514 -- Verify that an expression cannot depend on the variable being
4515 -- assigned to. Room for improvement here (but less than before).
4517 --------------------
4518 -- Safe_Aggregate --
4519 --------------------
4521 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean is
4525 if Present
(Expressions
(Aggr
)) then
4526 Expr
:= First
(Expressions
(Aggr
));
4527 while Present
(Expr
) loop
4528 if Nkind
(Expr
) = N_Aggregate
then
4529 if not Safe_Aggregate
(Expr
) then
4533 elsif not Safe_Component
(Expr
) then
4541 if Present
(Component_Associations
(Aggr
)) then
4542 Expr
:= First
(Component_Associations
(Aggr
));
4543 while Present
(Expr
) loop
4544 if Nkind
(Expression
(Expr
)) = N_Aggregate
then
4545 if not Safe_Aggregate
(Expression
(Expr
)) then
4549 -- If association has a box, no way to determine yet
4550 -- whether default can be assigned in place.
4552 elsif Box_Present
(Expr
) then
4555 elsif not Safe_Component
(Expression
(Expr
)) then
4566 --------------------
4567 -- Safe_Component --
4568 --------------------
4570 function Safe_Component
(Expr
: Node_Id
) return Boolean is
4571 Comp
: Node_Id
:= Expr
;
4573 function Check_Component
(Comp
: Node_Id
) return Boolean;
4574 -- Do the recursive traversal, after copy
4576 ---------------------
4577 -- Check_Component --
4578 ---------------------
4580 function Check_Component
(Comp
: Node_Id
) return Boolean is
4582 if Is_Overloaded
(Comp
) then
4586 return Compile_Time_Known_Value
(Comp
)
4588 or else (Is_Entity_Name
(Comp
)
4589 and then Present
(Entity
(Comp
))
4590 and then No
(Renamed_Object
(Entity
(Comp
))))
4592 or else (Nkind
(Comp
) = N_Attribute_Reference
4593 and then Check_Component
(Prefix
(Comp
)))
4595 or else (Nkind
(Comp
) in N_Binary_Op
4596 and then Check_Component
(Left_Opnd
(Comp
))
4597 and then Check_Component
(Right_Opnd
(Comp
)))
4599 or else (Nkind
(Comp
) in N_Unary_Op
4600 and then Check_Component
(Right_Opnd
(Comp
)))
4602 or else (Nkind
(Comp
) = N_Selected_Component
4603 and then Check_Component
(Prefix
(Comp
)))
4605 or else (Nkind
(Comp
) = N_Unchecked_Type_Conversion
4606 and then Check_Component
(Expression
(Comp
)));
4607 end Check_Component
;
4609 -- Start of processing for Safe_Component
4612 -- If the component appears in an association that may correspond
4613 -- to more than one element, it is not analyzed before expansion
4614 -- into assignments, to avoid side effects. We analyze, but do not
4615 -- resolve the copy, to obtain sufficient entity information for
4616 -- the checks that follow. If component is overloaded we assume
4617 -- an unsafe function call.
4619 if not Analyzed
(Comp
) then
4620 if Is_Overloaded
(Expr
) then
4623 elsif Nkind
(Expr
) = N_Aggregate
4624 and then not Is_Others_Aggregate
(Expr
)
4628 elsif Nkind
(Expr
) = N_Allocator
then
4630 -- For now, too complex to analyze
4635 Comp
:= New_Copy_Tree
(Expr
);
4636 Set_Parent
(Comp
, Parent
(Expr
));
4640 if Nkind
(Comp
) = N_Aggregate
then
4641 return Safe_Aggregate
(Comp
);
4643 return Check_Component
(Comp
);
4647 -- Start of processing for In_Place_Assign_OK
4650 if Present
(Component_Associations
(N
)) then
4652 -- On assignment, sliding can take place, so we cannot do the
4653 -- assignment in place unless the bounds of the aggregate are
4654 -- statically equal to those of the target.
4656 -- If the aggregate is given by an others choice, the bounds are
4657 -- derived from the left-hand side, and the assignment is safe if
4658 -- the expression is.
4660 if Is_Others_Aggregate
(N
) then
4663 (Expression
(First
(Component_Associations
(N
))));
4666 Aggr_In
:= First_Index
(Etype
(N
));
4668 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
4669 Obj_In
:= First_Index
(Etype
(Name
(Parent
(N
))));
4672 -- Context is an allocator. Check bounds of aggregate against
4673 -- given type in qualified expression.
4675 pragma Assert
(Nkind
(Parent
(Parent
(N
))) = N_Allocator
);
4677 First_Index
(Etype
(Entity
(Subtype_Mark
(Parent
(N
)))));
4680 while Present
(Aggr_In
) loop
4681 Get_Index_Bounds
(Aggr_In
, Aggr_Lo
, Aggr_Hi
);
4682 Get_Index_Bounds
(Obj_In
, Obj_Lo
, Obj_Hi
);
4684 if not Compile_Time_Known_Value
(Aggr_Lo
)
4685 or else not Compile_Time_Known_Value
(Aggr_Hi
)
4686 or else not Compile_Time_Known_Value
(Obj_Lo
)
4687 or else not Compile_Time_Known_Value
(Obj_Hi
)
4688 or else Expr_Value
(Aggr_Lo
) /= Expr_Value
(Obj_Lo
)
4689 or else Expr_Value
(Aggr_Hi
) /= Expr_Value
(Obj_Hi
)
4694 Next_Index
(Aggr_In
);
4695 Next_Index
(Obj_In
);
4699 -- Now check the component values themselves
4701 return Safe_Aggregate
(N
);
4702 end In_Place_Assign_OK
;
4708 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4709 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
4710 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
4711 -- The bounds of the aggregate for this dimension
4713 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
4714 -- The index type for this dimension
4716 Need_To_Check
: Boolean := False;
4718 Choices_Lo
: Node_Id
:= Empty
;
4719 Choices_Hi
: Node_Id
:= Empty
;
4720 -- The lowest and highest discrete choices for a named sub-aggregate
4722 Nb_Choices
: Int
:= -1;
4723 -- The number of discrete non-others choices in this sub-aggregate
4725 Nb_Elements
: Uint
:= Uint_0
;
4726 -- The number of elements in a positional aggregate
4728 Cond
: Node_Id
:= Empty
;
4735 -- Check if we have an others choice. If we do make sure that this
4736 -- sub-aggregate contains at least one element in addition to the
4739 if Range_Checks_Suppressed
(Ind_Typ
) then
4740 Need_To_Check
:= False;
4742 elsif Present
(Expressions
(Sub_Aggr
))
4743 and then Present
(Component_Associations
(Sub_Aggr
))
4745 Need_To_Check
:= True;
4747 elsif Present
(Component_Associations
(Sub_Aggr
)) then
4748 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
4750 if Nkind
(First
(Choices
(Assoc
))) /= N_Others_Choice
then
4751 Need_To_Check
:= False;
4754 -- Count the number of discrete choices. Start with -1 because
4755 -- the others choice does not count.
4757 -- Is there some reason we do not use List_Length here ???
4760 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4761 while Present
(Assoc
) loop
4762 Choice
:= First
(Choices
(Assoc
));
4763 while Present
(Choice
) loop
4764 Nb_Choices
:= Nb_Choices
+ 1;
4771 -- If there is only an others choice nothing to do
4773 Need_To_Check
:= (Nb_Choices
> 0);
4777 Need_To_Check
:= False;
4780 -- If we are dealing with a positional sub-aggregate with an others
4781 -- choice then compute the number or positional elements.
4783 if Need_To_Check
and then Present
(Expressions
(Sub_Aggr
)) then
4784 Expr
:= First
(Expressions
(Sub_Aggr
));
4785 Nb_Elements
:= Uint_0
;
4786 while Present
(Expr
) loop
4787 Nb_Elements
:= Nb_Elements
+ 1;
4791 -- If the aggregate contains discrete choices and an others choice
4792 -- compute the smallest and largest discrete choice values.
4794 elsif Need_To_Check
then
4795 Compute_Choices_Lo_And_Choices_Hi
: declare
4797 Table
: Case_Table_Type
(1 .. Nb_Choices
);
4798 -- Used to sort all the different choice values
4805 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4806 while Present
(Assoc
) loop
4807 Choice
:= First
(Choices
(Assoc
));
4808 while Present
(Choice
) loop
4809 if Nkind
(Choice
) = N_Others_Choice
then
4813 Get_Index_Bounds
(Choice
, Low
, High
);
4814 Table
(J
).Choice_Lo
:= Low
;
4815 Table
(J
).Choice_Hi
:= High
;
4824 -- Sort the discrete choices
4826 Sort_Case_Table
(Table
);
4828 Choices_Lo
:= Table
(1).Choice_Lo
;
4829 Choices_Hi
:= Table
(Nb_Choices
).Choice_Hi
;
4830 end Compute_Choices_Lo_And_Choices_Hi
;
4833 -- If no others choice in this sub-aggregate, or the aggregate
4834 -- comprises only an others choice, nothing to do.
4836 if not Need_To_Check
then
4839 -- If we are dealing with an aggregate containing an others choice
4840 -- and positional components, we generate the following test:
4842 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
4843 -- Ind_Typ'Pos (Aggr_Hi)
4845 -- raise Constraint_Error;
4848 elsif Nb_Elements
> Uint_0
then
4854 Make_Attribute_Reference
(Loc
,
4855 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
4856 Attribute_Name
=> Name_Pos
,
4859 (Duplicate_Subexpr_Move_Checks
(Aggr_Lo
))),
4860 Right_Opnd
=> Make_Integer_Literal
(Loc
, Nb_Elements
- 1)),
4863 Make_Attribute_Reference
(Loc
,
4864 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
4865 Attribute_Name
=> Name_Pos
,
4866 Expressions
=> New_List
(
4867 Duplicate_Subexpr_Move_Checks
(Aggr_Hi
))));
4869 -- If we are dealing with an aggregate containing an others choice
4870 -- and discrete choices we generate the following test:
4872 -- [constraint_error when
4873 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
4880 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Choices_Lo
),
4881 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
)),
4885 Left_Opnd
=> Duplicate_Subexpr
(Choices_Hi
),
4886 Right_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
)));
4889 if Present
(Cond
) then
4891 Make_Raise_Constraint_Error
(Loc
,
4893 Reason
=> CE_Length_Check_Failed
));
4894 -- Questionable reason code, shouldn't that be a
4895 -- CE_Range_Check_Failed ???
4898 -- Now look inside the sub-aggregate to see if there is more work
4900 if Dim
< Aggr_Dimension
then
4902 -- Process positional components
4904 if Present
(Expressions
(Sub_Aggr
)) then
4905 Expr
:= First
(Expressions
(Sub_Aggr
));
4906 while Present
(Expr
) loop
4907 Others_Check
(Expr
, Dim
+ 1);
4912 -- Process component associations
4914 if Present
(Component_Associations
(Sub_Aggr
)) then
4915 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4916 while Present
(Assoc
) loop
4917 Expr
:= Expression
(Assoc
);
4918 Others_Check
(Expr
, Dim
+ 1);
4925 -------------------------
4926 -- Safe_Left_Hand_Side --
4927 -------------------------
4929 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean is
4930 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean;
4931 -- If the left-hand side includes an indexed component, check that
4932 -- the indexes are free of side-effect.
4938 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean is
4940 if Is_Entity_Name
(Indx
) then
4943 elsif Nkind
(Indx
) = N_Integer_Literal
then
4946 elsif Nkind
(Indx
) = N_Function_Call
4947 and then Is_Entity_Name
(Name
(Indx
))
4948 and then Has_Pragma_Pure_Function
(Entity
(Name
(Indx
)))
4952 elsif Nkind
(Indx
) = N_Type_Conversion
4953 and then Is_Safe_Index
(Expression
(Indx
))
4962 -- Start of processing for Safe_Left_Hand_Side
4965 if Is_Entity_Name
(N
) then
4968 elsif Nkind_In
(N
, N_Explicit_Dereference
, N_Selected_Component
)
4969 and then Safe_Left_Hand_Side
(Prefix
(N
))
4973 elsif Nkind
(N
) = N_Indexed_Component
4974 and then Safe_Left_Hand_Side
(Prefix
(N
))
4975 and then Is_Safe_Index
(First
(Expressions
(N
)))
4979 elsif Nkind
(N
) = N_Unchecked_Type_Conversion
then
4980 return Safe_Left_Hand_Side
(Expression
(N
));
4985 end Safe_Left_Hand_Side
;
4990 -- Holds the temporary aggregate value
4993 -- Holds the declaration of Tmp
4995 Aggr_Code
: List_Id
;
4996 Parent_Node
: Node_Id
;
4997 Parent_Kind
: Node_Kind
;
4999 -- Start of processing for Expand_Array_Aggregate
5002 -- Do not touch the special aggregates of attributes used for Asm calls
5004 if Is_RTE
(Ctyp
, RE_Asm_Input_Operand
)
5005 or else Is_RTE
(Ctyp
, RE_Asm_Output_Operand
)
5009 -- Do not expand an aggregate for an array type which contains tasks if
5010 -- the aggregate is associated with an unexpanded return statement of a
5011 -- build-in-place function. The aggregate is expanded when the related
5012 -- return statement (rewritten into an extended return) is processed.
5013 -- This delay ensures that any temporaries and initialization code
5014 -- generated for the aggregate appear in the proper return block and
5015 -- use the correct _chain and _master.
5017 elsif Has_Task
(Base_Type
(Etype
(N
)))
5018 and then Nkind
(Parent
(N
)) = N_Simple_Return_Statement
5019 and then Is_Build_In_Place_Function
5020 (Return_Applies_To
(Return_Statement_Entity
(Parent
(N
))))
5024 -- Do not attempt expansion if error already detected. We may reach this
5025 -- point in spite of previous errors when compiling with -gnatq, to
5026 -- force all possible errors (this is the usual ACATS mode).
5028 elsif Error_Posted
(N
) then
5032 -- If the semantic analyzer has determined that aggregate N will raise
5033 -- Constraint_Error at run time, then the aggregate node has been
5034 -- replaced with an N_Raise_Constraint_Error node and we should
5037 pragma Assert
(not Raises_Constraint_Error
(N
));
5041 -- Check that the index range defined by aggregate bounds is
5042 -- compatible with corresponding index subtype.
5044 Index_Compatibility_Check
: declare
5045 Aggr_Index_Range
: Node_Id
:= First_Index
(Typ
);
5046 -- The current aggregate index range
5048 Index_Constraint
: Node_Id
:= First_Index
(Etype
(Typ
));
5049 -- The corresponding index constraint against which we have to
5050 -- check the above aggregate index range.
5053 Compute_Others_Present
(N
, 1);
5055 for J
in 1 .. Aggr_Dimension
loop
5056 -- There is no need to emit a check if an others choice is present
5057 -- for this array aggregate dimension since in this case one of
5058 -- N's sub-aggregates has taken its bounds from the context and
5059 -- these bounds must have been checked already. In addition all
5060 -- sub-aggregates corresponding to the same dimension must all
5061 -- have the same bounds (checked in (c) below).
5063 if not Range_Checks_Suppressed
(Etype
(Index_Constraint
))
5064 and then not Others_Present
(J
)
5066 -- We don't use Checks.Apply_Range_Check here because it emits
5067 -- a spurious check. Namely it checks that the range defined by
5068 -- the aggregate bounds is non empty. But we know this already
5071 Check_Bounds
(Aggr_Index_Range
, Index_Constraint
);
5074 -- Save the low and high bounds of the aggregate index as well as
5075 -- the index type for later use in checks (b) and (c) below.
5077 Aggr_Low
(J
) := Low_Bound
(Aggr_Index_Range
);
5078 Aggr_High
(J
) := High_Bound
(Aggr_Index_Range
);
5080 Aggr_Index_Typ
(J
) := Etype
(Index_Constraint
);
5082 Next_Index
(Aggr_Index_Range
);
5083 Next_Index
(Index_Constraint
);
5085 end Index_Compatibility_Check
;
5089 -- If an others choice is present check that no aggregate index is
5090 -- outside the bounds of the index constraint.
5092 Others_Check
(N
, 1);
5096 -- For multidimensional arrays make sure that all subaggregates
5097 -- corresponding to the same dimension have the same bounds.
5099 if Aggr_Dimension
> 1 then
5100 Check_Same_Aggr_Bounds
(N
, 1);
5105 -- If we have a default component value, or simple initialization is
5106 -- required for the component type, then we replace <> in component
5107 -- associations by the required default value.
5110 Default_Val
: Node_Id
;
5114 if (Present
(Default_Aspect_Component_Value
(Typ
))
5115 or else Needs_Simple_Initialization
(Ctyp
))
5116 and then Present
(Component_Associations
(N
))
5118 Assoc
:= First
(Component_Associations
(N
));
5119 while Present
(Assoc
) loop
5120 if Nkind
(Assoc
) = N_Component_Association
5121 and then Box_Present
(Assoc
)
5123 Set_Box_Present
(Assoc
, False);
5125 if Present
(Default_Aspect_Component_Value
(Typ
)) then
5126 Default_Val
:= Default_Aspect_Component_Value
(Typ
);
5128 Default_Val
:= Get_Simple_Init_Val
(Ctyp
, N
);
5131 Set_Expression
(Assoc
, New_Copy_Tree
(Default_Val
));
5132 Analyze_And_Resolve
(Expression
(Assoc
), Ctyp
);
5142 -- Here we test for is packed array aggregate that we can handle at
5143 -- compile time. If so, return with transformation done. Note that we do
5144 -- this even if the aggregate is nested, because once we have done this
5145 -- processing, there is no more nested aggregate.
5147 if Packed_Array_Aggregate_Handled
(N
) then
5151 -- At this point we try to convert to positional form
5153 if Ekind
(Current_Scope
) = E_Package
5154 and then Static_Elaboration_Desired
(Current_Scope
)
5156 Convert_To_Positional
(N
, Max_Others_Replicate
=> 100);
5158 Convert_To_Positional
(N
);
5161 -- if the result is no longer an aggregate (e.g. it may be a string
5162 -- literal, or a temporary which has the needed value), then we are
5163 -- done, since there is no longer a nested aggregate.
5165 if Nkind
(N
) /= N_Aggregate
then
5168 -- We are also done if the result is an analyzed aggregate, indicating
5169 -- that Convert_To_Positional succeeded and reanalyzed the rewritten
5172 elsif Analyzed
(N
) and then N
/= Original_Node
(N
) then
5176 -- If all aggregate components are compile-time known and the aggregate
5177 -- has been flattened, nothing left to do. The same occurs if the
5178 -- aggregate is used to initialize the components of a statically
5179 -- allocated dispatch table.
5181 if Compile_Time_Known_Aggregate
(N
)
5182 or else Is_Static_Dispatch_Table_Aggregate
(N
)
5184 Set_Expansion_Delayed
(N
, False);
5188 -- Now see if back end processing is possible
5190 if Backend_Processing_Possible
(N
) then
5192 -- If the aggregate is static but the constraints are not, build
5193 -- a static subtype for the aggregate, so that Gigi can place it
5194 -- in static memory. Perform an unchecked_conversion to the non-
5195 -- static type imposed by the context.
5198 Itype
: constant Entity_Id
:= Etype
(N
);
5200 Needs_Type
: Boolean := False;
5203 Index
:= First_Index
(Itype
);
5204 while Present
(Index
) loop
5205 if not Is_OK_Static_Subtype
(Etype
(Index
)) then
5214 Build_Constrained_Type
(Positional
=> True);
5215 Rewrite
(N
, Unchecked_Convert_To
(Itype
, N
));
5225 -- Delay expansion for nested aggregates: it will be taken care of
5226 -- when the parent aggregate is expanded.
5228 Parent_Node
:= Parent
(N
);
5229 Parent_Kind
:= Nkind
(Parent_Node
);
5231 if Parent_Kind
= N_Qualified_Expression
then
5232 Parent_Node
:= Parent
(Parent_Node
);
5233 Parent_Kind
:= Nkind
(Parent_Node
);
5236 if Parent_Kind
= N_Aggregate
5237 or else Parent_Kind
= N_Extension_Aggregate
5238 or else Parent_Kind
= N_Component_Association
5239 or else (Parent_Kind
= N_Object_Declaration
5240 and then Needs_Finalization
(Typ
))
5241 or else (Parent_Kind
= N_Assignment_Statement
5242 and then Inside_Init_Proc
)
5244 if Static_Array_Aggregate
(N
)
5245 or else Compile_Time_Known_Aggregate
(N
)
5247 Set_Expansion_Delayed
(N
, False);
5250 Set_Expansion_Delayed
(N
);
5257 -- Look if in place aggregate expansion is possible
5259 -- For object declarations we build the aggregate in place, unless
5260 -- the array is bit-packed or the component is controlled.
5262 -- For assignments we do the assignment in place if all the component
5263 -- associations have compile-time known values. For other cases we
5264 -- create a temporary. The analysis for safety of on-line assignment
5265 -- is delicate, i.e. we don't know how to do it fully yet ???
5267 -- For allocators we assign to the designated object in place if the
5268 -- aggregate meets the same conditions as other in-place assignments.
5269 -- In this case the aggregate may not come from source but was created
5270 -- for default initialization, e.g. with Initialize_Scalars.
5272 if Requires_Transient_Scope
(Typ
) then
5273 Establish_Transient_Scope
5274 (N
, Sec_Stack
=> Has_Controlled_Component
(Typ
));
5277 if Has_Default_Init_Comps
(N
) then
5278 Maybe_In_Place_OK
:= False;
5280 elsif Is_Bit_Packed_Array
(Typ
)
5281 or else Has_Controlled_Component
(Typ
)
5283 Maybe_In_Place_OK
:= False;
5286 Maybe_In_Place_OK
:=
5287 (Nkind
(Parent
(N
)) = N_Assignment_Statement
5288 and then In_Place_Assign_OK
)
5291 (Nkind
(Parent
(Parent
(N
))) = N_Allocator
5292 and then In_Place_Assign_OK
);
5295 -- If this is an array of tasks, it will be expanded into build-in-place
5296 -- assignments. Build an activation chain for the tasks now.
5298 if Has_Task
(Etype
(N
)) then
5299 Build_Activation_Chain_Entity
(N
);
5302 -- Perform in-place expansion of aggregate in an object declaration.
5303 -- Note: actions generated for the aggregate will be captured in an
5304 -- expression-with-actions statement so that they can be transferred
5305 -- to freeze actions later if there is an address clause for the
5306 -- object. (Note: we don't use a block statement because this would
5307 -- cause generated freeze nodes to be elaborated in the wrong scope).
5309 -- Should document these individual tests ???
5311 if not Has_Default_Init_Comps
(N
)
5312 and then Comes_From_Source
(Parent_Node
)
5313 and then Parent_Kind
= N_Object_Declaration
5315 Must_Slide
(Etype
(Defining_Identifier
(Parent_Node
)), Typ
)
5316 and then N
= Expression
(Parent_Node
)
5317 and then not Is_Bit_Packed_Array
(Typ
)
5318 and then not Has_Controlled_Component
(Typ
)
5320 In_Place_Assign_OK_For_Declaration
:= True;
5321 Tmp
:= Defining_Identifier
(Parent
(N
));
5322 Set_No_Initialization
(Parent
(N
));
5323 Set_Expression
(Parent
(N
), Empty
);
5325 -- Set kind and type of the entity, for use in the analysis
5326 -- of the subsequent assignments. If the nominal type is not
5327 -- constrained, build a subtype from the known bounds of the
5328 -- aggregate. If the declaration has a subtype mark, use it,
5329 -- otherwise use the itype of the aggregate.
5331 Set_Ekind
(Tmp
, E_Variable
);
5333 if not Is_Constrained
(Typ
) then
5334 Build_Constrained_Type
(Positional
=> False);
5336 elsif Is_Entity_Name
(Object_Definition
(Parent
(N
)))
5337 and then Is_Constrained
(Entity
(Object_Definition
(Parent
(N
))))
5339 Set_Etype
(Tmp
, Entity
(Object_Definition
(Parent
(N
))));
5342 Set_Size_Known_At_Compile_Time
(Typ
, False);
5343 Set_Etype
(Tmp
, Typ
);
5346 elsif Maybe_In_Place_OK
5347 and then Nkind
(Parent
(N
)) = N_Qualified_Expression
5348 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
5350 Set_Expansion_Delayed
(N
);
5353 -- In the remaining cases the aggregate is the RHS of an assignment
5355 elsif Maybe_In_Place_OK
5356 and then Safe_Left_Hand_Side
(Name
(Parent
(N
)))
5358 Tmp
:= Name
(Parent
(N
));
5360 if Etype
(Tmp
) /= Etype
(N
) then
5361 Apply_Length_Check
(N
, Etype
(Tmp
));
5363 if Nkind
(N
) = N_Raise_Constraint_Error
then
5365 -- Static error, nothing further to expand
5371 -- If a slice assignment has an aggregate with a single others_choice,
5372 -- the assignment can be done in place even if bounds are not static,
5373 -- by converting it into a loop over the discrete range of the slice.
5375 elsif Maybe_In_Place_OK
5376 and then Nkind
(Name
(Parent
(N
))) = N_Slice
5377 and then Is_Others_Aggregate
(N
)
5379 Tmp
:= Name
(Parent
(N
));
5381 -- Set type of aggregate to be type of lhs in assignment, in order
5382 -- to suppress redundant length checks.
5384 Set_Etype
(N
, Etype
(Tmp
));
5388 -- In place aggregate expansion is not possible
5391 Maybe_In_Place_OK
:= False;
5392 Tmp
:= Make_Temporary
(Loc
, 'A', N
);
5394 Make_Object_Declaration
(Loc
,
5395 Defining_Identifier
=> Tmp
,
5396 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
5397 Set_No_Initialization
(Tmp_Decl
, True);
5399 -- If we are within a loop, the temporary will be pushed on the
5400 -- stack at each iteration. If the aggregate is the expression for an
5401 -- allocator, it will be immediately copied to the heap and can
5402 -- be reclaimed at once. We create a transient scope around the
5403 -- aggregate for this purpose.
5405 if Ekind
(Current_Scope
) = E_Loop
5406 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
5408 Establish_Transient_Scope
(N
, False);
5411 Insert_Action
(N
, Tmp_Decl
);
5414 -- Construct and insert the aggregate code. We can safely suppress index
5415 -- checks because this code is guaranteed not to raise CE on index
5416 -- checks. However we should *not* suppress all checks.
5422 if Nkind
(Tmp
) = N_Defining_Identifier
then
5423 Target
:= New_Occurrence_Of
(Tmp
, Loc
);
5426 if Has_Default_Init_Comps
(N
) then
5428 -- Ada 2005 (AI-287): This case has not been analyzed???
5430 raise Program_Error
;
5433 -- Name in assignment is explicit dereference
5435 Target
:= New_Copy
(Tmp
);
5438 -- If we are to generate an in place assignment for a declaration or
5439 -- an assignment statement, and the assignment can be done directly
5440 -- by the back end, then do not expand further.
5442 -- ??? We can also do that if in place expansion is not possible but
5443 -- then we could go into an infinite recursion.
5445 if (In_Place_Assign_OK_For_Declaration
or else Maybe_In_Place_OK
)
5446 and then VM_Target
= No_VM
5447 and then not AAMP_On_Target
5448 and then not Generate_SCIL
5449 and then not Possible_Bit_Aligned_Component
(Target
)
5450 and then not Is_Possibly_Unaligned_Slice
(Target
)
5451 and then Aggr_Assignment_OK_For_Backend
(N
)
5453 if Maybe_In_Place_OK
then
5459 Make_Assignment_Statement
(Loc
,
5461 Expression
=> New_Copy
(N
)));
5465 Build_Array_Aggr_Code
(N
,
5467 Index
=> First_Index
(Typ
),
5469 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
5472 -- Save the last assignment statement associated with the aggregate
5473 -- when building a controlled object. This reference is utilized by
5474 -- the finalization machinery when marking an object as successfully
5477 if Needs_Finalization
(Typ
)
5478 and then Is_Entity_Name
(Target
)
5479 and then Present
(Entity
(Target
))
5480 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
5482 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
5486 -- If the aggregate is the expression in a declaration, the expanded
5487 -- code must be inserted after it. The defining entity might not come
5488 -- from source if this is part of an inlined body, but the declaration
5491 if Comes_From_Source
(Tmp
)
5493 (Nkind
(Parent
(N
)) = N_Object_Declaration
5494 and then Comes_From_Source
(Parent
(N
))
5495 and then Tmp
= Defining_Entity
(Parent
(N
)))
5498 Node_After
: constant Node_Id
:= Next
(Parent_Node
);
5501 Insert_Actions_After
(Parent_Node
, Aggr_Code
);
5503 if Parent_Kind
= N_Object_Declaration
then
5504 Collect_Initialization_Statements
5505 (Obj
=> Tmp
, N
=> Parent_Node
, Node_After
=> Node_After
);
5510 Insert_Actions
(N
, Aggr_Code
);
5513 -- If the aggregate has been assigned in place, remove the original
5516 if Nkind
(Parent
(N
)) = N_Assignment_Statement
5517 and then Maybe_In_Place_OK
5519 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
5521 elsif Nkind
(Parent
(N
)) /= N_Object_Declaration
5522 or else Tmp
/= Defining_Identifier
(Parent
(N
))
5524 Rewrite
(N
, New_Occurrence_Of
(Tmp
, Loc
));
5525 Analyze_And_Resolve
(N
, Typ
);
5527 end Expand_Array_Aggregate
;
5529 ------------------------
5530 -- Expand_N_Aggregate --
5531 ------------------------
5533 procedure Expand_N_Aggregate
(N
: Node_Id
) is
5535 -- Record aggregate case
5537 if Is_Record_Type
(Etype
(N
)) then
5538 Expand_Record_Aggregate
(N
);
5540 -- Array aggregate case
5543 -- A special case, if we have a string subtype with bounds 1 .. N,
5544 -- where N is known at compile time, and the aggregate is of the
5545 -- form (others => 'x'), with a single choice and no expressions,
5546 -- and N is less than 80 (an arbitrary limit for now), then replace
5547 -- the aggregate by the equivalent string literal (but do not mark
5548 -- it as static since it is not).
5550 -- Note: this entire circuit is redundant with respect to code in
5551 -- Expand_Array_Aggregate that collapses others choices to positional
5552 -- form, but there are two problems with that circuit:
5554 -- a) It is limited to very small cases due to ill-understood
5555 -- interactions with bootstrapping. That limit is removed by
5556 -- use of the No_Implicit_Loops restriction.
5558 -- b) It incorrectly ends up with the resulting expressions being
5559 -- considered static when they are not. For example, the
5560 -- following test should fail:
5562 -- pragma Restrictions (No_Implicit_Loops);
5563 -- package NonSOthers4 is
5564 -- B : constant String (1 .. 6) := (others => 'A');
5565 -- DH : constant String (1 .. 8) := B & "BB";
5567 -- pragma Export (C, X, Link_Name => DH);
5570 -- But it succeeds (DH looks static to pragma Export)
5572 -- To be sorted out ???
5574 if Present
(Component_Associations
(N
)) then
5576 CA
: constant Node_Id
:= First
(Component_Associations
(N
));
5577 MX
: constant := 80;
5580 if Nkind
(First
(Choices
(CA
))) = N_Others_Choice
5581 and then Nkind
(Expression
(CA
)) = N_Character_Literal
5582 and then No
(Expressions
(N
))
5585 T
: constant Entity_Id
:= Etype
(N
);
5586 X
: constant Node_Id
:= First_Index
(T
);
5587 EC
: constant Node_Id
:= Expression
(CA
);
5588 CV
: constant Uint
:= Char_Literal_Value
(EC
);
5589 CC
: constant Int
:= UI_To_Int
(CV
);
5592 if Nkind
(X
) = N_Range
5593 and then Compile_Time_Known_Value
(Low_Bound
(X
))
5594 and then Expr_Value
(Low_Bound
(X
)) = 1
5595 and then Compile_Time_Known_Value
(High_Bound
(X
))
5598 Hi
: constant Uint
:= Expr_Value
(High_Bound
(X
));
5604 for J
in 1 .. UI_To_Int
(Hi
) loop
5605 Store_String_Char
(Char_Code
(CC
));
5609 Make_String_Literal
(Sloc
(N
),
5610 Strval
=> End_String
));
5612 if CC
>= Int
(2 ** 16) then
5613 Set_Has_Wide_Wide_Character
(N
);
5614 elsif CC
>= Int
(2 ** 8) then
5615 Set_Has_Wide_Character
(N
);
5618 Analyze_And_Resolve
(N
, T
);
5619 Set_Is_Static_Expression
(N
, False);
5629 -- Not that special case, so normal expansion of array aggregate
5631 Expand_Array_Aggregate
(N
);
5635 when RE_Not_Available
=>
5637 end Expand_N_Aggregate
;
5639 ----------------------------------
5640 -- Expand_N_Extension_Aggregate --
5641 ----------------------------------
5643 -- If the ancestor part is an expression, add a component association for
5644 -- the parent field. If the type of the ancestor part is not the direct
5645 -- parent of the expected type, build recursively the needed ancestors.
5646 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
5647 -- ration for a temporary of the expected type, followed by individual
5648 -- assignments to the given components.
5650 procedure Expand_N_Extension_Aggregate
(N
: Node_Id
) is
5651 Loc
: constant Source_Ptr
:= Sloc
(N
);
5652 A
: constant Node_Id
:= Ancestor_Part
(N
);
5653 Typ
: constant Entity_Id
:= Etype
(N
);
5656 -- If the ancestor is a subtype mark, an init proc must be called
5657 -- on the resulting object which thus has to be materialized in
5660 if Is_Entity_Name
(A
) and then Is_Type
(Entity
(A
)) then
5661 Convert_To_Assignments
(N
, Typ
);
5663 -- The extension aggregate is transformed into a record aggregate
5664 -- of the following form (c1 and c2 are inherited components)
5666 -- (Exp with c3 => a, c4 => b)
5667 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c3 => a, c4 => b)
5672 if Tagged_Type_Expansion
then
5673 Expand_Record_Aggregate
(N
,
5676 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
),
5679 -- No tag is needed in the case of a VM
5682 Expand_Record_Aggregate
(N
, Parent_Expr
=> A
);
5687 when RE_Not_Available
=>
5689 end Expand_N_Extension_Aggregate
;
5691 -----------------------------
5692 -- Expand_Record_Aggregate --
5693 -----------------------------
5695 procedure Expand_Record_Aggregate
5697 Orig_Tag
: Node_Id
:= Empty
;
5698 Parent_Expr
: Node_Id
:= Empty
)
5700 Loc
: constant Source_Ptr
:= Sloc
(N
);
5701 Comps
: constant List_Id
:= Component_Associations
(N
);
5702 Typ
: constant Entity_Id
:= Etype
(N
);
5703 Base_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
5705 Static_Components
: Boolean := True;
5706 -- Flag to indicate whether all components are compile-time known,
5707 -- and the aggregate can be constructed statically and handled by
5710 function Compile_Time_Known_Composite_Value
(N
: Node_Id
) return Boolean;
5711 -- Returns true if N is an expression of composite type which can be
5712 -- fully evaluated at compile time without raising constraint error.
5713 -- Such expressions can be passed as is to Gigi without any expansion.
5715 -- This returns true for N_Aggregate with Compile_Time_Known_Aggregate
5716 -- set and constants whose expression is such an aggregate, recursively.
5718 function Component_Not_OK_For_Backend
return Boolean;
5719 -- Check for presence of a component which makes it impossible for the
5720 -- backend to process the aggregate, thus requiring the use of a series
5721 -- of assignment statements. Cases checked for are a nested aggregate
5722 -- needing Late_Expansion, the presence of a tagged component which may
5723 -- need tag adjustment, and a bit unaligned component reference.
5725 -- We also force expansion into assignments if a component is of a
5726 -- mutable type (including a private type with discriminants) because
5727 -- in that case the size of the component to be copied may be smaller
5728 -- than the side of the target, and there is no simple way for gigi
5729 -- to compute the size of the object to be copied.
5731 -- NOTE: This is part of the ongoing work to define precisely the
5732 -- interface between front-end and back-end handling of aggregates.
5733 -- In general it is desirable to pass aggregates as they are to gigi,
5734 -- in order to minimize elaboration code. This is one case where the
5735 -- semantics of Ada complicate the analysis and lead to anomalies in
5736 -- the gcc back-end if the aggregate is not expanded into assignments.
5738 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean;
5739 -- If any ancestor of the current type is private, the aggregate
5740 -- cannot be built in place. We cannot rely on Has_Private_Ancestor,
5741 -- because it will not be set when type and its parent are in the
5742 -- same scope, and the parent component needs expansion.
5744 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
;
5745 -- For nested aggregates return the ultimate enclosing aggregate; for
5746 -- non-nested aggregates return N.
5748 ----------------------------------------
5749 -- Compile_Time_Known_Composite_Value --
5750 ----------------------------------------
5752 function Compile_Time_Known_Composite_Value
5753 (N
: Node_Id
) return Boolean
5756 -- If we have an entity name, then see if it is the name of a
5757 -- constant and if so, test the corresponding constant value.
5759 if Is_Entity_Name
(N
) then
5761 E
: constant Entity_Id
:= Entity
(N
);
5764 if Ekind
(E
) /= E_Constant
then
5767 V
:= Constant_Value
(E
);
5769 and then Compile_Time_Known_Composite_Value
(V
);
5773 -- We have a value, see if it is compile time known
5776 if Nkind
(N
) = N_Aggregate
then
5777 return Compile_Time_Known_Aggregate
(N
);
5780 -- All other types of values are not known at compile time
5785 end Compile_Time_Known_Composite_Value
;
5787 ----------------------------------
5788 -- Component_Not_OK_For_Backend --
5789 ----------------------------------
5791 function Component_Not_OK_For_Backend
return Boolean is
5801 while Present
(C
) loop
5803 -- If the component has box initialization, expansion is needed
5804 -- and component is not ready for backend.
5806 if Box_Present
(C
) then
5810 if Nkind
(Expression
(C
)) = N_Qualified_Expression
then
5811 Expr_Q
:= Expression
(Expression
(C
));
5813 Expr_Q
:= Expression
(C
);
5816 -- Return true if the aggregate has any associations for tagged
5817 -- components that may require tag adjustment.
5819 -- These are cases where the source expression may have a tag that
5820 -- could differ from the component tag (e.g., can occur for type
5821 -- conversions and formal parameters). (Tag adjustment not needed
5822 -- if VM_Target because object tags are implicit in the machine.)
5824 if Is_Tagged_Type
(Etype
(Expr_Q
))
5825 and then (Nkind
(Expr_Q
) = N_Type_Conversion
5826 or else (Is_Entity_Name
(Expr_Q
)
5828 Ekind
(Entity
(Expr_Q
)) in Formal_Kind
))
5829 and then Tagged_Type_Expansion
5831 Static_Components
:= False;
5834 elsif Is_Delayed_Aggregate
(Expr_Q
) then
5835 Static_Components
:= False;
5838 elsif Possible_Bit_Aligned_Component
(Expr_Q
) then
5839 Static_Components
:= False;
5843 if Is_Elementary_Type
(Etype
(Expr_Q
)) then
5844 if not Compile_Time_Known_Value
(Expr_Q
) then
5845 Static_Components
:= False;
5848 elsif not Compile_Time_Known_Composite_Value
(Expr_Q
) then
5849 Static_Components
:= False;
5851 if Is_Private_Type
(Etype
(Expr_Q
))
5852 and then Has_Discriminants
(Etype
(Expr_Q
))
5862 end Component_Not_OK_For_Backend
;
5864 -----------------------------------
5865 -- Has_Visible_Private_Ancestor --
5866 -----------------------------------
5868 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean is
5869 R
: constant Entity_Id
:= Root_Type
(Id
);
5870 T1
: Entity_Id
:= Id
;
5874 if Is_Private_Type
(T1
) then
5884 end Has_Visible_Private_Ancestor
;
5886 -------------------------
5887 -- Top_Level_Aggregate --
5888 -------------------------
5890 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
is
5895 while Present
(Parent
(Aggr
))
5896 and then Nkind_In
(Parent
(Aggr
), N_Component_Association
,
5899 Aggr
:= Parent
(Aggr
);
5903 end Top_Level_Aggregate
;
5907 Top_Level_Aggr
: constant Node_Id
:= Top_Level_Aggregate
(N
);
5908 Tag_Value
: Node_Id
;
5912 -- Start of processing for Expand_Record_Aggregate
5915 -- If the aggregate is to be assigned to an atomic variable, we have
5916 -- to prevent a piecemeal assignment even if the aggregate is to be
5917 -- expanded. We create a temporary for the aggregate, and assign the
5918 -- temporary instead, so that the back end can generate an atomic move
5922 and then Comes_From_Source
(Parent
(N
))
5923 and then Is_Atomic_Aggregate
(N
, Typ
)
5927 -- No special management required for aggregates used to initialize
5928 -- statically allocated dispatch tables
5930 elsif Is_Static_Dispatch_Table_Aggregate
(N
) then
5934 -- Ada 2005 (AI-318-2): We need to convert to assignments if components
5935 -- are build-in-place function calls. The assignments will each turn
5936 -- into a build-in-place function call. If components are all static,
5937 -- we can pass the aggregate to the backend regardless of limitedness.
5939 -- Extension aggregates, aggregates in extended return statements, and
5940 -- aggregates for C++ imported types must be expanded.
5942 if Ada_Version
>= Ada_2005
and then Is_Limited_View
(Typ
) then
5943 if not Nkind_In
(Parent
(N
), N_Object_Declaration
,
5944 N_Component_Association
)
5946 Convert_To_Assignments
(N
, Typ
);
5948 elsif Nkind
(N
) = N_Extension_Aggregate
5949 or else Convention
(Typ
) = Convention_CPP
5951 Convert_To_Assignments
(N
, Typ
);
5953 elsif not Size_Known_At_Compile_Time
(Typ
)
5954 or else Component_Not_OK_For_Backend
5955 or else not Static_Components
5957 Convert_To_Assignments
(N
, Typ
);
5960 Set_Compile_Time_Known_Aggregate
(N
);
5961 Set_Expansion_Delayed
(N
, False);
5964 -- Gigi doesn't properly handle temporaries of variable size so we
5965 -- generate it in the front-end
5967 elsif not Size_Known_At_Compile_Time
(Typ
)
5968 and then Tagged_Type_Expansion
5970 Convert_To_Assignments
(N
, Typ
);
5972 -- An aggregate used to initialize a controlled object must be turned
5973 -- into component assignments as the components themselves may require
5974 -- finalization actions such as adjustment.
5976 elsif Needs_Finalization
(Typ
) then
5977 Convert_To_Assignments
(N
, Typ
);
5979 -- Ada 2005 (AI-287): In case of default initialized components we
5980 -- convert the aggregate into assignments.
5982 elsif Has_Default_Init_Comps
(N
) then
5983 Convert_To_Assignments
(N
, Typ
);
5987 elsif Component_Not_OK_For_Backend
then
5988 Convert_To_Assignments
(N
, Typ
);
5990 -- If an ancestor is private, some components are not inherited and we
5991 -- cannot expand into a record aggregate.
5993 elsif Has_Visible_Private_Ancestor
(Typ
) then
5994 Convert_To_Assignments
(N
, Typ
);
5996 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
5997 -- is not able to handle the aggregate for Late_Request.
5999 elsif Is_Tagged_Type
(Typ
) and then Has_Discriminants
(Typ
) then
6000 Convert_To_Assignments
(N
, Typ
);
6002 -- If the tagged types covers interface types we need to initialize all
6003 -- hidden components containing pointers to secondary dispatch tables.
6005 elsif Is_Tagged_Type
(Typ
) and then Has_Interfaces
(Typ
) then
6006 Convert_To_Assignments
(N
, Typ
);
6008 -- If some components are mutable, the size of the aggregate component
6009 -- may be distinct from the default size of the type component, so
6010 -- we need to expand to insure that the back-end copies the proper
6011 -- size of the data. However, if the aggregate is the initial value of
6012 -- a constant, the target is immutable and might be built statically
6013 -- if components are appropriate.
6015 elsif Has_Mutable_Components
(Typ
)
6017 (Nkind
(Parent
(Top_Level_Aggr
)) /= N_Object_Declaration
6018 or else not Constant_Present
(Parent
(Top_Level_Aggr
))
6019 or else not Static_Components
)
6021 Convert_To_Assignments
(N
, Typ
);
6023 -- If the type involved has bit aligned components, then we are not sure
6024 -- that the back end can handle this case correctly.
6026 elsif Type_May_Have_Bit_Aligned_Components
(Typ
) then
6027 Convert_To_Assignments
(N
, Typ
);
6029 -- In all other cases, build a proper aggregate to be handled by gigi
6032 if Nkind
(N
) = N_Aggregate
then
6034 -- If the aggregate is static and can be handled by the back-end,
6035 -- nothing left to do.
6037 if Static_Components
then
6038 Set_Compile_Time_Known_Aggregate
(N
);
6039 Set_Expansion_Delayed
(N
, False);
6043 -- If no discriminants, nothing special to do
6045 if not Has_Discriminants
(Typ
) then
6048 -- Case of discriminants present
6050 elsif Is_Derived_Type
(Typ
) then
6052 -- For untagged types, non-stored discriminants are replaced
6053 -- with stored discriminants, which are the ones that gigi uses
6054 -- to describe the type and its components.
6056 Generate_Aggregate_For_Derived_Type
: declare
6057 Constraints
: constant List_Id
:= New_List
;
6058 First_Comp
: Node_Id
;
6059 Discriminant
: Entity_Id
;
6061 Num_Disc
: Int
:= 0;
6062 Num_Gird
: Int
:= 0;
6064 procedure Prepend_Stored_Values
(T
: Entity_Id
);
6065 -- Scan the list of stored discriminants of the type, and add
6066 -- their values to the aggregate being built.
6068 ---------------------------
6069 -- Prepend_Stored_Values --
6070 ---------------------------
6072 procedure Prepend_Stored_Values
(T
: Entity_Id
) is
6074 Discriminant
:= First_Stored_Discriminant
(T
);
6075 while Present
(Discriminant
) loop
6077 Make_Component_Association
(Loc
,
6079 New_List
(New_Occurrence_Of
(Discriminant
, Loc
)),
6083 (Get_Discriminant_Value
6086 Discriminant_Constraint
(Typ
))));
6088 if No
(First_Comp
) then
6089 Prepend_To
(Component_Associations
(N
), New_Comp
);
6091 Insert_After
(First_Comp
, New_Comp
);
6094 First_Comp
:= New_Comp
;
6095 Next_Stored_Discriminant
(Discriminant
);
6097 end Prepend_Stored_Values
;
6099 -- Start of processing for Generate_Aggregate_For_Derived_Type
6102 -- Remove the associations for the discriminant of derived type
6104 First_Comp
:= First
(Component_Associations
(N
));
6105 while Present
(First_Comp
) loop
6109 if Ekind
(Entity
(First
(Choices
(Comp
)))) = E_Discriminant
6112 Num_Disc
:= Num_Disc
+ 1;
6116 -- Insert stored discriminant associations in the correct
6117 -- order. If there are more stored discriminants than new
6118 -- discriminants, there is at least one new discriminant that
6119 -- constrains more than one of the stored discriminants. In
6120 -- this case we need to construct a proper subtype of the
6121 -- parent type, in order to supply values to all the
6122 -- components. Otherwise there is one-one correspondence
6123 -- between the constraints and the stored discriminants.
6125 First_Comp
:= Empty
;
6127 Discriminant
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6128 while Present
(Discriminant
) loop
6129 Num_Gird
:= Num_Gird
+ 1;
6130 Next_Stored_Discriminant
(Discriminant
);
6133 -- Case of more stored discriminants than new discriminants
6135 if Num_Gird
> Num_Disc
then
6137 -- Create a proper subtype of the parent type, which is the
6138 -- proper implementation type for the aggregate, and convert
6139 -- it to the intended target type.
6141 Discriminant
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6142 while Present
(Discriminant
) loop
6145 (Get_Discriminant_Value
6148 Discriminant_Constraint
(Typ
)));
6149 Append
(New_Comp
, Constraints
);
6150 Next_Stored_Discriminant
(Discriminant
);
6154 Make_Subtype_Declaration
(Loc
,
6155 Defining_Identifier
=> Make_Temporary
(Loc
, 'T'),
6156 Subtype_Indication
=>
6157 Make_Subtype_Indication
(Loc
,
6159 New_Occurrence_Of
(Etype
(Base_Type
(Typ
)), Loc
),
6161 Make_Index_Or_Discriminant_Constraint
6162 (Loc
, Constraints
)));
6164 Insert_Action
(N
, Decl
);
6165 Prepend_Stored_Values
(Base_Type
(Typ
));
6167 Set_Etype
(N
, Defining_Identifier
(Decl
));
6170 Rewrite
(N
, Unchecked_Convert_To
(Typ
, N
));
6173 -- Case where we do not have fewer new discriminants than
6174 -- stored discriminants, so in this case we can simply use the
6175 -- stored discriminants of the subtype.
6178 Prepend_Stored_Values
(Typ
);
6180 end Generate_Aggregate_For_Derived_Type
;
6183 if Is_Tagged_Type
(Typ
) then
6185 -- In the tagged case, _parent and _tag component must be created
6187 -- Reset Null_Present unconditionally. Tagged records always have
6188 -- at least one field (the tag or the parent).
6190 Set_Null_Record_Present
(N
, False);
6192 -- When the current aggregate comes from the expansion of an
6193 -- extension aggregate, the parent expr is replaced by an
6194 -- aggregate formed by selected components of this expr.
6196 if Present
(Parent_Expr
) and then Is_Empty_List
(Comps
) then
6197 Comp
:= First_Component_Or_Discriminant
(Typ
);
6198 while Present
(Comp
) loop
6200 -- Skip all expander-generated components
6202 if not Comes_From_Source
(Original_Record_Component
(Comp
))
6208 Make_Selected_Component
(Loc
,
6210 Unchecked_Convert_To
(Typ
,
6211 Duplicate_Subexpr
(Parent_Expr
, True)),
6212 Selector_Name
=> New_Occurrence_Of
(Comp
, Loc
));
6215 Make_Component_Association
(Loc
,
6217 New_List
(New_Occurrence_Of
(Comp
, Loc
)),
6218 Expression
=> New_Comp
));
6220 Analyze_And_Resolve
(New_Comp
, Etype
(Comp
));
6223 Next_Component_Or_Discriminant
(Comp
);
6227 -- Compute the value for the Tag now, if the type is a root it
6228 -- will be included in the aggregate right away, otherwise it will
6229 -- be propagated to the parent aggregate.
6231 if Present
(Orig_Tag
) then
6232 Tag_Value
:= Orig_Tag
;
6233 elsif not Tagged_Type_Expansion
then
6238 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
);
6241 -- For a derived type, an aggregate for the parent is formed with
6242 -- all the inherited components.
6244 if Is_Derived_Type
(Typ
) then
6247 First_Comp
: Node_Id
;
6248 Parent_Comps
: List_Id
;
6249 Parent_Aggr
: Node_Id
;
6250 Parent_Name
: Node_Id
;
6253 -- Remove the inherited component association from the
6254 -- aggregate and store them in the parent aggregate
6256 First_Comp
:= First
(Component_Associations
(N
));
6257 Parent_Comps
:= New_List
;
6258 while Present
(First_Comp
)
6260 Scope
(Original_Record_Component
6261 (Entity
(First
(Choices
(First_Comp
))))) /=
6267 Append
(Comp
, Parent_Comps
);
6271 Make_Aggregate
(Loc
,
6272 Component_Associations
=> Parent_Comps
);
6273 Set_Etype
(Parent_Aggr
, Etype
(Base_Type
(Typ
)));
6275 -- Find the _parent component
6277 Comp
:= First_Component
(Typ
);
6278 while Chars
(Comp
) /= Name_uParent
loop
6279 Comp
:= Next_Component
(Comp
);
6282 Parent_Name
:= New_Occurrence_Of
(Comp
, Loc
);
6284 -- Insert the parent aggregate
6286 Prepend_To
(Component_Associations
(N
),
6287 Make_Component_Association
(Loc
,
6288 Choices
=> New_List
(Parent_Name
),
6289 Expression
=> Parent_Aggr
));
6291 -- Expand recursively the parent propagating the right Tag
6293 Expand_Record_Aggregate
6294 (Parent_Aggr
, Tag_Value
, Parent_Expr
);
6296 -- The ancestor part may be a nested aggregate that has
6297 -- delayed expansion: recheck now.
6299 if Component_Not_OK_For_Backend
then
6300 Convert_To_Assignments
(N
, Typ
);
6304 -- For a root type, the tag component is added (unless compiling
6305 -- for the VMs, where tags are implicit).
6307 elsif Tagged_Type_Expansion
then
6309 Tag_Name
: constant Node_Id
:=
6310 New_Occurrence_Of
(First_Tag_Component
(Typ
), Loc
);
6311 Typ_Tag
: constant Entity_Id
:= RTE
(RE_Tag
);
6312 Conv_Node
: constant Node_Id
:=
6313 Unchecked_Convert_To
(Typ_Tag
, Tag_Value
);
6316 Set_Etype
(Conv_Node
, Typ_Tag
);
6317 Prepend_To
(Component_Associations
(N
),
6318 Make_Component_Association
(Loc
,
6319 Choices
=> New_List
(Tag_Name
),
6320 Expression
=> Conv_Node
));
6326 end Expand_Record_Aggregate
;
6328 ----------------------------
6329 -- Has_Default_Init_Comps --
6330 ----------------------------
6332 function Has_Default_Init_Comps
(N
: Node_Id
) return Boolean is
6333 Comps
: constant List_Id
:= Component_Associations
(N
);
6338 pragma Assert
(Nkind_In
(N
, N_Aggregate
, N_Extension_Aggregate
));
6344 if Has_Self_Reference
(N
) then
6348 -- Check if any direct component has default initialized components
6351 while Present
(C
) loop
6352 if Box_Present
(C
) then
6359 -- Recursive call in case of aggregate expression
6362 while Present
(C
) loop
6363 Expr
:= Expression
(C
);
6366 and then Nkind_In
(Expr
, N_Aggregate
, N_Extension_Aggregate
)
6367 and then Has_Default_Init_Comps
(Expr
)
6376 end Has_Default_Init_Comps
;
6378 --------------------------
6379 -- Is_Delayed_Aggregate --
6380 --------------------------
6382 function Is_Delayed_Aggregate
(N
: Node_Id
) return Boolean is
6383 Node
: Node_Id
:= N
;
6384 Kind
: Node_Kind
:= Nkind
(Node
);
6387 if Kind
= N_Qualified_Expression
then
6388 Node
:= Expression
(Node
);
6389 Kind
:= Nkind
(Node
);
6392 if not Nkind_In
(Kind
, N_Aggregate
, N_Extension_Aggregate
) then
6395 return Expansion_Delayed
(Node
);
6397 end Is_Delayed_Aggregate
;
6399 ----------------------------------------
6400 -- Is_Static_Dispatch_Table_Aggregate --
6401 ----------------------------------------
6403 function Is_Static_Dispatch_Table_Aggregate
(N
: Node_Id
) return Boolean is
6404 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
6407 return Static_Dispatch_Tables
6408 and then Tagged_Type_Expansion
6409 and then RTU_Loaded
(Ada_Tags
)
6411 -- Avoid circularity when rebuilding the compiler
6413 and then Cunit_Entity
(Get_Source_Unit
(N
)) /= RTU_Entity
(Ada_Tags
)
6414 and then (Typ
= RTE
(RE_Dispatch_Table_Wrapper
)
6416 Typ
= RTE
(RE_Address_Array
)
6418 Typ
= RTE
(RE_Type_Specific_Data
)
6420 Typ
= RTE
(RE_Tag_Table
)
6422 (RTE_Available
(RE_Interface_Data
)
6423 and then Typ
= RTE
(RE_Interface_Data
))
6425 (RTE_Available
(RE_Interfaces_Array
)
6426 and then Typ
= RTE
(RE_Interfaces_Array
))
6428 (RTE_Available
(RE_Interface_Data_Element
)
6429 and then Typ
= RTE
(RE_Interface_Data_Element
)));
6430 end Is_Static_Dispatch_Table_Aggregate
;
6432 -----------------------------
6433 -- Is_Two_Dim_Packed_Array --
6434 -----------------------------
6436 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean is
6437 C
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
6439 return Number_Dimensions
(Typ
) = 2
6440 and then Is_Bit_Packed_Array
(Typ
)
6441 and then (C
= 1 or else C
= 2 or else C
= 4);
6442 end Is_Two_Dim_Packed_Array
;
6444 --------------------
6445 -- Late_Expansion --
6446 --------------------
6448 function Late_Expansion
6451 Target
: Node_Id
) return List_Id
6453 Aggr_Code
: List_Id
;
6456 if Is_Record_Type
(Etype
(N
)) then
6457 Aggr_Code
:= Build_Record_Aggr_Code
(N
, Typ
, Target
);
6459 else pragma Assert
(Is_Array_Type
(Etype
(N
)));
6461 Build_Array_Aggr_Code
6463 Ctype
=> Component_Type
(Etype
(N
)),
6464 Index
=> First_Index
(Typ
),
6466 Scalar_Comp
=> Is_Scalar_Type
(Component_Type
(Typ
)),
6467 Indexes
=> No_List
);
6470 -- Save the last assignment statement associated with the aggregate
6471 -- when building a controlled object. This reference is utilized by
6472 -- the finalization machinery when marking an object as successfully
6475 if Needs_Finalization
(Typ
)
6476 and then Is_Entity_Name
(Target
)
6477 and then Present
(Entity
(Target
))
6478 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
6480 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
6486 ----------------------------------
6487 -- Make_OK_Assignment_Statement --
6488 ----------------------------------
6490 function Make_OK_Assignment_Statement
6493 Expression
: Node_Id
) return Node_Id
6496 Set_Assignment_OK
(Name
);
6497 return Make_Assignment_Statement
(Sloc
, Name
, Expression
);
6498 end Make_OK_Assignment_Statement
;
6500 -----------------------
6501 -- Number_Of_Choices --
6502 -----------------------
6504 function Number_Of_Choices
(N
: Node_Id
) return Nat
is
6508 Nb_Choices
: Nat
:= 0;
6511 if Present
(Expressions
(N
)) then
6515 Assoc
:= First
(Component_Associations
(N
));
6516 while Present
(Assoc
) loop
6517 Choice
:= First
(Choices
(Assoc
));
6518 while Present
(Choice
) loop
6519 if Nkind
(Choice
) /= N_Others_Choice
then
6520 Nb_Choices
:= Nb_Choices
+ 1;
6530 end Number_Of_Choices
;
6532 ------------------------------------
6533 -- Packed_Array_Aggregate_Handled --
6534 ------------------------------------
6536 -- The current version of this procedure will handle at compile time
6537 -- any array aggregate that meets these conditions:
6539 -- One and two dimensional, bit packed
6540 -- Underlying packed type is modular type
6541 -- Bounds are within 32-bit Int range
6542 -- All bounds and values are static
6544 -- Note: for now, in the 2-D case, we only handle component sizes of
6545 -- 1, 2, 4 (cases where an integral number of elements occupies a byte).
6547 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean is
6548 Loc
: constant Source_Ptr
:= Sloc
(N
);
6549 Typ
: constant Entity_Id
:= Etype
(N
);
6550 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
6552 Not_Handled
: exception;
6553 -- Exception raised if this aggregate cannot be handled
6556 -- Handle one- or two dimensional bit packed array
6558 if not Is_Bit_Packed_Array
(Typ
)
6559 or else Number_Dimensions
(Typ
) > 2
6564 -- If two-dimensional, check whether it can be folded, and transformed
6565 -- into a one-dimensional aggregate for the Packed_Array_Impl_Type of
6566 -- the original type.
6568 if Number_Dimensions
(Typ
) = 2 then
6569 return Two_Dim_Packed_Array_Handled
(N
);
6572 if not Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
)) then
6576 if not Is_Scalar_Type
(Component_Type
(Typ
))
6577 and then Has_Non_Standard_Rep
(Component_Type
(Typ
))
6583 Csiz
: constant Nat
:= UI_To_Int
(Component_Size
(Typ
));
6587 -- Bounds of index type
6591 -- Values of bounds if compile time known
6593 function Get_Component_Val
(N
: Node_Id
) return Uint
;
6594 -- Given a expression value N of the component type Ctyp, returns a
6595 -- value of Csiz (component size) bits representing this value. If
6596 -- the value is non-static or any other reason exists why the value
6597 -- cannot be returned, then Not_Handled is raised.
6599 -----------------------
6600 -- Get_Component_Val --
6601 -----------------------
6603 function Get_Component_Val
(N
: Node_Id
) return Uint
is
6607 -- We have to analyze the expression here before doing any further
6608 -- processing here. The analysis of such expressions is deferred
6609 -- till expansion to prevent some problems of premature analysis.
6611 Analyze_And_Resolve
(N
, Ctyp
);
6613 -- Must have a compile time value. String literals have to be
6614 -- converted into temporaries as well, because they cannot easily
6615 -- be converted into their bit representation.
6617 if not Compile_Time_Known_Value
(N
)
6618 or else Nkind
(N
) = N_String_Literal
6623 Val
:= Expr_Rep_Value
(N
);
6625 -- Adjust for bias, and strip proper number of bits
6627 if Has_Biased_Representation
(Ctyp
) then
6628 Val
:= Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
6631 return Val
mod Uint_2
** Csiz
;
6632 end Get_Component_Val
;
6634 -- Here we know we have a one dimensional bit packed array
6637 Get_Index_Bounds
(First_Index
(Typ
), Lo
, Hi
);
6639 -- Cannot do anything if bounds are dynamic
6641 if not Compile_Time_Known_Value
(Lo
)
6643 not Compile_Time_Known_Value
(Hi
)
6648 -- Or are silly out of range of int bounds
6650 Lob
:= Expr_Value
(Lo
);
6651 Hib
:= Expr_Value
(Hi
);
6653 if not UI_Is_In_Int_Range
(Lob
)
6655 not UI_Is_In_Int_Range
(Hib
)
6660 -- At this stage we have a suitable aggregate for handling at compile
6661 -- time. The only remaining checks are that the values of expressions
6662 -- in the aggregate are compile-time known (checks are performed by
6663 -- Get_Component_Val), and that any subtypes or ranges are statically
6666 -- If the aggregate is not fully positional at this stage, then
6667 -- convert it to positional form. Either this will fail, in which
6668 -- case we can do nothing, or it will succeed, in which case we have
6669 -- succeeded in handling the aggregate and transforming it into a
6670 -- modular value, or it will stay an aggregate, in which case we
6671 -- have failed to create a packed value for it.
6673 if Present
(Component_Associations
(N
)) then
6674 Convert_To_Positional
6675 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
6676 return Nkind
(N
) /= N_Aggregate
;
6679 -- Otherwise we are all positional, so convert to proper value
6682 Lov
: constant Int
:= UI_To_Int
(Lob
);
6683 Hiv
: constant Int
:= UI_To_Int
(Hib
);
6685 Len
: constant Nat
:= Int
'Max (0, Hiv
- Lov
+ 1);
6686 -- The length of the array (number of elements)
6688 Aggregate_Val
: Uint
;
6689 -- Value of aggregate. The value is set in the low order bits of
6690 -- this value. For the little-endian case, the values are stored
6691 -- from low-order to high-order and for the big-endian case the
6692 -- values are stored from high-order to low-order. Note that gigi
6693 -- will take care of the conversions to left justify the value in
6694 -- the big endian case (because of left justified modular type
6695 -- processing), so we do not have to worry about that here.
6698 -- Integer literal for resulting constructed value
6701 -- Shift count from low order for next value
6704 -- Shift increment for loop
6707 -- Next expression from positional parameters of aggregate
6709 Left_Justified
: Boolean;
6710 -- Set True if we are filling the high order bits of the target
6711 -- value (i.e. the value is left justified).
6714 -- For little endian, we fill up the low order bits of the target
6715 -- value. For big endian we fill up the high order bits of the
6716 -- target value (which is a left justified modular value).
6718 Left_Justified
:= Bytes_Big_Endian
;
6720 -- Switch justification if using -gnatd8
6722 if Debug_Flag_8
then
6723 Left_Justified
:= not Left_Justified
;
6726 -- Switch justfification if reverse storage order
6728 if Reverse_Storage_Order
(Base_Type
(Typ
)) then
6729 Left_Justified
:= not Left_Justified
;
6732 if Left_Justified
then
6733 Shift
:= Csiz
* (Len
- 1);
6740 -- Loop to set the values
6743 Aggregate_Val
:= Uint_0
;
6745 Expr
:= First
(Expressions
(N
));
6746 Aggregate_Val
:= Get_Component_Val
(Expr
) * Uint_2
** Shift
;
6748 for J
in 2 .. Len
loop
6749 Shift
:= Shift
+ Incr
;
6752 Aggregate_Val
+ Get_Component_Val
(Expr
) * Uint_2
** Shift
;
6756 -- Now we can rewrite with the proper value
6758 Lit
:= Make_Integer_Literal
(Loc
, Intval
=> Aggregate_Val
);
6759 Set_Print_In_Hex
(Lit
);
6761 -- Construct the expression using this literal. Note that it is
6762 -- important to qualify the literal with its proper modular type
6763 -- since universal integer does not have the required range and
6764 -- also this is a left justified modular type, which is important
6765 -- in the big-endian case.
6768 Unchecked_Convert_To
(Typ
,
6769 Make_Qualified_Expression
(Loc
,
6771 New_Occurrence_Of
(Packed_Array_Impl_Type
(Typ
), Loc
),
6772 Expression
=> Lit
)));
6774 Analyze_And_Resolve
(N
, Typ
);
6782 end Packed_Array_Aggregate_Handled
;
6784 ----------------------------
6785 -- Has_Mutable_Components --
6786 ----------------------------
6788 function Has_Mutable_Components
(Typ
: Entity_Id
) return Boolean is
6792 Comp
:= First_Component
(Typ
);
6793 while Present
(Comp
) loop
6794 if Is_Record_Type
(Etype
(Comp
))
6795 and then Has_Discriminants
(Etype
(Comp
))
6796 and then not Is_Constrained
(Etype
(Comp
))
6801 Next_Component
(Comp
);
6805 end Has_Mutable_Components
;
6807 ------------------------------
6808 -- Initialize_Discriminants --
6809 ------------------------------
6811 procedure Initialize_Discriminants
(N
: Node_Id
; Typ
: Entity_Id
) is
6812 Loc
: constant Source_Ptr
:= Sloc
(N
);
6813 Bas
: constant Entity_Id
:= Base_Type
(Typ
);
6814 Par
: constant Entity_Id
:= Etype
(Bas
);
6815 Decl
: constant Node_Id
:= Parent
(Par
);
6819 if Is_Tagged_Type
(Bas
)
6820 and then Is_Derived_Type
(Bas
)
6821 and then Has_Discriminants
(Par
)
6822 and then Has_Discriminants
(Bas
)
6823 and then Number_Discriminants
(Bas
) /= Number_Discriminants
(Par
)
6824 and then Nkind
(Decl
) = N_Full_Type_Declaration
6825 and then Nkind
(Type_Definition
(Decl
)) = N_Record_Definition
6827 Present
(Variant_Part
(Component_List
(Type_Definition
(Decl
))))
6828 and then Nkind
(N
) /= N_Extension_Aggregate
6831 -- Call init proc to set discriminants.
6832 -- There should eventually be a special procedure for this ???
6834 Ref
:= New_Occurrence_Of
(Defining_Identifier
(N
), Loc
);
6835 Insert_Actions_After
(N
,
6836 Build_Initialization_Call
(Sloc
(N
), Ref
, Typ
));
6838 end Initialize_Discriminants
;
6845 (Obj_Type
: Entity_Id
;
6846 Typ
: Entity_Id
) return Boolean
6848 L1
, L2
, H1
, H2
: Node_Id
;
6851 -- No sliding if the type of the object is not established yet, if it is
6852 -- an unconstrained type whose actual subtype comes from the aggregate,
6853 -- or if the two types are identical.
6855 if not Is_Array_Type
(Obj_Type
) then
6858 elsif not Is_Constrained
(Obj_Type
) then
6861 elsif Typ
= Obj_Type
then
6865 -- Sliding can only occur along the first dimension
6867 Get_Index_Bounds
(First_Index
(Typ
), L1
, H1
);
6868 Get_Index_Bounds
(First_Index
(Obj_Type
), L2
, H2
);
6870 if not Is_OK_Static_Expression
(L1
) or else
6871 not Is_OK_Static_Expression
(L2
) or else
6872 not Is_OK_Static_Expression
(H1
) or else
6873 not Is_OK_Static_Expression
(H2
)
6877 return Expr_Value
(L1
) /= Expr_Value
(L2
)
6879 Expr_Value
(H1
) /= Expr_Value
(H2
);
6884 ----------------------------------
6885 -- Two_Dim_Packed_Array_Handled --
6886 ----------------------------------
6888 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean is
6889 Loc
: constant Source_Ptr
:= Sloc
(N
);
6890 Typ
: constant Entity_Id
:= Etype
(N
);
6891 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
6892 Comp_Size
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
6893 Packed_Array
: constant Entity_Id
:=
6894 Packed_Array_Impl_Type
(Base_Type
(Typ
));
6897 -- Expression in original aggregate
6900 -- One-dimensional subaggregate
6904 -- For now, only deal with cases where an integral number of elements
6905 -- fit in a single byte. This includes the most common boolean case.
6907 if not (Comp_Size
= 1 or else
6908 Comp_Size
= 2 or else
6914 Convert_To_Positional
6915 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
6917 -- Verify that all components are static
6919 if Nkind
(N
) = N_Aggregate
6920 and then Compile_Time_Known_Aggregate
(N
)
6924 -- The aggregate may have been re-analyzed and converted already
6926 elsif Nkind
(N
) /= N_Aggregate
then
6929 -- If component associations remain, the aggregate is not static
6931 elsif Present
(Component_Associations
(N
)) then
6935 One_Dim
:= First
(Expressions
(N
));
6936 while Present
(One_Dim
) loop
6937 if Present
(Component_Associations
(One_Dim
)) then
6941 One_Comp
:= First
(Expressions
(One_Dim
));
6942 while Present
(One_Comp
) loop
6943 if not Is_OK_Static_Expression
(One_Comp
) then
6954 -- Two-dimensional aggregate is now fully positional so pack one
6955 -- dimension to create a static one-dimensional array, and rewrite
6956 -- as an unchecked conversion to the original type.
6959 Byte_Size
: constant Int
:= UI_To_Int
(Component_Size
(Packed_Array
));
6960 -- The packed array type is a byte array
6963 -- Number of components accumulated in current byte
6966 -- Assembled list of packed values for equivalent aggregate
6969 -- integer value of component
6972 -- Step size for packing
6975 -- Endian-dependent start position for packing
6978 -- Current insertion position
6981 -- Component of packed array being assembled.
6988 -- Account for endianness. See corresponding comment in
6989 -- Packed_Array_Aggregate_Handled concerning the following.
6993 xor Reverse_Storage_Order
(Base_Type
(Typ
))
6995 Init_Shift
:= Byte_Size
- Comp_Size
;
7002 -- Iterate over each subaggregate
7004 Shift
:= Init_Shift
;
7005 One_Dim
:= First
(Expressions
(N
));
7006 while Present
(One_Dim
) loop
7007 One_Comp
:= First
(Expressions
(One_Dim
));
7008 while Present
(One_Comp
) loop
7009 if Packed_Num
= Byte_Size
/ Comp_Size
then
7011 -- Byte is complete, add to list of expressions
7013 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
7015 Shift
:= Init_Shift
;
7019 Comp_Val
:= Expr_Rep_Value
(One_Comp
);
7021 -- Adjust for bias, and strip proper number of bits
7023 if Has_Biased_Representation
(Ctyp
) then
7024 Comp_Val
:= Comp_Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
7027 Comp_Val
:= Comp_Val
mod Uint_2
** Comp_Size
;
7028 Val
:= UI_To_Int
(Val
+ Comp_Val
* Uint_2
** Shift
);
7029 Shift
:= Shift
+ Incr
;
7030 One_Comp
:= Next
(One_Comp
);
7031 Packed_Num
:= Packed_Num
+ 1;
7035 One_Dim
:= Next
(One_Dim
);
7038 if Packed_Num
> 0 then
7040 -- Add final incomplete byte if present
7042 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
7046 Unchecked_Convert_To
(Typ
,
7047 Make_Qualified_Expression
(Loc
,
7048 Subtype_Mark
=> New_Occurrence_Of
(Packed_Array
, Loc
),
7049 Expression
=> Make_Aggregate
(Loc
, Expressions
=> Comps
))));
7050 Analyze_And_Resolve
(N
);
7053 end Two_Dim_Packed_Array_Handled
;
7055 ---------------------
7056 -- Sort_Case_Table --
7057 ---------------------
7059 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
) is
7060 L
: constant Int
:= Case_Table
'First;
7061 U
: constant Int
:= Case_Table
'Last;
7069 T
:= Case_Table
(K
+ 1);
7073 and then Expr_Value
(Case_Table
(J
- 1).Choice_Lo
) >
7074 Expr_Value
(T
.Choice_Lo
)
7076 Case_Table
(J
) := Case_Table
(J
- 1);
7080 Case_Table
(J
) := T
;
7083 end Sort_Case_Table
;
7085 ----------------------------
7086 -- Static_Array_Aggregate --
7087 ----------------------------
7089 function Static_Array_Aggregate
(N
: Node_Id
) return Boolean is
7090 Bounds
: constant Node_Id
:= Aggregate_Bounds
(N
);
7092 Typ
: constant Entity_Id
:= Etype
(N
);
7093 Comp_Type
: constant Entity_Id
:= Component_Type
(Typ
);
7100 if Is_Tagged_Type
(Typ
)
7101 or else Is_Controlled
(Typ
)
7102 or else Is_Packed
(Typ
)
7108 and then Nkind
(Bounds
) = N_Range
7109 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
7110 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
7112 Lo
:= Low_Bound
(Bounds
);
7113 Hi
:= High_Bound
(Bounds
);
7115 if No
(Component_Associations
(N
)) then
7117 -- Verify that all components are static integers
7119 Expr
:= First
(Expressions
(N
));
7120 while Present
(Expr
) loop
7121 if Nkind
(Expr
) /= N_Integer_Literal
then
7131 -- We allow only a single named association, either a static
7132 -- range or an others_clause, with a static expression.
7134 Expr
:= First
(Component_Associations
(N
));
7136 if Present
(Expressions
(N
)) then
7139 elsif Present
(Next
(Expr
)) then
7142 elsif Present
(Next
(First
(Choices
(Expr
)))) then
7146 -- The aggregate is static if all components are literals,
7147 -- or else all its components are static aggregates for the
7148 -- component type. We also limit the size of a static aggregate
7149 -- to prevent runaway static expressions.
7151 if Is_Array_Type
(Comp_Type
)
7152 or else Is_Record_Type
(Comp_Type
)
7154 if Nkind
(Expression
(Expr
)) /= N_Aggregate
7156 not Compile_Time_Known_Aggregate
(Expression
(Expr
))
7161 elsif Nkind
(Expression
(Expr
)) /= N_Integer_Literal
then
7165 if not Aggr_Size_OK
(N
, Typ
) then
7169 -- Create a positional aggregate with the right number of
7170 -- copies of the expression.
7172 Agg
:= Make_Aggregate
(Sloc
(N
), New_List
, No_List
);
7174 for I
in UI_To_Int
(Intval
(Lo
)) .. UI_To_Int
(Intval
(Hi
))
7176 Append_To
(Expressions
(Agg
), New_Copy
(Expression
(Expr
)));
7178 -- The copied expression must be analyzed and resolved.
7179 -- Besides setting the type, this ensures that static
7180 -- expressions are appropriately marked as such.
7183 (Last
(Expressions
(Agg
)), Component_Type
(Typ
));
7186 Set_Aggregate_Bounds
(Agg
, Bounds
);
7187 Set_Etype
(Agg
, Typ
);
7190 Set_Compile_Time_Known_Aggregate
(N
);
7199 end Static_Array_Aggregate
;