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
;
2115 In_Aggr_Type
: Boolean;
2118 -- The constraints on the hidden discriminants, if present, are kept
2119 -- in the Stored_Constraint list of the type itself, or in that of
2120 -- the base type. If not in the constraints of the aggregate itself,
2121 -- we examine ancestors to find discriminants that are not renamed
2122 -- by other discriminants but constrained explicitly.
2124 In_Aggr_Type
:= True;
2126 Btype
:= Base_Type
(Typ
);
2127 while Is_Derived_Type
(Btype
)
2129 (Present
(Stored_Constraint
(Btype
))
2131 (In_Aggr_Type
and then Present
(Stored_Constraint
(Typ
))))
2133 Parent_Type
:= Etype
(Btype
);
2135 if not Has_Discriminants
(Parent_Type
) then
2139 Disc
:= First_Discriminant
(Parent_Type
);
2141 -- We know that one of the stored-constraint lists is present
2143 if Present
(Stored_Constraint
(Btype
)) then
2144 Discr_Val
:= First_Elmt
(Stored_Constraint
(Btype
));
2146 -- For private extension, stored constraint may be on full view
2148 elsif Is_Private_Type
(Btype
)
2149 and then Present
(Full_View
(Btype
))
2150 and then Present
(Stored_Constraint
(Full_View
(Btype
)))
2152 Discr_Val
:= First_Elmt
(Stored_Constraint
(Full_View
(Btype
)));
2155 Discr_Val
:= First_Elmt
(Stored_Constraint
(Typ
));
2158 while Present
(Discr_Val
) and then Present
(Disc
) loop
2160 -- Only those discriminants of the parent that are not
2161 -- renamed by discriminants of the derived type need to
2162 -- be added explicitly.
2164 if not Is_Entity_Name
(Node
(Discr_Val
))
2165 or else Ekind
(Entity
(Node
(Discr_Val
))) /= E_Discriminant
2168 Make_Selected_Component
(Loc
,
2169 Prefix
=> New_Copy_Tree
(Target
),
2170 Selector_Name
=> New_Occurrence_Of
(Disc
, Loc
));
2173 Make_OK_Assignment_Statement
(Loc
,
2175 Expression
=> New_Copy_Tree
(Node
(Discr_Val
)));
2177 Set_No_Ctrl_Actions
(Instr
);
2178 Append_To
(List
, Instr
);
2181 Next_Discriminant
(Disc
);
2182 Next_Elmt
(Discr_Val
);
2185 In_Aggr_Type
:= False;
2186 Btype
:= Base_Type
(Parent_Type
);
2188 end Init_Hidden_Discriminants
;
2190 -------------------------
2191 -- Is_Int_Range_Bounds --
2192 -------------------------
2194 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean is
2196 return Nkind
(Bounds
) = N_Range
2197 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
2198 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
;
2199 end Is_Int_Range_Bounds
;
2201 -----------------------------------
2202 -- Generate_Finalization_Actions --
2203 -----------------------------------
2205 procedure Generate_Finalization_Actions
is
2207 -- Do the work only the first time this is called
2209 if Finalization_Done
then
2213 Finalization_Done
:= True;
2215 -- Determine the external finalization list. It is either the
2216 -- finalization list of the outer-scope or the one coming from an
2217 -- outer aggregate. When the target is not a temporary, the proper
2218 -- scope is the scope of the target rather than the potentially
2219 -- transient current scope.
2221 if Is_Controlled
(Typ
) and then Ancestor_Is_Subtype_Mark
then
2222 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2223 Set_Assignment_OK
(Ref
);
2226 Make_Procedure_Call_Statement
(Loc
,
2229 (Find_Prim_Op
(Init_Typ
, Name_Initialize
), Loc
),
2230 Parameter_Associations
=> New_List
(New_Copy_Tree
(Ref
))));
2232 end Generate_Finalization_Actions
;
2234 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
;
2235 -- If default expression of a component mentions a discriminant of the
2236 -- type, it must be rewritten as the discriminant of the target object.
2238 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
;
2239 -- If the aggregate contains a self-reference, traverse each expression
2240 -- to replace a possible self-reference with a reference to the proper
2241 -- component of the target of the assignment.
2243 --------------------------
2244 -- Rewrite_Discriminant --
2245 --------------------------
2247 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
is
2249 if Is_Entity_Name
(Expr
)
2250 and then Present
(Entity
(Expr
))
2251 and then Ekind
(Entity
(Expr
)) = E_In_Parameter
2252 and then Present
(Discriminal_Link
(Entity
(Expr
)))
2253 and then Scope
(Discriminal_Link
(Entity
(Expr
))) =
2254 Base_Type
(Etype
(N
))
2257 Make_Selected_Component
(Loc
,
2258 Prefix
=> New_Copy_Tree
(Lhs
),
2259 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Expr
))));
2263 end Rewrite_Discriminant
;
2269 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
is
2271 -- Note regarding the Root_Type test below: Aggregate components for
2272 -- self-referential types include attribute references to the current
2273 -- instance, of the form: Typ'access, etc.. These references are
2274 -- rewritten as references to the target of the aggregate: the
2275 -- left-hand side of an assignment, the entity in a declaration,
2276 -- or a temporary. Without this test, we would improperly extended
2277 -- this rewriting to attribute references whose prefix was not the
2278 -- type of the aggregate.
2280 if Nkind
(Expr
) = N_Attribute_Reference
2281 and then Is_Entity_Name
(Prefix
(Expr
))
2282 and then Is_Type
(Entity
(Prefix
(Expr
)))
2283 and then Root_Type
(Etype
(N
)) = Root_Type
(Entity
(Prefix
(Expr
)))
2285 if Is_Entity_Name
(Lhs
) then
2286 Rewrite
(Prefix
(Expr
),
2287 New_Occurrence_Of
(Entity
(Lhs
), Loc
));
2289 elsif Nkind
(Lhs
) = N_Selected_Component
then
2291 Make_Attribute_Reference
(Loc
,
2292 Attribute_Name
=> Name_Unrestricted_Access
,
2293 Prefix
=> New_Copy_Tree
(Lhs
)));
2294 Set_Analyzed
(Parent
(Expr
), False);
2298 Make_Attribute_Reference
(Loc
,
2299 Attribute_Name
=> Name_Unrestricted_Access
,
2300 Prefix
=> New_Copy_Tree
(Lhs
)));
2301 Set_Analyzed
(Parent
(Expr
), False);
2308 procedure Replace_Self_Reference
is
2309 new Traverse_Proc
(Replace_Type
);
2311 procedure Replace_Discriminants
is
2312 new Traverse_Proc
(Rewrite_Discriminant
);
2314 -- Start of processing for Build_Record_Aggr_Code
2317 if Has_Self_Reference
(N
) then
2318 Replace_Self_Reference
(N
);
2321 -- If the target of the aggregate is class-wide, we must convert it
2322 -- to the actual type of the aggregate, so that the proper components
2323 -- are visible. We know already that the types are compatible.
2325 if Present
(Etype
(Lhs
))
2326 and then Is_Class_Wide_Type
(Etype
(Lhs
))
2328 Target
:= Unchecked_Convert_To
(Typ
, Lhs
);
2333 -- Deal with the ancestor part of extension aggregates or with the
2334 -- discriminants of the root type.
2336 if Nkind
(N
) = N_Extension_Aggregate
then
2338 Ancestor
: constant Node_Id
:= Ancestor_Part
(N
);
2342 -- If the ancestor part is a subtype mark "T", we generate
2344 -- init-proc (T (tmp)); if T is constrained and
2345 -- init-proc (S (tmp)); where S applies an appropriate
2346 -- constraint if T is unconstrained
2348 if Is_Entity_Name
(Ancestor
)
2349 and then Is_Type
(Entity
(Ancestor
))
2351 Ancestor_Is_Subtype_Mark
:= True;
2353 if Is_Constrained
(Entity
(Ancestor
)) then
2354 Init_Typ
:= Entity
(Ancestor
);
2356 -- For an ancestor part given by an unconstrained type mark,
2357 -- create a subtype constrained by appropriate corresponding
2358 -- discriminant values coming from either associations of the
2359 -- aggregate or a constraint on a parent type. The subtype will
2360 -- be used to generate the correct default value for the
2363 elsif Has_Discriminants
(Entity
(Ancestor
)) then
2365 Anc_Typ
: constant Entity_Id
:= Entity
(Ancestor
);
2366 Anc_Constr
: constant List_Id
:= New_List
;
2367 Discrim
: Entity_Id
;
2368 Disc_Value
: Node_Id
;
2369 New_Indic
: Node_Id
;
2370 Subt_Decl
: Node_Id
;
2373 Discrim
:= First_Discriminant
(Anc_Typ
);
2374 while Present
(Discrim
) loop
2375 Disc_Value
:= Ancestor_Discriminant_Value
(Discrim
);
2377 -- If no usable discriminant in ancestors, check
2378 -- whether aggregate has an explicit value for it.
2380 if No
(Disc_Value
) then
2382 Get_Explicit_Discriminant_Value
(Discrim
);
2385 Append_To
(Anc_Constr
, Disc_Value
);
2386 Next_Discriminant
(Discrim
);
2390 Make_Subtype_Indication
(Loc
,
2391 Subtype_Mark
=> New_Occurrence_Of
(Anc_Typ
, Loc
),
2393 Make_Index_Or_Discriminant_Constraint
(Loc
,
2394 Constraints
=> Anc_Constr
));
2396 Init_Typ
:= Create_Itype
(Ekind
(Anc_Typ
), N
);
2399 Make_Subtype_Declaration
(Loc
,
2400 Defining_Identifier
=> Init_Typ
,
2401 Subtype_Indication
=> New_Indic
);
2403 -- Itypes must be analyzed with checks off Declaration
2404 -- must have a parent for proper handling of subsidiary
2407 Set_Parent
(Subt_Decl
, N
);
2408 Analyze
(Subt_Decl
, Suppress
=> All_Checks
);
2412 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2413 Set_Assignment_OK
(Ref
);
2415 if not Is_Interface
(Init_Typ
) then
2417 Build_Initialization_Call
(Loc
,
2420 In_Init_Proc
=> Within_Init_Proc
,
2421 With_Default_Init
=> Has_Default_Init_Comps
(N
)
2423 Has_Task
(Base_Type
(Init_Typ
))));
2425 if Is_Constrained
(Entity
(Ancestor
))
2426 and then Has_Discriminants
(Entity
(Ancestor
))
2428 Check_Ancestor_Discriminants
(Entity
(Ancestor
));
2432 -- Handle calls to C++ constructors
2434 elsif Is_CPP_Constructor_Call
(Ancestor
) then
2435 Init_Typ
:= Etype
(Ancestor
);
2436 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2437 Set_Assignment_OK
(Ref
);
2440 Build_Initialization_Call
(Loc
,
2443 In_Init_Proc
=> Within_Init_Proc
,
2444 With_Default_Init
=> Has_Default_Init_Comps
(N
),
2445 Constructor_Ref
=> Ancestor
));
2447 -- Ada 2005 (AI-287): If the ancestor part is an aggregate of
2448 -- limited type, a recursive call expands the ancestor. Note that
2449 -- in the limited case, the ancestor part must be either a
2450 -- function call (possibly qualified, or wrapped in an unchecked
2451 -- conversion) or aggregate (definitely qualified).
2453 -- The ancestor part can also be a function call (that may be
2454 -- transformed into an explicit dereference) or a qualification
2457 elsif Is_Limited_Type
(Etype
(Ancestor
))
2458 and then Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
2459 N_Extension_Aggregate
)
2461 Ancestor_Is_Expression
:= True;
2463 -- Set up finalization data for enclosing record, because
2464 -- controlled subcomponents of the ancestor part will be
2467 Generate_Finalization_Actions
;
2470 Build_Record_Aggr_Code
2471 (N
=> Unqualify
(Ancestor
),
2472 Typ
=> Etype
(Unqualify
(Ancestor
)),
2475 -- If the ancestor part is an expression "E", we generate
2479 -- In Ada 2005, this includes the case of a (possibly qualified)
2480 -- limited function call. The assignment will turn into a
2481 -- build-in-place function call (for further details, see
2482 -- Make_Build_In_Place_Call_In_Assignment).
2485 Ancestor_Is_Expression
:= True;
2486 Init_Typ
:= Etype
(Ancestor
);
2488 -- If the ancestor part is an aggregate, force its full
2489 -- expansion, which was delayed.
2491 if Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
2492 N_Extension_Aggregate
)
2494 Set_Analyzed
(Ancestor
, False);
2495 Set_Analyzed
(Expression
(Ancestor
), False);
2498 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2499 Set_Assignment_OK
(Ref
);
2501 -- Make the assignment without usual controlled actions, since
2502 -- we only want to Adjust afterwards, but not to Finalize
2503 -- beforehand. Add manual Adjust when necessary.
2505 Assign
:= New_List
(
2506 Make_OK_Assignment_Statement
(Loc
,
2508 Expression
=> Ancestor
));
2509 Set_No_Ctrl_Actions
(First
(Assign
));
2511 -- Assign the tag now to make sure that the dispatching call in
2512 -- the subsequent deep_adjust works properly (unless VM_Target,
2513 -- where tags are implicit).
2515 if Tagged_Type_Expansion
then
2517 Make_OK_Assignment_Statement
(Loc
,
2519 Make_Selected_Component
(Loc
,
2520 Prefix
=> New_Copy_Tree
(Target
),
2523 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
2526 Unchecked_Convert_To
(RTE
(RE_Tag
),
2529 (Access_Disp_Table
(Base_Type
(Typ
)))),
2532 Set_Assignment_OK
(Name
(Instr
));
2533 Append_To
(Assign
, Instr
);
2535 -- Ada 2005 (AI-251): If tagged type has progenitors we must
2536 -- also initialize tags of the secondary dispatch tables.
2538 if Has_Interfaces
(Base_Type
(Typ
)) then
2540 (Typ
=> Base_Type
(Typ
),
2542 Stmts_List
=> Assign
);
2546 -- Call Adjust manually
2548 if Needs_Finalization
(Etype
(Ancestor
))
2549 and then not Is_Limited_Type
(Etype
(Ancestor
))
2553 (Obj_Ref
=> New_Copy_Tree
(Ref
),
2554 Typ
=> Etype
(Ancestor
)));
2558 Make_Unsuppress_Block
(Loc
, Name_Discriminant_Check
, Assign
));
2560 if Has_Discriminants
(Init_Typ
) then
2561 Check_Ancestor_Discriminants
(Init_Typ
);
2566 -- Generate assignments of hidden discriminants. If the base type is
2567 -- an unchecked union, the discriminants are unknown to the back-end
2568 -- and absent from a value of the type, so assignments for them are
2571 if Has_Discriminants
(Typ
)
2572 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
2574 Init_Hidden_Discriminants
(Typ
, L
);
2577 -- Normal case (not an extension aggregate)
2580 -- Generate the discriminant expressions, component by component.
2581 -- If the base type is an unchecked union, the discriminants are
2582 -- unknown to the back-end and absent from a value of the type, so
2583 -- assignments for them are not emitted.
2585 if Has_Discriminants
(Typ
)
2586 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
2588 Init_Hidden_Discriminants
(Typ
, L
);
2590 -- Generate discriminant init values for the visible discriminants
2593 Discriminant
: Entity_Id
;
2594 Discriminant_Value
: Node_Id
;
2597 Discriminant
:= First_Stored_Discriminant
(Typ
);
2598 while Present
(Discriminant
) loop
2600 Make_Selected_Component
(Loc
,
2601 Prefix
=> New_Copy_Tree
(Target
),
2602 Selector_Name
=> New_Occurrence_Of
(Discriminant
, Loc
));
2604 Discriminant_Value
:=
2605 Get_Discriminant_Value
(
2608 Discriminant_Constraint
(N_Typ
));
2611 Make_OK_Assignment_Statement
(Loc
,
2613 Expression
=> New_Copy_Tree
(Discriminant_Value
));
2615 Set_No_Ctrl_Actions
(Instr
);
2616 Append_To
(L
, Instr
);
2618 Next_Stored_Discriminant
(Discriminant
);
2624 -- For CPP types we generate an implicit call to the C++ default
2625 -- constructor to ensure the proper initialization of the _Tag
2628 if Is_CPP_Class
(Root_Type
(Typ
)) and then CPP_Num_Prims
(Typ
) > 0 then
2629 Invoke_Constructor
: declare
2630 CPP_Parent
: constant Entity_Id
:= Enclosing_CPP_Parent
(Typ
);
2632 procedure Invoke_IC_Proc
(T
: Entity_Id
);
2633 -- Recursive routine used to climb to parents. Required because
2634 -- parents must be initialized before descendants to ensure
2635 -- propagation of inherited C++ slots.
2637 --------------------
2638 -- Invoke_IC_Proc --
2639 --------------------
2641 procedure Invoke_IC_Proc
(T
: Entity_Id
) is
2643 -- Avoid generating extra calls. Initialization required
2644 -- only for types defined from the level of derivation of
2645 -- type of the constructor and the type of the aggregate.
2647 if T
= CPP_Parent
then
2651 Invoke_IC_Proc
(Etype
(T
));
2653 -- Generate call to the IC routine
2655 if Present
(CPP_Init_Proc
(T
)) then
2657 Make_Procedure_Call_Statement
(Loc
,
2658 New_Occurrence_Of
(CPP_Init_Proc
(T
), Loc
)));
2662 -- Start of processing for Invoke_Constructor
2665 -- Implicit invocation of the C++ constructor
2667 if Nkind
(N
) = N_Aggregate
then
2669 Make_Procedure_Call_Statement
(Loc
,
2671 New_Occurrence_Of
(Base_Init_Proc
(CPP_Parent
), Loc
),
2672 Parameter_Associations
=> New_List
(
2673 Unchecked_Convert_To
(CPP_Parent
,
2674 New_Copy_Tree
(Lhs
)))));
2677 Invoke_IC_Proc
(Typ
);
2678 end Invoke_Constructor
;
2681 -- Generate the assignments, component by component
2683 -- tmp.comp1 := Expr1_From_Aggr;
2684 -- tmp.comp2 := Expr2_From_Aggr;
2687 Comp
:= First
(Component_Associations
(N
));
2688 while Present
(Comp
) loop
2689 Selector
:= Entity
(First
(Choices
(Comp
)));
2693 if Is_CPP_Constructor_Call
(Expression
(Comp
)) then
2695 Build_Initialization_Call
(Loc
,
2697 Make_Selected_Component
(Loc
,
2698 Prefix
=> New_Copy_Tree
(Target
),
2699 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
)),
2700 Typ
=> Etype
(Selector
),
2702 With_Default_Init
=> True,
2703 Constructor_Ref
=> Expression
(Comp
)));
2705 -- Ada 2005 (AI-287): For each default-initialized component generate
2706 -- a call to the corresponding IP subprogram if available.
2708 elsif Box_Present
(Comp
)
2709 and then Has_Non_Null_Base_Init_Proc
(Etype
(Selector
))
2711 if Ekind
(Selector
) /= E_Discriminant
then
2712 Generate_Finalization_Actions
;
2715 -- Ada 2005 (AI-287): If the component type has tasks then
2716 -- generate the activation chain and master entities (except
2717 -- in case of an allocator because in that case these entities
2718 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
2721 Ctype
: constant Entity_Id
:= Etype
(Selector
);
2722 Inside_Allocator
: Boolean := False;
2723 P
: Node_Id
:= Parent
(N
);
2726 if Is_Task_Type
(Ctype
) or else Has_Task
(Ctype
) then
2727 while Present
(P
) loop
2728 if Nkind
(P
) = N_Allocator
then
2729 Inside_Allocator
:= True;
2736 if not Inside_Init_Proc
and not Inside_Allocator
then
2737 Build_Activation_Chain_Entity
(N
);
2743 Build_Initialization_Call
(Loc
,
2744 Id_Ref
=> Make_Selected_Component
(Loc
,
2745 Prefix
=> New_Copy_Tree
(Target
),
2747 New_Occurrence_Of
(Selector
, Loc
)),
2748 Typ
=> Etype
(Selector
),
2750 With_Default_Init
=> True));
2752 -- Prepare for component assignment
2754 elsif Ekind
(Selector
) /= E_Discriminant
2755 or else Nkind
(N
) = N_Extension_Aggregate
2757 -- All the discriminants have now been assigned
2759 -- This is now a good moment to initialize and attach all the
2760 -- controllers. Their position may depend on the discriminants.
2762 if Ekind
(Selector
) /= E_Discriminant
then
2763 Generate_Finalization_Actions
;
2766 Comp_Type
:= Underlying_Type
(Etype
(Selector
));
2768 Make_Selected_Component
(Loc
,
2769 Prefix
=> New_Copy_Tree
(Target
),
2770 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
));
2772 if Nkind
(Expression
(Comp
)) = N_Qualified_Expression
then
2773 Expr_Q
:= Expression
(Expression
(Comp
));
2775 Expr_Q
:= Expression
(Comp
);
2778 -- Now either create the assignment or generate the code for the
2779 -- inner aggregate top-down.
2781 if Is_Delayed_Aggregate
(Expr_Q
) then
2783 -- We have the following case of aggregate nesting inside
2784 -- an object declaration:
2786 -- type Arr_Typ is array (Integer range <>) of ...;
2788 -- type Rec_Typ (...) is record
2789 -- Obj_Arr_Typ : Arr_Typ (A .. B);
2792 -- Obj_Rec_Typ : Rec_Typ := (...,
2793 -- Obj_Arr_Typ => (X => (...), Y => (...)));
2795 -- The length of the ranges of the aggregate and Obj_Add_Typ
2796 -- are equal (B - A = Y - X), but they do not coincide (X /=
2797 -- A and B /= Y). This case requires array sliding which is
2798 -- performed in the following manner:
2800 -- subtype Arr_Sub is Arr_Typ (X .. Y);
2802 -- Temp (X) := (...);
2804 -- Temp (Y) := (...);
2805 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
2807 if Ekind
(Comp_Type
) = E_Array_Subtype
2808 and then Is_Int_Range_Bounds
(Aggregate_Bounds
(Expr_Q
))
2809 and then Is_Int_Range_Bounds
(First_Index
(Comp_Type
))
2811 Compatible_Int_Bounds
2812 (Agg_Bounds
=> Aggregate_Bounds
(Expr_Q
),
2813 Typ_Bounds
=> First_Index
(Comp_Type
))
2815 -- Create the array subtype with bounds equal to those of
2816 -- the corresponding aggregate.
2819 SubE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
2821 SubD
: constant Node_Id
:=
2822 Make_Subtype_Declaration
(Loc
,
2823 Defining_Identifier
=> SubE
,
2824 Subtype_Indication
=>
2825 Make_Subtype_Indication
(Loc
,
2827 New_Occurrence_Of
(Etype
(Comp_Type
), Loc
),
2829 Make_Index_Or_Discriminant_Constraint
2831 Constraints
=> New_List
(
2833 (Aggregate_Bounds
(Expr_Q
))))));
2835 -- Create a temporary array of the above subtype which
2836 -- will be used to capture the aggregate assignments.
2838 TmpE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A', N
);
2840 TmpD
: constant Node_Id
:=
2841 Make_Object_Declaration
(Loc
,
2842 Defining_Identifier
=> TmpE
,
2843 Object_Definition
=> New_Occurrence_Of
(SubE
, Loc
));
2846 Set_No_Initialization
(TmpD
);
2847 Append_To
(L
, SubD
);
2848 Append_To
(L
, TmpD
);
2850 -- Expand aggregate into assignments to the temp array
2853 Late_Expansion
(Expr_Q
, Comp_Type
,
2854 New_Occurrence_Of
(TmpE
, Loc
)));
2859 Make_Assignment_Statement
(Loc
,
2860 Name
=> New_Copy_Tree
(Comp_Expr
),
2861 Expression
=> New_Occurrence_Of
(TmpE
, Loc
)));
2864 -- Normal case (sliding not required)
2868 Late_Expansion
(Expr_Q
, Comp_Type
, Comp_Expr
));
2871 -- Expr_Q is not delayed aggregate
2874 if Has_Discriminants
(Typ
) then
2875 Replace_Discriminants
(Expr_Q
);
2877 -- If the component is an array type that depends on
2878 -- discriminants, and the expression is a single Others
2879 -- clause, create an explicit subtype for it because the
2880 -- backend has troubles recovering the actual bounds.
2882 if Nkind
(Expr_Q
) = N_Aggregate
2883 and then Is_Array_Type
(Comp_Type
)
2884 and then Present
(Component_Associations
(Expr_Q
))
2887 Assoc
: constant Node_Id
:=
2888 First
(Component_Associations
(Expr_Q
));
2892 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
2895 Build_Actual_Subtype_Of_Component
2896 (Comp_Type
, Comp_Expr
);
2898 -- If the component type does not in fact depend on
2899 -- discriminants, the subtype declaration is empty.
2901 if Present
(Decl
) then
2902 Append_To
(L
, Decl
);
2903 Set_Etype
(Comp_Expr
, Defining_Entity
(Decl
));
2911 Make_OK_Assignment_Statement
(Loc
,
2913 Expression
=> Expr_Q
);
2915 Set_No_Ctrl_Actions
(Instr
);
2916 Append_To
(L
, Instr
);
2918 -- Adjust the tag if tagged (because of possible view
2919 -- conversions), unless compiling for a VM where tags are
2922 -- tmp.comp._tag := comp_typ'tag;
2924 if Is_Tagged_Type
(Comp_Type
)
2925 and then Tagged_Type_Expansion
2928 Make_OK_Assignment_Statement
(Loc
,
2930 Make_Selected_Component
(Loc
,
2931 Prefix
=> New_Copy_Tree
(Comp_Expr
),
2934 (First_Tag_Component
(Comp_Type
), Loc
)),
2937 Unchecked_Convert_To
(RTE
(RE_Tag
),
2939 (Node
(First_Elmt
(Access_Disp_Table
(Comp_Type
))),
2942 Append_To
(L
, Instr
);
2946 -- Adjust (tmp.comp);
2948 if Needs_Finalization
(Comp_Type
)
2949 and then not Is_Limited_Type
(Comp_Type
)
2953 (Obj_Ref
=> New_Copy_Tree
(Comp_Expr
),
2958 -- comment would be good here ???
2960 elsif Ekind
(Selector
) = E_Discriminant
2961 and then Nkind
(N
) /= N_Extension_Aggregate
2962 and then Nkind
(Parent
(N
)) = N_Component_Association
2963 and then Is_Constrained
(Typ
)
2965 -- We must check that the discriminant value imposed by the
2966 -- context is the same as the value given in the subaggregate,
2967 -- because after the expansion into assignments there is no
2968 -- record on which to perform a regular discriminant check.
2975 D_Val
:= First_Elmt
(Discriminant_Constraint
(Typ
));
2976 Disc
:= First_Discriminant
(Typ
);
2977 while Chars
(Disc
) /= Chars
(Selector
) loop
2978 Next_Discriminant
(Disc
);
2982 pragma Assert
(Present
(D_Val
));
2984 -- This check cannot performed for components that are
2985 -- constrained by a current instance, because this is not a
2986 -- value that can be compared with the actual constraint.
2988 if Nkind
(Node
(D_Val
)) /= N_Attribute_Reference
2989 or else not Is_Entity_Name
(Prefix
(Node
(D_Val
)))
2990 or else not Is_Type
(Entity
(Prefix
(Node
(D_Val
))))
2993 Make_Raise_Constraint_Error
(Loc
,
2996 Left_Opnd
=> New_Copy_Tree
(Node
(D_Val
)),
2997 Right_Opnd
=> Expression
(Comp
)),
2998 Reason
=> CE_Discriminant_Check_Failed
));
3001 -- Find self-reference in previous discriminant assignment,
3002 -- and replace with proper expression.
3009 while Present
(Ass
) loop
3010 if Nkind
(Ass
) = N_Assignment_Statement
3011 and then Nkind
(Name
(Ass
)) = N_Selected_Component
3012 and then Chars
(Selector_Name
(Name
(Ass
))) =
3016 (Ass
, New_Copy_Tree
(Expression
(Comp
)));
3029 -- If the type is tagged, the tag needs to be initialized (unless we
3030 -- are in VM-mode where tags are implicit). It is done late in the
3031 -- initialization process because in some cases, we call the init
3032 -- proc of an ancestor which will not leave out the right tag.
3034 if Ancestor_Is_Expression
then
3037 -- For CPP types we generated a call to the C++ default constructor
3038 -- before the components have been initialized to ensure the proper
3039 -- initialization of the _Tag component (see above).
3041 elsif Is_CPP_Class
(Typ
) then
3044 elsif Is_Tagged_Type
(Typ
) and then Tagged_Type_Expansion
then
3046 Make_OK_Assignment_Statement
(Loc
,
3048 Make_Selected_Component
(Loc
,
3049 Prefix
=> New_Copy_Tree
(Target
),
3052 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
3055 Unchecked_Convert_To
(RTE
(RE_Tag
),
3057 (Node
(First_Elmt
(Access_Disp_Table
(Base_Type
(Typ
)))),
3060 Append_To
(L
, Instr
);
3062 -- Ada 2005 (AI-251): If the tagged type has been derived from an
3063 -- abstract interfaces we must also initialize the tags of the
3064 -- secondary dispatch tables.
3066 if Has_Interfaces
(Base_Type
(Typ
)) then
3068 (Typ
=> Base_Type
(Typ
),
3074 -- If the controllers have not been initialized yet (by lack of non-
3075 -- discriminant components), let's do it now.
3077 Generate_Finalization_Actions
;
3080 end Build_Record_Aggr_Code
;
3082 ---------------------------------------
3083 -- Collect_Initialization_Statements --
3084 ---------------------------------------
3086 procedure Collect_Initialization_Statements
3089 Node_After
: Node_Id
)
3091 Loc
: constant Source_Ptr
:= Sloc
(N
);
3092 Init_Actions
: constant List_Id
:= New_List
;
3093 Init_Node
: Node_Id
;
3094 Comp_Stmt
: Node_Id
;
3097 -- Nothing to do if Obj is already frozen, as in this case we known we
3098 -- won't need to move the initialization statements about later on.
3100 if Is_Frozen
(Obj
) then
3105 while Next
(Init_Node
) /= Node_After
loop
3106 Append_To
(Init_Actions
, Remove_Next
(Init_Node
));
3109 if not Is_Empty_List
(Init_Actions
) then
3110 Comp_Stmt
:= Make_Compound_Statement
(Loc
, Actions
=> Init_Actions
);
3111 Insert_Action_After
(Init_Node
, Comp_Stmt
);
3112 Set_Initialization_Statements
(Obj
, Comp_Stmt
);
3114 end Collect_Initialization_Statements
;
3116 -------------------------------
3117 -- Convert_Aggr_In_Allocator --
3118 -------------------------------
3120 procedure Convert_Aggr_In_Allocator
3125 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3126 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3127 Temp
: constant Entity_Id
:= Defining_Identifier
(Decl
);
3129 Occ
: constant Node_Id
:=
3130 Unchecked_Convert_To
(Typ
,
3131 Make_Explicit_Dereference
(Loc
, New_Occurrence_Of
(Temp
, Loc
)));
3134 if Is_Array_Type
(Typ
) then
3135 Convert_Array_Aggr_In_Allocator
(Decl
, Aggr
, Occ
);
3137 elsif Has_Default_Init_Comps
(Aggr
) then
3139 L
: constant List_Id
:= New_List
;
3140 Init_Stmts
: List_Id
;
3143 Init_Stmts
:= Late_Expansion
(Aggr
, Typ
, Occ
);
3145 if Has_Task
(Typ
) then
3146 Build_Task_Allocate_Block_With_Init_Stmts
(L
, Aggr
, Init_Stmts
);
3147 Insert_Actions
(Alloc
, L
);
3149 Insert_Actions
(Alloc
, Init_Stmts
);
3154 Insert_Actions
(Alloc
, Late_Expansion
(Aggr
, Typ
, Occ
));
3156 end Convert_Aggr_In_Allocator
;
3158 --------------------------------
3159 -- Convert_Aggr_In_Assignment --
3160 --------------------------------
3162 procedure Convert_Aggr_In_Assignment
(N
: Node_Id
) is
3163 Aggr
: Node_Id
:= Expression
(N
);
3164 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3165 Occ
: constant Node_Id
:= New_Copy_Tree
(Name
(N
));
3168 if Nkind
(Aggr
) = N_Qualified_Expression
then
3169 Aggr
:= Expression
(Aggr
);
3172 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3173 end Convert_Aggr_In_Assignment
;
3175 ---------------------------------
3176 -- Convert_Aggr_In_Object_Decl --
3177 ---------------------------------
3179 procedure Convert_Aggr_In_Object_Decl
(N
: Node_Id
) is
3180 Obj
: constant Entity_Id
:= Defining_Identifier
(N
);
3181 Aggr
: Node_Id
:= Expression
(N
);
3182 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3183 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3184 Occ
: constant Node_Id
:= New_Occurrence_Of
(Obj
, Loc
);
3186 function Discriminants_Ok
return Boolean;
3187 -- If the object type is constrained, the discriminants in the
3188 -- aggregate must be checked against the discriminants of the subtype.
3189 -- This cannot be done using Apply_Discriminant_Checks because after
3190 -- expansion there is no aggregate left to check.
3192 ----------------------
3193 -- Discriminants_Ok --
3194 ----------------------
3196 function Discriminants_Ok
return Boolean is
3197 Cond
: Node_Id
:= Empty
;
3206 D
:= First_Discriminant
(Typ
);
3207 Disc1
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3208 Disc2
:= First_Elmt
(Discriminant_Constraint
(Etype
(Obj
)));
3209 while Present
(Disc1
) and then Present
(Disc2
) loop
3210 Val1
:= Node
(Disc1
);
3211 Val2
:= Node
(Disc2
);
3213 if not Is_OK_Static_Expression
(Val1
)
3214 or else not Is_OK_Static_Expression
(Val2
)
3216 Check
:= Make_Op_Ne
(Loc
,
3217 Left_Opnd
=> Duplicate_Subexpr
(Val1
),
3218 Right_Opnd
=> Duplicate_Subexpr
(Val2
));
3224 Cond
:= Make_Or_Else
(Loc
,
3226 Right_Opnd
=> Check
);
3229 elsif Expr_Value
(Val1
) /= Expr_Value
(Val2
) then
3230 Apply_Compile_Time_Constraint_Error
(Aggr
,
3231 Msg
=> "incorrect value for discriminant&??",
3232 Reason
=> CE_Discriminant_Check_Failed
,
3237 Next_Discriminant
(D
);
3242 -- If any discriminant constraint is non-static, emit a check
3244 if Present
(Cond
) then
3246 Make_Raise_Constraint_Error
(Loc
,
3248 Reason
=> CE_Discriminant_Check_Failed
));
3252 end Discriminants_Ok
;
3254 -- Start of processing for Convert_Aggr_In_Object_Decl
3257 Set_Assignment_OK
(Occ
);
3259 if Nkind
(Aggr
) = N_Qualified_Expression
then
3260 Aggr
:= Expression
(Aggr
);
3263 if Has_Discriminants
(Typ
)
3264 and then Typ
/= Etype
(Obj
)
3265 and then Is_Constrained
(Etype
(Obj
))
3266 and then not Discriminants_Ok
3271 -- If the context is an extended return statement, it has its own
3272 -- finalization machinery (i.e. works like a transient scope) and
3273 -- we do not want to create an additional one, because objects on
3274 -- the finalization list of the return must be moved to the caller's
3275 -- finalization list to complete the return.
3277 -- However, if the aggregate is limited, it is built in place, and the
3278 -- controlled components are not assigned to intermediate temporaries
3279 -- so there is no need for a transient scope in this case either.
3281 if Requires_Transient_Scope
(Typ
)
3282 and then Ekind
(Current_Scope
) /= E_Return_Statement
3283 and then not Is_Limited_Type
(Typ
)
3285 Establish_Transient_Scope
3288 Is_Controlled
(Typ
) or else Has_Controlled_Component
(Typ
));
3292 Node_After
: constant Node_Id
:= Next
(N
);
3294 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3295 Collect_Initialization_Statements
(Obj
, N
, Node_After
);
3297 Set_No_Initialization
(N
);
3298 Initialize_Discriminants
(N
, Typ
);
3299 end Convert_Aggr_In_Object_Decl
;
3301 -------------------------------------
3302 -- Convert_Array_Aggr_In_Allocator --
3303 -------------------------------------
3305 procedure Convert_Array_Aggr_In_Allocator
3310 Aggr_Code
: List_Id
;
3311 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3312 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
3315 -- The target is an explicit dereference of the allocated object.
3316 -- Generate component assignments to it, as for an aggregate that
3317 -- appears on the right-hand side of an assignment statement.
3320 Build_Array_Aggr_Code
(Aggr
,
3322 Index
=> First_Index
(Typ
),
3324 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
3326 Insert_Actions_After
(Decl
, Aggr_Code
);
3327 end Convert_Array_Aggr_In_Allocator
;
3329 ----------------------------
3330 -- Convert_To_Assignments --
3331 ----------------------------
3333 procedure Convert_To_Assignments
(N
: Node_Id
; Typ
: Entity_Id
) is
3334 Loc
: constant Source_Ptr
:= Sloc
(N
);
3338 Aggr_Code
: List_Id
;
3340 Target_Expr
: Node_Id
;
3341 Parent_Kind
: Node_Kind
;
3342 Unc_Decl
: Boolean := False;
3343 Parent_Node
: Node_Id
;
3346 pragma Assert
(not Is_Static_Dispatch_Table_Aggregate
(N
));
3347 pragma Assert
(Is_Record_Type
(Typ
));
3349 Parent_Node
:= Parent
(N
);
3350 Parent_Kind
:= Nkind
(Parent_Node
);
3352 if Parent_Kind
= N_Qualified_Expression
then
3354 -- Check if we are in a unconstrained declaration because in this
3355 -- case the current delayed expansion mechanism doesn't work when
3356 -- the declared object size depend on the initializing expr.
3359 Parent_Node
:= Parent
(Parent_Node
);
3360 Parent_Kind
:= Nkind
(Parent_Node
);
3362 if Parent_Kind
= N_Object_Declaration
then
3364 not Is_Entity_Name
(Object_Definition
(Parent_Node
))
3365 or else Has_Discriminants
3366 (Entity
(Object_Definition
(Parent_Node
)))
3367 or else Is_Class_Wide_Type
3368 (Entity
(Object_Definition
(Parent_Node
)));
3373 -- Just set the Delay flag in the cases where the transformation will be
3374 -- done top down from above.
3378 -- Internal aggregate (transformed when expanding the parent)
3380 or else Parent_Kind
= N_Aggregate
3381 or else Parent_Kind
= N_Extension_Aggregate
3382 or else Parent_Kind
= N_Component_Association
3384 -- Allocator (see Convert_Aggr_In_Allocator)
3386 or else Parent_Kind
= N_Allocator
3388 -- Object declaration (see Convert_Aggr_In_Object_Decl)
3390 or else (Parent_Kind
= N_Object_Declaration
and then not Unc_Decl
)
3392 -- Safe assignment (see Convert_Aggr_Assignments). So far only the
3393 -- assignments in init procs are taken into account.
3395 or else (Parent_Kind
= N_Assignment_Statement
3396 and then Inside_Init_Proc
)
3398 -- (Ada 2005) An inherently limited type in a return statement, which
3399 -- will be handled in a build-in-place fashion, and may be rewritten
3400 -- as an extended return and have its own finalization machinery.
3401 -- In the case of a simple return, the aggregate needs to be delayed
3402 -- until the scope for the return statement has been created, so
3403 -- that any finalization chain will be associated with that scope.
3404 -- For extended returns, we delay expansion to avoid the creation
3405 -- of an unwanted transient scope that could result in premature
3406 -- finalization of the return object (which is built in place
3407 -- within the caller's scope).
3410 (Is_Limited_View
(Typ
)
3412 (Nkind
(Parent
(Parent_Node
)) = N_Extended_Return_Statement
3413 or else Nkind
(Parent_Node
) = N_Simple_Return_Statement
))
3415 Set_Expansion_Delayed
(N
);
3419 -- Otherwise, if a transient scope is required, create it now. If we
3420 -- are within an initialization procedure do not create such, because
3421 -- the target of the assignment must not be declared within a local
3422 -- block, and because cleanup will take place on return from the
3423 -- initialization procedure.
3424 -- Should the condition be more restrictive ???
3426 if Requires_Transient_Scope
(Typ
) and then not Inside_Init_Proc
then
3427 Establish_Transient_Scope
(N
, Sec_Stack
=> Needs_Finalization
(Typ
));
3430 -- If the aggregate is non-limited, create a temporary. If it is limited
3431 -- and context is an assignment, this is a subaggregate for an enclosing
3432 -- aggregate being expanded. It must be built in place, so use target of
3433 -- the current assignment.
3435 if Is_Limited_Type
(Typ
)
3436 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
3438 Target_Expr
:= New_Copy_Tree
(Name
(Parent
(N
)));
3439 Insert_Actions
(Parent
(N
),
3440 Build_Record_Aggr_Code
(N
, Typ
, Target_Expr
));
3441 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
3444 Temp
:= Make_Temporary
(Loc
, 'A', N
);
3446 -- If the type inherits unknown discriminants, use the view with
3447 -- known discriminants if available.
3449 if Has_Unknown_Discriminants
(Typ
)
3450 and then Present
(Underlying_Record_View
(Typ
))
3452 T
:= Underlying_Record_View
(Typ
);
3458 Make_Object_Declaration
(Loc
,
3459 Defining_Identifier
=> Temp
,
3460 Object_Definition
=> New_Occurrence_Of
(T
, Loc
));
3462 Set_No_Initialization
(Instr
);
3463 Insert_Action
(N
, Instr
);
3464 Initialize_Discriminants
(Instr
, T
);
3466 Target_Expr
:= New_Occurrence_Of
(Temp
, Loc
);
3467 Aggr_Code
:= Build_Record_Aggr_Code
(N
, T
, Target_Expr
);
3469 -- Save the last assignment statement associated with the aggregate
3470 -- when building a controlled object. This reference is utilized by
3471 -- the finalization machinery when marking an object as successfully
3474 if Needs_Finalization
(T
) then
3475 Set_Last_Aggregate_Assignment
(Temp
, Last
(Aggr_Code
));
3478 Insert_Actions
(N
, Aggr_Code
);
3479 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
3480 Analyze_And_Resolve
(N
, T
);
3482 end Convert_To_Assignments
;
3484 ---------------------------
3485 -- Convert_To_Positional --
3486 ---------------------------
3488 procedure Convert_To_Positional
3490 Max_Others_Replicate
: Nat
:= 5;
3491 Handle_Bit_Packed
: Boolean := False)
3493 Typ
: constant Entity_Id
:= Etype
(N
);
3495 Static_Components
: Boolean := True;
3497 procedure Check_Static_Components
;
3498 -- Check whether all components of the aggregate are compile-time known
3499 -- values, and can be passed as is to the back-end without further
3505 Ixb
: Node_Id
) return Boolean;
3506 -- Convert the aggregate into a purely positional form if possible. On
3507 -- entry the bounds of all dimensions are known to be static, and the
3508 -- total number of components is safe enough to expand.
3510 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean;
3511 -- Return True iff the array N is flat (which is not trivial in the case
3512 -- of multidimensional aggregates).
3514 -----------------------------
3515 -- Check_Static_Components --
3516 -----------------------------
3518 -- Could use some comments in this body ???
3520 procedure Check_Static_Components
is
3524 Static_Components
:= True;
3526 if Nkind
(N
) = N_String_Literal
then
3529 elsif Present
(Expressions
(N
)) then
3530 Expr
:= First
(Expressions
(N
));
3531 while Present
(Expr
) loop
3532 if Nkind
(Expr
) /= N_Aggregate
3533 or else not Compile_Time_Known_Aggregate
(Expr
)
3534 or else Expansion_Delayed
(Expr
)
3536 Static_Components
:= False;
3544 if Nkind
(N
) = N_Aggregate
3545 and then Present
(Component_Associations
(N
))
3547 Expr
:= First
(Component_Associations
(N
));
3548 while Present
(Expr
) loop
3549 if Nkind_In
(Expression
(Expr
), N_Integer_Literal
,
3554 elsif Is_Entity_Name
(Expression
(Expr
))
3555 and then Present
(Entity
(Expression
(Expr
)))
3556 and then Ekind
(Entity
(Expression
(Expr
))) =
3557 E_Enumeration_Literal
3561 elsif Nkind
(Expression
(Expr
)) /= N_Aggregate
3562 or else not Compile_Time_Known_Aggregate
(Expression
(Expr
))
3563 or else Expansion_Delayed
(Expression
(Expr
))
3565 Static_Components
:= False;
3572 end Check_Static_Components
;
3581 Ixb
: Node_Id
) return Boolean
3583 Loc
: constant Source_Ptr
:= Sloc
(N
);
3584 Blo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ixb
));
3585 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ix
));
3586 Hi
: constant Node_Id
:= Type_High_Bound
(Etype
(Ix
));
3590 Others_Present
: Boolean := False;
3593 if Nkind
(Original_Node
(N
)) = N_String_Literal
then
3597 if not Compile_Time_Known_Value
(Lo
)
3598 or else not Compile_Time_Known_Value
(Hi
)
3603 Lov
:= Expr_Value
(Lo
);
3604 Hiv
:= Expr_Value
(Hi
);
3606 -- Check if there is an others choice
3608 if Present
(Component_Associations
(N
)) then
3614 Assoc
:= First
(Component_Associations
(N
));
3615 while Present
(Assoc
) loop
3617 -- If this is a box association, flattening is in general
3618 -- not possible because at this point we cannot tell if the
3619 -- default is static or even exists.
3621 if Box_Present
(Assoc
) then
3625 Choice
:= First
(Choices
(Assoc
));
3627 while Present
(Choice
) loop
3628 if Nkind
(Choice
) = N_Others_Choice
then
3629 Others_Present
:= True;
3640 -- If the low bound is not known at compile time and others is not
3641 -- present we can proceed since the bounds can be obtained from the
3644 -- Note: This case is required in VM platforms since their backends
3645 -- normalize array indexes in the range 0 .. N-1. Hence, if we do
3646 -- not flat an array whose bounds cannot be obtained from the type
3647 -- of the index the backend has no way to properly generate the code.
3648 -- See ACATS c460010 for an example.
3651 or else (not Compile_Time_Known_Value
(Blo
) and then Others_Present
)
3656 -- Determine if set of alternatives is suitable for conversion and
3657 -- build an array containing the values in sequence.
3660 Vals
: array (UI_To_Int
(Lov
) .. UI_To_Int
(Hiv
))
3661 of Node_Id
:= (others => Empty
);
3662 -- The values in the aggregate sorted appropriately
3665 -- Same data as Vals in list form
3668 -- Used to validate Max_Others_Replicate limit
3671 Num
: Int
:= UI_To_Int
(Lov
);
3677 if Present
(Expressions
(N
)) then
3678 Elmt
:= First
(Expressions
(N
));
3679 while Present
(Elmt
) loop
3680 if Nkind
(Elmt
) = N_Aggregate
3681 and then Present
(Next_Index
(Ix
))
3683 not Flatten
(Elmt
, Next_Index
(Ix
), Next_Index
(Ixb
))
3688 Vals
(Num
) := Relocate_Node
(Elmt
);
3695 if No
(Component_Associations
(N
)) then
3699 Elmt
:= First
(Component_Associations
(N
));
3701 if Nkind
(Expression
(Elmt
)) = N_Aggregate
then
3702 if Present
(Next_Index
(Ix
))
3705 (Expression
(Elmt
), Next_Index
(Ix
), Next_Index
(Ixb
))
3711 Component_Loop
: while Present
(Elmt
) loop
3712 Choice
:= First
(Choices
(Elmt
));
3713 Choice_Loop
: while Present
(Choice
) loop
3715 -- If we have an others choice, fill in the missing elements
3716 -- subject to the limit established by Max_Others_Replicate.
3718 if Nkind
(Choice
) = N_Others_Choice
then
3721 for J
in Vals
'Range loop
3722 if No
(Vals
(J
)) then
3723 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
3724 Rep_Count
:= Rep_Count
+ 1;
3726 -- Check for maximum others replication. Note that
3727 -- we skip this test if either of the restrictions
3728 -- No_Elaboration_Code or No_Implicit_Loops is
3729 -- active, if this is a preelaborable unit or
3730 -- a predefined unit, or if the unit must be
3731 -- placed in data memory. This also ensures that
3732 -- predefined units get the same level of constant
3733 -- folding in Ada 95 and Ada 2005, where their
3734 -- categorization has changed.
3737 P
: constant Entity_Id
:=
3738 Cunit_Entity
(Current_Sem_Unit
);
3741 -- Check if duplication OK and if so continue
3744 if Restriction_Active
(No_Elaboration_Code
)
3745 or else Restriction_Active
(No_Implicit_Loops
)
3747 (Ekind
(Current_Scope
) = E_Package
3748 and then Static_Elaboration_Desired
3750 or else Is_Preelaborated
(P
)
3751 or else (Ekind
(P
) = E_Package_Body
3753 Is_Preelaborated
(Spec_Entity
(P
)))
3755 Is_Predefined_File_Name
3756 (Unit_File_Name
(Get_Source_Unit
(P
)))
3760 -- If duplication not OK, then we return False
3761 -- if the replication count is too high
3763 elsif Rep_Count
> Max_Others_Replicate
then
3766 -- Continue on if duplication not OK, but the
3767 -- replication count is not excessive.
3776 exit Component_Loop
;
3778 -- Case of a subtype mark, identifier or expanded name
3780 elsif Is_Entity_Name
(Choice
)
3781 and then Is_Type
(Entity
(Choice
))
3783 Lo
:= Type_Low_Bound
(Etype
(Choice
));
3784 Hi
:= Type_High_Bound
(Etype
(Choice
));
3786 -- Case of subtype indication
3788 elsif Nkind
(Choice
) = N_Subtype_Indication
then
3789 Lo
:= Low_Bound
(Range_Expression
(Constraint
(Choice
)));
3790 Hi
:= High_Bound
(Range_Expression
(Constraint
(Choice
)));
3794 elsif Nkind
(Choice
) = N_Range
then
3795 Lo
:= Low_Bound
(Choice
);
3796 Hi
:= High_Bound
(Choice
);
3798 -- Normal subexpression case
3800 else pragma Assert
(Nkind
(Choice
) in N_Subexpr
);
3801 if not Compile_Time_Known_Value
(Choice
) then
3805 Choice_Index
:= UI_To_Int
(Expr_Value
(Choice
));
3807 if Choice_Index
in Vals
'Range then
3808 Vals
(Choice_Index
) :=
3809 New_Copy_Tree
(Expression
(Elmt
));
3812 -- Choice is statically out-of-range, will be
3813 -- rewritten to raise Constraint_Error.
3821 -- Range cases merge with Lo,Hi set
3823 if not Compile_Time_Known_Value
(Lo
)
3825 not Compile_Time_Known_Value
(Hi
)
3830 for J
in UI_To_Int
(Expr_Value
(Lo
)) ..
3831 UI_To_Int
(Expr_Value
(Hi
))
3833 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
3839 end loop Choice_Loop
;
3842 end loop Component_Loop
;
3844 -- If we get here the conversion is possible
3847 for J
in Vals
'Range loop
3848 Append
(Vals
(J
), Vlist
);
3851 Rewrite
(N
, Make_Aggregate
(Loc
, Expressions
=> Vlist
));
3852 Set_Aggregate_Bounds
(N
, Aggregate_Bounds
(Original_Node
(N
)));
3861 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean is
3868 elsif Nkind
(N
) = N_Aggregate
then
3869 if Present
(Component_Associations
(N
)) then
3873 Elmt
:= First
(Expressions
(N
));
3874 while Present
(Elmt
) loop
3875 if not Is_Flat
(Elmt
, Dims
- 1) then
3889 -- Start of processing for Convert_To_Positional
3892 -- Ada 2005 (AI-287): Do not convert in case of default initialized
3893 -- components because in this case will need to call the corresponding
3896 if Has_Default_Init_Comps
(N
) then
3900 if Is_Flat
(N
, Number_Dimensions
(Typ
)) then
3904 if Is_Bit_Packed_Array
(Typ
) and then not Handle_Bit_Packed
then
3908 -- Do not convert to positional if controlled components are involved
3909 -- since these require special processing
3911 if Has_Controlled_Component
(Typ
) then
3915 Check_Static_Components
;
3917 -- If the size is known, or all the components are static, try to
3918 -- build a fully positional aggregate.
3920 -- The size of the type may not be known for an aggregate with
3921 -- discriminated array components, but if the components are static
3922 -- it is still possible to verify statically that the length is
3923 -- compatible with the upper bound of the type, and therefore it is
3924 -- worth flattening such aggregates as well.
3926 -- For now the back-end expands these aggregates into individual
3927 -- assignments to the target anyway, but it is conceivable that
3928 -- it will eventually be able to treat such aggregates statically???
3930 if Aggr_Size_OK
(N
, Typ
)
3931 and then Flatten
(N
, First_Index
(Typ
), First_Index
(Base_Type
(Typ
)))
3933 if Static_Components
then
3934 Set_Compile_Time_Known_Aggregate
(N
);
3935 Set_Expansion_Delayed
(N
, False);
3938 Analyze_And_Resolve
(N
, Typ
);
3941 -- Is Static_Eaboration_Desired has been specified, diagnose aggregates
3942 -- that will still require initialization code.
3944 if (Ekind
(Current_Scope
) = E_Package
3945 and then Static_Elaboration_Desired
(Current_Scope
))
3946 and then Nkind
(Parent
(N
)) = N_Object_Declaration
3952 if Nkind
(N
) = N_Aggregate
and then Present
(Expressions
(N
)) then
3953 Expr
:= First
(Expressions
(N
));
3954 while Present
(Expr
) loop
3955 if Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
)
3957 (Is_Entity_Name
(Expr
)
3958 and then Ekind
(Entity
(Expr
)) = E_Enumeration_Literal
)
3964 ("non-static object requires elaboration code??", N
);
3971 if Present
(Component_Associations
(N
)) then
3972 Error_Msg_N
("object requires elaboration code??", N
);
3977 end Convert_To_Positional
;
3979 ----------------------------
3980 -- Expand_Array_Aggregate --
3981 ----------------------------
3983 -- Array aggregate expansion proceeds as follows:
3985 -- 1. If requested we generate code to perform all the array aggregate
3986 -- bound checks, specifically
3988 -- (a) Check that the index range defined by aggregate bounds is
3989 -- compatible with corresponding index subtype.
3991 -- (b) If an others choice is present check that no aggregate
3992 -- index is outside the bounds of the index constraint.
3994 -- (c) For multidimensional arrays make sure that all subaggregates
3995 -- corresponding to the same dimension have the same bounds.
3997 -- 2. Check for packed array aggregate which can be converted to a
3998 -- constant so that the aggregate disappears completely.
4000 -- 3. Check case of nested aggregate. Generally nested aggregates are
4001 -- handled during the processing of the parent aggregate.
4003 -- 4. Check if the aggregate can be statically processed. If this is the
4004 -- case pass it as is to Gigi. Note that a necessary condition for
4005 -- static processing is that the aggregate be fully positional.
4007 -- 5. If in place aggregate expansion is possible (i.e. no need to create
4008 -- a temporary) then mark the aggregate as such and return. Otherwise
4009 -- create a new temporary and generate the appropriate initialization
4012 procedure Expand_Array_Aggregate
(N
: Node_Id
) is
4013 Loc
: constant Source_Ptr
:= Sloc
(N
);
4015 Typ
: constant Entity_Id
:= Etype
(N
);
4016 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
4017 -- Typ is the correct constrained array subtype of the aggregate
4018 -- Ctyp is the corresponding component type.
4020 Aggr_Dimension
: constant Pos
:= Number_Dimensions
(Typ
);
4021 -- Number of aggregate index dimensions
4023 Aggr_Low
: array (1 .. Aggr_Dimension
) of Node_Id
;
4024 Aggr_High
: array (1 .. Aggr_Dimension
) of Node_Id
;
4025 -- Low and High bounds of the constraint for each aggregate index
4027 Aggr_Index_Typ
: array (1 .. Aggr_Dimension
) of Entity_Id
;
4028 -- The type of each index
4030 In_Place_Assign_OK_For_Declaration
: Boolean := False;
4031 -- True if we are to generate an in place assignment for a declaration
4033 Maybe_In_Place_OK
: Boolean;
4034 -- If the type is neither controlled nor packed and the aggregate
4035 -- is the expression in an assignment, assignment in place may be
4036 -- possible, provided other conditions are met on the LHS.
4038 Others_Present
: array (1 .. Aggr_Dimension
) of Boolean :=
4040 -- If Others_Present (J) is True, then there is an others choice
4041 -- in one of the sub-aggregates of N at dimension J.
4043 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean;
4044 -- Returns true if an aggregate assignment can be done by the back end
4046 procedure Build_Constrained_Type
(Positional
: Boolean);
4047 -- If the subtype is not static or unconstrained, build a constrained
4048 -- type using the computable sizes of the aggregate and its sub-
4051 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
);
4052 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
4055 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4056 -- Checks that in a multi-dimensional array aggregate all subaggregates
4057 -- corresponding to the same dimension have the same bounds.
4058 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4059 -- corresponding to the sub-aggregate.
4061 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4062 -- Computes the values of array Others_Present. Sub_Aggr is the
4063 -- array sub-aggregate we start the computation from. Dim is the
4064 -- dimension corresponding to the sub-aggregate.
4066 function In_Place_Assign_OK
return Boolean;
4067 -- Simple predicate to determine whether an aggregate assignment can
4068 -- be done in place, because none of the new values can depend on the
4069 -- components of the target of the assignment.
4071 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4072 -- Checks that if an others choice is present in any sub-aggregate no
4073 -- aggregate index is outside the bounds of the index constraint.
4074 -- Sub_Aggr is an array sub-aggregate. Dim is the dimension
4075 -- corresponding to the sub-aggregate.
4077 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean;
4078 -- In addition to Maybe_In_Place_OK, in order for an aggregate to be
4079 -- built directly into the target of the assignment it must be free
4082 ------------------------------------
4083 -- Aggr_Assignment_OK_For_Backend --
4084 ------------------------------------
4086 -- Backend processing by Gigi/gcc is possible only if all the following
4087 -- conditions are met:
4089 -- 1. N consists of a single OTHERS choice, possibly recursively
4091 -- 2. The array type is not packed
4093 -- 3. The array type has no atomic components
4095 -- 4. The array type has no null ranges (the purpose of this is to
4096 -- avoid a bogus warning for an out-of-range value).
4098 -- 5. The component type is discrete
4100 -- 6. The component size is Storage_Unit or the value is of the form
4101 -- M * (1 + A**1 + A**2 + .. A**(K-1)) where A = 2**(Storage_Unit)
4102 -- and M in 1 .. A-1. This can also be viewed as K occurrences of
4103 -- the 8-bit value M, concatenated together.
4105 -- The ultimate goal is to generate a call to a fast memset routine
4106 -- specifically optimized for the target.
4108 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean is
4111 Expr
: Node_Id
:= N
;
4119 -- Recurse as far as possible to find the innermost component type
4122 while Is_Array_Type
(Ctyp
) loop
4123 if Nkind
(Expr
) /= N_Aggregate
4124 or else not Is_Others_Aggregate
(Expr
)
4129 if Present
(Packed_Array_Impl_Type
(Ctyp
)) then
4133 if Has_Atomic_Components
(Ctyp
) then
4137 Index
:= First_Index
(Ctyp
);
4138 while Present
(Index
) loop
4139 Get_Index_Bounds
(Index
, Low
, High
);
4141 if Is_Null_Range
(Low
, High
) then
4148 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4150 for J
in 1 .. Number_Dimensions
(Ctyp
) - 1 loop
4151 if Nkind
(Expr
) /= N_Aggregate
4152 or else not Is_Others_Aggregate
(Expr
)
4157 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4160 Ctyp
:= Component_Type
(Ctyp
);
4162 if Is_Atomic
(Ctyp
) then
4167 if not Is_Discrete_Type
(Ctyp
) then
4171 -- The expression needs to be analyzed if True is returned
4173 Analyze_And_Resolve
(Expr
, Ctyp
);
4175 -- The back end uses the Esize as the precision of the type
4177 Nunits
:= UI_To_Int
(Esize
(Ctyp
)) / System_Storage_Unit
;
4183 if not Compile_Time_Known_Value
(Expr
) then
4187 Value
:= Expr_Value
(Expr
);
4189 if Has_Biased_Representation
(Ctyp
) then
4190 Value
:= Value
- Expr_Value
(Type_Low_Bound
(Ctyp
));
4193 -- Values 0 and -1 immediately satisfy the last check
4195 if Value
= Uint_0
or else Value
= Uint_Minus_1
then
4199 -- We need to work with an unsigned value
4202 Value
:= Value
+ 2**(System_Storage_Unit
* Nunits
);
4205 Remainder
:= Value
rem 2**System_Storage_Unit
;
4207 for J
in 1 .. Nunits
- 1 loop
4208 Value
:= Value
/ 2**System_Storage_Unit
;
4210 if Value
rem 2**System_Storage_Unit
/= Remainder
then
4216 end Aggr_Assignment_OK_For_Backend
;
4218 ----------------------------
4219 -- Build_Constrained_Type --
4220 ----------------------------
4222 procedure Build_Constrained_Type
(Positional
: Boolean) is
4223 Loc
: constant Source_Ptr
:= Sloc
(N
);
4224 Agg_Type
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
4227 Typ
: constant Entity_Id
:= Etype
(N
);
4228 Indexes
: constant List_Id
:= New_List
;
4233 -- If the aggregate is purely positional, all its subaggregates
4234 -- have the same size. We collect the dimensions from the first
4235 -- subaggregate at each level.
4240 for D
in 1 .. Number_Dimensions
(Typ
) loop
4241 Sub_Agg
:= First
(Expressions
(Sub_Agg
));
4245 while Present
(Comp
) loop
4252 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
4253 High_Bound
=> Make_Integer_Literal
(Loc
, Num
)));
4257 -- We know the aggregate type is unconstrained and the aggregate
4258 -- is not processable by the back end, therefore not necessarily
4259 -- positional. Retrieve each dimension bounds (computed earlier).
4261 for D
in 1 .. Number_Dimensions
(Typ
) loop
4264 Low_Bound
=> Aggr_Low
(D
),
4265 High_Bound
=> Aggr_High
(D
)));
4270 Make_Full_Type_Declaration
(Loc
,
4271 Defining_Identifier
=> Agg_Type
,
4273 Make_Constrained_Array_Definition
(Loc
,
4274 Discrete_Subtype_Definitions
=> Indexes
,
4275 Component_Definition
=>
4276 Make_Component_Definition
(Loc
,
4277 Aliased_Present
=> False,
4278 Subtype_Indication
=>
4279 New_Occurrence_Of
(Component_Type
(Typ
), Loc
))));
4281 Insert_Action
(N
, Decl
);
4283 Set_Etype
(N
, Agg_Type
);
4284 Set_Is_Itype
(Agg_Type
);
4285 Freeze_Itype
(Agg_Type
, N
);
4286 end Build_Constrained_Type
;
4292 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
) is
4299 Cond
: Node_Id
:= Empty
;
4302 Get_Index_Bounds
(Aggr_Bounds
, Aggr_Lo
, Aggr_Hi
);
4303 Get_Index_Bounds
(Index_Bounds
, Ind_Lo
, Ind_Hi
);
4305 -- Generate the following test:
4307 -- [constraint_error when
4308 -- Aggr_Lo <= Aggr_Hi and then
4309 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
4311 -- As an optimization try to see if some tests are trivially vacuous
4312 -- because we are comparing an expression against itself.
4314 if Aggr_Lo
= Ind_Lo
and then Aggr_Hi
= Ind_Hi
then
4317 elsif Aggr_Hi
= Ind_Hi
then
4320 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4321 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
));
4323 elsif Aggr_Lo
= Ind_Lo
then
4326 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
4327 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Hi
));
4334 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4335 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
)),
4339 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
4340 Right_Opnd
=> Duplicate_Subexpr
(Ind_Hi
)));
4343 if Present
(Cond
) then
4348 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4349 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
)),
4351 Right_Opnd
=> Cond
);
4353 Set_Analyzed
(Left_Opnd
(Left_Opnd
(Cond
)), False);
4354 Set_Analyzed
(Right_Opnd
(Left_Opnd
(Cond
)), False);
4356 Make_Raise_Constraint_Error
(Loc
,
4358 Reason
=> CE_Range_Check_Failed
));
4362 ----------------------------
4363 -- Check_Same_Aggr_Bounds --
4364 ----------------------------
4366 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4367 Sub_Lo
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(Sub_Aggr
));
4368 Sub_Hi
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(Sub_Aggr
));
4369 -- The bounds of this specific sub-aggregate
4371 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
4372 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
4373 -- The bounds of the aggregate for this dimension
4375 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
4376 -- The index type for this dimension.xxx
4378 Cond
: Node_Id
:= Empty
;
4383 -- If index checks are on generate the test
4385 -- [constraint_error when
4386 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
4388 -- As an optimization try to see if some tests are trivially vacuos
4389 -- because we are comparing an expression against itself. Also for
4390 -- the first dimension the test is trivially vacuous because there
4391 -- is just one aggregate for dimension 1.
4393 if Index_Checks_Suppressed
(Ind_Typ
) then
4396 elsif Dim
= 1 or else (Aggr_Lo
= Sub_Lo
and then Aggr_Hi
= Sub_Hi
)
4400 elsif Aggr_Hi
= Sub_Hi
then
4403 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4404 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
));
4406 elsif Aggr_Lo
= Sub_Lo
then
4409 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
4410 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Hi
));
4417 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
4418 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
)),
4422 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
4423 Right_Opnd
=> Duplicate_Subexpr
(Sub_Hi
)));
4426 if Present
(Cond
) then
4428 Make_Raise_Constraint_Error
(Loc
,
4430 Reason
=> CE_Length_Check_Failed
));
4433 -- Now look inside the sub-aggregate to see if there is more work
4435 if Dim
< Aggr_Dimension
then
4437 -- Process positional components
4439 if Present
(Expressions
(Sub_Aggr
)) then
4440 Expr
:= First
(Expressions
(Sub_Aggr
));
4441 while Present
(Expr
) loop
4442 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
4447 -- Process component associations
4449 if Present
(Component_Associations
(Sub_Aggr
)) then
4450 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4451 while Present
(Assoc
) loop
4452 Expr
:= Expression
(Assoc
);
4453 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
4458 end Check_Same_Aggr_Bounds
;
4460 ----------------------------
4461 -- Compute_Others_Present --
4462 ----------------------------
4464 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4469 if Present
(Component_Associations
(Sub_Aggr
)) then
4470 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
4472 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
then
4473 Others_Present
(Dim
) := True;
4477 -- Now look inside the sub-aggregate to see if there is more work
4479 if Dim
< Aggr_Dimension
then
4481 -- Process positional components
4483 if Present
(Expressions
(Sub_Aggr
)) then
4484 Expr
:= First
(Expressions
(Sub_Aggr
));
4485 while Present
(Expr
) loop
4486 Compute_Others_Present
(Expr
, Dim
+ 1);
4491 -- Process component associations
4493 if Present
(Component_Associations
(Sub_Aggr
)) then
4494 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4495 while Present
(Assoc
) loop
4496 Expr
:= Expression
(Assoc
);
4497 Compute_Others_Present
(Expr
, Dim
+ 1);
4502 end Compute_Others_Present
;
4504 ------------------------
4505 -- In_Place_Assign_OK --
4506 ------------------------
4508 function In_Place_Assign_OK
return Boolean is
4516 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean;
4517 -- Check recursively that each component of a (sub)aggregate does
4518 -- not depend on the variable being assigned to.
4520 function Safe_Component
(Expr
: Node_Id
) return Boolean;
4521 -- Verify that an expression cannot depend on the variable being
4522 -- assigned to. Room for improvement here (but less than before).
4524 --------------------
4525 -- Safe_Aggregate --
4526 --------------------
4528 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean is
4532 if Present
(Expressions
(Aggr
)) then
4533 Expr
:= First
(Expressions
(Aggr
));
4534 while Present
(Expr
) loop
4535 if Nkind
(Expr
) = N_Aggregate
then
4536 if not Safe_Aggregate
(Expr
) then
4540 elsif not Safe_Component
(Expr
) then
4548 if Present
(Component_Associations
(Aggr
)) then
4549 Expr
:= First
(Component_Associations
(Aggr
));
4550 while Present
(Expr
) loop
4551 if Nkind
(Expression
(Expr
)) = N_Aggregate
then
4552 if not Safe_Aggregate
(Expression
(Expr
)) then
4556 -- If association has a box, no way to determine yet
4557 -- whether default can be assigned in place.
4559 elsif Box_Present
(Expr
) then
4562 elsif not Safe_Component
(Expression
(Expr
)) then
4573 --------------------
4574 -- Safe_Component --
4575 --------------------
4577 function Safe_Component
(Expr
: Node_Id
) return Boolean is
4578 Comp
: Node_Id
:= Expr
;
4580 function Check_Component
(Comp
: Node_Id
) return Boolean;
4581 -- Do the recursive traversal, after copy
4583 ---------------------
4584 -- Check_Component --
4585 ---------------------
4587 function Check_Component
(Comp
: Node_Id
) return Boolean is
4589 if Is_Overloaded
(Comp
) then
4593 return Compile_Time_Known_Value
(Comp
)
4595 or else (Is_Entity_Name
(Comp
)
4596 and then Present
(Entity
(Comp
))
4597 and then No
(Renamed_Object
(Entity
(Comp
))))
4599 or else (Nkind
(Comp
) = N_Attribute_Reference
4600 and then Check_Component
(Prefix
(Comp
)))
4602 or else (Nkind
(Comp
) in N_Binary_Op
4603 and then Check_Component
(Left_Opnd
(Comp
))
4604 and then Check_Component
(Right_Opnd
(Comp
)))
4606 or else (Nkind
(Comp
) in N_Unary_Op
4607 and then Check_Component
(Right_Opnd
(Comp
)))
4609 or else (Nkind
(Comp
) = N_Selected_Component
4610 and then Check_Component
(Prefix
(Comp
)))
4612 or else (Nkind
(Comp
) = N_Unchecked_Type_Conversion
4613 and then Check_Component
(Expression
(Comp
)));
4614 end Check_Component
;
4616 -- Start of processing for Safe_Component
4619 -- If the component appears in an association that may correspond
4620 -- to more than one element, it is not analyzed before expansion
4621 -- into assignments, to avoid side effects. We analyze, but do not
4622 -- resolve the copy, to obtain sufficient entity information for
4623 -- the checks that follow. If component is overloaded we assume
4624 -- an unsafe function call.
4626 if not Analyzed
(Comp
) then
4627 if Is_Overloaded
(Expr
) then
4630 elsif Nkind
(Expr
) = N_Aggregate
4631 and then not Is_Others_Aggregate
(Expr
)
4635 elsif Nkind
(Expr
) = N_Allocator
then
4637 -- For now, too complex to analyze
4642 Comp
:= New_Copy_Tree
(Expr
);
4643 Set_Parent
(Comp
, Parent
(Expr
));
4647 if Nkind
(Comp
) = N_Aggregate
then
4648 return Safe_Aggregate
(Comp
);
4650 return Check_Component
(Comp
);
4654 -- Start of processing for In_Place_Assign_OK
4657 if Present
(Component_Associations
(N
)) then
4659 -- On assignment, sliding can take place, so we cannot do the
4660 -- assignment in place unless the bounds of the aggregate are
4661 -- statically equal to those of the target.
4663 -- If the aggregate is given by an others choice, the bounds are
4664 -- derived from the left-hand side, and the assignment is safe if
4665 -- the expression is.
4667 if Is_Others_Aggregate
(N
) then
4670 (Expression
(First
(Component_Associations
(N
))));
4673 Aggr_In
:= First_Index
(Etype
(N
));
4675 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
4676 Obj_In
:= First_Index
(Etype
(Name
(Parent
(N
))));
4679 -- Context is an allocator. Check bounds of aggregate against
4680 -- given type in qualified expression.
4682 pragma Assert
(Nkind
(Parent
(Parent
(N
))) = N_Allocator
);
4684 First_Index
(Etype
(Entity
(Subtype_Mark
(Parent
(N
)))));
4687 while Present
(Aggr_In
) loop
4688 Get_Index_Bounds
(Aggr_In
, Aggr_Lo
, Aggr_Hi
);
4689 Get_Index_Bounds
(Obj_In
, Obj_Lo
, Obj_Hi
);
4691 if not Compile_Time_Known_Value
(Aggr_Lo
)
4692 or else not Compile_Time_Known_Value
(Aggr_Hi
)
4693 or else not Compile_Time_Known_Value
(Obj_Lo
)
4694 or else not Compile_Time_Known_Value
(Obj_Hi
)
4695 or else Expr_Value
(Aggr_Lo
) /= Expr_Value
(Obj_Lo
)
4696 or else Expr_Value
(Aggr_Hi
) /= Expr_Value
(Obj_Hi
)
4701 Next_Index
(Aggr_In
);
4702 Next_Index
(Obj_In
);
4706 -- Now check the component values themselves
4708 return Safe_Aggregate
(N
);
4709 end In_Place_Assign_OK
;
4715 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
4716 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
4717 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
4718 -- The bounds of the aggregate for this dimension
4720 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
4721 -- The index type for this dimension
4723 Need_To_Check
: Boolean := False;
4725 Choices_Lo
: Node_Id
:= Empty
;
4726 Choices_Hi
: Node_Id
:= Empty
;
4727 -- The lowest and highest discrete choices for a named sub-aggregate
4729 Nb_Choices
: Int
:= -1;
4730 -- The number of discrete non-others choices in this sub-aggregate
4732 Nb_Elements
: Uint
:= Uint_0
;
4733 -- The number of elements in a positional aggregate
4735 Cond
: Node_Id
:= Empty
;
4742 -- Check if we have an others choice. If we do make sure that this
4743 -- sub-aggregate contains at least one element in addition to the
4746 if Range_Checks_Suppressed
(Ind_Typ
) then
4747 Need_To_Check
:= False;
4749 elsif Present
(Expressions
(Sub_Aggr
))
4750 and then Present
(Component_Associations
(Sub_Aggr
))
4752 Need_To_Check
:= True;
4754 elsif Present
(Component_Associations
(Sub_Aggr
)) then
4755 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
4757 if Nkind
(First
(Choices
(Assoc
))) /= N_Others_Choice
then
4758 Need_To_Check
:= False;
4761 -- Count the number of discrete choices. Start with -1 because
4762 -- the others choice does not count.
4764 -- Is there some reason we do not use List_Length here ???
4767 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4768 while Present
(Assoc
) loop
4769 Choice
:= First
(Choices
(Assoc
));
4770 while Present
(Choice
) loop
4771 Nb_Choices
:= Nb_Choices
+ 1;
4778 -- If there is only an others choice nothing to do
4780 Need_To_Check
:= (Nb_Choices
> 0);
4784 Need_To_Check
:= False;
4787 -- If we are dealing with a positional sub-aggregate with an others
4788 -- choice then compute the number or positional elements.
4790 if Need_To_Check
and then Present
(Expressions
(Sub_Aggr
)) then
4791 Expr
:= First
(Expressions
(Sub_Aggr
));
4792 Nb_Elements
:= Uint_0
;
4793 while Present
(Expr
) loop
4794 Nb_Elements
:= Nb_Elements
+ 1;
4798 -- If the aggregate contains discrete choices and an others choice
4799 -- compute the smallest and largest discrete choice values.
4801 elsif Need_To_Check
then
4802 Compute_Choices_Lo_And_Choices_Hi
: declare
4804 Table
: Case_Table_Type
(1 .. Nb_Choices
);
4805 -- Used to sort all the different choice values
4812 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4813 while Present
(Assoc
) loop
4814 Choice
:= First
(Choices
(Assoc
));
4815 while Present
(Choice
) loop
4816 if Nkind
(Choice
) = N_Others_Choice
then
4820 Get_Index_Bounds
(Choice
, Low
, High
);
4821 Table
(J
).Choice_Lo
:= Low
;
4822 Table
(J
).Choice_Hi
:= High
;
4831 -- Sort the discrete choices
4833 Sort_Case_Table
(Table
);
4835 Choices_Lo
:= Table
(1).Choice_Lo
;
4836 Choices_Hi
:= Table
(Nb_Choices
).Choice_Hi
;
4837 end Compute_Choices_Lo_And_Choices_Hi
;
4840 -- If no others choice in this sub-aggregate, or the aggregate
4841 -- comprises only an others choice, nothing to do.
4843 if not Need_To_Check
then
4846 -- If we are dealing with an aggregate containing an others choice
4847 -- and positional components, we generate the following test:
4849 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
4850 -- Ind_Typ'Pos (Aggr_Hi)
4852 -- raise Constraint_Error;
4855 elsif Nb_Elements
> Uint_0
then
4861 Make_Attribute_Reference
(Loc
,
4862 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
4863 Attribute_Name
=> Name_Pos
,
4866 (Duplicate_Subexpr_Move_Checks
(Aggr_Lo
))),
4867 Right_Opnd
=> Make_Integer_Literal
(Loc
, Nb_Elements
- 1)),
4870 Make_Attribute_Reference
(Loc
,
4871 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
4872 Attribute_Name
=> Name_Pos
,
4873 Expressions
=> New_List
(
4874 Duplicate_Subexpr_Move_Checks
(Aggr_Hi
))));
4876 -- If we are dealing with an aggregate containing an others choice
4877 -- and discrete choices we generate the following test:
4879 -- [constraint_error when
4880 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
4887 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Choices_Lo
),
4888 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
)),
4892 Left_Opnd
=> Duplicate_Subexpr
(Choices_Hi
),
4893 Right_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
)));
4896 if Present
(Cond
) then
4898 Make_Raise_Constraint_Error
(Loc
,
4900 Reason
=> CE_Length_Check_Failed
));
4901 -- Questionable reason code, shouldn't that be a
4902 -- CE_Range_Check_Failed ???
4905 -- Now look inside the sub-aggregate to see if there is more work
4907 if Dim
< Aggr_Dimension
then
4909 -- Process positional components
4911 if Present
(Expressions
(Sub_Aggr
)) then
4912 Expr
:= First
(Expressions
(Sub_Aggr
));
4913 while Present
(Expr
) loop
4914 Others_Check
(Expr
, Dim
+ 1);
4919 -- Process component associations
4921 if Present
(Component_Associations
(Sub_Aggr
)) then
4922 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
4923 while Present
(Assoc
) loop
4924 Expr
:= Expression
(Assoc
);
4925 Others_Check
(Expr
, Dim
+ 1);
4932 -------------------------
4933 -- Safe_Left_Hand_Side --
4934 -------------------------
4936 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean is
4937 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean;
4938 -- If the left-hand side includes an indexed component, check that
4939 -- the indexes are free of side-effect.
4945 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean is
4947 if Is_Entity_Name
(Indx
) then
4950 elsif Nkind
(Indx
) = N_Integer_Literal
then
4953 elsif Nkind
(Indx
) = N_Function_Call
4954 and then Is_Entity_Name
(Name
(Indx
))
4955 and then Has_Pragma_Pure_Function
(Entity
(Name
(Indx
)))
4959 elsif Nkind
(Indx
) = N_Type_Conversion
4960 and then Is_Safe_Index
(Expression
(Indx
))
4969 -- Start of processing for Safe_Left_Hand_Side
4972 if Is_Entity_Name
(N
) then
4975 elsif Nkind_In
(N
, N_Explicit_Dereference
, N_Selected_Component
)
4976 and then Safe_Left_Hand_Side
(Prefix
(N
))
4980 elsif Nkind
(N
) = N_Indexed_Component
4981 and then Safe_Left_Hand_Side
(Prefix
(N
))
4982 and then Is_Safe_Index
(First
(Expressions
(N
)))
4986 elsif Nkind
(N
) = N_Unchecked_Type_Conversion
then
4987 return Safe_Left_Hand_Side
(Expression
(N
));
4992 end Safe_Left_Hand_Side
;
4997 -- Holds the temporary aggregate value
5000 -- Holds the declaration of Tmp
5002 Aggr_Code
: List_Id
;
5003 Parent_Node
: Node_Id
;
5004 Parent_Kind
: Node_Kind
;
5006 -- Start of processing for Expand_Array_Aggregate
5009 -- Do not touch the special aggregates of attributes used for Asm calls
5011 if Is_RTE
(Ctyp
, RE_Asm_Input_Operand
)
5012 or else Is_RTE
(Ctyp
, RE_Asm_Output_Operand
)
5016 -- Do not expand an aggregate for an array type which contains tasks if
5017 -- the aggregate is associated with an unexpanded return statement of a
5018 -- build-in-place function. The aggregate is expanded when the related
5019 -- return statement (rewritten into an extended return) is processed.
5020 -- This delay ensures that any temporaries and initialization code
5021 -- generated for the aggregate appear in the proper return block and
5022 -- use the correct _chain and _master.
5024 elsif Has_Task
(Base_Type
(Etype
(N
)))
5025 and then Nkind
(Parent
(N
)) = N_Simple_Return_Statement
5026 and then Is_Build_In_Place_Function
5027 (Return_Applies_To
(Return_Statement_Entity
(Parent
(N
))))
5031 -- Do not attempt expansion if error already detected. We may reach this
5032 -- point in spite of previous errors when compiling with -gnatq, to
5033 -- force all possible errors (this is the usual ACATS mode).
5035 elsif Error_Posted
(N
) then
5039 -- If the semantic analyzer has determined that aggregate N will raise
5040 -- Constraint_Error at run time, then the aggregate node has been
5041 -- replaced with an N_Raise_Constraint_Error node and we should
5044 pragma Assert
(not Raises_Constraint_Error
(N
));
5048 -- Check that the index range defined by aggregate bounds is
5049 -- compatible with corresponding index subtype.
5051 Index_Compatibility_Check
: declare
5052 Aggr_Index_Range
: Node_Id
:= First_Index
(Typ
);
5053 -- The current aggregate index range
5055 Index_Constraint
: Node_Id
:= First_Index
(Etype
(Typ
));
5056 -- The corresponding index constraint against which we have to
5057 -- check the above aggregate index range.
5060 Compute_Others_Present
(N
, 1);
5062 for J
in 1 .. Aggr_Dimension
loop
5063 -- There is no need to emit a check if an others choice is present
5064 -- for this array aggregate dimension since in this case one of
5065 -- N's sub-aggregates has taken its bounds from the context and
5066 -- these bounds must have been checked already. In addition all
5067 -- sub-aggregates corresponding to the same dimension must all
5068 -- have the same bounds (checked in (c) below).
5070 if not Range_Checks_Suppressed
(Etype
(Index_Constraint
))
5071 and then not Others_Present
(J
)
5073 -- We don't use Checks.Apply_Range_Check here because it emits
5074 -- a spurious check. Namely it checks that the range defined by
5075 -- the aggregate bounds is non empty. But we know this already
5078 Check_Bounds
(Aggr_Index_Range
, Index_Constraint
);
5081 -- Save the low and high bounds of the aggregate index as well as
5082 -- the index type for later use in checks (b) and (c) below.
5084 Aggr_Low
(J
) := Low_Bound
(Aggr_Index_Range
);
5085 Aggr_High
(J
) := High_Bound
(Aggr_Index_Range
);
5087 Aggr_Index_Typ
(J
) := Etype
(Index_Constraint
);
5089 Next_Index
(Aggr_Index_Range
);
5090 Next_Index
(Index_Constraint
);
5092 end Index_Compatibility_Check
;
5096 -- If an others choice is present check that no aggregate index is
5097 -- outside the bounds of the index constraint.
5099 Others_Check
(N
, 1);
5103 -- For multidimensional arrays make sure that all subaggregates
5104 -- corresponding to the same dimension have the same bounds.
5106 if Aggr_Dimension
> 1 then
5107 Check_Same_Aggr_Bounds
(N
, 1);
5112 -- If we have a default component value, or simple initialization is
5113 -- required for the component type, then we replace <> in component
5114 -- associations by the required default value.
5117 Default_Val
: Node_Id
;
5121 if (Present
(Default_Aspect_Component_Value
(Typ
))
5122 or else Needs_Simple_Initialization
(Ctyp
))
5123 and then Present
(Component_Associations
(N
))
5125 Assoc
:= First
(Component_Associations
(N
));
5126 while Present
(Assoc
) loop
5127 if Nkind
(Assoc
) = N_Component_Association
5128 and then Box_Present
(Assoc
)
5130 Set_Box_Present
(Assoc
, False);
5132 if Present
(Default_Aspect_Component_Value
(Typ
)) then
5133 Default_Val
:= Default_Aspect_Component_Value
(Typ
);
5135 Default_Val
:= Get_Simple_Init_Val
(Ctyp
, N
);
5138 Set_Expression
(Assoc
, New_Copy_Tree
(Default_Val
));
5139 Analyze_And_Resolve
(Expression
(Assoc
), Ctyp
);
5149 -- Here we test for is packed array aggregate that we can handle at
5150 -- compile time. If so, return with transformation done. Note that we do
5151 -- this even if the aggregate is nested, because once we have done this
5152 -- processing, there is no more nested aggregate.
5154 if Packed_Array_Aggregate_Handled
(N
) then
5158 -- At this point we try to convert to positional form
5160 if Ekind
(Current_Scope
) = E_Package
5161 and then Static_Elaboration_Desired
(Current_Scope
)
5163 Convert_To_Positional
(N
, Max_Others_Replicate
=> 100);
5165 Convert_To_Positional
(N
);
5168 -- if the result is no longer an aggregate (e.g. it may be a string
5169 -- literal, or a temporary which has the needed value), then we are
5170 -- done, since there is no longer a nested aggregate.
5172 if Nkind
(N
) /= N_Aggregate
then
5175 -- We are also done if the result is an analyzed aggregate, indicating
5176 -- that Convert_To_Positional succeeded and reanalyzed the rewritten
5179 elsif Analyzed
(N
) and then N
/= Original_Node
(N
) then
5183 -- If all aggregate components are compile-time known and the aggregate
5184 -- has been flattened, nothing left to do. The same occurs if the
5185 -- aggregate is used to initialize the components of a statically
5186 -- allocated dispatch table.
5188 if Compile_Time_Known_Aggregate
(N
)
5189 or else Is_Static_Dispatch_Table_Aggregate
(N
)
5191 Set_Expansion_Delayed
(N
, False);
5195 -- Now see if back end processing is possible
5197 if Backend_Processing_Possible
(N
) then
5199 -- If the aggregate is static but the constraints are not, build
5200 -- a static subtype for the aggregate, so that Gigi can place it
5201 -- in static memory. Perform an unchecked_conversion to the non-
5202 -- static type imposed by the context.
5205 Itype
: constant Entity_Id
:= Etype
(N
);
5207 Needs_Type
: Boolean := False;
5210 Index
:= First_Index
(Itype
);
5211 while Present
(Index
) loop
5212 if not Is_OK_Static_Subtype
(Etype
(Index
)) then
5221 Build_Constrained_Type
(Positional
=> True);
5222 Rewrite
(N
, Unchecked_Convert_To
(Itype
, N
));
5232 -- Delay expansion for nested aggregates: it will be taken care of
5233 -- when the parent aggregate is expanded.
5235 Parent_Node
:= Parent
(N
);
5236 Parent_Kind
:= Nkind
(Parent_Node
);
5238 if Parent_Kind
= N_Qualified_Expression
then
5239 Parent_Node
:= Parent
(Parent_Node
);
5240 Parent_Kind
:= Nkind
(Parent_Node
);
5243 if Parent_Kind
= N_Aggregate
5244 or else Parent_Kind
= N_Extension_Aggregate
5245 or else Parent_Kind
= N_Component_Association
5246 or else (Parent_Kind
= N_Object_Declaration
5247 and then Needs_Finalization
(Typ
))
5248 or else (Parent_Kind
= N_Assignment_Statement
5249 and then Inside_Init_Proc
)
5251 if Static_Array_Aggregate
(N
)
5252 or else Compile_Time_Known_Aggregate
(N
)
5254 Set_Expansion_Delayed
(N
, False);
5257 Set_Expansion_Delayed
(N
);
5264 -- Look if in place aggregate expansion is possible
5266 -- For object declarations we build the aggregate in place, unless
5267 -- the array is bit-packed or the component is controlled.
5269 -- For assignments we do the assignment in place if all the component
5270 -- associations have compile-time known values. For other cases we
5271 -- create a temporary. The analysis for safety of on-line assignment
5272 -- is delicate, i.e. we don't know how to do it fully yet ???
5274 -- For allocators we assign to the designated object in place if the
5275 -- aggregate meets the same conditions as other in-place assignments.
5276 -- In this case the aggregate may not come from source but was created
5277 -- for default initialization, e.g. with Initialize_Scalars.
5279 if Requires_Transient_Scope
(Typ
) then
5280 Establish_Transient_Scope
5281 (N
, Sec_Stack
=> Has_Controlled_Component
(Typ
));
5284 if Has_Default_Init_Comps
(N
) then
5285 Maybe_In_Place_OK
:= False;
5287 elsif Is_Bit_Packed_Array
(Typ
)
5288 or else Has_Controlled_Component
(Typ
)
5290 Maybe_In_Place_OK
:= False;
5293 Maybe_In_Place_OK
:=
5294 (Nkind
(Parent
(N
)) = N_Assignment_Statement
5295 and then In_Place_Assign_OK
)
5298 (Nkind
(Parent
(Parent
(N
))) = N_Allocator
5299 and then In_Place_Assign_OK
);
5302 -- If this is an array of tasks, it will be expanded into build-in-place
5303 -- assignments. Build an activation chain for the tasks now.
5305 if Has_Task
(Etype
(N
)) then
5306 Build_Activation_Chain_Entity
(N
);
5309 -- Perform in-place expansion of aggregate in an object declaration.
5310 -- Note: actions generated for the aggregate will be captured in an
5311 -- expression-with-actions statement so that they can be transferred
5312 -- to freeze actions later if there is an address clause for the
5313 -- object. (Note: we don't use a block statement because this would
5314 -- cause generated freeze nodes to be elaborated in the wrong scope).
5316 -- Should document these individual tests ???
5318 if not Has_Default_Init_Comps
(N
)
5319 and then Comes_From_Source
(Parent_Node
)
5320 and then Parent_Kind
= N_Object_Declaration
5322 Must_Slide
(Etype
(Defining_Identifier
(Parent_Node
)), Typ
)
5323 and then N
= Expression
(Parent_Node
)
5324 and then not Is_Bit_Packed_Array
(Typ
)
5325 and then not Has_Controlled_Component
(Typ
)
5327 In_Place_Assign_OK_For_Declaration
:= True;
5328 Tmp
:= Defining_Identifier
(Parent
(N
));
5329 Set_No_Initialization
(Parent
(N
));
5330 Set_Expression
(Parent
(N
), Empty
);
5332 -- Set kind and type of the entity, for use in the analysis
5333 -- of the subsequent assignments. If the nominal type is not
5334 -- constrained, build a subtype from the known bounds of the
5335 -- aggregate. If the declaration has a subtype mark, use it,
5336 -- otherwise use the itype of the aggregate.
5338 Set_Ekind
(Tmp
, E_Variable
);
5340 if not Is_Constrained
(Typ
) then
5341 Build_Constrained_Type
(Positional
=> False);
5343 elsif Is_Entity_Name
(Object_Definition
(Parent
(N
)))
5344 and then Is_Constrained
(Entity
(Object_Definition
(Parent
(N
))))
5346 Set_Etype
(Tmp
, Entity
(Object_Definition
(Parent
(N
))));
5349 Set_Size_Known_At_Compile_Time
(Typ
, False);
5350 Set_Etype
(Tmp
, Typ
);
5353 elsif Maybe_In_Place_OK
5354 and then Nkind
(Parent
(N
)) = N_Qualified_Expression
5355 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
5357 Set_Expansion_Delayed
(N
);
5360 -- In the remaining cases the aggregate is the RHS of an assignment
5362 elsif Maybe_In_Place_OK
5363 and then Safe_Left_Hand_Side
(Name
(Parent
(N
)))
5365 Tmp
:= Name
(Parent
(N
));
5367 if Etype
(Tmp
) /= Etype
(N
) then
5368 Apply_Length_Check
(N
, Etype
(Tmp
));
5370 if Nkind
(N
) = N_Raise_Constraint_Error
then
5372 -- Static error, nothing further to expand
5378 -- If a slice assignment has an aggregate with a single others_choice,
5379 -- the assignment can be done in place even if bounds are not static,
5380 -- by converting it into a loop over the discrete range of the slice.
5382 elsif Maybe_In_Place_OK
5383 and then Nkind
(Name
(Parent
(N
))) = N_Slice
5384 and then Is_Others_Aggregate
(N
)
5386 Tmp
:= Name
(Parent
(N
));
5388 -- Set type of aggregate to be type of lhs in assignment, in order
5389 -- to suppress redundant length checks.
5391 Set_Etype
(N
, Etype
(Tmp
));
5395 -- In place aggregate expansion is not possible
5398 Maybe_In_Place_OK
:= False;
5399 Tmp
:= Make_Temporary
(Loc
, 'A', N
);
5401 Make_Object_Declaration
(Loc
,
5402 Defining_Identifier
=> Tmp
,
5403 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
5404 Set_No_Initialization
(Tmp_Decl
, True);
5406 -- If we are within a loop, the temporary will be pushed on the
5407 -- stack at each iteration. If the aggregate is the expression for an
5408 -- allocator, it will be immediately copied to the heap and can
5409 -- be reclaimed at once. We create a transient scope around the
5410 -- aggregate for this purpose.
5412 if Ekind
(Current_Scope
) = E_Loop
5413 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
5415 Establish_Transient_Scope
(N
, False);
5418 Insert_Action
(N
, Tmp_Decl
);
5421 -- Construct and insert the aggregate code. We can safely suppress index
5422 -- checks because this code is guaranteed not to raise CE on index
5423 -- checks. However we should *not* suppress all checks.
5429 if Nkind
(Tmp
) = N_Defining_Identifier
then
5430 Target
:= New_Occurrence_Of
(Tmp
, Loc
);
5433 if Has_Default_Init_Comps
(N
) then
5435 -- Ada 2005 (AI-287): This case has not been analyzed???
5437 raise Program_Error
;
5440 -- Name in assignment is explicit dereference
5442 Target
:= New_Copy
(Tmp
);
5445 -- If we are to generate an in place assignment for a declaration or
5446 -- an assignment statement, and the assignment can be done directly
5447 -- by the back end, then do not expand further.
5449 -- ??? We can also do that if in place expansion is not possible but
5450 -- then we could go into an infinite recursion.
5452 if (In_Place_Assign_OK_For_Declaration
or else Maybe_In_Place_OK
)
5453 and then VM_Target
= No_VM
5454 and then not AAMP_On_Target
5455 and then not Generate_SCIL
5456 and then not Possible_Bit_Aligned_Component
(Target
)
5457 and then not Is_Possibly_Unaligned_Slice
(Target
)
5458 and then Aggr_Assignment_OK_For_Backend
(N
)
5460 if Maybe_In_Place_OK
then
5466 Make_Assignment_Statement
(Loc
,
5468 Expression
=> New_Copy
(N
)));
5472 Build_Array_Aggr_Code
(N
,
5474 Index
=> First_Index
(Typ
),
5476 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
5479 -- Save the last assignment statement associated with the aggregate
5480 -- when building a controlled object. This reference is utilized by
5481 -- the finalization machinery when marking an object as successfully
5484 if Needs_Finalization
(Typ
)
5485 and then Is_Entity_Name
(Target
)
5486 and then Present
(Entity
(Target
))
5487 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
5489 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
5493 -- If the aggregate is the expression in a declaration, the expanded
5494 -- code must be inserted after it. The defining entity might not come
5495 -- from source if this is part of an inlined body, but the declaration
5498 if Comes_From_Source
(Tmp
)
5500 (Nkind
(Parent
(N
)) = N_Object_Declaration
5501 and then Comes_From_Source
(Parent
(N
))
5502 and then Tmp
= Defining_Entity
(Parent
(N
)))
5505 Node_After
: constant Node_Id
:= Next
(Parent_Node
);
5508 Insert_Actions_After
(Parent_Node
, Aggr_Code
);
5510 if Parent_Kind
= N_Object_Declaration
then
5511 Collect_Initialization_Statements
5512 (Obj
=> Tmp
, N
=> Parent_Node
, Node_After
=> Node_After
);
5517 Insert_Actions
(N
, Aggr_Code
);
5520 -- If the aggregate has been assigned in place, remove the original
5523 if Nkind
(Parent
(N
)) = N_Assignment_Statement
5524 and then Maybe_In_Place_OK
5526 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
5528 elsif Nkind
(Parent
(N
)) /= N_Object_Declaration
5529 or else Tmp
/= Defining_Identifier
(Parent
(N
))
5531 Rewrite
(N
, New_Occurrence_Of
(Tmp
, Loc
));
5532 Analyze_And_Resolve
(N
, Typ
);
5534 end Expand_Array_Aggregate
;
5536 ------------------------
5537 -- Expand_N_Aggregate --
5538 ------------------------
5540 procedure Expand_N_Aggregate
(N
: Node_Id
) is
5542 -- Record aggregate case
5544 if Is_Record_Type
(Etype
(N
)) then
5545 Expand_Record_Aggregate
(N
);
5547 -- Array aggregate case
5550 -- A special case, if we have a string subtype with bounds 1 .. N,
5551 -- where N is known at compile time, and the aggregate is of the
5552 -- form (others => 'x'), with a single choice and no expressions,
5553 -- and N is less than 80 (an arbitrary limit for now), then replace
5554 -- the aggregate by the equivalent string literal (but do not mark
5555 -- it as static since it is not).
5557 -- Note: this entire circuit is redundant with respect to code in
5558 -- Expand_Array_Aggregate that collapses others choices to positional
5559 -- form, but there are two problems with that circuit:
5561 -- a) It is limited to very small cases due to ill-understood
5562 -- interactions with bootstrapping. That limit is removed by
5563 -- use of the No_Implicit_Loops restriction.
5565 -- b) It incorrectly ends up with the resulting expressions being
5566 -- considered static when they are not. For example, the
5567 -- following test should fail:
5569 -- pragma Restrictions (No_Implicit_Loops);
5570 -- package NonSOthers4 is
5571 -- B : constant String (1 .. 6) := (others => 'A');
5572 -- DH : constant String (1 .. 8) := B & "BB";
5574 -- pragma Export (C, X, Link_Name => DH);
5577 -- But it succeeds (DH looks static to pragma Export)
5579 -- To be sorted out ???
5581 if Present
(Component_Associations
(N
)) then
5583 CA
: constant Node_Id
:= First
(Component_Associations
(N
));
5584 MX
: constant := 80;
5587 if Nkind
(First
(Choices
(CA
))) = N_Others_Choice
5588 and then Nkind
(Expression
(CA
)) = N_Character_Literal
5589 and then No
(Expressions
(N
))
5592 T
: constant Entity_Id
:= Etype
(N
);
5593 X
: constant Node_Id
:= First_Index
(T
);
5594 EC
: constant Node_Id
:= Expression
(CA
);
5595 CV
: constant Uint
:= Char_Literal_Value
(EC
);
5596 CC
: constant Int
:= UI_To_Int
(CV
);
5599 if Nkind
(X
) = N_Range
5600 and then Compile_Time_Known_Value
(Low_Bound
(X
))
5601 and then Expr_Value
(Low_Bound
(X
)) = 1
5602 and then Compile_Time_Known_Value
(High_Bound
(X
))
5605 Hi
: constant Uint
:= Expr_Value
(High_Bound
(X
));
5611 for J
in 1 .. UI_To_Int
(Hi
) loop
5612 Store_String_Char
(Char_Code
(CC
));
5616 Make_String_Literal
(Sloc
(N
),
5617 Strval
=> End_String
));
5619 if CC
>= Int
(2 ** 16) then
5620 Set_Has_Wide_Wide_Character
(N
);
5621 elsif CC
>= Int
(2 ** 8) then
5622 Set_Has_Wide_Character
(N
);
5625 Analyze_And_Resolve
(N
, T
);
5626 Set_Is_Static_Expression
(N
, False);
5636 -- Not that special case, so normal expansion of array aggregate
5638 Expand_Array_Aggregate
(N
);
5642 when RE_Not_Available
=>
5644 end Expand_N_Aggregate
;
5646 ----------------------------------
5647 -- Expand_N_Extension_Aggregate --
5648 ----------------------------------
5650 -- If the ancestor part is an expression, add a component association for
5651 -- the parent field. If the type of the ancestor part is not the direct
5652 -- parent of the expected type, build recursively the needed ancestors.
5653 -- If the ancestor part is a subtype_mark, replace aggregate with a decla-
5654 -- ration for a temporary of the expected type, followed by individual
5655 -- assignments to the given components.
5657 procedure Expand_N_Extension_Aggregate
(N
: Node_Id
) is
5658 Loc
: constant Source_Ptr
:= Sloc
(N
);
5659 A
: constant Node_Id
:= Ancestor_Part
(N
);
5660 Typ
: constant Entity_Id
:= Etype
(N
);
5663 -- If the ancestor is a subtype mark, an init proc must be called
5664 -- on the resulting object which thus has to be materialized in
5667 if Is_Entity_Name
(A
) and then Is_Type
(Entity
(A
)) then
5668 Convert_To_Assignments
(N
, Typ
);
5670 -- The extension aggregate is transformed into a record aggregate
5671 -- of the following form (c1 and c2 are inherited components)
5673 -- (Exp with c3 => a, c4 => b)
5674 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c3 => a, c4 => b)
5679 if Tagged_Type_Expansion
then
5680 Expand_Record_Aggregate
(N
,
5683 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
),
5686 -- No tag is needed in the case of a VM
5689 Expand_Record_Aggregate
(N
, Parent_Expr
=> A
);
5694 when RE_Not_Available
=>
5696 end Expand_N_Extension_Aggregate
;
5698 -----------------------------
5699 -- Expand_Record_Aggregate --
5700 -----------------------------
5702 procedure Expand_Record_Aggregate
5704 Orig_Tag
: Node_Id
:= Empty
;
5705 Parent_Expr
: Node_Id
:= Empty
)
5707 Loc
: constant Source_Ptr
:= Sloc
(N
);
5708 Comps
: constant List_Id
:= Component_Associations
(N
);
5709 Typ
: constant Entity_Id
:= Etype
(N
);
5710 Base_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
5712 Static_Components
: Boolean := True;
5713 -- Flag to indicate whether all components are compile-time known,
5714 -- and the aggregate can be constructed statically and handled by
5717 function Compile_Time_Known_Composite_Value
(N
: Node_Id
) return Boolean;
5718 -- Returns true if N is an expression of composite type which can be
5719 -- fully evaluated at compile time without raising constraint error.
5720 -- Such expressions can be passed as is to Gigi without any expansion.
5722 -- This returns true for N_Aggregate with Compile_Time_Known_Aggregate
5723 -- set and constants whose expression is such an aggregate, recursively.
5725 function Component_Not_OK_For_Backend
return Boolean;
5726 -- Check for presence of a component which makes it impossible for the
5727 -- backend to process the aggregate, thus requiring the use of a series
5728 -- of assignment statements. Cases checked for are a nested aggregate
5729 -- needing Late_Expansion, the presence of a tagged component which may
5730 -- need tag adjustment, and a bit unaligned component reference.
5732 -- We also force expansion into assignments if a component is of a
5733 -- mutable type (including a private type with discriminants) because
5734 -- in that case the size of the component to be copied may be smaller
5735 -- than the side of the target, and there is no simple way for gigi
5736 -- to compute the size of the object to be copied.
5738 -- NOTE: This is part of the ongoing work to define precisely the
5739 -- interface between front-end and back-end handling of aggregates.
5740 -- In general it is desirable to pass aggregates as they are to gigi,
5741 -- in order to minimize elaboration code. This is one case where the
5742 -- semantics of Ada complicate the analysis and lead to anomalies in
5743 -- the gcc back-end if the aggregate is not expanded into assignments.
5745 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean;
5746 -- If any ancestor of the current type is private, the aggregate
5747 -- cannot be built in place. We cannot rely on Has_Private_Ancestor,
5748 -- because it will not be set when type and its parent are in the
5749 -- same scope, and the parent component needs expansion.
5751 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
;
5752 -- For nested aggregates return the ultimate enclosing aggregate; for
5753 -- non-nested aggregates return N.
5755 ----------------------------------------
5756 -- Compile_Time_Known_Composite_Value --
5757 ----------------------------------------
5759 function Compile_Time_Known_Composite_Value
5760 (N
: Node_Id
) return Boolean
5763 -- If we have an entity name, then see if it is the name of a
5764 -- constant and if so, test the corresponding constant value.
5766 if Is_Entity_Name
(N
) then
5768 E
: constant Entity_Id
:= Entity
(N
);
5771 if Ekind
(E
) /= E_Constant
then
5774 V
:= Constant_Value
(E
);
5776 and then Compile_Time_Known_Composite_Value
(V
);
5780 -- We have a value, see if it is compile time known
5783 if Nkind
(N
) = N_Aggregate
then
5784 return Compile_Time_Known_Aggregate
(N
);
5787 -- All other types of values are not known at compile time
5792 end Compile_Time_Known_Composite_Value
;
5794 ----------------------------------
5795 -- Component_Not_OK_For_Backend --
5796 ----------------------------------
5798 function Component_Not_OK_For_Backend
return Boolean is
5808 while Present
(C
) loop
5810 -- If the component has box initialization, expansion is needed
5811 -- and component is not ready for backend.
5813 if Box_Present
(C
) then
5817 if Nkind
(Expression
(C
)) = N_Qualified_Expression
then
5818 Expr_Q
:= Expression
(Expression
(C
));
5820 Expr_Q
:= Expression
(C
);
5823 -- Return true if the aggregate has any associations for tagged
5824 -- components that may require tag adjustment.
5826 -- These are cases where the source expression may have a tag that
5827 -- could differ from the component tag (e.g., can occur for type
5828 -- conversions and formal parameters). (Tag adjustment not needed
5829 -- if VM_Target because object tags are implicit in the machine.)
5831 if Is_Tagged_Type
(Etype
(Expr_Q
))
5832 and then (Nkind
(Expr_Q
) = N_Type_Conversion
5833 or else (Is_Entity_Name
(Expr_Q
)
5835 Ekind
(Entity
(Expr_Q
)) in Formal_Kind
))
5836 and then Tagged_Type_Expansion
5838 Static_Components
:= False;
5841 elsif Is_Delayed_Aggregate
(Expr_Q
) then
5842 Static_Components
:= False;
5845 elsif Possible_Bit_Aligned_Component
(Expr_Q
) then
5846 Static_Components
:= False;
5850 if Is_Elementary_Type
(Etype
(Expr_Q
)) then
5851 if not Compile_Time_Known_Value
(Expr_Q
) then
5852 Static_Components
:= False;
5855 elsif not Compile_Time_Known_Composite_Value
(Expr_Q
) then
5856 Static_Components
:= False;
5858 if Is_Private_Type
(Etype
(Expr_Q
))
5859 and then Has_Discriminants
(Etype
(Expr_Q
))
5869 end Component_Not_OK_For_Backend
;
5871 -----------------------------------
5872 -- Has_Visible_Private_Ancestor --
5873 -----------------------------------
5875 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean is
5876 R
: constant Entity_Id
:= Root_Type
(Id
);
5877 T1
: Entity_Id
:= Id
;
5881 if Is_Private_Type
(T1
) then
5891 end Has_Visible_Private_Ancestor
;
5893 -------------------------
5894 -- Top_Level_Aggregate --
5895 -------------------------
5897 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
is
5902 while Present
(Parent
(Aggr
))
5903 and then Nkind_In
(Parent
(Aggr
), N_Component_Association
,
5906 Aggr
:= Parent
(Aggr
);
5910 end Top_Level_Aggregate
;
5914 Top_Level_Aggr
: constant Node_Id
:= Top_Level_Aggregate
(N
);
5915 Tag_Value
: Node_Id
;
5919 -- Start of processing for Expand_Record_Aggregate
5922 -- If the aggregate is to be assigned to an atomic variable, we have
5923 -- to prevent a piecemeal assignment even if the aggregate is to be
5924 -- expanded. We create a temporary for the aggregate, and assign the
5925 -- temporary instead, so that the back end can generate an atomic move
5929 and then Comes_From_Source
(Parent
(N
))
5930 and then Is_Atomic_Aggregate
(N
, Typ
)
5934 -- No special management required for aggregates used to initialize
5935 -- statically allocated dispatch tables
5937 elsif Is_Static_Dispatch_Table_Aggregate
(N
) then
5941 -- Ada 2005 (AI-318-2): We need to convert to assignments if components
5942 -- are build-in-place function calls. The assignments will each turn
5943 -- into a build-in-place function call. If components are all static,
5944 -- we can pass the aggregate to the backend regardless of limitedness.
5946 -- Extension aggregates, aggregates in extended return statements, and
5947 -- aggregates for C++ imported types must be expanded.
5949 if Ada_Version
>= Ada_2005
and then Is_Limited_View
(Typ
) then
5950 if not Nkind_In
(Parent
(N
), N_Object_Declaration
,
5951 N_Component_Association
)
5953 Convert_To_Assignments
(N
, Typ
);
5955 elsif Nkind
(N
) = N_Extension_Aggregate
5956 or else Convention
(Typ
) = Convention_CPP
5958 Convert_To_Assignments
(N
, Typ
);
5960 elsif not Size_Known_At_Compile_Time
(Typ
)
5961 or else Component_Not_OK_For_Backend
5962 or else not Static_Components
5964 Convert_To_Assignments
(N
, Typ
);
5967 Set_Compile_Time_Known_Aggregate
(N
);
5968 Set_Expansion_Delayed
(N
, False);
5971 -- Gigi doesn't properly handle temporaries of variable size so we
5972 -- generate it in the front-end
5974 elsif not Size_Known_At_Compile_Time
(Typ
)
5975 and then Tagged_Type_Expansion
5977 Convert_To_Assignments
(N
, Typ
);
5979 -- An aggregate used to initialize a controlled object must be turned
5980 -- into component assignments as the components themselves may require
5981 -- finalization actions such as adjustment.
5983 elsif Needs_Finalization
(Typ
) then
5984 Convert_To_Assignments
(N
, Typ
);
5986 -- Ada 2005 (AI-287): In case of default initialized components we
5987 -- convert the aggregate into assignments.
5989 elsif Has_Default_Init_Comps
(N
) then
5990 Convert_To_Assignments
(N
, Typ
);
5994 elsif Component_Not_OK_For_Backend
then
5995 Convert_To_Assignments
(N
, Typ
);
5997 -- If an ancestor is private, some components are not inherited and we
5998 -- cannot expand into a record aggregate.
6000 elsif Has_Visible_Private_Ancestor
(Typ
) then
6001 Convert_To_Assignments
(N
, Typ
);
6003 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
6004 -- is not able to handle the aggregate for Late_Request.
6006 elsif Is_Tagged_Type
(Typ
) and then Has_Discriminants
(Typ
) then
6007 Convert_To_Assignments
(N
, Typ
);
6009 -- If the tagged types covers interface types we need to initialize all
6010 -- hidden components containing pointers to secondary dispatch tables.
6012 elsif Is_Tagged_Type
(Typ
) and then Has_Interfaces
(Typ
) then
6013 Convert_To_Assignments
(N
, Typ
);
6015 -- If some components are mutable, the size of the aggregate component
6016 -- may be distinct from the default size of the type component, so
6017 -- we need to expand to insure that the back-end copies the proper
6018 -- size of the data. However, if the aggregate is the initial value of
6019 -- a constant, the target is immutable and might be built statically
6020 -- if components are appropriate.
6022 elsif Has_Mutable_Components
(Typ
)
6024 (Nkind
(Parent
(Top_Level_Aggr
)) /= N_Object_Declaration
6025 or else not Constant_Present
(Parent
(Top_Level_Aggr
))
6026 or else not Static_Components
)
6028 Convert_To_Assignments
(N
, Typ
);
6030 -- If the type involved has bit aligned components, then we are not sure
6031 -- that the back end can handle this case correctly.
6033 elsif Type_May_Have_Bit_Aligned_Components
(Typ
) then
6034 Convert_To_Assignments
(N
, Typ
);
6036 -- In all other cases, build a proper aggregate to be handled by gigi
6039 if Nkind
(N
) = N_Aggregate
then
6041 -- If the aggregate is static and can be handled by the back-end,
6042 -- nothing left to do.
6044 if Static_Components
then
6045 Set_Compile_Time_Known_Aggregate
(N
);
6046 Set_Expansion_Delayed
(N
, False);
6050 -- If no discriminants, nothing special to do
6052 if not Has_Discriminants
(Typ
) then
6055 -- Case of discriminants present
6057 elsif Is_Derived_Type
(Typ
) then
6059 -- For untagged types, non-stored discriminants are replaced
6060 -- with stored discriminants, which are the ones that gigi uses
6061 -- to describe the type and its components.
6063 Generate_Aggregate_For_Derived_Type
: declare
6064 Constraints
: constant List_Id
:= New_List
;
6065 First_Comp
: Node_Id
;
6066 Discriminant
: Entity_Id
;
6068 Num_Disc
: Int
:= 0;
6069 Num_Gird
: Int
:= 0;
6071 procedure Prepend_Stored_Values
(T
: Entity_Id
);
6072 -- Scan the list of stored discriminants of the type, and add
6073 -- their values to the aggregate being built.
6075 ---------------------------
6076 -- Prepend_Stored_Values --
6077 ---------------------------
6079 procedure Prepend_Stored_Values
(T
: Entity_Id
) is
6081 Discriminant
:= First_Stored_Discriminant
(T
);
6082 while Present
(Discriminant
) loop
6084 Make_Component_Association
(Loc
,
6086 New_List
(New_Occurrence_Of
(Discriminant
, Loc
)),
6090 (Get_Discriminant_Value
6093 Discriminant_Constraint
(Typ
))));
6095 if No
(First_Comp
) then
6096 Prepend_To
(Component_Associations
(N
), New_Comp
);
6098 Insert_After
(First_Comp
, New_Comp
);
6101 First_Comp
:= New_Comp
;
6102 Next_Stored_Discriminant
(Discriminant
);
6104 end Prepend_Stored_Values
;
6106 -- Start of processing for Generate_Aggregate_For_Derived_Type
6109 -- Remove the associations for the discriminant of derived type
6111 First_Comp
:= First
(Component_Associations
(N
));
6112 while Present
(First_Comp
) loop
6116 if Ekind
(Entity
(First
(Choices
(Comp
)))) = E_Discriminant
6119 Num_Disc
:= Num_Disc
+ 1;
6123 -- Insert stored discriminant associations in the correct
6124 -- order. If there are more stored discriminants than new
6125 -- discriminants, there is at least one new discriminant that
6126 -- constrains more than one of the stored discriminants. In
6127 -- this case we need to construct a proper subtype of the
6128 -- parent type, in order to supply values to all the
6129 -- components. Otherwise there is one-one correspondence
6130 -- between the constraints and the stored discriminants.
6132 First_Comp
:= Empty
;
6134 Discriminant
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6135 while Present
(Discriminant
) loop
6136 Num_Gird
:= Num_Gird
+ 1;
6137 Next_Stored_Discriminant
(Discriminant
);
6140 -- Case of more stored discriminants than new discriminants
6142 if Num_Gird
> Num_Disc
then
6144 -- Create a proper subtype of the parent type, which is the
6145 -- proper implementation type for the aggregate, and convert
6146 -- it to the intended target type.
6148 Discriminant
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6149 while Present
(Discriminant
) loop
6152 (Get_Discriminant_Value
6155 Discriminant_Constraint
(Typ
)));
6156 Append
(New_Comp
, Constraints
);
6157 Next_Stored_Discriminant
(Discriminant
);
6161 Make_Subtype_Declaration
(Loc
,
6162 Defining_Identifier
=> Make_Temporary
(Loc
, 'T'),
6163 Subtype_Indication
=>
6164 Make_Subtype_Indication
(Loc
,
6166 New_Occurrence_Of
(Etype
(Base_Type
(Typ
)), Loc
),
6168 Make_Index_Or_Discriminant_Constraint
6169 (Loc
, Constraints
)));
6171 Insert_Action
(N
, Decl
);
6172 Prepend_Stored_Values
(Base_Type
(Typ
));
6174 Set_Etype
(N
, Defining_Identifier
(Decl
));
6177 Rewrite
(N
, Unchecked_Convert_To
(Typ
, N
));
6180 -- Case where we do not have fewer new discriminants than
6181 -- stored discriminants, so in this case we can simply use the
6182 -- stored discriminants of the subtype.
6185 Prepend_Stored_Values
(Typ
);
6187 end Generate_Aggregate_For_Derived_Type
;
6190 if Is_Tagged_Type
(Typ
) then
6192 -- In the tagged case, _parent and _tag component must be created
6194 -- Reset Null_Present unconditionally. Tagged records always have
6195 -- at least one field (the tag or the parent).
6197 Set_Null_Record_Present
(N
, False);
6199 -- When the current aggregate comes from the expansion of an
6200 -- extension aggregate, the parent expr is replaced by an
6201 -- aggregate formed by selected components of this expr.
6203 if Present
(Parent_Expr
) and then Is_Empty_List
(Comps
) then
6204 Comp
:= First_Component_Or_Discriminant
(Typ
);
6205 while Present
(Comp
) loop
6207 -- Skip all expander-generated components
6209 if not Comes_From_Source
(Original_Record_Component
(Comp
))
6215 Make_Selected_Component
(Loc
,
6217 Unchecked_Convert_To
(Typ
,
6218 Duplicate_Subexpr
(Parent_Expr
, True)),
6219 Selector_Name
=> New_Occurrence_Of
(Comp
, Loc
));
6222 Make_Component_Association
(Loc
,
6224 New_List
(New_Occurrence_Of
(Comp
, Loc
)),
6225 Expression
=> New_Comp
));
6227 Analyze_And_Resolve
(New_Comp
, Etype
(Comp
));
6230 Next_Component_Or_Discriminant
(Comp
);
6234 -- Compute the value for the Tag now, if the type is a root it
6235 -- will be included in the aggregate right away, otherwise it will
6236 -- be propagated to the parent aggregate.
6238 if Present
(Orig_Tag
) then
6239 Tag_Value
:= Orig_Tag
;
6240 elsif not Tagged_Type_Expansion
then
6245 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
);
6248 -- For a derived type, an aggregate for the parent is formed with
6249 -- all the inherited components.
6251 if Is_Derived_Type
(Typ
) then
6254 First_Comp
: Node_Id
;
6255 Parent_Comps
: List_Id
;
6256 Parent_Aggr
: Node_Id
;
6257 Parent_Name
: Node_Id
;
6260 -- Remove the inherited component association from the
6261 -- aggregate and store them in the parent aggregate
6263 First_Comp
:= First
(Component_Associations
(N
));
6264 Parent_Comps
:= New_List
;
6265 while Present
(First_Comp
)
6267 Scope
(Original_Record_Component
6268 (Entity
(First
(Choices
(First_Comp
))))) /=
6274 Append
(Comp
, Parent_Comps
);
6278 Make_Aggregate
(Loc
,
6279 Component_Associations
=> Parent_Comps
);
6280 Set_Etype
(Parent_Aggr
, Etype
(Base_Type
(Typ
)));
6282 -- Find the _parent component
6284 Comp
:= First_Component
(Typ
);
6285 while Chars
(Comp
) /= Name_uParent
loop
6286 Comp
:= Next_Component
(Comp
);
6289 Parent_Name
:= New_Occurrence_Of
(Comp
, Loc
);
6291 -- Insert the parent aggregate
6293 Prepend_To
(Component_Associations
(N
),
6294 Make_Component_Association
(Loc
,
6295 Choices
=> New_List
(Parent_Name
),
6296 Expression
=> Parent_Aggr
));
6298 -- Expand recursively the parent propagating the right Tag
6300 Expand_Record_Aggregate
6301 (Parent_Aggr
, Tag_Value
, Parent_Expr
);
6303 -- The ancestor part may be a nested aggregate that has
6304 -- delayed expansion: recheck now.
6306 if Component_Not_OK_For_Backend
then
6307 Convert_To_Assignments
(N
, Typ
);
6311 -- For a root type, the tag component is added (unless compiling
6312 -- for the VMs, where tags are implicit).
6314 elsif Tagged_Type_Expansion
then
6316 Tag_Name
: constant Node_Id
:=
6317 New_Occurrence_Of
(First_Tag_Component
(Typ
), Loc
);
6318 Typ_Tag
: constant Entity_Id
:= RTE
(RE_Tag
);
6319 Conv_Node
: constant Node_Id
:=
6320 Unchecked_Convert_To
(Typ_Tag
, Tag_Value
);
6323 Set_Etype
(Conv_Node
, Typ_Tag
);
6324 Prepend_To
(Component_Associations
(N
),
6325 Make_Component_Association
(Loc
,
6326 Choices
=> New_List
(Tag_Name
),
6327 Expression
=> Conv_Node
));
6333 end Expand_Record_Aggregate
;
6335 ----------------------------
6336 -- Has_Default_Init_Comps --
6337 ----------------------------
6339 function Has_Default_Init_Comps
(N
: Node_Id
) return Boolean is
6340 Comps
: constant List_Id
:= Component_Associations
(N
);
6345 pragma Assert
(Nkind_In
(N
, N_Aggregate
, N_Extension_Aggregate
));
6351 if Has_Self_Reference
(N
) then
6355 -- Check if any direct component has default initialized components
6358 while Present
(C
) loop
6359 if Box_Present
(C
) then
6366 -- Recursive call in case of aggregate expression
6369 while Present
(C
) loop
6370 Expr
:= Expression
(C
);
6373 and then Nkind_In
(Expr
, N_Aggregate
, N_Extension_Aggregate
)
6374 and then Has_Default_Init_Comps
(Expr
)
6383 end Has_Default_Init_Comps
;
6385 --------------------------
6386 -- Is_Delayed_Aggregate --
6387 --------------------------
6389 function Is_Delayed_Aggregate
(N
: Node_Id
) return Boolean is
6390 Node
: Node_Id
:= N
;
6391 Kind
: Node_Kind
:= Nkind
(Node
);
6394 if Kind
= N_Qualified_Expression
then
6395 Node
:= Expression
(Node
);
6396 Kind
:= Nkind
(Node
);
6399 if not Nkind_In
(Kind
, N_Aggregate
, N_Extension_Aggregate
) then
6402 return Expansion_Delayed
(Node
);
6404 end Is_Delayed_Aggregate
;
6406 ----------------------------------------
6407 -- Is_Static_Dispatch_Table_Aggregate --
6408 ----------------------------------------
6410 function Is_Static_Dispatch_Table_Aggregate
(N
: Node_Id
) return Boolean is
6411 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
6414 return Static_Dispatch_Tables
6415 and then Tagged_Type_Expansion
6416 and then RTU_Loaded
(Ada_Tags
)
6418 -- Avoid circularity when rebuilding the compiler
6420 and then Cunit_Entity
(Get_Source_Unit
(N
)) /= RTU_Entity
(Ada_Tags
)
6421 and then (Typ
= RTE
(RE_Dispatch_Table_Wrapper
)
6423 Typ
= RTE
(RE_Address_Array
)
6425 Typ
= RTE
(RE_Type_Specific_Data
)
6427 Typ
= RTE
(RE_Tag_Table
)
6429 (RTE_Available
(RE_Interface_Data
)
6430 and then Typ
= RTE
(RE_Interface_Data
))
6432 (RTE_Available
(RE_Interfaces_Array
)
6433 and then Typ
= RTE
(RE_Interfaces_Array
))
6435 (RTE_Available
(RE_Interface_Data_Element
)
6436 and then Typ
= RTE
(RE_Interface_Data_Element
)));
6437 end Is_Static_Dispatch_Table_Aggregate
;
6439 -----------------------------
6440 -- Is_Two_Dim_Packed_Array --
6441 -----------------------------
6443 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean is
6444 C
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
6446 return Number_Dimensions
(Typ
) = 2
6447 and then Is_Bit_Packed_Array
(Typ
)
6448 and then (C
= 1 or else C
= 2 or else C
= 4);
6449 end Is_Two_Dim_Packed_Array
;
6451 --------------------
6452 -- Late_Expansion --
6453 --------------------
6455 function Late_Expansion
6458 Target
: Node_Id
) return List_Id
6460 Aggr_Code
: List_Id
;
6463 if Is_Record_Type
(Etype
(N
)) then
6464 Aggr_Code
:= Build_Record_Aggr_Code
(N
, Typ
, Target
);
6466 else pragma Assert
(Is_Array_Type
(Etype
(N
)));
6468 Build_Array_Aggr_Code
6470 Ctype
=> Component_Type
(Etype
(N
)),
6471 Index
=> First_Index
(Typ
),
6473 Scalar_Comp
=> Is_Scalar_Type
(Component_Type
(Typ
)),
6474 Indexes
=> No_List
);
6477 -- Save the last assignment statement associated with the aggregate
6478 -- when building a controlled object. This reference is utilized by
6479 -- the finalization machinery when marking an object as successfully
6482 if Needs_Finalization
(Typ
)
6483 and then Is_Entity_Name
(Target
)
6484 and then Present
(Entity
(Target
))
6485 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
6487 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
6493 ----------------------------------
6494 -- Make_OK_Assignment_Statement --
6495 ----------------------------------
6497 function Make_OK_Assignment_Statement
6500 Expression
: Node_Id
) return Node_Id
6503 Set_Assignment_OK
(Name
);
6504 return Make_Assignment_Statement
(Sloc
, Name
, Expression
);
6505 end Make_OK_Assignment_Statement
;
6507 -----------------------
6508 -- Number_Of_Choices --
6509 -----------------------
6511 function Number_Of_Choices
(N
: Node_Id
) return Nat
is
6515 Nb_Choices
: Nat
:= 0;
6518 if Present
(Expressions
(N
)) then
6522 Assoc
:= First
(Component_Associations
(N
));
6523 while Present
(Assoc
) loop
6524 Choice
:= First
(Choices
(Assoc
));
6525 while Present
(Choice
) loop
6526 if Nkind
(Choice
) /= N_Others_Choice
then
6527 Nb_Choices
:= Nb_Choices
+ 1;
6537 end Number_Of_Choices
;
6539 ------------------------------------
6540 -- Packed_Array_Aggregate_Handled --
6541 ------------------------------------
6543 -- The current version of this procedure will handle at compile time
6544 -- any array aggregate that meets these conditions:
6546 -- One and two dimensional, bit packed
6547 -- Underlying packed type is modular type
6548 -- Bounds are within 32-bit Int range
6549 -- All bounds and values are static
6551 -- Note: for now, in the 2-D case, we only handle component sizes of
6552 -- 1, 2, 4 (cases where an integral number of elements occupies a byte).
6554 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean is
6555 Loc
: constant Source_Ptr
:= Sloc
(N
);
6556 Typ
: constant Entity_Id
:= Etype
(N
);
6557 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
6559 Not_Handled
: exception;
6560 -- Exception raised if this aggregate cannot be handled
6563 -- Handle one- or two dimensional bit packed array
6565 if not Is_Bit_Packed_Array
(Typ
)
6566 or else Number_Dimensions
(Typ
) > 2
6571 -- If two-dimensional, check whether it can be folded, and transformed
6572 -- into a one-dimensional aggregate for the Packed_Array_Impl_Type of
6573 -- the original type.
6575 if Number_Dimensions
(Typ
) = 2 then
6576 return Two_Dim_Packed_Array_Handled
(N
);
6579 if not Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
)) then
6583 if not Is_Scalar_Type
(Component_Type
(Typ
))
6584 and then Has_Non_Standard_Rep
(Component_Type
(Typ
))
6590 Csiz
: constant Nat
:= UI_To_Int
(Component_Size
(Typ
));
6594 -- Bounds of index type
6598 -- Values of bounds if compile time known
6600 function Get_Component_Val
(N
: Node_Id
) return Uint
;
6601 -- Given a expression value N of the component type Ctyp, returns a
6602 -- value of Csiz (component size) bits representing this value. If
6603 -- the value is non-static or any other reason exists why the value
6604 -- cannot be returned, then Not_Handled is raised.
6606 -----------------------
6607 -- Get_Component_Val --
6608 -----------------------
6610 function Get_Component_Val
(N
: Node_Id
) return Uint
is
6614 -- We have to analyze the expression here before doing any further
6615 -- processing here. The analysis of such expressions is deferred
6616 -- till expansion to prevent some problems of premature analysis.
6618 Analyze_And_Resolve
(N
, Ctyp
);
6620 -- Must have a compile time value. String literals have to be
6621 -- converted into temporaries as well, because they cannot easily
6622 -- be converted into their bit representation.
6624 if not Compile_Time_Known_Value
(N
)
6625 or else Nkind
(N
) = N_String_Literal
6630 Val
:= Expr_Rep_Value
(N
);
6632 -- Adjust for bias, and strip proper number of bits
6634 if Has_Biased_Representation
(Ctyp
) then
6635 Val
:= Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
6638 return Val
mod Uint_2
** Csiz
;
6639 end Get_Component_Val
;
6641 -- Here we know we have a one dimensional bit packed array
6644 Get_Index_Bounds
(First_Index
(Typ
), Lo
, Hi
);
6646 -- Cannot do anything if bounds are dynamic
6648 if not Compile_Time_Known_Value
(Lo
)
6650 not Compile_Time_Known_Value
(Hi
)
6655 -- Or are silly out of range of int bounds
6657 Lob
:= Expr_Value
(Lo
);
6658 Hib
:= Expr_Value
(Hi
);
6660 if not UI_Is_In_Int_Range
(Lob
)
6662 not UI_Is_In_Int_Range
(Hib
)
6667 -- At this stage we have a suitable aggregate for handling at compile
6668 -- time. The only remaining checks are that the values of expressions
6669 -- in the aggregate are compile-time known (checks are performed by
6670 -- Get_Component_Val), and that any subtypes or ranges are statically
6673 -- If the aggregate is not fully positional at this stage, then
6674 -- convert it to positional form. Either this will fail, in which
6675 -- case we can do nothing, or it will succeed, in which case we have
6676 -- succeeded in handling the aggregate and transforming it into a
6677 -- modular value, or it will stay an aggregate, in which case we
6678 -- have failed to create a packed value for it.
6680 if Present
(Component_Associations
(N
)) then
6681 Convert_To_Positional
6682 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
6683 return Nkind
(N
) /= N_Aggregate
;
6686 -- Otherwise we are all positional, so convert to proper value
6689 Lov
: constant Int
:= UI_To_Int
(Lob
);
6690 Hiv
: constant Int
:= UI_To_Int
(Hib
);
6692 Len
: constant Nat
:= Int
'Max (0, Hiv
- Lov
+ 1);
6693 -- The length of the array (number of elements)
6695 Aggregate_Val
: Uint
;
6696 -- Value of aggregate. The value is set in the low order bits of
6697 -- this value. For the little-endian case, the values are stored
6698 -- from low-order to high-order and for the big-endian case the
6699 -- values are stored from high-order to low-order. Note that gigi
6700 -- will take care of the conversions to left justify the value in
6701 -- the big endian case (because of left justified modular type
6702 -- processing), so we do not have to worry about that here.
6705 -- Integer literal for resulting constructed value
6708 -- Shift count from low order for next value
6711 -- Shift increment for loop
6714 -- Next expression from positional parameters of aggregate
6716 Left_Justified
: Boolean;
6717 -- Set True if we are filling the high order bits of the target
6718 -- value (i.e. the value is left justified).
6721 -- For little endian, we fill up the low order bits of the target
6722 -- value. For big endian we fill up the high order bits of the
6723 -- target value (which is a left justified modular value).
6725 Left_Justified
:= Bytes_Big_Endian
;
6727 -- Switch justification if using -gnatd8
6729 if Debug_Flag_8
then
6730 Left_Justified
:= not Left_Justified
;
6733 -- Switch justfification if reverse storage order
6735 if Reverse_Storage_Order
(Base_Type
(Typ
)) then
6736 Left_Justified
:= not Left_Justified
;
6739 if Left_Justified
then
6740 Shift
:= Csiz
* (Len
- 1);
6747 -- Loop to set the values
6750 Aggregate_Val
:= Uint_0
;
6752 Expr
:= First
(Expressions
(N
));
6753 Aggregate_Val
:= Get_Component_Val
(Expr
) * Uint_2
** Shift
;
6755 for J
in 2 .. Len
loop
6756 Shift
:= Shift
+ Incr
;
6759 Aggregate_Val
+ Get_Component_Val
(Expr
) * Uint_2
** Shift
;
6763 -- Now we can rewrite with the proper value
6765 Lit
:= Make_Integer_Literal
(Loc
, Intval
=> Aggregate_Val
);
6766 Set_Print_In_Hex
(Lit
);
6768 -- Construct the expression using this literal. Note that it is
6769 -- important to qualify the literal with its proper modular type
6770 -- since universal integer does not have the required range and
6771 -- also this is a left justified modular type, which is important
6772 -- in the big-endian case.
6775 Unchecked_Convert_To
(Typ
,
6776 Make_Qualified_Expression
(Loc
,
6778 New_Occurrence_Of
(Packed_Array_Impl_Type
(Typ
), Loc
),
6779 Expression
=> Lit
)));
6781 Analyze_And_Resolve
(N
, Typ
);
6789 end Packed_Array_Aggregate_Handled
;
6791 ----------------------------
6792 -- Has_Mutable_Components --
6793 ----------------------------
6795 function Has_Mutable_Components
(Typ
: Entity_Id
) return Boolean is
6799 Comp
:= First_Component
(Typ
);
6800 while Present
(Comp
) loop
6801 if Is_Record_Type
(Etype
(Comp
))
6802 and then Has_Discriminants
(Etype
(Comp
))
6803 and then not Is_Constrained
(Etype
(Comp
))
6808 Next_Component
(Comp
);
6812 end Has_Mutable_Components
;
6814 ------------------------------
6815 -- Initialize_Discriminants --
6816 ------------------------------
6818 procedure Initialize_Discriminants
(N
: Node_Id
; Typ
: Entity_Id
) is
6819 Loc
: constant Source_Ptr
:= Sloc
(N
);
6820 Bas
: constant Entity_Id
:= Base_Type
(Typ
);
6821 Par
: constant Entity_Id
:= Etype
(Bas
);
6822 Decl
: constant Node_Id
:= Parent
(Par
);
6826 if Is_Tagged_Type
(Bas
)
6827 and then Is_Derived_Type
(Bas
)
6828 and then Has_Discriminants
(Par
)
6829 and then Has_Discriminants
(Bas
)
6830 and then Number_Discriminants
(Bas
) /= Number_Discriminants
(Par
)
6831 and then Nkind
(Decl
) = N_Full_Type_Declaration
6832 and then Nkind
(Type_Definition
(Decl
)) = N_Record_Definition
6834 Present
(Variant_Part
(Component_List
(Type_Definition
(Decl
))))
6835 and then Nkind
(N
) /= N_Extension_Aggregate
6838 -- Call init proc to set discriminants.
6839 -- There should eventually be a special procedure for this ???
6841 Ref
:= New_Occurrence_Of
(Defining_Identifier
(N
), Loc
);
6842 Insert_Actions_After
(N
,
6843 Build_Initialization_Call
(Sloc
(N
), Ref
, Typ
));
6845 end Initialize_Discriminants
;
6852 (Obj_Type
: Entity_Id
;
6853 Typ
: Entity_Id
) return Boolean
6855 L1
, L2
, H1
, H2
: Node_Id
;
6858 -- No sliding if the type of the object is not established yet, if it is
6859 -- an unconstrained type whose actual subtype comes from the aggregate,
6860 -- or if the two types are identical.
6862 if not Is_Array_Type
(Obj_Type
) then
6865 elsif not Is_Constrained
(Obj_Type
) then
6868 elsif Typ
= Obj_Type
then
6872 -- Sliding can only occur along the first dimension
6874 Get_Index_Bounds
(First_Index
(Typ
), L1
, H1
);
6875 Get_Index_Bounds
(First_Index
(Obj_Type
), L2
, H2
);
6877 if not Is_OK_Static_Expression
(L1
) or else
6878 not Is_OK_Static_Expression
(L2
) or else
6879 not Is_OK_Static_Expression
(H1
) or else
6880 not Is_OK_Static_Expression
(H2
)
6884 return Expr_Value
(L1
) /= Expr_Value
(L2
)
6886 Expr_Value
(H1
) /= Expr_Value
(H2
);
6891 ----------------------------------
6892 -- Two_Dim_Packed_Array_Handled --
6893 ----------------------------------
6895 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean is
6896 Loc
: constant Source_Ptr
:= Sloc
(N
);
6897 Typ
: constant Entity_Id
:= Etype
(N
);
6898 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
6899 Comp_Size
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
6900 Packed_Array
: constant Entity_Id
:=
6901 Packed_Array_Impl_Type
(Base_Type
(Typ
));
6904 -- Expression in original aggregate
6907 -- One-dimensional subaggregate
6911 -- For now, only deal with cases where an integral number of elements
6912 -- fit in a single byte. This includes the most common boolean case.
6914 if not (Comp_Size
= 1 or else
6915 Comp_Size
= 2 or else
6921 Convert_To_Positional
6922 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
6924 -- Verify that all components are static
6926 if Nkind
(N
) = N_Aggregate
6927 and then Compile_Time_Known_Aggregate
(N
)
6931 -- The aggregate may have been re-analyzed and converted already
6933 elsif Nkind
(N
) /= N_Aggregate
then
6936 -- If component associations remain, the aggregate is not static
6938 elsif Present
(Component_Associations
(N
)) then
6942 One_Dim
:= First
(Expressions
(N
));
6943 while Present
(One_Dim
) loop
6944 if Present
(Component_Associations
(One_Dim
)) then
6948 One_Comp
:= First
(Expressions
(One_Dim
));
6949 while Present
(One_Comp
) loop
6950 if not Is_OK_Static_Expression
(One_Comp
) then
6961 -- Two-dimensional aggregate is now fully positional so pack one
6962 -- dimension to create a static one-dimensional array, and rewrite
6963 -- as an unchecked conversion to the original type.
6966 Byte_Size
: constant Int
:= UI_To_Int
(Component_Size
(Packed_Array
));
6967 -- The packed array type is a byte array
6970 -- Number of components accumulated in current byte
6973 -- Assembled list of packed values for equivalent aggregate
6976 -- integer value of component
6979 -- Step size for packing
6982 -- Endian-dependent start position for packing
6985 -- Current insertion position
6988 -- Component of packed array being assembled.
6995 -- Account for endianness. See corresponding comment in
6996 -- Packed_Array_Aggregate_Handled concerning the following.
7000 xor Reverse_Storage_Order
(Base_Type
(Typ
))
7002 Init_Shift
:= Byte_Size
- Comp_Size
;
7009 -- Iterate over each subaggregate
7011 Shift
:= Init_Shift
;
7012 One_Dim
:= First
(Expressions
(N
));
7013 while Present
(One_Dim
) loop
7014 One_Comp
:= First
(Expressions
(One_Dim
));
7015 while Present
(One_Comp
) loop
7016 if Packed_Num
= Byte_Size
/ Comp_Size
then
7018 -- Byte is complete, add to list of expressions
7020 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
7022 Shift
:= Init_Shift
;
7026 Comp_Val
:= Expr_Rep_Value
(One_Comp
);
7028 -- Adjust for bias, and strip proper number of bits
7030 if Has_Biased_Representation
(Ctyp
) then
7031 Comp_Val
:= Comp_Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
7034 Comp_Val
:= Comp_Val
mod Uint_2
** Comp_Size
;
7035 Val
:= UI_To_Int
(Val
+ Comp_Val
* Uint_2
** Shift
);
7036 Shift
:= Shift
+ Incr
;
7037 One_Comp
:= Next
(One_Comp
);
7038 Packed_Num
:= Packed_Num
+ 1;
7042 One_Dim
:= Next
(One_Dim
);
7045 if Packed_Num
> 0 then
7047 -- Add final incomplete byte if present
7049 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
7053 Unchecked_Convert_To
(Typ
,
7054 Make_Qualified_Expression
(Loc
,
7055 Subtype_Mark
=> New_Occurrence_Of
(Packed_Array
, Loc
),
7056 Expression
=> Make_Aggregate
(Loc
, Expressions
=> Comps
))));
7057 Analyze_And_Resolve
(N
);
7060 end Two_Dim_Packed_Array_Handled
;
7062 ---------------------
7063 -- Sort_Case_Table --
7064 ---------------------
7066 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
) is
7067 L
: constant Int
:= Case_Table
'First;
7068 U
: constant Int
:= Case_Table
'Last;
7076 T
:= Case_Table
(K
+ 1);
7080 and then Expr_Value
(Case_Table
(J
- 1).Choice_Lo
) >
7081 Expr_Value
(T
.Choice_Lo
)
7083 Case_Table
(J
) := Case_Table
(J
- 1);
7087 Case_Table
(J
) := T
;
7090 end Sort_Case_Table
;
7092 ----------------------------
7093 -- Static_Array_Aggregate --
7094 ----------------------------
7096 function Static_Array_Aggregate
(N
: Node_Id
) return Boolean is
7097 Bounds
: constant Node_Id
:= Aggregate_Bounds
(N
);
7099 Typ
: constant Entity_Id
:= Etype
(N
);
7100 Comp_Type
: constant Entity_Id
:= Component_Type
(Typ
);
7107 if Is_Tagged_Type
(Typ
)
7108 or else Is_Controlled
(Typ
)
7109 or else Is_Packed
(Typ
)
7115 and then Nkind
(Bounds
) = N_Range
7116 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
7117 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
7119 Lo
:= Low_Bound
(Bounds
);
7120 Hi
:= High_Bound
(Bounds
);
7122 if No
(Component_Associations
(N
)) then
7124 -- Verify that all components are static integers
7126 Expr
:= First
(Expressions
(N
));
7127 while Present
(Expr
) loop
7128 if Nkind
(Expr
) /= N_Integer_Literal
then
7138 -- We allow only a single named association, either a static
7139 -- range or an others_clause, with a static expression.
7141 Expr
:= First
(Component_Associations
(N
));
7143 if Present
(Expressions
(N
)) then
7146 elsif Present
(Next
(Expr
)) then
7149 elsif Present
(Next
(First
(Choices
(Expr
)))) then
7153 -- The aggregate is static if all components are literals,
7154 -- or else all its components are static aggregates for the
7155 -- component type. We also limit the size of a static aggregate
7156 -- to prevent runaway static expressions.
7158 if Is_Array_Type
(Comp_Type
)
7159 or else Is_Record_Type
(Comp_Type
)
7161 if Nkind
(Expression
(Expr
)) /= N_Aggregate
7163 not Compile_Time_Known_Aggregate
(Expression
(Expr
))
7168 elsif Nkind
(Expression
(Expr
)) /= N_Integer_Literal
then
7172 if not Aggr_Size_OK
(N
, Typ
) then
7176 -- Create a positional aggregate with the right number of
7177 -- copies of the expression.
7179 Agg
:= Make_Aggregate
(Sloc
(N
), New_List
, No_List
);
7181 for I
in UI_To_Int
(Intval
(Lo
)) .. UI_To_Int
(Intval
(Hi
))
7183 Append_To
(Expressions
(Agg
), New_Copy
(Expression
(Expr
)));
7185 -- The copied expression must be analyzed and resolved.
7186 -- Besides setting the type, this ensures that static
7187 -- expressions are appropriately marked as such.
7190 (Last
(Expressions
(Agg
)), Component_Type
(Typ
));
7193 Set_Aggregate_Bounds
(Agg
, Bounds
);
7194 Set_Etype
(Agg
, Typ
);
7197 Set_Compile_Time_Known_Aggregate
(N
);
7206 end Static_Array_Aggregate
;