1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2018, 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 Freeze
; use Freeze
;
41 with Itypes
; use Itypes
;
43 with Namet
; use Namet
;
44 with Nmake
; use Nmake
;
45 with Nlists
; use Nlists
;
47 with Restrict
; use Restrict
;
48 with Rident
; use Rident
;
49 with Rtsfind
; use Rtsfind
;
50 with Ttypes
; use Ttypes
;
52 with Sem_Aggr
; use Sem_Aggr
;
53 with Sem_Aux
; use Sem_Aux
;
54 with Sem_Ch3
; use Sem_Ch3
;
55 with Sem_Eval
; use Sem_Eval
;
56 with Sem_Res
; use Sem_Res
;
57 with Sem_Util
; use Sem_Util
;
58 with Sinfo
; use Sinfo
;
59 with Snames
; use Snames
;
60 with Stand
; use Stand
;
61 with Stringt
; use Stringt
;
62 with Tbuild
; use Tbuild
;
63 with Uintp
; use Uintp
;
64 with Urealp
; use Urealp
;
66 package body Exp_Aggr
is
68 type Case_Bounds
is record
71 Choice_Node
: Node_Id
;
74 type Case_Table_Type
is array (Nat
range <>) of Case_Bounds
;
75 -- Table type used by Check_Case_Choices procedure
77 procedure Collect_Initialization_Statements
80 Node_After
: Node_Id
);
81 -- If Obj is not frozen, collect actions inserted after N until, but not
82 -- including, Node_After, for initialization of Obj, and move them to an
83 -- expression with actions, which becomes the Initialization_Statements for
86 procedure Expand_Delta_Array_Aggregate
(N
: Node_Id
; Deltas
: List_Id
);
87 procedure Expand_Delta_Record_Aggregate
(N
: Node_Id
; Deltas
: List_Id
);
89 function Has_Default_Init_Comps
(N
: Node_Id
) return Boolean;
90 -- N is an aggregate (record or array). Checks the presence of default
91 -- initialization (<>) in any component (Ada 2005: AI-287).
93 function In_Object_Declaration
(N
: Node_Id
) return Boolean;
94 -- Return True if N is part of an object declaration, False otherwise
96 function Is_Static_Dispatch_Table_Aggregate
(N
: Node_Id
) return Boolean;
97 -- Returns true if N is an aggregate used to initialize the components
98 -- of a statically allocated dispatch table.
100 function Late_Expansion
103 Target
: Node_Id
) return List_Id
;
104 -- This routine implements top-down expansion of nested aggregates. In
105 -- doing so, it avoids the generation of temporaries at each level. N is
106 -- a nested record or array aggregate with the Expansion_Delayed flag.
107 -- Typ is the expected type of the aggregate. Target is a (duplicatable)
108 -- expression that will hold the result of the aggregate expansion.
110 function Make_OK_Assignment_Statement
113 Expression
: Node_Id
) return Node_Id
;
114 -- This is like Make_Assignment_Statement, except that Assignment_OK
115 -- is set in the left operand. All assignments built by this unit use
116 -- this routine. This is needed to deal with assignments to initialized
117 -- constants that are done in place.
120 (Obj_Type
: Entity_Id
;
121 Typ
: Entity_Id
) return Boolean;
122 -- A static array aggregate in an object declaration can in most cases be
123 -- expanded in place. The one exception is when the aggregate is given
124 -- with component associations that specify different bounds from those of
125 -- the type definition in the object declaration. In this pathological
126 -- case the aggregate must slide, and we must introduce an intermediate
127 -- temporary to hold it.
129 -- The same holds in an assignment to one-dimensional array of arrays,
130 -- when a component may be given with bounds that differ from those of the
133 function Number_Of_Choices
(N
: Node_Id
) return Nat
;
134 -- Returns the number of discrete choices (not including the others choice
135 -- if present) contained in (sub-)aggregate N.
137 procedure Process_Transient_Component
139 Comp_Typ
: Entity_Id
;
141 Fin_Call
: out Node_Id
;
142 Hook_Clear
: out Node_Id
;
143 Aggr
: Node_Id
:= Empty
;
144 Stmts
: List_Id
:= No_List
);
145 -- Subsidiary to the expansion of array and record aggregates. Generate
146 -- part of the necessary code to finalize a transient component. Comp_Typ
147 -- is the component type. Init_Expr is the initialization expression of the
148 -- component which is always a function call. Fin_Call is the finalization
149 -- call used to clean up the transient function result. Hook_Clear is the
150 -- hook reset statement. Aggr and Stmts both control the placement of the
151 -- generated code. Aggr is the related aggregate. If present, all code is
152 -- inserted prior to Aggr using Insert_Action. Stmts is the initialization
153 -- statements of the component. If present, all code is added to Stmts.
155 procedure Process_Transient_Component_Completion
159 Hook_Clear
: Node_Id
;
161 -- Subsidiary to the expansion of array and record aggregates. Generate
162 -- part of the necessary code to finalize a transient component. Aggr is
163 -- the related aggregate. Fin_Clear is the finalization call used to clean
164 -- up the transient component. Hook_Clear is the hook reset statment. Stmts
165 -- is the initialization statement list for the component. All generated
166 -- code is added to Stmts.
168 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
);
169 -- Sort the Case Table using the Lower Bound of each Choice as the key.
170 -- A simple insertion sort is used since the number of choices in a case
171 -- statement of variant part will usually be small and probably in near
174 ------------------------------------------------------
175 -- Local subprograms for Record Aggregate Expansion --
176 ------------------------------------------------------
178 function Is_Build_In_Place_Aggregate_Return
(N
: Node_Id
) return Boolean;
179 -- True if N is an aggregate (possibly qualified or converted) that is
180 -- being returned from a build-in-place function.
182 function Build_Record_Aggr_Code
185 Lhs
: Node_Id
) return List_Id
;
186 -- N is an N_Aggregate or an N_Extension_Aggregate. Typ is the type of the
187 -- aggregate. Target is an expression containing the location on which the
188 -- component by component assignments will take place. Returns the list of
189 -- assignments plus all other adjustments needed for tagged and controlled
192 procedure Convert_To_Assignments
(N
: Node_Id
; Typ
: Entity_Id
);
193 -- Transform a record aggregate into a sequence of assignments performed
194 -- component by component. N is an N_Aggregate or N_Extension_Aggregate.
195 -- Typ is the type of the record aggregate.
197 procedure Expand_Record_Aggregate
199 Orig_Tag
: Node_Id
:= Empty
;
200 Parent_Expr
: Node_Id
:= Empty
);
201 -- This is the top level procedure for record aggregate expansion.
202 -- Expansion for record aggregates needs expand aggregates for tagged
203 -- record types. Specifically Expand_Record_Aggregate adds the Tag
204 -- field in front of the Component_Association list that was created
205 -- during resolution by Resolve_Record_Aggregate.
207 -- N is the record aggregate node.
208 -- Orig_Tag is the value of the Tag that has to be provided for this
209 -- specific aggregate. It carries the tag corresponding to the type
210 -- of the outermost aggregate during the recursive expansion
211 -- Parent_Expr is the ancestor part of the original extension
214 function Has_Mutable_Components
(Typ
: Entity_Id
) return Boolean;
215 -- Return true if one of the components is of a discriminated type with
216 -- defaults. An aggregate for a type with mutable components must be
217 -- expanded into individual assignments.
219 procedure Initialize_Discriminants
(N
: Node_Id
; Typ
: Entity_Id
);
220 -- If the type of the aggregate is a type extension with renamed discrimi-
221 -- nants, we must initialize the hidden discriminants of the parent.
222 -- Otherwise, the target object must not be initialized. The discriminants
223 -- are initialized by calling the initialization procedure for the type.
224 -- This is incorrect if the initialization of other components has any
225 -- side effects. We restrict this call to the case where the parent type
226 -- has a variant part, because this is the only case where the hidden
227 -- discriminants are accessed, namely when calling discriminant checking
228 -- functions of the parent type, and when applying a stream attribute to
229 -- an object of the derived type.
231 -----------------------------------------------------
232 -- Local Subprograms for Array Aggregate Expansion --
233 -----------------------------------------------------
235 function Aggr_Size_OK
(N
: Node_Id
; Typ
: Entity_Id
) return Boolean;
236 -- Very large static aggregates present problems to the back-end, and are
237 -- transformed into assignments and loops. This function verifies that the
238 -- total number of components of an aggregate is acceptable for rewriting
239 -- into a purely positional static form. Aggr_Size_OK must be called before
242 -- This function also detects and warns about one-component aggregates that
243 -- appear in a nonstatic context. Even if the component value is static,
244 -- such an aggregate must be expanded into an assignment.
246 function Backend_Processing_Possible
(N
: Node_Id
) return Boolean;
247 -- This function checks if array aggregate N can be processed directly
248 -- by the backend. If this is the case, True is returned.
250 function Build_Array_Aggr_Code
255 Scalar_Comp
: Boolean;
256 Indexes
: List_Id
:= No_List
) return List_Id
;
257 -- This recursive routine returns a list of statements containing the
258 -- loops and assignments that are needed for the expansion of the array
261 -- N is the (sub-)aggregate node to be expanded into code. This node has
262 -- been fully analyzed, and its Etype is properly set.
264 -- Index is the index node corresponding to the array subaggregate N
266 -- Into is the target expression into which we are copying the aggregate.
267 -- Note that this node may not have been analyzed yet, and so the Etype
268 -- field may not be set.
270 -- Scalar_Comp is True if the component type of the aggregate is scalar
272 -- Indexes is the current list of expressions used to index the object we
275 procedure Convert_Array_Aggr_In_Allocator
279 -- If the aggregate appears within an allocator and can be expanded in
280 -- place, this routine generates the individual assignments to components
281 -- of the designated object. This is an optimization over the general
282 -- case, where a temporary is first created on the stack and then used to
283 -- construct the allocated object on the heap.
285 procedure Convert_To_Positional
287 Max_Others_Replicate
: Nat
:= 32;
288 Handle_Bit_Packed
: Boolean := False);
289 -- If possible, convert named notation to positional notation. This
290 -- conversion is possible only in some static cases. If the conversion is
291 -- possible, then N is rewritten with the analyzed converted aggregate.
292 -- The parameter Max_Others_Replicate controls the maximum number of
293 -- values corresponding to an others choice that will be converted to
294 -- positional notation (the default of 32 is the normal limit, and reflects
295 -- the fact that normally the loop is better than a lot of separate
296 -- assignments). Note that this limit gets overridden in any case if
297 -- either of the restrictions No_Elaboration_Code or No_Implicit_Loops is
298 -- set. The parameter Handle_Bit_Packed is usually set False (since we do
299 -- not expect the back end to handle bit packed arrays, so the normal case
300 -- of conversion is pointless), but in the special case of a call from
301 -- Packed_Array_Aggregate_Handled, we set this parameter to True, since
302 -- these are cases we handle in there.
304 procedure Expand_Array_Aggregate
(N
: Node_Id
);
305 -- This is the top-level routine to perform array aggregate expansion.
306 -- N is the N_Aggregate node to be expanded.
308 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean;
309 -- For two-dimensional packed aggregates with constant bounds and constant
310 -- components, it is preferable to pack the inner aggregates because the
311 -- whole matrix can then be presented to the back-end as a one-dimensional
312 -- list of literals. This is much more efficient than expanding into single
313 -- component assignments. This function determines if the type Typ is for
314 -- an array that is suitable for this optimization: it returns True if Typ
315 -- is a two dimensional bit packed array with component size 1, 2, or 4.
317 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean;
318 -- Given an array aggregate, this function handles the case of a packed
319 -- array aggregate with all constant values, where the aggregate can be
320 -- evaluated at compile time. If this is possible, then N is rewritten
321 -- to be its proper compile time value with all the components properly
322 -- assembled. The expression is analyzed and resolved and True is returned.
323 -- If this transformation is not possible, N is unchanged and False is
326 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean;
327 -- If the type of the aggregate is a two-dimensional bit_packed array
328 -- it may be transformed into an array of bytes with constant values,
329 -- and presented to the back-end as a static value. The function returns
330 -- false if this transformation cannot be performed. THis is similar to,
331 -- and reuses part of the machinery in Packed_Array_Aggregate_Handled.
337 function Aggr_Size_OK
(N
: Node_Id
; Typ
: Entity_Id
) return Boolean is
346 -- Determines the maximum size of an array aggregate produced by
347 -- converting named to positional notation (e.g. from others clauses).
348 -- This avoids running away with attempts to convert huge aggregates,
349 -- which hit memory limits in the backend.
351 function Component_Count
(T
: Entity_Id
) return Nat
;
352 -- The limit is applied to the total number of subcomponents that the
353 -- aggregate will have, which is the number of static expressions
354 -- that will appear in the flattened array. This requires a recursive
355 -- computation of the number of scalar components of the structure.
357 ---------------------
358 -- Component_Count --
359 ---------------------
361 function Component_Count
(T
: Entity_Id
) return Nat
is
366 if Is_Scalar_Type
(T
) then
369 elsif Is_Record_Type
(T
) then
370 Comp
:= First_Component
(T
);
371 while Present
(Comp
) loop
372 Res
:= Res
+ Component_Count
(Etype
(Comp
));
373 Next_Component
(Comp
);
378 elsif Is_Array_Type
(T
) then
380 Lo
: constant Node_Id
:=
381 Type_Low_Bound
(Etype
(First_Index
(T
)));
382 Hi
: constant Node_Id
:=
383 Type_High_Bound
(Etype
(First_Index
(T
)));
385 Siz
: constant Nat
:= Component_Count
(Component_Type
(T
));
388 -- Check for superflat arrays, i.e. arrays with such bounds
389 -- as 4 .. 2, to insure that this function never returns a
390 -- meaningless negative value.
392 if not Compile_Time_Known_Value
(Lo
)
393 or else not Compile_Time_Known_Value
(Hi
)
394 or else Expr_Value
(Hi
) < Expr_Value
(Lo
)
399 -- If the number of components is greater than Int'Last,
400 -- then return Int'Last, so caller will return False (Aggr
401 -- size is not OK). Otherwise, UI_To_Int will crash.
404 UI
: constant Uint
:=
405 Expr_Value
(Hi
) - Expr_Value
(Lo
) + 1;
407 if UI_Is_In_Int_Range
(UI
) then
408 return Siz
* UI_To_Int
(UI
);
417 -- Can only be a null for an access type
423 -- Start of processing for Aggr_Size_OK
426 -- The normal aggregate limit is 500000, but we increase this limit to
427 -- 2**24 (about 16 million) if Restrictions (No_Elaboration_Code) or
428 -- Restrictions (No_Implicit_Loops) is specified, since in either case
429 -- we are at risk of declaring the program illegal because of this
430 -- limit. We also increase the limit when Static_Elaboration_Desired,
431 -- given that this means that objects are intended to be placed in data
434 -- We also increase the limit if the aggregate is for a packed two-
435 -- dimensional array, because if components are static it is much more
436 -- efficient to construct a one-dimensional equivalent array with static
439 -- Conversely, we decrease the maximum size if none of the above
440 -- requirements apply, and if the aggregate has a single component
441 -- association, which will be more efficient if implemented with a loop.
443 -- Finally, we use a small limit in CodePeer mode where we favor loops
444 -- instead of thousands of single assignments (from large aggregates).
446 Max_Aggr_Size
:= 500000;
448 if CodePeer_Mode
then
449 Max_Aggr_Size
:= 100;
451 elsif Restriction_Active
(No_Elaboration_Code
)
452 or else Restriction_Active
(No_Implicit_Loops
)
453 or else Is_Two_Dim_Packed_Array
(Typ
)
454 or else (Ekind
(Current_Scope
) = E_Package
455 and then Static_Elaboration_Desired
(Current_Scope
))
457 Max_Aggr_Size
:= 2 ** 24;
459 elsif No
(Expressions
(N
))
460 and then No
(Next
(First
(Component_Associations
(N
))))
462 Max_Aggr_Size
:= 5000;
465 Siz
:= Component_Count
(Component_Type
(Typ
));
467 Indx
:= First_Index
(Typ
);
468 while Present
(Indx
) loop
469 Lo
:= Type_Low_Bound
(Etype
(Indx
));
470 Hi
:= Type_High_Bound
(Etype
(Indx
));
472 -- Bounds need to be known at compile time
474 if not Compile_Time_Known_Value
(Lo
)
475 or else not Compile_Time_Known_Value
(Hi
)
480 Lov
:= Expr_Value
(Lo
);
481 Hiv
:= Expr_Value
(Hi
);
483 -- A flat array is always safe
489 -- One-component aggregates are suspicious, and if the context type
490 -- is an object declaration with nonstatic bounds it will trip gcc;
491 -- such an aggregate must be expanded into a single assignment.
493 if Hiv
= Lov
and then Nkind
(Parent
(N
)) = N_Object_Declaration
then
495 Index_Type
: constant Entity_Id
:=
497 (First_Index
(Etype
(Defining_Identifier
(Parent
(N
)))));
501 if not Compile_Time_Known_Value
(Type_Low_Bound
(Index_Type
))
502 or else not Compile_Time_Known_Value
503 (Type_High_Bound
(Index_Type
))
505 if Present
(Component_Associations
(N
)) then
508 (Choice_List
(First
(Component_Associations
(N
))));
510 if Is_Entity_Name
(Indx
)
511 and then not Is_Type
(Entity
(Indx
))
514 ("single component aggregate in "
515 & "non-static context??", Indx
);
516 Error_Msg_N
("\maybe subtype name was meant??", Indx
);
526 Rng
: constant Uint
:= Hiv
- Lov
+ 1;
529 -- Check if size is too large
531 if not UI_Is_In_Int_Range
(Rng
) then
535 Siz
:= Siz
* UI_To_Int
(Rng
);
539 or else Siz
> Max_Aggr_Size
544 -- Bounds must be in integer range, for later array construction
546 if not UI_Is_In_Int_Range
(Lov
)
548 not UI_Is_In_Int_Range
(Hiv
)
559 ---------------------------------
560 -- Backend_Processing_Possible --
561 ---------------------------------
563 -- Backend processing by Gigi/gcc is possible only if all the following
564 -- conditions are met:
566 -- 1. N is fully positional
568 -- 2. N is not a bit-packed array aggregate;
570 -- 3. The size of N's array type must be known at compile time. Note
571 -- that this implies that the component size is also known
573 -- 4. The array type of N does not follow the Fortran layout convention
574 -- or if it does it must be 1 dimensional.
576 -- 5. The array component type may not be tagged (which could necessitate
577 -- reassignment of proper tags).
579 -- 6. The array component type must not have unaligned bit components
581 -- 7. None of the components of the aggregate may be bit unaligned
584 -- 8. There cannot be delayed components, since we do not know enough
585 -- at this stage to know if back end processing is possible.
587 -- 9. There cannot be any discriminated record components, since the
588 -- back end cannot handle this complex case.
590 -- 10. No controlled actions need to be generated for components
592 -- 11. When generating C code, N must be part of a N_Object_Declaration
594 -- 12. When generating C code, N must not include function calls
596 function Backend_Processing_Possible
(N
: Node_Id
) return Boolean is
597 Typ
: constant Entity_Id
:= Etype
(N
);
598 -- Typ is the correct constrained array subtype of the aggregate
600 function Component_Check
(N
: Node_Id
; Index
: Node_Id
) return Boolean;
601 -- This routine checks components of aggregate N, enforcing checks
602 -- 1, 7, 8, 9, 11, and 12. In the multidimensional case, these checks
603 -- are performed on subaggregates. The Index value is the current index
604 -- being checked in the multidimensional case.
606 ---------------------
607 -- Component_Check --
608 ---------------------
610 function Component_Check
(N
: Node_Id
; Index
: Node_Id
) return Boolean is
611 function Ultimate_Original_Expression
(N
: Node_Id
) return Node_Id
;
612 -- Given a type conversion or an unchecked type conversion N, return
613 -- its innermost original expression.
615 ----------------------------------
616 -- Ultimate_Original_Expression --
617 ----------------------------------
619 function Ultimate_Original_Expression
(N
: Node_Id
) return Node_Id
is
620 Expr
: Node_Id
:= Original_Node
(N
);
623 while Nkind_In
(Expr
, N_Type_Conversion
,
624 N_Unchecked_Type_Conversion
)
626 Expr
:= Original_Node
(Expression
(Expr
));
630 end Ultimate_Original_Expression
;
636 -- Start of processing for Component_Check
639 -- Checks 1: (no component associations)
641 if Present
(Component_Associations
(N
)) then
645 -- Checks 11: The C code generator cannot handle aggregates that are
646 -- not part of an object declaration.
648 if Modify_Tree_For_C
then
650 Par
: Node_Id
:= Parent
(N
);
653 -- Skip enclosing nested aggregates and their qualified
656 while Nkind
(Par
) = N_Aggregate
657 or else Nkind
(Par
) = N_Qualified_Expression
662 if Nkind
(Par
) /= N_Object_Declaration
then
668 -- Checks on components
670 -- Recurse to check subaggregates, which may appear in qualified
671 -- expressions. If delayed, the front-end will have to expand.
672 -- If the component is a discriminated record, treat as nonstatic,
673 -- as the back-end cannot handle this properly.
675 Expr
:= First
(Expressions
(N
));
676 while Present
(Expr
) loop
678 -- Checks 8: (no delayed components)
680 if Is_Delayed_Aggregate
(Expr
) then
684 -- Checks 9: (no discriminated records)
686 if Present
(Etype
(Expr
))
687 and then Is_Record_Type
(Etype
(Expr
))
688 and then Has_Discriminants
(Etype
(Expr
))
693 -- Checks 7. Component must not be bit aligned component
695 if Possible_Bit_Aligned_Component
(Expr
) then
699 -- Checks 12: (no function call)
703 Nkind
(Ultimate_Original_Expression
(Expr
)) = N_Function_Call
708 -- Recursion to following indexes for multiple dimension case
710 if Present
(Next_Index
(Index
))
711 and then not Component_Check
(Expr
, Next_Index
(Index
))
716 -- All checks for that component finished, on to next
724 -- Start of processing for Backend_Processing_Possible
727 -- Checks 2 (array not bit packed) and 10 (no controlled actions)
729 if Is_Bit_Packed_Array
(Typ
) or else Needs_Finalization
(Typ
) then
733 -- If component is limited, aggregate must be expanded because each
734 -- component assignment must be built in place.
736 if Is_Limited_View
(Component_Type
(Typ
)) then
740 -- Checks 4 (array must not be multidimensional Fortran case)
742 if Convention
(Typ
) = Convention_Fortran
743 and then Number_Dimensions
(Typ
) > 1
748 -- Checks 3 (size of array must be known at compile time)
750 if not Size_Known_At_Compile_Time
(Typ
) then
754 -- Checks on components
756 if not Component_Check
(N
, First_Index
(Typ
)) then
760 -- Checks 5 (if the component type is tagged, then we may need to do
761 -- tag adjustments. Perhaps this should be refined to check for any
762 -- component associations that actually need tag adjustment, similar
763 -- to the test in Component_OK_For_Backend for record aggregates with
764 -- tagged components, but not clear whether it's worthwhile ???; in the
765 -- case of virtual machines (no Tagged_Type_Expansion), object tags are
766 -- handled implicitly).
768 if Is_Tagged_Type
(Component_Type
(Typ
))
769 and then Tagged_Type_Expansion
774 -- Checks 6 (component type must not have bit aligned components)
776 if Type_May_Have_Bit_Aligned_Components
(Component_Type
(Typ
)) then
780 -- Backend processing is possible
782 Set_Size_Known_At_Compile_Time
(Etype
(N
), True);
784 end Backend_Processing_Possible
;
786 ---------------------------
787 -- Build_Array_Aggr_Code --
788 ---------------------------
790 -- The code that we generate from a one dimensional aggregate is
792 -- 1. If the subaggregate contains discrete choices we
794 -- (a) Sort the discrete choices
796 -- (b) Otherwise for each discrete choice that specifies a range we
797 -- emit a loop. If a range specifies a maximum of three values, or
798 -- we are dealing with an expression we emit a sequence of
799 -- assignments instead of a loop.
801 -- (c) Generate the remaining loops to cover the others choice if any
803 -- 2. If the aggregate contains positional elements we
805 -- (a) translate the positional elements in a series of assignments
807 -- (b) Generate a final loop to cover the others choice if any.
808 -- Note that this final loop has to be a while loop since the case
810 -- L : Integer := Integer'Last;
811 -- H : Integer := Integer'Last;
812 -- A : array (L .. H) := (1, others =>0);
814 -- cannot be handled by a for loop. Thus for the following
816 -- array (L .. H) := (.. positional elements.., others =>E);
818 -- we always generate something like:
820 -- J : Index_Type := Index_Of_Last_Positional_Element;
822 -- J := Index_Base'Succ (J)
826 function Build_Array_Aggr_Code
831 Scalar_Comp
: Boolean;
832 Indexes
: List_Id
:= No_List
) return List_Id
834 Loc
: constant Source_Ptr
:= Sloc
(N
);
835 Index_Base
: constant Entity_Id
:= Base_Type
(Etype
(Index
));
836 Index_Base_L
: constant Node_Id
:= Type_Low_Bound
(Index_Base
);
837 Index_Base_H
: constant Node_Id
:= Type_High_Bound
(Index_Base
);
839 function Add
(Val
: Int
; To
: Node_Id
) return Node_Id
;
840 -- Returns an expression where Val is added to expression To, unless
841 -- To+Val is provably out of To's base type range. To must be an
842 -- already analyzed expression.
844 function Empty_Range
(L
, H
: Node_Id
) return Boolean;
845 -- Returns True if the range defined by L .. H is certainly empty
847 function Equal
(L
, H
: Node_Id
) return Boolean;
848 -- Returns True if L = H for sure
850 function Index_Base_Name
return Node_Id
;
851 -- Returns a new reference to the index type name
856 In_Loop
: Boolean := False) return List_Id
;
857 -- Ind must be a side-effect-free expression. If the input aggregate N
858 -- to Build_Loop contains no subaggregates, then this function returns
859 -- the assignment statement:
861 -- Into (Indexes, Ind) := Expr;
863 -- Otherwise we call Build_Code recursively. Flag In_Loop should be set
864 -- when the assignment appears within a generated loop.
866 -- Ada 2005 (AI-287): In case of default initialized component, Expr
867 -- is empty and we generate a call to the corresponding IP subprogram.
869 function Gen_Loop
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
;
870 -- Nodes L and H must be side-effect-free expressions. If the input
871 -- aggregate N to Build_Loop contains no subaggregates, this routine
872 -- returns the for loop statement:
874 -- for J in Index_Base'(L) .. Index_Base'(H) loop
875 -- Into (Indexes, J) := Expr;
878 -- Otherwise we call Build_Code recursively. As an optimization if the
879 -- loop covers 3 or fewer scalar elements we generate a sequence of
881 -- If the component association that generates the loop comes from an
882 -- Iterated_Component_Association, the loop parameter has the name of
883 -- the corresponding parameter in the original construct.
885 function Gen_While
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
;
886 -- Nodes L and H must be side-effect-free expressions. If the input
887 -- aggregate N to Build_Loop contains no subaggregates, this routine
888 -- returns the while loop statement:
890 -- J : Index_Base := L;
892 -- J := Index_Base'Succ (J);
893 -- Into (Indexes, J) := Expr;
896 -- Otherwise we call Build_Code recursively
898 function Get_Assoc_Expr
(Assoc
: Node_Id
) return Node_Id
;
899 -- For an association with a box, use value given by aspect
900 -- Default_Component_Value of array type if specified, else use
901 -- value given by aspect Default_Value for component type itself
902 -- if specified, else return Empty.
904 function Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean;
905 function Local_Expr_Value
(E
: Node_Id
) return Uint
;
906 -- These two Local routines are used to replace the corresponding ones
907 -- in sem_eval because while processing the bounds of an aggregate with
908 -- discrete choices whose index type is an enumeration, we build static
909 -- expressions not recognized by Compile_Time_Known_Value as such since
910 -- they have not yet been analyzed and resolved. All the expressions in
911 -- question are things like Index_Base_Name'Val (Const) which we can
912 -- easily recognize as being constant.
918 function Add
(Val
: Int
; To
: Node_Id
) return Node_Id
is
923 U_Val
: constant Uint
:= UI_From_Int
(Val
);
926 -- Note: do not try to optimize the case of Val = 0, because
927 -- we need to build a new node with the proper Sloc value anyway.
929 -- First test if we can do constant folding
931 if Local_Compile_Time_Known_Value
(To
) then
932 U_To
:= Local_Expr_Value
(To
) + Val
;
934 -- Determine if our constant is outside the range of the index.
935 -- If so return an Empty node. This empty node will be caught
936 -- by Empty_Range below.
938 if Compile_Time_Known_Value
(Index_Base_L
)
939 and then U_To
< Expr_Value
(Index_Base_L
)
943 elsif Compile_Time_Known_Value
(Index_Base_H
)
944 and then U_To
> Expr_Value
(Index_Base_H
)
949 Expr_Pos
:= Make_Integer_Literal
(Loc
, U_To
);
950 Set_Is_Static_Expression
(Expr_Pos
);
952 if not Is_Enumeration_Type
(Index_Base
) then
955 -- If we are dealing with enumeration return
956 -- Index_Base'Val (Expr_Pos)
960 Make_Attribute_Reference
962 Prefix
=> Index_Base_Name
,
963 Attribute_Name
=> Name_Val
,
964 Expressions
=> New_List
(Expr_Pos
));
970 -- If we are here no constant folding possible
972 if not Is_Enumeration_Type
(Index_Base
) then
975 Left_Opnd
=> Duplicate_Subexpr
(To
),
976 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
978 -- If we are dealing with enumeration return
979 -- Index_Base'Val (Index_Base'Pos (To) + Val)
983 Make_Attribute_Reference
985 Prefix
=> Index_Base_Name
,
986 Attribute_Name
=> Name_Pos
,
987 Expressions
=> New_List
(Duplicate_Subexpr
(To
)));
992 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
995 Make_Attribute_Reference
997 Prefix
=> Index_Base_Name
,
998 Attribute_Name
=> Name_Val
,
999 Expressions
=> New_List
(Expr_Pos
));
1009 function Empty_Range
(L
, H
: Node_Id
) return Boolean is
1010 Is_Empty
: Boolean := False;
1015 -- First check if L or H were already detected as overflowing the
1016 -- index base range type by function Add above. If this is so Add
1017 -- returns the empty node.
1019 if No
(L
) or else No
(H
) then
1023 for J
in 1 .. 3 loop
1026 -- L > H range is empty
1032 -- B_L > H range must be empty
1035 Low
:= Index_Base_L
;
1038 -- L > B_H range must be empty
1042 High
:= Index_Base_H
;
1045 if Local_Compile_Time_Known_Value
(Low
)
1047 Local_Compile_Time_Known_Value
(High
)
1050 UI_Gt
(Local_Expr_Value
(Low
), Local_Expr_Value
(High
));
1063 function Equal
(L
, H
: Node_Id
) return Boolean is
1068 elsif Local_Compile_Time_Known_Value
(L
)
1070 Local_Compile_Time_Known_Value
(H
)
1072 return UI_Eq
(Local_Expr_Value
(L
), Local_Expr_Value
(H
));
1085 In_Loop
: Boolean := False) return List_Id
1087 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
;
1088 -- Collect insert_actions generated in the construction of a loop,
1089 -- and prepend them to the sequence of assignments to complete the
1090 -- eventual body of the loop.
1092 procedure Initialize_Array_Component
1093 (Arr_Comp
: Node_Id
;
1095 Init_Expr
: Node_Id
;
1097 -- Perform the initialization of array component Arr_Comp with
1098 -- expected type Comp_Typ. Init_Expr denotes the initialization
1099 -- expression of the array component. All generated code is added
1102 procedure Initialize_Ctrl_Array_Component
1103 (Arr_Comp
: Node_Id
;
1104 Comp_Typ
: Entity_Id
;
1105 Init_Expr
: Node_Id
;
1107 -- Perform the initialization of array component Arr_Comp when its
1108 -- expected type Comp_Typ needs finalization actions. Init_Expr is
1109 -- the initialization expression of the array component. All hook-
1110 -- related declarations are inserted prior to aggregate N. Remaining
1111 -- code is added to list Stmts.
1113 ----------------------
1114 -- Add_Loop_Actions --
1115 ----------------------
1117 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
is
1121 -- Ada 2005 (AI-287): Do nothing else in case of default
1122 -- initialized component.
1127 elsif Nkind
(Parent
(Expr
)) = N_Component_Association
1128 and then Present
(Loop_Actions
(Parent
(Expr
)))
1130 Append_List
(Lis
, Loop_Actions
(Parent
(Expr
)));
1131 Res
:= Loop_Actions
(Parent
(Expr
));
1132 Set_Loop_Actions
(Parent
(Expr
), No_List
);
1138 end Add_Loop_Actions
;
1140 --------------------------------
1141 -- Initialize_Array_Component --
1142 --------------------------------
1144 procedure Initialize_Array_Component
1145 (Arr_Comp
: Node_Id
;
1147 Init_Expr
: Node_Id
;
1150 Exceptions_OK
: constant Boolean :=
1151 not Restriction_Active
1152 (No_Exception_Propagation
);
1154 Finalization_OK
: constant Boolean :=
1156 and then Needs_Finalization
(Comp_Typ
);
1158 Full_Typ
: constant Entity_Id
:= Underlying_Type
(Comp_Typ
);
1160 Blk_Stmts
: List_Id
;
1161 Init_Stmt
: Node_Id
;
1164 -- Protect the initialization statements from aborts. Generate:
1168 if Finalization_OK
and Abort_Allowed
then
1169 if Exceptions_OK
then
1170 Blk_Stmts
:= New_List
;
1175 Append_To
(Blk_Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
1177 -- Otherwise aborts are not allowed. All generated code is added
1178 -- directly to the input list.
1184 -- Initialize the array element. Generate:
1186 -- Arr_Comp := Init_Expr;
1188 -- Note that the initialization expression is replicated because
1189 -- it has to be reevaluated within a generated loop.
1192 Make_OK_Assignment_Statement
(Loc
,
1193 Name
=> New_Copy_Tree
(Arr_Comp
),
1194 Expression
=> New_Copy_Tree
(Init_Expr
));
1195 Set_No_Ctrl_Actions
(Init_Stmt
);
1197 -- If this is an aggregate for an array of arrays, each
1198 -- subaggregate will be expanded as well, and even with
1199 -- No_Ctrl_Actions the assignments of inner components will
1200 -- require attachment in their assignments to temporaries. These
1201 -- temporaries must be finalized for each subaggregate. Generate:
1204 -- Arr_Comp := Init_Expr;
1207 if Finalization_OK
and then Is_Array_Type
(Comp_Typ
) then
1209 Make_Block_Statement
(Loc
,
1210 Handled_Statement_Sequence
=>
1211 Make_Handled_Sequence_Of_Statements
(Loc
,
1212 Statements
=> New_List
(Init_Stmt
)));
1215 Append_To
(Blk_Stmts
, Init_Stmt
);
1217 -- Adjust the tag due to a possible view conversion. Generate:
1219 -- Arr_Comp._tag := Full_TypP;
1221 if Tagged_Type_Expansion
1222 and then Present
(Comp_Typ
)
1223 and then Is_Tagged_Type
(Comp_Typ
)
1225 Append_To
(Blk_Stmts
,
1226 Make_OK_Assignment_Statement
(Loc
,
1228 Make_Selected_Component
(Loc
,
1229 Prefix
=> New_Copy_Tree
(Arr_Comp
),
1232 (First_Tag_Component
(Full_Typ
), Loc
)),
1235 Unchecked_Convert_To
(RTE
(RE_Tag
),
1237 (Node
(First_Elmt
(Access_Disp_Table
(Full_Typ
))),
1241 -- Adjust the array component. Controlled subaggregates are not
1242 -- considered because each of their individual elements will
1243 -- receive an adjustment of its own. Generate:
1245 -- [Deep_]Adjust (Arr_Comp);
1248 and then not Is_Limited_Type
(Comp_Typ
)
1249 and then not Is_Build_In_Place_Function_Call
(Init_Expr
)
1251 (Is_Array_Type
(Comp_Typ
)
1252 and then Is_Controlled
(Component_Type
(Comp_Typ
))
1253 and then Nkind
(Expr
) = N_Aggregate
)
1257 (Obj_Ref
=> New_Copy_Tree
(Arr_Comp
),
1260 -- Guard against a missing [Deep_]Adjust when the component
1261 -- type was not frozen properly.
1263 if Present
(Adj_Call
) then
1264 Append_To
(Blk_Stmts
, Adj_Call
);
1268 -- Complete the protection of the initialization statements
1270 if Finalization_OK
and Abort_Allowed
then
1272 -- Wrap the initialization statements in a block to catch a
1273 -- potential exception. Generate:
1277 -- Arr_Comp := Init_Expr;
1278 -- Arr_Comp._tag := Full_TypP;
1279 -- [Deep_]Adjust (Arr_Comp);
1281 -- Abort_Undefer_Direct;
1284 if Exceptions_OK
then
1286 Build_Abort_Undefer_Block
(Loc
,
1290 -- Otherwise exceptions are not propagated. Generate:
1293 -- Arr_Comp := Init_Expr;
1294 -- Arr_Comp._tag := Full_TypP;
1295 -- [Deep_]Adjust (Arr_Comp);
1299 Append_To
(Blk_Stmts
,
1300 Build_Runtime_Call
(Loc
, RE_Abort_Undefer
));
1303 end Initialize_Array_Component
;
1305 -------------------------------------
1306 -- Initialize_Ctrl_Array_Component --
1307 -------------------------------------
1309 procedure Initialize_Ctrl_Array_Component
1310 (Arr_Comp
: Node_Id
;
1311 Comp_Typ
: Entity_Id
;
1312 Init_Expr
: Node_Id
;
1316 Act_Stmts
: List_Id
;
1319 Hook_Clear
: Node_Id
;
1321 In_Place_Expansion
: Boolean;
1322 -- Flag set when a nonlimited controlled function call requires
1323 -- in-place expansion.
1326 -- Duplicate the initialization expression in case the context is
1327 -- a multi choice list or an "others" choice which plugs various
1328 -- holes in the aggregate. As a result the expression is no longer
1329 -- shared between the various components and is reevaluated for
1330 -- each such component.
1332 Expr
:= New_Copy_Tree
(Init_Expr
);
1333 Set_Parent
(Expr
, Parent
(Init_Expr
));
1335 -- Perform a preliminary analysis and resolution to determine what
1336 -- the initialization expression denotes. An unanalyzed function
1337 -- call may appear as an identifier or an indexed component.
1339 if Nkind_In
(Expr
, N_Function_Call
,
1341 N_Indexed_Component
)
1342 and then not Analyzed
(Expr
)
1344 Preanalyze_And_Resolve
(Expr
, Comp_Typ
);
1347 In_Place_Expansion
:=
1348 Nkind
(Expr
) = N_Function_Call
1349 and then not Is_Build_In_Place_Result_Type
(Comp_Typ
);
1351 -- The initialization expression is a controlled function call.
1352 -- Perform in-place removal of side effects to avoid creating a
1353 -- transient scope, which leads to premature finalization.
1355 -- This in-place expansion is not performed for limited transient
1356 -- objects because the initialization is already done in-place.
1358 if In_Place_Expansion
then
1360 -- Suppress the removal of side effects by general analysis
1361 -- because this behavior is emulated here. This avoids the
1362 -- generation of a transient scope, which leads to out-of-order
1363 -- adjustment and finalization.
1365 Set_No_Side_Effect_Removal
(Expr
);
1367 -- When the transient component initialization is related to a
1368 -- range or an "others", keep all generated statements within
1369 -- the enclosing loop. This way the controlled function call
1370 -- will be evaluated at each iteration, and its result will be
1371 -- finalized at the end of each iteration.
1377 -- Otherwise this is a single component initialization. Hook-
1378 -- related statements are inserted prior to the aggregate.
1382 Act_Stmts
:= No_List
;
1385 -- Install all hook-related declarations and prepare the clean
1388 Process_Transient_Component
1390 Comp_Typ
=> Comp_Typ
,
1392 Fin_Call
=> Fin_Call
,
1393 Hook_Clear
=> Hook_Clear
,
1395 Stmts
=> Act_Stmts
);
1398 -- Use the noncontrolled component initialization circuitry to
1399 -- assign the result of the function call to the array element.
1400 -- This also performs subaggregate wrapping, tag adjustment, and
1401 -- [deep] adjustment of the array element.
1403 Initialize_Array_Component
1404 (Arr_Comp
=> Arr_Comp
,
1405 Comp_Typ
=> Comp_Typ
,
1409 -- At this point the array element is fully initialized. Complete
1410 -- the processing of the controlled array component by finalizing
1411 -- the transient function result.
1413 if In_Place_Expansion
then
1414 Process_Transient_Component_Completion
1417 Fin_Call
=> Fin_Call
,
1418 Hook_Clear
=> Hook_Clear
,
1421 end Initialize_Ctrl_Array_Component
;
1425 Stmts
: constant List_Id
:= New_List
;
1427 Comp_Typ
: Entity_Id
:= Empty
;
1429 Indexed_Comp
: Node_Id
;
1430 Init_Call
: Node_Id
;
1431 New_Indexes
: List_Id
;
1433 -- Start of processing for Gen_Assign
1436 if No
(Indexes
) then
1437 New_Indexes
:= New_List
;
1439 New_Indexes
:= New_Copy_List_Tree
(Indexes
);
1442 Append_To
(New_Indexes
, Ind
);
1444 if Present
(Next_Index
(Index
)) then
1447 Build_Array_Aggr_Code
1450 Index
=> Next_Index
(Index
),
1452 Scalar_Comp
=> Scalar_Comp
,
1453 Indexes
=> New_Indexes
));
1456 -- If we get here then we are at a bottom-level (sub-)aggregate
1460 (Make_Indexed_Component
(Loc
,
1461 Prefix
=> New_Copy_Tree
(Into
),
1462 Expressions
=> New_Indexes
));
1464 Set_Assignment_OK
(Indexed_Comp
);
1466 -- Ada 2005 (AI-287): In case of default initialized component, Expr
1467 -- is not present (and therefore we also initialize Expr_Q to empty).
1471 elsif Nkind
(Expr
) = N_Qualified_Expression
then
1472 Expr_Q
:= Expression
(Expr
);
1477 if Present
(Etype
(N
)) and then Etype
(N
) /= Any_Composite
then
1478 Comp_Typ
:= Component_Type
(Etype
(N
));
1479 pragma Assert
(Comp_Typ
= Ctype
); -- AI-287
1481 elsif Present
(Next
(First
(New_Indexes
))) then
1483 -- Ada 2005 (AI-287): Do nothing in case of default initialized
1484 -- component because we have received the component type in
1485 -- the formal parameter Ctype.
1487 -- ??? Some assert pragmas have been added to check if this new
1488 -- formal can be used to replace this code in all cases.
1490 if Present
(Expr
) then
1492 -- This is a multidimensional array. Recover the component type
1493 -- from the outermost aggregate, because subaggregates do not
1494 -- have an assigned type.
1501 while Present
(P
) loop
1502 if Nkind
(P
) = N_Aggregate
1503 and then Present
(Etype
(P
))
1505 Comp_Typ
:= Component_Type
(Etype
(P
));
1513 pragma Assert
(Comp_Typ
= Ctype
); -- AI-287
1518 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
1519 -- default initialized components (otherwise Expr_Q is not present).
1522 and then Nkind_In
(Expr_Q
, N_Aggregate
, N_Extension_Aggregate
)
1524 -- At this stage the Expression may not have been analyzed yet
1525 -- because the array aggregate code has not been updated to use
1526 -- the Expansion_Delayed flag and avoid analysis altogether to
1527 -- solve the same problem (see Resolve_Aggr_Expr). So let us do
1528 -- the analysis of non-array aggregates now in order to get the
1529 -- value of Expansion_Delayed flag for the inner aggregate ???
1531 -- In the case of an iterated component association, the analysis
1532 -- of the generated loop will analyze the expression in the
1533 -- proper context, in which the loop parameter is visible.
1535 if Present
(Comp_Typ
) and then not Is_Array_Type
(Comp_Typ
) then
1536 if Nkind
(Parent
(Expr_Q
)) = N_Iterated_Component_Association
1537 or else Nkind
(Parent
(Parent
((Expr_Q
)))) =
1538 N_Iterated_Component_Association
1542 Analyze_And_Resolve
(Expr_Q
, Comp_Typ
);
1546 if Is_Delayed_Aggregate
(Expr_Q
) then
1548 -- This is either a subaggregate of a multidimensional array,
1549 -- or a component of an array type whose component type is
1550 -- also an array. In the latter case, the expression may have
1551 -- component associations that provide different bounds from
1552 -- those of the component type, and sliding must occur. Instead
1553 -- of decomposing the current aggregate assignment, force the
1554 -- reanalysis of the assignment, so that a temporary will be
1555 -- generated in the usual fashion, and sliding will take place.
1557 if Nkind
(Parent
(N
)) = N_Assignment_Statement
1558 and then Is_Array_Type
(Comp_Typ
)
1559 and then Present
(Component_Associations
(Expr_Q
))
1560 and then Must_Slide
(Comp_Typ
, Etype
(Expr_Q
))
1562 Set_Expansion_Delayed
(Expr_Q
, False);
1563 Set_Analyzed
(Expr_Q
, False);
1568 Late_Expansion
(Expr_Q
, Etype
(Expr_Q
), Indexed_Comp
));
1573 if Present
(Expr
) then
1575 -- Handle an initialization expression of a controlled type in
1576 -- case it denotes a function call. In general such a scenario
1577 -- will produce a transient scope, but this will lead to wrong
1578 -- order of initialization, adjustment, and finalization in the
1579 -- context of aggregates.
1581 -- Target (1) := Ctrl_Func_Call;
1584 -- Trans_Obj : ... := Ctrl_Func_Call; -- object
1585 -- Target (1) := Trans_Obj;
1586 -- Finalize (Trans_Obj);
1588 -- Target (1)._tag := ...;
1589 -- Adjust (Target (1));
1591 -- In the example above, the call to Finalize occurs too early
1592 -- and as a result it may leave the array component in a bad
1593 -- state. Finalization of the transient object should really
1594 -- happen after adjustment.
1596 -- To avoid this scenario, perform in-place side-effect removal
1597 -- of the function call. This eliminates the transient property
1598 -- of the function result and ensures correct order of actions.
1600 -- Res : ... := Ctrl_Func_Call;
1601 -- Target (1) := Res;
1602 -- Target (1)._tag := ...;
1603 -- Adjust (Target (1));
1606 if Present
(Comp_Typ
)
1607 and then Needs_Finalization
(Comp_Typ
)
1608 and then Nkind
(Expr
) /= N_Aggregate
1610 Initialize_Ctrl_Array_Component
1611 (Arr_Comp
=> Indexed_Comp
,
1612 Comp_Typ
=> Comp_Typ
,
1616 -- Otherwise perform simple component initialization
1619 Initialize_Array_Component
1620 (Arr_Comp
=> Indexed_Comp
,
1621 Comp_Typ
=> Comp_Typ
,
1626 -- Ada 2005 (AI-287): In case of default initialized component, call
1627 -- the initialization subprogram associated with the component type.
1628 -- If the component type is an access type, add an explicit null
1629 -- assignment, because for the back-end there is an initialization
1630 -- present for the whole aggregate, and no default initialization
1633 -- In addition, if the component type is controlled, we must call
1634 -- its Initialize procedure explicitly, because there is no explicit
1635 -- object creation that will invoke it otherwise.
1638 if Present
(Base_Init_Proc
(Base_Type
(Ctype
)))
1639 or else Has_Task
(Base_Type
(Ctype
))
1641 Append_List_To
(Stmts
,
1642 Build_Initialization_Call
(Loc
,
1643 Id_Ref
=> Indexed_Comp
,
1645 With_Default_Init
=> True));
1647 -- If the component type has invariants, add an invariant
1648 -- check after the component is default-initialized. It will
1649 -- be analyzed and resolved before the code for initialization
1650 -- of other components.
1652 if Has_Invariants
(Ctype
) then
1653 Set_Etype
(Indexed_Comp
, Ctype
);
1654 Append_To
(Stmts
, Make_Invariant_Call
(Indexed_Comp
));
1657 elsif Is_Access_Type
(Ctype
) then
1659 Make_Assignment_Statement
(Loc
,
1660 Name
=> New_Copy_Tree
(Indexed_Comp
),
1661 Expression
=> Make_Null
(Loc
)));
1664 if Needs_Finalization
(Ctype
) then
1667 (Obj_Ref
=> New_Copy_Tree
(Indexed_Comp
),
1670 -- Guard against a missing [Deep_]Initialize when the component
1671 -- type was not properly frozen.
1673 if Present
(Init_Call
) then
1674 Append_To
(Stmts
, Init_Call
);
1679 return Add_Loop_Actions
(Stmts
);
1686 function Gen_Loop
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1687 Is_Iterated_Component
: constant Boolean :=
1688 Nkind
(Parent
(Expr
)) = N_Iterated_Component_Association
;
1699 -- Index_Base'(L) .. Index_Base'(H)
1701 L_Iteration_Scheme
: Node_Id
;
1702 -- L_J in Index_Base'(L) .. Index_Base'(H)
1705 -- The statements to execute in the loop
1707 S
: constant List_Id
:= New_List
;
1708 -- List of statements
1711 -- Copy of expression tree, used for checking purposes
1714 -- If loop bounds define an empty range return the null statement
1716 if Empty_Range
(L
, H
) then
1717 Append_To
(S
, Make_Null_Statement
(Loc
));
1719 -- Ada 2005 (AI-287): Nothing else need to be done in case of
1720 -- default initialized component.
1726 -- The expression must be type-checked even though no component
1727 -- of the aggregate will have this value. This is done only for
1728 -- actual components of the array, not for subaggregates. Do
1729 -- the check on a copy, because the expression may be shared
1730 -- among several choices, some of which might be non-null.
1732 if Present
(Etype
(N
))
1733 and then Is_Array_Type
(Etype
(N
))
1734 and then No
(Next_Index
(Index
))
1736 Expander_Mode_Save_And_Set
(False);
1737 Tcopy
:= New_Copy_Tree
(Expr
);
1738 Set_Parent
(Tcopy
, N
);
1739 Analyze_And_Resolve
(Tcopy
, Component_Type
(Etype
(N
)));
1740 Expander_Mode_Restore
;
1746 -- If loop bounds are the same then generate an assignment, unless
1747 -- the parent construct is an Iterated_Component_Association.
1749 elsif Equal
(L
, H
) and then not Is_Iterated_Component
then
1750 return Gen_Assign
(New_Copy_Tree
(L
), Expr
);
1752 -- If H - L <= 2 then generate a sequence of assignments when we are
1753 -- processing the bottom most aggregate and it contains scalar
1756 elsif No
(Next_Index
(Index
))
1757 and then Scalar_Comp
1758 and then Local_Compile_Time_Known_Value
(L
)
1759 and then Local_Compile_Time_Known_Value
(H
)
1760 and then Local_Expr_Value
(H
) - Local_Expr_Value
(L
) <= 2
1761 and then not Is_Iterated_Component
1763 Append_List_To
(S
, Gen_Assign
(New_Copy_Tree
(L
), Expr
));
1764 Append_List_To
(S
, Gen_Assign
(Add
(1, To
=> L
), Expr
));
1766 if Local_Expr_Value
(H
) - Local_Expr_Value
(L
) = 2 then
1767 Append_List_To
(S
, Gen_Assign
(Add
(2, To
=> L
), Expr
));
1773 -- Otherwise construct the loop, starting with the loop index L_J
1775 if Is_Iterated_Component
then
1777 Make_Defining_Identifier
(Loc
,
1778 Chars
=> (Chars
(Defining_Identifier
(Parent
(Expr
)))));
1781 L_J
:= Make_Temporary
(Loc
, 'J', L
);
1784 -- Construct "L .. H" in Index_Base. We use a qualified expression
1785 -- for the bound to convert to the index base, but we don't need
1786 -- to do that if we already have the base type at hand.
1788 if Etype
(L
) = Index_Base
then
1792 Make_Qualified_Expression
(Loc
,
1793 Subtype_Mark
=> Index_Base_Name
,
1794 Expression
=> New_Copy_Tree
(L
));
1797 if Etype
(H
) = Index_Base
then
1801 Make_Qualified_Expression
(Loc
,
1802 Subtype_Mark
=> Index_Base_Name
,
1803 Expression
=> New_Copy_Tree
(H
));
1811 -- Construct "for L_J in Index_Base range L .. H"
1813 L_Iteration_Scheme
:=
1814 Make_Iteration_Scheme
1816 Loop_Parameter_Specification
=>
1817 Make_Loop_Parameter_Specification
1819 Defining_Identifier
=> L_J
,
1820 Discrete_Subtype_Definition
=> L_Range
));
1822 -- Construct the statements to execute in the loop body
1825 Gen_Assign
(New_Occurrence_Of
(L_J
, Loc
), Expr
, In_Loop
=> True);
1827 -- Construct the final loop
1830 Make_Implicit_Loop_Statement
1832 Identifier
=> Empty
,
1833 Iteration_Scheme
=> L_Iteration_Scheme
,
1834 Statements
=> L_Body
));
1836 -- A small optimization: if the aggregate is initialized with a box
1837 -- and the component type has no initialization procedure, remove the
1838 -- useless empty loop.
1840 if Nkind
(First
(S
)) = N_Loop_Statement
1841 and then Is_Empty_List
(Statements
(First
(S
)))
1843 return New_List
(Make_Null_Statement
(Loc
));
1853 -- The code built is
1855 -- W_J : Index_Base := L;
1856 -- while W_J < H loop
1857 -- W_J := Index_Base'Succ (W);
1861 function Gen_While
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1865 -- W_J : Base_Type := L;
1867 W_Iteration_Scheme
: Node_Id
;
1870 W_Index_Succ
: Node_Id
;
1871 -- Index_Base'Succ (J)
1873 W_Increment
: Node_Id
;
1874 -- W_J := Index_Base'Succ (W)
1876 W_Body
: constant List_Id
:= New_List
;
1877 -- The statements to execute in the loop
1879 S
: constant List_Id
:= New_List
;
1880 -- list of statement
1883 -- If loop bounds define an empty range or are equal return null
1885 if Empty_Range
(L
, H
) or else Equal
(L
, H
) then
1886 Append_To
(S
, Make_Null_Statement
(Loc
));
1890 -- Build the decl of W_J
1892 W_J
:= Make_Temporary
(Loc
, 'J', L
);
1894 Make_Object_Declaration
1896 Defining_Identifier
=> W_J
,
1897 Object_Definition
=> Index_Base_Name
,
1900 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1901 -- that in this particular case L is a fresh Expr generated by
1902 -- Add which we are the only ones to use.
1904 Append_To
(S
, W_Decl
);
1906 -- Construct " while W_J < H"
1908 W_Iteration_Scheme
:=
1909 Make_Iteration_Scheme
1911 Condition
=> Make_Op_Lt
1913 Left_Opnd
=> New_Occurrence_Of
(W_J
, Loc
),
1914 Right_Opnd
=> New_Copy_Tree
(H
)));
1916 -- Construct the statements to execute in the loop body
1919 Make_Attribute_Reference
1921 Prefix
=> Index_Base_Name
,
1922 Attribute_Name
=> Name_Succ
,
1923 Expressions
=> New_List
(New_Occurrence_Of
(W_J
, Loc
)));
1926 Make_OK_Assignment_Statement
1928 Name
=> New_Occurrence_Of
(W_J
, Loc
),
1929 Expression
=> W_Index_Succ
);
1931 Append_To
(W_Body
, W_Increment
);
1933 Append_List_To
(W_Body
,
1934 Gen_Assign
(New_Occurrence_Of
(W_J
, Loc
), Expr
, In_Loop
=> True));
1936 -- Construct the final loop
1939 Make_Implicit_Loop_Statement
1941 Identifier
=> Empty
,
1942 Iteration_Scheme
=> W_Iteration_Scheme
,
1943 Statements
=> W_Body
));
1948 --------------------
1949 -- Get_Assoc_Expr --
1950 --------------------
1952 function Get_Assoc_Expr
(Assoc
: Node_Id
) return Node_Id
is
1953 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
1956 if Box_Present
(Assoc
) then
1957 if Is_Scalar_Type
(Ctype
) then
1958 if Present
(Default_Aspect_Component_Value
(Typ
)) then
1959 return Default_Aspect_Component_Value
(Typ
);
1960 elsif Present
(Default_Aspect_Value
(Ctype
)) then
1961 return Default_Aspect_Value
(Ctype
);
1971 return Expression
(Assoc
);
1975 ---------------------
1976 -- Index_Base_Name --
1977 ---------------------
1979 function Index_Base_Name
return Node_Id
is
1981 return New_Occurrence_Of
(Index_Base
, Sloc
(N
));
1982 end Index_Base_Name
;
1984 ------------------------------------
1985 -- Local_Compile_Time_Known_Value --
1986 ------------------------------------
1988 function Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean is
1990 return Compile_Time_Known_Value
(E
)
1992 (Nkind
(E
) = N_Attribute_Reference
1993 and then Attribute_Name
(E
) = Name_Val
1994 and then Compile_Time_Known_Value
(First
(Expressions
(E
))));
1995 end Local_Compile_Time_Known_Value
;
1997 ----------------------
1998 -- Local_Expr_Value --
1999 ----------------------
2001 function Local_Expr_Value
(E
: Node_Id
) return Uint
is
2003 if Compile_Time_Known_Value
(E
) then
2004 return Expr_Value
(E
);
2006 return Expr_Value
(First
(Expressions
(E
)));
2008 end Local_Expr_Value
;
2012 New_Code
: constant List_Id
:= New_List
;
2014 Aggr_L
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(N
));
2015 Aggr_H
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(N
));
2016 -- The aggregate bounds of this specific subaggregate. Note that if the
2017 -- code generated by Build_Array_Aggr_Code is executed then these bounds
2018 -- are OK. Otherwise a Constraint_Error would have been raised.
2020 Aggr_Low
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_L
);
2021 Aggr_High
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_H
);
2022 -- After Duplicate_Subexpr these are side-effect free
2031 Nb_Choices
: Nat
:= 0;
2032 Table
: Case_Table_Type
(1 .. Number_Of_Choices
(N
));
2033 -- Used to sort all the different choice values
2036 -- Number of elements in the positional aggregate
2038 Others_Assoc
: Node_Id
:= Empty
;
2040 -- Start of processing for Build_Array_Aggr_Code
2043 -- First before we start, a special case. if we have a bit packed
2044 -- array represented as a modular type, then clear the value to
2045 -- zero first, to ensure that unused bits are properly cleared.
2050 and then Is_Bit_Packed_Array
(Typ
)
2051 and then Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
))
2053 Append_To
(New_Code
,
2054 Make_Assignment_Statement
(Loc
,
2055 Name
=> New_Copy_Tree
(Into
),
2057 Unchecked_Convert_To
(Typ
,
2058 Make_Integer_Literal
(Loc
, Uint_0
))));
2061 -- If the component type contains tasks, we need to build a Master
2062 -- entity in the current scope, because it will be needed if build-
2063 -- in-place functions are called in the expanded code.
2065 if Nkind
(Parent
(N
)) = N_Object_Declaration
and then Has_Task
(Typ
) then
2066 Build_Master_Entity
(Defining_Identifier
(Parent
(N
)));
2069 -- STEP 1: Process component associations
2071 -- For those associations that may generate a loop, initialize
2072 -- Loop_Actions to collect inserted actions that may be crated.
2074 -- Skip this if no component associations
2076 if No
(Expressions
(N
)) then
2078 -- STEP 1 (a): Sort the discrete choices
2080 Assoc
:= First
(Component_Associations
(N
));
2081 while Present
(Assoc
) loop
2082 Choice
:= First
(Choice_List
(Assoc
));
2083 while Present
(Choice
) loop
2084 if Nkind
(Choice
) = N_Others_Choice
then
2085 Set_Loop_Actions
(Assoc
, New_List
);
2086 Others_Assoc
:= Assoc
;
2090 Get_Index_Bounds
(Choice
, Low
, High
);
2093 Set_Loop_Actions
(Assoc
, New_List
);
2096 Nb_Choices
:= Nb_Choices
+ 1;
2098 Table
(Nb_Choices
) :=
2101 Choice_Node
=> Get_Assoc_Expr
(Assoc
));
2109 -- If there is more than one set of choices these must be static
2110 -- and we can therefore sort them. Remember that Nb_Choices does not
2111 -- account for an others choice.
2113 if Nb_Choices
> 1 then
2114 Sort_Case_Table
(Table
);
2117 -- STEP 1 (b): take care of the whole set of discrete choices
2119 for J
in 1 .. Nb_Choices
loop
2120 Low
:= Table
(J
).Choice_Lo
;
2121 High
:= Table
(J
).Choice_Hi
;
2122 Expr
:= Table
(J
).Choice_Node
;
2123 Append_List
(Gen_Loop
(Low
, High
, Expr
), To
=> New_Code
);
2126 -- STEP 1 (c): generate the remaining loops to cover others choice
2127 -- We don't need to generate loops over empty gaps, but if there is
2128 -- a single empty range we must analyze the expression for semantics
2130 if Present
(Others_Assoc
) then
2132 First
: Boolean := True;
2135 for J
in 0 .. Nb_Choices
loop
2139 Low
:= Add
(1, To
=> Table
(J
).Choice_Hi
);
2142 if J
= Nb_Choices
then
2145 High
:= Add
(-1, To
=> Table
(J
+ 1).Choice_Lo
);
2148 -- If this is an expansion within an init proc, make
2149 -- sure that discriminant references are replaced by
2150 -- the corresponding discriminal.
2152 if Inside_Init_Proc
then
2153 if Is_Entity_Name
(Low
)
2154 and then Ekind
(Entity
(Low
)) = E_Discriminant
2156 Set_Entity
(Low
, Discriminal
(Entity
(Low
)));
2159 if Is_Entity_Name
(High
)
2160 and then Ekind
(Entity
(High
)) = E_Discriminant
2162 Set_Entity
(High
, Discriminal
(Entity
(High
)));
2167 or else not Empty_Range
(Low
, High
)
2171 (Gen_Loop
(Low
, High
,
2172 Get_Assoc_Expr
(Others_Assoc
)), To
=> New_Code
);
2178 -- STEP 2: Process positional components
2181 -- STEP 2 (a): Generate the assignments for each positional element
2182 -- Note that here we have to use Aggr_L rather than Aggr_Low because
2183 -- Aggr_L is analyzed and Add wants an analyzed expression.
2185 Expr
:= First
(Expressions
(N
));
2187 while Present
(Expr
) loop
2188 Nb_Elements
:= Nb_Elements
+ 1;
2189 Append_List
(Gen_Assign
(Add
(Nb_Elements
, To
=> Aggr_L
), Expr
),
2194 -- STEP 2 (b): Generate final loop if an others choice is present
2195 -- Here Nb_Elements gives the offset of the last positional element.
2197 if Present
(Component_Associations
(N
)) then
2198 Assoc
:= Last
(Component_Associations
(N
));
2200 -- Ada 2005 (AI-287)
2202 Append_List
(Gen_While
(Add
(Nb_Elements
, To
=> Aggr_L
),
2204 Get_Assoc_Expr
(Assoc
)), -- AI-287
2210 end Build_Array_Aggr_Code
;
2212 ----------------------------
2213 -- Build_Record_Aggr_Code --
2214 ----------------------------
2216 function Build_Record_Aggr_Code
2219 Lhs
: Node_Id
) return List_Id
2221 Loc
: constant Source_Ptr
:= Sloc
(N
);
2222 L
: constant List_Id
:= New_List
;
2223 N_Typ
: constant Entity_Id
:= Etype
(N
);
2229 Comp_Type
: Entity_Id
;
2230 Selector
: Entity_Id
;
2231 Comp_Expr
: Node_Id
;
2234 -- If this is an internal aggregate, the External_Final_List is an
2235 -- expression for the controller record of the enclosing type.
2237 -- If the current aggregate has several controlled components, this
2238 -- expression will appear in several calls to attach to the finali-
2239 -- zation list, and it must not be shared.
2241 Ancestor_Is_Expression
: Boolean := False;
2242 Ancestor_Is_Subtype_Mark
: Boolean := False;
2244 Init_Typ
: Entity_Id
:= Empty
;
2246 Finalization_Done
: Boolean := False;
2247 -- True if Generate_Finalization_Actions has already been called; calls
2248 -- after the first do nothing.
2250 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
;
2251 -- Returns the value that the given discriminant of an ancestor type
2252 -- should receive (in the absence of a conflict with the value provided
2253 -- by an ancestor part of an extension aggregate).
2255 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
);
2256 -- Check that each of the discriminant values defined by the ancestor
2257 -- part of an extension aggregate match the corresponding values
2258 -- provided by either an association of the aggregate or by the
2259 -- constraint imposed by a parent type (RM95-4.3.2(8)).
2261 function Compatible_Int_Bounds
2262 (Agg_Bounds
: Node_Id
;
2263 Typ_Bounds
: Node_Id
) return Boolean;
2264 -- Return true if Agg_Bounds are equal or within Typ_Bounds. It is
2265 -- assumed that both bounds are integer ranges.
2267 procedure Generate_Finalization_Actions
;
2268 -- Deal with the various controlled type data structure initializations
2269 -- (but only if it hasn't been done already).
2271 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
;
2272 -- Returns the first discriminant association in the constraint
2273 -- associated with T, if any, otherwise returns Empty.
2275 function Get_Explicit_Discriminant_Value
(D
: Entity_Id
) return Node_Id
;
2276 -- If the ancestor part is an unconstrained type and further ancestors
2277 -- do not provide discriminants for it, check aggregate components for
2278 -- values of the discriminants.
2280 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
);
2281 -- If Typ is derived, and constrains discriminants of the parent type,
2282 -- these discriminants are not components of the aggregate, and must be
2283 -- initialized. The assignments are appended to List. The same is done
2284 -- if Typ derives fron an already constrained subtype of a discriminated
2287 procedure Init_Stored_Discriminants
;
2288 -- If the type is derived and has inherited discriminants, generate
2289 -- explicit assignments for each, using the store constraint of the
2290 -- type. Note that both visible and stored discriminants must be
2291 -- initialized in case the derived type has some renamed and some
2292 -- constrained discriminants.
2294 procedure Init_Visible_Discriminants
;
2295 -- If type has discriminants, retrieve their values from aggregate,
2296 -- and generate explicit assignments for each. This does not include
2297 -- discriminants inherited from ancestor, which are handled above.
2298 -- The type of the aggregate is a subtype created ealier using the
2299 -- given values of the discriminant components of the aggregate.
2301 procedure Initialize_Ctrl_Record_Component
2302 (Rec_Comp
: Node_Id
;
2303 Comp_Typ
: Entity_Id
;
2304 Init_Expr
: Node_Id
;
2306 -- Perform the initialization of controlled record component Rec_Comp.
2307 -- Comp_Typ is the component type. Init_Expr is the initialization
2308 -- expression for the record component. Hook-related declarations are
2309 -- inserted prior to aggregate N using Insert_Action. All remaining
2310 -- generated code is added to list Stmts.
2312 procedure Initialize_Record_Component
2313 (Rec_Comp
: Node_Id
;
2314 Comp_Typ
: Entity_Id
;
2315 Init_Expr
: Node_Id
;
2317 -- Perform the initialization of record component Rec_Comp. Comp_Typ
2318 -- is the component type. Init_Expr is the initialization expression
2319 -- of the record component. All generated code is added to list Stmts.
2321 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean;
2322 -- Check whether Bounds is a range node and its lower and higher bounds
2323 -- are integers literals.
2325 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
;
2326 -- If the aggregate contains a self-reference, traverse each expression
2327 -- to replace a possible self-reference with a reference to the proper
2328 -- component of the target of the assignment.
2330 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
;
2331 -- If default expression of a component mentions a discriminant of the
2332 -- type, it must be rewritten as the discriminant of the target object.
2334 ---------------------------------
2335 -- Ancestor_Discriminant_Value --
2336 ---------------------------------
2338 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
is
2340 Assoc_Elmt
: Elmt_Id
;
2341 Aggr_Comp
: Entity_Id
;
2342 Corresp_Disc
: Entity_Id
;
2343 Current_Typ
: Entity_Id
:= Base_Type
(Typ
);
2344 Parent_Typ
: Entity_Id
;
2345 Parent_Disc
: Entity_Id
;
2346 Save_Assoc
: Node_Id
:= Empty
;
2349 -- First check any discriminant associations to see if any of them
2350 -- provide a value for the discriminant.
2352 if Present
(Discriminant_Specifications
(Parent
(Current_Typ
))) then
2353 Assoc
:= First
(Component_Associations
(N
));
2354 while Present
(Assoc
) loop
2355 Aggr_Comp
:= Entity
(First
(Choices
(Assoc
)));
2357 if Ekind
(Aggr_Comp
) = E_Discriminant
then
2358 Save_Assoc
:= Expression
(Assoc
);
2360 Corresp_Disc
:= Corresponding_Discriminant
(Aggr_Comp
);
2361 while Present
(Corresp_Disc
) loop
2363 -- If found a corresponding discriminant then return the
2364 -- value given in the aggregate. (Note: this is not
2365 -- correct in the presence of side effects. ???)
2367 if Disc
= Corresp_Disc
then
2368 return Duplicate_Subexpr
(Expression
(Assoc
));
2371 Corresp_Disc
:= Corresponding_Discriminant
(Corresp_Disc
);
2379 -- No match found in aggregate, so chain up parent types to find
2380 -- a constraint that defines the value of the discriminant.
2382 Parent_Typ
:= Etype
(Current_Typ
);
2383 while Current_Typ
/= Parent_Typ
loop
2384 if Has_Discriminants
(Parent_Typ
)
2385 and then not Has_Unknown_Discriminants
(Parent_Typ
)
2387 Parent_Disc
:= First_Discriminant
(Parent_Typ
);
2389 -- We either get the association from the subtype indication
2390 -- of the type definition itself, or from the discriminant
2391 -- constraint associated with the type entity (which is
2392 -- preferable, but it's not always present ???)
2394 if Is_Empty_Elmt_List
(Discriminant_Constraint
(Current_Typ
))
2396 Assoc
:= Get_Constraint_Association
(Current_Typ
);
2397 Assoc_Elmt
:= No_Elmt
;
2400 First_Elmt
(Discriminant_Constraint
(Current_Typ
));
2401 Assoc
:= Node
(Assoc_Elmt
);
2404 -- Traverse the discriminants of the parent type looking
2405 -- for one that corresponds.
2407 while Present
(Parent_Disc
) and then Present
(Assoc
) loop
2408 Corresp_Disc
:= Parent_Disc
;
2409 while Present
(Corresp_Disc
)
2410 and then Disc
/= Corresp_Disc
2412 Corresp_Disc
:= Corresponding_Discriminant
(Corresp_Disc
);
2415 if Disc
= Corresp_Disc
then
2416 if Nkind
(Assoc
) = N_Discriminant_Association
then
2417 Assoc
:= Expression
(Assoc
);
2420 -- If the located association directly denotes
2421 -- a discriminant, then use the value of a saved
2422 -- association of the aggregate. This is an approach
2423 -- used to handle certain cases involving multiple
2424 -- discriminants mapped to a single discriminant of
2425 -- a descendant. It's not clear how to locate the
2426 -- appropriate discriminant value for such cases. ???
2428 if Is_Entity_Name
(Assoc
)
2429 and then Ekind
(Entity
(Assoc
)) = E_Discriminant
2431 Assoc
:= Save_Assoc
;
2434 return Duplicate_Subexpr
(Assoc
);
2437 Next_Discriminant
(Parent_Disc
);
2439 if No
(Assoc_Elmt
) then
2443 Next_Elmt
(Assoc_Elmt
);
2445 if Present
(Assoc_Elmt
) then
2446 Assoc
:= Node
(Assoc_Elmt
);
2454 Current_Typ
:= Parent_Typ
;
2455 Parent_Typ
:= Etype
(Current_Typ
);
2458 -- In some cases there's no ancestor value to locate (such as
2459 -- when an ancestor part given by an expression defines the
2460 -- discriminant value).
2463 end Ancestor_Discriminant_Value
;
2465 ----------------------------------
2466 -- Check_Ancestor_Discriminants --
2467 ----------------------------------
2469 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
) is
2471 Disc_Value
: Node_Id
;
2475 Discr
:= First_Discriminant
(Base_Type
(Anc_Typ
));
2476 while Present
(Discr
) loop
2477 Disc_Value
:= Ancestor_Discriminant_Value
(Discr
);
2479 if Present
(Disc_Value
) then
2480 Cond
:= Make_Op_Ne
(Loc
,
2482 Make_Selected_Component
(Loc
,
2483 Prefix
=> New_Copy_Tree
(Target
),
2484 Selector_Name
=> New_Occurrence_Of
(Discr
, Loc
)),
2485 Right_Opnd
=> Disc_Value
);
2488 Make_Raise_Constraint_Error
(Loc
,
2490 Reason
=> CE_Discriminant_Check_Failed
));
2493 Next_Discriminant
(Discr
);
2495 end Check_Ancestor_Discriminants
;
2497 ---------------------------
2498 -- Compatible_Int_Bounds --
2499 ---------------------------
2501 function Compatible_Int_Bounds
2502 (Agg_Bounds
: Node_Id
;
2503 Typ_Bounds
: Node_Id
) return Boolean
2505 Agg_Lo
: constant Uint
:= Intval
(Low_Bound
(Agg_Bounds
));
2506 Agg_Hi
: constant Uint
:= Intval
(High_Bound
(Agg_Bounds
));
2507 Typ_Lo
: constant Uint
:= Intval
(Low_Bound
(Typ_Bounds
));
2508 Typ_Hi
: constant Uint
:= Intval
(High_Bound
(Typ_Bounds
));
2510 return Typ_Lo
<= Agg_Lo
and then Agg_Hi
<= Typ_Hi
;
2511 end Compatible_Int_Bounds
;
2513 -----------------------------------
2514 -- Generate_Finalization_Actions --
2515 -----------------------------------
2517 procedure Generate_Finalization_Actions
is
2519 -- Do the work only the first time this is called
2521 if Finalization_Done
then
2525 Finalization_Done
:= True;
2527 -- Determine the external finalization list. It is either the
2528 -- finalization list of the outer scope or the one coming from an
2529 -- outer aggregate. When the target is not a temporary, the proper
2530 -- scope is the scope of the target rather than the potentially
2531 -- transient current scope.
2533 if Is_Controlled
(Typ
) and then Ancestor_Is_Subtype_Mark
then
2534 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2535 Set_Assignment_OK
(Ref
);
2538 Make_Procedure_Call_Statement
(Loc
,
2541 (Find_Prim_Op
(Init_Typ
, Name_Initialize
), Loc
),
2542 Parameter_Associations
=> New_List
(New_Copy_Tree
(Ref
))));
2544 end Generate_Finalization_Actions
;
2546 --------------------------------
2547 -- Get_Constraint_Association --
2548 --------------------------------
2550 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
is
2557 -- If type is private, get constraint from full view. This was
2558 -- previously done in an instance context, but is needed whenever
2559 -- the ancestor part has a discriminant, possibly inherited through
2560 -- multiple derivations.
2562 if Is_Private_Type
(Typ
) and then Present
(Full_View
(Typ
)) then
2563 Typ
:= Full_View
(Typ
);
2566 Indic
:= Subtype_Indication
(Type_Definition
(Parent
(Typ
)));
2568 -- Verify that the subtype indication carries a constraint
2570 if Nkind
(Indic
) = N_Subtype_Indication
2571 and then Present
(Constraint
(Indic
))
2573 return First
(Constraints
(Constraint
(Indic
)));
2577 end Get_Constraint_Association
;
2579 -------------------------------------
2580 -- Get_Explicit_Discriminant_Value --
2581 -------------------------------------
2583 function Get_Explicit_Discriminant_Value
2584 (D
: Entity_Id
) return Node_Id
2591 -- The aggregate has been normalized and all associations have a
2594 Assoc
:= First
(Component_Associations
(N
));
2595 while Present
(Assoc
) loop
2596 Choice
:= First
(Choices
(Assoc
));
2598 if Chars
(Choice
) = Chars
(D
) then
2599 Val
:= Expression
(Assoc
);
2608 end Get_Explicit_Discriminant_Value
;
2610 -------------------------------
2611 -- Init_Hidden_Discriminants --
2612 -------------------------------
2614 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
) is
2615 function Is_Completely_Hidden_Discriminant
2616 (Discr
: Entity_Id
) return Boolean;
2617 -- Determine whether Discr is a completely hidden discriminant of
2620 ---------------------------------------
2621 -- Is_Completely_Hidden_Discriminant --
2622 ---------------------------------------
2624 function Is_Completely_Hidden_Discriminant
2625 (Discr
: Entity_Id
) return Boolean
2630 -- Use First/Next_Entity as First/Next_Discriminant do not yield
2631 -- completely hidden discriminants.
2633 Item
:= First_Entity
(Typ
);
2634 while Present
(Item
) loop
2635 if Ekind
(Item
) = E_Discriminant
2636 and then Is_Completely_Hidden
(Item
)
2637 and then Chars
(Original_Record_Component
(Item
)) =
2647 end Is_Completely_Hidden_Discriminant
;
2651 Base_Typ
: Entity_Id
;
2653 Discr_Constr
: Elmt_Id
;
2654 Discr_Init
: Node_Id
;
2655 Discr_Val
: Node_Id
;
2656 In_Aggr_Type
: Boolean;
2657 Par_Typ
: Entity_Id
;
2659 -- Start of processing for Init_Hidden_Discriminants
2662 -- The constraints on the hidden discriminants, if present, are kept
2663 -- in the Stored_Constraint list of the type itself, or in that of
2664 -- the base type. If not in the constraints of the aggregate itself,
2665 -- we examine ancestors to find discriminants that are not renamed
2666 -- by other discriminants but constrained explicitly.
2668 In_Aggr_Type
:= True;
2670 Base_Typ
:= Base_Type
(Typ
);
2671 while Is_Derived_Type
(Base_Typ
)
2673 (Present
(Stored_Constraint
(Base_Typ
))
2675 (In_Aggr_Type
and then Present
(Stored_Constraint
(Typ
))))
2677 Par_Typ
:= Etype
(Base_Typ
);
2679 if not Has_Discriminants
(Par_Typ
) then
2683 Discr
:= First_Discriminant
(Par_Typ
);
2685 -- We know that one of the stored-constraint lists is present
2687 if Present
(Stored_Constraint
(Base_Typ
)) then
2688 Discr_Constr
:= First_Elmt
(Stored_Constraint
(Base_Typ
));
2690 -- For private extension, stored constraint may be on full view
2692 elsif Is_Private_Type
(Base_Typ
)
2693 and then Present
(Full_View
(Base_Typ
))
2694 and then Present
(Stored_Constraint
(Full_View
(Base_Typ
)))
2697 First_Elmt
(Stored_Constraint
(Full_View
(Base_Typ
)));
2700 Discr_Constr
:= First_Elmt
(Stored_Constraint
(Typ
));
2703 while Present
(Discr
) and then Present
(Discr_Constr
) loop
2704 Discr_Val
:= Node
(Discr_Constr
);
2706 -- The parent discriminant is renamed in the derived type,
2707 -- nothing to initialize.
2709 -- type Deriv_Typ (Discr : ...)
2710 -- is new Parent_Typ (Discr => Discr);
2712 if Is_Entity_Name
(Discr_Val
)
2713 and then Ekind
(Entity
(Discr_Val
)) = E_Discriminant
2717 -- When the parent discriminant is constrained at the type
2718 -- extension level, it does not appear in the derived type.
2720 -- type Deriv_Typ (Discr : ...)
2721 -- is new Parent_Typ (Discr => Discr,
2722 -- Hidden_Discr => Expression);
2724 elsif Is_Completely_Hidden_Discriminant
(Discr
) then
2727 -- Otherwise initialize the discriminant
2731 Make_OK_Assignment_Statement
(Loc
,
2733 Make_Selected_Component
(Loc
,
2734 Prefix
=> New_Copy_Tree
(Target
),
2735 Selector_Name
=> New_Occurrence_Of
(Discr
, Loc
)),
2736 Expression
=> New_Copy_Tree
(Discr_Val
));
2738 Append_To
(List
, Discr_Init
);
2741 Next_Elmt
(Discr_Constr
);
2742 Next_Discriminant
(Discr
);
2745 In_Aggr_Type
:= False;
2746 Base_Typ
:= Base_Type
(Par_Typ
);
2748 end Init_Hidden_Discriminants
;
2750 --------------------------------
2751 -- Init_Visible_Discriminants --
2752 --------------------------------
2754 procedure Init_Visible_Discriminants
is
2755 Discriminant
: Entity_Id
;
2756 Discriminant_Value
: Node_Id
;
2759 Discriminant
:= First_Discriminant
(Typ
);
2760 while Present
(Discriminant
) loop
2762 Make_Selected_Component
(Loc
,
2763 Prefix
=> New_Copy_Tree
(Target
),
2764 Selector_Name
=> New_Occurrence_Of
(Discriminant
, Loc
));
2766 Discriminant_Value
:=
2767 Get_Discriminant_Value
2768 (Discriminant
, Typ
, Discriminant_Constraint
(N_Typ
));
2771 Make_OK_Assignment_Statement
(Loc
,
2773 Expression
=> New_Copy_Tree
(Discriminant_Value
));
2775 Append_To
(L
, Instr
);
2777 Next_Discriminant
(Discriminant
);
2779 end Init_Visible_Discriminants
;
2781 -------------------------------
2782 -- Init_Stored_Discriminants --
2783 -------------------------------
2785 procedure Init_Stored_Discriminants
is
2786 Discriminant
: Entity_Id
;
2787 Discriminant_Value
: Node_Id
;
2790 Discriminant
:= First_Stored_Discriminant
(Typ
);
2791 while Present
(Discriminant
) loop
2793 Make_Selected_Component
(Loc
,
2794 Prefix
=> New_Copy_Tree
(Target
),
2795 Selector_Name
=> New_Occurrence_Of
(Discriminant
, Loc
));
2797 Discriminant_Value
:=
2798 Get_Discriminant_Value
2799 (Discriminant
, N_Typ
, Discriminant_Constraint
(N_Typ
));
2802 Make_OK_Assignment_Statement
(Loc
,
2804 Expression
=> New_Copy_Tree
(Discriminant_Value
));
2806 Append_To
(L
, Instr
);
2808 Next_Stored_Discriminant
(Discriminant
);
2810 end Init_Stored_Discriminants
;
2812 --------------------------------------
2813 -- Initialize_Ctrl_Record_Component --
2814 --------------------------------------
2816 procedure Initialize_Ctrl_Record_Component
2817 (Rec_Comp
: Node_Id
;
2818 Comp_Typ
: Entity_Id
;
2819 Init_Expr
: Node_Id
;
2823 Hook_Clear
: Node_Id
;
2825 In_Place_Expansion
: Boolean;
2826 -- Flag set when a nonlimited controlled function call requires
2827 -- in-place expansion.
2830 -- Perform a preliminary analysis and resolution to determine what
2831 -- the initialization expression denotes. Unanalyzed function calls
2832 -- may appear as identifiers or indexed components.
2834 if Nkind_In
(Init_Expr
, N_Function_Call
,
2836 N_Indexed_Component
)
2837 and then not Analyzed
(Init_Expr
)
2839 Preanalyze_And_Resolve
(Init_Expr
, Comp_Typ
);
2842 In_Place_Expansion
:=
2843 Nkind
(Init_Expr
) = N_Function_Call
2844 and then not Is_Build_In_Place_Result_Type
(Comp_Typ
);
2846 -- The initialization expression is a controlled function call.
2847 -- Perform in-place removal of side effects to avoid creating a
2850 -- This in-place expansion is not performed for limited transient
2851 -- objects because the initialization is already done in place.
2853 if In_Place_Expansion
then
2855 -- Suppress the removal of side effects by general analysis
2856 -- because this behavior is emulated here. This avoids the
2857 -- generation of a transient scope, which leads to out-of-order
2858 -- adjustment and finalization.
2860 Set_No_Side_Effect_Removal
(Init_Expr
);
2862 -- Install all hook-related declarations and prepare the clean up
2863 -- statements. The generated code follows the initialization order
2864 -- of individual components and discriminants, rather than being
2865 -- inserted prior to the aggregate. This ensures that a transient
2866 -- component which mentions a discriminant has proper visibility
2867 -- of the discriminant.
2869 Process_Transient_Component
2871 Comp_Typ
=> Comp_Typ
,
2872 Init_Expr
=> Init_Expr
,
2873 Fin_Call
=> Fin_Call
,
2874 Hook_Clear
=> Hook_Clear
,
2878 -- Use the noncontrolled component initialization circuitry to
2879 -- assign the result of the function call to the record component.
2880 -- This also performs tag adjustment and [deep] adjustment of the
2881 -- record component.
2883 Initialize_Record_Component
2884 (Rec_Comp
=> Rec_Comp
,
2885 Comp_Typ
=> Comp_Typ
,
2886 Init_Expr
=> Init_Expr
,
2889 -- At this point the record component is fully initialized. Complete
2890 -- the processing of the controlled record component by finalizing
2891 -- the transient function result.
2893 if In_Place_Expansion
then
2894 Process_Transient_Component_Completion
2897 Fin_Call
=> Fin_Call
,
2898 Hook_Clear
=> Hook_Clear
,
2901 end Initialize_Ctrl_Record_Component
;
2903 ---------------------------------
2904 -- Initialize_Record_Component --
2905 ---------------------------------
2907 procedure Initialize_Record_Component
2908 (Rec_Comp
: Node_Id
;
2909 Comp_Typ
: Entity_Id
;
2910 Init_Expr
: Node_Id
;
2913 Exceptions_OK
: constant Boolean :=
2914 not Restriction_Active
(No_Exception_Propagation
);
2916 Finalization_OK
: constant Boolean := Needs_Finalization
(Comp_Typ
);
2918 Full_Typ
: constant Entity_Id
:= Underlying_Type
(Comp_Typ
);
2920 Blk_Stmts
: List_Id
;
2921 Init_Stmt
: Node_Id
;
2924 -- Protect the initialization statements from aborts. Generate:
2928 if Finalization_OK
and Abort_Allowed
then
2929 if Exceptions_OK
then
2930 Blk_Stmts
:= New_List
;
2935 Append_To
(Blk_Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
2937 -- Otherwise aborts are not allowed. All generated code is added
2938 -- directly to the input list.
2944 -- Initialize the record component. Generate:
2946 -- Rec_Comp := Init_Expr;
2948 -- Note that the initialization expression is NOT replicated because
2949 -- only a single component may be initialized by it.
2952 Make_OK_Assignment_Statement
(Loc
,
2953 Name
=> New_Copy_Tree
(Rec_Comp
),
2954 Expression
=> Init_Expr
);
2955 Set_No_Ctrl_Actions
(Init_Stmt
);
2957 Append_To
(Blk_Stmts
, Init_Stmt
);
2959 -- Adjust the tag due to a possible view conversion. Generate:
2961 -- Rec_Comp._tag := Full_TypeP;
2963 if Tagged_Type_Expansion
and then Is_Tagged_Type
(Comp_Typ
) then
2964 Append_To
(Blk_Stmts
,
2965 Make_OK_Assignment_Statement
(Loc
,
2967 Make_Selected_Component
(Loc
,
2968 Prefix
=> New_Copy_Tree
(Rec_Comp
),
2971 (First_Tag_Component
(Full_Typ
), Loc
)),
2974 Unchecked_Convert_To
(RTE
(RE_Tag
),
2976 (Node
(First_Elmt
(Access_Disp_Table
(Full_Typ
))),
2980 -- Adjust the component. Generate:
2982 -- [Deep_]Adjust (Rec_Comp);
2985 and then not Is_Limited_Type
(Comp_Typ
)
2986 and then not Is_Build_In_Place_Function_Call
(Init_Expr
)
2990 (Obj_Ref
=> New_Copy_Tree
(Rec_Comp
),
2993 -- Guard against a missing [Deep_]Adjust when the component type
2994 -- was not properly frozen.
2996 if Present
(Adj_Call
) then
2997 Append_To
(Blk_Stmts
, Adj_Call
);
3001 -- Complete the protection of the initialization statements
3003 if Finalization_OK
and Abort_Allowed
then
3005 -- Wrap the initialization statements in a block to catch a
3006 -- potential exception. Generate:
3010 -- Rec_Comp := Init_Expr;
3011 -- Rec_Comp._tag := Full_TypP;
3012 -- [Deep_]Adjust (Rec_Comp);
3014 -- Abort_Undefer_Direct;
3017 if Exceptions_OK
then
3019 Build_Abort_Undefer_Block
(Loc
,
3023 -- Otherwise exceptions are not propagated. Generate:
3026 -- Rec_Comp := Init_Expr;
3027 -- Rec_Comp._tag := Full_TypP;
3028 -- [Deep_]Adjust (Rec_Comp);
3032 Append_To
(Blk_Stmts
,
3033 Build_Runtime_Call
(Loc
, RE_Abort_Undefer
));
3036 end Initialize_Record_Component
;
3038 -------------------------
3039 -- Is_Int_Range_Bounds --
3040 -------------------------
3042 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean is
3044 return Nkind
(Bounds
) = N_Range
3045 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
3046 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
;
3047 end Is_Int_Range_Bounds
;
3053 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
is
3055 -- Note regarding the Root_Type test below: Aggregate components for
3056 -- self-referential types include attribute references to the current
3057 -- instance, of the form: Typ'access, etc.. These references are
3058 -- rewritten as references to the target of the aggregate: the
3059 -- left-hand side of an assignment, the entity in a declaration,
3060 -- or a temporary. Without this test, we would improperly extended
3061 -- this rewriting to attribute references whose prefix was not the
3062 -- type of the aggregate.
3064 if Nkind
(Expr
) = N_Attribute_Reference
3065 and then Is_Entity_Name
(Prefix
(Expr
))
3066 and then Is_Type
(Entity
(Prefix
(Expr
)))
3067 and then Root_Type
(Etype
(N
)) = Root_Type
(Entity
(Prefix
(Expr
)))
3069 if Is_Entity_Name
(Lhs
) then
3070 Rewrite
(Prefix
(Expr
), New_Occurrence_Of
(Entity
(Lhs
), Loc
));
3074 Make_Attribute_Reference
(Loc
,
3075 Attribute_Name
=> Name_Unrestricted_Access
,
3076 Prefix
=> New_Copy_Tree
(Lhs
)));
3077 Set_Analyzed
(Parent
(Expr
), False);
3084 --------------------------
3085 -- Rewrite_Discriminant --
3086 --------------------------
3088 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
is
3090 if Is_Entity_Name
(Expr
)
3091 and then Present
(Entity
(Expr
))
3092 and then Ekind
(Entity
(Expr
)) = E_In_Parameter
3093 and then Present
(Discriminal_Link
(Entity
(Expr
)))
3094 and then Scope
(Discriminal_Link
(Entity
(Expr
))) =
3095 Base_Type
(Etype
(N
))
3098 Make_Selected_Component
(Loc
,
3099 Prefix
=> New_Copy_Tree
(Lhs
),
3100 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Expr
))));
3104 end Rewrite_Discriminant
;
3106 procedure Replace_Discriminants
is
3107 new Traverse_Proc
(Rewrite_Discriminant
);
3109 procedure Replace_Self_Reference
is
3110 new Traverse_Proc
(Replace_Type
);
3112 -- Start of processing for Build_Record_Aggr_Code
3115 if Has_Self_Reference
(N
) then
3116 Replace_Self_Reference
(N
);
3119 -- If the target of the aggregate is class-wide, we must convert it
3120 -- to the actual type of the aggregate, so that the proper components
3121 -- are visible. We know already that the types are compatible.
3123 if Present
(Etype
(Lhs
))
3124 and then Is_Class_Wide_Type
(Etype
(Lhs
))
3126 Target
:= Unchecked_Convert_To
(Typ
, Lhs
);
3131 -- Deal with the ancestor part of extension aggregates or with the
3132 -- discriminants of the root type.
3134 if Nkind
(N
) = N_Extension_Aggregate
then
3136 Ancestor
: constant Node_Id
:= Ancestor_Part
(N
);
3141 -- If the ancestor part is a subtype mark "T", we generate
3143 -- init-proc (T (tmp)); if T is constrained and
3144 -- init-proc (S (tmp)); where S applies an appropriate
3145 -- constraint if T is unconstrained
3147 if Is_Entity_Name
(Ancestor
)
3148 and then Is_Type
(Entity
(Ancestor
))
3150 Ancestor_Is_Subtype_Mark
:= True;
3152 if Is_Constrained
(Entity
(Ancestor
)) then
3153 Init_Typ
:= Entity
(Ancestor
);
3155 -- For an ancestor part given by an unconstrained type mark,
3156 -- create a subtype constrained by appropriate corresponding
3157 -- discriminant values coming from either associations of the
3158 -- aggregate or a constraint on a parent type. The subtype will
3159 -- be used to generate the correct default value for the
3162 elsif Has_Discriminants
(Entity
(Ancestor
)) then
3164 Anc_Typ
: constant Entity_Id
:= Entity
(Ancestor
);
3165 Anc_Constr
: constant List_Id
:= New_List
;
3166 Discrim
: Entity_Id
;
3167 Disc_Value
: Node_Id
;
3168 New_Indic
: Node_Id
;
3169 Subt_Decl
: Node_Id
;
3172 Discrim
:= First_Discriminant
(Anc_Typ
);
3173 while Present
(Discrim
) loop
3174 Disc_Value
:= Ancestor_Discriminant_Value
(Discrim
);
3176 -- If no usable discriminant in ancestors, check
3177 -- whether aggregate has an explicit value for it.
3179 if No
(Disc_Value
) then
3181 Get_Explicit_Discriminant_Value
(Discrim
);
3184 Append_To
(Anc_Constr
, Disc_Value
);
3185 Next_Discriminant
(Discrim
);
3189 Make_Subtype_Indication
(Loc
,
3190 Subtype_Mark
=> New_Occurrence_Of
(Anc_Typ
, Loc
),
3192 Make_Index_Or_Discriminant_Constraint
(Loc
,
3193 Constraints
=> Anc_Constr
));
3195 Init_Typ
:= Create_Itype
(Ekind
(Anc_Typ
), N
);
3198 Make_Subtype_Declaration
(Loc
,
3199 Defining_Identifier
=> Init_Typ
,
3200 Subtype_Indication
=> New_Indic
);
3202 -- Itypes must be analyzed with checks off Declaration
3203 -- must have a parent for proper handling of subsidiary
3206 Set_Parent
(Subt_Decl
, N
);
3207 Analyze
(Subt_Decl
, Suppress
=> All_Checks
);
3211 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
3212 Set_Assignment_OK
(Ref
);
3214 if not Is_Interface
(Init_Typ
) then
3216 Build_Initialization_Call
(Loc
,
3219 In_Init_Proc
=> Within_Init_Proc
,
3220 With_Default_Init
=> Has_Default_Init_Comps
(N
)
3222 Has_Task
(Base_Type
(Init_Typ
))));
3224 if Is_Constrained
(Entity
(Ancestor
))
3225 and then Has_Discriminants
(Entity
(Ancestor
))
3227 Check_Ancestor_Discriminants
(Entity
(Ancestor
));
3231 -- Handle calls to C++ constructors
3233 elsif Is_CPP_Constructor_Call
(Ancestor
) then
3234 Init_Typ
:= Etype
(Ancestor
);
3235 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
3236 Set_Assignment_OK
(Ref
);
3239 Build_Initialization_Call
(Loc
,
3242 In_Init_Proc
=> Within_Init_Proc
,
3243 With_Default_Init
=> Has_Default_Init_Comps
(N
),
3244 Constructor_Ref
=> Ancestor
));
3246 -- Ada 2005 (AI-287): If the ancestor part is an aggregate of
3247 -- limited type, a recursive call expands the ancestor. Note that
3248 -- in the limited case, the ancestor part must be either a
3249 -- function call (possibly qualified) or aggregate (definitely
3252 elsif Is_Limited_Type
(Etype
(Ancestor
))
3253 and then Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
3254 N_Extension_Aggregate
)
3256 Ancestor_Is_Expression
:= True;
3258 -- Set up finalization data for enclosing record, because
3259 -- controlled subcomponents of the ancestor part will be
3262 Generate_Finalization_Actions
;
3265 Build_Record_Aggr_Code
3266 (N
=> Unqualify
(Ancestor
),
3267 Typ
=> Etype
(Unqualify
(Ancestor
)),
3270 -- If the ancestor part is an expression "E", we generate
3274 -- In Ada 2005, this includes the case of a (possibly qualified)
3275 -- limited function call. The assignment will turn into a
3276 -- build-in-place function call (for further details, see
3277 -- Make_Build_In_Place_Call_In_Assignment).
3280 Ancestor_Is_Expression
:= True;
3281 Init_Typ
:= Etype
(Ancestor
);
3283 -- If the ancestor part is an aggregate, force its full
3284 -- expansion, which was delayed.
3286 if Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
3287 N_Extension_Aggregate
)
3289 Set_Analyzed
(Ancestor
, False);
3290 Set_Analyzed
(Expression
(Ancestor
), False);
3293 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
3294 Set_Assignment_OK
(Ref
);
3296 -- Make the assignment without usual controlled actions, since
3297 -- we only want to Adjust afterwards, but not to Finalize
3298 -- beforehand. Add manual Adjust when necessary.
3300 Assign
:= New_List
(
3301 Make_OK_Assignment_Statement
(Loc
,
3303 Expression
=> Ancestor
));
3304 Set_No_Ctrl_Actions
(First
(Assign
));
3306 -- Assign the tag now to make sure that the dispatching call in
3307 -- the subsequent deep_adjust works properly (unless
3308 -- Tagged_Type_Expansion where tags are implicit).
3310 if Tagged_Type_Expansion
then
3312 Make_OK_Assignment_Statement
(Loc
,
3314 Make_Selected_Component
(Loc
,
3315 Prefix
=> New_Copy_Tree
(Target
),
3318 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
3321 Unchecked_Convert_To
(RTE
(RE_Tag
),
3324 (Access_Disp_Table
(Base_Type
(Typ
)))),
3327 Set_Assignment_OK
(Name
(Instr
));
3328 Append_To
(Assign
, Instr
);
3330 -- Ada 2005 (AI-251): If tagged type has progenitors we must
3331 -- also initialize tags of the secondary dispatch tables.
3333 if Has_Interfaces
(Base_Type
(Typ
)) then
3335 (Typ
=> Base_Type
(Typ
),
3337 Stmts_List
=> Assign
,
3338 Init_Tags_List
=> Assign
);
3342 -- Call Adjust manually
3344 if Needs_Finalization
(Etype
(Ancestor
))
3345 and then not Is_Limited_Type
(Etype
(Ancestor
))
3346 and then not Is_Build_In_Place_Function_Call
(Ancestor
)
3350 (Obj_Ref
=> New_Copy_Tree
(Ref
),
3351 Typ
=> Etype
(Ancestor
));
3353 -- Guard against a missing [Deep_]Adjust when the ancestor
3354 -- type was not properly frozen.
3356 if Present
(Adj_Call
) then
3357 Append_To
(Assign
, Adj_Call
);
3362 Make_Unsuppress_Block
(Loc
, Name_Discriminant_Check
, Assign
));
3364 if Has_Discriminants
(Init_Typ
) then
3365 Check_Ancestor_Discriminants
(Init_Typ
);
3369 pragma Assert
(Nkind
(N
) = N_Extension_Aggregate
);
3371 (not (Ancestor_Is_Expression
and Ancestor_Is_Subtype_Mark
));
3374 -- Generate assignments of hidden discriminants. If the base type is
3375 -- an unchecked union, the discriminants are unknown to the back-end
3376 -- and absent from a value of the type, so assignments for them are
3379 if Has_Discriminants
(Typ
)
3380 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
3382 Init_Hidden_Discriminants
(Typ
, L
);
3385 -- Normal case (not an extension aggregate)
3388 -- Generate the discriminant expressions, component by component.
3389 -- If the base type is an unchecked union, the discriminants are
3390 -- unknown to the back-end and absent from a value of the type, so
3391 -- assignments for them are not emitted.
3393 if Has_Discriminants
(Typ
)
3394 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
3396 Init_Hidden_Discriminants
(Typ
, L
);
3398 -- Generate discriminant init values for the visible discriminants
3400 Init_Visible_Discriminants
;
3402 if Is_Derived_Type
(N_Typ
) then
3403 Init_Stored_Discriminants
;
3408 -- For CPP types we generate an implicit call to the C++ default
3409 -- constructor to ensure the proper initialization of the _Tag
3412 if Is_CPP_Class
(Root_Type
(Typ
)) and then CPP_Num_Prims
(Typ
) > 0 then
3413 Invoke_Constructor
: declare
3414 CPP_Parent
: constant Entity_Id
:= Enclosing_CPP_Parent
(Typ
);
3416 procedure Invoke_IC_Proc
(T
: Entity_Id
);
3417 -- Recursive routine used to climb to parents. Required because
3418 -- parents must be initialized before descendants to ensure
3419 -- propagation of inherited C++ slots.
3421 --------------------
3422 -- Invoke_IC_Proc --
3423 --------------------
3425 procedure Invoke_IC_Proc
(T
: Entity_Id
) is
3427 -- Avoid generating extra calls. Initialization required
3428 -- only for types defined from the level of derivation of
3429 -- type of the constructor and the type of the aggregate.
3431 if T
= CPP_Parent
then
3435 Invoke_IC_Proc
(Etype
(T
));
3437 -- Generate call to the IC routine
3439 if Present
(CPP_Init_Proc
(T
)) then
3441 Make_Procedure_Call_Statement
(Loc
,
3442 Name
=> New_Occurrence_Of
(CPP_Init_Proc
(T
), Loc
)));
3446 -- Start of processing for Invoke_Constructor
3449 -- Implicit invocation of the C++ constructor
3451 if Nkind
(N
) = N_Aggregate
then
3453 Make_Procedure_Call_Statement
(Loc
,
3455 New_Occurrence_Of
(Base_Init_Proc
(CPP_Parent
), Loc
),
3456 Parameter_Associations
=> New_List
(
3457 Unchecked_Convert_To
(CPP_Parent
,
3458 New_Copy_Tree
(Lhs
)))));
3461 Invoke_IC_Proc
(Typ
);
3462 end Invoke_Constructor
;
3465 -- Generate the assignments, component by component
3467 -- tmp.comp1 := Expr1_From_Aggr;
3468 -- tmp.comp2 := Expr2_From_Aggr;
3471 Comp
:= First
(Component_Associations
(N
));
3472 while Present
(Comp
) loop
3473 Selector
:= Entity
(First
(Choices
(Comp
)));
3477 if Is_CPP_Constructor_Call
(Expression
(Comp
)) then
3479 Build_Initialization_Call
(Loc
,
3481 Make_Selected_Component
(Loc
,
3482 Prefix
=> New_Copy_Tree
(Target
),
3483 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
)),
3484 Typ
=> Etype
(Selector
),
3486 With_Default_Init
=> True,
3487 Constructor_Ref
=> Expression
(Comp
)));
3489 -- Ada 2005 (AI-287): For each default-initialized component generate
3490 -- a call to the corresponding IP subprogram if available.
3492 elsif Box_Present
(Comp
)
3493 and then Has_Non_Null_Base_Init_Proc
(Etype
(Selector
))
3495 if Ekind
(Selector
) /= E_Discriminant
then
3496 Generate_Finalization_Actions
;
3499 -- Ada 2005 (AI-287): If the component type has tasks then
3500 -- generate the activation chain and master entities (except
3501 -- in case of an allocator because in that case these entities
3502 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
3505 Ctype
: constant Entity_Id
:= Etype
(Selector
);
3506 Inside_Allocator
: Boolean := False;
3507 P
: Node_Id
:= Parent
(N
);
3510 if Is_Task_Type
(Ctype
) or else Has_Task
(Ctype
) then
3511 while Present
(P
) loop
3512 if Nkind
(P
) = N_Allocator
then
3513 Inside_Allocator
:= True;
3520 if not Inside_Init_Proc
and not Inside_Allocator
then
3521 Build_Activation_Chain_Entity
(N
);
3527 Build_Initialization_Call
(Loc
,
3528 Id_Ref
=> Make_Selected_Component
(Loc
,
3529 Prefix
=> New_Copy_Tree
(Target
),
3531 New_Occurrence_Of
(Selector
, Loc
)),
3532 Typ
=> Etype
(Selector
),
3534 With_Default_Init
=> True));
3536 -- Prepare for component assignment
3538 elsif Ekind
(Selector
) /= E_Discriminant
3539 or else Nkind
(N
) = N_Extension_Aggregate
3541 -- All the discriminants have now been assigned
3543 -- This is now a good moment to initialize and attach all the
3544 -- controllers. Their position may depend on the discriminants.
3546 if Ekind
(Selector
) /= E_Discriminant
then
3547 Generate_Finalization_Actions
;
3550 Comp_Type
:= Underlying_Type
(Etype
(Selector
));
3552 Make_Selected_Component
(Loc
,
3553 Prefix
=> New_Copy_Tree
(Target
),
3554 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
));
3556 if Nkind
(Expression
(Comp
)) = N_Qualified_Expression
then
3557 Expr_Q
:= Expression
(Expression
(Comp
));
3559 Expr_Q
:= Expression
(Comp
);
3562 -- Now either create the assignment or generate the code for the
3563 -- inner aggregate top-down.
3565 if Is_Delayed_Aggregate
(Expr_Q
) then
3567 -- We have the following case of aggregate nesting inside
3568 -- an object declaration:
3570 -- type Arr_Typ is array (Integer range <>) of ...;
3572 -- type Rec_Typ (...) is record
3573 -- Obj_Arr_Typ : Arr_Typ (A .. B);
3576 -- Obj_Rec_Typ : Rec_Typ := (...,
3577 -- Obj_Arr_Typ => (X => (...), Y => (...)));
3579 -- The length of the ranges of the aggregate and Obj_Add_Typ
3580 -- are equal (B - A = Y - X), but they do not coincide (X /=
3581 -- A and B /= Y). This case requires array sliding which is
3582 -- performed in the following manner:
3584 -- subtype Arr_Sub is Arr_Typ (X .. Y);
3586 -- Temp (X) := (...);
3588 -- Temp (Y) := (...);
3589 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
3591 if Ekind
(Comp_Type
) = E_Array_Subtype
3592 and then Is_Int_Range_Bounds
(Aggregate_Bounds
(Expr_Q
))
3593 and then Is_Int_Range_Bounds
(First_Index
(Comp_Type
))
3595 Compatible_Int_Bounds
3596 (Agg_Bounds
=> Aggregate_Bounds
(Expr_Q
),
3597 Typ_Bounds
=> First_Index
(Comp_Type
))
3599 -- Create the array subtype with bounds equal to those of
3600 -- the corresponding aggregate.
3603 SubE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
3605 SubD
: constant Node_Id
:=
3606 Make_Subtype_Declaration
(Loc
,
3607 Defining_Identifier
=> SubE
,
3608 Subtype_Indication
=>
3609 Make_Subtype_Indication
(Loc
,
3611 New_Occurrence_Of
(Etype
(Comp_Type
), Loc
),
3613 Make_Index_Or_Discriminant_Constraint
3615 Constraints
=> New_List
(
3617 (Aggregate_Bounds
(Expr_Q
))))));
3619 -- Create a temporary array of the above subtype which
3620 -- will be used to capture the aggregate assignments.
3622 TmpE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A', N
);
3624 TmpD
: constant Node_Id
:=
3625 Make_Object_Declaration
(Loc
,
3626 Defining_Identifier
=> TmpE
,
3627 Object_Definition
=> New_Occurrence_Of
(SubE
, Loc
));
3630 Set_No_Initialization
(TmpD
);
3631 Append_To
(L
, SubD
);
3632 Append_To
(L
, TmpD
);
3634 -- Expand aggregate into assignments to the temp array
3637 Late_Expansion
(Expr_Q
, Comp_Type
,
3638 New_Occurrence_Of
(TmpE
, Loc
)));
3643 Make_Assignment_Statement
(Loc
,
3644 Name
=> New_Copy_Tree
(Comp_Expr
),
3645 Expression
=> New_Occurrence_Of
(TmpE
, Loc
)));
3648 -- Normal case (sliding not required)
3652 Late_Expansion
(Expr_Q
, Comp_Type
, Comp_Expr
));
3655 -- Expr_Q is not delayed aggregate
3658 if Has_Discriminants
(Typ
) then
3659 Replace_Discriminants
(Expr_Q
);
3661 -- If the component is an array type that depends on
3662 -- discriminants, and the expression is a single Others
3663 -- clause, create an explicit subtype for it because the
3664 -- backend has troubles recovering the actual bounds.
3666 if Nkind
(Expr_Q
) = N_Aggregate
3667 and then Is_Array_Type
(Comp_Type
)
3668 and then Present
(Component_Associations
(Expr_Q
))
3671 Assoc
: constant Node_Id
:=
3672 First
(Component_Associations
(Expr_Q
));
3676 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
3679 Build_Actual_Subtype_Of_Component
3680 (Comp_Type
, Comp_Expr
);
3682 -- If the component type does not in fact depend on
3683 -- discriminants, the subtype declaration is empty.
3685 if Present
(Decl
) then
3686 Append_To
(L
, Decl
);
3687 Set_Etype
(Comp_Expr
, Defining_Entity
(Decl
));
3694 if Modify_Tree_For_C
3695 and then Nkind
(Expr_Q
) = N_Aggregate
3696 and then Is_Array_Type
(Etype
(Expr_Q
))
3697 and then Present
(First_Index
(Etype
(Expr_Q
)))
3700 Expr_Q_Type
: constant Node_Id
:= Etype
(Expr_Q
);
3703 Build_Array_Aggr_Code
3705 Ctype
=> Component_Type
(Expr_Q_Type
),
3706 Index
=> First_Index
(Expr_Q_Type
),
3709 Is_Scalar_Type
(Component_Type
(Expr_Q_Type
))));
3713 -- Handle an initialization expression of a controlled type
3714 -- in case it denotes a function call. In general such a
3715 -- scenario will produce a transient scope, but this will
3716 -- lead to wrong order of initialization, adjustment, and
3717 -- finalization in the context of aggregates.
3719 -- Target.Comp := Ctrl_Func_Call;
3722 -- Trans_Obj : ... := Ctrl_Func_Call; -- object
3723 -- Target.Comp := Trans_Obj;
3724 -- Finalize (Trans_Obj);
3726 -- Target.Comp._tag := ...;
3727 -- Adjust (Target.Comp);
3729 -- In the example above, the call to Finalize occurs too
3730 -- early and as a result it may leave the record component
3731 -- in a bad state. Finalization of the transient object
3732 -- should really happen after adjustment.
3734 -- To avoid this scenario, perform in-place side-effect
3735 -- removal of the function call. This eliminates the
3736 -- transient property of the function result and ensures
3737 -- correct order of actions.
3739 -- Res : ... := Ctrl_Func_Call;
3740 -- Target.Comp := Res;
3741 -- Target.Comp._tag := ...;
3742 -- Adjust (Target.Comp);
3745 if Needs_Finalization
(Comp_Type
)
3746 and then Nkind
(Expr_Q
) /= N_Aggregate
3748 Initialize_Ctrl_Record_Component
3749 (Rec_Comp
=> Comp_Expr
,
3750 Comp_Typ
=> Etype
(Selector
),
3751 Init_Expr
=> Expr_Q
,
3754 -- Otherwise perform single component initialization
3757 Initialize_Record_Component
3758 (Rec_Comp
=> Comp_Expr
,
3759 Comp_Typ
=> Etype
(Selector
),
3760 Init_Expr
=> Expr_Q
,
3766 -- comment would be good here ???
3768 elsif Ekind
(Selector
) = E_Discriminant
3769 and then Nkind
(N
) /= N_Extension_Aggregate
3770 and then Nkind
(Parent
(N
)) = N_Component_Association
3771 and then Is_Constrained
(Typ
)
3773 -- We must check that the discriminant value imposed by the
3774 -- context is the same as the value given in the subaggregate,
3775 -- because after the expansion into assignments there is no
3776 -- record on which to perform a regular discriminant check.
3783 D_Val
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3784 Disc
:= First_Discriminant
(Typ
);
3785 while Chars
(Disc
) /= Chars
(Selector
) loop
3786 Next_Discriminant
(Disc
);
3790 pragma Assert
(Present
(D_Val
));
3792 -- This check cannot performed for components that are
3793 -- constrained by a current instance, because this is not a
3794 -- value that can be compared with the actual constraint.
3796 if Nkind
(Node
(D_Val
)) /= N_Attribute_Reference
3797 or else not Is_Entity_Name
(Prefix
(Node
(D_Val
)))
3798 or else not Is_Type
(Entity
(Prefix
(Node
(D_Val
))))
3801 Make_Raise_Constraint_Error
(Loc
,
3804 Left_Opnd
=> New_Copy_Tree
(Node
(D_Val
)),
3805 Right_Opnd
=> Expression
(Comp
)),
3806 Reason
=> CE_Discriminant_Check_Failed
));
3809 -- Find self-reference in previous discriminant assignment,
3810 -- and replace with proper expression.
3817 while Present
(Ass
) loop
3818 if Nkind
(Ass
) = N_Assignment_Statement
3819 and then Nkind
(Name
(Ass
)) = N_Selected_Component
3820 and then Chars
(Selector_Name
(Name
(Ass
))) =
3824 (Ass
, New_Copy_Tree
(Expression
(Comp
)));
3837 -- If the type is tagged, the tag needs to be initialized (unless we
3838 -- are in VM-mode where tags are implicit). It is done late in the
3839 -- initialization process because in some cases, we call the init
3840 -- proc of an ancestor which will not leave out the right tag.
3842 if Ancestor_Is_Expression
then
3845 -- For CPP types we generated a call to the C++ default constructor
3846 -- before the components have been initialized to ensure the proper
3847 -- initialization of the _Tag component (see above).
3849 elsif Is_CPP_Class
(Typ
) then
3852 elsif Is_Tagged_Type
(Typ
) and then Tagged_Type_Expansion
then
3854 Make_OK_Assignment_Statement
(Loc
,
3856 Make_Selected_Component
(Loc
,
3857 Prefix
=> New_Copy_Tree
(Target
),
3860 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
3863 Unchecked_Convert_To
(RTE
(RE_Tag
),
3865 (Node
(First_Elmt
(Access_Disp_Table
(Base_Type
(Typ
)))),
3868 Append_To
(L
, Instr
);
3870 -- Ada 2005 (AI-251): If the tagged type has been derived from an
3871 -- abstract interfaces we must also initialize the tags of the
3872 -- secondary dispatch tables.
3874 if Has_Interfaces
(Base_Type
(Typ
)) then
3876 (Typ
=> Base_Type
(Typ
),
3879 Init_Tags_List
=> L
);
3883 -- If the controllers have not been initialized yet (by lack of non-
3884 -- discriminant components), let's do it now.
3886 Generate_Finalization_Actions
;
3889 end Build_Record_Aggr_Code
;
3891 ---------------------------------------
3892 -- Collect_Initialization_Statements --
3893 ---------------------------------------
3895 procedure Collect_Initialization_Statements
3898 Node_After
: Node_Id
)
3900 Loc
: constant Source_Ptr
:= Sloc
(N
);
3901 Init_Actions
: constant List_Id
:= New_List
;
3902 Init_Node
: Node_Id
;
3903 Comp_Stmt
: Node_Id
;
3906 -- Nothing to do if Obj is already frozen, as in this case we known we
3907 -- won't need to move the initialization statements about later on.
3909 if Is_Frozen
(Obj
) then
3914 while Next
(Init_Node
) /= Node_After
loop
3915 Append_To
(Init_Actions
, Remove_Next
(Init_Node
));
3918 if not Is_Empty_List
(Init_Actions
) then
3919 Comp_Stmt
:= Make_Compound_Statement
(Loc
, Actions
=> Init_Actions
);
3920 Insert_Action_After
(Init_Node
, Comp_Stmt
);
3921 Set_Initialization_Statements
(Obj
, Comp_Stmt
);
3923 end Collect_Initialization_Statements
;
3925 -------------------------------
3926 -- Convert_Aggr_In_Allocator --
3927 -------------------------------
3929 procedure Convert_Aggr_In_Allocator
3934 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3935 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3936 Temp
: constant Entity_Id
:= Defining_Identifier
(Decl
);
3938 Occ
: constant Node_Id
:=
3939 Unchecked_Convert_To
(Typ
,
3940 Make_Explicit_Dereference
(Loc
, New_Occurrence_Of
(Temp
, Loc
)));
3943 if Is_Array_Type
(Typ
) then
3944 Convert_Array_Aggr_In_Allocator
(Decl
, Aggr
, Occ
);
3946 elsif Has_Default_Init_Comps
(Aggr
) then
3948 L
: constant List_Id
:= New_List
;
3949 Init_Stmts
: List_Id
;
3952 Init_Stmts
:= Late_Expansion
(Aggr
, Typ
, Occ
);
3954 if Has_Task
(Typ
) then
3955 Build_Task_Allocate_Block_With_Init_Stmts
(L
, Aggr
, Init_Stmts
);
3956 Insert_Actions
(Alloc
, L
);
3958 Insert_Actions
(Alloc
, Init_Stmts
);
3963 Insert_Actions
(Alloc
, Late_Expansion
(Aggr
, Typ
, Occ
));
3965 end Convert_Aggr_In_Allocator
;
3967 --------------------------------
3968 -- Convert_Aggr_In_Assignment --
3969 --------------------------------
3971 procedure Convert_Aggr_In_Assignment
(N
: Node_Id
) is
3972 Aggr
: Node_Id
:= Expression
(N
);
3973 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3974 Occ
: constant Node_Id
:= New_Copy_Tree
(Name
(N
));
3977 if Nkind
(Aggr
) = N_Qualified_Expression
then
3978 Aggr
:= Expression
(Aggr
);
3981 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3982 end Convert_Aggr_In_Assignment
;
3984 ---------------------------------
3985 -- Convert_Aggr_In_Object_Decl --
3986 ---------------------------------
3988 procedure Convert_Aggr_In_Object_Decl
(N
: Node_Id
) is
3989 Obj
: constant Entity_Id
:= Defining_Identifier
(N
);
3990 Aggr
: Node_Id
:= Expression
(N
);
3991 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3992 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3993 Occ
: constant Node_Id
:= New_Occurrence_Of
(Obj
, Loc
);
3995 function Discriminants_Ok
return Boolean;
3996 -- If the object type is constrained, the discriminants in the
3997 -- aggregate must be checked against the discriminants of the subtype.
3998 -- This cannot be done using Apply_Discriminant_Checks because after
3999 -- expansion there is no aggregate left to check.
4001 ----------------------
4002 -- Discriminants_Ok --
4003 ----------------------
4005 function Discriminants_Ok
return Boolean is
4006 Cond
: Node_Id
:= Empty
;
4015 D
:= First_Discriminant
(Typ
);
4016 Disc1
:= First_Elmt
(Discriminant_Constraint
(Typ
));
4017 Disc2
:= First_Elmt
(Discriminant_Constraint
(Etype
(Obj
)));
4018 while Present
(Disc1
) and then Present
(Disc2
) loop
4019 Val1
:= Node
(Disc1
);
4020 Val2
:= Node
(Disc2
);
4022 if not Is_OK_Static_Expression
(Val1
)
4023 or else not Is_OK_Static_Expression
(Val2
)
4025 Check
:= Make_Op_Ne
(Loc
,
4026 Left_Opnd
=> Duplicate_Subexpr
(Val1
),
4027 Right_Opnd
=> Duplicate_Subexpr
(Val2
));
4033 Cond
:= Make_Or_Else
(Loc
,
4035 Right_Opnd
=> Check
);
4038 elsif Expr_Value
(Val1
) /= Expr_Value
(Val2
) then
4039 Apply_Compile_Time_Constraint_Error
(Aggr
,
4040 Msg
=> "incorrect value for discriminant&??",
4041 Reason
=> CE_Discriminant_Check_Failed
,
4046 Next_Discriminant
(D
);
4051 -- If any discriminant constraint is nonstatic, emit a check
4053 if Present
(Cond
) then
4055 Make_Raise_Constraint_Error
(Loc
,
4057 Reason
=> CE_Discriminant_Check_Failed
));
4061 end Discriminants_Ok
;
4063 -- Start of processing for Convert_Aggr_In_Object_Decl
4066 Set_Assignment_OK
(Occ
);
4068 if Nkind
(Aggr
) = N_Qualified_Expression
then
4069 Aggr
:= Expression
(Aggr
);
4072 if Has_Discriminants
(Typ
)
4073 and then Typ
/= Etype
(Obj
)
4074 and then Is_Constrained
(Etype
(Obj
))
4075 and then not Discriminants_Ok
4080 -- If the context is an extended return statement, it has its own
4081 -- finalization machinery (i.e. works like a transient scope) and
4082 -- we do not want to create an additional one, because objects on
4083 -- the finalization list of the return must be moved to the caller's
4084 -- finalization list to complete the return.
4086 -- However, if the aggregate is limited, it is built in place, and the
4087 -- controlled components are not assigned to intermediate temporaries
4088 -- so there is no need for a transient scope in this case either.
4090 if Requires_Transient_Scope
(Typ
)
4091 and then Ekind
(Current_Scope
) /= E_Return_Statement
4092 and then not Is_Limited_Type
(Typ
)
4094 Establish_Transient_Scope
(Aggr
, Manage_Sec_Stack
=> False);
4098 Node_After
: constant Node_Id
:= Next
(N
);
4100 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
4101 Collect_Initialization_Statements
(Obj
, N
, Node_After
);
4104 Set_No_Initialization
(N
);
4105 Initialize_Discriminants
(N
, Typ
);
4106 end Convert_Aggr_In_Object_Decl
;
4108 -------------------------------------
4109 -- Convert_Array_Aggr_In_Allocator --
4110 -------------------------------------
4112 procedure Convert_Array_Aggr_In_Allocator
4117 Aggr_Code
: List_Id
;
4118 Typ
: constant Entity_Id
:= Etype
(Aggr
);
4119 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
4122 -- The target is an explicit dereference of the allocated object.
4123 -- Generate component assignments to it, as for an aggregate that
4124 -- appears on the right-hand side of an assignment statement.
4127 Build_Array_Aggr_Code
(Aggr
,
4129 Index
=> First_Index
(Typ
),
4131 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
4133 Insert_Actions_After
(Decl
, Aggr_Code
);
4134 end Convert_Array_Aggr_In_Allocator
;
4136 ----------------------------
4137 -- Convert_To_Assignments --
4138 ----------------------------
4140 procedure Convert_To_Assignments
(N
: Node_Id
; Typ
: Entity_Id
) is
4141 Loc
: constant Source_Ptr
:= Sloc
(N
);
4145 Aggr_Code
: List_Id
;
4147 Target_Expr
: Node_Id
;
4148 Parent_Kind
: Node_Kind
;
4149 Unc_Decl
: Boolean := False;
4150 Parent_Node
: Node_Id
;
4153 pragma Assert
(Nkind_In
(N
, N_Aggregate
, N_Extension_Aggregate
));
4154 pragma Assert
(not Is_Static_Dispatch_Table_Aggregate
(N
));
4155 pragma Assert
(Is_Record_Type
(Typ
));
4157 Parent_Node
:= Parent
(N
);
4158 Parent_Kind
:= Nkind
(Parent_Node
);
4160 if Parent_Kind
= N_Qualified_Expression
then
4161 -- Check if we are in an unconstrained declaration because in this
4162 -- case the current delayed expansion mechanism doesn't work when
4163 -- the declared object size depends on the initializing expr.
4165 Parent_Node
:= Parent
(Parent_Node
);
4166 Parent_Kind
:= Nkind
(Parent_Node
);
4168 if Parent_Kind
= N_Object_Declaration
then
4170 not Is_Entity_Name
(Object_Definition
(Parent_Node
))
4171 or else (Nkind
(N
) = N_Aggregate
4174 (Entity
(Object_Definition
(Parent_Node
))))
4175 or else Is_Class_Wide_Type
4176 (Entity
(Object_Definition
(Parent_Node
)));
4180 -- Just set the Delay flag in the cases where the transformation will be
4181 -- done top down from above.
4185 -- Internal aggregate (transformed when expanding the parent)
4187 or else Parent_Kind
= N_Aggregate
4188 or else Parent_Kind
= N_Extension_Aggregate
4189 or else Parent_Kind
= N_Component_Association
4191 -- Allocator (see Convert_Aggr_In_Allocator)
4193 or else Parent_Kind
= N_Allocator
4195 -- Object declaration (see Convert_Aggr_In_Object_Decl)
4197 or else (Parent_Kind
= N_Object_Declaration
and then not Unc_Decl
)
4199 -- Safe assignment (see Convert_Aggr_Assignments). So far only the
4200 -- assignments in init procs are taken into account.
4202 or else (Parent_Kind
= N_Assignment_Statement
4203 and then Inside_Init_Proc
)
4205 -- (Ada 2005) An inherently limited type in a return statement, which
4206 -- will be handled in a build-in-place fashion, and may be rewritten
4207 -- as an extended return and have its own finalization machinery.
4208 -- In the case of a simple return, the aggregate needs to be delayed
4209 -- until the scope for the return statement has been created, so
4210 -- that any finalization chain will be associated with that scope.
4211 -- For extended returns, we delay expansion to avoid the creation
4212 -- of an unwanted transient scope that could result in premature
4213 -- finalization of the return object (which is built in place
4214 -- within the caller's scope).
4216 or else Is_Build_In_Place_Aggregate_Return
(N
)
4218 Set_Expansion_Delayed
(N
);
4222 -- Otherwise, if a transient scope is required, create it now. If we
4223 -- are within an initialization procedure do not create such, because
4224 -- the target of the assignment must not be declared within a local
4225 -- block, and because cleanup will take place on return from the
4226 -- initialization procedure.
4228 -- Should the condition be more restrictive ???
4230 if Requires_Transient_Scope
(Typ
) and then not Inside_Init_Proc
then
4231 Establish_Transient_Scope
(N
, Manage_Sec_Stack
=> False);
4234 -- If the aggregate is nonlimited, create a temporary. If it is limited
4235 -- and context is an assignment, this is a subaggregate for an enclosing
4236 -- aggregate being expanded. It must be built in place, so use target of
4237 -- the current assignment.
4239 if Is_Limited_Type
(Typ
)
4240 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
4242 Target_Expr
:= New_Copy_Tree
(Name
(Parent
(N
)));
4243 Insert_Actions
(Parent
(N
),
4244 Build_Record_Aggr_Code
(N
, Typ
, Target_Expr
));
4245 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
4248 Temp
:= Make_Temporary
(Loc
, 'A', N
);
4250 -- If the type inherits unknown discriminants, use the view with
4251 -- known discriminants if available.
4253 if Has_Unknown_Discriminants
(Typ
)
4254 and then Present
(Underlying_Record_View
(Typ
))
4256 T
:= Underlying_Record_View
(Typ
);
4262 Make_Object_Declaration
(Loc
,
4263 Defining_Identifier
=> Temp
,
4264 Object_Definition
=> New_Occurrence_Of
(T
, Loc
));
4266 Set_No_Initialization
(Instr
);
4267 Insert_Action
(N
, Instr
);
4268 Initialize_Discriminants
(Instr
, T
);
4270 Target_Expr
:= New_Occurrence_Of
(Temp
, Loc
);
4271 Aggr_Code
:= Build_Record_Aggr_Code
(N
, T
, Target_Expr
);
4273 -- Save the last assignment statement associated with the aggregate
4274 -- when building a controlled object. This reference is utilized by
4275 -- the finalization machinery when marking an object as successfully
4278 if Needs_Finalization
(T
) then
4279 Set_Last_Aggregate_Assignment
(Temp
, Last
(Aggr_Code
));
4282 Insert_Actions
(N
, Aggr_Code
);
4283 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
4284 Analyze_And_Resolve
(N
, T
);
4286 end Convert_To_Assignments
;
4288 ---------------------------
4289 -- Convert_To_Positional --
4290 ---------------------------
4292 procedure Convert_To_Positional
4294 Max_Others_Replicate
: Nat
:= 32;
4295 Handle_Bit_Packed
: Boolean := False)
4297 Typ
: constant Entity_Id
:= Etype
(N
);
4299 Static_Components
: Boolean := True;
4301 procedure Check_Static_Components
;
4302 -- Check whether all components of the aggregate are compile-time known
4303 -- values, and can be passed as is to the back-end without further
4305 -- An Iterated_Component_Association is treated as nonstatic, but there
4306 -- are possibilities for optimization here.
4311 Ixb
: Node_Id
) return Boolean;
4312 -- Convert the aggregate into a purely positional form if possible. On
4313 -- entry the bounds of all dimensions are known to be static, and the
4314 -- total number of components is safe enough to expand.
4316 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean;
4317 -- Return True iff the array N is flat (which is not trivial in the case
4318 -- of multidimensional aggregates).
4320 -----------------------------
4321 -- Check_Static_Components --
4322 -----------------------------
4324 -- Could use some comments in this body ???
4326 procedure Check_Static_Components
is
4330 Static_Components
:= True;
4332 if Nkind
(N
) = N_String_Literal
then
4335 elsif Present
(Expressions
(N
)) then
4336 Expr
:= First
(Expressions
(N
));
4337 while Present
(Expr
) loop
4338 if Nkind
(Expr
) /= N_Aggregate
4339 or else not Compile_Time_Known_Aggregate
(Expr
)
4340 or else Expansion_Delayed
(Expr
)
4342 Static_Components
:= False;
4350 if Nkind
(N
) = N_Aggregate
4351 and then Present
(Component_Associations
(N
))
4353 Expr
:= First
(Component_Associations
(N
));
4354 while Present
(Expr
) loop
4355 if Nkind_In
(Expression
(Expr
), N_Integer_Literal
,
4360 elsif Is_Entity_Name
(Expression
(Expr
))
4361 and then Present
(Entity
(Expression
(Expr
)))
4362 and then Ekind
(Entity
(Expression
(Expr
))) =
4363 E_Enumeration_Literal
4367 elsif Nkind
(Expression
(Expr
)) /= N_Aggregate
4368 or else not Compile_Time_Known_Aggregate
(Expression
(Expr
))
4369 or else Expansion_Delayed
(Expression
(Expr
))
4370 or else Nkind
(Expr
) = N_Iterated_Component_Association
4371 or else Nkind
(Expr
) = N_Quantified_Expression
4373 Static_Components
:= False;
4380 end Check_Static_Components
;
4389 Ixb
: Node_Id
) return Boolean
4391 Loc
: constant Source_Ptr
:= Sloc
(N
);
4392 Blo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ixb
));
4393 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ix
));
4394 Hi
: constant Node_Id
:= Type_High_Bound
(Etype
(Ix
));
4398 Others_Present
: Boolean := False;
4401 if Nkind
(Original_Node
(N
)) = N_String_Literal
then
4405 if not Compile_Time_Known_Value
(Lo
)
4406 or else not Compile_Time_Known_Value
(Hi
)
4411 Lov
:= Expr_Value
(Lo
);
4412 Hiv
:= Expr_Value
(Hi
);
4414 -- Check if there is an others choice
4416 if Present
(Component_Associations
(N
)) then
4422 Assoc
:= First
(Component_Associations
(N
));
4423 while Present
(Assoc
) loop
4425 -- If this is a box association, flattening is in general
4426 -- not possible because at this point we cannot tell if the
4427 -- default is static or even exists.
4429 if Box_Present
(Assoc
) then
4432 elsif Nkind
(Assoc
) = N_Iterated_Component_Association
then
4436 Choice
:= First
(Choice_List
(Assoc
));
4438 while Present
(Choice
) loop
4439 if Nkind
(Choice
) = N_Others_Choice
then
4440 Others_Present
:= True;
4451 -- If the low bound is not known at compile time and others is not
4452 -- present we can proceed since the bounds can be obtained from the
4456 or else (not Compile_Time_Known_Value
(Blo
) and then Others_Present
)
4461 -- Determine if set of alternatives is suitable for conversion and
4462 -- build an array containing the values in sequence.
4465 Vals
: array (UI_To_Int
(Lov
) .. UI_To_Int
(Hiv
))
4466 of Node_Id
:= (others => Empty
);
4467 -- The values in the aggregate sorted appropriately
4470 -- Same data as Vals in list form
4473 -- Used to validate Max_Others_Replicate limit
4476 Num
: Int
:= UI_To_Int
(Lov
);
4482 if Present
(Expressions
(N
)) then
4483 Elmt
:= First
(Expressions
(N
));
4484 while Present
(Elmt
) loop
4485 if Nkind
(Elmt
) = N_Aggregate
4486 and then Present
(Next_Index
(Ix
))
4488 not Flatten
(Elmt
, Next_Index
(Ix
), Next_Index
(Ixb
))
4493 Vals
(Num
) := Relocate_Node
(Elmt
);
4500 if No
(Component_Associations
(N
)) then
4504 Elmt
:= First
(Component_Associations
(N
));
4506 if Nkind
(Expression
(Elmt
)) = N_Aggregate
then
4507 if Present
(Next_Index
(Ix
))
4510 (Expression
(Elmt
), Next_Index
(Ix
), Next_Index
(Ixb
))
4516 Component_Loop
: while Present
(Elmt
) loop
4517 Choice
:= First
(Choice_List
(Elmt
));
4518 Choice_Loop
: while Present
(Choice
) loop
4520 -- If we have an others choice, fill in the missing elements
4521 -- subject to the limit established by Max_Others_Replicate.
4522 -- If the expression involves a construct that generates
4523 -- a loop, we must generate individual assignmentw and
4524 -- no flattening is possible.
4526 if Nkind
(Choice
) = N_Others_Choice
then
4529 if Nkind_In
(Expression
(Elmt
),
4530 N_Quantified_Expression
,
4531 N_Iterated_Component_Association
)
4536 for J
in Vals
'Range loop
4537 if No
(Vals
(J
)) then
4538 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
4539 Rep_Count
:= Rep_Count
+ 1;
4541 -- Check for maximum others replication. Note that
4542 -- we skip this test if either of the restrictions
4543 -- No_Elaboration_Code or No_Implicit_Loops is
4544 -- active, if this is a preelaborable unit or
4545 -- a predefined unit, or if the unit must be
4546 -- placed in data memory. This also ensures that
4547 -- predefined units get the same level of constant
4548 -- folding in Ada 95 and Ada 2005, where their
4549 -- categorization has changed.
4552 P
: constant Entity_Id
:=
4553 Cunit_Entity
(Current_Sem_Unit
);
4556 -- Check if duplication OK and if so continue
4559 if Restriction_Active
(No_Elaboration_Code
)
4560 or else Restriction_Active
(No_Implicit_Loops
)
4562 (Ekind
(Current_Scope
) = E_Package
4563 and then Static_Elaboration_Desired
4565 or else Is_Preelaborated
(P
)
4566 or else (Ekind
(P
) = E_Package_Body
4568 Is_Preelaborated
(Spec_Entity
(P
)))
4570 Is_Predefined_Unit
(Get_Source_Unit
(P
))
4574 -- If duplication not OK, then we return False
4575 -- if the replication count is too high
4577 elsif Rep_Count
> Max_Others_Replicate
then
4580 -- Continue on if duplication not OK, but the
4581 -- replication count is not excessive.
4591 and then Warn_On_Redundant_Constructs
4593 Error_Msg_N
("there are no others?r?", Elmt
);
4596 exit Component_Loop
;
4598 -- Case of a subtype mark, identifier or expanded name
4600 elsif Is_Entity_Name
(Choice
)
4601 and then Is_Type
(Entity
(Choice
))
4603 Lo
:= Type_Low_Bound
(Etype
(Choice
));
4604 Hi
:= Type_High_Bound
(Etype
(Choice
));
4606 -- Case of subtype indication
4608 elsif Nkind
(Choice
) = N_Subtype_Indication
then
4609 Lo
:= Low_Bound
(Range_Expression
(Constraint
(Choice
)));
4610 Hi
:= High_Bound
(Range_Expression
(Constraint
(Choice
)));
4614 elsif Nkind
(Choice
) = N_Range
then
4615 Lo
:= Low_Bound
(Choice
);
4616 Hi
:= High_Bound
(Choice
);
4618 -- Normal subexpression case
4620 else pragma Assert
(Nkind
(Choice
) in N_Subexpr
);
4621 if not Compile_Time_Known_Value
(Choice
) then
4625 Choice_Index
:= UI_To_Int
(Expr_Value
(Choice
));
4627 if Choice_Index
in Vals
'Range then
4628 Vals
(Choice_Index
) :=
4629 New_Copy_Tree
(Expression
(Elmt
));
4632 -- Choice is statically out-of-range, will be
4633 -- rewritten to raise Constraint_Error.
4641 -- Range cases merge with Lo,Hi set
4643 if not Compile_Time_Known_Value
(Lo
)
4645 not Compile_Time_Known_Value
(Hi
)
4650 for J
in UI_To_Int
(Expr_Value
(Lo
)) ..
4651 UI_To_Int
(Expr_Value
(Hi
))
4653 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
4659 end loop Choice_Loop
;
4662 end loop Component_Loop
;
4664 -- If we get here the conversion is possible
4667 for J
in Vals
'Range loop
4668 Append
(Vals
(J
), Vlist
);
4671 Rewrite
(N
, Make_Aggregate
(Loc
, Expressions
=> Vlist
));
4672 Set_Aggregate_Bounds
(N
, Aggregate_Bounds
(Original_Node
(N
)));
4681 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean is
4688 elsif Nkind
(N
) = N_Aggregate
then
4689 if Present
(Component_Associations
(N
)) then
4693 Elmt
:= First
(Expressions
(N
));
4694 while Present
(Elmt
) loop
4695 if not Is_Flat
(Elmt
, Dims
- 1) then
4709 -- Start of processing for Convert_To_Positional
4712 -- Only convert to positional when generating C in case of an
4713 -- object declaration, this is the only case where aggregates are
4716 if Modify_Tree_For_C
and then not In_Object_Declaration
(N
) then
4720 -- Ada 2005 (AI-287): Do not convert in case of default initialized
4721 -- components because in this case will need to call the corresponding
4724 if Has_Default_Init_Comps
(N
) then
4728 if Is_Flat
(N
, Number_Dimensions
(Typ
)) then
4732 if Is_Bit_Packed_Array
(Typ
) and then not Handle_Bit_Packed
then
4736 -- Do not convert to positional if controlled components are involved
4737 -- since these require special processing
4739 if Has_Controlled_Component
(Typ
) then
4743 Check_Static_Components
;
4745 -- If the size is known, or all the components are static, try to
4746 -- build a fully positional aggregate.
4748 -- The size of the type may not be known for an aggregate with
4749 -- discriminated array components, but if the components are static
4750 -- it is still possible to verify statically that the length is
4751 -- compatible with the upper bound of the type, and therefore it is
4752 -- worth flattening such aggregates as well.
4754 -- For now the back-end expands these aggregates into individual
4755 -- assignments to the target anyway, but it is conceivable that
4756 -- it will eventually be able to treat such aggregates statically???
4758 if Aggr_Size_OK
(N
, Typ
)
4759 and then Flatten
(N
, First_Index
(Typ
), First_Index
(Base_Type
(Typ
)))
4761 if Static_Components
then
4762 Set_Compile_Time_Known_Aggregate
(N
);
4763 Set_Expansion_Delayed
(N
, False);
4766 Analyze_And_Resolve
(N
, Typ
);
4769 -- If Static_Elaboration_Desired has been specified, diagnose aggregates
4770 -- that will still require initialization code.
4772 if (Ekind
(Current_Scope
) = E_Package
4773 and then Static_Elaboration_Desired
(Current_Scope
))
4774 and then Nkind
(Parent
(N
)) = N_Object_Declaration
4780 if Nkind
(N
) = N_Aggregate
and then Present
(Expressions
(N
)) then
4781 Expr
:= First
(Expressions
(N
));
4782 while Present
(Expr
) loop
4783 if Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
)
4785 (Is_Entity_Name
(Expr
)
4786 and then Ekind
(Entity
(Expr
)) = E_Enumeration_Literal
)
4792 ("non-static object requires elaboration code??", N
);
4799 if Present
(Component_Associations
(N
)) then
4800 Error_Msg_N
("object requires elaboration code??", N
);
4805 end Convert_To_Positional
;
4807 ----------------------------
4808 -- Expand_Array_Aggregate --
4809 ----------------------------
4811 -- Array aggregate expansion proceeds as follows:
4813 -- 1. If requested we generate code to perform all the array aggregate
4814 -- bound checks, specifically
4816 -- (a) Check that the index range defined by aggregate bounds is
4817 -- compatible with corresponding index subtype.
4819 -- (b) If an others choice is present check that no aggregate
4820 -- index is outside the bounds of the index constraint.
4822 -- (c) For multidimensional arrays make sure that all subaggregates
4823 -- corresponding to the same dimension have the same bounds.
4825 -- 2. Check for packed array aggregate which can be converted to a
4826 -- constant so that the aggregate disappears completely.
4828 -- 3. Check case of nested aggregate. Generally nested aggregates are
4829 -- handled during the processing of the parent aggregate.
4831 -- 4. Check if the aggregate can be statically processed. If this is the
4832 -- case pass it as is to Gigi. Note that a necessary condition for
4833 -- static processing is that the aggregate be fully positional.
4835 -- 5. If in place aggregate expansion is possible (i.e. no need to create
4836 -- a temporary) then mark the aggregate as such and return. Otherwise
4837 -- create a new temporary and generate the appropriate initialization
4840 procedure Expand_Array_Aggregate
(N
: Node_Id
) is
4841 Loc
: constant Source_Ptr
:= Sloc
(N
);
4843 Typ
: constant Entity_Id
:= Etype
(N
);
4844 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
4845 -- Typ is the correct constrained array subtype of the aggregate
4846 -- Ctyp is the corresponding component type.
4848 Aggr_Dimension
: constant Pos
:= Number_Dimensions
(Typ
);
4849 -- Number of aggregate index dimensions
4851 Aggr_Low
: array (1 .. Aggr_Dimension
) of Node_Id
;
4852 Aggr_High
: array (1 .. Aggr_Dimension
) of Node_Id
;
4853 -- Low and High bounds of the constraint for each aggregate index
4855 Aggr_Index_Typ
: array (1 .. Aggr_Dimension
) of Entity_Id
;
4856 -- The type of each index
4858 In_Place_Assign_OK_For_Declaration
: Boolean := False;
4859 -- True if we are to generate an in place assignment for a declaration
4861 Maybe_In_Place_OK
: Boolean;
4862 -- If the type is neither controlled nor packed and the aggregate
4863 -- is the expression in an assignment, assignment in place may be
4864 -- possible, provided other conditions are met on the LHS.
4866 Others_Present
: array (1 .. Aggr_Dimension
) of Boolean :=
4868 -- If Others_Present (J) is True, then there is an others choice in one
4869 -- of the subaggregates of N at dimension J.
4871 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean;
4872 -- Returns true if an aggregate assignment can be done by the back end
4874 procedure Build_Constrained_Type
(Positional
: Boolean);
4875 -- If the subtype is not static or unconstrained, build a constrained
4876 -- type using the computable sizes of the aggregate and its sub-
4879 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
);
4880 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
4883 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4884 -- Checks that in a multidimensional array aggregate all subaggregates
4885 -- corresponding to the same dimension have the same bounds. Sub_Aggr is
4886 -- an array subaggregate. Dim is the dimension corresponding to the
4889 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4890 -- Computes the values of array Others_Present. Sub_Aggr is the array
4891 -- subaggregate we start the computation from. Dim is the dimension
4892 -- corresponding to the subaggregate.
4894 function In_Place_Assign_OK
return Boolean;
4895 -- Simple predicate to determine whether an aggregate assignment can
4896 -- be done in place, because none of the new values can depend on the
4897 -- components of the target of the assignment.
4899 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4900 -- Checks that if an others choice is present in any subaggregate, no
4901 -- aggregate index is outside the bounds of the index constraint.
4902 -- Sub_Aggr is an array subaggregate. Dim is the dimension corresponding
4903 -- to the subaggregate.
4905 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean;
4906 -- In addition to Maybe_In_Place_OK, in order for an aggregate to be
4907 -- built directly into the target of the assignment it must be free
4910 ------------------------------------
4911 -- Aggr_Assignment_OK_For_Backend --
4912 ------------------------------------
4914 -- Backend processing by Gigi/gcc is possible only if all the following
4915 -- conditions are met:
4917 -- 1. N consists of a single OTHERS choice, possibly recursively
4919 -- 2. The array type has no null ranges (the purpose of this is to
4920 -- avoid a bogus warning for an out-of-range value).
4922 -- 3. The array type has no atomic components
4924 -- 4. The component type is elementary
4926 -- 5. The component size is a multiple of Storage_Unit
4928 -- 6. The component size is Storage_Unit or the value is of the form
4929 -- M * (1 + A**1 + A**2 + .. A**(K-1)) where A = 2**(Storage_Unit)
4930 -- and M in 1 .. A-1. This can also be viewed as K occurrences of
4931 -- the 8-bit value M, concatenated together.
4933 -- The ultimate goal is to generate a call to a fast memset routine
4934 -- specifically optimized for the target.
4936 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean is
4948 -- Recurse as far as possible to find the innermost component type
4952 while Is_Array_Type
(Ctyp
) loop
4953 if Nkind
(Expr
) /= N_Aggregate
4954 or else not Is_Others_Aggregate
(Expr
)
4959 Index
:= First_Index
(Ctyp
);
4960 while Present
(Index
) loop
4961 Get_Index_Bounds
(Index
, Low
, High
);
4963 if Is_Null_Range
(Low
, High
) then
4970 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4972 for J
in 1 .. Number_Dimensions
(Ctyp
) - 1 loop
4973 if Nkind
(Expr
) /= N_Aggregate
4974 or else not Is_Others_Aggregate
(Expr
)
4979 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4982 if Has_Atomic_Components
(Ctyp
) then
4986 Csiz
:= Component_Size
(Ctyp
);
4987 Ctyp
:= Component_Type
(Ctyp
);
4989 if Is_Atomic_Or_VFA
(Ctyp
) then
4994 -- An Iterated_Component_Association involves a loop (in most cases)
4995 -- and is never static.
4997 if Nkind
(Parent
(Expr
)) = N_Iterated_Component_Association
then
5001 -- Access types need to be dealt with specially
5003 if Is_Access_Type
(Ctyp
) then
5005 -- Component_Size is not set by Layout_Type if the component
5006 -- type is an access type ???
5008 Csiz
:= Esize
(Ctyp
);
5010 -- Fat pointers are rejected as they are not really elementary
5013 if Csiz
/= System_Address_Size
then
5017 -- The supported expressions are NULL and constants, others are
5018 -- rejected upfront to avoid being analyzed below, which can be
5019 -- problematic for some of them, for example allocators.
5021 if Nkind
(Expr
) /= N_Null
and then not Is_Entity_Name
(Expr
) then
5025 -- Scalar types are OK if their size is a multiple of Storage_Unit
5027 elsif Is_Scalar_Type
(Ctyp
) then
5028 if Csiz
mod System_Storage_Unit
/= 0 then
5032 -- Composite types are rejected
5038 -- The expression needs to be analyzed if True is returned
5040 Analyze_And_Resolve
(Expr
, Ctyp
);
5042 -- Strip away any conversions from the expression as they simply
5043 -- qualify the real expression.
5045 while Nkind_In
(Expr
, N_Unchecked_Type_Conversion
,
5048 Expr
:= Expression
(Expr
);
5051 Nunits
:= UI_To_Int
(Csiz
) / System_Storage_Unit
;
5057 if not Compile_Time_Known_Value
(Expr
) then
5061 -- The only supported value for floating point is 0.0
5063 if Is_Floating_Point_Type
(Ctyp
) then
5064 return Expr_Value_R
(Expr
) = Ureal_0
;
5067 -- For other types, we can look into the value as an integer
5069 Value
:= Expr_Value
(Expr
);
5071 if Has_Biased_Representation
(Ctyp
) then
5072 Value
:= Value
- Expr_Value
(Type_Low_Bound
(Ctyp
));
5075 -- Values 0 and -1 immediately satisfy the last check
5077 if Value
= Uint_0
or else Value
= Uint_Minus_1
then
5081 -- We need to work with an unsigned value
5084 Value
:= Value
+ 2**(System_Storage_Unit
* Nunits
);
5087 Remainder
:= Value
rem 2**System_Storage_Unit
;
5089 for J
in 1 .. Nunits
- 1 loop
5090 Value
:= Value
/ 2**System_Storage_Unit
;
5092 if Value
rem 2**System_Storage_Unit
/= Remainder
then
5098 end Aggr_Assignment_OK_For_Backend
;
5100 ----------------------------
5101 -- Build_Constrained_Type --
5102 ----------------------------
5104 procedure Build_Constrained_Type
(Positional
: Boolean) is
5105 Loc
: constant Source_Ptr
:= Sloc
(N
);
5106 Agg_Type
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
5109 Typ
: constant Entity_Id
:= Etype
(N
);
5110 Indexes
: constant List_Id
:= New_List
;
5115 -- If the aggregate is purely positional, all its subaggregates
5116 -- have the same size. We collect the dimensions from the first
5117 -- subaggregate at each level.
5122 for D
in 1 .. Number_Dimensions
(Typ
) loop
5123 Sub_Agg
:= First
(Expressions
(Sub_Agg
));
5127 while Present
(Comp
) loop
5134 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
5135 High_Bound
=> Make_Integer_Literal
(Loc
, Num
)));
5139 -- We know the aggregate type is unconstrained and the aggregate
5140 -- is not processable by the back end, therefore not necessarily
5141 -- positional. Retrieve each dimension bounds (computed earlier).
5143 for D
in 1 .. Number_Dimensions
(Typ
) loop
5146 Low_Bound
=> Aggr_Low
(D
),
5147 High_Bound
=> Aggr_High
(D
)));
5152 Make_Full_Type_Declaration
(Loc
,
5153 Defining_Identifier
=> Agg_Type
,
5155 Make_Constrained_Array_Definition
(Loc
,
5156 Discrete_Subtype_Definitions
=> Indexes
,
5157 Component_Definition
=>
5158 Make_Component_Definition
(Loc
,
5159 Aliased_Present
=> False,
5160 Subtype_Indication
=>
5161 New_Occurrence_Of
(Component_Type
(Typ
), Loc
))));
5163 Insert_Action
(N
, Decl
);
5165 Set_Etype
(N
, Agg_Type
);
5166 Set_Is_Itype
(Agg_Type
);
5167 Freeze_Itype
(Agg_Type
, N
);
5168 end Build_Constrained_Type
;
5174 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
) is
5181 Cond
: Node_Id
:= Empty
;
5184 Get_Index_Bounds
(Aggr_Bounds
, Aggr_Lo
, Aggr_Hi
);
5185 Get_Index_Bounds
(Index_Bounds
, Ind_Lo
, Ind_Hi
);
5187 -- Generate the following test:
5189 -- [constraint_error when
5190 -- Aggr_Lo <= Aggr_Hi and then
5191 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
5193 -- As an optimization try to see if some tests are trivially vacuous
5194 -- because we are comparing an expression against itself.
5196 if Aggr_Lo
= Ind_Lo
and then Aggr_Hi
= Ind_Hi
then
5199 elsif Aggr_Hi
= Ind_Hi
then
5202 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5203 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
));
5205 elsif Aggr_Lo
= Ind_Lo
then
5208 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
5209 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Hi
));
5216 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5217 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
)),
5221 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
5222 Right_Opnd
=> Duplicate_Subexpr
(Ind_Hi
)));
5225 if Present
(Cond
) then
5230 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5231 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
)),
5233 Right_Opnd
=> Cond
);
5235 Set_Analyzed
(Left_Opnd
(Left_Opnd
(Cond
)), False);
5236 Set_Analyzed
(Right_Opnd
(Left_Opnd
(Cond
)), False);
5238 Make_Raise_Constraint_Error
(Loc
,
5240 Reason
=> CE_Range_Check_Failed
));
5244 ----------------------------
5245 -- Check_Same_Aggr_Bounds --
5246 ----------------------------
5248 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
5249 Sub_Lo
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(Sub_Aggr
));
5250 Sub_Hi
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(Sub_Aggr
));
5251 -- The bounds of this specific subaggregate
5253 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
5254 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
5255 -- The bounds of the aggregate for this dimension
5257 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
5258 -- The index type for this dimension.xxx
5260 Cond
: Node_Id
:= Empty
;
5265 -- If index checks are on generate the test
5267 -- [constraint_error when
5268 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
5270 -- As an optimization try to see if some tests are trivially vacuos
5271 -- because we are comparing an expression against itself. Also for
5272 -- the first dimension the test is trivially vacuous because there
5273 -- is just one aggregate for dimension 1.
5275 if Index_Checks_Suppressed
(Ind_Typ
) then
5278 elsif Dim
= 1 or else (Aggr_Lo
= Sub_Lo
and then Aggr_Hi
= Sub_Hi
)
5282 elsif Aggr_Hi
= Sub_Hi
then
5285 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5286 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
));
5288 elsif Aggr_Lo
= Sub_Lo
then
5291 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
5292 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Hi
));
5299 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5300 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
)),
5304 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
5305 Right_Opnd
=> Duplicate_Subexpr
(Sub_Hi
)));
5308 if Present
(Cond
) then
5310 Make_Raise_Constraint_Error
(Loc
,
5312 Reason
=> CE_Length_Check_Failed
));
5315 -- Now look inside the subaggregate to see if there is more work
5317 if Dim
< Aggr_Dimension
then
5319 -- Process positional components
5321 if Present
(Expressions
(Sub_Aggr
)) then
5322 Expr
:= First
(Expressions
(Sub_Aggr
));
5323 while Present
(Expr
) loop
5324 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
5329 -- Process component associations
5331 if Present
(Component_Associations
(Sub_Aggr
)) then
5332 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5333 while Present
(Assoc
) loop
5334 Expr
:= Expression
(Assoc
);
5335 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
5340 end Check_Same_Aggr_Bounds
;
5342 ----------------------------
5343 -- Compute_Others_Present --
5344 ----------------------------
5346 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
5351 if Present
(Component_Associations
(Sub_Aggr
)) then
5352 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
5354 if Nkind
(First
(Choice_List
(Assoc
))) = N_Others_Choice
then
5355 Others_Present
(Dim
) := True;
5359 -- Now look inside the subaggregate to see if there is more work
5361 if Dim
< Aggr_Dimension
then
5363 -- Process positional components
5365 if Present
(Expressions
(Sub_Aggr
)) then
5366 Expr
:= First
(Expressions
(Sub_Aggr
));
5367 while Present
(Expr
) loop
5368 Compute_Others_Present
(Expr
, Dim
+ 1);
5373 -- Process component associations
5375 if Present
(Component_Associations
(Sub_Aggr
)) then
5376 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5377 while Present
(Assoc
) loop
5378 Expr
:= Expression
(Assoc
);
5379 Compute_Others_Present
(Expr
, Dim
+ 1);
5384 end Compute_Others_Present
;
5386 ------------------------
5387 -- In_Place_Assign_OK --
5388 ------------------------
5390 function In_Place_Assign_OK
return Boolean is
5398 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean;
5399 -- Check recursively that each component of a (sub)aggregate does not
5400 -- depend on the variable being assigned to.
5402 function Safe_Component
(Expr
: Node_Id
) return Boolean;
5403 -- Verify that an expression cannot depend on the variable being
5404 -- assigned to. Room for improvement here (but less than before).
5406 --------------------
5407 -- Safe_Aggregate --
5408 --------------------
5410 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean is
5414 if Nkind
(Parent
(Aggr
)) = N_Iterated_Component_Association
then
5418 if Present
(Expressions
(Aggr
)) then
5419 Expr
:= First
(Expressions
(Aggr
));
5420 while Present
(Expr
) loop
5421 if Nkind
(Expr
) = N_Aggregate
then
5422 if not Safe_Aggregate
(Expr
) then
5426 elsif not Safe_Component
(Expr
) then
5434 if Present
(Component_Associations
(Aggr
)) then
5435 Expr
:= First
(Component_Associations
(Aggr
));
5436 while Present
(Expr
) loop
5437 if Nkind
(Expression
(Expr
)) = N_Aggregate
then
5438 if not Safe_Aggregate
(Expression
(Expr
)) then
5442 -- If association has a box, no way to determine yet
5443 -- whether default can be assigned in place.
5445 elsif Box_Present
(Expr
) then
5448 elsif not Safe_Component
(Expression
(Expr
)) then
5459 --------------------
5460 -- Safe_Component --
5461 --------------------
5463 function Safe_Component
(Expr
: Node_Id
) return Boolean is
5464 Comp
: Node_Id
:= Expr
;
5466 function Check_Component
(Comp
: Node_Id
) return Boolean;
5467 -- Do the recursive traversal, after copy
5469 ---------------------
5470 -- Check_Component --
5471 ---------------------
5473 function Check_Component
(Comp
: Node_Id
) return Boolean is
5475 if Is_Overloaded
(Comp
) then
5479 return Compile_Time_Known_Value
(Comp
)
5481 or else (Is_Entity_Name
(Comp
)
5482 and then Present
(Entity
(Comp
))
5483 and then No
(Renamed_Object
(Entity
(Comp
))))
5485 or else (Nkind
(Comp
) = N_Attribute_Reference
5486 and then Check_Component
(Prefix
(Comp
)))
5488 or else (Nkind
(Comp
) in N_Binary_Op
5489 and then Check_Component
(Left_Opnd
(Comp
))
5490 and then Check_Component
(Right_Opnd
(Comp
)))
5492 or else (Nkind
(Comp
) in N_Unary_Op
5493 and then Check_Component
(Right_Opnd
(Comp
)))
5495 or else (Nkind
(Comp
) = N_Selected_Component
5496 and then Check_Component
(Prefix
(Comp
)))
5498 or else (Nkind
(Comp
) = N_Unchecked_Type_Conversion
5499 and then Check_Component
(Expression
(Comp
)));
5500 end Check_Component
;
5502 -- Start of processing for Safe_Component
5505 -- If the component appears in an association that may correspond
5506 -- to more than one element, it is not analyzed before expansion
5507 -- into assignments, to avoid side effects. We analyze, but do not
5508 -- resolve the copy, to obtain sufficient entity information for
5509 -- the checks that follow. If component is overloaded we assume
5510 -- an unsafe function call.
5512 if not Analyzed
(Comp
) then
5513 if Is_Overloaded
(Expr
) then
5516 elsif Nkind
(Expr
) = N_Aggregate
5517 and then not Is_Others_Aggregate
(Expr
)
5521 elsif Nkind
(Expr
) = N_Allocator
then
5523 -- For now, too complex to analyze
5527 elsif Nkind
(Parent
(Expr
)) =
5528 N_Iterated_Component_Association
5530 -- Ditto for iterated component associations, which in
5531 -- general require an enclosing loop and involve nonstatic
5537 Comp
:= New_Copy_Tree
(Expr
);
5538 Set_Parent
(Comp
, Parent
(Expr
));
5542 if Nkind
(Comp
) = N_Aggregate
then
5543 return Safe_Aggregate
(Comp
);
5545 return Check_Component
(Comp
);
5549 -- Start of processing for In_Place_Assign_OK
5552 if Present
(Component_Associations
(N
)) then
5554 -- On assignment, sliding can take place, so we cannot do the
5555 -- assignment in place unless the bounds of the aggregate are
5556 -- statically equal to those of the target.
5558 -- If the aggregate is given by an others choice, the bounds are
5559 -- derived from the left-hand side, and the assignment is safe if
5560 -- the expression is.
5562 if Is_Others_Aggregate
(N
) then
5565 (Expression
(First
(Component_Associations
(N
))));
5568 Aggr_In
:= First_Index
(Etype
(N
));
5570 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
5571 Obj_In
:= First_Index
(Etype
(Name
(Parent
(N
))));
5574 -- Context is an allocator. Check bounds of aggregate against
5575 -- given type in qualified expression.
5577 pragma Assert
(Nkind
(Parent
(Parent
(N
))) = N_Allocator
);
5579 First_Index
(Etype
(Entity
(Subtype_Mark
(Parent
(N
)))));
5582 while Present
(Aggr_In
) loop
5583 Get_Index_Bounds
(Aggr_In
, Aggr_Lo
, Aggr_Hi
);
5584 Get_Index_Bounds
(Obj_In
, Obj_Lo
, Obj_Hi
);
5586 if not Compile_Time_Known_Value
(Aggr_Lo
)
5587 or else not Compile_Time_Known_Value
(Obj_Lo
)
5588 or else not Compile_Time_Known_Value
(Obj_Hi
)
5589 or else Expr_Value
(Aggr_Lo
) /= Expr_Value
(Obj_Lo
)
5593 -- For an assignment statement we require static matching of
5594 -- bounds. Ditto for an allocator whose qualified expression
5595 -- is a constrained type. If the expression in the allocator
5596 -- is an unconstrained array, we accept an upper bound that
5597 -- is not static, to allow for nonstatic expressions of the
5598 -- base type. Clearly there are further possibilities (with
5599 -- diminishing returns) for safely building arrays in place
5602 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
5603 or else Is_Constrained
(Etype
(Parent
(N
)))
5605 if not Compile_Time_Known_Value
(Aggr_Hi
)
5606 or else Expr_Value
(Aggr_Hi
) /= Expr_Value
(Obj_Hi
)
5612 Next_Index
(Aggr_In
);
5613 Next_Index
(Obj_In
);
5617 -- Now check the component values themselves
5619 return Safe_Aggregate
(N
);
5620 end In_Place_Assign_OK
;
5626 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
5627 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
5628 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
5629 -- The bounds of the aggregate for this dimension
5631 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
5632 -- The index type for this dimension
5634 Need_To_Check
: Boolean := False;
5636 Choices_Lo
: Node_Id
:= Empty
;
5637 Choices_Hi
: Node_Id
:= Empty
;
5638 -- The lowest and highest discrete choices for a named subaggregate
5640 Nb_Choices
: Int
:= -1;
5641 -- The number of discrete non-others choices in this subaggregate
5643 Nb_Elements
: Uint
:= Uint_0
;
5644 -- The number of elements in a positional aggregate
5646 Cond
: Node_Id
:= Empty
;
5653 -- Check if we have an others choice. If we do make sure that this
5654 -- subaggregate contains at least one element in addition to the
5657 if Range_Checks_Suppressed
(Ind_Typ
) then
5658 Need_To_Check
:= False;
5660 elsif Present
(Expressions
(Sub_Aggr
))
5661 and then Present
(Component_Associations
(Sub_Aggr
))
5663 Need_To_Check
:= True;
5665 elsif Present
(Component_Associations
(Sub_Aggr
)) then
5666 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
5668 if Nkind
(First
(Choice_List
(Assoc
))) /= N_Others_Choice
then
5669 Need_To_Check
:= False;
5672 -- Count the number of discrete choices. Start with -1 because
5673 -- the others choice does not count.
5675 -- Is there some reason we do not use List_Length here ???
5678 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5679 while Present
(Assoc
) loop
5680 Choice
:= First
(Choice_List
(Assoc
));
5681 while Present
(Choice
) loop
5682 Nb_Choices
:= Nb_Choices
+ 1;
5689 -- If there is only an others choice nothing to do
5691 Need_To_Check
:= (Nb_Choices
> 0);
5695 Need_To_Check
:= False;
5698 -- If we are dealing with a positional subaggregate with an others
5699 -- choice then compute the number or positional elements.
5701 if Need_To_Check
and then Present
(Expressions
(Sub_Aggr
)) then
5702 Expr
:= First
(Expressions
(Sub_Aggr
));
5703 Nb_Elements
:= Uint_0
;
5704 while Present
(Expr
) loop
5705 Nb_Elements
:= Nb_Elements
+ 1;
5709 -- If the aggregate contains discrete choices and an others choice
5710 -- compute the smallest and largest discrete choice values.
5712 elsif Need_To_Check
then
5713 Compute_Choices_Lo_And_Choices_Hi
: declare
5715 Table
: Case_Table_Type
(1 .. Nb_Choices
);
5716 -- Used to sort all the different choice values
5723 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5724 while Present
(Assoc
) loop
5725 Choice
:= First
(Choice_List
(Assoc
));
5726 while Present
(Choice
) loop
5727 if Nkind
(Choice
) = N_Others_Choice
then
5731 Get_Index_Bounds
(Choice
, Low
, High
);
5732 Table
(J
).Choice_Lo
:= Low
;
5733 Table
(J
).Choice_Hi
:= High
;
5742 -- Sort the discrete choices
5744 Sort_Case_Table
(Table
);
5746 Choices_Lo
:= Table
(1).Choice_Lo
;
5747 Choices_Hi
:= Table
(Nb_Choices
).Choice_Hi
;
5748 end Compute_Choices_Lo_And_Choices_Hi
;
5751 -- If no others choice in this subaggregate, or the aggregate
5752 -- comprises only an others choice, nothing to do.
5754 if not Need_To_Check
then
5757 -- If we are dealing with an aggregate containing an others choice
5758 -- and positional components, we generate the following test:
5760 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
5761 -- Ind_Typ'Pos (Aggr_Hi)
5763 -- raise Constraint_Error;
5766 elsif Nb_Elements
> Uint_0
then
5772 Make_Attribute_Reference
(Loc
,
5773 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
5774 Attribute_Name
=> Name_Pos
,
5777 (Duplicate_Subexpr_Move_Checks
(Aggr_Lo
))),
5778 Right_Opnd
=> Make_Integer_Literal
(Loc
, Nb_Elements
- 1)),
5781 Make_Attribute_Reference
(Loc
,
5782 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
5783 Attribute_Name
=> Name_Pos
,
5784 Expressions
=> New_List
(
5785 Duplicate_Subexpr_Move_Checks
(Aggr_Hi
))));
5787 -- If we are dealing with an aggregate containing an others choice
5788 -- and discrete choices we generate the following test:
5790 -- [constraint_error when
5791 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
5798 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Choices_Lo
),
5799 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
)),
5803 Left_Opnd
=> Duplicate_Subexpr
(Choices_Hi
),
5804 Right_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
)));
5807 if Present
(Cond
) then
5809 Make_Raise_Constraint_Error
(Loc
,
5811 Reason
=> CE_Length_Check_Failed
));
5812 -- Questionable reason code, shouldn't that be a
5813 -- CE_Range_Check_Failed ???
5816 -- Now look inside the subaggregate to see if there is more work
5818 if Dim
< Aggr_Dimension
then
5820 -- Process positional components
5822 if Present
(Expressions
(Sub_Aggr
)) then
5823 Expr
:= First
(Expressions
(Sub_Aggr
));
5824 while Present
(Expr
) loop
5825 Others_Check
(Expr
, Dim
+ 1);
5830 -- Process component associations
5832 if Present
(Component_Associations
(Sub_Aggr
)) then
5833 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5834 while Present
(Assoc
) loop
5835 Expr
:= Expression
(Assoc
);
5836 Others_Check
(Expr
, Dim
+ 1);
5843 -------------------------
5844 -- Safe_Left_Hand_Side --
5845 -------------------------
5847 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean is
5848 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean;
5849 -- If the left-hand side includes an indexed component, check that
5850 -- the indexes are free of side effects.
5856 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean is
5858 if Is_Entity_Name
(Indx
) then
5861 elsif Nkind
(Indx
) = N_Integer_Literal
then
5864 elsif Nkind
(Indx
) = N_Function_Call
5865 and then Is_Entity_Name
(Name
(Indx
))
5866 and then Has_Pragma_Pure_Function
(Entity
(Name
(Indx
)))
5870 elsif Nkind
(Indx
) = N_Type_Conversion
5871 and then Is_Safe_Index
(Expression
(Indx
))
5880 -- Start of processing for Safe_Left_Hand_Side
5883 if Is_Entity_Name
(N
) then
5886 elsif Nkind_In
(N
, N_Explicit_Dereference
, N_Selected_Component
)
5887 and then Safe_Left_Hand_Side
(Prefix
(N
))
5891 elsif Nkind
(N
) = N_Indexed_Component
5892 and then Safe_Left_Hand_Side
(Prefix
(N
))
5893 and then Is_Safe_Index
(First
(Expressions
(N
)))
5897 elsif Nkind
(N
) = N_Unchecked_Type_Conversion
then
5898 return Safe_Left_Hand_Side
(Expression
(N
));
5903 end Safe_Left_Hand_Side
;
5908 -- Holds the temporary aggregate value
5911 -- Holds the declaration of Tmp
5913 Aggr_Code
: List_Id
;
5914 Parent_Node
: Node_Id
;
5915 Parent_Kind
: Node_Kind
;
5917 -- Start of processing for Expand_Array_Aggregate
5920 -- Do not touch the special aggregates of attributes used for Asm calls
5922 if Is_RTE
(Ctyp
, RE_Asm_Input_Operand
)
5923 or else Is_RTE
(Ctyp
, RE_Asm_Output_Operand
)
5927 -- Do not expand an aggregate for an array type which contains tasks if
5928 -- the aggregate is associated with an unexpanded return statement of a
5929 -- build-in-place function. The aggregate is expanded when the related
5930 -- return statement (rewritten into an extended return) is processed.
5931 -- This delay ensures that any temporaries and initialization code
5932 -- generated for the aggregate appear in the proper return block and
5933 -- use the correct _chain and _master.
5935 elsif Has_Task
(Base_Type
(Etype
(N
)))
5936 and then Nkind
(Parent
(N
)) = N_Simple_Return_Statement
5937 and then Is_Build_In_Place_Function
5938 (Return_Applies_To
(Return_Statement_Entity
(Parent
(N
))))
5942 -- Do not attempt expansion if error already detected. We may reach this
5943 -- point in spite of previous errors when compiling with -gnatq, to
5944 -- force all possible errors (this is the usual ACATS mode).
5946 elsif Error_Posted
(N
) then
5950 -- If the semantic analyzer has determined that aggregate N will raise
5951 -- Constraint_Error at run time, then the aggregate node has been
5952 -- replaced with an N_Raise_Constraint_Error node and we should
5955 pragma Assert
(not Raises_Constraint_Error
(N
));
5959 -- Check that the index range defined by aggregate bounds is
5960 -- compatible with corresponding index subtype.
5962 Index_Compatibility_Check
: declare
5963 Aggr_Index_Range
: Node_Id
:= First_Index
(Typ
);
5964 -- The current aggregate index range
5966 Index_Constraint
: Node_Id
:= First_Index
(Etype
(Typ
));
5967 -- The corresponding index constraint against which we have to
5968 -- check the above aggregate index range.
5971 Compute_Others_Present
(N
, 1);
5973 for J
in 1 .. Aggr_Dimension
loop
5974 -- There is no need to emit a check if an others choice is present
5975 -- for this array aggregate dimension since in this case one of
5976 -- N's subaggregates has taken its bounds from the context and
5977 -- these bounds must have been checked already. In addition all
5978 -- subaggregates corresponding to the same dimension must all have
5979 -- the same bounds (checked in (c) below).
5981 if not Range_Checks_Suppressed
(Etype
(Index_Constraint
))
5982 and then not Others_Present
(J
)
5984 -- We don't use Checks.Apply_Range_Check here because it emits
5985 -- a spurious check. Namely it checks that the range defined by
5986 -- the aggregate bounds is nonempty. But we know this already
5989 Check_Bounds
(Aggr_Index_Range
, Index_Constraint
);
5992 -- Save the low and high bounds of the aggregate index as well as
5993 -- the index type for later use in checks (b) and (c) below.
5995 Aggr_Low
(J
) := Low_Bound
(Aggr_Index_Range
);
5996 Aggr_High
(J
) := High_Bound
(Aggr_Index_Range
);
5998 Aggr_Index_Typ
(J
) := Etype
(Index_Constraint
);
6000 Next_Index
(Aggr_Index_Range
);
6001 Next_Index
(Index_Constraint
);
6003 end Index_Compatibility_Check
;
6007 -- If an others choice is present check that no aggregate index is
6008 -- outside the bounds of the index constraint.
6010 Others_Check
(N
, 1);
6014 -- For multidimensional arrays make sure that all subaggregates
6015 -- corresponding to the same dimension have the same bounds.
6017 if Aggr_Dimension
> 1 then
6018 Check_Same_Aggr_Bounds
(N
, 1);
6023 -- If we have a default component value, or simple initialization is
6024 -- required for the component type, then we replace <> in component
6025 -- associations by the required default value.
6028 Default_Val
: Node_Id
;
6032 if (Present
(Default_Aspect_Component_Value
(Typ
))
6033 or else Needs_Simple_Initialization
(Ctyp
))
6034 and then Present
(Component_Associations
(N
))
6036 Assoc
:= First
(Component_Associations
(N
));
6037 while Present
(Assoc
) loop
6038 if Nkind
(Assoc
) = N_Component_Association
6039 and then Box_Present
(Assoc
)
6041 Set_Box_Present
(Assoc
, False);
6043 if Present
(Default_Aspect_Component_Value
(Typ
)) then
6044 Default_Val
:= Default_Aspect_Component_Value
(Typ
);
6046 Default_Val
:= Get_Simple_Init_Val
(Ctyp
, N
);
6049 Set_Expression
(Assoc
, New_Copy_Tree
(Default_Val
));
6050 Analyze_And_Resolve
(Expression
(Assoc
), Ctyp
);
6060 -- Here we test for is packed array aggregate that we can handle at
6061 -- compile time. If so, return with transformation done. Note that we do
6062 -- this even if the aggregate is nested, because once we have done this
6063 -- processing, there is no more nested aggregate.
6065 if Packed_Array_Aggregate_Handled
(N
) then
6069 -- At this point we try to convert to positional form
6071 if Ekind
(Current_Scope
) = E_Package
6072 and then Static_Elaboration_Desired
(Current_Scope
)
6074 Convert_To_Positional
(N
, Max_Others_Replicate
=> 100);
6076 Convert_To_Positional
(N
);
6079 -- if the result is no longer an aggregate (e.g. it may be a string
6080 -- literal, or a temporary which has the needed value), then we are
6081 -- done, since there is no longer a nested aggregate.
6083 if Nkind
(N
) /= N_Aggregate
then
6086 -- We are also done if the result is an analyzed aggregate, indicating
6087 -- that Convert_To_Positional succeeded and reanalyzed the rewritten
6090 elsif Analyzed
(N
) and then N
/= Original_Node
(N
) then
6094 -- If all aggregate components are compile-time known and the aggregate
6095 -- has been flattened, nothing left to do. The same occurs if the
6096 -- aggregate is used to initialize the components of a statically
6097 -- allocated dispatch table.
6099 if Compile_Time_Known_Aggregate
(N
)
6100 or else Is_Static_Dispatch_Table_Aggregate
(N
)
6102 Set_Expansion_Delayed
(N
, False);
6106 -- Now see if back end processing is possible
6108 if Backend_Processing_Possible
(N
) then
6110 -- If the aggregate is static but the constraints are not, build
6111 -- a static subtype for the aggregate, so that Gigi can place it
6112 -- in static memory. Perform an unchecked_conversion to the non-
6113 -- static type imposed by the context.
6116 Itype
: constant Entity_Id
:= Etype
(N
);
6118 Needs_Type
: Boolean := False;
6121 Index
:= First_Index
(Itype
);
6122 while Present
(Index
) loop
6123 if not Is_OK_Static_Subtype
(Etype
(Index
)) then
6132 Build_Constrained_Type
(Positional
=> True);
6133 Rewrite
(N
, Unchecked_Convert_To
(Itype
, N
));
6143 -- Delay expansion for nested aggregates: it will be taken care of when
6144 -- the parent aggregate is expanded.
6146 Parent_Node
:= Parent
(N
);
6147 Parent_Kind
:= Nkind
(Parent_Node
);
6149 if Parent_Kind
= N_Qualified_Expression
then
6150 Parent_Node
:= Parent
(Parent_Node
);
6151 Parent_Kind
:= Nkind
(Parent_Node
);
6154 if Parent_Kind
= N_Aggregate
6155 or else Parent_Kind
= N_Extension_Aggregate
6156 or else Parent_Kind
= N_Component_Association
6157 or else (Parent_Kind
= N_Object_Declaration
6158 and then Needs_Finalization
(Typ
))
6159 or else (Parent_Kind
= N_Assignment_Statement
6160 and then Inside_Init_Proc
)
6162 if Static_Array_Aggregate
(N
)
6163 or else Compile_Time_Known_Aggregate
(N
)
6165 Set_Expansion_Delayed
(N
, False);
6168 Set_Expansion_Delayed
(N
);
6175 -- Look if in place aggregate expansion is possible
6177 -- For object declarations we build the aggregate in place, unless
6178 -- the array is bit-packed or the component is controlled.
6180 -- For assignments we do the assignment in place if all the component
6181 -- associations have compile-time known values. For other cases we
6182 -- create a temporary. The analysis for safety of on-line assignment
6183 -- is delicate, i.e. we don't know how to do it fully yet ???
6185 -- For allocators we assign to the designated object in place if the
6186 -- aggregate meets the same conditions as other in-place assignments.
6187 -- In this case the aggregate may not come from source but was created
6188 -- for default initialization, e.g. with Initialize_Scalars.
6190 if Requires_Transient_Scope
(Typ
) then
6191 Establish_Transient_Scope
(N
, Manage_Sec_Stack
=> False);
6194 if Has_Default_Init_Comps
(N
) then
6195 Maybe_In_Place_OK
:= False;
6197 elsif Is_Bit_Packed_Array
(Typ
)
6198 or else Has_Controlled_Component
(Typ
)
6200 Maybe_In_Place_OK
:= False;
6203 Maybe_In_Place_OK
:=
6204 (Nkind
(Parent
(N
)) = N_Assignment_Statement
6205 and then In_Place_Assign_OK
)
6208 (Nkind
(Parent
(Parent
(N
))) = N_Allocator
6209 and then In_Place_Assign_OK
);
6212 -- If this is an array of tasks, it will be expanded into build-in-place
6213 -- assignments. Build an activation chain for the tasks now.
6215 if Has_Task
(Etype
(N
)) then
6216 Build_Activation_Chain_Entity
(N
);
6219 -- Perform in-place expansion of aggregate in an object declaration.
6220 -- Note: actions generated for the aggregate will be captured in an
6221 -- expression-with-actions statement so that they can be transferred
6222 -- to freeze actions later if there is an address clause for the
6223 -- object. (Note: we don't use a block statement because this would
6224 -- cause generated freeze nodes to be elaborated in the wrong scope).
6226 -- Do not perform in-place expansion for SPARK 05 because aggregates are
6227 -- expected to appear in qualified form. In-place expansion eliminates
6228 -- the qualification and eventually violates this SPARK 05 restiction.
6230 -- Should document the rest of the guards ???
6232 if not Has_Default_Init_Comps
(N
)
6233 and then Comes_From_Source
(Parent_Node
)
6234 and then Parent_Kind
= N_Object_Declaration
6235 and then Present
(Expression
(Parent_Node
))
6237 Must_Slide
(Etype
(Defining_Identifier
(Parent_Node
)), Typ
)
6238 and then not Has_Controlled_Component
(Typ
)
6239 and then not Is_Bit_Packed_Array
(Typ
)
6240 and then not Restriction_Check_Required
(SPARK_05
)
6242 In_Place_Assign_OK_For_Declaration
:= True;
6243 Tmp
:= Defining_Identifier
(Parent_Node
);
6244 Set_No_Initialization
(Parent_Node
);
6245 Set_Expression
(Parent_Node
, Empty
);
6247 -- Set kind and type of the entity, for use in the analysis
6248 -- of the subsequent assignments. If the nominal type is not
6249 -- constrained, build a subtype from the known bounds of the
6250 -- aggregate. If the declaration has a subtype mark, use it,
6251 -- otherwise use the itype of the aggregate.
6253 Set_Ekind
(Tmp
, E_Variable
);
6255 if not Is_Constrained
(Typ
) then
6256 Build_Constrained_Type
(Positional
=> False);
6258 elsif Is_Entity_Name
(Object_Definition
(Parent_Node
))
6259 and then Is_Constrained
(Entity
(Object_Definition
(Parent_Node
)))
6261 Set_Etype
(Tmp
, Entity
(Object_Definition
(Parent_Node
)));
6264 Set_Size_Known_At_Compile_Time
(Typ
, False);
6265 Set_Etype
(Tmp
, Typ
);
6268 elsif Maybe_In_Place_OK
6269 and then Nkind
(Parent
(N
)) = N_Qualified_Expression
6270 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
6272 Set_Expansion_Delayed
(N
);
6275 -- In the remaining cases the aggregate is the RHS of an assignment
6277 elsif Maybe_In_Place_OK
6278 and then Safe_Left_Hand_Side
(Name
(Parent
(N
)))
6280 Tmp
:= Name
(Parent
(N
));
6282 if Etype
(Tmp
) /= Etype
(N
) then
6283 Apply_Length_Check
(N
, Etype
(Tmp
));
6285 if Nkind
(N
) = N_Raise_Constraint_Error
then
6287 -- Static error, nothing further to expand
6293 -- If a slice assignment has an aggregate with a single others_choice,
6294 -- the assignment can be done in place even if bounds are not static,
6295 -- by converting it into a loop over the discrete range of the slice.
6297 elsif Maybe_In_Place_OK
6298 and then Nkind
(Name
(Parent
(N
))) = N_Slice
6299 and then Is_Others_Aggregate
(N
)
6301 Tmp
:= Name
(Parent
(N
));
6303 -- Set type of aggregate to be type of lhs in assignment, in order
6304 -- to suppress redundant length checks.
6306 Set_Etype
(N
, Etype
(Tmp
));
6310 -- In place aggregate expansion is not possible
6313 Maybe_In_Place_OK
:= False;
6314 Tmp
:= Make_Temporary
(Loc
, 'A', N
);
6316 Make_Object_Declaration
(Loc
,
6317 Defining_Identifier
=> Tmp
,
6318 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
6319 Set_No_Initialization
(Tmp_Decl
, True);
6321 -- If we are within a loop, the temporary will be pushed on the
6322 -- stack at each iteration. If the aggregate is the expression
6323 -- for an allocator, it will be immediately copied to the heap
6324 -- and can be reclaimed at once. We create a transient scope
6325 -- around the aggregate for this purpose.
6327 if Ekind
(Current_Scope
) = E_Loop
6328 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
6330 Establish_Transient_Scope
(N
, Manage_Sec_Stack
=> False);
6333 Insert_Action
(N
, Tmp_Decl
);
6336 -- Construct and insert the aggregate code. We can safely suppress index
6337 -- checks because this code is guaranteed not to raise CE on index
6338 -- checks. However we should *not* suppress all checks.
6344 if Nkind
(Tmp
) = N_Defining_Identifier
then
6345 Target
:= New_Occurrence_Of
(Tmp
, Loc
);
6348 if Has_Default_Init_Comps
(N
) then
6350 -- Ada 2005 (AI-287): This case has not been analyzed???
6352 raise Program_Error
;
6355 -- Name in assignment is explicit dereference
6357 Target
:= New_Copy
(Tmp
);
6360 -- If we are to generate an in place assignment for a declaration or
6361 -- an assignment statement, and the assignment can be done directly
6362 -- by the back end, then do not expand further.
6364 -- ??? We can also do that if in place expansion is not possible but
6365 -- then we could go into an infinite recursion.
6367 if (In_Place_Assign_OK_For_Declaration
or else Maybe_In_Place_OK
)
6368 and then not CodePeer_Mode
6369 and then not Modify_Tree_For_C
6370 and then not Possible_Bit_Aligned_Component
(Target
)
6371 and then not Is_Possibly_Unaligned_Slice
(Target
)
6372 and then Aggr_Assignment_OK_For_Backend
(N
)
6374 if Maybe_In_Place_OK
then
6380 Make_Assignment_Statement
(Loc
,
6382 Expression
=> New_Copy_Tree
(N
)));
6386 Build_Array_Aggr_Code
(N
,
6388 Index
=> First_Index
(Typ
),
6390 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
6393 -- Save the last assignment statement associated with the aggregate
6394 -- when building a controlled object. This reference is utilized by
6395 -- the finalization machinery when marking an object as successfully
6398 if Needs_Finalization
(Typ
)
6399 and then Is_Entity_Name
(Target
)
6400 and then Present
(Entity
(Target
))
6401 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
6403 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
6407 -- If the aggregate is the expression in a declaration, the expanded
6408 -- code must be inserted after it. The defining entity might not come
6409 -- from source if this is part of an inlined body, but the declaration
6412 if Comes_From_Source
(Tmp
)
6414 (Nkind
(Parent
(N
)) = N_Object_Declaration
6415 and then Comes_From_Source
(Parent
(N
))
6416 and then Tmp
= Defining_Entity
(Parent
(N
)))
6419 Node_After
: constant Node_Id
:= Next
(Parent_Node
);
6422 Insert_Actions_After
(Parent_Node
, Aggr_Code
);
6424 if Parent_Kind
= N_Object_Declaration
then
6425 Collect_Initialization_Statements
6426 (Obj
=> Tmp
, N
=> Parent_Node
, Node_After
=> Node_After
);
6431 Insert_Actions
(N
, Aggr_Code
);
6434 -- If the aggregate has been assigned in place, remove the original
6437 if Nkind
(Parent
(N
)) = N_Assignment_Statement
6438 and then Maybe_In_Place_OK
6440 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
6442 elsif Nkind
(Parent
(N
)) /= N_Object_Declaration
6443 or else Tmp
/= Defining_Identifier
(Parent
(N
))
6445 Rewrite
(N
, New_Occurrence_Of
(Tmp
, Loc
));
6446 Analyze_And_Resolve
(N
, Typ
);
6448 end Expand_Array_Aggregate
;
6450 ------------------------
6451 -- Expand_N_Aggregate --
6452 ------------------------
6454 procedure Expand_N_Aggregate
(N
: Node_Id
) is
6456 -- Record aggregate case
6458 if Is_Record_Type
(Etype
(N
)) then
6459 Expand_Record_Aggregate
(N
);
6461 -- Array aggregate case
6464 -- A special case, if we have a string subtype with bounds 1 .. N,
6465 -- where N is known at compile time, and the aggregate is of the
6466 -- form (others => 'x'), with a single choice and no expressions,
6467 -- and N is less than 80 (an arbitrary limit for now), then replace
6468 -- the aggregate by the equivalent string literal (but do not mark
6469 -- it as static since it is not).
6471 -- Note: this entire circuit is redundant with respect to code in
6472 -- Expand_Array_Aggregate that collapses others choices to positional
6473 -- form, but there are two problems with that circuit:
6475 -- a) It is limited to very small cases due to ill-understood
6476 -- interactions with bootstrapping. That limit is removed by
6477 -- use of the No_Implicit_Loops restriction.
6479 -- b) It incorrectly ends up with the resulting expressions being
6480 -- considered static when they are not. For example, the
6481 -- following test should fail:
6483 -- pragma Restrictions (No_Implicit_Loops);
6484 -- package NonSOthers4 is
6485 -- B : constant String (1 .. 6) := (others => 'A');
6486 -- DH : constant String (1 .. 8) := B & "BB";
6488 -- pragma Export (C, X, Link_Name => DH);
6491 -- But it succeeds (DH looks static to pragma Export)
6493 -- To be sorted out ???
6495 if Present
(Component_Associations
(N
)) then
6497 CA
: constant Node_Id
:= First
(Component_Associations
(N
));
6498 MX
: constant := 80;
6501 if Nkind
(First
(Choice_List
(CA
))) = N_Others_Choice
6502 and then Nkind
(Expression
(CA
)) = N_Character_Literal
6503 and then No
(Expressions
(N
))
6506 T
: constant Entity_Id
:= Etype
(N
);
6507 X
: constant Node_Id
:= First_Index
(T
);
6508 EC
: constant Node_Id
:= Expression
(CA
);
6509 CV
: constant Uint
:= Char_Literal_Value
(EC
);
6510 CC
: constant Int
:= UI_To_Int
(CV
);
6513 if Nkind
(X
) = N_Range
6514 and then Compile_Time_Known_Value
(Low_Bound
(X
))
6515 and then Expr_Value
(Low_Bound
(X
)) = 1
6516 and then Compile_Time_Known_Value
(High_Bound
(X
))
6519 Hi
: constant Uint
:= Expr_Value
(High_Bound
(X
));
6525 for J
in 1 .. UI_To_Int
(Hi
) loop
6526 Store_String_Char
(Char_Code
(CC
));
6530 Make_String_Literal
(Sloc
(N
),
6531 Strval
=> End_String
));
6533 if CC
>= Int
(2 ** 16) then
6534 Set_Has_Wide_Wide_Character
(N
);
6535 elsif CC
>= Int
(2 ** 8) then
6536 Set_Has_Wide_Character
(N
);
6539 Analyze_And_Resolve
(N
, T
);
6540 Set_Is_Static_Expression
(N
, False);
6550 -- Not that special case, so normal expansion of array aggregate
6552 Expand_Array_Aggregate
(N
);
6556 when RE_Not_Available
=>
6558 end Expand_N_Aggregate
;
6560 ------------------------------
6561 -- Expand_N_Delta_Aggregate --
6562 ------------------------------
6564 procedure Expand_N_Delta_Aggregate
(N
: Node_Id
) is
6565 Loc
: constant Source_Ptr
:= Sloc
(N
);
6566 Typ
: constant Entity_Id
:= Etype
(N
);
6571 Make_Object_Declaration
(Loc
,
6572 Defining_Identifier
=> Make_Temporary
(Loc
, 'T'),
6573 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
),
6574 Expression
=> New_Copy_Tree
(Expression
(N
)));
6576 if Is_Array_Type
(Etype
(N
)) then
6577 Expand_Delta_Array_Aggregate
(N
, New_List
(Decl
));
6579 Expand_Delta_Record_Aggregate
(N
, New_List
(Decl
));
6581 end Expand_N_Delta_Aggregate
;
6583 ----------------------------------
6584 -- Expand_Delta_Array_Aggregate --
6585 ----------------------------------
6587 procedure Expand_Delta_Array_Aggregate
(N
: Node_Id
; Deltas
: List_Id
) is
6588 Loc
: constant Source_Ptr
:= Sloc
(N
);
6589 Temp
: constant Entity_Id
:= Defining_Identifier
(First
(Deltas
));
6592 function Generate_Loop
(C
: Node_Id
) return Node_Id
;
6593 -- Generate a loop containing individual component assignments for
6594 -- choices that are ranges, subtype indications, subtype names, and
6595 -- iterated component associations.
6601 function Generate_Loop
(C
: Node_Id
) return Node_Id
is
6602 Sl
: constant Source_Ptr
:= Sloc
(C
);
6606 if Nkind
(Parent
(C
)) = N_Iterated_Component_Association
then
6608 Make_Defining_Identifier
(Loc
,
6609 Chars
=> (Chars
(Defining_Identifier
(Parent
(C
)))));
6611 Ix
:= Make_Temporary
(Sl
, 'I');
6615 Make_Loop_Statement
(Loc
,
6617 Make_Iteration_Scheme
(Sl
,
6618 Loop_Parameter_Specification
=>
6619 Make_Loop_Parameter_Specification
(Sl
,
6620 Defining_Identifier
=> Ix
,
6621 Discrete_Subtype_Definition
=> New_Copy_Tree
(C
))),
6623 Statements
=> New_List
(
6624 Make_Assignment_Statement
(Sl
,
6626 Make_Indexed_Component
(Sl
,
6627 Prefix
=> New_Occurrence_Of
(Temp
, Sl
),
6628 Expressions
=> New_List
(New_Occurrence_Of
(Ix
, Sl
))),
6629 Expression
=> New_Copy_Tree
(Expression
(Assoc
)))),
6630 End_Label
=> Empty
);
6637 -- Start of processing for Expand_Delta_Array_Aggregate
6640 Assoc
:= First
(Component_Associations
(N
));
6641 while Present
(Assoc
) loop
6642 Choice
:= First
(Choice_List
(Assoc
));
6643 if Nkind
(Assoc
) = N_Iterated_Component_Association
then
6644 while Present
(Choice
) loop
6645 Append_To
(Deltas
, Generate_Loop
(Choice
));
6650 while Present
(Choice
) loop
6652 -- Choice can be given by a range, a subtype indication, a
6653 -- subtype name, a scalar value, or an entity.
6655 if Nkind
(Choice
) = N_Range
6656 or else (Is_Entity_Name
(Choice
)
6657 and then Is_Type
(Entity
(Choice
)))
6659 Append_To
(Deltas
, Generate_Loop
(Choice
));
6661 elsif Nkind
(Choice
) = N_Subtype_Indication
then
6663 Generate_Loop
(Range_Expression
(Constraint
(Choice
))));
6667 Make_Assignment_Statement
(Sloc
(Choice
),
6669 Make_Indexed_Component
(Sloc
(Choice
),
6670 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
6671 Expressions
=> New_List
(New_Copy_Tree
(Choice
))),
6672 Expression
=> New_Copy_Tree
(Expression
(Assoc
))));
6682 Insert_Actions
(N
, Deltas
);
6683 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
6684 end Expand_Delta_Array_Aggregate
;
6686 -----------------------------------
6687 -- Expand_Delta_Record_Aggregate --
6688 -----------------------------------
6690 procedure Expand_Delta_Record_Aggregate
(N
: Node_Id
; Deltas
: List_Id
) is
6691 Loc
: constant Source_Ptr
:= Sloc
(N
);
6692 Temp
: constant Entity_Id
:= Defining_Identifier
(First
(Deltas
));
6697 Assoc
:= First
(Component_Associations
(N
));
6699 while Present
(Assoc
) loop
6700 Choice
:= First
(Choice_List
(Assoc
));
6701 while Present
(Choice
) loop
6703 Make_Assignment_Statement
(Sloc
(Choice
),
6705 Make_Selected_Component
(Sloc
(Choice
),
6706 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
6707 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Choice
))),
6708 Expression
=> New_Copy_Tree
(Expression
(Assoc
))));
6715 Insert_Actions
(N
, Deltas
);
6716 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
6717 end Expand_Delta_Record_Aggregate
;
6719 ----------------------------------
6720 -- Expand_N_Extension_Aggregate --
6721 ----------------------------------
6723 -- If the ancestor part is an expression, add a component association for
6724 -- the parent field. If the type of the ancestor part is not the direct
6725 -- parent of the expected type, build recursively the needed ancestors.
6726 -- If the ancestor part is a subtype_mark, replace aggregate with a
6727 -- declaration for a temporary of the expected type, followed by
6728 -- individual assignments to the given components.
6730 procedure Expand_N_Extension_Aggregate
(N
: Node_Id
) is
6731 A
: constant Node_Id
:= Ancestor_Part
(N
);
6732 Loc
: constant Source_Ptr
:= Sloc
(N
);
6733 Typ
: constant Entity_Id
:= Etype
(N
);
6736 -- If the ancestor is a subtype mark, an init proc must be called
6737 -- on the resulting object which thus has to be materialized in
6740 if Is_Entity_Name
(A
) and then Is_Type
(Entity
(A
)) then
6741 Convert_To_Assignments
(N
, Typ
);
6743 -- The extension aggregate is transformed into a record aggregate
6744 -- of the following form (c1 and c2 are inherited components)
6746 -- (Exp with c3 => a, c4 => b)
6747 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c3 => a, c4 => b)
6752 if Tagged_Type_Expansion
then
6753 Expand_Record_Aggregate
(N
,
6756 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
),
6759 -- No tag is needed in the case of a VM
6762 Expand_Record_Aggregate
(N
, Parent_Expr
=> A
);
6767 when RE_Not_Available
=>
6769 end Expand_N_Extension_Aggregate
;
6771 -----------------------------
6772 -- Expand_Record_Aggregate --
6773 -----------------------------
6775 procedure Expand_Record_Aggregate
6777 Orig_Tag
: Node_Id
:= Empty
;
6778 Parent_Expr
: Node_Id
:= Empty
)
6780 Loc
: constant Source_Ptr
:= Sloc
(N
);
6781 Comps
: constant List_Id
:= Component_Associations
(N
);
6782 Typ
: constant Entity_Id
:= Etype
(N
);
6783 Base_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
6785 Static_Components
: Boolean := True;
6786 -- Flag to indicate whether all components are compile-time known,
6787 -- and the aggregate can be constructed statically and handled by
6788 -- the back-end. Set to False by Component_OK_For_Backend.
6790 procedure Build_Back_End_Aggregate
;
6791 -- Build a proper aggregate to be handled by the back-end
6793 function Compile_Time_Known_Composite_Value
(N
: Node_Id
) return Boolean;
6794 -- Returns true if N is an expression of composite type which can be
6795 -- fully evaluated at compile time without raising constraint error.
6796 -- Such expressions can be passed as is to Gigi without any expansion.
6798 -- This returns true for N_Aggregate with Compile_Time_Known_Aggregate
6799 -- set and constants whose expression is such an aggregate, recursively.
6801 function Component_OK_For_Backend
return Boolean;
6802 -- Check for presence of a component which makes it impossible for the
6803 -- backend to process the aggregate, thus requiring the use of a series
6804 -- of assignment statements. Cases checked for are a nested aggregate
6805 -- needing Late_Expansion, the presence of a tagged component which may
6806 -- need tag adjustment, and a bit unaligned component reference.
6808 -- We also force expansion into assignments if a component is of a
6809 -- mutable type (including a private type with discriminants) because
6810 -- in that case the size of the component to be copied may be smaller
6811 -- than the side of the target, and there is no simple way for gigi
6812 -- to compute the size of the object to be copied.
6814 -- NOTE: This is part of the ongoing work to define precisely the
6815 -- interface between front-end and back-end handling of aggregates.
6816 -- In general it is desirable to pass aggregates as they are to gigi,
6817 -- in order to minimize elaboration code. This is one case where the
6818 -- semantics of Ada complicate the analysis and lead to anomalies in
6819 -- the gcc back-end if the aggregate is not expanded into assignments.
6821 -- NOTE: This sets the global Static_Components to False in most, but
6822 -- not all, cases when it returns False.
6824 function Has_Per_Object_Constraint
(L
: List_Id
) return Boolean;
6825 -- Return True if any element of L has Has_Per_Object_Constraint set.
6826 -- L should be the Choices component of an N_Component_Association.
6828 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean;
6829 -- If any ancestor of the current type is private, the aggregate
6830 -- cannot be built in place. We cannot rely on Has_Private_Ancestor,
6831 -- because it will not be set when type and its parent are in the
6832 -- same scope, and the parent component needs expansion.
6834 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
;
6835 -- For nested aggregates return the ultimate enclosing aggregate; for
6836 -- non-nested aggregates return N.
6838 ------------------------------
6839 -- Build_Back_End_Aggregate --
6840 ------------------------------
6842 procedure Build_Back_End_Aggregate
is
6845 Tag_Value
: Node_Id
;
6848 if Nkind
(N
) = N_Aggregate
then
6850 -- If the aggregate is static and can be handled by the back-end,
6851 -- nothing left to do.
6853 if Static_Components
then
6854 Set_Compile_Time_Known_Aggregate
(N
);
6855 Set_Expansion_Delayed
(N
, False);
6859 -- If no discriminants, nothing special to do
6861 if not Has_Discriminants
(Typ
) then
6864 -- Case of discriminants present
6866 elsif Is_Derived_Type
(Typ
) then
6868 -- For untagged types, non-stored discriminants are replaced with
6869 -- stored discriminants, which are the ones that gigi uses to
6870 -- describe the type and its components.
6872 Generate_Aggregate_For_Derived_Type
: declare
6873 procedure Prepend_Stored_Values
(T
: Entity_Id
);
6874 -- Scan the list of stored discriminants of the type, and add
6875 -- their values to the aggregate being built.
6877 ---------------------------
6878 -- Prepend_Stored_Values --
6879 ---------------------------
6881 procedure Prepend_Stored_Values
(T
: Entity_Id
) is
6883 First_Comp
: Node_Id
:= Empty
;
6886 Discr
:= First_Stored_Discriminant
(T
);
6887 while Present
(Discr
) loop
6889 Make_Component_Association
(Loc
,
6890 Choices
=> New_List
(
6891 New_Occurrence_Of
(Discr
, Loc
)),
6894 (Get_Discriminant_Value
6897 Discriminant_Constraint
(Typ
))));
6899 if No
(First_Comp
) then
6900 Prepend_To
(Component_Associations
(N
), New_Comp
);
6902 Insert_After
(First_Comp
, New_Comp
);
6905 First_Comp
:= New_Comp
;
6906 Next_Stored_Discriminant
(Discr
);
6908 end Prepend_Stored_Values
;
6912 Constraints
: constant List_Id
:= New_List
;
6916 Num_Disc
: Nat
:= 0;
6917 Num_Gird
: Nat
:= 0;
6919 -- Start of processing for Generate_Aggregate_For_Derived_Type
6922 -- Remove the associations for the discriminant of derived type
6925 First_Comp
: Node_Id
;
6928 First_Comp
:= First
(Component_Associations
(N
));
6929 while Present
(First_Comp
) loop
6933 if Ekind
(Entity
(First
(Choices
(Comp
)))) =
6937 Num_Disc
:= Num_Disc
+ 1;
6942 -- Insert stored discriminant associations in the correct
6943 -- order. If there are more stored discriminants than new
6944 -- discriminants, there is at least one new discriminant that
6945 -- constrains more than one of the stored discriminants. In
6946 -- this case we need to construct a proper subtype of the
6947 -- parent type, in order to supply values to all the
6948 -- components. Otherwise there is one-one correspondence
6949 -- between the constraints and the stored discriminants.
6951 Discr
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6952 while Present
(Discr
) loop
6953 Num_Gird
:= Num_Gird
+ 1;
6954 Next_Stored_Discriminant
(Discr
);
6957 -- Case of more stored discriminants than new discriminants
6959 if Num_Gird
> Num_Disc
then
6961 -- Create a proper subtype of the parent type, which is the
6962 -- proper implementation type for the aggregate, and convert
6963 -- it to the intended target type.
6965 Discr
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6966 while Present
(Discr
) loop
6969 (Get_Discriminant_Value
6972 Discriminant_Constraint
(Typ
)));
6974 Append
(New_Comp
, Constraints
);
6975 Next_Stored_Discriminant
(Discr
);
6979 Make_Subtype_Declaration
(Loc
,
6980 Defining_Identifier
=> Make_Temporary
(Loc
, 'T'),
6981 Subtype_Indication
=>
6982 Make_Subtype_Indication
(Loc
,
6984 New_Occurrence_Of
(Etype
(Base_Type
(Typ
)), Loc
),
6986 Make_Index_Or_Discriminant_Constraint
6987 (Loc
, Constraints
)));
6989 Insert_Action
(N
, Decl
);
6990 Prepend_Stored_Values
(Base_Type
(Typ
));
6992 Set_Etype
(N
, Defining_Identifier
(Decl
));
6995 Rewrite
(N
, Unchecked_Convert_To
(Typ
, N
));
6998 -- Case where we do not have fewer new discriminants than
6999 -- stored discriminants, so in this case we can simply use the
7000 -- stored discriminants of the subtype.
7003 Prepend_Stored_Values
(Typ
);
7005 end Generate_Aggregate_For_Derived_Type
;
7008 if Is_Tagged_Type
(Typ
) then
7010 -- In the tagged case, _parent and _tag component must be created
7012 -- Reset Null_Present unconditionally. Tagged records always have
7013 -- at least one field (the tag or the parent).
7015 Set_Null_Record_Present
(N
, False);
7017 -- When the current aggregate comes from the expansion of an
7018 -- extension aggregate, the parent expr is replaced by an
7019 -- aggregate formed by selected components of this expr.
7021 if Present
(Parent_Expr
) and then Is_Empty_List
(Comps
) then
7022 Comp
:= First_Component_Or_Discriminant
(Typ
);
7023 while Present
(Comp
) loop
7025 -- Skip all expander-generated components
7027 if not Comes_From_Source
(Original_Record_Component
(Comp
))
7033 Make_Selected_Component
(Loc
,
7035 Unchecked_Convert_To
(Typ
,
7036 Duplicate_Subexpr
(Parent_Expr
, True)),
7037 Selector_Name
=> New_Occurrence_Of
(Comp
, Loc
));
7040 Make_Component_Association
(Loc
,
7041 Choices
=> New_List
(
7042 New_Occurrence_Of
(Comp
, Loc
)),
7043 Expression
=> New_Comp
));
7045 Analyze_And_Resolve
(New_Comp
, Etype
(Comp
));
7048 Next_Component_Or_Discriminant
(Comp
);
7052 -- Compute the value for the Tag now, if the type is a root it
7053 -- will be included in the aggregate right away, otherwise it will
7054 -- be propagated to the parent aggregate.
7056 if Present
(Orig_Tag
) then
7057 Tag_Value
:= Orig_Tag
;
7059 elsif not Tagged_Type_Expansion
then
7065 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
);
7068 -- For a derived type, an aggregate for the parent is formed with
7069 -- all the inherited components.
7071 if Is_Derived_Type
(Typ
) then
7073 First_Comp
: Node_Id
;
7074 Parent_Comps
: List_Id
;
7075 Parent_Aggr
: Node_Id
;
7076 Parent_Name
: Node_Id
;
7079 -- Remove the inherited component association from the
7080 -- aggregate and store them in the parent aggregate
7082 First_Comp
:= First
(Component_Associations
(N
));
7083 Parent_Comps
:= New_List
;
7084 while Present
(First_Comp
)
7086 Scope
(Original_Record_Component
7087 (Entity
(First
(Choices
(First_Comp
))))) /=
7093 Append
(Comp
, Parent_Comps
);
7097 Make_Aggregate
(Loc
,
7098 Component_Associations
=> Parent_Comps
);
7099 Set_Etype
(Parent_Aggr
, Etype
(Base_Type
(Typ
)));
7101 -- Find the _parent component
7103 Comp
:= First_Component
(Typ
);
7104 while Chars
(Comp
) /= Name_uParent
loop
7105 Comp
:= Next_Component
(Comp
);
7108 Parent_Name
:= New_Occurrence_Of
(Comp
, Loc
);
7110 -- Insert the parent aggregate
7112 Prepend_To
(Component_Associations
(N
),
7113 Make_Component_Association
(Loc
,
7114 Choices
=> New_List
(Parent_Name
),
7115 Expression
=> Parent_Aggr
));
7117 -- Expand recursively the parent propagating the right Tag
7119 Expand_Record_Aggregate
7120 (Parent_Aggr
, Tag_Value
, Parent_Expr
);
7122 -- The ancestor part may be a nested aggregate that has
7123 -- delayed expansion: recheck now.
7125 if not Component_OK_For_Backend
then
7126 Convert_To_Assignments
(N
, Typ
);
7130 -- For a root type, the tag component is added (unless compiling
7131 -- for the VMs, where tags are implicit).
7133 elsif Tagged_Type_Expansion
then
7135 Tag_Name
: constant Node_Id
:=
7137 (First_Tag_Component
(Typ
), Loc
);
7138 Typ_Tag
: constant Entity_Id
:= RTE
(RE_Tag
);
7139 Conv_Node
: constant Node_Id
:=
7140 Unchecked_Convert_To
(Typ_Tag
, Tag_Value
);
7143 Set_Etype
(Conv_Node
, Typ_Tag
);
7144 Prepend_To
(Component_Associations
(N
),
7145 Make_Component_Association
(Loc
,
7146 Choices
=> New_List
(Tag_Name
),
7147 Expression
=> Conv_Node
));
7151 end Build_Back_End_Aggregate
;
7153 ----------------------------------------
7154 -- Compile_Time_Known_Composite_Value --
7155 ----------------------------------------
7157 function Compile_Time_Known_Composite_Value
7158 (N
: Node_Id
) return Boolean
7161 -- If we have an entity name, then see if it is the name of a
7162 -- constant and if so, test the corresponding constant value.
7164 if Is_Entity_Name
(N
) then
7166 E
: constant Entity_Id
:= Entity
(N
);
7169 if Ekind
(E
) /= E_Constant
then
7172 V
:= Constant_Value
(E
);
7174 and then Compile_Time_Known_Composite_Value
(V
);
7178 -- We have a value, see if it is compile time known
7181 if Nkind
(N
) = N_Aggregate
then
7182 return Compile_Time_Known_Aggregate
(N
);
7185 -- All other types of values are not known at compile time
7190 end Compile_Time_Known_Composite_Value
;
7192 ------------------------------
7193 -- Component_OK_For_Backend --
7194 ------------------------------
7196 function Component_OK_For_Backend
return Boolean is
7206 while Present
(C
) loop
7208 -- If the component has box initialization, expansion is needed
7209 -- and component is not ready for backend.
7211 if Box_Present
(C
) then
7215 if Nkind
(Expression
(C
)) = N_Qualified_Expression
then
7216 Expr_Q
:= Expression
(Expression
(C
));
7218 Expr_Q
:= Expression
(C
);
7221 -- Return False if the aggregate has any associations for tagged
7222 -- components that may require tag adjustment.
7224 -- These are cases where the source expression may have a tag that
7225 -- could differ from the component tag (e.g., can occur for type
7226 -- conversions and formal parameters). (Tag adjustment not needed
7227 -- if Tagged_Type_Expansion because object tags are implicit in
7230 if Is_Tagged_Type
(Etype
(Expr_Q
))
7231 and then (Nkind
(Expr_Q
) = N_Type_Conversion
7232 or else (Is_Entity_Name
(Expr_Q
)
7234 Ekind
(Entity
(Expr_Q
)) in Formal_Kind
))
7235 and then Tagged_Type_Expansion
7237 Static_Components
:= False;
7240 elsif Is_Delayed_Aggregate
(Expr_Q
) then
7241 Static_Components
:= False;
7244 elsif Nkind
(Expr_Q
) = N_Quantified_Expression
then
7245 Static_Components
:= False;
7248 elsif Possible_Bit_Aligned_Component
(Expr_Q
) then
7249 Static_Components
:= False;
7252 elsif Modify_Tree_For_C
7253 and then Nkind
(C
) = N_Component_Association
7254 and then Has_Per_Object_Constraint
(Choices
(C
))
7256 Static_Components
:= False;
7259 elsif Modify_Tree_For_C
7260 and then Nkind
(Expr_Q
) = N_Identifier
7261 and then Is_Array_Type
(Etype
(Expr_Q
))
7263 Static_Components
:= False;
7266 elsif Modify_Tree_For_C
7267 and then Nkind
(Expr_Q
) = N_Type_Conversion
7268 and then Is_Array_Type
(Etype
(Expr_Q
))
7270 Static_Components
:= False;
7274 if Is_Elementary_Type
(Etype
(Expr_Q
)) then
7275 if not Compile_Time_Known_Value
(Expr_Q
) then
7276 Static_Components
:= False;
7279 elsif not Compile_Time_Known_Composite_Value
(Expr_Q
) then
7280 Static_Components
:= False;
7282 if Is_Private_Type
(Etype
(Expr_Q
))
7283 and then Has_Discriminants
(Etype
(Expr_Q
))
7293 end Component_OK_For_Backend
;
7295 -------------------------------
7296 -- Has_Per_Object_Constraint --
7297 -------------------------------
7299 function Has_Per_Object_Constraint
(L
: List_Id
) return Boolean is
7300 N
: Node_Id
:= First
(L
);
7302 while Present
(N
) loop
7303 if Is_Entity_Name
(N
)
7304 and then Present
(Entity
(N
))
7305 and then Has_Per_Object_Constraint
(Entity
(N
))
7314 end Has_Per_Object_Constraint
;
7316 -----------------------------------
7317 -- Has_Visible_Private_Ancestor --
7318 -----------------------------------
7320 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean is
7321 R
: constant Entity_Id
:= Root_Type
(Id
);
7322 T1
: Entity_Id
:= Id
;
7326 if Is_Private_Type
(T1
) then
7336 end Has_Visible_Private_Ancestor
;
7338 -------------------------
7339 -- Top_Level_Aggregate --
7340 -------------------------
7342 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
is
7347 while Present
(Parent
(Aggr
))
7348 and then Nkind_In
(Parent
(Aggr
), N_Aggregate
,
7349 N_Component_Association
)
7351 Aggr
:= Parent
(Aggr
);
7355 end Top_Level_Aggregate
;
7359 Top_Level_Aggr
: constant Node_Id
:= Top_Level_Aggregate
(N
);
7361 -- Start of processing for Expand_Record_Aggregate
7364 -- If the aggregate is to be assigned to an atomic/VFA variable, we have
7365 -- to prevent a piecemeal assignment even if the aggregate is to be
7366 -- expanded. We create a temporary for the aggregate, and assign the
7367 -- temporary instead, so that the back end can generate an atomic move
7370 if Is_Atomic_VFA_Aggregate
(N
) then
7373 -- No special management required for aggregates used to initialize
7374 -- statically allocated dispatch tables
7376 elsif Is_Static_Dispatch_Table_Aggregate
(N
) then
7380 -- Ada 2005 (AI-318-2): We need to convert to assignments if components
7381 -- are build-in-place function calls. The assignments will each turn
7382 -- into a build-in-place function call. If components are all static,
7383 -- we can pass the aggregate to the back end regardless of limitedness.
7385 -- Extension aggregates, aggregates in extended return statements, and
7386 -- aggregates for C++ imported types must be expanded.
7388 if Ada_Version
>= Ada_2005
and then Is_Limited_View
(Typ
) then
7389 if not Nkind_In
(Parent
(N
), N_Component_Association
,
7390 N_Object_Declaration
)
7392 Convert_To_Assignments
(N
, Typ
);
7394 elsif Nkind
(N
) = N_Extension_Aggregate
7395 or else Convention
(Typ
) = Convention_CPP
7397 Convert_To_Assignments
(N
, Typ
);
7399 elsif not Size_Known_At_Compile_Time
(Typ
)
7400 or else not Component_OK_For_Backend
7401 or else not Static_Components
7403 Convert_To_Assignments
(N
, Typ
);
7405 -- In all other cases, build a proper aggregate to be handled by
7409 Build_Back_End_Aggregate
;
7412 -- Gigi doesn't properly handle temporaries of variable size so we
7413 -- generate it in the front-end
7415 elsif not Size_Known_At_Compile_Time
(Typ
)
7416 and then Tagged_Type_Expansion
7418 Convert_To_Assignments
(N
, Typ
);
7420 -- An aggregate used to initialize a controlled object must be turned
7421 -- into component assignments as the components themselves may require
7422 -- finalization actions such as adjustment.
7424 elsif Needs_Finalization
(Typ
) then
7425 Convert_To_Assignments
(N
, Typ
);
7427 -- Ada 2005 (AI-287): In case of default initialized components we
7428 -- convert the aggregate into assignments.
7430 elsif Has_Default_Init_Comps
(N
) then
7431 Convert_To_Assignments
(N
, Typ
);
7435 elsif not Component_OK_For_Backend
then
7436 Convert_To_Assignments
(N
, Typ
);
7438 -- If an ancestor is private, some components are not inherited and we
7439 -- cannot expand into a record aggregate.
7441 elsif Has_Visible_Private_Ancestor
(Typ
) then
7442 Convert_To_Assignments
(N
, Typ
);
7444 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
7445 -- is not able to handle the aggregate for Late_Request.
7447 elsif Is_Tagged_Type
(Typ
) and then Has_Discriminants
(Typ
) then
7448 Convert_To_Assignments
(N
, Typ
);
7450 -- If the tagged types covers interface types we need to initialize all
7451 -- hidden components containing pointers to secondary dispatch tables.
7453 elsif Is_Tagged_Type
(Typ
) and then Has_Interfaces
(Typ
) then
7454 Convert_To_Assignments
(N
, Typ
);
7456 -- If some components are mutable, the size of the aggregate component
7457 -- may be distinct from the default size of the type component, so
7458 -- we need to expand to insure that the back-end copies the proper
7459 -- size of the data. However, if the aggregate is the initial value of
7460 -- a constant, the target is immutable and might be built statically
7461 -- if components are appropriate.
7463 elsif Has_Mutable_Components
(Typ
)
7465 (Nkind
(Parent
(Top_Level_Aggr
)) /= N_Object_Declaration
7466 or else not Constant_Present
(Parent
(Top_Level_Aggr
))
7467 or else not Static_Components
)
7469 Convert_To_Assignments
(N
, Typ
);
7471 -- If the type involved has bit aligned components, then we are not sure
7472 -- that the back end can handle this case correctly.
7474 elsif Type_May_Have_Bit_Aligned_Components
(Typ
) then
7475 Convert_To_Assignments
(N
, Typ
);
7477 -- When generating C, only generate an aggregate when declaring objects
7478 -- since C does not support aggregates in e.g. assignment statements.
7480 elsif Modify_Tree_For_C
and then not In_Object_Declaration
(N
) then
7481 Convert_To_Assignments
(N
, Typ
);
7483 -- In all other cases, build a proper aggregate to be handled by gigi
7486 Build_Back_End_Aggregate
;
7488 end Expand_Record_Aggregate
;
7490 ----------------------------
7491 -- Has_Default_Init_Comps --
7492 ----------------------------
7494 function Has_Default_Init_Comps
(N
: Node_Id
) return Boolean is
7495 Comps
: constant List_Id
:= Component_Associations
(N
);
7500 pragma Assert
(Nkind_In
(N
, N_Aggregate
, N_Extension_Aggregate
));
7506 if Has_Self_Reference
(N
) then
7510 -- Check if any direct component has default initialized components
7513 while Present
(C
) loop
7514 if Box_Present
(C
) then
7521 -- Recursive call in case of aggregate expression
7524 while Present
(C
) loop
7525 Expr
:= Expression
(C
);
7528 and then Nkind_In
(Expr
, N_Aggregate
, N_Extension_Aggregate
)
7529 and then Has_Default_Init_Comps
(Expr
)
7538 end Has_Default_Init_Comps
;
7540 ----------------------------------------
7541 -- Is_Build_In_Place_Aggregate_Return --
7542 ----------------------------------------
7544 function Is_Build_In_Place_Aggregate_Return
(N
: Node_Id
) return Boolean is
7545 P
: Node_Id
:= Parent
(N
);
7548 while Nkind
(P
) = N_Qualified_Expression
loop
7552 if Nkind
(P
) = N_Simple_Return_Statement
then
7555 elsif Nkind
(Parent
(P
)) = N_Extended_Return_Statement
then
7563 Is_Build_In_Place_Function
7564 (Return_Applies_To
(Return_Statement_Entity
(P
)));
7565 end Is_Build_In_Place_Aggregate_Return
;
7567 --------------------------
7568 -- Is_Delayed_Aggregate --
7569 --------------------------
7571 function Is_Delayed_Aggregate
(N
: Node_Id
) return Boolean is
7572 Node
: Node_Id
:= N
;
7573 Kind
: Node_Kind
:= Nkind
(Node
);
7576 if Kind
= N_Qualified_Expression
then
7577 Node
:= Expression
(Node
);
7578 Kind
:= Nkind
(Node
);
7581 if not Nkind_In
(Kind
, N_Aggregate
, N_Extension_Aggregate
) then
7584 return Expansion_Delayed
(Node
);
7586 end Is_Delayed_Aggregate
;
7588 ---------------------------
7589 -- In_Object_Declaration --
7590 ---------------------------
7592 function In_Object_Declaration
(N
: Node_Id
) return Boolean is
7593 P
: Node_Id
:= Parent
(N
);
7595 while Present
(P
) loop
7596 if Nkind
(P
) = N_Object_Declaration
then
7604 end In_Object_Declaration
;
7606 ----------------------------------------
7607 -- Is_Static_Dispatch_Table_Aggregate --
7608 ----------------------------------------
7610 function Is_Static_Dispatch_Table_Aggregate
(N
: Node_Id
) return Boolean is
7611 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
7614 return Building_Static_Dispatch_Tables
7615 and then Tagged_Type_Expansion
7616 and then RTU_Loaded
(Ada_Tags
)
7618 -- Avoid circularity when rebuilding the compiler
7620 and then Cunit_Entity
(Get_Source_Unit
(N
)) /= RTU_Entity
(Ada_Tags
)
7621 and then (Typ
= RTE
(RE_Dispatch_Table_Wrapper
)
7623 Typ
= RTE
(RE_Address_Array
)
7625 Typ
= RTE
(RE_Type_Specific_Data
)
7627 Typ
= RTE
(RE_Tag_Table
)
7629 (RTE_Available
(RE_Interface_Data
)
7630 and then Typ
= RTE
(RE_Interface_Data
))
7632 (RTE_Available
(RE_Interfaces_Array
)
7633 and then Typ
= RTE
(RE_Interfaces_Array
))
7635 (RTE_Available
(RE_Interface_Data_Element
)
7636 and then Typ
= RTE
(RE_Interface_Data_Element
)));
7637 end Is_Static_Dispatch_Table_Aggregate
;
7639 -----------------------------
7640 -- Is_Two_Dim_Packed_Array --
7641 -----------------------------
7643 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean is
7644 C
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
7646 return Number_Dimensions
(Typ
) = 2
7647 and then Is_Bit_Packed_Array
(Typ
)
7648 and then (C
= 1 or else C
= 2 or else C
= 4);
7649 end Is_Two_Dim_Packed_Array
;
7651 --------------------
7652 -- Late_Expansion --
7653 --------------------
7655 function Late_Expansion
7658 Target
: Node_Id
) return List_Id
7660 Aggr_Code
: List_Id
;
7663 if Is_Array_Type
(Etype
(N
)) then
7665 Build_Array_Aggr_Code
7667 Ctype
=> Component_Type
(Etype
(N
)),
7668 Index
=> First_Index
(Typ
),
7670 Scalar_Comp
=> Is_Scalar_Type
(Component_Type
(Typ
)),
7671 Indexes
=> No_List
);
7673 -- Directly or indirectly (e.g. access protected procedure) a record
7676 Aggr_Code
:= Build_Record_Aggr_Code
(N
, Typ
, Target
);
7679 -- Save the last assignment statement associated with the aggregate
7680 -- when building a controlled object. This reference is utilized by
7681 -- the finalization machinery when marking an object as successfully
7684 if Needs_Finalization
(Typ
)
7685 and then Is_Entity_Name
(Target
)
7686 and then Present
(Entity
(Target
))
7687 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
7689 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
7695 ----------------------------------
7696 -- Make_OK_Assignment_Statement --
7697 ----------------------------------
7699 function Make_OK_Assignment_Statement
7702 Expression
: Node_Id
) return Node_Id
7705 Set_Assignment_OK
(Name
);
7706 return Make_Assignment_Statement
(Sloc
, Name
, Expression
);
7707 end Make_OK_Assignment_Statement
;
7709 -----------------------
7710 -- Number_Of_Choices --
7711 -----------------------
7713 function Number_Of_Choices
(N
: Node_Id
) return Nat
is
7717 Nb_Choices
: Nat
:= 0;
7720 if Present
(Expressions
(N
)) then
7724 Assoc
:= First
(Component_Associations
(N
));
7725 while Present
(Assoc
) loop
7726 Choice
:= First
(Choice_List
(Assoc
));
7727 while Present
(Choice
) loop
7728 if Nkind
(Choice
) /= N_Others_Choice
then
7729 Nb_Choices
:= Nb_Choices
+ 1;
7739 end Number_Of_Choices
;
7741 ------------------------------------
7742 -- Packed_Array_Aggregate_Handled --
7743 ------------------------------------
7745 -- The current version of this procedure will handle at compile time
7746 -- any array aggregate that meets these conditions:
7748 -- One and two dimensional, bit packed
7749 -- Underlying packed type is modular type
7750 -- Bounds are within 32-bit Int range
7751 -- All bounds and values are static
7753 -- Note: for now, in the 2-D case, we only handle component sizes of
7754 -- 1, 2, 4 (cases where an integral number of elements occupies a byte).
7756 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean is
7757 Loc
: constant Source_Ptr
:= Sloc
(N
);
7758 Typ
: constant Entity_Id
:= Etype
(N
);
7759 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
7761 Not_Handled
: exception;
7762 -- Exception raised if this aggregate cannot be handled
7765 -- Handle one- or two dimensional bit packed array
7767 if not Is_Bit_Packed_Array
(Typ
)
7768 or else Number_Dimensions
(Typ
) > 2
7773 -- If two-dimensional, check whether it can be folded, and transformed
7774 -- into a one-dimensional aggregate for the Packed_Array_Impl_Type of
7775 -- the original type.
7777 if Number_Dimensions
(Typ
) = 2 then
7778 return Two_Dim_Packed_Array_Handled
(N
);
7781 if not Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
)) then
7785 if not Is_Scalar_Type
(Component_Type
(Typ
))
7786 and then Has_Non_Standard_Rep
(Component_Type
(Typ
))
7792 Csiz
: constant Nat
:= UI_To_Int
(Component_Size
(Typ
));
7796 -- Bounds of index type
7800 -- Values of bounds if compile time known
7802 function Get_Component_Val
(N
: Node_Id
) return Uint
;
7803 -- Given a expression value N of the component type Ctyp, returns a
7804 -- value of Csiz (component size) bits representing this value. If
7805 -- the value is nonstatic or any other reason exists why the value
7806 -- cannot be returned, then Not_Handled is raised.
7808 -----------------------
7809 -- Get_Component_Val --
7810 -----------------------
7812 function Get_Component_Val
(N
: Node_Id
) return Uint
is
7816 -- We have to analyze the expression here before doing any further
7817 -- processing here. The analysis of such expressions is deferred
7818 -- till expansion to prevent some problems of premature analysis.
7820 Analyze_And_Resolve
(N
, Ctyp
);
7822 -- Must have a compile time value. String literals have to be
7823 -- converted into temporaries as well, because they cannot easily
7824 -- be converted into their bit representation.
7826 if not Compile_Time_Known_Value
(N
)
7827 or else Nkind
(N
) = N_String_Literal
7832 Val
:= Expr_Rep_Value
(N
);
7834 -- Adjust for bias, and strip proper number of bits
7836 if Has_Biased_Representation
(Ctyp
) then
7837 Val
:= Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
7840 return Val
mod Uint_2
** Csiz
;
7841 end Get_Component_Val
;
7843 -- Here we know we have a one dimensional bit packed array
7846 Get_Index_Bounds
(First_Index
(Typ
), Lo
, Hi
);
7848 -- Cannot do anything if bounds are dynamic
7850 if not Compile_Time_Known_Value
(Lo
)
7852 not Compile_Time_Known_Value
(Hi
)
7857 -- Or are silly out of range of int bounds
7859 Lob
:= Expr_Value
(Lo
);
7860 Hib
:= Expr_Value
(Hi
);
7862 if not UI_Is_In_Int_Range
(Lob
)
7864 not UI_Is_In_Int_Range
(Hib
)
7869 -- At this stage we have a suitable aggregate for handling at compile
7870 -- time. The only remaining checks are that the values of expressions
7871 -- in the aggregate are compile-time known (checks are performed by
7872 -- Get_Component_Val), and that any subtypes or ranges are statically
7875 -- If the aggregate is not fully positional at this stage, then
7876 -- convert it to positional form. Either this will fail, in which
7877 -- case we can do nothing, or it will succeed, in which case we have
7878 -- succeeded in handling the aggregate and transforming it into a
7879 -- modular value, or it will stay an aggregate, in which case we
7880 -- have failed to create a packed value for it.
7882 if Present
(Component_Associations
(N
)) then
7883 Convert_To_Positional
7884 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
7885 return Nkind
(N
) /= N_Aggregate
;
7888 -- Otherwise we are all positional, so convert to proper value
7891 Lov
: constant Int
:= UI_To_Int
(Lob
);
7892 Hiv
: constant Int
:= UI_To_Int
(Hib
);
7894 Len
: constant Nat
:= Int
'Max (0, Hiv
- Lov
+ 1);
7895 -- The length of the array (number of elements)
7897 Aggregate_Val
: Uint
;
7898 -- Value of aggregate. The value is set in the low order bits of
7899 -- this value. For the little-endian case, the values are stored
7900 -- from low-order to high-order and for the big-endian case the
7901 -- values are stored from high-order to low-order. Note that gigi
7902 -- will take care of the conversions to left justify the value in
7903 -- the big endian case (because of left justified modular type
7904 -- processing), so we do not have to worry about that here.
7907 -- Integer literal for resulting constructed value
7910 -- Shift count from low order for next value
7913 -- Shift increment for loop
7916 -- Next expression from positional parameters of aggregate
7918 Left_Justified
: Boolean;
7919 -- Set True if we are filling the high order bits of the target
7920 -- value (i.e. the value is left justified).
7923 -- For little endian, we fill up the low order bits of the target
7924 -- value. For big endian we fill up the high order bits of the
7925 -- target value (which is a left justified modular value).
7927 Left_Justified
:= Bytes_Big_Endian
;
7929 -- Switch justification if using -gnatd8
7931 if Debug_Flag_8
then
7932 Left_Justified
:= not Left_Justified
;
7935 -- Switch justfification if reverse storage order
7937 if Reverse_Storage_Order
(Base_Type
(Typ
)) then
7938 Left_Justified
:= not Left_Justified
;
7941 if Left_Justified
then
7942 Shift
:= Csiz
* (Len
- 1);
7949 -- Loop to set the values
7952 Aggregate_Val
:= Uint_0
;
7954 Expr
:= First
(Expressions
(N
));
7955 Aggregate_Val
:= Get_Component_Val
(Expr
) * Uint_2
** Shift
;
7957 for J
in 2 .. Len
loop
7958 Shift
:= Shift
+ Incr
;
7961 Aggregate_Val
+ Get_Component_Val
(Expr
) * Uint_2
** Shift
;
7965 -- Now we can rewrite with the proper value
7967 Lit
:= Make_Integer_Literal
(Loc
, Intval
=> Aggregate_Val
);
7968 Set_Print_In_Hex
(Lit
);
7970 -- Construct the expression using this literal. Note that it is
7971 -- important to qualify the literal with its proper modular type
7972 -- since universal integer does not have the required range and
7973 -- also this is a left justified modular type, which is important
7974 -- in the big-endian case.
7977 Unchecked_Convert_To
(Typ
,
7978 Make_Qualified_Expression
(Loc
,
7980 New_Occurrence_Of
(Packed_Array_Impl_Type
(Typ
), Loc
),
7981 Expression
=> Lit
)));
7983 Analyze_And_Resolve
(N
, Typ
);
7991 end Packed_Array_Aggregate_Handled
;
7993 ----------------------------
7994 -- Has_Mutable_Components --
7995 ----------------------------
7997 function Has_Mutable_Components
(Typ
: Entity_Id
) return Boolean is
8001 Comp
:= First_Component
(Typ
);
8002 while Present
(Comp
) loop
8003 if Is_Record_Type
(Etype
(Comp
))
8004 and then Has_Discriminants
(Etype
(Comp
))
8005 and then not Is_Constrained
(Etype
(Comp
))
8010 Next_Component
(Comp
);
8014 end Has_Mutable_Components
;
8016 ------------------------------
8017 -- Initialize_Discriminants --
8018 ------------------------------
8020 procedure Initialize_Discriminants
(N
: Node_Id
; Typ
: Entity_Id
) is
8021 Loc
: constant Source_Ptr
:= Sloc
(N
);
8022 Bas
: constant Entity_Id
:= Base_Type
(Typ
);
8023 Par
: constant Entity_Id
:= Etype
(Bas
);
8024 Decl
: constant Node_Id
:= Parent
(Par
);
8028 if Is_Tagged_Type
(Bas
)
8029 and then Is_Derived_Type
(Bas
)
8030 and then Has_Discriminants
(Par
)
8031 and then Has_Discriminants
(Bas
)
8032 and then Number_Discriminants
(Bas
) /= Number_Discriminants
(Par
)
8033 and then Nkind
(Decl
) = N_Full_Type_Declaration
8034 and then Nkind
(Type_Definition
(Decl
)) = N_Record_Definition
8036 Present
(Variant_Part
(Component_List
(Type_Definition
(Decl
))))
8037 and then Nkind
(N
) /= N_Extension_Aggregate
8040 -- Call init proc to set discriminants.
8041 -- There should eventually be a special procedure for this ???
8043 Ref
:= New_Occurrence_Of
(Defining_Identifier
(N
), Loc
);
8044 Insert_Actions_After
(N
,
8045 Build_Initialization_Call
(Sloc
(N
), Ref
, Typ
));
8047 end Initialize_Discriminants
;
8054 (Obj_Type
: Entity_Id
;
8055 Typ
: Entity_Id
) return Boolean
8057 L1
, L2
, H1
, H2
: Node_Id
;
8060 -- No sliding if the type of the object is not established yet, if it is
8061 -- an unconstrained type whose actual subtype comes from the aggregate,
8062 -- or if the two types are identical.
8064 if not Is_Array_Type
(Obj_Type
) then
8067 elsif not Is_Constrained
(Obj_Type
) then
8070 elsif Typ
= Obj_Type
then
8074 -- Sliding can only occur along the first dimension
8076 Get_Index_Bounds
(First_Index
(Typ
), L1
, H1
);
8077 Get_Index_Bounds
(First_Index
(Obj_Type
), L2
, H2
);
8079 if not Is_OK_Static_Expression
(L1
) or else
8080 not Is_OK_Static_Expression
(L2
) or else
8081 not Is_OK_Static_Expression
(H1
) or else
8082 not Is_OK_Static_Expression
(H2
)
8086 return Expr_Value
(L1
) /= Expr_Value
(L2
)
8088 Expr_Value
(H1
) /= Expr_Value
(H2
);
8093 ---------------------------------
8094 -- Process_Transient_Component --
8095 ---------------------------------
8097 procedure Process_Transient_Component
8099 Comp_Typ
: Entity_Id
;
8100 Init_Expr
: Node_Id
;
8101 Fin_Call
: out Node_Id
;
8102 Hook_Clear
: out Node_Id
;
8103 Aggr
: Node_Id
:= Empty
;
8104 Stmts
: List_Id
:= No_List
)
8106 procedure Add_Item
(Item
: Node_Id
);
8107 -- Insert arbitrary node Item into the tree depending on the values of
8114 procedure Add_Item
(Item
: Node_Id
) is
8116 if Present
(Aggr
) then
8117 Insert_Action
(Aggr
, Item
);
8119 pragma Assert
(Present
(Stmts
));
8120 Append_To
(Stmts
, Item
);
8126 Hook_Assign
: Node_Id
;
8127 Hook_Decl
: Node_Id
;
8131 Res_Typ
: Entity_Id
;
8133 -- Start of processing for Process_Transient_Component
8136 -- Add the access type, which provides a reference to the function
8137 -- result. Generate:
8139 -- type Res_Typ is access all Comp_Typ;
8141 Res_Typ
:= Make_Temporary
(Loc
, 'A');
8142 Set_Ekind
(Res_Typ
, E_General_Access_Type
);
8143 Set_Directly_Designated_Type
(Res_Typ
, Comp_Typ
);
8146 (Make_Full_Type_Declaration
(Loc
,
8147 Defining_Identifier
=> Res_Typ
,
8149 Make_Access_To_Object_Definition
(Loc
,
8150 All_Present
=> True,
8151 Subtype_Indication
=> New_Occurrence_Of
(Comp_Typ
, Loc
))));
8153 -- Add the temporary which captures the result of the function call.
8156 -- Res : constant Res_Typ := Init_Expr'Reference;
8158 -- Note that this temporary is effectively a transient object because
8159 -- its lifetime is bounded by the current array or record component.
8161 Res_Id
:= Make_Temporary
(Loc
, 'R');
8162 Set_Ekind
(Res_Id
, E_Constant
);
8163 Set_Etype
(Res_Id
, Res_Typ
);
8165 -- Mark the transient object as successfully processed to avoid double
8168 Set_Is_Finalized_Transient
(Res_Id
);
8170 -- Signal the general finalization machinery that this transient object
8171 -- should not be considered for finalization actions because its cleanup
8172 -- will be performed by Process_Transient_Component_Completion.
8174 Set_Is_Ignored_Transient
(Res_Id
);
8177 Make_Object_Declaration
(Loc
,
8178 Defining_Identifier
=> Res_Id
,
8179 Constant_Present
=> True,
8180 Object_Definition
=> New_Occurrence_Of
(Res_Typ
, Loc
),
8182 Make_Reference
(Loc
, New_Copy_Tree
(Init_Expr
)));
8184 Add_Item
(Res_Decl
);
8186 -- Construct all pieces necessary to hook and finalize the transient
8189 Build_Transient_Object_Statements
8190 (Obj_Decl
=> Res_Decl
,
8191 Fin_Call
=> Fin_Call
,
8192 Hook_Assign
=> Hook_Assign
,
8193 Hook_Clear
=> Hook_Clear
,
8194 Hook_Decl
=> Hook_Decl
,
8195 Ptr_Decl
=> Ptr_Decl
);
8197 -- Add the access type which provides a reference to the transient
8198 -- result. Generate:
8200 -- type Ptr_Typ is access all Comp_Typ;
8202 Add_Item
(Ptr_Decl
);
8204 -- Add the temporary which acts as a hook to the transient result.
8207 -- Hook : Ptr_Typ := null;
8209 Add_Item
(Hook_Decl
);
8211 -- Attach the transient result to the hook. Generate:
8213 -- Hook := Ptr_Typ (Res);
8215 Add_Item
(Hook_Assign
);
8217 -- The original initialization expression now references the value of
8218 -- the temporary function result. Generate:
8223 Make_Explicit_Dereference
(Loc
,
8224 Prefix
=> New_Occurrence_Of
(Res_Id
, Loc
)));
8225 end Process_Transient_Component
;
8227 --------------------------------------------
8228 -- Process_Transient_Component_Completion --
8229 --------------------------------------------
8231 procedure Process_Transient_Component_Completion
8235 Hook_Clear
: Node_Id
;
8238 Exceptions_OK
: constant Boolean :=
8239 not Restriction_Active
(No_Exception_Propagation
);
8242 pragma Assert
(Present
(Hook_Clear
));
8244 -- Generate the following code if exception propagation is allowed:
8247 -- Abort : constant Boolean := Triggered_By_Abort;
8249 -- Abort : constant Boolean := False; -- no abort
8251 -- E : Exception_Occurrence;
8252 -- Raised : Boolean := False;
8259 -- [Deep_]Finalize (Res.all);
8263 -- if not Raised then
8265 -- Save_Occurrence (E,
8266 -- Get_Curent_Excep.all.all);
8272 -- if Raised and then not Abort then
8273 -- Raise_From_Controlled_Operation (E);
8277 if Exceptions_OK
then
8278 Abort_And_Exception
: declare
8279 Blk_Decls
: constant List_Id
:= New_List
;
8280 Blk_Stmts
: constant List_Id
:= New_List
;
8281 Fin_Stmts
: constant List_Id
:= New_List
;
8283 Fin_Data
: Finalization_Exception_Data
;
8286 -- Create the declarations of the two flags and the exception
8289 Build_Object_Declarations
(Fin_Data
, Blk_Decls
, Loc
);
8294 if Abort_Allowed
then
8295 Append_To
(Blk_Stmts
,
8296 Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
8299 -- Wrap the hook clear and the finalization call in order to trap
8300 -- a potential exception.
8302 Append_To
(Fin_Stmts
, Hook_Clear
);
8304 if Present
(Fin_Call
) then
8305 Append_To
(Fin_Stmts
, Fin_Call
);
8308 Append_To
(Blk_Stmts
,
8309 Make_Block_Statement
(Loc
,
8310 Handled_Statement_Sequence
=>
8311 Make_Handled_Sequence_Of_Statements
(Loc
,
8312 Statements
=> Fin_Stmts
,
8313 Exception_Handlers
=> New_List
(
8314 Build_Exception_Handler
(Fin_Data
)))));
8319 if Abort_Allowed
then
8320 Append_To
(Blk_Stmts
,
8321 Build_Runtime_Call
(Loc
, RE_Abort_Undefer
));
8324 -- Reraise the potential exception with a proper "upgrade" to
8325 -- Program_Error if needed.
8327 Append_To
(Blk_Stmts
, Build_Raise_Statement
(Fin_Data
));
8329 -- Wrap everything in a block
8332 Make_Block_Statement
(Loc
,
8333 Declarations
=> Blk_Decls
,
8334 Handled_Statement_Sequence
=>
8335 Make_Handled_Sequence_Of_Statements
(Loc
,
8336 Statements
=> Blk_Stmts
)));
8337 end Abort_And_Exception
;
8339 -- Generate the following code if exception propagation is not allowed
8340 -- and aborts are allowed:
8345 -- [Deep_]Finalize (Res.all);
8347 -- Abort_Undefer_Direct;
8350 elsif Abort_Allowed
then
8351 Abort_Only
: declare
8352 Blk_Stmts
: constant List_Id
:= New_List
;
8355 Append_To
(Blk_Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
8356 Append_To
(Blk_Stmts
, Hook_Clear
);
8358 if Present
(Fin_Call
) then
8359 Append_To
(Blk_Stmts
, Fin_Call
);
8363 Build_Abort_Undefer_Block
(Loc
,
8368 -- Otherwise generate:
8371 -- [Deep_]Finalize (Res.all);
8374 Append_To
(Stmts
, Hook_Clear
);
8376 if Present
(Fin_Call
) then
8377 Append_To
(Stmts
, Fin_Call
);
8380 end Process_Transient_Component_Completion
;
8382 ---------------------
8383 -- Sort_Case_Table --
8384 ---------------------
8386 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
) is
8387 L
: constant Int
:= Case_Table
'First;
8388 U
: constant Int
:= Case_Table
'Last;
8396 T
:= Case_Table
(K
+ 1);
8400 and then Expr_Value
(Case_Table
(J
- 1).Choice_Lo
) >
8401 Expr_Value
(T
.Choice_Lo
)
8403 Case_Table
(J
) := Case_Table
(J
- 1);
8407 Case_Table
(J
) := T
;
8410 end Sort_Case_Table
;
8412 ----------------------------
8413 -- Static_Array_Aggregate --
8414 ----------------------------
8416 function Static_Array_Aggregate
(N
: Node_Id
) return Boolean is
8417 Bounds
: constant Node_Id
:= Aggregate_Bounds
(N
);
8419 Typ
: constant Entity_Id
:= Etype
(N
);
8420 Comp_Type
: constant Entity_Id
:= Component_Type
(Typ
);
8427 if Is_Tagged_Type
(Typ
)
8428 or else Is_Controlled
(Typ
)
8429 or else Is_Packed
(Typ
)
8435 and then Nkind
(Bounds
) = N_Range
8436 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
8437 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
8439 Lo
:= Low_Bound
(Bounds
);
8440 Hi
:= High_Bound
(Bounds
);
8442 if No
(Component_Associations
(N
)) then
8444 -- Verify that all components are static integers
8446 Expr
:= First
(Expressions
(N
));
8447 while Present
(Expr
) loop
8448 if Nkind
(Expr
) /= N_Integer_Literal
then
8458 -- We allow only a single named association, either a static
8459 -- range or an others_clause, with a static expression.
8461 Expr
:= First
(Component_Associations
(N
));
8463 if Present
(Expressions
(N
)) then
8466 elsif Present
(Next
(Expr
)) then
8469 elsif Present
(Next
(First
(Choice_List
(Expr
)))) then
8473 -- The aggregate is static if all components are literals,
8474 -- or else all its components are static aggregates for the
8475 -- component type. We also limit the size of a static aggregate
8476 -- to prevent runaway static expressions.
8478 if Is_Array_Type
(Comp_Type
)
8479 or else Is_Record_Type
(Comp_Type
)
8481 if Nkind
(Expression
(Expr
)) /= N_Aggregate
8483 not Compile_Time_Known_Aggregate
(Expression
(Expr
))
8488 elsif Nkind
(Expression
(Expr
)) /= N_Integer_Literal
then
8492 if not Aggr_Size_OK
(N
, Typ
) then
8496 -- Create a positional aggregate with the right number of
8497 -- copies of the expression.
8499 Agg
:= Make_Aggregate
(Sloc
(N
), New_List
, No_List
);
8501 for I
in UI_To_Int
(Intval
(Lo
)) .. UI_To_Int
(Intval
(Hi
))
8503 Append_To
(Expressions
(Agg
), New_Copy
(Expression
(Expr
)));
8505 -- The copied expression must be analyzed and resolved.
8506 -- Besides setting the type, this ensures that static
8507 -- expressions are appropriately marked as such.
8510 (Last
(Expressions
(Agg
)), Component_Type
(Typ
));
8513 Set_Aggregate_Bounds
(Agg
, Bounds
);
8514 Set_Etype
(Agg
, Typ
);
8517 Set_Compile_Time_Known_Aggregate
(N
);
8526 end Static_Array_Aggregate
;
8528 ----------------------------------
8529 -- Two_Dim_Packed_Array_Handled --
8530 ----------------------------------
8532 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean is
8533 Loc
: constant Source_Ptr
:= Sloc
(N
);
8534 Typ
: constant Entity_Id
:= Etype
(N
);
8535 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
8536 Comp_Size
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
8537 Packed_Array
: constant Entity_Id
:=
8538 Packed_Array_Impl_Type
(Base_Type
(Typ
));
8541 -- Expression in original aggregate
8544 -- One-dimensional subaggregate
8548 -- For now, only deal with cases where an integral number of elements
8549 -- fit in a single byte. This includes the most common boolean case.
8551 if not (Comp_Size
= 1 or else
8552 Comp_Size
= 2 or else
8558 Convert_To_Positional
8559 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
8561 -- Verify that all components are static
8563 if Nkind
(N
) = N_Aggregate
8564 and then Compile_Time_Known_Aggregate
(N
)
8568 -- The aggregate may have been reanalyzed and converted already
8570 elsif Nkind
(N
) /= N_Aggregate
then
8573 -- If component associations remain, the aggregate is not static
8575 elsif Present
(Component_Associations
(N
)) then
8579 One_Dim
:= First
(Expressions
(N
));
8580 while Present
(One_Dim
) loop
8581 if Present
(Component_Associations
(One_Dim
)) then
8585 One_Comp
:= First
(Expressions
(One_Dim
));
8586 while Present
(One_Comp
) loop
8587 if not Is_OK_Static_Expression
(One_Comp
) then
8598 -- Two-dimensional aggregate is now fully positional so pack one
8599 -- dimension to create a static one-dimensional array, and rewrite
8600 -- as an unchecked conversion to the original type.
8603 Byte_Size
: constant Int
:= UI_To_Int
(Component_Size
(Packed_Array
));
8604 -- The packed array type is a byte array
8607 -- Number of components accumulated in current byte
8610 -- Assembled list of packed values for equivalent aggregate
8613 -- Integer value of component
8616 -- Step size for packing
8619 -- Endian-dependent start position for packing
8622 -- Current insertion position
8625 -- Component of packed array being assembled
8632 -- Account for endianness. See corresponding comment in
8633 -- Packed_Array_Aggregate_Handled concerning the following.
8637 xor Reverse_Storage_Order
(Base_Type
(Typ
))
8639 Init_Shift
:= Byte_Size
- Comp_Size
;
8646 -- Iterate over each subaggregate
8648 Shift
:= Init_Shift
;
8649 One_Dim
:= First
(Expressions
(N
));
8650 while Present
(One_Dim
) loop
8651 One_Comp
:= First
(Expressions
(One_Dim
));
8652 while Present
(One_Comp
) loop
8653 if Packed_Num
= Byte_Size
/ Comp_Size
then
8655 -- Byte is complete, add to list of expressions
8657 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
8659 Shift
:= Init_Shift
;
8663 Comp_Val
:= Expr_Rep_Value
(One_Comp
);
8665 -- Adjust for bias, and strip proper number of bits
8667 if Has_Biased_Representation
(Ctyp
) then
8668 Comp_Val
:= Comp_Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
8671 Comp_Val
:= Comp_Val
mod Uint_2
** Comp_Size
;
8672 Val
:= UI_To_Int
(Val
+ Comp_Val
* Uint_2
** Shift
);
8673 Shift
:= Shift
+ Incr
;
8674 One_Comp
:= Next
(One_Comp
);
8675 Packed_Num
:= Packed_Num
+ 1;
8679 One_Dim
:= Next
(One_Dim
);
8682 if Packed_Num
> 0 then
8684 -- Add final incomplete byte if present
8686 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
8690 Unchecked_Convert_To
(Typ
,
8691 Make_Qualified_Expression
(Loc
,
8692 Subtype_Mark
=> New_Occurrence_Of
(Packed_Array
, Loc
),
8693 Expression
=> Make_Aggregate
(Loc
, Expressions
=> Comps
))));
8694 Analyze_And_Resolve
(N
);
8697 end Two_Dim_Packed_Array_Handled
;