1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2017, 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 non-static 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
:= 5;
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 5 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 -- It would seem useful to have a higher default for Max_Others_Replicate,
305 -- but aggregates in the compiler make this impossible: the compiler
306 -- bootstrap fails if Max_Others_Replicate is greater than 25. This
309 procedure Expand_Array_Aggregate
(N
: Node_Id
);
310 -- This is the top-level routine to perform array aggregate expansion.
311 -- N is the N_Aggregate node to be expanded.
313 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean;
314 -- For two-dimensional packed aggregates with constant bounds and constant
315 -- components, it is preferable to pack the inner aggregates because the
316 -- whole matrix can then be presented to the back-end as a one-dimensional
317 -- list of literals. This is much more efficient than expanding into single
318 -- component assignments. This function determines if the type Typ is for
319 -- an array that is suitable for this optimization: it returns True if Typ
320 -- is a two dimensional bit packed array with component size 1, 2, or 4.
322 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean;
323 -- Given an array aggregate, this function handles the case of a packed
324 -- array aggregate with all constant values, where the aggregate can be
325 -- evaluated at compile time. If this is possible, then N is rewritten
326 -- to be its proper compile time value with all the components properly
327 -- assembled. The expression is analyzed and resolved and True is returned.
328 -- If this transformation is not possible, N is unchanged and False is
331 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean;
332 -- If the type of the aggregate is a two-dimensional bit_packed array
333 -- it may be transformed into an array of bytes with constant values,
334 -- and presented to the back-end as a static value. The function returns
335 -- false if this transformation cannot be performed. THis is similar to,
336 -- and reuses part of the machinery in Packed_Array_Aggregate_Handled.
342 function Aggr_Size_OK
(N
: Node_Id
; Typ
: Entity_Id
) return Boolean is
351 -- Determines the maximum size of an array aggregate produced by
352 -- converting named to positional notation (e.g. from others clauses).
353 -- This avoids running away with attempts to convert huge aggregates,
354 -- which hit memory limits in the backend.
356 function Component_Count
(T
: Entity_Id
) return Nat
;
357 -- The limit is applied to the total number of subcomponents that the
358 -- aggregate will have, which is the number of static expressions
359 -- that will appear in the flattened array. This requires a recursive
360 -- computation of the number of scalar components of the structure.
362 ---------------------
363 -- Component_Count --
364 ---------------------
366 function Component_Count
(T
: Entity_Id
) return Nat
is
371 if Is_Scalar_Type
(T
) then
374 elsif Is_Record_Type
(T
) then
375 Comp
:= First_Component
(T
);
376 while Present
(Comp
) loop
377 Res
:= Res
+ Component_Count
(Etype
(Comp
));
378 Next_Component
(Comp
);
383 elsif Is_Array_Type
(T
) then
385 Lo
: constant Node_Id
:=
386 Type_Low_Bound
(Etype
(First_Index
(T
)));
387 Hi
: constant Node_Id
:=
388 Type_High_Bound
(Etype
(First_Index
(T
)));
390 Siz
: constant Nat
:= Component_Count
(Component_Type
(T
));
393 -- Check for superflat arrays, i.e. arrays with such bounds
394 -- as 4 .. 2, to insure that this function never returns a
395 -- meaningless negative value.
397 if not Compile_Time_Known_Value
(Lo
)
398 or else not Compile_Time_Known_Value
(Hi
)
399 or else Expr_Value
(Hi
) < Expr_Value
(Lo
)
404 -- If the number of components is greater than Int'Last,
405 -- then return Int'Last, so caller will return False (Aggr
406 -- size is not OK). Otherwise, UI_To_Int will crash.
409 UI
: constant Uint
:=
410 Expr_Value
(Hi
) - Expr_Value
(Lo
) + 1;
412 if UI_Is_In_Int_Range
(UI
) then
413 return Siz
* UI_To_Int
(UI
);
422 -- Can only be a null for an access type
428 -- Start of processing for Aggr_Size_OK
431 -- The normal aggregate limit is 500000, but we increase this limit to
432 -- 2**24 (about 16 million) if Restrictions (No_Elaboration_Code) or
433 -- Restrictions (No_Implicit_Loops) is specified, since in either case
434 -- we are at risk of declaring the program illegal because of this
435 -- limit. We also increase the limit when Static_Elaboration_Desired,
436 -- given that this means that objects are intended to be placed in data
439 -- We also increase the limit if the aggregate is for a packed two-
440 -- dimensional array, because if components are static it is much more
441 -- efficient to construct a one-dimensional equivalent array with static
444 -- Conversely, we decrease the maximum size if none of the above
445 -- requirements apply, and if the aggregate has a single component
446 -- association, which will be more efficient if implemented with a loop.
448 -- Finally, we use a small limit in CodePeer mode where we favor loops
449 -- instead of thousands of single assignments (from large aggregates).
451 Max_Aggr_Size
:= 500000;
453 if CodePeer_Mode
then
454 Max_Aggr_Size
:= 100;
456 elsif Restriction_Active
(No_Elaboration_Code
)
457 or else Restriction_Active
(No_Implicit_Loops
)
458 or else Is_Two_Dim_Packed_Array
(Typ
)
459 or else (Ekind
(Current_Scope
) = E_Package
460 and then Static_Elaboration_Desired
(Current_Scope
))
462 Max_Aggr_Size
:= 2 ** 24;
464 elsif No
(Expressions
(N
))
465 and then No
(Next
(First
(Component_Associations
(N
))))
467 Max_Aggr_Size
:= 5000;
470 Siz
:= Component_Count
(Component_Type
(Typ
));
472 Indx
:= First_Index
(Typ
);
473 while Present
(Indx
) loop
474 Lo
:= Type_Low_Bound
(Etype
(Indx
));
475 Hi
:= Type_High_Bound
(Etype
(Indx
));
477 -- Bounds need to be known at compile time
479 if not Compile_Time_Known_Value
(Lo
)
480 or else not Compile_Time_Known_Value
(Hi
)
485 Lov
:= Expr_Value
(Lo
);
486 Hiv
:= Expr_Value
(Hi
);
488 -- A flat array is always safe
494 -- One-component aggregates are suspicious, and if the context type
495 -- is an object declaration with non-static bounds it will trip gcc;
496 -- such an aggregate must be expanded into a single assignment.
498 if Hiv
= Lov
and then Nkind
(Parent
(N
)) = N_Object_Declaration
then
500 Index_Type
: constant Entity_Id
:=
502 (First_Index
(Etype
(Defining_Identifier
(Parent
(N
)))));
506 if not Compile_Time_Known_Value
(Type_Low_Bound
(Index_Type
))
507 or else not Compile_Time_Known_Value
508 (Type_High_Bound
(Index_Type
))
510 if Present
(Component_Associations
(N
)) then
513 (Choice_List
(First
(Component_Associations
(N
))));
515 if Is_Entity_Name
(Indx
)
516 and then not Is_Type
(Entity
(Indx
))
519 ("single component aggregate in "
520 & "non-static context??", Indx
);
521 Error_Msg_N
("\maybe subtype name was meant??", Indx
);
531 Rng
: constant Uint
:= Hiv
- Lov
+ 1;
534 -- Check if size is too large
536 if not UI_Is_In_Int_Range
(Rng
) then
540 Siz
:= Siz
* UI_To_Int
(Rng
);
544 or else Siz
> Max_Aggr_Size
549 -- Bounds must be in integer range, for later array construction
551 if not UI_Is_In_Int_Range
(Lov
)
553 not UI_Is_In_Int_Range
(Hiv
)
564 ---------------------------------
565 -- Backend_Processing_Possible --
566 ---------------------------------
568 -- Backend processing by Gigi/gcc is possible only if all the following
569 -- conditions are met:
571 -- 1. N is fully positional
573 -- 2. N is not a bit-packed array aggregate;
575 -- 3. The size of N's array type must be known at compile time. Note
576 -- that this implies that the component size is also known
578 -- 4. The array type of N does not follow the Fortran layout convention
579 -- or if it does it must be 1 dimensional.
581 -- 5. The array component type may not be tagged (which could necessitate
582 -- reassignment of proper tags).
584 -- 6. The array component type must not have unaligned bit components
586 -- 7. None of the components of the aggregate may be bit unaligned
589 -- 8. There cannot be delayed components, since we do not know enough
590 -- at this stage to know if back end processing is possible.
592 -- 9. There cannot be any discriminated record components, since the
593 -- back end cannot handle this complex case.
595 -- 10. No controlled actions need to be generated for components
597 -- 11. When generating C code, N must be part of a N_Object_Declaration
599 -- 12. When generating C code, N must not include function calls
601 function Backend_Processing_Possible
(N
: Node_Id
) return Boolean is
602 Typ
: constant Entity_Id
:= Etype
(N
);
603 -- Typ is the correct constrained array subtype of the aggregate
605 function Component_Check
(N
: Node_Id
; Index
: Node_Id
) return Boolean;
606 -- This routine checks components of aggregate N, enforcing checks
607 -- 1, 7, 8, 9, 11, and 12. In the multidimensional case, these checks
608 -- are performed on subaggregates. The Index value is the current index
609 -- being checked in the multidimensional case.
611 ---------------------
612 -- Component_Check --
613 ---------------------
615 function Component_Check
(N
: Node_Id
; Index
: Node_Id
) return Boolean is
616 function Ultimate_Original_Expression
(N
: Node_Id
) return Node_Id
;
617 -- Given a type conversion or an unchecked type conversion N, return
618 -- its innermost original expression.
620 ----------------------------------
621 -- Ultimate_Original_Expression --
622 ----------------------------------
624 function Ultimate_Original_Expression
(N
: Node_Id
) return Node_Id
is
625 Expr
: Node_Id
:= Original_Node
(N
);
628 while Nkind_In
(Expr
, N_Type_Conversion
,
629 N_Unchecked_Type_Conversion
)
631 Expr
:= Original_Node
(Expression
(Expr
));
635 end Ultimate_Original_Expression
;
641 -- Start of processing for Component_Check
644 -- Checks 1: (no component associations)
646 if Present
(Component_Associations
(N
)) then
650 -- Checks 11: The C code generator cannot handle aggregates that are
651 -- not part of an object declaration.
653 if Modify_Tree_For_C
then
655 Par
: Node_Id
:= Parent
(N
);
658 -- Skip enclosing nested aggregates and their qualified
661 while Nkind
(Par
) = N_Aggregate
662 or else Nkind
(Par
) = N_Qualified_Expression
667 if Nkind
(Par
) /= N_Object_Declaration
then
673 -- Checks on components
675 -- Recurse to check subaggregates, which may appear in qualified
676 -- expressions. If delayed, the front-end will have to expand.
677 -- If the component is a discriminated record, treat as non-static,
678 -- as the back-end cannot handle this properly.
680 Expr
:= First
(Expressions
(N
));
681 while Present
(Expr
) loop
683 -- Checks 8: (no delayed components)
685 if Is_Delayed_Aggregate
(Expr
) then
689 -- Checks 9: (no discriminated records)
691 if Present
(Etype
(Expr
))
692 and then Is_Record_Type
(Etype
(Expr
))
693 and then Has_Discriminants
(Etype
(Expr
))
698 -- Checks 7. Component must not be bit aligned component
700 if Possible_Bit_Aligned_Component
(Expr
) then
704 -- Checks 12: (no function call)
708 Nkind
(Ultimate_Original_Expression
(Expr
)) = N_Function_Call
713 -- Recursion to following indexes for multiple dimension case
715 if Present
(Next_Index
(Index
))
716 and then not Component_Check
(Expr
, Next_Index
(Index
))
721 -- All checks for that component finished, on to next
729 -- Start of processing for Backend_Processing_Possible
732 -- Checks 2 (array not bit packed) and 10 (no controlled actions)
734 if Is_Bit_Packed_Array
(Typ
) or else Needs_Finalization
(Typ
) then
738 -- If component is limited, aggregate must be expanded because each
739 -- component assignment must be built in place.
741 if Is_Limited_View
(Component_Type
(Typ
)) then
745 -- Checks 4 (array must not be multidimensional Fortran case)
747 if Convention
(Typ
) = Convention_Fortran
748 and then Number_Dimensions
(Typ
) > 1
753 -- Checks 3 (size of array must be known at compile time)
755 if not Size_Known_At_Compile_Time
(Typ
) then
759 -- Checks on components
761 if not Component_Check
(N
, First_Index
(Typ
)) then
765 -- Checks 5 (if the component type is tagged, then we may need to do
766 -- tag adjustments. Perhaps this should be refined to check for any
767 -- component associations that actually need tag adjustment, similar
768 -- to the test in Component_OK_For_Backend for record aggregates with
769 -- tagged components, but not clear whether it's worthwhile ???; in the
770 -- case of virtual machines (no Tagged_Type_Expansion), object tags are
771 -- handled implicitly).
773 if Is_Tagged_Type
(Component_Type
(Typ
))
774 and then Tagged_Type_Expansion
779 -- Checks 6 (component type must not have bit aligned components)
781 if Type_May_Have_Bit_Aligned_Components
(Component_Type
(Typ
)) then
785 -- Backend processing is possible
787 Set_Size_Known_At_Compile_Time
(Etype
(N
), True);
789 end Backend_Processing_Possible
;
791 ---------------------------
792 -- Build_Array_Aggr_Code --
793 ---------------------------
795 -- The code that we generate from a one dimensional aggregate is
797 -- 1. If the subaggregate contains discrete choices we
799 -- (a) Sort the discrete choices
801 -- (b) Otherwise for each discrete choice that specifies a range we
802 -- emit a loop. If a range specifies a maximum of three values, or
803 -- we are dealing with an expression we emit a sequence of
804 -- assignments instead of a loop.
806 -- (c) Generate the remaining loops to cover the others choice if any
808 -- 2. If the aggregate contains positional elements we
810 -- (a) translate the positional elements in a series of assignments
812 -- (b) Generate a final loop to cover the others choice if any.
813 -- Note that this final loop has to be a while loop since the case
815 -- L : Integer := Integer'Last;
816 -- H : Integer := Integer'Last;
817 -- A : array (L .. H) := (1, others =>0);
819 -- cannot be handled by a for loop. Thus for the following
821 -- array (L .. H) := (.. positional elements.., others =>E);
823 -- we always generate something like:
825 -- J : Index_Type := Index_Of_Last_Positional_Element;
827 -- J := Index_Base'Succ (J)
831 function Build_Array_Aggr_Code
836 Scalar_Comp
: Boolean;
837 Indexes
: List_Id
:= No_List
) return List_Id
839 Loc
: constant Source_Ptr
:= Sloc
(N
);
840 Index_Base
: constant Entity_Id
:= Base_Type
(Etype
(Index
));
841 Index_Base_L
: constant Node_Id
:= Type_Low_Bound
(Index_Base
);
842 Index_Base_H
: constant Node_Id
:= Type_High_Bound
(Index_Base
);
844 function Add
(Val
: Int
; To
: Node_Id
) return Node_Id
;
845 -- Returns an expression where Val is added to expression To, unless
846 -- To+Val is provably out of To's base type range. To must be an
847 -- already analyzed expression.
849 function Empty_Range
(L
, H
: Node_Id
) return Boolean;
850 -- Returns True if the range defined by L .. H is certainly empty
852 function Equal
(L
, H
: Node_Id
) return Boolean;
853 -- Returns True if L = H for sure
855 function Index_Base_Name
return Node_Id
;
856 -- Returns a new reference to the index type name
861 In_Loop
: Boolean := False) return List_Id
;
862 -- Ind must be a side-effect-free expression. If the input aggregate N
863 -- to Build_Loop contains no subaggregates, then this function returns
864 -- the assignment statement:
866 -- Into (Indexes, Ind) := Expr;
868 -- Otherwise we call Build_Code recursively. Flag In_Loop should be set
869 -- when the assignment appears within a generated loop.
871 -- Ada 2005 (AI-287): In case of default initialized component, Expr
872 -- is empty and we generate a call to the corresponding IP subprogram.
874 function Gen_Loop
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
;
875 -- Nodes L and H must be side-effect-free expressions. If the input
876 -- aggregate N to Build_Loop contains no subaggregates, this routine
877 -- returns the for loop statement:
879 -- for J in Index_Base'(L) .. Index_Base'(H) loop
880 -- Into (Indexes, J) := Expr;
883 -- Otherwise we call Build_Code recursively. As an optimization if the
884 -- loop covers 3 or fewer scalar elements we generate a sequence of
886 -- If the component association that generates the loop comes from an
887 -- Iterated_Component_Association, the loop parameter has the name of
888 -- the corresponding parameter in the original construct.
890 function Gen_While
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
;
891 -- Nodes L and H must be side-effect-free expressions. If the input
892 -- aggregate N to Build_Loop contains no subaggregates, this routine
893 -- returns the while loop statement:
895 -- J : Index_Base := L;
897 -- J := Index_Base'Succ (J);
898 -- Into (Indexes, J) := Expr;
901 -- Otherwise we call Build_Code recursively
903 function Get_Assoc_Expr
(Assoc
: Node_Id
) return Node_Id
;
904 -- For an association with a box, use value given by aspect
905 -- Default_Component_Value of array type if specified, else use
906 -- value given by aspect Default_Value for component type itself
907 -- if specified, else return Empty.
909 function Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean;
910 function Local_Expr_Value
(E
: Node_Id
) return Uint
;
911 -- These two Local routines are used to replace the corresponding ones
912 -- in sem_eval because while processing the bounds of an aggregate with
913 -- discrete choices whose index type is an enumeration, we build static
914 -- expressions not recognized by Compile_Time_Known_Value as such since
915 -- they have not yet been analyzed and resolved. All the expressions in
916 -- question are things like Index_Base_Name'Val (Const) which we can
917 -- easily recognize as being constant.
923 function Add
(Val
: Int
; To
: Node_Id
) return Node_Id
is
928 U_Val
: constant Uint
:= UI_From_Int
(Val
);
931 -- Note: do not try to optimize the case of Val = 0, because
932 -- we need to build a new node with the proper Sloc value anyway.
934 -- First test if we can do constant folding
936 if Local_Compile_Time_Known_Value
(To
) then
937 U_To
:= Local_Expr_Value
(To
) + Val
;
939 -- Determine if our constant is outside the range of the index.
940 -- If so return an Empty node. This empty node will be caught
941 -- by Empty_Range below.
943 if Compile_Time_Known_Value
(Index_Base_L
)
944 and then U_To
< Expr_Value
(Index_Base_L
)
948 elsif Compile_Time_Known_Value
(Index_Base_H
)
949 and then U_To
> Expr_Value
(Index_Base_H
)
954 Expr_Pos
:= Make_Integer_Literal
(Loc
, U_To
);
955 Set_Is_Static_Expression
(Expr_Pos
);
957 if not Is_Enumeration_Type
(Index_Base
) then
960 -- If we are dealing with enumeration return
961 -- Index_Base'Val (Expr_Pos)
965 Make_Attribute_Reference
967 Prefix
=> Index_Base_Name
,
968 Attribute_Name
=> Name_Val
,
969 Expressions
=> New_List
(Expr_Pos
));
975 -- If we are here no constant folding possible
977 if not Is_Enumeration_Type
(Index_Base
) then
980 Left_Opnd
=> Duplicate_Subexpr
(To
),
981 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
983 -- If we are dealing with enumeration return
984 -- Index_Base'Val (Index_Base'Pos (To) + Val)
988 Make_Attribute_Reference
990 Prefix
=> Index_Base_Name
,
991 Attribute_Name
=> Name_Pos
,
992 Expressions
=> New_List
(Duplicate_Subexpr
(To
)));
997 Right_Opnd
=> Make_Integer_Literal
(Loc
, U_Val
));
1000 Make_Attribute_Reference
1002 Prefix
=> Index_Base_Name
,
1003 Attribute_Name
=> Name_Val
,
1004 Expressions
=> New_List
(Expr_Pos
));
1014 function Empty_Range
(L
, H
: Node_Id
) return Boolean is
1015 Is_Empty
: Boolean := False;
1020 -- First check if L or H were already detected as overflowing the
1021 -- index base range type by function Add above. If this is so Add
1022 -- returns the empty node.
1024 if No
(L
) or else No
(H
) then
1028 for J
in 1 .. 3 loop
1031 -- L > H range is empty
1037 -- B_L > H range must be empty
1040 Low
:= Index_Base_L
;
1043 -- L > B_H range must be empty
1047 High
:= Index_Base_H
;
1050 if Local_Compile_Time_Known_Value
(Low
)
1052 Local_Compile_Time_Known_Value
(High
)
1055 UI_Gt
(Local_Expr_Value
(Low
), Local_Expr_Value
(High
));
1068 function Equal
(L
, H
: Node_Id
) return Boolean is
1073 elsif Local_Compile_Time_Known_Value
(L
)
1075 Local_Compile_Time_Known_Value
(H
)
1077 return UI_Eq
(Local_Expr_Value
(L
), Local_Expr_Value
(H
));
1090 In_Loop
: Boolean := False) return List_Id
1092 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
;
1093 -- Collect insert_actions generated in the construction of a loop,
1094 -- and prepend them to the sequence of assignments to complete the
1095 -- eventual body of the loop.
1097 procedure Initialize_Array_Component
1098 (Arr_Comp
: Node_Id
;
1100 Init_Expr
: Node_Id
;
1102 -- Perform the initialization of array component Arr_Comp with
1103 -- expected type Comp_Typ. Init_Expr denotes the initialization
1104 -- expression of the array component. All generated code is added
1107 procedure Initialize_Ctrl_Array_Component
1108 (Arr_Comp
: Node_Id
;
1109 Comp_Typ
: Entity_Id
;
1110 Init_Expr
: Node_Id
;
1112 -- Perform the initialization of array component Arr_Comp when its
1113 -- expected type Comp_Typ needs finalization actions. Init_Expr is
1114 -- the initialization expression of the array component. All hook-
1115 -- related declarations are inserted prior to aggregate N. Remaining
1116 -- code is added to list Stmts.
1118 ----------------------
1119 -- Add_Loop_Actions --
1120 ----------------------
1122 function Add_Loop_Actions
(Lis
: List_Id
) return List_Id
is
1126 -- Ada 2005 (AI-287): Do nothing else in case of default
1127 -- initialized component.
1132 elsif Nkind
(Parent
(Expr
)) = N_Component_Association
1133 and then Present
(Loop_Actions
(Parent
(Expr
)))
1135 Append_List
(Lis
, Loop_Actions
(Parent
(Expr
)));
1136 Res
:= Loop_Actions
(Parent
(Expr
));
1137 Set_Loop_Actions
(Parent
(Expr
), No_List
);
1143 end Add_Loop_Actions
;
1145 --------------------------------
1146 -- Initialize_Array_Component --
1147 --------------------------------
1149 procedure Initialize_Array_Component
1150 (Arr_Comp
: Node_Id
;
1152 Init_Expr
: Node_Id
;
1155 Exceptions_OK
: constant Boolean :=
1156 not Restriction_Active
1157 (No_Exception_Propagation
);
1159 Finalization_OK
: constant Boolean :=
1161 and then Needs_Finalization
(Comp_Typ
);
1163 Full_Typ
: constant Entity_Id
:= Underlying_Type
(Comp_Typ
);
1165 Blk_Stmts
: List_Id
;
1166 Init_Stmt
: Node_Id
;
1169 -- Protect the initialization statements from aborts. Generate:
1173 if Finalization_OK
and Abort_Allowed
then
1174 if Exceptions_OK
then
1175 Blk_Stmts
:= New_List
;
1180 Append_To
(Blk_Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
1182 -- Otherwise aborts are not allowed. All generated code is added
1183 -- directly to the input list.
1189 -- Initialize the array element. Generate:
1191 -- Arr_Comp := Init_Expr;
1193 -- Note that the initialization expression is replicated because
1194 -- it has to be reevaluated within a generated loop.
1197 Make_OK_Assignment_Statement
(Loc
,
1198 Name
=> New_Copy_Tree
(Arr_Comp
),
1199 Expression
=> New_Copy_Tree
(Init_Expr
));
1200 Set_No_Ctrl_Actions
(Init_Stmt
);
1202 -- If this is an aggregate for an array of arrays, each
1203 -- subaggregate will be expanded as well, and even with
1204 -- No_Ctrl_Actions the assignments of inner components will
1205 -- require attachment in their assignments to temporaries. These
1206 -- temporaries must be finalized for each subaggregate. Generate:
1209 -- Arr_Comp := Init_Expr;
1212 if Finalization_OK
and then Is_Array_Type
(Comp_Typ
) then
1214 Make_Block_Statement
(Loc
,
1215 Handled_Statement_Sequence
=>
1216 Make_Handled_Sequence_Of_Statements
(Loc
,
1217 Statements
=> New_List
(Init_Stmt
)));
1220 Append_To
(Blk_Stmts
, Init_Stmt
);
1222 -- Adjust the tag due to a possible view conversion. Generate:
1224 -- Arr_Comp._tag := Full_TypP;
1226 if Tagged_Type_Expansion
1227 and then Present
(Comp_Typ
)
1228 and then Is_Tagged_Type
(Comp_Typ
)
1230 Append_To
(Blk_Stmts
,
1231 Make_OK_Assignment_Statement
(Loc
,
1233 Make_Selected_Component
(Loc
,
1234 Prefix
=> New_Copy_Tree
(Arr_Comp
),
1237 (First_Tag_Component
(Full_Typ
), Loc
)),
1240 Unchecked_Convert_To
(RTE
(RE_Tag
),
1242 (Node
(First_Elmt
(Access_Disp_Table
(Full_Typ
))),
1246 -- Adjust the array component. Controlled subaggregates are not
1247 -- considered because each of their individual elements will
1248 -- receive an adjustment of its own. Generate:
1250 -- [Deep_]Adjust (Arr_Comp);
1253 and then not Is_Limited_Type
(Comp_Typ
)
1254 and then not Is_Build_In_Place_Function_Call
(Init_Expr
)
1256 (Is_Array_Type
(Comp_Typ
)
1257 and then Is_Controlled
(Component_Type
(Comp_Typ
))
1258 and then Nkind
(Expr
) = N_Aggregate
)
1262 (Obj_Ref
=> New_Copy_Tree
(Arr_Comp
),
1265 -- Guard against a missing [Deep_]Adjust when the component
1266 -- type was not frozen properly.
1268 if Present
(Adj_Call
) then
1269 Append_To
(Blk_Stmts
, Adj_Call
);
1273 -- Complete the protection of the initialization statements
1275 if Finalization_OK
and Abort_Allowed
then
1277 -- Wrap the initialization statements in a block to catch a
1278 -- potential exception. Generate:
1282 -- Arr_Comp := Init_Expr;
1283 -- Arr_Comp._tag := Full_TypP;
1284 -- [Deep_]Adjust (Arr_Comp);
1286 -- Abort_Undefer_Direct;
1289 if Exceptions_OK
then
1291 Build_Abort_Undefer_Block
(Loc
,
1295 -- Otherwise exceptions are not propagated. Generate:
1298 -- Arr_Comp := Init_Expr;
1299 -- Arr_Comp._tag := Full_TypP;
1300 -- [Deep_]Adjust (Arr_Comp);
1304 Append_To
(Blk_Stmts
,
1305 Build_Runtime_Call
(Loc
, RE_Abort_Undefer
));
1308 end Initialize_Array_Component
;
1310 -------------------------------------
1311 -- Initialize_Ctrl_Array_Component --
1312 -------------------------------------
1314 procedure Initialize_Ctrl_Array_Component
1315 (Arr_Comp
: Node_Id
;
1316 Comp_Typ
: Entity_Id
;
1317 Init_Expr
: Node_Id
;
1321 Act_Stmts
: List_Id
;
1324 Hook_Clear
: Node_Id
;
1326 In_Place_Expansion
: Boolean;
1327 -- Flag set when a nonlimited controlled function call requires
1328 -- in-place expansion.
1331 -- Duplicate the initialization expression in case the context is
1332 -- a multi choice list or an "others" choice which plugs various
1333 -- holes in the aggregate. As a result the expression is no longer
1334 -- shared between the various components and is reevaluated for
1335 -- each such component.
1337 Expr
:= New_Copy_Tree
(Init_Expr
);
1338 Set_Parent
(Expr
, Parent
(Init_Expr
));
1340 -- Perform a preliminary analysis and resolution to determine what
1341 -- the initialization expression denotes. An unanalyzed function
1342 -- call may appear as an identifier or an indexed component.
1344 if Nkind_In
(Expr
, N_Function_Call
,
1346 N_Indexed_Component
)
1347 and then not Analyzed
(Expr
)
1349 Preanalyze_And_Resolve
(Expr
, Comp_Typ
);
1352 In_Place_Expansion
:=
1353 Nkind
(Expr
) = N_Function_Call
1354 and then not Is_Build_In_Place_Result_Type
(Comp_Typ
);
1356 -- The initialization expression is a controlled function call.
1357 -- Perform in-place removal of side effects to avoid creating a
1358 -- transient scope, which leads to premature finalization.
1360 -- This in-place expansion is not performed for limited transient
1361 -- objects because the initialization is already done in-place.
1363 if In_Place_Expansion
then
1365 -- Suppress the removal of side effects by general analysis
1366 -- because this behavior is emulated here. This avoids the
1367 -- generation of a transient scope, which leads to out-of-order
1368 -- adjustment and finalization.
1370 Set_No_Side_Effect_Removal
(Expr
);
1372 -- When the transient component initialization is related to a
1373 -- range or an "others", keep all generated statements within
1374 -- the enclosing loop. This way the controlled function call
1375 -- will be evaluated at each iteration, and its result will be
1376 -- finalized at the end of each iteration.
1382 -- Otherwise this is a single component initialization. Hook-
1383 -- related statements are inserted prior to the aggregate.
1387 Act_Stmts
:= No_List
;
1390 -- Install all hook-related declarations and prepare the clean
1393 Process_Transient_Component
1395 Comp_Typ
=> Comp_Typ
,
1397 Fin_Call
=> Fin_Call
,
1398 Hook_Clear
=> Hook_Clear
,
1400 Stmts
=> Act_Stmts
);
1403 -- Use the noncontrolled component initialization circuitry to
1404 -- assign the result of the function call to the array element.
1405 -- This also performs subaggregate wrapping, tag adjustment, and
1406 -- [deep] adjustment of the array element.
1408 Initialize_Array_Component
1409 (Arr_Comp
=> Arr_Comp
,
1410 Comp_Typ
=> Comp_Typ
,
1414 -- At this point the array element is fully initialized. Complete
1415 -- the processing of the controlled array component by finalizing
1416 -- the transient function result.
1418 if In_Place_Expansion
then
1419 Process_Transient_Component_Completion
1422 Fin_Call
=> Fin_Call
,
1423 Hook_Clear
=> Hook_Clear
,
1426 end Initialize_Ctrl_Array_Component
;
1430 Stmts
: constant List_Id
:= New_List
;
1432 Comp_Typ
: Entity_Id
:= Empty
;
1434 Indexed_Comp
: Node_Id
;
1435 Init_Call
: Node_Id
;
1436 New_Indexes
: List_Id
;
1438 -- Start of processing for Gen_Assign
1441 if No
(Indexes
) then
1442 New_Indexes
:= New_List
;
1444 New_Indexes
:= New_Copy_List_Tree
(Indexes
);
1447 Append_To
(New_Indexes
, Ind
);
1449 if Present
(Next_Index
(Index
)) then
1452 Build_Array_Aggr_Code
1455 Index
=> Next_Index
(Index
),
1457 Scalar_Comp
=> Scalar_Comp
,
1458 Indexes
=> New_Indexes
));
1461 -- If we get here then we are at a bottom-level (sub-)aggregate
1465 (Make_Indexed_Component
(Loc
,
1466 Prefix
=> New_Copy_Tree
(Into
),
1467 Expressions
=> New_Indexes
));
1469 Set_Assignment_OK
(Indexed_Comp
);
1471 -- Ada 2005 (AI-287): In case of default initialized component, Expr
1472 -- is not present (and therefore we also initialize Expr_Q to empty).
1476 elsif Nkind
(Expr
) = N_Qualified_Expression
then
1477 Expr_Q
:= Expression
(Expr
);
1482 if Present
(Etype
(N
)) and then Etype
(N
) /= Any_Composite
then
1483 Comp_Typ
:= Component_Type
(Etype
(N
));
1484 pragma Assert
(Comp_Typ
= Ctype
); -- AI-287
1486 elsif Present
(Next
(First
(New_Indexes
))) then
1488 -- Ada 2005 (AI-287): Do nothing in case of default initialized
1489 -- component because we have received the component type in
1490 -- the formal parameter Ctype.
1492 -- ??? Some assert pragmas have been added to check if this new
1493 -- formal can be used to replace this code in all cases.
1495 if Present
(Expr
) then
1497 -- This is a multidimensional array. Recover the component type
1498 -- from the outermost aggregate, because subaggregates do not
1499 -- have an assigned type.
1506 while Present
(P
) loop
1507 if Nkind
(P
) = N_Aggregate
1508 and then Present
(Etype
(P
))
1510 Comp_Typ
:= Component_Type
(Etype
(P
));
1518 pragma Assert
(Comp_Typ
= Ctype
); -- AI-287
1523 -- Ada 2005 (AI-287): We only analyze the expression in case of non-
1524 -- default initialized components (otherwise Expr_Q is not present).
1527 and then Nkind_In
(Expr_Q
, N_Aggregate
, N_Extension_Aggregate
)
1529 -- At this stage the Expression may not have been analyzed yet
1530 -- because the array aggregate code has not been updated to use
1531 -- the Expansion_Delayed flag and avoid analysis altogether to
1532 -- solve the same problem (see Resolve_Aggr_Expr). So let us do
1533 -- the analysis of non-array aggregates now in order to get the
1534 -- value of Expansion_Delayed flag for the inner aggregate ???
1536 -- In the case of an iterated component association, the analysis
1537 -- of the generated loop will analyze the expression in the
1538 -- proper context, in which the loop parameter is visible.
1540 if Present
(Comp_Typ
) and then not Is_Array_Type
(Comp_Typ
)
1542 Nkind
(Parent
(Expr_Q
)) /= N_Iterated_Component_Association
1544 Analyze_And_Resolve
(Expr_Q
, Comp_Typ
);
1547 if Is_Delayed_Aggregate
(Expr_Q
) then
1549 -- This is either a subaggregate of a multidimensional array,
1550 -- or a component of an array type whose component type is
1551 -- also an array. In the latter case, the expression may have
1552 -- component associations that provide different bounds from
1553 -- those of the component type, and sliding must occur. Instead
1554 -- of decomposing the current aggregate assignment, force the
1555 -- reanalysis of the assignment, so that a temporary will be
1556 -- generated in the usual fashion, and sliding will take place.
1558 if Nkind
(Parent
(N
)) = N_Assignment_Statement
1559 and then Is_Array_Type
(Comp_Typ
)
1560 and then Present
(Component_Associations
(Expr_Q
))
1561 and then Must_Slide
(Comp_Typ
, Etype
(Expr_Q
))
1563 Set_Expansion_Delayed
(Expr_Q
, False);
1564 Set_Analyzed
(Expr_Q
, False);
1569 Late_Expansion
(Expr_Q
, Etype
(Expr_Q
), Indexed_Comp
));
1574 if Present
(Expr
) then
1576 -- Handle an initialization expression of a controlled type in
1577 -- case it denotes a function call. In general such a scenario
1578 -- will produce a transient scope, but this will lead to wrong
1579 -- order of initialization, adjustment, and finalization in the
1580 -- context of aggregates.
1582 -- Target (1) := Ctrl_Func_Call;
1585 -- Trans_Obj : ... := Ctrl_Func_Call; -- object
1586 -- Target (1) := Trans_Obj;
1587 -- Finalize (Trans_Obj);
1589 -- Target (1)._tag := ...;
1590 -- Adjust (Target (1));
1592 -- In the example above, the call to Finalize occurs too early
1593 -- and as a result it may leave the array component in a bad
1594 -- state. Finalization of the transient object should really
1595 -- happen after adjustment.
1597 -- To avoid this scenario, perform in-place side-effect removal
1598 -- of the function call. This eliminates the transient property
1599 -- of the function result and ensures correct order of actions.
1601 -- Res : ... := Ctrl_Func_Call;
1602 -- Target (1) := Res;
1603 -- Target (1)._tag := ...;
1604 -- Adjust (Target (1));
1607 if Present
(Comp_Typ
)
1608 and then Needs_Finalization
(Comp_Typ
)
1609 and then Nkind
(Expr
) /= N_Aggregate
1611 Initialize_Ctrl_Array_Component
1612 (Arr_Comp
=> Indexed_Comp
,
1613 Comp_Typ
=> Comp_Typ
,
1617 -- Otherwise perform simple component initialization
1620 Initialize_Array_Component
1621 (Arr_Comp
=> Indexed_Comp
,
1622 Comp_Typ
=> Comp_Typ
,
1627 -- Ada 2005 (AI-287): In case of default initialized component, call
1628 -- the initialization subprogram associated with the component type.
1629 -- If the component type is an access type, add an explicit null
1630 -- assignment, because for the back-end there is an initialization
1631 -- present for the whole aggregate, and no default initialization
1634 -- In addition, if the component type is controlled, we must call
1635 -- its Initialize procedure explicitly, because there is no explicit
1636 -- object creation that will invoke it otherwise.
1639 if Present
(Base_Init_Proc
(Base_Type
(Ctype
)))
1640 or else Has_Task
(Base_Type
(Ctype
))
1642 Append_List_To
(Stmts
,
1643 Build_Initialization_Call
(Loc
,
1644 Id_Ref
=> Indexed_Comp
,
1646 With_Default_Init
=> True));
1648 -- If the component type has invariants, add an invariant
1649 -- check after the component is default-initialized. It will
1650 -- be analyzed and resolved before the code for initialization
1651 -- of other components.
1653 if Has_Invariants
(Ctype
) then
1654 Set_Etype
(Indexed_Comp
, Ctype
);
1655 Append_To
(Stmts
, Make_Invariant_Call
(Indexed_Comp
));
1658 elsif Is_Access_Type
(Ctype
) then
1660 Make_Assignment_Statement
(Loc
,
1661 Name
=> New_Copy_Tree
(Indexed_Comp
),
1662 Expression
=> Make_Null
(Loc
)));
1665 if Needs_Finalization
(Ctype
) then
1668 (Obj_Ref
=> New_Copy_Tree
(Indexed_Comp
),
1671 -- Guard against a missing [Deep_]Initialize when the component
1672 -- type was not properly frozen.
1674 if Present
(Init_Call
) then
1675 Append_To
(Stmts
, Init_Call
);
1680 return Add_Loop_Actions
(Stmts
);
1687 function Gen_Loop
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1688 Is_Iterated_Component
: constant Boolean :=
1689 Nkind
(Parent
(Expr
)) = N_Iterated_Component_Association
;
1700 -- Index_Base'(L) .. Index_Base'(H)
1702 L_Iteration_Scheme
: Node_Id
;
1703 -- L_J in Index_Base'(L) .. Index_Base'(H)
1706 -- The statements to execute in the loop
1708 S
: constant List_Id
:= New_List
;
1709 -- List of statements
1712 -- Copy of expression tree, used for checking purposes
1715 -- If loop bounds define an empty range return the null statement
1717 if Empty_Range
(L
, H
) then
1718 Append_To
(S
, Make_Null_Statement
(Loc
));
1720 -- Ada 2005 (AI-287): Nothing else need to be done in case of
1721 -- default initialized component.
1727 -- The expression must be type-checked even though no component
1728 -- of the aggregate will have this value. This is done only for
1729 -- actual components of the array, not for subaggregates. Do
1730 -- the check on a copy, because the expression may be shared
1731 -- among several choices, some of which might be non-null.
1733 if Present
(Etype
(N
))
1734 and then Is_Array_Type
(Etype
(N
))
1735 and then No
(Next_Index
(Index
))
1737 Expander_Mode_Save_And_Set
(False);
1738 Tcopy
:= New_Copy_Tree
(Expr
);
1739 Set_Parent
(Tcopy
, N
);
1740 Analyze_And_Resolve
(Tcopy
, Component_Type
(Etype
(N
)));
1741 Expander_Mode_Restore
;
1747 -- If loop bounds are the same then generate an assignment, unless
1748 -- the parent construct is an Iterated_Component_Association.
1750 elsif Equal
(L
, H
) and then not Is_Iterated_Component
then
1751 return Gen_Assign
(New_Copy_Tree
(L
), Expr
);
1753 -- If H - L <= 2 then generate a sequence of assignments when we are
1754 -- processing the bottom most aggregate and it contains scalar
1757 elsif No
(Next_Index
(Index
))
1758 and then Scalar_Comp
1759 and then Local_Compile_Time_Known_Value
(L
)
1760 and then Local_Compile_Time_Known_Value
(H
)
1761 and then Local_Expr_Value
(H
) - Local_Expr_Value
(L
) <= 2
1762 and then not Is_Iterated_Component
1764 Append_List_To
(S
, Gen_Assign
(New_Copy_Tree
(L
), Expr
));
1765 Append_List_To
(S
, Gen_Assign
(Add
(1, To
=> L
), Expr
));
1767 if Local_Expr_Value
(H
) - Local_Expr_Value
(L
) = 2 then
1768 Append_List_To
(S
, Gen_Assign
(Add
(2, To
=> L
), Expr
));
1774 -- Otherwise construct the loop, starting with the loop index L_J
1776 if Is_Iterated_Component
then
1778 Make_Defining_Identifier
(Loc
,
1779 Chars
=> (Chars
(Defining_Identifier
(Parent
(Expr
)))));
1782 L_J
:= Make_Temporary
(Loc
, 'J', L
);
1785 -- Construct "L .. H" in Index_Base. We use a qualified expression
1786 -- for the bound to convert to the index base, but we don't need
1787 -- to do that if we already have the base type at hand.
1789 if Etype
(L
) = Index_Base
then
1793 Make_Qualified_Expression
(Loc
,
1794 Subtype_Mark
=> Index_Base_Name
,
1795 Expression
=> New_Copy_Tree
(L
));
1798 if Etype
(H
) = Index_Base
then
1802 Make_Qualified_Expression
(Loc
,
1803 Subtype_Mark
=> Index_Base_Name
,
1804 Expression
=> New_Copy_Tree
(H
));
1812 -- Construct "for L_J in Index_Base range L .. H"
1814 L_Iteration_Scheme
:=
1815 Make_Iteration_Scheme
1817 Loop_Parameter_Specification
=>
1818 Make_Loop_Parameter_Specification
1820 Defining_Identifier
=> L_J
,
1821 Discrete_Subtype_Definition
=> L_Range
));
1823 -- Construct the statements to execute in the loop body
1826 Gen_Assign
(New_Occurrence_Of
(L_J
, Loc
), Expr
, In_Loop
=> True);
1828 -- Construct the final loop
1831 Make_Implicit_Loop_Statement
1833 Identifier
=> Empty
,
1834 Iteration_Scheme
=> L_Iteration_Scheme
,
1835 Statements
=> L_Body
));
1837 -- A small optimization: if the aggregate is initialized with a box
1838 -- and the component type has no initialization procedure, remove the
1839 -- useless empty loop.
1841 if Nkind
(First
(S
)) = N_Loop_Statement
1842 and then Is_Empty_List
(Statements
(First
(S
)))
1844 return New_List
(Make_Null_Statement
(Loc
));
1854 -- The code built is
1856 -- W_J : Index_Base := L;
1857 -- while W_J < H loop
1858 -- W_J := Index_Base'Succ (W);
1862 function Gen_While
(L
, H
: Node_Id
; Expr
: Node_Id
) return List_Id
is
1866 -- W_J : Base_Type := L;
1868 W_Iteration_Scheme
: Node_Id
;
1871 W_Index_Succ
: Node_Id
;
1872 -- Index_Base'Succ (J)
1874 W_Increment
: Node_Id
;
1875 -- W_J := Index_Base'Succ (W)
1877 W_Body
: constant List_Id
:= New_List
;
1878 -- The statements to execute in the loop
1880 S
: constant List_Id
:= New_List
;
1881 -- list of statement
1884 -- If loop bounds define an empty range or are equal return null
1886 if Empty_Range
(L
, H
) or else Equal
(L
, H
) then
1887 Append_To
(S
, Make_Null_Statement
(Loc
));
1891 -- Build the decl of W_J
1893 W_J
:= Make_Temporary
(Loc
, 'J', L
);
1895 Make_Object_Declaration
1897 Defining_Identifier
=> W_J
,
1898 Object_Definition
=> Index_Base_Name
,
1901 -- Theoretically we should do a New_Copy_Tree (L) here, but we know
1902 -- that in this particular case L is a fresh Expr generated by
1903 -- Add which we are the only ones to use.
1905 Append_To
(S
, W_Decl
);
1907 -- Construct " while W_J < H"
1909 W_Iteration_Scheme
:=
1910 Make_Iteration_Scheme
1912 Condition
=> Make_Op_Lt
1914 Left_Opnd
=> New_Occurrence_Of
(W_J
, Loc
),
1915 Right_Opnd
=> New_Copy_Tree
(H
)));
1917 -- Construct the statements to execute in the loop body
1920 Make_Attribute_Reference
1922 Prefix
=> Index_Base_Name
,
1923 Attribute_Name
=> Name_Succ
,
1924 Expressions
=> New_List
(New_Occurrence_Of
(W_J
, Loc
)));
1927 Make_OK_Assignment_Statement
1929 Name
=> New_Occurrence_Of
(W_J
, Loc
),
1930 Expression
=> W_Index_Succ
);
1932 Append_To
(W_Body
, W_Increment
);
1934 Append_List_To
(W_Body
,
1935 Gen_Assign
(New_Occurrence_Of
(W_J
, Loc
), Expr
, In_Loop
=> True));
1937 -- Construct the final loop
1940 Make_Implicit_Loop_Statement
1942 Identifier
=> Empty
,
1943 Iteration_Scheme
=> W_Iteration_Scheme
,
1944 Statements
=> W_Body
));
1949 --------------------
1950 -- Get_Assoc_Expr --
1951 --------------------
1953 function Get_Assoc_Expr
(Assoc
: Node_Id
) return Node_Id
is
1954 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
1957 if Box_Present
(Assoc
) then
1958 if Is_Scalar_Type
(Ctype
) then
1959 if Present
(Default_Aspect_Component_Value
(Typ
)) then
1960 return Default_Aspect_Component_Value
(Typ
);
1961 elsif Present
(Default_Aspect_Value
(Ctype
)) then
1962 return Default_Aspect_Value
(Ctype
);
1972 return Expression
(Assoc
);
1976 ---------------------
1977 -- Index_Base_Name --
1978 ---------------------
1980 function Index_Base_Name
return Node_Id
is
1982 return New_Occurrence_Of
(Index_Base
, Sloc
(N
));
1983 end Index_Base_Name
;
1985 ------------------------------------
1986 -- Local_Compile_Time_Known_Value --
1987 ------------------------------------
1989 function Local_Compile_Time_Known_Value
(E
: Node_Id
) return Boolean is
1991 return Compile_Time_Known_Value
(E
)
1993 (Nkind
(E
) = N_Attribute_Reference
1994 and then Attribute_Name
(E
) = Name_Val
1995 and then Compile_Time_Known_Value
(First
(Expressions
(E
))));
1996 end Local_Compile_Time_Known_Value
;
1998 ----------------------
1999 -- Local_Expr_Value --
2000 ----------------------
2002 function Local_Expr_Value
(E
: Node_Id
) return Uint
is
2004 if Compile_Time_Known_Value
(E
) then
2005 return Expr_Value
(E
);
2007 return Expr_Value
(First
(Expressions
(E
)));
2009 end Local_Expr_Value
;
2013 New_Code
: constant List_Id
:= New_List
;
2015 Aggr_L
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(N
));
2016 Aggr_H
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(N
));
2017 -- The aggregate bounds of this specific subaggregate. Note that if the
2018 -- code generated by Build_Array_Aggr_Code is executed then these bounds
2019 -- are OK. Otherwise a Constraint_Error would have been raised.
2021 Aggr_Low
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_L
);
2022 Aggr_High
: constant Node_Id
:= Duplicate_Subexpr_No_Checks
(Aggr_H
);
2023 -- After Duplicate_Subexpr these are side-effect free
2032 Nb_Choices
: Nat
:= 0;
2033 Table
: Case_Table_Type
(1 .. Number_Of_Choices
(N
));
2034 -- Used to sort all the different choice values
2037 -- Number of elements in the positional aggregate
2039 Others_Assoc
: Node_Id
:= Empty
;
2041 -- Start of processing for Build_Array_Aggr_Code
2044 -- First before we start, a special case. if we have a bit packed
2045 -- array represented as a modular type, then clear the value to
2046 -- zero first, to ensure that unused bits are properly cleared.
2051 and then Is_Bit_Packed_Array
(Typ
)
2052 and then Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
))
2054 Append_To
(New_Code
,
2055 Make_Assignment_Statement
(Loc
,
2056 Name
=> New_Copy_Tree
(Into
),
2058 Unchecked_Convert_To
(Typ
,
2059 Make_Integer_Literal
(Loc
, Uint_0
))));
2062 -- If the component type contains tasks, we need to build a Master
2063 -- entity in the current scope, because it will be needed if build-
2064 -- in-place functions are called in the expanded code.
2066 if Nkind
(Parent
(N
)) = N_Object_Declaration
and then Has_Task
(Typ
) then
2067 Build_Master_Entity
(Defining_Identifier
(Parent
(N
)));
2070 -- STEP 1: Process component associations
2072 -- For those associations that may generate a loop, initialize
2073 -- Loop_Actions to collect inserted actions that may be crated.
2075 -- Skip this if no component associations
2077 if No
(Expressions
(N
)) then
2079 -- STEP 1 (a): Sort the discrete choices
2081 Assoc
:= First
(Component_Associations
(N
));
2082 while Present
(Assoc
) loop
2083 Choice
:= First
(Choice_List
(Assoc
));
2084 while Present
(Choice
) loop
2085 if Nkind
(Choice
) = N_Others_Choice
then
2086 Set_Loop_Actions
(Assoc
, New_List
);
2087 Others_Assoc
:= Assoc
;
2091 Get_Index_Bounds
(Choice
, Low
, High
);
2094 Set_Loop_Actions
(Assoc
, New_List
);
2097 Nb_Choices
:= Nb_Choices
+ 1;
2099 Table
(Nb_Choices
) :=
2102 Choice_Node
=> Get_Assoc_Expr
(Assoc
));
2110 -- If there is more than one set of choices these must be static
2111 -- and we can therefore sort them. Remember that Nb_Choices does not
2112 -- account for an others choice.
2114 if Nb_Choices
> 1 then
2115 Sort_Case_Table
(Table
);
2118 -- STEP 1 (b): take care of the whole set of discrete choices
2120 for J
in 1 .. Nb_Choices
loop
2121 Low
:= Table
(J
).Choice_Lo
;
2122 High
:= Table
(J
).Choice_Hi
;
2123 Expr
:= Table
(J
).Choice_Node
;
2124 Append_List
(Gen_Loop
(Low
, High
, Expr
), To
=> New_Code
);
2127 -- STEP 1 (c): generate the remaining loops to cover others choice
2128 -- We don't need to generate loops over empty gaps, but if there is
2129 -- a single empty range we must analyze the expression for semantics
2131 if Present
(Others_Assoc
) then
2133 First
: Boolean := True;
2136 for J
in 0 .. Nb_Choices
loop
2140 Low
:= Add
(1, To
=> Table
(J
).Choice_Hi
);
2143 if J
= Nb_Choices
then
2146 High
:= Add
(-1, To
=> Table
(J
+ 1).Choice_Lo
);
2149 -- If this is an expansion within an init proc, make
2150 -- sure that discriminant references are replaced by
2151 -- the corresponding discriminal.
2153 if Inside_Init_Proc
then
2154 if Is_Entity_Name
(Low
)
2155 and then Ekind
(Entity
(Low
)) = E_Discriminant
2157 Set_Entity
(Low
, Discriminal
(Entity
(Low
)));
2160 if Is_Entity_Name
(High
)
2161 and then Ekind
(Entity
(High
)) = E_Discriminant
2163 Set_Entity
(High
, Discriminal
(Entity
(High
)));
2168 or else not Empty_Range
(Low
, High
)
2172 (Gen_Loop
(Low
, High
,
2173 Get_Assoc_Expr
(Others_Assoc
)), To
=> New_Code
);
2179 -- STEP 2: Process positional components
2182 -- STEP 2 (a): Generate the assignments for each positional element
2183 -- Note that here we have to use Aggr_L rather than Aggr_Low because
2184 -- Aggr_L is analyzed and Add wants an analyzed expression.
2186 Expr
:= First
(Expressions
(N
));
2188 while Present
(Expr
) loop
2189 Nb_Elements
:= Nb_Elements
+ 1;
2190 Append_List
(Gen_Assign
(Add
(Nb_Elements
, To
=> Aggr_L
), Expr
),
2195 -- STEP 2 (b): Generate final loop if an others choice is present
2196 -- Here Nb_Elements gives the offset of the last positional element.
2198 if Present
(Component_Associations
(N
)) then
2199 Assoc
:= Last
(Component_Associations
(N
));
2201 -- Ada 2005 (AI-287)
2203 Append_List
(Gen_While
(Add
(Nb_Elements
, To
=> Aggr_L
),
2205 Get_Assoc_Expr
(Assoc
)), -- AI-287
2211 end Build_Array_Aggr_Code
;
2213 ----------------------------
2214 -- Build_Record_Aggr_Code --
2215 ----------------------------
2217 function Build_Record_Aggr_Code
2220 Lhs
: Node_Id
) return List_Id
2222 Loc
: constant Source_Ptr
:= Sloc
(N
);
2223 L
: constant List_Id
:= New_List
;
2224 N_Typ
: constant Entity_Id
:= Etype
(N
);
2230 Comp_Type
: Entity_Id
;
2231 Selector
: Entity_Id
;
2232 Comp_Expr
: Node_Id
;
2235 -- If this is an internal aggregate, the External_Final_List is an
2236 -- expression for the controller record of the enclosing type.
2238 -- If the current aggregate has several controlled components, this
2239 -- expression will appear in several calls to attach to the finali-
2240 -- zation list, and it must not be shared.
2242 Ancestor_Is_Expression
: Boolean := False;
2243 Ancestor_Is_Subtype_Mark
: Boolean := False;
2245 Init_Typ
: Entity_Id
:= Empty
;
2247 Finalization_Done
: Boolean := False;
2248 -- True if Generate_Finalization_Actions has already been called; calls
2249 -- after the first do nothing.
2251 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
;
2252 -- Returns the value that the given discriminant of an ancestor type
2253 -- should receive (in the absence of a conflict with the value provided
2254 -- by an ancestor part of an extension aggregate).
2256 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
);
2257 -- Check that each of the discriminant values defined by the ancestor
2258 -- part of an extension aggregate match the corresponding values
2259 -- provided by either an association of the aggregate or by the
2260 -- constraint imposed by a parent type (RM95-4.3.2(8)).
2262 function Compatible_Int_Bounds
2263 (Agg_Bounds
: Node_Id
;
2264 Typ_Bounds
: Node_Id
) return Boolean;
2265 -- Return true if Agg_Bounds are equal or within Typ_Bounds. It is
2266 -- assumed that both bounds are integer ranges.
2268 procedure Generate_Finalization_Actions
;
2269 -- Deal with the various controlled type data structure initializations
2270 -- (but only if it hasn't been done already).
2272 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
;
2273 -- Returns the first discriminant association in the constraint
2274 -- associated with T, if any, otherwise returns Empty.
2276 function Get_Explicit_Discriminant_Value
(D
: Entity_Id
) return Node_Id
;
2277 -- If the ancestor part is an unconstrained type and further ancestors
2278 -- do not provide discriminants for it, check aggregate components for
2279 -- values of the discriminants.
2281 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
);
2282 -- If Typ is derived, and constrains discriminants of the parent type,
2283 -- these discriminants are not components of the aggregate, and must be
2284 -- initialized. The assignments are appended to List. The same is done
2285 -- if Typ derives fron an already constrained subtype of a discriminated
2288 procedure Init_Stored_Discriminants
;
2289 -- If the type is derived and has inherited discriminants, generate
2290 -- explicit assignments for each, using the store constraint of the
2291 -- type. Note that both visible and stored discriminants must be
2292 -- initialized in case the derived type has some renamed and some
2293 -- constrained discriminants.
2295 procedure Init_Visible_Discriminants
;
2296 -- If type has discriminants, retrieve their values from aggregate,
2297 -- and generate explicit assignments for each. This does not include
2298 -- discriminants inherited from ancestor, which are handled above.
2299 -- The type of the aggregate is a subtype created ealier using the
2300 -- given values of the discriminant components of the aggregate.
2302 procedure Initialize_Ctrl_Record_Component
2303 (Rec_Comp
: Node_Id
;
2304 Comp_Typ
: Entity_Id
;
2305 Init_Expr
: Node_Id
;
2307 -- Perform the initialization of controlled record component Rec_Comp.
2308 -- Comp_Typ is the component type. Init_Expr is the initialization
2309 -- expression for the record component. Hook-related declarations are
2310 -- inserted prior to aggregate N using Insert_Action. All remaining
2311 -- generated code is added to list Stmts.
2313 procedure Initialize_Record_Component
2314 (Rec_Comp
: Node_Id
;
2315 Comp_Typ
: Entity_Id
;
2316 Init_Expr
: Node_Id
;
2318 -- Perform the initialization of record component Rec_Comp. Comp_Typ
2319 -- is the component type. Init_Expr is the initialization expression
2320 -- of the record component. All generated code is added to list Stmts.
2322 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean;
2323 -- Check whether Bounds is a range node and its lower and higher bounds
2324 -- are integers literals.
2326 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
;
2327 -- If the aggregate contains a self-reference, traverse each expression
2328 -- to replace a possible self-reference with a reference to the proper
2329 -- component of the target of the assignment.
2331 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
;
2332 -- If default expression of a component mentions a discriminant of the
2333 -- type, it must be rewritten as the discriminant of the target object.
2335 ---------------------------------
2336 -- Ancestor_Discriminant_Value --
2337 ---------------------------------
2339 function Ancestor_Discriminant_Value
(Disc
: Entity_Id
) return Node_Id
is
2341 Assoc_Elmt
: Elmt_Id
;
2342 Aggr_Comp
: Entity_Id
;
2343 Corresp_Disc
: Entity_Id
;
2344 Current_Typ
: Entity_Id
:= Base_Type
(Typ
);
2345 Parent_Typ
: Entity_Id
;
2346 Parent_Disc
: Entity_Id
;
2347 Save_Assoc
: Node_Id
:= Empty
;
2350 -- First check any discriminant associations to see if any of them
2351 -- provide a value for the discriminant.
2353 if Present
(Discriminant_Specifications
(Parent
(Current_Typ
))) then
2354 Assoc
:= First
(Component_Associations
(N
));
2355 while Present
(Assoc
) loop
2356 Aggr_Comp
:= Entity
(First
(Choices
(Assoc
)));
2358 if Ekind
(Aggr_Comp
) = E_Discriminant
then
2359 Save_Assoc
:= Expression
(Assoc
);
2361 Corresp_Disc
:= Corresponding_Discriminant
(Aggr_Comp
);
2362 while Present
(Corresp_Disc
) loop
2364 -- If found a corresponding discriminant then return the
2365 -- value given in the aggregate. (Note: this is not
2366 -- correct in the presence of side effects. ???)
2368 if Disc
= Corresp_Disc
then
2369 return Duplicate_Subexpr
(Expression
(Assoc
));
2372 Corresp_Disc
:= Corresponding_Discriminant
(Corresp_Disc
);
2380 -- No match found in aggregate, so chain up parent types to find
2381 -- a constraint that defines the value of the discriminant.
2383 Parent_Typ
:= Etype
(Current_Typ
);
2384 while Current_Typ
/= Parent_Typ
loop
2385 if Has_Discriminants
(Parent_Typ
)
2386 and then not Has_Unknown_Discriminants
(Parent_Typ
)
2388 Parent_Disc
:= First_Discriminant
(Parent_Typ
);
2390 -- We either get the association from the subtype indication
2391 -- of the type definition itself, or from the discriminant
2392 -- constraint associated with the type entity (which is
2393 -- preferable, but it's not always present ???)
2395 if Is_Empty_Elmt_List
(Discriminant_Constraint
(Current_Typ
))
2397 Assoc
:= Get_Constraint_Association
(Current_Typ
);
2398 Assoc_Elmt
:= No_Elmt
;
2401 First_Elmt
(Discriminant_Constraint
(Current_Typ
));
2402 Assoc
:= Node
(Assoc_Elmt
);
2405 -- Traverse the discriminants of the parent type looking
2406 -- for one that corresponds.
2408 while Present
(Parent_Disc
) and then Present
(Assoc
) loop
2409 Corresp_Disc
:= Parent_Disc
;
2410 while Present
(Corresp_Disc
)
2411 and then Disc
/= Corresp_Disc
2413 Corresp_Disc
:= Corresponding_Discriminant
(Corresp_Disc
);
2416 if Disc
= Corresp_Disc
then
2417 if Nkind
(Assoc
) = N_Discriminant_Association
then
2418 Assoc
:= Expression
(Assoc
);
2421 -- If the located association directly denotes
2422 -- a discriminant, then use the value of a saved
2423 -- association of the aggregate. This is an approach
2424 -- used to handle certain cases involving multiple
2425 -- discriminants mapped to a single discriminant of
2426 -- a descendant. It's not clear how to locate the
2427 -- appropriate discriminant value for such cases. ???
2429 if Is_Entity_Name
(Assoc
)
2430 and then Ekind
(Entity
(Assoc
)) = E_Discriminant
2432 Assoc
:= Save_Assoc
;
2435 return Duplicate_Subexpr
(Assoc
);
2438 Next_Discriminant
(Parent_Disc
);
2440 if No
(Assoc_Elmt
) then
2444 Next_Elmt
(Assoc_Elmt
);
2446 if Present
(Assoc_Elmt
) then
2447 Assoc
:= Node
(Assoc_Elmt
);
2455 Current_Typ
:= Parent_Typ
;
2456 Parent_Typ
:= Etype
(Current_Typ
);
2459 -- In some cases there's no ancestor value to locate (such as
2460 -- when an ancestor part given by an expression defines the
2461 -- discriminant value).
2464 end Ancestor_Discriminant_Value
;
2466 ----------------------------------
2467 -- Check_Ancestor_Discriminants --
2468 ----------------------------------
2470 procedure Check_Ancestor_Discriminants
(Anc_Typ
: Entity_Id
) is
2472 Disc_Value
: Node_Id
;
2476 Discr
:= First_Discriminant
(Base_Type
(Anc_Typ
));
2477 while Present
(Discr
) loop
2478 Disc_Value
:= Ancestor_Discriminant_Value
(Discr
);
2480 if Present
(Disc_Value
) then
2481 Cond
:= Make_Op_Ne
(Loc
,
2483 Make_Selected_Component
(Loc
,
2484 Prefix
=> New_Copy_Tree
(Target
),
2485 Selector_Name
=> New_Occurrence_Of
(Discr
, Loc
)),
2486 Right_Opnd
=> Disc_Value
);
2489 Make_Raise_Constraint_Error
(Loc
,
2491 Reason
=> CE_Discriminant_Check_Failed
));
2494 Next_Discriminant
(Discr
);
2496 end Check_Ancestor_Discriminants
;
2498 ---------------------------
2499 -- Compatible_Int_Bounds --
2500 ---------------------------
2502 function Compatible_Int_Bounds
2503 (Agg_Bounds
: Node_Id
;
2504 Typ_Bounds
: Node_Id
) return Boolean
2506 Agg_Lo
: constant Uint
:= Intval
(Low_Bound
(Agg_Bounds
));
2507 Agg_Hi
: constant Uint
:= Intval
(High_Bound
(Agg_Bounds
));
2508 Typ_Lo
: constant Uint
:= Intval
(Low_Bound
(Typ_Bounds
));
2509 Typ_Hi
: constant Uint
:= Intval
(High_Bound
(Typ_Bounds
));
2511 return Typ_Lo
<= Agg_Lo
and then Agg_Hi
<= Typ_Hi
;
2512 end Compatible_Int_Bounds
;
2514 -----------------------------------
2515 -- Generate_Finalization_Actions --
2516 -----------------------------------
2518 procedure Generate_Finalization_Actions
is
2520 -- Do the work only the first time this is called
2522 if Finalization_Done
then
2526 Finalization_Done
:= True;
2528 -- Determine the external finalization list. It is either the
2529 -- finalization list of the outer scope or the one coming from an
2530 -- outer aggregate. When the target is not a temporary, the proper
2531 -- scope is the scope of the target rather than the potentially
2532 -- transient current scope.
2534 if Is_Controlled
(Typ
) and then Ancestor_Is_Subtype_Mark
then
2535 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
2536 Set_Assignment_OK
(Ref
);
2539 Make_Procedure_Call_Statement
(Loc
,
2542 (Find_Prim_Op
(Init_Typ
, Name_Initialize
), Loc
),
2543 Parameter_Associations
=> New_List
(New_Copy_Tree
(Ref
))));
2545 end Generate_Finalization_Actions
;
2547 --------------------------------
2548 -- Get_Constraint_Association --
2549 --------------------------------
2551 function Get_Constraint_Association
(T
: Entity_Id
) return Node_Id
is
2558 -- If type is private, get constraint from full view. This was
2559 -- previously done in an instance context, but is needed whenever
2560 -- the ancestor part has a discriminant, possibly inherited through
2561 -- multiple derivations.
2563 if Is_Private_Type
(Typ
) and then Present
(Full_View
(Typ
)) then
2564 Typ
:= Full_View
(Typ
);
2567 Indic
:= Subtype_Indication
(Type_Definition
(Parent
(Typ
)));
2569 -- Verify that the subtype indication carries a constraint
2571 if Nkind
(Indic
) = N_Subtype_Indication
2572 and then Present
(Constraint
(Indic
))
2574 return First
(Constraints
(Constraint
(Indic
)));
2578 end Get_Constraint_Association
;
2580 -------------------------------------
2581 -- Get_Explicit_Discriminant_Value --
2582 -------------------------------------
2584 function Get_Explicit_Discriminant_Value
2585 (D
: Entity_Id
) return Node_Id
2592 -- The aggregate has been normalized and all associations have a
2595 Assoc
:= First
(Component_Associations
(N
));
2596 while Present
(Assoc
) loop
2597 Choice
:= First
(Choices
(Assoc
));
2599 if Chars
(Choice
) = Chars
(D
) then
2600 Val
:= Expression
(Assoc
);
2609 end Get_Explicit_Discriminant_Value
;
2611 -------------------------------
2612 -- Init_Hidden_Discriminants --
2613 -------------------------------
2615 procedure Init_Hidden_Discriminants
(Typ
: Entity_Id
; List
: List_Id
) is
2616 function Is_Completely_Hidden_Discriminant
2617 (Discr
: Entity_Id
) return Boolean;
2618 -- Determine whether Discr is a completely hidden discriminant of
2621 ---------------------------------------
2622 -- Is_Completely_Hidden_Discriminant --
2623 ---------------------------------------
2625 function Is_Completely_Hidden_Discriminant
2626 (Discr
: Entity_Id
) return Boolean
2631 -- Use First/Next_Entity as First/Next_Discriminant do not yield
2632 -- completely hidden discriminants.
2634 Item
:= First_Entity
(Typ
);
2635 while Present
(Item
) loop
2636 if Ekind
(Item
) = E_Discriminant
2637 and then Is_Completely_Hidden
(Item
)
2638 and then Chars
(Original_Record_Component
(Item
)) =
2648 end Is_Completely_Hidden_Discriminant
;
2652 Base_Typ
: Entity_Id
;
2654 Discr_Constr
: Elmt_Id
;
2655 Discr_Init
: Node_Id
;
2656 Discr_Val
: Node_Id
;
2657 In_Aggr_Type
: Boolean;
2658 Par_Typ
: Entity_Id
;
2660 -- Start of processing for Init_Hidden_Discriminants
2663 -- The constraints on the hidden discriminants, if present, are kept
2664 -- in the Stored_Constraint list of the type itself, or in that of
2665 -- the base type. If not in the constraints of the aggregate itself,
2666 -- we examine ancestors to find discriminants that are not renamed
2667 -- by other discriminants but constrained explicitly.
2669 In_Aggr_Type
:= True;
2671 Base_Typ
:= Base_Type
(Typ
);
2672 while Is_Derived_Type
(Base_Typ
)
2674 (Present
(Stored_Constraint
(Base_Typ
))
2676 (In_Aggr_Type
and then Present
(Stored_Constraint
(Typ
))))
2678 Par_Typ
:= Etype
(Base_Typ
);
2680 if not Has_Discriminants
(Par_Typ
) then
2684 Discr
:= First_Discriminant
(Par_Typ
);
2686 -- We know that one of the stored-constraint lists is present
2688 if Present
(Stored_Constraint
(Base_Typ
)) then
2689 Discr_Constr
:= First_Elmt
(Stored_Constraint
(Base_Typ
));
2691 -- For private extension, stored constraint may be on full view
2693 elsif Is_Private_Type
(Base_Typ
)
2694 and then Present
(Full_View
(Base_Typ
))
2695 and then Present
(Stored_Constraint
(Full_View
(Base_Typ
)))
2698 First_Elmt
(Stored_Constraint
(Full_View
(Base_Typ
)));
2701 Discr_Constr
:= First_Elmt
(Stored_Constraint
(Typ
));
2704 while Present
(Discr
) and then Present
(Discr_Constr
) loop
2705 Discr_Val
:= Node
(Discr_Constr
);
2707 -- The parent discriminant is renamed in the derived type,
2708 -- nothing to initialize.
2710 -- type Deriv_Typ (Discr : ...)
2711 -- is new Parent_Typ (Discr => Discr);
2713 if Is_Entity_Name
(Discr_Val
)
2714 and then Ekind
(Entity
(Discr_Val
)) = E_Discriminant
2718 -- When the parent discriminant is constrained at the type
2719 -- extension level, it does not appear in the derived type.
2721 -- type Deriv_Typ (Discr : ...)
2722 -- is new Parent_Typ (Discr => Discr,
2723 -- Hidden_Discr => Expression);
2725 elsif Is_Completely_Hidden_Discriminant
(Discr
) then
2728 -- Otherwise initialize the discriminant
2732 Make_OK_Assignment_Statement
(Loc
,
2734 Make_Selected_Component
(Loc
,
2735 Prefix
=> New_Copy_Tree
(Target
),
2736 Selector_Name
=> New_Occurrence_Of
(Discr
, Loc
)),
2737 Expression
=> New_Copy_Tree
(Discr_Val
));
2739 Append_To
(List
, Discr_Init
);
2742 Next_Elmt
(Discr_Constr
);
2743 Next_Discriminant
(Discr
);
2746 In_Aggr_Type
:= False;
2747 Base_Typ
:= Base_Type
(Par_Typ
);
2749 end Init_Hidden_Discriminants
;
2751 --------------------------------
2752 -- Init_Visible_Discriminants --
2753 --------------------------------
2755 procedure Init_Visible_Discriminants
is
2756 Discriminant
: Entity_Id
;
2757 Discriminant_Value
: Node_Id
;
2760 Discriminant
:= First_Discriminant
(Typ
);
2761 while Present
(Discriminant
) loop
2763 Make_Selected_Component
(Loc
,
2764 Prefix
=> New_Copy_Tree
(Target
),
2765 Selector_Name
=> New_Occurrence_Of
(Discriminant
, Loc
));
2767 Discriminant_Value
:=
2768 Get_Discriminant_Value
2769 (Discriminant
, Typ
, Discriminant_Constraint
(N_Typ
));
2772 Make_OK_Assignment_Statement
(Loc
,
2774 Expression
=> New_Copy_Tree
(Discriminant_Value
));
2776 Append_To
(L
, Instr
);
2778 Next_Discriminant
(Discriminant
);
2780 end Init_Visible_Discriminants
;
2782 -------------------------------
2783 -- Init_Stored_Discriminants --
2784 -------------------------------
2786 procedure Init_Stored_Discriminants
is
2787 Discriminant
: Entity_Id
;
2788 Discriminant_Value
: Node_Id
;
2791 Discriminant
:= First_Stored_Discriminant
(Typ
);
2792 while Present
(Discriminant
) loop
2794 Make_Selected_Component
(Loc
,
2795 Prefix
=> New_Copy_Tree
(Target
),
2796 Selector_Name
=> New_Occurrence_Of
(Discriminant
, Loc
));
2798 Discriminant_Value
:=
2799 Get_Discriminant_Value
2800 (Discriminant
, N_Typ
, Discriminant_Constraint
(N_Typ
));
2803 Make_OK_Assignment_Statement
(Loc
,
2805 Expression
=> New_Copy_Tree
(Discriminant_Value
));
2807 Append_To
(L
, Instr
);
2809 Next_Stored_Discriminant
(Discriminant
);
2811 end Init_Stored_Discriminants
;
2813 --------------------------------------
2814 -- Initialize_Ctrl_Record_Component --
2815 --------------------------------------
2817 procedure Initialize_Ctrl_Record_Component
2818 (Rec_Comp
: Node_Id
;
2819 Comp_Typ
: Entity_Id
;
2820 Init_Expr
: Node_Id
;
2824 Hook_Clear
: Node_Id
;
2826 In_Place_Expansion
: Boolean;
2827 -- Flag set when a nonlimited controlled function call requires
2828 -- in-place expansion.
2831 -- Perform a preliminary analysis and resolution to determine what
2832 -- the initialization expression denotes. Unanalyzed function calls
2833 -- may appear as identifiers or indexed components.
2835 if Nkind_In
(Init_Expr
, N_Function_Call
,
2837 N_Indexed_Component
)
2838 and then not Analyzed
(Init_Expr
)
2840 Preanalyze_And_Resolve
(Init_Expr
, Comp_Typ
);
2843 In_Place_Expansion
:=
2844 Nkind
(Init_Expr
) = N_Function_Call
2845 and then not Is_Build_In_Place_Result_Type
(Comp_Typ
);
2847 -- The initialization expression is a controlled function call.
2848 -- Perform in-place removal of side effects to avoid creating a
2851 -- This in-place expansion is not performed for limited transient
2852 -- objects because the initialization is already done in place.
2854 if In_Place_Expansion
then
2856 -- Suppress the removal of side effects by general analysis
2857 -- because this behavior is emulated here. This avoids the
2858 -- generation of a transient scope, which leads to out-of-order
2859 -- adjustment and finalization.
2861 Set_No_Side_Effect_Removal
(Init_Expr
);
2863 -- Install all hook-related declarations and prepare the clean up
2866 Process_Transient_Component
2868 Comp_Typ
=> Comp_Typ
,
2869 Init_Expr
=> Init_Expr
,
2870 Fin_Call
=> Fin_Call
,
2871 Hook_Clear
=> Hook_Clear
,
2875 -- Use the noncontrolled component initialization circuitry to
2876 -- assign the result of the function call to the record component.
2877 -- This also performs tag adjustment and [deep] adjustment of the
2878 -- record component.
2880 Initialize_Record_Component
2881 (Rec_Comp
=> Rec_Comp
,
2882 Comp_Typ
=> Comp_Typ
,
2883 Init_Expr
=> Init_Expr
,
2886 -- At this point the record component is fully initialized. Complete
2887 -- the processing of the controlled record component by finalizing
2888 -- the transient function result.
2890 if In_Place_Expansion
then
2891 Process_Transient_Component_Completion
2894 Fin_Call
=> Fin_Call
,
2895 Hook_Clear
=> Hook_Clear
,
2898 end Initialize_Ctrl_Record_Component
;
2900 ---------------------------------
2901 -- Initialize_Record_Component --
2902 ---------------------------------
2904 procedure Initialize_Record_Component
2905 (Rec_Comp
: Node_Id
;
2906 Comp_Typ
: Entity_Id
;
2907 Init_Expr
: Node_Id
;
2910 Exceptions_OK
: constant Boolean :=
2911 not Restriction_Active
(No_Exception_Propagation
);
2913 Finalization_OK
: constant Boolean := Needs_Finalization
(Comp_Typ
);
2915 Full_Typ
: constant Entity_Id
:= Underlying_Type
(Comp_Typ
);
2917 Blk_Stmts
: List_Id
;
2918 Init_Stmt
: Node_Id
;
2921 -- Protect the initialization statements from aborts. Generate:
2925 if Finalization_OK
and Abort_Allowed
then
2926 if Exceptions_OK
then
2927 Blk_Stmts
:= New_List
;
2932 Append_To
(Blk_Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
2934 -- Otherwise aborts are not allowed. All generated code is added
2935 -- directly to the input list.
2941 -- Initialize the record component. Generate:
2943 -- Rec_Comp := Init_Expr;
2945 -- Note that the initialization expression is NOT replicated because
2946 -- only a single component may be initialized by it.
2949 Make_OK_Assignment_Statement
(Loc
,
2950 Name
=> New_Copy_Tree
(Rec_Comp
),
2951 Expression
=> Init_Expr
);
2952 Set_No_Ctrl_Actions
(Init_Stmt
);
2954 Append_To
(Blk_Stmts
, Init_Stmt
);
2956 -- Adjust the tag due to a possible view conversion. Generate:
2958 -- Rec_Comp._tag := Full_TypeP;
2960 if Tagged_Type_Expansion
and then Is_Tagged_Type
(Comp_Typ
) then
2961 Append_To
(Blk_Stmts
,
2962 Make_OK_Assignment_Statement
(Loc
,
2964 Make_Selected_Component
(Loc
,
2965 Prefix
=> New_Copy_Tree
(Rec_Comp
),
2968 (First_Tag_Component
(Full_Typ
), Loc
)),
2971 Unchecked_Convert_To
(RTE
(RE_Tag
),
2973 (Node
(First_Elmt
(Access_Disp_Table
(Full_Typ
))),
2977 -- Adjust the component. Generate:
2979 -- [Deep_]Adjust (Rec_Comp);
2982 and then not Is_Limited_Type
(Comp_Typ
)
2983 and then not Is_Build_In_Place_Function_Call
(Init_Expr
)
2987 (Obj_Ref
=> New_Copy_Tree
(Rec_Comp
),
2990 -- Guard against a missing [Deep_]Adjust when the component type
2991 -- was not properly frozen.
2993 if Present
(Adj_Call
) then
2994 Append_To
(Blk_Stmts
, Adj_Call
);
2998 -- Complete the protection of the initialization statements
3000 if Finalization_OK
and Abort_Allowed
then
3002 -- Wrap the initialization statements in a block to catch a
3003 -- potential exception. Generate:
3007 -- Rec_Comp := Init_Expr;
3008 -- Rec_Comp._tag := Full_TypP;
3009 -- [Deep_]Adjust (Rec_Comp);
3011 -- Abort_Undefer_Direct;
3014 if Exceptions_OK
then
3016 Build_Abort_Undefer_Block
(Loc
,
3020 -- Otherwise exceptions are not propagated. Generate:
3023 -- Rec_Comp := Init_Expr;
3024 -- Rec_Comp._tag := Full_TypP;
3025 -- [Deep_]Adjust (Rec_Comp);
3029 Append_To
(Blk_Stmts
,
3030 Build_Runtime_Call
(Loc
, RE_Abort_Undefer
));
3033 end Initialize_Record_Component
;
3035 -------------------------
3036 -- Is_Int_Range_Bounds --
3037 -------------------------
3039 function Is_Int_Range_Bounds
(Bounds
: Node_Id
) return Boolean is
3041 return Nkind
(Bounds
) = N_Range
3042 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
3043 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
;
3044 end Is_Int_Range_Bounds
;
3050 function Replace_Type
(Expr
: Node_Id
) return Traverse_Result
is
3052 -- Note regarding the Root_Type test below: Aggregate components for
3053 -- self-referential types include attribute references to the current
3054 -- instance, of the form: Typ'access, etc.. These references are
3055 -- rewritten as references to the target of the aggregate: the
3056 -- left-hand side of an assignment, the entity in a declaration,
3057 -- or a temporary. Without this test, we would improperly extended
3058 -- this rewriting to attribute references whose prefix was not the
3059 -- type of the aggregate.
3061 if Nkind
(Expr
) = N_Attribute_Reference
3062 and then Is_Entity_Name
(Prefix
(Expr
))
3063 and then Is_Type
(Entity
(Prefix
(Expr
)))
3064 and then Root_Type
(Etype
(N
)) = Root_Type
(Entity
(Prefix
(Expr
)))
3066 if Is_Entity_Name
(Lhs
) then
3067 Rewrite
(Prefix
(Expr
), New_Occurrence_Of
(Entity
(Lhs
), Loc
));
3071 Make_Attribute_Reference
(Loc
,
3072 Attribute_Name
=> Name_Unrestricted_Access
,
3073 Prefix
=> New_Copy_Tree
(Lhs
)));
3074 Set_Analyzed
(Parent
(Expr
), False);
3081 --------------------------
3082 -- Rewrite_Discriminant --
3083 --------------------------
3085 function Rewrite_Discriminant
(Expr
: Node_Id
) return Traverse_Result
is
3087 if Is_Entity_Name
(Expr
)
3088 and then Present
(Entity
(Expr
))
3089 and then Ekind
(Entity
(Expr
)) = E_In_Parameter
3090 and then Present
(Discriminal_Link
(Entity
(Expr
)))
3091 and then Scope
(Discriminal_Link
(Entity
(Expr
))) =
3092 Base_Type
(Etype
(N
))
3095 Make_Selected_Component
(Loc
,
3096 Prefix
=> New_Copy_Tree
(Lhs
),
3097 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Expr
))));
3101 end Rewrite_Discriminant
;
3103 procedure Replace_Discriminants
is
3104 new Traverse_Proc
(Rewrite_Discriminant
);
3106 procedure Replace_Self_Reference
is
3107 new Traverse_Proc
(Replace_Type
);
3109 -- Start of processing for Build_Record_Aggr_Code
3112 if Has_Self_Reference
(N
) then
3113 Replace_Self_Reference
(N
);
3116 -- If the target of the aggregate is class-wide, we must convert it
3117 -- to the actual type of the aggregate, so that the proper components
3118 -- are visible. We know already that the types are compatible.
3120 if Present
(Etype
(Lhs
))
3121 and then Is_Class_Wide_Type
(Etype
(Lhs
))
3123 Target
:= Unchecked_Convert_To
(Typ
, Lhs
);
3128 -- Deal with the ancestor part of extension aggregates or with the
3129 -- discriminants of the root type.
3131 if Nkind
(N
) = N_Extension_Aggregate
then
3133 Ancestor
: constant Node_Id
:= Ancestor_Part
(N
);
3138 -- If the ancestor part is a subtype mark "T", we generate
3140 -- init-proc (T (tmp)); if T is constrained and
3141 -- init-proc (S (tmp)); where S applies an appropriate
3142 -- constraint if T is unconstrained
3144 if Is_Entity_Name
(Ancestor
)
3145 and then Is_Type
(Entity
(Ancestor
))
3147 Ancestor_Is_Subtype_Mark
:= True;
3149 if Is_Constrained
(Entity
(Ancestor
)) then
3150 Init_Typ
:= Entity
(Ancestor
);
3152 -- For an ancestor part given by an unconstrained type mark,
3153 -- create a subtype constrained by appropriate corresponding
3154 -- discriminant values coming from either associations of the
3155 -- aggregate or a constraint on a parent type. The subtype will
3156 -- be used to generate the correct default value for the
3159 elsif Has_Discriminants
(Entity
(Ancestor
)) then
3161 Anc_Typ
: constant Entity_Id
:= Entity
(Ancestor
);
3162 Anc_Constr
: constant List_Id
:= New_List
;
3163 Discrim
: Entity_Id
;
3164 Disc_Value
: Node_Id
;
3165 New_Indic
: Node_Id
;
3166 Subt_Decl
: Node_Id
;
3169 Discrim
:= First_Discriminant
(Anc_Typ
);
3170 while Present
(Discrim
) loop
3171 Disc_Value
:= Ancestor_Discriminant_Value
(Discrim
);
3173 -- If no usable discriminant in ancestors, check
3174 -- whether aggregate has an explicit value for it.
3176 if No
(Disc_Value
) then
3178 Get_Explicit_Discriminant_Value
(Discrim
);
3181 Append_To
(Anc_Constr
, Disc_Value
);
3182 Next_Discriminant
(Discrim
);
3186 Make_Subtype_Indication
(Loc
,
3187 Subtype_Mark
=> New_Occurrence_Of
(Anc_Typ
, Loc
),
3189 Make_Index_Or_Discriminant_Constraint
(Loc
,
3190 Constraints
=> Anc_Constr
));
3192 Init_Typ
:= Create_Itype
(Ekind
(Anc_Typ
), N
);
3195 Make_Subtype_Declaration
(Loc
,
3196 Defining_Identifier
=> Init_Typ
,
3197 Subtype_Indication
=> New_Indic
);
3199 -- Itypes must be analyzed with checks off Declaration
3200 -- must have a parent for proper handling of subsidiary
3203 Set_Parent
(Subt_Decl
, N
);
3204 Analyze
(Subt_Decl
, Suppress
=> All_Checks
);
3208 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
3209 Set_Assignment_OK
(Ref
);
3211 if not Is_Interface
(Init_Typ
) then
3213 Build_Initialization_Call
(Loc
,
3216 In_Init_Proc
=> Within_Init_Proc
,
3217 With_Default_Init
=> Has_Default_Init_Comps
(N
)
3219 Has_Task
(Base_Type
(Init_Typ
))));
3221 if Is_Constrained
(Entity
(Ancestor
))
3222 and then Has_Discriminants
(Entity
(Ancestor
))
3224 Check_Ancestor_Discriminants
(Entity
(Ancestor
));
3228 -- Handle calls to C++ constructors
3230 elsif Is_CPP_Constructor_Call
(Ancestor
) then
3231 Init_Typ
:= Etype
(Ancestor
);
3232 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
3233 Set_Assignment_OK
(Ref
);
3236 Build_Initialization_Call
(Loc
,
3239 In_Init_Proc
=> Within_Init_Proc
,
3240 With_Default_Init
=> Has_Default_Init_Comps
(N
),
3241 Constructor_Ref
=> Ancestor
));
3243 -- Ada 2005 (AI-287): If the ancestor part is an aggregate of
3244 -- limited type, a recursive call expands the ancestor. Note that
3245 -- in the limited case, the ancestor part must be either a
3246 -- function call (possibly qualified) or aggregate (definitely
3249 elsif Is_Limited_Type
(Etype
(Ancestor
))
3250 and then Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
3251 N_Extension_Aggregate
)
3253 Ancestor_Is_Expression
:= True;
3255 -- Set up finalization data for enclosing record, because
3256 -- controlled subcomponents of the ancestor part will be
3259 Generate_Finalization_Actions
;
3262 Build_Record_Aggr_Code
3263 (N
=> Unqualify
(Ancestor
),
3264 Typ
=> Etype
(Unqualify
(Ancestor
)),
3267 -- If the ancestor part is an expression "E", we generate
3271 -- In Ada 2005, this includes the case of a (possibly qualified)
3272 -- limited function call. The assignment will turn into a
3273 -- build-in-place function call (for further details, see
3274 -- Make_Build_In_Place_Call_In_Assignment).
3277 Ancestor_Is_Expression
:= True;
3278 Init_Typ
:= Etype
(Ancestor
);
3280 -- If the ancestor part is an aggregate, force its full
3281 -- expansion, which was delayed.
3283 if Nkind_In
(Unqualify
(Ancestor
), N_Aggregate
,
3284 N_Extension_Aggregate
)
3286 Set_Analyzed
(Ancestor
, False);
3287 Set_Analyzed
(Expression
(Ancestor
), False);
3290 Ref
:= Convert_To
(Init_Typ
, New_Copy_Tree
(Target
));
3291 Set_Assignment_OK
(Ref
);
3293 -- Make the assignment without usual controlled actions, since
3294 -- we only want to Adjust afterwards, but not to Finalize
3295 -- beforehand. Add manual Adjust when necessary.
3297 Assign
:= New_List
(
3298 Make_OK_Assignment_Statement
(Loc
,
3300 Expression
=> Ancestor
));
3301 Set_No_Ctrl_Actions
(First
(Assign
));
3303 -- Assign the tag now to make sure that the dispatching call in
3304 -- the subsequent deep_adjust works properly (unless
3305 -- Tagged_Type_Expansion where tags are implicit).
3307 if Tagged_Type_Expansion
then
3309 Make_OK_Assignment_Statement
(Loc
,
3311 Make_Selected_Component
(Loc
,
3312 Prefix
=> New_Copy_Tree
(Target
),
3315 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
3318 Unchecked_Convert_To
(RTE
(RE_Tag
),
3321 (Access_Disp_Table
(Base_Type
(Typ
)))),
3324 Set_Assignment_OK
(Name
(Instr
));
3325 Append_To
(Assign
, Instr
);
3327 -- Ada 2005 (AI-251): If tagged type has progenitors we must
3328 -- also initialize tags of the secondary dispatch tables.
3330 if Has_Interfaces
(Base_Type
(Typ
)) then
3332 (Typ
=> Base_Type
(Typ
),
3334 Stmts_List
=> Assign
,
3335 Init_Tags_List
=> Assign
);
3339 -- Call Adjust manually
3341 if Needs_Finalization
(Etype
(Ancestor
))
3342 and then not Is_Limited_Type
(Etype
(Ancestor
))
3343 and then not Is_Build_In_Place_Function_Call
(Ancestor
)
3347 (Obj_Ref
=> New_Copy_Tree
(Ref
),
3348 Typ
=> Etype
(Ancestor
));
3350 -- Guard against a missing [Deep_]Adjust when the ancestor
3351 -- type was not properly frozen.
3353 if Present
(Adj_Call
) then
3354 Append_To
(Assign
, Adj_Call
);
3359 Make_Unsuppress_Block
(Loc
, Name_Discriminant_Check
, Assign
));
3361 if Has_Discriminants
(Init_Typ
) then
3362 Check_Ancestor_Discriminants
(Init_Typ
);
3366 pragma Assert
(Nkind
(N
) = N_Extension_Aggregate
);
3368 (not (Ancestor_Is_Expression
and Ancestor_Is_Subtype_Mark
));
3371 -- Generate assignments of hidden discriminants. If the base type is
3372 -- an unchecked union, the discriminants are unknown to the back-end
3373 -- and absent from a value of the type, so assignments for them are
3376 if Has_Discriminants
(Typ
)
3377 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
3379 Init_Hidden_Discriminants
(Typ
, L
);
3382 -- Normal case (not an extension aggregate)
3385 -- Generate the discriminant expressions, component by component.
3386 -- If the base type is an unchecked union, the discriminants are
3387 -- unknown to the back-end and absent from a value of the type, so
3388 -- assignments for them are not emitted.
3390 if Has_Discriminants
(Typ
)
3391 and then not Is_Unchecked_Union
(Base_Type
(Typ
))
3393 Init_Hidden_Discriminants
(Typ
, L
);
3395 -- Generate discriminant init values for the visible discriminants
3397 Init_Visible_Discriminants
;
3399 if Is_Derived_Type
(N_Typ
) then
3400 Init_Stored_Discriminants
;
3405 -- For CPP types we generate an implicit call to the C++ default
3406 -- constructor to ensure the proper initialization of the _Tag
3409 if Is_CPP_Class
(Root_Type
(Typ
)) and then CPP_Num_Prims
(Typ
) > 0 then
3410 Invoke_Constructor
: declare
3411 CPP_Parent
: constant Entity_Id
:= Enclosing_CPP_Parent
(Typ
);
3413 procedure Invoke_IC_Proc
(T
: Entity_Id
);
3414 -- Recursive routine used to climb to parents. Required because
3415 -- parents must be initialized before descendants to ensure
3416 -- propagation of inherited C++ slots.
3418 --------------------
3419 -- Invoke_IC_Proc --
3420 --------------------
3422 procedure Invoke_IC_Proc
(T
: Entity_Id
) is
3424 -- Avoid generating extra calls. Initialization required
3425 -- only for types defined from the level of derivation of
3426 -- type of the constructor and the type of the aggregate.
3428 if T
= CPP_Parent
then
3432 Invoke_IC_Proc
(Etype
(T
));
3434 -- Generate call to the IC routine
3436 if Present
(CPP_Init_Proc
(T
)) then
3438 Make_Procedure_Call_Statement
(Loc
,
3439 Name
=> New_Occurrence_Of
(CPP_Init_Proc
(T
), Loc
)));
3443 -- Start of processing for Invoke_Constructor
3446 -- Implicit invocation of the C++ constructor
3448 if Nkind
(N
) = N_Aggregate
then
3450 Make_Procedure_Call_Statement
(Loc
,
3452 New_Occurrence_Of
(Base_Init_Proc
(CPP_Parent
), Loc
),
3453 Parameter_Associations
=> New_List
(
3454 Unchecked_Convert_To
(CPP_Parent
,
3455 New_Copy_Tree
(Lhs
)))));
3458 Invoke_IC_Proc
(Typ
);
3459 end Invoke_Constructor
;
3462 -- Generate the assignments, component by component
3464 -- tmp.comp1 := Expr1_From_Aggr;
3465 -- tmp.comp2 := Expr2_From_Aggr;
3468 Comp
:= First
(Component_Associations
(N
));
3469 while Present
(Comp
) loop
3470 Selector
:= Entity
(First
(Choices
(Comp
)));
3474 if Is_CPP_Constructor_Call
(Expression
(Comp
)) then
3476 Build_Initialization_Call
(Loc
,
3478 Make_Selected_Component
(Loc
,
3479 Prefix
=> New_Copy_Tree
(Target
),
3480 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
)),
3481 Typ
=> Etype
(Selector
),
3483 With_Default_Init
=> True,
3484 Constructor_Ref
=> Expression
(Comp
)));
3486 -- Ada 2005 (AI-287): For each default-initialized component generate
3487 -- a call to the corresponding IP subprogram if available.
3489 elsif Box_Present
(Comp
)
3490 and then Has_Non_Null_Base_Init_Proc
(Etype
(Selector
))
3492 if Ekind
(Selector
) /= E_Discriminant
then
3493 Generate_Finalization_Actions
;
3496 -- Ada 2005 (AI-287): If the component type has tasks then
3497 -- generate the activation chain and master entities (except
3498 -- in case of an allocator because in that case these entities
3499 -- are generated by Build_Task_Allocate_Block_With_Init_Stmts).
3502 Ctype
: constant Entity_Id
:= Etype
(Selector
);
3503 Inside_Allocator
: Boolean := False;
3504 P
: Node_Id
:= Parent
(N
);
3507 if Is_Task_Type
(Ctype
) or else Has_Task
(Ctype
) then
3508 while Present
(P
) loop
3509 if Nkind
(P
) = N_Allocator
then
3510 Inside_Allocator
:= True;
3517 if not Inside_Init_Proc
and not Inside_Allocator
then
3518 Build_Activation_Chain_Entity
(N
);
3524 Build_Initialization_Call
(Loc
,
3525 Id_Ref
=> Make_Selected_Component
(Loc
,
3526 Prefix
=> New_Copy_Tree
(Target
),
3528 New_Occurrence_Of
(Selector
, Loc
)),
3529 Typ
=> Etype
(Selector
),
3531 With_Default_Init
=> True));
3533 -- Prepare for component assignment
3535 elsif Ekind
(Selector
) /= E_Discriminant
3536 or else Nkind
(N
) = N_Extension_Aggregate
3538 -- All the discriminants have now been assigned
3540 -- This is now a good moment to initialize and attach all the
3541 -- controllers. Their position may depend on the discriminants.
3543 if Ekind
(Selector
) /= E_Discriminant
then
3544 Generate_Finalization_Actions
;
3547 Comp_Type
:= Underlying_Type
(Etype
(Selector
));
3549 Make_Selected_Component
(Loc
,
3550 Prefix
=> New_Copy_Tree
(Target
),
3551 Selector_Name
=> New_Occurrence_Of
(Selector
, Loc
));
3553 if Nkind
(Expression
(Comp
)) = N_Qualified_Expression
then
3554 Expr_Q
:= Expression
(Expression
(Comp
));
3556 Expr_Q
:= Expression
(Comp
);
3559 -- Now either create the assignment or generate the code for the
3560 -- inner aggregate top-down.
3562 if Is_Delayed_Aggregate
(Expr_Q
) then
3564 -- We have the following case of aggregate nesting inside
3565 -- an object declaration:
3567 -- type Arr_Typ is array (Integer range <>) of ...;
3569 -- type Rec_Typ (...) is record
3570 -- Obj_Arr_Typ : Arr_Typ (A .. B);
3573 -- Obj_Rec_Typ : Rec_Typ := (...,
3574 -- Obj_Arr_Typ => (X => (...), Y => (...)));
3576 -- The length of the ranges of the aggregate and Obj_Add_Typ
3577 -- are equal (B - A = Y - X), but they do not coincide (X /=
3578 -- A and B /= Y). This case requires array sliding which is
3579 -- performed in the following manner:
3581 -- subtype Arr_Sub is Arr_Typ (X .. Y);
3583 -- Temp (X) := (...);
3585 -- Temp (Y) := (...);
3586 -- Obj_Rec_Typ.Obj_Arr_Typ := Temp;
3588 if Ekind
(Comp_Type
) = E_Array_Subtype
3589 and then Is_Int_Range_Bounds
(Aggregate_Bounds
(Expr_Q
))
3590 and then Is_Int_Range_Bounds
(First_Index
(Comp_Type
))
3592 Compatible_Int_Bounds
3593 (Agg_Bounds
=> Aggregate_Bounds
(Expr_Q
),
3594 Typ_Bounds
=> First_Index
(Comp_Type
))
3596 -- Create the array subtype with bounds equal to those of
3597 -- the corresponding aggregate.
3600 SubE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
3602 SubD
: constant Node_Id
:=
3603 Make_Subtype_Declaration
(Loc
,
3604 Defining_Identifier
=> SubE
,
3605 Subtype_Indication
=>
3606 Make_Subtype_Indication
(Loc
,
3608 New_Occurrence_Of
(Etype
(Comp_Type
), Loc
),
3610 Make_Index_Or_Discriminant_Constraint
3612 Constraints
=> New_List
(
3614 (Aggregate_Bounds
(Expr_Q
))))));
3616 -- Create a temporary array of the above subtype which
3617 -- will be used to capture the aggregate assignments.
3619 TmpE
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A', N
);
3621 TmpD
: constant Node_Id
:=
3622 Make_Object_Declaration
(Loc
,
3623 Defining_Identifier
=> TmpE
,
3624 Object_Definition
=> New_Occurrence_Of
(SubE
, Loc
));
3627 Set_No_Initialization
(TmpD
);
3628 Append_To
(L
, SubD
);
3629 Append_To
(L
, TmpD
);
3631 -- Expand aggregate into assignments to the temp array
3634 Late_Expansion
(Expr_Q
, Comp_Type
,
3635 New_Occurrence_Of
(TmpE
, Loc
)));
3640 Make_Assignment_Statement
(Loc
,
3641 Name
=> New_Copy_Tree
(Comp_Expr
),
3642 Expression
=> New_Occurrence_Of
(TmpE
, Loc
)));
3645 -- Normal case (sliding not required)
3649 Late_Expansion
(Expr_Q
, Comp_Type
, Comp_Expr
));
3652 -- Expr_Q is not delayed aggregate
3655 if Has_Discriminants
(Typ
) then
3656 Replace_Discriminants
(Expr_Q
);
3658 -- If the component is an array type that depends on
3659 -- discriminants, and the expression is a single Others
3660 -- clause, create an explicit subtype for it because the
3661 -- backend has troubles recovering the actual bounds.
3663 if Nkind
(Expr_Q
) = N_Aggregate
3664 and then Is_Array_Type
(Comp_Type
)
3665 and then Present
(Component_Associations
(Expr_Q
))
3668 Assoc
: constant Node_Id
:=
3669 First
(Component_Associations
(Expr_Q
));
3673 if Nkind
(First
(Choices
(Assoc
))) = N_Others_Choice
3676 Build_Actual_Subtype_Of_Component
3677 (Comp_Type
, Comp_Expr
);
3679 -- If the component type does not in fact depend on
3680 -- discriminants, the subtype declaration is empty.
3682 if Present
(Decl
) then
3683 Append_To
(L
, Decl
);
3684 Set_Etype
(Comp_Expr
, Defining_Entity
(Decl
));
3691 if Modify_Tree_For_C
3692 and then Nkind
(Expr_Q
) = N_Aggregate
3693 and then Is_Array_Type
(Etype
(Expr_Q
))
3694 and then Present
(First_Index
(Etype
(Expr_Q
)))
3697 Expr_Q_Type
: constant Node_Id
:= Etype
(Expr_Q
);
3700 Build_Array_Aggr_Code
3702 Ctype
=> Component_Type
(Expr_Q_Type
),
3703 Index
=> First_Index
(Expr_Q_Type
),
3706 Is_Scalar_Type
(Component_Type
(Expr_Q_Type
))));
3710 -- Handle an initialization expression of a controlled type
3711 -- in case it denotes a function call. In general such a
3712 -- scenario will produce a transient scope, but this will
3713 -- lead to wrong order of initialization, adjustment, and
3714 -- finalization in the context of aggregates.
3716 -- Target.Comp := Ctrl_Func_Call;
3719 -- Trans_Obj : ... := Ctrl_Func_Call; -- object
3720 -- Target.Comp := Trans_Obj;
3721 -- Finalize (Trans_Obj);
3723 -- Target.Comp._tag := ...;
3724 -- Adjust (Target.Comp);
3726 -- In the example above, the call to Finalize occurs too
3727 -- early and as a result it may leave the record component
3728 -- in a bad state. Finalization of the transient object
3729 -- should really happen after adjustment.
3731 -- To avoid this scenario, perform in-place side-effect
3732 -- removal of the function call. This eliminates the
3733 -- transient property of the function result and ensures
3734 -- correct order of actions.
3736 -- Res : ... := Ctrl_Func_Call;
3737 -- Target.Comp := Res;
3738 -- Target.Comp._tag := ...;
3739 -- Adjust (Target.Comp);
3742 if Needs_Finalization
(Comp_Type
)
3743 and then Nkind
(Expr_Q
) /= N_Aggregate
3745 Initialize_Ctrl_Record_Component
3746 (Rec_Comp
=> Comp_Expr
,
3747 Comp_Typ
=> Etype
(Selector
),
3748 Init_Expr
=> Expr_Q
,
3751 -- Otherwise perform single component initialization
3754 Initialize_Record_Component
3755 (Rec_Comp
=> Comp_Expr
,
3756 Comp_Typ
=> Etype
(Selector
),
3757 Init_Expr
=> Expr_Q
,
3763 -- comment would be good here ???
3765 elsif Ekind
(Selector
) = E_Discriminant
3766 and then Nkind
(N
) /= N_Extension_Aggregate
3767 and then Nkind
(Parent
(N
)) = N_Component_Association
3768 and then Is_Constrained
(Typ
)
3770 -- We must check that the discriminant value imposed by the
3771 -- context is the same as the value given in the subaggregate,
3772 -- because after the expansion into assignments there is no
3773 -- record on which to perform a regular discriminant check.
3780 D_Val
:= First_Elmt
(Discriminant_Constraint
(Typ
));
3781 Disc
:= First_Discriminant
(Typ
);
3782 while Chars
(Disc
) /= Chars
(Selector
) loop
3783 Next_Discriminant
(Disc
);
3787 pragma Assert
(Present
(D_Val
));
3789 -- This check cannot performed for components that are
3790 -- constrained by a current instance, because this is not a
3791 -- value that can be compared with the actual constraint.
3793 if Nkind
(Node
(D_Val
)) /= N_Attribute_Reference
3794 or else not Is_Entity_Name
(Prefix
(Node
(D_Val
)))
3795 or else not Is_Type
(Entity
(Prefix
(Node
(D_Val
))))
3798 Make_Raise_Constraint_Error
(Loc
,
3801 Left_Opnd
=> New_Copy_Tree
(Node
(D_Val
)),
3802 Right_Opnd
=> Expression
(Comp
)),
3803 Reason
=> CE_Discriminant_Check_Failed
));
3806 -- Find self-reference in previous discriminant assignment,
3807 -- and replace with proper expression.
3814 while Present
(Ass
) loop
3815 if Nkind
(Ass
) = N_Assignment_Statement
3816 and then Nkind
(Name
(Ass
)) = N_Selected_Component
3817 and then Chars
(Selector_Name
(Name
(Ass
))) =
3821 (Ass
, New_Copy_Tree
(Expression
(Comp
)));
3834 -- If the type is tagged, the tag needs to be initialized (unless we
3835 -- are in VM-mode where tags are implicit). It is done late in the
3836 -- initialization process because in some cases, we call the init
3837 -- proc of an ancestor which will not leave out the right tag.
3839 if Ancestor_Is_Expression
then
3842 -- For CPP types we generated a call to the C++ default constructor
3843 -- before the components have been initialized to ensure the proper
3844 -- initialization of the _Tag component (see above).
3846 elsif Is_CPP_Class
(Typ
) then
3849 elsif Is_Tagged_Type
(Typ
) and then Tagged_Type_Expansion
then
3851 Make_OK_Assignment_Statement
(Loc
,
3853 Make_Selected_Component
(Loc
,
3854 Prefix
=> New_Copy_Tree
(Target
),
3857 (First_Tag_Component
(Base_Type
(Typ
)), Loc
)),
3860 Unchecked_Convert_To
(RTE
(RE_Tag
),
3862 (Node
(First_Elmt
(Access_Disp_Table
(Base_Type
(Typ
)))),
3865 Append_To
(L
, Instr
);
3867 -- Ada 2005 (AI-251): If the tagged type has been derived from an
3868 -- abstract interfaces we must also initialize the tags of the
3869 -- secondary dispatch tables.
3871 if Has_Interfaces
(Base_Type
(Typ
)) then
3873 (Typ
=> Base_Type
(Typ
),
3876 Init_Tags_List
=> L
);
3880 -- If the controllers have not been initialized yet (by lack of non-
3881 -- discriminant components), let's do it now.
3883 Generate_Finalization_Actions
;
3886 end Build_Record_Aggr_Code
;
3888 ---------------------------------------
3889 -- Collect_Initialization_Statements --
3890 ---------------------------------------
3892 procedure Collect_Initialization_Statements
3895 Node_After
: Node_Id
)
3897 Loc
: constant Source_Ptr
:= Sloc
(N
);
3898 Init_Actions
: constant List_Id
:= New_List
;
3899 Init_Node
: Node_Id
;
3900 Comp_Stmt
: Node_Id
;
3903 -- Nothing to do if Obj is already frozen, as in this case we known we
3904 -- won't need to move the initialization statements about later on.
3906 if Is_Frozen
(Obj
) then
3911 while Next
(Init_Node
) /= Node_After
loop
3912 Append_To
(Init_Actions
, Remove_Next
(Init_Node
));
3915 if not Is_Empty_List
(Init_Actions
) then
3916 Comp_Stmt
:= Make_Compound_Statement
(Loc
, Actions
=> Init_Actions
);
3917 Insert_Action_After
(Init_Node
, Comp_Stmt
);
3918 Set_Initialization_Statements
(Obj
, Comp_Stmt
);
3920 end Collect_Initialization_Statements
;
3922 -------------------------------
3923 -- Convert_Aggr_In_Allocator --
3924 -------------------------------
3926 procedure Convert_Aggr_In_Allocator
3931 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3932 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3933 Temp
: constant Entity_Id
:= Defining_Identifier
(Decl
);
3935 Occ
: constant Node_Id
:=
3936 Unchecked_Convert_To
(Typ
,
3937 Make_Explicit_Dereference
(Loc
, New_Occurrence_Of
(Temp
, Loc
)));
3940 if Is_Array_Type
(Typ
) then
3941 Convert_Array_Aggr_In_Allocator
(Decl
, Aggr
, Occ
);
3943 elsif Has_Default_Init_Comps
(Aggr
) then
3945 L
: constant List_Id
:= New_List
;
3946 Init_Stmts
: List_Id
;
3949 Init_Stmts
:= Late_Expansion
(Aggr
, Typ
, Occ
);
3951 if Has_Task
(Typ
) then
3952 Build_Task_Allocate_Block_With_Init_Stmts
(L
, Aggr
, Init_Stmts
);
3953 Insert_Actions
(Alloc
, L
);
3955 Insert_Actions
(Alloc
, Init_Stmts
);
3960 Insert_Actions
(Alloc
, Late_Expansion
(Aggr
, Typ
, Occ
));
3962 end Convert_Aggr_In_Allocator
;
3964 --------------------------------
3965 -- Convert_Aggr_In_Assignment --
3966 --------------------------------
3968 procedure Convert_Aggr_In_Assignment
(N
: Node_Id
) is
3969 Aggr
: Node_Id
:= Expression
(N
);
3970 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3971 Occ
: constant Node_Id
:= New_Copy_Tree
(Name
(N
));
3974 if Nkind
(Aggr
) = N_Qualified_Expression
then
3975 Aggr
:= Expression
(Aggr
);
3978 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
3979 end Convert_Aggr_In_Assignment
;
3981 ---------------------------------
3982 -- Convert_Aggr_In_Object_Decl --
3983 ---------------------------------
3985 procedure Convert_Aggr_In_Object_Decl
(N
: Node_Id
) is
3986 Obj
: constant Entity_Id
:= Defining_Identifier
(N
);
3987 Aggr
: Node_Id
:= Expression
(N
);
3988 Loc
: constant Source_Ptr
:= Sloc
(Aggr
);
3989 Typ
: constant Entity_Id
:= Etype
(Aggr
);
3990 Occ
: constant Node_Id
:= New_Occurrence_Of
(Obj
, Loc
);
3992 function Discriminants_Ok
return Boolean;
3993 -- If the object type is constrained, the discriminants in the
3994 -- aggregate must be checked against the discriminants of the subtype.
3995 -- This cannot be done using Apply_Discriminant_Checks because after
3996 -- expansion there is no aggregate left to check.
3998 ----------------------
3999 -- Discriminants_Ok --
4000 ----------------------
4002 function Discriminants_Ok
return Boolean is
4003 Cond
: Node_Id
:= Empty
;
4012 D
:= First_Discriminant
(Typ
);
4013 Disc1
:= First_Elmt
(Discriminant_Constraint
(Typ
));
4014 Disc2
:= First_Elmt
(Discriminant_Constraint
(Etype
(Obj
)));
4015 while Present
(Disc1
) and then Present
(Disc2
) loop
4016 Val1
:= Node
(Disc1
);
4017 Val2
:= Node
(Disc2
);
4019 if not Is_OK_Static_Expression
(Val1
)
4020 or else not Is_OK_Static_Expression
(Val2
)
4022 Check
:= Make_Op_Ne
(Loc
,
4023 Left_Opnd
=> Duplicate_Subexpr
(Val1
),
4024 Right_Opnd
=> Duplicate_Subexpr
(Val2
));
4030 Cond
:= Make_Or_Else
(Loc
,
4032 Right_Opnd
=> Check
);
4035 elsif Expr_Value
(Val1
) /= Expr_Value
(Val2
) then
4036 Apply_Compile_Time_Constraint_Error
(Aggr
,
4037 Msg
=> "incorrect value for discriminant&??",
4038 Reason
=> CE_Discriminant_Check_Failed
,
4043 Next_Discriminant
(D
);
4048 -- If any discriminant constraint is non-static, emit a check
4050 if Present
(Cond
) then
4052 Make_Raise_Constraint_Error
(Loc
,
4054 Reason
=> CE_Discriminant_Check_Failed
));
4058 end Discriminants_Ok
;
4060 -- Start of processing for Convert_Aggr_In_Object_Decl
4063 Set_Assignment_OK
(Occ
);
4065 if Nkind
(Aggr
) = N_Qualified_Expression
then
4066 Aggr
:= Expression
(Aggr
);
4069 if Has_Discriminants
(Typ
)
4070 and then Typ
/= Etype
(Obj
)
4071 and then Is_Constrained
(Etype
(Obj
))
4072 and then not Discriminants_Ok
4077 -- If the context is an extended return statement, it has its own
4078 -- finalization machinery (i.e. works like a transient scope) and
4079 -- we do not want to create an additional one, because objects on
4080 -- the finalization list of the return must be moved to the caller's
4081 -- finalization list to complete the return.
4083 -- However, if the aggregate is limited, it is built in place, and the
4084 -- controlled components are not assigned to intermediate temporaries
4085 -- so there is no need for a transient scope in this case either.
4087 if Requires_Transient_Scope
(Typ
)
4088 and then Ekind
(Current_Scope
) /= E_Return_Statement
4089 and then not Is_Limited_Type
(Typ
)
4091 Establish_Transient_Scope
(Aggr
, Sec_Stack
=> False);
4095 Node_After
: constant Node_Id
:= Next
(N
);
4097 Insert_Actions_After
(N
, Late_Expansion
(Aggr
, Typ
, Occ
));
4098 Collect_Initialization_Statements
(Obj
, N
, Node_After
);
4100 Set_No_Initialization
(N
);
4101 Initialize_Discriminants
(N
, Typ
);
4102 end Convert_Aggr_In_Object_Decl
;
4104 -------------------------------------
4105 -- Convert_Array_Aggr_In_Allocator --
4106 -------------------------------------
4108 procedure Convert_Array_Aggr_In_Allocator
4113 Aggr_Code
: List_Id
;
4114 Typ
: constant Entity_Id
:= Etype
(Aggr
);
4115 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
4118 -- The target is an explicit dereference of the allocated object.
4119 -- Generate component assignments to it, as for an aggregate that
4120 -- appears on the right-hand side of an assignment statement.
4123 Build_Array_Aggr_Code
(Aggr
,
4125 Index
=> First_Index
(Typ
),
4127 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
4129 Insert_Actions_After
(Decl
, Aggr_Code
);
4130 end Convert_Array_Aggr_In_Allocator
;
4132 ----------------------------
4133 -- Convert_To_Assignments --
4134 ----------------------------
4136 procedure Convert_To_Assignments
(N
: Node_Id
; Typ
: Entity_Id
) is
4137 Loc
: constant Source_Ptr
:= Sloc
(N
);
4141 Aggr_Code
: List_Id
;
4143 Target_Expr
: Node_Id
;
4144 Parent_Kind
: Node_Kind
;
4145 Unc_Decl
: Boolean := False;
4146 Parent_Node
: Node_Id
;
4149 pragma Assert
(Nkind_In
(N
, N_Aggregate
, N_Extension_Aggregate
));
4150 pragma Assert
(not Is_Static_Dispatch_Table_Aggregate
(N
));
4151 pragma Assert
(Is_Record_Type
(Typ
));
4153 Parent_Node
:= Parent
(N
);
4154 Parent_Kind
:= Nkind
(Parent_Node
);
4156 if Parent_Kind
= N_Qualified_Expression
then
4157 -- Check if we are in an unconstrained declaration because in this
4158 -- case the current delayed expansion mechanism doesn't work when
4159 -- the declared object size depends on the initializing expr.
4161 Parent_Node
:= Parent
(Parent_Node
);
4162 Parent_Kind
:= Nkind
(Parent_Node
);
4164 if Parent_Kind
= N_Object_Declaration
then
4166 not Is_Entity_Name
(Object_Definition
(Parent_Node
))
4167 or else (Nkind
(N
) = N_Aggregate
4170 (Entity
(Object_Definition
(Parent_Node
))))
4171 or else Is_Class_Wide_Type
4172 (Entity
(Object_Definition
(Parent_Node
)));
4176 -- Just set the Delay flag in the cases where the transformation will be
4177 -- done top down from above.
4181 -- Internal aggregate (transformed when expanding the parent)
4183 or else Parent_Kind
= N_Aggregate
4184 or else Parent_Kind
= N_Extension_Aggregate
4185 or else Parent_Kind
= N_Component_Association
4187 -- Allocator (see Convert_Aggr_In_Allocator)
4189 or else Parent_Kind
= N_Allocator
4191 -- Object declaration (see Convert_Aggr_In_Object_Decl)
4193 or else (Parent_Kind
= N_Object_Declaration
and then not Unc_Decl
)
4195 -- Safe assignment (see Convert_Aggr_Assignments). So far only the
4196 -- assignments in init procs are taken into account.
4198 or else (Parent_Kind
= N_Assignment_Statement
4199 and then Inside_Init_Proc
)
4201 -- (Ada 2005) An inherently limited type in a return statement, which
4202 -- will be handled in a build-in-place fashion, and may be rewritten
4203 -- as an extended return and have its own finalization machinery.
4204 -- In the case of a simple return, the aggregate needs to be delayed
4205 -- until the scope for the return statement has been created, so
4206 -- that any finalization chain will be associated with that scope.
4207 -- For extended returns, we delay expansion to avoid the creation
4208 -- of an unwanted transient scope that could result in premature
4209 -- finalization of the return object (which is built in place
4210 -- within the caller's scope).
4212 or else Is_Build_In_Place_Aggregate_Return
(N
)
4214 Set_Expansion_Delayed
(N
);
4218 -- Otherwise, if a transient scope is required, create it now. If we
4219 -- are within an initialization procedure do not create such, because
4220 -- the target of the assignment must not be declared within a local
4221 -- block, and because cleanup will take place on return from the
4222 -- initialization procedure.
4224 -- Should the condition be more restrictive ???
4226 if Requires_Transient_Scope
(Typ
) and then not Inside_Init_Proc
then
4227 Establish_Transient_Scope
(N
, Sec_Stack
=> False);
4230 -- If the aggregate is nonlimited, create a temporary. If it is limited
4231 -- and context is an assignment, this is a subaggregate for an enclosing
4232 -- aggregate being expanded. It must be built in place, so use target of
4233 -- the current assignment.
4235 if Is_Limited_Type
(Typ
)
4236 and then Nkind
(Parent
(N
)) = N_Assignment_Statement
4238 Target_Expr
:= New_Copy_Tree
(Name
(Parent
(N
)));
4239 Insert_Actions
(Parent
(N
),
4240 Build_Record_Aggr_Code
(N
, Typ
, Target_Expr
));
4241 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
4244 Temp
:= Make_Temporary
(Loc
, 'A', N
);
4246 -- If the type inherits unknown discriminants, use the view with
4247 -- known discriminants if available.
4249 if Has_Unknown_Discriminants
(Typ
)
4250 and then Present
(Underlying_Record_View
(Typ
))
4252 T
:= Underlying_Record_View
(Typ
);
4258 Make_Object_Declaration
(Loc
,
4259 Defining_Identifier
=> Temp
,
4260 Object_Definition
=> New_Occurrence_Of
(T
, Loc
));
4262 Set_No_Initialization
(Instr
);
4263 Insert_Action
(N
, Instr
);
4264 Initialize_Discriminants
(Instr
, T
);
4266 Target_Expr
:= New_Occurrence_Of
(Temp
, Loc
);
4267 Aggr_Code
:= Build_Record_Aggr_Code
(N
, T
, Target_Expr
);
4269 -- Save the last assignment statement associated with the aggregate
4270 -- when building a controlled object. This reference is utilized by
4271 -- the finalization machinery when marking an object as successfully
4274 if Needs_Finalization
(T
) then
4275 Set_Last_Aggregate_Assignment
(Temp
, Last
(Aggr_Code
));
4278 Insert_Actions
(N
, Aggr_Code
);
4279 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
4280 Analyze_And_Resolve
(N
, T
);
4282 end Convert_To_Assignments
;
4284 ---------------------------
4285 -- Convert_To_Positional --
4286 ---------------------------
4288 procedure Convert_To_Positional
4290 Max_Others_Replicate
: Nat
:= 5;
4291 Handle_Bit_Packed
: Boolean := False)
4293 Typ
: constant Entity_Id
:= Etype
(N
);
4295 Static_Components
: Boolean := True;
4297 procedure Check_Static_Components
;
4298 -- Check whether all components of the aggregate are compile-time known
4299 -- values, and can be passed as is to the back-end without further
4301 -- An Iterated_Component_Association is treated as non-static, but there
4302 -- are possibilities for optimization here.
4307 Ixb
: Node_Id
) return Boolean;
4308 -- Convert the aggregate into a purely positional form if possible. On
4309 -- entry the bounds of all dimensions are known to be static, and the
4310 -- total number of components is safe enough to expand.
4312 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean;
4313 -- Return True iff the array N is flat (which is not trivial in the case
4314 -- of multidimensional aggregates).
4316 -----------------------------
4317 -- Check_Static_Components --
4318 -----------------------------
4320 -- Could use some comments in this body ???
4322 procedure Check_Static_Components
is
4326 Static_Components
:= True;
4328 if Nkind
(N
) = N_String_Literal
then
4331 elsif Present
(Expressions
(N
)) then
4332 Expr
:= First
(Expressions
(N
));
4333 while Present
(Expr
) loop
4334 if Nkind
(Expr
) /= N_Aggregate
4335 or else not Compile_Time_Known_Aggregate
(Expr
)
4336 or else Expansion_Delayed
(Expr
)
4338 Static_Components
:= False;
4346 if Nkind
(N
) = N_Aggregate
4347 and then Present
(Component_Associations
(N
))
4349 Expr
:= First
(Component_Associations
(N
));
4350 while Present
(Expr
) loop
4351 if Nkind_In
(Expression
(Expr
), N_Integer_Literal
,
4356 elsif Is_Entity_Name
(Expression
(Expr
))
4357 and then Present
(Entity
(Expression
(Expr
)))
4358 and then Ekind
(Entity
(Expression
(Expr
))) =
4359 E_Enumeration_Literal
4363 elsif Nkind
(Expression
(Expr
)) /= N_Aggregate
4364 or else not Compile_Time_Known_Aggregate
(Expression
(Expr
))
4365 or else Expansion_Delayed
(Expression
(Expr
))
4366 or else Nkind
(Expr
) = N_Iterated_Component_Association
4368 Static_Components
:= False;
4375 end Check_Static_Components
;
4384 Ixb
: Node_Id
) return Boolean
4386 Loc
: constant Source_Ptr
:= Sloc
(N
);
4387 Blo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ixb
));
4388 Lo
: constant Node_Id
:= Type_Low_Bound
(Etype
(Ix
));
4389 Hi
: constant Node_Id
:= Type_High_Bound
(Etype
(Ix
));
4393 Others_Present
: Boolean := False;
4396 if Nkind
(Original_Node
(N
)) = N_String_Literal
then
4400 if not Compile_Time_Known_Value
(Lo
)
4401 or else not Compile_Time_Known_Value
(Hi
)
4406 Lov
:= Expr_Value
(Lo
);
4407 Hiv
:= Expr_Value
(Hi
);
4409 -- Check if there is an others choice
4411 if Present
(Component_Associations
(N
)) then
4417 Assoc
:= First
(Component_Associations
(N
));
4418 while Present
(Assoc
) loop
4420 -- If this is a box association, flattening is in general
4421 -- not possible because at this point we cannot tell if the
4422 -- default is static or even exists.
4424 if Box_Present
(Assoc
) then
4427 elsif Nkind
(Assoc
) = N_Iterated_Component_Association
then
4431 Choice
:= First
(Choice_List
(Assoc
));
4433 while Present
(Choice
) loop
4434 if Nkind
(Choice
) = N_Others_Choice
then
4435 Others_Present
:= True;
4446 -- If the low bound is not known at compile time and others is not
4447 -- present we can proceed since the bounds can be obtained from the
4451 or else (not Compile_Time_Known_Value
(Blo
) and then Others_Present
)
4456 -- Determine if set of alternatives is suitable for conversion and
4457 -- build an array containing the values in sequence.
4460 Vals
: array (UI_To_Int
(Lov
) .. UI_To_Int
(Hiv
))
4461 of Node_Id
:= (others => Empty
);
4462 -- The values in the aggregate sorted appropriately
4465 -- Same data as Vals in list form
4468 -- Used to validate Max_Others_Replicate limit
4471 Num
: Int
:= UI_To_Int
(Lov
);
4477 if Present
(Expressions
(N
)) then
4478 Elmt
:= First
(Expressions
(N
));
4479 while Present
(Elmt
) loop
4480 if Nkind
(Elmt
) = N_Aggregate
4481 and then Present
(Next_Index
(Ix
))
4483 not Flatten
(Elmt
, Next_Index
(Ix
), Next_Index
(Ixb
))
4488 Vals
(Num
) := Relocate_Node
(Elmt
);
4495 if No
(Component_Associations
(N
)) then
4499 Elmt
:= First
(Component_Associations
(N
));
4501 if Nkind
(Expression
(Elmt
)) = N_Aggregate
then
4502 if Present
(Next_Index
(Ix
))
4505 (Expression
(Elmt
), Next_Index
(Ix
), Next_Index
(Ixb
))
4511 Component_Loop
: while Present
(Elmt
) loop
4512 Choice
:= First
(Choice_List
(Elmt
));
4513 Choice_Loop
: while Present
(Choice
) loop
4515 -- If we have an others choice, fill in the missing elements
4516 -- subject to the limit established by Max_Others_Replicate.
4518 if Nkind
(Choice
) = N_Others_Choice
then
4521 for J
in Vals
'Range loop
4522 if No
(Vals
(J
)) then
4523 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
4524 Rep_Count
:= Rep_Count
+ 1;
4526 -- Check for maximum others replication. Note that
4527 -- we skip this test if either of the restrictions
4528 -- No_Elaboration_Code or No_Implicit_Loops is
4529 -- active, if this is a preelaborable unit or
4530 -- a predefined unit, or if the unit must be
4531 -- placed in data memory. This also ensures that
4532 -- predefined units get the same level of constant
4533 -- folding in Ada 95 and Ada 2005, where their
4534 -- categorization has changed.
4537 P
: constant Entity_Id
:=
4538 Cunit_Entity
(Current_Sem_Unit
);
4541 -- Check if duplication OK and if so continue
4544 if Restriction_Active
(No_Elaboration_Code
)
4545 or else Restriction_Active
(No_Implicit_Loops
)
4547 (Ekind
(Current_Scope
) = E_Package
4548 and then Static_Elaboration_Desired
4550 or else Is_Preelaborated
(P
)
4551 or else (Ekind
(P
) = E_Package_Body
4553 Is_Preelaborated
(Spec_Entity
(P
)))
4555 Is_Predefined_Unit
(Get_Source_Unit
(P
))
4559 -- If duplication not OK, then we return False
4560 -- if the replication count is too high
4562 elsif Rep_Count
> Max_Others_Replicate
then
4565 -- Continue on if duplication not OK, but the
4566 -- replication count is not excessive.
4575 exit Component_Loop
;
4577 -- Case of a subtype mark, identifier or expanded name
4579 elsif Is_Entity_Name
(Choice
)
4580 and then Is_Type
(Entity
(Choice
))
4582 Lo
:= Type_Low_Bound
(Etype
(Choice
));
4583 Hi
:= Type_High_Bound
(Etype
(Choice
));
4585 -- Case of subtype indication
4587 elsif Nkind
(Choice
) = N_Subtype_Indication
then
4588 Lo
:= Low_Bound
(Range_Expression
(Constraint
(Choice
)));
4589 Hi
:= High_Bound
(Range_Expression
(Constraint
(Choice
)));
4593 elsif Nkind
(Choice
) = N_Range
then
4594 Lo
:= Low_Bound
(Choice
);
4595 Hi
:= High_Bound
(Choice
);
4597 -- Normal subexpression case
4599 else pragma Assert
(Nkind
(Choice
) in N_Subexpr
);
4600 if not Compile_Time_Known_Value
(Choice
) then
4604 Choice_Index
:= UI_To_Int
(Expr_Value
(Choice
));
4606 if Choice_Index
in Vals
'Range then
4607 Vals
(Choice_Index
) :=
4608 New_Copy_Tree
(Expression
(Elmt
));
4611 -- Choice is statically out-of-range, will be
4612 -- rewritten to raise Constraint_Error.
4620 -- Range cases merge with Lo,Hi set
4622 if not Compile_Time_Known_Value
(Lo
)
4624 not Compile_Time_Known_Value
(Hi
)
4629 for J
in UI_To_Int
(Expr_Value
(Lo
)) ..
4630 UI_To_Int
(Expr_Value
(Hi
))
4632 Vals
(J
) := New_Copy_Tree
(Expression
(Elmt
));
4638 end loop Choice_Loop
;
4641 end loop Component_Loop
;
4643 -- If we get here the conversion is possible
4646 for J
in Vals
'Range loop
4647 Append
(Vals
(J
), Vlist
);
4650 Rewrite
(N
, Make_Aggregate
(Loc
, Expressions
=> Vlist
));
4651 Set_Aggregate_Bounds
(N
, Aggregate_Bounds
(Original_Node
(N
)));
4660 function Is_Flat
(N
: Node_Id
; Dims
: Int
) return Boolean is
4667 elsif Nkind
(N
) = N_Aggregate
then
4668 if Present
(Component_Associations
(N
)) then
4672 Elmt
:= First
(Expressions
(N
));
4673 while Present
(Elmt
) loop
4674 if not Is_Flat
(Elmt
, Dims
- 1) then
4688 -- Start of processing for Convert_To_Positional
4691 -- Only convert to positional when generating C in case of an
4692 -- object declaration, this is the only case where aggregates are
4695 if Modify_Tree_For_C
and then not In_Object_Declaration
(N
) then
4699 -- Ada 2005 (AI-287): Do not convert in case of default initialized
4700 -- components because in this case will need to call the corresponding
4703 if Has_Default_Init_Comps
(N
) then
4707 if Is_Flat
(N
, Number_Dimensions
(Typ
)) then
4711 if Is_Bit_Packed_Array
(Typ
) and then not Handle_Bit_Packed
then
4715 -- Do not convert to positional if controlled components are involved
4716 -- since these require special processing
4718 if Has_Controlled_Component
(Typ
) then
4722 Check_Static_Components
;
4724 -- If the size is known, or all the components are static, try to
4725 -- build a fully positional aggregate.
4727 -- The size of the type may not be known for an aggregate with
4728 -- discriminated array components, but if the components are static
4729 -- it is still possible to verify statically that the length is
4730 -- compatible with the upper bound of the type, and therefore it is
4731 -- worth flattening such aggregates as well.
4733 -- For now the back-end expands these aggregates into individual
4734 -- assignments to the target anyway, but it is conceivable that
4735 -- it will eventually be able to treat such aggregates statically???
4737 if Aggr_Size_OK
(N
, Typ
)
4738 and then Flatten
(N
, First_Index
(Typ
), First_Index
(Base_Type
(Typ
)))
4740 if Static_Components
then
4741 Set_Compile_Time_Known_Aggregate
(N
);
4742 Set_Expansion_Delayed
(N
, False);
4745 Analyze_And_Resolve
(N
, Typ
);
4748 -- If Static_Elaboration_Desired has been specified, diagnose aggregates
4749 -- that will still require initialization code.
4751 if (Ekind
(Current_Scope
) = E_Package
4752 and then Static_Elaboration_Desired
(Current_Scope
))
4753 and then Nkind
(Parent
(N
)) = N_Object_Declaration
4759 if Nkind
(N
) = N_Aggregate
and then Present
(Expressions
(N
)) then
4760 Expr
:= First
(Expressions
(N
));
4761 while Present
(Expr
) loop
4762 if Nkind_In
(Expr
, N_Integer_Literal
, N_Real_Literal
)
4764 (Is_Entity_Name
(Expr
)
4765 and then Ekind
(Entity
(Expr
)) = E_Enumeration_Literal
)
4771 ("non-static object requires elaboration code??", N
);
4778 if Present
(Component_Associations
(N
)) then
4779 Error_Msg_N
("object requires elaboration code??", N
);
4784 end Convert_To_Positional
;
4786 ----------------------------
4787 -- Expand_Array_Aggregate --
4788 ----------------------------
4790 -- Array aggregate expansion proceeds as follows:
4792 -- 1. If requested we generate code to perform all the array aggregate
4793 -- bound checks, specifically
4795 -- (a) Check that the index range defined by aggregate bounds is
4796 -- compatible with corresponding index subtype.
4798 -- (b) If an others choice is present check that no aggregate
4799 -- index is outside the bounds of the index constraint.
4801 -- (c) For multidimensional arrays make sure that all subaggregates
4802 -- corresponding to the same dimension have the same bounds.
4804 -- 2. Check for packed array aggregate which can be converted to a
4805 -- constant so that the aggregate disappears completely.
4807 -- 3. Check case of nested aggregate. Generally nested aggregates are
4808 -- handled during the processing of the parent aggregate.
4810 -- 4. Check if the aggregate can be statically processed. If this is the
4811 -- case pass it as is to Gigi. Note that a necessary condition for
4812 -- static processing is that the aggregate be fully positional.
4814 -- 5. If in place aggregate expansion is possible (i.e. no need to create
4815 -- a temporary) then mark the aggregate as such and return. Otherwise
4816 -- create a new temporary and generate the appropriate initialization
4819 procedure Expand_Array_Aggregate
(N
: Node_Id
) is
4820 Loc
: constant Source_Ptr
:= Sloc
(N
);
4822 Typ
: constant Entity_Id
:= Etype
(N
);
4823 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
4824 -- Typ is the correct constrained array subtype of the aggregate
4825 -- Ctyp is the corresponding component type.
4827 Aggr_Dimension
: constant Pos
:= Number_Dimensions
(Typ
);
4828 -- Number of aggregate index dimensions
4830 Aggr_Low
: array (1 .. Aggr_Dimension
) of Node_Id
;
4831 Aggr_High
: array (1 .. Aggr_Dimension
) of Node_Id
;
4832 -- Low and High bounds of the constraint for each aggregate index
4834 Aggr_Index_Typ
: array (1 .. Aggr_Dimension
) of Entity_Id
;
4835 -- The type of each index
4837 In_Place_Assign_OK_For_Declaration
: Boolean := False;
4838 -- True if we are to generate an in place assignment for a declaration
4840 Maybe_In_Place_OK
: Boolean;
4841 -- If the type is neither controlled nor packed and the aggregate
4842 -- is the expression in an assignment, assignment in place may be
4843 -- possible, provided other conditions are met on the LHS.
4845 Others_Present
: array (1 .. Aggr_Dimension
) of Boolean :=
4847 -- If Others_Present (J) is True, then there is an others choice in one
4848 -- of the subaggregates of N at dimension J.
4850 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean;
4851 -- Returns true if an aggregate assignment can be done by the back end
4853 procedure Build_Constrained_Type
(Positional
: Boolean);
4854 -- If the subtype is not static or unconstrained, build a constrained
4855 -- type using the computable sizes of the aggregate and its sub-
4858 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
);
4859 -- Checks that the bounds of Aggr_Bounds are within the bounds defined
4862 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4863 -- Checks that in a multidimensional array aggregate all subaggregates
4864 -- corresponding to the same dimension have the same bounds. Sub_Aggr is
4865 -- an array subaggregate. Dim is the dimension corresponding to the
4868 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4869 -- Computes the values of array Others_Present. Sub_Aggr is the array
4870 -- subaggregate we start the computation from. Dim is the dimension
4871 -- corresponding to the subaggregate.
4873 function In_Place_Assign_OK
return Boolean;
4874 -- Simple predicate to determine whether an aggregate assignment can
4875 -- be done in place, because none of the new values can depend on the
4876 -- components of the target of the assignment.
4878 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
);
4879 -- Checks that if an others choice is present in any subaggregate, no
4880 -- aggregate index is outside the bounds of the index constraint.
4881 -- Sub_Aggr is an array subaggregate. Dim is the dimension corresponding
4882 -- to the subaggregate.
4884 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean;
4885 -- In addition to Maybe_In_Place_OK, in order for an aggregate to be
4886 -- built directly into the target of the assignment it must be free
4889 ------------------------------------
4890 -- Aggr_Assignment_OK_For_Backend --
4891 ------------------------------------
4893 -- Backend processing by Gigi/gcc is possible only if all the following
4894 -- conditions are met:
4896 -- 1. N consists of a single OTHERS choice, possibly recursively
4898 -- 2. The array type is not packed
4900 -- 3. The array type has no atomic components
4902 -- 4. The array type has no null ranges (the purpose of this is to
4903 -- avoid a bogus warning for an out-of-range value).
4905 -- 5. The component type is elementary
4907 -- 6. The component size is Storage_Unit or the value is of the form
4908 -- M * (1 + A**1 + A**2 + .. A**(K-1)) where A = 2**(Storage_Unit)
4909 -- and M in 1 .. A-1. This can also be viewed as K occurrences of
4910 -- the 8-bit value M, concatenated together.
4912 -- The ultimate goal is to generate a call to a fast memset routine
4913 -- specifically optimized for the target.
4915 function Aggr_Assignment_OK_For_Backend
(N
: Node_Id
) return Boolean is
4918 Expr
: Node_Id
:= N
;
4926 -- Recurse as far as possible to find the innermost component type
4929 while Is_Array_Type
(Ctyp
) loop
4930 if Nkind
(Expr
) /= N_Aggregate
4931 or else not Is_Others_Aggregate
(Expr
)
4936 if Present
(Packed_Array_Impl_Type
(Ctyp
)) then
4940 if Has_Atomic_Components
(Ctyp
) then
4944 Index
:= First_Index
(Ctyp
);
4945 while Present
(Index
) loop
4946 Get_Index_Bounds
(Index
, Low
, High
);
4948 if Is_Null_Range
(Low
, High
) then
4955 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4957 for J
in 1 .. Number_Dimensions
(Ctyp
) - 1 loop
4958 if Nkind
(Expr
) /= N_Aggregate
4959 or else not Is_Others_Aggregate
(Expr
)
4964 Expr
:= Expression
(First
(Component_Associations
(Expr
)));
4967 Ctyp
:= Component_Type
(Ctyp
);
4969 if Is_Atomic_Or_VFA
(Ctyp
) then
4974 -- An Iterated_Component_Association involves a loop (in most cases)
4975 -- and is never static.
4977 if Nkind
(Parent
(Expr
)) = N_Iterated_Component_Association
then
4981 -- All elementary types are supported
4983 if not Is_Elementary_Type
(Ctyp
) then
4987 -- However access types need to be dealt with specially
4989 if Is_Access_Type
(Ctyp
) then
4991 -- Fat pointers are rejected as they are not really elementary
4994 if Esize
(Ctyp
) /= System_Address_Size
then
4998 -- The supported expressions are NULL and constants, others are
4999 -- rejected upfront to avoid being analyzed below, which can be
5000 -- problematic for some of them, for example allocators.
5002 if Nkind
(Expr
) /= N_Null
and then not Is_Entity_Name
(Expr
) then
5007 -- The expression needs to be analyzed if True is returned
5009 Analyze_And_Resolve
(Expr
, Ctyp
);
5011 -- The back end uses the Esize as the precision of the type
5013 Nunits
:= UI_To_Int
(Esize
(Ctyp
)) / System_Storage_Unit
;
5019 if not Compile_Time_Known_Value
(Expr
) then
5023 -- The only supported value for floating point is 0.0
5025 if Is_Floating_Point_Type
(Ctyp
) then
5026 return Expr_Value_R
(Expr
) = Ureal_0
;
5029 -- For other types, we can look into the value as an integer
5031 Value
:= Expr_Value
(Expr
);
5033 if Has_Biased_Representation
(Ctyp
) then
5034 Value
:= Value
- Expr_Value
(Type_Low_Bound
(Ctyp
));
5037 -- Values 0 and -1 immediately satisfy the last check
5039 if Value
= Uint_0
or else Value
= Uint_Minus_1
then
5043 -- We need to work with an unsigned value
5046 Value
:= Value
+ 2**(System_Storage_Unit
* Nunits
);
5049 Remainder
:= Value
rem 2**System_Storage_Unit
;
5051 for J
in 1 .. Nunits
- 1 loop
5052 Value
:= Value
/ 2**System_Storage_Unit
;
5054 if Value
rem 2**System_Storage_Unit
/= Remainder
then
5060 end Aggr_Assignment_OK_For_Backend
;
5062 ----------------------------
5063 -- Build_Constrained_Type --
5064 ----------------------------
5066 procedure Build_Constrained_Type
(Positional
: Boolean) is
5067 Loc
: constant Source_Ptr
:= Sloc
(N
);
5068 Agg_Type
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
5071 Typ
: constant Entity_Id
:= Etype
(N
);
5072 Indexes
: constant List_Id
:= New_List
;
5077 -- If the aggregate is purely positional, all its subaggregates
5078 -- have the same size. We collect the dimensions from the first
5079 -- subaggregate at each level.
5084 for D
in 1 .. Number_Dimensions
(Typ
) loop
5085 Sub_Agg
:= First
(Expressions
(Sub_Agg
));
5089 while Present
(Comp
) loop
5096 Low_Bound
=> Make_Integer_Literal
(Loc
, 1),
5097 High_Bound
=> Make_Integer_Literal
(Loc
, Num
)));
5101 -- We know the aggregate type is unconstrained and the aggregate
5102 -- is not processable by the back end, therefore not necessarily
5103 -- positional. Retrieve each dimension bounds (computed earlier).
5105 for D
in 1 .. Number_Dimensions
(Typ
) loop
5108 Low_Bound
=> Aggr_Low
(D
),
5109 High_Bound
=> Aggr_High
(D
)));
5114 Make_Full_Type_Declaration
(Loc
,
5115 Defining_Identifier
=> Agg_Type
,
5117 Make_Constrained_Array_Definition
(Loc
,
5118 Discrete_Subtype_Definitions
=> Indexes
,
5119 Component_Definition
=>
5120 Make_Component_Definition
(Loc
,
5121 Aliased_Present
=> False,
5122 Subtype_Indication
=>
5123 New_Occurrence_Of
(Component_Type
(Typ
), Loc
))));
5125 Insert_Action
(N
, Decl
);
5127 Set_Etype
(N
, Agg_Type
);
5128 Set_Is_Itype
(Agg_Type
);
5129 Freeze_Itype
(Agg_Type
, N
);
5130 end Build_Constrained_Type
;
5136 procedure Check_Bounds
(Aggr_Bounds
: Node_Id
; Index_Bounds
: Node_Id
) is
5143 Cond
: Node_Id
:= Empty
;
5146 Get_Index_Bounds
(Aggr_Bounds
, Aggr_Lo
, Aggr_Hi
);
5147 Get_Index_Bounds
(Index_Bounds
, Ind_Lo
, Ind_Hi
);
5149 -- Generate the following test:
5151 -- [constraint_error when
5152 -- Aggr_Lo <= Aggr_Hi and then
5153 -- (Aggr_Lo < Ind_Lo or else Aggr_Hi > Ind_Hi)]
5155 -- As an optimization try to see if some tests are trivially vacuous
5156 -- because we are comparing an expression against itself.
5158 if Aggr_Lo
= Ind_Lo
and then Aggr_Hi
= Ind_Hi
then
5161 elsif Aggr_Hi
= Ind_Hi
then
5164 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5165 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
));
5167 elsif Aggr_Lo
= Ind_Lo
then
5170 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
5171 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Hi
));
5178 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5179 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Ind_Lo
)),
5183 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
5184 Right_Opnd
=> Duplicate_Subexpr
(Ind_Hi
)));
5187 if Present
(Cond
) then
5192 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5193 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
)),
5195 Right_Opnd
=> Cond
);
5197 Set_Analyzed
(Left_Opnd
(Left_Opnd
(Cond
)), False);
5198 Set_Analyzed
(Right_Opnd
(Left_Opnd
(Cond
)), False);
5200 Make_Raise_Constraint_Error
(Loc
,
5202 Reason
=> CE_Range_Check_Failed
));
5206 ----------------------------
5207 -- Check_Same_Aggr_Bounds --
5208 ----------------------------
5210 procedure Check_Same_Aggr_Bounds
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
5211 Sub_Lo
: constant Node_Id
:= Low_Bound
(Aggregate_Bounds
(Sub_Aggr
));
5212 Sub_Hi
: constant Node_Id
:= High_Bound
(Aggregate_Bounds
(Sub_Aggr
));
5213 -- The bounds of this specific subaggregate
5215 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
5216 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
5217 -- The bounds of the aggregate for this dimension
5219 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
5220 -- The index type for this dimension.xxx
5222 Cond
: Node_Id
:= Empty
;
5227 -- If index checks are on generate the test
5229 -- [constraint_error when
5230 -- Aggr_Lo /= Sub_Lo or else Aggr_Hi /= Sub_Hi]
5232 -- As an optimization try to see if some tests are trivially vacuos
5233 -- because we are comparing an expression against itself. Also for
5234 -- the first dimension the test is trivially vacuous because there
5235 -- is just one aggregate for dimension 1.
5237 if Index_Checks_Suppressed
(Ind_Typ
) then
5240 elsif Dim
= 1 or else (Aggr_Lo
= Sub_Lo
and then Aggr_Hi
= Sub_Hi
)
5244 elsif Aggr_Hi
= Sub_Hi
then
5247 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5248 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
));
5250 elsif Aggr_Lo
= Sub_Lo
then
5253 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Hi
),
5254 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Hi
));
5261 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
),
5262 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Sub_Lo
)),
5266 Left_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
),
5267 Right_Opnd
=> Duplicate_Subexpr
(Sub_Hi
)));
5270 if Present
(Cond
) then
5272 Make_Raise_Constraint_Error
(Loc
,
5274 Reason
=> CE_Length_Check_Failed
));
5277 -- Now look inside the subaggregate to see if there is more work
5279 if Dim
< Aggr_Dimension
then
5281 -- Process positional components
5283 if Present
(Expressions
(Sub_Aggr
)) then
5284 Expr
:= First
(Expressions
(Sub_Aggr
));
5285 while Present
(Expr
) loop
5286 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
5291 -- Process component associations
5293 if Present
(Component_Associations
(Sub_Aggr
)) then
5294 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5295 while Present
(Assoc
) loop
5296 Expr
:= Expression
(Assoc
);
5297 Check_Same_Aggr_Bounds
(Expr
, Dim
+ 1);
5302 end Check_Same_Aggr_Bounds
;
5304 ----------------------------
5305 -- Compute_Others_Present --
5306 ----------------------------
5308 procedure Compute_Others_Present
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
5313 if Present
(Component_Associations
(Sub_Aggr
)) then
5314 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
5316 if Nkind
(First
(Choice_List
(Assoc
))) = N_Others_Choice
then
5317 Others_Present
(Dim
) := True;
5321 -- Now look inside the subaggregate to see if there is more work
5323 if Dim
< Aggr_Dimension
then
5325 -- Process positional components
5327 if Present
(Expressions
(Sub_Aggr
)) then
5328 Expr
:= First
(Expressions
(Sub_Aggr
));
5329 while Present
(Expr
) loop
5330 Compute_Others_Present
(Expr
, Dim
+ 1);
5335 -- Process component associations
5337 if Present
(Component_Associations
(Sub_Aggr
)) then
5338 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5339 while Present
(Assoc
) loop
5340 Expr
:= Expression
(Assoc
);
5341 Compute_Others_Present
(Expr
, Dim
+ 1);
5346 end Compute_Others_Present
;
5348 ------------------------
5349 -- In_Place_Assign_OK --
5350 ------------------------
5352 function In_Place_Assign_OK
return Boolean is
5360 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean;
5361 -- Check recursively that each component of a (sub)aggregate does not
5362 -- depend on the variable being assigned to.
5364 function Safe_Component
(Expr
: Node_Id
) return Boolean;
5365 -- Verify that an expression cannot depend on the variable being
5366 -- assigned to. Room for improvement here (but less than before).
5368 --------------------
5369 -- Safe_Aggregate --
5370 --------------------
5372 function Safe_Aggregate
(Aggr
: Node_Id
) return Boolean is
5376 if Nkind
(Parent
(Aggr
)) = N_Iterated_Component_Association
then
5380 if Present
(Expressions
(Aggr
)) then
5381 Expr
:= First
(Expressions
(Aggr
));
5382 while Present
(Expr
) loop
5383 if Nkind
(Expr
) = N_Aggregate
then
5384 if not Safe_Aggregate
(Expr
) then
5388 elsif not Safe_Component
(Expr
) then
5396 if Present
(Component_Associations
(Aggr
)) then
5397 Expr
:= First
(Component_Associations
(Aggr
));
5398 while Present
(Expr
) loop
5399 if Nkind
(Expression
(Expr
)) = N_Aggregate
then
5400 if not Safe_Aggregate
(Expression
(Expr
)) then
5404 -- If association has a box, no way to determine yet
5405 -- whether default can be assigned in place.
5407 elsif Box_Present
(Expr
) then
5410 elsif not Safe_Component
(Expression
(Expr
)) then
5421 --------------------
5422 -- Safe_Component --
5423 --------------------
5425 function Safe_Component
(Expr
: Node_Id
) return Boolean is
5426 Comp
: Node_Id
:= Expr
;
5428 function Check_Component
(Comp
: Node_Id
) return Boolean;
5429 -- Do the recursive traversal, after copy
5431 ---------------------
5432 -- Check_Component --
5433 ---------------------
5435 function Check_Component
(Comp
: Node_Id
) return Boolean is
5437 if Is_Overloaded
(Comp
) then
5441 return Compile_Time_Known_Value
(Comp
)
5443 or else (Is_Entity_Name
(Comp
)
5444 and then Present
(Entity
(Comp
))
5445 and then No
(Renamed_Object
(Entity
(Comp
))))
5447 or else (Nkind
(Comp
) = N_Attribute_Reference
5448 and then Check_Component
(Prefix
(Comp
)))
5450 or else (Nkind
(Comp
) in N_Binary_Op
5451 and then Check_Component
(Left_Opnd
(Comp
))
5452 and then Check_Component
(Right_Opnd
(Comp
)))
5454 or else (Nkind
(Comp
) in N_Unary_Op
5455 and then Check_Component
(Right_Opnd
(Comp
)))
5457 or else (Nkind
(Comp
) = N_Selected_Component
5458 and then Check_Component
(Prefix
(Comp
)))
5460 or else (Nkind
(Comp
) = N_Unchecked_Type_Conversion
5461 and then Check_Component
(Expression
(Comp
)));
5462 end Check_Component
;
5464 -- Start of processing for Safe_Component
5467 -- If the component appears in an association that may correspond
5468 -- to more than one element, it is not analyzed before expansion
5469 -- into assignments, to avoid side effects. We analyze, but do not
5470 -- resolve the copy, to obtain sufficient entity information for
5471 -- the checks that follow. If component is overloaded we assume
5472 -- an unsafe function call.
5474 if not Analyzed
(Comp
) then
5475 if Is_Overloaded
(Expr
) then
5478 elsif Nkind
(Expr
) = N_Aggregate
5479 and then not Is_Others_Aggregate
(Expr
)
5483 elsif Nkind
(Expr
) = N_Allocator
then
5485 -- For now, too complex to analyze
5490 Comp
:= New_Copy_Tree
(Expr
);
5491 Set_Parent
(Comp
, Parent
(Expr
));
5495 if Nkind
(Comp
) = N_Aggregate
then
5496 return Safe_Aggregate
(Comp
);
5498 return Check_Component
(Comp
);
5502 -- Start of processing for In_Place_Assign_OK
5505 if Present
(Component_Associations
(N
)) then
5507 -- On assignment, sliding can take place, so we cannot do the
5508 -- assignment in place unless the bounds of the aggregate are
5509 -- statically equal to those of the target.
5511 -- If the aggregate is given by an others choice, the bounds are
5512 -- derived from the left-hand side, and the assignment is safe if
5513 -- the expression is.
5515 if Is_Others_Aggregate
(N
) then
5518 (Expression
(First
(Component_Associations
(N
))));
5521 Aggr_In
:= First_Index
(Etype
(N
));
5523 if Nkind
(Parent
(N
)) = N_Assignment_Statement
then
5524 Obj_In
:= First_Index
(Etype
(Name
(Parent
(N
))));
5527 -- Context is an allocator. Check bounds of aggregate against
5528 -- given type in qualified expression.
5530 pragma Assert
(Nkind
(Parent
(Parent
(N
))) = N_Allocator
);
5532 First_Index
(Etype
(Entity
(Subtype_Mark
(Parent
(N
)))));
5535 while Present
(Aggr_In
) loop
5536 Get_Index_Bounds
(Aggr_In
, Aggr_Lo
, Aggr_Hi
);
5537 Get_Index_Bounds
(Obj_In
, Obj_Lo
, Obj_Hi
);
5539 if not Compile_Time_Known_Value
(Aggr_Lo
)
5540 or else not Compile_Time_Known_Value
(Aggr_Hi
)
5541 or else not Compile_Time_Known_Value
(Obj_Lo
)
5542 or else not Compile_Time_Known_Value
(Obj_Hi
)
5543 or else Expr_Value
(Aggr_Lo
) /= Expr_Value
(Obj_Lo
)
5544 or else Expr_Value
(Aggr_Hi
) /= Expr_Value
(Obj_Hi
)
5549 Next_Index
(Aggr_In
);
5550 Next_Index
(Obj_In
);
5554 -- Now check the component values themselves
5556 return Safe_Aggregate
(N
);
5557 end In_Place_Assign_OK
;
5563 procedure Others_Check
(Sub_Aggr
: Node_Id
; Dim
: Pos
) is
5564 Aggr_Lo
: constant Node_Id
:= Aggr_Low
(Dim
);
5565 Aggr_Hi
: constant Node_Id
:= Aggr_High
(Dim
);
5566 -- The bounds of the aggregate for this dimension
5568 Ind_Typ
: constant Entity_Id
:= Aggr_Index_Typ
(Dim
);
5569 -- The index type for this dimension
5571 Need_To_Check
: Boolean := False;
5573 Choices_Lo
: Node_Id
:= Empty
;
5574 Choices_Hi
: Node_Id
:= Empty
;
5575 -- The lowest and highest discrete choices for a named subaggregate
5577 Nb_Choices
: Int
:= -1;
5578 -- The number of discrete non-others choices in this subaggregate
5580 Nb_Elements
: Uint
:= Uint_0
;
5581 -- The number of elements in a positional aggregate
5583 Cond
: Node_Id
:= Empty
;
5590 -- Check if we have an others choice. If we do make sure that this
5591 -- subaggregate contains at least one element in addition to the
5594 if Range_Checks_Suppressed
(Ind_Typ
) then
5595 Need_To_Check
:= False;
5597 elsif Present
(Expressions
(Sub_Aggr
))
5598 and then Present
(Component_Associations
(Sub_Aggr
))
5600 Need_To_Check
:= True;
5602 elsif Present
(Component_Associations
(Sub_Aggr
)) then
5603 Assoc
:= Last
(Component_Associations
(Sub_Aggr
));
5605 if Nkind
(First
(Choice_List
(Assoc
))) /= N_Others_Choice
then
5606 Need_To_Check
:= False;
5609 -- Count the number of discrete choices. Start with -1 because
5610 -- the others choice does not count.
5612 -- Is there some reason we do not use List_Length here ???
5615 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5616 while Present
(Assoc
) loop
5617 Choice
:= First
(Choice_List
(Assoc
));
5618 while Present
(Choice
) loop
5619 Nb_Choices
:= Nb_Choices
+ 1;
5626 -- If there is only an others choice nothing to do
5628 Need_To_Check
:= (Nb_Choices
> 0);
5632 Need_To_Check
:= False;
5635 -- If we are dealing with a positional subaggregate with an others
5636 -- choice then compute the number or positional elements.
5638 if Need_To_Check
and then Present
(Expressions
(Sub_Aggr
)) then
5639 Expr
:= First
(Expressions
(Sub_Aggr
));
5640 Nb_Elements
:= Uint_0
;
5641 while Present
(Expr
) loop
5642 Nb_Elements
:= Nb_Elements
+ 1;
5646 -- If the aggregate contains discrete choices and an others choice
5647 -- compute the smallest and largest discrete choice values.
5649 elsif Need_To_Check
then
5650 Compute_Choices_Lo_And_Choices_Hi
: declare
5652 Table
: Case_Table_Type
(1 .. Nb_Choices
);
5653 -- Used to sort all the different choice values
5660 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5661 while Present
(Assoc
) loop
5662 Choice
:= First
(Choice_List
(Assoc
));
5663 while Present
(Choice
) loop
5664 if Nkind
(Choice
) = N_Others_Choice
then
5668 Get_Index_Bounds
(Choice
, Low
, High
);
5669 Table
(J
).Choice_Lo
:= Low
;
5670 Table
(J
).Choice_Hi
:= High
;
5679 -- Sort the discrete choices
5681 Sort_Case_Table
(Table
);
5683 Choices_Lo
:= Table
(1).Choice_Lo
;
5684 Choices_Hi
:= Table
(Nb_Choices
).Choice_Hi
;
5685 end Compute_Choices_Lo_And_Choices_Hi
;
5688 -- If no others choice in this subaggregate, or the aggregate
5689 -- comprises only an others choice, nothing to do.
5691 if not Need_To_Check
then
5694 -- If we are dealing with an aggregate containing an others choice
5695 -- and positional components, we generate the following test:
5697 -- if Ind_Typ'Pos (Aggr_Lo) + (Nb_Elements - 1) >
5698 -- Ind_Typ'Pos (Aggr_Hi)
5700 -- raise Constraint_Error;
5703 elsif Nb_Elements
> Uint_0
then
5709 Make_Attribute_Reference
(Loc
,
5710 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
5711 Attribute_Name
=> Name_Pos
,
5714 (Duplicate_Subexpr_Move_Checks
(Aggr_Lo
))),
5715 Right_Opnd
=> Make_Integer_Literal
(Loc
, Nb_Elements
- 1)),
5718 Make_Attribute_Reference
(Loc
,
5719 Prefix
=> New_Occurrence_Of
(Ind_Typ
, Loc
),
5720 Attribute_Name
=> Name_Pos
,
5721 Expressions
=> New_List
(
5722 Duplicate_Subexpr_Move_Checks
(Aggr_Hi
))));
5724 -- If we are dealing with an aggregate containing an others choice
5725 -- and discrete choices we generate the following test:
5727 -- [constraint_error when
5728 -- Choices_Lo < Aggr_Lo or else Choices_Hi > Aggr_Hi];
5735 Left_Opnd
=> Duplicate_Subexpr_Move_Checks
(Choices_Lo
),
5736 Right_Opnd
=> Duplicate_Subexpr_Move_Checks
(Aggr_Lo
)),
5740 Left_Opnd
=> Duplicate_Subexpr
(Choices_Hi
),
5741 Right_Opnd
=> Duplicate_Subexpr
(Aggr_Hi
)));
5744 if Present
(Cond
) then
5746 Make_Raise_Constraint_Error
(Loc
,
5748 Reason
=> CE_Length_Check_Failed
));
5749 -- Questionable reason code, shouldn't that be a
5750 -- CE_Range_Check_Failed ???
5753 -- Now look inside the subaggregate to see if there is more work
5755 if Dim
< Aggr_Dimension
then
5757 -- Process positional components
5759 if Present
(Expressions
(Sub_Aggr
)) then
5760 Expr
:= First
(Expressions
(Sub_Aggr
));
5761 while Present
(Expr
) loop
5762 Others_Check
(Expr
, Dim
+ 1);
5767 -- Process component associations
5769 if Present
(Component_Associations
(Sub_Aggr
)) then
5770 Assoc
:= First
(Component_Associations
(Sub_Aggr
));
5771 while Present
(Assoc
) loop
5772 Expr
:= Expression
(Assoc
);
5773 Others_Check
(Expr
, Dim
+ 1);
5780 -------------------------
5781 -- Safe_Left_Hand_Side --
5782 -------------------------
5784 function Safe_Left_Hand_Side
(N
: Node_Id
) return Boolean is
5785 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean;
5786 -- If the left-hand side includes an indexed component, check that
5787 -- the indexes are free of side effects.
5793 function Is_Safe_Index
(Indx
: Node_Id
) return Boolean is
5795 if Is_Entity_Name
(Indx
) then
5798 elsif Nkind
(Indx
) = N_Integer_Literal
then
5801 elsif Nkind
(Indx
) = N_Function_Call
5802 and then Is_Entity_Name
(Name
(Indx
))
5803 and then Has_Pragma_Pure_Function
(Entity
(Name
(Indx
)))
5807 elsif Nkind
(Indx
) = N_Type_Conversion
5808 and then Is_Safe_Index
(Expression
(Indx
))
5817 -- Start of processing for Safe_Left_Hand_Side
5820 if Is_Entity_Name
(N
) then
5823 elsif Nkind_In
(N
, N_Explicit_Dereference
, N_Selected_Component
)
5824 and then Safe_Left_Hand_Side
(Prefix
(N
))
5828 elsif Nkind
(N
) = N_Indexed_Component
5829 and then Safe_Left_Hand_Side
(Prefix
(N
))
5830 and then Is_Safe_Index
(First
(Expressions
(N
)))
5834 elsif Nkind
(N
) = N_Unchecked_Type_Conversion
then
5835 return Safe_Left_Hand_Side
(Expression
(N
));
5840 end Safe_Left_Hand_Side
;
5845 -- Holds the temporary aggregate value
5848 -- Holds the declaration of Tmp
5850 Aggr_Code
: List_Id
;
5851 Parent_Node
: Node_Id
;
5852 Parent_Kind
: Node_Kind
;
5854 -- Start of processing for Expand_Array_Aggregate
5857 -- Do not touch the special aggregates of attributes used for Asm calls
5859 if Is_RTE
(Ctyp
, RE_Asm_Input_Operand
)
5860 or else Is_RTE
(Ctyp
, RE_Asm_Output_Operand
)
5864 -- Do not expand an aggregate for an array type which contains tasks if
5865 -- the aggregate is associated with an unexpanded return statement of a
5866 -- build-in-place function. The aggregate is expanded when the related
5867 -- return statement (rewritten into an extended return) is processed.
5868 -- This delay ensures that any temporaries and initialization code
5869 -- generated for the aggregate appear in the proper return block and
5870 -- use the correct _chain and _master.
5872 elsif Has_Task
(Base_Type
(Etype
(N
)))
5873 and then Nkind
(Parent
(N
)) = N_Simple_Return_Statement
5874 and then Is_Build_In_Place_Function
5875 (Return_Applies_To
(Return_Statement_Entity
(Parent
(N
))))
5879 -- Do not attempt expansion if error already detected. We may reach this
5880 -- point in spite of previous errors when compiling with -gnatq, to
5881 -- force all possible errors (this is the usual ACATS mode).
5883 elsif Error_Posted
(N
) then
5887 -- If the semantic analyzer has determined that aggregate N will raise
5888 -- Constraint_Error at run time, then the aggregate node has been
5889 -- replaced with an N_Raise_Constraint_Error node and we should
5892 pragma Assert
(not Raises_Constraint_Error
(N
));
5896 -- Check that the index range defined by aggregate bounds is
5897 -- compatible with corresponding index subtype.
5899 Index_Compatibility_Check
: declare
5900 Aggr_Index_Range
: Node_Id
:= First_Index
(Typ
);
5901 -- The current aggregate index range
5903 Index_Constraint
: Node_Id
:= First_Index
(Etype
(Typ
));
5904 -- The corresponding index constraint against which we have to
5905 -- check the above aggregate index range.
5908 Compute_Others_Present
(N
, 1);
5910 for J
in 1 .. Aggr_Dimension
loop
5911 -- There is no need to emit a check if an others choice is present
5912 -- for this array aggregate dimension since in this case one of
5913 -- N's subaggregates has taken its bounds from the context and
5914 -- these bounds must have been checked already. In addition all
5915 -- subaggregates corresponding to the same dimension must all have
5916 -- the same bounds (checked in (c) below).
5918 if not Range_Checks_Suppressed
(Etype
(Index_Constraint
))
5919 and then not Others_Present
(J
)
5921 -- We don't use Checks.Apply_Range_Check here because it emits
5922 -- a spurious check. Namely it checks that the range defined by
5923 -- the aggregate bounds is nonempty. But we know this already
5926 Check_Bounds
(Aggr_Index_Range
, Index_Constraint
);
5929 -- Save the low and high bounds of the aggregate index as well as
5930 -- the index type for later use in checks (b) and (c) below.
5932 Aggr_Low
(J
) := Low_Bound
(Aggr_Index_Range
);
5933 Aggr_High
(J
) := High_Bound
(Aggr_Index_Range
);
5935 Aggr_Index_Typ
(J
) := Etype
(Index_Constraint
);
5937 Next_Index
(Aggr_Index_Range
);
5938 Next_Index
(Index_Constraint
);
5940 end Index_Compatibility_Check
;
5944 -- If an others choice is present check that no aggregate index is
5945 -- outside the bounds of the index constraint.
5947 Others_Check
(N
, 1);
5951 -- For multidimensional arrays make sure that all subaggregates
5952 -- corresponding to the same dimension have the same bounds.
5954 if Aggr_Dimension
> 1 then
5955 Check_Same_Aggr_Bounds
(N
, 1);
5960 -- If we have a default component value, or simple initialization is
5961 -- required for the component type, then we replace <> in component
5962 -- associations by the required default value.
5965 Default_Val
: Node_Id
;
5969 if (Present
(Default_Aspect_Component_Value
(Typ
))
5970 or else Needs_Simple_Initialization
(Ctyp
))
5971 and then Present
(Component_Associations
(N
))
5973 Assoc
:= First
(Component_Associations
(N
));
5974 while Present
(Assoc
) loop
5975 if Nkind
(Assoc
) = N_Component_Association
5976 and then Box_Present
(Assoc
)
5978 Set_Box_Present
(Assoc
, False);
5980 if Present
(Default_Aspect_Component_Value
(Typ
)) then
5981 Default_Val
:= Default_Aspect_Component_Value
(Typ
);
5983 Default_Val
:= Get_Simple_Init_Val
(Ctyp
, N
);
5986 Set_Expression
(Assoc
, New_Copy_Tree
(Default_Val
));
5987 Analyze_And_Resolve
(Expression
(Assoc
), Ctyp
);
5997 -- Here we test for is packed array aggregate that we can handle at
5998 -- compile time. If so, return with transformation done. Note that we do
5999 -- this even if the aggregate is nested, because once we have done this
6000 -- processing, there is no more nested aggregate.
6002 if Packed_Array_Aggregate_Handled
(N
) then
6006 -- At this point we try to convert to positional form
6008 if Ekind
(Current_Scope
) = E_Package
6009 and then Static_Elaboration_Desired
(Current_Scope
)
6011 Convert_To_Positional
(N
, Max_Others_Replicate
=> 100);
6013 Convert_To_Positional
(N
);
6016 -- if the result is no longer an aggregate (e.g. it may be a string
6017 -- literal, or a temporary which has the needed value), then we are
6018 -- done, since there is no longer a nested aggregate.
6020 if Nkind
(N
) /= N_Aggregate
then
6023 -- We are also done if the result is an analyzed aggregate, indicating
6024 -- that Convert_To_Positional succeeded and reanalyzed the rewritten
6027 elsif Analyzed
(N
) and then N
/= Original_Node
(N
) then
6031 -- If all aggregate components are compile-time known and the aggregate
6032 -- has been flattened, nothing left to do. The same occurs if the
6033 -- aggregate is used to initialize the components of a statically
6034 -- allocated dispatch table.
6036 if Compile_Time_Known_Aggregate
(N
)
6037 or else Is_Static_Dispatch_Table_Aggregate
(N
)
6039 Set_Expansion_Delayed
(N
, False);
6043 -- Now see if back end processing is possible
6045 if Backend_Processing_Possible
(N
) then
6047 -- If the aggregate is static but the constraints are not, build
6048 -- a static subtype for the aggregate, so that Gigi can place it
6049 -- in static memory. Perform an unchecked_conversion to the non-
6050 -- static type imposed by the context.
6053 Itype
: constant Entity_Id
:= Etype
(N
);
6055 Needs_Type
: Boolean := False;
6058 Index
:= First_Index
(Itype
);
6059 while Present
(Index
) loop
6060 if not Is_OK_Static_Subtype
(Etype
(Index
)) then
6069 Build_Constrained_Type
(Positional
=> True);
6070 Rewrite
(N
, Unchecked_Convert_To
(Itype
, N
));
6080 -- Delay expansion for nested aggregates: it will be taken care of when
6081 -- the parent aggregate is expanded.
6083 Parent_Node
:= Parent
(N
);
6084 Parent_Kind
:= Nkind
(Parent_Node
);
6086 if Parent_Kind
= N_Qualified_Expression
then
6087 Parent_Node
:= Parent
(Parent_Node
);
6088 Parent_Kind
:= Nkind
(Parent_Node
);
6091 if Parent_Kind
= N_Aggregate
6092 or else Parent_Kind
= N_Extension_Aggregate
6093 or else Parent_Kind
= N_Component_Association
6094 or else (Parent_Kind
= N_Object_Declaration
6095 and then Needs_Finalization
(Typ
))
6096 or else (Parent_Kind
= N_Assignment_Statement
6097 and then Inside_Init_Proc
)
6099 if Static_Array_Aggregate
(N
)
6100 or else Compile_Time_Known_Aggregate
(N
)
6102 Set_Expansion_Delayed
(N
, False);
6105 Set_Expansion_Delayed
(N
);
6112 -- Look if in place aggregate expansion is possible
6114 -- For object declarations we build the aggregate in place, unless
6115 -- the array is bit-packed or the component is controlled.
6117 -- For assignments we do the assignment in place if all the component
6118 -- associations have compile-time known values. For other cases we
6119 -- create a temporary. The analysis for safety of on-line assignment
6120 -- is delicate, i.e. we don't know how to do it fully yet ???
6122 -- For allocators we assign to the designated object in place if the
6123 -- aggregate meets the same conditions as other in-place assignments.
6124 -- In this case the aggregate may not come from source but was created
6125 -- for default initialization, e.g. with Initialize_Scalars.
6127 if Requires_Transient_Scope
(Typ
) then
6128 Establish_Transient_Scope
(N
, Sec_Stack
=> False);
6131 if Has_Default_Init_Comps
(N
) then
6132 Maybe_In_Place_OK
:= False;
6134 elsif Is_Bit_Packed_Array
(Typ
)
6135 or else Has_Controlled_Component
(Typ
)
6137 Maybe_In_Place_OK
:= False;
6140 Maybe_In_Place_OK
:=
6141 (Nkind
(Parent
(N
)) = N_Assignment_Statement
6142 and then In_Place_Assign_OK
)
6145 (Nkind
(Parent
(Parent
(N
))) = N_Allocator
6146 and then In_Place_Assign_OK
);
6149 -- If this is an array of tasks, it will be expanded into build-in-place
6150 -- assignments. Build an activation chain for the tasks now.
6152 if Has_Task
(Etype
(N
)) then
6153 Build_Activation_Chain_Entity
(N
);
6156 -- Perform in-place expansion of aggregate in an object declaration.
6157 -- Note: actions generated for the aggregate will be captured in an
6158 -- expression-with-actions statement so that they can be transferred
6159 -- to freeze actions later if there is an address clause for the
6160 -- object. (Note: we don't use a block statement because this would
6161 -- cause generated freeze nodes to be elaborated in the wrong scope).
6163 -- Do not perform in-place expansion for SPARK 05 because aggregates are
6164 -- expected to appear in qualified form. In-place expansion eliminates
6165 -- the qualification and eventually violates this SPARK 05 restiction.
6167 -- Should document the rest of the guards ???
6169 if not Has_Default_Init_Comps
(N
)
6170 and then Comes_From_Source
(Parent_Node
)
6171 and then Parent_Kind
= N_Object_Declaration
6172 and then Present
(Expression
(Parent_Node
))
6174 Must_Slide
(Etype
(Defining_Identifier
(Parent_Node
)), Typ
)
6175 and then not Has_Controlled_Component
(Typ
)
6176 and then not Is_Bit_Packed_Array
(Typ
)
6177 and then not Restriction_Check_Required
(SPARK_05
)
6179 In_Place_Assign_OK_For_Declaration
:= True;
6180 Tmp
:= Defining_Identifier
(Parent_Node
);
6181 Set_No_Initialization
(Parent_Node
);
6182 Set_Expression
(Parent_Node
, Empty
);
6184 -- Set kind and type of the entity, for use in the analysis
6185 -- of the subsequent assignments. If the nominal type is not
6186 -- constrained, build a subtype from the known bounds of the
6187 -- aggregate. If the declaration has a subtype mark, use it,
6188 -- otherwise use the itype of the aggregate.
6190 Set_Ekind
(Tmp
, E_Variable
);
6192 if not Is_Constrained
(Typ
) then
6193 Build_Constrained_Type
(Positional
=> False);
6195 elsif Is_Entity_Name
(Object_Definition
(Parent_Node
))
6196 and then Is_Constrained
(Entity
(Object_Definition
(Parent_Node
)))
6198 Set_Etype
(Tmp
, Entity
(Object_Definition
(Parent_Node
)));
6201 Set_Size_Known_At_Compile_Time
(Typ
, False);
6202 Set_Etype
(Tmp
, Typ
);
6205 elsif Maybe_In_Place_OK
6206 and then Nkind
(Parent
(N
)) = N_Qualified_Expression
6207 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
6209 Set_Expansion_Delayed
(N
);
6212 -- In the remaining cases the aggregate is the RHS of an assignment
6214 elsif Maybe_In_Place_OK
6215 and then Safe_Left_Hand_Side
(Name
(Parent
(N
)))
6217 Tmp
:= Name
(Parent
(N
));
6219 if Etype
(Tmp
) /= Etype
(N
) then
6220 Apply_Length_Check
(N
, Etype
(Tmp
));
6222 if Nkind
(N
) = N_Raise_Constraint_Error
then
6224 -- Static error, nothing further to expand
6230 -- If a slice assignment has an aggregate with a single others_choice,
6231 -- the assignment can be done in place even if bounds are not static,
6232 -- by converting it into a loop over the discrete range of the slice.
6234 elsif Maybe_In_Place_OK
6235 and then Nkind
(Name
(Parent
(N
))) = N_Slice
6236 and then Is_Others_Aggregate
(N
)
6238 Tmp
:= Name
(Parent
(N
));
6240 -- Set type of aggregate to be type of lhs in assignment, in order
6241 -- to suppress redundant length checks.
6243 Set_Etype
(N
, Etype
(Tmp
));
6247 -- In place aggregate expansion is not possible
6250 Maybe_In_Place_OK
:= False;
6251 Tmp
:= Make_Temporary
(Loc
, 'A', N
);
6253 Make_Object_Declaration
(Loc
,
6254 Defining_Identifier
=> Tmp
,
6255 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
));
6256 Set_No_Initialization
(Tmp_Decl
, True);
6258 -- If we are within a loop, the temporary will be pushed on the
6259 -- stack at each iteration. If the aggregate is the expression for an
6260 -- allocator, it will be immediately copied to the heap and can
6261 -- be reclaimed at once. We create a transient scope around the
6262 -- aggregate for this purpose.
6264 if Ekind
(Current_Scope
) = E_Loop
6265 and then Nkind
(Parent
(Parent
(N
))) = N_Allocator
6267 Establish_Transient_Scope
(N
, Sec_Stack
=> False);
6270 Insert_Action
(N
, Tmp_Decl
);
6273 -- Construct and insert the aggregate code. We can safely suppress index
6274 -- checks because this code is guaranteed not to raise CE on index
6275 -- checks. However we should *not* suppress all checks.
6281 if Nkind
(Tmp
) = N_Defining_Identifier
then
6282 Target
:= New_Occurrence_Of
(Tmp
, Loc
);
6285 if Has_Default_Init_Comps
(N
) then
6287 -- Ada 2005 (AI-287): This case has not been analyzed???
6289 raise Program_Error
;
6292 -- Name in assignment is explicit dereference
6294 Target
:= New_Copy
(Tmp
);
6297 -- If we are to generate an in place assignment for a declaration or
6298 -- an assignment statement, and the assignment can be done directly
6299 -- by the back end, then do not expand further.
6301 -- ??? We can also do that if in place expansion is not possible but
6302 -- then we could go into an infinite recursion.
6304 if (In_Place_Assign_OK_For_Declaration
or else Maybe_In_Place_OK
)
6305 and then not CodePeer_Mode
6306 and then not Modify_Tree_For_C
6307 and then not Possible_Bit_Aligned_Component
(Target
)
6308 and then not Is_Possibly_Unaligned_Slice
(Target
)
6309 and then Aggr_Assignment_OK_For_Backend
(N
)
6311 if Maybe_In_Place_OK
then
6317 Make_Assignment_Statement
(Loc
,
6319 Expression
=> New_Copy_Tree
(N
)));
6323 Build_Array_Aggr_Code
(N
,
6325 Index
=> First_Index
(Typ
),
6327 Scalar_Comp
=> Is_Scalar_Type
(Ctyp
));
6330 -- Save the last assignment statement associated with the aggregate
6331 -- when building a controlled object. This reference is utilized by
6332 -- the finalization machinery when marking an object as successfully
6335 if Needs_Finalization
(Typ
)
6336 and then Is_Entity_Name
(Target
)
6337 and then Present
(Entity
(Target
))
6338 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
6340 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
6344 -- If the aggregate is the expression in a declaration, the expanded
6345 -- code must be inserted after it. The defining entity might not come
6346 -- from source if this is part of an inlined body, but the declaration
6349 if Comes_From_Source
(Tmp
)
6351 (Nkind
(Parent
(N
)) = N_Object_Declaration
6352 and then Comes_From_Source
(Parent
(N
))
6353 and then Tmp
= Defining_Entity
(Parent
(N
)))
6356 Node_After
: constant Node_Id
:= Next
(Parent_Node
);
6359 Insert_Actions_After
(Parent_Node
, Aggr_Code
);
6361 if Parent_Kind
= N_Object_Declaration
then
6362 Collect_Initialization_Statements
6363 (Obj
=> Tmp
, N
=> Parent_Node
, Node_After
=> Node_After
);
6368 Insert_Actions
(N
, Aggr_Code
);
6371 -- If the aggregate has been assigned in place, remove the original
6374 if Nkind
(Parent
(N
)) = N_Assignment_Statement
6375 and then Maybe_In_Place_OK
6377 Rewrite
(Parent
(N
), Make_Null_Statement
(Loc
));
6379 elsif Nkind
(Parent
(N
)) /= N_Object_Declaration
6380 or else Tmp
/= Defining_Identifier
(Parent
(N
))
6382 Rewrite
(N
, New_Occurrence_Of
(Tmp
, Loc
));
6383 Analyze_And_Resolve
(N
, Typ
);
6385 end Expand_Array_Aggregate
;
6387 ------------------------
6388 -- Expand_N_Aggregate --
6389 ------------------------
6391 procedure Expand_N_Aggregate
(N
: Node_Id
) is
6393 -- Record aggregate case
6395 if Is_Record_Type
(Etype
(N
)) then
6396 Expand_Record_Aggregate
(N
);
6398 -- Array aggregate case
6401 -- A special case, if we have a string subtype with bounds 1 .. N,
6402 -- where N is known at compile time, and the aggregate is of the
6403 -- form (others => 'x'), with a single choice and no expressions,
6404 -- and N is less than 80 (an arbitrary limit for now), then replace
6405 -- the aggregate by the equivalent string literal (but do not mark
6406 -- it as static since it is not).
6408 -- Note: this entire circuit is redundant with respect to code in
6409 -- Expand_Array_Aggregate that collapses others choices to positional
6410 -- form, but there are two problems with that circuit:
6412 -- a) It is limited to very small cases due to ill-understood
6413 -- interactions with bootstrapping. That limit is removed by
6414 -- use of the No_Implicit_Loops restriction.
6416 -- b) It incorrectly ends up with the resulting expressions being
6417 -- considered static when they are not. For example, the
6418 -- following test should fail:
6420 -- pragma Restrictions (No_Implicit_Loops);
6421 -- package NonSOthers4 is
6422 -- B : constant String (1 .. 6) := (others => 'A');
6423 -- DH : constant String (1 .. 8) := B & "BB";
6425 -- pragma Export (C, X, Link_Name => DH);
6428 -- But it succeeds (DH looks static to pragma Export)
6430 -- To be sorted out ???
6432 if Present
(Component_Associations
(N
)) then
6434 CA
: constant Node_Id
:= First
(Component_Associations
(N
));
6435 MX
: constant := 80;
6438 if Nkind
(First
(Choice_List
(CA
))) = N_Others_Choice
6439 and then Nkind
(Expression
(CA
)) = N_Character_Literal
6440 and then No
(Expressions
(N
))
6443 T
: constant Entity_Id
:= Etype
(N
);
6444 X
: constant Node_Id
:= First_Index
(T
);
6445 EC
: constant Node_Id
:= Expression
(CA
);
6446 CV
: constant Uint
:= Char_Literal_Value
(EC
);
6447 CC
: constant Int
:= UI_To_Int
(CV
);
6450 if Nkind
(X
) = N_Range
6451 and then Compile_Time_Known_Value
(Low_Bound
(X
))
6452 and then Expr_Value
(Low_Bound
(X
)) = 1
6453 and then Compile_Time_Known_Value
(High_Bound
(X
))
6456 Hi
: constant Uint
:= Expr_Value
(High_Bound
(X
));
6462 for J
in 1 .. UI_To_Int
(Hi
) loop
6463 Store_String_Char
(Char_Code
(CC
));
6467 Make_String_Literal
(Sloc
(N
),
6468 Strval
=> End_String
));
6470 if CC
>= Int
(2 ** 16) then
6471 Set_Has_Wide_Wide_Character
(N
);
6472 elsif CC
>= Int
(2 ** 8) then
6473 Set_Has_Wide_Character
(N
);
6476 Analyze_And_Resolve
(N
, T
);
6477 Set_Is_Static_Expression
(N
, False);
6487 -- Not that special case, so normal expansion of array aggregate
6489 Expand_Array_Aggregate
(N
);
6493 when RE_Not_Available
=>
6495 end Expand_N_Aggregate
;
6497 ------------------------------
6498 -- Expand_N_Delta_Aggregate --
6499 ------------------------------
6501 procedure Expand_N_Delta_Aggregate
(N
: Node_Id
) is
6502 Loc
: constant Source_Ptr
:= Sloc
(N
);
6503 Typ
: constant Entity_Id
:= Etype
(N
);
6508 Make_Object_Declaration
(Loc
,
6509 Defining_Identifier
=> Make_Temporary
(Loc
, 'T'),
6510 Object_Definition
=> New_Occurrence_Of
(Typ
, Loc
),
6511 Expression
=> New_Copy_Tree
(Expression
(N
)));
6513 if Is_Array_Type
(Etype
(N
)) then
6514 Expand_Delta_Array_Aggregate
(N
, New_List
(Decl
));
6516 Expand_Delta_Record_Aggregate
(N
, New_List
(Decl
));
6518 end Expand_N_Delta_Aggregate
;
6520 ----------------------------------
6521 -- Expand_Delta_Array_Aggregate --
6522 ----------------------------------
6524 procedure Expand_Delta_Array_Aggregate
(N
: Node_Id
; Deltas
: List_Id
) is
6525 Loc
: constant Source_Ptr
:= Sloc
(N
);
6526 Temp
: constant Entity_Id
:= Defining_Identifier
(First
(Deltas
));
6529 function Generate_Loop
(C
: Node_Id
) return Node_Id
;
6530 -- Generate a loop containing individual component assignments for
6531 -- choices that are ranges, subtype indications, subtype names, and
6532 -- iterated component associations.
6538 function Generate_Loop
(C
: Node_Id
) return Node_Id
is
6539 Sl
: constant Source_Ptr
:= Sloc
(C
);
6543 if Nkind
(Parent
(C
)) = N_Iterated_Component_Association
then
6545 Make_Defining_Identifier
(Loc
,
6546 Chars
=> (Chars
(Defining_Identifier
(Parent
(C
)))));
6548 Ix
:= Make_Temporary
(Sl
, 'I');
6552 Make_Loop_Statement
(Loc
,
6554 Make_Iteration_Scheme
(Sl
,
6555 Loop_Parameter_Specification
=>
6556 Make_Loop_Parameter_Specification
(Sl
,
6557 Defining_Identifier
=> Ix
,
6558 Discrete_Subtype_Definition
=> New_Copy_Tree
(C
))),
6560 Statements
=> New_List
(
6561 Make_Assignment_Statement
(Sl
,
6563 Make_Indexed_Component
(Sl
,
6564 Prefix
=> New_Occurrence_Of
(Temp
, Sl
),
6565 Expressions
=> New_List
(New_Occurrence_Of
(Ix
, Sl
))),
6566 Expression
=> New_Copy_Tree
(Expression
(Assoc
)))),
6567 End_Label
=> Empty
);
6574 -- Start of processing for Expand_Delta_Array_Aggregate
6577 Assoc
:= First
(Component_Associations
(N
));
6578 while Present
(Assoc
) loop
6579 Choice
:= First
(Choice_List
(Assoc
));
6580 if Nkind
(Assoc
) = N_Iterated_Component_Association
then
6581 while Present
(Choice
) loop
6582 Append_To
(Deltas
, Generate_Loop
(Choice
));
6587 while Present
(Choice
) loop
6589 -- Choice can be given by a range, a subtype indication, a
6590 -- subtype name, a scalar value, or an entity.
6592 if Nkind
(Choice
) = N_Range
6593 or else (Is_Entity_Name
(Choice
)
6594 and then Is_Type
(Entity
(Choice
)))
6596 Append_To
(Deltas
, Generate_Loop
(Choice
));
6598 elsif Nkind
(Choice
) = N_Subtype_Indication
then
6600 Generate_Loop
(Range_Expression
(Constraint
(Choice
))));
6604 Make_Assignment_Statement
(Sloc
(Choice
),
6606 Make_Indexed_Component
(Sloc
(Choice
),
6607 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
6608 Expressions
=> New_List
(New_Copy_Tree
(Choice
))),
6609 Expression
=> New_Copy_Tree
(Expression
(Assoc
))));
6619 Insert_Actions
(N
, Deltas
);
6620 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
6621 end Expand_Delta_Array_Aggregate
;
6623 -----------------------------------
6624 -- Expand_Delta_Record_Aggregate --
6625 -----------------------------------
6627 procedure Expand_Delta_Record_Aggregate
(N
: Node_Id
; Deltas
: List_Id
) is
6628 Loc
: constant Source_Ptr
:= Sloc
(N
);
6629 Temp
: constant Entity_Id
:= Defining_Identifier
(First
(Deltas
));
6634 Assoc
:= First
(Component_Associations
(N
));
6636 while Present
(Assoc
) loop
6637 Choice
:= First
(Choice_List
(Assoc
));
6638 while Present
(Choice
) loop
6640 Make_Assignment_Statement
(Sloc
(Choice
),
6642 Make_Selected_Component
(Sloc
(Choice
),
6643 Prefix
=> New_Occurrence_Of
(Temp
, Loc
),
6644 Selector_Name
=> Make_Identifier
(Loc
, Chars
(Choice
))),
6645 Expression
=> New_Copy_Tree
(Expression
(Assoc
))));
6652 Insert_Actions
(N
, Deltas
);
6653 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
6654 end Expand_Delta_Record_Aggregate
;
6656 ----------------------------------
6657 -- Expand_N_Extension_Aggregate --
6658 ----------------------------------
6660 -- If the ancestor part is an expression, add a component association for
6661 -- the parent field. If the type of the ancestor part is not the direct
6662 -- parent of the expected type, build recursively the needed ancestors.
6663 -- If the ancestor part is a subtype_mark, replace aggregate with a
6664 -- declaration for a temporary of the expected type, followed by
6665 -- individual assignments to the given components.
6667 procedure Expand_N_Extension_Aggregate
(N
: Node_Id
) is
6668 A
: constant Node_Id
:= Ancestor_Part
(N
);
6669 Loc
: constant Source_Ptr
:= Sloc
(N
);
6670 Typ
: constant Entity_Id
:= Etype
(N
);
6673 -- If the ancestor is a subtype mark, an init proc must be called
6674 -- on the resulting object which thus has to be materialized in
6677 if Is_Entity_Name
(A
) and then Is_Type
(Entity
(A
)) then
6678 Convert_To_Assignments
(N
, Typ
);
6680 -- The extension aggregate is transformed into a record aggregate
6681 -- of the following form (c1 and c2 are inherited components)
6683 -- (Exp with c3 => a, c4 => b)
6684 -- ==> (c1 => Exp.c1, c2 => Exp.c2, c3 => a, c4 => b)
6689 if Tagged_Type_Expansion
then
6690 Expand_Record_Aggregate
(N
,
6693 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
),
6696 -- No tag is needed in the case of a VM
6699 Expand_Record_Aggregate
(N
, Parent_Expr
=> A
);
6704 when RE_Not_Available
=>
6706 end Expand_N_Extension_Aggregate
;
6708 -----------------------------
6709 -- Expand_Record_Aggregate --
6710 -----------------------------
6712 procedure Expand_Record_Aggregate
6714 Orig_Tag
: Node_Id
:= Empty
;
6715 Parent_Expr
: Node_Id
:= Empty
)
6717 Loc
: constant Source_Ptr
:= Sloc
(N
);
6718 Comps
: constant List_Id
:= Component_Associations
(N
);
6719 Typ
: constant Entity_Id
:= Etype
(N
);
6720 Base_Typ
: constant Entity_Id
:= Base_Type
(Typ
);
6722 Static_Components
: Boolean := True;
6723 -- Flag to indicate whether all components are compile-time known,
6724 -- and the aggregate can be constructed statically and handled by
6725 -- the back-end. Set to False by Component_OK_For_Backend.
6727 procedure Build_Back_End_Aggregate
;
6728 -- Build a proper aggregate to be handled by the back-end
6730 function Compile_Time_Known_Composite_Value
(N
: Node_Id
) return Boolean;
6731 -- Returns true if N is an expression of composite type which can be
6732 -- fully evaluated at compile time without raising constraint error.
6733 -- Such expressions can be passed as is to Gigi without any expansion.
6735 -- This returns true for N_Aggregate with Compile_Time_Known_Aggregate
6736 -- set and constants whose expression is such an aggregate, recursively.
6738 function Component_OK_For_Backend
return Boolean;
6739 -- Check for presence of a component which makes it impossible for the
6740 -- backend to process the aggregate, thus requiring the use of a series
6741 -- of assignment statements. Cases checked for are a nested aggregate
6742 -- needing Late_Expansion, the presence of a tagged component which may
6743 -- need tag adjustment, and a bit unaligned component reference.
6745 -- We also force expansion into assignments if a component is of a
6746 -- mutable type (including a private type with discriminants) because
6747 -- in that case the size of the component to be copied may be smaller
6748 -- than the side of the target, and there is no simple way for gigi
6749 -- to compute the size of the object to be copied.
6751 -- NOTE: This is part of the ongoing work to define precisely the
6752 -- interface between front-end and back-end handling of aggregates.
6753 -- In general it is desirable to pass aggregates as they are to gigi,
6754 -- in order to minimize elaboration code. This is one case where the
6755 -- semantics of Ada complicate the analysis and lead to anomalies in
6756 -- the gcc back-end if the aggregate is not expanded into assignments.
6758 -- NOTE: This sets the global Static_Components to False in most, but
6759 -- not all, cases when it returns False.
6761 function Has_Per_Object_Constraint
(L
: List_Id
) return Boolean;
6762 -- Return True if any element of L has Has_Per_Object_Constraint set.
6763 -- L should be the Choices component of an N_Component_Association.
6765 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean;
6766 -- If any ancestor of the current type is private, the aggregate
6767 -- cannot be built in place. We cannot rely on Has_Private_Ancestor,
6768 -- because it will not be set when type and its parent are in the
6769 -- same scope, and the parent component needs expansion.
6771 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
;
6772 -- For nested aggregates return the ultimate enclosing aggregate; for
6773 -- non-nested aggregates return N.
6775 ------------------------------
6776 -- Build_Back_End_Aggregate --
6777 ------------------------------
6779 procedure Build_Back_End_Aggregate
is
6782 Tag_Value
: Node_Id
;
6785 if Nkind
(N
) = N_Aggregate
then
6787 -- If the aggregate is static and can be handled by the back-end,
6788 -- nothing left to do.
6790 if Static_Components
then
6791 Set_Compile_Time_Known_Aggregate
(N
);
6792 Set_Expansion_Delayed
(N
, False);
6796 -- If no discriminants, nothing special to do
6798 if not Has_Discriminants
(Typ
) then
6801 -- Case of discriminants present
6803 elsif Is_Derived_Type
(Typ
) then
6805 -- For untagged types, non-stored discriminants are replaced with
6806 -- stored discriminants, which are the ones that gigi uses to
6807 -- describe the type and its components.
6809 Generate_Aggregate_For_Derived_Type
: declare
6810 procedure Prepend_Stored_Values
(T
: Entity_Id
);
6811 -- Scan the list of stored discriminants of the type, and add
6812 -- their values to the aggregate being built.
6814 ---------------------------
6815 -- Prepend_Stored_Values --
6816 ---------------------------
6818 procedure Prepend_Stored_Values
(T
: Entity_Id
) is
6820 First_Comp
: Node_Id
:= Empty
;
6823 Discr
:= First_Stored_Discriminant
(T
);
6824 while Present
(Discr
) loop
6826 Make_Component_Association
(Loc
,
6827 Choices
=> New_List
(
6828 New_Occurrence_Of
(Discr
, Loc
)),
6831 (Get_Discriminant_Value
6834 Discriminant_Constraint
(Typ
))));
6836 if No
(First_Comp
) then
6837 Prepend_To
(Component_Associations
(N
), New_Comp
);
6839 Insert_After
(First_Comp
, New_Comp
);
6842 First_Comp
:= New_Comp
;
6843 Next_Stored_Discriminant
(Discr
);
6845 end Prepend_Stored_Values
;
6849 Constraints
: constant List_Id
:= New_List
;
6853 Num_Disc
: Nat
:= 0;
6854 Num_Gird
: Nat
:= 0;
6856 -- Start of processing for Generate_Aggregate_For_Derived_Type
6859 -- Remove the associations for the discriminant of derived type
6862 First_Comp
: Node_Id
;
6865 First_Comp
:= First
(Component_Associations
(N
));
6866 while Present
(First_Comp
) loop
6870 if Ekind
(Entity
(First
(Choices
(Comp
)))) =
6874 Num_Disc
:= Num_Disc
+ 1;
6879 -- Insert stored discriminant associations in the correct
6880 -- order. If there are more stored discriminants than new
6881 -- discriminants, there is at least one new discriminant that
6882 -- constrains more than one of the stored discriminants. In
6883 -- this case we need to construct a proper subtype of the
6884 -- parent type, in order to supply values to all the
6885 -- components. Otherwise there is one-one correspondence
6886 -- between the constraints and the stored discriminants.
6888 Discr
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6889 while Present
(Discr
) loop
6890 Num_Gird
:= Num_Gird
+ 1;
6891 Next_Stored_Discriminant
(Discr
);
6894 -- Case of more stored discriminants than new discriminants
6896 if Num_Gird
> Num_Disc
then
6898 -- Create a proper subtype of the parent type, which is the
6899 -- proper implementation type for the aggregate, and convert
6900 -- it to the intended target type.
6902 Discr
:= First_Stored_Discriminant
(Base_Type
(Typ
));
6903 while Present
(Discr
) loop
6906 (Get_Discriminant_Value
6909 Discriminant_Constraint
(Typ
)));
6911 Append
(New_Comp
, Constraints
);
6912 Next_Stored_Discriminant
(Discr
);
6916 Make_Subtype_Declaration
(Loc
,
6917 Defining_Identifier
=> Make_Temporary
(Loc
, 'T'),
6918 Subtype_Indication
=>
6919 Make_Subtype_Indication
(Loc
,
6921 New_Occurrence_Of
(Etype
(Base_Type
(Typ
)), Loc
),
6923 Make_Index_Or_Discriminant_Constraint
6924 (Loc
, Constraints
)));
6926 Insert_Action
(N
, Decl
);
6927 Prepend_Stored_Values
(Base_Type
(Typ
));
6929 Set_Etype
(N
, Defining_Identifier
(Decl
));
6932 Rewrite
(N
, Unchecked_Convert_To
(Typ
, N
));
6935 -- Case where we do not have fewer new discriminants than
6936 -- stored discriminants, so in this case we can simply use the
6937 -- stored discriminants of the subtype.
6940 Prepend_Stored_Values
(Typ
);
6942 end Generate_Aggregate_For_Derived_Type
;
6945 if Is_Tagged_Type
(Typ
) then
6947 -- In the tagged case, _parent and _tag component must be created
6949 -- Reset Null_Present unconditionally. Tagged records always have
6950 -- at least one field (the tag or the parent).
6952 Set_Null_Record_Present
(N
, False);
6954 -- When the current aggregate comes from the expansion of an
6955 -- extension aggregate, the parent expr is replaced by an
6956 -- aggregate formed by selected components of this expr.
6958 if Present
(Parent_Expr
) and then Is_Empty_List
(Comps
) then
6959 Comp
:= First_Component_Or_Discriminant
(Typ
);
6960 while Present
(Comp
) loop
6962 -- Skip all expander-generated components
6964 if not Comes_From_Source
(Original_Record_Component
(Comp
))
6970 Make_Selected_Component
(Loc
,
6972 Unchecked_Convert_To
(Typ
,
6973 Duplicate_Subexpr
(Parent_Expr
, True)),
6974 Selector_Name
=> New_Occurrence_Of
(Comp
, Loc
));
6977 Make_Component_Association
(Loc
,
6978 Choices
=> New_List
(
6979 New_Occurrence_Of
(Comp
, Loc
)),
6980 Expression
=> New_Comp
));
6982 Analyze_And_Resolve
(New_Comp
, Etype
(Comp
));
6985 Next_Component_Or_Discriminant
(Comp
);
6989 -- Compute the value for the Tag now, if the type is a root it
6990 -- will be included in the aggregate right away, otherwise it will
6991 -- be propagated to the parent aggregate.
6993 if Present
(Orig_Tag
) then
6994 Tag_Value
:= Orig_Tag
;
6996 elsif not Tagged_Type_Expansion
then
7002 (Node
(First_Elmt
(Access_Disp_Table
(Typ
))), Loc
);
7005 -- For a derived type, an aggregate for the parent is formed with
7006 -- all the inherited components.
7008 if Is_Derived_Type
(Typ
) then
7010 First_Comp
: Node_Id
;
7011 Parent_Comps
: List_Id
;
7012 Parent_Aggr
: Node_Id
;
7013 Parent_Name
: Node_Id
;
7016 -- Remove the inherited component association from the
7017 -- aggregate and store them in the parent aggregate
7019 First_Comp
:= First
(Component_Associations
(N
));
7020 Parent_Comps
:= New_List
;
7021 while Present
(First_Comp
)
7023 Scope
(Original_Record_Component
7024 (Entity
(First
(Choices
(First_Comp
))))) /=
7030 Append
(Comp
, Parent_Comps
);
7034 Make_Aggregate
(Loc
,
7035 Component_Associations
=> Parent_Comps
);
7036 Set_Etype
(Parent_Aggr
, Etype
(Base_Type
(Typ
)));
7038 -- Find the _parent component
7040 Comp
:= First_Component
(Typ
);
7041 while Chars
(Comp
) /= Name_uParent
loop
7042 Comp
:= Next_Component
(Comp
);
7045 Parent_Name
:= New_Occurrence_Of
(Comp
, Loc
);
7047 -- Insert the parent aggregate
7049 Prepend_To
(Component_Associations
(N
),
7050 Make_Component_Association
(Loc
,
7051 Choices
=> New_List
(Parent_Name
),
7052 Expression
=> Parent_Aggr
));
7054 -- Expand recursively the parent propagating the right Tag
7056 Expand_Record_Aggregate
7057 (Parent_Aggr
, Tag_Value
, Parent_Expr
);
7059 -- The ancestor part may be a nested aggregate that has
7060 -- delayed expansion: recheck now.
7062 if not Component_OK_For_Backend
then
7063 Convert_To_Assignments
(N
, Typ
);
7067 -- For a root type, the tag component is added (unless compiling
7068 -- for the VMs, where tags are implicit).
7070 elsif Tagged_Type_Expansion
then
7072 Tag_Name
: constant Node_Id
:=
7074 (First_Tag_Component
(Typ
), Loc
);
7075 Typ_Tag
: constant Entity_Id
:= RTE
(RE_Tag
);
7076 Conv_Node
: constant Node_Id
:=
7077 Unchecked_Convert_To
(Typ_Tag
, Tag_Value
);
7080 Set_Etype
(Conv_Node
, Typ_Tag
);
7081 Prepend_To
(Component_Associations
(N
),
7082 Make_Component_Association
(Loc
,
7083 Choices
=> New_List
(Tag_Name
),
7084 Expression
=> Conv_Node
));
7088 end Build_Back_End_Aggregate
;
7090 ----------------------------------------
7091 -- Compile_Time_Known_Composite_Value --
7092 ----------------------------------------
7094 function Compile_Time_Known_Composite_Value
7095 (N
: Node_Id
) return Boolean
7098 -- If we have an entity name, then see if it is the name of a
7099 -- constant and if so, test the corresponding constant value.
7101 if Is_Entity_Name
(N
) then
7103 E
: constant Entity_Id
:= Entity
(N
);
7106 if Ekind
(E
) /= E_Constant
then
7109 V
:= Constant_Value
(E
);
7111 and then Compile_Time_Known_Composite_Value
(V
);
7115 -- We have a value, see if it is compile time known
7118 if Nkind
(N
) = N_Aggregate
then
7119 return Compile_Time_Known_Aggregate
(N
);
7122 -- All other types of values are not known at compile time
7127 end Compile_Time_Known_Composite_Value
;
7129 ------------------------------
7130 -- Component_OK_For_Backend --
7131 ------------------------------
7133 function Component_OK_For_Backend
return Boolean is
7143 while Present
(C
) loop
7145 -- If the component has box initialization, expansion is needed
7146 -- and component is not ready for backend.
7148 if Box_Present
(C
) then
7152 if Nkind
(Expression
(C
)) = N_Qualified_Expression
then
7153 Expr_Q
:= Expression
(Expression
(C
));
7155 Expr_Q
:= Expression
(C
);
7158 -- Return False if the aggregate has any associations for tagged
7159 -- components that may require tag adjustment.
7161 -- These are cases where the source expression may have a tag that
7162 -- could differ from the component tag (e.g., can occur for type
7163 -- conversions and formal parameters). (Tag adjustment not needed
7164 -- if Tagged_Type_Expansion because object tags are implicit in
7167 if Is_Tagged_Type
(Etype
(Expr_Q
))
7168 and then (Nkind
(Expr_Q
) = N_Type_Conversion
7169 or else (Is_Entity_Name
(Expr_Q
)
7171 Ekind
(Entity
(Expr_Q
)) in Formal_Kind
))
7172 and then Tagged_Type_Expansion
7174 Static_Components
:= False;
7177 elsif Is_Delayed_Aggregate
(Expr_Q
) then
7178 Static_Components
:= False;
7181 elsif Possible_Bit_Aligned_Component
(Expr_Q
) then
7182 Static_Components
:= False;
7185 elsif Modify_Tree_For_C
7186 and then Nkind
(C
) = N_Component_Association
7187 and then Has_Per_Object_Constraint
(Choices
(C
))
7189 Static_Components
:= False;
7192 elsif Modify_Tree_For_C
7193 and then Nkind
(Expr_Q
) = N_Identifier
7194 and then Is_Array_Type
(Etype
(Expr_Q
))
7196 Static_Components
:= False;
7199 elsif Modify_Tree_For_C
7200 and then Nkind
(Expr_Q
) = N_Type_Conversion
7201 and then Is_Array_Type
(Etype
(Expr_Q
))
7203 Static_Components
:= False;
7207 if Is_Elementary_Type
(Etype
(Expr_Q
)) then
7208 if not Compile_Time_Known_Value
(Expr_Q
) then
7209 Static_Components
:= False;
7212 elsif not Compile_Time_Known_Composite_Value
(Expr_Q
) then
7213 Static_Components
:= False;
7215 if Is_Private_Type
(Etype
(Expr_Q
))
7216 and then Has_Discriminants
(Etype
(Expr_Q
))
7226 end Component_OK_For_Backend
;
7228 -------------------------------
7229 -- Has_Per_Object_Constraint --
7230 -------------------------------
7232 function Has_Per_Object_Constraint
(L
: List_Id
) return Boolean is
7233 N
: Node_Id
:= First
(L
);
7235 while Present
(N
) loop
7236 if Is_Entity_Name
(N
)
7237 and then Present
(Entity
(N
))
7238 and then Has_Per_Object_Constraint
(Entity
(N
))
7247 end Has_Per_Object_Constraint
;
7249 -----------------------------------
7250 -- Has_Visible_Private_Ancestor --
7251 -----------------------------------
7253 function Has_Visible_Private_Ancestor
(Id
: E
) return Boolean is
7254 R
: constant Entity_Id
:= Root_Type
(Id
);
7255 T1
: Entity_Id
:= Id
;
7259 if Is_Private_Type
(T1
) then
7269 end Has_Visible_Private_Ancestor
;
7271 -------------------------
7272 -- Top_Level_Aggregate --
7273 -------------------------
7275 function Top_Level_Aggregate
(N
: Node_Id
) return Node_Id
is
7280 while Present
(Parent
(Aggr
))
7281 and then Nkind_In
(Parent
(Aggr
), N_Aggregate
,
7282 N_Component_Association
)
7284 Aggr
:= Parent
(Aggr
);
7288 end Top_Level_Aggregate
;
7292 Top_Level_Aggr
: constant Node_Id
:= Top_Level_Aggregate
(N
);
7294 -- Start of processing for Expand_Record_Aggregate
7297 -- If the aggregate is to be assigned to an atomic/VFA variable, we have
7298 -- to prevent a piecemeal assignment even if the aggregate is to be
7299 -- expanded. We create a temporary for the aggregate, and assign the
7300 -- temporary instead, so that the back end can generate an atomic move
7303 if Is_Atomic_VFA_Aggregate
(N
) then
7306 -- No special management required for aggregates used to initialize
7307 -- statically allocated dispatch tables
7309 elsif Is_Static_Dispatch_Table_Aggregate
(N
) then
7313 -- Ada 2005 (AI-318-2): We need to convert to assignments if components
7314 -- are build-in-place function calls. The assignments will each turn
7315 -- into a build-in-place function call. If components are all static,
7316 -- we can pass the aggregate to the back end regardless of limitedness.
7318 -- Extension aggregates, aggregates in extended return statements, and
7319 -- aggregates for C++ imported types must be expanded.
7321 if Ada_Version
>= Ada_2005
and then Is_Limited_View
(Typ
) then
7322 if not Nkind_In
(Parent
(N
), N_Component_Association
,
7323 N_Object_Declaration
)
7325 Convert_To_Assignments
(N
, Typ
);
7327 elsif Nkind
(N
) = N_Extension_Aggregate
7328 or else Convention
(Typ
) = Convention_CPP
7330 Convert_To_Assignments
(N
, Typ
);
7332 elsif not Size_Known_At_Compile_Time
(Typ
)
7333 or else not Component_OK_For_Backend
7334 or else not Static_Components
7336 Convert_To_Assignments
(N
, Typ
);
7338 -- In all other cases, build a proper aggregate to be handled by
7342 Build_Back_End_Aggregate
;
7345 -- Gigi doesn't properly handle temporaries of variable size so we
7346 -- generate it in the front-end
7348 elsif not Size_Known_At_Compile_Time
(Typ
)
7349 and then Tagged_Type_Expansion
7351 Convert_To_Assignments
(N
, Typ
);
7353 -- An aggregate used to initialize a controlled object must be turned
7354 -- into component assignments as the components themselves may require
7355 -- finalization actions such as adjustment.
7357 elsif Needs_Finalization
(Typ
) then
7358 Convert_To_Assignments
(N
, Typ
);
7360 -- Ada 2005 (AI-287): In case of default initialized components we
7361 -- convert the aggregate into assignments.
7363 elsif Has_Default_Init_Comps
(N
) then
7364 Convert_To_Assignments
(N
, Typ
);
7368 elsif not Component_OK_For_Backend
then
7369 Convert_To_Assignments
(N
, Typ
);
7371 -- If an ancestor is private, some components are not inherited and we
7372 -- cannot expand into a record aggregate.
7374 elsif Has_Visible_Private_Ancestor
(Typ
) then
7375 Convert_To_Assignments
(N
, Typ
);
7377 -- ??? The following was done to compile fxacc00.ads in the ACVCs. Gigi
7378 -- is not able to handle the aggregate for Late_Request.
7380 elsif Is_Tagged_Type
(Typ
) and then Has_Discriminants
(Typ
) then
7381 Convert_To_Assignments
(N
, Typ
);
7383 -- If the tagged types covers interface types we need to initialize all
7384 -- hidden components containing pointers to secondary dispatch tables.
7386 elsif Is_Tagged_Type
(Typ
) and then Has_Interfaces
(Typ
) then
7387 Convert_To_Assignments
(N
, Typ
);
7389 -- If some components are mutable, the size of the aggregate component
7390 -- may be distinct from the default size of the type component, so
7391 -- we need to expand to insure that the back-end copies the proper
7392 -- size of the data. However, if the aggregate is the initial value of
7393 -- a constant, the target is immutable and might be built statically
7394 -- if components are appropriate.
7396 elsif Has_Mutable_Components
(Typ
)
7398 (Nkind
(Parent
(Top_Level_Aggr
)) /= N_Object_Declaration
7399 or else not Constant_Present
(Parent
(Top_Level_Aggr
))
7400 or else not Static_Components
)
7402 Convert_To_Assignments
(N
, Typ
);
7404 -- If the type involved has bit aligned components, then we are not sure
7405 -- that the back end can handle this case correctly.
7407 elsif Type_May_Have_Bit_Aligned_Components
(Typ
) then
7408 Convert_To_Assignments
(N
, Typ
);
7410 -- When generating C, only generate an aggregate when declaring objects
7411 -- since C does not support aggregates in e.g. assignment statements.
7413 elsif Modify_Tree_For_C
and then not In_Object_Declaration
(N
) then
7414 Convert_To_Assignments
(N
, Typ
);
7416 -- In all other cases, build a proper aggregate to be handled by gigi
7419 Build_Back_End_Aggregate
;
7421 end Expand_Record_Aggregate
;
7423 ----------------------------
7424 -- Has_Default_Init_Comps --
7425 ----------------------------
7427 function Has_Default_Init_Comps
(N
: Node_Id
) return Boolean is
7428 Comps
: constant List_Id
:= Component_Associations
(N
);
7433 pragma Assert
(Nkind_In
(N
, N_Aggregate
, N_Extension_Aggregate
));
7439 if Has_Self_Reference
(N
) then
7443 -- Check if any direct component has default initialized components
7446 while Present
(C
) loop
7447 if Box_Present
(C
) then
7454 -- Recursive call in case of aggregate expression
7457 while Present
(C
) loop
7458 Expr
:= Expression
(C
);
7461 and then Nkind_In
(Expr
, N_Aggregate
, N_Extension_Aggregate
)
7462 and then Has_Default_Init_Comps
(Expr
)
7471 end Has_Default_Init_Comps
;
7473 ----------------------------------------
7474 -- Is_Build_In_Place_Aggregate_Return --
7475 ----------------------------------------
7477 function Is_Build_In_Place_Aggregate_Return
(N
: Node_Id
) return Boolean is
7478 P
: Node_Id
:= Parent
(N
);
7481 while Nkind
(P
) = N_Qualified_Expression
loop
7485 if Nkind
(P
) = N_Simple_Return_Statement
then
7488 elsif Nkind
(Parent
(P
)) = N_Extended_Return_Statement
then
7496 Is_Build_In_Place_Function
7497 (Return_Applies_To
(Return_Statement_Entity
(P
)));
7498 end Is_Build_In_Place_Aggregate_Return
;
7500 --------------------------
7501 -- Is_Delayed_Aggregate --
7502 --------------------------
7504 function Is_Delayed_Aggregate
(N
: Node_Id
) return Boolean is
7505 Node
: Node_Id
:= N
;
7506 Kind
: Node_Kind
:= Nkind
(Node
);
7509 if Kind
= N_Qualified_Expression
then
7510 Node
:= Expression
(Node
);
7511 Kind
:= Nkind
(Node
);
7514 if not Nkind_In
(Kind
, N_Aggregate
, N_Extension_Aggregate
) then
7517 return Expansion_Delayed
(Node
);
7519 end Is_Delayed_Aggregate
;
7521 ---------------------------
7522 -- In_Object_Declaration --
7523 ---------------------------
7525 function In_Object_Declaration
(N
: Node_Id
) return Boolean is
7526 P
: Node_Id
:= Parent
(N
);
7528 while Present
(P
) loop
7529 if Nkind
(P
) = N_Object_Declaration
then
7537 end In_Object_Declaration
;
7539 ----------------------------------------
7540 -- Is_Static_Dispatch_Table_Aggregate --
7541 ----------------------------------------
7543 function Is_Static_Dispatch_Table_Aggregate
(N
: Node_Id
) return Boolean is
7544 Typ
: constant Entity_Id
:= Base_Type
(Etype
(N
));
7547 return Building_Static_Dispatch_Tables
7548 and then Tagged_Type_Expansion
7549 and then RTU_Loaded
(Ada_Tags
)
7551 -- Avoid circularity when rebuilding the compiler
7553 and then Cunit_Entity
(Get_Source_Unit
(N
)) /= RTU_Entity
(Ada_Tags
)
7554 and then (Typ
= RTE
(RE_Dispatch_Table_Wrapper
)
7556 Typ
= RTE
(RE_Address_Array
)
7558 Typ
= RTE
(RE_Type_Specific_Data
)
7560 Typ
= RTE
(RE_Tag_Table
)
7562 (RTE_Available
(RE_Interface_Data
)
7563 and then Typ
= RTE
(RE_Interface_Data
))
7565 (RTE_Available
(RE_Interfaces_Array
)
7566 and then Typ
= RTE
(RE_Interfaces_Array
))
7568 (RTE_Available
(RE_Interface_Data_Element
)
7569 and then Typ
= RTE
(RE_Interface_Data_Element
)));
7570 end Is_Static_Dispatch_Table_Aggregate
;
7572 -----------------------------
7573 -- Is_Two_Dim_Packed_Array --
7574 -----------------------------
7576 function Is_Two_Dim_Packed_Array
(Typ
: Entity_Id
) return Boolean is
7577 C
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
7579 return Number_Dimensions
(Typ
) = 2
7580 and then Is_Bit_Packed_Array
(Typ
)
7581 and then (C
= 1 or else C
= 2 or else C
= 4);
7582 end Is_Two_Dim_Packed_Array
;
7584 --------------------
7585 -- Late_Expansion --
7586 --------------------
7588 function Late_Expansion
7591 Target
: Node_Id
) return List_Id
7593 Aggr_Code
: List_Id
;
7596 if Is_Array_Type
(Etype
(N
)) then
7598 Build_Array_Aggr_Code
7600 Ctype
=> Component_Type
(Etype
(N
)),
7601 Index
=> First_Index
(Typ
),
7603 Scalar_Comp
=> Is_Scalar_Type
(Component_Type
(Typ
)),
7604 Indexes
=> No_List
);
7606 -- Directly or indirectly (e.g. access protected procedure) a record
7609 Aggr_Code
:= Build_Record_Aggr_Code
(N
, Typ
, Target
);
7612 -- Save the last assignment statement associated with the aggregate
7613 -- when building a controlled object. This reference is utilized by
7614 -- the finalization machinery when marking an object as successfully
7617 if Needs_Finalization
(Typ
)
7618 and then Is_Entity_Name
(Target
)
7619 and then Present
(Entity
(Target
))
7620 and then Ekind_In
(Entity
(Target
), E_Constant
, E_Variable
)
7622 Set_Last_Aggregate_Assignment
(Entity
(Target
), Last
(Aggr_Code
));
7628 ----------------------------------
7629 -- Make_OK_Assignment_Statement --
7630 ----------------------------------
7632 function Make_OK_Assignment_Statement
7635 Expression
: Node_Id
) return Node_Id
7638 Set_Assignment_OK
(Name
);
7639 return Make_Assignment_Statement
(Sloc
, Name
, Expression
);
7640 end Make_OK_Assignment_Statement
;
7642 -----------------------
7643 -- Number_Of_Choices --
7644 -----------------------
7646 function Number_Of_Choices
(N
: Node_Id
) return Nat
is
7650 Nb_Choices
: Nat
:= 0;
7653 if Present
(Expressions
(N
)) then
7657 Assoc
:= First
(Component_Associations
(N
));
7658 while Present
(Assoc
) loop
7659 Choice
:= First
(Choice_List
(Assoc
));
7660 while Present
(Choice
) loop
7661 if Nkind
(Choice
) /= N_Others_Choice
then
7662 Nb_Choices
:= Nb_Choices
+ 1;
7672 end Number_Of_Choices
;
7674 ------------------------------------
7675 -- Packed_Array_Aggregate_Handled --
7676 ------------------------------------
7678 -- The current version of this procedure will handle at compile time
7679 -- any array aggregate that meets these conditions:
7681 -- One and two dimensional, bit packed
7682 -- Underlying packed type is modular type
7683 -- Bounds are within 32-bit Int range
7684 -- All bounds and values are static
7686 -- Note: for now, in the 2-D case, we only handle component sizes of
7687 -- 1, 2, 4 (cases where an integral number of elements occupies a byte).
7689 function Packed_Array_Aggregate_Handled
(N
: Node_Id
) return Boolean is
7690 Loc
: constant Source_Ptr
:= Sloc
(N
);
7691 Typ
: constant Entity_Id
:= Etype
(N
);
7692 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
7694 Not_Handled
: exception;
7695 -- Exception raised if this aggregate cannot be handled
7698 -- Handle one- or two dimensional bit packed array
7700 if not Is_Bit_Packed_Array
(Typ
)
7701 or else Number_Dimensions
(Typ
) > 2
7706 -- If two-dimensional, check whether it can be folded, and transformed
7707 -- into a one-dimensional aggregate for the Packed_Array_Impl_Type of
7708 -- the original type.
7710 if Number_Dimensions
(Typ
) = 2 then
7711 return Two_Dim_Packed_Array_Handled
(N
);
7714 if not Is_Modular_Integer_Type
(Packed_Array_Impl_Type
(Typ
)) then
7718 if not Is_Scalar_Type
(Component_Type
(Typ
))
7719 and then Has_Non_Standard_Rep
(Component_Type
(Typ
))
7725 Csiz
: constant Nat
:= UI_To_Int
(Component_Size
(Typ
));
7729 -- Bounds of index type
7733 -- Values of bounds if compile time known
7735 function Get_Component_Val
(N
: Node_Id
) return Uint
;
7736 -- Given a expression value N of the component type Ctyp, returns a
7737 -- value of Csiz (component size) bits representing this value. If
7738 -- the value is non-static or any other reason exists why the value
7739 -- cannot be returned, then Not_Handled is raised.
7741 -----------------------
7742 -- Get_Component_Val --
7743 -----------------------
7745 function Get_Component_Val
(N
: Node_Id
) return Uint
is
7749 -- We have to analyze the expression here before doing any further
7750 -- processing here. The analysis of such expressions is deferred
7751 -- till expansion to prevent some problems of premature analysis.
7753 Analyze_And_Resolve
(N
, Ctyp
);
7755 -- Must have a compile time value. String literals have to be
7756 -- converted into temporaries as well, because they cannot easily
7757 -- be converted into their bit representation.
7759 if not Compile_Time_Known_Value
(N
)
7760 or else Nkind
(N
) = N_String_Literal
7765 Val
:= Expr_Rep_Value
(N
);
7767 -- Adjust for bias, and strip proper number of bits
7769 if Has_Biased_Representation
(Ctyp
) then
7770 Val
:= Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
7773 return Val
mod Uint_2
** Csiz
;
7774 end Get_Component_Val
;
7776 -- Here we know we have a one dimensional bit packed array
7779 Get_Index_Bounds
(First_Index
(Typ
), Lo
, Hi
);
7781 -- Cannot do anything if bounds are dynamic
7783 if not Compile_Time_Known_Value
(Lo
)
7785 not Compile_Time_Known_Value
(Hi
)
7790 -- Or are silly out of range of int bounds
7792 Lob
:= Expr_Value
(Lo
);
7793 Hib
:= Expr_Value
(Hi
);
7795 if not UI_Is_In_Int_Range
(Lob
)
7797 not UI_Is_In_Int_Range
(Hib
)
7802 -- At this stage we have a suitable aggregate for handling at compile
7803 -- time. The only remaining checks are that the values of expressions
7804 -- in the aggregate are compile-time known (checks are performed by
7805 -- Get_Component_Val), and that any subtypes or ranges are statically
7808 -- If the aggregate is not fully positional at this stage, then
7809 -- convert it to positional form. Either this will fail, in which
7810 -- case we can do nothing, or it will succeed, in which case we have
7811 -- succeeded in handling the aggregate and transforming it into a
7812 -- modular value, or it will stay an aggregate, in which case we
7813 -- have failed to create a packed value for it.
7815 if Present
(Component_Associations
(N
)) then
7816 Convert_To_Positional
7817 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
7818 return Nkind
(N
) /= N_Aggregate
;
7821 -- Otherwise we are all positional, so convert to proper value
7824 Lov
: constant Int
:= UI_To_Int
(Lob
);
7825 Hiv
: constant Int
:= UI_To_Int
(Hib
);
7827 Len
: constant Nat
:= Int
'Max (0, Hiv
- Lov
+ 1);
7828 -- The length of the array (number of elements)
7830 Aggregate_Val
: Uint
;
7831 -- Value of aggregate. The value is set in the low order bits of
7832 -- this value. For the little-endian case, the values are stored
7833 -- from low-order to high-order and for the big-endian case the
7834 -- values are stored from high-order to low-order. Note that gigi
7835 -- will take care of the conversions to left justify the value in
7836 -- the big endian case (because of left justified modular type
7837 -- processing), so we do not have to worry about that here.
7840 -- Integer literal for resulting constructed value
7843 -- Shift count from low order for next value
7846 -- Shift increment for loop
7849 -- Next expression from positional parameters of aggregate
7851 Left_Justified
: Boolean;
7852 -- Set True if we are filling the high order bits of the target
7853 -- value (i.e. the value is left justified).
7856 -- For little endian, we fill up the low order bits of the target
7857 -- value. For big endian we fill up the high order bits of the
7858 -- target value (which is a left justified modular value).
7860 Left_Justified
:= Bytes_Big_Endian
;
7862 -- Switch justification if using -gnatd8
7864 if Debug_Flag_8
then
7865 Left_Justified
:= not Left_Justified
;
7868 -- Switch justfification if reverse storage order
7870 if Reverse_Storage_Order
(Base_Type
(Typ
)) then
7871 Left_Justified
:= not Left_Justified
;
7874 if Left_Justified
then
7875 Shift
:= Csiz
* (Len
- 1);
7882 -- Loop to set the values
7885 Aggregate_Val
:= Uint_0
;
7887 Expr
:= First
(Expressions
(N
));
7888 Aggregate_Val
:= Get_Component_Val
(Expr
) * Uint_2
** Shift
;
7890 for J
in 2 .. Len
loop
7891 Shift
:= Shift
+ Incr
;
7894 Aggregate_Val
+ Get_Component_Val
(Expr
) * Uint_2
** Shift
;
7898 -- Now we can rewrite with the proper value
7900 Lit
:= Make_Integer_Literal
(Loc
, Intval
=> Aggregate_Val
);
7901 Set_Print_In_Hex
(Lit
);
7903 -- Construct the expression using this literal. Note that it is
7904 -- important to qualify the literal with its proper modular type
7905 -- since universal integer does not have the required range and
7906 -- also this is a left justified modular type, which is important
7907 -- in the big-endian case.
7910 Unchecked_Convert_To
(Typ
,
7911 Make_Qualified_Expression
(Loc
,
7913 New_Occurrence_Of
(Packed_Array_Impl_Type
(Typ
), Loc
),
7914 Expression
=> Lit
)));
7916 Analyze_And_Resolve
(N
, Typ
);
7924 end Packed_Array_Aggregate_Handled
;
7926 ----------------------------
7927 -- Has_Mutable_Components --
7928 ----------------------------
7930 function Has_Mutable_Components
(Typ
: Entity_Id
) return Boolean is
7934 Comp
:= First_Component
(Typ
);
7935 while Present
(Comp
) loop
7936 if Is_Record_Type
(Etype
(Comp
))
7937 and then Has_Discriminants
(Etype
(Comp
))
7938 and then not Is_Constrained
(Etype
(Comp
))
7943 Next_Component
(Comp
);
7947 end Has_Mutable_Components
;
7949 ------------------------------
7950 -- Initialize_Discriminants --
7951 ------------------------------
7953 procedure Initialize_Discriminants
(N
: Node_Id
; Typ
: Entity_Id
) is
7954 Loc
: constant Source_Ptr
:= Sloc
(N
);
7955 Bas
: constant Entity_Id
:= Base_Type
(Typ
);
7956 Par
: constant Entity_Id
:= Etype
(Bas
);
7957 Decl
: constant Node_Id
:= Parent
(Par
);
7961 if Is_Tagged_Type
(Bas
)
7962 and then Is_Derived_Type
(Bas
)
7963 and then Has_Discriminants
(Par
)
7964 and then Has_Discriminants
(Bas
)
7965 and then Number_Discriminants
(Bas
) /= Number_Discriminants
(Par
)
7966 and then Nkind
(Decl
) = N_Full_Type_Declaration
7967 and then Nkind
(Type_Definition
(Decl
)) = N_Record_Definition
7969 Present
(Variant_Part
(Component_List
(Type_Definition
(Decl
))))
7970 and then Nkind
(N
) /= N_Extension_Aggregate
7973 -- Call init proc to set discriminants.
7974 -- There should eventually be a special procedure for this ???
7976 Ref
:= New_Occurrence_Of
(Defining_Identifier
(N
), Loc
);
7977 Insert_Actions_After
(N
,
7978 Build_Initialization_Call
(Sloc
(N
), Ref
, Typ
));
7980 end Initialize_Discriminants
;
7987 (Obj_Type
: Entity_Id
;
7988 Typ
: Entity_Id
) return Boolean
7990 L1
, L2
, H1
, H2
: Node_Id
;
7993 -- No sliding if the type of the object is not established yet, if it is
7994 -- an unconstrained type whose actual subtype comes from the aggregate,
7995 -- or if the two types are identical.
7997 if not Is_Array_Type
(Obj_Type
) then
8000 elsif not Is_Constrained
(Obj_Type
) then
8003 elsif Typ
= Obj_Type
then
8007 -- Sliding can only occur along the first dimension
8009 Get_Index_Bounds
(First_Index
(Typ
), L1
, H1
);
8010 Get_Index_Bounds
(First_Index
(Obj_Type
), L2
, H2
);
8012 if not Is_OK_Static_Expression
(L1
) or else
8013 not Is_OK_Static_Expression
(L2
) or else
8014 not Is_OK_Static_Expression
(H1
) or else
8015 not Is_OK_Static_Expression
(H2
)
8019 return Expr_Value
(L1
) /= Expr_Value
(L2
)
8021 Expr_Value
(H1
) /= Expr_Value
(H2
);
8026 ---------------------------------
8027 -- Process_Transient_Component --
8028 ---------------------------------
8030 procedure Process_Transient_Component
8032 Comp_Typ
: Entity_Id
;
8033 Init_Expr
: Node_Id
;
8034 Fin_Call
: out Node_Id
;
8035 Hook_Clear
: out Node_Id
;
8036 Aggr
: Node_Id
:= Empty
;
8037 Stmts
: List_Id
:= No_List
)
8039 procedure Add_Item
(Item
: Node_Id
);
8040 -- Insert arbitrary node Item into the tree depending on the values of
8047 procedure Add_Item
(Item
: Node_Id
) is
8049 if Present
(Aggr
) then
8050 Insert_Action
(Aggr
, Item
);
8052 pragma Assert
(Present
(Stmts
));
8053 Append_To
(Stmts
, Item
);
8059 Hook_Assign
: Node_Id
;
8060 Hook_Decl
: Node_Id
;
8064 Res_Typ
: Entity_Id
;
8066 -- Start of processing for Process_Transient_Component
8069 -- Add the access type, which provides a reference to the function
8070 -- result. Generate:
8072 -- type Res_Typ is access all Comp_Typ;
8074 Res_Typ
:= Make_Temporary
(Loc
, 'A');
8075 Set_Ekind
(Res_Typ
, E_General_Access_Type
);
8076 Set_Directly_Designated_Type
(Res_Typ
, Comp_Typ
);
8079 (Make_Full_Type_Declaration
(Loc
,
8080 Defining_Identifier
=> Res_Typ
,
8082 Make_Access_To_Object_Definition
(Loc
,
8083 All_Present
=> True,
8084 Subtype_Indication
=> New_Occurrence_Of
(Comp_Typ
, Loc
))));
8086 -- Add the temporary which captures the result of the function call.
8089 -- Res : constant Res_Typ := Init_Expr'Reference;
8091 -- Note that this temporary is effectively a transient object because
8092 -- its lifetime is bounded by the current array or record component.
8094 Res_Id
:= Make_Temporary
(Loc
, 'R');
8095 Set_Ekind
(Res_Id
, E_Constant
);
8096 Set_Etype
(Res_Id
, Res_Typ
);
8098 -- Mark the transient object as successfully processed to avoid double
8101 Set_Is_Finalized_Transient
(Res_Id
);
8103 -- Signal the general finalization machinery that this transient object
8104 -- should not be considered for finalization actions because its cleanup
8105 -- will be performed by Process_Transient_Component_Completion.
8107 Set_Is_Ignored_Transient
(Res_Id
);
8110 Make_Object_Declaration
(Loc
,
8111 Defining_Identifier
=> Res_Id
,
8112 Constant_Present
=> True,
8113 Object_Definition
=> New_Occurrence_Of
(Res_Typ
, Loc
),
8115 Make_Reference
(Loc
, New_Copy_Tree
(Init_Expr
)));
8117 Add_Item
(Res_Decl
);
8119 -- Construct all pieces necessary to hook and finalize the transient
8122 Build_Transient_Object_Statements
8123 (Obj_Decl
=> Res_Decl
,
8124 Fin_Call
=> Fin_Call
,
8125 Hook_Assign
=> Hook_Assign
,
8126 Hook_Clear
=> Hook_Clear
,
8127 Hook_Decl
=> Hook_Decl
,
8128 Ptr_Decl
=> Ptr_Decl
);
8130 -- Add the access type which provides a reference to the transient
8131 -- result. Generate:
8133 -- type Ptr_Typ is access all Comp_Typ;
8135 Add_Item
(Ptr_Decl
);
8137 -- Add the temporary which acts as a hook to the transient result.
8140 -- Hook : Ptr_Typ := null;
8142 Add_Item
(Hook_Decl
);
8144 -- Attach the transient result to the hook. Generate:
8146 -- Hook := Ptr_Typ (Res);
8148 Add_Item
(Hook_Assign
);
8150 -- The original initialization expression now references the value of
8151 -- the temporary function result. Generate:
8156 Make_Explicit_Dereference
(Loc
,
8157 Prefix
=> New_Occurrence_Of
(Res_Id
, Loc
)));
8158 end Process_Transient_Component
;
8160 --------------------------------------------
8161 -- Process_Transient_Component_Completion --
8162 --------------------------------------------
8164 procedure Process_Transient_Component_Completion
8168 Hook_Clear
: Node_Id
;
8171 Exceptions_OK
: constant Boolean :=
8172 not Restriction_Active
(No_Exception_Propagation
);
8175 pragma Assert
(Present
(Hook_Clear
));
8177 -- Generate the following code if exception propagation is allowed:
8180 -- Abort : constant Boolean := Triggered_By_Abort;
8182 -- Abort : constant Boolean := False; -- no abort
8184 -- E : Exception_Occurrence;
8185 -- Raised : Boolean := False;
8192 -- [Deep_]Finalize (Res.all);
8196 -- if not Raised then
8198 -- Save_Occurrence (E,
8199 -- Get_Curent_Excep.all.all);
8205 -- if Raised and then not Abort then
8206 -- Raise_From_Controlled_Operation (E);
8210 if Exceptions_OK
then
8211 Abort_And_Exception
: declare
8212 Blk_Decls
: constant List_Id
:= New_List
;
8213 Blk_Stmts
: constant List_Id
:= New_List
;
8214 Fin_Stmts
: constant List_Id
:= New_List
;
8216 Fin_Data
: Finalization_Exception_Data
;
8219 -- Create the declarations of the two flags and the exception
8222 Build_Object_Declarations
(Fin_Data
, Blk_Decls
, Loc
);
8227 if Abort_Allowed
then
8228 Append_To
(Blk_Stmts
,
8229 Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
8232 -- Wrap the hook clear and the finalization call in order to trap
8233 -- a potential exception.
8235 Append_To
(Fin_Stmts
, Hook_Clear
);
8237 if Present
(Fin_Call
) then
8238 Append_To
(Fin_Stmts
, Fin_Call
);
8241 Append_To
(Blk_Stmts
,
8242 Make_Block_Statement
(Loc
,
8243 Handled_Statement_Sequence
=>
8244 Make_Handled_Sequence_Of_Statements
(Loc
,
8245 Statements
=> Fin_Stmts
,
8246 Exception_Handlers
=> New_List
(
8247 Build_Exception_Handler
(Fin_Data
)))));
8252 if Abort_Allowed
then
8253 Append_To
(Blk_Stmts
,
8254 Build_Runtime_Call
(Loc
, RE_Abort_Undefer
));
8257 -- Reraise the potential exception with a proper "upgrade" to
8258 -- Program_Error if needed.
8260 Append_To
(Blk_Stmts
, Build_Raise_Statement
(Fin_Data
));
8262 -- Wrap everything in a block
8265 Make_Block_Statement
(Loc
,
8266 Declarations
=> Blk_Decls
,
8267 Handled_Statement_Sequence
=>
8268 Make_Handled_Sequence_Of_Statements
(Loc
,
8269 Statements
=> Blk_Stmts
)));
8270 end Abort_And_Exception
;
8272 -- Generate the following code if exception propagation is not allowed
8273 -- and aborts are allowed:
8278 -- [Deep_]Finalize (Res.all);
8280 -- Abort_Undefer_Direct;
8283 elsif Abort_Allowed
then
8284 Abort_Only
: declare
8285 Blk_Stmts
: constant List_Id
:= New_List
;
8288 Append_To
(Blk_Stmts
, Build_Runtime_Call
(Loc
, RE_Abort_Defer
));
8289 Append_To
(Blk_Stmts
, Hook_Clear
);
8291 if Present
(Fin_Call
) then
8292 Append_To
(Blk_Stmts
, Fin_Call
);
8296 Build_Abort_Undefer_Block
(Loc
,
8301 -- Otherwise generate:
8304 -- [Deep_]Finalize (Res.all);
8307 Append_To
(Stmts
, Hook_Clear
);
8309 if Present
(Fin_Call
) then
8310 Append_To
(Stmts
, Fin_Call
);
8313 end Process_Transient_Component_Completion
;
8315 ---------------------
8316 -- Sort_Case_Table --
8317 ---------------------
8319 procedure Sort_Case_Table
(Case_Table
: in out Case_Table_Type
) is
8320 L
: constant Int
:= Case_Table
'First;
8321 U
: constant Int
:= Case_Table
'Last;
8329 T
:= Case_Table
(K
+ 1);
8333 and then Expr_Value
(Case_Table
(J
- 1).Choice_Lo
) >
8334 Expr_Value
(T
.Choice_Lo
)
8336 Case_Table
(J
) := Case_Table
(J
- 1);
8340 Case_Table
(J
) := T
;
8343 end Sort_Case_Table
;
8345 ----------------------------
8346 -- Static_Array_Aggregate --
8347 ----------------------------
8349 function Static_Array_Aggregate
(N
: Node_Id
) return Boolean is
8350 Bounds
: constant Node_Id
:= Aggregate_Bounds
(N
);
8352 Typ
: constant Entity_Id
:= Etype
(N
);
8353 Comp_Type
: constant Entity_Id
:= Component_Type
(Typ
);
8360 if Is_Tagged_Type
(Typ
)
8361 or else Is_Controlled
(Typ
)
8362 or else Is_Packed
(Typ
)
8368 and then Nkind
(Bounds
) = N_Range
8369 and then Nkind
(Low_Bound
(Bounds
)) = N_Integer_Literal
8370 and then Nkind
(High_Bound
(Bounds
)) = N_Integer_Literal
8372 Lo
:= Low_Bound
(Bounds
);
8373 Hi
:= High_Bound
(Bounds
);
8375 if No
(Component_Associations
(N
)) then
8377 -- Verify that all components are static integers
8379 Expr
:= First
(Expressions
(N
));
8380 while Present
(Expr
) loop
8381 if Nkind
(Expr
) /= N_Integer_Literal
then
8391 -- We allow only a single named association, either a static
8392 -- range or an others_clause, with a static expression.
8394 Expr
:= First
(Component_Associations
(N
));
8396 if Present
(Expressions
(N
)) then
8399 elsif Present
(Next
(Expr
)) then
8402 elsif Present
(Next
(First
(Choice_List
(Expr
)))) then
8406 -- The aggregate is static if all components are literals,
8407 -- or else all its components are static aggregates for the
8408 -- component type. We also limit the size of a static aggregate
8409 -- to prevent runaway static expressions.
8411 if Is_Array_Type
(Comp_Type
)
8412 or else Is_Record_Type
(Comp_Type
)
8414 if Nkind
(Expression
(Expr
)) /= N_Aggregate
8416 not Compile_Time_Known_Aggregate
(Expression
(Expr
))
8421 elsif Nkind
(Expression
(Expr
)) /= N_Integer_Literal
then
8425 if not Aggr_Size_OK
(N
, Typ
) then
8429 -- Create a positional aggregate with the right number of
8430 -- copies of the expression.
8432 Agg
:= Make_Aggregate
(Sloc
(N
), New_List
, No_List
);
8434 for I
in UI_To_Int
(Intval
(Lo
)) .. UI_To_Int
(Intval
(Hi
))
8436 Append_To
(Expressions
(Agg
), New_Copy
(Expression
(Expr
)));
8438 -- The copied expression must be analyzed and resolved.
8439 -- Besides setting the type, this ensures that static
8440 -- expressions are appropriately marked as such.
8443 (Last
(Expressions
(Agg
)), Component_Type
(Typ
));
8446 Set_Aggregate_Bounds
(Agg
, Bounds
);
8447 Set_Etype
(Agg
, Typ
);
8450 Set_Compile_Time_Known_Aggregate
(N
);
8459 end Static_Array_Aggregate
;
8461 ----------------------------------
8462 -- Two_Dim_Packed_Array_Handled --
8463 ----------------------------------
8465 function Two_Dim_Packed_Array_Handled
(N
: Node_Id
) return Boolean is
8466 Loc
: constant Source_Ptr
:= Sloc
(N
);
8467 Typ
: constant Entity_Id
:= Etype
(N
);
8468 Ctyp
: constant Entity_Id
:= Component_Type
(Typ
);
8469 Comp_Size
: constant Int
:= UI_To_Int
(Component_Size
(Typ
));
8470 Packed_Array
: constant Entity_Id
:=
8471 Packed_Array_Impl_Type
(Base_Type
(Typ
));
8474 -- Expression in original aggregate
8477 -- One-dimensional subaggregate
8481 -- For now, only deal with cases where an integral number of elements
8482 -- fit in a single byte. This includes the most common boolean case.
8484 if not (Comp_Size
= 1 or else
8485 Comp_Size
= 2 or else
8491 Convert_To_Positional
8492 (N
, Max_Others_Replicate
=> 64, Handle_Bit_Packed
=> True);
8494 -- Verify that all components are static
8496 if Nkind
(N
) = N_Aggregate
8497 and then Compile_Time_Known_Aggregate
(N
)
8501 -- The aggregate may have been reanalyzed and converted already
8503 elsif Nkind
(N
) /= N_Aggregate
then
8506 -- If component associations remain, the aggregate is not static
8508 elsif Present
(Component_Associations
(N
)) then
8512 One_Dim
:= First
(Expressions
(N
));
8513 while Present
(One_Dim
) loop
8514 if Present
(Component_Associations
(One_Dim
)) then
8518 One_Comp
:= First
(Expressions
(One_Dim
));
8519 while Present
(One_Comp
) loop
8520 if not Is_OK_Static_Expression
(One_Comp
) then
8531 -- Two-dimensional aggregate is now fully positional so pack one
8532 -- dimension to create a static one-dimensional array, and rewrite
8533 -- as an unchecked conversion to the original type.
8536 Byte_Size
: constant Int
:= UI_To_Int
(Component_Size
(Packed_Array
));
8537 -- The packed array type is a byte array
8540 -- Number of components accumulated in current byte
8543 -- Assembled list of packed values for equivalent aggregate
8546 -- Integer value of component
8549 -- Step size for packing
8552 -- Endian-dependent start position for packing
8555 -- Current insertion position
8558 -- Component of packed array being assembled
8565 -- Account for endianness. See corresponding comment in
8566 -- Packed_Array_Aggregate_Handled concerning the following.
8570 xor Reverse_Storage_Order
(Base_Type
(Typ
))
8572 Init_Shift
:= Byte_Size
- Comp_Size
;
8579 -- Iterate over each subaggregate
8581 Shift
:= Init_Shift
;
8582 One_Dim
:= First
(Expressions
(N
));
8583 while Present
(One_Dim
) loop
8584 One_Comp
:= First
(Expressions
(One_Dim
));
8585 while Present
(One_Comp
) loop
8586 if Packed_Num
= Byte_Size
/ Comp_Size
then
8588 -- Byte is complete, add to list of expressions
8590 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
8592 Shift
:= Init_Shift
;
8596 Comp_Val
:= Expr_Rep_Value
(One_Comp
);
8598 -- Adjust for bias, and strip proper number of bits
8600 if Has_Biased_Representation
(Ctyp
) then
8601 Comp_Val
:= Comp_Val
- Expr_Value
(Type_Low_Bound
(Ctyp
));
8604 Comp_Val
:= Comp_Val
mod Uint_2
** Comp_Size
;
8605 Val
:= UI_To_Int
(Val
+ Comp_Val
* Uint_2
** Shift
);
8606 Shift
:= Shift
+ Incr
;
8607 One_Comp
:= Next
(One_Comp
);
8608 Packed_Num
:= Packed_Num
+ 1;
8612 One_Dim
:= Next
(One_Dim
);
8615 if Packed_Num
> 0 then
8617 -- Add final incomplete byte if present
8619 Append
(Make_Integer_Literal
(Sloc
(One_Dim
), Val
), Comps
);
8623 Unchecked_Convert_To
(Typ
,
8624 Make_Qualified_Expression
(Loc
,
8625 Subtype_Mark
=> New_Occurrence_Of
(Packed_Array
, Loc
),
8626 Expression
=> Make_Aggregate
(Loc
, Expressions
=> Comps
))));
8627 Analyze_And_Resolve
(N
);
8630 end Two_Dim_Packed_Array_Handled
;