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 Contracts
; use Contracts
;
29 with Debug
; use Debug
;
30 with Einfo
; use Einfo
;
31 with Errout
; use Errout
;
32 with Elists
; use Elists
;
33 with Expander
; use Expander
;
34 with Exp_Aggr
; use Exp_Aggr
;
35 with Exp_Atag
; use Exp_Atag
;
36 with Exp_Ch2
; use Exp_Ch2
;
37 with Exp_Ch3
; use Exp_Ch3
;
38 with Exp_Ch7
; use Exp_Ch7
;
39 with Exp_Ch9
; use Exp_Ch9
;
40 with Exp_Dbug
; use Exp_Dbug
;
41 with Exp_Disp
; use Exp_Disp
;
42 with Exp_Dist
; use Exp_Dist
;
43 with Exp_Intr
; use Exp_Intr
;
44 with Exp_Pakd
; use Exp_Pakd
;
45 with Exp_Tss
; use Exp_Tss
;
46 with Exp_Util
; use Exp_Util
;
47 with Freeze
; use Freeze
;
48 with Inline
; use Inline
;
49 with Itypes
; use Itypes
;
51 with Namet
; use Namet
;
52 with Nlists
; use Nlists
;
53 with Nmake
; use Nmake
;
55 with Restrict
; use Restrict
;
56 with Rident
; use Rident
;
57 with Rtsfind
; use Rtsfind
;
59 with Sem_Aux
; use Sem_Aux
;
60 with Sem_Ch6
; use Sem_Ch6
;
61 with Sem_Ch8
; use Sem_Ch8
;
62 with Sem_Ch12
; use Sem_Ch12
;
63 with Sem_Ch13
; use Sem_Ch13
;
64 with Sem_Dim
; use Sem_Dim
;
65 with Sem_Disp
; use Sem_Disp
;
66 with Sem_Dist
; use Sem_Dist
;
67 with Sem_Eval
; use Sem_Eval
;
68 with Sem_Mech
; use Sem_Mech
;
69 with Sem_Res
; use Sem_Res
;
70 with Sem_SCIL
; use Sem_SCIL
;
71 with Sem_Util
; use Sem_Util
;
72 with Sinfo
; use Sinfo
;
73 with Snames
; use Snames
;
74 with Stand
; use Stand
;
75 with Tbuild
; use Tbuild
;
76 with Uintp
; use Uintp
;
77 with Validsw
; use Validsw
;
79 package body Exp_Ch6
is
81 -----------------------
82 -- Local Subprograms --
83 -----------------------
85 procedure Add_Access_Actual_To_Build_In_Place_Call
86 (Function_Call
: Node_Id
;
87 Function_Id
: Entity_Id
;
88 Return_Object
: Node_Id
;
89 Is_Access
: Boolean := False);
90 -- Ada 2005 (AI-318-02): Apply the Unrestricted_Access attribute to the
91 -- object name given by Return_Object and add the attribute to the end of
92 -- the actual parameter list associated with the build-in-place function
93 -- call denoted by Function_Call. However, if Is_Access is True, then
94 -- Return_Object is already an access expression, in which case it's passed
95 -- along directly to the build-in-place function. Finally, if Return_Object
96 -- is empty, then pass a null literal as the actual.
98 procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
99 (Function_Call
: Node_Id
;
100 Function_Id
: Entity_Id
;
101 Alloc_Form
: BIP_Allocation_Form
:= Unspecified
;
102 Alloc_Form_Exp
: Node_Id
:= Empty
;
103 Pool_Actual
: Node_Id
:= Make_Null
(No_Location
));
104 -- Ada 2005 (AI-318-02): Add the actuals needed for a build-in-place
105 -- function call that returns a caller-unknown-size result (BIP_Alloc_Form
106 -- and BIP_Storage_Pool). If Alloc_Form_Exp is present, then use it,
107 -- otherwise pass a literal corresponding to the Alloc_Form parameter
108 -- (which must not be Unspecified in that case). Pool_Actual is the
109 -- parameter to pass to BIP_Storage_Pool.
111 procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
112 (Func_Call
: Node_Id
;
114 Ptr_Typ
: Entity_Id
:= Empty
;
115 Master_Exp
: Node_Id
:= Empty
);
116 -- Ada 2005 (AI-318-02): If the result type of a build-in-place call needs
117 -- finalization actions, add an actual parameter which is a pointer to the
118 -- finalization master of the caller. If Master_Exp is not Empty, then that
119 -- will be passed as the actual. Otherwise, if Ptr_Typ is left Empty, this
120 -- will result in an automatic "null" value for the actual.
122 procedure Add_Task_Actuals_To_Build_In_Place_Call
123 (Function_Call
: Node_Id
;
124 Function_Id
: Entity_Id
;
125 Master_Actual
: Node_Id
;
126 Chain
: Node_Id
:= Empty
);
127 -- Ada 2005 (AI-318-02): For a build-in-place call, if the result type
128 -- contains tasks, add two actual parameters: the master, and a pointer to
129 -- the caller's activation chain. Master_Actual is the actual parameter
130 -- expression to pass for the master. In most cases, this is the current
131 -- master (_master). The two exceptions are: If the function call is the
132 -- initialization expression for an allocator, we pass the master of the
133 -- access type. If the function call is the initialization expression for a
134 -- return object, we pass along the master passed in by the caller. In most
135 -- contexts, the activation chain to pass is the local one, which is
136 -- indicated by No (Chain). However, in an allocator, the caller passes in
137 -- the activation Chain. Note: Master_Actual can be Empty, but only if
138 -- there are no tasks.
140 function Caller_Known_Size
141 (Func_Call
: Node_Id
;
142 Result_Subt
: Entity_Id
) return Boolean;
143 -- True if result subtype is definite, or has a size that does not require
144 -- secondary stack usage (i.e. no variant part or components whose type
145 -- depends on discriminants). In particular, untagged types with only
146 -- access discriminants do not require secondary stack use. Note we must
147 -- always use the secondary stack for dispatching-on-result calls.
149 procedure Check_Overriding_Operation
(Subp
: Entity_Id
);
150 -- Subp is a dispatching operation. Check whether it may override an
151 -- inherited private operation, in which case its DT entry is that of
152 -- the hidden operation, not the one it may have received earlier.
153 -- This must be done before emitting the code to set the corresponding
154 -- DT to the address of the subprogram. The actual placement of Subp in
155 -- the proper place in the list of primitive operations is done in
156 -- Declare_Inherited_Private_Subprograms, which also has to deal with
157 -- implicit operations. This duplication is unavoidable for now???
159 procedure Detect_Infinite_Recursion
(N
: Node_Id
; Spec
: Entity_Id
);
160 -- This procedure is called only if the subprogram body N, whose spec
161 -- has the given entity Spec, contains a parameterless recursive call.
162 -- It attempts to generate runtime code to detect if this a case of
163 -- infinite recursion.
165 -- The body is scanned to determine dependencies. If the only external
166 -- dependencies are on a small set of scalar variables, then the values
167 -- of these variables are captured on entry to the subprogram, and if
168 -- the values are not changed for the call, we know immediately that
169 -- we have an infinite recursion.
171 procedure Expand_Actuals
174 Post_Call
: out List_Id
);
175 -- Return a list of actions to take place after the call in Post_Call. The
176 -- call will later be rewritten as an Expression_With_Actions, with the
177 -- Post_Call actions inserted, and the call inside.
179 -- For each actual of an in-out or out parameter which is a numeric (view)
180 -- conversion of the form T (A), where A denotes a variable, we insert the
183 -- Temp : T[ := T (A)];
185 -- prior to the call. Then we replace the actual with a reference to Temp,
186 -- and append the assignment:
188 -- A := TypeA (Temp);
190 -- after the call. Here TypeA is the actual type of variable A. For out
191 -- parameters, the initial declaration has no expression. If A is not an
192 -- entity name, we generate instead:
194 -- Var : TypeA renames A;
195 -- Temp : T := Var; -- omitting expression for out parameter.
197 -- Var := TypeA (Temp);
199 -- For other in-out parameters, we emit the required constraint checks
200 -- before and/or after the call.
202 -- For all parameter modes, actuals that denote components and slices of
203 -- packed arrays are expanded into suitable temporaries.
205 -- For non-scalar objects that are possibly unaligned, add call by copy
206 -- code (copy in for IN and IN OUT, copy out for OUT and IN OUT).
208 -- For OUT and IN OUT parameters, add predicate checks after the call
209 -- based on the predicates of the actual type.
211 procedure Expand_Call_Helper
(N
: Node_Id
; Post_Call
: out List_Id
);
212 -- Does the main work of Expand_Call. Post_Call is as for Expand_Actuals.
214 procedure Expand_Ctrl_Function_Call
(N
: Node_Id
);
215 -- N is a function call which returns a controlled object. Transform the
216 -- call into a temporary which retrieves the returned object from the
217 -- secondary stack using 'reference.
219 procedure Expand_Non_Function_Return
(N
: Node_Id
);
220 -- Expand a simple return statement found in a procedure body, entry body,
221 -- accept statement, or an extended return statement. Note that all non-
222 -- function returns are simple return statements.
224 function Expand_Protected_Object_Reference
226 Scop
: Entity_Id
) return Node_Id
;
228 procedure Expand_Protected_Subprogram_Call
232 -- A call to a protected subprogram within the protected object may appear
233 -- as a regular call. The list of actuals must be expanded to contain a
234 -- reference to the object itself, and the call becomes a call to the
235 -- corresponding protected subprogram.
237 procedure Expand_Simple_Function_Return
(N
: Node_Id
);
238 -- Expand simple return from function. In the case where we are returning
239 -- from a function body this is called by Expand_N_Simple_Return_Statement.
241 function Has_Unconstrained_Access_Discriminants
242 (Subtyp
: Entity_Id
) return Boolean;
243 -- Returns True if the given subtype is unconstrained and has one or more
244 -- access discriminants.
246 procedure Insert_Post_Call_Actions
(N
: Node_Id
; Post_Call
: List_Id
);
247 -- Insert the Post_Call list previously produced by routine Expand_Actuals
248 -- or Expand_Call_Helper into the tree.
250 procedure Replace_Renaming_Declaration_Id
252 Orig_Decl
: Node_Id
);
253 -- Replace the internal identifier of the new renaming declaration New_Decl
254 -- with the identifier of its original declaration Orig_Decl exchanging the
255 -- entities containing their defining identifiers to ensure the correct
256 -- replacement of the object declaration by the object renaming declaration
257 -- to avoid homograph conflicts (since the object declaration's defining
258 -- identifier was already entered in the current scope). The Next_Entity
259 -- links of the two entities are also swapped since the entities are part
260 -- of the return scope's entity list and the list structure would otherwise
261 -- be corrupted. The homonym chain is preserved as well.
263 procedure Rewrite_Function_Call_For_C
(N
: Node_Id
);
264 -- When generating C code, replace a call to a function that returns an
265 -- array into the generated procedure with an additional out parameter.
267 procedure Set_Enclosing_Sec_Stack_Return
(N
: Node_Id
);
268 -- N is a return statement for a function that returns its result on the
269 -- secondary stack. This sets the Sec_Stack_Needed_For_Return flag on the
270 -- function and all blocks and loops that the return statement is jumping
271 -- out of. This ensures that the secondary stack is not released; otherwise
272 -- the function result would be reclaimed before returning to the caller.
274 ----------------------------------------------
275 -- Add_Access_Actual_To_Build_In_Place_Call --
276 ----------------------------------------------
278 procedure Add_Access_Actual_To_Build_In_Place_Call
279 (Function_Call
: Node_Id
;
280 Function_Id
: Entity_Id
;
281 Return_Object
: Node_Id
;
282 Is_Access
: Boolean := False)
284 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
285 Obj_Address
: Node_Id
;
286 Obj_Acc_Formal
: Entity_Id
;
289 -- Locate the implicit access parameter in the called function
291 Obj_Acc_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Object_Access
);
293 -- If no return object is provided, then pass null
295 if not Present
(Return_Object
) then
296 Obj_Address
:= Make_Null
(Loc
);
297 Set_Parent
(Obj_Address
, Function_Call
);
299 -- If Return_Object is already an expression of an access type, then use
300 -- it directly, since it must be an access value denoting the return
301 -- object, and couldn't possibly be the return object itself.
304 Obj_Address
:= Return_Object
;
305 Set_Parent
(Obj_Address
, Function_Call
);
307 -- Apply Unrestricted_Access to caller's return object
311 Make_Attribute_Reference
(Loc
,
312 Prefix
=> Return_Object
,
313 Attribute_Name
=> Name_Unrestricted_Access
);
315 Set_Parent
(Return_Object
, Obj_Address
);
316 Set_Parent
(Obj_Address
, Function_Call
);
319 Analyze_And_Resolve
(Obj_Address
, Etype
(Obj_Acc_Formal
));
321 -- Build the parameter association for the new actual and add it to the
322 -- end of the function's actuals.
324 Add_Extra_Actual_To_Call
(Function_Call
, Obj_Acc_Formal
, Obj_Address
);
325 end Add_Access_Actual_To_Build_In_Place_Call
;
327 ------------------------------------------------------
328 -- Add_Unconstrained_Actuals_To_Build_In_Place_Call --
329 ------------------------------------------------------
331 procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
332 (Function_Call
: Node_Id
;
333 Function_Id
: Entity_Id
;
334 Alloc_Form
: BIP_Allocation_Form
:= Unspecified
;
335 Alloc_Form_Exp
: Node_Id
:= Empty
;
336 Pool_Actual
: Node_Id
:= Make_Null
(No_Location
))
338 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
339 Alloc_Form_Actual
: Node_Id
;
340 Alloc_Form_Formal
: Node_Id
;
341 Pool_Formal
: Node_Id
;
344 -- The allocation form generally doesn't need to be passed in the case
345 -- of a constrained result subtype, since normally the caller performs
346 -- the allocation in that case. However this formal is still needed in
347 -- the case where the function has a tagged result, because generally
348 -- such functions can be called in a dispatching context and such calls
349 -- must be handled like calls to class-wide functions.
351 if Is_Constrained
(Underlying_Type
(Etype
(Function_Id
)))
352 and then not Is_Tagged_Type
(Underlying_Type
(Etype
(Function_Id
)))
357 -- Locate the implicit allocation form parameter in the called function.
358 -- Maybe it would be better for each implicit formal of a build-in-place
359 -- function to have a flag or a Uint attribute to identify it. ???
361 Alloc_Form_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Alloc_Form
);
363 if Present
(Alloc_Form_Exp
) then
364 pragma Assert
(Alloc_Form
= Unspecified
);
366 Alloc_Form_Actual
:= Alloc_Form_Exp
;
369 pragma Assert
(Alloc_Form
/= Unspecified
);
372 Make_Integer_Literal
(Loc
,
373 Intval
=> UI_From_Int
(BIP_Allocation_Form
'Pos (Alloc_Form
)));
376 Analyze_And_Resolve
(Alloc_Form_Actual
, Etype
(Alloc_Form_Formal
));
378 -- Build the parameter association for the new actual and add it to the
379 -- end of the function's actuals.
381 Add_Extra_Actual_To_Call
382 (Function_Call
, Alloc_Form_Formal
, Alloc_Form_Actual
);
384 -- Pass the Storage_Pool parameter. This parameter is omitted on
385 -- ZFP as those targets do not support pools.
387 if RTE_Available
(RE_Root_Storage_Pool_Ptr
) then
388 Pool_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Storage_Pool
);
389 Analyze_And_Resolve
(Pool_Actual
, Etype
(Pool_Formal
));
390 Add_Extra_Actual_To_Call
391 (Function_Call
, Pool_Formal
, Pool_Actual
);
393 end Add_Unconstrained_Actuals_To_Build_In_Place_Call
;
395 -----------------------------------------------------------
396 -- Add_Finalization_Master_Actual_To_Build_In_Place_Call --
397 -----------------------------------------------------------
399 procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
400 (Func_Call
: Node_Id
;
402 Ptr_Typ
: Entity_Id
:= Empty
;
403 Master_Exp
: Node_Id
:= Empty
)
406 if not Needs_BIP_Finalization_Master
(Func_Id
) then
411 Formal
: constant Entity_Id
:=
412 Build_In_Place_Formal
(Func_Id
, BIP_Finalization_Master
);
413 Loc
: constant Source_Ptr
:= Sloc
(Func_Call
);
416 Desig_Typ
: Entity_Id
;
419 -- If there is a finalization master actual, such as the implicit
420 -- finalization master of an enclosing build-in-place function,
421 -- then this must be added as an extra actual of the call.
423 if Present
(Master_Exp
) then
424 Actual
:= Master_Exp
;
426 -- Case where the context does not require an actual master
428 elsif No
(Ptr_Typ
) then
429 Actual
:= Make_Null
(Loc
);
432 Desig_Typ
:= Directly_Designated_Type
(Ptr_Typ
);
434 -- Check for a library-level access type whose designated type has
435 -- suppressed finalization or the access type is subject to pragma
436 -- No_Heap_Finalization. Such an access type lacks a master. Pass
437 -- a null actual to callee in order to signal a missing master.
439 if Is_Library_Level_Entity
(Ptr_Typ
)
440 and then (Finalize_Storage_Only
(Desig_Typ
)
441 or else No_Heap_Finalization
(Ptr_Typ
))
443 Actual
:= Make_Null
(Loc
);
445 -- Types in need of finalization actions
447 elsif Needs_Finalization
(Desig_Typ
) then
449 -- The general mechanism of creating finalization masters for
450 -- anonymous access types is disabled by default, otherwise
451 -- finalization masters will pop all over the place. Such types
452 -- use context-specific masters.
454 if Ekind
(Ptr_Typ
) = E_Anonymous_Access_Type
455 and then No
(Finalization_Master
(Ptr_Typ
))
457 Build_Anonymous_Master
(Ptr_Typ
);
460 -- Access-to-controlled types should always have a master
462 pragma Assert
(Present
(Finalization_Master
(Ptr_Typ
)));
465 Make_Attribute_Reference
(Loc
,
467 New_Occurrence_Of
(Finalization_Master
(Ptr_Typ
), Loc
),
468 Attribute_Name
=> Name_Unrestricted_Access
);
473 Actual
:= Make_Null
(Loc
);
477 Analyze_And_Resolve
(Actual
, Etype
(Formal
));
479 -- Build the parameter association for the new actual and add it to
480 -- the end of the function's actuals.
482 Add_Extra_Actual_To_Call
(Func_Call
, Formal
, Actual
);
484 end Add_Finalization_Master_Actual_To_Build_In_Place_Call
;
486 ------------------------------
487 -- Add_Extra_Actual_To_Call --
488 ------------------------------
490 procedure Add_Extra_Actual_To_Call
491 (Subprogram_Call
: Node_Id
;
492 Extra_Formal
: Entity_Id
;
493 Extra_Actual
: Node_Id
)
495 Loc
: constant Source_Ptr
:= Sloc
(Subprogram_Call
);
496 Param_Assoc
: Node_Id
;
500 Make_Parameter_Association
(Loc
,
501 Selector_Name
=> New_Occurrence_Of
(Extra_Formal
, Loc
),
502 Explicit_Actual_Parameter
=> Extra_Actual
);
504 Set_Parent
(Param_Assoc
, Subprogram_Call
);
505 Set_Parent
(Extra_Actual
, Param_Assoc
);
507 if Present
(Parameter_Associations
(Subprogram_Call
)) then
508 if Nkind
(Last
(Parameter_Associations
(Subprogram_Call
))) =
509 N_Parameter_Association
512 -- Find last named actual, and append
517 L
:= First_Actual
(Subprogram_Call
);
518 while Present
(L
) loop
519 if No
(Next_Actual
(L
)) then
520 Set_Next_Named_Actual
(Parent
(L
), Extra_Actual
);
528 Set_First_Named_Actual
(Subprogram_Call
, Extra_Actual
);
531 Append
(Param_Assoc
, To
=> Parameter_Associations
(Subprogram_Call
));
534 Set_Parameter_Associations
(Subprogram_Call
, New_List
(Param_Assoc
));
535 Set_First_Named_Actual
(Subprogram_Call
, Extra_Actual
);
537 end Add_Extra_Actual_To_Call
;
539 ---------------------------------------------
540 -- Add_Task_Actuals_To_Build_In_Place_Call --
541 ---------------------------------------------
543 procedure Add_Task_Actuals_To_Build_In_Place_Call
544 (Function_Call
: Node_Id
;
545 Function_Id
: Entity_Id
;
546 Master_Actual
: Node_Id
;
547 Chain
: Node_Id
:= Empty
)
549 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
550 Result_Subt
: constant Entity_Id
:=
551 Available_View
(Etype
(Function_Id
));
553 Chain_Actual
: Node_Id
;
554 Chain_Formal
: Node_Id
;
555 Master_Formal
: Node_Id
;
558 -- No such extra parameters are needed if there are no tasks
560 if not Has_Task
(Result_Subt
) then
564 Actual
:= Master_Actual
;
566 -- Use a dummy _master actual in case of No_Task_Hierarchy
568 if Restriction_Active
(No_Task_Hierarchy
) then
569 Actual
:= New_Occurrence_Of
(RTE
(RE_Library_Task_Level
), Loc
);
571 -- In the case where we use the master associated with an access type,
572 -- the actual is an entity and requires an explicit reference.
574 elsif Nkind
(Actual
) = N_Defining_Identifier
then
575 Actual
:= New_Occurrence_Of
(Actual
, Loc
);
578 -- Locate the implicit master parameter in the called function
580 Master_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Task_Master
);
581 Analyze_And_Resolve
(Actual
, Etype
(Master_Formal
));
583 -- Build the parameter association for the new actual and add it to the
584 -- end of the function's actuals.
586 Add_Extra_Actual_To_Call
(Function_Call
, Master_Formal
, Actual
);
588 -- Locate the implicit activation chain parameter in the called function
591 Build_In_Place_Formal
(Function_Id
, BIP_Activation_Chain
);
593 -- Create the actual which is a pointer to the current activation chain
597 Make_Attribute_Reference
(Loc
,
598 Prefix
=> Make_Identifier
(Loc
, Name_uChain
),
599 Attribute_Name
=> Name_Unrestricted_Access
);
601 -- Allocator case; make a reference to the Chain passed in by the caller
605 Make_Attribute_Reference
(Loc
,
606 Prefix
=> New_Occurrence_Of
(Chain
, Loc
),
607 Attribute_Name
=> Name_Unrestricted_Access
);
610 Analyze_And_Resolve
(Chain_Actual
, Etype
(Chain_Formal
));
612 -- Build the parameter association for the new actual and add it to the
613 -- end of the function's actuals.
615 Add_Extra_Actual_To_Call
(Function_Call
, Chain_Formal
, Chain_Actual
);
616 end Add_Task_Actuals_To_Build_In_Place_Call
;
618 -----------------------
619 -- BIP_Formal_Suffix --
620 -----------------------
622 function BIP_Formal_Suffix
(Kind
: BIP_Formal_Kind
) return String is
625 when BIP_Alloc_Form
=>
628 when BIP_Storage_Pool
=>
629 return "BIPstoragepool";
631 when BIP_Finalization_Master
=>
632 return "BIPfinalizationmaster";
634 when BIP_Task_Master
=>
635 return "BIPtaskmaster";
637 when BIP_Activation_Chain
=>
638 return "BIPactivationchain";
640 when BIP_Object_Access
=>
643 end BIP_Formal_Suffix
;
645 ---------------------------
646 -- Build_In_Place_Formal --
647 ---------------------------
649 function Build_In_Place_Formal
651 Kind
: BIP_Formal_Kind
) return Entity_Id
653 Formal_Suffix
: constant String := BIP_Formal_Suffix
(Kind
);
654 Extra_Formal
: Entity_Id
:= Extra_Formals
(Func
);
657 -- Maybe it would be better for each implicit formal of a build-in-place
658 -- function to have a flag or a Uint attribute to identify it. ???
660 -- The return type in the function declaration may have been a limited
661 -- view, and the extra formals for the function were not generated at
662 -- that point. At the point of call the full view must be available and
663 -- the extra formals can be created.
665 if No
(Extra_Formal
) then
666 Create_Extra_Formals
(Func
);
667 Extra_Formal
:= Extra_Formals
(Func
);
670 -- We search for a formal with a matching suffix. We can't search
671 -- for the full name, because of the code at the end of Sem_Ch6.-
672 -- Create_Extra_Formals, which copies the Extra_Formals over to
673 -- the Alias of an instance, which will cause the formals to have
674 -- "incorrect" names.
677 pragma Assert
(Present
(Extra_Formal
));
679 Name
: constant String := Get_Name_String
(Chars
(Extra_Formal
));
681 exit when Name
'Length >= Formal_Suffix
'Length
682 and then Formal_Suffix
=
683 Name
(Name
'Last - Formal_Suffix
'Length + 1 .. Name
'Last);
686 Next_Formal_With_Extras
(Extra_Formal
);
690 end Build_In_Place_Formal
;
692 -------------------------------
693 -- Build_Procedure_Body_Form --
694 -------------------------------
696 function Build_Procedure_Body_Form
697 (Func_Id
: Entity_Id
;
698 Func_Body
: Node_Id
) return Node_Id
700 Loc
: constant Source_Ptr
:= Sloc
(Func_Body
);
702 Proc_Decl
: constant Node_Id
:=
703 Next
(Unit_Declaration_Node
(Func_Id
));
704 -- It is assumed that the next node following the declaration of the
705 -- corresponding subprogram spec is the declaration of the procedure
708 Proc_Id
: constant Entity_Id
:= Defining_Entity
(Proc_Decl
);
710 procedure Replace_Returns
(Param_Id
: Entity_Id
; Stmts
: List_Id
);
711 -- Replace each return statement found in the list Stmts with an
712 -- assignment of the return expression to parameter Param_Id.
714 ---------------------
715 -- Replace_Returns --
716 ---------------------
718 procedure Replace_Returns
(Param_Id
: Entity_Id
; Stmts
: List_Id
) is
722 Stmt
:= First
(Stmts
);
723 while Present
(Stmt
) loop
724 if Nkind
(Stmt
) = N_Block_Statement
then
725 Replace_Returns
(Param_Id
,
726 Statements
(Handled_Statement_Sequence
(Stmt
)));
728 elsif Nkind
(Stmt
) = N_Case_Statement
then
732 Alt
:= First
(Alternatives
(Stmt
));
733 while Present
(Alt
) loop
734 Replace_Returns
(Param_Id
, Statements
(Alt
));
739 elsif Nkind
(Stmt
) = N_Extended_Return_Statement
then
741 Ret_Obj
: constant Entity_Id
:=
743 (First
(Return_Object_Declarations
(Stmt
)));
744 Assign
: constant Node_Id
:=
745 Make_Assignment_Statement
(Sloc
(Stmt
),
747 New_Occurrence_Of
(Param_Id
, Loc
),
749 New_Occurrence_Of
(Ret_Obj
, Sloc
(Stmt
)));
753 -- The extended return may just contain the declaration
755 if Present
(Handled_Statement_Sequence
(Stmt
)) then
756 Stmts
:= Statements
(Handled_Statement_Sequence
(Stmt
));
761 Set_Assignment_OK
(Name
(Assign
));
764 Make_Block_Statement
(Sloc
(Stmt
),
766 Return_Object_Declarations
(Stmt
),
767 Handled_Statement_Sequence
=>
768 Make_Handled_Sequence_Of_Statements
(Loc
,
769 Statements
=> Stmts
)));
771 Replace_Returns
(Param_Id
, Stmts
);
773 Append_To
(Stmts
, Assign
);
774 Append_To
(Stmts
, Make_Simple_Return_Statement
(Loc
));
777 elsif Nkind
(Stmt
) = N_If_Statement
then
778 Replace_Returns
(Param_Id
, Then_Statements
(Stmt
));
779 Replace_Returns
(Param_Id
, Else_Statements
(Stmt
));
784 Part
:= First
(Elsif_Parts
(Stmt
));
785 while Present
(Part
) loop
786 Replace_Returns
(Param_Id
, Then_Statements
(Part
));
791 elsif Nkind
(Stmt
) = N_Loop_Statement
then
792 Replace_Returns
(Param_Id
, Statements
(Stmt
));
794 elsif Nkind
(Stmt
) = N_Simple_Return_Statement
then
801 Make_Assignment_Statement
(Sloc
(Stmt
),
802 Name
=> New_Occurrence_Of
(Param_Id
, Loc
),
803 Expression
=> Relocate_Node
(Expression
(Stmt
))));
805 Insert_After
(Stmt
, Make_Simple_Return_Statement
(Loc
));
807 -- Skip the added return
821 -- Start of processing for Build_Procedure_Body_Form
824 -- This routine replaces the original function body:
826 -- function F (...) return Array_Typ is
832 -- with the following:
834 -- procedure P (..., Result : out Array_Typ) is
837 -- Result := Something;
841 Statements
(Handled_Statement_Sequence
(Func_Body
));
842 Replace_Returns
(Last_Entity
(Proc_Id
), Stmts
);
845 Make_Subprogram_Body
(Loc
,
847 Copy_Subprogram_Spec
(Specification
(Proc_Decl
)),
848 Declarations
=> Declarations
(Func_Body
),
849 Handled_Statement_Sequence
=>
850 Make_Handled_Sequence_Of_Statements
(Loc
,
851 Statements
=> Stmts
));
853 -- If the function is a generic instance, so is the new procedure.
854 -- Set flag accordingly so that the proper renaming declarations are
857 Set_Is_Generic_Instance
(Proc_Id
, Is_Generic_Instance
(Func_Id
));
859 end Build_Procedure_Body_Form
;
861 -----------------------
862 -- Caller_Known_Size --
863 -----------------------
865 function Caller_Known_Size
866 (Func_Call
: Node_Id
;
867 Result_Subt
: Entity_Id
) return Boolean
871 (Is_Definite_Subtype
(Underlying_Type
(Result_Subt
))
872 and then No
(Controlling_Argument
(Func_Call
)))
873 or else not Requires_Transient_Scope
(Underlying_Type
(Result_Subt
));
874 end Caller_Known_Size
;
876 --------------------------------
877 -- Check_Overriding_Operation --
878 --------------------------------
880 procedure Check_Overriding_Operation
(Subp
: Entity_Id
) is
881 Typ
: constant Entity_Id
:= Find_Dispatching_Type
(Subp
);
882 Op_List
: constant Elist_Id
:= Primitive_Operations
(Typ
);
888 if Is_Derived_Type
(Typ
)
889 and then not Is_Private_Type
(Typ
)
890 and then In_Open_Scopes
(Scope
(Etype
(Typ
)))
891 and then Is_Base_Type
(Typ
)
893 -- Subp overrides an inherited private operation if there is an
894 -- inherited operation with a different name than Subp (see
895 -- Derive_Subprogram) whose Alias is a hidden subprogram with the
896 -- same name as Subp.
898 Op_Elmt
:= First_Elmt
(Op_List
);
899 while Present
(Op_Elmt
) loop
900 Prim_Op
:= Node
(Op_Elmt
);
901 Par_Op
:= Alias
(Prim_Op
);
904 and then not Comes_From_Source
(Prim_Op
)
905 and then Chars
(Prim_Op
) /= Chars
(Par_Op
)
906 and then Chars
(Par_Op
) = Chars
(Subp
)
907 and then Is_Hidden
(Par_Op
)
908 and then Type_Conformant
(Prim_Op
, Subp
)
910 Set_DT_Position_Value
(Subp
, DT_Position
(Prim_Op
));
916 end Check_Overriding_Operation
;
918 -------------------------------
919 -- Detect_Infinite_Recursion --
920 -------------------------------
922 procedure Detect_Infinite_Recursion
(N
: Node_Id
; Spec
: Entity_Id
) is
923 Loc
: constant Source_Ptr
:= Sloc
(N
);
925 Var_List
: constant Elist_Id
:= New_Elmt_List
;
926 -- List of globals referenced by body of procedure
928 Call_List
: constant Elist_Id
:= New_Elmt_List
;
929 -- List of recursive calls in body of procedure
931 Shad_List
: constant Elist_Id
:= New_Elmt_List
;
932 -- List of entity id's for entities created to capture the value of
933 -- referenced globals on entry to the procedure.
935 Scop
: constant Uint
:= Scope_Depth
(Spec
);
936 -- This is used to record the scope depth of the current procedure, so
937 -- that we can identify global references.
939 Max_Vars
: constant := 4;
940 -- Do not test more than four global variables
942 Count_Vars
: Natural := 0;
943 -- Count variables found so far
955 function Process
(Nod
: Node_Id
) return Traverse_Result
;
956 -- Function to traverse the subprogram body (using Traverse_Func)
962 function Process
(Nod
: Node_Id
) return Traverse_Result
is
966 if Nkind
(Nod
) = N_Procedure_Call_Statement
then
968 -- Case of one of the detected recursive calls
970 if Is_Entity_Name
(Name
(Nod
))
971 and then Has_Recursive_Call
(Entity
(Name
(Nod
)))
972 and then Entity
(Name
(Nod
)) = Spec
974 Append_Elmt
(Nod
, Call_List
);
977 -- Any other procedure call may have side effects
983 -- A call to a pure function can always be ignored
985 elsif Nkind
(Nod
) = N_Function_Call
986 and then Is_Entity_Name
(Name
(Nod
))
987 and then Is_Pure
(Entity
(Name
(Nod
)))
991 -- Case of an identifier reference
993 elsif Nkind
(Nod
) = N_Identifier
then
996 -- If no entity, then ignore the reference
998 -- Not clear why this can happen. To investigate, remove this
999 -- test and look at the crash that occurs here in 3401-004 ???
1004 -- Ignore entities with no Scope, again not clear how this
1005 -- can happen, to investigate, look at 4108-008 ???
1007 elsif No
(Scope
(Ent
)) then
1010 -- Ignore the reference if not to a more global object
1012 elsif Scope_Depth
(Scope
(Ent
)) >= Scop
then
1015 -- References to types, exceptions and constants are always OK
1018 or else Ekind
(Ent
) = E_Exception
1019 or else Ekind
(Ent
) = E_Constant
1023 -- If other than a non-volatile scalar variable, we have some
1024 -- kind of global reference (e.g. to a function) that we cannot
1025 -- deal with so we forget the attempt.
1027 elsif Ekind
(Ent
) /= E_Variable
1028 or else not Is_Scalar_Type
(Etype
(Ent
))
1029 or else Treat_As_Volatile
(Ent
)
1033 -- Otherwise we have a reference to a global scalar
1036 -- Loop through global entities already detected
1038 Elm
:= First_Elmt
(Var_List
);
1040 -- If not detected before, record this new global reference
1043 Count_Vars
:= Count_Vars
+ 1;
1045 if Count_Vars
<= Max_Vars
then
1046 Append_Elmt
(Entity
(Nod
), Var_List
);
1053 -- If recorded before, ignore
1055 elsif Node
(Elm
) = Entity
(Nod
) then
1058 -- Otherwise keep looking
1068 -- For all other node kinds, recursively visit syntactic children
1075 function Traverse_Body
is new Traverse_Func
(Process
);
1077 -- Start of processing for Detect_Infinite_Recursion
1080 -- Do not attempt detection in No_Implicit_Conditional mode, since we
1081 -- won't be able to generate the code to handle the recursion in any
1084 if Restriction_Active
(No_Implicit_Conditionals
) then
1088 -- Otherwise do traversal and quit if we get abandon signal
1090 if Traverse_Body
(N
) = Abandon
then
1093 -- We must have a call, since Has_Recursive_Call was set. If not just
1094 -- ignore (this is only an error check, so if we have a funny situation,
1095 -- due to bugs or errors, we do not want to bomb).
1097 elsif Is_Empty_Elmt_List
(Call_List
) then
1101 -- Here is the case where we detect recursion at compile time
1103 -- Push our current scope for analyzing the declarations and code that
1104 -- we will insert for the checking.
1108 -- This loop builds temporary variables for each of the referenced
1109 -- globals, so that at the end of the loop the list Shad_List contains
1110 -- these temporaries in one-to-one correspondence with the elements in
1114 Elm
:= First_Elmt
(Var_List
);
1115 while Present
(Elm
) loop
1117 Ent
:= Make_Temporary
(Loc
, 'S');
1118 Append_Elmt
(Ent
, Shad_List
);
1120 -- Insert a declaration for this temporary at the start of the
1121 -- declarations for the procedure. The temporaries are declared as
1122 -- constant objects initialized to the current values of the
1123 -- corresponding temporaries.
1126 Make_Object_Declaration
(Loc
,
1127 Defining_Identifier
=> Ent
,
1128 Object_Definition
=> New_Occurrence_Of
(Etype
(Var
), Loc
),
1129 Constant_Present
=> True,
1130 Expression
=> New_Occurrence_Of
(Var
, Loc
));
1133 Prepend
(Decl
, Declarations
(N
));
1135 Insert_After
(Last
, Decl
);
1143 -- Loop through calls
1145 Call
:= First_Elmt
(Call_List
);
1146 while Present
(Call
) loop
1148 -- Build a predicate expression of the form
1151 -- and then global1 = temp1
1152 -- and then global2 = temp2
1155 -- This predicate determines if any of the global values
1156 -- referenced by the procedure have changed since the
1157 -- current call, if not an infinite recursion is assured.
1159 Test
:= New_Occurrence_Of
(Standard_True
, Loc
);
1161 Elm1
:= First_Elmt
(Var_List
);
1162 Elm2
:= First_Elmt
(Shad_List
);
1163 while Present
(Elm1
) loop
1169 Left_Opnd
=> New_Occurrence_Of
(Node
(Elm1
), Loc
),
1170 Right_Opnd
=> New_Occurrence_Of
(Node
(Elm2
), Loc
)));
1176 -- Now we replace the call with the sequence
1178 -- if no-changes (see above) then
1179 -- raise Storage_Error;
1184 Rewrite
(Node
(Call
),
1185 Make_If_Statement
(Loc
,
1187 Then_Statements
=> New_List
(
1188 Make_Raise_Storage_Error
(Loc
,
1189 Reason
=> SE_Infinite_Recursion
)),
1191 Else_Statements
=> New_List
(
1192 Relocate_Node
(Node
(Call
)))));
1194 Analyze
(Node
(Call
));
1199 -- Remove temporary scope stack entry used for analysis
1202 end Detect_Infinite_Recursion
;
1204 --------------------
1205 -- Expand_Actuals --
1206 --------------------
1208 procedure Expand_Actuals
1211 Post_Call
: out List_Id
)
1213 Loc
: constant Source_Ptr
:= Sloc
(N
);
1217 E_Actual
: Entity_Id
;
1218 E_Formal
: Entity_Id
;
1220 procedure Add_Call_By_Copy_Code
;
1221 -- For cases where the parameter must be passed by copy, this routine
1222 -- generates a temporary variable into which the actual is copied and
1223 -- then passes this as the parameter. For an OUT or IN OUT parameter,
1224 -- an assignment is also generated to copy the result back. The call
1225 -- also takes care of any constraint checks required for the type
1226 -- conversion case (on both the way in and the way out).
1228 procedure Add_Simple_Call_By_Copy_Code
;
1229 -- This is similar to the above, but is used in cases where we know
1230 -- that all that is needed is to simply create a temporary and copy
1231 -- the value in and out of the temporary.
1233 procedure Add_Validation_Call_By_Copy_Code
(Act
: Node_Id
);
1234 -- Perform copy-back for actual parameter Act which denotes a validation
1237 procedure Check_Fortran_Logical
;
1238 -- A value of type Logical that is passed through a formal parameter
1239 -- must be normalized because .TRUE. usually does not have the same
1240 -- representation as True. We assume that .FALSE. = False = 0.
1241 -- What about functions that return a logical type ???
1243 function Is_Legal_Copy
return Boolean;
1244 -- Check that an actual can be copied before generating the temporary
1245 -- to be used in the call. If the actual is of a by_reference type then
1246 -- the program is illegal (this can only happen in the presence of
1247 -- rep. clauses that force an incorrect alignment). If the formal is
1248 -- a by_reference parameter imposed by a DEC pragma, emit a warning to
1249 -- the effect that this might lead to unaligned arguments.
1251 function Make_Var
(Actual
: Node_Id
) return Entity_Id
;
1252 -- Returns an entity that refers to the given actual parameter, Actual
1253 -- (not including any type conversion). If Actual is an entity name,
1254 -- then this entity is returned unchanged, otherwise a renaming is
1255 -- created to provide an entity for the actual.
1257 procedure Reset_Packed_Prefix
;
1258 -- The expansion of a packed array component reference is delayed in
1259 -- the context of a call. Now we need to complete the expansion, so we
1260 -- unmark the analyzed bits in all prefixes.
1262 ---------------------------
1263 -- Add_Call_By_Copy_Code --
1264 ---------------------------
1266 procedure Add_Call_By_Copy_Code
is
1269 F_Typ
: Entity_Id
:= Etype
(Formal
);
1277 if not Is_Legal_Copy
then
1281 Temp
:= Make_Temporary
(Loc
, 'T', Actual
);
1283 -- Handle formals whose type comes from the limited view
1285 if From_Limited_With
(F_Typ
)
1286 and then Has_Non_Limited_View
(F_Typ
)
1288 F_Typ
:= Non_Limited_View
(F_Typ
);
1291 -- Use formal type for temp, unless formal type is an unconstrained
1292 -- array, in which case we don't have to worry about bounds checks,
1293 -- and we use the actual type, since that has appropriate bounds.
1295 if Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
) then
1296 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1298 Indic
:= New_Occurrence_Of
(F_Typ
, Loc
);
1301 if Nkind
(Actual
) = N_Type_Conversion
then
1302 V_Typ
:= Etype
(Expression
(Actual
));
1304 -- If the formal is an (in-)out parameter, capture the name
1305 -- of the variable in order to build the post-call assignment.
1307 Var
:= Make_Var
(Expression
(Actual
));
1309 Crep
:= not Same_Representation
1310 (F_Typ
, Etype
(Expression
(Actual
)));
1313 V_Typ
:= Etype
(Actual
);
1314 Var
:= Make_Var
(Actual
);
1318 -- Setup initialization for case of in out parameter, or an out
1319 -- parameter where the formal is an unconstrained array (in the
1320 -- latter case, we have to pass in an object with bounds).
1322 -- If this is an out parameter, the initial copy is wasteful, so as
1323 -- an optimization for the one-dimensional case we extract the
1324 -- bounds of the actual and build an uninitialized temporary of the
1327 if Ekind
(Formal
) = E_In_Out_Parameter
1328 or else (Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
))
1330 if Nkind
(Actual
) = N_Type_Conversion
then
1331 if Conversion_OK
(Actual
) then
1332 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1334 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1337 elsif Ekind
(Formal
) = E_Out_Parameter
1338 and then Is_Array_Type
(F_Typ
)
1339 and then Number_Dimensions
(F_Typ
) = 1
1340 and then not Has_Non_Null_Base_Init_Proc
(F_Typ
)
1342 -- Actual is a one-dimensional array or slice, and the type
1343 -- requires no initialization. Create a temporary of the
1344 -- right size, but do not copy actual into it (optimization).
1348 Make_Subtype_Indication
(Loc
,
1349 Subtype_Mark
=> New_Occurrence_Of
(F_Typ
, Loc
),
1351 Make_Index_Or_Discriminant_Constraint
(Loc
,
1352 Constraints
=> New_List
(
1355 Make_Attribute_Reference
(Loc
,
1356 Prefix
=> New_Occurrence_Of
(Var
, Loc
),
1357 Attribute_Name
=> Name_First
),
1359 Make_Attribute_Reference
(Loc
,
1360 Prefix
=> New_Occurrence_Of
(Var
, Loc
),
1361 Attribute_Name
=> Name_Last
)))));
1364 Init
:= New_Occurrence_Of
(Var
, Loc
);
1367 -- An initialization is created for packed conversions as
1368 -- actuals for out parameters to enable Make_Object_Declaration
1369 -- to determine the proper subtype for N_Node. Note that this
1370 -- is wasteful because the extra copying on the call side is
1371 -- not required for such out parameters. ???
1373 elsif Ekind
(Formal
) = E_Out_Parameter
1374 and then Nkind
(Actual
) = N_Type_Conversion
1375 and then (Is_Bit_Packed_Array
(F_Typ
)
1377 Is_Bit_Packed_Array
(Etype
(Expression
(Actual
))))
1379 if Conversion_OK
(Actual
) then
1380 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1382 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1385 elsif Ekind
(Formal
) = E_In_Parameter
then
1387 -- Handle the case in which the actual is a type conversion
1389 if Nkind
(Actual
) = N_Type_Conversion
then
1390 if Conversion_OK
(Actual
) then
1391 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1393 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1396 Init
:= New_Occurrence_Of
(Var
, Loc
);
1404 Make_Object_Declaration
(Loc
,
1405 Defining_Identifier
=> Temp
,
1406 Object_Definition
=> Indic
,
1407 Expression
=> Init
);
1408 Set_Assignment_OK
(N_Node
);
1409 Insert_Action
(N
, N_Node
);
1411 -- Now, normally the deal here is that we use the defining
1412 -- identifier created by that object declaration. There is
1413 -- one exception to this. In the change of representation case
1414 -- the above declaration will end up looking like:
1416 -- temp : type := identifier;
1418 -- And in this case we might as well use the identifier directly
1419 -- and eliminate the temporary. Note that the analysis of the
1420 -- declaration was not a waste of time in that case, since it is
1421 -- what generated the necessary change of representation code. If
1422 -- the change of representation introduced additional code, as in
1423 -- a fixed-integer conversion, the expression is not an identifier
1424 -- and must be kept.
1427 and then Present
(Expression
(N_Node
))
1428 and then Is_Entity_Name
(Expression
(N_Node
))
1430 Temp
:= Entity
(Expression
(N_Node
));
1431 Rewrite
(N_Node
, Make_Null_Statement
(Loc
));
1434 -- For IN parameter, all we do is to replace the actual
1436 if Ekind
(Formal
) = E_In_Parameter
then
1437 Rewrite
(Actual
, New_Occurrence_Of
(Temp
, Loc
));
1440 -- Processing for OUT or IN OUT parameter
1443 -- Kill current value indications for the temporary variable we
1444 -- created, since we just passed it as an OUT parameter.
1446 Kill_Current_Values
(Temp
);
1447 Set_Is_Known_Valid
(Temp
, False);
1449 -- If type conversion, use reverse conversion on exit
1451 if Nkind
(Actual
) = N_Type_Conversion
then
1452 if Conversion_OK
(Actual
) then
1453 Expr
:= OK_Convert_To
(V_Typ
, New_Occurrence_Of
(Temp
, Loc
));
1455 Expr
:= Convert_To
(V_Typ
, New_Occurrence_Of
(Temp
, Loc
));
1458 Expr
:= New_Occurrence_Of
(Temp
, Loc
);
1461 Rewrite
(Actual
, New_Occurrence_Of
(Temp
, Loc
));
1464 -- If the actual is a conversion of a packed reference, it may
1465 -- already have been expanded by Remove_Side_Effects, and the
1466 -- resulting variable is a temporary which does not designate
1467 -- the proper out-parameter, which may not be addressable. In
1468 -- that case, generate an assignment to the original expression
1469 -- (before expansion of the packed reference) so that the proper
1470 -- expansion of assignment to a packed component can take place.
1477 if Is_Renaming_Of_Object
(Var
)
1478 and then Nkind
(Renamed_Object
(Var
)) = N_Selected_Component
1479 and then Nkind
(Original_Node
(Prefix
(Renamed_Object
(Var
))))
1480 = N_Indexed_Component
1482 Has_Non_Standard_Rep
(Etype
(Prefix
(Renamed_Object
(Var
))))
1484 Obj
:= Renamed_Object
(Var
);
1486 Make_Selected_Component
(Loc
,
1488 New_Copy_Tree
(Original_Node
(Prefix
(Obj
))),
1489 Selector_Name
=> New_Copy
(Selector_Name
(Obj
)));
1490 Reset_Analyzed_Flags
(Lhs
);
1493 Lhs
:= New_Occurrence_Of
(Var
, Loc
);
1496 Set_Assignment_OK
(Lhs
);
1498 if Is_Access_Type
(E_Formal
)
1499 and then Is_Entity_Name
(Lhs
)
1501 Present
(Effective_Extra_Accessibility
(Entity
(Lhs
)))
1503 -- Copyback target is an Ada 2012 stand-alone object of an
1504 -- anonymous access type.
1506 pragma Assert
(Ada_Version
>= Ada_2012
);
1508 if Type_Access_Level
(E_Formal
) >
1509 Object_Access_Level
(Lhs
)
1511 Append_To
(Post_Call
,
1512 Make_Raise_Program_Error
(Loc
,
1513 Reason
=> PE_Accessibility_Check_Failed
));
1516 Append_To
(Post_Call
,
1517 Make_Assignment_Statement
(Loc
,
1519 Expression
=> Expr
));
1521 -- We would like to somehow suppress generation of the
1522 -- extra_accessibility assignment generated by the expansion
1523 -- of the above assignment statement. It's not a correctness
1524 -- issue because the following assignment renders it dead,
1525 -- but generating back-to-back assignments to the same
1526 -- target is undesirable. ???
1528 Append_To
(Post_Call
,
1529 Make_Assignment_Statement
(Loc
,
1530 Name
=> New_Occurrence_Of
(
1531 Effective_Extra_Accessibility
(Entity
(Lhs
)), Loc
),
1532 Expression
=> Make_Integer_Literal
(Loc
,
1533 Type_Access_Level
(E_Formal
))));
1536 Append_To
(Post_Call
,
1537 Make_Assignment_Statement
(Loc
,
1539 Expression
=> Expr
));
1543 end Add_Call_By_Copy_Code
;
1545 ----------------------------------
1546 -- Add_Simple_Call_By_Copy_Code --
1547 ----------------------------------
1549 procedure Add_Simple_Call_By_Copy_Code
is
1551 F_Typ
: Entity_Id
:= Etype
(Formal
);
1560 if not Is_Legal_Copy
then
1564 -- Handle formals whose type comes from the limited view
1566 if From_Limited_With
(F_Typ
)
1567 and then Has_Non_Limited_View
(F_Typ
)
1569 F_Typ
:= Non_Limited_View
(F_Typ
);
1572 -- Use formal type for temp, unless formal type is an unconstrained
1573 -- array, in which case we don't have to worry about bounds checks,
1574 -- and we use the actual type, since that has appropriate bounds.
1576 if Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
) then
1577 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1579 Indic
:= New_Occurrence_Of
(F_Typ
, Loc
);
1582 -- Prepare to generate code
1584 Reset_Packed_Prefix
;
1586 Temp
:= Make_Temporary
(Loc
, 'T', Actual
);
1587 Incod
:= Relocate_Node
(Actual
);
1588 Outcod
:= New_Copy_Tree
(Incod
);
1590 -- Generate declaration of temporary variable, initializing it
1591 -- with the input parameter unless we have an OUT formal or
1592 -- this is an initialization call.
1594 -- If the formal is an out parameter with discriminants, the
1595 -- discriminants must be captured even if the rest of the object
1596 -- is in principle uninitialized, because the discriminants may
1597 -- be read by the called subprogram.
1599 if Ekind
(Formal
) = E_Out_Parameter
then
1602 if Has_Discriminants
(F_Typ
) then
1603 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1606 elsif Inside_Init_Proc
then
1608 -- Could use a comment here to match comment below ???
1610 if Nkind
(Actual
) /= N_Selected_Component
1612 not Has_Discriminant_Dependent_Constraint
1613 (Entity
(Selector_Name
(Actual
)))
1617 -- Otherwise, keep the component in order to generate the proper
1618 -- actual subtype, that depends on enclosing discriminants.
1626 Make_Object_Declaration
(Loc
,
1627 Defining_Identifier
=> Temp
,
1628 Object_Definition
=> Indic
,
1629 Expression
=> Incod
);
1634 -- If the call is to initialize a component of a composite type,
1635 -- and the component does not depend on discriminants, use the
1636 -- actual type of the component. This is required in case the
1637 -- component is constrained, because in general the formal of the
1638 -- initialization procedure will be unconstrained. Note that if
1639 -- the component being initialized is constrained by an enclosing
1640 -- discriminant, the presence of the initialization in the
1641 -- declaration will generate an expression for the actual subtype.
1643 Set_No_Initialization
(Decl
);
1644 Set_Object_Definition
(Decl
,
1645 New_Occurrence_Of
(Etype
(Actual
), Loc
));
1648 Insert_Action
(N
, Decl
);
1650 -- The actual is simply a reference to the temporary
1652 Rewrite
(Actual
, New_Occurrence_Of
(Temp
, Loc
));
1654 -- Generate copy out if OUT or IN OUT parameter
1656 if Ekind
(Formal
) /= E_In_Parameter
then
1658 Rhs
:= New_Occurrence_Of
(Temp
, Loc
);
1660 -- Deal with conversion
1662 if Nkind
(Lhs
) = N_Type_Conversion
then
1663 Lhs
:= Expression
(Lhs
);
1664 Rhs
:= Convert_To
(Etype
(Actual
), Rhs
);
1667 Append_To
(Post_Call
,
1668 Make_Assignment_Statement
(Loc
,
1670 Expression
=> Rhs
));
1671 Set_Assignment_OK
(Name
(Last
(Post_Call
)));
1673 end Add_Simple_Call_By_Copy_Code
;
1675 --------------------------------------
1676 -- Add_Validation_Call_By_Copy_Code --
1677 --------------------------------------
1679 procedure Add_Validation_Call_By_Copy_Code
(Act
: Node_Id
) is
1682 Obj_Typ
: Entity_Id
;
1683 Var
: constant Node_Id
:= Unqual_Conv
(Act
);
1687 -- Copy the value of the validation variable back into the object
1690 if Is_Entity_Name
(Var
) then
1691 Var_Id
:= Entity
(Var
);
1692 Obj
:= Validated_Object
(Var_Id
);
1693 Obj_Typ
:= Etype
(Obj
);
1695 Expr
:= New_Occurrence_Of
(Var_Id
, Loc
);
1697 -- A type conversion is needed when the validation variable and
1698 -- the validated object carry different types. This case occurs
1699 -- when the actual is qualified in some fashion.
1702 -- subtype Int is Integer range ...;
1703 -- procedure Call (Val : in out Integer);
1707 -- Call (Integer (Object));
1711 -- Var : Integer := Object; -- conversion to base type
1712 -- if not Var'Valid then -- validity check
1713 -- Call (Var); -- modify Var
1714 -- Object := Int (Var); -- conversion to subtype
1716 if Etype
(Var_Id
) /= Obj_Typ
then
1718 Make_Type_Conversion
(Loc
,
1719 Subtype_Mark
=> New_Occurrence_Of
(Obj_Typ
, Loc
),
1720 Expression
=> Expr
);
1726 -- Object := Object_Type (Var);
1728 Append_To
(Post_Call
,
1729 Make_Assignment_Statement
(Loc
,
1731 Expression
=> Expr
));
1733 -- If the flow reaches this point, then this routine was invoked with
1734 -- an actual which does not denote a validation variable.
1737 pragma Assert
(False);
1740 end Add_Validation_Call_By_Copy_Code
;
1742 ---------------------------
1743 -- Check_Fortran_Logical --
1744 ---------------------------
1746 procedure Check_Fortran_Logical
is
1747 Logical
: constant Entity_Id
:= Etype
(Formal
);
1750 -- Note: this is very incomplete, e.g. it does not handle arrays
1751 -- of logical values. This is really not the right approach at all???)
1754 if Convention
(Subp
) = Convention_Fortran
1755 and then Root_Type
(Etype
(Formal
)) = Standard_Boolean
1756 and then Ekind
(Formal
) /= E_In_Parameter
1758 Var
:= Make_Var
(Actual
);
1759 Append_To
(Post_Call
,
1760 Make_Assignment_Statement
(Loc
,
1761 Name
=> New_Occurrence_Of
(Var
, Loc
),
1763 Unchecked_Convert_To
(
1766 Left_Opnd
=> New_Occurrence_Of
(Var
, Loc
),
1768 Unchecked_Convert_To
(
1770 New_Occurrence_Of
(Standard_False
, Loc
))))));
1772 end Check_Fortran_Logical
;
1778 function Is_Legal_Copy
return Boolean is
1780 -- An attempt to copy a value of such a type can only occur if
1781 -- representation clauses give the actual a misaligned address.
1783 if Is_By_Reference_Type
(Etype
(Formal
)) then
1785 -- The actual may in fact be properly aligned but there is not
1786 -- enough front-end information to determine this. In that case
1787 -- gigi will emit an error if a copy is not legal, or generate
1792 -- For users of Starlet, we assume that the specification of by-
1793 -- reference mechanism is mandatory. This may lead to unaligned
1794 -- objects but at least for DEC legacy code it is known to work.
1795 -- The warning will alert users of this code that a problem may
1798 elsif Mechanism
(Formal
) = By_Reference
1799 and then Is_Valued_Procedure
(Scope
(Formal
))
1802 ("by_reference actual may be misaligned??", Actual
);
1814 function Make_Var
(Actual
: Node_Id
) return Entity_Id
is
1818 if Is_Entity_Name
(Actual
) then
1819 return Entity
(Actual
);
1822 Var
:= Make_Temporary
(Loc
, 'T', Actual
);
1825 Make_Object_Renaming_Declaration
(Loc
,
1826 Defining_Identifier
=> Var
,
1828 New_Occurrence_Of
(Etype
(Actual
), Loc
),
1829 Name
=> Relocate_Node
(Actual
));
1831 Insert_Action
(N
, N_Node
);
1836 -------------------------
1837 -- Reset_Packed_Prefix --
1838 -------------------------
1840 procedure Reset_Packed_Prefix
is
1841 Pfx
: Node_Id
:= Actual
;
1844 Set_Analyzed
(Pfx
, False);
1846 not Nkind_In
(Pfx
, N_Selected_Component
, N_Indexed_Component
);
1847 Pfx
:= Prefix
(Pfx
);
1849 end Reset_Packed_Prefix
;
1851 -- Start of processing for Expand_Actuals
1854 Post_Call
:= New_List
;
1856 Formal
:= First_Formal
(Subp
);
1857 Actual
:= First_Actual
(N
);
1858 while Present
(Formal
) loop
1859 E_Formal
:= Etype
(Formal
);
1860 E_Actual
:= Etype
(Actual
);
1862 -- Handle formals whose type comes from the limited view
1864 if From_Limited_With
(E_Formal
)
1865 and then Has_Non_Limited_View
(E_Formal
)
1867 E_Formal
:= Non_Limited_View
(E_Formal
);
1870 if Is_Scalar_Type
(E_Formal
)
1871 or else Nkind
(Actual
) = N_Slice
1873 Check_Fortran_Logical
;
1877 elsif Ekind
(Formal
) /= E_Out_Parameter
then
1879 -- The unusual case of the current instance of a protected type
1880 -- requires special handling. This can only occur in the context
1881 -- of a call within the body of a protected operation.
1883 if Is_Entity_Name
(Actual
)
1884 and then Ekind
(Entity
(Actual
)) = E_Protected_Type
1885 and then In_Open_Scopes
(Entity
(Actual
))
1887 if Scope
(Subp
) /= Entity
(Actual
) then
1889 ("operation outside protected type may not "
1890 & "call back its protected operations??", Actual
);
1894 Expand_Protected_Object_Reference
(N
, Entity
(Actual
)));
1897 -- Ada 2005 (AI-318-02): If the actual parameter is a call to a
1898 -- build-in-place function, then a temporary return object needs
1899 -- to be created and access to it must be passed to the function.
1900 -- Currently we limit such functions to those with inherently
1901 -- limited result subtypes, but eventually we plan to expand the
1902 -- functions that are treated as build-in-place to include other
1903 -- composite result types.
1905 if Is_Build_In_Place_Function_Call
(Actual
) then
1906 Make_Build_In_Place_Call_In_Anonymous_Context
(Actual
);
1908 -- Ada 2005 (AI-318-02): Specialization of the previous case for
1909 -- actuals containing build-in-place function calls whose returned
1910 -- object covers interface types.
1912 elsif Present
(Unqual_BIP_Iface_Function_Call
(Actual
)) then
1913 Make_Build_In_Place_Iface_Call_In_Anonymous_Context
(Actual
);
1916 Apply_Constraint_Check
(Actual
, E_Formal
);
1918 -- Out parameter case. No constraint checks on access type
1921 elsif Is_Access_Type
(E_Formal
) then
1926 elsif Has_Discriminants
(Base_Type
(E_Formal
))
1927 or else Has_Non_Null_Base_Init_Proc
(E_Formal
)
1929 Apply_Constraint_Check
(Actual
, E_Formal
);
1934 Apply_Constraint_Check
(Actual
, Base_Type
(E_Formal
));
1937 -- Processing for IN-OUT and OUT parameters
1939 if Ekind
(Formal
) /= E_In_Parameter
then
1941 -- For type conversions of arrays, apply length/range checks
1943 if Is_Array_Type
(E_Formal
)
1944 and then Nkind
(Actual
) = N_Type_Conversion
1946 if Is_Constrained
(E_Formal
) then
1947 Apply_Length_Check
(Expression
(Actual
), E_Formal
);
1949 Apply_Range_Check
(Expression
(Actual
), E_Formal
);
1953 -- The actual denotes a variable which captures the value of an
1954 -- object for validation purposes. Add a copy-back to reflect any
1955 -- potential changes in value back into the original object.
1957 -- Var : ... := Object;
1958 -- if not Var'Valid then -- validity check
1959 -- Call (Var); -- modify var
1960 -- Object := Var; -- update Object
1962 -- This case is given higher priority because the subsequent check
1963 -- for type conversion may add an extra copy of the variable and
1964 -- prevent proper value propagation back in the original object.
1966 if Is_Validation_Variable_Reference
(Actual
) then
1967 Add_Validation_Call_By_Copy_Code
(Actual
);
1969 -- If argument is a type conversion for a type that is passed by
1970 -- copy, then we must pass the parameter by copy.
1972 elsif Nkind
(Actual
) = N_Type_Conversion
1974 (Is_Numeric_Type
(E_Formal
)
1975 or else Is_Access_Type
(E_Formal
)
1976 or else Is_Enumeration_Type
(E_Formal
)
1977 or else Is_Bit_Packed_Array
(Etype
(Formal
))
1978 or else Is_Bit_Packed_Array
(Etype
(Expression
(Actual
)))
1980 -- Also pass by copy if change of representation
1982 or else not Same_Representation
1984 Etype
(Expression
(Actual
))))
1986 Add_Call_By_Copy_Code
;
1988 -- References to components of bit-packed arrays are expanded
1989 -- at this point, rather than at the point of analysis of the
1990 -- actuals, to handle the expansion of the assignment to
1991 -- [in] out parameters.
1993 elsif Is_Ref_To_Bit_Packed_Array
(Actual
) then
1994 Add_Simple_Call_By_Copy_Code
;
1996 -- If a non-scalar actual is possibly bit-aligned, we need a copy
1997 -- because the back-end cannot cope with such objects. In other
1998 -- cases where alignment forces a copy, the back-end generates
1999 -- it properly. It should not be generated unconditionally in the
2000 -- front-end because it does not know precisely the alignment
2001 -- requirements of the target, and makes too conservative an
2002 -- estimate, leading to superfluous copies or spurious errors
2003 -- on by-reference parameters.
2005 elsif Nkind
(Actual
) = N_Selected_Component
2007 Component_May_Be_Bit_Aligned
(Entity
(Selector_Name
(Actual
)))
2008 and then not Represented_As_Scalar
(Etype
(Formal
))
2010 Add_Simple_Call_By_Copy_Code
;
2012 -- References to slices of bit-packed arrays are expanded
2014 elsif Is_Ref_To_Bit_Packed_Slice
(Actual
) then
2015 Add_Call_By_Copy_Code
;
2017 -- References to possibly unaligned slices of arrays are expanded
2019 elsif Is_Possibly_Unaligned_Slice
(Actual
) then
2020 Add_Call_By_Copy_Code
;
2022 -- Deal with access types where the actual subtype and the
2023 -- formal subtype are not the same, requiring a check.
2025 -- It is necessary to exclude tagged types because of "downward
2026 -- conversion" errors.
2028 elsif Is_Access_Type
(E_Formal
)
2029 and then not Same_Type
(E_Formal
, E_Actual
)
2030 and then not Is_Tagged_Type
(Designated_Type
(E_Formal
))
2032 Add_Call_By_Copy_Code
;
2034 -- If the actual is not a scalar and is marked for volatile
2035 -- treatment, whereas the formal is not volatile, then pass
2036 -- by copy unless it is a by-reference type.
2038 -- Note: we use Is_Volatile here rather than Treat_As_Volatile,
2039 -- because this is the enforcement of a language rule that applies
2040 -- only to "real" volatile variables, not e.g. to the address
2041 -- clause overlay case.
2043 elsif Is_Entity_Name
(Actual
)
2044 and then Is_Volatile
(Entity
(Actual
))
2045 and then not Is_By_Reference_Type
(E_Actual
)
2046 and then not Is_Scalar_Type
(Etype
(Entity
(Actual
)))
2047 and then not Is_Volatile
(E_Formal
)
2049 Add_Call_By_Copy_Code
;
2051 elsif Nkind
(Actual
) = N_Indexed_Component
2052 and then Is_Entity_Name
(Prefix
(Actual
))
2053 and then Has_Volatile_Components
(Entity
(Prefix
(Actual
)))
2055 Add_Call_By_Copy_Code
;
2057 -- Add call-by-copy code for the case of scalar out parameters
2058 -- when it is not known at compile time that the subtype of the
2059 -- formal is a subrange of the subtype of the actual (or vice
2060 -- versa for in out parameters), in order to get range checks
2061 -- on such actuals. (Maybe this case should be handled earlier
2062 -- in the if statement???)
2064 elsif Is_Scalar_Type
(E_Formal
)
2066 (not In_Subrange_Of
(E_Formal
, E_Actual
)
2068 (Ekind
(Formal
) = E_In_Out_Parameter
2069 and then not In_Subrange_Of
(E_Actual
, E_Formal
)))
2071 -- Perhaps the setting back to False should be done within
2072 -- Add_Call_By_Copy_Code, since it could get set on other
2073 -- cases occurring above???
2075 if Do_Range_Check
(Actual
) then
2076 Set_Do_Range_Check
(Actual
, False);
2079 Add_Call_By_Copy_Code
;
2082 -- RM 3.2.4 (23/3): A predicate is checked on in-out and out
2083 -- by-reference parameters on exit from the call. If the actual
2084 -- is a derived type and the operation is inherited, the body
2085 -- of the operation will not contain a call to the predicate
2086 -- function, so it must be done explicitly after the call. Ditto
2087 -- if the actual is an entity of a predicated subtype.
2089 -- The rule refers to by-reference types, but a check is needed
2090 -- for by-copy types as well. That check is subsumed by the rule
2091 -- for subtype conversion on assignment, but we can generate the
2092 -- required check now.
2094 -- Note also that Subp may be either a subprogram entity for
2095 -- direct calls, or a type entity for indirect calls, which must
2096 -- be handled separately because the name does not denote an
2097 -- overloadable entity.
2099 By_Ref_Predicate_Check
: declare
2100 Aund
: constant Entity_Id
:= Underlying_Type
(E_Actual
);
2103 function Is_Public_Subp
return Boolean;
2104 -- Check whether the subprogram being called is a visible
2105 -- operation of the type of the actual. Used to determine
2106 -- whether an invariant check must be generated on the
2109 ---------------------
2110 -- Is_Public_Subp --
2111 ---------------------
2113 function Is_Public_Subp
return Boolean is
2114 Pack
: constant Entity_Id
:= Scope
(Subp
);
2115 Subp_Decl
: Node_Id
;
2118 if not Is_Subprogram
(Subp
) then
2121 -- The operation may be inherited, or a primitive of the
2125 Nkind_In
(Parent
(Subp
), N_Private_Extension_Declaration
,
2126 N_Full_Type_Declaration
)
2128 Subp_Decl
:= Parent
(Subp
);
2131 Subp_Decl
:= Unit_Declaration_Node
(Subp
);
2134 return Ekind
(Pack
) = E_Package
2136 List_Containing
(Subp_Decl
) =
2137 Visible_Declarations
2138 (Specification
(Unit_Declaration_Node
(Pack
)));
2141 -- Start of processing for By_Ref_Predicate_Check
2150 if Has_Predicates
(Atyp
)
2151 and then Present
(Predicate_Function
(Atyp
))
2153 -- Skip predicate checks for special cases
2155 and then Predicate_Tests_On_Arguments
(Subp
)
2157 Append_To
(Post_Call
,
2158 Make_Predicate_Check
(Atyp
, Actual
));
2161 -- We generated caller-side invariant checks in two cases:
2163 -- a) when calling an inherited operation, where there is an
2164 -- implicit view conversion of the actual to the parent type.
2166 -- b) When the conversion is explicit
2168 -- We treat these cases separately because the required
2169 -- conversion for a) is added later when expanding the call.
2171 if Has_Invariants
(Etype
(Actual
))
2173 Nkind
(Parent
(Subp
)) = N_Private_Extension_Declaration
2175 if Comes_From_Source
(N
) and then Is_Public_Subp
then
2176 Append_To
(Post_Call
, Make_Invariant_Call
(Actual
));
2179 elsif Nkind
(Actual
) = N_Type_Conversion
2180 and then Has_Invariants
(Etype
(Expression
(Actual
)))
2182 if Comes_From_Source
(N
) and then Is_Public_Subp
then
2183 Append_To
(Post_Call
,
2184 Make_Invariant_Call
(Expression
(Actual
)));
2187 end By_Ref_Predicate_Check
;
2189 -- Processing for IN parameters
2192 -- For IN parameters in the bit-packed array case, we expand an
2193 -- indexed component (the circuit in Exp_Ch4 deliberately left
2194 -- indexed components appearing as actuals untouched, so that
2195 -- the special processing above for the OUT and IN OUT cases
2196 -- could be performed. We could make the test in Exp_Ch4 more
2197 -- complex and have it detect the parameter mode, but it is
2198 -- easier simply to handle all cases here.)
2200 if Nkind
(Actual
) = N_Indexed_Component
2201 and then Is_Bit_Packed_Array
(Etype
(Prefix
(Actual
)))
2203 Reset_Packed_Prefix
;
2204 Expand_Packed_Element_Reference
(Actual
);
2206 -- If we have a reference to a bit-packed array, we copy it, since
2207 -- the actual must be byte aligned.
2209 -- Is this really necessary in all cases???
2211 elsif Is_Ref_To_Bit_Packed_Array
(Actual
) then
2212 Add_Simple_Call_By_Copy_Code
;
2214 -- If a non-scalar actual is possibly unaligned, we need a copy
2216 elsif Is_Possibly_Unaligned_Object
(Actual
)
2217 and then not Represented_As_Scalar
(Etype
(Formal
))
2219 Add_Simple_Call_By_Copy_Code
;
2221 -- Similarly, we have to expand slices of packed arrays here
2222 -- because the result must be byte aligned.
2224 elsif Is_Ref_To_Bit_Packed_Slice
(Actual
) then
2225 Add_Call_By_Copy_Code
;
2227 -- Only processing remaining is to pass by copy if this is a
2228 -- reference to a possibly unaligned slice, since the caller
2229 -- expects an appropriately aligned argument.
2231 elsif Is_Possibly_Unaligned_Slice
(Actual
) then
2232 Add_Call_By_Copy_Code
;
2234 -- An unusual case: a current instance of an enclosing task can be
2235 -- an actual, and must be replaced by a reference to self.
2237 elsif Is_Entity_Name
(Actual
)
2238 and then Is_Task_Type
(Entity
(Actual
))
2240 if In_Open_Scopes
(Entity
(Actual
)) then
2242 (Make_Function_Call
(Loc
,
2243 Name
=> New_Occurrence_Of
(RTE
(RE_Self
), Loc
))));
2246 -- A task type cannot otherwise appear as an actual
2249 raise Program_Error
;
2254 Next_Formal
(Formal
);
2255 Next_Actual
(Actual
);
2263 procedure Expand_Call
(N
: Node_Id
) is
2264 Post_Call
: List_Id
;
2267 pragma Assert
(Nkind_In
(N
, N_Entry_Call_Statement
,
2269 N_Procedure_Call_Statement
));
2271 Expand_Call_Helper
(N
, Post_Call
);
2272 Insert_Post_Call_Actions
(N
, Post_Call
);
2275 ------------------------
2276 -- Expand_Call_Helper --
2277 ------------------------
2279 -- This procedure handles expansion of function calls and procedure call
2280 -- statements (i.e. it serves as the body for Expand_N_Function_Call and
2281 -- Expand_N_Procedure_Call_Statement). Processing for calls includes:
2283 -- Replace call to Raise_Exception by Raise_Exception_Always if possible
2284 -- Provide values of actuals for all formals in Extra_Formals list
2285 -- Replace "call" to enumeration literal function by literal itself
2286 -- Rewrite call to predefined operator as operator
2287 -- Replace actuals to in-out parameters that are numeric conversions,
2288 -- with explicit assignment to temporaries before and after the call.
2290 -- Note that the list of actuals has been filled with default expressions
2291 -- during semantic analysis of the call. Only the extra actuals required
2292 -- for the 'Constrained attribute and for accessibility checks are added
2295 procedure Expand_Call_Helper
(N
: Node_Id
; Post_Call
: out List_Id
) is
2296 Loc
: constant Source_Ptr
:= Sloc
(N
);
2297 Call_Node
: Node_Id
:= N
;
2298 Extra_Actuals
: List_Id
:= No_List
;
2299 Prev
: Node_Id
:= Empty
;
2301 procedure Add_Actual_Parameter
(Insert_Param
: Node_Id
);
2302 -- Adds one entry to the end of the actual parameter list. Used for
2303 -- default parameters and for extra actuals (for Extra_Formals). The
2304 -- argument is an N_Parameter_Association node.
2306 procedure Add_Extra_Actual
(Expr
: Node_Id
; EF
: Entity_Id
);
2307 -- Adds an extra actual to the list of extra actuals. Expr is the
2308 -- expression for the value of the actual, EF is the entity for the
2311 procedure Add_View_Conversion_Invariants
2312 (Formal
: Entity_Id
;
2314 -- Adds invariant checks for every intermediate type between the range
2315 -- of a view converted argument to its ancestor (from parent to child).
2317 function Inherited_From_Formal
(S
: Entity_Id
) return Entity_Id
;
2318 -- Within an instance, a type derived from an untagged formal derived
2319 -- type inherits from the original parent, not from the actual. The
2320 -- current derivation mechanism has the derived type inherit from the
2321 -- actual, which is only correct outside of the instance. If the
2322 -- subprogram is inherited, we test for this particular case through a
2323 -- convoluted tree traversal before setting the proper subprogram to be
2326 function In_Unfrozen_Instance
(E
: Entity_Id
) return Boolean;
2327 -- Return true if E comes from an instance that is not yet frozen
2329 function Is_Direct_Deep_Call
(Subp
: Entity_Id
) return Boolean;
2330 -- Determine if Subp denotes a non-dispatching call to a Deep routine
2332 function New_Value
(From
: Node_Id
) return Node_Id
;
2333 -- From is the original Expression. New_Value is equivalent to a call
2334 -- to Duplicate_Subexpr with an explicit dereference when From is an
2335 -- access parameter.
2337 --------------------------
2338 -- Add_Actual_Parameter --
2339 --------------------------
2341 procedure Add_Actual_Parameter
(Insert_Param
: Node_Id
) is
2342 Actual_Expr
: constant Node_Id
:=
2343 Explicit_Actual_Parameter
(Insert_Param
);
2346 -- Case of insertion is first named actual
2348 if No
(Prev
) or else
2349 Nkind
(Parent
(Prev
)) /= N_Parameter_Association
2351 Set_Next_Named_Actual
2352 (Insert_Param
, First_Named_Actual
(Call_Node
));
2353 Set_First_Named_Actual
(Call_Node
, Actual_Expr
);
2356 if No
(Parameter_Associations
(Call_Node
)) then
2357 Set_Parameter_Associations
(Call_Node
, New_List
);
2360 Append
(Insert_Param
, Parameter_Associations
(Call_Node
));
2363 Insert_After
(Prev
, Insert_Param
);
2366 -- Case of insertion is not first named actual
2369 Set_Next_Named_Actual
2370 (Insert_Param
, Next_Named_Actual
(Parent
(Prev
)));
2371 Set_Next_Named_Actual
(Parent
(Prev
), Actual_Expr
);
2372 Append
(Insert_Param
, Parameter_Associations
(Call_Node
));
2375 Prev
:= Actual_Expr
;
2376 end Add_Actual_Parameter
;
2378 ----------------------
2379 -- Add_Extra_Actual --
2380 ----------------------
2382 procedure Add_Extra_Actual
(Expr
: Node_Id
; EF
: Entity_Id
) is
2383 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
2386 if Extra_Actuals
= No_List
then
2387 Extra_Actuals
:= New_List
;
2388 Set_Parent
(Extra_Actuals
, Call_Node
);
2391 Append_To
(Extra_Actuals
,
2392 Make_Parameter_Association
(Loc
,
2393 Selector_Name
=> New_Occurrence_Of
(EF
, Loc
),
2394 Explicit_Actual_Parameter
=> Expr
));
2396 Analyze_And_Resolve
(Expr
, Etype
(EF
));
2398 if Nkind
(Call_Node
) = N_Function_Call
then
2399 Set_Is_Accessibility_Actual
(Parent
(Expr
));
2401 end Add_Extra_Actual
;
2403 ------------------------------------
2404 -- Add_View_Conversion_Invariants --
2405 ------------------------------------
2407 procedure Add_View_Conversion_Invariants
2408 (Formal
: Entity_Id
;
2412 Curr_Typ
: Entity_Id
;
2413 Inv_Checks
: List_Id
;
2414 Par_Typ
: Entity_Id
;
2417 Inv_Checks
:= No_List
;
2419 -- Extract the argument from a potentially nested set of view
2423 while Nkind
(Arg
) = N_Type_Conversion
loop
2424 Arg
:= Expression
(Arg
);
2427 -- Move up the derivation chain starting with the type of the formal
2428 -- parameter down to the type of the actual object.
2431 Par_Typ
:= Etype
(Arg
);
2432 while Par_Typ
/= Etype
(Formal
) and Par_Typ
/= Curr_Typ
loop
2433 Curr_Typ
:= Par_Typ
;
2435 if Has_Invariants
(Curr_Typ
)
2436 and then Present
(Invariant_Procedure
(Curr_Typ
))
2438 -- Verify the invariate of the current type. Generate:
2440 -- <Curr_Typ>Invariant (Curr_Typ (Arg));
2442 Prepend_New_To
(Inv_Checks
,
2443 Make_Procedure_Call_Statement
(Loc
,
2446 (Invariant_Procedure
(Curr_Typ
), Loc
),
2447 Parameter_Associations
=> New_List
(
2448 Make_Type_Conversion
(Loc
,
2449 Subtype_Mark
=> New_Occurrence_Of
(Curr_Typ
, Loc
),
2450 Expression
=> New_Copy_Tree
(Arg
)))));
2453 Par_Typ
:= Base_Type
(Etype
(Curr_Typ
));
2456 if not Is_Empty_List
(Inv_Checks
) then
2457 Insert_Actions_After
(N
, Inv_Checks
);
2459 end Add_View_Conversion_Invariants
;
2461 ---------------------------
2462 -- Inherited_From_Formal --
2463 ---------------------------
2465 function Inherited_From_Formal
(S
: Entity_Id
) return Entity_Id
is
2467 Gen_Par
: Entity_Id
;
2468 Gen_Prim
: Elist_Id
;
2473 -- If the operation is inherited, it is attached to the corresponding
2474 -- type derivation. If the parent in the derivation is a generic
2475 -- actual, it is a subtype of the actual, and we have to recover the
2476 -- original derived type declaration to find the proper parent.
2478 if Nkind
(Parent
(S
)) /= N_Full_Type_Declaration
2479 or else not Is_Derived_Type
(Defining_Identifier
(Parent
(S
)))
2480 or else Nkind
(Type_Definition
(Original_Node
(Parent
(S
)))) /=
2481 N_Derived_Type_Definition
2482 or else not In_Instance
2489 (Type_Definition
(Original_Node
(Parent
(S
))));
2491 if Nkind
(Indic
) = N_Subtype_Indication
then
2492 Par
:= Entity
(Subtype_Mark
(Indic
));
2494 Par
:= Entity
(Indic
);
2498 if not Is_Generic_Actual_Type
(Par
)
2499 or else Is_Tagged_Type
(Par
)
2500 or else Nkind
(Parent
(Par
)) /= N_Subtype_Declaration
2501 or else not In_Open_Scopes
(Scope
(Par
))
2505 Gen_Par
:= Generic_Parent_Type
(Parent
(Par
));
2508 -- If the actual has no generic parent type, the formal is not
2509 -- a formal derived type, so nothing to inherit.
2511 if No
(Gen_Par
) then
2515 -- If the generic parent type is still the generic type, this is a
2516 -- private formal, not a derived formal, and there are no operations
2517 -- inherited from the formal.
2519 if Nkind
(Parent
(Gen_Par
)) = N_Formal_Type_Declaration
then
2523 Gen_Prim
:= Collect_Primitive_Operations
(Gen_Par
);
2525 Elmt
:= First_Elmt
(Gen_Prim
);
2526 while Present
(Elmt
) loop
2527 if Chars
(Node
(Elmt
)) = Chars
(S
) then
2533 F1
:= First_Formal
(S
);
2534 F2
:= First_Formal
(Node
(Elmt
));
2536 and then Present
(F2
)
2538 if Etype
(F1
) = Etype
(F2
)
2539 or else Etype
(F2
) = Gen_Par
2545 exit; -- not the right subprogram
2557 raise Program_Error
;
2558 end Inherited_From_Formal
;
2560 --------------------------
2561 -- In_Unfrozen_Instance --
2562 --------------------------
2564 function In_Unfrozen_Instance
(E
: Entity_Id
) return Boolean is
2569 while Present
(S
) and then S
/= Standard_Standard
loop
2570 if Is_Generic_Instance
(S
)
2571 and then Present
(Freeze_Node
(S
))
2572 and then not Analyzed
(Freeze_Node
(S
))
2581 end In_Unfrozen_Instance
;
2583 -------------------------
2584 -- Is_Direct_Deep_Call --
2585 -------------------------
2587 function Is_Direct_Deep_Call
(Subp
: Entity_Id
) return Boolean is
2589 if Is_TSS
(Subp
, TSS_Deep_Adjust
)
2590 or else Is_TSS
(Subp
, TSS_Deep_Finalize
)
2591 or else Is_TSS
(Subp
, TSS_Deep_Initialize
)
2598 Actual
:= First
(Parameter_Associations
(N
));
2599 Formal
:= First_Formal
(Subp
);
2600 while Present
(Actual
)
2601 and then Present
(Formal
)
2603 if Nkind
(Actual
) = N_Identifier
2604 and then Is_Controlling_Actual
(Actual
)
2605 and then Etype
(Actual
) = Etype
(Formal
)
2611 Next_Formal
(Formal
);
2617 end Is_Direct_Deep_Call
;
2623 function New_Value
(From
: Node_Id
) return Node_Id
is
2624 Res
: constant Node_Id
:= Duplicate_Subexpr
(From
);
2626 if Is_Access_Type
(Etype
(From
)) then
2627 return Make_Explicit_Dereference
(Sloc
(From
), Prefix
=> Res
);
2635 Remote
: constant Boolean := Is_Remote_Call
(Call_Node
);
2638 Orig_Subp
: Entity_Id
:= Empty
;
2639 Param_Count
: Natural := 0;
2640 Parent_Formal
: Entity_Id
;
2641 Parent_Subp
: Entity_Id
;
2642 Pref_Entity
: Entity_Id
;
2646 Prev_Orig
: Node_Id
;
2647 -- Original node for an actual, which may have been rewritten. If the
2648 -- actual is a function call that has been transformed from a selected
2649 -- component, the original node is unanalyzed. Otherwise, it carries
2650 -- semantic information used to generate additional actuals.
2652 CW_Interface_Formals_Present
: Boolean := False;
2654 -- Start of processing for Expand_Call_Helper
2657 Post_Call
:= New_List
;
2659 -- Expand the function or procedure call if the first actual has a
2660 -- declared dimension aspect, and the subprogram is declared in one
2661 -- of the dimension I/O packages.
2663 if Ada_Version
>= Ada_2012
2665 Nkind_In
(Call_Node
, N_Procedure_Call_Statement
, N_Function_Call
)
2666 and then Present
(Parameter_Associations
(Call_Node
))
2668 Expand_Put_Call_With_Symbol
(Call_Node
);
2671 -- Ignore if previous error
2673 if Nkind
(Call_Node
) in N_Has_Etype
2674 and then Etype
(Call_Node
) = Any_Type
2679 -- Call using access to subprogram with explicit dereference
2681 if Nkind
(Name
(Call_Node
)) = N_Explicit_Dereference
then
2682 Subp
:= Etype
(Name
(Call_Node
));
2683 Parent_Subp
:= Empty
;
2685 -- Case of call to simple entry, where the Name is a selected component
2686 -- whose prefix is the task, and whose selector name is the entry name
2688 elsif Nkind
(Name
(Call_Node
)) = N_Selected_Component
then
2689 Subp
:= Entity
(Selector_Name
(Name
(Call_Node
)));
2690 Parent_Subp
:= Empty
;
2692 -- Case of call to member of entry family, where Name is an indexed
2693 -- component, with the prefix being a selected component giving the
2694 -- task and entry family name, and the index being the entry index.
2696 elsif Nkind
(Name
(Call_Node
)) = N_Indexed_Component
then
2697 Subp
:= Entity
(Selector_Name
(Prefix
(Name
(Call_Node
))));
2698 Parent_Subp
:= Empty
;
2703 Subp
:= Entity
(Name
(Call_Node
));
2704 Parent_Subp
:= Alias
(Subp
);
2706 -- Replace call to Raise_Exception by call to Raise_Exception_Always
2707 -- if we can tell that the first parameter cannot possibly be null.
2708 -- This improves efficiency by avoiding a run-time test.
2710 -- We do not do this if Raise_Exception_Always does not exist, which
2711 -- can happen in configurable run time profiles which provide only a
2714 if Is_RTE
(Subp
, RE_Raise_Exception
)
2715 and then RTE_Available
(RE_Raise_Exception_Always
)
2718 FA
: constant Node_Id
:=
2719 Original_Node
(First_Actual
(Call_Node
));
2722 -- The case we catch is where the first argument is obtained
2723 -- using the Identity attribute (which must always be
2726 if Nkind
(FA
) = N_Attribute_Reference
2727 and then Attribute_Name
(FA
) = Name_Identity
2729 Subp
:= RTE
(RE_Raise_Exception_Always
);
2730 Set_Name
(Call_Node
, New_Occurrence_Of
(Subp
, Loc
));
2735 if Ekind
(Subp
) = E_Entry
then
2736 Parent_Subp
:= Empty
;
2740 -- Ada 2005 (AI-345): We have a procedure call as a triggering
2741 -- alternative in an asynchronous select or as an entry call in
2742 -- a conditional or timed select. Check whether the procedure call
2743 -- is a renaming of an entry and rewrite it as an entry call.
2745 if Ada_Version
>= Ada_2005
2746 and then Nkind
(Call_Node
) = N_Procedure_Call_Statement
2748 ((Nkind
(Parent
(Call_Node
)) = N_Triggering_Alternative
2749 and then Triggering_Statement
(Parent
(Call_Node
)) = Call_Node
)
2751 (Nkind
(Parent
(Call_Node
)) = N_Entry_Call_Alternative
2752 and then Entry_Call_Statement
(Parent
(Call_Node
)) = Call_Node
))
2756 Ren_Root
: Entity_Id
:= Subp
;
2759 -- This may be a chain of renamings, find the root
2761 if Present
(Alias
(Ren_Root
)) then
2762 Ren_Root
:= Alias
(Ren_Root
);
2765 if Present
(Original_Node
(Parent
(Parent
(Ren_Root
)))) then
2766 Ren_Decl
:= Original_Node
(Parent
(Parent
(Ren_Root
)));
2768 if Nkind
(Ren_Decl
) = N_Subprogram_Renaming_Declaration
then
2770 Make_Entry_Call_Statement
(Loc
,
2772 New_Copy_Tree
(Name
(Ren_Decl
)),
2773 Parameter_Associations
=>
2775 (Parameter_Associations
(Call_Node
))));
2783 if Modify_Tree_For_C
2784 and then Nkind
(Call_Node
) = N_Function_Call
2785 and then Is_Entity_Name
(Name
(Call_Node
))
2788 Func_Id
: constant Entity_Id
:=
2789 Ultimate_Alias
(Entity
(Name
(Call_Node
)));
2791 -- When generating C code, transform a function call that returns
2792 -- a constrained array type into procedure form.
2794 if Rewritten_For_C
(Func_Id
) then
2796 -- For internally generated calls ensure that they reference
2797 -- the entity of the spec of the called function (needed since
2798 -- the expander may generate calls using the entity of their
2799 -- body). See for example Expand_Boolean_Operator().
2801 if not (Comes_From_Source
(Call_Node
))
2802 and then Nkind
(Unit_Declaration_Node
(Func_Id
)) =
2805 Set_Entity
(Name
(Call_Node
),
2806 Corresponding_Function
2807 (Corresponding_Procedure
(Func_Id
)));
2810 Rewrite_Function_Call_For_C
(Call_Node
);
2813 -- Also introduce a temporary for functions that return a record
2814 -- called within another procedure or function call, since records
2815 -- are passed by pointer in the generated C code, and we cannot
2816 -- take a pointer from a subprogram call.
2818 elsif Nkind
(Parent
(Call_Node
)) in N_Subprogram_Call
2819 and then Is_Record_Type
(Etype
(Func_Id
))
2822 Temp_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
2827 -- Temp : ... := Func_Call (...);
2830 Make_Object_Declaration
(Loc
,
2831 Defining_Identifier
=> Temp_Id
,
2832 Object_Definition
=>
2833 New_Occurrence_Of
(Etype
(Func_Id
), Loc
),
2835 Make_Function_Call
(Loc
,
2837 New_Occurrence_Of
(Func_Id
, Loc
),
2838 Parameter_Associations
=>
2839 Parameter_Associations
(Call_Node
)));
2841 Insert_Action
(Parent
(Call_Node
), Decl
);
2842 Rewrite
(Call_Node
, New_Occurrence_Of
(Temp_Id
, Loc
));
2849 -- First step, compute extra actuals, corresponding to any Extra_Formals
2850 -- present. Note that we do not access Extra_Formals directly, instead
2851 -- we simply note the presence of the extra formals as we process the
2852 -- regular formals collecting corresponding actuals in Extra_Actuals.
2854 -- We also generate any required range checks for actuals for in formals
2855 -- as we go through the loop, since this is a convenient place to do it.
2856 -- (Though it seems that this would be better done in Expand_Actuals???)
2858 -- Special case: Thunks must not compute the extra actuals; they must
2859 -- just propagate to the target primitive their extra actuals.
2861 if Is_Thunk
(Current_Scope
)
2862 and then Thunk_Entity
(Current_Scope
) = Subp
2863 and then Present
(Extra_Formals
(Subp
))
2865 pragma Assert
(Present
(Extra_Formals
(Current_Scope
)));
2868 Target_Formal
: Entity_Id
;
2869 Thunk_Formal
: Entity_Id
;
2872 Target_Formal
:= Extra_Formals
(Subp
);
2873 Thunk_Formal
:= Extra_Formals
(Current_Scope
);
2874 while Present
(Target_Formal
) loop
2876 (Expr
=> New_Occurrence_Of
(Thunk_Formal
, Loc
),
2877 EF
=> Thunk_Formal
);
2879 Target_Formal
:= Extra_Formal
(Target_Formal
);
2880 Thunk_Formal
:= Extra_Formal
(Thunk_Formal
);
2883 while Is_Non_Empty_List
(Extra_Actuals
) loop
2884 Add_Actual_Parameter
(Remove_Head
(Extra_Actuals
));
2887 Expand_Actuals
(Call_Node
, Subp
, Post_Call
);
2888 pragma Assert
(Is_Empty_List
(Post_Call
));
2893 Formal
:= First_Formal
(Subp
);
2894 Actual
:= First_Actual
(Call_Node
);
2896 while Present
(Formal
) loop
2898 -- Generate range check if required
2900 if Do_Range_Check
(Actual
)
2901 and then Ekind
(Formal
) = E_In_Parameter
2903 Generate_Range_Check
2904 (Actual
, Etype
(Formal
), CE_Range_Check_Failed
);
2907 -- Prepare to examine current entry
2910 Prev_Orig
:= Original_Node
(Prev
);
2912 -- Ada 2005 (AI-251): Check if any formal is a class-wide interface
2913 -- to expand it in a further round.
2915 CW_Interface_Formals_Present
:=
2916 CW_Interface_Formals_Present
2918 (Is_Class_Wide_Type
(Etype
(Formal
))
2919 and then Is_Interface
(Etype
(Etype
(Formal
))))
2921 (Ekind
(Etype
(Formal
)) = E_Anonymous_Access_Type
2922 and then Is_Class_Wide_Type
(Directly_Designated_Type
2923 (Etype
(Etype
(Formal
))))
2924 and then Is_Interface
(Directly_Designated_Type
2925 (Etype
(Etype
(Formal
)))));
2927 -- Create possible extra actual for constrained case. Usually, the
2928 -- extra actual is of the form actual'constrained, but since this
2929 -- attribute is only available for unconstrained records, TRUE is
2930 -- expanded if the type of the formal happens to be constrained (for
2931 -- instance when this procedure is inherited from an unconstrained
2932 -- record to a constrained one) or if the actual has no discriminant
2933 -- (its type is constrained). An exception to this is the case of a
2934 -- private type without discriminants. In this case we pass FALSE
2935 -- because the object has underlying discriminants with defaults.
2937 if Present
(Extra_Constrained
(Formal
)) then
2938 if Ekind
(Etype
(Prev
)) in Private_Kind
2939 and then not Has_Discriminants
(Base_Type
(Etype
(Prev
)))
2942 (Expr
=> New_Occurrence_Of
(Standard_False
, Loc
),
2943 EF
=> Extra_Constrained
(Formal
));
2945 elsif Is_Constrained
(Etype
(Formal
))
2946 or else not Has_Discriminants
(Etype
(Prev
))
2949 (Expr
=> New_Occurrence_Of
(Standard_True
, Loc
),
2950 EF
=> Extra_Constrained
(Formal
));
2952 -- Do not produce extra actuals for Unchecked_Union parameters.
2953 -- Jump directly to the end of the loop.
2955 elsif Is_Unchecked_Union
(Base_Type
(Etype
(Actual
))) then
2956 goto Skip_Extra_Actual_Generation
;
2959 -- If the actual is a type conversion, then the constrained
2960 -- test applies to the actual, not the target type.
2966 -- Test for unchecked conversions as well, which can occur
2967 -- as out parameter actuals on calls to stream procedures.
2970 while Nkind_In
(Act_Prev
, N_Type_Conversion
,
2971 N_Unchecked_Type_Conversion
)
2973 Act_Prev
:= Expression
(Act_Prev
);
2976 -- If the expression is a conversion of a dereference, this
2977 -- is internally generated code that manipulates addresses,
2978 -- e.g. when building interface tables. No check should
2979 -- occur in this case, and the discriminated object is not
2982 if not Comes_From_Source
(Actual
)
2983 and then Nkind
(Actual
) = N_Unchecked_Type_Conversion
2984 and then Nkind
(Act_Prev
) = N_Explicit_Dereference
2987 (Expr
=> New_Occurrence_Of
(Standard_False
, Loc
),
2988 EF
=> Extra_Constrained
(Formal
));
2993 Make_Attribute_Reference
(Sloc
(Prev
),
2995 Duplicate_Subexpr_No_Checks
2996 (Act_Prev
, Name_Req
=> True),
2997 Attribute_Name
=> Name_Constrained
),
2998 EF
=> Extra_Constrained
(Formal
));
3004 -- Create possible extra actual for accessibility level
3006 if Present
(Extra_Accessibility
(Formal
)) then
3008 -- Ada 2005 (AI-252): If the actual was rewritten as an Access
3009 -- attribute, then the original actual may be an aliased object
3010 -- occurring as the prefix in a call using "Object.Operation"
3011 -- notation. In that case we must pass the level of the object,
3012 -- so Prev_Orig is reset to Prev and the attribute will be
3013 -- processed by the code for Access attributes further below.
3015 if Prev_Orig
/= Prev
3016 and then Nkind
(Prev
) = N_Attribute_Reference
3017 and then Get_Attribute_Id
(Attribute_Name
(Prev
)) =
3019 and then Is_Aliased_View
(Prev_Orig
)
3023 -- A class-wide precondition generates a test in which formals of
3024 -- the subprogram are replaced by actuals that came from source.
3025 -- In that case as well, the accessiblity comes from the actual.
3026 -- This is the one case in which there are references to formals
3027 -- outside of their subprogram.
3029 elsif Prev_Orig
/= Prev
3030 and then Is_Entity_Name
(Prev_Orig
)
3031 and then Present
(Entity
(Prev_Orig
))
3032 and then Is_Formal
(Entity
(Prev_Orig
))
3033 and then not In_Open_Scopes
(Scope
(Entity
(Prev_Orig
)))
3037 -- If the actual is a formal of an enclosing subprogram it is
3038 -- the right entity, even if it is a rewriting. This happens
3039 -- when the call is within an inherited condition or predicate.
3041 elsif Is_Entity_Name
(Actual
)
3042 and then Is_Formal
(Entity
(Actual
))
3043 and then In_Open_Scopes
(Scope
(Entity
(Actual
)))
3047 elsif Nkind
(Prev_Orig
) = N_Type_Conversion
then
3048 Prev_Orig
:= Expression
(Prev_Orig
);
3051 -- Ada 2005 (AI-251): Thunks must propagate the extra actuals of
3052 -- accessibility levels.
3054 if Is_Thunk
(Current_Scope
) then
3056 Parm_Ent
: Entity_Id
;
3059 if Is_Controlling_Actual
(Actual
) then
3061 -- Find the corresponding actual of the thunk
3063 Parm_Ent
:= First_Entity
(Current_Scope
);
3064 for J
in 2 .. Param_Count
loop
3065 Next_Entity
(Parm_Ent
);
3068 -- Handle unchecked conversion of access types generated
3069 -- in thunks (cf. Expand_Interface_Thunk).
3071 elsif Is_Access_Type
(Etype
(Actual
))
3072 and then Nkind
(Actual
) = N_Unchecked_Type_Conversion
3074 Parm_Ent
:= Entity
(Expression
(Actual
));
3076 else pragma Assert
(Is_Entity_Name
(Actual
));
3077 Parm_Ent
:= Entity
(Actual
);
3082 New_Occurrence_Of
(Extra_Accessibility
(Parm_Ent
), Loc
),
3083 EF
=> Extra_Accessibility
(Formal
));
3086 elsif Is_Entity_Name
(Prev_Orig
) then
3088 -- When passing an access parameter, or a renaming of an access
3089 -- parameter, as the actual to another access parameter we need
3090 -- to pass along the actual's own access level parameter. This
3091 -- is done if we are within the scope of the formal access
3092 -- parameter (if this is an inlined body the extra formal is
3095 if (Is_Formal
(Entity
(Prev_Orig
))
3097 (Present
(Renamed_Object
(Entity
(Prev_Orig
)))
3099 Is_Entity_Name
(Renamed_Object
(Entity
(Prev_Orig
)))
3102 (Entity
(Renamed_Object
(Entity
(Prev_Orig
))))))
3103 and then Ekind
(Etype
(Prev_Orig
)) = E_Anonymous_Access_Type
3104 and then In_Open_Scopes
(Scope
(Entity
(Prev_Orig
)))
3107 Parm_Ent
: constant Entity_Id
:= Param_Entity
(Prev_Orig
);
3110 pragma Assert
(Present
(Parm_Ent
));
3112 if Present
(Extra_Accessibility
(Parm_Ent
)) then
3116 (Extra_Accessibility
(Parm_Ent
), Loc
),
3117 EF
=> Extra_Accessibility
(Formal
));
3119 -- If the actual access parameter does not have an
3120 -- associated extra formal providing its scope level,
3121 -- then treat the actual as having library-level
3127 Make_Integer_Literal
(Loc
,
3128 Intval
=> Scope_Depth
(Standard_Standard
)),
3129 EF
=> Extra_Accessibility
(Formal
));
3133 -- The actual is a normal access value, so just pass the level
3134 -- of the actual's access type.
3138 (Expr
=> Dynamic_Accessibility_Level
(Prev_Orig
),
3139 EF
=> Extra_Accessibility
(Formal
));
3142 -- If the actual is an access discriminant, then pass the level
3143 -- of the enclosing object (RM05-3.10.2(12.4/2)).
3145 elsif Nkind
(Prev_Orig
) = N_Selected_Component
3146 and then Ekind
(Entity
(Selector_Name
(Prev_Orig
))) =
3148 and then Ekind
(Etype
(Entity
(Selector_Name
(Prev_Orig
)))) =
3149 E_Anonymous_Access_Type
3153 Make_Integer_Literal
(Loc
,
3154 Intval
=> Object_Access_Level
(Prefix
(Prev_Orig
))),
3155 EF
=> Extra_Accessibility
(Formal
));
3160 case Nkind
(Prev_Orig
) is
3161 when N_Attribute_Reference
=>
3162 case Get_Attribute_Id
(Attribute_Name
(Prev_Orig
)) is
3164 -- For X'Access, pass on the level of the prefix X
3166 when Attribute_Access
=>
3168 -- Accessibility level of S'Access is that of A
3170 Prev_Orig
:= Prefix
(Prev_Orig
);
3172 -- If the expression is a view conversion, the
3173 -- accessibility level is that of the expression.
3175 if Nkind
(Original_Node
(Prev_Orig
)) =
3178 Nkind
(Expression
(Original_Node
(Prev_Orig
))) =
3179 N_Explicit_Dereference
3182 Expression
(Original_Node
(Prev_Orig
));
3185 -- If this is an Access attribute applied to the
3186 -- the current instance object passed to a type
3187 -- initialization procedure, then use the level
3188 -- of the type itself. This is not really correct,
3189 -- as there should be an extra level parameter
3190 -- passed in with _init formals (only in the case
3191 -- where the type is immutably limited), but we
3192 -- don't have an easy way currently to create such
3193 -- an extra formal (init procs aren't ever frozen).
3194 -- For now we just use the level of the type,
3195 -- which may be too shallow, but that works better
3196 -- than passing Object_Access_Level of the type,
3197 -- which can be one level too deep in some cases.
3200 -- A further case that requires special handling
3201 -- is the common idiom E.all'access. If E is a
3202 -- formal of the enclosing subprogram, the
3203 -- accessibility of the expression is that of E.
3205 if Is_Entity_Name
(Prev_Orig
) then
3206 Pref_Entity
:= Entity
(Prev_Orig
);
3208 elsif Nkind
(Prev_Orig
) = N_Explicit_Dereference
3209 and then Is_Entity_Name
(Prefix
(Prev_Orig
))
3211 Pref_Entity
:= Entity
(Prefix
((Prev_Orig
)));
3214 Pref_Entity
:= Empty
;
3217 if Is_Entity_Name
(Prev_Orig
)
3218 and then Is_Type
(Entity
(Prev_Orig
))
3222 Make_Integer_Literal
(Loc
,
3224 Type_Access_Level
(Pref_Entity
)),
3225 EF
=> Extra_Accessibility
(Formal
));
3227 elsif Nkind
(Prev_Orig
) = N_Explicit_Dereference
3228 and then Present
(Pref_Entity
)
3229 and then Is_Formal
(Pref_Entity
)
3231 (Extra_Accessibility
(Pref_Entity
))
3236 (Extra_Accessibility
(Pref_Entity
), Loc
),
3237 EF
=> Extra_Accessibility
(Formal
));
3242 Make_Integer_Literal
(Loc
,
3244 Object_Access_Level
(Prev_Orig
)),
3245 EF
=> Extra_Accessibility
(Formal
));
3248 -- Treat the unchecked attributes as library-level
3250 when Attribute_Unchecked_Access
3251 | Attribute_Unrestricted_Access
3255 Make_Integer_Literal
(Loc
,
3256 Intval
=> Scope_Depth
(Standard_Standard
)),
3257 EF
=> Extra_Accessibility
(Formal
));
3259 -- No other cases of attributes returning access
3260 -- values that can be passed to access parameters.
3263 raise Program_Error
;
3267 -- For allocators we pass the level of the execution of the
3268 -- called subprogram, which is one greater than the current
3274 Make_Integer_Literal
(Loc
,
3275 Intval
=> Scope_Depth
(Current_Scope
) + 1),
3276 EF
=> Extra_Accessibility
(Formal
));
3278 -- For most other cases we simply pass the level of the
3279 -- actual's access type. The type is retrieved from
3280 -- Prev rather than Prev_Orig, because in some cases
3281 -- Prev_Orig denotes an original expression that has
3282 -- not been analyzed.
3286 (Expr
=> Dynamic_Accessibility_Level
(Prev
),
3287 EF
=> Extra_Accessibility
(Formal
));
3292 -- Perform the check of 4.6(49) that prevents a null value from being
3293 -- passed as an actual to an access parameter. Note that the check
3294 -- is elided in the common cases of passing an access attribute or
3295 -- access parameter as an actual. Also, we currently don't enforce
3296 -- this check for expander-generated actuals and when -gnatdj is set.
3298 if Ada_Version
>= Ada_2005
then
3300 -- Ada 2005 (AI-231): Check null-excluding access types. Note that
3301 -- the intent of 6.4.1(13) is that null-exclusion checks should
3302 -- not be done for 'out' parameters, even though it refers only
3303 -- to constraint checks, and a null_exclusion is not a constraint.
3304 -- Note that AI05-0196-1 corrects this mistake in the RM.
3306 if Is_Access_Type
(Etype
(Formal
))
3307 and then Can_Never_Be_Null
(Etype
(Formal
))
3308 and then Ekind
(Formal
) /= E_Out_Parameter
3309 and then Nkind
(Prev
) /= N_Raise_Constraint_Error
3310 and then (Known_Null
(Prev
)
3311 or else not Can_Never_Be_Null
(Etype
(Prev
)))
3313 Install_Null_Excluding_Check
(Prev
);
3316 -- Ada_Version < Ada_2005
3319 if Ekind
(Etype
(Formal
)) /= E_Anonymous_Access_Type
3320 or else Access_Checks_Suppressed
(Subp
)
3324 elsif Debug_Flag_J
then
3327 elsif not Comes_From_Source
(Prev
) then
3330 elsif Is_Entity_Name
(Prev
)
3331 and then Ekind
(Etype
(Prev
)) = E_Anonymous_Access_Type
3335 elsif Nkind_In
(Prev
, N_Allocator
, N_Attribute_Reference
) then
3339 Install_Null_Excluding_Check
(Prev
);
3343 -- Perform appropriate validity checks on parameters that
3346 if Validity_Checks_On
then
3347 if (Ekind
(Formal
) = E_In_Parameter
3348 and then Validity_Check_In_Params
)
3350 (Ekind
(Formal
) = E_In_Out_Parameter
3351 and then Validity_Check_In_Out_Params
)
3353 -- If the actual is an indexed component of a packed type (or
3354 -- is an indexed or selected component whose prefix recursively
3355 -- meets this condition), it has not been expanded yet. It will
3356 -- be copied in the validity code that follows, and has to be
3357 -- expanded appropriately, so reanalyze it.
3359 -- What we do is just to unset analyzed bits on prefixes till
3360 -- we reach something that does not have a prefix.
3367 while Nkind_In
(Nod
, N_Indexed_Component
,
3368 N_Selected_Component
)
3370 Set_Analyzed
(Nod
, False);
3371 Nod
:= Prefix
(Nod
);
3375 Ensure_Valid
(Actual
);
3379 -- For IN OUT and OUT parameters, ensure that subscripts are valid
3380 -- since this is a left side reference. We only do this for calls
3381 -- from the source program since we assume that compiler generated
3382 -- calls explicitly generate any required checks. We also need it
3383 -- only if we are doing standard validity checks, since clearly it is
3384 -- not needed if validity checks are off, and in subscript validity
3385 -- checking mode, all indexed components are checked with a call
3386 -- directly from Expand_N_Indexed_Component.
3388 if Comes_From_Source
(Call_Node
)
3389 and then Ekind
(Formal
) /= E_In_Parameter
3390 and then Validity_Checks_On
3391 and then Validity_Check_Default
3392 and then not Validity_Check_Subscripts
3394 Check_Valid_Lvalue_Subscripts
(Actual
);
3397 -- Mark any scalar OUT parameter that is a simple variable as no
3398 -- longer known to be valid (unless the type is always valid). This
3399 -- reflects the fact that if an OUT parameter is never set in a
3400 -- procedure, then it can become invalid on the procedure return.
3402 if Ekind
(Formal
) = E_Out_Parameter
3403 and then Is_Entity_Name
(Actual
)
3404 and then Ekind
(Entity
(Actual
)) = E_Variable
3405 and then not Is_Known_Valid
(Etype
(Actual
))
3407 Set_Is_Known_Valid
(Entity
(Actual
), False);
3410 -- For an OUT or IN OUT parameter, if the actual is an entity, then
3411 -- clear current values, since they can be clobbered. We are probably
3412 -- doing this in more places than we need to, but better safe than
3413 -- sorry when it comes to retaining bad current values.
3415 if Ekind
(Formal
) /= E_In_Parameter
3416 and then Is_Entity_Name
(Actual
)
3417 and then Present
(Entity
(Actual
))
3420 Ent
: constant Entity_Id
:= Entity
(Actual
);
3424 -- For an OUT or IN OUT parameter that is an assignable entity,
3425 -- we do not want to clobber the Last_Assignment field, since
3426 -- if it is set, it was precisely because it is indeed an OUT
3427 -- or IN OUT parameter. We do reset the Is_Known_Valid flag
3428 -- since the subprogram could have returned in invalid value.
3430 if Ekind_In
(Formal
, E_Out_Parameter
, E_In_Out_Parameter
)
3431 and then Is_Assignable
(Ent
)
3433 Sav
:= Last_Assignment
(Ent
);
3434 Kill_Current_Values
(Ent
);
3435 Set_Last_Assignment
(Ent
, Sav
);
3436 Set_Is_Known_Valid
(Ent
, False);
3438 -- For all other cases, just kill the current values
3441 Kill_Current_Values
(Ent
);
3446 -- If the formal is class wide and the actual is an aggregate, force
3447 -- evaluation so that the back end who does not know about class-wide
3448 -- type, does not generate a temporary of the wrong size.
3450 if not Is_Class_Wide_Type
(Etype
(Formal
)) then
3453 elsif Nkind
(Actual
) = N_Aggregate
3454 or else (Nkind
(Actual
) = N_Qualified_Expression
3455 and then Nkind
(Expression
(Actual
)) = N_Aggregate
)
3457 Force_Evaluation
(Actual
);
3460 -- In a remote call, if the formal is of a class-wide type, check
3461 -- that the actual meets the requirements described in E.4(18).
3463 if Remote
and then Is_Class_Wide_Type
(Etype
(Formal
)) then
3464 Insert_Action
(Actual
,
3465 Make_Transportable_Check
(Loc
,
3466 Duplicate_Subexpr_Move_Checks
(Actual
)));
3469 -- Perform invariant checks for all intermediate types in a view
3470 -- conversion after successful return from a call that passes the
3471 -- view conversion as an IN OUT or OUT parameter (RM 7.3.2 (12/3,
3472 -- 13/3, 14/3)). Consider only source conversion in order to avoid
3473 -- generating spurious checks on complex expansion such as object
3474 -- initialization through an extension aggregate.
3476 if Comes_From_Source
(N
)
3477 and then Ekind
(Formal
) /= E_In_Parameter
3478 and then Nkind
(Actual
) = N_Type_Conversion
3480 Add_View_Conversion_Invariants
(Formal
, Actual
);
3483 -- Generating C the initialization of an allocator is performed by
3484 -- means of individual statements, and hence it must be done before
3487 if Modify_Tree_For_C
3488 and then Nkind
(Actual
) = N_Allocator
3489 and then Nkind
(Expression
(Actual
)) = N_Qualified_Expression
3491 Remove_Side_Effects
(Actual
);
3494 -- This label is required when skipping extra actual generation for
3495 -- Unchecked_Union parameters.
3497 <<Skip_Extra_Actual_Generation
>>
3499 Param_Count
:= Param_Count
+ 1;
3500 Next_Actual
(Actual
);
3501 Next_Formal
(Formal
);
3504 -- If we are calling an Ada 2012 function which needs to have the
3505 -- "accessibility level determined by the point of call" (AI05-0234)
3506 -- passed in to it, then pass it in.
3508 if Ekind_In
(Subp
, E_Function
, E_Operator
, E_Subprogram_Type
)
3510 Present
(Extra_Accessibility_Of_Result
(Ultimate_Alias
(Subp
)))
3513 Ancestor
: Node_Id
:= Parent
(Call_Node
);
3514 Level
: Node_Id
:= Empty
;
3515 Defer
: Boolean := False;
3518 -- Unimplemented: if Subp returns an anonymous access type, then
3520 -- a) if the call is the operand of an explict conversion, then
3521 -- the target type of the conversion (a named access type)
3522 -- determines the accessibility level pass in;
3524 -- b) if the call defines an access discriminant of an object
3525 -- (e.g., the discriminant of an object being created by an
3526 -- allocator, or the discriminant of a function result),
3527 -- then the accessibility level to pass in is that of the
3528 -- discriminated object being initialized).
3532 while Nkind
(Ancestor
) = N_Qualified_Expression
3534 Ancestor
:= Parent
(Ancestor
);
3537 case Nkind
(Ancestor
) is
3540 -- At this point, we'd like to assign
3542 -- Level := Dynamic_Accessibility_Level (Ancestor);
3544 -- but Etype of Ancestor may not have been set yet,
3545 -- so that doesn't work.
3547 -- Handle this later in Expand_Allocator_Expression.
3551 when N_Object_Declaration
3552 | N_Object_Renaming_Declaration
3555 Def_Id
: constant Entity_Id
:=
3556 Defining_Identifier
(Ancestor
);
3559 if Is_Return_Object
(Def_Id
) then
3560 if Present
(Extra_Accessibility_Of_Result
3561 (Return_Applies_To
(Scope
(Def_Id
))))
3563 -- Pass along value that was passed in if the
3564 -- routine we are returning from also has an
3565 -- Accessibility_Of_Result formal.
3569 (Extra_Accessibility_Of_Result
3570 (Return_Applies_To
(Scope
(Def_Id
))), Loc
);
3574 Make_Integer_Literal
(Loc
,
3575 Intval
=> Object_Access_Level
(Def_Id
));
3579 when N_Simple_Return_Statement
=>
3580 if Present
(Extra_Accessibility_Of_Result
3582 (Return_Statement_Entity
(Ancestor
))))
3584 -- Pass along value that was passed in if the returned
3585 -- routine also has an Accessibility_Of_Result formal.
3589 (Extra_Accessibility_Of_Result
3591 (Return_Statement_Entity
(Ancestor
))), Loc
);
3599 if not Present
(Level
) then
3601 -- The "innermost master that evaluates the function call".
3603 -- ??? - Should we use Integer'Last here instead in order
3604 -- to deal with (some of) the problems associated with
3605 -- calls to subps whose enclosing scope is unknown (e.g.,
3606 -- Anon_Access_To_Subp_Param.all)?
3609 Make_Integer_Literal
(Loc
,
3610 Intval
=> Scope_Depth
(Current_Scope
) + 1);
3616 Extra_Accessibility_Of_Result
(Ultimate_Alias
(Subp
)));
3621 -- If we are expanding the RHS of an assignment we need to check if tag
3622 -- propagation is needed. You might expect this processing to be in
3623 -- Analyze_Assignment but has to be done earlier (bottom-up) because the
3624 -- assignment might be transformed to a declaration for an unconstrained
3625 -- value if the expression is classwide.
3627 if Nkind
(Call_Node
) = N_Function_Call
3628 and then Is_Tag_Indeterminate
(Call_Node
)
3629 and then Is_Entity_Name
(Name
(Call_Node
))
3632 Ass
: Node_Id
:= Empty
;
3635 if Nkind
(Parent
(Call_Node
)) = N_Assignment_Statement
then
3636 Ass
:= Parent
(Call_Node
);
3638 elsif Nkind
(Parent
(Call_Node
)) = N_Qualified_Expression
3639 and then Nkind
(Parent
(Parent
(Call_Node
))) =
3640 N_Assignment_Statement
3642 Ass
:= Parent
(Parent
(Call_Node
));
3644 elsif Nkind
(Parent
(Call_Node
)) = N_Explicit_Dereference
3645 and then Nkind
(Parent
(Parent
(Call_Node
))) =
3646 N_Assignment_Statement
3648 Ass
:= Parent
(Parent
(Call_Node
));
3652 and then Is_Class_Wide_Type
(Etype
(Name
(Ass
)))
3654 if Is_Access_Type
(Etype
(Call_Node
)) then
3655 if Designated_Type
(Etype
(Call_Node
)) /=
3656 Root_Type
(Etype
(Name
(Ass
)))
3659 ("tag-indeterminate expression must have designated "
3660 & "type& (RM 5.2 (6))",
3661 Call_Node
, Root_Type
(Etype
(Name
(Ass
))));
3663 Propagate_Tag
(Name
(Ass
), Call_Node
);
3666 elsif Etype
(Call_Node
) /= Root_Type
(Etype
(Name
(Ass
))) then
3668 ("tag-indeterminate expression must have type & "
3670 Call_Node
, Root_Type
(Etype
(Name
(Ass
))));
3673 Propagate_Tag
(Name
(Ass
), Call_Node
);
3676 -- The call will be rewritten as a dispatching call, and
3677 -- expanded as such.
3684 -- Ada 2005 (AI-251): If some formal is a class-wide interface, expand
3685 -- it to point to the correct secondary virtual table
3687 if Nkind
(Call_Node
) in N_Subprogram_Call
3688 and then CW_Interface_Formals_Present
3690 Expand_Interface_Actuals
(Call_Node
);
3693 -- Deals with Dispatch_Call if we still have a call, before expanding
3694 -- extra actuals since this will be done on the re-analysis of the
3695 -- dispatching call. Note that we do not try to shorten the actual list
3696 -- for a dispatching call, it would not make sense to do so. Expansion
3697 -- of dispatching calls is suppressed for VM targets, because the VM
3698 -- back-ends directly handle the generation of dispatching calls and
3699 -- would have to undo any expansion to an indirect call.
3701 if Nkind
(Call_Node
) in N_Subprogram_Call
3702 and then Present
(Controlling_Argument
(Call_Node
))
3705 Call_Typ
: constant Entity_Id
:= Etype
(Call_Node
);
3706 Typ
: constant Entity_Id
:= Find_Dispatching_Type
(Subp
);
3707 Eq_Prim_Op
: Entity_Id
:= Empty
;
3710 Prev_Call
: Node_Id
;
3713 if not Is_Limited_Type
(Typ
) then
3714 Eq_Prim_Op
:= Find_Prim_Op
(Typ
, Name_Op_Eq
);
3717 if Tagged_Type_Expansion
then
3718 Expand_Dispatching_Call
(Call_Node
);
3720 -- The following return is worrisome. Is it really OK to skip
3721 -- all remaining processing in this procedure ???
3728 Apply_Tag_Checks
(Call_Node
);
3730 -- If this is a dispatching "=", we must first compare the
3731 -- tags so we generate: x.tag = y.tag and then x = y
3733 if Subp
= Eq_Prim_Op
then
3735 -- Mark the node as analyzed to avoid reanalyzing this
3736 -- dispatching call (which would cause a never-ending loop)
3738 Prev_Call
:= Relocate_Node
(Call_Node
);
3739 Set_Analyzed
(Prev_Call
);
3741 Param
:= First_Actual
(Call_Node
);
3747 Make_Selected_Component
(Loc
,
3748 Prefix
=> New_Value
(Param
),
3751 (First_Tag_Component
(Typ
), Loc
)),
3754 Make_Selected_Component
(Loc
,
3756 Unchecked_Convert_To
(Typ
,
3757 New_Value
(Next_Actual
(Param
))),
3760 (First_Tag_Component
(Typ
), Loc
))),
3761 Right_Opnd
=> Prev_Call
);
3763 Rewrite
(Call_Node
, New_Call
);
3766 (Call_Node
, Call_Typ
, Suppress
=> All_Checks
);
3769 -- Expansion of a dispatching call results in an indirect call,
3770 -- which in turn causes current values to be killed (see
3771 -- Resolve_Call), so on VM targets we do the call here to
3772 -- ensure consistent warnings between VM and non-VM targets.
3774 Kill_Current_Values
;
3777 -- If this is a dispatching "=" then we must update the reference
3778 -- to the call node because we generated:
3779 -- x.tag = y.tag and then x = y
3781 if Subp
= Eq_Prim_Op
then
3782 Call_Node
:= Right_Opnd
(Call_Node
);
3787 -- Similarly, expand calls to RCI subprograms on which pragma
3788 -- All_Calls_Remote applies. The rewriting will be reanalyzed
3789 -- later. Do this only when the call comes from source since we
3790 -- do not want such a rewriting to occur in expanded code.
3792 if Is_All_Remote_Call
(Call_Node
) then
3793 Expand_All_Calls_Remote_Subprogram_Call
(Call_Node
);
3795 -- Similarly, do not add extra actuals for an entry call whose entity
3796 -- is a protected procedure, or for an internal protected subprogram
3797 -- call, because it will be rewritten as a protected subprogram call
3798 -- and reanalyzed (see Expand_Protected_Subprogram_Call).
3800 elsif Is_Protected_Type
(Scope
(Subp
))
3801 and then (Ekind
(Subp
) = E_Procedure
3802 or else Ekind
(Subp
) = E_Function
)
3806 -- During that loop we gathered the extra actuals (the ones that
3807 -- correspond to Extra_Formals), so now they can be appended.
3810 while Is_Non_Empty_List
(Extra_Actuals
) loop
3811 Add_Actual_Parameter
(Remove_Head
(Extra_Actuals
));
3815 -- At this point we have all the actuals, so this is the point at which
3816 -- the various expansion activities for actuals is carried out.
3818 Expand_Actuals
(Call_Node
, Subp
, Post_Call
);
3820 -- Verify that the actuals do not share storage. This check must be done
3821 -- on the caller side rather that inside the subprogram to avoid issues
3822 -- of parameter passing.
3824 if Check_Aliasing_Of_Parameters
then
3825 Apply_Parameter_Aliasing_Checks
(Call_Node
, Subp
);
3828 -- If the subprogram is a renaming, or if it is inherited, replace it in
3829 -- the call with the name of the actual subprogram being called. If this
3830 -- is a dispatching call, the run-time decides what to call. The Alias
3831 -- attribute does not apply to entries.
3833 if Nkind
(Call_Node
) /= N_Entry_Call_Statement
3834 and then No
(Controlling_Argument
(Call_Node
))
3835 and then Present
(Parent_Subp
)
3836 and then not Is_Direct_Deep_Call
(Subp
)
3838 if Present
(Inherited_From_Formal
(Subp
)) then
3839 Parent_Subp
:= Inherited_From_Formal
(Subp
);
3841 Parent_Subp
:= Ultimate_Alias
(Parent_Subp
);
3844 -- The below setting of Entity is suspect, see F109-018 discussion???
3846 Set_Entity
(Name
(Call_Node
), Parent_Subp
);
3848 if Is_Abstract_Subprogram
(Parent_Subp
)
3849 and then not In_Instance
3852 ("cannot call abstract subprogram &!",
3853 Name
(Call_Node
), Parent_Subp
);
3856 -- Inspect all formals of derived subprogram Subp. Compare parameter
3857 -- types with the parent subprogram and check whether an actual may
3858 -- need a type conversion to the corresponding formal of the parent
3861 -- Not clear whether intrinsic subprograms need such conversions. ???
3863 if not Is_Intrinsic_Subprogram
(Parent_Subp
)
3864 or else Is_Generic_Instance
(Parent_Subp
)
3867 procedure Convert
(Act
: Node_Id
; Typ
: Entity_Id
);
3868 -- Rewrite node Act as a type conversion of Act to Typ. Analyze
3869 -- and resolve the newly generated construct.
3875 procedure Convert
(Act
: Node_Id
; Typ
: Entity_Id
) is
3877 Rewrite
(Act
, OK_Convert_To
(Typ
, Relocate_Node
(Act
)));
3884 Actual_Typ
: Entity_Id
;
3885 Formal_Typ
: Entity_Id
;
3886 Parent_Typ
: Entity_Id
;
3889 Actual
:= First_Actual
(Call_Node
);
3890 Formal
:= First_Formal
(Subp
);
3891 Parent_Formal
:= First_Formal
(Parent_Subp
);
3892 while Present
(Formal
) loop
3893 Actual_Typ
:= Etype
(Actual
);
3894 Formal_Typ
:= Etype
(Formal
);
3895 Parent_Typ
:= Etype
(Parent_Formal
);
3897 -- For an IN parameter of a scalar type, the parent formal
3898 -- type and derived formal type differ or the parent formal
3899 -- type and actual type do not match statically.
3901 if Is_Scalar_Type
(Formal_Typ
)
3902 and then Ekind
(Formal
) = E_In_Parameter
3903 and then Formal_Typ
/= Parent_Typ
3905 not Subtypes_Statically_Match
(Parent_Typ
, Actual_Typ
)
3906 and then not Raises_Constraint_Error
(Actual
)
3908 Convert
(Actual
, Parent_Typ
);
3909 Enable_Range_Check
(Actual
);
3911 -- If the actual has been marked as requiring a range
3912 -- check, then generate it here.
3914 if Do_Range_Check
(Actual
) then
3915 Generate_Range_Check
3916 (Actual
, Etype
(Formal
), CE_Range_Check_Failed
);
3919 -- For access types, the parent formal type and actual type
3922 elsif Is_Access_Type
(Formal_Typ
)
3923 and then Base_Type
(Parent_Typ
) /= Base_Type
(Actual_Typ
)
3925 if Ekind
(Formal
) /= E_In_Parameter
then
3926 Convert
(Actual
, Parent_Typ
);
3928 elsif Ekind
(Parent_Typ
) = E_Anonymous_Access_Type
3929 and then Designated_Type
(Parent_Typ
) /=
3930 Designated_Type
(Actual_Typ
)
3931 and then not Is_Controlling_Formal
(Formal
)
3933 -- This unchecked conversion is not necessary unless
3934 -- inlining is enabled, because in that case the type
3935 -- mismatch may become visible in the body about to be
3939 Unchecked_Convert_To
(Parent_Typ
,
3940 Relocate_Node
(Actual
)));
3942 Resolve
(Actual
, Parent_Typ
);
3945 -- If there is a change of representation, then generate a
3946 -- warning, and do the change of representation.
3948 elsif not Same_Representation
(Formal_Typ
, Parent_Typ
) then
3950 ("??change of representation required", Actual
);
3951 Convert
(Actual
, Parent_Typ
);
3953 -- For array and record types, the parent formal type and
3954 -- derived formal type have different sizes or pragma Pack
3957 elsif ((Is_Array_Type
(Formal_Typ
)
3958 and then Is_Array_Type
(Parent_Typ
))
3960 (Is_Record_Type
(Formal_Typ
)
3961 and then Is_Record_Type
(Parent_Typ
)))
3963 (Esize
(Formal_Typ
) /= Esize
(Parent_Typ
)
3964 or else Has_Pragma_Pack
(Formal_Typ
) /=
3965 Has_Pragma_Pack
(Parent_Typ
))
3967 Convert
(Actual
, Parent_Typ
);
3970 Next_Actual
(Actual
);
3971 Next_Formal
(Formal
);
3972 Next_Formal
(Parent_Formal
);
3978 Subp
:= Parent_Subp
;
3981 -- Deal with case where call is an explicit dereference
3983 if Nkind
(Name
(Call_Node
)) = N_Explicit_Dereference
then
3985 -- Handle case of access to protected subprogram type
3987 if Is_Access_Protected_Subprogram_Type
3988 (Base_Type
(Etype
(Prefix
(Name
(Call_Node
)))))
3990 -- If this is a call through an access to protected operation, the
3991 -- prefix has the form (object'address, operation'access). Rewrite
3992 -- as a for other protected calls: the object is the 1st parameter
3993 -- of the list of actuals.
4000 Ptr
: constant Node_Id
:= Prefix
(Name
(Call_Node
));
4002 T
: constant Entity_Id
:=
4003 Equivalent_Type
(Base_Type
(Etype
(Ptr
)));
4005 D_T
: constant Entity_Id
:=
4006 Designated_Type
(Base_Type
(Etype
(Ptr
)));
4010 Make_Selected_Component
(Loc
,
4011 Prefix
=> Unchecked_Convert_To
(T
, Ptr
),
4013 New_Occurrence_Of
(First_Entity
(T
), Loc
));
4016 Make_Selected_Component
(Loc
,
4017 Prefix
=> Unchecked_Convert_To
(T
, Ptr
),
4019 New_Occurrence_Of
(Next_Entity
(First_Entity
(T
)), Loc
));
4022 Make_Explicit_Dereference
(Loc
,
4025 if Present
(Parameter_Associations
(Call_Node
)) then
4026 Parm
:= Parameter_Associations
(Call_Node
);
4031 Prepend
(Obj
, Parm
);
4033 if Etype
(D_T
) = Standard_Void_Type
then
4035 Make_Procedure_Call_Statement
(Loc
,
4037 Parameter_Associations
=> Parm
);
4040 Make_Function_Call
(Loc
,
4042 Parameter_Associations
=> Parm
);
4045 Set_First_Named_Actual
(Call
, First_Named_Actual
(Call_Node
));
4046 Set_Etype
(Call
, Etype
(D_T
));
4048 -- We do not re-analyze the call to avoid infinite recursion.
4049 -- We analyze separately the prefix and the object, and set
4050 -- the checks on the prefix that would otherwise be emitted
4051 -- when resolving a call.
4053 Rewrite
(Call_Node
, Call
);
4055 Apply_Access_Check
(Nam
);
4062 -- If this is a call to an intrinsic subprogram, then perform the
4063 -- appropriate expansion to the corresponding tree node and we
4064 -- are all done (since after that the call is gone).
4066 -- In the case where the intrinsic is to be processed by the back end,
4067 -- the call to Expand_Intrinsic_Call will do nothing, which is fine,
4068 -- since the idea in this case is to pass the call unchanged. If the
4069 -- intrinsic is an inherited unchecked conversion, and the derived type
4070 -- is the target type of the conversion, we must retain it as the return
4071 -- type of the expression. Otherwise the expansion below, which uses the
4072 -- parent operation, will yield the wrong type.
4074 if Is_Intrinsic_Subprogram
(Subp
) then
4075 Expand_Intrinsic_Call
(Call_Node
, Subp
);
4077 if Nkind
(Call_Node
) = N_Unchecked_Type_Conversion
4078 and then Parent_Subp
/= Orig_Subp
4079 and then Etype
(Parent_Subp
) /= Etype
(Orig_Subp
)
4081 Set_Etype
(Call_Node
, Etype
(Orig_Subp
));
4087 if Ekind_In
(Subp
, E_Function
, E_Procedure
) then
4089 -- We perform a simple optimization on calls for To_Address by
4090 -- replacing them with an unchecked conversion. Not only is this
4091 -- efficient, but it also avoids order of elaboration problems when
4092 -- address clauses are inlined (address expression elaborated at the
4095 -- We perform this optimization regardless of whether we are in the
4096 -- main unit or in a unit in the context of the main unit, to ensure
4097 -- that the generated tree is the same in both cases, for CodePeer
4100 if Is_RTE
(Subp
, RE_To_Address
) then
4102 Unchecked_Convert_To
4103 (RTE
(RE_Address
), Relocate_Node
(First_Actual
(Call_Node
))));
4106 -- A call to a null procedure is replaced by a null statement, but we
4107 -- are not allowed to ignore possible side effects of the call, so we
4108 -- make sure that actuals are evaluated.
4109 -- We also suppress this optimization for GNATCoverage.
4111 elsif Is_Null_Procedure
(Subp
)
4112 and then not Opt
.Suppress_Control_Flow_Optimizations
4114 Actual
:= First_Actual
(Call_Node
);
4115 while Present
(Actual
) loop
4116 Remove_Side_Effects
(Actual
);
4117 Next_Actual
(Actual
);
4120 Rewrite
(Call_Node
, Make_Null_Statement
(Loc
));
4124 -- Handle inlining. No action needed if the subprogram is not inlined
4126 if not Is_Inlined
(Subp
) then
4129 -- Frontend inlining of expression functions (performed also when
4130 -- backend inlining is enabled).
4132 elsif Is_Inlinable_Expression_Function
(Subp
) then
4133 Rewrite
(N
, New_Copy
(Expression_Of_Expression_Function
(Subp
)));
4137 -- Handle frontend inlining
4139 elsif not Back_End_Inlining
then
4140 Inlined_Subprogram
: declare
4142 Must_Inline
: Boolean := False;
4143 Spec
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
4146 -- Verify that the body to inline has already been seen, and
4147 -- that if the body is in the current unit the inlining does
4148 -- not occur earlier. This avoids order-of-elaboration problems
4151 -- This should be documented in sinfo/einfo ???
4154 or else Nkind
(Spec
) /= N_Subprogram_Declaration
4155 or else No
(Body_To_Inline
(Spec
))
4157 Must_Inline
:= False;
4159 -- If this an inherited function that returns a private type,
4160 -- do not inline if the full view is an unconstrained array,
4161 -- because such calls cannot be inlined.
4163 elsif Present
(Orig_Subp
)
4164 and then Is_Array_Type
(Etype
(Orig_Subp
))
4165 and then not Is_Constrained
(Etype
(Orig_Subp
))
4167 Must_Inline
:= False;
4169 elsif In_Unfrozen_Instance
(Scope
(Subp
)) then
4170 Must_Inline
:= False;
4173 Bod
:= Body_To_Inline
(Spec
);
4175 if (In_Extended_Main_Code_Unit
(Call_Node
)
4176 or else In_Extended_Main_Code_Unit
(Parent
(Call_Node
))
4177 or else Has_Pragma_Inline_Always
(Subp
))
4178 and then (not In_Same_Extended_Unit
(Sloc
(Bod
), Loc
)
4180 Earlier_In_Extended_Unit
(Sloc
(Bod
), Loc
))
4182 Must_Inline
:= True;
4184 -- If we are compiling a package body that is not the main
4185 -- unit, it must be for inlining/instantiation purposes,
4186 -- in which case we inline the call to insure that the same
4187 -- temporaries are generated when compiling the body by
4188 -- itself. Otherwise link errors can occur.
4190 -- If the function being called is itself in the main unit,
4191 -- we cannot inline, because there is a risk of double
4192 -- elaboration and/or circularity: the inlining can make
4193 -- visible a private entity in the body of the main unit,
4194 -- that gigi will see before its sees its proper definition.
4196 elsif not (In_Extended_Main_Code_Unit
(Call_Node
))
4197 and then In_Package_Body
4199 Must_Inline
:= not In_Extended_Main_Source_Unit
(Subp
);
4201 -- Inline calls to _postconditions when generating C code
4203 elsif Modify_Tree_For_C
4204 and then In_Same_Extended_Unit
(Sloc
(Bod
), Loc
)
4205 and then Chars
(Name
(N
)) = Name_uPostconditions
4207 Must_Inline
:= True;
4212 Expand_Inlined_Call
(Call_Node
, Subp
, Orig_Subp
);
4215 -- Let the back end handle it
4217 Add_Inlined_Body
(Subp
, Call_Node
);
4219 if Front_End_Inlining
4220 and then Nkind
(Spec
) = N_Subprogram_Declaration
4221 and then (In_Extended_Main_Code_Unit
(Call_Node
))
4222 and then No
(Body_To_Inline
(Spec
))
4223 and then not Has_Completion
(Subp
)
4224 and then In_Same_Extended_Unit
(Sloc
(Spec
), Loc
)
4227 ("cannot inline& (body not seen yet)?",
4231 end Inlined_Subprogram
;
4233 -- Back end inlining: let the back end handle it
4235 elsif No
(Unit_Declaration_Node
(Subp
))
4236 or else Nkind
(Unit_Declaration_Node
(Subp
)) /=
4237 N_Subprogram_Declaration
4238 or else No
(Body_To_Inline
(Unit_Declaration_Node
(Subp
)))
4239 or else Nkind
(Body_To_Inline
(Unit_Declaration_Node
(Subp
))) in
4242 Add_Inlined_Body
(Subp
, Call_Node
);
4244 -- If the inlined call appears within an instantiation and some
4245 -- level of optimization is required, ensure that the enclosing
4246 -- instance body is available so that the back-end can actually
4247 -- perform the inlining.
4250 and then Comes_From_Source
(Subp
)
4251 and then Optimization_Level
> 0
4256 Inst_Node
: Node_Id
;
4259 Inst
:= Scope
(Subp
);
4261 -- Find enclosing instance
4263 while Present
(Inst
) and then Inst
/= Standard_Standard
loop
4264 exit when Is_Generic_Instance
(Inst
);
4265 Inst
:= Scope
(Inst
);
4269 and then Is_Generic_Instance
(Inst
)
4270 and then not Is_Inlined
(Inst
)
4272 Set_Is_Inlined
(Inst
);
4273 Decl
:= Unit_Declaration_Node
(Inst
);
4275 -- Do not add a pending instantiation if the body exits
4276 -- already, or if the instance is a compilation unit, or
4277 -- the instance node is missing.
4279 if Present
(Corresponding_Body
(Decl
))
4280 or else Nkind
(Parent
(Decl
)) = N_Compilation_Unit
4281 or else No
(Next
(Decl
))
4286 -- The instantiation node usually follows the package
4287 -- declaration for the instance. If the generic unit
4288 -- has aspect specifications, they are transformed
4289 -- into pragmas in the instance, and the instance node
4290 -- appears after them.
4292 Inst_Node
:= Next
(Decl
);
4294 while Nkind
(Inst_Node
) /= N_Package_Instantiation
loop
4295 Inst_Node
:= Next
(Inst_Node
);
4298 Add_Pending_Instantiation
(Inst_Node
, Decl
);
4304 -- Front end expansion of simple functions returning unconstrained
4305 -- types (see Check_And_Split_Unconstrained_Function). Note that the
4306 -- case of a simple renaming (Body_To_Inline in N_Entity above, see
4307 -- also Build_Renamed_Body) cannot be expanded here because this may
4308 -- give rise to order-of-elaboration issues for the types of the
4309 -- parameters of the subprogram, if any.
4312 Expand_Inlined_Call
(Call_Node
, Subp
, Orig_Subp
);
4316 -- Check for protected subprogram. This is either an intra-object call,
4317 -- or a protected function call. Protected procedure calls are rewritten
4318 -- as entry calls and handled accordingly.
4320 -- In Ada 2005, this may be an indirect call to an access parameter that
4321 -- is an access_to_subprogram. In that case the anonymous type has a
4322 -- scope that is a protected operation, but the call is a regular one.
4323 -- In either case do not expand call if subprogram is eliminated.
4325 Scop
:= Scope
(Subp
);
4327 if Nkind
(Call_Node
) /= N_Entry_Call_Statement
4328 and then Is_Protected_Type
(Scop
)
4329 and then Ekind
(Subp
) /= E_Subprogram_Type
4330 and then not Is_Eliminated
(Subp
)
4332 -- If the call is an internal one, it is rewritten as a call to the
4333 -- corresponding unprotected subprogram.
4335 Expand_Protected_Subprogram_Call
(Call_Node
, Subp
, Scop
);
4338 -- Functions returning controlled objects need special attention. If
4339 -- the return type is limited, then the context is initialization and
4340 -- different processing applies. If the call is to a protected function,
4341 -- the expansion above will call Expand_Call recursively. Otherwise the
4342 -- function call is transformed into a temporary which obtains the
4343 -- result from the secondary stack.
4345 if Needs_Finalization
(Etype
(Subp
)) then
4346 if not Is_Build_In_Place_Function_Call
(Call_Node
)
4348 (No
(First_Formal
(Subp
))
4350 not Is_Concurrent_Record_Type
(Etype
(First_Formal
(Subp
))))
4352 Expand_Ctrl_Function_Call
(Call_Node
);
4354 -- Build-in-place function calls which appear in anonymous contexts
4355 -- need a transient scope to ensure the proper finalization of the
4356 -- intermediate result after its use.
4358 elsif Is_Build_In_Place_Function_Call
(Call_Node
)
4359 and then Nkind_In
(Parent
(Unqual_Conv
(Call_Node
)),
4360 N_Attribute_Reference
,
4362 N_Indexed_Component
,
4363 N_Object_Renaming_Declaration
,
4364 N_Procedure_Call_Statement
,
4365 N_Selected_Component
,
4368 (Ekind
(Current_Scope
) /= E_Loop
4369 or else Nkind
(Parent
(N
)) /= N_Function_Call
4370 or else not Is_Build_In_Place_Function_Call
(Parent
(N
)))
4372 Establish_Transient_Scope
(Call_Node
, Sec_Stack
=> True);
4375 end Expand_Call_Helper
;
4377 -------------------------------
4378 -- Expand_Ctrl_Function_Call --
4379 -------------------------------
4381 procedure Expand_Ctrl_Function_Call
(N
: Node_Id
) is
4382 function Is_Element_Reference
(N
: Node_Id
) return Boolean;
4383 -- Determine whether node N denotes a reference to an Ada 2012 container
4386 --------------------------
4387 -- Is_Element_Reference --
4388 --------------------------
4390 function Is_Element_Reference
(N
: Node_Id
) return Boolean is
4391 Ref
: constant Node_Id
:= Original_Node
(N
);
4394 -- Analysis marks an element reference by setting the generalized
4395 -- indexing attribute of an indexed component before the component
4396 -- is rewritten into a function call.
4399 Nkind
(Ref
) = N_Indexed_Component
4400 and then Present
(Generalized_Indexing
(Ref
));
4401 end Is_Element_Reference
;
4403 -- Start of processing for Expand_Ctrl_Function_Call
4406 -- Optimization, if the returned value (which is on the sec-stack) is
4407 -- returned again, no need to copy/readjust/finalize, we can just pass
4408 -- the value thru (see Expand_N_Simple_Return_Statement), and thus no
4409 -- attachment is needed
4411 if Nkind
(Parent
(N
)) = N_Simple_Return_Statement
then
4415 -- Resolution is now finished, make sure we don't start analysis again
4416 -- because of the duplication.
4420 -- A function which returns a controlled object uses the secondary
4421 -- stack. Rewrite the call into a temporary which obtains the result of
4422 -- the function using 'reference.
4424 Remove_Side_Effects
(N
);
4426 -- The side effect removal of the function call produced a temporary.
4427 -- When the context is a case expression, if expression, or expression
4428 -- with actions, the lifetime of the temporary must be extended to match
4429 -- that of the context. Otherwise the function result will be finalized
4430 -- too early and affect the result of the expression. To prevent this
4431 -- unwanted effect, the temporary should not be considered for clean up
4432 -- actions by the general finalization machinery.
4434 -- Exception to this rule are references to Ada 2012 container elements.
4435 -- Such references must be finalized at the end of each iteration of the
4436 -- related quantified expression, otherwise the container will remain
4439 if Nkind
(N
) = N_Explicit_Dereference
4440 and then Within_Case_Or_If_Expression
(N
)
4441 and then not Is_Element_Reference
(N
)
4443 Set_Is_Ignored_Transient
(Entity
(Prefix
(N
)));
4445 end Expand_Ctrl_Function_Call
;
4447 ----------------------------------------
4448 -- Expand_N_Extended_Return_Statement --
4449 ----------------------------------------
4451 -- If there is a Handled_Statement_Sequence, we rewrite this:
4453 -- return Result : T := <expression> do
4454 -- <handled_seq_of_stms>
4460 -- Result : T := <expression>;
4462 -- <handled_seq_of_stms>
4466 -- Otherwise (no Handled_Statement_Sequence), we rewrite this:
4468 -- return Result : T := <expression>;
4472 -- return <expression>;
4474 -- unless it's build-in-place or there's no <expression>, in which case
4478 -- Result : T := <expression>;
4483 -- Note that this case could have been written by the user as an extended
4484 -- return statement, or could have been transformed to this from a simple
4485 -- return statement.
4487 -- That is, we need to have a reified return object if there are statements
4488 -- (which might refer to it) or if we're doing build-in-place (so we can
4489 -- set its address to the final resting place or if there is no expression
4490 -- (in which case default initial values might need to be set).
4492 procedure Expand_N_Extended_Return_Statement
(N
: Node_Id
) is
4493 Loc
: constant Source_Ptr
:= Sloc
(N
);
4495 function Build_Heap_Allocator
4496 (Temp_Id
: Entity_Id
;
4497 Temp_Typ
: Entity_Id
;
4498 Func_Id
: Entity_Id
;
4499 Ret_Typ
: Entity_Id
;
4500 Alloc_Expr
: Node_Id
) return Node_Id
;
4501 -- Create the statements necessary to allocate a return object on the
4502 -- caller's master. The master is available through implicit parameter
4503 -- BIPfinalizationmaster.
4505 -- if BIPfinalizationmaster /= null then
4507 -- type Ptr_Typ is access Ret_Typ;
4508 -- for Ptr_Typ'Storage_Pool use
4509 -- Base_Pool (BIPfinalizationmaster.all).all;
4513 -- procedure Allocate (...) is
4515 -- System.Storage_Pools.Subpools.Allocate_Any (...);
4518 -- Local := <Alloc_Expr>;
4519 -- Temp_Id := Temp_Typ (Local);
4523 -- Temp_Id is the temporary which is used to reference the internally
4524 -- created object in all allocation forms. Temp_Typ is the type of the
4525 -- temporary. Func_Id is the enclosing function. Ret_Typ is the return
4526 -- type of Func_Id. Alloc_Expr is the actual allocator.
4528 function Move_Activation_Chain
(Func_Id
: Entity_Id
) return Node_Id
;
4529 -- Construct a call to System.Tasking.Stages.Move_Activation_Chain
4531 -- From current activation chain
4532 -- To activation chain passed in by the caller
4533 -- New_Master master passed in by the caller
4535 -- Func_Id is the entity of the function where the extended return
4536 -- statement appears.
4538 --------------------------
4539 -- Build_Heap_Allocator --
4540 --------------------------
4542 function Build_Heap_Allocator
4543 (Temp_Id
: Entity_Id
;
4544 Temp_Typ
: Entity_Id
;
4545 Func_Id
: Entity_Id
;
4546 Ret_Typ
: Entity_Id
;
4547 Alloc_Expr
: Node_Id
) return Node_Id
4550 pragma Assert
(Is_Build_In_Place_Function
(Func_Id
));
4552 -- Processing for build-in-place object allocation.
4554 if Needs_Finalization
(Ret_Typ
) then
4556 Decls
: constant List_Id
:= New_List
;
4557 Fin_Mas_Id
: constant Entity_Id
:=
4558 Build_In_Place_Formal
4559 (Func_Id
, BIP_Finalization_Master
);
4560 Stmts
: constant List_Id
:= New_List
;
4561 Desig_Typ
: Entity_Id
;
4562 Local_Id
: Entity_Id
;
4563 Pool_Id
: Entity_Id
;
4564 Ptr_Typ
: Entity_Id
;
4568 -- Pool_Id renames Base_Pool (BIPfinalizationmaster.all).all;
4570 Pool_Id
:= Make_Temporary
(Loc
, 'P');
4573 Make_Object_Renaming_Declaration
(Loc
,
4574 Defining_Identifier
=> Pool_Id
,
4576 New_Occurrence_Of
(RTE
(RE_Root_Storage_Pool
), Loc
),
4578 Make_Explicit_Dereference
(Loc
,
4580 Make_Function_Call
(Loc
,
4582 New_Occurrence_Of
(RTE
(RE_Base_Pool
), Loc
),
4583 Parameter_Associations
=> New_List
(
4584 Make_Explicit_Dereference
(Loc
,
4586 New_Occurrence_Of
(Fin_Mas_Id
, Loc
)))))));
4588 -- Create an access type which uses the storage pool of the
4589 -- caller's master. This additional type is necessary because
4590 -- the finalization master cannot be associated with the type
4591 -- of the temporary. Otherwise the secondary stack allocation
4594 Desig_Typ
:= Ret_Typ
;
4596 -- Ensure that the build-in-place machinery uses a fat pointer
4597 -- when allocating an unconstrained array on the heap. In this
4598 -- case the result object type is a constrained array type even
4599 -- though the function type is unconstrained.
4601 if Ekind
(Desig_Typ
) = E_Array_Subtype
then
4602 Desig_Typ
:= Base_Type
(Desig_Typ
);
4606 -- type Ptr_Typ is access Desig_Typ;
4608 Ptr_Typ
:= Make_Temporary
(Loc
, 'P');
4611 Make_Full_Type_Declaration
(Loc
,
4612 Defining_Identifier
=> Ptr_Typ
,
4614 Make_Access_To_Object_Definition
(Loc
,
4615 Subtype_Indication
=>
4616 New_Occurrence_Of
(Desig_Typ
, Loc
))));
4618 -- Perform minor decoration in order to set the master and the
4619 -- storage pool attributes.
4621 Set_Ekind
(Ptr_Typ
, E_Access_Type
);
4622 Set_Finalization_Master
(Ptr_Typ
, Fin_Mas_Id
);
4623 Set_Associated_Storage_Pool
(Ptr_Typ
, Pool_Id
);
4625 -- Create the temporary, generate:
4626 -- Local_Id : Ptr_Typ;
4628 Local_Id
:= Make_Temporary
(Loc
, 'T');
4631 Make_Object_Declaration
(Loc
,
4632 Defining_Identifier
=> Local_Id
,
4633 Object_Definition
=>
4634 New_Occurrence_Of
(Ptr_Typ
, Loc
)));
4636 -- Allocate the object, generate:
4637 -- Local_Id := <Alloc_Expr>;
4640 Make_Assignment_Statement
(Loc
,
4641 Name
=> New_Occurrence_Of
(Local_Id
, Loc
),
4642 Expression
=> Alloc_Expr
));
4645 -- Temp_Id := Temp_Typ (Local_Id);
4648 Make_Assignment_Statement
(Loc
,
4649 Name
=> New_Occurrence_Of
(Temp_Id
, Loc
),
4651 Unchecked_Convert_To
(Temp_Typ
,
4652 New_Occurrence_Of
(Local_Id
, Loc
))));
4654 -- Wrap the allocation in a block. This is further conditioned
4655 -- by checking the caller finalization master at runtime. A
4656 -- null value indicates a non-existent master, most likely due
4657 -- to a Finalize_Storage_Only allocation.
4660 -- if BIPfinalizationmaster /= null then
4669 Make_If_Statement
(Loc
,
4672 Left_Opnd
=> New_Occurrence_Of
(Fin_Mas_Id
, Loc
),
4673 Right_Opnd
=> Make_Null
(Loc
)),
4675 Then_Statements
=> New_List
(
4676 Make_Block_Statement
(Loc
,
4677 Declarations
=> Decls
,
4678 Handled_Statement_Sequence
=>
4679 Make_Handled_Sequence_Of_Statements
(Loc
,
4680 Statements
=> Stmts
))));
4683 -- For all other cases, generate:
4684 -- Temp_Id := <Alloc_Expr>;
4688 Make_Assignment_Statement
(Loc
,
4689 Name
=> New_Occurrence_Of
(Temp_Id
, Loc
),
4690 Expression
=> Alloc_Expr
);
4692 end Build_Heap_Allocator
;
4694 ---------------------------
4695 -- Move_Activation_Chain --
4696 ---------------------------
4698 function Move_Activation_Chain
(Func_Id
: Entity_Id
) return Node_Id
is
4701 Make_Procedure_Call_Statement
(Loc
,
4703 New_Occurrence_Of
(RTE
(RE_Move_Activation_Chain
), Loc
),
4705 Parameter_Associations
=> New_List
(
4709 Make_Attribute_Reference
(Loc
,
4710 Prefix
=> Make_Identifier
(Loc
, Name_uChain
),
4711 Attribute_Name
=> Name_Unrestricted_Access
),
4713 -- Destination chain
4716 (Build_In_Place_Formal
(Func_Id
, BIP_Activation_Chain
), Loc
),
4721 (Build_In_Place_Formal
(Func_Id
, BIP_Task_Master
), Loc
)));
4722 end Move_Activation_Chain
;
4726 Func_Id
: constant Entity_Id
:=
4727 Return_Applies_To
(Return_Statement_Entity
(N
));
4728 Is_BIP_Func
: constant Boolean :=
4729 Is_Build_In_Place_Function
(Func_Id
);
4730 Ret_Obj_Id
: constant Entity_Id
:=
4731 First_Entity
(Return_Statement_Entity
(N
));
4732 Ret_Obj_Decl
: constant Node_Id
:= Parent
(Ret_Obj_Id
);
4733 Ret_Typ
: constant Entity_Id
:= Etype
(Func_Id
);
4740 Return_Stmt
: Node_Id
:= Empty
;
4741 -- Force initialization to facilitate static analysis
4743 -- Start of processing for Expand_N_Extended_Return_Statement
4746 -- Given that functionality of interface thunks is simple (just displace
4747 -- the pointer to the object) they are always handled by means of
4748 -- simple return statements.
4750 pragma Assert
(not Is_Thunk
(Current_Scope
));
4752 if Nkind
(Ret_Obj_Decl
) = N_Object_Declaration
then
4753 Exp
:= Expression
(Ret_Obj_Decl
);
4755 -- Assert that if F says "return R : T := G(...) do..."
4756 -- then F and G are both b-i-p, or neither b-i-p.
4758 if Nkind
(Exp
) = N_Function_Call
then
4759 pragma Assert
(Ekind
(Current_Scope
) = E_Function
);
4761 (Is_Build_In_Place_Function
(Current_Scope
) =
4762 Is_Build_In_Place_Function_Call
(Exp
));
4769 HSS
:= Handled_Statement_Sequence
(N
);
4771 -- If the returned object needs finalization actions, the function must
4772 -- perform the appropriate cleanup should it fail to return. The state
4773 -- of the function itself is tracked through a flag which is coupled
4774 -- with the scope finalizer. There is one flag per each return object
4775 -- in case of multiple returns.
4777 if Is_BIP_Func
and then Needs_Finalization
(Etype
(Ret_Obj_Id
)) then
4779 Flag_Decl
: Node_Id
;
4780 Flag_Id
: Entity_Id
;
4784 -- Recover the function body
4786 Func_Bod
:= Unit_Declaration_Node
(Func_Id
);
4788 if Nkind
(Func_Bod
) = N_Subprogram_Declaration
then
4789 Func_Bod
:= Parent
(Parent
(Corresponding_Body
(Func_Bod
)));
4792 if Nkind
(Func_Bod
) = N_Function_Specification
then
4793 Func_Bod
:= Parent
(Func_Bod
); -- one more level for child units
4796 pragma Assert
(Nkind
(Func_Bod
) = N_Subprogram_Body
);
4798 -- Create a flag to track the function state
4800 Flag_Id
:= Make_Temporary
(Loc
, 'F');
4801 Set_Status_Flag_Or_Transient_Decl
(Ret_Obj_Id
, Flag_Id
);
4803 -- Insert the flag at the beginning of the function declarations,
4805 -- Fnn : Boolean := False;
4808 Make_Object_Declaration
(Loc
,
4809 Defining_Identifier
=> Flag_Id
,
4810 Object_Definition
=>
4811 New_Occurrence_Of
(Standard_Boolean
, Loc
),
4813 New_Occurrence_Of
(Standard_False
, Loc
));
4815 Prepend_To
(Declarations
(Func_Bod
), Flag_Decl
);
4816 Analyze
(Flag_Decl
);
4820 -- Build a simple_return_statement that returns the return object when
4821 -- there is a statement sequence, or no expression, or the result will
4822 -- be built in place. Note however that we currently do this for all
4823 -- composite cases, even though not all are built in place.
4826 or else Is_Composite_Type
(Ret_Typ
)
4832 -- If the extended return has a handled statement sequence, then wrap
4833 -- it in a block and use the block as the first statement.
4837 Make_Block_Statement
(Loc
,
4838 Declarations
=> New_List
,
4839 Handled_Statement_Sequence
=> HSS
));
4842 -- If the result type contains tasks, we call Move_Activation_Chain.
4843 -- Later, the cleanup code will call Complete_Master, which will
4844 -- terminate any unactivated tasks belonging to the return statement
4845 -- master. But Move_Activation_Chain updates their master to be that
4846 -- of the caller, so they will not be terminated unless the return
4847 -- statement completes unsuccessfully due to exception, abort, goto,
4848 -- or exit. As a formality, we test whether the function requires the
4849 -- result to be built in place, though that's necessarily true for
4850 -- the case of result types with task parts.
4852 if Is_BIP_Func
and then Has_Task
(Ret_Typ
) then
4854 -- The return expression is an aggregate for a complex type which
4855 -- contains tasks. This particular case is left unexpanded since
4856 -- the regular expansion would insert all temporaries and
4857 -- initialization code in the wrong block.
4859 if Nkind
(Exp
) = N_Aggregate
then
4860 Expand_N_Aggregate
(Exp
);
4863 -- Do not move the activation chain if the return object does not
4866 if Has_Task
(Etype
(Ret_Obj_Id
)) then
4867 Append_To
(Stmts
, Move_Activation_Chain
(Func_Id
));
4871 -- Update the state of the function right before the object is
4874 if Is_BIP_Func
and then Needs_Finalization
(Etype
(Ret_Obj_Id
)) then
4876 Flag_Id
: constant Entity_Id
:=
4877 Status_Flag_Or_Transient_Decl
(Ret_Obj_Id
);
4884 Make_Assignment_Statement
(Loc
,
4885 Name
=> New_Occurrence_Of
(Flag_Id
, Loc
),
4886 Expression
=> New_Occurrence_Of
(Standard_True
, Loc
)));
4890 -- Build a simple_return_statement that returns the return object
4893 Make_Simple_Return_Statement
(Loc
,
4894 Expression
=> New_Occurrence_Of
(Ret_Obj_Id
, Loc
));
4895 Append_To
(Stmts
, Return_Stmt
);
4897 HSS
:= Make_Handled_Sequence_Of_Statements
(Loc
, Stmts
);
4900 -- Case where we build a return statement block
4902 if Present
(HSS
) then
4904 Make_Block_Statement
(Loc
,
4905 Declarations
=> Return_Object_Declarations
(N
),
4906 Handled_Statement_Sequence
=> HSS
);
4908 -- We set the entity of the new block statement to be that of the
4909 -- return statement. This is necessary so that various fields, such
4910 -- as Finalization_Chain_Entity carry over from the return statement
4911 -- to the block. Note that this block is unusual, in that its entity
4912 -- is an E_Return_Statement rather than an E_Block.
4915 (Result
, New_Occurrence_Of
(Return_Statement_Entity
(N
), Loc
));
4917 -- If the object decl was already rewritten as a renaming, then we
4918 -- don't want to do the object allocation and transformation of
4919 -- the return object declaration to a renaming. This case occurs
4920 -- when the return object is initialized by a call to another
4921 -- build-in-place function, and that function is responsible for
4922 -- the allocation of the return object.
4925 and then Nkind
(Ret_Obj_Decl
) = N_Object_Renaming_Declaration
4928 (Nkind
(Original_Node
(Ret_Obj_Decl
)) = N_Object_Declaration
4931 -- It is a regular BIP object declaration
4933 (Is_Build_In_Place_Function_Call
4934 (Expression
(Original_Node
(Ret_Obj_Decl
)))
4936 -- It is a BIP object declaration that displaces the pointer
4937 -- to the object to reference a convered interface type.
4940 Present
(Unqual_BIP_Iface_Function_Call
4941 (Expression
(Original_Node
(Ret_Obj_Decl
))))));
4943 -- Return the build-in-place result by reference
4945 Set_By_Ref
(Return_Stmt
);
4947 elsif Is_BIP_Func
then
4949 -- Locate the implicit access parameter associated with the
4950 -- caller-supplied return object and convert the return
4951 -- statement's return object declaration to a renaming of a
4952 -- dereference of the access parameter. If the return object's
4953 -- declaration includes an expression that has not already been
4954 -- expanded as separate assignments, then add an assignment
4955 -- statement to ensure the return object gets initialized.
4958 -- Result : T [:= <expression>];
4965 -- Result : T renames FuncRA.all;
4966 -- [Result := <expression;]
4971 Ret_Obj_Expr
: constant Node_Id
:= Expression
(Ret_Obj_Decl
);
4972 Ret_Obj_Typ
: constant Entity_Id
:= Etype
(Ret_Obj_Id
);
4974 Init_Assignment
: Node_Id
:= Empty
;
4975 Obj_Acc_Formal
: Entity_Id
;
4976 Obj_Acc_Deref
: Node_Id
;
4977 Obj_Alloc_Formal
: Entity_Id
;
4980 -- Build-in-place results must be returned by reference
4982 Set_By_Ref
(Return_Stmt
);
4984 -- Retrieve the implicit access parameter passed by the caller
4987 Build_In_Place_Formal
(Func_Id
, BIP_Object_Access
);
4989 -- If the return object's declaration includes an expression
4990 -- and the declaration isn't marked as No_Initialization, then
4991 -- we need to generate an assignment to the object and insert
4992 -- it after the declaration before rewriting it as a renaming
4993 -- (otherwise we'll lose the initialization). The case where
4994 -- the result type is an interface (or class-wide interface)
4995 -- is also excluded because the context of the function call
4996 -- must be unconstrained, so the initialization will always
4997 -- be done as part of an allocator evaluation (storage pool
4998 -- or secondary stack), never to a constrained target object
4999 -- passed in by the caller. Besides the assignment being
5000 -- unneeded in this case, it avoids problems with trying to
5001 -- generate a dispatching assignment when the return expression
5002 -- is a nonlimited descendant of a limited interface (the
5003 -- interface has no assignment operation).
5005 if Present
(Ret_Obj_Expr
)
5006 and then not No_Initialization
(Ret_Obj_Decl
)
5007 and then not Is_Interface
(Ret_Obj_Typ
)
5010 Make_Assignment_Statement
(Loc
,
5011 Name
=> New_Occurrence_Of
(Ret_Obj_Id
, Loc
),
5012 Expression
=> New_Copy_Tree
(Ret_Obj_Expr
));
5014 Set_Etype
(Name
(Init_Assignment
), Etype
(Ret_Obj_Id
));
5015 Set_Assignment_OK
(Name
(Init_Assignment
));
5016 Set_No_Ctrl_Actions
(Init_Assignment
);
5018 Set_Parent
(Name
(Init_Assignment
), Init_Assignment
);
5019 Set_Parent
(Expression
(Init_Assignment
), Init_Assignment
);
5021 Set_Expression
(Ret_Obj_Decl
, Empty
);
5023 if Is_Class_Wide_Type
(Etype
(Ret_Obj_Id
))
5024 and then not Is_Class_Wide_Type
5025 (Etype
(Expression
(Init_Assignment
)))
5027 Rewrite
(Expression
(Init_Assignment
),
5028 Make_Type_Conversion
(Loc
,
5030 New_Occurrence_Of
(Etype
(Ret_Obj_Id
), Loc
),
5032 Relocate_Node
(Expression
(Init_Assignment
))));
5035 -- In the case of functions where the calling context can
5036 -- determine the form of allocation needed, initialization
5037 -- is done with each part of the if statement that handles
5038 -- the different forms of allocation (this is true for
5039 -- unconstrained and tagged result subtypes).
5041 if Is_Constrained
(Ret_Typ
)
5042 and then not Is_Tagged_Type
(Underlying_Type
(Ret_Typ
))
5044 Insert_After
(Ret_Obj_Decl
, Init_Assignment
);
5048 -- When the function's subtype is unconstrained, a run-time
5049 -- test is needed to determine the form of allocation to use
5050 -- for the return object. The function has an implicit formal
5051 -- parameter indicating this. If the BIP_Alloc_Form formal has
5052 -- the value one, then the caller has passed access to an
5053 -- existing object for use as the return object. If the value
5054 -- is two, then the return object must be allocated on the
5055 -- secondary stack. Otherwise, the object must be allocated in
5056 -- a storage pool. We generate an if statement to test the
5057 -- implicit allocation formal and initialize a local access
5058 -- value appropriately, creating allocators in the secondary
5059 -- stack and global heap cases. The special formal also exists
5060 -- and must be tested when the function has a tagged result,
5061 -- even when the result subtype is constrained, because in
5062 -- general such functions can be called in dispatching contexts
5063 -- and must be handled similarly to functions with a class-wide
5066 if not Is_Constrained
(Ret_Typ
)
5067 or else Is_Tagged_Type
(Underlying_Type
(Ret_Typ
))
5070 Build_In_Place_Formal
(Func_Id
, BIP_Alloc_Form
);
5073 Pool_Id
: constant Entity_Id
:=
5074 Make_Temporary
(Loc
, 'P');
5075 Alloc_Obj_Id
: Entity_Id
;
5076 Alloc_Obj_Decl
: Node_Id
;
5077 Alloc_If_Stmt
: Node_Id
;
5078 Heap_Allocator
: Node_Id
;
5079 Pool_Decl
: Node_Id
;
5080 Pool_Allocator
: Node_Id
;
5081 Ptr_Type_Decl
: Node_Id
;
5082 Ref_Type
: Entity_Id
;
5083 SS_Allocator
: Node_Id
;
5086 -- Reuse the itype created for the function's implicit
5087 -- access formal. This avoids the need to create a new
5088 -- access type here, plus it allows assigning the access
5089 -- formal directly without applying a conversion.
5091 -- Ref_Type := Etype (Object_Access);
5093 -- Create an access type designating the function's
5096 Ref_Type
:= Make_Temporary
(Loc
, 'A');
5099 Make_Full_Type_Declaration
(Loc
,
5100 Defining_Identifier
=> Ref_Type
,
5102 Make_Access_To_Object_Definition
(Loc
,
5103 All_Present
=> True,
5104 Subtype_Indication
=>
5105 New_Occurrence_Of
(Ret_Obj_Typ
, Loc
)));
5107 Insert_Before
(Ret_Obj_Decl
, Ptr_Type_Decl
);
5109 -- Create an access object that will be initialized to an
5110 -- access value denoting the return object, either coming
5111 -- from an implicit access value passed in by the caller
5112 -- or from the result of an allocator.
5114 Alloc_Obj_Id
:= Make_Temporary
(Loc
, 'R');
5115 Set_Etype
(Alloc_Obj_Id
, Ref_Type
);
5118 Make_Object_Declaration
(Loc
,
5119 Defining_Identifier
=> Alloc_Obj_Id
,
5120 Object_Definition
=>
5121 New_Occurrence_Of
(Ref_Type
, Loc
));
5123 Insert_Before
(Ret_Obj_Decl
, Alloc_Obj_Decl
);
5125 -- Create allocators for both the secondary stack and
5126 -- global heap. If there's an initialization expression,
5127 -- then create these as initialized allocators.
5129 if Present
(Ret_Obj_Expr
)
5130 and then not No_Initialization
(Ret_Obj_Decl
)
5132 -- Always use the type of the expression for the
5133 -- qualified expression, rather than the result type.
5134 -- In general we cannot always use the result type
5135 -- for the allocator, because the expression might be
5136 -- of a specific type, such as in the case of an
5137 -- aggregate or even a nonlimited object when the
5138 -- result type is a limited class-wide interface type.
5141 Make_Allocator
(Loc
,
5143 Make_Qualified_Expression
(Loc
,
5146 (Etype
(Ret_Obj_Expr
), Loc
),
5147 Expression
=> New_Copy_Tree
(Ret_Obj_Expr
)));
5150 -- If the function returns a class-wide type we cannot
5151 -- use the return type for the allocator. Instead we
5152 -- use the type of the expression, which must be an
5153 -- aggregate of a definite type.
5155 if Is_Class_Wide_Type
(Ret_Obj_Typ
) then
5157 Make_Allocator
(Loc
,
5160 (Etype
(Ret_Obj_Expr
), Loc
));
5163 Make_Allocator
(Loc
,
5165 New_Occurrence_Of
(Ret_Obj_Typ
, Loc
));
5168 -- If the object requires default initialization then
5169 -- that will happen later following the elaboration of
5170 -- the object renaming. If we don't turn it off here
5171 -- then the object will be default initialized twice.
5173 Set_No_Initialization
(Heap_Allocator
);
5176 -- Set the flag indicating that the allocator came from
5177 -- a build-in-place return statement, so we can avoid
5178 -- adjusting the allocated object. Note that this flag
5179 -- will be inherited by the copies made below.
5181 Set_Alloc_For_BIP_Return
(Heap_Allocator
);
5183 -- The Pool_Allocator is just like the Heap_Allocator,
5184 -- except we set Storage_Pool and Procedure_To_Call so
5185 -- it will use the user-defined storage pool.
5187 Pool_Allocator
:= New_Copy_Tree
(Heap_Allocator
);
5188 pragma Assert
(Alloc_For_BIP_Return
(Pool_Allocator
));
5190 -- Do not generate the renaming of the build-in-place
5191 -- pool parameter on ZFP because the parameter is not
5192 -- created in the first place.
5194 if RTE_Available
(RE_Root_Storage_Pool_Ptr
) then
5196 Make_Object_Renaming_Declaration
(Loc
,
5197 Defining_Identifier
=> Pool_Id
,
5200 (RTE
(RE_Root_Storage_Pool
), Loc
),
5202 Make_Explicit_Dereference
(Loc
,
5204 (Build_In_Place_Formal
5205 (Func_Id
, BIP_Storage_Pool
), Loc
)));
5206 Set_Storage_Pool
(Pool_Allocator
, Pool_Id
);
5207 Set_Procedure_To_Call
5208 (Pool_Allocator
, RTE
(RE_Allocate_Any
));
5210 Pool_Decl
:= Make_Null_Statement
(Loc
);
5213 -- If the No_Allocators restriction is active, then only
5214 -- an allocator for secondary stack allocation is needed.
5215 -- It's OK for such allocators to have Comes_From_Source
5216 -- set to False, because gigi knows not to flag them as
5217 -- being a violation of No_Implicit_Heap_Allocations.
5219 if Restriction_Active
(No_Allocators
) then
5220 SS_Allocator
:= Heap_Allocator
;
5221 Heap_Allocator
:= Make_Null
(Loc
);
5222 Pool_Allocator
:= Make_Null
(Loc
);
5224 -- Otherwise the heap and pool allocators may be needed,
5225 -- so we make another allocator for secondary stack
5229 SS_Allocator
:= New_Copy_Tree
(Heap_Allocator
);
5230 pragma Assert
(Alloc_For_BIP_Return
(SS_Allocator
));
5232 -- The heap and pool allocators are marked as
5233 -- Comes_From_Source since they correspond to an
5234 -- explicit user-written allocator (that is, it will
5235 -- only be executed on behalf of callers that call the
5236 -- function as initialization for such an allocator).
5237 -- Prevents errors when No_Implicit_Heap_Allocations
5240 Set_Comes_From_Source
(Heap_Allocator
, True);
5241 Set_Comes_From_Source
(Pool_Allocator
, True);
5244 -- The allocator is returned on the secondary stack.
5246 Set_Storage_Pool
(SS_Allocator
, RTE
(RE_SS_Pool
));
5247 Set_Procedure_To_Call
5248 (SS_Allocator
, RTE
(RE_SS_Allocate
));
5250 -- The allocator is returned on the secondary stack,
5251 -- so indicate that the function return, as well as
5252 -- all blocks that encloses the allocator, must not
5253 -- release it. The flags must be set now because
5254 -- the decision to use the secondary stack is done
5255 -- very late in the course of expanding the return
5256 -- statement, past the point where these flags are
5259 Set_Uses_Sec_Stack
(Func_Id
);
5260 Set_Uses_Sec_Stack
(Return_Statement_Entity
(N
));
5261 Set_Sec_Stack_Needed_For_Return
5262 (Return_Statement_Entity
(N
));
5263 Set_Enclosing_Sec_Stack_Return
(N
);
5265 -- Create an if statement to test the BIP_Alloc_Form
5266 -- formal and initialize the access object to either the
5267 -- BIP_Object_Access formal (BIP_Alloc_Form =
5268 -- Caller_Allocation), the result of allocating the
5269 -- object in the secondary stack (BIP_Alloc_Form =
5270 -- Secondary_Stack), or else an allocator to create the
5271 -- return object in the heap or user-defined pool
5272 -- (BIP_Alloc_Form = Global_Heap or User_Storage_Pool).
5274 -- ??? An unchecked type conversion must be made in the
5275 -- case of assigning the access object formal to the
5276 -- local access object, because a normal conversion would
5277 -- be illegal in some cases (such as converting access-
5278 -- to-unconstrained to access-to-constrained), but the
5279 -- the unchecked conversion will presumably fail to work
5280 -- right in just such cases. It's not clear at all how to
5284 Make_If_Statement
(Loc
,
5288 New_Occurrence_Of
(Obj_Alloc_Formal
, Loc
),
5290 Make_Integer_Literal
(Loc
,
5291 UI_From_Int
(BIP_Allocation_Form
'Pos
5292 (Caller_Allocation
)))),
5294 Then_Statements
=> New_List
(
5295 Make_Assignment_Statement
(Loc
,
5297 New_Occurrence_Of
(Alloc_Obj_Id
, Loc
),
5299 Make_Unchecked_Type_Conversion
(Loc
,
5301 New_Occurrence_Of
(Ref_Type
, Loc
),
5303 New_Occurrence_Of
(Obj_Acc_Formal
, Loc
)))),
5305 Elsif_Parts
=> New_List
(
5306 Make_Elsif_Part
(Loc
,
5310 New_Occurrence_Of
(Obj_Alloc_Formal
, Loc
),
5312 Make_Integer_Literal
(Loc
,
5313 UI_From_Int
(BIP_Allocation_Form
'Pos
5314 (Secondary_Stack
)))),
5316 Then_Statements
=> New_List
(
5317 Make_Assignment_Statement
(Loc
,
5319 New_Occurrence_Of
(Alloc_Obj_Id
, Loc
),
5320 Expression
=> SS_Allocator
))),
5322 Make_Elsif_Part
(Loc
,
5326 New_Occurrence_Of
(Obj_Alloc_Formal
, Loc
),
5328 Make_Integer_Literal
(Loc
,
5329 UI_From_Int
(BIP_Allocation_Form
'Pos
5332 Then_Statements
=> New_List
(
5333 Build_Heap_Allocator
5334 (Temp_Id
=> Alloc_Obj_Id
,
5335 Temp_Typ
=> Ref_Type
,
5337 Ret_Typ
=> Ret_Obj_Typ
,
5338 Alloc_Expr
=> Heap_Allocator
))),
5340 -- ???If all is well, we can put the following
5341 -- 'elsif' in the 'else', but this is a useful
5342 -- self-check in case caller and callee don't agree
5343 -- on whether BIPAlloc and so on should be passed.
5345 Make_Elsif_Part
(Loc
,
5349 New_Occurrence_Of
(Obj_Alloc_Formal
, Loc
),
5351 Make_Integer_Literal
(Loc
,
5352 UI_From_Int
(BIP_Allocation_Form
'Pos
5353 (User_Storage_Pool
)))),
5355 Then_Statements
=> New_List
(
5357 Build_Heap_Allocator
5358 (Temp_Id
=> Alloc_Obj_Id
,
5359 Temp_Typ
=> Ref_Type
,
5361 Ret_Typ
=> Ret_Obj_Typ
,
5362 Alloc_Expr
=> Pool_Allocator
)))),
5364 -- Raise Program_Error if it's none of the above;
5365 -- this is a compiler bug.
5367 Else_Statements
=> New_List
(
5368 Make_Raise_Program_Error
(Loc
,
5369 Reason
=> PE_Build_In_Place_Mismatch
)));
5371 -- If a separate initialization assignment was created
5372 -- earlier, append that following the assignment of the
5373 -- implicit access formal to the access object, to ensure
5374 -- that the return object is initialized in that case. In
5375 -- this situation, the target of the assignment must be
5376 -- rewritten to denote a dereference of the access to the
5377 -- return object passed in by the caller.
5379 if Present
(Init_Assignment
) then
5380 Rewrite
(Name
(Init_Assignment
),
5381 Make_Explicit_Dereference
(Loc
,
5382 Prefix
=> New_Occurrence_Of
(Alloc_Obj_Id
, Loc
)));
5385 (Original_Node
(Name
(Init_Assignment
))));
5386 Set_Assignment_OK
(Name
(Init_Assignment
));
5388 Set_Etype
(Name
(Init_Assignment
), Etype
(Ret_Obj_Id
));
5391 (Then_Statements
(Alloc_If_Stmt
), Init_Assignment
);
5394 Insert_Before
(Ret_Obj_Decl
, Alloc_If_Stmt
);
5396 -- Remember the local access object for use in the
5397 -- dereference of the renaming created below.
5399 Obj_Acc_Formal
:= Alloc_Obj_Id
;
5403 -- Replace the return object declaration with a renaming of a
5404 -- dereference of the access value designating the return
5408 Make_Explicit_Dereference
(Loc
,
5409 Prefix
=> New_Occurrence_Of
(Obj_Acc_Formal
, Loc
));
5411 Rewrite
(Ret_Obj_Decl
,
5412 Make_Object_Renaming_Declaration
(Loc
,
5413 Defining_Identifier
=> Ret_Obj_Id
,
5414 Access_Definition
=> Empty
,
5415 Subtype_Mark
=> New_Occurrence_Of
(Ret_Obj_Typ
, Loc
),
5416 Name
=> Obj_Acc_Deref
));
5418 Set_Renamed_Object
(Ret_Obj_Id
, Obj_Acc_Deref
);
5422 -- Case where we do not build a block
5425 -- We're about to drop Return_Object_Declarations on the floor, so
5426 -- we need to insert it, in case it got expanded into useful code.
5427 -- Remove side effects from expression, which may be duplicated in
5428 -- subsequent checks (see Expand_Simple_Function_Return).
5430 Insert_List_Before
(N
, Return_Object_Declarations
(N
));
5431 Remove_Side_Effects
(Exp
);
5433 -- Build simple_return_statement that returns the expression directly
5435 Return_Stmt
:= Make_Simple_Return_Statement
(Loc
, Expression
=> Exp
);
5436 Result
:= Return_Stmt
;
5439 -- Set the flag to prevent infinite recursion
5441 Set_Comes_From_Extended_Return_Statement
(Return_Stmt
);
5443 Rewrite
(N
, Result
);
5445 end Expand_N_Extended_Return_Statement
;
5447 ----------------------------
5448 -- Expand_N_Function_Call --
5449 ----------------------------
5451 procedure Expand_N_Function_Call
(N
: Node_Id
) is
5454 end Expand_N_Function_Call
;
5456 ---------------------------------------
5457 -- Expand_N_Procedure_Call_Statement --
5458 ---------------------------------------
5460 procedure Expand_N_Procedure_Call_Statement
(N
: Node_Id
) is
5463 end Expand_N_Procedure_Call_Statement
;
5465 --------------------------------------
5466 -- Expand_N_Simple_Return_Statement --
5467 --------------------------------------
5469 procedure Expand_N_Simple_Return_Statement
(N
: Node_Id
) is
5471 -- Defend against previous errors (i.e. the return statement calls a
5472 -- function that is not available in configurable runtime).
5474 if Present
(Expression
(N
))
5475 and then Nkind
(Expression
(N
)) = N_Empty
5477 Check_Error_Detected
;
5481 -- Distinguish the function and non-function cases:
5483 case Ekind
(Return_Applies_To
(Return_Statement_Entity
(N
))) is
5485 | E_Generic_Function
5487 Expand_Simple_Function_Return
(N
);
5491 | E_Generic_Procedure
5493 | E_Return_Statement
5495 Expand_Non_Function_Return
(N
);
5498 raise Program_Error
;
5502 when RE_Not_Available
=>
5504 end Expand_N_Simple_Return_Statement
;
5506 ------------------------------
5507 -- Expand_N_Subprogram_Body --
5508 ------------------------------
5510 -- Add poll call if ATC polling is enabled, unless the body will be inlined
5513 -- Add dummy push/pop label nodes at start and end to clear any local
5514 -- exception indications if local-exception-to-goto optimization is active.
5516 -- Add return statement if last statement in body is not a return statement
5517 -- (this makes things easier on Gigi which does not want to have to handle
5518 -- a missing return).
5520 -- Add call to Activate_Tasks if body is a task activator
5522 -- Deal with possible detection of infinite recursion
5524 -- Eliminate body completely if convention stubbed
5526 -- Encode entity names within body, since we will not need to reference
5527 -- these entities any longer in the front end.
5529 -- Initialize scalar out parameters if Initialize/Normalize_Scalars
5531 -- Reset Pure indication if any parameter has root type System.Address
5532 -- or has any parameters of limited types, where limited means that the
5533 -- run-time view is limited (i.e. the full type is limited).
5537 procedure Expand_N_Subprogram_Body
(N
: Node_Id
) is
5538 Body_Id
: constant Entity_Id
:= Defining_Entity
(N
);
5539 HSS
: constant Node_Id
:= Handled_Statement_Sequence
(N
);
5540 Loc
: constant Source_Ptr
:= Sloc
(N
);
5542 procedure Add_Return
(Spec_Id
: Entity_Id
; Stmts
: List_Id
);
5543 -- Append a return statement to the statement sequence Stmts if the last
5544 -- statement is not already a return or a goto statement. Note that the
5545 -- latter test is not critical, it does not matter if we add a few extra
5546 -- returns, since they get eliminated anyway later on. Spec_Id denotes
5547 -- the corresponding spec of the subprogram body.
5553 procedure Add_Return
(Spec_Id
: Entity_Id
; Stmts
: List_Id
) is
5554 Last_Stmt
: Node_Id
;
5559 -- Get last statement, ignoring any Pop_xxx_Label nodes, which are
5560 -- not relevant in this context since they are not executable.
5562 Last_Stmt
:= Last
(Stmts
);
5563 while Nkind
(Last_Stmt
) in N_Pop_xxx_Label
loop
5567 -- Now insert return unless last statement is a transfer
5569 if not Is_Transfer
(Last_Stmt
) then
5571 -- The source location for the return is the end label of the
5572 -- procedure if present. Otherwise use the sloc of the last
5573 -- statement in the list. If the list comes from a generated
5574 -- exception handler and we are not debugging generated code,
5575 -- all the statements within the handler are made invisible
5578 if Nkind
(Parent
(Stmts
)) = N_Exception_Handler
5579 and then not Comes_From_Source
(Parent
(Stmts
))
5581 Loc
:= Sloc
(Last_Stmt
);
5582 elsif Present
(End_Label
(HSS
)) then
5583 Loc
:= Sloc
(End_Label
(HSS
));
5585 Loc
:= Sloc
(Last_Stmt
);
5588 -- Append return statement, and set analyzed manually. We can't
5589 -- call Analyze on this return since the scope is wrong.
5591 -- Note: it almost works to push the scope and then do the Analyze
5592 -- call, but something goes wrong in some weird cases and it is
5593 -- not worth worrying about ???
5595 Stmt
:= Make_Simple_Return_Statement
(Loc
);
5597 -- The return statement is handled properly, and the call to the
5598 -- postcondition, inserted below, does not require information
5599 -- from the body either. However, that call is analyzed in the
5600 -- enclosing scope, and an elaboration check might improperly be
5601 -- added to it. A guard in Sem_Elab is needed to prevent that
5602 -- spurious check, see Check_Elab_Call.
5604 Append_To
(Stmts
, Stmt
);
5605 Set_Analyzed
(Stmt
);
5607 -- Call the _Postconditions procedure if the related subprogram
5608 -- has contract assertions that need to be verified on exit.
5610 if Ekind
(Spec_Id
) = E_Procedure
5611 and then Present
(Postconditions_Proc
(Spec_Id
))
5613 Insert_Action
(Stmt
,
5614 Make_Procedure_Call_Statement
(Loc
,
5616 New_Occurrence_Of
(Postconditions_Proc
(Spec_Id
), Loc
)));
5625 Spec_Id
: Entity_Id
;
5627 -- Start of processing for Expand_N_Subprogram_Body
5630 if Present
(Corresponding_Spec
(N
)) then
5631 Spec_Id
:= Corresponding_Spec
(N
);
5636 -- If this is a Pure function which has any parameters whose root type
5637 -- is System.Address, reset the Pure indication.
5638 -- This check is also performed when the subprogram is frozen, but we
5639 -- repeat it on the body so that the indication is consistent, and so
5640 -- it applies as well to bodies without separate specifications.
5642 if Is_Pure
(Spec_Id
)
5643 and then Is_Subprogram
(Spec_Id
)
5644 and then not Has_Pragma_Pure_Function
(Spec_Id
)
5646 Check_Function_With_Address_Parameter
(Spec_Id
);
5648 if Spec_Id
/= Body_Id
then
5649 Set_Is_Pure
(Body_Id
, Is_Pure
(Spec_Id
));
5653 -- Set L to either the list of declarations if present, or to the list
5654 -- of statements if no declarations are present. This is used to insert
5655 -- new stuff at the start.
5657 if Is_Non_Empty_List
(Declarations
(N
)) then
5658 L
:= Declarations
(N
);
5660 L
:= Statements
(HSS
);
5663 -- If local-exception-to-goto optimization active, insert dummy push
5664 -- statements at start, and dummy pop statements at end, but inhibit
5665 -- this if we have No_Exception_Handlers, since they are useless and
5666 -- intefere with analysis, e.g. by codepeer.
5668 if (Debug_Flag_Dot_G
5669 or else Restriction_Active
(No_Exception_Propagation
))
5670 and then not Restriction_Active
(No_Exception_Handlers
)
5671 and then not CodePeer_Mode
5672 and then Is_Non_Empty_List
(L
)
5675 FS
: constant Node_Id
:= First
(L
);
5676 FL
: constant Source_Ptr
:= Sloc
(FS
);
5681 -- LS points to either last statement, if statements are present
5682 -- or to the last declaration if there are no statements present.
5683 -- It is the node after which the pop's are generated.
5685 if Is_Non_Empty_List
(Statements
(HSS
)) then
5686 LS
:= Last
(Statements
(HSS
));
5693 Insert_List_Before_And_Analyze
(FS
, New_List
(
5694 Make_Push_Constraint_Error_Label
(FL
),
5695 Make_Push_Program_Error_Label
(FL
),
5696 Make_Push_Storage_Error_Label
(FL
)));
5698 Insert_List_After_And_Analyze
(LS
, New_List
(
5699 Make_Pop_Constraint_Error_Label
(LL
),
5700 Make_Pop_Program_Error_Label
(LL
),
5701 Make_Pop_Storage_Error_Label
(LL
)));
5705 -- Need poll on entry to subprogram if polling enabled. We only do this
5706 -- for non-empty subprograms, since it does not seem necessary to poll
5707 -- for a dummy null subprogram.
5709 if Is_Non_Empty_List
(L
) then
5711 -- Do not add a polling call if the subprogram is to be inlined by
5712 -- the back-end, to avoid repeated calls with multiple inlinings.
5714 if Is_Inlined
(Spec_Id
)
5715 and then Front_End_Inlining
5716 and then Optimization_Level
> 1
5720 Generate_Poll_Call
(First
(L
));
5724 -- Initialize any scalar OUT args if Initialize/Normalize_Scalars
5726 if Init_Or_Norm_Scalars
and then Is_Subprogram
(Spec_Id
) then
5732 -- Loop through formals
5734 F
:= First_Formal
(Spec_Id
);
5735 while Present
(F
) loop
5736 if Is_Scalar_Type
(Etype
(F
))
5737 and then Ekind
(F
) = E_Out_Parameter
5739 Check_Restriction
(No_Default_Initialization
, F
);
5741 -- Insert the initialization. We turn off validity checks
5742 -- for this assignment, since we do not want any check on
5743 -- the initial value itself (which may well be invalid).
5744 -- Predicate checks are disabled as well (RM 6.4.1 (13/3))
5747 Make_Assignment_Statement
(Loc
,
5748 Name
=> New_Occurrence_Of
(F
, Loc
),
5749 Expression
=> Get_Simple_Init_Val
(Etype
(F
), N
));
5750 Set_Suppress_Assignment_Checks
(A
);
5752 Insert_Before_And_Analyze
(First
(L
),
5753 A
, Suppress
=> Validity_Check
);
5761 -- Clear out statement list for stubbed procedure
5763 if Present
(Corresponding_Spec
(N
)) then
5764 Set_Elaboration_Flag
(N
, Spec_Id
);
5766 if Convention
(Spec_Id
) = Convention_Stubbed
5767 or else Is_Eliminated
(Spec_Id
)
5769 Set_Declarations
(N
, Empty_List
);
5770 Set_Handled_Statement_Sequence
(N
,
5771 Make_Handled_Sequence_Of_Statements
(Loc
,
5772 Statements
=> New_List
(Make_Null_Statement
(Loc
))));
5778 -- Create a set of discriminals for the next protected subprogram body
5780 if Is_List_Member
(N
)
5781 and then Present
(Parent
(List_Containing
(N
)))
5782 and then Nkind
(Parent
(List_Containing
(N
))) = N_Protected_Body
5783 and then Present
(Next_Protected_Operation
(N
))
5785 Set_Discriminals
(Parent
(Base_Type
(Scope
(Spec_Id
))));
5788 -- Returns_By_Ref flag is normally set when the subprogram is frozen but
5789 -- subprograms with no specs are not frozen.
5792 Typ
: constant Entity_Id
:= Etype
(Spec_Id
);
5793 Utyp
: constant Entity_Id
:= Underlying_Type
(Typ
);
5796 if Is_Limited_View
(Typ
) then
5797 Set_Returns_By_Ref
(Spec_Id
);
5799 elsif Present
(Utyp
) and then CW_Or_Has_Controlled_Part
(Utyp
) then
5800 Set_Returns_By_Ref
(Spec_Id
);
5804 -- For a procedure, we add a return for all possible syntactic ends of
5807 if Ekind_In
(Spec_Id
, E_Procedure
, E_Generic_Procedure
) then
5808 Add_Return
(Spec_Id
, Statements
(HSS
));
5810 if Present
(Exception_Handlers
(HSS
)) then
5811 Except_H
:= First_Non_Pragma
(Exception_Handlers
(HSS
));
5812 while Present
(Except_H
) loop
5813 Add_Return
(Spec_Id
, Statements
(Except_H
));
5814 Next_Non_Pragma
(Except_H
);
5818 -- For a function, we must deal with the case where there is at least
5819 -- one missing return. What we do is to wrap the entire body of the
5820 -- function in a block:
5833 -- raise Program_Error;
5836 -- This approach is necessary because the raise must be signalled to the
5837 -- caller, not handled by any local handler (RM 6.4(11)).
5839 -- Note: we do not need to analyze the constructed sequence here, since
5840 -- it has no handler, and an attempt to analyze the handled statement
5841 -- sequence twice is risky in various ways (e.g. the issue of expanding
5842 -- cleanup actions twice).
5844 elsif Has_Missing_Return
(Spec_Id
) then
5846 Hloc
: constant Source_Ptr
:= Sloc
(HSS
);
5847 Blok
: constant Node_Id
:=
5848 Make_Block_Statement
(Hloc
,
5849 Handled_Statement_Sequence
=> HSS
);
5850 Rais
: constant Node_Id
:=
5851 Make_Raise_Program_Error
(Hloc
,
5852 Reason
=> PE_Missing_Return
);
5855 Set_Handled_Statement_Sequence
(N
,
5856 Make_Handled_Sequence_Of_Statements
(Hloc
,
5857 Statements
=> New_List
(Blok
, Rais
)));
5859 Push_Scope
(Spec_Id
);
5866 -- If subprogram contains a parameterless recursive call, then we may
5867 -- have an infinite recursion, so see if we can generate code to check
5868 -- for this possibility if storage checks are not suppressed.
5870 if Ekind
(Spec_Id
) = E_Procedure
5871 and then Has_Recursive_Call
(Spec_Id
)
5872 and then not Storage_Checks_Suppressed
(Spec_Id
)
5874 Detect_Infinite_Recursion
(N
, Spec_Id
);
5877 -- Set to encode entity names in package body before gigi is called
5879 Qualify_Entity_Names
(N
);
5881 -- If the body belongs to a nonabstract library-level source primitive
5882 -- of a tagged type, install an elaboration check which ensures that a
5883 -- dispatching call targeting the primitive will not execute the body
5884 -- without it being previously elaborated.
5886 Install_Primitive_Elaboration_Check
(N
);
5887 end Expand_N_Subprogram_Body
;
5889 -----------------------------------
5890 -- Expand_N_Subprogram_Body_Stub --
5891 -----------------------------------
5893 procedure Expand_N_Subprogram_Body_Stub
(N
: Node_Id
) is
5897 if Present
(Corresponding_Body
(N
)) then
5898 Bod
:= Unit_Declaration_Node
(Corresponding_Body
(N
));
5900 -- The body may have been expanded already when it is analyzed
5901 -- through the subunit node. Do no expand again: it interferes
5902 -- with the construction of unnesting tables when generating C.
5904 if not Analyzed
(Bod
) then
5905 Expand_N_Subprogram_Body
(Bod
);
5908 -- Add full qualification to entities that may be created late
5909 -- during unnesting.
5911 Qualify_Entity_Names
(N
);
5913 end Expand_N_Subprogram_Body_Stub
;
5915 -------------------------------------
5916 -- Expand_N_Subprogram_Declaration --
5917 -------------------------------------
5919 -- If the declaration appears within a protected body, it is a private
5920 -- operation of the protected type. We must create the corresponding
5921 -- protected subprogram an associated formals. For a normal protected
5922 -- operation, this is done when expanding the protected type declaration.
5924 -- If the declaration is for a null procedure, emit null body
5926 procedure Expand_N_Subprogram_Declaration
(N
: Node_Id
) is
5927 Loc
: constant Source_Ptr
:= Sloc
(N
);
5928 Subp
: constant Entity_Id
:= Defining_Entity
(N
);
5932 Scop
: constant Entity_Id
:= Scope
(Subp
);
5934 Prot_Decl
: Node_Id
;
5935 Prot_Id
: Entity_Id
;
5937 -- Start of processing for Expand_N_Subprogram_Declaration
5940 -- In SPARK, subprogram declarations are only allowed in package
5943 if Nkind
(Parent
(N
)) /= N_Package_Specification
then
5944 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
5945 Check_SPARK_05_Restriction
5946 ("subprogram declaration is not a library item", N
);
5948 elsif Present
(Next
(N
))
5949 and then Nkind
(Next
(N
)) = N_Pragma
5950 and then Get_Pragma_Id
(Next
(N
)) = Pragma_Import
5952 -- In SPARK, subprogram declarations are also permitted in
5953 -- declarative parts when immediately followed by a corresponding
5954 -- pragma Import. We only check here that there is some pragma
5959 Check_SPARK_05_Restriction
5960 ("subprogram declaration is not allowed here", N
);
5964 -- Deal with case of protected subprogram. Do not generate protected
5965 -- operation if operation is flagged as eliminated.
5967 if Is_List_Member
(N
)
5968 and then Present
(Parent
(List_Containing
(N
)))
5969 and then Nkind
(Parent
(List_Containing
(N
))) = N_Protected_Body
5970 and then Is_Protected_Type
(Scop
)
5972 if No
(Protected_Body_Subprogram
(Subp
))
5973 and then not Is_Eliminated
(Subp
)
5976 Make_Subprogram_Declaration
(Loc
,
5978 Build_Protected_Sub_Specification
5979 (N
, Scop
, Unprotected_Mode
));
5981 -- The protected subprogram is declared outside of the protected
5982 -- body. Given that the body has frozen all entities so far, we
5983 -- analyze the subprogram and perform freezing actions explicitly.
5984 -- including the generation of an explicit freeze node, to ensure
5985 -- that gigi has the proper order of elaboration.
5986 -- If the body is a subunit, the insertion point is before the
5987 -- stub in the parent.
5989 Prot_Bod
:= Parent
(List_Containing
(N
));
5991 if Nkind
(Parent
(Prot_Bod
)) = N_Subunit
then
5992 Prot_Bod
:= Corresponding_Stub
(Parent
(Prot_Bod
));
5995 Insert_Before
(Prot_Bod
, Prot_Decl
);
5996 Prot_Id
:= Defining_Unit_Name
(Specification
(Prot_Decl
));
5997 Set_Has_Delayed_Freeze
(Prot_Id
);
5999 Push_Scope
(Scope
(Scop
));
6000 Analyze
(Prot_Decl
);
6001 Freeze_Before
(N
, Prot_Id
);
6002 Set_Protected_Body_Subprogram
(Subp
, Prot_Id
);
6004 -- Create protected operation as well. Even though the operation
6005 -- is only accessible within the body, it is possible to make it
6006 -- available outside of the protected object by using 'Access to
6007 -- provide a callback, so build protected version in all cases.
6010 Make_Subprogram_Declaration
(Loc
,
6012 Build_Protected_Sub_Specification
(N
, Scop
, Protected_Mode
));
6013 Insert_Before
(Prot_Bod
, Prot_Decl
);
6014 Analyze
(Prot_Decl
);
6019 -- Ada 2005 (AI-348): Generate body for a null procedure. In most
6020 -- cases this is superfluous because calls to it will be automatically
6021 -- inlined, but we definitely need the body if preconditions for the
6022 -- procedure are present, or if performing coverage analysis.
6024 elsif Nkind
(Specification
(N
)) = N_Procedure_Specification
6025 and then Null_Present
(Specification
(N
))
6028 Bod
: constant Node_Id
:= Body_To_Inline
(N
);
6031 Set_Has_Completion
(Subp
, False);
6032 Append_Freeze_Action
(Subp
, Bod
);
6034 -- The body now contains raise statements, so calls to it will
6037 Set_Is_Inlined
(Subp
, False);
6041 -- When generating C code, transform a function that returns a
6042 -- constrained array type into a procedure with an out parameter
6043 -- that carries the return value.
6045 -- We skip this transformation for unchecked conversions, since they
6046 -- are not needed by the C generator (and this also produces cleaner
6049 if Modify_Tree_For_C
6050 and then Nkind
(Specification
(N
)) = N_Function_Specification
6051 and then Is_Array_Type
(Etype
(Subp
))
6052 and then Is_Constrained
(Etype
(Subp
))
6053 and then not Is_Unchecked_Conversion_Instance
(Subp
)
6055 Build_Procedure_Form
(N
);
6057 end Expand_N_Subprogram_Declaration
;
6059 --------------------------------
6060 -- Expand_Non_Function_Return --
6061 --------------------------------
6063 procedure Expand_Non_Function_Return
(N
: Node_Id
) is
6064 pragma Assert
(No
(Expression
(N
)));
6066 Loc
: constant Source_Ptr
:= Sloc
(N
);
6067 Scope_Id
: Entity_Id
:= Return_Applies_To
(Return_Statement_Entity
(N
));
6068 Kind
: constant Entity_Kind
:= Ekind
(Scope_Id
);
6071 Goto_Stat
: Node_Id
;
6075 -- Call the _Postconditions procedure if the related subprogram has
6076 -- contract assertions that need to be verified on exit.
6078 if Ekind_In
(Scope_Id
, E_Entry
, E_Entry_Family
, E_Procedure
)
6079 and then Present
(Postconditions_Proc
(Scope_Id
))
6082 Make_Procedure_Call_Statement
(Loc
,
6083 Name
=> New_Occurrence_Of
(Postconditions_Proc
(Scope_Id
), Loc
)));
6086 -- If it is a return from a procedure do no extra steps
6088 if Kind
= E_Procedure
or else Kind
= E_Generic_Procedure
then
6091 -- If it is a nested return within an extended one, replace it with a
6092 -- return of the previously declared return object.
6094 elsif Kind
= E_Return_Statement
then
6096 Make_Simple_Return_Statement
(Loc
,
6098 New_Occurrence_Of
(First_Entity
(Scope_Id
), Loc
)));
6099 Set_Comes_From_Extended_Return_Statement
(N
);
6100 Set_Return_Statement_Entity
(N
, Scope_Id
);
6101 Expand_Simple_Function_Return
(N
);
6105 pragma Assert
(Is_Entry
(Scope_Id
));
6107 -- Look at the enclosing block to see whether the return is from an
6108 -- accept statement or an entry body.
6110 for J
in reverse 0 .. Scope_Stack
.Last
loop
6111 Scope_Id
:= Scope_Stack
.Table
(J
).Entity
;
6112 exit when Is_Concurrent_Type
(Scope_Id
);
6115 -- If it is a return from accept statement it is expanded as call to
6116 -- RTS Complete_Rendezvous and a goto to the end of the accept body.
6118 -- (cf : Expand_N_Accept_Statement, Expand_N_Selective_Accept,
6119 -- Expand_N_Accept_Alternative in exp_ch9.adb)
6121 if Is_Task_Type
(Scope_Id
) then
6124 Make_Procedure_Call_Statement
(Loc
,
6125 Name
=> New_Occurrence_Of
(RTE
(RE_Complete_Rendezvous
), Loc
));
6126 Insert_Before
(N
, Call
);
6127 -- why not insert actions here???
6130 Acc_Stat
:= Parent
(N
);
6131 while Nkind
(Acc_Stat
) /= N_Accept_Statement
loop
6132 Acc_Stat
:= Parent
(Acc_Stat
);
6135 Lab_Node
:= Last
(Statements
6136 (Handled_Statement_Sequence
(Acc_Stat
)));
6138 Goto_Stat
:= Make_Goto_Statement
(Loc
,
6139 Name
=> New_Occurrence_Of
6140 (Entity
(Identifier
(Lab_Node
)), Loc
));
6142 Set_Analyzed
(Goto_Stat
);
6144 Rewrite
(N
, Goto_Stat
);
6147 -- If it is a return from an entry body, put a Complete_Entry_Body call
6148 -- in front of the return.
6150 elsif Is_Protected_Type
(Scope_Id
) then
6152 Make_Procedure_Call_Statement
(Loc
,
6154 New_Occurrence_Of
(RTE
(RE_Complete_Entry_Body
), Loc
),
6155 Parameter_Associations
=> New_List
(
6156 Make_Attribute_Reference
(Loc
,
6159 (Find_Protection_Object
(Current_Scope
), Loc
),
6160 Attribute_Name
=> Name_Unchecked_Access
)));
6162 Insert_Before
(N
, Call
);
6165 end Expand_Non_Function_Return
;
6167 ---------------------------------------
6168 -- Expand_Protected_Object_Reference --
6169 ---------------------------------------
6171 function Expand_Protected_Object_Reference
6173 Scop
: Entity_Id
) return Node_Id
6175 Loc
: constant Source_Ptr
:= Sloc
(N
);
6182 Rec
:= Make_Identifier
(Loc
, Name_uObject
);
6183 Set_Etype
(Rec
, Corresponding_Record_Type
(Scop
));
6185 -- Find enclosing protected operation, and retrieve its first parameter,
6186 -- which denotes the enclosing protected object. If the enclosing
6187 -- operation is an entry, we are immediately within the protected body,
6188 -- and we can retrieve the object from the service entries procedure. A
6189 -- barrier function has the same signature as an entry. A barrier
6190 -- function is compiled within the protected object, but unlike
6191 -- protected operations its never needs locks, so that its protected
6192 -- body subprogram points to itself.
6194 Proc
:= Current_Scope
;
6195 while Present
(Proc
)
6196 and then Scope
(Proc
) /= Scop
6198 Proc
:= Scope
(Proc
);
6201 Corr
:= Protected_Body_Subprogram
(Proc
);
6205 -- Previous error left expansion incomplete.
6206 -- Nothing to do on this call.
6213 (First
(Parameter_Specifications
(Parent
(Corr
))));
6215 if Is_Subprogram
(Proc
) and then Proc
/= Corr
then
6217 -- Protected function or procedure
6219 Set_Entity
(Rec
, Param
);
6221 -- Rec is a reference to an entity which will not be in scope when
6222 -- the call is reanalyzed, and needs no further analysis.
6227 -- Entry or barrier function for entry body. The first parameter of
6228 -- the entry body procedure is pointer to the object. We create a
6229 -- local variable of the proper type, duplicating what is done to
6230 -- define _object later on.
6234 Obj_Ptr
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
6238 Make_Full_Type_Declaration
(Loc
,
6239 Defining_Identifier
=> Obj_Ptr
,
6241 Make_Access_To_Object_Definition
(Loc
,
6242 Subtype_Indication
=>
6244 (Corresponding_Record_Type
(Scop
), Loc
))));
6246 Insert_Actions
(N
, Decls
);
6247 Freeze_Before
(N
, Obj_Ptr
);
6250 Make_Explicit_Dereference
(Loc
,
6252 Unchecked_Convert_To
(Obj_Ptr
,
6253 New_Occurrence_Of
(Param
, Loc
)));
6255 -- Analyze new actual. Other actuals in calls are already analyzed
6256 -- and the list of actuals is not reanalyzed after rewriting.
6258 Set_Parent
(Rec
, N
);
6264 end Expand_Protected_Object_Reference
;
6266 --------------------------------------
6267 -- Expand_Protected_Subprogram_Call --
6268 --------------------------------------
6270 procedure Expand_Protected_Subprogram_Call
6277 procedure Expand_Internal_Init_Call
;
6278 -- A call to an operation of the type may occur in the initialization
6279 -- of a private component. In that case the prefix of the call is an
6280 -- entity name and the call is treated as internal even though it
6281 -- appears in code outside of the protected type.
6283 procedure Freeze_Called_Function
;
6284 -- If it is a function call it can appear in elaboration code and
6285 -- the called entity must be frozen before the call. This must be
6286 -- done before the call is expanded, as the expansion may rewrite it
6287 -- to something other than a call (e.g. a temporary initialized in a
6288 -- transient block).
6290 -------------------------------
6291 -- Expand_Internal_Init_Call --
6292 -------------------------------
6294 procedure Expand_Internal_Init_Call
is
6296 -- If the context is a protected object (rather than a protected
6297 -- type) the call itself is bound to raise program_error because
6298 -- the protected body will not have been elaborated yet. This is
6299 -- diagnosed subsequently in Sem_Elab.
6301 Freeze_Called_Function
;
6303 -- The target of the internal call is the first formal of the
6304 -- enclosing initialization procedure.
6306 Rec
:= New_Occurrence_Of
(First_Formal
(Current_Scope
), Sloc
(N
));
6307 Build_Protected_Subprogram_Call
(N
,
6312 Resolve
(N
, Etype
(Subp
));
6313 end Expand_Internal_Init_Call
;
6315 ----------------------------
6316 -- Freeze_Called_Function --
6317 ----------------------------
6319 procedure Freeze_Called_Function
is
6321 if Ekind
(Subp
) = E_Function
then
6322 Freeze_Expression
(Name
(N
));
6324 end Freeze_Called_Function
;
6326 -- Start of processing for Expand_Protected_Subprogram_Call
6329 -- If the protected object is not an enclosing scope, this is an inter-
6330 -- object function call. Inter-object procedure calls are expanded by
6331 -- Exp_Ch9.Build_Simple_Entry_Call. The call is intra-object only if the
6332 -- subprogram being called is in the protected body being compiled, and
6333 -- if the protected object in the call is statically the enclosing type.
6334 -- The object may be a component of some other data structure, in which
6335 -- case this must be handled as an inter-object call.
6337 if not In_Open_Scopes
(Scop
)
6338 or else Is_Entry_Wrapper
(Current_Scope
)
6339 or else not Is_Entity_Name
(Name
(N
))
6341 if Nkind
(Name
(N
)) = N_Selected_Component
then
6342 Rec
:= Prefix
(Name
(N
));
6344 elsif Nkind
(Name
(N
)) = N_Indexed_Component
then
6345 Rec
:= Prefix
(Prefix
(Name
(N
)));
6347 -- If this is a call within an entry wrapper, it appears within a
6348 -- precondition that calls another primitive of the synchronized
6349 -- type. The target object of the call is the first actual on the
6350 -- wrapper. Note that this is an external call, because the wrapper
6351 -- is called outside of the synchronized object. This means that
6352 -- an entry call to an entry with preconditions involves two
6353 -- synchronized operations.
6355 elsif Ekind
(Current_Scope
) = E_Procedure
6356 and then Is_Entry_Wrapper
(Current_Scope
)
6358 Rec
:= New_Occurrence_Of
(First_Entity
(Current_Scope
), Sloc
(N
));
6361 -- If the context is the initialization procedure for a protected
6362 -- type, the call is legal because the called entity must be a
6363 -- function of that enclosing type, and this is treated as an
6367 (Is_Entity_Name
(Name
(N
)) and then Inside_Init_Proc
);
6369 Expand_Internal_Init_Call
;
6373 Freeze_Called_Function
;
6374 Build_Protected_Subprogram_Call
(N
,
6375 Name
=> New_Occurrence_Of
(Subp
, Sloc
(N
)),
6376 Rec
=> Convert_Concurrent
(Rec
, Etype
(Rec
)),
6380 Rec
:= Expand_Protected_Object_Reference
(N
, Scop
);
6386 Freeze_Called_Function
;
6387 Build_Protected_Subprogram_Call
(N
,
6393 -- Analyze and resolve the new call. The actuals have already been
6394 -- resolved, but expansion of a function call will add extra actuals
6395 -- if needed. Analysis of a procedure call already includes resolution.
6399 if Ekind
(Subp
) = E_Function
then
6400 Resolve
(N
, Etype
(Subp
));
6402 end Expand_Protected_Subprogram_Call
;
6404 -----------------------------------
6405 -- Expand_Simple_Function_Return --
6406 -----------------------------------
6408 -- The "simple" comes from the syntax rule simple_return_statement. The
6409 -- semantics are not at all simple.
6411 procedure Expand_Simple_Function_Return
(N
: Node_Id
) is
6412 Loc
: constant Source_Ptr
:= Sloc
(N
);
6414 Scope_Id
: constant Entity_Id
:=
6415 Return_Applies_To
(Return_Statement_Entity
(N
));
6416 -- The function we are returning from
6418 R_Type
: constant Entity_Id
:= Etype
(Scope_Id
);
6419 -- The result type of the function
6421 Utyp
: constant Entity_Id
:= Underlying_Type
(R_Type
);
6423 Exp
: Node_Id
:= Expression
(N
);
6424 pragma Assert
(Present
(Exp
));
6426 Exptyp
: constant Entity_Id
:= Etype
(Exp
);
6427 -- The type of the expression (not necessarily the same as R_Type)
6429 Subtype_Ind
: Node_Id
;
6430 -- If the result type of the function is class-wide and the expression
6431 -- has a specific type, then we use the expression's type as the type of
6432 -- the return object. In cases where the expression is an aggregate that
6433 -- is built in place, this avoids the need for an expensive conversion
6434 -- of the return object to the specific type on assignments to the
6435 -- individual components.
6438 if Is_Class_Wide_Type
(R_Type
)
6439 and then not Is_Class_Wide_Type
(Exptyp
)
6440 and then Nkind
(Exp
) /= N_Type_Conversion
6442 Subtype_Ind
:= New_Occurrence_Of
(Exptyp
, Loc
);
6444 Subtype_Ind
:= New_Occurrence_Of
(R_Type
, Loc
);
6446 -- If the result type is class-wide and the expression is a view
6447 -- conversion, the conversion plays no role in the expansion because
6448 -- it does not modify the tag of the object. Remove the conversion
6449 -- altogether to prevent tag overwriting.
6451 if Is_Class_Wide_Type
(R_Type
)
6452 and then not Is_Class_Wide_Type
(Exptyp
)
6453 and then Nkind
(Exp
) = N_Type_Conversion
6455 Exp
:= Expression
(Exp
);
6459 -- Assert that if F says "return G(...);"
6460 -- then F and G are both b-i-p, or neither b-i-p.
6462 if Nkind
(Exp
) = N_Function_Call
then
6463 pragma Assert
(Ekind
(Scope_Id
) = E_Function
);
6465 (Is_Build_In_Place_Function
(Scope_Id
) =
6466 Is_Build_In_Place_Function_Call
(Exp
));
6470 -- For the case of a simple return that does not come from an
6471 -- extended return, in the case of build-in-place, we rewrite
6472 -- "return <expression>;" to be:
6474 -- return _anon_ : <return_subtype> := <expression>
6476 -- The expansion produced by Expand_N_Extended_Return_Statement will
6477 -- contain simple return statements (for example, a block containing
6478 -- simple return of the return object), which brings us back here with
6479 -- Comes_From_Extended_Return_Statement set. The reason for the barrier
6480 -- checking for a simple return that does not come from an extended
6481 -- return is to avoid this infinite recursion.
6483 -- The reason for this design is that for Ada 2005 limited returns, we
6484 -- need to reify the return object, so we can build it "in place", and
6485 -- we need a block statement to hang finalization and tasking stuff.
6487 -- ??? In order to avoid disruption, we avoid translating to extended
6488 -- return except in the cases where we really need to (Ada 2005 for
6489 -- inherently limited). We might prefer to do this translation in all
6490 -- cases (except perhaps for the case of Ada 95 inherently limited),
6491 -- in order to fully exercise the Expand_N_Extended_Return_Statement
6492 -- code. This would also allow us to do the build-in-place optimization
6493 -- for efficiency even in cases where it is semantically not required.
6495 -- As before, we check the type of the return expression rather than the
6496 -- return type of the function, because the latter may be a limited
6497 -- class-wide interface type, which is not a limited type, even though
6498 -- the type of the expression may be.
6501 (Comes_From_Extended_Return_Statement
(N
)
6502 or else not Is_Build_In_Place_Function_Call
(Exp
)
6503 or else Is_Build_In_Place_Function
(Scope_Id
));
6505 if not Comes_From_Extended_Return_Statement
(N
)
6506 and then Is_Build_In_Place_Function
(Scope_Id
)
6507 and then not Debug_Flag_Dot_L
6509 -- The functionality of interface thunks is simple and it is always
6510 -- handled by means of simple return statements. This leaves their
6511 -- expansion simple and clean.
6513 and then not Is_Thunk
(Current_Scope
)
6516 Return_Object_Entity
: constant Entity_Id
:=
6517 Make_Temporary
(Loc
, 'R', Exp
);
6519 Obj_Decl
: constant Node_Id
:=
6520 Make_Object_Declaration
(Loc
,
6521 Defining_Identifier
=> Return_Object_Entity
,
6522 Object_Definition
=> Subtype_Ind
,
6525 Ext
: constant Node_Id
:=
6526 Make_Extended_Return_Statement
(Loc
,
6527 Return_Object_Declarations
=> New_List
(Obj_Decl
));
6528 -- Do not perform this high-level optimization if the result type
6529 -- is an interface because the "this" pointer must be displaced.
6538 -- Here we have a simple return statement that is part of the expansion
6539 -- of an extended return statement (either written by the user, or
6540 -- generated by the above code).
6542 -- Always normalize C/Fortran boolean result. This is not always needed,
6543 -- but it seems a good idea to minimize the passing around of non-
6544 -- normalized values, and in any case this handles the processing of
6545 -- barrier functions for protected types, which turn the condition into
6546 -- a return statement.
6548 if Is_Boolean_Type
(Exptyp
)
6549 and then Nonzero_Is_True
(Exptyp
)
6551 Adjust_Condition
(Exp
);
6552 Adjust_Result_Type
(Exp
, Exptyp
);
6555 -- Do validity check if enabled for returns
6557 if Validity_Checks_On
6558 and then Validity_Check_Returns
6563 -- Check the result expression of a scalar function against the subtype
6564 -- of the function by inserting a conversion. This conversion must
6565 -- eventually be performed for other classes of types, but for now it's
6566 -- only done for scalars.
6569 if Is_Scalar_Type
(Exptyp
) then
6570 Rewrite
(Exp
, Convert_To
(R_Type
, Exp
));
6572 -- The expression is resolved to ensure that the conversion gets
6573 -- expanded to generate a possible constraint check.
6575 Analyze_And_Resolve
(Exp
, R_Type
);
6578 -- Deal with returning variable length objects and controlled types
6580 -- Nothing to do if we are returning by reference, or this is not a
6581 -- type that requires special processing (indicated by the fact that
6582 -- it requires a cleanup scope for the secondary stack case).
6584 if Is_Build_In_Place_Function
(Scope_Id
)
6585 or else Is_Limited_Interface
(Exptyp
)
6589 -- No copy needed for thunks returning interface type objects since
6590 -- the object is returned by reference and the maximum functionality
6591 -- required is just to displace the pointer.
6593 elsif Is_Thunk
(Current_Scope
) and then Is_Interface
(Exptyp
) then
6596 -- If the call is within a thunk and the type is a limited view, the
6597 -- backend will eventually see the non-limited view of the type.
6599 elsif Is_Thunk
(Current_Scope
) and then Is_Incomplete_Type
(Exptyp
) then
6602 elsif not Requires_Transient_Scope
(R_Type
) then
6604 -- Mutable records with variable-length components are not returned
6605 -- on the sec-stack, so we need to make sure that the back end will
6606 -- only copy back the size of the actual value, and not the maximum
6607 -- size. We create an actual subtype for this purpose. However we
6608 -- need not do it if the expression is a function call since this
6609 -- will be done in the called function and doing it here too would
6610 -- cause a temporary with maximum size to be created.
6613 Ubt
: constant Entity_Id
:= Underlying_Type
(Base_Type
(Exptyp
));
6617 if Nkind
(Exp
) /= N_Function_Call
6618 and then Has_Discriminants
(Ubt
)
6619 and then not Is_Constrained
(Ubt
)
6620 and then not Has_Unchecked_Union
(Ubt
)
6622 Decl
:= Build_Actual_Subtype
(Ubt
, Exp
);
6623 Ent
:= Defining_Identifier
(Decl
);
6624 Insert_Action
(Exp
, Decl
);
6625 Rewrite
(Exp
, Unchecked_Convert_To
(Ent
, Exp
));
6626 Analyze_And_Resolve
(Exp
);
6630 -- Here if secondary stack is used
6633 -- Prevent the reclamation of the secondary stack by all enclosing
6634 -- blocks and loops as well as the related function; otherwise the
6635 -- result would be reclaimed too early.
6637 Set_Enclosing_Sec_Stack_Return
(N
);
6639 -- Optimize the case where the result is a function call. In this
6640 -- case either the result is already on the secondary stack, or is
6641 -- already being returned with the stack pointer depressed and no
6642 -- further processing is required except to set the By_Ref flag
6643 -- to ensure that gigi does not attempt an extra unnecessary copy.
6644 -- (actually not just unnecessary but harmfully wrong in the case
6645 -- of a controlled type, where gigi does not know how to do a copy).
6646 -- To make up for a gcc 2.8.1 deficiency (???), we perform the copy
6647 -- for array types if the constrained status of the target type is
6648 -- different from that of the expression.
6650 if Requires_Transient_Scope
(Exptyp
)
6652 (not Is_Array_Type
(Exptyp
)
6653 or else Is_Constrained
(Exptyp
) = Is_Constrained
(R_Type
)
6654 or else CW_Or_Has_Controlled_Part
(Utyp
))
6655 and then Nkind
(Exp
) = N_Function_Call
6659 -- Remove side effects from the expression now so that other parts
6660 -- of the expander do not have to reanalyze this node without this
6663 Rewrite
(Exp
, Duplicate_Subexpr_No_Checks
(Exp
));
6665 -- Ada 2005 (AI-251): If the type of the returned object is
6666 -- an interface then add an implicit type conversion to force
6667 -- displacement of the "this" pointer.
6669 if Is_Interface
(R_Type
) then
6670 Rewrite
(Exp
, Convert_To
(R_Type
, Relocate_Node
(Exp
)));
6673 Analyze_And_Resolve
(Exp
, R_Type
);
6675 -- For controlled types, do the allocation on the secondary stack
6676 -- manually in order to call adjust at the right time:
6678 -- type Anon1 is access R_Type;
6679 -- for Anon1'Storage_pool use ss_pool;
6680 -- Anon2 : anon1 := new R_Type'(expr);
6681 -- return Anon2.all;
6683 -- We do the same for classwide types that are not potentially
6684 -- controlled (by the virtue of restriction No_Finalization) because
6685 -- gigi is not able to properly allocate class-wide types.
6687 elsif CW_Or_Has_Controlled_Part
(Utyp
) then
6689 Loc
: constant Source_Ptr
:= Sloc
(N
);
6690 Acc_Typ
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
6691 Alloc_Node
: Node_Id
;
6695 Set_Ekind
(Acc_Typ
, E_Access_Type
);
6697 Set_Associated_Storage_Pool
(Acc_Typ
, RTE
(RE_SS_Pool
));
6699 -- This is an allocator for the secondary stack, and it's fine
6700 -- to have Comes_From_Source set False on it, as gigi knows not
6701 -- to flag it as a violation of No_Implicit_Heap_Allocations.
6704 Make_Allocator
(Loc
,
6706 Make_Qualified_Expression
(Loc
,
6707 Subtype_Mark
=> New_Occurrence_Of
(Etype
(Exp
), Loc
),
6708 Expression
=> Relocate_Node
(Exp
)));
6710 -- We do not want discriminant checks on the declaration,
6711 -- given that it gets its value from the allocator.
6713 Set_No_Initialization
(Alloc_Node
);
6715 Temp
:= Make_Temporary
(Loc
, 'R', Alloc_Node
);
6717 Insert_List_Before_And_Analyze
(N
, New_List
(
6718 Make_Full_Type_Declaration
(Loc
,
6719 Defining_Identifier
=> Acc_Typ
,
6721 Make_Access_To_Object_Definition
(Loc
,
6722 Subtype_Indication
=> Subtype_Ind
)),
6724 Make_Object_Declaration
(Loc
,
6725 Defining_Identifier
=> Temp
,
6726 Object_Definition
=> New_Occurrence_Of
(Acc_Typ
, Loc
),
6727 Expression
=> Alloc_Node
)));
6730 Make_Explicit_Dereference
(Loc
,
6731 Prefix
=> New_Occurrence_Of
(Temp
, Loc
)));
6733 -- Ada 2005 (AI-251): If the type of the returned object is
6734 -- an interface then add an implicit type conversion to force
6735 -- displacement of the "this" pointer.
6737 if Is_Interface
(R_Type
) then
6738 Rewrite
(Exp
, Convert_To
(R_Type
, Relocate_Node
(Exp
)));
6741 Analyze_And_Resolve
(Exp
, R_Type
);
6744 -- Otherwise use the gigi mechanism to allocate result on the
6748 Check_Restriction
(No_Secondary_Stack
, N
);
6749 Set_Storage_Pool
(N
, RTE
(RE_SS_Pool
));
6750 Set_Procedure_To_Call
(N
, RTE
(RE_SS_Allocate
));
6754 -- Implement the rules of 6.5(8-10), which require a tag check in
6755 -- the case of a limited tagged return type, and tag reassignment for
6756 -- nonlimited tagged results. These actions are needed when the return
6757 -- type is a specific tagged type and the result expression is a
6758 -- conversion or a formal parameter, because in that case the tag of
6759 -- the expression might differ from the tag of the specific result type.
6761 if Is_Tagged_Type
(Utyp
)
6762 and then not Is_Class_Wide_Type
(Utyp
)
6763 and then (Nkind_In
(Exp
, N_Type_Conversion
,
6764 N_Unchecked_Type_Conversion
)
6765 or else (Is_Entity_Name
(Exp
)
6766 and then Ekind
(Entity
(Exp
)) in Formal_Kind
))
6768 -- When the return type is limited, perform a check that the tag of
6769 -- the result is the same as the tag of the return type.
6771 if Is_Limited_Type
(R_Type
) then
6773 Make_Raise_Constraint_Error
(Loc
,
6777 Make_Selected_Component
(Loc
,
6778 Prefix
=> Duplicate_Subexpr
(Exp
),
6779 Selector_Name
=> Make_Identifier
(Loc
, Name_uTag
)),
6781 Make_Attribute_Reference
(Loc
,
6783 New_Occurrence_Of
(Base_Type
(Utyp
), Loc
),
6784 Attribute_Name
=> Name_Tag
)),
6785 Reason
=> CE_Tag_Check_Failed
));
6787 -- If the result type is a specific nonlimited tagged type, then we
6788 -- have to ensure that the tag of the result is that of the result
6789 -- type. This is handled by making a copy of the expression in
6790 -- the case where it might have a different tag, namely when the
6791 -- expression is a conversion or a formal parameter. We create a new
6792 -- object of the result type and initialize it from the expression,
6793 -- which will implicitly force the tag to be set appropriately.
6797 ExpR
: constant Node_Id
:= Relocate_Node
(Exp
);
6798 Result_Id
: constant Entity_Id
:=
6799 Make_Temporary
(Loc
, 'R', ExpR
);
6800 Result_Exp
: constant Node_Id
:=
6801 New_Occurrence_Of
(Result_Id
, Loc
);
6802 Result_Obj
: constant Node_Id
:=
6803 Make_Object_Declaration
(Loc
,
6804 Defining_Identifier
=> Result_Id
,
6805 Object_Definition
=>
6806 New_Occurrence_Of
(R_Type
, Loc
),
6807 Constant_Present
=> True,
6808 Expression
=> ExpR
);
6811 Set_Assignment_OK
(Result_Obj
);
6812 Insert_Action
(Exp
, Result_Obj
);
6814 Rewrite
(Exp
, Result_Exp
);
6815 Analyze_And_Resolve
(Exp
, R_Type
);
6819 -- Ada 2005 (AI-344): If the result type is class-wide, then insert
6820 -- a check that the level of the return expression's underlying type
6821 -- is not deeper than the level of the master enclosing the function.
6822 -- Always generate the check when the type of the return expression
6823 -- is class-wide, when it's a type conversion, or when it's a formal
6824 -- parameter. Otherwise, suppress the check in the case where the
6825 -- return expression has a specific type whose level is known not to
6826 -- be statically deeper than the function's result type.
6828 -- No runtime check needed in interface thunks since it is performed
6829 -- by the target primitive associated with the thunk.
6831 -- Note: accessibility check is skipped in the VM case, since there
6832 -- does not seem to be any practical way to implement this check.
6834 elsif Ada_Version
>= Ada_2005
6835 and then Tagged_Type_Expansion
6836 and then Is_Class_Wide_Type
(R_Type
)
6837 and then not Is_Thunk
(Current_Scope
)
6838 and then not Scope_Suppress
.Suppress
(Accessibility_Check
)
6840 (Is_Class_Wide_Type
(Etype
(Exp
))
6841 or else Nkind_In
(Exp
, N_Type_Conversion
,
6842 N_Unchecked_Type_Conversion
)
6843 or else (Is_Entity_Name
(Exp
)
6844 and then Ekind
(Entity
(Exp
)) in Formal_Kind
)
6845 or else Scope_Depth
(Enclosing_Dynamic_Scope
(Etype
(Exp
))) >
6846 Scope_Depth
(Enclosing_Dynamic_Scope
(Scope_Id
)))
6852 -- Ada 2005 (AI-251): In class-wide interface objects we displace
6853 -- "this" to reference the base of the object. This is required to
6854 -- get access to the TSD of the object.
6856 if Is_Class_Wide_Type
(Etype
(Exp
))
6857 and then Is_Interface
(Etype
(Exp
))
6859 -- If the expression is an explicit dereference then we can
6860 -- directly displace the pointer to reference the base of
6863 if Nkind
(Exp
) = N_Explicit_Dereference
then
6865 Make_Explicit_Dereference
(Loc
,
6867 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
6868 Make_Function_Call
(Loc
,
6870 New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
6871 Parameter_Associations
=> New_List
(
6872 Unchecked_Convert_To
(RTE
(RE_Address
),
6873 Duplicate_Subexpr
(Prefix
(Exp
)))))));
6875 -- Similar case to the previous one but the expression is a
6876 -- renaming of an explicit dereference.
6878 elsif Nkind
(Exp
) = N_Identifier
6879 and then Present
(Renamed_Object
(Entity
(Exp
)))
6880 and then Nkind
(Renamed_Object
(Entity
(Exp
)))
6881 = N_Explicit_Dereference
6884 Make_Explicit_Dereference
(Loc
,
6886 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
6887 Make_Function_Call
(Loc
,
6889 New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
6890 Parameter_Associations
=> New_List
(
6891 Unchecked_Convert_To
(RTE
(RE_Address
),
6894 (Renamed_Object
(Entity
(Exp
)))))))));
6896 -- Common case: obtain the address of the actual object and
6897 -- displace the pointer to reference the base of the object.
6901 Make_Explicit_Dereference
(Loc
,
6903 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
6904 Make_Function_Call
(Loc
,
6906 New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
6907 Parameter_Associations
=> New_List
(
6908 Make_Attribute_Reference
(Loc
,
6909 Prefix
=> Duplicate_Subexpr
(Exp
),
6910 Attribute_Name
=> Name_Address
)))));
6914 Make_Attribute_Reference
(Loc
,
6915 Prefix
=> Duplicate_Subexpr
(Exp
),
6916 Attribute_Name
=> Name_Tag
);
6919 -- CodePeer does not do anything useful with
6920 -- Ada.Tags.Type_Specific_Data components.
6922 if not CodePeer_Mode
then
6924 Make_Raise_Program_Error
(Loc
,
6927 Left_Opnd
=> Build_Get_Access_Level
(Loc
, Tag_Node
),
6929 Make_Integer_Literal
(Loc
,
6930 Scope_Depth
(Enclosing_Dynamic_Scope
(Scope_Id
)))),
6931 Reason
=> PE_Accessibility_Check_Failed
));
6935 -- AI05-0073: If function has a controlling access result, check that
6936 -- the tag of the return value, if it is not null, matches designated
6937 -- type of return type.
6939 -- The return expression is referenced twice in the code below, so it
6940 -- must be made free of side effects. Given that different compilers
6941 -- may evaluate these parameters in different order, both occurrences
6944 elsif Ekind
(R_Type
) = E_Anonymous_Access_Type
6945 and then Has_Controlling_Result
(Scope_Id
)
6948 Make_Raise_Constraint_Error
(Loc
,
6953 Left_Opnd
=> Duplicate_Subexpr
(Exp
),
6954 Right_Opnd
=> Make_Null
(Loc
)),
6956 Right_Opnd
=> Make_Op_Ne
(Loc
,
6958 Make_Selected_Component
(Loc
,
6959 Prefix
=> Duplicate_Subexpr
(Exp
),
6960 Selector_Name
=> Make_Identifier
(Loc
, Name_uTag
)),
6963 Make_Attribute_Reference
(Loc
,
6965 New_Occurrence_Of
(Designated_Type
(R_Type
), Loc
),
6966 Attribute_Name
=> Name_Tag
))),
6968 Reason
=> CE_Tag_Check_Failed
),
6969 Suppress
=> All_Checks
);
6972 -- AI05-0234: RM 6.5(21/3). Check access discriminants to
6973 -- ensure that the function result does not outlive an
6974 -- object designated by one of it discriminants.
6976 if Present
(Extra_Accessibility_Of_Result
(Scope_Id
))
6977 and then Has_Unconstrained_Access_Discriminants
(R_Type
)
6980 Discrim_Source
: Node_Id
;
6982 procedure Check_Against_Result_Level
(Level
: Node_Id
);
6983 -- Check the given accessibility level against the level
6984 -- determined by the point of call. (AI05-0234).
6986 --------------------------------
6987 -- Check_Against_Result_Level --
6988 --------------------------------
6990 procedure Check_Against_Result_Level
(Level
: Node_Id
) is
6993 Make_Raise_Program_Error
(Loc
,
6999 (Extra_Accessibility_Of_Result
(Scope_Id
), Loc
)),
7000 Reason
=> PE_Accessibility_Check_Failed
));
7001 end Check_Against_Result_Level
;
7004 Discrim_Source
:= Exp
;
7005 while Nkind
(Discrim_Source
) = N_Qualified_Expression
loop
7006 Discrim_Source
:= Expression
(Discrim_Source
);
7009 if Nkind
(Discrim_Source
) = N_Identifier
7010 and then Is_Return_Object
(Entity
(Discrim_Source
))
7012 Discrim_Source
:= Entity
(Discrim_Source
);
7014 if Is_Constrained
(Etype
(Discrim_Source
)) then
7015 Discrim_Source
:= Etype
(Discrim_Source
);
7017 Discrim_Source
:= Expression
(Parent
(Discrim_Source
));
7020 elsif Nkind
(Discrim_Source
) = N_Identifier
7021 and then Nkind_In
(Original_Node
(Discrim_Source
),
7022 N_Aggregate
, N_Extension_Aggregate
)
7024 Discrim_Source
:= Original_Node
(Discrim_Source
);
7026 elsif Nkind
(Discrim_Source
) = N_Explicit_Dereference
and then
7027 Nkind
(Original_Node
(Discrim_Source
)) = N_Function_Call
7029 Discrim_Source
:= Original_Node
(Discrim_Source
);
7032 Discrim_Source
:= Unqual_Conv
(Discrim_Source
);
7034 case Nkind
(Discrim_Source
) is
7035 when N_Defining_Identifier
=>
7036 pragma Assert
(Is_Composite_Type
(Discrim_Source
)
7037 and then Has_Discriminants
(Discrim_Source
)
7038 and then Is_Constrained
(Discrim_Source
));
7041 Discrim
: Entity_Id
:=
7042 First_Discriminant
(Base_Type
(R_Type
));
7043 Disc_Elmt
: Elmt_Id
:=
7044 First_Elmt
(Discriminant_Constraint
7048 if Ekind
(Etype
(Discrim
)) =
7049 E_Anonymous_Access_Type
7051 Check_Against_Result_Level
7052 (Dynamic_Accessibility_Level
(Node
(Disc_Elmt
)));
7055 Next_Elmt
(Disc_Elmt
);
7056 Next_Discriminant
(Discrim
);
7057 exit when not Present
(Discrim
);
7062 | N_Extension_Aggregate
7064 -- Unimplemented: extension aggregate case where discrims
7065 -- come from ancestor part, not extension part.
7068 Discrim
: Entity_Id
:=
7069 First_Discriminant
(Base_Type
(R_Type
));
7071 Disc_Exp
: Node_Id
:= Empty
;
7073 Positionals_Exhausted
7074 : Boolean := not Present
(Expressions
7077 function Associated_Expr
7078 (Comp_Id
: Entity_Id
;
7079 Associations
: List_Id
) return Node_Id
;
7081 -- Given a component and a component associations list,
7082 -- locate the expression for that component; returns
7083 -- Empty if no such expression is found.
7085 ---------------------
7086 -- Associated_Expr --
7087 ---------------------
7089 function Associated_Expr
7090 (Comp_Id
: Entity_Id
;
7091 Associations
: List_Id
) return Node_Id
7097 -- Simple linear search seems ok here
7099 Assoc
:= First
(Associations
);
7100 while Present
(Assoc
) loop
7101 Choice
:= First
(Choices
(Assoc
));
7102 while Present
(Choice
) loop
7103 if (Nkind
(Choice
) = N_Identifier
7104 and then Chars
(Choice
) = Chars
(Comp_Id
))
7105 or else (Nkind
(Choice
) = N_Others_Choice
)
7107 return Expression
(Assoc
);
7117 end Associated_Expr
;
7120 if not Positionals_Exhausted
then
7121 Disc_Exp
:= First
(Expressions
(Discrim_Source
));
7125 if Positionals_Exhausted
then
7129 Component_Associations
(Discrim_Source
));
7132 if Ekind
(Etype
(Discrim
)) =
7133 E_Anonymous_Access_Type
7135 Check_Against_Result_Level
7136 (Dynamic_Accessibility_Level
(Disc_Exp
));
7139 Next_Discriminant
(Discrim
);
7140 exit when not Present
(Discrim
);
7142 if not Positionals_Exhausted
then
7144 Positionals_Exhausted
:= not Present
(Disc_Exp
);
7149 when N_Function_Call
=>
7151 -- No check needed (check performed by callee)
7157 Level
: constant Node_Id
:=
7158 Make_Integer_Literal
(Loc
,
7159 Object_Access_Level
(Discrim_Source
));
7162 -- Unimplemented: check for name prefix that includes
7163 -- a dereference of an access value with a dynamic
7164 -- accessibility level (e.g., an access param or a
7165 -- saooaaat) and use dynamic level in that case. For
7167 -- return Access_Param.all(Some_Index).Some_Component;
7170 Set_Etype
(Level
, Standard_Natural
);
7171 Check_Against_Result_Level
(Level
);
7177 -- If we are returning an object that may not be bit-aligned, then copy
7178 -- the value into a temporary first. This copy may need to expand to a
7179 -- loop of component operations.
7181 if Is_Possibly_Unaligned_Slice
(Exp
)
7182 or else Is_Possibly_Unaligned_Object
(Exp
)
7185 ExpR
: constant Node_Id
:= Relocate_Node
(Exp
);
7186 Tnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', ExpR
);
7189 Make_Object_Declaration
(Loc
,
7190 Defining_Identifier
=> Tnn
,
7191 Constant_Present
=> True,
7192 Object_Definition
=> New_Occurrence_Of
(R_Type
, Loc
),
7193 Expression
=> ExpR
),
7194 Suppress
=> All_Checks
);
7195 Rewrite
(Exp
, New_Occurrence_Of
(Tnn
, Loc
));
7199 -- Call the _Postconditions procedure if the related function has
7200 -- contract assertions that need to be verified on exit.
7202 if Ekind
(Scope_Id
) = E_Function
7203 and then Present
(Postconditions_Proc
(Scope_Id
))
7205 -- In the case of discriminated objects, we have created a
7206 -- constrained subtype above, and used the underlying type. This
7207 -- transformation is post-analysis and harmless, except that now the
7208 -- call to the post-condition will be analyzed and the type kinds
7211 if Nkind
(Exp
) = N_Unchecked_Type_Conversion
7212 and then Is_Private_Type
(R_Type
) /= Is_Private_Type
(Etype
(Exp
))
7214 Rewrite
(Exp
, Expression
(Relocate_Node
(Exp
)));
7217 -- We are going to reference the returned value twice in this case,
7218 -- once in the call to _Postconditions, and once in the actual return
7219 -- statement, but we can't have side effects happening twice.
7221 Force_Evaluation
(Exp
, Mode
=> Strict
);
7223 -- Generate call to _Postconditions
7226 Make_Procedure_Call_Statement
(Loc
,
7228 New_Occurrence_Of
(Postconditions_Proc
(Scope_Id
), Loc
),
7229 Parameter_Associations
=> New_List
(New_Copy_Tree
(Exp
))));
7232 -- Ada 2005 (AI-251): If this return statement corresponds with an
7233 -- simple return statement associated with an extended return statement
7234 -- and the type of the returned object is an interface then generate an
7235 -- implicit conversion to force displacement of the "this" pointer.
7237 if Ada_Version
>= Ada_2005
7238 and then Comes_From_Extended_Return_Statement
(N
)
7239 and then Nkind
(Expression
(N
)) = N_Identifier
7240 and then Is_Interface
(Utyp
)
7241 and then Utyp
/= Underlying_Type
(Exptyp
)
7243 Rewrite
(Exp
, Convert_To
(Utyp
, Relocate_Node
(Exp
)));
7244 Analyze_And_Resolve
(Exp
);
7246 end Expand_Simple_Function_Return
;
7248 --------------------------------------------
7249 -- Has_Unconstrained_Access_Discriminants --
7250 --------------------------------------------
7252 function Has_Unconstrained_Access_Discriminants
7253 (Subtyp
: Entity_Id
) return Boolean
7258 if Has_Discriminants
(Subtyp
)
7259 and then not Is_Constrained
(Subtyp
)
7261 Discr
:= First_Discriminant
(Subtyp
);
7262 while Present
(Discr
) loop
7263 if Ekind
(Etype
(Discr
)) = E_Anonymous_Access_Type
then
7267 Next_Discriminant
(Discr
);
7272 end Has_Unconstrained_Access_Discriminants
;
7274 -----------------------------------
7275 -- Is_Build_In_Place_Result_Type --
7276 -----------------------------------
7278 function Is_Build_In_Place_Result_Type
(Typ
: Entity_Id
) return Boolean is
7280 if not Expander_Active
then
7284 -- In Ada 2005 all functions with an inherently limited return type
7285 -- must be handled using a build-in-place profile, including the case
7286 -- of a function with a limited interface result, where the function
7287 -- may return objects of nonlimited descendants.
7289 if Is_Limited_View
(Typ
) then
7290 return Ada_Version
>= Ada_2005
and then not Debug_Flag_Dot_L
;
7293 if Debug_Flag_Dot_9
then
7297 if Has_Interfaces
(Typ
) then
7302 T
: Entity_Id
:= Typ
;
7304 -- For T'Class, return True if it's True for T. This is necessary
7305 -- because a class-wide function might say "return F (...)", where
7306 -- F returns the corresponding specific type. We need a loop in
7307 -- case T is a subtype of a class-wide type.
7309 while Is_Class_Wide_Type
(T
) loop
7313 -- If this is a generic formal type in an instance, return True if
7314 -- it's True for the generic actual type.
7316 if Nkind
(Parent
(T
)) = N_Subtype_Declaration
7317 and then Present
(Generic_Parent_Type
(Parent
(T
)))
7319 T
:= Entity
(Subtype_Indication
(Parent
(T
)));
7321 if Present
(Full_View
(T
)) then
7326 if Present
(Underlying_Type
(T
)) then
7327 T
:= Underlying_Type
(T
);
7332 -- So we can stop here in the debugger
7334 -- ???For now, enable build-in-place for a very narrow set of
7335 -- controlled types. Change "if True" to "if False" to
7336 -- experiment with more controlled types. Eventually, we might
7337 -- like to enable build-in-place for all tagged types, all
7338 -- types that need finalization, and all caller-unknown-size
7342 Result
:= Is_Controlled
(T
)
7343 and then Present
(Enclosing_Subprogram
(T
))
7344 and then not Is_Compilation_Unit
(Enclosing_Subprogram
(T
))
7345 and then Ekind
(Enclosing_Subprogram
(T
)) = E_Procedure
;
7347 Result
:= Is_Controlled
(T
);
7354 end Is_Build_In_Place_Result_Type
;
7356 --------------------------------
7357 -- Is_Build_In_Place_Function --
7358 --------------------------------
7360 function Is_Build_In_Place_Function
(E
: Entity_Id
) return Boolean is
7362 -- This function is called from Expand_Subtype_From_Expr during
7363 -- semantic analysis, even when expansion is off. In those cases
7364 -- the build_in_place expansion will not take place.
7366 if not Expander_Active
then
7370 -- For now we test whether E denotes a function or access-to-function
7371 -- type whose result subtype is inherently limited. Later this test
7372 -- may be revised to allow composite nonlimited types. Functions with
7373 -- a foreign convention or whose result type has a foreign convention
7376 if Ekind_In
(E
, E_Function
, E_Generic_Function
)
7377 or else (Ekind
(E
) = E_Subprogram_Type
7378 and then Etype
(E
) /= Standard_Void_Type
)
7380 -- Note: If the function has a foreign convention, it cannot build
7381 -- its result in place, so you're on your own. On the other hand,
7382 -- if only the return type has a foreign convention, its layout is
7383 -- intended to be compatible with the other language, but the build-
7384 -- in place machinery can ensure that the object is not copied.
7386 return Is_Build_In_Place_Result_Type
(Etype
(E
))
7387 and then not Has_Foreign_Convention
(E
)
7388 and then not Debug_Flag_Dot_L
;
7393 end Is_Build_In_Place_Function
;
7395 -------------------------------------
7396 -- Is_Build_In_Place_Function_Call --
7397 -------------------------------------
7399 function Is_Build_In_Place_Function_Call
(N
: Node_Id
) return Boolean is
7400 Exp_Node
: constant Node_Id
:= Unqual_Conv
(N
);
7401 Function_Id
: Entity_Id
;
7404 -- Return False if the expander is currently inactive, since awareness
7405 -- of build-in-place treatment is only relevant during expansion. Note
7406 -- that Is_Build_In_Place_Function, which is called as part of this
7407 -- function, is also conditioned this way, but we need to check here as
7408 -- well to avoid blowing up on processing protected calls when expansion
7409 -- is disabled (such as with -gnatc) since those would trip over the
7410 -- raise of Program_Error below.
7412 -- In SPARK mode, build-in-place calls are not expanded, so that we
7413 -- may end up with a call that is neither resolved to an entity, nor
7414 -- an indirect call.
7416 if not Expander_Active
or else Nkind
(Exp_Node
) /= N_Function_Call
then
7420 if Is_Entity_Name
(Name
(Exp_Node
)) then
7421 Function_Id
:= Entity
(Name
(Exp_Node
));
7423 -- In the case of an explicitly dereferenced call, use the subprogram
7424 -- type generated for the dereference.
7426 elsif Nkind
(Name
(Exp_Node
)) = N_Explicit_Dereference
then
7427 Function_Id
:= Etype
(Name
(Exp_Node
));
7429 -- This may be a call to a protected function.
7431 elsif Nkind
(Name
(Exp_Node
)) = N_Selected_Component
then
7432 Function_Id
:= Etype
(Entity
(Selector_Name
(Name
(Exp_Node
))));
7435 raise Program_Error
;
7439 Result
: constant Boolean := Is_Build_In_Place_Function
(Function_Id
);
7440 -- So we can stop here in the debugger
7444 end Is_Build_In_Place_Function_Call
;
7446 -----------------------
7447 -- Freeze_Subprogram --
7448 -----------------------
7450 procedure Freeze_Subprogram
(N
: Node_Id
) is
7451 Loc
: constant Source_Ptr
:= Sloc
(N
);
7453 procedure Register_Predefined_DT_Entry
(Prim
: Entity_Id
);
7454 -- (Ada 2005): Register a predefined primitive in all the secondary
7455 -- dispatch tables of its primitive type.
7457 ----------------------------------
7458 -- Register_Predefined_DT_Entry --
7459 ----------------------------------
7461 procedure Register_Predefined_DT_Entry
(Prim
: Entity_Id
) is
7462 Iface_DT_Ptr
: Elmt_Id
;
7463 Tagged_Typ
: Entity_Id
;
7464 Thunk_Id
: Entity_Id
;
7465 Thunk_Code
: Node_Id
;
7468 Tagged_Typ
:= Find_Dispatching_Type
(Prim
);
7470 if No
(Access_Disp_Table
(Tagged_Typ
))
7471 or else not Has_Interfaces
(Tagged_Typ
)
7472 or else not RTE_Available
(RE_Interface_Tag
)
7473 or else Restriction_Active
(No_Dispatching_Calls
)
7478 -- Skip the first two access-to-dispatch-table pointers since they
7479 -- leads to the primary dispatch table (predefined DT and user
7480 -- defined DT). We are only concerned with the secondary dispatch
7481 -- table pointers. Note that the access-to- dispatch-table pointer
7482 -- corresponds to the first implemented interface retrieved below.
7485 Next_Elmt
(Next_Elmt
(First_Elmt
(Access_Disp_Table
(Tagged_Typ
))));
7487 while Present
(Iface_DT_Ptr
)
7488 and then Ekind
(Node
(Iface_DT_Ptr
)) = E_Constant
7490 pragma Assert
(Has_Thunks
(Node
(Iface_DT_Ptr
)));
7491 Expand_Interface_Thunk
(Prim
, Thunk_Id
, Thunk_Code
);
7493 if Present
(Thunk_Code
) then
7494 Insert_Actions_After
(N
, New_List
(
7497 Build_Set_Predefined_Prim_Op_Address
(Loc
,
7499 New_Occurrence_Of
(Node
(Next_Elmt
(Iface_DT_Ptr
)), Loc
),
7500 Position
=> DT_Position
(Prim
),
7502 Unchecked_Convert_To
(RTE
(RE_Prim_Ptr
),
7503 Make_Attribute_Reference
(Loc
,
7504 Prefix
=> New_Occurrence_Of
(Thunk_Id
, Loc
),
7505 Attribute_Name
=> Name_Unrestricted_Access
))),
7507 Build_Set_Predefined_Prim_Op_Address
(Loc
,
7510 (Node
(Next_Elmt
(Next_Elmt
(Next_Elmt
(Iface_DT_Ptr
)))),
7512 Position
=> DT_Position
(Prim
),
7514 Unchecked_Convert_To
(RTE
(RE_Prim_Ptr
),
7515 Make_Attribute_Reference
(Loc
,
7516 Prefix
=> New_Occurrence_Of
(Prim
, Loc
),
7517 Attribute_Name
=> Name_Unrestricted_Access
)))));
7520 -- Skip the tag of the predefined primitives dispatch table
7522 Next_Elmt
(Iface_DT_Ptr
);
7523 pragma Assert
(Has_Thunks
(Node
(Iface_DT_Ptr
)));
7525 -- Skip tag of the no-thunks dispatch table
7527 Next_Elmt
(Iface_DT_Ptr
);
7528 pragma Assert
(not Has_Thunks
(Node
(Iface_DT_Ptr
)));
7530 -- Skip tag of predefined primitives no-thunks dispatch table
7532 Next_Elmt
(Iface_DT_Ptr
);
7533 pragma Assert
(not Has_Thunks
(Node
(Iface_DT_Ptr
)));
7535 Next_Elmt
(Iface_DT_Ptr
);
7537 end Register_Predefined_DT_Entry
;
7541 Subp
: constant Entity_Id
:= Entity
(N
);
7543 -- Start of processing for Freeze_Subprogram
7546 -- We suppress the initialization of the dispatch table entry when
7547 -- not Tagged_Type_Expansion because the dispatching mechanism is
7548 -- handled internally by the target.
7550 if Is_Dispatching_Operation
(Subp
)
7551 and then not Is_Abstract_Subprogram
(Subp
)
7552 and then Present
(DTC_Entity
(Subp
))
7553 and then Present
(Scope
(DTC_Entity
(Subp
)))
7554 and then Tagged_Type_Expansion
7555 and then not Restriction_Active
(No_Dispatching_Calls
)
7556 and then RTE_Available
(RE_Tag
)
7559 Typ
: constant Entity_Id
:= Scope
(DTC_Entity
(Subp
));
7562 -- Handle private overridden primitives
7564 if not Is_CPP_Class
(Typ
) then
7565 Check_Overriding_Operation
(Subp
);
7568 -- We assume that imported CPP primitives correspond with objects
7569 -- whose constructor is in the CPP side; therefore we don't need
7570 -- to generate code to register them in the dispatch table.
7572 if Is_CPP_Class
(Typ
) then
7575 -- Handle CPP primitives found in derivations of CPP_Class types.
7576 -- These primitives must have been inherited from some parent, and
7577 -- there is no need to register them in the dispatch table because
7578 -- Build_Inherit_Prims takes care of initializing these slots.
7580 elsif Is_Imported
(Subp
)
7581 and then (Convention
(Subp
) = Convention_CPP
7582 or else Convention
(Subp
) = Convention_C
)
7586 -- Generate code to register the primitive in non statically
7587 -- allocated dispatch tables
7589 elsif not Building_Static_DT
(Scope
(DTC_Entity
(Subp
))) then
7591 -- When a primitive is frozen, enter its name in its dispatch
7594 if not Is_Interface
(Typ
)
7595 or else Present
(Interface_Alias
(Subp
))
7597 if Is_Predefined_Dispatching_Operation
(Subp
) then
7598 Register_Predefined_DT_Entry
(Subp
);
7601 Insert_Actions_After
(N
,
7602 Register_Primitive
(Loc
, Prim
=> Subp
));
7608 -- Mark functions that return by reference. Note that it cannot be part
7609 -- of the normal semantic analysis of the spec since the underlying
7610 -- returned type may not be known yet (for private types).
7613 Typ
: constant Entity_Id
:= Etype
(Subp
);
7614 Utyp
: constant Entity_Id
:= Underlying_Type
(Typ
);
7617 if Is_Limited_View
(Typ
) then
7618 Set_Returns_By_Ref
(Subp
);
7620 elsif Present
(Utyp
) and then CW_Or_Has_Controlled_Part
(Utyp
) then
7621 Set_Returns_By_Ref
(Subp
);
7625 -- Wnen freezing a null procedure, analyze its delayed aspects now
7626 -- because we may not have reached the end of the declarative list when
7627 -- delayed aspects are normally analyzed. This ensures that dispatching
7628 -- calls are properly rewritten when the generated _Postcondition
7629 -- procedure is analyzed in the null procedure body.
7631 if Nkind
(Parent
(Subp
)) = N_Procedure_Specification
7632 and then Null_Present
(Parent
(Subp
))
7634 Analyze_Entry_Or_Subprogram_Contract
(Subp
);
7636 end Freeze_Subprogram
;
7638 ------------------------------
7639 -- Insert_Post_Call_Actions --
7640 ------------------------------
7642 procedure Insert_Post_Call_Actions
(N
: Node_Id
; Post_Call
: List_Id
) is
7643 Context
: constant Node_Id
:= Parent
(N
);
7646 if Is_Empty_List
(Post_Call
) then
7650 -- Cases where the call is not a member of a statement list. This
7651 -- includes the case where the call is an actual in another function
7652 -- call or indexing, i.e. an expression context as well.
7654 if not Is_List_Member
(N
)
7655 or else Nkind_In
(Context
, N_Function_Call
, N_Indexed_Component
)
7657 -- In Ada 2012 the call may be a function call in an expression
7658 -- (since OUT and IN OUT parameters are now allowed for such calls).
7659 -- The write-back of (in)-out parameters is handled by the back-end,
7660 -- but the constraint checks generated when subtypes of formal and
7661 -- actual don't match must be inserted in the form of assignments.
7663 if Nkind
(Original_Node
(N
)) = N_Function_Call
then
7664 pragma Assert
(Ada_Version
>= Ada_2012
);
7665 -- Functions with '[in] out' parameters are only allowed in Ada
7668 -- We used to handle this by climbing up parents to a
7669 -- non-statement/declaration and then simply making a call to
7670 -- Insert_Actions_After (P, Post_Call), but that doesn't work
7671 -- for Ada 2012. If we are in the middle of an expression, e.g.
7672 -- the condition of an IF, this call would insert after the IF
7673 -- statement, which is much too late to be doing the write back.
7676 -- if Clobber (X) then
7677 -- Put_Line (X'Img);
7682 -- Now assume Clobber changes X, if we put the write back after
7683 -- the IF, the Put_Line gets the wrong value and the goto causes
7684 -- the write back to be skipped completely.
7686 -- To deal with this, we replace the call by
7689 -- Tnnn : constant function-result-type := function-call;
7690 -- Post_Call actions
7696 Loc
: constant Source_Ptr
:= Sloc
(N
);
7697 Tnnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
7698 FRTyp
: constant Entity_Id
:= Etype
(N
);
7699 Name
: constant Node_Id
:= Relocate_Node
(N
);
7702 Prepend_To
(Post_Call
,
7703 Make_Object_Declaration
(Loc
,
7704 Defining_Identifier
=> Tnnn
,
7705 Object_Definition
=> New_Occurrence_Of
(FRTyp
, Loc
),
7706 Constant_Present
=> True,
7707 Expression
=> Name
));
7710 Make_Expression_With_Actions
(Loc
,
7711 Actions
=> Post_Call
,
7712 Expression
=> New_Occurrence_Of
(Tnnn
, Loc
)));
7714 -- We don't want to just blindly call Analyze_And_Resolve
7715 -- because that would cause unwanted recursion on the call.
7716 -- So for a moment set the call as analyzed to prevent that
7717 -- recursion, and get the rest analyzed properly, then reset
7718 -- the analyzed flag, so our caller can continue.
7720 Set_Analyzed
(Name
, True);
7721 Analyze_And_Resolve
(N
, FRTyp
);
7722 Set_Analyzed
(Name
, False);
7725 -- If not the special Ada 2012 case of a function call, then we must
7726 -- have the triggering statement of a triggering alternative or an
7727 -- entry call alternative, and we can add the post call stuff to the
7728 -- corresponding statement list.
7731 pragma Assert
(Nkind_In
(Context
, N_Entry_Call_Alternative
,
7732 N_Triggering_Alternative
));
7734 if Is_Non_Empty_List
(Statements
(Context
)) then
7735 Insert_List_Before_And_Analyze
7736 (First
(Statements
(Context
)), Post_Call
);
7738 Set_Statements
(Context
, Post_Call
);
7742 -- A procedure call is always part of a declarative or statement list,
7743 -- however a function call may appear nested within a construct. Most
7744 -- cases of function call nesting are handled in the special case above.
7745 -- The only exception is when the function call acts as an actual in a
7746 -- procedure call. In this case the function call is in a list, but the
7747 -- post-call actions must be inserted after the procedure call.
7749 elsif Nkind
(Context
) = N_Procedure_Call_Statement
then
7750 Insert_Actions_After
(Context
, Post_Call
);
7752 -- Otherwise, normal case where N is in a statement sequence, just put
7753 -- the post-call stuff after the call statement.
7756 Insert_Actions_After
(N
, Post_Call
);
7758 end Insert_Post_Call_Actions
;
7760 -----------------------
7761 -- Is_Null_Procedure --
7762 -----------------------
7764 function Is_Null_Procedure
(Subp
: Entity_Id
) return Boolean is
7765 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
7768 if Ekind
(Subp
) /= E_Procedure
then
7771 -- Check if this is a declared null procedure
7773 elsif Nkind
(Decl
) = N_Subprogram_Declaration
then
7774 if not Null_Present
(Specification
(Decl
)) then
7777 elsif No
(Body_To_Inline
(Decl
)) then
7780 -- Check if the body contains only a null statement, followed by
7781 -- the return statement added during expansion.
7785 Orig_Bod
: constant Node_Id
:= Body_To_Inline
(Decl
);
7791 if Nkind
(Orig_Bod
) /= N_Subprogram_Body
then
7794 -- We must skip SCIL nodes because they are currently
7795 -- implemented as special N_Null_Statement nodes.
7799 (Statements
(Handled_Statement_Sequence
(Orig_Bod
)));
7800 Stat2
:= Next_Non_SCIL_Node
(Stat
);
7803 Is_Empty_List
(Declarations
(Orig_Bod
))
7804 and then Nkind
(Stat
) = N_Null_Statement
7808 (Nkind
(Stat2
) = N_Simple_Return_Statement
7809 and then No
(Next
(Stat2
))));
7817 end Is_Null_Procedure
;
7819 -------------------------------------------
7820 -- Make_Build_In_Place_Call_In_Allocator --
7821 -------------------------------------------
7823 procedure Make_Build_In_Place_Call_In_Allocator
7824 (Allocator
: Node_Id
;
7825 Function_Call
: Node_Id
)
7827 Acc_Type
: constant Entity_Id
:= Etype
(Allocator
);
7828 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
7829 Func_Call
: Node_Id
:= Function_Call
;
7830 Ref_Func_Call
: Node_Id
;
7831 Function_Id
: Entity_Id
;
7832 Result_Subt
: Entity_Id
;
7833 New_Allocator
: Node_Id
;
7834 Return_Obj_Access
: Entity_Id
; -- temp for function result
7835 Temp_Init
: Node_Id
; -- initial value of Return_Obj_Access
7836 Alloc_Form
: BIP_Allocation_Form
;
7837 Pool
: Node_Id
; -- nonnull if Alloc_Form = User_Storage_Pool
7838 Return_Obj_Actual
: Node_Id
; -- the temp.all, in caller-allocates case
7839 Chain
: Entity_Id
; -- activation chain, in case of tasks
7842 -- Step past qualification or unchecked conversion (the latter can occur
7843 -- in cases of calls to 'Input).
7845 if Nkind_In
(Func_Call
,
7846 N_Qualified_Expression
,
7848 N_Unchecked_Type_Conversion
)
7850 Func_Call
:= Expression
(Func_Call
);
7853 -- Mark the call as processed as a build-in-place call
7855 pragma Assert
(not Is_Expanded_Build_In_Place_Call
(Func_Call
));
7856 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
7858 if Is_Entity_Name
(Name
(Func_Call
)) then
7859 Function_Id
:= Entity
(Name
(Func_Call
));
7861 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
7862 Function_Id
:= Etype
(Name
(Func_Call
));
7865 raise Program_Error
;
7868 Result_Subt
:= Available_View
(Etype
(Function_Id
));
7870 -- Create a temp for the function result. In the caller-allocates case,
7871 -- this will be initialized to the result of a new uninitialized
7872 -- allocator. Note: we do not use Allocator as the Related_Node of
7873 -- Return_Obj_Access in call to Make_Temporary below as this would
7874 -- create a sort of infinite "recursion".
7876 Return_Obj_Access
:= Make_Temporary
(Loc
, 'R');
7877 Set_Etype
(Return_Obj_Access
, Acc_Type
);
7878 Set_Can_Never_Be_Null
(Acc_Type
, False);
7879 -- It gets initialized to null, so we can't have that
7881 -- When the result subtype is constrained, the return object is
7882 -- allocated on the caller side, and access to it is passed to the
7885 -- Here and in related routines, we must examine the full view of the
7886 -- type, because the view at the point of call may differ from that
7887 -- that in the function body, and the expansion mechanism depends on
7888 -- the characteristics of the full view.
7890 if Is_Constrained
(Underlying_Type
(Result_Subt
)) then
7891 -- Replace the initialized allocator of form "new T'(Func (...))"
7892 -- with an uninitialized allocator of form "new T", where T is the
7893 -- result subtype of the called function. The call to the function
7894 -- is handled separately further below.
7897 Make_Allocator
(Loc
,
7898 Expression
=> New_Occurrence_Of
(Result_Subt
, Loc
));
7899 Set_No_Initialization
(New_Allocator
);
7901 -- Copy attributes to new allocator. Note that the new allocator
7902 -- logically comes from source if the original one did, so copy the
7903 -- relevant flag. This ensures proper treatment of the restriction
7904 -- No_Implicit_Heap_Allocations in this case.
7906 Set_Storage_Pool
(New_Allocator
, Storage_Pool
(Allocator
));
7907 Set_Procedure_To_Call
(New_Allocator
, Procedure_To_Call
(Allocator
));
7908 Set_Comes_From_Source
(New_Allocator
, Comes_From_Source
(Allocator
));
7910 Rewrite
(Allocator
, New_Allocator
);
7912 -- Initial value of the temp is the result of the uninitialized
7913 -- allocator. Unchecked_Convert is needed for T'Input where T is
7914 -- derived from a controlled type.
7916 Temp_Init
:= Relocate_Node
(Allocator
);
7919 (Function_Call
, N_Type_Conversion
, N_Unchecked_Type_Conversion
)
7921 Temp_Init
:= Unchecked_Convert_To
(Acc_Type
, Temp_Init
);
7924 -- Indicate that caller allocates, and pass in the return object
7926 Alloc_Form
:= Caller_Allocation
;
7927 Pool
:= Make_Null
(No_Location
);
7928 Return_Obj_Actual
:=
7929 Make_Unchecked_Type_Conversion
(Loc
,
7930 Subtype_Mark
=> New_Occurrence_Of
(Result_Subt
, Loc
),
7932 Make_Explicit_Dereference
(Loc
,
7933 Prefix
=> New_Occurrence_Of
(Return_Obj_Access
, Loc
)));
7935 -- When the result subtype is unconstrained, the function itself must
7936 -- perform the allocation of the return object, so we pass parameters
7942 -- Case of a user-defined storage pool. Pass an allocation parameter
7943 -- indicating that the function should allocate its result in the
7944 -- pool, and pass the pool. Use 'Unrestricted_Access because the
7945 -- pool may not be aliased.
7947 if Present
(Associated_Storage_Pool
(Acc_Type
)) then
7948 Alloc_Form
:= User_Storage_Pool
;
7950 Make_Attribute_Reference
(Loc
,
7953 (Associated_Storage_Pool
(Acc_Type
), Loc
),
7954 Attribute_Name
=> Name_Unrestricted_Access
);
7956 -- No user-defined pool; pass an allocation parameter indicating that
7957 -- the function should allocate its result on the heap.
7960 Alloc_Form
:= Global_Heap
;
7961 Pool
:= Make_Null
(No_Location
);
7964 -- The caller does not provide the return object in this case, so we
7965 -- have to pass null for the object access actual.
7967 Return_Obj_Actual
:= Empty
;
7970 -- Declare the temp object
7972 Insert_Action
(Allocator
,
7973 Make_Object_Declaration
(Loc
,
7974 Defining_Identifier
=> Return_Obj_Access
,
7975 Object_Definition
=> New_Occurrence_Of
(Acc_Type
, Loc
),
7976 Expression
=> Temp_Init
));
7978 Ref_Func_Call
:= Make_Reference
(Loc
, Func_Call
);
7980 -- Ada 2005 (AI-251): If the type of the allocator is an interface
7981 -- then generate an implicit conversion to force displacement of the
7984 if Is_Interface
(Designated_Type
(Acc_Type
)) then
7987 OK_Convert_To
(Acc_Type
, Ref_Func_Call
));
7989 -- If the types are incompatible, we need an unchecked conversion. Note
7990 -- that the full types will be compatible, but the types not visibly
7994 (Function_Call
, N_Type_Conversion
, N_Unchecked_Type_Conversion
)
7996 Ref_Func_Call
:= Unchecked_Convert_To
(Acc_Type
, Ref_Func_Call
);
8000 Assign
: constant Node_Id
:=
8001 Make_Assignment_Statement
(Loc
,
8002 Name
=> New_Occurrence_Of
(Return_Obj_Access
, Loc
),
8003 Expression
=> Ref_Func_Call
);
8004 -- Assign the result of the function call into the temp. In the
8005 -- caller-allocates case, this is overwriting the temp with its
8006 -- initial value, which has no effect. In the callee-allocates case,
8007 -- this is setting the temp to point to the object allocated by the
8008 -- callee. Unchecked_Convert is needed for T'Input where T is derived
8009 -- from a controlled type.
8012 -- Actions to be inserted. If there are no tasks, this is just the
8013 -- assignment statement. If the allocated object has tasks, we need
8014 -- to wrap the assignment in a block that activates them. The
8015 -- activation chain of that block must be passed to the function,
8016 -- rather than some outer chain.
8018 if Has_Task
(Result_Subt
) then
8019 Actions
:= New_List
;
8020 Build_Task_Allocate_Block_With_Init_Stmts
8021 (Actions
, Allocator
, Init_Stmts
=> New_List
(Assign
));
8022 Chain
:= Activation_Chain_Entity
(Last
(Actions
));
8024 Actions
:= New_List
(Assign
);
8028 Insert_Actions
(Allocator
, Actions
);
8031 -- When the function has a controlling result, an allocation-form
8032 -- parameter must be passed indicating that the caller is allocating
8033 -- the result object. This is needed because such a function can be
8034 -- called as a dispatching operation and must be treated similarly
8035 -- to functions with unconstrained result subtypes.
8037 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8038 (Func_Call
, Function_Id
, Alloc_Form
, Pool_Actual
=> Pool
);
8040 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8041 (Func_Call
, Function_Id
, Acc_Type
);
8043 Add_Task_Actuals_To_Build_In_Place_Call
8044 (Func_Call
, Function_Id
, Master_Actual
=> Master_Id
(Acc_Type
),
8047 -- Add an implicit actual to the function call that provides access
8048 -- to the allocated object. An unchecked conversion to the (specific)
8049 -- result subtype of the function is inserted to handle cases where
8050 -- the access type of the allocator has a class-wide designated type.
8052 Add_Access_Actual_To_Build_In_Place_Call
8053 (Func_Call
, Function_Id
, Return_Obj_Actual
);
8055 -- Finally, replace the allocator node with a reference to the temp
8057 Rewrite
(Allocator
, New_Occurrence_Of
(Return_Obj_Access
, Loc
));
8059 Analyze_And_Resolve
(Allocator
, Acc_Type
);
8060 end Make_Build_In_Place_Call_In_Allocator
;
8062 ---------------------------------------------------
8063 -- Make_Build_In_Place_Call_In_Anonymous_Context --
8064 ---------------------------------------------------
8066 procedure Make_Build_In_Place_Call_In_Anonymous_Context
8067 (Function_Call
: Node_Id
)
8069 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8070 Func_Call
: constant Node_Id
:= Unqual_Conv
(Function_Call
);
8071 Function_Id
: Entity_Id
;
8072 Result_Subt
: Entity_Id
;
8073 Return_Obj_Id
: Entity_Id
;
8074 Return_Obj_Decl
: Entity_Id
;
8077 -- If the call has already been processed to add build-in-place actuals
8078 -- then return. One place this can occur is for calls to build-in-place
8079 -- functions that occur within a call to a protected operation, where
8080 -- due to rewriting and expansion of the protected call there can be
8081 -- more than one call to Expand_Actuals for the same set of actuals.
8083 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8087 -- Mark the call as processed as a build-in-place call
8089 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8091 if Is_Entity_Name
(Name
(Func_Call
)) then
8092 Function_Id
:= Entity
(Name
(Func_Call
));
8094 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8095 Function_Id
:= Etype
(Name
(Func_Call
));
8098 raise Program_Error
;
8101 Result_Subt
:= Etype
(Function_Id
);
8103 -- If the build-in-place function returns a controlled object, then the
8104 -- object needs to be finalized immediately after the context. Since
8105 -- this case produces a transient scope, the servicing finalizer needs
8106 -- to name the returned object. Create a temporary which is initialized
8107 -- with the function call:
8109 -- Temp_Id : Func_Type := BIP_Func_Call;
8111 -- The initialization expression of the temporary will be rewritten by
8112 -- the expander using the appropriate mechanism in Make_Build_In_Place_
8113 -- Call_In_Object_Declaration.
8115 if Needs_Finalization
(Result_Subt
) then
8117 Temp_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'R');
8118 Temp_Decl
: Node_Id
;
8121 -- Reset the guard on the function call since the following does
8122 -- not perform actual call expansion.
8124 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
, False);
8127 Make_Object_Declaration
(Loc
,
8128 Defining_Identifier
=> Temp_Id
,
8129 Object_Definition
=>
8130 New_Occurrence_Of
(Result_Subt
, Loc
),
8132 New_Copy_Tree
(Function_Call
));
8134 Insert_Action
(Function_Call
, Temp_Decl
);
8136 Rewrite
(Function_Call
, New_Occurrence_Of
(Temp_Id
, Loc
));
8137 Analyze
(Function_Call
);
8140 -- When the result subtype is definite, an object of the subtype is
8141 -- declared and an access value designating it is passed as an actual.
8143 elsif Caller_Known_Size
(Func_Call
, Result_Subt
) then
8145 -- Create a temporary object to hold the function result
8147 Return_Obj_Id
:= Make_Temporary
(Loc
, 'R');
8148 Set_Etype
(Return_Obj_Id
, Result_Subt
);
8151 Make_Object_Declaration
(Loc
,
8152 Defining_Identifier
=> Return_Obj_Id
,
8153 Aliased_Present
=> True,
8154 Object_Definition
=> New_Occurrence_Of
(Result_Subt
, Loc
));
8156 Set_No_Initialization
(Return_Obj_Decl
);
8158 Insert_Action
(Func_Call
, Return_Obj_Decl
);
8160 -- When the function has a controlling result, an allocation-form
8161 -- parameter must be passed indicating that the caller is allocating
8162 -- the result object. This is needed because such a function can be
8163 -- called as a dispatching operation and must be treated similarly
8164 -- to functions with unconstrained result subtypes.
8166 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8167 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8169 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8170 (Func_Call
, Function_Id
);
8172 Add_Task_Actuals_To_Build_In_Place_Call
8173 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8175 -- Add an implicit actual to the function call that provides access
8176 -- to the caller's return object.
8178 Add_Access_Actual_To_Build_In_Place_Call
8179 (Func_Call
, Function_Id
, New_Occurrence_Of
(Return_Obj_Id
, Loc
));
8181 -- When the result subtype is unconstrained, the function must allocate
8182 -- the return object in the secondary stack, so appropriate implicit
8183 -- parameters are added to the call to indicate that. A transient
8184 -- scope is established to ensure eventual cleanup of the result.
8187 -- Pass an allocation parameter indicating that the function should
8188 -- allocate its result on the secondary stack.
8190 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8191 (Func_Call
, Function_Id
, Alloc_Form
=> Secondary_Stack
);
8193 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8194 (Func_Call
, Function_Id
);
8196 Add_Task_Actuals_To_Build_In_Place_Call
8197 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8199 -- Pass a null value to the function since no return object is
8200 -- available on the caller side.
8202 Add_Access_Actual_To_Build_In_Place_Call
8203 (Func_Call
, Function_Id
, Empty
);
8205 end Make_Build_In_Place_Call_In_Anonymous_Context
;
8207 --------------------------------------------
8208 -- Make_Build_In_Place_Call_In_Assignment --
8209 --------------------------------------------
8211 procedure Make_Build_In_Place_Call_In_Assignment
8213 Function_Call
: Node_Id
)
8215 Func_Call
: constant Node_Id
:= Unqual_Conv
(Function_Call
);
8216 Lhs
: constant Node_Id
:= Name
(Assign
);
8217 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8218 Func_Id
: Entity_Id
;
8221 Ptr_Typ
: Entity_Id
;
8222 Ptr_Typ_Decl
: Node_Id
;
8224 Result_Subt
: Entity_Id
;
8227 -- Mark the call as processed as a build-in-place call
8229 pragma Assert
(not Is_Expanded_Build_In_Place_Call
(Func_Call
));
8230 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8232 if Is_Entity_Name
(Name
(Func_Call
)) then
8233 Func_Id
:= Entity
(Name
(Func_Call
));
8235 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8236 Func_Id
:= Etype
(Name
(Func_Call
));
8239 raise Program_Error
;
8242 Result_Subt
:= Etype
(Func_Id
);
8244 -- When the result subtype is unconstrained, an additional actual must
8245 -- be passed to indicate that the caller is providing the return object.
8246 -- This parameter must also be passed when the called function has a
8247 -- controlling result, because dispatching calls to the function needs
8248 -- to be treated effectively the same as calls to class-wide functions.
8250 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8251 (Func_Call
, Func_Id
, Alloc_Form
=> Caller_Allocation
);
8253 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8254 (Func_Call
, Func_Id
);
8256 Add_Task_Actuals_To_Build_In_Place_Call
8257 (Func_Call
, Func_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8259 -- Add an implicit actual to the function call that provides access to
8260 -- the caller's return object.
8262 Add_Access_Actual_To_Build_In_Place_Call
8265 Make_Unchecked_Type_Conversion
(Loc
,
8266 Subtype_Mark
=> New_Occurrence_Of
(Result_Subt
, Loc
),
8267 Expression
=> Relocate_Node
(Lhs
)));
8269 -- Create an access type designating the function's result subtype
8271 Ptr_Typ
:= Make_Temporary
(Loc
, 'A');
8274 Make_Full_Type_Declaration
(Loc
,
8275 Defining_Identifier
=> Ptr_Typ
,
8277 Make_Access_To_Object_Definition
(Loc
,
8278 All_Present
=> True,
8279 Subtype_Indication
=>
8280 New_Occurrence_Of
(Result_Subt
, Loc
)));
8281 Insert_After_And_Analyze
(Assign
, Ptr_Typ_Decl
);
8283 -- Finally, create an access object initialized to a reference to the
8284 -- function call. We know this access value is non-null, so mark the
8285 -- entity accordingly to suppress junk access checks.
8287 New_Expr
:= Make_Reference
(Loc
, Relocate_Node
(Func_Call
));
8289 -- Add a conversion if it's the wrong type
8291 if Etype
(New_Expr
) /= Ptr_Typ
then
8293 Make_Unchecked_Type_Conversion
(Loc
,
8294 New_Occurrence_Of
(Ptr_Typ
, Loc
), New_Expr
);
8297 Obj_Id
:= Make_Temporary
(Loc
, 'R', New_Expr
);
8298 Set_Etype
(Obj_Id
, Ptr_Typ
);
8299 Set_Is_Known_Non_Null
(Obj_Id
);
8302 Make_Object_Declaration
(Loc
,
8303 Defining_Identifier
=> Obj_Id
,
8304 Object_Definition
=> New_Occurrence_Of
(Ptr_Typ
, Loc
),
8305 Expression
=> New_Expr
);
8306 Insert_After_And_Analyze
(Ptr_Typ_Decl
, Obj_Decl
);
8308 Rewrite
(Assign
, Make_Null_Statement
(Loc
));
8309 end Make_Build_In_Place_Call_In_Assignment
;
8311 ----------------------------------------------------
8312 -- Make_Build_In_Place_Call_In_Object_Declaration --
8313 ----------------------------------------------------
8315 procedure Make_Build_In_Place_Call_In_Object_Declaration
8316 (Obj_Decl
: Node_Id
;
8317 Function_Call
: Node_Id
)
8319 function Get_Function_Id
(Func_Call
: Node_Id
) return Entity_Id
;
8320 -- Get the value of Function_Id, below
8322 ---------------------
8323 -- Get_Function_Id --
8324 ---------------------
8326 function Get_Function_Id
(Func_Call
: Node_Id
) return Entity_Id
is
8328 if Is_Entity_Name
(Name
(Func_Call
)) then
8329 return Entity
(Name
(Func_Call
));
8331 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8332 return Etype
(Name
(Func_Call
));
8335 raise Program_Error
;
8337 end Get_Function_Id
;
8341 Func_Call
: constant Node_Id
:= Unqual_Conv
(Function_Call
);
8342 Function_Id
: constant Entity_Id
:= Get_Function_Id
(Func_Call
);
8343 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8344 Obj_Loc
: constant Source_Ptr
:= Sloc
(Obj_Decl
);
8345 Obj_Def_Id
: constant Entity_Id
:= Defining_Identifier
(Obj_Decl
);
8346 Obj_Typ
: constant Entity_Id
:= Etype
(Obj_Def_Id
);
8347 Encl_Func
: constant Entity_Id
:= Enclosing_Subprogram
(Obj_Def_Id
);
8348 Result_Subt
: constant Entity_Id
:= Etype
(Function_Id
);
8350 Call_Deref
: Node_Id
;
8351 Caller_Object
: Node_Id
;
8353 Designated_Type
: Entity_Id
;
8354 Fmaster_Actual
: Node_Id
:= Empty
;
8355 Pool_Actual
: Node_Id
;
8356 Ptr_Typ
: Entity_Id
;
8357 Ptr_Typ_Decl
: Node_Id
;
8358 Pass_Caller_Acc
: Boolean := False;
8361 Definite
: constant Boolean :=
8362 Caller_Known_Size
(Func_Call
, Result_Subt
)
8363 and then not Is_Class_Wide_Type
(Obj_Typ
);
8364 -- In the case of "X : T'Class := F(...);", where F returns a
8365 -- Caller_Known_Size (specific) tagged type, we treat it as
8366 -- indefinite, because the code for the Definite case below sets the
8367 -- initialization expression of the object to Empty, which would be
8368 -- illegal Ada, and would cause gigi to misallocate X.
8370 -- Start of processing for Make_Build_In_Place_Call_In_Object_Declaration
8373 -- If the call has already been processed to add build-in-place actuals
8376 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8380 -- Mark the call as processed as a build-in-place call
8382 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8384 -- Create an access type designating the function's result subtype.
8385 -- We use the type of the original call because it may be a call to an
8386 -- inherited operation, which the expansion has replaced with the parent
8387 -- operation that yields the parent type. Note that this access type
8388 -- must be declared before we establish a transient scope, so that it
8389 -- receives the proper accessibility level.
8391 if Is_Class_Wide_Type
(Obj_Typ
)
8392 and then not Is_Interface
(Obj_Typ
)
8393 and then not Is_Class_Wide_Type
(Etype
(Function_Call
))
8395 Designated_Type
:= Obj_Typ
;
8397 Designated_Type
:= Etype
(Function_Call
);
8400 Ptr_Typ
:= Make_Temporary
(Loc
, 'A');
8402 Make_Full_Type_Declaration
(Loc
,
8403 Defining_Identifier
=> Ptr_Typ
,
8405 Make_Access_To_Object_Definition
(Loc
,
8406 All_Present
=> True,
8407 Subtype_Indication
=>
8408 New_Occurrence_Of
(Designated_Type
, Loc
)));
8410 -- The access type and its accompanying object must be inserted after
8411 -- the object declaration in the constrained case, so that the function
8412 -- call can be passed access to the object. In the indefinite case, or
8413 -- if the object declaration is for a return object, the access type and
8414 -- object must be inserted before the object, since the object
8415 -- declaration is rewritten to be a renaming of a dereference of the
8416 -- access object. Note: we need to freeze Ptr_Typ explicitly, because
8417 -- the result object is in a different (transient) scope, so won't cause
8420 if Definite
and then not Is_Return_Object
(Obj_Def_Id
) then
8421 Insert_After_And_Analyze
(Obj_Decl
, Ptr_Typ_Decl
);
8423 Insert_Action
(Obj_Decl
, Ptr_Typ_Decl
);
8426 -- Force immediate freezing of Ptr_Typ because Res_Decl will be
8427 -- elaborated in an inner (transient) scope and thus won't cause
8428 -- freezing by itself. It's not an itype, but it needs to be frozen
8429 -- inside the current subprogram (see Freeze_Outside in freeze.adb).
8431 Freeze_Itype
(Ptr_Typ
, Ptr_Typ_Decl
);
8433 -- If the object is a return object of an enclosing build-in-place
8434 -- function, then the implicit build-in-place parameters of the
8435 -- enclosing function are simply passed along to the called function.
8436 -- (Unfortunately, this won't cover the case of extension aggregates
8437 -- where the ancestor part is a build-in-place indefinite function
8438 -- call that should be passed along the caller's parameters.
8439 -- Currently those get mishandled by reassigning the result of the
8440 -- call to the aggregate return object, when the call result should
8441 -- really be directly built in place in the aggregate and not in a
8444 if Is_Return_Object
(Obj_Def_Id
) then
8445 Pass_Caller_Acc
:= True;
8447 -- When the enclosing function has a BIP_Alloc_Form formal then we
8448 -- pass it along to the callee (such as when the enclosing function
8449 -- has an unconstrained or tagged result type).
8451 if Needs_BIP_Alloc_Form
(Encl_Func
) then
8452 if RTE_Available
(RE_Root_Storage_Pool_Ptr
) then
8455 (Build_In_Place_Formal
8456 (Encl_Func
, BIP_Storage_Pool
), Loc
);
8458 -- The build-in-place pool formal is not built on e.g. ZFP
8461 Pool_Actual
:= Empty
;
8464 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8465 (Function_Call
=> Func_Call
,
8466 Function_Id
=> Function_Id
,
8469 (Build_In_Place_Formal
(Encl_Func
, BIP_Alloc_Form
), Loc
),
8470 Pool_Actual
=> Pool_Actual
);
8472 -- Otherwise, if enclosing function has a definite result subtype,
8473 -- then caller allocation will be used.
8476 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8477 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8480 if Needs_BIP_Finalization_Master
(Encl_Func
) then
8483 (Build_In_Place_Formal
8484 (Encl_Func
, BIP_Finalization_Master
), Loc
);
8487 -- Retrieve the BIPacc formal from the enclosing function and convert
8488 -- it to the access type of the callee's BIP_Object_Access formal.
8491 Make_Unchecked_Type_Conversion
(Loc
,
8494 (Etype
(Build_In_Place_Formal
8495 (Function_Id
, BIP_Object_Access
)),
8499 (Build_In_Place_Formal
(Encl_Func
, BIP_Object_Access
),
8502 -- In the definite case, add an implicit actual to the function call
8503 -- that provides access to the declared object. An unchecked conversion
8504 -- to the (specific) result type of the function is inserted to handle
8505 -- the case where the object is declared with a class-wide type.
8509 Make_Unchecked_Type_Conversion
(Loc
,
8510 Subtype_Mark
=> New_Occurrence_Of
(Result_Subt
, Loc
),
8511 Expression
=> New_Occurrence_Of
(Obj_Def_Id
, Loc
));
8513 -- When the function has a controlling result, an allocation-form
8514 -- parameter must be passed indicating that the caller is allocating
8515 -- the result object. This is needed because such a function can be
8516 -- called as a dispatching operation and must be treated similarly to
8517 -- functions with indefinite result subtypes.
8519 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8520 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8522 -- The allocation for indefinite library-level objects occurs on the
8523 -- heap as opposed to the secondary stack. This accommodates DLLs where
8524 -- the secondary stack is destroyed after each library unload. This is a
8525 -- hybrid mechanism where a stack-allocated object lives on the heap.
8527 elsif Is_Library_Level_Entity
(Obj_Def_Id
)
8528 and then not Restriction_Active
(No_Implicit_Heap_Allocations
)
8530 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8531 (Func_Call
, Function_Id
, Alloc_Form
=> Global_Heap
);
8532 Caller_Object
:= Empty
;
8534 -- Create a finalization master for the access result type to ensure
8535 -- that the heap allocation can properly chain the object and later
8536 -- finalize it when the library unit goes out of scope.
8538 if Needs_Finalization
(Etype
(Func_Call
)) then
8539 Build_Finalization_Master
8541 For_Lib_Level
=> True,
8542 Insertion_Node
=> Ptr_Typ_Decl
);
8545 Make_Attribute_Reference
(Loc
,
8547 New_Occurrence_Of
(Finalization_Master
(Ptr_Typ
), Loc
),
8548 Attribute_Name
=> Name_Unrestricted_Access
);
8551 -- In other indefinite cases, pass an indication to do the allocation on
8552 -- the secondary stack and set Caller_Object to Empty so that a null
8553 -- value will be passed for the caller's object address. A transient
8554 -- scope is established to ensure eventual cleanup of the result.
8557 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8558 (Func_Call
, Function_Id
, Alloc_Form
=> Secondary_Stack
);
8559 Caller_Object
:= Empty
;
8561 Establish_Transient_Scope
(Obj_Decl
, Sec_Stack
=> True);
8564 -- Pass along any finalization master actual, which is needed in the
8565 -- case where the called function initializes a return object of an
8566 -- enclosing build-in-place function.
8568 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8569 (Func_Call
=> Func_Call
,
8570 Func_Id
=> Function_Id
,
8571 Master_Exp
=> Fmaster_Actual
);
8573 if Nkind
(Parent
(Obj_Decl
)) = N_Extended_Return_Statement
8574 and then Has_Task
(Result_Subt
)
8576 -- Here we're passing along the master that was passed in to this
8579 Add_Task_Actuals_To_Build_In_Place_Call
8580 (Func_Call
, Function_Id
,
8583 (Build_In_Place_Formal
(Encl_Func
, BIP_Task_Master
), Loc
));
8586 Add_Task_Actuals_To_Build_In_Place_Call
8587 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8590 Add_Access_Actual_To_Build_In_Place_Call
8594 Is_Access
=> Pass_Caller_Acc
);
8596 -- Finally, create an access object initialized to a reference to the
8597 -- function call. We know this access value cannot be null, so mark the
8598 -- entity accordingly to suppress the access check.
8600 Def_Id
:= Make_Temporary
(Loc
, 'R', Func_Call
);
8601 Set_Etype
(Def_Id
, Ptr_Typ
);
8602 Set_Is_Known_Non_Null
(Def_Id
);
8604 if Nkind_In
(Function_Call
, N_Type_Conversion
,
8605 N_Unchecked_Type_Conversion
)
8608 Make_Object_Declaration
(Loc
,
8609 Defining_Identifier
=> Def_Id
,
8610 Constant_Present
=> True,
8611 Object_Definition
=> New_Occurrence_Of
(Ptr_Typ
, Loc
),
8613 Make_Unchecked_Type_Conversion
(Loc
,
8614 New_Occurrence_Of
(Ptr_Typ
, Loc
),
8615 Make_Reference
(Loc
, Relocate_Node
(Func_Call
))));
8618 Make_Object_Declaration
(Loc
,
8619 Defining_Identifier
=> Def_Id
,
8620 Constant_Present
=> True,
8621 Object_Definition
=> New_Occurrence_Of
(Ptr_Typ
, Loc
),
8623 Make_Reference
(Loc
, Relocate_Node
(Func_Call
)));
8626 Insert_After_And_Analyze
(Ptr_Typ_Decl
, Res_Decl
);
8628 -- If the result subtype of the called function is definite and is not
8629 -- itself the return expression of an enclosing BIP function, then mark
8630 -- the object as having no initialization.
8632 if Definite
and then not Is_Return_Object
(Obj_Def_Id
) then
8634 -- The related object declaration is encased in a transient block
8635 -- because the build-in-place function call contains at least one
8636 -- nested function call that produces a controlled transient
8639 -- Obj : ... := BIP_Func_Call (Ctrl_Func_Call);
8641 -- Since the build-in-place expansion decouples the call from the
8642 -- object declaration, the finalization machinery lacks the context
8643 -- which prompted the generation of the transient block. To resolve
8644 -- this scenario, store the build-in-place call.
8646 if Scope_Is_Transient
and then Node_To_Be_Wrapped
= Obj_Decl
then
8647 Set_BIP_Initialization_Call
(Obj_Def_Id
, Res_Decl
);
8650 Set_Expression
(Obj_Decl
, Empty
);
8651 Set_No_Initialization
(Obj_Decl
);
8653 -- In case of an indefinite result subtype, or if the call is the
8654 -- return expression of an enclosing BIP function, rewrite the object
8655 -- declaration as an object renaming where the renamed object is a
8656 -- dereference of <function_Call>'reference:
8658 -- Obj : Subt renames <function_call>'Ref.all;
8662 Make_Explicit_Dereference
(Obj_Loc
,
8663 Prefix
=> New_Occurrence_Of
(Def_Id
, Obj_Loc
));
8666 Make_Object_Renaming_Declaration
(Obj_Loc
,
8667 Defining_Identifier
=> Make_Temporary
(Obj_Loc
, 'D'),
8669 New_Occurrence_Of
(Designated_Type
, Obj_Loc
),
8670 Name
=> Call_Deref
));
8672 -- At this point, Defining_Identifier (Obj_Decl) is no longer equal
8675 Set_Renamed_Object
(Defining_Identifier
(Obj_Decl
), Call_Deref
);
8677 -- If the original entity comes from source, then mark the new
8678 -- entity as needing debug information, even though it's defined
8679 -- by a generated renaming that does not come from source, so that
8680 -- the Materialize_Entity flag will be set on the entity when
8681 -- Debug_Renaming_Declaration is called during analysis.
8683 if Comes_From_Source
(Obj_Def_Id
) then
8684 Set_Debug_Info_Needed
(Defining_Identifier
(Obj_Decl
));
8688 Replace_Renaming_Declaration_Id
8689 (Obj_Decl
, Original_Node
(Obj_Decl
));
8691 end Make_Build_In_Place_Call_In_Object_Declaration
;
8693 -------------------------------------------------
8694 -- Make_Build_In_Place_Iface_Call_In_Allocator --
8695 -------------------------------------------------
8697 procedure Make_Build_In_Place_Iface_Call_In_Allocator
8698 (Allocator
: Node_Id
;
8699 Function_Call
: Node_Id
)
8701 BIP_Func_Call
: constant Node_Id
:=
8702 Unqual_BIP_Iface_Function_Call
(Function_Call
);
8703 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8705 Anon_Type
: Entity_Id
;
8710 -- No action of the call has already been processed
8712 if Is_Expanded_Build_In_Place_Call
(BIP_Func_Call
) then
8716 Tmp_Id
:= Make_Temporary
(Loc
, 'D');
8718 -- Insert a temporary before N initialized with the BIP function call
8719 -- without its enclosing type conversions and analyze it without its
8720 -- expansion. This temporary facilitates us reusing the BIP machinery,
8721 -- which takes care of adding the extra build-in-place actuals and
8722 -- transforms this object declaration into an object renaming
8725 Anon_Type
:= Create_Itype
(E_Anonymous_Access_Type
, Function_Call
);
8726 Set_Directly_Designated_Type
(Anon_Type
, Etype
(BIP_Func_Call
));
8727 Set_Etype
(Anon_Type
, Anon_Type
);
8730 Make_Object_Declaration
(Loc
,
8731 Defining_Identifier
=> Tmp_Id
,
8732 Object_Definition
=> New_Occurrence_Of
(Anon_Type
, Loc
),
8734 Make_Allocator
(Loc
,
8736 Make_Qualified_Expression
(Loc
,
8738 New_Occurrence_Of
(Etype
(BIP_Func_Call
), Loc
),
8739 Expression
=> New_Copy_Tree
(BIP_Func_Call
))));
8741 Expander_Mode_Save_And_Set
(False);
8742 Insert_Action
(Allocator
, Tmp_Decl
);
8743 Expander_Mode_Restore
;
8745 Make_Build_In_Place_Call_In_Allocator
8746 (Allocator
=> Expression
(Tmp_Decl
),
8747 Function_Call
=> Expression
(Expression
(Tmp_Decl
)));
8749 Rewrite
(Allocator
, New_Occurrence_Of
(Tmp_Id
, Loc
));
8750 end Make_Build_In_Place_Iface_Call_In_Allocator
;
8752 ---------------------------------------------------------
8753 -- Make_Build_In_Place_Iface_Call_In_Anonymous_Context --
8754 ---------------------------------------------------------
8756 procedure Make_Build_In_Place_Iface_Call_In_Anonymous_Context
8757 (Function_Call
: Node_Id
)
8759 BIP_Func_Call
: constant Node_Id
:=
8760 Unqual_BIP_Iface_Function_Call
(Function_Call
);
8761 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8767 -- No action of the call has already been processed
8769 if Is_Expanded_Build_In_Place_Call
(BIP_Func_Call
) then
8773 pragma Assert
(Needs_Finalization
(Etype
(BIP_Func_Call
)));
8775 -- Insert a temporary before the call initialized with function call to
8776 -- reuse the BIP machinery which takes care of adding the extra build-in
8777 -- place actuals and transforms this object declaration into an object
8778 -- renaming declaration.
8780 Tmp_Id
:= Make_Temporary
(Loc
, 'D');
8783 Make_Object_Declaration
(Loc
,
8784 Defining_Identifier
=> Tmp_Id
,
8785 Object_Definition
=>
8786 New_Occurrence_Of
(Etype
(Function_Call
), Loc
),
8787 Expression
=> Relocate_Node
(Function_Call
));
8789 Expander_Mode_Save_And_Set
(False);
8790 Insert_Action
(Function_Call
, Tmp_Decl
);
8791 Expander_Mode_Restore
;
8793 Make_Build_In_Place_Iface_Call_In_Object_Declaration
8794 (Obj_Decl
=> Tmp_Decl
,
8795 Function_Call
=> Expression
(Tmp_Decl
));
8796 end Make_Build_In_Place_Iface_Call_In_Anonymous_Context
;
8798 ----------------------------------------------------------
8799 -- Make_Build_In_Place_Iface_Call_In_Object_Declaration --
8800 ----------------------------------------------------------
8802 procedure Make_Build_In_Place_Iface_Call_In_Object_Declaration
8803 (Obj_Decl
: Node_Id
;
8804 Function_Call
: Node_Id
)
8806 BIP_Func_Call
: constant Node_Id
:=
8807 Unqual_BIP_Iface_Function_Call
(Function_Call
);
8808 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8809 Obj_Id
: constant Entity_Id
:= Defining_Entity
(Obj_Decl
);
8815 -- No action of the call has already been processed
8817 if Is_Expanded_Build_In_Place_Call
(BIP_Func_Call
) then
8821 Tmp_Id
:= Make_Temporary
(Loc
, 'D');
8823 -- Insert a temporary before N initialized with the BIP function call
8824 -- without its enclosing type conversions and analyze it without its
8825 -- expansion. This temporary facilitates us reusing the BIP machinery,
8826 -- which takes care of adding the extra build-in-place actuals and
8827 -- transforms this object declaration into an object renaming
8831 Make_Object_Declaration
(Loc
,
8832 Defining_Identifier
=> Tmp_Id
,
8833 Object_Definition
=>
8834 New_Occurrence_Of
(Etype
(BIP_Func_Call
), Loc
),
8835 Expression
=> New_Copy_Tree
(BIP_Func_Call
));
8837 Expander_Mode_Save_And_Set
(False);
8838 Insert_Action
(Obj_Decl
, Tmp_Decl
);
8839 Expander_Mode_Restore
;
8841 Make_Build_In_Place_Call_In_Object_Declaration
8842 (Obj_Decl
=> Tmp_Decl
,
8843 Function_Call
=> Expression
(Tmp_Decl
));
8845 pragma Assert
(Nkind
(Tmp_Decl
) = N_Object_Renaming_Declaration
);
8847 -- Replace the original build-in-place function call by a reference to
8848 -- the resulting temporary object renaming declaration. In this way,
8849 -- all the interface conversions performed in the original Function_Call
8850 -- on the build-in-place object are preserved.
8852 Rewrite
(BIP_Func_Call
, New_Occurrence_Of
(Tmp_Id
, Loc
));
8854 -- Replace the original object declaration by an internal object
8855 -- renaming declaration. This leaves the generated code more clean (the
8856 -- build-in-place function call in an object renaming declaration and
8857 -- displacements of the pointer to the build-in-place object in another
8858 -- renaming declaration) and allows us to invoke the routine that takes
8859 -- care of replacing the identifier of the renaming declaration (routine
8860 -- originally developed for the regular build-in-place management).
8863 Make_Object_Renaming_Declaration
(Loc
,
8864 Defining_Identifier
=> Make_Temporary
(Loc
, 'D'),
8865 Subtype_Mark
=> New_Occurrence_Of
(Etype
(Obj_Id
), Loc
),
8866 Name
=> Function_Call
));
8869 Replace_Renaming_Declaration_Id
(Obj_Decl
, Original_Node
(Obj_Decl
));
8870 end Make_Build_In_Place_Iface_Call_In_Object_Declaration
;
8872 --------------------------------------------
8873 -- Make_CPP_Constructor_Call_In_Allocator --
8874 --------------------------------------------
8876 procedure Make_CPP_Constructor_Call_In_Allocator
8877 (Allocator
: Node_Id
;
8878 Function_Call
: Node_Id
)
8880 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8881 Acc_Type
: constant Entity_Id
:= Etype
(Allocator
);
8882 Function_Id
: constant Entity_Id
:= Entity
(Name
(Function_Call
));
8883 Result_Subt
: constant Entity_Id
:= Available_View
(Etype
(Function_Id
));
8885 New_Allocator
: Node_Id
;
8886 Return_Obj_Access
: Entity_Id
;
8890 pragma Assert
(Nkind
(Allocator
) = N_Allocator
8891 and then Nkind
(Function_Call
) = N_Function_Call
);
8892 pragma Assert
(Convention
(Function_Id
) = Convention_CPP
8893 and then Is_Constructor
(Function_Id
));
8894 pragma Assert
(Is_Constrained
(Underlying_Type
(Result_Subt
)));
8896 -- Replace the initialized allocator of form "new T'(Func (...))" with
8897 -- an uninitialized allocator of form "new T", where T is the result
8898 -- subtype of the called function. The call to the function is handled
8899 -- separately further below.
8902 Make_Allocator
(Loc
,
8903 Expression
=> New_Occurrence_Of
(Result_Subt
, Loc
));
8904 Set_No_Initialization
(New_Allocator
);
8906 -- Copy attributes to new allocator. Note that the new allocator
8907 -- logically comes from source if the original one did, so copy the
8908 -- relevant flag. This ensures proper treatment of the restriction
8909 -- No_Implicit_Heap_Allocations in this case.
8911 Set_Storage_Pool
(New_Allocator
, Storage_Pool
(Allocator
));
8912 Set_Procedure_To_Call
(New_Allocator
, Procedure_To_Call
(Allocator
));
8913 Set_Comes_From_Source
(New_Allocator
, Comes_From_Source
(Allocator
));
8915 Rewrite
(Allocator
, New_Allocator
);
8917 -- Create a new access object and initialize it to the result of the
8918 -- new uninitialized allocator. Note: we do not use Allocator as the
8919 -- Related_Node of Return_Obj_Access in call to Make_Temporary below
8920 -- as this would create a sort of infinite "recursion".
8922 Return_Obj_Access
:= Make_Temporary
(Loc
, 'R');
8923 Set_Etype
(Return_Obj_Access
, Acc_Type
);
8926 -- Rnnn : constant ptr_T := new (T);
8927 -- Init (Rnn.all,...);
8930 Make_Object_Declaration
(Loc
,
8931 Defining_Identifier
=> Return_Obj_Access
,
8932 Constant_Present
=> True,
8933 Object_Definition
=> New_Occurrence_Of
(Acc_Type
, Loc
),
8934 Expression
=> Relocate_Node
(Allocator
));
8935 Insert_Action
(Allocator
, Tmp_Obj
);
8937 Insert_List_After_And_Analyze
(Tmp_Obj
,
8938 Build_Initialization_Call
(Loc
,
8940 Make_Explicit_Dereference
(Loc
,
8941 Prefix
=> New_Occurrence_Of
(Return_Obj_Access
, Loc
)),
8942 Typ
=> Etype
(Function_Id
),
8943 Constructor_Ref
=> Function_Call
));
8945 -- Finally, replace the allocator node with a reference to the result of
8946 -- the function call itself (which will effectively be an access to the
8947 -- object created by the allocator).
8949 Rewrite
(Allocator
, New_Occurrence_Of
(Return_Obj_Access
, Loc
));
8951 -- Ada 2005 (AI-251): If the type of the allocator is an interface then
8952 -- generate an implicit conversion to force displacement of the "this"
8955 if Is_Interface
(Designated_Type
(Acc_Type
)) then
8956 Rewrite
(Allocator
, Convert_To
(Acc_Type
, Relocate_Node
(Allocator
)));
8959 Analyze_And_Resolve
(Allocator
, Acc_Type
);
8960 end Make_CPP_Constructor_Call_In_Allocator
;
8962 -----------------------------------
8963 -- Needs_BIP_Finalization_Master --
8964 -----------------------------------
8966 function Needs_BIP_Finalization_Master
8967 (Func_Id
: Entity_Id
) return Boolean
8969 pragma Assert
(Is_Build_In_Place_Function
(Func_Id
));
8970 Func_Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
8972 -- A formal giving the finalization master is needed for build-in-place
8973 -- functions whose result type needs finalization or is a tagged type.
8974 -- Tagged primitive build-in-place functions need such a formal because
8975 -- they can be called by a dispatching call, and extensions may require
8976 -- finalization even if the root type doesn't. This means they're also
8977 -- needed for tagged nonprimitive build-in-place functions with tagged
8978 -- results, since such functions can be called via access-to-function
8979 -- types, and those can be used to call primitives, so masters have to
8980 -- be passed to all such build-in-place functions, primitive or not.
8983 not Restriction_Active
(No_Finalization
)
8984 and then (Needs_Finalization
(Func_Typ
)
8985 or else Is_Tagged_Type
(Func_Typ
));
8986 end Needs_BIP_Finalization_Master
;
8988 --------------------------
8989 -- Needs_BIP_Alloc_Form --
8990 --------------------------
8992 function Needs_BIP_Alloc_Form
(Func_Id
: Entity_Id
) return Boolean is
8993 pragma Assert
(Is_Build_In_Place_Function
(Func_Id
));
8994 Func_Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
8996 return not Is_Constrained
(Func_Typ
) or else Is_Tagged_Type
(Func_Typ
);
8997 end Needs_BIP_Alloc_Form
;
8999 --------------------------------------
9000 -- Needs_Result_Accessibility_Level --
9001 --------------------------------------
9003 function Needs_Result_Accessibility_Level
9004 (Func_Id
: Entity_Id
) return Boolean
9006 Func_Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
9008 function Has_Unconstrained_Access_Discriminant_Component
9009 (Comp_Typ
: Entity_Id
) return Boolean;
9010 -- Returns True if any component of the type has an unconstrained access
9013 -----------------------------------------------------
9014 -- Has_Unconstrained_Access_Discriminant_Component --
9015 -----------------------------------------------------
9017 function Has_Unconstrained_Access_Discriminant_Component
9018 (Comp_Typ
: Entity_Id
) return Boolean
9021 if not Is_Limited_Type
(Comp_Typ
) then
9024 -- Only limited types can have access discriminants with
9027 elsif Has_Unconstrained_Access_Discriminants
(Comp_Typ
) then
9030 elsif Is_Array_Type
(Comp_Typ
) then
9031 return Has_Unconstrained_Access_Discriminant_Component
9032 (Underlying_Type
(Component_Type
(Comp_Typ
)));
9034 elsif Is_Record_Type
(Comp_Typ
) then
9039 Comp
:= First_Component
(Comp_Typ
);
9040 while Present
(Comp
) loop
9041 if Has_Unconstrained_Access_Discriminant_Component
9042 (Underlying_Type
(Etype
(Comp
)))
9047 Next_Component
(Comp
);
9053 end Has_Unconstrained_Access_Discriminant_Component
;
9055 Feature_Disabled
: constant Boolean := True;
9058 -- Start of processing for Needs_Result_Accessibility_Level
9061 -- False if completion unavailable (how does this happen???)
9063 if not Present
(Func_Typ
) then
9066 elsif Feature_Disabled
then
9069 -- False if not a function, also handle enum-lit renames case
9071 elsif Func_Typ
= Standard_Void_Type
9072 or else Is_Scalar_Type
(Func_Typ
)
9076 -- Handle a corner case, a cross-dialect subp renaming. For example,
9077 -- an Ada 2012 renaming of an Ada 2005 subprogram. This can occur when
9078 -- an Ada 2005 (or earlier) unit references predefined run-time units.
9080 elsif Present
(Alias
(Func_Id
)) then
9082 -- Unimplemented: a cross-dialect subp renaming which does not set
9083 -- the Alias attribute (e.g., a rename of a dereference of an access
9084 -- to subprogram value). ???
9086 return Present
(Extra_Accessibility_Of_Result
(Alias
(Func_Id
)));
9088 -- Remaining cases require Ada 2012 mode
9090 elsif Ada_Version
< Ada_2012
then
9093 elsif Ekind
(Func_Typ
) = E_Anonymous_Access_Type
9094 or else Is_Tagged_Type
(Func_Typ
)
9096 -- In the case of, say, a null tagged record result type, the need
9097 -- for this extra parameter might not be obvious. This function
9098 -- returns True for all tagged types for compatibility reasons.
9099 -- A function with, say, a tagged null controlling result type might
9100 -- be overridden by a primitive of an extension having an access
9101 -- discriminant and the overrider and overridden must have compatible
9102 -- calling conventions (including implicitly declared parameters).
9103 -- Similarly, values of one access-to-subprogram type might designate
9104 -- both a primitive subprogram of a given type and a function
9105 -- which is, for example, not a primitive subprogram of any type.
9106 -- Again, this requires calling convention compatibility.
9107 -- It might be possible to solve these issues by introducing
9108 -- wrappers, but that is not the approach that was chosen.
9112 elsif Has_Unconstrained_Access_Discriminants
(Func_Typ
) then
9115 elsif Has_Unconstrained_Access_Discriminant_Component
(Func_Typ
) then
9118 -- False for all other cases
9123 end Needs_Result_Accessibility_Level
;
9125 -------------------------------------
9126 -- Replace_Renaming_Declaration_Id --
9127 -------------------------------------
9129 procedure Replace_Renaming_Declaration_Id
9130 (New_Decl
: Node_Id
;
9131 Orig_Decl
: Node_Id
)
9133 New_Id
: constant Entity_Id
:= Defining_Entity
(New_Decl
);
9134 Orig_Id
: constant Entity_Id
:= Defining_Entity
(Orig_Decl
);
9137 Set_Chars
(New_Id
, Chars
(Orig_Id
));
9139 -- Swap next entity links in preparation for exchanging entities
9142 Next_Id
: constant Entity_Id
:= Next_Entity
(New_Id
);
9144 Set_Next_Entity
(New_Id
, Next_Entity
(Orig_Id
));
9145 Set_Next_Entity
(Orig_Id
, Next_Id
);
9148 Set_Homonym
(New_Id
, Homonym
(Orig_Id
));
9149 Exchange_Entities
(New_Id
, Orig_Id
);
9151 -- Preserve source indication of original declaration, so that xref
9152 -- information is properly generated for the right entity.
9154 Preserve_Comes_From_Source
(New_Decl
, Orig_Decl
);
9155 Preserve_Comes_From_Source
(Orig_Id
, Orig_Decl
);
9157 Set_Comes_From_Source
(New_Id
, False);
9158 end Replace_Renaming_Declaration_Id
;
9160 ---------------------------------
9161 -- Rewrite_Function_Call_For_C --
9162 ---------------------------------
9164 procedure Rewrite_Function_Call_For_C
(N
: Node_Id
) is
9165 Orig_Func
: constant Entity_Id
:= Entity
(Name
(N
));
9166 Func_Id
: constant Entity_Id
:= Ultimate_Alias
(Orig_Func
);
9167 Par
: constant Node_Id
:= Parent
(N
);
9168 Proc_Id
: constant Entity_Id
:= Corresponding_Procedure
(Func_Id
);
9169 Loc
: constant Source_Ptr
:= Sloc
(Par
);
9171 Last_Actual
: Node_Id
;
9172 Last_Formal
: Entity_Id
;
9174 -- Start of processing for Rewrite_Function_Call_For_C
9177 -- The actuals may be given by named associations, so the added actual
9178 -- that is the target of the return value of the call must be a named
9179 -- association as well, so we retrieve the name of the generated
9182 Last_Formal
:= First_Formal
(Proc_Id
);
9183 while Present
(Next_Formal
(Last_Formal
)) loop
9184 Last_Formal
:= Next_Formal
(Last_Formal
);
9187 Actuals
:= Parameter_Associations
(N
);
9189 -- The original function may lack parameters
9191 if No
(Actuals
) then
9192 Actuals
:= New_List
;
9195 -- If the function call is the expression of an assignment statement,
9196 -- transform the assignment into a procedure call. Generate:
9198 -- LHS := Func_Call (...);
9200 -- Proc_Call (..., LHS);
9202 -- If function is inherited, a conversion may be necessary.
9204 if Nkind
(Par
) = N_Assignment_Statement
then
9205 Last_Actual
:= Name
(Par
);
9207 if not Comes_From_Source
(Orig_Func
)
9208 and then Etype
(Orig_Func
) /= Etype
(Func_Id
)
9211 Make_Type_Conversion
(Loc
,
9212 New_Occurrence_Of
(Etype
(Func_Id
), Loc
),
9217 Make_Parameter_Association
(Loc
,
9219 Make_Identifier
(Loc
, Chars
(Last_Formal
)),
9220 Explicit_Actual_Parameter
=> Last_Actual
));
9223 Make_Procedure_Call_Statement
(Loc
,
9224 Name
=> New_Occurrence_Of
(Proc_Id
, Loc
),
9225 Parameter_Associations
=> Actuals
));
9228 -- Otherwise the context is an expression. Generate a temporary and a
9229 -- procedure call to obtain the function result. Generate:
9231 -- ... Func_Call (...) ...
9234 -- Proc_Call (..., Temp);
9239 Temp_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
9248 Make_Object_Declaration
(Loc
,
9249 Defining_Identifier
=> Temp_Id
,
9250 Object_Definition
=>
9251 New_Occurrence_Of
(Etype
(Func_Id
), Loc
));
9254 -- Proc_Call (..., Temp);
9257 Make_Parameter_Association
(Loc
,
9259 Make_Identifier
(Loc
, Chars
(Last_Formal
)),
9260 Explicit_Actual_Parameter
=>
9261 New_Occurrence_Of
(Temp_Id
, Loc
)));
9264 Make_Procedure_Call_Statement
(Loc
,
9265 Name
=> New_Occurrence_Of
(Proc_Id
, Loc
),
9266 Parameter_Associations
=> Actuals
);
9268 Insert_Actions
(Par
, New_List
(Decl
, Call
));
9269 Rewrite
(N
, New_Occurrence_Of
(Temp_Id
, Loc
));
9272 end Rewrite_Function_Call_For_C
;
9274 ------------------------------------
9275 -- Set_Enclosing_Sec_Stack_Return --
9276 ------------------------------------
9278 procedure Set_Enclosing_Sec_Stack_Return
(N
: Node_Id
) is
9282 -- Due to a possible mix of internally generated blocks, source blocks
9283 -- and loops, the scope stack may not be contiguous as all labels are
9284 -- inserted at the top level within the related function. Instead,
9285 -- perform a parent-based traversal and mark all appropriate constructs.
9287 while Present
(P
) loop
9289 -- Mark the label of a source or internally generated block or
9292 if Nkind_In
(P
, N_Block_Statement
, N_Loop_Statement
) then
9293 Set_Sec_Stack_Needed_For_Return
(Entity
(Identifier
(P
)));
9295 -- Mark the enclosing function
9297 elsif Nkind
(P
) = N_Subprogram_Body
then
9298 if Present
(Corresponding_Spec
(P
)) then
9299 Set_Sec_Stack_Needed_For_Return
(Corresponding_Spec
(P
));
9301 Set_Sec_Stack_Needed_For_Return
(Defining_Entity
(P
));
9304 -- Do not go beyond the enclosing function
9311 end Set_Enclosing_Sec_Stack_Return
;
9313 ------------------------------------
9314 -- Unqual_BIP_Iface_Function_Call --
9315 ------------------------------------
9317 function Unqual_BIP_Iface_Function_Call
(Expr
: Node_Id
) return Node_Id
is
9318 Has_Pointer_Displacement
: Boolean := False;
9319 On_Object_Declaration
: Boolean := False;
9320 -- Remember if processing the renaming expressions on recursion we have
9321 -- traversed an object declaration, since we can traverse many object
9322 -- declaration renamings but just one regular object declaration.
9324 function Unqual_BIP_Function_Call
(Expr
: Node_Id
) return Node_Id
;
9325 -- Search for a build-in-place function call skipping any qualification
9326 -- including qualified expressions, type conversions, references, calls
9327 -- to displace the pointer to the object, and renamings. Return Empty if
9328 -- no build-in-place function call is found.
9330 ------------------------------
9331 -- Unqual_BIP_Function_Call --
9332 ------------------------------
9334 function Unqual_BIP_Function_Call
(Expr
: Node_Id
) return Node_Id
is
9336 -- Recurse to handle case of multiple levels of qualification and/or
9339 if Nkind_In
(Expr
, N_Qualified_Expression
,
9341 N_Unchecked_Type_Conversion
)
9343 return Unqual_BIP_Function_Call
(Expression
(Expr
));
9345 -- Recurse to handle case of multiple levels of references and
9346 -- explicit dereferences.
9348 elsif Nkind_In
(Expr
, N_Attribute_Reference
,
9349 N_Explicit_Dereference
,
9352 return Unqual_BIP_Function_Call
(Prefix
(Expr
));
9354 -- Recurse on object renamings
9356 elsif Nkind
(Expr
) = N_Identifier
9357 and then Present
(Entity
(Expr
))
9358 and then Ekind_In
(Entity
(Expr
), E_Constant
, E_Variable
)
9359 and then Nkind
(Parent
(Entity
(Expr
))) =
9360 N_Object_Renaming_Declaration
9361 and then Present
(Renamed_Object
(Entity
(Expr
)))
9363 return Unqual_BIP_Function_Call
(Renamed_Object
(Entity
(Expr
)));
9365 -- Recurse on the initializing expression of the first reference of
9366 -- an object declaration.
9368 elsif not On_Object_Declaration
9369 and then Nkind
(Expr
) = N_Identifier
9370 and then Present
(Entity
(Expr
))
9371 and then Ekind_In
(Entity
(Expr
), E_Constant
, E_Variable
)
9372 and then Nkind
(Parent
(Entity
(Expr
))) = N_Object_Declaration
9373 and then Present
(Expression
(Parent
(Entity
(Expr
))))
9375 On_Object_Declaration
:= True;
9377 Unqual_BIP_Function_Call
(Expression
(Parent
(Entity
(Expr
))));
9379 -- Recurse to handle calls to displace the pointer to the object to
9380 -- reference a secondary dispatch table.
9382 elsif Nkind
(Expr
) = N_Function_Call
9383 and then Nkind
(Name
(Expr
)) in N_Has_Entity
9384 and then Present
(Entity
(Name
(Expr
)))
9385 and then RTU_Loaded
(Ada_Tags
)
9386 and then RTE_Available
(RE_Displace
)
9387 and then Is_RTE
(Entity
(Name
(Expr
)), RE_Displace
)
9389 Has_Pointer_Displacement
:= True;
9391 Unqual_BIP_Function_Call
(First
(Parameter_Associations
(Expr
)));
9393 -- Normal case: check if the inner expression is a BIP function call
9394 -- and the pointer to the object is displaced.
9396 elsif Has_Pointer_Displacement
9397 and then Is_Build_In_Place_Function_Call
(Expr
)
9404 end Unqual_BIP_Function_Call
;
9406 -- Start of processing for Unqual_BIP_Iface_Function_Call
9409 if Nkind
(Expr
) = N_Identifier
and then No
(Entity
(Expr
)) then
9411 -- Can happen for X'Elab_Spec in the binder-generated file
9416 return Unqual_BIP_Function_Call
(Expr
);
9417 end Unqual_BIP_Iface_Function_Call
;