1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2023, 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 Accessibility
; use Accessibility
;
27 with Atree
; use Atree
;
28 with Aspects
; use Aspects
;
29 with Checks
; use Checks
;
30 with Debug
; use Debug
;
31 with Einfo
; use Einfo
;
32 with Einfo
.Entities
; use Einfo
.Entities
;
33 with Einfo
.Utils
; use Einfo
.Utils
;
34 with Errout
; use Errout
;
35 with Elists
; use Elists
;
36 with Expander
; use Expander
;
37 with Exp_Aggr
; use Exp_Aggr
;
38 with Exp_Atag
; use Exp_Atag
;
39 with Exp_Ch3
; use Exp_Ch3
;
40 with Exp_Ch7
; use Exp_Ch7
;
41 with Exp_Ch9
; use Exp_Ch9
;
42 with Exp_Dbug
; use Exp_Dbug
;
43 with Exp_Disp
; use Exp_Disp
;
44 with Exp_Dist
; use Exp_Dist
;
45 with Exp_Intr
; use Exp_Intr
;
46 with Exp_Pakd
; use Exp_Pakd
;
47 with Exp_Tss
; use Exp_Tss
;
48 with Exp_Util
; use Exp_Util
;
49 with Freeze
; use Freeze
;
50 with Inline
; use Inline
;
51 with Itypes
; use Itypes
;
53 with Namet
; use Namet
;
54 with Nlists
; use Nlists
;
55 with Nmake
; use Nmake
;
57 with Restrict
; use Restrict
;
58 with Rident
; use Rident
;
59 with Rtsfind
; use Rtsfind
;
61 with Sem_Aux
; use Sem_Aux
;
62 with Sem_Ch6
; use Sem_Ch6
;
63 with Sem_Ch8
; use Sem_Ch8
;
64 with Sem_Ch13
; use Sem_Ch13
;
65 with Sem_Dim
; use Sem_Dim
;
66 with Sem_Disp
; use Sem_Disp
;
67 with Sem_Dist
; use Sem_Dist
;
68 with Sem_Eval
; use Sem_Eval
;
69 with Sem_Mech
; use Sem_Mech
;
70 with Sem_Res
; use Sem_Res
;
71 with Sem_SCIL
; use Sem_SCIL
;
72 with Sem_Util
; use Sem_Util
;
73 with Sinfo
; use Sinfo
;
74 with Sinfo
.Nodes
; use Sinfo
.Nodes
;
75 with Sinfo
.Utils
; use Sinfo
.Utils
;
76 with Sinput
; use Sinput
;
77 with Snames
; use Snames
;
78 with Stand
; use Stand
;
79 with Stringt
; use Stringt
;
80 with Tbuild
; use Tbuild
;
81 with Uintp
; use Uintp
;
82 with Validsw
; use Validsw
;
84 package body Exp_Ch6
is
86 --------------------------------
87 -- Function return mechanisms --
88 --------------------------------
90 -- This is a summary of the various function return mechanisms implemented
91 -- in GNAT for Ada 2005 and later versions of the language. In the below
92 -- table, the first column must be read as an if expression: if the result
93 -- type of the function is limited, then the return mechanism is and ...;
94 -- elsif the result type is indefinite or large definite, then ...; elsif
95 -- ...; else ... The different mechanisms are implemented either in the
96 -- front end, or in the back end, or partly in both ends, depending on the
99 -- Result type | Return mechanism | Front end | Back end
100 -- --------------------------------------------------------------------
102 -- Limited Build In Place All
104 -- Indefinite/ Secondary Stack Needs Fin. Others
107 -- Needs Fin. Secondary Stack All
110 -- Needs Fin. Invisible Parameter All All
111 -- (BERS True) (return) (call)
113 -- By Reference Invisible Parameter All
115 -- Others Primary stack/ All
118 -- Needs Fin.: type needs finalization [RM 7.6(9.1/2-9.6/2)]
119 -- BERS: Opt.Back_End_Return_Slot setting
121 -- The table is valid for all calls except for those dispatching on result;
122 -- the latter calls are considered as returning a class-wide type and thus
123 -- always return on the secondary stack, with the help of a small wrapper
124 -- function (thunk) if the original result type is not itself returned on
125 -- the secondary stack as per the above table.
127 -- Suffixes for Build-In-Place extra formals
129 BIP_Alloc_Suffix
: constant String := "BIPalloc";
130 BIP_Storage_Pool_Suffix
: constant String := "BIPstoragepool";
131 BIP_Finalization_Master_Suffix
: constant String := "BIPfinalizationmaster";
132 BIP_Task_Master_Suffix
: constant String := "BIPtaskmaster";
133 BIP_Activation_Chain_Suffix
: constant String := "BIPactivationchain";
134 BIP_Object_Access_Suffix
: constant String := "BIPaccess";
136 -----------------------
137 -- Local Subprograms --
138 -----------------------
140 procedure Add_Access_Actual_To_Build_In_Place_Call
141 (Function_Call
: Node_Id
;
142 Function_Id
: Entity_Id
;
143 Return_Object
: Node_Id
;
144 Is_Access
: Boolean := False);
145 -- Ada 2005 (AI-318-02): Apply the Unrestricted_Access attribute to the
146 -- object name given by Return_Object and add the attribute to the end of
147 -- the actual parameter list associated with the build-in-place function
148 -- call denoted by Function_Call. However, if Is_Access is True, then
149 -- Return_Object is already an access expression, in which case it's passed
150 -- along directly to the build-in-place function. Finally, if Return_Object
151 -- is empty, then pass a null literal as the actual.
153 procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
154 (Function_Call
: Node_Id
;
155 Function_Id
: Entity_Id
;
156 Alloc_Form
: BIP_Allocation_Form
:= Unspecified
;
157 Alloc_Form_Exp
: Node_Id
:= Empty
;
158 Pool_Actual
: Node_Id
:= Make_Null
(No_Location
));
159 -- Ada 2005 (AI-318-02): Add the actuals needed for a build-in-place
160 -- function call that returns a caller-unknown-size result (BIP_Alloc_Form
161 -- and BIP_Storage_Pool). If Alloc_Form_Exp is present, then use it,
162 -- otherwise pass a literal corresponding to the Alloc_Form parameter
163 -- (which must not be Unspecified in that case). Pool_Actual is the
164 -- parameter to pass to BIP_Storage_Pool.
166 procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
167 (Func_Call
: Node_Id
;
169 Ptr_Typ
: Entity_Id
:= Empty
;
170 Master_Exp
: Node_Id
:= Empty
);
171 -- Ada 2005 (AI-318-02): If the result type of a build-in-place call needs
172 -- finalization actions, add an actual parameter which is a pointer to the
173 -- finalization master of the caller. If Master_Exp is not Empty, then that
174 -- will be passed as the actual. Otherwise, if Ptr_Typ is left Empty, this
175 -- will result in an automatic "null" value for the actual.
177 procedure Add_Task_Actuals_To_Build_In_Place_Call
178 (Function_Call
: Node_Id
;
179 Function_Id
: Entity_Id
;
180 Master_Actual
: Node_Id
;
181 Chain
: Node_Id
:= Empty
);
182 -- Ada 2005 (AI-318-02): For a build-in-place call, if the result type
183 -- contains tasks, add two actual parameters: the master, and a pointer to
184 -- the caller's activation chain. Master_Actual is the actual parameter
185 -- expression to pass for the master. In most cases, this is the current
186 -- master (_master). The two exceptions are: If the function call is the
187 -- initialization expression for an allocator, we pass the master of the
188 -- access type. If the function call is the initialization expression for a
189 -- return object, we pass along the master passed in by the caller. In most
190 -- contexts, the activation chain to pass is the local one, which is
191 -- indicated by No (Chain). However, in an allocator, the caller passes in
192 -- the activation Chain. Note: Master_Actual can be Empty, but only if
193 -- there are no tasks.
195 function Caller_Known_Size
196 (Func_Call
: Node_Id
;
197 Result_Subt
: Entity_Id
) return Boolean;
198 -- True if result subtype is definite or has a size that does not require
199 -- secondary stack usage (i.e. no variant part or components whose type
200 -- depends on discriminants). In particular, untagged types with only
201 -- access discriminants do not require secondary stack use. Note we must
202 -- always use the secondary stack for dispatching-on-result calls.
204 function Check_BIP_Actuals
205 (Subp_Call
: Node_Id
;
206 Subp_Id
: Entity_Id
) return Boolean;
207 -- Given a subprogram call to the given subprogram return True if the
208 -- names of BIP extra actual and formal parameters match, and the number
209 -- of actuals (including extra actuals) matches the number of formals.
211 function Check_Number_Of_Actuals
212 (Subp_Call
: Node_Id
;
213 Subp_Id
: Entity_Id
) return Boolean;
214 -- Given a subprogram call to the given subprogram return True if the
215 -- number of actual parameters (including extra actuals) is correct.
217 procedure Check_Overriding_Operation
(Subp
: Entity_Id
);
218 -- Subp is a dispatching operation. Check whether it may override an
219 -- inherited private operation, in which case its DT entry is that of
220 -- the hidden operation, not the one it may have received earlier.
221 -- This must be done before emitting the code to set the corresponding
222 -- DT to the address of the subprogram. The actual placement of Subp in
223 -- the proper place in the list of primitive operations is done in
224 -- Declare_Inherited_Private_Subprograms, which also has to deal with
225 -- implicit operations. This duplication is unavoidable for now???
227 procedure Detect_Infinite_Recursion
(N
: Node_Id
; Spec
: Entity_Id
);
228 -- This procedure is called only if the subprogram body N, whose spec
229 -- has the given entity Spec, contains a parameterless recursive call.
230 -- It attempts to generate runtime code to detect if this a case of
231 -- infinite recursion.
233 -- The body is scanned to determine dependencies. If the only external
234 -- dependencies are on a small set of scalar variables, then the values
235 -- of these variables are captured on entry to the subprogram, and if
236 -- the values are not changed for the call, we know immediately that
237 -- we have an infinite recursion.
239 procedure Expand_Actuals
242 Post_Call
: out List_Id
);
243 -- Return a list of actions to take place after the call in Post_Call. The
244 -- call will later be rewritten as an Expression_With_Actions, with the
245 -- Post_Call actions inserted, and the call inside.
247 -- For each actual of an in-out or out parameter which is a numeric (view)
248 -- conversion of the form T (A), where A denotes a variable, we insert the
251 -- Temp : T[ := T (A)];
253 -- prior to the call. Then we replace the actual with a reference to Temp,
254 -- and append the assignment:
256 -- A := TypeA (Temp);
258 -- after the call. Here TypeA is the actual type of variable A. For out
259 -- parameters, the initial declaration has no expression. If A is not an
260 -- entity name, we generate instead:
262 -- Var : TypeA renames A;
263 -- Temp : T := Var; -- omitting expression for out parameter.
265 -- Var := TypeA (Temp);
267 -- For other in-out parameters, we emit the required constraint checks
268 -- before and/or after the call.
270 -- For all parameter modes, actuals that denote components and slices of
271 -- packed arrays are expanded into suitable temporaries.
273 -- For nonscalar objects that are possibly unaligned, add call by copy code
274 -- (copy in for IN and IN OUT, copy out for OUT and IN OUT).
276 -- For OUT and IN OUT parameters, add predicate checks after the call
277 -- based on the predicates of the actual type.
279 procedure Expand_Call_Helper
(N
: Node_Id
; Post_Call
: out List_Id
);
280 -- Does the main work of Expand_Call. Post_Call is as for Expand_Actuals.
282 procedure Expand_Ctrl_Function_Call
(N
: Node_Id
; Use_Sec_Stack
: Boolean);
283 -- N is a function call which returns a controlled object. Transform the
284 -- call into a temporary which retrieves the returned object from the
285 -- primary or secondary stack (Use_Sec_Stack says which) using 'reference.
287 procedure Expand_Non_Function_Return
(N
: Node_Id
);
288 -- Expand a simple return statement found in a procedure body, entry body,
289 -- accept statement, or an extended return statement. Note that all non-
290 -- function returns are simple return statements.
292 function Expand_Protected_Object_Reference
294 Scop
: Entity_Id
) return Node_Id
;
296 procedure Expand_Protected_Subprogram_Call
300 -- A call to a protected subprogram within the protected object may appear
301 -- as a regular call. The list of actuals must be expanded to contain a
302 -- reference to the object itself, and the call becomes a call to the
303 -- corresponding protected subprogram.
305 procedure Expand_Simple_Function_Return
(N
: Node_Id
);
306 -- Expand simple return from function. In the case where we are returning
307 -- from a function body this is called by Expand_N_Simple_Return_Statement.
309 procedure Insert_Post_Call_Actions
(N
: Node_Id
; Post_Call
: List_Id
);
310 -- Insert the Post_Call list previously produced by routine Expand_Actuals
311 -- or Expand_Call_Helper into the tree.
313 procedure Replace_Renaming_Declaration_Id
315 Orig_Decl
: Node_Id
);
316 -- Replace the internal identifier of the new renaming declaration New_Decl
317 -- with the identifier of its original declaration Orig_Decl exchanging the
318 -- entities containing their defining identifiers to ensure the correct
319 -- replacement of the object declaration by the object renaming declaration
320 -- to avoid homograph conflicts (since the object declaration's defining
321 -- identifier was already entered in the current scope). The Next_Entity
322 -- links of the two entities are also swapped since the entities are part
323 -- of the return scope's entity list and the list structure would otherwise
324 -- be corrupted. The homonym chain is preserved as well.
326 procedure Rewrite_Function_Call_For_C
(N
: Node_Id
);
327 -- When generating C code, replace a call to a function that returns an
328 -- array into the generated procedure with an additional out parameter.
330 procedure Set_Enclosing_Sec_Stack_Return
(N
: Node_Id
);
331 -- N is a return statement for a function that returns its result on the
332 -- secondary stack. This sets the Sec_Stack_Needed_For_Return flag on the
333 -- function and all blocks and loops that the return statement is jumping
334 -- out of. This ensures that the secondary stack is not released; otherwise
335 -- the function result would be reclaimed before returning to the caller.
337 procedure Warn_BIP
(Func_Call
: Node_Id
);
338 -- Give a warning on a build-in-place function call if the -gnatd_B switch
341 ----------------------------------------------
342 -- Add_Access_Actual_To_Build_In_Place_Call --
343 ----------------------------------------------
345 procedure Add_Access_Actual_To_Build_In_Place_Call
346 (Function_Call
: Node_Id
;
347 Function_Id
: Entity_Id
;
348 Return_Object
: Node_Id
;
349 Is_Access
: Boolean := False)
351 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
352 Obj_Address
: Node_Id
;
353 Obj_Acc_Formal
: Entity_Id
;
356 -- Locate the implicit access parameter in the called function
358 Obj_Acc_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Object_Access
);
360 -- If no return object is provided, then pass null
362 if No
(Return_Object
) then
363 Obj_Address
:= Make_Null
(Loc
);
364 Set_Parent
(Obj_Address
, Function_Call
);
366 -- If Return_Object is already an expression of an access type, then use
367 -- it directly, since it must be an access value denoting the return
368 -- object, and couldn't possibly be the return object itself.
371 Obj_Address
:= Return_Object
;
372 Set_Parent
(Obj_Address
, Function_Call
);
374 -- Apply Unrestricted_Access to caller's return object
378 Make_Attribute_Reference
(Loc
,
379 Prefix
=> Return_Object
,
380 Attribute_Name
=> Name_Unrestricted_Access
);
382 Set_Parent
(Return_Object
, Obj_Address
);
383 Set_Parent
(Obj_Address
, Function_Call
);
386 Analyze_And_Resolve
(Obj_Address
, Etype
(Obj_Acc_Formal
));
388 -- Build the parameter association for the new actual and add it to the
389 -- end of the function's actuals.
391 Add_Extra_Actual_To_Call
(Function_Call
, Obj_Acc_Formal
, Obj_Address
);
392 end Add_Access_Actual_To_Build_In_Place_Call
;
394 ------------------------------------------------------
395 -- Add_Unconstrained_Actuals_To_Build_In_Place_Call --
396 ------------------------------------------------------
398 procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
399 (Function_Call
: Node_Id
;
400 Function_Id
: Entity_Id
;
401 Alloc_Form
: BIP_Allocation_Form
:= Unspecified
;
402 Alloc_Form_Exp
: Node_Id
:= Empty
;
403 Pool_Actual
: Node_Id
:= Make_Null
(No_Location
))
405 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
407 Alloc_Form_Actual
: Node_Id
;
408 Alloc_Form_Formal
: Node_Id
;
409 Pool_Formal
: Node_Id
;
412 -- Nothing to do when the size of the object is known, and the caller is
413 -- in charge of allocating it, and the callee doesn't unconditionally
414 -- require an allocation form (such as due to having a tagged result).
416 if not Needs_BIP_Alloc_Form
(Function_Id
) then
420 -- Locate the implicit allocation form parameter in the called function.
421 -- Maybe it would be better for each implicit formal of a build-in-place
422 -- function to have a flag or a Uint attribute to identify it. ???
424 Alloc_Form_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Alloc_Form
);
426 if Present
(Alloc_Form_Exp
) then
427 pragma Assert
(Alloc_Form
= Unspecified
);
429 Alloc_Form_Actual
:= Alloc_Form_Exp
;
432 pragma Assert
(Alloc_Form
/= Unspecified
);
435 Make_Integer_Literal
(Loc
,
436 Intval
=> UI_From_Int
(BIP_Allocation_Form
'Pos (Alloc_Form
)));
439 Analyze_And_Resolve
(Alloc_Form_Actual
, Etype
(Alloc_Form_Formal
));
441 -- Build the parameter association for the new actual and add it to the
442 -- end of the function's actuals.
444 Add_Extra_Actual_To_Call
445 (Function_Call
, Alloc_Form_Formal
, Alloc_Form_Actual
);
447 -- Pass the Storage_Pool parameter. This parameter is omitted on ZFP as
448 -- those targets do not support pools.
450 if RTE_Available
(RE_Root_Storage_Pool_Ptr
) then
451 Pool_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Storage_Pool
);
452 Analyze_And_Resolve
(Pool_Actual
, Etype
(Pool_Formal
));
453 Add_Extra_Actual_To_Call
454 (Function_Call
, Pool_Formal
, Pool_Actual
);
456 end Add_Unconstrained_Actuals_To_Build_In_Place_Call
;
458 -----------------------------------------------------------
459 -- Add_Finalization_Master_Actual_To_Build_In_Place_Call --
460 -----------------------------------------------------------
462 procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
463 (Func_Call
: Node_Id
;
465 Ptr_Typ
: Entity_Id
:= Empty
;
466 Master_Exp
: Node_Id
:= Empty
)
469 if not Needs_BIP_Finalization_Master
(Func_Id
) then
474 Formal
: constant Entity_Id
:=
475 Build_In_Place_Formal
(Func_Id
, BIP_Finalization_Master
);
476 Loc
: constant Source_Ptr
:= Sloc
(Func_Call
);
479 Desig_Typ
: Entity_Id
;
482 -- If there is a finalization master actual, such as the implicit
483 -- finalization master of an enclosing build-in-place function,
484 -- then this must be added as an extra actual of the call.
486 if Present
(Master_Exp
) then
487 Actual
:= Master_Exp
;
489 -- Case where the context does not require an actual master
491 elsif No
(Ptr_Typ
) then
492 Actual
:= Make_Null
(Loc
);
495 Desig_Typ
:= Directly_Designated_Type
(Ptr_Typ
);
497 -- Check for a library-level access type whose designated type has
498 -- suppressed finalization or the access type is subject to pragma
499 -- No_Heap_Finalization. Such an access type lacks a master. Pass
500 -- a null actual to callee in order to signal a missing master.
502 if Is_Library_Level_Entity
(Ptr_Typ
)
503 and then (Finalize_Storage_Only
(Desig_Typ
)
504 or else No_Heap_Finalization
(Ptr_Typ
))
506 Actual
:= Make_Null
(Loc
);
508 -- Types in need of finalization actions
510 elsif Needs_Finalization
(Desig_Typ
) then
512 -- The general mechanism of creating finalization masters for
513 -- anonymous access types is disabled by default, otherwise
514 -- finalization masters will pop all over the place. Such types
515 -- use context-specific masters.
517 if Ekind
(Ptr_Typ
) = E_Anonymous_Access_Type
518 and then No
(Finalization_Master
(Ptr_Typ
))
520 Build_Anonymous_Master
(Ptr_Typ
);
523 -- Access-to-controlled types should always have a master
525 pragma Assert
(Present
(Finalization_Master
(Ptr_Typ
)));
528 Make_Attribute_Reference
(Loc
,
530 New_Occurrence_Of
(Finalization_Master
(Ptr_Typ
), Loc
),
531 Attribute_Name
=> Name_Unrestricted_Access
);
536 Actual
:= Make_Null
(Loc
);
540 Analyze_And_Resolve
(Actual
, Etype
(Formal
));
542 -- Build the parameter association for the new actual and add it to
543 -- the end of the function's actuals.
545 Add_Extra_Actual_To_Call
(Func_Call
, Formal
, Actual
);
547 end Add_Finalization_Master_Actual_To_Build_In_Place_Call
;
549 ------------------------------
550 -- Add_Extra_Actual_To_Call --
551 ------------------------------
553 procedure Add_Extra_Actual_To_Call
554 (Subprogram_Call
: Node_Id
;
555 Extra_Formal
: Entity_Id
;
556 Extra_Actual
: Node_Id
)
558 Loc
: constant Source_Ptr
:= Sloc
(Subprogram_Call
);
559 Param_Assoc
: Node_Id
;
563 Make_Parameter_Association
(Loc
,
564 Selector_Name
=> New_Occurrence_Of
(Extra_Formal
, Loc
),
565 Explicit_Actual_Parameter
=> Extra_Actual
);
567 Set_Parent
(Param_Assoc
, Subprogram_Call
);
568 Set_Parent
(Extra_Actual
, Param_Assoc
);
570 if Present
(Parameter_Associations
(Subprogram_Call
)) then
571 if Nkind
(Last
(Parameter_Associations
(Subprogram_Call
))) =
572 N_Parameter_Association
575 -- Find last named actual, and append
580 L
:= First_Actual
(Subprogram_Call
);
581 while Present
(L
) loop
582 if No
(Next_Actual
(L
)) then
583 Set_Next_Named_Actual
(Parent
(L
), Extra_Actual
);
591 Set_First_Named_Actual
(Subprogram_Call
, Extra_Actual
);
594 Append
(Param_Assoc
, To
=> Parameter_Associations
(Subprogram_Call
));
597 Set_Parameter_Associations
(Subprogram_Call
, New_List
(Param_Assoc
));
598 Set_First_Named_Actual
(Subprogram_Call
, Extra_Actual
);
600 end Add_Extra_Actual_To_Call
;
602 ---------------------------------------------
603 -- Add_Task_Actuals_To_Build_In_Place_Call --
604 ---------------------------------------------
606 procedure Add_Task_Actuals_To_Build_In_Place_Call
607 (Function_Call
: Node_Id
;
608 Function_Id
: Entity_Id
;
609 Master_Actual
: Node_Id
;
610 Chain
: Node_Id
:= Empty
)
612 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
614 Chain_Actual
: Node_Id
;
615 Chain_Formal
: Node_Id
;
616 Master_Formal
: Node_Id
;
619 -- No such extra parameters are needed if there are no tasks
621 if not Needs_BIP_Task_Actuals
(Function_Id
) then
625 Actual
:= Master_Actual
;
627 -- Use a dummy _master actual in case of No_Task_Hierarchy
629 if Restriction_Active
(No_Task_Hierarchy
) then
630 Actual
:= Make_Integer_Literal
(Loc
, Library_Task_Level
);
632 -- In the case where we use the master associated with an access type,
633 -- the actual is an entity and requires an explicit reference.
635 elsif Nkind
(Actual
) = N_Defining_Identifier
then
636 Actual
:= New_Occurrence_Of
(Actual
, Loc
);
639 -- Locate the implicit master parameter in the called function
641 Master_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Task_Master
);
642 Analyze_And_Resolve
(Actual
, Etype
(Master_Formal
));
644 -- Build the parameter association for the new actual and add it to the
645 -- end of the function's actuals.
647 Add_Extra_Actual_To_Call
(Function_Call
, Master_Formal
, Actual
);
649 -- Locate the implicit activation chain parameter in the called function
652 Build_In_Place_Formal
(Function_Id
, BIP_Activation_Chain
);
654 -- Create the actual which is a pointer to the current activation chain
656 if Restriction_Active
(No_Task_Hierarchy
) then
657 Chain_Actual
:= Make_Null
(Loc
);
659 elsif No
(Chain
) then
661 Make_Attribute_Reference
(Loc
,
662 Prefix
=> Make_Identifier
(Loc
, Name_uChain
),
663 Attribute_Name
=> Name_Unrestricted_Access
);
665 -- Allocator case; make a reference to the Chain passed in by the caller
669 Make_Attribute_Reference
(Loc
,
670 Prefix
=> New_Occurrence_Of
(Chain
, Loc
),
671 Attribute_Name
=> Name_Unrestricted_Access
);
674 Analyze_And_Resolve
(Chain_Actual
, Etype
(Chain_Formal
));
676 -- Build the parameter association for the new actual and add it to the
677 -- end of the function's actuals.
679 Add_Extra_Actual_To_Call
(Function_Call
, Chain_Formal
, Chain_Actual
);
680 end Add_Task_Actuals_To_Build_In_Place_Call
;
682 ----------------------------------
683 -- Apply_CW_Accessibility_Check --
684 ----------------------------------
686 procedure Apply_CW_Accessibility_Check
(Exp
: Node_Id
; Func
: Entity_Id
) is
687 Loc
: constant Source_Ptr
:= Sloc
(Exp
);
690 if Ada_Version
>= Ada_2005
691 and then Tagged_Type_Expansion
692 and then not Scope_Suppress
.Suppress
(Accessibility_Check
)
694 (Is_Class_Wide_Type
(Etype
(Exp
))
695 or else Nkind
(Exp
) in
696 N_Type_Conversion | N_Unchecked_Type_Conversion
697 or else (Is_Entity_Name
(Exp
)
698 and then Is_Formal
(Entity
(Exp
)))
699 or else Scope_Depth
(Enclosing_Dynamic_Scope
(Etype
(Exp
))) >
700 Scope_Depth
(Enclosing_Dynamic_Scope
(Func
)))
706 -- Ada 2005 (AI-251): In class-wide interface objects we displace
707 -- "this" to reference the base of the object. This is required to
708 -- get access to the TSD of the object.
710 if Is_Class_Wide_Type
(Etype
(Exp
))
711 and then Is_Interface
(Etype
(Exp
))
713 -- If the expression is an explicit dereference then we can
714 -- directly displace the pointer to reference the base of
717 if Nkind
(Exp
) = N_Explicit_Dereference
then
719 Make_Explicit_Dereference
(Loc
,
721 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
722 Make_Function_Call
(Loc
,
724 New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
725 Parameter_Associations
=> New_List
(
726 Unchecked_Convert_To
(RTE
(RE_Address
),
727 Duplicate_Subexpr
(Prefix
(Exp
)))))));
729 -- Similar case to the previous one but the expression is a
730 -- renaming of an explicit dereference.
732 elsif Nkind
(Exp
) = N_Identifier
733 and then Present
(Renamed_Object
(Entity
(Exp
)))
734 and then Nkind
(Renamed_Object
(Entity
(Exp
)))
735 = N_Explicit_Dereference
738 Make_Explicit_Dereference
(Loc
,
740 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
741 Make_Function_Call
(Loc
,
743 New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
744 Parameter_Associations
=> New_List
(
745 Unchecked_Convert_To
(RTE
(RE_Address
),
748 (Renamed_Object
(Entity
(Exp
)))))))));
750 -- Common case: obtain the address of the actual object and
751 -- displace the pointer to reference the base of the object.
755 Make_Explicit_Dereference
(Loc
,
757 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
758 Make_Function_Call
(Loc
,
760 New_Occurrence_Of
(RTE
(RE_Base_Address
), Loc
),
761 Parameter_Associations
=> New_List
(
762 Make_Attribute_Reference
(Loc
,
763 Prefix
=> Duplicate_Subexpr
(Exp
),
764 Attribute_Name
=> Name_Address
)))));
768 Make_Attribute_Reference
(Loc
,
769 Prefix
=> Duplicate_Subexpr
(Exp
),
770 Attribute_Name
=> Name_Tag
);
773 -- CodePeer does not do anything useful with
774 -- Ada.Tags.Type_Specific_Data components.
776 if not CodePeer_Mode
then
778 Make_Raise_Program_Error
(Loc
,
781 Left_Opnd
=> Build_Get_Access_Level
(Loc
, Tag_Node
),
783 Make_Integer_Literal
(Loc
,
784 Scope_Depth
(Enclosing_Dynamic_Scope
(Func
)))),
785 Reason
=> PE_Accessibility_Check_Failed
));
789 end Apply_CW_Accessibility_Check
;
791 -----------------------
792 -- BIP_Formal_Suffix --
793 -----------------------
795 function BIP_Formal_Suffix
(Kind
: BIP_Formal_Kind
) return String is
798 when BIP_Alloc_Form
=>
799 return BIP_Alloc_Suffix
;
801 when BIP_Storage_Pool
=>
802 return BIP_Storage_Pool_Suffix
;
804 when BIP_Finalization_Master
=>
805 return BIP_Finalization_Master_Suffix
;
807 when BIP_Task_Master
=>
808 return BIP_Task_Master_Suffix
;
810 when BIP_Activation_Chain
=>
811 return BIP_Activation_Chain_Suffix
;
813 when BIP_Object_Access
=>
814 return BIP_Object_Access_Suffix
;
816 end BIP_Formal_Suffix
;
818 ---------------------
819 -- BIP_Suffix_Kind --
820 ---------------------
822 function BIP_Suffix_Kind
(E
: Entity_Id
) return BIP_Formal_Kind
is
823 Nam
: constant String := Get_Name_String
(Chars
(E
));
825 function Has_Suffix
(Suffix
: String) return Boolean;
826 -- Return True if Nam has suffix Suffix
828 function Has_Suffix
(Suffix
: String) return Boolean is
829 Len
: constant Natural := Suffix
'Length;
831 return Nam
'Length > Len
832 and then Nam
(Nam
'Last - Len
+ 1 .. Nam
'Last) = Suffix
;
835 -- Start of processing for BIP_Suffix_Kind
838 if Has_Suffix
(BIP_Alloc_Suffix
) then
839 return BIP_Alloc_Form
;
841 elsif Has_Suffix
(BIP_Storage_Pool_Suffix
) then
842 return BIP_Storage_Pool
;
844 elsif Has_Suffix
(BIP_Finalization_Master_Suffix
) then
845 return BIP_Finalization_Master
;
847 elsif Has_Suffix
(BIP_Task_Master_Suffix
) then
848 return BIP_Task_Master
;
850 elsif Has_Suffix
(BIP_Activation_Chain_Suffix
) then
851 return BIP_Activation_Chain
;
853 elsif Has_Suffix
(BIP_Object_Access_Suffix
) then
854 return BIP_Object_Access
;
861 ---------------------------
862 -- Build_In_Place_Formal --
863 ---------------------------
865 function Build_In_Place_Formal
867 Kind
: BIP_Formal_Kind
) return Entity_Id
869 Extra_Formal
: Entity_Id
:= Extra_Formals
(Func
);
870 Formal_Suffix
: constant String := BIP_Formal_Suffix
(Kind
);
873 -- Maybe it would be better for each implicit formal of a build-in-place
874 -- function to have a flag or a Uint attribute to identify it. ???
876 -- The return type in the function declaration may have been a limited
877 -- view, and the extra formals for the function were not generated at
878 -- that point. At the point of call the full view must be available and
879 -- the extra formals can be created and Returns_By_Ref computed.
881 if No
(Extra_Formal
) then
882 Create_Extra_Formals
(Func
);
883 Extra_Formal
:= Extra_Formals
(Func
);
884 Compute_Returns_By_Ref
(Func
);
887 -- We search for a formal with a matching suffix. We can't search
888 -- for the full name, because of the code at the end of Sem_Ch6.-
889 -- Create_Extra_Formals, which copies the Extra_Formals over to
890 -- the Alias of an instance, which will cause the formals to have
891 -- "incorrect" names.
894 pragma Assert
(Present
(Extra_Formal
));
896 Name
: constant String := Get_Name_String
(Chars
(Extra_Formal
));
898 exit when Name
'Length >= Formal_Suffix
'Length
899 and then Formal_Suffix
=
900 Name
(Name
'Last - Formal_Suffix
'Length + 1 .. Name
'Last);
903 Next_Formal_With_Extras
(Extra_Formal
);
907 end Build_In_Place_Formal
;
909 -------------------------------
910 -- Build_Procedure_Body_Form --
911 -------------------------------
913 function Build_Procedure_Body_Form
914 (Func_Id
: Entity_Id
;
915 Func_Body
: Node_Id
) return Node_Id
917 Loc
: constant Source_Ptr
:= Sloc
(Func_Body
);
919 Proc_Decl
: constant Node_Id
:= Prev
(Unit_Declaration_Node
(Func_Id
));
920 -- It is assumed that the node before the declaration of the
921 -- corresponding subprogram spec is the declaration of the procedure
924 Proc_Id
: constant Entity_Id
:= Defining_Entity
(Proc_Decl
);
926 procedure Replace_Returns
(Param_Id
: Entity_Id
; Stmts
: List_Id
);
927 -- Replace each return statement found in the list Stmts with an
928 -- assignment of the return expression to parameter Param_Id.
930 ---------------------
931 -- Replace_Returns --
932 ---------------------
934 procedure Replace_Returns
(Param_Id
: Entity_Id
; Stmts
: List_Id
) is
938 Stmt
:= First
(Stmts
);
939 while Present
(Stmt
) loop
940 if Nkind
(Stmt
) = N_Block_Statement
then
941 Replace_Returns
(Param_Id
,
942 Statements
(Handled_Statement_Sequence
(Stmt
)));
944 elsif Nkind
(Stmt
) = N_Case_Statement
then
948 Alt
:= First
(Alternatives
(Stmt
));
949 while Present
(Alt
) loop
950 Replace_Returns
(Param_Id
, Statements
(Alt
));
955 elsif Nkind
(Stmt
) = N_Extended_Return_Statement
then
957 Ret_Obj
: constant Entity_Id
:=
959 (First
(Return_Object_Declarations
(Stmt
)));
960 Assign
: constant Node_Id
:=
961 Make_Assignment_Statement
(Sloc
(Stmt
),
963 New_Occurrence_Of
(Param_Id
, Loc
),
965 New_Occurrence_Of
(Ret_Obj
, Sloc
(Stmt
)));
969 -- The extended return may just contain the declaration
971 if Present
(Handled_Statement_Sequence
(Stmt
)) then
972 Stmts
:= Statements
(Handled_Statement_Sequence
(Stmt
));
977 Set_Assignment_OK
(Name
(Assign
));
980 Make_Block_Statement
(Sloc
(Stmt
),
982 Return_Object_Declarations
(Stmt
),
983 Handled_Statement_Sequence
=>
984 Make_Handled_Sequence_Of_Statements
(Loc
,
985 Statements
=> Stmts
)));
987 Replace_Returns
(Param_Id
, Stmts
);
989 Append_To
(Stmts
, Assign
);
990 Append_To
(Stmts
, Make_Simple_Return_Statement
(Loc
));
993 elsif Nkind
(Stmt
) = N_If_Statement
then
994 Replace_Returns
(Param_Id
, Then_Statements
(Stmt
));
995 Replace_Returns
(Param_Id
, Else_Statements
(Stmt
));
1000 Part
:= First
(Elsif_Parts
(Stmt
));
1001 while Present
(Part
) loop
1002 Replace_Returns
(Param_Id
, Then_Statements
(Part
));
1007 elsif Nkind
(Stmt
) = N_Loop_Statement
then
1008 Replace_Returns
(Param_Id
, Statements
(Stmt
));
1010 elsif Nkind
(Stmt
) = N_Simple_Return_Statement
then
1017 Make_Assignment_Statement
(Sloc
(Stmt
),
1018 Name
=> New_Occurrence_Of
(Param_Id
, Loc
),
1019 Expression
=> Relocate_Node
(Expression
(Stmt
))));
1021 Insert_After
(Stmt
, Make_Simple_Return_Statement
(Loc
));
1023 -- Skip the added return
1030 end Replace_Returns
;
1037 -- Start of processing for Build_Procedure_Body_Form
1040 -- This routine replaces the original function body:
1042 -- function F (...) return Array_Typ is
1045 -- return Something;
1048 -- with the following:
1050 -- procedure P (..., Result : out Array_Typ) is
1053 -- Result := Something;
1057 Statements
(Handled_Statement_Sequence
(Func_Body
));
1058 Replace_Returns
(Last_Entity
(Proc_Id
), Stmts
);
1061 Make_Subprogram_Body
(Loc
,
1063 Copy_Subprogram_Spec
(Specification
(Proc_Decl
)),
1064 Declarations
=> Declarations
(Func_Body
),
1065 Handled_Statement_Sequence
=>
1066 Make_Handled_Sequence_Of_Statements
(Loc
,
1067 Statements
=> Stmts
));
1069 -- If the function is a generic instance, so is the new procedure.
1070 -- Set flag accordingly so that the proper renaming declarations are
1073 Set_Is_Generic_Instance
(Proc_Id
, Is_Generic_Instance
(Func_Id
));
1075 end Build_Procedure_Body_Form
;
1077 -----------------------
1078 -- Caller_Known_Size --
1079 -----------------------
1081 function Caller_Known_Size
1082 (Func_Call
: Node_Id
;
1083 Result_Subt
: Entity_Id
) return Boolean
1085 Utyp
: constant Entity_Id
:= Underlying_Type
(Result_Subt
);
1088 return not Needs_Secondary_Stack
(Utyp
)
1089 and then not (Is_Tagged_Type
(Utyp
)
1090 and then Present
(Controlling_Argument
(Func_Call
)));
1091 end Caller_Known_Size
;
1093 -----------------------
1094 -- Check_BIP_Actuals --
1095 -----------------------
1097 function Check_BIP_Actuals
1098 (Subp_Call
: Node_Id
;
1099 Subp_Id
: Entity_Id
) return Boolean
1105 pragma Assert
(Nkind
(Subp_Call
) in N_Entry_Call_Statement
1107 | N_Procedure_Call_Statement
);
1109 -- In CodePeer_Mode, the tree for `'Elab_Spec` procedures will be
1110 -- malformed because GNAT does not perform the usual expansion that
1111 -- results in the importation of external elaboration procedure symbols.
1112 -- This is expected: the CodePeer backend has special handling for this
1114 -- Thus, we do not need to check the tree (and in fact can't, because
1118 and then Nkind
(Name
(Subp_Call
)) = N_Attribute_Reference
1119 and then Attribute_Name
(Name
(Subp_Call
)) in Name_Elab_Spec
1121 | Name_Elab_Subp_Body
1126 Formal
:= First_Formal_With_Extras
(Subp_Id
);
1127 Actual
:= First_Actual
(Subp_Call
);
1129 while Present
(Formal
) and then Present
(Actual
) loop
1130 if Is_Build_In_Place_Entity
(Formal
)
1131 and then Nkind
(Actual
) = N_Identifier
1132 and then Is_Build_In_Place_Entity
(Entity
(Actual
))
1133 and then BIP_Suffix_Kind
(Formal
)
1134 /= BIP_Suffix_Kind
(Entity
(Actual
))
1139 Next_Formal_With_Extras
(Formal
);
1140 Next_Actual
(Actual
);
1143 return No
(Formal
) and then No
(Actual
);
1144 end Check_BIP_Actuals
;
1146 -----------------------------
1147 -- Check_Number_Of_Actuals --
1148 -----------------------------
1150 function Check_Number_Of_Actuals
1151 (Subp_Call
: Node_Id
;
1152 Subp_Id
: Entity_Id
) return Boolean
1158 pragma Assert
(Nkind
(Subp_Call
) in N_Entry_Call_Statement
1160 | N_Procedure_Call_Statement
);
1162 Formal
:= First_Formal_With_Extras
(Subp_Id
);
1163 Actual
:= First_Actual
(Subp_Call
);
1165 while Present
(Formal
) and then Present
(Actual
) loop
1166 Next_Formal_With_Extras
(Formal
);
1167 Next_Actual
(Actual
);
1170 return No
(Formal
) and then No
(Actual
);
1171 end Check_Number_Of_Actuals
;
1173 --------------------------------
1174 -- Check_Overriding_Operation --
1175 --------------------------------
1177 procedure Check_Overriding_Operation
(Subp
: Entity_Id
) is
1178 Typ
: constant Entity_Id
:= Find_Dispatching_Type
(Subp
);
1179 Op_List
: constant Elist_Id
:= Primitive_Operations
(Typ
);
1181 Prim_Op
: Entity_Id
;
1185 if Is_Derived_Type
(Typ
)
1186 and then not Is_Private_Type
(Typ
)
1187 and then In_Open_Scopes
(Scope
(Etype
(Typ
)))
1188 and then Is_Base_Type
(Typ
)
1190 -- Subp overrides an inherited private operation if there is an
1191 -- inherited operation with a different name than Subp (see
1192 -- Derive_Subprogram) whose Alias is a hidden subprogram with the
1193 -- same name as Subp.
1195 Op_Elmt
:= First_Elmt
(Op_List
);
1196 while Present
(Op_Elmt
) loop
1197 Prim_Op
:= Node
(Op_Elmt
);
1198 Par_Op
:= Alias
(Prim_Op
);
1201 and then not Comes_From_Source
(Prim_Op
)
1202 and then Chars
(Prim_Op
) /= Chars
(Par_Op
)
1203 and then Chars
(Par_Op
) = Chars
(Subp
)
1204 and then Is_Hidden
(Par_Op
)
1205 and then Type_Conformant
(Prim_Op
, Subp
)
1207 Set_DT_Position_Value
(Subp
, DT_Position
(Prim_Op
));
1210 Next_Elmt
(Op_Elmt
);
1213 end Check_Overriding_Operation
;
1215 -------------------------------
1216 -- Detect_Infinite_Recursion --
1217 -------------------------------
1219 procedure Detect_Infinite_Recursion
(N
: Node_Id
; Spec
: Entity_Id
) is
1220 Loc
: constant Source_Ptr
:= Sloc
(N
);
1222 Var_List
: constant Elist_Id
:= New_Elmt_List
;
1223 -- List of globals referenced by body of procedure
1225 Call_List
: constant Elist_Id
:= New_Elmt_List
;
1226 -- List of recursive calls in body of procedure
1228 Shad_List
: constant Elist_Id
:= New_Elmt_List
;
1229 -- List of entity id's for entities created to capture the value of
1230 -- referenced globals on entry to the procedure.
1232 Scop
: constant Uint
:= Scope_Depth
(Spec
);
1233 -- This is used to record the scope depth of the current procedure, so
1234 -- that we can identify global references.
1236 Max_Vars
: constant := 4;
1237 -- Do not test more than four global variables
1239 Count_Vars
: Natural := 0;
1240 -- Count variables found so far
1252 function Process
(Nod
: Node_Id
) return Traverse_Result
;
1253 -- Function to traverse the subprogram body (using Traverse_Func)
1259 function Process
(Nod
: Node_Id
) return Traverse_Result
is
1263 if Nkind
(Nod
) = N_Procedure_Call_Statement
then
1265 -- Case of one of the detected recursive calls
1267 if Is_Entity_Name
(Name
(Nod
))
1268 and then Has_Recursive_Call
(Entity
(Name
(Nod
)))
1269 and then Entity
(Name
(Nod
)) = Spec
1271 Append_Elmt
(Nod
, Call_List
);
1274 -- Any other procedure call may have side effects
1280 -- A call to a pure function can always be ignored
1282 elsif Nkind
(Nod
) = N_Function_Call
1283 and then Is_Entity_Name
(Name
(Nod
))
1284 and then Is_Pure
(Entity
(Name
(Nod
)))
1288 -- Case of an identifier reference
1290 elsif Nkind
(Nod
) = N_Identifier
then
1291 Ent
:= Entity
(Nod
);
1293 -- If no entity, then ignore the reference
1295 -- Not clear why this can happen. To investigate, remove this
1296 -- test and look at the crash that occurs here in 3401-004 ???
1301 -- Ignore entities with no Scope, again not clear how this
1302 -- can happen, to investigate, look at 4108-008 ???
1304 elsif No
(Scope
(Ent
)) then
1307 -- Ignore the reference if not to a more global object
1309 elsif Scope_Depth
(Scope
(Ent
)) >= Scop
then
1312 -- References to types, exceptions and constants are always OK
1315 or else Ekind
(Ent
) = E_Exception
1316 or else Ekind
(Ent
) = E_Constant
1320 -- If other than a non-volatile scalar variable, we have some
1321 -- kind of global reference (e.g. to a function) that we cannot
1322 -- deal with so we forget the attempt.
1324 elsif Ekind
(Ent
) /= E_Variable
1325 or else not Is_Scalar_Type
(Etype
(Ent
))
1326 or else Treat_As_Volatile
(Ent
)
1330 -- Otherwise we have a reference to a global scalar
1333 -- Loop through global entities already detected
1335 Elm
:= First_Elmt
(Var_List
);
1337 -- If not detected before, record this new global reference
1340 Count_Vars
:= Count_Vars
+ 1;
1342 if Count_Vars
<= Max_Vars
then
1343 Append_Elmt
(Entity
(Nod
), Var_List
);
1350 -- If recorded before, ignore
1352 elsif Node
(Elm
) = Entity
(Nod
) then
1355 -- Otherwise keep looking
1365 -- For all other node kinds, recursively visit syntactic children
1372 function Traverse_Body
is new Traverse_Func
(Process
);
1374 -- Start of processing for Detect_Infinite_Recursion
1377 -- Do not attempt detection in No_Implicit_Conditional mode, since we
1378 -- won't be able to generate the code to handle the recursion in any
1381 if Restriction_Active
(No_Implicit_Conditionals
) then
1385 -- Otherwise do traversal and quit if we get abandon signal
1387 if Traverse_Body
(N
) = Abandon
then
1390 -- We must have a call, since Has_Recursive_Call was set. If not just
1391 -- ignore (this is only an error check, so if we have a funny situation,
1392 -- due to bugs or errors, we do not want to bomb).
1394 elsif Is_Empty_Elmt_List
(Call_List
) then
1398 -- Here is the case where we detect recursion at compile time
1400 -- Push our current scope for analyzing the declarations and code that
1401 -- we will insert for the checking.
1405 -- This loop builds temporary variables for each of the referenced
1406 -- globals, so that at the end of the loop the list Shad_List contains
1407 -- these temporaries in one-to-one correspondence with the elements in
1411 Elm
:= First_Elmt
(Var_List
);
1412 while Present
(Elm
) loop
1414 Ent
:= Make_Temporary
(Loc
, 'S');
1415 Append_Elmt
(Ent
, Shad_List
);
1417 -- Insert a declaration for this temporary at the start of the
1418 -- declarations for the procedure. The temporaries are declared as
1419 -- constant objects initialized to the current values of the
1420 -- corresponding temporaries.
1423 Make_Object_Declaration
(Loc
,
1424 Defining_Identifier
=> Ent
,
1425 Object_Definition
=> New_Occurrence_Of
(Etype
(Var
), Loc
),
1426 Constant_Present
=> True,
1427 Expression
=> New_Occurrence_Of
(Var
, Loc
));
1430 Prepend
(Decl
, Declarations
(N
));
1432 Insert_After
(Last
, Decl
);
1440 -- Loop through calls
1442 Call
:= First_Elmt
(Call_List
);
1443 while Present
(Call
) loop
1445 -- Build a predicate expression of the form
1448 -- and then global1 = temp1
1449 -- and then global2 = temp2
1452 -- This predicate determines if any of the global values
1453 -- referenced by the procedure have changed since the
1454 -- current call, if not an infinite recursion is assured.
1456 Test
:= New_Occurrence_Of
(Standard_True
, Loc
);
1458 Elm1
:= First_Elmt
(Var_List
);
1459 Elm2
:= First_Elmt
(Shad_List
);
1460 while Present
(Elm1
) loop
1466 Left_Opnd
=> New_Occurrence_Of
(Node
(Elm1
), Loc
),
1467 Right_Opnd
=> New_Occurrence_Of
(Node
(Elm2
), Loc
)));
1473 -- Now we replace the call with the sequence
1475 -- if no-changes (see above) then
1476 -- raise Storage_Error;
1481 Rewrite
(Node
(Call
),
1482 Make_If_Statement
(Loc
,
1484 Then_Statements
=> New_List
(
1485 Make_Raise_Storage_Error
(Loc
,
1486 Reason
=> SE_Infinite_Recursion
)),
1488 Else_Statements
=> New_List
(
1489 Relocate_Node
(Node
(Call
)))));
1491 Analyze
(Node
(Call
));
1496 -- Remove temporary scope stack entry used for analysis
1499 end Detect_Infinite_Recursion
;
1501 --------------------
1502 -- Expand_Actuals --
1503 --------------------
1505 procedure Expand_Actuals
1508 Post_Call
: out List_Id
)
1510 Loc
: constant Source_Ptr
:= Sloc
(N
);
1514 E_Actual
: Entity_Id
;
1515 E_Formal
: Entity_Id
;
1517 procedure Add_Call_By_Copy_Code
;
1518 -- For cases where the parameter must be passed by copy, this routine
1519 -- generates a temporary variable into which the actual is copied and
1520 -- then passes this as the parameter. For an OUT or IN OUT parameter,
1521 -- an assignment is also generated to copy the result back. The call
1522 -- also takes care of any constraint checks required for the type
1523 -- conversion case (on both the way in and the way out).
1525 procedure Add_Simple_Call_By_Copy_Code
(Force
: Boolean);
1526 -- This is similar to the above, but is used in cases where we know
1527 -- that all that is needed is to simply create a temporary and copy
1528 -- the value in and out of the temporary. If Force is True, then the
1529 -- procedure may disregard legality considerations.
1531 -- ??? We need to do the copy for a bit-packed array because this is
1532 -- where the rewriting into a mask-and-shift sequence is done. But of
1533 -- course this may break the program if it expects bits to be really
1534 -- passed by reference. That's what we have done historically though.
1536 procedure Add_Validation_Call_By_Copy_Code
(Act
: Node_Id
);
1537 -- Perform copy-back for actual parameter Act which denotes a validation
1540 procedure Check_Fortran_Logical
;
1541 -- A value of type Logical that is passed through a formal parameter
1542 -- must be normalized because .TRUE. usually does not have the same
1543 -- representation as True. We assume that .FALSE. = False = 0.
1544 -- What about functions that return a logical type ???
1546 function Is_Legal_Copy
return Boolean;
1547 -- Check that an actual can be copied before generating the temporary
1548 -- to be used in the call. If the formal is of a by_reference type or
1549 -- is aliased, then the program is illegal (this can only happen in
1550 -- the presence of representation clauses that force a misalignment)
1551 -- If the formal is a by_reference parameter imposed by a DEC pragma,
1552 -- emit a warning that this might lead to unaligned arguments.
1554 function Make_Var
(Actual
: Node_Id
) return Entity_Id
;
1555 -- Returns an entity that refers to the given actual parameter, Actual
1556 -- (not including any type conversion). If Actual is an entity name,
1557 -- then this entity is returned unchanged, otherwise a renaming is
1558 -- created to provide an entity for the actual.
1560 procedure Reset_Packed_Prefix
;
1561 -- The expansion of a packed array component reference is delayed in
1562 -- the context of a call. Now we need to complete the expansion, so we
1563 -- unmark the analyzed bits in all prefixes.
1565 function Requires_Atomic_Or_Volatile_Copy
return Boolean;
1566 -- Returns whether a copy is required as per RM C.6(19) and gives a
1567 -- warning in this case.
1569 ---------------------------
1570 -- Add_Call_By_Copy_Code --
1571 ---------------------------
1573 procedure Add_Call_By_Copy_Code
is
1576 F_Typ
: Entity_Id
:= Etype
(Formal
);
1584 if not Is_Legal_Copy
then
1588 Temp
:= Make_Temporary
(Loc
, 'T', Actual
);
1590 -- Handle formals whose type comes from the limited view
1592 if From_Limited_With
(F_Typ
)
1593 and then Has_Non_Limited_View
(F_Typ
)
1595 F_Typ
:= Non_Limited_View
(F_Typ
);
1598 -- Use formal type for temp, unless formal type is an unconstrained
1599 -- array, in which case we don't have to worry about bounds checks,
1600 -- and we use the actual type, since that has appropriate bounds.
1602 if Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
) then
1603 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1605 Indic
:= New_Occurrence_Of
(F_Typ
, Loc
);
1608 -- The new code will be properly analyzed below and the setting of
1609 -- the Do_Range_Check flag recomputed so remove the obsolete one.
1611 Set_Do_Range_Check
(Actual
, False);
1613 if Nkind
(Actual
) = N_Type_Conversion
then
1614 Set_Do_Range_Check
(Expression
(Actual
), False);
1616 V_Typ
:= Etype
(Expression
(Actual
));
1618 -- If the formal is an (in-)out parameter, capture the name
1619 -- of the variable in order to build the post-call assignment.
1621 Var
:= Make_Var
(Expression
(Actual
));
1623 Crep
:= not Has_Compatible_Representation
1624 (Target_Typ
=> F_Typ
,
1625 Operand_Typ
=> Etype
(Expression
(Actual
)));
1628 V_Typ
:= Etype
(Actual
);
1629 Var
:= Make_Var
(Actual
);
1633 -- If the actual denotes a variable which captures the value of an
1634 -- object for validation purposes, we propagate the link with this
1635 -- object to the new variable made from the actual just above.
1637 if Ekind
(Formal
) /= E_In_Parameter
1638 and then Is_Validation_Variable_Reference
(Actual
)
1641 Ref
: constant Node_Id
:= Unqual_Conv
(Actual
);
1644 if Is_Entity_Name
(Ref
) then
1645 Set_Validated_Object
(Var
, Validated_Object
(Entity
(Ref
)));
1648 pragma Assert
(False);
1654 -- Setup initialization for case of in out parameter, or an out
1655 -- parameter where the formal is an unconstrained array (in the
1656 -- latter case, we have to pass in an object with bounds).
1658 -- If this is an out parameter, the initial copy is wasteful, so as
1659 -- an optimization for the one-dimensional case we extract the
1660 -- bounds of the actual and build an uninitialized temporary of the
1663 -- If the formal is an out parameter with discriminants, the
1664 -- discriminants must be captured even if the rest of the object
1665 -- is in principle uninitialized, because the discriminants may
1666 -- be read by the called subprogram.
1668 if Ekind
(Formal
) = E_In_Out_Parameter
1669 or else (Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
))
1670 or else Has_Discriminants
(F_Typ
)
1672 if Nkind
(Actual
) = N_Type_Conversion
then
1673 if Conversion_OK
(Actual
) then
1674 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1676 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1679 elsif Ekind
(Formal
) = E_Out_Parameter
1680 and then Is_Array_Type
(F_Typ
)
1681 and then Number_Dimensions
(F_Typ
) = 1
1682 and then not Has_Non_Null_Base_Init_Proc
(F_Typ
)
1684 -- Actual is a one-dimensional array or slice, and the type
1685 -- requires no initialization. Create a temporary of the
1686 -- right size, but do not copy actual into it (optimization).
1690 Make_Subtype_Indication
(Loc
,
1691 Subtype_Mark
=> New_Occurrence_Of
(F_Typ
, Loc
),
1693 Make_Index_Or_Discriminant_Constraint
(Loc
,
1694 Constraints
=> New_List
(
1697 Make_Attribute_Reference
(Loc
,
1698 Prefix
=> New_Occurrence_Of
(Var
, Loc
),
1699 Attribute_Name
=> Name_First
),
1701 Make_Attribute_Reference
(Loc
,
1702 Prefix
=> New_Occurrence_Of
(Var
, Loc
),
1703 Attribute_Name
=> Name_Last
)))));
1706 Init
:= New_Occurrence_Of
(Var
, Loc
);
1709 -- An initialization is created for packed conversions as
1710 -- actuals for out parameters to enable Make_Object_Declaration
1711 -- to determine the proper subtype for N_Node. Note that this
1712 -- is wasteful because the extra copying on the call side is
1713 -- not required for such out parameters. ???
1715 elsif Ekind
(Formal
) = E_Out_Parameter
1716 and then Nkind
(Actual
) = N_Type_Conversion
1717 and then (Is_Bit_Packed_Array
(F_Typ
)
1719 Is_Bit_Packed_Array
(Etype
(Expression
(Actual
))))
1721 if Conversion_OK
(Actual
) then
1722 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1724 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1727 elsif Ekind
(Formal
) = E_In_Parameter
then
1729 -- Handle the case in which the actual is a type conversion
1731 if Nkind
(Actual
) = N_Type_Conversion
then
1732 if Conversion_OK
(Actual
) then
1733 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1735 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1738 Init
:= New_Occurrence_Of
(Var
, Loc
);
1741 -- Access types are passed in without checks, but if a copy-back is
1742 -- required for a null-excluding check on an in-out or out parameter,
1743 -- then the initial value is that of the actual.
1745 elsif Is_Access_Type
(E_Formal
)
1746 and then Can_Never_Be_Null
(Etype
(Actual
))
1747 and then not Can_Never_Be_Null
(E_Formal
)
1749 Init
:= New_Occurrence_Of
(Var
, Loc
);
1751 -- View conversions when the formal type has the Default_Value aspect
1752 -- require passing in the value of the conversion's operand. The type
1753 -- of that operand also has Default_Value, as required by AI12-0074
1754 -- (RM 6.4.1(5.3/4)). The subtype denoted by the subtype_indication
1755 -- is changed to the base type of the formal subtype, to ensure that
1756 -- the actual's value can be assigned without a constraint check
1757 -- (note that no check is done on passing to an out parameter). Also
1758 -- note that the two types necessarily share the same ancestor type,
1759 -- as required by 6.4.1(5.2/4), so underlying base types will match.
1761 elsif Ekind
(Formal
) = E_Out_Parameter
1762 and then Is_Scalar_Type
(Etype
(F_Typ
))
1763 and then Nkind
(Actual
) = N_Type_Conversion
1764 and then Present
(Default_Aspect_Value
(Etype
(F_Typ
)))
1766 Indic
:= New_Occurrence_Of
(Base_Type
(F_Typ
), Loc
);
1768 (Base_Type
(F_Typ
), New_Occurrence_Of
(Var
, Loc
));
1775 Make_Object_Declaration
(Loc
,
1776 Defining_Identifier
=> Temp
,
1777 Object_Definition
=> Indic
,
1778 Expression
=> Init
);
1779 Set_Assignment_OK
(N_Node
);
1780 Insert_Action
(N
, N_Node
);
1782 -- Now, normally the deal here is that we use the defining
1783 -- identifier created by that object declaration. There is
1784 -- one exception to this. In the change of representation case
1785 -- the above declaration will end up looking like:
1787 -- temp : type := identifier;
1789 -- And in this case we might as well use the identifier directly
1790 -- and eliminate the temporary. Note that the analysis of the
1791 -- declaration was not a waste of time in that case, since it is
1792 -- what generated the necessary change of representation code. If
1793 -- the change of representation introduced additional code, as in
1794 -- a fixed-integer conversion, the expression is not an identifier
1795 -- and must be kept.
1798 and then Present
(Expression
(N_Node
))
1799 and then Is_Entity_Name
(Expression
(N_Node
))
1801 Temp
:= Entity
(Expression
(N_Node
));
1802 Rewrite
(N_Node
, Make_Null_Statement
(Loc
));
1805 -- For IN parameter, all we do is to replace the actual
1807 if Ekind
(Formal
) = E_In_Parameter
then
1808 Rewrite
(Actual
, New_Occurrence_Of
(Temp
, Loc
));
1811 -- Processing for OUT or IN OUT parameter
1814 -- Kill current value indications for the temporary variable we
1815 -- created, since we just passed it as an OUT parameter.
1817 Kill_Current_Values
(Temp
);
1818 Set_Is_Known_Valid
(Temp
, False);
1819 Set_Is_True_Constant
(Temp
, False);
1821 -- If type conversion, use reverse conversion on exit
1823 if Nkind
(Actual
) = N_Type_Conversion
then
1824 if Conversion_OK
(Actual
) then
1825 Expr
:= OK_Convert_To
(V_Typ
, New_Occurrence_Of
(Temp
, Loc
));
1827 Expr
:= Convert_To
(V_Typ
, New_Occurrence_Of
(Temp
, Loc
));
1830 Expr
:= New_Occurrence_Of
(Temp
, Loc
);
1833 Rewrite
(Actual
, New_Occurrence_Of
(Temp
, Sloc
(Actual
)));
1836 -- If the actual is a conversion of a packed reference, it may
1837 -- already have been expanded by Remove_Side_Effects, and the
1838 -- resulting variable is a temporary which does not designate
1839 -- the proper out-parameter, which may not be addressable. In
1840 -- that case, generate an assignment to the original expression
1841 -- (before expansion of the packed reference) so that the proper
1842 -- expansion of assignment to a packed component can take place.
1849 if Is_Renaming_Of_Object
(Var
)
1850 and then Nkind
(Renamed_Object
(Var
)) = N_Selected_Component
1851 and then Nkind
(Original_Node
(Prefix
(Renamed_Object
(Var
))))
1852 = N_Indexed_Component
1854 Has_Non_Standard_Rep
(Etype
(Prefix
(Renamed_Object
(Var
))))
1856 Obj
:= Renamed_Object
(Var
);
1858 Make_Selected_Component
(Loc
,
1860 New_Copy_Tree
(Original_Node
(Prefix
(Obj
))),
1861 Selector_Name
=> New_Copy
(Selector_Name
(Obj
)));
1862 Reset_Analyzed_Flags
(Lhs
);
1865 Lhs
:= New_Occurrence_Of
(Var
, Loc
);
1868 Set_Assignment_OK
(Lhs
);
1870 if Is_Access_Type
(E_Formal
)
1871 and then Is_Entity_Name
(Lhs
)
1873 Present
(Effective_Extra_Accessibility
(Entity
(Lhs
)))
1874 and then not No_Dynamic_Accessibility_Checks_Enabled
(Lhs
)
1876 -- Copyback target is an Ada 2012 stand-alone object of an
1877 -- anonymous access type.
1879 pragma Assert
(Ada_Version
>= Ada_2012
);
1881 Apply_Accessibility_Check
(Lhs
, E_Formal
, N
);
1883 Append_To
(Post_Call
,
1884 Make_Assignment_Statement
(Loc
,
1886 Expression
=> Expr
));
1888 -- We would like to somehow suppress generation of the
1889 -- extra_accessibility assignment generated by the expansion
1890 -- of the above assignment statement. It's not a correctness
1891 -- issue because the following assignment renders it dead,
1892 -- but generating back-to-back assignments to the same
1893 -- target is undesirable. ???
1895 Append_To
(Post_Call
,
1896 Make_Assignment_Statement
(Loc
,
1897 Name
=> New_Occurrence_Of
(
1898 Effective_Extra_Accessibility
(Entity
(Lhs
)), Loc
),
1899 Expression
=> Make_Integer_Literal
(Loc
,
1900 Type_Access_Level
(E_Formal
))));
1903 if Is_Access_Type
(E_Formal
)
1904 and then Can_Never_Be_Null
(Etype
(Actual
))
1905 and then not Can_Never_Be_Null
(E_Formal
)
1907 Append_To
(Post_Call
,
1908 Make_Raise_Constraint_Error
(Loc
,
1911 Left_Opnd
=> New_Occurrence_Of
(Temp
, Loc
),
1912 Right_Opnd
=> Make_Null
(Loc
)),
1913 Reason
=> CE_Access_Check_Failed
));
1916 Append_To
(Post_Call
,
1917 Make_Assignment_Statement
(Loc
,
1919 Expression
=> Expr
));
1922 -- Add a copy-back to reflect any potential changes in value
1923 -- back into the original object, if any.
1925 if Is_Validation_Variable_Reference
(Lhs
) then
1926 Add_Validation_Call_By_Copy_Code
(Lhs
);
1930 end Add_Call_By_Copy_Code
;
1932 ----------------------------------
1933 -- Add_Simple_Call_By_Copy_Code --
1934 ----------------------------------
1936 procedure Add_Simple_Call_By_Copy_Code
(Force
: Boolean) is
1938 F_Typ
: Entity_Id
:= Etype
(Formal
);
1947 -- Unless forced not to, check the legality of the copy operation
1949 if not Force
and then not Is_Legal_Copy
then
1953 -- Handle formals whose type comes from the limited view
1955 if From_Limited_With
(F_Typ
)
1956 and then Has_Non_Limited_View
(F_Typ
)
1958 F_Typ
:= Non_Limited_View
(F_Typ
);
1961 -- Use formal type for temp, unless formal type is an unconstrained
1962 -- array, in which case we don't have to worry about bounds checks,
1963 -- and we use the actual type, since that has appropriate bounds.
1965 if Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
) then
1966 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1968 Indic
:= New_Occurrence_Of
(F_Typ
, Loc
);
1971 -- Prepare to generate code
1973 Reset_Packed_Prefix
;
1975 Temp
:= Make_Temporary
(Loc
, 'T', Actual
);
1976 Incod
:= Relocate_Node
(Actual
);
1977 Outcod
:= New_Copy_Tree
(Incod
);
1979 -- Generate declaration of temporary variable, initializing it
1980 -- with the input parameter unless we have an OUT formal or
1981 -- this is an initialization call.
1983 -- If the formal is an out parameter with discriminants, the
1984 -- discriminants must be captured even if the rest of the object
1985 -- is in principle uninitialized, because the discriminants may
1986 -- be read by the called subprogram.
1988 if Ekind
(Formal
) = E_Out_Parameter
then
1991 if Has_Discriminants
(F_Typ
) then
1992 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1995 elsif Inside_Init_Proc
then
1997 -- Skip using the actual as the expression in Decl if we are in
1998 -- an init proc and it is not a component which depends on a
1999 -- discriminant, because, in this case, we need to use the actual
2000 -- type of the component instead.
2002 if Nkind
(Actual
) /= N_Selected_Component
2004 not Has_Discriminant_Dependent_Constraint
2005 (Entity
(Selector_Name
(Actual
)))
2009 -- Otherwise, keep the component so we can generate the proper
2010 -- actual subtype - since the subtype depends on enclosing
2019 Make_Object_Declaration
(Loc
,
2020 Defining_Identifier
=> Temp
,
2021 Object_Definition
=> Indic
,
2022 Expression
=> Incod
);
2027 -- If the call is to initialize a component of a composite type,
2028 -- and the component does not depend on discriminants, use the
2029 -- actual type of the component. This is required in case the
2030 -- component is constrained, because in general the formal of the
2031 -- initialization procedure will be unconstrained. Note that if
2032 -- the component being initialized is constrained by an enclosing
2033 -- discriminant, the presence of the initialization in the
2034 -- declaration will generate an expression for the actual subtype.
2036 Set_No_Initialization
(Decl
);
2037 Set_Object_Definition
(Decl
,
2038 New_Occurrence_Of
(Etype
(Actual
), Loc
));
2041 Insert_Action
(N
, Decl
);
2043 -- The actual is simply a reference to the temporary
2045 Rewrite
(Actual
, New_Occurrence_Of
(Temp
, Loc
));
2047 -- Generate copy out if OUT or IN OUT parameter
2049 if Ekind
(Formal
) /= E_In_Parameter
then
2051 Rhs
:= New_Occurrence_Of
(Temp
, Loc
);
2052 Set_Is_True_Constant
(Temp
, False);
2054 -- Deal with conversion
2056 if Nkind
(Lhs
) = N_Type_Conversion
then
2057 Lhs
:= Expression
(Lhs
);
2058 Rhs
:= Convert_To
(Etype
(Actual
), Rhs
);
2061 Append_To
(Post_Call
,
2062 Make_Assignment_Statement
(Loc
,
2064 Expression
=> Rhs
));
2065 Set_Assignment_OK
(Name
(Last
(Post_Call
)));
2067 end Add_Simple_Call_By_Copy_Code
;
2069 --------------------------------------
2070 -- Add_Validation_Call_By_Copy_Code --
2071 --------------------------------------
2073 procedure Add_Validation_Call_By_Copy_Code
(Act
: Node_Id
) is
2074 Var
: constant Node_Id
:= Unqual_Conv
(Act
);
2078 Obj_Typ
: Entity_Id
;
2082 -- Generate range check if required
2084 if Do_Range_Check
(Actual
) then
2085 Generate_Range_Check
(Actual
, E_Formal
, CE_Range_Check_Failed
);
2088 -- If there is a type conversion in the actual, it will be reinstated
2089 -- below, the new instance will be properly analyzed and the setting
2090 -- of the Do_Range_Check flag recomputed so remove the obsolete one.
2092 if Nkind
(Actual
) = N_Type_Conversion
then
2093 Set_Do_Range_Check
(Expression
(Actual
), False);
2096 -- Copy the value of the validation variable back into the object
2099 if Is_Entity_Name
(Var
) then
2100 Var_Id
:= Entity
(Var
);
2101 Obj
:= Validated_Object
(Var_Id
);
2102 Obj_Typ
:= Etype
(Obj
);
2104 Expr
:= New_Occurrence_Of
(Var_Id
, Loc
);
2106 -- A type conversion is needed when the validation variable and
2107 -- the validated object carry different types. This case occurs
2108 -- when the actual is qualified in some fashion.
2111 -- subtype Int is Integer range ...;
2112 -- procedure Call (Val : in out Integer);
2116 -- Call (Integer (Object));
2120 -- Var : Integer := Object; -- conversion to base type
2121 -- if not Var'Valid then -- validity check
2122 -- Call (Var); -- modify Var
2123 -- Object := Int (Var); -- conversion to subtype
2125 if Etype
(Var_Id
) /= Obj_Typ
then
2127 Make_Type_Conversion
(Loc
,
2128 Subtype_Mark
=> New_Occurrence_Of
(Obj_Typ
, Loc
),
2129 Expression
=> Expr
);
2135 -- Object := Object_Type (Var);
2137 Append_To
(Post_Call
,
2138 Make_Assignment_Statement
(Loc
,
2140 Expression
=> Expr
));
2142 -- If the flow reaches this point, then this routine was invoked with
2143 -- an actual which does not denote a validation variable.
2146 pragma Assert
(False);
2149 end Add_Validation_Call_By_Copy_Code
;
2151 ---------------------------
2152 -- Check_Fortran_Logical --
2153 ---------------------------
2155 procedure Check_Fortran_Logical
is
2156 Logical
: constant Entity_Id
:= Etype
(Formal
);
2159 -- Note: this is very incomplete, e.g. it does not handle arrays
2160 -- of logical values. This is really not the right approach at all???)
2163 if Convention
(Subp
) = Convention_Fortran
2164 and then Root_Type
(Etype
(Formal
)) = Standard_Boolean
2165 and then Ekind
(Formal
) /= E_In_Parameter
2167 Var
:= Make_Var
(Actual
);
2168 Append_To
(Post_Call
,
2169 Make_Assignment_Statement
(Loc
,
2170 Name
=> New_Occurrence_Of
(Var
, Loc
),
2172 Unchecked_Convert_To
(
2175 Left_Opnd
=> New_Occurrence_Of
(Var
, Loc
),
2177 Unchecked_Convert_To
(
2179 New_Occurrence_Of
(Standard_False
, Loc
))))));
2181 end Check_Fortran_Logical
;
2187 function Is_Legal_Copy
return Boolean is
2189 -- An attempt to copy a value of such a type can only occur if
2190 -- representation clauses give the actual a misaligned address.
2192 if Is_By_Reference_Type
(Etype
(Formal
))
2193 or else Is_Aliased
(Formal
)
2194 or else (Mechanism
(Formal
) = By_Reference
2195 and then not Has_Foreign_Convention
(Subp
))
2198 -- The actual may in fact be properly aligned but there is not
2199 -- enough front-end information to determine this. In that case
2200 -- gigi will emit an error or a warning if a copy is not legal,
2201 -- or generate the proper code.
2205 -- For users of Starlet, we assume that the specification of by-
2206 -- reference mechanism is mandatory. This may lead to unaligned
2207 -- objects but at least for DEC legacy code it is known to work.
2208 -- The warning will alert users of this code that a problem may
2211 elsif Mechanism
(Formal
) = By_Reference
2212 and then Ekind
(Scope
(Formal
)) = E_Procedure
2213 and then Is_Valued_Procedure
(Scope
(Formal
))
2216 ("by_reference actual may be misaligned??", Actual
);
2228 function Make_Var
(Actual
: Node_Id
) return Entity_Id
is
2232 if Is_Entity_Name
(Actual
) then
2233 return Entity
(Actual
);
2236 Var
:= Make_Temporary
(Loc
, 'T', Actual
);
2239 Make_Object_Renaming_Declaration
(Loc
,
2240 Defining_Identifier
=> Var
,
2242 New_Occurrence_Of
(Etype
(Actual
), Loc
),
2243 Name
=> Relocate_Node
(Actual
));
2245 Insert_Action
(N
, N_Node
);
2250 -------------------------
2251 -- Reset_Packed_Prefix --
2252 -------------------------
2254 procedure Reset_Packed_Prefix
is
2255 Pfx
: Node_Id
:= Actual
;
2258 Set_Analyzed
(Pfx
, False);
2260 Nkind
(Pfx
) not in N_Selected_Component | N_Indexed_Component
;
2261 Pfx
:= Prefix
(Pfx
);
2263 end Reset_Packed_Prefix
;
2265 ----------------------------------------
2266 -- Requires_Atomic_Or_Volatile_Copy --
2267 ----------------------------------------
2269 function Requires_Atomic_Or_Volatile_Copy
return Boolean is
2271 -- If the formal is already passed by copy, no need to do anything
2273 if Is_By_Copy_Type
(E_Formal
) then
2277 -- There is no requirement inside initialization procedures and this
2278 -- would generate copies for atomic or volatile composite components.
2280 if Inside_Init_Proc
then
2284 -- Check for atomicity mismatch
2286 if Is_Atomic_Object
(Actual
) and then not Is_Atomic
(E_Formal
)
2288 if Comes_From_Source
(N
) then
2290 ("??atomic actual passed by copy (RM C.6(19))", Actual
);
2295 -- Check for volatility mismatch
2297 if Is_Volatile_Object_Ref
(Actual
) and then not Is_Volatile
(E_Formal
)
2299 if Comes_From_Source
(N
) then
2301 ("??volatile actual passed by copy (RM C.6(19))", Actual
);
2307 end Requires_Atomic_Or_Volatile_Copy
;
2309 -- Start of processing for Expand_Actuals
2312 Post_Call
:= New_List
;
2314 Formal
:= First_Formal
(Subp
);
2315 Actual
:= First_Actual
(N
);
2316 while Present
(Formal
) loop
2317 E_Formal
:= Etype
(Formal
);
2318 E_Actual
:= Etype
(Actual
);
2320 -- Handle formals whose type comes from the limited view
2322 if From_Limited_With
(E_Formal
)
2323 and then Has_Non_Limited_View
(E_Formal
)
2325 E_Formal
:= Non_Limited_View
(E_Formal
);
2328 if Is_Scalar_Type
(E_Formal
)
2329 or else Nkind
(Actual
) = N_Slice
2331 Check_Fortran_Logical
;
2335 elsif Ekind
(Formal
) /= E_Out_Parameter
then
2337 -- The unusual case of the current instance of a protected type
2338 -- requires special handling. This can only occur in the context
2339 -- of a call within the body of a protected operation.
2341 if Is_Entity_Name
(Actual
)
2342 and then Ekind
(Entity
(Actual
)) = E_Protected_Type
2343 and then In_Open_Scopes
(Entity
(Actual
))
2345 if Scope
(Subp
) /= Entity
(Actual
) then
2347 ("operation outside protected type may not "
2348 & "call back its protected operations??", Actual
);
2352 Expand_Protected_Object_Reference
(N
, Entity
(Actual
)));
2355 -- Ada 2005 (AI-318-02): If the actual parameter is a call to a
2356 -- build-in-place function, then a temporary return object needs
2357 -- to be created and access to it must be passed to the function
2358 -- (and ensure that we have an activation chain defined for tasks
2359 -- and a Master variable).
2361 -- Currently we limit such functions to those with inherently
2362 -- limited result subtypes, but eventually we plan to expand the
2363 -- functions that are treated as build-in-place to include other
2364 -- composite result types.
2366 -- But do not do it here for intrinsic subprograms since this will
2367 -- be done properly after the subprogram is expanded.
2369 if Is_Intrinsic_Subprogram
(Subp
) then
2372 elsif Is_Build_In_Place_Function_Call
(Actual
) then
2373 if Might_Have_Tasks
(Etype
(Actual
)) then
2374 Build_Activation_Chain_Entity
(N
);
2375 Build_Master_Entity
(Etype
(Actual
));
2378 Make_Build_In_Place_Call_In_Anonymous_Context
(Actual
);
2380 -- Ada 2005 (AI-318-02): Specialization of the previous case for
2381 -- actuals containing build-in-place function calls whose returned
2382 -- object covers interface types.
2384 elsif Present
(Unqual_BIP_Iface_Function_Call
(Actual
)) then
2385 Build_Activation_Chain_Entity
(N
);
2386 Build_Master_Entity
(Etype
(Actual
));
2387 Make_Build_In_Place_Iface_Call_In_Anonymous_Context
(Actual
);
2390 Apply_Constraint_Check
(Actual
, E_Formal
);
2392 -- Out parameter case. No constraint checks on access type
2393 -- RM 6.4.1 (13), but on return a null-excluding check may be
2394 -- required (see below).
2396 elsif Is_Access_Type
(E_Formal
) then
2401 elsif Has_Discriminants
(Base_Type
(E_Formal
))
2402 or else Has_Non_Null_Base_Init_Proc
(E_Formal
)
2404 Apply_Constraint_Check
(Actual
, E_Formal
);
2409 Apply_Constraint_Check
(Actual
, Base_Type
(E_Formal
));
2412 -- Processing for IN-OUT and OUT parameters
2414 if Ekind
(Formal
) /= E_In_Parameter
then
2416 -- For type conversions of arrays, apply length/range checks
2418 if Is_Array_Type
(E_Formal
)
2419 and then Nkind
(Actual
) = N_Type_Conversion
2421 if Is_Constrained
(E_Formal
) then
2422 Apply_Length_Check
(Expression
(Actual
), E_Formal
);
2424 Apply_Range_Check
(Expression
(Actual
), E_Formal
);
2428 -- If argument is a type conversion for a type that is passed by
2429 -- copy, then we must pass the parameter by copy.
2431 if Nkind
(Actual
) = N_Type_Conversion
2433 (Is_Elementary_Type
(E_Formal
)
2434 or else Is_Bit_Packed_Array
(Etype
(Formal
))
2435 or else Is_Bit_Packed_Array
(Etype
(Expression
(Actual
)))
2437 -- Also pass by copy if change of representation
2439 or else not Has_Compatible_Representation
2440 (Target_Typ
=> Etype
(Formal
),
2441 Operand_Typ
=> Etype
(Expression
(Actual
))))
2443 Add_Call_By_Copy_Code
;
2445 -- References to components of bit-packed arrays are expanded
2446 -- at this point, rather than at the point of analysis of the
2447 -- actuals, to handle the expansion of the assignment to
2448 -- [in] out parameters.
2450 elsif Is_Ref_To_Bit_Packed_Array
(Actual
) then
2451 Add_Simple_Call_By_Copy_Code
(Force
=> True);
2453 -- If a nonscalar actual is possibly bit-aligned, we need a copy
2454 -- because the back-end cannot cope with such objects. In other
2455 -- cases where alignment forces a copy, the back-end generates
2456 -- it properly. It should not be generated unconditionally in the
2457 -- front-end because it does not know precisely the alignment
2458 -- requirements of the target, and makes too conservative an
2459 -- estimate, leading to superfluous copies or spurious errors
2460 -- on by-reference parameters.
2462 elsif Nkind
(Actual
) = N_Selected_Component
2464 Component_May_Be_Bit_Aligned
(Entity
(Selector_Name
(Actual
)))
2465 and then not Represented_As_Scalar
(Etype
(Formal
))
2467 Add_Simple_Call_By_Copy_Code
(Force
=> False);
2469 -- References to slices of bit-packed arrays are expanded
2471 elsif Is_Ref_To_Bit_Packed_Slice
(Actual
) then
2472 Add_Call_By_Copy_Code
;
2474 -- References to possibly unaligned slices of arrays are expanded
2476 elsif Is_Possibly_Unaligned_Slice
(Actual
) then
2477 Add_Call_By_Copy_Code
;
2479 -- Deal with access types where the actual subtype and the
2480 -- formal subtype are not the same, requiring a check.
2482 -- It is necessary to exclude tagged types because of "downward
2483 -- conversion" errors, but null-excluding checks on return may be
2486 elsif Is_Access_Type
(E_Formal
)
2487 and then not Is_Tagged_Type
(Designated_Type
(E_Formal
))
2488 and then (not Same_Type
(E_Formal
, E_Actual
)
2489 or else (Can_Never_Be_Null
(E_Actual
)
2490 and then not Can_Never_Be_Null
(E_Formal
)))
2492 Add_Call_By_Copy_Code
;
2494 -- We may need to force a copy because of atomicity or volatility
2497 elsif Requires_Atomic_Or_Volatile_Copy
then
2498 Add_Call_By_Copy_Code
;
2500 -- Add call-by-copy code for the case of scalar out parameters
2501 -- when it is not known at compile time that the subtype of the
2502 -- formal is a subrange of the subtype of the actual (or vice
2503 -- versa for in out parameters), in order to get range checks
2504 -- on such actuals. (Maybe this case should be handled earlier
2505 -- in the if statement???)
2507 elsif Is_Scalar_Type
(E_Formal
)
2509 (not In_Subrange_Of
(E_Formal
, E_Actual
)
2511 (Ekind
(Formal
) = E_In_Out_Parameter
2512 and then not In_Subrange_Of
(E_Actual
, E_Formal
)))
2514 Add_Call_By_Copy_Code
;
2516 -- The actual denotes a variable which captures the value of an
2517 -- object for validation purposes. Add a copy-back to reflect any
2518 -- potential changes in value back into the original object.
2520 -- Var : ... := Object;
2521 -- if not Var'Valid then -- validity check
2522 -- Call (Var); -- modify var
2523 -- Object := Var; -- update Object
2525 elsif Is_Validation_Variable_Reference
(Actual
) then
2526 Add_Validation_Call_By_Copy_Code
(Actual
);
2529 -- RM 3.2.4 (23/3): A predicate is checked on in-out and out
2530 -- by-reference parameters on exit from the call. If the actual
2531 -- is a derived type and the operation is inherited, the body
2532 -- of the operation will not contain a call to the predicate
2533 -- function, so it must be done explicitly after the call. Ditto
2534 -- if the actual is an entity of a predicated subtype.
2536 -- The rule refers to by-reference types, but a check is needed
2537 -- for by-copy types as well. That check is subsumed by the rule
2538 -- for subtype conversion on assignment, but we can generate the
2539 -- required check now.
2541 -- Note also that Subp may be either a subprogram entity for
2542 -- direct calls, or a type entity for indirect calls, which must
2543 -- be handled separately because the name does not denote an
2544 -- overloadable entity.
2546 By_Ref_Predicate_Check
: declare
2547 Aund
: constant Entity_Id
:= Underlying_Type
(E_Actual
);
2557 if Predicate_Enabled
(Atyp
)
2559 -- Skip predicate checks for special cases
2561 and then Predicate_Tests_On_Arguments
(Subp
)
2563 Append_To
(Post_Call
,
2564 Make_Predicate_Check
(Atyp
, Actual
));
2566 end By_Ref_Predicate_Check
;
2568 -- Processing for IN parameters
2571 -- Generate range check if required
2573 if Do_Range_Check
(Actual
) then
2574 Generate_Range_Check
(Actual
, E_Formal
, CE_Range_Check_Failed
);
2577 -- For IN parameters in the bit-packed array case, we expand an
2578 -- indexed component (the circuit in Exp_Ch4 deliberately left
2579 -- indexed components appearing as actuals untouched, so that
2580 -- the special processing above for the OUT and IN OUT cases
2581 -- could be performed. We could make the test in Exp_Ch4 more
2582 -- complex and have it detect the parameter mode, but it is
2583 -- easier simply to handle all cases here.)
2585 if Nkind
(Actual
) = N_Indexed_Component
2586 and then Is_Bit_Packed_Array
(Etype
(Prefix
(Actual
)))
2588 Reset_Packed_Prefix
;
2589 Expand_Packed_Element_Reference
(Actual
);
2591 -- If we have a reference to a bit-packed array, we copy it, since
2592 -- the actual must be byte aligned.
2594 -- Is this really necessary in all cases???
2596 elsif Is_Ref_To_Bit_Packed_Array
(Actual
) then
2597 Add_Simple_Call_By_Copy_Code
(Force
=> True);
2599 -- If we have a C++ constructor call, we need to create the object
2601 elsif Is_CPP_Constructor_Call
(Actual
) then
2602 Add_Simple_Call_By_Copy_Code
(Force
=> True);
2604 -- If a nonscalar actual is possibly unaligned, we need a copy
2606 elsif Is_Possibly_Unaligned_Object
(Actual
)
2607 and then not Represented_As_Scalar
(Etype
(Formal
))
2609 Add_Simple_Call_By_Copy_Code
(Force
=> False);
2611 -- Similarly, we have to expand slices of packed arrays here
2612 -- because the result must be byte aligned.
2614 elsif Is_Ref_To_Bit_Packed_Slice
(Actual
) then
2615 Add_Call_By_Copy_Code
;
2617 -- Only processing remaining is to pass by copy if this is a
2618 -- reference to a possibly unaligned slice, since the caller
2619 -- expects an appropriately aligned argument.
2621 elsif Is_Possibly_Unaligned_Slice
(Actual
) then
2622 Add_Call_By_Copy_Code
;
2624 -- We may need to force a copy because of atomicity or volatility
2627 elsif Requires_Atomic_Or_Volatile_Copy
then
2628 Add_Call_By_Copy_Code
;
2630 -- An unusual case: a current instance of an enclosing task can be
2631 -- an actual, and must be replaced by a reference to self.
2633 elsif Is_Entity_Name
(Actual
)
2634 and then Is_Task_Type
(Entity
(Actual
))
2636 if In_Open_Scopes
(Entity
(Actual
)) then
2638 (Make_Function_Call
(Loc
,
2639 Name
=> New_Occurrence_Of
(RTE
(RE_Self
), Loc
))));
2642 -- A task type cannot otherwise appear as an actual
2645 raise Program_Error
;
2650 -- Type-invariant checks for in-out and out parameters, as well as
2651 -- for in parameters of procedures (AI05-0289 and AI12-0044).
2653 if Ekind
(Formal
) /= E_In_Parameter
2654 or else Ekind
(Subp
) = E_Procedure
2656 Caller_Side_Invariant_Checks
: declare
2658 function Is_Public_Subp
return Boolean;
2659 -- Check whether the subprogram being called is a visible
2660 -- operation of the type of the actual. Used to determine
2661 -- whether an invariant check must be generated on the
2664 ---------------------
2665 -- Is_Public_Subp --
2666 ---------------------
2668 function Is_Public_Subp
return Boolean is
2669 Pack
: constant Entity_Id
:= Scope
(Subp
);
2670 Subp_Decl
: Node_Id
;
2673 if not Is_Subprogram
(Subp
) then
2676 -- The operation may be inherited, or a primitive of the
2680 Nkind
(Parent
(Subp
)) in N_Private_Extension_Declaration
2681 | N_Full_Type_Declaration
2683 Subp_Decl
:= Parent
(Subp
);
2686 Subp_Decl
:= Unit_Declaration_Node
(Subp
);
2689 return Ekind
(Pack
) = E_Package
2691 List_Containing
(Subp_Decl
) =
2692 Visible_Declarations
2693 (Specification
(Unit_Declaration_Node
(Pack
)));
2696 -- Start of processing for Caller_Side_Invariant_Checks
2699 -- We generate caller-side invariant checks in two cases:
2701 -- a) when calling an inherited operation, where there is an
2702 -- implicit view conversion of the actual to the parent type.
2704 -- b) When the conversion is explicit
2706 -- We treat these cases separately because the required
2707 -- conversion for a) is added later when expanding the call.
2709 if Has_Invariants
(Etype
(Actual
))
2711 Nkind
(Parent
(Etype
(Actual
)))
2712 = N_Private_Extension_Declaration
2714 if Comes_From_Source
(N
) and then Is_Public_Subp
then
2715 Append_To
(Post_Call
, Make_Invariant_Call
(Actual
));
2718 elsif Nkind
(Actual
) = N_Type_Conversion
2719 and then Has_Invariants
(Etype
(Expression
(Actual
)))
2721 if Comes_From_Source
(N
) and then Is_Public_Subp
then
2723 (Post_Call
, Make_Invariant_Call
(Expression
(Actual
)));
2726 end Caller_Side_Invariant_Checks
;
2729 Next_Formal
(Formal
);
2730 Next_Actual
(Actual
);
2738 procedure Expand_Call
(N
: Node_Id
) is
2739 Post_Call
: List_Id
;
2741 -- If this is an indirect call through an Access_To_Subprogram
2742 -- with contract specifications, it is rewritten as a call to
2743 -- the corresponding Access_Subprogram_Wrapper with the same
2744 -- actuals, whose body contains a naked indirect call (which
2745 -- itself must not be rewritten, to prevent infinite recursion).
2747 Must_Rewrite_Indirect_Call
: constant Boolean :=
2748 Ada_Version
>= Ada_2022
2749 and then Nkind
(Name
(N
)) = N_Explicit_Dereference
2750 and then Ekind
(Etype
(Name
(N
))) = E_Subprogram_Type
2752 (Access_Subprogram_Wrapper
(Etype
(Name
(N
))));
2755 pragma Assert
(Nkind
(N
) in N_Entry_Call_Statement
2757 | N_Procedure_Call_Statement
);
2759 -- Check that this is not the call in the body of the access
2760 -- subprogram wrapper or the postconditions wrapper.
2762 if Must_Rewrite_Indirect_Call
2763 and then (not Is_Overloadable
(Current_Scope
)
2764 or else not (Is_Access_Subprogram_Wrapper
(Current_Scope
)
2766 (Chars
(Current_Scope
) = Name_uWrapped_Statements
2767 and then Is_Access_Subprogram_Wrapper
2768 (Scope
(Current_Scope
)))))
2771 Loc
: constant Source_Ptr
:= Sloc
(N
);
2772 Wrapper
: constant Entity_Id
:=
2773 Access_Subprogram_Wrapper
(Etype
(Name
(N
)));
2774 Ptr
: constant Node_Id
:= Prefix
(Name
(N
));
2775 Ptr_Type
: constant Entity_Id
:= Etype
(Ptr
);
2776 Typ
: constant Entity_Id
:= Etype
(N
);
2779 Parms
: List_Id
:= Parameter_Associations
(N
);
2783 -- The last actual in the call is the pointer itself.
2784 -- If the aspect is inherited, convert the pointer to the
2785 -- parent type that specifies the contract.
2786 -- If the original access_to_subprogram has defaults for
2787 -- in_parameters, the call may include named associations, so
2788 -- we create one for the pointer as well.
2790 if Is_Derived_Type
(Ptr_Type
)
2791 and then Ptr_Type
/= Etype
(Last_Formal
(Wrapper
))
2794 Make_Type_Conversion
(Loc
,
2796 (Etype
(Last_Formal
(Wrapper
)), Loc
), Ptr
);
2802 -- Handle parameterless subprogram.
2809 (Make_Parameter_Association
(Loc
,
2810 Selector_Name
=> Make_Identifier
(Loc
,
2811 Chars
(Last_Formal
(Wrapper
))),
2812 Explicit_Actual_Parameter
=> Ptr_Act
),
2815 if Nkind
(N
) = N_Procedure_Call_Statement
then
2816 New_N
:= Make_Procedure_Call_Statement
(Loc
,
2817 Name
=> New_Occurrence_Of
(Wrapper
, Loc
),
2818 Parameter_Associations
=> Parms
);
2820 New_N
:= Make_Function_Call
(Loc
,
2821 Name
=> New_Occurrence_Of
(Wrapper
, Loc
),
2822 Parameter_Associations
=> Parms
);
2826 Analyze_And_Resolve
(N
, Typ
);
2830 Expand_Call_Helper
(N
, Post_Call
);
2831 Insert_Post_Call_Actions
(N
, Post_Call
);
2835 ------------------------
2836 -- Expand_Call_Helper --
2837 ------------------------
2839 -- This procedure handles expansion of function calls and procedure call
2840 -- statements (i.e. it serves as the body for Expand_N_Function_Call and
2841 -- Expand_N_Procedure_Call_Statement). Processing for calls includes:
2843 -- Replace call to Raise_Exception by Raise_Exception_Always if possible
2844 -- Provide values of actuals for all formals in Extra_Formals list
2845 -- Replace "call" to enumeration literal function by literal itself
2846 -- Rewrite call to predefined operator as operator
2847 -- Replace actuals to in-out parameters that are numeric conversions,
2848 -- with explicit assignment to temporaries before and after the call.
2850 -- Note that the list of actuals has been filled with default expressions
2851 -- during semantic analysis of the call. Only the extra actuals required
2852 -- for the 'Constrained attribute and for accessibility checks are added
2855 procedure Expand_Call_Helper
(N
: Node_Id
; Post_Call
: out List_Id
) is
2856 Loc
: constant Source_Ptr
:= Sloc
(N
);
2857 Call_Node
: Node_Id
:= N
;
2858 Extra_Actuals
: List_Id
:= No_List
;
2859 Prev
: Node_Id
:= Empty
;
2861 procedure Add_Actual_Parameter
(Insert_Param
: Node_Id
);
2862 -- Adds one entry to the end of the actual parameter list. Used for
2863 -- default parameters and for extra actuals (for Extra_Formals). The
2864 -- argument is an N_Parameter_Association node.
2866 procedure Add_Cond_Expression_Extra_Actual
(Formal
: Entity_Id
);
2867 -- Adds extra accessibility actuals in the case of a conditional
2868 -- expression corresponding to Formal.
2870 -- Note: Conditional expressions used as actuals for anonymous access
2871 -- formals complicate the process of propagating extra accessibility
2872 -- actuals and must be handled in a recursive fashion since they can
2873 -- be embedded within each other.
2875 procedure Add_Extra_Actual
(Expr
: Node_Id
; EF
: Entity_Id
);
2876 -- Adds an extra actual to the list of extra actuals. Expr is the
2877 -- expression for the value of the actual, EF is the entity for the
2880 procedure Add_View_Conversion_Invariants
2881 (Formal
: Entity_Id
;
2883 -- Adds invariant checks for every intermediate type between the range
2884 -- of a view converted argument to its ancestor (from parent to child).
2886 function Can_Fold_Predicate_Call
(P
: Entity_Id
) return Boolean;
2887 -- Try to constant-fold a predicate check, which often enough is a
2888 -- simple arithmetic expression that can be computed statically if
2889 -- its argument is static. This cleans up the output of CCG, even
2890 -- though useless predicate checks will be generally removed by
2891 -- back-end optimizations.
2893 procedure Check_Subprogram_Variant
;
2894 -- Emit a call to the internally generated procedure with checks for
2895 -- aspect Subprogram_Variant, if present and enabled.
2897 function Inherited_From_Formal
(S
: Entity_Id
) return Entity_Id
;
2898 -- Within an instance, a type derived from an untagged formal derived
2899 -- type inherits from the original parent, not from the actual. The
2900 -- current derivation mechanism has the derived type inherit from the
2901 -- actual, which is only correct outside of the instance. If the
2902 -- subprogram is inherited, we test for this particular case through a
2903 -- convoluted tree traversal before setting the proper subprogram to be
2906 function In_Unfrozen_Instance
(E
: Entity_Id
) return Boolean;
2907 -- Return true if E comes from an instance that is not yet frozen
2909 function Is_Class_Wide_Interface_Type
(E
: Entity_Id
) return Boolean;
2910 -- Return True when E is a class-wide interface type or an access to
2911 -- a class-wide interface type.
2913 function Is_Direct_Deep_Call
(Subp
: Entity_Id
) return Boolean;
2914 -- Determine if Subp denotes a non-dispatching call to a Deep routine
2916 function New_Value
(From
: Node_Id
) return Node_Id
;
2917 -- From is the original Expression. New_Value is equivalent to a call
2918 -- to Duplicate_Subexpr with an explicit dereference when From is an
2919 -- access parameter.
2921 --------------------------
2922 -- Add_Actual_Parameter --
2923 --------------------------
2925 procedure Add_Actual_Parameter
(Insert_Param
: Node_Id
) is
2926 Actual_Expr
: constant Node_Id
:=
2927 Explicit_Actual_Parameter
(Insert_Param
);
2930 -- Case of insertion is first named actual
2932 if No
(Prev
) or else
2933 Nkind
(Parent
(Prev
)) /= N_Parameter_Association
2935 Set_Next_Named_Actual
2936 (Insert_Param
, First_Named_Actual
(Call_Node
));
2937 Set_First_Named_Actual
(Call_Node
, Actual_Expr
);
2940 if No
(Parameter_Associations
(Call_Node
)) then
2941 Set_Parameter_Associations
(Call_Node
, New_List
);
2944 Append
(Insert_Param
, Parameter_Associations
(Call_Node
));
2947 Insert_After
(Prev
, Insert_Param
);
2950 -- Case of insertion is not first named actual
2953 Set_Next_Named_Actual
2954 (Insert_Param
, Next_Named_Actual
(Parent
(Prev
)));
2955 Set_Next_Named_Actual
(Parent
(Prev
), Actual_Expr
);
2956 Append
(Insert_Param
, Parameter_Associations
(Call_Node
));
2959 Prev
:= Actual_Expr
;
2960 end Add_Actual_Parameter
;
2962 --------------------------------------
2963 -- Add_Cond_Expression_Extra_Actual --
2964 --------------------------------------
2966 procedure Add_Cond_Expression_Extra_Actual
2967 (Formal
: Entity_Id
)
2972 procedure Insert_Level_Assign
(Branch
: Node_Id
);
2973 -- Recursively add assignment of the level temporary on each branch
2974 -- while moving through nested conditional expressions.
2976 -------------------------
2977 -- Insert_Level_Assign --
2978 -------------------------
2980 procedure Insert_Level_Assign
(Branch
: Node_Id
) is
2982 procedure Expand_Branch
(Res_Assn
: Node_Id
);
2983 -- Perform expansion or iterate further within nested
2984 -- conditionals given the object declaration or assignment to
2985 -- result object created during expansion which represents a
2986 -- branch of the conditional expression.
2992 procedure Expand_Branch
(Res_Assn
: Node_Id
) is
2994 pragma Assert
(Nkind
(Res_Assn
) in
2995 N_Assignment_Statement |
2996 N_Object_Declaration
);
2998 -- There are more nested conditional expressions so we must go
3001 if Nkind
(Expression
(Res_Assn
)) = N_Expression_With_Actions
3003 Nkind
(Original_Node
(Expression
(Res_Assn
)))
3004 in N_Case_Expression | N_If_Expression
3007 (Expression
(Res_Assn
));
3009 -- Add the level assignment
3012 Insert_Before_And_Analyze
(Res_Assn
,
3013 Make_Assignment_Statement
(Loc
,
3014 Name
=> New_Occurrence_Of
(Lvl
, Loc
),
3017 (Expr
=> Expression
(Res_Assn
),
3018 Level
=> Dynamic_Level
,
3019 Allow_Alt_Model
=> False)));
3026 -- Start of processing for Insert_Level_Assign
3029 -- Examine further nested condtionals
3031 pragma Assert
(Nkind
(Branch
) =
3032 N_Expression_With_Actions
);
3034 -- Find the relevant statement in the actions
3036 Cond
:= First
(Actions
(Branch
));
3037 while Present
(Cond
) loop
3038 exit when Nkind
(Cond
) in N_Case_Statement | N_If_Statement
;
3042 -- The conditional expression may have been optimized away, so
3043 -- examine the actions in the branch.
3046 Expand_Branch
(Last
(Actions
(Branch
)));
3048 -- Iterate through if expression branches
3050 elsif Nkind
(Cond
) = N_If_Statement
then
3051 Expand_Branch
(Last
(Then_Statements
(Cond
)));
3052 Expand_Branch
(Last
(Else_Statements
(Cond
)));
3054 -- Iterate through case alternatives
3056 elsif Nkind
(Cond
) = N_Case_Statement
then
3058 Alt
:= First
(Alternatives
(Cond
));
3059 while Present
(Alt
) loop
3060 Expand_Branch
(Last
(Statements
(Alt
)));
3064 end Insert_Level_Assign
;
3066 -- Start of processing for cond expression case
3069 -- Create declaration of a temporary to store the accessibility
3070 -- level of each branch of the conditional expression.
3072 Lvl
:= Make_Temporary
(Loc
, 'L');
3073 Decl
:= Make_Object_Declaration
(Loc
,
3074 Defining_Identifier
=> Lvl
,
3075 Object_Definition
=>
3076 New_Occurrence_Of
(Standard_Natural
, Loc
));
3078 -- Install the declaration and perform necessary expansion if we
3079 -- are dealing with a procedure call.
3081 if Nkind
(Call_Node
) = N_Procedure_Call_Statement
then
3086 -- If_Exp_Res : Typ;
3088 -- Lvl := 0; -- Access level
3089 -- If_Exp_Res := Exp;
3091 -- in If_Exp_Res end;},
3096 Insert_Before_And_Analyze
(Call_Node
, Decl
);
3098 -- Ditto for a function call. Note that we do not wrap the function
3099 -- call into an expression with action to avoid bad interactions with
3100 -- Exp_Ch4.Process_Transient_In_Expression.
3104 -- Lvl : Natural; -- placed above the function call
3110 -- Lvl := 0; -- Access level
3111 -- If_Exp_Res := Exp;
3112 -- in If_Exp_Res end;},
3117 Insert_Action
(Call_Node
, Decl
);
3118 Analyze
(Call_Node
);
3121 -- Decorate the conditional expression with assignments to our level
3124 Insert_Level_Assign
(Prev
);
3126 -- Make our level temporary the passed actual
3129 (Expr
=> New_Occurrence_Of
(Lvl
, Loc
),
3130 EF
=> Extra_Accessibility
(Formal
));
3131 end Add_Cond_Expression_Extra_Actual
;
3133 ----------------------
3134 -- Add_Extra_Actual --
3135 ----------------------
3137 procedure Add_Extra_Actual
(Expr
: Node_Id
; EF
: Entity_Id
) is
3138 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
3141 if Extra_Actuals
= No_List
then
3142 Extra_Actuals
:= New_List
;
3143 Set_Parent
(Extra_Actuals
, Call_Node
);
3146 Append_To
(Extra_Actuals
,
3147 Make_Parameter_Association
(Loc
,
3148 Selector_Name
=> New_Occurrence_Of
(EF
, Loc
),
3149 Explicit_Actual_Parameter
=> Expr
));
3151 Analyze_And_Resolve
(Expr
, Etype
(EF
));
3153 if Nkind
(Call_Node
) = N_Function_Call
then
3154 Set_Is_Accessibility_Actual
(Parent
(Expr
));
3156 end Add_Extra_Actual
;
3158 ------------------------------------
3159 -- Add_View_Conversion_Invariants --
3160 ------------------------------------
3162 procedure Add_View_Conversion_Invariants
3163 (Formal
: Entity_Id
;
3167 Curr_Typ
: Entity_Id
;
3168 Inv_Checks
: List_Id
;
3169 Par_Typ
: Entity_Id
;
3172 Inv_Checks
:= No_List
;
3174 -- Extract the argument from a potentially nested set of view
3178 while Nkind
(Arg
) = N_Type_Conversion
loop
3179 Arg
:= Expression
(Arg
);
3182 -- Move up the derivation chain starting with the type of the formal
3183 -- parameter down to the type of the actual object.
3186 Par_Typ
:= Etype
(Arg
);
3187 while Par_Typ
/= Etype
(Formal
) and Par_Typ
/= Curr_Typ
loop
3188 Curr_Typ
:= Par_Typ
;
3190 if Has_Invariants
(Curr_Typ
)
3191 and then Present
(Invariant_Procedure
(Curr_Typ
))
3193 -- Verify the invariant of the current type. Generate:
3195 -- <Curr_Typ>Invariant (Curr_Typ (Arg));
3197 Prepend_New_To
(Inv_Checks
,
3198 Make_Procedure_Call_Statement
(Loc
,
3201 (Invariant_Procedure
(Curr_Typ
), Loc
),
3202 Parameter_Associations
=> New_List
(
3203 Make_Type_Conversion
(Loc
,
3204 Subtype_Mark
=> New_Occurrence_Of
(Curr_Typ
, Loc
),
3205 Expression
=> New_Copy_Tree
(Arg
)))));
3208 Par_Typ
:= Base_Type
(Etype
(Curr_Typ
));
3211 -- If the node is a function call the generated tests have been
3212 -- already handled in Insert_Post_Call_Actions.
3214 if not Is_Empty_List
(Inv_Checks
)
3215 and then Nkind
(Call_Node
) = N_Procedure_Call_Statement
3217 Insert_Actions_After
(Call_Node
, Inv_Checks
);
3219 end Add_View_Conversion_Invariants
;
3221 -----------------------------
3222 -- Can_Fold_Predicate_Call --
3223 -----------------------------
3225 function Can_Fold_Predicate_Call
(P
: Entity_Id
) return Boolean is
3228 function Augments_Other_Dynamic_Predicate
(DP_Aspect_Spec
: Node_Id
)
3230 -- Given a Dynamic_Predicate aspect aspecification for a
3231 -- discrete type, returns True iff another DP specification
3232 -- applies (indirectly, via a subtype type or a derived type)
3233 -- to the same entity that this aspect spec applies to.
3235 function May_Fold
(N
: Node_Id
) return Traverse_Result
;
3236 -- The predicate expression is foldable if it only contains operators
3237 -- and literals. During this check, we also replace occurrences of
3238 -- the formal of the constructed predicate function with the static
3239 -- value of the actual. This is done on a copy of the analyzed
3240 -- expression for the predicate.
3242 --------------------------------------
3243 -- Augments_Other_Dynamic_Predicate --
3244 --------------------------------------
3246 function Augments_Other_Dynamic_Predicate
(DP_Aspect_Spec
: Node_Id
)
3249 Aspect_Bearer
: Entity_Id
:= Entity
(DP_Aspect_Spec
);
3252 Aspect_Bearer
:= Nearest_Ancestor
(Aspect_Bearer
);
3254 if No
(Aspect_Bearer
) then
3259 Aspect_Spec
: constant Node_Id
:=
3260 Find_Aspect
(Aspect_Bearer
, Aspect_Dynamic_Predicate
);
3262 if Present
(Aspect_Spec
)
3263 and then Aspect_Spec
/= DP_Aspect_Spec
3265 -- Found another Dynamic_Predicate aspect spec
3270 end Augments_Other_Dynamic_Predicate
;
3276 function May_Fold
(N
: Node_Id
) return Traverse_Result
is
3282 when N_Expanded_Name
3285 if Ekind
(Entity
(N
)) = E_In_Parameter
3286 and then Entity
(N
) = First_Entity
(P
)
3288 Rewrite
(N
, New_Copy
(Actual
));
3289 Set_Is_Static_Expression
(N
);
3292 elsif Ekind
(Entity
(N
)) = E_Enumeration_Literal
then
3299 when N_Case_Expression
3304 when N_Integer_Literal
=>
3312 function Try_Fold
is new Traverse_Func
(May_Fold
);
3314 -- Other Local variables
3316 Subt
: constant Entity_Id
:= Etype
(First_Entity
(P
));
3320 -- Start of processing for Can_Fold_Predicate_Call
3323 -- Folding is only interesting if the actual is static and its type
3324 -- has a Dynamic_Predicate aspect. For CodePeer we preserve the
3327 Actual
:= First
(Parameter_Associations
(Call_Node
));
3328 Aspect
:= Find_Aspect
(Subt
, Aspect_Dynamic_Predicate
);
3330 -- If actual is a declared constant, retrieve its value
3332 if Is_Entity_Name
(Actual
)
3333 and then Ekind
(Entity
(Actual
)) = E_Constant
3335 Actual
:= Constant_Value
(Entity
(Actual
));
3339 or else Nkind
(Actual
) /= N_Integer_Literal
3340 or else not Has_Dynamic_Predicate_Aspect
(Subt
)
3343 -- Do not fold if multiple applicable predicate aspects
3344 or else Has_Aspect
(Subt
, Aspect_Static_Predicate
)
3345 or else Has_Aspect
(Subt
, Aspect_Predicate
)
3346 or else Augments_Other_Dynamic_Predicate
(Aspect
)
3347 or else CodePeer_Mode
3352 -- Retrieve the analyzed expression for the predicate
3354 Pred
:= New_Copy_Tree
(Expression
(Aspect
));
3356 if Try_Fold
(Pred
) = OK
then
3357 Rewrite
(Call_Node
, Pred
);
3358 Analyze_And_Resolve
(Call_Node
, Standard_Boolean
);
3361 -- Otherwise continue the expansion of the function call
3366 end Can_Fold_Predicate_Call
;
3368 ------------------------------
3369 -- Check_Subprogram_Variant --
3370 ------------------------------
3372 procedure Check_Subprogram_Variant
is
3374 function Duplicate_Params_Without_Extra_Actuals
3375 (Call_Node
: Node_Id
) return List_Id
;
3376 -- Duplicate actual parameters of Call_Node into New_Call without
3379 --------------------------------------------
3380 -- Duplicate_Params_Without_Extra_Actuals --
3381 --------------------------------------------
3383 function Duplicate_Params_Without_Extra_Actuals
3384 (Call_Node
: Node_Id
) return List_Id
3386 Proc_Id
: constant Entity_Id
:= Entity
(Name
(Call_Node
));
3387 Actuals
: constant List_Id
:= Parameter_Associations
(Call_Node
);
3389 Actual
: Node_Or_Entity_Id
;
3393 if Actuals
= No_List
then
3398 Actual
:= First
(Actuals
);
3399 Formal
:= First_Formal
(Proc_Id
);
3401 while Present
(Formal
)
3402 and then Formal
/= Extra_Formals
(Proc_Id
)
3404 Append
(New_Copy
(Actual
), NL
);
3407 Next_Formal
(Formal
);
3412 end Duplicate_Params_Without_Extra_Actuals
;
3416 Variant_Prag
: constant Node_Id
:=
3417 Get_Pragma
(Current_Scope
, Pragma_Subprogram_Variant
);
3420 Pragma_Arg1
: Node_Id
;
3421 Variant_Proc
: Entity_Id
;
3424 if Present
(Variant_Prag
) and then Is_Checked
(Variant_Prag
) then
3427 Expression
(First
(Pragma_Argument_Associations
(Variant_Prag
)));
3429 -- If pragma parameter is still an aggregate, it comes from a
3430 -- structural variant, which is not expanded and ignored for
3431 -- run-time execution.
3433 if Nkind
(Pragma_Arg1
) = N_Aggregate
then
3438 (First
(Component_Associations
(Pragma_Arg1
))))) =
3443 -- Otherwise, analysis of the pragma rewrites its argument with a
3444 -- reference to the internally generated procedure.
3446 Variant_Proc
:= Entity
(Pragma_Arg1
);
3449 Make_Procedure_Call_Statement
(Loc
,
3451 New_Occurrence_Of
(Variant_Proc
, Loc
),
3452 Parameter_Associations
=>
3453 Duplicate_Params_Without_Extra_Actuals
(Call_Node
));
3455 Insert_Action
(Call_Node
, New_Call
);
3457 pragma Assert
(Etype
(New_Call
) /= Any_Type
3458 or else Serious_Errors_Detected
> 0);
3460 end Check_Subprogram_Variant
;
3462 ---------------------------
3463 -- Inherited_From_Formal --
3464 ---------------------------
3466 function Inherited_From_Formal
(S
: Entity_Id
) return Entity_Id
is
3468 Gen_Par
: Entity_Id
;
3469 Gen_Prim
: Elist_Id
;
3474 -- If the operation is inherited, it is attached to the corresponding
3475 -- type derivation. If the parent in the derivation is a generic
3476 -- actual, it is a subtype of the actual, and we have to recover the
3477 -- original derived type declaration to find the proper parent.
3479 if Nkind
(Parent
(S
)) /= N_Full_Type_Declaration
3480 or else not Is_Derived_Type
(Defining_Identifier
(Parent
(S
)))
3481 or else Nkind
(Type_Definition
(Original_Node
(Parent
(S
)))) /=
3482 N_Derived_Type_Definition
3483 or else not In_Instance
3490 (Type_Definition
(Original_Node
(Parent
(S
))));
3492 if Nkind
(Indic
) = N_Subtype_Indication
then
3493 Par
:= Entity
(Subtype_Mark
(Indic
));
3495 Par
:= Entity
(Indic
);
3499 if not Is_Generic_Actual_Type
(Par
)
3500 or else Is_Tagged_Type
(Par
)
3501 or else Nkind
(Parent
(Par
)) /= N_Subtype_Declaration
3502 or else not In_Open_Scopes
(Scope
(Par
))
3506 Gen_Par
:= Generic_Parent_Type
(Parent
(Par
));
3509 -- If the actual has no generic parent type, the formal is not
3510 -- a formal derived type, so nothing to inherit.
3512 if No
(Gen_Par
) then
3516 -- If the generic parent type is still the generic type, this is a
3517 -- private formal, not a derived formal, and there are no operations
3518 -- inherited from the formal.
3520 if Nkind
(Parent
(Gen_Par
)) = N_Formal_Type_Declaration
then
3524 Gen_Prim
:= Collect_Primitive_Operations
(Gen_Par
);
3526 Elmt
:= First_Elmt
(Gen_Prim
);
3527 while Present
(Elmt
) loop
3528 if Chars
(Node
(Elmt
)) = Chars
(S
) then
3534 F1
:= First_Formal
(S
);
3535 F2
:= First_Formal
(Node
(Elmt
));
3537 and then Present
(F2
)
3539 if Etype
(F1
) = Etype
(F2
)
3540 or else Etype
(F2
) = Gen_Par
3546 exit; -- not the right subprogram
3558 raise Program_Error
;
3559 end Inherited_From_Formal
;
3561 --------------------------
3562 -- In_Unfrozen_Instance --
3563 --------------------------
3565 function In_Unfrozen_Instance
(E
: Entity_Id
) return Boolean is
3570 while Present
(S
) and then S
/= Standard_Standard
loop
3571 if Is_Generic_Instance
(S
)
3572 and then Present
(Freeze_Node
(S
))
3573 and then not Analyzed
(Freeze_Node
(S
))
3582 end In_Unfrozen_Instance
;
3584 ----------------------------------
3585 -- Is_Class_Wide_Interface_Type --
3586 ----------------------------------
3588 function Is_Class_Wide_Interface_Type
(E
: Entity_Id
) return Boolean is
3590 Typ
: Entity_Id
:= E
;
3593 if Has_Non_Limited_View
(Typ
) then
3594 Typ
:= Non_Limited_View
(Typ
);
3597 if Ekind
(Typ
) = E_Anonymous_Access_Type
then
3598 DDT
:= Directly_Designated_Type
(Typ
);
3600 if Has_Non_Limited_View
(DDT
) then
3601 DDT
:= Non_Limited_View
(DDT
);
3604 return Is_Class_Wide_Type
(DDT
) and then Is_Interface
(DDT
);
3606 return Is_Class_Wide_Type
(Typ
) and then Is_Interface
(Typ
);
3608 end Is_Class_Wide_Interface_Type
;
3610 -------------------------
3611 -- Is_Direct_Deep_Call --
3612 -------------------------
3614 function Is_Direct_Deep_Call
(Subp
: Entity_Id
) return Boolean is
3616 if Is_TSS
(Subp
, TSS_Deep_Adjust
)
3617 or else Is_TSS
(Subp
, TSS_Deep_Finalize
)
3618 or else Is_TSS
(Subp
, TSS_Deep_Initialize
)
3625 Actual
:= First
(Parameter_Associations
(Call_Node
));
3626 Formal
:= First_Formal
(Subp
);
3627 while Present
(Actual
)
3628 and then Present
(Formal
)
3630 if Nkind
(Actual
) = N_Identifier
3631 and then Is_Controlling_Actual
(Actual
)
3632 and then Etype
(Actual
) = Etype
(Formal
)
3638 Next_Formal
(Formal
);
3644 end Is_Direct_Deep_Call
;
3650 function New_Value
(From
: Node_Id
) return Node_Id
is
3651 Res
: constant Node_Id
:= Duplicate_Subexpr
(From
);
3653 if Is_Access_Type
(Etype
(From
)) then
3654 return Make_Explicit_Dereference
(Sloc
(From
), Prefix
=> Res
);
3662 Remote
: constant Boolean := Is_Remote_Call
(Call_Node
);
3665 Orig_Subp
: Entity_Id
:= Empty
;
3666 Param_Count
: Positive;
3667 Parent_Formal
: Entity_Id
;
3668 Parent_Subp
: Entity_Id
;
3672 CW_Interface_Formals_Present
: Boolean := False;
3674 -- Start of processing for Expand_Call_Helper
3677 Post_Call
:= New_List
;
3679 -- Expand the function or procedure call if the first actual has a
3680 -- declared dimension aspect, and the subprogram is declared in one
3681 -- of the dimension I/O packages.
3683 if Ada_Version
>= Ada_2012
3684 and then Nkind
(Call_Node
) in N_Subprogram_Call
3685 and then Present
(Parameter_Associations
(Call_Node
))
3687 Expand_Put_Call_With_Symbol
(Call_Node
);
3690 -- Ignore if previous error
3692 if Nkind
(Call_Node
) in N_Has_Etype
3693 and then Etype
(Call_Node
) = Any_Type
3698 -- Call using access to subprogram with explicit dereference
3700 if Nkind
(Name
(Call_Node
)) = N_Explicit_Dereference
then
3701 Subp
:= Etype
(Name
(Call_Node
));
3702 Parent_Subp
:= Empty
;
3704 -- Case of call to simple entry, where the Name is a selected component
3705 -- whose prefix is the task, and whose selector name is the entry name
3707 elsif Nkind
(Name
(Call_Node
)) = N_Selected_Component
then
3708 Subp
:= Entity
(Selector_Name
(Name
(Call_Node
)));
3709 Parent_Subp
:= Empty
;
3711 -- Case of call to member of entry family, where Name is an indexed
3712 -- component, with the prefix being a selected component giving the
3713 -- task and entry family name, and the index being the entry index.
3715 elsif Nkind
(Name
(Call_Node
)) = N_Indexed_Component
then
3716 Subp
:= Entity
(Selector_Name
(Prefix
(Name
(Call_Node
))));
3717 Parent_Subp
:= Empty
;
3722 Subp
:= Entity
(Name
(Call_Node
));
3723 Parent_Subp
:= Alias
(Subp
);
3725 -- Replace call to Raise_Exception by call to Raise_Exception_Always
3726 -- if we can tell that the first parameter cannot possibly be null.
3727 -- This improves efficiency by avoiding a run-time test.
3729 -- We do not do this if Raise_Exception_Always does not exist, which
3730 -- can happen in configurable run time profiles which provide only a
3733 if Is_RTE
(Subp
, RE_Raise_Exception
)
3734 and then RTE_Available
(RE_Raise_Exception_Always
)
3737 FA
: constant Node_Id
:=
3738 Original_Node
(First_Actual
(Call_Node
));
3741 -- The case we catch is where the first argument is obtained
3742 -- using the Identity attribute (which must always be
3745 if Nkind
(FA
) = N_Attribute_Reference
3746 and then Attribute_Name
(FA
) = Name_Identity
3748 Subp
:= RTE
(RE_Raise_Exception_Always
);
3749 Set_Name
(Call_Node
, New_Occurrence_Of
(Subp
, Loc
));
3754 if Ekind
(Subp
) = E_Entry
then
3755 Parent_Subp
:= Empty
;
3759 -- Ensure that the called subprogram has all its formals
3761 if not Is_Frozen
(Subp
) then
3762 Create_Extra_Formals
(Subp
);
3765 -- Ada 2005 (AI-345): We have a procedure call as a triggering
3766 -- alternative in an asynchronous select or as an entry call in
3767 -- a conditional or timed select. Check whether the procedure call
3768 -- is a renaming of an entry and rewrite it as an entry call.
3770 if Ada_Version
>= Ada_2005
3771 and then Nkind
(Call_Node
) = N_Procedure_Call_Statement
3773 ((Nkind
(Parent
(Call_Node
)) = N_Triggering_Alternative
3774 and then Triggering_Statement
(Parent
(Call_Node
)) = Call_Node
)
3776 (Nkind
(Parent
(Call_Node
)) = N_Entry_Call_Alternative
3777 and then Entry_Call_Statement
(Parent
(Call_Node
)) = Call_Node
))
3781 Ren_Root
: Entity_Id
:= Subp
;
3784 -- This may be a chain of renamings, find the root
3786 if Present
(Alias
(Ren_Root
)) then
3787 Ren_Root
:= Alias
(Ren_Root
);
3790 if Present
(Parent
(Ren_Root
))
3791 and then Present
(Original_Node
(Parent
(Parent
(Ren_Root
))))
3793 Ren_Decl
:= Original_Node
(Parent
(Parent
(Ren_Root
)));
3795 if Nkind
(Ren_Decl
) = N_Subprogram_Renaming_Declaration
then
3797 Make_Entry_Call_Statement
(Loc
,
3799 New_Copy_Tree
(Name
(Ren_Decl
)),
3800 Parameter_Associations
=>
3802 (Parameter_Associations
(Call_Node
))));
3810 -- If this is a call to a predicate function, try to constant fold it
3812 if Nkind
(Call_Node
) = N_Function_Call
3813 and then Is_Entity_Name
(Name
(Call_Node
))
3814 and then Is_Predicate_Function
(Subp
)
3815 and then Can_Fold_Predicate_Call
(Subp
)
3820 if Transform_Function_Array
3821 and then Nkind
(Call_Node
) = N_Function_Call
3822 and then Is_Entity_Name
(Name
(Call_Node
))
3825 Func_Id
: constant Entity_Id
:=
3826 Ultimate_Alias
(Entity
(Name
(Call_Node
)));
3828 -- When generating C code, transform a function call that returns
3829 -- a constrained array type into procedure form.
3831 if Rewritten_For_C
(Func_Id
) then
3833 -- For internally generated calls ensure that they reference
3834 -- the entity of the spec of the called function (needed since
3835 -- the expander may generate calls using the entity of their
3838 if not Comes_From_Source
(Call_Node
)
3839 and then Nkind
(Unit_Declaration_Node
(Func_Id
)) =
3842 Set_Entity
(Name
(Call_Node
),
3843 Corresponding_Function
3844 (Corresponding_Procedure
(Func_Id
)));
3847 Rewrite_Function_Call_For_C
(Call_Node
);
3850 -- Also introduce a temporary for functions that return a record
3851 -- called within another procedure or function call, since records
3852 -- are passed by pointer in the generated C code, and we cannot
3853 -- take a pointer from a subprogram call.
3855 elsif Modify_Tree_For_C
3856 and then Nkind
(Parent
(Call_Node
)) in N_Subprogram_Call
3857 and then Is_Record_Type
(Etype
(Func_Id
))
3860 Temp_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
3865 -- Temp : ... := Func_Call (...);
3868 Make_Object_Declaration
(Loc
,
3869 Defining_Identifier
=> Temp_Id
,
3870 Object_Definition
=>
3871 New_Occurrence_Of
(Etype
(Func_Id
), Loc
),
3873 Make_Function_Call
(Loc
,
3875 New_Occurrence_Of
(Func_Id
, Loc
),
3876 Parameter_Associations
=>
3877 Parameter_Associations
(Call_Node
)));
3879 Insert_Action
(Parent
(Call_Node
), Decl
);
3880 Rewrite
(Call_Node
, New_Occurrence_Of
(Temp_Id
, Loc
));
3887 -- First step, compute extra actuals, corresponding to any Extra_Formals
3888 -- present. Note that we do not access Extra_Formals directly, instead
3889 -- we simply note the presence of the extra formals as we process the
3890 -- regular formals collecting corresponding actuals in Extra_Actuals.
3892 -- We also generate any required range checks for actuals for in formals
3893 -- as we go through the loop, since this is a convenient place to do it.
3894 -- (Though it seems that this would be better done in Expand_Actuals???)
3896 -- Special case: Thunks must not compute the extra actuals; they must
3897 -- just propagate to the target primitive their extra actuals.
3899 if Is_Thunk
(Current_Scope
)
3900 and then Thunk_Entity
(Current_Scope
) = Subp
3901 and then Present
(Extra_Formals
(Subp
))
3903 pragma Assert
(Extra_Formals_Match_OK
(Current_Scope
, Subp
));
3906 Target_Formal
: Entity_Id
;
3907 Thunk_Formal
: Entity_Id
;
3910 Target_Formal
:= Extra_Formals
(Subp
);
3911 Thunk_Formal
:= Extra_Formals
(Current_Scope
);
3912 while Present
(Target_Formal
) loop
3914 (Expr
=> New_Occurrence_Of
(Thunk_Formal
, Loc
),
3915 EF
=> Thunk_Formal
);
3917 Target_Formal
:= Extra_Formal
(Target_Formal
);
3918 Thunk_Formal
:= Extra_Formal
(Thunk_Formal
);
3921 while Is_Non_Empty_List
(Extra_Actuals
) loop
3922 Add_Actual_Parameter
(Remove_Head
(Extra_Actuals
));
3925 -- Mark the call as processed build-in-place call; required
3926 -- to avoid adding the extra formals twice.
3928 if Nkind
(Call_Node
) = N_Function_Call
then
3929 Set_Is_Expanded_Build_In_Place_Call
(Call_Node
);
3932 Expand_Actuals
(Call_Node
, Subp
, Post_Call
);
3933 pragma Assert
(Is_Empty_List
(Post_Call
));
3934 pragma Assert
(Check_Number_Of_Actuals
(Call_Node
, Subp
));
3935 pragma Assert
(Check_BIP_Actuals
(Call_Node
, Subp
));
3940 Formal
:= First_Formal
(Subp
);
3941 Actual
:= First_Actual
(Call_Node
);
3943 while Present
(Formal
) loop
3944 -- Prepare to examine current entry
3948 -- Ada 2005 (AI-251): Check if any formal is a class-wide interface
3949 -- to expand it in a further round.
3951 CW_Interface_Formals_Present
:=
3952 CW_Interface_Formals_Present
3953 or else Is_Class_Wide_Interface_Type
(Etype
(Formal
));
3955 -- Create possible extra actual for constrained case. Usually, the
3956 -- extra actual is of the form actual'constrained, but since this
3957 -- attribute is only available for unconstrained records, TRUE is
3958 -- expanded if the type of the formal happens to be constrained (for
3959 -- instance when this procedure is inherited from an unconstrained
3960 -- record to a constrained one) or if the actual has no discriminant
3961 -- (its type is constrained). An exception to this is the case of a
3962 -- private type without discriminants. In this case we pass FALSE
3963 -- because the object has underlying discriminants with defaults.
3965 if Present
(Extra_Constrained
(Formal
)) then
3966 if Is_Private_Type
(Etype
(Prev
))
3967 and then not Has_Discriminants
(Base_Type
(Etype
(Prev
)))
3970 (Expr
=> New_Occurrence_Of
(Standard_False
, Loc
),
3971 EF
=> Extra_Constrained
(Formal
));
3973 elsif Is_Constrained
(Etype
(Formal
))
3974 or else not Has_Discriminants
(Etype
(Prev
))
3977 (Expr
=> New_Occurrence_Of
(Standard_True
, Loc
),
3978 EF
=> Extra_Constrained
(Formal
));
3980 -- Do not produce extra actuals for Unchecked_Union parameters.
3981 -- Jump directly to the end of the loop.
3983 elsif Is_Unchecked_Union
(Base_Type
(Etype
(Actual
))) then
3984 goto Skip_Extra_Actual_Generation
;
3987 -- If the actual is a type conversion, then the constrained
3988 -- test applies to the actual, not the target type.
3994 -- Test for unchecked conversions as well, which can occur
3995 -- as out parameter actuals on calls to stream procedures.
3998 while Nkind
(Act_Prev
) in N_Type_Conversion
3999 | N_Unchecked_Type_Conversion
4001 Act_Prev
:= Expression
(Act_Prev
);
4004 -- If the expression is a conversion of a dereference, this
4005 -- is internally generated code that manipulates addresses,
4006 -- e.g. when building interface tables. No check should
4007 -- occur in this case, and the discriminated object is not
4008 -- directly at hand.
4010 if not Comes_From_Source
(Actual
)
4011 and then Nkind
(Actual
) = N_Unchecked_Type_Conversion
4012 and then Nkind
(Act_Prev
) = N_Explicit_Dereference
4015 (Expr
=> New_Occurrence_Of
(Standard_False
, Loc
),
4016 EF
=> Extra_Constrained
(Formal
));
4021 Make_Attribute_Reference
(Sloc
(Prev
),
4023 Duplicate_Subexpr_No_Checks
4024 (Act_Prev
, Name_Req
=> True),
4025 Attribute_Name
=> Name_Constrained
),
4026 EF
=> Extra_Constrained
(Formal
));
4032 -- Create possible extra actual for accessibility level
4034 if Present
(Extra_Accessibility
(Formal
)) then
4035 -- Ada 2005 (AI-251): Thunks must propagate the extra actuals of
4036 -- accessibility levels.
4038 if Is_Thunk
(Current_Scope
) then
4040 Parm_Ent
: Entity_Id
;
4043 if Is_Controlling_Actual
(Actual
) then
4045 -- Find the corresponding actual of the thunk
4047 Parm_Ent
:= First_Entity
(Current_Scope
);
4048 for J
in 2 .. Param_Count
loop
4049 Next_Entity
(Parm_Ent
);
4052 -- Handle unchecked conversion of access types generated
4053 -- in thunks (cf. Expand_Interface_Thunk).
4055 elsif Is_Access_Type
(Etype
(Actual
))
4056 and then Nkind
(Actual
) = N_Unchecked_Type_Conversion
4058 Parm_Ent
:= Entity
(Expression
(Actual
));
4060 else pragma Assert
(Is_Entity_Name
(Actual
));
4061 Parm_Ent
:= Entity
(Actual
);
4065 (Expr
=> Accessibility_Level
4067 Level
=> Dynamic_Level
,
4068 Allow_Alt_Model
=> False),
4069 EF
=> Extra_Accessibility
(Formal
));
4072 -- Conditional expressions
4074 elsif Nkind
(Prev
) = N_Expression_With_Actions
4075 and then Nkind
(Original_Node
(Prev
)) in
4076 N_If_Expression | N_Case_Expression
4078 Add_Cond_Expression_Extra_Actual
(Formal
);
4080 -- Internal constant generated to remove side effects (normally
4081 -- from the expansion of dispatching calls).
4083 -- First verify the actual is internal
4085 elsif not Comes_From_Source
(Prev
)
4086 and then not Is_Rewrite_Substitution
(Prev
)
4088 -- Next check that the actual is a constant
4090 and then Nkind
(Prev
) = N_Identifier
4091 and then Ekind
(Entity
(Prev
)) = E_Constant
4092 and then Nkind
(Parent
(Entity
(Prev
))) = N_Object_Declaration
4094 -- Generate the accessibility level based on the expression in
4095 -- the constant's declaration.
4098 (Expr
=> Accessibility_Level
4100 (Parent
(Entity
(Prev
))),
4101 Level
=> Dynamic_Level
,
4102 Allow_Alt_Model
=> False),
4103 EF
=> Extra_Accessibility
(Formal
));
4109 (Expr
=> Accessibility_Level
4111 Level
=> Dynamic_Level
,
4112 Allow_Alt_Model
=> False),
4113 EF
=> Extra_Accessibility
(Formal
));
4117 -- Perform the check of 4.6(49) that prevents a null value from being
4118 -- passed as an actual to an access parameter. Note that the check
4119 -- is elided in the common cases of passing an access attribute or
4120 -- access parameter as an actual. Also, we currently don't enforce
4121 -- this check for expander-generated actuals and when -gnatdj is set.
4123 if Ada_Version
>= Ada_2005
then
4125 -- Ada 2005 (AI-231): Check null-excluding access types. Note that
4126 -- the intent of 6.4.1(13) is that null-exclusion checks should
4127 -- not be done for 'out' parameters, even though it refers only
4128 -- to constraint checks, and a null_exclusion is not a constraint.
4129 -- Note that AI05-0196-1 corrects this mistake in the RM.
4131 if Is_Access_Type
(Etype
(Formal
))
4132 and then Can_Never_Be_Null
(Etype
(Formal
))
4133 and then Ekind
(Formal
) /= E_Out_Parameter
4134 and then Nkind
(Prev
) /= N_Raise_Constraint_Error
4135 and then (Known_Null
(Prev
)
4136 or else not Can_Never_Be_Null
(Etype
(Prev
)))
4138 Install_Null_Excluding_Check
(Prev
);
4141 -- Ada_Version < Ada_2005
4144 if Ekind
(Etype
(Formal
)) /= E_Anonymous_Access_Type
4145 or else Access_Checks_Suppressed
(Subp
)
4149 elsif Debug_Flag_J
then
4152 elsif not Comes_From_Source
(Prev
) then
4155 elsif Is_Entity_Name
(Prev
)
4156 and then Ekind
(Etype
(Prev
)) = E_Anonymous_Access_Type
4160 elsif Nkind
(Prev
) in N_Allocator | N_Attribute_Reference
then
4164 Install_Null_Excluding_Check
(Prev
);
4168 -- Perform appropriate validity checks on parameters that
4171 if Validity_Checks_On
then
4172 if (Ekind
(Formal
) = E_In_Parameter
4173 and then Validity_Check_In_Params
)
4175 (Ekind
(Formal
) = E_In_Out_Parameter
4176 and then Validity_Check_In_Out_Params
)
4178 -- If the actual is an indexed component of a packed type (or
4179 -- is an indexed or selected component whose prefix recursively
4180 -- meets this condition), it has not been expanded yet. It will
4181 -- be copied in the validity code that follows, and has to be
4182 -- expanded appropriately, so reanalyze it.
4184 -- What we do is just to unset analyzed bits on prefixes till
4185 -- we reach something that does not have a prefix.
4192 while Nkind
(Nod
) in
4193 N_Indexed_Component | N_Selected_Component
4195 Set_Analyzed
(Nod
, False);
4196 Nod
:= Prefix
(Nod
);
4200 Ensure_Valid
(Actual
);
4204 -- For IN OUT and OUT parameters, ensure that subscripts are valid
4205 -- since this is a left side reference. We only do this for calls
4206 -- from the source program since we assume that compiler generated
4207 -- calls explicitly generate any required checks. We also need it
4208 -- only if we are doing standard validity checks, since clearly it is
4209 -- not needed if validity checks are off, and in subscript validity
4210 -- checking mode, all indexed components are checked with a call
4211 -- directly from Expand_N_Indexed_Component.
4213 if Comes_From_Source
(Call_Node
)
4214 and then Ekind
(Formal
) /= E_In_Parameter
4215 and then Validity_Checks_On
4216 and then Validity_Check_Default
4217 and then not Validity_Check_Subscripts
4219 Check_Valid_Lvalue_Subscripts
(Actual
);
4222 -- Mark any scalar OUT parameter that is a simple variable as no
4223 -- longer known to be valid (unless the type is always valid). This
4224 -- reflects the fact that if an OUT parameter is never set in a
4225 -- procedure, then it can become invalid on the procedure return.
4227 if Ekind
(Formal
) = E_Out_Parameter
4228 and then Is_Entity_Name
(Actual
)
4229 and then Ekind
(Entity
(Actual
)) = E_Variable
4230 and then not Is_Known_Valid
(Etype
(Actual
))
4232 Set_Is_Known_Valid
(Entity
(Actual
), False);
4235 -- For an OUT or IN OUT parameter, if the actual is an entity, then
4236 -- clear current values, since they can be clobbered. We are probably
4237 -- doing this in more places than we need to, but better safe than
4238 -- sorry when it comes to retaining bad current values.
4240 if Ekind
(Formal
) /= E_In_Parameter
4241 and then Is_Entity_Name
(Actual
)
4242 and then Present
(Entity
(Actual
))
4245 Ent
: constant Entity_Id
:= Entity
(Actual
);
4249 -- For an OUT or IN OUT parameter that is an assignable entity,
4250 -- we do not want to clobber the Last_Assignment field, since
4251 -- if it is set, it was precisely because it is indeed an OUT
4252 -- or IN OUT parameter. We do reset the Is_Known_Valid flag
4253 -- since the subprogram could have returned in invalid value.
4255 if Is_Assignable
(Ent
) then
4256 Sav
:= Last_Assignment
(Ent
);
4257 Kill_Current_Values
(Ent
);
4258 Set_Last_Assignment
(Ent
, Sav
);
4259 Set_Is_Known_Valid
(Ent
, False);
4260 Set_Is_True_Constant
(Ent
, False);
4262 -- For all other cases, just kill the current values
4265 Kill_Current_Values
(Ent
);
4270 -- If the formal is class-wide and the actual is an aggregate, force
4271 -- evaluation so that the back end who does not know about class-wide
4272 -- type, does not generate a temporary of the wrong size.
4274 if not Is_Class_Wide_Type
(Etype
(Formal
)) then
4277 elsif Nkind
(Actual
) = N_Aggregate
4278 or else (Nkind
(Actual
) = N_Qualified_Expression
4279 and then Nkind
(Expression
(Actual
)) = N_Aggregate
)
4281 Force_Evaluation
(Actual
);
4284 -- In a remote call, if the formal is of a class-wide type, check
4285 -- that the actual meets the requirements described in E.4(18).
4287 if Remote
and then Is_Class_Wide_Type
(Etype
(Formal
)) then
4288 Insert_Action
(Actual
,
4289 Make_Transportable_Check
(Loc
,
4290 Duplicate_Subexpr_Move_Checks
(Actual
)));
4293 -- Perform invariant checks for all intermediate types in a view
4294 -- conversion after successful return from a call that passes the
4295 -- view conversion as an IN OUT or OUT parameter (RM 7.3.2 (12/3,
4296 -- 13/3, 14/3)). Consider only source conversion in order to avoid
4297 -- generating spurious checks on complex expansion such as object
4298 -- initialization through an extension aggregate.
4300 if Comes_From_Source
(Call_Node
)
4301 and then Ekind
(Formal
) /= E_In_Parameter
4302 and then Nkind
(Actual
) = N_Type_Conversion
4304 Add_View_Conversion_Invariants
(Formal
, Actual
);
4307 -- Generating C the initialization of an allocator is performed by
4308 -- means of individual statements, and hence it must be done before
4311 if Modify_Tree_For_C
4312 and then Nkind
(Actual
) = N_Allocator
4313 and then Nkind
(Expression
(Actual
)) = N_Qualified_Expression
4315 Remove_Side_Effects
(Actual
);
4318 -- This label is required when skipping extra actual generation for
4319 -- Unchecked_Union parameters.
4321 <<Skip_Extra_Actual_Generation
>>
4323 Param_Count
:= Param_Count
+ 1;
4324 Next_Actual
(Actual
);
4325 Next_Formal
(Formal
);
4328 -- If we are calling an Ada 2012 function which needs to have the
4329 -- "accessibility level determined by the point of call" (AI05-0234)
4330 -- passed in to it, then pass it in.
4332 if Ekind
(Subp
) in E_Function | E_Operator | E_Subprogram_Type
4334 Present
(Extra_Accessibility_Of_Result
(Ultimate_Alias
(Subp
)))
4337 Extra_Form
: Node_Id
:= Empty
;
4338 Level
: Node_Id
:= Empty
;
4341 -- Detect cases where the function call has been internally
4342 -- generated by examining the original node and return library
4343 -- level - taking care to avoid ignoring function calls expanded
4344 -- in prefix notation.
4346 if Nkind
(Original_Node
(Call_Node
)) not in N_Function_Call
4347 | N_Selected_Component
4348 | N_Indexed_Component
4350 Level
:= Make_Integer_Literal
4351 (Loc
, Scope_Depth
(Standard_Standard
));
4353 -- Otherwise get the level normally based on the call node
4356 Level
:= Accessibility_Level
4358 Level
=> Dynamic_Level
,
4359 Allow_Alt_Model
=> False);
4362 -- It may be possible that we are re-expanding an already
4363 -- expanded call when are are dealing with dispatching ???
4365 if not Present
(Parameter_Associations
(Call_Node
))
4366 or else Nkind
(Last
(Parameter_Associations
(Call_Node
)))
4367 /= N_Parameter_Association
4368 or else not Is_Accessibility_Actual
4369 (Last
(Parameter_Associations
(Call_Node
)))
4371 Extra_Form
:= Extra_Accessibility_Of_Result
4372 (Ultimate_Alias
(Subp
));
4381 -- If we are expanding the RHS of an assignment we need to check if tag
4382 -- propagation is needed. You might expect this processing to be in
4383 -- Analyze_Assignment but has to be done earlier (bottom-up) because the
4384 -- assignment might be transformed to a declaration for an unconstrained
4385 -- value if the expression is classwide.
4387 if Nkind
(Call_Node
) = N_Function_Call
4388 and then Is_Tag_Indeterminate
(Call_Node
)
4389 and then Is_Entity_Name
(Name
(Call_Node
))
4392 Ass
: Node_Id
:= Empty
;
4395 if Nkind
(Parent
(Call_Node
)) = N_Assignment_Statement
then
4396 Ass
:= Parent
(Call_Node
);
4398 elsif Nkind
(Parent
(Call_Node
)) = N_Qualified_Expression
4399 and then Nkind
(Parent
(Parent
(Call_Node
))) =
4400 N_Assignment_Statement
4402 Ass
:= Parent
(Parent
(Call_Node
));
4404 elsif Nkind
(Parent
(Call_Node
)) = N_Explicit_Dereference
4405 and then Nkind
(Parent
(Parent
(Call_Node
))) =
4406 N_Assignment_Statement
4408 Ass
:= Parent
(Parent
(Call_Node
));
4412 and then Is_Class_Wide_Type
(Etype
(Name
(Ass
)))
4414 -- Move the error messages below to sem???
4416 if Is_Access_Type
(Etype
(Call_Node
)) then
4417 if Designated_Type
(Etype
(Call_Node
)) /=
4418 Root_Type
(Etype
(Name
(Ass
)))
4421 ("tag-indeterminate expression must have designated "
4422 & "type& (RM 5.2 (6))",
4423 Call_Node
, Root_Type
(Etype
(Name
(Ass
))));
4425 Propagate_Tag
(Name
(Ass
), Call_Node
);
4428 elsif Etype
(Call_Node
) /= Root_Type
(Etype
(Name
(Ass
))) then
4430 ("tag-indeterminate expression must have type & "
4432 Call_Node
, Root_Type
(Etype
(Name
(Ass
))));
4435 Propagate_Tag
(Name
(Ass
), Call_Node
);
4438 -- The call will be rewritten as a dispatching call, and
4439 -- expanded as such.
4446 -- Ada 2005 (AI-251): If some formal is a class-wide interface, expand
4447 -- it to point to the correct secondary virtual table.
4449 if Nkind
(Call_Node
) in N_Subprogram_Call
4450 and then CW_Interface_Formals_Present
4452 Expand_Interface_Actuals
(Call_Node
);
4455 -- Install class-wide preconditions runtime check when this is a
4456 -- dispatching primitive that has or inherits class-wide preconditions;
4457 -- otherwise no runtime check is installed.
4459 if Nkind
(Call_Node
) in N_Subprogram_Call
4460 and then Is_Dispatching_Operation
(Subp
)
4462 Install_Class_Preconditions_Check
(Call_Node
);
4465 -- Deals with Dispatch_Call if we still have a call, before expanding
4466 -- extra actuals since this will be done on the re-analysis of the
4467 -- dispatching call. Note that we do not try to shorten the actual list
4468 -- for a dispatching call, it would not make sense to do so. Expansion
4469 -- of dispatching calls is suppressed for VM targets, because the VM
4470 -- back-ends directly handle the generation of dispatching calls and
4471 -- would have to undo any expansion to an indirect call.
4473 if Nkind
(Call_Node
) in N_Subprogram_Call
4474 and then Present
(Controlling_Argument
(Call_Node
))
4476 if Tagged_Type_Expansion
then
4477 Expand_Dispatching_Call
(Call_Node
);
4479 -- Expand_Dispatching_Call takes care of all the needed processing
4487 Call_Typ
: constant Entity_Id
:= Etype
(Call_Node
);
4488 Typ
: constant Entity_Id
:= Find_Dispatching_Type
(Subp
);
4489 Eq_Prim_Op
: Entity_Id
:= Empty
;
4492 Prev_Call
: Node_Id
;
4495 Apply_Tag_Checks
(Call_Node
);
4497 if not Is_Limited_Type
(Typ
) then
4498 Eq_Prim_Op
:= Find_Prim_Op
(Typ
, Name_Op_Eq
);
4501 -- If this is a dispatching "=", we must first compare the
4502 -- tags so we generate: x.tag = y.tag and then x = y
4504 if Subp
= Eq_Prim_Op
then
4506 -- Mark the node as analyzed to avoid reanalyzing this
4507 -- dispatching call (which would cause a never-ending loop)
4509 Prev_Call
:= Relocate_Node
(Call_Node
);
4510 Set_Analyzed
(Prev_Call
);
4512 Param
:= First_Actual
(Call_Node
);
4518 Make_Selected_Component
(Loc
,
4519 Prefix
=> New_Value
(Param
),
4522 (First_Tag_Component
(Typ
), Loc
)),
4525 Make_Selected_Component
(Loc
,
4527 Unchecked_Convert_To
(Typ
,
4528 New_Value
(Next_Actual
(Param
))),
4531 (First_Tag_Component
(Typ
), Loc
))),
4532 Right_Opnd
=> Prev_Call
);
4534 Rewrite
(Call_Node
, New_Call
);
4536 (Call_Node
, Call_Typ
, Suppress
=> All_Checks
);
4539 -- Expansion of a dispatching call results in an indirect call,
4540 -- which in turn causes current values to be killed (see
4541 -- Resolve_Call), so on VM targets we do the call here to
4542 -- ensure consistent warnings between VM and non-VM targets.
4544 Kill_Current_Values
;
4546 -- If this is a dispatching "=" then we must update the reference
4547 -- to the call node because we generated:
4548 -- x.tag = y.tag and then x = y
4550 if Subp
= Eq_Prim_Op
then
4551 Call_Node
:= Right_Opnd
(Call_Node
);
4556 -- Similarly, expand calls to RCI subprograms on which pragma
4557 -- All_Calls_Remote applies. The rewriting will be reanalyzed
4558 -- later. Do this only when the call comes from source since we
4559 -- do not want such a rewriting to occur in expanded code.
4561 if Is_All_Remote_Call
(Call_Node
) then
4562 Expand_All_Calls_Remote_Subprogram_Call
(Call_Node
);
4564 -- Similarly, do not add extra actuals for an entry call whose entity
4565 -- is a protected procedure, or for an internal protected subprogram
4566 -- call, because it will be rewritten as a protected subprogram call
4567 -- and reanalyzed (see Expand_Protected_Subprogram_Call).
4569 elsif Is_Protected_Type
(Scope
(Subp
))
4570 and then Ekind
(Subp
) in E_Procedure | E_Function
4574 -- During that loop we gathered the extra actuals (the ones that
4575 -- correspond to Extra_Formals), so now they can be appended.
4578 while Is_Non_Empty_List
(Extra_Actuals
) loop
4579 Add_Actual_Parameter
(Remove_Head
(Extra_Actuals
));
4583 -- At this point we have all the actuals, so this is the point at which
4584 -- the various expansion activities for actuals is carried out.
4586 Expand_Actuals
(Call_Node
, Subp
, Post_Call
);
4588 -- If it is a recursive call then call the internal procedure that
4589 -- verifies Subprogram_Variant contract (if present and enabled).
4590 -- Detecting calls to subprogram aliases is necessary for recursive
4591 -- calls in instances of generic subprograms, where the renaming of
4592 -- the current subprogram is called.
4594 if Is_Subprogram
(Subp
)
4595 and then not Is_Ignored_Ghost_Entity
(Subp
)
4596 and then Same_Or_Aliased_Subprograms
(Subp
, Current_Scope
)
4598 Check_Subprogram_Variant
;
4601 -- Verify that the actuals do not share storage. This check must be done
4602 -- on the caller side rather that inside the subprogram to avoid issues
4603 -- of parameter passing.
4605 if Check_Aliasing_Of_Parameters
then
4606 Apply_Parameter_Aliasing_Checks
(Call_Node
, Subp
);
4609 -- If the subprogram is a renaming, or if it is inherited, replace it in
4610 -- the call with the name of the actual subprogram being called. If this
4611 -- is a dispatching call, the run-time decides what to call. The Alias
4612 -- attribute does not apply to entries.
4614 if Nkind
(Call_Node
) /= N_Entry_Call_Statement
4615 and then No
(Controlling_Argument
(Call_Node
))
4616 and then Present
(Parent_Subp
)
4617 and then not Is_Direct_Deep_Call
(Subp
)
4619 if Present
(Inherited_From_Formal
(Subp
)) then
4620 Parent_Subp
:= Inherited_From_Formal
(Subp
);
4622 Parent_Subp
:= Ultimate_Alias
(Parent_Subp
);
4625 -- The below setting of Entity is suspect, see F109-018 discussion???
4627 Set_Entity
(Name
(Call_Node
), Parent_Subp
);
4629 -- Inspect all formals of derived subprogram Subp. Compare parameter
4630 -- types with the parent subprogram and check whether an actual may
4631 -- need a type conversion to the corresponding formal of the parent
4634 -- Not clear whether intrinsic subprograms need such conversions. ???
4636 if not Is_Intrinsic_Subprogram
(Parent_Subp
)
4637 or else Is_Generic_Instance
(Parent_Subp
)
4640 procedure Convert
(Act
: Node_Id
; Typ
: Entity_Id
);
4641 -- Rewrite node Act as a type conversion of Act to Typ. Analyze
4642 -- and resolve the newly generated construct.
4648 procedure Convert
(Act
: Node_Id
; Typ
: Entity_Id
) is
4650 Rewrite
(Act
, OK_Convert_To
(Typ
, Act
));
4651 Analyze_And_Resolve
(Act
, Typ
);
4656 Actual_Typ
: Entity_Id
;
4657 Formal_Typ
: Entity_Id
;
4658 Parent_Typ
: Entity_Id
;
4661 Actual
:= First_Actual
(Call_Node
);
4662 Formal
:= First_Formal
(Subp
);
4663 Parent_Formal
:= First_Formal
(Parent_Subp
);
4664 while Present
(Formal
) loop
4665 Actual_Typ
:= Etype
(Actual
);
4666 Formal_Typ
:= Etype
(Formal
);
4667 Parent_Typ
:= Etype
(Parent_Formal
);
4669 -- For an IN parameter of a scalar type, the derived formal
4670 -- type and parent formal type differ, and the parent formal
4671 -- type and actual type do not match statically.
4673 if Is_Scalar_Type
(Formal_Typ
)
4674 and then Ekind
(Formal
) = E_In_Parameter
4675 and then Formal_Typ
/= Parent_Typ
4677 not Subtypes_Statically_Match
(Parent_Typ
, Actual_Typ
)
4678 and then not Raises_Constraint_Error
(Actual
)
4680 Convert
(Actual
, Parent_Typ
);
4682 -- For access types, the parent formal type and actual type
4685 elsif Is_Access_Type
(Formal_Typ
)
4686 and then Base_Type
(Parent_Typ
) /= Base_Type
(Actual_Typ
)
4688 if Ekind
(Formal
) /= E_In_Parameter
then
4689 Convert
(Actual
, Parent_Typ
);
4691 elsif Ekind
(Parent_Typ
) = E_Anonymous_Access_Type
4692 and then Designated_Type
(Parent_Typ
) /=
4693 Designated_Type
(Actual_Typ
)
4694 and then not Is_Controlling_Formal
(Formal
)
4696 -- This unchecked conversion is not necessary unless
4697 -- inlining is enabled, because in that case the type
4698 -- mismatch may become visible in the body about to be
4702 Unchecked_Convert_To
(Parent_Typ
, Actual
));
4703 Analyze_And_Resolve
(Actual
, Parent_Typ
);
4706 -- If there is a change of representation, then generate a
4707 -- warning, and do the change of representation.
4709 elsif not Has_Compatible_Representation
4710 (Target_Typ
=> Formal_Typ
,
4711 Operand_Typ
=> Parent_Typ
)
4714 ("??change of representation required", Actual
);
4715 Convert
(Actual
, Parent_Typ
);
4717 -- For array and record types, the parent formal type and
4718 -- derived formal type have different sizes or pragma Pack
4721 elsif ((Is_Array_Type
(Formal_Typ
)
4722 and then Is_Array_Type
(Parent_Typ
))
4724 (Is_Record_Type
(Formal_Typ
)
4725 and then Is_Record_Type
(Parent_Typ
)))
4726 and then Known_Esize
(Formal_Typ
)
4727 and then Known_Esize
(Parent_Typ
)
4729 (Esize
(Formal_Typ
) /= Esize
(Parent_Typ
)
4730 or else Has_Pragma_Pack
(Formal_Typ
) /=
4731 Has_Pragma_Pack
(Parent_Typ
))
4733 Convert
(Actual
, Parent_Typ
);
4736 Next_Actual
(Actual
);
4737 Next_Formal
(Formal
);
4738 Next_Formal
(Parent_Formal
);
4744 Subp
:= Parent_Subp
;
4747 -- Deal with case where call is an explicit dereference
4749 if Nkind
(Name
(Call_Node
)) = N_Explicit_Dereference
then
4751 -- Handle case of access to protected subprogram type
4753 if Is_Access_Protected_Subprogram_Type
4754 (Base_Type
(Etype
(Prefix
(Name
(Call_Node
)))))
4756 -- If this is a call through an access to protected operation, the
4757 -- prefix has the form (object'address, operation'access). Rewrite
4758 -- as a for other protected calls: the object is the 1st parameter
4759 -- of the list of actuals.
4766 Ptr
: constant Node_Id
:= Prefix
(Name
(Call_Node
));
4768 T
: constant Entity_Id
:=
4769 Equivalent_Type
(Base_Type
(Etype
(Ptr
)));
4771 D_T
: constant Entity_Id
:=
4772 Designated_Type
(Base_Type
(Etype
(Ptr
)));
4776 Make_Selected_Component
(Loc
,
4777 Prefix
=> Unchecked_Convert_To
(T
, Ptr
),
4779 New_Occurrence_Of
(First_Entity
(T
), Loc
));
4782 Make_Selected_Component
(Loc
,
4783 Prefix
=> Unchecked_Convert_To
(T
, Ptr
),
4785 New_Occurrence_Of
(Next_Entity
(First_Entity
(T
)), Loc
));
4788 Make_Explicit_Dereference
(Loc
,
4791 if Present
(Parameter_Associations
(Call_Node
)) then
4792 Parm
:= Parameter_Associations
(Call_Node
);
4797 Prepend
(Obj
, Parm
);
4799 if Etype
(D_T
) = Standard_Void_Type
then
4801 Make_Procedure_Call_Statement
(Loc
,
4803 Parameter_Associations
=> Parm
);
4806 Make_Function_Call
(Loc
,
4808 Parameter_Associations
=> Parm
);
4811 Set_First_Named_Actual
(Call
, First_Named_Actual
(Call_Node
));
4812 Set_Etype
(Call
, Etype
(D_T
));
4814 -- We do not re-analyze the call to avoid infinite recursion.
4815 -- We analyze separately the prefix and the object, and set
4816 -- the checks on the prefix that would otherwise be emitted
4817 -- when resolving a call.
4819 Rewrite
(Call_Node
, Call
);
4821 Apply_Access_Check
(Nam
);
4828 -- If this is a call to an intrinsic subprogram, then perform the
4829 -- appropriate expansion to the corresponding tree node and we
4830 -- are all done (since after that the call is gone).
4832 -- In the case where the intrinsic is to be processed by the back end,
4833 -- the call to Expand_Intrinsic_Call will do nothing, which is fine,
4834 -- since the idea in this case is to pass the call unchanged. If the
4835 -- intrinsic is an inherited unchecked conversion, and the derived type
4836 -- is the target type of the conversion, we must retain it as the return
4837 -- type of the expression. Otherwise the expansion below, which uses the
4838 -- parent operation, will yield the wrong type.
4840 if Is_Intrinsic_Subprogram
(Subp
) then
4841 Expand_Intrinsic_Call
(Call_Node
, Subp
);
4843 if Nkind
(Call_Node
) = N_Unchecked_Type_Conversion
4844 and then Parent_Subp
/= Orig_Subp
4845 and then Etype
(Parent_Subp
) /= Etype
(Orig_Subp
)
4847 Set_Etype
(Call_Node
, Etype
(Orig_Subp
));
4853 if Ekind
(Subp
) in E_Function | E_Procedure
then
4855 -- We perform a simple optimization on calls for To_Address by
4856 -- replacing them with an unchecked conversion. Not only is this
4857 -- efficient, but it also avoids order of elaboration problems when
4858 -- address clauses are inlined (address expression elaborated at the
4861 -- We perform this optimization regardless of whether we are in the
4862 -- main unit or in a unit in the context of the main unit, to ensure
4863 -- that the generated tree is the same in both cases, for CodePeer
4866 if Is_RTE
(Subp
, RE_To_Address
) then
4868 Unchecked_Convert_To
4869 (RTE
(RE_Address
), Relocate_Node
(First_Actual
(Call_Node
))));
4872 -- A call to a null procedure is replaced by a null statement, but we
4873 -- are not allowed to ignore possible side effects of the call, so we
4874 -- make sure that actuals are evaluated.
4875 -- We also suppress this optimization for GNATcoverage.
4877 elsif Is_Null_Procedure
(Subp
)
4878 and then not Opt
.Suppress_Control_Flow_Optimizations
4880 Actual
:= First_Actual
(Call_Node
);
4881 while Present
(Actual
) loop
4882 Remove_Side_Effects
(Actual
);
4883 Next_Actual
(Actual
);
4886 Rewrite
(Call_Node
, Make_Null_Statement
(Loc
));
4890 -- Handle inlining. No action needed if the subprogram is not inlined
4892 if not Is_Inlined
(Subp
) then
4895 -- Front-end inlining of expression functions (performed also when
4896 -- back-end inlining is enabled).
4898 elsif Is_Inlinable_Expression_Function
(Subp
) then
4900 (Call_Node
, New_Copy
(Expression_Of_Expression_Function
(Subp
)));
4901 Analyze
(Call_Node
);
4904 -- Handle front-end inlining
4906 elsif not Back_End_Inlining
then
4907 Inlined_Subprogram
: declare
4909 Must_Inline
: Boolean := False;
4910 Spec
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
4913 -- Verify that the body to inline has already been seen, and
4914 -- that if the body is in the current unit the inlining does
4915 -- not occur earlier. This avoids order-of-elaboration problems
4918 -- This should be documented in sinfo/einfo ???
4921 or else Nkind
(Spec
) /= N_Subprogram_Declaration
4922 or else No
(Body_To_Inline
(Spec
))
4924 Must_Inline
:= False;
4926 -- If this an inherited function that returns a private type,
4927 -- do not inline if the full view is an unconstrained array,
4928 -- because such calls cannot be inlined.
4930 elsif Present
(Orig_Subp
)
4931 and then Is_Array_Type
(Etype
(Orig_Subp
))
4932 and then not Is_Constrained
(Etype
(Orig_Subp
))
4934 Must_Inline
:= False;
4936 elsif In_Unfrozen_Instance
(Scope
(Subp
)) then
4937 Must_Inline
:= False;
4940 Bod
:= Body_To_Inline
(Spec
);
4942 if (In_Extended_Main_Code_Unit
(Call_Node
)
4943 or else In_Extended_Main_Code_Unit
(Parent
(Call_Node
))
4944 or else Has_Pragma_Inline_Always
(Subp
))
4945 and then (not In_Same_Extended_Unit
(Sloc
(Bod
), Loc
)
4947 Earlier_In_Extended_Unit
(Sloc
(Bod
), Loc
))
4949 Must_Inline
:= True;
4951 -- If we are compiling a package body that is not the main
4952 -- unit, it must be for inlining/instantiation purposes,
4953 -- in which case we inline the call to insure that the same
4954 -- temporaries are generated when compiling the body by
4955 -- itself. Otherwise link errors can occur.
4957 -- If the function being called is itself in the main unit,
4958 -- we cannot inline, because there is a risk of double
4959 -- elaboration and/or circularity: the inlining can make
4960 -- visible a private entity in the body of the main unit,
4961 -- that gigi will see before its sees its proper definition.
4963 elsif not In_Extended_Main_Code_Unit
(Call_Node
)
4964 and then In_Package_Body
4966 Must_Inline
:= not In_Extended_Main_Source_Unit
(Subp
);
4968 -- Inline calls to _Wrapped_Statements when generating C
4970 elsif Modify_Tree_For_C
4971 and then In_Same_Extended_Unit
(Sloc
(Bod
), Loc
)
4972 and then Chars
(Name
(Call_Node
))
4973 = Name_uWrapped_Statements
4975 Must_Inline
:= True;
4980 Expand_Inlined_Call
(Call_Node
, Subp
, Orig_Subp
);
4983 -- Let the back end handle it
4985 Add_Inlined_Body
(Subp
, Call_Node
);
4987 if Front_End_Inlining
4988 and then Nkind
(Spec
) = N_Subprogram_Declaration
4989 and then In_Extended_Main_Code_Unit
(Call_Node
)
4990 and then No
(Body_To_Inline
(Spec
))
4991 and then not Has_Completion
(Subp
)
4992 and then In_Same_Extended_Unit
(Sloc
(Spec
), Loc
)
4995 ("cannot inline& (body not seen yet)?",
4999 end Inlined_Subprogram
;
5001 -- Front-end expansion of simple functions returning unconstrained
5002 -- types (see Check_And_Split_Unconstrained_Function). Note that the
5003 -- case of a simple renaming (Body_To_Inline in N_Entity below, see
5004 -- also Build_Renamed_Body) cannot be expanded here because this may
5005 -- give rise to order-of-elaboration issues for the types of the
5006 -- parameters of the subprogram, if any.
5008 elsif Present
(Unit_Declaration_Node
(Subp
))
5009 and then Nkind
(Unit_Declaration_Node
(Subp
)) =
5010 N_Subprogram_Declaration
5011 and then Present
(Body_To_Inline
(Unit_Declaration_Node
(Subp
)))
5013 Nkind
(Body_To_Inline
(Unit_Declaration_Node
(Subp
))) not in
5016 Expand_Inlined_Call
(Call_Node
, Subp
, Orig_Subp
);
5018 -- Back-end inlining either if optimization is enabled or the call is
5019 -- required to be inlined.
5021 elsif Optimization_Level
> 0
5022 or else Has_Pragma_Inline_Always
(Subp
)
5024 Add_Inlined_Body
(Subp
, Call_Node
);
5028 -- Check for protected subprogram. This is either an intra-object call,
5029 -- or a protected function call. Protected procedure calls are rewritten
5030 -- as entry calls and handled accordingly.
5032 -- In Ada 2005, this may be an indirect call to an access parameter that
5033 -- is an access_to_subprogram. In that case the anonymous type has a
5034 -- scope that is a protected operation, but the call is a regular one.
5035 -- In either case do not expand call if subprogram is eliminated.
5037 Scop
:= Scope
(Subp
);
5039 if Nkind
(Call_Node
) /= N_Entry_Call_Statement
5040 and then Is_Protected_Type
(Scop
)
5041 and then Ekind
(Subp
) /= E_Subprogram_Type
5042 and then not Is_Eliminated
(Subp
)
5044 -- If the call is an internal one, it is rewritten as a call to the
5045 -- corresponding unprotected subprogram.
5047 Expand_Protected_Subprogram_Call
(Call_Node
, Subp
, Scop
);
5050 -- Functions returning controlled objects need special attention. If
5051 -- the return type is limited, then the context is initialization and
5052 -- different processing applies. If the call is to a protected function,
5053 -- the expansion above will call Expand_Call recursively. Otherwise the
5054 -- function call is transformed into a reference to the result that has
5055 -- been built either on the primary or the secondary stack.
5057 if Needs_Finalization
(Etype
(Subp
)) then
5058 if not Is_Build_In_Place_Function_Call
(Call_Node
)
5060 (No
(First_Formal
(Subp
))
5062 not Is_Concurrent_Record_Type
(Etype
(First_Formal
(Subp
))))
5064 Expand_Ctrl_Function_Call
5065 (Call_Node
, Needs_Secondary_Stack
(Etype
(Subp
)));
5067 -- Build-in-place function calls which appear in anonymous contexts
5068 -- need a transient scope to ensure the proper finalization of the
5069 -- intermediate result after its use.
5071 elsif Is_Build_In_Place_Function_Call
(Call_Node
)
5072 and then Nkind
(Parent
(Unqual_Conv
(Call_Node
))) in
5073 N_Attribute_Reference
5075 | N_Indexed_Component
5076 | N_Object_Renaming_Declaration
5077 | N_Procedure_Call_Statement
5078 | N_Selected_Component
5081 (Ekind
(Current_Scope
) /= E_Loop
5082 or else Nkind
(Parent
(Call_Node
)) /= N_Function_Call
5084 Is_Build_In_Place_Function_Call
(Parent
(Call_Node
)))
5086 Establish_Transient_Scope
5087 (Call_Node
, Needs_Secondary_Stack
(Etype
(Subp
)));
5090 end Expand_Call_Helper
;
5092 -------------------------------
5093 -- Expand_Ctrl_Function_Call --
5094 -------------------------------
5096 procedure Expand_Ctrl_Function_Call
(N
: Node_Id
; Use_Sec_Stack
: Boolean)
5098 Par
: constant Node_Id
:= Parent
(N
);
5100 function Is_Element_Reference
(N
: Node_Id
) return Boolean;
5101 -- Determine whether node N denotes a reference to an Ada 2012 container
5104 --------------------------
5105 -- Is_Element_Reference --
5106 --------------------------
5108 function Is_Element_Reference
(N
: Node_Id
) return Boolean is
5109 Ref
: constant Node_Id
:= Original_Node
(N
);
5112 -- Analysis marks an element reference by setting the generalized
5113 -- indexing attribute of an indexed component before the component
5114 -- is rewritten into a function call.
5117 Nkind
(Ref
) = N_Indexed_Component
5118 and then Present
(Generalized_Indexing
(Ref
));
5119 end Is_Element_Reference
;
5121 -- Start of processing for Expand_Ctrl_Function_Call
5124 -- Optimization: if the returned value is returned again, then no need
5125 -- to copy/readjust/finalize, we can just pass the value through (see
5126 -- Expand_N_Simple_Return_Statement), and thus no attachment is needed.
5128 if Nkind
(Par
) = N_Simple_Return_Statement
then
5132 -- Another optimization: if the returned value is used to initialize an
5133 -- object, then no need to copy/readjust/finalize, we can initialize it
5134 -- in place. However, if the call returns on the secondary stack or this
5135 -- is a special return object, then we need the expansion because we'll
5136 -- be renaming the temporary as the (permanent) object.
5138 if Nkind
(Par
) = N_Object_Declaration
5139 and then not Use_Sec_Stack
5140 and then not Is_Special_Return_Object
(Defining_Entity
(Par
))
5145 -- Resolution is now finished, make sure we don't start analysis again
5146 -- because of the duplication.
5150 -- Apply the transformation, unless it was already applied manually
5152 if Nkind
(Par
) /= N_Reference
then
5153 Remove_Side_Effects
(N
);
5156 -- The side effect removal of the function call produced a temporary.
5157 -- When the context is a case expression, if expression, or expression
5158 -- with actions, the lifetime of the temporary must be extended to match
5159 -- that of the context. Otherwise the function result will be finalized
5160 -- too early and affect the result of the expression. To prevent this
5161 -- unwanted effect, the temporary should not be considered for clean up
5162 -- actions by the general finalization machinery.
5164 -- Exception to this rule are references to Ada 2012 container elements.
5165 -- Such references must be finalized at the end of each iteration of the
5166 -- related quantified expression, otherwise the container will remain
5169 if Nkind
(N
) = N_Explicit_Dereference
5170 and then Within_Case_Or_If_Expression
(N
)
5171 and then not Is_Element_Reference
(N
)
5173 Set_Is_Ignored_Transient
(Entity
(Prefix
(N
)));
5175 end Expand_Ctrl_Function_Call
;
5177 ----------------------------------------
5178 -- Expand_N_Extended_Return_Statement --
5179 ----------------------------------------
5181 -- If there is a Handled_Statement_Sequence, we rewrite this:
5183 -- return Result : T := <expression> do
5184 -- <handled_seq_of_stms>
5190 -- Result : T := <expression>;
5192 -- <handled_seq_of_stms>
5196 -- Otherwise (no Handled_Statement_Sequence), we rewrite this:
5198 -- return Result : T := <expression>;
5202 -- return <expression>;
5204 -- unless it's build-in-place or there's no <expression>, in which case
5208 -- Result : T := <expression>;
5213 -- Note that this case could have been written by the user as an extended
5214 -- return statement, or could have been transformed to this from a simple
5215 -- return statement.
5217 -- That is, we need to have a reified return object if there are statements
5218 -- (which might refer to it) or if we're doing build-in-place (so we can
5219 -- set its address to the final resting place or if there is no expression
5220 -- (in which case default initial values might need to be set)).
5222 procedure Expand_N_Extended_Return_Statement
(N
: Node_Id
) is
5223 Loc
: constant Source_Ptr
:= Sloc
(N
);
5224 Func_Id
: constant Entity_Id
:=
5225 Return_Applies_To
(Return_Statement_Entity
(N
));
5226 Is_BIP_Func
: constant Boolean :=
5227 Is_Build_In_Place_Function
(Func_Id
);
5228 Ret_Obj_Id
: constant Entity_Id
:=
5229 First_Entity
(Return_Statement_Entity
(N
));
5230 Ret_Obj_Decl
: constant Node_Id
:= Parent
(Ret_Obj_Id
);
5231 Ret_Typ
: constant Entity_Id
:= Etype
(Func_Id
);
5233 function Move_Activation_Chain
(Func_Id
: Entity_Id
) return Node_Id
;
5234 -- Construct a call to System.Tasking.Stages.Move_Activation_Chain
5236 -- From current activation chain
5237 -- To activation chain passed in by the caller
5238 -- New_Master master passed in by the caller
5240 -- Func_Id is the entity of the function where the extended return
5241 -- statement appears.
5243 ---------------------------
5244 -- Move_Activation_Chain --
5245 ---------------------------
5247 function Move_Activation_Chain
(Func_Id
: Entity_Id
) return Node_Id
is
5250 Make_Procedure_Call_Statement
(Loc
,
5252 New_Occurrence_Of
(RTE
(RE_Move_Activation_Chain
), Loc
),
5254 Parameter_Associations
=> New_List
(
5258 Make_Attribute_Reference
(Loc
,
5259 Prefix
=> Make_Identifier
(Loc
, Name_uChain
),
5260 Attribute_Name
=> Name_Unrestricted_Access
),
5262 -- Destination chain
5265 (Build_In_Place_Formal
(Func_Id
, BIP_Activation_Chain
), Loc
),
5270 (Build_In_Place_Formal
(Func_Id
, BIP_Task_Master
), Loc
)));
5271 end Move_Activation_Chain
;
5278 Stmts
: List_Id
:= No_List
;
5280 Return_Stmt
: Node_Id
:= Empty
;
5281 -- Force initialization to facilitate static analysis
5283 -- Start of processing for Expand_N_Extended_Return_Statement
5286 -- Given that functionality of interface thunks is simple (just displace
5287 -- the pointer to the object) they are always handled by means of
5288 -- simple return statements.
5290 pragma Assert
(not Is_Thunk
(Current_Subprogram
));
5292 if Nkind
(Ret_Obj_Decl
) = N_Object_Declaration
then
5293 Exp
:= Expression
(Ret_Obj_Decl
);
5295 -- Assert that if F says "return R : T := G(...) do..."
5296 -- then F and G are both b-i-p, or neither b-i-p.
5298 if Present
(Exp
) and then Nkind
(Exp
) = N_Function_Call
then
5299 pragma Assert
(Ekind
(Current_Subprogram
) = E_Function
);
5301 (Is_Build_In_Place_Function
(Current_Subprogram
) =
5302 Is_Build_In_Place_Function_Call
(Exp
));
5310 HSS
:= Handled_Statement_Sequence
(N
);
5312 -- If the returned object needs finalization actions, the function must
5313 -- perform the appropriate cleanup should it fail to return. The state
5314 -- of the function itself is tracked through a flag which is coupled
5315 -- with the scope finalizer. There is one flag per each return object
5316 -- in case of multiple returns.
5318 if Is_BIP_Func
and then Needs_Finalization
(Etype
(Ret_Obj_Id
)) then
5320 Flag_Decl
: Node_Id
;
5321 Flag_Id
: Entity_Id
;
5325 -- Recover the function body
5327 Func_Bod
:= Unit_Declaration_Node
(Func_Id
);
5329 if Nkind
(Func_Bod
) = N_Subprogram_Declaration
then
5330 Func_Bod
:= Parent
(Parent
(Corresponding_Body
(Func_Bod
)));
5333 if Nkind
(Func_Bod
) = N_Function_Specification
then
5334 Func_Bod
:= Parent
(Func_Bod
); -- one more level for child units
5337 pragma Assert
(Nkind
(Func_Bod
) = N_Subprogram_Body
);
5339 -- Create a flag to track the function state
5341 Flag_Id
:= Make_Temporary
(Loc
, 'F');
5342 Set_Status_Flag_Or_Transient_Decl
(Ret_Obj_Id
, Flag_Id
);
5344 -- Insert the flag at the beginning of the function declarations,
5346 -- Fnn : Boolean := False;
5349 Make_Object_Declaration
(Loc
,
5350 Defining_Identifier
=> Flag_Id
,
5351 Object_Definition
=>
5352 New_Occurrence_Of
(Standard_Boolean
, Loc
),
5354 New_Occurrence_Of
(Standard_False
, Loc
));
5356 Prepend_To
(Declarations
(Func_Bod
), Flag_Decl
);
5357 Analyze
(Flag_Decl
);
5361 -- Build a simple_return_statement that returns the return object when
5362 -- there is a statement sequence, or no expression, or the analysis of
5363 -- the return object declaration generated extra actions, or the result
5364 -- will be built in place. Note however that we currently do this for
5365 -- all composite cases, even though they are not built in place.
5369 or else List_Length
(Return_Object_Declarations
(N
)) > 1
5370 or else Is_Composite_Type
(Ret_Typ
)
5375 -- If the extended return has a handled statement sequence, then wrap
5376 -- it in a block and use the block as the first statement.
5380 Make_Block_Statement
(Loc
,
5381 Declarations
=> New_List
,
5382 Handled_Statement_Sequence
=> HSS
));
5385 -- If the result type contains tasks, we call Move_Activation_Chain.
5386 -- Later, the cleanup code will call Complete_Master, which will
5387 -- terminate any unactivated tasks belonging to the return statement
5388 -- master. But Move_Activation_Chain updates their master to be that
5389 -- of the caller, so they will not be terminated unless the return
5390 -- statement completes unsuccessfully due to exception, abort, goto,
5391 -- or exit. As a formality, we test whether the function requires the
5392 -- result to be built in place, though that's necessarily true for
5393 -- the case of result types with task parts.
5395 if Is_BIP_Func
and then Has_Task
(Ret_Typ
) then
5397 -- The return expression is an aggregate for a complex type which
5398 -- contains tasks. This particular case is left unexpanded since
5399 -- the regular expansion would insert all temporaries and
5400 -- initialization code in the wrong block.
5402 if Nkind
(Exp
) = N_Aggregate
then
5403 Expand_N_Aggregate
(Exp
);
5406 -- Do not move the activation chain if the return object does not
5409 if Has_Task
(Etype
(Ret_Obj_Id
)) then
5410 Append_To
(Stmts
, Move_Activation_Chain
(Func_Id
));
5414 -- Update the state of the function right before the object is
5417 if Is_BIP_Func
and then Needs_Finalization
(Etype
(Ret_Obj_Id
)) then
5419 Flag_Id
: constant Entity_Id
:=
5420 Status_Flag_Or_Transient_Decl
(Ret_Obj_Id
);
5427 Make_Assignment_Statement
(Loc
,
5428 Name
=> New_Occurrence_Of
(Flag_Id
, Loc
),
5429 Expression
=> New_Occurrence_Of
(Standard_True
, Loc
)));
5433 HSS
:= Make_Handled_Sequence_Of_Statements
(Loc
, Stmts
);
5436 -- Case where we build a return statement block
5438 if Present
(HSS
) then
5440 Make_Block_Statement
(Loc
,
5441 Declarations
=> Return_Object_Declarations
(N
),
5442 Handled_Statement_Sequence
=> HSS
);
5444 -- We set the entity of the new block statement to be that of the
5445 -- return statement. This is necessary so that various fields, such
5446 -- as Finalization_Chain_Entity carry over from the return statement
5447 -- to the block. Note that this block is unusual, in that its entity
5448 -- is an E_Return_Statement rather than an E_Block.
5451 (Result
, New_Occurrence_Of
(Return_Statement_Entity
(N
), Loc
));
5453 -- Build a simple_return_statement that returns the return object
5456 Make_Simple_Return_Statement
(Loc
,
5457 Expression
=> New_Occurrence_Of
(Ret_Obj_Id
, Loc
));
5458 Append_To
(Stmts
, Return_Stmt
);
5460 -- Case where we do not need to build a block. But we're about to drop
5461 -- Return_Object_Declarations on the floor, so assert that it contains
5462 -- only the return object declaration.
5464 else pragma Assert
(List_Length
(Return_Object_Declarations
(N
)) = 1);
5466 -- Build simple_return_statement that returns the expression directly
5468 Return_Stmt
:= Make_Simple_Return_Statement
(Loc
, Expression
=> Exp
);
5469 Result
:= Return_Stmt
;
5472 -- Set the flag to prevent infinite recursion
5474 Set_Comes_From_Extended_Return_Statement
(Return_Stmt
);
5475 Set_Return_Statement
(Ret_Obj_Id
, Return_Stmt
);
5477 Rewrite
(N
, Result
);
5479 -- AI12-043: The checks of 6.5(8.1/3) and 6.5(21/3) are made immediately
5480 -- before an object is returned. A predicate that applies to the return
5481 -- subtype is checked immediately before an object is returned.
5484 end Expand_N_Extended_Return_Statement
;
5486 ----------------------------
5487 -- Expand_N_Function_Call --
5488 ----------------------------
5490 procedure Expand_N_Function_Call
(N
: Node_Id
) is
5493 end Expand_N_Function_Call
;
5495 ---------------------------------------
5496 -- Expand_N_Procedure_Call_Statement --
5497 ---------------------------------------
5499 procedure Expand_N_Procedure_Call_Statement
(N
: Node_Id
) is
5502 end Expand_N_Procedure_Call_Statement
;
5504 ------------------------------------
5505 -- Expand_N_Return_When_Statement --
5506 ------------------------------------
5508 procedure Expand_N_Return_When_Statement
(N
: Node_Id
) is
5509 Loc
: constant Source_Ptr
:= Sloc
(N
);
5512 Make_If_Statement
(Loc
,
5513 Condition
=> Condition
(N
),
5514 Then_Statements
=> New_List
(
5515 Make_Simple_Return_Statement
(Loc
,
5516 Expression
=> Expression
(N
)))));
5519 end Expand_N_Return_When_Statement
;
5521 --------------------------------------
5522 -- Expand_N_Simple_Return_Statement --
5523 --------------------------------------
5525 procedure Expand_N_Simple_Return_Statement
(N
: Node_Id
) is
5527 -- Defend against previous errors (i.e. the return statement calls a
5528 -- function that is not available in configurable runtime).
5530 if Present
(Expression
(N
))
5531 and then Nkind
(Expression
(N
)) = N_Empty
5533 Check_Error_Detected
;
5537 -- Distinguish the function and non-function cases:
5539 case Ekind
(Return_Applies_To
(Return_Statement_Entity
(N
))) is
5541 | E_Generic_Function
5543 Expand_Simple_Function_Return
(N
);
5547 | E_Generic_Procedure
5549 | E_Return_Statement
5551 Expand_Non_Function_Return
(N
);
5554 raise Program_Error
;
5558 when RE_Not_Available
=>
5560 end Expand_N_Simple_Return_Statement
;
5562 ------------------------------
5563 -- Expand_N_Subprogram_Body --
5564 ------------------------------
5566 -- Add dummy push/pop label nodes at start and end to clear any local
5567 -- exception indications if local-exception-to-goto optimization is active.
5569 -- Add return statement if last statement in body is not a return statement
5570 -- (this makes things easier on Gigi which does not want to have to handle
5571 -- a missing return).
5573 -- Add call to Activate_Tasks if body is a task activator
5575 -- Deal with possible detection of infinite recursion
5577 -- Eliminate body completely if convention stubbed
5579 -- Encode entity names within body, since we will not need to reference
5580 -- these entities any longer in the front end.
5582 -- Initialize scalar out parameters if Initialize/Normalize_Scalars
5584 -- Reset Pure indication if any parameter has root type System.Address
5585 -- or has any parameters of limited types, where limited means that the
5586 -- run-time view is limited (i.e. the full type is limited).
5590 procedure Expand_N_Subprogram_Body
(N
: Node_Id
) is
5591 Body_Id
: constant Entity_Id
:= Defining_Entity
(N
);
5592 HSS
: constant Node_Id
:= Handled_Statement_Sequence
(N
);
5593 Loc
: constant Source_Ptr
:= Sloc
(N
);
5595 procedure Add_Return
(Spec_Id
: Entity_Id
; Stmts
: List_Id
);
5596 -- Append a return statement to the statement sequence Stmts if the last
5597 -- statement is not already a return or a goto statement. Note that the
5598 -- latter test is not critical, it does not matter if we add a few extra
5599 -- returns, since they get eliminated anyway later on. Spec_Id denotes
5600 -- the corresponding spec of the subprogram body.
5606 procedure Add_Return
(Spec_Id
: Entity_Id
; Stmts
: List_Id
) is
5607 Last_Stmt
: Node_Id
;
5612 -- Get last statement, ignoring any Pop_xxx_Label nodes, which are
5613 -- not relevant in this context since they are not executable.
5615 Last_Stmt
:= Last
(Stmts
);
5616 while Nkind
(Last_Stmt
) in N_Pop_xxx_Label
loop
5620 -- Now insert return unless last statement is a transfer
5622 if not Is_Transfer
(Last_Stmt
) then
5624 -- The source location for the return is the end label of the
5625 -- procedure if present. Otherwise use the sloc of the last
5626 -- statement in the list. If the list comes from a generated
5627 -- exception handler and we are not debugging generated code,
5628 -- all the statements within the handler are made invisible
5631 if Nkind
(Parent
(Stmts
)) = N_Exception_Handler
5632 and then not Comes_From_Source
(Parent
(Stmts
))
5634 Loc
:= Sloc
(Last_Stmt
);
5635 elsif Present
(End_Label
(HSS
)) then
5636 Loc
:= Sloc
(End_Label
(HSS
));
5638 Loc
:= Sloc
(Last_Stmt
);
5641 -- Append return statement, and set analyzed manually. We can't
5642 -- call Analyze on this return since the scope is wrong.
5644 -- Note: it almost works to push the scope and then do the Analyze
5645 -- call, but something goes wrong in some weird cases and it is
5646 -- not worth worrying about ???
5648 Stmt
:= Make_Simple_Return_Statement
(Loc
);
5650 -- The return statement is handled properly, and the call to the
5651 -- postcondition, inserted below, does not require information
5652 -- from the body either. However, that call is analyzed in the
5653 -- enclosing scope, and an elaboration check might improperly be
5654 -- added to it. A guard in Sem_Elab is needed to prevent that
5655 -- spurious check, see Check_Elab_Call.
5657 Append_To
(Stmts
, Stmt
);
5658 Set_Analyzed
(Stmt
);
5660 -- Ada 2022 (AI12-0279): append the call to 'Yield unless this is
5661 -- a generic subprogram (since in such case it will be added to
5662 -- the instantiations).
5664 if Has_Yield_Aspect
(Spec_Id
)
5665 and then Ekind
(Spec_Id
) /= E_Generic_Procedure
5666 and then RTE_Available
(RE_Yield
)
5668 Insert_Action
(Stmt
,
5669 Make_Procedure_Call_Statement
(Loc
,
5670 New_Occurrence_Of
(RTE
(RE_Yield
), Loc
)));
5679 Spec_Id
: Entity_Id
;
5681 -- Start of processing for Expand_N_Subprogram_Body
5684 if Present
(Corresponding_Spec
(N
)) then
5685 Spec_Id
:= Corresponding_Spec
(N
);
5690 -- If this is a Pure function which has any parameters whose root type
5691 -- is System.Address, reset the Pure indication.
5692 -- This check is also performed when the subprogram is frozen, but we
5693 -- repeat it on the body so that the indication is consistent, and so
5694 -- it applies as well to bodies without separate specifications.
5696 if Is_Pure
(Spec_Id
)
5697 and then Is_Subprogram
(Spec_Id
)
5698 and then not Has_Pragma_Pure_Function
(Spec_Id
)
5700 Check_Function_With_Address_Parameter
(Spec_Id
);
5702 if Spec_Id
/= Body_Id
then
5703 Set_Is_Pure
(Body_Id
, Is_Pure
(Spec_Id
));
5707 -- Set L to either the list of declarations if present, or to the list
5708 -- of statements if no declarations are present. This is used to insert
5709 -- new stuff at the start.
5711 if Is_Non_Empty_List
(Declarations
(N
)) then
5712 L
:= Declarations
(N
);
5714 L
:= Statements
(HSS
);
5717 -- If local-exception-to-goto optimization active, insert dummy push
5718 -- statements at start, and dummy pop statements at end, but inhibit
5719 -- this if we have No_Exception_Handlers, since they are useless and
5720 -- interfere with analysis, e.g. by CodePeer. We also don't need these
5721 -- if we're unnesting subprograms because the only purpose of these
5722 -- nodes is to ensure we don't set a label in one subprogram and branch
5723 -- to it in another.
5725 if (Debug_Flag_Dot_G
5726 or else Restriction_Active
(No_Exception_Propagation
))
5727 and then not Restriction_Active
(No_Exception_Handlers
)
5728 and then not CodePeer_Mode
5729 and then not Unnest_Subprogram_Mode
5730 and then Is_Non_Empty_List
(L
)
5733 FS
: constant Node_Id
:= First
(L
);
5734 FL
: constant Source_Ptr
:= Sloc
(FS
);
5739 -- LS points to either last statement, if statements are present
5740 -- or to the last declaration if there are no statements present.
5741 -- It is the node after which the pop's are generated.
5743 if Is_Non_Empty_List
(Statements
(HSS
)) then
5744 LS
:= Last
(Statements
(HSS
));
5751 Insert_List_Before_And_Analyze
(FS
, New_List
(
5752 Make_Push_Constraint_Error_Label
(FL
),
5753 Make_Push_Program_Error_Label
(FL
),
5754 Make_Push_Storage_Error_Label
(FL
)));
5756 Insert_List_After_And_Analyze
(LS
, New_List
(
5757 Make_Pop_Constraint_Error_Label
(LL
),
5758 Make_Pop_Program_Error_Label
(LL
),
5759 Make_Pop_Storage_Error_Label
(LL
)));
5763 -- Initialize any scalar OUT args if Initialize/Normalize_Scalars
5765 if Init_Or_Norm_Scalars
and then Is_Subprogram
(Spec_Id
) then
5771 -- Loop through formals
5773 F
:= First_Formal
(Spec_Id
);
5774 while Present
(F
) loop
5775 if Is_Scalar_Type
(Etype
(F
))
5776 and then Ekind
(F
) = E_Out_Parameter
5778 Check_Restriction
(No_Default_Initialization
, F
);
5780 -- Insert the initialization. We turn off validity checks
5781 -- for this assignment, since we do not want any check on
5782 -- the initial value itself (which may well be invalid).
5783 -- Predicate checks are disabled as well (RM 6.4.1 (13/3))
5786 Make_Assignment_Statement
(Loc
,
5787 Name
=> New_Occurrence_Of
(F
, Loc
),
5788 Expression
=> Get_Simple_Init_Val
(Etype
(F
), N
));
5789 Set_Suppress_Assignment_Checks
(A
);
5791 Insert_Before_And_Analyze
(First
(L
),
5792 A
, Suppress
=> Validity_Check
);
5800 -- Clear out statement list for stubbed procedure
5802 if Present
(Corresponding_Spec
(N
)) then
5803 Set_Elaboration_Flag
(N
, Spec_Id
);
5805 if Convention
(Spec_Id
) = Convention_Stubbed
5806 or else Is_Eliminated
(Spec_Id
)
5808 Set_Declarations
(N
, Empty_List
);
5809 Set_Handled_Statement_Sequence
(N
,
5810 Make_Handled_Sequence_Of_Statements
(Loc
,
5811 Statements
=> New_List
(Make_Null_Statement
(Loc
))));
5817 -- Create a set of discriminals for the next protected subprogram body
5819 if Is_List_Member
(N
)
5820 and then Present
(Parent
(List_Containing
(N
)))
5821 and then Nkind
(Parent
(List_Containing
(N
))) = N_Protected_Body
5822 and then Present
(Next_Protected_Operation
(N
))
5824 Set_Discriminals
(Parent
(Base_Type
(Scope
(Spec_Id
))));
5827 -- Returns_By_Ref flag is normally set when the subprogram is frozen but
5828 -- subprograms with no specs are not frozen.
5830 Compute_Returns_By_Ref
(Spec_Id
);
5832 -- For a procedure, we add a return for all possible syntactic ends of
5835 if Ekind
(Spec_Id
) in E_Procedure | E_Generic_Procedure
then
5836 Add_Return
(Spec_Id
, Statements
(HSS
));
5838 if Present
(Exception_Handlers
(HSS
)) then
5839 Except_H
:= First_Non_Pragma
(Exception_Handlers
(HSS
));
5840 while Present
(Except_H
) loop
5841 Add_Return
(Spec_Id
, Statements
(Except_H
));
5842 Next_Non_Pragma
(Except_H
);
5846 -- For a function, we must deal with the case where there is at least
5847 -- one missing return. What we do is to wrap the entire body of the
5848 -- function in a block:
5861 -- raise Program_Error;
5864 -- This approach is necessary because the raise must be signalled to the
5865 -- caller, not handled by any local handler (RM 6.4(11)).
5867 -- Note: we do not need to analyze the constructed sequence here, since
5868 -- it has no handler, and an attempt to analyze the handled statement
5869 -- sequence twice is risky in various ways (e.g. the issue of expanding
5870 -- cleanup actions twice).
5872 elsif Has_Missing_Return
(Spec_Id
) then
5874 Hloc
: constant Source_Ptr
:= Sloc
(HSS
);
5875 Blok
: constant Node_Id
:=
5876 Make_Block_Statement
(Hloc
,
5877 Handled_Statement_Sequence
=> HSS
);
5878 Rais
: constant Node_Id
:=
5879 Make_Raise_Program_Error
(Hloc
,
5880 Reason
=> PE_Missing_Return
);
5883 Set_Handled_Statement_Sequence
(N
,
5884 Make_Handled_Sequence_Of_Statements
(Hloc
,
5885 Statements
=> New_List
(Blok
, Rais
)));
5887 Push_Scope
(Spec_Id
);
5894 -- If subprogram contains a parameterless recursive call, then we may
5895 -- have an infinite recursion, so see if we can generate code to check
5896 -- for this possibility if storage checks are not suppressed.
5898 if Ekind
(Spec_Id
) = E_Procedure
5899 and then Has_Recursive_Call
(Spec_Id
)
5900 and then not Storage_Checks_Suppressed
(Spec_Id
)
5902 Detect_Infinite_Recursion
(N
, Spec_Id
);
5905 -- Set to encode entity names in package body before gigi is called
5907 Qualify_Entity_Names
(N
);
5909 -- If the body belongs to a nonabstract library-level source primitive
5910 -- of a tagged type, install an elaboration check which ensures that a
5911 -- dispatching call targeting the primitive will not execute the body
5912 -- without it being previously elaborated.
5914 Install_Primitive_Elaboration_Check
(N
);
5915 end Expand_N_Subprogram_Body
;
5917 -----------------------------------
5918 -- Expand_N_Subprogram_Body_Stub --
5919 -----------------------------------
5921 procedure Expand_N_Subprogram_Body_Stub
(N
: Node_Id
) is
5925 if Present
(Corresponding_Body
(N
)) then
5926 Bod
:= Unit_Declaration_Node
(Corresponding_Body
(N
));
5928 -- The body may have been expanded already when it is analyzed
5929 -- through the subunit node. Do no expand again: it interferes
5930 -- with the construction of unnesting tables when generating C.
5932 if not Analyzed
(Bod
) then
5933 Expand_N_Subprogram_Body
(Bod
);
5936 -- Add full qualification to entities that may be created late
5937 -- during unnesting.
5939 Qualify_Entity_Names
(N
);
5941 end Expand_N_Subprogram_Body_Stub
;
5943 -------------------------------------
5944 -- Expand_N_Subprogram_Declaration --
5945 -------------------------------------
5947 -- If the declaration appears within a protected body, it is a private
5948 -- operation of the protected type. We must create the corresponding
5949 -- protected subprogram an associated formals. For a normal protected
5950 -- operation, this is done when expanding the protected type declaration.
5952 -- If the declaration is for a null procedure, emit null body
5954 procedure Expand_N_Subprogram_Declaration
(N
: Node_Id
) is
5955 Loc
: constant Source_Ptr
:= Sloc
(N
);
5956 Subp
: constant Entity_Id
:= Defining_Entity
(N
);
5960 Scop
: constant Entity_Id
:= Scope
(Subp
);
5962 Prot_Decl
: Node_Id
;
5963 Prot_Id
: Entity_Id
;
5967 -- Deal with case of protected subprogram. Do not generate protected
5968 -- operation if operation is flagged as eliminated.
5970 if Is_List_Member
(N
)
5971 and then Present
(Parent
(List_Containing
(N
)))
5972 and then Nkind
(Parent
(List_Containing
(N
))) = N_Protected_Body
5973 and then Is_Protected_Type
(Scop
)
5975 if No
(Protected_Body_Subprogram
(Subp
))
5976 and then not Is_Eliminated
(Subp
)
5979 Make_Subprogram_Declaration
(Loc
,
5981 Build_Protected_Sub_Specification
5982 (N
, Scop
, Unprotected_Mode
));
5984 -- The protected subprogram is declared outside of the protected
5985 -- body. Given that the body has frozen all entities so far, we
5986 -- analyze the subprogram and perform freezing actions explicitly.
5987 -- including the generation of an explicit freeze node, to ensure
5988 -- that gigi has the proper order of elaboration.
5989 -- If the body is a subunit, the insertion point is before the
5990 -- stub in the parent.
5992 Prot_Bod
:= Parent
(List_Containing
(N
));
5994 if Nkind
(Parent
(Prot_Bod
)) = N_Subunit
then
5995 Prot_Bod
:= Corresponding_Stub
(Parent
(Prot_Bod
));
5998 Insert_Before
(Prot_Bod
, Prot_Decl
);
5999 Prot_Id
:= Defining_Unit_Name
(Specification
(Prot_Decl
));
6000 Set_Has_Delayed_Freeze
(Prot_Id
);
6002 Push_Scope
(Scope
(Scop
));
6003 Analyze
(Prot_Decl
);
6004 Freeze_Before
(N
, Prot_Id
);
6005 Set_Protected_Body_Subprogram
(Subp
, Prot_Id
);
6009 -- Ada 2005 (AI-348): Generate body for a null procedure. In most
6010 -- cases this is superfluous because calls to it will be automatically
6011 -- inlined, but we definitely need the body if preconditions for the
6012 -- procedure are present, or if performing coverage analysis.
6014 elsif Nkind
(Specification
(N
)) = N_Procedure_Specification
6015 and then Null_Present
(Specification
(N
))
6018 Bod
: constant Node_Id
:= Body_To_Inline
(N
);
6021 Set_Has_Completion
(Subp
, False);
6022 Append_Freeze_Action
(Subp
, Bod
);
6024 -- The body now contains raise statements, so calls to it will
6027 Set_Is_Inlined
(Subp
, False);
6031 -- When generating C code, transform a function that returns a
6032 -- constrained array type into a procedure with an out parameter
6033 -- that carries the return value.
6035 -- We skip this transformation for unchecked conversions, since they
6036 -- are not needed by the C generator (and this also produces cleaner
6039 Typ
:= Get_Fullest_View
(Etype
(Subp
));
6041 if Transform_Function_Array
6042 and then Nkind
(Specification
(N
)) = N_Function_Specification
6043 and then Is_Array_Type
(Typ
)
6044 and then Is_Constrained
(Typ
)
6045 and then not Is_Unchecked_Conversion_Instance
(Subp
)
6047 Build_Procedure_Form
(N
);
6049 end Expand_N_Subprogram_Declaration
;
6051 --------------------------------
6052 -- Expand_Non_Function_Return --
6053 --------------------------------
6055 procedure Expand_Non_Function_Return
(N
: Node_Id
) is
6056 pragma Assert
(No
(Expression
(N
)));
6058 Loc
: constant Source_Ptr
:= Sloc
(N
);
6059 Scope_Id
: Entity_Id
:= Return_Applies_To
(Return_Statement_Entity
(N
));
6060 Kind
: constant Entity_Kind
:= Ekind
(Scope_Id
);
6063 Goto_Stat
: Node_Id
;
6067 -- Ada 2022 (AI12-0279)
6069 if Has_Yield_Aspect
(Scope_Id
)
6070 and then RTE_Available
(RE_Yield
)
6073 Make_Procedure_Call_Statement
(Loc
,
6074 New_Occurrence_Of
(RTE
(RE_Yield
), Loc
)));
6077 -- If it is a return from a procedure do no extra steps
6079 if Kind
= E_Procedure
or else Kind
= E_Generic_Procedure
then
6082 -- If it is a nested return within an extended one, replace it with a
6083 -- return of the previously declared return object.
6085 elsif Kind
= E_Return_Statement
then
6087 Make_Simple_Return_Statement
(Loc
,
6089 New_Occurrence_Of
(First_Entity
(Scope_Id
), Loc
)));
6090 Set_Comes_From_Extended_Return_Statement
(N
);
6091 Set_Return_Statement_Entity
(N
, Scope_Id
);
6092 Expand_Simple_Function_Return
(N
);
6096 pragma Assert
(Is_Entry
(Scope_Id
));
6098 -- Look at the enclosing block to see whether the return is from an
6099 -- accept statement or an entry body.
6101 for J
in reverse 0 .. Scope_Stack
.Last
loop
6102 Scope_Id
:= Scope_Stack
.Table
(J
).Entity
;
6103 exit when Is_Concurrent_Type
(Scope_Id
);
6106 -- If it is a return from accept statement it is expanded as call to
6107 -- RTS Complete_Rendezvous and a goto to the end of the accept body.
6109 -- (cf : Expand_N_Accept_Statement, Expand_N_Selective_Accept,
6110 -- Expand_N_Accept_Alternative in exp_ch9.adb)
6112 if Is_Task_Type
(Scope_Id
) then
6115 Make_Procedure_Call_Statement
(Loc
,
6116 Name
=> New_Occurrence_Of
(RTE
(RE_Complete_Rendezvous
), Loc
));
6117 Insert_Before
(N
, Call
);
6118 -- why not insert actions here???
6121 Acc_Stat
:= Parent
(N
);
6122 while Nkind
(Acc_Stat
) /= N_Accept_Statement
loop
6123 Acc_Stat
:= Parent
(Acc_Stat
);
6126 Lab_Node
:= Last
(Statements
6127 (Handled_Statement_Sequence
(Acc_Stat
)));
6129 Goto_Stat
:= Make_Goto_Statement
(Loc
,
6130 Name
=> New_Occurrence_Of
6131 (Entity
(Identifier
(Lab_Node
)), Loc
));
6133 Set_Analyzed
(Goto_Stat
);
6135 Rewrite
(N
, Goto_Stat
);
6138 -- If it is a return from an entry body, put a Complete_Entry_Body call
6139 -- in front of the return.
6141 elsif Is_Protected_Type
(Scope_Id
) then
6143 Make_Procedure_Call_Statement
(Loc
,
6145 New_Occurrence_Of
(RTE
(RE_Complete_Entry_Body
), Loc
),
6146 Parameter_Associations
=> New_List
(
6147 Make_Attribute_Reference
(Loc
,
6150 (Find_Protection_Object
(Current_Scope
), Loc
),
6151 Attribute_Name
=> Name_Unchecked_Access
)));
6153 Insert_Before
(N
, Call
);
6156 end Expand_Non_Function_Return
;
6158 ---------------------------------------
6159 -- Expand_Protected_Object_Reference --
6160 ---------------------------------------
6162 function Expand_Protected_Object_Reference
6164 Scop
: Entity_Id
) return Node_Id
6166 Loc
: constant Source_Ptr
:= Sloc
(N
);
6173 Rec
:= Make_Identifier
(Loc
, Name_uObject
);
6174 Set_Etype
(Rec
, Corresponding_Record_Type
(Scop
));
6176 -- Find enclosing protected operation, and retrieve its first parameter,
6177 -- which denotes the enclosing protected object. If the enclosing
6178 -- operation is an entry, we are immediately within the protected body,
6179 -- and we can retrieve the object from the service entries procedure. A
6180 -- barrier function has the same signature as an entry. A barrier
6181 -- function is compiled within the protected object, but unlike
6182 -- protected operations its never needs locks, so that its protected
6183 -- body subprogram points to itself.
6185 Proc
:= Current_Scope
;
6186 while Present
(Proc
)
6187 and then Scope
(Proc
) /= Scop
6189 Proc
:= Scope
(Proc
);
6192 Corr
:= Protected_Body_Subprogram
(Proc
);
6196 -- Previous error left expansion incomplete.
6197 -- Nothing to do on this call.
6204 (First
(Parameter_Specifications
(Parent
(Corr
))));
6206 if Is_Subprogram
(Proc
) and then Proc
/= Corr
then
6208 -- Protected function or procedure
6210 Set_Entity
(Rec
, Param
);
6212 -- Rec is a reference to an entity which will not be in scope when
6213 -- the call is reanalyzed, and needs no further analysis.
6218 -- Entry or barrier function for entry body. The first parameter of
6219 -- the entry body procedure is pointer to the object. We create a
6220 -- local variable of the proper type, duplicating what is done to
6221 -- define _object later on.
6225 Obj_Ptr
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
6229 Make_Full_Type_Declaration
(Loc
,
6230 Defining_Identifier
=> Obj_Ptr
,
6232 Make_Access_To_Object_Definition
(Loc
,
6233 Subtype_Indication
=>
6235 (Corresponding_Record_Type
(Scop
), Loc
))));
6237 Insert_Actions
(N
, Decls
);
6238 Freeze_Before
(N
, Obj_Ptr
);
6241 Make_Explicit_Dereference
(Loc
,
6243 Unchecked_Convert_To
(Obj_Ptr
,
6244 New_Occurrence_Of
(Param
, Loc
)));
6246 -- Analyze new actual. Other actuals in calls are already analyzed
6247 -- and the list of actuals is not reanalyzed after rewriting.
6249 Set_Parent
(Rec
, N
);
6255 end Expand_Protected_Object_Reference
;
6257 --------------------------------------
6258 -- Expand_Protected_Subprogram_Call --
6259 --------------------------------------
6261 procedure Expand_Protected_Subprogram_Call
6268 procedure Expand_Internal_Init_Call
;
6269 -- A call to an operation of the type may occur in the initialization
6270 -- of a private component. In that case the prefix of the call is an
6271 -- entity name and the call is treated as internal even though it
6272 -- appears in code outside of the protected type.
6274 procedure Freeze_Called_Function
;
6275 -- If it is a function call it can appear in elaboration code and
6276 -- the called entity must be frozen before the call. This must be
6277 -- done before the call is expanded, as the expansion may rewrite it
6278 -- to something other than a call (e.g. a temporary initialized in a
6279 -- transient block).
6281 -------------------------------
6282 -- Expand_Internal_Init_Call --
6283 -------------------------------
6285 procedure Expand_Internal_Init_Call
is
6287 -- If the context is a protected object (rather than a protected
6288 -- type) the call itself is bound to raise program_error because
6289 -- the protected body will not have been elaborated yet. This is
6290 -- diagnosed subsequently in Sem_Elab.
6292 Freeze_Called_Function
;
6294 -- The target of the internal call is the first formal of the
6295 -- enclosing initialization procedure.
6297 Rec
:= New_Occurrence_Of
(First_Formal
(Current_Scope
), Sloc
(N
));
6298 Build_Protected_Subprogram_Call
(N
,
6303 Resolve
(N
, Etype
(Subp
));
6304 end Expand_Internal_Init_Call
;
6306 ----------------------------
6307 -- Freeze_Called_Function --
6308 ----------------------------
6310 procedure Freeze_Called_Function
is
6312 if Ekind
(Subp
) = E_Function
then
6313 Freeze_Expression
(Name
(N
));
6315 end Freeze_Called_Function
;
6317 -- Start of processing for Expand_Protected_Subprogram_Call
6320 -- If the protected object is not an enclosing scope, this is an inter-
6321 -- object function call. Inter-object procedure calls are expanded by
6322 -- Exp_Ch9.Build_Simple_Entry_Call. The call is intra-object only if the
6323 -- subprogram being called is in the protected body being compiled, and
6324 -- if the protected object in the call is statically the enclosing type.
6325 -- The object may be a component of some other data structure, in which
6326 -- case this must be handled as an inter-object call.
6328 if not Scope_Within_Or_Same
(Inner
=> Current_Scope
, Outer
=> Scop
)
6329 or else Is_Entry_Wrapper
(Current_Scope
)
6330 or else not Is_Entity_Name
(Name
(N
))
6332 if Nkind
(Name
(N
)) = N_Selected_Component
then
6333 Rec
:= Prefix
(Name
(N
));
6335 elsif Nkind
(Name
(N
)) = N_Indexed_Component
then
6336 Rec
:= Prefix
(Prefix
(Name
(N
)));
6338 -- If this is a call within an entry wrapper, it appears within a
6339 -- precondition that calls another primitive of the synchronized
6340 -- type. The target object of the call is the first actual on the
6341 -- wrapper. Note that this is an external call, because the wrapper
6342 -- is called outside of the synchronized object. This means that
6343 -- an entry call to an entry with preconditions involves two
6344 -- synchronized operations.
6346 elsif Ekind
(Current_Scope
) = E_Procedure
6347 and then Is_Entry_Wrapper
(Current_Scope
)
6349 Rec
:= New_Occurrence_Of
(First_Entity
(Current_Scope
), Sloc
(N
));
6351 -- A default parameter of a protected operation may be a call to
6352 -- a protected function of the type. This appears as an internal
6353 -- call in the profile of the operation, but if the context is an
6354 -- external call we must convert the call into an external one,
6355 -- using the protected object that is the target, so that:
6358 -- is transformed into
6361 elsif Nkind
(Parent
(N
)) = N_Procedure_Call_Statement
6362 and then Nkind
(Name
(Parent
(N
))) = N_Selected_Component
6363 and then Is_Protected_Type
(Etype
(Prefix
(Name
(Parent
(N
)))))
6364 and then Is_Entity_Name
(Name
(N
))
6365 and then Scope
(Entity
(Name
(N
))) =
6366 Etype
(Prefix
(Name
(Parent
(N
))))
6369 Make_Selected_Component
(Sloc
(N
),
6370 Prefix
=> New_Copy_Tree
(Prefix
(Name
(Parent
(N
)))),
6371 Selector_Name
=> Relocate_Node
(Name
(N
))));
6373 Analyze_And_Resolve
(N
);
6377 -- If the context is the initialization procedure for a protected
6378 -- type, the call is legal because the called entity must be a
6379 -- function of that enclosing type, and this is treated as an
6383 (Is_Entity_Name
(Name
(N
)) and then Inside_Init_Proc
);
6385 Expand_Internal_Init_Call
;
6389 Freeze_Called_Function
;
6390 Build_Protected_Subprogram_Call
(N
,
6391 Name
=> New_Occurrence_Of
(Subp
, Sloc
(N
)),
6392 Rec
=> Convert_Concurrent
(Rec
, Etype
(Rec
)),
6396 Rec
:= Expand_Protected_Object_Reference
(N
, Scop
);
6402 Freeze_Called_Function
;
6403 Build_Protected_Subprogram_Call
(N
,
6409 -- Analyze and resolve the new call. The actuals have already been
6410 -- resolved, but expansion of a function call will add extra actuals
6411 -- if needed. Analysis of a procedure call already includes resolution.
6415 if Ekind
(Subp
) = E_Function
then
6416 Resolve
(N
, Etype
(Subp
));
6418 end Expand_Protected_Subprogram_Call
;
6420 -----------------------------------
6421 -- Expand_Simple_Function_Return --
6422 -----------------------------------
6424 -- The "simple" comes from the syntax rule simple_return_statement. The
6425 -- semantics are not at all simple.
6427 procedure Expand_Simple_Function_Return
(N
: Node_Id
) is
6428 Loc
: constant Source_Ptr
:= Sloc
(N
);
6430 Scope_Id
: constant Entity_Id
:=
6431 Return_Applies_To
(Return_Statement_Entity
(N
));
6432 -- The function we are returning from
6434 R_Type
: constant Entity_Id
:= Etype
(Scope_Id
);
6435 -- The result type of the function
6437 Utyp
: constant Entity_Id
:= Underlying_Type
(R_Type
);
6438 -- The underlying result type of the function
6440 Exp
: Node_Id
:= Expression
(N
);
6441 pragma Assert
(Present
(Exp
));
6443 Exp_Is_Function_Call
: constant Boolean :=
6444 Nkind
(Exp
) = N_Function_Call
6446 (Is_Captured_Function_Call
(Exp
)
6447 and then Is_Related_To_Func_Return
(Entity
(Prefix
(Exp
))));
6448 -- If the expression is a captured function call, then we need to make
6449 -- sure that the object doing the capture is properly recognized by the
6450 -- Is_Related_To_Func_Return predicate; otherwise, if it is of a type
6451 -- that needs finalization, Requires_Cleanup_Actions would return true
6452 -- because of this and Build_Finalizer would finalize it prematurely.
6454 Exp_Typ
: constant Entity_Id
:= Etype
(Exp
);
6455 -- The type of the expression (not necessarily the same as R_Type)
6457 Subtype_Ind
: Node_Id
;
6458 -- If the result type of the function is class-wide and the expression
6459 -- has a specific type, then we use the expression's type as the type of
6460 -- the return object. In cases where the expression is an aggregate that
6461 -- is built in place, this avoids the need for an expensive conversion
6462 -- of the return object to the specific type on assignments to the
6463 -- individual components.
6465 -- Start of processing for Expand_Simple_Function_Return
6468 if Is_Class_Wide_Type
(R_Type
)
6469 and then not Is_Class_Wide_Type
(Exp_Typ
)
6470 and then Nkind
(Exp
) /= N_Type_Conversion
6472 Subtype_Ind
:= New_Occurrence_Of
(Exp_Typ
, Loc
);
6474 Subtype_Ind
:= New_Occurrence_Of
(R_Type
, Loc
);
6476 -- If the result type is class-wide and the expression is a view
6477 -- conversion, the conversion plays no role in the expansion because
6478 -- it does not modify the tag of the object. Remove the conversion
6479 -- altogether to prevent tag overwriting.
6481 if Is_Class_Wide_Type
(R_Type
)
6482 and then not Is_Class_Wide_Type
(Exp_Typ
)
6483 and then Nkind
(Exp
) = N_Type_Conversion
6485 Exp
:= Expression
(Exp
);
6489 -- Assert that if F says "return G(...);"
6490 -- then F and G are both b-i-p, or neither b-i-p.
6492 if Nkind
(Exp
) = N_Function_Call
then
6493 pragma Assert
(Ekind
(Scope_Id
) = E_Function
);
6495 -- This assertion works fine because Is_Build_In_Place_Function_Call
6496 -- returns True for BIP function calls but also for function calls
6497 -- that have BIP formals.
6500 (Has_BIP_Formals
(Scope_Id
) =
6501 Is_Build_In_Place_Function_Call
(Exp
));
6505 -- For the case of a simple return that does not come from an
6506 -- extended return, in the case of build-in-place, we rewrite
6507 -- "return <expression>;" to be:
6509 -- return _anon_ : <return_subtype> := <expression>
6511 -- The expansion produced by Expand_N_Extended_Return_Statement will
6512 -- contain simple return statements (for example, a block containing
6513 -- simple return of the return object), which brings us back here with
6514 -- Comes_From_Extended_Return_Statement set. The reason for the barrier
6515 -- checking for a simple return that does not come from an extended
6516 -- return is to avoid this infinite recursion.
6518 -- The reason for this design is that for Ada 2005 limited returns, we
6519 -- need to reify the return object, so we can build it "in place", and
6520 -- we need a block statement to hang finalization and tasking stuff.
6523 (Comes_From_Extended_Return_Statement
(N
)
6524 or else not Is_Build_In_Place_Function_Call
(Exp
)
6525 or else Has_BIP_Formals
(Scope_Id
));
6527 if not Comes_From_Extended_Return_Statement
(N
)
6528 and then Is_Build_In_Place_Function
(Scope_Id
)
6530 -- The functionality of interface thunks is simple and it is always
6531 -- handled by means of simple return statements. This leaves their
6532 -- expansion simple and clean.
6534 and then not Is_Thunk
(Scope_Id
)
6537 Return_Object_Entity
: constant Entity_Id
:=
6538 Make_Temporary
(Loc
, 'R', Exp
);
6540 Obj_Decl
: constant Node_Id
:=
6541 Make_Object_Declaration
(Loc
,
6542 Defining_Identifier
=> Return_Object_Entity
,
6543 Object_Definition
=> Subtype_Ind
,
6546 Ext
: constant Node_Id
:=
6547 Make_Extended_Return_Statement
(Loc
,
6548 Return_Object_Declarations
=> New_List
(Obj_Decl
));
6549 -- Do not perform this high-level optimization if the result type
6550 -- is an interface because the "this" pointer must be displaced.
6559 -- Here we have a simple return statement that is part of the expansion
6560 -- of an extended return statement (either written by the user, or
6561 -- generated by the above code).
6563 -- Always normalize C/Fortran boolean result. This is not always needed,
6564 -- but it seems a good idea to minimize the passing around of non-
6565 -- normalized values, and in any case this handles the processing of
6566 -- barrier functions for protected types, which turn the condition into
6567 -- a return statement.
6569 if Is_Boolean_Type
(Exp_Typ
) and then Nonzero_Is_True
(Exp_Typ
) then
6570 Adjust_Condition
(Exp
);
6571 Adjust_Result_Type
(Exp
, Exp_Typ
);
6574 -- Do validity check if enabled for returns
6576 if Validity_Checks_On
and then Validity_Check_Returns
then
6580 -- Check the result expression of a scalar function against the subtype
6581 -- of the function by inserting a conversion. This conversion must
6582 -- eventually be performed for other classes of types, but for now it's
6583 -- only done for scalars ???
6585 if Is_Scalar_Type
(Exp_Typ
) and then Exp_Typ
/= R_Type
then
6586 Rewrite
(Exp
, Convert_To
(R_Type
, Exp
));
6588 -- The expression is resolved to ensure that the conversion gets
6589 -- expanded to generate a possible constraint check.
6591 Analyze_And_Resolve
(Exp
, R_Type
);
6594 -- Deal with returning variable length objects and controlled types
6596 -- Nothing to do if we are returning by reference
6598 if Is_Build_In_Place_Function
(Scope_Id
) then
6599 -- Prevent the reclamation of the secondary stack by all enclosing
6600 -- blocks and loops as well as the related function; otherwise the
6601 -- result would be reclaimed too early.
6603 if Needs_BIP_Alloc_Form
(Scope_Id
) then
6604 Set_Enclosing_Sec_Stack_Return
(N
);
6607 elsif Is_Limited_View
(R_Type
) then
6610 -- No copy needed for thunks returning interface type objects since
6611 -- the object is returned by reference and the maximum functionality
6612 -- required is just to displace the pointer.
6614 elsif Is_Thunk
(Scope_Id
) and then Is_Interface
(Exp_Typ
) then
6617 -- If the call is within a thunk and the type is a limited view, the
6618 -- back end will eventually see the non-limited view of the type.
6620 elsif Is_Thunk
(Scope_Id
) and then Is_Incomplete_Type
(Exp_Typ
) then
6623 -- A return statement from an ignored Ghost function does not use the
6624 -- secondary stack (or any other one).
6626 elsif (not Needs_Secondary_Stack
(R_Type
)
6627 and then not Is_Secondary_Stack_Thunk
(Scope_Id
))
6628 or else Is_Ignored_Ghost_Entity
(Scope_Id
)
6630 -- Mutable records with variable-length components are not returned
6631 -- on the sec-stack, so we need to make sure that the back end will
6632 -- only copy back the size of the actual value, and not the maximum
6633 -- size. We create an actual subtype for this purpose. However we
6634 -- need not do it if the expression is a function call since this
6635 -- will be done in the called function and doing it here too would
6636 -- cause a temporary with maximum size to be created. Likewise for
6637 -- a special return object, since there is no copy in this case.
6640 Ubt
: constant Entity_Id
:= Underlying_Type
(Base_Type
(Exp_Typ
));
6645 if not Exp_Is_Function_Call
6646 and then not (Is_Entity_Name
(Exp
)
6647 and then Is_Special_Return_Object
(Entity
(Exp
)))
6648 and then Has_Defaulted_Discriminants
(Ubt
)
6649 and then not Is_Constrained
(Ubt
)
6650 and then not Has_Unchecked_Union
(Ubt
)
6652 Decl
:= Build_Actual_Subtype
(Ubt
, Exp
);
6653 Ent
:= Defining_Identifier
(Decl
);
6654 Insert_Action
(Exp
, Decl
);
6655 Rewrite
(Exp
, Unchecked_Convert_To
(Ent
, Exp
));
6656 Analyze_And_Resolve
(Exp
);
6660 -- For types which need finalization, do the allocation on the return
6661 -- stack manually in order to call Adjust at the right time:
6663 -- type Ann is access R_Type;
6664 -- for Ann'Storage_pool use rs_pool;
6665 -- Rnn : constant Ann := new Exp_Typ'(Exp);
6668 -- but optimize the case where the result is a function call that
6669 -- also needs finalization. In this case the result can directly be
6670 -- allocated on the return stack of the caller and no further
6671 -- processing is required. Likewise if this is a return object.
6673 if Comes_From_Extended_Return_Statement
(N
) then
6676 elsif Present
(Utyp
)
6677 and then Needs_Finalization
(Utyp
)
6678 and then not (Exp_Is_Function_Call
6679 and then Needs_Finalization
(Exp_Typ
))
6682 Acc_Typ
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
6684 Alloc_Node
: Node_Id
;
6688 Mutate_Ekind
(Acc_Typ
, E_Access_Type
);
6690 Set_Associated_Storage_Pool
(Acc_Typ
, RTE
(RE_RS_Pool
));
6692 -- This is an allocator for the return stack, and it's fine
6693 -- to have Comes_From_Source set False on it, as gigi knows not
6694 -- to flag it as a violation of No_Implicit_Heap_Allocations.
6697 Make_Allocator
(Loc
,
6699 Make_Qualified_Expression
(Loc
,
6700 Subtype_Mark
=> New_Occurrence_Of
(Exp_Typ
, Loc
),
6701 Expression
=> Relocate_Node
(Exp
)));
6703 -- We do not want discriminant checks on the declaration,
6704 -- given that it gets its value from the allocator.
6706 Set_No_Initialization
(Alloc_Node
);
6708 Temp
:= Make_Temporary
(Loc
, 'R', Alloc_Node
);
6710 Insert_Actions
(Exp
, New_List
(
6711 Make_Full_Type_Declaration
(Loc
,
6712 Defining_Identifier
=> Acc_Typ
,
6714 Make_Access_To_Object_Definition
(Loc
,
6715 Subtype_Indication
=> Subtype_Ind
)),
6717 Make_Object_Declaration
(Loc
,
6718 Defining_Identifier
=> Temp
,
6719 Constant_Present
=> True,
6720 Object_Definition
=> New_Occurrence_Of
(Acc_Typ
, Loc
),
6721 Expression
=> Alloc_Node
)));
6724 Make_Explicit_Dereference
(Loc
,
6725 Prefix
=> New_Occurrence_Of
(Temp
, Loc
)));
6727 Analyze_And_Resolve
(Exp
, R_Type
);
6731 -- Here if secondary stack is used
6734 -- Prevent the reclamation of the secondary stack by all enclosing
6735 -- blocks and loops as well as the related function; otherwise the
6736 -- result would be reclaimed too early.
6738 Set_Enclosing_Sec_Stack_Return
(N
);
6740 -- Nothing else to do for a return object
6742 if Comes_From_Extended_Return_Statement
(N
) then
6745 -- Optimize the case where the result is a function call that also
6746 -- returns on the secondary stack. In this case the result is already
6747 -- on the secondary stack and no further processing is required.
6749 elsif Exp_Is_Function_Call
6750 and then Needs_Secondary_Stack
(Exp_Typ
)
6752 -- Remove side effects from the expression now so that other parts
6753 -- of the expander do not have to reanalyze this node without this
6756 Rewrite
(Exp
, Duplicate_Subexpr_No_Checks
(Exp
));
6758 -- Ada 2005 (AI-251): If the type of the returned object is
6759 -- an interface then add an implicit type conversion to force
6760 -- displacement of the "this" pointer.
6762 if Is_Interface
(R_Type
) then
6763 Rewrite
(Exp
, Convert_To
(R_Type
, Relocate_Node
(Exp
)));
6766 Analyze_And_Resolve
(Exp
, R_Type
);
6768 -- For types which both need finalization and are returned on the
6769 -- secondary stack, do the allocation on secondary stack manually
6770 -- in order to call Adjust at the right time:
6772 -- type Ann is access R_Type;
6773 -- for Ann'Storage_pool use ss_pool;
6774 -- Rnn : constant Ann := new Exp_Typ'(Exp);
6777 -- And we do the same for class-wide types that are not potentially
6778 -- controlled (by the virtue of restriction No_Finalization) because
6779 -- gigi is not able to properly allocate class-wide types.
6781 -- But optimize the case where the result is a function call that
6782 -- also needs finalization. In this case the result can directly be
6783 -- allocated on the secondary stack and no further processing is
6786 elsif CW_Or_Needs_Finalization
(Utyp
)
6787 and then not (Exp_Is_Function_Call
6788 and then Needs_Finalization
(Exp_Typ
))
6791 Acc_Typ
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
6793 Alloc_Node
: Node_Id
;
6797 Mutate_Ekind
(Acc_Typ
, E_Access_Type
);
6798 Set_Associated_Storage_Pool
(Acc_Typ
, RTE
(RE_SS_Pool
));
6800 -- This is an allocator for the secondary stack, and it's fine
6801 -- to have Comes_From_Source set False on it, as gigi knows not
6802 -- to flag it as a violation of No_Implicit_Heap_Allocations.
6805 Make_Allocator
(Loc
,
6807 Make_Qualified_Expression
(Loc
,
6808 Subtype_Mark
=> New_Occurrence_Of
(Etype
(Exp
), Loc
),
6809 Expression
=> Relocate_Node
(Exp
)));
6811 -- We do not want discriminant checks on the declaration,
6812 -- given that it gets its value from the allocator.
6814 Set_No_Initialization
(Alloc_Node
);
6816 Temp
:= Make_Temporary
(Loc
, 'R', Alloc_Node
);
6818 Insert_List_Before_And_Analyze
(N
, New_List
(
6819 Make_Full_Type_Declaration
(Loc
,
6820 Defining_Identifier
=> Acc_Typ
,
6822 Make_Access_To_Object_Definition
(Loc
,
6823 Subtype_Indication
=> Subtype_Ind
)),
6825 Make_Object_Declaration
(Loc
,
6826 Defining_Identifier
=> Temp
,
6827 Constant_Present
=> True,
6828 Object_Definition
=> New_Occurrence_Of
(Acc_Typ
, Loc
),
6829 Expression
=> Alloc_Node
)));
6832 Make_Explicit_Dereference
(Loc
,
6833 Prefix
=> New_Occurrence_Of
(Temp
, Loc
)));
6835 -- Ada 2005 (AI-251): If the type of the returned object is
6836 -- an interface then add an implicit type conversion to force
6837 -- displacement of the "this" pointer.
6839 if Is_Interface
(R_Type
) then
6840 Rewrite
(Exp
, Convert_To
(R_Type
, Relocate_Node
(Exp
)));
6843 Analyze_And_Resolve
(Exp
, R_Type
);
6846 -- Otherwise use the gigi mechanism to allocate result on the
6850 Check_Restriction
(No_Secondary_Stack
, N
);
6851 Set_Storage_Pool
(N
, RTE
(RE_SS_Pool
));
6852 Set_Procedure_To_Call
(N
, RTE
(RE_SS_Allocate
));
6856 -- Implement the rules of 6.5(8-10), which require a tag check in
6857 -- the case of a limited tagged return type, and tag reassignment for
6858 -- nonlimited tagged results. These actions are needed when the return
6859 -- type is a specific tagged type and the result expression is a
6860 -- conversion or a formal parameter, because in that case the tag of
6861 -- the expression might differ from the tag of the specific result type.
6863 -- We must also verify an underlying type exists for the return type in
6864 -- case it is incomplete - in which case is not necessary to generate a
6865 -- check anyway since an incomplete limited tagged return type would
6866 -- qualify as a premature usage.
6869 and then Is_Tagged_Type
(Utyp
)
6870 and then not Is_Class_Wide_Type
(Utyp
)
6871 and then (Nkind
(Exp
) in
6872 N_Type_Conversion | N_Unchecked_Type_Conversion
6873 or else (Nkind
(Exp
) = N_Explicit_Dereference
6874 and then Nkind
(Prefix
(Exp
)) in
6876 N_Unchecked_Type_Conversion
)
6877 or else (Is_Entity_Name
(Exp
)
6878 and then Is_Formal
(Entity
(Exp
))))
6880 -- When the return type is limited, perform a check that the tag of
6881 -- the result is the same as the tag of the return type.
6883 if Is_Limited_Type
(R_Type
) then
6885 Make_Raise_Constraint_Error
(Loc
,
6889 Make_Selected_Component
(Loc
,
6890 Prefix
=> Duplicate_Subexpr
(Exp
),
6891 Selector_Name
=> Make_Identifier
(Loc
, Name_uTag
)),
6893 Make_Attribute_Reference
(Loc
,
6895 New_Occurrence_Of
(Base_Type
(Utyp
), Loc
),
6896 Attribute_Name
=> Name_Tag
)),
6897 Reason
=> CE_Tag_Check_Failed
));
6899 -- If the result type is a specific nonlimited tagged type, then we
6900 -- have to ensure that the tag of the result is that of the result
6901 -- type. This is handled by making a copy of the expression in
6902 -- the case where it might have a different tag, namely when the
6903 -- expression is a conversion or a formal parameter. We create a new
6904 -- object of the result type and initialize it from the expression,
6905 -- which will implicitly force the tag to be set appropriately.
6909 ExpR
: constant Node_Id
:= Relocate_Node
(Exp
);
6910 Result_Id
: constant Entity_Id
:=
6911 Make_Temporary
(Loc
, 'R', ExpR
);
6912 Result_Exp
: constant Node_Id
:=
6913 New_Occurrence_Of
(Result_Id
, Loc
);
6914 Result_Obj
: constant Node_Id
:=
6915 Make_Object_Declaration
(Loc
,
6916 Defining_Identifier
=> Result_Id
,
6917 Object_Definition
=>
6918 New_Occurrence_Of
(R_Type
, Loc
),
6919 Constant_Present
=> True,
6920 Expression
=> ExpR
);
6923 Set_Assignment_OK
(Result_Obj
);
6924 Insert_Action
(Exp
, Result_Obj
);
6926 Rewrite
(Exp
, Result_Exp
);
6927 Analyze_And_Resolve
(Exp
, R_Type
);
6931 -- Ada 2005 (AI95-344): If the result type is class-wide, then insert
6932 -- a check that the level of the return expression's underlying type
6933 -- is not deeper than the level of the master enclosing the function.
6935 -- AI12-043: The check is made immediately after the return object is
6936 -- created. This means that we do not apply it to the simple return
6937 -- generated by the expansion of an extended return statement.
6939 -- No runtime check needed in interface thunks since it is performed
6940 -- by the target primitive associated with the thunk.
6942 elsif Is_Class_Wide_Type
(R_Type
)
6943 and then not Comes_From_Extended_Return_Statement
(N
)
6944 and then not Is_Thunk
(Scope_Id
)
6946 Apply_CW_Accessibility_Check
(Exp
, Scope_Id
);
6948 -- Ada 2012 (AI05-0073): If the result subtype of the function is
6949 -- defined by an access_definition designating a specific tagged
6950 -- type T, a check is made that the result value is null or the tag
6951 -- of the object designated by the result value identifies T.
6953 -- The return expression is referenced twice in the code below, so it
6954 -- must be made free of side effects. Given that different compilers
6955 -- may evaluate these parameters in different order, both occurrences
6958 elsif Ekind
(R_Type
) = E_Anonymous_Access_Type
6959 and then Is_Tagged_Type
(Designated_Type
(R_Type
))
6960 and then not Is_Class_Wide_Type
(Designated_Type
(R_Type
))
6961 and then Nkind
(Original_Node
(Exp
)) /= N_Null
6962 and then not Tag_Checks_Suppressed
(Designated_Type
(R_Type
))
6965 -- [Constraint_Error
6967 -- and then Exp.all not in Designated_Type]
6970 Make_Raise_Constraint_Error
(Loc
,
6975 Left_Opnd
=> Duplicate_Subexpr
(Exp
),
6976 Right_Opnd
=> Make_Null
(Loc
)),
6981 Make_Explicit_Dereference
(Loc
,
6982 Prefix
=> Duplicate_Subexpr
(Exp
)),
6984 New_Occurrence_Of
(Designated_Type
(R_Type
), Loc
))),
6986 Reason
=> CE_Tag_Check_Failed
),
6987 Suppress
=> All_Checks
);
6990 -- If the result is of an unconstrained array subtype with fixed lower
6991 -- bound, then sliding to that bound may be needed.
6993 if Is_Fixed_Lower_Bound_Array_Subtype
(R_Type
) then
6994 Expand_Sliding_Conversion
(Exp
, R_Type
);
6997 -- If we are returning a nonscalar object that is possibly unaligned,
6998 -- then copy the value into a temporary first. This copy may need to
6999 -- expand to a loop of component operations.
7001 if Is_Possibly_Unaligned_Slice
(Exp
)
7002 or else (Is_Possibly_Unaligned_Object
(Exp
)
7003 and then not Represented_As_Scalar
(Etype
(Exp
)))
7006 ExpR
: constant Node_Id
:= Relocate_Node
(Exp
);
7007 Tnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', ExpR
);
7010 Make_Object_Declaration
(Loc
,
7011 Defining_Identifier
=> Tnn
,
7012 Constant_Present
=> True,
7013 Object_Definition
=> New_Occurrence_Of
(R_Type
, Loc
),
7014 Expression
=> ExpR
),
7015 Suppress
=> All_Checks
);
7016 Rewrite
(Exp
, New_Occurrence_Of
(Tnn
, Loc
));
7020 -- Ada 2005 (AI-251): If this return statement corresponds with an
7021 -- simple return statement associated with an extended return statement
7022 -- and the type of the returned object is an interface then generate an
7023 -- implicit conversion to force displacement of the "this" pointer.
7025 if Ada_Version
>= Ada_2005
7026 and then Comes_From_Extended_Return_Statement
(N
)
7027 and then Nkind
(Expression
(N
)) = N_Identifier
7028 and then Is_Interface
(Utyp
)
7029 and then Utyp
/= Underlying_Type
(Exp_Typ
)
7031 Rewrite
(Exp
, Convert_To
(Utyp
, Relocate_Node
(Exp
)));
7032 Analyze_And_Resolve
(Exp
);
7035 -- Ada 2022 (AI12-0279)
7037 if Has_Yield_Aspect
(Scope_Id
)
7038 and then RTE_Available
(RE_Yield
)
7041 Make_Procedure_Call_Statement
(Loc
,
7042 New_Occurrence_Of
(RTE
(RE_Yield
), Loc
)));
7044 end Expand_Simple_Function_Return
;
7046 -----------------------
7047 -- Freeze_Subprogram --
7048 -----------------------
7050 procedure Freeze_Subprogram
(N
: Node_Id
) is
7051 Loc
: constant Source_Ptr
:= Sloc
(N
);
7052 Subp
: constant Entity_Id
:= Entity
(N
);
7055 -- We suppress the initialization of the dispatch table entry when
7056 -- not Tagged_Type_Expansion because the dispatching mechanism is
7057 -- handled internally by the target.
7059 if Is_Dispatching_Operation
(Subp
)
7060 and then not Is_Abstract_Subprogram
(Subp
)
7061 and then Present
(DTC_Entity
(Subp
))
7062 and then Present
(Scope
(DTC_Entity
(Subp
)))
7063 and then Tagged_Type_Expansion
7064 and then not Restriction_Active
(No_Dispatching_Calls
)
7065 and then RTE_Available
(RE_Tag
)
7068 Typ
: constant Entity_Id
:= Scope
(DTC_Entity
(Subp
));
7073 -- Handle private overridden primitives
7075 if not Is_CPP_Class
(Typ
) then
7076 Check_Overriding_Operation
(Subp
);
7079 -- We assume that imported CPP primitives correspond with objects
7080 -- whose constructor is in the CPP side; therefore we don't need
7081 -- to generate code to register them in the dispatch table.
7083 if Is_CPP_Class
(Typ
) then
7086 -- Handle CPP primitives found in derivations of CPP_Class types.
7087 -- These primitives must have been inherited from some parent, and
7088 -- there is no need to register them in the dispatch table because
7089 -- Build_Inherit_Prims takes care of initializing these slots.
7091 elsif Is_Imported
(Subp
)
7092 and then Convention
(Subp
) in Convention_C_Family
7096 -- Generate code to register the primitive in non statically
7097 -- allocated dispatch tables
7099 elsif not Building_Static_DT
(Scope
(DTC_Entity
(Subp
))) then
7101 -- When a primitive is frozen, enter its name in its dispatch
7104 if not Is_Interface
(Typ
)
7105 or else Present
(Interface_Alias
(Subp
))
7107 if Is_Predefined_Dispatching_Operation
(Subp
) then
7108 L
:= Register_Predefined_Primitive
(Loc
, Subp
);
7113 Append_List_To
(L
, Register_Primitive
(Loc
, Subp
));
7115 if Is_Empty_List
(L
) then
7118 elsif No
(Actions
(N
)) then
7122 Append_List
(L
, Actions
(N
));
7129 -- Mark functions that return by reference. Note that it cannot be part
7130 -- of the normal semantic analysis of the spec since the underlying
7131 -- returned type may not be known yet (for private types).
7133 Compute_Returns_By_Ref
(Subp
);
7134 end Freeze_Subprogram
;
7136 --------------------------
7137 -- Has_BIP_Extra_Formal --
7138 --------------------------
7140 function Has_BIP_Extra_Formal
7142 Kind
: BIP_Formal_Kind
;
7143 Must_Be_Frozen
: Boolean := True) return Boolean
7145 Extra_Formal
: Entity_Id
:= Extra_Formals
(E
);
7148 -- We can only rely on the availability of the extra formals in frozen
7149 -- entities or in subprogram types of dispatching calls (since their
7150 -- extra formals are added when the target subprogram is frozen; see
7151 -- Expand_Dispatching_Call).
7153 pragma Assert
((Is_Frozen
(E
) or else not Must_Be_Frozen
)
7154 or else (Ekind
(E
) = E_Subprogram_Type
7155 and then Is_Dispatch_Table_Entity
(E
))
7156 or else (Is_Dispatching_Operation
(E
)
7157 and then Is_Frozen
(Find_Dispatching_Type
(E
))));
7159 while Present
(Extra_Formal
) loop
7160 if Is_Build_In_Place_Entity
(Extra_Formal
)
7161 and then BIP_Suffix_Kind
(Extra_Formal
) = Kind
7166 Next_Formal_With_Extras
(Extra_Formal
);
7170 end Has_BIP_Extra_Formal
;
7172 ------------------------------
7173 -- Insert_Post_Call_Actions --
7174 ------------------------------
7176 procedure Insert_Post_Call_Actions
(N
: Node_Id
; Post_Call
: List_Id
) is
7177 Context
: constant Node_Id
:= Parent
(N
);
7180 if Is_Empty_List
(Post_Call
) then
7184 -- Cases where the call is not a member of a statement list. This also
7185 -- includes the cases where the call is an actual in another function
7186 -- call, or is an index, or is an operand of an if-expression, i.e. is
7187 -- in an expression context.
7189 if not Is_List_Member
(N
)
7190 or else Nkind
(Context
) in N_Function_Call
7192 | N_Indexed_Component
7194 -- In Ada 2012 the call may be a function call in an expression
7195 -- (since OUT and IN OUT parameters are now allowed for such calls).
7196 -- The write-back of (in)-out parameters is handled by the back-end,
7197 -- but the constraint checks generated when subtypes of formal and
7198 -- actual don't match must be inserted in the form of assignments.
7199 -- Also do this in the case of explicit dereferences, which can occur
7200 -- due to rewritings of function calls with controlled results.
7202 if Nkind
(N
) = N_Function_Call
7203 or else Nkind
(Original_Node
(N
)) = N_Function_Call
7204 or else Nkind
(N
) = N_Explicit_Dereference
7206 pragma Assert
(Ada_Version
>= Ada_2012
);
7207 -- Functions with '[in] out' parameters are only allowed in Ada
7210 -- We used to handle this by climbing up parents to a
7211 -- non-statement/declaration and then simply making a call to
7212 -- Insert_Actions_After (P, Post_Call), but that doesn't work
7213 -- for Ada 2012. If we are in the middle of an expression, e.g.
7214 -- the condition of an IF, this call would insert after the IF
7215 -- statement, which is much too late to be doing the write back.
7218 -- if Clobber (X) then
7219 -- Put_Line (X'Img);
7224 -- Now assume Clobber changes X, if we put the write back after
7225 -- the IF, the Put_Line gets the wrong value and the goto causes
7226 -- the write back to be skipped completely.
7228 -- To deal with this, we replace the call by
7231 -- Tnnn : constant function-result-type := function-call;
7232 -- Post_Call actions
7237 -- However, that doesn't work if function-result-type requires
7238 -- finalization (because function-call's result never gets
7239 -- finalized). So in that case, we instead replace the call by
7242 -- type Ref is access all function-result-type;
7243 -- Ptr : constant Ref := function-call'Reference;
7244 -- Tnnn : constant function-result-type := Ptr.all;
7245 -- Finalize (Ptr.all);
7246 -- Post_Call actions
7253 Loc
: constant Source_Ptr
:= Sloc
(N
);
7254 Tnnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
7255 FRTyp
: constant Entity_Id
:= Etype
(N
);
7256 Name
: constant Node_Id
:= Relocate_Node
(N
);
7259 if Needs_Finalization
(FRTyp
) then
7261 Ptr_Typ
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
7263 Ptr_Typ_Decl
: constant Node_Id
:=
7264 Make_Full_Type_Declaration
(Loc
,
7265 Defining_Identifier
=> Ptr_Typ
,
7267 Make_Access_To_Object_Definition
(Loc
,
7268 All_Present
=> True,
7269 Subtype_Indication
=>
7270 New_Occurrence_Of
(FRTyp
, Loc
)));
7272 Ptr_Obj
: constant Entity_Id
:=
7273 Make_Temporary
(Loc
, 'P');
7275 Ptr_Obj_Decl
: constant Node_Id
:=
7276 Make_Object_Declaration
(Loc
,
7277 Defining_Identifier
=> Ptr_Obj
,
7278 Object_Definition
=>
7279 New_Occurrence_Of
(Ptr_Typ
, Loc
),
7280 Constant_Present
=> True,
7282 Make_Attribute_Reference
(Loc
,
7284 Attribute_Name
=> Name_Unrestricted_Access
));
7286 function Ptr_Dereference
return Node_Id
is
7287 (Make_Explicit_Dereference
(Loc
,
7288 Prefix
=> New_Occurrence_Of
(Ptr_Obj
, Loc
)));
7290 Tnn_Decl
: constant Node_Id
:=
7291 Make_Object_Declaration
(Loc
,
7292 Defining_Identifier
=> Tnnn
,
7293 Object_Definition
=> New_Occurrence_Of
(FRTyp
, Loc
),
7294 Constant_Present
=> True,
7295 Expression
=> Ptr_Dereference
);
7297 Finalize_Call
: constant Node_Id
:=
7299 (Obj_Ref
=> Ptr_Dereference
, Typ
=> FRTyp
);
7301 -- Prepend in reverse order
7303 Prepend_To
(Post_Call
, Finalize_Call
);
7304 Prepend_To
(Post_Call
, Tnn_Decl
);
7305 Prepend_To
(Post_Call
, Ptr_Obj_Decl
);
7306 Prepend_To
(Post_Call
, Ptr_Typ_Decl
);
7309 Prepend_To
(Post_Call
,
7310 Make_Object_Declaration
(Loc
,
7311 Defining_Identifier
=> Tnnn
,
7312 Object_Definition
=> New_Occurrence_Of
(FRTyp
, Loc
),
7313 Constant_Present
=> True,
7314 Expression
=> Name
));
7318 Make_Expression_With_Actions
(Loc
,
7319 Actions
=> Post_Call
,
7320 Expression
=> New_Occurrence_Of
(Tnnn
, Loc
)));
7322 -- We don't want to just blindly call Analyze_And_Resolve
7323 -- because that would cause unwanted recursion on the call.
7324 -- So for a moment set the call as analyzed to prevent that
7325 -- recursion, and get the rest analyzed properly, then reset
7326 -- the analyzed flag, so our caller can continue.
7328 Set_Analyzed
(Name
, True);
7329 Analyze_And_Resolve
(N
, FRTyp
);
7330 Set_Analyzed
(Name
, False);
7333 -- If not the special Ada 2012 case of a function call, then we must
7334 -- have the triggering statement of a triggering alternative or an
7335 -- entry call alternative, and we can add the post call stuff to the
7336 -- corresponding statement list.
7339 pragma Assert
(Nkind
(Context
) in N_Entry_Call_Alternative
7340 | N_Triggering_Alternative
);
7342 if Is_Non_Empty_List
(Statements
(Context
)) then
7343 Insert_List_Before_And_Analyze
7344 (First
(Statements
(Context
)), Post_Call
);
7346 Set_Statements
(Context
, Post_Call
);
7350 -- A procedure call is always part of a declarative or statement list,
7351 -- however a function call may appear nested within a construct. Most
7352 -- cases of function call nesting are handled in the special case above.
7353 -- The only exception is when the function call acts as an actual in a
7354 -- procedure call. In this case the function call is in a list, but the
7355 -- post-call actions must be inserted after the procedure call.
7356 -- What if the function call is an aggregate component ???
7358 elsif Nkind
(Context
) = N_Procedure_Call_Statement
then
7359 Insert_Actions_After
(Context
, Post_Call
);
7361 -- Otherwise, normal case where N is in a statement sequence, just put
7362 -- the post-call stuff after the call statement.
7365 Insert_Actions_After
(N
, Post_Call
);
7367 end Insert_Post_Call_Actions
;
7369 ---------------------------------------
7370 -- Install_Class_Preconditions_Check --
7371 ---------------------------------------
7373 procedure Install_Class_Preconditions_Check
(Call_Node
: Node_Id
) is
7374 Loc
: constant Source_Ptr
:= Sloc
(Call_Node
);
7376 function Build_Dynamic_Check_Helper_Call
return Node_Id
;
7377 -- Build call to the helper runtime function of the nearest ancestor
7378 -- of the target subprogram that dynamically evaluates the merged
7379 -- or-else preconditions.
7381 function Build_Error_Message
(Subp_Id
: Entity_Id
) return Node_Id
;
7382 -- Build message associated with the class-wide precondition of Subp_Id
7383 -- indicating the call that caused it.
7385 function Build_Static_Check_Helper_Call
return Node_Id
;
7386 -- Build call to the helper runtime function of the nearest ancestor
7387 -- of the target subprogram that dynamically evaluates the merged
7388 -- or-else preconditions.
7390 function Class_Preconditions_Subprogram
7391 (Spec_Id
: Entity_Id
;
7392 Dynamic
: Boolean) return Node_Id
;
7393 -- Return the nearest ancestor of Spec_Id defining a helper function
7394 -- that evaluates a combined or-else expression containing all the
7395 -- inherited class-wide preconditions; Dynamic enables searching for
7396 -- the helper that dynamically evaluates preconditions using dispatching
7397 -- calls; if False it searches for the helper that statically evaluates
7398 -- preconditions; return Empty when not available (which means that no
7399 -- preconditions check is required).
7401 -------------------------------------
7402 -- Build_Dynamic_Check_Helper_Call --
7403 -------------------------------------
7405 function Build_Dynamic_Check_Helper_Call
return Node_Id
is
7406 Spec_Id
: constant Entity_Id
:= Entity
(Name
(Call_Node
));
7407 CW_Subp
: constant Entity_Id
:=
7408 Class_Preconditions_Subprogram
(Spec_Id
,
7410 Helper_Id
: constant Entity_Id
:=
7411 Dynamic_Call_Helper
(CW_Subp
);
7412 Actuals
: constant List_Id
:= New_List
;
7413 A
: Node_Id
:= First_Actual
(Call_Node
);
7414 F
: Entity_Id
:= First_Formal
(Helper_Id
);
7417 while Present
(A
) loop
7419 -- Ensure that the evaluation of the actuals will not produce
7422 Remove_Side_Effects
(A
);
7424 Append_To
(Actuals
, New_Copy_Tree
(A
));
7430 Make_Function_Call
(Loc
,
7431 Name
=> New_Occurrence_Of
(Helper_Id
, Loc
),
7432 Parameter_Associations
=> Actuals
);
7433 end Build_Dynamic_Check_Helper_Call
;
7435 -------------------------
7436 -- Build_Error_Message --
7437 -------------------------
7439 function Build_Error_Message
(Subp_Id
: Entity_Id
) return Node_Id
is
7441 procedure Append_Message
7443 Is_First
: in out Boolean);
7444 -- Build the fragment of the message associated with subprogram Id;
7445 -- Is_First facilitates identifying continuation messages.
7447 --------------------
7448 -- Append_Message --
7449 --------------------
7451 procedure Append_Message
7453 Is_First
: in out Boolean)
7455 Prag
: constant Node_Id
:= Get_Class_Wide_Pragma
(Id
,
7456 Pragma_Precondition
);
7461 if No
(Prag
) or else Is_Ignored
(Prag
) then
7465 Msg
:= Expression
(Last
(Pragma_Argument_Associations
(Prag
)));
7466 Str_Id
:= Strval
(Msg
);
7471 Append
(Global_Name_Buffer
, Strval
(Msg
));
7474 and then Name_Buffer
(1 .. 19) = "failed precondition"
7476 Insert_Str_In_Name_Buffer
("inherited ", 8);
7481 Str
: constant String := To_String
(Str_Id
);
7485 Append
(Global_Name_Buffer
, ASCII
.LF
);
7486 Append
(Global_Name_Buffer
, " or ");
7488 From_Idx
:= Name_Len
;
7489 Append
(Global_Name_Buffer
, Str_Id
);
7491 if Str
(1 .. 19) = "failed precondition" then
7492 Insert_Str_In_Name_Buffer
("inherited ", From_Idx
+ 8);
7500 Str_Loc
: constant String := Build_Location_String
(Loc
);
7501 Subps
: constant Subprogram_List
:=
7502 Inherited_Subprograms
(Subp_Id
);
7503 Is_First
: Boolean := True;
7505 -- Start of processing for Build_Error_Message
7509 Append_Message
(Subp_Id
, Is_First
);
7511 for Index
in Subps
'Range loop
7512 Append_Message
(Subps
(Index
), Is_First
);
7515 if Present
(Controlling_Argument
(Call_Node
)) then
7516 Append
(Global_Name_Buffer
, " in dispatching call at ");
7518 Append
(Global_Name_Buffer
, " in call at ");
7521 Append
(Global_Name_Buffer
, Str_Loc
);
7523 return Make_String_Literal
(Loc
, Name_Buffer
(1 .. Name_Len
));
7524 end Build_Error_Message
;
7526 ------------------------------------
7527 -- Build_Static_Check_Helper_Call --
7528 ------------------------------------
7530 function Build_Static_Check_Helper_Call
return Node_Id
is
7531 Actuals
: constant List_Id
:= New_List
;
7533 Helper_Id
: Entity_Id
;
7535 CW_Subp
: Entity_Id
;
7536 Spec_Id
: constant Entity_Id
:= Entity
(Name
(Call_Node
));
7539 -- The target is the wrapper built to support inheriting body but
7540 -- overriding pre/postconditions (AI12-0195).
7542 if Is_Dispatch_Table_Wrapper
(Spec_Id
) then
7548 CW_Subp
:= Class_Preconditions_Subprogram
(Spec_Id
,
7552 Helper_Id
:= Static_Call_Helper
(CW_Subp
);
7554 F
:= First_Formal
(Helper_Id
);
7555 A
:= First_Actual
(Call_Node
);
7556 while Present
(A
) loop
7558 -- Ensure that the evaluation of the actuals will not produce
7561 Remove_Side_Effects
(A
);
7563 -- Ensure matching types to avoid reporting spurious errors since
7564 -- the called helper may have been built for a parent type.
7566 if Etype
(F
) /= Etype
(A
) then
7568 Unchecked_Convert_To
(Etype
(F
), New_Copy_Tree
(A
)));
7570 Append_To
(Actuals
, New_Copy_Tree
(A
));
7578 Make_Function_Call
(Loc
,
7579 Name
=> New_Occurrence_Of
(Helper_Id
, Loc
),
7580 Parameter_Associations
=> Actuals
);
7581 end Build_Static_Check_Helper_Call
;
7583 ------------------------------------
7584 -- Class_Preconditions_Subprogram --
7585 ------------------------------------
7587 function Class_Preconditions_Subprogram
7588 (Spec_Id
: Entity_Id
;
7589 Dynamic
: Boolean) return Node_Id
7591 Subp_Id
: constant Entity_Id
:= Ultimate_Alias
(Spec_Id
);
7594 -- Prevent cascaded errors
7596 if not Is_Dispatching_Operation
(Subp_Id
) then
7599 -- No need to search if this subprogram has the helper we are
7603 if Present
(Dynamic_Call_Helper
(Subp_Id
)) then
7607 if Present
(Static_Call_Helper
(Subp_Id
)) then
7612 -- Process inherited subprograms looking for class-wide
7616 Subps
: constant Subprogram_List
:=
7617 Inherited_Subprograms
(Subp_Id
);
7618 Subp_Id
: Entity_Id
;
7621 for Index
in Subps
'Range loop
7622 Subp_Id
:= Subps
(Index
);
7624 if Present
(Alias
(Subp_Id
)) then
7625 Subp_Id
:= Ultimate_Alias
(Subp_Id
);
7628 -- Wrappers of class-wide pre/postconditions reference the
7629 -- parent primitive that has the inherited contract.
7631 if Is_Wrapper
(Subp_Id
)
7632 and then Present
(LSP_Subprogram
(Subp_Id
))
7634 Subp_Id
:= LSP_Subprogram
(Subp_Id
);
7638 if Present
(Dynamic_Call_Helper
(Subp_Id
)) then
7642 if Present
(Static_Call_Helper
(Subp_Id
)) then
7650 end Class_Preconditions_Subprogram
;
7654 Dynamic_Check
: constant Boolean :=
7655 Present
(Controlling_Argument
(Call_Node
));
7656 Class_Subp
: Entity_Id
;
7660 -- Start of processing for Install_Class_Preconditions_Check
7663 -- Do not expand the check if we are compiling under restriction
7664 -- No_Dispatching_Calls; the semantic analyzer has previously
7665 -- notified the violation of this restriction.
7668 and then Restriction_Active
(No_Dispatching_Calls
)
7672 -- Class-wide precondition check not needed in interface thunks since
7673 -- they are installed in the dispatching call that caused invoking the
7676 elsif Is_Thunk
(Current_Scope
) then
7680 Subp
:= Entity
(Name
(Call_Node
));
7682 -- No check needed for this subprogram call if no class-wide
7683 -- preconditions apply (or if the unique available preconditions
7684 -- are ignored preconditions).
7686 Class_Subp
:= Class_Preconditions_Subprogram
(Subp
, Dynamic_Check
);
7689 or else No
(Class_Preconditions
(Class_Subp
))
7694 -- Build and install the check
7696 if Dynamic_Check
then
7697 Cond
:= Build_Dynamic_Check_Helper_Call
;
7699 Cond
:= Build_Static_Check_Helper_Call
;
7702 if Exception_Locations_Suppressed
then
7703 Insert_Action
(Call_Node
,
7704 Make_If_Statement
(Loc
,
7705 Condition
=> Make_Op_Not
(Loc
, Cond
),
7706 Then_Statements
=> New_List
(
7707 Make_Raise_Statement
(Loc
,
7710 (RTE
(RE_Assert_Failure
), Loc
)))));
7712 -- Failed check with message indicating the failed precondition and the
7713 -- call that caused it.
7716 Insert_Action
(Call_Node
,
7717 Make_If_Statement
(Loc
,
7718 Condition
=> Make_Op_Not
(Loc
, Cond
),
7719 Then_Statements
=> New_List
(
7720 Make_Procedure_Call_Statement
(Loc
,
7723 (RTE
(RE_Raise_Assert_Failure
), Loc
),
7724 Parameter_Associations
=>
7725 New_List
(Build_Error_Message
(Subp
))))));
7727 end Install_Class_Preconditions_Check
;
7729 ------------------------------
7730 -- Is_Build_In_Place_Entity --
7731 ------------------------------
7733 function Is_Build_In_Place_Entity
(E
: Entity_Id
) return Boolean is
7734 Nam
: constant String := Get_Name_String
(Chars
(E
));
7736 function Has_Suffix
(Suffix
: String) return Boolean;
7737 -- Return True if Nam has suffix Suffix
7739 function Has_Suffix
(Suffix
: String) return Boolean is
7740 Len
: constant Natural := Suffix
'Length;
7742 return Nam
'Length > Len
7743 and then Nam
(Nam
'Last - Len
+ 1 .. Nam
'Last) = Suffix
;
7746 -- Start of processing for Is_Build_In_Place_Entity
7749 return Has_Suffix
(BIP_Alloc_Suffix
)
7750 or else Has_Suffix
(BIP_Storage_Pool_Suffix
)
7751 or else Has_Suffix
(BIP_Finalization_Master_Suffix
)
7752 or else Has_Suffix
(BIP_Task_Master_Suffix
)
7753 or else Has_Suffix
(BIP_Activation_Chain_Suffix
)
7754 or else Has_Suffix
(BIP_Object_Access_Suffix
);
7755 end Is_Build_In_Place_Entity
;
7757 --------------------------------
7758 -- Is_Build_In_Place_Function --
7759 --------------------------------
7761 function Is_Build_In_Place_Function
(E
: Entity_Id
) return Boolean is
7762 Kind
: constant Entity_Kind
:= Ekind
(E
);
7763 Typ
: constant Entity_Id
:= Etype
(E
);
7766 -- This function is called from Expand_Subtype_From_Expr during
7767 -- semantic analysis, even when expansion is off. In those cases
7768 -- the build_in_place expansion will not take place.
7770 if not Expander_Active
then
7774 -- We never use build-in-place if the convention is other than Ada,
7775 -- but note that it is OK for a build-in-place function to return a
7776 -- type with a foreign convention because the machinery ensures there
7779 return (Kind
in E_Function | E_Generic_Function
7781 (Kind
= E_Subprogram_Type
and then Typ
/= Standard_Void_Type
))
7782 and then Is_Build_In_Place_Result_Type
(Typ
)
7783 and then not Has_Foreign_Convention
(E
);
7784 end Is_Build_In_Place_Function
;
7786 -------------------------------------
7787 -- Is_Build_In_Place_Function_Call --
7788 -------------------------------------
7790 function Is_Build_In_Place_Function_Call
(N
: Node_Id
) return Boolean is
7791 Exp_Node
: constant Node_Id
:= Unqual_Conv
(N
);
7792 Function_Id
: Entity_Id
;
7795 -- Return False if the expander is currently inactive, since awareness
7796 -- of build-in-place treatment is only relevant during expansion. Note
7797 -- that Is_Build_In_Place_Function, which is called as part of this
7798 -- function, is also conditioned this way, but we need to check here as
7799 -- well to avoid blowing up on processing protected calls when expansion
7800 -- is disabled (such as with -gnatc) since those would trip over the
7801 -- raise of Program_Error below.
7803 -- In SPARK mode, build-in-place calls are not expanded, so that we
7804 -- may end up with a call that is neither resolved to an entity, nor
7805 -- an indirect call.
7807 if not Expander_Active
or else Nkind
(Exp_Node
) /= N_Function_Call
then
7811 if Is_Entity_Name
(Name
(Exp_Node
)) then
7812 Function_Id
:= Entity
(Name
(Exp_Node
));
7814 -- In the case of an explicitly dereferenced call, use the subprogram
7815 -- type generated for the dereference.
7817 elsif Nkind
(Name
(Exp_Node
)) = N_Explicit_Dereference
then
7818 Function_Id
:= Etype
(Name
(Exp_Node
));
7820 -- This may be a call to a protected function.
7822 elsif Nkind
(Name
(Exp_Node
)) = N_Selected_Component
then
7823 -- The selector in question might not have been analyzed due to a
7824 -- previous error, so analyze it here to output the appropriate
7825 -- error message instead of crashing when attempting to fetch its
7828 if not Analyzed
(Selector_Name
(Name
(Exp_Node
))) then
7829 Analyze
(Selector_Name
(Name
(Exp_Node
)));
7832 Function_Id
:= Etype
(Entity
(Selector_Name
(Name
(Exp_Node
))));
7835 raise Program_Error
;
7838 if Is_Build_In_Place_Function
(Function_Id
) then
7841 -- True also if the function has BIP Formals
7845 Kind
: constant Entity_Kind
:= Ekind
(Function_Id
);
7848 if (Kind
in E_Function | E_Generic_Function
7849 or else (Kind
= E_Subprogram_Type
7851 Etype
(Function_Id
) /= Standard_Void_Type
))
7852 and then Has_BIP_Formals
(Function_Id
)
7854 -- So we can stop here in the debugger
7861 end Is_Build_In_Place_Function_Call
;
7863 -----------------------------------
7864 -- Is_Build_In_Place_Result_Type --
7865 -----------------------------------
7867 function Is_Build_In_Place_Result_Type
(Typ
: Entity_Id
) return Boolean is
7869 if not Expander_Active
then
7873 -- In Ada 2005 all functions with an inherently limited return type
7874 -- must be handled using a build-in-place profile, including the case
7875 -- of a function with a limited interface result, where the function
7876 -- may return objects of nonlimited descendants.
7878 return Is_Limited_View
(Typ
)
7879 and then Ada_Version
>= Ada_2005
7880 and then not Debug_Flag_Dot_L
;
7881 end Is_Build_In_Place_Result_Type
;
7883 -------------------------------------
7884 -- Is_Build_In_Place_Return_Object --
7885 -------------------------------------
7887 function Is_Build_In_Place_Return_Object
(E
: Entity_Id
) return Boolean is
7889 return Is_Return_Object
(E
)
7890 and then Is_Build_In_Place_Function
(Return_Applies_To
(Scope
(E
)));
7891 end Is_Build_In_Place_Return_Object
;
7893 -----------------------------------
7894 -- Is_By_Reference_Return_Object --
7895 -----------------------------------
7897 function Is_By_Reference_Return_Object
(E
: Entity_Id
) return Boolean is
7899 return Is_Return_Object
(E
)
7900 and then Is_By_Reference_Type
(Etype
(Return_Applies_To
(Scope
(E
))));
7901 end Is_By_Reference_Return_Object
;
7903 -----------------------
7904 -- Is_Null_Procedure --
7905 -----------------------
7907 function Is_Null_Procedure
(Subp
: Entity_Id
) return Boolean is
7908 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
7911 if Ekind
(Subp
) /= E_Procedure
then
7914 -- Check if this is a declared null procedure
7916 elsif Nkind
(Decl
) = N_Subprogram_Declaration
then
7917 if not Null_Present
(Specification
(Decl
)) then
7920 elsif No
(Body_To_Inline
(Decl
)) then
7923 -- Check if the body contains only a null statement, followed by
7924 -- the return statement added during expansion.
7928 Orig_Bod
: constant Node_Id
:= Body_To_Inline
(Decl
);
7934 if Nkind
(Orig_Bod
) /= N_Subprogram_Body
then
7937 -- We must skip SCIL nodes because they are currently
7938 -- implemented as special N_Null_Statement nodes.
7942 (Statements
(Handled_Statement_Sequence
(Orig_Bod
)));
7943 Stat2
:= Next_Non_SCIL_Node
(Stat
);
7946 Is_Empty_List
(Declarations
(Orig_Bod
))
7947 and then Nkind
(Stat
) = N_Null_Statement
7951 (Nkind
(Stat2
) = N_Simple_Return_Statement
7952 and then No
(Next
(Stat2
))));
7960 end Is_Null_Procedure
;
7962 --------------------------------------
7963 -- Is_Secondary_Stack_Return_Object --
7964 --------------------------------------
7966 function Is_Secondary_Stack_Return_Object
(E
: Entity_Id
) return Boolean is
7968 return Is_Return_Object
(E
)
7969 and then Needs_Secondary_Stack
(Etype
(Return_Applies_To
(Scope
(E
))));
7970 end Is_Secondary_Stack_Return_Object
;
7972 ------------------------------
7973 -- Is_Special_Return_Object --
7974 ------------------------------
7976 function Is_Special_Return_Object
(E
: Entity_Id
) return Boolean is
7978 return Is_Build_In_Place_Return_Object
(E
)
7979 or else Is_Secondary_Stack_Return_Object
(E
)
7980 or else (Back_End_Return_Slot
7981 and then Is_By_Reference_Return_Object
(E
));
7982 end Is_Special_Return_Object
;
7984 -------------------------------------------
7985 -- Make_Build_In_Place_Call_In_Allocator --
7986 -------------------------------------------
7988 procedure Make_Build_In_Place_Call_In_Allocator
7989 (Allocator
: Node_Id
;
7990 Function_Call
: Node_Id
)
7992 Acc_Type
: constant Entity_Id
:= Etype
(Allocator
);
7993 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
7994 Func_Call
: Node_Id
:= Function_Call
;
7995 Ref_Func_Call
: Node_Id
;
7996 Function_Id
: Entity_Id
;
7997 Result_Subt
: Entity_Id
;
7998 New_Allocator
: Node_Id
;
7999 Return_Obj_Access
: Entity_Id
; -- temp for function result
8000 Temp_Init
: Node_Id
; -- initial value of Return_Obj_Access
8001 Alloc_Form
: BIP_Allocation_Form
;
8002 Pool
: Node_Id
; -- nonnull if Alloc_Form = User_Storage_Pool
8003 Return_Obj_Actual
: Node_Id
; -- the temp.all, in caller-allocates case
8004 Chain
: Entity_Id
; -- activation chain, in case of tasks
8007 -- Step past qualification or unchecked conversion (the latter can occur
8008 -- in cases of calls to 'Input).
8010 if Nkind
(Func_Call
) in N_Qualified_Expression
8012 | N_Unchecked_Type_Conversion
8014 Func_Call
:= Expression
(Func_Call
);
8017 -- Mark the call as processed as a build-in-place call
8019 pragma Assert
(not Is_Expanded_Build_In_Place_Call
(Func_Call
));
8020 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8022 if Is_Entity_Name
(Name
(Func_Call
)) then
8023 Function_Id
:= Entity
(Name
(Func_Call
));
8025 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8026 Function_Id
:= Etype
(Name
(Func_Call
));
8029 raise Program_Error
;
8032 Warn_BIP
(Func_Call
);
8034 Result_Subt
:= Available_View
(Etype
(Function_Id
));
8036 -- Create a temp for the function result. In the caller-allocates case,
8037 -- this will be initialized to the result of a new uninitialized
8038 -- allocator. Note: we do not use Allocator as the Related_Node of
8039 -- Return_Obj_Access in call to Make_Temporary below as this would
8040 -- create a sort of infinite "recursion".
8042 Return_Obj_Access
:= Make_Temporary
(Loc
, 'R');
8043 Set_Etype
(Return_Obj_Access
, Acc_Type
);
8044 Set_Can_Never_Be_Null
(Acc_Type
, False);
8045 -- It gets initialized to null, so we can't have that
8047 -- When the result subtype is constrained, the return object is created
8048 -- on the caller side, and access to it is passed to the function. This
8049 -- optimization is disabled when the result subtype needs finalization
8050 -- actions because the caller side allocation may result in undesirable
8051 -- finalization. Consider the following example:
8053 -- function Make_Lim_Ctrl return Lim_Ctrl is
8055 -- return Result : Lim_Ctrl := raise Program_Error do
8058 -- end Make_Lim_Ctrl;
8060 -- Obj : Lim_Ctrl_Ptr := new Lim_Ctrl'(Make_Lim_Ctrl);
8062 -- Even though the size of limited controlled type Lim_Ctrl is known,
8063 -- allocating Obj at the caller side will chain Obj on Lim_Ctrl_Ptr's
8064 -- finalization master. The subsequent call to Make_Lim_Ctrl will fail
8065 -- during the initialization actions for Result, which implies that
8066 -- Result (and Obj by extension) should not be finalized. However Obj
8067 -- will be finalized when access type Lim_Ctrl_Ptr goes out of scope
8068 -- since it is already attached on the related finalization master.
8070 -- Here and in related routines, we must examine the full view of the
8071 -- type, because the view at the point of call may differ from the
8072 -- one in the function body, and the expansion mechanism depends on
8073 -- the characteristics of the full view.
8075 if Needs_BIP_Alloc_Form
(Function_Id
) then
8078 -- Case of a user-defined storage pool. Pass an allocation parameter
8079 -- indicating that the function should allocate its result in the
8080 -- pool, and pass the pool. Use 'Unrestricted_Access because the
8081 -- pool may not be aliased.
8083 if Present
(Associated_Storage_Pool
(Acc_Type
)) then
8084 Alloc_Form
:= User_Storage_Pool
;
8086 Make_Attribute_Reference
(Loc
,
8089 (Associated_Storage_Pool
(Acc_Type
), Loc
),
8090 Attribute_Name
=> Name_Unrestricted_Access
);
8092 -- No user-defined pool; pass an allocation parameter indicating that
8093 -- the function should allocate its result on the heap.
8096 Alloc_Form
:= Global_Heap
;
8097 Pool
:= Make_Null
(No_Location
);
8100 -- The caller does not provide the return object in this case, so we
8101 -- have to pass null for the object access actual.
8103 Return_Obj_Actual
:= Empty
;
8106 -- Replace the initialized allocator of form "new T'(Func (...))"
8107 -- with an uninitialized allocator of form "new T", where T is the
8108 -- result subtype of the called function. The call to the function
8109 -- is handled separately further below.
8112 Make_Allocator
(Loc
,
8113 Expression
=> New_Occurrence_Of
(Result_Subt
, Loc
));
8114 Set_No_Initialization
(New_Allocator
);
8116 -- Copy attributes to new allocator. Note that the new allocator
8117 -- logically comes from source if the original one did, so copy the
8118 -- relevant flag. This ensures proper treatment of the restriction
8119 -- No_Implicit_Heap_Allocations in this case.
8121 Set_Storage_Pool
(New_Allocator
, Storage_Pool
(Allocator
));
8122 Set_Procedure_To_Call
(New_Allocator
, Procedure_To_Call
(Allocator
));
8123 Set_Comes_From_Source
(New_Allocator
, Comes_From_Source
(Allocator
));
8125 Rewrite
(Allocator
, New_Allocator
);
8127 -- Initial value of the temp is the result of the uninitialized
8128 -- allocator. Unchecked_Convert is needed for T'Input where T is
8129 -- derived from a controlled type.
8131 Temp_Init
:= Relocate_Node
(Allocator
);
8133 if Nkind
(Function_Call
) in
8134 N_Type_Conversion | N_Unchecked_Type_Conversion
8136 Temp_Init
:= Unchecked_Convert_To
(Acc_Type
, Temp_Init
);
8139 -- Indicate that caller allocates, and pass in the return object
8141 Alloc_Form
:= Caller_Allocation
;
8142 Pool
:= Make_Null
(No_Location
);
8143 Return_Obj_Actual
:= Unchecked_Convert_To
8145 Make_Explicit_Dereference
(Loc
,
8146 Prefix
=> New_Occurrence_Of
(Return_Obj_Access
, Loc
)));
8148 -- When the result subtype is unconstrained, the function itself must
8149 -- perform the allocation of the return object, so we pass parameters
8154 -- Declare the temp object
8156 Insert_Action
(Allocator
,
8157 Make_Object_Declaration
(Loc
,
8158 Defining_Identifier
=> Return_Obj_Access
,
8159 Object_Definition
=> New_Occurrence_Of
(Acc_Type
, Loc
),
8160 Expression
=> Temp_Init
));
8162 Ref_Func_Call
:= Make_Reference
(Loc
, Func_Call
);
8164 -- Ada 2005 (AI-251): If the type of the allocator is an interface
8165 -- then generate an implicit conversion to force displacement of the
8168 if Is_Interface
(Designated_Type
(Acc_Type
)) then
8171 OK_Convert_To
(Acc_Type
, Ref_Func_Call
));
8173 -- If the types are incompatible, we need an unchecked conversion. Note
8174 -- that the full types will be compatible, but the types not visibly
8177 elsif Nkind
(Function_Call
)
8178 in N_Type_Conversion | N_Unchecked_Type_Conversion
8180 Ref_Func_Call
:= Unchecked_Convert_To
(Acc_Type
, Ref_Func_Call
);
8184 Assign
: constant Node_Id
:=
8185 Make_Assignment_Statement
(Loc
,
8186 Name
=> New_Occurrence_Of
(Return_Obj_Access
, Loc
),
8187 Expression
=> Ref_Func_Call
);
8188 -- Assign the result of the function call into the temp. In the
8189 -- caller-allocates case, this is overwriting the temp with its
8190 -- initial value, which has no effect. In the callee-allocates case,
8191 -- this is setting the temp to point to the object allocated by the
8192 -- callee. Unchecked_Convert is needed for T'Input where T is derived
8193 -- from a controlled type.
8196 -- Actions to be inserted. If there are no tasks, this is just the
8197 -- assignment statement. If the allocated object has tasks, we need
8198 -- to wrap the assignment in a block that activates them. The
8199 -- activation chain of that block must be passed to the function,
8200 -- rather than some outer chain.
8203 if Might_Have_Tasks
(Result_Subt
) then
8204 Actions
:= New_List
;
8205 Build_Task_Allocate_Block_With_Init_Stmts
8206 (Actions
, Allocator
, Init_Stmts
=> New_List
(Assign
));
8207 Chain
:= Activation_Chain_Entity
(Last
(Actions
));
8209 Actions
:= New_List
(Assign
);
8213 Insert_Actions
(Allocator
, Actions
);
8216 -- When the function has a controlling result, an allocation-form
8217 -- parameter must be passed indicating that the caller is allocating
8218 -- the result object. This is needed because such a function can be
8219 -- called as a dispatching operation and must be treated similarly
8220 -- to functions with unconstrained result subtypes.
8222 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8223 (Func_Call
, Function_Id
, Alloc_Form
, Pool_Actual
=> Pool
);
8225 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8226 (Func_Call
, Function_Id
, Acc_Type
);
8228 Add_Task_Actuals_To_Build_In_Place_Call
8229 (Func_Call
, Function_Id
, Master_Actual
=> Master_Id
(Acc_Type
),
8232 -- Add an implicit actual to the function call that provides access
8233 -- to the allocated object. An unchecked conversion to the (specific)
8234 -- result subtype of the function is inserted to handle cases where
8235 -- the access type of the allocator has a class-wide designated type.
8237 Add_Access_Actual_To_Build_In_Place_Call
8238 (Func_Call
, Function_Id
, Return_Obj_Actual
);
8240 -- Finally, replace the allocator node with a reference to the temp
8242 Rewrite
(Allocator
, New_Occurrence_Of
(Return_Obj_Access
, Loc
));
8244 Analyze_And_Resolve
(Allocator
, Acc_Type
);
8245 pragma Assert
(Check_Number_Of_Actuals
(Func_Call
, Function_Id
));
8246 pragma Assert
(Check_BIP_Actuals
(Func_Call
, Function_Id
));
8247 end Make_Build_In_Place_Call_In_Allocator
;
8249 ---------------------------------------------------
8250 -- Make_Build_In_Place_Call_In_Anonymous_Context --
8251 ---------------------------------------------------
8253 procedure Make_Build_In_Place_Call_In_Anonymous_Context
8254 (Function_Call
: Node_Id
)
8256 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8257 Func_Call
: constant Node_Id
:= Unqual_Conv
(Function_Call
);
8258 Function_Id
: Entity_Id
;
8259 Result_Subt
: Entity_Id
;
8260 Return_Obj_Id
: Entity_Id
;
8261 Return_Obj_Decl
: Entity_Id
;
8264 -- If the call has already been processed to add build-in-place actuals
8265 -- then return. One place this can occur is for calls to build-in-place
8266 -- functions that occur within a call to a protected operation, where
8267 -- due to rewriting and expansion of the protected call there can be
8268 -- more than one call to Expand_Actuals for the same set of actuals.
8270 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8274 -- Mark the call as processed as a build-in-place call
8276 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8278 if Is_Entity_Name
(Name
(Func_Call
)) then
8279 Function_Id
:= Entity
(Name
(Func_Call
));
8281 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8282 Function_Id
:= Etype
(Name
(Func_Call
));
8285 raise Program_Error
;
8288 Warn_BIP
(Func_Call
);
8290 Result_Subt
:= Etype
(Function_Id
);
8292 -- If the build-in-place function returns a controlled object, then the
8293 -- object needs to be finalized immediately after the context. Since
8294 -- this case produces a transient scope, the servicing finalizer needs
8295 -- to name the returned object. Create a temporary which is initialized
8296 -- with the function call:
8298 -- Temp_Id : Func_Type := BIP_Func_Call;
8300 -- The initialization expression of the temporary will be rewritten by
8301 -- the expander using the appropriate mechanism in Make_Build_In_Place_
8302 -- Call_In_Object_Declaration.
8304 if Needs_Finalization
(Result_Subt
) then
8306 Temp_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'R');
8307 Temp_Decl
: Node_Id
;
8310 -- Reset the guard on the function call since the following does
8311 -- not perform actual call expansion.
8313 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
, False);
8316 Make_Object_Declaration
(Loc
,
8317 Defining_Identifier
=> Temp_Id
,
8318 Object_Definition
=>
8319 New_Occurrence_Of
(Result_Subt
, Loc
),
8321 New_Copy_Tree
(Function_Call
));
8323 Insert_Action
(Function_Call
, Temp_Decl
);
8325 Rewrite
(Function_Call
, New_Occurrence_Of
(Temp_Id
, Loc
));
8326 Analyze
(Function_Call
);
8329 -- When the result subtype is definite, an object of the subtype is
8330 -- declared and an access value designating it is passed as an actual.
8332 elsif Caller_Known_Size
(Func_Call
, Result_Subt
) then
8334 -- Create a temporary object to hold the function result
8336 Return_Obj_Id
:= Make_Temporary
(Loc
, 'R');
8337 Set_Etype
(Return_Obj_Id
, Result_Subt
);
8340 Make_Object_Declaration
(Loc
,
8341 Defining_Identifier
=> Return_Obj_Id
,
8342 Aliased_Present
=> True,
8343 Object_Definition
=> New_Occurrence_Of
(Result_Subt
, Loc
));
8345 Set_No_Initialization
(Return_Obj_Decl
);
8347 Insert_Action
(Func_Call
, Return_Obj_Decl
);
8349 -- When the function has a controlling result, an allocation-form
8350 -- parameter must be passed indicating that the caller is allocating
8351 -- the result object. This is needed because such a function can be
8352 -- called as a dispatching operation and must be treated similarly
8353 -- to functions with unconstrained result subtypes.
8355 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8356 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8358 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8359 (Func_Call
, Function_Id
);
8361 Add_Task_Actuals_To_Build_In_Place_Call
8362 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8364 -- Add an implicit actual to the function call that provides access
8365 -- to the caller's return object.
8367 Add_Access_Actual_To_Build_In_Place_Call
8368 (Func_Call
, Function_Id
, New_Occurrence_Of
(Return_Obj_Id
, Loc
));
8370 pragma Assert
(Check_Number_Of_Actuals
(Func_Call
, Function_Id
));
8371 pragma Assert
(Check_BIP_Actuals
(Func_Call
, Function_Id
));
8373 -- When the result subtype is unconstrained, the function must allocate
8374 -- the return object in the secondary stack, so appropriate implicit
8375 -- parameters are added to the call to indicate that. A transient
8376 -- scope is established to ensure eventual cleanup of the result.
8379 -- Pass an allocation parameter indicating that the function should
8380 -- allocate its result on the secondary stack.
8382 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8383 (Func_Call
, Function_Id
, Alloc_Form
=> Secondary_Stack
);
8385 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8386 (Func_Call
, Function_Id
);
8388 Add_Task_Actuals_To_Build_In_Place_Call
8389 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8391 -- Pass a null value to the function since no return object is
8392 -- available on the caller side.
8394 Add_Access_Actual_To_Build_In_Place_Call
8395 (Func_Call
, Function_Id
, Empty
);
8397 pragma Assert
(Check_Number_Of_Actuals
(Func_Call
, Function_Id
));
8398 pragma Assert
(Check_BIP_Actuals
(Func_Call
, Function_Id
));
8400 end Make_Build_In_Place_Call_In_Anonymous_Context
;
8402 --------------------------------------------
8403 -- Make_Build_In_Place_Call_In_Assignment --
8404 --------------------------------------------
8406 procedure Make_Build_In_Place_Call_In_Assignment
8408 Function_Call
: Node_Id
)
8410 Func_Call
: constant Node_Id
:= Unqual_Conv
(Function_Call
);
8411 Lhs
: constant Node_Id
:= Name
(Assign
);
8412 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8413 Func_Id
: Entity_Id
;
8416 Ptr_Typ
: Entity_Id
;
8417 Ptr_Typ_Decl
: Node_Id
;
8419 Result_Subt
: Entity_Id
;
8422 -- Mark the call as processed as a build-in-place call
8424 pragma Assert
(not Is_Expanded_Build_In_Place_Call
(Func_Call
));
8425 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8427 if Is_Entity_Name
(Name
(Func_Call
)) then
8428 Func_Id
:= Entity
(Name
(Func_Call
));
8430 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8431 Func_Id
:= Etype
(Name
(Func_Call
));
8434 raise Program_Error
;
8437 Warn_BIP
(Func_Call
);
8439 Result_Subt
:= Etype
(Func_Id
);
8441 -- When the result subtype is unconstrained, an additional actual must
8442 -- be passed to indicate that the caller is providing the return object.
8443 -- This parameter must also be passed when the called function has a
8444 -- controlling result, because dispatching calls to the function needs
8445 -- to be treated effectively the same as calls to class-wide functions.
8447 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8448 (Func_Call
, Func_Id
, Alloc_Form
=> Caller_Allocation
);
8450 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8451 (Func_Call
, Func_Id
);
8453 Add_Task_Actuals_To_Build_In_Place_Call
8454 (Func_Call
, Func_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8456 -- Add an implicit actual to the function call that provides access to
8457 -- the caller's return object.
8459 Add_Access_Actual_To_Build_In_Place_Call
8460 (Func_Call
, Func_Id
, Unchecked_Convert_To
(Result_Subt
, Lhs
));
8462 -- Create an access type designating the function's result subtype
8464 Ptr_Typ
:= Make_Temporary
(Loc
, 'A');
8467 Make_Full_Type_Declaration
(Loc
,
8468 Defining_Identifier
=> Ptr_Typ
,
8470 Make_Access_To_Object_Definition
(Loc
,
8471 All_Present
=> True,
8472 Subtype_Indication
=>
8473 New_Occurrence_Of
(Result_Subt
, Loc
)));
8474 Insert_After_And_Analyze
(Assign
, Ptr_Typ_Decl
);
8476 -- Finally, create an access object initialized to a reference to the
8477 -- function call. We know this access value is non-null, so mark the
8478 -- entity accordingly to suppress junk access checks.
8480 New_Expr
:= Make_Reference
(Loc
, Relocate_Node
(Func_Call
));
8482 -- Add a conversion if it's the wrong type
8484 New_Expr
:= Unchecked_Convert_To
(Ptr_Typ
, New_Expr
);
8486 Obj_Id
:= Make_Temporary
(Loc
, 'R', New_Expr
);
8487 Set_Etype
(Obj_Id
, Ptr_Typ
);
8488 Set_Is_Known_Non_Null
(Obj_Id
);
8491 Make_Object_Declaration
(Loc
,
8492 Defining_Identifier
=> Obj_Id
,
8493 Object_Definition
=> New_Occurrence_Of
(Ptr_Typ
, Loc
),
8494 Expression
=> New_Expr
);
8495 Insert_After_And_Analyze
(Ptr_Typ_Decl
, Obj_Decl
);
8497 Rewrite
(Assign
, Make_Null_Statement
(Loc
));
8498 pragma Assert
(Check_Number_Of_Actuals
(Func_Call
, Func_Id
));
8499 pragma Assert
(Check_BIP_Actuals
(Func_Call
, Func_Id
));
8500 end Make_Build_In_Place_Call_In_Assignment
;
8502 ----------------------------------------------------
8503 -- Make_Build_In_Place_Call_In_Object_Declaration --
8504 ----------------------------------------------------
8506 procedure Make_Build_In_Place_Call_In_Object_Declaration
8507 (Obj_Decl
: Node_Id
;
8508 Function_Call
: Node_Id
)
8510 function Get_Function_Id
(Func_Call
: Node_Id
) return Entity_Id
;
8511 -- Get the value of Function_Id, below
8513 ---------------------
8514 -- Get_Function_Id --
8515 ---------------------
8517 function Get_Function_Id
(Func_Call
: Node_Id
) return Entity_Id
is
8519 if Is_Entity_Name
(Name
(Func_Call
)) then
8520 return Entity
(Name
(Func_Call
));
8522 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8523 return Etype
(Name
(Func_Call
));
8526 raise Program_Error
;
8528 end Get_Function_Id
;
8532 Func_Call
: constant Node_Id
:= Unqual_Conv
(Function_Call
);
8533 Function_Id
: constant Entity_Id
:= Get_Function_Id
(Func_Call
);
8534 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8535 Obj_Loc
: constant Source_Ptr
:= Sloc
(Obj_Decl
);
8536 Obj_Def_Id
: constant Entity_Id
:= Defining_Identifier
(Obj_Decl
);
8537 Obj_Typ
: constant Entity_Id
:= Etype
(Obj_Def_Id
);
8538 Encl_Func
: constant Entity_Id
:= Enclosing_Subprogram
(Obj_Def_Id
);
8539 Result_Subt
: constant Entity_Id
:= Etype
(Function_Id
);
8541 Call_Deref
: Node_Id
;
8542 Caller_Object
: Node_Id
;
8544 Designated_Type
: Entity_Id
;
8545 Fmaster_Actual
: Node_Id
:= Empty
;
8546 Pool_Actual
: Node_Id
;
8547 Ptr_Typ
: Entity_Id
;
8548 Ptr_Typ_Decl
: Node_Id
;
8549 Pass_Caller_Acc
: Boolean := False;
8552 Definite
: constant Boolean :=
8553 Caller_Known_Size
(Func_Call
, Result_Subt
)
8554 and then not Is_Class_Wide_Type
(Obj_Typ
);
8555 -- In the case of "X : T'Class := F(...);", where F returns a
8556 -- Caller_Known_Size (specific) tagged type, we treat it as
8557 -- indefinite, because the code for the Definite case below sets the
8558 -- initialization expression of the object to Empty, which would be
8559 -- illegal Ada, and would cause gigi to misallocate X.
8561 Is_OK_Return_Object
: constant Boolean :=
8562 Is_Return_Object
(Obj_Def_Id
)
8564 not Has_Foreign_Convention
(Return_Applies_To
(Scope
(Obj_Def_Id
)));
8566 -- Start of processing for Make_Build_In_Place_Call_In_Object_Declaration
8569 -- If the call has already been processed to add build-in-place actuals
8572 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8576 -- Mark the call as processed as a build-in-place call
8578 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8580 Warn_BIP
(Func_Call
);
8582 -- Create an access type designating the function's result subtype.
8583 -- We use the type of the original call because it may be a call to an
8584 -- inherited operation, which the expansion has replaced with the parent
8585 -- operation that yields the parent type. Note that this access type
8586 -- must be declared before we establish a transient scope, so that it
8587 -- receives the proper accessibility level.
8589 if Is_Class_Wide_Type
(Obj_Typ
)
8590 and then not Is_Interface
(Obj_Typ
)
8591 and then not Is_Class_Wide_Type
(Etype
(Function_Call
))
8593 Designated_Type
:= Obj_Typ
;
8595 Designated_Type
:= Etype
(Function_Call
);
8598 Ptr_Typ
:= Make_Temporary
(Loc
, 'A');
8600 Make_Full_Type_Declaration
(Loc
,
8601 Defining_Identifier
=> Ptr_Typ
,
8603 Make_Access_To_Object_Definition
(Loc
,
8604 All_Present
=> True,
8605 Subtype_Indication
=>
8606 New_Occurrence_Of
(Designated_Type
, Loc
)));
8608 -- The access type and its accompanying object must be inserted after
8609 -- the object declaration in the constrained case, so that the function
8610 -- call can be passed access to the object. In the indefinite case, or
8611 -- if the object declaration is for a return object, the access type and
8612 -- object must be inserted before the object, since the object
8613 -- declaration is rewritten to be a renaming of a dereference of the
8614 -- access object. Note: we need to freeze Ptr_Typ explicitly, because
8615 -- the result object is in a different (transient) scope, so won't cause
8618 if Definite
and then not Is_OK_Return_Object
then
8620 -- The presence of an address clause complicates the build-in-place
8621 -- expansion because the indicated address must be processed before
8622 -- the indirect call is generated (including the definition of a
8623 -- local pointer to the object). The address clause may come from
8624 -- an aspect specification or from an explicit attribute
8625 -- specification appearing after the object declaration. These two
8626 -- cases require different processing.
8628 if Has_Aspect
(Obj_Def_Id
, Aspect_Address
) then
8630 -- Skip non-delayed pragmas that correspond to other aspects, if
8631 -- any, to find proper insertion point for freeze node of object.
8634 D
: Node_Id
:= Obj_Decl
;
8635 N
: Node_Id
:= Next
(D
);
8639 and then Nkind
(N
) in N_Attribute_Reference | N_Pragma
8646 Insert_After
(D
, Ptr_Typ_Decl
);
8648 -- Freeze object before pointer declaration, to ensure that
8649 -- generated attribute for address is inserted at the proper
8652 Freeze_Before
(Ptr_Typ_Decl
, Obj_Def_Id
);
8655 Analyze
(Ptr_Typ_Decl
);
8657 elsif Present
(Following_Address_Clause
(Obj_Decl
)) then
8659 -- Locate explicit address clause, which may also follow pragmas
8660 -- generated by other aspect specifications.
8663 Addr
: constant Node_Id
:= Following_Address_Clause
(Obj_Decl
);
8664 D
: Node_Id
:= Next
(Obj_Decl
);
8667 while Present
(D
) loop
8673 Insert_After_And_Analyze
(Addr
, Ptr_Typ_Decl
);
8677 Insert_After_And_Analyze
(Obj_Decl
, Ptr_Typ_Decl
);
8680 Insert_Action
(Obj_Decl
, Ptr_Typ_Decl
);
8683 -- Force immediate freezing of Ptr_Typ because Res_Decl will be
8684 -- elaborated in an inner (transient) scope and thus won't cause
8685 -- freezing by itself. It's not an itype, but it needs to be frozen
8686 -- inside the current subprogram (see Freeze_Outside in freeze.adb).
8688 Freeze_Itype
(Ptr_Typ
, Ptr_Typ_Decl
);
8690 -- If the object is a return object of an enclosing build-in-place
8691 -- function, then the implicit build-in-place parameters of the
8692 -- enclosing function are simply passed along to the called function.
8693 -- (Unfortunately, this won't cover the case of extension aggregates
8694 -- where the ancestor part is a build-in-place indefinite function
8695 -- call that should be passed along the caller's parameters.
8696 -- Currently those get mishandled by reassigning the result of the
8697 -- call to the aggregate return object, when the call result should
8698 -- really be directly built in place in the aggregate and not in a
8701 if Is_OK_Return_Object
then
8702 Pass_Caller_Acc
:= True;
8704 -- When the enclosing function has a BIP_Alloc_Form formal then we
8705 -- pass it along to the callee (such as when the enclosing function
8706 -- has an unconstrained or tagged result type).
8708 if Needs_BIP_Alloc_Form
(Encl_Func
) then
8709 if RTE_Available
(RE_Root_Storage_Pool_Ptr
) then
8712 (Build_In_Place_Formal
8713 (Encl_Func
, BIP_Storage_Pool
), Loc
);
8715 -- The build-in-place pool formal is not built on e.g. ZFP
8718 Pool_Actual
:= Empty
;
8721 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8722 (Function_Call
=> Func_Call
,
8723 Function_Id
=> Function_Id
,
8726 (Build_In_Place_Formal
(Encl_Func
, BIP_Alloc_Form
), Loc
),
8727 Pool_Actual
=> Pool_Actual
);
8729 -- Otherwise, if enclosing function has a definite result subtype,
8730 -- then caller allocation will be used.
8733 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8734 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8737 if Needs_BIP_Finalization_Master
(Encl_Func
) then
8740 (Build_In_Place_Formal
8741 (Encl_Func
, BIP_Finalization_Master
), Loc
);
8744 -- Retrieve the BIPacc formal from the enclosing function and convert
8745 -- it to the access type of the callee's BIP_Object_Access formal.
8748 Unchecked_Convert_To
8749 (Etype
(Build_In_Place_Formal
(Function_Id
, BIP_Object_Access
)),
8751 (Build_In_Place_Formal
(Encl_Func
, BIP_Object_Access
), Loc
));
8753 -- In the definite case, add an implicit actual to the function call
8754 -- that provides access to the declared object. An unchecked conversion
8755 -- to the (specific) result type of the function is inserted to handle
8756 -- the case where the object is declared with a class-wide type.
8759 Caller_Object
:= Unchecked_Convert_To
8760 (Result_Subt
, New_Occurrence_Of
(Obj_Def_Id
, Loc
));
8762 -- When the function has a controlling result, an allocation-form
8763 -- parameter must be passed indicating that the caller is allocating
8764 -- the result object. This is needed because such a function can be
8765 -- called as a dispatching operation and must be treated similarly to
8766 -- functions with indefinite result subtypes.
8768 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8769 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8771 -- The allocation for indefinite library-level objects occurs on the
8772 -- heap as opposed to the secondary stack. This accommodates DLLs where
8773 -- the secondary stack is destroyed after each library unload. This is a
8774 -- hybrid mechanism where a stack-allocated object lives on the heap.
8776 elsif Is_Library_Level_Entity
(Obj_Def_Id
)
8777 and then not Restriction_Active
(No_Implicit_Heap_Allocations
)
8779 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8780 (Func_Call
, Function_Id
, Alloc_Form
=> Global_Heap
);
8781 Caller_Object
:= Empty
;
8783 -- Create a finalization master for the access result type to ensure
8784 -- that the heap allocation can properly chain the object and later
8785 -- finalize it when the library unit goes out of scope.
8787 if Needs_Finalization
(Etype
(Func_Call
)) then
8788 Build_Finalization_Master
8790 For_Lib_Level
=> True,
8791 Insertion_Node
=> Ptr_Typ_Decl
);
8794 Make_Attribute_Reference
(Loc
,
8796 New_Occurrence_Of
(Finalization_Master
(Ptr_Typ
), Loc
),
8797 Attribute_Name
=> Name_Unrestricted_Access
);
8800 -- In other indefinite cases, pass an indication to do the allocation
8801 -- on the secondary stack and set Caller_Object to Empty so that a null
8802 -- value will be passed for the caller's object address. A transient
8803 -- scope is established to ensure eventual cleanup of the result.
8806 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8807 (Func_Call
, Function_Id
, Alloc_Form
=> Secondary_Stack
);
8808 Caller_Object
:= Empty
;
8810 Establish_Transient_Scope
(Obj_Decl
, Manage_Sec_Stack
=> True);
8813 -- Pass along any finalization master actual, which is needed in the
8814 -- case where the called function initializes a return object of an
8815 -- enclosing build-in-place function.
8817 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8818 (Func_Call
=> Func_Call
,
8819 Func_Id
=> Function_Id
,
8820 Master_Exp
=> Fmaster_Actual
);
8822 if Nkind
(Parent
(Obj_Decl
)) = N_Extended_Return_Statement
8823 and then Needs_BIP_Task_Actuals
(Function_Id
)
8825 -- Here we're passing along the master that was passed in to this
8828 Add_Task_Actuals_To_Build_In_Place_Call
8829 (Func_Call
, Function_Id
,
8832 (Build_In_Place_Formal
(Encl_Func
, BIP_Task_Master
), Loc
));
8835 Add_Task_Actuals_To_Build_In_Place_Call
8836 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8839 Add_Access_Actual_To_Build_In_Place_Call
8843 Is_Access
=> Pass_Caller_Acc
);
8845 -- Finally, create an access object initialized to a reference to the
8846 -- function call. We know this access value cannot be null, so mark the
8847 -- entity accordingly to suppress the access check. We need to suppress
8848 -- warnings, because this can be part of the expansion of "for ... of"
8849 -- and similar constructs that generate finalization actions. Such
8850 -- finalization actions are safe, because they check a count that
8851 -- indicates which objects should be finalized, but the back end
8852 -- nonetheless warns about uninitialized objects.
8854 Def_Id
:= Make_Temporary
(Loc
, 'R', Func_Call
);
8855 Set_Warnings_Off
(Def_Id
);
8856 Set_Etype
(Def_Id
, Ptr_Typ
);
8857 Set_Is_Known_Non_Null
(Def_Id
);
8859 if Nkind
(Function_Call
) in N_Type_Conversion
8860 | N_Unchecked_Type_Conversion
8863 Make_Object_Declaration
(Loc
,
8864 Defining_Identifier
=> Def_Id
,
8865 Constant_Present
=> True,
8866 Object_Definition
=> New_Occurrence_Of
(Ptr_Typ
, Loc
),
8868 Unchecked_Convert_To
8869 (Ptr_Typ
, Make_Reference
(Loc
, Relocate_Node
(Func_Call
))));
8872 Make_Object_Declaration
(Loc
,
8873 Defining_Identifier
=> Def_Id
,
8874 Constant_Present
=> True,
8875 Object_Definition
=> New_Occurrence_Of
(Ptr_Typ
, Loc
),
8877 Make_Reference
(Loc
, Relocate_Node
(Func_Call
)));
8880 Insert_After_And_Analyze
(Ptr_Typ_Decl
, Res_Decl
);
8882 -- If the result subtype of the called function is definite and is not
8883 -- itself the return expression of an enclosing BIP function, then mark
8884 -- the object as having no initialization.
8886 if Definite
and then not Is_OK_Return_Object
then
8888 -- The related object declaration is encased in a transient block
8889 -- because the build-in-place function call contains at least one
8890 -- nested function call that produces a controlled transient
8893 -- Obj : ... := BIP_Func_Call (Ctrl_Func_Call);
8895 -- Since the build-in-place expansion decouples the call from the
8896 -- object declaration, the finalization machinery lacks the context
8897 -- which prompted the generation of the transient block. To resolve
8898 -- this scenario, store the build-in-place call.
8900 if Scope_Is_Transient
then
8901 Set_BIP_Initialization_Call
(Obj_Def_Id
, Res_Decl
);
8904 Set_Expression
(Obj_Decl
, Empty
);
8905 Set_No_Initialization
(Obj_Decl
);
8907 -- In case of an indefinite result subtype, or if the call is the
8908 -- return expression of an enclosing BIP function, rewrite the object
8909 -- declaration as an object renaming where the renamed object is a
8910 -- dereference of <function_Call>'reference:
8912 -- Obj : Subt renames <function_call>'Ref.all;
8916 Make_Explicit_Dereference
(Obj_Loc
,
8917 Prefix
=> New_Occurrence_Of
(Def_Id
, Obj_Loc
));
8920 Make_Object_Renaming_Declaration
(Obj_Loc
,
8921 Defining_Identifier
=> Make_Temporary
(Obj_Loc
, 'D'),
8923 New_Occurrence_Of
(Designated_Type
, Obj_Loc
),
8924 Name
=> Call_Deref
));
8926 -- At this point, Defining_Identifier (Obj_Decl) is no longer equal
8929 pragma Assert
(Ekind
(Defining_Identifier
(Obj_Decl
)) = E_Void
);
8930 Set_Renamed_Object_Of_Possibly_Void
8931 (Defining_Identifier
(Obj_Decl
), Call_Deref
);
8933 -- If the original entity comes from source, then mark the new
8934 -- entity as needing debug information, even though it's defined
8935 -- by a generated renaming that does not come from source, so that
8936 -- the Materialize_Entity flag will be set on the entity when
8937 -- Debug_Renaming_Declaration is called during analysis.
8939 if Comes_From_Source
(Obj_Def_Id
) then
8940 Set_Debug_Info_Needed
(Defining_Identifier
(Obj_Decl
));
8944 Replace_Renaming_Declaration_Id
8945 (Obj_Decl
, Original_Node
(Obj_Decl
));
8948 pragma Assert
(Check_Number_Of_Actuals
(Func_Call
, Function_Id
));
8949 pragma Assert
(Check_BIP_Actuals
(Func_Call
, Function_Id
));
8950 end Make_Build_In_Place_Call_In_Object_Declaration
;
8952 -------------------------------------------------
8953 -- Make_Build_In_Place_Iface_Call_In_Allocator --
8954 -------------------------------------------------
8956 procedure Make_Build_In_Place_Iface_Call_In_Allocator
8957 (Allocator
: Node_Id
;
8958 Function_Call
: Node_Id
)
8960 BIP_Func_Call
: constant Node_Id
:=
8961 Unqual_BIP_Iface_Function_Call
(Function_Call
);
8962 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
8964 Anon_Type
: Entity_Id
;
8969 -- No action if the call has already been processed
8971 if Is_Expanded_Build_In_Place_Call
(BIP_Func_Call
) then
8975 Tmp_Id
:= Make_Temporary
(Loc
, 'D');
8977 -- Insert a temporary before N initialized with the BIP function call
8978 -- without its enclosing type conversions and analyze it without its
8979 -- expansion. This temporary facilitates us reusing the BIP machinery,
8980 -- which takes care of adding the extra build-in-place actuals and
8981 -- transforms this object declaration into an object renaming
8984 Anon_Type
:= Create_Itype
(E_Anonymous_Access_Type
, Function_Call
);
8985 Set_Directly_Designated_Type
(Anon_Type
, Etype
(BIP_Func_Call
));
8986 Set_Etype
(Anon_Type
, Anon_Type
);
8987 Build_Class_Wide_Master
(Anon_Type
);
8990 Make_Object_Declaration
(Loc
,
8991 Defining_Identifier
=> Tmp_Id
,
8992 Object_Definition
=> New_Occurrence_Of
(Anon_Type
, Loc
),
8994 Make_Allocator
(Loc
,
8996 Make_Qualified_Expression
(Loc
,
8998 New_Occurrence_Of
(Etype
(BIP_Func_Call
), Loc
),
8999 Expression
=> New_Copy_Tree
(BIP_Func_Call
))));
9001 -- Manually set the associated node for the anonymous access type to
9002 -- be its local declaration, to avoid confusing and complicating
9003 -- the accessibility machinery.
9005 Set_Associated_Node_For_Itype
(Anon_Type
, Tmp_Decl
);
9007 Expander_Mode_Save_And_Set
(False);
9008 Insert_Action
(Allocator
, Tmp_Decl
);
9009 Expander_Mode_Restore
;
9011 Make_Build_In_Place_Call_In_Allocator
9012 (Allocator
=> Expression
(Tmp_Decl
),
9013 Function_Call
=> Expression
(Expression
(Tmp_Decl
)));
9015 -- Add a conversion to displace the pointer to the allocated object
9016 -- to reference the corresponding dispatch table.
9019 Convert_To
(Etype
(Allocator
),
9020 New_Occurrence_Of
(Tmp_Id
, Loc
)));
9021 end Make_Build_In_Place_Iface_Call_In_Allocator
;
9023 ---------------------------------------------------------
9024 -- Make_Build_In_Place_Iface_Call_In_Anonymous_Context --
9025 ---------------------------------------------------------
9027 procedure Make_Build_In_Place_Iface_Call_In_Anonymous_Context
9028 (Function_Call
: Node_Id
)
9030 BIP_Func_Call
: constant Node_Id
:=
9031 Unqual_BIP_Iface_Function_Call
(Function_Call
);
9032 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
9038 -- No action of the call has already been processed
9040 if Is_Expanded_Build_In_Place_Call
(BIP_Func_Call
) then
9044 pragma Assert
(Needs_Finalization
(Etype
(BIP_Func_Call
)));
9046 -- Insert a temporary before the call initialized with function call to
9047 -- reuse the BIP machinery which takes care of adding the extra build-in
9048 -- place actuals and transforms this object declaration into an object
9049 -- renaming declaration.
9051 Tmp_Id
:= Make_Temporary
(Loc
, 'D');
9054 Make_Object_Declaration
(Loc
,
9055 Defining_Identifier
=> Tmp_Id
,
9056 Object_Definition
=>
9057 New_Occurrence_Of
(Etype
(Function_Call
), Loc
),
9058 Expression
=> Relocate_Node
(Function_Call
));
9060 Expander_Mode_Save_And_Set
(False);
9061 Insert_Action
(Function_Call
, Tmp_Decl
);
9062 Expander_Mode_Restore
;
9064 Make_Build_In_Place_Iface_Call_In_Object_Declaration
9065 (Obj_Decl
=> Tmp_Decl
,
9066 Function_Call
=> Expression
(Tmp_Decl
));
9067 end Make_Build_In_Place_Iface_Call_In_Anonymous_Context
;
9069 ----------------------------------------------------------
9070 -- Make_Build_In_Place_Iface_Call_In_Object_Declaration --
9071 ----------------------------------------------------------
9073 procedure Make_Build_In_Place_Iface_Call_In_Object_Declaration
9074 (Obj_Decl
: Node_Id
;
9075 Function_Call
: Node_Id
)
9077 BIP_Func_Call
: constant Node_Id
:=
9078 Unqual_BIP_Iface_Function_Call
(Function_Call
);
9079 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
9080 Obj_Id
: constant Entity_Id
:= Defining_Entity
(Obj_Decl
);
9086 -- No action of the call has already been processed
9088 if Is_Expanded_Build_In_Place_Call
(BIP_Func_Call
) then
9092 Tmp_Id
:= Make_Temporary
(Loc
, 'D');
9094 -- Insert a temporary before N initialized with the BIP function call
9095 -- without its enclosing type conversions and analyze it without its
9096 -- expansion. This temporary facilitates us reusing the BIP machinery,
9097 -- which takes care of adding the extra build-in-place actuals and
9098 -- transforms this object declaration into an object renaming
9102 Make_Object_Declaration
(Loc
,
9103 Defining_Identifier
=> Tmp_Id
,
9104 Object_Definition
=>
9105 New_Occurrence_Of
(Etype
(BIP_Func_Call
), Loc
),
9106 Expression
=> New_Copy_Tree
(BIP_Func_Call
));
9108 Expander_Mode_Save_And_Set
(False);
9109 Insert_Action
(Obj_Decl
, Tmp_Decl
);
9110 Expander_Mode_Restore
;
9112 Make_Build_In_Place_Call_In_Object_Declaration
9113 (Obj_Decl
=> Tmp_Decl
,
9114 Function_Call
=> Expression
(Tmp_Decl
));
9116 pragma Assert
(Nkind
(Tmp_Decl
) = N_Object_Renaming_Declaration
);
9118 -- Replace the original build-in-place function call by a reference to
9119 -- the resulting temporary object renaming declaration. In this way,
9120 -- all the interface conversions performed in the original Function_Call
9121 -- on the build-in-place object are preserved.
9123 Rewrite
(BIP_Func_Call
, New_Occurrence_Of
(Tmp_Id
, Loc
));
9125 -- Replace the original object declaration by an internal object
9126 -- renaming declaration. This leaves the generated code more clean (the
9127 -- build-in-place function call in an object renaming declaration and
9128 -- displacements of the pointer to the build-in-place object in another
9129 -- renaming declaration) and allows us to invoke the routine that takes
9130 -- care of replacing the identifier of the renaming declaration (routine
9131 -- originally developed for the regular build-in-place management).
9134 Make_Object_Renaming_Declaration
(Loc
,
9135 Defining_Identifier
=> Make_Temporary
(Loc
, 'D'),
9136 Subtype_Mark
=> New_Occurrence_Of
(Etype
(Obj_Id
), Loc
),
9137 Name
=> Function_Call
));
9140 Replace_Renaming_Declaration_Id
(Obj_Decl
, Original_Node
(Obj_Decl
));
9141 end Make_Build_In_Place_Iface_Call_In_Object_Declaration
;
9143 --------------------------------------------
9144 -- Make_CPP_Constructor_Call_In_Allocator --
9145 --------------------------------------------
9147 procedure Make_CPP_Constructor_Call_In_Allocator
9148 (Allocator
: Node_Id
;
9149 Function_Call
: Node_Id
)
9151 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
9152 Acc_Type
: constant Entity_Id
:= Etype
(Allocator
);
9153 Function_Id
: constant Entity_Id
:= Entity
(Name
(Function_Call
));
9154 Result_Subt
: constant Entity_Id
:= Available_View
(Etype
(Function_Id
));
9156 New_Allocator
: Node_Id
;
9157 Return_Obj_Access
: Entity_Id
;
9161 pragma Assert
(Nkind
(Allocator
) = N_Allocator
9162 and then Nkind
(Function_Call
) = N_Function_Call
);
9163 pragma Assert
(Convention
(Function_Id
) = Convention_CPP
9164 and then Is_Constructor
(Function_Id
));
9165 pragma Assert
(Is_Constrained
(Underlying_Type
(Result_Subt
)));
9167 -- Replace the initialized allocator of form "new T'(Func (...))" with
9168 -- an uninitialized allocator of form "new T", where T is the result
9169 -- subtype of the called function. The call to the function is handled
9170 -- separately further below.
9173 Make_Allocator
(Loc
,
9174 Expression
=> New_Occurrence_Of
(Result_Subt
, Loc
));
9175 Set_No_Initialization
(New_Allocator
);
9177 -- Copy attributes to new allocator. Note that the new allocator
9178 -- logically comes from source if the original one did, so copy the
9179 -- relevant flag. This ensures proper treatment of the restriction
9180 -- No_Implicit_Heap_Allocations in this case.
9182 Set_Storage_Pool
(New_Allocator
, Storage_Pool
(Allocator
));
9183 Set_Procedure_To_Call
(New_Allocator
, Procedure_To_Call
(Allocator
));
9184 Set_Comes_From_Source
(New_Allocator
, Comes_From_Source
(Allocator
));
9186 Rewrite
(Allocator
, New_Allocator
);
9188 -- Create a new access object and initialize it to the result of the
9189 -- new uninitialized allocator. Note: we do not use Allocator as the
9190 -- Related_Node of Return_Obj_Access in call to Make_Temporary below
9191 -- as this would create a sort of infinite "recursion".
9193 Return_Obj_Access
:= Make_Temporary
(Loc
, 'R');
9194 Set_Etype
(Return_Obj_Access
, Acc_Type
);
9197 -- Rnnn : constant ptr_T := new (T);
9198 -- Init (Rnn.all,...);
9201 Make_Object_Declaration
(Loc
,
9202 Defining_Identifier
=> Return_Obj_Access
,
9203 Constant_Present
=> True,
9204 Object_Definition
=> New_Occurrence_Of
(Acc_Type
, Loc
),
9205 Expression
=> Relocate_Node
(Allocator
));
9206 Insert_Action
(Allocator
, Tmp_Obj
);
9208 Insert_List_After_And_Analyze
(Tmp_Obj
,
9209 Build_Initialization_Call
(Loc
,
9211 Make_Explicit_Dereference
(Loc
,
9212 Prefix
=> New_Occurrence_Of
(Return_Obj_Access
, Loc
)),
9213 Typ
=> Etype
(Function_Id
),
9214 Constructor_Ref
=> Function_Call
));
9216 -- Finally, replace the allocator node with a reference to the result of
9217 -- the function call itself (which will effectively be an access to the
9218 -- object created by the allocator).
9220 Rewrite
(Allocator
, New_Occurrence_Of
(Return_Obj_Access
, Loc
));
9222 -- Ada 2005 (AI-251): If the type of the allocator is an interface then
9223 -- generate an implicit conversion to force displacement of the "this"
9226 if Is_Interface
(Designated_Type
(Acc_Type
)) then
9227 Rewrite
(Allocator
, Convert_To
(Acc_Type
, Relocate_Node
(Allocator
)));
9230 Analyze_And_Resolve
(Allocator
, Acc_Type
);
9231 end Make_CPP_Constructor_Call_In_Allocator
;
9233 ----------------------
9234 -- Might_Have_Tasks --
9235 ----------------------
9237 function Might_Have_Tasks
(Typ
: Entity_Id
) return Boolean is
9239 return not Global_No_Tasking
9240 and then not No_Run_Time_Mode
9241 and then (Has_Task
(Typ
)
9242 or else (Is_Class_Wide_Type
(Typ
)
9243 and then Is_Limited_Record
(Etype
(Typ
))
9244 and then not Has_Aspect
9245 (Etype
(Typ
), Aspect_No_Task_Parts
)));
9246 end Might_Have_Tasks
;
9248 ----------------------------
9249 -- Needs_BIP_Task_Actuals --
9250 ----------------------------
9252 function Needs_BIP_Task_Actuals
(Func_Id
: Entity_Id
) return Boolean is
9253 Subp_Id
: Entity_Id
;
9254 Func_Typ
: Entity_Id
;
9257 if Global_No_Tasking
or else No_Run_Time_Mode
then
9261 -- For thunks we must rely on their target entity; otherwise, given that
9262 -- the profile of thunks for functions returning a limited interface
9263 -- type returns a class-wide type, we would erroneously add these extra
9266 if Is_Thunk
(Func_Id
) then
9267 Subp_Id
:= Thunk_Target
(Func_Id
);
9275 Func_Typ
:= Underlying_Type
(Etype
(Subp_Id
));
9277 -- Functions returning types with foreign convention don't have extra
9280 if Has_Foreign_Convention
(Func_Typ
) then
9283 -- At first sight, for all the following cases, we could add assertions
9284 -- to ensure that if Func_Id is frozen then the computed result matches
9285 -- with the availability of the task master extra formal; unfortunately
9286 -- this is not feasible because we may be precisely freezing this entity
9287 -- (that is, Is_Frozen has been set by Freeze_Entity but it has not
9288 -- completed its work).
9290 elsif Has_Task
(Func_Typ
) then
9293 elsif Ekind
(Func_Id
) = E_Function
then
9294 return Might_Have_Tasks
(Func_Typ
);
9296 -- Handle subprogram type internally generated for dispatching call. We
9297 -- cannot rely on the return type of the subprogram type of dispatching
9298 -- calls since it is always a class-wide type (cf. Expand_Dispatching_
9301 elsif Ekind
(Func_Id
) = E_Subprogram_Type
then
9302 if Is_Dispatch_Table_Entity
(Func_Id
) then
9303 return Has_BIP_Extra_Formal
(Func_Id
, BIP_Task_Master
);
9305 return Might_Have_Tasks
(Func_Typ
);
9309 raise Program_Error
;
9311 end Needs_BIP_Task_Actuals
;
9313 -----------------------------------
9314 -- Needs_BIP_Finalization_Master --
9315 -----------------------------------
9317 function Needs_BIP_Finalization_Master
(Func_Id
: Entity_Id
) return Boolean
9319 Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
9322 -- A formal giving the finalization master is needed for build-in-place
9323 -- functions whose result type needs finalization or is a tagged type.
9324 -- Tagged primitive build-in-place functions need such a formal because
9325 -- they can be called by a dispatching call, and extensions may require
9326 -- finalization even if the root type doesn't. This means nonprimitive
9327 -- build-in-place functions with tagged results also need it, since such
9328 -- functions can be called via access-to-function types, and those can
9329 -- be used to call primitives, so the formal needs to be passed to all
9330 -- such build-in-place functions, primitive or not.
9332 return not Restriction_Active
(No_Finalization
)
9333 and then (Needs_Finalization
(Typ
) or else Is_Tagged_Type
(Typ
))
9334 and then not Has_Foreign_Convention
(Typ
);
9335 end Needs_BIP_Finalization_Master
;
9337 --------------------------
9338 -- Needs_BIP_Alloc_Form --
9339 --------------------------
9341 function Needs_BIP_Alloc_Form
(Func_Id
: Entity_Id
) return Boolean is
9342 Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
9345 -- A formal giving the allocation method is needed for build-in-place
9346 -- functions whose result type is returned on the secondary stack or
9347 -- is a tagged type. Tagged primitive build-in-place functions need
9348 -- such a formal because they can be called by a dispatching call, and
9349 -- the secondary stack is always used for dispatching-on-result calls.
9350 -- This means nonprimitive build-in-place functions with tagged results
9351 -- also need it, as such functions can be called via access-to-function
9352 -- types, and those can be used to call primitives, so the formal needs
9353 -- to be passed to all such build-in-place functions, primitive or not.
9355 return not Restriction_Active
(No_Secondary_Stack
)
9356 and then (Needs_Secondary_Stack
(Typ
) or else Is_Tagged_Type
(Typ
))
9357 and then not Has_Foreign_Convention
(Typ
);
9358 end Needs_BIP_Alloc_Form
;
9360 -------------------------------------
9361 -- Replace_Renaming_Declaration_Id --
9362 -------------------------------------
9364 procedure Replace_Renaming_Declaration_Id
9365 (New_Decl
: Node_Id
;
9366 Orig_Decl
: Node_Id
)
9368 New_Id
: constant Entity_Id
:= Defining_Entity
(New_Decl
);
9369 Orig_Id
: constant Entity_Id
:= Defining_Entity
(Orig_Decl
);
9372 Set_Chars
(New_Id
, Chars
(Orig_Id
));
9374 -- Swap next entity links in preparation for exchanging entities
9377 Next_Id
: constant Entity_Id
:= Next_Entity
(New_Id
);
9379 Link_Entities
(New_Id
, Next_Entity
(Orig_Id
));
9380 Link_Entities
(Orig_Id
, Next_Id
);
9383 Set_Homonym
(New_Id
, Homonym
(Orig_Id
));
9384 Exchange_Entities
(New_Id
, Orig_Id
);
9386 -- Preserve source indication of original declaration, so that xref
9387 -- information is properly generated for the right entity.
9389 Preserve_Comes_From_Source
(New_Decl
, Orig_Decl
);
9390 Preserve_Comes_From_Source
(Orig_Id
, Orig_Decl
);
9392 Set_Comes_From_Source
(New_Id
, False);
9394 -- Preserve aliased indication
9396 Set_Is_Aliased
(Orig_Id
, Is_Aliased
(New_Id
));
9397 end Replace_Renaming_Declaration_Id
;
9399 ---------------------------------
9400 -- Rewrite_Function_Call_For_C --
9401 ---------------------------------
9403 procedure Rewrite_Function_Call_For_C
(N
: Node_Id
) is
9404 Orig_Func
: constant Entity_Id
:= Entity
(Name
(N
));
9405 Func_Id
: constant Entity_Id
:= Ultimate_Alias
(Orig_Func
);
9406 Par
: constant Node_Id
:= Parent
(N
);
9407 Proc_Id
: constant Entity_Id
:= Corresponding_Procedure
(Func_Id
);
9408 Loc
: constant Source_Ptr
:= Sloc
(Par
);
9410 Last_Actual
: Node_Id
;
9411 Last_Formal
: Entity_Id
;
9413 -- Start of processing for Rewrite_Function_Call_For_C
9416 -- The actuals may be given by named associations, so the added actual
9417 -- that is the target of the return value of the call must be a named
9418 -- association as well, so we retrieve the name of the generated
9421 Last_Formal
:= First_Formal
(Proc_Id
);
9422 while Present
(Next_Formal
(Last_Formal
)) loop
9423 Next_Formal
(Last_Formal
);
9426 Actuals
:= Parameter_Associations
(N
);
9428 -- The original function may lack parameters
9430 if No
(Actuals
) then
9431 Actuals
:= New_List
;
9434 -- If the function call is the expression of an assignment statement,
9435 -- transform the assignment into a procedure call. Generate:
9437 -- LHS := Func_Call (...);
9439 -- Proc_Call (..., LHS);
9441 -- If function is inherited, a conversion may be necessary.
9443 if Nkind
(Par
) = N_Assignment_Statement
then
9444 Last_Actual
:= Name
(Par
);
9446 if not Comes_From_Source
(Orig_Func
)
9447 and then Etype
(Orig_Func
) /= Etype
(Func_Id
)
9450 Make_Type_Conversion
(Loc
,
9451 New_Occurrence_Of
(Etype
(Func_Id
), Loc
),
9456 Make_Parameter_Association
(Loc
,
9458 Make_Identifier
(Loc
, Chars
(Last_Formal
)),
9459 Explicit_Actual_Parameter
=> Last_Actual
));
9462 Make_Procedure_Call_Statement
(Loc
,
9463 Name
=> New_Occurrence_Of
(Proc_Id
, Loc
),
9464 Parameter_Associations
=> Actuals
));
9467 -- Otherwise the context is an expression. Generate a temporary and a
9468 -- procedure call to obtain the function result. Generate:
9470 -- ... Func_Call (...) ...
9473 -- Proc_Call (..., Temp);
9478 Temp_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
9487 Make_Object_Declaration
(Loc
,
9488 Defining_Identifier
=> Temp_Id
,
9489 Object_Definition
=>
9490 New_Occurrence_Of
(Etype
(Func_Id
), Loc
));
9493 -- Proc_Call (..., Temp);
9496 Make_Parameter_Association
(Loc
,
9498 Make_Identifier
(Loc
, Chars
(Last_Formal
)),
9499 Explicit_Actual_Parameter
=>
9500 New_Occurrence_Of
(Temp_Id
, Loc
)));
9503 Make_Procedure_Call_Statement
(Loc
,
9504 Name
=> New_Occurrence_Of
(Proc_Id
, Loc
),
9505 Parameter_Associations
=> Actuals
);
9507 Insert_Actions
(Par
, New_List
(Decl
, Call
));
9508 Rewrite
(N
, New_Occurrence_Of
(Temp_Id
, Loc
));
9511 end Rewrite_Function_Call_For_C
;
9513 ------------------------------------
9514 -- Set_Enclosing_Sec_Stack_Return --
9515 ------------------------------------
9517 procedure Set_Enclosing_Sec_Stack_Return
(N
: Node_Id
) is
9521 -- Due to a possible mix of internally generated blocks, source blocks
9522 -- and loops, the scope stack may not be contiguous as all labels are
9523 -- inserted at the top level within the related function. Instead,
9524 -- perform a parent-based traversal and mark all appropriate constructs.
9526 while Present
(P
) loop
9528 -- Mark the label of a source or internally generated block or
9531 if Nkind
(P
) in N_Block_Statement | N_Loop_Statement
then
9532 Set_Sec_Stack_Needed_For_Return
(Entity
(Identifier
(P
)));
9534 -- Mark the enclosing function
9536 elsif Nkind
(P
) = N_Subprogram_Body
then
9537 if Present
(Corresponding_Spec
(P
)) then
9538 Set_Sec_Stack_Needed_For_Return
(Corresponding_Spec
(P
));
9540 Set_Sec_Stack_Needed_For_Return
(Defining_Entity
(P
));
9543 -- Do not go beyond the enclosing function
9550 end Set_Enclosing_Sec_Stack_Return
;
9552 ------------------------------------
9553 -- Unqual_BIP_Iface_Function_Call --
9554 ------------------------------------
9556 function Unqual_BIP_Iface_Function_Call
(Expr
: Node_Id
) return Node_Id
is
9557 Has_Pointer_Displacement
: Boolean := False;
9558 On_Object_Declaration
: Boolean := False;
9559 -- Remember if processing the renaming expressions on recursion we have
9560 -- traversed an object declaration, since we can traverse many object
9561 -- declaration renamings but just one regular object declaration.
9563 function Unqual_BIP_Function_Call
(Expr
: Node_Id
) return Node_Id
;
9564 -- Search for a build-in-place function call skipping any qualification
9565 -- including qualified expressions, type conversions, references, calls
9566 -- to displace the pointer to the object, and renamings. Return Empty if
9567 -- no build-in-place function call is found.
9569 ------------------------------
9570 -- Unqual_BIP_Function_Call --
9571 ------------------------------
9573 function Unqual_BIP_Function_Call
(Expr
: Node_Id
) return Node_Id
is
9575 -- Recurse to handle case of multiple levels of qualification and/or
9578 if Nkind
(Expr
) in N_Qualified_Expression
9580 | N_Unchecked_Type_Conversion
9582 return Unqual_BIP_Function_Call
(Expression
(Expr
));
9584 -- Recurse to handle case of multiple levels of references and
9585 -- explicit dereferences.
9587 elsif Nkind
(Expr
) in N_Attribute_Reference
9588 | N_Explicit_Dereference
9591 return Unqual_BIP_Function_Call
(Prefix
(Expr
));
9593 -- Recurse on object renamings
9595 elsif Nkind
(Expr
) = N_Identifier
9596 and then Present
(Entity
(Expr
))
9597 and then Ekind
(Entity
(Expr
)) in E_Constant | E_Variable
9598 and then Nkind
(Parent
(Entity
(Expr
))) =
9599 N_Object_Renaming_Declaration
9600 and then Present
(Renamed_Object
(Entity
(Expr
)))
9602 return Unqual_BIP_Function_Call
(Renamed_Object
(Entity
(Expr
)));
9604 -- Recurse on the initializing expression of the first reference of
9605 -- an object declaration.
9607 elsif not On_Object_Declaration
9608 and then Nkind
(Expr
) = N_Identifier
9609 and then Present
(Entity
(Expr
))
9610 and then Ekind
(Entity
(Expr
)) in E_Constant | E_Variable
9611 and then Nkind
(Parent
(Entity
(Expr
))) = N_Object_Declaration
9612 and then Present
(Expression
(Parent
(Entity
(Expr
))))
9614 On_Object_Declaration
:= True;
9616 Unqual_BIP_Function_Call
(Expression
(Parent
(Entity
(Expr
))));
9618 -- Recurse to handle calls to displace the pointer to the object to
9619 -- reference a secondary dispatch table.
9621 elsif Nkind
(Expr
) = N_Function_Call
9622 and then Nkind
(Name
(Expr
)) in N_Has_Entity
9623 and then Present
(Entity
(Name
(Expr
)))
9624 and then Is_RTE
(Entity
(Name
(Expr
)), RE_Displace
)
9626 Has_Pointer_Displacement
:= True;
9628 Unqual_BIP_Function_Call
(First
(Parameter_Associations
(Expr
)));
9630 -- Normal case: check if the inner expression is a BIP function call
9631 -- and the pointer to the object is displaced.
9633 elsif Has_Pointer_Displacement
9634 and then Is_Build_In_Place_Function_Call
(Expr
)
9641 end Unqual_BIP_Function_Call
;
9643 -- Start of processing for Unqual_BIP_Iface_Function_Call
9646 if Nkind
(Expr
) = N_Identifier
and then No
(Entity
(Expr
)) then
9648 -- Can happen for X'Elab_Spec in the binder-generated file
9653 return Unqual_BIP_Function_Call
(Expr
);
9654 end Unqual_BIP_Iface_Function_Call
;
9656 -------------------------------
9657 -- Validate_Subprogram_Calls --
9658 -------------------------------
9660 procedure Validate_Subprogram_Calls
(N
: Node_Id
) is
9662 function Process_Node
(Nod
: Node_Id
) return Traverse_Result
;
9663 -- Function to traverse the subtree of N using Traverse_Proc.
9669 function Process_Node
(Nod
: Node_Id
) return Traverse_Result
is
9672 when N_Entry_Call_Statement
9673 | N_Procedure_Call_Statement
9677 Call_Node
: Node_Id
renames Nod
;
9681 -- Call using access to subprogram with explicit dereference
9683 if Nkind
(Name
(Call_Node
)) = N_Explicit_Dereference
then
9684 Subp
:= Etype
(Name
(Call_Node
));
9686 -- Prefix notation calls
9688 elsif Nkind
(Name
(Call_Node
)) = N_Selected_Component
then
9689 Subp
:= Entity
(Selector_Name
(Name
(Call_Node
)));
9691 -- Call to member of entry family, where Name is an indexed
9692 -- component, with the prefix being a selected component
9693 -- giving the task and entry family name, and the index
9694 -- being the entry index.
9696 elsif Nkind
(Name
(Call_Node
)) = N_Indexed_Component
then
9698 Entity
(Selector_Name
(Prefix
(Name
(Call_Node
))));
9703 Subp
:= Entity
(Name
(Call_Node
));
9706 pragma Assert
(Check_BIP_Actuals
(Call_Node
, Subp
));
9709 -- Skip generic bodies
9711 when N_Package_Body
=>
9712 if Ekind
(Unique_Defining_Entity
(Nod
)) = E_Generic_Package
then
9716 when N_Subprogram_Body
=>
9717 if Ekind
(Unique_Defining_Entity
(Nod
)) in E_Generic_Function
9718 | E_Generic_Procedure
9723 -- Nodes we want to ignore
9725 -- Skip calls placed in the full declaration of record types since
9726 -- the call will be performed by their Init Proc; for example,
9727 -- calls initializing default values of discriminants or calls
9728 -- providing the initial value of record type components. Other
9729 -- full type declarations are processed because they may have
9730 -- calls that must be checked. For example:
9732 -- type T is array (1 .. Some_Function_Call (...)) of Some_Type;
9734 -- ??? More work needed here to handle the following case:
9736 -- type Rec is record
9737 -- F : String (1 .. <some complicated expression>);
9740 when N_Full_Type_Declaration
=>
9741 if Is_Record_Type
(Defining_Entity
(Nod
)) then
9745 -- Skip calls placed in subprogram specifications since function
9746 -- calls initializing default parameter values will be processed
9747 -- when the call to the subprogram is found (if the default actual
9748 -- parameter is required), and calls found in aspects will be
9749 -- processed when their corresponding pragma is found, or in the
9750 -- specific case of class-wide pre-/postconditions, when their
9751 -- helpers are found.
9753 when N_Procedure_Specification
9754 | N_Function_Specification
9758 when N_Abstract_Subprogram_Declaration
9762 | N_Enumeration_Representation_Clause
9763 | N_Enumeration_Type_Definition
9764 | N_Function_Instantiation
9765 | N_Freeze_Generic_Entity
9766 | N_Generic_Function_Renaming_Declaration
9767 | N_Generic_Package_Renaming_Declaration
9768 | N_Generic_Procedure_Renaming_Declaration
9769 | N_Generic_Package_Declaration
9770 | N_Generic_Subprogram_Declaration
9772 | N_Number_Declaration
9773 | N_Package_Instantiation
9774 | N_Package_Renaming_Declaration
9776 | N_Procedure_Instantiation
9777 | N_Protected_Type_Declaration
9778 | N_Record_Representation_Clause
9779 | N_Validate_Unchecked_Conversion
9780 | N_Variable_Reference_Marker
9781 | N_Use_Package_Clause
9794 procedure Check_Calls
is new Traverse_Proc
(Process_Node
);
9796 -- Start of processing for Validate_Subprogram_Calls
9799 -- No action required if we are not generating code or compiling sources
9800 -- that have errors.
9802 if Serious_Errors_Detected
> 0
9803 or else Operating_Mode
/= Generate_Code
9809 end Validate_Subprogram_Calls
;
9815 procedure Warn_BIP
(Func_Call
: Node_Id
) is
9817 if Debug_Flag_Underscore_BB
then
9818 Error_Msg_N
("build-in-place function call??", Func_Call
);