1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2012, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree
; use Atree
;
27 with Checks
; use Checks
;
28 with Debug
; use Debug
;
29 with Einfo
; use Einfo
;
30 with Errout
; use Errout
;
31 with Elists
; use Elists
;
32 with Exp_Aggr
; use Exp_Aggr
;
33 with Exp_Atag
; use Exp_Atag
;
34 with Exp_Ch2
; use Exp_Ch2
;
35 with Exp_Ch3
; use Exp_Ch3
;
36 with Exp_Ch7
; use Exp_Ch7
;
37 with Exp_Ch9
; use Exp_Ch9
;
38 with Exp_Dbug
; use Exp_Dbug
;
39 with Exp_Disp
; use Exp_Disp
;
40 with Exp_Dist
; use Exp_Dist
;
41 with Exp_Intr
; use Exp_Intr
;
42 with Exp_Pakd
; use Exp_Pakd
;
43 with Exp_Tss
; use Exp_Tss
;
44 with Exp_Util
; use Exp_Util
;
45 with Exp_VFpt
; use Exp_VFpt
;
46 with Fname
; use Fname
;
47 with Freeze
; use Freeze
;
48 with Inline
; use Inline
;
50 with Namet
; use Namet
;
51 with Nlists
; use Nlists
;
52 with Nmake
; use Nmake
;
54 with Output
; use Output
;
55 with Restrict
; use Restrict
;
56 with Rident
; use Rident
;
57 with Rtsfind
; use Rtsfind
;
59 with Sem_Aux
; use Sem_Aux
;
60 with Sem_Ch6
; use Sem_Ch6
;
61 with Sem_Ch8
; use Sem_Ch8
;
62 with Sem_Ch12
; use Sem_Ch12
;
63 with Sem_Ch13
; use Sem_Ch13
;
64 with Sem_Dim
; use Sem_Dim
;
65 with Sem_Disp
; use Sem_Disp
;
66 with Sem_Dist
; use Sem_Dist
;
67 with Sem_Eval
; use Sem_Eval
;
68 with Sem_Mech
; use Sem_Mech
;
69 with Sem_Res
; use Sem_Res
;
70 with Sem_SCIL
; use Sem_SCIL
;
71 with Sem_Util
; use Sem_Util
;
72 with Sinfo
; use Sinfo
;
73 with Sinput
; use Sinput
;
74 with Snames
; use Snames
;
75 with Stand
; use Stand
;
76 with Targparm
; use Targparm
;
77 with Tbuild
; use Tbuild
;
78 with Uintp
; use Uintp
;
79 with Validsw
; use Validsw
;
81 package body Exp_Ch6
is
83 Inlined_Calls
: Elist_Id
:= No_Elist
;
84 Backend_Calls
: Elist_Id
:= No_Elist
;
85 -- List of frontend inlined calls and inline calls passed to the backend
87 -----------------------
88 -- Local Subprograms --
89 -----------------------
91 procedure Add_Access_Actual_To_Build_In_Place_Call
92 (Function_Call
: Node_Id
;
93 Function_Id
: Entity_Id
;
94 Return_Object
: Node_Id
;
95 Is_Access
: Boolean := False);
96 -- Ada 2005 (AI-318-02): Apply the Unrestricted_Access attribute to the
97 -- object name given by Return_Object and add the attribute to the end of
98 -- the actual parameter list associated with the build-in-place function
99 -- call denoted by Function_Call. However, if Is_Access is True, then
100 -- Return_Object is already an access expression, in which case it's passed
101 -- along directly to the build-in-place function. Finally, if Return_Object
102 -- is empty, then pass a null literal as the actual.
104 procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
105 (Function_Call
: Node_Id
;
106 Function_Id
: Entity_Id
;
107 Alloc_Form
: BIP_Allocation_Form
:= Unspecified
;
108 Alloc_Form_Exp
: Node_Id
:= Empty
;
109 Pool_Actual
: Node_Id
:= Make_Null
(No_Location
));
110 -- Ada 2005 (AI-318-02): Add the actuals needed for a build-in-place
111 -- function call that returns a caller-unknown-size result (BIP_Alloc_Form
112 -- and BIP_Storage_Pool). If Alloc_Form_Exp is present, then use it,
113 -- otherwise pass a literal corresponding to the Alloc_Form parameter
114 -- (which must not be Unspecified in that case). Pool_Actual is the
115 -- parameter to pass to BIP_Storage_Pool.
117 procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
118 (Func_Call
: Node_Id
;
120 Ptr_Typ
: Entity_Id
:= Empty
;
121 Master_Exp
: Node_Id
:= Empty
);
122 -- Ada 2005 (AI-318-02): If the result type of a build-in-place call needs
123 -- finalization actions, add an actual parameter which is a pointer to the
124 -- finalization master of the caller. If Master_Exp is not Empty, then that
125 -- will be passed as the actual. Otherwise, if Ptr_Typ is left Empty, this
126 -- will result in an automatic "null" value for the actual.
128 procedure Add_Task_Actuals_To_Build_In_Place_Call
129 (Function_Call
: Node_Id
;
130 Function_Id
: Entity_Id
;
131 Master_Actual
: Node_Id
);
132 -- Ada 2005 (AI-318-02): For a build-in-place call, if the result type
133 -- contains tasks, add two actual parameters: the master, and a pointer to
134 -- the caller's activation chain. Master_Actual is the actual parameter
135 -- expression to pass for the master. In most cases, this is the current
136 -- master (_master). The two exceptions are: If the function call is the
137 -- initialization expression for an allocator, we pass the master of the
138 -- access type. If the function call is the initialization expression for a
139 -- return object, we pass along the master passed in by the caller. The
140 -- activation chain to pass is always the local one. Note: Master_Actual
141 -- can be Empty, but only if there are no tasks.
143 procedure Check_Overriding_Operation
(Subp
: Entity_Id
);
144 -- Subp is a dispatching operation. Check whether it may override an
145 -- inherited private operation, in which case its DT entry is that of
146 -- the hidden operation, not the one it may have received earlier.
147 -- This must be done before emitting the code to set the corresponding
148 -- DT to the address of the subprogram. The actual placement of Subp in
149 -- the proper place in the list of primitive operations is done in
150 -- Declare_Inherited_Private_Subprograms, which also has to deal with
151 -- implicit operations. This duplication is unavoidable for now???
153 procedure Detect_Infinite_Recursion
(N
: Node_Id
; Spec
: Entity_Id
);
154 -- This procedure is called only if the subprogram body N, whose spec
155 -- has the given entity Spec, contains a parameterless recursive call.
156 -- It attempts to generate runtime code to detect if this a case of
157 -- infinite recursion.
159 -- The body is scanned to determine dependencies. If the only external
160 -- dependencies are on a small set of scalar variables, then the values
161 -- of these variables are captured on entry to the subprogram, and if
162 -- the values are not changed for the call, we know immediately that
163 -- we have an infinite recursion.
165 procedure Expand_Ctrl_Function_Call
(N
: Node_Id
);
166 -- N is a function call which returns a controlled object. Transform the
167 -- call into a temporary which retrieves the returned object from the
168 -- secondary stack using 'reference.
170 procedure Expand_Inlined_Call
173 Orig_Subp
: Entity_Id
);
174 -- If called subprogram can be inlined by the front-end, retrieve the
175 -- analyzed body, replace formals with actuals and expand call in place.
176 -- Generate thunks for actuals that are expressions, and insert the
177 -- corresponding constant declarations before the call. If the original
178 -- call is to a derived operation, the return type is the one of the
179 -- derived operation, but the body is that of the original, so return
180 -- expressions in the body must be converted to the desired type (which
181 -- is simply not noted in the tree without inline expansion).
183 procedure Expand_Non_Function_Return
(N
: Node_Id
);
184 -- Called by Expand_N_Simple_Return_Statement in case we're returning from
185 -- a procedure body, entry body, accept statement, or extended return
186 -- statement. Note that all non-function returns are simple return
189 function Expand_Protected_Object_Reference
191 Scop
: Entity_Id
) return Node_Id
;
193 procedure Expand_Protected_Subprogram_Call
197 -- A call to a protected subprogram within the protected object may appear
198 -- as a regular call. The list of actuals must be expanded to contain a
199 -- reference to the object itself, and the call becomes a call to the
200 -- corresponding protected subprogram.
202 function Has_Unconstrained_Access_Discriminants
203 (Subtyp
: Entity_Id
) return Boolean;
204 -- Returns True if the given subtype is unconstrained and has one
205 -- or more access discriminants.
207 procedure Expand_Simple_Function_Return
(N
: Node_Id
);
208 -- Expand simple return from function. In the case where we are returning
209 -- from a function body this is called by Expand_N_Simple_Return_Statement.
211 ----------------------------------------------
212 -- Add_Access_Actual_To_Build_In_Place_Call --
213 ----------------------------------------------
215 procedure Add_Access_Actual_To_Build_In_Place_Call
216 (Function_Call
: Node_Id
;
217 Function_Id
: Entity_Id
;
218 Return_Object
: Node_Id
;
219 Is_Access
: Boolean := False)
221 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
222 Obj_Address
: Node_Id
;
223 Obj_Acc_Formal
: Entity_Id
;
226 -- Locate the implicit access parameter in the called function
228 Obj_Acc_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Object_Access
);
230 -- If no return object is provided, then pass null
232 if not Present
(Return_Object
) then
233 Obj_Address
:= Make_Null
(Loc
);
234 Set_Parent
(Obj_Address
, Function_Call
);
236 -- If Return_Object is already an expression of an access type, then use
237 -- it directly, since it must be an access value denoting the return
238 -- object, and couldn't possibly be the return object itself.
241 Obj_Address
:= Return_Object
;
242 Set_Parent
(Obj_Address
, Function_Call
);
244 -- Apply Unrestricted_Access to caller's return object
248 Make_Attribute_Reference
(Loc
,
249 Prefix
=> Return_Object
,
250 Attribute_Name
=> Name_Unrestricted_Access
);
252 Set_Parent
(Return_Object
, Obj_Address
);
253 Set_Parent
(Obj_Address
, Function_Call
);
256 Analyze_And_Resolve
(Obj_Address
, Etype
(Obj_Acc_Formal
));
258 -- Build the parameter association for the new actual and add it to the
259 -- end of the function's actuals.
261 Add_Extra_Actual_To_Call
(Function_Call
, Obj_Acc_Formal
, Obj_Address
);
262 end Add_Access_Actual_To_Build_In_Place_Call
;
264 ------------------------------------------------------
265 -- Add_Unconstrained_Actuals_To_Build_In_Place_Call --
266 ------------------------------------------------------
268 procedure Add_Unconstrained_Actuals_To_Build_In_Place_Call
269 (Function_Call
: Node_Id
;
270 Function_Id
: Entity_Id
;
271 Alloc_Form
: BIP_Allocation_Form
:= Unspecified
;
272 Alloc_Form_Exp
: Node_Id
:= Empty
;
273 Pool_Actual
: Node_Id
:= Make_Null
(No_Location
))
275 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
276 Alloc_Form_Actual
: Node_Id
;
277 Alloc_Form_Formal
: Node_Id
;
278 Pool_Formal
: Node_Id
;
281 -- The allocation form generally doesn't need to be passed in the case
282 -- of a constrained result subtype, since normally the caller performs
283 -- the allocation in that case. However this formal is still needed in
284 -- the case where the function has a tagged result, because generally
285 -- such functions can be called in a dispatching context and such calls
286 -- must be handled like calls to class-wide functions.
288 if Is_Constrained
(Underlying_Type
(Etype
(Function_Id
)))
289 and then not Is_Tagged_Type
(Underlying_Type
(Etype
(Function_Id
)))
294 -- Locate the implicit allocation form parameter in the called function.
295 -- Maybe it would be better for each implicit formal of a build-in-place
296 -- function to have a flag or a Uint attribute to identify it. ???
298 Alloc_Form_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Alloc_Form
);
300 if Present
(Alloc_Form_Exp
) then
301 pragma Assert
(Alloc_Form
= Unspecified
);
303 Alloc_Form_Actual
:= Alloc_Form_Exp
;
306 pragma Assert
(Alloc_Form
/= Unspecified
);
309 Make_Integer_Literal
(Loc
,
310 Intval
=> UI_From_Int
(BIP_Allocation_Form
'Pos (Alloc_Form
)));
313 Analyze_And_Resolve
(Alloc_Form_Actual
, Etype
(Alloc_Form_Formal
));
315 -- Build the parameter association for the new actual and add it to the
316 -- end of the function's actuals.
318 Add_Extra_Actual_To_Call
319 (Function_Call
, Alloc_Form_Formal
, Alloc_Form_Actual
);
321 -- Pass the Storage_Pool parameter. This parameter is omitted on
322 -- .NET/JVM/ZFP as those targets do not support pools.
325 and then RTE_Available
(RE_Root_Storage_Pool_Ptr
)
327 Pool_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Storage_Pool
);
328 Analyze_And_Resolve
(Pool_Actual
, Etype
(Pool_Formal
));
329 Add_Extra_Actual_To_Call
330 (Function_Call
, Pool_Formal
, Pool_Actual
);
332 end Add_Unconstrained_Actuals_To_Build_In_Place_Call
;
334 -----------------------------------------------------------
335 -- Add_Finalization_Master_Actual_To_Build_In_Place_Call --
336 -----------------------------------------------------------
338 procedure Add_Finalization_Master_Actual_To_Build_In_Place_Call
339 (Func_Call
: Node_Id
;
341 Ptr_Typ
: Entity_Id
:= Empty
;
342 Master_Exp
: Node_Id
:= Empty
)
345 if not Needs_BIP_Finalization_Master
(Func_Id
) then
350 Formal
: constant Entity_Id
:=
351 Build_In_Place_Formal
(Func_Id
, BIP_Finalization_Master
);
352 Loc
: constant Source_Ptr
:= Sloc
(Func_Call
);
355 Desig_Typ
: Entity_Id
;
358 -- If there is a finalization master actual, such as the implicit
359 -- finalization master of an enclosing build-in-place function,
360 -- then this must be added as an extra actual of the call.
362 if Present
(Master_Exp
) then
363 Actual
:= Master_Exp
;
365 -- Case where the context does not require an actual master
367 elsif No
(Ptr_Typ
) then
368 Actual
:= Make_Null
(Loc
);
371 Desig_Typ
:= Directly_Designated_Type
(Ptr_Typ
);
373 -- Check for a library-level access type whose designated type has
374 -- supressed finalization. Such an access types lack a master.
375 -- Pass a null actual to the callee in order to signal a missing
378 if Is_Library_Level_Entity
(Ptr_Typ
)
379 and then Finalize_Storage_Only
(Desig_Typ
)
381 Actual
:= Make_Null
(Loc
);
383 -- Types in need of finalization actions
385 elsif Needs_Finalization
(Desig_Typ
) then
387 -- The general mechanism of creating finalization masters for
388 -- anonymous access types is disabled by default, otherwise
389 -- finalization masters will pop all over the place. Such types
390 -- use context-specific masters.
392 if Ekind
(Ptr_Typ
) = E_Anonymous_Access_Type
393 and then No
(Finalization_Master
(Ptr_Typ
))
395 Build_Finalization_Master
397 Ins_Node
=> Associated_Node_For_Itype
(Ptr_Typ
),
398 Encl_Scope
=> Scope
(Ptr_Typ
));
401 -- Access-to-controlled types should always have a master
403 pragma Assert
(Present
(Finalization_Master
(Ptr_Typ
)));
406 Make_Attribute_Reference
(Loc
,
408 New_Reference_To
(Finalization_Master
(Ptr_Typ
), Loc
),
409 Attribute_Name
=> Name_Unrestricted_Access
);
414 Actual
:= Make_Null
(Loc
);
418 Analyze_And_Resolve
(Actual
, Etype
(Formal
));
420 -- Build the parameter association for the new actual and add it to
421 -- the end of the function's actuals.
423 Add_Extra_Actual_To_Call
(Func_Call
, Formal
, Actual
);
425 end Add_Finalization_Master_Actual_To_Build_In_Place_Call
;
427 ------------------------------
428 -- Add_Extra_Actual_To_Call --
429 ------------------------------
431 procedure Add_Extra_Actual_To_Call
432 (Subprogram_Call
: Node_Id
;
433 Extra_Formal
: Entity_Id
;
434 Extra_Actual
: Node_Id
)
436 Loc
: constant Source_Ptr
:= Sloc
(Subprogram_Call
);
437 Param_Assoc
: Node_Id
;
441 Make_Parameter_Association
(Loc
,
442 Selector_Name
=> New_Occurrence_Of
(Extra_Formal
, Loc
),
443 Explicit_Actual_Parameter
=> Extra_Actual
);
445 Set_Parent
(Param_Assoc
, Subprogram_Call
);
446 Set_Parent
(Extra_Actual
, Param_Assoc
);
448 if Present
(Parameter_Associations
(Subprogram_Call
)) then
449 if Nkind
(Last
(Parameter_Associations
(Subprogram_Call
))) =
450 N_Parameter_Association
453 -- Find last named actual, and append
458 L
:= First_Actual
(Subprogram_Call
);
459 while Present
(L
) loop
460 if No
(Next_Actual
(L
)) then
461 Set_Next_Named_Actual
(Parent
(L
), Extra_Actual
);
469 Set_First_Named_Actual
(Subprogram_Call
, Extra_Actual
);
472 Append
(Param_Assoc
, To
=> Parameter_Associations
(Subprogram_Call
));
475 Set_Parameter_Associations
(Subprogram_Call
, New_List
(Param_Assoc
));
476 Set_First_Named_Actual
(Subprogram_Call
, Extra_Actual
);
478 end Add_Extra_Actual_To_Call
;
480 ---------------------------------------------
481 -- Add_Task_Actuals_To_Build_In_Place_Call --
482 ---------------------------------------------
484 procedure Add_Task_Actuals_To_Build_In_Place_Call
485 (Function_Call
: Node_Id
;
486 Function_Id
: Entity_Id
;
487 Master_Actual
: Node_Id
)
489 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
490 Result_Subt
: constant Entity_Id
:=
491 Available_View
(Etype
(Function_Id
));
493 Chain_Actual
: Node_Id
;
494 Chain_Formal
: Node_Id
;
495 Master_Formal
: Node_Id
;
498 -- No such extra parameters are needed if there are no tasks
500 if not Has_Task
(Result_Subt
) then
504 Actual
:= Master_Actual
;
506 -- Use a dummy _master actual in case of No_Task_Hierarchy
508 if Restriction_Active
(No_Task_Hierarchy
) then
509 Actual
:= New_Occurrence_Of
(RTE
(RE_Library_Task_Level
), Loc
);
511 -- In the case where we use the master associated with an access type,
512 -- the actual is an entity and requires an explicit reference.
514 elsif Nkind
(Actual
) = N_Defining_Identifier
then
515 Actual
:= New_Reference_To
(Actual
, Loc
);
518 -- Locate the implicit master parameter in the called function
520 Master_Formal
:= Build_In_Place_Formal
(Function_Id
, BIP_Task_Master
);
521 Analyze_And_Resolve
(Actual
, Etype
(Master_Formal
));
523 -- Build the parameter association for the new actual and add it to the
524 -- end of the function's actuals.
526 Add_Extra_Actual_To_Call
(Function_Call
, Master_Formal
, Actual
);
528 -- Locate the implicit activation chain parameter in the called function
531 Build_In_Place_Formal
(Function_Id
, BIP_Activation_Chain
);
533 -- Create the actual which is a pointer to the current activation chain
536 Make_Attribute_Reference
(Loc
,
537 Prefix
=> Make_Identifier
(Loc
, Name_uChain
),
538 Attribute_Name
=> Name_Unrestricted_Access
);
540 Analyze_And_Resolve
(Chain_Actual
, Etype
(Chain_Formal
));
542 -- Build the parameter association for the new actual and add it to the
543 -- end of the function's actuals.
545 Add_Extra_Actual_To_Call
(Function_Call
, Chain_Formal
, Chain_Actual
);
546 end Add_Task_Actuals_To_Build_In_Place_Call
;
548 -----------------------
549 -- BIP_Formal_Suffix --
550 -----------------------
552 function BIP_Formal_Suffix
(Kind
: BIP_Formal_Kind
) return String is
555 when BIP_Alloc_Form
=>
557 when BIP_Storage_Pool
=>
558 return "BIPstoragepool";
559 when BIP_Finalization_Master
=>
560 return "BIPfinalizationmaster";
561 when BIP_Task_Master
=>
562 return "BIPtaskmaster";
563 when BIP_Activation_Chain
=>
564 return "BIPactivationchain";
565 when BIP_Object_Access
=>
568 end BIP_Formal_Suffix
;
570 ---------------------------
571 -- Build_In_Place_Formal --
572 ---------------------------
574 function Build_In_Place_Formal
576 Kind
: BIP_Formal_Kind
) return Entity_Id
578 Formal_Name
: constant Name_Id
:=
580 (Chars
(Func
), BIP_Formal_Suffix
(Kind
));
581 Extra_Formal
: Entity_Id
:= Extra_Formals
(Func
);
584 -- Maybe it would be better for each implicit formal of a build-in-place
585 -- function to have a flag or a Uint attribute to identify it. ???
587 -- The return type in the function declaration may have been a limited
588 -- view, and the extra formals for the function were not generated at
589 -- that point. At the point of call the full view must be available and
590 -- the extra formals can be created.
592 if No
(Extra_Formal
) then
593 Create_Extra_Formals
(Func
);
594 Extra_Formal
:= Extra_Formals
(Func
);
598 pragma Assert
(Present
(Extra_Formal
));
599 exit when Chars
(Extra_Formal
) = Formal_Name
;
601 Next_Formal_With_Extras
(Extra_Formal
);
605 end Build_In_Place_Formal
;
607 --------------------------------
608 -- Check_Overriding_Operation --
609 --------------------------------
611 procedure Check_Overriding_Operation
(Subp
: Entity_Id
) is
612 Typ
: constant Entity_Id
:= Find_Dispatching_Type
(Subp
);
613 Op_List
: constant Elist_Id
:= Primitive_Operations
(Typ
);
619 if Is_Derived_Type
(Typ
)
620 and then not Is_Private_Type
(Typ
)
621 and then In_Open_Scopes
(Scope
(Etype
(Typ
)))
622 and then Is_Base_Type
(Typ
)
624 -- Subp overrides an inherited private operation if there is an
625 -- inherited operation with a different name than Subp (see
626 -- Derive_Subprogram) whose Alias is a hidden subprogram with the
627 -- same name as Subp.
629 Op_Elmt
:= First_Elmt
(Op_List
);
630 while Present
(Op_Elmt
) loop
631 Prim_Op
:= Node
(Op_Elmt
);
632 Par_Op
:= Alias
(Prim_Op
);
635 and then not Comes_From_Source
(Prim_Op
)
636 and then Chars
(Prim_Op
) /= Chars
(Par_Op
)
637 and then Chars
(Par_Op
) = Chars
(Subp
)
638 and then Is_Hidden
(Par_Op
)
639 and then Type_Conformant
(Prim_Op
, Subp
)
641 Set_DT_Position
(Subp
, DT_Position
(Prim_Op
));
647 end Check_Overriding_Operation
;
649 -------------------------------
650 -- Detect_Infinite_Recursion --
651 -------------------------------
653 procedure Detect_Infinite_Recursion
(N
: Node_Id
; Spec
: Entity_Id
) is
654 Loc
: constant Source_Ptr
:= Sloc
(N
);
656 Var_List
: constant Elist_Id
:= New_Elmt_List
;
657 -- List of globals referenced by body of procedure
659 Call_List
: constant Elist_Id
:= New_Elmt_List
;
660 -- List of recursive calls in body of procedure
662 Shad_List
: constant Elist_Id
:= New_Elmt_List
;
663 -- List of entity id's for entities created to capture the value of
664 -- referenced globals on entry to the procedure.
666 Scop
: constant Uint
:= Scope_Depth
(Spec
);
667 -- This is used to record the scope depth of the current procedure, so
668 -- that we can identify global references.
670 Max_Vars
: constant := 4;
671 -- Do not test more than four global variables
673 Count_Vars
: Natural := 0;
674 -- Count variables found so far
686 function Process
(Nod
: Node_Id
) return Traverse_Result
;
687 -- Function to traverse the subprogram body (using Traverse_Func)
693 function Process
(Nod
: Node_Id
) return Traverse_Result
is
697 if Nkind
(Nod
) = N_Procedure_Call_Statement
then
699 -- Case of one of the detected recursive calls
701 if Is_Entity_Name
(Name
(Nod
))
702 and then Has_Recursive_Call
(Entity
(Name
(Nod
)))
703 and then Entity
(Name
(Nod
)) = Spec
705 Append_Elmt
(Nod
, Call_List
);
708 -- Any other procedure call may have side effects
714 -- A call to a pure function can always be ignored
716 elsif Nkind
(Nod
) = N_Function_Call
717 and then Is_Entity_Name
(Name
(Nod
))
718 and then Is_Pure
(Entity
(Name
(Nod
)))
722 -- Case of an identifier reference
724 elsif Nkind
(Nod
) = N_Identifier
then
727 -- If no entity, then ignore the reference
729 -- Not clear why this can happen. To investigate, remove this
730 -- test and look at the crash that occurs here in 3401-004 ???
735 -- Ignore entities with no Scope, again not clear how this
736 -- can happen, to investigate, look at 4108-008 ???
738 elsif No
(Scope
(Ent
)) then
741 -- Ignore the reference if not to a more global object
743 elsif Scope_Depth
(Scope
(Ent
)) >= Scop
then
746 -- References to types, exceptions and constants are always OK
749 or else Ekind
(Ent
) = E_Exception
750 or else Ekind
(Ent
) = E_Constant
754 -- If other than a non-volatile scalar variable, we have some
755 -- kind of global reference (e.g. to a function) that we cannot
756 -- deal with so we forget the attempt.
758 elsif Ekind
(Ent
) /= E_Variable
759 or else not Is_Scalar_Type
(Etype
(Ent
))
760 or else Treat_As_Volatile
(Ent
)
764 -- Otherwise we have a reference to a global scalar
767 -- Loop through global entities already detected
769 Elm
:= First_Elmt
(Var_List
);
771 -- If not detected before, record this new global reference
774 Count_Vars
:= Count_Vars
+ 1;
776 if Count_Vars
<= Max_Vars
then
777 Append_Elmt
(Entity
(Nod
), Var_List
);
784 -- If recorded before, ignore
786 elsif Node
(Elm
) = Entity
(Nod
) then
789 -- Otherwise keep looking
799 -- For all other node kinds, recursively visit syntactic children
806 function Traverse_Body
is new Traverse_Func
(Process
);
808 -- Start of processing for Detect_Infinite_Recursion
811 -- Do not attempt detection in No_Implicit_Conditional mode, since we
812 -- won't be able to generate the code to handle the recursion in any
815 if Restriction_Active
(No_Implicit_Conditionals
) then
819 -- Otherwise do traversal and quit if we get abandon signal
821 if Traverse_Body
(N
) = Abandon
then
824 -- We must have a call, since Has_Recursive_Call was set. If not just
825 -- ignore (this is only an error check, so if we have a funny situation,
826 -- due to bugs or errors, we do not want to bomb!)
828 elsif Is_Empty_Elmt_List
(Call_List
) then
832 -- Here is the case where we detect recursion at compile time
834 -- Push our current scope for analyzing the declarations and code that
835 -- we will insert for the checking.
839 -- This loop builds temporary variables for each of the referenced
840 -- globals, so that at the end of the loop the list Shad_List contains
841 -- these temporaries in one-to-one correspondence with the elements in
845 Elm
:= First_Elmt
(Var_List
);
846 while Present
(Elm
) loop
848 Ent
:= Make_Temporary
(Loc
, 'S');
849 Append_Elmt
(Ent
, Shad_List
);
851 -- Insert a declaration for this temporary at the start of the
852 -- declarations for the procedure. The temporaries are declared as
853 -- constant objects initialized to the current values of the
854 -- corresponding temporaries.
857 Make_Object_Declaration
(Loc
,
858 Defining_Identifier
=> Ent
,
859 Object_Definition
=> New_Occurrence_Of
(Etype
(Var
), Loc
),
860 Constant_Present
=> True,
861 Expression
=> New_Occurrence_Of
(Var
, Loc
));
864 Prepend
(Decl
, Declarations
(N
));
866 Insert_After
(Last
, Decl
);
874 -- Loop through calls
876 Call
:= First_Elmt
(Call_List
);
877 while Present
(Call
) loop
879 -- Build a predicate expression of the form
882 -- and then global1 = temp1
883 -- and then global2 = temp2
886 -- This predicate determines if any of the global values
887 -- referenced by the procedure have changed since the
888 -- current call, if not an infinite recursion is assured.
890 Test
:= New_Occurrence_Of
(Standard_True
, Loc
);
892 Elm1
:= First_Elmt
(Var_List
);
893 Elm2
:= First_Elmt
(Shad_List
);
894 while Present
(Elm1
) loop
900 Left_Opnd
=> New_Occurrence_Of
(Node
(Elm1
), Loc
),
901 Right_Opnd
=> New_Occurrence_Of
(Node
(Elm2
), Loc
)));
907 -- Now we replace the call with the sequence
909 -- if no-changes (see above) then
910 -- raise Storage_Error;
915 Rewrite
(Node
(Call
),
916 Make_If_Statement
(Loc
,
918 Then_Statements
=> New_List
(
919 Make_Raise_Storage_Error
(Loc
,
920 Reason
=> SE_Infinite_Recursion
)),
922 Else_Statements
=> New_List
(
923 Relocate_Node
(Node
(Call
)))));
925 Analyze
(Node
(Call
));
930 -- Remove temporary scope stack entry used for analysis
933 end Detect_Infinite_Recursion
;
939 procedure Expand_Actuals
(N
: Node_Id
; Subp
: Entity_Id
) is
940 Loc
: constant Source_Ptr
:= Sloc
(N
);
945 E_Formal
: Entity_Id
;
947 procedure Add_Call_By_Copy_Code
;
948 -- For cases where the parameter must be passed by copy, this routine
949 -- generates a temporary variable into which the actual is copied and
950 -- then passes this as the parameter. For an OUT or IN OUT parameter,
951 -- an assignment is also generated to copy the result back. The call
952 -- also takes care of any constraint checks required for the type
953 -- conversion case (on both the way in and the way out).
955 procedure Add_Simple_Call_By_Copy_Code
;
956 -- This is similar to the above, but is used in cases where we know
957 -- that all that is needed is to simply create a temporary and copy
958 -- the value in and out of the temporary.
960 procedure Check_Fortran_Logical
;
961 -- A value of type Logical that is passed through a formal parameter
962 -- must be normalized because .TRUE. usually does not have the same
963 -- representation as True. We assume that .FALSE. = False = 0.
964 -- What about functions that return a logical type ???
966 function Is_Legal_Copy
return Boolean;
967 -- Check that an actual can be copied before generating the temporary
968 -- to be used in the call. If the actual is of a by_reference type then
969 -- the program is illegal (this can only happen in the presence of
970 -- rep. clauses that force an incorrect alignment). If the formal is
971 -- a by_reference parameter imposed by a DEC pragma, emit a warning to
972 -- the effect that this might lead to unaligned arguments.
974 function Make_Var
(Actual
: Node_Id
) return Entity_Id
;
975 -- Returns an entity that refers to the given actual parameter,
976 -- Actual (not including any type conversion). If Actual is an
977 -- entity name, then this entity is returned unchanged, otherwise
978 -- a renaming is created to provide an entity for the actual.
980 procedure Reset_Packed_Prefix
;
981 -- The expansion of a packed array component reference is delayed in
982 -- the context of a call. Now we need to complete the expansion, so we
983 -- unmark the analyzed bits in all prefixes.
985 ---------------------------
986 -- Add_Call_By_Copy_Code --
987 ---------------------------
989 procedure Add_Call_By_Copy_Code
is
995 F_Typ
: constant Entity_Id
:= Etype
(Formal
);
1000 if not Is_Legal_Copy
then
1004 Temp
:= Make_Temporary
(Loc
, 'T', Actual
);
1006 -- Use formal type for temp, unless formal type is an unconstrained
1007 -- array, in which case we don't have to worry about bounds checks,
1008 -- and we use the actual type, since that has appropriate bounds.
1010 if Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
) then
1011 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1013 Indic
:= New_Occurrence_Of
(Etype
(Formal
), Loc
);
1016 if Nkind
(Actual
) = N_Type_Conversion
then
1017 V_Typ
:= Etype
(Expression
(Actual
));
1019 -- If the formal is an (in-)out parameter, capture the name
1020 -- of the variable in order to build the post-call assignment.
1022 Var
:= Make_Var
(Expression
(Actual
));
1024 Crep
:= not Same_Representation
1025 (F_Typ
, Etype
(Expression
(Actual
)));
1028 V_Typ
:= Etype
(Actual
);
1029 Var
:= Make_Var
(Actual
);
1033 -- Setup initialization for case of in out parameter, or an out
1034 -- parameter where the formal is an unconstrained array (in the
1035 -- latter case, we have to pass in an object with bounds).
1037 -- If this is an out parameter, the initial copy is wasteful, so as
1038 -- an optimization for the one-dimensional case we extract the
1039 -- bounds of the actual and build an uninitialized temporary of the
1042 if Ekind
(Formal
) = E_In_Out_Parameter
1043 or else (Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
))
1045 if Nkind
(Actual
) = N_Type_Conversion
then
1046 if Conversion_OK
(Actual
) then
1047 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1049 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1052 elsif Ekind
(Formal
) = E_Out_Parameter
1053 and then Is_Array_Type
(F_Typ
)
1054 and then Number_Dimensions
(F_Typ
) = 1
1055 and then not Has_Non_Null_Base_Init_Proc
(F_Typ
)
1057 -- Actual is a one-dimensional array or slice, and the type
1058 -- requires no initialization. Create a temporary of the
1059 -- right size, but do not copy actual into it (optimization).
1063 Make_Subtype_Indication
(Loc
,
1065 New_Occurrence_Of
(F_Typ
, Loc
),
1067 Make_Index_Or_Discriminant_Constraint
(Loc
,
1068 Constraints
=> New_List
(
1071 Make_Attribute_Reference
(Loc
,
1072 Prefix
=> New_Occurrence_Of
(Var
, Loc
),
1073 Attribute_Name
=> Name_First
),
1075 Make_Attribute_Reference
(Loc
,
1076 Prefix
=> New_Occurrence_Of
(Var
, Loc
),
1077 Attribute_Name
=> Name_Last
)))));
1080 Init
:= New_Occurrence_Of
(Var
, Loc
);
1083 -- An initialization is created for packed conversions as
1084 -- actuals for out parameters to enable Make_Object_Declaration
1085 -- to determine the proper subtype for N_Node. Note that this
1086 -- is wasteful because the extra copying on the call side is
1087 -- not required for such out parameters. ???
1089 elsif Ekind
(Formal
) = E_Out_Parameter
1090 and then Nkind
(Actual
) = N_Type_Conversion
1091 and then (Is_Bit_Packed_Array
(F_Typ
)
1093 Is_Bit_Packed_Array
(Etype
(Expression
(Actual
))))
1095 if Conversion_OK
(Actual
) then
1096 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1098 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1101 elsif Ekind
(Formal
) = E_In_Parameter
then
1103 -- Handle the case in which the actual is a type conversion
1105 if Nkind
(Actual
) = N_Type_Conversion
then
1106 if Conversion_OK
(Actual
) then
1107 Init
:= OK_Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1109 Init
:= Convert_To
(F_Typ
, New_Occurrence_Of
(Var
, Loc
));
1112 Init
:= New_Occurrence_Of
(Var
, Loc
);
1120 Make_Object_Declaration
(Loc
,
1121 Defining_Identifier
=> Temp
,
1122 Object_Definition
=> Indic
,
1123 Expression
=> Init
);
1124 Set_Assignment_OK
(N_Node
);
1125 Insert_Action
(N
, N_Node
);
1127 -- Now, normally the deal here is that we use the defining
1128 -- identifier created by that object declaration. There is
1129 -- one exception to this. In the change of representation case
1130 -- the above declaration will end up looking like:
1132 -- temp : type := identifier;
1134 -- And in this case we might as well use the identifier directly
1135 -- and eliminate the temporary. Note that the analysis of the
1136 -- declaration was not a waste of time in that case, since it is
1137 -- what generated the necessary change of representation code. If
1138 -- the change of representation introduced additional code, as in
1139 -- a fixed-integer conversion, the expression is not an identifier
1140 -- and must be kept.
1143 and then Present
(Expression
(N_Node
))
1144 and then Is_Entity_Name
(Expression
(N_Node
))
1146 Temp
:= Entity
(Expression
(N_Node
));
1147 Rewrite
(N_Node
, Make_Null_Statement
(Loc
));
1150 -- For IN parameter, all we do is to replace the actual
1152 if Ekind
(Formal
) = E_In_Parameter
then
1153 Rewrite
(Actual
, New_Reference_To
(Temp
, Loc
));
1156 -- Processing for OUT or IN OUT parameter
1159 -- Kill current value indications for the temporary variable we
1160 -- created, since we just passed it as an OUT parameter.
1162 Kill_Current_Values
(Temp
);
1163 Set_Is_Known_Valid
(Temp
, False);
1165 -- If type conversion, use reverse conversion on exit
1167 if Nkind
(Actual
) = N_Type_Conversion
then
1168 if Conversion_OK
(Actual
) then
1169 Expr
:= OK_Convert_To
(V_Typ
, New_Occurrence_Of
(Temp
, Loc
));
1171 Expr
:= Convert_To
(V_Typ
, New_Occurrence_Of
(Temp
, Loc
));
1174 Expr
:= New_Occurrence_Of
(Temp
, Loc
);
1177 Rewrite
(Actual
, New_Reference_To
(Temp
, Loc
));
1180 -- If the actual is a conversion of a packed reference, it may
1181 -- already have been expanded by Remove_Side_Effects, and the
1182 -- resulting variable is a temporary which does not designate
1183 -- the proper out-parameter, which may not be addressable. In
1184 -- that case, generate an assignment to the original expression
1185 -- (before expansion of the packed reference) so that the proper
1186 -- expansion of assignment to a packed component can take place.
1193 if Is_Renaming_Of_Object
(Var
)
1194 and then Nkind
(Renamed_Object
(Var
)) = N_Selected_Component
1195 and then Is_Entity_Name
(Prefix
(Renamed_Object
(Var
)))
1196 and then Nkind
(Original_Node
(Prefix
(Renamed_Object
(Var
))))
1197 = N_Indexed_Component
1199 Has_Non_Standard_Rep
(Etype
(Prefix
(Renamed_Object
(Var
))))
1201 Obj
:= Renamed_Object
(Var
);
1203 Make_Selected_Component
(Loc
,
1205 New_Copy_Tree
(Original_Node
(Prefix
(Obj
))),
1206 Selector_Name
=> New_Copy
(Selector_Name
(Obj
)));
1207 Reset_Analyzed_Flags
(Lhs
);
1210 Lhs
:= New_Occurrence_Of
(Var
, Loc
);
1213 Set_Assignment_OK
(Lhs
);
1215 if Is_Access_Type
(E_Formal
)
1216 and then Is_Entity_Name
(Lhs
)
1218 Present
(Effective_Extra_Accessibility
(Entity
(Lhs
)))
1220 -- Copyback target is an Ada 2012 stand-alone object of an
1221 -- anonymous access type.
1223 pragma Assert
(Ada_Version
>= Ada_2012
);
1225 if Type_Access_Level
(E_Formal
) >
1226 Object_Access_Level
(Lhs
)
1228 Append_To
(Post_Call
,
1229 Make_Raise_Program_Error
(Loc
,
1230 Reason
=> PE_Accessibility_Check_Failed
));
1233 Append_To
(Post_Call
,
1234 Make_Assignment_Statement
(Loc
,
1236 Expression
=> Expr
));
1238 -- We would like to somehow suppress generation of the
1239 -- extra_accessibility assignment generated by the expansion
1240 -- of the above assignment statement. It's not a correctness
1241 -- issue because the following assignment renders it dead,
1242 -- but generating back-to-back assignments to the same
1243 -- target is undesirable. ???
1245 Append_To
(Post_Call
,
1246 Make_Assignment_Statement
(Loc
,
1247 Name
=> New_Occurrence_Of
(
1248 Effective_Extra_Accessibility
(Entity
(Lhs
)), Loc
),
1249 Expression
=> Make_Integer_Literal
(Loc
,
1250 Type_Access_Level
(E_Formal
))));
1253 Append_To
(Post_Call
,
1254 Make_Assignment_Statement
(Loc
,
1256 Expression
=> Expr
));
1260 end Add_Call_By_Copy_Code
;
1262 ----------------------------------
1263 -- Add_Simple_Call_By_Copy_Code --
1264 ----------------------------------
1266 procedure Add_Simple_Call_By_Copy_Code
is
1274 F_Typ
: constant Entity_Id
:= Etype
(Formal
);
1277 if not Is_Legal_Copy
then
1281 -- Use formal type for temp, unless formal type is an unconstrained
1282 -- array, in which case we don't have to worry about bounds checks,
1283 -- and we use the actual type, since that has appropriate bounds.
1285 if Is_Array_Type
(F_Typ
) and then not Is_Constrained
(F_Typ
) then
1286 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1288 Indic
:= New_Occurrence_Of
(Etype
(Formal
), Loc
);
1291 -- Prepare to generate code
1293 Reset_Packed_Prefix
;
1295 Temp
:= Make_Temporary
(Loc
, 'T', Actual
);
1296 Incod
:= Relocate_Node
(Actual
);
1297 Outcod
:= New_Copy_Tree
(Incod
);
1299 -- Generate declaration of temporary variable, initializing it
1300 -- with the input parameter unless we have an OUT formal or
1301 -- this is an initialization call.
1303 -- If the formal is an out parameter with discriminants, the
1304 -- discriminants must be captured even if the rest of the object
1305 -- is in principle uninitialized, because the discriminants may
1306 -- be read by the called subprogram.
1308 if Ekind
(Formal
) = E_Out_Parameter
then
1311 if Has_Discriminants
(Etype
(Formal
)) then
1312 Indic
:= New_Occurrence_Of
(Etype
(Actual
), Loc
);
1315 elsif Inside_Init_Proc
then
1317 -- Could use a comment here to match comment below ???
1319 if Nkind
(Actual
) /= N_Selected_Component
1321 not Has_Discriminant_Dependent_Constraint
1322 (Entity
(Selector_Name
(Actual
)))
1326 -- Otherwise, keep the component in order to generate the proper
1327 -- actual subtype, that depends on enclosing discriminants.
1335 Make_Object_Declaration
(Loc
,
1336 Defining_Identifier
=> Temp
,
1337 Object_Definition
=> Indic
,
1338 Expression
=> Incod
);
1343 -- If the call is to initialize a component of a composite type,
1344 -- and the component does not depend on discriminants, use the
1345 -- actual type of the component. This is required in case the
1346 -- component is constrained, because in general the formal of the
1347 -- initialization procedure will be unconstrained. Note that if
1348 -- the component being initialized is constrained by an enclosing
1349 -- discriminant, the presence of the initialization in the
1350 -- declaration will generate an expression for the actual subtype.
1352 Set_No_Initialization
(Decl
);
1353 Set_Object_Definition
(Decl
,
1354 New_Occurrence_Of
(Etype
(Actual
), Loc
));
1357 Insert_Action
(N
, Decl
);
1359 -- The actual is simply a reference to the temporary
1361 Rewrite
(Actual
, New_Occurrence_Of
(Temp
, Loc
));
1363 -- Generate copy out if OUT or IN OUT parameter
1365 if Ekind
(Formal
) /= E_In_Parameter
then
1367 Rhs
:= New_Occurrence_Of
(Temp
, Loc
);
1369 -- Deal with conversion
1371 if Nkind
(Lhs
) = N_Type_Conversion
then
1372 Lhs
:= Expression
(Lhs
);
1373 Rhs
:= Convert_To
(Etype
(Actual
), Rhs
);
1376 Append_To
(Post_Call
,
1377 Make_Assignment_Statement
(Loc
,
1379 Expression
=> Rhs
));
1380 Set_Assignment_OK
(Name
(Last
(Post_Call
)));
1382 end Add_Simple_Call_By_Copy_Code
;
1384 ---------------------------
1385 -- Check_Fortran_Logical --
1386 ---------------------------
1388 procedure Check_Fortran_Logical
is
1389 Logical
: constant Entity_Id
:= Etype
(Formal
);
1392 -- Note: this is very incomplete, e.g. it does not handle arrays
1393 -- of logical values. This is really not the right approach at all???)
1396 if Convention
(Subp
) = Convention_Fortran
1397 and then Root_Type
(Etype
(Formal
)) = Standard_Boolean
1398 and then Ekind
(Formal
) /= E_In_Parameter
1400 Var
:= Make_Var
(Actual
);
1401 Append_To
(Post_Call
,
1402 Make_Assignment_Statement
(Loc
,
1403 Name
=> New_Occurrence_Of
(Var
, Loc
),
1405 Unchecked_Convert_To
(
1408 Left_Opnd
=> New_Occurrence_Of
(Var
, Loc
),
1410 Unchecked_Convert_To
(
1412 New_Occurrence_Of
(Standard_False
, Loc
))))));
1414 end Check_Fortran_Logical
;
1420 function Is_Legal_Copy
return Boolean is
1422 -- An attempt to copy a value of such a type can only occur if
1423 -- representation clauses give the actual a misaligned address.
1425 if Is_By_Reference_Type
(Etype
(Formal
)) then
1427 -- If the front-end does not perform full type layout, the actual
1428 -- may in fact be properly aligned but there is not enough front-
1429 -- end information to determine this. In that case gigi will emit
1430 -- an error if a copy is not legal, or generate the proper code.
1431 -- For other backends we report the error now.
1433 -- Seems wrong to be issuing an error in the expander, since it
1434 -- will be missed in -gnatc mode ???
1436 if Frontend_Layout_On_Target
then
1438 ("misaligned actual cannot be passed by reference", Actual
);
1443 -- For users of Starlet, we assume that the specification of by-
1444 -- reference mechanism is mandatory. This may lead to unaligned
1445 -- objects but at least for DEC legacy code it is known to work.
1446 -- The warning will alert users of this code that a problem may
1449 elsif Mechanism
(Formal
) = By_Reference
1450 and then Is_Valued_Procedure
(Scope
(Formal
))
1453 ("by_reference actual may be misaligned??", Actual
);
1465 function Make_Var
(Actual
: Node_Id
) return Entity_Id
is
1469 if Is_Entity_Name
(Actual
) then
1470 return Entity
(Actual
);
1473 Var
:= Make_Temporary
(Loc
, 'T', Actual
);
1476 Make_Object_Renaming_Declaration
(Loc
,
1477 Defining_Identifier
=> Var
,
1479 New_Occurrence_Of
(Etype
(Actual
), Loc
),
1480 Name
=> Relocate_Node
(Actual
));
1482 Insert_Action
(N
, N_Node
);
1487 -------------------------
1488 -- Reset_Packed_Prefix --
1489 -------------------------
1491 procedure Reset_Packed_Prefix
is
1492 Pfx
: Node_Id
:= Actual
;
1495 Set_Analyzed
(Pfx
, False);
1497 not Nkind_In
(Pfx
, N_Selected_Component
, N_Indexed_Component
);
1498 Pfx
:= Prefix
(Pfx
);
1500 end Reset_Packed_Prefix
;
1502 -- Start of processing for Expand_Actuals
1505 Post_Call
:= New_List
;
1507 Formal
:= First_Formal
(Subp
);
1508 Actual
:= First_Actual
(N
);
1509 while Present
(Formal
) loop
1510 E_Formal
:= Etype
(Formal
);
1512 if Is_Scalar_Type
(E_Formal
)
1513 or else Nkind
(Actual
) = N_Slice
1515 Check_Fortran_Logical
;
1519 elsif Ekind
(Formal
) /= E_Out_Parameter
then
1521 -- The unusual case of the current instance of a protected type
1522 -- requires special handling. This can only occur in the context
1523 -- of a call within the body of a protected operation.
1525 if Is_Entity_Name
(Actual
)
1526 and then Ekind
(Entity
(Actual
)) = E_Protected_Type
1527 and then In_Open_Scopes
(Entity
(Actual
))
1529 if Scope
(Subp
) /= Entity
(Actual
) then
1531 ("operation outside protected type may not "
1532 & "call back its protected operations??", Actual
);
1536 Expand_Protected_Object_Reference
(N
, Entity
(Actual
)));
1539 -- Ada 2005 (AI-318-02): If the actual parameter is a call to a
1540 -- build-in-place function, then a temporary return object needs
1541 -- to be created and access to it must be passed to the function.
1542 -- Currently we limit such functions to those with inherently
1543 -- limited result subtypes, but eventually we plan to expand the
1544 -- functions that are treated as build-in-place to include other
1545 -- composite result types.
1547 if Is_Build_In_Place_Function_Call
(Actual
) then
1548 Make_Build_In_Place_Call_In_Anonymous_Context
(Actual
);
1551 Apply_Constraint_Check
(Actual
, E_Formal
);
1553 -- Out parameter case. No constraint checks on access type
1556 elsif Is_Access_Type
(E_Formal
) then
1561 elsif Has_Discriminants
(Base_Type
(E_Formal
))
1562 or else Has_Non_Null_Base_Init_Proc
(E_Formal
)
1564 Apply_Constraint_Check
(Actual
, E_Formal
);
1569 Apply_Constraint_Check
(Actual
, Base_Type
(E_Formal
));
1572 -- Processing for IN-OUT and OUT parameters
1574 if Ekind
(Formal
) /= E_In_Parameter
then
1576 -- For type conversions of arrays, apply length/range checks
1578 if Is_Array_Type
(E_Formal
)
1579 and then Nkind
(Actual
) = N_Type_Conversion
1581 if Is_Constrained
(E_Formal
) then
1582 Apply_Length_Check
(Expression
(Actual
), E_Formal
);
1584 Apply_Range_Check
(Expression
(Actual
), E_Formal
);
1588 -- If argument is a type conversion for a type that is passed
1589 -- by copy, then we must pass the parameter by copy.
1591 if Nkind
(Actual
) = N_Type_Conversion
1593 (Is_Numeric_Type
(E_Formal
)
1594 or else Is_Access_Type
(E_Formal
)
1595 or else Is_Enumeration_Type
(E_Formal
)
1596 or else Is_Bit_Packed_Array
(Etype
(Formal
))
1597 or else Is_Bit_Packed_Array
(Etype
(Expression
(Actual
)))
1599 -- Also pass by copy if change of representation
1601 or else not Same_Representation
1603 Etype
(Expression
(Actual
))))
1605 Add_Call_By_Copy_Code
;
1607 -- References to components of bit packed arrays are expanded
1608 -- at this point, rather than at the point of analysis of the
1609 -- actuals, to handle the expansion of the assignment to
1610 -- [in] out parameters.
1612 elsif Is_Ref_To_Bit_Packed_Array
(Actual
) then
1613 Add_Simple_Call_By_Copy_Code
;
1615 -- If a non-scalar actual is possibly bit-aligned, we need a copy
1616 -- because the back-end cannot cope with such objects. In other
1617 -- cases where alignment forces a copy, the back-end generates
1618 -- it properly. It should not be generated unconditionally in the
1619 -- front-end because it does not know precisely the alignment
1620 -- requirements of the target, and makes too conservative an
1621 -- estimate, leading to superfluous copies or spurious errors
1622 -- on by-reference parameters.
1624 elsif Nkind
(Actual
) = N_Selected_Component
1626 Component_May_Be_Bit_Aligned
(Entity
(Selector_Name
(Actual
)))
1627 and then not Represented_As_Scalar
(Etype
(Formal
))
1629 Add_Simple_Call_By_Copy_Code
;
1631 -- References to slices of bit packed arrays are expanded
1633 elsif Is_Ref_To_Bit_Packed_Slice
(Actual
) then
1634 Add_Call_By_Copy_Code
;
1636 -- References to possibly unaligned slices of arrays are expanded
1638 elsif Is_Possibly_Unaligned_Slice
(Actual
) then
1639 Add_Call_By_Copy_Code
;
1641 -- Deal with access types where the actual subtype and the
1642 -- formal subtype are not the same, requiring a check.
1644 -- It is necessary to exclude tagged types because of "downward
1645 -- conversion" errors.
1647 elsif Is_Access_Type
(E_Formal
)
1648 and then not Same_Type
(E_Formal
, Etype
(Actual
))
1649 and then not Is_Tagged_Type
(Designated_Type
(E_Formal
))
1651 Add_Call_By_Copy_Code
;
1653 -- If the actual is not a scalar and is marked for volatile
1654 -- treatment, whereas the formal is not volatile, then pass
1655 -- by copy unless it is a by-reference type.
1657 -- Note: we use Is_Volatile here rather than Treat_As_Volatile,
1658 -- because this is the enforcement of a language rule that applies
1659 -- only to "real" volatile variables, not e.g. to the address
1660 -- clause overlay case.
1662 elsif Is_Entity_Name
(Actual
)
1663 and then Is_Volatile
(Entity
(Actual
))
1664 and then not Is_By_Reference_Type
(Etype
(Actual
))
1665 and then not Is_Scalar_Type
(Etype
(Entity
(Actual
)))
1666 and then not Is_Volatile
(E_Formal
)
1668 Add_Call_By_Copy_Code
;
1670 elsif Nkind
(Actual
) = N_Indexed_Component
1671 and then Is_Entity_Name
(Prefix
(Actual
))
1672 and then Has_Volatile_Components
(Entity
(Prefix
(Actual
)))
1674 Add_Call_By_Copy_Code
;
1676 -- Add call-by-copy code for the case of scalar out parameters
1677 -- when it is not known at compile time that the subtype of the
1678 -- formal is a subrange of the subtype of the actual (or vice
1679 -- versa for in out parameters), in order to get range checks
1680 -- on such actuals. (Maybe this case should be handled earlier
1681 -- in the if statement???)
1683 elsif Is_Scalar_Type
(E_Formal
)
1685 (not In_Subrange_Of
(E_Formal
, Etype
(Actual
))
1687 (Ekind
(Formal
) = E_In_Out_Parameter
1688 and then not In_Subrange_Of
(Etype
(Actual
), E_Formal
)))
1690 -- Perhaps the setting back to False should be done within
1691 -- Add_Call_By_Copy_Code, since it could get set on other
1692 -- cases occurring above???
1694 if Do_Range_Check
(Actual
) then
1695 Set_Do_Range_Check
(Actual
, False);
1698 Add_Call_By_Copy_Code
;
1701 -- Processing for IN parameters
1704 -- For IN parameters is in the packed array case, we expand an
1705 -- indexed component (the circuit in Exp_Ch4 deliberately left
1706 -- indexed components appearing as actuals untouched, so that
1707 -- the special processing above for the OUT and IN OUT cases
1708 -- could be performed. We could make the test in Exp_Ch4 more
1709 -- complex and have it detect the parameter mode, but it is
1710 -- easier simply to handle all cases here.)
1712 if Nkind
(Actual
) = N_Indexed_Component
1713 and then Is_Packed
(Etype
(Prefix
(Actual
)))
1715 Reset_Packed_Prefix
;
1716 Expand_Packed_Element_Reference
(Actual
);
1718 -- If we have a reference to a bit packed array, we copy it, since
1719 -- the actual must be byte aligned.
1721 -- Is this really necessary in all cases???
1723 elsif Is_Ref_To_Bit_Packed_Array
(Actual
) then
1724 Add_Simple_Call_By_Copy_Code
;
1726 -- If a non-scalar actual is possibly unaligned, we need a copy
1728 elsif Is_Possibly_Unaligned_Object
(Actual
)
1729 and then not Represented_As_Scalar
(Etype
(Formal
))
1731 Add_Simple_Call_By_Copy_Code
;
1733 -- Similarly, we have to expand slices of packed arrays here
1734 -- because the result must be byte aligned.
1736 elsif Is_Ref_To_Bit_Packed_Slice
(Actual
) then
1737 Add_Call_By_Copy_Code
;
1739 -- Only processing remaining is to pass by copy if this is a
1740 -- reference to a possibly unaligned slice, since the caller
1741 -- expects an appropriately aligned argument.
1743 elsif Is_Possibly_Unaligned_Slice
(Actual
) then
1744 Add_Call_By_Copy_Code
;
1746 -- An unusual case: a current instance of an enclosing task can be
1747 -- an actual, and must be replaced by a reference to self.
1749 elsif Is_Entity_Name
(Actual
)
1750 and then Is_Task_Type
(Entity
(Actual
))
1752 if In_Open_Scopes
(Entity
(Actual
)) then
1754 (Make_Function_Call
(Loc
,
1755 Name
=> New_Reference_To
(RTE
(RE_Self
), Loc
))));
1758 -- A task type cannot otherwise appear as an actual
1761 raise Program_Error
;
1766 Next_Formal
(Formal
);
1767 Next_Actual
(Actual
);
1770 -- Find right place to put post call stuff if it is present
1772 if not Is_Empty_List
(Post_Call
) then
1774 -- Cases where the call is not a member of a statement list
1776 if not Is_List_Member
(N
) then
1778 P
: Node_Id
:= Parent
(N
);
1781 -- In Ada 2012 the call may be a function call in an expression
1782 -- (since OUT and IN OUT parameters are now allowed for such
1783 -- calls. The write-back of (in)-out parameters is handled
1784 -- by the back-end, but the constraint checks generated when
1785 -- subtypes of formal and actual don't match must be inserted
1786 -- in the form of assignments, at the nearest point after the
1787 -- declaration or statement that contains the call.
1789 if Ada_Version
>= Ada_2012
1790 and then Nkind
(N
) = N_Function_Call
1792 while Nkind
(P
) not in N_Declaration
1794 Nkind
(P
) not in N_Statement_Other_Than_Procedure_Call
1799 Insert_Actions_After
(P
, Post_Call
);
1801 -- If not the special Ada 2012 case of a function call, then
1802 -- we must have the triggering statement of a triggering
1803 -- alternative or an entry call alternative, and we can add
1804 -- the post call stuff to the corresponding statement list.
1807 pragma Assert
(Nkind_In
(P
, N_Triggering_Alternative
,
1808 N_Entry_Call_Alternative
));
1810 if Is_Non_Empty_List
(Statements
(P
)) then
1811 Insert_List_Before_And_Analyze
1812 (First
(Statements
(P
)), Post_Call
);
1814 Set_Statements
(P
, Post_Call
);
1820 -- Otherwise, normal case where N is in a statement sequence,
1821 -- just put the post-call stuff after the call statement.
1824 Insert_Actions_After
(N
, Post_Call
);
1828 -- The call node itself is re-analyzed in Expand_Call
1836 -- This procedure handles expansion of function calls and procedure call
1837 -- statements (i.e. it serves as the body for Expand_N_Function_Call and
1838 -- Expand_N_Procedure_Call_Statement). Processing for calls includes:
1840 -- Replace call to Raise_Exception by Raise_Exception_Always if possible
1841 -- Provide values of actuals for all formals in Extra_Formals list
1842 -- Replace "call" to enumeration literal function by literal itself
1843 -- Rewrite call to predefined operator as operator
1844 -- Replace actuals to in-out parameters that are numeric conversions,
1845 -- with explicit assignment to temporaries before and after the call.
1846 -- Remove optional actuals if First_Optional_Parameter specified.
1848 -- Note that the list of actuals has been filled with default expressions
1849 -- during semantic analysis of the call. Only the extra actuals required
1850 -- for the 'Constrained attribute and for accessibility checks are added
1853 procedure Expand_Call
(N
: Node_Id
) is
1854 Loc
: constant Source_Ptr
:= Sloc
(N
);
1855 Call_Node
: Node_Id
:= N
;
1856 Extra_Actuals
: List_Id
:= No_List
;
1857 Prev
: Node_Id
:= Empty
;
1859 procedure Add_Actual_Parameter
(Insert_Param
: Node_Id
);
1860 -- Adds one entry to the end of the actual parameter list. Used for
1861 -- default parameters and for extra actuals (for Extra_Formals). The
1862 -- argument is an N_Parameter_Association node.
1864 procedure Add_Extra_Actual
(Expr
: Node_Id
; EF
: Entity_Id
);
1865 -- Adds an extra actual to the list of extra actuals. Expr is the
1866 -- expression for the value of the actual, EF is the entity for the
1869 procedure Do_Inline
(Subp
: Entity_Id
; Orig_Subp
: Entity_Id
);
1870 -- Check and inline the body of Subp. Invoked when compiling with
1871 -- optimizations enabled and Subp has pragma inline or inline always.
1872 -- If the subprogram is a renaming, or if it is inherited, then Subp
1873 -- references the renamed entity and Orig_Subp is the entity of the
1876 procedure Do_Inline_Always
(Subp
: Entity_Id
; Orig_Subp
: Entity_Id
);
1877 -- Check and inline the body of Subp. Invoked when compiling without
1878 -- optimizations and Subp has pragma inline always. If the subprogram is
1879 -- a renaming, or if it is inherited, then Subp references the renamed
1880 -- entity and Orig_Subp is the entity of the call node N.
1882 function Inherited_From_Formal
(S
: Entity_Id
) return Entity_Id
;
1883 -- Within an instance, a type derived from a non-tagged formal derived
1884 -- type inherits from the original parent, not from the actual. The
1885 -- current derivation mechanism has the derived type inherit from the
1886 -- actual, which is only correct outside of the instance. If the
1887 -- subprogram is inherited, we test for this particular case through a
1888 -- convoluted tree traversal before setting the proper subprogram to be
1891 function In_Unfrozen_Instance
(E
: Entity_Id
) return Boolean;
1892 -- Return true if E comes from an instance that is not yet frozen
1894 function Is_Direct_Deep_Call
(Subp
: Entity_Id
) return Boolean;
1895 -- Determine if Subp denotes a non-dispatching call to a Deep routine
1897 function New_Value
(From
: Node_Id
) return Node_Id
;
1898 -- From is the original Expression. New_Value is equivalent to a call
1899 -- to Duplicate_Subexpr with an explicit dereference when From is an
1900 -- access parameter.
1902 --------------------------
1903 -- Add_Actual_Parameter --
1904 --------------------------
1906 procedure Add_Actual_Parameter
(Insert_Param
: Node_Id
) is
1907 Actual_Expr
: constant Node_Id
:=
1908 Explicit_Actual_Parameter
(Insert_Param
);
1911 -- Case of insertion is first named actual
1913 if No
(Prev
) or else
1914 Nkind
(Parent
(Prev
)) /= N_Parameter_Association
1916 Set_Next_Named_Actual
1917 (Insert_Param
, First_Named_Actual
(Call_Node
));
1918 Set_First_Named_Actual
(Call_Node
, Actual_Expr
);
1921 if No
(Parameter_Associations
(Call_Node
)) then
1922 Set_Parameter_Associations
(Call_Node
, New_List
);
1925 Append
(Insert_Param
, Parameter_Associations
(Call_Node
));
1928 Insert_After
(Prev
, Insert_Param
);
1931 -- Case of insertion is not first named actual
1934 Set_Next_Named_Actual
1935 (Insert_Param
, Next_Named_Actual
(Parent
(Prev
)));
1936 Set_Next_Named_Actual
(Parent
(Prev
), Actual_Expr
);
1937 Append
(Insert_Param
, Parameter_Associations
(Call_Node
));
1940 Prev
:= Actual_Expr
;
1941 end Add_Actual_Parameter
;
1943 ----------------------
1944 -- Add_Extra_Actual --
1945 ----------------------
1947 procedure Add_Extra_Actual
(Expr
: Node_Id
; EF
: Entity_Id
) is
1948 Loc
: constant Source_Ptr
:= Sloc
(Expr
);
1951 if Extra_Actuals
= No_List
then
1952 Extra_Actuals
:= New_List
;
1953 Set_Parent
(Extra_Actuals
, Call_Node
);
1956 Append_To
(Extra_Actuals
,
1957 Make_Parameter_Association
(Loc
,
1958 Selector_Name
=> Make_Identifier
(Loc
, Chars
(EF
)),
1959 Explicit_Actual_Parameter
=> Expr
));
1961 Analyze_And_Resolve
(Expr
, Etype
(EF
));
1963 if Nkind
(Call_Node
) = N_Function_Call
then
1964 Set_Is_Accessibility_Actual
(Parent
(Expr
));
1966 end Add_Extra_Actual
;
1972 procedure Do_Inline
(Subp
: Entity_Id
; Orig_Subp
: Entity_Id
) is
1973 Spec
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
1975 procedure Do_Backend_Inline
;
1976 -- Check that the call can be safely passed to the backend. If true
1977 -- then register the enclosing unit of Subp to Inlined_Bodies so that
1978 -- the body of Subp can be retrieved and analyzed by the backend.
1980 procedure Register_Backend_Call
(N
: Node_Id
);
1981 -- Append N to the list Backend_Calls
1983 -----------------------
1984 -- Do_Backend_Inline --
1985 -----------------------
1987 procedure Do_Backend_Inline
is
1989 -- No extra test needed for init subprograms since we know they
1990 -- are available to the backend!
1992 if Is_Init_Proc
(Subp
) then
1993 Add_Inlined_Body
(Subp
);
1994 Register_Backend_Call
(Call_Node
);
1996 -- Verify that if the body to inline is located in the current
1997 -- unit the inlining does not occur earlier. This avoids
1998 -- order-of-elaboration problems in the back end.
2000 elsif In_Same_Extended_Unit
(Call_Node
, Subp
)
2001 and then Nkind
(Spec
) = N_Subprogram_Declaration
2002 and then Earlier_In_Extended_Unit
2003 (Loc
, Sloc
(Body_To_Inline
(Spec
)))
2006 ("cannot inline& (body not seen yet)??", Call_Node
, Subp
);
2010 Backend_Inline
: Boolean := True;
2013 -- If we are compiling a package body that is not the
2014 -- main unit, it must be for inlining/instantiation
2015 -- purposes, in which case we inline the call to insure
2016 -- that the same temporaries are generated when compiling
2017 -- the body by itself. Otherwise link errors can occur.
2019 -- If the function being called is itself in the main
2020 -- unit, we cannot inline, because there is a risk of
2021 -- double elaboration and/or circularity: the inlining
2022 -- can make visible a private entity in the body of the
2023 -- main unit, that gigi will see before its sees its
2024 -- proper definition.
2026 if not (In_Extended_Main_Code_Unit
(Call_Node
))
2027 and then In_Package_Body
2030 not In_Extended_Main_Source_Unit
(Subp
);
2033 if Backend_Inline
then
2034 Add_Inlined_Body
(Subp
);
2035 Register_Backend_Call
(Call_Node
);
2039 end Do_Backend_Inline
;
2041 ---------------------------
2042 -- Register_Backend_Call --
2043 ---------------------------
2045 procedure Register_Backend_Call
(N
: Node_Id
) is
2047 if Backend_Calls
= No_Elist
then
2048 Backend_Calls
:= New_Elmt_List
;
2051 Append_Elmt
(N
, To
=> Backend_Calls
);
2052 end Register_Backend_Call
;
2054 -- Start of processing for Do_Inline
2057 -- Verify that the body to inline has already been seen
2060 or else Nkind
(Spec
) /= N_Subprogram_Declaration
2061 or else No
(Body_To_Inline
(Spec
))
2063 if Comes_From_Source
(Subp
)
2064 and then Must_Inline
(Subp
)
2067 ("cannot inline& (body not seen yet)?", Call_Node
, Subp
);
2069 -- Let the back end handle it
2076 -- If this an inherited function that returns a private type, do not
2077 -- inline if the full view is an unconstrained array, because such
2078 -- calls cannot be inlined.
2080 elsif Present
(Orig_Subp
)
2081 and then Is_Array_Type
(Etype
(Orig_Subp
))
2082 and then not Is_Constrained
(Etype
(Orig_Subp
))
2085 ("cannot inline& (unconstrained array)?", Call_Node
, Subp
);
2088 Expand_Inlined_Call
(Call_Node
, Subp
, Orig_Subp
);
2092 ----------------------
2093 -- Do_Inline_Always --
2094 ----------------------
2096 procedure Do_Inline_Always
(Subp
: Entity_Id
; Orig_Subp
: Entity_Id
) is
2097 Spec
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
2098 Body_Id
: Entity_Id
;
2102 or else Nkind
(Spec
) /= N_Subprogram_Declaration
2103 or else No
(Body_To_Inline
(Spec
))
2104 or else Serious_Errors_Detected
/= 0
2109 Body_Id
:= Corresponding_Body
(Spec
);
2111 -- Verify that the body to inline has already been seen
2114 or else not Analyzed
(Body_Id
)
2116 Set_Is_Inlined
(Subp
, False);
2118 if Comes_From_Source
(Subp
) then
2120 -- Report a warning only if the call is located in the unit of
2121 -- the called subprogram; otherwise it is an error.
2123 if not In_Same_Extended_Unit
(Call_Node
, Subp
) then
2125 ("cannot inline& (body not seen yet)?", Call_Node
, Subp
,
2126 Is_Serious
=> True);
2128 elsif In_Open_Scopes
(Subp
) then
2130 -- For backward compatibility we generate the same error
2131 -- or warning of the previous implementation. This will
2132 -- be changed when we definitely incorporate the new
2135 if Front_End_Inlining
2136 and then Optimization_Level
= 0
2139 ("call to recursive subprogram cannot be inlined?p?",
2142 -- Do not emit error compiling runtime packages
2144 elsif Is_Predefined_File_Name
2145 (Unit_File_Name
(Get_Source_Unit
(Subp
)))
2148 ("call to recursive subprogram cannot be inlined??",
2153 ("call to recursive subprogram cannot be inlined",
2159 ("cannot inline& (body not seen yet)?", Call_Node
, Subp
);
2165 -- If this an inherited function that returns a private type, do not
2166 -- inline if the full view is an unconstrained array, because such
2167 -- calls cannot be inlined.
2169 elsif Present
(Orig_Subp
)
2170 and then Is_Array_Type
(Etype
(Orig_Subp
))
2171 and then not Is_Constrained
(Etype
(Orig_Subp
))
2174 ("cannot inline& (unconstrained array)?", Call_Node
, Subp
);
2176 -- If the called subprogram comes from an instance in the same
2177 -- unit, and the instance is not yet frozen, inlining might
2178 -- trigger order-of-elaboration problems.
2180 elsif In_Unfrozen_Instance
(Scope
(Subp
)) then
2182 ("cannot inline& (unfrozen instance)?", Call_Node
, Subp
);
2185 Expand_Inlined_Call
(Call_Node
, Subp
, Orig_Subp
);
2187 end Do_Inline_Always
;
2189 ---------------------------
2190 -- Inherited_From_Formal --
2191 ---------------------------
2193 function Inherited_From_Formal
(S
: Entity_Id
) return Entity_Id
is
2195 Gen_Par
: Entity_Id
;
2196 Gen_Prim
: Elist_Id
;
2201 -- If the operation is inherited, it is attached to the corresponding
2202 -- type derivation. If the parent in the derivation is a generic
2203 -- actual, it is a subtype of the actual, and we have to recover the
2204 -- original derived type declaration to find the proper parent.
2206 if Nkind
(Parent
(S
)) /= N_Full_Type_Declaration
2207 or else not Is_Derived_Type
(Defining_Identifier
(Parent
(S
)))
2208 or else Nkind
(Type_Definition
(Original_Node
(Parent
(S
)))) /=
2209 N_Derived_Type_Definition
2210 or else not In_Instance
2217 (Type_Definition
(Original_Node
(Parent
(S
))));
2219 if Nkind
(Indic
) = N_Subtype_Indication
then
2220 Par
:= Entity
(Subtype_Mark
(Indic
));
2222 Par
:= Entity
(Indic
);
2226 if not Is_Generic_Actual_Type
(Par
)
2227 or else Is_Tagged_Type
(Par
)
2228 or else Nkind
(Parent
(Par
)) /= N_Subtype_Declaration
2229 or else not In_Open_Scopes
(Scope
(Par
))
2233 Gen_Par
:= Generic_Parent_Type
(Parent
(Par
));
2236 -- If the actual has no generic parent type, the formal is not
2237 -- a formal derived type, so nothing to inherit.
2239 if No
(Gen_Par
) then
2243 -- If the generic parent type is still the generic type, this is a
2244 -- private formal, not a derived formal, and there are no operations
2245 -- inherited from the formal.
2247 if Nkind
(Parent
(Gen_Par
)) = N_Formal_Type_Declaration
then
2251 Gen_Prim
:= Collect_Primitive_Operations
(Gen_Par
);
2253 Elmt
:= First_Elmt
(Gen_Prim
);
2254 while Present
(Elmt
) loop
2255 if Chars
(Node
(Elmt
)) = Chars
(S
) then
2261 F1
:= First_Formal
(S
);
2262 F2
:= First_Formal
(Node
(Elmt
));
2264 and then Present
(F2
)
2266 if Etype
(F1
) = Etype
(F2
)
2267 or else Etype
(F2
) = Gen_Par
2273 exit; -- not the right subprogram
2285 raise Program_Error
;
2286 end Inherited_From_Formal
;
2288 --------------------------
2289 -- In_Unfrozen_Instance --
2290 --------------------------
2292 function In_Unfrozen_Instance
(E
: Entity_Id
) return Boolean is
2297 while Present
(S
) and then S
/= Standard_Standard
loop
2298 if Is_Generic_Instance
(S
)
2299 and then Present
(Freeze_Node
(S
))
2300 and then not Analyzed
(Freeze_Node
(S
))
2309 end In_Unfrozen_Instance
;
2311 -------------------------
2312 -- Is_Direct_Deep_Call --
2313 -------------------------
2315 function Is_Direct_Deep_Call
(Subp
: Entity_Id
) return Boolean is
2317 if Is_TSS
(Subp
, TSS_Deep_Adjust
)
2318 or else Is_TSS
(Subp
, TSS_Deep_Finalize
)
2319 or else Is_TSS
(Subp
, TSS_Deep_Initialize
)
2326 Actual
:= First
(Parameter_Associations
(N
));
2327 Formal
:= First_Formal
(Subp
);
2328 while Present
(Actual
)
2329 and then Present
(Formal
)
2331 if Nkind
(Actual
) = N_Identifier
2332 and then Is_Controlling_Actual
(Actual
)
2333 and then Etype
(Actual
) = Etype
(Formal
)
2339 Next_Formal
(Formal
);
2345 end Is_Direct_Deep_Call
;
2351 function New_Value
(From
: Node_Id
) return Node_Id
is
2352 Res
: constant Node_Id
:= Duplicate_Subexpr
(From
);
2354 if Is_Access_Type
(Etype
(From
)) then
2355 return Make_Explicit_Dereference
(Sloc
(From
), Prefix
=> Res
);
2363 Curr_S
: constant Entity_Id
:= Current_Scope
;
2364 Remote
: constant Boolean := Is_Remote_Call
(Call_Node
);
2367 Orig_Subp
: Entity_Id
:= Empty
;
2368 Param_Count
: Natural := 0;
2369 Parent_Formal
: Entity_Id
;
2370 Parent_Subp
: Entity_Id
;
2374 Prev_Orig
: Node_Id
;
2375 -- Original node for an actual, which may have been rewritten. If the
2376 -- actual is a function call that has been transformed from a selected
2377 -- component, the original node is unanalyzed. Otherwise, it carries
2378 -- semantic information used to generate additional actuals.
2380 CW_Interface_Formals_Present
: Boolean := False;
2382 -- Start of processing for Expand_Call
2385 -- Expand the procedure call if the first actual has a dimension and if
2386 -- the procedure is Put (Ada 2012).
2388 if Ada_Version
>= Ada_2012
2389 and then Nkind
(Call_Node
) = N_Procedure_Call_Statement
2390 and then Present
(Parameter_Associations
(Call_Node
))
2392 Expand_Put_Call_With_Symbol
(Call_Node
);
2395 -- Ignore if previous error
2397 if Nkind
(Call_Node
) in N_Has_Etype
2398 and then Etype
(Call_Node
) = Any_Type
2403 -- Call using access to subprogram with explicit dereference
2405 if Nkind
(Name
(Call_Node
)) = N_Explicit_Dereference
then
2406 Subp
:= Etype
(Name
(Call_Node
));
2407 Parent_Subp
:= Empty
;
2409 -- Case of call to simple entry, where the Name is a selected component
2410 -- whose prefix is the task, and whose selector name is the entry name
2412 elsif Nkind
(Name
(Call_Node
)) = N_Selected_Component
then
2413 Subp
:= Entity
(Selector_Name
(Name
(Call_Node
)));
2414 Parent_Subp
:= Empty
;
2416 -- Case of call to member of entry family, where Name is an indexed
2417 -- component, with the prefix being a selected component giving the
2418 -- task and entry family name, and the index being the entry index.
2420 elsif Nkind
(Name
(Call_Node
)) = N_Indexed_Component
then
2421 Subp
:= Entity
(Selector_Name
(Prefix
(Name
(Call_Node
))));
2422 Parent_Subp
:= Empty
;
2427 Subp
:= Entity
(Name
(Call_Node
));
2428 Parent_Subp
:= Alias
(Subp
);
2430 -- Replace call to Raise_Exception by call to Raise_Exception_Always
2431 -- if we can tell that the first parameter cannot possibly be null.
2432 -- This improves efficiency by avoiding a run-time test.
2434 -- We do not do this if Raise_Exception_Always does not exist, which
2435 -- can happen in configurable run time profiles which provide only a
2438 if Is_RTE
(Subp
, RE_Raise_Exception
)
2439 and then RTE_Available
(RE_Raise_Exception_Always
)
2442 FA
: constant Node_Id
:=
2443 Original_Node
(First_Actual
(Call_Node
));
2446 -- The case we catch is where the first argument is obtained
2447 -- using the Identity attribute (which must always be
2450 if Nkind
(FA
) = N_Attribute_Reference
2451 and then Attribute_Name
(FA
) = Name_Identity
2453 Subp
:= RTE
(RE_Raise_Exception_Always
);
2454 Set_Name
(Call_Node
, New_Occurrence_Of
(Subp
, Loc
));
2459 if Ekind
(Subp
) = E_Entry
then
2460 Parent_Subp
:= Empty
;
2464 -- Detect the following code in System.Finalization_Masters only on
2465 -- .NET/JVM targets:
2467 -- procedure Finalize (Master : in out Finalization_Master) is
2471 -- Finalize (Curr_Ptr.all);
2473 -- Since .NET/JVM compilers lack address arithmetic and Deep_Finalize
2474 -- cannot be named in library or user code, the compiler has to install
2475 -- a kludge and transform the call to Finalize into Deep_Finalize.
2477 if VM_Target
/= No_VM
2478 and then Chars
(Subp
) = Name_Finalize
2479 and then Ekind
(Curr_S
) = E_Block
2480 and then Ekind
(Scope
(Curr_S
)) = E_Procedure
2481 and then Chars
(Scope
(Curr_S
)) = Name_Finalize
2482 and then Etype
(First_Formal
(Scope
(Curr_S
))) =
2483 RTE
(RE_Finalization_Master
)
2486 Deep_Fin
: constant Entity_Id
:=
2487 Find_Prim_Op
(RTE
(RE_Root_Controlled
),
2490 -- Since Root_Controlled is a tagged type, the compiler should
2491 -- always generate Deep_Finalize for it.
2493 pragma Assert
(Present
(Deep_Fin
));
2496 -- Deep_Finalize (Curr_Ptr.all);
2499 Make_Procedure_Call_Statement
(Loc
,
2501 New_Reference_To
(Deep_Fin
, Loc
),
2502 Parameter_Associations
=>
2503 New_Copy_List_Tree
(Parameter_Associations
(N
))));
2510 -- Ada 2005 (AI-345): We have a procedure call as a triggering
2511 -- alternative in an asynchronous select or as an entry call in
2512 -- a conditional or timed select. Check whether the procedure call
2513 -- is a renaming of an entry and rewrite it as an entry call.
2515 if Ada_Version
>= Ada_2005
2516 and then Nkind
(Call_Node
) = N_Procedure_Call_Statement
2518 ((Nkind
(Parent
(Call_Node
)) = N_Triggering_Alternative
2519 and then Triggering_Statement
(Parent
(Call_Node
)) = Call_Node
)
2521 (Nkind
(Parent
(Call_Node
)) = N_Entry_Call_Alternative
2522 and then Entry_Call_Statement
(Parent
(Call_Node
)) = Call_Node
))
2526 Ren_Root
: Entity_Id
:= Subp
;
2529 -- This may be a chain of renamings, find the root
2531 if Present
(Alias
(Ren_Root
)) then
2532 Ren_Root
:= Alias
(Ren_Root
);
2535 if Present
(Original_Node
(Parent
(Parent
(Ren_Root
)))) then
2536 Ren_Decl
:= Original_Node
(Parent
(Parent
(Ren_Root
)));
2538 if Nkind
(Ren_Decl
) = N_Subprogram_Renaming_Declaration
then
2540 Make_Entry_Call_Statement
(Loc
,
2542 New_Copy_Tree
(Name
(Ren_Decl
)),
2543 Parameter_Associations
=>
2545 (Parameter_Associations
(Call_Node
))));
2553 -- First step, compute extra actuals, corresponding to any Extra_Formals
2554 -- present. Note that we do not access Extra_Formals directly, instead
2555 -- we simply note the presence of the extra formals as we process the
2556 -- regular formals collecting corresponding actuals in Extra_Actuals.
2558 -- We also generate any required range checks for actuals for in formals
2559 -- as we go through the loop, since this is a convenient place to do it.
2560 -- (Though it seems that this would be better done in Expand_Actuals???)
2562 Formal
:= First_Formal
(Subp
);
2563 Actual
:= First_Actual
(Call_Node
);
2565 while Present
(Formal
) loop
2567 -- Generate range check if required
2569 if Do_Range_Check
(Actual
)
2570 and then Ekind
(Formal
) = E_In_Parameter
2572 Set_Do_Range_Check
(Actual
, False);
2573 Generate_Range_Check
2574 (Actual
, Etype
(Formal
), CE_Range_Check_Failed
);
2577 -- Prepare to examine current entry
2580 Prev_Orig
:= Original_Node
(Prev
);
2582 -- Ada 2005 (AI-251): Check if any formal is a class-wide interface
2583 -- to expand it in a further round.
2585 CW_Interface_Formals_Present
:=
2586 CW_Interface_Formals_Present
2588 (Ekind
(Etype
(Formal
)) = E_Class_Wide_Type
2589 and then Is_Interface
(Etype
(Etype
(Formal
))))
2591 (Ekind
(Etype
(Formal
)) = E_Anonymous_Access_Type
2592 and then Is_Interface
(Directly_Designated_Type
2593 (Etype
(Etype
(Formal
)))));
2595 -- Create possible extra actual for constrained case. Usually, the
2596 -- extra actual is of the form actual'constrained, but since this
2597 -- attribute is only available for unconstrained records, TRUE is
2598 -- expanded if the type of the formal happens to be constrained (for
2599 -- instance when this procedure is inherited from an unconstrained
2600 -- record to a constrained one) or if the actual has no discriminant
2601 -- (its type is constrained). An exception to this is the case of a
2602 -- private type without discriminants. In this case we pass FALSE
2603 -- because the object has underlying discriminants with defaults.
2605 if Present
(Extra_Constrained
(Formal
)) then
2606 if Ekind
(Etype
(Prev
)) in Private_Kind
2607 and then not Has_Discriminants
(Base_Type
(Etype
(Prev
)))
2610 (New_Occurrence_Of
(Standard_False
, Loc
),
2611 Extra_Constrained
(Formal
));
2613 elsif Is_Constrained
(Etype
(Formal
))
2614 or else not Has_Discriminants
(Etype
(Prev
))
2617 (New_Occurrence_Of
(Standard_True
, Loc
),
2618 Extra_Constrained
(Formal
));
2620 -- Do not produce extra actuals for Unchecked_Union parameters.
2621 -- Jump directly to the end of the loop.
2623 elsif Is_Unchecked_Union
(Base_Type
(Etype
(Actual
))) then
2624 goto Skip_Extra_Actual_Generation
;
2627 -- If the actual is a type conversion, then the constrained
2628 -- test applies to the actual, not the target type.
2634 -- Test for unchecked conversions as well, which can occur
2635 -- as out parameter actuals on calls to stream procedures.
2638 while Nkind_In
(Act_Prev
, N_Type_Conversion
,
2639 N_Unchecked_Type_Conversion
)
2641 Act_Prev
:= Expression
(Act_Prev
);
2644 -- If the expression is a conversion of a dereference, this
2645 -- is internally generated code that manipulates addresses,
2646 -- e.g. when building interface tables. No check should
2647 -- occur in this case, and the discriminated object is not
2650 if not Comes_From_Source
(Actual
)
2651 and then Nkind
(Actual
) = N_Unchecked_Type_Conversion
2652 and then Nkind
(Act_Prev
) = N_Explicit_Dereference
2655 (New_Occurrence_Of
(Standard_False
, Loc
),
2656 Extra_Constrained
(Formal
));
2660 (Make_Attribute_Reference
(Sloc
(Prev
),
2662 Duplicate_Subexpr_No_Checks
2663 (Act_Prev
, Name_Req
=> True),
2664 Attribute_Name
=> Name_Constrained
),
2665 Extra_Constrained
(Formal
));
2671 -- Create possible extra actual for accessibility level
2673 if Present
(Extra_Accessibility
(Formal
)) then
2675 -- Ada 2005 (AI-252): If the actual was rewritten as an Access
2676 -- attribute, then the original actual may be an aliased object
2677 -- occurring as the prefix in a call using "Object.Operation"
2678 -- notation. In that case we must pass the level of the object,
2679 -- so Prev_Orig is reset to Prev and the attribute will be
2680 -- processed by the code for Access attributes further below.
2682 if Prev_Orig
/= Prev
2683 and then Nkind
(Prev
) = N_Attribute_Reference
2685 Get_Attribute_Id
(Attribute_Name
(Prev
)) = Attribute_Access
2686 and then Is_Aliased_View
(Prev_Orig
)
2691 -- Ada 2005 (AI-251): Thunks must propagate the extra actuals of
2692 -- accessibility levels.
2694 if Ekind
(Current_Scope
) in Subprogram_Kind
2695 and then Is_Thunk
(Current_Scope
)
2698 Parm_Ent
: Entity_Id
;
2701 if Is_Controlling_Actual
(Actual
) then
2703 -- Find the corresponding actual of the thunk
2705 Parm_Ent
:= First_Entity
(Current_Scope
);
2706 for J
in 2 .. Param_Count
loop
2707 Next_Entity
(Parm_Ent
);
2710 -- Handle unchecked conversion of access types generated
2711 -- in thunks (cf. Expand_Interface_Thunk).
2713 elsif Is_Access_Type
(Etype
(Actual
))
2714 and then Nkind
(Actual
) = N_Unchecked_Type_Conversion
2716 Parm_Ent
:= Entity
(Expression
(Actual
));
2718 else pragma Assert
(Is_Entity_Name
(Actual
));
2719 Parm_Ent
:= Entity
(Actual
);
2723 (New_Occurrence_Of
(Extra_Accessibility
(Parm_Ent
), Loc
),
2724 Extra_Accessibility
(Formal
));
2727 elsif Is_Entity_Name
(Prev_Orig
) then
2729 -- When passing an access parameter, or a renaming of an access
2730 -- parameter, as the actual to another access parameter we need
2731 -- to pass along the actual's own access level parameter. This
2732 -- is done if we are within the scope of the formal access
2733 -- parameter (if this is an inlined body the extra formal is
2736 if (Is_Formal
(Entity
(Prev_Orig
))
2738 (Present
(Renamed_Object
(Entity
(Prev_Orig
)))
2740 Is_Entity_Name
(Renamed_Object
(Entity
(Prev_Orig
)))
2743 (Entity
(Renamed_Object
(Entity
(Prev_Orig
))))))
2744 and then Ekind
(Etype
(Prev_Orig
)) = E_Anonymous_Access_Type
2745 and then In_Open_Scopes
(Scope
(Entity
(Prev_Orig
)))
2748 Parm_Ent
: constant Entity_Id
:= Param_Entity
(Prev_Orig
);
2751 pragma Assert
(Present
(Parm_Ent
));
2753 if Present
(Extra_Accessibility
(Parm_Ent
)) then
2756 (Extra_Accessibility
(Parm_Ent
), Loc
),
2757 Extra_Accessibility
(Formal
));
2759 -- If the actual access parameter does not have an
2760 -- associated extra formal providing its scope level,
2761 -- then treat the actual as having library-level
2766 (Make_Integer_Literal
(Loc
,
2767 Intval
=> Scope_Depth
(Standard_Standard
)),
2768 Extra_Accessibility
(Formal
));
2772 -- The actual is a normal access value, so just pass the level
2773 -- of the actual's access type.
2777 (Dynamic_Accessibility_Level
(Prev_Orig
),
2778 Extra_Accessibility
(Formal
));
2781 -- If the actual is an access discriminant, then pass the level
2782 -- of the enclosing object (RM05-3.10.2(12.4/2)).
2784 elsif Nkind
(Prev_Orig
) = N_Selected_Component
2785 and then Ekind
(Entity
(Selector_Name
(Prev_Orig
))) =
2787 and then Ekind
(Etype
(Entity
(Selector_Name
(Prev_Orig
)))) =
2788 E_Anonymous_Access_Type
2791 (Make_Integer_Literal
(Loc
,
2792 Intval
=> Object_Access_Level
(Prefix
(Prev_Orig
))),
2793 Extra_Accessibility
(Formal
));
2798 case Nkind
(Prev_Orig
) is
2800 when N_Attribute_Reference
=>
2801 case Get_Attribute_Id
(Attribute_Name
(Prev_Orig
)) is
2803 -- For X'Access, pass on the level of the prefix X
2805 when Attribute_Access
=>
2807 -- If this is an Access attribute applied to the
2808 -- the current instance object passed to a type
2809 -- initialization procedure, then use the level
2810 -- of the type itself. This is not really correct,
2811 -- as there should be an extra level parameter
2812 -- passed in with _init formals (only in the case
2813 -- where the type is immutably limited), but we
2814 -- don't have an easy way currently to create such
2815 -- an extra formal (init procs aren't ever frozen).
2816 -- For now we just use the level of the type,
2817 -- which may be too shallow, but that works better
2818 -- than passing Object_Access_Level of the type,
2819 -- which can be one level too deep in some cases.
2822 if Is_Entity_Name
(Prefix
(Prev_Orig
))
2823 and then Is_Type
(Entity
(Prefix
(Prev_Orig
)))
2826 (Make_Integer_Literal
(Loc
,
2829 (Entity
(Prefix
(Prev_Orig
)))),
2830 Extra_Accessibility
(Formal
));
2834 (Make_Integer_Literal
(Loc
,
2837 (Prefix
(Prev_Orig
))),
2838 Extra_Accessibility
(Formal
));
2841 -- Treat the unchecked attributes as library-level
2843 when Attribute_Unchecked_Access |
2844 Attribute_Unrestricted_Access
=>
2846 (Make_Integer_Literal
(Loc
,
2847 Intval
=> Scope_Depth
(Standard_Standard
)),
2848 Extra_Accessibility
(Formal
));
2850 -- No other cases of attributes returning access
2851 -- values that can be passed to access parameters.
2854 raise Program_Error
;
2858 -- For allocators we pass the level of the execution of the
2859 -- called subprogram, which is one greater than the current
2864 (Make_Integer_Literal
(Loc
,
2865 Intval
=> Scope_Depth
(Current_Scope
) + 1),
2866 Extra_Accessibility
(Formal
));
2868 -- For most other cases we simply pass the level of the
2869 -- actual's access type. The type is retrieved from
2870 -- Prev rather than Prev_Orig, because in some cases
2871 -- Prev_Orig denotes an original expression that has
2872 -- not been analyzed.
2876 (Dynamic_Accessibility_Level
(Prev
),
2877 Extra_Accessibility
(Formal
));
2882 -- Perform the check of 4.6(49) that prevents a null value from being
2883 -- passed as an actual to an access parameter. Note that the check
2884 -- is elided in the common cases of passing an access attribute or
2885 -- access parameter as an actual. Also, we currently don't enforce
2886 -- this check for expander-generated actuals and when -gnatdj is set.
2888 if Ada_Version
>= Ada_2005
then
2890 -- Ada 2005 (AI-231): Check null-excluding access types. Note that
2891 -- the intent of 6.4.1(13) is that null-exclusion checks should
2892 -- not be done for 'out' parameters, even though it refers only
2893 -- to constraint checks, and a null_exclusion is not a constraint.
2894 -- Note that AI05-0196-1 corrects this mistake in the RM.
2896 if Is_Access_Type
(Etype
(Formal
))
2897 and then Can_Never_Be_Null
(Etype
(Formal
))
2898 and then Ekind
(Formal
) /= E_Out_Parameter
2899 and then Nkind
(Prev
) /= N_Raise_Constraint_Error
2900 and then (Known_Null
(Prev
)
2901 or else not Can_Never_Be_Null
(Etype
(Prev
)))
2903 Install_Null_Excluding_Check
(Prev
);
2906 -- Ada_Version < Ada_2005
2909 if Ekind
(Etype
(Formal
)) /= E_Anonymous_Access_Type
2910 or else Access_Checks_Suppressed
(Subp
)
2914 elsif Debug_Flag_J
then
2917 elsif not Comes_From_Source
(Prev
) then
2920 elsif Is_Entity_Name
(Prev
)
2921 and then Ekind
(Etype
(Prev
)) = E_Anonymous_Access_Type
2925 elsif Nkind_In
(Prev
, N_Allocator
, N_Attribute_Reference
) then
2928 -- Suppress null checks when passing to access parameters of Java
2929 -- and CIL subprograms. (Should this be done for other foreign
2930 -- conventions as well ???)
2932 elsif Convention
(Subp
) = Convention_Java
2933 or else Convention
(Subp
) = Convention_CIL
2938 Install_Null_Excluding_Check
(Prev
);
2942 -- Perform appropriate validity checks on parameters that
2945 if Validity_Checks_On
then
2946 if (Ekind
(Formal
) = E_In_Parameter
2947 and then Validity_Check_In_Params
)
2949 (Ekind
(Formal
) = E_In_Out_Parameter
2950 and then Validity_Check_In_Out_Params
)
2952 -- If the actual is an indexed component of a packed type (or
2953 -- is an indexed or selected component whose prefix recursively
2954 -- meets this condition), it has not been expanded yet. It will
2955 -- be copied in the validity code that follows, and has to be
2956 -- expanded appropriately, so reanalyze it.
2958 -- What we do is just to unset analyzed bits on prefixes till
2959 -- we reach something that does not have a prefix.
2966 while Nkind_In
(Nod
, N_Indexed_Component
,
2967 N_Selected_Component
)
2969 Set_Analyzed
(Nod
, False);
2970 Nod
:= Prefix
(Nod
);
2974 Ensure_Valid
(Actual
);
2978 -- For Ada 2012, if a parameter is aliased, the actual must be a
2979 -- tagged type or an aliased view of an object.
2981 if Is_Aliased
(Formal
)
2982 and then not Is_Aliased_View
(Actual
)
2983 and then not Is_Tagged_Type
(Etype
(Formal
))
2986 ("actual for aliased formal& must be aliased object",
2990 -- For IN OUT and OUT parameters, ensure that subscripts are valid
2991 -- since this is a left side reference. We only do this for calls
2992 -- from the source program since we assume that compiler generated
2993 -- calls explicitly generate any required checks. We also need it
2994 -- only if we are doing standard validity checks, since clearly it is
2995 -- not needed if validity checks are off, and in subscript validity
2996 -- checking mode, all indexed components are checked with a call
2997 -- directly from Expand_N_Indexed_Component.
2999 if Comes_From_Source
(Call_Node
)
3000 and then Ekind
(Formal
) /= E_In_Parameter
3001 and then Validity_Checks_On
3002 and then Validity_Check_Default
3003 and then not Validity_Check_Subscripts
3005 Check_Valid_Lvalue_Subscripts
(Actual
);
3008 -- Mark any scalar OUT parameter that is a simple variable as no
3009 -- longer known to be valid (unless the type is always valid). This
3010 -- reflects the fact that if an OUT parameter is never set in a
3011 -- procedure, then it can become invalid on the procedure return.
3013 if Ekind
(Formal
) = E_Out_Parameter
3014 and then Is_Entity_Name
(Actual
)
3015 and then Ekind
(Entity
(Actual
)) = E_Variable
3016 and then not Is_Known_Valid
(Etype
(Actual
))
3018 Set_Is_Known_Valid
(Entity
(Actual
), False);
3021 -- For an OUT or IN OUT parameter, if the actual is an entity, then
3022 -- clear current values, since they can be clobbered. We are probably
3023 -- doing this in more places than we need to, but better safe than
3024 -- sorry when it comes to retaining bad current values!
3026 if Ekind
(Formal
) /= E_In_Parameter
3027 and then Is_Entity_Name
(Actual
)
3028 and then Present
(Entity
(Actual
))
3031 Ent
: constant Entity_Id
:= Entity
(Actual
);
3035 -- For an OUT or IN OUT parameter that is an assignable entity,
3036 -- we do not want to clobber the Last_Assignment field, since
3037 -- if it is set, it was precisely because it is indeed an OUT
3038 -- or IN OUT parameter! We do reset the Is_Known_Valid flag
3039 -- since the subprogram could have returned in invalid value.
3041 if Ekind_In
(Formal
, E_Out_Parameter
, E_In_Out_Parameter
)
3042 and then Is_Assignable
(Ent
)
3044 Sav
:= Last_Assignment
(Ent
);
3045 Kill_Current_Values
(Ent
);
3046 Set_Last_Assignment
(Ent
, Sav
);
3047 Set_Is_Known_Valid
(Ent
, False);
3049 -- For all other cases, just kill the current values
3052 Kill_Current_Values
(Ent
);
3057 -- If the formal is class wide and the actual is an aggregate, force
3058 -- evaluation so that the back end who does not know about class-wide
3059 -- type, does not generate a temporary of the wrong size.
3061 if not Is_Class_Wide_Type
(Etype
(Formal
)) then
3064 elsif Nkind
(Actual
) = N_Aggregate
3065 or else (Nkind
(Actual
) = N_Qualified_Expression
3066 and then Nkind
(Expression
(Actual
)) = N_Aggregate
)
3068 Force_Evaluation
(Actual
);
3071 -- In a remote call, if the formal is of a class-wide type, check
3072 -- that the actual meets the requirements described in E.4(18).
3074 if Remote
and then Is_Class_Wide_Type
(Etype
(Formal
)) then
3075 Insert_Action
(Actual
,
3076 Make_Transportable_Check
(Loc
,
3077 Duplicate_Subexpr_Move_Checks
(Actual
)));
3080 -- This label is required when skipping extra actual generation for
3081 -- Unchecked_Union parameters.
3083 <<Skip_Extra_Actual_Generation
>>
3085 Param_Count
:= Param_Count
+ 1;
3086 Next_Actual
(Actual
);
3087 Next_Formal
(Formal
);
3090 -- If we are calling an Ada 2012 function which needs to have the
3091 -- "accessibility level determined by the point of call" (AI05-0234)
3092 -- passed in to it, then pass it in.
3094 if Ekind_In
(Subp
, E_Function
, E_Operator
, E_Subprogram_Type
)
3096 Present
(Extra_Accessibility_Of_Result
(Ultimate_Alias
(Subp
)))
3099 Ancestor
: Node_Id
:= Parent
(Call_Node
);
3100 Level
: Node_Id
:= Empty
;
3101 Defer
: Boolean := False;
3104 -- Unimplemented: if Subp returns an anonymous access type, then
3106 -- a) if the call is the operand of an explict conversion, then
3107 -- the target type of the conversion (a named access type)
3108 -- determines the accessibility level pass in;
3110 -- b) if the call defines an access discriminant of an object
3111 -- (e.g., the discriminant of an object being created by an
3112 -- allocator, or the discriminant of a function result),
3113 -- then the accessibility level to pass in is that of the
3114 -- discriminated object being initialized).
3118 while Nkind
(Ancestor
) = N_Qualified_Expression
3120 Ancestor
:= Parent
(Ancestor
);
3123 case Nkind
(Ancestor
) is
3126 -- At this point, we'd like to assign
3128 -- Level := Dynamic_Accessibility_Level (Ancestor);
3130 -- but Etype of Ancestor may not have been set yet,
3131 -- so that doesn't work.
3133 -- Handle this later in Expand_Allocator_Expression.
3137 when N_Object_Declaration | N_Object_Renaming_Declaration
=>
3139 Def_Id
: constant Entity_Id
:=
3140 Defining_Identifier
(Ancestor
);
3143 if Is_Return_Object
(Def_Id
) then
3144 if Present
(Extra_Accessibility_Of_Result
3145 (Return_Applies_To
(Scope
(Def_Id
))))
3147 -- Pass along value that was passed in if the
3148 -- routine we are returning from also has an
3149 -- Accessibility_Of_Result formal.
3153 (Extra_Accessibility_Of_Result
3154 (Return_Applies_To
(Scope
(Def_Id
))), Loc
);
3158 Make_Integer_Literal
(Loc
,
3159 Intval
=> Object_Access_Level
(Def_Id
));
3163 when N_Simple_Return_Statement
=>
3164 if Present
(Extra_Accessibility_Of_Result
3166 (Return_Statement_Entity
(Ancestor
))))
3168 -- Pass along value that was passed in if the routine
3169 -- we are returning from also has an
3170 -- Accessibility_Of_Result formal.
3174 (Extra_Accessibility_Of_Result
3176 (Return_Statement_Entity
(Ancestor
))), Loc
);
3184 if not Present
(Level
) then
3186 -- The "innermost master that evaluates the function call".
3188 -- ??? - Should we use Integer'Last here instead in order
3189 -- to deal with (some of) the problems associated with
3190 -- calls to subps whose enclosing scope is unknown (e.g.,
3191 -- Anon_Access_To_Subp_Param.all)?
3193 Level
:= Make_Integer_Literal
(Loc
,
3194 Scope_Depth
(Current_Scope
) + 1);
3199 Extra_Accessibility_Of_Result
(Ultimate_Alias
(Subp
)));
3204 -- If we are expanding the RHS of an assignment we need to check if tag
3205 -- propagation is needed. You might expect this processing to be in
3206 -- Analyze_Assignment but has to be done earlier (bottom-up) because the
3207 -- assignment might be transformed to a declaration for an unconstrained
3208 -- value if the expression is classwide.
3210 if Nkind
(Call_Node
) = N_Function_Call
3211 and then Is_Tag_Indeterminate
(Call_Node
)
3212 and then Is_Entity_Name
(Name
(Call_Node
))
3215 Ass
: Node_Id
:= Empty
;
3218 if Nkind
(Parent
(Call_Node
)) = N_Assignment_Statement
then
3219 Ass
:= Parent
(Call_Node
);
3221 elsif Nkind
(Parent
(Call_Node
)) = N_Qualified_Expression
3222 and then Nkind
(Parent
(Parent
(Call_Node
))) =
3223 N_Assignment_Statement
3225 Ass
:= Parent
(Parent
(Call_Node
));
3227 elsif Nkind
(Parent
(Call_Node
)) = N_Explicit_Dereference
3228 and then Nkind
(Parent
(Parent
(Call_Node
))) =
3229 N_Assignment_Statement
3231 Ass
:= Parent
(Parent
(Call_Node
));
3235 and then Is_Class_Wide_Type
(Etype
(Name
(Ass
)))
3237 if Is_Access_Type
(Etype
(Call_Node
)) then
3238 if Designated_Type
(Etype
(Call_Node
)) /=
3239 Root_Type
(Etype
(Name
(Ass
)))
3242 ("tag-indeterminate expression "
3243 & " must have designated type& (RM 5.2 (6))",
3244 Call_Node
, Root_Type
(Etype
(Name
(Ass
))));
3246 Propagate_Tag
(Name
(Ass
), Call_Node
);
3249 elsif Etype
(Call_Node
) /= Root_Type
(Etype
(Name
(Ass
))) then
3251 ("tag-indeterminate expression must have type&"
3253 Call_Node
, Root_Type
(Etype
(Name
(Ass
))));
3256 Propagate_Tag
(Name
(Ass
), Call_Node
);
3259 -- The call will be rewritten as a dispatching call, and
3260 -- expanded as such.
3267 -- Ada 2005 (AI-251): If some formal is a class-wide interface, expand
3268 -- it to point to the correct secondary virtual table
3270 if Nkind
(Call_Node
) in N_Subprogram_Call
3271 and then CW_Interface_Formals_Present
3273 Expand_Interface_Actuals
(Call_Node
);
3276 -- Deals with Dispatch_Call if we still have a call, before expanding
3277 -- extra actuals since this will be done on the re-analysis of the
3278 -- dispatching call. Note that we do not try to shorten the actual list
3279 -- for a dispatching call, it would not make sense to do so. Expansion
3280 -- of dispatching calls is suppressed when VM_Target, because the VM
3281 -- back-ends directly handle the generation of dispatching calls and
3282 -- would have to undo any expansion to an indirect call.
3284 if Nkind
(Call_Node
) in N_Subprogram_Call
3285 and then Present
(Controlling_Argument
(Call_Node
))
3288 Call_Typ
: constant Entity_Id
:= Etype
(Call_Node
);
3289 Typ
: constant Entity_Id
:= Find_Dispatching_Type
(Subp
);
3290 Eq_Prim_Op
: Entity_Id
:= Empty
;
3293 Prev_Call
: Node_Id
;
3296 if not Is_Limited_Type
(Typ
) then
3297 Eq_Prim_Op
:= Find_Prim_Op
(Typ
, Name_Op_Eq
);
3300 if Tagged_Type_Expansion
then
3301 Expand_Dispatching_Call
(Call_Node
);
3303 -- The following return is worrisome. Is it really OK to skip
3304 -- all remaining processing in this procedure ???
3311 Apply_Tag_Checks
(Call_Node
);
3313 -- If this is a dispatching "=", we must first compare the
3314 -- tags so we generate: x.tag = y.tag and then x = y
3316 if Subp
= Eq_Prim_Op
then
3318 -- Mark the node as analyzed to avoid reanalizing this
3319 -- dispatching call (which would cause a never-ending loop)
3321 Prev_Call
:= Relocate_Node
(Call_Node
);
3322 Set_Analyzed
(Prev_Call
);
3324 Param
:= First_Actual
(Call_Node
);
3330 Make_Selected_Component
(Loc
,
3331 Prefix
=> New_Value
(Param
),
3333 New_Reference_To
(First_Tag_Component
(Typ
),
3337 Make_Selected_Component
(Loc
,
3339 Unchecked_Convert_To
(Typ
,
3340 New_Value
(Next_Actual
(Param
))),
3343 (First_Tag_Component
(Typ
), Loc
))),
3344 Right_Opnd
=> Prev_Call
);
3346 Rewrite
(Call_Node
, New_Call
);
3349 (Call_Node
, Call_Typ
, Suppress
=> All_Checks
);
3352 -- Expansion of a dispatching call results in an indirect call,
3353 -- which in turn causes current values to be killed (see
3354 -- Resolve_Call), so on VM targets we do the call here to
3355 -- ensure consistent warnings between VM and non-VM targets.
3357 Kill_Current_Values
;
3360 -- If this is a dispatching "=" then we must update the reference
3361 -- to the call node because we generated:
3362 -- x.tag = y.tag and then x = y
3364 if Subp
= Eq_Prim_Op
then
3365 Call_Node
:= Right_Opnd
(Call_Node
);
3370 -- Similarly, expand calls to RCI subprograms on which pragma
3371 -- All_Calls_Remote applies. The rewriting will be reanalyzed
3372 -- later. Do this only when the call comes from source since we
3373 -- do not want such a rewriting to occur in expanded code.
3375 if Is_All_Remote_Call
(Call_Node
) then
3376 Expand_All_Calls_Remote_Subprogram_Call
(Call_Node
);
3378 -- Similarly, do not add extra actuals for an entry call whose entity
3379 -- is a protected procedure, or for an internal protected subprogram
3380 -- call, because it will be rewritten as a protected subprogram call
3381 -- and reanalyzed (see Expand_Protected_Subprogram_Call).
3383 elsif Is_Protected_Type
(Scope
(Subp
))
3384 and then (Ekind
(Subp
) = E_Procedure
3385 or else Ekind
(Subp
) = E_Function
)
3389 -- During that loop we gathered the extra actuals (the ones that
3390 -- correspond to Extra_Formals), so now they can be appended.
3393 while Is_Non_Empty_List
(Extra_Actuals
) loop
3394 Add_Actual_Parameter
(Remove_Head
(Extra_Actuals
));
3398 -- At this point we have all the actuals, so this is the point at which
3399 -- the various expansion activities for actuals is carried out.
3401 Expand_Actuals
(Call_Node
, Subp
);
3403 -- Verify that the actuals do not share storage. This check must be done
3404 -- on the caller side rather that inside the subprogram to avoid issues
3405 -- of parameter passing.
3407 if Check_Aliasing_Of_Parameters
then
3408 Apply_Parameter_Aliasing_Checks
(Call_Node
, Subp
);
3411 -- If the subprogram is a renaming, or if it is inherited, replace it in
3412 -- the call with the name of the actual subprogram being called. If this
3413 -- is a dispatching call, the run-time decides what to call. The Alias
3414 -- attribute does not apply to entries.
3416 if Nkind
(Call_Node
) /= N_Entry_Call_Statement
3417 and then No
(Controlling_Argument
(Call_Node
))
3418 and then Present
(Parent_Subp
)
3419 and then not Is_Direct_Deep_Call
(Subp
)
3421 if Present
(Inherited_From_Formal
(Subp
)) then
3422 Parent_Subp
:= Inherited_From_Formal
(Subp
);
3424 Parent_Subp
:= Ultimate_Alias
(Parent_Subp
);
3427 -- The below setting of Entity is suspect, see F109-018 discussion???
3429 Set_Entity
(Name
(Call_Node
), Parent_Subp
);
3431 if Is_Abstract_Subprogram
(Parent_Subp
)
3432 and then not In_Instance
3435 ("cannot call abstract subprogram &!",
3436 Name
(Call_Node
), Parent_Subp
);
3439 -- Inspect all formals of derived subprogram Subp. Compare parameter
3440 -- types with the parent subprogram and check whether an actual may
3441 -- need a type conversion to the corresponding formal of the parent
3444 -- Not clear whether intrinsic subprograms need such conversions. ???
3446 if not Is_Intrinsic_Subprogram
(Parent_Subp
)
3447 or else Is_Generic_Instance
(Parent_Subp
)
3450 procedure Convert
(Act
: Node_Id
; Typ
: Entity_Id
);
3451 -- Rewrite node Act as a type conversion of Act to Typ. Analyze
3452 -- and resolve the newly generated construct.
3458 procedure Convert
(Act
: Node_Id
; Typ
: Entity_Id
) is
3460 Rewrite
(Act
, OK_Convert_To
(Typ
, Relocate_Node
(Act
)));
3467 Actual_Typ
: Entity_Id
;
3468 Formal_Typ
: Entity_Id
;
3469 Parent_Typ
: Entity_Id
;
3472 Actual
:= First_Actual
(Call_Node
);
3473 Formal
:= First_Formal
(Subp
);
3474 Parent_Formal
:= First_Formal
(Parent_Subp
);
3475 while Present
(Formal
) loop
3476 Actual_Typ
:= Etype
(Actual
);
3477 Formal_Typ
:= Etype
(Formal
);
3478 Parent_Typ
:= Etype
(Parent_Formal
);
3480 -- For an IN parameter of a scalar type, the parent formal
3481 -- type and derived formal type differ or the parent formal
3482 -- type and actual type do not match statically.
3484 if Is_Scalar_Type
(Formal_Typ
)
3485 and then Ekind
(Formal
) = E_In_Parameter
3486 and then Formal_Typ
/= Parent_Typ
3488 not Subtypes_Statically_Match
(Parent_Typ
, Actual_Typ
)
3489 and then not Raises_Constraint_Error
(Actual
)
3491 Convert
(Actual
, Parent_Typ
);
3492 Enable_Range_Check
(Actual
);
3494 -- If the actual has been marked as requiring a range
3495 -- check, then generate it here.
3497 if Do_Range_Check
(Actual
) then
3498 Set_Do_Range_Check
(Actual
, False);
3499 Generate_Range_Check
3500 (Actual
, Etype
(Formal
), CE_Range_Check_Failed
);
3503 -- For access types, the parent formal type and actual type
3506 elsif Is_Access_Type
(Formal_Typ
)
3507 and then Base_Type
(Parent_Typ
) /= Base_Type
(Actual_Typ
)
3509 if Ekind
(Formal
) /= E_In_Parameter
then
3510 Convert
(Actual
, Parent_Typ
);
3512 elsif Ekind
(Parent_Typ
) = E_Anonymous_Access_Type
3513 and then Designated_Type
(Parent_Typ
) /=
3514 Designated_Type
(Actual_Typ
)
3515 and then not Is_Controlling_Formal
(Formal
)
3517 -- This unchecked conversion is not necessary unless
3518 -- inlining is enabled, because in that case the type
3519 -- mismatch may become visible in the body about to be
3523 Unchecked_Convert_To
(Parent_Typ
,
3524 Relocate_Node
(Actual
)));
3526 Resolve
(Actual
, Parent_Typ
);
3529 -- For array and record types, the parent formal type and
3530 -- derived formal type have different sizes or pragma Pack
3533 elsif ((Is_Array_Type
(Formal_Typ
)
3534 and then Is_Array_Type
(Parent_Typ
))
3536 (Is_Record_Type
(Formal_Typ
)
3537 and then Is_Record_Type
(Parent_Typ
)))
3539 (Esize
(Formal_Typ
) /= Esize
(Parent_Typ
)
3540 or else Has_Pragma_Pack
(Formal_Typ
) /=
3541 Has_Pragma_Pack
(Parent_Typ
))
3543 Convert
(Actual
, Parent_Typ
);
3546 Next_Actual
(Actual
);
3547 Next_Formal
(Formal
);
3548 Next_Formal
(Parent_Formal
);
3554 Subp
:= Parent_Subp
;
3557 -- Check for violation of No_Abort_Statements
3559 if Restriction_Check_Required
(No_Abort_Statements
)
3560 and then Is_RTE
(Subp
, RE_Abort_Task
)
3562 Check_Restriction
(No_Abort_Statements
, Call_Node
);
3564 -- Check for violation of No_Dynamic_Attachment
3566 elsif Restriction_Check_Required
(No_Dynamic_Attachment
)
3567 and then RTU_Loaded
(Ada_Interrupts
)
3568 and then (Is_RTE
(Subp
, RE_Is_Reserved
) or else
3569 Is_RTE
(Subp
, RE_Is_Attached
) or else
3570 Is_RTE
(Subp
, RE_Current_Handler
) or else
3571 Is_RTE
(Subp
, RE_Attach_Handler
) or else
3572 Is_RTE
(Subp
, RE_Exchange_Handler
) or else
3573 Is_RTE
(Subp
, RE_Detach_Handler
) or else
3574 Is_RTE
(Subp
, RE_Reference
))
3576 Check_Restriction
(No_Dynamic_Attachment
, Call_Node
);
3579 -- Deal with case where call is an explicit dereference
3581 if Nkind
(Name
(Call_Node
)) = N_Explicit_Dereference
then
3583 -- Handle case of access to protected subprogram type
3585 if Is_Access_Protected_Subprogram_Type
3586 (Base_Type
(Etype
(Prefix
(Name
(Call_Node
)))))
3588 -- If this is a call through an access to protected operation, the
3589 -- prefix has the form (object'address, operation'access). Rewrite
3590 -- as a for other protected calls: the object is the 1st parameter
3591 -- of the list of actuals.
3598 Ptr
: constant Node_Id
:= Prefix
(Name
(Call_Node
));
3600 T
: constant Entity_Id
:=
3601 Equivalent_Type
(Base_Type
(Etype
(Ptr
)));
3603 D_T
: constant Entity_Id
:=
3604 Designated_Type
(Base_Type
(Etype
(Ptr
)));
3608 Make_Selected_Component
(Loc
,
3609 Prefix
=> Unchecked_Convert_To
(T
, Ptr
),
3611 New_Occurrence_Of
(First_Entity
(T
), Loc
));
3614 Make_Selected_Component
(Loc
,
3615 Prefix
=> Unchecked_Convert_To
(T
, Ptr
),
3617 New_Occurrence_Of
(Next_Entity
(First_Entity
(T
)), Loc
));
3620 Make_Explicit_Dereference
(Loc
,
3623 if Present
(Parameter_Associations
(Call_Node
)) then
3624 Parm
:= Parameter_Associations
(Call_Node
);
3629 Prepend
(Obj
, Parm
);
3631 if Etype
(D_T
) = Standard_Void_Type
then
3633 Make_Procedure_Call_Statement
(Loc
,
3635 Parameter_Associations
=> Parm
);
3638 Make_Function_Call
(Loc
,
3640 Parameter_Associations
=> Parm
);
3643 Set_First_Named_Actual
(Call
, First_Named_Actual
(Call_Node
));
3644 Set_Etype
(Call
, Etype
(D_T
));
3646 -- We do not re-analyze the call to avoid infinite recursion.
3647 -- We analyze separately the prefix and the object, and set
3648 -- the checks on the prefix that would otherwise be emitted
3649 -- when resolving a call.
3651 Rewrite
(Call_Node
, Call
);
3653 Apply_Access_Check
(Nam
);
3660 -- If this is a call to an intrinsic subprogram, then perform the
3661 -- appropriate expansion to the corresponding tree node and we
3662 -- are all done (since after that the call is gone!)
3664 -- In the case where the intrinsic is to be processed by the back end,
3665 -- the call to Expand_Intrinsic_Call will do nothing, which is fine,
3666 -- since the idea in this case is to pass the call unchanged. If the
3667 -- intrinsic is an inherited unchecked conversion, and the derived type
3668 -- is the target type of the conversion, we must retain it as the return
3669 -- type of the expression. Otherwise the expansion below, which uses the
3670 -- parent operation, will yield the wrong type.
3672 if Is_Intrinsic_Subprogram
(Subp
) then
3673 Expand_Intrinsic_Call
(Call_Node
, Subp
);
3675 if Nkind
(Call_Node
) = N_Unchecked_Type_Conversion
3676 and then Parent_Subp
/= Orig_Subp
3677 and then Etype
(Parent_Subp
) /= Etype
(Orig_Subp
)
3679 Set_Etype
(Call_Node
, Etype
(Orig_Subp
));
3685 if Ekind_In
(Subp
, E_Function
, E_Procedure
) then
3687 -- We perform two simple optimization on calls:
3689 -- a) replace calls to null procedures unconditionally;
3691 -- b) for To_Address, just do an unchecked conversion. Not only is
3692 -- this efficient, but it also avoids order of elaboration problems
3693 -- when address clauses are inlined (address expression elaborated
3694 -- at the wrong point).
3696 -- We perform these optimization regardless of whether we are in the
3697 -- main unit or in a unit in the context of the main unit, to ensure
3698 -- that tree generated is the same in both cases, for Inspector use.
3700 if Is_RTE
(Subp
, RE_To_Address
) then
3702 Unchecked_Convert_To
3703 (RTE
(RE_Address
), Relocate_Node
(First_Actual
(Call_Node
))));
3706 elsif Is_Null_Procedure
(Subp
) then
3707 Rewrite
(Call_Node
, Make_Null_Statement
(Loc
));
3711 -- Handle inlining (old semantics)
3713 if Is_Inlined
(Subp
) and then not Debug_Flag_Dot_K
then
3714 Inlined_Subprogram
: declare
3716 Must_Inline
: Boolean := False;
3717 Spec
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
3720 -- Verify that the body to inline has already been seen, and
3721 -- that if the body is in the current unit the inlining does
3722 -- not occur earlier. This avoids order-of-elaboration problems
3725 -- This should be documented in sinfo/einfo ???
3728 or else Nkind
(Spec
) /= N_Subprogram_Declaration
3729 or else No
(Body_To_Inline
(Spec
))
3731 Must_Inline
:= False;
3733 -- If this an inherited function that returns a private type,
3734 -- do not inline if the full view is an unconstrained array,
3735 -- because such calls cannot be inlined.
3737 elsif Present
(Orig_Subp
)
3738 and then Is_Array_Type
(Etype
(Orig_Subp
))
3739 and then not Is_Constrained
(Etype
(Orig_Subp
))
3741 Must_Inline
:= False;
3743 elsif In_Unfrozen_Instance
(Scope
(Subp
)) then
3744 Must_Inline
:= False;
3747 Bod
:= Body_To_Inline
(Spec
);
3749 if (In_Extended_Main_Code_Unit
(Call_Node
)
3750 or else In_Extended_Main_Code_Unit
(Parent
(Call_Node
))
3751 or else Has_Pragma_Inline_Always
(Subp
))
3752 and then (not In_Same_Extended_Unit
(Sloc
(Bod
), Loc
)
3754 Earlier_In_Extended_Unit
(Sloc
(Bod
), Loc
))
3756 Must_Inline
:= True;
3758 -- If we are compiling a package body that is not the main
3759 -- unit, it must be for inlining/instantiation purposes,
3760 -- in which case we inline the call to insure that the same
3761 -- temporaries are generated when compiling the body by
3762 -- itself. Otherwise link errors can occur.
3764 -- If the function being called is itself in the main unit,
3765 -- we cannot inline, because there is a risk of double
3766 -- elaboration and/or circularity: the inlining can make
3767 -- visible a private entity in the body of the main unit,
3768 -- that gigi will see before its sees its proper definition.
3770 elsif not (In_Extended_Main_Code_Unit
(Call_Node
))
3771 and then In_Package_Body
3773 Must_Inline
:= not In_Extended_Main_Source_Unit
(Subp
);
3778 Expand_Inlined_Call
(Call_Node
, Subp
, Orig_Subp
);
3781 -- Let the back end handle it
3783 Add_Inlined_Body
(Subp
);
3785 if Front_End_Inlining
3786 and then Nkind
(Spec
) = N_Subprogram_Declaration
3787 and then (In_Extended_Main_Code_Unit
(Call_Node
))
3788 and then No
(Body_To_Inline
(Spec
))
3789 and then not Has_Completion
(Subp
)
3790 and then In_Same_Extended_Unit
(Sloc
(Spec
), Loc
)
3793 ("cannot inline& (body not seen yet)?",
3797 end Inlined_Subprogram
;
3799 -- Handle inlining (new semantics)
3801 elsif Is_Inlined
(Subp
) then
3803 Spec
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
3806 if Must_Inline
(Subp
) then
3807 if In_Extended_Main_Code_Unit
(Call_Node
)
3808 and then In_Same_Extended_Unit
(Sloc
(Spec
), Loc
)
3809 and then not Has_Completion
(Subp
)
3812 ("cannot inline& (body not seen yet)?",
3816 Do_Inline_Always
(Subp
, Orig_Subp
);
3819 elsif Optimization_Level
> 0 then
3820 Do_Inline
(Subp
, Orig_Subp
);
3823 -- The call may have been inlined or may have been passed to
3824 -- the backend. No further action needed if it was inlined.
3826 if Nkind
(N
) /= N_Function_Call
then
3833 -- Check for protected subprogram. This is either an intra-object call,
3834 -- or a protected function call. Protected procedure calls are rewritten
3835 -- as entry calls and handled accordingly.
3837 -- In Ada 2005, this may be an indirect call to an access parameter that
3838 -- is an access_to_subprogram. In that case the anonymous type has a
3839 -- scope that is a protected operation, but the call is a regular one.
3840 -- In either case do not expand call if subprogram is eliminated.
3842 Scop
:= Scope
(Subp
);
3844 if Nkind
(Call_Node
) /= N_Entry_Call_Statement
3845 and then Is_Protected_Type
(Scop
)
3846 and then Ekind
(Subp
) /= E_Subprogram_Type
3847 and then not Is_Eliminated
(Subp
)
3849 -- If the call is an internal one, it is rewritten as a call to the
3850 -- corresponding unprotected subprogram.
3852 Expand_Protected_Subprogram_Call
(Call_Node
, Subp
, Scop
);
3855 -- Functions returning controlled objects need special attention. If
3856 -- the return type is limited, then the context is initialization and
3857 -- different processing applies. If the call is to a protected function,
3858 -- the expansion above will call Expand_Call recursively. Otherwise the
3859 -- function call is transformed into a temporary which obtains the
3860 -- result from the secondary stack.
3862 if Needs_Finalization
(Etype
(Subp
)) then
3863 if not Is_Immutably_Limited_Type
(Etype
(Subp
))
3865 (No
(First_Formal
(Subp
))
3867 not Is_Concurrent_Record_Type
(Etype
(First_Formal
(Subp
))))
3869 Expand_Ctrl_Function_Call
(Call_Node
);
3871 -- Build-in-place function calls which appear in anonymous contexts
3872 -- need a transient scope to ensure the proper finalization of the
3873 -- intermediate result after its use.
3875 elsif Is_Build_In_Place_Function_Call
(Call_Node
)
3877 Nkind_In
(Parent
(Call_Node
), N_Attribute_Reference
,
3879 N_Indexed_Component
,
3880 N_Object_Renaming_Declaration
,
3881 N_Procedure_Call_Statement
,
3882 N_Selected_Component
,
3885 Establish_Transient_Scope
(Call_Node
, Sec_Stack
=> True);
3889 -- Test for First_Optional_Parameter, and if so, truncate parameter list
3890 -- if there are optional parameters at the trailing end.
3891 -- Note: we never delete procedures for call via a pointer.
3893 if (Ekind
(Subp
) = E_Procedure
or else Ekind
(Subp
) = E_Function
)
3894 and then Present
(First_Optional_Parameter
(Subp
))
3897 Last_Keep_Arg
: Node_Id
;
3900 -- Last_Keep_Arg will hold the last actual that should be kept.
3901 -- If it remains empty at the end, it means that all parameters
3904 Last_Keep_Arg
:= Empty
;
3906 -- Find first optional parameter, must be present since we checked
3907 -- the validity of the parameter before setting it.
3909 Formal
:= First_Formal
(Subp
);
3910 Actual
:= First_Actual
(Call_Node
);
3911 while Formal
/= First_Optional_Parameter
(Subp
) loop
3912 Last_Keep_Arg
:= Actual
;
3913 Next_Formal
(Formal
);
3914 Next_Actual
(Actual
);
3917 -- We have Formal and Actual pointing to the first potentially
3918 -- droppable argument. We can drop all the trailing arguments
3919 -- whose actual matches the default. Note that we know that all
3920 -- remaining formals have defaults, because we checked that this
3921 -- requirement was met before setting First_Optional_Parameter.
3923 -- We use Fully_Conformant_Expressions to check for identity
3924 -- between formals and actuals, which may miss some cases, but
3925 -- on the other hand, this is only an optimization (if we fail
3926 -- to truncate a parameter it does not affect functionality).
3927 -- So if the default is 3 and the actual is 1+2, we consider
3928 -- them unequal, which hardly seems worrisome.
3930 while Present
(Formal
) loop
3931 if not Fully_Conformant_Expressions
3932 (Actual
, Default_Value
(Formal
))
3934 Last_Keep_Arg
:= Actual
;
3937 Next_Formal
(Formal
);
3938 Next_Actual
(Actual
);
3941 -- If no arguments, delete entire list, this is the easy case
3943 if No
(Last_Keep_Arg
) then
3944 Set_Parameter_Associations
(Call_Node
, No_List
);
3945 Set_First_Named_Actual
(Call_Node
, Empty
);
3947 -- Case where at the last retained argument is positional. This
3948 -- is also an easy case, since the retained arguments are already
3949 -- in the right form, and we don't need to worry about the order
3950 -- of arguments that get eliminated.
3952 elsif Is_List_Member
(Last_Keep_Arg
) then
3953 while Present
(Next
(Last_Keep_Arg
)) loop
3954 Discard_Node
(Remove_Next
(Last_Keep_Arg
));
3957 Set_First_Named_Actual
(Call_Node
, Empty
);
3959 -- This is the annoying case where the last retained argument
3960 -- is a named parameter. Since the original arguments are not
3961 -- in declaration order, we may have to delete some fairly
3962 -- random collection of arguments.
3970 -- First step, remove all the named parameters from the
3971 -- list (they are still chained using First_Named_Actual
3972 -- and Next_Named_Actual, so we have not lost them!)
3974 Temp
:= First
(Parameter_Associations
(Call_Node
));
3976 -- Case of all parameters named, remove them all
3978 if Nkind
(Temp
) = N_Parameter_Association
then
3979 -- Suppress warnings to avoid warning on possible
3980 -- infinite loop (because Call_Node is not modified).
3982 pragma Warnings
(Off
);
3983 while Is_Non_Empty_List
3984 (Parameter_Associations
(Call_Node
))
3987 Remove_Head
(Parameter_Associations
(Call_Node
));
3989 pragma Warnings
(On
);
3991 -- Case of mixed positional/named, remove named parameters
3994 while Nkind
(Next
(Temp
)) /= N_Parameter_Association
loop
3998 while Present
(Next
(Temp
)) loop
3999 Remove
(Next
(Temp
));
4003 -- Now we loop through the named parameters, till we get
4004 -- to the last one to be retained, adding them to the list.
4005 -- Note that the Next_Named_Actual list does not need to be
4006 -- touched since we are only reordering them on the actual
4007 -- parameter association list.
4009 Passoc
:= Parent
(First_Named_Actual
(Call_Node
));
4011 Temp
:= Relocate_Node
(Passoc
);
4013 (Parameter_Associations
(Call_Node
), Temp
);
4015 Last_Keep_Arg
= Explicit_Actual_Parameter
(Passoc
);
4016 Passoc
:= Parent
(Next_Named_Actual
(Passoc
));
4019 Set_Next_Named_Actual
(Temp
, Empty
);
4022 Temp
:= Next_Named_Actual
(Passoc
);
4023 exit when No
(Temp
);
4024 Set_Next_Named_Actual
4025 (Passoc
, Next_Named_Actual
(Parent
(Temp
)));
4034 -------------------------------
4035 -- Expand_Ctrl_Function_Call --
4036 -------------------------------
4038 procedure Expand_Ctrl_Function_Call
(N
: Node_Id
) is
4039 function Enclosing_Context
return Node_Id
;
4040 -- Find the enclosing context where the function call appears
4042 -----------------------
4043 -- Enclosing_Context --
4044 -----------------------
4046 function Enclosing_Context
return Node_Id
is
4050 Context
:= Parent
(N
);
4051 while Present
(Context
) loop
4053 -- The following could use a comment (and why is N_Case_Expression
4054 -- not treated in a similar manner ???
4056 if Nkind
(Context
) = N_If_Expression
then
4059 -- Stop the search when reaching any statement because we have
4060 -- gone too far up the tree.
4062 elsif Nkind
(Context
) = N_Procedure_Call_Statement
4063 or else Nkind
(Context
) in N_Statement_Other_Than_Procedure_Call
4068 Context
:= Parent
(Context
);
4072 end Enclosing_Context
;
4076 Context
: constant Node_Id
:= Enclosing_Context
;
4079 -- Optimization, if the returned value (which is on the sec-stack) is
4080 -- returned again, no need to copy/readjust/finalize, we can just pass
4081 -- the value thru (see Expand_N_Simple_Return_Statement), and thus no
4082 -- attachment is needed
4084 if Nkind
(Parent
(N
)) = N_Simple_Return_Statement
then
4088 -- Resolution is now finished, make sure we don't start analysis again
4089 -- because of the duplication.
4093 -- A function which returns a controlled object uses the secondary
4094 -- stack. Rewrite the call into a temporary which obtains the result of
4095 -- the function using 'reference.
4097 Remove_Side_Effects
(N
);
4099 -- The function call is part of an if expression dependent expression.
4100 -- The temporary result must live as long as the if expression itself,
4101 -- otherwise it will be finalized too early. Mark the transient as
4102 -- processed to avoid untimely finalization.
4104 -- Why no special handling for case expressions here ???
4106 if Present
(Context
)
4107 and then Nkind
(Context
) = N_If_Expression
4108 and then Nkind
(N
) = N_Explicit_Dereference
4110 Set_Is_Processed_Transient
(Entity
(Prefix
(N
)));
4112 end Expand_Ctrl_Function_Call
;
4114 -------------------------
4115 -- Expand_Inlined_Call --
4116 -------------------------
4118 procedure Expand_Inlined_Call
4121 Orig_Subp
: Entity_Id
)
4123 Loc
: constant Source_Ptr
:= Sloc
(N
);
4124 Is_Predef
: constant Boolean :=
4125 Is_Predefined_File_Name
4126 (Unit_File_Name
(Get_Source_Unit
(Subp
)));
4127 Orig_Bod
: constant Node_Id
:=
4128 Body_To_Inline
(Unit_Declaration_Node
(Subp
));
4132 Decls
: constant List_Id
:= New_List
;
4133 Exit_Lab
: Entity_Id
:= Empty
;
4140 Ret_Type
: Entity_Id
;
4143 -- The target of the call. If context is an assignment statement then
4144 -- this is the left-hand side of the assignment, else it is a temporary
4145 -- to which the return value is assigned prior to rewriting the call.
4148 -- A separate target used when the return type is unconstrained
4151 Temp_Typ
: Entity_Id
;
4153 Return_Object
: Entity_Id
:= Empty
;
4154 -- Entity in declaration in an extended_return_statement
4157 Is_Unc_Decl
: Boolean;
4158 -- If the type returned by the function is unconstrained and the call
4159 -- can be inlined, special processing is required.
4161 procedure Make_Exit_Label
;
4162 -- Build declaration for exit label to be used in Return statements,
4163 -- sets Exit_Lab (the label node) and Lab_Decl (corresponding implicit
4164 -- declaration). Does nothing if Exit_Lab already set.
4166 function Process_Formals
(N
: Node_Id
) return Traverse_Result
;
4167 -- Replace occurrence of a formal with the corresponding actual, or the
4168 -- thunk generated for it.
4170 function Process_Sloc
(Nod
: Node_Id
) return Traverse_Result
;
4171 -- If the call being expanded is that of an internal subprogram, set the
4172 -- sloc of the generated block to that of the call itself, so that the
4173 -- expansion is skipped by the "next" command in gdb.
4174 -- Same processing for a subprogram in a predefined file, e.g.
4175 -- Ada.Tags. If Debug_Generated_Code is true, suppress this change to
4176 -- simplify our own development.
4178 procedure Reset_Dispatching_Calls
(N
: Node_Id
);
4179 -- In subtree N search for occurrences of dispatching calls that use the
4180 -- Ada 2005 Object.Operation notation and the object is a formal of the
4181 -- inlined subprogram. Reset the entity associated with Operation in all
4182 -- the found occurrences.
4184 procedure Rewrite_Function_Call
(N
: Node_Id
; Blk
: Node_Id
);
4185 -- If the function body is a single expression, replace call with
4186 -- expression, else insert block appropriately.
4188 procedure Rewrite_Procedure_Call
(N
: Node_Id
; Blk
: Node_Id
);
4189 -- If procedure body has no local variables, inline body without
4190 -- creating block, otherwise rewrite call with block.
4192 function Formal_Is_Used_Once
(Formal
: Entity_Id
) return Boolean;
4193 -- Determine whether a formal parameter is used only once in Orig_Bod
4195 ---------------------
4196 -- Make_Exit_Label --
4197 ---------------------
4199 procedure Make_Exit_Label
is
4200 Lab_Ent
: Entity_Id
;
4202 if No
(Exit_Lab
) then
4203 Lab_Ent
:= Make_Temporary
(Loc
, 'L');
4204 Lab_Id
:= New_Reference_To
(Lab_Ent
, Loc
);
4205 Exit_Lab
:= Make_Label
(Loc
, Lab_Id
);
4207 Make_Implicit_Label_Declaration
(Loc
,
4208 Defining_Identifier
=> Lab_Ent
,
4209 Label_Construct
=> Exit_Lab
);
4211 end Make_Exit_Label
;
4213 ---------------------
4214 -- Process_Formals --
4215 ---------------------
4217 function Process_Formals
(N
: Node_Id
) return Traverse_Result
is
4223 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
4227 and then Scope
(E
) = Subp
4229 A
:= Renamed_Object
(E
);
4231 -- Rewrite the occurrence of the formal into an occurrence of
4232 -- the actual. Also establish visibility on the proper view of
4233 -- the actual's subtype for the body's context (if the actual's
4234 -- subtype is private at the call point but its full view is
4235 -- visible to the body, then the inlined tree here must be
4236 -- analyzed with the full view).
4238 if Is_Entity_Name
(A
) then
4239 Rewrite
(N
, New_Occurrence_Of
(Entity
(A
), Loc
));
4240 Check_Private_View
(N
);
4242 elsif Nkind
(A
) = N_Defining_Identifier
then
4243 Rewrite
(N
, New_Occurrence_Of
(A
, Loc
));
4244 Check_Private_View
(N
);
4249 Rewrite
(N
, New_Copy
(A
));
4255 elsif Is_Entity_Name
(N
)
4256 and then Present
(Return_Object
)
4257 and then Chars
(N
) = Chars
(Return_Object
)
4259 -- Occurrence within an extended return statement. The return
4260 -- object is local to the body been inlined, and thus the generic
4261 -- copy is not analyzed yet, so we match by name, and replace it
4262 -- with target of call.
4264 if Nkind
(Targ
) = N_Defining_Identifier
then
4265 Rewrite
(N
, New_Occurrence_Of
(Targ
, Loc
));
4267 Rewrite
(N
, New_Copy_Tree
(Targ
));
4272 elsif Nkind
(N
) = N_Simple_Return_Statement
then
4273 if No
(Expression
(N
)) then
4276 Make_Goto_Statement
(Loc
, Name
=> New_Copy
(Lab_Id
)));
4279 if Nkind
(Parent
(N
)) = N_Handled_Sequence_Of_Statements
4280 and then Nkind
(Parent
(Parent
(N
))) = N_Subprogram_Body
4282 -- Function body is a single expression. No need for
4288 Num_Ret
:= Num_Ret
+ 1;
4292 -- Because of the presence of private types, the views of the
4293 -- expression and the context may be different, so place an
4294 -- unchecked conversion to the context type to avoid spurious
4295 -- errors, e.g. when the expression is a numeric literal and
4296 -- the context is private. If the expression is an aggregate,
4297 -- use a qualified expression, because an aggregate is not a
4298 -- legal argument of a conversion.
4300 if Nkind_In
(Expression
(N
), N_Aggregate
, N_Null
) then
4302 Make_Qualified_Expression
(Sloc
(N
),
4303 Subtype_Mark
=> New_Occurrence_Of
(Ret_Type
, Sloc
(N
)),
4304 Expression
=> Relocate_Node
(Expression
(N
)));
4307 Unchecked_Convert_To
4308 (Ret_Type
, Relocate_Node
(Expression
(N
)));
4311 if Nkind
(Targ
) = N_Defining_Identifier
then
4313 Make_Assignment_Statement
(Loc
,
4314 Name
=> New_Occurrence_Of
(Targ
, Loc
),
4315 Expression
=> Ret
));
4318 Make_Assignment_Statement
(Loc
,
4319 Name
=> New_Copy
(Targ
),
4320 Expression
=> Ret
));
4323 Set_Assignment_OK
(Name
(N
));
4325 if Present
(Exit_Lab
) then
4327 Make_Goto_Statement
(Loc
, Name
=> New_Copy
(Lab_Id
)));
4333 -- An extended return becomes a block whose first statement is the
4334 -- assignment of the initial expression of the return object to the
4335 -- target of the call itself.
4337 elsif Nkind
(N
) = N_Extended_Return_Statement
then
4339 Return_Decl
: constant Entity_Id
:=
4340 First
(Return_Object_Declarations
(N
));
4344 Return_Object
:= Defining_Identifier
(Return_Decl
);
4346 if Present
(Expression
(Return_Decl
)) then
4347 if Nkind
(Targ
) = N_Defining_Identifier
then
4349 Make_Assignment_Statement
(Loc
,
4350 Name
=> New_Occurrence_Of
(Targ
, Loc
),
4351 Expression
=> Expression
(Return_Decl
));
4354 Make_Assignment_Statement
(Loc
,
4355 Name
=> New_Copy
(Targ
),
4356 Expression
=> Expression
(Return_Decl
));
4359 Set_Assignment_OK
(Name
(Assign
));
4361 if No
(Handled_Statement_Sequence
(N
)) then
4362 Set_Handled_Statement_Sequence
(N
,
4363 Make_Handled_Sequence_Of_Statements
(Loc
,
4364 Statements
=> New_List
));
4368 Statements
(Handled_Statement_Sequence
(N
)));
4372 Make_Block_Statement
(Loc
,
4373 Handled_Statement_Sequence
=>
4374 Handled_Statement_Sequence
(N
)));
4379 -- Remove pragma Unreferenced since it may refer to formals that
4380 -- are not visible in the inlined body, and in any case we will
4381 -- not be posting warnings on the inlined body so it is unneeded.
4383 elsif Nkind
(N
) = N_Pragma
4384 and then Pragma_Name
(N
) = Name_Unreferenced
4386 Rewrite
(N
, Make_Null_Statement
(Sloc
(N
)));
4392 end Process_Formals
;
4394 procedure Replace_Formals
is new Traverse_Proc
(Process_Formals
);
4400 function Process_Sloc
(Nod
: Node_Id
) return Traverse_Result
is
4402 if not Debug_Generated_Code
then
4403 Set_Sloc
(Nod
, Sloc
(N
));
4404 Set_Comes_From_Source
(Nod
, False);
4410 procedure Reset_Slocs
is new Traverse_Proc
(Process_Sloc
);
4412 ------------------------------
4413 -- Reset_Dispatching_Calls --
4414 ------------------------------
4416 procedure Reset_Dispatching_Calls
(N
: Node_Id
) is
4418 function Do_Reset
(N
: Node_Id
) return Traverse_Result
;
4419 -- Comment required ???
4425 function Do_Reset
(N
: Node_Id
) return Traverse_Result
is
4427 if Nkind
(N
) = N_Procedure_Call_Statement
4428 and then Nkind
(Name
(N
)) = N_Selected_Component
4429 and then Nkind
(Prefix
(Name
(N
))) = N_Identifier
4430 and then Is_Formal
(Entity
(Prefix
(Name
(N
))))
4431 and then Is_Dispatching_Operation
4432 (Entity
(Selector_Name
(Name
(N
))))
4434 Set_Entity
(Selector_Name
(Name
(N
)), Empty
);
4440 function Do_Reset_Calls
is new Traverse_Func
(Do_Reset
);
4444 Dummy
: constant Traverse_Result
:= Do_Reset_Calls
(N
);
4445 pragma Unreferenced
(Dummy
);
4447 -- Start of processing for Reset_Dispatching_Calls
4451 end Reset_Dispatching_Calls
;
4453 ---------------------------
4454 -- Rewrite_Function_Call --
4455 ---------------------------
4457 procedure Rewrite_Function_Call
(N
: Node_Id
; Blk
: Node_Id
) is
4458 HSS
: constant Node_Id
:= Handled_Statement_Sequence
(Blk
);
4459 Fst
: constant Node_Id
:= First
(Statements
(HSS
));
4462 -- Optimize simple case: function body is a single return statement,
4463 -- which has been expanded into an assignment.
4465 if Is_Empty_List
(Declarations
(Blk
))
4466 and then Nkind
(Fst
) = N_Assignment_Statement
4467 and then No
(Next
(Fst
))
4469 -- The function call may have been rewritten as the temporary
4470 -- that holds the result of the call, in which case remove the
4471 -- now useless declaration.
4473 if Nkind
(N
) = N_Identifier
4474 and then Nkind
(Parent
(Entity
(N
))) = N_Object_Declaration
4476 Rewrite
(Parent
(Entity
(N
)), Make_Null_Statement
(Loc
));
4479 Rewrite
(N
, Expression
(Fst
));
4481 elsif Nkind
(N
) = N_Identifier
4482 and then Nkind
(Parent
(Entity
(N
))) = N_Object_Declaration
4484 -- The block assigns the result of the call to the temporary
4486 Insert_After
(Parent
(Entity
(N
)), Blk
);
4488 -- If the context is an assignment, and the left-hand side is free of
4489 -- side-effects, the replacement is also safe.
4490 -- Can this be generalized further???
4492 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
4494 (Is_Entity_Name
(Name
(Parent
(N
)))
4496 (Nkind
(Name
(Parent
(N
))) = N_Explicit_Dereference
4497 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
)))))
4500 (Nkind
(Name
(Parent
(N
))) = N_Selected_Component
4501 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
))))))
4503 -- Replace assignment with the block
4506 Original_Assignment
: constant Node_Id
:= Parent
(N
);
4509 -- Preserve the original assignment node to keep the complete
4510 -- assignment subtree consistent enough for Analyze_Assignment
4511 -- to proceed (specifically, the original Lhs node must still
4512 -- have an assignment statement as its parent).
4514 -- We cannot rely on Original_Node to go back from the block
4515 -- node to the assignment node, because the assignment might
4516 -- already be a rewrite substitution.
4518 Discard_Node
(Relocate_Node
(Original_Assignment
));
4519 Rewrite
(Original_Assignment
, Blk
);
4522 elsif Nkind
(Parent
(N
)) = N_Object_Declaration
then
4524 -- A call to a function which returns an unconstrained type
4525 -- found in the expression initializing an object-declaration is
4526 -- expanded into a procedure call which must be added after the
4527 -- object declaration.
4529 if Is_Unc_Decl
and then Debug_Flag_Dot_K
then
4530 Insert_Action_After
(Parent
(N
), Blk
);
4532 Set_Expression
(Parent
(N
), Empty
);
4533 Insert_After
(Parent
(N
), Blk
);
4536 elsif Is_Unc
and then not Debug_Flag_Dot_K
then
4537 Insert_Before
(Parent
(N
), Blk
);
4539 end Rewrite_Function_Call
;
4541 ----------------------------
4542 -- Rewrite_Procedure_Call --
4543 ----------------------------
4545 procedure Rewrite_Procedure_Call
(N
: Node_Id
; Blk
: Node_Id
) is
4546 HSS
: constant Node_Id
:= Handled_Statement_Sequence
(Blk
);
4549 -- If there is a transient scope for N, this will be the scope of the
4550 -- actions for N, and the statements in Blk need to be within this
4551 -- scope. For example, they need to have visibility on the constant
4552 -- declarations created for the formals.
4554 -- If N needs no transient scope, and if there are no declarations in
4555 -- the inlined body, we can do a little optimization and insert the
4556 -- statements for the body directly after N, and rewrite N to a
4557 -- null statement, instead of rewriting N into a full-blown block
4560 if not Scope_Is_Transient
4561 and then Is_Empty_List
(Declarations
(Blk
))
4563 Insert_List_After
(N
, Statements
(HSS
));
4564 Rewrite
(N
, Make_Null_Statement
(Loc
));
4568 end Rewrite_Procedure_Call
;
4570 -------------------------
4571 -- Formal_Is_Used_Once --
4572 -------------------------
4574 function Formal_Is_Used_Once
(Formal
: Entity_Id
) return Boolean is
4575 Use_Counter
: Int
:= 0;
4577 function Count_Uses
(N
: Node_Id
) return Traverse_Result
;
4578 -- Traverse the tree and count the uses of the formal parameter.
4579 -- In this case, for optimization purposes, we do not need to
4580 -- continue the traversal once more than one use is encountered.
4586 function Count_Uses
(N
: Node_Id
) return Traverse_Result
is
4588 -- The original node is an identifier
4590 if Nkind
(N
) = N_Identifier
4591 and then Present
(Entity
(N
))
4593 -- Original node's entity points to the one in the copied body
4595 and then Nkind
(Entity
(N
)) = N_Identifier
4596 and then Present
(Entity
(Entity
(N
)))
4598 -- The entity of the copied node is the formal parameter
4600 and then Entity
(Entity
(N
)) = Formal
4602 Use_Counter
:= Use_Counter
+ 1;
4604 if Use_Counter
> 1 then
4606 -- Denote more than one use and abandon the traversal
4617 procedure Count_Formal_Uses
is new Traverse_Proc
(Count_Uses
);
4619 -- Start of processing for Formal_Is_Used_Once
4622 Count_Formal_Uses
(Orig_Bod
);
4623 return Use_Counter
= 1;
4624 end Formal_Is_Used_Once
;
4626 -- Start of processing for Expand_Inlined_Call
4629 -- Initializations for old/new semantics
4631 if not Debug_Flag_Dot_K
then
4632 Is_Unc
:= Is_Array_Type
(Etype
(Subp
))
4633 and then not Is_Constrained
(Etype
(Subp
));
4634 Is_Unc_Decl
:= False;
4636 Is_Unc
:= Returns_Unconstrained_Type
(Subp
)
4637 and then Optimization_Level
> 0;
4638 Is_Unc_Decl
:= Nkind
(Parent
(N
)) = N_Object_Declaration
4642 -- Check for an illegal attempt to inline a recursive procedure. If the
4643 -- subprogram has parameters this is detected when trying to supply a
4644 -- binding for parameters that already have one. For parameterless
4645 -- subprograms this must be done explicitly.
4647 if In_Open_Scopes
(Subp
) then
4648 Error_Msg_N
("call to recursive subprogram cannot be inlined??", N
);
4649 Set_Is_Inlined
(Subp
, False);
4652 -- Skip inlining if this is not a true inlining since the attribute
4653 -- Body_To_Inline is also set for renamings (see sinfo.ads)
4655 elsif Nkind
(Orig_Bod
) in N_Entity
then
4658 -- Skip inlining if the function returns an unconstrained type using
4659 -- an extended return statement since this part of the new inlining
4660 -- model which is not yet supported by the current implementation. ???
4664 Nkind
(First
(Statements
(Handled_Statement_Sequence
(Orig_Bod
))))
4665 = N_Extended_Return_Statement
4666 and then not Debug_Flag_Dot_K
4671 if Nkind
(Orig_Bod
) = N_Defining_Identifier
4672 or else Nkind
(Orig_Bod
) = N_Defining_Operator_Symbol
4674 -- Subprogram is renaming_as_body. Calls occurring after the renaming
4675 -- can be replaced with calls to the renamed entity directly, because
4676 -- the subprograms are subtype conformant. If the renamed subprogram
4677 -- is an inherited operation, we must redo the expansion because
4678 -- implicit conversions may be needed. Similarly, if the renamed
4679 -- entity is inlined, expand the call for further optimizations.
4681 Set_Name
(N
, New_Occurrence_Of
(Orig_Bod
, Loc
));
4683 if Present
(Alias
(Orig_Bod
)) or else Is_Inlined
(Orig_Bod
) then
4690 -- Register the call in the list of inlined calls
4692 if Inlined_Calls
= No_Elist
then
4693 Inlined_Calls
:= New_Elmt_List
;
4696 Append_Elmt
(N
, To
=> Inlined_Calls
);
4698 -- Use generic machinery to copy body of inlined subprogram, as if it
4699 -- were an instantiation, resetting source locations appropriately, so
4700 -- that nested inlined calls appear in the main unit.
4702 Save_Env
(Subp
, Empty
);
4703 Set_Copied_Sloc_For_Inlined_Body
(N
, Defining_Entity
(Orig_Bod
));
4707 if not Debug_Flag_Dot_K
then
4712 Bod
:= Copy_Generic_Node
(Orig_Bod
, Empty
, Instantiating
=> True);
4714 Make_Block_Statement
(Loc
,
4715 Declarations
=> Declarations
(Bod
),
4716 Handled_Statement_Sequence
=>
4717 Handled_Statement_Sequence
(Bod
));
4719 if No
(Declarations
(Bod
)) then
4720 Set_Declarations
(Blk
, New_List
);
4723 -- For the unconstrained case, capture the name of the local
4724 -- variable that holds the result. This must be the first
4725 -- declaration in the block, because its bounds cannot depend
4726 -- on local variables. Otherwise there is no way to declare the
4727 -- result outside of the block. Needless to say, in general the
4728 -- bounds will depend on the actuals in the call.
4730 -- If the context is an assignment statement, as is the case
4731 -- for the expansion of an extended return, the left-hand side
4732 -- provides bounds even if the return type is unconstrained.
4736 First_Decl
: Node_Id
;
4739 First_Decl
:= First
(Declarations
(Blk
));
4741 if Nkind
(First_Decl
) /= N_Object_Declaration
then
4745 if Nkind
(Parent
(N
)) /= N_Assignment_Statement
then
4746 Targ1
:= Defining_Identifier
(First_Decl
);
4748 Targ1
:= Name
(Parent
(N
));
4765 Copy_Generic_Node
(Orig_Bod
, Empty
, Instantiating
=> True);
4767 Make_Block_Statement
(Loc
,
4768 Declarations
=> Declarations
(Bod
),
4769 Handled_Statement_Sequence
=>
4770 Handled_Statement_Sequence
(Bod
));
4772 -- Inline a call to a function that returns an unconstrained type.
4773 -- The semantic analyzer checked that frontend-inlined functions
4774 -- returning unconstrained types have no declarations and have
4775 -- a single extended return statement. As part of its processing
4776 -- the function was split in two subprograms: a procedure P and
4777 -- a function F that has a block with a call to procedure P (see
4778 -- Split_Unconstrained_Function).
4784 (Statements
(Handled_Statement_Sequence
(Orig_Bod
))))
4785 = N_Block_Statement
);
4788 Blk_Stmt
: constant Node_Id
:=
4791 (Handled_Statement_Sequence
(Orig_Bod
)));
4792 First_Stmt
: constant Node_Id
:=
4795 (Handled_Statement_Sequence
(Blk_Stmt
)));
4796 Second_Stmt
: constant Node_Id
:= Next
(First_Stmt
);
4800 (Nkind
(First_Stmt
) = N_Procedure_Call_Statement
4801 and then Nkind
(Second_Stmt
) = N_Simple_Return_Statement
4802 and then No
(Next
(Second_Stmt
)));
4807 (Statements
(Handled_Statement_Sequence
(Orig_Bod
))),
4808 Empty
, Instantiating
=> True);
4811 -- Capture the name of the local variable that holds the
4812 -- result. This must be the first declaration in the block,
4813 -- because its bounds cannot depend on local variables.
4814 -- Otherwise there is no way to declare the result outside
4815 -- of the block. Needless to say, in general the bounds will
4816 -- depend on the actuals in the call.
4818 if Nkind
(Parent
(N
)) /= N_Assignment_Statement
then
4819 Targ1
:= Defining_Identifier
(First
(Declarations
(Blk
)));
4821 -- If the context is an assignment statement, as is the case
4822 -- for the expansion of an extended return, the left-hand
4823 -- side provides bounds even if the return type is
4827 Targ1
:= Name
(Parent
(N
));
4832 if No
(Declarations
(Bod
)) then
4833 Set_Declarations
(Blk
, New_List
);
4838 -- If this is a derived function, establish the proper return type
4840 if Present
(Orig_Subp
) and then Orig_Subp
/= Subp
then
4841 Ret_Type
:= Etype
(Orig_Subp
);
4843 Ret_Type
:= Etype
(Subp
);
4846 -- Create temporaries for the actuals that are expressions, or that are
4847 -- scalars and require copying to preserve semantics.
4849 F
:= First_Formal
(Subp
);
4850 A
:= First_Actual
(N
);
4851 while Present
(F
) loop
4852 if Present
(Renamed_Object
(F
)) then
4853 Error_Msg_N
("cannot inline call to recursive subprogram", N
);
4857 -- Reset Last_Assignment for any parameters of mode out or in out, to
4858 -- prevent spurious warnings about overwriting for assignments to the
4859 -- formal in the inlined code.
4861 if Is_Entity_Name
(A
) and then Ekind
(F
) /= E_In_Parameter
then
4862 Set_Last_Assignment
(Entity
(A
), Empty
);
4865 -- If the argument may be a controlling argument in a call within
4866 -- the inlined body, we must preserve its classwide nature to insure
4867 -- that dynamic dispatching take place subsequently. If the formal
4868 -- has a constraint it must be preserved to retain the semantics of
4871 if Is_Class_Wide_Type
(Etype
(F
))
4872 or else (Is_Access_Type
(Etype
(F
))
4873 and then Is_Class_Wide_Type
(Designated_Type
(Etype
(F
))))
4875 Temp_Typ
:= Etype
(F
);
4877 elsif Base_Type
(Etype
(F
)) = Base_Type
(Etype
(A
))
4878 and then Etype
(F
) /= Base_Type
(Etype
(F
))
4880 Temp_Typ
:= Etype
(F
);
4882 Temp_Typ
:= Etype
(A
);
4885 -- If the actual is a simple name or a literal, no need to
4886 -- create a temporary, object can be used directly.
4888 -- If the actual is a literal and the formal has its address taken,
4889 -- we cannot pass the literal itself as an argument, so its value
4890 -- must be captured in a temporary.
4892 if (Is_Entity_Name
(A
)
4894 (not Is_Scalar_Type
(Etype
(A
))
4895 or else Ekind
(Entity
(A
)) = E_Enumeration_Literal
))
4897 -- When the actual is an identifier and the corresponding formal is
4898 -- used only once in the original body, the formal can be substituted
4899 -- directly with the actual parameter.
4901 or else (Nkind
(A
) = N_Identifier
4902 and then Formal_Is_Used_Once
(F
))
4905 (Nkind_In
(A
, N_Real_Literal
,
4907 N_Character_Literal
)
4908 and then not Address_Taken
(F
))
4910 if Etype
(F
) /= Etype
(A
) then
4912 (F
, Unchecked_Convert_To
(Etype
(F
), Relocate_Node
(A
)));
4914 Set_Renamed_Object
(F
, A
);
4918 Temp
:= Make_Temporary
(Loc
, 'C');
4920 -- If the actual for an in/in-out parameter is a view conversion,
4921 -- make it into an unchecked conversion, given that an untagged
4922 -- type conversion is not a proper object for a renaming.
4924 -- In-out conversions that involve real conversions have already
4925 -- been transformed in Expand_Actuals.
4927 if Nkind
(A
) = N_Type_Conversion
4928 and then Ekind
(F
) /= E_In_Parameter
4931 Make_Unchecked_Type_Conversion
(Loc
,
4932 Subtype_Mark
=> New_Occurrence_Of
(Etype
(F
), Loc
),
4933 Expression
=> Relocate_Node
(Expression
(A
)));
4935 elsif Etype
(F
) /= Etype
(A
) then
4936 New_A
:= Unchecked_Convert_To
(Etype
(F
), Relocate_Node
(A
));
4937 Temp_Typ
:= Etype
(F
);
4940 New_A
:= Relocate_Node
(A
);
4943 Set_Sloc
(New_A
, Sloc
(N
));
4945 -- If the actual has a by-reference type, it cannot be copied,
4946 -- so its value is captured in a renaming declaration. Otherwise
4947 -- declare a local constant initialized with the actual.
4949 -- We also use a renaming declaration for expressions of an array
4950 -- type that is not bit-packed, both for efficiency reasons and to
4951 -- respect the semantics of the call: in most cases the original
4952 -- call will pass the parameter by reference, and thus the inlined
4953 -- code will have the same semantics.
4955 if Ekind
(F
) = E_In_Parameter
4956 and then not Is_By_Reference_Type
(Etype
(A
))
4958 (not Is_Array_Type
(Etype
(A
))
4959 or else not Is_Object_Reference
(A
)
4960 or else Is_Bit_Packed_Array
(Etype
(A
)))
4963 Make_Object_Declaration
(Loc
,
4964 Defining_Identifier
=> Temp
,
4965 Constant_Present
=> True,
4966 Object_Definition
=> New_Occurrence_Of
(Temp_Typ
, Loc
),
4967 Expression
=> New_A
);
4970 Make_Object_Renaming_Declaration
(Loc
,
4971 Defining_Identifier
=> Temp
,
4972 Subtype_Mark
=> New_Occurrence_Of
(Temp_Typ
, Loc
),
4976 Append
(Decl
, Decls
);
4977 Set_Renamed_Object
(F
, Temp
);
4984 -- Establish target of function call. If context is not assignment or
4985 -- declaration, create a temporary as a target. The declaration for the
4986 -- temporary may be subsequently optimized away if the body is a single
4987 -- expression, or if the left-hand side of the assignment is simple
4988 -- enough, i.e. an entity or an explicit dereference of one.
4990 if Ekind
(Subp
) = E_Function
then
4991 if Nkind
(Parent
(N
)) = N_Assignment_Statement
4992 and then Is_Entity_Name
(Name
(Parent
(N
)))
4994 Targ
:= Name
(Parent
(N
));
4996 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
4997 and then Nkind
(Name
(Parent
(N
))) = N_Explicit_Dereference
4998 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
))))
5000 Targ
:= Name
(Parent
(N
));
5002 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
5003 and then Nkind
(Name
(Parent
(N
))) = N_Selected_Component
5004 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
))))
5006 Targ
:= New_Copy_Tree
(Name
(Parent
(N
)));
5008 elsif Nkind
(Parent
(N
)) = N_Object_Declaration
5009 and then Is_Limited_Type
(Etype
(Subp
))
5011 Targ
:= Defining_Identifier
(Parent
(N
));
5013 -- New semantics: In an object declaration avoid an extra copy
5014 -- of the result of a call to an inlined function that returns
5015 -- an unconstrained type
5017 elsif Debug_Flag_Dot_K
5018 and then Nkind
(Parent
(N
)) = N_Object_Declaration
5021 Targ
:= Defining_Identifier
(Parent
(N
));
5024 -- Replace call with temporary and create its declaration
5026 Temp
:= Make_Temporary
(Loc
, 'C');
5027 Set_Is_Internal
(Temp
);
5029 -- For the unconstrained case, the generated temporary has the
5030 -- same constrained declaration as the result variable. It may
5031 -- eventually be possible to remove that temporary and use the
5032 -- result variable directly.
5035 and then Nkind
(Parent
(N
)) /= N_Assignment_Statement
5038 Make_Object_Declaration
(Loc
,
5039 Defining_Identifier
=> Temp
,
5040 Object_Definition
=>
5041 New_Copy_Tree
(Object_Definition
(Parent
(Targ1
))));
5043 Replace_Formals
(Decl
);
5047 Make_Object_Declaration
(Loc
,
5048 Defining_Identifier
=> Temp
,
5049 Object_Definition
=> New_Occurrence_Of
(Ret_Type
, Loc
));
5051 Set_Etype
(Temp
, Ret_Type
);
5054 Set_No_Initialization
(Decl
);
5055 Append
(Decl
, Decls
);
5056 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
5061 Insert_Actions
(N
, Decls
);
5065 -- Special management for inlining a call to a function that returns
5066 -- an unconstrained type and initializes an object declaration: we
5067 -- avoid generating undesired extra calls and goto statements.
5070 -- function Func (...) return ...
5073 -- Result : String (1 .. 4);
5075 -- Proc (Result, ...);
5080 -- Result : String := Func (...);
5082 -- Replace this object declaration by:
5084 -- Result : String (1 .. 4);
5085 -- Proc (Result, ...);
5087 Remove_Homonym
(Targ
);
5090 Make_Object_Declaration
5092 Defining_Identifier
=> Targ
,
5093 Object_Definition
=>
5094 New_Copy_Tree
(Object_Definition
(Parent
(Targ1
))));
5095 Replace_Formals
(Decl
);
5096 Rewrite
(Parent
(N
), Decl
);
5097 Analyze
(Parent
(N
));
5099 -- Avoid spurious warnings since we know that this declaration is
5100 -- referenced by the procedure call.
5102 Set_Never_Set_In_Source
(Targ
, False);
5104 -- Remove the local declaration of the extended return stmt from the
5107 Remove
(Parent
(Targ1
));
5109 -- Update the reference to the result (since we have rewriten the
5110 -- object declaration)
5113 Blk_Call_Stmt
: Node_Id
;
5116 -- Capture the call to the procedure
5119 First
(Statements
(Handled_Statement_Sequence
(Blk
)));
5121 (Nkind
(Blk_Call_Stmt
) = N_Procedure_Call_Statement
);
5123 Remove
(First
(Parameter_Associations
(Blk_Call_Stmt
)));
5124 Prepend_To
(Parameter_Associations
(Blk_Call_Stmt
),
5125 New_Reference_To
(Targ
, Loc
));
5128 -- Remove the return statement
5131 (Nkind
(Last
(Statements
(Handled_Statement_Sequence
(Blk
)))) =
5132 N_Simple_Return_Statement
);
5134 Remove
(Last
(Statements
(Handled_Statement_Sequence
(Blk
))));
5137 -- Traverse the tree and replace formals with actuals or their thunks.
5138 -- Attach block to tree before analysis and rewriting.
5140 Replace_Formals
(Blk
);
5141 Set_Parent
(Blk
, N
);
5143 if not Comes_From_Source
(Subp
) or else Is_Predef
then
5149 -- No action needed since return statement has been already removed!
5153 elsif Present
(Exit_Lab
) then
5155 -- If the body was a single expression, the single return statement
5156 -- and the corresponding label are useless.
5160 Nkind
(Last
(Statements
(Handled_Statement_Sequence
(Blk
)))) =
5163 Remove
(Last
(Statements
(Handled_Statement_Sequence
(Blk
))));
5165 Append
(Lab_Decl
, (Declarations
(Blk
)));
5166 Append
(Exit_Lab
, Statements
(Handled_Statement_Sequence
(Blk
)));
5170 -- Analyze Blk with In_Inlined_Body set, to avoid spurious errors
5171 -- on conflicting private views that Gigi would ignore. If this is a
5172 -- predefined unit, analyze with checks off, as is done in the non-
5173 -- inlined run-time units.
5176 I_Flag
: constant Boolean := In_Inlined_Body
;
5179 In_Inlined_Body
:= True;
5183 Style
: constant Boolean := Style_Check
;
5186 Style_Check
:= False;
5188 -- Search for dispatching calls that use the Object.Operation
5189 -- notation using an Object that is a parameter of the inlined
5190 -- function. We reset the decoration of Operation to force
5191 -- the reanalysis of the inlined dispatching call because
5192 -- the actual object has been inlined.
5194 Reset_Dispatching_Calls
(Blk
);
5196 Analyze
(Blk
, Suppress
=> All_Checks
);
5197 Style_Check
:= Style
;
5204 In_Inlined_Body
:= I_Flag
;
5207 if Ekind
(Subp
) = E_Procedure
then
5208 Rewrite_Procedure_Call
(N
, Blk
);
5211 Rewrite_Function_Call
(N
, Blk
);
5216 -- For the unconstrained case, the replacement of the call has been
5217 -- made prior to the complete analysis of the generated declarations.
5218 -- Propagate the proper type now.
5221 if Nkind
(N
) = N_Identifier
then
5222 Set_Etype
(N
, Etype
(Entity
(N
)));
5224 Set_Etype
(N
, Etype
(Targ1
));
5231 -- Cleanup mapping between formals and actuals for other expansions
5233 F
:= First_Formal
(Subp
);
5234 while Present
(F
) loop
5235 Set_Renamed_Object
(F
, Empty
);
5238 end Expand_Inlined_Call
;
5240 ----------------------------------------
5241 -- Expand_N_Extended_Return_Statement --
5242 ----------------------------------------
5244 -- If there is a Handled_Statement_Sequence, we rewrite this:
5246 -- return Result : T := <expression> do
5247 -- <handled_seq_of_stms>
5253 -- Result : T := <expression>;
5255 -- <handled_seq_of_stms>
5259 -- Otherwise (no Handled_Statement_Sequence), we rewrite this:
5261 -- return Result : T := <expression>;
5265 -- return <expression>;
5267 -- unless it's build-in-place or there's no <expression>, in which case
5271 -- Result : T := <expression>;
5276 -- Note that this case could have been written by the user as an extended
5277 -- return statement, or could have been transformed to this from a simple
5278 -- return statement.
5280 -- That is, we need to have a reified return object if there are statements
5281 -- (which might refer to it) or if we're doing build-in-place (so we can
5282 -- set its address to the final resting place or if there is no expression
5283 -- (in which case default initial values might need to be set).
5285 procedure Expand_N_Extended_Return_Statement
(N
: Node_Id
) is
5286 Loc
: constant Source_Ptr
:= Sloc
(N
);
5288 Par_Func
: constant Entity_Id
:=
5289 Return_Applies_To
(Return_Statement_Entity
(N
));
5290 Result_Subt
: constant Entity_Id
:= Etype
(Par_Func
);
5291 Ret_Obj_Id
: constant Entity_Id
:=
5292 First_Entity
(Return_Statement_Entity
(N
));
5293 Ret_Obj_Decl
: constant Node_Id
:= Parent
(Ret_Obj_Id
);
5295 Is_Build_In_Place
: constant Boolean :=
5296 Is_Build_In_Place_Function
(Par_Func
);
5301 Return_Stmt
: Node_Id
;
5304 function Build_Heap_Allocator
5305 (Temp_Id
: Entity_Id
;
5306 Temp_Typ
: Entity_Id
;
5307 Func_Id
: Entity_Id
;
5308 Ret_Typ
: Entity_Id
;
5309 Alloc_Expr
: Node_Id
) return Node_Id
;
5310 -- Create the statements necessary to allocate a return object on the
5311 -- caller's master. The master is available through implicit parameter
5312 -- BIPfinalizationmaster.
5314 -- if BIPfinalizationmaster /= null then
5316 -- type Ptr_Typ is access Ret_Typ;
5317 -- for Ptr_Typ'Storage_Pool use
5318 -- Base_Pool (BIPfinalizationmaster.all).all;
5322 -- procedure Allocate (...) is
5324 -- System.Storage_Pools.Subpools.Allocate_Any (...);
5327 -- Local := <Alloc_Expr>;
5328 -- Temp_Id := Temp_Typ (Local);
5332 -- Temp_Id is the temporary which is used to reference the internally
5333 -- created object in all allocation forms. Temp_Typ is the type of the
5334 -- temporary. Func_Id is the enclosing function. Ret_Typ is the return
5335 -- type of Func_Id. Alloc_Expr is the actual allocator.
5337 function Move_Activation_Chain
return Node_Id
;
5338 -- Construct a call to System.Tasking.Stages.Move_Activation_Chain
5340 -- From current activation chain
5341 -- To activation chain passed in by the caller
5342 -- New_Master master passed in by the caller
5344 --------------------------
5345 -- Build_Heap_Allocator --
5346 --------------------------
5348 function Build_Heap_Allocator
5349 (Temp_Id
: Entity_Id
;
5350 Temp_Typ
: Entity_Id
;
5351 Func_Id
: Entity_Id
;
5352 Ret_Typ
: Entity_Id
;
5353 Alloc_Expr
: Node_Id
) return Node_Id
5356 pragma Assert
(Is_Build_In_Place_Function
(Func_Id
));
5358 -- Processing for build-in-place object allocation. This is disabled
5359 -- on .NET/JVM because the targets do not support pools.
5361 if VM_Target
= No_VM
5362 and then Needs_Finalization
(Ret_Typ
)
5365 Decls
: constant List_Id
:= New_List
;
5366 Fin_Mas_Id
: constant Entity_Id
:=
5367 Build_In_Place_Formal
5368 (Func_Id
, BIP_Finalization_Master
);
5369 Stmts
: constant List_Id
:= New_List
;
5370 Desig_Typ
: Entity_Id
;
5371 Local_Id
: Entity_Id
;
5372 Pool_Id
: Entity_Id
;
5373 Ptr_Typ
: Entity_Id
;
5377 -- Pool_Id renames Base_Pool (BIPfinalizationmaster.all).all;
5379 Pool_Id
:= Make_Temporary
(Loc
, 'P');
5382 Make_Object_Renaming_Declaration
(Loc
,
5383 Defining_Identifier
=> Pool_Id
,
5385 New_Reference_To
(RTE
(RE_Root_Storage_Pool
), Loc
),
5387 Make_Explicit_Dereference
(Loc
,
5389 Make_Function_Call
(Loc
,
5391 New_Reference_To
(RTE
(RE_Base_Pool
), Loc
),
5392 Parameter_Associations
=> New_List
(
5393 Make_Explicit_Dereference
(Loc
,
5395 New_Reference_To
(Fin_Mas_Id
, Loc
)))))));
5397 -- Create an access type which uses the storage pool of the
5398 -- caller's master. This additional type is necessary because
5399 -- the finalization master cannot be associated with the type
5400 -- of the temporary. Otherwise the secondary stack allocation
5403 Desig_Typ
:= Ret_Typ
;
5405 -- Ensure that the build-in-place machinery uses a fat pointer
5406 -- when allocating an unconstrained array on the heap. In this
5407 -- case the result object type is a constrained array type even
5408 -- though the function type is unconstrained.
5410 if Ekind
(Desig_Typ
) = E_Array_Subtype
then
5411 Desig_Typ
:= Base_Type
(Desig_Typ
);
5415 -- type Ptr_Typ is access Desig_Typ;
5417 Ptr_Typ
:= Make_Temporary
(Loc
, 'P');
5420 Make_Full_Type_Declaration
(Loc
,
5421 Defining_Identifier
=> Ptr_Typ
,
5423 Make_Access_To_Object_Definition
(Loc
,
5424 Subtype_Indication
=>
5425 New_Reference_To
(Desig_Typ
, Loc
))));
5427 -- Perform minor decoration in order to set the master and the
5428 -- storage pool attributes.
5430 Set_Ekind
(Ptr_Typ
, E_Access_Type
);
5431 Set_Finalization_Master
(Ptr_Typ
, Fin_Mas_Id
);
5432 Set_Associated_Storage_Pool
(Ptr_Typ
, Pool_Id
);
5434 -- Create the temporary, generate:
5435 -- Local_Id : Ptr_Typ;
5437 Local_Id
:= Make_Temporary
(Loc
, 'T');
5440 Make_Object_Declaration
(Loc
,
5441 Defining_Identifier
=> Local_Id
,
5442 Object_Definition
=>
5443 New_Reference_To
(Ptr_Typ
, Loc
)));
5445 -- Allocate the object, generate:
5446 -- Local_Id := <Alloc_Expr>;
5449 Make_Assignment_Statement
(Loc
,
5450 Name
=> New_Reference_To
(Local_Id
, Loc
),
5451 Expression
=> Alloc_Expr
));
5454 -- Temp_Id := Temp_Typ (Local_Id);
5457 Make_Assignment_Statement
(Loc
,
5458 Name
=> New_Reference_To
(Temp_Id
, Loc
),
5460 Unchecked_Convert_To
(Temp_Typ
,
5461 New_Reference_To
(Local_Id
, Loc
))));
5463 -- Wrap the allocation in a block. This is further conditioned
5464 -- by checking the caller finalization master at runtime. A
5465 -- null value indicates a non-existent master, most likely due
5466 -- to a Finalize_Storage_Only allocation.
5469 -- if BIPfinalizationmaster /= null then
5478 Make_If_Statement
(Loc
,
5481 Left_Opnd
=> New_Reference_To
(Fin_Mas_Id
, Loc
),
5482 Right_Opnd
=> Make_Null
(Loc
)),
5484 Then_Statements
=> New_List
(
5485 Make_Block_Statement
(Loc
,
5486 Declarations
=> Decls
,
5487 Handled_Statement_Sequence
=>
5488 Make_Handled_Sequence_Of_Statements
(Loc
,
5489 Statements
=> Stmts
))));
5492 -- For all other cases, generate:
5493 -- Temp_Id := <Alloc_Expr>;
5497 Make_Assignment_Statement
(Loc
,
5498 Name
=> New_Reference_To
(Temp_Id
, Loc
),
5499 Expression
=> Alloc_Expr
);
5501 end Build_Heap_Allocator
;
5503 ---------------------------
5504 -- Move_Activation_Chain --
5505 ---------------------------
5507 function Move_Activation_Chain
return Node_Id
is
5510 Make_Procedure_Call_Statement
(Loc
,
5512 New_Reference_To
(RTE
(RE_Move_Activation_Chain
), Loc
),
5514 Parameter_Associations
=> New_List
(
5518 Make_Attribute_Reference
(Loc
,
5519 Prefix
=> Make_Identifier
(Loc
, Name_uChain
),
5520 Attribute_Name
=> Name_Unrestricted_Access
),
5522 -- Destination chain
5525 (Build_In_Place_Formal
(Par_Func
, BIP_Activation_Chain
), Loc
),
5530 (Build_In_Place_Formal
(Par_Func
, BIP_Task_Master
), Loc
)));
5531 end Move_Activation_Chain
;
5533 -- Start of processing for Expand_N_Extended_Return_Statement
5536 if Nkind
(Ret_Obj_Decl
) = N_Object_Declaration
then
5537 Exp
:= Expression
(Ret_Obj_Decl
);
5542 HSS
:= Handled_Statement_Sequence
(N
);
5544 -- If the returned object needs finalization actions, the function must
5545 -- perform the appropriate cleanup should it fail to return. The state
5546 -- of the function itself is tracked through a flag which is coupled
5547 -- with the scope finalizer. There is one flag per each return object
5548 -- in case of multiple returns.
5550 if Is_Build_In_Place
5551 and then Needs_Finalization
(Etype
(Ret_Obj_Id
))
5554 Flag_Decl
: Node_Id
;
5555 Flag_Id
: Entity_Id
;
5559 -- Recover the function body
5561 Func_Bod
:= Unit_Declaration_Node
(Par_Func
);
5563 if Nkind
(Func_Bod
) = N_Subprogram_Declaration
then
5564 Func_Bod
:= Parent
(Parent
(Corresponding_Body
(Func_Bod
)));
5567 -- Create a flag to track the function state
5569 Flag_Id
:= Make_Temporary
(Loc
, 'F');
5570 Set_Status_Flag_Or_Transient_Decl
(Ret_Obj_Id
, Flag_Id
);
5572 -- Insert the flag at the beginning of the function declarations,
5574 -- Fnn : Boolean := False;
5577 Make_Object_Declaration
(Loc
,
5578 Defining_Identifier
=> Flag_Id
,
5579 Object_Definition
=>
5580 New_Reference_To
(Standard_Boolean
, Loc
),
5581 Expression
=> New_Reference_To
(Standard_False
, Loc
));
5583 Prepend_To
(Declarations
(Func_Bod
), Flag_Decl
);
5584 Analyze
(Flag_Decl
);
5588 -- Build a simple_return_statement that returns the return object when
5589 -- there is a statement sequence, or no expression, or the result will
5590 -- be built in place. Note however that we currently do this for all
5591 -- composite cases, even though nonlimited composite results are not yet
5592 -- built in place (though we plan to do so eventually).
5595 or else Is_Composite_Type
(Result_Subt
)
5601 -- If the extended return has a handled statement sequence, then wrap
5602 -- it in a block and use the block as the first statement.
5606 Make_Block_Statement
(Loc
,
5607 Declarations
=> New_List
,
5608 Handled_Statement_Sequence
=> HSS
));
5611 -- If the result type contains tasks, we call Move_Activation_Chain.
5612 -- Later, the cleanup code will call Complete_Master, which will
5613 -- terminate any unactivated tasks belonging to the return statement
5614 -- master. But Move_Activation_Chain updates their master to be that
5615 -- of the caller, so they will not be terminated unless the return
5616 -- statement completes unsuccessfully due to exception, abort, goto,
5617 -- or exit. As a formality, we test whether the function requires the
5618 -- result to be built in place, though that's necessarily true for
5619 -- the case of result types with task parts.
5621 if Is_Build_In_Place
5622 and then Has_Task
(Result_Subt
)
5624 -- The return expression is an aggregate for a complex type which
5625 -- contains tasks. This particular case is left unexpanded since
5626 -- the regular expansion would insert all temporaries and
5627 -- initialization code in the wrong block.
5629 if Nkind
(Exp
) = N_Aggregate
then
5630 Expand_N_Aggregate
(Exp
);
5633 -- Do not move the activation chain if the return object does not
5636 if Has_Task
(Etype
(Ret_Obj_Id
)) then
5637 Append_To
(Stmts
, Move_Activation_Chain
);
5641 -- Update the state of the function right before the object is
5644 if Is_Build_In_Place
5645 and then Needs_Finalization
(Etype
(Ret_Obj_Id
))
5648 Flag_Id
: constant Entity_Id
:=
5649 Status_Flag_Or_Transient_Decl
(Ret_Obj_Id
);
5656 Make_Assignment_Statement
(Loc
,
5657 Name
=> New_Reference_To
(Flag_Id
, Loc
),
5658 Expression
=> New_Reference_To
(Standard_True
, Loc
)));
5662 -- Build a simple_return_statement that returns the return object
5665 Make_Simple_Return_Statement
(Loc
,
5666 Expression
=> New_Occurrence_Of
(Ret_Obj_Id
, Loc
));
5667 Append_To
(Stmts
, Return_Stmt
);
5669 HSS
:= Make_Handled_Sequence_Of_Statements
(Loc
, Stmts
);
5672 -- Case where we build a return statement block
5674 if Present
(HSS
) then
5676 Make_Block_Statement
(Loc
,
5677 Declarations
=> Return_Object_Declarations
(N
),
5678 Handled_Statement_Sequence
=> HSS
);
5680 -- We set the entity of the new block statement to be that of the
5681 -- return statement. This is necessary so that various fields, such
5682 -- as Finalization_Chain_Entity carry over from the return statement
5683 -- to the block. Note that this block is unusual, in that its entity
5684 -- is an E_Return_Statement rather than an E_Block.
5687 (Result
, New_Occurrence_Of
(Return_Statement_Entity
(N
), Loc
));
5689 -- If the object decl was already rewritten as a renaming, then we
5690 -- don't want to do the object allocation and transformation of of
5691 -- the return object declaration to a renaming. This case occurs
5692 -- when the return object is initialized by a call to another
5693 -- build-in-place function, and that function is responsible for
5694 -- the allocation of the return object.
5696 if Is_Build_In_Place
5697 and then Nkind
(Ret_Obj_Decl
) = N_Object_Renaming_Declaration
5700 (Nkind
(Original_Node
(Ret_Obj_Decl
)) = N_Object_Declaration
5701 and then Is_Build_In_Place_Function_Call
5702 (Expression
(Original_Node
(Ret_Obj_Decl
))));
5704 -- Return the build-in-place result by reference
5706 Set_By_Ref
(Return_Stmt
);
5708 elsif Is_Build_In_Place
then
5710 -- Locate the implicit access parameter associated with the
5711 -- caller-supplied return object and convert the return
5712 -- statement's return object declaration to a renaming of a
5713 -- dereference of the access parameter. If the return object's
5714 -- declaration includes an expression that has not already been
5715 -- expanded as separate assignments, then add an assignment
5716 -- statement to ensure the return object gets initialized.
5719 -- Result : T [:= <expression>];
5726 -- Result : T renames FuncRA.all;
5727 -- [Result := <expression;]
5732 Return_Obj_Id
: constant Entity_Id
:=
5733 Defining_Identifier
(Ret_Obj_Decl
);
5734 Return_Obj_Typ
: constant Entity_Id
:= Etype
(Return_Obj_Id
);
5735 Return_Obj_Expr
: constant Node_Id
:=
5736 Expression
(Ret_Obj_Decl
);
5737 Constr_Result
: constant Boolean :=
5738 Is_Constrained
(Result_Subt
);
5739 Obj_Alloc_Formal
: Entity_Id
;
5740 Object_Access
: Entity_Id
;
5741 Obj_Acc_Deref
: Node_Id
;
5742 Init_Assignment
: Node_Id
:= Empty
;
5745 -- Build-in-place results must be returned by reference
5747 Set_By_Ref
(Return_Stmt
);
5749 -- Retrieve the implicit access parameter passed by the caller
5752 Build_In_Place_Formal
(Par_Func
, BIP_Object_Access
);
5754 -- If the return object's declaration includes an expression
5755 -- and the declaration isn't marked as No_Initialization, then
5756 -- we need to generate an assignment to the object and insert
5757 -- it after the declaration before rewriting it as a renaming
5758 -- (otherwise we'll lose the initialization). The case where
5759 -- the result type is an interface (or class-wide interface)
5760 -- is also excluded because the context of the function call
5761 -- must be unconstrained, so the initialization will always
5762 -- be done as part of an allocator evaluation (storage pool
5763 -- or secondary stack), never to a constrained target object
5764 -- passed in by the caller. Besides the assignment being
5765 -- unneeded in this case, it avoids problems with trying to
5766 -- generate a dispatching assignment when the return expression
5767 -- is a nonlimited descendant of a limited interface (the
5768 -- interface has no assignment operation).
5770 if Present
(Return_Obj_Expr
)
5771 and then not No_Initialization
(Ret_Obj_Decl
)
5772 and then not Is_Interface
(Return_Obj_Typ
)
5775 Make_Assignment_Statement
(Loc
,
5776 Name
=> New_Reference_To
(Return_Obj_Id
, Loc
),
5777 Expression
=> Relocate_Node
(Return_Obj_Expr
));
5779 Set_Etype
(Name
(Init_Assignment
), Etype
(Return_Obj_Id
));
5780 Set_Assignment_OK
(Name
(Init_Assignment
));
5781 Set_No_Ctrl_Actions
(Init_Assignment
);
5783 Set_Parent
(Name
(Init_Assignment
), Init_Assignment
);
5784 Set_Parent
(Expression
(Init_Assignment
), Init_Assignment
);
5786 Set_Expression
(Ret_Obj_Decl
, Empty
);
5788 if Is_Class_Wide_Type
(Etype
(Return_Obj_Id
))
5789 and then not Is_Class_Wide_Type
5790 (Etype
(Expression
(Init_Assignment
)))
5792 Rewrite
(Expression
(Init_Assignment
),
5793 Make_Type_Conversion
(Loc
,
5795 New_Occurrence_Of
(Etype
(Return_Obj_Id
), Loc
),
5797 Relocate_Node
(Expression
(Init_Assignment
))));
5800 -- In the case of functions where the calling context can
5801 -- determine the form of allocation needed, initialization
5802 -- is done with each part of the if statement that handles
5803 -- the different forms of allocation (this is true for
5804 -- unconstrained and tagged result subtypes).
5807 and then not Is_Tagged_Type
(Underlying_Type
(Result_Subt
))
5809 Insert_After
(Ret_Obj_Decl
, Init_Assignment
);
5813 -- When the function's subtype is unconstrained, a run-time
5814 -- test is needed to determine the form of allocation to use
5815 -- for the return object. The function has an implicit formal
5816 -- parameter indicating this. If the BIP_Alloc_Form formal has
5817 -- the value one, then the caller has passed access to an
5818 -- existing object for use as the return object. If the value
5819 -- is two, then the return object must be allocated on the
5820 -- secondary stack. Otherwise, the object must be allocated in
5821 -- a storage pool (currently only supported for the global
5822 -- heap, user-defined storage pools TBD ???). We generate an
5823 -- if statement to test the implicit allocation formal and
5824 -- initialize a local access value appropriately, creating
5825 -- allocators in the secondary stack and global heap cases.
5826 -- The special formal also exists and must be tested when the
5827 -- function has a tagged result, even when the result subtype
5828 -- is constrained, because in general such functions can be
5829 -- called in dispatching contexts and must be handled similarly
5830 -- to functions with a class-wide result.
5832 if not Constr_Result
5833 or else Is_Tagged_Type
(Underlying_Type
(Result_Subt
))
5836 Build_In_Place_Formal
(Par_Func
, BIP_Alloc_Form
);
5839 Pool_Id
: constant Entity_Id
:=
5840 Make_Temporary
(Loc
, 'P');
5841 Alloc_Obj_Id
: Entity_Id
;
5842 Alloc_Obj_Decl
: Node_Id
;
5843 Alloc_If_Stmt
: Node_Id
;
5844 Heap_Allocator
: Node_Id
;
5845 Pool_Decl
: Node_Id
;
5846 Pool_Allocator
: Node_Id
;
5847 Ptr_Type_Decl
: Node_Id
;
5848 Ref_Type
: Entity_Id
;
5849 SS_Allocator
: Node_Id
;
5852 -- Reuse the itype created for the function's implicit
5853 -- access formal. This avoids the need to create a new
5854 -- access type here, plus it allows assigning the access
5855 -- formal directly without applying a conversion.
5857 -- Ref_Type := Etype (Object_Access);
5859 -- Create an access type designating the function's
5862 Ref_Type
:= Make_Temporary
(Loc
, 'A');
5865 Make_Full_Type_Declaration
(Loc
,
5866 Defining_Identifier
=> Ref_Type
,
5868 Make_Access_To_Object_Definition
(Loc
,
5869 All_Present
=> True,
5870 Subtype_Indication
=>
5871 New_Reference_To
(Return_Obj_Typ
, Loc
)));
5873 Insert_Before
(Ret_Obj_Decl
, Ptr_Type_Decl
);
5875 -- Create an access object that will be initialized to an
5876 -- access value denoting the return object, either coming
5877 -- from an implicit access value passed in by the caller
5878 -- or from the result of an allocator.
5880 Alloc_Obj_Id
:= Make_Temporary
(Loc
, 'R');
5881 Set_Etype
(Alloc_Obj_Id
, Ref_Type
);
5884 Make_Object_Declaration
(Loc
,
5885 Defining_Identifier
=> Alloc_Obj_Id
,
5886 Object_Definition
=>
5887 New_Reference_To
(Ref_Type
, Loc
));
5889 Insert_Before
(Ret_Obj_Decl
, Alloc_Obj_Decl
);
5891 -- Create allocators for both the secondary stack and
5892 -- global heap. If there's an initialization expression,
5893 -- then create these as initialized allocators.
5895 if Present
(Return_Obj_Expr
)
5896 and then not No_Initialization
(Ret_Obj_Decl
)
5898 -- Always use the type of the expression for the
5899 -- qualified expression, rather than the result type.
5900 -- In general we cannot always use the result type
5901 -- for the allocator, because the expression might be
5902 -- of a specific type, such as in the case of an
5903 -- aggregate or even a nonlimited object when the
5904 -- result type is a limited class-wide interface type.
5907 Make_Allocator
(Loc
,
5909 Make_Qualified_Expression
(Loc
,
5912 (Etype
(Return_Obj_Expr
), Loc
),
5914 New_Copy_Tree
(Return_Obj_Expr
)));
5917 -- If the function returns a class-wide type we cannot
5918 -- use the return type for the allocator. Instead we
5919 -- use the type of the expression, which must be an
5920 -- aggregate of a definite type.
5922 if Is_Class_Wide_Type
(Return_Obj_Typ
) then
5924 Make_Allocator
(Loc
,
5927 (Etype
(Return_Obj_Expr
), Loc
));
5930 Make_Allocator
(Loc
,
5932 New_Reference_To
(Return_Obj_Typ
, Loc
));
5935 -- If the object requires default initialization then
5936 -- that will happen later following the elaboration of
5937 -- the object renaming. If we don't turn it off here
5938 -- then the object will be default initialized twice.
5940 Set_No_Initialization
(Heap_Allocator
);
5943 -- The Pool_Allocator is just like the Heap_Allocator,
5944 -- except we set Storage_Pool and Procedure_To_Call so
5945 -- it will use the user-defined storage pool.
5947 Pool_Allocator
:= New_Copy_Tree
(Heap_Allocator
);
5949 -- Do not generate the renaming of the build-in-place
5950 -- pool parameter on .NET/JVM/ZFP because the parameter
5951 -- is not created in the first place.
5953 if VM_Target
= No_VM
5954 and then RTE_Available
(RE_Root_Storage_Pool_Ptr
)
5957 Make_Object_Renaming_Declaration
(Loc
,
5958 Defining_Identifier
=> Pool_Id
,
5961 (RTE
(RE_Root_Storage_Pool
), Loc
),
5963 Make_Explicit_Dereference
(Loc
,
5965 (Build_In_Place_Formal
5966 (Par_Func
, BIP_Storage_Pool
), Loc
)));
5967 Set_Storage_Pool
(Pool_Allocator
, Pool_Id
);
5968 Set_Procedure_To_Call
5969 (Pool_Allocator
, RTE
(RE_Allocate_Any
));
5971 Pool_Decl
:= Make_Null_Statement
(Loc
);
5974 -- If the No_Allocators restriction is active, then only
5975 -- an allocator for secondary stack allocation is needed.
5976 -- It's OK for such allocators to have Comes_From_Source
5977 -- set to False, because gigi knows not to flag them as
5978 -- being a violation of No_Implicit_Heap_Allocations.
5980 if Restriction_Active
(No_Allocators
) then
5981 SS_Allocator
:= Heap_Allocator
;
5982 Heap_Allocator
:= Make_Null
(Loc
);
5983 Pool_Allocator
:= Make_Null
(Loc
);
5985 -- Otherwise the heap and pool allocators may be needed,
5986 -- so we make another allocator for secondary stack
5990 SS_Allocator
:= New_Copy_Tree
(Heap_Allocator
);
5992 -- The heap and pool allocators are marked as
5993 -- Comes_From_Source since they correspond to an
5994 -- explicit user-written allocator (that is, it will
5995 -- only be executed on behalf of callers that call the
5996 -- function as initialization for such an allocator).
5997 -- Prevents errors when No_Implicit_Heap_Allocations
6000 Set_Comes_From_Source
(Heap_Allocator
, True);
6001 Set_Comes_From_Source
(Pool_Allocator
, True);
6004 -- The allocator is returned on the secondary stack. We
6005 -- don't do this on VM targets, since the SS is not used.
6007 if VM_Target
= No_VM
then
6008 Set_Storage_Pool
(SS_Allocator
, RTE
(RE_SS_Pool
));
6009 Set_Procedure_To_Call
6010 (SS_Allocator
, RTE
(RE_SS_Allocate
));
6012 -- The allocator is returned on the secondary stack,
6013 -- so indicate that the function return, as well as
6014 -- the block that encloses the allocator, must not
6015 -- release it. The flags must be set now because
6016 -- the decision to use the secondary stack is done
6017 -- very late in the course of expanding the return
6018 -- statement, past the point where these flags are
6021 Set_Sec_Stack_Needed_For_Return
(Par_Func
);
6022 Set_Sec_Stack_Needed_For_Return
6023 (Return_Statement_Entity
(N
));
6024 Set_Uses_Sec_Stack
(Par_Func
);
6025 Set_Uses_Sec_Stack
(Return_Statement_Entity
(N
));
6028 -- Create an if statement to test the BIP_Alloc_Form
6029 -- formal and initialize the access object to either the
6030 -- BIP_Object_Access formal (BIP_Alloc_Form =
6031 -- Caller_Allocation), the result of allocating the
6032 -- object in the secondary stack (BIP_Alloc_Form =
6033 -- Secondary_Stack), or else an allocator to create the
6034 -- return object in the heap or user-defined pool
6035 -- (BIP_Alloc_Form = Global_Heap or User_Storage_Pool).
6037 -- ??? An unchecked type conversion must be made in the
6038 -- case of assigning the access object formal to the
6039 -- local access object, because a normal conversion would
6040 -- be illegal in some cases (such as converting access-
6041 -- to-unconstrained to access-to-constrained), but the
6042 -- the unchecked conversion will presumably fail to work
6043 -- right in just such cases. It's not clear at all how to
6047 Make_If_Statement
(Loc
,
6051 New_Reference_To
(Obj_Alloc_Formal
, Loc
),
6053 Make_Integer_Literal
(Loc
,
6054 UI_From_Int
(BIP_Allocation_Form
'Pos
6055 (Caller_Allocation
)))),
6057 Then_Statements
=> New_List
(
6058 Make_Assignment_Statement
(Loc
,
6060 New_Reference_To
(Alloc_Obj_Id
, Loc
),
6062 Make_Unchecked_Type_Conversion
(Loc
,
6064 New_Reference_To
(Ref_Type
, Loc
),
6066 New_Reference_To
(Object_Access
, Loc
)))),
6068 Elsif_Parts
=> New_List
(
6069 Make_Elsif_Part
(Loc
,
6073 New_Reference_To
(Obj_Alloc_Formal
, Loc
),
6075 Make_Integer_Literal
(Loc
,
6076 UI_From_Int
(BIP_Allocation_Form
'Pos
6077 (Secondary_Stack
)))),
6079 Then_Statements
=> New_List
(
6080 Make_Assignment_Statement
(Loc
,
6082 New_Reference_To
(Alloc_Obj_Id
, Loc
),
6083 Expression
=> SS_Allocator
))),
6085 Make_Elsif_Part
(Loc
,
6089 New_Reference_To
(Obj_Alloc_Formal
, Loc
),
6091 Make_Integer_Literal
(Loc
,
6092 UI_From_Int
(BIP_Allocation_Form
'Pos
6095 Then_Statements
=> New_List
(
6096 Build_Heap_Allocator
6097 (Temp_Id
=> Alloc_Obj_Id
,
6098 Temp_Typ
=> Ref_Type
,
6099 Func_Id
=> Par_Func
,
6100 Ret_Typ
=> Return_Obj_Typ
,
6101 Alloc_Expr
=> Heap_Allocator
)))),
6103 Else_Statements
=> New_List
(
6105 Build_Heap_Allocator
6106 (Temp_Id
=> Alloc_Obj_Id
,
6107 Temp_Typ
=> Ref_Type
,
6108 Func_Id
=> Par_Func
,
6109 Ret_Typ
=> Return_Obj_Typ
,
6110 Alloc_Expr
=> Pool_Allocator
)));
6112 -- If a separate initialization assignment was created
6113 -- earlier, append that following the assignment of the
6114 -- implicit access formal to the access object, to ensure
6115 -- that the return object is initialized in that case. In
6116 -- this situation, the target of the assignment must be
6117 -- rewritten to denote a dereference of the access to the
6118 -- return object passed in by the caller.
6120 if Present
(Init_Assignment
) then
6121 Rewrite
(Name
(Init_Assignment
),
6122 Make_Explicit_Dereference
(Loc
,
6123 Prefix
=> New_Reference_To
(Alloc_Obj_Id
, Loc
)));
6126 (Name
(Init_Assignment
), Etype
(Return_Obj_Id
));
6129 (Then_Statements
(Alloc_If_Stmt
), Init_Assignment
);
6132 Insert_Before
(Ret_Obj_Decl
, Alloc_If_Stmt
);
6134 -- Remember the local access object for use in the
6135 -- dereference of the renaming created below.
6137 Object_Access
:= Alloc_Obj_Id
;
6141 -- Replace the return object declaration with a renaming of a
6142 -- dereference of the access value designating the return
6146 Make_Explicit_Dereference
(Loc
,
6147 Prefix
=> New_Reference_To
(Object_Access
, Loc
));
6149 Rewrite
(Ret_Obj_Decl
,
6150 Make_Object_Renaming_Declaration
(Loc
,
6151 Defining_Identifier
=> Return_Obj_Id
,
6152 Access_Definition
=> Empty
,
6154 New_Occurrence_Of
(Return_Obj_Typ
, Loc
),
6155 Name
=> Obj_Acc_Deref
));
6157 Set_Renamed_Object
(Return_Obj_Id
, Obj_Acc_Deref
);
6161 -- Case where we do not build a block
6164 -- We're about to drop Return_Object_Declarations on the floor, so
6165 -- we need to insert it, in case it got expanded into useful code.
6166 -- Remove side effects from expression, which may be duplicated in
6167 -- subsequent checks (see Expand_Simple_Function_Return).
6169 Insert_List_Before
(N
, Return_Object_Declarations
(N
));
6170 Remove_Side_Effects
(Exp
);
6172 -- Build simple_return_statement that returns the expression directly
6174 Return_Stmt
:= Make_Simple_Return_Statement
(Loc
, Expression
=> Exp
);
6175 Result
:= Return_Stmt
;
6178 -- Set the flag to prevent infinite recursion
6180 Set_Comes_From_Extended_Return_Statement
(Return_Stmt
);
6182 Rewrite
(N
, Result
);
6184 end Expand_N_Extended_Return_Statement
;
6186 ----------------------------
6187 -- Expand_N_Function_Call --
6188 ----------------------------
6190 procedure Expand_N_Function_Call
(N
: Node_Id
) is
6194 -- If the return value of a foreign compiled function is VAX Float, then
6195 -- expand the return (adjusts the location of the return value on
6196 -- Alpha/VMS, no-op everywhere else).
6197 -- Comes_From_Source intercepts recursive expansion.
6199 if Nkind
(N
) = N_Function_Call
6200 and then Vax_Float
(Etype
(N
))
6201 and then Present
(Name
(N
))
6202 and then Present
(Entity
(Name
(N
)))
6203 and then Has_Foreign_Convention
(Entity
(Name
(N
)))
6204 and then Comes_From_Source
(Parent
(N
))
6206 Expand_Vax_Foreign_Return
(N
);
6208 end Expand_N_Function_Call
;
6210 ---------------------------------------
6211 -- Expand_N_Procedure_Call_Statement --
6212 ---------------------------------------
6214 procedure Expand_N_Procedure_Call_Statement
(N
: Node_Id
) is
6217 end Expand_N_Procedure_Call_Statement
;
6219 --------------------------------------
6220 -- Expand_N_Simple_Return_Statement --
6221 --------------------------------------
6223 procedure Expand_N_Simple_Return_Statement
(N
: Node_Id
) is
6225 -- Defend against previous errors (i.e. the return statement calls a
6226 -- function that is not available in configurable runtime).
6228 if Present
(Expression
(N
))
6229 and then Nkind
(Expression
(N
)) = N_Empty
6231 Check_Error_Detected
;
6235 -- Distinguish the function and non-function cases:
6237 case Ekind
(Return_Applies_To
(Return_Statement_Entity
(N
))) is
6240 E_Generic_Function
=>
6241 Expand_Simple_Function_Return
(N
);
6244 E_Generic_Procedure |
6247 E_Return_Statement
=>
6248 Expand_Non_Function_Return
(N
);
6251 raise Program_Error
;
6255 when RE_Not_Available
=>
6257 end Expand_N_Simple_Return_Statement
;
6259 ------------------------------
6260 -- Expand_N_Subprogram_Body --
6261 ------------------------------
6263 -- Add poll call if ATC polling is enabled, unless the body will be inlined
6266 -- Add dummy push/pop label nodes at start and end to clear any local
6267 -- exception indications if local-exception-to-goto optimization is active.
6269 -- Add return statement if last statement in body is not a return statement
6270 -- (this makes things easier on Gigi which does not want to have to handle
6271 -- a missing return).
6273 -- Add call to Activate_Tasks if body is a task activator
6275 -- Deal with possible detection of infinite recursion
6277 -- Eliminate body completely if convention stubbed
6279 -- Encode entity names within body, since we will not need to reference
6280 -- these entities any longer in the front end.
6282 -- Initialize scalar out parameters if Initialize/Normalize_Scalars
6284 -- Reset Pure indication if any parameter has root type System.Address
6285 -- or has any parameters of limited types, where limited means that the
6286 -- run-time view is limited (i.e. the full type is limited).
6290 procedure Expand_N_Subprogram_Body
(N
: Node_Id
) is
6291 Loc
: constant Source_Ptr
:= Sloc
(N
);
6292 H
: constant Node_Id
:= Handled_Statement_Sequence
(N
);
6293 Body_Id
: Entity_Id
;
6296 Spec_Id
: Entity_Id
;
6298 procedure Add_Return
(S
: List_Id
);
6299 -- Append a return statement to the statement sequence S if the last
6300 -- statement is not already a return or a goto statement. Note that
6301 -- the latter test is not critical, it does not matter if we add a few
6302 -- extra returns, since they get eliminated anyway later on.
6308 procedure Add_Return
(S
: List_Id
) is
6313 -- Get last statement, ignoring any Pop_xxx_Label nodes, which are
6314 -- not relevant in this context since they are not executable.
6316 Last_Stm
:= Last
(S
);
6317 while Nkind
(Last_Stm
) in N_Pop_xxx_Label
loop
6321 -- Now insert return unless last statement is a transfer
6323 if not Is_Transfer
(Last_Stm
) then
6325 -- The source location for the return is the end label of the
6326 -- procedure if present. Otherwise use the sloc of the last
6327 -- statement in the list. If the list comes from a generated
6328 -- exception handler and we are not debugging generated code,
6329 -- all the statements within the handler are made invisible
6332 if Nkind
(Parent
(S
)) = N_Exception_Handler
6333 and then not Comes_From_Source
(Parent
(S
))
6335 Loc
:= Sloc
(Last_Stm
);
6336 elsif Present
(End_Label
(H
)) then
6337 Loc
:= Sloc
(End_Label
(H
));
6339 Loc
:= Sloc
(Last_Stm
);
6343 Rtn
: constant Node_Id
:= Make_Simple_Return_Statement
(Loc
);
6346 -- Append return statement, and set analyzed manually. We can't
6347 -- call Analyze on this return since the scope is wrong.
6349 -- Note: it almost works to push the scope and then do the
6350 -- Analyze call, but something goes wrong in some weird cases
6351 -- and it is not worth worrying about ???
6356 -- Call _Postconditions procedure if appropriate. We need to
6357 -- do this explicitly because we did not analyze the generated
6358 -- return statement above, so the call did not get inserted.
6360 if Ekind
(Spec_Id
) = E_Procedure
6361 and then Has_Postconditions
(Spec_Id
)
6363 pragma Assert
(Present
(Postcondition_Proc
(Spec_Id
)));
6365 Make_Procedure_Call_Statement
(Loc
,
6367 New_Reference_To
(Postcondition_Proc
(Spec_Id
), Loc
)));
6373 -- Start of processing for Expand_N_Subprogram_Body
6376 -- Set L to either the list of declarations if present, or to the list
6377 -- of statements if no declarations are present. This is used to insert
6378 -- new stuff at the start.
6380 if Is_Non_Empty_List
(Declarations
(N
)) then
6381 L
:= Declarations
(N
);
6383 L
:= Statements
(H
);
6386 -- If local-exception-to-goto optimization active, insert dummy push
6387 -- statements at start, and dummy pop statements at end, but inhibit
6388 -- this if we have No_Exception_Handlers, since they are useless and
6389 -- intefere with analysis, e.g. by codepeer.
6391 if (Debug_Flag_Dot_G
6392 or else Restriction_Active
(No_Exception_Propagation
))
6393 and then not Restriction_Active
(No_Exception_Handlers
)
6394 and then not CodePeer_Mode
6395 and then Is_Non_Empty_List
(L
)
6398 FS
: constant Node_Id
:= First
(L
);
6399 FL
: constant Source_Ptr
:= Sloc
(FS
);
6404 -- LS points to either last statement, if statements are present
6405 -- or to the last declaration if there are no statements present.
6406 -- It is the node after which the pop's are generated.
6408 if Is_Non_Empty_List
(Statements
(H
)) then
6409 LS
:= Last
(Statements
(H
));
6416 Insert_List_Before_And_Analyze
(FS
, New_List
(
6417 Make_Push_Constraint_Error_Label
(FL
),
6418 Make_Push_Program_Error_Label
(FL
),
6419 Make_Push_Storage_Error_Label
(FL
)));
6421 Insert_List_After_And_Analyze
(LS
, New_List
(
6422 Make_Pop_Constraint_Error_Label
(LL
),
6423 Make_Pop_Program_Error_Label
(LL
),
6424 Make_Pop_Storage_Error_Label
(LL
)));
6428 -- Find entity for subprogram
6430 Body_Id
:= Defining_Entity
(N
);
6432 if Present
(Corresponding_Spec
(N
)) then
6433 Spec_Id
:= Corresponding_Spec
(N
);
6438 -- Need poll on entry to subprogram if polling enabled. We only do this
6439 -- for non-empty subprograms, since it does not seem necessary to poll
6440 -- for a dummy null subprogram.
6442 if Is_Non_Empty_List
(L
) then
6444 -- Do not add a polling call if the subprogram is to be inlined by
6445 -- the back-end, to avoid repeated calls with multiple inlinings.
6447 if Is_Inlined
(Spec_Id
)
6448 and then Front_End_Inlining
6449 and then Optimization_Level
> 1
6453 Generate_Poll_Call
(First
(L
));
6457 -- If this is a Pure function which has any parameters whose root type
6458 -- is System.Address, reset the Pure indication, since it will likely
6459 -- cause incorrect code to be generated as the parameter is probably
6460 -- a pointer, and the fact that the same pointer is passed does not mean
6461 -- that the same value is being referenced.
6463 -- Note that if the programmer gave an explicit Pure_Function pragma,
6464 -- then we believe the programmer, and leave the subprogram Pure.
6466 -- This code should probably be at the freeze point, so that it happens
6467 -- even on a -gnatc (or more importantly -gnatt) compile, so that the
6468 -- semantic tree has Is_Pure set properly ???
6470 if Is_Pure
(Spec_Id
)
6471 and then Is_Subprogram
(Spec_Id
)
6472 and then not Has_Pragma_Pure_Function
(Spec_Id
)
6478 F
:= First_Formal
(Spec_Id
);
6479 while Present
(F
) loop
6480 if Is_Descendent_Of_Address
(Etype
(F
))
6482 -- Note that this test is being made in the body of the
6483 -- subprogram, not the spec, so we are testing the full
6484 -- type for being limited here, as required.
6486 or else Is_Limited_Type
(Etype
(F
))
6488 Set_Is_Pure
(Spec_Id
, False);
6490 if Spec_Id
/= Body_Id
then
6491 Set_Is_Pure
(Body_Id
, False);
6502 -- Initialize any scalar OUT args if Initialize/Normalize_Scalars
6504 if Init_Or_Norm_Scalars
and then Is_Subprogram
(Spec_Id
) then
6509 -- Loop through formals
6511 F
:= First_Formal
(Spec_Id
);
6512 while Present
(F
) loop
6513 if Is_Scalar_Type
(Etype
(F
))
6514 and then Ekind
(F
) = E_Out_Parameter
6516 Check_Restriction
(No_Default_Initialization
, F
);
6518 -- Insert the initialization. We turn off validity checks
6519 -- for this assignment, since we do not want any check on
6520 -- the initial value itself (which may well be invalid).
6522 Insert_Before_And_Analyze
(First
(L
),
6523 Make_Assignment_Statement
(Loc
,
6524 Name
=> New_Occurrence_Of
(F
, Loc
),
6525 Expression
=> Get_Simple_Init_Val
(Etype
(F
), N
)),
6526 Suppress
=> Validity_Check
);
6534 -- Clear out statement list for stubbed procedure
6536 if Present
(Corresponding_Spec
(N
)) then
6537 Set_Elaboration_Flag
(N
, Spec_Id
);
6539 if Convention
(Spec_Id
) = Convention_Stubbed
6540 or else Is_Eliminated
(Spec_Id
)
6542 Set_Declarations
(N
, Empty_List
);
6543 Set_Handled_Statement_Sequence
(N
,
6544 Make_Handled_Sequence_Of_Statements
(Loc
,
6545 Statements
=> New_List
(Make_Null_Statement
(Loc
))));
6550 -- Create a set of discriminals for the next protected subprogram body
6552 if Is_List_Member
(N
)
6553 and then Present
(Parent
(List_Containing
(N
)))
6554 and then Nkind
(Parent
(List_Containing
(N
))) = N_Protected_Body
6555 and then Present
(Next_Protected_Operation
(N
))
6557 Set_Discriminals
(Parent
(Base_Type
(Scope
(Spec_Id
))));
6560 -- Returns_By_Ref flag is normally set when the subprogram is frozen but
6561 -- subprograms with no specs are not frozen.
6564 Typ
: constant Entity_Id
:= Etype
(Spec_Id
);
6565 Utyp
: constant Entity_Id
:= Underlying_Type
(Typ
);
6568 if not Acts_As_Spec
(N
)
6569 and then Nkind
(Parent
(Parent
(Spec_Id
))) /=
6570 N_Subprogram_Body_Stub
6574 elsif Is_Immutably_Limited_Type
(Typ
) then
6575 Set_Returns_By_Ref
(Spec_Id
);
6577 elsif Present
(Utyp
) and then CW_Or_Has_Controlled_Part
(Utyp
) then
6578 Set_Returns_By_Ref
(Spec_Id
);
6582 -- For a procedure, we add a return for all possible syntactic ends of
6585 if Ekind_In
(Spec_Id
, E_Procedure
, E_Generic_Procedure
) then
6586 Add_Return
(Statements
(H
));
6588 if Present
(Exception_Handlers
(H
)) then
6589 Except_H
:= First_Non_Pragma
(Exception_Handlers
(H
));
6590 while Present
(Except_H
) loop
6591 Add_Return
(Statements
(Except_H
));
6592 Next_Non_Pragma
(Except_H
);
6596 -- For a function, we must deal with the case where there is at least
6597 -- one missing return. What we do is to wrap the entire body of the
6598 -- function in a block:
6611 -- raise Program_Error;
6614 -- This approach is necessary because the raise must be signalled to the
6615 -- caller, not handled by any local handler (RM 6.4(11)).
6617 -- Note: we do not need to analyze the constructed sequence here, since
6618 -- it has no handler, and an attempt to analyze the handled statement
6619 -- sequence twice is risky in various ways (e.g. the issue of expanding
6620 -- cleanup actions twice).
6622 elsif Has_Missing_Return
(Spec_Id
) then
6624 Hloc
: constant Source_Ptr
:= Sloc
(H
);
6625 Blok
: constant Node_Id
:=
6626 Make_Block_Statement
(Hloc
,
6627 Handled_Statement_Sequence
=> H
);
6628 Rais
: constant Node_Id
:=
6629 Make_Raise_Program_Error
(Hloc
,
6630 Reason
=> PE_Missing_Return
);
6633 Set_Handled_Statement_Sequence
(N
,
6634 Make_Handled_Sequence_Of_Statements
(Hloc
,
6635 Statements
=> New_List
(Blok
, Rais
)));
6637 Push_Scope
(Spec_Id
);
6644 -- If subprogram contains a parameterless recursive call, then we may
6645 -- have an infinite recursion, so see if we can generate code to check
6646 -- for this possibility if storage checks are not suppressed.
6648 if Ekind
(Spec_Id
) = E_Procedure
6649 and then Has_Recursive_Call
(Spec_Id
)
6650 and then not Storage_Checks_Suppressed
(Spec_Id
)
6652 Detect_Infinite_Recursion
(N
, Spec_Id
);
6655 -- Set to encode entity names in package body before gigi is called
6657 Qualify_Entity_Names
(N
);
6658 end Expand_N_Subprogram_Body
;
6660 -----------------------------------
6661 -- Expand_N_Subprogram_Body_Stub --
6662 -----------------------------------
6664 procedure Expand_N_Subprogram_Body_Stub
(N
: Node_Id
) is
6666 if Present
(Corresponding_Body
(N
)) then
6667 Expand_N_Subprogram_Body
(
6668 Unit_Declaration_Node
(Corresponding_Body
(N
)));
6670 end Expand_N_Subprogram_Body_Stub
;
6672 -------------------------------------
6673 -- Expand_N_Subprogram_Declaration --
6674 -------------------------------------
6676 -- If the declaration appears within a protected body, it is a private
6677 -- operation of the protected type. We must create the corresponding
6678 -- protected subprogram an associated formals. For a normal protected
6679 -- operation, this is done when expanding the protected type declaration.
6681 -- If the declaration is for a null procedure, emit null body
6683 procedure Expand_N_Subprogram_Declaration
(N
: Node_Id
) is
6684 Loc
: constant Source_Ptr
:= Sloc
(N
);
6685 Subp
: constant Entity_Id
:= Defining_Entity
(N
);
6686 Scop
: constant Entity_Id
:= Scope
(Subp
);
6687 Prot_Decl
: Node_Id
;
6689 Prot_Id
: Entity_Id
;
6692 -- In SPARK, subprogram declarations are only allowed in package
6695 if Nkind
(Parent
(N
)) /= N_Package_Specification
then
6696 if Nkind
(Parent
(N
)) = N_Compilation_Unit
then
6697 Check_SPARK_Restriction
6698 ("subprogram declaration is not a library item", N
);
6700 elsif Present
(Next
(N
))
6701 and then Nkind
(Next
(N
)) = N_Pragma
6702 and then Get_Pragma_Id
(Pragma_Name
(Next
(N
))) = Pragma_Import
6704 -- In SPARK, subprogram declarations are also permitted in
6705 -- declarative parts when immediately followed by a corresponding
6706 -- pragma Import. We only check here that there is some pragma
6711 Check_SPARK_Restriction
6712 ("subprogram declaration is not allowed here", N
);
6716 -- Deal with case of protected subprogram. Do not generate protected
6717 -- operation if operation is flagged as eliminated.
6719 if Is_List_Member
(N
)
6720 and then Present
(Parent
(List_Containing
(N
)))
6721 and then Nkind
(Parent
(List_Containing
(N
))) = N_Protected_Body
6722 and then Is_Protected_Type
(Scop
)
6724 if No
(Protected_Body_Subprogram
(Subp
))
6725 and then not Is_Eliminated
(Subp
)
6728 Make_Subprogram_Declaration
(Loc
,
6730 Build_Protected_Sub_Specification
6731 (N
, Scop
, Unprotected_Mode
));
6733 -- The protected subprogram is declared outside of the protected
6734 -- body. Given that the body has frozen all entities so far, we
6735 -- analyze the subprogram and perform freezing actions explicitly.
6736 -- including the generation of an explicit freeze node, to ensure
6737 -- that gigi has the proper order of elaboration.
6738 -- If the body is a subunit, the insertion point is before the
6739 -- stub in the parent.
6741 Prot_Bod
:= Parent
(List_Containing
(N
));
6743 if Nkind
(Parent
(Prot_Bod
)) = N_Subunit
then
6744 Prot_Bod
:= Corresponding_Stub
(Parent
(Prot_Bod
));
6747 Insert_Before
(Prot_Bod
, Prot_Decl
);
6748 Prot_Id
:= Defining_Unit_Name
(Specification
(Prot_Decl
));
6749 Set_Has_Delayed_Freeze
(Prot_Id
);
6751 Push_Scope
(Scope
(Scop
));
6752 Analyze
(Prot_Decl
);
6753 Freeze_Before
(N
, Prot_Id
);
6754 Set_Protected_Body_Subprogram
(Subp
, Prot_Id
);
6756 -- Create protected operation as well. Even though the operation
6757 -- is only accessible within the body, it is possible to make it
6758 -- available outside of the protected object by using 'Access to
6759 -- provide a callback, so build protected version in all cases.
6762 Make_Subprogram_Declaration
(Loc
,
6764 Build_Protected_Sub_Specification
(N
, Scop
, Protected_Mode
));
6765 Insert_Before
(Prot_Bod
, Prot_Decl
);
6766 Analyze
(Prot_Decl
);
6771 -- Ada 2005 (AI-348): Generate body for a null procedure. In most
6772 -- cases this is superfluous because calls to it will be automatically
6773 -- inlined, but we definitely need the body if preconditions for the
6774 -- procedure are present.
6776 elsif Nkind
(Specification
(N
)) = N_Procedure_Specification
6777 and then Null_Present
(Specification
(N
))
6780 Bod
: constant Node_Id
:= Body_To_Inline
(N
);
6783 Set_Has_Completion
(Subp
, False);
6784 Append_Freeze_Action
(Subp
, Bod
);
6786 -- The body now contains raise statements, so calls to it will
6789 Set_Is_Inlined
(Subp
, False);
6792 end Expand_N_Subprogram_Declaration
;
6794 --------------------------------
6795 -- Expand_Non_Function_Return --
6796 --------------------------------
6798 procedure Expand_Non_Function_Return
(N
: Node_Id
) is
6799 pragma Assert
(No
(Expression
(N
)));
6801 Loc
: constant Source_Ptr
:= Sloc
(N
);
6802 Scope_Id
: Entity_Id
:=
6803 Return_Applies_To
(Return_Statement_Entity
(N
));
6804 Kind
: constant Entity_Kind
:= Ekind
(Scope_Id
);
6807 Goto_Stat
: Node_Id
;
6811 -- Call _Postconditions procedure if procedure with active
6812 -- postconditions. Here, we use the Postcondition_Proc attribute,
6813 -- which is needed for implicitly-generated returns. Functions
6814 -- never have implicitly-generated returns, and there's no
6815 -- room for Postcondition_Proc in E_Function, so we look up the
6816 -- identifier Name_uPostconditions for function returns (see
6817 -- Expand_Simple_Function_Return).
6819 if Ekind
(Scope_Id
) = E_Procedure
6820 and then Has_Postconditions
(Scope_Id
)
6822 pragma Assert
(Present
(Postcondition_Proc
(Scope_Id
)));
6824 Make_Procedure_Call_Statement
(Loc
,
6825 Name
=> New_Reference_To
(Postcondition_Proc
(Scope_Id
), Loc
)));
6828 -- If it is a return from a procedure do no extra steps
6830 if Kind
= E_Procedure
or else Kind
= E_Generic_Procedure
then
6833 -- If it is a nested return within an extended one, replace it with a
6834 -- return of the previously declared return object.
6836 elsif Kind
= E_Return_Statement
then
6838 Make_Simple_Return_Statement
(Loc
,
6840 New_Occurrence_Of
(First_Entity
(Scope_Id
), Loc
)));
6841 Set_Comes_From_Extended_Return_Statement
(N
);
6842 Set_Return_Statement_Entity
(N
, Scope_Id
);
6843 Expand_Simple_Function_Return
(N
);
6847 pragma Assert
(Is_Entry
(Scope_Id
));
6849 -- Look at the enclosing block to see whether the return is from an
6850 -- accept statement or an entry body.
6852 for J
in reverse 0 .. Scope_Stack
.Last
loop
6853 Scope_Id
:= Scope_Stack
.Table
(J
).Entity
;
6854 exit when Is_Concurrent_Type
(Scope_Id
);
6857 -- If it is a return from accept statement it is expanded as call to
6858 -- RTS Complete_Rendezvous and a goto to the end of the accept body.
6860 -- (cf : Expand_N_Accept_Statement, Expand_N_Selective_Accept,
6861 -- Expand_N_Accept_Alternative in exp_ch9.adb)
6863 if Is_Task_Type
(Scope_Id
) then
6866 Make_Procedure_Call_Statement
(Loc
,
6867 Name
=> New_Reference_To
(RTE
(RE_Complete_Rendezvous
), Loc
));
6868 Insert_Before
(N
, Call
);
6869 -- why not insert actions here???
6872 Acc_Stat
:= Parent
(N
);
6873 while Nkind
(Acc_Stat
) /= N_Accept_Statement
loop
6874 Acc_Stat
:= Parent
(Acc_Stat
);
6877 Lab_Node
:= Last
(Statements
6878 (Handled_Statement_Sequence
(Acc_Stat
)));
6880 Goto_Stat
:= Make_Goto_Statement
(Loc
,
6881 Name
=> New_Occurrence_Of
6882 (Entity
(Identifier
(Lab_Node
)), Loc
));
6884 Set_Analyzed
(Goto_Stat
);
6886 Rewrite
(N
, Goto_Stat
);
6889 -- If it is a return from an entry body, put a Complete_Entry_Body call
6890 -- in front of the return.
6892 elsif Is_Protected_Type
(Scope_Id
) then
6894 Make_Procedure_Call_Statement
(Loc
,
6896 New_Reference_To
(RTE
(RE_Complete_Entry_Body
), Loc
),
6897 Parameter_Associations
=> New_List
(
6898 Make_Attribute_Reference
(Loc
,
6901 (Find_Protection_Object
(Current_Scope
), Loc
),
6902 Attribute_Name
=> Name_Unchecked_Access
)));
6904 Insert_Before
(N
, Call
);
6907 end Expand_Non_Function_Return
;
6909 ---------------------------------------
6910 -- Expand_Protected_Object_Reference --
6911 ---------------------------------------
6913 function Expand_Protected_Object_Reference
6915 Scop
: Entity_Id
) return Node_Id
6917 Loc
: constant Source_Ptr
:= Sloc
(N
);
6924 Rec
:= Make_Identifier
(Loc
, Name_uObject
);
6925 Set_Etype
(Rec
, Corresponding_Record_Type
(Scop
));
6927 -- Find enclosing protected operation, and retrieve its first parameter,
6928 -- which denotes the enclosing protected object. If the enclosing
6929 -- operation is an entry, we are immediately within the protected body,
6930 -- and we can retrieve the object from the service entries procedure. A
6931 -- barrier function has the same signature as an entry. A barrier
6932 -- function is compiled within the protected object, but unlike
6933 -- protected operations its never needs locks, so that its protected
6934 -- body subprogram points to itself.
6936 Proc
:= Current_Scope
;
6937 while Present
(Proc
)
6938 and then Scope
(Proc
) /= Scop
6940 Proc
:= Scope
(Proc
);
6943 Corr
:= Protected_Body_Subprogram
(Proc
);
6947 -- Previous error left expansion incomplete.
6948 -- Nothing to do on this call.
6955 (First
(Parameter_Specifications
(Parent
(Corr
))));
6957 if Is_Subprogram
(Proc
)
6958 and then Proc
/= Corr
6960 -- Protected function or procedure
6962 Set_Entity
(Rec
, Param
);
6964 -- Rec is a reference to an entity which will not be in scope when
6965 -- the call is reanalyzed, and needs no further analysis.
6970 -- Entry or barrier function for entry body. The first parameter of
6971 -- the entry body procedure is pointer to the object. We create a
6972 -- local variable of the proper type, duplicating what is done to
6973 -- define _object later on.
6977 Obj_Ptr
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T');
6981 Make_Full_Type_Declaration
(Loc
,
6982 Defining_Identifier
=> Obj_Ptr
,
6984 Make_Access_To_Object_Definition
(Loc
,
6985 Subtype_Indication
=>
6987 (Corresponding_Record_Type
(Scop
), Loc
))));
6989 Insert_Actions
(N
, Decls
);
6990 Freeze_Before
(N
, Obj_Ptr
);
6993 Make_Explicit_Dereference
(Loc
,
6995 Unchecked_Convert_To
(Obj_Ptr
,
6996 New_Occurrence_Of
(Param
, Loc
)));
6998 -- Analyze new actual. Other actuals in calls are already analyzed
6999 -- and the list of actuals is not reanalyzed after rewriting.
7001 Set_Parent
(Rec
, N
);
7007 end Expand_Protected_Object_Reference
;
7009 --------------------------------------
7010 -- Expand_Protected_Subprogram_Call --
7011 --------------------------------------
7013 procedure Expand_Protected_Subprogram_Call
7021 -- If the protected object is not an enclosing scope, this is an inter-
7022 -- object function call. Inter-object procedure calls are expanded by
7023 -- Exp_Ch9.Build_Simple_Entry_Call. The call is intra-object only if the
7024 -- subprogram being called is in the protected body being compiled, and
7025 -- if the protected object in the call is statically the enclosing type.
7026 -- The object may be an component of some other data structure, in which
7027 -- case this must be handled as an inter-object call.
7029 if not In_Open_Scopes
(Scop
)
7030 or else not Is_Entity_Name
(Name
(N
))
7032 if Nkind
(Name
(N
)) = N_Selected_Component
then
7033 Rec
:= Prefix
(Name
(N
));
7036 pragma Assert
(Nkind
(Name
(N
)) = N_Indexed_Component
);
7037 Rec
:= Prefix
(Prefix
(Name
(N
)));
7040 Build_Protected_Subprogram_Call
(N
,
7041 Name
=> New_Occurrence_Of
(Subp
, Sloc
(N
)),
7042 Rec
=> Convert_Concurrent
(Rec
, Etype
(Rec
)),
7046 Rec
:= Expand_Protected_Object_Reference
(N
, Scop
);
7052 Build_Protected_Subprogram_Call
(N
,
7059 -- If it is a function call it can appear in elaboration code and
7060 -- the called entity must be frozen here.
7062 if Ekind
(Subp
) = E_Function
then
7063 Freeze_Expression
(Name
(N
));
7066 -- Analyze and resolve the new call. The actuals have already been
7067 -- resolved, but expansion of a function call will add extra actuals
7068 -- if needed. Analysis of a procedure call already includes resolution.
7072 if Ekind
(Subp
) = E_Function
then
7073 Resolve
(N
, Etype
(Subp
));
7075 end Expand_Protected_Subprogram_Call
;
7077 --------------------------------------------
7078 -- Has_Unconstrained_Access_Discriminants --
7079 --------------------------------------------
7081 function Has_Unconstrained_Access_Discriminants
7082 (Subtyp
: Entity_Id
) return Boolean
7087 if Has_Discriminants
(Subtyp
)
7088 and then not Is_Constrained
(Subtyp
)
7090 Discr
:= First_Discriminant
(Subtyp
);
7091 while Present
(Discr
) loop
7092 if Ekind
(Etype
(Discr
)) = E_Anonymous_Access_Type
then
7096 Next_Discriminant
(Discr
);
7101 end Has_Unconstrained_Access_Discriminants
;
7103 -----------------------------------
7104 -- Expand_Simple_Function_Return --
7105 -----------------------------------
7107 -- The "simple" comes from the syntax rule simple_return_statement. The
7108 -- semantics are not at all simple!
7110 procedure Expand_Simple_Function_Return
(N
: Node_Id
) is
7111 Loc
: constant Source_Ptr
:= Sloc
(N
);
7113 Scope_Id
: constant Entity_Id
:=
7114 Return_Applies_To
(Return_Statement_Entity
(N
));
7115 -- The function we are returning from
7117 R_Type
: constant Entity_Id
:= Etype
(Scope_Id
);
7118 -- The result type of the function
7120 Utyp
: constant Entity_Id
:= Underlying_Type
(R_Type
);
7122 Exp
: constant Node_Id
:= Expression
(N
);
7123 pragma Assert
(Present
(Exp
));
7125 Exptyp
: constant Entity_Id
:= Etype
(Exp
);
7126 -- The type of the expression (not necessarily the same as R_Type)
7128 Subtype_Ind
: Node_Id
;
7129 -- If the result type of the function is class-wide and the expression
7130 -- has a specific type, then we use the expression's type as the type of
7131 -- the return object. In cases where the expression is an aggregate that
7132 -- is built in place, this avoids the need for an expensive conversion
7133 -- of the return object to the specific type on assignments to the
7134 -- individual components.
7137 if Is_Class_Wide_Type
(R_Type
)
7138 and then not Is_Class_Wide_Type
(Etype
(Exp
))
7140 Subtype_Ind
:= New_Occurrence_Of
(Etype
(Exp
), Loc
);
7142 Subtype_Ind
:= New_Occurrence_Of
(R_Type
, Loc
);
7145 -- For the case of a simple return that does not come from an extended
7146 -- return, in the case of Ada 2005 where we are returning a limited
7147 -- type, we rewrite "return <expression>;" to be:
7149 -- return _anon_ : <return_subtype> := <expression>
7151 -- The expansion produced by Expand_N_Extended_Return_Statement will
7152 -- contain simple return statements (for example, a block containing
7153 -- simple return of the return object), which brings us back here with
7154 -- Comes_From_Extended_Return_Statement set. The reason for the barrier
7155 -- checking for a simple return that does not come from an extended
7156 -- return is to avoid this infinite recursion.
7158 -- The reason for this design is that for Ada 2005 limited returns, we
7159 -- need to reify the return object, so we can build it "in place", and
7160 -- we need a block statement to hang finalization and tasking stuff.
7162 -- ??? In order to avoid disruption, we avoid translating to extended
7163 -- return except in the cases where we really need to (Ada 2005 for
7164 -- inherently limited). We might prefer to do this translation in all
7165 -- cases (except perhaps for the case of Ada 95 inherently limited),
7166 -- in order to fully exercise the Expand_N_Extended_Return_Statement
7167 -- code. This would also allow us to do the build-in-place optimization
7168 -- for efficiency even in cases where it is semantically not required.
7170 -- As before, we check the type of the return expression rather than the
7171 -- return type of the function, because the latter may be a limited
7172 -- class-wide interface type, which is not a limited type, even though
7173 -- the type of the expression may be.
7175 if not Comes_From_Extended_Return_Statement
(N
)
7176 and then Is_Immutably_Limited_Type
(Etype
(Expression
(N
)))
7177 and then Ada_Version
>= Ada_2005
7178 and then not Debug_Flag_Dot_L
7181 Return_Object_Entity
: constant Entity_Id
:=
7182 Make_Temporary
(Loc
, 'R', Exp
);
7183 Obj_Decl
: constant Node_Id
:=
7184 Make_Object_Declaration
(Loc
,
7185 Defining_Identifier
=> Return_Object_Entity
,
7186 Object_Definition
=> Subtype_Ind
,
7189 Ext
: constant Node_Id
:= Make_Extended_Return_Statement
(Loc
,
7190 Return_Object_Declarations
=> New_List
(Obj_Decl
));
7191 -- Do not perform this high-level optimization if the result type
7192 -- is an interface because the "this" pointer must be displaced.
7201 -- Here we have a simple return statement that is part of the expansion
7202 -- of an extended return statement (either written by the user, or
7203 -- generated by the above code).
7205 -- Always normalize C/Fortran boolean result. This is not always needed,
7206 -- but it seems a good idea to minimize the passing around of non-
7207 -- normalized values, and in any case this handles the processing of
7208 -- barrier functions for protected types, which turn the condition into
7209 -- a return statement.
7211 if Is_Boolean_Type
(Exptyp
)
7212 and then Nonzero_Is_True
(Exptyp
)
7214 Adjust_Condition
(Exp
);
7215 Adjust_Result_Type
(Exp
, Exptyp
);
7218 -- Do validity check if enabled for returns
7220 if Validity_Checks_On
7221 and then Validity_Check_Returns
7226 -- Check the result expression of a scalar function against the subtype
7227 -- of the function by inserting a conversion. This conversion must
7228 -- eventually be performed for other classes of types, but for now it's
7229 -- only done for scalars.
7232 if Is_Scalar_Type
(Exptyp
) then
7233 Rewrite
(Exp
, Convert_To
(R_Type
, Exp
));
7235 -- The expression is resolved to ensure that the conversion gets
7236 -- expanded to generate a possible constraint check.
7238 Analyze_And_Resolve
(Exp
, R_Type
);
7241 -- Deal with returning variable length objects and controlled types
7243 -- Nothing to do if we are returning by reference, or this is not a
7244 -- type that requires special processing (indicated by the fact that
7245 -- it requires a cleanup scope for the secondary stack case).
7247 if Is_Immutably_Limited_Type
(Exptyp
)
7248 or else Is_Limited_Interface
(Exptyp
)
7252 elsif not Requires_Transient_Scope
(R_Type
) then
7254 -- Mutable records with no variable length components are not
7255 -- returned on the sec-stack, so we need to make sure that the
7256 -- backend will only copy back the size of the actual value, and not
7257 -- the maximum size. We create an actual subtype for this purpose.
7260 Ubt
: constant Entity_Id
:= Underlying_Type
(Base_Type
(Exptyp
));
7264 if Has_Discriminants
(Ubt
)
7265 and then not Is_Constrained
(Ubt
)
7266 and then not Has_Unchecked_Union
(Ubt
)
7268 Decl
:= Build_Actual_Subtype
(Ubt
, Exp
);
7269 Ent
:= Defining_Identifier
(Decl
);
7270 Insert_Action
(Exp
, Decl
);
7271 Rewrite
(Exp
, Unchecked_Convert_To
(Ent
, Exp
));
7272 Analyze_And_Resolve
(Exp
);
7276 -- Here if secondary stack is used
7279 -- Make sure that no surrounding block will reclaim the secondary
7280 -- stack on which we are going to put the result. Not only may this
7281 -- introduce secondary stack leaks but worse, if the reclamation is
7282 -- done too early, then the result we are returning may get
7289 while Ekind
(S
) = E_Block
or else Ekind
(S
) = E_Loop
loop
7290 Set_Sec_Stack_Needed_For_Return
(S
, True);
7291 S
:= Enclosing_Dynamic_Scope
(S
);
7295 -- Optimize the case where the result is a function call. In this
7296 -- case either the result is already on the secondary stack, or is
7297 -- already being returned with the stack pointer depressed and no
7298 -- further processing is required except to set the By_Ref flag
7299 -- to ensure that gigi does not attempt an extra unnecessary copy.
7300 -- (actually not just unnecessary but harmfully wrong in the case
7301 -- of a controlled type, where gigi does not know how to do a copy).
7302 -- To make up for a gcc 2.8.1 deficiency (???), we perform the copy
7303 -- for array types if the constrained status of the target type is
7304 -- different from that of the expression.
7306 if Requires_Transient_Scope
(Exptyp
)
7308 (not Is_Array_Type
(Exptyp
)
7309 or else Is_Constrained
(Exptyp
) = Is_Constrained
(R_Type
)
7310 or else CW_Or_Has_Controlled_Part
(Utyp
))
7311 and then Nkind
(Exp
) = N_Function_Call
7315 -- Remove side effects from the expression now so that other parts
7316 -- of the expander do not have to reanalyze this node without this
7319 Rewrite
(Exp
, Duplicate_Subexpr_No_Checks
(Exp
));
7321 -- For controlled types, do the allocation on the secondary stack
7322 -- manually in order to call adjust at the right time:
7324 -- type Anon1 is access R_Type;
7325 -- for Anon1'Storage_pool use ss_pool;
7326 -- Anon2 : anon1 := new R_Type'(expr);
7327 -- return Anon2.all;
7329 -- We do the same for classwide types that are not potentially
7330 -- controlled (by the virtue of restriction No_Finalization) because
7331 -- gigi is not able to properly allocate class-wide types.
7333 elsif CW_Or_Has_Controlled_Part
(Utyp
) then
7335 Loc
: constant Source_Ptr
:= Sloc
(N
);
7336 Acc_Typ
: constant Entity_Id
:= Make_Temporary
(Loc
, 'A');
7337 Alloc_Node
: Node_Id
;
7341 Set_Ekind
(Acc_Typ
, E_Access_Type
);
7343 Set_Associated_Storage_Pool
(Acc_Typ
, RTE
(RE_SS_Pool
));
7345 -- This is an allocator for the secondary stack, and it's fine
7346 -- to have Comes_From_Source set False on it, as gigi knows not
7347 -- to flag it as a violation of No_Implicit_Heap_Allocations.
7350 Make_Allocator
(Loc
,
7352 Make_Qualified_Expression
(Loc
,
7353 Subtype_Mark
=> New_Reference_To
(Etype
(Exp
), Loc
),
7354 Expression
=> Relocate_Node
(Exp
)));
7356 -- We do not want discriminant checks on the declaration,
7357 -- given that it gets its value from the allocator.
7359 Set_No_Initialization
(Alloc_Node
);
7361 Temp
:= Make_Temporary
(Loc
, 'R', Alloc_Node
);
7363 Insert_List_Before_And_Analyze
(N
, New_List
(
7364 Make_Full_Type_Declaration
(Loc
,
7365 Defining_Identifier
=> Acc_Typ
,
7367 Make_Access_To_Object_Definition
(Loc
,
7368 Subtype_Indication
=> Subtype_Ind
)),
7370 Make_Object_Declaration
(Loc
,
7371 Defining_Identifier
=> Temp
,
7372 Object_Definition
=> New_Reference_To
(Acc_Typ
, Loc
),
7373 Expression
=> Alloc_Node
)));
7376 Make_Explicit_Dereference
(Loc
,
7377 Prefix
=> New_Reference_To
(Temp
, Loc
)));
7379 -- Ada 2005 (AI-251): If the type of the returned object is
7380 -- an interface then add an implicit type conversion to force
7381 -- displacement of the "this" pointer.
7383 if Is_Interface
(R_Type
) then
7384 Rewrite
(Exp
, Convert_To
(R_Type
, Relocate_Node
(Exp
)));
7387 Analyze_And_Resolve
(Exp
, R_Type
);
7390 -- Otherwise use the gigi mechanism to allocate result on the
7394 Check_Restriction
(No_Secondary_Stack
, N
);
7395 Set_Storage_Pool
(N
, RTE
(RE_SS_Pool
));
7397 -- If we are generating code for the VM do not use
7398 -- SS_Allocate since everything is heap-allocated anyway.
7400 if VM_Target
= No_VM
then
7401 Set_Procedure_To_Call
(N
, RTE
(RE_SS_Allocate
));
7406 -- Implement the rules of 6.5(8-10), which require a tag check in
7407 -- the case of a limited tagged return type, and tag reassignment for
7408 -- nonlimited tagged results. These actions are needed when the return
7409 -- type is a specific tagged type and the result expression is a
7410 -- conversion or a formal parameter, because in that case the tag of
7411 -- the expression might differ from the tag of the specific result type.
7413 if Is_Tagged_Type
(Utyp
)
7414 and then not Is_Class_Wide_Type
(Utyp
)
7415 and then (Nkind_In
(Exp
, N_Type_Conversion
,
7416 N_Unchecked_Type_Conversion
)
7417 or else (Is_Entity_Name
(Exp
)
7418 and then Ekind
(Entity
(Exp
)) in Formal_Kind
))
7420 -- When the return type is limited, perform a check that the tag of
7421 -- the result is the same as the tag of the return type.
7423 if Is_Limited_Type
(R_Type
) then
7425 Make_Raise_Constraint_Error
(Loc
,
7429 Make_Selected_Component
(Loc
,
7430 Prefix
=> Duplicate_Subexpr
(Exp
),
7431 Selector_Name
=> Make_Identifier
(Loc
, Name_uTag
)),
7433 Make_Attribute_Reference
(Loc
,
7435 New_Occurrence_Of
(Base_Type
(Utyp
), Loc
),
7436 Attribute_Name
=> Name_Tag
)),
7437 Reason
=> CE_Tag_Check_Failed
));
7439 -- If the result type is a specific nonlimited tagged type, then we
7440 -- have to ensure that the tag of the result is that of the result
7441 -- type. This is handled by making a copy of the expression in
7442 -- the case where it might have a different tag, namely when the
7443 -- expression is a conversion or a formal parameter. We create a new
7444 -- object of the result type and initialize it from the expression,
7445 -- which will implicitly force the tag to be set appropriately.
7449 ExpR
: constant Node_Id
:= Relocate_Node
(Exp
);
7450 Result_Id
: constant Entity_Id
:=
7451 Make_Temporary
(Loc
, 'R', ExpR
);
7452 Result_Exp
: constant Node_Id
:=
7453 New_Reference_To
(Result_Id
, Loc
);
7454 Result_Obj
: constant Node_Id
:=
7455 Make_Object_Declaration
(Loc
,
7456 Defining_Identifier
=> Result_Id
,
7457 Object_Definition
=>
7458 New_Reference_To
(R_Type
, Loc
),
7459 Constant_Present
=> True,
7460 Expression
=> ExpR
);
7463 Set_Assignment_OK
(Result_Obj
);
7464 Insert_Action
(Exp
, Result_Obj
);
7466 Rewrite
(Exp
, Result_Exp
);
7467 Analyze_And_Resolve
(Exp
, R_Type
);
7471 -- Ada 2005 (AI-344): If the result type is class-wide, then insert
7472 -- a check that the level of the return expression's underlying type
7473 -- is not deeper than the level of the master enclosing the function.
7474 -- Always generate the check when the type of the return expression
7475 -- is class-wide, when it's a type conversion, or when it's a formal
7476 -- parameter. Otherwise, suppress the check in the case where the
7477 -- return expression has a specific type whose level is known not to
7478 -- be statically deeper than the function's result type.
7480 -- Note: accessibility check is skipped in the VM case, since there
7481 -- does not seem to be any practical way to implement this check.
7483 elsif Ada_Version
>= Ada_2005
7484 and then Tagged_Type_Expansion
7485 and then Is_Class_Wide_Type
(R_Type
)
7486 and then not Scope_Suppress
.Suppress
(Accessibility_Check
)
7488 (Is_Class_Wide_Type
(Etype
(Exp
))
7489 or else Nkind_In
(Exp
, N_Type_Conversion
,
7490 N_Unchecked_Type_Conversion
)
7491 or else (Is_Entity_Name
(Exp
)
7492 and then Ekind
(Entity
(Exp
)) in Formal_Kind
)
7493 or else Scope_Depth
(Enclosing_Dynamic_Scope
(Etype
(Exp
))) >
7494 Scope_Depth
(Enclosing_Dynamic_Scope
(Scope_Id
)))
7500 -- Ada 2005 (AI-251): In class-wide interface objects we displace
7501 -- "this" to reference the base of the object. This is required to
7502 -- get access to the TSD of the object.
7504 if Is_Class_Wide_Type
(Etype
(Exp
))
7505 and then Is_Interface
(Etype
(Exp
))
7506 and then Nkind
(Exp
) = N_Explicit_Dereference
7509 Make_Explicit_Dereference
(Loc
,
7511 Unchecked_Convert_To
(RTE
(RE_Tag_Ptr
),
7512 Make_Function_Call
(Loc
,
7514 New_Reference_To
(RTE
(RE_Base_Address
), Loc
),
7515 Parameter_Associations
=> New_List
(
7516 Unchecked_Convert_To
(RTE
(RE_Address
),
7517 Duplicate_Subexpr
(Prefix
(Exp
)))))));
7520 Make_Attribute_Reference
(Loc
,
7521 Prefix
=> Duplicate_Subexpr
(Exp
),
7522 Attribute_Name
=> Name_Tag
);
7526 Make_Raise_Program_Error
(Loc
,
7529 Left_Opnd
=> Build_Get_Access_Level
(Loc
, Tag_Node
),
7531 Make_Integer_Literal
(Loc
,
7532 Scope_Depth
(Enclosing_Dynamic_Scope
(Scope_Id
)))),
7533 Reason
=> PE_Accessibility_Check_Failed
));
7536 -- AI05-0073: If function has a controlling access result, check that
7537 -- the tag of the return value, if it is not null, matches designated
7538 -- type of return type.
7539 -- The return expression is referenced twice in the code below, so
7540 -- it must be made free of side effects. Given that different compilers
7541 -- may evaluate these parameters in different order, both occurrences
7544 elsif Ekind
(R_Type
) = E_Anonymous_Access_Type
7545 and then Has_Controlling_Result
(Scope_Id
)
7548 Make_Raise_Constraint_Error
(Loc
,
7553 Left_Opnd
=> Duplicate_Subexpr
(Exp
),
7554 Right_Opnd
=> Make_Null
(Loc
)),
7556 Right_Opnd
=> Make_Op_Ne
(Loc
,
7558 Make_Selected_Component
(Loc
,
7559 Prefix
=> Duplicate_Subexpr
(Exp
),
7560 Selector_Name
=> Make_Identifier
(Loc
, Name_uTag
)),
7563 Make_Attribute_Reference
(Loc
,
7565 New_Occurrence_Of
(Designated_Type
(R_Type
), Loc
),
7566 Attribute_Name
=> Name_Tag
))),
7568 Reason
=> CE_Tag_Check_Failed
),
7569 Suppress
=> All_Checks
);
7572 -- AI05-0234: RM 6.5(21/3). Check access discriminants to
7573 -- ensure that the function result does not outlive an
7574 -- object designated by one of it discriminants.
7576 if Present
(Extra_Accessibility_Of_Result
(Scope_Id
))
7577 and then Has_Unconstrained_Access_Discriminants
(R_Type
)
7580 Discrim_Source
: Node_Id
;
7582 procedure Check_Against_Result_Level
(Level
: Node_Id
);
7583 -- Check the given accessibility level against the level
7584 -- determined by the point of call. (AI05-0234).
7586 --------------------------------
7587 -- Check_Against_Result_Level --
7588 --------------------------------
7590 procedure Check_Against_Result_Level
(Level
: Node_Id
) is
7593 Make_Raise_Program_Error
(Loc
,
7599 (Extra_Accessibility_Of_Result
(Scope_Id
), Loc
)),
7600 Reason
=> PE_Accessibility_Check_Failed
));
7601 end Check_Against_Result_Level
;
7604 Discrim_Source
:= Exp
;
7605 while Nkind
(Discrim_Source
) = N_Qualified_Expression
loop
7606 Discrim_Source
:= Expression
(Discrim_Source
);
7609 if Nkind
(Discrim_Source
) = N_Identifier
7610 and then Is_Return_Object
(Entity
(Discrim_Source
))
7612 Discrim_Source
:= Entity
(Discrim_Source
);
7614 if Is_Constrained
(Etype
(Discrim_Source
)) then
7615 Discrim_Source
:= Etype
(Discrim_Source
);
7617 Discrim_Source
:= Expression
(Parent
(Discrim_Source
));
7620 elsif Nkind
(Discrim_Source
) = N_Identifier
7621 and then Nkind_In
(Original_Node
(Discrim_Source
),
7622 N_Aggregate
, N_Extension_Aggregate
)
7624 Discrim_Source
:= Original_Node
(Discrim_Source
);
7626 elsif Nkind
(Discrim_Source
) = N_Explicit_Dereference
and then
7627 Nkind
(Original_Node
(Discrim_Source
)) = N_Function_Call
7629 Discrim_Source
:= Original_Node
(Discrim_Source
);
7632 while Nkind_In
(Discrim_Source
, N_Qualified_Expression
,
7634 N_Unchecked_Type_Conversion
)
7636 Discrim_Source
:= Expression
(Discrim_Source
);
7639 case Nkind
(Discrim_Source
) is
7640 when N_Defining_Identifier
=>
7642 pragma Assert
(Is_Composite_Type
(Discrim_Source
)
7643 and then Has_Discriminants
(Discrim_Source
)
7644 and then Is_Constrained
(Discrim_Source
));
7647 Discrim
: Entity_Id
:=
7648 First_Discriminant
(Base_Type
(R_Type
));
7649 Disc_Elmt
: Elmt_Id
:=
7650 First_Elmt
(Discriminant_Constraint
7654 if Ekind
(Etype
(Discrim
)) =
7655 E_Anonymous_Access_Type
7657 Check_Against_Result_Level
7658 (Dynamic_Accessibility_Level
(Node
(Disc_Elmt
)));
7661 Next_Elmt
(Disc_Elmt
);
7662 Next_Discriminant
(Discrim
);
7663 exit when not Present
(Discrim
);
7667 when N_Aggregate | N_Extension_Aggregate
=>
7669 -- Unimplemented: extension aggregate case where discrims
7670 -- come from ancestor part, not extension part.
7673 Discrim
: Entity_Id
:=
7674 First_Discriminant
(Base_Type
(R_Type
));
7676 Disc_Exp
: Node_Id
:= Empty
;
7678 Positionals_Exhausted
7679 : Boolean := not Present
(Expressions
7682 function Associated_Expr
7683 (Comp_Id
: Entity_Id
;
7684 Associations
: List_Id
) return Node_Id
;
7686 -- Given a component and a component associations list,
7687 -- locate the expression for that component; returns
7688 -- Empty if no such expression is found.
7690 ---------------------
7691 -- Associated_Expr --
7692 ---------------------
7694 function Associated_Expr
7695 (Comp_Id
: Entity_Id
;
7696 Associations
: List_Id
) return Node_Id
7702 -- Simple linear search seems ok here
7704 Assoc
:= First
(Associations
);
7705 while Present
(Assoc
) loop
7706 Choice
:= First
(Choices
(Assoc
));
7707 while Present
(Choice
) loop
7708 if (Nkind
(Choice
) = N_Identifier
7709 and then Chars
(Choice
) = Chars
(Comp_Id
))
7710 or else (Nkind
(Choice
) = N_Others_Choice
)
7712 return Expression
(Assoc
);
7722 end Associated_Expr
;
7724 -- Start of processing for Expand_Simple_Function_Return
7727 if not Positionals_Exhausted
then
7728 Disc_Exp
:= First
(Expressions
(Discrim_Source
));
7732 if Positionals_Exhausted
then
7736 Component_Associations
(Discrim_Source
));
7739 if Ekind
(Etype
(Discrim
)) =
7740 E_Anonymous_Access_Type
7742 Check_Against_Result_Level
7743 (Dynamic_Accessibility_Level
(Disc_Exp
));
7746 Next_Discriminant
(Discrim
);
7747 exit when not Present
(Discrim
);
7749 if not Positionals_Exhausted
then
7751 Positionals_Exhausted
:= not Present
(Disc_Exp
);
7756 when N_Function_Call
=>
7758 -- No check needed (check performed by callee)
7765 Level
: constant Node_Id
:=
7766 Make_Integer_Literal
(Loc
,
7767 Object_Access_Level
(Discrim_Source
));
7770 -- Unimplemented: check for name prefix that includes
7771 -- a dereference of an access value with a dynamic
7772 -- accessibility level (e.g., an access param or a
7773 -- saooaaat) and use dynamic level in that case. For
7775 -- return Access_Param.all(Some_Index).Some_Component;
7778 Set_Etype
(Level
, Standard_Natural
);
7779 Check_Against_Result_Level
(Level
);
7786 -- If we are returning an object that may not be bit-aligned, then copy
7787 -- the value into a temporary first. This copy may need to expand to a
7788 -- loop of component operations.
7790 if Is_Possibly_Unaligned_Slice
(Exp
)
7791 or else Is_Possibly_Unaligned_Object
(Exp
)
7794 ExpR
: constant Node_Id
:= Relocate_Node
(Exp
);
7795 Tnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', ExpR
);
7798 Make_Object_Declaration
(Loc
,
7799 Defining_Identifier
=> Tnn
,
7800 Constant_Present
=> True,
7801 Object_Definition
=> New_Occurrence_Of
(R_Type
, Loc
),
7802 Expression
=> ExpR
),
7803 Suppress
=> All_Checks
);
7804 Rewrite
(Exp
, New_Occurrence_Of
(Tnn
, Loc
));
7808 -- Generate call to postcondition checks if they are present
7810 if Ekind
(Scope_Id
) = E_Function
7811 and then Has_Postconditions
(Scope_Id
)
7813 -- We are going to reference the returned value twice in this case,
7814 -- once in the call to _Postconditions, and once in the actual return
7815 -- statement, but we can't have side effects happening twice, and in
7816 -- any case for efficiency we don't want to do the computation twice.
7818 -- If the returned expression is an entity name, we don't need to
7819 -- worry since it is efficient and safe to reference it twice, that's
7820 -- also true for literals other than string literals, and for the
7821 -- case of X.all where X is an entity name.
7823 if Is_Entity_Name
(Exp
)
7824 or else Nkind_In
(Exp
, N_Character_Literal
,
7827 or else (Nkind
(Exp
) = N_Explicit_Dereference
7828 and then Is_Entity_Name
(Prefix
(Exp
)))
7832 -- Otherwise we are going to need a temporary to capture the value
7836 ExpR
: constant Node_Id
:= Relocate_Node
(Exp
);
7837 Tnn
: constant Entity_Id
:= Make_Temporary
(Loc
, 'T', ExpR
);
7840 -- For a complex expression of an elementary type, capture
7841 -- value in the temporary and use it as the reference.
7843 if Is_Elementary_Type
(R_Type
) then
7845 Make_Object_Declaration
(Loc
,
7846 Defining_Identifier
=> Tnn
,
7847 Constant_Present
=> True,
7848 Object_Definition
=> New_Occurrence_Of
(R_Type
, Loc
),
7849 Expression
=> ExpR
),
7850 Suppress
=> All_Checks
);
7852 Rewrite
(Exp
, New_Occurrence_Of
(Tnn
, Loc
));
7854 -- If we have something we can rename, generate a renaming of
7855 -- the object and replace the expression with a reference
7857 elsif Is_Object_Reference
(Exp
) then
7859 Make_Object_Renaming_Declaration
(Loc
,
7860 Defining_Identifier
=> Tnn
,
7861 Subtype_Mark
=> New_Occurrence_Of
(R_Type
, Loc
),
7863 Suppress
=> All_Checks
);
7865 Rewrite
(Exp
, New_Occurrence_Of
(Tnn
, Loc
));
7867 -- Otherwise we have something like a string literal or an
7868 -- aggregate. We could copy the value, but that would be
7869 -- inefficient. Instead we make a reference to the value and
7870 -- capture this reference with a renaming, the expression is
7871 -- then replaced by a dereference of this renaming.
7874 -- For now, copy the value, since the code below does not
7875 -- seem to work correctly ???
7878 Make_Object_Declaration
(Loc
,
7879 Defining_Identifier
=> Tnn
,
7880 Constant_Present
=> True,
7881 Object_Definition
=> New_Occurrence_Of
(R_Type
, Loc
),
7882 Expression
=> Relocate_Node
(Exp
)),
7883 Suppress
=> All_Checks
);
7885 Rewrite
(Exp
, New_Occurrence_Of
(Tnn
, Loc
));
7887 -- Insert_Action (Exp,
7888 -- Make_Object_Renaming_Declaration (Loc,
7889 -- Defining_Identifier => Tnn,
7890 -- Access_Definition =>
7891 -- Make_Access_Definition (Loc,
7892 -- All_Present => True,
7893 -- Subtype_Mark => New_Occurrence_Of (R_Type, Loc)),
7895 -- Make_Reference (Loc,
7896 -- Prefix => Relocate_Node (Exp))),
7897 -- Suppress => All_Checks);
7900 -- Make_Explicit_Dereference (Loc,
7901 -- Prefix => New_Occurrence_Of (Tnn, Loc)));
7906 -- Generate call to _postconditions
7909 Make_Procedure_Call_Statement
(Loc
,
7910 Name
=> Make_Identifier
(Loc
, Name_uPostconditions
),
7911 Parameter_Associations
=> New_List
(Duplicate_Subexpr
(Exp
))));
7914 -- Ada 2005 (AI-251): If this return statement corresponds with an
7915 -- simple return statement associated with an extended return statement
7916 -- and the type of the returned object is an interface then generate an
7917 -- implicit conversion to force displacement of the "this" pointer.
7919 if Ada_Version
>= Ada_2005
7920 and then Comes_From_Extended_Return_Statement
(N
)
7921 and then Nkind
(Expression
(N
)) = N_Identifier
7922 and then Is_Interface
(Utyp
)
7923 and then Utyp
/= Underlying_Type
(Exptyp
)
7925 Rewrite
(Exp
, Convert_To
(Utyp
, Relocate_Node
(Exp
)));
7926 Analyze_And_Resolve
(Exp
);
7928 end Expand_Simple_Function_Return
;
7930 --------------------------------
7931 -- Is_Build_In_Place_Function --
7932 --------------------------------
7934 function Is_Build_In_Place_Function
(E
: Entity_Id
) return Boolean is
7936 -- This function is called from Expand_Subtype_From_Expr during
7937 -- semantic analysis, even when expansion is off. In those cases
7938 -- the build_in_place expansion will not take place.
7940 if not Expander_Active
then
7944 -- For now we test whether E denotes a function or access-to-function
7945 -- type whose result subtype is inherently limited. Later this test may
7946 -- be revised to allow composite nonlimited types. Functions with a
7947 -- foreign convention or whose result type has a foreign convention
7950 if Ekind_In
(E
, E_Function
, E_Generic_Function
)
7951 or else (Ekind
(E
) = E_Subprogram_Type
7952 and then Etype
(E
) /= Standard_Void_Type
)
7954 -- Note: If you have Convention (C) on an inherently limited type,
7955 -- you're on your own. That is, the C code will have to be carefully
7956 -- written to know about the Ada conventions.
7958 if Has_Foreign_Convention
(E
)
7959 or else Has_Foreign_Convention
(Etype
(E
))
7963 -- In Ada 2005 all functions with an inherently limited return type
7964 -- must be handled using a build-in-place profile, including the case
7965 -- of a function with a limited interface result, where the function
7966 -- may return objects of nonlimited descendants.
7969 return Is_Immutably_Limited_Type
(Etype
(E
))
7970 and then Ada_Version
>= Ada_2005
7971 and then not Debug_Flag_Dot_L
;
7977 end Is_Build_In_Place_Function
;
7979 -------------------------------------
7980 -- Is_Build_In_Place_Function_Call --
7981 -------------------------------------
7983 function Is_Build_In_Place_Function_Call
(N
: Node_Id
) return Boolean is
7984 Exp_Node
: Node_Id
:= N
;
7985 Function_Id
: Entity_Id
;
7988 -- Return False when the expander is inactive, since awareness of
7989 -- build-in-place treatment is only relevant during expansion. Note that
7990 -- Is_Build_In_Place_Function, which is called as part of this function,
7991 -- is also conditioned this way, but we need to check here as well to
7992 -- avoid blowing up on processing protected calls when expansion is
7993 -- disabled (such as with -gnatc) since those would trip over the raise
7994 -- of Program_Error below.
7996 if not Expander_Active
then
8000 -- Step past qualification or unchecked conversion (the latter can occur
8001 -- in cases of calls to 'Input).
8003 if Nkind_In
(Exp_Node
, N_Qualified_Expression
,
8004 N_Unchecked_Type_Conversion
)
8006 Exp_Node
:= Expression
(N
);
8009 if Nkind
(Exp_Node
) /= N_Function_Call
then
8013 -- In Alfa mode, build-in-place calls are not expanded, so that we
8014 -- may end up with a call that is neither resolved to an entity, nor
8015 -- an indirect call.
8020 elsif Is_Entity_Name
(Name
(Exp_Node
)) then
8021 Function_Id
:= Entity
(Name
(Exp_Node
));
8023 -- In the case of an explicitly dereferenced call, use the subprogram
8024 -- type generated for the dereference.
8026 elsif Nkind
(Name
(Exp_Node
)) = N_Explicit_Dereference
then
8027 Function_Id
:= Etype
(Name
(Exp_Node
));
8030 raise Program_Error
;
8033 return Is_Build_In_Place_Function
(Function_Id
);
8035 end Is_Build_In_Place_Function_Call
;
8037 -----------------------
8038 -- Freeze_Subprogram --
8039 -----------------------
8041 procedure Freeze_Subprogram
(N
: Node_Id
) is
8042 Loc
: constant Source_Ptr
:= Sloc
(N
);
8044 procedure Register_Predefined_DT_Entry
(Prim
: Entity_Id
);
8045 -- (Ada 2005): Register a predefined primitive in all the secondary
8046 -- dispatch tables of its primitive type.
8048 ----------------------------------
8049 -- Register_Predefined_DT_Entry --
8050 ----------------------------------
8052 procedure Register_Predefined_DT_Entry
(Prim
: Entity_Id
) is
8053 Iface_DT_Ptr
: Elmt_Id
;
8054 Tagged_Typ
: Entity_Id
;
8055 Thunk_Id
: Entity_Id
;
8056 Thunk_Code
: Node_Id
;
8059 Tagged_Typ
:= Find_Dispatching_Type
(Prim
);
8061 if No
(Access_Disp_Table
(Tagged_Typ
))
8062 or else not Has_Interfaces
(Tagged_Typ
)
8063 or else not RTE_Available
(RE_Interface_Tag
)
8064 or else Restriction_Active
(No_Dispatching_Calls
)
8069 -- Skip the first two access-to-dispatch-table pointers since they
8070 -- leads to the primary dispatch table (predefined DT and user
8071 -- defined DT). We are only concerned with the secondary dispatch
8072 -- table pointers. Note that the access-to- dispatch-table pointer
8073 -- corresponds to the first implemented interface retrieved below.
8076 Next_Elmt
(Next_Elmt
(First_Elmt
(Access_Disp_Table
(Tagged_Typ
))));
8078 while Present
(Iface_DT_Ptr
)
8079 and then Ekind
(Node
(Iface_DT_Ptr
)) = E_Constant
8081 pragma Assert
(Has_Thunks
(Node
(Iface_DT_Ptr
)));
8082 Expand_Interface_Thunk
(Prim
, Thunk_Id
, Thunk_Code
);
8084 if Present
(Thunk_Code
) then
8085 Insert_Actions_After
(N
, New_List
(
8088 Build_Set_Predefined_Prim_Op_Address
(Loc
,
8090 New_Reference_To
(Node
(Next_Elmt
(Iface_DT_Ptr
)), Loc
),
8091 Position
=> DT_Position
(Prim
),
8093 Unchecked_Convert_To
(RTE
(RE_Prim_Ptr
),
8094 Make_Attribute_Reference
(Loc
,
8095 Prefix
=> New_Reference_To
(Thunk_Id
, Loc
),
8096 Attribute_Name
=> Name_Unrestricted_Access
))),
8098 Build_Set_Predefined_Prim_Op_Address
(Loc
,
8101 (Node
(Next_Elmt
(Next_Elmt
(Next_Elmt
(Iface_DT_Ptr
)))),
8103 Position
=> DT_Position
(Prim
),
8105 Unchecked_Convert_To
(RTE
(RE_Prim_Ptr
),
8106 Make_Attribute_Reference
(Loc
,
8107 Prefix
=> New_Reference_To
(Prim
, Loc
),
8108 Attribute_Name
=> Name_Unrestricted_Access
)))));
8111 -- Skip the tag of the predefined primitives dispatch table
8113 Next_Elmt
(Iface_DT_Ptr
);
8114 pragma Assert
(Has_Thunks
(Node
(Iface_DT_Ptr
)));
8116 -- Skip tag of the no-thunks dispatch table
8118 Next_Elmt
(Iface_DT_Ptr
);
8119 pragma Assert
(not Has_Thunks
(Node
(Iface_DT_Ptr
)));
8121 -- Skip tag of predefined primitives no-thunks dispatch table
8123 Next_Elmt
(Iface_DT_Ptr
);
8124 pragma Assert
(not Has_Thunks
(Node
(Iface_DT_Ptr
)));
8126 Next_Elmt
(Iface_DT_Ptr
);
8128 end Register_Predefined_DT_Entry
;
8132 Subp
: constant Entity_Id
:= Entity
(N
);
8134 -- Start of processing for Freeze_Subprogram
8137 -- We suppress the initialization of the dispatch table entry when
8138 -- VM_Target because the dispatching mechanism is handled internally
8141 if Is_Dispatching_Operation
(Subp
)
8142 and then not Is_Abstract_Subprogram
(Subp
)
8143 and then Present
(DTC_Entity
(Subp
))
8144 and then Present
(Scope
(DTC_Entity
(Subp
)))
8145 and then Tagged_Type_Expansion
8146 and then not Restriction_Active
(No_Dispatching_Calls
)
8147 and then RTE_Available
(RE_Tag
)
8150 Typ
: constant Entity_Id
:= Scope
(DTC_Entity
(Subp
));
8153 -- Handle private overridden primitives
8155 if not Is_CPP_Class
(Typ
) then
8156 Check_Overriding_Operation
(Subp
);
8159 -- We assume that imported CPP primitives correspond with objects
8160 -- whose constructor is in the CPP side; therefore we don't need
8161 -- to generate code to register them in the dispatch table.
8163 if Is_CPP_Class
(Typ
) then
8166 -- Handle CPP primitives found in derivations of CPP_Class types.
8167 -- These primitives must have been inherited from some parent, and
8168 -- there is no need to register them in the dispatch table because
8169 -- Build_Inherit_Prims takes care of the initialization of these
8172 elsif Is_Imported
(Subp
)
8173 and then (Convention
(Subp
) = Convention_CPP
8174 or else Convention
(Subp
) = Convention_C
)
8178 -- Generate code to register the primitive in non statically
8179 -- allocated dispatch tables
8181 elsif not Building_Static_DT
(Scope
(DTC_Entity
(Subp
))) then
8183 -- When a primitive is frozen, enter its name in its dispatch
8186 if not Is_Interface
(Typ
)
8187 or else Present
(Interface_Alias
(Subp
))
8189 if Is_Predefined_Dispatching_Operation
(Subp
) then
8190 Register_Predefined_DT_Entry
(Subp
);
8193 Insert_Actions_After
(N
,
8194 Register_Primitive
(Loc
, Prim
=> Subp
));
8200 -- Mark functions that return by reference. Note that it cannot be part
8201 -- of the normal semantic analysis of the spec since the underlying
8202 -- returned type may not be known yet (for private types).
8205 Typ
: constant Entity_Id
:= Etype
(Subp
);
8206 Utyp
: constant Entity_Id
:= Underlying_Type
(Typ
);
8208 if Is_Immutably_Limited_Type
(Typ
) then
8209 Set_Returns_By_Ref
(Subp
);
8210 elsif Present
(Utyp
) and then CW_Or_Has_Controlled_Part
(Utyp
) then
8211 Set_Returns_By_Ref
(Subp
);
8214 end Freeze_Subprogram
;
8216 -----------------------
8217 -- Is_Null_Procedure --
8218 -----------------------
8220 function Is_Null_Procedure
(Subp
: Entity_Id
) return Boolean is
8221 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Subp
);
8224 if Ekind
(Subp
) /= E_Procedure
then
8227 -- Check if this is a declared null procedure
8229 elsif Nkind
(Decl
) = N_Subprogram_Declaration
then
8230 if not Null_Present
(Specification
(Decl
)) then
8233 elsif No
(Body_To_Inline
(Decl
)) then
8236 -- Check if the body contains only a null statement, followed by
8237 -- the return statement added during expansion.
8241 Orig_Bod
: constant Node_Id
:= Body_To_Inline
(Decl
);
8247 if Nkind
(Orig_Bod
) /= N_Subprogram_Body
then
8250 -- We must skip SCIL nodes because they are currently
8251 -- implemented as special N_Null_Statement nodes.
8255 (Statements
(Handled_Statement_Sequence
(Orig_Bod
)));
8256 Stat2
:= Next_Non_SCIL_Node
(Stat
);
8259 Is_Empty_List
(Declarations
(Orig_Bod
))
8260 and then Nkind
(Stat
) = N_Null_Statement
8264 (Nkind
(Stat2
) = N_Simple_Return_Statement
8265 and then No
(Next
(Stat2
))));
8273 end Is_Null_Procedure
;
8275 -------------------------------------------
8276 -- Make_Build_In_Place_Call_In_Allocator --
8277 -------------------------------------------
8279 procedure Make_Build_In_Place_Call_In_Allocator
8280 (Allocator
: Node_Id
;
8281 Function_Call
: Node_Id
)
8283 Acc_Type
: constant Entity_Id
:= Etype
(Allocator
);
8285 Func_Call
: Node_Id
:= Function_Call
;
8286 Function_Id
: Entity_Id
;
8287 Result_Subt
: Entity_Id
;
8288 New_Allocator
: Node_Id
;
8289 Return_Obj_Access
: Entity_Id
;
8292 -- Step past qualification or unchecked conversion (the latter can occur
8293 -- in cases of calls to 'Input).
8295 if Nkind_In
(Func_Call
,
8296 N_Qualified_Expression
,
8297 N_Unchecked_Type_Conversion
)
8299 Func_Call
:= Expression
(Func_Call
);
8302 -- If the call has already been processed to add build-in-place actuals
8303 -- then return. This should not normally occur in an allocator context,
8304 -- but we add the protection as a defensive measure.
8306 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8310 -- Mark the call as processed as a build-in-place call
8312 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8314 Loc
:= Sloc
(Function_Call
);
8316 if Is_Entity_Name
(Name
(Func_Call
)) then
8317 Function_Id
:= Entity
(Name
(Func_Call
));
8319 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8320 Function_Id
:= Etype
(Name
(Func_Call
));
8323 raise Program_Error
;
8326 Result_Subt
:= Available_View
(Etype
(Function_Id
));
8328 -- Check whether return type includes tasks. This may not have been done
8329 -- previously, if the type was a limited view.
8331 if Has_Task
(Result_Subt
) then
8332 Build_Activation_Chain_Entity
(Allocator
);
8335 -- When the result subtype is constrained, the return object must be
8336 -- allocated on the caller side, and access to it is passed to the
8339 -- Here and in related routines, we must examine the full view of the
8340 -- type, because the view at the point of call may differ from that
8341 -- that in the function body, and the expansion mechanism depends on
8342 -- the characteristics of the full view.
8344 if Is_Constrained
(Underlying_Type
(Result_Subt
)) then
8346 -- Replace the initialized allocator of form "new T'(Func (...))"
8347 -- with an uninitialized allocator of form "new T", where T is the
8348 -- result subtype of the called function. The call to the function
8349 -- is handled separately further below.
8352 Make_Allocator
(Loc
,
8353 Expression
=> New_Reference_To
(Result_Subt
, Loc
));
8354 Set_No_Initialization
(New_Allocator
);
8356 -- Copy attributes to new allocator. Note that the new allocator
8357 -- logically comes from source if the original one did, so copy the
8358 -- relevant flag. This ensures proper treatment of the restriction
8359 -- No_Implicit_Heap_Allocations in this case.
8361 Set_Storage_Pool
(New_Allocator
, Storage_Pool
(Allocator
));
8362 Set_Procedure_To_Call
(New_Allocator
, Procedure_To_Call
(Allocator
));
8363 Set_Comes_From_Source
(New_Allocator
, Comes_From_Source
(Allocator
));
8365 Rewrite
(Allocator
, New_Allocator
);
8367 -- Create a new access object and initialize it to the result of the
8368 -- new uninitialized allocator. Note: we do not use Allocator as the
8369 -- Related_Node of Return_Obj_Access in call to Make_Temporary below
8370 -- as this would create a sort of infinite "recursion".
8372 Return_Obj_Access
:= Make_Temporary
(Loc
, 'R');
8373 Set_Etype
(Return_Obj_Access
, Acc_Type
);
8375 Insert_Action
(Allocator
,
8376 Make_Object_Declaration
(Loc
,
8377 Defining_Identifier
=> Return_Obj_Access
,
8378 Object_Definition
=> New_Reference_To
(Acc_Type
, Loc
),
8379 Expression
=> Relocate_Node
(Allocator
)));
8381 -- When the function has a controlling result, an allocation-form
8382 -- parameter must be passed indicating that the caller is allocating
8383 -- the result object. This is needed because such a function can be
8384 -- called as a dispatching operation and must be treated similarly
8385 -- to functions with unconstrained result subtypes.
8387 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8388 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8390 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8391 (Func_Call
, Function_Id
, Acc_Type
);
8393 Add_Task_Actuals_To_Build_In_Place_Call
8394 (Func_Call
, Function_Id
, Master_Actual
=> Master_Id
(Acc_Type
));
8396 -- Add an implicit actual to the function call that provides access
8397 -- to the allocated object. An unchecked conversion to the (specific)
8398 -- result subtype of the function is inserted to handle cases where
8399 -- the access type of the allocator has a class-wide designated type.
8401 Add_Access_Actual_To_Build_In_Place_Call
8404 Make_Unchecked_Type_Conversion
(Loc
,
8405 Subtype_Mark
=> New_Reference_To
(Result_Subt
, Loc
),
8407 Make_Explicit_Dereference
(Loc
,
8408 Prefix
=> New_Reference_To
(Return_Obj_Access
, Loc
))));
8410 -- When the result subtype is unconstrained, the function itself must
8411 -- perform the allocation of the return object, so we pass parameters
8412 -- indicating that. We don't yet handle the case where the allocation
8413 -- must be done in a user-defined storage pool, which will require
8414 -- passing another actual or two to provide allocation/deallocation
8418 -- Case of a user-defined storage pool. Pass an allocation parameter
8419 -- indicating that the function should allocate its result in the
8420 -- pool, and pass the pool. Use 'Unrestricted_Access because the
8421 -- pool may not be aliased.
8423 if VM_Target
= No_VM
8424 and then Present
(Associated_Storage_Pool
(Acc_Type
))
8426 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8427 (Func_Call
, Function_Id
, Alloc_Form
=> User_Storage_Pool
,
8429 Make_Attribute_Reference
(Loc
,
8432 (Associated_Storage_Pool
(Acc_Type
), Loc
),
8433 Attribute_Name
=> Name_Unrestricted_Access
));
8435 -- No user-defined pool; pass an allocation parameter indicating that
8436 -- the function should allocate its result on the heap.
8439 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8440 (Func_Call
, Function_Id
, Alloc_Form
=> Global_Heap
);
8443 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8444 (Func_Call
, Function_Id
, Acc_Type
);
8446 Add_Task_Actuals_To_Build_In_Place_Call
8447 (Func_Call
, Function_Id
, Master_Actual
=> Master_Id
(Acc_Type
));
8449 -- The caller does not provide the return object in this case, so we
8450 -- have to pass null for the object access actual.
8452 Add_Access_Actual_To_Build_In_Place_Call
8453 (Func_Call
, Function_Id
, Return_Object
=> Empty
);
8456 -- If the build-in-place function call returns a controlled object,
8457 -- the finalization master will require a reference to routine
8458 -- Finalize_Address of the designated type. Setting this attribute
8459 -- is done in the same manner to expansion of allocators.
8461 if Needs_Finalization
(Result_Subt
) then
8463 -- Controlled types with supressed finalization do not need to
8464 -- associate the address of their Finalize_Address primitives with
8465 -- a master since they do not need a master to begin with.
8467 if Is_Library_Level_Entity
(Acc_Type
)
8468 and then Finalize_Storage_Only
(Result_Subt
)
8472 -- Do not generate the call to Set_Finalize_Address in Alfa mode
8473 -- because it is not necessary and results in unwanted expansion.
8474 -- This expansion is also not carried out in CodePeer mode because
8475 -- Finalize_Address is never built.
8478 and then not CodePeer_Mode
8480 Insert_Action
(Allocator
,
8481 Make_Set_Finalize_Address_Call
(Loc
,
8482 Typ
=> Etype
(Function_Id
),
8483 Ptr_Typ
=> Acc_Type
));
8487 -- Finally, replace the allocator node with a reference to the result
8488 -- of the function call itself (which will effectively be an access
8489 -- to the object created by the allocator).
8491 Rewrite
(Allocator
, Make_Reference
(Loc
, Relocate_Node
(Function_Call
)));
8493 -- Ada 2005 (AI-251): If the type of the allocator is an interface then
8494 -- generate an implicit conversion to force displacement of the "this"
8497 if Is_Interface
(Designated_Type
(Acc_Type
)) then
8498 Rewrite
(Allocator
, Convert_To
(Acc_Type
, Relocate_Node
(Allocator
)));
8501 Analyze_And_Resolve
(Allocator
, Acc_Type
);
8502 end Make_Build_In_Place_Call_In_Allocator
;
8504 ---------------------------------------------------
8505 -- Make_Build_In_Place_Call_In_Anonymous_Context --
8506 ---------------------------------------------------
8508 procedure Make_Build_In_Place_Call_In_Anonymous_Context
8509 (Function_Call
: Node_Id
)
8512 Func_Call
: Node_Id
:= Function_Call
;
8513 Function_Id
: Entity_Id
;
8514 Result_Subt
: Entity_Id
;
8515 Return_Obj_Id
: Entity_Id
;
8516 Return_Obj_Decl
: Entity_Id
;
8519 -- Step past qualification or unchecked conversion (the latter can occur
8520 -- in cases of calls to 'Input).
8522 if Nkind_In
(Func_Call
, N_Qualified_Expression
,
8523 N_Unchecked_Type_Conversion
)
8525 Func_Call
:= Expression
(Func_Call
);
8528 -- If the call has already been processed to add build-in-place actuals
8529 -- then return. One place this can occur is for calls to build-in-place
8530 -- functions that occur within a call to a protected operation, where
8531 -- due to rewriting and expansion of the protected call there can be
8532 -- more than one call to Expand_Actuals for the same set of actuals.
8534 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8538 -- Mark the call as processed as a build-in-place call
8540 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8542 Loc
:= Sloc
(Function_Call
);
8544 if Is_Entity_Name
(Name
(Func_Call
)) then
8545 Function_Id
:= Entity
(Name
(Func_Call
));
8547 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8548 Function_Id
:= Etype
(Name
(Func_Call
));
8551 raise Program_Error
;
8554 Result_Subt
:= Etype
(Function_Id
);
8556 -- If the build-in-place function returns a controlled object, then the
8557 -- object needs to be finalized immediately after the context. Since
8558 -- this case produces a transient scope, the servicing finalizer needs
8559 -- to name the returned object. Create a temporary which is initialized
8560 -- with the function call:
8562 -- Temp_Id : Func_Type := BIP_Func_Call;
8564 -- The initialization expression of the temporary will be rewritten by
8565 -- the expander using the appropriate mechanism in Make_Build_In_Place_
8566 -- Call_In_Object_Declaration.
8568 if Needs_Finalization
(Result_Subt
) then
8570 Temp_Id
: constant Entity_Id
:= Make_Temporary
(Loc
, 'R');
8571 Temp_Decl
: Node_Id
;
8574 -- Reset the guard on the function call since the following does
8575 -- not perform actual call expansion.
8577 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
, False);
8580 Make_Object_Declaration
(Loc
,
8581 Defining_Identifier
=> Temp_Id
,
8582 Object_Definition
=>
8583 New_Reference_To
(Result_Subt
, Loc
),
8585 New_Copy_Tree
(Function_Call
));
8587 Insert_Action
(Function_Call
, Temp_Decl
);
8589 Rewrite
(Function_Call
, New_Reference_To
(Temp_Id
, Loc
));
8590 Analyze
(Function_Call
);
8593 -- When the result subtype is constrained, an object of the subtype is
8594 -- declared and an access value designating it is passed as an actual.
8596 elsif Is_Constrained
(Underlying_Type
(Result_Subt
)) then
8598 -- Create a temporary object to hold the function result
8600 Return_Obj_Id
:= Make_Temporary
(Loc
, 'R');
8601 Set_Etype
(Return_Obj_Id
, Result_Subt
);
8604 Make_Object_Declaration
(Loc
,
8605 Defining_Identifier
=> Return_Obj_Id
,
8606 Aliased_Present
=> True,
8607 Object_Definition
=> New_Reference_To
(Result_Subt
, Loc
));
8609 Set_No_Initialization
(Return_Obj_Decl
);
8611 Insert_Action
(Func_Call
, Return_Obj_Decl
);
8613 -- When the function has a controlling result, an allocation-form
8614 -- parameter must be passed indicating that the caller is allocating
8615 -- the result object. This is needed because such a function can be
8616 -- called as a dispatching operation and must be treated similarly
8617 -- to functions with unconstrained result subtypes.
8619 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8620 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8622 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8623 (Func_Call
, Function_Id
);
8625 Add_Task_Actuals_To_Build_In_Place_Call
8626 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8628 -- Add an implicit actual to the function call that provides access
8629 -- to the caller's return object.
8631 Add_Access_Actual_To_Build_In_Place_Call
8632 (Func_Call
, Function_Id
, New_Reference_To
(Return_Obj_Id
, Loc
));
8634 -- When the result subtype is unconstrained, the function must allocate
8635 -- the return object in the secondary stack, so appropriate implicit
8636 -- parameters are added to the call to indicate that. A transient
8637 -- scope is established to ensure eventual cleanup of the result.
8640 -- Pass an allocation parameter indicating that the function should
8641 -- allocate its result on the secondary stack.
8643 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8644 (Func_Call
, Function_Id
, Alloc_Form
=> Secondary_Stack
);
8646 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8647 (Func_Call
, Function_Id
);
8649 Add_Task_Actuals_To_Build_In_Place_Call
8650 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8652 -- Pass a null value to the function since no return object is
8653 -- available on the caller side.
8655 Add_Access_Actual_To_Build_In_Place_Call
8656 (Func_Call
, Function_Id
, Empty
);
8658 end Make_Build_In_Place_Call_In_Anonymous_Context
;
8660 --------------------------------------------
8661 -- Make_Build_In_Place_Call_In_Assignment --
8662 --------------------------------------------
8664 procedure Make_Build_In_Place_Call_In_Assignment
8666 Function_Call
: Node_Id
)
8668 Lhs
: constant Node_Id
:= Name
(Assign
);
8669 Func_Call
: Node_Id
:= Function_Call
;
8670 Func_Id
: Entity_Id
;
8674 Ptr_Typ
: Entity_Id
;
8675 Ptr_Typ_Decl
: Node_Id
;
8677 Result_Subt
: Entity_Id
;
8681 -- Step past qualification or unchecked conversion (the latter can occur
8682 -- in cases of calls to 'Input).
8684 if Nkind_In
(Func_Call
, N_Qualified_Expression
,
8685 N_Unchecked_Type_Conversion
)
8687 Func_Call
:= Expression
(Func_Call
);
8690 -- If the call has already been processed to add build-in-place actuals
8691 -- then return. This should not normally occur in an assignment context,
8692 -- but we add the protection as a defensive measure.
8694 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8698 -- Mark the call as processed as a build-in-place call
8700 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8702 Loc
:= Sloc
(Function_Call
);
8704 if Is_Entity_Name
(Name
(Func_Call
)) then
8705 Func_Id
:= Entity
(Name
(Func_Call
));
8707 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8708 Func_Id
:= Etype
(Name
(Func_Call
));
8711 raise Program_Error
;
8714 Result_Subt
:= Etype
(Func_Id
);
8716 -- When the result subtype is unconstrained, an additional actual must
8717 -- be passed to indicate that the caller is providing the return object.
8718 -- This parameter must also be passed when the called function has a
8719 -- controlling result, because dispatching calls to the function needs
8720 -- to be treated effectively the same as calls to class-wide functions.
8722 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8723 (Func_Call
, Func_Id
, Alloc_Form
=> Caller_Allocation
);
8725 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8726 (Func_Call
, Func_Id
);
8728 Add_Task_Actuals_To_Build_In_Place_Call
8729 (Func_Call
, Func_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8731 -- Add an implicit actual to the function call that provides access to
8732 -- the caller's return object.
8734 Add_Access_Actual_To_Build_In_Place_Call
8737 Make_Unchecked_Type_Conversion
(Loc
,
8738 Subtype_Mark
=> New_Reference_To
(Result_Subt
, Loc
),
8739 Expression
=> Relocate_Node
(Lhs
)));
8741 -- Create an access type designating the function's result subtype
8743 Ptr_Typ
:= Make_Temporary
(Loc
, 'A');
8746 Make_Full_Type_Declaration
(Loc
,
8747 Defining_Identifier
=> Ptr_Typ
,
8749 Make_Access_To_Object_Definition
(Loc
,
8750 All_Present
=> True,
8751 Subtype_Indication
=>
8752 New_Reference_To
(Result_Subt
, Loc
)));
8753 Insert_After_And_Analyze
(Assign
, Ptr_Typ_Decl
);
8755 -- Finally, create an access object initialized to a reference to the
8756 -- function call. We know this access value is non-null, so mark the
8757 -- entity accordingly to suppress junk access checks.
8759 New_Expr
:= Make_Reference
(Loc
, Relocate_Node
(Func_Call
));
8761 Obj_Id
:= Make_Temporary
(Loc
, 'R', New_Expr
);
8762 Set_Etype
(Obj_Id
, Ptr_Typ
);
8763 Set_Is_Known_Non_Null
(Obj_Id
);
8766 Make_Object_Declaration
(Loc
,
8767 Defining_Identifier
=> Obj_Id
,
8768 Object_Definition
=> New_Reference_To
(Ptr_Typ
, Loc
),
8769 Expression
=> New_Expr
);
8770 Insert_After_And_Analyze
(Ptr_Typ_Decl
, Obj_Decl
);
8772 Rewrite
(Assign
, Make_Null_Statement
(Loc
));
8774 -- Retrieve the target of the assignment
8776 if Nkind
(Lhs
) = N_Selected_Component
then
8777 Target
:= Selector_Name
(Lhs
);
8778 elsif Nkind
(Lhs
) = N_Type_Conversion
then
8779 Target
:= Expression
(Lhs
);
8784 -- If we are assigning to a return object or this is an expression of
8785 -- an extension aggregate, the target should either be an identifier
8786 -- or a simple expression. All other cases imply a different scenario.
8788 if Nkind
(Target
) in N_Has_Entity
then
8789 Target
:= Entity
(Target
);
8793 end Make_Build_In_Place_Call_In_Assignment
;
8795 ----------------------------------------------------
8796 -- Make_Build_In_Place_Call_In_Object_Declaration --
8797 ----------------------------------------------------
8799 procedure Make_Build_In_Place_Call_In_Object_Declaration
8800 (Object_Decl
: Node_Id
;
8801 Function_Call
: Node_Id
)
8804 Obj_Def_Id
: constant Entity_Id
:=
8805 Defining_Identifier
(Object_Decl
);
8806 Enclosing_Func
: constant Entity_Id
:=
8807 Enclosing_Subprogram
(Obj_Def_Id
);
8808 Call_Deref
: Node_Id
;
8809 Caller_Object
: Node_Id
;
8811 Fmaster_Actual
: Node_Id
:= Empty
;
8812 Func_Call
: Node_Id
:= Function_Call
;
8813 Function_Id
: Entity_Id
;
8814 Pool_Actual
: Node_Id
;
8815 Ptr_Typ_Decl
: Node_Id
;
8816 Pass_Caller_Acc
: Boolean := False;
8818 Ref_Type
: Entity_Id
;
8819 Result_Subt
: Entity_Id
;
8822 -- Step past qualification or unchecked conversion (the latter can occur
8823 -- in cases of calls to 'Input).
8825 if Nkind_In
(Func_Call
, N_Qualified_Expression
,
8826 N_Unchecked_Type_Conversion
)
8828 Func_Call
:= Expression
(Func_Call
);
8831 -- If the call has already been processed to add build-in-place actuals
8832 -- then return. This should not normally occur in an object declaration,
8833 -- but we add the protection as a defensive measure.
8835 if Is_Expanded_Build_In_Place_Call
(Func_Call
) then
8839 -- Mark the call as processed as a build-in-place call
8841 Set_Is_Expanded_Build_In_Place_Call
(Func_Call
);
8843 Loc
:= Sloc
(Function_Call
);
8845 if Is_Entity_Name
(Name
(Func_Call
)) then
8846 Function_Id
:= Entity
(Name
(Func_Call
));
8848 elsif Nkind
(Name
(Func_Call
)) = N_Explicit_Dereference
then
8849 Function_Id
:= Etype
(Name
(Func_Call
));
8852 raise Program_Error
;
8855 Result_Subt
:= Etype
(Function_Id
);
8857 -- If the the object is a return object of an enclosing build-in-place
8858 -- function, then the implicit build-in-place parameters of the
8859 -- enclosing function are simply passed along to the called function.
8860 -- (Unfortunately, this won't cover the case of extension aggregates
8861 -- where the ancestor part is a build-in-place unconstrained function
8862 -- call that should be passed along the caller's parameters. Currently
8863 -- those get mishandled by reassigning the result of the call to the
8864 -- aggregate return object, when the call result should really be
8865 -- directly built in place in the aggregate and not in a temporary. ???)
8867 if Is_Return_Object
(Defining_Identifier
(Object_Decl
)) then
8868 Pass_Caller_Acc
:= True;
8870 -- When the enclosing function has a BIP_Alloc_Form formal then we
8871 -- pass it along to the callee (such as when the enclosing function
8872 -- has an unconstrained or tagged result type).
8874 if Needs_BIP_Alloc_Form
(Enclosing_Func
) then
8875 if VM_Target
= No_VM
and then
8876 RTE_Available
(RE_Root_Storage_Pool_Ptr
)
8879 New_Reference_To
(Build_In_Place_Formal
8880 (Enclosing_Func
, BIP_Storage_Pool
), Loc
);
8882 -- The build-in-place pool formal is not built on .NET/JVM
8885 Pool_Actual
:= Empty
;
8888 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8893 (Build_In_Place_Formal
(Enclosing_Func
, BIP_Alloc_Form
),
8895 Pool_Actual
=> Pool_Actual
);
8897 -- Otherwise, if enclosing function has a constrained result subtype,
8898 -- then caller allocation will be used.
8901 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8902 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8905 if Needs_BIP_Finalization_Master
(Enclosing_Func
) then
8908 (Build_In_Place_Formal
8909 (Enclosing_Func
, BIP_Finalization_Master
), Loc
);
8912 -- Retrieve the BIPacc formal from the enclosing function and convert
8913 -- it to the access type of the callee's BIP_Object_Access formal.
8916 Make_Unchecked_Type_Conversion
(Loc
,
8920 (Build_In_Place_Formal
(Function_Id
, BIP_Object_Access
)),
8924 (Build_In_Place_Formal
(Enclosing_Func
, BIP_Object_Access
),
8927 -- In the constrained case, add an implicit actual to the function call
8928 -- that provides access to the declared object. An unchecked conversion
8929 -- to the (specific) result type of the function is inserted to handle
8930 -- the case where the object is declared with a class-wide type.
8932 elsif Is_Constrained
(Underlying_Type
(Result_Subt
)) then
8934 Make_Unchecked_Type_Conversion
(Loc
,
8935 Subtype_Mark
=> New_Reference_To
(Result_Subt
, Loc
),
8936 Expression
=> New_Reference_To
(Obj_Def_Id
, Loc
));
8938 -- When the function has a controlling result, an allocation-form
8939 -- parameter must be passed indicating that the caller is allocating
8940 -- the result object. This is needed because such a function can be
8941 -- called as a dispatching operation and must be treated similarly
8942 -- to functions with unconstrained result subtypes.
8944 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8945 (Func_Call
, Function_Id
, Alloc_Form
=> Caller_Allocation
);
8947 -- In other unconstrained cases, pass an indication to do the allocation
8948 -- on the secondary stack and set Caller_Object to Empty so that a null
8949 -- value will be passed for the caller's object address. A transient
8950 -- scope is established to ensure eventual cleanup of the result.
8953 Add_Unconstrained_Actuals_To_Build_In_Place_Call
8954 (Func_Call
, Function_Id
, Alloc_Form
=> Secondary_Stack
);
8955 Caller_Object
:= Empty
;
8957 Establish_Transient_Scope
(Object_Decl
, Sec_Stack
=> True);
8960 -- Pass along any finalization master actual, which is needed in the
8961 -- case where the called function initializes a return object of an
8962 -- enclosing build-in-place function.
8964 Add_Finalization_Master_Actual_To_Build_In_Place_Call
8965 (Func_Call
=> Func_Call
,
8966 Func_Id
=> Function_Id
,
8967 Master_Exp
=> Fmaster_Actual
);
8969 if Nkind
(Parent
(Object_Decl
)) = N_Extended_Return_Statement
8970 and then Has_Task
(Result_Subt
)
8972 -- Here we're passing along the master that was passed in to this
8975 Add_Task_Actuals_To_Build_In_Place_Call
8976 (Func_Call
, Function_Id
,
8978 New_Reference_To
(Build_In_Place_Formal
8979 (Enclosing_Func
, BIP_Task_Master
), Loc
));
8982 Add_Task_Actuals_To_Build_In_Place_Call
8983 (Func_Call
, Function_Id
, Make_Identifier
(Loc
, Name_uMaster
));
8986 Add_Access_Actual_To_Build_In_Place_Call
8987 (Func_Call
, Function_Id
, Caller_Object
, Is_Access
=> Pass_Caller_Acc
);
8989 -- Create an access type designating the function's result subtype. We
8990 -- use the type of the original expression because it may be a call to
8991 -- an inherited operation, which the expansion has replaced with the
8992 -- parent operation that yields the parent type.
8994 Ref_Type
:= Make_Temporary
(Loc
, 'A');
8997 Make_Full_Type_Declaration
(Loc
,
8998 Defining_Identifier
=> Ref_Type
,
9000 Make_Access_To_Object_Definition
(Loc
,
9001 All_Present
=> True,
9002 Subtype_Indication
=>
9003 New_Reference_To
(Etype
(Function_Call
), Loc
)));
9005 -- The access type and its accompanying object must be inserted after
9006 -- the object declaration in the constrained case, so that the function
9007 -- call can be passed access to the object. In the unconstrained case,
9008 -- or if the object declaration is for a return object, the access type
9009 -- and object must be inserted before the object, since the object
9010 -- declaration is rewritten to be a renaming of a dereference of the
9013 if Is_Constrained
(Underlying_Type
(Result_Subt
))
9014 and then not Is_Return_Object
(Defining_Identifier
(Object_Decl
))
9016 Insert_After_And_Analyze
(Object_Decl
, Ptr_Typ_Decl
);
9018 Insert_Action
(Object_Decl
, Ptr_Typ_Decl
);
9021 -- Finally, create an access object initialized to a reference to the
9022 -- function call. We know this access value cannot be null, so mark the
9023 -- entity accordingly to suppress the access check.
9025 New_Expr
:= Make_Reference
(Loc
, Relocate_Node
(Func_Call
));
9027 Def_Id
:= Make_Temporary
(Loc
, 'R', New_Expr
);
9028 Set_Etype
(Def_Id
, Ref_Type
);
9029 Set_Is_Known_Non_Null
(Def_Id
);
9031 Insert_After_And_Analyze
(Ptr_Typ_Decl
,
9032 Make_Object_Declaration
(Loc
,
9033 Defining_Identifier
=> Def_Id
,
9034 Object_Definition
=> New_Reference_To
(Ref_Type
, Loc
),
9035 Expression
=> New_Expr
));
9037 -- If the result subtype of the called function is constrained and
9038 -- is not itself the return expression of an enclosing BIP function,
9039 -- then mark the object as having no initialization.
9041 if Is_Constrained
(Underlying_Type
(Result_Subt
))
9042 and then not Is_Return_Object
(Defining_Identifier
(Object_Decl
))
9044 Set_Expression
(Object_Decl
, Empty
);
9045 Set_No_Initialization
(Object_Decl
);
9047 -- In case of an unconstrained result subtype, or if the call is the
9048 -- return expression of an enclosing BIP function, rewrite the object
9049 -- declaration as an object renaming where the renamed object is a
9050 -- dereference of <function_Call>'reference:
9052 -- Obj : Subt renames <function_call>'Ref.all;
9056 Make_Explicit_Dereference
(Loc
,
9057 Prefix
=> New_Reference_To
(Def_Id
, Loc
));
9059 Loc
:= Sloc
(Object_Decl
);
9060 Rewrite
(Object_Decl
,
9061 Make_Object_Renaming_Declaration
(Loc
,
9062 Defining_Identifier
=> Make_Temporary
(Loc
, 'D'),
9063 Access_Definition
=> Empty
,
9064 Subtype_Mark
=> New_Occurrence_Of
(Result_Subt
, Loc
),
9065 Name
=> Call_Deref
));
9067 Set_Renamed_Object
(Defining_Identifier
(Object_Decl
), Call_Deref
);
9069 Analyze
(Object_Decl
);
9071 -- Replace the internal identifier of the renaming declaration's
9072 -- entity with identifier of the original object entity. We also have
9073 -- to exchange the entities containing their defining identifiers to
9074 -- ensure the correct replacement of the object declaration by the
9075 -- object renaming declaration to avoid homograph conflicts (since
9076 -- the object declaration's defining identifier was already entered
9077 -- in current scope). The Next_Entity links of the two entities also
9078 -- have to be swapped since the entities are part of the return
9079 -- scope's entity list and the list structure would otherwise be
9080 -- corrupted. Finally, the homonym chain must be preserved as well.
9083 Renaming_Def_Id
: constant Entity_Id
:=
9084 Defining_Identifier
(Object_Decl
);
9085 Next_Entity_Temp
: constant Entity_Id
:=
9086 Next_Entity
(Renaming_Def_Id
);
9088 Set_Chars
(Renaming_Def_Id
, Chars
(Obj_Def_Id
));
9090 -- Swap next entity links in preparation for exchanging entities
9092 Set_Next_Entity
(Renaming_Def_Id
, Next_Entity
(Obj_Def_Id
));
9093 Set_Next_Entity
(Obj_Def_Id
, Next_Entity_Temp
);
9094 Set_Homonym
(Renaming_Def_Id
, Homonym
(Obj_Def_Id
));
9096 Exchange_Entities
(Renaming_Def_Id
, Obj_Def_Id
);
9098 -- Preserve source indication of original declaration, so that
9099 -- xref information is properly generated for the right entity.
9101 Preserve_Comes_From_Source
9102 (Object_Decl
, Original_Node
(Object_Decl
));
9104 Preserve_Comes_From_Source
9105 (Obj_Def_Id
, Original_Node
(Object_Decl
));
9107 Set_Comes_From_Source
(Renaming_Def_Id
, False);
9111 -- If the object entity has a class-wide Etype, then we need to change
9112 -- it to the result subtype of the function call, because otherwise the
9113 -- object will be class-wide without an explicit initialization and
9114 -- won't be allocated properly by the back end. It seems unclean to make
9115 -- such a revision to the type at this point, and we should try to
9116 -- improve this treatment when build-in-place functions with class-wide
9117 -- results are implemented. ???
9119 if Is_Class_Wide_Type
(Etype
(Defining_Identifier
(Object_Decl
))) then
9120 Set_Etype
(Defining_Identifier
(Object_Decl
), Result_Subt
);
9122 end Make_Build_In_Place_Call_In_Object_Declaration
;
9124 --------------------------------------------
9125 -- Make_CPP_Constructor_Call_In_Allocator --
9126 --------------------------------------------
9128 procedure Make_CPP_Constructor_Call_In_Allocator
9129 (Allocator
: Node_Id
;
9130 Function_Call
: Node_Id
)
9132 Loc
: constant Source_Ptr
:= Sloc
(Function_Call
);
9133 Acc_Type
: constant Entity_Id
:= Etype
(Allocator
);
9134 Function_Id
: constant Entity_Id
:= Entity
(Name
(Function_Call
));
9135 Result_Subt
: constant Entity_Id
:= Available_View
(Etype
(Function_Id
));
9137 New_Allocator
: Node_Id
;
9138 Return_Obj_Access
: Entity_Id
;
9142 pragma Assert
(Nkind
(Allocator
) = N_Allocator
9143 and then Nkind
(Function_Call
) = N_Function_Call
);
9144 pragma Assert
(Convention
(Function_Id
) = Convention_CPP
9145 and then Is_Constructor
(Function_Id
));
9146 pragma Assert
(Is_Constrained
(Underlying_Type
(Result_Subt
)));
9148 -- Replace the initialized allocator of form "new T'(Func (...))" with
9149 -- an uninitialized allocator of form "new T", where T is the result
9150 -- subtype of the called function. The call to the function is handled
9151 -- separately further below.
9154 Make_Allocator
(Loc
,
9155 Expression
=> New_Reference_To
(Result_Subt
, Loc
));
9156 Set_No_Initialization
(New_Allocator
);
9158 -- Copy attributes to new allocator. Note that the new allocator
9159 -- logically comes from source if the original one did, so copy the
9160 -- relevant flag. This ensures proper treatment of the restriction
9161 -- No_Implicit_Heap_Allocations in this case.
9163 Set_Storage_Pool
(New_Allocator
, Storage_Pool
(Allocator
));
9164 Set_Procedure_To_Call
(New_Allocator
, Procedure_To_Call
(Allocator
));
9165 Set_Comes_From_Source
(New_Allocator
, Comes_From_Source
(Allocator
));
9167 Rewrite
(Allocator
, New_Allocator
);
9169 -- Create a new access object and initialize it to the result of the
9170 -- new uninitialized allocator. Note: we do not use Allocator as the
9171 -- Related_Node of Return_Obj_Access in call to Make_Temporary below
9172 -- as this would create a sort of infinite "recursion".
9174 Return_Obj_Access
:= Make_Temporary
(Loc
, 'R');
9175 Set_Etype
(Return_Obj_Access
, Acc_Type
);
9178 -- Rnnn : constant ptr_T := new (T);
9179 -- Init (Rnn.all,...);
9182 Make_Object_Declaration
(Loc
,
9183 Defining_Identifier
=> Return_Obj_Access
,
9184 Constant_Present
=> True,
9185 Object_Definition
=> New_Reference_To
(Acc_Type
, Loc
),
9186 Expression
=> Relocate_Node
(Allocator
));
9187 Insert_Action
(Allocator
, Tmp_Obj
);
9189 Insert_List_After_And_Analyze
(Tmp_Obj
,
9190 Build_Initialization_Call
(Loc
,
9192 Make_Explicit_Dereference
(Loc
,
9193 Prefix
=> New_Reference_To
(Return_Obj_Access
, Loc
)),
9194 Typ
=> Etype
(Function_Id
),
9195 Constructor_Ref
=> Function_Call
));
9197 -- Finally, replace the allocator node with a reference to the result of
9198 -- the function call itself (which will effectively be an access to the
9199 -- object created by the allocator).
9201 Rewrite
(Allocator
, New_Reference_To
(Return_Obj_Access
, Loc
));
9203 -- Ada 2005 (AI-251): If the type of the allocator is an interface then
9204 -- generate an implicit conversion to force displacement of the "this"
9207 if Is_Interface
(Designated_Type
(Acc_Type
)) then
9208 Rewrite
(Allocator
, Convert_To
(Acc_Type
, Relocate_Node
(Allocator
)));
9211 Analyze_And_Resolve
(Allocator
, Acc_Type
);
9212 end Make_CPP_Constructor_Call_In_Allocator
;
9214 -----------------------------------
9215 -- Needs_BIP_Finalization_Master --
9216 -----------------------------------
9218 function Needs_BIP_Finalization_Master
9219 (Func_Id
: Entity_Id
) return Boolean
9221 pragma Assert
(Is_Build_In_Place_Function
(Func_Id
));
9222 Func_Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
9225 not Restriction_Active
(No_Finalization
)
9226 and then Needs_Finalization
(Func_Typ
);
9227 end Needs_BIP_Finalization_Master
;
9229 --------------------------
9230 -- Needs_BIP_Alloc_Form --
9231 --------------------------
9233 function Needs_BIP_Alloc_Form
(Func_Id
: Entity_Id
) return Boolean is
9234 pragma Assert
(Is_Build_In_Place_Function
(Func_Id
));
9235 Func_Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
9237 return not Is_Constrained
(Func_Typ
) or else Is_Tagged_Type
(Func_Typ
);
9238 end Needs_BIP_Alloc_Form
;
9240 --------------------------------------
9241 -- Needs_Result_Accessibility_Level --
9242 --------------------------------------
9244 function Needs_Result_Accessibility_Level
9245 (Func_Id
: Entity_Id
) return Boolean
9247 Func_Typ
: constant Entity_Id
:= Underlying_Type
(Etype
(Func_Id
));
9249 function Has_Unconstrained_Access_Discriminant_Component
9250 (Comp_Typ
: Entity_Id
) return Boolean;
9251 -- Returns True if any component of the type has an unconstrained access
9254 -----------------------------------------------------
9255 -- Has_Unconstrained_Access_Discriminant_Component --
9256 -----------------------------------------------------
9258 function Has_Unconstrained_Access_Discriminant_Component
9259 (Comp_Typ
: Entity_Id
) return Boolean
9262 if not Is_Limited_Type
(Comp_Typ
) then
9265 -- Only limited types can have access discriminants with
9268 elsif Has_Unconstrained_Access_Discriminants
(Comp_Typ
) then
9271 elsif Is_Array_Type
(Comp_Typ
) then
9272 return Has_Unconstrained_Access_Discriminant_Component
9273 (Underlying_Type
(Component_Type
(Comp_Typ
)));
9275 elsif Is_Record_Type
(Comp_Typ
) then
9280 Comp
:= First_Component
(Comp_Typ
);
9281 while Present
(Comp
) loop
9282 if Has_Unconstrained_Access_Discriminant_Component
9283 (Underlying_Type
(Etype
(Comp
)))
9288 Next_Component
(Comp
);
9294 end Has_Unconstrained_Access_Discriminant_Component
;
9296 Feature_Disabled
: constant Boolean := True;
9299 -- Start of processing for Needs_Result_Accessibility_Level
9302 -- False if completion unavailable (how does this happen???)
9304 if not Present
(Func_Typ
) then
9307 elsif Feature_Disabled
then
9310 -- False if not a function, also handle enum-lit renames case
9312 elsif Func_Typ
= Standard_Void_Type
9313 or else Is_Scalar_Type
(Func_Typ
)
9317 -- Handle a corner case, a cross-dialect subp renaming. For example,
9318 -- an Ada 2012 renaming of an Ada 2005 subprogram. This can occur when
9319 -- an Ada 2005 (or earlier) unit references predefined run-time units.
9321 elsif Present
(Alias
(Func_Id
)) then
9323 -- Unimplemented: a cross-dialect subp renaming which does not set
9324 -- the Alias attribute (e.g., a rename of a dereference of an access
9325 -- to subprogram value). ???
9327 return Present
(Extra_Accessibility_Of_Result
(Alias
(Func_Id
)));
9329 -- Remaining cases require Ada 2012 mode
9331 elsif Ada_Version
< Ada_2012
then
9334 elsif Ekind
(Func_Typ
) = E_Anonymous_Access_Type
9335 or else Is_Tagged_Type
(Func_Typ
)
9337 -- In the case of, say, a null tagged record result type, the need
9338 -- for this extra parameter might not be obvious. This function
9339 -- returns True for all tagged types for compatibility reasons.
9340 -- A function with, say, a tagged null controlling result type might
9341 -- be overridden by a primitive of an extension having an access
9342 -- discriminant and the overrider and overridden must have compatible
9343 -- calling conventions (including implicitly declared parameters).
9344 -- Similarly, values of one access-to-subprogram type might designate
9345 -- both a primitive subprogram of a given type and a function
9346 -- which is, for example, not a primitive subprogram of any type.
9347 -- Again, this requires calling convention compatibility.
9348 -- It might be possible to solve these issues by introducing
9349 -- wrappers, but that is not the approach that was chosen.
9353 elsif Has_Unconstrained_Access_Discriminants
(Func_Typ
) then
9356 elsif Has_Unconstrained_Access_Discriminant_Component
(Func_Typ
) then
9359 -- False for all other cases
9364 end Needs_Result_Accessibility_Level
;
9366 ------------------------
9367 -- List_Inlining_Info --
9368 ------------------------
9370 procedure List_Inlining_Info
is
9376 if not Debug_Flag_Dot_J
then
9380 -- Generate listing of calls inlined by the frontend
9382 if Present
(Inlined_Calls
) then
9384 Elmt
:= First_Elmt
(Inlined_Calls
);
9385 while Present
(Elmt
) loop
9388 if In_Extended_Main_Code_Unit
(Nod
) then
9392 Write_Str
("Listing of frontend inlined calls");
9399 Write_Location
(Sloc
(Nod
));
9408 -- Generate listing of calls passed to the backend
9410 if Present
(Backend_Calls
) then
9413 Elmt
:= First_Elmt
(Backend_Calls
);
9414 while Present
(Elmt
) loop
9417 if In_Extended_Main_Code_Unit
(Nod
) then
9421 Write_Str
("Listing of inlined calls passed to the backend");
9428 Write_Location
(Sloc
(Nod
));
9435 end List_Inlining_Info
;