1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2015, 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 Aspects
; use Aspects
;
27 with Atree
; use Atree
;
28 with Debug
; use Debug
;
29 with Einfo
; use Einfo
;
30 with Elists
; use Elists
;
31 with Errout
; use Errout
;
32 with Expander
; use Expander
;
33 with Exp_Ch6
; use Exp_Ch6
;
34 with Exp_Ch7
; use Exp_Ch7
;
35 with Exp_Tss
; use Exp_Tss
;
36 with Exp_Util
; use Exp_Util
;
37 with Fname
; use Fname
;
38 with Fname
.UF
; use Fname
.UF
;
40 with Namet
; use Namet
;
41 with Nmake
; use Nmake
;
42 with Nlists
; use Nlists
;
43 with Output
; use Output
;
44 with Sem_Aux
; use Sem_Aux
;
45 with Sem_Ch8
; use Sem_Ch8
;
46 with Sem_Ch10
; use Sem_Ch10
;
47 with Sem_Ch12
; use Sem_Ch12
;
48 with Sem_Prag
; use Sem_Prag
;
49 with Sem_Util
; use Sem_Util
;
50 with Sinfo
; use Sinfo
;
51 with Sinput
; use Sinput
;
52 with Snames
; use Snames
;
53 with Stand
; use Stand
;
54 with Uname
; use Uname
;
55 with Tbuild
; use Tbuild
;
57 package body Inline
is
59 Check_Inlining_Restrictions
: constant Boolean := True;
60 -- In the following cases the frontend rejects inlining because they
61 -- are not handled well by the backend. This variable facilitates
62 -- disabling these restrictions to evaluate future versions of the
63 -- GCC backend in which some of the restrictions may be supported.
65 -- - subprograms that have:
66 -- - nested subprograms
68 -- - package declarations
69 -- - task or protected object declarations
70 -- - some of the following statements:
72 -- - asynchronous-select
73 -- - conditional-entry-call
79 Inlined_Calls
: Elist_Id
;
80 -- List of frontend inlined calls
82 Backend_Calls
: Elist_Id
;
83 -- List of inline calls passed to the backend
85 Backend_Inlined_Subps
: Elist_Id
;
86 -- List of subprograms inlined by the backend
88 Backend_Not_Inlined_Subps
: Elist_Id
;
89 -- List of subprograms that cannot be inlined by the backend
95 -- Inlined functions are actually placed in line by the backend if the
96 -- corresponding bodies are available (i.e. compiled). Whenever we find
97 -- a call to an inlined subprogram, we add the name of the enclosing
98 -- compilation unit to a worklist. After all compilation, and after
99 -- expansion of generic bodies, we traverse the list of pending bodies
100 -- and compile them as well.
102 package Inlined_Bodies
is new Table
.Table
(
103 Table_Component_Type
=> Entity_Id
,
104 Table_Index_Type
=> Int
,
105 Table_Low_Bound
=> 0,
106 Table_Initial
=> Alloc
.Inlined_Bodies_Initial
,
107 Table_Increment
=> Alloc
.Inlined_Bodies_Increment
,
108 Table_Name
=> "Inlined_Bodies");
110 -----------------------
111 -- Inline Processing --
112 -----------------------
114 -- For each call to an inlined subprogram, we make entries in a table
115 -- that stores caller and callee, and indicates the call direction from
116 -- one to the other. We also record the compilation unit that contains
117 -- the callee. After analyzing the bodies of all such compilation units,
118 -- we compute the transitive closure of inlined subprograms called from
119 -- the main compilation unit and make it available to the code generator
120 -- in no particular order, thus allowing cycles in the call graph.
122 Last_Inlined
: Entity_Id
:= Empty
;
124 -- For each entry in the table we keep a list of successors in topological
125 -- order, i.e. callers of the current subprogram.
127 type Subp_Index
is new Nat
;
128 No_Subp
: constant Subp_Index
:= 0;
130 -- The subprogram entities are hashed into the Inlined table
132 Num_Hash_Headers
: constant := 512;
134 Hash_Headers
: array (Subp_Index
range 0 .. Num_Hash_Headers
- 1)
137 type Succ_Index
is new Nat
;
138 No_Succ
: constant Succ_Index
:= 0;
140 type Succ_Info
is record
145 -- The following table stores list elements for the successor lists. These
146 -- lists cannot be chained directly through entries in the Inlined table,
147 -- because a given subprogram can appear in several such lists.
149 package Successors
is new Table
.Table
(
150 Table_Component_Type
=> Succ_Info
,
151 Table_Index_Type
=> Succ_Index
,
152 Table_Low_Bound
=> 1,
153 Table_Initial
=> Alloc
.Successors_Initial
,
154 Table_Increment
=> Alloc
.Successors_Increment
,
155 Table_Name
=> "Successors");
157 type Subp_Info
is record
158 Name
: Entity_Id
:= Empty
;
159 Next
: Subp_Index
:= No_Subp
;
160 First_Succ
: Succ_Index
:= No_Succ
;
161 Main_Call
: Boolean := False;
162 Processed
: Boolean := False;
165 package Inlined
is new Table
.Table
(
166 Table_Component_Type
=> Subp_Info
,
167 Table_Index_Type
=> Subp_Index
,
168 Table_Low_Bound
=> 1,
169 Table_Initial
=> Alloc
.Inlined_Initial
,
170 Table_Increment
=> Alloc
.Inlined_Increment
,
171 Table_Name
=> "Inlined");
173 -----------------------
174 -- Local Subprograms --
175 -----------------------
177 procedure Add_Call
(Called
: Entity_Id
; Caller
: Entity_Id
:= Empty
);
178 -- Make two entries in Inlined table, for an inlined subprogram being
179 -- called, and for the inlined subprogram that contains the call. If
180 -- the call is in the main compilation unit, Caller is Empty.
182 procedure Add_Inlined_Subprogram
(E
: Entity_Id
);
183 -- Add subprogram E to the list of inlined subprogram for the unit
185 function Add_Subp
(E
: Entity_Id
) return Subp_Index
;
186 -- Make entry in Inlined table for subprogram E, or return table index
187 -- that already holds E.
189 function Get_Code_Unit_Entity
(E
: Entity_Id
) return Entity_Id
;
190 pragma Inline
(Get_Code_Unit_Entity
);
191 -- Return the entity node for the unit containing E. Always return the spec
194 function Has_Initialized_Type
(E
: Entity_Id
) return Boolean;
195 -- If a candidate for inlining contains type declarations for types with
196 -- nontrivial initialization procedures, they are not worth inlining.
198 function Has_Single_Return
(N
: Node_Id
) return Boolean;
199 -- In general we cannot inline functions that return unconstrained type.
200 -- However, we can handle such functions if all return statements return a
201 -- local variable that is the only declaration in the body of the function.
202 -- In that case the call can be replaced by that local variable as is done
203 -- for other inlined calls.
205 function In_Main_Unit_Or_Subunit
(E
: Entity_Id
) return Boolean;
206 -- Return True if E is in the main unit or its spec or in a subunit
208 function Is_Nested
(E
: Entity_Id
) return Boolean;
209 -- If the function is nested inside some other function, it will always
210 -- be compiled if that function is, so don't add it to the inline list.
211 -- We cannot compile a nested function outside the scope of the containing
212 -- function anyway. This is also the case if the function is defined in a
213 -- task body or within an entry (for example, an initialization procedure).
215 procedure Remove_Aspects_And_Pragmas
(Body_Decl
: Node_Id
);
216 -- Remove all aspects and/or pragmas that have no meaning in inlined body
217 -- Body_Decl. The analysis of these items is performed on the non-inlined
218 -- body. The items currently removed are:
231 ------------------------------
232 -- Deferred Cleanup Actions --
233 ------------------------------
235 -- The cleanup actions for scopes that contain instantiations is delayed
236 -- until after expansion of those instantiations, because they may contain
237 -- finalizable objects or tasks that affect the cleanup code. A scope
238 -- that contains instantiations only needs to be finalized once, even
239 -- if it contains more than one instance. We keep a list of scopes
240 -- that must still be finalized, and call cleanup_actions after all
241 -- the instantiations have been completed.
245 procedure Add_Scope_To_Clean
(Inst
: Entity_Id
);
246 -- Build set of scopes on which cleanup actions must be performed
248 procedure Cleanup_Scopes
;
249 -- Complete cleanup actions on scopes that need it
255 procedure Add_Call
(Called
: Entity_Id
; Caller
: Entity_Id
:= Empty
) is
256 P1
: constant Subp_Index
:= Add_Subp
(Called
);
261 if Present
(Caller
) then
262 P2
:= Add_Subp
(Caller
);
264 -- Add P1 to the list of successors of P2, if not already there.
265 -- Note that P2 may contain more than one call to P1, and only
266 -- one needs to be recorded.
268 J
:= Inlined
.Table
(P2
).First_Succ
;
269 while J
/= No_Succ
loop
270 if Successors
.Table
(J
).Subp
= P1
then
274 J
:= Successors
.Table
(J
).Next
;
277 -- On exit, make a successor entry for P1
279 Successors
.Increment_Last
;
280 Successors
.Table
(Successors
.Last
).Subp
:= P1
;
281 Successors
.Table
(Successors
.Last
).Next
:=
282 Inlined
.Table
(P2
).First_Succ
;
283 Inlined
.Table
(P2
).First_Succ
:= Successors
.Last
;
285 Inlined
.Table
(P1
).Main_Call
:= True;
289 ----------------------
290 -- Add_Inlined_Body --
291 ----------------------
293 procedure Add_Inlined_Body
(E
: Entity_Id
; N
: Node_Id
) is
295 type Inline_Level_Type
is (Dont_Inline
, Inline_Call
, Inline_Package
);
296 -- Level of inlining for the call: Dont_Inline means no inlining,
297 -- Inline_Call means that only the call is considered for inlining,
298 -- Inline_Package means that the call is considered for inlining and
299 -- its package compiled and scanned for more inlining opportunities.
301 function Must_Inline
return Inline_Level_Type
;
302 -- Inlining is only done if the call statement N is in the main unit,
303 -- or within the body of another inlined subprogram.
309 function Must_Inline
return Inline_Level_Type
is
314 -- Check if call is in main unit
316 Scop
:= Current_Scope
;
318 -- Do not try to inline if scope is standard. This could happen, for
319 -- example, for a call to Add_Global_Declaration, and it causes
320 -- trouble to try to inline at this level.
322 if Scop
= Standard_Standard
then
326 -- Otherwise lookup scope stack to outer scope
328 while Scope
(Scop
) /= Standard_Standard
329 and then not Is_Child_Unit
(Scop
)
331 Scop
:= Scope
(Scop
);
334 Comp
:= Parent
(Scop
);
335 while Nkind
(Comp
) /= N_Compilation_Unit
loop
336 Comp
:= Parent
(Comp
);
339 -- If the call is in the main unit, inline the call and compile the
340 -- package of the subprogram to find more calls to be inlined.
342 if Comp
= Cunit
(Main_Unit
)
343 or else Comp
= Library_Unit
(Cunit
(Main_Unit
))
346 return Inline_Package
;
349 -- The call is not in the main unit. See if it is in some subprogram
350 -- that can be inlined outside its unit. If so, inline the call and,
351 -- if the inlining level is set to 1, stop there; otherwise also
352 -- compile the package as above.
354 Scop
:= Current_Scope
;
355 while Scope
(Scop
) /= Standard_Standard
356 and then not Is_Child_Unit
(Scop
)
358 if Is_Overloadable
(Scop
)
359 and then Is_Inlined
(Scop
)
360 and then not Is_Nested
(Scop
)
364 if Inline_Level
= 1 then
367 return Inline_Package
;
371 Scop
:= Scope
(Scop
);
377 Level
: Inline_Level_Type
;
379 -- Start of processing for Add_Inlined_Body
382 Append_New_Elmt
(N
, To
=> Backend_Calls
);
384 -- Skip subprograms that cannot be inlined outside their unit
386 if Is_Abstract_Subprogram
(E
)
387 or else Convention
(E
) = Convention_Protected
388 or else Is_Nested
(E
)
393 -- Find unit containing E, and add to list of inlined bodies if needed.
394 -- If the body is already present, no need to load any other unit. This
395 -- is the case for an initialization procedure, which appears in the
396 -- package declaration that contains the type. It is also the case if
397 -- the body has already been analyzed. Finally, if the unit enclosing
398 -- E is an instance, the instance body will be analyzed in any case,
399 -- and there is no need to add the enclosing unit (whose body might not
402 -- Library-level functions must be handled specially, because there is
403 -- no enclosing package to retrieve. In this case, it is the body of
404 -- the function that will have to be loaded.
406 Level
:= Must_Inline
;
408 if Level
/= Dont_Inline
then
410 Pack
: constant Entity_Id
:= Get_Code_Unit_Entity
(E
);
413 -- Ensure that Analyze_Inlined_Bodies will be invoked after
414 -- completing the analysis of the current unit.
416 Inline_Processing_Required
:= True;
420 -- Library-level inlined function. Add function itself to
421 -- list of needed units.
424 Inlined_Bodies
.Increment_Last
;
425 Inlined_Bodies
.Table
(Inlined_Bodies
.Last
) := E
;
427 elsif Ekind
(Pack
) = E_Package
then
430 if Is_Generic_Instance
(Pack
) then
433 -- Do not inline the package if the subprogram is an init proc
434 -- or other internally generated subprogram, because in that
435 -- case the subprogram body appears in the same unit that
436 -- declares the type, and that body is visible to the back end.
437 -- Do not inline it either if it is in the main unit.
439 elsif Level
= Inline_Package
440 and then not Is_Inlined
(Pack
)
441 and then not Is_Internal
(E
)
442 and then not In_Main_Unit_Or_Subunit
(Pack
)
444 Set_Is_Inlined
(Pack
);
445 Inlined_Bodies
.Increment_Last
;
446 Inlined_Bodies
.Table
(Inlined_Bodies
.Last
) := Pack
;
448 -- Extend the -gnatn2 processing to -gnatn1 for Inline_Always
449 -- calls if the back-end takes care of inlining the call.
451 elsif Level
= Inline_Call
452 and then Has_Pragma_Inline_Always
(E
)
453 and then Back_End_Inlining
455 Set_Is_Inlined
(Pack
);
456 Inlined_Bodies
.Increment_Last
;
457 Inlined_Bodies
.Table
(Inlined_Bodies
.Last
) := Pack
;
461 -- If the call was generated by the compiler and is to a function
462 -- in a run-time unit, we need to suppress debugging information
463 -- for it, so that the code that is eventually inlined will not
464 -- affect debugging of the program. We do not do it if the call
465 -- comes from source because, even if the call is inlined, the
466 -- user may expect it to be present in the debugging information.
468 if not Comes_From_Source
(N
)
469 and then In_Extended_Main_Source_Unit
(N
)
471 Is_Predefined_File_Name
(Unit_File_Name
(Get_Source_Unit
(E
)))
473 Set_Needs_Debug_Info
(E
, False);
477 end Add_Inlined_Body
;
479 ----------------------------
480 -- Add_Inlined_Subprogram --
481 ----------------------------
483 procedure Add_Inlined_Subprogram
(E
: Entity_Id
) is
484 Decl
: constant Node_Id
:= Parent
(Declaration_Node
(E
));
485 Pack
: constant Entity_Id
:= Get_Code_Unit_Entity
(E
);
487 procedure Register_Backend_Inlined_Subprogram
(Subp
: Entity_Id
);
488 -- Append Subp to the list of subprograms inlined by the backend
490 procedure Register_Backend_Not_Inlined_Subprogram
(Subp
: Entity_Id
);
491 -- Append Subp to the list of subprograms that cannot be inlined by
494 -----------------------------------------
495 -- Register_Backend_Inlined_Subprogram --
496 -----------------------------------------
498 procedure Register_Backend_Inlined_Subprogram
(Subp
: Entity_Id
) is
500 Append_New_Elmt
(Subp
, To
=> Backend_Inlined_Subps
);
501 end Register_Backend_Inlined_Subprogram
;
503 ---------------------------------------------
504 -- Register_Backend_Not_Inlined_Subprogram --
505 ---------------------------------------------
507 procedure Register_Backend_Not_Inlined_Subprogram
(Subp
: Entity_Id
) is
509 Append_New_Elmt
(Subp
, To
=> Backend_Not_Inlined_Subps
);
510 end Register_Backend_Not_Inlined_Subprogram
;
512 -- Start of processing for Add_Inlined_Subprogram
515 -- If the subprogram is to be inlined, and if its unit is known to be
516 -- inlined or is an instance whose body will be analyzed anyway or the
517 -- subprogram was generated as a body by the compiler (for example an
518 -- initialization procedure) or its declaration was provided along with
519 -- the body (for example an expression function), and if it is declared
520 -- at the library level not in the main unit, and if it can be inlined
521 -- by the back-end, then insert it in the list of inlined subprograms.
524 and then (Is_Inlined
(Pack
)
525 or else Is_Generic_Instance
(Pack
)
526 or else Nkind
(Decl
) = N_Subprogram_Body
527 or else Present
(Corresponding_Body
(Decl
)))
528 and then not In_Main_Unit_Or_Subunit
(E
)
529 and then not Is_Nested
(E
)
530 and then not Has_Initialized_Type
(E
)
532 Register_Backend_Inlined_Subprogram
(E
);
534 if No
(Last_Inlined
) then
535 Set_First_Inlined_Subprogram
(Cunit
(Main_Unit
), E
);
537 Set_Next_Inlined_Subprogram
(Last_Inlined
, E
);
543 Register_Backend_Not_Inlined_Subprogram
(E
);
545 end Add_Inlined_Subprogram
;
547 ------------------------
548 -- Add_Scope_To_Clean --
549 ------------------------
551 procedure Add_Scope_To_Clean
(Inst
: Entity_Id
) is
552 Scop
: constant Entity_Id
:= Enclosing_Dynamic_Scope
(Inst
);
556 -- If the instance appears in a library-level package declaration,
557 -- all finalization is global, and nothing needs doing here.
559 if Scop
= Standard_Standard
then
563 -- If the instance is within a generic unit, no finalization code
564 -- can be generated. Note that at this point all bodies have been
565 -- analyzed, and the scope stack itself is not present, and the flag
566 -- Inside_A_Generic is not set.
573 while Present
(S
) and then S
/= Standard_Standard
loop
574 if Is_Generic_Unit
(S
) then
582 Elmt
:= First_Elmt
(To_Clean
);
583 while Present
(Elmt
) loop
584 if Node
(Elmt
) = Scop
then
588 Elmt
:= Next_Elmt
(Elmt
);
591 Append_Elmt
(Scop
, To_Clean
);
592 end Add_Scope_To_Clean
;
598 function Add_Subp
(E
: Entity_Id
) return Subp_Index
is
599 Index
: Subp_Index
:= Subp_Index
(E
) mod Num_Hash_Headers
;
603 -- Initialize entry in Inlined table
605 procedure New_Entry
is
607 Inlined
.Increment_Last
;
608 Inlined
.Table
(Inlined
.Last
).Name
:= E
;
609 Inlined
.Table
(Inlined
.Last
).Next
:= No_Subp
;
610 Inlined
.Table
(Inlined
.Last
).First_Succ
:= No_Succ
;
611 Inlined
.Table
(Inlined
.Last
).Main_Call
:= False;
612 Inlined
.Table
(Inlined
.Last
).Processed
:= False;
615 -- Start of processing for Add_Subp
618 if Hash_Headers
(Index
) = No_Subp
then
620 Hash_Headers
(Index
) := Inlined
.Last
;
624 J
:= Hash_Headers
(Index
);
625 while J
/= No_Subp
loop
626 if Inlined
.Table
(J
).Name
= E
then
630 J
:= Inlined
.Table
(J
).Next
;
634 -- On exit, subprogram was not found. Enter in table. Index is
635 -- the current last entry on the hash chain.
638 Inlined
.Table
(Index
).Next
:= Inlined
.Last
;
643 ----------------------------
644 -- Analyze_Inlined_Bodies --
645 ----------------------------
647 procedure Analyze_Inlined_Bodies
is
654 type Pending_Index
is new Nat
;
656 package Pending_Inlined
is new Table
.Table
(
657 Table_Component_Type
=> Subp_Index
,
658 Table_Index_Type
=> Pending_Index
,
659 Table_Low_Bound
=> 1,
660 Table_Initial
=> Alloc
.Inlined_Initial
,
661 Table_Increment
=> Alloc
.Inlined_Increment
,
662 Table_Name
=> "Pending_Inlined");
663 -- The workpile used to compute the transitive closure
665 function Is_Ancestor_Of_Main
667 Nam
: Node_Id
) return Boolean;
668 -- Determine whether the unit whose body is loaded is an ancestor of
669 -- the main unit, and has a with_clause on it. The body is not
670 -- analyzed yet, so the check is purely lexical: the name of the with
671 -- clause is a selected component, and names of ancestors must match.
673 -------------------------
674 -- Is_Ancestor_Of_Main --
675 -------------------------
677 function Is_Ancestor_Of_Main
679 Nam
: Node_Id
) return Boolean
684 if Nkind
(Nam
) /= N_Selected_Component
then
688 if Chars
(Selector_Name
(Nam
)) /=
689 Chars
(Cunit_Entity
(Main_Unit
))
694 Pref
:= Prefix
(Nam
);
695 if Nkind
(Pref
) = N_Identifier
then
697 -- Par is an ancestor of Par.Child.
699 return Chars
(Pref
) = Chars
(U_Name
);
701 elsif Nkind
(Pref
) = N_Selected_Component
702 and then Chars
(Selector_Name
(Pref
)) = Chars
(U_Name
)
704 -- Par.Child is an ancestor of Par.Child.Grand.
706 return True; -- should check that ancestor match
709 -- A is an ancestor of A.B.C if it is an ancestor of A.B
711 return Is_Ancestor_Of_Main
(U_Name
, Pref
);
714 end Is_Ancestor_Of_Main
;
716 -- Start of processing for Analyze_Inlined_Bodies
719 if Serious_Errors_Detected
= 0 then
720 Push_Scope
(Standard_Standard
);
723 while J
<= Inlined_Bodies
.Last
724 and then Serious_Errors_Detected
= 0
726 Pack
:= Inlined_Bodies
.Table
(J
);
728 and then Scope
(Pack
) /= Standard_Standard
729 and then not Is_Child_Unit
(Pack
)
731 Pack
:= Scope
(Pack
);
734 Comp_Unit
:= Parent
(Pack
);
735 while Present
(Comp_Unit
)
736 and then Nkind
(Comp_Unit
) /= N_Compilation_Unit
738 Comp_Unit
:= Parent
(Comp_Unit
);
741 -- Load the body, unless it is the main unit, or is an instance
742 -- whose body has already been analyzed.
744 if Present
(Comp_Unit
)
745 and then Comp_Unit
/= Cunit
(Main_Unit
)
746 and then Body_Required
(Comp_Unit
)
747 and then (Nkind
(Unit
(Comp_Unit
)) /= N_Package_Declaration
748 or else No
(Corresponding_Body
(Unit
(Comp_Unit
))))
751 Bname
: constant Unit_Name_Type
:=
752 Get_Body_Name
(Get_Unit_Name
(Unit
(Comp_Unit
)));
757 if not Is_Loaded
(Bname
) then
758 Style_Check
:= False;
759 Load_Needed_Body
(Comp_Unit
, OK
, Do_Analyze
=> False);
763 -- Warn that a body was not available for inlining
766 Error_Msg_Unit_1
:= Bname
;
768 ("one or more inlined subprograms accessed in $!??",
771 Get_File_Name
(Bname
, Subunit
=> False);
772 Error_Msg_N
("\but file{ was not found!??", Comp_Unit
);
775 -- If the package to be inlined is an ancestor unit of
776 -- the main unit, and it has a semantic dependence on
777 -- it, the inlining cannot take place to prevent an
778 -- elaboration circularity. The desired body is not
779 -- analyzed yet, to prevent the completion of Taft
780 -- amendment types that would lead to elaboration
781 -- circularities in gigi.
784 U_Id
: constant Entity_Id
:=
785 Defining_Entity
(Unit
(Comp_Unit
));
786 Body_Unit
: constant Node_Id
:=
787 Library_Unit
(Comp_Unit
);
791 Item
:= First
(Context_Items
(Body_Unit
));
792 while Present
(Item
) loop
793 if Nkind
(Item
) = N_With_Clause
795 Is_Ancestor_Of_Main
(U_Id
, Name
(Item
))
797 Set_Is_Inlined
(U_Id
, False);
804 -- If no suspicious with_clauses, analyze the body.
806 if Is_Inlined
(U_Id
) then
807 Semantics
(Body_Unit
);
817 if J
> Inlined_Bodies
.Last
then
819 -- The analysis of required bodies may have produced additional
820 -- generic instantiations. To obtain further inlining, we need
821 -- to perform another round of generic body instantiations.
825 -- Symmetrically, the instantiation of required generic bodies
826 -- may have caused additional bodies to be inlined. To obtain
827 -- further inlining, we keep looping over the inlined bodies.
831 -- The list of inlined subprograms is an overestimate, because it
832 -- includes inlined functions called from functions that are compiled
833 -- as part of an inlined package, but are not themselves called. An
834 -- accurate computation of just those subprograms that are needed
835 -- requires that we perform a transitive closure over the call graph,
836 -- starting from calls in the main compilation unit.
838 for Index
in Inlined
.First
.. Inlined
.Last
loop
839 if not Is_Called
(Inlined
.Table
(Index
).Name
) then
841 -- This means that Add_Inlined_Body added the subprogram to the
842 -- table but wasn't able to handle its code unit. Do nothing.
844 Inlined
.Table
(Index
).Processed
:= True;
846 elsif Inlined
.Table
(Index
).Main_Call
then
847 Pending_Inlined
.Increment_Last
;
848 Pending_Inlined
.Table
(Pending_Inlined
.Last
) := Index
;
849 Inlined
.Table
(Index
).Processed
:= True;
852 Set_Is_Called
(Inlined
.Table
(Index
).Name
, False);
856 -- Iterate over the workpile until it is emptied, propagating the
857 -- Is_Called flag to the successors of the processed subprogram.
859 while Pending_Inlined
.Last
>= Pending_Inlined
.First
loop
860 Subp
:= Pending_Inlined
.Table
(Pending_Inlined
.Last
);
861 Pending_Inlined
.Decrement_Last
;
863 S
:= Inlined
.Table
(Subp
).First_Succ
;
865 while S
/= No_Succ
loop
866 Subp
:= Successors
.Table
(S
).Subp
;
868 if not Inlined
.Table
(Subp
).Processed
then
869 Set_Is_Called
(Inlined
.Table
(Subp
).Name
);
870 Pending_Inlined
.Increment_Last
;
871 Pending_Inlined
.Table
(Pending_Inlined
.Last
) := Subp
;
872 Inlined
.Table
(Subp
).Processed
:= True;
875 S
:= Successors
.Table
(S
).Next
;
879 -- Finally add the called subprograms to the list of inlined
880 -- subprograms for the unit.
882 for Index
in Inlined
.First
.. Inlined
.Last
loop
883 if Is_Called
(Inlined
.Table
(Index
).Name
) then
884 Add_Inlined_Subprogram
(Inlined
.Table
(Index
).Name
);
890 end Analyze_Inlined_Bodies
;
892 --------------------------
893 -- Build_Body_To_Inline --
894 --------------------------
896 procedure Build_Body_To_Inline
(N
: Node_Id
; Spec_Id
: Entity_Id
) is
897 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Spec_Id
);
898 Analysis_Status
: constant Boolean := Full_Analysis
;
899 Original_Body
: Node_Id
;
900 Body_To_Analyze
: Node_Id
;
901 Max_Size
: constant := 10;
903 function Has_Pending_Instantiation
return Boolean;
904 -- If some enclosing body contains instantiations that appear before
905 -- the corresponding generic body, the enclosing body has a freeze node
906 -- so that it can be elaborated after the generic itself. This might
907 -- conflict with subsequent inlinings, so that it is unsafe to try to
908 -- inline in such a case.
910 function Has_Single_Return_In_GNATprove_Mode
return Boolean;
911 -- This function is called only in GNATprove mode, and it returns
912 -- True if the subprogram has no return statement or a single return
913 -- statement as last statement. It returns False for subprogram with
914 -- a single return as last statement inside one or more blocks, as
915 -- inlining would generate gotos in that case as well (although the
916 -- goto is useless in that case).
918 function Uses_Secondary_Stack
(Bod
: Node_Id
) return Boolean;
919 -- If the body of the subprogram includes a call that returns an
920 -- unconstrained type, the secondary stack is involved, and it
921 -- is not worth inlining.
923 -------------------------------
924 -- Has_Pending_Instantiation --
925 -------------------------------
927 function Has_Pending_Instantiation
return Boolean is
932 while Present
(S
) loop
933 if Is_Compilation_Unit
(S
)
934 or else Is_Child_Unit
(S
)
938 elsif Ekind
(S
) = E_Package
939 and then Has_Forward_Instantiation
(S
)
948 end Has_Pending_Instantiation
;
950 -----------------------------------------
951 -- Has_Single_Return_In_GNATprove_Mode --
952 -----------------------------------------
954 function Has_Single_Return_In_GNATprove_Mode
return Boolean is
955 Last_Statement
: Node_Id
:= Empty
;
957 function Check_Return
(N
: Node_Id
) return Traverse_Result
;
958 -- Returns OK on node N if this is not a return statement different
959 -- from the last statement in the subprogram.
965 function Check_Return
(N
: Node_Id
) return Traverse_Result
is
967 if Nkind_In
(N
, N_Simple_Return_Statement
,
968 N_Extended_Return_Statement
)
970 if N
= Last_Statement
then
981 function Check_All_Returns
is new Traverse_Func
(Check_Return
);
983 -- Start of processing for Has_Single_Return_In_GNATprove_Mode
986 -- Retrieve the last statement
988 Last_Statement
:= Last
(Statements
(Handled_Statement_Sequence
(N
)));
990 -- Check that the last statement is the only possible return
991 -- statement in the subprogram.
993 return Check_All_Returns
(N
) = OK
;
994 end Has_Single_Return_In_GNATprove_Mode
;
996 --------------------------
997 -- Uses_Secondary_Stack --
998 --------------------------
1000 function Uses_Secondary_Stack
(Bod
: Node_Id
) return Boolean is
1001 function Check_Call
(N
: Node_Id
) return Traverse_Result
;
1002 -- Look for function calls that return an unconstrained type
1008 function Check_Call
(N
: Node_Id
) return Traverse_Result
is
1010 if Nkind
(N
) = N_Function_Call
1011 and then Is_Entity_Name
(Name
(N
))
1012 and then Is_Composite_Type
(Etype
(Entity
(Name
(N
))))
1013 and then not Is_Constrained
(Etype
(Entity
(Name
(N
))))
1016 ("cannot inline & (call returns unconstrained type)?",
1024 function Check_Calls
is new Traverse_Func
(Check_Call
);
1027 return Check_Calls
(Bod
) = Abandon
;
1028 end Uses_Secondary_Stack
;
1030 -- Start of processing for Build_Body_To_Inline
1033 -- Return immediately if done already
1035 if Nkind
(Decl
) = N_Subprogram_Declaration
1036 and then Present
(Body_To_Inline
(Decl
))
1040 -- Subprograms that have return statements in the middle of the body are
1041 -- inlined with gotos. GNATprove does not currently support gotos, so
1042 -- we prevent such inlining.
1044 elsif GNATprove_Mode
1045 and then not Has_Single_Return_In_GNATprove_Mode
1047 Cannot_Inline
("cannot inline & (multiple returns)?", N
, Spec_Id
);
1050 -- Functions that return unconstrained composite types require
1051 -- secondary stack handling, and cannot currently be inlined, unless
1052 -- all return statements return a local variable that is the first
1053 -- local declaration in the body.
1055 elsif Ekind
(Spec_Id
) = E_Function
1056 and then not Is_Scalar_Type
(Etype
(Spec_Id
))
1057 and then not Is_Access_Type
(Etype
(Spec_Id
))
1058 and then not Is_Constrained
(Etype
(Spec_Id
))
1060 if not Has_Single_Return
(N
) then
1062 ("cannot inline & (unconstrained return type)?", N
, Spec_Id
);
1066 -- Ditto for functions that return controlled types, where controlled
1067 -- actions interfere in complex ways with inlining.
1069 elsif Ekind
(Spec_Id
) = E_Function
1070 and then Needs_Finalization
(Etype
(Spec_Id
))
1073 ("cannot inline & (controlled return type)?", N
, Spec_Id
);
1077 if Present
(Declarations
(N
))
1078 and then Has_Excluded_Declaration
(Spec_Id
, Declarations
(N
))
1083 if Present
(Handled_Statement_Sequence
(N
)) then
1084 if Present
(Exception_Handlers
(Handled_Statement_Sequence
(N
))) then
1086 ("cannot inline& (exception handler)?",
1087 First
(Exception_Handlers
(Handled_Statement_Sequence
(N
))),
1091 elsif Has_Excluded_Statement
1092 (Spec_Id
, Statements
(Handled_Statement_Sequence
(N
)))
1098 -- We do not inline a subprogram that is too large, unless it is marked
1099 -- Inline_Always or we are in GNATprove mode. This pragma does not
1100 -- suppress the other checks on inlining (forbidden declarations,
1103 if not (Has_Pragma_Inline_Always
(Spec_Id
) or else GNATprove_Mode
)
1104 and then List_Length
1105 (Statements
(Handled_Statement_Sequence
(N
))) > Max_Size
1107 Cannot_Inline
("cannot inline& (body too large)?", N
, Spec_Id
);
1111 if Has_Pending_Instantiation
then
1113 ("cannot inline& (forward instance within enclosing body)?",
1118 -- Within an instance, the body to inline must be treated as a nested
1119 -- generic, so that the proper global references are preserved.
1121 -- Note that we do not do this at the library level, because it is not
1122 -- needed, and furthermore this causes trouble if front end inlining
1123 -- is activated (-gnatN).
1125 if In_Instance
and then Scope
(Current_Scope
) /= Standard_Standard
then
1126 Save_Env
(Scope
(Current_Scope
), Scope
(Current_Scope
));
1127 Original_Body
:= Copy_Generic_Node
(N
, Empty
, True);
1129 Original_Body
:= Copy_Separate_Tree
(N
);
1132 -- We need to capture references to the formals in order to substitute
1133 -- the actuals at the point of inlining, i.e. instantiation. To treat
1134 -- the formals as globals to the body to inline, we nest it within a
1135 -- dummy parameterless subprogram, declared within the real one. To
1136 -- avoid generating an internal name (which is never public, and which
1137 -- affects serial numbers of other generated names), we use an internal
1138 -- symbol that cannot conflict with user declarations.
1140 Set_Parameter_Specifications
(Specification
(Original_Body
), No_List
);
1141 Set_Defining_Unit_Name
1142 (Specification
(Original_Body
),
1143 Make_Defining_Identifier
(Sloc
(N
), Name_uParent
));
1144 Set_Corresponding_Spec
(Original_Body
, Empty
);
1146 -- Remove all aspects/pragmas that have no meaining in an inlined body
1148 Remove_Aspects_And_Pragmas
(Original_Body
);
1150 Body_To_Analyze
:= Copy_Generic_Node
(Original_Body
, Empty
, False);
1152 -- Set return type of function, which is also global and does not need
1155 if Ekind
(Spec_Id
) = E_Function
then
1156 Set_Result_Definition
1157 (Specification
(Body_To_Analyze
),
1158 New_Occurrence_Of
(Etype
(Spec_Id
), Sloc
(N
)));
1161 if No
(Declarations
(N
)) then
1162 Set_Declarations
(N
, New_List
(Body_To_Analyze
));
1164 Append
(Body_To_Analyze
, Declarations
(N
));
1167 -- The body to inline is pre-analyzed. In GNATprove mode we must disable
1168 -- full analysis as well so that light expansion does not take place
1169 -- either, and name resolution is unaffected.
1171 Expander_Mode_Save_And_Set
(False);
1172 Full_Analysis
:= False;
1174 Analyze
(Body_To_Analyze
);
1175 Push_Scope
(Defining_Entity
(Body_To_Analyze
));
1176 Save_Global_References
(Original_Body
);
1178 Remove
(Body_To_Analyze
);
1180 Expander_Mode_Restore
;
1181 Full_Analysis
:= Analysis_Status
;
1183 -- Restore environment if previously saved
1185 if In_Instance
and then Scope
(Current_Scope
) /= Standard_Standard
then
1189 -- If secondary stack is used, there is no point in inlining. We have
1190 -- already issued the warning in this case, so nothing to do.
1192 if Uses_Secondary_Stack
(Body_To_Analyze
) then
1196 Set_Body_To_Inline
(Decl
, Original_Body
);
1197 Set_Ekind
(Defining_Entity
(Original_Body
), Ekind
(Spec_Id
));
1198 Set_Is_Inlined
(Spec_Id
);
1199 end Build_Body_To_Inline
;
1205 procedure Cannot_Inline
1209 Is_Serious
: Boolean := False)
1212 -- In GNATprove mode, inlining is the technical means by which the
1213 -- higher-level goal of contextual analysis is reached, so issue
1214 -- messages about failure to apply contextual analysis to a
1215 -- subprogram, rather than failure to inline it.
1218 and then Msg
(Msg
'First .. Msg
'First + 12) = "cannot inline"
1221 Len1
: constant Positive :=
1222 String (String'("cannot inline"))'Length;
1223 Len2 : constant Positive :=
1224 String (String'("info: no contextual analysis of"))'Length;
1226 New_Msg
: String (1 .. Msg
'Length + Len2
- Len1
);
1229 New_Msg
(1 .. Len2
) := "info: no contextual analysis of";
1230 New_Msg
(Len2
+ 1 .. Msg
'Length + Len2
- Len1
) :=
1231 Msg
(Msg
'First + Len1
.. Msg
'Last);
1232 Cannot_Inline
(New_Msg
, N
, Subp
, Is_Serious
);
1237 pragma Assert
(Msg
(Msg
'Last) = '?');
1239 -- Legacy front end inlining model
1241 if not Back_End_Inlining
then
1243 -- Do not emit warning if this is a predefined unit which is not
1244 -- the main unit. With validity checks enabled, some predefined
1245 -- subprograms may contain nested subprograms and become ineligible
1248 if Is_Predefined_File_Name
(Unit_File_Name
(Get_Source_Unit
(Subp
)))
1249 and then not In_Extended_Main_Source_Unit
(Subp
)
1253 -- In GNATprove mode, issue a warning, and indicate that the
1254 -- subprogram is not always inlined by setting flag Is_Inlined_Always
1257 elsif GNATprove_Mode
then
1258 Set_Is_Inlined_Always
(Subp
, False);
1259 Error_Msg_NE
(Msg
& "p?", N
, Subp
);
1261 elsif Has_Pragma_Inline_Always
(Subp
) then
1263 -- Remove last character (question mark) to make this into an
1264 -- error, because the Inline_Always pragma cannot be obeyed.
1266 Error_Msg_NE
(Msg
(Msg
'First .. Msg
'Last - 1), N
, Subp
);
1268 elsif Ineffective_Inline_Warnings
then
1269 Error_Msg_NE
(Msg
& "p?", N
, Subp
);
1272 -- New semantics relying on back end inlining
1274 elsif Is_Serious
then
1276 -- Remove last character (question mark) to make this into an error.
1278 Error_Msg_NE
(Msg
(Msg
'First .. Msg
'Last - 1), N
, Subp
);
1280 -- In GNATprove mode, issue a warning, and indicate that the subprogram
1281 -- is not always inlined by setting flag Is_Inlined_Always to False.
1283 elsif GNATprove_Mode
then
1284 Set_Is_Inlined_Always
(Subp
, False);
1285 Error_Msg_NE
(Msg
& "p?", N
, Subp
);
1289 -- Do not emit warning if this is a predefined unit which is not
1290 -- the main unit. This behavior is currently provided for backward
1291 -- compatibility but it will be removed when we enforce the
1292 -- strictness of the new rules.
1294 if Is_Predefined_File_Name
(Unit_File_Name
(Get_Source_Unit
(Subp
)))
1295 and then not In_Extended_Main_Source_Unit
(Subp
)
1299 elsif Has_Pragma_Inline_Always
(Subp
) then
1301 -- Emit a warning if this is a call to a runtime subprogram
1302 -- which is located inside a generic. Previously this call
1303 -- was silently skipped.
1305 if Is_Generic_Instance
(Subp
) then
1307 Gen_P
: constant Entity_Id
:= Generic_Parent
(Parent
(Subp
));
1309 if Is_Predefined_File_Name
1310 (Unit_File_Name
(Get_Source_Unit
(Gen_P
)))
1312 Set_Is_Inlined
(Subp
, False);
1313 Error_Msg_NE
(Msg
& "p?", N
, Subp
);
1319 -- Remove last character (question mark) to make this into an
1320 -- error, because the Inline_Always pragma cannot be obeyed.
1322 Error_Msg_NE
(Msg
(Msg
'First .. Msg
'Last - 1), N
, Subp
);
1325 Set_Is_Inlined
(Subp
, False);
1327 if Ineffective_Inline_Warnings
then
1328 Error_Msg_NE
(Msg
& "p?", N
, Subp
);
1334 --------------------------------------
1335 -- Can_Be_Inlined_In_GNATprove_Mode --
1336 --------------------------------------
1338 function Can_Be_Inlined_In_GNATprove_Mode
1339 (Spec_Id
: Entity_Id
;
1340 Body_Id
: Entity_Id
) return Boolean
1342 function Has_Formal_With_Discriminant_Dependent_Fields
1343 (Id
: Entity_Id
) return Boolean;
1344 -- Returns true if the subprogram has at least one formal parameter of
1345 -- an unconstrained record type with per-object constraints on component
1348 function Has_Some_Contract
(Id
: Entity_Id
) return Boolean;
1349 -- Returns True if subprogram Id has any contract (Pre, Post, Global,
1352 function Is_Unit_Subprogram
(Id
: Entity_Id
) return Boolean;
1353 -- Returns True if subprogram Id defines a compilation unit
1354 -- Shouldn't this be in Sem_Aux???
1356 function In_Package_Visible_Spec
(Id
: Node_Id
) return Boolean;
1357 -- Returns True if subprogram Id is defined in the visible part of a
1358 -- package specification.
1360 ---------------------------------------------------
1361 -- Has_Formal_With_Discriminant_Dependent_Fields --
1362 ---------------------------------------------------
1364 function Has_Formal_With_Discriminant_Dependent_Fields
1365 (Id
: Entity_Id
) return Boolean is
1367 function Has_Discriminant_Dependent_Component
1368 (Typ
: Entity_Id
) return Boolean;
1369 -- Determine whether unconstrained record type Typ has at least
1370 -- one component that depends on a discriminant.
1372 ------------------------------------------
1373 -- Has_Discriminant_Dependent_Component --
1374 ------------------------------------------
1376 function Has_Discriminant_Dependent_Component
1377 (Typ
: Entity_Id
) return Boolean
1382 -- Inspect all components of the record type looking for one
1383 -- that depends on a discriminant.
1385 Comp
:= First_Component
(Typ
);
1386 while Present
(Comp
) loop
1387 if Has_Discriminant_Dependent_Constraint
(Comp
) then
1391 Next_Component
(Comp
);
1395 end Has_Discriminant_Dependent_Component
;
1399 Subp_Id
: constant Entity_Id
:= Ultimate_Alias
(Id
);
1401 Formal_Typ
: Entity_Id
;
1403 -- Start of processing for
1404 -- Has_Formal_With_Discriminant_Dependent_Component
1407 -- Inspect all parameters of the subprogram looking for a formal
1408 -- of an unconstrained record type with at least one discriminant
1409 -- dependent component.
1411 Formal
:= First_Formal
(Subp_Id
);
1412 while Present
(Formal
) loop
1413 Formal_Typ
:= Etype
(Formal
);
1415 if Is_Record_Type
(Formal_Typ
)
1416 and then not Is_Constrained
(Formal_Typ
)
1417 and then Has_Discriminant_Dependent_Component
(Formal_Typ
)
1422 Next_Formal
(Formal
);
1426 end Has_Formal_With_Discriminant_Dependent_Fields
;
1428 -----------------------
1429 -- Has_Some_Contract --
1430 -----------------------
1432 function Has_Some_Contract
(Id
: Entity_Id
) return Boolean is
1436 -- A call to an expression function may precede the actual body which
1437 -- is inserted at the end of the enclosing declarations. Ensure that
1438 -- the related entity is decorated before inspecting the contract.
1440 if Is_Subprogram_Or_Generic_Subprogram
(Id
) then
1441 Items
:= Contract
(Id
);
1443 return Present
(Items
)
1444 and then (Present
(Pre_Post_Conditions
(Items
)) or else
1445 Present
(Contract_Test_Cases
(Items
)) or else
1446 Present
(Classifications
(Items
)));
1450 end Has_Some_Contract
;
1452 -----------------------------
1453 -- In_Package_Visible_Spec --
1454 -----------------------------
1456 function In_Package_Visible_Spec
(Id
: Node_Id
) return Boolean is
1457 Decl
: Node_Id
:= Parent
(Parent
(Id
));
1461 if Nkind
(Parent
(Id
)) = N_Defining_Program_Unit_Name
then
1462 Decl
:= Parent
(Decl
);
1467 return Nkind
(P
) = N_Package_Specification
1468 and then List_Containing
(Decl
) = Visible_Declarations
(P
);
1469 end In_Package_Visible_Spec
;
1471 ------------------------
1472 -- Is_Unit_Subprogram --
1473 ------------------------
1475 function Is_Unit_Subprogram
(Id
: Entity_Id
) return Boolean is
1476 Decl
: Node_Id
:= Parent
(Parent
(Id
));
1478 if Nkind
(Parent
(Id
)) = N_Defining_Program_Unit_Name
then
1479 Decl
:= Parent
(Decl
);
1482 return Nkind
(Parent
(Decl
)) = N_Compilation_Unit
;
1483 end Is_Unit_Subprogram
;
1485 -- Local declarations
1487 Id
: Entity_Id
; -- Procedure or function entity for the subprogram
1489 -- Start of processing for Can_Be_Inlined_In_GNATprove_Mode
1492 pragma Assert
(Present
(Spec_Id
) or else Present
(Body_Id
));
1494 if Present
(Spec_Id
) then
1500 -- Only local subprograms without contracts are inlined in GNATprove
1501 -- mode, as these are the subprograms which a user is not interested in
1502 -- analyzing in isolation, but rather in the context of their call. This
1503 -- is a convenient convention, that could be changed for an explicit
1504 -- pragma/aspect one day.
1506 -- In a number of special cases, inlining is not desirable or not
1507 -- possible, see below.
1509 -- Do not inline unit-level subprograms
1511 if Is_Unit_Subprogram
(Id
) then
1514 -- Do not inline subprograms declared in the visible part of a package
1516 elsif In_Package_Visible_Spec
(Id
) then
1519 -- Do not inline subprograms marked No_Return, possibly used for
1520 -- signaling errors, which GNATprove handles specially.
1522 elsif No_Return
(Id
) then
1525 -- Do not inline subprograms that have a contract on the spec or the
1526 -- body. Use the contract(s) instead in GNATprove.
1528 elsif (Present
(Spec_Id
) and then Has_Some_Contract
(Spec_Id
))
1530 (Present
(Body_Id
) and then Has_Some_Contract
(Body_Id
))
1534 -- Do not inline expression functions, which are directly inlined at the
1537 elsif (Present
(Spec_Id
) and then Is_Expression_Function
(Spec_Id
))
1539 (Present
(Body_Id
) and then Is_Expression_Function
(Body_Id
))
1543 -- Do not inline generic subprogram instances. The visibility rules of
1544 -- generic instances plays badly with inlining.
1546 elsif Is_Generic_Instance
(Spec_Id
) then
1549 -- Only inline subprograms whose spec is marked SPARK_Mode On. For
1550 -- the subprogram body, a similar check is performed after the body
1551 -- is analyzed, as this is where a pragma SPARK_Mode might be inserted.
1553 elsif Present
(Spec_Id
)
1555 (No
(SPARK_Pragma
(Spec_Id
))
1556 or else Get_SPARK_Mode_From_Pragma
(SPARK_Pragma
(Spec_Id
)) /= On
)
1560 -- Subprograms in generic instances are currently not inlined, to avoid
1561 -- problems with inlining of standard library subprograms.
1563 elsif Instantiation_Location
(Sloc
(Id
)) /= No_Location
then
1566 -- Do not inline predicate functions (treated specially by GNATprove)
1568 elsif Is_Predicate_Function
(Id
) then
1571 -- Do not inline subprograms with a parameter of an unconstrained
1572 -- record type if it has discrimiant dependent fields. Indeed, with
1573 -- such parameters, the frontend cannot always ensure type compliance
1574 -- in record component accesses (in particular with records containing
1577 elsif Has_Formal_With_Discriminant_Dependent_Fields
(Id
) then
1580 -- Otherwise, this is a subprogram declared inside the private part of a
1581 -- package, or inside a package body, or locally in a subprogram, and it
1582 -- does not have any contract. Inline it.
1587 end Can_Be_Inlined_In_GNATprove_Mode
;
1589 --------------------------------------------
1590 -- Check_And_Split_Unconstrained_Function --
1591 --------------------------------------------
1593 procedure Check_And_Split_Unconstrained_Function
1595 Spec_Id
: Entity_Id
;
1596 Body_Id
: Entity_Id
)
1598 procedure Build_Body_To_Inline
(N
: Node_Id
; Spec_Id
: Entity_Id
);
1599 -- Use generic machinery to build an unexpanded body for the subprogram.
1600 -- This body is subsequently used for inline expansions at call sites.
1602 function Can_Split_Unconstrained_Function
(N
: Node_Id
) return Boolean;
1603 -- Return true if we generate code for the function body N, the function
1604 -- body N has no local declarations and its unique statement is a single
1605 -- extended return statement with a handled statements sequence.
1607 procedure Generate_Subprogram_Body
1609 Body_To_Inline
: out Node_Id
);
1610 -- Generate a parameterless duplicate of subprogram body N. Occurrences
1611 -- of pragmas referencing the formals are removed since they have no
1612 -- meaning when the body is inlined and the formals are rewritten (the
1613 -- analysis of the non-inlined body will handle these pragmas properly).
1614 -- A new internal name is associated with Body_To_Inline.
1616 procedure Split_Unconstrained_Function
1618 Spec_Id
: Entity_Id
);
1619 -- N is an inlined function body that returns an unconstrained type and
1620 -- has a single extended return statement. Split N in two subprograms:
1621 -- a procedure P' and a function F'. The formals of P' duplicate the
1622 -- formals of N plus an extra formal which is used return a value;
1623 -- its body is composed by the declarations and list of statements
1624 -- of the extended return statement of N.
1626 --------------------------
1627 -- Build_Body_To_Inline --
1628 --------------------------
1630 procedure Build_Body_To_Inline
(N
: Node_Id
; Spec_Id
: Entity_Id
) is
1631 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Spec_Id
);
1632 Original_Body
: Node_Id
;
1633 Body_To_Analyze
: Node_Id
;
1636 pragma Assert
(Current_Scope
= Spec_Id
);
1638 -- Within an instance, the body to inline must be treated as a nested
1639 -- generic, so that the proper global references are preserved. We
1640 -- do not do this at the library level, because it is not needed, and
1641 -- furthermore this causes trouble if front end inlining is activated
1645 and then Scope
(Current_Scope
) /= Standard_Standard
1647 Save_Env
(Scope
(Current_Scope
), Scope
(Current_Scope
));
1650 -- We need to capture references to the formals in order
1651 -- to substitute the actuals at the point of inlining, i.e.
1652 -- instantiation. To treat the formals as globals to the body to
1653 -- inline, we nest it within a dummy parameterless subprogram,
1654 -- declared within the real one.
1656 Generate_Subprogram_Body
(N
, Original_Body
);
1657 Body_To_Analyze
:= Copy_Generic_Node
(Original_Body
, Empty
, False);
1659 -- Set return type of function, which is also global and does not
1660 -- need to be resolved.
1662 if Ekind
(Spec_Id
) = E_Function
then
1663 Set_Result_Definition
(Specification
(Body_To_Analyze
),
1664 New_Occurrence_Of
(Etype
(Spec_Id
), Sloc
(N
)));
1667 if No
(Declarations
(N
)) then
1668 Set_Declarations
(N
, New_List
(Body_To_Analyze
));
1670 Append_To
(Declarations
(N
), Body_To_Analyze
);
1673 Preanalyze
(Body_To_Analyze
);
1675 Push_Scope
(Defining_Entity
(Body_To_Analyze
));
1676 Save_Global_References
(Original_Body
);
1678 Remove
(Body_To_Analyze
);
1680 -- Restore environment if previously saved
1683 and then Scope
(Current_Scope
) /= Standard_Standard
1688 pragma Assert
(No
(Body_To_Inline
(Decl
)));
1689 Set_Body_To_Inline
(Decl
, Original_Body
);
1690 Set_Ekind
(Defining_Entity
(Original_Body
), Ekind
(Spec_Id
));
1691 end Build_Body_To_Inline
;
1693 --------------------------------------
1694 -- Can_Split_Unconstrained_Function --
1695 --------------------------------------
1697 function Can_Split_Unconstrained_Function
(N
: Node_Id
) return Boolean
1699 Ret_Node
: constant Node_Id
:=
1700 First
(Statements
(Handled_Statement_Sequence
(N
)));
1704 -- No user defined declarations allowed in the function except inside
1705 -- the unique return statement; implicit labels are the only allowed
1708 if not Is_Empty_List
(Declarations
(N
)) then
1709 D
:= First
(Declarations
(N
));
1710 while Present
(D
) loop
1711 if Nkind
(D
) /= N_Implicit_Label_Declaration
then
1719 -- We only split the inlined function when we are generating the code
1720 -- of its body; otherwise we leave duplicated split subprograms in
1721 -- the tree which (if referenced) generate wrong references at link
1724 return In_Extended_Main_Code_Unit
(N
)
1725 and then Present
(Ret_Node
)
1726 and then Nkind
(Ret_Node
) = N_Extended_Return_Statement
1727 and then No
(Next
(Ret_Node
))
1728 and then Present
(Handled_Statement_Sequence
(Ret_Node
));
1729 end Can_Split_Unconstrained_Function
;
1731 -----------------------------
1732 -- Generate_Body_To_Inline --
1733 -----------------------------
1735 procedure Generate_Subprogram_Body
1737 Body_To_Inline
: out Node_Id
)
1740 -- Within an instance, the body to inline must be treated as a nested
1741 -- generic, so that the proper global references are preserved.
1743 -- Note that we do not do this at the library level, because it
1744 -- is not needed, and furthermore this causes trouble if front
1745 -- end inlining is activated (-gnatN).
1748 and then Scope
(Current_Scope
) /= Standard_Standard
1750 Body_To_Inline
:= Copy_Generic_Node
(N
, Empty
, True);
1752 Body_To_Inline
:= Copy_Separate_Tree
(N
);
1755 -- Remove all aspects/pragmas that have no meaning in an inlined body
1757 Remove_Aspects_And_Pragmas
(Body_To_Inline
);
1759 -- We need to capture references to the formals in order
1760 -- to substitute the actuals at the point of inlining, i.e.
1761 -- instantiation. To treat the formals as globals to the body to
1762 -- inline, we nest it within a dummy parameterless subprogram,
1763 -- declared within the real one.
1765 Set_Parameter_Specifications
1766 (Specification
(Body_To_Inline
), No_List
);
1768 -- A new internal name is associated with Body_To_Inline to avoid
1769 -- conflicts when the non-inlined body N is analyzed.
1771 Set_Defining_Unit_Name
(Specification
(Body_To_Inline
),
1772 Make_Defining_Identifier
(Sloc
(N
), New_Internal_Name
('P')));
1773 Set_Corresponding_Spec
(Body_To_Inline
, Empty
);
1774 end Generate_Subprogram_Body
;
1776 ----------------------------------
1777 -- Split_Unconstrained_Function --
1778 ----------------------------------
1780 procedure Split_Unconstrained_Function
1782 Spec_Id
: Entity_Id
)
1784 Loc
: constant Source_Ptr
:= Sloc
(N
);
1785 Ret_Node
: constant Node_Id
:=
1786 First
(Statements
(Handled_Statement_Sequence
(N
)));
1787 Ret_Obj
: constant Node_Id
:=
1788 First
(Return_Object_Declarations
(Ret_Node
));
1790 procedure Build_Procedure
1791 (Proc_Id
: out Entity_Id
;
1792 Decl_List
: out List_Id
);
1793 -- Build a procedure containing the statements found in the extended
1794 -- return statement of the unconstrained function body N.
1796 ---------------------
1797 -- Build_Procedure --
1798 ---------------------
1800 procedure Build_Procedure
1801 (Proc_Id
: out Entity_Id
;
1802 Decl_List
: out List_Id
)
1805 Formal_List
: constant List_Id
:= New_List
;
1806 Proc_Spec
: Node_Id
;
1807 Proc_Body
: Node_Id
;
1808 Subp_Name
: constant Name_Id
:= New_Internal_Name
('F');
1809 Body_Decl_List
: List_Id
:= No_List
;
1810 Param_Type
: Node_Id
;
1813 if Nkind
(Object_Definition
(Ret_Obj
)) = N_Identifier
then
1815 New_Copy
(Object_Definition
(Ret_Obj
));
1818 New_Copy
(Subtype_Mark
(Object_Definition
(Ret_Obj
)));
1821 Append_To
(Formal_List
,
1822 Make_Parameter_Specification
(Loc
,
1823 Defining_Identifier
=>
1824 Make_Defining_Identifier
(Loc
,
1825 Chars
=> Chars
(Defining_Identifier
(Ret_Obj
))),
1826 In_Present
=> False,
1827 Out_Present
=> True,
1828 Null_Exclusion_Present
=> False,
1829 Parameter_Type
=> Param_Type
));
1831 Formal
:= First_Formal
(Spec_Id
);
1833 -- Note that we copy the parameter type rather than creating
1834 -- a reference to it, because it may be a class-wide entity
1835 -- that will not be retrieved by name.
1837 while Present
(Formal
) loop
1838 Append_To
(Formal_List
,
1839 Make_Parameter_Specification
(Loc
,
1840 Defining_Identifier
=>
1841 Make_Defining_Identifier
(Sloc
(Formal
),
1842 Chars
=> Chars
(Formal
)),
1843 In_Present
=> In_Present
(Parent
(Formal
)),
1844 Out_Present
=> Out_Present
(Parent
(Formal
)),
1845 Null_Exclusion_Present
=>
1846 Null_Exclusion_Present
(Parent
(Formal
)),
1848 New_Copy_Tree
(Parameter_Type
(Parent
(Formal
))),
1850 Copy_Separate_Tree
(Expression
(Parent
(Formal
)))));
1852 Next_Formal
(Formal
);
1855 Proc_Id
:= Make_Defining_Identifier
(Loc
, Chars
=> Subp_Name
);
1858 Make_Procedure_Specification
(Loc
,
1859 Defining_Unit_Name
=> Proc_Id
,
1860 Parameter_Specifications
=> Formal_List
);
1862 Decl_List
:= New_List
;
1864 Append_To
(Decl_List
,
1865 Make_Subprogram_Declaration
(Loc
, Proc_Spec
));
1867 -- Can_Convert_Unconstrained_Function checked that the function
1868 -- has no local declarations except implicit label declarations.
1869 -- Copy these declarations to the built procedure.
1871 if Present
(Declarations
(N
)) then
1872 Body_Decl_List
:= New_List
;
1879 D
:= First
(Declarations
(N
));
1880 while Present
(D
) loop
1881 pragma Assert
(Nkind
(D
) = N_Implicit_Label_Declaration
);
1884 Make_Implicit_Label_Declaration
(Loc
,
1885 Make_Defining_Identifier
(Loc
,
1886 Chars
=> Chars
(Defining_Identifier
(D
))),
1887 Label_Construct
=> Empty
);
1888 Append_To
(Body_Decl_List
, New_D
);
1895 pragma Assert
(Present
(Handled_Statement_Sequence
(Ret_Node
)));
1898 Make_Subprogram_Body
(Loc
,
1899 Specification
=> Copy_Separate_Tree
(Proc_Spec
),
1900 Declarations
=> Body_Decl_List
,
1901 Handled_Statement_Sequence
=>
1902 Copy_Separate_Tree
(Handled_Statement_Sequence
(Ret_Node
)));
1904 Set_Defining_Unit_Name
(Specification
(Proc_Body
),
1905 Make_Defining_Identifier
(Loc
, Subp_Name
));
1907 Append_To
(Decl_List
, Proc_Body
);
1908 end Build_Procedure
;
1912 New_Obj
: constant Node_Id
:= Copy_Separate_Tree
(Ret_Obj
);
1914 Proc_Id
: Entity_Id
;
1915 Proc_Call
: Node_Id
;
1917 -- Start of processing for Split_Unconstrained_Function
1920 -- Build the associated procedure, analyze it and insert it before
1921 -- the function body N.
1924 Scope
: constant Entity_Id
:= Current_Scope
;
1925 Decl_List
: List_Id
;
1928 Build_Procedure
(Proc_Id
, Decl_List
);
1929 Insert_Actions
(N
, Decl_List
);
1933 -- Build the call to the generated procedure
1936 Actual_List
: constant List_Id
:= New_List
;
1940 Append_To
(Actual_List
,
1941 New_Occurrence_Of
(Defining_Identifier
(New_Obj
), Loc
));
1943 Formal
:= First_Formal
(Spec_Id
);
1944 while Present
(Formal
) loop
1945 Append_To
(Actual_List
, New_Occurrence_Of
(Formal
, Loc
));
1947 -- Avoid spurious warning on unreferenced formals
1949 Set_Referenced
(Formal
);
1950 Next_Formal
(Formal
);
1954 Make_Procedure_Call_Statement
(Loc
,
1955 Name
=> New_Occurrence_Of
(Proc_Id
, Loc
),
1956 Parameter_Associations
=> Actual_List
);
1964 -- main_1__F1b (New_Obj, ...);
1969 Make_Block_Statement
(Loc
,
1970 Declarations
=> New_List
(New_Obj
),
1971 Handled_Statement_Sequence
=>
1972 Make_Handled_Sequence_Of_Statements
(Loc
,
1973 Statements
=> New_List
(
1977 Make_Simple_Return_Statement
(Loc
,
1980 (Defining_Identifier
(New_Obj
), Loc
)))));
1982 Rewrite
(Ret_Node
, Blk_Stmt
);
1983 end Split_Unconstrained_Function
;
1987 Decl
: constant Node_Id
:= Unit_Declaration_Node
(Spec_Id
);
1989 -- Start of processing for Check_And_Split_Unconstrained_Function
1992 pragma Assert
(Back_End_Inlining
1993 and then Ekind
(Spec_Id
) = E_Function
1994 and then Returns_Unconstrained_Type
(Spec_Id
)
1995 and then Comes_From_Source
(Body_Id
)
1996 and then (Has_Pragma_Inline_Always
(Spec_Id
)
1997 or else Optimization_Level
> 0));
1999 -- This routine must not be used in GNATprove mode since GNATprove
2000 -- relies on frontend inlining
2002 pragma Assert
(not GNATprove_Mode
);
2004 -- No need to split the function if we cannot generate the code
2006 if Serious_Errors_Detected
/= 0 then
2010 -- No action needed in stubs since the attribute Body_To_Inline
2013 if Nkind
(Decl
) = N_Subprogram_Body_Stub
then
2016 -- Cannot build the body to inline if the attribute is already set.
2017 -- This attribute may have been set if this is a subprogram renaming
2018 -- declarations (see Freeze.Build_Renamed_Body).
2020 elsif Present
(Body_To_Inline
(Decl
)) then
2023 -- Check excluded declarations
2025 elsif Present
(Declarations
(N
))
2026 and then Has_Excluded_Declaration
(Spec_Id
, Declarations
(N
))
2030 -- Check excluded statements. There is no need to protect us against
2031 -- exception handlers since they are supported by the GCC backend.
2033 elsif Present
(Handled_Statement_Sequence
(N
))
2034 and then Has_Excluded_Statement
2035 (Spec_Id
, Statements
(Handled_Statement_Sequence
(N
)))
2040 -- Build the body to inline only if really needed
2042 if Can_Split_Unconstrained_Function
(N
) then
2043 Split_Unconstrained_Function
(N
, Spec_Id
);
2044 Build_Body_To_Inline
(N
, Spec_Id
);
2045 Set_Is_Inlined
(Spec_Id
);
2047 end Check_And_Split_Unconstrained_Function
;
2049 -------------------------------------
2050 -- Check_Package_Body_For_Inlining --
2051 -------------------------------------
2053 procedure Check_Package_Body_For_Inlining
(N
: Node_Id
; P
: Entity_Id
) is
2054 Bname
: Unit_Name_Type
;
2059 -- Legacy implementation (relying on frontend inlining)
2061 if not Back_End_Inlining
2062 and then Is_Compilation_Unit
(P
)
2063 and then not Is_Generic_Instance
(P
)
2065 Bname
:= Get_Body_Name
(Get_Unit_Name
(Unit
(N
)));
2067 E
:= First_Entity
(P
);
2068 while Present
(E
) loop
2069 if Has_Pragma_Inline_Always
(E
)
2070 or else (Has_Pragma_Inline
(E
) and Front_End_Inlining
)
2072 if not Is_Loaded
(Bname
) then
2073 Load_Needed_Body
(N
, OK
);
2077 -- Check we are not trying to inline a parent whose body
2078 -- depends on a child, when we are compiling the body of
2079 -- the child. Otherwise we have a potential elaboration
2080 -- circularity with inlined subprograms and with
2081 -- Taft-Amendment types.
2084 Comp
: Node_Id
; -- Body just compiled
2085 Child_Spec
: Entity_Id
; -- Spec of main unit
2086 Ent
: Entity_Id
; -- For iteration
2087 With_Clause
: Node_Id
; -- Context of body.
2090 if Nkind
(Unit
(Cunit
(Main_Unit
))) = N_Package_Body
2091 and then Present
(Body_Entity
(P
))
2095 ((Unit
(Library_Unit
(Cunit
(Main_Unit
)))));
2098 Parent
(Unit_Declaration_Node
(Body_Entity
(P
)));
2100 -- Check whether the context of the body just
2101 -- compiled includes a child of itself, and that
2102 -- child is the spec of the main compilation.
2104 With_Clause
:= First
(Context_Items
(Comp
));
2105 while Present
(With_Clause
) loop
2106 if Nkind
(With_Clause
) = N_With_Clause
2108 Scope
(Entity
(Name
(With_Clause
))) = P
2110 Entity
(Name
(With_Clause
)) = Child_Spec
2112 Error_Msg_Node_2
:= Child_Spec
;
2114 ("body of & depends on child unit&??",
2117 ("\subprograms in body cannot be inlined??",
2120 -- Disable further inlining from this unit,
2121 -- and keep Taft-amendment types incomplete.
2123 Ent
:= First_Entity
(P
);
2124 while Present
(Ent
) loop
2126 and then Has_Completion_In_Body
(Ent
)
2128 Set_Full_View
(Ent
, Empty
);
2130 elsif Is_Subprogram
(Ent
) then
2131 Set_Is_Inlined
(Ent
, False);
2145 elsif Ineffective_Inline_Warnings
then
2146 Error_Msg_Unit_1
:= Bname
;
2148 ("unable to inline subprograms defined in $??", P
);
2149 Error_Msg_N
("\body not found??", P
);
2160 end Check_Package_Body_For_Inlining
;
2162 --------------------
2163 -- Cleanup_Scopes --
2164 --------------------
2166 procedure Cleanup_Scopes
is
2172 Elmt
:= First_Elmt
(To_Clean
);
2173 while Present
(Elmt
) loop
2174 Scop
:= Node
(Elmt
);
2176 if Ekind
(Scop
) = E_Entry
then
2177 Scop
:= Protected_Body_Subprogram
(Scop
);
2179 elsif Is_Subprogram
(Scop
)
2180 and then Is_Protected_Type
(Scope
(Scop
))
2181 and then Present
(Protected_Body_Subprogram
(Scop
))
2183 -- If a protected operation contains an instance, its cleanup
2184 -- operations have been delayed, and the subprogram has been
2185 -- rewritten in the expansion of the enclosing protected body. It
2186 -- is the corresponding subprogram that may require the cleanup
2187 -- operations, so propagate the information that triggers cleanup
2191 (Protected_Body_Subprogram
(Scop
),
2192 Uses_Sec_Stack
(Scop
));
2194 Scop
:= Protected_Body_Subprogram
(Scop
);
2197 if Ekind
(Scop
) = E_Block
then
2198 Decl
:= Parent
(Block_Node
(Scop
));
2201 Decl
:= Unit_Declaration_Node
(Scop
);
2203 if Nkind_In
(Decl
, N_Subprogram_Declaration
,
2204 N_Task_Type_Declaration
,
2205 N_Subprogram_Body_Stub
)
2207 Decl
:= Unit_Declaration_Node
(Corresponding_Body
(Decl
));
2212 Expand_Cleanup_Actions
(Decl
);
2215 Elmt
:= Next_Elmt
(Elmt
);
2219 -------------------------
2220 -- Expand_Inlined_Call --
2221 -------------------------
2223 procedure Expand_Inlined_Call
2226 Orig_Subp
: Entity_Id
)
2228 Loc
: constant Source_Ptr
:= Sloc
(N
);
2229 Is_Predef
: constant Boolean :=
2230 Is_Predefined_File_Name
2231 (Unit_File_Name
(Get_Source_Unit
(Subp
)));
2232 Orig_Bod
: constant Node_Id
:=
2233 Body_To_Inline
(Unit_Declaration_Node
(Subp
));
2237 Decls
: constant List_Id
:= New_List
;
2238 Exit_Lab
: Entity_Id
:= Empty
;
2245 Ret_Type
: Entity_Id
;
2248 -- The target of the call. If context is an assignment statement then
2249 -- this is the left-hand side of the assignment, else it is a temporary
2250 -- to which the return value is assigned prior to rewriting the call.
2253 -- A separate target used when the return type is unconstrained
2256 Temp_Typ
: Entity_Id
;
2258 Return_Object
: Entity_Id
:= Empty
;
2259 -- Entity in declaration in an extended_return_statement
2262 Is_Unc_Decl
: Boolean;
2263 -- If the type returned by the function is unconstrained and the call
2264 -- can be inlined, special processing is required.
2266 procedure Make_Exit_Label
;
2267 -- Build declaration for exit label to be used in Return statements,
2268 -- sets Exit_Lab (the label node) and Lab_Decl (corresponding implicit
2269 -- declaration). Does nothing if Exit_Lab already set.
2271 function Process_Formals
(N
: Node_Id
) return Traverse_Result
;
2272 -- Replace occurrence of a formal with the corresponding actual, or the
2273 -- thunk generated for it. Replace a return statement with an assignment
2274 -- to the target of the call, with appropriate conversions if needed.
2276 function Process_Sloc
(Nod
: Node_Id
) return Traverse_Result
;
2277 -- If the call being expanded is that of an internal subprogram, set the
2278 -- sloc of the generated block to that of the call itself, so that the
2279 -- expansion is skipped by the "next" command in gdb. Same processing
2280 -- for a subprogram in a predefined file, e.g. Ada.Tags. If
2281 -- Debug_Generated_Code is true, suppress this change to simplify our
2282 -- own development. Same in GNATprove mode, to ensure that warnings and
2283 -- diagnostics point to the proper location.
2285 procedure Reset_Dispatching_Calls
(N
: Node_Id
);
2286 -- In subtree N search for occurrences of dispatching calls that use the
2287 -- Ada 2005 Object.Operation notation and the object is a formal of the
2288 -- inlined subprogram. Reset the entity associated with Operation in all
2289 -- the found occurrences.
2291 procedure Rewrite_Function_Call
(N
: Node_Id
; Blk
: Node_Id
);
2292 -- If the function body is a single expression, replace call with
2293 -- expression, else insert block appropriately.
2295 procedure Rewrite_Procedure_Call
(N
: Node_Id
; Blk
: Node_Id
);
2296 -- If procedure body has no local variables, inline body without
2297 -- creating block, otherwise rewrite call with block.
2299 function Formal_Is_Used_Once
(Formal
: Entity_Id
) return Boolean;
2300 -- Determine whether a formal parameter is used only once in Orig_Bod
2302 ---------------------
2303 -- Make_Exit_Label --
2304 ---------------------
2306 procedure Make_Exit_Label
is
2307 Lab_Ent
: Entity_Id
;
2309 if No
(Exit_Lab
) then
2310 Lab_Ent
:= Make_Temporary
(Loc
, 'L');
2311 Lab_Id
:= New_Occurrence_Of
(Lab_Ent
, Loc
);
2312 Exit_Lab
:= Make_Label
(Loc
, Lab_Id
);
2314 Make_Implicit_Label_Declaration
(Loc
,
2315 Defining_Identifier
=> Lab_Ent
,
2316 Label_Construct
=> Exit_Lab
);
2318 end Make_Exit_Label
;
2320 ---------------------
2321 -- Process_Formals --
2322 ---------------------
2324 function Process_Formals
(N
: Node_Id
) return Traverse_Result
is
2330 if Is_Entity_Name
(N
) and then Present
(Entity
(N
)) then
2333 if Is_Formal
(E
) and then Scope
(E
) = Subp
then
2334 A
:= Renamed_Object
(E
);
2336 -- Rewrite the occurrence of the formal into an occurrence of
2337 -- the actual. Also establish visibility on the proper view of
2338 -- the actual's subtype for the body's context (if the actual's
2339 -- subtype is private at the call point but its full view is
2340 -- visible to the body, then the inlined tree here must be
2341 -- analyzed with the full view).
2343 if Is_Entity_Name
(A
) then
2344 Rewrite
(N
, New_Occurrence_Of
(Entity
(A
), Sloc
(N
)));
2345 Check_Private_View
(N
);
2347 elsif Nkind
(A
) = N_Defining_Identifier
then
2348 Rewrite
(N
, New_Occurrence_Of
(A
, Sloc
(N
)));
2349 Check_Private_View
(N
);
2354 Rewrite
(N
, New_Copy
(A
));
2360 elsif Is_Entity_Name
(N
)
2361 and then Present
(Return_Object
)
2362 and then Chars
(N
) = Chars
(Return_Object
)
2364 -- Occurrence within an extended return statement. The return
2365 -- object is local to the body been inlined, and thus the generic
2366 -- copy is not analyzed yet, so we match by name, and replace it
2367 -- with target of call.
2369 if Nkind
(Targ
) = N_Defining_Identifier
then
2370 Rewrite
(N
, New_Occurrence_Of
(Targ
, Loc
));
2372 Rewrite
(N
, New_Copy_Tree
(Targ
));
2377 elsif Nkind
(N
) = N_Simple_Return_Statement
then
2378 if No
(Expression
(N
)) then
2381 Make_Goto_Statement
(Loc
, Name
=> New_Copy
(Lab_Id
)));
2384 if Nkind
(Parent
(N
)) = N_Handled_Sequence_Of_Statements
2385 and then Nkind
(Parent
(Parent
(N
))) = N_Subprogram_Body
2387 -- Function body is a single expression. No need for
2393 Num_Ret
:= Num_Ret
+ 1;
2397 -- Because of the presence of private types, the views of the
2398 -- expression and the context may be different, so place an
2399 -- unchecked conversion to the context type to avoid spurious
2400 -- errors, e.g. when the expression is a numeric literal and
2401 -- the context is private. If the expression is an aggregate,
2402 -- use a qualified expression, because an aggregate is not a
2403 -- legal argument of a conversion. Ditto for numeric literals,
2404 -- which must be resolved to a specific type.
2406 if Nkind_In
(Expression
(N
), N_Aggregate
,
2412 Make_Qualified_Expression
(Sloc
(N
),
2413 Subtype_Mark
=> New_Occurrence_Of
(Ret_Type
, Sloc
(N
)),
2414 Expression
=> Relocate_Node
(Expression
(N
)));
2417 Unchecked_Convert_To
2418 (Ret_Type
, Relocate_Node
(Expression
(N
)));
2421 if Nkind
(Targ
) = N_Defining_Identifier
then
2423 Make_Assignment_Statement
(Loc
,
2424 Name
=> New_Occurrence_Of
(Targ
, Loc
),
2425 Expression
=> Ret
));
2428 Make_Assignment_Statement
(Loc
,
2429 Name
=> New_Copy
(Targ
),
2430 Expression
=> Ret
));
2433 Set_Assignment_OK
(Name
(N
));
2435 if Present
(Exit_Lab
) then
2437 Make_Goto_Statement
(Loc
, Name
=> New_Copy
(Lab_Id
)));
2443 -- An extended return becomes a block whose first statement is the
2444 -- assignment of the initial expression of the return object to the
2445 -- target of the call itself.
2447 elsif Nkind
(N
) = N_Extended_Return_Statement
then
2449 Return_Decl
: constant Entity_Id
:=
2450 First
(Return_Object_Declarations
(N
));
2454 Return_Object
:= Defining_Identifier
(Return_Decl
);
2456 if Present
(Expression
(Return_Decl
)) then
2457 if Nkind
(Targ
) = N_Defining_Identifier
then
2459 Make_Assignment_Statement
(Loc
,
2460 Name
=> New_Occurrence_Of
(Targ
, Loc
),
2461 Expression
=> Expression
(Return_Decl
));
2464 Make_Assignment_Statement
(Loc
,
2465 Name
=> New_Copy
(Targ
),
2466 Expression
=> Expression
(Return_Decl
));
2469 Set_Assignment_OK
(Name
(Assign
));
2471 if No
(Handled_Statement_Sequence
(N
)) then
2472 Set_Handled_Statement_Sequence
(N
,
2473 Make_Handled_Sequence_Of_Statements
(Loc
,
2474 Statements
=> New_List
));
2478 Statements
(Handled_Statement_Sequence
(N
)));
2482 Make_Block_Statement
(Loc
,
2483 Handled_Statement_Sequence
=>
2484 Handled_Statement_Sequence
(N
)));
2489 -- Remove pragma Unreferenced since it may refer to formals that
2490 -- are not visible in the inlined body, and in any case we will
2491 -- not be posting warnings on the inlined body so it is unneeded.
2493 elsif Nkind
(N
) = N_Pragma
2494 and then Pragma_Name
(N
) = Name_Unreferenced
2496 Rewrite
(N
, Make_Null_Statement
(Sloc
(N
)));
2502 end Process_Formals
;
2504 procedure Replace_Formals
is new Traverse_Proc
(Process_Formals
);
2510 function Process_Sloc
(Nod
: Node_Id
) return Traverse_Result
is
2512 if not Debug_Generated_Code
then
2513 Set_Sloc
(Nod
, Sloc
(N
));
2514 Set_Comes_From_Source
(Nod
, False);
2520 procedure Reset_Slocs
is new Traverse_Proc
(Process_Sloc
);
2522 ------------------------------
2523 -- Reset_Dispatching_Calls --
2524 ------------------------------
2526 procedure Reset_Dispatching_Calls
(N
: Node_Id
) is
2528 function Do_Reset
(N
: Node_Id
) return Traverse_Result
;
2529 -- Comment required ???
2535 function Do_Reset
(N
: Node_Id
) return Traverse_Result
is
2537 if Nkind
(N
) = N_Procedure_Call_Statement
2538 and then Nkind
(Name
(N
)) = N_Selected_Component
2539 and then Nkind
(Prefix
(Name
(N
))) = N_Identifier
2540 and then Is_Formal
(Entity
(Prefix
(Name
(N
))))
2541 and then Is_Dispatching_Operation
2542 (Entity
(Selector_Name
(Name
(N
))))
2544 Set_Entity
(Selector_Name
(Name
(N
)), Empty
);
2550 function Do_Reset_Calls
is new Traverse_Func
(Do_Reset
);
2554 Dummy
: constant Traverse_Result
:= Do_Reset_Calls
(N
);
2555 pragma Unreferenced
(Dummy
);
2557 -- Start of processing for Reset_Dispatching_Calls
2561 end Reset_Dispatching_Calls
;
2563 ---------------------------
2564 -- Rewrite_Function_Call --
2565 ---------------------------
2567 procedure Rewrite_Function_Call
(N
: Node_Id
; Blk
: Node_Id
) is
2568 HSS
: constant Node_Id
:= Handled_Statement_Sequence
(Blk
);
2569 Fst
: constant Node_Id
:= First
(Statements
(HSS
));
2572 -- Optimize simple case: function body is a single return statement,
2573 -- which has been expanded into an assignment.
2575 if Is_Empty_List
(Declarations
(Blk
))
2576 and then Nkind
(Fst
) = N_Assignment_Statement
2577 and then No
(Next
(Fst
))
2579 -- The function call may have been rewritten as the temporary
2580 -- that holds the result of the call, in which case remove the
2581 -- now useless declaration.
2583 if Nkind
(N
) = N_Identifier
2584 and then Nkind
(Parent
(Entity
(N
))) = N_Object_Declaration
2586 Rewrite
(Parent
(Entity
(N
)), Make_Null_Statement
(Loc
));
2589 Rewrite
(N
, Expression
(Fst
));
2591 elsif Nkind
(N
) = N_Identifier
2592 and then Nkind
(Parent
(Entity
(N
))) = N_Object_Declaration
2594 -- The block assigns the result of the call to the temporary
2596 Insert_After
(Parent
(Entity
(N
)), Blk
);
2598 -- If the context is an assignment, and the left-hand side is free of
2599 -- side-effects, the replacement is also safe.
2600 -- Can this be generalized further???
2602 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
2604 (Is_Entity_Name
(Name
(Parent
(N
)))
2606 (Nkind
(Name
(Parent
(N
))) = N_Explicit_Dereference
2607 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
)))))
2610 (Nkind
(Name
(Parent
(N
))) = N_Selected_Component
2611 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
))))))
2613 -- Replace assignment with the block
2616 Original_Assignment
: constant Node_Id
:= Parent
(N
);
2619 -- Preserve the original assignment node to keep the complete
2620 -- assignment subtree consistent enough for Analyze_Assignment
2621 -- to proceed (specifically, the original Lhs node must still
2622 -- have an assignment statement as its parent).
2624 -- We cannot rely on Original_Node to go back from the block
2625 -- node to the assignment node, because the assignment might
2626 -- already be a rewrite substitution.
2628 Discard_Node
(Relocate_Node
(Original_Assignment
));
2629 Rewrite
(Original_Assignment
, Blk
);
2632 elsif Nkind
(Parent
(N
)) = N_Object_Declaration
then
2634 -- A call to a function which returns an unconstrained type
2635 -- found in the expression initializing an object-declaration is
2636 -- expanded into a procedure call which must be added after the
2637 -- object declaration.
2639 if Is_Unc_Decl
and Back_End_Inlining
then
2640 Insert_Action_After
(Parent
(N
), Blk
);
2642 Set_Expression
(Parent
(N
), Empty
);
2643 Insert_After
(Parent
(N
), Blk
);
2646 elsif Is_Unc
and then not Back_End_Inlining
then
2647 Insert_Before
(Parent
(N
), Blk
);
2649 end Rewrite_Function_Call
;
2651 ----------------------------
2652 -- Rewrite_Procedure_Call --
2653 ----------------------------
2655 procedure Rewrite_Procedure_Call
(N
: Node_Id
; Blk
: Node_Id
) is
2656 HSS
: constant Node_Id
:= Handled_Statement_Sequence
(Blk
);
2659 -- If there is a transient scope for N, this will be the scope of the
2660 -- actions for N, and the statements in Blk need to be within this
2661 -- scope. For example, they need to have visibility on the constant
2662 -- declarations created for the formals.
2664 -- If N needs no transient scope, and if there are no declarations in
2665 -- the inlined body, we can do a little optimization and insert the
2666 -- statements for the body directly after N, and rewrite N to a
2667 -- null statement, instead of rewriting N into a full-blown block
2670 if not Scope_Is_Transient
2671 and then Is_Empty_List
(Declarations
(Blk
))
2673 Insert_List_After
(N
, Statements
(HSS
));
2674 Rewrite
(N
, Make_Null_Statement
(Loc
));
2678 end Rewrite_Procedure_Call
;
2680 -------------------------
2681 -- Formal_Is_Used_Once --
2682 -------------------------
2684 function Formal_Is_Used_Once
(Formal
: Entity_Id
) return Boolean is
2685 Use_Counter
: Int
:= 0;
2687 function Count_Uses
(N
: Node_Id
) return Traverse_Result
;
2688 -- Traverse the tree and count the uses of the formal parameter.
2689 -- In this case, for optimization purposes, we do not need to
2690 -- continue the traversal once more than one use is encountered.
2696 function Count_Uses
(N
: Node_Id
) return Traverse_Result
is
2698 -- The original node is an identifier
2700 if Nkind
(N
) = N_Identifier
2701 and then Present
(Entity
(N
))
2703 -- Original node's entity points to the one in the copied body
2705 and then Nkind
(Entity
(N
)) = N_Identifier
2706 and then Present
(Entity
(Entity
(N
)))
2708 -- The entity of the copied node is the formal parameter
2710 and then Entity
(Entity
(N
)) = Formal
2712 Use_Counter
:= Use_Counter
+ 1;
2714 if Use_Counter
> 1 then
2716 -- Denote more than one use and abandon the traversal
2727 procedure Count_Formal_Uses
is new Traverse_Proc
(Count_Uses
);
2729 -- Start of processing for Formal_Is_Used_Once
2732 Count_Formal_Uses
(Orig_Bod
);
2733 return Use_Counter
= 1;
2734 end Formal_Is_Used_Once
;
2736 -- Start of processing for Expand_Inlined_Call
2739 -- Initializations for old/new semantics
2741 if not Back_End_Inlining
then
2742 Is_Unc
:= Is_Array_Type
(Etype
(Subp
))
2743 and then not Is_Constrained
(Etype
(Subp
));
2744 Is_Unc_Decl
:= False;
2746 Is_Unc
:= Returns_Unconstrained_Type
(Subp
)
2747 and then Optimization_Level
> 0;
2748 Is_Unc_Decl
:= Nkind
(Parent
(N
)) = N_Object_Declaration
2752 -- Check for an illegal attempt to inline a recursive procedure. If the
2753 -- subprogram has parameters this is detected when trying to supply a
2754 -- binding for parameters that already have one. For parameterless
2755 -- subprograms this must be done explicitly.
2757 if In_Open_Scopes
(Subp
) then
2758 Error_Msg_N
("call to recursive subprogram cannot be inlined??", N
);
2759 Set_Is_Inlined
(Subp
, False);
2761 -- In GNATprove mode, issue a warning, and indicate that the
2762 -- subprogram is not always inlined by setting flag Is_Inlined_Always
2765 if GNATprove_Mode
then
2766 Set_Is_Inlined_Always
(Subp
, False);
2771 -- Skip inlining if this is not a true inlining since the attribute
2772 -- Body_To_Inline is also set for renamings (see sinfo.ads). For a
2773 -- true inlining, Orig_Bod has code rather than being an entity.
2775 elsif Nkind
(Orig_Bod
) in N_Entity
then
2778 -- Skip inlining if the function returns an unconstrained type using
2779 -- an extended return statement since this part of the new inlining
2780 -- model which is not yet supported by the current implementation. ???
2784 Nkind
(First
(Statements
(Handled_Statement_Sequence
(Orig_Bod
))))
2785 = N_Extended_Return_Statement
2786 and then not Back_End_Inlining
2791 if Nkind
(Orig_Bod
) = N_Defining_Identifier
2792 or else Nkind
(Orig_Bod
) = N_Defining_Operator_Symbol
2794 -- Subprogram is renaming_as_body. Calls occurring after the renaming
2795 -- can be replaced with calls to the renamed entity directly, because
2796 -- the subprograms are subtype conformant. If the renamed subprogram
2797 -- is an inherited operation, we must redo the expansion because
2798 -- implicit conversions may be needed. Similarly, if the renamed
2799 -- entity is inlined, expand the call for further optimizations.
2801 Set_Name
(N
, New_Occurrence_Of
(Orig_Bod
, Loc
));
2803 if Present
(Alias
(Orig_Bod
)) or else Is_Inlined
(Orig_Bod
) then
2810 -- Register the call in the list of inlined calls
2812 Append_New_Elmt
(N
, To
=> Inlined_Calls
);
2814 -- Use generic machinery to copy body of inlined subprogram, as if it
2815 -- were an instantiation, resetting source locations appropriately, so
2816 -- that nested inlined calls appear in the main unit.
2818 Save_Env
(Subp
, Empty
);
2819 Set_Copied_Sloc_For_Inlined_Body
(N
, Defining_Entity
(Orig_Bod
));
2823 if not Back_End_Inlining
then
2828 Bod
:= Copy_Generic_Node
(Orig_Bod
, Empty
, Instantiating
=> True);
2830 Make_Block_Statement
(Loc
,
2831 Declarations
=> Declarations
(Bod
),
2832 Handled_Statement_Sequence
=>
2833 Handled_Statement_Sequence
(Bod
));
2835 if No
(Declarations
(Bod
)) then
2836 Set_Declarations
(Blk
, New_List
);
2839 -- For the unconstrained case, capture the name of the local
2840 -- variable that holds the result. This must be the first
2841 -- declaration in the block, because its bounds cannot depend
2842 -- on local variables. Otherwise there is no way to declare the
2843 -- result outside of the block. Needless to say, in general the
2844 -- bounds will depend on the actuals in the call.
2846 -- If the context is an assignment statement, as is the case
2847 -- for the expansion of an extended return, the left-hand side
2848 -- provides bounds even if the return type is unconstrained.
2852 First_Decl
: Node_Id
;
2855 First_Decl
:= First
(Declarations
(Blk
));
2857 if Nkind
(First_Decl
) /= N_Object_Declaration
then
2861 if Nkind
(Parent
(N
)) /= N_Assignment_Statement
then
2862 Targ1
:= Defining_Identifier
(First_Decl
);
2864 Targ1
:= Name
(Parent
(N
));
2881 Copy_Generic_Node
(Orig_Bod
, Empty
, Instantiating
=> True);
2883 Make_Block_Statement
(Loc
,
2884 Declarations
=> Declarations
(Bod
),
2885 Handled_Statement_Sequence
=>
2886 Handled_Statement_Sequence
(Bod
));
2888 -- Inline a call to a function that returns an unconstrained type.
2889 -- The semantic analyzer checked that frontend-inlined functions
2890 -- returning unconstrained types have no declarations and have
2891 -- a single extended return statement. As part of its processing
2892 -- the function was split in two subprograms: a procedure P and
2893 -- a function F that has a block with a call to procedure P (see
2894 -- Split_Unconstrained_Function).
2900 (Statements
(Handled_Statement_Sequence
(Orig_Bod
)))) =
2904 Blk_Stmt
: constant Node_Id
:=
2905 First
(Statements
(Handled_Statement_Sequence
(Orig_Bod
)));
2906 First_Stmt
: constant Node_Id
:=
2907 First
(Statements
(Handled_Statement_Sequence
(Blk_Stmt
)));
2908 Second_Stmt
: constant Node_Id
:= Next
(First_Stmt
);
2912 (Nkind
(First_Stmt
) = N_Procedure_Call_Statement
2913 and then Nkind
(Second_Stmt
) = N_Simple_Return_Statement
2914 and then No
(Next
(Second_Stmt
)));
2919 (Statements
(Handled_Statement_Sequence
(Orig_Bod
))),
2920 Empty
, Instantiating
=> True);
2923 -- Capture the name of the local variable that holds the
2924 -- result. This must be the first declaration in the block,
2925 -- because its bounds cannot depend on local variables.
2926 -- Otherwise there is no way to declare the result outside
2927 -- of the block. Needless to say, in general the bounds will
2928 -- depend on the actuals in the call.
2930 if Nkind
(Parent
(N
)) /= N_Assignment_Statement
then
2931 Targ1
:= Defining_Identifier
(First
(Declarations
(Blk
)));
2933 -- If the context is an assignment statement, as is the case
2934 -- for the expansion of an extended return, the left-hand
2935 -- side provides bounds even if the return type is
2939 Targ1
:= Name
(Parent
(N
));
2944 if No
(Declarations
(Bod
)) then
2945 Set_Declarations
(Blk
, New_List
);
2950 -- If this is a derived function, establish the proper return type
2952 if Present
(Orig_Subp
) and then Orig_Subp
/= Subp
then
2953 Ret_Type
:= Etype
(Orig_Subp
);
2955 Ret_Type
:= Etype
(Subp
);
2958 -- Create temporaries for the actuals that are expressions, or that are
2959 -- scalars and require copying to preserve semantics.
2961 F
:= First_Formal
(Subp
);
2962 A
:= First_Actual
(N
);
2963 while Present
(F
) loop
2964 if Present
(Renamed_Object
(F
)) then
2966 -- If expander is active, it is an error to try to inline a
2967 -- recursive program. In GNATprove mode, just indicate that the
2968 -- inlining will not happen, and mark the subprogram as not always
2971 if GNATprove_Mode
then
2973 ("cannot inline call to recursive subprogram?", N
, Subp
);
2974 Set_Is_Inlined_Always
(Subp
, False);
2977 ("cannot inline call to recursive subprogram", N
);
2983 -- Reset Last_Assignment for any parameters of mode out or in out, to
2984 -- prevent spurious warnings about overwriting for assignments to the
2985 -- formal in the inlined code.
2987 if Is_Entity_Name
(A
) and then Ekind
(F
) /= E_In_Parameter
then
2988 Set_Last_Assignment
(Entity
(A
), Empty
);
2991 -- If the argument may be a controlling argument in a call within
2992 -- the inlined body, we must preserve its classwide nature to insure
2993 -- that dynamic dispatching take place subsequently. If the formal
2994 -- has a constraint it must be preserved to retain the semantics of
2997 if Is_Class_Wide_Type
(Etype
(F
))
2998 or else (Is_Access_Type
(Etype
(F
))
2999 and then Is_Class_Wide_Type
(Designated_Type
(Etype
(F
))))
3001 Temp_Typ
:= Etype
(F
);
3003 elsif Base_Type
(Etype
(F
)) = Base_Type
(Etype
(A
))
3004 and then Etype
(F
) /= Base_Type
(Etype
(F
))
3006 Temp_Typ
:= Etype
(F
);
3008 Temp_Typ
:= Etype
(A
);
3011 -- If the actual is a simple name or a literal, no need to
3012 -- create a temporary, object can be used directly.
3014 -- If the actual is a literal and the formal has its address taken,
3015 -- we cannot pass the literal itself as an argument, so its value
3016 -- must be captured in a temporary.
3018 if (Is_Entity_Name
(A
)
3020 (not Is_Scalar_Type
(Etype
(A
))
3021 or else Ekind
(Entity
(A
)) = E_Enumeration_Literal
))
3023 -- When the actual is an identifier and the corresponding formal is
3024 -- used only once in the original body, the formal can be substituted
3025 -- directly with the actual parameter.
3027 or else (Nkind
(A
) = N_Identifier
3028 and then Formal_Is_Used_Once
(F
))
3031 (Nkind_In
(A
, N_Real_Literal
,
3033 N_Character_Literal
)
3034 and then not Address_Taken
(F
))
3036 if Etype
(F
) /= Etype
(A
) then
3038 (F
, Unchecked_Convert_To
(Etype
(F
), Relocate_Node
(A
)));
3040 Set_Renamed_Object
(F
, A
);
3044 Temp
:= Make_Temporary
(Loc
, 'C');
3046 -- If the actual for an in/in-out parameter is a view conversion,
3047 -- make it into an unchecked conversion, given that an untagged
3048 -- type conversion is not a proper object for a renaming.
3050 -- In-out conversions that involve real conversions have already
3051 -- been transformed in Expand_Actuals.
3053 if Nkind
(A
) = N_Type_Conversion
3054 and then Ekind
(F
) /= E_In_Parameter
3057 Make_Unchecked_Type_Conversion
(Loc
,
3058 Subtype_Mark
=> New_Occurrence_Of
(Etype
(F
), Loc
),
3059 Expression
=> Relocate_Node
(Expression
(A
)));
3061 elsif Etype
(F
) /= Etype
(A
) then
3062 New_A
:= Unchecked_Convert_To
(Etype
(F
), Relocate_Node
(A
));
3063 Temp_Typ
:= Etype
(F
);
3066 New_A
:= Relocate_Node
(A
);
3069 Set_Sloc
(New_A
, Sloc
(N
));
3071 -- If the actual has a by-reference type, it cannot be copied,
3072 -- so its value is captured in a renaming declaration. Otherwise
3073 -- declare a local constant initialized with the actual.
3075 -- We also use a renaming declaration for expressions of an array
3076 -- type that is not bit-packed, both for efficiency reasons and to
3077 -- respect the semantics of the call: in most cases the original
3078 -- call will pass the parameter by reference, and thus the inlined
3079 -- code will have the same semantics.
3081 -- Finally, we need a renaming declaration in the case of limited
3082 -- types for which initialization cannot be by copy either.
3084 if Ekind
(F
) = E_In_Parameter
3085 and then not Is_By_Reference_Type
(Etype
(A
))
3086 and then not Is_Limited_Type
(Etype
(A
))
3088 (not Is_Array_Type
(Etype
(A
))
3089 or else not Is_Object_Reference
(A
)
3090 or else Is_Bit_Packed_Array
(Etype
(A
)))
3093 Make_Object_Declaration
(Loc
,
3094 Defining_Identifier
=> Temp
,
3095 Constant_Present
=> True,
3096 Object_Definition
=> New_Occurrence_Of
(Temp_Typ
, Loc
),
3097 Expression
=> New_A
);
3100 Make_Object_Renaming_Declaration
(Loc
,
3101 Defining_Identifier
=> Temp
,
3102 Subtype_Mark
=> New_Occurrence_Of
(Temp_Typ
, Loc
),
3106 Append
(Decl
, Decls
);
3107 Set_Renamed_Object
(F
, Temp
);
3114 -- Establish target of function call. If context is not assignment or
3115 -- declaration, create a temporary as a target. The declaration for the
3116 -- temporary may be subsequently optimized away if the body is a single
3117 -- expression, or if the left-hand side of the assignment is simple
3118 -- enough, i.e. an entity or an explicit dereference of one.
3120 if Ekind
(Subp
) = E_Function
then
3121 if Nkind
(Parent
(N
)) = N_Assignment_Statement
3122 and then Is_Entity_Name
(Name
(Parent
(N
)))
3124 Targ
:= Name
(Parent
(N
));
3126 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
3127 and then Nkind
(Name
(Parent
(N
))) = N_Explicit_Dereference
3128 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
))))
3130 Targ
:= Name
(Parent
(N
));
3132 elsif Nkind
(Parent
(N
)) = N_Assignment_Statement
3133 and then Nkind
(Name
(Parent
(N
))) = N_Selected_Component
3134 and then Is_Entity_Name
(Prefix
(Name
(Parent
(N
))))
3136 Targ
:= New_Copy_Tree
(Name
(Parent
(N
)));
3138 elsif Nkind
(Parent
(N
)) = N_Object_Declaration
3139 and then Is_Limited_Type
(Etype
(Subp
))
3141 Targ
:= Defining_Identifier
(Parent
(N
));
3143 -- New semantics: In an object declaration avoid an extra copy
3144 -- of the result of a call to an inlined function that returns
3145 -- an unconstrained type
3147 elsif Back_End_Inlining
3148 and then Nkind
(Parent
(N
)) = N_Object_Declaration
3151 Targ
:= Defining_Identifier
(Parent
(N
));
3154 -- Replace call with temporary and create its declaration
3156 Temp
:= Make_Temporary
(Loc
, 'C');
3157 Set_Is_Internal
(Temp
);
3159 -- For the unconstrained case, the generated temporary has the
3160 -- same constrained declaration as the result variable. It may
3161 -- eventually be possible to remove that temporary and use the
3162 -- result variable directly.
3164 if Is_Unc
and then Nkind
(Parent
(N
)) /= N_Assignment_Statement
3167 Make_Object_Declaration
(Loc
,
3168 Defining_Identifier
=> Temp
,
3169 Object_Definition
=>
3170 New_Copy_Tree
(Object_Definition
(Parent
(Targ1
))));
3172 Replace_Formals
(Decl
);
3176 Make_Object_Declaration
(Loc
,
3177 Defining_Identifier
=> Temp
,
3178 Object_Definition
=> New_Occurrence_Of
(Ret_Type
, Loc
));
3180 Set_Etype
(Temp
, Ret_Type
);
3183 Set_No_Initialization
(Decl
);
3184 Append
(Decl
, Decls
);
3185 Rewrite
(N
, New_Occurrence_Of
(Temp
, Loc
));
3190 Insert_Actions
(N
, Decls
);
3194 -- Special management for inlining a call to a function that returns
3195 -- an unconstrained type and initializes an object declaration: we
3196 -- avoid generating undesired extra calls and goto statements.
3199 -- function Func (...) return ...
3202 -- Result : String (1 .. 4);
3204 -- Proc (Result, ...);
3209 -- Result : String := Func (...);
3211 -- Replace this object declaration by:
3213 -- Result : String (1 .. 4);
3214 -- Proc (Result, ...);
3216 Remove_Homonym
(Targ
);
3219 Make_Object_Declaration
3221 Defining_Identifier
=> Targ
,
3222 Object_Definition
=>
3223 New_Copy_Tree
(Object_Definition
(Parent
(Targ1
))));
3224 Replace_Formals
(Decl
);
3225 Rewrite
(Parent
(N
), Decl
);
3226 Analyze
(Parent
(N
));
3228 -- Avoid spurious warnings since we know that this declaration is
3229 -- referenced by the procedure call.
3231 Set_Never_Set_In_Source
(Targ
, False);
3233 -- Remove the local declaration of the extended return stmt from the
3236 Remove
(Parent
(Targ1
));
3238 -- Update the reference to the result (since we have rewriten the
3239 -- object declaration)
3242 Blk_Call_Stmt
: Node_Id
;
3245 -- Capture the call to the procedure
3248 First
(Statements
(Handled_Statement_Sequence
(Blk
)));
3250 (Nkind
(Blk_Call_Stmt
) = N_Procedure_Call_Statement
);
3252 Remove
(First
(Parameter_Associations
(Blk_Call_Stmt
)));
3253 Prepend_To
(Parameter_Associations
(Blk_Call_Stmt
),
3254 New_Occurrence_Of
(Targ
, Loc
));
3257 -- Remove the return statement
3260 (Nkind
(Last
(Statements
(Handled_Statement_Sequence
(Blk
)))) =
3261 N_Simple_Return_Statement
);
3263 Remove
(Last
(Statements
(Handled_Statement_Sequence
(Blk
))));
3266 -- Traverse the tree and replace formals with actuals or their thunks.
3267 -- Attach block to tree before analysis and rewriting.
3269 Replace_Formals
(Blk
);
3270 Set_Parent
(Blk
, N
);
3272 if GNATprove_Mode
then
3275 elsif not Comes_From_Source
(Subp
) or else Is_Predef
then
3281 -- No action needed since return statement has been already removed
3285 elsif Present
(Exit_Lab
) then
3287 -- If the body was a single expression, the single return statement
3288 -- and the corresponding label are useless.
3292 Nkind
(Last
(Statements
(Handled_Statement_Sequence
(Blk
)))) =
3295 Remove
(Last
(Statements
(Handled_Statement_Sequence
(Blk
))));
3297 Append
(Lab_Decl
, (Declarations
(Blk
)));
3298 Append
(Exit_Lab
, Statements
(Handled_Statement_Sequence
(Blk
)));
3302 -- Analyze Blk with In_Inlined_Body set, to avoid spurious errors
3303 -- on conflicting private views that Gigi would ignore. If this is a
3304 -- predefined unit, analyze with checks off, as is done in the non-
3305 -- inlined run-time units.
3308 I_Flag
: constant Boolean := In_Inlined_Body
;
3311 In_Inlined_Body
:= True;
3315 Style
: constant Boolean := Style_Check
;
3318 Style_Check
:= False;
3320 -- Search for dispatching calls that use the Object.Operation
3321 -- notation using an Object that is a parameter of the inlined
3322 -- function. We reset the decoration of Operation to force
3323 -- the reanalysis of the inlined dispatching call because
3324 -- the actual object has been inlined.
3326 Reset_Dispatching_Calls
(Blk
);
3328 Analyze
(Blk
, Suppress
=> All_Checks
);
3329 Style_Check
:= Style
;
3336 In_Inlined_Body
:= I_Flag
;
3339 if Ekind
(Subp
) = E_Procedure
then
3340 Rewrite_Procedure_Call
(N
, Blk
);
3343 Rewrite_Function_Call
(N
, Blk
);
3348 -- For the unconstrained case, the replacement of the call has been
3349 -- made prior to the complete analysis of the generated declarations.
3350 -- Propagate the proper type now.
3353 if Nkind
(N
) = N_Identifier
then
3354 Set_Etype
(N
, Etype
(Entity
(N
)));
3356 Set_Etype
(N
, Etype
(Targ1
));
3363 -- Cleanup mapping between formals and actuals for other expansions
3365 F
:= First_Formal
(Subp
);
3366 while Present
(F
) loop
3367 Set_Renamed_Object
(F
, Empty
);
3370 end Expand_Inlined_Call
;
3372 --------------------------
3373 -- Get_Code_Unit_Entity --
3374 --------------------------
3376 function Get_Code_Unit_Entity
(E
: Entity_Id
) return Entity_Id
is
3377 Unit
: Entity_Id
:= Cunit_Entity
(Get_Code_Unit
(E
));
3380 if Ekind
(Unit
) = E_Package_Body
then
3381 Unit
:= Spec_Entity
(Unit
);
3385 end Get_Code_Unit_Entity
;
3387 ------------------------------
3388 -- Has_Excluded_Declaration --
3389 ------------------------------
3391 function Has_Excluded_Declaration
3393 Decls
: List_Id
) return Boolean
3397 function Is_Unchecked_Conversion
(D
: Node_Id
) return Boolean;
3398 -- Nested subprograms make a given body ineligible for inlining, but
3399 -- we make an exception for instantiations of unchecked conversion.
3400 -- The body has not been analyzed yet, so check the name, and verify
3401 -- that the visible entity with that name is the predefined unit.
3403 -----------------------------
3404 -- Is_Unchecked_Conversion --
3405 -----------------------------
3407 function Is_Unchecked_Conversion
(D
: Node_Id
) return Boolean is
3408 Id
: constant Node_Id
:= Name
(D
);
3412 if Nkind
(Id
) = N_Identifier
3413 and then Chars
(Id
) = Name_Unchecked_Conversion
3415 Conv
:= Current_Entity
(Id
);
3417 elsif Nkind_In
(Id
, N_Selected_Component
, N_Expanded_Name
)
3418 and then Chars
(Selector_Name
(Id
)) = Name_Unchecked_Conversion
3420 Conv
:= Current_Entity
(Selector_Name
(Id
));
3425 return Present
(Conv
)
3426 and then Is_Predefined_File_Name
3427 (Unit_File_Name
(Get_Source_Unit
(Conv
)))
3428 and then Is_Intrinsic_Subprogram
(Conv
);
3429 end Is_Unchecked_Conversion
;
3431 -- Start of processing for Has_Excluded_Declaration
3434 -- No action needed if the check is not needed
3436 if not Check_Inlining_Restrictions
then
3441 while Present
(D
) loop
3443 -- First declarations universally excluded
3445 if Nkind
(D
) = N_Package_Declaration
then
3447 ("cannot inline & (nested package declaration)?", D
, Subp
);
3450 elsif Nkind
(D
) = N_Package_Instantiation
then
3452 ("cannot inline & (nested package instantiation)?", D
, Subp
);
3456 -- Then declarations excluded only for front end inlining
3458 if Back_End_Inlining
then
3461 elsif Nkind
(D
) = N_Task_Type_Declaration
3462 or else Nkind
(D
) = N_Single_Task_Declaration
3465 ("cannot inline & (nested task type declaration)?", D
, Subp
);
3468 elsif Nkind
(D
) = N_Protected_Type_Declaration
3469 or else Nkind
(D
) = N_Single_Protected_Declaration
3472 ("cannot inline & (nested protected type declaration)?",
3476 elsif Nkind
(D
) = N_Subprogram_Body
then
3478 ("cannot inline & (nested subprogram)?", D
, Subp
);
3481 elsif Nkind
(D
) = N_Function_Instantiation
3482 and then not Is_Unchecked_Conversion
(D
)
3485 ("cannot inline & (nested function instantiation)?", D
, Subp
);
3488 elsif Nkind
(D
) = N_Procedure_Instantiation
then
3490 ("cannot inline & (nested procedure instantiation)?", D
, Subp
);
3493 -- Subtype declarations with predicates will generate predicate
3494 -- functions, i.e. nested subprogram bodies, so inlining is not
3497 elsif Nkind
(D
) = N_Subtype_Declaration
3498 and then Present
(Aspect_Specifications
(D
))
3505 A
:= First
(Aspect_Specifications
(D
));
3506 while Present
(A
) loop
3507 A_Id
:= Get_Aspect_Id
(Chars
(Identifier
(A
)));
3509 if A_Id
= Aspect_Predicate
3510 or else A_Id
= Aspect_Static_Predicate
3511 or else A_Id
= Aspect_Dynamic_Predicate
3514 ("cannot inline & (subtype declaration with "
3515 & "predicate)?", D
, Subp
);
3528 end Has_Excluded_Declaration
;
3530 ----------------------------
3531 -- Has_Excluded_Statement --
3532 ----------------------------
3534 function Has_Excluded_Statement
3536 Stats
: List_Id
) return Boolean
3542 -- No action needed if the check is not needed
3544 if not Check_Inlining_Restrictions
then
3549 while Present
(S
) loop
3550 if Nkind_In
(S
, N_Abort_Statement
,
3551 N_Asynchronous_Select
,
3552 N_Conditional_Entry_Call
,
3553 N_Delay_Relative_Statement
,
3554 N_Delay_Until_Statement
,
3559 ("cannot inline & (non-allowed statement)?", S
, Subp
);
3562 elsif Nkind
(S
) = N_Block_Statement
then
3563 if Present
(Declarations
(S
))
3564 and then Has_Excluded_Declaration
(Subp
, Declarations
(S
))
3568 elsif Present
(Handled_Statement_Sequence
(S
)) then
3569 if not Back_End_Inlining
3572 (Exception_Handlers
(Handled_Statement_Sequence
(S
)))
3575 ("cannot inline& (exception handler)?",
3576 First
(Exception_Handlers
3577 (Handled_Statement_Sequence
(S
))),
3581 elsif Has_Excluded_Statement
3582 (Subp
, Statements
(Handled_Statement_Sequence
(S
)))
3588 elsif Nkind
(S
) = N_Case_Statement
then
3589 E
:= First
(Alternatives
(S
));
3590 while Present
(E
) loop
3591 if Has_Excluded_Statement
(Subp
, Statements
(E
)) then
3598 elsif Nkind
(S
) = N_If_Statement
then
3599 if Has_Excluded_Statement
(Subp
, Then_Statements
(S
)) then
3603 if Present
(Elsif_Parts
(S
)) then
3604 E
:= First
(Elsif_Parts
(S
));
3605 while Present
(E
) loop
3606 if Has_Excluded_Statement
(Subp
, Then_Statements
(E
)) then
3614 if Present
(Else_Statements
(S
))
3615 and then Has_Excluded_Statement
(Subp
, Else_Statements
(S
))
3620 elsif Nkind
(S
) = N_Loop_Statement
3621 and then Has_Excluded_Statement
(Subp
, Statements
(S
))
3625 elsif Nkind
(S
) = N_Extended_Return_Statement
then
3626 if Present
(Handled_Statement_Sequence
(S
))
3628 Has_Excluded_Statement
3629 (Subp
, Statements
(Handled_Statement_Sequence
(S
)))
3633 elsif not Back_End_Inlining
3634 and then Present
(Handled_Statement_Sequence
(S
))
3636 Present
(Exception_Handlers
3637 (Handled_Statement_Sequence
(S
)))
3640 ("cannot inline& (exception handler)?",
3641 First
(Exception_Handlers
(Handled_Statement_Sequence
(S
))),
3651 end Has_Excluded_Statement
;
3653 --------------------------
3654 -- Has_Initialized_Type --
3655 --------------------------
3657 function Has_Initialized_Type
(E
: Entity_Id
) return Boolean is
3658 E_Body
: constant Node_Id
:= Subprogram_Body
(E
);
3662 if No
(E_Body
) then -- imported subprogram
3666 Decl
:= First
(Declarations
(E_Body
));
3667 while Present
(Decl
) loop
3668 if Nkind
(Decl
) = N_Full_Type_Declaration
3669 and then Present
(Init_Proc
(Defining_Identifier
(Decl
)))
3679 end Has_Initialized_Type
;
3681 -----------------------
3682 -- Has_Single_Return --
3683 -----------------------
3685 function Has_Single_Return
(N
: Node_Id
) return Boolean is
3686 Return_Statement
: Node_Id
:= Empty
;
3688 function Check_Return
(N
: Node_Id
) return Traverse_Result
;
3694 function Check_Return
(N
: Node_Id
) return Traverse_Result
is
3696 if Nkind
(N
) = N_Simple_Return_Statement
then
3697 if Present
(Expression
(N
))
3698 and then Is_Entity_Name
(Expression
(N
))
3700 if No
(Return_Statement
) then
3701 Return_Statement
:= N
;
3704 elsif Chars
(Expression
(N
)) =
3705 Chars
(Expression
(Return_Statement
))
3713 -- A return statement within an extended return is a noop
3716 elsif No
(Expression
(N
))
3718 Nkind
(Parent
(Parent
(N
))) = N_Extended_Return_Statement
3723 -- Expression has wrong form
3728 -- We can only inline a build-in-place function if it has a single
3731 elsif Nkind
(N
) = N_Extended_Return_Statement
then
3732 if No
(Return_Statement
) then
3733 Return_Statement
:= N
;
3745 function Check_All_Returns
is new Traverse_Func
(Check_Return
);
3747 -- Start of processing for Has_Single_Return
3750 if Check_All_Returns
(N
) /= OK
then
3753 elsif Nkind
(Return_Statement
) = N_Extended_Return_Statement
then
3757 return Present
(Declarations
(N
))
3758 and then Present
(First
(Declarations
(N
)))
3759 and then Chars
(Expression
(Return_Statement
)) =
3760 Chars
(Defining_Identifier
(First
(Declarations
(N
))));
3762 end Has_Single_Return
;
3764 -----------------------------
3765 -- In_Main_Unit_Or_Subunit --
3766 -----------------------------
3768 function In_Main_Unit_Or_Subunit
(E
: Entity_Id
) return Boolean is
3769 Comp
: Node_Id
:= Cunit
(Get_Code_Unit
(E
));
3772 -- Check whether the subprogram or package to inline is within the main
3773 -- unit or its spec or within a subunit. In either case there are no
3774 -- additional bodies to process. If the subprogram appears in a parent
3775 -- of the current unit, the check on whether inlining is possible is
3776 -- done in Analyze_Inlined_Bodies.
3778 while Nkind
(Unit
(Comp
)) = N_Subunit
loop
3779 Comp
:= Library_Unit
(Comp
);
3782 return Comp
= Cunit
(Main_Unit
)
3783 or else Comp
= Library_Unit
(Cunit
(Main_Unit
));
3784 end In_Main_Unit_Or_Subunit
;
3790 procedure Initialize
is
3792 Pending_Descriptor
.Init
;
3793 Pending_Instantiations
.Init
;
3794 Inlined_Bodies
.Init
;
3798 for J
in Hash_Headers
'Range loop
3799 Hash_Headers
(J
) := No_Subp
;
3802 Inlined_Calls
:= No_Elist
;
3803 Backend_Calls
:= No_Elist
;
3804 Backend_Inlined_Subps
:= No_Elist
;
3805 Backend_Not_Inlined_Subps
:= No_Elist
;
3808 ------------------------
3809 -- Instantiate_Bodies --
3810 ------------------------
3812 -- Generic bodies contain all the non-local references, so an
3813 -- instantiation does not need any more context than Standard
3814 -- itself, even if the instantiation appears in an inner scope.
3815 -- Generic associations have verified that the contract model is
3816 -- satisfied, so that any error that may occur in the analysis of
3817 -- the body is an internal error.
3819 procedure Instantiate_Bodies
is
3821 Info
: Pending_Body_Info
;
3824 if Serious_Errors_Detected
= 0 then
3825 Expander_Active
:= (Operating_Mode
= Opt
.Generate_Code
);
3826 Push_Scope
(Standard_Standard
);
3827 To_Clean
:= New_Elmt_List
;
3829 if Is_Generic_Unit
(Cunit_Entity
(Main_Unit
)) then
3833 -- A body instantiation may generate additional instantiations, so
3834 -- the following loop must scan to the end of a possibly expanding
3835 -- set (that's why we can't simply use a FOR loop here).
3838 while J
<= Pending_Instantiations
.Last
3839 and then Serious_Errors_Detected
= 0
3841 Info
:= Pending_Instantiations
.Table
(J
);
3843 -- If the instantiation node is absent, it has been removed
3844 -- as part of unreachable code.
3846 if No
(Info
.Inst_Node
) then
3849 elsif Nkind
(Info
.Act_Decl
) = N_Package_Declaration
then
3850 Instantiate_Package_Body
(Info
);
3851 Add_Scope_To_Clean
(Defining_Entity
(Info
.Act_Decl
));
3854 Instantiate_Subprogram_Body
(Info
);
3860 -- Reset the table of instantiations. Additional instantiations
3861 -- may be added through inlining, when additional bodies are
3864 Pending_Instantiations
.Init
;
3866 -- We can now complete the cleanup actions of scopes that contain
3867 -- pending instantiations (skipped for generic units, since we
3868 -- never need any cleanups in generic units).
3869 -- pending instantiations.
3872 and then not Is_Generic_Unit
(Main_Unit_Entity
)
3875 elsif Is_Generic_Unit
(Cunit_Entity
(Main_Unit
)) then
3881 end Instantiate_Bodies
;
3887 function Is_Nested
(E
: Entity_Id
) return Boolean is
3892 while Scop
/= Standard_Standard
loop
3893 if Ekind
(Scop
) in Subprogram_Kind
then
3896 elsif Ekind
(Scop
) = E_Task_Type
3897 or else Ekind
(Scop
) = E_Entry
3898 or else Ekind
(Scop
) = E_Entry_Family
3903 Scop
:= Scope
(Scop
);
3909 ------------------------
3910 -- List_Inlining_Info --
3911 ------------------------
3913 procedure List_Inlining_Info
is
3919 if not Debug_Flag_Dot_J
then
3923 -- Generate listing of calls inlined by the frontend
3925 if Present
(Inlined_Calls
) then
3927 Elmt
:= First_Elmt
(Inlined_Calls
);
3928 while Present
(Elmt
) loop
3931 if In_Extended_Main_Code_Unit
(Nod
) then
3935 Write_Str
("List of calls inlined by the frontend");
3942 Write_Location
(Sloc
(Nod
));
3951 -- Generate listing of calls passed to the backend
3953 if Present
(Backend_Calls
) then
3956 Elmt
:= First_Elmt
(Backend_Calls
);
3957 while Present
(Elmt
) loop
3960 if In_Extended_Main_Code_Unit
(Nod
) then
3964 Write_Str
("List of inlined calls passed to the backend");
3971 Write_Location
(Sloc
(Nod
));
3979 -- Generate listing of subprograms passed to the backend
3981 if Present
(Backend_Inlined_Subps
) and then Back_End_Inlining
then
3984 Elmt
:= First_Elmt
(Backend_Inlined_Subps
);
3985 while Present
(Elmt
) loop
3992 ("List of inlined subprograms passed to the backend");
3999 Write_Name
(Chars
(Nod
));
4001 Write_Location
(Sloc
(Nod
));
4009 -- Generate listing of subprograms that cannot be inlined by the backend
4011 if Present
(Backend_Not_Inlined_Subps
) and then Back_End_Inlining
then
4014 Elmt
:= First_Elmt
(Backend_Not_Inlined_Subps
);
4015 while Present
(Elmt
) loop
4022 ("List of subprograms that cannot be inlined by the backend");
4029 Write_Name
(Chars
(Nod
));
4031 Write_Location
(Sloc
(Nod
));
4038 end List_Inlining_Info
;
4046 Pending_Instantiations
.Locked
:= True;
4047 Inlined_Bodies
.Locked
:= True;
4048 Successors
.Locked
:= True;
4049 Inlined
.Locked
:= True;
4050 Pending_Instantiations
.Release
;
4051 Inlined_Bodies
.Release
;
4056 --------------------------------
4057 -- Remove_Aspects_And_Pragmas --
4058 --------------------------------
4060 procedure Remove_Aspects_And_Pragmas
(Body_Decl
: Node_Id
) is
4061 procedure Remove_Items
(List
: List_Id
);
4062 -- Remove all useless aspects/pragmas from a particular list
4068 procedure Remove_Items
(List
: List_Id
) is
4071 Next_Item
: Node_Id
;
4074 -- Traverse the list looking for an aspect specification or a pragma
4076 Item
:= First
(List
);
4077 while Present
(Item
) loop
4078 Next_Item
:= Next
(Item
);
4080 if Nkind
(Item
) = N_Aspect_Specification
then
4081 Item_Id
:= Identifier
(Item
);
4082 elsif Nkind
(Item
) = N_Pragma
then
4083 Item_Id
:= Pragma_Identifier
(Item
);
4088 if Present
(Item_Id
)
4089 and then Nam_In
(Chars
(Item_Id
), Name_Contract_Cases
,
4094 Name_Refined_Global
,
4095 Name_Refined_Depends
,
4108 -- Start of processing for Remove_Aspects_And_Pragmas
4111 Remove_Items
(Aspect_Specifications
(Body_Decl
));
4112 Remove_Items
(Declarations
(Body_Decl
));
4113 end Remove_Aspects_And_Pragmas
;
4115 --------------------------
4116 -- Remove_Dead_Instance --
4117 --------------------------
4119 procedure Remove_Dead_Instance
(N
: Node_Id
) is
4124 while J
<= Pending_Instantiations
.Last
loop
4125 if Pending_Instantiations
.Table
(J
).Inst_Node
= N
then
4126 Pending_Instantiations
.Table
(J
).Inst_Node
:= Empty
;
4132 end Remove_Dead_Instance
;