1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2007, 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 2, 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 COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Debug; use Debug;
30 with Einfo; use Einfo;
31 with Errout; use Errout;
32 with Elists; use Elists;
33 with Exp_Atag; use Exp_Atag;
34 with Exp_Ch2; use Exp_Ch2;
35 with Exp_Ch3; use Exp_Ch3;
36 with Exp_Ch7; use Exp_Ch7;
37 with Exp_Ch9; use Exp_Ch9;
38 with Exp_Dbug; use Exp_Dbug;
39 with Exp_Disp; use Exp_Disp;
40 with Exp_Dist; use Exp_Dist;
41 with Exp_Intr; use Exp_Intr;
42 with Exp_Pakd; use Exp_Pakd;
43 with Exp_Tss; use Exp_Tss;
44 with Exp_Util; use Exp_Util;
45 with Fname; use Fname;
46 with Freeze; use Freeze;
47 with Inline; use Inline;
49 with Namet; use Namet;
50 with Nlists; use Nlists;
51 with Nmake; use Nmake;
53 with Restrict; use Restrict;
54 with Rident; use Rident;
55 with Rtsfind; use Rtsfind;
57 with Sem_Ch6; use Sem_Ch6;
58 with Sem_Ch8; use Sem_Ch8;
59 with Sem_Ch12; use Sem_Ch12;
60 with Sem_Ch13; use Sem_Ch13;
61 with Sem_Eval; use Sem_Eval;
62 with Sem_Disp; use Sem_Disp;
63 with Sem_Dist; use Sem_Dist;
64 with Sem_Mech; use Sem_Mech;
65 with Sem_Res; use Sem_Res;
66 with Sem_Util; use Sem_Util;
67 with Sinfo; use Sinfo;
68 with Snames; use Snames;
69 with Stand; use Stand;
70 with Targparm; use Targparm;
71 with Tbuild; use Tbuild;
72 with Uintp; use Uintp;
73 with Validsw; use Validsw;
75 package body Exp_Ch6 is
77 -----------------------
78 -- Local Subprograms --
79 -----------------------
81 procedure Add_Access_Actual_To_Build_In_Place_Call
82 (Function_Call : Node_Id;
83 Function_Id : Entity_Id;
84 Return_Object : Node_Id;
85 Is_Access : Boolean := False);
86 -- Ada 2005 (AI-318-02): Apply the Unrestricted_Access attribute to the
87 -- object name given by Return_Object and add the attribute to the end of
88 -- the actual parameter list associated with the build-in-place function
89 -- call denoted by Function_Call. However, if Is_Access is True, then
90 -- Return_Object is already an access expression, in which case it's passed
91 -- along directly to the build-in-place function. Finally, if Return_Object
92 -- is empty, then pass a null literal as the actual.
94 procedure Add_Alloc_Form_Actual_To_Build_In_Place_Call
95 (Function_Call : Node_Id;
96 Function_Id : Entity_Id;
97 Alloc_Form : BIP_Allocation_Form := Unspecified;
98 Alloc_Form_Exp : Node_Id := Empty);
99 -- Ada 2005 (AI-318-02): Add an actual indicating the form of allocation,
100 -- if any, to be done by a build-in-place function. If Alloc_Form_Exp is
101 -- present, then use it, otherwise pass a literal corresponding to the
102 -- Alloc_Form parameter (which must not be Unspecified in that case).
104 procedure Add_Extra_Actual_To_Call
105 (Subprogram_Call : Node_Id;
106 Extra_Formal : Entity_Id;
107 Extra_Actual : Node_Id);
108 -- Adds Extra_Actual as a named parameter association for the formal
109 -- Extra_Formal in Subprogram_Call.
111 procedure Add_Final_List_Actual_To_Build_In_Place_Call
112 (Function_Call : Node_Id;
113 Function_Id : Entity_Id;
114 Acc_Type : Entity_Id);
115 -- Ada 2005 (AI-318-02): For a build-in-place call, if the result type has
116 -- controlled parts, add an actual parameter that is a pointer to
117 -- appropriate finalization list. The finalization list is that of the
118 -- current scope, except for "new Acc'(F(...))" in which case it's the
119 -- finalization list of the access type returned by the allocator. Acc_Type
120 -- is that type in the allocator case; Empty otherwise.
122 procedure Add_Task_Actuals_To_Build_In_Place_Call
123 (Function_Call : Node_Id;
124 Function_Id : Entity_Id;
125 Master_Actual : Node_Id);
126 -- Ada 2005 (AI-318-02): For a build-in-place call, if the result type
127 -- contains tasks, add two actual parameters: the master, and a pointer to
128 -- the caller's activation chain. Master_Actual is the actual parameter
129 -- expression to pass for the master. In most cases, this is the current
130 -- master (_master). The two exceptions are: If the function call is the
131 -- initialization expression for an allocator, we pass the master of the
132 -- access type. If the function call is the initialization expression for
133 -- a return object, we pass along the master passed in by the caller. The
134 -- activation chain to pass is always the local one.
136 procedure Check_Overriding_Operation (Subp : Entity_Id);
137 -- Subp is a dispatching operation. Check whether it may override an
138 -- inherited private operation, in which case its DT entry is that of
139 -- the hidden operation, not the one it may have received earlier.
140 -- This must be done before emitting the code to set the corresponding
141 -- DT to the address of the subprogram. The actual placement of Subp in
142 -- the proper place in the list of primitive operations is done in
143 -- Declare_Inherited_Private_Subprograms, which also has to deal with
144 -- implicit operations. This duplication is unavoidable for now???
146 procedure Detect_Infinite_Recursion (N : Node_Id; Spec : Entity_Id);
147 -- This procedure is called only if the subprogram body N, whose spec
148 -- has the given entity Spec, contains a parameterless recursive call.
149 -- It attempts to generate runtime code to detect if this a case of
150 -- infinite recursion.
152 -- The body is scanned to determine dependencies. If the only external
153 -- dependencies are on a small set of scalar variables, then the values
154 -- of these variables are captured on entry to the subprogram, and if
155 -- the values are not changed for the call, we know immediately that
156 -- we have an infinite recursion.
158 procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id);
159 -- For each actual of an in-out or out parameter which is a numeric
160 -- (view) conversion of the form T (A), where A denotes a variable,
161 -- we insert the declaration:
163 -- Temp : T[ := T (A)];
165 -- prior to the call. Then we replace the actual with a reference to Temp,
166 -- and append the assignment:
168 -- A := TypeA (Temp);
170 -- after the call. Here TypeA is the actual type of variable A.
171 -- For out parameters, the initial declaration has no expression.
172 -- If A is not an entity name, we generate instead:
174 -- Var : TypeA renames A;
175 -- Temp : T := Var; -- omitting expression for out parameter.
177 -- Var := TypeA (Temp);
179 -- For other in-out parameters, we emit the required constraint checks
180 -- before and/or after the call.
182 -- For all parameter modes, actuals that denote components and slices
183 -- of packed arrays are expanded into suitable temporaries.
185 -- For non-scalar objects that are possibly unaligned, add call by copy
186 -- code (copy in for IN and IN OUT, copy out for OUT and IN OUT).
188 procedure Expand_Inlined_Call
191 Orig_Subp : Entity_Id);
192 -- If called subprogram can be inlined by the front-end, retrieve the
193 -- analyzed body, replace formals with actuals and expand call in place.
194 -- Generate thunks for actuals that are expressions, and insert the
195 -- corresponding constant declarations before the call. If the original
196 -- call is to a derived operation, the return type is the one of the
197 -- derived operation, but the body is that of the original, so return
198 -- expressions in the body must be converted to the desired type (which
199 -- is simply not noted in the tree without inline expansion).
201 function Expand_Protected_Object_Reference
203 Scop : Entity_Id) return Node_Id;
205 procedure Expand_Protected_Subprogram_Call
209 -- A call to a protected subprogram within the protected object may appear
210 -- as a regular call. The list of actuals must be expanded to contain a
211 -- reference to the object itself, and the call becomes a call to the
212 -- corresponding protected subprogram.
214 ----------------------------------------------
215 -- Add_Access_Actual_To_Build_In_Place_Call --
216 ----------------------------------------------
218 procedure Add_Access_Actual_To_Build_In_Place_Call
219 (Function_Call : Node_Id;
220 Function_Id : Entity_Id;
221 Return_Object : Node_Id;
222 Is_Access : Boolean := False)
224 Loc : constant Source_Ptr := Sloc (Function_Call);
225 Obj_Address : Node_Id;
226 Obj_Acc_Formal : Entity_Id;
229 -- Locate the implicit access parameter in the called function
231 Obj_Acc_Formal := Build_In_Place_Formal (Function_Id, BIP_Object_Access);
233 -- If no return object is provided, then pass null
235 if not Present (Return_Object) then
236 Obj_Address := Make_Null (Loc);
237 Set_Parent (Obj_Address, Function_Call);
239 -- If Return_Object is already an expression of an access type, then use
240 -- it directly, since it must be an access value denoting the return
241 -- object, and couldn't possibly be the return object itself.
244 Obj_Address := Return_Object;
245 Set_Parent (Obj_Address, Function_Call);
247 -- Apply Unrestricted_Access to caller's return object
251 Make_Attribute_Reference (Loc,
252 Prefix => Return_Object,
253 Attribute_Name => Name_Unrestricted_Access);
255 Set_Parent (Return_Object, Obj_Address);
256 Set_Parent (Obj_Address, Function_Call);
259 Analyze_And_Resolve (Obj_Address, Etype (Obj_Acc_Formal));
261 -- Build the parameter association for the new actual and add it to the
262 -- end of the function's actuals.
264 Add_Extra_Actual_To_Call (Function_Call, Obj_Acc_Formal, Obj_Address);
265 end Add_Access_Actual_To_Build_In_Place_Call;
267 --------------------------------------------------
268 -- Add_Alloc_Form_Actual_To_Build_In_Place_Call --
269 --------------------------------------------------
271 procedure Add_Alloc_Form_Actual_To_Build_In_Place_Call
272 (Function_Call : Node_Id;
273 Function_Id : Entity_Id;
274 Alloc_Form : BIP_Allocation_Form := Unspecified;
275 Alloc_Form_Exp : Node_Id := Empty)
277 Loc : constant Source_Ptr := Sloc (Function_Call);
278 Alloc_Form_Actual : Node_Id;
279 Alloc_Form_Formal : Node_Id;
282 -- The allocation form generally doesn't need to be passed in the case
283 -- of a constrained result subtype, since normally the caller performs
284 -- the allocation in that case. However this formal is still needed in
285 -- the case where the function has a tagged result, because generally
286 -- such functions can be called in a dispatching context and such calls
287 -- must be handled like calls to class-wide functions.
289 if Is_Constrained (Underlying_Type (Etype (Function_Id)))
290 and then not Is_Tagged_Type (Underlying_Type (Etype (Function_Id)))
295 -- Locate the implicit allocation form parameter in the called function.
296 -- Maybe it would be better for each implicit formal of a build-in-place
297 -- function to have a flag or a Uint attribute to identify it. ???
299 Alloc_Form_Formal := Build_In_Place_Formal (Function_Id, BIP_Alloc_Form);
301 if Present (Alloc_Form_Exp) then
302 pragma Assert (Alloc_Form = Unspecified);
304 Alloc_Form_Actual := Alloc_Form_Exp;
307 pragma Assert (Alloc_Form /= Unspecified);
310 Make_Integer_Literal (Loc,
311 Intval => UI_From_Int (BIP_Allocation_Form'Pos (Alloc_Form)));
314 Analyze_And_Resolve (Alloc_Form_Actual, Etype (Alloc_Form_Formal));
316 -- Build the parameter association for the new actual and add it to the
317 -- end of the function's actuals.
319 Add_Extra_Actual_To_Call
320 (Function_Call, Alloc_Form_Formal, Alloc_Form_Actual);
321 end Add_Alloc_Form_Actual_To_Build_In_Place_Call;
323 ------------------------------
324 -- Add_Extra_Actual_To_Call --
325 ------------------------------
327 procedure Add_Extra_Actual_To_Call
328 (Subprogram_Call : Node_Id;
329 Extra_Formal : Entity_Id;
330 Extra_Actual : Node_Id)
332 Loc : constant Source_Ptr := Sloc (Subprogram_Call);
333 Param_Assoc : Node_Id;
337 Make_Parameter_Association (Loc,
338 Selector_Name => New_Occurrence_Of (Extra_Formal, Loc),
339 Explicit_Actual_Parameter => Extra_Actual);
341 Set_Parent (Param_Assoc, Subprogram_Call);
342 Set_Parent (Extra_Actual, Param_Assoc);
344 if Present (Parameter_Associations (Subprogram_Call)) then
345 if Nkind (Last (Parameter_Associations (Subprogram_Call))) =
346 N_Parameter_Association
349 -- Find last named actual, and append
354 L := First_Actual (Subprogram_Call);
355 while Present (L) loop
356 if No (Next_Actual (L)) then
357 Set_Next_Named_Actual (Parent (L), Extra_Actual);
365 Set_First_Named_Actual (Subprogram_Call, Extra_Actual);
368 Append (Param_Assoc, To => Parameter_Associations (Subprogram_Call));
371 Set_Parameter_Associations (Subprogram_Call, New_List (Param_Assoc));
372 Set_First_Named_Actual (Subprogram_Call, Extra_Actual);
374 end Add_Extra_Actual_To_Call;
376 --------------------------------------------------
377 -- Add_Final_List_Actual_To_Build_In_Place_Call --
378 --------------------------------------------------
380 procedure Add_Final_List_Actual_To_Build_In_Place_Call
381 (Function_Call : Node_Id;
382 Function_Id : Entity_Id;
383 Acc_Type : Entity_Id)
385 Loc : constant Source_Ptr := Sloc (Function_Call);
386 Final_List : Node_Id;
387 Final_List_Actual : Node_Id;
388 Final_List_Formal : Node_Id;
391 -- No such extra parameter is needed if there are no controlled parts.
392 -- The test for Controlled_Type accounts for class-wide results (which
393 -- potentially have controlled parts, even if the root type doesn't),
394 -- and the test for a tagged result type is needed because calls to
395 -- such a function can in general occur in dispatching contexts, which
396 -- must be treated the same as a call to class-wide functions. Both of
397 -- these situations require that a finalization list be passed.
399 if not Controlled_Type (Underlying_Type (Etype (Function_Id)))
400 and then not Is_Tagged_Type (Underlying_Type (Etype (Function_Id)))
405 -- Locate implicit finalization list parameter in the called function
407 Final_List_Formal := Build_In_Place_Formal (Function_Id, BIP_Final_List);
409 -- Create the actual which is a pointer to the appropriate finalization
410 -- list. Acc_Type is present if and only if this call is the
411 -- initialization of an allocator. Use the Current_Scope or the Acc_Type
414 if Present (Acc_Type)
415 and then (Ekind (Acc_Type) = E_Anonymous_Access_Type
417 Present (Associated_Final_Chain (Base_Type (Acc_Type))))
419 Final_List := Find_Final_List (Acc_Type);
421 Final_List := Find_Final_List (Current_Scope);
425 Make_Attribute_Reference (Loc,
426 Prefix => Final_List,
427 Attribute_Name => Name_Unrestricted_Access);
429 Analyze_And_Resolve (Final_List_Actual, Etype (Final_List_Formal));
431 -- Build the parameter association for the new actual and add it to the
432 -- end of the function's actuals.
434 Add_Extra_Actual_To_Call
435 (Function_Call, Final_List_Formal, Final_List_Actual);
436 end Add_Final_List_Actual_To_Build_In_Place_Call;
438 ---------------------------------------------
439 -- Add_Task_Actuals_To_Build_In_Place_Call --
440 ---------------------------------------------
442 procedure Add_Task_Actuals_To_Build_In_Place_Call
443 (Function_Call : Node_Id;
444 Function_Id : Entity_Id;
445 Master_Actual : Node_Id)
446 -- Note: Master_Actual can be Empty, but only if there are no tasks
448 Loc : constant Source_Ptr := Sloc (Function_Call);
451 -- No such extra parameters are needed if there are no tasks
453 if not Has_Task (Etype (Function_Id)) then
460 Master_Formal : Node_Id;
462 -- Locate implicit master parameter in the called function
464 Master_Formal := Build_In_Place_Formal (Function_Id, BIP_Master);
466 Analyze_And_Resolve (Master_Actual, Etype (Master_Formal));
468 -- Build the parameter association for the new actual and add it to
469 -- the end of the function's actuals.
471 Add_Extra_Actual_To_Call
472 (Function_Call, Master_Formal, Master_Actual);
475 -- The activation chain
478 Activation_Chain_Actual : Node_Id;
479 Activation_Chain_Formal : Node_Id;
481 -- Locate implicit activation chain parameter in the called function
483 Activation_Chain_Formal := Build_In_Place_Formal
484 (Function_Id, BIP_Activation_Chain);
486 -- Create the actual which is a pointer to the current activation
489 Activation_Chain_Actual :=
490 Make_Attribute_Reference (Loc,
491 Prefix => Make_Identifier (Loc, Name_uChain),
492 Attribute_Name => Name_Unrestricted_Access);
495 (Activation_Chain_Actual, Etype (Activation_Chain_Formal));
497 -- Build the parameter association for the new actual and add it to
498 -- the end of the function's actuals.
500 Add_Extra_Actual_To_Call
501 (Function_Call, Activation_Chain_Formal, Activation_Chain_Actual);
503 end Add_Task_Actuals_To_Build_In_Place_Call;
505 -----------------------
506 -- BIP_Formal_Suffix --
507 -----------------------
509 function BIP_Formal_Suffix (Kind : BIP_Formal_Kind) return String is
512 when BIP_Alloc_Form =>
514 when BIP_Final_List =>
515 return "BIPfinallist";
518 when BIP_Activation_Chain =>
519 return "BIPactivationchain";
520 when BIP_Object_Access =>
523 end BIP_Formal_Suffix;
525 ---------------------------
526 -- Build_In_Place_Formal --
527 ---------------------------
529 function Build_In_Place_Formal
531 Kind : BIP_Formal_Kind) return Entity_Id
533 Extra_Formal : Entity_Id := Extra_Formals (Func);
536 -- Maybe it would be better for each implicit formal of a build-in-place
537 -- function to have a flag or a Uint attribute to identify it. ???
540 pragma Assert (Present (Extra_Formal));
542 Chars (Extra_Formal) =
543 New_External_Name (Chars (Func), BIP_Formal_Suffix (Kind));
544 Next_Formal_With_Extras (Extra_Formal);
548 end Build_In_Place_Formal;
550 --------------------------------
551 -- Check_Overriding_Operation --
552 --------------------------------
554 procedure Check_Overriding_Operation (Subp : Entity_Id) is
555 Typ : constant Entity_Id := Find_Dispatching_Type (Subp);
556 Op_List : constant Elist_Id := Primitive_Operations (Typ);
562 if Is_Derived_Type (Typ)
563 and then not Is_Private_Type (Typ)
564 and then In_Open_Scopes (Scope (Etype (Typ)))
565 and then Typ = Base_Type (Typ)
567 -- Subp overrides an inherited private operation if there is an
568 -- inherited operation with a different name than Subp (see
569 -- Derive_Subprogram) whose Alias is a hidden subprogram with the
570 -- same name as Subp.
572 Op_Elmt := First_Elmt (Op_List);
573 while Present (Op_Elmt) loop
574 Prim_Op := Node (Op_Elmt);
575 Par_Op := Alias (Prim_Op);
578 and then not Comes_From_Source (Prim_Op)
579 and then Chars (Prim_Op) /= Chars (Par_Op)
580 and then Chars (Par_Op) = Chars (Subp)
581 and then Is_Hidden (Par_Op)
582 and then Type_Conformant (Prim_Op, Subp)
584 Set_DT_Position (Subp, DT_Position (Prim_Op));
590 end Check_Overriding_Operation;
592 -------------------------------
593 -- Detect_Infinite_Recursion --
594 -------------------------------
596 procedure Detect_Infinite_Recursion (N : Node_Id; Spec : Entity_Id) is
597 Loc : constant Source_Ptr := Sloc (N);
599 Var_List : constant Elist_Id := New_Elmt_List;
600 -- List of globals referenced by body of procedure
602 Call_List : constant Elist_Id := New_Elmt_List;
603 -- List of recursive calls in body of procedure
605 Shad_List : constant Elist_Id := New_Elmt_List;
606 -- List of entity id's for entities created to capture the value of
607 -- referenced globals on entry to the procedure.
609 Scop : constant Uint := Scope_Depth (Spec);
610 -- This is used to record the scope depth of the current procedure, so
611 -- that we can identify global references.
613 Max_Vars : constant := 4;
614 -- Do not test more than four global variables
616 Count_Vars : Natural := 0;
617 -- Count variables found so far
629 function Process (Nod : Node_Id) return Traverse_Result;
630 -- Function to traverse the subprogram body (using Traverse_Func)
636 function Process (Nod : Node_Id) return Traverse_Result is
640 if Nkind (Nod) = N_Procedure_Call_Statement then
642 -- Case of one of the detected recursive calls
644 if Is_Entity_Name (Name (Nod))
645 and then Has_Recursive_Call (Entity (Name (Nod)))
646 and then Entity (Name (Nod)) = Spec
648 Append_Elmt (Nod, Call_List);
651 -- Any other procedure call may have side effects
657 -- A call to a pure function can always be ignored
659 elsif Nkind (Nod) = N_Function_Call
660 and then Is_Entity_Name (Name (Nod))
661 and then Is_Pure (Entity (Name (Nod)))
665 -- Case of an identifier reference
667 elsif Nkind (Nod) = N_Identifier then
670 -- If no entity, then ignore the reference
672 -- Not clear why this can happen. To investigate, remove this
673 -- test and look at the crash that occurs here in 3401-004 ???
678 -- Ignore entities with no Scope, again not clear how this
679 -- can happen, to investigate, look at 4108-008 ???
681 elsif No (Scope (Ent)) then
684 -- Ignore the reference if not to a more global object
686 elsif Scope_Depth (Scope (Ent)) >= Scop then
689 -- References to types, exceptions and constants are always OK
692 or else Ekind (Ent) = E_Exception
693 or else Ekind (Ent) = E_Constant
697 -- If other than a non-volatile scalar variable, we have some
698 -- kind of global reference (e.g. to a function) that we cannot
699 -- deal with so we forget the attempt.
701 elsif Ekind (Ent) /= E_Variable
702 or else not Is_Scalar_Type (Etype (Ent))
703 or else Treat_As_Volatile (Ent)
707 -- Otherwise we have a reference to a global scalar
710 -- Loop through global entities already detected
712 Elm := First_Elmt (Var_List);
714 -- If not detected before, record this new global reference
717 Count_Vars := Count_Vars + 1;
719 if Count_Vars <= Max_Vars then
720 Append_Elmt (Entity (Nod), Var_List);
727 -- If recorded before, ignore
729 elsif Node (Elm) = Entity (Nod) then
732 -- Otherwise keep looking
742 -- For all other node kinds, recursively visit syntactic children
749 function Traverse_Body is new Traverse_Func (Process);
751 -- Start of processing for Detect_Infinite_Recursion
754 -- Do not attempt detection in No_Implicit_Conditional mode, since we
755 -- won't be able to generate the code to handle the recursion in any
758 if Restriction_Active (No_Implicit_Conditionals) then
762 -- Otherwise do traversal and quit if we get abandon signal
764 if Traverse_Body (N) = Abandon then
767 -- We must have a call, since Has_Recursive_Call was set. If not just
768 -- ignore (this is only an error check, so if we have a funny situation,
769 -- due to bugs or errors, we do not want to bomb!)
771 elsif Is_Empty_Elmt_List (Call_List) then
775 -- Here is the case where we detect recursion at compile time
777 -- Push our current scope for analyzing the declarations and code that
778 -- we will insert for the checking.
782 -- This loop builds temporary variables for each of the referenced
783 -- globals, so that at the end of the loop the list Shad_List contains
784 -- these temporaries in one-to-one correspondence with the elements in
788 Elm := First_Elmt (Var_List);
789 while Present (Elm) loop
792 Make_Defining_Identifier (Loc,
793 Chars => New_Internal_Name ('S'));
794 Append_Elmt (Ent, Shad_List);
796 -- Insert a declaration for this temporary at the start of the
797 -- declarations for the procedure. The temporaries are declared as
798 -- constant objects initialized to the current values of the
799 -- corresponding temporaries.
802 Make_Object_Declaration (Loc,
803 Defining_Identifier => Ent,
804 Object_Definition => New_Occurrence_Of (Etype (Var), Loc),
805 Constant_Present => True,
806 Expression => New_Occurrence_Of (Var, Loc));
809 Prepend (Decl, Declarations (N));
811 Insert_After (Last, Decl);
819 -- Loop through calls
821 Call := First_Elmt (Call_List);
822 while Present (Call) loop
824 -- Build a predicate expression of the form
827 -- and then global1 = temp1
828 -- and then global2 = temp2
831 -- This predicate determines if any of the global values
832 -- referenced by the procedure have changed since the
833 -- current call, if not an infinite recursion is assured.
835 Test := New_Occurrence_Of (Standard_True, Loc);
837 Elm1 := First_Elmt (Var_List);
838 Elm2 := First_Elmt (Shad_List);
839 while Present (Elm1) loop
845 Left_Opnd => New_Occurrence_Of (Node (Elm1), Loc),
846 Right_Opnd => New_Occurrence_Of (Node (Elm2), Loc)));
852 -- Now we replace the call with the sequence
854 -- if no-changes (see above) then
855 -- raise Storage_Error;
860 Rewrite (Node (Call),
861 Make_If_Statement (Loc,
863 Then_Statements => New_List (
864 Make_Raise_Storage_Error (Loc,
865 Reason => SE_Infinite_Recursion)),
867 Else_Statements => New_List (
868 Relocate_Node (Node (Call)))));
870 Analyze (Node (Call));
875 -- Remove temporary scope stack entry used for analysis
878 end Detect_Infinite_Recursion;
884 procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id) is
885 Loc : constant Source_Ptr := Sloc (N);
890 E_Formal : Entity_Id;
892 procedure Add_Call_By_Copy_Code;
893 -- For cases where the parameter must be passed by copy, this routine
894 -- generates a temporary variable into which the actual is copied and
895 -- then passes this as the parameter. For an OUT or IN OUT parameter,
896 -- an assignment is also generated to copy the result back. The call
897 -- also takes care of any constraint checks required for the type
898 -- conversion case (on both the way in and the way out).
900 procedure Add_Simple_Call_By_Copy_Code;
901 -- This is similar to the above, but is used in cases where we know
902 -- that all that is needed is to simply create a temporary and copy
903 -- the value in and out of the temporary.
905 procedure Check_Fortran_Logical;
906 -- A value of type Logical that is passed through a formal parameter
907 -- must be normalized because .TRUE. usually does not have the same
908 -- representation as True. We assume that .FALSE. = False = 0.
909 -- What about functions that return a logical type ???
911 function Is_Legal_Copy return Boolean;
912 -- Check that an actual can be copied before generating the temporary
913 -- to be used in the call. If the actual is of a by_reference type then
914 -- the program is illegal (this can only happen in the presence of
915 -- rep. clauses that force an incorrect alignment). If the formal is
916 -- a by_reference parameter imposed by a DEC pragma, emit a warning to
917 -- the effect that this might lead to unaligned arguments.
919 function Make_Var (Actual : Node_Id) return Entity_Id;
920 -- Returns an entity that refers to the given actual parameter,
921 -- Actual (not including any type conversion). If Actual is an
922 -- entity name, then this entity is returned unchanged, otherwise
923 -- a renaming is created to provide an entity for the actual.
925 procedure Reset_Packed_Prefix;
926 -- The expansion of a packed array component reference is delayed in
927 -- the context of a call. Now we need to complete the expansion, so we
928 -- unmark the analyzed bits in all prefixes.
930 ---------------------------
931 -- Add_Call_By_Copy_Code --
932 ---------------------------
934 procedure Add_Call_By_Copy_Code is
940 F_Typ : constant Entity_Id := Etype (Formal);
945 if not Is_Legal_Copy then
950 Make_Defining_Identifier (Loc,
951 Chars => New_Internal_Name ('T'));
953 -- Use formal type for temp, unless formal type is an unconstrained
954 -- array, in which case we don't have to worry about bounds checks,
955 -- and we use the actual type, since that has appropriate bounds.
957 if Is_Array_Type (F_Typ) and then not Is_Constrained (F_Typ) then
958 Indic := New_Occurrence_Of (Etype (Actual), Loc);
960 Indic := New_Occurrence_Of (Etype (Formal), Loc);
963 if Nkind (Actual) = N_Type_Conversion then
964 V_Typ := Etype (Expression (Actual));
966 -- If the formal is an (in-)out parameter, capture the name
967 -- of the variable in order to build the post-call assignment.
969 Var := Make_Var (Expression (Actual));
971 Crep := not Same_Representation
972 (F_Typ, Etype (Expression (Actual)));
975 V_Typ := Etype (Actual);
976 Var := Make_Var (Actual);
980 -- Setup initialization for case of in out parameter, or an out
981 -- parameter where the formal is an unconstrained array (in the
982 -- latter case, we have to pass in an object with bounds).
984 -- If this is an out parameter, the initial copy is wasteful, so as
985 -- an optimization for the one-dimensional case we extract the
986 -- bounds of the actual and build an uninitialized temporary of the
989 if Ekind (Formal) = E_In_Out_Parameter
990 or else (Is_Array_Type (F_Typ) and then not Is_Constrained (F_Typ))
992 if Nkind (Actual) = N_Type_Conversion then
993 if Conversion_OK (Actual) then
994 Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
996 Init := Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
999 elsif Ekind (Formal) = E_Out_Parameter
1000 and then Is_Array_Type (F_Typ)
1001 and then Number_Dimensions (F_Typ) = 1
1002 and then not Has_Non_Null_Base_Init_Proc (F_Typ)
1004 -- Actual is a one-dimensional array or slice, and the type
1005 -- requires no initialization. Create a temporary of the
1006 -- right size, but do not copy actual into it (optimization).
1010 Make_Subtype_Indication (Loc,
1012 New_Occurrence_Of (F_Typ, Loc),
1014 Make_Index_Or_Discriminant_Constraint (Loc,
1015 Constraints => New_List (
1018 Make_Attribute_Reference (Loc,
1019 Prefix => New_Occurrence_Of (Var, Loc),
1020 Attribute_name => Name_First),
1022 Make_Attribute_Reference (Loc,
1023 Prefix => New_Occurrence_Of (Var, Loc),
1024 Attribute_Name => Name_Last)))));
1027 Init := New_Occurrence_Of (Var, Loc);
1030 -- An initialization is created for packed conversions as
1031 -- actuals for out parameters to enable Make_Object_Declaration
1032 -- to determine the proper subtype for N_Node. Note that this
1033 -- is wasteful because the extra copying on the call side is
1034 -- not required for such out parameters. ???
1036 elsif Ekind (Formal) = E_Out_Parameter
1037 and then Nkind (Actual) = N_Type_Conversion
1038 and then (Is_Bit_Packed_Array (F_Typ)
1040 Is_Bit_Packed_Array (Etype (Expression (Actual))))
1042 if Conversion_OK (Actual) then
1043 Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
1045 Init := Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
1048 elsif Ekind (Formal) = E_In_Parameter then
1050 -- Handle the case in which the actual is a type conversion
1052 if Nkind (Actual) = N_Type_Conversion then
1053 if Conversion_OK (Actual) then
1054 Init := OK_Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
1056 Init := Convert_To (F_Typ, New_Occurrence_Of (Var, Loc));
1059 Init := New_Occurrence_Of (Var, Loc);
1067 Make_Object_Declaration (Loc,
1068 Defining_Identifier => Temp,
1069 Object_Definition => Indic,
1070 Expression => Init);
1071 Set_Assignment_OK (N_Node);
1072 Insert_Action (N, N_Node);
1074 -- Now, normally the deal here is that we use the defining
1075 -- identifier created by that object declaration. There is
1076 -- one exception to this. In the change of representation case
1077 -- the above declaration will end up looking like:
1079 -- temp : type := identifier;
1081 -- And in this case we might as well use the identifier directly
1082 -- and eliminate the temporary. Note that the analysis of the
1083 -- declaration was not a waste of time in that case, since it is
1084 -- what generated the necessary change of representation code. If
1085 -- the change of representation introduced additional code, as in
1086 -- a fixed-integer conversion, the expression is not an identifier
1087 -- and must be kept.
1090 and then Present (Expression (N_Node))
1091 and then Is_Entity_Name (Expression (N_Node))
1093 Temp := Entity (Expression (N_Node));
1094 Rewrite (N_Node, Make_Null_Statement (Loc));
1097 -- For IN parameter, all we do is to replace the actual
1099 if Ekind (Formal) = E_In_Parameter then
1100 Rewrite (Actual, New_Reference_To (Temp, Loc));
1103 -- Processing for OUT or IN OUT parameter
1106 -- Kill current value indications for the temporary variable we
1107 -- created, since we just passed it as an OUT parameter.
1109 Kill_Current_Values (Temp);
1111 -- If type conversion, use reverse conversion on exit
1113 if Nkind (Actual) = N_Type_Conversion then
1114 if Conversion_OK (Actual) then
1115 Expr := OK_Convert_To (V_Typ, New_Occurrence_Of (Temp, Loc));
1117 Expr := Convert_To (V_Typ, New_Occurrence_Of (Temp, Loc));
1120 Expr := New_Occurrence_Of (Temp, Loc);
1123 Rewrite (Actual, New_Reference_To (Temp, Loc));
1126 -- If the actual is a conversion of a packed reference, it may
1127 -- already have been expanded by Remove_Side_Effects, and the
1128 -- resulting variable is a temporary which does not designate
1129 -- the proper out-parameter, which may not be addressable. In
1130 -- that case, generate an assignment to the original expression
1131 -- (before expansion of the packed reference) so that the proper
1132 -- expansion of assignment to a packed component can take place.
1139 if Is_Renaming_Of_Object (Var)
1140 and then Nkind (Renamed_Object (Var)) = N_Selected_Component
1141 and then Is_Entity_Name (Prefix (Renamed_Object (Var)))
1142 and then Nkind (Original_Node (Prefix (Renamed_Object (Var))))
1143 = N_Indexed_Component
1145 Has_Non_Standard_Rep (Etype (Prefix (Renamed_Object (Var))))
1147 Obj := Renamed_Object (Var);
1149 Make_Selected_Component (Loc,
1151 New_Copy_Tree (Original_Node (Prefix (Obj))),
1152 Selector_Name => New_Copy (Selector_Name (Obj)));
1153 Reset_Analyzed_Flags (Lhs);
1156 Lhs := New_Occurrence_Of (Var, Loc);
1159 Set_Assignment_OK (Lhs);
1161 Append_To (Post_Call,
1162 Make_Assignment_Statement (Loc,
1164 Expression => Expr));
1168 end Add_Call_By_Copy_Code;
1170 ----------------------------------
1171 -- Add_Simple_Call_By_Copy_Code --
1172 ----------------------------------
1174 procedure Add_Simple_Call_By_Copy_Code is
1182 F_Typ : constant Entity_Id := Etype (Formal);
1185 if not Is_Legal_Copy then
1189 -- Use formal type for temp, unless formal type is an unconstrained
1190 -- array, in which case we don't have to worry about bounds checks,
1191 -- and we use the actual type, since that has appropriate bounds.
1193 if Is_Array_Type (F_Typ) and then not Is_Constrained (F_Typ) then
1194 Indic := New_Occurrence_Of (Etype (Actual), Loc);
1196 Indic := New_Occurrence_Of (Etype (Formal), Loc);
1199 -- Prepare to generate code
1201 Reset_Packed_Prefix;
1204 Make_Defining_Identifier (Loc,
1205 Chars => New_Internal_Name ('T'));
1206 Incod := Relocate_Node (Actual);
1207 Outcod := New_Copy_Tree (Incod);
1209 -- Generate declaration of temporary variable, initializing it
1210 -- with the input parameter unless we have an OUT formal or
1211 -- this is an initialization call.
1213 -- If the formal is an out parameter with discriminants, the
1214 -- discriminants must be captured even if the rest of the object
1215 -- is in principle uninitialized, because the discriminants may
1216 -- be read by the called subprogram.
1218 if Ekind (Formal) = E_Out_Parameter then
1221 if Has_Discriminants (Etype (Formal)) then
1222 Indic := New_Occurrence_Of (Etype (Actual), Loc);
1225 elsif Inside_Init_Proc then
1227 -- Could use a comment here to match comment below ???
1229 if Nkind (Actual) /= N_Selected_Component
1231 not Has_Discriminant_Dependent_Constraint
1232 (Entity (Selector_Name (Actual)))
1236 -- Otherwise, keep the component in order to generate the proper
1237 -- actual subtype, that depends on enclosing discriminants.
1245 Make_Object_Declaration (Loc,
1246 Defining_Identifier => Temp,
1247 Object_Definition => Indic,
1248 Expression => Incod);
1253 -- If the call is to initialize a component of a composite type,
1254 -- and the component does not depend on discriminants, use the
1255 -- actual type of the component. This is required in case the
1256 -- component is constrained, because in general the formal of the
1257 -- initialization procedure will be unconstrained. Note that if
1258 -- the component being initialized is constrained by an enclosing
1259 -- discriminant, the presence of the initialization in the
1260 -- declaration will generate an expression for the actual subtype.
1262 Set_No_Initialization (Decl);
1263 Set_Object_Definition (Decl,
1264 New_Occurrence_Of (Etype (Actual), Loc));
1267 Insert_Action (N, Decl);
1269 -- The actual is simply a reference to the temporary
1271 Rewrite (Actual, New_Occurrence_Of (Temp, Loc));
1273 -- Generate copy out if OUT or IN OUT parameter
1275 if Ekind (Formal) /= E_In_Parameter then
1277 Rhs := New_Occurrence_Of (Temp, Loc);
1279 -- Deal with conversion
1281 if Nkind (Lhs) = N_Type_Conversion then
1282 Lhs := Expression (Lhs);
1283 Rhs := Convert_To (Etype (Actual), Rhs);
1286 Append_To (Post_Call,
1287 Make_Assignment_Statement (Loc,
1289 Expression => Rhs));
1290 Set_Assignment_OK (Name (Last (Post_Call)));
1292 end Add_Simple_Call_By_Copy_Code;
1294 ---------------------------
1295 -- Check_Fortran_Logical --
1296 ---------------------------
1298 procedure Check_Fortran_Logical is
1299 Logical : constant Entity_Id := Etype (Formal);
1302 -- Note: this is very incomplete, e.g. it does not handle arrays
1303 -- of logical values. This is really not the right approach at all???)
1306 if Convention (Subp) = Convention_Fortran
1307 and then Root_Type (Etype (Formal)) = Standard_Boolean
1308 and then Ekind (Formal) /= E_In_Parameter
1310 Var := Make_Var (Actual);
1311 Append_To (Post_Call,
1312 Make_Assignment_Statement (Loc,
1313 Name => New_Occurrence_Of (Var, Loc),
1315 Unchecked_Convert_To (
1318 Left_Opnd => New_Occurrence_Of (Var, Loc),
1320 Unchecked_Convert_To (
1322 New_Occurrence_Of (Standard_False, Loc))))));
1324 end Check_Fortran_Logical;
1330 function Is_Legal_Copy return Boolean is
1332 -- An attempt to copy a value of such a type can only occur if
1333 -- representation clauses give the actual a misaligned address.
1335 if Is_By_Reference_Type (Etype (Formal)) then
1337 ("misaligned actual cannot be passed by reference", Actual);
1340 -- For users of Starlet, we assume that the specification of by-
1341 -- reference mechanism is mandatory. This may lead to unaligned
1342 -- objects but at least for DEC legacy code it is known to work.
1343 -- The warning will alert users of this code that a problem may
1346 elsif Mechanism (Formal) = By_Reference
1347 and then Is_Valued_Procedure (Scope (Formal))
1350 ("by_reference actual may be misaligned?", Actual);
1362 function Make_Var (Actual : Node_Id) return Entity_Id is
1366 if Is_Entity_Name (Actual) then
1367 return Entity (Actual);
1371 Make_Defining_Identifier (Loc,
1372 Chars => New_Internal_Name ('T'));
1375 Make_Object_Renaming_Declaration (Loc,
1376 Defining_Identifier => Var,
1378 New_Occurrence_Of (Etype (Actual), Loc),
1379 Name => Relocate_Node (Actual));
1381 Insert_Action (N, N_Node);
1386 -------------------------
1387 -- Reset_Packed_Prefix --
1388 -------------------------
1390 procedure Reset_Packed_Prefix is
1391 Pfx : Node_Id := Actual;
1394 Set_Analyzed (Pfx, False);
1395 exit when Nkind (Pfx) /= N_Selected_Component
1396 and then Nkind (Pfx) /= N_Indexed_Component;
1397 Pfx := Prefix (Pfx);
1399 end Reset_Packed_Prefix;
1401 -- Start of processing for Expand_Actuals
1404 Post_Call := New_List;
1406 Formal := First_Formal (Subp);
1407 Actual := First_Actual (N);
1408 while Present (Formal) loop
1409 E_Formal := Etype (Formal);
1411 if Is_Scalar_Type (E_Formal)
1412 or else Nkind (Actual) = N_Slice
1414 Check_Fortran_Logical;
1418 elsif Ekind (Formal) /= E_Out_Parameter then
1420 -- The unusual case of the current instance of a protected type
1421 -- requires special handling. This can only occur in the context
1422 -- of a call within the body of a protected operation.
1424 if Is_Entity_Name (Actual)
1425 and then Ekind (Entity (Actual)) = E_Protected_Type
1426 and then In_Open_Scopes (Entity (Actual))
1428 if Scope (Subp) /= Entity (Actual) then
1429 Error_Msg_N ("operation outside protected type may not "
1430 & "call back its protected operations?", Actual);
1434 Expand_Protected_Object_Reference (N, Entity (Actual)));
1437 -- Ada 2005 (AI-318-02): If the actual parameter is a call to a
1438 -- build-in-place function, then a temporary return object needs
1439 -- to be created and access to it must be passed to the function.
1440 -- Currently we limit such functions to those with inherently
1441 -- limited result subtypes, but eventually we plan to expand the
1442 -- functions that are treated as build-in-place to include other
1443 -- composite result types.
1445 if Ada_Version >= Ada_05
1446 and then Is_Build_In_Place_Function_Call (Actual)
1448 Make_Build_In_Place_Call_In_Anonymous_Context (Actual);
1451 Apply_Constraint_Check (Actual, E_Formal);
1453 -- Out parameter case. No constraint checks on access type
1456 elsif Is_Access_Type (E_Formal) then
1461 elsif Has_Discriminants (Base_Type (E_Formal))
1462 or else Has_Non_Null_Base_Init_Proc (E_Formal)
1464 Apply_Constraint_Check (Actual, E_Formal);
1469 Apply_Constraint_Check (Actual, Base_Type (E_Formal));
1472 -- Processing for IN-OUT and OUT parameters
1474 if Ekind (Formal) /= E_In_Parameter then
1476 -- For type conversions of arrays, apply length/range checks
1478 if Is_Array_Type (E_Formal)
1479 and then Nkind (Actual) = N_Type_Conversion
1481 if Is_Constrained (E_Formal) then
1482 Apply_Length_Check (Expression (Actual), E_Formal);
1484 Apply_Range_Check (Expression (Actual), E_Formal);
1488 -- If argument is a type conversion for a type that is passed
1489 -- by copy, then we must pass the parameter by copy.
1491 if Nkind (Actual) = N_Type_Conversion
1493 (Is_Numeric_Type (E_Formal)
1494 or else Is_Access_Type (E_Formal)
1495 or else Is_Enumeration_Type (E_Formal)
1496 or else Is_Bit_Packed_Array (Etype (Formal))
1497 or else Is_Bit_Packed_Array (Etype (Expression (Actual)))
1499 -- Also pass by copy if change of representation
1501 or else not Same_Representation
1503 Etype (Expression (Actual))))
1505 Add_Call_By_Copy_Code;
1507 -- References to components of bit packed arrays are expanded
1508 -- at this point, rather than at the point of analysis of the
1509 -- actuals, to handle the expansion of the assignment to
1510 -- [in] out parameters.
1512 elsif Is_Ref_To_Bit_Packed_Array (Actual) then
1513 Add_Simple_Call_By_Copy_Code;
1515 -- If a non-scalar actual is possibly bit-aligned, we need a copy
1516 -- because the back-end cannot cope with such objects. In other
1517 -- cases where alignment forces a copy, the back-end generates
1518 -- it properly. It should not be generated unconditionally in the
1519 -- front-end because it does not know precisely the alignment
1520 -- requirements of the target, and makes too conservative an
1521 -- estimate, leading to superfluous copies or spurious errors
1522 -- on by-reference parameters.
1524 elsif Nkind (Actual) = N_Selected_Component
1526 Component_May_Be_Bit_Aligned (Entity (Selector_Name (Actual)))
1527 and then not Represented_As_Scalar (Etype (Formal))
1529 Add_Simple_Call_By_Copy_Code;
1531 -- References to slices of bit packed arrays are expanded
1533 elsif Is_Ref_To_Bit_Packed_Slice (Actual) then
1534 Add_Call_By_Copy_Code;
1536 -- References to possibly unaligned slices of arrays are expanded
1538 elsif Is_Possibly_Unaligned_Slice (Actual) then
1539 Add_Call_By_Copy_Code;
1541 -- Deal with access types where the actual subtype and the
1542 -- formal subtype are not the same, requiring a check.
1544 -- It is necessary to exclude tagged types because of "downward
1545 -- conversion" errors and a strange assertion error in namet
1546 -- from gnatf in bug 1215-001 ???
1548 elsif Is_Access_Type (E_Formal)
1549 and then not Same_Type (E_Formal, Etype (Actual))
1550 and then not Is_Tagged_Type (Designated_Type (E_Formal))
1552 Add_Call_By_Copy_Code;
1554 -- If the actual is not a scalar and is marked for volatile
1555 -- treatment, whereas the formal is not volatile, then pass
1556 -- by copy unless it is a by-reference type.
1558 elsif Is_Entity_Name (Actual)
1559 and then Treat_As_Volatile (Entity (Actual))
1560 and then not Is_By_Reference_Type (Etype (Actual))
1561 and then not Is_Scalar_Type (Etype (Entity (Actual)))
1562 and then not Treat_As_Volatile (E_Formal)
1564 Add_Call_By_Copy_Code;
1566 elsif Nkind (Actual) = N_Indexed_Component
1567 and then Is_Entity_Name (Prefix (Actual))
1568 and then Has_Volatile_Components (Entity (Prefix (Actual)))
1570 Add_Call_By_Copy_Code;
1573 -- Processing for IN parameters
1576 -- For IN parameters is in the packed array case, we expand an
1577 -- indexed component (the circuit in Exp_Ch4 deliberately left
1578 -- indexed components appearing as actuals untouched, so that
1579 -- the special processing above for the OUT and IN OUT cases
1580 -- could be performed. We could make the test in Exp_Ch4 more
1581 -- complex and have it detect the parameter mode, but it is
1582 -- easier simply to handle all cases here.)
1584 if Nkind (Actual) = N_Indexed_Component
1585 and then Is_Packed (Etype (Prefix (Actual)))
1587 Reset_Packed_Prefix;
1588 Expand_Packed_Element_Reference (Actual);
1590 -- If we have a reference to a bit packed array, we copy it,
1591 -- since the actual must be byte aligned.
1593 -- Is this really necessary in all cases???
1595 elsif Is_Ref_To_Bit_Packed_Array (Actual) then
1596 Add_Simple_Call_By_Copy_Code;
1598 -- If a non-scalar actual is possibly unaligned, we need a copy
1600 elsif Is_Possibly_Unaligned_Object (Actual)
1601 and then not Represented_As_Scalar (Etype (Formal))
1603 Add_Simple_Call_By_Copy_Code;
1605 -- Similarly, we have to expand slices of packed arrays here
1606 -- because the result must be byte aligned.
1608 elsif Is_Ref_To_Bit_Packed_Slice (Actual) then
1609 Add_Call_By_Copy_Code;
1611 -- Only processing remaining is to pass by copy if this is a
1612 -- reference to a possibly unaligned slice, since the caller
1613 -- expects an appropriately aligned argument.
1615 elsif Is_Possibly_Unaligned_Slice (Actual) then
1616 Add_Call_By_Copy_Code;
1620 Next_Formal (Formal);
1621 Next_Actual (Actual);
1624 -- Find right place to put post call stuff if it is present
1626 if not Is_Empty_List (Post_Call) then
1628 -- If call is not a list member, it must be the triggering statement
1629 -- of a triggering alternative or an entry call alternative, and we
1630 -- can add the post call stuff to the corresponding statement list.
1632 if not Is_List_Member (N) then
1634 P : constant Node_Id := Parent (N);
1637 pragma Assert (Nkind (P) = N_Triggering_Alternative
1638 or else Nkind (P) = N_Entry_Call_Alternative);
1640 if Is_Non_Empty_List (Statements (P)) then
1641 Insert_List_Before_And_Analyze
1642 (First (Statements (P)), Post_Call);
1644 Set_Statements (P, Post_Call);
1648 -- Otherwise, normal case where N is in a statement sequence,
1649 -- just put the post-call stuff after the call statement.
1652 Insert_Actions_After (N, Post_Call);
1656 -- The call node itself is re-analyzed in Expand_Call
1664 -- This procedure handles expansion of function calls and procedure call
1665 -- statements (i.e. it serves as the body for Expand_N_Function_Call and
1666 -- Expand_N_Procedure_Call_Statement. Processing for calls includes:
1668 -- Replace call to Raise_Exception by Raise_Exception always if possible
1669 -- Provide values of actuals for all formals in Extra_Formals list
1670 -- Replace "call" to enumeration literal function by literal itself
1671 -- Rewrite call to predefined operator as operator
1672 -- Replace actuals to in-out parameters that are numeric conversions,
1673 -- with explicit assignment to temporaries before and after the call.
1674 -- Remove optional actuals if First_Optional_Parameter specified.
1676 -- Note that the list of actuals has been filled with default expressions
1677 -- during semantic analysis of the call. Only the extra actuals required
1678 -- for the 'Constrained attribute and for accessibility checks are added
1681 procedure Expand_Call (N : Node_Id) is
1682 Loc : constant Source_Ptr := Sloc (N);
1683 Remote : constant Boolean := Is_Remote_Call (N);
1685 Orig_Subp : Entity_Id := Empty;
1686 Parent_Subp : Entity_Id;
1687 Parent_Formal : Entity_Id;
1690 Prev : Node_Id := Empty;
1692 Prev_Orig : Node_Id;
1693 -- Original node for an actual, which may have been rewritten. If the
1694 -- actual is a function call that has been transformed from a selected
1695 -- component, the original node is unanalyzed. Otherwise, it carries
1696 -- semantic information used to generate additional actuals.
1699 Extra_Actuals : List_Id := No_List;
1701 CW_Interface_Formals_Present : Boolean := False;
1703 procedure Add_Actual_Parameter (Insert_Param : Node_Id);
1704 -- Adds one entry to the end of the actual parameter list. Used for
1705 -- default parameters and for extra actuals (for Extra_Formals). The
1706 -- argument is an N_Parameter_Association node.
1708 procedure Add_Extra_Actual (Expr : Node_Id; EF : Entity_Id);
1709 -- Adds an extra actual to the list of extra actuals. Expr is the
1710 -- expression for the value of the actual, EF is the entity for the
1713 function Inherited_From_Formal (S : Entity_Id) return Entity_Id;
1714 -- Within an instance, a type derived from a non-tagged formal derived
1715 -- type inherits from the original parent, not from the actual. This is
1716 -- tested in 4723-003. The current derivation mechanism has the derived
1717 -- type inherit from the actual, which is only correct outside of the
1718 -- instance. If the subprogram is inherited, we test for this particular
1719 -- case through a convoluted tree traversal before setting the proper
1720 -- subprogram to be called.
1722 --------------------------
1723 -- Add_Actual_Parameter --
1724 --------------------------
1726 procedure Add_Actual_Parameter (Insert_Param : Node_Id) is
1727 Actual_Expr : constant Node_Id :=
1728 Explicit_Actual_Parameter (Insert_Param);
1731 -- Case of insertion is first named actual
1733 if No (Prev) or else
1734 Nkind (Parent (Prev)) /= N_Parameter_Association
1736 Set_Next_Named_Actual (Insert_Param, First_Named_Actual (N));
1737 Set_First_Named_Actual (N, Actual_Expr);
1740 if No (Parameter_Associations (N)) then
1741 Set_Parameter_Associations (N, New_List);
1742 Append (Insert_Param, Parameter_Associations (N));
1745 Insert_After (Prev, Insert_Param);
1748 -- Case of insertion is not first named actual
1751 Set_Next_Named_Actual
1752 (Insert_Param, Next_Named_Actual (Parent (Prev)));
1753 Set_Next_Named_Actual (Parent (Prev), Actual_Expr);
1754 Append (Insert_Param, Parameter_Associations (N));
1757 Prev := Actual_Expr;
1758 end Add_Actual_Parameter;
1760 ----------------------
1761 -- Add_Extra_Actual --
1762 ----------------------
1764 procedure Add_Extra_Actual (Expr : Node_Id; EF : Entity_Id) is
1765 Loc : constant Source_Ptr := Sloc (Expr);
1768 if Extra_Actuals = No_List then
1769 Extra_Actuals := New_List;
1770 Set_Parent (Extra_Actuals, N);
1773 Append_To (Extra_Actuals,
1774 Make_Parameter_Association (Loc,
1775 Explicit_Actual_Parameter => Expr,
1777 Make_Identifier (Loc, Chars (EF))));
1779 Analyze_And_Resolve (Expr, Etype (EF));
1780 end Add_Extra_Actual;
1782 ---------------------------
1783 -- Inherited_From_Formal --
1784 ---------------------------
1786 function Inherited_From_Formal (S : Entity_Id) return Entity_Id is
1788 Gen_Par : Entity_Id;
1789 Gen_Prim : Elist_Id;
1794 -- If the operation is inherited, it is attached to the corresponding
1795 -- type derivation. If the parent in the derivation is a generic
1796 -- actual, it is a subtype of the actual, and we have to recover the
1797 -- original derived type declaration to find the proper parent.
1799 if Nkind (Parent (S)) /= N_Full_Type_Declaration
1800 or else not Is_Derived_Type (Defining_Identifier (Parent (S)))
1801 or else Nkind (Type_Definition (Original_Node (Parent (S)))) /=
1802 N_Derived_Type_Definition
1803 or else not In_Instance
1810 (Type_Definition (Original_Node (Parent (S)))));
1812 if Nkind (Indic) = N_Subtype_Indication then
1813 Par := Entity (Subtype_Mark (Indic));
1815 Par := Entity (Indic);
1819 if not Is_Generic_Actual_Type (Par)
1820 or else Is_Tagged_Type (Par)
1821 or else Nkind (Parent (Par)) /= N_Subtype_Declaration
1822 or else not In_Open_Scopes (Scope (Par))
1827 Gen_Par := Generic_Parent_Type (Parent (Par));
1830 -- If the actual has no generic parent type, the formal is not
1831 -- a formal derived type, so nothing to inherit.
1833 if No (Gen_Par) then
1837 -- If the generic parent type is still the generic type, this is a
1838 -- private formal, not a derived formal, and there are no operations
1839 -- inherited from the formal.
1841 if Nkind (Parent (Gen_Par)) = N_Formal_Type_Declaration then
1845 Gen_Prim := Collect_Primitive_Operations (Gen_Par);
1847 Elmt := First_Elmt (Gen_Prim);
1848 while Present (Elmt) loop
1849 if Chars (Node (Elmt)) = Chars (S) then
1855 F1 := First_Formal (S);
1856 F2 := First_Formal (Node (Elmt));
1858 and then Present (F2)
1860 if Etype (F1) = Etype (F2)
1861 or else Etype (F2) = Gen_Par
1867 exit; -- not the right subprogram
1879 raise Program_Error;
1880 end Inherited_From_Formal;
1882 -- Start of processing for Expand_Call
1885 -- Ignore if previous error
1887 if Nkind (N) in N_Has_Etype and then Etype (N) = Any_Type then
1891 -- Call using access to subprogram with explicit dereference
1893 if Nkind (Name (N)) = N_Explicit_Dereference then
1894 Subp := Etype (Name (N));
1895 Parent_Subp := Empty;
1897 -- Case of call to simple entry, where the Name is a selected component
1898 -- whose prefix is the task, and whose selector name is the entry name
1900 elsif Nkind (Name (N)) = N_Selected_Component then
1901 Subp := Entity (Selector_Name (Name (N)));
1902 Parent_Subp := Empty;
1904 -- Case of call to member of entry family, where Name is an indexed
1905 -- component, with the prefix being a selected component giving the
1906 -- task and entry family name, and the index being the entry index.
1908 elsif Nkind (Name (N)) = N_Indexed_Component then
1909 Subp := Entity (Selector_Name (Prefix (Name (N))));
1910 Parent_Subp := Empty;
1915 Subp := Entity (Name (N));
1916 Parent_Subp := Alias (Subp);
1918 -- Replace call to Raise_Exception by call to Raise_Exception_Always
1919 -- if we can tell that the first parameter cannot possibly be null.
1920 -- This helps optimization and also generation of warnings.
1922 -- We do not do this if Raise_Exception_Always does not exist, which
1923 -- can happen in configurable run time profiles which provide only a
1924 -- Raise_Exception, which is in fact an unconditional raise anyway.
1926 if Is_RTE (Subp, RE_Raise_Exception)
1927 and then RTE_Available (RE_Raise_Exception_Always)
1930 FA : constant Node_Id := Original_Node (First_Actual (N));
1933 -- The case we catch is where the first argument is obtained
1934 -- using the Identity attribute (which must always be
1937 if Nkind (FA) = N_Attribute_Reference
1938 and then Attribute_Name (FA) = Name_Identity
1940 Subp := RTE (RE_Raise_Exception_Always);
1941 Set_Name (N, New_Occurrence_Of (Subp, Loc));
1946 if Ekind (Subp) = E_Entry then
1947 Parent_Subp := Empty;
1951 -- Ada 2005 (AI-345): We have a procedure call as a triggering
1952 -- alternative in an asynchronous select or as an entry call in
1953 -- a conditional or timed select. Check whether the procedure call
1954 -- is a renaming of an entry and rewrite it as an entry call.
1956 if Ada_Version >= Ada_05
1957 and then Nkind (N) = N_Procedure_Call_Statement
1959 ((Nkind (Parent (N)) = N_Triggering_Alternative
1960 and then Triggering_Statement (Parent (N)) = N)
1962 (Nkind (Parent (N)) = N_Entry_Call_Alternative
1963 and then Entry_Call_Statement (Parent (N)) = N))
1967 Ren_Root : Entity_Id := Subp;
1970 -- This may be a chain of renamings, find the root
1972 if Present (Alias (Ren_Root)) then
1973 Ren_Root := Alias (Ren_Root);
1976 if Present (Original_Node (Parent (Parent (Ren_Root)))) then
1977 Ren_Decl := Original_Node (Parent (Parent (Ren_Root)));
1979 if Nkind (Ren_Decl) = N_Subprogram_Renaming_Declaration then
1981 Make_Entry_Call_Statement (Loc,
1983 New_Copy_Tree (Name (Ren_Decl)),
1984 Parameter_Associations =>
1985 New_Copy_List_Tree (Parameter_Associations (N))));
1993 -- First step, compute extra actuals, corresponding to any
1994 -- Extra_Formals present. Note that we do not access Extra_Formals
1995 -- directly, instead we simply note the presence of the extra
1996 -- formals as we process the regular formals and collect the
1997 -- corresponding actuals in Extra_Actuals.
1999 -- We also generate any required range checks for actuals as we go
2000 -- through the loop, since this is a convenient place to do this.
2002 Formal := First_Formal (Subp);
2003 Actual := First_Actual (N);
2004 while Present (Formal) loop
2006 -- Generate range check if required (not activated yet ???)
2008 -- if Do_Range_Check (Actual) then
2009 -- Set_Do_Range_Check (Actual, False);
2010 -- Generate_Range_Check
2011 -- (Actual, Etype (Formal), CE_Range_Check_Failed);
2014 -- Prepare to examine current entry
2017 Prev_Orig := Original_Node (Prev);
2019 -- The original actual may have been a call written in prefix
2020 -- form, and rewritten before analysis.
2022 if not Analyzed (Prev_Orig)
2024 (Nkind (Actual) = N_Function_Call
2026 Nkind (Actual) = N_Identifier)
2031 -- Ada 2005 (AI-251): Check if any formal is a class-wide interface
2032 -- to expand it in a further round.
2034 CW_Interface_Formals_Present :=
2035 CW_Interface_Formals_Present
2037 (Ekind (Etype (Formal)) = E_Class_Wide_Type
2038 and then Is_Interface (Etype (Etype (Formal))))
2040 (Ekind (Etype (Formal)) = E_Anonymous_Access_Type
2041 and then Is_Interface (Directly_Designated_Type
2042 (Etype (Etype (Formal)))));
2044 -- Create possible extra actual for constrained case. Usually, the
2045 -- extra actual is of the form actual'constrained, but since this
2046 -- attribute is only available for unconstrained records, TRUE is
2047 -- expanded if the type of the formal happens to be constrained (for
2048 -- instance when this procedure is inherited from an unconstrained
2049 -- record to a constrained one) or if the actual has no discriminant
2050 -- (its type is constrained). An exception to this is the case of a
2051 -- private type without discriminants. In this case we pass FALSE
2052 -- because the object has underlying discriminants with defaults.
2054 if Present (Extra_Constrained (Formal)) then
2055 if Ekind (Etype (Prev)) in Private_Kind
2056 and then not Has_Discriminants (Base_Type (Etype (Prev)))
2059 New_Occurrence_Of (Standard_False, Loc),
2060 Extra_Constrained (Formal));
2062 elsif Is_Constrained (Etype (Formal))
2063 or else not Has_Discriminants (Etype (Prev))
2066 New_Occurrence_Of (Standard_True, Loc),
2067 Extra_Constrained (Formal));
2069 -- Do not produce extra actuals for Unchecked_Union parameters.
2070 -- Jump directly to the end of the loop.
2072 elsif Is_Unchecked_Union (Base_Type (Etype (Actual))) then
2073 goto Skip_Extra_Actual_Generation;
2076 -- If the actual is a type conversion, then the constrained
2077 -- test applies to the actual, not the target type.
2083 -- Test for unchecked conversions as well, which can occur
2084 -- as out parameter actuals on calls to stream procedures.
2087 while Nkind (Act_Prev) = N_Type_Conversion
2088 or else Nkind (Act_Prev) = N_Unchecked_Type_Conversion
2090 Act_Prev := Expression (Act_Prev);
2093 -- If the expression is a conversion of a dereference,
2094 -- this is internally generated code that manipulates
2095 -- addresses, e.g. when building interface tables. No
2096 -- check should occur in this case, and the discriminated
2097 -- object is not directly a hand.
2099 if not Comes_From_Source (Actual)
2100 and then Nkind (Actual) = N_Unchecked_Type_Conversion
2101 and then Nkind (Act_Prev) = N_Explicit_Dereference
2104 (New_Occurrence_Of (Standard_False, Loc),
2105 Extra_Constrained (Formal));
2109 (Make_Attribute_Reference (Sloc (Prev),
2111 Duplicate_Subexpr_No_Checks
2112 (Act_Prev, Name_Req => True),
2113 Attribute_Name => Name_Constrained),
2114 Extra_Constrained (Formal));
2120 -- Create possible extra actual for accessibility level
2122 if Present (Extra_Accessibility (Formal)) then
2124 -- Ada 2005 (AI-252): If the actual was rewritten as an Access
2125 -- attribute, then the original actual may be an aliased object
2126 -- occurring as the prefix in a call using "Object.Operation"
2127 -- notation. In that case we must pass the level of the object,
2128 -- so Prev_Orig is reset to Prev and the attribute will be
2129 -- processed by the code for Access attributes further below.
2131 if Prev_Orig /= Prev
2132 and then Nkind (Prev) = N_Attribute_Reference
2134 Get_Attribute_Id (Attribute_Name (Prev)) = Attribute_Access
2135 and then Is_Aliased_View (Prev_Orig)
2140 if Is_Entity_Name (Prev_Orig) then
2142 -- When passing an access parameter, or a renaming of an access
2143 -- parameter, as the actual to another access parameter we need
2144 -- to pass along the actual's own access level parameter. This
2145 -- is done if we are within the scope of the formal access
2146 -- parameter (if this is an inlined body the extra formal is
2149 if (Is_Formal (Entity (Prev_Orig))
2151 (Present (Renamed_Object (Entity (Prev_Orig)))
2153 Is_Entity_Name (Renamed_Object (Entity (Prev_Orig)))
2156 (Entity (Renamed_Object (Entity (Prev_Orig))))))
2157 and then Ekind (Etype (Prev_Orig)) = E_Anonymous_Access_Type
2158 and then In_Open_Scopes (Scope (Entity (Prev_Orig)))
2161 Parm_Ent : constant Entity_Id := Param_Entity (Prev_Orig);
2164 pragma Assert (Present (Parm_Ent));
2166 if Present (Extra_Accessibility (Parm_Ent)) then
2169 (Extra_Accessibility (Parm_Ent), Loc),
2170 Extra_Accessibility (Formal));
2172 -- If the actual access parameter does not have an
2173 -- associated extra formal providing its scope level,
2174 -- then treat the actual as having library-level
2179 (Make_Integer_Literal (Loc,
2180 Intval => Scope_Depth (Standard_Standard)),
2181 Extra_Accessibility (Formal));
2185 -- The actual is a normal access value, so just pass the level
2186 -- of the actual's access type.
2190 (Make_Integer_Literal (Loc,
2191 Intval => Type_Access_Level (Etype (Prev_Orig))),
2192 Extra_Accessibility (Formal));
2196 case Nkind (Prev_Orig) is
2198 when N_Attribute_Reference =>
2200 case Get_Attribute_Id (Attribute_Name (Prev_Orig)) is
2202 -- For X'Access, pass on the level of the prefix X
2204 when Attribute_Access =>
2206 Make_Integer_Literal (Loc,
2208 Object_Access_Level (Prefix (Prev_Orig))),
2209 Extra_Accessibility (Formal));
2211 -- Treat the unchecked attributes as library-level
2213 when Attribute_Unchecked_Access |
2214 Attribute_Unrestricted_Access =>
2216 Make_Integer_Literal (Loc,
2217 Intval => Scope_Depth (Standard_Standard)),
2218 Extra_Accessibility (Formal));
2220 -- No other cases of attributes returning access
2221 -- values that can be passed to access parameters
2224 raise Program_Error;
2228 -- For allocators we pass the level of the execution of
2229 -- the called subprogram, which is one greater than the
2230 -- current scope level.
2234 Make_Integer_Literal (Loc,
2235 Scope_Depth (Current_Scope) + 1),
2236 Extra_Accessibility (Formal));
2238 -- For other cases we simply pass the level of the
2239 -- actual's access type.
2243 Make_Integer_Literal (Loc,
2244 Intval => Type_Access_Level (Etype (Prev_Orig))),
2245 Extra_Accessibility (Formal));
2251 -- Perform the check of 4.6(49) that prevents a null value from being
2252 -- passed as an actual to an access parameter. Note that the check is
2253 -- elided in the common cases of passing an access attribute or
2254 -- access parameter as an actual. Also, we currently don't enforce
2255 -- this check for expander-generated actuals and when -gnatdj is set.
2257 if Ada_Version >= Ada_05 then
2259 -- Ada 2005 (AI-231): Check null-excluding access types
2261 if Is_Access_Type (Etype (Formal))
2262 and then Can_Never_Be_Null (Etype (Formal))
2263 and then Nkind (Prev) /= N_Raise_Constraint_Error
2264 and then (Known_Null (Prev)
2265 or else not Can_Never_Be_Null (Etype (Prev)))
2267 Install_Null_Excluding_Check (Prev);
2270 -- Ada_Version < Ada_05
2273 if Ekind (Etype (Formal)) /= E_Anonymous_Access_Type
2274 or else Access_Checks_Suppressed (Subp)
2278 elsif Debug_Flag_J then
2281 elsif not Comes_From_Source (Prev) then
2284 elsif Is_Entity_Name (Prev)
2285 and then Ekind (Etype (Prev)) = E_Anonymous_Access_Type
2289 elsif Nkind (Prev) = N_Allocator
2290 or else Nkind (Prev) = N_Attribute_Reference
2294 -- Suppress null checks when passing to access parameters of Java
2295 -- and CIL subprograms. (Should this be done for other foreign
2296 -- conventions as well ???)
2298 elsif Convention (Subp) = Convention_Java
2299 or else Convention (Subp) = Convention_CIL
2304 Install_Null_Excluding_Check (Prev);
2308 -- Perform appropriate validity checks on parameters that
2311 if Validity_Checks_On then
2312 if (Ekind (Formal) = E_In_Parameter
2313 and then Validity_Check_In_Params)
2315 (Ekind (Formal) = E_In_Out_Parameter
2316 and then Validity_Check_In_Out_Params)
2318 -- If the actual is an indexed component of a packed type (or
2319 -- is an indexed or selected component whose prefix recursively
2320 -- meets this condition), it has not been expanded yet. It will
2321 -- be copied in the validity code that follows, and has to be
2322 -- expanded appropriately, so reanalyze it.
2324 -- What we do is just to unset analyzed bits on prefixes till
2325 -- we reach something that does not have a prefix.
2332 while Nkind (Nod) = N_Indexed_Component
2334 Nkind (Nod) = N_Selected_Component
2336 Set_Analyzed (Nod, False);
2337 Nod := Prefix (Nod);
2341 Ensure_Valid (Actual);
2345 -- For IN OUT and OUT parameters, ensure that subscripts are valid
2346 -- since this is a left side reference. We only do this for calls
2347 -- from the source program since we assume that compiler generated
2348 -- calls explicitly generate any required checks. We also need it
2349 -- only if we are doing standard validity checks, since clearly it
2350 -- is not needed if validity checks are off, and in subscript
2351 -- validity checking mode, all indexed components are checked with
2352 -- a call directly from Expand_N_Indexed_Component.
2354 if Comes_From_Source (N)
2355 and then Ekind (Formal) /= E_In_Parameter
2356 and then Validity_Checks_On
2357 and then Validity_Check_Default
2358 and then not Validity_Check_Subscripts
2360 Check_Valid_Lvalue_Subscripts (Actual);
2363 -- Mark any scalar OUT parameter that is a simple variable as no
2364 -- longer known to be valid (unless the type is always valid). This
2365 -- reflects the fact that if an OUT parameter is never set in a
2366 -- procedure, then it can become invalid on the procedure return.
2368 if Ekind (Formal) = E_Out_Parameter
2369 and then Is_Entity_Name (Actual)
2370 and then Ekind (Entity (Actual)) = E_Variable
2371 and then not Is_Known_Valid (Etype (Actual))
2373 Set_Is_Known_Valid (Entity (Actual), False);
2376 -- For an OUT or IN OUT parameter, if the actual is an entity, then
2377 -- clear current values, since they can be clobbered. We are probably
2378 -- doing this in more places than we need to, but better safe than
2379 -- sorry when it comes to retaining bad current values!
2381 if Ekind (Formal) /= E_In_Parameter
2382 and then Is_Entity_Name (Actual)
2384 Kill_Current_Values (Entity (Actual));
2387 -- If the formal is class wide and the actual is an aggregate, force
2388 -- evaluation so that the back end who does not know about class-wide
2389 -- type, does not generate a temporary of the wrong size.
2391 if not Is_Class_Wide_Type (Etype (Formal)) then
2394 elsif Nkind (Actual) = N_Aggregate
2395 or else (Nkind (Actual) = N_Qualified_Expression
2396 and then Nkind (Expression (Actual)) = N_Aggregate)
2398 Force_Evaluation (Actual);
2401 -- In a remote call, if the formal is of a class-wide type, check
2402 -- that the actual meets the requirements described in E.4(18).
2404 if Remote and then Is_Class_Wide_Type (Etype (Formal)) then
2405 Insert_Action (Actual,
2406 Make_Transportable_Check (Loc,
2407 Duplicate_Subexpr_Move_Checks (Actual)));
2410 -- This label is required when skipping extra actual generation for
2411 -- Unchecked_Union parameters.
2413 <<Skip_Extra_Actual_Generation>>
2415 Next_Actual (Actual);
2416 Next_Formal (Formal);
2419 -- If we are expanding a rhs of an assignment we need to check if tag
2420 -- propagation is needed. You might expect this processing to be in
2421 -- Analyze_Assignment but has to be done earlier (bottom-up) because the
2422 -- assignment might be transformed to a declaration for an unconstrained
2423 -- value if the expression is classwide.
2425 if Nkind (N) = N_Function_Call
2426 and then Is_Tag_Indeterminate (N)
2427 and then Is_Entity_Name (Name (N))
2430 Ass : Node_Id := Empty;
2433 if Nkind (Parent (N)) = N_Assignment_Statement then
2436 elsif Nkind (Parent (N)) = N_Qualified_Expression
2437 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
2439 Ass := Parent (Parent (N));
2441 elsif Nkind (Parent (N)) = N_Explicit_Dereference
2442 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
2444 Ass := Parent (Parent (N));
2448 and then Is_Class_Wide_Type (Etype (Name (Ass)))
2450 if Is_Access_Type (Etype (N)) then
2451 if Designated_Type (Etype (N)) /=
2452 Root_Type (Etype (Name (Ass)))
2455 ("tag-indeterminate expression "
2456 & " must have designated type& (RM 5.2 (6))",
2457 N, Root_Type (Etype (Name (Ass))));
2459 Propagate_Tag (Name (Ass), N);
2462 elsif Etype (N) /= Root_Type (Etype (Name (Ass))) then
2464 ("tag-indeterminate expression must have type&"
2465 & "(RM 5.2 (6))", N, Root_Type (Etype (Name (Ass))));
2468 Propagate_Tag (Name (Ass), N);
2471 -- The call will be rewritten as a dispatching call, and
2472 -- expanded as such.
2479 -- Ada 2005 (AI-251): If some formal is a class-wide interface, expand
2480 -- it to point to the correct secondary virtual table
2482 if (Nkind (N) = N_Function_Call
2483 or else Nkind (N) = N_Procedure_Call_Statement)
2484 and then CW_Interface_Formals_Present
2486 Expand_Interface_Actuals (N);
2489 -- Deals with Dispatch_Call if we still have a call, before expanding
2490 -- extra actuals since this will be done on the re-analysis of the
2491 -- dispatching call. Note that we do not try to shorten the actual
2492 -- list for a dispatching call, it would not make sense to do so.
2493 -- Expansion of dispatching calls is suppressed when VM_Target, because
2494 -- the VM back-ends directly handle the generation of dispatching
2495 -- calls and would have to undo any expansion to an indirect call.
2497 if (Nkind (N) = N_Function_Call
2498 or else Nkind (N) = N_Procedure_Call_Statement)
2499 and then Present (Controlling_Argument (N))
2500 and then VM_Target = No_VM
2502 Expand_Dispatching_Call (N);
2504 -- The following return is worrisome. Is it really OK to
2505 -- skip all remaining processing in this procedure ???
2509 -- Similarly, expand calls to RCI subprograms on which pragma
2510 -- All_Calls_Remote applies. The rewriting will be reanalyzed
2511 -- later. Do this only when the call comes from source since we do
2512 -- not want such a rewritting to occur in expanded code.
2514 elsif Is_All_Remote_Call (N) then
2515 Expand_All_Calls_Remote_Subprogram_Call (N);
2517 -- Similarly, do not add extra actuals for an entry call whose entity
2518 -- is a protected procedure, or for an internal protected subprogram
2519 -- call, because it will be rewritten as a protected subprogram call
2520 -- and reanalyzed (see Expand_Protected_Subprogram_Call).
2522 elsif Is_Protected_Type (Scope (Subp))
2523 and then (Ekind (Subp) = E_Procedure
2524 or else Ekind (Subp) = E_Function)
2528 -- During that loop we gathered the extra actuals (the ones that
2529 -- correspond to Extra_Formals), so now they can be appended.
2532 while Is_Non_Empty_List (Extra_Actuals) loop
2533 Add_Actual_Parameter (Remove_Head (Extra_Actuals));
2537 -- At this point we have all the actuals, so this is the point at
2538 -- which the various expansion activities for actuals is carried out.
2540 Expand_Actuals (N, Subp);
2542 -- If the subprogram is a renaming, or if it is inherited, replace it
2543 -- in the call with the name of the actual subprogram being called.
2544 -- If this is a dispatching call, the run-time decides what to call.
2545 -- The Alias attribute does not apply to entries.
2547 if Nkind (N) /= N_Entry_Call_Statement
2548 and then No (Controlling_Argument (N))
2549 and then Present (Parent_Subp)
2551 if Present (Inherited_From_Formal (Subp)) then
2552 Parent_Subp := Inherited_From_Formal (Subp);
2554 while Present (Alias (Parent_Subp)) loop
2555 Parent_Subp := Alias (Parent_Subp);
2559 -- The below setting of Entity is suspect, see F109-018 discussion???
2561 Set_Entity (Name (N), Parent_Subp);
2563 if Is_Abstract_Subprogram (Parent_Subp)
2564 and then not In_Instance
2567 ("cannot call abstract subprogram &!", Name (N), Parent_Subp);
2570 -- Add an explicit conversion for parameter of the derived type.
2571 -- This is only done for scalar and access in-parameters. Others
2572 -- have been expanded in expand_actuals.
2574 Formal := First_Formal (Subp);
2575 Parent_Formal := First_Formal (Parent_Subp);
2576 Actual := First_Actual (N);
2578 -- It is not clear that conversion is needed for intrinsic
2579 -- subprograms, but it certainly is for those that are user-
2580 -- defined, and that can be inherited on derivation, namely
2581 -- unchecked conversion and deallocation.
2582 -- General case needs study ???
2584 if not Is_Intrinsic_Subprogram (Parent_Subp)
2585 or else Is_Generic_Instance (Parent_Subp)
2587 while Present (Formal) loop
2588 if Etype (Formal) /= Etype (Parent_Formal)
2589 and then Is_Scalar_Type (Etype (Formal))
2590 and then Ekind (Formal) = E_In_Parameter
2592 not Subtypes_Statically_Match
2593 (Etype (Parent_Formal), Etype (Actual))
2594 and then not Raises_Constraint_Error (Actual)
2597 OK_Convert_To (Etype (Parent_Formal),
2598 Relocate_Node (Actual)));
2601 Resolve (Actual, Etype (Parent_Formal));
2602 Enable_Range_Check (Actual);
2604 elsif Is_Access_Type (Etype (Formal))
2605 and then Base_Type (Etype (Parent_Formal)) /=
2606 Base_Type (Etype (Actual))
2608 if Ekind (Formal) /= E_In_Parameter then
2610 Convert_To (Etype (Parent_Formal),
2611 Relocate_Node (Actual)));
2614 Resolve (Actual, Etype (Parent_Formal));
2617 Ekind (Etype (Parent_Formal)) = E_Anonymous_Access_Type
2618 and then Designated_Type (Etype (Parent_Formal))
2620 Designated_Type (Etype (Actual))
2621 and then not Is_Controlling_Formal (Formal)
2623 -- This unchecked conversion is not necessary unless
2624 -- inlining is enabled, because in that case the type
2625 -- mismatch may become visible in the body about to be
2629 Unchecked_Convert_To (Etype (Parent_Formal),
2630 Relocate_Node (Actual)));
2633 Resolve (Actual, Etype (Parent_Formal));
2637 Next_Formal (Formal);
2638 Next_Formal (Parent_Formal);
2639 Next_Actual (Actual);
2644 Subp := Parent_Subp;
2647 -- Check for violation of No_Abort_Statements
2649 if Is_RTE (Subp, RE_Abort_Task) then
2650 Check_Restriction (No_Abort_Statements, N);
2652 -- Check for violation of No_Dynamic_Attachment
2654 elsif RTU_Loaded (Ada_Interrupts)
2655 and then (Is_RTE (Subp, RE_Is_Reserved) or else
2656 Is_RTE (Subp, RE_Is_Attached) or else
2657 Is_RTE (Subp, RE_Current_Handler) or else
2658 Is_RTE (Subp, RE_Attach_Handler) or else
2659 Is_RTE (Subp, RE_Exchange_Handler) or else
2660 Is_RTE (Subp, RE_Detach_Handler) or else
2661 Is_RTE (Subp, RE_Reference))
2663 Check_Restriction (No_Dynamic_Attachment, N);
2666 -- Deal with case where call is an explicit dereference
2668 if Nkind (Name (N)) = N_Explicit_Dereference then
2670 -- Handle case of access to protected subprogram type
2672 if Is_Access_Protected_Subprogram_Type
2673 (Base_Type (Etype (Prefix (Name (N)))))
2675 -- If this is a call through an access to protected operation,
2676 -- the prefix has the form (object'address, operation'access).
2677 -- Rewrite as a for other protected calls: the object is the
2678 -- first parameter of the list of actuals.
2685 Ptr : constant Node_Id := Prefix (Name (N));
2687 T : constant Entity_Id :=
2688 Equivalent_Type (Base_Type (Etype (Ptr)));
2690 D_T : constant Entity_Id :=
2691 Designated_Type (Base_Type (Etype (Ptr)));
2695 Make_Selected_Component (Loc,
2696 Prefix => Unchecked_Convert_To (T, Ptr),
2698 New_Occurrence_Of (First_Entity (T), Loc));
2701 Make_Selected_Component (Loc,
2702 Prefix => Unchecked_Convert_To (T, Ptr),
2704 New_Occurrence_Of (Next_Entity (First_Entity (T)), Loc));
2707 Make_Explicit_Dereference (Loc,
2710 if Present (Parameter_Associations (N)) then
2711 Parm := Parameter_Associations (N);
2716 Prepend (Obj, Parm);
2718 if Etype (D_T) = Standard_Void_Type then
2720 Make_Procedure_Call_Statement (Loc,
2722 Parameter_Associations => Parm);
2725 Make_Function_Call (Loc,
2727 Parameter_Associations => Parm);
2730 Set_First_Named_Actual (Call, First_Named_Actual (N));
2731 Set_Etype (Call, Etype (D_T));
2733 -- We do not re-analyze the call to avoid infinite recursion.
2734 -- We analyze separately the prefix and the object, and set
2735 -- the checks on the prefix that would otherwise be emitted
2736 -- when resolving a call.
2740 Apply_Access_Check (Nam);
2747 -- If this is a call to an intrinsic subprogram, then perform the
2748 -- appropriate expansion to the corresponding tree node and we
2749 -- are all done (since after that the call is gone!)
2751 -- In the case where the intrinsic is to be processed by the back end,
2752 -- the call to Expand_Intrinsic_Call will do nothing, which is fine,
2753 -- since the idea in this case is to pass the call unchanged.
2754 -- If the intrinsic is an inherited unchecked conversion, and the
2755 -- derived type is the target type of the conversion, we must retain
2756 -- it as the return type of the expression. Otherwise the expansion
2757 -- below, which uses the parent operation, will yield the wrong type.
2759 if Is_Intrinsic_Subprogram (Subp) then
2760 Expand_Intrinsic_Call (N, Subp);
2762 if Nkind (N) = N_Unchecked_Type_Conversion
2763 and then Parent_Subp /= Orig_Subp
2764 and then Etype (Parent_Subp) /= Etype (Orig_Subp)
2766 Set_Etype (N, Etype (Orig_Subp));
2772 if Ekind (Subp) = E_Function
2773 or else Ekind (Subp) = E_Procedure
2775 if Is_Inlined (Subp) then
2777 Inlined_Subprogram : declare
2779 Must_Inline : Boolean := False;
2780 Spec : constant Node_Id := Unit_Declaration_Node (Subp);
2781 Scop : constant Entity_Id := Scope (Subp);
2783 function In_Unfrozen_Instance return Boolean;
2784 -- If the subprogram comes from an instance in the same
2785 -- unit, and the instance is not yet frozen, inlining might
2786 -- trigger order-of-elaboration problems in gigi.
2788 --------------------------
2789 -- In_Unfrozen_Instance --
2790 --------------------------
2792 function In_Unfrozen_Instance return Boolean is
2798 and then S /= Standard_Standard
2800 if Is_Generic_Instance (S)
2801 and then Present (Freeze_Node (S))
2802 and then not Analyzed (Freeze_Node (S))
2811 end In_Unfrozen_Instance;
2813 -- Start of processing for Inlined_Subprogram
2816 -- Verify that the body to inline has already been seen, and
2817 -- that if the body is in the current unit the inlining does
2818 -- not occur earlier. This avoids order-of-elaboration problems
2821 -- This should be documented in sinfo/einfo ???
2824 or else Nkind (Spec) /= N_Subprogram_Declaration
2825 or else No (Body_To_Inline (Spec))
2827 Must_Inline := False;
2829 -- If this an inherited function that returns a private
2830 -- type, do not inline if the full view is an unconstrained
2831 -- array, because such calls cannot be inlined.
2833 elsif Present (Orig_Subp)
2834 and then Is_Array_Type (Etype (Orig_Subp))
2835 and then not Is_Constrained (Etype (Orig_Subp))
2837 Must_Inline := False;
2839 elsif In_Unfrozen_Instance then
2840 Must_Inline := False;
2843 Bod := Body_To_Inline (Spec);
2845 if (In_Extended_Main_Code_Unit (N)
2846 or else In_Extended_Main_Code_Unit (Parent (N))
2847 or else Is_Always_Inlined (Subp))
2848 and then (not In_Same_Extended_Unit (Sloc (Bod), Loc)
2850 Earlier_In_Extended_Unit (Sloc (Bod), Loc))
2852 Must_Inline := True;
2854 -- If we are compiling a package body that is not the main
2855 -- unit, it must be for inlining/instantiation purposes,
2856 -- in which case we inline the call to insure that the same
2857 -- temporaries are generated when compiling the body by
2858 -- itself. Otherwise link errors can occur.
2860 -- If the function being called is itself in the main unit,
2861 -- we cannot inline, because there is a risk of double
2862 -- elaboration and/or circularity: the inlining can make
2863 -- visible a private entity in the body of the main unit,
2864 -- that gigi will see before its sees its proper definition.
2866 elsif not (In_Extended_Main_Code_Unit (N))
2867 and then In_Package_Body
2869 Must_Inline := not In_Extended_Main_Source_Unit (Subp);
2874 Expand_Inlined_Call (N, Subp, Orig_Subp);
2877 -- Let the back end handle it
2879 Add_Inlined_Body (Subp);
2881 if Front_End_Inlining
2882 and then Nkind (Spec) = N_Subprogram_Declaration
2883 and then (In_Extended_Main_Code_Unit (N))
2884 and then No (Body_To_Inline (Spec))
2885 and then not Has_Completion (Subp)
2886 and then In_Same_Extended_Unit (Sloc (Spec), Loc)
2889 ("cannot inline& (body not seen yet)?",
2893 end Inlined_Subprogram;
2897 -- Check for a protected subprogram. This is either an intra-object
2898 -- call, or a protected function call. Protected procedure calls are
2899 -- rewritten as entry calls and handled accordingly.
2901 -- In Ada 2005, this may be an indirect call to an access parameter
2902 -- that is an access_to_subprogram. In that case the anonymous type
2903 -- has a scope that is a protected operation, but the call is a
2906 Scop := Scope (Subp);
2908 if Nkind (N) /= N_Entry_Call_Statement
2909 and then Is_Protected_Type (Scop)
2910 and then Ekind (Subp) /= E_Subprogram_Type
2912 -- If the call is an internal one, it is rewritten as a call to
2913 -- to the corresponding unprotected subprogram.
2915 Expand_Protected_Subprogram_Call (N, Subp, Scop);
2918 -- Functions returning controlled objects need special attention
2919 -- If the return type is limited the context is an initialization
2920 -- and different processing applies.
2922 if Controlled_Type (Etype (Subp))
2923 and then not Is_Inherently_Limited_Type (Etype (Subp))
2924 and then not Is_Limited_Interface (Etype (Subp))
2926 Expand_Ctrl_Function_Call (N);
2929 -- Test for First_Optional_Parameter, and if so, truncate parameter
2930 -- list if there are optional parameters at the trailing end.
2931 -- Note we never delete procedures for call via a pointer.
2933 if (Ekind (Subp) = E_Procedure or else Ekind (Subp) = E_Function)
2934 and then Present (First_Optional_Parameter (Subp))
2937 Last_Keep_Arg : Node_Id;
2940 -- Last_Keep_Arg will hold the last actual that should be
2941 -- retained. If it remains empty at the end, it means that
2942 -- all parameters are optional.
2944 Last_Keep_Arg := Empty;
2946 -- Find first optional parameter, must be present since we
2947 -- checked the validity of the parameter before setting it.
2949 Formal := First_Formal (Subp);
2950 Actual := First_Actual (N);
2951 while Formal /= First_Optional_Parameter (Subp) loop
2952 Last_Keep_Arg := Actual;
2953 Next_Formal (Formal);
2954 Next_Actual (Actual);
2957 -- We have Formal and Actual pointing to the first potentially
2958 -- droppable argument. We can drop all the trailing arguments
2959 -- whose actual matches the default. Note that we know that all
2960 -- remaining formals have defaults, because we checked that this
2961 -- requirement was met before setting First_Optional_Parameter.
2963 -- We use Fully_Conformant_Expressions to check for identity
2964 -- between formals and actuals, which may miss some cases, but
2965 -- on the other hand, this is only an optimization (if we fail
2966 -- to truncate a parameter it does not affect functionality).
2967 -- So if the default is 3 and the actual is 1+2, we consider
2968 -- them unequal, which hardly seems worrisome.
2970 while Present (Formal) loop
2971 if not Fully_Conformant_Expressions
2972 (Actual, Default_Value (Formal))
2974 Last_Keep_Arg := Actual;
2977 Next_Formal (Formal);
2978 Next_Actual (Actual);
2981 -- If no arguments, delete entire list, this is the easy case
2983 if No (Last_Keep_Arg) then
2984 while Is_Non_Empty_List (Parameter_Associations (N)) loop
2985 Delete_Tree (Remove_Head (Parameter_Associations (N)));
2988 Set_Parameter_Associations (N, No_List);
2989 Set_First_Named_Actual (N, Empty);
2991 -- Case where at the last retained argument is positional. This
2992 -- is also an easy case, since the retained arguments are already
2993 -- in the right form, and we don't need to worry about the order
2994 -- of arguments that get eliminated.
2996 elsif Is_List_Member (Last_Keep_Arg) then
2997 while Present (Next (Last_Keep_Arg)) loop
2998 Delete_Tree (Remove_Next (Last_Keep_Arg));
3001 Set_First_Named_Actual (N, Empty);
3003 -- This is the annoying case where the last retained argument
3004 -- is a named parameter. Since the original arguments are not
3005 -- in declaration order, we may have to delete some fairly
3006 -- random collection of arguments.
3014 -- First step, remove all the named parameters from the
3015 -- list (they are still chained using First_Named_Actual
3016 -- and Next_Named_Actual, so we have not lost them!)
3018 Temp := First (Parameter_Associations (N));
3020 -- Case of all parameters named, remove them all
3022 if Nkind (Temp) = N_Parameter_Association then
3023 while Is_Non_Empty_List (Parameter_Associations (N)) loop
3024 Temp := Remove_Head (Parameter_Associations (N));
3027 -- Case of mixed positional/named, remove named parameters
3030 while Nkind (Next (Temp)) /= N_Parameter_Association loop
3034 while Present (Next (Temp)) loop
3035 Remove (Next (Temp));
3039 -- Now we loop through the named parameters, till we get
3040 -- to the last one to be retained, adding them to the list.
3041 -- Note that the Next_Named_Actual list does not need to be
3042 -- touched since we are only reordering them on the actual
3043 -- parameter association list.
3045 Passoc := Parent (First_Named_Actual (N));
3047 Temp := Relocate_Node (Passoc);
3049 (Parameter_Associations (N), Temp);
3051 Last_Keep_Arg = Explicit_Actual_Parameter (Passoc);
3052 Passoc := Parent (Next_Named_Actual (Passoc));
3055 Set_Next_Named_Actual (Temp, Empty);
3058 Temp := Next_Named_Actual (Passoc);
3059 exit when No (Temp);
3060 Set_Next_Named_Actual
3061 (Passoc, Next_Named_Actual (Parent (Temp)));
3069 -- Special processing for Ada 2005 AI-329, which requires a call to
3070 -- Raise_Exception to raise Constraint_Error if the Exception_Id is
3071 -- null. Note that we never need to do this in GNAT mode, or if the
3072 -- parameter to Raise_Exception is a use of Identity, since in these
3073 -- cases we know that the parameter is never null.
3075 -- Note: We must check that the node has not been inlined. This is
3076 -- required because under zfp the Raise_Exception subprogram has the
3077 -- pragma inline_always (and hence the call has been expanded above
3078 -- into a block containing the code of the subprogram).
3080 if Ada_Version >= Ada_05
3081 and then not GNAT_Mode
3082 and then Is_RTE (Subp, RE_Raise_Exception)
3083 and then Nkind (N) = N_Procedure_Call_Statement
3084 and then (Nkind (First_Actual (N)) /= N_Attribute_Reference
3085 or else Attribute_Name (First_Actual (N)) /= Name_Identity)
3088 RCE : constant Node_Id :=
3089 Make_Raise_Constraint_Error (Loc,
3090 Reason => CE_Null_Exception_Id);
3092 Insert_After (N, RCE);
3098 --------------------------
3099 -- Expand_Inlined_Call --
3100 --------------------------
3102 procedure Expand_Inlined_Call
3105 Orig_Subp : Entity_Id)
3107 Loc : constant Source_Ptr := Sloc (N);
3108 Is_Predef : constant Boolean :=
3109 Is_Predefined_File_Name
3110 (Unit_File_Name (Get_Source_Unit (Subp)));
3111 Orig_Bod : constant Node_Id :=
3112 Body_To_Inline (Unit_Declaration_Node (Subp));
3117 Decls : constant List_Id := New_List;
3118 Exit_Lab : Entity_Id := Empty;
3125 Ret_Type : Entity_Id;
3129 Temp_Typ : Entity_Id;
3131 Is_Unc : constant Boolean :=
3132 Is_Array_Type (Etype (Subp))
3133 and then not Is_Constrained (Etype (Subp));
3134 -- If the type returned by the function is unconstrained and the
3135 -- call can be inlined, special processing is required.
3137 function Is_Null_Procedure return Boolean;
3138 -- Predicate to recognize stubbed procedures and null procedures, for
3139 -- which there is no need for the full inlining mechanism.
3141 procedure Make_Exit_Label;
3142 -- Build declaration for exit label to be used in Return statements
3144 function Process_Formals (N : Node_Id) return Traverse_Result;
3145 -- Replace occurrence of a formal with the corresponding actual, or
3146 -- the thunk generated for it.
3148 function Process_Sloc (Nod : Node_Id) return Traverse_Result;
3149 -- If the call being expanded is that of an internal subprogram,
3150 -- set the sloc of the generated block to that of the call itself,
3151 -- so that the expansion is skipped by the -next- command in gdb.
3152 -- Same processing for a subprogram in a predefined file, e.g.
3153 -- Ada.Tags. If Debug_Generated_Code is true, suppress this change
3154 -- to simplify our own development.
3156 procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id);
3157 -- If the function body is a single expression, replace call with
3158 -- expression, else insert block appropriately.
3160 procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id);
3161 -- If procedure body has no local variables, inline body without
3162 -- creating block, otherwise rewrite call with block.
3164 function Formal_Is_Used_Once (Formal : Entity_Id) return Boolean;
3165 -- Determine whether a formal parameter is used only once in Orig_Bod
3167 -----------------------
3168 -- Is_Null_Procedure --
3169 -----------------------
3171 function Is_Null_Procedure return Boolean is
3172 Decl : constant Node_Id := Unit_Declaration_Node (Subp);
3175 if Ekind (Subp) /= E_Procedure then
3178 elsif Nkind (Orig_Bod) /= N_Subprogram_Body then
3181 -- Check if this is an Ada 2005 null procedure
3183 elsif Nkind (Decl) = N_Subprogram_Declaration
3184 and then Null_Present (Specification (Decl))
3188 -- Check if the body contains only a null statement, followed by the
3189 -- return statement added during expansion.
3193 Stat : constant Node_Id :=
3195 (Statements (Handled_Statement_Sequence (Orig_Bod)));
3197 Stat2 : constant Node_Id := Next (Stat);
3201 Nkind (Stat) = N_Null_Statement
3205 (Nkind (Stat2) = N_Simple_Return_Statement
3206 and then No (Next (Stat2))));
3209 end Is_Null_Procedure;
3211 ---------------------
3212 -- Make_Exit_Label --
3213 ---------------------
3215 procedure Make_Exit_Label is
3217 -- Create exit label for subprogram if one does not exist yet
3219 if No (Exit_Lab) then
3221 Make_Identifier (Loc,
3222 Chars => New_Internal_Name ('L'));
3224 Make_Defining_Identifier (Loc, Chars (Lab_Id)));
3225 Exit_Lab := Make_Label (Loc, Lab_Id);
3228 Make_Implicit_Label_Declaration (Loc,
3229 Defining_Identifier => Entity (Lab_Id),
3230 Label_Construct => Exit_Lab);
3232 end Make_Exit_Label;
3234 ---------------------
3235 -- Process_Formals --
3236 ---------------------
3238 function Process_Formals (N : Node_Id) return Traverse_Result is
3244 if Is_Entity_Name (N)
3245 and then Present (Entity (N))
3250 and then Scope (E) = Subp
3252 A := Renamed_Object (E);
3254 -- Rewrite the occurrence of the formal into an occurrence of
3255 -- the actual. Also establish visibility on the proper view of
3256 -- the actual's subtype for the body's context (if the actual's
3257 -- subtype is private at the call point but its full view is
3258 -- visible to the body, then the inlined tree here must be
3259 -- analyzed with the full view).
3261 if Is_Entity_Name (A) then
3262 Rewrite (N, New_Occurrence_Of (Entity (A), Loc));
3263 Check_Private_View (N);
3265 elsif Nkind (A) = N_Defining_Identifier then
3266 Rewrite (N, New_Occurrence_Of (A, Loc));
3267 Check_Private_View (N);
3272 Rewrite (N, New_Copy (A));
3278 elsif Nkind (N) = N_Simple_Return_Statement then
3279 if No (Expression (N)) then
3282 Make_Goto_Statement (Loc,
3283 Name => New_Copy (Lab_Id)));
3286 if Nkind (Parent (N)) = N_Handled_Sequence_Of_Statements
3287 and then Nkind (Parent (Parent (N))) = N_Subprogram_Body
3289 -- Function body is a single expression. No need for
3295 Num_Ret := Num_Ret + 1;
3299 -- Because of the presence of private types, the views of the
3300 -- expression and the context may be different, so place an
3301 -- unchecked conversion to the context type to avoid spurious
3302 -- errors, eg. when the expression is a numeric literal and
3303 -- the context is private. If the expression is an aggregate,
3304 -- use a qualified expression, because an aggregate is not a
3305 -- legal argument of a conversion.
3307 if Nkind (Expression (N)) = N_Aggregate
3308 or else Nkind (Expression (N)) = N_Null
3311 Make_Qualified_Expression (Sloc (N),
3312 Subtype_Mark => New_Occurrence_Of (Ret_Type, Sloc (N)),
3313 Expression => Relocate_Node (Expression (N)));
3316 Unchecked_Convert_To
3317 (Ret_Type, Relocate_Node (Expression (N)));
3320 if Nkind (Targ) = N_Defining_Identifier then
3322 Make_Assignment_Statement (Loc,
3323 Name => New_Occurrence_Of (Targ, Loc),
3324 Expression => Ret));
3327 Make_Assignment_Statement (Loc,
3328 Name => New_Copy (Targ),
3329 Expression => Ret));
3332 Set_Assignment_OK (Name (N));
3334 if Present (Exit_Lab) then
3336 Make_Goto_Statement (Loc,
3337 Name => New_Copy (Lab_Id)));
3343 -- Remove pragma Unreferenced since it may refer to formals that
3344 -- are not visible in the inlined body, and in any case we will
3345 -- not be posting warnings on the inlined body so it is unneeded.
3347 elsif Nkind (N) = N_Pragma
3348 and then Chars (N) = Name_Unreferenced
3350 Rewrite (N, Make_Null_Statement (Sloc (N)));
3356 end Process_Formals;
3358 procedure Replace_Formals is new Traverse_Proc (Process_Formals);
3364 function Process_Sloc (Nod : Node_Id) return Traverse_Result is
3366 if not Debug_Generated_Code then
3367 Set_Sloc (Nod, Sloc (N));
3368 Set_Comes_From_Source (Nod, False);
3374 procedure Reset_Slocs is new Traverse_Proc (Process_Sloc);
3376 ---------------------------
3377 -- Rewrite_Function_Call --
3378 ---------------------------
3380 procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id) is
3381 HSS : constant Node_Id := Handled_Statement_Sequence (Blk);
3382 Fst : constant Node_Id := First (Statements (HSS));
3385 -- Optimize simple case: function body is a single return statement,
3386 -- which has been expanded into an assignment.
3388 if Is_Empty_List (Declarations (Blk))
3389 and then Nkind (Fst) = N_Assignment_Statement
3390 and then No (Next (Fst))
3393 -- The function call may have been rewritten as the temporary
3394 -- that holds the result of the call, in which case remove the
3395 -- now useless declaration.
3397 if Nkind (N) = N_Identifier
3398 and then Nkind (Parent (Entity (N))) = N_Object_Declaration
3400 Rewrite (Parent (Entity (N)), Make_Null_Statement (Loc));
3403 Rewrite (N, Expression (Fst));
3405 elsif Nkind (N) = N_Identifier
3406 and then Nkind (Parent (Entity (N))) = N_Object_Declaration
3408 -- The block assigns the result of the call to the temporary
3410 Insert_After (Parent (Entity (N)), Blk);
3412 elsif Nkind (Parent (N)) = N_Assignment_Statement
3414 (Is_Entity_Name (Name (Parent (N)))
3416 (Nkind (Name (Parent (N))) = N_Explicit_Dereference
3417 and then Is_Entity_Name (Prefix (Name (Parent (N))))))
3419 -- Replace assignment with the block
3422 Original_Assignment : constant Node_Id := Parent (N);
3425 -- Preserve the original assignment node to keep the complete
3426 -- assignment subtree consistent enough for Analyze_Assignment
3427 -- to proceed (specifically, the original Lhs node must still
3428 -- have an assignment statement as its parent).
3430 -- We cannot rely on Original_Node to go back from the block
3431 -- node to the assignment node, because the assignment might
3432 -- already be a rewrite substitution.
3434 Discard_Node (Relocate_Node (Original_Assignment));
3435 Rewrite (Original_Assignment, Blk);
3438 elsif Nkind (Parent (N)) = N_Object_Declaration then
3439 Set_Expression (Parent (N), Empty);
3440 Insert_After (Parent (N), Blk);
3443 Insert_Before (Parent (N), Blk);
3445 end Rewrite_Function_Call;
3447 ----------------------------
3448 -- Rewrite_Procedure_Call --
3449 ----------------------------
3451 procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id) is
3452 HSS : constant Node_Id := Handled_Statement_Sequence (Blk);
3454 -- If there is a transient scope for N, this will be the scope of the
3455 -- actions for N, and the statements in Blk need to be within this
3456 -- scope. For example, they need to have visibility on the constant
3457 -- declarations created for the formals.
3459 -- If N needs no transient scope, and if there are no declarations in
3460 -- the inlined body, we can do a little optimization and insert the
3461 -- statements for the body directly after N, and rewrite N to a
3462 -- null statement, instead of rewriting N into a full-blown block
3465 if not Scope_Is_Transient
3466 and then Is_Empty_List (Declarations (Blk))
3468 Insert_List_After (N, Statements (HSS));
3469 Rewrite (N, Make_Null_Statement (Loc));
3473 end Rewrite_Procedure_Call;
3475 -------------------------
3476 -- Formal_Is_Used_Once --
3477 -------------------------
3479 function Formal_Is_Used_Once (Formal : Entity_Id) return Boolean is
3480 Use_Counter : Int := 0;
3482 function Count_Uses (N : Node_Id) return Traverse_Result;
3483 -- Traverse the tree and count the uses of the formal parameter.
3484 -- In this case, for optimization purposes, we do not need to
3485 -- continue the traversal once more than one use is encountered.
3491 function Count_Uses (N : Node_Id) return Traverse_Result is
3493 -- The original node is an identifier
3495 if Nkind (N) = N_Identifier
3496 and then Present (Entity (N))
3498 -- Original node's entity points to the one in the copied body
3500 and then Nkind (Entity (N)) = N_Identifier
3501 and then Present (Entity (Entity (N)))
3503 -- The entity of the copied node is the formal parameter
3505 and then Entity (Entity (N)) = Formal
3507 Use_Counter := Use_Counter + 1;
3509 if Use_Counter > 1 then
3511 -- Denote more than one use and abandon the traversal
3522 procedure Count_Formal_Uses is new Traverse_Proc (Count_Uses);
3524 -- Start of processing for Formal_Is_Used_Once
3527 Count_Formal_Uses (Orig_Bod);
3528 return Use_Counter = 1;
3529 end Formal_Is_Used_Once;
3531 -- Start of processing for Expand_Inlined_Call
3534 -- Check for special case of To_Address call, and if so, just do an
3535 -- unchecked conversion instead of expanding the call. Not only is this
3536 -- more efficient, but it also avoids problem with order of elaboration
3537 -- when address clauses are inlined (address expression elaborated at
3540 if Subp = RTE (RE_To_Address) then
3542 Unchecked_Convert_To
3544 Relocate_Node (First_Actual (N))));
3547 elsif Is_Null_Procedure then
3548 Rewrite (N, Make_Null_Statement (Loc));
3552 -- Check for an illegal attempt to inline a recursive procedure. If the
3553 -- subprogram has parameters this is detected when trying to supply a
3554 -- binding for parameters that already have one. For parameterless
3555 -- subprograms this must be done explicitly.
3557 if In_Open_Scopes (Subp) then
3558 Error_Msg_N ("call to recursive subprogram cannot be inlined?", N);
3559 Set_Is_Inlined (Subp, False);
3563 if Nkind (Orig_Bod) = N_Defining_Identifier
3564 or else Nkind (Orig_Bod) = N_Defining_Operator_Symbol
3566 -- Subprogram is a renaming_as_body. Calls appearing after the
3567 -- renaming can be replaced with calls to the renamed entity
3568 -- directly, because the subprograms are subtype conformant. If
3569 -- the renamed subprogram is an inherited operation, we must redo
3570 -- the expansion because implicit conversions may be needed.
3572 Set_Name (N, New_Occurrence_Of (Orig_Bod, Loc));
3574 if Present (Alias (Orig_Bod)) then
3581 -- Use generic machinery to copy body of inlined subprogram, as if it
3582 -- were an instantiation, resetting source locations appropriately, so
3583 -- that nested inlined calls appear in the main unit.
3585 Save_Env (Subp, Empty);
3586 Set_Copied_Sloc_For_Inlined_Body (N, Defining_Entity (Orig_Bod));
3588 Bod := Copy_Generic_Node (Orig_Bod, Empty, Instantiating => True);
3590 Make_Block_Statement (Loc,
3591 Declarations => Declarations (Bod),
3592 Handled_Statement_Sequence => Handled_Statement_Sequence (Bod));
3594 if No (Declarations (Bod)) then
3595 Set_Declarations (Blk, New_List);
3598 -- For the unconstrained case, capture the name of the local
3599 -- variable that holds the result. This must be the first declaration
3600 -- in the block, because its bounds cannot depend on local variables.
3601 -- Otherwise there is no way to declare the result outside of the
3602 -- block. Needless to say, in general the bounds will depend on the
3603 -- actuals in the call.
3606 Targ1 := Defining_Identifier (First (Declarations (Blk)));
3609 -- If this is a derived function, establish the proper return type
3611 if Present (Orig_Subp)
3612 and then Orig_Subp /= Subp
3614 Ret_Type := Etype (Orig_Subp);
3616 Ret_Type := Etype (Subp);
3619 -- Create temporaries for the actuals that are expressions, or that
3620 -- are scalars and require copying to preserve semantics.
3622 F := First_Formal (Subp);
3623 A := First_Actual (N);
3624 while Present (F) loop
3625 if Present (Renamed_Object (F)) then
3626 Error_Msg_N ("cannot inline call to recursive subprogram", N);
3630 -- If the argument may be a controlling argument in a call within
3631 -- the inlined body, we must preserve its classwide nature to insure
3632 -- that dynamic dispatching take place subsequently. If the formal
3633 -- has a constraint it must be preserved to retain the semantics of
3636 if Is_Class_Wide_Type (Etype (F))
3637 or else (Is_Access_Type (Etype (F))
3639 Is_Class_Wide_Type (Designated_Type (Etype (F))))
3641 Temp_Typ := Etype (F);
3643 elsif Base_Type (Etype (F)) = Base_Type (Etype (A))
3644 and then Etype (F) /= Base_Type (Etype (F))
3646 Temp_Typ := Etype (F);
3649 Temp_Typ := Etype (A);
3652 -- If the actual is a simple name or a literal, no need to
3653 -- create a temporary, object can be used directly.
3655 -- If the actual is a literal and the formal has its address taken,
3656 -- we cannot pass the literal itself as an argument, so its value
3657 -- must be captured in a temporary.
3659 if (Is_Entity_Name (A)
3661 (not Is_Scalar_Type (Etype (A))
3662 or else Ekind (Entity (A)) = E_Enumeration_Literal))
3664 -- When the actual is an identifier and the corresponding formal
3665 -- is used only once in the original body, the formal can be
3666 -- substituted directly with the actual parameter.
3668 or else (Nkind (A) = N_Identifier
3669 and then Formal_Is_Used_Once (F))
3672 ((Nkind (A) = N_Real_Literal or else
3673 Nkind (A) = N_Integer_Literal or else
3674 Nkind (A) = N_Character_Literal)
3675 and then not Address_Taken (F))
3677 if Etype (F) /= Etype (A) then
3679 (F, Unchecked_Convert_To (Etype (F), Relocate_Node (A)));
3681 Set_Renamed_Object (F, A);
3686 Make_Defining_Identifier (Loc,
3687 Chars => New_Internal_Name ('C'));
3689 -- If the actual for an in/in-out parameter is a view conversion,
3690 -- make it into an unchecked conversion, given that an untagged
3691 -- type conversion is not a proper object for a renaming.
3693 -- In-out conversions that involve real conversions have already
3694 -- been transformed in Expand_Actuals.
3696 if Nkind (A) = N_Type_Conversion
3697 and then Ekind (F) /= E_In_Parameter
3700 Make_Unchecked_Type_Conversion (Loc,
3701 Subtype_Mark => New_Occurrence_Of (Etype (F), Loc),
3702 Expression => Relocate_Node (Expression (A)));
3704 elsif Etype (F) /= Etype (A) then
3705 New_A := Unchecked_Convert_To (Etype (F), Relocate_Node (A));
3706 Temp_Typ := Etype (F);
3709 New_A := Relocate_Node (A);
3712 Set_Sloc (New_A, Sloc (N));
3714 -- If the actual has a by-reference type, it cannot be copied, so
3715 -- its value is captured in a renaming declaration. Otherwise
3716 -- declare a local constant initialized with the actual.
3718 if Ekind (F) = E_In_Parameter
3719 and then not Is_Limited_Type (Etype (A))
3720 and then not Is_Tagged_Type (Etype (A))
3723 Make_Object_Declaration (Loc,
3724 Defining_Identifier => Temp,
3725 Constant_Present => True,
3726 Object_Definition => New_Occurrence_Of (Temp_Typ, Loc),
3727 Expression => New_A);
3730 Make_Object_Renaming_Declaration (Loc,
3731 Defining_Identifier => Temp,
3732 Subtype_Mark => New_Occurrence_Of (Temp_Typ, Loc),
3736 Append (Decl, Decls);
3737 Set_Renamed_Object (F, Temp);
3744 -- Establish target of function call. If context is not assignment or
3745 -- declaration, create a temporary as a target. The declaration for
3746 -- the temporary may be subsequently optimized away if the body is a
3747 -- single expression, or if the left-hand side of the assignment is
3748 -- simple enough, i.e. an entity or an explicit dereference of one.
3750 if Ekind (Subp) = E_Function then
3751 if Nkind (Parent (N)) = N_Assignment_Statement
3752 and then Is_Entity_Name (Name (Parent (N)))
3754 Targ := Name (Parent (N));
3756 elsif Nkind (Parent (N)) = N_Assignment_Statement
3757 and then Nkind (Name (Parent (N))) = N_Explicit_Dereference
3758 and then Is_Entity_Name (Prefix (Name (Parent (N))))
3760 Targ := Name (Parent (N));
3763 -- Replace call with temporary and create its declaration
3766 Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
3767 Set_Is_Internal (Temp);
3769 -- For the unconstrained case. the generated temporary has the
3770 -- same constrained declaration as the result variable.
3771 -- It may eventually be possible to remove that temporary and
3772 -- use the result variable directly.
3776 Make_Object_Declaration (Loc,
3777 Defining_Identifier => Temp,
3778 Object_Definition =>
3779 New_Copy_Tree (Object_Definition (Parent (Targ1))));
3781 Replace_Formals (Decl);
3785 Make_Object_Declaration (Loc,
3786 Defining_Identifier => Temp,
3787 Object_Definition =>
3788 New_Occurrence_Of (Ret_Type, Loc));
3790 Set_Etype (Temp, Ret_Type);
3793 Set_No_Initialization (Decl);
3794 Append (Decl, Decls);
3795 Rewrite (N, New_Occurrence_Of (Temp, Loc));
3800 Insert_Actions (N, Decls);
3802 -- Traverse the tree and replace formals with actuals or their thunks.
3803 -- Attach block to tree before analysis and rewriting.
3805 Replace_Formals (Blk);
3806 Set_Parent (Blk, N);
3808 if not Comes_From_Source (Subp)
3814 if Present (Exit_Lab) then
3816 -- If the body was a single expression, the single return statement
3817 -- and the corresponding label are useless.
3821 Nkind (Last (Statements (Handled_Statement_Sequence (Blk)))) =
3824 Remove (Last (Statements (Handled_Statement_Sequence (Blk))));
3826 Append (Lab_Decl, (Declarations (Blk)));
3827 Append (Exit_Lab, Statements (Handled_Statement_Sequence (Blk)));
3831 -- Analyze Blk with In_Inlined_Body set, to avoid spurious errors on
3832 -- conflicting private views that Gigi would ignore. If this is
3833 -- predefined unit, analyze with checks off, as is done in the non-
3834 -- inlined run-time units.
3837 I_Flag : constant Boolean := In_Inlined_Body;
3840 In_Inlined_Body := True;
3844 Style : constant Boolean := Style_Check;
3846 Style_Check := False;
3847 Analyze (Blk, Suppress => All_Checks);
3848 Style_Check := Style;
3855 In_Inlined_Body := I_Flag;
3858 if Ekind (Subp) = E_Procedure then
3859 Rewrite_Procedure_Call (N, Blk);
3861 Rewrite_Function_Call (N, Blk);
3863 -- For the unconstrained case, the replacement of the call has been
3864 -- made prior to the complete analysis of the generated declarations.
3865 -- Propagate the proper type now.
3868 if Nkind (N) = N_Identifier then
3869 Set_Etype (N, Etype (Entity (N)));
3871 Set_Etype (N, Etype (Targ1));
3878 -- Cleanup mapping between formals and actuals for other expansions
3880 F := First_Formal (Subp);
3881 while Present (F) loop
3882 Set_Renamed_Object (F, Empty);
3885 end Expand_Inlined_Call;
3887 ----------------------------
3888 -- Expand_N_Function_Call --
3889 ----------------------------
3891 procedure Expand_N_Function_Call (N : Node_Id) is
3892 Typ : constant Entity_Id := Etype (N);
3894 function Returned_By_Reference return Boolean;
3895 -- If the return type is returned through the secondary stack; that is
3896 -- by reference, we don't want to create a temp to force stack checking.
3897 -- ???"sec stack" is not right -- Ada 95 return-by-reference object are
3898 -- returned wherever they are.
3899 -- Shouldn't this function be moved to exp_util???
3901 function Rhs_Of_Assign_Or_Decl (N : Node_Id) return Boolean;
3902 -- If the call is the right side of an assignment or the expression in
3903 -- an object declaration, we don't need to create a temp as the left
3904 -- side will already trigger stack checking if necessary.
3906 -- If the call is a component in an extension aggregate, it will be
3907 -- expanded into assignments as well, so no temporary is needed. This
3908 -- also solves the problem of functions returning types with unknown
3909 -- discriminants, where it is not possible to declare an object of the
3912 ---------------------------
3913 -- Returned_By_Reference --
3914 ---------------------------
3916 function Returned_By_Reference return Boolean is
3920 if Is_Inherently_Limited_Type (Typ) then
3923 elsif Nkind (Parent (N)) /= N_Simple_Return_Statement then
3926 elsif Requires_Transient_Scope (Typ) then
3928 -- Verify that the return type of the enclosing function has the
3929 -- same constrained status as that of the expression.
3932 while Ekind (S) /= E_Function loop
3936 return Is_Constrained (Typ) = Is_Constrained (Etype (S));
3940 end Returned_By_Reference;
3942 ---------------------------
3943 -- Rhs_Of_Assign_Or_Decl --
3944 ---------------------------
3946 function Rhs_Of_Assign_Or_Decl (N : Node_Id) return Boolean is
3948 if (Nkind (Parent (N)) = N_Assignment_Statement
3949 and then Expression (Parent (N)) = N)
3951 (Nkind (Parent (N)) = N_Qualified_Expression
3952 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
3953 and then Expression (Parent (Parent (N))) = Parent (N))
3955 (Nkind (Parent (N)) = N_Object_Declaration
3956 and then Expression (Parent (N)) = N)
3958 (Nkind (Parent (N)) = N_Component_Association
3959 and then Expression (Parent (N)) = N
3960 and then Nkind (Parent (Parent (N))) = N_Aggregate
3961 and then Rhs_Of_Assign_Or_Decl (Parent (Parent (N))))
3963 (Nkind (Parent (N)) = N_Extension_Aggregate
3964 and then Is_Private_Type (Etype (Typ)))
3970 end Rhs_Of_Assign_Or_Decl;
3972 -- Start of processing for Expand_N_Function_Call
3975 -- A special check. If stack checking is enabled, and the return type
3976 -- might generate a large temporary, and the call is not the right side
3977 -- of an assignment, then generate an explicit temporary. We do this
3978 -- because otherwise gigi may generate a large temporary on the fly and
3979 -- this can cause trouble with stack checking.
3981 -- This is unnecessary if the call is the expression in an object
3982 -- declaration, or if it appears outside of any library unit. This can
3983 -- only happen if it appears as an actual in a library-level instance,
3984 -- in which case a temporary will be generated for it once the instance
3985 -- itself is installed.
3987 if May_Generate_Large_Temp (Typ)
3988 and then not Rhs_Of_Assign_Or_Decl (N)
3989 and then not Returned_By_Reference
3990 and then Current_Scope /= Standard_Standard
3992 if Stack_Checking_Enabled then
3994 -- Note: it might be thought that it would be OK to use a call to
3995 -- Force_Evaluation here, but that's not good enough, because
3996 -- that can results in a 'Reference construct that may still need
4000 Loc : constant Source_Ptr := Sloc (N);
4001 Temp_Obj : constant Entity_Id :=
4002 Make_Defining_Identifier (Loc,
4003 Chars => New_Internal_Name ('F'));
4004 Temp_Typ : Entity_Id := Typ;
4011 if Is_Tagged_Type (Typ)
4012 and then Present (Controlling_Argument (N))
4014 if Nkind (Parent (N)) /= N_Procedure_Call_Statement
4015 and then Nkind (Parent (N)) /= N_Function_Call
4017 -- If this is a tag-indeterminate call, the object must
4020 if Is_Tag_Indeterminate (N) then
4021 Temp_Typ := Class_Wide_Type (Typ);
4025 -- If this is a dispatching call that is itself the
4026 -- controlling argument of an enclosing call, the
4027 -- nominal subtype of the object that replaces it must
4028 -- be classwide, so that dispatching will take place
4029 -- properly. If it is not a controlling argument, the
4030 -- object is not classwide.
4032 Proc := Entity (Name (Parent (N)));
4034 F := First_Formal (Proc);
4035 A := First_Actual (Parent (N));
4041 if Is_Controlling_Formal (F) then
4042 Temp_Typ := Class_Wide_Type (Typ);
4048 Make_Object_Declaration (Loc,
4049 Defining_Identifier => Temp_Obj,
4050 Object_Definition => New_Occurrence_Of (Temp_Typ, Loc),
4051 Constant_Present => True,
4052 Expression => Relocate_Node (N));
4053 Set_Assignment_OK (Decl);
4055 Insert_Actions (N, New_List (Decl));
4056 Rewrite (N, New_Occurrence_Of (Temp_Obj, Loc));
4060 -- If stack-checking is not enabled, increment serial number
4061 -- for internal names, so that subsequent symbols are consistent
4062 -- with and without stack-checking.
4064 Synchronize_Serial_Number;
4066 -- Now we can expand the call with consistent symbol names
4071 -- Normal case, expand the call
4076 end Expand_N_Function_Call;
4078 ---------------------------------------
4079 -- Expand_N_Procedure_Call_Statement --
4080 ---------------------------------------
4082 procedure Expand_N_Procedure_Call_Statement (N : Node_Id) is
4085 end Expand_N_Procedure_Call_Statement;
4087 ------------------------------
4088 -- Expand_N_Subprogram_Body --
4089 ------------------------------
4091 -- Add poll call if ATC polling is enabled, unless the body will be
4092 -- inlined by the back-end.
4094 -- Add dummy push/pop label nodes at start and end to clear any local
4095 -- exception indications if local-exception-to-goto optimization active.
4097 -- Add return statement if last statement in body is not a return statement
4098 -- (this makes things easier on Gigi which does not want to have to handle
4099 -- a missing return).
4101 -- Add call to Activate_Tasks if body is a task activator
4103 -- Deal with possible detection of infinite recursion
4105 -- Eliminate body completely if convention stubbed
4107 -- Encode entity names within body, since we will not need to reference
4108 -- these entities any longer in the front end.
4110 -- Initialize scalar out parameters if Initialize/Normalize_Scalars
4112 -- Reset Pure indication if any parameter has root type System.Address
4116 procedure Expand_N_Subprogram_Body (N : Node_Id) is
4117 Loc : constant Source_Ptr := Sloc (N);
4118 H : constant Node_Id := Handled_Statement_Sequence (N);
4119 Body_Id : Entity_Id;
4120 Spec_Id : Entity_Id;
4127 procedure Add_Return (S : List_Id);
4128 -- Append a return statement to the statement sequence S if the last
4129 -- statement is not already a return or a goto statement. Note that
4130 -- the latter test is not critical, it does not matter if we add a
4131 -- few extra returns, since they get eliminated anyway later on.
4137 procedure Add_Return (S : List_Id) is
4142 -- Get last statement, ignoring any Pop_xxx_Label nodes, which are
4143 -- not relevant in this context since they are not executable.
4145 Last_Stm := Last (S);
4146 while Nkind (Last_Stm) in N_Pop_xxx_Label loop
4150 -- Now insert return unless last statement is a transfer
4152 if not Is_Transfer (Last_Stm) then
4154 -- The source location for the return is the end label of the
4155 -- procedure if present. Otherwise use the sloc of the last
4156 -- statement in the list. If the list comes from a generated
4157 -- exception handler and we are not debugging generated code,
4158 -- all the statements within the handler are made invisible
4161 if Nkind (Parent (S)) = N_Exception_Handler
4162 and then not Comes_From_Source (Parent (S))
4164 Loc := Sloc (Last_Stm);
4166 elsif Present (End_Label (H)) then
4167 Loc := Sloc (End_Label (H));
4170 Loc := Sloc (Last_Stm);
4173 Append_To (S, Make_Simple_Return_Statement (Loc));
4177 -- Start of processing for Expand_N_Subprogram_Body
4180 -- Set L to either the list of declarations if present, or
4181 -- to the list of statements if no declarations are present.
4182 -- This is used to insert new stuff at the start.
4184 if Is_Non_Empty_List (Declarations (N)) then
4185 L := Declarations (N);
4187 L := Statements (H);
4190 -- If local-exception-to-goto optimization active, insert dummy push
4191 -- statements at start, and dummy pop statements at end.
4193 if (Debug_Flag_Dot_G
4194 or else Restriction_Active (No_Exception_Propagation))
4195 and then Is_Non_Empty_List (L)
4198 FS : constant Node_Id := First (L);
4199 FL : constant Source_Ptr := Sloc (FS);
4204 -- LS points to either last statement, if statements are present
4205 -- or to the last declaration if there are no statements present.
4206 -- It is the node after which the pop's are generated.
4208 if Is_Non_Empty_List (Statements (H)) then
4209 LS := Last (Statements (H));
4216 Insert_List_Before_And_Analyze (FS, New_List (
4217 Make_Push_Constraint_Error_Label (FL),
4218 Make_Push_Program_Error_Label (FL),
4219 Make_Push_Storage_Error_Label (FL)));
4221 Insert_List_After_And_Analyze (LS, New_List (
4222 Make_Pop_Constraint_Error_Label (LL),
4223 Make_Pop_Program_Error_Label (LL),
4224 Make_Pop_Storage_Error_Label (LL)));
4228 -- Find entity for subprogram
4230 Body_Id := Defining_Entity (N);
4232 if Present (Corresponding_Spec (N)) then
4233 Spec_Id := Corresponding_Spec (N);
4238 -- Need poll on entry to subprogram if polling enabled. We only do this
4239 -- for non-empty subprograms, since it does not seem necessary to poll
4240 -- for a dummy null subprogram. Do not add polling point if calls to
4241 -- this subprogram will be inlined by the back-end, to avoid repeated
4242 -- polling points in nested inlinings.
4244 if Is_Non_Empty_List (L) then
4245 if Is_Inlined (Spec_Id)
4246 and then Front_End_Inlining
4247 and then Optimization_Level > 1
4251 Generate_Poll_Call (First (L));
4255 -- If this is a Pure function which has any parameters whose root
4256 -- type is System.Address, reset the Pure indication, since it will
4257 -- likely cause incorrect code to be generated as the parameter is
4258 -- probably a pointer, and the fact that the same pointer is passed
4259 -- does not mean that the same value is being referenced.
4261 -- Note that if the programmer gave an explicit Pure_Function pragma,
4262 -- then we believe the programmer, and leave the subprogram Pure.
4264 -- This code should probably be at the freeze point, so that it
4265 -- happens even on a -gnatc (or more importantly -gnatt) compile
4266 -- so that the semantic tree has Is_Pure set properly ???
4268 if Is_Pure (Spec_Id)
4269 and then Is_Subprogram (Spec_Id)
4270 and then not Has_Pragma_Pure_Function (Spec_Id)
4276 F := First_Formal (Spec_Id);
4277 while Present (F) loop
4278 if Is_Descendent_Of_Address (Etype (F)) then
4279 Set_Is_Pure (Spec_Id, False);
4281 if Spec_Id /= Body_Id then
4282 Set_Is_Pure (Body_Id, False);
4293 -- Initialize any scalar OUT args if Initialize/Normalize_Scalars
4295 if Init_Or_Norm_Scalars and then Is_Subprogram (Spec_Id) then
4300 -- Loop through formals
4302 F := First_Formal (Spec_Id);
4303 while Present (F) loop
4304 if Is_Scalar_Type (Etype (F))
4305 and then Ekind (F) = E_Out_Parameter
4307 -- Insert the initialization. We turn off validity checks
4308 -- for this assignment, since we do not want any check on
4309 -- the initial value itself (which may well be invalid).
4311 Insert_Before_And_Analyze (First (L),
4312 Make_Assignment_Statement (Loc,
4313 Name => New_Occurrence_Of (F, Loc),
4314 Expression => Get_Simple_Init_Val (Etype (F), Loc)),
4315 Suppress => Validity_Check);
4323 Scop := Scope (Spec_Id);
4325 -- Add discriminal renamings to protected subprograms. Install new
4326 -- discriminals for expansion of the next subprogram of this protected
4329 if Is_List_Member (N)
4330 and then Present (Parent (List_Containing (N)))
4331 and then Nkind (Parent (List_Containing (N))) = N_Protected_Body
4333 Add_Discriminal_Declarations
4334 (Declarations (N), Scop, Name_uObject, Loc);
4335 Add_Private_Declarations
4336 (Declarations (N), Scop, Name_uObject, Loc);
4338 -- Associate privals and discriminals with the next protected
4339 -- operation body to be expanded. These are used to expand references
4340 -- to private data objects and discriminants, respectively.
4342 Next_Op := Next_Protected_Operation (N);
4344 if Present (Next_Op) then
4345 Dec := Parent (Base_Type (Scop));
4346 Set_Privals (Dec, Next_Op, Loc);
4347 Set_Discriminals (Dec);
4351 -- Clear out statement list for stubbed procedure
4353 if Present (Corresponding_Spec (N)) then
4354 Set_Elaboration_Flag (N, Spec_Id);
4356 if Convention (Spec_Id) = Convention_Stubbed
4357 or else Is_Eliminated (Spec_Id)
4359 Set_Declarations (N, Empty_List);
4360 Set_Handled_Statement_Sequence (N,
4361 Make_Handled_Sequence_Of_Statements (Loc,
4362 Statements => New_List (
4363 Make_Null_Statement (Loc))));
4368 -- Returns_By_Ref flag is normally set when the subprogram is frozen
4369 -- but subprograms with no specs are not frozen.
4372 Typ : constant Entity_Id := Etype (Spec_Id);
4373 Utyp : constant Entity_Id := Underlying_Type (Typ);
4376 if not Acts_As_Spec (N)
4377 and then Nkind (Parent (Parent (Spec_Id))) /=
4378 N_Subprogram_Body_Stub
4382 elsif Is_Inherently_Limited_Type (Typ) then
4383 Set_Returns_By_Ref (Spec_Id);
4385 elsif Present (Utyp) and then CW_Or_Controlled_Type (Utyp) then
4386 Set_Returns_By_Ref (Spec_Id);
4390 -- For a procedure, we add a return for all possible syntactic ends
4391 -- of the subprogram. Note that reanalysis is not necessary in this
4392 -- case since it would require a lot of work and accomplish nothing.
4394 if Ekind (Spec_Id) = E_Procedure
4395 or else Ekind (Spec_Id) = E_Generic_Procedure
4397 Add_Return (Statements (H));
4399 if Present (Exception_Handlers (H)) then
4400 Except_H := First_Non_Pragma (Exception_Handlers (H));
4401 while Present (Except_H) loop
4402 Add_Return (Statements (Except_H));
4403 Next_Non_Pragma (Except_H);
4407 -- For a function, we must deal with the case where there is at least
4408 -- one missing return. What we do is to wrap the entire body of the
4409 -- function in a block:
4422 -- raise Program_Error;
4425 -- This approach is necessary because the raise must be signalled
4426 -- to the caller, not handled by any local handler (RM 6.4(11)).
4428 -- Note: we do not need to analyze the constructed sequence here,
4429 -- since it has no handler, and an attempt to analyze the handled
4430 -- statement sequence twice is risky in various ways (e.g. the
4431 -- issue of expanding cleanup actions twice).
4433 elsif Has_Missing_Return (Spec_Id) then
4435 Hloc : constant Source_Ptr := Sloc (H);
4436 Blok : constant Node_Id :=
4437 Make_Block_Statement (Hloc,
4438 Handled_Statement_Sequence => H);
4439 Rais : constant Node_Id :=
4440 Make_Raise_Program_Error (Hloc,
4441 Reason => PE_Missing_Return);
4444 Set_Handled_Statement_Sequence (N,
4445 Make_Handled_Sequence_Of_Statements (Hloc,
4446 Statements => New_List (Blok, Rais)));
4448 Push_Scope (Spec_Id);
4455 -- If subprogram contains a parameterless recursive call, then we may
4456 -- have an infinite recursion, so see if we can generate code to check
4457 -- for this possibility if storage checks are not suppressed.
4459 if Ekind (Spec_Id) = E_Procedure
4460 and then Has_Recursive_Call (Spec_Id)
4461 and then not Storage_Checks_Suppressed (Spec_Id)
4463 Detect_Infinite_Recursion (N, Spec_Id);
4466 -- Finally, if we are in Normalize_Scalars mode, then any scalar out
4467 -- parameters must be initialized to the appropriate default value.
4469 if Ekind (Spec_Id) = E_Procedure and then Normalize_Scalars then
4476 Formal := First_Formal (Spec_Id);
4477 while Present (Formal) loop
4478 Floc := Sloc (Formal);
4480 if Ekind (Formal) = E_Out_Parameter
4481 and then Is_Scalar_Type (Etype (Formal))
4484 Make_Assignment_Statement (Floc,
4485 Name => New_Occurrence_Of (Formal, Floc),
4487 Get_Simple_Init_Val (Etype (Formal), Floc));
4488 Prepend (Stm, Declarations (N));
4492 Next_Formal (Formal);
4497 -- Set to encode entity names in package body before gigi is called
4499 Qualify_Entity_Names (N);
4500 end Expand_N_Subprogram_Body;
4502 -----------------------------------
4503 -- Expand_N_Subprogram_Body_Stub --
4504 -----------------------------------
4506 procedure Expand_N_Subprogram_Body_Stub (N : Node_Id) is
4508 if Present (Corresponding_Body (N)) then
4509 Expand_N_Subprogram_Body (
4510 Unit_Declaration_Node (Corresponding_Body (N)));
4512 end Expand_N_Subprogram_Body_Stub;
4514 -------------------------------------
4515 -- Expand_N_Subprogram_Declaration --
4516 -------------------------------------
4518 -- If the declaration appears within a protected body, it is a private
4519 -- operation of the protected type. We must create the corresponding
4520 -- protected subprogram an associated formals. For a normal protected
4521 -- operation, this is done when expanding the protected type declaration.
4523 -- If the declaration is for a null procedure, emit null body
4525 procedure Expand_N_Subprogram_Declaration (N : Node_Id) is
4526 Loc : constant Source_Ptr := Sloc (N);
4527 Subp : constant Entity_Id := Defining_Entity (N);
4528 Scop : constant Entity_Id := Scope (Subp);
4529 Prot_Decl : Node_Id;
4531 Prot_Id : Entity_Id;
4534 -- Deal with case of protected subprogram. Do not generate protected
4535 -- operation if operation is flagged as eliminated.
4537 if Is_List_Member (N)
4538 and then Present (Parent (List_Containing (N)))
4539 and then Nkind (Parent (List_Containing (N))) = N_Protected_Body
4540 and then Is_Protected_Type (Scop)
4542 if No (Protected_Body_Subprogram (Subp))
4543 and then not Is_Eliminated (Subp)
4546 Make_Subprogram_Declaration (Loc,
4548 Build_Protected_Sub_Specification
4549 (N, Scop, Unprotected_Mode));
4551 -- The protected subprogram is declared outside of the protected
4552 -- body. Given that the body has frozen all entities so far, we
4553 -- analyze the subprogram and perform freezing actions explicitly.
4554 -- including the generation of an explicit freeze node, to ensure
4555 -- that gigi has the proper order of elaboration.
4556 -- If the body is a subunit, the insertion point is before the
4557 -- stub in the parent.
4559 Prot_Bod := Parent (List_Containing (N));
4561 if Nkind (Parent (Prot_Bod)) = N_Subunit then
4562 Prot_Bod := Corresponding_Stub (Parent (Prot_Bod));
4565 Insert_Before (Prot_Bod, Prot_Decl);
4566 Prot_Id := Defining_Unit_Name (Specification (Prot_Decl));
4567 Set_Has_Delayed_Freeze (Prot_Id);
4569 Push_Scope (Scope (Scop));
4570 Analyze (Prot_Decl);
4571 Insert_Actions (N, Freeze_Entity (Prot_Id, Loc));
4572 Set_Protected_Body_Subprogram (Subp, Prot_Id);
4576 -- Ada 2005 (AI-348): Generation of the null body
4578 elsif Nkind (Specification (N)) = N_Procedure_Specification
4579 and then Null_Present (Specification (N))
4582 Bod : constant Node_Id :=
4583 Make_Subprogram_Body (Loc,
4585 New_Copy_Tree (Specification (N)),
4586 Declarations => New_List,
4587 Handled_Statement_Sequence =>
4588 Make_Handled_Sequence_Of_Statements (Loc,
4589 Statements => New_List (Make_Null_Statement (Loc))));
4591 Set_Body_To_Inline (N, Bod);
4592 Insert_After (N, Bod);
4595 -- Corresponding_Spec isn't being set by Analyze_Subprogram_Body,
4596 -- evidently because Set_Has_Completion is called earlier for null
4597 -- procedures in Analyze_Subprogram_Declaration, so we force its
4598 -- setting here. If the setting of Has_Completion is not set
4599 -- earlier, then it can result in missing body errors if other
4600 -- errors were already reported (since expansion is turned off).
4602 -- Should creation of the empty body be moved to the analyzer???
4604 Set_Corresponding_Spec (Bod, Defining_Entity (Specification (N)));
4607 end Expand_N_Subprogram_Declaration;
4609 ---------------------------------------
4610 -- Expand_Protected_Object_Reference --
4611 ---------------------------------------
4613 function Expand_Protected_Object_Reference
4615 Scop : Entity_Id) return Node_Id
4617 Loc : constant Source_Ptr := Sloc (N);
4625 Make_Identifier (Loc,
4626 Chars => Name_uObject);
4627 Set_Etype (Rec, Corresponding_Record_Type (Scop));
4629 -- Find enclosing protected operation, and retrieve its first parameter,
4630 -- which denotes the enclosing protected object. If the enclosing
4631 -- operation is an entry, we are immediately within the protected body,
4632 -- and we can retrieve the object from the service entries procedure. A
4633 -- barrier function has has the same signature as an entry. A barrier
4634 -- function is compiled within the protected object, but unlike
4635 -- protected operations its never needs locks, so that its protected
4636 -- body subprogram points to itself.
4638 Proc := Current_Scope;
4639 while Present (Proc)
4640 and then Scope (Proc) /= Scop
4642 Proc := Scope (Proc);
4645 Corr := Protected_Body_Subprogram (Proc);
4649 -- Previous error left expansion incomplete.
4650 -- Nothing to do on this call.
4657 (First (Parameter_Specifications (Parent (Corr))));
4659 if Is_Subprogram (Proc)
4660 and then Proc /= Corr
4662 -- Protected function or procedure
4664 Set_Entity (Rec, Param);
4666 -- Rec is a reference to an entity which will not be in scope when
4667 -- the call is reanalyzed, and needs no further analysis.
4672 -- Entry or barrier function for entry body. The first parameter of
4673 -- the entry body procedure is pointer to the object. We create a
4674 -- local variable of the proper type, duplicating what is done to
4675 -- define _object later on.
4679 Obj_Ptr : constant Entity_Id := Make_Defining_Identifier (Loc,
4681 New_Internal_Name ('T'));
4685 Make_Full_Type_Declaration (Loc,
4686 Defining_Identifier => Obj_Ptr,
4688 Make_Access_To_Object_Definition (Loc,
4689 Subtype_Indication =>
4691 (Corresponding_Record_Type (Scop), Loc))));
4693 Insert_Actions (N, Decls);
4694 Insert_Actions (N, Freeze_Entity (Obj_Ptr, Sloc (N)));
4697 Make_Explicit_Dereference (Loc,
4698 Unchecked_Convert_To (Obj_Ptr,
4699 New_Occurrence_Of (Param, Loc)));
4701 -- Analyze new actual. Other actuals in calls are already analyzed
4702 -- and the list of actuals is not reanalyzed after rewriting.
4704 Set_Parent (Rec, N);
4710 end Expand_Protected_Object_Reference;
4712 --------------------------------------
4713 -- Expand_Protected_Subprogram_Call --
4714 --------------------------------------
4716 procedure Expand_Protected_Subprogram_Call
4724 -- If the protected object is not an enclosing scope, this is
4725 -- an inter-object function call. Inter-object procedure
4726 -- calls are expanded by Exp_Ch9.Build_Simple_Entry_Call.
4727 -- The call is intra-object only if the subprogram being
4728 -- called is in the protected body being compiled, and if the
4729 -- protected object in the call is statically the enclosing type.
4730 -- The object may be an component of some other data structure,
4731 -- in which case this must be handled as an inter-object call.
4733 if not In_Open_Scopes (Scop)
4734 or else not Is_Entity_Name (Name (N))
4736 if Nkind (Name (N)) = N_Selected_Component then
4737 Rec := Prefix (Name (N));
4740 pragma Assert (Nkind (Name (N)) = N_Indexed_Component);
4741 Rec := Prefix (Prefix (Name (N)));
4744 Build_Protected_Subprogram_Call (N,
4745 Name => New_Occurrence_Of (Subp, Sloc (N)),
4746 Rec => Convert_Concurrent (Rec, Etype (Rec)),
4750 Rec := Expand_Protected_Object_Reference (N, Scop);
4756 Build_Protected_Subprogram_Call (N,
4765 -- If it is a function call it can appear in elaboration code and
4766 -- the called entity must be frozen here.
4768 if Ekind (Subp) = E_Function then
4769 Freeze_Expression (Name (N));
4771 end Expand_Protected_Subprogram_Call;
4773 --------------------------------
4774 -- Is_Build_In_Place_Function --
4775 --------------------------------
4777 function Is_Build_In_Place_Function (E : Entity_Id) return Boolean is
4779 -- For now we test whether E denotes a function or access-to-function
4780 -- type whose result subtype is inherently limited. Later this test may
4781 -- be revised to allow composite nonlimited types. Functions with a
4782 -- foreign convention or whose result type has a foreign convention
4785 if Ekind (E) = E_Function
4786 or else Ekind (E) = E_Generic_Function
4787 or else (Ekind (E) = E_Subprogram_Type
4788 and then Etype (E) /= Standard_Void_Type)
4790 -- Note: If you have Convention (C) on an inherently limited type,
4791 -- you're on your own. That is, the C code will have to be carefully
4792 -- written to know about the Ada conventions.
4794 if Has_Foreign_Convention (E)
4795 or else Has_Foreign_Convention (Etype (E))
4799 -- If the return type is a limited interface it has to be treated
4800 -- as a return in place, even if the actual object is some non-
4801 -- limited descendant.
4803 elsif Is_Limited_Interface (Etype (E)) then
4807 return Is_Inherently_Limited_Type (Etype (E))
4808 and then Ada_Version >= Ada_05
4809 and then not Debug_Flag_Dot_L;
4815 end Is_Build_In_Place_Function;
4817 -------------------------------------
4818 -- Is_Build_In_Place_Function_Call --
4819 -------------------------------------
4821 function Is_Build_In_Place_Function_Call (N : Node_Id) return Boolean is
4822 Exp_Node : Node_Id := N;
4823 Function_Id : Entity_Id;
4826 -- Step past qualification or unchecked conversion (the latter can occur
4827 -- in cases of calls to 'Input).
4829 if Nkind (Exp_Node) = N_Qualified_Expression
4830 or else Nkind (Exp_Node) = N_Unchecked_Type_Conversion
4832 Exp_Node := Expression (N);
4835 if Nkind (Exp_Node) /= N_Function_Call then
4839 if Is_Entity_Name (Name (Exp_Node)) then
4840 Function_Id := Entity (Name (Exp_Node));
4842 elsif Nkind (Name (Exp_Node)) = N_Explicit_Dereference then
4843 Function_Id := Etype (Name (Exp_Node));
4846 return Is_Build_In_Place_Function (Function_Id);
4848 end Is_Build_In_Place_Function_Call;
4850 ---------------------------------------
4851 -- Is_Build_In_Place_Function_Return --
4852 ---------------------------------------
4854 function Is_Build_In_Place_Function_Return (N : Node_Id) return Boolean is
4856 if Nkind (N) = N_Simple_Return_Statement
4857 or else Nkind (N) = N_Extended_Return_Statement
4859 return Is_Build_In_Place_Function
4860 (Return_Applies_To (Return_Statement_Entity (N)));
4864 end Is_Build_In_Place_Function_Return;
4866 -----------------------
4867 -- Freeze_Subprogram --
4868 -----------------------
4870 procedure Freeze_Subprogram (N : Node_Id) is
4871 Loc : constant Source_Ptr := Sloc (N);
4873 procedure Register_Predefined_DT_Entry (Prim : Entity_Id);
4874 -- (Ada 2005): Register a predefined primitive in all the secondary
4875 -- dispatch tables of its primitive type.
4877 ----------------------------------
4878 -- Register_Predefined_DT_Entry --
4879 ----------------------------------
4881 procedure Register_Predefined_DT_Entry (Prim : Entity_Id) is
4882 Iface_DT_Ptr : Elmt_Id;
4883 Tagged_Typ : Entity_Id;
4884 Thunk_Id : Entity_Id;
4885 Thunk_Code : Node_Id;
4888 Tagged_Typ := Find_Dispatching_Type (Prim);
4890 if No (Access_Disp_Table (Tagged_Typ))
4891 or else not Has_Abstract_Interfaces (Tagged_Typ)
4892 or else not RTE_Available (RE_Interface_Tag)
4893 or else Restriction_Active (No_Dispatching_Calls)
4898 -- Skip the first access-to-dispatch-table pointer since it leads
4899 -- to the primary dispatch table. We are only concerned with the
4900 -- secondary dispatch table pointers. Note that the access-to-
4901 -- dispatch-table pointer corresponds to the first implemented
4902 -- interface retrieved below.
4905 Next_Elmt (First_Elmt (Access_Disp_Table (Tagged_Typ)));
4907 while Present (Iface_DT_Ptr)
4908 and then Ekind (Node (Iface_DT_Ptr)) = E_Constant
4910 Expand_Interface_Thunk (Prim, Thunk_Id, Thunk_Code);
4912 if Present (Thunk_Code) then
4913 Insert_Actions (N, New_List (
4916 Build_Set_Predefined_Prim_Op_Address (Loc,
4917 Tag_Node => New_Reference_To (Node (Iface_DT_Ptr), Loc),
4918 Position => DT_Position (Prim),
4920 Make_Attribute_Reference (Loc,
4921 Prefix => New_Reference_To (Thunk_Id, Loc),
4922 Attribute_Name => Name_Address))));
4925 Next_Elmt (Iface_DT_Ptr);
4927 end Register_Predefined_DT_Entry;
4931 Subp : constant Entity_Id := Entity (N);
4934 -- We suppress the initialization of the dispatch table entry when
4935 -- VM_Target because the dispatching mechanism is handled internally
4938 if Is_Dispatching_Operation (Subp)
4939 and then not Is_Abstract_Subprogram (Subp)
4940 and then Present (DTC_Entity (Subp))
4941 and then Present (Scope (DTC_Entity (Subp)))
4942 and then VM_Target = No_VM
4943 and then not Restriction_Active (No_Dispatching_Calls)
4944 and then RTE_Available (RE_Tag)
4947 Typ : constant Entity_Id := Scope (DTC_Entity (Subp));
4950 -- Handle private overriden primitives
4952 if not Is_CPP_Class (Typ) then
4953 Check_Overriding_Operation (Subp);
4956 -- We assume that imported CPP primitives correspond with objects
4957 -- whose constructor is in the CPP side; therefore we don't need
4958 -- to generate code to register them in the dispatch table.
4960 if Is_CPP_Class (Typ) then
4963 -- Handle CPP primitives found in derivations of CPP_Class types.
4964 -- These primitives must have been inherited from some parent, and
4965 -- there is no need to register them in the dispatch table because
4966 -- Build_Inherit_Prims takes care of the initialization of these
4969 elsif Is_Imported (Subp)
4970 and then (Convention (Subp) = Convention_CPP
4971 or else Convention (Subp) = Convention_C)
4975 -- Generate code to register the primitive in non statically
4976 -- allocated dispatch tables
4978 elsif not Static_Dispatch_Tables
4980 Is_Library_Level_Tagged_Type (Scope (DTC_Entity (Subp)))
4982 -- When a primitive is frozen, enter its name in its dispatch
4985 if not Is_Interface (Typ)
4986 or else Present (Abstract_Interface_Alias (Subp))
4988 if Is_Predefined_Dispatching_Operation (Subp) then
4989 Register_Predefined_DT_Entry (Subp);
4992 Register_Primitive (Loc,
5000 -- Mark functions that return by reference. Note that it cannot be part
5001 -- of the normal semantic analysis of the spec since the underlying
5002 -- returned type may not be known yet (for private types).
5005 Typ : constant Entity_Id := Etype (Subp);
5006 Utyp : constant Entity_Id := Underlying_Type (Typ);
5008 if Is_Inherently_Limited_Type (Typ) then
5009 Set_Returns_By_Ref (Subp);
5010 elsif Present (Utyp) and then CW_Or_Controlled_Type (Utyp) then
5011 Set_Returns_By_Ref (Subp);
5014 end Freeze_Subprogram;
5016 -------------------------------------------
5017 -- Make_Build_In_Place_Call_In_Allocator --
5018 -------------------------------------------
5020 procedure Make_Build_In_Place_Call_In_Allocator
5021 (Allocator : Node_Id;
5022 Function_Call : Node_Id)
5025 Func_Call : Node_Id := Function_Call;
5026 Function_Id : Entity_Id;
5027 Result_Subt : Entity_Id;
5028 Acc_Type : constant Entity_Id := Etype (Allocator);
5029 New_Allocator : Node_Id;
5030 Return_Obj_Access : Entity_Id;
5033 -- Step past qualification or unchecked conversion (the latter can occur
5034 -- in cases of calls to 'Input).
5036 if Nkind (Func_Call) = N_Qualified_Expression
5037 or else Nkind (Func_Call) = N_Unchecked_Type_Conversion
5039 Func_Call := Expression (Func_Call);
5042 Loc := Sloc (Function_Call);
5044 if Is_Entity_Name (Name (Func_Call)) then
5045 Function_Id := Entity (Name (Func_Call));
5047 elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
5048 Function_Id := Etype (Name (Func_Call));
5051 raise Program_Error;
5054 Result_Subt := Etype (Function_Id);
5056 -- When the result subtype is constrained, the return object must be
5057 -- allocated on the caller side, and access to it is passed to the
5060 -- Here and in related routines, we must examine the full view of the
5061 -- type, because the view at the point of call may differ from that
5062 -- that in the function body, and the expansion mechanism depends on
5063 -- the characteristics of the full view.
5065 if Is_Constrained (Underlying_Type (Result_Subt)) then
5067 -- Replace the initialized allocator of form "new T'(Func (...))"
5068 -- with an uninitialized allocator of form "new T", where T is the
5069 -- result subtype of the called function. The call to the function
5070 -- is handled separately further below.
5073 Make_Allocator (Loc, New_Reference_To (Result_Subt, Loc));
5075 Set_Storage_Pool (New_Allocator, Storage_Pool (Allocator));
5076 Set_Procedure_To_Call (New_Allocator, Procedure_To_Call (Allocator));
5077 Set_No_Initialization (New_Allocator);
5079 Rewrite (Allocator, New_Allocator);
5081 -- Create a new access object and initialize it to the result of the
5082 -- new uninitialized allocator.
5084 Return_Obj_Access :=
5085 Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
5086 Set_Etype (Return_Obj_Access, Acc_Type);
5088 Insert_Action (Allocator,
5089 Make_Object_Declaration (Loc,
5090 Defining_Identifier => Return_Obj_Access,
5091 Object_Definition => New_Reference_To (Acc_Type, Loc),
5092 Expression => Relocate_Node (Allocator)));
5094 -- When the function has a controlling result, an allocation-form
5095 -- parameter must be passed indicating that the caller is allocating
5096 -- the result object. This is needed because such a function can be
5097 -- called as a dispatching operation and must be treated similarly
5098 -- to functions with unconstrained result subtypes.
5100 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5101 (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
5103 Add_Final_List_Actual_To_Build_In_Place_Call
5104 (Func_Call, Function_Id, Acc_Type);
5106 Add_Task_Actuals_To_Build_In_Place_Call
5107 (Func_Call, Function_Id, Master_Actual => Master_Id (Acc_Type));
5109 -- Add an implicit actual to the function call that provides access
5110 -- to the allocated object. An unchecked conversion to the (specific)
5111 -- result subtype of the function is inserted to handle cases where
5112 -- the access type of the allocator has a class-wide designated type.
5114 Add_Access_Actual_To_Build_In_Place_Call
5117 Make_Unchecked_Type_Conversion (Loc,
5118 Subtype_Mark => New_Reference_To (Result_Subt, Loc),
5120 Make_Explicit_Dereference (Loc,
5121 Prefix => New_Reference_To (Return_Obj_Access, Loc))));
5123 -- When the result subtype is unconstrained, the function itself must
5124 -- perform the allocation of the return object, so we pass parameters
5125 -- indicating that. We don't yet handle the case where the allocation
5126 -- must be done in a user-defined storage pool, which will require
5127 -- passing another actual or two to provide allocation/deallocation
5132 -- Pass an allocation parameter indicating that the function should
5133 -- allocate its result on the heap.
5135 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5136 (Func_Call, Function_Id, Alloc_Form => Global_Heap);
5138 Add_Final_List_Actual_To_Build_In_Place_Call
5139 (Func_Call, Function_Id, Acc_Type);
5141 Add_Task_Actuals_To_Build_In_Place_Call
5142 (Func_Call, Function_Id, Master_Actual => Master_Id (Acc_Type));
5144 -- The caller does not provide the return object in this case, so we
5145 -- have to pass null for the object access actual.
5147 Add_Access_Actual_To_Build_In_Place_Call
5148 (Func_Call, Function_Id, Return_Object => Empty);
5151 -- Finally, replace the allocator node with a reference to the result
5152 -- of the function call itself (which will effectively be an access
5153 -- to the object created by the allocator).
5155 Rewrite (Allocator, Make_Reference (Loc, Relocate_Node (Function_Call)));
5156 Analyze_And_Resolve (Allocator, Acc_Type);
5157 end Make_Build_In_Place_Call_In_Allocator;
5159 ---------------------------------------------------
5160 -- Make_Build_In_Place_Call_In_Anonymous_Context --
5161 ---------------------------------------------------
5163 procedure Make_Build_In_Place_Call_In_Anonymous_Context
5164 (Function_Call : Node_Id)
5167 Func_Call : Node_Id := Function_Call;
5168 Function_Id : Entity_Id;
5169 Result_Subt : Entity_Id;
5170 Return_Obj_Id : Entity_Id;
5171 Return_Obj_Decl : Entity_Id;
5174 -- Step past qualification or unchecked conversion (the latter can occur
5175 -- in cases of calls to 'Input).
5177 if Nkind (Func_Call) = N_Qualified_Expression
5178 or else Nkind (Func_Call) = N_Unchecked_Type_Conversion
5180 Func_Call := Expression (Func_Call);
5183 Loc := Sloc (Function_Call);
5185 if Is_Entity_Name (Name (Func_Call)) then
5186 Function_Id := Entity (Name (Func_Call));
5188 elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
5189 Function_Id := Etype (Name (Func_Call));
5192 raise Program_Error;
5195 Result_Subt := Etype (Function_Id);
5197 -- When the result subtype is constrained, an object of the subtype is
5198 -- declared and an access value designating it is passed as an actual.
5200 if Is_Constrained (Underlying_Type (Result_Subt)) then
5202 -- Create a temporary object to hold the function result
5205 Make_Defining_Identifier (Loc,
5206 Chars => New_Internal_Name ('R'));
5207 Set_Etype (Return_Obj_Id, Result_Subt);
5210 Make_Object_Declaration (Loc,
5211 Defining_Identifier => Return_Obj_Id,
5212 Aliased_Present => True,
5213 Object_Definition => New_Reference_To (Result_Subt, Loc));
5215 Set_No_Initialization (Return_Obj_Decl);
5217 Insert_Action (Func_Call, Return_Obj_Decl);
5219 -- When the function has a controlling result, an allocation-form
5220 -- parameter must be passed indicating that the caller is allocating
5221 -- the result object. This is needed because such a function can be
5222 -- called as a dispatching operation and must be treated similarly
5223 -- to functions with unconstrained result subtypes.
5225 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5226 (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
5228 Add_Final_List_Actual_To_Build_In_Place_Call
5229 (Func_Call, Function_Id, Acc_Type => Empty);
5231 Add_Task_Actuals_To_Build_In_Place_Call
5232 (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
5234 -- Add an implicit actual to the function call that provides access
5235 -- to the caller's return object.
5237 Add_Access_Actual_To_Build_In_Place_Call
5238 (Func_Call, Function_Id, New_Reference_To (Return_Obj_Id, Loc));
5240 -- When the result subtype is unconstrained, the function must allocate
5241 -- the return object in the secondary stack, so appropriate implicit
5242 -- parameters are added to the call to indicate that. A transient
5243 -- scope is established to ensure eventual cleanup of the result.
5247 -- Pass an allocation parameter indicating that the function should
5248 -- allocate its result on the secondary stack.
5250 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5251 (Func_Call, Function_Id, Alloc_Form => Secondary_Stack);
5253 Add_Final_List_Actual_To_Build_In_Place_Call
5254 (Func_Call, Function_Id, Acc_Type => Empty);
5256 Add_Task_Actuals_To_Build_In_Place_Call
5257 (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
5259 -- Pass a null value to the function since no return object is
5260 -- available on the caller side.
5262 Add_Access_Actual_To_Build_In_Place_Call
5263 (Func_Call, Function_Id, Empty);
5265 Establish_Transient_Scope (Func_Call, Sec_Stack => True);
5267 end Make_Build_In_Place_Call_In_Anonymous_Context;
5269 ---------------------------------------------------
5270 -- Make_Build_In_Place_Call_In_Assignment --
5271 ---------------------------------------------------
5273 procedure Make_Build_In_Place_Call_In_Assignment
5275 Function_Call : Node_Id)
5277 Lhs : constant Node_Id := Name (Assign);
5279 Func_Call : Node_Id := Function_Call;
5280 Function_Id : Entity_Id;
5281 Result_Subt : Entity_Id;
5282 Ref_Type : Entity_Id;
5283 Ptr_Typ_Decl : Node_Id;
5288 -- Step past qualification or unchecked conversion (the latter can occur
5289 -- in cases of calls to 'Input).
5291 if Nkind (Func_Call) = N_Qualified_Expression
5292 or else Nkind (Func_Call) = N_Unchecked_Type_Conversion
5294 Func_Call := Expression (Func_Call);
5297 Loc := Sloc (Function_Call);
5299 if Is_Entity_Name (Name (Func_Call)) then
5300 Function_Id := Entity (Name (Func_Call));
5302 elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
5303 Function_Id := Etype (Name (Func_Call));
5306 raise Program_Error;
5309 Result_Subt := Etype (Function_Id);
5311 -- When the result subtype is unconstrained, an additional actual must
5312 -- be passed to indicate that the caller is providing the return object.
5313 -- This parameter must also be passed when the called function has a
5314 -- controlling result, because dispatching calls to the function needs
5315 -- to be treated effectively the same as calls to class-wide functions.
5317 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5318 (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
5320 Add_Final_List_Actual_To_Build_In_Place_Call
5321 (Func_Call, Function_Id, Acc_Type => Empty);
5323 Add_Task_Actuals_To_Build_In_Place_Call
5324 (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
5326 -- Add an implicit actual to the function call that provides access to
5327 -- the caller's return object.
5329 Add_Access_Actual_To_Build_In_Place_Call
5332 Make_Unchecked_Type_Conversion (Loc,
5333 Subtype_Mark => New_Reference_To (Result_Subt, Loc),
5334 Expression => Relocate_Node (Lhs)));
5336 -- Create an access type designating the function's result subtype
5339 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
5342 Make_Full_Type_Declaration (Loc,
5343 Defining_Identifier => Ref_Type,
5345 Make_Access_To_Object_Definition (Loc,
5346 All_Present => True,
5347 Subtype_Indication =>
5348 New_Reference_To (Result_Subt, Loc)));
5350 Insert_After_And_Analyze (Assign, Ptr_Typ_Decl);
5352 -- Finally, create an access object initialized to a reference to the
5356 Make_Defining_Identifier (Loc,
5357 Chars => New_Internal_Name ('R'));
5358 Set_Etype (Def_Id, Ref_Type);
5361 Make_Reference (Loc,
5362 Prefix => Relocate_Node (Func_Call));
5364 Insert_After_And_Analyze (Ptr_Typ_Decl,
5365 Make_Object_Declaration (Loc,
5366 Defining_Identifier => Def_Id,
5367 Object_Definition => New_Reference_To (Ref_Type, Loc),
5368 Expression => New_Expr));
5370 Rewrite (Assign, Make_Null_Statement (Loc));
5371 end Make_Build_In_Place_Call_In_Assignment;
5373 ----------------------------------------------------
5374 -- Make_Build_In_Place_Call_In_Object_Declaration --
5375 ----------------------------------------------------
5377 procedure Make_Build_In_Place_Call_In_Object_Declaration
5378 (Object_Decl : Node_Id;
5379 Function_Call : Node_Id)
5382 Obj_Def_Id : constant Entity_Id :=
5383 Defining_Identifier (Object_Decl);
5385 Func_Call : Node_Id := Function_Call;
5386 Function_Id : Entity_Id;
5387 Result_Subt : Entity_Id;
5388 Caller_Object : Node_Id;
5389 Call_Deref : Node_Id;
5390 Ref_Type : Entity_Id;
5391 Ptr_Typ_Decl : Node_Id;
5394 Enclosing_Func : Entity_Id;
5395 Pass_Caller_Acc : Boolean := False;
5398 -- Step past qualification or unchecked conversion (the latter can occur
5399 -- in cases of calls to 'Input).
5401 if Nkind (Func_Call) = N_Qualified_Expression
5402 or else Nkind (Func_Call) = N_Unchecked_Type_Conversion
5404 Func_Call := Expression (Func_Call);
5407 Loc := Sloc (Function_Call);
5409 if Is_Entity_Name (Name (Func_Call)) then
5410 Function_Id := Entity (Name (Func_Call));
5412 elsif Nkind (Name (Func_Call)) = N_Explicit_Dereference then
5413 Function_Id := Etype (Name (Func_Call));
5416 raise Program_Error;
5419 Result_Subt := Etype (Function_Id);
5421 -- In the constrained case, add an implicit actual to the function call
5422 -- that provides access to the declared object. An unchecked conversion
5423 -- to the (specific) result type of the function is inserted to handle
5424 -- the case where the object is declared with a class-wide type.
5426 if Is_Constrained (Underlying_Type (Result_Subt)) then
5428 Make_Unchecked_Type_Conversion (Loc,
5429 Subtype_Mark => New_Reference_To (Result_Subt, Loc),
5430 Expression => New_Reference_To (Obj_Def_Id, Loc));
5432 -- When the function has a controlling result, an allocation-form
5433 -- parameter must be passed indicating that the caller is allocating
5434 -- the result object. This is needed because such a function can be
5435 -- called as a dispatching operation and must be treated similarly
5436 -- to functions with unconstrained result subtypes.
5438 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5439 (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
5441 -- If the function's result subtype is unconstrained and the object is
5442 -- a return object of an enclosing build-in-place function, then the
5443 -- implicit build-in-place parameters of the enclosing function must be
5444 -- passed along to the called function.
5446 elsif Nkind (Parent (Object_Decl)) = N_Extended_Return_Statement then
5447 Pass_Caller_Acc := True;
5449 Enclosing_Func := Enclosing_Subprogram (Obj_Def_Id);
5451 -- If the enclosing function has a constrained result type, then
5452 -- caller allocation will be used.
5454 if Is_Constrained (Etype (Enclosing_Func)) then
5455 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5456 (Func_Call, Function_Id, Alloc_Form => Caller_Allocation);
5458 -- Otherwise, when the enclosing function has an unconstrained result
5459 -- type, the BIP_Alloc_Form formal of the enclosing function must be
5460 -- passed along to the callee.
5463 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5468 (Build_In_Place_Formal (Enclosing_Func, BIP_Alloc_Form),
5472 -- Retrieve the BIPacc formal from the enclosing function and convert
5473 -- it to the access type of the callee's BIP_Object_Access formal.
5476 Make_Unchecked_Type_Conversion (Loc,
5480 (Build_In_Place_Formal (Function_Id, BIP_Object_Access)),
5484 (Build_In_Place_Formal (Enclosing_Func, BIP_Object_Access),
5487 -- In other unconstrained cases, pass an indication to do the allocation
5488 -- on the secondary stack and set Caller_Object to Empty so that a null
5489 -- value will be passed for the caller's object address. A transient
5490 -- scope is established to ensure eventual cleanup of the result.
5493 Add_Alloc_Form_Actual_To_Build_In_Place_Call
5496 Alloc_Form => Secondary_Stack);
5497 Caller_Object := Empty;
5499 Establish_Transient_Scope (Object_Decl, Sec_Stack => True);
5502 Add_Final_List_Actual_To_Build_In_Place_Call
5503 (Func_Call, Function_Id, Acc_Type => Empty);
5505 if Nkind (Parent (Object_Decl)) = N_Extended_Return_Statement
5506 and then Has_Task (Result_Subt)
5508 Enclosing_Func := Enclosing_Subprogram (Obj_Def_Id);
5510 -- Here we're passing along the master that was passed in to this
5513 Add_Task_Actuals_To_Build_In_Place_Call
5514 (Func_Call, Function_Id,
5517 (Build_In_Place_Formal (Enclosing_Func, BIP_Master), Loc));
5520 Add_Task_Actuals_To_Build_In_Place_Call
5521 (Func_Call, Function_Id, Make_Identifier (Loc, Name_uMaster));
5524 Add_Access_Actual_To_Build_In_Place_Call
5525 (Func_Call, Function_Id, Caller_Object, Is_Access => Pass_Caller_Acc);
5527 -- Create an access type designating the function's result subtype
5530 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
5533 Make_Full_Type_Declaration (Loc,
5534 Defining_Identifier => Ref_Type,
5536 Make_Access_To_Object_Definition (Loc,
5537 All_Present => True,
5538 Subtype_Indication =>
5539 New_Reference_To (Result_Subt, Loc)));
5541 -- The access type and its accompanying object must be inserted after
5542 -- the object declaration in the constrained case, so that the function
5543 -- call can be passed access to the object. In the unconstrained case,
5544 -- the access type and object must be inserted before the object, since
5545 -- the object declaration is rewritten to be a renaming of a dereference
5546 -- of the access object.
5548 if Is_Constrained (Underlying_Type (Result_Subt)) then
5549 Insert_After_And_Analyze (Object_Decl, Ptr_Typ_Decl);
5551 Insert_Before_And_Analyze (Object_Decl, Ptr_Typ_Decl);
5554 -- Finally, create an access object initialized to a reference to the
5558 Make_Defining_Identifier (Loc,
5559 Chars => New_Internal_Name ('R'));
5560 Set_Etype (Def_Id, Ref_Type);
5563 Make_Reference (Loc,
5564 Prefix => Relocate_Node (Func_Call));
5566 Insert_After_And_Analyze (Ptr_Typ_Decl,
5567 Make_Object_Declaration (Loc,
5568 Defining_Identifier => Def_Id,
5569 Object_Definition => New_Reference_To (Ref_Type, Loc),
5570 Expression => New_Expr));
5572 if Is_Constrained (Underlying_Type (Result_Subt)) then
5573 Set_Expression (Object_Decl, Empty);
5574 Set_No_Initialization (Object_Decl);
5576 -- In case of an unconstrained result subtype, rewrite the object
5577 -- declaration as an object renaming where the renamed object is a
5578 -- dereference of <function_Call>'reference:
5580 -- Obj : Subt renames <function_call>'Ref.all;
5584 Make_Explicit_Dereference (Loc,
5585 Prefix => New_Reference_To (Def_Id, Loc));
5587 Rewrite (Object_Decl,
5588 Make_Object_Renaming_Declaration (Loc,
5589 Defining_Identifier => Make_Defining_Identifier (Loc,
5590 New_Internal_Name ('D')),
5591 Access_Definition => Empty,
5592 Subtype_Mark => New_Occurrence_Of (Result_Subt, Loc),
5593 Name => Call_Deref));
5595 Set_Renamed_Object (Defining_Identifier (Object_Decl), Call_Deref);
5597 Analyze (Object_Decl);
5599 -- Replace the internal identifier of the renaming declaration's
5600 -- entity with identifier of the original object entity. We also have
5601 -- to exchange the entities containing their defining identifiers to
5602 -- ensure the correct replacement of the object declaration by the
5603 -- object renaming declaration to avoid homograph conflicts (since
5604 -- the object declaration's defining identifier was already entered
5605 -- in current scope).
5607 Set_Chars (Defining_Identifier (Object_Decl), Chars (Obj_Def_Id));
5608 Exchange_Entities (Defining_Identifier (Object_Decl), Obj_Def_Id);
5611 -- If the object entity has a class-wide Etype, then we need to change
5612 -- it to the result subtype of the function call, because otherwise the
5613 -- object will be class-wide without an explicit intialization and won't
5614 -- be allocated properly by the back end. It seems unclean to make such
5615 -- a revision to the type at this point, and we should try to improve
5616 -- this treatment when build-in-place functions with class-wide results
5617 -- are implemented. ???
5619 if Is_Class_Wide_Type (Etype (Defining_Identifier (Object_Decl))) then
5620 Set_Etype (Defining_Identifier (Object_Decl), Result_Subt);
5622 end Make_Build_In_Place_Call_In_Object_Declaration;