1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2004, 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, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, 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_Ch2; use Exp_Ch2;
34 with Exp_Ch3; use Exp_Ch3;
35 with Exp_Ch7; use Exp_Ch7;
36 with Exp_Ch9; use Exp_Ch9;
37 with Exp_Ch11; use Exp_Ch11;
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 Hostparm; use Hostparm;
48 with Inline; use Inline;
50 with Nlists; use Nlists;
51 with Nmake; use Nmake;
53 with Restrict; use Restrict;
54 with Rtsfind; use Rtsfind;
56 with Sem_Ch6; use Sem_Ch6;
57 with Sem_Ch8; use Sem_Ch8;
58 with Sem_Ch12; use Sem_Ch12;
59 with Sem_Ch13; use Sem_Ch13;
60 with Sem_Disp; use Sem_Disp;
61 with Sem_Dist; use Sem_Dist;
62 with Sem_Res; use Sem_Res;
63 with Sem_Util; use Sem_Util;
64 with Sinfo; use Sinfo;
65 with Snames; use Snames;
66 with Stand; use Stand;
67 with Tbuild; use Tbuild;
68 with Ttypes; use Ttypes;
69 with Uintp; use Uintp;
70 with Validsw; use Validsw;
72 package body Exp_Ch6 is
74 -----------------------
75 -- Local Subprograms --
76 -----------------------
78 procedure Check_Overriding_Operation (Subp : Entity_Id);
79 -- Subp is a dispatching operation. Check whether it may override an
80 -- inherited private operation, in which case its DT entry is that of
81 -- the hidden operation, not the one it may have received earlier.
82 -- This must be done before emitting the code to set the corresponding
83 -- DT to the address of the subprogram. The actual placement of Subp in
84 -- the proper place in the list of primitive operations is done in
85 -- Declare_Inherited_Private_Subprograms, which also has to deal with
86 -- implicit operations. This duplication is unavoidable for now???
88 procedure Detect_Infinite_Recursion (N : Node_Id; Spec : Entity_Id);
89 -- This procedure is called only if the subprogram body N, whose spec
90 -- has the given entity Spec, contains a parameterless recursive call.
91 -- It attempts to generate runtime code to detect if this a case of
92 -- infinite recursion.
94 -- The body is scanned to determine dependencies. If the only external
95 -- dependencies are on a small set of scalar variables, then the values
96 -- of these variables are captured on entry to the subprogram, and if
97 -- the values are not changed for the call, we know immediately that
98 -- we have an infinite recursion.
100 procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id);
101 -- For each actual of an in-out parameter which is a numeric conversion
102 -- of the form T(A), where A denotes a variable, we insert the declaration:
104 -- Temp : T := T (A);
106 -- prior to the call. Then we replace the actual with a reference to Temp,
107 -- and append the assignment:
109 -- A := TypeA (Temp);
111 -- after the call. Here TypeA is the actual type of variable A.
112 -- For out parameters, the initial declaration has no expression.
113 -- If A is not an entity name, we generate instead:
115 -- Var : TypeA renames A;
116 -- Temp : T := Var; -- omitting expression for out parameter.
118 -- Var := TypeA (Temp);
120 -- For other in-out parameters, we emit the required constraint checks
121 -- before and/or after the call.
123 -- For all parameter modes, actuals that denote components and slices
124 -- of packed arrays are expanded into suitable temporaries.
126 procedure Expand_Inlined_Call
129 Orig_Subp : Entity_Id);
130 -- If called subprogram can be inlined by the front-end, retrieve the
131 -- analyzed body, replace formals with actuals and expand call in place.
132 -- Generate thunks for actuals that are expressions, and insert the
133 -- corresponding constant declarations before the call. If the original
134 -- call is to a derived operation, the return type is the one of the
135 -- derived operation, but the body is that of the original, so return
136 -- expressions in the body must be converted to the desired type (which
137 -- is simply not noted in the tree without inline expansion).
139 function Expand_Protected_Object_Reference
144 procedure Expand_Protected_Subprogram_Call
148 -- A call to a protected subprogram within the protected object may appear
149 -- as a regular call. The list of actuals must be expanded to contain a
150 -- reference to the object itself, and the call becomes a call to the
151 -- corresponding protected subprogram.
153 --------------------------------
154 -- Check_Overriding_Operation --
155 --------------------------------
157 procedure Check_Overriding_Operation (Subp : Entity_Id) is
158 Typ : constant Entity_Id := Find_Dispatching_Type (Subp);
159 Op_List : constant Elist_Id := Primitive_Operations (Typ);
165 if Is_Derived_Type (Typ)
166 and then not Is_Private_Type (Typ)
167 and then In_Open_Scopes (Scope (Etype (Typ)))
168 and then Typ = Base_Type (Typ)
170 -- Subp overrides an inherited private operation if there is
171 -- an inherited operation with a different name than Subp (see
172 -- Derive_Subprogram) whose Alias is a hidden subprogram with
173 -- the same name as Subp.
175 Op_Elmt := First_Elmt (Op_List);
176 while Present (Op_Elmt) loop
177 Prim_Op := Node (Op_Elmt);
178 Par_Op := Alias (Prim_Op);
181 and then not Comes_From_Source (Prim_Op)
182 and then Chars (Prim_Op) /= Chars (Par_Op)
183 and then Chars (Par_Op) = Chars (Subp)
184 and then Is_Hidden (Par_Op)
185 and then Type_Conformant (Prim_Op, Subp)
187 Set_DT_Position (Subp, DT_Position (Prim_Op));
193 end Check_Overriding_Operation;
195 -------------------------------
196 -- Detect_Infinite_Recursion --
197 -------------------------------
199 procedure Detect_Infinite_Recursion (N : Node_Id; Spec : Entity_Id) is
200 Loc : constant Source_Ptr := Sloc (N);
202 Var_List : constant Elist_Id := New_Elmt_List;
203 -- List of globals referenced by body of procedure
205 Call_List : constant Elist_Id := New_Elmt_List;
206 -- List of recursive calls in body of procedure
208 Shad_List : constant Elist_Id := New_Elmt_List;
209 -- List of entity id's for entities created to capture the
210 -- value of referenced globals on entry to the procedure.
212 Scop : constant Uint := Scope_Depth (Spec);
213 -- This is used to record the scope depth of the current
214 -- procedure, so that we can identify global references.
216 Max_Vars : constant := 4;
217 -- Do not test more than four global variables
219 Count_Vars : Natural := 0;
220 -- Count variables found so far
232 function Process (Nod : Node_Id) return Traverse_Result;
233 -- Function to traverse the subprogram body (using Traverse_Func)
239 function Process (Nod : Node_Id) return Traverse_Result is
243 if Nkind (Nod) = N_Procedure_Call_Statement then
245 -- Case of one of the detected recursive calls
247 if Is_Entity_Name (Name (Nod))
248 and then Has_Recursive_Call (Entity (Name (Nod)))
249 and then Entity (Name (Nod)) = Spec
251 Append_Elmt (Nod, Call_List);
254 -- Any other procedure call may have side effects
260 -- A call to a pure function can always be ignored
262 elsif Nkind (Nod) = N_Function_Call
263 and then Is_Entity_Name (Name (Nod))
264 and then Is_Pure (Entity (Name (Nod)))
268 -- Case of an identifier reference
270 elsif Nkind (Nod) = N_Identifier then
273 -- If no entity, then ignore the reference
275 -- Not clear why this can happen. To investigate, remove this
276 -- test and look at the crash that occurs here in 3401-004 ???
281 -- Ignore entities with no Scope, again not clear how this
282 -- can happen, to investigate, look at 4108-008 ???
284 elsif No (Scope (Ent)) then
287 -- Ignore the reference if not to a more global object
289 elsif Scope_Depth (Scope (Ent)) >= Scop then
292 -- References to types, exceptions and constants are always OK
295 or else Ekind (Ent) = E_Exception
296 or else Ekind (Ent) = E_Constant
300 -- If other than a non-volatile scalar variable, we have some
301 -- kind of global reference (e.g. to a function) that we cannot
302 -- deal with so we forget the attempt.
304 elsif Ekind (Ent) /= E_Variable
305 or else not Is_Scalar_Type (Etype (Ent))
306 or else Treat_As_Volatile (Ent)
310 -- Otherwise we have a reference to a global scalar
313 -- Loop through global entities already detected
315 Elm := First_Elmt (Var_List);
317 -- If not detected before, record this new global reference
320 Count_Vars := Count_Vars + 1;
322 if Count_Vars <= Max_Vars then
323 Append_Elmt (Entity (Nod), Var_List);
330 -- If recorded before, ignore
332 elsif Node (Elm) = Entity (Nod) then
335 -- Otherwise keep looking
345 -- For all other node kinds, recursively visit syntactic children
352 function Traverse_Body is new Traverse_Func;
354 -- Start of processing for Detect_Infinite_Recursion
357 -- Do not attempt detection in No_Implicit_Conditional mode,
358 -- since we won't be able to generate the code to handle the
359 -- recursion in any case.
361 if Restrictions (No_Implicit_Conditionals) then
365 -- Otherwise do traversal and quit if we get abandon signal
367 if Traverse_Body (N) = Abandon then
370 -- We must have a call, since Has_Recursive_Call was set. If not
371 -- just ignore (this is only an error check, so if we have a funny
372 -- situation, due to bugs or errors, we do not want to bomb!)
374 elsif Is_Empty_Elmt_List (Call_List) then
378 -- Here is the case where we detect recursion at compile time
380 -- Push our current scope for analyzing the declarations and
381 -- code that we will insert for the checking.
385 -- This loop builds temporary variables for each of the
386 -- referenced globals, so that at the end of the loop the
387 -- list Shad_List contains these temporaries in one-to-one
388 -- correspondence with the elements in Var_List.
391 Elm := First_Elmt (Var_List);
392 while Present (Elm) loop
395 Make_Defining_Identifier (Loc,
396 Chars => New_Internal_Name ('S'));
397 Append_Elmt (Ent, Shad_List);
399 -- Insert a declaration for this temporary at the start of
400 -- the declarations for the procedure. The temporaries are
401 -- declared as constant objects initialized to the current
402 -- values of the corresponding temporaries.
405 Make_Object_Declaration (Loc,
406 Defining_Identifier => Ent,
407 Object_Definition => New_Occurrence_Of (Etype (Var), Loc),
408 Constant_Present => True,
409 Expression => New_Occurrence_Of (Var, Loc));
412 Prepend (Decl, Declarations (N));
414 Insert_After (Last, Decl);
422 -- Loop through calls
424 Call := First_Elmt (Call_List);
425 while Present (Call) loop
427 -- Build a predicate expression of the form
430 -- and then global1 = temp1
431 -- and then global2 = temp2
434 -- This predicate determines if any of the global values
435 -- referenced by the procedure have changed since the
436 -- current call, if not an infinite recursion is assured.
438 Test := New_Occurrence_Of (Standard_True, Loc);
440 Elm1 := First_Elmt (Var_List);
441 Elm2 := First_Elmt (Shad_List);
442 while Present (Elm1) loop
448 Left_Opnd => New_Occurrence_Of (Node (Elm1), Loc),
449 Right_Opnd => New_Occurrence_Of (Node (Elm2), Loc)));
455 -- Now we replace the call with the sequence
457 -- if no-changes (see above) then
458 -- raise Storage_Error;
463 Rewrite (Node (Call),
464 Make_If_Statement (Loc,
466 Then_Statements => New_List (
467 Make_Raise_Storage_Error (Loc,
468 Reason => SE_Infinite_Recursion)),
470 Else_Statements => New_List (
471 Relocate_Node (Node (Call)))));
473 Analyze (Node (Call));
478 -- Remove temporary scope stack entry used for analysis
481 end Detect_Infinite_Recursion;
487 procedure Expand_Actuals (N : Node_Id; Subp : Entity_Id) is
488 Loc : constant Source_Ptr := Sloc (N);
493 E_Formal : Entity_Id;
495 procedure Add_Call_By_Copy_Code;
496 -- For cases where the parameter must be passed by copy, this routine
497 -- generates a temporary variable into which the actual is copied and
498 -- then passes this as the parameter. For an OUT or IN OUT parameter,
499 -- an assignment is also generated to copy the result back. The call
500 -- also takes care of any constraint checks required for the type
501 -- conversion case (on both the way in and the way out).
503 procedure Add_Packed_Call_By_Copy_Code;
504 -- This is used when the actual involves a reference to an element
505 -- of a packed array, where we can appropriately use a simpler
506 -- approach than the full call by copy code. We just copy the value
507 -- in and out of an appropriate temporary.
509 procedure Check_Fortran_Logical;
510 -- A value of type Logical that is passed through a formal parameter
511 -- must be normalized because .TRUE. usually does not have the same
512 -- representation as True. We assume that .FALSE. = False = 0.
513 -- What about functions that return a logical type ???
515 function Make_Var (Actual : Node_Id) return Entity_Id;
516 -- Returns an entity that refers to the given actual parameter,
517 -- Actual (not including any type conversion). If Actual is an
518 -- entity name, then this entity is returned unchanged, otherwise
519 -- a renaming is created to provide an entity for the actual.
521 procedure Reset_Packed_Prefix;
522 -- The expansion of a packed array component reference is delayed in
523 -- the context of a call. Now we need to complete the expansion, so we
524 -- unmark the analyzed bits in all prefixes.
526 ---------------------------
527 -- Add_Call_By_Copy_Code --
528 ---------------------------
530 procedure Add_Call_By_Copy_Code is
539 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
541 if Nkind (Actual) = N_Type_Conversion then
542 V_Typ := Etype (Expression (Actual));
544 -- If the formal is an (in-)out parameter, capture the name
545 -- of the variable in order to build the post-call assignment.
547 Var := Make_Var (Expression (Actual));
549 Crep := not Same_Representation
550 (Etype (Formal), Etype (Expression (Actual)));
553 V_Typ := Etype (Actual);
554 Var := Make_Var (Actual);
558 -- Setup initialization for case of in out parameter, or an out
559 -- parameter where the formal is an unconstrained array (in the
560 -- latter case, we have to pass in an object with bounds).
562 if Ekind (Formal) = E_In_Out_Parameter
563 or else (Is_Array_Type (Etype (Formal))
565 not Is_Constrained (Etype (Formal)))
567 if Nkind (Actual) = N_Type_Conversion then
568 if Conversion_OK (Actual) then
569 Init := OK_Convert_To
570 (Etype (Formal), New_Occurrence_Of (Var, Loc));
573 (Etype (Formal), New_Occurrence_Of (Var, Loc));
576 Init := New_Occurrence_Of (Var, Loc);
579 -- An initialization is created for packed conversions as
580 -- actuals for out parameters to enable Make_Object_Declaration
581 -- to determine the proper subtype for N_Node. Note that this
582 -- is wasteful because the extra copying on the call side is
583 -- not required for such out parameters. ???
585 elsif Ekind (Formal) = E_Out_Parameter
586 and then Nkind (Actual) = N_Type_Conversion
587 and then (Is_Bit_Packed_Array (Etype (Formal))
589 Is_Bit_Packed_Array (Etype (Expression (Actual))))
591 if Conversion_OK (Actual) then
593 OK_Convert_To (Etype (Formal), New_Occurrence_Of (Var, Loc));
596 Convert_To (Etype (Formal), New_Occurrence_Of (Var, Loc));
603 Make_Object_Declaration (Loc,
604 Defining_Identifier => Temp,
606 New_Occurrence_Of (Etype (Formal), Loc),
608 Set_Assignment_OK (N_Node);
609 Insert_Action (N, N_Node);
611 -- Now, normally the deal here is that we use the defining
612 -- identifier created by that object declaration. There is
613 -- one exception to this. In the change of representation case
614 -- the above declaration will end up looking like:
616 -- temp : type := identifier;
618 -- And in this case we might as well use the identifier directly
619 -- and eliminate the temporary. Note that the analysis of the
620 -- declaration was not a waste of time in that case, since it is
621 -- what generated the necessary change of representation code. If
622 -- the change of representation introduced additional code, as in
623 -- a fixed-integer conversion, the expression is not an identifier
627 and then Present (Expression (N_Node))
628 and then Is_Entity_Name (Expression (N_Node))
630 Temp := Entity (Expression (N_Node));
631 Rewrite (N_Node, Make_Null_Statement (Loc));
634 -- For IN parameter, all we do is to replace the actual
636 if Ekind (Formal) = E_In_Parameter then
637 Rewrite (Actual, New_Reference_To (Temp, Loc));
640 -- Processing for OUT or IN OUT parameter
643 -- If type conversion, use reverse conversion on exit
645 if Nkind (Actual) = N_Type_Conversion then
646 if Conversion_OK (Actual) then
647 Expr := OK_Convert_To (V_Typ, New_Occurrence_Of (Temp, Loc));
649 Expr := Convert_To (V_Typ, New_Occurrence_Of (Temp, Loc));
652 Expr := New_Occurrence_Of (Temp, Loc);
655 Rewrite (Actual, New_Reference_To (Temp, Loc));
658 Append_To (Post_Call,
659 Make_Assignment_Statement (Loc,
660 Name => New_Occurrence_Of (Var, Loc),
661 Expression => Expr));
663 Set_Assignment_OK (Name (Last (Post_Call)));
665 end Add_Call_By_Copy_Code;
667 ----------------------------------
668 -- Add_Packed_Call_By_Copy_Code --
669 ----------------------------------
671 procedure Add_Packed_Call_By_Copy_Code is
681 -- Prepare to generate code
683 Temp := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
684 Incod := Relocate_Node (Actual);
685 Outcod := New_Copy_Tree (Incod);
687 -- Generate declaration of temporary variable, initializing it
688 -- with the input parameter unless we have an OUT variable.
690 if Ekind (Formal) = E_Out_Parameter then
695 Make_Object_Declaration (Loc,
696 Defining_Identifier => Temp,
698 New_Occurrence_Of (Etype (Formal), Loc),
699 Expression => Incod));
701 -- The actual is simply a reference to the temporary
703 Rewrite (Actual, New_Occurrence_Of (Temp, Loc));
705 -- Generate copy out if OUT or IN OUT parameter
707 if Ekind (Formal) /= E_In_Parameter then
709 Rhs := New_Occurrence_Of (Temp, Loc);
711 -- Deal with conversion
713 if Nkind (Lhs) = N_Type_Conversion then
714 Lhs := Expression (Lhs);
715 Rhs := Convert_To (Etype (Actual), Rhs);
718 Append_To (Post_Call,
719 Make_Assignment_Statement (Loc,
723 end Add_Packed_Call_By_Copy_Code;
725 ---------------------------
726 -- Check_Fortran_Logical --
727 ---------------------------
729 procedure Check_Fortran_Logical is
730 Logical : constant Entity_Id := Etype (Formal);
733 -- Note: this is very incomplete, e.g. it does not handle arrays
734 -- of logical values. This is really not the right approach at all???)
737 if Convention (Subp) = Convention_Fortran
738 and then Root_Type (Etype (Formal)) = Standard_Boolean
739 and then Ekind (Formal) /= E_In_Parameter
741 Var := Make_Var (Actual);
742 Append_To (Post_Call,
743 Make_Assignment_Statement (Loc,
744 Name => New_Occurrence_Of (Var, Loc),
746 Unchecked_Convert_To (
749 Left_Opnd => New_Occurrence_Of (Var, Loc),
751 Unchecked_Convert_To (
753 New_Occurrence_Of (Standard_False, Loc))))));
755 end Check_Fortran_Logical;
761 function Make_Var (Actual : Node_Id) return Entity_Id is
765 if Is_Entity_Name (Actual) then
766 return Entity (Actual);
769 Var := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
772 Make_Object_Renaming_Declaration (Loc,
773 Defining_Identifier => Var,
775 New_Occurrence_Of (Etype (Actual), Loc),
776 Name => Relocate_Node (Actual));
778 Insert_Action (N, N_Node);
783 -------------------------
784 -- Reset_Packed_Prefix --
785 -------------------------
787 procedure Reset_Packed_Prefix is
788 Pfx : Node_Id := Actual;
792 Set_Analyzed (Pfx, False);
793 exit when Nkind (Pfx) /= N_Selected_Component
794 and then Nkind (Pfx) /= N_Indexed_Component;
797 end Reset_Packed_Prefix;
799 -- Start of processing for Expand_Actuals
802 Formal := First_Formal (Subp);
803 Actual := First_Actual (N);
805 Post_Call := New_List;
807 while Present (Formal) loop
808 E_Formal := Etype (Formal);
810 if Is_Scalar_Type (E_Formal)
811 or else Nkind (Actual) = N_Slice
813 Check_Fortran_Logical;
817 elsif Ekind (Formal) /= E_Out_Parameter then
819 -- The unusual case of the current instance of a protected type
820 -- requires special handling. This can only occur in the context
821 -- of a call within the body of a protected operation.
823 if Is_Entity_Name (Actual)
824 and then Ekind (Entity (Actual)) = E_Protected_Type
825 and then In_Open_Scopes (Entity (Actual))
827 if Scope (Subp) /= Entity (Actual) then
828 Error_Msg_N ("operation outside protected type may not "
829 & "call back its protected operations?", Actual);
833 Expand_Protected_Object_Reference (N, Entity (Actual)));
836 Apply_Constraint_Check (Actual, E_Formal);
838 -- Out parameter case. No constraint checks on access type
841 elsif Is_Access_Type (E_Formal) then
846 elsif Has_Discriminants (Base_Type (E_Formal))
847 or else Has_Non_Null_Base_Init_Proc (E_Formal)
849 Apply_Constraint_Check (Actual, E_Formal);
854 Apply_Constraint_Check (Actual, Base_Type (E_Formal));
857 -- Processing for IN-OUT and OUT parameters
859 if Ekind (Formal) /= E_In_Parameter then
861 -- For type conversions of arrays, apply length/range checks
863 if Is_Array_Type (E_Formal)
864 and then Nkind (Actual) = N_Type_Conversion
866 if Is_Constrained (E_Formal) then
867 Apply_Length_Check (Expression (Actual), E_Formal);
869 Apply_Range_Check (Expression (Actual), E_Formal);
873 -- If argument is a type conversion for a type that is passed
874 -- by copy, then we must pass the parameter by copy.
876 if Nkind (Actual) = N_Type_Conversion
878 (Is_Numeric_Type (E_Formal)
879 or else Is_Access_Type (E_Formal)
880 or else Is_Enumeration_Type (E_Formal)
881 or else Is_Bit_Packed_Array (Etype (Formal))
882 or else Is_Bit_Packed_Array (Etype (Expression (Actual)))
884 -- Also pass by copy if change of representation
886 or else not Same_Representation
888 Etype (Expression (Actual))))
890 Add_Call_By_Copy_Code;
892 -- References to components of bit packed arrays are expanded
893 -- at this point, rather than at the point of analysis of the
894 -- actuals, to handle the expansion of the assignment to
895 -- [in] out parameters.
897 elsif Is_Ref_To_Bit_Packed_Array (Actual) then
898 Add_Packed_Call_By_Copy_Code;
900 -- References to slices of bit packed arrays are expanded
902 elsif Is_Ref_To_Bit_Packed_Slice (Actual) then
903 Add_Call_By_Copy_Code;
905 -- References to possibly unaligned slices of arrays are expanded
907 elsif Is_Possibly_Unaligned_Slice (Actual) then
908 Add_Call_By_Copy_Code;
910 -- Deal with access types where the actual subtpe and the
911 -- formal subtype are not the same, requiring a check.
913 -- It is necessary to exclude tagged types because of "downward
914 -- conversion" errors and a strange assertion error in namet
915 -- from gnatf in bug 1215-001 ???
917 elsif Is_Access_Type (E_Formal)
918 and then not Same_Type (E_Formal, Etype (Actual))
919 and then not Is_Tagged_Type (Designated_Type (E_Formal))
921 Add_Call_By_Copy_Code;
923 elsif Is_Entity_Name (Actual)
924 and then Treat_As_Volatile (Entity (Actual))
925 and then not Is_Scalar_Type (Etype (Entity (Actual)))
926 and then not Treat_As_Volatile (E_Formal)
928 Add_Call_By_Copy_Code;
930 elsif Nkind (Actual) = N_Indexed_Component
931 and then Is_Entity_Name (Prefix (Actual))
932 and then Has_Volatile_Components (Entity (Prefix (Actual)))
934 Add_Call_By_Copy_Code;
937 -- Processing for IN parameters
940 -- For IN parameters is in the packed array case, we expand an
941 -- indexed component (the circuit in Exp_Ch4 deliberately left
942 -- indexed components appearing as actuals untouched, so that
943 -- the special processing above for the OUT and IN OUT cases
944 -- could be performed. We could make the test in Exp_Ch4 more
945 -- complex and have it detect the parameter mode, but it is
946 -- easier simply to handle all cases here.
948 if Nkind (Actual) = N_Indexed_Component
949 and then Is_Packed (Etype (Prefix (Actual)))
952 Expand_Packed_Element_Reference (Actual);
954 -- If we have a reference to a bit packed array, we copy it,
955 -- since the actual must be byte aligned.
957 -- Is this really necessary in all cases???
959 elsif Is_Ref_To_Bit_Packed_Array (Actual) then
960 Add_Packed_Call_By_Copy_Code;
962 -- Similarly, we have to expand slices of packed arrays here
963 -- because the result must be byte aligned.
965 elsif Is_Ref_To_Bit_Packed_Slice (Actual) then
966 Add_Call_By_Copy_Code;
968 -- Only processing remaining is to pass by copy if this is a
969 -- reference to a possibly unaligned slice, since the caller
970 -- expects an appropriately aligned argument.
972 elsif Is_Possibly_Unaligned_Slice (Actual) then
973 Add_Call_By_Copy_Code;
977 Next_Formal (Formal);
978 Next_Actual (Actual);
981 -- Find right place to put post call stuff if it is present
983 if not Is_Empty_List (Post_Call) then
985 -- If call is not a list member, it must be the triggering
986 -- statement of a triggering alternative or an entry call
987 -- alternative, and we can add the post call stuff to the
988 -- corresponding statement list.
990 if not Is_List_Member (N) then
992 P : constant Node_Id := Parent (N);
995 pragma Assert (Nkind (P) = N_Triggering_Alternative
996 or else Nkind (P) = N_Entry_Call_Alternative);
998 if Is_Non_Empty_List (Statements (P)) then
999 Insert_List_Before_And_Analyze
1000 (First (Statements (P)), Post_Call);
1002 Set_Statements (P, Post_Call);
1006 -- Otherwise, normal case where N is in a statement sequence,
1007 -- just put the post-call stuff after the call statement.
1010 Insert_Actions_After (N, Post_Call);
1014 -- The call node itself is re-analyzed in Expand_Call.
1022 -- This procedure handles expansion of function calls and procedure call
1023 -- statements (i.e. it serves as the body for Expand_N_Function_Call and
1024 -- Expand_N_Procedure_Call_Statement. Processing for calls includes:
1026 -- Replace call to Raise_Exception by Raise_Exception always if possible
1027 -- Provide values of actuals for all formals in Extra_Formals list
1028 -- Replace "call" to enumeration literal function by literal itself
1029 -- Rewrite call to predefined operator as operator
1030 -- Replace actuals to in-out parameters that are numeric conversions,
1031 -- with explicit assignment to temporaries before and after the call.
1032 -- Remove optional actuals if First_Optional_Parameter specified.
1034 -- Note that the list of actuals has been filled with default expressions
1035 -- during semantic analysis of the call. Only the extra actuals required
1036 -- for the 'Constrained attribute and for accessibility checks are added
1039 procedure Expand_Call (N : Node_Id) is
1040 Loc : constant Source_Ptr := Sloc (N);
1041 Remote : constant Boolean := Is_Remote_Call (N);
1043 Orig_Subp : Entity_Id := Empty;
1044 Parent_Subp : Entity_Id;
1045 Parent_Formal : Entity_Id;
1048 Prev : Node_Id := Empty;
1049 Prev_Orig : Node_Id;
1051 Extra_Actuals : List_Id := No_List;
1054 procedure Add_Actual_Parameter (Insert_Param : Node_Id);
1055 -- Adds one entry to the end of the actual parameter list. Used for
1056 -- default parameters and for extra actuals (for Extra_Formals).
1057 -- The argument is an N_Parameter_Association node.
1059 procedure Add_Extra_Actual (Expr : Node_Id; EF : Entity_Id);
1060 -- Adds an extra actual to the list of extra actuals. Expr
1061 -- is the expression for the value of the actual, EF is the
1062 -- entity for the extra formal.
1064 function Inherited_From_Formal (S : Entity_Id) return Entity_Id;
1065 -- Within an instance, a type derived from a non-tagged formal derived
1066 -- type inherits from the original parent, not from the actual. This is
1067 -- tested in 4723-003. The current derivation mechanism has the derived
1068 -- type inherit from the actual, which is only correct outside of the
1069 -- instance. If the subprogram is inherited, we test for this particular
1070 -- case through a convoluted tree traversal before setting the proper
1071 -- subprogram to be called.
1073 --------------------------
1074 -- Add_Actual_Parameter --
1075 --------------------------
1077 procedure Add_Actual_Parameter (Insert_Param : Node_Id) is
1078 Actual_Expr : constant Node_Id :=
1079 Explicit_Actual_Parameter (Insert_Param);
1082 -- Case of insertion is first named actual
1084 if No (Prev) or else
1085 Nkind (Parent (Prev)) /= N_Parameter_Association
1087 Set_Next_Named_Actual (Insert_Param, First_Named_Actual (N));
1088 Set_First_Named_Actual (N, Actual_Expr);
1091 if not Present (Parameter_Associations (N)) then
1092 Set_Parameter_Associations (N, New_List);
1093 Append (Insert_Param, Parameter_Associations (N));
1096 Insert_After (Prev, Insert_Param);
1099 -- Case of insertion is not first named actual
1102 Set_Next_Named_Actual
1103 (Insert_Param, Next_Named_Actual (Parent (Prev)));
1104 Set_Next_Named_Actual (Parent (Prev), Actual_Expr);
1105 Append (Insert_Param, Parameter_Associations (N));
1108 Prev := Actual_Expr;
1109 end Add_Actual_Parameter;
1111 ----------------------
1112 -- Add_Extra_Actual --
1113 ----------------------
1115 procedure Add_Extra_Actual (Expr : Node_Id; EF : Entity_Id) is
1116 Loc : constant Source_Ptr := Sloc (Expr);
1119 if Extra_Actuals = No_List then
1120 Extra_Actuals := New_List;
1121 Set_Parent (Extra_Actuals, N);
1124 Append_To (Extra_Actuals,
1125 Make_Parameter_Association (Loc,
1126 Explicit_Actual_Parameter => Expr,
1128 Make_Identifier (Loc, Chars (EF))));
1130 Analyze_And_Resolve (Expr, Etype (EF));
1131 end Add_Extra_Actual;
1133 ---------------------------
1134 -- Inherited_From_Formal --
1135 ---------------------------
1137 function Inherited_From_Formal (S : Entity_Id) return Entity_Id is
1139 Gen_Par : Entity_Id;
1140 Gen_Prim : Elist_Id;
1145 -- If the operation is inherited, it is attached to the corresponding
1146 -- type derivation. If the parent in the derivation is a generic
1147 -- actual, it is a subtype of the actual, and we have to recover the
1148 -- original derived type declaration to find the proper parent.
1150 if Nkind (Parent (S)) /= N_Full_Type_Declaration
1151 or else not Is_Derived_Type (Defining_Identifier (Parent (S)))
1152 or else Nkind (Type_Definition (Original_Node (Parent (S))))
1153 /= N_Derived_Type_Definition
1154 or else not In_Instance
1161 (Type_Definition (Original_Node (Parent (S)))));
1163 if Nkind (Indic) = N_Subtype_Indication then
1164 Par := Entity (Subtype_Mark (Indic));
1166 Par := Entity (Indic);
1170 if not Is_Generic_Actual_Type (Par)
1171 or else Is_Tagged_Type (Par)
1172 or else Nkind (Parent (Par)) /= N_Subtype_Declaration
1173 or else not In_Open_Scopes (Scope (Par))
1178 Gen_Par := Generic_Parent_Type (Parent (Par));
1181 -- If the generic parent type is still the generic type, this
1182 -- is a private formal, not a derived formal, and there are no
1183 -- operations inherited from the formal.
1185 if Nkind (Parent (Gen_Par)) = N_Formal_Type_Declaration then
1189 Gen_Prim := Collect_Primitive_Operations (Gen_Par);
1190 Elmt := First_Elmt (Gen_Prim);
1192 while Present (Elmt) loop
1193 if Chars (Node (Elmt)) = Chars (S) then
1199 F1 := First_Formal (S);
1200 F2 := First_Formal (Node (Elmt));
1203 and then Present (F2)
1206 if Etype (F1) = Etype (F2)
1207 or else Etype (F2) = Gen_Par
1213 exit; -- not the right subprogram
1225 raise Program_Error;
1226 end Inherited_From_Formal;
1228 -- Start of processing for Expand_Call
1231 -- Ignore if previous error
1233 if Nkind (N) in N_Has_Etype and then Etype (N) = Any_Type then
1237 -- Call using access to subprogram with explicit dereference
1239 if Nkind (Name (N)) = N_Explicit_Dereference then
1240 Subp := Etype (Name (N));
1241 Parent_Subp := Empty;
1243 -- Case of call to simple entry, where the Name is a selected component
1244 -- whose prefix is the task, and whose selector name is the entry name
1246 elsif Nkind (Name (N)) = N_Selected_Component then
1247 Subp := Entity (Selector_Name (Name (N)));
1248 Parent_Subp := Empty;
1250 -- Case of call to member of entry family, where Name is an indexed
1251 -- component, with the prefix being a selected component giving the
1252 -- task and entry family name, and the index being the entry index.
1254 elsif Nkind (Name (N)) = N_Indexed_Component then
1255 Subp := Entity (Selector_Name (Prefix (Name (N))));
1256 Parent_Subp := Empty;
1261 Subp := Entity (Name (N));
1262 Parent_Subp := Alias (Subp);
1264 -- Replace call to Raise_Exception by call to Raise_Exception_Always
1265 -- if we can tell that the first parameter cannot possibly be null.
1266 -- This helps optimization and also generation of warnings.
1268 if not Restrictions (No_Exception_Handlers)
1269 and then Is_RTE (Subp, RE_Raise_Exception)
1272 FA : constant Node_Id := Original_Node (First_Actual (N));
1275 -- The case we catch is where the first argument is obtained
1276 -- using the Identity attribute (which must always be non-null)
1278 if Nkind (FA) = N_Attribute_Reference
1279 and then Attribute_Name (FA) = Name_Identity
1281 Subp := RTE (RE_Raise_Exception_Always);
1282 Set_Entity (Name (N), Subp);
1287 if Ekind (Subp) = E_Entry then
1288 Parent_Subp := Empty;
1292 -- First step, compute extra actuals, corresponding to any
1293 -- Extra_Formals present. Note that we do not access Extra_Formals
1294 -- directly, instead we simply note the presence of the extra
1295 -- formals as we process the regular formals and collect the
1296 -- corresponding actuals in Extra_Actuals.
1298 -- We also generate any required range checks for actuals as we go
1299 -- through the loop, since this is a convenient place to do this.
1301 Formal := First_Formal (Subp);
1302 Actual := First_Actual (N);
1303 while Present (Formal) loop
1305 -- Generate range check if required (not activated yet ???)
1307 -- if Do_Range_Check (Actual) then
1308 -- Set_Do_Range_Check (Actual, False);
1309 -- Generate_Range_Check
1310 -- (Actual, Etype (Formal), CE_Range_Check_Failed);
1313 -- Prepare to examine current entry
1316 Prev_Orig := Original_Node (Prev);
1318 -- Create possible extra actual for constrained case. Usually,
1319 -- the extra actual is of the form actual'constrained, but since
1320 -- this attribute is only available for unconstrained records,
1321 -- TRUE is expanded if the type of the formal happens to be
1322 -- constrained (for instance when this procedure is inherited
1323 -- from an unconstrained record to a constrained one) or if the
1324 -- actual has no discriminant (its type is constrained). An
1325 -- exception to this is the case of a private type without
1326 -- discriminants. In this case we pass FALSE because the
1327 -- object has underlying discriminants with defaults.
1329 if Present (Extra_Constrained (Formal)) then
1330 if Ekind (Etype (Prev)) in Private_Kind
1331 and then not Has_Discriminants (Base_Type (Etype (Prev)))
1334 New_Occurrence_Of (Standard_False, Loc),
1335 Extra_Constrained (Formal));
1337 elsif Is_Constrained (Etype (Formal))
1338 or else not Has_Discriminants (Etype (Prev))
1341 New_Occurrence_Of (Standard_True, Loc),
1342 Extra_Constrained (Formal));
1345 -- If the actual is a type conversion, then the constrained
1346 -- test applies to the actual, not the target type.
1349 Act_Prev : Node_Id := Prev;
1352 -- Test for unchecked conversions as well, which can
1353 -- occur as out parameter actuals on calls to stream
1356 while Nkind (Act_Prev) = N_Type_Conversion
1357 or else Nkind (Act_Prev) = N_Unchecked_Type_Conversion
1359 Act_Prev := Expression (Act_Prev);
1363 Make_Attribute_Reference (Sloc (Prev),
1365 Duplicate_Subexpr_No_Checks
1366 (Act_Prev, Name_Req => True),
1367 Attribute_Name => Name_Constrained),
1368 Extra_Constrained (Formal));
1373 -- Create possible extra actual for accessibility level
1375 if Present (Extra_Accessibility (Formal)) then
1376 if Is_Entity_Name (Prev_Orig) then
1378 -- When passing an access parameter as the actual to another
1379 -- access parameter we need to pass along the actual's own
1380 -- associated access level parameter. This is done is we are
1381 -- in the scope of the formal access parameter (if this is an
1382 -- inlined body the extra formal is irrelevant).
1384 if Ekind (Entity (Prev_Orig)) in Formal_Kind
1385 and then Ekind (Etype (Prev_Orig)) = E_Anonymous_Access_Type
1386 and then In_Open_Scopes (Scope (Entity (Prev_Orig)))
1389 Parm_Ent : constant Entity_Id := Param_Entity (Prev_Orig);
1392 pragma Assert (Present (Parm_Ent));
1394 if Present (Extra_Accessibility (Parm_Ent)) then
1397 (Extra_Accessibility (Parm_Ent), Loc),
1398 Extra_Accessibility (Formal));
1400 -- If the actual access parameter does not have an
1401 -- associated extra formal providing its scope level,
1402 -- then treat the actual as having library-level
1407 Make_Integer_Literal (Loc,
1408 Intval => Scope_Depth (Standard_Standard)),
1409 Extra_Accessibility (Formal));
1413 -- The actual is a normal access value, so just pass the
1414 -- level of the actual's access type.
1418 Make_Integer_Literal (Loc,
1419 Intval => Type_Access_Level (Etype (Prev_Orig))),
1420 Extra_Accessibility (Formal));
1424 case Nkind (Prev_Orig) is
1426 when N_Attribute_Reference =>
1428 case Get_Attribute_Id (Attribute_Name (Prev_Orig)) is
1430 -- For X'Access, pass on the level of the prefix X
1432 when Attribute_Access =>
1434 Make_Integer_Literal (Loc,
1436 Object_Access_Level (Prefix (Prev_Orig))),
1437 Extra_Accessibility (Formal));
1439 -- Treat the unchecked attributes as library-level
1441 when Attribute_Unchecked_Access |
1442 Attribute_Unrestricted_Access =>
1444 Make_Integer_Literal (Loc,
1445 Intval => Scope_Depth (Standard_Standard)),
1446 Extra_Accessibility (Formal));
1448 -- No other cases of attributes returning access
1449 -- values that can be passed to access parameters
1452 raise Program_Error;
1456 -- For allocators we pass the level of the execution of
1457 -- the called subprogram, which is one greater than the
1458 -- current scope level.
1462 Make_Integer_Literal (Loc,
1463 Scope_Depth (Current_Scope) + 1),
1464 Extra_Accessibility (Formal));
1466 -- For other cases we simply pass the level of the
1467 -- actual's access type.
1471 Make_Integer_Literal (Loc,
1472 Intval => Type_Access_Level (Etype (Prev_Orig))),
1473 Extra_Accessibility (Formal));
1479 -- Perform the check of 4.6(49) that prevents a null value
1480 -- from being passed as an actual to an access parameter.
1481 -- Note that the check is elided in the common cases of
1482 -- passing an access attribute or access parameter as an
1483 -- actual. Also, we currently don't enforce this check for
1484 -- expander-generated actuals and when -gnatdj is set.
1486 if Ekind (Etype (Formal)) /= E_Anonymous_Access_Type
1487 or else Access_Checks_Suppressed (Subp)
1491 elsif Debug_Flag_J then
1494 elsif not Comes_From_Source (Prev) then
1497 elsif Is_Entity_Name (Prev)
1498 and then Ekind (Etype (Prev)) = E_Anonymous_Access_Type
1502 elsif Nkind (Prev) = N_Allocator
1503 or else Nkind (Prev) = N_Attribute_Reference
1507 -- Suppress null checks when passing to access parameters
1508 -- of Java subprograms. (Should this be done for other
1509 -- foreign conventions as well ???)
1511 elsif Convention (Subp) = Convention_Java then
1517 Left_Opnd => Duplicate_Subexpr_No_Checks (Prev),
1518 Right_Opnd => Make_Null (Loc));
1519 Insert_Action (Prev,
1520 Make_Raise_Constraint_Error (Loc,
1522 Reason => CE_Access_Parameter_Is_Null));
1525 -- Perform appropriate validity checks on parameters that
1528 if Validity_Checks_On then
1529 if Ekind (Formal) = E_In_Parameter
1530 and then Validity_Check_In_Params
1532 -- If the actual is an indexed component of a packed
1533 -- type, it has not been expanded yet. It will be
1534 -- copied in the validity code that follows, and has
1535 -- to be expanded appropriately, so reanalyze it.
1537 if Nkind (Actual) = N_Indexed_Component then
1538 Set_Analyzed (Actual, False);
1541 Ensure_Valid (Actual);
1543 elsif Ekind (Formal) = E_In_Out_Parameter
1544 and then Validity_Check_In_Out_Params
1546 Ensure_Valid (Actual);
1550 -- For IN OUT and OUT parameters, ensure that subscripts are valid
1551 -- since this is a left side reference. We only do this for calls
1552 -- from the source program since we assume that compiler generated
1553 -- calls explicitly generate any required checks. We also need it
1554 -- only if we are doing standard validity checks, since clearly it
1555 -- is not needed if validity checks are off, and in subscript
1556 -- validity checking mode, all indexed components are checked with
1557 -- a call directly from Expand_N_Indexed_Component.
1559 if Comes_From_Source (N)
1560 and then Ekind (Formal) /= E_In_Parameter
1561 and then Validity_Checks_On
1562 and then Validity_Check_Default
1563 and then not Validity_Check_Subscripts
1565 Check_Valid_Lvalue_Subscripts (Actual);
1568 -- Mark any scalar OUT parameter that is a simple variable
1569 -- as no longer known to be valid (unless the type is always
1570 -- valid). This reflects the fact that if an OUT parameter
1571 -- is never set in a procedure, then it can become invalid
1572 -- on return from the procedure.
1574 if Ekind (Formal) = E_Out_Parameter
1575 and then Is_Entity_Name (Actual)
1576 and then Ekind (Entity (Actual)) = E_Variable
1577 and then not Is_Known_Valid (Etype (Actual))
1579 Set_Is_Known_Valid (Entity (Actual), False);
1582 -- For an OUT or IN OUT parameter of an access type, if the
1583 -- actual is an entity, then it is no longer known to be non-null.
1585 if Ekind (Formal) /= E_In_Parameter
1586 and then Is_Entity_Name (Actual)
1587 and then Is_Access_Type (Etype (Actual))
1589 Set_Is_Known_Non_Null (Entity (Actual), False);
1592 -- If the formal is class wide and the actual is an aggregate, force
1593 -- evaluation so that the back end who does not know about class-wide
1594 -- type, does not generate a temporary of the wrong size.
1596 if not Is_Class_Wide_Type (Etype (Formal)) then
1599 elsif Nkind (Actual) = N_Aggregate
1600 or else (Nkind (Actual) = N_Qualified_Expression
1601 and then Nkind (Expression (Actual)) = N_Aggregate)
1603 Force_Evaluation (Actual);
1606 -- In a remote call, if the formal is of a class-wide type, check
1607 -- that the actual meets the requirements described in E.4(18).
1610 and then Is_Class_Wide_Type (Etype (Formal))
1612 Insert_Action (Actual,
1613 Make_Implicit_If_Statement (N,
1616 Get_Remotely_Callable
1617 (Duplicate_Subexpr_Move_Checks (Actual))),
1618 Then_Statements => New_List (
1619 Make_Procedure_Call_Statement (Loc,
1620 New_Occurrence_Of (RTE
1621 (RE_Raise_Program_Error_For_E_4_18), Loc)))));
1624 Next_Actual (Actual);
1625 Next_Formal (Formal);
1628 -- If we are expanding a rhs of an assignement we need to check if
1629 -- tag propagation is needed. This code belongs theorically in Analyze
1630 -- Assignment but has to be done earlier (bottom-up) because the
1631 -- assignment might be transformed into a declaration for an uncons-
1632 -- trained value, if the expression is classwide.
1634 if Nkind (N) = N_Function_Call
1635 and then Is_Tag_Indeterminate (N)
1636 and then Is_Entity_Name (Name (N))
1639 Ass : Node_Id := Empty;
1642 if Nkind (Parent (N)) = N_Assignment_Statement then
1645 elsif Nkind (Parent (N)) = N_Qualified_Expression
1646 and then Nkind (Parent (Parent (N))) = N_Assignment_Statement
1648 Ass := Parent (Parent (N));
1652 and then Is_Class_Wide_Type (Etype (Name (Ass)))
1654 if Etype (N) /= Root_Type (Etype (Name (Ass))) then
1656 ("tag-indeterminate expression must have type&"
1657 & "('R'M 5.2 (6))", N, Root_Type (Etype (Name (Ass))));
1659 Propagate_Tag (Name (Ass), N);
1662 -- The call will be rewritten as a dispatching call, and
1663 -- expanded as such.
1670 -- Deals with Dispatch_Call if we still have a call, before expanding
1671 -- extra actuals since this will be done on the re-analysis of the
1672 -- dispatching call. Note that we do not try to shorten the actual
1673 -- list for a dispatching call, it would not make sense to do so.
1674 -- Expansion of dispatching calls is suppressed when Java_VM, because
1675 -- the JVM back end directly handles the generation of dispatching
1676 -- calls and would have to undo any expansion to an indirect call.
1678 if (Nkind (N) = N_Function_Call
1679 or else Nkind (N) = N_Procedure_Call_Statement)
1680 and then Present (Controlling_Argument (N))
1681 and then not Java_VM
1683 Expand_Dispatch_Call (N);
1685 -- The following return is worrisome. Is it really OK to
1686 -- skip all remaining processing in this procedure ???
1690 -- Similarly, expand calls to RCI subprograms on which pragma
1691 -- All_Calls_Remote applies. The rewriting will be reanalyzed
1692 -- later. Do this only when the call comes from source since we do
1693 -- not want such a rewritting to occur in expanded code.
1695 elsif Is_All_Remote_Call (N) then
1696 Expand_All_Calls_Remote_Subprogram_Call (N);
1698 -- Similarly, do not add extra actuals for an entry call whose entity
1699 -- is a protected procedure, or for an internal protected subprogram
1700 -- call, because it will be rewritten as a protected subprogram call
1701 -- and reanalyzed (see Expand_Protected_Subprogram_Call).
1703 elsif Is_Protected_Type (Scope (Subp))
1704 and then (Ekind (Subp) = E_Procedure
1705 or else Ekind (Subp) = E_Function)
1709 -- During that loop we gathered the extra actuals (the ones that
1710 -- correspond to Extra_Formals), so now they can be appended.
1713 while Is_Non_Empty_List (Extra_Actuals) loop
1714 Add_Actual_Parameter (Remove_Head (Extra_Actuals));
1718 if Ekind (Subp) = E_Procedure
1719 or else (Ekind (Subp) = E_Subprogram_Type
1720 and then Etype (Subp) = Standard_Void_Type)
1721 or else Is_Entry (Subp)
1723 Expand_Actuals (N, Subp);
1726 -- If the subprogram is a renaming, or if it is inherited, replace it
1727 -- in the call with the name of the actual subprogram being called.
1728 -- If this is a dispatching call, the run-time decides what to call.
1729 -- The Alias attribute does not apply to entries.
1731 if Nkind (N) /= N_Entry_Call_Statement
1732 and then No (Controlling_Argument (N))
1733 and then Present (Parent_Subp)
1735 if Present (Inherited_From_Formal (Subp)) then
1736 Parent_Subp := Inherited_From_Formal (Subp);
1738 while Present (Alias (Parent_Subp)) loop
1739 Parent_Subp := Alias (Parent_Subp);
1743 Set_Entity (Name (N), Parent_Subp);
1745 if Is_Abstract (Parent_Subp)
1746 and then not In_Instance
1749 ("cannot call abstract subprogram &!", Name (N), Parent_Subp);
1752 -- Add an explicit conversion for parameter of the derived type.
1753 -- This is only done for scalar and access in-parameters. Others
1754 -- have been expanded in expand_actuals.
1756 Formal := First_Formal (Subp);
1757 Parent_Formal := First_Formal (Parent_Subp);
1758 Actual := First_Actual (N);
1760 -- It is not clear that conversion is needed for intrinsic
1761 -- subprograms, but it certainly is for those that are user-
1762 -- defined, and that can be inherited on derivation, namely
1763 -- unchecked conversion and deallocation.
1764 -- General case needs study ???
1766 if not Is_Intrinsic_Subprogram (Parent_Subp)
1767 or else Is_Generic_Instance (Parent_Subp)
1769 while Present (Formal) loop
1771 if Etype (Formal) /= Etype (Parent_Formal)
1772 and then Is_Scalar_Type (Etype (Formal))
1773 and then Ekind (Formal) = E_In_Parameter
1774 and then not Raises_Constraint_Error (Actual)
1777 OK_Convert_To (Etype (Parent_Formal),
1778 Relocate_Node (Actual)));
1781 Resolve (Actual, Etype (Parent_Formal));
1782 Enable_Range_Check (Actual);
1784 elsif Is_Access_Type (Etype (Formal))
1785 and then Base_Type (Etype (Parent_Formal))
1786 /= Base_Type (Etype (Actual))
1788 if Ekind (Formal) /= E_In_Parameter then
1790 Convert_To (Etype (Parent_Formal),
1791 Relocate_Node (Actual)));
1794 Resolve (Actual, Etype (Parent_Formal));
1797 Ekind (Etype (Parent_Formal)) = E_Anonymous_Access_Type
1798 and then Designated_Type (Etype (Parent_Formal))
1800 Designated_Type (Etype (Actual))
1801 and then not Is_Controlling_Formal (Formal)
1803 -- This unchecked conversion is not necessary unless
1804 -- inlining is enabled, because in that case the type
1805 -- mismatch may become visible in the body about to be
1809 Unchecked_Convert_To (Etype (Parent_Formal),
1810 Relocate_Node (Actual)));
1813 Resolve (Actual, Etype (Parent_Formal));
1817 Next_Formal (Formal);
1818 Next_Formal (Parent_Formal);
1819 Next_Actual (Actual);
1824 Subp := Parent_Subp;
1827 if Is_RTE (Subp, RE_Abort_Task) then
1828 Check_Restriction (No_Abort_Statements, N);
1831 if Nkind (Name (N)) = N_Explicit_Dereference then
1833 -- Handle case of access to protected subprogram type
1835 if Ekind (Base_Type (Etype (Prefix (Name (N))))) =
1836 E_Access_Protected_Subprogram_Type
1838 -- If this is a call through an access to protected operation,
1839 -- the prefix has the form (object'address, operation'access).
1840 -- Rewrite as a for other protected calls: the object is the
1841 -- first parameter of the list of actuals.
1848 Ptr : constant Node_Id := Prefix (Name (N));
1850 T : constant Entity_Id :=
1851 Equivalent_Type (Base_Type (Etype (Ptr)));
1853 D_T : constant Entity_Id :=
1854 Designated_Type (Base_Type (Etype (Ptr)));
1857 Obj := Make_Selected_Component (Loc,
1858 Prefix => Unchecked_Convert_To (T, Ptr),
1859 Selector_Name => New_Occurrence_Of (First_Entity (T), Loc));
1861 Nam := Make_Selected_Component (Loc,
1862 Prefix => Unchecked_Convert_To (T, Ptr),
1863 Selector_Name => New_Occurrence_Of (
1864 Next_Entity (First_Entity (T)), Loc));
1866 Nam := Make_Explicit_Dereference (Loc, Nam);
1868 if Present (Parameter_Associations (N)) then
1869 Parm := Parameter_Associations (N);
1874 Prepend (Obj, Parm);
1876 if Etype (D_T) = Standard_Void_Type then
1877 Call := Make_Procedure_Call_Statement (Loc,
1879 Parameter_Associations => Parm);
1881 Call := Make_Function_Call (Loc,
1883 Parameter_Associations => Parm);
1886 Set_First_Named_Actual (Call, First_Named_Actual (N));
1887 Set_Etype (Call, Etype (D_T));
1889 -- We do not re-analyze the call to avoid infinite recursion.
1890 -- We analyze separately the prefix and the object, and set
1891 -- the checks on the prefix that would otherwise be emitted
1892 -- when resolving a call.
1896 Apply_Access_Check (Nam);
1903 -- If this is a call to an intrinsic subprogram, then perform the
1904 -- appropriate expansion to the corresponding tree node and we
1905 -- are all done (since after that the call is gone!)
1907 if Is_Intrinsic_Subprogram (Subp) then
1908 Expand_Intrinsic_Call (N, Subp);
1912 if Ekind (Subp) = E_Function
1913 or else Ekind (Subp) = E_Procedure
1915 if Is_Inlined (Subp) then
1919 Must_Inline : Boolean := False;
1920 Spec : constant Node_Id := Unit_Declaration_Node (Subp);
1921 Scop : constant Entity_Id := Scope (Subp);
1924 -- Verify that the body to inline has already been seen,
1925 -- and that if the body is in the current unit the inlining
1926 -- does not occur earlier. This avoids order-of-elaboration
1927 -- problems in gigi.
1930 or else Nkind (Spec) /= N_Subprogram_Declaration
1931 or else No (Body_To_Inline (Spec))
1933 Must_Inline := False;
1935 -- If this an inherited function that returns a private
1936 -- type, do not inline if the full view is an unconstrained
1937 -- array, because such calls cannot be inlined.
1939 elsif Present (Orig_Subp)
1940 and then Is_Array_Type (Etype (Orig_Subp))
1941 and then not Is_Constrained (Etype (Orig_Subp))
1943 Must_Inline := False;
1945 -- If the subprogram comes from an instance in the same
1946 -- unit, and the instance is not yet frozen, inlining might
1947 -- trigger order-of-elaboration problems in gigi.
1949 elsif Is_Generic_Instance (Scop)
1950 and then Present (Freeze_Node (Scop))
1951 and then not Analyzed (Freeze_Node (Scop))
1953 Must_Inline := False;
1956 Bod := Body_To_Inline (Spec);
1958 if (In_Extended_Main_Code_Unit (N)
1959 or else In_Extended_Main_Code_Unit (Parent (N))
1960 or else Is_Always_Inlined (Subp))
1961 and then (not In_Same_Extended_Unit (Sloc (Bod), Loc)
1963 Earlier_In_Extended_Unit (Sloc (Bod), Loc))
1965 Must_Inline := True;
1967 -- If we are compiling a package body that is not the main
1968 -- unit, it must be for inlining/instantiation purposes,
1969 -- in which case we inline the call to insure that the same
1970 -- temporaries are generated when compiling the body by
1971 -- itself. Otherwise link errors can occur.
1973 elsif not (In_Extended_Main_Code_Unit (N))
1974 and then In_Package_Body
1976 Must_Inline := True;
1981 Expand_Inlined_Call (N, Subp, Orig_Subp);
1984 -- Let the back end handle it
1986 Add_Inlined_Body (Subp);
1988 if Front_End_Inlining
1989 and then Nkind (Spec) = N_Subprogram_Declaration
1990 and then (In_Extended_Main_Code_Unit (N))
1991 and then No (Body_To_Inline (Spec))
1992 and then not Has_Completion (Subp)
1993 and then In_Same_Extended_Unit (Sloc (Spec), Loc)
1996 ("cannot inline& (body not seen yet)?",
2004 -- Check for a protected subprogram. This is either an intra-object
2005 -- call, or a protected function call. Protected procedure calls are
2006 -- rewritten as entry calls and handled accordingly.
2008 Scop := Scope (Subp);
2010 if Nkind (N) /= N_Entry_Call_Statement
2011 and then Is_Protected_Type (Scop)
2013 -- If the call is an internal one, it is rewritten as a call to
2014 -- to the corresponding unprotected subprogram.
2016 Expand_Protected_Subprogram_Call (N, Subp, Scop);
2019 -- Functions returning controlled objects need special attention
2021 if Controlled_Type (Etype (Subp))
2022 and then not Is_Return_By_Reference_Type (Etype (Subp))
2024 Expand_Ctrl_Function_Call (N);
2027 -- Test for First_Optional_Parameter, and if so, truncate parameter
2028 -- list if there are optional parameters at the trailing end.
2029 -- Note we never delete procedures for call via a pointer.
2031 if (Ekind (Subp) = E_Procedure or else Ekind (Subp) = E_Function)
2032 and then Present (First_Optional_Parameter (Subp))
2035 Last_Keep_Arg : Node_Id;
2038 -- Last_Keep_Arg will hold the last actual that should be
2039 -- retained. If it remains empty at the end, it means that
2040 -- all parameters are optional.
2042 Last_Keep_Arg := Empty;
2044 -- Find first optional parameter, must be present since we
2045 -- checked the validity of the parameter before setting it.
2047 Formal := First_Formal (Subp);
2048 Actual := First_Actual (N);
2049 while Formal /= First_Optional_Parameter (Subp) loop
2050 Last_Keep_Arg := Actual;
2051 Next_Formal (Formal);
2052 Next_Actual (Actual);
2055 -- We have Formal and Actual pointing to the first potentially
2056 -- droppable argument. We can drop all the trailing arguments
2057 -- whose actual matches the default. Note that we know that all
2058 -- remaining formals have defaults, because we checked that this
2059 -- requirement was met before setting First_Optional_Parameter.
2061 -- We use Fully_Conformant_Expressions to check for identity
2062 -- between formals and actuals, which may miss some cases, but
2063 -- on the other hand, this is only an optimization (if we fail
2064 -- to truncate a parameter it does not affect functionality).
2065 -- So if the default is 3 and the actual is 1+2, we consider
2066 -- them unequal, which hardly seems worrisome.
2068 while Present (Formal) loop
2069 if not Fully_Conformant_Expressions
2070 (Actual, Default_Value (Formal))
2072 Last_Keep_Arg := Actual;
2075 Next_Formal (Formal);
2076 Next_Actual (Actual);
2079 -- If no arguments, delete entire list, this is the easy case
2081 if No (Last_Keep_Arg) then
2082 while Is_Non_Empty_List (Parameter_Associations (N)) loop
2083 Delete_Tree (Remove_Head (Parameter_Associations (N)));
2086 Set_Parameter_Associations (N, No_List);
2087 Set_First_Named_Actual (N, Empty);
2089 -- Case where at the last retained argument is positional. This
2090 -- is also an easy case, since the retained arguments are already
2091 -- in the right form, and we don't need to worry about the order
2092 -- of arguments that get eliminated.
2094 elsif Is_List_Member (Last_Keep_Arg) then
2095 while Present (Next (Last_Keep_Arg)) loop
2096 Delete_Tree (Remove_Next (Last_Keep_Arg));
2099 Set_First_Named_Actual (N, Empty);
2101 -- This is the annoying case where the last retained argument
2102 -- is a named parameter. Since the original arguments are not
2103 -- in declaration order, we may have to delete some fairly
2104 -- random collection of arguments.
2112 pragma Warnings (Off, Discard);
2115 -- First step, remove all the named parameters from the
2116 -- list (they are still chained using First_Named_Actual
2117 -- and Next_Named_Actual, so we have not lost them!)
2119 Temp := First (Parameter_Associations (N));
2121 -- Case of all parameters named, remove them all
2123 if Nkind (Temp) = N_Parameter_Association then
2124 while Is_Non_Empty_List (Parameter_Associations (N)) loop
2125 Temp := Remove_Head (Parameter_Associations (N));
2128 -- Case of mixed positional/named, remove named parameters
2131 while Nkind (Next (Temp)) /= N_Parameter_Association loop
2135 while Present (Next (Temp)) loop
2136 Discard := Remove_Next (Temp);
2140 -- Now we loop through the named parameters, till we get
2141 -- to the last one to be retained, adding them to the list.
2142 -- Note that the Next_Named_Actual list does not need to be
2143 -- touched since we are only reordering them on the actual
2144 -- parameter association list.
2146 Passoc := Parent (First_Named_Actual (N));
2148 Temp := Relocate_Node (Passoc);
2150 (Parameter_Associations (N), Temp);
2152 Last_Keep_Arg = Explicit_Actual_Parameter (Passoc);
2153 Passoc := Parent (Next_Named_Actual (Passoc));
2156 Set_Next_Named_Actual (Temp, Empty);
2159 Temp := Next_Named_Actual (Passoc);
2160 exit when No (Temp);
2161 Set_Next_Named_Actual
2162 (Passoc, Next_Named_Actual (Parent (Temp)));
2171 --------------------------
2172 -- Expand_Inlined_Call --
2173 --------------------------
2175 procedure Expand_Inlined_Call
2178 Orig_Subp : Entity_Id)
2180 Loc : constant Source_Ptr := Sloc (N);
2181 Is_Predef : constant Boolean :=
2182 Is_Predefined_File_Name
2183 (Unit_File_Name (Get_Source_Unit (Subp)));
2184 Orig_Bod : constant Node_Id :=
2185 Body_To_Inline (Unit_Declaration_Node (Subp));
2190 Exit_Lab : Entity_Id := Empty;
2197 Ret_Type : Entity_Id;
2200 Temp_Typ : Entity_Id;
2202 procedure Make_Exit_Label;
2203 -- Build declaration for exit label to be used in Return statements.
2205 function Process_Formals (N : Node_Id) return Traverse_Result;
2206 -- Replace occurrence of a formal with the corresponding actual, or
2207 -- the thunk generated for it.
2209 function Process_Sloc (Nod : Node_Id) return Traverse_Result;
2210 -- If the call being expanded is that of an internal subprogram,
2211 -- set the sloc of the generated block to that of the call itself,
2212 -- so that the expansion is skipped by the -next- command in gdb.
2213 -- Same processing for a subprogram in a predefined file, e.g.
2214 -- Ada.Tags. If Debug_Generated_Code is true, suppress this change
2215 -- to simplify our own development.
2217 procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id);
2218 -- If the function body is a single expression, replace call with
2219 -- expression, else insert block appropriately.
2221 procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id);
2222 -- If procedure body has no local variables, inline body without
2223 -- creating block, otherwise rewrite call with block.
2225 ---------------------
2226 -- Make_Exit_Label --
2227 ---------------------
2229 procedure Make_Exit_Label is
2231 -- Create exit label for subprogram, if one doesn't exist yet.
2233 if No (Exit_Lab) then
2234 Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L'));
2236 Make_Defining_Identifier (Loc, Chars (Lab_Id)));
2237 Exit_Lab := Make_Label (Loc, Lab_Id);
2240 Make_Implicit_Label_Declaration (Loc,
2241 Defining_Identifier => Entity (Lab_Id),
2242 Label_Construct => Exit_Lab);
2244 end Make_Exit_Label;
2246 ---------------------
2247 -- Process_Formals --
2248 ---------------------
2250 function Process_Formals (N : Node_Id) return Traverse_Result is
2256 if Is_Entity_Name (N)
2257 and then Present (Entity (N))
2262 and then Scope (E) = Subp
2264 A := Renamed_Object (E);
2266 if Is_Entity_Name (A) then
2267 Rewrite (N, New_Occurrence_Of (Entity (A), Loc));
2269 elsif Nkind (A) = N_Defining_Identifier then
2270 Rewrite (N, New_Occurrence_Of (A, Loc));
2272 else -- numeric literal
2273 Rewrite (N, New_Copy (A));
2279 elsif Nkind (N) = N_Return_Statement then
2281 if No (Expression (N)) then
2283 Rewrite (N, Make_Goto_Statement (Loc,
2284 Name => New_Copy (Lab_Id)));
2287 if Nkind (Parent (N)) = N_Handled_Sequence_Of_Statements
2288 and then Nkind (Parent (Parent (N))) = N_Subprogram_Body
2290 -- Function body is a single expression. No need for
2296 Num_Ret := Num_Ret + 1;
2300 -- Because of the presence of private types, the views of the
2301 -- expression and the context may be different, so place an
2302 -- unchecked conversion to the context type to avoid spurious
2303 -- errors, eg. when the expression is a numeric literal and
2304 -- the context is private. If the expression is an aggregate,
2305 -- use a qualified expression, because an aggregate is not a
2306 -- legal argument of a conversion.
2308 if Nkind (Expression (N)) = N_Aggregate
2309 or else Nkind (Expression (N)) = N_Null
2312 Make_Qualified_Expression (Sloc (N),
2313 Subtype_Mark => New_Occurrence_Of (Ret_Type, Sloc (N)),
2314 Expression => Relocate_Node (Expression (N)));
2317 Unchecked_Convert_To
2318 (Ret_Type, Relocate_Node (Expression (N)));
2321 if Nkind (Targ) = N_Defining_Identifier then
2323 Make_Assignment_Statement (Loc,
2324 Name => New_Occurrence_Of (Targ, Loc),
2325 Expression => Ret));
2328 Make_Assignment_Statement (Loc,
2329 Name => New_Copy (Targ),
2330 Expression => Ret));
2333 Set_Assignment_OK (Name (N));
2335 if Present (Exit_Lab) then
2337 Make_Goto_Statement (Loc,
2338 Name => New_Copy (Lab_Id)));
2344 -- Remove pragma Unreferenced since it may refer to formals that
2345 -- are not visible in the inlined body, and in any case we will
2346 -- not be posting warnings on the inlined body so it is unneeded.
2348 elsif Nkind (N) = N_Pragma
2349 and then Chars (N) = Name_Unreferenced
2351 Rewrite (N, Make_Null_Statement (Sloc (N)));
2357 end Process_Formals;
2359 procedure Replace_Formals is new Traverse_Proc (Process_Formals);
2365 function Process_Sloc (Nod : Node_Id) return Traverse_Result is
2367 if not Debug_Generated_Code then
2368 Set_Sloc (Nod, Sloc (N));
2369 Set_Comes_From_Source (Nod, False);
2375 procedure Reset_Slocs is new Traverse_Proc (Process_Sloc);
2377 ---------------------------
2378 -- Rewrite_Function_Call --
2379 ---------------------------
2381 procedure Rewrite_Function_Call (N : Node_Id; Blk : Node_Id) is
2382 HSS : constant Node_Id := Handled_Statement_Sequence (Blk);
2383 Fst : constant Node_Id := First (Statements (HSS));
2386 -- Optimize simple case: function body is a single return statement,
2387 -- which has been expanded into an assignment.
2389 if Is_Empty_List (Declarations (Blk))
2390 and then Nkind (Fst) = N_Assignment_Statement
2391 and then No (Next (Fst))
2394 -- The function call may have been rewritten as the temporary
2395 -- that holds the result of the call, in which case remove the
2396 -- now useless declaration.
2398 if Nkind (N) = N_Identifier
2399 and then Nkind (Parent (Entity (N))) = N_Object_Declaration
2401 Rewrite (Parent (Entity (N)), Make_Null_Statement (Loc));
2404 Rewrite (N, Expression (Fst));
2406 elsif Nkind (N) = N_Identifier
2407 and then Nkind (Parent (Entity (N))) = N_Object_Declaration
2410 -- The block assigns the result of the call to the temporary.
2412 Insert_After (Parent (Entity (N)), Blk);
2414 elsif Nkind (Parent (N)) = N_Assignment_Statement
2415 and then Is_Entity_Name (Name (Parent (N)))
2418 -- Replace assignment with the block
2420 Rewrite (Parent (N), Blk);
2422 elsif Nkind (Parent (N)) = N_Object_Declaration then
2423 Set_Expression (Parent (N), Empty);
2424 Insert_After (Parent (N), Blk);
2426 end Rewrite_Function_Call;
2428 ----------------------------
2429 -- Rewrite_Procedure_Call --
2430 ----------------------------
2432 procedure Rewrite_Procedure_Call (N : Node_Id; Blk : Node_Id) is
2433 HSS : constant Node_Id := Handled_Statement_Sequence (Blk);
2436 if Is_Empty_List (Declarations (Blk)) then
2437 Insert_List_After (N, Statements (HSS));
2438 Rewrite (N, Make_Null_Statement (Loc));
2442 end Rewrite_Procedure_Call;
2444 -- Start of processing for Expand_Inlined_Call
2447 -- Check for special case of To_Address call, and if so, just
2448 -- do an unchecked conversion instead of expanding the call.
2449 -- Not only is this more efficient, but it also avoids a
2450 -- problem with order of elaboration when address clauses
2451 -- are inlined (address expr elaborated at wrong point).
2453 if Subp = RTE (RE_To_Address) then
2455 Unchecked_Convert_To
2457 Relocate_Node (First_Actual (N))));
2461 if Nkind (Orig_Bod) = N_Defining_Identifier then
2463 -- Subprogram is a renaming_as_body. Calls appearing after the
2464 -- renaming can be replaced with calls to the renamed entity
2465 -- directly, because the subprograms are subtype conformant.
2467 Set_Name (N, New_Occurrence_Of (Orig_Bod, Loc));
2471 -- Use generic machinery to copy body of inlined subprogram, as if it
2472 -- were an instantiation, resetting source locations appropriately, so
2473 -- that nested inlined calls appear in the main unit.
2475 Save_Env (Subp, Empty);
2476 Set_Copied_Sloc_For_Inlined_Body (N, Defining_Entity (Orig_Bod));
2478 Bod := Copy_Generic_Node (Orig_Bod, Empty, Instantiating => True);
2480 Make_Block_Statement (Loc,
2481 Declarations => Declarations (Bod),
2482 Handled_Statement_Sequence => Handled_Statement_Sequence (Bod));
2484 if No (Declarations (Bod)) then
2485 Set_Declarations (Blk, New_List);
2488 -- If this is a derived function, establish the proper return type.
2490 if Present (Orig_Subp)
2491 and then Orig_Subp /= Subp
2493 Ret_Type := Etype (Orig_Subp);
2495 Ret_Type := Etype (Subp);
2498 F := First_Formal (Subp);
2499 A := First_Actual (N);
2501 -- Create temporaries for the actuals that are expressions, or that
2502 -- are scalars and require copying to preserve semantics.
2504 while Present (F) loop
2505 if Present (Renamed_Object (F)) then
2506 Error_Msg_N (" cannot inline call to recursive subprogram", N);
2510 -- If the argument may be a controlling argument in a call within
2511 -- the inlined body, we must preserve its classwide nature to
2512 -- insure that dynamic dispatching take place subsequently.
2513 -- If the formal has a constraint it must be preserved to retain
2514 -- the semantics of the body.
2516 if Is_Class_Wide_Type (Etype (F))
2517 or else (Is_Access_Type (Etype (F))
2519 Is_Class_Wide_Type (Designated_Type (Etype (F))))
2521 Temp_Typ := Etype (F);
2523 elsif Base_Type (Etype (F)) = Base_Type (Etype (A))
2524 and then Etype (F) /= Base_Type (Etype (F))
2526 Temp_Typ := Etype (F);
2529 Temp_Typ := Etype (A);
2532 -- If the actual is a simple name or a literal, no need to
2533 -- create a temporary, object can be used directly.
2535 if (Is_Entity_Name (A)
2537 (not Is_Scalar_Type (Etype (A))
2538 or else Ekind (Entity (A)) = E_Enumeration_Literal))
2540 or else Nkind (A) = N_Real_Literal
2541 or else Nkind (A) = N_Integer_Literal
2542 or else Nkind (A) = N_Character_Literal
2544 if Etype (F) /= Etype (A) then
2546 (F, Unchecked_Convert_To (Etype (F), Relocate_Node (A)));
2548 Set_Renamed_Object (F, A);
2553 Make_Defining_Identifier (Loc,
2554 Chars => New_Internal_Name ('C'));
2556 -- If the actual for an in/in-out parameter is a view conversion,
2557 -- make it into an unchecked conversion, given that an untagged
2558 -- type conversion is not a proper object for a renaming.
2560 -- In-out conversions that involve real conversions have already
2561 -- been transformed in Expand_Actuals.
2563 if Nkind (A) = N_Type_Conversion
2564 and then Ekind (F) /= E_In_Parameter
2566 New_A := Make_Unchecked_Type_Conversion (Loc,
2567 Subtype_Mark => New_Occurrence_Of (Etype (F), Loc),
2568 Expression => Relocate_Node (Expression (A)));
2570 elsif Etype (F) /= Etype (A) then
2571 New_A := Unchecked_Convert_To (Etype (F), Relocate_Node (A));
2572 Temp_Typ := Etype (F);
2575 New_A := Relocate_Node (A);
2578 Set_Sloc (New_A, Sloc (N));
2580 if Ekind (F) = E_In_Parameter
2581 and then not Is_Limited_Type (Etype (A))
2584 Make_Object_Declaration (Loc,
2585 Defining_Identifier => Temp,
2586 Constant_Present => True,
2587 Object_Definition => New_Occurrence_Of (Temp_Typ, Loc),
2588 Expression => New_A);
2591 Make_Object_Renaming_Declaration (Loc,
2592 Defining_Identifier => Temp,
2593 Subtype_Mark => New_Occurrence_Of (Temp_Typ, Loc),
2597 Prepend (Decl, Declarations (Blk));
2598 Set_Renamed_Object (F, Temp);
2605 -- Establish target of function call. If context is not assignment or
2606 -- declaration, create a temporary as a target. The declaration for
2607 -- the temporary may be subsequently optimized away if the body is a
2608 -- single expression, or if the left-hand side of the assignment is
2611 if Ekind (Subp) = E_Function then
2612 if Nkind (Parent (N)) = N_Assignment_Statement
2613 and then Is_Entity_Name (Name (Parent (N)))
2615 Targ := Name (Parent (N));
2618 -- Replace call with temporary, and create its declaration.
2621 Make_Defining_Identifier (Loc, New_Internal_Name ('C'));
2624 Make_Object_Declaration (Loc,
2625 Defining_Identifier => Temp,
2626 Object_Definition =>
2627 New_Occurrence_Of (Ret_Type, Loc));
2629 Set_No_Initialization (Decl);
2630 Insert_Action (N, Decl);
2631 Rewrite (N, New_Occurrence_Of (Temp, Loc));
2636 -- Traverse the tree and replace formals with actuals or their thunks.
2637 -- Attach block to tree before analysis and rewriting.
2639 Replace_Formals (Blk);
2640 Set_Parent (Blk, N);
2642 if not Comes_From_Source (Subp)
2648 if Present (Exit_Lab) then
2650 -- If the body was a single expression, the single return statement
2651 -- and the corresponding label are useless.
2655 Nkind (Last (Statements (Handled_Statement_Sequence (Blk)))) =
2658 Remove (Last (Statements (Handled_Statement_Sequence (Blk))));
2660 Append (Lab_Decl, (Declarations (Blk)));
2661 Append (Exit_Lab, Statements (Handled_Statement_Sequence (Blk)));
2665 -- Analyze Blk with In_Inlined_Body set, to avoid spurious errors on
2666 -- conflicting private views that Gigi would ignore. If this is a
2667 -- predefined unit, analyze with checks off, as is done in the non-
2668 -- inlined run-time units.
2671 I_Flag : constant Boolean := In_Inlined_Body;
2674 In_Inlined_Body := True;
2678 Style : constant Boolean := Style_Check;
2680 Style_Check := False;
2681 Analyze (Blk, Suppress => All_Checks);
2682 Style_Check := Style;
2689 In_Inlined_Body := I_Flag;
2692 if Ekind (Subp) = E_Procedure then
2693 Rewrite_Procedure_Call (N, Blk);
2695 Rewrite_Function_Call (N, Blk);
2700 -- Cleanup mapping between formals and actuals, for other expansions.
2702 F := First_Formal (Subp);
2704 while Present (F) loop
2705 Set_Renamed_Object (F, Empty);
2708 end Expand_Inlined_Call;
2710 ----------------------------
2711 -- Expand_N_Function_Call --
2712 ----------------------------
2714 procedure Expand_N_Function_Call (N : Node_Id) is
2715 Typ : constant Entity_Id := Etype (N);
2717 function Returned_By_Reference return Boolean;
2718 -- If the return type is returned through the secondary stack. that is
2719 -- by reference, we don't want to create a temp to force stack checking.
2721 function Returned_By_Reference return Boolean is
2722 S : Entity_Id := Current_Scope;
2725 if Is_Return_By_Reference_Type (Typ) then
2728 elsif Nkind (Parent (N)) /= N_Return_Statement then
2731 elsif Requires_Transient_Scope (Typ) then
2733 -- Verify that the return type of the enclosing function has
2734 -- the same constrained status as that of the expression.
2736 while Ekind (S) /= E_Function loop
2740 return Is_Constrained (Typ) = Is_Constrained (Etype (S));
2744 end Returned_By_Reference;
2746 -- Start of processing for Expand_N_Function_Call
2749 -- A special check. If stack checking is enabled, and the return type
2750 -- might generate a large temporary, and the call is not the right
2751 -- side of an assignment, then generate an explicit temporary. We do
2752 -- this because otherwise gigi may generate a large temporary on the
2753 -- fly and this can cause trouble with stack checking.
2755 if May_Generate_Large_Temp (Typ)
2756 and then Nkind (Parent (N)) /= N_Assignment_Statement
2758 (Nkind (Parent (N)) /= N_Qualified_Expression
2759 or else Nkind (Parent (Parent (N))) /= N_Assignment_Statement)
2761 (Nkind (Parent (N)) /= N_Object_Declaration
2762 or else Expression (Parent (N)) /= N)
2763 and then not Returned_By_Reference
2765 -- Note: it might be thought that it would be OK to use a call to
2766 -- Force_Evaluation here, but that's not good enough, because that
2767 -- results in a 'Reference construct that may still need a temporary.
2770 Loc : constant Source_Ptr := Sloc (N);
2771 Temp_Obj : constant Entity_Id :=
2772 Make_Defining_Identifier (Loc,
2773 Chars => New_Internal_Name ('F'));
2774 Temp_Typ : Entity_Id := Typ;
2781 if Is_Tagged_Type (Typ)
2782 and then Present (Controlling_Argument (N))
2784 if Nkind (Parent (N)) /= N_Procedure_Call_Statement
2785 and then Nkind (Parent (N)) /= N_Function_Call
2787 -- If this is a tag-indeterminate call, the object must
2790 if Is_Tag_Indeterminate (N) then
2791 Temp_Typ := Class_Wide_Type (Typ);
2795 -- If this is a dispatching call that is itself the
2796 -- controlling argument of an enclosing call, the nominal
2797 -- subtype of the object that replaces it must be classwide,
2798 -- so that dispatching will take place properly. If it is
2799 -- not a controlling argument, the object is not classwide.
2801 Proc := Entity (Name (Parent (N)));
2802 F := First_Formal (Proc);
2803 A := First_Actual (Parent (N));
2810 if Is_Controlling_Formal (F) then
2811 Temp_Typ := Class_Wide_Type (Typ);
2817 Make_Object_Declaration (Loc,
2818 Defining_Identifier => Temp_Obj,
2819 Object_Definition => New_Occurrence_Of (Temp_Typ, Loc),
2820 Constant_Present => True,
2821 Expression => Relocate_Node (N));
2822 Set_Assignment_OK (Decl);
2824 Insert_Actions (N, New_List (Decl));
2825 Rewrite (N, New_Occurrence_Of (Temp_Obj, Loc));
2828 -- Normal case, expand the call
2833 end Expand_N_Function_Call;
2835 ---------------------------------------
2836 -- Expand_N_Procedure_Call_Statement --
2837 ---------------------------------------
2839 procedure Expand_N_Procedure_Call_Statement (N : Node_Id) is
2842 end Expand_N_Procedure_Call_Statement;
2844 ------------------------------
2845 -- Expand_N_Subprogram_Body --
2846 ------------------------------
2848 -- Add poll call if ATC polling is enabled
2850 -- Add return statement if last statement in body is not a return
2851 -- statement (this makes things easier on Gigi which does not want
2852 -- to have to handle a missing return).
2854 -- Add call to Activate_Tasks if body is a task activator
2856 -- Deal with possible detection of infinite recursion
2858 -- Eliminate body completely if convention stubbed
2860 -- Encode entity names within body, since we will not need to reference
2861 -- these entities any longer in the front end.
2863 -- Initialize scalar out parameters if Initialize/Normalize_Scalars
2865 -- Reset Pure indication if any parameter has root type System.Address
2869 procedure Expand_N_Subprogram_Body (N : Node_Id) is
2870 Loc : constant Source_Ptr := Sloc (N);
2871 H : constant Node_Id := Handled_Statement_Sequence (N);
2872 Body_Id : Entity_Id;
2873 Spec_Id : Entity_Id;
2880 procedure Add_Return (S : List_Id);
2881 -- Append a return statement to the statement sequence S if the last
2882 -- statement is not already a return or a goto statement. Note that
2883 -- the latter test is not critical, it does not matter if we add a
2884 -- few extra returns, since they get eliminated anyway later on.
2886 procedure Expand_Thread_Body;
2887 -- Perform required expansion of a thread body
2893 procedure Add_Return (S : List_Id) is
2895 if not Is_Transfer (Last (S)) then
2897 -- The source location for the return is the end label
2898 -- of the procedure in all cases. This is a bit odd when
2899 -- there are exception handlers, but not much else we can do.
2901 Append_To (S, Make_Return_Statement (Sloc (End_Label (H))));
2905 ------------------------
2906 -- Expand_Thread_Body --
2907 ------------------------
2909 -- The required expansion of a thread body is as follows
2911 -- procedure <thread body procedure name> is
2913 -- _Secondary_Stack : aliased
2914 -- Storage_Elements.Storage_Array
2915 -- (1 .. Storage_Offset (Sec_Stack_Size));
2916 -- for _Secondary_Stack'Alignment use Standard'Maximum_Alignment;
2918 -- _Process_ATSD : aliased System.Threads.ATSD;
2921 -- System.Threads.Thread_Body_Enter;
2922 -- (_Secondary_Stack'Address,
2923 -- _Secondary_Stack'Length,
2924 -- _Process_ATSD'Address);
2927 -- <user declarations>
2929 -- <user statements>
2930 -- <user exception handlers>
2933 -- System.Threads.Thread_Body_Leave;
2936 -- when E : others =>
2937 -- System.Threads.Thread_Body_Exceptional_Exit (E);
2940 -- Note the exception handler is omitted if pragma Restriction
2941 -- No_Exception_Handlers is currently active.
2943 procedure Expand_Thread_Body is
2944 User_Decls : constant List_Id := Declarations (N);
2945 Sec_Stack_Len : Node_Id;
2947 TB_Pragma : constant Node_Id :=
2948 Get_Rep_Pragma (Spec_Id, Name_Thread_Body);
2951 Ent_ATSD : Entity_Id;
2955 Decl_ATSD : Node_Id;
2957 Excep_Handlers : List_Id;
2960 New_Scope (Spec_Id);
2962 -- Get proper setting for secondary stack size
2964 if List_Length (Pragma_Argument_Associations (TB_Pragma)) = 2 then
2966 Expression (Last (Pragma_Argument_Associations (TB_Pragma)));
2969 New_Occurrence_Of (RTE (RE_Default_Secondary_Stack_Size), Loc);
2972 Sec_Stack_Len := Convert_To (RTE (RE_Storage_Offset), Sec_Stack_Len);
2974 -- Build and set declarations for the wrapped thread body
2976 Ent_SS := Make_Defining_Identifier (Loc, Name_uSecondary_Stack);
2977 Ent_ATSD := Make_Defining_Identifier (Loc, Name_uProcess_ATSD);
2980 Make_Object_Declaration (Loc,
2981 Defining_Identifier => Ent_SS,
2982 Aliased_Present => True,
2983 Object_Definition =>
2984 Make_Subtype_Indication (Loc,
2986 New_Occurrence_Of (RTE (RE_Storage_Array), Loc),
2988 Make_Index_Or_Discriminant_Constraint (Loc,
2989 Constraints => New_List (
2991 Low_Bound => Make_Integer_Literal (Loc, 1),
2992 High_Bound => Sec_Stack_Len)))));
2995 Make_Object_Declaration (Loc,
2996 Defining_Identifier => Ent_ATSD,
2997 Aliased_Present => True,
2998 Object_Definition => New_Occurrence_Of (RTE (RE_ATSD), Loc));
3000 Set_Declarations (N, New_List (Decl_SS, Decl_ATSD));
3002 Analyze (Decl_ATSD);
3003 Set_Alignment (Ent_SS, UI_From_Int (Maximum_Alignment));
3005 -- Create new exception handler
3007 if Restrictions (No_Exception_Handlers) then
3008 Excep_Handlers := No_List;
3011 Check_Restriction (No_Exception_Handlers, N);
3013 Ent_EO := Make_Defining_Identifier (Loc, Name_uE);
3015 Excep_Handlers := New_List (
3016 Make_Exception_Handler (Loc,
3017 Choice_Parameter => Ent_EO,
3018 Exception_Choices => New_List (
3019 Make_Others_Choice (Loc)),
3020 Statements => New_List (
3021 Make_Procedure_Call_Statement (Loc,
3024 (RTE (RE_Thread_Body_Exceptional_Exit), Loc),
3025 Parameter_Associations => New_List (
3026 New_Occurrence_Of (Ent_EO, Loc))))));
3029 -- Now build new handled statement sequence and analyze it
3031 Set_Handled_Statement_Sequence (N,
3032 Make_Handled_Sequence_Of_Statements (Loc,
3033 Statements => New_List (
3035 Make_Procedure_Call_Statement (Loc,
3036 Name => New_Occurrence_Of (RTE (RE_Thread_Body_Enter), Loc),
3037 Parameter_Associations => New_List (
3039 Make_Attribute_Reference (Loc,
3040 Prefix => New_Occurrence_Of (Ent_SS, Loc),
3041 Attribute_Name => Name_Address),
3043 Make_Attribute_Reference (Loc,
3044 Prefix => New_Occurrence_Of (Ent_SS, Loc),
3045 Attribute_Name => Name_Length),
3047 Make_Attribute_Reference (Loc,
3048 Prefix => New_Occurrence_Of (Ent_ATSD, Loc),
3049 Attribute_Name => Name_Address))),
3051 Make_Block_Statement (Loc,
3052 Declarations => User_Decls,
3053 Handled_Statement_Sequence => H),
3055 Make_Procedure_Call_Statement (Loc,
3056 Name => New_Occurrence_Of (RTE (RE_Thread_Body_Leave), Loc))),
3058 Exception_Handlers => Excep_Handlers));
3060 Analyze (Handled_Statement_Sequence (N));
3062 end Expand_Thread_Body;
3064 -- Start of processing for Expand_N_Subprogram_Body
3067 -- Set L to either the list of declarations if present, or
3068 -- to the list of statements if no declarations are present.
3069 -- This is used to insert new stuff at the start.
3071 if Is_Non_Empty_List (Declarations (N)) then
3072 L := Declarations (N);
3074 L := Statements (Handled_Statement_Sequence (N));
3077 -- Need poll on entry to subprogram if polling enabled. We only
3078 -- do this for non-empty subprograms, since it does not seem
3079 -- necessary to poll for a dummy null subprogram.
3081 if Is_Non_Empty_List (L) then
3082 Generate_Poll_Call (First (L));
3085 -- Find entity for subprogram
3087 Body_Id := Defining_Entity (N);
3089 if Present (Corresponding_Spec (N)) then
3090 Spec_Id := Corresponding_Spec (N);
3095 -- If this is a Pure function which has any parameters whose root
3096 -- type is System.Address, reset the Pure indication, since it will
3097 -- likely cause incorrect code to be generated as the parameter is
3098 -- probably a pointer, and the fact that the same pointer is passed
3099 -- does not mean that the same value is being referenced.
3101 -- Note that if the programmer gave an explicit Pure_Function pragma,
3102 -- then we believe the programmer, and leave the subprogram Pure.
3104 -- This code should probably be at the freeze point, so that it
3105 -- happens even on a -gnatc (or more importantly -gnatt) compile
3106 -- so that the semantic tree has Is_Pure set properly ???
3108 if Is_Pure (Spec_Id)
3109 and then Is_Subprogram (Spec_Id)
3110 and then not Has_Pragma_Pure_Function (Spec_Id)
3113 F : Entity_Id := First_Formal (Spec_Id);
3116 while Present (F) loop
3117 if Is_RTE (Root_Type (Etype (F)), RE_Address) then
3118 Set_Is_Pure (Spec_Id, False);
3120 if Spec_Id /= Body_Id then
3121 Set_Is_Pure (Body_Id, False);
3132 -- Initialize any scalar OUT args if Initialize/Normalize_Scalars
3134 if Init_Or_Norm_Scalars and then Is_Subprogram (Spec_Id) then
3136 F : Entity_Id := First_Formal (Spec_Id);
3137 V : constant Boolean := Validity_Checks_On;
3140 -- We turn off validity checking, since we do not want any
3141 -- check on the initializing value itself (which we know
3142 -- may well be invalid!)
3144 Validity_Checks_On := False;
3146 -- Loop through formals
3148 while Present (F) loop
3149 if Is_Scalar_Type (Etype (F))
3150 and then Ekind (F) = E_Out_Parameter
3152 Insert_Before_And_Analyze (First (L),
3153 Make_Assignment_Statement (Loc,
3154 Name => New_Occurrence_Of (F, Loc),
3155 Expression => Get_Simple_Init_Val (Etype (F), Loc)));
3161 Validity_Checks_On := V;
3165 -- Clear out statement list for stubbed procedure
3167 if Present (Corresponding_Spec (N)) then
3168 Set_Elaboration_Flag (N, Spec_Id);
3170 if Convention (Spec_Id) = Convention_Stubbed
3171 or else Is_Eliminated (Spec_Id)
3173 Set_Declarations (N, Empty_List);
3174 Set_Handled_Statement_Sequence (N,
3175 Make_Handled_Sequence_Of_Statements (Loc,
3176 Statements => New_List (
3177 Make_Null_Statement (Loc))));
3182 Scop := Scope (Spec_Id);
3184 -- Returns_By_Ref flag is normally set when the subprogram is frozen
3185 -- but subprograms with no specs are not frozen
3188 Typ : constant Entity_Id := Etype (Spec_Id);
3189 Utyp : constant Entity_Id := Underlying_Type (Typ);
3192 if not Acts_As_Spec (N)
3193 and then Nkind (Parent (Parent (Spec_Id))) /=
3194 N_Subprogram_Body_Stub
3198 elsif Is_Return_By_Reference_Type (Typ) then
3199 Set_Returns_By_Ref (Spec_Id);
3201 elsif Present (Utyp) and then Controlled_Type (Utyp) then
3202 Set_Returns_By_Ref (Spec_Id);
3206 -- For a procedure, we add a return for all possible syntactic ends
3207 -- of the subprogram. Note that reanalysis is not necessary in this
3208 -- case since it would require a lot of work and accomplish nothing.
3210 if Ekind (Spec_Id) = E_Procedure
3211 or else Ekind (Spec_Id) = E_Generic_Procedure
3213 Add_Return (Statements (H));
3215 if Present (Exception_Handlers (H)) then
3216 Except_H := First_Non_Pragma (Exception_Handlers (H));
3218 while Present (Except_H) loop
3219 Add_Return (Statements (Except_H));
3220 Next_Non_Pragma (Except_H);
3224 -- For a function, we must deal with the case where there is at
3225 -- least one missing return. What we do is to wrap the entire body
3226 -- of the function in a block:
3239 -- raise Program_Error;
3242 -- This approach is necessary because the raise must be signalled
3243 -- to the caller, not handled by any local handler (RM 6.4(11)).
3245 -- Note: we do not need to analyze the constructed sequence here,
3246 -- since it has no handler, and an attempt to analyze the handled
3247 -- statement sequence twice is risky in various ways (e.g. the
3248 -- issue of expanding cleanup actions twice).
3250 elsif Has_Missing_Return (Spec_Id) then
3252 Hloc : constant Source_Ptr := Sloc (H);
3253 Blok : constant Node_Id :=
3254 Make_Block_Statement (Hloc,
3255 Handled_Statement_Sequence => H);
3256 Rais : constant Node_Id :=
3257 Make_Raise_Program_Error (Hloc,
3258 Reason => PE_Missing_Return);
3261 Set_Handled_Statement_Sequence (N,
3262 Make_Handled_Sequence_Of_Statements (Hloc,
3263 Statements => New_List (Blok, Rais)));
3265 New_Scope (Spec_Id);
3272 -- Add discriminal renamings to protected subprograms.
3273 -- Install new discriminals for expansion of the next
3274 -- subprogram of this protected type, if any.
3276 if Is_List_Member (N)
3277 and then Present (Parent (List_Containing (N)))
3278 and then Nkind (Parent (List_Containing (N))) = N_Protected_Body
3280 Add_Discriminal_Declarations
3281 (Declarations (N), Scop, Name_uObject, Loc);
3282 Add_Private_Declarations (Declarations (N), Scop, Name_uObject, Loc);
3284 -- Associate privals and discriminals with the next protected
3285 -- operation body to be expanded. These are used to expand
3286 -- references to private data objects and discriminants,
3289 Next_Op := Next_Protected_Operation (N);
3291 if Present (Next_Op) then
3292 Dec := Parent (Base_Type (Scop));
3293 Set_Privals (Dec, Next_Op, Loc);
3294 Set_Discriminals (Dec);
3298 -- If subprogram contains a parameterless recursive call, then we may
3299 -- have an infinite recursion, so see if we can generate code to check
3300 -- for this possibility if storage checks are not suppressed.
3302 if Ekind (Spec_Id) = E_Procedure
3303 and then Has_Recursive_Call (Spec_Id)
3304 and then not Storage_Checks_Suppressed (Spec_Id)
3306 Detect_Infinite_Recursion (N, Spec_Id);
3309 -- Finally, if we are in Normalize_Scalars mode, then any scalar out
3310 -- parameters must be initialized to the appropriate default value.
3312 if Ekind (Spec_Id) = E_Procedure and then Normalize_Scalars then
3319 Formal := First_Formal (Spec_Id);
3321 while Present (Formal) loop
3322 Floc := Sloc (Formal);
3324 if Ekind (Formal) = E_Out_Parameter
3325 and then Is_Scalar_Type (Etype (Formal))
3328 Make_Assignment_Statement (Floc,
3329 Name => New_Occurrence_Of (Formal, Floc),
3331 Get_Simple_Init_Val (Etype (Formal), Floc));
3332 Prepend (Stm, Declarations (N));
3336 Next_Formal (Formal);
3341 -- Deal with thread body
3343 if Is_Thread_Body (Spec_Id) then
3347 -- If the subprogram does not have pending instantiations, then we
3348 -- must generate the subprogram descriptor now, since the code for
3349 -- the subprogram is complete, and this is our last chance. However
3350 -- if there are pending instantiations, then the code is not
3351 -- complete, and we will delay the generation.
3353 if Is_Subprogram (Spec_Id)
3354 and then not Delay_Subprogram_Descriptors (Spec_Id)
3356 Generate_Subprogram_Descriptor_For_Subprogram (N, Spec_Id);
3359 -- Set to encode entity names in package body before gigi is called
3361 Qualify_Entity_Names (N);
3362 end Expand_N_Subprogram_Body;
3364 -----------------------------------
3365 -- Expand_N_Subprogram_Body_Stub --
3366 -----------------------------------
3368 procedure Expand_N_Subprogram_Body_Stub (N : Node_Id) is
3370 if Present (Corresponding_Body (N)) then
3371 Expand_N_Subprogram_Body (
3372 Unit_Declaration_Node (Corresponding_Body (N)));
3374 end Expand_N_Subprogram_Body_Stub;
3376 -------------------------------------
3377 -- Expand_N_Subprogram_Declaration --
3378 -------------------------------------
3380 -- If the declaration appears within a protected body, it is a private
3381 -- operation of the protected type. We must create the corresponding
3382 -- protected subprogram an associated formals. For a normal protected
3383 -- operation, this is done when expanding the protected type declaration.
3385 procedure Expand_N_Subprogram_Declaration (N : Node_Id) is
3386 Loc : constant Source_Ptr := Sloc (N);
3387 Subp : constant Entity_Id := Defining_Entity (N);
3388 Scop : constant Entity_Id := Scope (Subp);
3389 Prot_Decl : Node_Id;
3391 Prot_Id : Entity_Id;
3394 -- Deal with case of protected subprogram
3396 if Is_List_Member (N)
3397 and then Present (Parent (List_Containing (N)))
3398 and then Nkind (Parent (List_Containing (N))) = N_Protected_Body
3399 and then Is_Protected_Type (Scop)
3401 if No (Protected_Body_Subprogram (Subp)) then
3403 Make_Subprogram_Declaration (Loc,
3405 Build_Protected_Sub_Specification
3406 (N, Scop, Unprotected => True));
3408 -- The protected subprogram is declared outside of the protected
3409 -- body. Given that the body has frozen all entities so far, we
3410 -- analyze the subprogram and perform freezing actions explicitly.
3411 -- If the body is a subunit, the insertion point is before the
3412 -- stub in the parent.
3414 Prot_Bod := Parent (List_Containing (N));
3416 if Nkind (Parent (Prot_Bod)) = N_Subunit then
3417 Prot_Bod := Corresponding_Stub (Parent (Prot_Bod));
3420 Insert_Before (Prot_Bod, Prot_Decl);
3421 Prot_Id := Defining_Unit_Name (Specification (Prot_Decl));
3423 New_Scope (Scope (Scop));
3424 Analyze (Prot_Decl);
3425 Create_Extra_Formals (Prot_Id);
3426 Set_Protected_Body_Subprogram (Subp, Prot_Id);
3430 end Expand_N_Subprogram_Declaration;
3432 ---------------------------------------
3433 -- Expand_Protected_Object_Reference --
3434 ---------------------------------------
3436 function Expand_Protected_Object_Reference
3441 Loc : constant Source_Ptr := Sloc (N);
3448 Rec := Make_Identifier (Loc, Name_uObject);
3449 Set_Etype (Rec, Corresponding_Record_Type (Scop));
3451 -- Find enclosing protected operation, and retrieve its first
3452 -- parameter, which denotes the enclosing protected object.
3453 -- If the enclosing operation is an entry, we are immediately
3454 -- within the protected body, and we can retrieve the object
3455 -- from the service entries procedure. A barrier function has
3456 -- has the same signature as an entry. A barrier function is
3457 -- compiled within the protected object, but unlike protected
3458 -- operations its never needs locks, so that its protected body
3459 -- subprogram points to itself.
3461 Proc := Current_Scope;
3463 while Present (Proc)
3464 and then Scope (Proc) /= Scop
3466 Proc := Scope (Proc);
3469 Corr := Protected_Body_Subprogram (Proc);
3473 -- Previous error left expansion incomplete.
3474 -- Nothing to do on this call.
3481 (First (Parameter_Specifications (Parent (Corr))));
3483 if Is_Subprogram (Proc)
3484 and then Proc /= Corr
3486 -- Protected function or procedure.
3488 Set_Entity (Rec, Param);
3490 -- Rec is a reference to an entity which will not be in scope
3491 -- when the call is reanalyzed, and needs no further analysis.
3496 -- Entry or barrier function for entry body.
3497 -- The first parameter of the entry body procedure is a
3498 -- pointer to the object. We create a local variable
3499 -- of the proper type, duplicating what is done to define
3500 -- _object later on.
3504 Obj_Ptr : constant Entity_Id := Make_Defining_Identifier (Loc,
3506 New_Internal_Name ('T'));
3510 Make_Full_Type_Declaration (Loc,
3511 Defining_Identifier => Obj_Ptr,
3513 Make_Access_To_Object_Definition (Loc,
3514 Subtype_Indication =>
3516 (Corresponding_Record_Type (Scop), Loc))));
3518 Insert_Actions (N, Decls);
3519 Insert_Actions (N, Freeze_Entity (Obj_Ptr, Sloc (N)));
3522 Make_Explicit_Dereference (Loc,
3523 Unchecked_Convert_To (Obj_Ptr,
3524 New_Occurrence_Of (Param, Loc)));
3526 -- Analyze new actual. Other actuals in calls are already
3527 -- analyzed and the list of actuals is not renalyzed after
3530 Set_Parent (Rec, N);
3536 end Expand_Protected_Object_Reference;
3538 --------------------------------------
3539 -- Expand_Protected_Subprogram_Call --
3540 --------------------------------------
3542 procedure Expand_Protected_Subprogram_Call
3550 -- If the protected object is not an enclosing scope, this is
3551 -- an inter-object function call. Inter-object procedure
3552 -- calls are expanded by Exp_Ch9.Build_Simple_Entry_Call.
3553 -- The call is intra-object only if the subprogram being
3554 -- called is in the protected body being compiled, and if the
3555 -- protected object in the call is statically the enclosing type.
3556 -- The object may be an component of some other data structure,
3557 -- in which case this must be handled as an inter-object call.
3559 if not In_Open_Scopes (Scop)
3560 or else not Is_Entity_Name (Name (N))
3562 if Nkind (Name (N)) = N_Selected_Component then
3563 Rec := Prefix (Name (N));
3566 pragma Assert (Nkind (Name (N)) = N_Indexed_Component);
3567 Rec := Prefix (Prefix (Name (N)));
3570 Build_Protected_Subprogram_Call (N,
3571 Name => New_Occurrence_Of (Subp, Sloc (N)),
3572 Rec => Convert_Concurrent (Rec, Etype (Rec)),
3576 Rec := Expand_Protected_Object_Reference (N, Scop);
3582 Build_Protected_Subprogram_Call (N,
3591 -- If it is a function call it can appear in elaboration code and
3592 -- the called entity must be frozen here.
3594 if Ekind (Subp) = E_Function then
3595 Freeze_Expression (Name (N));
3597 end Expand_Protected_Subprogram_Call;
3599 -----------------------
3600 -- Freeze_Subprogram --
3601 -----------------------
3603 procedure Freeze_Subprogram (N : Node_Id) is
3604 E : constant Entity_Id := Entity (N);
3607 -- When a primitive is frozen, enter its name in the corresponding
3608 -- dispatch table. If the DTC_Entity field is not set this is an
3609 -- overridden primitive that can be ignored. We suppress the
3610 -- initialization of the dispatch table entry when Java_VM because
3611 -- the dispatching mechanism is handled internally by the JVM.
3613 if Is_Dispatching_Operation (E)
3614 and then not Is_Abstract (E)
3615 and then Present (DTC_Entity (E))
3616 and then not Is_CPP_Class (Scope (DTC_Entity (E)))
3617 and then not Java_VM
3619 Check_Overriding_Operation (E);
3620 Insert_After (N, Fill_DT_Entry (Sloc (N), E));
3623 -- Mark functions that return by reference. Note that it cannot be
3624 -- part of the normal semantic analysis of the spec since the
3625 -- underlying returned type may not be known yet (for private types)
3628 Typ : constant Entity_Id := Etype (E);
3629 Utyp : constant Entity_Id := Underlying_Type (Typ);
3632 if Is_Return_By_Reference_Type (Typ) then
3633 Set_Returns_By_Ref (E);
3635 elsif Present (Utyp) and then Controlled_Type (Utyp) then
3636 Set_Returns_By_Ref (E);
3639 end Freeze_Subprogram;