1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2010, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Casing; use Casing;
28 with Einfo; use Einfo;
29 with Errout; use Errout;
30 with Exp_Dist; use Exp_Dist;
31 with Exp_Tss; use Exp_Tss;
32 with Nlists; use Nlists;
33 with Nmake; use Nmake;
34 with Namet; use Namet;
36 with Rtsfind; use Rtsfind;
38 with Sem_Aux; use Sem_Aux;
39 with Sem_Disp; use Sem_Disp;
40 with Sem_Eval; use Sem_Eval;
41 with Sem_Res; use Sem_Res;
42 with Sem_Util; use Sem_Util;
43 with Sinfo; use Sinfo;
44 with Stand; use Stand;
45 with Stringt; use Stringt;
46 with Tbuild; use Tbuild;
47 with Uintp; use Uintp;
49 package body Sem_Dist is
51 -----------------------
52 -- Local Subprograms --
53 -----------------------
55 procedure RAS_E_Dereference (Pref : Node_Id);
56 -- Handles explicit dereference of Remote Access to Subprograms
58 function Full_Qualified_Name (E : Entity_Id) return String_Id;
59 -- returns the full qualified name of the entity in lower case
61 -------------------------
62 -- Add_Stub_Constructs --
63 -------------------------
65 procedure Add_Stub_Constructs (N : Node_Id) is
66 U : constant Node_Id := Unit (N);
67 Spec : Entity_Id := Empty;
70 -- Unit that will be expanded
73 pragma Assert (Distribution_Stub_Mode /= No_Stubs);
75 if Nkind (U) = N_Package_Declaration then
76 Spec := Defining_Entity (Specification (U));
78 elsif Nkind (U) = N_Package_Body then
79 Spec := Corresponding_Spec (U);
81 else pragma Assert (Nkind (U) = N_Package_Instantiation);
82 Exp := Instance_Spec (U);
83 Spec := Defining_Entity (Specification (Exp));
86 pragma Assert (Is_Shared_Passive (Spec)
87 or else Is_Remote_Call_Interface (Spec));
89 if Distribution_Stub_Mode = Generate_Caller_Stub_Body then
90 if Is_Shared_Passive (Spec) then
92 elsif Nkind (U) = N_Package_Body then
94 ("Specification file expected from command line", U);
96 Expand_Calling_Stubs_Bodies (Exp);
100 if Is_Shared_Passive (Spec) then
101 Build_Passive_Partition_Stub (Exp);
103 Expand_Receiving_Stubs_Bodies (Exp);
107 end Add_Stub_Constructs;
109 ---------------------------------------
110 -- Build_RAS_Primitive_Specification --
111 ---------------------------------------
113 function Build_RAS_Primitive_Specification
114 (Subp_Spec : Node_Id;
115 Remote_Object_Type : Node_Id) return Node_Id
117 Loc : constant Source_Ptr := Sloc (Subp_Spec);
119 Primitive_Spec : constant Node_Id :=
120 Copy_Specification (Loc,
122 New_Name => Name_uCall);
124 Subtype_Mark_For_Self : Node_Id;
127 if No (Parameter_Specifications (Primitive_Spec)) then
128 Set_Parameter_Specifications (Primitive_Spec, New_List);
131 if Nkind (Remote_Object_Type) in N_Entity then
132 Subtype_Mark_For_Self :=
133 New_Occurrence_Of (Remote_Object_Type, Loc);
135 Subtype_Mark_For_Self := Remote_Object_Type;
139 Parameter_Specifications (Primitive_Spec),
140 Make_Parameter_Specification (Loc,
141 Defining_Identifier =>
142 Make_Defining_Identifier (Loc, Name_uS),
144 Make_Access_Definition (Loc,
146 Subtype_Mark_For_Self)));
148 -- Trick later semantic analysis into considering this operation as a
149 -- primitive (dispatching) operation of tagged type Obj_Type.
151 Set_Comes_From_Source (
152 Defining_Unit_Name (Primitive_Spec), True);
154 return Primitive_Spec;
155 end Build_RAS_Primitive_Specification;
157 -------------------------
158 -- Full_Qualified_Name --
159 -------------------------
161 function Full_Qualified_Name (E : Entity_Id) return String_Id is
162 Ent : Entity_Id := E;
163 Parent_Name : String_Id := No_String;
166 -- Deals properly with child units
168 if Nkind (Ent) = N_Defining_Program_Unit_Name then
169 Ent := Defining_Identifier (Ent);
172 -- Compute recursively the qualification (only "Standard" has no scope)
174 if Present (Scope (Scope (Ent))) then
175 Parent_Name := Full_Qualified_Name (Scope (Ent));
178 -- Every entity should have a name except some expanded blocks. Do not
179 -- bother about those.
181 if Chars (Ent) = No_Name then
185 -- Add a period between Name and qualification
187 if Parent_Name /= No_String then
188 Start_String (Parent_Name);
189 Store_String_Char (Get_Char_Code ('.'));
194 -- Generates the entity name in upper case
196 Get_Name_String (Chars (Ent));
197 Set_Casing (All_Lower_Case);
198 Store_String_Chars (Name_Buffer (1 .. Name_Len));
200 end Full_Qualified_Name;
206 function Get_PCS_Name return PCS_Names is
209 Chars (Entity (Expression (Parent (RTE (RE_DSA_Implementation)))));
212 ---------------------
213 -- Get_PCS_Version --
214 ---------------------
216 function Get_PCS_Version return Int is
217 PCS_Version_Entity : Entity_Id;
221 if RTE_Available (RE_PCS_Version) then
222 PCS_Version_Entity := RTE (RE_PCS_Version);
223 pragma Assert (Ekind (PCS_Version_Entity) = E_Named_Integer);
225 UI_To_Int (Expr_Value (Constant_Value (PCS_Version_Entity)));
228 -- Case of System.Partition_Interface.PCS_Version not found:
229 -- return a null version.
237 ------------------------
238 -- Is_All_Remote_Call --
239 ------------------------
241 function Is_All_Remote_Call (N : Node_Id) return Boolean is
245 if Nkind_In (N, N_Function_Call, N_Procedure_Call_Statement)
246 and then Nkind (Name (N)) in N_Has_Entity
247 and then Is_Remote_Call_Interface (Entity (Name (N)))
248 and then Has_All_Calls_Remote (Scope (Entity (Name (N))))
249 and then Comes_From_Source (N)
251 Par := Parent (Entity (Name (N)));
253 and then (Nkind (Par) /= N_Package_Specification
254 or else Is_Wrapper_Package (Defining_Entity (Par)))
259 if Present (Par) then
261 not Scope_Within_Or_Same (Current_Scope, Defining_Entity (Par));
268 end Is_All_Remote_Call;
270 ---------------------------------
271 -- Is_RACW_Stub_Type_Operation --
272 ---------------------------------
274 function Is_RACW_Stub_Type_Operation (Op : Entity_Id) return Boolean is
275 Dispatching_Type : Entity_Id;
279 when E_Function | E_Procedure =>
280 Dispatching_Type := Find_Dispatching_Type (Op);
281 return Present (Dispatching_Type)
282 and then Is_RACW_Stub_Type (Dispatching_Type)
283 and then not Is_Internal (Op);
288 end Is_RACW_Stub_Type_Operation;
290 ------------------------------------
291 -- Package_Specification_Of_Scope --
292 ------------------------------------
294 function Package_Specification_Of_Scope (E : Entity_Id) return Node_Id is
299 while Nkind (N) /= N_Package_Specification loop
304 end Package_Specification_Of_Scope;
306 --------------------------
307 -- Process_Partition_ID --
308 --------------------------
310 procedure Process_Partition_Id (N : Node_Id) is
311 Loc : constant Source_Ptr := Sloc (N);
314 Get_Pt_Id_Call : Node_Id;
315 Prefix_String : String_Id;
316 Typ : constant Entity_Id := Etype (N);
319 -- In case prefix is not a library unit entity, get the entity
322 Ety := Entity (Prefix (N));
323 while (Present (Scope (Ety))
324 and then Scope (Ety) /= Standard_Standard)
325 and not Is_Child_Unit (Ety)
330 -- Retrieve the proper function to call
332 if Is_Remote_Call_Interface (Ety) then
333 Get_Pt_Id := New_Occurrence_Of
334 (RTE (RE_Get_Active_Partition_Id), Loc);
336 elsif Is_Shared_Passive (Ety) then
337 Get_Pt_Id := New_Occurrence_Of
338 (RTE (RE_Get_Passive_Partition_Id), Loc);
341 Get_Pt_Id := New_Occurrence_Of
342 (RTE (RE_Get_Local_Partition_Id), Loc);
345 -- Get and store the String_Id corresponding to the name of the
346 -- library unit whose Partition_Id is needed.
348 Get_Library_Unit_Name_String (Unit_Declaration_Node (Ety));
349 Prefix_String := String_From_Name_Buffer;
351 -- Build the function call which will replace the attribute
353 if Is_Remote_Call_Interface (Ety) or else Is_Shared_Passive (Ety) then
355 Make_Function_Call (Loc,
357 Parameter_Associations =>
358 New_List (Make_String_Literal (Loc, Prefix_String)));
361 Get_Pt_Id_Call := Make_Function_Call (Loc, Get_Pt_Id);
364 -- Replace the attribute node by a conversion of the function call
365 -- to the target type.
367 Rewrite (N, Convert_To (Typ, Get_Pt_Id_Call));
368 Analyze_And_Resolve (N, Typ);
369 end Process_Partition_Id;
371 ----------------------------------
372 -- Process_Remote_AST_Attribute --
373 ----------------------------------
375 procedure Process_Remote_AST_Attribute
377 New_Type : Entity_Id)
379 Loc : constant Source_Ptr := Sloc (N);
380 Remote_Subp : Entity_Id;
381 Tick_Access_Conv_Call : Node_Id;
382 Remote_Subp_Decl : Node_Id;
383 RS_Pkg_Specif : Node_Id;
384 RS_Pkg_E : Entity_Id;
385 RAS_Type : Entity_Id := New_Type;
387 All_Calls_Remote_E : Entity_Id;
388 Attribute_Subp : Entity_Id;
391 -- Check if we have to expand the access attribute
393 Remote_Subp := Entity (Prefix (N));
395 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
399 if Ekind (RAS_Type) /= E_Record_Type then
400 RAS_Type := Equivalent_Type (RAS_Type);
403 Attribute_Subp := TSS (RAS_Type, TSS_RAS_Access);
404 pragma Assert (Present (Attribute_Subp));
405 Remote_Subp_Decl := Unit_Declaration_Node (Remote_Subp);
407 if Nkind (Remote_Subp_Decl) = N_Subprogram_Body then
408 Remote_Subp := Corresponding_Spec (Remote_Subp_Decl);
409 Remote_Subp_Decl := Unit_Declaration_Node (Remote_Subp);
412 RS_Pkg_Specif := Parent (Remote_Subp_Decl);
413 RS_Pkg_E := Defining_Entity (RS_Pkg_Specif);
416 Boolean_Literals (Ekind (Remote_Subp) = E_Procedure
417 and then Is_Asynchronous (Remote_Subp));
419 All_Calls_Remote_E :=
420 Boolean_Literals (Has_All_Calls_Remote (RS_Pkg_E));
422 Tick_Access_Conv_Call :=
423 Make_Function_Call (Loc,
424 Name => New_Occurrence_Of (Attribute_Subp, Loc),
425 Parameter_Associations =>
427 Make_String_Literal (Loc,
428 Strval => Full_Qualified_Name (RS_Pkg_E)),
429 Build_Subprogram_Id (Loc, Remote_Subp),
430 New_Occurrence_Of (Async_E, Loc),
431 New_Occurrence_Of (All_Calls_Remote_E, Loc)));
433 Rewrite (N, Tick_Access_Conv_Call);
434 Analyze_And_Resolve (N, RAS_Type);
435 end Process_Remote_AST_Attribute;
437 ------------------------------------
438 -- Process_Remote_AST_Declaration --
439 ------------------------------------
441 procedure Process_Remote_AST_Declaration (N : Node_Id) is
442 Loc : constant Source_Ptr := Sloc (N);
443 User_Type : constant Node_Id := Defining_Identifier (N);
444 Scop : constant Entity_Id := Scope (User_Type);
445 Is_RCI : constant Boolean := Is_Remote_Call_Interface (Scop);
446 Is_RT : constant Boolean := Is_Remote_Types (Scop);
447 Type_Def : constant Node_Id := Type_Definition (N);
450 Is_Degenerate : Boolean;
451 -- True iff this RAS has an access formal parameter (see
452 -- Exp_Dist.Add_RAS_Dereference_TSS for details).
454 Subpkg : constant Entity_Id := Make_Temporary (Loc, 'S');
455 Subpkg_Decl : Node_Id;
456 Subpkg_Body : Node_Id;
457 Vis_Decls : constant List_Id := New_List;
458 Priv_Decls : constant List_Id := New_List;
460 Obj_Type : constant Entity_Id :=
461 Make_Defining_Identifier (Loc,
462 New_External_Name (Chars (User_Type), 'R'));
464 Full_Obj_Type : constant Entity_Id :=
465 Make_Defining_Identifier (Loc, Chars (Obj_Type));
467 RACW_Type : constant Entity_Id :=
468 Make_Defining_Identifier (Loc,
469 New_External_Name (Chars (User_Type), 'P'));
471 Fat_Type : constant Entity_Id :=
472 Make_Defining_Identifier (Loc, Chars (User_Type));
474 Fat_Type_Decl : Node_Id;
477 Is_Degenerate := False;
478 Parameter := First (Parameter_Specifications (Type_Def));
479 while Present (Parameter) loop
480 if Nkind (Parameter_Type (Parameter)) = N_Access_Definition then
481 Error_Msg_N ("formal parameter& has anonymous access type?",
482 Defining_Identifier (Parameter));
483 Is_Degenerate := True;
490 if Is_Degenerate then
492 ("remote access-to-subprogram type& can only be null?",
493 Defining_Identifier (Parameter), User_Type);
495 -- The only legal value for a RAS with a formal parameter of an
496 -- anonymous access type is null, because it cannot be subtype-
497 -- conformant with any legal remote subprogram declaration. In this
498 -- case, we cannot generate a corresponding primitive operation.
502 if Get_PCS_Name = Name_No_DSA then
506 -- The tagged private type, primitive operation and RACW type associated
507 -- with a RAS need to all be declared in a subpackage of the one that
508 -- contains the RAS declaration, because the primitive of the object
509 -- type, and the associated primitive of the stub type, need to be
510 -- dispatching operations of these types, and the profile of the RAS
511 -- might contain tagged types declared in the same scope.
513 Append_To (Vis_Decls,
514 Make_Private_Type_Declaration (Loc,
515 Defining_Identifier => Obj_Type,
516 Abstract_Present => True,
517 Tagged_Present => True,
518 Limited_Present => True));
520 Append_To (Priv_Decls,
521 Make_Full_Type_Declaration (Loc,
522 Defining_Identifier => Full_Obj_Type,
524 Make_Record_Definition (Loc,
525 Abstract_Present => True,
526 Tagged_Present => True,
527 Limited_Present => True,
528 Null_Present => True,
529 Component_List => Empty)));
531 -- Trick semantic analysis into swapping the public and full view when
532 -- freezing the public view.
534 Set_Comes_From_Source (Full_Obj_Type, True);
536 if not Is_Degenerate then
537 Append_To (Vis_Decls,
538 Make_Abstract_Subprogram_Declaration (Loc,
539 Specification => Build_RAS_Primitive_Specification (
540 Subp_Spec => Type_Def,
541 Remote_Object_Type => Obj_Type)));
544 Append_To (Vis_Decls,
545 Make_Full_Type_Declaration (Loc,
546 Defining_Identifier => RACW_Type,
548 Make_Access_To_Object_Definition (Loc,
550 Subtype_Indication =>
551 Make_Attribute_Reference (Loc,
552 Prefix => New_Occurrence_Of (Obj_Type, Loc),
553 Attribute_Name => Name_Class))));
555 Set_Is_Remote_Call_Interface (RACW_Type, Is_RCI);
556 Set_Is_Remote_Types (RACW_Type, Is_RT);
559 Make_Package_Declaration (Loc,
560 Make_Package_Specification (Loc,
561 Defining_Unit_Name => Subpkg,
562 Visible_Declarations => Vis_Decls,
563 Private_Declarations => Priv_Decls,
564 End_Label => New_Occurrence_Of (Subpkg, Loc)));
566 Set_Is_Remote_Call_Interface (Subpkg, Is_RCI);
567 Set_Is_Remote_Types (Subpkg, Is_RT);
568 Insert_After_And_Analyze (N, Subpkg_Decl);
570 -- Generate package body to receive RACW calling stubs
572 -- Note: Analyze_Declarations has an absolute requirement that the
573 -- declaration list be non-empty, so provide dummy null statement here.
576 Make_Package_Body (Loc,
577 Defining_Unit_Name => Make_Defining_Identifier (Loc, Chars (Subpkg)),
578 Declarations => New_List (Make_Null_Statement (Loc)));
579 Insert_After_And_Analyze (Subpkg_Decl, Subpkg_Body);
581 -- Many parts of the analyzer and expander expect
582 -- that the fat pointer type used to implement remote
583 -- access to subprogram types be a record.
584 -- Note: The structure of this type must be kept consistent
585 -- with the code generated by Remote_AST_Null_Value for the
586 -- corresponding 'null' expression.
588 Fat_Type_Decl := Make_Full_Type_Declaration (Loc,
589 Defining_Identifier => Fat_Type,
591 Make_Record_Definition (Loc,
593 Make_Component_List (Loc,
594 Component_Items => New_List (
595 Make_Component_Declaration (Loc,
596 Defining_Identifier =>
597 Make_Defining_Identifier (Loc, Name_Ras),
598 Component_Definition =>
599 Make_Component_Definition (Loc,
600 Aliased_Present => False,
601 Subtype_Indication =>
602 New_Occurrence_Of (RACW_Type, Loc)))))));
604 Set_Equivalent_Type (User_Type, Fat_Type);
605 Set_Corresponding_Remote_Type (Fat_Type, User_Type);
606 Insert_After_And_Analyze (Subpkg_Body, Fat_Type_Decl);
608 -- The reason we suppress the initialization procedure is that we know
609 -- that no initialization is required (even if Initialize_Scalars mode
610 -- is active), and there are order of elaboration problems if we do try
611 -- to generate an init proc for this created record type.
613 Set_Suppress_Init_Proc (Fat_Type);
615 if Expander_Active then
616 Add_RAST_Features (Parent (User_Type));
618 end Process_Remote_AST_Declaration;
620 -----------------------
621 -- RAS_E_Dereference --
622 -----------------------
624 procedure RAS_E_Dereference (Pref : Node_Id) is
625 Loc : constant Source_Ptr := Sloc (Pref);
627 New_Type : constant Entity_Id := Etype (Pref);
628 Explicit_Deref : constant Node_Id := Parent (Pref);
629 Deref_Subp_Call : constant Node_Id := Parent (Explicit_Deref);
630 Deref_Proc : Entity_Id;
634 if Nkind (Deref_Subp_Call) = N_Procedure_Call_Statement then
635 Params := Parameter_Associations (Deref_Subp_Call);
637 if Present (Params) then
638 Prepend (Pref, Params);
640 Params := New_List (Pref);
643 elsif Nkind (Deref_Subp_Call) = N_Indexed_Component then
644 Params := Expressions (Deref_Subp_Call);
646 if Present (Params) then
647 Prepend (Pref, Params);
649 Params := New_List (Pref);
653 -- Context is not a call
658 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
662 Deref_Proc := TSS (New_Type, TSS_RAS_Dereference);
663 pragma Assert (Present (Deref_Proc));
665 if Ekind (Deref_Proc) = E_Function then
667 Make_Function_Call (Loc,
668 Name => New_Occurrence_Of (Deref_Proc, Loc),
669 Parameter_Associations => Params);
672 Make_Procedure_Call_Statement (Loc,
673 Name => New_Occurrence_Of (Deref_Proc, Loc),
674 Parameter_Associations => Params);
677 Rewrite (Deref_Subp_Call, Call_Node);
678 Analyze (Deref_Subp_Call);
679 end RAS_E_Dereference;
681 ------------------------------
682 -- Remote_AST_E_Dereference --
683 ------------------------------
685 function Remote_AST_E_Dereference (P : Node_Id) return Boolean is
686 ET : constant Entity_Id := Etype (P);
689 -- Perform the changes only on original dereferences, and only if
690 -- we are generating code.
692 if Comes_From_Source (P)
693 and then Is_Record_Type (ET)
694 and then (Is_Remote_Call_Interface (ET)
695 or else Is_Remote_Types (ET))
696 and then Present (Corresponding_Remote_Type (ET))
697 and then Nkind_In (Parent (Parent (P)), N_Procedure_Call_Statement,
699 and then Expander_Active
701 RAS_E_Dereference (P);
706 end Remote_AST_E_Dereference;
708 ------------------------------
709 -- Remote_AST_I_Dereference --
710 ------------------------------
712 function Remote_AST_I_Dereference (P : Node_Id) return Boolean is
713 ET : constant Entity_Id := Etype (P);
717 if Comes_From_Source (P)
718 and then (Is_Remote_Call_Interface (ET)
719 or else Is_Remote_Types (ET))
720 and then Present (Corresponding_Remote_Type (ET))
721 and then Ekind (Entity (P)) /= E_Function
724 Make_Explicit_Dereference (Sloc (P),
725 Prefix => Relocate_Node (P));
728 RAS_E_Dereference (Prefix (P));
733 end Remote_AST_I_Dereference;
735 ---------------------------
736 -- Remote_AST_Null_Value --
737 ---------------------------
739 function Remote_AST_Null_Value
741 Typ : Entity_Id) return Boolean
743 Loc : constant Source_Ptr := Sloc (N);
744 Target_Type : Entity_Id;
747 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
750 elsif Ekind (Typ) = E_Access_Subprogram_Type
751 and then (Is_Remote_Call_Interface (Typ)
752 or else Is_Remote_Types (Typ))
753 and then Comes_From_Source (N)
754 and then Expander_Active
756 -- Any null that comes from source and is of the RAS type must
757 -- be expanded, except if expansion is not active (nothing
758 -- gets expanded into the equivalent record type).
760 Target_Type := Equivalent_Type (Typ);
762 elsif Ekind (Typ) = E_Record_Type
763 and then Present (Corresponding_Remote_Type (Typ))
765 -- This is a record type representing a RAS type, this must be
771 -- We do not have to handle this case
778 Component_Associations => New_List (
779 Make_Component_Association (Loc,
780 Choices => New_List (Make_Identifier (Loc, Name_Ras)),
781 Expression => Make_Null (Loc)))));
782 Analyze_And_Resolve (N, Target_Type);
784 end Remote_AST_Null_Value;