1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2007, Free Software Foundation, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, USA. --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Casing; use Casing;
29 with Einfo; use Einfo;
30 with Errout; use Errout;
31 with Exp_Dist; use Exp_Dist;
32 with Exp_Tss; use Exp_Tss;
33 with Nlists; use Nlists;
34 with Nmake; use Nmake;
35 with Namet; use Namet;
37 with Rtsfind; use Rtsfind;
39 with Sem_Eval; use Sem_Eval;
40 with Sem_Res; use Sem_Res;
41 with Sem_Util; use Sem_Util;
42 with Sinfo; use Sinfo;
43 with Stand; use Stand;
44 with Stringt; use Stringt;
45 with Tbuild; use Tbuild;
46 with Uintp; use Uintp;
48 package body Sem_Dist is
50 -----------------------
51 -- Local Subprograms --
52 -----------------------
54 procedure RAS_E_Dereference (Pref : Node_Id);
55 -- Handles explicit dereference of Remote Access to Subprograms
57 function Full_Qualified_Name (E : Entity_Id) return String_Id;
58 -- returns the full qualified name of the entity in lower case
60 -------------------------
61 -- Add_Stub_Constructs --
62 -------------------------
64 procedure Add_Stub_Constructs (N : Node_Id) is
65 U : constant Node_Id := Unit (N);
66 Spec : Entity_Id := Empty;
67 Exp : Node_Id := U; -- Unit that will be expanded
70 pragma Assert (Distribution_Stub_Mode /= No_Stubs);
72 if Nkind (U) = N_Package_Declaration then
73 Spec := Defining_Entity (Specification (U));
75 elsif Nkind (U) = N_Package_Body then
76 Spec := Corresponding_Spec (U);
78 else pragma Assert (Nkind (U) = N_Package_Instantiation);
79 Exp := Instance_Spec (U);
80 Spec := Defining_Entity (Specification (Exp));
83 pragma Assert (Is_Shared_Passive (Spec)
84 or else Is_Remote_Call_Interface (Spec));
86 if Distribution_Stub_Mode = Generate_Caller_Stub_Body then
88 if Is_Shared_Passive (Spec) then
90 elsif Nkind (U) = N_Package_Body then
92 ("Specification file expected from command line", U);
94 Expand_Calling_Stubs_Bodies (Exp);
99 if Is_Shared_Passive (Spec) then
100 Build_Passive_Partition_Stub (Exp);
102 Expand_Receiving_Stubs_Bodies (Exp);
106 end Add_Stub_Constructs;
108 ---------------------------------------
109 -- Build_RAS_Primitive_Specification --
110 ---------------------------------------
112 function Build_RAS_Primitive_Specification
113 (Subp_Spec : Node_Id;
114 Remote_Object_Type : Node_Id) return Node_Id
116 Loc : constant Source_Ptr := Sloc (Subp_Spec);
118 Primitive_Spec : constant Node_Id :=
119 Copy_Specification (Loc,
121 New_Name => Name_uCall);
123 Subtype_Mark_For_Self : Node_Id;
126 if No (Parameter_Specifications (Primitive_Spec)) then
127 Set_Parameter_Specifications (Primitive_Spec, New_List);
130 if Nkind (Remote_Object_Type) in N_Entity then
131 Subtype_Mark_For_Self :=
132 New_Occurrence_Of (Remote_Object_Type, Loc);
134 Subtype_Mark_For_Self := Remote_Object_Type;
138 Parameter_Specifications (Primitive_Spec),
139 Make_Parameter_Specification (Loc,
140 Defining_Identifier =>
141 Make_Defining_Identifier (Loc, Name_uS),
143 Make_Access_Definition (Loc,
145 Subtype_Mark_For_Self)));
147 -- Trick later semantic analysis into considering this operation as a
148 -- primitive (dispatching) operation of tagged type Obj_Type.
150 Set_Comes_From_Source (
151 Defining_Unit_Name (Primitive_Spec), True);
153 return Primitive_Spec;
154 end Build_RAS_Primitive_Specification;
156 -------------------------
157 -- Full_Qualified_Name --
158 -------------------------
160 function Full_Qualified_Name (E : Entity_Id) return String_Id is
161 Ent : Entity_Id := E;
162 Parent_Name : String_Id := No_String;
165 -- Deals properly with child units
167 if Nkind (Ent) = N_Defining_Program_Unit_Name then
168 Ent := Defining_Identifier (Ent);
171 -- Compute recursively the qualification (only "Standard" has no scope)
173 if Present (Scope (Scope (Ent))) then
174 Parent_Name := Full_Qualified_Name (Scope (Ent));
177 -- Every entity should have a name except some expanded blocks. Do not
178 -- bother about those.
180 if Chars (Ent) = No_Name then
184 -- Add a period between Name and qualification
186 if Parent_Name /= No_String then
187 Start_String (Parent_Name);
188 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 (N) = N_Function_Call
246 or else Nkind (N) = N_Procedure_Call_Statement)
247 and then Nkind (Name (N)) in N_Has_Entity
248 and then Is_Remote_Call_Interface (Entity (Name (N)))
249 and then Has_All_Calls_Remote (Scope (Entity (Name (N))))
250 and then Comes_From_Source (N)
252 Par := Parent (Entity (Name (N)));
255 and then (Nkind (Par) /= N_Package_Specification
256 or else Is_Wrapper_Package (Defining_Entity (Par)))
261 if Present (Par) then
263 not Scope_Within_Or_Same (Current_Scope, Defining_Entity (Par));
270 end Is_All_Remote_Call;
272 ------------------------------------
273 -- Package_Specification_Of_Scope --
274 ------------------------------------
276 function Package_Specification_Of_Scope (E : Entity_Id) return Node_Id is
277 N : Node_Id := Parent (E);
279 while Nkind (N) /= N_Package_Specification loop
284 end Package_Specification_Of_Scope;
286 --------------------------
287 -- Process_Partition_ID --
288 --------------------------
290 procedure Process_Partition_Id (N : Node_Id) is
291 Loc : constant Source_Ptr := Sloc (N);
294 Get_Pt_Id_Call : Node_Id;
295 Prefix_String : String_Id;
296 Typ : constant Entity_Id := Etype (N);
299 Ety := Entity (Prefix (N));
301 -- In case prefix is not a library unit entity, get the entity
304 while (Present (Scope (Ety))
305 and then Scope (Ety) /= Standard_Standard)
306 and not Is_Child_Unit (Ety)
311 -- Retrieve the proper function to call
313 if Is_Remote_Call_Interface (Ety) then
314 Get_Pt_Id := New_Occurrence_Of
315 (RTE (RE_Get_Active_Partition_Id), Loc);
317 elsif Is_Shared_Passive (Ety) then
318 Get_Pt_Id := New_Occurrence_Of
319 (RTE (RE_Get_Passive_Partition_Id), Loc);
322 Get_Pt_Id := New_Occurrence_Of
323 (RTE (RE_Get_Local_Partition_Id), Loc);
326 -- Get and store the String_Id corresponding to the name of the
327 -- library unit whose Partition_Id is needed.
329 Get_Library_Unit_Name_String (Unit_Declaration_Node (Ety));
330 Prefix_String := String_From_Name_Buffer;
332 -- Build the function call which will replace the attribute
334 if Is_Remote_Call_Interface (Ety)
335 or else Is_Shared_Passive (Ety)
338 Make_Function_Call (Loc,
340 Parameter_Associations =>
341 New_List (Make_String_Literal (Loc, Prefix_String)));
344 Get_Pt_Id_Call := Make_Function_Call (Loc, Get_Pt_Id);
348 -- Replace the attribute node by a conversion of the function call
349 -- to the target type.
351 Rewrite (N, Convert_To (Typ, Get_Pt_Id_Call));
352 Analyze_And_Resolve (N, Typ);
353 end Process_Partition_Id;
355 ----------------------------------
356 -- Process_Remote_AST_Attribute --
357 ----------------------------------
359 procedure Process_Remote_AST_Attribute
361 New_Type : Entity_Id)
363 Loc : constant Source_Ptr := Sloc (N);
364 Remote_Subp : Entity_Id;
365 Tick_Access_Conv_Call : Node_Id;
366 Remote_Subp_Decl : Node_Id;
367 RS_Pkg_Specif : Node_Id;
368 RS_Pkg_E : Entity_Id;
369 RAS_Type : Entity_Id := New_Type;
371 All_Calls_Remote_E : Entity_Id;
372 Attribute_Subp : Entity_Id;
375 -- Check if we have to expand the access attribute
377 Remote_Subp := Entity (Prefix (N));
379 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
383 if Ekind (RAS_Type) /= E_Record_Type then
384 RAS_Type := Equivalent_Type (RAS_Type);
387 Attribute_Subp := TSS (RAS_Type, TSS_RAS_Access);
388 pragma Assert (Present (Attribute_Subp));
389 Remote_Subp_Decl := Unit_Declaration_Node (Remote_Subp);
391 if Nkind (Remote_Subp_Decl) = N_Subprogram_Body then
392 Remote_Subp := Corresponding_Spec (Remote_Subp_Decl);
393 Remote_Subp_Decl := Unit_Declaration_Node (Remote_Subp);
396 RS_Pkg_Specif := Parent (Remote_Subp_Decl);
397 RS_Pkg_E := Defining_Entity (RS_Pkg_Specif);
400 Boolean_Literals (Ekind (Remote_Subp) = E_Procedure
401 and then Is_Asynchronous (Remote_Subp));
403 All_Calls_Remote_E :=
404 Boolean_Literals (Has_All_Calls_Remote (RS_Pkg_E));
406 Tick_Access_Conv_Call :=
407 Make_Function_Call (Loc,
408 Name => New_Occurrence_Of (Attribute_Subp, Loc),
409 Parameter_Associations =>
411 Make_String_Literal (Loc, Full_Qualified_Name (RS_Pkg_E)),
412 Build_Subprogram_Id (Loc, Remote_Subp),
413 New_Occurrence_Of (Async_E, Loc),
414 New_Occurrence_Of (All_Calls_Remote_E, Loc)));
416 Rewrite (N, Tick_Access_Conv_Call);
417 Analyze_And_Resolve (N, RAS_Type);
418 end Process_Remote_AST_Attribute;
420 ------------------------------------
421 -- Process_Remote_AST_Declaration --
422 ------------------------------------
424 procedure Process_Remote_AST_Declaration (N : Node_Id) is
425 Loc : constant Source_Ptr := Sloc (N);
426 User_Type : constant Node_Id := Defining_Identifier (N);
427 Scop : constant Entity_Id := Scope (User_Type);
428 Is_RCI : constant Boolean := Is_Remote_Call_Interface (Scop);
429 Is_RT : constant Boolean := Is_Remote_Types (Scop);
430 Type_Def : constant Node_Id := Type_Definition (N);
433 Is_Degenerate : Boolean;
434 -- True iff this RAS has an access formal parameter (see
435 -- Exp_Dist.Add_RAS_Dereference_TSS for details).
437 Subpkg : constant Entity_Id :=
438 Make_Defining_Identifier (Loc,
439 New_Internal_Name ('S'));
440 Subpkg_Decl : Node_Id;
441 Subpkg_Body : Node_Id;
442 Vis_Decls : constant List_Id := New_List;
443 Priv_Decls : constant List_Id := New_List;
445 Obj_Type : constant Entity_Id :=
446 Make_Defining_Identifier (Loc,
447 New_External_Name (Chars (User_Type), 'R'));
449 Full_Obj_Type : constant Entity_Id :=
450 Make_Defining_Identifier (Loc,
453 RACW_Type : constant Entity_Id :=
454 Make_Defining_Identifier (Loc,
455 New_External_Name (Chars (User_Type), 'P'));
457 Fat_Type : constant Entity_Id :=
458 Make_Defining_Identifier (Loc,
461 Fat_Type_Decl : Node_Id;
464 Is_Degenerate := False;
465 Parameter := First (Parameter_Specifications (Type_Def));
466 while Present (Parameter) loop
467 if Nkind (Parameter_Type (Parameter)) = N_Access_Definition then
468 Error_Msg_N ("formal parameter& has anonymous access type?",
469 Defining_Identifier (Parameter));
470 Is_Degenerate := True;
477 if Is_Degenerate then
479 ("remote access-to-subprogram type& can only be null?",
480 Defining_Identifier (Parameter), User_Type);
482 -- The only legal value for a RAS with a formal parameter of an
483 -- anonymous access type is null, because it cannot be subtype-
484 -- conformant with any legal remote subprogram declaration. In this
485 -- case, we cannot generate a corresponding primitive operation.
489 if Get_PCS_Name = Name_No_DSA then
493 -- The tagged private type, primitive operation and RACW type associated
494 -- with a RAS need to all be declared in a subpackage of the one that
495 -- contains the RAS declaration, because the primitive of the object
496 -- type, and the associated primitive of the stub type, need to be
497 -- dispatching operations of these types, and the profile of the RAS
498 -- might contain tagged types declared in the same scope.
500 Append_To (Vis_Decls,
501 Make_Private_Type_Declaration (Loc,
502 Defining_Identifier => Obj_Type,
503 Abstract_Present => True,
504 Tagged_Present => True,
505 Limited_Present => True));
507 Append_To (Priv_Decls,
508 Make_Full_Type_Declaration (Loc,
509 Defining_Identifier =>
512 Make_Record_Definition (Loc,
513 Abstract_Present => True,
514 Tagged_Present => True,
515 Limited_Present => True,
516 Null_Present => True,
517 Component_List => Empty)));
519 -- Trick semantic analysis into swapping the public and full view when
520 -- freezing the public view.
522 Set_Comes_From_Source (Full_Obj_Type, True);
524 if not Is_Degenerate then
525 Append_To (Vis_Decls,
526 Make_Abstract_Subprogram_Declaration (Loc,
527 Specification => Build_RAS_Primitive_Specification (
528 Subp_Spec => Type_Def,
529 Remote_Object_Type => Obj_Type)));
532 Append_To (Vis_Decls,
533 Make_Full_Type_Declaration (Loc,
534 Defining_Identifier => RACW_Type,
536 Make_Access_To_Object_Definition (Loc,
538 Subtype_Indication =>
539 Make_Attribute_Reference (Loc,
541 New_Occurrence_Of (Obj_Type, Loc),
544 Set_Is_Remote_Call_Interface (RACW_Type, Is_RCI);
545 Set_Is_Remote_Types (RACW_Type, Is_RT);
548 Make_Package_Declaration (Loc,
549 Make_Package_Specification (Loc,
550 Defining_Unit_Name =>
552 Visible_Declarations =>
554 Private_Declarations =>
557 New_Occurrence_Of (Subpkg, Loc)));
558 Set_Is_Remote_Call_Interface (Subpkg, Is_RCI);
559 Set_Is_Remote_Types (Subpkg, Is_RT);
560 Insert_After_And_Analyze (N, Subpkg_Decl);
562 -- Generate package body to receive RACW calling stubs
563 -- Note: Analyze_Declarations has an absolute requirement that
564 -- the declaration list be non-empty, so we provide a dummy null
568 Make_Package_Body (Loc,
569 Defining_Unit_Name =>
570 Make_Defining_Identifier (Loc, Chars (Subpkg)),
571 Declarations => New_List (
572 Make_Null_Statement (Loc)));
573 Insert_After_And_Analyze (Subpkg_Decl, Subpkg_Body);
575 -- Many parts of the analyzer and expander expect
576 -- that the fat pointer type used to implement remote
577 -- access to subprogram types be a record.
578 -- Note: The structure of this type must be kept consistent
579 -- with the code generated by Remote_AST_Null_Value for the
580 -- corresponding 'null' expression.
582 Fat_Type_Decl := Make_Full_Type_Declaration (Loc,
583 Defining_Identifier => Fat_Type,
585 Make_Record_Definition (Loc,
587 Make_Component_List (Loc,
588 Component_Items => New_List (
589 Make_Component_Declaration (Loc,
590 Defining_Identifier =>
591 Make_Defining_Identifier (Loc, Name_Ras),
592 Component_Definition =>
593 Make_Component_Definition (Loc,
596 Subtype_Indication =>
597 New_Occurrence_Of (RACW_Type, Loc)))))));
598 Set_Equivalent_Type (User_Type, Fat_Type);
599 Set_Corresponding_Remote_Type (Fat_Type, User_Type);
600 Insert_After_And_Analyze (Subpkg_Body, Fat_Type_Decl);
602 -- The reason we suppress the initialization procedure is that we know
603 -- that no initialization is required (even if Initialize_Scalars mode
604 -- is active), and there are order of elaboration problems if we do try
605 -- to generate an init proc for this created record type.
607 Set_Suppress_Init_Proc (Fat_Type);
609 if Expander_Active then
610 Add_RAST_Features (Parent (User_Type));
612 end Process_Remote_AST_Declaration;
614 -----------------------
615 -- RAS_E_Dereference --
616 -----------------------
618 procedure RAS_E_Dereference (Pref : Node_Id) is
619 Loc : constant Source_Ptr := Sloc (Pref);
621 New_Type : constant Entity_Id := Etype (Pref);
622 Explicit_Deref : constant Node_Id := Parent (Pref);
623 Deref_Subp_Call : constant Node_Id := Parent (Explicit_Deref);
624 Deref_Proc : Entity_Id;
628 if Nkind (Deref_Subp_Call) = N_Procedure_Call_Statement then
629 Params := Parameter_Associations (Deref_Subp_Call);
631 if Present (Params) then
632 Prepend (Pref, Params);
634 Params := New_List (Pref);
637 elsif Nkind (Deref_Subp_Call) = N_Indexed_Component then
639 Params := Expressions (Deref_Subp_Call);
641 if Present (Params) then
642 Prepend (Pref, Params);
644 Params := New_List (Pref);
648 -- Context is not a call
653 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
657 Deref_Proc := TSS (New_Type, TSS_RAS_Dereference);
658 pragma Assert (Present (Deref_Proc));
660 if Ekind (Deref_Proc) = E_Function then
662 Make_Function_Call (Loc,
663 Name => New_Occurrence_Of (Deref_Proc, Loc),
664 Parameter_Associations => Params);
668 Make_Procedure_Call_Statement (Loc,
669 Name => New_Occurrence_Of (Deref_Proc, Loc),
670 Parameter_Associations => Params);
673 Rewrite (Deref_Subp_Call, Call_Node);
674 Analyze (Deref_Subp_Call);
675 end RAS_E_Dereference;
677 ------------------------------
678 -- Remote_AST_E_Dereference --
679 ------------------------------
681 function Remote_AST_E_Dereference (P : Node_Id) return Boolean is
682 ET : constant Entity_Id := Etype (P);
685 -- Perform the changes only on original dereferences, and only if
686 -- we are generating code.
688 if Comes_From_Source (P)
689 and then Is_Record_Type (ET)
690 and then (Is_Remote_Call_Interface (ET)
691 or else Is_Remote_Types (ET))
692 and then Present (Corresponding_Remote_Type (ET))
693 and then (Nkind (Parent (Parent (P))) = N_Procedure_Call_Statement
694 or else Nkind (Parent (Parent (P))) = N_Indexed_Component)
695 and then Expander_Active
697 RAS_E_Dereference (P);
702 end Remote_AST_E_Dereference;
704 ------------------------------
705 -- Remote_AST_I_Dereference --
706 ------------------------------
708 function Remote_AST_I_Dereference (P : Node_Id) return Boolean is
709 ET : constant Entity_Id := Etype (P);
713 if Comes_From_Source (P)
714 and then (Is_Remote_Call_Interface (ET)
715 or else Is_Remote_Types (ET))
716 and then Present (Corresponding_Remote_Type (ET))
717 and then Ekind (Entity (P)) /= E_Function
720 Make_Explicit_Dereference (Sloc (P),
721 Prefix => Relocate_Node (P));
724 RAS_E_Dereference (Prefix (P));
729 end Remote_AST_I_Dereference;
731 ---------------------------
732 -- Remote_AST_Null_Value --
733 ---------------------------
735 function Remote_AST_Null_Value
737 Typ : Entity_Id) return Boolean
739 Loc : constant Source_Ptr := Sloc (N);
740 Target_Type : Entity_Id;
743 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
746 elsif Ekind (Typ) = E_Access_Subprogram_Type
747 and then (Is_Remote_Call_Interface (Typ)
748 or else Is_Remote_Types (Typ))
749 and then Comes_From_Source (N)
750 and then Expander_Active
752 -- Any null that comes from source and is of the RAS type must
753 -- be expanded, except if expansion is not active (nothing
754 -- gets expanded into the equivalent record type).
756 Target_Type := Equivalent_Type (Typ);
758 elsif Ekind (Typ) = E_Record_Type
759 and then Present (Corresponding_Remote_Type (Typ))
761 -- This is a record type representing a RAS type, this must be
767 -- We do not have to handle this case
775 Component_Associations => New_List (
776 Make_Component_Association (Loc,
777 Choices => New_List (
778 Make_Identifier (Loc, Name_Ras)),
781 Analyze_And_Resolve (N, Target_Type);
783 end Remote_AST_Null_Value;