1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2006, 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_Res; use Sem_Res;
40 with Sem_Util; use Sem_Util;
41 with Sinfo; use Sinfo;
42 with Stand; use Stand;
43 with Stringt; use Stringt;
44 with Tbuild; use Tbuild;
46 package body Sem_Dist is
48 -----------------------
49 -- Local Subprograms --
50 -----------------------
52 procedure RAS_E_Dereference (Pref : Node_Id);
53 -- Handles explicit dereference of Remote Access to Subprograms
55 function Full_Qualified_Name (E : Entity_Id) return String_Id;
56 -- returns the full qualified name of the entity in lower case
58 -------------------------
59 -- Add_Stub_Constructs --
60 -------------------------
62 procedure Add_Stub_Constructs (N : Node_Id) is
63 U : constant Node_Id := Unit (N);
64 Spec : Entity_Id := Empty;
65 Exp : Node_Id := U; -- Unit that will be expanded
68 pragma Assert (Distribution_Stub_Mode /= No_Stubs);
70 if Nkind (U) = N_Package_Declaration then
71 Spec := Defining_Entity (Specification (U));
73 elsif Nkind (U) = N_Package_Body then
74 Spec := Corresponding_Spec (U);
76 else pragma Assert (Nkind (U) = N_Package_Instantiation);
77 Exp := Instance_Spec (U);
78 Spec := Defining_Entity (Specification (Exp));
81 pragma Assert (Is_Shared_Passive (Spec)
82 or else Is_Remote_Call_Interface (Spec));
84 if Distribution_Stub_Mode = Generate_Caller_Stub_Body then
86 if Is_Shared_Passive (Spec) then
88 elsif Nkind (U) = N_Package_Body then
90 ("Specification file expected from command line", U);
92 Expand_Calling_Stubs_Bodies (Exp);
97 if Is_Shared_Passive (Spec) then
98 Build_Passive_Partition_Stub (Exp);
100 Expand_Receiving_Stubs_Bodies (Exp);
104 end Add_Stub_Constructs;
106 ---------------------------------------
107 -- Build_RAS_Primitive_Specification --
108 ---------------------------------------
110 function Build_RAS_Primitive_Specification
111 (Subp_Spec : Node_Id;
112 Remote_Object_Type : Node_Id) return Node_Id
114 Loc : constant Source_Ptr := Sloc (Subp_Spec);
116 Primitive_Spec : constant Node_Id :=
117 Copy_Specification (Loc,
119 New_Name => Name_uCall);
121 Subtype_Mark_For_Self : Node_Id;
124 if No (Parameter_Specifications (Primitive_Spec)) then
125 Set_Parameter_Specifications (Primitive_Spec, New_List);
128 if Nkind (Remote_Object_Type) in N_Entity then
129 Subtype_Mark_For_Self :=
130 New_Occurrence_Of (Remote_Object_Type, Loc);
132 Subtype_Mark_For_Self := Remote_Object_Type;
136 Parameter_Specifications (Primitive_Spec),
137 Make_Parameter_Specification (Loc,
138 Defining_Identifier =>
139 Make_Defining_Identifier (Loc, Name_uS),
141 Make_Access_Definition (Loc,
143 Subtype_Mark_For_Self)));
145 -- Trick later semantic analysis into considering this operation as a
146 -- primitive (dispatching) operation of tagged type Obj_Type.
148 Set_Comes_From_Source (
149 Defining_Unit_Name (Primitive_Spec), True);
151 return Primitive_Spec;
152 end Build_RAS_Primitive_Specification;
154 -------------------------
155 -- Full_Qualified_Name --
156 -------------------------
158 function Full_Qualified_Name (E : Entity_Id) return String_Id is
159 Ent : Entity_Id := E;
160 Parent_Name : String_Id := No_String;
163 -- Deals properly with child units
165 if Nkind (Ent) = N_Defining_Program_Unit_Name then
166 Ent := Defining_Identifier (Ent);
169 -- Compute recursively the qualification (only "Standard" has no scope)
171 if Present (Scope (Scope (Ent))) then
172 Parent_Name := Full_Qualified_Name (Scope (Ent));
175 -- Every entity should have a name except some expanded blocks. Do not
176 -- bother about those.
178 if Chars (Ent) = No_Name then
182 -- Add a period between Name and qualification
184 if Parent_Name /= No_String then
185 Start_String (Parent_Name);
186 Store_String_Char (Get_Char_Code ('.'));
192 -- Generates the entity name in upper case
194 Get_Name_String (Chars (Ent));
195 Set_Casing (All_Lower_Case);
196 Store_String_Chars (Name_Buffer (1 .. Name_Len));
198 end Full_Qualified_Name;
204 function Get_PCS_Name return PCS_Names is
205 PCS_Name : constant PCS_Names :=
206 Chars (Entity (Expression
207 (Parent (RTE (RE_DSA_Implementation)))));
212 ------------------------
213 -- Is_All_Remote_Call --
214 ------------------------
216 function Is_All_Remote_Call (N : Node_Id) return Boolean is
220 if (Nkind (N) = N_Function_Call
221 or else Nkind (N) = N_Procedure_Call_Statement)
222 and then Nkind (Name (N)) in N_Has_Entity
223 and then Is_Remote_Call_Interface (Entity (Name (N)))
224 and then Has_All_Calls_Remote (Scope (Entity (Name (N))))
225 and then Comes_From_Source (N)
227 Par := Parent (Entity (Name (N)));
230 and then (Nkind (Par) /= N_Package_Specification
231 or else Is_Wrapper_Package (Defining_Entity (Par)))
236 if Present (Par) then
238 not Scope_Within_Or_Same (Current_Scope, Defining_Entity (Par));
245 end Is_All_Remote_Call;
247 ------------------------------------
248 -- Package_Specification_Of_Scope --
249 ------------------------------------
251 function Package_Specification_Of_Scope (E : Entity_Id) return Node_Id is
252 N : Node_Id := Parent (E);
254 while Nkind (N) /= N_Package_Specification loop
259 end Package_Specification_Of_Scope;
261 --------------------------
262 -- Process_Partition_ID --
263 --------------------------
265 procedure Process_Partition_Id (N : Node_Id) is
266 Loc : constant Source_Ptr := Sloc (N);
269 Get_Pt_Id_Call : Node_Id;
270 Prefix_String : String_Id;
271 Typ : constant Entity_Id := Etype (N);
274 Ety := Entity (Prefix (N));
276 -- In case prefix is not a library unit entity, get the entity
279 while (Present (Scope (Ety))
280 and then Scope (Ety) /= Standard_Standard)
281 and not Is_Child_Unit (Ety)
286 -- Retrieve the proper function to call
288 if Is_Remote_Call_Interface (Ety) then
289 Get_Pt_Id := New_Occurrence_Of
290 (RTE (RE_Get_Active_Partition_Id), Loc);
292 elsif Is_Shared_Passive (Ety) then
293 Get_Pt_Id := New_Occurrence_Of
294 (RTE (RE_Get_Passive_Partition_Id), Loc);
297 Get_Pt_Id := New_Occurrence_Of
298 (RTE (RE_Get_Local_Partition_Id), Loc);
301 -- Get and store the String_Id corresponding to the name of the
302 -- library unit whose Partition_Id is needed.
304 Get_Library_Unit_Name_String (Unit_Declaration_Node (Ety));
305 Prefix_String := String_From_Name_Buffer;
307 -- Build the function call which will replace the attribute
309 if Is_Remote_Call_Interface (Ety)
310 or else Is_Shared_Passive (Ety)
313 Make_Function_Call (Loc,
315 Parameter_Associations =>
316 New_List (Make_String_Literal (Loc, Prefix_String)));
319 Get_Pt_Id_Call := Make_Function_Call (Loc, Get_Pt_Id);
323 -- Replace the attribute node by a conversion of the function call
324 -- to the target type.
326 Rewrite (N, Convert_To (Typ, Get_Pt_Id_Call));
327 Analyze_And_Resolve (N, Typ);
328 end Process_Partition_Id;
330 ----------------------------------
331 -- Process_Remote_AST_Attribute --
332 ----------------------------------
334 procedure Process_Remote_AST_Attribute
336 New_Type : Entity_Id)
338 Loc : constant Source_Ptr := Sloc (N);
339 Remote_Subp : Entity_Id;
340 Tick_Access_Conv_Call : Node_Id;
341 Remote_Subp_Decl : Node_Id;
342 RS_Pkg_Specif : Node_Id;
343 RS_Pkg_E : Entity_Id;
344 RAS_Type : Entity_Id := New_Type;
346 All_Calls_Remote_E : Entity_Id;
347 Attribute_Subp : Entity_Id;
350 -- Check if we have to expand the access attribute
352 Remote_Subp := Entity (Prefix (N));
354 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
358 if Ekind (RAS_Type) /= E_Record_Type then
359 RAS_Type := Equivalent_Type (RAS_Type);
362 Attribute_Subp := TSS (RAS_Type, TSS_RAS_Access);
363 pragma Assert (Present (Attribute_Subp));
364 Remote_Subp_Decl := Unit_Declaration_Node (Remote_Subp);
366 if Nkind (Remote_Subp_Decl) = N_Subprogram_Body then
367 Remote_Subp := Corresponding_Spec (Remote_Subp_Decl);
368 Remote_Subp_Decl := Unit_Declaration_Node (Remote_Subp);
371 RS_Pkg_Specif := Parent (Remote_Subp_Decl);
372 RS_Pkg_E := Defining_Entity (RS_Pkg_Specif);
375 Boolean_Literals (Ekind (Remote_Subp) = E_Procedure
376 and then Is_Asynchronous (Remote_Subp));
378 All_Calls_Remote_E :=
379 Boolean_Literals (Has_All_Calls_Remote (RS_Pkg_E));
381 Tick_Access_Conv_Call :=
382 Make_Function_Call (Loc,
383 Name => New_Occurrence_Of (Attribute_Subp, Loc),
384 Parameter_Associations =>
386 Make_String_Literal (Loc, Full_Qualified_Name (RS_Pkg_E)),
387 Build_Subprogram_Id (Loc, Remote_Subp),
388 New_Occurrence_Of (Async_E, Loc),
389 New_Occurrence_Of (All_Calls_Remote_E, Loc)));
391 Rewrite (N, Tick_Access_Conv_Call);
392 Analyze_And_Resolve (N, RAS_Type);
393 end Process_Remote_AST_Attribute;
395 ------------------------------------
396 -- Process_Remote_AST_Declaration --
397 ------------------------------------
399 procedure Process_Remote_AST_Declaration (N : Node_Id) is
400 Loc : constant Source_Ptr := Sloc (N);
401 User_Type : constant Node_Id := Defining_Identifier (N);
402 Scop : constant Entity_Id := Scope (User_Type);
403 Is_RCI : constant Boolean := Is_Remote_Call_Interface (Scop);
404 Is_RT : constant Boolean := Is_Remote_Types (Scop);
405 Type_Def : constant Node_Id := Type_Definition (N);
408 Is_Degenerate : Boolean;
409 -- True iff this RAS has an access formal parameter (see
410 -- Exp_Dist.Add_RAS_Dereference_TSS for details).
412 Subpkg : constant Entity_Id :=
413 Make_Defining_Identifier (Loc,
414 New_Internal_Name ('S'));
415 Subpkg_Decl : Node_Id;
416 Subpkg_Body : Node_Id;
417 Vis_Decls : constant List_Id := New_List;
418 Priv_Decls : constant List_Id := New_List;
420 Obj_Type : constant Entity_Id :=
421 Make_Defining_Identifier (Loc,
422 New_External_Name (Chars (User_Type), 'R'));
424 Full_Obj_Type : constant Entity_Id :=
425 Make_Defining_Identifier (Loc,
428 RACW_Type : constant Entity_Id :=
429 Make_Defining_Identifier (Loc,
430 New_External_Name (Chars (User_Type), 'P'));
432 Fat_Type : constant Entity_Id :=
433 Make_Defining_Identifier (Loc,
436 Fat_Type_Decl : Node_Id;
439 Is_Degenerate := False;
440 Parameter := First (Parameter_Specifications (Type_Def));
441 while Present (Parameter) loop
442 if Nkind (Parameter_Type (Parameter)) = N_Access_Definition then
443 Error_Msg_N ("formal parameter& has anonymous access type?",
444 Defining_Identifier (Parameter));
445 Is_Degenerate := True;
452 if Is_Degenerate then
454 ("remote access-to-subprogram type& can only be null?",
455 Defining_Identifier (Parameter), User_Type);
457 -- The only legal value for a RAS with a formal parameter of an
458 -- anonymous access type is null, because it cannot be subtype-
459 -- conformant with any legal remote subprogram declaration. In this
460 -- case, we cannot generate a corresponding primitive operation.
464 if Get_PCS_Name = Name_No_DSA then
468 -- The tagged private type, primitive operation and RACW type associated
469 -- with a RAS need to all be declared in a subpackage of the one that
470 -- contains the RAS declaration, because the primitive of the object
471 -- type, and the associated primitive of the stub type, need to be
472 -- dispatching operations of these types, and the profile of the RAS
473 -- might contain tagged types declared in the same scope.
475 Append_To (Vis_Decls,
476 Make_Private_Type_Declaration (Loc,
477 Defining_Identifier => Obj_Type,
478 Abstract_Present => True,
479 Tagged_Present => True,
480 Limited_Present => True));
482 Append_To (Priv_Decls,
483 Make_Full_Type_Declaration (Loc,
484 Defining_Identifier =>
487 Make_Record_Definition (Loc,
488 Abstract_Present => True,
489 Tagged_Present => True,
490 Limited_Present => True,
491 Null_Present => True,
492 Component_List => Empty)));
494 -- Trick semantic analysis into swapping the public and full view when
495 -- freezing the public view.
497 Set_Comes_From_Source (Full_Obj_Type, True);
499 if not Is_Degenerate then
500 Append_To (Vis_Decls,
501 Make_Abstract_Subprogram_Declaration (Loc,
502 Specification => Build_RAS_Primitive_Specification (
503 Subp_Spec => Type_Def,
504 Remote_Object_Type => Obj_Type)));
507 Append_To (Vis_Decls,
508 Make_Full_Type_Declaration (Loc,
509 Defining_Identifier => RACW_Type,
511 Make_Access_To_Object_Definition (Loc,
513 Subtype_Indication =>
514 Make_Attribute_Reference (Loc,
516 New_Occurrence_Of (Obj_Type, Loc),
519 Set_Is_Remote_Call_Interface (RACW_Type, Is_RCI);
520 Set_Is_Remote_Types (RACW_Type, Is_RT);
523 Make_Package_Declaration (Loc,
524 Make_Package_Specification (Loc,
525 Defining_Unit_Name =>
527 Visible_Declarations =>
529 Private_Declarations =>
532 New_Occurrence_Of (Subpkg, Loc)));
533 Set_Is_Remote_Call_Interface (Subpkg, Is_RCI);
534 Set_Is_Remote_Types (Subpkg, Is_RT);
535 Insert_After_And_Analyze (N, Subpkg_Decl);
537 -- Generate package body to receive RACW calling stubs
538 -- Note: Analyze_Declarations has an absolute requirement that
539 -- the declaration list be non-empty, so we provide a dummy null
543 Make_Package_Body (Loc,
544 Defining_Unit_Name =>
545 Make_Defining_Identifier (Loc, Chars (Subpkg)),
546 Declarations => New_List (
547 Make_Null_Statement (Loc)));
548 Insert_After_And_Analyze (Subpkg_Decl, Subpkg_Body);
550 -- Many parts of the analyzer and expander expect
551 -- that the fat pointer type used to implement remote
552 -- access to subprogram types be a record.
553 -- Note: The structure of this type must be kept consistent
554 -- with the code generated by Remote_AST_Null_Value for the
555 -- corresponding 'null' expression.
557 Fat_Type_Decl := Make_Full_Type_Declaration (Loc,
558 Defining_Identifier => Fat_Type,
560 Make_Record_Definition (Loc,
562 Make_Component_List (Loc,
563 Component_Items => New_List (
564 Make_Component_Declaration (Loc,
565 Defining_Identifier =>
566 Make_Defining_Identifier (Loc, Name_Ras),
567 Component_Definition =>
568 Make_Component_Definition (Loc,
571 Subtype_Indication =>
572 New_Occurrence_Of (RACW_Type, Loc)))))));
573 Set_Equivalent_Type (User_Type, Fat_Type);
574 Set_Corresponding_Remote_Type (Fat_Type, User_Type);
575 Insert_After_And_Analyze (Subpkg_Body, Fat_Type_Decl);
577 -- The reason we suppress the initialization procedure is that we know
578 -- that no initialization is required (even if Initialize_Scalars mode
579 -- is active), and there are order of elaboration problems if we do try
580 -- to generate an init proc for this created record type.
582 Set_Suppress_Init_Proc (Fat_Type);
584 if Expander_Active then
585 Add_RAST_Features (Parent (User_Type));
587 end Process_Remote_AST_Declaration;
589 -----------------------
590 -- RAS_E_Dereference --
591 -----------------------
593 procedure RAS_E_Dereference (Pref : Node_Id) is
594 Loc : constant Source_Ptr := Sloc (Pref);
596 New_Type : constant Entity_Id := Etype (Pref);
597 Explicit_Deref : constant Node_Id := Parent (Pref);
598 Deref_Subp_Call : constant Node_Id := Parent (Explicit_Deref);
599 Deref_Proc : Entity_Id;
603 if Nkind (Deref_Subp_Call) = N_Procedure_Call_Statement then
604 Params := Parameter_Associations (Deref_Subp_Call);
606 if Present (Params) then
607 Prepend (Pref, Params);
609 Params := New_List (Pref);
612 elsif Nkind (Deref_Subp_Call) = N_Indexed_Component then
614 Params := Expressions (Deref_Subp_Call);
616 if Present (Params) then
617 Prepend (Pref, Params);
619 Params := New_List (Pref);
623 -- Context is not a call
628 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
632 Deref_Proc := TSS (New_Type, TSS_RAS_Dereference);
633 pragma Assert (Present (Deref_Proc));
635 if Ekind (Deref_Proc) = E_Function then
637 Make_Function_Call (Loc,
638 Name => New_Occurrence_Of (Deref_Proc, Loc),
639 Parameter_Associations => Params);
643 Make_Procedure_Call_Statement (Loc,
644 Name => New_Occurrence_Of (Deref_Proc, Loc),
645 Parameter_Associations => Params);
648 Rewrite (Deref_Subp_Call, Call_Node);
649 Analyze (Deref_Subp_Call);
650 end RAS_E_Dereference;
652 ------------------------------
653 -- Remote_AST_E_Dereference --
654 ------------------------------
656 function Remote_AST_E_Dereference (P : Node_Id) return Boolean is
657 ET : constant Entity_Id := Etype (P);
660 -- Perform the changes only on original dereferences, and only if
661 -- we are generating code.
663 if Comes_From_Source (P)
664 and then Is_Record_Type (ET)
665 and then (Is_Remote_Call_Interface (ET)
666 or else Is_Remote_Types (ET))
667 and then Present (Corresponding_Remote_Type (ET))
668 and then (Nkind (Parent (Parent (P))) = N_Procedure_Call_Statement
669 or else Nkind (Parent (Parent (P))) = N_Indexed_Component)
670 and then Expander_Active
672 RAS_E_Dereference (P);
677 end Remote_AST_E_Dereference;
679 ------------------------------
680 -- Remote_AST_I_Dereference --
681 ------------------------------
683 function Remote_AST_I_Dereference (P : Node_Id) return Boolean is
684 ET : constant Entity_Id := Etype (P);
688 if Comes_From_Source (P)
689 and then (Is_Remote_Call_Interface (ET)
690 or else Is_Remote_Types (ET))
691 and then Present (Corresponding_Remote_Type (ET))
692 and then Ekind (Entity (P)) /= E_Function
695 Make_Explicit_Dereference (Sloc (P),
696 Prefix => Relocate_Node (P));
699 RAS_E_Dereference (Prefix (P));
704 end Remote_AST_I_Dereference;
706 ---------------------------
707 -- Remote_AST_Null_Value --
708 ---------------------------
710 function Remote_AST_Null_Value
712 Typ : Entity_Id) return Boolean
714 Loc : constant Source_Ptr := Sloc (N);
715 Target_Type : Entity_Id;
718 if not Expander_Active or else Get_PCS_Name = Name_No_DSA then
721 elsif Ekind (Typ) = E_Access_Subprogram_Type
722 and then (Is_Remote_Call_Interface (Typ)
723 or else Is_Remote_Types (Typ))
724 and then Comes_From_Source (N)
725 and then Expander_Active
727 -- Any null that comes from source and is of the RAS type must
728 -- be expanded, except if expansion is not active (nothing
729 -- gets expanded into the equivalent record type).
731 Target_Type := Equivalent_Type (Typ);
733 elsif Ekind (Typ) = E_Record_Type
734 and then Present (Corresponding_Remote_Type (Typ))
736 -- This is a record type representing a RAS type, this must be
742 -- We do not have to handle this case
750 Component_Associations => New_List (
751 Make_Component_Association (Loc,
752 Choices => New_List (
753 Make_Identifier (Loc, Name_Ras)),
756 Analyze_And_Resolve (N, Target_Type);
758 end Remote_AST_Null_Value;