* arm.c (FL_WBUF): Define.
[official-gcc.git] / gcc / ada / exp_ch9.adb
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1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- E X P _ C H 9 --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2005, Free Software Foundation, Inc. --
10 -- --
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. --
21 -- --
22 -- GNAT was originally developed by the GNAT team at New York University. --
23 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 -- --
25 ------------------------------------------------------------------------------
27 with Atree; use Atree;
28 with Checks; use Checks;
29 with Einfo; use Einfo;
30 with Elists; use Elists;
31 with Errout; use Errout;
32 with Exp_Ch3; use Exp_Ch3;
33 with Exp_Ch11; use Exp_Ch11;
34 with Exp_Ch6; use Exp_Ch6;
35 with Exp_Dbug; use Exp_Dbug;
36 with Exp_Smem; use Exp_Smem;
37 with Exp_Tss; use Exp_Tss;
38 with Exp_Util; use Exp_Util;
39 with Freeze; use Freeze;
40 with Hostparm;
41 with Namet; use Namet;
42 with Nlists; use Nlists;
43 with Nmake; use Nmake;
44 with Opt; use Opt;
45 with Restrict; use Restrict;
46 with Rident; use Rident;
47 with Rtsfind; use Rtsfind;
48 with Sem; use Sem;
49 with Sem_Ch6;
50 with Sem_Ch8; use Sem_Ch8;
51 with Sem_Ch11; use Sem_Ch11;
52 with Sem_Elab; use Sem_Elab;
53 with Sem_Res; use Sem_Res;
54 with Sem_Util; use Sem_Util;
55 with Sinfo; use Sinfo;
56 with Snames; use Snames;
57 with Stand; use Stand;
58 with Targparm; use Targparm;
59 with Tbuild; use Tbuild;
60 with Types; use Types;
61 with Uintp; use Uintp;
63 package body Exp_Ch9 is
65 -----------------------
66 -- Local Subprograms --
67 -----------------------
69 function Actual_Index_Expression
70 (Sloc : Source_Ptr;
71 Ent : Entity_Id;
72 Index : Node_Id;
73 Tsk : Entity_Id) return Node_Id;
74 -- Compute the index position for an entry call. Tsk is the target
75 -- task. If the bounds of some entry family depend on discriminants,
76 -- the expression computed by this function uses the discriminants
77 -- of the target task.
79 function Index_Constant_Declaration
80 (N : Node_Id;
81 Index_Id : Entity_Id;
82 Prot : Entity_Id) return List_Id;
83 -- For an entry family and its barrier function, we define a local entity
84 -- that maps the index in the call into the entry index into the object:
86 -- I : constant Index_Type := Index_Type'Val (
87 -- E - <<index of first family member>> +
88 -- Protected_Entry_Index (Index_Type'Pos (Index_Type'First)));
90 procedure Add_Object_Pointer
91 (Decls : List_Id;
92 Pid : Entity_Id;
93 Loc : Source_Ptr);
94 -- Prepend an object pointer declaration to the declaration list
95 -- Decls. This object pointer is initialized to a type conversion
96 -- of the System.Address pointer passed to entry barrier functions
97 -- and entry body procedures.
99 function Build_Accept_Body (Astat : Node_Id) return Node_Id;
100 -- Transform accept statement into a block with added exception handler.
101 -- Used both for simple accept statements and for accept alternatives in
102 -- select statements. Astat is the accept statement.
104 function Build_Barrier_Function
105 (N : Node_Id;
106 Ent : Entity_Id;
107 Pid : Node_Id) return Node_Id;
108 -- Build the function body returning the value of the barrier expression
109 -- for the specified entry body.
111 function Build_Barrier_Function_Specification
112 (Def_Id : Entity_Id;
113 Loc : Source_Ptr) return Node_Id;
114 -- Build a specification for a function implementing
115 -- the protected entry barrier of the specified entry body.
117 function Build_Corresponding_Record
118 (N : Node_Id;
119 Ctyp : Node_Id;
120 Loc : Source_Ptr) return Node_Id;
121 -- Common to tasks and protected types. Copy discriminant specifications,
122 -- build record declaration. N is the type declaration, Ctyp is the
123 -- concurrent entity (task type or protected type).
125 function Build_Entry_Count_Expression
126 (Concurrent_Type : Node_Id;
127 Component_List : List_Id;
128 Loc : Source_Ptr) return Node_Id;
129 -- Compute number of entries for concurrent object. This is a count of
130 -- simple entries, followed by an expression that computes the length
131 -- of the range of each entry family. A single array with that size is
132 -- allocated for each concurrent object of the type.
134 function Build_Find_Body_Index (Typ : Entity_Id) return Node_Id;
135 -- Build the function that translates the entry index in the call
136 -- (which depends on the size of entry families) into an index into the
137 -- Entry_Bodies_Array, to determine the body and barrier function used
138 -- in a protected entry call. A pointer to this function appears in every
139 -- protected object.
141 function Build_Find_Body_Index_Spec (Typ : Entity_Id) return Node_Id;
142 -- Build subprogram declaration for previous one
144 function Build_Protected_Entry
145 (N : Node_Id;
146 Ent : Entity_Id;
147 Pid : Node_Id) return Node_Id;
148 -- Build the procedure implementing the statement sequence of
149 -- the specified entry body.
151 function Build_Protected_Entry_Specification
152 (Def_Id : Entity_Id;
153 Ent_Id : Entity_Id;
154 Loc : Source_Ptr) return Node_Id;
155 -- Build a specification for a procedure implementing
156 -- the statement sequence of the specified entry body.
157 -- Add attributes associating it with the entry defining identifier
158 -- Ent_Id.
160 function Build_Protected_Subprogram_Body
161 (N : Node_Id;
162 Pid : Node_Id;
163 N_Op_Spec : Node_Id) return Node_Id;
164 -- This function is used to construct the protected version of a protected
165 -- subprogram. Its statement sequence first defers abort, then locks
166 -- the associated protected object, and then enters a block that contains
167 -- a call to the unprotected version of the subprogram (for details, see
168 -- Build_Unprotected_Subprogram_Body). This block statement requires
169 -- a cleanup handler that unlocks the object in all cases.
170 -- (see Exp_Ch7.Expand_Cleanup_Actions).
172 function Build_Protected_Spec
173 (N : Node_Id;
174 Obj_Type : Entity_Id;
175 Unprotected : Boolean := False;
176 Ident : Entity_Id) return List_Id;
177 -- Utility shared by Build_Protected_Sub_Spec and Expand_Access_Protected_
178 -- Subprogram_Type. Builds signature of protected subprogram, adding the
179 -- formal that corresponds to the object itself. For an access to protected
180 -- subprogram, there is no object type to specify, so the additional
181 -- parameter has type Address and mode In. An indirect call through such
182 -- a pointer converts the address to a reference to the actual object.
183 -- The object is a limited record and therefore a by_reference type.
185 function Build_Selected_Name
186 (Prefix, Selector : Name_Id;
187 Append_Char : Character := ' ') return Name_Id;
188 -- Build a name in the form of Prefix__Selector, with an optional
189 -- character appended. This is used for internal subprograms generated
190 -- for operations of protected types, including barrier functions.
191 -- For the subprograms generated for entry bodies and entry barriers,
192 -- the generated name includes a sequence number that makes names
193 -- unique in the presence of entry overloading. This is necessary
194 -- because entry body procedures and barrier functions all have the
195 -- same signature.
197 procedure Build_Simple_Entry_Call
198 (N : Node_Id;
199 Concval : Node_Id;
200 Ename : Node_Id;
201 Index : Node_Id);
202 -- Some comments here would be useful ???
204 function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id;
205 -- This routine constructs a specification for the procedure that we will
206 -- build for the task body for task type T. The spec has the form:
208 -- procedure tnameB (_Task : access tnameV);
210 -- where name is the character name taken from the task type entity that
211 -- is passed as the argument to the procedure, and tnameV is the task
212 -- value type that is associated with the task type.
214 function Build_Unprotected_Subprogram_Body
215 (N : Node_Id;
216 Pid : Node_Id) return Node_Id;
217 -- This routine constructs the unprotected version of a protected
218 -- subprogram body, which is contains all of the code in the
219 -- original, unexpanded body. This is the version of the protected
220 -- subprogram that is called from all protected operations on the same
221 -- object, including the protected version of the same subprogram.
223 procedure Collect_Entry_Families
224 (Loc : Source_Ptr;
225 Cdecls : List_Id;
226 Current_Node : in out Node_Id;
227 Conctyp : Entity_Id);
228 -- For each entry family in a concurrent type, create an anonymous array
229 -- type of the right size, and add a component to the corresponding_record.
231 function Family_Offset
232 (Loc : Source_Ptr;
233 Hi : Node_Id;
234 Lo : Node_Id;
235 Ttyp : Entity_Id) return Node_Id;
236 -- Compute (Hi - Lo) for two entry family indices. Hi is the index in
237 -- an accept statement, or the upper bound in the discrete subtype of
238 -- an entry declaration. Lo is the corresponding lower bound. Ttyp is
239 -- the concurrent type of the entry.
241 function Family_Size
242 (Loc : Source_Ptr;
243 Hi : Node_Id;
244 Lo : Node_Id;
245 Ttyp : Entity_Id) return Node_Id;
246 -- Compute (Hi - Lo) + 1 Max 0, to determine the number of entries in
247 -- a family, and handle properly the superflat case. This is equivalent
248 -- to the use of 'Length on the index type, but must use Family_Offset
249 -- to handle properly the case of bounds that depend on discriminants.
251 procedure Extract_Entry
252 (N : Node_Id;
253 Concval : out Node_Id;
254 Ename : out Node_Id;
255 Index : out Node_Id);
256 -- Given an entry call, returns the associated concurrent object,
257 -- the entry name, and the entry family index.
259 function Find_Task_Or_Protected_Pragma
260 (T : Node_Id;
261 P : Name_Id) return Node_Id;
262 -- Searches the task or protected definition T for the first occurrence
263 -- of the pragma whose name is given by P. The caller has ensured that
264 -- the pragma is present in the task definition. A special case is that
265 -- when P is Name_uPriority, the call will also find Interrupt_Priority.
266 -- ??? Should be implemented with the rep item chain mechanism.
268 procedure Update_Prival_Subtypes (N : Node_Id);
269 -- The actual subtypes of the privals will differ from the type of the
270 -- private declaration in the original protected type, if the protected
271 -- type has discriminants or if the prival has constrained components.
272 -- This is because the privals are generated out of sequence w.r.t. the
273 -- analysis of a protected body. After generating the bodies for protected
274 -- operations, we set correctly the type of all references to privals, by
275 -- means of a recursive tree traversal, which is heavy-handed but
276 -- correct.
278 -----------------------------
279 -- Actual_Index_Expression --
280 -----------------------------
282 function Actual_Index_Expression
283 (Sloc : Source_Ptr;
284 Ent : Entity_Id;
285 Index : Node_Id;
286 Tsk : Entity_Id) return Node_Id
288 Ttyp : constant Entity_Id := Etype (Tsk);
289 Expr : Node_Id;
290 Num : Node_Id;
291 Lo : Node_Id;
292 Hi : Node_Id;
293 Prev : Entity_Id;
294 S : Node_Id;
296 function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id;
297 -- Compute difference between bounds of entry family
299 --------------------------
300 -- Actual_Family_Offset --
301 --------------------------
303 function Actual_Family_Offset (Hi, Lo : Node_Id) return Node_Id is
305 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id;
306 -- Replace a reference to a discriminant with a selected component
307 -- denoting the discriminant of the target task.
309 -----------------------------
310 -- Actual_Discriminant_Ref --
311 -----------------------------
313 function Actual_Discriminant_Ref (Bound : Node_Id) return Node_Id is
314 Typ : constant Entity_Id := Etype (Bound);
315 B : Node_Id;
317 begin
318 if not Is_Entity_Name (Bound)
319 or else Ekind (Entity (Bound)) /= E_Discriminant
320 then
321 if Nkind (Bound) = N_Attribute_Reference then
322 return Bound;
323 else
324 B := New_Copy_Tree (Bound);
325 end if;
327 else
328 B :=
329 Make_Selected_Component (Sloc,
330 Prefix => New_Copy_Tree (Tsk),
331 Selector_Name => New_Occurrence_Of (Entity (Bound), Sloc));
333 Analyze_And_Resolve (B, Typ);
334 end if;
336 return
337 Make_Attribute_Reference (Sloc,
338 Attribute_Name => Name_Pos,
339 Prefix => New_Occurrence_Of (Etype (Bound), Sloc),
340 Expressions => New_List (B));
341 end Actual_Discriminant_Ref;
343 -- Start of processing for Actual_Family_Offset
345 begin
346 return
347 Make_Op_Subtract (Sloc,
348 Left_Opnd => Actual_Discriminant_Ref (Hi),
349 Right_Opnd => Actual_Discriminant_Ref (Lo));
350 end Actual_Family_Offset;
352 -- Start of processing for Actual_Index_Expression
354 begin
355 -- The queues of entries and entry families appear in textual
356 -- order in the associated record. The entry index is computed as
357 -- the sum of the number of queues for all entries that precede the
358 -- designated one, to which is added the index expression, if this
359 -- expression denotes a member of a family.
361 -- The following is a place holder for the count of simple entries
363 Num := Make_Integer_Literal (Sloc, 1);
365 -- We construct an expression which is a series of addition
366 -- operations. See comments in Entry_Index_Expression, which is
367 -- identical in structure.
369 if Present (Index) then
370 S := Etype (Discrete_Subtype_Definition (Declaration_Node (Ent)));
372 Expr :=
373 Make_Op_Add (Sloc,
374 Left_Opnd => Num,
376 Right_Opnd =>
377 Actual_Family_Offset (
378 Make_Attribute_Reference (Sloc,
379 Attribute_Name => Name_Pos,
380 Prefix => New_Reference_To (Base_Type (S), Sloc),
381 Expressions => New_List (Relocate_Node (Index))),
382 Type_Low_Bound (S)));
383 else
384 Expr := Num;
385 end if;
387 -- Now add lengths of preceding entries and entry families
389 Prev := First_Entity (Ttyp);
391 while Chars (Prev) /= Chars (Ent)
392 or else (Ekind (Prev) /= Ekind (Ent))
393 or else not Sem_Ch6.Type_Conformant (Ent, Prev)
394 loop
395 if Ekind (Prev) = E_Entry then
396 Set_Intval (Num, Intval (Num) + 1);
398 elsif Ekind (Prev) = E_Entry_Family then
399 S :=
400 Etype (Discrete_Subtype_Definition (Declaration_Node (Prev)));
401 Lo := Type_Low_Bound (S);
402 Hi := Type_High_Bound (S);
404 Expr :=
405 Make_Op_Add (Sloc,
406 Left_Opnd => Expr,
407 Right_Opnd =>
408 Make_Op_Add (Sloc,
409 Left_Opnd =>
410 Actual_Family_Offset (Hi, Lo),
411 Right_Opnd =>
412 Make_Integer_Literal (Sloc, 1)));
414 -- Other components are anonymous types to be ignored
416 else
417 null;
418 end if;
420 Next_Entity (Prev);
421 end loop;
423 return Expr;
424 end Actual_Index_Expression;
426 ----------------------------------
427 -- Add_Discriminal_Declarations --
428 ----------------------------------
430 procedure Add_Discriminal_Declarations
431 (Decls : List_Id;
432 Typ : Entity_Id;
433 Name : Name_Id;
434 Loc : Source_Ptr)
436 D : Entity_Id;
438 begin
439 if Has_Discriminants (Typ) then
440 D := First_Discriminant (Typ);
442 while Present (D) loop
444 Prepend_To (Decls,
445 Make_Object_Renaming_Declaration (Loc,
446 Defining_Identifier => Discriminal (D),
447 Subtype_Mark => New_Reference_To (Etype (D), Loc),
448 Name =>
449 Make_Selected_Component (Loc,
450 Prefix => Make_Identifier (Loc, Name),
451 Selector_Name => Make_Identifier (Loc, Chars (D)))));
453 Next_Discriminant (D);
454 end loop;
455 end if;
456 end Add_Discriminal_Declarations;
458 ------------------------
459 -- Add_Object_Pointer --
460 ------------------------
462 procedure Add_Object_Pointer
463 (Decls : List_Id;
464 Pid : Entity_Id;
465 Loc : Source_Ptr)
467 Obj_Ptr : Node_Id;
469 begin
470 -- Prepend the declaration of _object. This must be first in the
471 -- declaration list, since it is used by the discriminal and
472 -- prival declarations.
473 -- ??? An attempt to make this a renaming was unsuccessful.
475 -- type poVP is access poV;
476 -- _object : poVP := poVP!O;
478 Obj_Ptr :=
479 Make_Defining_Identifier (Loc,
480 Chars =>
481 New_External_Name
482 (Chars (Corresponding_Record_Type (Pid)), 'P'));
484 Prepend_To (Decls,
485 Make_Object_Declaration (Loc,
486 Defining_Identifier =>
487 Make_Defining_Identifier (Loc, Name_uObject),
488 Object_Definition => New_Reference_To (Obj_Ptr, Loc),
489 Expression =>
490 Unchecked_Convert_To (Obj_Ptr,
491 Make_Identifier (Loc, Name_uO))));
493 Prepend_To (Decls,
494 Make_Full_Type_Declaration (Loc,
495 Defining_Identifier => Obj_Ptr,
496 Type_Definition => Make_Access_To_Object_Definition (Loc,
497 Subtype_Indication =>
498 New_Reference_To (Corresponding_Record_Type (Pid), Loc))));
499 end Add_Object_Pointer;
501 ------------------------------
502 -- Add_Private_Declarations --
503 ------------------------------
505 procedure Add_Private_Declarations
506 (Decls : List_Id;
507 Typ : Entity_Id;
508 Name : Name_Id;
509 Loc : Source_Ptr)
511 Def : constant Node_Id := Protected_Definition (Parent (Typ));
512 Body_Ent : constant Entity_Id := Corresponding_Body (Parent (Typ));
513 P : Node_Id;
514 Pdef : Entity_Id;
516 begin
517 pragma Assert (Nkind (Def) = N_Protected_Definition);
519 if Present (Private_Declarations (Def)) then
520 P := First (Private_Declarations (Def));
522 while Present (P) loop
523 if Nkind (P) = N_Component_Declaration then
524 Pdef := Defining_Identifier (P);
525 Prepend_To (Decls,
526 Make_Object_Renaming_Declaration (Loc,
527 Defining_Identifier => Prival (Pdef),
528 Subtype_Mark => New_Reference_To (Etype (Pdef), Loc),
529 Name =>
530 Make_Selected_Component (Loc,
531 Prefix => Make_Identifier (Loc, Name),
532 Selector_Name => Make_Identifier (Loc, Chars (Pdef)))));
533 end if;
534 Next (P);
535 end loop;
536 end if;
538 -- One more "prival" for the object itself, with the right protection
539 -- type.
541 declare
542 Protection_Type : RE_Id;
543 begin
544 if Has_Attach_Handler (Typ) then
545 if Restricted_Profile then
546 if Has_Entries (Typ) then
547 Protection_Type := RE_Protection_Entry;
548 else
549 Protection_Type := RE_Protection;
550 end if;
551 else
552 Protection_Type := RE_Static_Interrupt_Protection;
553 end if;
555 elsif Has_Interrupt_Handler (Typ) then
556 Protection_Type := RE_Dynamic_Interrupt_Protection;
558 elsif Has_Entries (Typ) then
559 if Abort_Allowed
560 or else Restriction_Active (No_Entry_Queue) = False
561 or else Number_Entries (Typ) > 1
562 then
563 Protection_Type := RE_Protection_Entries;
564 else
565 Protection_Type := RE_Protection_Entry;
566 end if;
568 else
569 Protection_Type := RE_Protection;
570 end if;
572 Prepend_To (Decls,
573 Make_Object_Renaming_Declaration (Loc,
574 Defining_Identifier => Object_Ref (Body_Ent),
575 Subtype_Mark => New_Reference_To (RTE (Protection_Type), Loc),
576 Name =>
577 Make_Selected_Component (Loc,
578 Prefix => Make_Identifier (Loc, Name),
579 Selector_Name => Make_Identifier (Loc, Name_uObject))));
580 end;
581 end Add_Private_Declarations;
583 -----------------------
584 -- Build_Accept_Body --
585 -----------------------
587 function Build_Accept_Body (Astat : Node_Id) return Node_Id is
588 Loc : constant Source_Ptr := Sloc (Astat);
589 Stats : constant Node_Id := Handled_Statement_Sequence (Astat);
590 New_S : Node_Id;
591 Hand : Node_Id;
592 Call : Node_Id;
593 Ohandle : Node_Id;
595 begin
596 -- At the end of the statement sequence, Complete_Rendezvous is called.
597 -- A label skipping the Complete_Rendezvous, and all other
598 -- accept processing, has already been added for the expansion
599 -- of requeue statements.
601 Call := Build_Runtime_Call (Loc, RE_Complete_Rendezvous);
602 Insert_Before (Last (Statements (Stats)), Call);
603 Analyze (Call);
605 -- If exception handlers are present, then append Complete_Rendezvous
606 -- calls to the handlers, and construct the required outer block.
608 if Present (Exception_Handlers (Stats)) then
609 Hand := First (Exception_Handlers (Stats));
611 while Present (Hand) loop
612 Call := Build_Runtime_Call (Loc, RE_Complete_Rendezvous);
613 Append (Call, Statements (Hand));
614 Analyze (Call);
615 Next (Hand);
616 end loop;
618 New_S :=
619 Make_Handled_Sequence_Of_Statements (Loc,
620 Statements => New_List (
621 Make_Block_Statement (Loc,
622 Handled_Statement_Sequence => Stats)));
624 else
625 New_S := Stats;
626 end if;
628 -- At this stage we know that the new statement sequence does not
629 -- have an exception handler part, so we supply one to call
630 -- Exceptional_Complete_Rendezvous. This handler is
632 -- when all others =>
633 -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
635 -- We handle Abort_Signal to make sure that we properly catch the abort
636 -- case and wake up the caller.
638 Ohandle := Make_Others_Choice (Loc);
639 Set_All_Others (Ohandle);
641 Set_Exception_Handlers (New_S,
642 New_List (
643 Make_Exception_Handler (Loc,
644 Exception_Choices => New_List (Ohandle),
646 Statements => New_List (
647 Make_Procedure_Call_Statement (Loc,
648 Name => New_Reference_To (
649 RTE (RE_Exceptional_Complete_Rendezvous), Loc),
650 Parameter_Associations => New_List (
651 Make_Function_Call (Loc,
652 Name => New_Reference_To (
653 RTE (RE_Get_GNAT_Exception), Loc))))))));
655 Set_Parent (New_S, Astat); -- temp parent for Analyze call
656 Analyze_Exception_Handlers (Exception_Handlers (New_S));
657 Expand_Exception_Handlers (New_S);
659 -- Exceptional_Complete_Rendezvous must be called with abort
660 -- still deferred, which is the case for a "when all others" handler.
662 return New_S;
663 end Build_Accept_Body;
665 -----------------------------------
666 -- Build_Activation_Chain_Entity --
667 -----------------------------------
669 procedure Build_Activation_Chain_Entity (N : Node_Id) is
670 P : Node_Id;
671 B : Node_Id;
672 Decls : List_Id;
674 begin
675 -- Loop to find enclosing construct containing activation chain variable
677 P := Parent (N);
679 while Nkind (P) /= N_Subprogram_Body
680 and then Nkind (P) /= N_Package_Declaration
681 and then Nkind (P) /= N_Package_Body
682 and then Nkind (P) /= N_Block_Statement
683 and then Nkind (P) /= N_Task_Body
684 loop
685 P := Parent (P);
686 end loop;
688 -- If we are in a package body, the activation chain variable is
689 -- allocated in the corresponding spec. First, we save the package
690 -- body node because we enter the new entity in its Declarations list.
692 B := P;
694 if Nkind (P) = N_Package_Body then
695 P := Unit_Declaration_Node (Corresponding_Spec (P));
696 Decls := Declarations (B);
698 elsif Nkind (P) = N_Package_Declaration then
699 Decls := Visible_Declarations (Specification (B));
701 else
702 Decls := Declarations (B);
703 end if;
705 -- If activation chain entity not already declared, declare it
707 if No (Activation_Chain_Entity (P)) then
708 Set_Activation_Chain_Entity
709 (P, Make_Defining_Identifier (Sloc (N), Name_uChain));
711 Prepend_To (Decls,
712 Make_Object_Declaration (Sloc (P),
713 Defining_Identifier => Activation_Chain_Entity (P),
714 Aliased_Present => True,
715 Object_Definition =>
716 New_Reference_To (RTE (RE_Activation_Chain), Sloc (P))));
718 Analyze (First (Decls));
719 end if;
720 end Build_Activation_Chain_Entity;
722 ----------------------------
723 -- Build_Barrier_Function --
724 ----------------------------
726 function Build_Barrier_Function
727 (N : Node_Id;
728 Ent : Entity_Id;
729 Pid : Node_Id) return Node_Id
731 Loc : constant Source_Ptr := Sloc (N);
732 Ent_Formals : constant Node_Id := Entry_Body_Formal_Part (N);
733 Index_Spec : constant Node_Id := Entry_Index_Specification
734 (Ent_Formals);
735 Op_Decls : constant List_Id := New_List;
736 Bdef : Entity_Id;
737 Bspec : Node_Id;
739 begin
740 Bdef :=
741 Make_Defining_Identifier (Loc, Chars (Barrier_Function (Ent)));
742 Bspec := Build_Barrier_Function_Specification (Bdef, Loc);
744 -- <object pointer declaration>
745 -- <discriminant renamings>
746 -- <private object renamings>
747 -- Add discriminal and private renamings. These names have
748 -- already been used to expand references to discriminants
749 -- and private data.
751 Add_Discriminal_Declarations (Op_Decls, Pid, Name_uObject, Loc);
752 Add_Private_Declarations (Op_Decls, Pid, Name_uObject, Loc);
753 Add_Object_Pointer (Op_Decls, Pid, Loc);
755 -- If this is the barrier for an entry family, the entry index is
756 -- visible in the body of the barrier. Create a local variable that
757 -- converts the entry index (which is the last formal of the barrier
758 -- function) into the appropriate offset into the entry array. The
759 -- entry index constant must be set, as for the entry body, so that
760 -- local references to the entry index are correctly replaced with
761 -- the local variable. This parallels what is done for entry bodies.
763 if Present (Index_Spec) then
764 declare
765 Index_Id : constant Entity_Id := Defining_Identifier (Index_Spec);
766 Index_Con : constant Entity_Id :=
767 Make_Defining_Identifier (Loc,
768 Chars => New_Internal_Name ('J'));
770 begin
771 Set_Entry_Index_Constant (Index_Id, Index_Con);
772 Append_List_To (Op_Decls,
773 Index_Constant_Declaration (N, Index_Id, Pid));
774 end;
775 end if;
777 -- Note: the condition in the barrier function needs to be properly
778 -- processed for the C/Fortran boolean possibility, but this happens
779 -- automatically since the return statement does this normalization.
781 return
782 Make_Subprogram_Body (Loc,
783 Specification => Bspec,
784 Declarations => Op_Decls,
785 Handled_Statement_Sequence =>
786 Make_Handled_Sequence_Of_Statements (Loc,
787 Statements => New_List (
788 Make_Return_Statement (Loc,
789 Expression => Condition (Ent_Formals)))));
790 end Build_Barrier_Function;
792 ------------------------------------------
793 -- Build_Barrier_Function_Specification --
794 ------------------------------------------
796 function Build_Barrier_Function_Specification
797 (Def_Id : Entity_Id;
798 Loc : Source_Ptr) return Node_Id
800 begin
801 Set_Needs_Debug_Info (Def_Id);
802 return Make_Function_Specification (Loc,
803 Defining_Unit_Name => Def_Id,
804 Parameter_Specifications => New_List (
805 Make_Parameter_Specification (Loc,
806 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uO),
807 Parameter_Type =>
808 New_Reference_To (RTE (RE_Address), Loc)),
810 Make_Parameter_Specification (Loc,
811 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uE),
812 Parameter_Type =>
813 New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))),
815 Subtype_Mark => New_Reference_To (Standard_Boolean, Loc));
816 end Build_Barrier_Function_Specification;
818 --------------------------
819 -- Build_Call_With_Task --
820 --------------------------
822 function Build_Call_With_Task
823 (N : Node_Id;
824 E : Entity_Id) return Node_Id
826 Loc : constant Source_Ptr := Sloc (N);
828 begin
829 return
830 Make_Function_Call (Loc,
831 Name => New_Reference_To (E, Loc),
832 Parameter_Associations => New_List (Concurrent_Ref (N)));
833 end Build_Call_With_Task;
835 --------------------------------
836 -- Build_Corresponding_Record --
837 --------------------------------
839 function Build_Corresponding_Record
840 (N : Node_Id;
841 Ctyp : Entity_Id;
842 Loc : Source_Ptr) return Node_Id
844 Rec_Ent : constant Entity_Id :=
845 Make_Defining_Identifier
846 (Loc, New_External_Name (Chars (Ctyp), 'V'));
847 Disc : Entity_Id;
848 Dlist : List_Id;
849 New_Disc : Entity_Id;
850 Cdecls : List_Id;
852 begin
853 Set_Corresponding_Record_Type (Ctyp, Rec_Ent);
854 Set_Ekind (Rec_Ent, E_Record_Type);
855 Set_Has_Delayed_Freeze (Rec_Ent, Has_Delayed_Freeze (Ctyp));
856 Set_Is_Concurrent_Record_Type (Rec_Ent, True);
857 Set_Corresponding_Concurrent_Type (Rec_Ent, Ctyp);
858 Set_Stored_Constraint (Rec_Ent, No_Elist);
859 Cdecls := New_List;
861 -- Use discriminals to create list of discriminants for record, and
862 -- create new discriminals for use in default expressions, etc. It is
863 -- worth noting that a task discriminant gives rise to 5 entities;
865 -- a) The original discriminant.
866 -- b) The discriminal for use in the task.
867 -- c) The discriminant of the corresponding record.
868 -- d) The discriminal for the init proc of the corresponding record.
869 -- e) The local variable that renames the discriminant in the procedure
870 -- for the task body.
872 -- In fact the discriminals b) are used in the renaming declarations
873 -- for e). See details in einfo (Handling of Discriminants).
875 if Present (Discriminant_Specifications (N)) then
876 Dlist := New_List;
877 Disc := First_Discriminant (Ctyp);
879 while Present (Disc) loop
880 New_Disc := CR_Discriminant (Disc);
882 Append_To (Dlist,
883 Make_Discriminant_Specification (Loc,
884 Defining_Identifier => New_Disc,
885 Discriminant_Type =>
886 New_Occurrence_Of (Etype (Disc), Loc),
887 Expression =>
888 New_Copy (Discriminant_Default_Value (Disc))));
890 Next_Discriminant (Disc);
891 end loop;
893 else
894 Dlist := No_List;
895 end if;
897 -- Now we can construct the record type declaration. Note that this
898 -- record is limited, reflecting the underlying limitedness of the
899 -- task or protected object that it represents, and ensuring for
900 -- example that it is properly passed by reference.
902 return
903 Make_Full_Type_Declaration (Loc,
904 Defining_Identifier => Rec_Ent,
905 Discriminant_Specifications => Dlist,
906 Type_Definition =>
907 Make_Record_Definition (Loc,
908 Component_List =>
909 Make_Component_List (Loc,
910 Component_Items => Cdecls),
911 Limited_Present => True));
912 end Build_Corresponding_Record;
914 ----------------------------------
915 -- Build_Entry_Count_Expression --
916 ----------------------------------
918 function Build_Entry_Count_Expression
919 (Concurrent_Type : Node_Id;
920 Component_List : List_Id;
921 Loc : Source_Ptr) return Node_Id
923 Eindx : Nat;
924 Ent : Entity_Id;
925 Ecount : Node_Id;
926 Comp : Node_Id;
927 Lo : Node_Id;
928 Hi : Node_Id;
929 Typ : Entity_Id;
931 begin
932 Ent := First_Entity (Concurrent_Type);
933 Eindx := 0;
935 -- Count number of non-family entries
937 while Present (Ent) loop
938 if Ekind (Ent) = E_Entry then
939 Eindx := Eindx + 1;
940 end if;
942 Next_Entity (Ent);
943 end loop;
945 Ecount := Make_Integer_Literal (Loc, Eindx);
947 -- Loop through entry families building the addition nodes
949 Ent := First_Entity (Concurrent_Type);
950 Comp := First (Component_List);
952 while Present (Ent) loop
953 if Ekind (Ent) = E_Entry_Family then
954 while Chars (Ent) /= Chars (Defining_Identifier (Comp)) loop
955 Next (Comp);
956 end loop;
958 Typ := Etype (Discrete_Subtype_Definition (Parent (Ent)));
959 Hi := Type_High_Bound (Typ);
960 Lo := Type_Low_Bound (Typ);
962 Ecount :=
963 Make_Op_Add (Loc,
964 Left_Opnd => Ecount,
965 Right_Opnd => Family_Size (Loc, Hi, Lo, Concurrent_Type));
966 end if;
968 Next_Entity (Ent);
969 end loop;
971 return Ecount;
972 end Build_Entry_Count_Expression;
974 ---------------------------
975 -- Build_Find_Body_Index --
976 ---------------------------
978 function Build_Find_Body_Index (Typ : Entity_Id) return Node_Id is
979 Loc : constant Source_Ptr := Sloc (Typ);
980 Ent : Entity_Id;
981 E_Typ : Entity_Id;
982 Has_F : Boolean := False;
983 Index : Nat;
984 If_St : Node_Id := Empty;
985 Lo : Node_Id;
986 Hi : Node_Id;
987 Decls : List_Id := New_List;
988 Ret : Node_Id;
989 Spec : Node_Id;
990 Siz : Node_Id := Empty;
992 procedure Add_If_Clause (Expr : Node_Id);
993 -- Add test for range of current entry
995 function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id;
996 -- If a bound of an entry is given by a discriminant, retrieve the
997 -- actual value of the discriminant from the enclosing object.
999 -------------------
1000 -- Add_If_Clause --
1001 -------------------
1003 procedure Add_If_Clause (Expr : Node_Id) is
1004 Cond : Node_Id;
1005 Stats : constant List_Id :=
1006 New_List (
1007 Make_Return_Statement (Loc,
1008 Expression => Make_Integer_Literal (Loc, Index + 1)));
1010 begin
1011 -- Index for current entry body
1013 Index := Index + 1;
1015 -- Compute total length of entry queues so far
1017 if No (Siz) then
1018 Siz := Expr;
1019 else
1020 Siz :=
1021 Make_Op_Add (Loc,
1022 Left_Opnd => Siz,
1023 Right_Opnd => Expr);
1024 end if;
1026 Cond :=
1027 Make_Op_Le (Loc,
1028 Left_Opnd => Make_Identifier (Loc, Name_uE),
1029 Right_Opnd => Siz);
1031 -- Map entry queue indices in the range of the current family
1032 -- into the current index, that designates the entry body.
1034 if No (If_St) then
1035 If_St :=
1036 Make_Implicit_If_Statement (Typ,
1037 Condition => Cond,
1038 Then_Statements => Stats,
1039 Elsif_Parts => New_List);
1041 Ret := If_St;
1043 else
1044 Append (
1045 Make_Elsif_Part (Loc,
1046 Condition => Cond,
1047 Then_Statements => Stats),
1048 Elsif_Parts (If_St));
1049 end if;
1050 end Add_If_Clause;
1052 ------------------------------
1053 -- Convert_Discriminant_Ref --
1054 ------------------------------
1056 function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is
1057 B : Node_Id;
1059 begin
1060 if Is_Entity_Name (Bound)
1061 and then Ekind (Entity (Bound)) = E_Discriminant
1062 then
1063 B :=
1064 Make_Selected_Component (Loc,
1065 Prefix =>
1066 Unchecked_Convert_To (Corresponding_Record_Type (Typ),
1067 Make_Explicit_Dereference (Loc,
1068 Make_Identifier (Loc, Name_uObject))),
1069 Selector_Name => Make_Identifier (Loc, Chars (Bound)));
1070 Set_Etype (B, Etype (Entity (Bound)));
1071 else
1072 B := New_Copy_Tree (Bound);
1073 end if;
1075 return B;
1076 end Convert_Discriminant_Ref;
1078 -- Start of processing for Build_Find_Body_Index
1080 begin
1081 Spec := Build_Find_Body_Index_Spec (Typ);
1083 Ent := First_Entity (Typ);
1085 while Present (Ent) loop
1087 if Ekind (Ent) = E_Entry_Family then
1088 Has_F := True;
1089 exit;
1090 end if;
1092 Next_Entity (Ent);
1093 end loop;
1095 if not Has_F then
1097 -- If the protected type has no entry families, there is a one-one
1098 -- correspondence between entry queue and entry body.
1100 Ret :=
1101 Make_Return_Statement (Loc,
1102 Expression => Make_Identifier (Loc, Name_uE));
1104 else
1105 -- Suppose entries e1, e2, ... have size l1, l2, ... we generate
1106 -- the following:
1108 -- if E <= l1 then return 1;
1109 -- elsif E <= l1 + l2 then return 2;
1110 -- ...
1112 Index := 0;
1113 Siz := Empty;
1114 Ent := First_Entity (Typ);
1116 Add_Object_Pointer (Decls, Typ, Loc);
1118 while Present (Ent) loop
1120 if Ekind (Ent) = E_Entry then
1121 Add_If_Clause (Make_Integer_Literal (Loc, 1));
1123 elsif Ekind (Ent) = E_Entry_Family then
1125 E_Typ := Etype (Discrete_Subtype_Definition (Parent (Ent)));
1126 Hi := Convert_Discriminant_Ref (Type_High_Bound (E_Typ));
1127 Lo := Convert_Discriminant_Ref (Type_Low_Bound (E_Typ));
1128 Add_If_Clause (Family_Size (Loc, Hi, Lo, Typ));
1129 end if;
1131 Next_Entity (Ent);
1132 end loop;
1134 if Index = 1 then
1135 Decls := New_List;
1136 Ret :=
1137 Make_Return_Statement (Loc,
1138 Expression => Make_Integer_Literal (Loc, 1));
1140 elsif Nkind (Ret) = N_If_Statement then
1142 -- Ranges are in increasing order, so last one doesn't need a
1143 -- guard.
1145 declare
1146 Nod : constant Node_Id := Last (Elsif_Parts (Ret));
1148 begin
1149 Remove (Nod);
1150 Set_Else_Statements (Ret, Then_Statements (Nod));
1151 end;
1152 end if;
1153 end if;
1155 return
1156 Make_Subprogram_Body (Loc,
1157 Specification => Spec,
1158 Declarations => Decls,
1159 Handled_Statement_Sequence =>
1160 Make_Handled_Sequence_Of_Statements (Loc,
1161 Statements => New_List (Ret)));
1162 end Build_Find_Body_Index;
1164 --------------------------------
1165 -- Build_Find_Body_Index_Spec --
1166 --------------------------------
1168 function Build_Find_Body_Index_Spec (Typ : Entity_Id) return Node_Id is
1169 Loc : constant Source_Ptr := Sloc (Typ);
1170 Id : constant Entity_Id :=
1171 Make_Defining_Identifier (Loc,
1172 Chars => New_External_Name (Chars (Typ), 'F'));
1173 Parm1 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uO);
1174 Parm2 : constant Entity_Id := Make_Defining_Identifier (Loc, Name_uE);
1176 begin
1177 return
1178 Make_Function_Specification (Loc,
1179 Defining_Unit_Name => Id,
1180 Parameter_Specifications => New_List (
1181 Make_Parameter_Specification (Loc,
1182 Defining_Identifier => Parm1,
1183 Parameter_Type =>
1184 New_Reference_To (RTE (RE_Address), Loc)),
1186 Make_Parameter_Specification (Loc,
1187 Defining_Identifier => Parm2,
1188 Parameter_Type =>
1189 New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))),
1190 Subtype_Mark => New_Occurrence_Of (
1191 RTE (RE_Protected_Entry_Index), Loc));
1192 end Build_Find_Body_Index_Spec;
1194 -------------------------
1195 -- Build_Master_Entity --
1196 -------------------------
1198 procedure Build_Master_Entity (E : Entity_Id) is
1199 Loc : constant Source_Ptr := Sloc (E);
1200 P : Node_Id;
1201 Decl : Node_Id;
1202 S : Entity_Id;
1204 begin
1205 S := Scope (E);
1207 -- Ada 2005 (AI-287): Do not set/get the has_master_entity reminder
1208 -- in internal scopes. Required for nested limited aggregates.
1210 if Ada_Version >= Ada_05 then
1211 while Is_Internal (S) loop
1212 S := Scope (S);
1213 end loop;
1214 end if;
1216 -- Nothing to do if we already built a master entity for this scope
1217 -- or if there is no task hierarchy.
1219 if Has_Master_Entity (S)
1220 or else Restriction_Active (No_Task_Hierarchy)
1221 then
1222 return;
1223 end if;
1225 -- Otherwise first build the master entity
1226 -- _Master : constant Master_Id := Current_Master.all;
1227 -- and insert it just before the current declaration
1229 Decl :=
1230 Make_Object_Declaration (Loc,
1231 Defining_Identifier =>
1232 Make_Defining_Identifier (Loc, Name_uMaster),
1233 Constant_Present => True,
1234 Object_Definition => New_Reference_To (RTE (RE_Master_Id), Loc),
1235 Expression =>
1236 Make_Explicit_Dereference (Loc,
1237 New_Reference_To (RTE (RE_Current_Master), Loc)));
1239 P := Parent (E);
1240 Insert_Before (P, Decl);
1241 Analyze (Decl);
1243 -- Ada 2005 (AI-287): Set the has_master_entity reminder in the
1244 -- non-internal scope selected above.
1246 if Ada_Version >= Ada_05 then
1247 Set_Has_Master_Entity (S);
1248 else
1249 Set_Has_Master_Entity (Scope (E));
1250 end if;
1252 -- Now mark the containing scope as a task master
1254 while Nkind (P) /= N_Compilation_Unit loop
1255 P := Parent (P);
1257 -- If we fall off the top, we are at the outer level, and the
1258 -- environment task is our effective master, so nothing to mark.
1260 if Nkind (P) = N_Task_Body
1261 or else Nkind (P) = N_Block_Statement
1262 or else Nkind (P) = N_Subprogram_Body
1263 then
1264 Set_Is_Task_Master (P, True);
1265 return;
1267 elsif Nkind (Parent (P)) = N_Subunit then
1268 P := Corresponding_Stub (Parent (P));
1269 end if;
1270 end loop;
1271 end Build_Master_Entity;
1273 ---------------------------
1274 -- Build_Protected_Entry --
1275 ---------------------------
1277 function Build_Protected_Entry
1278 (N : Node_Id;
1279 Ent : Entity_Id;
1280 Pid : Node_Id) return Node_Id
1282 Loc : constant Source_Ptr := Sloc (N);
1283 Op_Decls : constant List_Id := New_List;
1284 Edef : Entity_Id;
1285 Espec : Node_Id;
1286 Op_Stats : List_Id;
1287 Ohandle : Node_Id;
1288 Complete : Node_Id;
1290 begin
1291 Edef :=
1292 Make_Defining_Identifier (Loc,
1293 Chars => Chars (Protected_Body_Subprogram (Ent)));
1294 Espec := Build_Protected_Entry_Specification (Edef, Empty, Loc);
1296 -- <object pointer declaration>
1297 -- Add object pointer declaration. This is needed by the
1298 -- discriminal and prival renamings, which should already
1299 -- have been inserted into the declaration list.
1301 Add_Object_Pointer (Op_Decls, Pid, Loc);
1303 if Abort_Allowed
1304 or else Restriction_Active (No_Entry_Queue) = False
1305 or else Number_Entries (Pid) > 1
1306 then
1307 Complete := New_Reference_To (RTE (RE_Complete_Entry_Body), Loc);
1308 else
1309 Complete :=
1310 New_Reference_To (RTE (RE_Complete_Single_Entry_Body), Loc);
1311 end if;
1313 Op_Stats := New_List (
1314 Make_Block_Statement (Loc,
1315 Declarations => Declarations (N),
1316 Handled_Statement_Sequence =>
1317 Handled_Statement_Sequence (N)),
1319 Make_Procedure_Call_Statement (Loc,
1320 Name => Complete,
1321 Parameter_Associations => New_List (
1322 Make_Attribute_Reference (Loc,
1323 Prefix =>
1324 Make_Selected_Component (Loc,
1325 Prefix =>
1326 Make_Identifier (Loc, Name_uObject),
1328 Selector_Name =>
1329 Make_Identifier (Loc, Name_uObject)),
1330 Attribute_Name => Name_Unchecked_Access))));
1332 if Restriction_Active (No_Exception_Handlers) then
1333 return
1334 Make_Subprogram_Body (Loc,
1335 Specification => Espec,
1336 Declarations => Op_Decls,
1337 Handled_Statement_Sequence =>
1338 Make_Handled_Sequence_Of_Statements (Loc, Op_Stats));
1340 else
1341 Ohandle := Make_Others_Choice (Loc);
1342 Set_All_Others (Ohandle);
1344 if Abort_Allowed
1345 or else Restriction_Active (No_Entry_Queue) = False
1346 or else Number_Entries (Pid) > 1
1347 then
1348 Complete :=
1349 New_Reference_To (RTE (RE_Exceptional_Complete_Entry_Body), Loc);
1351 else
1352 Complete := New_Reference_To (
1353 RTE (RE_Exceptional_Complete_Single_Entry_Body), Loc);
1354 end if;
1356 return
1357 Make_Subprogram_Body (Loc,
1358 Specification => Espec,
1359 Declarations => Op_Decls,
1360 Handled_Statement_Sequence =>
1361 Make_Handled_Sequence_Of_Statements (Loc,
1362 Statements => Op_Stats,
1363 Exception_Handlers => New_List (
1364 Make_Exception_Handler (Loc,
1365 Exception_Choices => New_List (Ohandle),
1367 Statements => New_List (
1368 Make_Procedure_Call_Statement (Loc,
1369 Name => Complete,
1370 Parameter_Associations => New_List (
1371 Make_Attribute_Reference (Loc,
1372 Prefix =>
1373 Make_Selected_Component (Loc,
1374 Prefix =>
1375 Make_Identifier (Loc, Name_uObject),
1376 Selector_Name =>
1377 Make_Identifier (Loc, Name_uObject)),
1378 Attribute_Name => Name_Unchecked_Access),
1380 Make_Function_Call (Loc,
1381 Name => New_Reference_To (
1382 RTE (RE_Get_GNAT_Exception), Loc)))))))));
1383 end if;
1384 end Build_Protected_Entry;
1386 -----------------------------------------
1387 -- Build_Protected_Entry_Specification --
1388 -----------------------------------------
1390 function Build_Protected_Entry_Specification
1391 (Def_Id : Entity_Id;
1392 Ent_Id : Entity_Id;
1393 Loc : Source_Ptr) return Node_Id
1395 P : Entity_Id;
1397 begin
1398 Set_Needs_Debug_Info (Def_Id);
1399 P := Make_Defining_Identifier (Loc, Name_uP);
1401 if Present (Ent_Id) then
1402 Append_Elmt (P, Accept_Address (Ent_Id));
1403 end if;
1405 return Make_Procedure_Specification (Loc,
1406 Defining_Unit_Name => Def_Id,
1407 Parameter_Specifications => New_List (
1408 Make_Parameter_Specification (Loc,
1409 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uO),
1410 Parameter_Type =>
1411 New_Reference_To (RTE (RE_Address), Loc)),
1413 Make_Parameter_Specification (Loc,
1414 Defining_Identifier => P,
1415 Parameter_Type =>
1416 New_Reference_To (RTE (RE_Address), Loc)),
1418 Make_Parameter_Specification (Loc,
1419 Defining_Identifier => Make_Defining_Identifier (Loc, Name_uE),
1420 Parameter_Type =>
1421 New_Reference_To (RTE (RE_Protected_Entry_Index), Loc))));
1422 end Build_Protected_Entry_Specification;
1424 --------------------------
1425 -- Build_Protected_Spec --
1426 --------------------------
1428 function Build_Protected_Spec
1429 (N : Node_Id;
1430 Obj_Type : Entity_Id;
1431 Unprotected : Boolean := False;
1432 Ident : Entity_Id) return List_Id
1434 Loc : constant Source_Ptr := Sloc (N);
1435 Formal : Entity_Id;
1436 New_Plist : List_Id;
1437 New_Param : Node_Id;
1439 begin
1440 New_Plist := New_List;
1441 Formal := First_Formal (Ident);
1443 while Present (Formal) loop
1444 New_Param :=
1445 Make_Parameter_Specification (Loc,
1446 Defining_Identifier =>
1447 Make_Defining_Identifier (Sloc (Formal), Chars (Formal)),
1448 In_Present => In_Present (Parent (Formal)),
1449 Out_Present => Out_Present (Parent (Formal)),
1450 Parameter_Type =>
1451 New_Reference_To (Etype (Formal), Loc));
1453 if Unprotected then
1454 Set_Protected_Formal (Formal, Defining_Identifier (New_Param));
1455 end if;
1457 Append (New_Param, New_Plist);
1458 Next_Formal (Formal);
1459 end loop;
1461 -- If the subprogram is a procedure and the context is not an access
1462 -- to protected subprogram, the parameter is in-out. Otherwise it is
1463 -- an in parameter.
1465 Prepend_To (New_Plist,
1466 Make_Parameter_Specification (Loc,
1467 Defining_Identifier =>
1468 Make_Defining_Identifier (Loc, Name_uObject),
1469 In_Present => True,
1470 Out_Present =>
1471 (Etype (Ident) = Standard_Void_Type
1472 and then not Is_RTE (Obj_Type, RE_Address)),
1473 Parameter_Type => New_Reference_To (Obj_Type, Loc)));
1475 return New_Plist;
1476 end Build_Protected_Spec;
1478 ---------------------------------------
1479 -- Build_Protected_Sub_Specification --
1480 ---------------------------------------
1482 function Build_Protected_Sub_Specification
1483 (N : Node_Id;
1484 Prottyp : Entity_Id;
1485 Unprotected : Boolean := False) return Node_Id
1487 Loc : constant Source_Ptr := Sloc (N);
1488 Decl : Node_Id;
1489 Protnm : constant Name_Id := Chars (Prottyp);
1490 Ident : Entity_Id;
1491 Nam : Name_Id;
1492 New_Id : Entity_Id;
1493 New_Plist : List_Id;
1494 Append_Char : Character;
1495 New_Spec : Node_Id;
1497 begin
1498 if Ekind
1499 (Defining_Unit_Name (Specification (N))) = E_Subprogram_Body
1500 then
1501 Decl := Unit_Declaration_Node (Corresponding_Spec (N));
1502 else
1503 Decl := N;
1504 end if;
1506 Ident := Defining_Unit_Name (Specification (Decl));
1507 Nam := Chars (Ident);
1509 New_Plist := Build_Protected_Spec
1510 (Decl, Corresponding_Record_Type (Prottyp),
1511 Unprotected, Ident);
1513 if Unprotected then
1514 Append_Char := 'N';
1515 else
1516 Append_Char := 'P';
1517 end if;
1519 New_Id :=
1520 Make_Defining_Identifier (Loc,
1521 Chars => Build_Selected_Name (Protnm, Nam, Append_Char));
1523 -- The unprotected operation carries the user code, and debugging
1524 -- information must be generated for it, even though this spec does
1525 -- not come from source. It is also convenient to allow gdb to step
1526 -- into the protected operation, even though it only contains lock/
1527 -- unlock calls.
1529 Set_Needs_Debug_Info (New_Id);
1531 if Nkind (Specification (Decl)) = N_Procedure_Specification then
1532 return
1533 Make_Procedure_Specification (Loc,
1534 Defining_Unit_Name => New_Id,
1535 Parameter_Specifications => New_Plist);
1537 else
1538 New_Spec :=
1539 Make_Function_Specification (Loc,
1540 Defining_Unit_Name => New_Id,
1541 Parameter_Specifications => New_Plist,
1542 Subtype_Mark => New_Copy (Subtype_Mark (Specification (Decl))));
1543 Set_Return_Present (Defining_Unit_Name (New_Spec));
1544 return New_Spec;
1545 end if;
1546 end Build_Protected_Sub_Specification;
1548 -------------------------------------
1549 -- Build_Protected_Subprogram_Body --
1550 -------------------------------------
1552 function Build_Protected_Subprogram_Body
1553 (N : Node_Id;
1554 Pid : Node_Id;
1555 N_Op_Spec : Node_Id) return Node_Id
1557 Loc : constant Source_Ptr := Sloc (N);
1558 Op_Spec : Node_Id;
1559 P_Op_Spec : Node_Id;
1560 Uactuals : List_Id;
1561 Pformal : Node_Id;
1562 Unprot_Call : Node_Id;
1563 Sub_Body : Node_Id;
1564 Lock_Name : Node_Id;
1565 Lock_Stmt : Node_Id;
1566 Service_Name : Node_Id;
1567 R : Node_Id;
1568 Return_Stmt : Node_Id := Empty; -- init to avoid gcc 3 warning
1569 Pre_Stmts : List_Id := No_List; -- init to avoid gcc 3 warning
1570 Stmts : List_Id;
1571 Object_Parm : Node_Id;
1572 Exc_Safe : Boolean;
1574 function Is_Exception_Safe (Subprogram : Node_Id) return Boolean;
1575 -- Tell whether a given subprogram cannot raise an exception
1577 -----------------------
1578 -- Is_Exception_Safe --
1579 -----------------------
1581 function Is_Exception_Safe (Subprogram : Node_Id) return Boolean is
1583 function Has_Side_Effect (N : Node_Id) return Boolean;
1584 -- Return True whenever encountering a subprogram call or a
1585 -- raise statement of any kind in the sequence of statements N
1587 ---------------------
1588 -- Has_Side_Effect --
1589 ---------------------
1591 -- What is this doing buried two levels down in exp_ch9. It
1592 -- seems like a generally useful function, and indeed there
1593 -- may be code duplication going on here ???
1595 function Has_Side_Effect (N : Node_Id) return Boolean is
1596 Stmt : Node_Id := N;
1597 Expr : Node_Id;
1599 function Is_Call_Or_Raise (N : Node_Id) return Boolean;
1600 -- Indicate whether N is a subprogram call or a raise statement
1602 function Is_Call_Or_Raise (N : Node_Id) return Boolean is
1603 begin
1604 return Nkind (N) = N_Procedure_Call_Statement
1605 or else Nkind (N) = N_Function_Call
1606 or else Nkind (N) = N_Raise_Statement
1607 or else Nkind (N) = N_Raise_Constraint_Error
1608 or else Nkind (N) = N_Raise_Program_Error
1609 or else Nkind (N) = N_Raise_Storage_Error;
1610 end Is_Call_Or_Raise;
1612 -- Start of processing for Has_Side_Effect
1614 begin
1615 while Present (Stmt) loop
1616 if Is_Call_Or_Raise (Stmt) then
1617 return True;
1618 end if;
1620 -- An object declaration can also contain a function call
1621 -- or a raise statement
1623 if Nkind (Stmt) = N_Object_Declaration then
1624 Expr := Expression (Stmt);
1626 if Present (Expr) and then Is_Call_Or_Raise (Expr) then
1627 return True;
1628 end if;
1629 end if;
1631 Next (Stmt);
1632 end loop;
1634 return False;
1635 end Has_Side_Effect;
1637 -- Start of processing for Is_Exception_Safe
1639 begin
1640 -- If the checks handled by the back end are not disabled, we cannot
1641 -- ensure that no exception will be raised.
1643 if not Access_Checks_Suppressed (Empty)
1644 or else not Discriminant_Checks_Suppressed (Empty)
1645 or else not Range_Checks_Suppressed (Empty)
1646 or else not Index_Checks_Suppressed (Empty)
1647 or else Opt.Stack_Checking_Enabled
1648 then
1649 return False;
1650 end if;
1652 if Has_Side_Effect (First (Declarations (Subprogram)))
1653 or else
1654 Has_Side_Effect (
1655 First (Statements (Handled_Statement_Sequence (Subprogram))))
1656 then
1657 return False;
1658 else
1659 return True;
1660 end if;
1661 end Is_Exception_Safe;
1663 -- Start of processing for Build_Protected_Subprogram_Body
1665 begin
1666 Op_Spec := Specification (N);
1667 Exc_Safe := Is_Exception_Safe (N);
1669 P_Op_Spec :=
1670 Build_Protected_Sub_Specification (N,
1671 Pid, Unprotected => False);
1673 -- Build a list of the formal parameters of the protected
1674 -- version of the subprogram to use as the actual parameters
1675 -- of the unprotected version.
1677 Uactuals := New_List;
1678 Pformal := First (Parameter_Specifications (P_Op_Spec));
1680 while Present (Pformal) loop
1681 Append (
1682 Make_Identifier (Loc, Chars (Defining_Identifier (Pformal))),
1683 Uactuals);
1684 Next (Pformal);
1685 end loop;
1687 -- Make a call to the unprotected version of the subprogram
1688 -- built above for use by the protected version built below.
1690 if Nkind (Op_Spec) = N_Function_Specification then
1691 if Exc_Safe then
1692 R := Make_Defining_Identifier (Loc, New_Internal_Name ('R'));
1693 Unprot_Call :=
1694 Make_Object_Declaration (Loc,
1695 Defining_Identifier => R,
1696 Constant_Present => True,
1697 Object_Definition => New_Copy (Subtype_Mark (N_Op_Spec)),
1698 Expression =>
1699 Make_Function_Call (Loc,
1700 Name => Make_Identifier (Loc,
1701 Chars (Defining_Unit_Name (N_Op_Spec))),
1702 Parameter_Associations => Uactuals));
1703 Return_Stmt := Make_Return_Statement (Loc,
1704 Expression => New_Reference_To (R, Loc));
1706 else
1707 Unprot_Call := Make_Return_Statement (Loc,
1708 Expression => Make_Function_Call (Loc,
1709 Name =>
1710 Make_Identifier (Loc,
1711 Chars (Defining_Unit_Name (N_Op_Spec))),
1712 Parameter_Associations => Uactuals));
1713 end if;
1715 else
1716 Unprot_Call := Make_Procedure_Call_Statement (Loc,
1717 Name =>
1718 Make_Identifier (Loc,
1719 Chars (Defining_Unit_Name (N_Op_Spec))),
1720 Parameter_Associations => Uactuals);
1721 end if;
1723 -- Wrap call in block that will be covered by an at_end handler
1725 if not Exc_Safe then
1726 Unprot_Call := Make_Block_Statement (Loc,
1727 Handled_Statement_Sequence =>
1728 Make_Handled_Sequence_Of_Statements (Loc,
1729 Statements => New_List (Unprot_Call)));
1730 end if;
1732 -- Make the protected subprogram body. This locks the protected
1733 -- object and calls the unprotected version of the subprogram.
1735 -- If the protected object is controlled (i.e it has entries or
1736 -- needs finalization for interrupt handling), call Lock_Entries,
1737 -- except if the protected object follows the Ravenscar profile, in
1738 -- which case call Lock_Entry, otherwise call the simplified version,
1739 -- Lock.
1741 if Has_Entries (Pid)
1742 or else Has_Interrupt_Handler (Pid)
1743 or else (Has_Attach_Handler (Pid) and then not Restricted_Profile)
1744 then
1745 if Abort_Allowed
1746 or else Restriction_Active (No_Entry_Queue) = False
1747 or else Number_Entries (Pid) > 1
1748 then
1749 Lock_Name := New_Reference_To (RTE (RE_Lock_Entries), Loc);
1750 Service_Name := New_Reference_To (RTE (RE_Service_Entries), Loc);
1752 else
1753 Lock_Name := New_Reference_To (RTE (RE_Lock_Entry), Loc);
1754 Service_Name := New_Reference_To (RTE (RE_Service_Entry), Loc);
1755 end if;
1757 else
1758 Lock_Name := New_Reference_To (RTE (RE_Lock), Loc);
1759 Service_Name := New_Reference_To (RTE (RE_Unlock), Loc);
1760 end if;
1762 Object_Parm :=
1763 Make_Attribute_Reference (Loc,
1764 Prefix =>
1765 Make_Selected_Component (Loc,
1766 Prefix =>
1767 Make_Identifier (Loc, Name_uObject),
1768 Selector_Name =>
1769 Make_Identifier (Loc, Name_uObject)),
1770 Attribute_Name => Name_Unchecked_Access);
1772 Lock_Stmt := Make_Procedure_Call_Statement (Loc,
1773 Name => Lock_Name,
1774 Parameter_Associations => New_List (Object_Parm));
1776 if Abort_Allowed then
1777 Stmts := New_List (
1778 Make_Procedure_Call_Statement (Loc,
1779 Name => New_Reference_To (RTE (RE_Abort_Defer), Loc),
1780 Parameter_Associations => Empty_List),
1781 Lock_Stmt);
1783 else
1784 Stmts := New_List (Lock_Stmt);
1785 end if;
1787 if not Exc_Safe then
1788 Append (Unprot_Call, Stmts);
1789 else
1790 if Nkind (Op_Spec) = N_Function_Specification then
1791 Pre_Stmts := Stmts;
1792 Stmts := Empty_List;
1793 else
1794 Append (Unprot_Call, Stmts);
1795 end if;
1797 Append (
1798 Make_Procedure_Call_Statement (Loc,
1799 Name => Service_Name,
1800 Parameter_Associations =>
1801 New_List (New_Copy_Tree (Object_Parm))),
1802 Stmts);
1804 if Abort_Allowed then
1805 Append (
1806 Make_Procedure_Call_Statement (Loc,
1807 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc),
1808 Parameter_Associations => Empty_List),
1809 Stmts);
1810 end if;
1812 if Nkind (Op_Spec) = N_Function_Specification then
1813 Append (Return_Stmt, Stmts);
1814 Append (Make_Block_Statement (Loc,
1815 Declarations => New_List (Unprot_Call),
1816 Handled_Statement_Sequence =>
1817 Make_Handled_Sequence_Of_Statements (Loc,
1818 Statements => Stmts)), Pre_Stmts);
1819 Stmts := Pre_Stmts;
1820 end if;
1821 end if;
1823 Sub_Body :=
1824 Make_Subprogram_Body (Loc,
1825 Declarations => Empty_List,
1826 Specification => P_Op_Spec,
1827 Handled_Statement_Sequence =>
1828 Make_Handled_Sequence_Of_Statements (Loc, Statements => Stmts));
1830 if not Exc_Safe then
1831 Set_Is_Protected_Subprogram_Body (Sub_Body);
1832 end if;
1834 return Sub_Body;
1835 end Build_Protected_Subprogram_Body;
1837 -------------------------------------
1838 -- Build_Protected_Subprogram_Call --
1839 -------------------------------------
1841 procedure Build_Protected_Subprogram_Call
1842 (N : Node_Id;
1843 Name : Node_Id;
1844 Rec : Node_Id;
1845 External : Boolean := True)
1847 Loc : constant Source_Ptr := Sloc (N);
1848 Sub : constant Entity_Id := Entity (Name);
1849 New_Sub : Node_Id;
1850 Params : List_Id;
1852 begin
1853 if External then
1854 New_Sub := New_Occurrence_Of (External_Subprogram (Sub), Loc);
1855 else
1856 New_Sub :=
1857 New_Occurrence_Of (Protected_Body_Subprogram (Sub), Loc);
1858 end if;
1860 if Present (Parameter_Associations (N)) then
1861 Params := New_Copy_List_Tree (Parameter_Associations (N));
1862 else
1863 Params := New_List;
1864 end if;
1866 Prepend (Rec, Params);
1868 if Ekind (Sub) = E_Procedure then
1869 Rewrite (N,
1870 Make_Procedure_Call_Statement (Loc,
1871 Name => New_Sub,
1872 Parameter_Associations => Params));
1874 else
1875 pragma Assert (Ekind (Sub) = E_Function);
1876 Rewrite (N,
1877 Make_Function_Call (Loc,
1878 Name => New_Sub,
1879 Parameter_Associations => Params));
1880 end if;
1882 if External
1883 and then Nkind (Rec) = N_Unchecked_Type_Conversion
1884 and then Is_Entity_Name (Expression (Rec))
1885 and then Is_Shared_Passive (Entity (Expression (Rec)))
1886 then
1887 Add_Shared_Var_Lock_Procs (N);
1888 end if;
1889 end Build_Protected_Subprogram_Call;
1891 -------------------------
1892 -- Build_Selected_Name --
1893 -------------------------
1895 function Build_Selected_Name
1896 (Prefix, Selector : Name_Id;
1897 Append_Char : Character := ' ') return Name_Id
1899 Select_Buffer : String (1 .. Hostparm.Max_Name_Length);
1900 Select_Len : Natural;
1902 begin
1903 Get_Name_String (Selector);
1904 Select_Len := Name_Len;
1905 Select_Buffer (1 .. Select_Len) := Name_Buffer (1 .. Name_Len);
1906 Get_Name_String (Prefix);
1908 -- If scope is anonymous type, discard suffix to recover name of
1909 -- single protected object. Otherwise use protected type name.
1911 if Name_Buffer (Name_Len) = 'T' then
1912 Name_Len := Name_Len - 1;
1913 end if;
1915 Name_Buffer (Name_Len + 1) := '_';
1916 Name_Buffer (Name_Len + 2) := '_';
1918 Name_Len := Name_Len + 2;
1919 for J in 1 .. Select_Len loop
1920 Name_Len := Name_Len + 1;
1921 Name_Buffer (Name_Len) := Select_Buffer (J);
1922 end loop;
1924 if Append_Char /= ' ' then
1925 Name_Len := Name_Len + 1;
1926 Name_Buffer (Name_Len) := Append_Char;
1927 end if;
1929 return Name_Find;
1930 end Build_Selected_Name;
1932 -----------------------------
1933 -- Build_Simple_Entry_Call --
1934 -----------------------------
1936 -- A task entry call is converted to a call to Call_Simple
1938 -- declare
1939 -- P : parms := (parm, parm, parm);
1940 -- begin
1941 -- Call_Simple (acceptor-task, entry-index, P'Address);
1942 -- parm := P.param;
1943 -- parm := P.param;
1944 -- ...
1945 -- end;
1947 -- Here Pnn is an aggregate of the type constructed for the entry to hold
1948 -- the parameters, and the constructed aggregate value contains either the
1949 -- parameters or, in the case of non-elementary types, references to these
1950 -- parameters. Then the address of this aggregate is passed to the runtime
1951 -- routine, along with the task id value and the task entry index value.
1952 -- Pnn is only required if parameters are present.
1954 -- The assignments after the call are present only in the case of in-out
1955 -- or out parameters for elementary types, and are used to assign back the
1956 -- resulting values of such parameters.
1958 -- Note: the reason that we insert a block here is that in the context
1959 -- of selects, conditional entry calls etc. the entry call statement
1960 -- appears on its own, not as an element of a list.
1962 -- A protected entry call is converted to a Protected_Entry_Call:
1964 -- declare
1965 -- P : E1_Params := (param, param, param);
1966 -- Pnn : Boolean;
1967 -- Bnn : Communications_Block;
1969 -- declare
1970 -- P : E1_Params := (param, param, param);
1971 -- Bnn : Communications_Block;
1973 -- begin
1974 -- Protected_Entry_Call (
1975 -- Object => po._object'Access,
1976 -- E => <entry index>;
1977 -- Uninterpreted_Data => P'Address;
1978 -- Mode => Simple_Call;
1979 -- Block => Bnn);
1980 -- parm := P.param;
1981 -- parm := P.param;
1982 -- ...
1983 -- end;
1985 procedure Build_Simple_Entry_Call
1986 (N : Node_Id;
1987 Concval : Node_Id;
1988 Ename : Node_Id;
1989 Index : Node_Id)
1991 begin
1992 Expand_Call (N);
1994 -- Convert entry call to Call_Simple call
1996 declare
1997 Loc : constant Source_Ptr := Sloc (N);
1998 Parms : constant List_Id := Parameter_Associations (N);
1999 Stats : constant List_Id := New_List;
2000 Pdecl : Node_Id;
2001 Xdecl : Node_Id;
2002 Decls : List_Id;
2003 Conctyp : Node_Id;
2004 Ent : Entity_Id;
2005 Ent_Acc : Entity_Id;
2006 P : Entity_Id;
2007 X : Entity_Id;
2008 Plist : List_Id;
2009 Parm1 : Node_Id;
2010 Parm2 : Node_Id;
2011 Parm3 : Node_Id;
2012 Call : Node_Id;
2013 Actual : Node_Id;
2014 Formal : Node_Id;
2015 N_Node : Node_Id;
2016 N_Var : Node_Id;
2017 Comm_Name : Entity_Id;
2019 begin
2020 -- Simple entry and entry family cases merge here
2022 Ent := Entity (Ename);
2023 Ent_Acc := Entry_Parameters_Type (Ent);
2024 Conctyp := Etype (Concval);
2026 -- If prefix is an access type, dereference to obtain the task type
2028 if Is_Access_Type (Conctyp) then
2029 Conctyp := Designated_Type (Conctyp);
2030 end if;
2032 -- Special case for protected subprogram calls
2034 if Is_Protected_Type (Conctyp)
2035 and then Is_Subprogram (Entity (Ename))
2036 then
2037 if not Is_Eliminated (Entity (Ename)) then
2038 Build_Protected_Subprogram_Call
2039 (N, Ename, Convert_Concurrent (Concval, Conctyp));
2040 Analyze (N);
2041 end if;
2043 return;
2044 end if;
2046 -- First parameter is the Task_Id value from the task value or the
2047 -- Object from the protected object value, obtained by selecting
2048 -- the _Task_Id or _Object from the result of doing an unchecked
2049 -- conversion to convert the value to the corresponding record type.
2051 Parm1 := Concurrent_Ref (Concval);
2053 -- Second parameter is the entry index, computed by the routine
2054 -- provided for this purpose. The value of this expression is
2055 -- assigned to an intermediate variable to assure that any entry
2056 -- family index expressions are evaluated before the entry
2057 -- parameters.
2059 if Abort_Allowed
2060 or else Restriction_Active (No_Entry_Queue) = False
2061 or else not Is_Protected_Type (Conctyp)
2062 or else Number_Entries (Conctyp) > 1
2063 then
2064 X := Make_Defining_Identifier (Loc, Name_uX);
2066 Xdecl :=
2067 Make_Object_Declaration (Loc,
2068 Defining_Identifier => X,
2069 Object_Definition =>
2070 New_Reference_To (RTE (RE_Task_Entry_Index), Loc),
2071 Expression => Actual_Index_Expression (
2072 Loc, Entity (Ename), Index, Concval));
2074 Decls := New_List (Xdecl);
2075 Parm2 := New_Reference_To (X, Loc);
2077 else
2078 Xdecl := Empty;
2079 Decls := New_List;
2080 Parm2 := Empty;
2081 end if;
2083 -- The third parameter is the packaged parameters. If there are
2084 -- none, then it is just the null address, since nothing is passed
2086 if No (Parms) then
2087 Parm3 := New_Reference_To (RTE (RE_Null_Address), Loc);
2088 P := Empty;
2090 -- Case of parameters present, where third argument is the address
2091 -- of a packaged record containing the required parameter values.
2093 else
2094 -- First build a list of parameter values, which are
2095 -- references to objects of the parameter types.
2097 Plist := New_List;
2099 Actual := First_Actual (N);
2100 Formal := First_Formal (Ent);
2102 while Present (Actual) loop
2104 -- If it is a by_copy_type, copy it to a new variable. The
2105 -- packaged record has a field that points to this variable.
2107 if Is_By_Copy_Type (Etype (Actual)) then
2108 N_Node :=
2109 Make_Object_Declaration (Loc,
2110 Defining_Identifier =>
2111 Make_Defining_Identifier (Loc,
2112 Chars => New_Internal_Name ('J')),
2113 Aliased_Present => True,
2114 Object_Definition =>
2115 New_Reference_To (Etype (Formal), Loc));
2117 -- We have to make an assignment statement separate for
2118 -- the case of limited type. We can not assign it unless
2119 -- the Assignment_OK flag is set first.
2121 if Ekind (Formal) /= E_Out_Parameter then
2122 N_Var :=
2123 New_Reference_To (Defining_Identifier (N_Node), Loc);
2124 Set_Assignment_OK (N_Var);
2125 Append_To (Stats,
2126 Make_Assignment_Statement (Loc,
2127 Name => N_Var,
2128 Expression => Relocate_Node (Actual)));
2129 end if;
2131 Append (N_Node, Decls);
2133 Append_To (Plist,
2134 Make_Attribute_Reference (Loc,
2135 Attribute_Name => Name_Unchecked_Access,
2136 Prefix =>
2137 New_Reference_To (Defining_Identifier (N_Node), Loc)));
2138 else
2139 Append_To (Plist,
2140 Make_Reference (Loc, Prefix => Relocate_Node (Actual)));
2141 end if;
2143 Next_Actual (Actual);
2144 Next_Formal_With_Extras (Formal);
2145 end loop;
2147 -- Now build the declaration of parameters initialized with the
2148 -- aggregate containing this constructed parameter list.
2150 P := Make_Defining_Identifier (Loc, Name_uP);
2152 Pdecl :=
2153 Make_Object_Declaration (Loc,
2154 Defining_Identifier => P,
2155 Object_Definition =>
2156 New_Reference_To (Designated_Type (Ent_Acc), Loc),
2157 Expression =>
2158 Make_Aggregate (Loc, Expressions => Plist));
2160 Parm3 :=
2161 Make_Attribute_Reference (Loc,
2162 Attribute_Name => Name_Address,
2163 Prefix => New_Reference_To (P, Loc));
2165 Append (Pdecl, Decls);
2166 end if;
2168 -- Now we can create the call, case of protected type
2170 if Is_Protected_Type (Conctyp) then
2171 if Abort_Allowed
2172 or else Restriction_Active (No_Entry_Queue) = False
2173 or else Number_Entries (Conctyp) > 1
2174 then
2175 -- Change the type of the index declaration
2177 Set_Object_Definition (Xdecl,
2178 New_Reference_To (RTE (RE_Protected_Entry_Index), Loc));
2180 -- Some additional declarations for protected entry calls
2182 if No (Decls) then
2183 Decls := New_List;
2184 end if;
2186 -- Bnn : Communications_Block;
2188 Comm_Name :=
2189 Make_Defining_Identifier (Loc, New_Internal_Name ('B'));
2191 Append_To (Decls,
2192 Make_Object_Declaration (Loc,
2193 Defining_Identifier => Comm_Name,
2194 Object_Definition =>
2195 New_Reference_To (RTE (RE_Communication_Block), Loc)));
2197 -- Some additional statements for protected entry calls
2199 -- Protected_Entry_Call (
2200 -- Object => po._object'Access,
2201 -- E => <entry index>;
2202 -- Uninterpreted_Data => P'Address;
2203 -- Mode => Simple_Call;
2204 -- Block => Bnn);
2206 Call :=
2207 Make_Procedure_Call_Statement (Loc,
2208 Name =>
2209 New_Reference_To (RTE (RE_Protected_Entry_Call), Loc),
2211 Parameter_Associations => New_List (
2212 Make_Attribute_Reference (Loc,
2213 Attribute_Name => Name_Unchecked_Access,
2214 Prefix => Parm1),
2215 Parm2,
2216 Parm3,
2217 New_Reference_To (RTE (RE_Simple_Call), Loc),
2218 New_Occurrence_Of (Comm_Name, Loc)));
2220 else
2221 -- Protected_Single_Entry_Call (
2222 -- Object => po._object'Access,
2223 -- Uninterpreted_Data => P'Address;
2224 -- Mode => Simple_Call);
2226 Call :=
2227 Make_Procedure_Call_Statement (Loc,
2228 Name => New_Reference_To (
2229 RTE (RE_Protected_Single_Entry_Call), Loc),
2231 Parameter_Associations => New_List (
2232 Make_Attribute_Reference (Loc,
2233 Attribute_Name => Name_Unchecked_Access,
2234 Prefix => Parm1),
2235 Parm3,
2236 New_Reference_To (RTE (RE_Simple_Call), Loc)));
2237 end if;
2239 -- Case of task type
2241 else
2242 Call :=
2243 Make_Procedure_Call_Statement (Loc,
2244 Name => New_Reference_To (RTE (RE_Call_Simple), Loc),
2245 Parameter_Associations => New_List (Parm1, Parm2, Parm3));
2247 end if;
2249 Append_To (Stats, Call);
2251 -- If there are out or in/out parameters by copy
2252 -- add assignment statements for the result values.
2254 if Present (Parms) then
2255 Actual := First_Actual (N);
2256 Formal := First_Formal (Ent);
2258 Set_Assignment_OK (Actual);
2259 while Present (Actual) loop
2260 if Is_By_Copy_Type (Etype (Actual))
2261 and then Ekind (Formal) /= E_In_Parameter
2262 then
2263 N_Node :=
2264 Make_Assignment_Statement (Loc,
2265 Name => New_Copy (Actual),
2266 Expression =>
2267 Make_Explicit_Dereference (Loc,
2268 Make_Selected_Component (Loc,
2269 Prefix => New_Reference_To (P, Loc),
2270 Selector_Name =>
2271 Make_Identifier (Loc, Chars (Formal)))));
2273 -- In all cases (including limited private types) we
2274 -- want the assignment to be valid.
2276 Set_Assignment_OK (Name (N_Node));
2278 -- If the call is the triggering alternative in an
2279 -- asynchronous select, or the entry_call alternative
2280 -- of a conditional entry call, the assignments for in-out
2281 -- parameters are incorporated into the statement list
2282 -- that follows, so that there are executed only if the
2283 -- entry call succeeds.
2285 if (Nkind (Parent (N)) = N_Triggering_Alternative
2286 and then N = Triggering_Statement (Parent (N)))
2287 or else
2288 (Nkind (Parent (N)) = N_Entry_Call_Alternative
2289 and then N = Entry_Call_Statement (Parent (N)))
2290 then
2291 if No (Statements (Parent (N))) then
2292 Set_Statements (Parent (N), New_List);
2293 end if;
2295 Prepend (N_Node, Statements (Parent (N)));
2297 else
2298 Insert_After (Call, N_Node);
2299 end if;
2300 end if;
2302 Next_Actual (Actual);
2303 Next_Formal_With_Extras (Formal);
2304 end loop;
2305 end if;
2307 -- Finally, create block and analyze it
2309 Rewrite (N,
2310 Make_Block_Statement (Loc,
2311 Declarations => Decls,
2312 Handled_Statement_Sequence =>
2313 Make_Handled_Sequence_Of_Statements (Loc,
2314 Statements => Stats)));
2316 Analyze (N);
2317 end;
2318 end Build_Simple_Entry_Call;
2320 --------------------------------
2321 -- Build_Task_Activation_Call --
2322 --------------------------------
2324 procedure Build_Task_Activation_Call (N : Node_Id) is
2325 Loc : constant Source_Ptr := Sloc (N);
2326 Chain : Entity_Id;
2327 Call : Node_Id;
2328 Name : Node_Id;
2329 P : Node_Id;
2331 begin
2332 -- Get the activation chain entity. Except in the case of a package
2333 -- body, this is in the node that w as passed. For a package body, we
2334 -- have to find the corresponding package declaration node.
2336 if Nkind (N) = N_Package_Body then
2337 P := Corresponding_Spec (N);
2339 loop
2340 P := Parent (P);
2341 exit when Nkind (P) = N_Package_Declaration;
2342 end loop;
2344 Chain := Activation_Chain_Entity (P);
2346 else
2347 Chain := Activation_Chain_Entity (N);
2348 end if;
2350 if Present (Chain) then
2351 if Restricted_Profile then
2352 Name := New_Reference_To (RTE (RE_Activate_Restricted_Tasks), Loc);
2353 else
2354 Name := New_Reference_To (RTE (RE_Activate_Tasks), Loc);
2355 end if;
2357 Call :=
2358 Make_Procedure_Call_Statement (Loc,
2359 Name => Name,
2360 Parameter_Associations =>
2361 New_List (Make_Attribute_Reference (Loc,
2362 Prefix => New_Occurrence_Of (Chain, Loc),
2363 Attribute_Name => Name_Unchecked_Access)));
2365 if Nkind (N) = N_Package_Declaration then
2366 if Present (Corresponding_Body (N)) then
2367 null;
2369 elsif Present (Private_Declarations (Specification (N))) then
2370 Append (Call, Private_Declarations (Specification (N)));
2372 else
2373 Append (Call, Visible_Declarations (Specification (N)));
2374 end if;
2376 else
2377 if Present (Handled_Statement_Sequence (N)) then
2379 -- The call goes at the start of the statement sequence, but
2380 -- after the start of exception range label if one is present.
2382 declare
2383 Stm : Node_Id;
2385 begin
2386 Stm := First (Statements (Handled_Statement_Sequence (N)));
2388 if Nkind (Stm) = N_Label and then Exception_Junk (Stm) then
2389 Next (Stm);
2390 end if;
2392 Insert_Before (Stm, Call);
2393 end;
2395 else
2396 Set_Handled_Statement_Sequence (N,
2397 Make_Handled_Sequence_Of_Statements (Loc,
2398 Statements => New_List (Call)));
2399 end if;
2400 end if;
2402 Analyze (Call);
2403 Check_Task_Activation (N);
2404 end if;
2405 end Build_Task_Activation_Call;
2407 -------------------------------
2408 -- Build_Task_Allocate_Block --
2409 -------------------------------
2411 procedure Build_Task_Allocate_Block
2412 (Actions : List_Id;
2413 N : Node_Id;
2414 Args : List_Id)
2416 T : constant Entity_Id := Entity (Expression (N));
2417 Init : constant Entity_Id := Base_Init_Proc (T);
2418 Loc : constant Source_Ptr := Sloc (N);
2419 Chain : constant Entity_Id :=
2420 Make_Defining_Identifier (Loc, Name_uChain);
2422 Blkent : Entity_Id;
2423 Block : Node_Id;
2425 begin
2426 Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
2428 Block :=
2429 Make_Block_Statement (Loc,
2430 Identifier => New_Reference_To (Blkent, Loc),
2431 Declarations => New_List (
2433 -- _Chain : Activation_Chain;
2435 Make_Object_Declaration (Loc,
2436 Defining_Identifier => Chain,
2437 Aliased_Present => True,
2438 Object_Definition =>
2439 New_Reference_To (RTE (RE_Activation_Chain), Loc))),
2441 Handled_Statement_Sequence =>
2442 Make_Handled_Sequence_Of_Statements (Loc,
2444 Statements => New_List (
2446 -- Init (Args);
2448 Make_Procedure_Call_Statement (Loc,
2449 Name => New_Reference_To (Init, Loc),
2450 Parameter_Associations => Args),
2452 -- Activate_Tasks (_Chain);
2454 Make_Procedure_Call_Statement (Loc,
2455 Name => New_Reference_To (RTE (RE_Activate_Tasks), Loc),
2456 Parameter_Associations => New_List (
2457 Make_Attribute_Reference (Loc,
2458 Prefix => New_Reference_To (Chain, Loc),
2459 Attribute_Name => Name_Unchecked_Access))))),
2461 Has_Created_Identifier => True,
2462 Is_Task_Allocation_Block => True);
2464 Append_To (Actions,
2465 Make_Implicit_Label_Declaration (Loc,
2466 Defining_Identifier => Blkent,
2467 Label_Construct => Block));
2469 Append_To (Actions, Block);
2471 Set_Activation_Chain_Entity (Block, Chain);
2472 end Build_Task_Allocate_Block;
2474 -----------------------------------------------
2475 -- Build_Task_Allocate_Block_With_Init_Stmts --
2476 -----------------------------------------------
2478 procedure Build_Task_Allocate_Block_With_Init_Stmts
2479 (Actions : List_Id;
2480 N : Node_Id;
2481 Init_Stmts : List_Id)
2483 Loc : constant Source_Ptr := Sloc (N);
2484 Chain : constant Entity_Id :=
2485 Make_Defining_Identifier (Loc, Name_uChain);
2486 Blkent : Entity_Id;
2487 Block : Node_Id;
2489 begin
2490 Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
2492 Append_To (Init_Stmts,
2493 Make_Procedure_Call_Statement (Loc,
2494 Name => New_Reference_To (RTE (RE_Activate_Tasks), Loc),
2495 Parameter_Associations => New_List (
2496 Make_Attribute_Reference (Loc,
2497 Prefix => New_Reference_To (Chain, Loc),
2498 Attribute_Name => Name_Unchecked_Access))));
2500 Block :=
2501 Make_Block_Statement (Loc,
2502 Identifier => New_Reference_To (Blkent, Loc),
2503 Declarations => New_List (
2505 -- _Chain : Activation_Chain;
2507 Make_Object_Declaration (Loc,
2508 Defining_Identifier => Chain,
2509 Aliased_Present => True,
2510 Object_Definition =>
2511 New_Reference_To (RTE (RE_Activation_Chain), Loc))),
2513 Handled_Statement_Sequence =>
2514 Make_Handled_Sequence_Of_Statements (Loc, Init_Stmts),
2516 Has_Created_Identifier => True,
2517 Is_Task_Allocation_Block => True);
2519 Append_To (Actions,
2520 Make_Implicit_Label_Declaration (Loc,
2521 Defining_Identifier => Blkent,
2522 Label_Construct => Block));
2524 Append_To (Actions, Block);
2526 Set_Activation_Chain_Entity (Block, Chain);
2527 end Build_Task_Allocate_Block_With_Init_Stmts;
2529 -----------------------------------
2530 -- Build_Task_Proc_Specification --
2531 -----------------------------------
2533 function Build_Task_Proc_Specification (T : Entity_Id) return Node_Id is
2534 Loc : constant Source_Ptr := Sloc (T);
2535 Nam : constant Name_Id := Chars (T);
2536 Ent : Entity_Id;
2538 begin
2539 Ent :=
2540 Make_Defining_Identifier (Loc,
2541 Chars => New_External_Name (Nam, 'B'));
2542 Set_Is_Internal (Ent);
2544 -- Associate the procedure with the task, if this is the declaration
2545 -- (and not the body) of the procedure.
2547 if No (Task_Body_Procedure (T)) then
2548 Set_Task_Body_Procedure (T, Ent);
2549 end if;
2551 return
2552 Make_Procedure_Specification (Loc,
2553 Defining_Unit_Name => Ent,
2554 Parameter_Specifications =>
2555 New_List (
2556 Make_Parameter_Specification (Loc,
2557 Defining_Identifier =>
2558 Make_Defining_Identifier (Loc, Name_uTask),
2559 Parameter_Type =>
2560 Make_Access_Definition (Loc,
2561 Subtype_Mark =>
2562 New_Reference_To
2563 (Corresponding_Record_Type (T), Loc)))));
2564 end Build_Task_Proc_Specification;
2566 ---------------------------------------
2567 -- Build_Unprotected_Subprogram_Body --
2568 ---------------------------------------
2570 function Build_Unprotected_Subprogram_Body
2571 (N : Node_Id;
2572 Pid : Node_Id) return Node_Id
2574 Loc : constant Source_Ptr := Sloc (N);
2575 N_Op_Spec : Node_Id;
2576 Op_Decls : List_Id;
2578 begin
2579 -- Make an unprotected version of the subprogram for use
2580 -- within the same object, with a new name and an additional
2581 -- parameter representing the object.
2583 Op_Decls := Declarations (N);
2584 N_Op_Spec :=
2585 Build_Protected_Sub_Specification
2586 (N, Pid, Unprotected => True);
2588 return
2589 Make_Subprogram_Body (Loc,
2590 Specification => N_Op_Spec,
2591 Declarations => Op_Decls,
2592 Handled_Statement_Sequence =>
2593 Handled_Statement_Sequence (N));
2594 end Build_Unprotected_Subprogram_Body;
2596 ----------------------------
2597 -- Collect_Entry_Families --
2598 ----------------------------
2600 procedure Collect_Entry_Families
2601 (Loc : Source_Ptr;
2602 Cdecls : List_Id;
2603 Current_Node : in out Node_Id;
2604 Conctyp : Entity_Id)
2606 Efam : Entity_Id;
2607 Efam_Decl : Node_Id;
2608 Efam_Type : Entity_Id;
2610 begin
2611 Efam := First_Entity (Conctyp);
2613 while Present (Efam) loop
2615 if Ekind (Efam) = E_Entry_Family then
2616 Efam_Type :=
2617 Make_Defining_Identifier (Loc,
2618 Chars => New_Internal_Name ('F'));
2620 Efam_Decl :=
2621 Make_Full_Type_Declaration (Loc,
2622 Defining_Identifier => Efam_Type,
2623 Type_Definition =>
2624 Make_Unconstrained_Array_Definition (Loc,
2625 Subtype_Marks => (New_List (
2626 New_Occurrence_Of (
2627 Base_Type
2628 (Etype (Discrete_Subtype_Definition
2629 (Parent (Efam)))), Loc))),
2631 Component_Definition =>
2632 Make_Component_Definition (Loc,
2633 Aliased_Present => False,
2634 Subtype_Indication =>
2635 New_Reference_To (Standard_Character, Loc))));
2637 Insert_After (Current_Node, Efam_Decl);
2638 Current_Node := Efam_Decl;
2639 Analyze (Efam_Decl);
2641 Append_To (Cdecls,
2642 Make_Component_Declaration (Loc,
2643 Defining_Identifier =>
2644 Make_Defining_Identifier (Loc, Chars (Efam)),
2646 Component_Definition =>
2647 Make_Component_Definition (Loc,
2648 Aliased_Present => False,
2649 Subtype_Indication =>
2650 Make_Subtype_Indication (Loc,
2651 Subtype_Mark =>
2652 New_Occurrence_Of (Efam_Type, Loc),
2654 Constraint =>
2655 Make_Index_Or_Discriminant_Constraint (Loc,
2656 Constraints => New_List (
2657 New_Occurrence_Of
2658 (Etype (Discrete_Subtype_Definition
2659 (Parent (Efam))), Loc)))))));
2661 end if;
2663 Next_Entity (Efam);
2664 end loop;
2665 end Collect_Entry_Families;
2667 --------------------
2668 -- Concurrent_Ref --
2669 --------------------
2671 -- The expression returned for a reference to a concurrent
2672 -- object has the form:
2674 -- taskV!(name)._Task_Id
2676 -- for a task, and
2678 -- objectV!(name)._Object
2680 -- for a protected object. For the case of an access to a concurrent
2681 -- object, there is an extra explicit dereference:
2683 -- taskV!(name.all)._Task_Id
2684 -- objectV!(name.all)._Object
2686 -- here taskV and objectV are the types for the associated records, which
2687 -- contain the required _Task_Id and _Object fields for tasks and
2688 -- protected objects, respectively.
2690 -- For the case of a task type name, the expression is
2692 -- Self;
2694 -- i.e. a call to the Self function which returns precisely this Task_Id
2696 -- For the case of a protected type name, the expression is
2698 -- objectR
2700 -- which is a renaming of the _object field of the current object
2701 -- object record, passed into protected operations as a parameter.
2703 function Concurrent_Ref (N : Node_Id) return Node_Id is
2704 Loc : constant Source_Ptr := Sloc (N);
2705 Ntyp : constant Entity_Id := Etype (N);
2706 Dtyp : Entity_Id;
2707 Sel : Name_Id;
2709 function Is_Current_Task (T : Entity_Id) return Boolean;
2710 -- Check whether the reference is to the immediately enclosing task
2711 -- type, or to an outer one (rare but legal).
2713 ---------------------
2714 -- Is_Current_Task --
2715 ---------------------
2717 function Is_Current_Task (T : Entity_Id) return Boolean is
2718 Scop : Entity_Id;
2720 begin
2721 Scop := Current_Scope;
2722 while Present (Scop)
2723 and then Scop /= Standard_Standard
2724 loop
2726 if Scop = T then
2727 return True;
2729 elsif Is_Task_Type (Scop) then
2730 return False;
2732 -- If this is a procedure nested within the task type, we must
2733 -- assume that it can be called from an inner task, and therefore
2734 -- cannot treat it as a local reference.
2736 elsif Is_Overloadable (Scop)
2737 and then In_Open_Scopes (T)
2738 then
2739 return False;
2741 else
2742 Scop := Scope (Scop);
2743 end if;
2744 end loop;
2746 -- We know that we are within the task body, so should have
2747 -- found it in scope.
2749 raise Program_Error;
2750 end Is_Current_Task;
2752 -- Start of processing for Concurrent_Ref
2754 begin
2755 if Is_Access_Type (Ntyp) then
2756 Dtyp := Designated_Type (Ntyp);
2758 if Is_Protected_Type (Dtyp) then
2759 Sel := Name_uObject;
2760 else
2761 Sel := Name_uTask_Id;
2762 end if;
2764 return
2765 Make_Selected_Component (Loc,
2766 Prefix =>
2767 Unchecked_Convert_To (Corresponding_Record_Type (Dtyp),
2768 Make_Explicit_Dereference (Loc, N)),
2769 Selector_Name => Make_Identifier (Loc, Sel));
2771 elsif Is_Entity_Name (N)
2772 and then Is_Concurrent_Type (Entity (N))
2773 then
2774 if Is_Task_Type (Entity (N)) then
2776 if Is_Current_Task (Entity (N)) then
2777 return
2778 Make_Function_Call (Loc,
2779 Name => New_Reference_To (RTE (RE_Self), Loc));
2781 else
2782 declare
2783 Decl : Node_Id;
2784 T_Self : constant Entity_Id
2785 := Make_Defining_Identifier (Loc, New_Internal_Name ('T'));
2786 T_Body : constant Node_Id
2787 := Parent (Corresponding_Body (Parent (Entity (N))));
2789 begin
2790 Decl := Make_Object_Declaration (Loc,
2791 Defining_Identifier => T_Self,
2792 Object_Definition =>
2793 New_Occurrence_Of (RTE (RO_ST_Task_Id), Loc),
2794 Expression =>
2795 Make_Function_Call (Loc,
2796 Name => New_Reference_To (RTE (RE_Self), Loc)));
2797 Prepend (Decl, Declarations (T_Body));
2798 Analyze (Decl);
2799 Set_Scope (T_Self, Entity (N));
2800 return New_Occurrence_Of (T_Self, Loc);
2801 end;
2802 end if;
2804 else
2805 pragma Assert (Is_Protected_Type (Entity (N)));
2806 return
2807 New_Reference_To (
2808 Object_Ref (Corresponding_Body (Parent (Base_Type (Ntyp)))),
2809 Loc);
2810 end if;
2812 else
2813 pragma Assert (Is_Concurrent_Type (Ntyp));
2815 if Is_Protected_Type (Ntyp) then
2816 Sel := Name_uObject;
2817 else
2818 Sel := Name_uTask_Id;
2819 end if;
2821 return
2822 Make_Selected_Component (Loc,
2823 Prefix =>
2824 Unchecked_Convert_To (Corresponding_Record_Type (Ntyp),
2825 New_Copy_Tree (N)),
2826 Selector_Name => Make_Identifier (Loc, Sel));
2827 end if;
2828 end Concurrent_Ref;
2830 ------------------------
2831 -- Convert_Concurrent --
2832 ------------------------
2834 function Convert_Concurrent
2835 (N : Node_Id;
2836 Typ : Entity_Id) return Node_Id
2838 begin
2839 if not Is_Concurrent_Type (Typ) then
2840 return N;
2841 else
2842 return
2843 Unchecked_Convert_To (Corresponding_Record_Type (Typ),
2844 New_Copy_Tree (N));
2845 end if;
2846 end Convert_Concurrent;
2848 ----------------------------
2849 -- Entry_Index_Expression --
2850 ----------------------------
2852 function Entry_Index_Expression
2853 (Sloc : Source_Ptr;
2854 Ent : Entity_Id;
2855 Index : Node_Id;
2856 Ttyp : Entity_Id) return Node_Id
2858 Expr : Node_Id;
2859 Num : Node_Id;
2860 Lo : Node_Id;
2861 Hi : Node_Id;
2862 Prev : Entity_Id;
2863 S : Node_Id;
2865 begin
2866 -- The queues of entries and entry families appear in textual
2867 -- order in the associated record. The entry index is computed as
2868 -- the sum of the number of queues for all entries that precede the
2869 -- designated one, to which is added the index expression, if this
2870 -- expression denotes a member of a family.
2872 -- The following is a place holder for the count of simple entries
2874 Num := Make_Integer_Literal (Sloc, 1);
2876 -- We construct an expression which is a series of addition
2877 -- operations. The first operand is the number of single entries that
2878 -- precede this one, the second operand is the index value relative
2879 -- to the start of the referenced family, and the remaining operands
2880 -- are the lengths of the entry families that precede this entry, i.e.
2881 -- the constructed expression is:
2883 -- number_simple_entries +
2884 -- (s'pos (index-value) - s'pos (family'first)) + 1 +
2885 -- family'length + ...
2887 -- where index-value is the given index value, and s is the index
2888 -- subtype (we have to use pos because the subtype might be an
2889 -- enumeration type preventing direct subtraction).
2890 -- Note that the task entry array is one-indexed.
2892 -- The upper bound of the entry family may be a discriminant, so we
2893 -- retrieve the lower bound explicitly to compute offset, rather than
2894 -- using the index subtype which may mention a discriminant.
2896 if Present (Index) then
2897 S := Etype (Discrete_Subtype_Definition (Declaration_Node (Ent)));
2899 Expr :=
2900 Make_Op_Add (Sloc,
2901 Left_Opnd => Num,
2903 Right_Opnd =>
2904 Family_Offset (
2905 Sloc,
2906 Make_Attribute_Reference (Sloc,
2907 Attribute_Name => Name_Pos,
2908 Prefix => New_Reference_To (Base_Type (S), Sloc),
2909 Expressions => New_List (Relocate_Node (Index))),
2910 Type_Low_Bound (S),
2911 Ttyp));
2912 else
2913 Expr := Num;
2914 end if;
2916 -- Now add lengths of preceding entries and entry families
2918 Prev := First_Entity (Ttyp);
2920 while Chars (Prev) /= Chars (Ent)
2921 or else (Ekind (Prev) /= Ekind (Ent))
2922 or else not Sem_Ch6.Type_Conformant (Ent, Prev)
2923 loop
2924 if Ekind (Prev) = E_Entry then
2925 Set_Intval (Num, Intval (Num) + 1);
2927 elsif Ekind (Prev) = E_Entry_Family then
2928 S :=
2929 Etype (Discrete_Subtype_Definition (Declaration_Node (Prev)));
2930 Lo := Type_Low_Bound (S);
2931 Hi := Type_High_Bound (S);
2933 Expr :=
2934 Make_Op_Add (Sloc,
2935 Left_Opnd => Expr,
2936 Right_Opnd => Family_Size (Sloc, Hi, Lo, Ttyp));
2938 -- Other components are anonymous types to be ignored
2940 else
2941 null;
2942 end if;
2944 Next_Entity (Prev);
2945 end loop;
2947 return Expr;
2948 end Entry_Index_Expression;
2950 ---------------------------
2951 -- Establish_Task_Master --
2952 ---------------------------
2954 procedure Establish_Task_Master (N : Node_Id) is
2955 Call : Node_Id;
2957 begin
2958 if Restriction_Active (No_Task_Hierarchy) = False then
2959 Call := Build_Runtime_Call (Sloc (N), RE_Enter_Master);
2960 Prepend_To (Declarations (N), Call);
2961 Analyze (Call);
2962 end if;
2963 end Establish_Task_Master;
2965 --------------------------------
2966 -- Expand_Accept_Declarations --
2967 --------------------------------
2969 -- Part of the expansion of an accept statement involves the creation of
2970 -- a declaration that can be referenced from the statement sequence of
2971 -- the accept:
2973 -- Ann : Address;
2975 -- This declaration is inserted immediately before the accept statement
2976 -- and it is important that it be inserted before the statements of the
2977 -- statement sequence are analyzed. Thus it would be too late to create
2978 -- this declaration in the Expand_N_Accept_Statement routine, which is
2979 -- why there is a separate procedure to be called directly from Sem_Ch9.
2981 -- Ann is used to hold the address of the record containing the parameters
2982 -- (see Expand_N_Entry_Call for more details on how this record is built).
2983 -- References to the parameters do an unchecked conversion of this address
2984 -- to a pointer to the required record type, and then access the field that
2985 -- holds the value of the required parameter. The entity for the address
2986 -- variable is held as the top stack element (i.e. the last element) of the
2987 -- Accept_Address stack in the corresponding entry entity, and this element
2988 -- must be set in place before the statements are processed.
2990 -- The above description applies to the case of a stand alone accept
2991 -- statement, i.e. one not appearing as part of a select alternative.
2993 -- For the case of an accept that appears as part of a select alternative
2994 -- of a selective accept, we must still create the declaration right away,
2995 -- since Ann is needed immediately, but there is an important difference:
2997 -- The declaration is inserted before the selective accept, not before
2998 -- the accept statement (which is not part of a list anyway, and so would
2999 -- not accommodate inserted declarations)
3001 -- We only need one address variable for the entire selective accept. So
3002 -- the Ann declaration is created only for the first accept alternative,
3003 -- and subsequent accept alternatives reference the same Ann variable.
3005 -- We can distinguish the two cases by seeing whether the accept statement
3006 -- is part of a list. If not, then it must be in an accept alternative.
3008 -- To expand the requeue statement, a label is provided at the end of
3009 -- the accept statement or alternative of which it is a part, so that
3010 -- the statement can be skipped after the requeue is complete.
3011 -- This label is created here rather than during the expansion of the
3012 -- accept statement, because it will be needed by any requeue
3013 -- statements within the accept, which are expanded before the
3014 -- accept.
3016 procedure Expand_Accept_Declarations (N : Node_Id; Ent : Entity_Id) is
3017 Loc : constant Source_Ptr := Sloc (N);
3018 Ann : Entity_Id := Empty;
3019 Adecl : Node_Id;
3020 Lab_Id : Node_Id;
3021 Lab : Node_Id;
3022 Ldecl : Node_Id;
3023 Ldecl2 : Node_Id;
3025 begin
3026 if Expander_Active then
3028 -- If we have no handled statement sequence, then build a dummy
3029 -- sequence consisting of a null statement. This is only done if
3030 -- pragma FIFO_Within_Priorities is specified. The issue here is
3031 -- that even a null accept body has an effect on the called task
3032 -- in terms of its position in the queue, so we cannot optimize
3033 -- the context switch away. However, if FIFO_Within_Priorities
3034 -- is not active, the optimization is legitimate, since we can
3035 -- say that our dispatching policy (i.e. the default dispatching
3036 -- policy) reorders the queue to be the same as just before the
3037 -- call. In the absence of a specified dispatching policy, we are
3038 -- allowed to modify queue orders for a given priority at will!
3040 if Opt.Task_Dispatching_Policy = 'F' and then
3041 not Present (Handled_Statement_Sequence (N))
3042 then
3043 Set_Handled_Statement_Sequence (N,
3044 Make_Handled_Sequence_Of_Statements (Loc,
3045 New_List (Make_Null_Statement (Loc))));
3046 end if;
3048 -- Create and declare two labels to be placed at the end of the
3049 -- accept statement. The first label is used to allow requeues to
3050 -- skip the remainder of entry processing. The second label is
3051 -- used to skip the remainder of entry processing if the rendezvous
3052 -- completes in the middle of the accept body.
3054 if Present (Handled_Statement_Sequence (N)) then
3055 Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L'));
3056 Set_Entity (Lab_Id,
3057 Make_Defining_Identifier (Loc, Chars (Lab_Id)));
3058 Lab := Make_Label (Loc, Lab_Id);
3059 Ldecl :=
3060 Make_Implicit_Label_Declaration (Loc,
3061 Defining_Identifier => Entity (Lab_Id),
3062 Label_Construct => Lab);
3063 Append (Lab, Statements (Handled_Statement_Sequence (N)));
3065 Lab_Id := Make_Identifier (Loc, New_Internal_Name ('L'));
3066 Set_Entity (Lab_Id,
3067 Make_Defining_Identifier (Loc, Chars (Lab_Id)));
3068 Lab := Make_Label (Loc, Lab_Id);
3069 Ldecl2 :=
3070 Make_Implicit_Label_Declaration (Loc,
3071 Defining_Identifier => Entity (Lab_Id),
3072 Label_Construct => Lab);
3073 Append (Lab, Statements (Handled_Statement_Sequence (N)));
3075 else
3076 Ldecl := Empty;
3077 Ldecl2 := Empty;
3078 end if;
3080 -- Case of stand alone accept statement
3082 if Is_List_Member (N) then
3084 if Present (Handled_Statement_Sequence (N)) then
3085 Ann :=
3086 Make_Defining_Identifier (Loc,
3087 Chars => New_Internal_Name ('A'));
3089 Adecl :=
3090 Make_Object_Declaration (Loc,
3091 Defining_Identifier => Ann,
3092 Object_Definition =>
3093 New_Reference_To (RTE (RE_Address), Loc));
3095 Insert_Before (N, Adecl);
3096 Analyze (Adecl);
3098 Insert_Before (N, Ldecl);
3099 Analyze (Ldecl);
3101 Insert_Before (N, Ldecl2);
3102 Analyze (Ldecl2);
3103 end if;
3105 -- Case of accept statement which is in an accept alternative
3107 else
3108 declare
3109 Acc_Alt : constant Node_Id := Parent (N);
3110 Sel_Acc : constant Node_Id := Parent (Acc_Alt);
3111 Alt : Node_Id;
3113 begin
3114 pragma Assert (Nkind (Acc_Alt) = N_Accept_Alternative);
3115 pragma Assert (Nkind (Sel_Acc) = N_Selective_Accept);
3117 -- ??? Consider a single label for select statements
3119 if Present (Handled_Statement_Sequence (N)) then
3120 Prepend (Ldecl2,
3121 Statements (Handled_Statement_Sequence (N)));
3122 Analyze (Ldecl2);
3124 Prepend (Ldecl,
3125 Statements (Handled_Statement_Sequence (N)));
3126 Analyze (Ldecl);
3127 end if;
3129 -- Find first accept alternative of the selective accept. A
3130 -- valid selective accept must have at least one accept in it.
3132 Alt := First (Select_Alternatives (Sel_Acc));
3134 while Nkind (Alt) /= N_Accept_Alternative loop
3135 Next (Alt);
3136 end loop;
3138 -- If we are the first accept statement, then we have to
3139 -- create the Ann variable, as for the stand alone case,
3140 -- except that it is inserted before the selective accept.
3141 -- Similarly, a label for requeue expansion must be
3142 -- declared.
3144 if N = Accept_Statement (Alt) then
3145 Ann :=
3146 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
3148 Adecl :=
3149 Make_Object_Declaration (Loc,
3150 Defining_Identifier => Ann,
3151 Object_Definition =>
3152 New_Reference_To (RTE (RE_Address), Loc));
3154 Insert_Before (Sel_Acc, Adecl);
3155 Analyze (Adecl);
3157 -- If we are not the first accept statement, then find the
3158 -- Ann variable allocated by the first accept and use it.
3160 else
3161 Ann :=
3162 Node (Last_Elmt (Accept_Address
3163 (Entity (Entry_Direct_Name (Accept_Statement (Alt))))));
3164 end if;
3165 end;
3166 end if;
3168 -- Merge here with Ann either created or referenced, and Adecl
3169 -- pointing to the corresponding declaration. Remaining processing
3170 -- is the same for the two cases.
3172 if Present (Ann) then
3173 Append_Elmt (Ann, Accept_Address (Ent));
3174 Set_Needs_Debug_Info (Ann);
3175 end if;
3177 -- Create renaming declarations for the entry formals. Each
3178 -- reference to a formal becomes a dereference of a component
3179 -- of the parameter block, whose address is held in Ann.
3180 -- These declarations are eventually inserted into the accept
3181 -- block, and analyzed there so that they have the proper scope
3182 -- for gdb and do not conflict with other declarations.
3184 if Present (Parameter_Specifications (N))
3185 and then Present (Handled_Statement_Sequence (N))
3186 then
3187 declare
3188 Formal : Entity_Id;
3189 New_F : Entity_Id;
3190 Comp : Entity_Id;
3191 Decl : Node_Id;
3193 begin
3194 New_Scope (Ent);
3195 Formal := First_Formal (Ent);
3197 while Present (Formal) loop
3198 Comp := Entry_Component (Formal);
3199 New_F :=
3200 Make_Defining_Identifier (Sloc (Formal), Chars (Formal));
3201 Set_Etype (New_F, Etype (Formal));
3202 Set_Scope (New_F, Ent);
3203 Set_Needs_Debug_Info (New_F); -- That's the whole point.
3205 if Ekind (Formal) = E_In_Parameter then
3206 Set_Ekind (New_F, E_Constant);
3207 else
3208 Set_Ekind (New_F, E_Variable);
3209 Set_Extra_Constrained (New_F, Extra_Constrained (Formal));
3210 end if;
3212 Set_Actual_Subtype (New_F, Actual_Subtype (Formal));
3214 Decl :=
3215 Make_Object_Renaming_Declaration (Loc,
3216 Defining_Identifier => New_F,
3217 Subtype_Mark => New_Reference_To (Etype (Formal), Loc),
3218 Name =>
3219 Make_Explicit_Dereference (Loc,
3220 Make_Selected_Component (Loc,
3221 Prefix =>
3222 Unchecked_Convert_To (Entry_Parameters_Type (Ent),
3223 New_Reference_To (Ann, Loc)),
3224 Selector_Name =>
3225 New_Reference_To (Comp, Loc))));
3227 if No (Declarations (N)) then
3228 Set_Declarations (N, New_List);
3229 end if;
3231 Append (Decl, Declarations (N));
3232 Set_Renamed_Object (Formal, New_F);
3233 Next_Formal (Formal);
3234 end loop;
3236 End_Scope;
3237 end;
3238 end if;
3239 end if;
3240 end Expand_Accept_Declarations;
3242 ---------------------------------------------
3243 -- Expand_Access_Protected_Subprogram_Type --
3244 ---------------------------------------------
3246 procedure Expand_Access_Protected_Subprogram_Type (N : Node_Id) is
3247 Loc : constant Source_Ptr := Sloc (N);
3248 Comps : List_Id;
3249 T : constant Entity_Id := Defining_Identifier (N);
3250 D_T : constant Entity_Id := Designated_Type (T);
3251 D_T2 : constant Entity_Id := Make_Defining_Identifier
3252 (Loc, New_Internal_Name ('D'));
3253 E_T : constant Entity_Id := Make_Defining_Identifier
3254 (Loc, New_Internal_Name ('E'));
3255 P_List : constant List_Id := Build_Protected_Spec
3256 (N, RTE (RE_Address), False, D_T);
3257 Decl1 : Node_Id;
3258 Decl2 : Node_Id;
3259 Def1 : Node_Id;
3261 begin
3262 -- Create access to protected subprogram with full signature
3264 if Nkind (Type_Definition (N)) = N_Access_Function_Definition then
3265 Def1 :=
3266 Make_Access_Function_Definition (Loc,
3267 Parameter_Specifications => P_List,
3268 Subtype_Mark => New_Copy (Subtype_Mark (Type_Definition (N))));
3270 else
3271 Def1 :=
3272 Make_Access_Procedure_Definition (Loc,
3273 Parameter_Specifications => P_List);
3274 end if;
3276 Decl1 :=
3277 Make_Full_Type_Declaration (Loc,
3278 Defining_Identifier => D_T2,
3279 Type_Definition => Def1);
3281 Analyze (Decl1);
3282 Insert_After (N, Decl1);
3284 -- Create Equivalent_Type, a record with two components for an
3285 -- access to object and an access to subprogram.
3287 Comps := New_List (
3288 Make_Component_Declaration (Loc,
3289 Defining_Identifier =>
3290 Make_Defining_Identifier (Loc, New_Internal_Name ('P')),
3291 Component_Definition =>
3292 Make_Component_Definition (Loc,
3293 Aliased_Present => False,
3294 Subtype_Indication =>
3295 New_Occurrence_Of (RTE (RE_Address), Loc))),
3297 Make_Component_Declaration (Loc,
3298 Defining_Identifier =>
3299 Make_Defining_Identifier (Loc, New_Internal_Name ('S')),
3300 Component_Definition =>
3301 Make_Component_Definition (Loc,
3302 Aliased_Present => False,
3303 Subtype_Indication => New_Occurrence_Of (D_T2, Loc))));
3305 Decl2 :=
3306 Make_Full_Type_Declaration (Loc,
3307 Defining_Identifier => E_T,
3308 Type_Definition =>
3309 Make_Record_Definition (Loc,
3310 Component_List =>
3311 Make_Component_List (Loc,
3312 Component_Items => Comps)));
3314 Analyze (Decl2);
3315 Insert_After (Decl1, Decl2);
3316 Set_Equivalent_Type (T, E_T);
3317 end Expand_Access_Protected_Subprogram_Type;
3319 --------------------------
3320 -- Expand_Entry_Barrier --
3321 --------------------------
3323 procedure Expand_Entry_Barrier (N : Node_Id; Ent : Entity_Id) is
3324 Loc : constant Source_Ptr := Sloc (N);
3325 Prot : constant Entity_Id := Scope (Ent);
3326 Spec_Decl : constant Node_Id := Parent (Prot);
3327 Cond : constant Node_Id :=
3328 Condition (Entry_Body_Formal_Part (N));
3329 Func : Node_Id;
3330 B_F : Node_Id;
3331 Body_Decl : Node_Id;
3333 begin
3334 if No_Run_Time_Mode then
3335 Error_Msg_CRT ("entry barrier", N);
3336 return;
3337 end if;
3339 -- The body of the entry barrier must be analyzed in the context of
3340 -- the protected object, but its scope is external to it, just as any
3341 -- other unprotected version of a protected operation. The specification
3342 -- has been produced when the protected type declaration was elaborated.
3343 -- We build the body, insert it in the enclosing scope, but analyze it
3344 -- in the current context. A more uniform approach would be to treat a
3345 -- barrier just as a protected function, and discard the protected
3346 -- version of it because it is never called.
3348 if Expander_Active then
3349 B_F := Build_Barrier_Function (N, Ent, Prot);
3350 Func := Barrier_Function (Ent);
3351 Set_Corresponding_Spec (B_F, Func);
3353 Body_Decl := Parent (Corresponding_Body (Spec_Decl));
3355 if Nkind (Parent (Body_Decl)) = N_Subunit then
3356 Body_Decl := Corresponding_Stub (Parent (Body_Decl));
3357 end if;
3359 Insert_Before_And_Analyze (Body_Decl, B_F);
3361 Update_Prival_Subtypes (B_F);
3363 Set_Privals (Spec_Decl, N, Loc);
3364 Set_Discriminals (Spec_Decl);
3365 Set_Scope (Func, Scope (Prot));
3367 else
3368 Analyze_And_Resolve (Cond, Any_Boolean);
3369 end if;
3371 -- The Ravenscar profile restricts barriers to simple variables
3372 -- declared within the protected object. We also allow Boolean
3373 -- constants, since these appear in several published examples
3374 -- and are also allowed by the Aonix compiler.
3376 -- Note that after analysis variables in this context will be
3377 -- replaced by the corresponding prival, that is to say a renaming
3378 -- of a selected component of the form _Object.Var. If expansion is
3379 -- disabled, as within a generic, we check that the entity appears in
3380 -- the current scope.
3382 if Is_Entity_Name (Cond) then
3384 if Entity (Cond) = Standard_False
3385 or else
3386 Entity (Cond) = Standard_True
3387 then
3388 return;
3390 elsif not Expander_Active
3391 and then Scope (Entity (Cond)) = Current_Scope
3392 then
3393 return;
3395 -- Check for case of _object.all.field (note that the explicit
3396 -- dereference gets inserted by analyze/expand of _object.field)
3398 elsif Present (Renamed_Object (Entity (Cond)))
3399 and then
3400 Nkind (Renamed_Object (Entity (Cond))) = N_Selected_Component
3401 and then
3402 Chars
3403 (Prefix
3404 (Prefix (Renamed_Object (Entity (Cond))))) = Name_uObject
3405 then
3406 return;
3407 end if;
3408 end if;
3410 -- It is not a boolean variable or literal, so check the restriction
3412 Check_Restriction (Simple_Barriers, Cond);
3413 end Expand_Entry_Barrier;
3415 ------------------------------------
3416 -- Expand_Entry_Body_Declarations --
3417 ------------------------------------
3419 procedure Expand_Entry_Body_Declarations (N : Node_Id) is
3420 Loc : constant Source_Ptr := Sloc (N);
3421 Index_Spec : Node_Id;
3423 begin
3424 if Expander_Active then
3426 -- Expand entry bodies corresponding to entry families
3427 -- by assigning a placeholder for the constant that will
3428 -- be used to expand references to the entry index parameter.
3430 Index_Spec :=
3431 Entry_Index_Specification (Entry_Body_Formal_Part (N));
3433 if Present (Index_Spec) then
3434 Set_Entry_Index_Constant (
3435 Defining_Identifier (Index_Spec),
3436 Make_Defining_Identifier (Loc, New_Internal_Name ('J')));
3437 end if;
3438 end if;
3439 end Expand_Entry_Body_Declarations;
3441 ------------------------------
3442 -- Expand_N_Abort_Statement --
3443 ------------------------------
3445 -- Expand abort T1, T2, .. Tn; into:
3446 -- Abort_Tasks (Task_List'(1 => T1.Task_Id, 2 => T2.Task_Id ...))
3448 procedure Expand_N_Abort_Statement (N : Node_Id) is
3449 Loc : constant Source_Ptr := Sloc (N);
3450 Tlist : constant List_Id := Names (N);
3451 Count : Nat;
3452 Aggr : Node_Id;
3453 Tasknm : Node_Id;
3455 begin
3456 Aggr := Make_Aggregate (Loc, Component_Associations => New_List);
3457 Count := 0;
3459 Tasknm := First (Tlist);
3461 while Present (Tasknm) loop
3462 Count := Count + 1;
3463 Append_To (Component_Associations (Aggr),
3464 Make_Component_Association (Loc,
3465 Choices => New_List (
3466 Make_Integer_Literal (Loc, Count)),
3467 Expression => Concurrent_Ref (Tasknm)));
3468 Next (Tasknm);
3469 end loop;
3471 Rewrite (N,
3472 Make_Procedure_Call_Statement (Loc,
3473 Name => New_Reference_To (RTE (RE_Abort_Tasks), Loc),
3474 Parameter_Associations => New_List (
3475 Make_Qualified_Expression (Loc,
3476 Subtype_Mark => New_Reference_To (RTE (RE_Task_List), Loc),
3477 Expression => Aggr))));
3479 Analyze (N);
3480 end Expand_N_Abort_Statement;
3482 -------------------------------
3483 -- Expand_N_Accept_Statement --
3484 -------------------------------
3486 -- This procedure handles expansion of accept statements that stand
3487 -- alone, i.e. they are not part of an accept alternative. The expansion
3488 -- of accept statement in accept alternatives is handled by the routines
3489 -- Expand_N_Accept_Alternative and Expand_N_Selective_Accept. The
3490 -- following description applies only to stand alone accept statements.
3492 -- If there is no handled statement sequence, or only null statements,
3493 -- then this is called a trivial accept, and the expansion is:
3495 -- Accept_Trivial (entry-index)
3497 -- If there is a handled statement sequence, then the expansion is:
3499 -- Ann : Address;
3500 -- {Lnn : Label}
3502 -- begin
3503 -- begin
3504 -- Accept_Call (entry-index, Ann);
3505 -- Renaming_Declarations for formals
3506 -- <statement sequence from N_Accept_Statement node>
3507 -- Complete_Rendezvous;
3508 -- <<Lnn>>
3510 -- exception
3511 -- when ... =>
3512 -- <exception handler from N_Accept_Statement node>
3513 -- Complete_Rendezvous;
3514 -- when ... =>
3515 -- <exception handler from N_Accept_Statement node>
3516 -- Complete_Rendezvous;
3517 -- ...
3518 -- end;
3520 -- exception
3521 -- when all others =>
3522 -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
3523 -- end;
3525 -- The first three declarations were already inserted ahead of the
3526 -- accept statement by the Expand_Accept_Declarations procedure, which
3527 -- was called directly from the semantics during analysis of the accept.
3528 -- statement, before analyzing its contained statements.
3530 -- The declarations from the N_Accept_Statement, as noted in Sinfo, come
3531 -- from possible expansion activity (the original source of course does
3532 -- not have any declarations associated with the accept statement, since
3533 -- an accept statement has no declarative part). In particular, if the
3534 -- expander is active, the first such declaration is the declaration of
3535 -- the Accept_Params_Ptr entity (see Sem_Ch9.Analyze_Accept_Statement).
3537 -- The two blocks are merged into a single block if the inner block has
3538 -- no exception handlers, but otherwise two blocks are required, since
3539 -- exceptions might be raised in the exception handlers of the inner
3540 -- block, and Exceptional_Complete_Rendezvous must be called.
3542 procedure Expand_N_Accept_Statement (N : Node_Id) is
3543 Loc : constant Source_Ptr := Sloc (N);
3544 Stats : constant Node_Id := Handled_Statement_Sequence (N);
3545 Ename : constant Node_Id := Entry_Direct_Name (N);
3546 Eindx : constant Node_Id := Entry_Index (N);
3547 Eent : constant Entity_Id := Entity (Ename);
3548 Acstack : constant Elist_Id := Accept_Address (Eent);
3549 Ann : constant Entity_Id := Node (Last_Elmt (Acstack));
3550 Ttyp : constant Entity_Id := Etype (Scope (Eent));
3551 Blkent : Entity_Id;
3552 Call : Node_Id;
3553 Block : Node_Id;
3555 function Null_Statements (Stats : List_Id) return Boolean;
3556 -- Check for null statement sequence (i.e a list of labels and
3557 -- null statements)
3559 function Null_Statements (Stats : List_Id) return Boolean is
3560 Stmt : Node_Id;
3562 begin
3563 Stmt := First (Stats);
3564 while Nkind (Stmt) /= N_Empty
3565 and then (Nkind (Stmt) = N_Null_Statement
3566 or else
3567 Nkind (Stmt) = N_Label)
3568 loop
3569 Next (Stmt);
3570 end loop;
3572 return Nkind (Stmt) = N_Empty;
3573 end Null_Statements;
3575 -- Start of processing for Expand_N_Accept_Statement
3577 begin
3578 -- If accept statement is not part of a list, then its parent must be
3579 -- an accept alternative, and, as described above, we do not do any
3580 -- expansion for such accept statements at this level.
3582 if not Is_List_Member (N) then
3583 pragma Assert (Nkind (Parent (N)) = N_Accept_Alternative);
3584 return;
3586 -- Trivial accept case (no statement sequence, or null statements).
3587 -- If the accept statement has declarations, then just insert them
3588 -- before the procedure call.
3590 -- We avoid this optimization when FIFO_Within_Priorities is active,
3591 -- since it is not correct according to annex D semantics. The problem
3592 -- is that the call is required to reorder the acceptors position on
3593 -- its ready queue, even though there is nothing to be done. However,
3594 -- if no policy is specified, then we decide that our dispatching
3595 -- policy always reorders the queue right after the RV to look the
3596 -- way they were just before the RV. Since we are allowed to freely
3597 -- reorder same-priority queues (this is part of what dispatching
3598 -- policies are all about), the optimization is legitimate.
3600 elsif Opt.Task_Dispatching_Policy /= 'F'
3601 and then (No (Stats) or else Null_Statements (Statements (Stats)))
3602 then
3603 -- Remove declarations for renamings, because the parameter block
3604 -- will not be assigned.
3606 declare
3607 D : Node_Id;
3608 Next_D : Node_Id;
3610 begin
3611 D := First (Declarations (N));
3613 while Present (D) loop
3614 Next_D := Next (D);
3615 if Nkind (D) = N_Object_Renaming_Declaration then
3616 Remove (D);
3617 end if;
3619 D := Next_D;
3620 end loop;
3621 end;
3623 if Present (Declarations (N)) then
3624 Insert_Actions (N, Declarations (N));
3625 end if;
3627 Rewrite (N,
3628 Make_Procedure_Call_Statement (Loc,
3629 Name => New_Reference_To (RTE (RE_Accept_Trivial), Loc),
3630 Parameter_Associations => New_List (
3631 Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp))));
3633 Analyze (N);
3635 -- Discard Entry_Address that was created for it, so it will not be
3636 -- emitted if this accept statement is in the statement part of a
3637 -- delay alternative.
3639 if Present (Stats) then
3640 Remove_Last_Elmt (Acstack);
3641 end if;
3643 -- Case of statement sequence present
3645 else
3646 -- Construct the block, using the declarations from the accept
3647 -- statement if any to initialize the declarations of the block.
3649 Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
3650 Set_Ekind (Blkent, E_Block);
3651 Set_Etype (Blkent, Standard_Void_Type);
3652 Set_Scope (Blkent, Current_Scope);
3654 Block :=
3655 Make_Block_Statement (Loc,
3656 Identifier => New_Reference_To (Blkent, Loc),
3657 Declarations => Declarations (N),
3658 Handled_Statement_Sequence => Build_Accept_Body (N));
3660 -- Prepend call to Accept_Call to main statement sequence
3661 -- If the accept has exception handlers, the statement sequence
3662 -- is wrapped in a block. Insert call and renaming declarations
3663 -- in the declarations of the block, so they are elaborated before
3664 -- the handlers.
3666 Call :=
3667 Make_Procedure_Call_Statement (Loc,
3668 Name => New_Reference_To (RTE (RE_Accept_Call), Loc),
3669 Parameter_Associations => New_List (
3670 Entry_Index_Expression (Loc, Entity (Ename), Eindx, Ttyp),
3671 New_Reference_To (Ann, Loc)));
3673 if Parent (Stats) = N then
3674 Prepend (Call, Statements (Stats));
3675 else
3676 Set_Declarations
3677 (Parent (Stats),
3678 New_List (Call));
3679 end if;
3681 Analyze (Call);
3683 New_Scope (Blkent);
3685 declare
3686 D : Node_Id;
3687 Next_D : Node_Id;
3688 Typ : Entity_Id;
3689 begin
3690 D := First (Declarations (N));
3692 while Present (D) loop
3693 Next_D := Next (D);
3695 if Nkind (D) = N_Object_Renaming_Declaration then
3696 -- The renaming declarations for the formals were
3697 -- created during analysis of the accept statement,
3698 -- and attached to the list of declarations. Place
3699 -- them now in the context of the accept block or
3700 -- subprogram.
3702 Remove (D);
3703 Typ := Entity (Subtype_Mark (D));
3704 Insert_After (Call, D);
3705 Analyze (D);
3707 -- If the formal is class_wide, it does not have an
3708 -- actual subtype. The analysis of the renaming declaration
3709 -- creates one, but we need to retain the class-wide
3710 -- nature of the entity.
3712 if Is_Class_Wide_Type (Typ) then
3713 Set_Etype (Defining_Identifier (D), Typ);
3714 end if;
3716 end if;
3718 D := Next_D;
3719 end loop;
3720 end;
3722 End_Scope;
3724 -- Replace the accept statement by the new block
3726 Rewrite (N, Block);
3727 Analyze (N);
3729 -- Last step is to unstack the Accept_Address value
3731 Remove_Last_Elmt (Acstack);
3732 end if;
3733 end Expand_N_Accept_Statement;
3735 ----------------------------------
3736 -- Expand_N_Asynchronous_Select --
3737 ----------------------------------
3739 -- This procedure assumes that the trigger statement is an entry call. A
3740 -- delay alternative should already have been expanded into an entry call
3741 -- to the appropriate delay object Wait entry.
3743 -- If the trigger is a task entry call, the select is implemented with
3744 -- a Task_Entry_Call:
3746 -- declare
3747 -- B : Boolean;
3748 -- C : Boolean;
3749 -- P : parms := (parm, parm, parm);
3751 -- -- Clean is added by Exp_Ch7.Expand_Cleanup_Actions
3753 -- procedure _clean is
3754 -- begin
3755 -- ...
3756 -- Cancel_Task_Entry_Call (C);
3757 -- ...
3758 -- end _clean;
3760 -- begin
3761 -- Abort_Defer;
3762 -- Task_Entry_Call
3763 -- (acceptor-task,
3764 -- entry-index,
3765 -- P'Address,
3766 -- Asynchronous_Call,
3767 -- B);
3769 -- begin
3770 -- begin
3771 -- Abort_Undefer;
3772 -- abortable-part
3773 -- at end
3774 -- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions.
3775 -- end;
3777 -- exception
3778 -- when Abort_Signal => Abort_Undefer;
3779 -- end;
3780 -- parm := P.param;
3781 -- parm := P.param;
3782 -- ...
3783 -- if not C then
3784 -- triggered-statements
3785 -- end if;
3786 -- end;
3788 -- Note that Build_Simple_Entry_Call is used to expand the entry
3789 -- of the asynchronous entry call (by the
3790 -- Expand_N_Entry_Call_Statement procedure) as follows:
3792 -- declare
3793 -- P : parms := (parm, parm, parm);
3794 -- begin
3795 -- Call_Simple (acceptor-task, entry-index, P'Address);
3796 -- parm := P.param;
3797 -- parm := P.param;
3798 -- ...
3799 -- end;
3801 -- so the task at hand is to convert the latter expansion into the former
3803 -- If the trigger is a protected entry call, the select is
3804 -- implemented with Protected_Entry_Call:
3806 -- declare
3807 -- P : E1_Params := (param, param, param);
3808 -- Bnn : Communications_Block;
3810 -- begin
3811 -- declare
3812 -- -- Clean is added by Exp_Ch7.Expand_Cleanup_Actions.
3813 -- procedure _clean is
3814 -- begin
3815 -- ...
3816 -- if Enqueued (Bnn) then
3817 -- Cancel_Protected_Entry_Call (Bnn);
3818 -- end if;
3819 -- ...
3820 -- end _clean;
3822 -- begin
3823 -- begin
3824 -- Protected_Entry_Call (
3825 -- Object => po._object'Access,
3826 -- E => <entry index>;
3827 -- Uninterpreted_Data => P'Address;
3828 -- Mode => Asynchronous_Call;
3829 -- Block => Bnn);
3830 -- if Enqueued (Bnn) then
3831 -- <abortable part>
3832 -- end if;
3833 -- at end
3834 -- _clean; -- Added by Exp_Ch7.Expand_Cleanup_Actions.
3835 -- end;
3837 -- exception
3838 -- when Abort_Signal =>
3839 -- Abort_Undefer;
3840 -- null;
3841 -- end;
3843 -- if not Cancelled (Bnn) then
3844 -- triggered statements
3845 -- end if;
3846 -- end;
3848 -- Build_Simple_Entry_Call is used to expand the all to a simple
3849 -- protected entry call:
3851 -- declare
3852 -- P : E1_Params := (param, param, param);
3853 -- Bnn : Communications_Block;
3855 -- begin
3856 -- Protected_Entry_Call (
3857 -- Object => po._object'Access,
3858 -- E => <entry index>;
3859 -- Uninterpreted_Data => P'Address;
3860 -- Mode => Simple_Call;
3861 -- Block => Bnn);
3862 -- parm := P.param;
3863 -- parm := P.param;
3864 -- ...
3865 -- end;
3867 -- The job is to convert this to the asynchronous form
3869 -- If the trigger is a delay statement, it will have been expanded into a
3870 -- call to one of the GNARL delay procedures. This routine will convert
3871 -- this into a protected entry call on a delay object and then continue
3872 -- processing as for a protected entry call trigger. This requires
3873 -- declaring a Delay_Block object and adding a pointer to this object to
3874 -- the parameter list of the delay procedure to form the parameter list of
3875 -- the entry call. This object is used by the runtime to queue the delay
3876 -- request.
3878 -- For a description of the use of P and the assignments after the
3879 -- call, see Expand_N_Entry_Call_Statement.
3881 procedure Expand_N_Asynchronous_Select (N : Node_Id) is
3882 Loc : constant Source_Ptr := Sloc (N);
3883 Trig : constant Node_Id := Triggering_Alternative (N);
3884 Abrt : constant Node_Id := Abortable_Part (N);
3885 Tstats : constant List_Id := Statements (Trig);
3886 Astats : constant List_Id := Statements (Abrt);
3888 Ecall : Node_Id;
3889 Concval : Node_Id;
3890 Ename : Node_Id;
3891 Index : Node_Id;
3892 Hdle : List_Id;
3893 Decls : List_Id;
3894 Decl : Node_Id;
3895 Parms : List_Id;
3896 Parm : Node_Id;
3897 Call : Node_Id;
3898 Stmts : List_Id;
3899 Enqueue_Call : Node_Id;
3900 Stmt : Node_Id;
3901 B : Entity_Id;
3902 Pdef : Entity_Id;
3903 Dblock_Ent : Entity_Id;
3904 N_Orig : Node_Id;
3905 Abortable_Block : Node_Id;
3906 Cancel_Param : Entity_Id;
3907 Blkent : Entity_Id;
3908 Target_Undefer : RE_Id;
3909 Undefer_Args : List_Id := No_List;
3911 begin
3912 Blkent := Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
3913 Ecall := Triggering_Statement (Trig);
3915 -- The arguments in the call may require dynamic allocation, and the
3916 -- call statement may have been transformed into a block. The block
3917 -- may contain additional declarations for internal entities, and the
3918 -- original call is found by sequential search.
3920 if Nkind (Ecall) = N_Block_Statement then
3921 Ecall := First (Statements (Handled_Statement_Sequence (Ecall)));
3923 while Nkind (Ecall) /= N_Procedure_Call_Statement
3924 and then Nkind (Ecall) /= N_Entry_Call_Statement
3925 loop
3926 Next (Ecall);
3927 end loop;
3928 end if;
3930 -- If a delay was used as a trigger, it will have been expanded
3931 -- into a procedure call. Convert it to the appropriate sequence of
3932 -- statements, similar to what is done for a task entry call.
3933 -- Note that this currently supports only Duration, Real_Time.Time,
3934 -- and Calendar.Time.
3936 if Nkind (Ecall) = N_Procedure_Call_Statement then
3938 -- Add a Delay_Block object to the parameter list of the
3939 -- delay procedure to form the parameter list of the Wait
3940 -- entry call.
3942 Dblock_Ent := Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
3944 Pdef := Entity (Name (Ecall));
3946 if Is_RTE (Pdef, RO_CA_Delay_For) then
3947 Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_Duration), Loc);
3949 elsif Is_RTE (Pdef, RO_CA_Delay_Until) then
3950 Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_Calendar), Loc);
3952 else pragma Assert (Is_RTE (Pdef, RO_RT_Delay_Until));
3953 Enqueue_Call := New_Reference_To (RTE (RE_Enqueue_RT), Loc);
3954 end if;
3956 Append_To (Parameter_Associations (Ecall),
3957 Make_Attribute_Reference (Loc,
3958 Prefix => New_Reference_To (Dblock_Ent, Loc),
3959 Attribute_Name => Name_Unchecked_Access));
3961 -- Create the inner block to protect the abortable part
3963 Hdle := New_List (
3964 Make_Exception_Handler (Loc,
3965 Exception_Choices =>
3966 New_List (New_Reference_To (Stand.Abort_Signal, Loc)),
3967 Statements => New_List (
3968 Make_Procedure_Call_Statement (Loc,
3969 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)))));
3971 Prepend_To (Astats,
3972 Make_Procedure_Call_Statement (Loc,
3973 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)));
3975 Abortable_Block :=
3976 Make_Block_Statement (Loc,
3977 Identifier => New_Reference_To (Blkent, Loc),
3978 Handled_Statement_Sequence =>
3979 Make_Handled_Sequence_Of_Statements (Loc,
3980 Statements => Astats),
3981 Has_Created_Identifier => True,
3982 Is_Asynchronous_Call_Block => True);
3984 -- Append call to if Enqueue (When, DB'Unchecked_Access) then
3986 Rewrite (Ecall,
3987 Make_Implicit_If_Statement (N,
3988 Condition => Make_Function_Call (Loc,
3989 Name => Enqueue_Call,
3990 Parameter_Associations => Parameter_Associations (Ecall)),
3991 Then_Statements =>
3992 New_List (Make_Block_Statement (Loc,
3993 Handled_Statement_Sequence =>
3994 Make_Handled_Sequence_Of_Statements (Loc,
3995 Statements => New_List (
3996 Make_Implicit_Label_Declaration (Loc,
3997 Defining_Identifier => Blkent,
3998 Label_Construct => Abortable_Block),
3999 Abortable_Block),
4000 Exception_Handlers => Hdle)))));
4002 Stmts := New_List (Ecall);
4004 -- Construct statement sequence for new block
4006 Append_To (Stmts,
4007 Make_Implicit_If_Statement (N,
4008 Condition => Make_Function_Call (Loc,
4009 Name => New_Reference_To (
4010 RTE (RE_Timed_Out), Loc),
4011 Parameter_Associations => New_List (
4012 Make_Attribute_Reference (Loc,
4013 Prefix => New_Reference_To (Dblock_Ent, Loc),
4014 Attribute_Name => Name_Unchecked_Access))),
4015 Then_Statements => Tstats));
4017 -- The result is the new block
4019 Set_Entry_Cancel_Parameter (Blkent, Dblock_Ent);
4021 Rewrite (N,
4022 Make_Block_Statement (Loc,
4023 Declarations => New_List (
4024 Make_Object_Declaration (Loc,
4025 Defining_Identifier => Dblock_Ent,
4026 Aliased_Present => True,
4027 Object_Definition => New_Reference_To (
4028 RTE (RE_Delay_Block), Loc))),
4030 Handled_Statement_Sequence =>
4031 Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
4033 Analyze (N);
4034 return;
4036 else
4037 N_Orig := N;
4038 end if;
4040 Extract_Entry (Ecall, Concval, Ename, Index);
4041 Build_Simple_Entry_Call (Ecall, Concval, Ename, Index);
4043 Stmts := Statements (Handled_Statement_Sequence (Ecall));
4044 Decls := Declarations (Ecall);
4046 if Is_Protected_Type (Etype (Concval)) then
4048 -- Get the declarations of the block expanded from the entry call
4050 Decl := First (Decls);
4051 while Present (Decl)
4052 and then (Nkind (Decl) /= N_Object_Declaration
4053 or else not Is_RTE
4054 (Etype (Object_Definition (Decl)), RE_Communication_Block))
4055 loop
4056 Next (Decl);
4057 end loop;
4059 pragma Assert (Present (Decl));
4060 Cancel_Param := Defining_Identifier (Decl);
4062 -- Change the mode of the Protected_Entry_Call call.
4063 -- Protected_Entry_Call (
4064 -- Object => po._object'Access,
4065 -- E => <entry index>;
4066 -- Uninterpreted_Data => P'Address;
4067 -- Mode => Asynchronous_Call;
4068 -- Block => Bnn);
4070 Stmt := First (Stmts);
4072 -- Skip assignments to temporaries created for in-out parameters.
4073 -- This makes unwarranted assumptions about the shape of the expanded
4074 -- tree for the call, and should be cleaned up ???
4076 while Nkind (Stmt) /= N_Procedure_Call_Statement loop
4077 Next (Stmt);
4078 end loop;
4080 Call := Stmt;
4082 Parm := First (Parameter_Associations (Call));
4083 while Present (Parm)
4084 and then not Is_RTE (Etype (Parm), RE_Call_Modes)
4085 loop
4086 Next (Parm);
4087 end loop;
4089 pragma Assert (Present (Parm));
4090 Rewrite (Parm, New_Reference_To (RTE (RE_Asynchronous_Call), Loc));
4091 Analyze (Parm);
4093 -- Append an if statement to execute the abortable part.
4094 -- if Enqueued (Bnn) then
4096 Append_To (Stmts,
4097 Make_Implicit_If_Statement (N,
4098 Condition => Make_Function_Call (Loc,
4099 Name => New_Reference_To (
4100 RTE (RE_Enqueued), Loc),
4101 Parameter_Associations => New_List (
4102 New_Reference_To (Cancel_Param, Loc))),
4103 Then_Statements => Astats));
4105 Abortable_Block :=
4106 Make_Block_Statement (Loc,
4107 Identifier => New_Reference_To (Blkent, Loc),
4108 Handled_Statement_Sequence =>
4109 Make_Handled_Sequence_Of_Statements (Loc,
4110 Statements => Stmts),
4111 Has_Created_Identifier => True,
4112 Is_Asynchronous_Call_Block => True);
4114 -- For the JVM call Update_Exception instead of Abort_Undefer.
4115 -- See 4jexcept.ads for an explanation.
4117 if Hostparm.Java_VM then
4118 Target_Undefer := RE_Update_Exception;
4119 Undefer_Args :=
4120 New_List (Make_Function_Call (Loc,
4121 Name => New_Occurrence_Of
4122 (RTE (RE_Current_Target_Exception), Loc)));
4123 else
4124 Target_Undefer := RE_Abort_Undefer;
4125 end if;
4127 Stmts := New_List (
4128 Make_Block_Statement (Loc,
4129 Handled_Statement_Sequence =>
4130 Make_Handled_Sequence_Of_Statements (Loc,
4131 Statements => New_List (
4132 Make_Implicit_Label_Declaration (Loc,
4133 Defining_Identifier => Blkent,
4134 Label_Construct => Abortable_Block),
4135 Abortable_Block),
4137 -- exception
4139 Exception_Handlers => New_List (
4140 Make_Exception_Handler (Loc,
4142 -- when Abort_Signal =>
4143 -- Abort_Undefer.all;
4145 Exception_Choices =>
4146 New_List (New_Reference_To (Stand.Abort_Signal, Loc)),
4147 Statements => New_List (
4148 Make_Procedure_Call_Statement (Loc,
4149 Name => New_Reference_To (
4150 RTE (Target_Undefer), Loc),
4151 Parameter_Associations => Undefer_Args)))))),
4153 -- if not Cancelled (Bnn) then
4154 -- triggered statements
4155 -- end if;
4157 Make_Implicit_If_Statement (N,
4158 Condition => Make_Op_Not (Loc,
4159 Right_Opnd =>
4160 Make_Function_Call (Loc,
4161 Name => New_Occurrence_Of (RTE (RE_Cancelled), Loc),
4162 Parameter_Associations => New_List (
4163 New_Occurrence_Of (Cancel_Param, Loc)))),
4164 Then_Statements => Tstats));
4166 -- Asynchronous task entry call
4168 else
4169 if No (Decls) then
4170 Decls := New_List;
4171 end if;
4173 B := Make_Defining_Identifier (Loc, Name_uB);
4175 -- Insert declaration of B in declarations of existing block
4177 Prepend_To (Decls,
4178 Make_Object_Declaration (Loc,
4179 Defining_Identifier => B,
4180 Object_Definition => New_Reference_To (Standard_Boolean, Loc)));
4182 Cancel_Param := Make_Defining_Identifier (Loc, Name_uC);
4184 -- Insert declaration of C in declarations of existing block
4186 Prepend_To (Decls,
4187 Make_Object_Declaration (Loc,
4188 Defining_Identifier => Cancel_Param,
4189 Object_Definition => New_Reference_To (Standard_Boolean, Loc)));
4191 -- Remove and save the call to Call_Simple
4193 Stmt := First (Stmts);
4195 -- Skip assignments to temporaries created for in-out parameters.
4196 -- This makes unwarranted assumptions about the shape of the expanded
4197 -- tree for the call, and should be cleaned up ???
4199 while Nkind (Stmt) /= N_Procedure_Call_Statement loop
4200 Next (Stmt);
4201 end loop;
4203 Call := Stmt;
4205 -- Create the inner block to protect the abortable part
4207 Hdle := New_List (
4208 Make_Exception_Handler (Loc,
4209 Exception_Choices =>
4210 New_List (New_Reference_To (Stand.Abort_Signal, Loc)),
4211 Statements => New_List (
4212 Make_Procedure_Call_Statement (Loc,
4213 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)))));
4215 Prepend_To (Astats,
4216 Make_Procedure_Call_Statement (Loc,
4217 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc)));
4219 Abortable_Block :=
4220 Make_Block_Statement (Loc,
4221 Identifier => New_Reference_To (Blkent, Loc),
4222 Handled_Statement_Sequence =>
4223 Make_Handled_Sequence_Of_Statements (Loc,
4224 Statements => Astats),
4225 Has_Created_Identifier => True,
4226 Is_Asynchronous_Call_Block => True);
4228 Insert_After (Call,
4229 Make_Block_Statement (Loc,
4230 Handled_Statement_Sequence =>
4231 Make_Handled_Sequence_Of_Statements (Loc,
4232 Statements => New_List (
4233 Make_Implicit_Label_Declaration (Loc,
4234 Defining_Identifier => Blkent,
4235 Label_Construct => Abortable_Block),
4236 Abortable_Block),
4237 Exception_Handlers => Hdle)));
4239 -- Create new call statement
4241 Parms := Parameter_Associations (Call);
4242 Append_To (Parms, New_Reference_To (RTE (RE_Asynchronous_Call), Loc));
4243 Append_To (Parms, New_Reference_To (B, Loc));
4244 Rewrite (Call,
4245 Make_Procedure_Call_Statement (Loc,
4246 Name => New_Reference_To (RTE (RE_Task_Entry_Call), Loc),
4247 Parameter_Associations => Parms));
4249 -- Construct statement sequence for new block
4251 Append_To (Stmts,
4252 Make_Implicit_If_Statement (N,
4253 Condition => Make_Op_Not (Loc,
4254 New_Reference_To (Cancel_Param, Loc)),
4255 Then_Statements => Tstats));
4257 -- Protected the call against abort
4259 Prepend_To (Stmts,
4260 Make_Procedure_Call_Statement (Loc,
4261 Name => New_Reference_To (RTE (RE_Abort_Defer), Loc),
4262 Parameter_Associations => Empty_List));
4263 end if;
4265 Set_Entry_Cancel_Parameter (Blkent, Cancel_Param);
4267 -- The result is the new block
4269 Rewrite (N_Orig,
4270 Make_Block_Statement (Loc,
4271 Declarations => Decls,
4272 Handled_Statement_Sequence =>
4273 Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
4275 Analyze (N_Orig);
4276 end Expand_N_Asynchronous_Select;
4278 -------------------------------------
4279 -- Expand_N_Conditional_Entry_Call --
4280 -------------------------------------
4282 -- The conditional task entry call is converted to a call to
4283 -- Task_Entry_Call:
4285 -- declare
4286 -- B : Boolean;
4287 -- P : parms := (parm, parm, parm);
4289 -- begin
4290 -- Task_Entry_Call
4291 -- (acceptor-task,
4292 -- entry-index,
4293 -- P'Address,
4294 -- Conditional_Call,
4295 -- B);
4296 -- parm := P.param;
4297 -- parm := P.param;
4298 -- ...
4299 -- if B then
4300 -- normal-statements
4301 -- else
4302 -- else-statements
4303 -- end if;
4304 -- end;
4306 -- For a description of the use of P and the assignments after the
4307 -- call, see Expand_N_Entry_Call_Statement. Note that the entry call
4308 -- of the conditional entry call has already been expanded (by the
4309 -- Expand_N_Entry_Call_Statement procedure) as follows:
4311 -- declare
4312 -- P : parms := (parm, parm, parm);
4313 -- begin
4314 -- ... info for in-out parameters
4315 -- Call_Simple (acceptor-task, entry-index, P'Address);
4316 -- parm := P.param;
4317 -- parm := P.param;
4318 -- ...
4319 -- end;
4321 -- so the task at hand is to convert the latter expansion into the former
4323 -- The conditional protected entry call is converted to a call to
4324 -- Protected_Entry_Call:
4326 -- declare
4327 -- P : parms := (parm, parm, parm);
4328 -- Bnn : Communications_Block;
4330 -- begin
4331 -- Protected_Entry_Call (
4332 -- Object => po._object'Access,
4333 -- E => <entry index>;
4334 -- Uninterpreted_Data => P'Address;
4335 -- Mode => Conditional_Call;
4336 -- Block => Bnn);
4337 -- parm := P.param;
4338 -- parm := P.param;
4339 -- ...
4340 -- if Cancelled (Bnn) then
4341 -- else-statements
4342 -- else
4343 -- normal-statements
4344 -- end if;
4345 -- end;
4347 -- As for tasks, the entry call of the conditional entry call has
4348 -- already been expanded (by the Expand_N_Entry_Call_Statement procedure)
4349 -- as follows:
4351 -- declare
4352 -- P : E1_Params := (param, param, param);
4353 -- Bnn : Communications_Block;
4355 -- begin
4356 -- Protected_Entry_Call (
4357 -- Object => po._object'Access,
4358 -- E => <entry index>;
4359 -- Uninterpreted_Data => P'Address;
4360 -- Mode => Simple_Call;
4361 -- Block => Bnn);
4362 -- parm := P.param;
4363 -- parm := P.param;
4364 -- ...
4365 -- end;
4367 procedure Expand_N_Conditional_Entry_Call (N : Node_Id) is
4368 Loc : constant Source_Ptr := Sloc (N);
4369 Alt : constant Node_Id := Entry_Call_Alternative (N);
4370 Blk : Node_Id := Entry_Call_Statement (Alt);
4371 Transient_Blk : Node_Id;
4373 Parms : List_Id;
4374 Parm : Node_Id;
4375 Call : Node_Id;
4376 Stmts : List_Id;
4377 B : Entity_Id;
4378 Decl : Node_Id;
4379 Stmt : Node_Id;
4381 begin
4382 -- As described above, The entry alternative is transformed into a
4383 -- block that contains the gnulli call, and possibly assignment
4384 -- statements for in-out parameters. The gnulli call may itself be
4385 -- rewritten into a transient block if some unconstrained parameters
4386 -- require it. We need to retrieve the call to complete its parameter
4387 -- list.
4389 Transient_Blk :=
4390 First_Real_Statement (Handled_Statement_Sequence (Blk));
4392 if Present (Transient_Blk)
4393 and then
4394 Nkind (Transient_Blk) = N_Block_Statement
4395 then
4396 Blk := Transient_Blk;
4397 end if;
4399 Stmts := Statements (Handled_Statement_Sequence (Blk));
4401 Stmt := First (Stmts);
4403 while Nkind (Stmt) /= N_Procedure_Call_Statement loop
4404 Next (Stmt);
4405 end loop;
4407 Call := Stmt;
4409 Parms := Parameter_Associations (Call);
4411 if Is_RTE (Entity (Name (Call)), RE_Protected_Entry_Call) then
4413 -- Substitute Conditional_Entry_Call for Simple_Call
4414 -- parameter.
4416 Parm := First (Parms);
4417 while Present (Parm)
4418 and then not Is_RTE (Etype (Parm), RE_Call_Modes)
4419 loop
4420 Next (Parm);
4421 end loop;
4423 pragma Assert (Present (Parm));
4424 Rewrite (Parm, New_Reference_To (RTE (RE_Conditional_Call), Loc));
4426 Analyze (Parm);
4428 -- Find the Communication_Block parameter for the call
4429 -- to the Cancelled function.
4431 Decl := First (Declarations (Blk));
4432 while Present (Decl)
4433 and then not
4434 Is_RTE (Etype (Object_Definition (Decl)), RE_Communication_Block)
4435 loop
4436 Next (Decl);
4437 end loop;
4439 -- Add an if statement to execute the else part if the call
4440 -- does not succeed (as indicated by the Cancelled predicate).
4442 Append_To (Stmts,
4443 Make_Implicit_If_Statement (N,
4444 Condition => Make_Function_Call (Loc,
4445 Name => New_Reference_To (RTE (RE_Cancelled), Loc),
4446 Parameter_Associations => New_List (
4447 New_Reference_To (Defining_Identifier (Decl), Loc))),
4448 Then_Statements => Else_Statements (N),
4449 Else_Statements => Statements (Alt)));
4451 else
4452 B := Make_Defining_Identifier (Loc, Name_uB);
4454 -- Insert declaration of B in declarations of existing block
4456 if No (Declarations (Blk)) then
4457 Set_Declarations (Blk, New_List);
4458 end if;
4460 Prepend_To (Declarations (Blk),
4461 Make_Object_Declaration (Loc,
4462 Defining_Identifier => B,
4463 Object_Definition => New_Reference_To (Standard_Boolean, Loc)));
4465 -- Create new call statement
4467 Append_To (Parms, New_Reference_To (RTE (RE_Conditional_Call), Loc));
4468 Append_To (Parms, New_Reference_To (B, Loc));
4470 Rewrite (Call,
4471 Make_Procedure_Call_Statement (Loc,
4472 Name => New_Reference_To (RTE (RE_Task_Entry_Call), Loc),
4473 Parameter_Associations => Parms));
4475 -- Construct statement sequence for new block
4477 Append_To (Stmts,
4478 Make_Implicit_If_Statement (N,
4479 Condition => New_Reference_To (B, Loc),
4480 Then_Statements => Statements (Alt),
4481 Else_Statements => Else_Statements (N)));
4483 end if;
4485 -- The result is the new block
4487 Rewrite (N,
4488 Make_Block_Statement (Loc,
4489 Declarations => Declarations (Blk),
4490 Handled_Statement_Sequence =>
4491 Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
4493 Analyze (N);
4494 end Expand_N_Conditional_Entry_Call;
4496 ---------------------------------------
4497 -- Expand_N_Delay_Relative_Statement --
4498 ---------------------------------------
4500 -- Delay statement is implemented as a procedure call to Delay_For
4501 -- defined in Ada.Calendar.Delays in order to reduce the overhead of
4502 -- simple delays imposed by the use of Protected Objects.
4504 procedure Expand_N_Delay_Relative_Statement (N : Node_Id) is
4505 Loc : constant Source_Ptr := Sloc (N);
4507 begin
4508 Rewrite (N,
4509 Make_Procedure_Call_Statement (Loc,
4510 Name => New_Reference_To (RTE (RO_CA_Delay_For), Loc),
4511 Parameter_Associations => New_List (Expression (N))));
4512 Analyze (N);
4513 end Expand_N_Delay_Relative_Statement;
4515 ------------------------------------
4516 -- Expand_N_Delay_Until_Statement --
4517 ------------------------------------
4519 -- Delay Until statement is implemented as a procedure call to
4520 -- Delay_Until defined in Ada.Calendar.Delays and Ada.Real_Time.Delays.
4522 procedure Expand_N_Delay_Until_Statement (N : Node_Id) is
4523 Loc : constant Source_Ptr := Sloc (N);
4524 Typ : Entity_Id;
4526 begin
4527 if Is_RTE (Base_Type (Etype (Expression (N))), RO_CA_Time) then
4528 Typ := RTE (RO_CA_Delay_Until);
4529 else
4530 Typ := RTE (RO_RT_Delay_Until);
4531 end if;
4533 Rewrite (N,
4534 Make_Procedure_Call_Statement (Loc,
4535 Name => New_Reference_To (Typ, Loc),
4536 Parameter_Associations => New_List (Expression (N))));
4538 Analyze (N);
4539 end Expand_N_Delay_Until_Statement;
4541 -------------------------
4542 -- Expand_N_Entry_Body --
4543 -------------------------
4545 procedure Expand_N_Entry_Body (N : Node_Id) is
4546 Loc : constant Source_Ptr := Sloc (N);
4547 Dec : constant Node_Id := Parent (Current_Scope);
4548 Ent_Formals : constant Node_Id := Entry_Body_Formal_Part (N);
4549 Index_Spec : constant Node_Id :=
4550 Entry_Index_Specification (Ent_Formals);
4551 Next_Op : Node_Id;
4552 First_Decl : constant Node_Id := First (Declarations (N));
4553 Index_Decl : List_Id;
4555 begin
4556 -- Add the renamings for private declarations and discriminants
4558 Add_Discriminal_Declarations
4559 (Declarations (N), Defining_Identifier (Dec), Name_uObject, Loc);
4560 Add_Private_Declarations
4561 (Declarations (N), Defining_Identifier (Dec), Name_uObject, Loc);
4563 if Present (Index_Spec) then
4564 Index_Decl :=
4565 Index_Constant_Declaration
4567 Defining_Identifier (Index_Spec), Defining_Identifier (Dec));
4569 -- If the entry has local declarations, insert index declaration
4570 -- before them, because the index may be used therein.
4572 if Present (First_Decl) then
4573 Insert_List_Before (First_Decl, Index_Decl);
4574 else
4575 Append_List_To (Declarations (N), Index_Decl);
4576 end if;
4577 end if;
4579 -- Associate privals and discriminals with the next protected
4580 -- operation body to be expanded. These are used to expand
4581 -- references to private data objects and discriminants,
4582 -- respectively.
4584 Next_Op := Next_Protected_Operation (N);
4586 if Present (Next_Op) then
4587 Set_Privals (Dec, Next_Op, Loc);
4588 Set_Discriminals (Dec);
4589 end if;
4590 end Expand_N_Entry_Body;
4592 -----------------------------------
4593 -- Expand_N_Entry_Call_Statement --
4594 -----------------------------------
4596 -- An entry call is expanded into GNARLI calls to implement
4597 -- a simple entry call (see Build_Simple_Entry_Call).
4599 procedure Expand_N_Entry_Call_Statement (N : Node_Id) is
4600 Concval : Node_Id;
4601 Ename : Node_Id;
4602 Index : Node_Id;
4604 begin
4605 if No_Run_Time_Mode then
4606 Error_Msg_CRT ("entry call", N);
4607 return;
4608 end if;
4610 -- If this entry call is part of an asynchronous select, don't
4611 -- expand it here; it will be expanded with the select statement.
4612 -- Don't expand timed entry calls either, as they are translated
4613 -- into asynchronous entry calls.
4615 -- ??? This whole approach is questionable; it may be better
4616 -- to go back to allowing the expansion to take place and then
4617 -- attempting to fix it up in Expand_N_Asynchronous_Select.
4618 -- The tricky part is figuring out whether the expanded
4619 -- call is on a task or protected entry.
4621 if (Nkind (Parent (N)) /= N_Triggering_Alternative
4622 or else N /= Triggering_Statement (Parent (N)))
4623 and then (Nkind (Parent (N)) /= N_Entry_Call_Alternative
4624 or else N /= Entry_Call_Statement (Parent (N))
4625 or else Nkind (Parent (Parent (N))) /= N_Timed_Entry_Call)
4626 then
4627 Extract_Entry (N, Concval, Ename, Index);
4628 Build_Simple_Entry_Call (N, Concval, Ename, Index);
4629 end if;
4630 end Expand_N_Entry_Call_Statement;
4632 --------------------------------
4633 -- Expand_N_Entry_Declaration --
4634 --------------------------------
4636 -- If there are parameters, then first, each of the formals is marked
4637 -- by setting Is_Entry_Formal. Next a record type is built which is
4638 -- used to hold the parameter values. The name of this record type is
4639 -- entryP where entry is the name of the entry, with an additional
4640 -- corresponding access type called entryPA. The record type has matching
4641 -- components for each formal (the component names are the same as the
4642 -- formal names). For elementary types, the component type matches the
4643 -- formal type. For composite types, an access type is declared (with
4644 -- the name formalA) which designates the formal type, and the type of
4645 -- the component is this access type. Finally the Entry_Component of
4646 -- each formal is set to reference the corresponding record component.
4648 procedure Expand_N_Entry_Declaration (N : Node_Id) is
4649 Loc : constant Source_Ptr := Sloc (N);
4650 Entry_Ent : constant Entity_Id := Defining_Identifier (N);
4651 Components : List_Id;
4652 Formal : Node_Id;
4653 Ftype : Entity_Id;
4654 Last_Decl : Node_Id;
4655 Component : Entity_Id;
4656 Ctype : Entity_Id;
4657 Decl : Node_Id;
4658 Rec_Ent : Entity_Id;
4659 Acc_Ent : Entity_Id;
4661 begin
4662 Formal := First_Formal (Entry_Ent);
4663 Last_Decl := N;
4665 -- Most processing is done only if parameters are present
4667 if Present (Formal) then
4668 Components := New_List;
4670 -- Loop through formals
4672 while Present (Formal) loop
4673 Set_Is_Entry_Formal (Formal);
4674 Component :=
4675 Make_Defining_Identifier (Sloc (Formal), Chars (Formal));
4676 Set_Entry_Component (Formal, Component);
4677 Set_Entry_Formal (Component, Formal);
4678 Ftype := Etype (Formal);
4680 -- Declare new access type and then append
4682 Ctype :=
4683 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4685 Decl :=
4686 Make_Full_Type_Declaration (Loc,
4687 Defining_Identifier => Ctype,
4688 Type_Definition =>
4689 Make_Access_To_Object_Definition (Loc,
4690 All_Present => True,
4691 Constant_Present => Ekind (Formal) = E_In_Parameter,
4692 Subtype_Indication => New_Reference_To (Ftype, Loc)));
4694 Insert_After (Last_Decl, Decl);
4695 Last_Decl := Decl;
4697 Append_To (Components,
4698 Make_Component_Declaration (Loc,
4699 Defining_Identifier => Component,
4700 Component_Definition =>
4701 Make_Component_Definition (Loc,
4702 Aliased_Present => False,
4703 Subtype_Indication => New_Reference_To (Ctype, Loc))));
4705 Next_Formal_With_Extras (Formal);
4706 end loop;
4708 -- Create the Entry_Parameter_Record declaration
4710 Rec_Ent :=
4711 Make_Defining_Identifier (Loc, New_Internal_Name ('P'));
4713 Decl :=
4714 Make_Full_Type_Declaration (Loc,
4715 Defining_Identifier => Rec_Ent,
4716 Type_Definition =>
4717 Make_Record_Definition (Loc,
4718 Component_List =>
4719 Make_Component_List (Loc,
4720 Component_Items => Components)));
4722 Insert_After (Last_Decl, Decl);
4723 Last_Decl := Decl;
4725 -- Construct and link in the corresponding access type
4727 Acc_Ent :=
4728 Make_Defining_Identifier (Loc, New_Internal_Name ('A'));
4730 Set_Entry_Parameters_Type (Entry_Ent, Acc_Ent);
4732 Decl :=
4733 Make_Full_Type_Declaration (Loc,
4734 Defining_Identifier => Acc_Ent,
4735 Type_Definition =>
4736 Make_Access_To_Object_Definition (Loc,
4737 All_Present => True,
4738 Subtype_Indication => New_Reference_To (Rec_Ent, Loc)));
4740 Insert_After (Last_Decl, Decl);
4741 Last_Decl := Decl;
4742 end if;
4743 end Expand_N_Entry_Declaration;
4745 -----------------------------
4746 -- Expand_N_Protected_Body --
4747 -----------------------------
4749 -- Protected bodies are expanded to the completion of the subprograms
4750 -- created for the corresponding protected type. These are a protected
4751 -- and unprotected version of each protected subprogram in the object,
4752 -- a function to calculate each entry barrier, and a procedure to
4753 -- execute the sequence of statements of each protected entry body.
4754 -- For example, for protected type ptype:
4756 -- function entB
4757 -- (O : System.Address;
4758 -- E : Protected_Entry_Index)
4759 -- return Boolean
4760 -- is
4761 -- <discriminant renamings>
4762 -- <private object renamings>
4763 -- begin
4764 -- return <barrier expression>;
4765 -- end entB;
4767 -- procedure pprocN (_object : in out poV;...) is
4768 -- <discriminant renamings>
4769 -- <private object renamings>
4770 -- begin
4771 -- <sequence of statements>
4772 -- end pprocN;
4774 -- procedure pproc (_object : in out poV;...) is
4775 -- procedure _clean is
4776 -- Pn : Boolean;
4777 -- begin
4778 -- ptypeS (_object, Pn);
4779 -- Unlock (_object._object'Access);
4780 -- Abort_Undefer.all;
4781 -- end _clean;
4783 -- begin
4784 -- Abort_Defer.all;
4785 -- Lock (_object._object'Access);
4786 -- pprocN (_object;...);
4787 -- at end
4788 -- _clean;
4789 -- end pproc;
4791 -- function pfuncN (_object : poV;...) return Return_Type is
4792 -- <discriminant renamings>
4793 -- <private object renamings>
4794 -- begin
4795 -- <sequence of statements>
4796 -- end pfuncN;
4798 -- function pfunc (_object : poV) return Return_Type is
4799 -- procedure _clean is
4800 -- begin
4801 -- Unlock (_object._object'Access);
4802 -- Abort_Undefer.all;
4803 -- end _clean;
4805 -- begin
4806 -- Abort_Defer.all;
4807 -- Lock (_object._object'Access);
4808 -- return pfuncN (_object);
4810 -- at end
4811 -- _clean;
4812 -- end pfunc;
4814 -- procedure entE
4815 -- (O : System.Address;
4816 -- P : System.Address;
4817 -- E : Protected_Entry_Index)
4818 -- is
4819 -- <discriminant renamings>
4820 -- <private object renamings>
4821 -- type poVP is access poV;
4822 -- _Object : ptVP := ptVP!(O);
4824 -- begin
4825 -- begin
4826 -- <statement sequence>
4827 -- Complete_Entry_Body (_Object._Object);
4828 -- exception
4829 -- when all others =>
4830 -- Exceptional_Complete_Entry_Body (
4831 -- _Object._Object, Get_GNAT_Exception);
4832 -- end;
4833 -- end entE;
4835 -- The type poV is the record created for the protected type to hold
4836 -- the state of the protected object.
4838 procedure Expand_N_Protected_Body (N : Node_Id) is
4839 Pid : constant Entity_Id := Corresponding_Spec (N);
4840 Has_Entries : Boolean := False;
4841 Op_Decl : Node_Id;
4842 Op_Body : Node_Id;
4843 Op_Id : Entity_Id;
4844 New_Op_Body : Node_Id;
4845 Current_Node : Node_Id;
4846 Num_Entries : Natural := 0;
4848 begin
4849 if No_Run_Time_Mode then
4850 Error_Msg_CRT ("protected body", N);
4851 return;
4852 end if;
4854 if Nkind (Parent (N)) = N_Subunit then
4856 -- This is the proper body corresponding to a stub. The declarations
4857 -- must be inserted at the point of the stub, which is in the decla-
4858 -- rative part of the parent unit.
4860 Current_Node := Corresponding_Stub (Parent (N));
4862 else
4863 Current_Node := N;
4864 end if;
4866 Op_Body := First (Declarations (N));
4868 -- The protected body is replaced with the bodies of its
4869 -- protected operations, and the declarations for internal objects
4870 -- that may have been created for entry family bounds.
4872 Rewrite (N, Make_Null_Statement (Sloc (N)));
4873 Analyze (N);
4875 while Present (Op_Body) loop
4876 case Nkind (Op_Body) is
4877 when N_Subprogram_Declaration =>
4878 null;
4880 when N_Subprogram_Body =>
4882 -- Exclude functions created to analyze defaults
4884 if not Is_Eliminated (Defining_Entity (Op_Body))
4885 and then not Is_Eliminated (Corresponding_Spec (Op_Body))
4886 then
4887 New_Op_Body :=
4888 Build_Unprotected_Subprogram_Body (Op_Body, Pid);
4890 Insert_After (Current_Node, New_Op_Body);
4891 Current_Node := New_Op_Body;
4892 Analyze (New_Op_Body);
4894 Update_Prival_Subtypes (New_Op_Body);
4896 -- Build the corresponding protected operation only if
4897 -- this is a visible operation of the type, or if it is
4898 -- an interrupt handler. Otherwise it is only callable
4899 -- from within the object, and the unprotected version
4900 -- is sufficient.
4902 if Present (Corresponding_Spec (Op_Body)) then
4903 Op_Decl :=
4904 Unit_Declaration_Node (Corresponding_Spec (Op_Body));
4906 if Nkind (Parent (Op_Decl)) = N_Protected_Definition
4907 and then
4908 (List_Containing (Op_Decl) =
4909 Visible_Declarations (Parent (Op_Decl))
4910 or else
4911 Is_Interrupt_Handler
4912 (Corresponding_Spec (Op_Body)))
4913 then
4914 New_Op_Body :=
4915 Build_Protected_Subprogram_Body (
4916 Op_Body, Pid, Specification (New_Op_Body));
4918 Insert_After (Current_Node, New_Op_Body);
4919 Analyze (New_Op_Body);
4920 end if;
4921 end if;
4922 end if;
4924 when N_Entry_Body =>
4925 Op_Id := Defining_Identifier (Op_Body);
4926 Has_Entries := True;
4927 Num_Entries := Num_Entries + 1;
4929 New_Op_Body := Build_Protected_Entry (Op_Body, Op_Id, Pid);
4931 Insert_After (Current_Node, New_Op_Body);
4932 Current_Node := New_Op_Body;
4933 Analyze (New_Op_Body);
4935 Update_Prival_Subtypes (New_Op_Body);
4937 when N_Implicit_Label_Declaration =>
4938 null;
4940 when N_Itype_Reference =>
4941 Insert_After (Current_Node, New_Copy (Op_Body));
4943 when N_Freeze_Entity =>
4944 New_Op_Body := New_Copy (Op_Body);
4946 if Present (Entity (Op_Body))
4947 and then Freeze_Node (Entity (Op_Body)) = Op_Body
4948 then
4949 Set_Freeze_Node (Entity (Op_Body), New_Op_Body);
4950 end if;
4952 Insert_After (Current_Node, New_Op_Body);
4953 Current_Node := New_Op_Body;
4954 Analyze (New_Op_Body);
4956 when N_Pragma =>
4957 New_Op_Body := New_Copy (Op_Body);
4958 Insert_After (Current_Node, New_Op_Body);
4959 Current_Node := New_Op_Body;
4960 Analyze (New_Op_Body);
4962 when N_Object_Declaration =>
4963 pragma Assert (not Comes_From_Source (Op_Body));
4964 New_Op_Body := New_Copy (Op_Body);
4965 Insert_After (Current_Node, New_Op_Body);
4966 Current_Node := New_Op_Body;
4967 Analyze (New_Op_Body);
4969 when others =>
4970 raise Program_Error;
4972 end case;
4974 Next (Op_Body);
4975 end loop;
4977 -- Finally, create the body of the function that maps an entry index
4978 -- into the corresponding body index, except when there is no entry,
4979 -- or in a ravenscar-like profile (no abort, no entry queue, 1 entry)
4981 if Has_Entries
4982 and then (Abort_Allowed
4983 or else Restriction_Active (No_Entry_Queue) = False
4984 or else Num_Entries > 1)
4985 then
4986 New_Op_Body := Build_Find_Body_Index (Pid);
4987 Insert_After (Current_Node, New_Op_Body);
4988 Analyze (New_Op_Body);
4989 end if;
4990 end Expand_N_Protected_Body;
4992 -----------------------------------------
4993 -- Expand_N_Protected_Type_Declaration --
4994 -----------------------------------------
4996 -- First we create a corresponding record type declaration used to
4997 -- represent values of this protected type.
4998 -- The general form of this type declaration is
5000 -- type poV (discriminants) is record
5001 -- _Object : aliased <kind>Protection
5002 -- [(<entry count> [, <handler count>])];
5003 -- [entry_family : array (bounds) of Void;]
5004 -- <private data fields>
5005 -- end record;
5007 -- The discriminants are present only if the corresponding protected
5008 -- type has discriminants, and they exactly mirror the protected type
5009 -- discriminants. The private data fields similarly mirror the
5010 -- private declarations of the protected type.
5012 -- The Object field is always present. It contains RTS specific data
5013 -- used to control the protected object. It is declared as Aliased
5014 -- so that it can be passed as a pointer to the RTS. This allows the
5015 -- protected record to be referenced within RTS data structures.
5016 -- An appropriate Protection type and discriminant are generated.
5018 -- The Service field is present for protected objects with entries. It
5019 -- contains sufficient information to allow the entry service procedure
5020 -- for this object to be called when the object is not known till runtime.
5022 -- One entry_family component is present for each entry family in the
5023 -- task definition (see Expand_N_Task_Type_Declaration).
5025 -- When a protected object is declared, an instance of the protected type
5026 -- value record is created. The elaboration of this declaration creates
5027 -- the correct bounds for the entry families, and also evaluates the
5028 -- priority expression if needed. The initialization routine for
5029 -- the protected type itself then calls Initialize_Protection with
5030 -- appropriate parameters to initialize the value of the Task_Id field.
5031 -- Install_Handlers may be also called if a pragma Attach_Handler applies.
5033 -- Note: this record is passed to the subprograms created by the
5034 -- expansion of protected subprograms and entries. It is an in parameter
5035 -- to protected functions and an in out parameter to procedures and
5036 -- entry bodies. The Entity_Id for this created record type is placed
5037 -- in the Corresponding_Record_Type field of the associated protected
5038 -- type entity.
5040 -- Next we create a procedure specifications for protected subprograms
5041 -- and entry bodies. For each protected subprograms two subprograms are
5042 -- created, an unprotected and a protected version. The unprotected
5043 -- version is called from within other operations of the same protected
5044 -- object.
5046 -- We also build the call to register the procedure if a pragma
5047 -- Interrupt_Handler applies.
5049 -- A single subprogram is created to service all entry bodies; it has an
5050 -- additional boolean out parameter indicating that the previous entry
5051 -- call made by the current task was serviced immediately, i.e. not by
5052 -- proxy. The O parameter contains a pointer to a record object of the
5053 -- type described above. An untyped interface is used here to allow this
5054 -- procedure to be called in places where the type of the object to be
5055 -- serviced is not known. This must be done, for example, when a call
5056 -- that may have been requeued is cancelled; the corresponding object
5057 -- must be serviced, but which object that is not known till runtime.
5059 -- procedure ptypeS
5060 -- (O : System.Address; P : out Boolean);
5061 -- procedure pprocN (_object : in out poV);
5062 -- procedure pproc (_object : in out poV);
5063 -- function pfuncN (_object : poV);
5064 -- function pfunc (_object : poV);
5065 -- ...
5067 -- Note that this must come after the record type declaration, since
5068 -- the specs refer to this type.
5070 procedure Expand_N_Protected_Type_Declaration (N : Node_Id) is
5071 Loc : constant Source_Ptr := Sloc (N);
5072 Prottyp : constant Entity_Id := Defining_Identifier (N);
5073 Protnm : constant Name_Id := Chars (Prottyp);
5075 Pdef : constant Node_Id := Protected_Definition (N);
5076 -- This contains two lists; one for visible and one for private decls
5078 Rec_Decl : Node_Id;
5079 Cdecls : List_Id;
5080 Discr_Map : constant Elist_Id := New_Elmt_List;
5081 Priv : Node_Id;
5082 Pent : Entity_Id;
5083 New_Priv : Node_Id;
5084 Comp : Node_Id;
5085 Comp_Id : Entity_Id;
5086 Sub : Node_Id;
5087 Current_Node : Node_Id := N;
5088 Bdef : Entity_Id := Empty; -- avoid uninit warning
5089 Edef : Entity_Id := Empty; -- avoid uninit warning
5090 Entries_Aggr : Node_Id;
5091 Body_Id : Entity_Id;
5092 Body_Arr : Node_Id;
5093 E_Count : Int;
5094 Object_Comp : Node_Id;
5096 procedure Register_Handler;
5097 -- for a protected operation that is an interrupt handler, add the
5098 -- freeze action that will register it as such.
5100 ----------------------
5101 -- Register_Handler --
5102 ----------------------
5104 procedure Register_Handler is
5106 -- All semantic checks already done in Sem_Prag
5108 Prot_Proc : constant Entity_Id :=
5109 Defining_Unit_Name
5110 (Specification (Current_Node));
5112 Proc_Address : constant Node_Id :=
5113 Make_Attribute_Reference (Loc,
5114 Prefix => New_Reference_To (Prot_Proc, Loc),
5115 Attribute_Name => Name_Address);
5117 RTS_Call : constant Entity_Id :=
5118 Make_Procedure_Call_Statement (Loc,
5119 Name =>
5120 New_Reference_To (
5121 RTE (RE_Register_Interrupt_Handler), Loc),
5122 Parameter_Associations =>
5123 New_List (Proc_Address));
5124 begin
5125 Append_Freeze_Action (Prot_Proc, RTS_Call);
5126 end Register_Handler;
5128 -- Start of processing for Expand_N_Protected_Type_Declaration
5130 begin
5131 if Present (Corresponding_Record_Type (Prottyp)) then
5132 return;
5133 else
5134 Rec_Decl := Build_Corresponding_Record (N, Prottyp, Loc);
5135 Cdecls := Component_Items
5136 (Component_List (Type_Definition (Rec_Decl)));
5137 end if;
5139 Qualify_Entity_Names (N);
5141 -- If the type has discriminants, their occurrences in the declaration
5142 -- have been replaced by the corresponding discriminals. For components
5143 -- that are constrained by discriminants, their homologues in the
5144 -- corresponding record type must refer to the discriminants of that
5145 -- record, so we must apply a new renaming to subtypes_indications:
5147 -- protected discriminant => discriminal => record discriminant.
5148 -- This replacement is not applied to default expressions, for which
5149 -- the discriminal is correct.
5151 if Has_Discriminants (Prottyp) then
5152 declare
5153 Disc : Entity_Id;
5154 Decl : Node_Id;
5156 begin
5157 Disc := First_Discriminant (Prottyp);
5158 Decl := First (Discriminant_Specifications (Rec_Decl));
5160 while Present (Disc) loop
5161 Append_Elmt (Discriminal (Disc), Discr_Map);
5162 Append_Elmt (Defining_Identifier (Decl), Discr_Map);
5163 Next_Discriminant (Disc);
5164 Next (Decl);
5165 end loop;
5166 end;
5167 end if;
5169 -- Fill in the component declarations
5171 -- Add components for entry families. For each entry family,
5172 -- create an anonymous type declaration with the same size, and
5173 -- analyze the type.
5175 Collect_Entry_Families (Loc, Cdecls, Current_Node, Prottyp);
5177 -- Prepend the _Object field with the right type to the component
5178 -- list. We need to compute the number of entries, and in some cases
5179 -- the number of Attach_Handler pragmas.
5181 declare
5182 Ritem : Node_Id;
5183 Num_Attach_Handler : Int := 0;
5184 Protection_Subtype : Node_Id;
5185 Entry_Count_Expr : constant Node_Id :=
5186 Build_Entry_Count_Expression
5187 (Prottyp, Cdecls, Loc);
5189 begin
5190 if Has_Attach_Handler (Prottyp) then
5191 Ritem := First_Rep_Item (Prottyp);
5192 while Present (Ritem) loop
5193 if Nkind (Ritem) = N_Pragma
5194 and then Chars (Ritem) = Name_Attach_Handler
5195 then
5196 Num_Attach_Handler := Num_Attach_Handler + 1;
5197 end if;
5199 Next_Rep_Item (Ritem);
5200 end loop;
5202 if Restricted_Profile then
5203 if Has_Entries (Prottyp) then
5204 Protection_Subtype :=
5205 New_Reference_To (RTE (RE_Protection_Entry), Loc);
5206 else
5207 Protection_Subtype :=
5208 New_Reference_To (RTE (RE_Protection), Loc);
5209 end if;
5210 else
5211 Protection_Subtype :=
5212 Make_Subtype_Indication
5213 (Sloc => Loc,
5214 Subtype_Mark =>
5215 New_Reference_To
5216 (RTE (RE_Static_Interrupt_Protection), Loc),
5217 Constraint =>
5218 Make_Index_Or_Discriminant_Constraint (
5219 Sloc => Loc,
5220 Constraints => New_List (
5221 Entry_Count_Expr,
5222 Make_Integer_Literal (Loc, Num_Attach_Handler))));
5223 end if;
5225 elsif Has_Interrupt_Handler (Prottyp) then
5226 Protection_Subtype :=
5227 Make_Subtype_Indication (
5228 Sloc => Loc,
5229 Subtype_Mark => New_Reference_To
5230 (RTE (RE_Dynamic_Interrupt_Protection), Loc),
5231 Constraint =>
5232 Make_Index_Or_Discriminant_Constraint (
5233 Sloc => Loc,
5234 Constraints => New_List (Entry_Count_Expr)));
5236 elsif Has_Entries (Prottyp) then
5237 if Abort_Allowed
5238 or else Restriction_Active (No_Entry_Queue) = False
5239 or else Number_Entries (Prottyp) > 1
5240 then
5241 Protection_Subtype :=
5242 Make_Subtype_Indication (
5243 Sloc => Loc,
5244 Subtype_Mark =>
5245 New_Reference_To (RTE (RE_Protection_Entries), Loc),
5246 Constraint =>
5247 Make_Index_Or_Discriminant_Constraint (
5248 Sloc => Loc,
5249 Constraints => New_List (Entry_Count_Expr)));
5251 else
5252 Protection_Subtype :=
5253 New_Reference_To (RTE (RE_Protection_Entry), Loc);
5254 end if;
5256 else
5257 Protection_Subtype := New_Reference_To (RTE (RE_Protection), Loc);
5258 end if;
5260 Object_Comp :=
5261 Make_Component_Declaration (Loc,
5262 Defining_Identifier =>
5263 Make_Defining_Identifier (Loc, Name_uObject),
5264 Component_Definition =>
5265 Make_Component_Definition (Loc,
5266 Aliased_Present => True,
5267 Subtype_Indication => Protection_Subtype));
5268 end;
5270 pragma Assert (Present (Pdef));
5272 -- Add private field components
5274 if Present (Private_Declarations (Pdef)) then
5275 Priv := First (Private_Declarations (Pdef));
5277 while Present (Priv) loop
5279 if Nkind (Priv) = N_Component_Declaration then
5280 Pent := Defining_Identifier (Priv);
5281 New_Priv :=
5282 Make_Component_Declaration (Loc,
5283 Defining_Identifier =>
5284 Make_Defining_Identifier (Sloc (Pent), Chars (Pent)),
5285 Component_Definition =>
5286 Make_Component_Definition (Sloc (Pent),
5287 Aliased_Present => False,
5288 Subtype_Indication =>
5289 New_Copy_Tree (Subtype_Indication
5290 (Component_Definition (Priv)),
5291 Discr_Map)),
5292 Expression => Expression (Priv));
5294 Append_To (Cdecls, New_Priv);
5296 elsif Nkind (Priv) = N_Subprogram_Declaration then
5298 -- Make the unprotected version of the subprogram available
5299 -- for expansion of intra object calls. There is need for
5300 -- a protected version only if the subprogram is an interrupt
5301 -- handler, otherwise this operation can only be called from
5302 -- within the body.
5304 Sub :=
5305 Make_Subprogram_Declaration (Loc,
5306 Specification =>
5307 Build_Protected_Sub_Specification
5308 (Priv, Prottyp, Unprotected => True));
5310 Insert_After (Current_Node, Sub);
5311 Analyze (Sub);
5313 Set_Protected_Body_Subprogram
5314 (Defining_Unit_Name (Specification (Priv)),
5315 Defining_Unit_Name (Specification (Sub)));
5317 Current_Node := Sub;
5318 if Is_Interrupt_Handler
5319 (Defining_Unit_Name (Specification (Priv)))
5320 then
5321 Sub :=
5322 Make_Subprogram_Declaration (Loc,
5323 Specification =>
5324 Build_Protected_Sub_Specification
5325 (Priv, Prottyp, Unprotected => False));
5327 Insert_After (Current_Node, Sub);
5328 Analyze (Sub);
5329 Current_Node := Sub;
5331 if not Restricted_Profile then
5332 Register_Handler;
5333 end if;
5334 end if;
5335 end if;
5337 Next (Priv);
5338 end loop;
5339 end if;
5341 -- Put the _Object component after the private component so that it
5342 -- be finalized early as required by 9.4 (20)
5344 Append_To (Cdecls, Object_Comp);
5346 Insert_After (Current_Node, Rec_Decl);
5347 Current_Node := Rec_Decl;
5349 -- Analyze the record declaration immediately after construction,
5350 -- because the initialization procedure is needed for single object
5351 -- declarations before the next entity is analyzed (the freeze call
5352 -- that generates this initialization procedure is found below).
5354 Analyze (Rec_Decl, Suppress => All_Checks);
5356 -- Collect pointers to entry bodies and their barriers, to be placed
5357 -- in the Entry_Bodies_Array for the type. For each entry/family we
5358 -- add an expression to the aggregate which is the initial value of
5359 -- this array. The array is declared after all protected subprograms.
5361 if Has_Entries (Prottyp) then
5362 Entries_Aggr :=
5363 Make_Aggregate (Loc, Expressions => New_List);
5365 else
5366 Entries_Aggr := Empty;
5367 end if;
5369 -- Build two new procedure specifications for each protected
5370 -- subprogram; one to call from outside the object and one to
5371 -- call from inside. Build a barrier function and an entry
5372 -- body action procedure specification for each protected entry.
5373 -- Initialize the entry body array. If subprogram is flagged as
5374 -- eliminated, do not generate any internal operations.
5376 E_Count := 0;
5378 Comp := First (Visible_Declarations (Pdef));
5380 while Present (Comp) loop
5381 if Nkind (Comp) = N_Subprogram_Declaration
5382 and then not Is_Eliminated (Defining_Entity (Comp))
5383 then
5384 Sub :=
5385 Make_Subprogram_Declaration (Loc,
5386 Specification =>
5387 Build_Protected_Sub_Specification
5388 (Comp, Prottyp, Unprotected => True));
5390 Insert_After (Current_Node, Sub);
5391 Analyze (Sub);
5393 Set_Protected_Body_Subprogram
5394 (Defining_Unit_Name (Specification (Comp)),
5395 Defining_Unit_Name (Specification (Sub)));
5397 -- Make the protected version of the subprogram available
5398 -- for expansion of external calls.
5400 Current_Node := Sub;
5402 Sub :=
5403 Make_Subprogram_Declaration (Loc,
5404 Specification =>
5405 Build_Protected_Sub_Specification
5406 (Comp, Prottyp, Unprotected => False));
5408 Insert_After (Current_Node, Sub);
5409 Analyze (Sub);
5410 Current_Node := Sub;
5412 -- If a pragma Interrupt_Handler applies, build and add
5413 -- a call to Register_Interrupt_Handler to the freezing actions
5414 -- of the protected version (Current_Node) of the subprogram:
5415 -- system.interrupts.register_interrupt_handler
5416 -- (prot_procP'address);
5418 if not Restricted_Profile
5419 and then Is_Interrupt_Handler
5420 (Defining_Unit_Name (Specification (Comp)))
5421 then
5422 Register_Handler;
5423 end if;
5425 elsif Nkind (Comp) = N_Entry_Declaration then
5426 E_Count := E_Count + 1;
5427 Comp_Id := Defining_Identifier (Comp);
5428 Set_Privals_Chain (Comp_Id, New_Elmt_List);
5429 Edef :=
5430 Make_Defining_Identifier (Loc,
5431 Build_Selected_Name
5432 (Protnm,
5433 New_External_Name (Chars (Comp_Id), Suffix_Index => -1),
5434 'E'));
5435 Sub :=
5436 Make_Subprogram_Declaration (Loc,
5437 Specification =>
5438 Build_Protected_Entry_Specification (Edef, Comp_Id, Loc));
5440 Insert_After (Current_Node, Sub);
5441 Analyze (Sub);
5443 Set_Protected_Body_Subprogram (
5444 Defining_Identifier (Comp),
5445 Defining_Unit_Name (Specification (Sub)));
5447 Current_Node := Sub;
5449 Bdef :=
5450 Make_Defining_Identifier (Loc,
5451 Build_Selected_Name
5452 (Protnm,
5453 New_External_Name (Chars (Comp_Id), Suffix_Index => -1),
5454 'B'));
5455 Sub :=
5456 Make_Subprogram_Declaration (Loc,
5457 Specification =>
5458 Build_Barrier_Function_Specification (Bdef, Loc));
5460 Insert_After (Current_Node, Sub);
5461 Analyze (Sub);
5462 Set_Protected_Body_Subprogram (Bdef, Bdef);
5463 Set_Barrier_Function (Comp_Id, Bdef);
5464 Set_Scope (Bdef, Scope (Comp_Id));
5465 Current_Node := Sub;
5467 -- Collect pointers to the protected subprogram and the barrier
5468 -- of the current entry, for insertion into Entry_Bodies_Array.
5470 Append (
5471 Make_Aggregate (Loc,
5472 Expressions => New_List (
5473 Make_Attribute_Reference (Loc,
5474 Prefix => New_Reference_To (Bdef, Loc),
5475 Attribute_Name => Name_Unrestricted_Access),
5476 Make_Attribute_Reference (Loc,
5477 Prefix => New_Reference_To (Edef, Loc),
5478 Attribute_Name => Name_Unrestricted_Access))),
5479 Expressions (Entries_Aggr));
5481 end if;
5483 Next (Comp);
5484 end loop;
5486 -- If there are some private entry declarations, expand it as if they
5487 -- were visible entries.
5489 if Present (Private_Declarations (Pdef)) then
5490 Comp := First (Private_Declarations (Pdef));
5492 while Present (Comp) loop
5493 if Nkind (Comp) = N_Entry_Declaration then
5494 E_Count := E_Count + 1;
5495 Comp_Id := Defining_Identifier (Comp);
5496 Set_Privals_Chain (Comp_Id, New_Elmt_List);
5497 Edef :=
5498 Make_Defining_Identifier (Loc,
5499 Build_Selected_Name
5500 (Protnm,
5501 New_External_Name (Chars (Comp_Id), Suffix_Index => -1),
5502 'E'));
5504 Sub :=
5505 Make_Subprogram_Declaration (Loc,
5506 Specification =>
5507 Build_Protected_Entry_Specification (Edef, Comp_Id, Loc));
5509 Insert_After (Current_Node, Sub);
5510 Analyze (Sub);
5512 Set_Protected_Body_Subprogram (
5513 Defining_Identifier (Comp),
5514 Defining_Unit_Name (Specification (Sub)));
5516 Current_Node := Sub;
5518 Bdef :=
5519 Make_Defining_Identifier (Loc,
5520 Build_Selected_Name
5521 (Protnm,
5522 New_External_Name (Chars (Comp_Id), Suffix_Index => -1),
5523 'B'));
5524 Sub :=
5525 Make_Subprogram_Declaration (Loc,
5526 Specification =>
5527 Build_Barrier_Function_Specification (Bdef, Loc));
5529 Insert_After (Current_Node, Sub);
5530 Analyze (Sub);
5531 Set_Protected_Body_Subprogram (Bdef, Bdef);
5532 Set_Barrier_Function (Comp_Id, Bdef);
5533 Set_Scope (Bdef, Scope (Comp_Id));
5534 Current_Node := Sub;
5536 -- Collect pointers to the protected subprogram and the
5537 -- barrier of the current entry, for insertion into
5538 -- Entry_Bodies_Array.
5540 Append (
5541 Make_Aggregate (Loc,
5542 Expressions => New_List (
5543 Make_Attribute_Reference (Loc,
5544 Prefix => New_Reference_To (Bdef, Loc),
5545 Attribute_Name => Name_Unrestricted_Access),
5546 Make_Attribute_Reference (Loc,
5547 Prefix => New_Reference_To (Edef, Loc),
5548 Attribute_Name => Name_Unrestricted_Access))),
5549 Expressions (Entries_Aggr));
5550 end if;
5552 Next (Comp);
5553 end loop;
5554 end if;
5556 -- Emit declaration for Entry_Bodies_Array, now that the addresses of
5557 -- all protected subprograms have been collected.
5559 if Has_Entries (Prottyp) then
5560 Body_Id := Make_Defining_Identifier (Sloc (Prottyp),
5561 New_External_Name (Chars (Prottyp), 'A'));
5563 if Abort_Allowed
5564 or else Restriction_Active (No_Entry_Queue) = False
5565 or else E_Count > 1
5566 then
5567 Body_Arr := Make_Object_Declaration (Loc,
5568 Defining_Identifier => Body_Id,
5569 Aliased_Present => True,
5570 Object_Definition =>
5571 Make_Subtype_Indication (Loc,
5572 Subtype_Mark => New_Reference_To (
5573 RTE (RE_Protected_Entry_Body_Array), Loc),
5574 Constraint =>
5575 Make_Index_Or_Discriminant_Constraint (Loc,
5576 Constraints => New_List (
5577 Make_Range (Loc,
5578 Make_Integer_Literal (Loc, 1),
5579 Make_Integer_Literal (Loc, E_Count))))),
5580 Expression => Entries_Aggr);
5582 else
5583 Body_Arr := Make_Object_Declaration (Loc,
5584 Defining_Identifier => Body_Id,
5585 Aliased_Present => True,
5586 Object_Definition => New_Reference_To (RTE (RE_Entry_Body), Loc),
5587 Expression =>
5588 Make_Aggregate (Loc,
5589 Expressions => New_List (
5590 Make_Attribute_Reference (Loc,
5591 Prefix => New_Reference_To (Bdef, Loc),
5592 Attribute_Name => Name_Unrestricted_Access),
5593 Make_Attribute_Reference (Loc,
5594 Prefix => New_Reference_To (Edef, Loc),
5595 Attribute_Name => Name_Unrestricted_Access))));
5596 end if;
5598 -- A pointer to this array will be placed in the corresponding
5599 -- record by its initialization procedure, so this needs to be
5600 -- analyzed here.
5602 Insert_After (Current_Node, Body_Arr);
5603 Current_Node := Body_Arr;
5604 Analyze (Body_Arr);
5606 Set_Entry_Bodies_Array (Prottyp, Body_Id);
5608 -- Finally, build the function that maps an entry index into the
5609 -- corresponding body. A pointer to this function is placed in each
5610 -- object of the type. Except for a ravenscar-like profile (no abort,
5611 -- no entry queue, 1 entry)
5613 if Abort_Allowed
5614 or else Restriction_Active (No_Entry_Queue) = False
5615 or else E_Count > 1
5616 then
5617 Sub :=
5618 Make_Subprogram_Declaration (Loc,
5619 Specification => Build_Find_Body_Index_Spec (Prottyp));
5620 Insert_After (Current_Node, Sub);
5621 Analyze (Sub);
5622 end if;
5623 end if;
5624 end Expand_N_Protected_Type_Declaration;
5626 --------------------------------
5627 -- Expand_N_Requeue_Statement --
5628 --------------------------------
5630 -- A requeue statement is expanded into one of four GNARLI operations,
5631 -- depending on the source and destination (task or protected object).
5632 -- In addition, code must be generated to jump around the remainder of
5633 -- processing for the original entry and, if the destination is a
5634 -- (different) protected object, to attempt to service it.
5635 -- The following illustrates the various cases:
5637 -- procedure entE
5638 -- (O : System.Address;
5639 -- P : System.Address;
5640 -- E : Protected_Entry_Index)
5641 -- is
5642 -- <discriminant renamings>
5643 -- <private object renamings>
5644 -- type poVP is access poV;
5645 -- _Object : ptVP := ptVP!(O);
5647 -- begin
5648 -- begin
5649 -- <start of statement sequence for entry>
5651 -- -- Requeue from one protected entry body to another protected
5652 -- -- entry.
5654 -- Requeue_Protected_Entry (
5655 -- _object._object'Access,
5656 -- new._object'Access,
5657 -- E,
5658 -- Abort_Present);
5659 -- return;
5661 -- <some more of the statement sequence for entry>
5663 -- -- Requeue from an entry body to a task entry
5665 -- Requeue_Protected_To_Task_Entry (
5666 -- New._task_id,
5667 -- E,
5668 -- Abort_Present);
5669 -- return;
5671 -- <rest of statement sequence for entry>
5672 -- Complete_Entry_Body (_Object._Object);
5674 -- exception
5675 -- when all others =>
5676 -- Exceptional_Complete_Entry_Body (
5677 -- _Object._Object, Get_GNAT_Exception);
5678 -- end;
5679 -- end entE;
5681 -- Requeue of a task entry call to a task entry
5683 -- Accept_Call (E, Ann);
5684 -- <start of statement sequence for accept statement>
5685 -- Requeue_Task_Entry (New._task_id, E, Abort_Present);
5686 -- goto Lnn;
5687 -- <rest of statement sequence for accept statement>
5688 -- <<Lnn>>
5689 -- Complete_Rendezvous;
5691 -- exception
5692 -- when all others =>
5693 -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
5695 -- Requeue of a task entry call to a protected entry
5697 -- Accept_Call (E, Ann);
5698 -- <start of statement sequence for accept statement>
5699 -- Requeue_Task_To_Protected_Entry (
5700 -- new._object'Access,
5701 -- E,
5702 -- Abort_Present);
5703 -- newS (new, Pnn);
5704 -- goto Lnn;
5705 -- <rest of statement sequence for accept statement>
5706 -- <<Lnn>>
5707 -- Complete_Rendezvous;
5709 -- exception
5710 -- when all others =>
5711 -- Exceptional_Complete_Rendezvous (Get_GNAT_Exception);
5713 -- Further details on these expansions can be found in
5714 -- Expand_N_Protected_Body and Expand_N_Accept_Statement.
5716 procedure Expand_N_Requeue_Statement (N : Node_Id) is
5717 Loc : constant Source_Ptr := Sloc (N);
5718 Acc_Stat : Node_Id;
5719 Concval : Node_Id;
5720 Ename : Node_Id;
5721 Index : Node_Id;
5722 Conctyp : Entity_Id;
5723 Oldtyp : Entity_Id;
5724 Lab_Node : Node_Id;
5725 Rcall : Node_Id;
5726 Abortable : Node_Id;
5727 Skip_Stat : Node_Id;
5728 Self_Param : Node_Id;
5729 New_Param : Node_Id;
5730 Params : List_Id;
5731 RTS_Call : Entity_Id;
5733 begin
5734 Abortable :=
5735 New_Occurrence_Of (Boolean_Literals (Abort_Present (N)), Loc);
5737 -- Set up the target object
5739 Extract_Entry (N, Concval, Ename, Index);
5740 Conctyp := Etype (Concval);
5741 New_Param := Concurrent_Ref (Concval);
5743 -- The target entry index and abortable flag are the same for all cases
5745 Params := New_List (
5746 Entry_Index_Expression (Loc, Entity (Ename), Index, Conctyp),
5747 Abortable);
5749 -- Determine proper GNARLI call and required additional parameters
5750 -- Loop to find nearest enclosing task type or protected type
5752 Oldtyp := Current_Scope;
5753 loop
5754 if Is_Task_Type (Oldtyp) then
5755 if Is_Task_Type (Conctyp) then
5756 RTS_Call := RTE (RE_Requeue_Task_Entry);
5758 else
5759 pragma Assert (Is_Protected_Type (Conctyp));
5760 RTS_Call := RTE (RE_Requeue_Task_To_Protected_Entry);
5761 New_Param :=
5762 Make_Attribute_Reference (Loc,
5763 Prefix => New_Param,
5764 Attribute_Name => Name_Unchecked_Access);
5765 end if;
5767 Prepend (New_Param, Params);
5768 exit;
5770 elsif Is_Protected_Type (Oldtyp) then
5771 Self_Param :=
5772 Make_Attribute_Reference (Loc,
5773 Prefix => Concurrent_Ref (New_Occurrence_Of (Oldtyp, Loc)),
5774 Attribute_Name => Name_Unchecked_Access);
5776 if Is_Task_Type (Conctyp) then
5777 RTS_Call := RTE (RE_Requeue_Protected_To_Task_Entry);
5779 else
5780 pragma Assert (Is_Protected_Type (Conctyp));
5781 RTS_Call := RTE (RE_Requeue_Protected_Entry);
5782 New_Param :=
5783 Make_Attribute_Reference (Loc,
5784 Prefix => New_Param,
5785 Attribute_Name => Name_Unchecked_Access);
5786 end if;
5788 Prepend (New_Param, Params);
5789 Prepend (Self_Param, Params);
5790 exit;
5792 -- If neither task type or protected type, must be in some
5793 -- inner enclosing block, so move on out
5795 else
5796 Oldtyp := Scope (Oldtyp);
5797 end if;
5798 end loop;
5800 -- Create the GNARLI call
5802 Rcall := Make_Procedure_Call_Statement (Loc,
5803 Name =>
5804 New_Occurrence_Of (RTS_Call, Loc),
5805 Parameter_Associations => Params);
5807 Rewrite (N, Rcall);
5808 Analyze (N);
5810 if Is_Protected_Type (Oldtyp) then
5812 -- Build the return statement to skip the rest of the entry body
5814 Skip_Stat := Make_Return_Statement (Loc);
5816 else
5817 -- If the requeue is within a task, find the end label of the
5818 -- enclosing accept statement.
5820 Acc_Stat := Parent (N);
5821 while Nkind (Acc_Stat) /= N_Accept_Statement loop
5822 Acc_Stat := Parent (Acc_Stat);
5823 end loop;
5825 -- The last statement is the second label, used for completing the
5826 -- rendezvous the usual way.
5827 -- The label we are looking for is right before it.
5829 Lab_Node :=
5830 Prev (Last (Statements (Handled_Statement_Sequence (Acc_Stat))));
5832 pragma Assert (Nkind (Lab_Node) = N_Label);
5834 -- Build the goto statement to skip the rest of the accept
5835 -- statement.
5837 Skip_Stat :=
5838 Make_Goto_Statement (Loc,
5839 Name => New_Occurrence_Of (Entity (Identifier (Lab_Node)), Loc));
5840 end if;
5842 Set_Analyzed (Skip_Stat);
5844 Insert_After (N, Skip_Stat);
5845 end Expand_N_Requeue_Statement;
5847 -------------------------------
5848 -- Expand_N_Selective_Accept --
5849 -------------------------------
5851 procedure Expand_N_Selective_Accept (N : Node_Id) is
5852 Loc : constant Source_Ptr := Sloc (N);
5853 Alts : constant List_Id := Select_Alternatives (N);
5855 -- Note: in the below declarations a lot of new lists are allocated
5856 -- unconditionally which may well not end up being used. That's
5857 -- not a good idea since it wastes space gratuitously ???
5859 Accept_Case : List_Id;
5860 Accept_List : constant List_Id := New_List;
5862 Alt : Node_Id;
5863 Alt_List : constant List_Id := New_List;
5864 Alt_Stats : List_Id;
5865 Ann : Entity_Id := Empty;
5867 Block : Node_Id;
5868 Check_Guard : Boolean := True;
5870 Decls : constant List_Id := New_List;
5871 Stats : constant List_Id := New_List;
5872 Body_List : constant List_Id := New_List;
5873 Trailing_List : constant List_Id := New_List;
5875 Choices : List_Id;
5876 Else_Present : Boolean := False;
5877 Terminate_Alt : Node_Id := Empty;
5878 Select_Mode : Node_Id;
5880 Delay_Case : List_Id;
5881 Delay_Count : Integer := 0;
5882 Delay_Val : Entity_Id;
5883 Delay_Index : Entity_Id;
5884 Delay_Min : Entity_Id;
5885 Delay_Num : Int := 1;
5886 Delay_Alt_List : List_Id := New_List;
5887 Delay_List : constant List_Id := New_List;
5888 D : Entity_Id;
5889 M : Entity_Id;
5891 First_Delay : Boolean := True;
5892 Guard_Open : Entity_Id;
5894 End_Lab : Node_Id;
5895 Index : Int := 1;
5896 Lab : Node_Id;
5897 Num_Alts : Int;
5898 Num_Accept : Nat := 0;
5899 Proc : Node_Id;
5900 Q : Node_Id;
5901 Time_Type : Entity_Id;
5902 X : Node_Id;
5903 Select_Call : Node_Id;
5905 Qnam : constant Entity_Id :=
5906 Make_Defining_Identifier (Loc, New_External_Name ('S', 0));
5908 Xnam : constant Entity_Id :=
5909 Make_Defining_Identifier (Loc, New_External_Name ('J', 1));
5911 -----------------------
5912 -- Local subprograms --
5913 -----------------------
5915 function Accept_Or_Raise return List_Id;
5916 -- For the rare case where delay alternatives all have guards, and
5917 -- all of them are closed, it is still possible that there were open
5918 -- accept alternatives with no callers. We must reexamine the
5919 -- Accept_List, and execute a selective wait with no else if some
5920 -- accept is open. If none, we raise program_error.
5922 procedure Add_Accept (Alt : Node_Id);
5923 -- Process a single accept statement in a select alternative. Build
5924 -- procedure for body of accept, and add entry to dispatch table with
5925 -- expression for guard, in preparation for call to run time select.
5927 function Make_And_Declare_Label (Num : Int) return Node_Id;
5928 -- Manufacture a label using Num as a serial number and declare it.
5929 -- The declaration is appended to Decls. The label marks the trailing
5930 -- statements of an accept or delay alternative.
5932 function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id;
5933 -- Build call to Selective_Wait runtime routine
5935 procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int);
5936 -- Add code to compare value of delay with previous values, and
5937 -- generate case entry for trailing statements.
5939 procedure Process_Accept_Alternative
5940 (Alt : Node_Id;
5941 Index : Int;
5942 Proc : Node_Id);
5943 -- Add code to call corresponding procedure, and branch to
5944 -- trailing statements, if any.
5946 ---------------------
5947 -- Accept_Or_Raise --
5948 ---------------------
5950 function Accept_Or_Raise return List_Id is
5951 Cond : Node_Id;
5952 Stats : List_Id;
5953 J : constant Entity_Id := Make_Defining_Identifier (Loc,
5954 New_Internal_Name ('J'));
5956 begin
5957 -- We generate the following:
5959 -- for J in q'range loop
5960 -- if q(J).S /=null_task_entry then
5961 -- selective_wait (simple_mode,...);
5962 -- done := True;
5963 -- exit;
5964 -- end if;
5965 -- end loop;
5967 -- if no rendez_vous then
5968 -- raise program_error;
5969 -- end if;
5971 -- Note that the code needs to know that the selector name
5972 -- in an Accept_Alternative is named S.
5974 Cond := Make_Op_Ne (Loc,
5975 Left_Opnd =>
5976 Make_Selected_Component (Loc,
5977 Prefix => Make_Indexed_Component (Loc,
5978 Prefix => New_Reference_To (Qnam, Loc),
5979 Expressions => New_List (New_Reference_To (J, Loc))),
5980 Selector_Name => Make_Identifier (Loc, Name_S)),
5981 Right_Opnd =>
5982 New_Reference_To (RTE (RE_Null_Task_Entry), Loc));
5984 Stats := New_List (
5985 Make_Implicit_Loop_Statement (N,
5986 Identifier => Empty,
5987 Iteration_Scheme =>
5988 Make_Iteration_Scheme (Loc,
5989 Loop_Parameter_Specification =>
5990 Make_Loop_Parameter_Specification (Loc,
5991 Defining_Identifier => J,
5992 Discrete_Subtype_Definition =>
5993 Make_Attribute_Reference (Loc,
5994 Prefix => New_Reference_To (Qnam, Loc),
5995 Attribute_Name => Name_Range,
5996 Expressions => New_List (
5997 Make_Integer_Literal (Loc, 1))))),
5999 Statements => New_List (
6000 Make_Implicit_If_Statement (N,
6001 Condition => Cond,
6002 Then_Statements => New_List (
6003 Make_Select_Call (
6004 New_Reference_To (RTE (RE_Simple_Mode), Loc)),
6005 Make_Exit_Statement (Loc))))));
6007 Append_To (Stats,
6008 Make_Raise_Program_Error (Loc,
6009 Condition => Make_Op_Eq (Loc,
6010 Left_Opnd => New_Reference_To (Xnam, Loc),
6011 Right_Opnd =>
6012 New_Reference_To (RTE (RE_No_Rendezvous), Loc)),
6013 Reason => PE_All_Guards_Closed));
6015 return Stats;
6016 end Accept_Or_Raise;
6018 ----------------
6019 -- Add_Accept --
6020 ----------------
6022 procedure Add_Accept (Alt : Node_Id) is
6023 Acc_Stm : constant Node_Id := Accept_Statement (Alt);
6024 Ename : constant Node_Id := Entry_Direct_Name (Acc_Stm);
6025 Eent : constant Entity_Id := Entity (Ename);
6026 Index : constant Node_Id := Entry_Index (Acc_Stm);
6027 Null_Body : Node_Id;
6028 Proc_Body : Node_Id;
6029 PB_Ent : Entity_Id;
6030 Expr : Node_Id;
6031 Call : Node_Id;
6033 begin
6034 if No (Ann) then
6035 Ann := Node (Last_Elmt (Accept_Address (Eent)));
6036 end if;
6038 if Present (Condition (Alt)) then
6039 Expr :=
6040 Make_Conditional_Expression (Loc, New_List (
6041 Condition (Alt),
6042 Entry_Index_Expression (Loc, Eent, Index, Scope (Eent)),
6043 New_Reference_To (RTE (RE_Null_Task_Entry), Loc)));
6044 else
6045 Expr :=
6046 Entry_Index_Expression
6047 (Loc, Eent, Index, Scope (Eent));
6048 end if;
6050 if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then
6051 Null_Body := New_Reference_To (Standard_False, Loc);
6053 if Abort_Allowed then
6054 Call := Make_Procedure_Call_Statement (Loc,
6055 Name => New_Reference_To (RTE (RE_Abort_Undefer), Loc));
6056 Insert_Before (First (Statements (Handled_Statement_Sequence (
6057 Accept_Statement (Alt)))), Call);
6058 Analyze (Call);
6059 end if;
6061 PB_Ent :=
6062 Make_Defining_Identifier (Sloc (Ename),
6063 New_External_Name (Chars (Ename), 'A', Num_Accept));
6065 Set_Needs_Debug_Info (PB_Ent, Comes_From_Source (Alt));
6067 Proc_Body :=
6068 Make_Subprogram_Body (Loc,
6069 Specification =>
6070 Make_Procedure_Specification (Loc,
6071 Defining_Unit_Name => PB_Ent),
6072 Declarations => Declarations (Acc_Stm),
6073 Handled_Statement_Sequence =>
6074 Build_Accept_Body (Accept_Statement (Alt)));
6076 -- During the analysis of the body of the accept statement, any
6077 -- zero cost exception handler records were collected in the
6078 -- Accept_Handler_Records field of the N_Accept_Alternative
6079 -- node. This is where we move them to where they belong,
6080 -- namely the newly created procedure.
6082 Set_Handler_Records (PB_Ent, Accept_Handler_Records (Alt));
6083 Append (Proc_Body, Body_List);
6085 else
6086 Null_Body := New_Reference_To (Standard_True, Loc);
6088 -- if accept statement has declarations, insert above, given
6089 -- that we are not creating a body for the accept.
6091 if Present (Declarations (Acc_Stm)) then
6092 Insert_Actions (N, Declarations (Acc_Stm));
6093 end if;
6094 end if;
6096 Append_To (Accept_List,
6097 Make_Aggregate (Loc, Expressions => New_List (Null_Body, Expr)));
6099 Num_Accept := Num_Accept + 1;
6100 end Add_Accept;
6102 ----------------------------
6103 -- Make_And_Declare_Label --
6104 ----------------------------
6106 function Make_And_Declare_Label (Num : Int) return Node_Id is
6107 Lab_Id : Node_Id;
6109 begin
6110 Lab_Id := Make_Identifier (Loc, New_External_Name ('L', Num));
6111 Lab :=
6112 Make_Label (Loc, Lab_Id);
6114 Append_To (Decls,
6115 Make_Implicit_Label_Declaration (Loc,
6116 Defining_Identifier =>
6117 Make_Defining_Identifier (Loc, Chars (Lab_Id)),
6118 Label_Construct => Lab));
6120 return Lab;
6121 end Make_And_Declare_Label;
6123 ----------------------
6124 -- Make_Select_Call --
6125 ----------------------
6127 function Make_Select_Call (Select_Mode : Entity_Id) return Node_Id is
6128 Params : constant List_Id := New_List;
6130 begin
6131 Append (
6132 Make_Attribute_Reference (Loc,
6133 Prefix => New_Reference_To (Qnam, Loc),
6134 Attribute_Name => Name_Unchecked_Access),
6135 Params);
6136 Append (Select_Mode, Params);
6137 Append (New_Reference_To (Ann, Loc), Params);
6138 Append (New_Reference_To (Xnam, Loc), Params);
6140 return
6141 Make_Procedure_Call_Statement (Loc,
6142 Name => New_Reference_To (RTE (RE_Selective_Wait), Loc),
6143 Parameter_Associations => Params);
6144 end Make_Select_Call;
6146 --------------------------------
6147 -- Process_Accept_Alternative --
6148 --------------------------------
6150 procedure Process_Accept_Alternative
6151 (Alt : Node_Id;
6152 Index : Int;
6153 Proc : Node_Id)
6155 Choices : List_Id := No_List;
6156 Alt_Stats : List_Id;
6158 begin
6159 Adjust_Condition (Condition (Alt));
6160 Alt_Stats := No_List;
6162 if Present (Handled_Statement_Sequence (Accept_Statement (Alt))) then
6163 Choices := New_List (
6164 Make_Integer_Literal (Loc, Index));
6166 Alt_Stats := New_List (
6167 Make_Procedure_Call_Statement (Loc,
6168 Name => New_Reference_To (
6169 Defining_Unit_Name (Specification (Proc)), Loc)));
6170 end if;
6172 if Statements (Alt) /= Empty_List then
6174 if No (Alt_Stats) then
6176 -- Accept with no body, followed by trailing statements
6178 Choices := New_List (
6179 Make_Integer_Literal (Loc, Index));
6181 Alt_Stats := New_List;
6182 end if;
6184 -- After the call, if any, branch to to trailing statements.
6185 -- We create a label for each, as well as the corresponding
6186 -- label declaration.
6188 Lab := Make_And_Declare_Label (Index);
6189 Append_To (Alt_Stats,
6190 Make_Goto_Statement (Loc,
6191 Name => New_Copy (Identifier (Lab))));
6193 Append (Lab, Trailing_List);
6194 Append_List (Statements (Alt), Trailing_List);
6195 Append_To (Trailing_List,
6196 Make_Goto_Statement (Loc,
6197 Name => New_Copy (Identifier (End_Lab))));
6198 end if;
6200 if Present (Alt_Stats) then
6202 -- Procedure call. and/or trailing statements
6204 Append_To (Alt_List,
6205 Make_Case_Statement_Alternative (Loc,
6206 Discrete_Choices => Choices,
6207 Statements => Alt_Stats));
6208 end if;
6209 end Process_Accept_Alternative;
6211 -------------------------------
6212 -- Process_Delay_Alternative --
6213 -------------------------------
6215 procedure Process_Delay_Alternative (Alt : Node_Id; Index : Int) is
6216 Choices : List_Id;
6217 Cond : Node_Id;
6218 Delay_Alt : List_Id;
6220 begin
6221 -- Deal with C/Fortran boolean as delay condition
6223 Adjust_Condition (Condition (Alt));
6225 -- Determine the smallest specified delay
6227 -- for each delay alternative generate:
6229 -- if guard-expression then
6230 -- Delay_Val := delay-expression;
6231 -- Guard_Open := True;
6232 -- if Delay_Val < Delay_Min then
6233 -- Delay_Min := Delay_Val;
6234 -- Delay_Index := Index;
6235 -- end if;
6236 -- end if;
6238 -- The enclosing if-statement is omitted if there is no guard
6240 if Delay_Count = 1
6241 or else First_Delay
6242 then
6243 First_Delay := False;
6245 Delay_Alt := New_List (
6246 Make_Assignment_Statement (Loc,
6247 Name => New_Reference_To (Delay_Min, Loc),
6248 Expression => Expression (Delay_Statement (Alt))));
6250 if Delay_Count > 1 then
6251 Append_To (Delay_Alt,
6252 Make_Assignment_Statement (Loc,
6253 Name => New_Reference_To (Delay_Index, Loc),
6254 Expression => Make_Integer_Literal (Loc, Index)));
6255 end if;
6257 else
6258 Delay_Alt := New_List (
6259 Make_Assignment_Statement (Loc,
6260 Name => New_Reference_To (Delay_Val, Loc),
6261 Expression => Expression (Delay_Statement (Alt))));
6263 if Time_Type = Standard_Duration then
6264 Cond :=
6265 Make_Op_Lt (Loc,
6266 Left_Opnd => New_Reference_To (Delay_Val, Loc),
6267 Right_Opnd => New_Reference_To (Delay_Min, Loc));
6269 else
6270 -- The scope of the time type must define a comparison
6271 -- operator. The scope itself may not be visible, so we
6272 -- construct a node with entity information to insure that
6273 -- semantic analysis can find the proper operator.
6275 Cond :=
6276 Make_Function_Call (Loc,
6277 Name => Make_Selected_Component (Loc,
6278 Prefix => New_Reference_To (Scope (Time_Type), Loc),
6279 Selector_Name =>
6280 Make_Operator_Symbol (Loc,
6281 Chars => Name_Op_Lt,
6282 Strval => No_String)),
6283 Parameter_Associations =>
6284 New_List (
6285 New_Reference_To (Delay_Val, Loc),
6286 New_Reference_To (Delay_Min, Loc)));
6288 Set_Entity (Prefix (Name (Cond)), Scope (Time_Type));
6289 end if;
6291 Append_To (Delay_Alt,
6292 Make_Implicit_If_Statement (N,
6293 Condition => Cond,
6294 Then_Statements => New_List (
6295 Make_Assignment_Statement (Loc,
6296 Name => New_Reference_To (Delay_Min, Loc),
6297 Expression => New_Reference_To (Delay_Val, Loc)),
6299 Make_Assignment_Statement (Loc,
6300 Name => New_Reference_To (Delay_Index, Loc),
6301 Expression => Make_Integer_Literal (Loc, Index)))));
6302 end if;
6304 if Check_Guard then
6305 Append_To (Delay_Alt,
6306 Make_Assignment_Statement (Loc,
6307 Name => New_Reference_To (Guard_Open, Loc),
6308 Expression => New_Reference_To (Standard_True, Loc)));
6309 end if;
6311 if Present (Condition (Alt)) then
6312 Delay_Alt := New_List (
6313 Make_Implicit_If_Statement (N,
6314 Condition => Condition (Alt),
6315 Then_Statements => Delay_Alt));
6316 end if;
6318 Append_List (Delay_Alt, Delay_List);
6320 -- If the delay alternative has a statement part, add a
6321 -- choice to the case statements for delays.
6323 if Present (Statements (Alt)) then
6325 if Delay_Count = 1 then
6326 Append_List (Statements (Alt), Delay_Alt_List);
6328 else
6329 Choices := New_List (
6330 Make_Integer_Literal (Loc, Index));
6332 Append_To (Delay_Alt_List,
6333 Make_Case_Statement_Alternative (Loc,
6334 Discrete_Choices => Choices,
6335 Statements => Statements (Alt)));
6336 end if;
6338 elsif Delay_Count = 1 then
6340 -- If the single delay has no trailing statements, add a branch
6341 -- to the exit label to the selective wait.
6343 Delay_Alt_List := New_List (
6344 Make_Goto_Statement (Loc,
6345 Name => New_Copy (Identifier (End_Lab))));
6347 end if;
6348 end Process_Delay_Alternative;
6350 -- Start of processing for Expand_N_Selective_Accept
6352 begin
6353 -- First insert some declarations before the select. The first is:
6355 -- Ann : Address
6357 -- This variable holds the parameters passed to the accept body. This
6358 -- declaration has already been inserted by the time we get here by
6359 -- a call to Expand_Accept_Declarations made from the semantics when
6360 -- processing the first accept statement contained in the select. We
6361 -- can find this entity as Accept_Address (E), where E is any of the
6362 -- entries references by contained accept statements.
6364 -- The first step is to scan the list of Selective_Accept_Statements
6365 -- to find this entity, and also count the number of accepts, and
6366 -- determine if terminated, delay or else is present:
6368 Num_Alts := 0;
6370 Alt := First (Alts);
6371 while Present (Alt) loop
6373 if Nkind (Alt) = N_Accept_Alternative then
6374 Add_Accept (Alt);
6376 elsif Nkind (Alt) = N_Delay_Alternative then
6377 Delay_Count := Delay_Count + 1;
6379 -- If the delays are relative delays, the delay expressions have
6380 -- type Standard_Duration. Otherwise they must have some time type
6381 -- recognized by GNAT.
6383 if Nkind (Delay_Statement (Alt)) = N_Delay_Relative_Statement then
6384 Time_Type := Standard_Duration;
6385 else
6386 Time_Type := Etype (Expression (Delay_Statement (Alt)));
6388 if Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time)
6389 or else Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time)
6390 then
6391 null;
6392 else
6393 Error_Msg_NE (
6394 "& is not a time type ('R'M 9.6(6))",
6395 Expression (Delay_Statement (Alt)), Time_Type);
6396 Time_Type := Standard_Duration;
6397 Set_Etype (Expression (Delay_Statement (Alt)), Any_Type);
6398 end if;
6399 end if;
6401 if No (Condition (Alt)) then
6403 -- This guard will always be open
6405 Check_Guard := False;
6406 end if;
6408 elsif Nkind (Alt) = N_Terminate_Alternative then
6409 Adjust_Condition (Condition (Alt));
6410 Terminate_Alt := Alt;
6411 end if;
6413 Num_Alts := Num_Alts + 1;
6414 Next (Alt);
6415 end loop;
6417 Else_Present := Present (Else_Statements (N));
6419 -- At the same time (see procedure Add_Accept) we build the accept list:
6421 -- Qnn : Accept_List (1 .. num-select) := (
6422 -- (null-body, entry-index),
6423 -- (null-body, entry-index),
6424 -- ..
6425 -- (null_body, entry-index));
6427 -- In the above declaration, null-body is True if the corresponding
6428 -- accept has no body, and false otherwise. The entry is either the
6429 -- entry index expression if there is no guard, or if a guard is
6430 -- present, then a conditional expression of the form:
6432 -- (if guard then entry-index else Null_Task_Entry)
6434 -- If a guard is statically known to be false, the entry can simply
6435 -- be omitted from the accept list.
6437 Q :=
6438 Make_Object_Declaration (Loc,
6439 Defining_Identifier => Qnam,
6440 Object_Definition =>
6441 New_Reference_To (RTE (RE_Accept_List), Loc),
6442 Aliased_Present => True,
6444 Expression =>
6445 Make_Qualified_Expression (Loc,
6446 Subtype_Mark =>
6447 New_Reference_To (RTE (RE_Accept_List), Loc),
6448 Expression =>
6449 Make_Aggregate (Loc, Expressions => Accept_List)));
6451 Append (Q, Decls);
6453 -- Then we declare the variable that holds the index for the accept
6454 -- that will be selected for service:
6456 -- Xnn : Select_Index;
6458 X :=
6459 Make_Object_Declaration (Loc,
6460 Defining_Identifier => Xnam,
6461 Object_Definition =>
6462 New_Reference_To (RTE (RE_Select_Index), Loc),
6463 Expression =>
6464 New_Reference_To (RTE (RE_No_Rendezvous), Loc));
6466 Append (X, Decls);
6468 -- After this follow procedure declarations for each accept body
6470 -- procedure Pnn is
6471 -- begin
6472 -- ...
6473 -- end;
6475 -- where the ... are statements from the corresponding procedure body.
6476 -- No parameters are involved, since the parameters are passed via Ann
6477 -- and the parameter references have already been expanded to be direct
6478 -- references to Ann (see Exp_Ch2.Expand_Entry_Parameter). Furthermore,
6479 -- any embedded tasking statements (which would normally be illegal in
6480 -- procedures, have been converted to calls to the tasking runtime so
6481 -- there is no problem in putting them into procedures.
6483 -- The original accept statement has been expanded into a block in
6484 -- the same fashion as for simple accepts (see Build_Accept_Body).
6486 -- Note: we don't really need to build these procedures for the case
6487 -- where no delay statement is present, but it is just as easy to
6488 -- build them unconditionally, and not significantly inefficient,
6489 -- since if they are short they will be inlined anyway.
6491 -- The procedure declarations have been assembled in Body_List
6493 -- If delays are present, we must compute the required delay.
6494 -- We first generate the declarations:
6496 -- Delay_Index : Boolean := 0;
6497 -- Delay_Min : Some_Time_Type.Time;
6498 -- Delay_Val : Some_Time_Type.Time;
6500 -- Delay_Index will be set to the index of the minimum delay, i.e. the
6501 -- active delay that is actually chosen as the basis for the possible
6502 -- delay if an immediate rendez-vous is not possible.
6504 -- In the most common case there is a single delay statement, and this
6505 -- is handled specially.
6507 if Delay_Count > 0 then
6509 -- Generate the required declarations
6511 Delay_Val :=
6512 Make_Defining_Identifier (Loc, New_External_Name ('D', 1));
6513 Delay_Index :=
6514 Make_Defining_Identifier (Loc, New_External_Name ('D', 2));
6515 Delay_Min :=
6516 Make_Defining_Identifier (Loc, New_External_Name ('D', 3));
6518 Append_To (Decls,
6519 Make_Object_Declaration (Loc,
6520 Defining_Identifier => Delay_Val,
6521 Object_Definition => New_Reference_To (Time_Type, Loc)));
6523 Append_To (Decls,
6524 Make_Object_Declaration (Loc,
6525 Defining_Identifier => Delay_Index,
6526 Object_Definition => New_Reference_To (Standard_Integer, Loc),
6527 Expression => Make_Integer_Literal (Loc, 0)));
6529 Append_To (Decls,
6530 Make_Object_Declaration (Loc,
6531 Defining_Identifier => Delay_Min,
6532 Object_Definition => New_Reference_To (Time_Type, Loc),
6533 Expression =>
6534 Unchecked_Convert_To (Time_Type,
6535 Make_Attribute_Reference (Loc,
6536 Prefix =>
6537 New_Occurrence_Of (Underlying_Type (Time_Type), Loc),
6538 Attribute_Name => Name_Last))));
6540 -- Create Duration and Delay_Mode objects used for passing a delay
6541 -- value to RTS
6543 D := Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
6544 M := Make_Defining_Identifier (Loc, New_Internal_Name ('M'));
6546 declare
6547 Discr : Entity_Id;
6549 begin
6550 -- Note that these values are defined in s-osprim.ads and must
6551 -- be kept in sync:
6553 -- Relative : constant := 0;
6554 -- Absolute_Calendar : constant := 1;
6555 -- Absolute_RT : constant := 2;
6557 if Time_Type = Standard_Duration then
6558 Discr := Make_Integer_Literal (Loc, 0);
6560 elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then
6561 Discr := Make_Integer_Literal (Loc, 1);
6563 else
6564 pragma Assert
6565 (Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time));
6566 Discr := Make_Integer_Literal (Loc, 2);
6567 end if;
6569 Append_To (Decls,
6570 Make_Object_Declaration (Loc,
6571 Defining_Identifier => D,
6572 Object_Definition =>
6573 New_Reference_To (Standard_Duration, Loc)));
6575 Append_To (Decls,
6576 Make_Object_Declaration (Loc,
6577 Defining_Identifier => M,
6578 Object_Definition =>
6579 New_Reference_To (Standard_Integer, Loc),
6580 Expression => Discr));
6581 end;
6583 if Check_Guard then
6584 Guard_Open :=
6585 Make_Defining_Identifier (Loc, New_External_Name ('G', 1));
6587 Append_To (Decls,
6588 Make_Object_Declaration (Loc,
6589 Defining_Identifier => Guard_Open,
6590 Object_Definition => New_Reference_To (Standard_Boolean, Loc),
6591 Expression => New_Reference_To (Standard_False, Loc)));
6592 end if;
6594 -- Delay_Count is zero, don't need M and D set (suppress warning)
6596 else
6597 M := Empty;
6598 D := Empty;
6599 end if;
6601 if Present (Terminate_Alt) then
6603 -- If the terminate alternative guard is False, use
6604 -- Simple_Mode; otherwise use Terminate_Mode.
6606 if Present (Condition (Terminate_Alt)) then
6607 Select_Mode := Make_Conditional_Expression (Loc,
6608 New_List (Condition (Terminate_Alt),
6609 New_Reference_To (RTE (RE_Terminate_Mode), Loc),
6610 New_Reference_To (RTE (RE_Simple_Mode), Loc)));
6611 else
6612 Select_Mode := New_Reference_To (RTE (RE_Terminate_Mode), Loc);
6613 end if;
6615 elsif Else_Present or Delay_Count > 0 then
6616 Select_Mode := New_Reference_To (RTE (RE_Else_Mode), Loc);
6618 else
6619 Select_Mode := New_Reference_To (RTE (RE_Simple_Mode), Loc);
6620 end if;
6622 Select_Call := Make_Select_Call (Select_Mode);
6623 Append (Select_Call, Stats);
6625 -- Now generate code to act on the result. There is an entry
6626 -- in this case for each accept statement with a non-null body,
6627 -- followed by a branch to the statements that follow the Accept.
6628 -- In the absence of delay alternatives, we generate:
6630 -- case X is
6631 -- when No_Rendezvous => -- omitted if simple mode
6632 -- goto Lab0;
6634 -- when 1 =>
6635 -- P1n;
6636 -- goto Lab1;
6638 -- when 2 =>
6639 -- P2n;
6640 -- goto Lab2;
6642 -- when others =>
6643 -- goto Exit;
6644 -- end case;
6646 -- Lab0: Else_Statements;
6647 -- goto exit;
6649 -- Lab1: Trailing_Statements1;
6650 -- goto Exit;
6652 -- Lab2: Trailing_Statements2;
6653 -- goto Exit;
6654 -- ...
6655 -- Exit:
6657 -- Generate label for common exit
6659 End_Lab := Make_And_Declare_Label (Num_Alts + 1);
6661 -- First entry is the default case, when no rendezvous is possible
6663 Choices := New_List (New_Reference_To (RTE (RE_No_Rendezvous), Loc));
6665 if Else_Present then
6667 -- If no rendezvous is possible, the else part is executed
6669 Lab := Make_And_Declare_Label (0);
6670 Alt_Stats := New_List (
6671 Make_Goto_Statement (Loc,
6672 Name => New_Copy (Identifier (Lab))));
6674 Append (Lab, Trailing_List);
6675 Append_List (Else_Statements (N), Trailing_List);
6676 Append_To (Trailing_List,
6677 Make_Goto_Statement (Loc,
6678 Name => New_Copy (Identifier (End_Lab))));
6679 else
6680 Alt_Stats := New_List (
6681 Make_Goto_Statement (Loc,
6682 Name => New_Copy (Identifier (End_Lab))));
6683 end if;
6685 Append_To (Alt_List,
6686 Make_Case_Statement_Alternative (Loc,
6687 Discrete_Choices => Choices,
6688 Statements => Alt_Stats));
6690 -- We make use of the fact that Accept_Index is an integer type,
6691 -- and generate successive literals for entries for each accept.
6692 -- Only those for which there is a body or trailing statements are
6693 -- given a case entry.
6695 Alt := First (Select_Alternatives (N));
6696 Proc := First (Body_List);
6698 while Present (Alt) loop
6700 if Nkind (Alt) = N_Accept_Alternative then
6701 Process_Accept_Alternative (Alt, Index, Proc);
6702 Index := Index + 1;
6704 if Present
6705 (Handled_Statement_Sequence (Accept_Statement (Alt)))
6706 then
6707 Next (Proc);
6708 end if;
6710 elsif Nkind (Alt) = N_Delay_Alternative then
6711 Process_Delay_Alternative (Alt, Delay_Num);
6712 Delay_Num := Delay_Num + 1;
6713 end if;
6715 Next (Alt);
6716 end loop;
6718 -- An others choice is always added to the main case, as well
6719 -- as the delay case (to satisfy the compiler).
6721 Append_To (Alt_List,
6722 Make_Case_Statement_Alternative (Loc,
6723 Discrete_Choices =>
6724 New_List (Make_Others_Choice (Loc)),
6725 Statements =>
6726 New_List (Make_Goto_Statement (Loc,
6727 Name => New_Copy (Identifier (End_Lab))))));
6729 Accept_Case := New_List (
6730 Make_Case_Statement (Loc,
6731 Expression => New_Reference_To (Xnam, Loc),
6732 Alternatives => Alt_List));
6734 Append_List (Trailing_List, Accept_Case);
6735 Append (End_Lab, Accept_Case);
6736 Append_List (Body_List, Decls);
6738 -- Construct case statement for trailing statements of delay
6739 -- alternatives, if there are several of them.
6741 if Delay_Count > 1 then
6742 Append_To (Delay_Alt_List,
6743 Make_Case_Statement_Alternative (Loc,
6744 Discrete_Choices =>
6745 New_List (Make_Others_Choice (Loc)),
6746 Statements =>
6747 New_List (Make_Null_Statement (Loc))));
6749 Delay_Case := New_List (
6750 Make_Case_Statement (Loc,
6751 Expression => New_Reference_To (Delay_Index, Loc),
6752 Alternatives => Delay_Alt_List));
6753 else
6754 Delay_Case := Delay_Alt_List;
6755 end if;
6757 -- If there are no delay alternatives, we append the case statement
6758 -- to the statement list.
6760 if Delay_Count = 0 then
6761 Append_List (Accept_Case, Stats);
6763 -- Delay alternatives present
6765 else
6766 -- If delay alternatives are present we generate:
6768 -- find minimum delay.
6769 -- DX := minimum delay;
6770 -- M := <delay mode>;
6771 -- Timed_Selective_Wait (Q'Unchecked_Access, Delay_Mode, P,
6772 -- DX, MX, X);
6774 -- if X = No_Rendezvous then
6775 -- case statement for delay statements.
6776 -- else
6777 -- case statement for accept alternatives.
6778 -- end if;
6780 declare
6781 Cases : Node_Id;
6782 Stmt : Node_Id;
6783 Parms : List_Id;
6784 Parm : Node_Id;
6785 Conv : Node_Id;
6787 begin
6788 -- The type of the delay expression is known to be legal
6790 if Time_Type = Standard_Duration then
6791 Conv := New_Reference_To (Delay_Min, Loc);
6793 elsif Is_RTE (Base_Type (Etype (Time_Type)), RO_CA_Time) then
6794 Conv := Make_Function_Call (Loc,
6795 New_Reference_To (RTE (RO_CA_To_Duration), Loc),
6796 New_List (New_Reference_To (Delay_Min, Loc)));
6798 else
6799 pragma Assert
6800 (Is_RTE (Base_Type (Etype (Time_Type)), RO_RT_Time));
6802 Conv := Make_Function_Call (Loc,
6803 New_Reference_To (RTE (RO_RT_To_Duration), Loc),
6804 New_List (New_Reference_To (Delay_Min, Loc)));
6805 end if;
6807 Stmt := Make_Assignment_Statement (Loc,
6808 Name => New_Reference_To (D, Loc),
6809 Expression => Conv);
6811 -- Change the value for Accept_Modes. (Else_Mode -> Delay_Mode)
6813 Parms := Parameter_Associations (Select_Call);
6814 Parm := First (Parms);
6816 while Present (Parm)
6817 and then Parm /= Select_Mode
6818 loop
6819 Next (Parm);
6820 end loop;
6822 pragma Assert (Present (Parm));
6823 Rewrite (Parm, New_Reference_To (RTE (RE_Delay_Mode), Loc));
6824 Analyze (Parm);
6826 -- Prepare two new parameters of Duration and Delay_Mode type
6827 -- which represent the value and the mode of the minimum delay.
6829 Next (Parm);
6830 Insert_After (Parm, New_Reference_To (M, Loc));
6831 Insert_After (Parm, New_Reference_To (D, Loc));
6833 -- Create a call to RTS
6835 Rewrite (Select_Call,
6836 Make_Procedure_Call_Statement (Loc,
6837 Name => New_Reference_To (RTE (RE_Timed_Selective_Wait), Loc),
6838 Parameter_Associations => Parms));
6840 -- This new call should follow the calculation of the
6841 -- minimum delay.
6843 Insert_List_Before (Select_Call, Delay_List);
6845 if Check_Guard then
6846 Stmt :=
6847 Make_Implicit_If_Statement (N,
6848 Condition => New_Reference_To (Guard_Open, Loc),
6849 Then_Statements =>
6850 New_List (New_Copy_Tree (Stmt),
6851 New_Copy_Tree (Select_Call)),
6852 Else_Statements => Accept_Or_Raise);
6853 Rewrite (Select_Call, Stmt);
6854 else
6855 Insert_Before (Select_Call, Stmt);
6856 end if;
6858 Cases :=
6859 Make_Implicit_If_Statement (N,
6860 Condition => Make_Op_Eq (Loc,
6861 Left_Opnd => New_Reference_To (Xnam, Loc),
6862 Right_Opnd =>
6863 New_Reference_To (RTE (RE_No_Rendezvous), Loc)),
6865 Then_Statements => Delay_Case,
6866 Else_Statements => Accept_Case);
6868 Append (Cases, Stats);
6869 end;
6870 end if;
6872 -- Replace accept statement with appropriate block
6874 Block :=
6875 Make_Block_Statement (Loc,
6876 Declarations => Decls,
6877 Handled_Statement_Sequence =>
6878 Make_Handled_Sequence_Of_Statements (Loc,
6879 Statements => Stats));
6881 Rewrite (N, Block);
6882 Analyze (N);
6884 -- Note: have to worry more about abort deferral in above code ???
6886 -- Final step is to unstack the Accept_Address entries for all accept
6887 -- statements appearing in accept alternatives in the select statement
6889 Alt := First (Alts);
6890 while Present (Alt) loop
6891 if Nkind (Alt) = N_Accept_Alternative then
6892 Remove_Last_Elmt (Accept_Address
6893 (Entity (Entry_Direct_Name (Accept_Statement (Alt)))));
6894 end if;
6896 Next (Alt);
6897 end loop;
6898 end Expand_N_Selective_Accept;
6900 --------------------------------------
6901 -- Expand_N_Single_Task_Declaration --
6902 --------------------------------------
6904 -- Single task declarations should never be present after semantic
6905 -- analysis, since we expect them to be replaced by a declaration of
6906 -- an anonymous task type, followed by a declaration of the task
6907 -- object. We include this routine to make sure that is happening!
6909 procedure Expand_N_Single_Task_Declaration (N : Node_Id) is
6910 begin
6911 raise Program_Error;
6912 end Expand_N_Single_Task_Declaration;
6914 ------------------------
6915 -- Expand_N_Task_Body --
6916 ------------------------
6918 -- Given a task body
6920 -- task body tname is
6921 -- <declarations>
6922 -- begin
6923 -- <statements>
6924 -- end x;
6926 -- This expansion routine converts it into a procedure and sets the
6927 -- elaboration flag for the procedure to true, to represent the fact
6928 -- that the task body is now elaborated:
6930 -- procedure tnameB (_Task : access tnameV) is
6931 -- discriminal : dtype renames _Task.discriminant;
6933 -- procedure _clean is
6934 -- begin
6935 -- Abort_Defer.all;
6936 -- Complete_Task;
6937 -- Abort_Undefer.all;
6938 -- return;
6939 -- end _clean;
6941 -- begin
6942 -- Abort_Undefer.all;
6943 -- <declarations>
6944 -- System.Task_Stages.Complete_Activation;
6945 -- <statements>
6946 -- at end
6947 -- _clean;
6948 -- end tnameB;
6950 -- tnameE := True;
6952 -- In addition, if the task body is an activator, then a call to
6953 -- activate tasks is added at the start of the statements, before
6954 -- the call to Complete_Activation, and if in addition the task is
6955 -- a master then it must be established as a master. These calls are
6956 -- inserted and analyzed in Expand_Cleanup_Actions, when the
6957 -- Handled_Sequence_Of_Statements is expanded.
6959 -- There is one discriminal declaration line generated for each
6960 -- discriminant that is present to provide an easy reference point
6961 -- for discriminant references inside the body (see Exp_Ch2.Expand_Name).
6963 -- Note on relationship to GNARLI definition. In the GNARLI definition,
6964 -- task body procedures have a profile (Arg : System.Address). That is
6965 -- needed because GNARLI has to use the same access-to-subprogram type
6966 -- for all task types. We depend here on knowing that in GNAT, passing
6967 -- an address argument by value is identical to passing a record value
6968 -- by access (in either case a single pointer is passed), so even though
6969 -- this procedure has the wrong profile. In fact it's all OK, since the
6970 -- callings sequence is identical.
6972 procedure Expand_N_Task_Body (N : Node_Id) is
6973 Loc : constant Source_Ptr := Sloc (N);
6974 Ttyp : constant Entity_Id := Corresponding_Spec (N);
6975 Call : Node_Id;
6976 New_N : Node_Id;
6978 begin
6979 -- Here we start the expansion by generating discriminal declarations
6981 Add_Discriminal_Declarations (Declarations (N), Ttyp, Name_uTask, Loc);
6983 -- Add a call to Abort_Undefer at the very beginning of the task
6984 -- body since this body is called with abort still deferred.
6986 if Abort_Allowed then
6987 Call := Build_Runtime_Call (Loc, RE_Abort_Undefer);
6988 Insert_Before
6989 (First (Statements (Handled_Statement_Sequence (N))), Call);
6990 Analyze (Call);
6991 end if;
6993 -- The statement part has already been protected with an at_end and
6994 -- cleanup actions. The call to Complete_Activation must be placed
6995 -- at the head of the sequence of statements of that block. The
6996 -- declarations have been merged in this sequence of statements but
6997 -- the first real statement is accessible from the First_Real_Statement
6998 -- field (which was set for exactly this purpose).
7000 if Restricted_Profile then
7001 Call := Build_Runtime_Call (Loc, RE_Complete_Restricted_Activation);
7002 else
7003 Call := Build_Runtime_Call (Loc, RE_Complete_Activation);
7004 end if;
7006 Insert_Before
7007 (First_Real_Statement (Handled_Statement_Sequence (N)), Call);
7008 Analyze (Call);
7010 New_N :=
7011 Make_Subprogram_Body (Loc,
7012 Specification => Build_Task_Proc_Specification (Ttyp),
7013 Declarations => Declarations (N),
7014 Handled_Statement_Sequence => Handled_Statement_Sequence (N));
7016 -- If the task contains generic instantiations, cleanup actions
7017 -- are delayed until after instantiation. Transfer the activation
7018 -- chain to the subprogram, to insure that the activation call is
7019 -- properly generated. It the task body contains inner tasks, indicate
7020 -- that the subprogram is a task master.
7022 if Delay_Cleanups (Ttyp) then
7023 Set_Activation_Chain_Entity (New_N, Activation_Chain_Entity (N));
7024 Set_Is_Task_Master (New_N, Is_Task_Master (N));
7025 end if;
7027 Rewrite (N, New_N);
7028 Analyze (N);
7030 -- Set elaboration flag immediately after task body. If the body
7031 -- is a subunit, the flag is set in the declarative part that
7032 -- contains the stub.
7034 if Nkind (Parent (N)) /= N_Subunit then
7035 Insert_After (N,
7036 Make_Assignment_Statement (Loc,
7037 Name =>
7038 Make_Identifier (Loc, New_External_Name (Chars (Ttyp), 'E')),
7039 Expression => New_Reference_To (Standard_True, Loc)));
7040 end if;
7041 end Expand_N_Task_Body;
7043 ------------------------------------
7044 -- Expand_N_Task_Type_Declaration --
7045 ------------------------------------
7047 -- We have several things to do. First we must create a Boolean flag used
7048 -- to mark if the body is elaborated yet. This variable gets set to True
7049 -- when the body of the task is elaborated (we can't rely on the normal
7050 -- ABE mechanism for the task body, since we need to pass an access to
7051 -- this elaboration boolean to the runtime routines).
7053 -- taskE : aliased Boolean := False;
7055 -- Next a variable is declared to hold the task stack size (either
7056 -- the default : Unspecified_Size, or a value that is set by a pragma
7057 -- Storage_Size). If the value of the pragma Storage_Size is static, then
7058 -- the variable is initialized with this value:
7060 -- taskZ : Size_Type := Unspecified_Size;
7061 -- or
7062 -- taskZ : Size_Type := Size_Type (size_expression);
7064 -- Next we create a corresponding record type declaration used to represent
7065 -- values of this task. The general form of this type declaration is
7067 -- type taskV (discriminants) is record
7068 -- _Task_Id : Task_Id;
7069 -- entry_family : array (bounds) of Void;
7070 -- _Priority : Integer := priority_expression;
7071 -- _Size : Size_Type := Size_Type (size_expression);
7072 -- _Task_Info : Task_Info_Type := task_info_expression;
7073 -- end record;
7075 -- The discriminants are present only if the corresponding task type has
7076 -- discriminants, and they exactly mirror the task type discriminants.
7078 -- The Id field is always present. It contains the Task_Id value, as
7079 -- set by the call to Create_Task. Note that although the task is
7080 -- limited, the task value record type is not limited, so there is no
7081 -- problem in passing this field as an out parameter to Create_Task.
7083 -- One entry_family component is present for each entry family in the
7084 -- task definition. The bounds correspond to the bounds of the entry
7085 -- family (which may depend on discriminants). The element type is
7086 -- void, since we only need the bounds information for determining
7087 -- the entry index. Note that the use of an anonymous array would
7088 -- normally be illegal in this context, but this is a parser check,
7089 -- and the semantics is quite prepared to handle such a case.
7091 -- The _Size field is present only if a Storage_Size pragma appears in
7092 -- the task definition. The expression captures the argument that was
7093 -- present in the pragma, and is used to override the task stack size
7094 -- otherwise associated with the task type.
7096 -- The _Priority field is present only if a Priority or Interrupt_Priority
7097 -- pragma appears in the task definition. The expression captures the
7098 -- argument that was present in the pragma, and is used to provide
7099 -- the Size parameter to the call to Create_Task.
7101 -- The _Task_Info field is present only if a Task_Info pragma appears in
7102 -- the task definition. The expression captures the argument that was
7103 -- present in the pragma, and is used to provide the Task_Image parameter
7104 -- to the call to Create_Task.
7106 -- When a task is declared, an instance of the task value record is
7107 -- created. The elaboration of this declaration creates the correct
7108 -- bounds for the entry families, and also evaluates the size, priority,
7109 -- and task_Info expressions if needed. The initialization routine for
7110 -- the task type itself then calls Create_Task with appropriate
7111 -- parameters to initialize the value of the Task_Id field.
7113 -- Note: the address of this record is passed as the "Discriminants"
7114 -- parameter for Create_Task. Since Create_Task merely passes this onto
7115 -- the body procedure, it does not matter that it does not quite match
7116 -- the GNARLI model of what is being passed (the record contains more
7117 -- than just the discriminants, but the discriminants can be found from
7118 -- the record value).
7120 -- The Entity_Id for this created record type is placed in the
7121 -- Corresponding_Record_Type field of the associated task type entity.
7123 -- Next we create a procedure specification for the task body procedure:
7125 -- procedure taskB (_Task : access taskV);
7127 -- Note that this must come after the record type declaration, since
7128 -- the spec refers to this type. It turns out that the initialization
7129 -- procedure for the value type references the task body spec, but that's
7130 -- fine, since it won't be generated till the freeze point for the type,
7131 -- which is certainly after the task body spec declaration.
7133 -- Finally, we set the task index value field of the entry attribute in
7134 -- the case of a simple entry.
7136 procedure Expand_N_Task_Type_Declaration (N : Node_Id) is
7137 Loc : constant Source_Ptr := Sloc (N);
7138 Tasktyp : constant Entity_Id := Etype (Defining_Identifier (N));
7139 Tasknm : constant Name_Id := Chars (Tasktyp);
7140 Taskdef : constant Node_Id := Task_Definition (N);
7142 Proc_Spec : Node_Id;
7143 Rec_Decl : Node_Id;
7144 Rec_Ent : Entity_Id;
7145 Cdecls : List_Id;
7146 Elab_Decl : Node_Id;
7147 Size_Decl : Node_Id;
7148 Body_Decl : Node_Id;
7149 Task_Size : Node_Id;
7150 Ent_Stack : Entity_Id;
7151 Decl_Stack : Node_Id;
7153 begin
7154 -- If already expanded, nothing to do
7156 if Present (Corresponding_Record_Type (Tasktyp)) then
7157 return;
7158 end if;
7160 -- Here we will do the expansion
7162 Rec_Decl := Build_Corresponding_Record (N, Tasktyp, Loc);
7163 Rec_Ent := Defining_Identifier (Rec_Decl);
7164 Cdecls := Component_Items (Component_List
7165 (Type_Definition (Rec_Decl)));
7167 Qualify_Entity_Names (N);
7169 -- First create the elaboration variable
7171 Elab_Decl :=
7172 Make_Object_Declaration (Loc,
7173 Defining_Identifier =>
7174 Make_Defining_Identifier (Sloc (Tasktyp),
7175 Chars => New_External_Name (Tasknm, 'E')),
7176 Aliased_Present => True,
7177 Object_Definition => New_Reference_To (Standard_Boolean, Loc),
7178 Expression => New_Reference_To (Standard_False, Loc));
7179 Insert_After (N, Elab_Decl);
7181 -- Next create the declaration of the size variable (tasknmZ)
7183 Set_Storage_Size_Variable (Tasktyp,
7184 Make_Defining_Identifier (Sloc (Tasktyp),
7185 Chars => New_External_Name (Tasknm, 'Z')));
7187 if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) and then
7188 Is_Static_Expression (Expression (First (
7189 Pragma_Argument_Associations (Find_Task_Or_Protected_Pragma (
7190 Taskdef, Name_Storage_Size)))))
7191 then
7192 Size_Decl :=
7193 Make_Object_Declaration (Loc,
7194 Defining_Identifier => Storage_Size_Variable (Tasktyp),
7195 Object_Definition => New_Reference_To (RTE (RE_Size_Type), Loc),
7196 Expression =>
7197 Convert_To (RTE (RE_Size_Type),
7198 Relocate_Node (
7199 Expression (First (
7200 Pragma_Argument_Associations (
7201 Find_Task_Or_Protected_Pragma
7202 (Taskdef, Name_Storage_Size)))))));
7204 else
7205 Size_Decl :=
7206 Make_Object_Declaration (Loc,
7207 Defining_Identifier => Storage_Size_Variable (Tasktyp),
7208 Object_Definition => New_Reference_To (RTE (RE_Size_Type), Loc),
7209 Expression => New_Reference_To (RTE (RE_Unspecified_Size), Loc));
7210 end if;
7212 Insert_After (Elab_Decl, Size_Decl);
7214 -- Next build the rest of the corresponding record declaration.
7215 -- This is done last, since the corresponding record initialization
7216 -- procedure will reference the previously created entities.
7218 -- Fill in the component declarations -- first the _Task_Id field
7220 Append_To (Cdecls,
7221 Make_Component_Declaration (Loc,
7222 Defining_Identifier =>
7223 Make_Defining_Identifier (Loc, Name_uTask_Id),
7224 Component_Definition =>
7225 Make_Component_Definition (Loc,
7226 Aliased_Present => False,
7227 Subtype_Indication => New_Reference_To (RTE (RO_ST_Task_Id),
7228 Loc))));
7230 -- Declare static ATCB (that is, created by the expander) if we
7231 -- are using the Restricted run time.
7233 if Restricted_Profile then
7234 Append_To (Cdecls,
7235 Make_Component_Declaration (Loc,
7236 Defining_Identifier =>
7237 Make_Defining_Identifier (Loc, Name_uATCB),
7239 Component_Definition =>
7240 Make_Component_Definition (Loc,
7241 Aliased_Present => True,
7242 Subtype_Indication => Make_Subtype_Indication (Loc,
7243 Subtype_Mark => New_Occurrence_Of
7244 (RTE (RE_Ada_Task_Control_Block), Loc),
7246 Constraint =>
7247 Make_Index_Or_Discriminant_Constraint (Loc,
7248 Constraints =>
7249 New_List (Make_Integer_Literal (Loc, 0)))))));
7251 end if;
7253 -- Declare static stack (that is, created by the expander) if we
7254 -- are using the Restricted run time on a bare board configuration.
7256 if Restricted_Profile
7257 and then Preallocated_Stacks_On_Target
7258 then
7259 -- First we need to extract the appropriate stack size
7261 Ent_Stack := Make_Defining_Identifier (Loc, Name_uStack);
7263 if Present (Taskdef) and then Has_Storage_Size_Pragma (Taskdef) then
7264 Task_Size := Relocate_Node (
7265 Expression (First (
7266 Pragma_Argument_Associations (
7267 Find_Task_Or_Protected_Pragma
7268 (Taskdef, Name_Storage_Size)))));
7269 else
7270 Task_Size :=
7271 New_Reference_To (RTE (RE_Default_Stack_Size), Loc);
7272 end if;
7274 Decl_Stack := Make_Component_Declaration (Loc,
7275 Defining_Identifier => Ent_Stack,
7277 Component_Definition =>
7278 Make_Component_Definition (Loc,
7279 Aliased_Present => True,
7280 Subtype_Indication => Make_Subtype_Indication (Loc,
7281 Subtype_Mark =>
7282 New_Occurrence_Of (RTE (RE_Storage_Array), Loc),
7284 Constraint =>
7285 Make_Index_Or_Discriminant_Constraint (Loc,
7286 Constraints => New_List (Make_Range (Loc,
7287 Low_Bound => Make_Integer_Literal (Loc, 1),
7288 High_Bound => Convert_To (RTE (RE_Storage_Offset),
7289 Task_Size)))))));
7291 Append_To (Cdecls, Decl_Stack);
7293 -- The appropriate alignment for the stack is ensured by the
7294 -- run-time code in charge of task creation.
7296 end if;
7298 -- Add components for entry families
7300 Collect_Entry_Families (Loc, Cdecls, Size_Decl, Tasktyp);
7302 -- Add the _Priority component if a Priority pragma is present
7304 if Present (Taskdef) and then Has_Priority_Pragma (Taskdef) then
7305 declare
7306 Prag : constant Node_Id :=
7307 Find_Task_Or_Protected_Pragma (Taskdef, Name_Priority);
7308 Expr : Node_Id;
7310 begin
7311 Expr := First (Pragma_Argument_Associations (Prag));
7313 if Nkind (Expr) = N_Pragma_Argument_Association then
7314 Expr := Expression (Expr);
7315 end if;
7317 Expr := New_Copy_Tree (Expr);
7319 -- Add conversion to proper type to do range check if required
7320 -- Note that for runtime units, we allow out of range interrupt
7321 -- priority values to be used in a priority pragma. This is for
7322 -- the benefit of some versions of System.Interrupts which use
7323 -- a special server task with maximum interrupt priority.
7325 if Chars (Prag) = Name_Priority
7326 and then not GNAT_Mode
7327 then
7328 Rewrite (Expr, Convert_To (RTE (RE_Priority), Expr));
7329 else
7330 Rewrite (Expr, Convert_To (RTE (RE_Any_Priority), Expr));
7331 end if;
7333 Append_To (Cdecls,
7334 Make_Component_Declaration (Loc,
7335 Defining_Identifier =>
7336 Make_Defining_Identifier (Loc, Name_uPriority),
7337 Component_Definition =>
7338 Make_Component_Definition (Loc,
7339 Aliased_Present => False,
7340 Subtype_Indication => New_Reference_To (Standard_Integer,
7341 Loc)),
7342 Expression => Expr));
7343 end;
7344 end if;
7346 -- Add the _Task_Size component if a Storage_Size pragma is present
7348 if Present (Taskdef)
7349 and then Has_Storage_Size_Pragma (Taskdef)
7350 then
7351 Append_To (Cdecls,
7352 Make_Component_Declaration (Loc,
7353 Defining_Identifier =>
7354 Make_Defining_Identifier (Loc, Name_uSize),
7356 Component_Definition =>
7357 Make_Component_Definition (Loc,
7358 Aliased_Present => False,
7359 Subtype_Indication => New_Reference_To (RTE (RE_Size_Type),
7360 Loc)),
7362 Expression =>
7363 Convert_To (RTE (RE_Size_Type),
7364 Relocate_Node (
7365 Expression (First (
7366 Pragma_Argument_Associations (
7367 Find_Task_Or_Protected_Pragma
7368 (Taskdef, Name_Storage_Size))))))));
7369 end if;
7371 -- Add the _Task_Info component if a Task_Info pragma is present
7373 if Present (Taskdef) and then Has_Task_Info_Pragma (Taskdef) then
7374 Append_To (Cdecls,
7375 Make_Component_Declaration (Loc,
7376 Defining_Identifier =>
7377 Make_Defining_Identifier (Loc, Name_uTask_Info),
7379 Component_Definition =>
7380 Make_Component_Definition (Loc,
7381 Aliased_Present => False,
7382 Subtype_Indication =>
7383 New_Reference_To (RTE (RE_Task_Info_Type), Loc)),
7385 Expression => New_Copy (
7386 Expression (First (
7387 Pragma_Argument_Associations (
7388 Find_Task_Or_Protected_Pragma
7389 (Taskdef, Name_Task_Info)))))));
7390 end if;
7392 Insert_After (Size_Decl, Rec_Decl);
7394 -- Analyze the record declaration immediately after construction,
7395 -- because the initialization procedure is needed for single task
7396 -- declarations before the next entity is analyzed.
7398 Analyze (Rec_Decl);
7400 -- Create the declaration of the task body procedure
7402 Proc_Spec := Build_Task_Proc_Specification (Tasktyp);
7403 Body_Decl :=
7404 Make_Subprogram_Declaration (Loc,
7405 Specification => Proc_Spec);
7407 Insert_After (Rec_Decl, Body_Decl);
7409 -- The subprogram does not comes from source, so we have to indicate
7410 -- the need for debugging information explicitly.
7412 Set_Needs_Debug_Info
7413 (Defining_Entity (Proc_Spec), Comes_From_Source (Original_Node (N)));
7415 -- Now we can freeze the corresponding record. This needs manually
7416 -- freezing, since it is really part of the task type, and the task
7417 -- type is frozen at this stage. We of course need the initialization
7418 -- procedure for this corresponding record type and we won't get it
7419 -- in time if we don't freeze now.
7421 declare
7422 L : constant List_Id := Freeze_Entity (Rec_Ent, Loc);
7424 begin
7425 if Is_Non_Empty_List (L) then
7426 Insert_List_After (Body_Decl, L);
7427 end if;
7428 end;
7430 -- Complete the expansion of access types to the current task
7431 -- type, if any were declared.
7433 Expand_Previous_Access_Type (Tasktyp);
7434 end Expand_N_Task_Type_Declaration;
7436 -------------------------------
7437 -- Expand_N_Timed_Entry_Call --
7438 -------------------------------
7440 -- A timed entry call in normal case is not implemented using ATC
7441 -- mechanism anymore for efficiency reason.
7443 -- select
7444 -- T.E;
7445 -- S1;
7446 -- or
7447 -- Delay D;
7448 -- S2;
7449 -- end select;
7451 -- is expanded as follow:
7453 -- 1) When T.E is a task entry_call;
7455 -- declare
7456 -- B : Boolean;
7457 -- X : Task_Entry_Index := <entry index>;
7458 -- DX : Duration := To_Duration (D);
7459 -- M : Delay_Mode := <discriminant>;
7460 -- P : parms := (parm, parm, parm);
7462 -- begin
7463 -- Timed_Protected_Entry_Call (<acceptor-task>, X, P'Address,
7464 -- DX, M, B);
7465 -- if B then
7466 -- S1;
7467 -- else
7468 -- S2;
7469 -- end if;
7470 -- end;
7472 -- 2) When T.E is a protected entry_call;
7474 -- declare
7475 -- B : Boolean;
7476 -- X : Protected_Entry_Index := <entry index>;
7477 -- DX : Duration := To_Duration (D);
7478 -- M : Delay_Mode := <discriminant>;
7479 -- P : parms := (parm, parm, parm);
7481 -- begin
7482 -- Timed_Protected_Entry_Call (<object>'unchecked_access, X,
7483 -- P'Address, DX, M, B);
7484 -- if B then
7485 -- S1;
7486 -- else
7487 -- S2;
7488 -- end if;
7489 -- end;
7491 procedure Expand_N_Timed_Entry_Call (N : Node_Id) is
7492 Loc : constant Source_Ptr := Sloc (N);
7494 E_Call : Node_Id :=
7495 Entry_Call_Statement (Entry_Call_Alternative (N));
7496 E_Stats : constant List_Id :=
7497 Statements (Entry_Call_Alternative (N));
7498 D_Stat : constant Node_Id :=
7499 Delay_Statement (Delay_Alternative (N));
7500 D_Stats : constant List_Id :=
7501 Statements (Delay_Alternative (N));
7503 Stmts : List_Id;
7504 Stmt : Node_Id;
7505 Parms : List_Id;
7506 Parm : Node_Id;
7508 Concval : Node_Id;
7509 Ename : Node_Id;
7510 Index : Node_Id;
7512 Decls : List_Id;
7513 Disc : Node_Id;
7514 Conv : Node_Id;
7515 B : Entity_Id;
7516 D : Entity_Id;
7517 Dtyp : Entity_Id;
7518 M : Entity_Id;
7520 Call : Node_Id;
7521 Dummy : Node_Id;
7523 begin
7524 -- The arguments in the call may require dynamic allocation, and the
7525 -- call statement may have been transformed into a block. The block
7526 -- may contain additional declarations for internal entities, and the
7527 -- original call is found by sequential search.
7529 if Nkind (E_Call) = N_Block_Statement then
7530 E_Call := First (Statements (Handled_Statement_Sequence (E_Call)));
7532 while Nkind (E_Call) /= N_Procedure_Call_Statement
7533 and then Nkind (E_Call) /= N_Entry_Call_Statement
7534 loop
7535 Next (E_Call);
7536 end loop;
7537 end if;
7539 -- Build an entry call using Simple_Entry_Call. We will use this as the
7540 -- base for creating appropriate calls.
7542 Extract_Entry (E_Call, Concval, Ename, Index);
7543 Build_Simple_Entry_Call (E_Call, Concval, Ename, Index);
7545 Stmts := Statements (Handled_Statement_Sequence (E_Call));
7546 Decls := Declarations (E_Call);
7548 if No (Decls) then
7549 Decls := New_List;
7550 end if;
7552 Dtyp := Base_Type (Etype (Expression (D_Stat)));
7554 -- Use the type of the delay expression (Calendar or Real_Time)
7555 -- to generate the appropriate conversion.
7557 if Nkind (D_Stat) = N_Delay_Relative_Statement then
7558 Disc := Make_Integer_Literal (Loc, 0);
7559 Conv := Relocate_Node (Expression (D_Stat));
7561 elsif Is_RTE (Dtyp, RO_CA_Time) then
7562 Disc := Make_Integer_Literal (Loc, 1);
7563 Conv := Make_Function_Call (Loc,
7564 New_Reference_To (RTE (RO_CA_To_Duration), Loc),
7565 New_List (New_Copy (Expression (D_Stat))));
7567 else pragma Assert (Is_RTE (Dtyp, RO_RT_Time));
7568 Disc := Make_Integer_Literal (Loc, 2);
7569 Conv := Make_Function_Call (Loc,
7570 New_Reference_To (RTE (RO_RT_To_Duration), Loc),
7571 New_List (New_Copy (Expression (D_Stat))));
7572 end if;
7574 -- Create Duration and Delay_Mode objects for passing a delay value
7576 D := Make_Defining_Identifier (Loc, New_Internal_Name ('D'));
7577 M := Make_Defining_Identifier (Loc, New_Internal_Name ('M'));
7579 Append_To (Decls,
7580 Make_Object_Declaration (Loc,
7581 Defining_Identifier => D,
7582 Object_Definition => New_Reference_To (Standard_Duration, Loc)));
7584 Append_To (Decls,
7585 Make_Object_Declaration (Loc,
7586 Defining_Identifier => M,
7587 Object_Definition => New_Reference_To (Standard_Integer, Loc),
7588 Expression => Disc));
7590 B := Make_Defining_Identifier (Loc, Name_uB);
7592 -- Create a boolean object used for a return parameter
7594 Prepend_To (Decls,
7595 Make_Object_Declaration (Loc,
7596 Defining_Identifier => B,
7597 Object_Definition => New_Reference_To (Standard_Boolean, Loc)));
7599 Stmt := First (Stmts);
7601 -- Skip assignments to temporaries created for in-out parameters.
7602 -- This makes unwarranted assumptions about the shape of the expanded
7603 -- tree for the call, and should be cleaned up ???
7605 while Nkind (Stmt) /= N_Procedure_Call_Statement loop
7606 Next (Stmt);
7607 end loop;
7609 -- Do the assignement at this stage only because the evaluation of the
7610 -- expression must not occur before (see ACVC C97302A).
7612 Insert_Before (Stmt,
7613 Make_Assignment_Statement (Loc,
7614 Name => New_Reference_To (D, Loc),
7615 Expression => Conv));
7617 Call := Stmt;
7619 Parms := Parameter_Associations (Call);
7621 -- For a protected type, we build a Timed_Protected_Entry_Call
7623 if Is_Protected_Type (Etype (Concval)) then
7625 -- Create a new call statement
7627 Parm := First (Parms);
7629 while Present (Parm)
7630 and then not Is_RTE (Etype (Parm), RE_Call_Modes)
7631 loop
7632 Next (Parm);
7633 end loop;
7635 Dummy := Remove_Next (Next (Parm));
7637 -- Remove garbage is following the Cancel_Param if present
7639 Dummy := Next (Parm);
7641 -- Remove the mode of the Protected_Entry_Call call, then remove the
7642 -- Communication_Block of the Protected_Entry_Call call, and finally
7643 -- add Duration and a Delay_Mode parameter
7645 pragma Assert (Present (Parm));
7646 Rewrite (Parm, New_Reference_To (D, Loc));
7648 Rewrite (Dummy, New_Reference_To (M, Loc));
7650 -- Add a Boolean flag for successful entry call
7652 Append_To (Parms, New_Reference_To (B, Loc));
7654 if Abort_Allowed
7655 or else Restriction_Active (No_Entry_Queue) = False
7656 or else Number_Entries (Etype (Concval)) > 1
7657 then
7658 Rewrite (Call,
7659 Make_Procedure_Call_Statement (Loc,
7660 Name =>
7661 New_Reference_To (RTE (RE_Timed_Protected_Entry_Call), Loc),
7662 Parameter_Associations => Parms));
7664 else
7665 Parm := First (Parms);
7667 while Present (Parm)
7668 and then not Is_RTE (Etype (Parm), RE_Protected_Entry_Index)
7669 loop
7670 Next (Parm);
7671 end loop;
7673 Remove (Parm);
7675 Rewrite (Call,
7676 Make_Procedure_Call_Statement (Loc,
7677 Name => New_Reference_To (
7678 RTE (RE_Timed_Protected_Single_Entry_Call), Loc),
7679 Parameter_Associations => Parms));
7680 end if;
7682 -- For the task case, build a Timed_Task_Entry_Call
7684 else
7685 -- Create a new call statement
7687 Append_To (Parms, New_Reference_To (D, Loc));
7688 Append_To (Parms, New_Reference_To (M, Loc));
7689 Append_To (Parms, New_Reference_To (B, Loc));
7691 Rewrite (Call,
7692 Make_Procedure_Call_Statement (Loc,
7693 Name => New_Reference_To (RTE (RE_Timed_Task_Entry_Call), Loc),
7694 Parameter_Associations => Parms));
7696 end if;
7698 Append_To (Stmts,
7699 Make_Implicit_If_Statement (N,
7700 Condition => New_Reference_To (B, Loc),
7701 Then_Statements => E_Stats,
7702 Else_Statements => D_Stats));
7704 Rewrite (N,
7705 Make_Block_Statement (Loc,
7706 Declarations => Decls,
7707 Handled_Statement_Sequence =>
7708 Make_Handled_Sequence_Of_Statements (Loc, Stmts)));
7710 Analyze (N);
7711 end Expand_N_Timed_Entry_Call;
7713 ----------------------------------------
7714 -- Expand_Protected_Body_Declarations --
7715 ----------------------------------------
7717 -- Part of the expansion of a protected body involves the creation of
7718 -- a declaration that can be referenced from the statement sequences of
7719 -- the entry bodies:
7721 -- A : Address;
7723 -- This declaration is inserted in the declarations of the service
7724 -- entries procedure for the protected body, and it is important that
7725 -- it be inserted before the statements of the entry body statement
7726 -- sequences are analyzed. Thus it would be too late to create this
7727 -- declaration in the Expand_N_Protected_Body routine, which is why
7728 -- there is a separate procedure to be called directly from Sem_Ch9.
7730 -- Ann is used to hold the address of the record containing the parameters
7731 -- (see Expand_N_Entry_Call for more details on how this record is built).
7732 -- References to the parameters do an unchecked conversion of this address
7733 -- to a pointer to the required record type, and then access the field that
7734 -- holds the value of the required parameter. The entity for the address
7735 -- variable is held as the top stack element (i.e. the last element) of the
7736 -- Accept_Address stack in the corresponding entry entity, and this element
7737 -- must be set in place before the statements are processed.
7739 -- No stack is needed for entry bodies, since they cannot be nested, but
7740 -- it is kept for consistency between protected and task entries. The
7741 -- stack will never contain more than one element. There is also only one
7742 -- such variable for a given protected body, but this is placed on the
7743 -- Accept_Address stack of all of the entries, again for consistency.
7745 -- To expand the requeue statement, a label is provided at the end of
7746 -- the loop in the entry service routine created by the expander (see
7747 -- Expand_N_Protected_Body for details), so that the statement can be
7748 -- skipped after the requeue is complete. This label is created during the
7749 -- expansion of the entry body, which will take place after the expansion
7750 -- of the requeue statements that it contains, so a placeholder defining
7751 -- identifier is associated with the task type here.
7753 -- Another label is provided following case statement created by the
7754 -- expander. This label is need for implementing return statement from
7755 -- entry body so that a return can be expanded as a goto to this label.
7756 -- This label is created during the expansion of the entry body, which
7757 -- will take place after the expansion of the return statements that it
7758 -- contains. Therefore, just like the label for expanding requeues, we
7759 -- need another placeholder for the label.
7761 procedure Expand_Protected_Body_Declarations
7762 (N : Node_Id;
7763 Spec_Id : Entity_Id)
7765 Op : Node_Id;
7767 begin
7768 if No_Run_Time_Mode then
7769 Error_Msg_CRT ("protected body", N);
7770 return;
7772 elsif Expander_Active then
7774 -- Associate privals with the first subprogram or entry
7775 -- body to be expanded. These are used to expand references
7776 -- to private data objects.
7778 Op := First_Protected_Operation (Declarations (N));
7780 if Present (Op) then
7781 Set_Discriminals (Parent (Spec_Id));
7782 Set_Privals (Parent (Spec_Id), Op, Sloc (N));
7783 end if;
7784 end if;
7785 end Expand_Protected_Body_Declarations;
7787 -------------------------
7788 -- External_Subprogram --
7789 -------------------------
7791 function External_Subprogram (E : Entity_Id) return Entity_Id is
7792 Subp : constant Entity_Id := Protected_Body_Subprogram (E);
7793 Decl : constant Node_Id := Unit_Declaration_Node (E);
7795 begin
7796 -- If the protected operation is defined in the visible part of the
7797 -- protected type, or if it is an interrupt handler, the internal and
7798 -- external subprograms follow each other on the entity chain. If the
7799 -- operation is defined in the private part of the type, there is no
7800 -- need for a separate locking version of the operation, and internal
7801 -- calls use the protected_body_subprogram directly.
7803 if List_Containing (Decl) = Visible_Declarations (Parent (Decl))
7804 or else Is_Interrupt_Handler (E)
7805 then
7806 return Next_Entity (Subp);
7807 else
7808 return (Subp);
7809 end if;
7810 end External_Subprogram;
7812 -------------------
7813 -- Extract_Entry --
7814 -------------------
7816 procedure Extract_Entry
7817 (N : Node_Id;
7818 Concval : out Node_Id;
7819 Ename : out Node_Id;
7820 Index : out Node_Id)
7822 Nam : constant Node_Id := Name (N);
7824 begin
7825 -- For a simple entry, the name is a selected component, with the
7826 -- prefix being the task value, and the selector being the entry.
7828 if Nkind (Nam) = N_Selected_Component then
7829 Concval := Prefix (Nam);
7830 Ename := Selector_Name (Nam);
7831 Index := Empty;
7833 -- For a member of an entry family, the name is an indexed
7834 -- component where the prefix is a selected component,
7835 -- whose prefix in turn is the task value, and whose
7836 -- selector is the entry family. The single expression in
7837 -- the expressions list of the indexed component is the
7838 -- subscript for the family.
7840 else
7841 pragma Assert (Nkind (Nam) = N_Indexed_Component);
7842 Concval := Prefix (Prefix (Nam));
7843 Ename := Selector_Name (Prefix (Nam));
7844 Index := First (Expressions (Nam));
7845 end if;
7846 end Extract_Entry;
7848 -------------------
7849 -- Family_Offset --
7850 -------------------
7852 function Family_Offset
7853 (Loc : Source_Ptr;
7854 Hi : Node_Id;
7855 Lo : Node_Id;
7856 Ttyp : Entity_Id) return Node_Id
7858 function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id;
7859 -- If one of the bounds is a reference to a discriminant, replace
7860 -- with corresponding discriminal of type. Within the body of a task
7861 -- retrieve the renamed discriminant by simple visibility, using its
7862 -- generated name. Within a protected object, find the original dis-
7863 -- criminant and replace it with the discriminal of the current prot-
7864 -- ected operation.
7866 ------------------------------
7867 -- Convert_Discriminant_Ref --
7868 ------------------------------
7870 function Convert_Discriminant_Ref (Bound : Node_Id) return Node_Id is
7871 Loc : constant Source_Ptr := Sloc (Bound);
7872 B : Node_Id;
7873 D : Entity_Id;
7875 begin
7876 if Is_Entity_Name (Bound)
7877 and then Ekind (Entity (Bound)) = E_Discriminant
7878 then
7879 if Is_Task_Type (Ttyp)
7880 and then Has_Completion (Ttyp)
7881 then
7882 B := Make_Identifier (Loc, Chars (Entity (Bound)));
7883 Find_Direct_Name (B);
7885 elsif Is_Protected_Type (Ttyp) then
7886 D := First_Discriminant (Ttyp);
7888 while Chars (D) /= Chars (Entity (Bound)) loop
7889 Next_Discriminant (D);
7890 end loop;
7892 B := New_Reference_To (Discriminal (D), Loc);
7894 else
7895 B := New_Reference_To (Discriminal (Entity (Bound)), Loc);
7896 end if;
7898 elsif Nkind (Bound) = N_Attribute_Reference then
7899 return Bound;
7901 else
7902 B := New_Copy_Tree (Bound);
7903 end if;
7905 return
7906 Make_Attribute_Reference (Loc,
7907 Attribute_Name => Name_Pos,
7908 Prefix => New_Occurrence_Of (Etype (Bound), Loc),
7909 Expressions => New_List (B));
7910 end Convert_Discriminant_Ref;
7912 -- Start of processing for Family_Offset
7914 begin
7915 return
7916 Make_Op_Subtract (Loc,
7917 Left_Opnd => Convert_Discriminant_Ref (Hi),
7918 Right_Opnd => Convert_Discriminant_Ref (Lo));
7919 end Family_Offset;
7921 -----------------
7922 -- Family_Size --
7923 -----------------
7925 function Family_Size
7926 (Loc : Source_Ptr;
7927 Hi : Node_Id;
7928 Lo : Node_Id;
7929 Ttyp : Entity_Id) return Node_Id
7931 Ityp : Entity_Id;
7933 begin
7934 if Is_Task_Type (Ttyp) then
7935 Ityp := RTE (RE_Task_Entry_Index);
7936 else
7937 Ityp := RTE (RE_Protected_Entry_Index);
7938 end if;
7940 return
7941 Make_Attribute_Reference (Loc,
7942 Prefix => New_Reference_To (Ityp, Loc),
7943 Attribute_Name => Name_Max,
7944 Expressions => New_List (
7945 Make_Op_Add (Loc,
7946 Left_Opnd =>
7947 Family_Offset (Loc, Hi, Lo, Ttyp),
7948 Right_Opnd =>
7949 Make_Integer_Literal (Loc, 1)),
7950 Make_Integer_Literal (Loc, 0)));
7951 end Family_Size;
7953 -----------------------------------
7954 -- Find_Task_Or_Protected_Pragma --
7955 -----------------------------------
7957 function Find_Task_Or_Protected_Pragma
7958 (T : Node_Id;
7959 P : Name_Id) return Node_Id
7961 N : Node_Id;
7963 begin
7964 N := First (Visible_Declarations (T));
7966 while Present (N) loop
7967 if Nkind (N) = N_Pragma then
7968 if Chars (N) = P then
7969 return N;
7971 elsif P = Name_Priority
7972 and then Chars (N) = Name_Interrupt_Priority
7973 then
7974 return N;
7976 else
7977 Next (N);
7978 end if;
7980 else
7981 Next (N);
7982 end if;
7983 end loop;
7985 N := First (Private_Declarations (T));
7987 while Present (N) loop
7988 if Nkind (N) = N_Pragma then
7989 if Chars (N) = P then
7990 return N;
7992 elsif P = Name_Priority
7993 and then Chars (N) = Name_Interrupt_Priority
7994 then
7995 return N;
7997 else
7998 Next (N);
7999 end if;
8001 else
8002 Next (N);
8003 end if;
8004 end loop;
8006 raise Program_Error;
8007 end Find_Task_Or_Protected_Pragma;
8009 -------------------------------
8010 -- First_Protected_Operation --
8011 -------------------------------
8013 function First_Protected_Operation (D : List_Id) return Node_Id is
8014 First_Op : Node_Id;
8016 begin
8017 First_Op := First (D);
8018 while Present (First_Op)
8019 and then Nkind (First_Op) /= N_Subprogram_Body
8020 and then Nkind (First_Op) /= N_Entry_Body
8021 loop
8022 Next (First_Op);
8023 end loop;
8025 return First_Op;
8026 end First_Protected_Operation;
8028 --------------------------------
8029 -- Index_Constant_Declaration --
8030 --------------------------------
8032 function Index_Constant_Declaration
8033 (N : Node_Id;
8034 Index_Id : Entity_Id;
8035 Prot : Entity_Id) return List_Id
8037 Loc : constant Source_Ptr := Sloc (N);
8038 Decls : constant List_Id := New_List;
8039 Index_Con : constant Entity_Id := Entry_Index_Constant (Index_Id);
8040 Index_Typ : Entity_Id;
8042 Hi : Node_Id := Type_High_Bound (Etype (Index_Id));
8043 Lo : Node_Id := Type_Low_Bound (Etype (Index_Id));
8045 function Replace_Discriminant (Bound : Node_Id) return Node_Id;
8046 -- The bounds of the entry index may depend on discriminants, so
8047 -- each declaration of an entry_index_constant must have its own
8048 -- subtype declaration, using the local renaming of the object discri-
8049 -- minant.
8051 --------------------------
8052 -- Replace_Discriminant --
8053 --------------------------
8055 function Replace_Discriminant (Bound : Node_Id) return Node_Id is
8056 begin
8057 if Nkind (Bound) = N_Identifier
8058 and then Ekind (Entity (Bound)) = E_Constant
8059 and then Present (Discriminal_Link (Entity (Bound)))
8060 then
8061 return Make_Identifier (Loc, Chars (Entity (Bound)));
8062 else
8063 return Duplicate_Subexpr (Bound);
8064 end if;
8065 end Replace_Discriminant;
8067 -- Start of processing for Index_Constant_Declaration
8069 begin
8070 Set_Discriminal_Link (Index_Con, Index_Id);
8072 if Is_Entity_Name (
8073 Original_Node (Discrete_Subtype_Definition (Parent (Index_Id))))
8074 then
8075 -- Simple case: entry family is given by a subtype mark, and index
8076 -- constant has the same type, no replacement needed.
8078 Index_Typ := Etype (Index_Id);
8080 else
8081 Hi := Replace_Discriminant (Hi);
8082 Lo := Replace_Discriminant (Lo);
8084 Index_Typ := Make_Defining_Identifier (Loc, New_Internal_Name ('J'));
8086 Append (
8087 Make_Subtype_Declaration (Loc,
8088 Defining_Identifier => Index_Typ,
8089 Subtype_Indication =>
8090 Make_Subtype_Indication (Loc,
8091 Subtype_Mark =>
8092 New_Occurrence_Of (Base_Type (Etype (Index_Id)), Loc),
8093 Constraint =>
8094 Make_Range_Constraint (Loc,
8095 Range_Expression => Make_Range (Loc, Lo, Hi)))),
8096 Decls);
8098 end if;
8100 Append (
8101 Make_Object_Declaration (Loc,
8102 Defining_Identifier => Index_Con,
8103 Constant_Present => True,
8104 Object_Definition => New_Occurrence_Of (Index_Typ, Loc),
8106 Expression =>
8107 Make_Attribute_Reference (Loc,
8108 Prefix => New_Reference_To (Index_Typ, Loc),
8109 Attribute_Name => Name_Val,
8111 Expressions => New_List (
8113 Make_Op_Add (Loc,
8114 Left_Opnd =>
8115 Make_Op_Subtract (Loc,
8116 Left_Opnd => Make_Identifier (Loc, Name_uE),
8117 Right_Opnd =>
8118 Entry_Index_Expression (Loc,
8119 Defining_Identifier (N), Empty, Prot)),
8121 Right_Opnd =>
8122 Make_Attribute_Reference (Loc,
8123 Prefix => New_Reference_To (Index_Typ, Loc),
8124 Attribute_Name => Name_Pos,
8125 Expressions => New_List (
8126 Make_Attribute_Reference (Loc,
8127 Prefix => New_Reference_To (Index_Typ, Loc),
8128 Attribute_Name => Name_First))))))),
8129 Decls);
8131 return Decls;
8132 end Index_Constant_Declaration;
8134 --------------------------------
8135 -- Make_Initialize_Protection --
8136 --------------------------------
8138 function Make_Initialize_Protection
8139 (Protect_Rec : Entity_Id) return List_Id
8141 Loc : constant Source_Ptr := Sloc (Protect_Rec);
8142 P_Arr : Entity_Id;
8143 Pdef : Node_Id;
8144 Pdec : Node_Id;
8145 Ptyp : constant Node_Id :=
8146 Corresponding_Concurrent_Type (Protect_Rec);
8147 Args : List_Id;
8148 L : constant List_Id := New_List;
8149 Has_Entry : constant Boolean := Has_Entries (Ptyp);
8150 Restricted : constant Boolean := Restricted_Profile;
8152 begin
8153 -- We may need two calls to properly initialize the object, one
8154 -- to Initialize_Protection, and possibly one to Install_Handlers
8155 -- if we have a pragma Attach_Handler.
8157 -- Get protected declaration. In the case of a task type declaration,
8158 -- this is simply the parent of the protected type entity.
8159 -- In the single protected object
8160 -- declaration, this parent will be the implicit type, and we can find
8161 -- the corresponding single protected object declaration by
8162 -- searching forward in the declaration list in the tree.
8163 -- ??? I am not sure that the test for N_Single_Protected_Declaration
8164 -- is needed here. Nodes of this type should have been removed
8165 -- during semantic analysis.
8167 Pdec := Parent (Ptyp);
8169 while Nkind (Pdec) /= N_Protected_Type_Declaration
8170 and then Nkind (Pdec) /= N_Single_Protected_Declaration
8171 loop
8172 Next (Pdec);
8173 end loop;
8175 -- Now we can find the object definition from this declaration
8177 Pdef := Protected_Definition (Pdec);
8179 -- Build the parameter list for the call. Note that _Init is the name
8180 -- of the formal for the object to be initialized, which is the task
8181 -- value record itself.
8183 Args := New_List;
8185 -- Object parameter. This is a pointer to the object of type
8186 -- Protection used by the GNARL to control the protected object.
8188 Append_To (Args,
8189 Make_Attribute_Reference (Loc,
8190 Prefix =>
8191 Make_Selected_Component (Loc,
8192 Prefix => Make_Identifier (Loc, Name_uInit),
8193 Selector_Name => Make_Identifier (Loc, Name_uObject)),
8194 Attribute_Name => Name_Unchecked_Access));
8196 -- Priority parameter. Set to Unspecified_Priority unless there is a
8197 -- priority pragma, in which case we take the value from the pragma,
8198 -- or there is an interrupt pragma and no priority pragma, and we
8199 -- set the ceiling to Interrupt_Priority'Last, an implementation-
8200 -- defined value, see D.3(10).
8202 if Present (Pdef)
8203 and then Has_Priority_Pragma (Pdef)
8204 then
8205 Append_To (Args,
8206 Duplicate_Subexpr_No_Checks
8207 (Expression
8208 (First
8209 (Pragma_Argument_Associations
8210 (Find_Task_Or_Protected_Pragma (Pdef, Name_Priority))))));
8212 elsif Has_Interrupt_Handler (Ptyp)
8213 or else Has_Attach_Handler (Ptyp)
8214 then
8215 -- When no priority is specified but an xx_Handler pragma is,
8216 -- we default to System.Interrupts.Default_Interrupt_Priority,
8217 -- see D.3(10).
8219 Append_To (Args,
8220 New_Reference_To (RTE (RE_Default_Interrupt_Priority), Loc));
8222 else
8223 Append_To (Args,
8224 New_Reference_To (RTE (RE_Unspecified_Priority), Loc));
8225 end if;
8227 if Has_Entry
8228 or else Has_Interrupt_Handler (Ptyp)
8229 or else Has_Attach_Handler (Ptyp)
8230 then
8231 -- Compiler_Info parameter. This parameter allows entry body
8232 -- procedures and barrier functions to be called from the runtime.
8233 -- It is a pointer to the record generated by the compiler to
8234 -- represent the protected object.
8236 if Has_Entry or else not Restricted then
8237 Append_To (Args,
8238 Make_Attribute_Reference (Loc,
8239 Prefix => Make_Identifier (Loc, Name_uInit),
8240 Attribute_Name => Name_Address));
8241 end if;
8243 if Has_Entry then
8244 -- Entry_Bodies parameter. This is a pointer to an array of
8245 -- pointers to the entry body procedures and barrier functions
8246 -- of the object. If the protected type has no entries this
8247 -- object will not exist; in this case, pass a null.
8249 P_Arr := Entry_Bodies_Array (Ptyp);
8251 Append_To (Args,
8252 Make_Attribute_Reference (Loc,
8253 Prefix => New_Reference_To (P_Arr, Loc),
8254 Attribute_Name => Name_Unrestricted_Access));
8256 if Abort_Allowed
8257 or else Restriction_Active (No_Entry_Queue) = False
8258 or else Number_Entries (Ptyp) > 1
8259 then
8260 -- Find index mapping function (clumsy but ok for now)
8262 while Ekind (P_Arr) /= E_Function loop
8263 Next_Entity (P_Arr);
8264 end loop;
8266 Append_To (Args,
8267 Make_Attribute_Reference (Loc,
8268 Prefix =>
8269 New_Reference_To (P_Arr, Loc),
8270 Attribute_Name => Name_Unrestricted_Access));
8271 end if;
8273 elsif not Restricted then
8274 Append_To (Args, Make_Null (Loc));
8275 Append_To (Args, Make_Null (Loc));
8276 end if;
8278 if Abort_Allowed
8279 or else Restriction_Active (No_Entry_Queue) = False
8280 or else Number_Entries (Ptyp) > 1
8281 then
8282 Append_To (L,
8283 Make_Procedure_Call_Statement (Loc,
8284 Name => New_Reference_To (
8285 RTE (RE_Initialize_Protection_Entries), Loc),
8286 Parameter_Associations => Args));
8288 elsif not Has_Entry and then Restricted then
8289 Append_To (L,
8290 Make_Procedure_Call_Statement (Loc,
8291 Name => New_Reference_To (
8292 RTE (RE_Initialize_Protection), Loc),
8293 Parameter_Associations => Args));
8295 else
8296 Append_To (L,
8297 Make_Procedure_Call_Statement (Loc,
8298 Name => New_Reference_To (
8299 RTE (RE_Initialize_Protection_Entry), Loc),
8300 Parameter_Associations => Args));
8301 end if;
8303 else
8304 Append_To (L,
8305 Make_Procedure_Call_Statement (Loc,
8306 Name => New_Reference_To (RTE (RE_Initialize_Protection), Loc),
8307 Parameter_Associations => Args));
8308 end if;
8310 if Has_Attach_Handler (Ptyp) then
8312 -- We have a list of N Attach_Handler (ProcI, ExprI),
8313 -- and we have to make the following call:
8314 -- Install_Handlers (_object,
8315 -- ((Expr1, Proc1'access), ...., (ExprN, ProcN'access));
8316 -- or, in the case of Ravenscar:
8317 -- Install_Handlers
8318 -- ((Expr1, Proc1'access), ...., (ExprN, ProcN'access));
8320 declare
8321 Args : constant List_Id := New_List;
8322 Table : constant List_Id := New_List;
8323 Ritem : Node_Id := First_Rep_Item (Ptyp);
8325 begin
8326 if not Restricted then
8327 -- Appends the _object argument
8329 Append_To (Args,
8330 Make_Attribute_Reference (Loc,
8331 Prefix =>
8332 Make_Selected_Component (Loc,
8333 Prefix => Make_Identifier (Loc, Name_uInit),
8334 Selector_Name => Make_Identifier (Loc, Name_uObject)),
8335 Attribute_Name => Name_Unchecked_Access));
8336 end if;
8338 -- Build the Attach_Handler table argument
8340 while Present (Ritem) loop
8341 if Nkind (Ritem) = N_Pragma
8342 and then Chars (Ritem) = Name_Attach_Handler
8343 then
8344 declare
8345 Handler : constant Node_Id :=
8346 First (Pragma_Argument_Associations (Ritem));
8348 Interrupt : constant Node_Id := Next (Handler);
8349 Expr : constant Node_Id := Expression (Interrupt);
8351 begin
8352 Append_To (Table,
8353 Make_Aggregate (Loc, Expressions => New_List (
8354 Unchecked_Convert_To
8355 (RTE (RE_System_Interrupt_Id), Expr),
8356 Make_Attribute_Reference (Loc,
8357 Prefix => Make_Selected_Component (Loc,
8358 Make_Identifier (Loc, Name_uInit),
8359 Duplicate_Subexpr_No_Checks
8360 (Expression (Handler))),
8361 Attribute_Name => Name_Access))));
8362 end;
8363 end if;
8365 Next_Rep_Item (Ritem);
8366 end loop;
8368 -- Append the table argument we just built
8370 Append_To (Args, Make_Aggregate (Loc, Table));
8372 -- Append the Install_Handler call to the statements
8374 Append_To (L,
8375 Make_Procedure_Call_Statement (Loc,
8376 Name => New_Reference_To (RTE (RE_Install_Handlers), Loc),
8377 Parameter_Associations => Args));
8378 end;
8379 end if;
8381 return L;
8382 end Make_Initialize_Protection;
8384 ---------------------------
8385 -- Make_Task_Create_Call --
8386 ---------------------------
8388 function Make_Task_Create_Call (Task_Rec : Entity_Id) return Node_Id is
8389 Loc : constant Source_Ptr := Sloc (Task_Rec);
8390 Name : Node_Id;
8391 Tdef : Node_Id;
8392 Tdec : Node_Id;
8393 Ttyp : Node_Id;
8394 Tnam : Name_Id;
8395 Args : List_Id;
8396 Ecount : Node_Id;
8398 begin
8399 Ttyp := Corresponding_Concurrent_Type (Task_Rec);
8400 Tnam := Chars (Ttyp);
8402 -- Get task declaration. In the case of a task type declaration, this
8403 -- is simply the parent of the task type entity. In the single task
8404 -- declaration, this parent will be the implicit type, and we can find
8405 -- the corresponding single task declaration by searching forward in
8406 -- the declaration list in the tree.
8407 -- ??? I am not sure that the test for N_Single_Task_Declaration
8408 -- is needed here. Nodes of this type should have been removed
8409 -- during semantic analysis.
8411 Tdec := Parent (Ttyp);
8413 while Nkind (Tdec) /= N_Task_Type_Declaration
8414 and then Nkind (Tdec) /= N_Single_Task_Declaration
8415 loop
8416 Next (Tdec);
8417 end loop;
8419 -- Now we can find the task definition from this declaration
8421 Tdef := Task_Definition (Tdec);
8423 -- Build the parameter list for the call. Note that _Init is the name
8424 -- of the formal for the object to be initialized, which is the task
8425 -- value record itself.
8427 Args := New_List;
8429 -- Priority parameter. Set to Unspecified_Priority unless there is a
8430 -- priority pragma, in which case we take the value from the pragma.
8432 if Present (Tdef) and then Has_Priority_Pragma (Tdef) then
8433 Append_To (Args,
8434 Make_Selected_Component (Loc,
8435 Prefix => Make_Identifier (Loc, Name_uInit),
8436 Selector_Name => Make_Identifier (Loc, Name_uPriority)));
8437 else
8438 Append_To (Args,
8439 New_Reference_To (RTE (RE_Unspecified_Priority), Loc));
8440 end if;
8442 -- Optional Stack parameter
8444 if Restricted_Profile then
8446 -- If the stack has been preallocated by the expander then
8447 -- pass its address. Otherwise, pass a null address.
8449 if Preallocated_Stacks_On_Target then
8450 Append_To (Args,
8451 Make_Attribute_Reference (Loc,
8452 Prefix => Make_Selected_Component (Loc,
8453 Prefix => Make_Identifier (Loc, Name_uInit),
8454 Selector_Name =>
8455 Make_Identifier (Loc, Name_uStack)),
8456 Attribute_Name => Name_Address));
8458 else
8459 Append_To (Args,
8460 New_Reference_To (RTE (RE_Null_Address), Loc));
8461 end if;
8462 end if;
8464 -- Size parameter. If no Storage_Size pragma is present, then
8465 -- the size is taken from the taskZ variable for the type, which
8466 -- is either Unspecified_Size, or has been reset by the use of
8467 -- a Storage_Size attribute definition clause. If a pragma is
8468 -- present, then the size is taken from the _Size field of the
8469 -- task value record, which was set from the pragma value.
8471 if Present (Tdef)
8472 and then Has_Storage_Size_Pragma (Tdef)
8473 then
8474 Append_To (Args,
8475 Make_Selected_Component (Loc,
8476 Prefix => Make_Identifier (Loc, Name_uInit),
8477 Selector_Name => Make_Identifier (Loc, Name_uSize)));
8479 else
8480 Append_To (Args,
8481 New_Reference_To (Storage_Size_Variable (Ttyp), Loc));
8482 end if;
8484 -- Task_Info parameter. Set to Unspecified_Task_Info unless there is a
8485 -- Task_Info pragma, in which case we take the value from the pragma.
8487 if Present (Tdef)
8488 and then Has_Task_Info_Pragma (Tdef)
8489 then
8490 Append_To (Args,
8491 Make_Selected_Component (Loc,
8492 Prefix => Make_Identifier (Loc, Name_uInit),
8493 Selector_Name => Make_Identifier (Loc, Name_uTask_Info)));
8495 else
8496 Append_To (Args,
8497 New_Reference_To (RTE (RE_Unspecified_Task_Info), Loc));
8498 end if;
8500 if not Restricted_Profile then
8502 -- Number of entries. This is an expression of the form:
8504 -- n + _Init.a'Length + _Init.a'B'Length + ...
8506 -- where a,b... are the entry family names for the task definition
8508 Ecount := Build_Entry_Count_Expression (
8509 Ttyp,
8510 Component_Items (Component_List (
8511 Type_Definition (Parent (
8512 Corresponding_Record_Type (Ttyp))))),
8513 Loc);
8514 Append_To (Args, Ecount);
8516 -- Master parameter. This is a reference to the _Master parameter of
8517 -- the initialization procedure, except in the case of the pragma
8518 -- Restrictions (No_Task_Hierarchy) where the value is fixed to 3.
8519 -- See comments in System.Tasking.Initialization.Init_RTS for the
8520 -- value 3.
8522 if Restriction_Active (No_Task_Hierarchy) = False then
8523 Append_To (Args, Make_Identifier (Loc, Name_uMaster));
8524 else
8525 Append_To (Args, Make_Integer_Literal (Loc, 3));
8526 end if;
8527 end if;
8529 -- State parameter. This is a pointer to the task body procedure. The
8530 -- required value is obtained by taking the address of the task body
8531 -- procedure and converting it (with an unchecked conversion) to the
8532 -- type required by the task kernel. For further details, see the
8533 -- description of Expand_Task_Body
8535 Append_To (Args,
8536 Unchecked_Convert_To (RTE (RE_Task_Procedure_Access),
8537 Make_Attribute_Reference (Loc,
8538 Prefix =>
8539 New_Occurrence_Of (Get_Task_Body_Procedure (Ttyp), Loc),
8540 Attribute_Name => Name_Address)));
8542 -- Discriminants parameter. This is just the address of the task
8543 -- value record itself (which contains the discriminant values
8545 Append_To (Args,
8546 Make_Attribute_Reference (Loc,
8547 Prefix => Make_Identifier (Loc, Name_uInit),
8548 Attribute_Name => Name_Address));
8550 -- Elaborated parameter. This is an access to the elaboration Boolean
8552 Append_To (Args,
8553 Make_Attribute_Reference (Loc,
8554 Prefix => Make_Identifier (Loc, New_External_Name (Tnam, 'E')),
8555 Attribute_Name => Name_Unchecked_Access));
8557 -- Chain parameter. This is a reference to the _Chain parameter of
8558 -- the initialization procedure.
8560 Append_To (Args, Make_Identifier (Loc, Name_uChain));
8562 -- Task name parameter. Take this from the _Task_Id parameter to the
8563 -- init call unless there is a Task_Name pragma, in which case we take
8564 -- the value from the pragma.
8566 if Present (Tdef)
8567 and then Has_Task_Name_Pragma (Tdef)
8568 then
8569 Append_To (Args,
8570 New_Copy (
8571 Expression (First (
8572 Pragma_Argument_Associations (
8573 Find_Task_Or_Protected_Pragma
8574 (Tdef, Name_Task_Name))))));
8576 else
8577 Append_To (Args, Make_Identifier (Loc, Name_uTask_Name));
8578 end if;
8580 -- Created_Task parameter. This is the _Task_Id field of the task
8581 -- record value
8583 Append_To (Args,
8584 Make_Selected_Component (Loc,
8585 Prefix => Make_Identifier (Loc, Name_uInit),
8586 Selector_Name => Make_Identifier (Loc, Name_uTask_Id)));
8588 if Restricted_Profile then
8589 Name := New_Reference_To (RTE (RE_Create_Restricted_Task), Loc);
8590 else
8591 Name := New_Reference_To (RTE (RE_Create_Task), Loc);
8592 end if;
8594 return Make_Procedure_Call_Statement (Loc,
8595 Name => Name, Parameter_Associations => Args);
8596 end Make_Task_Create_Call;
8598 ------------------------------
8599 -- Next_Protected_Operation --
8600 ------------------------------
8602 function Next_Protected_Operation (N : Node_Id) return Node_Id is
8603 Next_Op : Node_Id;
8605 begin
8606 Next_Op := Next (N);
8608 while Present (Next_Op)
8609 and then Nkind (Next_Op) /= N_Subprogram_Body
8610 and then Nkind (Next_Op) /= N_Entry_Body
8611 loop
8612 Next (Next_Op);
8613 end loop;
8615 return Next_Op;
8616 end Next_Protected_Operation;
8618 ----------------------
8619 -- Set_Discriminals --
8620 ----------------------
8622 procedure Set_Discriminals (Dec : Node_Id) is
8623 D : Entity_Id;
8624 Pdef : Entity_Id;
8625 D_Minal : Entity_Id;
8627 begin
8628 pragma Assert (Nkind (Dec) = N_Protected_Type_Declaration);
8629 Pdef := Defining_Identifier (Dec);
8631 if Has_Discriminants (Pdef) then
8632 D := First_Discriminant (Pdef);
8634 while Present (D) loop
8635 D_Minal :=
8636 Make_Defining_Identifier (Sloc (D),
8637 Chars => New_External_Name (Chars (D), 'D'));
8639 Set_Ekind (D_Minal, E_Constant);
8640 Set_Etype (D_Minal, Etype (D));
8641 Set_Scope (D_Minal, Pdef);
8642 Set_Discriminal (D, D_Minal);
8643 Set_Discriminal_Link (D_Minal, D);
8645 Next_Discriminant (D);
8646 end loop;
8647 end if;
8648 end Set_Discriminals;
8650 -----------------
8651 -- Set_Privals --
8652 -----------------
8654 procedure Set_Privals
8655 (Dec : Node_Id;
8656 Op : Node_Id;
8657 Loc : Source_Ptr)
8659 P_Decl : Node_Id;
8660 P_Id : Entity_Id;
8661 Priv : Entity_Id;
8662 Def : Node_Id;
8663 Body_Ent : Entity_Id;
8664 Prec_Decl : constant Node_Id :=
8665 Parent (Corresponding_Record_Type
8666 (Defining_Identifier (Dec)));
8667 Prec_Def : constant Entity_Id := Type_Definition (Prec_Decl);
8668 Obj_Decl : Node_Id;
8669 P_Subtype : Entity_Id;
8670 Assoc_L : constant Elist_Id := New_Elmt_List;
8671 Op_Id : Entity_Id;
8673 begin
8674 pragma Assert (Nkind (Dec) = N_Protected_Type_Declaration);
8675 pragma Assert
8676 (Nkind (Op) = N_Subprogram_Body or else Nkind (Op) = N_Entry_Body);
8678 Def := Protected_Definition (Dec);
8680 if Present (Private_Declarations (Def)) then
8682 P_Decl := First (Private_Declarations (Def));
8684 while Present (P_Decl) loop
8685 if Nkind (P_Decl) = N_Component_Declaration then
8686 P_Id := Defining_Identifier (P_Decl);
8687 Priv :=
8688 Make_Defining_Identifier (Loc,
8689 New_External_Name (Chars (P_Id), 'P'));
8691 Set_Ekind (Priv, E_Variable);
8692 Set_Etype (Priv, Etype (P_Id));
8693 Set_Scope (Priv, Scope (P_Id));
8694 Set_Esize (Priv, Esize (Etype (P_Id)));
8695 Set_Alignment (Priv, Alignment (Etype (P_Id)));
8697 -- If the type of the component is an itype, we must
8698 -- create a new itype for the corresponding prival in
8699 -- each protected operation, to avoid scoping problems.
8700 -- We create new itypes by copying the tree for the
8701 -- component definition.
8703 if Is_Itype (Etype (P_Id)) then
8704 Append_Elmt (P_Id, Assoc_L);
8705 Append_Elmt (Priv, Assoc_L);
8707 if Nkind (Op) = N_Entry_Body then
8708 Op_Id := Defining_Identifier (Op);
8709 else
8710 Op_Id := Defining_Unit_Name (Specification (Op));
8711 end if;
8713 Discard_Node
8714 (New_Copy_Tree (P_Decl, Assoc_L, New_Scope => Op_Id));
8715 end if;
8717 Set_Protected_Operation (P_Id, Op);
8718 Set_Prival (P_Id, Priv);
8719 end if;
8721 Next (P_Decl);
8722 end loop;
8723 end if;
8725 -- There is one more implicit private declaration: the object
8726 -- itself. A "prival" for this is attached to the protected
8727 -- body defining identifier.
8729 Body_Ent := Corresponding_Body (Dec);
8731 Priv :=
8732 Make_Defining_Identifier (Sloc (Body_Ent),
8733 Chars => New_External_Name (Chars (Body_Ent), 'R'));
8735 -- Set the Etype to the implicit subtype of Protection created when
8736 -- the protected type declaration was expanded. This node will not
8737 -- be analyzed until it is used as the defining identifier for the
8738 -- renaming declaration in the protected operation body, and it will
8739 -- be needed in the references expanded before that body is expanded.
8740 -- Since the Protection field is aliased, set Is_Aliased as well.
8742 Obj_Decl := First (Component_Items (Component_List (Prec_Def)));
8743 while Chars (Defining_Identifier (Obj_Decl)) /= Name_uObject loop
8744 Next (Obj_Decl);
8745 end loop;
8747 P_Subtype := Etype (Defining_Identifier (Obj_Decl));
8748 Set_Ekind (Priv, E_Variable);
8749 Set_Etype (Priv, P_Subtype);
8750 Set_Is_Aliased (Priv);
8751 Set_Object_Ref (Body_Ent, Priv);
8752 end Set_Privals;
8754 ----------------------------
8755 -- Update_Prival_Subtypes --
8756 ----------------------------
8758 procedure Update_Prival_Subtypes (N : Node_Id) is
8760 function Process (N : Node_Id) return Traverse_Result;
8761 -- Update the etype of occurrences of privals whose etype does not
8762 -- match the current Etype of the prival entity itself.
8764 procedure Update_Array_Bounds (E : Entity_Id);
8765 -- Itypes generated for array expressions may depend on the
8766 -- determinants of the protected object, and need to be processed
8767 -- separately because they are not attached to the tree.
8769 procedure Update_Index_Types (N : Node_Id);
8770 -- Similarly, update the types of expressions in indexed components
8771 -- which may depend on other discriminants.
8773 -------------
8774 -- Process --
8775 -------------
8777 function Process (N : Node_Id) return Traverse_Result is
8778 begin
8779 if Is_Entity_Name (N) then
8780 declare
8781 E : constant Entity_Id := Entity (N);
8783 begin
8784 if Present (E)
8785 and then (Ekind (E) = E_Constant
8786 or else Ekind (E) = E_Variable)
8787 and then Nkind (Parent (E)) = N_Object_Renaming_Declaration
8788 and then not Is_Scalar_Type (Etype (E))
8789 and then Etype (N) /= Etype (E)
8790 then
8791 Set_Etype (N, Etype (Entity (Original_Node (N))));
8792 Update_Index_Types (N);
8794 elsif Present (E)
8795 and then Ekind (E) = E_Constant
8796 and then Present (Discriminal_Link (E))
8797 then
8798 Set_Etype (N, Etype (E));
8799 end if;
8800 end;
8802 return OK;
8804 elsif Nkind (N) = N_Defining_Identifier
8805 or else Nkind (N) = N_Defining_Operator_Symbol
8806 or else Nkind (N) = N_Defining_Character_Literal
8807 then
8808 return Skip;
8810 elsif Nkind (N) = N_String_Literal then
8812 -- Array type, but bounds are constant
8814 return OK;
8816 elsif Nkind (N) = N_Object_Declaration
8817 and then Is_Itype (Etype (Defining_Identifier (N)))
8818 and then Is_Array_Type (Etype (Defining_Identifier (N)))
8819 then
8820 Update_Array_Bounds (Etype (Defining_Identifier (N)));
8821 return OK;
8823 -- For array components of discriminated records, use the
8824 -- base type directly, because it may depend indirectly
8825 -- on the discriminants of the protected type. Cleaner would
8826 -- be a systematic mechanism to compute actual subtypes of
8827 -- private components ???
8829 elsif Nkind (N) in N_Has_Etype
8830 and then Present (Etype (N))
8831 and then Is_Array_Type (Etype (N))
8832 and then Nkind (N) = N_Selected_Component
8833 and then Has_Discriminants (Etype (Prefix (N)))
8834 then
8835 Set_Etype (N, Base_Type (Etype (N)));
8836 Update_Index_Types (N);
8837 return OK;
8839 else
8840 if Nkind (N) in N_Has_Etype
8841 and then Present (Etype (N))
8842 and then Is_Itype (Etype (N)) then
8844 if Is_Array_Type (Etype (N)) then
8845 Update_Array_Bounds (Etype (N));
8847 elsif Is_Scalar_Type (Etype (N)) then
8848 Update_Prival_Subtypes (Type_Low_Bound (Etype (N)));
8849 Update_Prival_Subtypes (Type_High_Bound (Etype (N)));
8850 end if;
8851 end if;
8853 return OK;
8854 end if;
8855 end Process;
8857 -------------------------
8858 -- Update_Array_Bounds --
8859 -------------------------
8861 procedure Update_Array_Bounds (E : Entity_Id) is
8862 Ind : Node_Id;
8864 begin
8865 Ind := First_Index (E);
8867 while Present (Ind) loop
8868 Update_Prival_Subtypes (Type_Low_Bound (Etype (Ind)));
8869 Update_Prival_Subtypes (Type_High_Bound (Etype (Ind)));
8870 Next_Index (Ind);
8871 end loop;
8872 end Update_Array_Bounds;
8874 ------------------------
8875 -- Update_Index_Types --
8876 ------------------------
8878 procedure Update_Index_Types (N : Node_Id) is
8879 Indx1 : Node_Id;
8880 I_Typ : Node_Id;
8881 begin
8882 -- If the prefix has an actual subtype that is different
8883 -- from the nominal one, update the types of the indices,
8884 -- so that the proper constraints are applied. Do not
8885 -- apply this transformation to a packed array, where the
8886 -- index type is computed for a byte array and is different
8887 -- from the source index.
8889 if Nkind (Parent (N)) = N_Indexed_Component
8890 and then
8891 not Is_Bit_Packed_Array (Etype (Prefix (Parent (N))))
8892 then
8893 Indx1 := First (Expressions (Parent (N)));
8894 I_Typ := First_Index (Etype (N));
8896 while Present (Indx1) and then Present (I_Typ) loop
8898 if not Is_Entity_Name (Indx1) then
8899 Set_Etype (Indx1, Base_Type (Etype (I_Typ)));
8900 end if;
8902 Next (Indx1);
8903 Next_Index (I_Typ);
8904 end loop;
8905 end if;
8906 end Update_Index_Types;
8908 procedure Traverse is new Traverse_Proc;
8910 -- Start of processing for Update_Prival_Subtypes
8912 begin
8913 Traverse (N);
8914 end Update_Prival_Subtypes;
8916 end Exp_Ch9;