1 /******************************************************************************
2 *
3 * Module Name: aslmethod.c - Control method analysis walk
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2016, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44 #include "aslcompiler.h"
45 #include "aslcompiler.y.h"
46 #include "acparser.h"
47 #include "amlcode.h"
48
49
50 #define _COMPONENT ACPI_COMPILER
51 ACPI_MODULE_NAME ("aslmethod")
52
53
54 /* Local prototypes */
55
56 static void
57 MtCheckNamedObjectInMethod (
58 ACPI_PARSE_OBJECT *Op,
59 ASL_METHOD_INFO *MethodInfo);
60
61
62 /*******************************************************************************
63 *
64 * FUNCTION: MtMethodAnalysisWalkBegin
65 *
66 * PARAMETERS: ASL_WALK_CALLBACK
67 *
68 * RETURN: Status
69 *
70 * DESCRIPTION: Descending callback for the analysis walk. Check methods for:
71 * 1) Initialized local variables
72 * 2) Valid arguments
73 * 3) Return types
74 *
75 ******************************************************************************/
76
77 ACPI_STATUS
MtMethodAnalysisWalkBegin(ACPI_PARSE_OBJECT * Op,UINT32 Level,void * Context)78 MtMethodAnalysisWalkBegin (
79 ACPI_PARSE_OBJECT *Op,
80 UINT32 Level,
81 void *Context)
82 {
83 ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
84 ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
85 ACPI_PARSE_OBJECT *Next;
86 UINT32 RegisterNumber;
87 UINT32 i;
88 char LocalName[] = "Local0";
89 char ArgName[] = "Arg0";
90 ACPI_PARSE_OBJECT *ArgNode;
91 ACPI_PARSE_OBJECT *NextType;
92 ACPI_PARSE_OBJECT *NextParamType;
93 UINT8 ActualArgs = 0;
94
95
96 /* Build cross-reference output file if requested */
97
98 if (Gbl_CrossReferenceOutput)
99 {
100 OtXrefWalkPart1 (Op, Level, MethodInfo);
101 }
102
103 switch (Op->Asl.ParseOpcode)
104 {
105 case PARSEOP_METHOD:
106
107 TotalMethods++;
108
109 /* Create and init method info */
110
111 MethodInfo = UtLocalCalloc (sizeof (ASL_METHOD_INFO));
112 MethodInfo->Next = WalkInfo->MethodStack;
113 MethodInfo->Op = Op;
114
115 WalkInfo->MethodStack = MethodInfo;
116
117 /*
118 * Special handling for _PSx methods. Dependency rules (same scope):
119 *
120 * 1) _PS0 - One of these must exist: _PS1, _PS2, _PS3
121 * 2) _PS1/_PS2/_PS3: A _PS0 must exist
122 */
123 if (ACPI_COMPARE_NAME (METHOD_NAME__PS0, Op->Asl.NameSeg))
124 {
125 /* For _PS0, one of _PS1/_PS2/_PS3 must exist */
126
127 if ((!ApFindNameInScope (METHOD_NAME__PS1, Op)) &&
128 (!ApFindNameInScope (METHOD_NAME__PS2, Op)) &&
129 (!ApFindNameInScope (METHOD_NAME__PS3, Op)))
130 {
131 AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
132 "_PS0 requires one of _PS1/_PS2/_PS3 in same scope");
133 }
134 }
135 else if (
136 ACPI_COMPARE_NAME (METHOD_NAME__PS1, Op->Asl.NameSeg) ||
137 ACPI_COMPARE_NAME (METHOD_NAME__PS2, Op->Asl.NameSeg) ||
138 ACPI_COMPARE_NAME (METHOD_NAME__PS3, Op->Asl.NameSeg))
139 {
140 /* For _PS1/_PS2/_PS3, a _PS0 must exist */
141
142 if (!ApFindNameInScope (METHOD_NAME__PS0, Op))
143 {
144 sprintf (MsgBuffer,
145 "%4.4s requires _PS0 in same scope", Op->Asl.NameSeg);
146
147 AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
148 MsgBuffer);
149 }
150 }
151
152 /* Get the name node */
153
154 Next = Op->Asl.Child;
155
156 /* Get the NumArguments node */
157
158 Next = Next->Asl.Next;
159 MethodInfo->NumArguments = (UINT8)
160 (((UINT8) Next->Asl.Value.Integer) & 0x07);
161
162 /* Get the SerializeRule and SyncLevel nodes, ignored here */
163
164 Next = Next->Asl.Next;
165 MethodInfo->ShouldBeSerialized = (UINT8) Next->Asl.Value.Integer;
166
167 Next = Next->Asl.Next;
168 ArgNode = Next;
169
170 /* Get the ReturnType node */
171
172 Next = Next->Asl.Next;
173
174 NextType = Next->Asl.Child;
175 while (NextType)
176 {
177 /* Get and map each of the ReturnTypes */
178
179 MethodInfo->ValidReturnTypes |= AnMapObjTypeToBtype (NextType);
180 NextType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
181 NextType = NextType->Asl.Next;
182 }
183
184 /* Get the ParameterType node */
185
186 Next = Next->Asl.Next;
187
188 NextType = Next->Asl.Child;
189 while (NextType)
190 {
191 if (NextType->Asl.ParseOpcode == PARSEOP_DEFAULT_ARG)
192 {
193 NextParamType = NextType->Asl.Child;
194 while (NextParamType)
195 {
196 MethodInfo->ValidArgTypes[ActualArgs] |=
197 AnMapObjTypeToBtype (NextParamType);
198
199 NextParamType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
200 NextParamType = NextParamType->Asl.Next;
201 }
202 }
203 else
204 {
205 MethodInfo->ValidArgTypes[ActualArgs] =
206 AnMapObjTypeToBtype (NextType);
207
208 NextType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
209 ActualArgs++;
210 }
211
212 NextType = NextType->Asl.Next;
213 }
214
215 if ((MethodInfo->NumArguments) &&
216 (MethodInfo->NumArguments != ActualArgs))
217 {
218 /* error: Param list did not match number of args */
219 }
220
221 /* Allow numarguments == 0 for Function() */
222
223 if ((!MethodInfo->NumArguments) && (ActualArgs))
224 {
225 MethodInfo->NumArguments = ActualArgs;
226 ArgNode->Asl.Value.Integer |= ActualArgs;
227 }
228
229 /*
230 * Actual arguments are initialized at method entry.
231 * All other ArgX "registers" can be used as locals, so we
232 * track their initialization.
233 */
234 for (i = 0; i < MethodInfo->NumArguments; i++)
235 {
236 MethodInfo->ArgInitialized[i] = TRUE;
237 }
238 break;
239
240 case PARSEOP_METHODCALL:
241
242 if (MethodInfo &&
243 (Op->Asl.Node == MethodInfo->Op->Asl.Node))
244 {
245 AslError (ASL_REMARK, ASL_MSG_RECURSION, Op, Op->Asl.ExternalName);
246 }
247 break;
248
249 case PARSEOP_LOCAL0:
250 case PARSEOP_LOCAL1:
251 case PARSEOP_LOCAL2:
252 case PARSEOP_LOCAL3:
253 case PARSEOP_LOCAL4:
254 case PARSEOP_LOCAL5:
255 case PARSEOP_LOCAL6:
256 case PARSEOP_LOCAL7:
257
258 if (!MethodInfo)
259 {
260 /*
261 * Local was used outside a control method, or there was an error
262 * in the method declaration.
263 */
264 AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD,
265 Op, Op->Asl.ExternalName);
266 return (AE_ERROR);
267 }
268
269 RegisterNumber = (Op->Asl.AmlOpcode & 0x0007);
270
271 /*
272 * If the local is being used as a target, mark the local
273 * initialized
274 */
275 if (Op->Asl.CompileFlags & NODE_IS_TARGET)
276 {
277 MethodInfo->LocalInitialized[RegisterNumber] = TRUE;
278 }
279
280 /*
281 * Otherwise, this is a reference, check if the local
282 * has been previously initialized.
283 *
284 * The only operator that accepts an uninitialized value is ObjectType()
285 */
286 else if ((!MethodInfo->LocalInitialized[RegisterNumber]) &&
287 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
288 {
289 LocalName[strlen (LocalName) -1] = (char) (RegisterNumber + 0x30);
290 AslError (ASL_ERROR, ASL_MSG_LOCAL_INIT, Op, LocalName);
291 }
292 break;
293
294 case PARSEOP_ARG0:
295 case PARSEOP_ARG1:
296 case PARSEOP_ARG2:
297 case PARSEOP_ARG3:
298 case PARSEOP_ARG4:
299 case PARSEOP_ARG5:
300 case PARSEOP_ARG6:
301
302 if (!MethodInfo)
303 {
304 /*
305 * Arg was used outside a control method, or there was an error
306 * in the method declaration.
307 */
308 AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD,
309 Op, Op->Asl.ExternalName);
310 return (AE_ERROR);
311 }
312
313 RegisterNumber = (Op->Asl.AmlOpcode & 0x000F) - 8;
314 ArgName[strlen (ArgName) -1] = (char) (RegisterNumber + 0x30);
315
316 /*
317 * If the Arg is being used as a target, mark the local
318 * initialized
319 */
320 if (Op->Asl.CompileFlags & NODE_IS_TARGET)
321 {
322 MethodInfo->ArgInitialized[RegisterNumber] = TRUE;
323 }
324
325 /*
326 * Otherwise, this is a reference, check if the Arg
327 * has been previously initialized.
328 *
329 * The only operator that accepts an uninitialized value is ObjectType()
330 */
331 else if ((!MethodInfo->ArgInitialized[RegisterNumber]) &&
332 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
333 {
334 AslError (ASL_ERROR, ASL_MSG_ARG_INIT, Op, ArgName);
335 }
336
337 /* Flag this arg if it is not a "real" argument to the method */
338
339 if (RegisterNumber >= MethodInfo->NumArguments)
340 {
341 AslError (ASL_REMARK, ASL_MSG_NOT_PARAMETER, Op, ArgName);
342 }
343 break;
344
345 case PARSEOP_RETURN:
346
347 if (!MethodInfo)
348 {
349 /*
350 * Probably was an error in the method declaration,
351 * no additional error here
352 */
353 ACPI_WARNING ((AE_INFO, "%p, No parent method", Op));
354 return (AE_ERROR);
355 }
356
357 /*
358 * A child indicates a possible return value. A simple Return or
359 * Return() is marked with NODE_IS_NULL_RETURN by the parser so
360 * that it is not counted as a "real" return-with-value, although
361 * the AML code that is actually emitted is Return(0). The AML
362 * definition of Return has a required parameter, so we are
363 * forced to convert a null return to Return(0).
364 */
365 if ((Op->Asl.Child) &&
366 (Op->Asl.Child->Asl.ParseOpcode != PARSEOP_DEFAULT_ARG) &&
367 (!(Op->Asl.Child->Asl.CompileFlags & NODE_IS_NULL_RETURN)))
368 {
369 MethodInfo->NumReturnWithValue++;
370 }
371 else
372 {
373 MethodInfo->NumReturnNoValue++;
374 }
375 break;
376
377 case PARSEOP_BREAK:
378 case PARSEOP_CONTINUE:
379
380 Next = Op->Asl.Parent;
381 while (Next)
382 {
383 if (Next->Asl.ParseOpcode == PARSEOP_WHILE)
384 {
385 break;
386 }
387 Next = Next->Asl.Parent;
388 }
389
390 if (!Next)
391 {
392 AslError (ASL_ERROR, ASL_MSG_NO_WHILE, Op, NULL);
393 }
394 break;
395
396 case PARSEOP_STALL:
397
398 /* We can range check if the argument is an integer */
399
400 if ((Op->Asl.Child->Asl.ParseOpcode == PARSEOP_INTEGER) &&
401 (Op->Asl.Child->Asl.Value.Integer > ACPI_UINT8_MAX))
402 {
403 AslError (ASL_ERROR, ASL_MSG_INVALID_TIME, Op, NULL);
404 }
405 break;
406
407 case PARSEOP_DEVICE:
408
409 if (!ApFindNameInDeviceTree (METHOD_NAME__HID, Op) &&
410 !ApFindNameInDeviceTree (METHOD_NAME__ADR, Op))
411 {
412 AslError (ASL_WARNING, ASL_MSG_MISSING_DEPENDENCY, Op,
413 "Device object requires a _HID or _ADR in same scope");
414 }
415 break;
416
417 case PARSEOP_EVENT:
418 case PARSEOP_MUTEX:
419 case PARSEOP_OPERATIONREGION:
420 case PARSEOP_POWERRESOURCE:
421 case PARSEOP_PROCESSOR:
422 case PARSEOP_THERMALZONE:
423
424 /*
425 * The first operand is a name to be created in the namespace.
426 * Check against the reserved list.
427 */
428 i = ApCheckForPredefinedName (Op, Op->Asl.NameSeg);
429 if (i < ACPI_VALID_RESERVED_NAME_MAX)
430 {
431 AslError (ASL_ERROR, ASL_MSG_RESERVED_USE,
432 Op, Op->Asl.ExternalName);
433 }
434 break;
435
436 case PARSEOP_NAME:
437
438 /* Typecheck any predefined names statically defined with Name() */
439
440 ApCheckForPredefinedObject (Op, Op->Asl.NameSeg);
441
442 /* Special typechecking for _HID */
443
444 if (!strcmp (METHOD_NAME__HID, Op->Asl.NameSeg))
445 {
446 Next = Op->Asl.Child->Asl.Next;
447 AnCheckId (Next, ASL_TYPE_HID);
448 }
449
450 /* Special typechecking for _CID */
451
452 else if (!strcmp (METHOD_NAME__CID, Op->Asl.NameSeg))
453 {
454 Next = Op->Asl.Child->Asl.Next;
455
456 if ((Next->Asl.ParseOpcode == PARSEOP_PACKAGE) ||
457 (Next->Asl.ParseOpcode == PARSEOP_VAR_PACKAGE))
458 {
459 Next = Next->Asl.Child;
460 while (Next)
461 {
462 AnCheckId (Next, ASL_TYPE_CID);
463 Next = Next->Asl.Next;
464 }
465 }
466 else
467 {
468 AnCheckId (Next, ASL_TYPE_CID);
469 }
470 }
471
472 break;
473
474 default:
475
476 break;
477 }
478
479 /* Check for named object creation within a non-serialized method */
480
481 MtCheckNamedObjectInMethod (Op, MethodInfo);
482 return (AE_OK);
483 }
484
485
486 /*******************************************************************************
487 *
488 * FUNCTION: MtCheckNamedObjectInMethod
489 *
490 * PARAMETERS: Op - Current parser op
491 * MethodInfo - Info for method being parsed
492 *
493 * RETURN: None
494 *
495 * DESCRIPTION: Detect if a non-serialized method is creating a named object,
496 * which could possibly cause problems if two threads execute
497 * the method concurrently. Emit a remark in this case.
498 *
499 ******************************************************************************/
500
501 static void
MtCheckNamedObjectInMethod(ACPI_PARSE_OBJECT * Op,ASL_METHOD_INFO * MethodInfo)502 MtCheckNamedObjectInMethod (
503 ACPI_PARSE_OBJECT *Op,
504 ASL_METHOD_INFO *MethodInfo)
505 {
506 const ACPI_OPCODE_INFO *OpInfo;
507
508
509 /* We don't care about actual method declarations or scopes */
510
511 if ((Op->Asl.AmlOpcode == AML_METHOD_OP) ||
512 (Op->Asl.AmlOpcode == AML_SCOPE_OP))
513 {
514 return;
515 }
516
517 /* Determine if we are creating a named object */
518
519 OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
520 if (OpInfo->Class == AML_CLASS_NAMED_OBJECT)
521 {
522 /*
523 * If we have a named object created within a non-serialized method,
524 * emit a remark that the method should be serialized.
525 *
526 * Reason: If a thread blocks within the method for any reason, and
527 * another thread enters the method, the method will fail because an
528 * attempt will be made to create the same object twice.
529 */
530 if (MethodInfo && !MethodInfo->ShouldBeSerialized)
531 {
532 AslError (ASL_REMARK, ASL_MSG_SERIALIZED_REQUIRED, MethodInfo->Op,
533 "due to creation of named objects within");
534
535 /* Emit message only ONCE per method */
536
537 MethodInfo->ShouldBeSerialized = TRUE;
538 }
539 }
540 }
541
542
543 /*******************************************************************************
544 *
545 * FUNCTION: MtMethodAnalysisWalkEnd
546 *
547 * PARAMETERS: ASL_WALK_CALLBACK
548 *
549 * RETURN: Status
550 *
551 * DESCRIPTION: Ascending callback for analysis walk. Complete method
552 * return analysis.
553 *
554 ******************************************************************************/
555
556 ACPI_STATUS
MtMethodAnalysisWalkEnd(ACPI_PARSE_OBJECT * Op,UINT32 Level,void * Context)557 MtMethodAnalysisWalkEnd (
558 ACPI_PARSE_OBJECT *Op,
559 UINT32 Level,
560 void *Context)
561 {
562 ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
563 ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
564
565
566 switch (Op->Asl.ParseOpcode)
567 {
568 case PARSEOP_METHOD:
569 case PARSEOP_RETURN:
570
571 if (!MethodInfo)
572 {
573 printf ("No method info for method! [%s]\n", Op->Asl.Namepath);
574 AslError (ASL_ERROR, ASL_MSG_COMPILER_INTERNAL, Op,
575 "No method info for this method");
576
577 CmCleanupAndExit ();
578 return (AE_AML_INTERNAL);
579 }
580 break;
581
582 default:
583
584 break;
585 }
586
587 switch (Op->Asl.ParseOpcode)
588 {
589 case PARSEOP_METHOD:
590
591 WalkInfo->MethodStack = MethodInfo->Next;
592
593 /*
594 * Check if there is no return statement at the end of the
595 * method AND we can actually get there -- i.e., the execution
596 * of the method can possibly terminate without a return statement.
597 */
598 if ((!AnLastStatementIsReturn (Op)) &&
599 (!(Op->Asl.CompileFlags & NODE_HAS_NO_EXIT)))
600 {
601 /*
602 * No return statement, and execution can possibly exit
603 * via this path. This is equivalent to Return ()
604 */
605 MethodInfo->NumReturnNoValue++;
606 }
607
608 /*
609 * Check for case where some return statements have a return value
610 * and some do not. Exit without a return statement is a return with
611 * no value
612 */
613 if (MethodInfo->NumReturnNoValue &&
614 MethodInfo->NumReturnWithValue)
615 {
616 AslError (ASL_WARNING, ASL_MSG_RETURN_TYPES, Op,
617 Op->Asl.ExternalName);
618 }
619
620 /*
621 * If there are any RETURN() statements with no value, or there is a
622 * control path that allows the method to exit without a return value,
623 * we mark the method as a method that does not return a value. This
624 * knowledge can be used to check method invocations that expect a
625 * returned value.
626 */
627 if (MethodInfo->NumReturnNoValue)
628 {
629 if (MethodInfo->NumReturnWithValue)
630 {
631 Op->Asl.CompileFlags |= NODE_METHOD_SOME_NO_RETVAL;
632 }
633 else
634 {
635 Op->Asl.CompileFlags |= NODE_METHOD_NO_RETVAL;
636 }
637 }
638
639 /*
640 * Check predefined method names for correct return behavior
641 * and correct number of arguments. Also, some special checks
642 * For GPE and _REG methods.
643 */
644 if (ApCheckForPredefinedMethod (Op, MethodInfo))
645 {
646 /* Special check for two names like _L01 and _E01 in same scope */
647
648 ApCheckForGpeNameConflict (Op);
649
650 /*
651 * Special check for _REG: Must have an operation region definition
652 * within the same scope!
653 */
654 ApCheckRegMethod (Op);
655 }
656
657 ACPI_FREE (MethodInfo);
658 break;
659
660 case PARSEOP_NAME:
661
662 /* Special check for two names like _L01 and _E01 in same scope */
663
664 ApCheckForGpeNameConflict (Op);
665 break;
666
667 case PARSEOP_RETURN:
668
669 /*
670 * If the parent is a predefined method name, attempt to typecheck
671 * the return value. Only static types can be validated.
672 */
673 ApCheckPredefinedReturnValue (Op, MethodInfo);
674
675 /*
676 * The parent block does not "exit" and continue execution -- the
677 * method is terminated here with the Return() statement.
678 */
679 Op->Asl.Parent->Asl.CompileFlags |= NODE_HAS_NO_EXIT;
680
681 /* Used in the "typing" pass later */
682
683 Op->Asl.ParentMethod = MethodInfo->Op;
684
685 /*
686 * If there is a peer node after the return statement, then this
687 * node is unreachable code -- i.e., it won't be executed because of
688 * the preceding Return() statement.
689 */
690 if (Op->Asl.Next)
691 {
692 AslError (ASL_WARNING, ASL_MSG_UNREACHABLE_CODE,
693 Op->Asl.Next, NULL);
694 }
695 break;
696
697 case PARSEOP_IF:
698
699 if ((Op->Asl.CompileFlags & NODE_HAS_NO_EXIT) &&
700 (Op->Asl.Next) &&
701 (Op->Asl.Next->Asl.ParseOpcode == PARSEOP_ELSE))
702 {
703 /*
704 * This IF has a corresponding ELSE. The IF block has no exit,
705 * (it contains an unconditional Return)
706 * mark the ELSE block to remember this fact.
707 */
708 Op->Asl.Next->Asl.CompileFlags |= NODE_IF_HAS_NO_EXIT;
709 }
710 break;
711
712 case PARSEOP_ELSE:
713
714 if ((Op->Asl.CompileFlags & NODE_HAS_NO_EXIT) &&
715 (Op->Asl.CompileFlags & NODE_IF_HAS_NO_EXIT))
716 {
717 /*
718 * This ELSE block has no exit and the corresponding IF block
719 * has no exit either. Therefore, the parent node has no exit.
720 */
721 Op->Asl.Parent->Asl.CompileFlags |= NODE_HAS_NO_EXIT;
722 }
723 break;
724
725
726 default:
727
728 if ((Op->Asl.CompileFlags & NODE_HAS_NO_EXIT) &&
729 (Op->Asl.Parent))
730 {
731 /* If this node has no exit, then the parent has no exit either */
732
733 Op->Asl.Parent->Asl.CompileFlags |= NODE_HAS_NO_EXIT;
734 }
735 break;
736 }
737
738 return (AE_OK);
739 }
740