1 /******************************************************************************
2 *
3 * Module Name: aslmethod.c - Control method analysis walk
4 *
5 *****************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2013, 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
45 #include "aslcompiler.h"
46 #include "aslcompiler.y.h"
47 #include "acparser.h"
48 #include "amlcode.h"
49
50
51 #define _COMPONENT ACPI_COMPILER
52 ACPI_MODULE_NAME ("aslmethod")
53
54
55 /* Local prototypes */
56
57 void
58 MtCheckNamedObjectInMethod (
59 ACPI_PARSE_OBJECT *Op,
60 ASL_METHOD_INFO *MethodInfo);
61
62
63 /*******************************************************************************
64 *
65 * FUNCTION: MtMethodAnalysisWalkBegin
66 *
67 * PARAMETERS: ASL_WALK_CALLBACK
68 *
69 * RETURN: Status
70 *
71 * DESCRIPTION: Descending callback for the analysis walk. Check methods for:
72 * 1) Initialized local variables
73 * 2) Valid arguments
74 * 3) Return types
75 *
76 ******************************************************************************/
77
78 ACPI_STATUS
79 MtMethodAnalysisWalkBegin (
80 ACPI_PARSE_OBJECT *Op,
81 UINT32 Level,
82 void *Context)
83 {
84 ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
85 ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
86 ACPI_PARSE_OBJECT *Next;
87 UINT32 RegisterNumber;
88 UINT32 i;
89 char LocalName[] = "Local0";
90 char ArgName[] = "Arg0";
91 ACPI_PARSE_OBJECT *ArgNode;
92 ACPI_PARSE_OBJECT *NextType;
93 ACPI_PARSE_OBJECT *NextParamType;
94 UINT8 ActualArgs = 0;
95
96
97 switch (Op->Asl.ParseOpcode)
98 {
99 case PARSEOP_METHOD:
100
101 TotalMethods++;
102
103 /* Create and init method info */
104
105 MethodInfo = UtLocalCalloc (sizeof (ASL_METHOD_INFO));
106 MethodInfo->Next = WalkInfo->MethodStack;
107 MethodInfo->Op = Op;
108
109 WalkInfo->MethodStack = MethodInfo;
110
111 /* Get the name node, ignored here */
112
113 Next = Op->Asl.Child;
114
115 /* Get the NumArguments node */
116
117 Next = Next->Asl.Next;
118 MethodInfo->NumArguments = (UINT8)
119 (((UINT8) Next->Asl.Value.Integer) & 0x07);
120
121 /* Get the SerializeRule and SyncLevel nodes, ignored here */
122
123 Next = Next->Asl.Next;
124 MethodInfo->ShouldBeSerialized = (UINT8) Next->Asl.Value.Integer;
125
126 Next = Next->Asl.Next;
127 ArgNode = Next;
128
129 /* Get the ReturnType node */
130
131 Next = Next->Asl.Next;
132
133 NextType = Next->Asl.Child;
134 while (NextType)
135 {
136 /* Get and map each of the ReturnTypes */
137
138 MethodInfo->ValidReturnTypes |= AnMapObjTypeToBtype (NextType);
139 NextType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
140 NextType = NextType->Asl.Next;
141 }
142
143 /* Get the ParameterType node */
144
145 Next = Next->Asl.Next;
146
147 NextType = Next->Asl.Child;
148 while (NextType)
149 {
150 if (NextType->Asl.ParseOpcode == PARSEOP_DEFAULT_ARG)
151 {
152 NextParamType = NextType->Asl.Child;
153 while (NextParamType)
154 {
155 MethodInfo->ValidArgTypes[ActualArgs] |= AnMapObjTypeToBtype (NextParamType);
156 NextParamType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
157 NextParamType = NextParamType->Asl.Next;
158 }
159 }
160 else
161 {
162 MethodInfo->ValidArgTypes[ActualArgs] =
163 AnMapObjTypeToBtype (NextType);
164 NextType->Asl.ParseOpcode = PARSEOP_DEFAULT_ARG;
165 ActualArgs++;
166 }
167
168 NextType = NextType->Asl.Next;
169 }
170
171 if ((MethodInfo->NumArguments) &&
172 (MethodInfo->NumArguments != ActualArgs))
173 {
174 /* error: Param list did not match number of args */
175 }
176
177 /* Allow numarguments == 0 for Function() */
178
179 if ((!MethodInfo->NumArguments) && (ActualArgs))
180 {
181 MethodInfo->NumArguments = ActualArgs;
182 ArgNode->Asl.Value.Integer |= ActualArgs;
183 }
184
185 /*
186 * Actual arguments are initialized at method entry.
187 * All other ArgX "registers" can be used as locals, so we
188 * track their initialization.
189 */
190 for (i = 0; i < MethodInfo->NumArguments; i++)
191 {
192 MethodInfo->ArgInitialized[i] = TRUE;
193 }
194 break;
195
196 case PARSEOP_METHODCALL:
197
198 if (MethodInfo &&
199 (Op->Asl.Node == MethodInfo->Op->Asl.Node))
200 {
201 AslError (ASL_REMARK, ASL_MSG_RECURSION, Op, Op->Asl.ExternalName);
202 }
203 break;
204
205 case PARSEOP_LOCAL0:
206 case PARSEOP_LOCAL1:
207 case PARSEOP_LOCAL2:
208 case PARSEOP_LOCAL3:
209 case PARSEOP_LOCAL4:
210 case PARSEOP_LOCAL5:
211 case PARSEOP_LOCAL6:
212 case PARSEOP_LOCAL7:
213
214 if (!MethodInfo)
215 {
216 /*
217 * Local was used outside a control method, or there was an error
218 * in the method declaration.
219 */
220 AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD, Op, Op->Asl.ExternalName);
221 return (AE_ERROR);
222 }
223
224 RegisterNumber = (Op->Asl.AmlOpcode & 0x000F);
225
226 /*
227 * If the local is being used as a target, mark the local
228 * initialized
229 */
230 if (Op->Asl.CompileFlags & NODE_IS_TARGET)
231 {
232 MethodInfo->LocalInitialized[RegisterNumber] = TRUE;
233 }
234
235 /*
236 * Otherwise, this is a reference, check if the local
237 * has been previously initialized.
238 *
239 * The only operator that accepts an uninitialized value is ObjectType()
240 */
241 else if ((!MethodInfo->LocalInitialized[RegisterNumber]) &&
242 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
243 {
244 LocalName[strlen (LocalName) -1] = (char) (RegisterNumber + 0x30);
245 AslError (ASL_ERROR, ASL_MSG_LOCAL_INIT, Op, LocalName);
246 }
247 break;
248
249 case PARSEOP_ARG0:
250 case PARSEOP_ARG1:
251 case PARSEOP_ARG2:
252 case PARSEOP_ARG3:
253 case PARSEOP_ARG4:
254 case PARSEOP_ARG5:
255 case PARSEOP_ARG6:
256
257 if (!MethodInfo)
258 {
259 /*
260 * Arg was used outside a control method, or there was an error
261 * in the method declaration.
262 */
263 AslError (ASL_REMARK, ASL_MSG_LOCAL_OUTSIDE_METHOD, Op, Op->Asl.ExternalName);
264 return (AE_ERROR);
265 }
266
267 RegisterNumber = (Op->Asl.AmlOpcode & 0x000F) - 8;
268 ArgName[strlen (ArgName) -1] = (char) (RegisterNumber + 0x30);
269
270 /*
271 * If the Arg is being used as a target, mark the local
272 * initialized
273 */
274 if (Op->Asl.CompileFlags & NODE_IS_TARGET)
275 {
276 MethodInfo->ArgInitialized[RegisterNumber] = TRUE;
277 }
278
279 /*
280 * Otherwise, this is a reference, check if the Arg
281 * has been previously initialized.
282 *
283 * The only operator that accepts an uninitialized value is ObjectType()
284 */
285 else if ((!MethodInfo->ArgInitialized[RegisterNumber]) &&
286 (Op->Asl.Parent->Asl.ParseOpcode != PARSEOP_OBJECTTYPE))
287 {
288 AslError (ASL_ERROR, ASL_MSG_ARG_INIT, Op, ArgName);
289 }
290
291 /* Flag this arg if it is not a "real" argument to the method */
292
293 if (RegisterNumber >= MethodInfo->NumArguments)
294 {
295 AslError (ASL_REMARK, ASL_MSG_NOT_PARAMETER, Op, ArgName);
296 }
297 break;
298
299 case PARSEOP_RETURN:
300
301 if (!MethodInfo)
302 {
303 /*
304 * Probably was an error in the method declaration,
305 * no additional error here
306 */
307 ACPI_WARNING ((AE_INFO, "%p, No parent method", Op));
308 return (AE_ERROR);
309 }
310
311 /*
312 * A child indicates a possible return value. A simple Return or
313 * Return() is marked with NODE_IS_NULL_RETURN by the parser so
314 * that it is not counted as a "real" return-with-value, although
315 * the AML code that is actually emitted is Return(0). The AML
316 * definition of Return has a required parameter, so we are
317 * forced to convert a null return to Return(0).
318 */
319 if ((Op->Asl.Child) &&
320 (Op->Asl.Child->Asl.ParseOpcode != PARSEOP_DEFAULT_ARG) &&
321 (!(Op->Asl.Child->Asl.CompileFlags & NODE_IS_NULL_RETURN)))
322 {
323 MethodInfo->NumReturnWithValue++;
324 }
325 else
326 {
327 MethodInfo->NumReturnNoValue++;
328 }
329 break;
330
331 case PARSEOP_BREAK:
332 case PARSEOP_CONTINUE:
333
334 Next = Op->Asl.Parent;
335 while (Next)
336 {
337 if (Next->Asl.ParseOpcode == PARSEOP_WHILE)
338 {
339 break;
340 }
341 Next = Next->Asl.Parent;
342 }
343
344 if (!Next)
345 {
346 AslError (ASL_ERROR, ASL_MSG_NO_WHILE, Op, NULL);
347 }
348 break;
349
350 case PARSEOP_STALL:
351
352 /* We can range check if the argument is an integer */
353
354 if ((Op->Asl.Child->Asl.ParseOpcode == PARSEOP_INTEGER) &&
355 (Op->Asl.Child->Asl.Value.Integer > ACPI_UINT8_MAX))
356 {
357 AslError (ASL_ERROR, ASL_MSG_INVALID_TIME, Op, NULL);
358 }
359 break;
360
361 case PARSEOP_DEVICE:
362 case PARSEOP_EVENT:
363 case PARSEOP_MUTEX:
364 case PARSEOP_OPERATIONREGION:
365 case PARSEOP_POWERRESOURCE:
366 case PARSEOP_PROCESSOR:
367 case PARSEOP_THERMALZONE:
368
369 /*
370 * The first operand is a name to be created in the namespace.
371 * Check against the reserved list.
372 */
373 i = ApCheckForPredefinedName (Op, Op->Asl.NameSeg);
374 if (i < ACPI_VALID_RESERVED_NAME_MAX)
375 {
376 AslError (ASL_ERROR, ASL_MSG_RESERVED_USE, Op, Op->Asl.ExternalName);
377 }
378 break;
379
380 case PARSEOP_NAME:
381
382 /* Typecheck any predefined names statically defined with Name() */
383
384 ApCheckForPredefinedObject (Op, Op->Asl.NameSeg);
385
386 /* Special typechecking for _HID */
387
388 if (!ACPI_STRCMP (METHOD_NAME__HID, Op->Asl.NameSeg))
389 {
390 Next = Op->Asl.Child->Asl.Next;
391 AnCheckId (Next, ASL_TYPE_HID);
392 }
393
394 /* Special typechecking for _CID */
395
396 else if (!ACPI_STRCMP (METHOD_NAME__CID, Op->Asl.NameSeg))
397 {
398 Next = Op->Asl.Child->Asl.Next;
399
400 if ((Next->Asl.ParseOpcode == PARSEOP_PACKAGE) ||
401 (Next->Asl.ParseOpcode == PARSEOP_VAR_PACKAGE))
402 {
403 Next = Next->Asl.Child;
404 while (Next)
405 {
406 AnCheckId (Next, ASL_TYPE_CID);
407 Next = Next->Asl.Next;
408 }
409 }
410 else
411 {
412 AnCheckId (Next, ASL_TYPE_CID);
413 }
414 }
415 break;
416
417 default:
418
419 break;
420 }
421
422 /* Check for named object creation within a non-serialized method */
423
424 MtCheckNamedObjectInMethod (Op, MethodInfo);
425 return (AE_OK);
426 }
427
428
429 /*******************************************************************************
430 *
431 * FUNCTION: MtCheckNamedObjectInMethod
432 *
433 * PARAMETERS: Op - Current parser op
434 * MethodInfo - Info for method being parsed
435 *
436 * RETURN: None
437 *
438 * DESCRIPTION: Detect if a non-serialized method is creating a named object,
439 * which could possibly cause problems if two threads execute
440 * the method concurrently. Emit a remark in this case.
441 *
442 ******************************************************************************/
443
444 void
445 MtCheckNamedObjectInMethod (
446 ACPI_PARSE_OBJECT *Op,
447 ASL_METHOD_INFO *MethodInfo)
448 {
449 const ACPI_OPCODE_INFO *OpInfo;
450
451
452 /* We don't care about actual method declarations */
453
454 if (Op->Asl.AmlOpcode == AML_METHOD_OP)
455 {
456 return;
457 }
458
459 /* Determine if we are creating a named object */
460
461 OpInfo = AcpiPsGetOpcodeInfo (Op->Asl.AmlOpcode);
462 if (OpInfo->Class == AML_CLASS_NAMED_OBJECT)
463 {
464 /*
465 * If we have a named object created within a non-serialized method,
466 * emit a remark that the method should be serialized.
467 *
468 * Reason: If a thread blocks within the method for any reason, and
469 * another thread enters the method, the method will fail because an
470 * attempt will be made to create the same object twice.
471 */
472 if (MethodInfo && !MethodInfo->ShouldBeSerialized)
473 {
474 AslError (ASL_REMARK, ASL_MSG_SERIALIZED_REQUIRED, MethodInfo->Op,
475 "due to creation of named objects within");
476
477 /* Emit message only ONCE per method */
478
479 MethodInfo->ShouldBeSerialized = TRUE;
480 }
481 }
482 }
483
484
485 /*******************************************************************************
486 *
487 * FUNCTION: MtMethodAnalysisWalkEnd
488 *
489 * PARAMETERS: ASL_WALK_CALLBACK
490 *
491 * RETURN: Status
492 *
493 * DESCRIPTION: Ascending callback for analysis walk. Complete method
494 * return analysis.
495 *
496 ******************************************************************************/
497
498 ACPI_STATUS
499 MtMethodAnalysisWalkEnd (
500 ACPI_PARSE_OBJECT *Op,
501 UINT32 Level,
502 void *Context)
503 {
504 ASL_ANALYSIS_WALK_INFO *WalkInfo = (ASL_ANALYSIS_WALK_INFO *) Context;
505 ASL_METHOD_INFO *MethodInfo = WalkInfo->MethodStack;
506
507
508 switch (Op->Asl.ParseOpcode)
509 {
510 case PARSEOP_METHOD:
511 case PARSEOP_RETURN:
512
513 if (!MethodInfo)
514 {
515 printf ("No method info for method! [%s]\n", Op->Asl.Namepath);
516 AslError (ASL_ERROR, ASL_MSG_COMPILER_INTERNAL, Op,
517 "No method info for this method");
518
519 CmCleanupAndExit ();
520 return (AE_AML_INTERNAL);
521 }
522 break;
523
524 default:
525
526 break;
527 }
528
529 switch (Op->Asl.ParseOpcode)
530 {
531 case PARSEOP_METHOD:
532
533 WalkInfo->MethodStack = MethodInfo->Next;
534
535 /*
536 * Check if there is no return statement at the end of the
537 * method AND we can actually get there -- i.e., the execution
538 * of the method can possibly terminate without a return statement.
539 */
540 if ((!AnLastStatementIsReturn (Op)) &&
541 (!(Op->Asl.CompileFlags & NODE_HAS_NO_EXIT)))
542 {
543 /*
544 * No return statement, and execution can possibly exit
545 * via this path. This is equivalent to Return ()
546 */
547 MethodInfo->NumReturnNoValue++;
548 }
549
550 /*
551 * Check for case where some return statements have a return value
552 * and some do not. Exit without a return statement is a return with
553 * no value
554 */
555 if (MethodInfo->NumReturnNoValue &&
556 MethodInfo->NumReturnWithValue)
557 {
558 AslError (ASL_WARNING, ASL_MSG_RETURN_TYPES, Op,
559 Op->Asl.ExternalName);
560 }
561
562 /*
563 * If there are any RETURN() statements with no value, or there is a
564 * control path that allows the method to exit without a return value,
565 * we mark the method as a method that does not return a value. This
566 * knowledge can be used to check method invocations that expect a
567 * returned value.
568 */
569 if (MethodInfo->NumReturnNoValue)
570 {
571 if (MethodInfo->NumReturnWithValue)
572 {
573 Op->Asl.CompileFlags |= NODE_METHOD_SOME_NO_RETVAL;
574 }
575 else
576 {
577 Op->Asl.CompileFlags |= NODE_METHOD_NO_RETVAL;
578 }
579 }
580
581 /*
582 * Check predefined method names for correct return behavior
583 * and correct number of arguments. Also, some special checks
584 * For GPE and _REG methods.
585 */
586 if (ApCheckForPredefinedMethod (Op, MethodInfo))
587 {
588 /* Special check for two names like _L01 and _E01 in same scope */
589
590 ApCheckForGpeNameConflict (Op);
591
592 /*
593 * Special check for _REG: Must have an operation region definition
594 * within the same scope!
595 */
596 ApCheckRegMethod (Op);
597 }
598
599 ACPI_FREE (MethodInfo);
600 break;
601
602 case PARSEOP_NAME:
603
604 /* Special check for two names like _L01 and _E01 in same scope */
605
606 ApCheckForGpeNameConflict (Op);
607 break;
608
609 case PARSEOP_RETURN:
610
611 /*
612 * If the parent is a predefined method name, attempt to typecheck
613 * the return value. Only static types can be validated.
614 */
615 ApCheckPredefinedReturnValue (Op, MethodInfo);
616
617 /*
618 * The parent block does not "exit" and continue execution -- the
619 * method is terminated here with the Return() statement.
620 */
621 Op->Asl.Parent->Asl.CompileFlags |= NODE_HAS_NO_EXIT;
622
623 /* Used in the "typing" pass later */
624
625 Op->Asl.ParentMethod = MethodInfo->Op;
626
627 /*
628 * If there is a peer node after the return statement, then this
629 * node is unreachable code -- i.e., it won't be executed because of
630 * the preceding Return() statement.
631 */
632 if (Op->Asl.Next)
633 {
634 AslError (ASL_WARNING, ASL_MSG_UNREACHABLE_CODE, Op->Asl.Next, NULL);
635 }
636 break;
637
638 case PARSEOP_IF:
639
640 if ((Op->Asl.CompileFlags & NODE_HAS_NO_EXIT) &&
641 (Op->Asl.Next) &&
642 (Op->Asl.Next->Asl.ParseOpcode == PARSEOP_ELSE))
643 {
644 /*
645 * This IF has a corresponding ELSE. The IF block has no exit,
646 * (it contains an unconditional Return)
647 * mark the ELSE block to remember this fact.
648 */
649 Op->Asl.Next->Asl.CompileFlags |= NODE_IF_HAS_NO_EXIT;
650 }
651 break;
652
653 case PARSEOP_ELSE:
654
655 if ((Op->Asl.CompileFlags & NODE_HAS_NO_EXIT) &&
656 (Op->Asl.CompileFlags & NODE_IF_HAS_NO_EXIT))
657 {
658 /*
659 * This ELSE block has no exit and the corresponding IF block
660 * has no exit either. Therefore, the parent node has no exit.
661 */
662 Op->Asl.Parent->Asl.CompileFlags |= NODE_HAS_NO_EXIT;
663 }
664 break;
665
666
667 default:
668
669 if ((Op->Asl.CompileFlags & NODE_HAS_NO_EXIT) &&
670 (Op->Asl.Parent))
671 {
672 /* If this node has no exit, then the parent has no exit either */
673
674 Op->Asl.Parent->Asl.CompileFlags |= NODE_HAS_NO_EXIT;
675 }
676 break;
677 }
678
679 return (AE_OK);
680 }