xref: /titanic_41/usr/src/uts/intel/io/acpica/executer/exresop.c (revision c28afb19581b550bf02e148f953e3b239421e1ee)
1 
2 /******************************************************************************
3  *
4  * Module Name: exresop - AML Interpreter operand/object resolution
5  *
6  *****************************************************************************/
7 
8 /*
9  * Copyright (C) 2000 - 2011, Intel Corp.
10  * All rights reserved.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions, and the following disclaimer,
17  *    without modification.
18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19  *    substantially similar to the "NO WARRANTY" disclaimer below
20  *    ("Disclaimer") and any redistribution must be conditioned upon
21  *    including a substantially similar Disclaimer requirement for further
22  *    binary redistribution.
23  * 3. Neither the names of the above-listed copyright holders nor the names
24  *    of any contributors may be used to endorse or promote products derived
25  *    from this software without specific prior written permission.
26  *
27  * Alternatively, this software may be distributed under the terms of the
28  * GNU General Public License ("GPL") version 2 as published by the Free
29  * Software Foundation.
30  *
31  * NO WARRANTY
32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42  * POSSIBILITY OF SUCH DAMAGES.
43  */
44 
45 #define __EXRESOP_C__
46 
47 #include "acpi.h"
48 #include "accommon.h"
49 #include "amlcode.h"
50 #include "acparser.h"
51 #include "acinterp.h"
52 #include "acnamesp.h"
53 
54 
55 #define _COMPONENT          ACPI_EXECUTER
56         ACPI_MODULE_NAME    ("exresop")
57 
58 /* Local prototypes */
59 
60 static ACPI_STATUS
61 AcpiExCheckObjectType (
62     ACPI_OBJECT_TYPE        TypeNeeded,
63     ACPI_OBJECT_TYPE        ThisType,
64     void                    *Object);
65 
66 
67 /*******************************************************************************
68  *
69  * FUNCTION:    AcpiExCheckObjectType
70  *
71  * PARAMETERS:  TypeNeeded          Object type needed
72  *              ThisType            Actual object type
73  *              Object              Object pointer
74  *
75  * RETURN:      Status
76  *
77  * DESCRIPTION: Check required type against actual type
78  *
79  ******************************************************************************/
80 
81 static ACPI_STATUS
82 AcpiExCheckObjectType (
83     ACPI_OBJECT_TYPE        TypeNeeded,
84     ACPI_OBJECT_TYPE        ThisType,
85     void                    *Object)
86 {
87     ACPI_FUNCTION_ENTRY ();
88 
89 
90     if (TypeNeeded == ACPI_TYPE_ANY)
91     {
92         /* All types OK, so we don't perform any typechecks */
93 
94         return (AE_OK);
95     }
96 
97     if (TypeNeeded == ACPI_TYPE_LOCAL_REFERENCE)
98     {
99         /*
100          * Allow the AML "Constant" opcodes (Zero, One, etc.) to be reference
101          * objects and thus allow them to be targets.  (As per the ACPI
102          * specification, a store to a constant is a noop.)
103          */
104         if ((ThisType == ACPI_TYPE_INTEGER) &&
105             (((ACPI_OPERAND_OBJECT *) Object)->Common.Flags & AOPOBJ_AML_CONSTANT))
106         {
107             return (AE_OK);
108         }
109     }
110 
111     if (TypeNeeded != ThisType)
112     {
113         ACPI_ERROR ((AE_INFO,
114             "Needed type [%s], found [%s] %p",
115             AcpiUtGetTypeName (TypeNeeded),
116             AcpiUtGetTypeName (ThisType), Object));
117 
118         return (AE_AML_OPERAND_TYPE);
119     }
120 
121     return (AE_OK);
122 }
123 
124 
125 /*******************************************************************************
126  *
127  * FUNCTION:    AcpiExResolveOperands
128  *
129  * PARAMETERS:  Opcode              - Opcode being interpreted
130  *              StackPtr            - Pointer to the operand stack to be
131  *                                    resolved
132  *              WalkState           - Current state
133  *
134  * RETURN:      Status
135  *
136  * DESCRIPTION: Convert multiple input operands to the types required by the
137  *              target operator.
138  *
139  *      Each 5-bit group in ArgTypes represents one required
140  *      operand and indicates the required Type. The corresponding operand
141  *      will be converted to the required type if possible, otherwise we
142  *      abort with an exception.
143  *
144  ******************************************************************************/
145 
146 ACPI_STATUS
147 AcpiExResolveOperands (
148     UINT16                  Opcode,
149     ACPI_OPERAND_OBJECT     **StackPtr,
150     ACPI_WALK_STATE         *WalkState)
151 {
152     ACPI_OPERAND_OBJECT     *ObjDesc;
153     ACPI_STATUS             Status = AE_OK;
154     UINT8                   ObjectType;
155     UINT32                  ArgTypes;
156     const ACPI_OPCODE_INFO  *OpInfo;
157     UINT32                  ThisArgType;
158     ACPI_OBJECT_TYPE        TypeNeeded;
159     UINT16                  TargetOp = 0;
160 
161 
162     ACPI_FUNCTION_TRACE_U32 (ExResolveOperands, Opcode);
163 
164 
165     OpInfo = AcpiPsGetOpcodeInfo (Opcode);
166     if (OpInfo->Class == AML_CLASS_UNKNOWN)
167     {
168         return_ACPI_STATUS (AE_AML_BAD_OPCODE);
169     }
170 
171     ArgTypes = OpInfo->RuntimeArgs;
172     if (ArgTypes == ARGI_INVALID_OPCODE)
173     {
174         ACPI_ERROR ((AE_INFO, "Unknown AML opcode 0x%X",
175             Opcode));
176 
177         return_ACPI_STATUS (AE_AML_INTERNAL);
178     }
179 
180     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
181         "Opcode %X [%s] RequiredOperandTypes=%8.8X\n",
182         Opcode, OpInfo->Name, ArgTypes));
183 
184     /*
185      * Normal exit is with (ArgTypes == 0) at end of argument list.
186      * Function will return an exception from within the loop upon
187      * finding an entry which is not (or cannot be converted
188      * to) the required type; if stack underflows; or upon
189      * finding a NULL stack entry (which should not happen).
190      */
191     while (GET_CURRENT_ARG_TYPE (ArgTypes))
192     {
193         if (!StackPtr || !*StackPtr)
194         {
195             ACPI_ERROR ((AE_INFO, "Null stack entry at %p",
196                 StackPtr));
197 
198             return_ACPI_STATUS (AE_AML_INTERNAL);
199         }
200 
201         /* Extract useful items */
202 
203         ObjDesc = *StackPtr;
204 
205         /* Decode the descriptor type */
206 
207         switch (ACPI_GET_DESCRIPTOR_TYPE (ObjDesc))
208         {
209         case ACPI_DESC_TYPE_NAMED:
210 
211             /* Namespace Node */
212 
213             ObjectType = ((ACPI_NAMESPACE_NODE *) ObjDesc)->Type;
214 
215             /*
216              * Resolve an alias object. The construction of these objects
217              * guarantees that there is only one level of alias indirection;
218              * thus, the attached object is always the aliased namespace node
219              */
220             if (ObjectType == ACPI_TYPE_LOCAL_ALIAS)
221             {
222                 ObjDesc = AcpiNsGetAttachedObject ((ACPI_NAMESPACE_NODE *) ObjDesc);
223                 *StackPtr = ObjDesc;
224                 ObjectType = ((ACPI_NAMESPACE_NODE *) ObjDesc)->Type;
225             }
226             break;
227 
228 
229         case ACPI_DESC_TYPE_OPERAND:
230 
231             /* ACPI internal object */
232 
233             ObjectType = ObjDesc->Common.Type;
234 
235             /* Check for bad ACPI_OBJECT_TYPE */
236 
237             if (!AcpiUtValidObjectType (ObjectType))
238             {
239                 ACPI_ERROR ((AE_INFO,
240                     "Bad operand object type [0x%X]", ObjectType));
241 
242                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
243             }
244 
245             if (ObjectType == (UINT8) ACPI_TYPE_LOCAL_REFERENCE)
246             {
247                 /* Validate the Reference */
248 
249                 switch (ObjDesc->Reference.Class)
250                 {
251                 case ACPI_REFCLASS_DEBUG:
252 
253                     TargetOp = AML_DEBUG_OP;
254 
255                     /*lint -fallthrough */
256 
257                 case ACPI_REFCLASS_ARG:
258                 case ACPI_REFCLASS_LOCAL:
259                 case ACPI_REFCLASS_INDEX:
260                 case ACPI_REFCLASS_REFOF:
261                 case ACPI_REFCLASS_TABLE:    /* DdbHandle from LOAD_OP or LOAD_TABLE_OP */
262                 case ACPI_REFCLASS_NAME:     /* Reference to a named object */
263 
264                     ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
265                         "Operand is a Reference, Class [%s] %2.2X\n",
266                         AcpiUtGetReferenceName (ObjDesc),
267                         ObjDesc->Reference.Class));
268                     break;
269 
270                 default:
271 
272                     ACPI_ERROR ((AE_INFO,
273                         "Unknown Reference Class 0x%2.2X in %p",
274                         ObjDesc->Reference.Class, ObjDesc));
275 
276                     return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
277                 }
278             }
279             break;
280 
281 
282         default:
283 
284             /* Invalid descriptor */
285 
286             ACPI_ERROR ((AE_INFO, "Invalid descriptor %p [%s]",
287                 ObjDesc, AcpiUtGetDescriptorName (ObjDesc)));
288 
289             return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
290         }
291 
292         /* Get one argument type, point to the next */
293 
294         ThisArgType = GET_CURRENT_ARG_TYPE (ArgTypes);
295         INCREMENT_ARG_LIST (ArgTypes);
296 
297         /*
298          * Handle cases where the object does not need to be
299          * resolved to a value
300          */
301         switch (ThisArgType)
302         {
303         case ARGI_REF_OR_STRING:        /* Can be a String or Reference */
304 
305             if ((ACPI_GET_DESCRIPTOR_TYPE (ObjDesc) == ACPI_DESC_TYPE_OPERAND) &&
306                 (ObjDesc->Common.Type == ACPI_TYPE_STRING))
307             {
308                 /*
309                  * String found - the string references a named object and
310                  * must be resolved to a node
311                  */
312                 goto NextOperand;
313             }
314 
315             /*
316              * Else not a string - fall through to the normal Reference
317              * case below
318              */
319             /*lint -fallthrough */
320 
321         case ARGI_REFERENCE:            /* References: */
322         case ARGI_INTEGER_REF:
323         case ARGI_OBJECT_REF:
324         case ARGI_DEVICE_REF:
325         case ARGI_TARGETREF:     /* Allows implicit conversion rules before store */
326         case ARGI_FIXED_TARGET:  /* No implicit conversion before store to target */
327         case ARGI_SIMPLE_TARGET: /* Name, Local, or Arg - no implicit conversion  */
328 
329             /*
330              * Need an operand of type ACPI_TYPE_LOCAL_REFERENCE
331              * A Namespace Node is OK as-is
332              */
333             if (ACPI_GET_DESCRIPTOR_TYPE (ObjDesc) == ACPI_DESC_TYPE_NAMED)
334             {
335                 goto NextOperand;
336             }
337 
338             Status = AcpiExCheckObjectType (ACPI_TYPE_LOCAL_REFERENCE,
339                             ObjectType, ObjDesc);
340             if (ACPI_FAILURE (Status))
341             {
342                 return_ACPI_STATUS (Status);
343             }
344             goto NextOperand;
345 
346 
347         case ARGI_DATAREFOBJ:  /* Store operator only */
348 
349             /*
350              * We don't want to resolve IndexOp reference objects during
351              * a store because this would be an implicit DeRefOf operation.
352              * Instead, we just want to store the reference object.
353              * -- All others must be resolved below.
354              */
355             if ((Opcode == AML_STORE_OP) &&
356                 ((*StackPtr)->Common.Type == ACPI_TYPE_LOCAL_REFERENCE) &&
357                 ((*StackPtr)->Reference.Class == ACPI_REFCLASS_INDEX))
358             {
359                 goto NextOperand;
360             }
361             break;
362 
363         default:
364             /* All cases covered above */
365             break;
366         }
367 
368         /*
369          * Resolve this object to a value
370          */
371         Status = AcpiExResolveToValue (StackPtr, WalkState);
372         if (ACPI_FAILURE (Status))
373         {
374             return_ACPI_STATUS (Status);
375         }
376 
377         /* Get the resolved object */
378 
379         ObjDesc = *StackPtr;
380 
381         /*
382          * Check the resulting object (value) type
383          */
384         switch (ThisArgType)
385         {
386         /*
387          * For the simple cases, only one type of resolved object
388          * is allowed
389          */
390         case ARGI_MUTEX:
391 
392             /* Need an operand of type ACPI_TYPE_MUTEX */
393 
394             TypeNeeded = ACPI_TYPE_MUTEX;
395             break;
396 
397         case ARGI_EVENT:
398 
399             /* Need an operand of type ACPI_TYPE_EVENT */
400 
401             TypeNeeded = ACPI_TYPE_EVENT;
402             break;
403 
404         case ARGI_PACKAGE:   /* Package */
405 
406             /* Need an operand of type ACPI_TYPE_PACKAGE */
407 
408             TypeNeeded = ACPI_TYPE_PACKAGE;
409             break;
410 
411         case ARGI_ANYTYPE:
412 
413             /* Any operand type will do */
414 
415             TypeNeeded = ACPI_TYPE_ANY;
416             break;
417 
418         case ARGI_DDBHANDLE:
419 
420             /* Need an operand of type ACPI_TYPE_DDB_HANDLE */
421 
422             TypeNeeded = ACPI_TYPE_LOCAL_REFERENCE;
423             break;
424 
425 
426         /*
427          * The more complex cases allow multiple resolved object types
428          */
429         case ARGI_INTEGER:
430 
431             /*
432              * Need an operand of type ACPI_TYPE_INTEGER,
433              * But we can implicitly convert from a STRING or BUFFER
434              * Aka - "Implicit Source Operand Conversion"
435              */
436             Status = AcpiExConvertToInteger (ObjDesc, StackPtr, 16);
437             if (ACPI_FAILURE (Status))
438             {
439                 if (Status == AE_TYPE)
440                 {
441                     ACPI_ERROR ((AE_INFO,
442                         "Needed [Integer/String/Buffer], found [%s] %p",
443                         AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
444 
445                     return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
446                 }
447 
448                 return_ACPI_STATUS (Status);
449             }
450 
451             if (ObjDesc != *StackPtr)
452             {
453                 AcpiUtRemoveReference (ObjDesc);
454             }
455             goto NextOperand;
456 
457 
458         case ARGI_BUFFER:
459 
460             /*
461              * Need an operand of type ACPI_TYPE_BUFFER,
462              * But we can implicitly convert from a STRING or INTEGER
463              * Aka - "Implicit Source Operand Conversion"
464              */
465             Status = AcpiExConvertToBuffer (ObjDesc, StackPtr);
466             if (ACPI_FAILURE (Status))
467             {
468                 if (Status == AE_TYPE)
469                 {
470                     ACPI_ERROR ((AE_INFO,
471                         "Needed [Integer/String/Buffer], found [%s] %p",
472                         AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
473 
474                     return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
475                 }
476 
477                 return_ACPI_STATUS (Status);
478             }
479 
480             if (ObjDesc != *StackPtr)
481             {
482                 AcpiUtRemoveReference (ObjDesc);
483             }
484             goto NextOperand;
485 
486 
487         case ARGI_STRING:
488 
489             /*
490              * Need an operand of type ACPI_TYPE_STRING,
491              * But we can implicitly convert from a BUFFER or INTEGER
492              * Aka - "Implicit Source Operand Conversion"
493              */
494             Status = AcpiExConvertToString (ObjDesc, StackPtr,
495                         ACPI_IMPLICIT_CONVERT_HEX);
496             if (ACPI_FAILURE (Status))
497             {
498                 if (Status == AE_TYPE)
499                 {
500                     ACPI_ERROR ((AE_INFO,
501                         "Needed [Integer/String/Buffer], found [%s] %p",
502                         AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
503 
504                     return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
505                 }
506 
507                 return_ACPI_STATUS (Status);
508             }
509 
510             if (ObjDesc != *StackPtr)
511             {
512                 AcpiUtRemoveReference (ObjDesc);
513             }
514             goto NextOperand;
515 
516 
517         case ARGI_COMPUTEDATA:
518 
519             /* Need an operand of type INTEGER, STRING or BUFFER */
520 
521             switch (ObjDesc->Common.Type)
522             {
523             case ACPI_TYPE_INTEGER:
524             case ACPI_TYPE_STRING:
525             case ACPI_TYPE_BUFFER:
526 
527                 /* Valid operand */
528                break;
529 
530             default:
531                 ACPI_ERROR ((AE_INFO,
532                     "Needed [Integer/String/Buffer], found [%s] %p",
533                     AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
534 
535                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
536             }
537             goto NextOperand;
538 
539 
540         case ARGI_BUFFER_OR_STRING:
541 
542             /* Need an operand of type STRING or BUFFER */
543 
544             switch (ObjDesc->Common.Type)
545             {
546             case ACPI_TYPE_STRING:
547             case ACPI_TYPE_BUFFER:
548 
549                 /* Valid operand */
550                break;
551 
552             case ACPI_TYPE_INTEGER:
553 
554                 /* Highest priority conversion is to type Buffer */
555 
556                 Status = AcpiExConvertToBuffer (ObjDesc, StackPtr);
557                 if (ACPI_FAILURE (Status))
558                 {
559                     return_ACPI_STATUS (Status);
560                 }
561 
562                 if (ObjDesc != *StackPtr)
563                 {
564                     AcpiUtRemoveReference (ObjDesc);
565                 }
566                 break;
567 
568             default:
569                 ACPI_ERROR ((AE_INFO,
570                     "Needed [Integer/String/Buffer], found [%s] %p",
571                     AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
572 
573                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
574             }
575             goto NextOperand;
576 
577 
578         case ARGI_DATAOBJECT:
579             /*
580              * ARGI_DATAOBJECT is only used by the SizeOf operator.
581              * Need a buffer, string, package, or RefOf reference.
582              *
583              * The only reference allowed here is a direct reference to
584              * a namespace node.
585              */
586             switch (ObjDesc->Common.Type)
587             {
588             case ACPI_TYPE_PACKAGE:
589             case ACPI_TYPE_STRING:
590             case ACPI_TYPE_BUFFER:
591             case ACPI_TYPE_LOCAL_REFERENCE:
592 
593                 /* Valid operand */
594                 break;
595 
596             default:
597                 ACPI_ERROR ((AE_INFO,
598                     "Needed [Buffer/String/Package/Reference], found [%s] %p",
599                     AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
600 
601                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
602             }
603             goto NextOperand;
604 
605 
606         case ARGI_COMPLEXOBJ:
607 
608             /* Need a buffer or package or (ACPI 2.0) String */
609 
610             switch (ObjDesc->Common.Type)
611             {
612             case ACPI_TYPE_PACKAGE:
613             case ACPI_TYPE_STRING:
614             case ACPI_TYPE_BUFFER:
615 
616                 /* Valid operand */
617                 break;
618 
619             default:
620                 ACPI_ERROR ((AE_INFO,
621                     "Needed [Buffer/String/Package], found [%s] %p",
622                     AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
623 
624                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
625             }
626             goto NextOperand;
627 
628 
629         case ARGI_REGION_OR_BUFFER: /* Used by Load() only */
630 
631             /* Need an operand of type REGION or a BUFFER (which could be a resolved region field) */
632 
633             switch (ObjDesc->Common.Type)
634             {
635             case ACPI_TYPE_BUFFER:
636             case ACPI_TYPE_REGION:
637 
638                 /* Valid operand */
639                 break;
640 
641             default:
642                 ACPI_ERROR ((AE_INFO,
643                     "Needed [Region/Buffer], found [%s] %p",
644                     AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
645 
646                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
647             }
648             goto NextOperand;
649 
650 
651         case ARGI_DATAREFOBJ:
652 
653             /* Used by the Store() operator only */
654 
655             switch (ObjDesc->Common.Type)
656             {
657             case ACPI_TYPE_INTEGER:
658             case ACPI_TYPE_PACKAGE:
659             case ACPI_TYPE_STRING:
660             case ACPI_TYPE_BUFFER:
661             case ACPI_TYPE_BUFFER_FIELD:
662             case ACPI_TYPE_LOCAL_REFERENCE:
663             case ACPI_TYPE_LOCAL_REGION_FIELD:
664             case ACPI_TYPE_LOCAL_BANK_FIELD:
665             case ACPI_TYPE_LOCAL_INDEX_FIELD:
666             case ACPI_TYPE_DDB_HANDLE:
667 
668                 /* Valid operand */
669                 break;
670 
671             default:
672 
673                 if (AcpiGbl_EnableInterpreterSlack)
674                 {
675                     /*
676                      * Enable original behavior of Store(), allowing any and all
677                      * objects as the source operand.  The ACPI spec does not
678                      * allow this, however.
679                      */
680                     break;
681                 }
682 
683                 if (TargetOp == AML_DEBUG_OP)
684                 {
685                     /* Allow store of any object to the Debug object */
686 
687                     break;
688                 }
689 
690                 ACPI_ERROR ((AE_INFO,
691                     "Needed Integer/Buffer/String/Package/Ref/Ddb], found [%s] %p",
692                     AcpiUtGetObjectTypeName (ObjDesc), ObjDesc));
693 
694                 return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
695             }
696             goto NextOperand;
697 
698 
699         default:
700 
701             /* Unknown type */
702 
703             ACPI_ERROR ((AE_INFO,
704                 "Internal - Unknown ARGI (required operand) type 0x%X",
705                 ThisArgType));
706 
707             return_ACPI_STATUS (AE_BAD_PARAMETER);
708         }
709 
710         /*
711          * Make sure that the original object was resolved to the
712          * required object type (Simple cases only).
713          */
714         Status = AcpiExCheckObjectType (TypeNeeded,
715                         (*StackPtr)->Common.Type, *StackPtr);
716         if (ACPI_FAILURE (Status))
717         {
718             return_ACPI_STATUS (Status);
719         }
720 
721 NextOperand:
722         /*
723          * If more operands needed, decrement StackPtr to point
724          * to next operand on stack
725          */
726         if (GET_CURRENT_ARG_TYPE (ArgTypes))
727         {
728             StackPtr--;
729         }
730     }
731 
732     ACPI_DUMP_OPERANDS (WalkState->Operands,
733         AcpiPsGetOpcodeName (Opcode), WalkState->NumOperands);
734 
735     return_ACPI_STATUS (Status);
736 }
737 
738 
739