Merge branch 'master' of /pub/scm/linux/kernel/git/torvalds/linux-2.6
[linux-2.6] / drivers / acpi / dispatcher / dswexec.c
1 /******************************************************************************
2  *
3  * Module Name: dswexec - Dispatcher method execution callbacks;
4  *                        dispatch to interpreter.
5  *
6  *****************************************************************************/
7
8 /*
9  * Copyright (C) 2000 - 2008, 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 #include <acpi/acpi.h>
46 #include <acpi/acparser.h>
47 #include <acpi/amlcode.h>
48 #include <acpi/acdispat.h>
49 #include <acpi/acinterp.h>
50 #include <acpi/acnamesp.h>
51 #include <acpi/acdebug.h>
52
53 #define _COMPONENT          ACPI_DISPATCHER
54 ACPI_MODULE_NAME("dswexec")
55
56 /*
57  * Dispatch table for opcode classes
58  */
59 static ACPI_EXECUTE_OP acpi_gbl_op_type_dispatch[] = {
60         acpi_ex_opcode_0A_0T_1R,
61         acpi_ex_opcode_1A_0T_0R,
62         acpi_ex_opcode_1A_0T_1R,
63         acpi_ex_opcode_1A_1T_0R,
64         acpi_ex_opcode_1A_1T_1R,
65         acpi_ex_opcode_2A_0T_0R,
66         acpi_ex_opcode_2A_0T_1R,
67         acpi_ex_opcode_2A_1T_1R,
68         acpi_ex_opcode_2A_2T_1R,
69         acpi_ex_opcode_3A_0T_0R,
70         acpi_ex_opcode_3A_1T_1R,
71         acpi_ex_opcode_6A_0T_1R
72 };
73
74 /*****************************************************************************
75  *
76  * FUNCTION:    acpi_ds_get_predicate_value
77  *
78  * PARAMETERS:  walk_state      - Current state of the parse tree walk
79  *              result_obj      - if non-zero, pop result from result stack
80  *
81  * RETURN:      Status
82  *
83  * DESCRIPTION: Get the result of a predicate evaluation
84  *
85  ****************************************************************************/
86
87 acpi_status
88 acpi_ds_get_predicate_value(struct acpi_walk_state *walk_state,
89                             union acpi_operand_object *result_obj)
90 {
91         acpi_status status = AE_OK;
92         union acpi_operand_object *obj_desc;
93         union acpi_operand_object *local_obj_desc = NULL;
94
95         ACPI_FUNCTION_TRACE_PTR(ds_get_predicate_value, walk_state);
96
97         walk_state->control_state->common.state = 0;
98
99         if (result_obj) {
100                 status = acpi_ds_result_pop(&obj_desc, walk_state);
101                 if (ACPI_FAILURE(status)) {
102                         ACPI_EXCEPTION((AE_INFO, status,
103                                         "Could not get result from predicate evaluation"));
104
105                         return_ACPI_STATUS(status);
106                 }
107         } else {
108                 status = acpi_ds_create_operand(walk_state, walk_state->op, 0);
109                 if (ACPI_FAILURE(status)) {
110                         return_ACPI_STATUS(status);
111                 }
112
113                 status =
114                     acpi_ex_resolve_to_value(&walk_state->operands[0],
115                                              walk_state);
116                 if (ACPI_FAILURE(status)) {
117                         return_ACPI_STATUS(status);
118                 }
119
120                 obj_desc = walk_state->operands[0];
121         }
122
123         if (!obj_desc) {
124                 ACPI_ERROR((AE_INFO,
125                             "No predicate ObjDesc=%p State=%p",
126                             obj_desc, walk_state));
127
128                 return_ACPI_STATUS(AE_AML_NO_OPERAND);
129         }
130
131         /*
132          * Result of predicate evaluation must be an Integer
133          * object. Implicitly convert the argument if necessary.
134          */
135         status = acpi_ex_convert_to_integer(obj_desc, &local_obj_desc, 16);
136         if (ACPI_FAILURE(status)) {
137                 goto cleanup;
138         }
139
140         if (ACPI_GET_OBJECT_TYPE(local_obj_desc) != ACPI_TYPE_INTEGER) {
141                 ACPI_ERROR((AE_INFO,
142                             "Bad predicate (not an integer) ObjDesc=%p State=%p Type=%X",
143                             obj_desc, walk_state,
144                             ACPI_GET_OBJECT_TYPE(obj_desc)));
145
146                 status = AE_AML_OPERAND_TYPE;
147                 goto cleanup;
148         }
149
150         /* Truncate the predicate to 32-bits if necessary */
151
152         acpi_ex_truncate_for32bit_table(local_obj_desc);
153
154         /*
155          * Save the result of the predicate evaluation on
156          * the control stack
157          */
158         if (local_obj_desc->integer.value) {
159                 walk_state->control_state->common.value = TRUE;
160         } else {
161                 /*
162                  * Predicate is FALSE, we will just toss the
163                  * rest of the package
164                  */
165                 walk_state->control_state->common.value = FALSE;
166                 status = AE_CTRL_FALSE;
167         }
168
169       cleanup:
170
171         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Completed a predicate eval=%X Op=%p\n",
172                           walk_state->control_state->common.value,
173                           walk_state->op));
174
175         /* Break to debugger to display result */
176
177         ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
178                            (local_obj_desc, walk_state));
179
180         /*
181          * Delete the predicate result object (we know that
182          * we don't need it anymore)
183          */
184         if (local_obj_desc != obj_desc) {
185                 acpi_ut_remove_reference(local_obj_desc);
186         }
187         acpi_ut_remove_reference(obj_desc);
188
189         walk_state->control_state->common.state = ACPI_CONTROL_NORMAL;
190         return_ACPI_STATUS(status);
191 }
192
193 /*****************************************************************************
194  *
195  * FUNCTION:    acpi_ds_exec_begin_op
196  *
197  * PARAMETERS:  walk_state      - Current state of the parse tree walk
198  *              out_op          - Where to return op if a new one is created
199  *
200  * RETURN:      Status
201  *
202  * DESCRIPTION: Descending callback used during the execution of control
203  *              methods.  This is where most operators and operands are
204  *              dispatched to the interpreter.
205  *
206  ****************************************************************************/
207
208 acpi_status
209 acpi_ds_exec_begin_op(struct acpi_walk_state *walk_state,
210                       union acpi_parse_object **out_op)
211 {
212         union acpi_parse_object *op;
213         acpi_status status = AE_OK;
214         u32 opcode_class;
215
216         ACPI_FUNCTION_TRACE_PTR(ds_exec_begin_op, walk_state);
217
218         op = walk_state->op;
219         if (!op) {
220                 status = acpi_ds_load2_begin_op(walk_state, out_op);
221                 if (ACPI_FAILURE(status)) {
222                         goto error_exit;
223                 }
224
225                 op = *out_op;
226                 walk_state->op = op;
227                 walk_state->opcode = op->common.aml_opcode;
228                 walk_state->op_info =
229                     acpi_ps_get_opcode_info(op->common.aml_opcode);
230
231                 if (acpi_ns_opens_scope(walk_state->op_info->object_type)) {
232                         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
233                                           "(%s) Popping scope for Op %p\n",
234                                           acpi_ut_get_type_name(walk_state->
235                                                                 op_info->
236                                                                 object_type),
237                                           op));
238
239                         status = acpi_ds_scope_stack_pop(walk_state);
240                         if (ACPI_FAILURE(status)) {
241                                 goto error_exit;
242                         }
243                 }
244         }
245
246         if (op == walk_state->origin) {
247                 if (out_op) {
248                         *out_op = op;
249                 }
250
251                 return_ACPI_STATUS(AE_OK);
252         }
253
254         /*
255          * If the previous opcode was a conditional, this opcode
256          * must be the beginning of the associated predicate.
257          * Save this knowledge in the current scope descriptor
258          */
259         if ((walk_state->control_state) &&
260             (walk_state->control_state->common.state ==
261              ACPI_CONTROL_CONDITIONAL_EXECUTING)) {
262                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
263                                   "Exec predicate Op=%p State=%p\n", op,
264                                   walk_state));
265
266                 walk_state->control_state->common.state =
267                     ACPI_CONTROL_PREDICATE_EXECUTING;
268
269                 /* Save start of predicate */
270
271                 walk_state->control_state->control.predicate_op = op;
272         }
273
274         opcode_class = walk_state->op_info->class;
275
276         /* We want to send namepaths to the load code */
277
278         if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
279                 opcode_class = AML_CLASS_NAMED_OBJECT;
280         }
281
282         /*
283          * Handle the opcode based upon the opcode type
284          */
285         switch (opcode_class) {
286         case AML_CLASS_CONTROL:
287
288                 status = acpi_ds_exec_begin_control_op(walk_state, op);
289                 break;
290
291         case AML_CLASS_NAMED_OBJECT:
292
293                 if (walk_state->walk_type & ACPI_WALK_METHOD) {
294                         /*
295                          * Found a named object declaration during method execution;
296                          * we must enter this object into the namespace.  The created
297                          * object is temporary and will be deleted upon completion of
298                          * the execution of this method.
299                          */
300                         status = acpi_ds_load2_begin_op(walk_state, NULL);
301                 }
302
303                 break;
304
305         case AML_CLASS_EXECUTE:
306         case AML_CLASS_CREATE:
307
308                 break;
309
310         default:
311                 break;
312         }
313
314         /* Nothing to do here during method execution */
315
316         return_ACPI_STATUS(status);
317
318       error_exit:
319         status = acpi_ds_method_error(status, walk_state);
320         return_ACPI_STATUS(status);
321 }
322
323 /*****************************************************************************
324  *
325  * FUNCTION:    acpi_ds_exec_end_op
326  *
327  * PARAMETERS:  walk_state      - Current state of the parse tree walk
328  *
329  * RETURN:      Status
330  *
331  * DESCRIPTION: Ascending callback used during the execution of control
332  *              methods.  The only thing we really need to do here is to
333  *              notice the beginning of IF, ELSE, and WHILE blocks.
334  *
335  ****************************************************************************/
336
337 acpi_status acpi_ds_exec_end_op(struct acpi_walk_state *walk_state)
338 {
339         union acpi_parse_object *op;
340         acpi_status status = AE_OK;
341         u32 op_type;
342         u32 op_class;
343         union acpi_parse_object *next_op;
344         union acpi_parse_object *first_arg;
345
346         ACPI_FUNCTION_TRACE_PTR(ds_exec_end_op, walk_state);
347
348         op = walk_state->op;
349         op_type = walk_state->op_info->type;
350         op_class = walk_state->op_info->class;
351
352         if (op_class == AML_CLASS_UNKNOWN) {
353                 ACPI_ERROR((AE_INFO, "Unknown opcode %X",
354                             op->common.aml_opcode));
355                 return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
356         }
357
358         first_arg = op->common.value.arg;
359
360         /* Init the walk state */
361
362         walk_state->num_operands = 0;
363         walk_state->operand_index = 0;
364         walk_state->return_desc = NULL;
365         walk_state->result_obj = NULL;
366
367         /* Call debugger for single step support (DEBUG build only) */
368
369         ACPI_DEBUGGER_EXEC(status =
370                            acpi_db_single_step(walk_state, op, op_class));
371         ACPI_DEBUGGER_EXEC(if (ACPI_FAILURE(status)) {
372                            return_ACPI_STATUS(status);}
373         ) ;
374
375         /* Decode the Opcode Class */
376
377         switch (op_class) {
378         case AML_CLASS_ARGUMENT:        /* Constants, literals, etc. */
379
380                 if (walk_state->opcode == AML_INT_NAMEPATH_OP) {
381                         status = acpi_ds_evaluate_name_path(walk_state);
382                         if (ACPI_FAILURE(status)) {
383                                 goto cleanup;
384                         }
385                 }
386                 break;
387
388         case AML_CLASS_EXECUTE: /* Most operators with arguments */
389
390                 /* Build resolved operand stack */
391
392                 status = acpi_ds_create_operands(walk_state, first_arg);
393                 if (ACPI_FAILURE(status)) {
394                         goto cleanup;
395                 }
396
397                 /*
398                  * All opcodes require operand resolution, with the only exceptions
399                  * being the object_type and size_of operators.
400                  */
401                 if (!(walk_state->op_info->flags & AML_NO_OPERAND_RESOLVE)) {
402
403                         /* Resolve all operands */
404
405                         status = acpi_ex_resolve_operands(walk_state->opcode,
406                                                           &(walk_state->
407                                                             operands
408                                                             [walk_state->
409                                                              num_operands - 1]),
410                                                           walk_state);
411                         if (ACPI_SUCCESS(status)) {
412                                 ACPI_DUMP_OPERANDS(ACPI_WALK_OPERANDS,
413                                                    ACPI_IMODE_EXECUTE,
414                                                    acpi_ps_get_opcode_name
415                                                    (walk_state->opcode),
416                                                    walk_state->num_operands,
417                                                    "after ExResolveOperands");
418                         }
419                 }
420
421                 if (ACPI_SUCCESS(status)) {
422                         /*
423                          * Dispatch the request to the appropriate interpreter handler
424                          * routine.  There is one routine per opcode "type" based upon the
425                          * number of opcode arguments and return type.
426                          */
427                         status =
428                             acpi_gbl_op_type_dispatch[op_type] (walk_state);
429                 } else {
430                         /*
431                          * Treat constructs of the form "Store(LocalX,LocalX)" as noops when the
432                          * Local is uninitialized.
433                          */
434                         if ((status == AE_AML_UNINITIALIZED_LOCAL) &&
435                             (walk_state->opcode == AML_STORE_OP) &&
436                             (walk_state->operands[0]->common.type ==
437                              ACPI_TYPE_LOCAL_REFERENCE)
438                             && (walk_state->operands[1]->common.type ==
439                                 ACPI_TYPE_LOCAL_REFERENCE)
440                             && (walk_state->operands[0]->reference.opcode ==
441                                 walk_state->operands[1]->reference.opcode)
442                             && (walk_state->operands[0]->reference.offset ==
443                                 walk_state->operands[1]->reference.offset)) {
444                                 status = AE_OK;
445                         } else {
446                                 ACPI_EXCEPTION((AE_INFO, status,
447                                                 "While resolving operands for [%s]",
448                                                 acpi_ps_get_opcode_name
449                                                 (walk_state->opcode)));
450                         }
451                 }
452
453                 /* Always delete the argument objects and clear the operand stack */
454
455                 acpi_ds_clear_operands(walk_state);
456
457                 /*
458                  * If a result object was returned from above, push it on the
459                  * current result stack
460                  */
461                 if (ACPI_SUCCESS(status) && walk_state->result_obj) {
462                         status =
463                             acpi_ds_result_push(walk_state->result_obj,
464                                                 walk_state);
465                 }
466                 break;
467
468         default:
469
470                 switch (op_type) {
471                 case AML_TYPE_CONTROL:  /* Type 1 opcode, IF/ELSE/WHILE/NOOP */
472
473                         /* 1 Operand, 0 external_result, 0 internal_result */
474
475                         status = acpi_ds_exec_end_control_op(walk_state, op);
476
477                         break;
478
479                 case AML_TYPE_METHOD_CALL:
480
481                         /*
482                          * If the method is referenced from within a package
483                          * declaration, it is not a invocation of the method, just
484                          * a reference to it.
485                          */
486                         if ((op->asl.parent) &&
487                             ((op->asl.parent->asl.aml_opcode == AML_PACKAGE_OP)
488                              || (op->asl.parent->asl.aml_opcode ==
489                                  AML_VAR_PACKAGE_OP))) {
490                                 ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
491                                                   "Method Reference in a Package, Op=%p\n",
492                                                   op));
493
494                                 op->common.node =
495                                     (struct acpi_namespace_node *)op->asl.value.
496                                     arg->asl.node;
497                                 acpi_ut_add_reference(op->asl.value.arg->asl.
498                                                       node->object);
499                                 return_ACPI_STATUS(AE_OK);
500                         }
501
502                         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
503                                           "Method invocation, Op=%p\n", op));
504
505                         /*
506                          * (AML_METHODCALL) Op->Asl.Value.Arg->Asl.Node contains
507                          * the method Node pointer
508                          */
509                         /* next_op points to the op that holds the method name */
510
511                         next_op = first_arg;
512
513                         /* next_op points to first argument op */
514
515                         next_op = next_op->common.next;
516
517                         /*
518                          * Get the method's arguments and put them on the operand stack
519                          */
520                         status = acpi_ds_create_operands(walk_state, next_op);
521                         if (ACPI_FAILURE(status)) {
522                                 break;
523                         }
524
525                         /*
526                          * Since the operands will be passed to another control method,
527                          * we must resolve all local references here (Local variables,
528                          * arguments to *this* method, etc.)
529                          */
530                         status = acpi_ds_resolve_operands(walk_state);
531                         if (ACPI_FAILURE(status)) {
532
533                                 /* On error, clear all resolved operands */
534
535                                 acpi_ds_clear_operands(walk_state);
536                                 break;
537                         }
538
539                         /*
540                          * Tell the walk loop to preempt this running method and
541                          * execute the new method
542                          */
543                         status = AE_CTRL_TRANSFER;
544
545                         /*
546                          * Return now; we don't want to disturb anything,
547                          * especially the operand count!
548                          */
549                         return_ACPI_STATUS(status);
550
551                 case AML_TYPE_CREATE_FIELD:
552
553                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
554                                           "Executing CreateField Buffer/Index Op=%p\n",
555                                           op));
556
557                         status = acpi_ds_load2_end_op(walk_state);
558                         if (ACPI_FAILURE(status)) {
559                                 break;
560                         }
561
562                         status =
563                             acpi_ds_eval_buffer_field_operands(walk_state, op);
564                         break;
565
566                 case AML_TYPE_CREATE_OBJECT:
567
568                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
569                                           "Executing CreateObject (Buffer/Package) Op=%p\n",
570                                           op));
571
572                         switch (op->common.parent->common.aml_opcode) {
573                         case AML_NAME_OP:
574
575                                 /*
576                                  * Put the Node on the object stack (Contains the ACPI Name
577                                  * of this object)
578                                  */
579                                 walk_state->operands[0] =
580                                     (void *)op->common.parent->common.node;
581                                 walk_state->num_operands = 1;
582
583                                 status = acpi_ds_create_node(walk_state,
584                                                              op->common.parent->
585                                                              common.node,
586                                                              op->common.parent);
587                                 if (ACPI_FAILURE(status)) {
588                                         break;
589                                 }
590
591                                 /* Fall through */
592                                 /*lint -fallthrough */
593
594                         case AML_INT_EVAL_SUBTREE_OP:
595
596                                 status =
597                                     acpi_ds_eval_data_object_operands
598                                     (walk_state, op,
599                                      acpi_ns_get_attached_object(op->common.
600                                                                  parent->common.
601                                                                  node));
602                                 break;
603
604                         default:
605
606                                 status =
607                                     acpi_ds_eval_data_object_operands
608                                     (walk_state, op, NULL);
609                                 break;
610                         }
611
612                         /*
613                          * If a result object was returned from above, push it on the
614                          * current result stack
615                          */
616                         if (walk_state->result_obj) {
617                                 status =
618                                     acpi_ds_result_push(walk_state->result_obj,
619                                                         walk_state);
620                         }
621                         break;
622
623                 case AML_TYPE_NAMED_FIELD:
624                 case AML_TYPE_NAMED_COMPLEX:
625                 case AML_TYPE_NAMED_SIMPLE:
626                 case AML_TYPE_NAMED_NO_OBJ:
627
628                         status = acpi_ds_load2_end_op(walk_state);
629                         if (ACPI_FAILURE(status)) {
630                                 break;
631                         }
632
633                         if (op->common.aml_opcode == AML_REGION_OP) {
634                                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
635                                                   "Executing OpRegion Address/Length Op=%p\n",
636                                                   op));
637
638                                 status =
639                                     acpi_ds_eval_region_operands(walk_state,
640                                                                  op);
641                                 if (ACPI_FAILURE(status)) {
642                                         break;
643                                 }
644                         } else if (op->common.aml_opcode == AML_DATA_REGION_OP) {
645                                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
646                                                   "Executing DataTableRegion Strings Op=%p\n",
647                                                   op));
648
649                                 status =
650                                     acpi_ds_eval_table_region_operands
651                                     (walk_state, op);
652                                 if (ACPI_FAILURE(status)) {
653                                         break;
654                                 }
655                         } else if (op->common.aml_opcode == AML_BANK_FIELD_OP) {
656                                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
657                                                   "Executing BankField Op=%p\n",
658                                                   op));
659
660                                 status =
661                                     acpi_ds_eval_bank_field_operands(walk_state,
662                                                                      op);
663                                 if (ACPI_FAILURE(status)) {
664                                         break;
665                                 }
666                         }
667                         break;
668
669                 case AML_TYPE_UNDEFINED:
670
671                         ACPI_ERROR((AE_INFO,
672                                     "Undefined opcode type Op=%p", op));
673                         return_ACPI_STATUS(AE_NOT_IMPLEMENTED);
674
675                 case AML_TYPE_BOGUS:
676
677                         ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
678                                           "Internal opcode=%X type Op=%p\n",
679                                           walk_state->opcode, op));
680                         break;
681
682                 default:
683
684                         ACPI_ERROR((AE_INFO,
685                                     "Unimplemented opcode, class=%X type=%X Opcode=%X Op=%p",
686                                     op_class, op_type, op->common.aml_opcode,
687                                     op));
688
689                         status = AE_NOT_IMPLEMENTED;
690                         break;
691                 }
692         }
693
694         /*
695          * ACPI 2.0 support for 64-bit integers: Truncate numeric
696          * result value if we are executing from a 32-bit ACPI table
697          */
698         acpi_ex_truncate_for32bit_table(walk_state->result_obj);
699
700         /*
701          * Check if we just completed the evaluation of a
702          * conditional predicate
703          */
704         if ((ACPI_SUCCESS(status)) &&
705             (walk_state->control_state) &&
706             (walk_state->control_state->common.state ==
707              ACPI_CONTROL_PREDICATE_EXECUTING) &&
708             (walk_state->control_state->control.predicate_op == op)) {
709                 status =
710                     acpi_ds_get_predicate_value(walk_state,
711                                                 walk_state->result_obj);
712                 walk_state->result_obj = NULL;
713         }
714
715       cleanup:
716
717         if (walk_state->result_obj) {
718
719                 /* Break to debugger to display result */
720
721                 ACPI_DEBUGGER_EXEC(acpi_db_display_result_object
722                                    (walk_state->result_obj, walk_state));
723
724                 /*
725                  * Delete the result op if and only if:
726                  * Parent will not use the result -- such as any
727                  * non-nested type2 op in a method (parent will be method)
728                  */
729                 acpi_ds_delete_result_if_not_used(op, walk_state->result_obj,
730                                                   walk_state);
731         }
732 #ifdef _UNDER_DEVELOPMENT
733
734         if (walk_state->parser_state.aml == walk_state->parser_state.aml_end) {
735                 acpi_db_method_end(walk_state);
736         }
737 #endif
738
739         /* Invoke exception handler on error */
740
741         if (ACPI_FAILURE(status)) {
742                 status = acpi_ds_method_error(status, walk_state);
743         }
744
745         /* Always clear the object stack */
746
747         walk_state->num_operands = 0;
748         return_ACPI_STATUS(status);
749 }