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 - 2004, R. Byron Moore
  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
  46 #include <acpi/acpi.h>
  47 #include <acpi/acparser.h>
  48 #include <acpi/amlcode.h>
  49 #include <acpi/acdispat.h>
  50 #include <acpi/acinterp.h>
  51 #include <acpi/acnamesp.h>
  52 #include <acpi/acdebug.h>
  53 #include <acpi/acdisasm.h>
  54
  55
  56 #define _COMPONENT          ACPI_DISPATCHER
  57          ACPI_MODULE_NAME    ("dswexec")
  58
  59 /*
  60  * Dispatch table for opcode classes
  61  */
  62 static ACPI_EXECUTE_OP      acpi_gbl_op_type_dispatch [] = {
  63                           acpi_ex_opcode_0A_0T_1R,
  64                           acpi_ex_opcode_1A_0T_0R,
  65                           acpi_ex_opcode_1A_0T_1R,
  66                           acpi_ex_opcode_1A_1T_0R,
  67                           acpi_ex_opcode_1A_1T_1R,
  68                           acpi_ex_opcode_2A_0T_0R,
  69                           acpi_ex_opcode_2A_0T_1R,
  70                           acpi_ex_opcode_2A_1T_1R,
  71                           acpi_ex_opcode_2A_2T_1R,
  72                           acpi_ex_opcode_3A_0T_0R,
  73                           acpi_ex_opcode_3A_1T_1R,
  74                           acpi_ex_opcode_6A_0T_1R};
  75
  76 /*****************************************************************************
  77  *
  78  * FUNCTION:    acpi_ds_get_predicate_value
  79  *
  80  * PARAMETERS:  walk_state      - Current state of the parse tree walk
  81  *
  82  * RETURN:      Status
  83  *
  84  * DESCRIPTION: Get the result of a predicate evaluation
  85  *
  86  ****************************************************************************/
  87
  88 acpi_status
  89 acpi_ds_get_predicate_value (
  90         struct acpi_walk_state          *walk_state,
  91         union acpi_operand_object       *result_obj) {
  92         acpi_status                     status = AE_OK;
  93         union acpi_operand_object       *obj_desc;
  94
  95
  96         ACPI_FUNCTION_TRACE_PTR ("ds_get_predicate_value", walk_state);
  97
  98
  99         walk_state->control_state->common.state = 0;
 100
 101         if (result_obj) {
 102                 status = acpi_ds_result_pop (&obj_desc, walk_state);
 103                 if (ACPI_FAILURE (status)) {
 104                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 105                                 "Could not get result from predicate evaluation, %s\n",
 106                                 acpi_format_exception (status)));
 107
 108                         return_ACPI_STATUS (status);
 109                 }
 110         }
 111         else {
 112                 status = acpi_ds_create_operand (walk_state, walk_state->op, 0);
 113                 if (ACPI_FAILURE (status)) {
 114                         return_ACPI_STATUS (status);
 115                 }
 116
 117                 status = acpi_ex_resolve_to_value (&walk_state->operands [0], walk_state);
 118                 if (ACPI_FAILURE (status)) {
 119                         return_ACPI_STATUS (status);
 120                 }
 121
 122                 obj_desc = walk_state->operands [0];
 123         }
 124
 125         if (!obj_desc) {
 126                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "No predicate obj_desc=%p State=%p\n",
 127                         obj_desc, walk_state));
 128
 129                 return_ACPI_STATUS (AE_AML_NO_OPERAND);
 130         }
 131
 132         /*
 133          * Result of predicate evaluation currently must
 134          * be a number
 135          */
 136         if (ACPI_GET_OBJECT_TYPE (obj_desc) != ACPI_TYPE_INTEGER) {
 137                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 138                         "Bad predicate (not a number) obj_desc=%p State=%p Type=%X\n",
 139                         obj_desc, walk_state, ACPI_GET_OBJECT_TYPE (obj_desc)));
 140
 141                 status = AE_AML_OPERAND_TYPE;
 142                 goto cleanup;
 143         }
 144
 145         /* Truncate the predicate to 32-bits if necessary */
 146
 147         acpi_ex_truncate_for32bit_table (obj_desc);
 148
 149         /*
 150          * Save the result of the predicate evaluation on
 151          * the control stack
 152          */
 153         if (obj_desc->integer.value) {
 154                 walk_state->control_state->common.value = TRUE;
 155         }
 156         else {
 157                 /*
 158                  * Predicate is FALSE, we will just toss the
 159                  * rest of the package
 160                  */
 161                 walk_state->control_state->common.value = FALSE;
 162                 status = AE_CTRL_FALSE;
 163         }
 164
 165
 166 cleanup:
 167
 168         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Completed a predicate eval=%X Op=%p\n",
 169                 walk_state->control_state->common.value, walk_state->op));
 170
 171          /* Break to debugger to display result */
 172
 173         ACPI_DEBUGGER_EXEC (acpi_db_display_result_object (obj_desc, walk_state));
 174
 175         /*
 176          * Delete the predicate result object (we know that
 177          * we don't need it anymore)
 178          */
 179         acpi_ut_remove_reference (obj_desc);
 180
 181         walk_state->control_state->common.state = ACPI_CONTROL_NORMAL;
 182         return_ACPI_STATUS (status);
 183 }
 184
 185
 186 /*****************************************************************************
 187  *
 188  * FUNCTION:    acpi_ds_exec_begin_op
 189  *
 190  * PARAMETERS:  walk_state      - Current state of the parse tree walk
 191  *              out_op          - Return op if a new one is created
 192  *
 193  * RETURN:      Status
 194  *
 195  * DESCRIPTION: Descending callback used during the execution of control
 196  *              methods.  This is where most operators and operands are
 197  *              dispatched to the interpreter.
 198  *
 199  ****************************************************************************/
 200
 201 acpi_status
 202 acpi_ds_exec_begin_op (
 203         struct acpi_walk_state          *walk_state,
 204         union acpi_parse_object         **out_op)
 205 {
 206         union acpi_parse_object         *op;
 207         acpi_status                     status = AE_OK;
 208         u32                             opcode_class;
 209
 210
 211         ACPI_FUNCTION_TRACE_PTR ("ds_exec_begin_op", walk_state);
 212
 213
 214         op = walk_state->op;
 215         if (!op) {
 216                 status = acpi_ds_load2_begin_op (walk_state, out_op);
 217                 if (ACPI_FAILURE (status)) {
 218                         return_ACPI_STATUS (status);
 219                 }
 220
 221                 op = *out_op;
 222                 walk_state->op = op;
 223                 walk_state->opcode = op->common.aml_opcode;
 224                 walk_state->op_info = acpi_ps_get_opcode_info (op->common.aml_opcode);
 225
 226                 if (acpi_ns_opens_scope (walk_state->op_info->object_type)) {
 227                         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "(%s) Popping scope for Op %p\n",
 228                                 acpi_ut_get_type_name (walk_state->op_info->object_type), op));
 229
 230                         status = acpi_ds_scope_stack_pop (walk_state);
 231                         if (ACPI_FAILURE (status)) {
 232                                 return_ACPI_STATUS (status);
 233                         }
 234                 }
 235         }
 236
 237         if (op == walk_state->origin) {
 238                 if (out_op) {
 239                         *out_op = op;
 240                 }
 241
 242                 return_ACPI_STATUS (AE_OK);
 243         }
 244
 245         /*
 246          * If the previous opcode was a conditional, this opcode
 247          * must be the beginning of the associated predicate.
 248          * Save this knowledge in the current scope descriptor
 249          */
 250         if ((walk_state->control_state) &&
 251                 (walk_state->control_state->common.state ==
 252                         ACPI_CONTROL_CONDITIONAL_EXECUTING)) {
 253                 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "Exec predicate Op=%p State=%p\n",
 254                                   op, walk_state));
 255
 256                 walk_state->control_state->common.state = ACPI_CONTROL_PREDICATE_EXECUTING;
 257
 258                 /* Save start of predicate */
 259
 260                 walk_state->control_state->control.predicate_op = op;
 261         }
 262
 263
 264         opcode_class = walk_state->op_info->class;
 265
 266         /* We want to send namepaths to the load code */
 267
 268         if (op->common.aml_opcode == AML_INT_NAMEPATH_OP) {
 269                 opcode_class = AML_CLASS_NAMED_OBJECT;
 270         }
 271
 272         /*
 273          * Handle the opcode based upon the opcode type
 274          */
 275         switch (opcode_class) {
 276         case AML_CLASS_CONTROL:
 277
 278                 status = acpi_ds_result_stack_push (walk_state);
 279                 if (ACPI_FAILURE (status)) {
 280                         return_ACPI_STATUS (status);
 281                 }
 282
 283                 status = acpi_ds_exec_begin_control_op (walk_state, op);
 284                 break;
 285
 286
 287         case AML_CLASS_NAMED_OBJECT:
 288
 289                 if (walk_state->walk_type == ACPI_WALK_METHOD) {
 290                         /*
 291                          * Found a named object declaration during method
 292                          * execution;  we must enter this object into the
 293                          * namespace.  The created object is temporary and
 294                          * will be deleted upon completion of the execution
 295                          * of this method.
 296                          */
 297                         status = acpi_ds_load2_begin_op (walk_state, NULL);
 298                 }
 299
 300                 if (op->common.aml_opcode == AML_REGION_OP) {
 301                         status = acpi_ds_result_stack_push (walk_state);
 302                 }
 303                 break;
 304
 305
 306         case AML_CLASS_EXECUTE:
 307         case AML_CLASS_CREATE:
 308
 309                 /* most operators with arguments */
 310                 /* Start a new result/operand state */
 311
 312                 status = acpi_ds_result_stack_push (walk_state);
 313                 break;
 314
 315
 316         default:
 317                 break;
 318         }
 319
 320         /* Nothing to do here during method execution */
 321
 322         return_ACPI_STATUS (status);
 323 }
 324
 325
 326 /*****************************************************************************
 327  *
 328  * FUNCTION:    acpi_ds_exec_end_op
 329  *
 330  * PARAMETERS:  walk_state      - Current state of the parse tree walk
 331  *              Op              - Op that has been just been completed in the
 332  *                                walk;  Arguments have now been evaluated.
 333  *
 334  * RETURN:      Status
 335  *
 336  * DESCRIPTION: Ascending callback used during the execution of control
 337  *              methods.  The only thing we really need to do here is to
 338  *              notice the beginning of IF, ELSE, and WHILE blocks.
 339  *
 340  ****************************************************************************/
 341
 342 acpi_status
 343 acpi_ds_exec_end_op (
 344         struct acpi_walk_state          *walk_state)
 345 {
 346         union acpi_parse_object         *op;
 347         acpi_status                     status = AE_OK;
 348         u32                             op_type;
 349         u32                             op_class;
 350         union acpi_parse_object         *next_op;
 351         union acpi_parse_object         *first_arg;
 352
 353
 354         ACPI_FUNCTION_TRACE_PTR ("ds_exec_end_op", walk_state);
 355
 356
 357         op      = walk_state->op;
 358         op_type = walk_state->op_info->type;
 359         op_class = walk_state->op_info->class;
 360
 361         if (op_class == AML_CLASS_UNKNOWN) {
 362                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Unknown opcode %X\n", op->common.aml_opcode));
 363                 return_ACPI_STATUS (AE_NOT_IMPLEMENTED);
 364         }
 365
 366         first_arg = op->common.value.arg;
 367
 368         /* Init the walk state */
 369
 370         walk_state->num_operands = 0;
 371         walk_state->return_desc = NULL;
 372         walk_state->result_obj = NULL;
 373
 374         /* Call debugger for single step support (DEBUG build only) */
 375
 376         ACPI_DEBUGGER_EXEC (status = acpi_db_single_step (walk_state, op, op_class));
 377         ACPI_DEBUGGER_EXEC (if (ACPI_FAILURE (status)) {return_ACPI_STATUS (status);});
 378
 379         /* Decode the Opcode Class */
 380
 381         switch (op_class) {
 382         case AML_CLASS_ARGUMENT:    /* constants, literals, etc. -- do nothing */
 383                 break;
 384
 385
 386         case AML_CLASS_EXECUTE:     /* most operators with arguments */
 387
 388                 /* Build resolved operand stack */
 389
 390                 status = acpi_ds_create_operands (walk_state, first_arg);
 391                 if (ACPI_FAILURE (status)) {
 392                         goto cleanup;
 393                 }
 394
 395                 /* Done with this result state (Now that operand stack is built) */
 396
 397                 status = acpi_ds_result_stack_pop (walk_state);
 398                 if (ACPI_FAILURE (status)) {
 399                         goto cleanup;
 400                 }
 401
 402                 /* Resolve all operands */
 403
 404                 status = acpi_ex_resolve_operands (walk_state->opcode,
 405                                   &(walk_state->operands [walk_state->num_operands -1]),
 406                                   walk_state);
 407                 if (ACPI_SUCCESS (status)) {
 408                         ACPI_DUMP_OPERANDS (ACPI_WALK_OPERANDS, ACPI_IMODE_EXECUTE,
 409                                           acpi_ps_get_opcode_name (walk_state->opcode),
 410                                           walk_state->num_operands, "after ex_resolve_operands");
 411
 412                         /*
 413                          * Dispatch the request to the appropriate interpreter handler
 414                          * routine.  There is one routine per opcode "type" based upon the
 415                          * number of opcode arguments and return type.
 416                          */
 417                         status = acpi_gbl_op_type_dispatch[op_type] (walk_state);
 418                 }
 419                 else {
 420                         /*
 421                          * Treat constructs of the form "Store(local_x,local_x)" as noops when the
 422                          * Local is uninitialized.
 423                          */
 424                         if  ((status == AE_AML_UNINITIALIZED_LOCAL) &&
 425                                 (walk_state->opcode == AML_STORE_OP) &&
 426                                 (walk_state->operands[0]->common.type == ACPI_TYPE_LOCAL_REFERENCE) &&
 427                                 (walk_state->operands[1]->common.type == ACPI_TYPE_LOCAL_REFERENCE) &&
 428                                 (walk_state->operands[0]->reference.opcode ==
 429                                  walk_state->operands[1]->reference.opcode) &&
 430                                 (walk_state->operands[0]->reference.offset ==
 431                                  walk_state->operands[1]->reference.offset)) {
 432                                 status = AE_OK;
 433                         }
 434                         else {
 435                                 ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 436                                         "[%s]: Could not resolve operands, %s\n",
 437                                         acpi_ps_get_opcode_name (walk_state->opcode),
 438                                         acpi_format_exception (status)));
 439                         }
 440                 }
 441
 442                 /* Always delete the argument objects and clear the operand stack */
 443
 444                 acpi_ds_clear_operands (walk_state);
 445
 446                 /*
 447                  * If a result object was returned from above, push it on the
 448                  * current result stack
 449                  */
 450                 if (ACPI_SUCCESS (status) &&
 451                         walk_state->result_obj) {
 452                         status = acpi_ds_result_push (walk_state->result_obj, walk_state);
 453                 }
 454
 455                 break;
 456
 457
 458         default:
 459
 460                 switch (op_type) {
 461                 case AML_TYPE_CONTROL:    /* Type 1 opcode, IF/ELSE/WHILE/NOOP */
 462
 463                         /* 1 Operand, 0 external_result, 0 internal_result */
 464
 465                         status = acpi_ds_exec_end_control_op (walk_state, op);
 466                         if (ACPI_FAILURE (status)) {
 467                                 break;
 468                         }
 469
 470                         status = acpi_ds_result_stack_pop (walk_state);
 471                         break;
 472
 473
 474                 case AML_TYPE_METHOD_CALL:
 475
 476                         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH, "Method invocation, Op=%p\n", op));
 477
 478                         /*
 479                          * (AML_METHODCALL) Op->Value->Arg->Node contains
 480                          * the method Node pointer
 481                          */
 482                         /* next_op points to the op that holds the method name */
 483
 484                         next_op = first_arg;
 485
 486                         /* next_op points to first argument op */
 487
 488                         next_op = next_op->common.next;
 489
 490                         /*
 491                          * Get the method's arguments and put them on the operand stack
 492                          */
 493                         status = acpi_ds_create_operands (walk_state, next_op);
 494                         if (ACPI_FAILURE (status)) {
 495                                 break;
 496                         }
 497
 498                         /*
 499                          * Since the operands will be passed to another control method,
 500                          * we must resolve all local references here (Local variables,
 501                          * arguments to *this* method, etc.)
 502                          */
 503                         status = acpi_ds_resolve_operands (walk_state);
 504                         if (ACPI_FAILURE (status)) {
 505                                 /* On error, clear all resolved operands */
 506
 507                                 acpi_ds_clear_operands (walk_state);
 508                                 break;
 509                         }
 510
 511                         /*
 512                          * Tell the walk loop to preempt this running method and
 513                          * execute the new method
 514                          */
 515                         status = AE_CTRL_TRANSFER;
 516
 517                         /*
 518                          * Return now; we don't want to disturb anything,
 519                          * especially the operand count!
 520                          */
 521                         return_ACPI_STATUS (status);
 522
 523
 524                 case AML_TYPE_CREATE_FIELD:
 525
 526                         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 527                                 "Executing create_field Buffer/Index Op=%p\n", op));
 528
 529                         status = acpi_ds_load2_end_op (walk_state);
 530                         if (ACPI_FAILURE (status)) {
 531                                 break;
 532                         }
 533
 534                         status = acpi_ds_eval_buffer_field_operands (walk_state, op);
 535                         break;
 536
 537
 538                 case AML_TYPE_CREATE_OBJECT:
 539
 540                         ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 541                                 "Executing create_object (Buffer/Package) Op=%p\n", op));
 542
 543                         switch (op->common.parent->common.aml_opcode) {
 544                         case AML_NAME_OP:
 545
 546                                 /*
 547                                  * Put the Node on the object stack (Contains the ACPI Name of
 548                                  * this object)
 549                                  */
 550                                 walk_state->operands[0] = (void *) op->common.parent->common.node;
 551                                 walk_state->num_operands = 1;
 552
 553                                 status = acpi_ds_create_node (walk_state, op->common.parent->common.node, op->common.parent);
 554                                 if (ACPI_FAILURE (status)) {
 555                                         break;
 556                                 }
 557
 558                                 /* Fall through */
 559                                 /*lint -fallthrough */
 560
 561                         case AML_INT_EVAL_SUBTREE_OP:
 562
 563                                 status = acpi_ds_eval_data_object_operands (walk_state, op,
 564                                                   acpi_ns_get_attached_object (op->common.parent->common.node));
 565                                 break;
 566
 567                         default:
 568
 569                                 status = acpi_ds_eval_data_object_operands (walk_state, op, NULL);
 570                                 break;
 571                         }
 572
 573                         /*
 574                          * If a result object was returned from above, push it on the
 575                          * current result stack
 576                          */
 577                         if (ACPI_SUCCESS (status) &&
 578                                 walk_state->result_obj) {
 579                                 status = acpi_ds_result_push (walk_state->result_obj, walk_state);
 580                         }
 581                         break;
 582
 583
 584                 case AML_TYPE_NAMED_FIELD:
 585                 case AML_TYPE_NAMED_COMPLEX:
 586                 case AML_TYPE_NAMED_SIMPLE:
 587                 case AML_TYPE_NAMED_NO_OBJ:
 588
 589                         status = acpi_ds_load2_end_op (walk_state);
 590                         if (ACPI_FAILURE (status)) {
 591                                 break;
 592                         }
 593
 594                         if (op->common.aml_opcode == AML_REGION_OP) {
 595                                 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
 596                                         "Executing op_region Address/Length Op=%p\n", op));
 597
 598                                 status = acpi_ds_eval_region_operands (walk_state, op);
 599                                 if (ACPI_FAILURE (status)) {
 600                                         break;
 601                                 }
 602
 603                                 status = acpi_ds_result_stack_pop (walk_state);
 604                         }
 605
 606                         break;
 607
 608
 609                 case AML_TYPE_UNDEFINED:
 610
 611                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Undefined opcode type Op=%p\n", op));
 612                         return_ACPI_STATUS (AE_NOT_IMPLEMENTED);
 613
 614
 615                 case AML_TYPE_BOGUS:
 616
 617                         ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
 618                                 "Internal opcode=%X type Op=%p\n",
 619                                 walk_state->opcode, op));
 620                         break;
 621
 622
 623                 default:
 624
 625                         ACPI_DEBUG_PRINT ((ACPI_DB_ERROR,
 626                                 "Unimplemented opcode, class=%X type=%X Opcode=%X Op=%p\n",
 627                                 op_class, op_type, op->common.aml_opcode, op));
 628
 629                         status = AE_NOT_IMPLEMENTED;
 630                         break;
 631                 }
 632         }
 633
 634         /*
 635          * ACPI 2.0 support for 64-bit integers: Truncate numeric
 636          * result value if we are executing from a 32-bit ACPI table
 637          */
 638         acpi_ex_truncate_for32bit_table (walk_state->result_obj);
 639
 640         /*
 641          * Check if we just completed the evaluation of a
 642          * conditional predicate
 643          */
 644
 645         if ((ACPI_SUCCESS (status)) &&
 646                 (walk_state->control_state) &&
 647                 (walk_state->control_state->common.state ==
 648                         ACPI_CONTROL_PREDICATE_EXECUTING) &&
 649                 (walk_state->control_state->control.predicate_op == op)) {
 650                 status = acpi_ds_get_predicate_value (walk_state, walk_state->result_obj);
 651                 walk_state->result_obj = NULL;
 652         }
 653
 654
 655 cleanup:
 656
 657         /* Invoke exception handler on error */
 658
 659         if (ACPI_FAILURE (status) &&
 660                 acpi_gbl_exception_handler &&
 661                 !(status & AE_CODE_CONTROL)) {
 662                 acpi_ex_exit_interpreter ();
 663                 status = acpi_gbl_exception_handler (status,
 664                                  walk_state->method_node->name.integer, walk_state->opcode,
 665                                  walk_state->aml_offset, NULL);
 666                 acpi_ex_enter_interpreter ();
 667         }
 668
 669         if (walk_state->result_obj) {
 670                 /* Break to debugger to display result */
 671
 672                 ACPI_DEBUGGER_EXEC (acpi_db_display_result_object (walk_state->result_obj, walk_state));
 673
 674                 /*
 675                  * Delete the result op if and only if:
 676                  * Parent will not use the result -- such as any
 677                  * non-nested type2 op in a method (parent will be method)
 678                  */
 679                 acpi_ds_delete_result_if_not_used (op, walk_state->result_obj, walk_state);
 680         }
 681
 682 #ifdef _UNDER_DEVELOPMENT
 683
 684         if (walk_state->parser_state.aml == walk_state->parser_state.aml_end) {
 685                 acpi_db_method_end (walk_state);
 686         }
 687 #endif
 688
 689         /* Always clear the object stack */
 690
 691         walk_state->num_operands = 0;
 692
 693 #ifdef ACPI_DISASSEMBLER
 694
 695         /* On error, display method locals/args */
 696
 697         if (ACPI_FAILURE (status)) {
 698                 acpi_dm_dump_method_info (status, walk_state, op);
 699         }
 700 #endif
 701
 702         return_ACPI_STATUS (status);
 703 }
 704
 705