1 /****************************************************************************** 2 * 3 * Module Name: aslopt- Compiler optimizations 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2012, 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 <contrib/dev/acpica/compiler/aslcompiler.h> 46 #include "aslcompiler.y.h" 47 48 #include <contrib/dev/acpica/include/acparser.h> 49 #include <contrib/dev/acpica/include/amlcode.h> 50 #include <contrib/dev/acpica/include/acnamesp.h> 51 52 53 #define _COMPONENT ACPI_COMPILER 54 ACPI_MODULE_NAME ("aslopt") 55 56 57 static UINT32 OptTotal = 0; 58 59 /* Local prototypes */ 60 61 static ACPI_STATUS 62 OptSearchToRoot ( 63 ACPI_PARSE_OBJECT *Op, 64 ACPI_WALK_STATE *WalkState, 65 ACPI_NAMESPACE_NODE *CurrentNode, 66 ACPI_NAMESPACE_NODE *TargetNode, 67 ACPI_BUFFER *TargetPath, 68 char **NewPath); 69 70 static ACPI_STATUS 71 OptBuildShortestPath ( 72 ACPI_PARSE_OBJECT *Op, 73 ACPI_WALK_STATE *WalkState, 74 ACPI_NAMESPACE_NODE *CurrentNode, 75 ACPI_NAMESPACE_NODE *TargetNode, 76 ACPI_BUFFER *CurrentPath, 77 ACPI_BUFFER *TargetPath, 78 ACPI_SIZE AmlNameStringLength, 79 UINT8 IsDeclaration, 80 char **ReturnNewPath); 81 82 static ACPI_STATUS 83 OptOptimizeNameDeclaration ( 84 ACPI_PARSE_OBJECT *Op, 85 ACPI_WALK_STATE *WalkState, 86 ACPI_NAMESPACE_NODE *CurrentNode, 87 ACPI_NAMESPACE_NODE *TargetNode, 88 char *AmlNameString, 89 char **NewPath); 90 91 92 /******************************************************************************* 93 * 94 * FUNCTION: OptSearchToRoot 95 * 96 * PARAMETERS: Op - Current parser op 97 * WalkState - Current state 98 * CurrentNode - Where we are in the namespace 99 * TargetNode - Node to which we are referring 100 * TargetPath - External full path to the target node 101 * NewPath - Where the optimized path is returned 102 * 103 * RETURN: Status 104 * 105 * DESCRIPTION: Attempt to optimize a reference to a single 4-character ACPI 106 * name utilizing the search-to-root name resolution algorithm 107 * that is used by AML interpreters. 108 * 109 ******************************************************************************/ 110 111 static ACPI_STATUS 112 OptSearchToRoot ( 113 ACPI_PARSE_OBJECT *Op, 114 ACPI_WALK_STATE *WalkState, 115 ACPI_NAMESPACE_NODE *CurrentNode, 116 ACPI_NAMESPACE_NODE *TargetNode, 117 ACPI_BUFFER *TargetPath, 118 char **NewPath) 119 { 120 ACPI_NAMESPACE_NODE *Node; 121 ACPI_GENERIC_STATE ScopeInfo; 122 ACPI_STATUS Status; 123 char *Path; 124 125 126 ACPI_FUNCTION_NAME (OptSearchToRoot); 127 128 129 /* 130 * Check if search-to-root can be utilized. Use the last NameSeg of 131 * the NamePath and 1) See if can be found and 2) If found, make 132 * sure that it is the same node that we want. If there is another 133 * name in the search path before the one we want, the nodes will 134 * not match, and we cannot use this optimization. 135 */ 136 Path = &(((char *) TargetPath->Pointer)[TargetPath->Length - 137 ACPI_NAME_SIZE]), 138 ScopeInfo.Scope.Node = CurrentNode; 139 140 /* Lookup the NameSeg using SEARCH_PARENT (search-to-root) */ 141 142 Status = AcpiNsLookup (&ScopeInfo, Path, ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 143 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, 144 WalkState, &(Node)); 145 if (ACPI_FAILURE (Status)) 146 { 147 return (Status); 148 } 149 150 /* 151 * We found the name, but we must check to make sure that the node 152 * matches. Otherwise, there is another identical name in the search 153 * path that precludes the use of this optimization. 154 */ 155 if (Node != TargetNode) 156 { 157 /* 158 * This means that another object with the same name was found first, 159 * and we cannot use this optimization. 160 */ 161 return (AE_NOT_FOUND); 162 } 163 164 /* Found the node, we can use this optimization */ 165 166 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 167 "NAMESEG: %-24s", Path)); 168 169 /* We must allocate a new string for the name (TargetPath gets deleted) */ 170 171 *NewPath = ACPI_ALLOCATE_ZEROED (ACPI_NAME_SIZE + 1); 172 ACPI_STRCPY (*NewPath, Path); 173 174 if (ACPI_STRNCMP (*NewPath, "_T_", 3)) 175 { 176 AslError (ASL_OPTIMIZATION, ASL_MSG_SINGLE_NAME_OPTIMIZATION, Op, 177 *NewPath); 178 } 179 180 return (AE_OK); 181 } 182 183 184 /******************************************************************************* 185 * 186 * FUNCTION: OptBuildShortestPath 187 * 188 * PARAMETERS: Op - Current parser op 189 * WalkState - Current state 190 * CurrentNode - Where we are in the namespace 191 * TargetNode - Node to which we are referring 192 * CurrentPath - External full path to the current node 193 * TargetPath - External full path to the target node 194 * AmlNameStringLength - Length of the original namepath 195 * IsDeclaration - TRUE for declaration, FALSE for reference 196 * ReturnNewPath - Where the optimized path is returned 197 * 198 * RETURN: Status 199 * 200 * DESCRIPTION: Build an optimal NamePath using carats 201 * 202 ******************************************************************************/ 203 204 static ACPI_STATUS 205 OptBuildShortestPath ( 206 ACPI_PARSE_OBJECT *Op, 207 ACPI_WALK_STATE *WalkState, 208 ACPI_NAMESPACE_NODE *CurrentNode, 209 ACPI_NAMESPACE_NODE *TargetNode, 210 ACPI_BUFFER *CurrentPath, 211 ACPI_BUFFER *TargetPath, 212 ACPI_SIZE AmlNameStringLength, 213 UINT8 IsDeclaration, 214 char **ReturnNewPath) 215 { 216 UINT32 NumCommonSegments; 217 UINT32 MaxCommonSegments; 218 UINT32 Index; 219 UINT32 NumCarats; 220 UINT32 i; 221 char *NewPath; 222 char *NewPathExternal; 223 ACPI_NAMESPACE_NODE *Node; 224 ACPI_GENERIC_STATE ScopeInfo; 225 ACPI_STATUS Status; 226 BOOLEAN SubPath = FALSE; 227 228 229 ACPI_FUNCTION_NAME (OptBuildShortestPath); 230 231 232 ScopeInfo.Scope.Node = CurrentNode; 233 234 /* 235 * Determine the maximum number of NameSegs that the Target and Current paths 236 * can possibly have in common. (To optimize, we have to have at least 1) 237 * 238 * Note: The external NamePath string lengths are always a multiple of 5 239 * (ACPI_NAME_SIZE + separator) 240 */ 241 MaxCommonSegments = TargetPath->Length / ACPI_PATH_SEGMENT_LENGTH; 242 if (CurrentPath->Length < TargetPath->Length) 243 { 244 MaxCommonSegments = CurrentPath->Length / ACPI_PATH_SEGMENT_LENGTH; 245 } 246 247 /* 248 * Determine how many NameSegs the two paths have in common. 249 * (Starting from the root) 250 */ 251 for (NumCommonSegments = 0; 252 NumCommonSegments < MaxCommonSegments; 253 NumCommonSegments++) 254 { 255 /* Compare two single NameSegs */ 256 257 if (!ACPI_COMPARE_NAME ( 258 &((char *) TargetPath->Pointer)[ 259 (NumCommonSegments * ACPI_PATH_SEGMENT_LENGTH) + 1], 260 &((char *) CurrentPath->Pointer)[ 261 (NumCommonSegments * ACPI_PATH_SEGMENT_LENGTH) + 1])) 262 { 263 /* Mismatch */ 264 265 break; 266 } 267 } 268 269 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " COMMON: %u", 270 NumCommonSegments)); 271 272 /* There must be at least 1 common NameSeg in order to optimize */ 273 274 if (NumCommonSegments == 0) 275 { 276 return (AE_NOT_FOUND); 277 } 278 279 if (NumCommonSegments == MaxCommonSegments) 280 { 281 if (CurrentPath->Length == TargetPath->Length) 282 { 283 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " SAME PATH")); 284 return (AE_NOT_FOUND); 285 } 286 else 287 { 288 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " SUBPATH")); 289 SubPath = TRUE; 290 } 291 } 292 293 /* Determine how many prefix Carats are required */ 294 295 NumCarats = (CurrentPath->Length / ACPI_PATH_SEGMENT_LENGTH) - 296 NumCommonSegments; 297 298 /* 299 * Construct a new target string 300 */ 301 NewPathExternal = ACPI_ALLOCATE_ZEROED ( 302 TargetPath->Length + NumCarats + 1); 303 304 /* Insert the Carats into the Target string */ 305 306 for (i = 0; i < NumCarats; i++) 307 { 308 NewPathExternal[i] = '^'; 309 } 310 311 /* 312 * Copy only the necessary (optimal) segments from the original 313 * target string 314 */ 315 Index = (NumCommonSegments * ACPI_PATH_SEGMENT_LENGTH) + 1; 316 317 /* Special handling for exact subpath in a name declaration */ 318 319 if (IsDeclaration && SubPath && (CurrentPath->Length > TargetPath->Length)) 320 { 321 /* 322 * The current path is longer than the target, and the target is a 323 * subpath of the current path. We must include one more NameSeg of 324 * the target path 325 */ 326 Index -= ACPI_PATH_SEGMENT_LENGTH; 327 328 /* Special handling for Scope() operator */ 329 330 if (Op->Asl.AmlOpcode == AML_SCOPE_OP) 331 { 332 NewPathExternal[i] = '^'; 333 i++; 334 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "(EXTRA ^)")); 335 } 336 } 337 338 /* Make sure we haven't gone off the end of the target path */ 339 340 if (Index > TargetPath->Length) 341 { 342 Index = TargetPath->Length; 343 } 344 345 ACPI_STRCPY (&NewPathExternal[i], &((char *) TargetPath->Pointer)[Index]); 346 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " %-24s", NewPathExternal)); 347 348 /* 349 * Internalize the new target string and check it against the original 350 * string to make sure that this is in fact an optimization. If the 351 * original string is already optimal, there is no point in continuing. 352 */ 353 Status = AcpiNsInternalizeName (NewPathExternal, &NewPath); 354 if (ACPI_FAILURE (Status)) 355 { 356 AslCoreSubsystemError (Op, Status, "Internalizing new NamePath", 357 ASL_NO_ABORT); 358 ACPI_FREE (NewPathExternal); 359 return (Status); 360 } 361 362 if (ACPI_STRLEN (NewPath) >= AmlNameStringLength) 363 { 364 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 365 " NOT SHORTER (New %u old %u)", 366 (UINT32) ACPI_STRLEN (NewPath), (UINT32) AmlNameStringLength)); 367 ACPI_FREE (NewPathExternal); 368 return (AE_NOT_FOUND); 369 } 370 371 /* 372 * Check to make sure that the optimization finds the node we are 373 * looking for. This is simply a sanity check on the new 374 * path that has been created. 375 */ 376 Status = AcpiNsLookup (&ScopeInfo, NewPath, 377 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 378 ACPI_NS_DONT_OPEN_SCOPE, WalkState, &(Node)); 379 if (ACPI_SUCCESS (Status)) 380 { 381 /* Found the namepath, but make sure the node is correct */ 382 383 if (Node == TargetNode) 384 { 385 /* The lookup matched the node, accept this optimization */ 386 387 AslError (ASL_OPTIMIZATION, ASL_MSG_NAME_OPTIMIZATION, 388 Op, NewPathExternal); 389 *ReturnNewPath = NewPath; 390 } 391 else 392 { 393 /* Node is not correct, do not use this optimization */ 394 395 Status = AE_NOT_FOUND; 396 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ***** WRONG NODE")); 397 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 398 "Not using optimized name - found wrong node"); 399 } 400 } 401 else 402 { 403 /* The lookup failed, we obviously cannot use this optimization */ 404 405 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ***** NOT FOUND")); 406 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 407 "Not using optimized name - did not find node"); 408 } 409 410 ACPI_FREE (NewPathExternal); 411 return (Status); 412 } 413 414 415 /******************************************************************************* 416 * 417 * FUNCTION: OptOptimizeNameDeclaration 418 * 419 * PARAMETERS: Op - Current parser op 420 * WalkState - Current state 421 * CurrentNode - Where we are in the namespace 422 * AmlNameString - Unoptimized namepath 423 * NewPath - Where the optimized path is returned 424 * 425 * RETURN: Status. AE_OK If path is optimized 426 * 427 * DESCRIPTION: Perform a simple optimization of removing an extraneous 428 * backslash prefix if we are already at the root scope. 429 * 430 ******************************************************************************/ 431 432 static ACPI_STATUS 433 OptOptimizeNameDeclaration ( 434 ACPI_PARSE_OBJECT *Op, 435 ACPI_WALK_STATE *WalkState, 436 ACPI_NAMESPACE_NODE *CurrentNode, 437 ACPI_NAMESPACE_NODE *TargetNode, 438 char *AmlNameString, 439 char **NewPath) 440 { 441 ACPI_STATUS Status; 442 char *NewPathExternal; 443 ACPI_NAMESPACE_NODE *Node; 444 445 446 ACPI_FUNCTION_TRACE (OptOptimizeNameDeclaration); 447 448 449 if (((CurrentNode == AcpiGbl_RootNode) || 450 (Op->Common.Parent->Asl.ParseOpcode == PARSEOP_DEFINITIONBLOCK)) && 451 (AmlNameString[0] == '\\')) 452 { 453 /* 454 * The current scope is the root, and the namepath has a root prefix 455 * that is therefore extraneous. Remove it. 456 */ 457 *NewPath = &AmlNameString[1]; 458 459 /* Debug output */ 460 461 Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, *NewPath, 462 NULL, &NewPathExternal); 463 if (ACPI_FAILURE (Status)) 464 { 465 AslCoreSubsystemError (Op, Status, "Externalizing NamePath", 466 ASL_NO_ABORT); 467 return (Status); 468 } 469 470 /* 471 * Check to make sure that the optimization finds the node we are 472 * looking for. This is simply a sanity check on the new 473 * path that has been created. 474 * 475 * We know that we are at the root, so NULL is used for the scope. 476 */ 477 Status = AcpiNsLookup (NULL, *NewPath, 478 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 479 ACPI_NS_DONT_OPEN_SCOPE, WalkState, &(Node)); 480 if (ACPI_SUCCESS (Status)) 481 { 482 /* Found the namepath, but make sure the node is correct */ 483 484 if (Node == TargetNode) 485 { 486 /* The lookup matched the node, accept this optimization */ 487 488 AslError (ASL_OPTIMIZATION, ASL_MSG_NAME_OPTIMIZATION, 489 Op, NewPathExternal); 490 491 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 492 "AT ROOT: %-24s", NewPathExternal)); 493 } 494 else 495 { 496 /* Node is not correct, do not use this optimization */ 497 498 Status = AE_NOT_FOUND; 499 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 500 " ***** WRONG NODE")); 501 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 502 "Not using optimized name - found wrong node"); 503 } 504 } 505 else 506 { 507 /* The lookup failed, we obviously cannot use this optimization */ 508 509 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 510 " ***** NOT FOUND")); 511 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 512 "Not using optimized name - did not find node"); 513 } 514 515 ACPI_FREE (NewPathExternal); 516 return (Status); 517 } 518 519 /* Could not optimize */ 520 521 return (AE_NOT_FOUND); 522 } 523 524 525 /******************************************************************************* 526 * 527 * FUNCTION: OptOptimizeNamePath 528 * 529 * PARAMETERS: Op - Current parser op 530 * Flags - Opcode info flags 531 * WalkState - Current state 532 * AmlNameString - Unoptimized namepath 533 * TargetNode - Node to which AmlNameString refers 534 * 535 * RETURN: None. If path is optimized, the Op is updated with new path 536 * 537 * DESCRIPTION: Optimize a Named Declaration or Reference to the minimal length. 538 * Must take into account both the current location in the 539 * namespace and the actual reference path. 540 * 541 ******************************************************************************/ 542 543 void 544 OptOptimizeNamePath ( 545 ACPI_PARSE_OBJECT *Op, 546 UINT32 Flags, 547 ACPI_WALK_STATE *WalkState, 548 char *AmlNameString, 549 ACPI_NAMESPACE_NODE *TargetNode) 550 { 551 ACPI_STATUS Status; 552 ACPI_BUFFER TargetPath; 553 ACPI_BUFFER CurrentPath; 554 ACPI_SIZE AmlNameStringLength; 555 ACPI_NAMESPACE_NODE *CurrentNode; 556 char *ExternalNameString; 557 char *NewPath = NULL; 558 ACPI_SIZE HowMuchShorter; 559 ACPI_PARSE_OBJECT *NextOp; 560 561 562 ACPI_FUNCTION_TRACE (OptOptimizeNamePath); 563 564 565 /* This is an optional optimization */ 566 567 if (!Gbl_ReferenceOptimizationFlag) 568 { 569 return_VOID; 570 } 571 572 /* Various required items */ 573 574 if (!TargetNode || !WalkState || !AmlNameString || !Op->Common.Parent) 575 { 576 return_VOID; 577 } 578 579 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "%5d [%12.12s] [%12.12s] ", 580 Op->Asl.LogicalLineNumber, 581 AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), 582 AcpiPsGetOpcodeName (Op->Common.AmlOpcode))); 583 584 if (!(Flags & (AML_NAMED | AML_CREATE))) 585 { 586 if (Op->Asl.CompileFlags & NODE_IS_NAME_DECLARATION) 587 { 588 /* We don't want to fuss with actual name declaration nodes here */ 589 590 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 591 "******* NAME DECLARATION\n")); 592 return_VOID; 593 } 594 } 595 596 /* 597 * The original path must be longer than one NameSeg (4 chars) for there 598 * to be any possibility that it can be optimized to a shorter string 599 */ 600 AmlNameStringLength = ACPI_STRLEN (AmlNameString); 601 if (AmlNameStringLength <= ACPI_NAME_SIZE) 602 { 603 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 604 "NAMESEG %4.4s\n", AmlNameString)); 605 return_VOID; 606 } 607 608 /* 609 * We need to obtain the node that represents the current scope -- where 610 * we are right now in the namespace. We will compare this path 611 * against the Namepath, looking for commonality. 612 */ 613 CurrentNode = AcpiGbl_RootNode; 614 if (WalkState->ScopeInfo) 615 { 616 CurrentNode = WalkState->ScopeInfo->Scope.Node; 617 } 618 619 if (Flags & (AML_NAMED | AML_CREATE)) 620 { 621 /* This is the declaration of a new name */ 622 623 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "NAME")); 624 625 /* 626 * The node of interest is the parent of this node (the containing 627 * scope). The actual namespace node may be up more than one level 628 * of parse op or it may not exist at all (if we traverse back 629 * up to the root.) 630 */ 631 NextOp = Op->Asl.Parent; 632 while (NextOp && (!NextOp->Asl.Node)) 633 { 634 NextOp = NextOp->Asl.Parent; 635 } 636 if (NextOp && NextOp->Asl.Node) 637 { 638 CurrentNode = NextOp->Asl.Node; 639 } 640 else 641 { 642 CurrentNode = AcpiGbl_RootNode; 643 } 644 } 645 else 646 { 647 /* This is a reference to an existing named object */ 648 649 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "REF ")); 650 } 651 652 /* 653 * Obtain the full paths to the two nodes that we are interested in 654 * (Target and current namespace location) in external 655 * format -- something we can easily manipulate 656 */ 657 TargetPath.Length = ACPI_ALLOCATE_LOCAL_BUFFER; 658 Status = AcpiNsHandleToPathname (TargetNode, &TargetPath); 659 if (ACPI_FAILURE (Status)) 660 { 661 AslCoreSubsystemError (Op, Status, "Getting Target NamePath", 662 ASL_NO_ABORT); 663 return_VOID; 664 } 665 TargetPath.Length--; /* Subtract one for null terminator */ 666 667 /* CurrentPath is the path to this scope (where we are in the namespace) */ 668 669 CurrentPath.Length = ACPI_ALLOCATE_LOCAL_BUFFER; 670 Status = AcpiNsHandleToPathname (CurrentNode, &CurrentPath); 671 if (ACPI_FAILURE (Status)) 672 { 673 AslCoreSubsystemError (Op, Status, "Getting Current NamePath", 674 ASL_NO_ABORT); 675 return_VOID; 676 } 677 CurrentPath.Length--; /* Subtract one for null terminator */ 678 679 /* Debug output only */ 680 681 Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, AmlNameString, 682 NULL, &ExternalNameString); 683 if (ACPI_FAILURE (Status)) 684 { 685 AslCoreSubsystemError (Op, Status, "Externalizing NamePath", 686 ASL_NO_ABORT); 687 return_VOID; 688 } 689 690 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 691 "%37s (%2u) ==> %-32s(%2u) %-32s", 692 (char *) CurrentPath.Pointer, (UINT32) CurrentPath.Length, 693 (char *) TargetPath.Pointer, (UINT32) TargetPath.Length, ExternalNameString)); 694 695 ACPI_FREE (ExternalNameString); 696 697 /* 698 * Attempt an optmization depending on the type of namepath 699 */ 700 if (Flags & (AML_NAMED | AML_CREATE)) 701 { 702 /* 703 * This is a named opcode and the namepath is a name declaration, not 704 * a reference. 705 */ 706 Status = OptOptimizeNameDeclaration (Op, WalkState, CurrentNode, 707 TargetNode, AmlNameString, &NewPath); 708 if (ACPI_FAILURE (Status)) 709 { 710 /* 711 * 2) now attempt to 712 * optimize the namestring with carats (up-arrow) 713 */ 714 Status = OptBuildShortestPath (Op, WalkState, CurrentNode, 715 TargetNode, &CurrentPath, &TargetPath, 716 AmlNameStringLength, 1, &NewPath); 717 } 718 } 719 else 720 { 721 /* 722 * This is a reference to an existing named object 723 * 724 * 1) Check if search-to-root can be utilized using the last 725 * NameSeg of the NamePath 726 */ 727 Status = OptSearchToRoot (Op, WalkState, CurrentNode, 728 TargetNode, &TargetPath, &NewPath); 729 if (ACPI_FAILURE (Status)) 730 { 731 /* 732 * 2) Search-to-root could not be used, now attempt to 733 * optimize the namestring with carats (up-arrow) 734 */ 735 Status = OptBuildShortestPath (Op, WalkState, CurrentNode, 736 TargetNode, &CurrentPath, &TargetPath, 737 AmlNameStringLength, 0, &NewPath); 738 } 739 } 740 741 /* 742 * Success from above indicates that the NamePath was successfully 743 * optimized. We need to update the parse op with the new name 744 */ 745 if (ACPI_SUCCESS (Status)) 746 { 747 HowMuchShorter = (AmlNameStringLength - ACPI_STRLEN (NewPath)); 748 OptTotal += HowMuchShorter; 749 750 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " REDUCED %2u (%u)", 751 (UINT32) HowMuchShorter, OptTotal)); 752 753 if (Flags & AML_NAMED) 754 { 755 if (Op->Asl.AmlOpcode == AML_ALIAS_OP) 756 { 757 /* 758 * ALIAS is the only oddball opcode, the name declaration 759 * (alias name) is the second operand 760 */ 761 Op->Asl.Child->Asl.Next->Asl.Value.String = NewPath; 762 Op->Asl.Child->Asl.Next->Asl.AmlLength = ACPI_STRLEN (NewPath); 763 } 764 else 765 { 766 Op->Asl.Child->Asl.Value.String = NewPath; 767 Op->Asl.Child->Asl.AmlLength = ACPI_STRLEN (NewPath); 768 } 769 } 770 else if (Flags & AML_CREATE) 771 { 772 /* Name must appear as the last parameter */ 773 774 NextOp = Op->Asl.Child; 775 while (!(NextOp->Asl.CompileFlags & NODE_IS_NAME_DECLARATION)) 776 { 777 NextOp = NextOp->Asl.Next; 778 } 779 /* Update the parse node with the new NamePath */ 780 781 NextOp->Asl.Value.String = NewPath; 782 NextOp->Asl.AmlLength = ACPI_STRLEN (NewPath); 783 } 784 else 785 { 786 /* Update the parse node with the new NamePath */ 787 788 Op->Asl.Value.String = NewPath; 789 Op->Asl.AmlLength = ACPI_STRLEN (NewPath); 790 } 791 } 792 else 793 { 794 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ALREADY OPTIMAL")); 795 } 796 797 /* Cleanup path buffers */ 798 799 ACPI_FREE (TargetPath.Pointer); 800 ACPI_FREE (CurrentPath.Pointer); 801 802 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "\n")); 803 return_VOID; 804 } 805