1 /****************************************************************************** 2 * 3 * Module Name: aslopt- Compiler optimizations 4 * 5 *****************************************************************************/ 6 7 /* 8 * Copyright (C) 2000 - 2022, 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 MERCHANTABILITY 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 #include "aslcompiler.h" 45 #include "aslcompiler.y.h" 46 47 #include "acparser.h" 48 #include "amlcode.h" 49 #include "acnamesp.h" 50 51 52 #define _COMPONENT ACPI_COMPILER 53 ACPI_MODULE_NAME ("aslopt") 54 55 56 static UINT32 OptTotal = 0; 57 58 /* Local prototypes */ 59 60 static ACPI_STATUS 61 OptSearchToRoot ( 62 ACPI_PARSE_OBJECT *Op, 63 ACPI_WALK_STATE *WalkState, 64 ACPI_NAMESPACE_NODE *CurrentNode, 65 ACPI_NAMESPACE_NODE *TargetNode, 66 ACPI_BUFFER *TargetPath, 67 char **NewPath); 68 69 static ACPI_STATUS 70 OptBuildShortestPath ( 71 ACPI_PARSE_OBJECT *Op, 72 ACPI_WALK_STATE *WalkState, 73 ACPI_NAMESPACE_NODE *CurrentNode, 74 ACPI_NAMESPACE_NODE *TargetNode, 75 ACPI_BUFFER *CurrentPath, 76 ACPI_BUFFER *TargetPath, 77 ACPI_SIZE AmlNameStringLength, 78 UINT8 IsDeclaration, 79 char **ReturnNewPath); 80 81 static ACPI_STATUS 82 OptOptimizeNameDeclaration ( 83 ACPI_PARSE_OBJECT *Op, 84 ACPI_WALK_STATE *WalkState, 85 ACPI_NAMESPACE_NODE *CurrentNode, 86 ACPI_NAMESPACE_NODE *TargetNode, 87 char *AmlNameString, 88 char **NewPath); 89 90 91 /******************************************************************************* 92 * 93 * FUNCTION: OptSearchToRoot 94 * 95 * PARAMETERS: Op - Current parser op 96 * WalkState - Current state 97 * CurrentNode - Where we are in the namespace 98 * TargetNode - Node to which we are referring 99 * TargetPath - External full path to the target node 100 * NewPath - Where the optimized path is returned 101 * 102 * RETURN: Status 103 * 104 * DESCRIPTION: Attempt to optimize a reference to a single 4-character ACPI 105 * name utilizing the search-to-root name resolution algorithm 106 * that is used by AML interpreters. 107 * 108 ******************************************************************************/ 109 110 static ACPI_STATUS 111 OptSearchToRoot ( 112 ACPI_PARSE_OBJECT *Op, 113 ACPI_WALK_STATE *WalkState, 114 ACPI_NAMESPACE_NODE *CurrentNode, 115 ACPI_NAMESPACE_NODE *TargetNode, 116 ACPI_BUFFER *TargetPath, 117 char **NewPath) 118 { 119 ACPI_NAMESPACE_NODE *Node; 120 ACPI_GENERIC_STATE ScopeInfo; 121 ACPI_STATUS Status; 122 char *Path; 123 124 125 ACPI_FUNCTION_NAME (OptSearchToRoot); 126 127 128 /* 129 * Check if search-to-root can be utilized. Use the last NameSeg of 130 * the NamePath and 1) See if can be found and 2) If found, make 131 * sure that it is the same node that we want. If there is another 132 * name in the search path before the one we want, the nodes will 133 * not match, and we cannot use this optimization. 134 */ 135 Path = &(((char *) TargetPath->Pointer)[ 136 TargetPath->Length - ACPI_NAMESEG_SIZE]); 137 ScopeInfo.Scope.Node = CurrentNode; 138 139 /* Lookup the NameSeg using SEARCH_PARENT (search-to-root) */ 140 141 Status = AcpiNsLookup (&ScopeInfo, Path, ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 142 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, 143 WalkState, &(Node)); 144 if (ACPI_FAILURE (Status)) 145 { 146 return (Status); 147 } 148 149 /* 150 * We found the name, but we must check to make sure that the node 151 * matches. Otherwise, there is another identical name in the search 152 * path that precludes the use of this optimization. 153 */ 154 if (Node != TargetNode) 155 { 156 /* 157 * This means that another object with the same name was found first, 158 * and we cannot use this optimization. 159 */ 160 return (AE_NOT_FOUND); 161 } 162 163 /* Found the node, we can use this optimization */ 164 165 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 166 "NAMESEG: %-24s", Path)); 167 168 /* We must allocate a new string for the name (TargetPath gets deleted) */ 169 170 *NewPath = UtLocalCacheCalloc (ACPI_NAMESEG_SIZE + 1); 171 strcpy (*NewPath, Path); 172 173 if (strncmp (*NewPath, "_T_", 3)) 174 { 175 AslError (ASL_OPTIMIZATION, ASL_MSG_SINGLE_NAME_OPTIMIZATION, 176 Op, *NewPath); 177 } 178 179 return (AE_OK); 180 } 181 182 183 /******************************************************************************* 184 * 185 * FUNCTION: OptBuildShortestPath 186 * 187 * PARAMETERS: Op - Current parser op 188 * WalkState - Current state 189 * CurrentNode - Where we are in the namespace 190 * TargetNode - Node to which we are referring 191 * CurrentPath - External full path to the current node 192 * TargetPath - External full path to the target node 193 * AmlNameStringLength - Length of the original namepath 194 * IsDeclaration - TRUE for declaration, FALSE for reference 195 * ReturnNewPath - Where the optimized path is returned 196 * 197 * RETURN: Status 198 * 199 * DESCRIPTION: Build an optimal NamePath using carats 200 * 201 ******************************************************************************/ 202 203 static ACPI_STATUS 204 OptBuildShortestPath ( 205 ACPI_PARSE_OBJECT *Op, 206 ACPI_WALK_STATE *WalkState, 207 ACPI_NAMESPACE_NODE *CurrentNode, 208 ACPI_NAMESPACE_NODE *TargetNode, 209 ACPI_BUFFER *CurrentPath, 210 ACPI_BUFFER *TargetPath, 211 ACPI_SIZE AmlNameStringLength, 212 UINT8 IsDeclaration, 213 char **ReturnNewPath) 214 { 215 UINT32 NumCommonSegments; 216 UINT32 MaxCommonSegments; 217 UINT32 Index; 218 UINT32 NumCarats; 219 UINT32 i; 220 char *NewPathInternal; 221 char *NewPathExternal; 222 ACPI_NAMESPACE_NODE *Node; 223 ACPI_GENERIC_STATE ScopeInfo; 224 ACPI_STATUS Status; 225 BOOLEAN SubPath = FALSE; 226 227 228 ACPI_FUNCTION_NAME (OptBuildShortestPath); 229 230 231 ScopeInfo.Scope.Node = CurrentNode; 232 233 /* 234 * Determine the maximum number of NameSegs that the Target and Current paths 235 * can possibly have in common. (To optimize, we have to have at least 1) 236 * 237 * Note: The external NamePath string lengths are always a multiple of 5 238 * (ACPI_NAMESEG_SIZE + separator) 239 */ 240 MaxCommonSegments = TargetPath->Length / ACPI_PATH_SEGMENT_LENGTH; 241 if (CurrentPath->Length < TargetPath->Length) 242 { 243 MaxCommonSegments = CurrentPath->Length / ACPI_PATH_SEGMENT_LENGTH; 244 } 245 246 /* 247 * Determine how many NameSegs the two paths have in common. 248 * (Starting from the root) 249 */ 250 for (NumCommonSegments = 0; 251 NumCommonSegments < MaxCommonSegments; 252 NumCommonSegments++) 253 { 254 /* Compare two single NameSegs */ 255 256 Index = (NumCommonSegments * ACPI_PATH_SEGMENT_LENGTH) + 1; 257 258 if (!ACPI_COMPARE_NAMESEG ( 259 &(ACPI_CAST_PTR (char, TargetPath->Pointer)) [Index], 260 &(ACPI_CAST_PTR (char, CurrentPath->Pointer)) [Index])) 261 { 262 /* Mismatch */ 263 264 break; 265 } 266 } 267 268 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " COMMON: %u", 269 NumCommonSegments)); 270 271 /* There must be at least 1 common NameSeg in order to optimize */ 272 273 if (NumCommonSegments == 0) 274 { 275 return (AE_NOT_FOUND); 276 } 277 278 if (NumCommonSegments == MaxCommonSegments) 279 { 280 if (CurrentPath->Length == TargetPath->Length) 281 { 282 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " SAME PATH")); 283 return (AE_NOT_FOUND); 284 } 285 else 286 { 287 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " SUBPATH")); 288 SubPath = TRUE; 289 } 290 } 291 292 /* Determine how many prefix Carats are required */ 293 294 NumCarats = (CurrentPath->Length / ACPI_PATH_SEGMENT_LENGTH) - 295 NumCommonSegments; 296 297 /* 298 * Construct a new target string 299 */ 300 NewPathExternal = 301 UtLocalCacheCalloc (TargetPath->Length + NumCarats + 1); 302 303 /* Insert the Carats into the Target string */ 304 305 for (i = 0; i < NumCarats; i++) 306 { 307 NewPathExternal[i] = AML_PARENT_PREFIX; 308 } 309 310 /* 311 * Copy only the necessary (optimal) segments from the original 312 * target string 313 */ 314 Index = (NumCommonSegments * ACPI_PATH_SEGMENT_LENGTH) + 1; 315 316 /* Special handling for exact subpath in a name declaration */ 317 318 if (IsDeclaration && SubPath && 319 (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] = AML_PARENT_PREFIX; 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 strcpy (&NewPathExternal[i], 346 &(ACPI_CAST_PTR (char, TargetPath->Pointer))[Index]); 347 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " %-24s", NewPathExternal)); 348 349 /* 350 * Internalize the new target string and check it against the original 351 * string to make sure that this is in fact an optimization. If the 352 * original string is already optimal, there is no point in continuing. 353 */ 354 Status = AcpiNsInternalizeName (NewPathExternal, &NewPathInternal); 355 if (ACPI_FAILURE (Status)) 356 { 357 AslCoreSubsystemError (Op, Status, "Internalizing new NamePath", 358 ASL_NO_ABORT); 359 goto Cleanup; 360 } 361 362 if (strlen (NewPathInternal) >= AmlNameStringLength) 363 { 364 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 365 " NOT SHORTER (New %u old %u)", 366 (UINT32) strlen (NewPathInternal), 367 (UINT32) AmlNameStringLength)); 368 369 ACPI_FREE (NewPathInternal); 370 Status = AE_NOT_FOUND; 371 goto Cleanup; 372 } 373 374 /* 375 * Check to make sure that the optimization finds the node we are 376 * looking for. This is simply a sanity check on the new 377 * path that has been created. 378 */ 379 Status = AcpiNsLookup (&ScopeInfo, NewPathInternal, 380 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 381 ACPI_NS_DONT_OPEN_SCOPE, WalkState, &(Node)); 382 if (ACPI_SUCCESS (Status)) 383 { 384 /* Found the namepath, but make sure the node is correct */ 385 386 if (Node == TargetNode) 387 { 388 /* The lookup matched the node, accept this optimization */ 389 390 AslError (ASL_OPTIMIZATION, ASL_MSG_NAME_OPTIMIZATION, 391 Op, NewPathExternal); 392 *ReturnNewPath = NewPathInternal; 393 } 394 else 395 { 396 /* Node is not correct, do not use this optimization */ 397 398 Status = AE_NOT_FOUND; 399 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ***** WRONG NODE")); 400 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 401 "Not using optimized name - found wrong node"); 402 } 403 } 404 else 405 { 406 /* The lookup failed, we obviously cannot use this optimization */ 407 408 ACPI_FREE (NewPathInternal); 409 410 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ***** NOT FOUND")); 411 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 412 "Not using optimized name - did not find node"); 413 } 414 415 Cleanup: 416 417 return (Status); 418 } 419 420 421 /******************************************************************************* 422 * 423 * FUNCTION: OptOptimizeNameDeclaration 424 * 425 * PARAMETERS: Op - Current parser op 426 * WalkState - Current state 427 * CurrentNode - Where we are in the namespace 428 * AmlNameString - Unoptimized namepath 429 * NewPath - Where the optimized path is returned 430 * 431 * RETURN: Status. AE_OK If path is optimized 432 * 433 * DESCRIPTION: Perform a simple optimization of removing an extraneous 434 * backslash prefix if we are already at the root scope. 435 * 436 ******************************************************************************/ 437 438 static ACPI_STATUS 439 OptOptimizeNameDeclaration ( 440 ACPI_PARSE_OBJECT *Op, 441 ACPI_WALK_STATE *WalkState, 442 ACPI_NAMESPACE_NODE *CurrentNode, 443 ACPI_NAMESPACE_NODE *TargetNode, 444 char *AmlNameString, 445 char **NewPath) 446 { 447 ACPI_STATUS Status; 448 char *NewPathExternal; 449 ACPI_NAMESPACE_NODE *Node; 450 451 452 ACPI_FUNCTION_TRACE (OptOptimizeNameDeclaration); 453 454 455 if (((CurrentNode == AcpiGbl_RootNode) || 456 (Op->Common.Parent->Asl.ParseOpcode == PARSEOP_DEFINITION_BLOCK)) && 457 (ACPI_IS_ROOT_PREFIX (AmlNameString[0]))) 458 { 459 /* 460 * The current scope is the root, and the namepath has a root prefix 461 * that is therefore extraneous. Remove it. 462 */ 463 *NewPath = &AmlNameString[1]; 464 465 /* Debug output */ 466 467 Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, *NewPath, 468 NULL, &NewPathExternal); 469 if (ACPI_FAILURE (Status)) 470 { 471 AslCoreSubsystemError (Op, Status, "Externalizing NamePath", 472 ASL_NO_ABORT); 473 return (Status); 474 } 475 476 /* 477 * Check to make sure that the optimization finds the node we are 478 * looking for. This is simply a sanity check on the new 479 * path that has been created. 480 * 481 * We know that we are at the root, so NULL is used for the scope. 482 */ 483 Status = AcpiNsLookup (NULL, *NewPath, 484 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 485 ACPI_NS_DONT_OPEN_SCOPE, WalkState, &(Node)); 486 if (ACPI_SUCCESS (Status)) 487 { 488 /* Found the namepath, but make sure the node is correct */ 489 490 if (Node == TargetNode) 491 { 492 /* The lookup matched the node, accept this optimization */ 493 494 AslError (ASL_OPTIMIZATION, ASL_MSG_NAME_OPTIMIZATION, 495 Op, NewPathExternal); 496 497 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 498 "AT ROOT: %-24s", NewPathExternal)); 499 } 500 else 501 { 502 /* Node is not correct, do not use this optimization */ 503 504 Status = AE_NOT_FOUND; 505 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 506 " ***** WRONG NODE")); 507 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 508 "Not using optimized name - found wrong node"); 509 } 510 } 511 else 512 { 513 /* The lookup failed, we obviously cannot use this optimization */ 514 515 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 516 " ***** NOT FOUND")); 517 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 518 "Not using optimized name - did not find node"); 519 } 520 521 ACPI_FREE (NewPathExternal); 522 return (Status); 523 } 524 525 /* Could not optimize */ 526 527 return (AE_NOT_FOUND); 528 } 529 530 531 /******************************************************************************* 532 * 533 * FUNCTION: OptOptimizeNamePath 534 * 535 * PARAMETERS: Op - Current parser op 536 * Flags - Opcode info flags 537 * WalkState - Current state 538 * AmlNameString - Unoptimized namepath 539 * TargetNode - Node to which AmlNameString refers 540 * 541 * RETURN: None. If path is optimized, the Op is updated with new path 542 * 543 * DESCRIPTION: Optimize a Named Declaration or Reference to the minimal length. 544 * Must take into account both the current location in the 545 * namespace and the actual reference path. 546 * 547 ******************************************************************************/ 548 549 void 550 OptOptimizeNamePath ( 551 ACPI_PARSE_OBJECT *Op, 552 UINT32 Flags, 553 ACPI_WALK_STATE *WalkState, 554 char *AmlNameString, 555 ACPI_NAMESPACE_NODE *TargetNode) 556 { 557 ACPI_STATUS Status; 558 ACPI_BUFFER TargetPath; 559 ACPI_BUFFER CurrentPath; 560 ACPI_SIZE AmlNameStringLength; 561 ACPI_NAMESPACE_NODE *CurrentNode; 562 char *ExternalNameString; 563 char *NewPath = NULL; 564 ACPI_SIZE HowMuchShorter; 565 ACPI_PARSE_OBJECT *NextOp; 566 567 568 ACPI_FUNCTION_TRACE (OptOptimizeNamePath); 569 570 571 /* This is an optional optimization */ 572 573 if (!AslGbl_ReferenceOptimizationFlag) 574 { 575 return_VOID; 576 } 577 578 /* Various required items */ 579 580 if (!TargetNode || !WalkState || !AmlNameString || !Op->Common.Parent) 581 { 582 return_VOID; 583 } 584 585 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 586 "PATH OPTIMIZE: Line %5d ParentOp [%12.12s] ThisOp [%12.12s] ", 587 Op->Asl.LogicalLineNumber, 588 AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), 589 AcpiPsGetOpcodeName (Op->Common.AmlOpcode))); 590 591 if (!(Flags & (AML_NAMED | AML_CREATE))) 592 { 593 if (Op->Asl.CompileFlags & OP_IS_NAME_DECLARATION) 594 { 595 /* We don't want to fuss with actual name declaration nodes here */ 596 597 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 598 "******* NAME DECLARATION\n")); 599 return_VOID; 600 } 601 } 602 603 /* 604 * The original path must be longer than one NameSeg (4 chars) for there 605 * to be any possibility that it can be optimized to a shorter string 606 */ 607 AmlNameStringLength = strlen (AmlNameString); 608 if (AmlNameStringLength <= ACPI_NAMESEG_SIZE) 609 { 610 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 611 "NAMESEG %4.4s\n", AmlNameString)); 612 return_VOID; 613 } 614 615 /* 616 * We need to obtain the node that represents the current scope -- where 617 * we are right now in the namespace. We will compare this path 618 * against the Namepath, looking for commonality. 619 */ 620 CurrentNode = AcpiGbl_RootNode; 621 if (WalkState->ScopeInfo) 622 { 623 CurrentNode = WalkState->ScopeInfo->Scope.Node; 624 } 625 626 if (Flags & (AML_NAMED | AML_CREATE)) 627 { 628 /* This is the declaration of a new name */ 629 630 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "NAME\n")); 631 632 /* 633 * The node of interest is the parent of this node (the containing 634 * scope). The actual namespace node may be up more than one level 635 * of parse op or it may not exist at all (if we traverse back 636 * up to the root.) 637 */ 638 NextOp = Op->Asl.Parent; 639 while (NextOp && (!NextOp->Asl.Node)) 640 { 641 NextOp = NextOp->Asl.Parent; 642 } 643 644 if (NextOp && NextOp->Asl.Node) 645 { 646 CurrentNode = NextOp->Asl.Node; 647 } 648 else 649 { 650 CurrentNode = AcpiGbl_RootNode; 651 } 652 } 653 else 654 { 655 /* This is a reference to an existing named object */ 656 657 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "REFERENCE\n")); 658 } 659 660 /* 661 * Obtain the full paths to the two nodes that we are interested in 662 * (Target and current namespace location) in external 663 * format -- something we can easily manipulate 664 */ 665 TargetPath.Length = ACPI_ALLOCATE_LOCAL_BUFFER; 666 Status = AcpiNsHandleToPathname (TargetNode, &TargetPath, FALSE); 667 if (ACPI_FAILURE (Status)) 668 { 669 AslCoreSubsystemError (Op, Status, "Getting Target NamePath", 670 ASL_NO_ABORT); 671 return_VOID; 672 } 673 674 TargetPath.Length--; /* Subtract one for null terminator */ 675 676 /* CurrentPath is the path to this scope (where we are in the namespace) */ 677 678 CurrentPath.Length = ACPI_ALLOCATE_LOCAL_BUFFER; 679 Status = AcpiNsHandleToPathname (CurrentNode, &CurrentPath, FALSE); 680 if (ACPI_FAILURE (Status)) 681 { 682 AslCoreSubsystemError (Op, Status, "Getting Current NamePath", 683 ASL_NO_ABORT); 684 return_VOID; 685 } 686 687 CurrentPath.Length--; /* Subtract one for null terminator */ 688 689 /* Debug output only */ 690 691 Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, AmlNameString, 692 NULL, &ExternalNameString); 693 if (ACPI_FAILURE (Status)) 694 { 695 AslCoreSubsystemError (Op, Status, "Externalizing NamePath", 696 ASL_NO_ABORT); 697 return_VOID; 698 } 699 700 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 701 "CURRENT SCOPE: (%2u) %-37s FULL PATH TO NAME: (%2u) %-32s ACTUAL AML:%-32s\n", 702 (UINT32) CurrentPath.Length, (char *) CurrentPath.Pointer, 703 (UINT32) TargetPath.Length, (char *) TargetPath.Pointer, 704 ExternalNameString)); 705 706 ACPI_FREE (ExternalNameString); 707 708 /* 709 * Attempt an optimization depending on the type of namepath 710 */ 711 if (Flags & (AML_NAMED | AML_CREATE)) 712 { 713 /* 714 * This is a named opcode and the namepath is a name declaration, not 715 * a reference. 716 */ 717 Status = OptOptimizeNameDeclaration (Op, WalkState, CurrentNode, 718 TargetNode, AmlNameString, &NewPath); 719 if (ACPI_FAILURE (Status)) 720 { 721 /* 722 * 2) now attempt to 723 * optimize the namestring with carats (up-arrow) 724 */ 725 Status = OptBuildShortestPath (Op, WalkState, CurrentNode, 726 TargetNode, &CurrentPath, &TargetPath, 727 AmlNameStringLength, 1, &NewPath); 728 } 729 } 730 else 731 { 732 /* 733 * This is a reference to an existing named object 734 * 735 * 1) Check if search-to-root can be utilized using the last 736 * NameSeg of the NamePath 737 */ 738 Status = OptSearchToRoot (Op, WalkState, CurrentNode, 739 TargetNode, &TargetPath, &NewPath); 740 if (ACPI_FAILURE (Status)) 741 { 742 /* 743 * 2) Search-to-root could not be used, now attempt to 744 * optimize the namestring with carats (up-arrow) 745 */ 746 Status = OptBuildShortestPath (Op, WalkState, CurrentNode, 747 TargetNode, &CurrentPath, &TargetPath, 748 AmlNameStringLength, 0, &NewPath); 749 } 750 } 751 752 /* 753 * Success from above indicates that the NamePath was successfully 754 * optimized. We need to update the parse op with the new name 755 */ 756 if (ACPI_SUCCESS (Status)) 757 { 758 HowMuchShorter = (AmlNameStringLength - strlen (NewPath)); 759 OptTotal += HowMuchShorter; 760 761 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 762 " REDUCED BY %2u (TOTAL SAVED %2u)", 763 (UINT32) HowMuchShorter, OptTotal)); 764 765 if (Flags & AML_NAMED) 766 { 767 if (Op->Asl.AmlOpcode == AML_ALIAS_OP) 768 { 769 /* 770 * ALIAS is the only oddball opcode, the name declaration 771 * (alias name) is the second operand 772 */ 773 Op->Asl.Child->Asl.Next->Asl.Value.String = NewPath; 774 Op->Asl.Child->Asl.Next->Asl.AmlLength = strlen (NewPath); 775 } 776 else 777 { 778 Op->Asl.Child->Asl.Value.String = NewPath; 779 Op->Asl.Child->Asl.AmlLength = strlen (NewPath); 780 } 781 } 782 else if (Flags & AML_CREATE) 783 { 784 /* Name must appear as the last parameter */ 785 786 NextOp = Op->Asl.Child; 787 while (!(NextOp->Asl.CompileFlags & OP_IS_NAME_DECLARATION)) 788 { 789 NextOp = NextOp->Asl.Next; 790 } 791 /* Update the parse node with the new NamePath */ 792 793 NextOp->Asl.Value.String = NewPath; 794 NextOp->Asl.AmlLength = strlen (NewPath); 795 } 796 else 797 { 798 /* Update the parse node with the new NamePath */ 799 800 Op->Asl.Value.String = NewPath; 801 Op->Asl.AmlLength = strlen (NewPath); 802 } 803 } 804 else 805 { 806 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ALREADY OPTIMAL")); 807 } 808 809 /* Cleanup path buffers */ 810 811 ACPI_FREE (TargetPath.Pointer); 812 ACPI_FREE (CurrentPath.Pointer); 813 814 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "\n")); 815 return_VOID; 816 } 817