1 /****************************************************************************** 2 * 3 * Module Name: aslopt- Compiler optimizations 4 * 5 *****************************************************************************/ 6 7 /****************************************************************************** 8 * 9 * 1. Copyright Notice 10 * 11 * Some or all of this work - Copyright (c) 1999 - 2009, Intel Corp. 12 * All rights reserved. 13 * 14 * 2. License 15 * 16 * 2.1. This is your license from Intel Corp. under its intellectual property 17 * rights. You may have additional license terms from the party that provided 18 * you this software, covering your right to use that party's intellectual 19 * property rights. 20 * 21 * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a 22 * copy of the source code appearing in this file ("Covered Code") an 23 * irrevocable, perpetual, worldwide license under Intel's copyrights in the 24 * base code distributed originally by Intel ("Original Intel Code") to copy, 25 * make derivatives, distribute, use and display any portion of the Covered 26 * Code in any form, with the right to sublicense such rights; and 27 * 28 * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent 29 * license (with the right to sublicense), under only those claims of Intel 30 * patents that are infringed by the Original Intel Code, to make, use, sell, 31 * offer to sell, and import the Covered Code and derivative works thereof 32 * solely to the minimum extent necessary to exercise the above copyright 33 * license, and in no event shall the patent license extend to any additions 34 * to or modifications of the Original Intel Code. No other license or right 35 * is granted directly or by implication, estoppel or otherwise; 36 * 37 * The above copyright and patent license is granted only if the following 38 * conditions are met: 39 * 40 * 3. Conditions 41 * 42 * 3.1. Redistribution of Source with Rights to Further Distribute Source. 43 * Redistribution of source code of any substantial portion of the Covered 44 * Code or modification with rights to further distribute source must include 45 * the above Copyright Notice, the above License, this list of Conditions, 46 * and the following Disclaimer and Export Compliance provision. In addition, 47 * Licensee must cause all Covered Code to which Licensee contributes to 48 * contain a file documenting the changes Licensee made to create that Covered 49 * Code and the date of any change. Licensee must include in that file the 50 * documentation of any changes made by any predecessor Licensee. Licensee 51 * must include a prominent statement that the modification is derived, 52 * directly or indirectly, from Original Intel Code. 53 * 54 * 3.2. Redistribution of Source with no Rights to Further Distribute Source. 55 * Redistribution of source code of any substantial portion of the Covered 56 * Code or modification without rights to further distribute source must 57 * include the following Disclaimer and Export Compliance provision in the 58 * documentation and/or other materials provided with distribution. In 59 * addition, Licensee may not authorize further sublicense of source of any 60 * portion of the Covered Code, and must include terms to the effect that the 61 * license from Licensee to its licensee is limited to the intellectual 62 * property embodied in the software Licensee provides to its licensee, and 63 * not to intellectual property embodied in modifications its licensee may 64 * make. 65 * 66 * 3.3. Redistribution of Executable. Redistribution in executable form of any 67 * substantial portion of the Covered Code or modification must reproduce the 68 * above Copyright Notice, and the following Disclaimer and Export Compliance 69 * provision in the documentation and/or other materials provided with the 70 * distribution. 71 * 72 * 3.4. Intel retains all right, title, and interest in and to the Original 73 * Intel Code. 74 * 75 * 3.5. Neither the name Intel nor any other trademark owned or controlled by 76 * Intel shall be used in advertising or otherwise to promote the sale, use or 77 * other dealings in products derived from or relating to the Covered Code 78 * without prior written authorization from Intel. 79 * 80 * 4. Disclaimer and Export Compliance 81 * 82 * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED 83 * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE 84 * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, 85 * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY 86 * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY 87 * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A 88 * PARTICULAR PURPOSE. 89 * 90 * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES 91 * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR 92 * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, 93 * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY 94 * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL 95 * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS 96 * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY 97 * LIMITED REMEDY. 98 * 99 * 4.3. Licensee shall not export, either directly or indirectly, any of this 100 * software or system incorporating such software without first obtaining any 101 * required license or other approval from the U. S. Department of Commerce or 102 * any other agency or department of the United States Government. In the 103 * event Licensee exports any such software from the United States or 104 * re-exports any such software from a foreign destination, Licensee shall 105 * ensure that the distribution and export/re-export of the software is in 106 * compliance with all laws, regulations, orders, or other restrictions of the 107 * U.S. Export Administration Regulations. Licensee agrees that neither it nor 108 * any of its subsidiaries will export/re-export any technical data, process, 109 * software, or service, directly or indirectly, to any country for which the 110 * United States government or any agency thereof requires an export license, 111 * other governmental approval, or letter of assurance, without first obtaining 112 * such license, approval or letter. 113 * 114 *****************************************************************************/ 115 116 117 #include <contrib/dev/acpica/compiler/aslcompiler.h> 118 #include "aslcompiler.y.h" 119 120 #include <contrib/dev/acpica/include/acparser.h> 121 #include <contrib/dev/acpica/include/amlcode.h> 122 #include <contrib/dev/acpica/include/acnamesp.h> 123 124 125 #define _COMPONENT ACPI_COMPILER 126 ACPI_MODULE_NAME ("aslopt") 127 128 129 static UINT32 OptTotal = 0; 130 131 /* Local prototypes */ 132 133 static ACPI_STATUS 134 OptSearchToRoot ( 135 ACPI_PARSE_OBJECT *Op, 136 ACPI_WALK_STATE *WalkState, 137 ACPI_NAMESPACE_NODE *CurrentNode, 138 ACPI_NAMESPACE_NODE *TargetNode, 139 ACPI_BUFFER *TargetPath, 140 char **NewPath); 141 142 static ACPI_STATUS 143 OptBuildShortestPath ( 144 ACPI_PARSE_OBJECT *Op, 145 ACPI_WALK_STATE *WalkState, 146 ACPI_NAMESPACE_NODE *CurrentNode, 147 ACPI_NAMESPACE_NODE *TargetNode, 148 ACPI_BUFFER *CurrentPath, 149 ACPI_BUFFER *TargetPath, 150 ACPI_SIZE AmlNameStringLength, 151 UINT8 IsDeclaration, 152 char **ReturnNewPath); 153 154 static ACPI_STATUS 155 OptOptimizeNameDeclaration ( 156 ACPI_PARSE_OBJECT *Op, 157 ACPI_WALK_STATE *WalkState, 158 ACPI_NAMESPACE_NODE *CurrentNode, 159 ACPI_NAMESPACE_NODE *TargetNode, 160 char *AmlNameString, 161 char **NewPath); 162 163 164 /******************************************************************************* 165 * 166 * FUNCTION: OptSearchToRoot 167 * 168 * PARAMETERS: Op - Current parser op 169 * WalkState - Current state 170 * CurrentNode - Where we are in the namespace 171 * TargetNode - Node to which we are referring 172 * TargetPath - External full path to the target node 173 * NewPath - Where the optimized path is returned 174 * 175 * RETURN: Status 176 * 177 * DESCRIPTION: Attempt to optimize a reference to a single 4-character ACPI 178 * name utilizing the search-to-root name resolution algorithm 179 * that is used by AML interpreters. 180 * 181 ******************************************************************************/ 182 183 static ACPI_STATUS 184 OptSearchToRoot ( 185 ACPI_PARSE_OBJECT *Op, 186 ACPI_WALK_STATE *WalkState, 187 ACPI_NAMESPACE_NODE *CurrentNode, 188 ACPI_NAMESPACE_NODE *TargetNode, 189 ACPI_BUFFER *TargetPath, 190 char **NewPath) 191 { 192 ACPI_NAMESPACE_NODE *Node; 193 ACPI_GENERIC_STATE ScopeInfo; 194 ACPI_STATUS Status; 195 char *Path; 196 197 198 ACPI_FUNCTION_NAME (OptSearchToRoot); 199 200 201 /* 202 * Check if search-to-root can be utilized. Use the last NameSeg of 203 * the NamePath and 1) See if can be found and 2) If found, make 204 * sure that it is the same node that we want. If there is another 205 * name in the search path before the one we want, the nodes will 206 * not match, and we cannot use this optimization. 207 */ 208 Path = &(((char *) TargetPath->Pointer)[TargetPath->Length - 209 ACPI_NAME_SIZE]), 210 ScopeInfo.Scope.Node = CurrentNode; 211 212 /* Lookup the NameSeg using SEARCH_PARENT (search-to-root) */ 213 214 Status = AcpiNsLookup (&ScopeInfo, Path, ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 215 ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE, 216 WalkState, &(Node)); 217 if (ACPI_FAILURE (Status)) 218 { 219 return (Status); 220 } 221 222 /* 223 * We found the name, but we must check to make sure that the node 224 * matches. Otherwise, there is another identical name in the search 225 * path that precludes the use of this optimization. 226 */ 227 if (Node != TargetNode) 228 { 229 /* 230 * This means that another object with the same name was found first, 231 * and we cannot use this optimization. 232 */ 233 return (AE_NOT_FOUND); 234 } 235 236 /* Found the node, we can use this optimization */ 237 238 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 239 "NAMESEG: %-24s", Path)); 240 241 /* We must allocate a new string for the name (TargetPath gets deleted) */ 242 243 *NewPath = ACPI_ALLOCATE_ZEROED (ACPI_NAME_SIZE + 1); 244 ACPI_STRCPY (*NewPath, Path); 245 246 if (ACPI_STRNCMP (*NewPath, "_T_", 3)) 247 { 248 AslError (ASL_OPTIMIZATION, ASL_MSG_SINGLE_NAME_OPTIMIZATION, Op, 249 *NewPath); 250 } 251 252 return (AE_OK); 253 } 254 255 256 /******************************************************************************* 257 * 258 * FUNCTION: OptBuildShortestPath 259 * 260 * PARAMETERS: Op - Current parser op 261 * WalkState - Current state 262 * CurrentNode - Where we are in the namespace 263 * TargetNode - Node to which we are referring 264 * CurrentPath - External full path to the current node 265 * TargetPath - External full path to the target node 266 * AmlNameStringLength - Length of the original namepath 267 * IsDeclaration - TRUE for declaration, FALSE for reference 268 * ReturnNewPath - Where the optimized path is returned 269 * 270 * RETURN: Status 271 * 272 * DESCRIPTION: Build an optimal NamePath using carats 273 * 274 ******************************************************************************/ 275 276 static ACPI_STATUS 277 OptBuildShortestPath ( 278 ACPI_PARSE_OBJECT *Op, 279 ACPI_WALK_STATE *WalkState, 280 ACPI_NAMESPACE_NODE *CurrentNode, 281 ACPI_NAMESPACE_NODE *TargetNode, 282 ACPI_BUFFER *CurrentPath, 283 ACPI_BUFFER *TargetPath, 284 ACPI_SIZE AmlNameStringLength, 285 UINT8 IsDeclaration, 286 char **ReturnNewPath) 287 { 288 UINT32 NumCommonSegments; 289 UINT32 MaxCommonSegments; 290 UINT32 Index; 291 UINT32 NumCarats; 292 UINT32 i; 293 char *NewPath; 294 char *NewPathExternal; 295 ACPI_NAMESPACE_NODE *Node; 296 ACPI_GENERIC_STATE ScopeInfo; 297 ACPI_STATUS Status; 298 BOOLEAN SubPath = FALSE; 299 300 301 ACPI_FUNCTION_NAME (OptBuildShortestPath); 302 303 304 ScopeInfo.Scope.Node = CurrentNode; 305 306 /* 307 * Determine the maximum number of NameSegs that the Target and Current paths 308 * can possibly have in common. (To optimize, we have to have at least 1) 309 * 310 * Note: The external NamePath string lengths are always a multiple of 5 311 * (ACPI_NAME_SIZE + separator) 312 */ 313 MaxCommonSegments = TargetPath->Length / ACPI_PATH_SEGMENT_LENGTH; 314 if (CurrentPath->Length < TargetPath->Length) 315 { 316 MaxCommonSegments = CurrentPath->Length / ACPI_PATH_SEGMENT_LENGTH; 317 } 318 319 /* 320 * Determine how many NameSegs the two paths have in common. 321 * (Starting from the root) 322 */ 323 for (NumCommonSegments = 0; 324 NumCommonSegments < MaxCommonSegments; 325 NumCommonSegments++) 326 { 327 /* Compare two single NameSegs */ 328 329 if (ACPI_STRNCMP ( 330 &((char *) TargetPath->Pointer)[(NumCommonSegments * 331 ACPI_PATH_SEGMENT_LENGTH) + 1], 332 &((char *) CurrentPath->Pointer)[(NumCommonSegments * 333 ACPI_PATH_SEGMENT_LENGTH) + 1], 334 ACPI_NAME_SIZE)) 335 { 336 /* Mismatch */ 337 338 break; 339 } 340 } 341 342 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " COMMON: %d", 343 NumCommonSegments)); 344 345 /* There must be at least 1 common NameSeg in order to optimize */ 346 347 if (NumCommonSegments == 0) 348 { 349 return (AE_NOT_FOUND); 350 } 351 352 if (NumCommonSegments == MaxCommonSegments) 353 { 354 if (CurrentPath->Length == TargetPath->Length) 355 { 356 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " SAME PATH")); 357 return (AE_NOT_FOUND); 358 } 359 else 360 { 361 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " SUBPATH")); 362 SubPath = TRUE; 363 } 364 } 365 366 /* Determine how many prefix Carats are required */ 367 368 NumCarats = (CurrentPath->Length / ACPI_PATH_SEGMENT_LENGTH) - 369 NumCommonSegments; 370 371 /* 372 * Construct a new target string 373 */ 374 NewPathExternal = ACPI_ALLOCATE_ZEROED ( 375 TargetPath->Length + NumCarats + 1); 376 377 /* Insert the Carats into the Target string */ 378 379 for (i = 0; i < NumCarats; i++) 380 { 381 NewPathExternal[i] = '^'; 382 } 383 384 /* 385 * Copy only the necessary (optimal) segments from the original 386 * target string 387 */ 388 Index = (NumCommonSegments * ACPI_PATH_SEGMENT_LENGTH) + 1; 389 390 /* Special handling for exact subpath in a name declaration */ 391 392 if (IsDeclaration && SubPath && (CurrentPath->Length > TargetPath->Length)) 393 { 394 /* 395 * The current path is longer than the target, and the target is a 396 * subpath of the current path. We must include one more NameSeg of 397 * the target path 398 */ 399 Index -= ACPI_PATH_SEGMENT_LENGTH; 400 401 /* Special handling for Scope() operator */ 402 403 if (Op->Asl.AmlOpcode == AML_SCOPE_OP) 404 { 405 NewPathExternal[i] = '^'; 406 i++; 407 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "(EXTRA ^)")); 408 } 409 } 410 411 /* Make sure we haven't gone off the end of the target path */ 412 413 if (Index > TargetPath->Length) 414 { 415 Index = TargetPath->Length; 416 } 417 418 ACPI_STRCPY (&NewPathExternal[i], &((char *) TargetPath->Pointer)[Index]); 419 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " %-24s", NewPathExternal)); 420 421 /* 422 * Internalize the new target string and check it against the original 423 * string to make sure that this is in fact an optimization. If the 424 * original string is already optimal, there is no point in continuing. 425 */ 426 Status = AcpiNsInternalizeName (NewPathExternal, &NewPath); 427 if (ACPI_FAILURE (Status)) 428 { 429 AslCoreSubsystemError (Op, Status, "Internalizing new NamePath", 430 ASL_NO_ABORT); 431 ACPI_FREE (NewPathExternal); 432 return (Status); 433 } 434 435 if (ACPI_STRLEN (NewPath) >= AmlNameStringLength) 436 { 437 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 438 " NOT SHORTER (New %u old %u)", 439 (UINT32) ACPI_STRLEN (NewPath), (UINT32) AmlNameStringLength)); 440 ACPI_FREE (NewPathExternal); 441 return (AE_NOT_FOUND); 442 } 443 444 /* 445 * Check to make sure that the optimization finds the node we are 446 * looking for. This is simply a sanity check on the new 447 * path that has been created. 448 */ 449 Status = AcpiNsLookup (&ScopeInfo, NewPath, 450 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 451 ACPI_NS_DONT_OPEN_SCOPE, WalkState, &(Node)); 452 if (ACPI_SUCCESS (Status)) 453 { 454 /* Found the namepath, but make sure the node is correct */ 455 456 if (Node == TargetNode) 457 { 458 /* The lookup matched the node, accept this optimization */ 459 460 AslError (ASL_OPTIMIZATION, ASL_MSG_NAME_OPTIMIZATION, 461 Op, NewPathExternal); 462 *ReturnNewPath = NewPath; 463 } 464 else 465 { 466 /* Node is not correct, do not use this optimization */ 467 468 Status = AE_NOT_FOUND; 469 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ***** WRONG NODE")); 470 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 471 "Not using optimized name - found wrong node"); 472 } 473 } 474 else 475 { 476 /* The lookup failed, we obviously cannot use this optimization */ 477 478 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ***** NOT FOUND")); 479 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 480 "Not using optimized name - did not find node"); 481 } 482 483 ACPI_FREE (NewPathExternal); 484 return (Status); 485 } 486 487 488 /******************************************************************************* 489 * 490 * FUNCTION: OptOptimizeNameDeclaration 491 * 492 * PARAMETERS: Op - Current parser op 493 * WalkState - Current state 494 * CurrentNode - Where we are in the namespace 495 * AmlNameString - Unoptimized namepath 496 * NewPath - Where the optimized path is returned 497 * 498 * RETURN: Status. AE_OK If path is optimized 499 * 500 * DESCRIPTION: Perform a simple optimization of removing an extraneous 501 * backslash prefix if we are already at the root scope. 502 * 503 ******************************************************************************/ 504 505 static ACPI_STATUS 506 OptOptimizeNameDeclaration ( 507 ACPI_PARSE_OBJECT *Op, 508 ACPI_WALK_STATE *WalkState, 509 ACPI_NAMESPACE_NODE *CurrentNode, 510 ACPI_NAMESPACE_NODE *TargetNode, 511 char *AmlNameString, 512 char **NewPath) 513 { 514 ACPI_STATUS Status; 515 char *NewPathExternal; 516 ACPI_GENERIC_STATE ScopeInfo; 517 ACPI_NAMESPACE_NODE *Node; 518 519 520 ACPI_FUNCTION_TRACE (OptOptimizeNameDeclaration); 521 522 523 if (((CurrentNode == AcpiGbl_RootNode) || 524 (Op->Common.Parent->Asl.ParseOpcode == PARSEOP_DEFINITIONBLOCK)) && 525 (AmlNameString[0] == '\\')) 526 { 527 /* 528 * The current scope is the root, and the namepath has a root prefix 529 * that is therefore extraneous. Remove it. 530 */ 531 *NewPath = &AmlNameString[1]; 532 533 /* Debug output */ 534 535 Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, *NewPath, 536 NULL, &NewPathExternal); 537 if (ACPI_FAILURE (Status)) 538 { 539 AslCoreSubsystemError (Op, Status, "Externalizing NamePath", 540 ASL_NO_ABORT); 541 return (Status); 542 } 543 544 /* 545 * Check to make sure that the optimization finds the node we are 546 * looking for. This is simply a sanity check on the new 547 * path that has been created. 548 */ 549 ScopeInfo.Scope.Node = CurrentNode; 550 Status = AcpiNsLookup (&ScopeInfo, *NewPath, 551 ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE, 552 ACPI_NS_DONT_OPEN_SCOPE, WalkState, &(Node)); 553 if (ACPI_SUCCESS (Status)) 554 { 555 /* Found the namepath, but make sure the node is correct */ 556 557 if (Node == TargetNode) 558 { 559 /* The lookup matched the node, accept this optimization */ 560 561 AslError (ASL_OPTIMIZATION, ASL_MSG_NAME_OPTIMIZATION, 562 Op, NewPathExternal); 563 564 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 565 "AT ROOT: %-24s", NewPathExternal)); 566 } 567 else 568 { 569 /* Node is not correct, do not use this optimization */ 570 571 Status = AE_NOT_FOUND; 572 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 573 " ***** WRONG NODE")); 574 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 575 "Not using optimized name - found wrong node"); 576 } 577 } 578 else 579 { 580 /* The lookup failed, we obviously cannot use this optimization */ 581 582 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 583 " ***** NOT FOUND")); 584 AslError (ASL_WARNING, ASL_MSG_COMPILER_INTERNAL, Op, 585 "Not using optimized name - did not find node"); 586 } 587 588 ACPI_FREE (NewPathExternal); 589 return (Status); 590 } 591 592 /* Could not optimize */ 593 594 return (AE_NOT_FOUND); 595 } 596 597 598 /******************************************************************************* 599 * 600 * FUNCTION: OptOptimizeNamePath 601 * 602 * PARAMETERS: Op - Current parser op 603 * Flags - Opcode info flags 604 * WalkState - Current state 605 * AmlNameString - Unoptimized namepath 606 * TargetNode - Node to which AmlNameString refers 607 * 608 * RETURN: None. If path is optimized, the Op is updated with new path 609 * 610 * DESCRIPTION: Optimize a Named Declaration or Reference to the minimal length. 611 * Must take into account both the current location in the 612 * namespace and the actual reference path. 613 * 614 ******************************************************************************/ 615 616 void 617 OptOptimizeNamePath ( 618 ACPI_PARSE_OBJECT *Op, 619 UINT32 Flags, 620 ACPI_WALK_STATE *WalkState, 621 char *AmlNameString, 622 ACPI_NAMESPACE_NODE *TargetNode) 623 { 624 ACPI_STATUS Status; 625 ACPI_BUFFER TargetPath; 626 ACPI_BUFFER CurrentPath; 627 ACPI_SIZE AmlNameStringLength; 628 ACPI_NAMESPACE_NODE *CurrentNode; 629 char *ExternalNameString; 630 char *NewPath = NULL; 631 ACPI_SIZE HowMuchShorter; 632 ACPI_PARSE_OBJECT *NextOp; 633 634 635 ACPI_FUNCTION_TRACE (OptOptimizeNamePath); 636 637 638 /* This is an optional optimization */ 639 640 if (!Gbl_ReferenceOptimizationFlag) 641 { 642 return_VOID; 643 } 644 645 /* Various required items */ 646 647 if (!TargetNode || !WalkState || !AmlNameString || !Op->Common.Parent) 648 { 649 return_VOID; 650 } 651 652 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "%5d [%12.12s] [%12.12s] ", 653 Op->Asl.LogicalLineNumber, 654 AcpiPsGetOpcodeName (Op->Common.Parent->Common.AmlOpcode), 655 AcpiPsGetOpcodeName (Op->Common.AmlOpcode))); 656 657 if (!(Flags & (AML_NAMED | AML_CREATE))) 658 { 659 if (Op->Asl.CompileFlags & NODE_IS_NAME_DECLARATION) 660 { 661 /* We don't want to fuss with actual name declaration nodes here */ 662 663 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 664 "******* NAME DECLARATION\n")); 665 return_VOID; 666 } 667 } 668 669 /* 670 * The original path must be longer than one NameSeg (4 chars) for there 671 * to be any possibility that it can be optimized to a shorter string 672 */ 673 AmlNameStringLength = ACPI_STRLEN (AmlNameString); 674 if (AmlNameStringLength <= ACPI_NAME_SIZE) 675 { 676 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 677 "NAMESEG %4.4s\n", AmlNameString)); 678 return_VOID; 679 } 680 681 /* 682 * We need to obtain the node that represents the current scope -- where 683 * we are right now in the namespace. We will compare this path 684 * against the Namepath, looking for commonality. 685 */ 686 CurrentNode = AcpiGbl_RootNode; 687 if (WalkState->ScopeInfo) 688 { 689 CurrentNode = WalkState->ScopeInfo->Scope.Node; 690 } 691 692 if (Flags & (AML_NAMED | AML_CREATE)) 693 { 694 /* This is the declaration of a new name */ 695 696 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "NAME")); 697 698 /* 699 * The node of interest is the parent of this node 700 * (the containing scope) 701 */ 702 CurrentNode = Op->Asl.Parent->Asl.Node; 703 if (!CurrentNode) 704 { 705 CurrentNode = AcpiGbl_RootNode; 706 } 707 } 708 else 709 { 710 /* This is a reference to an existing named object */ 711 712 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "REF ")); 713 } 714 715 /* 716 * Obtain the full paths to the two nodes that we are interested in 717 * (Target and current namespace location) in external 718 * format -- something we can easily manipulate 719 */ 720 TargetPath.Length = ACPI_ALLOCATE_LOCAL_BUFFER; 721 Status = AcpiNsHandleToPathname (TargetNode, &TargetPath); 722 if (ACPI_FAILURE (Status)) 723 { 724 AslCoreSubsystemError (Op, Status, "Getting Target NamePath", 725 ASL_NO_ABORT); 726 return_VOID; 727 } 728 TargetPath.Length--; /* Subtract one for null terminator */ 729 730 /* CurrentPath is the path to this scope (where we are in the namespace) */ 731 732 CurrentPath.Length = ACPI_ALLOCATE_LOCAL_BUFFER; 733 Status = AcpiNsHandleToPathname (CurrentNode, &CurrentPath); 734 if (ACPI_FAILURE (Status)) 735 { 736 AslCoreSubsystemError (Op, Status, "Getting Current NamePath", 737 ASL_NO_ABORT); 738 return_VOID; 739 } 740 CurrentPath.Length--; /* Subtract one for null terminator */ 741 742 /* Debug output only */ 743 744 Status = AcpiNsExternalizeName (ACPI_UINT32_MAX, AmlNameString, 745 NULL, &ExternalNameString); 746 if (ACPI_FAILURE (Status)) 747 { 748 AslCoreSubsystemError (Op, Status, "Externalizing NamePath", 749 ASL_NO_ABORT); 750 return_VOID; 751 } 752 753 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, 754 "%37s (%2u) ==> %-32s(%2u) %-32s", 755 (char *) CurrentPath.Pointer, (UINT32) CurrentPath.Length, 756 (char *) TargetPath.Pointer, (UINT32) TargetPath.Length, ExternalNameString)); 757 758 ACPI_FREE (ExternalNameString); 759 760 /* 761 * Attempt an optmization depending on the type of namepath 762 */ 763 if (Flags & (AML_NAMED | AML_CREATE)) 764 { 765 /* 766 * This is a named opcode and the namepath is a name declaration, not 767 * a reference. 768 */ 769 Status = OptOptimizeNameDeclaration (Op, WalkState, CurrentNode, 770 TargetNode, AmlNameString, &NewPath); 771 if (ACPI_FAILURE (Status)) 772 { 773 /* 774 * 2) now attempt to 775 * optimize the namestring with carats (up-arrow) 776 */ 777 Status = OptBuildShortestPath (Op, WalkState, CurrentNode, 778 TargetNode, &CurrentPath, &TargetPath, 779 AmlNameStringLength, 1, &NewPath); 780 } 781 } 782 else 783 { 784 /* 785 * This is a reference to an existing named object 786 * 787 * 1) Check if search-to-root can be utilized using the last 788 * NameSeg of the NamePath 789 */ 790 Status = OptSearchToRoot (Op, WalkState, CurrentNode, 791 TargetNode, &TargetPath, &NewPath); 792 if (ACPI_FAILURE (Status)) 793 { 794 /* 795 * 2) Search-to-root could not be used, now attempt to 796 * optimize the namestring with carats (up-arrow) 797 */ 798 Status = OptBuildShortestPath (Op, WalkState, CurrentNode, 799 TargetNode, &CurrentPath, &TargetPath, 800 AmlNameStringLength, 0, &NewPath); 801 } 802 } 803 804 /* 805 * Success from above indicates that the NamePath was successfully 806 * optimized. We need to update the parse op with the new name 807 */ 808 if (ACPI_SUCCESS (Status)) 809 { 810 HowMuchShorter = (AmlNameStringLength - ACPI_STRLEN (NewPath)); 811 OptTotal += HowMuchShorter; 812 813 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " REDUCED %2u (%u)", 814 (UINT32) HowMuchShorter, OptTotal)); 815 816 if (Flags & AML_NAMED) 817 { 818 if (Op->Asl.AmlOpcode == AML_ALIAS_OP) 819 { 820 /* 821 * ALIAS is the only oddball opcode, the name declaration 822 * (alias name) is the second operand 823 */ 824 Op->Asl.Child->Asl.Next->Asl.Value.String = NewPath; 825 Op->Asl.Child->Asl.Next->Asl.AmlLength = ACPI_STRLEN (NewPath); 826 } 827 else 828 { 829 Op->Asl.Child->Asl.Value.String = NewPath; 830 Op->Asl.Child->Asl.AmlLength = ACPI_STRLEN (NewPath); 831 } 832 } 833 else if (Flags & AML_CREATE) 834 { 835 /* Name must appear as the last parameter */ 836 837 NextOp = Op->Asl.Child; 838 while (!(NextOp->Asl.CompileFlags & NODE_IS_NAME_DECLARATION)) 839 { 840 NextOp = NextOp->Asl.Next; 841 } 842 /* Update the parse node with the new NamePath */ 843 844 NextOp->Asl.Value.String = NewPath; 845 NextOp->Asl.AmlLength = ACPI_STRLEN (NewPath); 846 } 847 else 848 { 849 /* Update the parse node with the new NamePath */ 850 851 Op->Asl.Value.String = NewPath; 852 Op->Asl.AmlLength = ACPI_STRLEN (NewPath); 853 } 854 } 855 else 856 { 857 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, " ALREADY OPTIMAL")); 858 } 859 860 /* Cleanup path buffers */ 861 862 ACPI_FREE (TargetPath.Pointer); 863 ACPI_FREE (CurrentPath.Pointer); 864 865 ACPI_DEBUG_PRINT_RAW ((ACPI_DB_OPTIMIZATIONS, "\n")); 866 return_VOID; 867 } 868 869