Douglas Gregor | a6b00fc | 2013-01-23 22:38:11 +0000 | [diff] [blame] | 1 | //===--- GlobalModuleIndex.cpp - Global Module Index ------------*- C++ -*-===// |
| 2 | // |
| 3 | // The LLVM Compiler Infrastructure |
| 4 | // |
| 5 | // This file is distributed under the University of Illinois Open Source |
| 6 | // License. See LICENSE.TXT for details. |
| 7 | // |
| 8 | //===----------------------------------------------------------------------===// |
| 9 | // |
| 10 | // This file implements the GlobalModuleIndex class. |
| 11 | // |
| 12 | //===----------------------------------------------------------------------===// |
| 13 | |
| 14 | #include "ASTReaderInternals.h" |
| 15 | #include "clang/Basic/FileManager.h" |
| 16 | #include "clang/Basic/OnDiskHashTable.h" |
| 17 | #include "clang/Serialization/ASTBitCodes.h" |
| 18 | #include "clang/Serialization/GlobalModuleIndex.h" |
| 19 | #include "llvm/ADT/DenseMap.h" |
| 20 | #include "llvm/ADT/MapVector.h" |
| 21 | #include "llvm/ADT/SmallString.h" |
| 22 | #include "llvm/ADT/StringExtras.h" |
| 23 | #include "llvm/Bitcode/BitstreamReader.h" |
| 24 | #include "llvm/Bitcode/BitstreamWriter.h" |
Douglas Gregor | 5100135 | 2013-01-23 22:45:24 +0000 | [diff] [blame] | 25 | #include "llvm/Support/FileSystem.h" |
Douglas Gregor | a6b00fc | 2013-01-23 22:38:11 +0000 | [diff] [blame] | 26 | #include "llvm/Support/LockFileManager.h" |
| 27 | #include "llvm/Support/MemoryBuffer.h" |
| 28 | #include "llvm/Support/PathV2.h" |
| 29 | using namespace clang; |
| 30 | using namespace serialization; |
| 31 | |
| 32 | //----------------------------------------------------------------------------// |
| 33 | // Shared constants |
| 34 | //----------------------------------------------------------------------------// |
| 35 | namespace { |
| 36 | enum { |
| 37 | /// \brief The block containing the index. |
| 38 | GLOBAL_INDEX_BLOCK_ID = llvm::bitc::FIRST_APPLICATION_BLOCKID |
| 39 | }; |
| 40 | |
| 41 | /// \brief Describes the record types in the index. |
| 42 | enum IndexRecordTypes { |
| 43 | /// \brief Contains version information and potentially other metadata, |
| 44 | /// used to determine if we can read this global index file. |
| 45 | METADATA, |
| 46 | /// \brief Describes a module, including its file name and dependencies. |
| 47 | MODULE, |
| 48 | /// \brief The index for identifiers. |
| 49 | IDENTIFIER_INDEX |
| 50 | }; |
| 51 | } |
| 52 | |
| 53 | /// \brief The name of the global index file. |
| 54 | static const char * const IndexFileName = "modules.idx"; |
| 55 | |
| 56 | /// \brief The global index file version. |
| 57 | static const unsigned CurrentVersion = 1; |
| 58 | |
| 59 | //----------------------------------------------------------------------------// |
| 60 | // Global module index writer. |
| 61 | //----------------------------------------------------------------------------// |
| 62 | |
| 63 | namespace { |
| 64 | /// \brief Provides information about a specific module file. |
| 65 | struct ModuleFileInfo { |
| 66 | /// \brief The numberic ID for this module file. |
| 67 | unsigned ID; |
| 68 | |
| 69 | /// \brief The set of modules on which this module depends. Each entry is |
| 70 | /// a module ID. |
| 71 | SmallVector<unsigned, 4> Dependencies; |
| 72 | }; |
| 73 | |
| 74 | /// \brief Builder that generates the global module index file. |
| 75 | class GlobalModuleIndexBuilder { |
| 76 | FileManager &FileMgr; |
| 77 | |
| 78 | /// \brief Mapping from files to module file information. |
| 79 | typedef llvm::MapVector<const FileEntry *, ModuleFileInfo> ModuleFilesMap; |
| 80 | |
| 81 | /// \brief Information about each of the known module files. |
| 82 | ModuleFilesMap ModuleFiles; |
| 83 | |
| 84 | /// \brief Mapping from identifiers to the list of module file IDs that |
| 85 | /// consider this identifier to be interesting. |
| 86 | typedef llvm::StringMap<SmallVector<unsigned, 2> > InterestingIdentifierMap; |
| 87 | |
| 88 | /// \brief A mapping from all interesting identifiers to the set of module |
| 89 | /// files in which those identifiers are considered interesting. |
| 90 | InterestingIdentifierMap InterestingIdentifiers; |
| 91 | |
| 92 | /// \brief Write the block-info block for the global module index file. |
| 93 | void emitBlockInfoBlock(llvm::BitstreamWriter &Stream); |
| 94 | |
| 95 | /// \brief Retrieve the module file information for the given file. |
| 96 | ModuleFileInfo &getModuleFileInfo(const FileEntry *File) { |
| 97 | llvm::MapVector<const FileEntry *, ModuleFileInfo>::iterator Known |
| 98 | = ModuleFiles.find(File); |
| 99 | if (Known != ModuleFiles.end()) |
| 100 | return Known->second; |
| 101 | |
| 102 | unsigned NewID = ModuleFiles.size(); |
| 103 | ModuleFileInfo &Info = ModuleFiles[File]; |
| 104 | Info.ID = NewID; |
| 105 | return Info; |
| 106 | } |
| 107 | |
| 108 | public: |
| 109 | explicit GlobalModuleIndexBuilder(FileManager &FileMgr) : FileMgr(FileMgr){} |
| 110 | |
| 111 | /// \brief Load the contents of the given module file into the builder. |
| 112 | /// |
| 113 | /// \returns true if an error occurred, false otherwise. |
| 114 | bool loadModuleFile(const FileEntry *File); |
| 115 | |
| 116 | /// \brief Write the index to the given bitstream. |
| 117 | void writeIndex(llvm::BitstreamWriter &Stream); |
| 118 | }; |
| 119 | } |
| 120 | |
| 121 | static void emitBlockID(unsigned ID, const char *Name, |
| 122 | llvm::BitstreamWriter &Stream, |
| 123 | SmallVectorImpl<uint64_t> &Record) { |
| 124 | Record.clear(); |
| 125 | Record.push_back(ID); |
| 126 | Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETBID, Record); |
| 127 | |
| 128 | // Emit the block name if present. |
| 129 | if (Name == 0 || Name[0] == 0) return; |
| 130 | Record.clear(); |
| 131 | while (*Name) |
| 132 | Record.push_back(*Name++); |
| 133 | Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_BLOCKNAME, Record); |
| 134 | } |
| 135 | |
| 136 | static void emitRecordID(unsigned ID, const char *Name, |
| 137 | llvm::BitstreamWriter &Stream, |
| 138 | SmallVectorImpl<uint64_t> &Record) { |
| 139 | Record.clear(); |
| 140 | Record.push_back(ID); |
| 141 | while (*Name) |
| 142 | Record.push_back(*Name++); |
| 143 | Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETRECORDNAME, Record); |
| 144 | } |
| 145 | |
| 146 | void |
| 147 | GlobalModuleIndexBuilder::emitBlockInfoBlock(llvm::BitstreamWriter &Stream) { |
| 148 | SmallVector<uint64_t, 64> Record; |
| 149 | Stream.EnterSubblock(llvm::bitc::BLOCKINFO_BLOCK_ID, 3); |
| 150 | |
| 151 | #define BLOCK(X) emitBlockID(X ## _ID, #X, Stream, Record) |
| 152 | #define RECORD(X) emitRecordID(X, #X, Stream, Record) |
| 153 | BLOCK(GLOBAL_INDEX_BLOCK); |
| 154 | RECORD(METADATA); |
| 155 | RECORD(MODULE); |
| 156 | RECORD(IDENTIFIER_INDEX); |
| 157 | #undef RECORD |
| 158 | #undef BLOCK |
| 159 | |
| 160 | Stream.ExitBlock(); |
| 161 | } |
| 162 | |
| 163 | namespace clang { |
| 164 | class InterestingASTIdentifierLookupTrait |
| 165 | : public serialization::reader::ASTIdentifierLookupTraitBase { |
| 166 | |
| 167 | public: |
| 168 | /// \brief The identifier and whether it is "interesting". |
| 169 | typedef std::pair<StringRef, bool> data_type; |
| 170 | |
| 171 | data_type ReadData(const internal_key_type& k, |
| 172 | const unsigned char* d, |
| 173 | unsigned DataLen) { |
| 174 | // The first bit indicates whether this identifier is interesting. |
| 175 | // That's all we care about. |
| 176 | using namespace clang::io; |
| 177 | unsigned RawID = ReadUnalignedLE32(d); |
| 178 | bool IsInteresting = RawID & 0x01; |
| 179 | return std::make_pair(k, IsInteresting); |
| 180 | } |
| 181 | }; |
| 182 | } |
| 183 | |
| 184 | bool GlobalModuleIndexBuilder::loadModuleFile(const FileEntry *File) { |
| 185 | // Open the module file. |
| 186 | OwningPtr<llvm::MemoryBuffer> Buffer; |
| 187 | Buffer.reset(FileMgr.getBufferForFile(File)); |
| 188 | if (!Buffer) { |
| 189 | return true; |
| 190 | } |
| 191 | |
| 192 | // Initialize the input stream |
| 193 | llvm::BitstreamReader InStreamFile; |
| 194 | llvm::BitstreamCursor InStream; |
| 195 | InStreamFile.init((const unsigned char *)Buffer->getBufferStart(), |
| 196 | (const unsigned char *)Buffer->getBufferEnd()); |
| 197 | InStream.init(InStreamFile); |
| 198 | |
| 199 | // Sniff for the signature. |
| 200 | if (InStream.Read(8) != 'C' || |
| 201 | InStream.Read(8) != 'P' || |
| 202 | InStream.Read(8) != 'C' || |
| 203 | InStream.Read(8) != 'H') { |
| 204 | return true; |
| 205 | } |
| 206 | |
| 207 | // Record this module file and assign it a unique ID (if it doesn't have |
| 208 | // one already). |
| 209 | unsigned ID = getModuleFileInfo(File).ID; |
| 210 | |
| 211 | // Search for the blocks and records we care about. |
| 212 | enum { Outer, ControlBlock, ASTBlock } State = Outer; |
| 213 | bool Done = false; |
| 214 | while (!Done) { |
| 215 | const unsigned Flags = llvm::BitstreamCursor::AF_DontPopBlockAtEnd; |
| 216 | llvm::BitstreamEntry Entry = InStream.advance(Flags); |
| 217 | switch (Entry.Kind) { |
| 218 | case llvm::BitstreamEntry::Error: |
| 219 | return true; |
| 220 | |
| 221 | case llvm::BitstreamEntry::Record: |
| 222 | // In the outer state, just skip the record. We don't care. |
| 223 | if (State == Outer) { |
| 224 | InStream.skipRecord(Entry.ID); |
| 225 | continue; |
| 226 | } |
| 227 | |
| 228 | // Handle potentially-interesting records below. |
| 229 | break; |
| 230 | |
| 231 | case llvm::BitstreamEntry::SubBlock: |
| 232 | if (State == Outer && Entry.ID == CONTROL_BLOCK_ID) { |
| 233 | if (InStream.EnterSubBlock(CONTROL_BLOCK_ID)) |
| 234 | return true; |
| 235 | |
| 236 | // Found the control block. |
| 237 | State = ControlBlock; |
| 238 | continue; |
| 239 | } |
| 240 | |
| 241 | if (State == Outer && Entry.ID == AST_BLOCK_ID) { |
| 242 | if (InStream.EnterSubBlock(AST_BLOCK_ID)) |
| 243 | return true; |
| 244 | |
| 245 | // Found the AST block. |
| 246 | State = ASTBlock; |
| 247 | continue; |
| 248 | |
| 249 | } |
| 250 | |
| 251 | if (InStream.SkipBlock()) |
| 252 | return true; |
| 253 | |
| 254 | continue; |
| 255 | |
| 256 | case llvm::BitstreamEntry::EndBlock: |
| 257 | if (State == Outer) { |
| 258 | Done = true; |
| 259 | } |
| 260 | State = Outer; |
| 261 | continue; |
| 262 | } |
| 263 | |
| 264 | // Read the given record. |
| 265 | SmallVector<uint64_t, 64> Record; |
| 266 | StringRef Blob; |
| 267 | unsigned Code = InStream.readRecord(Entry.ID, Record, &Blob); |
| 268 | |
| 269 | // Handle module dependencies. |
| 270 | if (State == ControlBlock && Code == IMPORTS) { |
| 271 | // Load each of the imported PCH files. |
| 272 | unsigned Idx = 0, N = Record.size(); |
| 273 | while (Idx < N) { |
| 274 | // Read information about the AST file. |
| 275 | |
| 276 | // Skip the imported kind |
| 277 | ++Idx; |
| 278 | |
| 279 | // Skip the import location |
| 280 | ++Idx; |
| 281 | |
| 282 | // Retrieve the imported file name. |
| 283 | unsigned Length = Record[Idx++]; |
| 284 | SmallString<128> ImportedFile(Record.begin() + Idx, |
| 285 | Record.begin() + Idx + Length); |
| 286 | Idx += Length; |
| 287 | |
| 288 | // Find the imported module file. |
| 289 | const FileEntry *DependsOnFile = FileMgr.getFile(ImportedFile); |
| 290 | if (!DependsOnFile) |
| 291 | return true; |
| 292 | |
| 293 | // Record the dependency. |
| 294 | unsigned DependsOnID = getModuleFileInfo(DependsOnFile).ID; |
| 295 | getModuleFileInfo(File).Dependencies.push_back(DependsOnID); |
| 296 | } |
| 297 | |
| 298 | continue; |
| 299 | } |
| 300 | |
| 301 | // Handle the identifier table |
| 302 | if (State == ASTBlock && Code == IDENTIFIER_TABLE && Record[0] > 0) { |
| 303 | typedef OnDiskChainedHashTable<InterestingASTIdentifierLookupTrait> |
| 304 | InterestingIdentifierTable; |
| 305 | llvm::OwningPtr<InterestingIdentifierTable> |
| 306 | Table(InterestingIdentifierTable::Create( |
| 307 | (const unsigned char *)Blob.data() + Record[0], |
| 308 | (const unsigned char *)Blob.data())); |
| 309 | for (InterestingIdentifierTable::data_iterator D = Table->data_begin(), |
| 310 | DEnd = Table->data_end(); |
| 311 | D != DEnd; ++D) { |
| 312 | std::pair<StringRef, bool> Ident = *D; |
| 313 | if (Ident.second) |
| 314 | InterestingIdentifiers[Ident.first].push_back(ID); |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | // FIXME: Handle the selector table. |
| 319 | |
| 320 | // We don't care about this record. |
| 321 | } |
| 322 | |
| 323 | return false; |
| 324 | } |
| 325 | |
| 326 | namespace { |
| 327 | |
| 328 | /// \brief Trait used to generate the identifier index as an on-disk hash |
| 329 | /// table. |
| 330 | class IdentifierIndexWriterTrait { |
| 331 | public: |
| 332 | typedef StringRef key_type; |
| 333 | typedef StringRef key_type_ref; |
| 334 | typedef SmallVector<unsigned, 2> data_type; |
| 335 | typedef const SmallVector<unsigned, 2> &data_type_ref; |
| 336 | |
| 337 | static unsigned ComputeHash(key_type_ref Key) { |
| 338 | return llvm::HashString(Key); |
| 339 | } |
| 340 | |
| 341 | std::pair<unsigned,unsigned> |
| 342 | EmitKeyDataLength(raw_ostream& Out, key_type_ref Key, data_type_ref Data) { |
| 343 | unsigned KeyLen = Key.size(); |
| 344 | unsigned DataLen = Data.size() * 4; |
| 345 | clang::io::Emit16(Out, KeyLen); |
| 346 | clang::io::Emit16(Out, DataLen); |
| 347 | return std::make_pair(KeyLen, DataLen); |
| 348 | } |
| 349 | |
| 350 | void EmitKey(raw_ostream& Out, key_type_ref Key, unsigned KeyLen) { |
| 351 | Out.write(Key.data(), KeyLen); |
| 352 | } |
| 353 | |
| 354 | void EmitData(raw_ostream& Out, key_type_ref Key, data_type_ref Data, |
| 355 | unsigned DataLen) { |
| 356 | for (unsigned I = 0, N = Data.size(); I != N; ++I) |
| 357 | clang::io::Emit32(Out, Data[I]); |
| 358 | } |
| 359 | }; |
| 360 | |
| 361 | } |
| 362 | |
| 363 | void GlobalModuleIndexBuilder::writeIndex(llvm::BitstreamWriter &Stream) { |
| 364 | using namespace llvm; |
| 365 | |
| 366 | // Emit the file header. |
| 367 | Stream.Emit((unsigned)'B', 8); |
| 368 | Stream.Emit((unsigned)'C', 8); |
| 369 | Stream.Emit((unsigned)'G', 8); |
| 370 | Stream.Emit((unsigned)'I', 8); |
| 371 | |
| 372 | // Write the block-info block, which describes the records in this bitcode |
| 373 | // file. |
| 374 | emitBlockInfoBlock(Stream); |
| 375 | |
| 376 | Stream.EnterSubblock(GLOBAL_INDEX_BLOCK_ID, 3); |
| 377 | |
| 378 | // Write the metadata. |
| 379 | SmallVector<uint64_t, 2> Record; |
| 380 | Record.push_back(CurrentVersion); |
| 381 | Stream.EmitRecord(METADATA, Record); |
| 382 | |
| 383 | // Write the set of known module files. |
| 384 | for (ModuleFilesMap::iterator M = ModuleFiles.begin(), |
| 385 | MEnd = ModuleFiles.end(); |
| 386 | M != MEnd; ++M) { |
| 387 | Record.clear(); |
| 388 | Record.push_back(M->second.ID); |
| 389 | Record.push_back(M->first->getSize()); |
| 390 | Record.push_back(M->first->getModificationTime()); |
| 391 | |
| 392 | // File name |
| 393 | StringRef Name(M->first->getName()); |
| 394 | Record.push_back(Name.size()); |
| 395 | Record.append(Name.begin(), Name.end()); |
| 396 | |
| 397 | // Dependencies |
| 398 | Record.push_back(M->second.Dependencies.size()); |
| 399 | Record.append(M->second.Dependencies.begin(), M->second.Dependencies.end()); |
| 400 | Stream.EmitRecord(MODULE, Record); |
| 401 | } |
| 402 | |
| 403 | // Write the identifier -> module file mapping. |
| 404 | { |
| 405 | OnDiskChainedHashTableGenerator<IdentifierIndexWriterTrait> Generator; |
| 406 | IdentifierIndexWriterTrait Trait; |
| 407 | |
| 408 | // Populate the hash table. |
| 409 | for (InterestingIdentifierMap::iterator I = InterestingIdentifiers.begin(), |
| 410 | IEnd = InterestingIdentifiers.end(); |
| 411 | I != IEnd; ++I) { |
| 412 | Generator.insert(I->first(), I->second, Trait); |
| 413 | } |
| 414 | |
| 415 | // Create the on-disk hash table in a buffer. |
| 416 | SmallString<4096> IdentifierTable; |
| 417 | uint32_t BucketOffset; |
| 418 | { |
| 419 | llvm::raw_svector_ostream Out(IdentifierTable); |
| 420 | // Make sure that no bucket is at offset 0 |
| 421 | clang::io::Emit32(Out, 0); |
| 422 | BucketOffset = Generator.Emit(Out, Trait); |
| 423 | } |
| 424 | |
| 425 | // Create a blob abbreviation |
| 426 | BitCodeAbbrev *Abbrev = new BitCodeAbbrev(); |
| 427 | Abbrev->Add(BitCodeAbbrevOp(IDENTIFIER_INDEX)); |
| 428 | Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32)); |
| 429 | Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); |
| 430 | unsigned IDTableAbbrev = Stream.EmitAbbrev(Abbrev); |
| 431 | |
| 432 | // Write the identifier table |
| 433 | Record.clear(); |
| 434 | Record.push_back(IDENTIFIER_INDEX); |
| 435 | Record.push_back(BucketOffset); |
| 436 | Stream.EmitRecordWithBlob(IDTableAbbrev, Record, IdentifierTable.str()); |
| 437 | } |
| 438 | |
| 439 | // FIXME: Selectors. |
| 440 | |
| 441 | Stream.ExitBlock(); |
| 442 | } |
| 443 | |
| 444 | GlobalModuleIndex::ErrorCode |
| 445 | GlobalModuleIndex::writeIndex(FileManager &FileMgr, StringRef Path) { |
| 446 | llvm::SmallString<128> IndexPath; |
| 447 | IndexPath += Path; |
| 448 | llvm::sys::path::append(IndexPath, IndexFileName); |
| 449 | |
| 450 | // Coordinate building the global index file with other processes that might |
| 451 | // try to do the same. |
| 452 | llvm::LockFileManager Locked(IndexPath); |
| 453 | switch (Locked) { |
| 454 | case llvm::LockFileManager::LFS_Error: |
| 455 | return EC_IOError; |
| 456 | |
| 457 | case llvm::LockFileManager::LFS_Owned: |
| 458 | // We're responsible for building the index ourselves. Do so below. |
| 459 | break; |
| 460 | |
| 461 | case llvm::LockFileManager::LFS_Shared: |
| 462 | // Someone else is responsible for building the index. We don't care |
| 463 | // when they finish, so we're done. |
| 464 | return EC_Building; |
| 465 | } |
| 466 | |
| 467 | // The module index builder. |
| 468 | GlobalModuleIndexBuilder Builder(FileMgr); |
| 469 | |
| 470 | // Load each of the module files. |
| 471 | llvm::error_code EC; |
| 472 | for (llvm::sys::fs::directory_iterator D(Path, EC), DEnd; |
| 473 | D != DEnd && !EC; |
| 474 | D.increment(EC)) { |
| 475 | // If this isn't a module file, we don't care. |
| 476 | if (llvm::sys::path::extension(D->path()) != ".pcm") { |
| 477 | // ... unless it's a .pcm.lock file, which indicates that someone is |
| 478 | // in the process of rebuilding a module. They'll rebuild the index |
| 479 | // at the end of that translation unit, so we don't have to. |
| 480 | if (llvm::sys::path::extension(D->path()) == ".pcm.lock") |
| 481 | return EC_Building; |
| 482 | |
| 483 | continue; |
| 484 | } |
| 485 | |
| 486 | // If we can't find the module file, skip it. |
| 487 | const FileEntry *ModuleFile = FileMgr.getFile(D->path()); |
| 488 | if (!ModuleFile) |
| 489 | continue; |
| 490 | |
| 491 | // Load this module file. |
| 492 | if (Builder.loadModuleFile(ModuleFile)) |
| 493 | return EC_IOError; |
| 494 | } |
| 495 | |
| 496 | // The output buffer, into which the global index will be written. |
| 497 | SmallVector<char, 16> OutputBuffer; |
| 498 | { |
| 499 | llvm::BitstreamWriter OutputStream(OutputBuffer); |
| 500 | Builder.writeIndex(OutputStream); |
| 501 | } |
| 502 | |
| 503 | // Write the global index file to a temporary file. |
| 504 | llvm::SmallString<128> IndexTmpPath; |
| 505 | int TmpFD; |
| 506 | if (llvm::sys::fs::unique_file(IndexPath + "-%%%%%%%%", TmpFD, IndexTmpPath)) |
| 507 | return EC_IOError; |
| 508 | |
| 509 | // Open the temporary global index file for output. |
NAKAMURA Takumi | d2db16f | 2013-01-24 08:20:11 +0000 | [diff] [blame^] | 510 | llvm::raw_fd_ostream Out(TmpFD, true); |
Douglas Gregor | a6b00fc | 2013-01-23 22:38:11 +0000 | [diff] [blame] | 511 | if (Out.has_error()) |
| 512 | return EC_IOError; |
| 513 | |
| 514 | // Write the index. |
| 515 | Out.write(OutputBuffer.data(), OutputBuffer.size()); |
| 516 | Out.close(); |
| 517 | if (Out.has_error()) |
| 518 | return EC_IOError; |
| 519 | |
| 520 | // Remove the old index file. It isn't relevant any more. |
| 521 | bool OldIndexExisted; |
| 522 | llvm::sys::fs::remove(IndexPath.str(), OldIndexExisted); |
| 523 | |
| 524 | // Rename the newly-written index file to the proper name. |
| 525 | if (llvm::sys::fs::rename(IndexTmpPath.str(), IndexPath.str())) { |
| 526 | // Rename failed; just remove the |
| 527 | llvm::sys::fs::remove(IndexTmpPath.str(), OldIndexExisted); |
| 528 | return EC_IOError; |
| 529 | } |
| 530 | |
| 531 | // We're done. |
| 532 | return EC_None; |
| 533 | } |