1 //===--- GlobalModuleIndex.cpp - Global Module Index ------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the GlobalModuleIndex class.
12 //===----------------------------------------------------------------------===//
14 #include "ASTReaderInternals.h"
15 #include "clang/Basic/FileManager.h"
16 #include "clang/Lex/HeaderSearch.h"
17 #include "clang/Serialization/ASTBitCodes.h"
18 #include "clang/Serialization/GlobalModuleIndex.h"
19 #include "clang/Serialization/Module.h"
20 #include "llvm/ADT/DenseMap.h"
21 #include "llvm/ADT/MapVector.h"
22 #include "llvm/ADT/SmallString.h"
23 #include "llvm/ADT/StringExtras.h"
24 #include "llvm/Bitcode/BitstreamReader.h"
25 #include "llvm/Bitcode/BitstreamWriter.h"
26 #include "llvm/Support/FileSystem.h"
27 #include "llvm/Support/LockFileManager.h"
28 #include "llvm/Support/MemoryBuffer.h"
29 #include "llvm/Support/OnDiskHashTable.h"
30 #include "llvm/Support/Path.h"
32 using namespace clang;
33 using namespace serialization;
35 //----------------------------------------------------------------------------//
37 //----------------------------------------------------------------------------//
40 /// \brief The block containing the index.
41 GLOBAL_INDEX_BLOCK_ID = llvm::bitc::FIRST_APPLICATION_BLOCKID
44 /// \brief Describes the record types in the index.
45 enum IndexRecordTypes {
46 /// \brief Contains version information and potentially other metadata,
47 /// used to determine if we can read this global index file.
49 /// \brief Describes a module, including its file name and dependencies.
51 /// \brief The index for identifiers.
56 /// \brief The name of the global index file.
57 static const char * const IndexFileName = "modules.idx";
59 /// \brief The global index file version.
60 static const unsigned CurrentVersion = 1;
62 //----------------------------------------------------------------------------//
63 // Global module index reader.
64 //----------------------------------------------------------------------------//
68 /// \brief Trait used to read the identifier index from the on-disk hash
70 class IdentifierIndexReaderTrait {
72 typedef StringRef external_key_type;
73 typedef StringRef internal_key_type;
74 typedef SmallVector<unsigned, 2> data_type;
75 typedef unsigned hash_value_type;
76 typedef unsigned offset_type;
78 static bool EqualKey(const internal_key_type& a, const internal_key_type& b) {
82 static hash_value_type ComputeHash(const internal_key_type& a) {
83 return llvm::HashString(a);
86 static std::pair<unsigned, unsigned>
87 ReadKeyDataLength(const unsigned char*& d) {
88 using namespace llvm::support;
89 unsigned KeyLen = endian::readNext<uint16_t, little, unaligned>(d);
90 unsigned DataLen = endian::readNext<uint16_t, little, unaligned>(d);
91 return std::make_pair(KeyLen, DataLen);
94 static const internal_key_type&
95 GetInternalKey(const external_key_type& x) { return x; }
97 static const external_key_type&
98 GetExternalKey(const internal_key_type& x) { return x; }
100 static internal_key_type ReadKey(const unsigned char* d, unsigned n) {
101 return StringRef((const char *)d, n);
104 static data_type ReadData(const internal_key_type& k,
105 const unsigned char* d,
107 using namespace llvm::support;
110 while (DataLen > 0) {
111 unsigned ID = endian::readNext<uint32_t, little, unaligned>(d);
112 Result.push_back(ID);
120 typedef llvm::OnDiskIterableChainedHashTable<IdentifierIndexReaderTrait>
121 IdentifierIndexTable;
125 GlobalModuleIndex::GlobalModuleIndex(std::unique_ptr<llvm::MemoryBuffer> Buffer,
126 llvm::BitstreamCursor Cursor)
127 : Buffer(std::move(Buffer)), IdentifierIndex(), NumIdentifierLookups(),
128 NumIdentifierLookupHits() {
129 // Read the global index.
130 bool InGlobalIndexBlock = false;
133 llvm::BitstreamEntry Entry = Cursor.advance();
135 switch (Entry.Kind) {
136 case llvm::BitstreamEntry::Error:
139 case llvm::BitstreamEntry::EndBlock:
140 if (InGlobalIndexBlock) {
141 InGlobalIndexBlock = false;
148 case llvm::BitstreamEntry::Record:
149 // Entries in the global index block are handled below.
150 if (InGlobalIndexBlock)
155 case llvm::BitstreamEntry::SubBlock:
156 if (!InGlobalIndexBlock && Entry.ID == GLOBAL_INDEX_BLOCK_ID) {
157 if (Cursor.EnterSubBlock(GLOBAL_INDEX_BLOCK_ID))
160 InGlobalIndexBlock = true;
161 } else if (Cursor.SkipBlock()) {
167 SmallVector<uint64_t, 64> Record;
169 switch ((IndexRecordTypes)Cursor.readRecord(Entry.ID, Record, &Blob)) {
171 // Make sure that the version matches.
172 if (Record.size() < 1 || Record[0] != CurrentVersion)
178 unsigned ID = Record[Idx++];
180 // Make room for this module's information.
181 if (ID == Modules.size())
182 Modules.push_back(ModuleInfo());
184 Modules.resize(ID + 1);
186 // Size/modification time for this module file at the time the
187 // global index was built.
188 Modules[ID].Size = Record[Idx++];
189 Modules[ID].ModTime = Record[Idx++];
192 unsigned NameLen = Record[Idx++];
193 Modules[ID].FileName.assign(Record.begin() + Idx,
194 Record.begin() + Idx + NameLen);
198 unsigned NumDeps = Record[Idx++];
199 Modules[ID].Dependencies.insert(Modules[ID].Dependencies.end(),
200 Record.begin() + Idx,
201 Record.begin() + Idx + NumDeps);
204 // Make sure we're at the end of the record.
205 assert(Idx == Record.size() && "More module info?");
207 // Record this module as an unresolved module.
208 // FIXME: this doesn't work correctly for module names containing path
210 StringRef ModuleName = llvm::sys::path::stem(Modules[ID].FileName);
211 // Remove the -<hash of ModuleMapPath>
212 ModuleName = ModuleName.rsplit('-').first;
213 UnresolvedModules[ModuleName] = ID;
217 case IDENTIFIER_INDEX:
218 // Wire up the identifier index.
220 IdentifierIndex = IdentifierIndexTable::Create(
221 (const unsigned char *)Blob.data() + Record[0],
222 (const unsigned char *)Blob.data() + sizeof(uint32_t),
223 (const unsigned char *)Blob.data(), IdentifierIndexReaderTrait());
230 GlobalModuleIndex::~GlobalModuleIndex() {
231 delete static_cast<IdentifierIndexTable *>(IdentifierIndex);
234 std::pair<GlobalModuleIndex *, GlobalModuleIndex::ErrorCode>
235 GlobalModuleIndex::readIndex(StringRef Path) {
236 // Load the index file, if it's there.
237 llvm::SmallString<128> IndexPath;
239 llvm::sys::path::append(IndexPath, IndexFileName);
241 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> BufferOrErr =
242 llvm::MemoryBuffer::getFile(IndexPath.c_str());
244 return std::make_pair(nullptr, EC_NotFound);
245 std::unique_ptr<llvm::MemoryBuffer> Buffer = std::move(BufferOrErr.get());
247 /// \brief The bitstream reader from which we'll read the AST file.
248 llvm::BitstreamReader Reader((const unsigned char *)Buffer->getBufferStart(),
249 (const unsigned char *)Buffer->getBufferEnd());
251 /// \brief The main bitstream cursor for the main block.
252 llvm::BitstreamCursor Cursor(Reader);
254 // Sniff for the signature.
255 if (Cursor.Read(8) != 'B' ||
256 Cursor.Read(8) != 'C' ||
257 Cursor.Read(8) != 'G' ||
258 Cursor.Read(8) != 'I') {
259 return std::make_pair(nullptr, EC_IOError);
262 return std::make_pair(new GlobalModuleIndex(std::move(Buffer), Cursor),
267 GlobalModuleIndex::getKnownModules(SmallVectorImpl<ModuleFile *> &ModuleFiles) {
269 for (unsigned I = 0, N = Modules.size(); I != N; ++I) {
270 if (ModuleFile *MF = Modules[I].File)
271 ModuleFiles.push_back(MF);
275 void GlobalModuleIndex::getModuleDependencies(
277 SmallVectorImpl<ModuleFile *> &Dependencies) {
278 // Look for information about this module file.
279 llvm::DenseMap<ModuleFile *, unsigned>::iterator Known
280 = ModulesByFile.find(File);
281 if (Known == ModulesByFile.end())
284 // Record dependencies.
285 Dependencies.clear();
286 ArrayRef<unsigned> StoredDependencies = Modules[Known->second].Dependencies;
287 for (unsigned I = 0, N = StoredDependencies.size(); I != N; ++I) {
288 if (ModuleFile *MF = Modules[I].File)
289 Dependencies.push_back(MF);
293 bool GlobalModuleIndex::lookupIdentifier(StringRef Name, HitSet &Hits) {
296 // If there's no identifier index, there is nothing we can do.
297 if (!IdentifierIndex)
300 // Look into the identifier index.
301 ++NumIdentifierLookups;
302 IdentifierIndexTable &Table
303 = *static_cast<IdentifierIndexTable *>(IdentifierIndex);
304 IdentifierIndexTable::iterator Known = Table.find(Name);
305 if (Known == Table.end()) {
309 SmallVector<unsigned, 2> ModuleIDs = *Known;
310 for (unsigned I = 0, N = ModuleIDs.size(); I != N; ++I) {
311 if (ModuleFile *MF = Modules[ModuleIDs[I]].File)
315 ++NumIdentifierLookupHits;
319 bool GlobalModuleIndex::loadedModuleFile(ModuleFile *File) {
320 // Look for the module in the global module index based on the module name.
321 StringRef Name = File->ModuleName;
322 llvm::StringMap<unsigned>::iterator Known = UnresolvedModules.find(Name);
323 if (Known == UnresolvedModules.end()) {
327 // Rectify this module with the global module index.
328 ModuleInfo &Info = Modules[Known->second];
330 // If the size and modification time match what we expected, record this
333 if (File->File->getSize() == Info.Size &&
334 File->File->getModificationTime() == Info.ModTime) {
336 ModulesByFile[File] = Known->second;
341 // One way or another, we have resolved this module file.
342 UnresolvedModules.erase(Known);
346 void GlobalModuleIndex::printStats() {
347 std::fprintf(stderr, "*** Global Module Index Statistics:\n");
348 if (NumIdentifierLookups) {
349 fprintf(stderr, " %u / %u identifier lookups succeeded (%f%%)\n",
350 NumIdentifierLookupHits, NumIdentifierLookups,
351 (double)NumIdentifierLookupHits*100.0/NumIdentifierLookups);
353 std::fprintf(stderr, "\n");
356 void GlobalModuleIndex::dump() {
357 llvm::errs() << "*** Global Module Index Dump:\n";
358 llvm::errs() << "Module files:\n";
359 for (auto &MI : Modules) {
360 llvm::errs() << "** " << MI.FileName << "\n";
364 llvm::errs() << "\n";
366 llvm::errs() << "\n";
369 //----------------------------------------------------------------------------//
370 // Global module index writer.
371 //----------------------------------------------------------------------------//
374 /// \brief Provides information about a specific module file.
375 struct ModuleFileInfo {
376 /// \brief The numberic ID for this module file.
379 /// \brief The set of modules on which this module depends. Each entry is
381 SmallVector<unsigned, 4> Dependencies;
384 /// \brief Builder that generates the global module index file.
385 class GlobalModuleIndexBuilder {
386 FileManager &FileMgr;
388 /// \brief Mapping from files to module file information.
389 typedef llvm::MapVector<const FileEntry *, ModuleFileInfo> ModuleFilesMap;
391 /// \brief Information about each of the known module files.
392 ModuleFilesMap ModuleFiles;
394 /// \brief Mapping from identifiers to the list of module file IDs that
395 /// consider this identifier to be interesting.
396 typedef llvm::StringMap<SmallVector<unsigned, 2> > InterestingIdentifierMap;
398 /// \brief A mapping from all interesting identifiers to the set of module
399 /// files in which those identifiers are considered interesting.
400 InterestingIdentifierMap InterestingIdentifiers;
402 /// \brief Write the block-info block for the global module index file.
403 void emitBlockInfoBlock(llvm::BitstreamWriter &Stream);
405 /// \brief Retrieve the module file information for the given file.
406 ModuleFileInfo &getModuleFileInfo(const FileEntry *File) {
407 llvm::MapVector<const FileEntry *, ModuleFileInfo>::iterator Known
408 = ModuleFiles.find(File);
409 if (Known != ModuleFiles.end())
410 return Known->second;
412 unsigned NewID = ModuleFiles.size();
413 ModuleFileInfo &Info = ModuleFiles[File];
419 explicit GlobalModuleIndexBuilder(FileManager &FileMgr) : FileMgr(FileMgr){}
421 /// \brief Load the contents of the given module file into the builder.
423 /// \returns true if an error occurred, false otherwise.
424 bool loadModuleFile(const FileEntry *File);
426 /// \brief Write the index to the given bitstream.
427 void writeIndex(llvm::BitstreamWriter &Stream);
431 static void emitBlockID(unsigned ID, const char *Name,
432 llvm::BitstreamWriter &Stream,
433 SmallVectorImpl<uint64_t> &Record) {
435 Record.push_back(ID);
436 Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETBID, Record);
438 // Emit the block name if present.
439 if (!Name || Name[0] == 0) return;
442 Record.push_back(*Name++);
443 Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_BLOCKNAME, Record);
446 static void emitRecordID(unsigned ID, const char *Name,
447 llvm::BitstreamWriter &Stream,
448 SmallVectorImpl<uint64_t> &Record) {
450 Record.push_back(ID);
452 Record.push_back(*Name++);
453 Stream.EmitRecord(llvm::bitc::BLOCKINFO_CODE_SETRECORDNAME, Record);
457 GlobalModuleIndexBuilder::emitBlockInfoBlock(llvm::BitstreamWriter &Stream) {
458 SmallVector<uint64_t, 64> Record;
459 Stream.EnterSubblock(llvm::bitc::BLOCKINFO_BLOCK_ID, 3);
461 #define BLOCK(X) emitBlockID(X ## _ID, #X, Stream, Record)
462 #define RECORD(X) emitRecordID(X, #X, Stream, Record)
463 BLOCK(GLOBAL_INDEX_BLOCK);
464 RECORD(INDEX_METADATA);
466 RECORD(IDENTIFIER_INDEX);
474 class InterestingASTIdentifierLookupTrait
475 : public serialization::reader::ASTIdentifierLookupTraitBase {
478 /// \brief The identifier and whether it is "interesting".
479 typedef std::pair<StringRef, bool> data_type;
481 data_type ReadData(const internal_key_type& k,
482 const unsigned char* d,
484 // The first bit indicates whether this identifier is interesting.
485 // That's all we care about.
486 using namespace llvm::support;
487 unsigned RawID = endian::readNext<uint32_t, little, unaligned>(d);
488 bool IsInteresting = RawID & 0x01;
489 return std::make_pair(k, IsInteresting);
494 bool GlobalModuleIndexBuilder::loadModuleFile(const FileEntry *File) {
495 // Open the module file.
497 auto Buffer = FileMgr.getBufferForFile(File, /*isVolatile=*/true);
502 // Initialize the input stream
503 llvm::BitstreamReader InStreamFile;
504 InStreamFile.init((const unsigned char *)(*Buffer)->getBufferStart(),
505 (const unsigned char *)(*Buffer)->getBufferEnd());
506 llvm::BitstreamCursor InStream(InStreamFile);
508 // Sniff for the signature.
509 if (InStream.Read(8) != 'C' ||
510 InStream.Read(8) != 'P' ||
511 InStream.Read(8) != 'C' ||
512 InStream.Read(8) != 'H') {
516 // Record this module file and assign it a unique ID (if it doesn't have
518 unsigned ID = getModuleFileInfo(File).ID;
520 // Search for the blocks and records we care about.
521 enum { Other, ControlBlock, ASTBlock } State = Other;
524 llvm::BitstreamEntry Entry = InStream.advance();
525 switch (Entry.Kind) {
526 case llvm::BitstreamEntry::Error:
530 case llvm::BitstreamEntry::Record:
531 // In the 'other' state, just skip the record. We don't care.
532 if (State == Other) {
533 InStream.skipRecord(Entry.ID);
537 // Handle potentially-interesting records below.
540 case llvm::BitstreamEntry::SubBlock:
541 if (Entry.ID == CONTROL_BLOCK_ID) {
542 if (InStream.EnterSubBlock(CONTROL_BLOCK_ID))
545 // Found the control block.
546 State = ControlBlock;
550 if (Entry.ID == AST_BLOCK_ID) {
551 if (InStream.EnterSubBlock(AST_BLOCK_ID))
554 // Found the AST block.
559 if (InStream.SkipBlock())
564 case llvm::BitstreamEntry::EndBlock:
569 // Read the given record.
570 SmallVector<uint64_t, 64> Record;
572 unsigned Code = InStream.readRecord(Entry.ID, Record, &Blob);
574 // Handle module dependencies.
575 if (State == ControlBlock && Code == IMPORTS) {
576 // Load each of the imported PCH files.
577 unsigned Idx = 0, N = Record.size();
579 // Read information about the AST file.
581 // Skip the imported kind
584 // Skip the import location
587 // Load stored size/modification time.
588 off_t StoredSize = (off_t)Record[Idx++];
589 time_t StoredModTime = (time_t)Record[Idx++];
591 // Skip the stored signature.
592 // FIXME: we could read the signature out of the import and validate it.
595 // Retrieve the imported file name.
596 unsigned Length = Record[Idx++];
597 SmallString<128> ImportedFile(Record.begin() + Idx,
598 Record.begin() + Idx + Length);
601 // Find the imported module file.
602 const FileEntry *DependsOnFile
603 = FileMgr.getFile(ImportedFile, /*openFile=*/false,
604 /*cacheFailure=*/false);
605 if (!DependsOnFile ||
606 (StoredSize != DependsOnFile->getSize()) ||
607 (StoredModTime != DependsOnFile->getModificationTime()))
610 // Record the dependency.
611 unsigned DependsOnID = getModuleFileInfo(DependsOnFile).ID;
612 getModuleFileInfo(File).Dependencies.push_back(DependsOnID);
618 // Handle the identifier table
619 if (State == ASTBlock && Code == IDENTIFIER_TABLE && Record[0] > 0) {
620 typedef llvm::OnDiskIterableChainedHashTable<
621 InterestingASTIdentifierLookupTrait> InterestingIdentifierTable;
622 std::unique_ptr<InterestingIdentifierTable> Table(
623 InterestingIdentifierTable::Create(
624 (const unsigned char *)Blob.data() + Record[0],
625 (const unsigned char *)Blob.data() + sizeof(uint32_t),
626 (const unsigned char *)Blob.data()));
627 for (InterestingIdentifierTable::data_iterator D = Table->data_begin(),
628 DEnd = Table->data_end();
630 std::pair<StringRef, bool> Ident = *D;
632 InterestingIdentifiers[Ident.first].push_back(ID);
634 (void)InterestingIdentifiers[Ident.first];
638 // We don't care about this record.
646 /// \brief Trait used to generate the identifier index as an on-disk hash
648 class IdentifierIndexWriterTrait {
650 typedef StringRef key_type;
651 typedef StringRef key_type_ref;
652 typedef SmallVector<unsigned, 2> data_type;
653 typedef const SmallVector<unsigned, 2> &data_type_ref;
654 typedef unsigned hash_value_type;
655 typedef unsigned offset_type;
657 static hash_value_type ComputeHash(key_type_ref Key) {
658 return llvm::HashString(Key);
661 std::pair<unsigned,unsigned>
662 EmitKeyDataLength(raw_ostream& Out, key_type_ref Key, data_type_ref Data) {
663 using namespace llvm::support;
664 endian::Writer<little> LE(Out);
665 unsigned KeyLen = Key.size();
666 unsigned DataLen = Data.size() * 4;
667 LE.write<uint16_t>(KeyLen);
668 LE.write<uint16_t>(DataLen);
669 return std::make_pair(KeyLen, DataLen);
672 void EmitKey(raw_ostream& Out, key_type_ref Key, unsigned KeyLen) {
673 Out.write(Key.data(), KeyLen);
676 void EmitData(raw_ostream& Out, key_type_ref Key, data_type_ref Data,
678 using namespace llvm::support;
679 for (unsigned I = 0, N = Data.size(); I != N; ++I)
680 endian::Writer<little>(Out).write<uint32_t>(Data[I]);
686 void GlobalModuleIndexBuilder::writeIndex(llvm::BitstreamWriter &Stream) {
687 using namespace llvm;
689 // Emit the file header.
690 Stream.Emit((unsigned)'B', 8);
691 Stream.Emit((unsigned)'C', 8);
692 Stream.Emit((unsigned)'G', 8);
693 Stream.Emit((unsigned)'I', 8);
695 // Write the block-info block, which describes the records in this bitcode
697 emitBlockInfoBlock(Stream);
699 Stream.EnterSubblock(GLOBAL_INDEX_BLOCK_ID, 3);
701 // Write the metadata.
702 SmallVector<uint64_t, 2> Record;
703 Record.push_back(CurrentVersion);
704 Stream.EmitRecord(INDEX_METADATA, Record);
706 // Write the set of known module files.
707 for (ModuleFilesMap::iterator M = ModuleFiles.begin(),
708 MEnd = ModuleFiles.end();
711 Record.push_back(M->second.ID);
712 Record.push_back(M->first->getSize());
713 Record.push_back(M->first->getModificationTime());
716 StringRef Name(M->first->getName());
717 Record.push_back(Name.size());
718 Record.append(Name.begin(), Name.end());
721 Record.push_back(M->second.Dependencies.size());
722 Record.append(M->second.Dependencies.begin(), M->second.Dependencies.end());
723 Stream.EmitRecord(MODULE, Record);
726 // Write the identifier -> module file mapping.
728 llvm::OnDiskChainedHashTableGenerator<IdentifierIndexWriterTrait> Generator;
729 IdentifierIndexWriterTrait Trait;
731 // Populate the hash table.
732 for (InterestingIdentifierMap::iterator I = InterestingIdentifiers.begin(),
733 IEnd = InterestingIdentifiers.end();
735 Generator.insert(I->first(), I->second, Trait);
738 // Create the on-disk hash table in a buffer.
739 SmallString<4096> IdentifierTable;
740 uint32_t BucketOffset;
742 using namespace llvm::support;
743 llvm::raw_svector_ostream Out(IdentifierTable);
744 // Make sure that no bucket is at offset 0
745 endian::Writer<little>(Out).write<uint32_t>(0);
746 BucketOffset = Generator.Emit(Out, Trait);
749 // Create a blob abbreviation
750 BitCodeAbbrev *Abbrev = new BitCodeAbbrev();
751 Abbrev->Add(BitCodeAbbrevOp(IDENTIFIER_INDEX));
752 Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 32));
753 Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
754 unsigned IDTableAbbrev = Stream.EmitAbbrev(Abbrev);
756 // Write the identifier table
758 Record.push_back(IDENTIFIER_INDEX);
759 Record.push_back(BucketOffset);
760 Stream.EmitRecordWithBlob(IDTableAbbrev, Record, IdentifierTable.str());
766 GlobalModuleIndex::ErrorCode
767 GlobalModuleIndex::writeIndex(FileManager &FileMgr, StringRef Path) {
768 llvm::SmallString<128> IndexPath;
770 llvm::sys::path::append(IndexPath, IndexFileName);
772 // Coordinate building the global index file with other processes that might
773 // try to do the same.
774 llvm::LockFileManager Locked(IndexPath);
776 case llvm::LockFileManager::LFS_Error:
779 case llvm::LockFileManager::LFS_Owned:
780 // We're responsible for building the index ourselves. Do so below.
783 case llvm::LockFileManager::LFS_Shared:
784 // Someone else is responsible for building the index. We don't care
785 // when they finish, so we're done.
789 // The module index builder.
790 GlobalModuleIndexBuilder Builder(FileMgr);
792 // Load each of the module files.
794 for (llvm::sys::fs::directory_iterator D(Path, EC), DEnd;
797 // If this isn't a module file, we don't care.
798 if (llvm::sys::path::extension(D->path()) != ".pcm") {
799 // ... unless it's a .pcm.lock file, which indicates that someone is
800 // in the process of rebuilding a module. They'll rebuild the index
801 // at the end of that translation unit, so we don't have to.
802 if (llvm::sys::path::extension(D->path()) == ".pcm.lock")
808 // If we can't find the module file, skip it.
809 const FileEntry *ModuleFile = FileMgr.getFile(D->path());
813 // Load this module file.
814 if (Builder.loadModuleFile(ModuleFile))
818 // The output buffer, into which the global index will be written.
819 SmallVector<char, 16> OutputBuffer;
821 llvm::BitstreamWriter OutputStream(OutputBuffer);
822 Builder.writeIndex(OutputStream);
825 // Write the global index file to a temporary file.
826 llvm::SmallString<128> IndexTmpPath;
828 if (llvm::sys::fs::createUniqueFile(IndexPath + "-%%%%%%%%", TmpFD,
832 // Open the temporary global index file for output.
833 llvm::raw_fd_ostream Out(TmpFD, true);
838 Out.write(OutputBuffer.data(), OutputBuffer.size());
843 // Remove the old index file. It isn't relevant any more.
844 llvm::sys::fs::remove(IndexPath.str());
846 // Rename the newly-written index file to the proper name.
847 if (llvm::sys::fs::rename(IndexTmpPath.str(), IndexPath.str())) {
848 // Rename failed; just remove the
849 llvm::sys::fs::remove(IndexTmpPath.str());
858 class GlobalIndexIdentifierIterator : public IdentifierIterator {
859 /// \brief The current position within the identifier lookup table.
860 IdentifierIndexTable::key_iterator Current;
862 /// \brief The end position within the identifier lookup table.
863 IdentifierIndexTable::key_iterator End;
866 explicit GlobalIndexIdentifierIterator(IdentifierIndexTable &Idx) {
867 Current = Idx.key_begin();
871 StringRef Next() override {
875 StringRef Result = *Current;
882 IdentifierIterator *GlobalModuleIndex::createIdentifierIterator() const {
883 IdentifierIndexTable &Table =
884 *static_cast<IdentifierIndexTable *>(IdentifierIndex);
885 return new GlobalIndexIdentifierIterator(Table);