Method parseModuleStringTable

src/lib/Bitcode/Reader/BitcodeReader.cpp:5620–5678

Parse the module string table block into the Index. This populates the ModulePathStringTable map in the index.

// Parse the  module string table block into the Index.
// This populates the ModulePathStringTable map in the index.
Error ModuleSummaryIndexBitcodeReader::parseModuleStringTable() {
  if (Stream.EnterSubBlock(bitc::MODULE_STRTAB_BLOCK_ID))
    return error("Invalid record");

  SmallVector<uint64_t, 64> Record;

  SmallString<128> ModulePath;
  ModuleSummaryIndex::ModuleInfo *LastSeenModule = nullptr;

  while (true) {
    BitstreamEntry Entry = Stream.advanceSkippingSubblocks();

    switch (Entry.Kind) {
    case BitstreamEntry::SubBlock: // Handled for us already.
    case BitstreamEntry::Error:
      return error("Malformed block");
    case BitstreamEntry::EndBlock:
      return Error::success();
    case BitstreamEntry::Record:
      // The interesting case.
      break;
    }

    Record.clear();
    switch (Stream.readRecord(Entry.ID, Record)) {
    default: // Default behavior: ignore.
      break;
    case bitc::MST_CODE_ENTRY: {
      // MST_ENTRY: [modid, namechar x N]
      uint64_t ModuleId = Record[0];

      if (convertToString(Record, 1, ModulePath))
        return error("Invalid record");

      LastSeenModule = TheIndex.addModule(ModulePath, ModuleId);
      ModuleIdMap[ModuleId] = LastSeenModule->first();

      ModulePath.clear();
      break;
    }
    /// MST_CODE_HASH: [5*i32]
    case bitc::MST_CODE_HASH: {
      if (Record.size() != 5)
        return error("Invalid hash length " + Twine(Record.size()).str());
      if (!LastSeenModule)
        return error("Invalid hash that does not follow a module path");
      int Pos = 0;
      for (auto &Val : Record) {
        assert(!(Val >> 32) && "Unexpected high bits set");
        LastSeenModule->second.second[Pos++] = Val;
      }
      // Reset LastSeenModule to avoid overriding the hash unexpectedly.
      LastSeenModule = nullptr;
      break;
    }
    }
  }
  llvm_unreachable("Exit infinite loop");