Method writeTypeSection

lib/Bytecode/Writer/BytecodeWriter.cpp:347–385

  }

  LogicalResult writeTypeSection(raw_ostream &stream) {
    SmallVector<char> buffer;
    llvm::raw_svector_ostream sectionStream(buffer);
    EncodingWriter sectionWriter(sectionStream);

    sectionWriter.writeVarInt(typeList.size());
    // Align the type section
    uint64_t alignmentNeeded = alignof(uint32_t);
    sectionWriter.alignTo(alignmentNeeded);

    // Save the current position to fix up offsets later.
    auto offsetsPtr = sectionWriter.tell();

    // Reserve space for the offset table (filled later).
    for (size_t i = 0; i < typeList.size(); ++i)
      sectionWriter.writeLE<uint32_t>(0);

    // Write each type and record its starting offset.
    SmallVector<uint32_t> finalOffsets;
    finalOffsets.reserve(typeList.size());

    uint32_t running = 0;
    for (Type type : typeList) {
      finalOffsets.push_back(running);
      auto before = sectionWriter.tell();
      if (failed(serializeType(type, sectionWriter)))
        return failure();
      running += static_cast<uint32_t>(sectionWriter.tell() - before);
    }

    // Copy the pre-computed offsets into the reserved slot.
    std::copy_n(finalOffsets.begin(), finalOffsets.size(),
                reinterpret_cast<uint32_t *>(buffer.data() + offsetsPtr));

    writeSectionHeader(stream, Bytecode::Section::Type, buffer.size(),
                       sectionWriter.getRequiredAlignment());
    stream.write(buffer.data(), buffer.size());
    return success();
  }

  /// Helper function to write the index of a given type to the writer.
  LogicalResult writeTypeIndex(Type type, EncodingWriter &writer) {