Method finishWrite

bolt/common/memory/HashStringAllocator.cpp:214–254

}

std::pair<HashStringAllocator::Position, HashStringAllocator::Position>
HashStringAllocator::finishWrite(
    ByteOutputStream& stream,
    int32_t numReserveBytes) {
  BOLT_CHECK(
      currentHeader_, "Must call newWrite or extendWrite before finishWrite");
  auto writePosition = stream.writePosition();
  const auto offset = writePosition - currentHeader_->begin();

  BOLT_CHECK_GE(
      offset, 0, "finishWrite called with writePosition out of range");
  BOLT_CHECK_LE(
      offset,
      currentHeader_->usableSize(),
      "finishWrite called with writePosition out of range");

  Position currentPosition = Position::atOffset(currentHeader_, offset);
  if (currentHeader_->isContinued()) {
    free(currentHeader_->nextContinued());
    currentHeader_->clearContinued();
  }
  // Free remainder of block if there is a lot left over.
  freeRestOfBlock(
      currentHeader_,
      writePosition - currentHeader_->begin() + numReserveBytes);
  currentHeader_ = nullptr;

  // The starting position may have shifted if it was at the end of the block
  // and the block was extended. Calculate the new position.
  if (startPosition_.header->isContinued()) {
    auto header = startPosition_.header;
    const auto offset = startPosition_.offset();
    const auto extra = offset - header->usableSize();
    if (extra > 0) {
      auto newHeader = header->nextContinued();
      auto newPosition = newHeader->begin() + extra;
      startPosition_ = {newHeader, newPosition};
    }
  }
  return {startPosition_, currentPosition};
}

void HashStringAllocator::newSlab() {
  constexpr int32_t kSimdPadding = simd::kPadding - sizeof(Header);