std::vector<uint8_t> data;
    for (mlir::APInt v : attr.getValues<mlir::APInt>()) {
      data.emplace_back(static_cast<uint8_t>(*(v.getRawData())));
    }
    auto packed_buffer = tflite::PackInt4ValuesDensely(data);
    if (use_buffer_offset_) {
      buffer_data_map_[index] =
          std::string(packed_buffer.begin(), packed_buffer.end());
      return tflite::CreateBuffer(builder_, 0, 1, 1);
    } else {