h2 += h1;

      h1 = fmix64(h1);
      h2 = fmix64(h2);

      h1 += h2;
      h2 += h1;

      return HashCode.fromBytesNoCopy(
          ByteBuffer.wrap(new byte[CHUNK_SIZE])
              .order(ByteOrder.LITTLE_ENDIAN)
              .putLong(h1)
              .putLong(h2)
              .array());
    }

    private static long fmix64(long k) {
      k ^= k >>> 33;