private fun ByteString.binarySearch(
      labels: Array<ByteString>,
      labelIndex: Int,
    ): String? {
      var low = 0
      var high = size
      var match: String? = null
      while (low < high) {
        var mid = (low + high) / 2
        // Search for a '\n' that marks the start of a value. Don't go back past the start of the
        // array.

  position: Int,
  limit: Int,
  compare: (Int) -> Int,
): Int {
  // Do the binary searching bit.
  var low = position
  var high = limit - 1
  while (low <= high) {
    val mid = (low + high) / 2
    val compareResult = compare(mid)
    when {
      compareResult < 0 -> high = mid - 1
      compareResult > 0 -> low = mid + 1
      else -> return mid // Match!
    }
  }

    return val ^ (val >>> 47);
  }

  /** Implementation of Hash128to64 from util/hash/hash128to64.h */
  @VisibleForTesting
  static long hash128to64(long high, long low) {
    long a = (low ^ high) * K3;
    a ^= a >>> 47;
    long b = (high ^ a) * K3;
    b ^= b >>> 47;
    b *= K3;
    return b;
  }

  /**
   * Computes intermediate hash of 32 bytes of byte array from the given offset. Results are

   *   <li>If the first character was a high surrogate value, then an attempt is made to read the
   *       next character.
   *       <ol>
   *         <li><b>If the end of the sequence was reached, the negated value of the trailing high
   *             surrogate is returned.</b>
   *         <li><b>If the next character was a valid low surrogate, the code point value of the
   *             high/low surrogate pair is returned.</b>

   *   <li>If the first character was a high surrogate value, then an attempt is made to read the
   *       next character.
   *       <ol>
   *         <li><b>If the end of the sequence was reached, the negated value of the trailing high
   *             surrogate is returned.</b>
   *         <li><b>If the next character was a valid low surrogate, the code point value of the
   *             high/low surrogate pair is returned.</b>

    assertThat(UnsignedLongs.compare(0xffffffffffffffffL, 0)).isGreaterThan(0);

    // both with high bit set
    assertThat(UnsignedLongs.compare(0xff1a618b7f65ea12L, 0xffffffffffffffffL)).isLessThan(0);
    assertThat(UnsignedLongs.compare(0xffffffffffffffffL, 0xff1a618b7f65ea12L)).isGreaterThan(0);

    // one with high bit set
    assertThat(UnsignedLongs.compare(0x5a4316b8c153ac4dL, 0xff1a618b7f65ea12L)).isLessThan(0);

| [OpenJSSE]       |         | ✅           | [OpenJDK]       | OpenJDK backport.                                            |
| [Corretto]       | ✅      | ✅           | [OpenSSL]       | Amazon's high-performance provider. [Tracking bug.][bug5592] |

All providers support HTTP/1.1 and TLSv1.2.


[BoringSSL]: https://boringssl.googlesource.com/boringssl/
[Bouncy Castle]: https://www.bouncycastle.org/java.html

    return val ^ (val >>> 47);
  }

  /** Implementation of Hash128to64 from util/hash/hash128to64.h */
  @VisibleForTesting
  static long hash128to64(long high, long low) {
    long a = (low ^ high) * K3;
    a ^= a >>> 47;
    long b = (high ^ a) * K3;
    b ^= b >>> 47;
    b *= K3;
    return b;
  }

  /**
   * Computes intermediate hash of 32 bytes of byte array from the given offset. Results are

    return fmix(h1, Ints.BYTES);
  }

  @Override
  public HashCode hashLong(long input) {
    int low = (int) input;
    int high = (int) (input >>> 32);

    int k1 = mixK1(low);
    int h1 = mixH1(seed, k1);

    k1 = mixK1(high);
    h1 = mixH1(h1, k1);

    return fmix(h1, Longs.BYTES);
  }

  @Override
  public HashCode hashUnencodedChars(CharSequence input) {

  @Override
  void writeDouble(double v);

  @Override
  void writeChars(String s);

  @Override
  void writeUTF(String s);

  /**
   * @deprecated This method is dangerous as it discards the high byte of every character. For
   *     UTF-8, use {@code write(s.getBytes(StandardCharsets.UTF_8))}.
   */
  @Deprecated
  @Override
  void writeBytes(String s);