public static HashFunction goodFastHash(int minimumBits) {
    int bits = checkPositiveAndMakeMultipleOf32(minimumBits);

    if (bits == 32) {
      return Murmur3_32HashFunction.GOOD_FAST_HASH_32;
    }
    if (bits <= 128) {
      return Murmur3_128HashFunction.GOOD_FAST_HASH_128;
    }

    // Otherwise, join together some 128-bit murmur3s
    int hashFunctionsNeeded = (bits + 127) / 128;

    assertEquals(
        Hashing.md5().bits() + Hashing.md5().bits(),
        Hashing.concatenating(asList(Hashing.md5(), Hashing.md5())).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits(),
        Hashing.concatenating(asList(Hashing.md5(), Hashing.murmur3_32())).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits() + Hashing.murmur3_128().bits(),

    long signifRounded = increment ? signifFloor + 1 : signifFloor;
    long bits = (long) (exponent + EXPONENT_BIAS) << SIGNIFICAND_BITS;
    bits += signifRounded;
    /*
     * If signifRounded == 2^53, we'd need to set all of the significand bits to zero and add 1 to
     * the exponent. This is exactly the behavior we get from just adding signifRounded to bits
     * directly. If the exponent is MAX_DOUBLE_EXPONENT, we round up (correctly) to

    for (int bits = 10; bits < 63; bits++) {
      for (int i = 0; i < 100; i++) {
        long p = BigInteger.probablePrime(bits, rand).longValue();
        assertTrue(LongMath.isPrime(p));
      }
    }
  }

  @GwtIncompatible // isPrime is GWT-incompatible
  public void testIsPrimeOnRandomComposites() {
    Random rand = new Random(1);
    for (int bits = 5; bits < 32; bits++) {

    long signifRounded = increment ? signifFloor + 1 : signifFloor;
    long bits = (long) (exponent + EXPONENT_BIAS) << SIGNIFICAND_BITS;
    bits += signifRounded;
    /*
     * If signifRounded == 2^53, we'd need to set all of the significand bits to zero and add 1 to
     * the exponent. This is exactly the behavior we get from just adding signifRounded to bits
     * directly. If the exponent is MAX_DOUBLE_EXPONENT, we round up (correctly) to

  public static HashFunction goodFastHash(int minimumBits) {
    int bits = checkPositiveAndMakeMultipleOf32(minimumBits);

    if (bits == 32) {
      return Murmur3_32HashFunction.GOOD_FAST_HASH_32;
    }
    if (bits <= 128) {
      return Murmur3_128HashFunction.GOOD_FAST_HASH_128;
    }

    // Otherwise, join together some 128-bit murmur3s
    int hashFunctionsNeeded = (bits + 127) / 128;

    assertEquals(
        Hashing.md5().bits() + Hashing.md5().bits(),
        Hashing.concatenating(asList(Hashing.md5(), Hashing.md5())).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits(),
        Hashing.concatenating(asList(Hashing.md5(), Hashing.murmur3_32())).bits());
    assertEquals(
        Hashing.md5().bits() + Hashing.murmur3_32().bits() + Hashing.murmur3_128().bits(),

   * interpreted as an unsigned 64-bit value. Specifically, the sign bit of {@code bits} is
   * interpreted as a normal bit, and all other bits are treated as usual.
   *
   * <p>If the argument is nonnegative, the returned result will be equal to {@code bits},
   * otherwise, the result will be equal to {@code 2^64 + bits}.
   *

        @ParametricNullness T object,
        Funnel<? super T> funnel,
        int numHashFunctions,
        LockFreeBitArray bits);

    /**
     * Queries {@code numHashFunctions} bits of the given bit array, by hashing a user element;
     * returns {@code true} if and only if all selected bits are set.
     */
    <T extends @Nullable Object> boolean mightContain(
        @ParametricNullness T object,

    // GWT doesn't consistently overflow values to make them 32-bit, so we need to force it.
    this.value = value & 0xffffffff;
  }

  /**
   * Returns an {@code UnsignedInteger} corresponding to a given bit representation. The argument is
   * interpreted as an unsigned 32-bit value. Specifically, the sign bit of {@code bits} is
   * interpreted as a normal bit, and all other bits are treated as usual.
   *