int result = BigIntegerMath.log2(x, mode);
        assertThat(ZERO.setBit(result)).isAtMost(x);
        assertThat(ZERO.setBit(result + 1)).isGreaterThan(x);
      }
    }
  }

  public void testLog2Ceiling() {
    for (BigInteger x : POSITIVE_BIGINTEGER_CANDIDATES) {
      for (RoundingMode mode : asList(CEILING, UP)) {
        int result = BigIntegerMath.log2(x, mode);
        assertThat(ZERO.setBit(result)).isAtLeast(x);