assertEquals(exp + 1, DoubleMath.log2(x, mode));
        assertEquals(exp, DoubleMath.log2(y, mode));
      }
    }
  }

  @GwtIncompatible // DoubleMath.log2(double, RoundingMode)
  public void testRoundLog2Exact() {
    for (double x : POSITIVE_FINITE_DOUBLE_CANDIDATES) {
      boolean isPowerOfTwo = StrictMath.pow(2.0, DoubleMath.log2(x, FLOOR)) == x;
      try {
        int log2 = DoubleMath.log2(x, UNNECESSARY);