int exponent = getExponent(d);
    long bits = doubleToRawLongBits(d);
    bits &= SIGNIFICAND_MASK;
    return (exponent == MIN_EXPONENT - 1) ? bits << 1 : bits | IMPLICIT_BIT;
  }

  static boolean isFinite(double d) {
    return getExponent(d) <= MAX_EXPONENT;
  }

  static boolean isNormal(double d) {
    return getExponent(d) >= MIN_EXPONENT;
  }

  /*

   */
  // #roundIntermediate, java.lang.Math.getExponent, com.google.common.math.DoubleUtils
  @GwtIncompatible
  public static BigInteger roundToBigInteger(double x, RoundingMode mode) {
    x = roundIntermediate(x, mode);
    if (MIN_LONG_AS_DOUBLE - x < 1.0 & x < MAX_LONG_AS_DOUBLE_PLUS_ONE) {
      return BigInteger.valueOf((long) x);
    }
    int exponent = getExponent(x);
    long significand = getSignificand(x);