android/guava/src/com/google/common/primitives/UnsignedLong.java
@Override
  public float floatValue() {
    @SuppressWarnings("cast")
    float fValue = (float) (value & UNSIGNED_MASK);
    if (value < 0) {
      fValue += 0x1.0p63f;
    }
    return fValue;
  }
@Override
  public float floatValue() {
    @SuppressWarnings("cast")
    float fValue = (float) (value & UNSIGNED_MASK);
    if (value < 0) {
      fValue += 0x1.0p63f;
    }
    return fValue;
  }
Returns the value of this {@code UnsignedLong} as a {@code float}, analogous to a widening
primitive conversion from {@code long} to {@code float}, and correctly rounded.