estimate bitcount in mpf_add and mpf_mul in a simpler way, avoiding bctable. this should possibly be slightly faster
estimate bitcount in mpf_add and mpf_mul in a simpler way, avoiding bctable. this should possibly be slightly faster

bjodah/mpmath,klkuhlm/mpmath,fredrik-johansson/mpmath,klkuhlm/mpmath,JensGrabner/mpmath,bjodah/mpmath,JensGrabner/mpmath