InvLn2lo
t2 = rlo * InvLn2hi + r * InvLn2lo;
lo = r * InvLn2lo + __builtin_fma(r, InvLn2hi, -hi);
lo = rlo * InvLn2hi + r * InvLn2lo;
t2 = r * InvLn2lo + __builtin_fma(r, InvLn2hi, -t1);