%0  param     0             range [0, 15]  safe=True
%1  const     4             range [4, 4]  safe=True
%2  mul      %0, %1       range [0, 60]  safe=True
%3  param     1             range [0, 3]  safe=True
%4  add      %2, %3       range [0, 63]  safe=True
%5  floordiv %4, %1       range [0, 15]  safe=True

big in [0, 2^30], big*4: range [-2147483648, 2147483647] safe=False   (4*2^30 = 2^32 does not fit, so it wraps)
(big*4)//4 simplified: FLOORDIV (unchanged, because the guard says the split could be wrong)
