super bit count

sbc

setup = """
def bitcount (n):
    c = 0
    while n > 0:
        n, r = divmod(n, 2)
        c += r
    return c
def fact(size):
    
    bc = [bitcount(i) for i in range(2**(size))]
    mask = 2**(size)-1
    def sbc(n):
        assert n>0
        c  = 0
        
        while n>0:
            #print(c,hex(n))
            c+=bc[n&mask]
            n>>=size
        return c
    return sbc

sbc= fact(8)
"""
exec(setup)
#print (bitcount(2**29-1))
#print(sbc(2**29-1))
import timeit

print(timeit.timeit("bitcount(2**29 - 1)",setup=setup,number=10**5))
print(timeit.timeit("sbc(2**29 - 1)",setup=setup,number=10**5))