Yes. this is doing to infamous division by 10 using bit shifts as you will find in hacker's delight: http://www.hackersdelight.org/divcMore.pdf http://www.hacke

Yes. this is doing to infamous division by 10 using bit shifts as you will find in hacker's delight: http://www.hackersdelight.org/divcMore.pdf http://www.hackersdelight.org/divcMore.pdf. You may notice that when you divide num by 10 you get a quotient q and a remainder r: num = q*10 + r Once you get q, you can solve for r as r = num - q*10 So this is how you get r and q: q = (num >> 1) + (num >> 2); q = q + (q >> 4); q = q + (q >> 8); q = q + (q >> 16); q = q >> 3; r = num - q*10; q = q + ((r + 6) >> 4) voila!