What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?

Question

If I have some integer n, and I want to know the position of the most significant bit (that is, if the least significant bit is on the right, I want to know the position of

Answer 1

Think bitwise operators.

I missunderstood the question the first time. You should produce an int with the leftmost bit set (the others zero). Assuming cmp is set to that value:

position = sizeof(int)*8
while(!(n & cmp)){ 
   n <<=1;
   position--;
}