find the index of the highest bit set of a 32-bit number without loops obviously

Question

Here\'s a tough one(atleast i had a hard time :P):

find the index of the highest bit set of a 32-bit number without using any loops.

Answer 1

You could do it like this (not optimised):

int index = 0;
uint32_t temp = number;

if ((temp >> 16) != 0) {
    temp >>= 16;
    index += 16;
}

if ((temp >> 8) != 0) {
    temp >>= 8
    index += 8;
}

...