Update RadixSort.cpp

[ferralverrall]

Move if check out of inner while loop

[castano]

Interesting, have you checked whether the compiler actually produces better code? bucketCount is a constant, so the compiler may be doing the same transform for you already.

In our jai implementation I'm using a different approach, evaluating the branch(es) explicitly at compile time:

while (p != pe) {
    h[0][<<p] += 1; p += 1;
    
    #if bucket_count > 1 {
        h[1][<<p] += 1; p += 1;

        #if bucket_count > 2 {
            h[2][<<p] += 1; p += 1;
            h[3][<<p] += 1; p += 1;

            #if bucket_count == 8 {
                h[4][<<p] += 1; p += 1;
                h[5][<<p] += 1; p += 1;
                h[6][<<p] += 1; p += 1;
                h[7][<<p] += 1; p += 1;
            }
        }
    }
}

I imagine that in C++17 you should be able to use 'if constexpr' instead. In any case, if your version produces better code, I'd be happy to commit it.