tony2001/sort — comment on commit bbf7d63cc313f6b7ea9d0b8206a8edacf820e379
File:  line 0
By Mrrl:

This code is executed once per sorting. I think that a couple of nanoseconds doesn't matter here.
And this code gives another percent or two of total sorting time:

static inline size_t rbnd(size_t len)
{
int k;
if(len<16) return 2;
k=62-CLZ(len);
return 1ULL<<((2*k)/3);
}