Someone well-versed in assembly can still do much better than the compiler in many cases over reasonably small function. You could of course do better for large

Someone well-versed in assembly can still do much better than the compiler in many cases over reasonably small function. You could of course do better for large functions too, but at some point the cost becomes prohibitive: if you're going to do this, stick to a few hotspots which are as compact as possible.