-O3 -march=native is pretty much all you need and the rest is marginal or circumstantial.
What makes neural networks and learning irrelevant is because there aren't a billion parameters, most parameters don't depend on each other. It is not a search problem. You have the wrong domain.
This is like saying "hey let's crack that password using neural networks, stockfish is so advanced!"
And people have tried auto searching parameters, the results were as I described in my response. Moreover, imagine releasing code and having cluebies complain about trying to make it go faster with -fomit-frame-pointer. The whole idea is wasteful and cringe.