[mysterymath]

This has come up off and on, and it's looking increasingly unlikely. I've had to do some nasty surgery to the loop strength reduction pass, and I haven't yet found a way to generalize it.

Still, I'm not ruling it out, it just never seems to be very high on the TODO list. I've also started to do more work upstream whenever the situation calls for it; quite a few of the improvements we've done to LLVM do generalize to other targets, so much of that can and should be upstreamed indepenently.