[_dps]

Just a personal anecdote, but it regularly makes a substantial (like 2x+) difference for me in tight linear algebra loops. It seems to be required if you want to coax clang to emit vfmad instructions for common C linear algebra idioms. Narrow use case, I know, but it can definitely make a big difference in some domains.

[tachyonbeam]

I'll take your word for it. I guess I live in a world where the code I see is rarely tight algebra loops, but I can see that in certain domains you would definitely care.