[llvm] LV: generalize profitability criterion over TC (PR #93300)

[David Green via llvm-commits]

https://github.com/davemgreen approved this pull request.

This sounds good to me, so long as it is taking VScaleForTuning into account which I believe it does. LGTM, thanks.

https://github.com/llvm/llvm-project/pull/93300