[llvm] [NFC][LV]: Differentiate between Pred and Unpred masked operations. (PR #169509)

[Florian Hahn via llvm-commits]

https://github.com/fhahn commented:

> Hi @fhahn
>I'm going to land this patch soon. If you added comments on the draft patch related to this work, I will resolve them in a future patch.
> Thanks for your help.

I had some time to take a closer look at the draft, but it is not entirely clear to me how the new changes are used exactly. Could you add a brief comment for the use context? I think I am missing something, because it seems the tests in the draft seem to also pass when remove the extra set and just use the original code using `MaskedOp`

https://github.com/llvm/llvm-project/pull/169509