[llvm] [LV] Vectorize predicated loop-invariant loads via masked load + broadcast (PR #200361)

[Philip Reames via llvm-commits]

preames wrote:

It really seems like what you want here is actually a scalar predicated load.  Maybe it's time to bite the bullet and implement that?  Broadcasting out to the VF type, etc.. is rather arbitrary.  

https://github.com/llvm/llvm-project/pull/200361