[llvm] [LoadStoreVectorizer] Fill gaps in load/store chains to enable vectorization (PR #159388)

[Drew Kersnar via llvm-commits]

dakersnar wrote:

I assume that if we use masked loads, we no longer need the new isLegalToWidenLoads API, and should determine legality in the same way that masked store legality is currently determined?

https://github.com/llvm/llvm-project/pull/159388