[llvm] [LoopVectorize] Enable shuffle padding for masked interleaved accesses (PR #75329)

[Florian Hahn via llvm-commits]

fhahn wrote:

> Can this be done as a part of VPlan-to-VPlan transformation ? For instance, transform

That would be my suggestion as well, the kind of additional maps needed to keep track of additional info is one of the main motivation for VPlan-to-VPlan transformations. This could be a transform replacing a masked interleaved group created originally with an optimized one. I guess the main missing piece is still cost modeling, but I think the main blocker for #67934 has been resolved now so we should be able to make progress on that soon hopefully.

https://github.com/llvm/llvm-project/pull/75329