[llvm] [VPlan] Introduce recipes for VP loads and stores. (PR #87816)

[Florian Hahn via llvm-commits]

fhahn wrote:

Note that this still contains the commit for https://github.com/llvm/llvm-project/pull/87411 as that PR is based on a branch not in `llvm-project`. Will update once https://github.com/llvm/llvm-project/pull/87411 is merged.

https://github.com/llvm/llvm-project/pull/87816