[llvm] [SandboxVectorizer] Define SeedBundle: a set of instructions to be vectorized [retry] (PR #111073)

[via llvm-commits]

https://github.com/vporpo approved this pull request.

Ah yes, this version of `getSlice()` is so much better!

I think we may need couple more checks to exercise `getSlice()` for power-of-2 a bit more (see comments), but other than that it looks good.

https://github.com/llvm/llvm-project/pull/111073