[llvm] [AArch64] Add MATCH loops to LoopIdiomVectorizePass (PR #101976)

[David Sherwood via llvm-commits]

https://github.com/david-arm commented:

The patch is looking mostly good. I've still got a bit more to review, but at the moment there is a serious bug with this so can you hold off landing this until it's fixed? The inner loop can exit early before you've loaded the rest of the needle so it needs memory checks before entering the vector loop to ensure the needle doesn't cross a page boundary.

https://github.com/llvm/llvm-project/pull/101976