[llvm] [LV] Add initial legality checks for early exit loops with side effects (PR #145663)

[Graham Hunter via llvm-commits]

huntergr-arm wrote:

> Hi @huntergr-arm
> 
> We see crashes with this patch. `opt --passes=loop-vectorize bbi-110488.ll -o /dev/null` fails with

Thanks for the report, should be fixed by 54fc5367f63cca8e011d93bbd55764b0a7ecbbd5

https://github.com/llvm/llvm-project/pull/145663