[llvm] [DSE] Fixes bug caused by skipped read clobbers (PR #83181)

[via llvm-commits]

vporpo wrote:

> I experimented a bit to confirm this was indeed the issue and it looks like we should be able to keep using BatchAA, if we avoid deleting instructions that may be cached before the end of DSE, which I sketched here https://github.com/llvm/llvm-project/pull/83411

Thanks for looking into it @fhahn and for figuring out how to fix it without resorting to using AA instead of BatchAA.

https://github.com/llvm/llvm-project/pull/83181