[llvm] [DSE] Split memory intrinsics if they are dead in the middle (PR #75478)

[via llvm-commits]

https://github.com/DianQK commented:

LGTM. Thanks! But I cannot review about atomic. :)
I mean that using a smaller align to reduce dead memory intrinsic: https://alive2.llvm.org/ce/z/LiGZUd. Maybe this could be another PR.

https://github.com/llvm/llvm-project/pull/75478