[llvm] [LoopUnroll] Remove redundant debug instructions after blocks have been merged (PR #91246)

[via llvm-commits]

coderchenlin wrote:

@slackito @aeubanks , Hi, guys, I'm sorry to bother you. I just give a more targeted solution for fixing compile-time. and I also test my case and your provided case, the compile-time is Ok.  Could you help me to review this change, and give some advices?



[Uploading slowdown.ll.txt…]()
[before.time-trace.json](https://github.com/llvm/llvm-project/files/15234414/before.time-trace.json)
[after.time-trace.json](https://github.com/llvm/llvm-project/files/15234415/after.time-trace.json)



https://github.com/llvm/llvm-project/pull/91246