[llvm] [LV] Use frozen start value for FindLastIV if needed. (PR #132691)

[Yusuke MINATO via llvm-commits]

yus3710-fj wrote:

Thank you for the fix!

I'd like to backport this fix to the release branch, but I'm not sure how to do it because it seems to depend on some other fixes. I was hoping that someone familiar with this fix could backport it.

https://github.com/llvm/llvm-project/pull/132691