[llvm] [MemCpyOpt] lifetime markers reconstruction for Stack-move optimization (PR #68990)

[Kohei Asano via llvm-commits]

khei4 wrote:

> @khei4 is there a PR here for https://reviews.llvm.org/D159075, or did that patch get lost?

Thanks! Not yet. I'm now preparing to rebase the patch, and it'll be ported with more descriptions to Github in a few weeks :)
I think it's better to separate here the lifetime-marker missing regression, and the above patch, improving the algorithm.

https://github.com/llvm/llvm-project/pull/68990