[llvm] [MemCpyOpt] fix incorrect handling of lifetime markers (PR #143782)

[Nikita Popov via llvm-commits]

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nikic wrote:

The changes here break the intent of the test. I've adjusted it in https://github.com/llvm/llvm-project/commit/a8c6fb4cb8e686f733e022afc549bc085d1558f4 to preserve the existing behavior with the lifetimes fixed.

https://github.com/llvm/llvm-project/pull/143782