[llvm] [DSE] Mark promise of pre-split coroutine visible to caller (PR #133918)

[Nikita Popov via llvm-commits]

nikic wrote:

I don't have time to look deeply into this right now, but the change looks very concerning to me. Allocas becoming dead at the end of the function is a very core property of allocas. If it does not hold for the promise alloca, it probably should not be an alloca? Is it possible to use a different IR representation?

https://github.com/llvm/llvm-project/pull/133918