[llvm] [BasicAA] MemCpyOpt fix on tail stackrestore (PR #101352)

[Eli Friedman via llvm-commits]

https://github.com/efriedma-quic commented:

The alternative here is that we declare the tailcallelim transform on llvm.stackrestore illegal.  Which I think is a better idea in case anything else looks at the "tail" marker.

https://github.com/llvm/llvm-project/pull/101352