[llvm] [AA] Refine ModRefInfo taking into account `errnomem` location (PR #157495)

[Alex Bradbury via llvm-commits]

asb wrote:

I've also just bisected a failure to this https://lab.llvm.org/buildbot/#/builders/214/builds/622 - the run containing https://github.com/llvm/llvm-project/commit/09966960c692be63b192448e8c2b6bfebad3c3b8 hasn't completed yet but has got past the point it should have failed at, so it appears to have fixed the issue.

https://github.com/llvm/llvm-project/pull/157495