[llvm] [polly] [IR] Enable dereferenceable-at-point semantics (PR #204795)

[Nikolas Klauser via llvm-commits]

philnik777 wrote:

> Did we ever discuss marking C++ "this" nofree? Not sure if we actually want to do that, but it might come up...

self-deletion is actually a relatively common pattern, so I'm not sure we want to do that (e.g. at least libc++'s `shared_ptr` control blocks delete themselves - I expect other stdlibs to be similar). At the very least there would have to be some escape hatch.

https://github.com/llvm/llvm-project/pull/204795