[llvm] [Loads] Check loop-varying pointer in isDereferenceableAndAlignedInLoop. (PR #120962)

[Nikita Popov via llvm-commits]

nikic wrote:

A basic way to make the deref assumption handling conservatively correct is to add a V->canBeFreed() check (same as we do for call return values), but I suspect if we do that it probably also won't be useful for the motivating cases anymore.

https://github.com/llvm/llvm-project/pull/120962