[clang] [llvm] [Loads] Check context instruction for context-sensitive derefability (PR #109277)

[Nikita Popov via cfe-commits]

nikic wrote:

> @nikic I mean not in theory but currently. I don't see those (except allocas) handled anywhere unless I'm missing something?

The `I &&` part handles those. If it's a global or argument (thus not an instruction) we'll fall through to the return true.

https://github.com/llvm/llvm-project/pull/109277