[llvm] [DAG] isGuaranteedNotToBeUndefOrPoison - ISD::LOAD nodes are not poison if the LoadSDNode is known to be dereferenceable (PR #160884)

[Nikita Popov via llvm-commits]

nikic wrote:

@RKSimon `!dereferenceable` refers to the *return value* of the load. Correct me if I'm wrong, but I believe the dereferenceable property in SDAG refers to the load *operand* being dereferenceable.

https://github.com/llvm/llvm-project/pull/160884