Depends on http://reviews.llvm.org/D16425, only commit after that.
I think we should reverse the dependency and commit this before D16425.
I'm not sure I like this name. Unfortunately, I don't have a better idea. ;) Let me think about this over night, I won't accept this revision before tomorrow anyway.
I think it's more correct to say that this is the amount of bytes this instruction loads from memory. The loaded value doesn't really have a size.