Hi Vladimir,
> opto/loopnode.cpp new is_Phi check was added. Please, explain. When we expand barriers, if we find a null check nearby we move the barrier close to the null check so there's a better chance of converting it to an implicit null check. That happens as part of a pass of loop opts. I think that's where that change comes from but I don't remember the details. In general we need the control that's assigned to a load to not be too conservative. Anyway, that change is not required for correctness. But it looks reasonable to me. Roland.
