I've been using the IFV tool for quite sometime now and I notice that when I run FSM assertions under AFA, No deadlock assertions remain explored while the others pass easily. Is there anyway to improve this?
besides increasing the effort and partitioning the design there is not much you can do. Note that the FSM NoDeadlock check is a very complicated check that has to verify the FSM in context of all other state bits as well as excluding unfairness on all inputs.
There is a change in FSM NoDeadlock checks starting in 13.1 that will improve performance significantly, at the cost of failures due to unfair input behavior. I recommend to try that and share the experience.