[cardiffspaceman]

One of my favorite JIT techniques from the era is PIC, polymorphic inline caching. A method send (virtual function call) would be statically coded to call the hottest implementation of a virtual function. The virtual function itself would check that the incoming object had the right type. If not, the fully polymorphic dispatch mechanism would kick in. Statistics would be tracked and could lead to a decision to overwrite the static call with a call to the new hot implementation. I think this was demonstrated on Strongtalk.