- Rewrite mem ops to only modify regs after exception path
- Throw & catch logic for interpreter that raises the exception
- Re-enabled some commented mmu code
Reicast doesn't support exceptions yet, so this isn't of much use now,
and is intended mostly as documentation. nullDC used some call stack
hooking magic to handle exceptions, which was never generic and clean
enough to be worth the effort to port to Reicast.