The calls into jump tables are generally static, so the jump table itself can be prefetched. The jump table code is then a regular function pointer call, which

The calls into jump tables are generally static, so the jump table itself can be prefetched. The jump table code is then a regular function pointer call, which is also monomorphic and so can be reliably predicted. I'd expect the impact to be small compared to a regular monomorphic function pointer call.