Do you have benchmarks that show the hand rolled jump table has a significant impact?

The only reason this raises an eyebrow is that I've seen conflicting anec/data on this, depending pretty hard on target microarchitecture and the program itself.

Sadly that was one of the things I did benchmark, but didn't write down the results. I read a lot that naive switch is faster because the compiler knows how to optimise them better, but for my architecture and benchmarks the computed gotos were faster