I suspect over time as memory latency, bandwidth and branch prediction have become increasingly the hot aspect of CPUs that optimisations put into compilers bef

I suspect over time as memory latency, bandwidth and branch prediction have become increasingly the hot aspect of CPUs that optimisations put into compilers before now often end up improving for the wrong thing. Maintaining sequential reads of memory and ahead of the calculation is now critical for peak performance as is the branch being correctly predicted. Saving calculation time on the ports of the CPU however much less impactful as we mostly struggle to shuttle the work into them to achieve peak performance. Branch predictors are a lot bigger and more capable now than they were and there is every chance when the optimisation for jump tables was tested against the equivalent branch code it outperformed it, but on more recent CPUs the situation reverses.