Comment by wildzzz
14 hours ago
Dreadfully slow for integer math but probably some similar performance to something like a CORDIC for specific operations. If you can build an FPU that does exp() and ln() really fast, it's simple binary tree traversal to find the solution.
You already have an FPU that approximates exp() and ln() really fast, because float<->integer conversions approximate the power 2 functions respectively. Doing it accurately runs face-first into the tablemaker's dilemma, but you could do this with just 2 conversions, 2 FMAs (for power adjustments), and a subtraction per. A lot of cases would be even faster. Whether that's worth it will be situational.
What are some of your favorite sources to dig into this field as a whole?
Anything discussing fast inverse sqrt will go over the logarithmic side [0], as it's the key insight behind that code. Exp is just the other direction. It's not widely documented in text otherwise, to my knowledge.
[0] https://github.com/francisrstokes/githublog/blob/main/2024/5...