Inspired by a post I saw a while ago (reddit thread), I decided to write my own move generator and try to beat it. The goal was to write a single threaded move generator, without hashing or other tools that may improve speed. Just going through every position.
I took some inspiration from Gigantuas' source code, as I had no idea about bmi instructions and templates before. So this was of immense help to achieve my goal! But because I had already written most of the code and found all ways to optimize the logic, refactoring my code with these instructions/templates immediately reached the target.
Running with my AMD Ryzen 7 9800x3d, my engine is able to calculate some positions at more than 4BNodes/s, while Gigantua (compiled with the same compiler and same specs) maxes out at ~3.1BNodes/s
Overall, my engine is about 25% faster, which is as far as I know the fastest move generator.
Another cool thing is that unlike usual perft engines, mine can actually make/unmake moves (with a limited performance impact), so it can be plugged to search the best moves for an actual chess engine! Unfortunately my chess knowledge is too bad to undertake this kind of project. I don't think I would be able to do more than 1500 elo.
I took the liberty of using the same benchmarking to have an exact comparison. Here are the results:
Mine:
Gigantua:
Happy to answer questions as well