uops.info is also very handy for x86 ( https://uops.info/table_overview.html ).
But if you are just starting, those may be a bit overwhelming. In that case, check out the official intrinsics guides for x86 from Intel ( https://software.intel.com/sites/landingpage/IntrinsicsGuide... ) and a separate one for Arm ( https://developer.arm.com/architectures/instruction-sets/int... )
[1] https://hn.algolia.com/?q=https%3A%2F%2Fagner.org%2Foptimize...
Not that I'm in favour of developing desktop applications in JavaScript or anything. I don't really think those are a great idea. It's just that there's a lot of intermediate steps between "let's use JavaScript" and "let's worry about using the best x86 opcodes" which are perhaps more sensible than either extreme.
Nobody writes desktop software in a GC'd language that doesn't suffer from noticeable performance issues. There's a reason why people bitch about e.g., Microsoft Teams, and it has a lot to do with language choice.
Programmers choose GC languages because it's what they want, not what users want.