Absolutely, look into your standard library, CPU built-ins and intrinsics first.
However, these tricks are not useless even on modern CPUs. There are scalar instructions for a lot of this stuff, but if you are working with SIMD, several of them are not available.
Recently I wrote bit interleaving stuff with Morton codes. Maybe the scalar instruction would be faster in isolation but I already have my data in SSE registers for other arithmetic so in total it was probably faster. I used the code in this article as a basis.
Re:Bit Twiddling Hacks
by overanalytcl on Saturday August 24, 2024 @03:21PM
(#41340716)
The last link doesn't work.
https://en.wikipedia.org/wiki/X86_Bit_manipulation_instructi...
https://thephd.dev/_vendor/future_cxx/papers/C%20-%20Modern%...