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Re:Bit Twiddling Hacks by zokier on Friday August 23, 2024 @05:51AM (#41327615)
It's worth noting that modern x86 CPUs have specialized extensions for bit manipulation. Furthermore C23 added stdbit.h that has some operations for bit manipulation

https://en.wikipedia.org/wiki/X86_Bit_manipulation_instructi...

https://thephd.dev/_vendor/future_cxx/papers/C%20-%20Modern%...

Re:Bit Twiddling Hacks by exDM69 on Friday August 23, 2024 @10:59AM (#41329573)
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.