Everyone Should Know SIMD (mitchellh.com)
36 points by WadeGrimridge 2 hours ago
qurren 22 minutes ago
I just do gcc -O3 and get SIMD without having to learn it
ashton314 10 minutes ago
In the article, Mitchel mentions how this doesn’t always work. In fact, as someone who’s worked in compiler development, I can say it’s a small miracle when it does work.
forrestthewoods 17 minutes ago
auto-vectorization is not nearly as good as you would hope it to be.
The best SIMD optimizations likely require changing your data format from AoS to SoA.
nylonstrung 4 minutes ago
The one feature in Jonathan Blow's Jai language I really envy is a a single keyword to switch AoS to SoA and visa-versa at comptime
raegis 9 minutes ago
What are AoS and SoA?
Georgelemental 5 minutes ago
nylonstrung 6 minutes ago
formerly_proven 8 minutes ago
And -march=native or at least -march=x86-64-v3 or similar, alternatively identifying relevant functions and manually invoking FMV and uarch specialization via target_clones. Plus non-integer code can generally not be autovectorized in normal-math mode since FP is non-commutative.
Joker_vD 4 minutes ago
Well, then I just prompt Claude and get SIMD without having to learn it /s