THE WEIRD CONCEPT OF 'BRANCHLESS PROGRAMMING'
2025-07-08 01:37 • 19+ min read • #c #branchless
DISCLAIMERS
If you came for readable code, sorry, branchless programming is basically code golf with caffeine.
Code examples are going to be ran in C code.
Drastic measures (e.g. -O3 -ffast-math -march=native -fomit-this-entire-function ) were taken.
0×00 FUNKY INTRODUCTION
Modern CPUs are predictive creatures. They guess what you're about to do, like a nosy algorithm trying to sell you sneakers after you Googled "foot pain." Branch predictors make CPUs fast by speculating on branches... until they guess wrong and everything grinds to a halt for 15,20 cycles.
Branchless programming is how we get around this: we rewrite our code to not branch at all. Instead of jumping to conclusions, we manipulate bits like 1980s assembly gremlins.
WHAT IS A BRANCH
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