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420 points gnabgib | 1 comments | | HN request time: 0.275s | source
1. nullc ◴[] No.44002344[source]
There are many cute binary/logic tricks, if you like them be sure to read Hackers Delight and https://graphics.stanford.edu/~seander/bithacks.html . Once you've studied enough of them you'll find yourself easily coming up with more.

Warning: This may increase or decrease your popularity with fellow programmers, depending on how lucky you are in encountering problems where they make an important performance difference rather than a readability problem for people who have not deeply internalized bit twiddling.

Multiply and mask for varrious purposes is a thing I commonly use in my own code-- it's much more attractive now that it was decades ago because almost all computers we target these days have extremely fast multipliers.

These full-with logic operations and multipliers give you kind of a very parallel computer packed into a single instruction. The only problem is that it's a little tricky to program. :)

At least this one was easy to explain mechanically. Some bit hacks require p-adic numbers and other elements of number theory to explain.