Mastodawn

This 👇🏽 is good 👌🏽:

“A Leap Year Check In Three Instructions”, Falk Hüffner (https://hueffner.de/falk/blog/a-leap-year-check-in-three-instructions.html).

Via HN: https://news.ycombinator.com/item?id=43999748

On Lobsters: https://lobste.rs/s/ybjgex/leap_year_check_three_instructions

#Optimization #Assembly #Compilers #GCC #Math #LeapYear #GregorianCalendar #BitTwiddling #Speed

A leap year check in three instructions

How to test for leap years (until year 102499) in the proleptic Gregorian calendar with just three 32-bit instructions, with detailed explanation of the bit-level tricks.

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रञ्जित (Ranjit Mathew)May 17, 2025

The mother lode of #BitTwiddling tips (apart from the #book “Hacker’s Delight”, by Henry S. Warren Jr, and “HAKMEM” by the MIT hackers):

“Bit Twiddling Hacks”, Sean Eron Anderson (https://graphics.stanford.edu/~seander/bithacks.html).

On HN: https://hn.algolia.com/?dateRange=all&page=0&prefix=false&query=Bit%20Twiddling%20Hacks&sort=byPopularity&type=story

#Math #Optimization #Compilers