Bit-Twiddling

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Bit-twiddling is a family of techniques used in manipulating integers in a non-obvious manner in order to obtain a result either more quickly or with less code. Bit-twiddling is often associated with bitboards, but there are both easy-to-read bitboard implementations and difficult-to-read implementations of other board representations.

=Bit-Twiddling related to Bitboards= =Bit-Manipulation=
 * BitScan
 * Flipping Mirroring and Rotating
 * Kogge-Stone
 * Obtaining and Clearing the Least Significant Bit (LS1B)
 * Population Count
 * Traversing Subsets of a Set
 * ABM
 * BMI1
 * BMI2
 * General Setwise Operations
 * TBM

=Forum Posts=
 * Bit twiddlement question: greater of two popcounts by Zach Wegner, CCC, August 06, 2009
 * Bit twiddling question, part 2: arbitrary bitscan order by Zach Wegner, CCC, August 11, 2009
 * Bit position hack by nak3c, OpenChess Forum, September 01, 2013

=Important online resources= Online Papers by Donald Knuth:
 * Preprints of Recent Papers including dancing links
 * The Art of Computer Programming
 * Vol 4 as Pre-Fascicle PostScripts:

Online Papers by Henry S. Warren, Jr. =Other Bit-Twiddling resources=
 * Pre-Fascicle 0b (Boolean basics)
 * Pre-Fascicle 0c (Boolean evaluation)
 * Pre-Fascicle 1a (Bitwise tricks and techniques)
 * Hacker’s Delight, 2nd Edition
 * Sample section of Hacker's Delight, Chapter 2 Basics (pdf)
 * C code for most of the programs that appear in HD
 * Michael Beeler, Bill Gosper, Rich Schroeppel (1972). HAKMEM, Memo 239, Artificial Intelligence Laboratory, Massachusetts Institute of Technology
 * HAKMEMC -- HAKMEM Programming hacks in C by Alan Mycroft
 * HAKMEM from Wikipedia


 * Matters Computational - ideas, algorithms, source code (pdf) Ideas and Source Code by Jörg Arndt
 * The Aggregate Magic Algorithms by Hank Dietz
 * Bit Twiddling Hacks by Sean Eron Anderson
 * the bit twiddler by Stephan Brumme
 * Programming pages of Jasper Neumann
 * GitHub - keon/awesome-bits: A curated list of awesome bitwise operations and tricks
 * Bitwise Optimization in Java: Bitfields, Bitboards, and Beyond by Glen Pepicelli, (Wayback Machine, 2005), O'Reilly's OnJava.com » Java, Bitboards
 * math/bits: an integer bit twiddling library · Issue #18616 · golang/go · GitHub » Go (Programming Language)

=External Links=
 * Bit twiddler from Wikipedia
 * Bit manipulation from Wikipedia
 * bit twiddling ... from Random thoughts blog by Mridul Muralidharan
 * Twiddling the Bits by David Stafford
 * NHØP & Tania Maria - Baião improvisado, YouTube Video

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