Tag: bitmath

Population Count in Java

How do you count the bits in a 32 bit integer? Since this is possible in a single instruction, popcntd, which is exposed by an intrinsic method in Java and several other languages, this is a completely academic question. Nevertheless, however futile, deriving an efficient expression is instructive. A naive approach would be to check

Bit Twiddling Blog Posts

This is a list of blog posts to read if you like bit twiddling and some basic maths. I would like to improve this list over time – if you have a post similar to these please provide a link in the comments. Table of basic reversible integer operations – Marc B. Reynolds looks at