[libeclipse]

> In this case, a divide by 3 is equivalent to multiplying by 0x55555556 and then taking the top half of the output.

What the fuck. That's amazing!

[chris_overseas]

In more general terms, take a look at Montgomery multiplication[1] which is where this trick originates. It's a common technique used by compilers to optimise away divisions.

[1] https://en.wikipedia.org/wiki/Montgomery_modular_multiplicat...

[vardump]

In that case, fixed point arithmetic might blow your mind. :)

https://en.wikipedia.org/wiki/Fixed-point_arithmetic