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 a

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_multiplication https://en.wikipedia.org/wiki/Montgomery_modular_multiplicat...