Fundamentals of reversible flowchart languages.

This paper presents the fundamentals of reversible flowcharts. Reversible flowcharts are intended to naturally represent the structure and control flow of reversible (imperative) programming languages in a simple computation model in the same way classical flowcharts do for conventional languages. Although reversible flowcharts are superficially similar to classical flowcharts, there are crucial differences: atomic steps are limited to locally invertible operations, and join points require an explicit orthogonalizing conditional expression.