Reversible execution and visualization of programs with LEONARDO

In this paper we present LEONARDO, an integrated environment for software v isualization that allows the user to edit, compile, execute, and animate ge neral-purpose C programs. LEONARDO relies on a logic-based approach to visu alization: a mapping between concrete and abstract data structures can be d eclared through a logic visualization language and animations are conceived as reflecting formal properties of algorithms. LEONARDO is able to automat ically detect visual events during the execution of programs and simplifies the creation of visualizations according to an incremental approach. Moreo ver, it guarantees the complete reversibility of computations, bounded only by the potentiality of the working machine, and appears simple to be used. The latest version of LEONARDO is currently available over the Internet at the URL http://www.dis.uniroma1.it/similar to demetres/Leonardo/. (C) 2000 Academic Press.