Alexsa - Algorithm Explanation by Shape Analysis - Extensions to the TVLA System

Abstract

Algorithm explanation visualizes programs for teaching, debugging,optimization, and verification purposes. In this thesis we use shape analysis with 3-valued Kleene logic and the TVLA implementation of this analysis to analyze programs with respect to dynamic data structures. Our tool Alexsa features an easy to use interface for the visualization, with simultaneous code view and heap content representation. We implement an automatic pseudo code generation for improved readability, a well-defined algorithm for presenting the visual execution of programs in an interesting way, smooth transitions between the single states, and a number of additional tools for verification and debugging of the analyzed programs.