The Taub Faculty of Computer Science Events and Talks

We present a modular and demand-driven analysis of the semantic difference between program versions. Our analysis characterizes initial states for which final states in the program versions are different. It also characterizes states for which the final states are identical. Such characterizations are useful for regression verification, for revealing security vulnerabilities, and for identifying changes in the program's functionality. We are able to prove equivalence or provide an under- and over-approximation of the difference for the unbounded behaviors of the programs.