SymDiff is a tool for performing differential program verification. Differential program verification concerns with specifying and proving interesting properties over program differences, as opposed to the program itself. Such properties include program equivalence, but can also capture more general differential/relational properties. SymDiff provides a specification language to state such differential (two-program) properties using the concept of mutual summaries that can relate procedures from two versions. It also provides proof system for checking such differential specifications along with the capability of generating simple differential invariants.
The tool is language-independent and works at the level of Boogie programming language. The intent is to be able to target various source languages (C, C++, .NET, x86) using translators to Boogie. We currently have a front end for C and Boogie programs for download.
The source code of SymDiff is on Codeplex. This part deals purely with Boogie programs.
The following tutorial slides provides an overview of SymDiff, as of April 2016: