E-SPARK: Automated Generation of Provably Correct Code from Formally Verified Designs

Abstract

An approach to generating provably correct sequential code from formallydeveloped algorithmic designs is presented. Given an algorithm modelledin the Event-B formalism, we automatically translate the design into the SPARKprogramming language. Our translation builds upon Abrial’s approach to the developmentof sequential programs from Event-B models. However, as well as generatingcode, our approach also automatically generates code level specifications, i.e.SPARK pre- and post-conditions, along with loop invariants. In terms of the SPARKproof tools, having the loop invariants increases verification automation. A prototype,known as E-SPARK, has been implemented as a plugin for the Rodin Platform(Event-B toolkit), and tested on a range of examples, i.e. searching, sorting andnumeric calculations.