Studying verification conditions for imperative programs

Program verification tools use verification condition generators to produce logical formulas whose validity implies that the program is correct with respect to its specification. Different tools produce different conditions, and the underlying algorithms have not been properly exposed or explored so far. In this paper we consider a simple imperative programming language, extended with assume and assert statements, to present different ways of generating verification conditions. We study the approaches with experimental results originated by verification conditions generated from the intermediate representation of LLVM.This work is partially financed by the FCT – Fundação para a Ciência e a Tecnologia (Portuguese Foundation for Science and Technology) within project UID/EEA/50014/2013 and by the NII International Internship Program.SFRH/BD/52236/2013