ETAPS 2019
Sat 6 - Thu 11 April 2019 Prague, Czech Republic
Sun 7 Apr 2019 16:00 - 16:30 at S4 (HCVS) - IV Chair(s): Nikolaj Bjørner

Modern verification commonly models software with Boolean logic and a system of linear inequalities over reals and over-approximates the reachable states of the model with Craig interpolation to obtain, for example, candidates for inductive invariants. Interpolants for the linear system can be efficiently constructed from a Simplex refutation by applying the Farkas’ lemma. However, this approach results in the worst case in incompleteness, since Farkas interpolants do not always suit the verification task. This work introduces the decomposed interpolants, a fundamental extension of the Farkas interpolants obtained by identifying and separating independent components from the interpolant structure using methods from linear algebra. We integrate our approach to the model checker Sally and show experimentally that a portfolio of decomposed interpolants results in immediate convergence on instances where state-of-the-art approaches diverge. Being based on the efficient Simplex method, the approach is very competitive also outside these diverging cases.

Sun 7 Apr

Displayed time zone: Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna change

16:00 - 18:00
Chair(s): Nikolaj Bjørner Microsoft Research
Decomposing Farkas Interpolants
Martin Blicha USI Lugano, Switzerland, Antti Hyvärinen , Jan Kofroň Charles University, Natasha Sharygina USI Lugano, Switzerland
File Attached
Experience report
Report on the CHC competition
Grigory Fedyukovich Princeton University