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.
Mon 8 AprDisplayed time zone: Amsterdam, Berlin, Bern, Rome, Stockholm, Vienna change
10:30 - 12:30 | |||
10:30 30mTalk | Decomposing Farkas Interpolants TACAS Martin Blicha USI Lugano, Switzerland, Antti Hyvärinen , Jan Kofroň Charles University, Natasha Sharygina USI Lugano, Switzerland Link to publication | ||
11:00 30mTalk | Parallel SAT Simplification on GPU Architectures TACAS Link to publication | ||
11:30 30mTalk | Encoding Redundancy for Satisfaction-Driven Clause LearningBest paper nomination TACAS Marijn Heule The University of Texas at Austin, Benjamin Kiesl CISPA Helmholtz Center for Information Security, Armin Biere Johannes Kepler University Linz Link to publication | ||
12:00 30mTalk | WAPS: Weighted and Projected Sampling TACAS Rahul Gupta , Shubham Sharma , Subhajit Roy IIT Kanpur, India, Kuldeep S. Meel National University of Singapore Link to publication |