Section: New Software and Platforms


Keywords: Automated deduction - Decision

Scientific Description: SPASS -SATT is an SMT solver for the theories of linear integer arithmetic, linear rational arithmetic and mixed linear arithmetic. It features new tests for the satisfiability of unbounded systems, as well as new algorithms for the detection of integer solutions.

We further investigated the use of redundancy elimination in SAT solving and underlying implementation techniques. Our aim is a new approach to SAT solving that needs fewer conflicts (on average) and is faster than the current state-of-the art solvers. Furthermore, we have developed a new calculus and first prototypical implementation of a SAT solver with mixed OR/XOR clauses.

Functional Description: SPASS-SATT is an SMT solver for linear integer arithmetic, mixed linear arithmetic and rational linear arithmetic.

News Of The Year: SPASS-SATT participated in the SMT competition 2019 in the quantifier free integer and rational linear arithmetic categories. It scored first on rational linear arithmetic and second on integer linear arithmetic. (The winner of the latter category was a portfolio solver that includes SPASS-SATT.) The main improvements are due to an advanced translation to clause normal form, a close interaction between the theory and the SAT solvers, and a new transformation turning unbounded integer problems into bounded integer problems.