Department of Intelligent Systems

Sloth: An SMT Solver for String Constraints

Authors:Holík Lukáš, Janků Petr, Lin Anthony W., Rummer Philipp, Vojnar Tomáš
Licence:required - no fee
Keywords:Alternating Finite Automata, Decision Procedure, IC3, String Solving
Sloth is a decision procedure for several relevant fragments of string constraints, including the straight-line fragment and acyclic formulas. In contrast to most other string solvers, Sloth is able to decide satisfiability of constraints combining concatenation, regular expressions, and transduction, all of which are essential in applications. Sloth uses succinct alternating finite-state automata (AFAs) as concise symbolic representations of string constraints, and uses model checking algorithms like IC3 for solving emptiness of the AFA.
The tool and manual is located at and at
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Licence terms:
Free software under the terms of GNU GPLv3 (cf.

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