Publication Details
Sky Is Not the Limit: Tighter Rank Bounds for Elevator Automata in Buchi Automata Complementation
Lengál Ondřej, Ing., Ph.D. (DITS)
Šmahlíková Barbora, Ing. (RG VERIFIT)
Büchi automata, complementation, elevator automata, model checking
We propose several heuristics for mitigating one of the main causes of
combinatorial explosion in rank-based complementation of Büchi automata (BAs):
unnecessarily high bounds on the ranks of states. First, we identify elevator
automata, which is a large class of BAs (generalizing semi-deterministic BAs),
occurring often in practice, where ranks of states are bounded according to the
structure of strongly connected components. The bounds for elevator automata also
carry over to general BAs that contain elevator automata as a sub-structure.
Second, we introduce two techniques for refining bounds on the ranks of BA states
using data-flow analysis of the automaton. We implement out techniques as an
extension of the tool Ranker for BA complementation and show that they indeed
greatly prune the generated state space, obtaining significantly better results
and outperforming other state-of-the-art tools on a large set of benchmarks.
@inproceedings{BUT175859,
author="Vojtěch {Havlena} and Ondřej {Lengál} and Barbora {Šmahlíková}",
title="Sky Is Not the Limit: Tighter Rank Bounds for Elevator Automata in Buchi Automata Complementation",
booktitle="Proceedings of TACAS'22",
year="2022",
journal="Lecture Notes in Computer Science",
number="13244",
pages="118--136",
publisher="Springer Verlag",
address="Munich",
doi="10.1007/978-3-030-99527-0\{_}7",
isbn="978-3-030-99526-3",
issn="0302-9743"
}