Publication Details
A Symbolic Algorithm for the Case-Split Rule in String Constraint Solving
string solving
regular model checking
Nielsen transformation
symbolic encoding
Case split is a core proof rule in current decision procedures for the theory of
string constraints. Its use is the primary cause of the state space explosion in
string constraint solving, since it is the only rule that creates branches in the
proof tree. Moreover, explicit handling of the case split rule may cause
recomputation of the same tasks in multiple branches of the proof tree. In this
paper, we propose a symbolic algorithm that significantly reduces such
a redundancy. In particular, we encode a string constraint as a regular language
and proof rules as rational transducers. This allows to perform similar steps in
the proof tree only once, alleviating the state space explosion. In our
preliminary experimental results, we validated that our technique (implemented in
a Python prototype) works in many practical cases where other state-of-the-art
solvers, such as CVC4 or Z3 fail to provide an answer.
@inproceedings{BUT168141,
author="HAVLENA, V. and LENGÁL, O. and CHEN, Y. and TURRINI, A.",
title="A Symbolic Algorithm for the Case-Split Rule in String Constraint Solving",
booktitle="Proceedings of APLAS'20",
year="2020",
journal="Lecture Notes in Computer Science",
number="12470",
pages="343--363",
publisher="Springer Verlag",
address="Heidelberg",
doi="10.1007/978-3-030-64437-6\{_}18",
issn="0302-9743",
url="https://www.fit.vut.cz/research/publication/12347/"
}