Publication Details
Solving Not-Substring Constraint with Flat Abstraction
Abdulla Parosh
Atig Mohamed (FIT)
Bui Phi Diep (FIT)
Chen Yu-Fang
Wu Zhilin (FIT)
and others
CEGAR, string constraints, strings
Not-substring is currently among the least supported types of string constraints, and existing solvers use only relatively crude heuristics. Yet, not-substring occurs relatively often in practical examples and is useful in encoding other types of constraints. In this paper, we propose a systematic way to solve not-substring using the Counter-Example Guided Abstraction Refinement (CEGAR) framework based on flat abstraction. In such a framework, the domain of string variables is restricted to flat languages and subsequently, the whole constraints can be expressed as linear arithmetic formulae. We show that non-substring constraints can be flattened efficiently, and provide experimental evidence that the proposed solution for not-substring is competitive with the state-of-the-art string solvers.
@inproceedings{BUT182956,
author="Lukáš {Holík} and Parosh {Abdulla} and Mohamed {Atig} and Diep {Bui Phi} and Yu-Fang {Chen} and Zhilin {Wu}",
title="Solving Not-Substring Constraint with Flat Abstraction",
booktitle="Programming Languages and Systems - 19th Asian Symposium, APLAS 2021, Chicago, IL, USA, October 17-18, 2021, Proceedings",
year="2021",
series="13008",
pages="305--320",
publisher="Springer International Publishing",
address="Berlín",
doi="10.1007/978-3-030-89051-3\{_}17",
isbn="978-3-030-89051-3",
url="https://doi.org/10.1007/978-3-030-89051-3\_17"
}