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arXiv · 2605.14872

String Solving with Stabilization and Transducers (Technical Report)

David Chocholatý·Vojtěch Havlena·Lukáš Holík·Juraj Síč·Michal Šedý
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Abstract

We generalize an efficient automata-based approach to string constraint solving, the stabilization-based method behind the solver Z3-Noodler, to support relational constraints represented by finite-state transducers (useful, for example, for modeling replaceAll constraints). We focus on an efficient treatment of length constraints by reducing the need for expensive concatenation elimination, which is a major bottleneck in automata-based string solving. We also propose powerful heuristics that significantly improve performance in practice. Implemented on top of Z3-Noodler, our method vastly outperforms existing solvers on benchmarks with relational constraints. It solves more instances and runs orders of magnitude faster.

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David Chocholatý, Vojtěch Havlena, Lukáš Holík, Juraj Síč, Michal Šedý. 2026-05-14. String Solving with Stabilization and Transducers (Technical Report). https://arxiv.org/abs/2605.14872

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