Machine Learning for Quantifier Selection in cvc5
This work addresses a key bottleneck in SMT solving for first-order quantified problems, offering an incremental improvement through efficient ML integration.
The paper tackles the challenge of quantifiers in SMT solving by using machine learning to guide quantifier selection, resulting in a considerable increase in the cvc5 solver's holdout-set performance on first-order problems from the Mizar Mathematical Library.
In this work we considerably improve the state-of-the-art SMT solving on first-order quantified problems by efficient machine learning guidance of quantifier selection. Quantifiers represent a significant challenge for SMT and are technically a source of undecidability. In our approach, we train an efficient machine learning model that informs the solver which quantifiers should be instantiated and which not. Each quantifier may be instantiated multiple times and the set of the active quantifiers changes as the solving progresses. Therefore, we invoke the ML predictor many times, during the whole run of the solver. To make this efficient, we use fast ML models based on gradient boosting decision trees. We integrate our approach into the state-of-the-art cvc5 SMT solver and show a considerable increase of the system's holdout-set performance after training it on a large set of first-order problems collected from the Mizar Mathematical Library.