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arXiv · 2412.17330

EcoSearch: A Constant-Delay Best-First Search Algorithm for Program Synthesis

Théo Matricon·Nathanaël Fijalkow·Guillaume Lagarde
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Abstract

Many approaches to program synthesis perform a combinatorial search within a large space of programs to find one that satisfies a given specification. To tame the search space blowup, previous works introduced probabilistic and neural approaches to guide this combinatorial search by inducing heuristic cost functions. Best-first search algorithms ensure to search in the exact order induced by the cost function, significantly reducing the portion of the program space to be explored. We present a new best-first search algorithm called EcoSearch, which is the first constant-delay algorithm for pre-generation cost function: the amount of compute required between outputting two programs is constant, and in particular does not increase over time. This key property yields important speedups: we observe that EcoSearch outperforms its predecessors on two classic domains.

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Théo Matricon, Nathanaël Fijalkow, Guillaume Lagarde. 2024-12-23. EcoSearch: A Constant-Delay Best-First Search Algorithm for Program Synthesis. https://arxiv.org/abs/2412.17330

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