Grammar-Constrained (CFL) Reachability: Subcubic Preprocessing, Indexing Trade-offs, and Structured Decoding Semantics
Abstract
We study the problem of grammar-constrained context-free language reachability in graphs, focusing on complexity and empirical performance. We present an algorithmic framework for evaluating reachability queries constrained by context-free grammars, and analyze its theoretical runtime bounds. To complement our theoretical results, we conduct an extensive empirical evaluation on a comprehensive benchmark of real-world schemas, comparing different algorithmic variants and reporting performance trade-offs. Our results highlight the impact of grammar structure and graph characteristics on reachability computation, and provide guidance for selecting efficient approaches in practice.
Cite
@article{arxiv.2602.23401,
title = {Grammar-Constrained (CFL) Reachability: Subcubic Preprocessing, Indexing Trade-offs, and Structured Decoding Semantics},
author = {Faruk Alpay and Levent Sarioglu},
journal= {arXiv preprint arXiv:2602.23401},
year = {2026}
}
Comments
19 pages, 4 figures, 4 tables. Code and empirical data available at: https://github.com/farukalpay/grammar-constrained-cfl-reachability-empirical