Performance impact of the modular architecture in the incremental SGLR parsing algorithm

Abstract

JSGLR2 is a modular Java implementation of the SGLR parsing algorithm that supports systematic benchmarking and improvement of its several parsing variants. By splitting the code into several components, they can be tested in isolation and thus optimized more effortlessly. The modular architecture, although beneficial for efficiently identifying and implementing optimizations, negatively impacts the performance of the parsing algorithm. This paper aims to measure the overhead introduced by the code architecture for one of the variants, more specifically the incremental variant, which combines incremental parsing with SGLR parsing. It does so by comparing the original implementation with a version with the modularity removed. The evaluation is done on programming languages used in practice: Java, WebDSL and SDF3. The results show that the inlined parser outperforms the previous one, achieving speedups of up to 16% in batch parsing and up to 10% in incremental parsing.