Rewrite System Showdown: Stochastic Search vs. EqSat

TL;DR

This paper compares equality saturation and stochastic search methods for program optimization across five benchmarks to evaluate their relative effectiveness.

Contribution

It provides the first rigorous comparison between equality saturation and stochastic search for equational program optimization.

Findings

Equality saturation and stochastic search perform differently across benchmarks.

The study offers insights into the strengths and limitations of both approaches.

Results inform future choices of optimization techniques in compiler design.

Abstract

Equality saturation has become a dominant paradigm for equational program optimization. However, it has never been rigorously compared to another approach to the same problem, even though several exist, the most notable being stochastic search. In this paper, we compare equality saturation to stochastic search over five benchmarks to answer the question: are e-graphs actually good?