[cfallin]

We actually take a fairly unconventional approach to e-graphs: we have a few linear passes and we do all rewrites eagerly, so we use them to provide a general framework for the fixpoint problem into which we plug in all our rewrites, but we don't have the usual "apply as much CPU time as you want to get better results" property of conventional equality saturation.

I gave a talk about this approach, aegraphs (acyclic e-graphs), here: slides (https://cfallin.org/pubs/egraphs2023_aegraphs_slides.pdf), video (https://vimeo.com/843540328)

(disclosure: Cranelift tech lead 2020-2022 and main author of the e-graphs mid-end, as well as regalloc, isel and its custom DSL, and other bits, along with the excellent team)

[scoopr]

I found the video to be great! Informative and understandable even when I'm just casually interested in compilers, with not a lot of real world experience writing them.