Stream: git-wasmtime

Topic: wasmtime / PR #3543 Remove Peepmatic!!!

Wasmtime GitHub notifications bot (Nov 17 2021 at 21:15):

fitzgen opened PR #3543 from remove-peepmatic to main:

Peepmatic was an early attempt at a DSL for peephole optimizations, with the
idea that maybe sometime in the future we could user it for instruction
selection as well. It didn't really pan out, however:

• Peepmatic wasn't quite flexible enough, and adding new operators or snippets
  of code implemented externally in Rust was a bit of a pain.

• The performance was never competitive with the hand-written peephole
  optimizers. It was very size efficient, but that came at the cost of
  run-time efficiency. Everything was table-based and interpreted, rather than
  generating any Rust code.

Ultimately, because of these reasons, we never turned Peepmatic on by default.

These days, we just landed the ISLE domain-specific language, and it is better
suited than Peepmatic for all the things that Peepmatic was originally designed
to do. It is more flexible and easy to integrate with external Rust code. It is
has better time efficiency, meeting or even beating hand-written code. I think a
small part of the reason why ISLE excels in these things is because its design
was informed by Peepmatic's failures. I still plan on continuing Peepmatic's
mission to make Cranelift's peephole optimizer passes generated from DSL rewrite
rules, but using ISLE instead of Peepmatic.

Thank you Peepmatic, rest in peace!

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Wasmtime GitHub notifications bot (Nov 17 2021 at 21:15):

fitzgen requested alexcrichton for a review on PR #3543.

Wasmtime GitHub notifications bot (Nov 17 2021 at 21:48):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Nov 17 2021 at 21:55):

fitzgen merged PR #3543.

Last updated: Nov 22 2024 at 17:03 UTC