Stream: git-wasmtime

Topic: wasmtime / PR #7465 Cranelift: Fix union node bitpacking

Wasmtime GitHub notifications bot (Nov 02 2023 at 20:11):

fitzgen requested abrown for a review on PR #7465.

Wasmtime GitHub notifications bot (Nov 02 2023 at 20:11):

fitzgen opened PR #7465 from fitzgen:fix-egraph-union to bytecodealliance:main:

It turns out we have just been taking the newest rewrite's value for a eclass union and never actually comparing costs and taking the value with the minimum cost. Whoops!

Fixing this made some test expectations fail, which we resolved by tweaking the cost function to give materializing constants nonzero cost. This way we prefer -x to 0 - x.

We also made elaboration function break ties between values with the same cost with the value index. It prefers larger value indices, since the original value's index will be lower than all of its rewritten values' indices. This heuristically prefers rewritten values because we hope our rewrites are all improvements even when the cost function can't show that.

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Wasmtime GitHub notifications bot (Nov 02 2023 at 20:11):

fitzgen requested wasmtime-compiler-reviewers for a review on PR #7465.

Wasmtime GitHub notifications bot (Nov 02 2023 at 20:14):

cfallin submitted PR review:

LGTM, and thanks for finding this!

Wasmtime GitHub notifications bot (Nov 02 2023 at 20:14):

cfallin has enabled auto merge for PR #7465.

Wasmtime GitHub notifications bot (Nov 03 2023 at 16:06):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 03 2023 at 18:14):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 03 2023 at 21:56):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 03 2023 at 21:58):

fitzgen has enabled auto merge for PR #7465.

Wasmtime GitHub notifications bot (Nov 03 2023 at 22:20):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 03 2023 at 22:20):

fitzgen has disabled auto merge for PR #7465.

Wasmtime GitHub notifications bot (Nov 03 2023 at 22:30):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 06 2023 at 18:07):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 06 2023 at 22:07):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 07 2023 at 17:59):

fitzgen updated PR #7465.

Wasmtime GitHub notifications bot (Nov 07 2023 at 19:37):

fitzgen merged PR #7465.

Last updated: Dec 23 2024 at 12:05 UTC