Stream: git-wasmtime

Topic: wasmtime / PR #5895 aarch64: Add support for the `fmls` i...

Wasmtime GitHub notifications bot (Feb 28 2023 at 22:49):

alexcrichton opened PR #5895 from fmls to main:

This commit adds lowerings to the AArch64 backend for the fmls instruction which is intended to be leveraged in the relaxed-simd proposal for WebAssembly. This should hopefully allow for a teeny-bit-more efficient codegen for this operator instead of using the fmla instruction plus a negation instruction.

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Wasmtime GitHub notifications bot (Mar 02 2023 at 02:26):

jameysharp submitted PR review.

Wasmtime GitHub notifications bot (Mar 02 2023 at 02:26):

jameysharp submitted PR review.

Wasmtime GitHub notifications bot (Mar 02 2023 at 02:26):

jameysharp created PR review comment:

I suppose if both x and y are fneg then this can emit fmla instead of fneg+fmls, right? But I guess that's a rewrite we ought to do in the egraph optimizations instead.

Wasmtime GitHub notifications bot (Mar 02 2023 at 05:45):

alexcrichton submitted PR review.

Wasmtime GitHub notifications bot (Mar 02 2023 at 05:45):

alexcrichton created PR review comment:

Indeed! The x64 rules actually end up implementing that (they enable sort of switching back and forth given their structure) but it wasn't as obvious to do here - x64 uses a helper that manages sinking a load as well which adds a fair number of permutations.

I'll send a follow-up which implements the egraph optimization.

Wasmtime GitHub notifications bot (Mar 02 2023 at 06:51):

alexcrichton merged PR #5895.

Last updated: Dec 23 2024 at 12:05 UTC