Stream: git-wasmtime

Topic: wasmtime / PR #6279 x64: Add non-SSE4.1 lowerings of `pmo...

Wasmtime GitHub notifications bot (Apr 24 2023 at 19:27):

alexcrichton opened PR #6279 from alexcrichton:x64-no-pmovszx to bytecodealliance:main:

This commit adds lowerings for a suite of sign/zero extension instructions which don't require SSE4.1. Like before these lowerings are based on LLVM's output.

This commit also deletes special casees for i16x8.extmul_{low,high}_* since the output of the special case is the same as the default lowering of all the component instructions used within as well.

<!--
Please make sure you include the following information:

• If this work has been discussed elsewhere, please include a link to that
  conversation. If it was discussed in an issue, just mention "issue #...".

• Explain why this change is needed. If the details are in an issue already,
  this can be brief.

Our development process is documented in the Wasmtime book:
https://docs.wasmtime.dev/contributing-development-process.html

Please ensure all communication follows the code of conduct:
https://github.com/bytecodealliance/wasmtime/blob/main/CODE_OF_CONDUCT.md
-->

Wasmtime GitHub notifications bot (Apr 24 2023 at 19:27):

alexcrichton requested abrown for a review on PR #6279.

Wasmtime GitHub notifications bot (Apr 24 2023 at 19:27):

alexcrichton requested wasmtime-compiler-reviewers for a review on PR #6279.

Wasmtime GitHub notifications bot (Apr 26 2023 at 17:42):

abrown submitted PR review.

Wasmtime GitHub notifications bot (Apr 26 2023 at 17:42):

abrown submitted PR review.

Wasmtime GitHub notifications bot (Apr 26 2023 at 17:42):

abrown created PR review comment:

Can't remember all the history of PALIGNR + PMOVZX above but this PUNPCKH might be a better lowering even in the SSE 4.1 case (fewer dependencies?). Just a thought, haven't looked too closely at this...

Wasmtime GitHub notifications bot (Apr 27 2023 at 01:38):

alexcrichton updated PR #6279.

Wasmtime GitHub notifications bot (Apr 27 2023 at 01:39):

alexcrichton created PR review comment:

I believe llvm-mca agrees with you, and LLVM appears to, even when I use the intrinsics for palignr + pmovzx, to still use the pupckh combo with an xor-to-create-zero.

Wasmtime GitHub notifications bot (Apr 27 2023 at 01:43):

alexcrichton has enabled auto merge for PR #6279.

Wasmtime GitHub notifications bot (Apr 27 2023 at 02:54):

alexcrichton merged PR #6279.

Last updated: Dec 23 2024 at 13:07 UTC