Stream: git-wasmtime

Topic: wasmtime / PR #2958 x64: fix AVX512 flag checks

Wasmtime GitHub notifications bot (Jun 01 2021 at 18:41):

abrown opened PR #2958 from fix-avx512-flags to main:

Previously, the multiple flags for certain AVX512 instructions were
checked using OR: e.g., if the CPU has AVX512VL OR AVX512DQ,
emit VPMULLQ. This is incorrect--the logic should be AND. The Intel
Software Developer Manual, vol. 1, sec. 15.4, has more information on
this (notable there is the suggestion to check with XGETBV that the OS
is allowing the use of the XMM registers--but that is a separate issue).
This change switches to AND logic in the new backend.

<!--

Please ensure that the following steps are all taken care of before submitting
the PR.

• [ ] This has been discussed in issue #..., or if not, please tell us why
  here.

• [ ] A short description of what this does, why it is needed; if the
  description becomes long, the matter should probably be discussed in an issue
  first.

• [ ] This PR contains test cases, if meaningful.

• [ ] A reviewer from the core maintainer team has been assigned for this PR.
  If you don't know who could review this, please indicate so. The list of
  suggested reviewers on the right can help you.

Please ensure all communication adheres to the code of conduct.
-->

Wasmtime GitHub notifications bot (Jun 01 2021 at 18:41):

abrown requested cfallin for a review on PR #2958.

Wasmtime GitHub notifications bot (Jun 01 2021 at 22:00):

abrown has marked PR #2958 as ready for review.

Wasmtime GitHub notifications bot (Jun 03 2021 at 01:03):

cfallin submitted PR review.

Wasmtime GitHub notifications bot (Jun 03 2021 at 01:03):

cfallin merged PR #2958.

Last updated: Oct 23 2024 at 20:03 UTC