Stream: git-wasmtime

Topic: wasmtime / PR #5097 Cleanup branch and select instructions

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:12):

elliottt opened PR #5097 from trevor/remove-branch-instructions to main:

• Remove br_icmp
• Remove brif
• Remove brff
• Remove trueif/trueff
• Remove selectif
• Refactor selectif_spectre_guard to not use iflags
• Format
• Update tests

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Wasmtime GitHub notifications bot (Oct 21 2022 at 23:14):

elliottt edited PR #5097 from trevor/remove-branch-instructions to main:

As discussed in the 2022/10/19 meeting, this PR removes many of the branch and select instructions that used iflags, in favor if using brz/brnz and select in their place. Additionally, it reworks selectif_spectre_guard to take an i8 input instead of an iflags input.
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Wasmtime GitHub notifications bot (Oct 21 2022 at 23:15):

elliottt edited PR #5097 from trevor/remove-branch-instructions to main:

As discussed in the 2022/10/19 meeting, this PR removes many of the branch and select instructions that used iflags, in favor if using brz/brnz and select in their place. Additionally, it reworks selectif_spectre_guard to take an i8 input instead of an iflags input.
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Wasmtime GitHub notifications bot (Oct 21 2022 at 23:16):

elliottt edited PR #5097 from trevor/remove-branch-instructions to main:

As discussed in the 2022/10/19 meeting, this PR removes many of the branch and select instructions that used iflags, in favor if using brz/brnz and select in their place. Additionally, it reworks selectif_spectre_guard to take an i8 input instead of an iflags input.

For reference, the removed instructions are: br_icmp, brif, brff, trueif, trueff, and selectif.
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Wasmtime GitHub notifications bot (Oct 21 2022 at 23:29):

cfallin submitted PR review.

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:29):

cfallin created PR review comment:

Rather than deleting, can we convert these tests to use icmp / brnz pairs, so we're still testing the proper matching of the two together (and assuring that we don't accidentally materialize the 0/1 value into a register)?

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:29):

cfallin submitted PR review.

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:29):

cfallin created PR review comment:

LIkewise here, switch to icmp/select rather than deleting

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:29):

cfallin created PR review comment:

LIkewise here

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:29):

cfallin created PR review comment:

Likewise here

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:48):

elliottt submitted PR review.

Wasmtime GitHub notifications bot (Oct 21 2022 at 23:48):

elliottt created PR review comment:

Yep, that's a good call!

Wasmtime GitHub notifications bot (Oct 23 2022 at 18:40):

elliottt updated PR #5097 from trevor/remove-branch-instructions to main.

Last updated: Dec 23 2024 at 13:07 UTC