chacha20poly1305: correct AVX2 feature detection

[tmthrgd]

CL 110355 switched out the adhoc cpu feature detection for x/sys/cpu, in
doing so the AVX2 check was broken. The assembly code uses MULX which is
part of BMI2.

Updates golang/go#24843

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Message from Tobias Klauser:

Patch Set 1:

(1 comment)

Thanks.

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Message from Tobias Klauser:

Patch Set 1: Run-TryBot+1

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Patch Set 1:

TryBots beginning. Status page: https://farmer.golang.org/try?commit=f1e186ce

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Patch Set 1:

Build is still in progress...
This change failed on linux-amd64:
See https://storage.googleapis.com/go-build-log/500d79c4/linux-amd64_2d60c2a9.log

Consult https://build.golang.org/ to see whether it's a new failure. Other builds still in progress; subsequent failure notices suppressed until final report.

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Message from Tobias Klauser:

Patch Set 1:

Patch Set 1:

Build is still in progress...
This change failed on linux-amd64:
See https://storage.googleapis.com/go-build-log/500d79c4/linux-amd64_2d60c2a9.log

Consult https://build.golang.org/ to see whether it's a new failure. Other builds still in progress; subsequent failure notices suppressed until final report.

TryBot failure is unrelated, see https://golang.org/issue/25199

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Message from Tom Thorogood:

Patch Set 1:

Patch Set 1:

Build is still in progress...
This change failed on linux-amd64:
See https://storage.googleapis.com/go-build-log/500d79c4/linux-amd64_2d60c2a9.log

Consult https://build.golang.org/ to see whether it's a new failure. Other builds still in progress; subsequent failure notices suppressed until final report.

This is just golang/go#25199 right?

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Message from Tom Thorogood:

Patch Set 2: Commit message was updated.

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Message from Gobot Gobot:

Patch Set 1: TryBot-Result-1

6 of 6 TryBots failed:
Failed on linux-amd64: https://storage.googleapis.com/go-build-log/500d79c4/linux-amd64_2d60c2a9.log
Failed on linux-386: https://storage.googleapis.com/go-build-log/500d79c4/linux-386_6784d523.log
Failed on freebsd-amd64-11_1: https://storage.googleapis.com/go-build-log/500d79c4/freebsd-amd64-11_1_891a49f3.log
Failed on openbsd-amd64-62: https://storage.googleapis.com/go-build-log/500d79c4/openbsd-amd64-62_a3597b40.log
Failed on windows-amd64-2016: https://storage.googleapis.com/go-build-log/500d79c4/windows-amd64-2016_4a1650bc.log
Failed on windows-386-2008: https://storage.googleapis.com/go-build-log/500d79c4/windows-386-2008_3b76a36b.log

Consult https://build.golang.org/ to see whether they are new failures.

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Uploaded patch set 3: Commit message was updated.

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This PR (HEAD: 70542b5) has been imported to Gerrit for code review.

Please visit https://go-review.googlesource.com/#/c/crypto/+/110796 to see it.

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Uploaded patch set 4: Commit message was updated.

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Message from Gerrit Bot:

Uploaded patch set 5: Commit message was updated.

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Message from Tom Thorogood:

Patch Set 5:

(1 comment)

Sorry for my fighting with Gerritbot there.

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Message from Tobias Klauser:

Patch Set 5:

Patch Set 1:

Patch Set 1:

Build is still in progress...
This change failed on linux-amd64:
See https://storage.googleapis.com/go-build-log/500d79c4/linux-amd64_2d60c2a9.log

Consult https://build.golang.org/ to see whether it's a new failure. Other builds still in progress; subsequent failure notices suppressed until final report.

This is just golang/go#25199 right?

Yes, looks like it.

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Message from Tobias Klauser:

Patch Set 5: Code-Review+2

Patch Set 5:

(1 comment)

Sorry for my fighting with Gerritbot there.

No problem, thanks for the update.

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This PR is being closed because golang.org/cl/110796 has been merged.