Fix test regression

[rebornix]

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• Commit message has a short title & issue references
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As title. Since we still have test failure in local (those god name ones), sometimes we fail to realize our code change brings more failure.

[rebornix]

The first build job passed while the second said 1) register Can use two registers together: ... failed.

[jpoon]

I restarted the failed build job. We'll see if that helps.

Update: nope, legit error.

[johnfn]

Hmm, looks like it may be a real be unrelated bug on OSX. In any case, it's not related to this PR, which is fine. Thanks @rebornix!