<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/110159>110159</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            BPF backend adding unnecessary bitmasks after loads
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          brycekahle
      </td>
    </tr>
</table>

<pre>
    The BPF backend seems to be adding bitmasks (`&= 255` in this case, for `u8`) after loads, even though we get zero extension for free from loads.

See line 9 of the output for 18.1.0 in https://godbolt.org/z/K5M6MhWxs

I `git bisect`ed the introduction of the problem to this commit: https://github.com/llvm/llvm-project/commit/651e644595b72c22fd22f51358cf083146790ed4

@eddyz87 
</pre>
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