<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/128062>128062</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Unprofitable loop vectorization
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            vectorizers,
            missed-optimization
      </td>
    </tr>

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

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

<pre>
    LoopVectorize generates something really bad here, with lots of element-wise loads, inserts, extracts and stores. Letting it fall through to SLP generates much better code.

LoopVectorize: https://llvm.godbolt.org/z/dPcEedY1v
SLPVectorizer: https://llvm.godbolt.org/z/33d31djno
</pre>
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