<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/122681>122681</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            RISC-V EVL tail folding failure on SPEC CPU 2017 525.x264_r
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            backend:RISC-V,
            vectorizers
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          lukel97
      </td>
    </tr>
</table>

<pre>
    Split out from the discussion here: https://github.com/llvm/llvm-project/pull/122458#issuecomment-2585713670 

On RISC-V with `-march=rva22u64_v -O3 -flto -mllvm -force-tail-folding-style=data-with-evl -mllvm -prefer-predicate-over-epilogue=predicate-else-scalar-epilogue`, the SPEC CPU 2017 525.x264_r benchmark fails in the train dataset, likely due to a miscompile.

It's been failing since at least 6ad0dcf67f5dccdf8506ce5f51d793062a1c6879, detected from this LNT run: https://lnt.lukelau.me/db_default/v4/nts/89
</pre>
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