<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/55213>55213</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            clang 15.0.0 causes regression on O3 optimisation compared to clang 14.0
        </td>
    </tr>

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

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

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

<pre>
    here is a test case where clang 14 optimises better than clang trunk (15.0.0)
https://godbolt.org/z/j9zhcrjdz

this happens even when the lookup table is constant and local 
https://godbolt.org/z/61hvEP4Y9

according to https://godbolt.org/z/GWGKsed1f
it seems clang trunk in compiler explorer points to this exact commit
https://github.com/llvm/llvm-project/commit/09325d36061e42b495d1f4c7e933e260eac260ed

</pre>
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