<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/96950>96950</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Some functions with outlined prologs fail to catch exceptions
        </td>
    </tr>

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

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

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

<pre>
    We have been investigating a bug in an iOS app where a function is failing to catch an exception, leading to a crash. The related functions had their prologs outlined using `-homogeneous-prolog-epilog`, and disabling that optimization fixed the crash. We also found that reverting https://github.com/llvm/llvm-project/commit/6e54fccede402c9ed0e8038aa258a99c5a2773e5 (https://reviews.llvm.org/D153098) also fixed crash when the optimization is enabled.

Since I don't know a lot about CFI instructions, I don't have a small reproducer, but I am happy to provide IR for a few functions if that helps.

@igorkudrin @MaskRay @smeenai Do any of you have some idea of what's going on? Can this diff be safely reverted? Or can we fix somehow?
</pre>
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