<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/106209>106209</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [M68k] M68kExpandPseudo::ExpandMI and M68kInstrInfo::ExpandMOVEM incorrectly promote 8bit and 16bit registers to 32bit
        </td>
    </tr>

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

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

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

<pre>
    The functions `M68kExpandPseudo::ExpandMI` and `M68kInstrInfo::ExpandMOVEM` unconditionally promote MOVEM instructions to their 32bit variant to allow collapsing multiple consecutive instructions. This optimisation, however, clashes with the representation of these values in memory. For instance, a 16bit value will still only be allocated 2 bytes on the stack, causing unrelated data to be overwritten when the 32bit MOVEM is executed.
</pre>
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