d></tr>
<tr>
<td>#AC(0)</td>
<td>If alignment checking is enabled and an unaligned memory reference is made while the current privilege level is 3.</td></tr>
<tr>
<td rowspan="4">#UD</td>
<td>If CPUID.01H:ECX.MOVBE[bit 22] = 0.</td></tr>
<tr>
<td>If the LOCK prefix is used.</td></tr>
<tr>
<td>If REP (F3H) prefix is used.</td></tr>
<tr>
<td>If REPNE (F2H) prefix is used and CPUID.01H:ECX.SSE4_2[bit 20] = 0.</td></tr></table>
<h2 class="exceptions" id="compatibility-mode-exceptions">Compatibility Mode Excepti