n's default operation size is 32 bits. Use of the REX.R prefix permits access to additional registers (R8-R15). Use of the REX.W prefix promotes operation to 64 bits. See the summary chart at the beginning of this section for encoding data and limits.</p>
<h2 id="operation">Operation<a class="anchor" href="#operation">
			¶
		</a></h2>
<pre>TEMP ← SRC
IF ( OperandSize = 16)
    THEN
        DEST[7:0] ← TEMP[15:8];
        DEST[15:8] ← TEMP[7:0];
    ELES IF ( OperandSize = 32)
        DEST[7:0] ← T