as determined by the internal value XRSTOR_INFO (see the Operation section below).</li>
<li>XSAVEOPT does not modify bytes 511:464 of the legacy region of the XSAVE area (see Section 13.4.1, “Legacy Region of an XSAVE Area”).</li>
<li>XSAVEOPT reads the XSTATE_BV field of the XSAVE header (see Section 13.4.2, “XSAVE Header”) and writes a modified value back to memory as follows. If RFBM[<em>i</em>] = 1, XSAVEOPT writes XSTATE_BV[<em>i</em>] with the value of XINUSE[<em>i</em>]. If RFBM[<em>i</em>] =