FSR_NV
fe->fe_cx = FSR_NV;
fe->fe_cx = FSR_NV; /* assert invalid operand */
fe->fe_cx = (fe->fe_cx & ~FSR_NX) | FSR_NV;
fe->fe_cx = (fe->fe_cx & ~FSR_NX) | FSR_NV;
fe->fe_cx = FSR_NV;