fclass 操作 字型慣例
if (PR[qp]) {
if (p1 == p2)
illegal_operation_fault();

if (tmp_isrcode = fp_reg_disabled(f2, 0, 0, 0))
disabled_fp_register_fault(tmp_isrcode, 0);

tmp_rel = ( (fclass9{0} && ![f2].sign || fclass9{1} && FR[f2].sign)
&& ((fclass9{2} && fp_is_zero(FR[f2]))||
(fclass9{3} && fp_is_unorm(FR[f2])) ||
(fclass9{4} && fp_is_normal(FR[f2])) ||
(fclass9{5} && fp_is_inf(FR[f2]))
)
)
|| (fclass9{6} && fp_is_snan(FR[f2]))
|| (fclass9{7} && fp_is_qnan(FR[f2]))
|| (fclass9{8} && fp_is_natval(FR[f2]));

tmp_nat = fp_is_natval(FR[f2]) && (!fclass9{8});

if (tmp_nat) {
PR[p1] = 0;
PR[p2] = 0;
} else {
PR[p1] = tmp_rel;
PR[p2] = !tmp_rel;
}
} else {
if (fctype == ‘unc') {
if (p1 == p2)
illegal_operation_fault();
PR[p1] = 0;
PR[p2] = 0;
}
}