fprsqrta 操作 字型慣例
if (PR[qp]) {
fp_check_target_register;
if (tmp_isrcode = fp_reg_disabled(f1, f3, 0, 0))
disabled_fp_register_fault(tmp_isrcode, 0);

if (fp_is_natval(FR[f3])) {
FR[f1] = NATVAL;
PR[p2] = 0;
} else {
tmp_default_result_pair = fprsqrta_exception_fault_check(f3, sf,
&tmp_fp_env, &limits_check);
if (fp_raise_fault(tmp_fp_env))
fp_exception_fault(fp_decode_fault(tmp_fp_env));

if (fp_is_nan(tmp_default_result_pair.hi)) {
tmp_res_hi = fp_single(tmp_default_result_pair.hi);
tmp_pred_hi = 0;
} else {
tmp_fr3 = fp_normalize(fp_reg_read_hi(f3));
if (fp_is_zero(tmp_fr3)) {
tmp_res = FP_INFINITY;
tmp_res.sign = tmp_fr3.sign;
tmp_pred_hi = 0;
} else if (fp_is_pos_inf(tmp_fr3)) {
tmp_res = FP_ZERO;
tmp_pred_hi = 0;
} else {
tmp_res = fp_ieee_recip_sqrt(tmp_fr3);
if (limits_check.hi)
tmp_pred_hi = 0;
else
tmp_pred_hi = 1;
}
tmp_res_hi = fp_single(tmp_res);
}

if (fp_is_nan(tmp_default_result_pair.lo)) {
tmp_res_lo = fp_single(tmp_default_result_pair.lo);
tmp_pred_lo = 0;
} else {
tmp_fr3 = fp_normalize(fp_reg_read_lo(f3));
if (fp_is_zero(tmp_fr3)) {
tmp_res = FP_INFINITY;
tmp_res.sign = tmp_fr3.sign;
tmp_pred_lo = 0;
} else if (fp_is_pos_inf(tmp_fr3)) {
tmp_res = FP_ZERO;
tmp_pred_lo = 0;
} else {
tmp_res = fp_ieee_recip_sqrt(tmp_fr3);
if (limits_check.lo)
tmp_pred_lo = 0;
else
tmp_pred_lo = 1;
}
tmp_res_lo = fp_single(tmp_res);
}

FR[f1].significand = fp_concatenate(tmp_res_hi, tmp_res_lo);
FR[f1].exponent = FP_INTEGER_EXP;
FR[f1].sign = FP_SIGN_POSITIVE;
PR[p2] = tmp_pred_hi && tmp_pred_lo;

fp_update_fpsr(sf, tmp_fp_env);
}
fp_update_psr(f1);
} else {
PR[p2] = 0;
}