_REG_O2
r[_REG_O2] = tf->tf_out[2];
tf->tf_out[2] = r[_REG_O2];
gr[_REG_O2] = tf->tf_out[2];
tf->tf_out[2] = (uint64_t)gr[_REG_O2];
gr[_REG_O2] = tf->tf_out[2];
tf->tf_out[2] = (uint64_t)gr[_REG_O2];