lshiftl
div = lshiftl(div, 1);
lop = lshiftl(lop, 1);
ans = lshiftl(ans, 1);
if ((lshiftl(rop, -jj).dl_lop & 1) == 0)
tmp = lshiftl(lop, jj);
extern dl_t lshiftl(dl_t, int);