gf_div
coeff[MUL_QR_X] = gf_div(ny, d);
coeff[MUL_QR_Y] = gf_div(nx, d);
coeff[MUL_PQR_XP] = gf_div(nyyz ^ nyzz, xd);
coeff[MUL_PQR_XQ] = gf_div(nyy ^ nzz, xd);
coeff[MUL_PQR_XR] = gf_div(ny ^ nz, xd);
coeff[MUL_PQ_X] = gf_div(a, e);
coeff[MUL_PQ_Y] = gf_div(b, e);
coeff[MUL_PR_X] = gf_div(a, e);
coeff[MUL_PR_Y] = gf_div(b, e);