ec_field_element_sub
void ec_field_element_sub(const EC_FIELD_MODULUS *m, EC_FIELD_ELEMENT *r,
ec_field_element_sub(&group->fm, &t3, &t3, &t4);
ec_field_element_sub(&group->fm, &t4, &t4, &t5);
ec_field_element_sub(&group->fm, &t5, &t5, &X3);
ec_field_element_sub(&group->fm, &X3, &t1, &Z3);
ec_field_element_sub(&group->fm, &t2, &t0, &t2);
ec_field_element_sub(&group->fm, &X3, &X3, &t0);
ec_field_element_sub(&group->fm, &t3, &t3, &t4);
ec_field_element_sub(&group->fm, &t4, &t4, &X3);
ec_field_element_sub(&group->fm, &Y3, &X3, &Y3);
ec_field_element_sub(&group->fm, &X3, &Y3, &Z3);
ec_field_element_sub(&group->fm, &Z3, &t1, &X3);
ec_field_element_sub(&group->fm, &Y3, &Y3, &t2);
ec_field_element_sub(&group->fm, &Y3, &Y3, &t0);
ec_field_element_sub(&group->fm, &t0, &t0, &t2);
ec_field_element_sub(&group->fm, &X3, &X3, &t1);
ec_field_element_sub(&group->fm, &X3, &t1, &Y3);
ec_field_element_sub(&group->fm, &t3, &t0, &t2);
ec_field_element_sub(&group->fm, &X3, &X3, &t0);
ec_field_element_sub(&group->fm, &Y3, &Y3, &Z3);
ec_field_element_sub(&group->fm, &X3, &t1, &Y3);
ec_field_element_sub(&group->fm, &Z3, &Z3, &t2);
ec_field_element_sub(&group->fm, &Z3, &Z3, &t0);
ec_field_element_sub(&group->fm, &t0, &t0, &t2);
ec_field_element_sub(&group->fm, &X3, &X3, &Z3);
ec_field_element_sub(&group->fm, &y, &group->fm.m, &point->fe_y);