another version of fillRowAddMatrix() for factorization, but still slower
another version of fillRowAddMatrix() for factorization, but still slower

mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs