remove unnecessary sorting

cpp/src/community/k_truss_impl.cuh

@@ -176,13 +176,13 @@ edge_t remove_overcompensating_edges(raft::handle_t const& handle,
 }
 
 template <typename vertex_t, typename edge_t, bool multi_gpu, bool is_q_r_edge>
-void find_unroll_p_r_or_q_r_edges(
+void unroll_p_r_or_q_r_edges(
   raft::handle_t const& handle,
   graph_view_t<vertex_t, edge_t, false, false>& graph_view,
   edge_t num_invalid_edges,
   edge_t num_valid_edges,
-  raft::device_span<vertex_t> edgelist_srcs,  // FIXME: Use device_span instead
-  raft::device_span<vertex_t> edgelist_dsts,
+  raft::device_span<vertex_t const> edgelist_srcs,
+  raft::device_span<vertex_t const> edgelist_dsts,
   raft::device_span<edge_t> num_triangles)
 {
   auto prefix_sum_valid = prefix_sum_valid_and_invalid_edges(
@@ -823,38 +823,24 @@ std::tuple<rmm::device_uvector<vertex_t>, rmm::device_uvector<vertex_t>> k_truss
       // case 2: unroll (q, r)
       // For each (q, r) edges to unroll, find the incoming edges to 'r' let's say from 'p' and
       // create the pair (p, q)
-      cugraph::find_unroll_p_r_or_q_r_edges<vertex_t, edge_t, false, true>(
+      cugraph::unroll_p_r_or_q_r_edges<vertex_t, edge_t, false, true>(
         handle,
         cur_graph_view,
         num_invalid_edges,
         num_valid_edges,
-        raft::device_span<vertex_t>(edgelist_srcs.data(), edgelist_srcs.size()),
-        raft::device_span<vertex_t>(edgelist_dsts.data(), edgelist_dsts.size()),
+        raft::device_span<vertex_t const>(edgelist_srcs.data(), edgelist_srcs.size()),
+        raft::device_span<vertex_t const>(edgelist_dsts.data(), edgelist_dsts.size()),
         raft::device_span<edge_t>(num_triangles.data(), num_triangles.size()));
 
       // case 3: unroll (p, r)
-      cugraph::find_unroll_p_r_or_q_r_edges<vertex_t, edge_t, false, false>(
+      cugraph::unroll_p_r_or_q_r_edges<vertex_t, edge_t, false, false>(
         handle,
         cur_graph_view,
         num_invalid_edges,
         num_valid_edges,
-        raft::device_span<vertex_t>(edgelist_srcs.data(), edgelist_srcs.size()),
-        raft::device_span<vertex_t>(edgelist_dsts.data(), edgelist_dsts.size()),
+        raft::device_span<vertex_t const>(edgelist_srcs.data(), edgelist_srcs.size()),
+        raft::device_span<vertex_t const>(edgelist_dsts.data(), edgelist_dsts.size()),
         raft::device_span<edge_t>(num_triangles.data(), num_triangles.size()));
-
-      auto edges_with_triangle_last =
-        thrust::stable_partition(handle.get_thrust_policy(),
-                                 transposed_edge_triangle_count_pair_first,
-                                 transposed_edge_triangle_count_pair_first + num_triangles.size(),
-                                 [] __device__(auto e) {
-                                   auto num_triangles = thrust::get<1>(e);
-                                   return num_triangles > 0;
-                                 });
-
-
-
-      size_t num_edges_with_triangles = static_cast<size_t>(
-        thrust::distance(transposed_edge_triangle_count_pair_first, edges_with_triangle_last));
 
       //cugraph::edge_property_t<decltype(cur_graph_view), bool> edge_mask(handle, cur_graph_view);
       // Set edge property to 'True' for all edges then mask out invalid edges which can be
@@ -870,8 +856,6 @@ std::tuple<rmm::device_uvector<vertex_t>, rmm::device_uvector<vertex_t>> k_truss
                                     edgelist_srcs.end(),
                                     edgelist_dsts.begin() + num_edges_with_triangles);
 
-      // FIXME: Cannot modify an edgemask that is still attached.
-      // This can lead to race conditions
       cur_graph_view.clear_edge_mask();
       cugraph::transform_e(
         handle,