Address primitives performance regression with the added edge masking…

… support (when edge masking is not in use) (#4119)

This addresses performance regression due to the added edge masking support when edge masking is disabled.

We addressed the issue for `per_v_transform_reduce_incoming|outgoing_e` in #4085

Using a similar approach, we address the issue for `transform_e`, `transform_reduce_e`, and `detail::nbr_intersection` in this PR.

Authors:
  - Seunghwa Kang (https://github.com/seunghwak)

Approvers:
  - Chuck Hastings (https://github.com/ChuckHastings)
  - Naim (https://github.com/naimnv)

URL: #4119

cpp/src/prims/detail/nbr_intersection.cuh

@@ -319,7 +319,8 @@ struct pick_min_degree_t {
   }
 };
 
-template <typename InputKeyIterator0,
+template <bool check_edge_mask,
+          typename InputKeyIterator0,
           typename InputKeyIterator1,
           typename InputValueIterator0,  // should be void* if invalid
           typename InputValueIterator1,  // should be void* if invalid
@@ -356,10 +357,14 @@ __device__ edge_t set_intersection_by_key_with_mask(InputKeyIterator0 input_key_
   auto output_idx = output_start_offset;
   while ((idx0 < (input_start_offset0 + input_size0)) &&
          (idx1 < (input_start_offset1 + input_size1))) {
-    bool valid0 = apply_mask0 ? check_bit_set(idx0) : true;
-    bool valid1 = apply_mask1 ? check_bit_set(idx1) : true;
-    if (!valid0) { ++idx0; }
-    if (!valid1) { ++idx1; }
+    bool valid0 = true;
+    bool valid1 = true;
+    if constexpr (check_edge_mask) {
+      valid0 = apply_mask0 ? check_bit_set(idx0) : true;
+      valid1 = apply_mask1 ? check_bit_set(idx1) : true;
+      if (!valid0) { ++idx0; }
+      if (!valid1) { ++idx1; }
+    }
 
     if (valid0 && valid1) {
       auto key0 = *(input_key_first0 + idx0);
@@ -522,24 +527,42 @@ struct copy_intersecting_nbrs_and_update_intersection_size_t {
     // vertices in a single warp (better optimize if this becomes a performance
     // bottleneck)
 
-    auto mask_first        = edge_partition_e_mask ? (*edge_partition_e_mask).value_first()
-                                                   : static_cast<uint32_t const*>(nullptr);
-    auto intersection_size = set_intersection_by_key_with_mask(
-      indices0,
-      indices1,
-      edge_property_values0,
-      edge_property_values1,
-      mask_first,
-      nbr_intersection_indices.begin(),
-      nbr_intersection_e_property_values0,
-      nbr_intersection_e_property_values1,
-      local_edge_offset0,
-      local_degree0,
-      (std::is_same_v<FirstElementToIdxMap, void*> && edge_partition_e_mask),
-      local_edge_offset1,
-      local_degree1,
-      (std::is_same_v<SecondElementToIdxMap, void*> && edge_partition_e_mask),
-      nbr_intersection_offsets[i]);
+    edge_t intersection_size{};
+    if (edge_partition_e_mask) {
+      intersection_size =
+        set_intersection_by_key_with_mask<true>(indices0,
+                                                indices1,
+                                                edge_property_values0,
+                                                edge_property_values1,
+                                                (*edge_partition_e_mask).value_first(),
+                                                nbr_intersection_indices.begin(),
+                                                nbr_intersection_e_property_values0,
+                                                nbr_intersection_e_property_values1,
+                                                local_edge_offset0,
+                                                local_degree0,
+                                                std::is_same_v<FirstElementToIdxMap, void*>,
+                                                local_edge_offset1,
+                                                local_degree1,
+                                                std::is_same_v<SecondElementToIdxMap, void*>,
+                                                nbr_intersection_offsets[i]);
+    } else {
+      intersection_size =
+        set_intersection_by_key_with_mask<false>(indices0,
+                                                 indices1,
+                                                 edge_property_values0,
+                                                 edge_property_values1,
+                                                 static_cast<uint32_t const*>(nullptr),
+                                                 nbr_intersection_indices.begin(),
+                                                 nbr_intersection_e_property_values0,
+                                                 nbr_intersection_e_property_values1,
+                                                 local_edge_offset0,
+                                                 local_degree0,
+                                                 false,
+                                                 local_edge_offset1,
+                                                 local_degree1,
+                                                 false,
+                                                 nbr_intersection_offsets[i]);
+    }
 
     thrust::fill(
       thrust::seq,
@@ -714,7 +737,7 @@ nbr_intersection(raft::handle_t const& handle,
   auto edge_mask_view = graph_view.edge_mask_view();
 
   std::optional<std::unique_ptr<kv_store_t<vertex_t, vertex_t, false>>> major_to_idx_map_ptr{
-    std::nullopt};
+    std::nullopt};  // idx to major_nbr_offsets
   std::optional<rmm::device_uvector<edge_t>> major_nbr_offsets{std::nullopt};
   std::optional<rmm::device_uvector<vertex_t>> major_nbr_indices{std::nullopt};
 
@@ -1041,7 +1064,7 @@ nbr_intersection(raft::handle_t const& handle,
   // 3. Collect neighbor list for minors (for the neighbors within the minor range for this GPU)
 
   std::optional<std::unique_ptr<kv_store_t<vertex_t, vertex_t, false>>> minor_to_idx_map_ptr{
-    std::nullopt};
+    std::nullopt};  // idx to minor_nbr_offsets
   std::optional<rmm::device_uvector<size_t>> minor_nbr_offsets{std::nullopt};
   std::optional<rmm::device_uvector<vertex_t>> minor_nbr_indices{std::nullopt};