Use valid count returned by inplace_bitmask_and to compute and assign…

… the null count.
rapidsai · Jan 12, 2022 · d1b90f9 · d1b90f9
1 parent 33525d9
commit d1b90f9
Showing 1 changed file with 3 additions and 2 deletions.
diff --git a/cpp/src/structs/utilities.cpp b/cpp/src/structs/utilities.cpp
@@ -322,14 +322,15 @@ void superimpose_parent_nulls(bitmask_type const* parent_null_mask,
       reinterpret_cast<bitmask_type const*>(parent_null_mask),
       reinterpret_cast<bitmask_type const*>(current_child_mask)};
     std::vector<size_type> begin_bits{0, 0};
-    [[maybe_unused]] auto const null_count = cudf::detail::inplace_bitmask_and(
+    auto const valid_count = cudf::detail::inplace_bitmask_and(
       device_span<bitmask_type>(current_child_mask, num_bitmask_words(child.size())),
       masks,
       begin_bits,
       child.size(),
       stream,
       mr);
-    child.set_null_count(UNKNOWN_NULL_COUNT);
+    auto const null_count = child.size() - valid_count;
+    child.set_null_count(null_count);
   }
 
   // If the child is also a struct, repeat for all grandchildren.