Fix some libcudf functions to set the null count on returning columns (…

…#13331)

Fixes a few more places where the null count was not being set in a libcudf function before returning a column. A couple of places were setting the null count value into the mutable-view object. So the value was calculated correctly but not set into the actual column object.

Reference: #11968

Authors:
  - David Wendt (https://github.com/davidwendt)

Approvers:
  - Vyas Ramasubramani (https://github.com/vyasr)
  - Nghia Truong (https://github.com/ttnghia)

URL: #13331

cpp/src/binaryop/binaryop.cpp

@@ -217,6 +217,8 @@ std::unique_ptr<column> binary_operation(LhsType const& lhs,
 
   auto out_view = out->mutable_view();
   cudf::binops::compiled::binary_operation(out_view, lhs, rhs, op, stream);
+  // TODO: consider having the binary_operation count nulls instead
+  out->set_null_count(cudf::detail::null_count(out_view.null_mask(), 0, out->size(), stream));
   return out;
 }
 }  // namespace compiled
@@ -373,6 +375,7 @@ std::unique_ptr<column> binary_operation(column_view const& lhs,
 
   auto out_view = out->mutable_view();
   binops::jit::binary_operation(out_view, lhs, rhs, ptx, stream);
+  out->set_null_count(cudf::detail::null_count(out_view.null_mask(), 0, out->size(), stream));
   return out;
 }
 }  // namespace detail

cpp/src/copying/copy_range.cu

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2022, NVIDIA CORPORATION.
+ * Copyright (c) 2019-2023, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -108,6 +108,7 @@ struct out_of_place_copy_range_dispatch {
     if (source_end != source_begin) {  // otherwise no-op
       auto ret_view = p_ret->mutable_view();
       in_place_copy_range<T>(source, ret_view, source_begin, source_end, target_begin, stream);
+      p_ret->set_null_count(ret_view.null_count());
     }
 
     return p_ret;

cpp/src/filling/fill.cu

@@ -122,6 +122,7 @@ struct out_of_place_fill_range_dispatch {
       auto ret_view    = p_ret->mutable_view();
       using DeviceType = cudf::device_storage_type_t<T>;
       in_place_fill<DeviceType>(ret_view, begin, end, value, stream);
+      p_ret->set_null_count(ret_view.null_count());
     }
 
     return p_ret;

cpp/tests/copying/purge_nonempty_nulls_tests.cpp

@@ -75,6 +75,7 @@ TEST_F(PurgeNonEmptyNullsTest, SingleLevelList)
   // Set nullmask, post construction.
   cudf::detail::set_null_mask(
     input->mutable_view().null_mask(), 2, 3, false, cudf::get_default_stream());
+  input->set_null_count(1);
   EXPECT_TRUE(cudf::may_have_nonempty_nulls(*input));
   EXPECT_TRUE(cudf::has_nonempty_nulls(*input));
 
@@ -158,6 +159,7 @@ TEST_F(PurgeNonEmptyNullsTest, TwoLevelList)
   // Set nullmask, post construction.
   cudf::detail::set_null_mask(
     input->mutable_view().null_mask(), 3, 4, false, cudf::get_default_stream());
+  input->set_null_count(1);
   EXPECT_TRUE(cudf::may_have_nonempty_nulls(*input));
   EXPECT_TRUE(cudf::has_nonempty_nulls(*input));
 
@@ -213,6 +215,7 @@ TEST_F(PurgeNonEmptyNullsTest, ThreeLevelList)
   // Set nullmask, post construction.
   cudf::detail::set_null_mask(
     input->mutable_view().null_mask(), 3, 4, false, cudf::get_default_stream());
+  input->set_null_count(1);
   EXPECT_TRUE(cudf::may_have_nonempty_nulls(*input));
   EXPECT_TRUE(cudf::has_nonempty_nulls(*input));
 
@@ -267,6 +270,7 @@ TEST_F(PurgeNonEmptyNullsTest, ListOfStrings)
   // Set nullmask, post construction.
   cudf::detail::set_null_mask(
     input->mutable_view().null_mask(), 2, 3, false, cudf::get_default_stream());
+  input->set_null_count(1);
   EXPECT_TRUE(cudf::may_have_nonempty_nulls(*input));
   EXPECT_TRUE(cudf::has_nonempty_nulls(*input));
 
@@ -332,6 +336,7 @@ TEST_F(PurgeNonEmptyNullsTest, UnsanitizedListOfUnsanitizedStrings)
 
   // Set strings nullmask, post construction.
   cudf::set_null_mask(strings->mutable_view().null_mask(), 7, 8, false);
+  strings->set_null_count(1);
   EXPECT_TRUE(cudf::may_have_nonempty_nulls(*strings));
   EXPECT_TRUE(cudf::has_nonempty_nulls(*strings));
 
@@ -358,6 +363,7 @@ TEST_F(PurgeNonEmptyNullsTest, UnsanitizedListOfUnsanitizedStrings)
   // Set lists nullmask, post construction.
   cudf::detail::set_null_mask(
     lists->mutable_view().null_mask(), 2, 3, false, cudf::get_default_stream());
+  lists->set_null_count(1);
   EXPECT_TRUE(cudf::may_have_nonempty_nulls(*lists));
   EXPECT_TRUE(cudf::has_nonempty_nulls(*lists));