Refactor cudf::contains (NVIDIA#10997)

This is just a simple refactor to `cudf::contains`:
 * Remove `cudf/structs/detail/contains.hpp` and its corrresponding source file `src/structs/search/contains.cu`, moving its (modified) implementation into `src/search/contains_nested.cu`.
 * Adopt `experimental::row::equality::two_table_comparator` for struct equality comparison.
 * Add `const` qualifier for the `operator()` functions.
 * Rename some variables, and reorganize code to make it cleaner.

No new feature is added in this PR, just modifying the existing functions and moving things around.

This PR is extracted from the bigger PR for easier review. The original PR is rapidsai/cudf#10656 for fully supporting nested type in `cudf::contains`. As such, this blocks it.

Authors:
  - Nghia Truong (https://github.com/ttnghia)
  - Devavret Makkar (https://github.com/devavret)
  - Bradley Dice (https://github.com/bdice)

Approvers:
  - David Wendt (https://github.com/davidwendt)
  - Jordan Jacobelli (https://github.com/Ethyling)
  - Robert Maynard (https://github.com/robertmaynard)
  - Yunsong Wang (https://github.com/PointKernel)

URL: rapidsai/cudf#10997

conda/recipes/libcudf/meta.yaml

@@ -247,7 +247,6 @@ outputs:
         - test -f $PREFIX/include/cudf/structs/structs_column_view.hpp
         - test -f $PREFIX/include/cudf/structs/struct_view.hpp
         - test -f $PREFIX/include/cudf/structs/detail/concatenate.hpp
-        - test -f $PREFIX/include/cudf/structs/detail/contains.hpp
         - test -f $PREFIX/include/cudf/table/table.hpp
         - test -f $PREFIX/include/cudf/table/table_view.hpp
         - test -f $PREFIX/include/cudf/tdigest/tdigest_column_view.cuh

cpp/CMakeLists.txt

@@ -446,6 +446,7 @@ add_library(
   src/scalar/scalar.cpp
   src/scalar/scalar_factories.cpp
   src/search/contains.cu
+  src/search/contains_nested.cu
   src/search/search_ordered.cu
   src/sort/is_sorted.cu
   src/sort/rank.cu
@@ -514,7 +515,6 @@ add_library(
   src/strings/utilities.cu
   src/strings/wrap.cu
   src/structs/copying/concatenate.cu
-  src/structs/search/contains.cu
   src/structs/structs_column_factories.cu
   src/structs/structs_column_view.cpp
   src/structs/utilities.cpp

cpp/include/cudf/detail/search.hpp

@@ -23,35 +23,30 @@
 
 #include <rmm/cuda_stream_view.hpp>
 
-#include <vector>
-
-namespace cudf {
-namespace detail {
+namespace cudf::detail {
 /**
  * @copydoc cudf::lower_bound
  *
  * @param stream CUDA stream used for device memory operations and kernel launches.
  */
-std::unique_ptr<column> lower_bound(
-  table_view const& haystack,
-  table_view const& needles,
-  std::vector<order> const& column_order,
-  std::vector<null_order> const& null_precedence,
-  rmm::cuda_stream_view stream,
-  rmm::mr::device_memory_resource* mr = rmm::mr::get_current_device_resource());
+std::unique_ptr<column> lower_bound(table_view const& haystack,
+                                    table_view const& needles,
+                                    std::vector<order> const& column_order,
+                                    std::vector<null_order> const& null_precedence,
+                                    rmm::cuda_stream_view stream,
+                                    rmm::mr::device_memory_resource* mr);
 
 /**
  * @copydoc cudf::upper_bound
  *
  * @param stream CUDA stream used for device memory operations and kernel launches.
  */
-std::unique_ptr<column> upper_bound(
-  table_view const& haystack,
-  table_view const& needles,
-  std::vector<order> const& column_order,
-  std::vector<null_order> const& null_precedence,
-  rmm::cuda_stream_view stream,
-  rmm::mr::device_memory_resource* mr = rmm::mr::get_current_device_resource());
+std::unique_ptr<column> upper_bound(table_view const& haystack,
+                                    table_view const& needles,
+                                    std::vector<order> const& column_order,
+                                    std::vector<null_order> const& null_precedence,
+                                    rmm::cuda_stream_view stream,
+                                    rmm::mr::device_memory_resource* mr);
 
 /**
  * @copydoc cudf::contains(column_view const&, scalar const&, rmm::mr::device_memory_resource*)
@@ -65,11 +60,25 @@ bool contains(column_view const& haystack, scalar const& needle, rmm::cuda_strea
  *
  * @param stream CUDA stream used for device memory operations and kernel launches.
  */
-std::unique_ptr<column> contains(
-  column_view const& haystack,
-  column_view const& needles,
-  rmm::cuda_stream_view stream,
-  rmm::mr::device_memory_resource* mr = rmm::mr::get_current_device_resource());
+std::unique_ptr<column> contains(column_view const& haystack,
+                                 column_view const& needles,
+                                 rmm::cuda_stream_view stream,
+                                 rmm::mr::device_memory_resource* mr);
+
+/**
+ * @brief Check if the (unique) row of the `needle` column is contained in the `haystack` column.
+ *
+ * If the input `needle` column has more than one row, only the first row will be considered.
+ *
+ * This function is designed for nested types only. It can also work with non-nested types
+ * but with lower performance due to the complexity of the implementation.
+ *
+ * @param haystack The column containing search space.
+ * @param needle A scalar value to check for existence in the search space.
+ * @return true if the given `needle` value exists in the `haystack` column.
+ */
+bool contains_nested_element(column_view const& haystack,
+                             column_view const& needle,
+                             rmm::cuda_stream_view stream);
 
-}  // namespace detail
-}  // namespace cudf
+}  // namespace cudf::detail

cpp/src/hash/unordered_multiset.cuh

@@ -131,7 +131,7 @@ class unordered_multiset {
     return unordered_multiset(d_col.size(), std::move(hash_bins_start), std::move(hash_data));
   }
 
-  unordered_multiset_device_view<Element, Hasher, Equality> to_device()
+  unordered_multiset_device_view<Element, Hasher, Equality> to_device() const
   {
     return unordered_multiset_device_view<Element, Hasher, Equality>(
       size, hash_bins.data(), hash_data.data());