Remove is_relationally_comparable for table device views

cpp/include/cudf/table/row_operators.cuh

@@ -355,12 +355,13 @@ class row_lexicographic_comparator {
    * @brief Construct a function object for performing a lexicographic
    * comparison between the rows of two tables.
    *
+   * The caller should ensure the corresponding column types are comparable.
+   *
    * @throws cudf::logic_error if `lhs.num_columns() != rhs.num_columns()`
-   * @throws cudf::logic_error if column types of `lhs` and `rhs` are not comparable.
    *
+   * @param has_nulls Indicates if either input table contains columns with nulls.
    * @param lhs The first table
    * @param rhs The second table (may be the same table as `lhs`)
-   * @param has_nulls Indicates if either input table contains columns with nulls.
    * @param column_order Optional, device array the same length as a row that
    * indicates the desired ascending/descending order of each column in a row.
    * If `nullptr`, it is assumed all columns are sorted in ascending order.
@@ -381,8 +382,6 @@ class row_lexicographic_comparator {
       _null_precedence{null_precedence}
   {
     CUDF_EXPECTS(_lhs.num_columns() == _rhs.num_columns(), "Mismatched number of columns.");
-    CUDF_EXPECTS(detail::is_relationally_comparable(_lhs, _rhs),
-                 "Attempted to compare elements of uncomparable types.");
   }
 
   /**

cpp/include/cudf/table/table_device_view.cuh

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2021, NVIDIA CORPORATION.
+ * Copyright (c) 2019-2022, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -150,10 +150,4 @@ auto contiguous_copy_column_device_views(HostTableView source_view, rmm::cuda_st
   return std::make_tuple(std::move(descendant_storage), d_columns);
 }
 
-namespace detail {
-extern template bool is_relationally_comparable<table_device_view>(table_device_view const& lhs,
-                                                                   table_device_view const& rhs);
-extern template bool is_relationally_comparable<mutable_table_device_view>(
-  mutable_table_device_view const& lhs, mutable_table_device_view const& rhs);
-}  // namespace detail
 }  // namespace cudf

cpp/src/table/table_device_view.cu

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2021, NVIDIA CORPORATION.
+ * Copyright (c) 2019-2022, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -20,8 +20,7 @@
 #include <cudf/utilities/error.hpp>
 
 #include <rmm/cuda_stream_view.hpp>
-
-#include <thrust/logical.h>
+#include <rmm/exec_policy.hpp>
 
 namespace cudf {
 namespace detail {
@@ -54,45 +53,5 @@ template class table_device_view_base<column_device_view, table_view>;
 // Explicit instantiation for a device table of mutable views
 template class table_device_view_base<mutable_column_device_view, mutable_table_view>;
 
-namespace {
-struct is_relationally_comparable_functor {
-  template <typename T>
-  constexpr bool operator()()
-  {
-    return cudf::is_relationally_comparable<T, T>();
-  }
-};
-}  // namespace
-
-template <typename TableView>
-bool is_relationally_comparable(TableView const& lhs, TableView const& rhs)
-{
-  return thrust::all_of(thrust::counting_iterator<size_type>(0),
-                        thrust::counting_iterator<size_type>(lhs.num_columns()),
-                        [lhs, rhs] __device__(auto const i) {
-                          // Simplified this for compile time. (Ideally use double_type_dispatcher)
-                          // TODO: possible to implement without double type dispatcher.
-                          return lhs.column(i).type() == rhs.column(i).type() and
-                                 type_dispatcher(lhs.column(i).type(),
-                                                 is_relationally_comparable_functor{});
-                        });
-}
-
-// Explicit extern template instantiation for a table of immutable views
-extern template bool is_relationally_comparable<table_view>(table_view const& lhs,
-                                                            table_view const& rhs);
-
-// Explicit extern template instantiation for a table of mutable views
-extern template bool is_relationally_comparable<mutable_table_view>(mutable_table_view const& lhs,
-                                                                    mutable_table_view const& rhs);
-
-// Explicit extern template instantiation for a device table of immutable views
-template bool is_relationally_comparable<table_device_view>(table_device_view const& lhs,
-                                                            table_device_view const& rhs);
-
-// Explicit extern template instantiation for a device table of mutable views
-template bool is_relationally_comparable<mutable_table_device_view>(
-  mutable_table_device_view const& lhs, mutable_table_device_view const& rhs);
-
 }  // namespace detail
 }  // namespace cudf

cpp/src/table/table_view.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2019, NVIDIA CORPORATION.
+ * Copyright (c) 2018-2022, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -96,4 +96,36 @@ table_view scatter_columns(table_view const& source,
   return table_view{updated_columns};
 }
 
+namespace detail {
+namespace {
+struct is_relationally_comparable_functor {
+  template <typename T>
+  constexpr bool operator()()
+  {
+    return cudf::is_relationally_comparable<T, T>();
+  }
+};
+}  // namespace
+
+template <typename TableView>
+bool is_relationally_comparable(TableView const& lhs, TableView const& rhs)
+{
+  return std::all_of(thrust::counting_iterator<size_type>(0),
+                     thrust::counting_iterator<size_type>(lhs.num_columns()),
+                     [lhs, rhs](auto const i) {
+                       return lhs.column(i).type() == rhs.column(i).type() and
+                              type_dispatcher(lhs.column(i).type(),
+                                              is_relationally_comparable_functor{});
+                     });
+}
+
+// Explicit extern template instantiation for a table of immutable views
+extern template bool is_relationally_comparable<table_view>(table_view const& lhs,
+                                                            table_view const& rhs);
+
+// Explicit extern template instantiation for a table of mutable views
+extern template bool is_relationally_comparable<mutable_table_view>(mutable_table_view const& lhs,
+                                                                    mutable_table_view const& rhs);
+
+}  // namespace detail
 }  // namespace cudf