Use std::optional for host types (#17015)

cuda::std::optional shouldn't be used for host types such as `std::vector` as it requires the constructors of the `T` types to be host+device.

Authors:
  - Robert Maynard (https://github.com/robertmaynard)

Approvers:
  - Bradley Dice (https://github.com/bdice)
  - MithunR (https://github.com/mythrocks)
  - Nghia Truong (https://github.com/ttnghia)

URL: #17015

cpp/src/io/parquet/compact_protocol_reader.cpp

@@ -309,10 +309,10 @@ class parquet_field_struct : public parquet_field {
 template <typename E, typename T>
 class parquet_field_union_struct : public parquet_field {
   E& enum_val;
-  cuda::std::optional<T>& val;  // union structs are always wrapped in std::optional
+  std::optional<T>& val;  // union structs are always wrapped in std::optional
 
  public:
-  parquet_field_union_struct(int f, E& ev, cuda::std::optional<T>& v)
+  parquet_field_union_struct(int f, E& ev, std::optional<T>& v)
     : parquet_field(f), enum_val(ev), val(v)
   {
   }
@@ -439,10 +439,10 @@ class parquet_field_struct_blob : public parquet_field {
  */
 template <typename T, typename FieldFunctor>
 class parquet_field_optional : public parquet_field {
-  cuda::std::optional<T>& val;
+  std::optional<T>& val;
 
  public:
-  parquet_field_optional(int f, cuda::std::optional<T>& v) : parquet_field(f), val(v) {}
+  parquet_field_optional(int f, std::optional<T>& v) : parquet_field(f), val(v) {}
 
   inline void operator()(CompactProtocolReader* cpr, int field_type)
   {

cpp/src/io/parquet/parquet.hpp

@@ -20,8 +20,6 @@
 
 #include <cudf/types.hpp>
 
-#include <cuda/std/optional>
-
 #include <cstdint>
 #include <optional>
 #include <string>
@@ -94,10 +92,10 @@ struct LogicalType {
     BSON
   };
   Type type;
-  cuda::std::optional<DecimalType> decimal_type;
-  cuda::std::optional<TimeType> time_type;
-  cuda::std::optional<TimestampType> timestamp_type;
-  cuda::std::optional<IntType> int_type;
+  std::optional<DecimalType> decimal_type;
+  std::optional<TimeType> time_type;
+  std::optional<TimestampType> timestamp_type;
+  std::optional<IntType> int_type;
 
   LogicalType(Type tp = UNDEFINED) : type(tp) {}
   LogicalType(DecimalType&& dt) : type(DECIMAL), decimal_type(dt) {}
@@ -178,21 +176,21 @@ struct SchemaElement {
   // 5: nested fields
   int32_t num_children = 0;
   // 6: DEPRECATED: record the original type before conversion to parquet type
-  cuda::std::optional<ConvertedType> converted_type;
+  std::optional<ConvertedType> converted_type;
   // 7: DEPRECATED: record the scale for DECIMAL converted type
   int32_t decimal_scale = 0;
   // 8: DEPRECATED: record the precision for DECIMAL converted type
   int32_t decimal_precision = 0;
   // 9: save field_id from original schema
-  cuda::std::optional<int32_t> field_id;
+  std::optional<int32_t> field_id;
   // 10: replaces converted type
-  cuda::std::optional<LogicalType> logical_type;
+  std::optional<LogicalType> logical_type;
 
   // extra cudf specific fields
   bool output_as_byte_array = false;
 
   // cudf type determined from arrow:schema
-  cuda::std::optional<type_id> arrow_type;
+  std::optional<type_id> arrow_type;
 
   // The following fields are filled in later during schema initialization
   int max_definition_level = 0;
@@ -258,21 +256,21 @@ struct SchemaElement {
  */
 struct Statistics {
   // deprecated max value in signed comparison order
-  cuda::std::optional<std::vector<uint8_t>> max;
+  std::optional<std::vector<uint8_t>> max;
   // deprecated min value in signed comparison order
-  cuda::std::optional<std::vector<uint8_t>> min;
+  std::optional<std::vector<uint8_t>> min;
   // count of null values in the column
-  cuda::std::optional<int64_t> null_count;
+  std::optional<int64_t> null_count;
   // count of distinct values occurring
-  cuda::std::optional<int64_t> distinct_count;
+  std::optional<int64_t> distinct_count;
   // max value for column determined by ColumnOrder
-  cuda::std::optional<std::vector<uint8_t>> max_value;
+  std::optional<std::vector<uint8_t>> max_value;
   // min value for column determined by ColumnOrder
-  cuda::std::optional<std::vector<uint8_t>> min_value;
+  std::optional<std::vector<uint8_t>> min_value;
   // If true, max_value is the actual maximum value for a column
-  cuda::std::optional<bool> is_max_value_exact;
+  std::optional<bool> is_max_value_exact;
   // If true, min_value is the actual minimum value for a column
-  cuda::std::optional<bool> is_min_value_exact;
+  std::optional<bool> is_min_value_exact;
 };
 
 /**
@@ -281,7 +279,7 @@ struct Statistics {
 struct SizeStatistics {
   // Number of variable-width bytes stored for the page/chunk. Should not be set for anything
   // but the BYTE_ARRAY physical type.
-  cuda::std::optional<int64_t> unencoded_byte_array_data_bytes;
+  std::optional<int64_t> unencoded_byte_array_data_bytes;
   /**
    * When present, there is expected to be one element corresponding to each
    * repetition (i.e. size=max repetition_level+1) where each element
@@ -290,14 +288,14 @@ struct SizeStatistics {
    *
    * This value should not be written if max_repetition_level is 0.
    */
-  cuda::std::optional<std::vector<int64_t>> repetition_level_histogram;
+  std::optional<std::vector<int64_t>> repetition_level_histogram;
 
   /**
    * Same as repetition_level_histogram except for definition levels.
    *
    * This value should not be written if max_definition_level is 0 or 1.
    */
-  cuda::std::optional<std::vector<int64_t>> definition_level_histogram;
+  std::optional<std::vector<int64_t>> definition_level_histogram;
 };
 
 /**
@@ -318,7 +316,7 @@ struct OffsetIndex {
   std::vector<PageLocation> page_locations;
   // per-page size info. see description of the same field in SizeStatistics. only present for
   // columns with a BYTE_ARRAY physical type.
-  cuda::std::optional<std::vector<int64_t>> unencoded_byte_array_data_bytes;
+  std::optional<std::vector<int64_t>> unencoded_byte_array_data_bytes;
 };
 
 /**
@@ -329,11 +327,11 @@ struct ColumnIndex {
   std::vector<std::vector<uint8_t>> min_values;  // lower bound for values in each page
   std::vector<std::vector<uint8_t>> max_values;  // upper bound for values in each page
   BoundaryOrder boundary_order =
-    BoundaryOrder::UNORDERED;  // Indicates if min and max values are ordered
-  cuda::std::optional<std::vector<int64_t>> null_counts;  // Optional count of null values per page
+    BoundaryOrder::UNORDERED;                       // Indicates if min and max values are ordered
+  std::optional<std::vector<int64_t>> null_counts;  // Optional count of null values per page
   // Repetition/definition level histograms for the column chunk
-  cuda::std::optional<std::vector<int64_t>> repetition_level_histogram;
-  cuda::std::optional<std::vector<int64_t>> definition_level_histogram;
+  std::optional<std::vector<int64_t>> repetition_level_histogram;
+  std::optional<std::vector<int64_t>> definition_level_histogram;
 };
 
 /**
@@ -383,11 +381,11 @@ struct ColumnChunkMetaData {
   Statistics statistics;
   // Set of all encodings used for pages in this column chunk. This information can be used to
   // determine if all data pages are dictionary encoded for example.
-  cuda::std::optional<std::vector<PageEncodingStats>> encoding_stats;
+  std::optional<std::vector<PageEncodingStats>> encoding_stats;
   // Optional statistics to help estimate total memory when converted to in-memory representations.
   // The histograms contained in these statistics can also be useful in some cases for more
   // fine-grained nullability/list length filter pushdown.
-  cuda::std::optional<SizeStatistics> size_statistics;
+  std::optional<SizeStatistics> size_statistics;
 };
 
 /**
@@ -429,13 +427,13 @@ struct RowGroup {
   int64_t num_rows = 0;
   // If set, specifies a sort ordering of the rows in this RowGroup.
   // The sorting columns can be a subset of all the columns.
-  cuda::std::optional<std::vector<SortingColumn>> sorting_columns;
+  std::optional<std::vector<SortingColumn>> sorting_columns;
   // Byte offset from beginning of file to first page (data or dictionary) in this row group
-  cuda::std::optional<int64_t> file_offset;
+  std::optional<int64_t> file_offset;
   // Total byte size of all compressed (and potentially encrypted) column data in this row group
-  cuda::std::optional<int64_t> total_compressed_size;
+  std::optional<int64_t> total_compressed_size;
   // Row group ordinal in the file
-  cuda::std::optional<int16_t> ordinal;
+  std::optional<int16_t> ordinal;
 };
 
 /**
@@ -460,7 +458,7 @@ struct FileMetaData {
   std::vector<RowGroup> row_groups;
   std::vector<KeyValue> key_value_metadata;
   std::string created_by = "";
-  cuda::std::optional<std::vector<ColumnOrder>> column_orders;
+  std::optional<std::vector<ColumnOrder>> column_orders;
 };
 
 /**

cpp/src/io/parquet/parquet_gpu.hpp

@@ -395,7 +395,7 @@ struct ColumnChunkDesc {
                            uint8_t def_level_bits_,
                            uint8_t rep_level_bits_,
                            Compression codec_,
-                           cuda::std::optional<LogicalType> logical_type_,
+                           std::optional<LogicalType> logical_type_,
                            int32_t ts_clock_rate_,
                            int32_t src_col_index_,
                            int32_t src_col_schema_,
@@ -441,12 +441,12 @@ struct ColumnChunkDesc {
   int32_t num_data_pages{};                           // number of data pages
   int32_t num_dict_pages{};                           // number of dictionary pages
   PageInfo const* dict_page{};
-  string_index_pair* str_dict_index{};  // index for string dictionary
-  bitmask_type** valid_map_base{};      // base pointers of valid bit map for this column
-  void** column_data_base{};            // base pointers of column data
-  void** column_string_base{};          // base pointers of column string data
-  Compression codec{};                  // compressed codec enum
-  cuda::std::optional<LogicalType> logical_type{};  // logical type
+  string_index_pair* str_dict_index{};        // index for string dictionary
+  bitmask_type** valid_map_base{};            // base pointers of valid bit map for this column
+  void** column_data_base{};                  // base pointers of column data
+  void** column_string_base{};                // base pointers of column string data
+  Compression codec{};                        // compressed codec enum
+  std::optional<LogicalType> logical_type{};  // logical type
   int32_t ts_clock_rate{};  // output timestamp clock frequency (0=default, 1000=ms, 1000000000=ns)
 
   int32_t src_col_index{};   // my input column index

cpp/src/io/parquet/predicate_pushdown.cpp

@@ -152,7 +152,7 @@ struct stats_caster {
         }
 
         void set_index(size_type index,
-                       cuda::std::optional<std::vector<uint8_t>> const& binary_value,
+                       std::optional<std::vector<uint8_t>> const& binary_value,
                        Type const type)
         {
           if (binary_value.has_value()) {
@@ -234,8 +234,8 @@ struct stats_caster {
             max.set_index(stats_idx, max_value, colchunk.meta_data.type);
           } else {
             // Marking it null, if column present in row group
-            min.set_index(stats_idx, cuda::std::nullopt, {});
-            max.set_index(stats_idx, cuda::std::nullopt, {});
+            min.set_index(stats_idx, std::nullopt, {});
+            max.set_index(stats_idx, std::nullopt, {});
           }
           stats_idx++;
         }

cpp/src/io/parquet/reader_impl.cpp

@@ -38,7 +38,7 @@ namespace {
 // be treated as a string. Currently the only logical type that has special handling is DECIMAL.
 // Other valid types in the future would be UUID (still treated as string) and FLOAT16 (which
 // for now would also be treated as a string).
-inline bool is_treat_fixed_length_as_string(cuda::std::optional<LogicalType> const& logical_type)
+inline bool is_treat_fixed_length_as_string(std::optional<LogicalType> const& logical_type)
 {
   if (!logical_type.has_value()) { return true; }
   return logical_type->type != LogicalType::DECIMAL;

cpp/src/io/parquet/reader_impl_chunking.cu

@@ -371,11 +371,11 @@ int64_t find_next_split(int64_t cur_pos,
  *
  * @return A tuple of Parquet clock rate and Parquet decimal type.
  */
-[[nodiscard]] std::tuple<int32_t, cuda::std::optional<LogicalType>> conversion_info(
+[[nodiscard]] std::tuple<int32_t, std::optional<LogicalType>> conversion_info(
   type_id column_type_id,
   type_id timestamp_type_id,
   Type physical,
-  cuda::std::optional<LogicalType> logical_type)
+  std::optional<LogicalType> logical_type)
 {
   int32_t const clock_rate =
     is_chrono(data_type{column_type_id}) ? to_clockrate(timestamp_type_id) : 0;
@@ -386,11 +386,11 @@ int64_t find_next_split(int64_t cur_pos,
     // if decimal but not outputting as float or decimal, then convert to no logical type
     if (column_type_id != type_id::FLOAT64 and
         not cudf::is_fixed_point(data_type{column_type_id})) {
-      return std::make_tuple(clock_rate, cuda::std::nullopt);
+      return {clock_rate, std::nullopt};
     }
   }
 
-  return std::make_tuple(clock_rate, std::move(logical_type));
+  return {clock_rate, std::move(logical_type)};
 }
 
 /**

cpp/src/io/parquet/reader_impl_helpers.cpp

@@ -38,7 +38,7 @@ namespace flatbuf = cudf::io::parquet::flatbuf;
 
 namespace {
 
-cuda::std::optional<LogicalType> converted_to_logical_type(SchemaElement const& schema)
+std::optional<LogicalType> converted_to_logical_type(SchemaElement const& schema)
 {
   if (schema.converted_type.has_value()) {
     switch (schema.converted_type.value()) {
@@ -66,7 +66,7 @@ cuda::std::optional<LogicalType> converted_to_logical_type(SchemaElement const&
       default: return LogicalType{LogicalType::UNDEFINED};
     }
   }
-  return cuda::std::nullopt;
+  return std::nullopt;
 }
 
 }  // namespace
@@ -246,7 +246,7 @@ void metadata::sanitize_schema()
         struct_elem.repetition_type = REQUIRED;
         struct_elem.num_children    = schema_elem.num_children;
         struct_elem.type            = UNDEFINED_TYPE;
-        struct_elem.converted_type  = cuda::std::nullopt;
+        struct_elem.converted_type  = std::nullopt;
 
         // swap children
         struct_elem.children_idx = std::move(schema_elem.children_idx);

cpp/src/io/parquet/writer_impl.cu

@@ -186,7 +186,7 @@ struct aggregate_writer_metadata {
     std::vector<std::vector<uint8_t>> column_indexes;
   };
   std::vector<per_file_metadata> files;
-  cuda::std::optional<std::vector<ColumnOrder>> column_orders = cuda::std::nullopt;
+  std::optional<std::vector<ColumnOrder>> column_orders = std::nullopt;
 };
 
 namespace {
@@ -472,7 +472,7 @@ struct leaf_schema_fn {
   std::enable_if_t<std::is_same_v<T, cudf::timestamp_ns>, void> operator()()
   {
     col_schema.type           = (timestamp_is_int96) ? Type::INT96 : Type::INT64;
-    col_schema.converted_type = cuda::std::nullopt;
+    col_schema.converted_type = std::nullopt;
     col_schema.stats_dtype    = statistics_dtype::dtype_timestamp64;
     if (timestamp_is_int96) {
       col_schema.ts_scale = -1000;  // negative value indicates division by absolute value
@@ -750,7 +750,7 @@ std::vector<schema_tree_node> construct_parquet_schema_tree(
           col_schema.type = Type::BYTE_ARRAY;
         }
 
-        col_schema.converted_type  = cuda::std::nullopt;
+        col_schema.converted_type  = std::nullopt;
         col_schema.stats_dtype     = statistics_dtype::dtype_byte_array;
         col_schema.repetition_type = col_nullable ? OPTIONAL : REQUIRED;
         col_schema.name = (schema[parent_idx].name == "list") ? "element" : col_meta.get_name();
@@ -2795,7 +2795,7 @@ std::unique_ptr<std::vector<uint8_t>> writer::merge_row_group_metadata(
   // See https://github.com/rapidsai/cudf/pull/14264#issuecomment-1778311615
   for (auto& se : md.schema) {
     if (se.logical_type.has_value() && se.logical_type.value().type == LogicalType::UNKNOWN) {
-      se.logical_type = cuda::std::nullopt;
+      se.logical_type = std::nullopt;
     }
   }
 

cpp/tests/io/parquet_common.cpp

@@ -744,7 +744,7 @@ int32_t compare(T& v1, T& v2)
 int32_t compare_binary(std::vector<uint8_t> const& v1,
                        std::vector<uint8_t> const& v2,
                        cudf::io::parquet::detail::Type ptype,
-                       cuda::std::optional<cudf::io::parquet::detail::ConvertedType> const& ctype)
+                       std::optional<cudf::io::parquet::detail::ConvertedType> const& ctype)
 {
   auto ctype_val = ctype.value_or(cudf::io::parquet::detail::UNKNOWN);
   switch (ptype) {

cpp/tests/io/parquet_common.hpp

@@ -172,7 +172,7 @@ std::pair<cudf::table, std::string> create_parquet_typed_with_stats(std::string
 int32_t compare_binary(std::vector<uint8_t> const& v1,
                        std::vector<uint8_t> const& v2,
                        cudf::io::parquet::detail::Type ptype,
-                       cuda::std::optional<cudf::io::parquet::detail::ConvertedType> const& ctype);
+                       std::optional<cudf::io::parquet::detail::ConvertedType> const& ctype);
 
 void expect_compression_stats_empty(std::shared_ptr<cudf::io::writer_compression_statistics> stats);