cub/device/device_reduce.cuh

File members: cub/device/device_reduce.cuh

/******************************************************************************
 * Copyright (c) 2011, Duane Merrill.  All rights reserved.
 * Copyright (c) 2011-2024, NVIDIA CORPORATION.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the NVIDIA CORPORATION nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL NVIDIA CORPORATION BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 ******************************************************************************/

#pragma once

#include <cub/config.cuh>

#if defined(_CCCL_IMPLICIT_SYSTEM_HEADER_GCC)
#  pragma GCC system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_CLANG)
#  pragma clang system_header
#elif defined(_CCCL_IMPLICIT_SYSTEM_HEADER_MSVC)
#  pragma system_header
#endif // no system header

#include <cub/detail/choose_offset.cuh>
#include <cub/detail/nvtx.cuh>
#include <cub/device/dispatch/dispatch_reduce.cuh>
#include <cub/device/dispatch/dispatch_reduce_by_key.cuh>
#include <cub/iterator/arg_index_input_iterator.cuh>
#include <cub/util_deprecated.cuh>

#include <iterator>
#include <limits>

CUB_NAMESPACE_BEGIN

struct DeviceReduce
{
  template <typename InputIteratorT, typename OutputIteratorT, typename ReductionOpT, typename T, typename NumItemsT>
  CUB_RUNTIME_FUNCTION static cudaError_t Reduce(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    InputIteratorT d_in,
    OutputIteratorT d_out,
    NumItemsT num_items,
    ReductionOpT reduction_op,
    T init,
    cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::Reduce");

    // Signed integer type for global offsets
    using OffsetT = detail::choose_offset_t<NumItemsT>;

    return DispatchReduce<InputIteratorT, OutputIteratorT, OffsetT, ReductionOpT, T>::Dispatch(
      d_temp_storage, temp_storage_bytes, d_in, d_out, static_cast<OffsetT>(num_items), reduction_op, init, stream);
  }

#ifndef _CCCL_DOXYGEN_INVOKED // Do not document
  template <typename InputIteratorT, typename OutputIteratorT, typename ReductionOpT, typename T>
  CUB_DETAIL_RUNTIME_DEBUG_SYNC_IS_NOT_SUPPORTED CUB_RUNTIME_FUNCTION static cudaError_t Reduce(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    InputIteratorT d_in,
    OutputIteratorT d_out,
    int num_items,
    ReductionOpT reduction_op,
    T init,
    cudaStream_t stream,
    bool debug_synchronous)
  {
    CUB_DETAIL_RUNTIME_DEBUG_SYNC_USAGE_LOG

    return Reduce<InputIteratorT, OutputIteratorT, ReductionOpT, T>(
      d_temp_storage, temp_storage_bytes, d_in, d_out, num_items, reduction_op, init, stream);
  }
#endif // _CCCL_DOXYGEN_INVOKED

  template <typename InputIteratorT, typename OutputIteratorT, typename NumItemsT>
  CUB_RUNTIME_FUNCTION static cudaError_t
  Sum(void* d_temp_storage,
      size_t& temp_storage_bytes,
      InputIteratorT d_in,
      OutputIteratorT d_out,
      NumItemsT num_items,
      cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::Sum");

    // Signed integer type for global offsets
    using OffsetT = detail::choose_offset_t<NumItemsT>;

    // The output value type
    using OutputT = cub::detail::non_void_value_t<OutputIteratorT, cub::detail::value_t<InputIteratorT>>;

    using InitT = OutputT;

    return DispatchReduce<InputIteratorT, OutputIteratorT, OffsetT, ::cuda::std::plus<>, InitT>::Dispatch(
      d_temp_storage,
      temp_storage_bytes,
      d_in,
      d_out,
      static_cast<OffsetT>(num_items),
      ::cuda::std::plus<>{},
      InitT{}, // zero-initialize
      stream);
  }

#ifndef _CCCL_DOXYGEN_INVOKED // Do not document
  template <typename InputIteratorT, typename OutputIteratorT>
  CUB_DETAIL_RUNTIME_DEBUG_SYNC_IS_NOT_SUPPORTED CUB_RUNTIME_FUNCTION static cudaError_t
  Sum(void* d_temp_storage,
      size_t& temp_storage_bytes,
      InputIteratorT d_in,
      OutputIteratorT d_out,
      int num_items,
      cudaStream_t stream,
      bool debug_synchronous)
  {
    CUB_DETAIL_RUNTIME_DEBUG_SYNC_USAGE_LOG

    return Sum<InputIteratorT, OutputIteratorT>(d_temp_storage, temp_storage_bytes, d_in, d_out, num_items, stream);
  }
#endif // _CCCL_DOXYGEN_INVOKED

  template <typename InputIteratorT, typename OutputIteratorT, typename NumItemsT>
  CUB_RUNTIME_FUNCTION static cudaError_t
  Min(void* d_temp_storage,
      size_t& temp_storage_bytes,
      InputIteratorT d_in,
      OutputIteratorT d_out,
      NumItemsT num_items,
      cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::Min");

    // Signed integer type for global offsets
    using OffsetT = detail::choose_offset_t<NumItemsT>;

    // The input value type
    using InputT = cub::detail::value_t<InputIteratorT>;

    using InitT = InputT;

    return DispatchReduce<InputIteratorT, OutputIteratorT, OffsetT, ::cuda::minimum<>, InitT>::Dispatch(
      d_temp_storage,
      temp_storage_bytes,
      d_in,
      d_out,
      static_cast<OffsetT>(num_items),
      ::cuda::minimum<>{},
      // replace with
      // std::numeric_limits<T>::max() when
      // C++11 support is more prevalent
      Traits<InitT>::Max(),
      stream);
  }

#ifndef _CCCL_DOXYGEN_INVOKED // Do not document
  template <typename InputIteratorT, typename OutputIteratorT>
  CUB_DETAIL_RUNTIME_DEBUG_SYNC_IS_NOT_SUPPORTED CUB_RUNTIME_FUNCTION static cudaError_t
  Min(void* d_temp_storage,
      size_t& temp_storage_bytes,
      InputIteratorT d_in,
      OutputIteratorT d_out,
      int num_items,
      cudaStream_t stream,
      bool debug_synchronous)
  {
    CUB_DETAIL_RUNTIME_DEBUG_SYNC_USAGE_LOG

    return Min<InputIteratorT, OutputIteratorT>(d_temp_storage, temp_storage_bytes, d_in, d_out, num_items, stream);
  }
#endif // _CCCL_DOXYGEN_INVOKED

  template <typename InputIteratorT, typename OutputIteratorT>
  CUB_RUNTIME_FUNCTION static cudaError_t ArgMin(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    InputIteratorT d_in,
    OutputIteratorT d_out,
    int num_items,
    cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::ArgMin");

    // Signed integer type for global offsets
    using OffsetT = int;

    // The input type
    using InputValueT = cub::detail::value_t<InputIteratorT>;

    // The output tuple type
    using OutputTupleT = cub::detail::non_void_value_t<OutputIteratorT, KeyValuePair<OffsetT, InputValueT>>;

    using AccumT = OutputTupleT;

    using InitT = detail::reduce::empty_problem_init_t<AccumT>;

    // The output value type
    using OutputValueT = typename OutputTupleT::Value;

    // Wrapped input iterator to produce index-value <OffsetT, InputT> tuples
    using ArgIndexInputIteratorT = ArgIndexInputIterator<InputIteratorT, OffsetT, OutputValueT>;

    ArgIndexInputIteratorT d_indexed_in(d_in);

    // Initial value
    // TODO Address https://github.com/NVIDIA/cub/issues/651
    InitT initial_value{AccumT(1, Traits<InputValueT>::Max())};

    return DispatchReduce<ArgIndexInputIteratorT, OutputIteratorT, OffsetT, cub::ArgMin, InitT, AccumT>::Dispatch(
      d_temp_storage, temp_storage_bytes, d_indexed_in, d_out, num_items, cub::ArgMin(), initial_value, stream);
  }

#ifndef _CCCL_DOXYGEN_INVOKED // Do not document
  template <typename InputIteratorT, typename OutputIteratorT>
  CUB_DETAIL_RUNTIME_DEBUG_SYNC_IS_NOT_SUPPORTED CUB_RUNTIME_FUNCTION static cudaError_t ArgMin(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    InputIteratorT d_in,
    OutputIteratorT d_out,
    int num_items,
    cudaStream_t stream,
    bool debug_synchronous)
  {
    CUB_DETAIL_RUNTIME_DEBUG_SYNC_USAGE_LOG

    return ArgMin<InputIteratorT, OutputIteratorT>(d_temp_storage, temp_storage_bytes, d_in, d_out, num_items, stream);
  }
#endif // _CCCL_DOXYGEN_INVOKED

  template <typename InputIteratorT, typename OutputIteratorT, typename NumItemsT>
  CUB_RUNTIME_FUNCTION static cudaError_t
  Max(void* d_temp_storage,
      size_t& temp_storage_bytes,
      InputIteratorT d_in,
      OutputIteratorT d_out,
      NumItemsT num_items,
      cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::Max");

    // Signed integer type for global offsets
    using OffsetT = detail::choose_offset_t<NumItemsT>;

    // The input value type
    using InputT = cub::detail::value_t<InputIteratorT>;

    using InitT = InputT;

    return DispatchReduce<InputIteratorT, OutputIteratorT, OffsetT, ::cuda::maximum<>, InitT>::Dispatch(
      d_temp_storage,
      temp_storage_bytes,
      d_in,
      d_out,
      static_cast<OffsetT>(num_items),
      ::cuda::maximum<>{},
      // replace with
      // std::numeric_limits<T>::lowest()
      // when C++11 support is more
      // prevalent
      Traits<InitT>::Lowest(),
      stream);
  }

#ifndef _CCCL_DOXYGEN_INVOKED // Do not document
  template <typename InputIteratorT, typename OutputIteratorT>
  CUB_DETAIL_RUNTIME_DEBUG_SYNC_IS_NOT_SUPPORTED CUB_RUNTIME_FUNCTION static cudaError_t
  Max(void* d_temp_storage,
      size_t& temp_storage_bytes,
      InputIteratorT d_in,
      OutputIteratorT d_out,
      int num_items,
      cudaStream_t stream,
      bool debug_synchronous)
  {
    CUB_DETAIL_RUNTIME_DEBUG_SYNC_USAGE_LOG

    return Max<InputIteratorT, OutputIteratorT>(d_temp_storage, temp_storage_bytes, d_in, d_out, num_items, stream);
  }
#endif // _CCCL_DOXYGEN_INVOKED

  template <typename InputIteratorT, typename OutputIteratorT>
  CUB_RUNTIME_FUNCTION static cudaError_t ArgMax(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    InputIteratorT d_in,
    OutputIteratorT d_out,
    int num_items,
    cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::ArgMax");

    // Signed integer type for global offsets
    using OffsetT = int;

    // The input type
    using InputValueT = cub::detail::value_t<InputIteratorT>;

    // The output tuple type
    using OutputTupleT = cub::detail::non_void_value_t<OutputIteratorT, KeyValuePair<OffsetT, InputValueT>>;

    using AccumT = OutputTupleT;

    // The output value type
    using OutputValueT = typename OutputTupleT::Value;

    using InitT = detail::reduce::empty_problem_init_t<AccumT>;

    // Wrapped input iterator to produce index-value <OffsetT, InputT> tuples
    using ArgIndexInputIteratorT = ArgIndexInputIterator<InputIteratorT, OffsetT, OutputValueT>;

    ArgIndexInputIteratorT d_indexed_in(d_in);

    // Initial value
    // TODO Address https://github.com/NVIDIA/cub/issues/651
    InitT initial_value{AccumT(1, Traits<InputValueT>::Lowest())};

    return DispatchReduce<ArgIndexInputIteratorT, OutputIteratorT, OffsetT, cub::ArgMax, InitT, AccumT>::Dispatch(
      d_temp_storage, temp_storage_bytes, d_indexed_in, d_out, num_items, cub::ArgMax(), initial_value, stream);
  }

#ifndef _CCCL_DOXYGEN_INVOKED // Do not document
  template <typename InputIteratorT, typename OutputIteratorT>
  CUB_DETAIL_RUNTIME_DEBUG_SYNC_IS_NOT_SUPPORTED CUB_RUNTIME_FUNCTION static cudaError_t ArgMax(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    InputIteratorT d_in,
    OutputIteratorT d_out,
    int num_items,
    cudaStream_t stream,
    bool debug_synchronous)
  {
    CUB_DETAIL_RUNTIME_DEBUG_SYNC_USAGE_LOG

    return ArgMax<InputIteratorT, OutputIteratorT>(d_temp_storage, temp_storage_bytes, d_in, d_out, num_items, stream);
  }
#endif // _CCCL_DOXYGEN_INVOKED

  template <typename InputIteratorT,
            typename OutputIteratorT,
            typename ReductionOpT,
            typename TransformOpT,
            typename T,
            typename NumItemsT>
  CUB_RUNTIME_FUNCTION static cudaError_t TransformReduce(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    InputIteratorT d_in,
    OutputIteratorT d_out,
    NumItemsT num_items,
    ReductionOpT reduction_op,
    TransformOpT transform_op,
    T init,
    cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::TransformReduce");

    using OffsetT = detail::choose_offset_t<NumItemsT>;

    return DispatchTransformReduce<InputIteratorT, OutputIteratorT, OffsetT, ReductionOpT, TransformOpT, T>::Dispatch(
      d_temp_storage,
      temp_storage_bytes,
      d_in,
      d_out,
      static_cast<OffsetT>(num_items),
      reduction_op,
      init,
      stream,
      transform_op);
  }

  template <typename KeysInputIteratorT,
            typename UniqueOutputIteratorT,
            typename ValuesInputIteratorT,
            typename AggregatesOutputIteratorT,
            typename NumRunsOutputIteratorT,
            typename ReductionOpT,
            typename NumItemsT>
  CUB_RUNTIME_FUNCTION _CCCL_FORCEINLINE static cudaError_t ReduceByKey(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    KeysInputIteratorT d_keys_in,
    UniqueOutputIteratorT d_unique_out,
    ValuesInputIteratorT d_values_in,
    AggregatesOutputIteratorT d_aggregates_out,
    NumRunsOutputIteratorT d_num_runs_out,
    ReductionOpT reduction_op,
    NumItemsT num_items,
    cudaStream_t stream = 0)
  {
    CUB_DETAIL_NVTX_RANGE_SCOPE_IF(d_temp_storage, "cub::DeviceReduce::ReduceByKey");

    // Signed integer type for global offsets
    using OffsetT = detail::choose_offset_t<NumItemsT>;

    // FlagT iterator type (not used)

    // Selection op (not used)

    // Default == operator
    using EqualityOp = ::cuda::std::equal_to<>;

    return DispatchReduceByKey<
      KeysInputIteratorT,
      UniqueOutputIteratorT,
      ValuesInputIteratorT,
      AggregatesOutputIteratorT,
      NumRunsOutputIteratorT,
      EqualityOp,
      ReductionOpT,
      OffsetT>::Dispatch(d_temp_storage,
                         temp_storage_bytes,
                         d_keys_in,
                         d_unique_out,
                         d_values_in,
                         d_aggregates_out,
                         d_num_runs_out,
                         EqualityOp(),
                         reduction_op,
                         static_cast<OffsetT>(num_items),
                         stream);
  }

#ifndef _CCCL_DOXYGEN_INVOKED // Do not document
  template <typename KeysInputIteratorT,
            typename UniqueOutputIteratorT,
            typename ValuesInputIteratorT,
            typename AggregatesOutputIteratorT,
            typename NumRunsOutputIteratorT,
            typename ReductionOpT>
  CUB_DETAIL_RUNTIME_DEBUG_SYNC_IS_NOT_SUPPORTED CUB_RUNTIME_FUNCTION _CCCL_FORCEINLINE static cudaError_t ReduceByKey(
    void* d_temp_storage,
    size_t& temp_storage_bytes,
    KeysInputIteratorT d_keys_in,
    UniqueOutputIteratorT d_unique_out,
    ValuesInputIteratorT d_values_in,
    AggregatesOutputIteratorT d_aggregates_out,
    NumRunsOutputIteratorT d_num_runs_out,
    ReductionOpT reduction_op,
    int num_items,
    cudaStream_t stream,
    bool debug_synchronous)
  {
    CUB_DETAIL_RUNTIME_DEBUG_SYNC_USAGE_LOG

    return ReduceByKey<KeysInputIteratorT,
                       UniqueOutputIteratorT,
                       ValuesInputIteratorT,
                       AggregatesOutputIteratorT,
                       NumRunsOutputIteratorT,
                       ReductionOpT>(
      d_temp_storage,
      temp_storage_bytes,
      d_keys_in,
      d_unique_out,
      d_values_in,
      d_aggregates_out,
      d_num_runs_out,
      reduction_op,
      num_items,
      stream);
  }
#endif // _CCCL_DOXYGEN_INVOKED
};

CUB_NAMESPACE_END