warp_exchange.cuh

File members: /home/runner/work/cccl/cccl/cub/cub/warp/warp_exchange.cuh
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#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/util_ptx.cuh>
#include <cub/util_type.cuh>
#include <cub/warp/specializations/warp_exchange_shfl.cuh>
#include <cub/warp/specializations/warp_exchange_smem.cuh>

CUB_NAMESPACE_BEGIN

enum WarpExchangeAlgorithm
{
  WARP_EXCHANGE_SMEM,
  WARP_EXCHANGE_SHUFFLE,
};

namespace detail
{
template <typename InputT, int ITEMS_PER_THREAD, int LOGICAL_WARP_THREADS, WarpExchangeAlgorithm WARP_EXCHANGE_ALGORITHM>
using InternalWarpExchangeImpl =
  cub::detail::conditional_t<WARP_EXCHANGE_ALGORITHM == WARP_EXCHANGE_SMEM,
                             WarpExchangeSmem<InputT, ITEMS_PER_THREAD, LOGICAL_WARP_THREADS>,
                             WarpExchangeShfl<InputT, ITEMS_PER_THREAD, LOGICAL_WARP_THREADS>>;
} // namespace detail

template <typename InputT,
          int ITEMS_PER_THREAD,
          int LOGICAL_WARP_THREADS                      = CUB_PTX_WARP_THREADS,
          int LEGACY_PTX_ARCH                           = 0,
          WarpExchangeAlgorithm WARP_EXCHANGE_ALGORITHM = WARP_EXCHANGE_SMEM>
class WarpExchange
    : private detail::InternalWarpExchangeImpl<InputT, ITEMS_PER_THREAD, LOGICAL_WARP_THREADS, WARP_EXCHANGE_ALGORITHM>
{
  using InternalWarpExchange =
    detail::InternalWarpExchangeImpl<InputT, ITEMS_PER_THREAD, LOGICAL_WARP_THREADS, WARP_EXCHANGE_ALGORITHM>;

public:
  using TempStorage = typename InternalWarpExchange::TempStorage;

  WarpExchange() = delete;

  explicit _CCCL_DEVICE _CCCL_FORCEINLINE WarpExchange(TempStorage& temp_storage)
      : InternalWarpExchange(temp_storage)
  {}

  template <typename OutputT>
  _CCCL_DEVICE _CCCL_FORCEINLINE void
  BlockedToStriped(const InputT (&input_items)[ITEMS_PER_THREAD], OutputT (&output_items)[ITEMS_PER_THREAD])
  {
    InternalWarpExchange::BlockedToStriped(input_items, output_items);
  }

  template <typename OutputT>
  _CCCL_DEVICE _CCCL_FORCEINLINE void
  StripedToBlocked(const InputT (&input_items)[ITEMS_PER_THREAD], OutputT (&output_items)[ITEMS_PER_THREAD])
  {
    InternalWarpExchange::StripedToBlocked(input_items, output_items);
  }

  template <typename OffsetT>
  _CCCL_DEVICE _CCCL_FORCEINLINE void
  ScatterToStriped(InputT (&items)[ITEMS_PER_THREAD], OffsetT (&ranks)[ITEMS_PER_THREAD])
  {
    InternalWarpExchange::ScatterToStriped(items, ranks);
  }

  template <typename OutputT, typename OffsetT>
  _CCCL_DEVICE _CCCL_FORCEINLINE void ScatterToStriped(
    const InputT (&input_items)[ITEMS_PER_THREAD],
    OutputT (&output_items)[ITEMS_PER_THREAD],
    OffsetT (&ranks)[ITEMS_PER_THREAD])
  {
    InternalWarpExchange::ScatterToStriped(input_items, output_items, ranks);
  }

};

CUB_NAMESPACE_END