thread_sort.cuh

File members: /home/runner/work/cccl/cccl/cub/cub/thread/thread_sort.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 <cuda/std/type_traits>

CUB_NAMESPACE_BEGIN

template <typename T>
_CCCL_DEVICE _CCCL_FORCEINLINE void Swap(T& lhs, T& rhs)
{
  T temp = lhs;
  lhs    = rhs;
  rhs    = temp;
}

template <typename KeyT, typename ValueT, typename CompareOp, int ITEMS_PER_THREAD>
_CCCL_DEVICE _CCCL_FORCEINLINE void
StableOddEvenSort(KeyT (&keys)[ITEMS_PER_THREAD], ValueT (&items)[ITEMS_PER_THREAD], CompareOp compare_op)
{
  constexpr bool KEYS_ONLY = ::cuda::std::is_same<ValueT, NullType>::value;

#pragma unroll
  for (int i = 0; i < ITEMS_PER_THREAD; ++i)
  {
#pragma unroll
    for (int j = 1 & i; j < ITEMS_PER_THREAD - 1; j += 2)
    {
      if (compare_op(keys[j + 1], keys[j]))
      {
        Swap(keys[j], keys[j + 1]);
        if (!KEYS_ONLY)
        {
          Swap(items[j], items[j + 1]);
        }
      }
    } // inner loop
  } // outer loop
}

CUB_NAMESPACE_END