TheRock/rocm-libraries/projects/rocthrust/thrust/system/hip/hipstdpar/impl/partitioning.hpp

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/*
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
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 *
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 *
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 *  distributed under the License is distributed on an "AS IS" BASIS,
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/*! \file thrust/system/hip/hipstdpar/impl/partitioning.hpp
 *  \brief <tt>Partitioning operations</tt> implementation detail header for HIPSTDPAR.
 */

#pragma once

#if defined(__HIPSTDPAR__)

#  include <thrust/execution_policy.h>
#  include <thrust/partition.h>

#  include <algorithm>
#  include <execution>
#  include <utility>

#  include "hipstd.hpp"

namespace std
{
// BEGIN IS_PARTITIONED
template <typename I,
          typename P,
          enable_if_t<::hipstd::is_offloadable_iterator<I>() && ::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline bool is_partitioned(execution::parallel_unsequenced_policy, I f, I l, P p)
{
  ::hipstd::__maybe_bind_globals();

  ::hipstd::warn_if_no_xnack();
  return ::thrust::is_partitioned(::thrust::device, f, l, ::std::move(p));
}

template <typename I,
          typename P,
          enable_if_t<!::hipstd::is_offloadable_iterator<I>() || !::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline bool is_partitioned(execution::parallel_unsequenced_policy, I f, I l, P p)
{
  if constexpr (!::hipstd::is_offloadable_iterator<I>())
  {
    ::hipstd::unsupported_iterator_category<typename iterator_traits<I>::iterator_category>();
  }
  if constexpr (!::hipstd::is_offloadable_callable<P>())
  {
    ::hipstd::unsupported_callable_type<P>();
  }

  return ::std::is_partitioned(::std::execution::par, f, l, ::std::move(p));
}
// END IS_PARTITIONED

// BEGIN PARTITION
template <typename I,
          typename P,
          enable_if_t<::hipstd::is_offloadable_iterator<I>() && ::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline I partition(execution::parallel_unsequenced_policy, I f, I l, P p)
{
  ::hipstd::__maybe_bind_globals();

  ::hipstd::warn_if_no_xnack();
  return ::thrust::partition(::thrust::device, f, l, ::std::move(p));
}

template <typename I,
          typename P,
          enable_if_t<!::hipstd::is_offloadable_iterator<I>() || !::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline I partition(execution::parallel_unsequenced_policy, I f, I l, P p)
{
  if constexpr (!::hipstd::is_offloadable_iterator<I>())
  {
    ::hipstd::unsupported_iterator_category<typename iterator_traits<I>::iterator_category>();
  }
  if constexpr (!::hipstd::is_offloadable_callable<P>())
  {
    ::hipstd::unsupported_callable_type<P>();
  }

  return ::std::partition(::std::execution::par, f, l, ::std::move(p));
}
// END PARTITION

// BEGIN PARTITION_COPY
template <
  typename I,
  typename O0,
  typename O1,
  typename P,
  enable_if_t<::hipstd::is_offloadable_iterator<I, O0, O1>() && ::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline pair<O0, O1> partition_copy(execution::parallel_unsequenced_policy, I f, I l, O0 fo0, O1 fo1, P p)
{
  ::hipstd::__maybe_bind_globals();

  ::hipstd::warn_if_no_xnack();
  auto [r0, r1] = ::thrust::partition_copy(::thrust::device, f, l, fo0, fo1, ::std::move(p));

  return {::std::move(r0), ::std::move(r1)};
}

template <
  typename I,
  typename O0,
  typename O1,
  typename P,
  enable_if_t<!::hipstd::is_offloadable_iterator<I, O0, O1>() || !::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline pair<O0, O1> partition_copy(execution::parallel_unsequenced_policy, I f, I l, O0 fo0, O1 fo1, P p)
{
  if constexpr (!::hipstd::is_offloadable_iterator<I, O0, O1>())
  {
    ::hipstd::unsupported_iterator_category<typename iterator_traits<I>::iterator_category,
                                            typename iterator_traits<O0>::iterator_category,
                                            typename iterator_traits<O1>::iterator_category>();
  }
  if constexpr (!::hipstd::is_offloadable_callable<P>())
  {
    ::hipstd::unsupported_callable_type<P>();
  }

  return ::std::partition_copy(::std::execution::par, f, l, fo0, fo1, ::std::move(p));
}
// END PARTITION_COPY

// BEGIN STABLE_PARTITION
template <typename I,
          typename P,
          enable_if_t<::hipstd::is_offloadable_iterator<I>() && ::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline I stable_partition(execution::parallel_unsequenced_policy, I f, I l, P p)
{
  ::hipstd::__maybe_bind_globals();

  ::hipstd::warn_if_no_xnack();
  return ::thrust::stable_partition(::thrust::device, f, l, ::std::move(p));
}

template <typename I,
          typename P,
          enable_if_t<!::hipstd::is_offloadable_iterator<I>() || !::hipstd::is_offloadable_callable<P>()>* = nullptr>
inline I stable_partition(execution::parallel_unsequenced_policy, I f, I l, P p)
{
  if constexpr (!::hipstd::is_offloadable_iterator<I>())
  {
    ::hipstd::unsupported_iterator_category<typename iterator_traits<I>::iterator_category>();
  }
  if constexpr (!::hipstd::is_offloadable_callable<P>())
  {
    ::hipstd::unsupported_callable_type<P>();
  }

  return ::std::stable_partition(::std::execution::par, f, l, ::std::move(p));
}
// END STABLE_PARTITION
} // namespace std
#else // __HIPSTDPAR__
#  error "__HIPSTDPAR__ should be defined. Please use the '--hipstdpar' compile option."
#endif // __HIPSTDPAR__