Kokkos_Pair.hpp

Go to the documentation of this file.

//@HEADER
// ************************************************************************
//
//                        Kokkos v. 2.0
//              Copyright (2014) Sandia Corporation
//
// Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
// the U.S. Government retains certain rights in this software.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// 2. 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.
//
// 3. Neither the name of the Corporation nor the names of the
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY SANDIA CORPORATION "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 SANDIA CORPORATION OR THE
// CONTRIBUTORS 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.
//
// Questions? Contact Christian R. Trott (crtrott@sandia.gov)
//
// ************************************************************************
//@HEADER


#ifndef KOKKOS_PAIR_HPP
#define KOKKOS_PAIR_HPP

#include <Kokkos_Macros.hpp>
#include <utility>

namespace Kokkos {
template <class T1, class T2>
struct pair
{
  typedef T1 first_type;
  typedef T2 second_type;

  first_type  first;
  second_type second;

  KOKKOS_FORCEINLINE_FUNCTION constexpr
#ifdef KOKKOS_CUDA_9_DEFAULTED_BUG_WORKAROUND
  pair() : first(), second() {}
#else
  pair() = default;
#endif

  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair(first_type const& f, second_type const& s)
    : first(f), second(s)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair( const pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair( const volatile pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION
  pair<T1, T2> & operator=(const pair<U,V> &p)
  {
    first = p.first;
    second = p.second;
    return *this;
  }


  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION
  void operator=(const volatile pair<U,V> &p) volatile
  {
    first = p.first;
    second = p.second;
    // We deliberately do not return anything here.  See explanation
    // in public documentation above.
  }

  // from std::pair<U,V>
  template <class U, class V>
  pair( const std::pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  std::pair<T1,T2> to_std_pair() const
  { return std::make_pair(first,second); }
};

template <class T1, class T2>
struct pair<T1&, T2&>
{
  typedef T1& first_type;
  typedef T2& second_type;

  first_type  first;
  second_type second;

  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair(first_type f, second_type s)
    : first(f), second(s)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair( const pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  // from std::pair<U,V>
  template <class U, class V>
  pair( const std::pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION
  pair<first_type, second_type> & operator=(const pair<U,V> &p)
  {
    first = p.first;
    second = p.second;
    return *this;
  }

  std::pair<T1,T2> to_std_pair() const
  { return std::make_pair(first,second); }
};

template <class T1, class T2>
struct pair<T1, T2&>
{
  typedef T1  first_type;
  typedef T2& second_type;

  first_type  first;
  second_type second;

  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair(first_type const& f, second_type s)
    : first(f), second(s)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair( const pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  // from std::pair<U,V>
  template <class U, class V>
  pair( const std::pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION
  pair<first_type, second_type> & operator=(const pair<U,V> &p)
  {
    first = p.first;
    second = p.second;
    return *this;
  }

  std::pair<T1,T2> to_std_pair() const
  { return std::make_pair(first,second); }
};

template <class T1, class T2>
struct pair<T1&, T2>
{
  typedef T1&  first_type;
  typedef T2 second_type;

  first_type  first;
  second_type second;

  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair(first_type f, second_type const& s)
    : first(f), second(s)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair( const pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  // from std::pair<U,V>
  template <class U, class V>
  pair( const std::pair<U,V> &p)
    : first(p.first), second(p.second)
  {}

  template <class U, class V>
  KOKKOS_FORCEINLINE_FUNCTION
  pair<first_type, second_type> & operator=(const pair<U,V> &p)
  {
    first = p.first;
    second = p.second;
    return *this;
  }

  std::pair<T1,T2> to_std_pair() const
  { return std::make_pair(first,second); }
};

template <class T1, class T2>
KOKKOS_FORCEINLINE_FUNCTION
bool operator== (const pair<T1,T2>& lhs, const pair<T1,T2>& rhs)
{ return lhs.first==rhs.first && lhs.second==rhs.second; }

template <class T1, class T2>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator!= (const pair<T1,T2>& lhs, const pair<T1,T2>& rhs)
{ return !(lhs==rhs); }

template <class T1, class T2>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator<  (const pair<T1,T2>& lhs, const pair<T1,T2>& rhs)
{ return lhs.first<rhs.first || (!(rhs.first<lhs.first) && lhs.second<rhs.second); }

template <class T1, class T2>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator<= (const pair<T1,T2>& lhs, const pair<T1,T2>& rhs)
{ return !(rhs<lhs); }

template <class T1, class T2>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator>  (const pair<T1,T2>& lhs, const pair<T1,T2>& rhs)
{ return rhs<lhs; }

template <class T1, class T2>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator>= (const pair<T1,T2>& lhs, const pair<T1,T2>& rhs)
{ return !(lhs<rhs); }

template <class T1,class T2>
KOKKOS_FORCEINLINE_FUNCTION constexpr
pair<T1,T2> make_pair (T1 x, T2 y)
{ return ( pair<T1,T2>(x,y) ); }

template <class T1,class T2>
KOKKOS_FORCEINLINE_FUNCTION
pair<T1 &,T2 &> tie (T1 & x, T2 & y)
{ return ( pair<T1 &,T2 &>(x,y) ); }

//
// Specialization of Kokkos::pair for a \c void second argument.  This
// is not actually a "pair"; it only contains one element, the first.
//
template <class T1>
struct pair<T1,void>
{
  typedef T1 first_type;
  typedef void second_type;

  first_type  first;
  enum { second = 0 };

  KOKKOS_FORCEINLINE_FUNCTION constexpr
#ifdef KOKKOS_CUDA_9_DEFAULTED_BUG_WORKAROUND
  pair() : first() {}
#else
  pair() = default;
#endif

  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair(const first_type & f)
    : first(f)
  {}

  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair(const first_type & f, int)
    : first(f)
  {}

  template <class U>
  KOKKOS_FORCEINLINE_FUNCTION constexpr
  pair( const pair<U,void> &p)
    : first(p.first)
  {}

  template <class U>
  KOKKOS_FORCEINLINE_FUNCTION
  pair<T1, void> & operator=(const pair<U,void> &p)
  {
    first = p.first;
    return *this;
  }
};

//
// Specialization of relational operators for Kokkos::pair<T1,void>.
//

template <class T1>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator== (const pair<T1,void>& lhs, const pair<T1,void>& rhs)
{ return lhs.first==rhs.first; }

template <class T1>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator!= (const pair<T1,void>& lhs, const pair<T1,void>& rhs)
{ return !(lhs==rhs); }

template <class T1>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator<  (const pair<T1,void>& lhs, const pair<T1,void>& rhs)
{ return lhs.first<rhs.first; }

template <class T1>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator<= (const pair<T1,void>& lhs, const pair<T1,void>& rhs)
{ return !(rhs<lhs); }

template <class T1>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator>  (const pair<T1,void>& lhs, const pair<T1,void>& rhs)
{ return rhs<lhs; }

template <class T1>
KOKKOS_FORCEINLINE_FUNCTION constexpr
bool operator>= (const pair<T1,void>& lhs, const pair<T1,void>& rhs)
{ return !(lhs<rhs); }


namespace Impl {

template <class T> struct is_pair_like : std::false_type { };
template <class T, class U> struct is_pair_like<Kokkos::pair<T, U>> : std::true_type { };
template <class T, class U> struct is_pair_like<std::pair<T, U>> : std::true_type { };

} // end namespace Impl

} // namespace Kokkos


#endif //KOKKOS_PAIR_HPP