lib/Headers/cuda_wrappers/algorithm

/*===---- complex - CUDA wrapper for <algorithm> ----------------------------===
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 *===-----------------------------------------------------------------------===
 */

#ifndef __CLANG_CUDA_WRAPPERS_ALGORITHM
#define __CLANG_CUDA_WRAPPERS_ALGORITHM

// This header defines __device__ overloads of std::min/max, but only if we're
// <= C++11.  In C++14, these functions are constexpr, and so are implicitly
// __host__ __device__.
//
// We don't support the initializer_list overloads because
// initializer_list::begin() and end() are not __host__ __device__ functions.
//
// When compiling in C++14 mode, we could force std::min/max to have different
// implementations for host and device, by declaring the device overloads
// before the constexpr overloads appear.  We choose not to do this because

//  a) why write our own implementation when we can use one from the standard
//     library? and
//  b) libstdc++ is evil and declares min/max inside a header that is included
//     *before* we include <algorithm>.  So we'd have to unconditionally
//     declare our __device__ overloads of min/max, but that would pollute
//     things for people who choose not to include <algorithm>.

#include_next <algorithm>

#if __cplusplus <= 201103L

// We need to define these overloads in exactly the namespace our standard
// library uses (including the right inline namespace), otherwise they won't be
// picked up by other functions in the standard library (e.g. functions in
// <complex>).  Thus the ugliness below.
#ifdef _LIBCPP_BEGIN_NAMESPACE_STD
_LIBCPP_BEGIN_NAMESPACE_STD
#else
namespace std {
#ifdef _GLIBCXX_BEGIN_NAMESPACE_VERSION
_GLIBCXX_BEGIN_NAMESPACE_VERSION
#endif
#endif

template <class __T, class __Cmp>
inline __device__ const __T &
max(const __T &__a, const __T &__b, __Cmp __cmp) {
  return __cmp(__a, __b) ? __b : __a;
}

template <class __T>
inline __device__ const __T &
max(const __T &__a, const __T &__b) {
  return __a < __b ? __b : __a;
}

template <class __T, class __Cmp>
inline __device__ const __T &
min(const __T &__a, const __T &__b, __Cmp __cmp) {
  return __cmp(__b, __a) ? __b : __a;
}

template <class __T>
inline __device__ const __T &
min(const __T &__a, const __T &__b) {
  return __a < __b ? __b : __a;
}

#ifdef _LIBCPP_END_NAMESPACE_STD
_LIBCPP_END_NAMESPACE_STD
#else
#ifdef _GLIBCXX_BEGIN_NAMESPACE_VERSION
_GLIBCXX_END_NAMESPACE_VERSION
#endif
} // namespace std
#endif

#endif // __cplusplus <= 201103L
#endif // __CLANG_CUDA_WRAPPERS_ALGORITHM