1 //===----------------------------------------------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef _LIBCPP___PSTL_CPU_ALGOS_STABLE_SORT_H 10 #define _LIBCPP___PSTL_CPU_ALGOS_STABLE_SORT_H 11 12 #include <__algorithm/stable_sort.h> 13 #include <__config> 14 #include <__pstl/backend_fwd.h> 15 #include <__pstl/cpu_algos/cpu_traits.h> 16 #include <__type_traits/is_execution_policy.h> 17 #include <__utility/empty.h> 18 #include <optional> 19 20 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 21 # pragma GCC system_header 22 #endif 23 24 #if _LIBCPP_STD_VER >= 17 25 26 _LIBCPP_BEGIN_NAMESPACE_STD 27 namespace __pstl { 28 29 template <class _Backend, class _RawExecutionPolicy> 30 struct __cpu_parallel_stable_sort { 31 template <class _Policy, class _RandomAccessIterator, class _Comp> 32 _LIBCPP_HIDE_FROM_ABI optional<__empty> 33 operator()(_Policy&&, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) const noexcept { 34 if constexpr (__is_parallel_execution_policy_v<_RawExecutionPolicy>) { 35 return __cpu_traits<_Backend>::__stable_sort( 36 __first, __last, __comp, [](_RandomAccessIterator __g_first, _RandomAccessIterator __g_last, _Comp __g_comp) { 37 std::stable_sort(__g_first, __g_last, __g_comp); 38 }); 39 } else { 40 std::stable_sort(__first, __last, __comp); 41 return __empty{}; 42 } 43 } 44 }; 45 46 } // namespace __pstl 47 _LIBCPP_END_NAMESPACE_STD 48 49 #endif // _LIBCPP_STD_VER >= 17 50 51 #endif // _LIBCPP___PSTL_CPU_ALGOS_STABLE_SORT_H 52