//===----------------------------------------------------------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// #ifndef _LIBCPP___ALGORITHM_SORT_H #define _LIBCPP___ALGORITHM_SORT_H #include <__algorithm/comp.h> #include <__algorithm/comp_ref_type.h> #include <__algorithm/min_element.h> #include <__algorithm/partial_sort.h> #include <__algorithm/unwrap_iter.h> #include <__bits> #include <__config> #include <__debug> #include <__functional/operations.h> #include <__utility/swap.h> #include #include #if defined(_LIBCPP_DEBUG_RANDOMIZE_UNSPECIFIED_STABILITY) # include <__algorithm/shuffle.h> #endif #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) # pragma GCC system_header #endif _LIBCPP_BEGIN_NAMESPACE_STD // stable, 2-3 compares, 0-2 swaps template _LIBCPP_CONSTEXPR_AFTER_CXX11 unsigned __sort3(_ForwardIterator __x, _ForwardIterator __y, _ForwardIterator __z, _Compare __c) { unsigned __r = 0; if (!__c(*__y, *__x)) // if x <= y { if (!__c(*__z, *__y)) // if y <= z return __r; // x <= y && y <= z // x <= y && y > z swap(*__y, *__z); // x <= z && y < z __r = 1; if (__c(*__y, *__x)) // if x > y { swap(*__x, *__y); // x < y && y <= z __r = 2; } return __r; // x <= y && y < z } if (__c(*__z, *__y)) // x > y, if y > z { swap(*__x, *__z); // x < y && y < z __r = 1; return __r; } swap(*__x, *__y); // x > y && y <= z __r = 1; // x < y && x <= z if (__c(*__z, *__y)) // if y > z { swap(*__y, *__z); // x <= y && y < z __r = 2; } return __r; } // x <= y && y <= z // stable, 3-6 compares, 0-5 swaps template unsigned __sort4(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3, _ForwardIterator __x4, _Compare __c) { unsigned __r = _VSTD::__sort3<_Compare>(__x1, __x2, __x3, __c); if (__c(*__x4, *__x3)) { swap(*__x3, *__x4); ++__r; if (__c(*__x3, *__x2)) { swap(*__x2, *__x3); ++__r; if (__c(*__x2, *__x1)) { swap(*__x1, *__x2); ++__r; } } } return __r; } // stable, 4-10 compares, 0-9 swaps template _LIBCPP_HIDDEN unsigned __sort5(_ForwardIterator __x1, _ForwardIterator __x2, _ForwardIterator __x3, _ForwardIterator __x4, _ForwardIterator __x5, _Compare __c) { unsigned __r = _VSTD::__sort4<_Compare>(__x1, __x2, __x3, __x4, __c); if (__c(*__x5, *__x4)) { swap(*__x4, *__x5); ++__r; if (__c(*__x4, *__x3)) { swap(*__x3, *__x4); ++__r; if (__c(*__x3, *__x2)) { swap(*__x2, *__x3); ++__r; if (__c(*__x2, *__x1)) { swap(*__x1, *__x2); ++__r; } } } } return __r; } template struct __is_simple_comparator : false_type {}; template struct __is_simple_comparator<__less<_Tp>&> : true_type {}; template struct __is_simple_comparator&> : true_type {}; template struct __is_simple_comparator&> : true_type {}; template ::value_type> using __use_branchless_sort = integral_constant::value && sizeof(_Tp) <= sizeof(void*) && is_arithmetic<_Tp>::value && __is_simple_comparator<_Compare>::value>; // Ensures that __c(*__x, *__y) is true by swapping *__x and *__y if necessary. template inline _LIBCPP_HIDE_FROM_ABI void __cond_swap(_RandomAccessIterator __x, _RandomAccessIterator __y, _Compare __c) { using value_type = typename iterator_traits<_RandomAccessIterator>::value_type; bool __r = __c(*__x, *__y); value_type __tmp = __r ? *__x : *__y; *__y = __r ? *__y : *__x; *__x = __tmp; } // Ensures that *__x, *__y and *__z are ordered according to the comparator __c, // under the assumption that *__y and *__z are already ordered. template inline _LIBCPP_HIDE_FROM_ABI void __partially_sorted_swap(_RandomAccessIterator __x, _RandomAccessIterator __y, _RandomAccessIterator __z, _Compare __c) { using value_type = typename iterator_traits<_RandomAccessIterator>::value_type; bool __r = __c(*__z, *__x); value_type __tmp = __r ? *__z : *__x; *__z = __r ? *__x : *__z; __r = __c(__tmp, *__y); *__x = __r ? *__x : *__y; *__y = __r ? *__y : __tmp; } template inline _LIBCPP_HIDE_FROM_ABI __enable_if_t<__use_branchless_sort<_Compare, _RandomAccessIterator>::value, void> __sort3_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _Compare __c) { _VSTD::__cond_swap<_Compare>(__x2, __x3, __c); _VSTD::__partially_sorted_swap<_Compare>(__x1, __x2, __x3, __c); } template inline _LIBCPP_HIDE_FROM_ABI __enable_if_t::value, void> __sort3_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _Compare __c) { _VSTD::__sort3<_Compare>(__x1, __x2, __x3, __c); } template inline _LIBCPP_HIDE_FROM_ABI __enable_if_t<__use_branchless_sort<_Compare, _RandomAccessIterator>::value, void> __sort4_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _RandomAccessIterator __x4, _Compare __c) { _VSTD::__cond_swap<_Compare>(__x1, __x3, __c); _VSTD::__cond_swap<_Compare>(__x2, __x4, __c); _VSTD::__cond_swap<_Compare>(__x1, __x2, __c); _VSTD::__cond_swap<_Compare>(__x3, __x4, __c); _VSTD::__cond_swap<_Compare>(__x2, __x3, __c); } template inline _LIBCPP_HIDE_FROM_ABI __enable_if_t::value, void> __sort4_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _RandomAccessIterator __x4, _Compare __c) { _VSTD::__sort4<_Compare>(__x1, __x2, __x3, __x4, __c); } template inline _LIBCPP_HIDE_FROM_ABI __enable_if_t<__use_branchless_sort<_Compare, _RandomAccessIterator>::value, void> __sort5_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _RandomAccessIterator __x4, _RandomAccessIterator __x5, _Compare __c) { _VSTD::__cond_swap<_Compare>(__x1, __x2, __c); _VSTD::__cond_swap<_Compare>(__x4, __x5, __c); _VSTD::__partially_sorted_swap<_Compare>(__x3, __x4, __x5, __c); _VSTD::__cond_swap<_Compare>(__x2, __x5, __c); _VSTD::__partially_sorted_swap<_Compare>(__x1, __x3, __x4, __c); _VSTD::__partially_sorted_swap<_Compare>(__x2, __x3, __x4, __c); } template inline _LIBCPP_HIDE_FROM_ABI __enable_if_t::value, void> __sort5_maybe_branchless(_RandomAccessIterator __x1, _RandomAccessIterator __x2, _RandomAccessIterator __x3, _RandomAccessIterator __x4, _RandomAccessIterator __x5, _Compare __c) { _VSTD::__sort5<_Compare>(__x1, __x2, __x3, __x4, __x5, __c); } // Assumes size > 0 template _LIBCPP_CONSTEXPR_AFTER_CXX11 void __selection_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp) { _BidirectionalIterator __lm1 = __last; for (--__lm1; __first != __lm1; ++__first) { _BidirectionalIterator __i = _VSTD::min_element(__first, __last, __comp); if (__i != __first) swap(*__first, *__i); } } template void __insertion_sort(_BidirectionalIterator __first, _BidirectionalIterator __last, _Compare __comp) { typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type; if (__first != __last) { _BidirectionalIterator __i = __first; for (++__i; __i != __last; ++__i) { _BidirectionalIterator __j = __i; value_type __t(_VSTD::move(*__j)); for (_BidirectionalIterator __k = __i; __k != __first && __comp(__t, *--__k); --__j) *__j = _VSTD::move(*__k); *__j = _VSTD::move(__t); } } } template void __insertion_sort_3(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) { typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type; typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type; _RandomAccessIterator __j = __first + difference_type(2); _VSTD::__sort3_maybe_branchless<_Compare>(__first, __first + difference_type(1), __j, __comp); for (_RandomAccessIterator __i = __j + difference_type(1); __i != __last; ++__i) { if (__comp(*__i, *__j)) { value_type __t(_VSTD::move(*__i)); _RandomAccessIterator __k = __j; __j = __i; do { *__j = _VSTD::move(*__k); __j = __k; } while (__j != __first && __comp(__t, *--__k)); *__j = _VSTD::move(__t); } __j = __i; } } template bool __insertion_sort_incomplete(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) { typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type; switch (__last - __first) { case 0: case 1: return true; case 2: if (__comp(*--__last, *__first)) swap(*__first, *__last); return true; case 3: _VSTD::__sort3_maybe_branchless<_Compare>(__first, __first + difference_type(1), --__last, __comp); return true; case 4: _VSTD::__sort4_maybe_branchless<_Compare>(__first, __first + difference_type(1), __first + difference_type(2), --__last, __comp); return true; case 5: _VSTD::__sort5_maybe_branchless<_Compare>(__first, __first + difference_type(1), __first + difference_type(2), __first + difference_type(3), --__last, __comp); return true; } typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type; _RandomAccessIterator __j = __first + difference_type(2); _VSTD::__sort3_maybe_branchless<_Compare>(__first, __first + difference_type(1), __j, __comp); const unsigned __limit = 8; unsigned __count = 0; for (_RandomAccessIterator __i = __j + difference_type(1); __i != __last; ++__i) { if (__comp(*__i, *__j)) { value_type __t(_VSTD::move(*__i)); _RandomAccessIterator __k = __j; __j = __i; do { *__j = _VSTD::move(*__k); __j = __k; } while (__j != __first && __comp(__t, *--__k)); *__j = _VSTD::move(__t); if (++__count == __limit) return ++__i == __last; } __j = __i; } return true; } template void __insertion_sort_move(_BidirectionalIterator __first1, _BidirectionalIterator __last1, typename iterator_traits<_BidirectionalIterator>::value_type* __first2, _Compare __comp) { typedef typename iterator_traits<_BidirectionalIterator>::value_type value_type; if (__first1 != __last1) { __destruct_n __d(0); unique_ptr __h(__first2, __d); value_type* __last2 = __first2; ::new ((void*)__last2) value_type(_VSTD::move(*__first1)); __d.template __incr(); for (++__last2; ++__first1 != __last1; ++__last2) { value_type* __j2 = __last2; value_type* __i2 = __j2; if (__comp(*__first1, *--__i2)) { ::new ((void*)__j2) value_type(_VSTD::move(*__i2)); __d.template __incr(); for (--__j2; __i2 != __first2 && __comp(*__first1, *--__i2); --__j2) *__j2 = _VSTD::move(*__i2); *__j2 = _VSTD::move(*__first1); } else { ::new ((void*)__j2) value_type(_VSTD::move(*__first1)); __d.template __incr(); } } __h.release(); } } template void __introsort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp, typename iterator_traits<_RandomAccessIterator>::difference_type __depth) { typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type; typedef typename iterator_traits<_RandomAccessIterator>::value_type value_type; const difference_type __limit = is_trivially_copy_constructible::value && is_trivially_copy_assignable::value ? 30 : 6; while (true) { __restart: difference_type __len = __last - __first; switch (__len) { case 0: case 1: return; case 2: if (__comp(*--__last, *__first)) swap(*__first, *__last); return; case 3: _VSTD::__sort3_maybe_branchless<_Compare>(__first, __first + difference_type(1), --__last, __comp); return; case 4: _VSTD::__sort4_maybe_branchless<_Compare>(__first, __first + difference_type(1), __first + difference_type(2), --__last, __comp); return; case 5: _VSTD::__sort5_maybe_branchless<_Compare>(__first, __first + difference_type(1), __first + difference_type(2), __first + difference_type(3), --__last, __comp); return; } if (__len <= __limit) { _VSTD::__insertion_sort_3<_Compare>(__first, __last, __comp); return; } // __len > 5 if (__depth == 0) { // Fallback to heap sort as Introsort suggests. _VSTD::__partial_sort<_Compare>(__first, __last, __last, __comp); return; } --__depth; _RandomAccessIterator __m = __first; _RandomAccessIterator __lm1 = __last; --__lm1; unsigned __n_swaps; { difference_type __delta; if (__len >= 1000) { __delta = __len / 2; __m += __delta; __delta /= 2; __n_swaps = _VSTD::__sort5<_Compare>(__first, __first + __delta, __m, __m + __delta, __lm1, __comp); } else { __delta = __len / 2; __m += __delta; __n_swaps = _VSTD::__sort3<_Compare>(__first, __m, __lm1, __comp); } } // *__m is median // partition [__first, __m) < *__m and *__m <= [__m, __last) // (this inhibits tossing elements equivalent to __m around unnecessarily) _RandomAccessIterator __i = __first; _RandomAccessIterator __j = __lm1; // j points beyond range to be tested, *__m is known to be <= *__lm1 // The search going up is known to be guarded but the search coming down isn't. // Prime the downward search with a guard. if (!__comp(*__i, *__m)) // if *__first == *__m { // *__first == *__m, *__first doesn't go in first part // manually guard downward moving __j against __i while (true) { if (__i == --__j) { // *__first == *__m, *__m <= all other elements // Parition instead into [__first, __i) == *__first and *__first < [__i, __last) ++__i; // __first + 1 __j = __last; if (!__comp(*__first, *--__j)) // we need a guard if *__first == *(__last-1) { while (true) { if (__i == __j) return; // [__first, __last) all equivalent elements if (__comp(*__first, *__i)) { swap(*__i, *__j); ++__n_swaps; ++__i; break; } ++__i; } } // [__first, __i) == *__first and *__first < [__j, __last) and __j == __last - 1 if (__i == __j) return; while (true) { while (!__comp(*__first, *__i)) ++__i; while (__comp(*__first, *--__j)) ; if (__i >= __j) break; swap(*__i, *__j); ++__n_swaps; ++__i; } // [__first, __i) == *__first and *__first < [__i, __last) // The first part is sorted, sort the second part // _VSTD::__sort<_Compare>(__i, __last, __comp); __first = __i; goto __restart; } if (__comp(*__j, *__m)) { swap(*__i, *__j); ++__n_swaps; break; // found guard for downward moving __j, now use unguarded partition } } } // It is known that *__i < *__m ++__i; // j points beyond range to be tested, *__m is known to be <= *__lm1 // if not yet partitioned... if (__i < __j) { // known that *(__i - 1) < *__m // known that __i <= __m while (true) { // __m still guards upward moving __i while (__comp(*__i, *__m)) ++__i; // It is now known that a guard exists for downward moving __j while (!__comp(*--__j, *__m)) ; if (__i > __j) break; swap(*__i, *__j); ++__n_swaps; // It is known that __m != __j // If __m just moved, follow it if (__m == __i) __m = __j; ++__i; } } // [__first, __i) < *__m and *__m <= [__i, __last) if (__i != __m && __comp(*__m, *__i)) { swap(*__i, *__m); ++__n_swaps; } // [__first, __i) < *__i and *__i <= [__i+1, __last) // If we were given a perfect partition, see if insertion sort is quick... if (__n_swaps == 0) { bool __fs = _VSTD::__insertion_sort_incomplete<_Compare>(__first, __i, __comp); if (_VSTD::__insertion_sort_incomplete<_Compare>(__i + difference_type(1), __last, __comp)) { if (__fs) return; __last = __i; continue; } else { if (__fs) { __first = ++__i; continue; } } } // sort smaller range with recursive call and larger with tail recursion elimination if (__i - __first < __last - __i) { _VSTD::__introsort<_Compare>(__first, __i, __comp, __depth); __first = ++__i; } else { _VSTD::__introsort<_Compare>(__i + difference_type(1), __last, __comp, __depth); __last = __i; } } } template inline _LIBCPP_HIDE_FROM_ABI _Number __log2i(_Number __n) { if (__n == 0) return 0; if (sizeof(__n) <= sizeof(unsigned)) return sizeof(unsigned) * CHAR_BIT - 1 - __libcpp_clz(static_cast(__n)); if (sizeof(__n) <= sizeof(unsigned long)) return sizeof(unsigned long) * CHAR_BIT - 1 - __libcpp_clz(static_cast(__n)); if (sizeof(__n) <= sizeof(unsigned long long)) return sizeof(unsigned long long) * CHAR_BIT - 1 - __libcpp_clz(static_cast(__n)); _Number __log2 = 0; while (__n > 1) { __log2++; __n >>= 1; } return __log2; } template void __sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) { typedef typename iterator_traits<_RandomAccessIterator>::difference_type difference_type; difference_type __depth_limit = 2 * __log2i(__last - __first); _VSTD::__introsort<_Compare>(__first, __last, __comp, __depth_limit); } template inline _LIBCPP_INLINE_VISIBILITY void __sort(_Tp** __first, _Tp** __last, __less<_Tp*>&) { __less __comp; _VSTD::__sort<__less&, uintptr_t*>((uintptr_t*)__first, (uintptr_t*)__last, __comp); } _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, char*>(char*, char*, __less&)) #ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, wchar_t*>(wchar_t*, wchar_t*, __less&)) #endif _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, signed char*>(signed char*, signed char*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, unsigned char*>(unsigned char*, unsigned char*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, short*>(short*, short*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, unsigned short*>(unsigned short*, unsigned short*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, int*>(int*, int*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, unsigned*>(unsigned*, unsigned*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, long*>(long*, long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, unsigned long*>(unsigned long*, unsigned long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, long long*>(long long*, long long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, unsigned long long*>(unsigned long long*, unsigned long long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, float*>(float*, float*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, double*>(double*, double*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS void __sort<__less&, long double*>(long double*, long double*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, char*>(char*, char*, __less&)) #ifndef _LIBCPP_HAS_NO_WIDE_CHARACTERS _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, wchar_t*>(wchar_t*, wchar_t*, __less&)) #endif _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, signed char*>(signed char*, signed char*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, unsigned char*>(unsigned char*, unsigned char*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, short*>(short*, short*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, unsigned short*>(unsigned short*, unsigned short*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, int*>(int*, int*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, unsigned*>(unsigned*, unsigned*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, long*>(long*, long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, unsigned long*>(unsigned long*, unsigned long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, long long*>(long long*, long long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, unsigned long long*>(unsigned long long*, unsigned long long*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, float*>(float*, float*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, double*>(double*, double*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS bool __insertion_sort_incomplete<__less&, long double*>(long double*, long double*, __less&)) _LIBCPP_EXTERN_TEMPLATE(_LIBCPP_FUNC_VIS unsigned __sort5<__less&, long double*>(long double*, long double*, long double*, long double*, long double*, __less&)) template inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 void sort(_RandomAccessIterator __first, _RandomAccessIterator __last, _Compare __comp) { _LIBCPP_DEBUG_RANDOMIZE_RANGE(__first, __last); typedef typename __comp_ref_type<_Compare>::type _Comp_ref; if (__libcpp_is_constant_evaluated()) { _VSTD::__partial_sort<_Comp_ref>(__first, __last, __last, _Comp_ref(__comp)); } else { _VSTD::__sort<_Comp_ref>(_VSTD::__unwrap_iter(__first), _VSTD::__unwrap_iter(__last), _Comp_ref(__comp)); } } template inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 void sort(_RandomAccessIterator __first, _RandomAccessIterator __last) { _VSTD::sort(__first, __last, __less::value_type>()); } _LIBCPP_END_NAMESPACE_STD #endif // _LIBCPP___ALGORITHM_SORT_H