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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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef _LIBCPP___ALGORITHM_FILL_N_H10#define _LIBCPP___ALGORITHM_FILL_N_H11 12#include <__algorithm/for_each_n_segment.h>13#include <__algorithm/specialized_algorithms.h>14#include <__config>15#include <__iterator/iterator_traits.h>16#include <__iterator/segmented_iterator.h>17#include <__type_traits/enable_if.h>18#include <__utility/convert_to_integral.h>19#include <__utility/move.h>20 21#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)22# pragma GCC system_header23#endif24 25_LIBCPP_PUSH_MACROS26#include <__undef_macros>27 28_LIBCPP_BEGIN_NAMESPACE_STD29 30// fill_n isn't specialized for std::memset, because the compiler already optimizes the loop to a call to std::memset.31 32template <33 class _OutputIterator,34 class _Size,35 class _Tp,36 __enable_if_t<!__specialized_algorithm<_Algorithm::__fill_n, __single_iterator<_OutputIterator> >::__has_algorithm,37 int> = 0>38inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator39__fill_n(_OutputIterator __first, _Size __n, const _Tp& __value) {40#ifndef _LIBCPP_CXX03_LANG41 if constexpr (__is_segmented_iterator_v<_OutputIterator>) {42 using __local_iterator = typename __segmented_iterator_traits<_OutputIterator>::__local_iterator;43 if constexpr (__has_random_access_iterator_category<__local_iterator>::value) {44 return std::__for_each_n_segment(__first, __n, [&](__local_iterator __lfirst, __local_iterator __llast) {45 std::__fill_n(__lfirst, __llast - __lfirst, __value);46 });47 }48 }49#endif50 for (; __n > 0; ++__first, (void)--__n)51 *__first = __value;52 return __first;53}54 55template <class _OutIter,56 class _Size,57 class _Tp,58 __enable_if_t<__specialized_algorithm<_Algorithm::__fill_n, __single_iterator<_OutIter> >::__has_algorithm,59 int> = 0>60_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutIter __fill_n(_OutIter __first, _Size __n, const _Tp& __value) {61 return __specialized_algorithm<_Algorithm::__fill_n, __single_iterator<_OutIter> >()(62 std::move(__first), __n, __value);63}64 65template <class _OutputIterator, class _Size, class _Tp>66inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator67fill_n(_OutputIterator __first, _Size __n, const _Tp& __value) {68 return std::__fill_n(__first, std::__convert_to_integral(__n), __value);69}70 71_LIBCPP_END_NAMESPACE_STD72 73_LIBCPP_POP_MACROS74 75#endif // _LIBCPP___ALGORITHM_FILL_N_H76