| //===----------------------------------------------------------------------===// |
| // |
| // 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_FILL_N_H |
| #define _LIBCPP___ALGORITHM_FILL_N_H |
| |
| #include <__algorithm/min.h> |
| #include <__config> |
| #include <__fwd/bit_reference.h> |
| #include <__iterator/iterator_traits.h> |
| #include <__memory/pointer_traits.h> |
| #include <__utility/convert_to_integral.h> |
| |
| #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| # pragma GCC system_header |
| #endif |
| |
| _LIBCPP_PUSH_MACROS |
| #include <__undef_macros> |
| |
| _LIBCPP_BEGIN_NAMESPACE_STD |
| |
| // fill_n isn't specialized for std::memset, because the compiler already optimizes the loop to a call to std::memset. |
| |
| template <class _OutputIterator, class _Size, class _Tp> |
| inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator |
| __fill_n(_OutputIterator __first, _Size __n, const _Tp& __value); |
| |
| template <bool _FillVal, class _Cp> |
| _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI void |
| __fill_n_bool(__bit_iterator<_Cp, false> __first, typename _Cp::size_type __n) { |
| using _It = __bit_iterator<_Cp, false>; |
| using __storage_type = typename _It::__storage_type; |
| |
| const int __bits_per_word = _It::__bits_per_word; |
| // do first partial word |
| if (__first.__ctz_ != 0) { |
| __storage_type __clz_f = static_cast<__storage_type>(__bits_per_word - __first.__ctz_); |
| __storage_type __dn = std::min(__clz_f, __n); |
| __storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn)); |
| if (_FillVal) |
| *__first.__seg_ |= __m; |
| else |
| *__first.__seg_ &= ~__m; |
| __n -= __dn; |
| ++__first.__seg_; |
| } |
| // do middle whole words |
| __storage_type __nw = __n / __bits_per_word; |
| std::__fill_n(std::__to_address(__first.__seg_), __nw, _FillVal ? static_cast<__storage_type>(-1) : 0); |
| __n -= __nw * __bits_per_word; |
| // do last partial word |
| if (__n > 0) { |
| __first.__seg_ += __nw; |
| __storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n); |
| if (_FillVal) |
| *__first.__seg_ |= __m; |
| else |
| *__first.__seg_ &= ~__m; |
| } |
| } |
| |
| template <class _Cp, class _Size> |
| inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cp, false> |
| __fill_n(__bit_iterator<_Cp, false> __first, _Size __n, const bool& __value) { |
| if (__n > 0) { |
| if (__value) |
| std::__fill_n_bool<true>(__first, __n); |
| else |
| std::__fill_n_bool<false>(__first, __n); |
| } |
| return __first + __n; |
| } |
| |
| template <class _OutputIterator, class _Size, class _Tp> |
| inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator |
| __fill_n(_OutputIterator __first, _Size __n, const _Tp& __value) { |
| for (; __n > 0; ++__first, (void)--__n) |
| *__first = __value; |
| return __first; |
| } |
| |
| template <class _OutputIterator, class _Size, class _Tp> |
| inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _OutputIterator |
| fill_n(_OutputIterator __first, _Size __n, const _Tp& __value) { |
| return std::__fill_n(__first, std::__convert_to_integral(__n), __value); |
| } |
| |
| _LIBCPP_END_NAMESPACE_STD |
| |
| _LIBCPP_POP_MACROS |
| |
| #endif // _LIBCPP___ALGORITHM_FILL_N_H |