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//===----------------------------------------------------------------------===//
//
// 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_SWAP_RANGES_H
#define _LIBCPP___ALGORITHM_SWAP_RANGES_H
#include <__algorithm/iterator_operations.h>
#include <__algorithm/min.h>
#include <__config>
#include <__fwd/bit_reference.h>
#include <__utility/move.h>
#include <__utility/pair.h>
#include <__utility/swap.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_PUSH_MACROS
#include <__undef_macros>
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _Cl, class _Cr>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cr, false> __swap_ranges_aligned(
__bit_iterator<_Cl, false> __first, __bit_iterator<_Cl, false> __last, __bit_iterator<_Cr, false> __result) {
using _I1 = __bit_iterator<_Cl, false>;
using difference_type = typename _I1::difference_type;
using __storage_type = typename _I1::__storage_type;
const int __bits_per_word = _I1::__bits_per_word;
difference_type __n = __last - __first;
if (__n > 0) {
// do first word
if (__first.__ctz_ != 0) {
unsigned __clz = __bits_per_word - __first.__ctz_;
difference_type __dn = std::min(static_cast<difference_type>(__clz), __n);
__n -= __dn;
__storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz - __dn));
__storage_type __b1 = *__first.__seg_ & __m;
*__first.__seg_ &= ~__m;
__storage_type __b2 = *__result.__seg_ & __m;
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b1;
*__first.__seg_ |= __b2;
__result.__seg_ += (__dn + __result.__ctz_) / __bits_per_word;
__result.__ctz_ = static_cast<unsigned>((__dn + __result.__ctz_) % __bits_per_word);
++__first.__seg_;
// __first.__ctz_ = 0;
}
// __first.__ctz_ == 0;
// do middle words
for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first.__seg_, ++__result.__seg_)
swap(*__first.__seg_, *__result.__seg_);
// do last word
if (__n > 0) {
__storage_type __m = ~__storage_type(0) >> (__bits_per_word - __n);
__storage_type __b1 = *__first.__seg_ & __m;
*__first.__seg_ &= ~__m;
__storage_type __b2 = *__result.__seg_ & __m;
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b1;
*__first.__seg_ |= __b2;
__result.__ctz_ = static_cast<unsigned>(__n);
}
}
return __result;
}
template <class _Cl, class _Cr>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 __bit_iterator<_Cr, false> __swap_ranges_unaligned(
__bit_iterator<_Cl, false> __first, __bit_iterator<_Cl, false> __last, __bit_iterator<_Cr, false> __result) {
using _I1 = __bit_iterator<_Cl, false>;
using difference_type = typename _I1::difference_type;
using __storage_type = typename _I1::__storage_type;
const int __bits_per_word = _I1::__bits_per_word;
difference_type __n = __last - __first;
if (__n > 0) {
// do first word
if (__first.__ctz_ != 0) {
unsigned __clz_f = __bits_per_word - __first.__ctz_;
difference_type __dn = std::min(static_cast<difference_type>(__clz_f), __n);
__n -= __dn;
__storage_type __m = (~__storage_type(0) << __first.__ctz_) & (~__storage_type(0) >> (__clz_f - __dn));
__storage_type __b1 = *__first.__seg_ & __m;
*__first.__seg_ &= ~__m;
unsigned __clz_r = __bits_per_word - __result.__ctz_;
__storage_type __ddn = std::min<__storage_type>(__dn, __clz_r);
__m = (~__storage_type(0) << __result.__ctz_) & (~__storage_type(0) >> (__clz_r - __ddn));
__storage_type __b2 = *__result.__seg_ & __m;
*__result.__seg_ &= ~__m;
if (__result.__ctz_ > __first.__ctz_) {
unsigned __s = __result.__ctz_ - __first.__ctz_;
*__result.__seg_ |= __b1 << __s;
*__first.__seg_ |= __b2 >> __s;
} else {
unsigned __s = __first.__ctz_ - __result.__ctz_;
*__result.__seg_ |= __b1 >> __s;
*__first.__seg_ |= __b2 << __s;
}
__result.__seg_ += (__ddn + __result.__ctz_) / __bits_per_word;
__result.__ctz_ = static_cast<unsigned>((__ddn + __result.__ctz_) % __bits_per_word);
__dn -= __ddn;
if (__dn > 0) {
__m = ~__storage_type(0) >> (__bits_per_word - __dn);
__b2 = *__result.__seg_ & __m;
*__result.__seg_ &= ~__m;
unsigned __s = __first.__ctz_ + __ddn;
*__result.__seg_ |= __b1 >> __s;
*__first.__seg_ |= __b2 << __s;
__result.__ctz_ = static_cast<unsigned>(__dn);
}
++__first.__seg_;
// __first.__ctz_ = 0;
}
// __first.__ctz_ == 0;
// do middle words
__storage_type __m = ~__storage_type(0) << __result.__ctz_;
unsigned __clz_r = __bits_per_word - __result.__ctz_;
for (; __n >= __bits_per_word; __n -= __bits_per_word, ++__first.__seg_) {
__storage_type __b1 = *__first.__seg_;
__storage_type __b2 = *__result.__seg_ & __m;
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b1 << __result.__ctz_;
*__first.__seg_ = __b2 >> __result.__ctz_;
++__result.__seg_;
__b2 = *__result.__seg_ & ~__m;
*__result.__seg_ &= __m;
*__result.__seg_ |= __b1 >> __clz_r;
*__first.__seg_ |= __b2 << __clz_r;
}
// do last word
if (__n > 0) {
__m = ~__storage_type(0) >> (__bits_per_word - __n);
__storage_type __b1 = *__first.__seg_ & __m;
*__first.__seg_ &= ~__m;
__storage_type __dn = std::min<__storage_type>(__n, __clz_r);
__m = (~__storage_type(0) << __result.__ctz_) & (~__storage_type(0) >> (__clz_r - __dn));
__storage_type __b2 = *__result.__seg_ & __m;
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b1 << __result.__ctz_;
*__first.__seg_ |= __b2 >> __result.__ctz_;
__result.__seg_ += (__dn + __result.__ctz_) / __bits_per_word;
__result.__ctz_ = static_cast<unsigned>((__dn + __result.__ctz_) % __bits_per_word);
__n -= __dn;
if (__n > 0) {
__m = ~__storage_type(0) >> (__bits_per_word - __n);
__b2 = *__result.__seg_ & __m;
*__result.__seg_ &= ~__m;
*__result.__seg_ |= __b1 >> __dn;
*__first.__seg_ |= __b2 << __dn;
__result.__ctz_ = static_cast<unsigned>(__n);
}
}
}
return __result;
}
// 2+1 iterators: size2 >= size1; used by std::swap_ranges.
template <class, class _Cl, class _Cr>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<__bit_iterator<_Cl, false>, __bit_iterator<_Cr, false> >
__swap_ranges(__bit_iterator<_Cl, false> __first1,
__bit_iterator<_Cl, false> __last1,
__bit_iterator<_Cr, false> __first2) {
if (__first1.__ctz_ == __first2.__ctz_)
return std::make_pair(__last1, std::__swap_ranges_aligned(__first1, __last1, __first2));
return std::make_pair(__last1, std::__swap_ranges_unaligned(__first1, __last1, __first2));
}
// 2+2 iterators: used by std::ranges::swap_ranges.
template <class _AlgPolicy, class _Cl, class _Cr>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<__bit_iterator<_Cl, false>, __bit_iterator<_Cr, false> >
__swap_ranges(__bit_iterator<_Cl, false> __first1,
__bit_iterator<_Cl, false> __last1,
__bit_iterator<_Cr, false> __first2,
__bit_iterator<_Cr, false> __last2) {
if (__last1 - __first1 < __last2 - __first2)
return std::make_pair(__last1, std::__swap_ranges<_AlgPolicy>(__first1, __last1, __first2).second);
return std::make_pair(std::__swap_ranges<_AlgPolicy>(__first2, __last2, __first1).second, __last2);
}
// 2+2 iterators: the shorter size will be used.
template <class _AlgPolicy, class _ForwardIterator1, class _Sentinel1, class _ForwardIterator2, class _Sentinel2>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator1, _ForwardIterator2>
__swap_ranges(_ForwardIterator1 __first1, _Sentinel1 __last1, _ForwardIterator2 __first2, _Sentinel2 __last2) {
while (__first1 != __last1 && __first2 != __last2) {
_IterOps<_AlgPolicy>::iter_swap(__first1, __first2);
++__first1;
++__first2;
}
return pair<_ForwardIterator1, _ForwardIterator2>(std::move(__first1), std::move(__first2));
}
// 2+1 iterators: size2 >= size1.
template <class _AlgPolicy, class _ForwardIterator1, class _Sentinel1, class _ForwardIterator2>
_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 pair<_ForwardIterator1, _ForwardIterator2>
__swap_ranges(_ForwardIterator1 __first1, _Sentinel1 __last1, _ForwardIterator2 __first2) {
while (__first1 != __last1) {
_IterOps<_AlgPolicy>::iter_swap(__first1, __first2);
++__first1;
++__first2;
}
return pair<_ForwardIterator1, _ForwardIterator2>(std::move(__first1), std::move(__first2));
}
template <class _ForwardIterator1, class _ForwardIterator2>
inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 _ForwardIterator2
swap_ranges(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2) {
return std::__swap_ranges<_ClassicAlgPolicy>(std::move(__first1), std::move(__last1), std::move(__first2)).second;
}
_LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
#endif // _LIBCPP___ALGORITHM_SWAP_RANGES_H
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