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authorDevtools Arcadia <arcadia-devtools@yandex-team.ru>2022-02-07 18:08:42 +0300
committerDevtools Arcadia <arcadia-devtools@mous.vla.yp-c.yandex.net>2022-02-07 18:08:42 +0300
commit1110808a9d39d4b808aef724c861a2e1a38d2a69 (patch)
treee26c9fed0de5d9873cce7e00bc214573dc2195b7 /contrib/libs/cxxsupp/libcxx/include/__algorithm/find_end.h
downloadydb-1110808a9d39d4b808aef724c861a2e1a38d2a69.tar.gz
intermediate changes
ref:cde9a383711a11544ce7e107a78147fb96cc4029
Diffstat (limited to 'contrib/libs/cxxsupp/libcxx/include/__algorithm/find_end.h')
-rw-r--r--contrib/libs/cxxsupp/libcxx/include/__algorithm/find_end.h148
1 files changed, 148 insertions, 0 deletions
diff --git a/contrib/libs/cxxsupp/libcxx/include/__algorithm/find_end.h b/contrib/libs/cxxsupp/libcxx/include/__algorithm/find_end.h
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index 00000000000..95ac2199fd3
--- /dev/null
+++ b/contrib/libs/cxxsupp/libcxx/include/__algorithm/find_end.h
@@ -0,0 +1,148 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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_FIND_END_OF_H
+#define _LIBCPP___ALGORITHM_FIND_END_OF_H
+
+#include <__config>
+#include <__algorithm/comp.h>
+#include <__iterator/iterator_traits.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _BinaryPredicate, class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1 __find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2, _ForwardIterator2 __last2,
+ _BinaryPredicate __pred, forward_iterator_tag,
+ forward_iterator_tag) {
+ // modeled after search algorithm
+ _ForwardIterator1 __r = __last1; // __last1 is the "default" answer
+ if (__first2 == __last2)
+ return __r;
+ while (true) {
+ while (true) {
+ if (__first1 == __last1) // if source exhausted return last correct answer
+ return __r; // (or __last1 if never found)
+ if (__pred(*__first1, *__first2))
+ break;
+ ++__first1;
+ }
+ // *__first1 matches *__first2, now match elements after here
+ _ForwardIterator1 __m1 = __first1;
+ _ForwardIterator2 __m2 = __first2;
+ while (true) {
+ if (++__m2 == __last2) { // Pattern exhaused, record answer and search for another one
+ __r = __first1;
+ ++__first1;
+ break;
+ }
+ if (++__m1 == __last1) // Source exhausted, return last answer
+ return __r;
+ if (!__pred(*__m1, *__m2)) // mismatch, restart with a new __first
+ {
+ ++__first1;
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _BinaryPredicate, class _BidirectionalIterator1, class _BidirectionalIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX17 _BidirectionalIterator1 __find_end(
+ _BidirectionalIterator1 __first1, _BidirectionalIterator1 __last1, _BidirectionalIterator2 __first2,
+ _BidirectionalIterator2 __last2, _BinaryPredicate __pred, bidirectional_iterator_tag, bidirectional_iterator_tag) {
+ // modeled after search algorithm (in reverse)
+ if (__first2 == __last2)
+ return __last1; // Everything matches an empty sequence
+ _BidirectionalIterator1 __l1 = __last1;
+ _BidirectionalIterator2 __l2 = __last2;
+ --__l2;
+ while (true) {
+ // Find last element in sequence 1 that matchs *(__last2-1), with a mininum of loop checks
+ while (true) {
+ if (__first1 == __l1) // return __last1 if no element matches *__first2
+ return __last1;
+ if (__pred(*--__l1, *__l2))
+ break;
+ }
+ // *__l1 matches *__l2, now match elements before here
+ _BidirectionalIterator1 __m1 = __l1;
+ _BidirectionalIterator2 __m2 = __l2;
+ while (true) {
+ if (__m2 == __first2) // If pattern exhausted, __m1 is the answer (works for 1 element pattern)
+ return __m1;
+ if (__m1 == __first1) // Otherwise if source exhaused, pattern not found
+ return __last1;
+ if (!__pred(*--__m1, *--__m2)) // if there is a mismatch, restart with a new __l1
+ {
+ break;
+ } // else there is a match, check next elements
+ }
+ }
+}
+
+template <class _BinaryPredicate, class _RandomAccessIterator1, class _RandomAccessIterator2>
+_LIBCPP_CONSTEXPR_AFTER_CXX11 _RandomAccessIterator1 __find_end(
+ _RandomAccessIterator1 __first1, _RandomAccessIterator1 __last1, _RandomAccessIterator2 __first2,
+ _RandomAccessIterator2 __last2, _BinaryPredicate __pred, random_access_iterator_tag, random_access_iterator_tag) {
+ // Take advantage of knowing source and pattern lengths. Stop short when source is smaller than pattern
+ typename iterator_traits<_RandomAccessIterator2>::difference_type __len2 = __last2 - __first2;
+ if (__len2 == 0)
+ return __last1;
+ typename iterator_traits<_RandomAccessIterator1>::difference_type __len1 = __last1 - __first1;
+ if (__len1 < __len2)
+ return __last1;
+ const _RandomAccessIterator1 __s = __first1 + (__len2 - 1); // End of pattern match can't go before here
+ _RandomAccessIterator1 __l1 = __last1;
+ _RandomAccessIterator2 __l2 = __last2;
+ --__l2;
+ while (true) {
+ while (true) {
+ if (__s == __l1)
+ return __last1;
+ if (__pred(*--__l1, *__l2))
+ break;
+ }
+ _RandomAccessIterator1 __m1 = __l1;
+ _RandomAccessIterator2 __m2 = __l2;
+ while (true) {
+ if (__m2 == __first2)
+ return __m1;
+ // no need to check range on __m1 because __s guarantees we have enough source
+ if (!__pred(*--__m1, *--__m2)) {
+ break;
+ }
+ }
+ }
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2, class _BinaryPredicate>
+_LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1
+find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _ForwardIterator2 __last2,
+ _BinaryPredicate __pred) {
+ return _VSTD::__find_end<_BinaryPredicate&>(
+ __first1, __last1, __first2, __last2, __pred, typename iterator_traits<_ForwardIterator1>::iterator_category(),
+ typename iterator_traits<_ForwardIterator2>::iterator_category());
+}
+
+template <class _ForwardIterator1, class _ForwardIterator2>
+_LIBCPP_NODISCARD_EXT inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17 _ForwardIterator1
+find_end(_ForwardIterator1 __first1, _ForwardIterator1 __last1, _ForwardIterator2 __first2, _ForwardIterator2 __last2) {
+ typedef typename iterator_traits<_ForwardIterator1>::value_type __v1;
+ typedef typename iterator_traits<_ForwardIterator2>::value_type __v2;
+ return _VSTD::find_end(__first1, __last1, __first2, __last2, __equal_to<__v1, __v2>());
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___ALGORITHM_FIND_END_OF_H