gcc/libstdc++-v3/include/experimental/functional
Jonathan Wakely 32489ab56a PR libstdc++/83607 specialize Boyer-Moore searchers for std::byte
PR libstdc++/83607
	* include/std/functional (__is_byte_like): New trait.
	(__is_std_equal_to): Remove.
	(__boyer_moore_base_t): Use __is_byte_like instead of
	__is_std_equal_to.
	* include/experimental/functional (__is_std_equal_to): Remove.
	(__boyer_moore_base_t): Use __is_byte_like instead of
	__is_std_equal_to.
	* testsuite/20_util/function_objects/83607.cc: New test.

From-SVN: r256231
2018-01-04 10:21:29 +00:00

385 lines
12 KiB
C++

// <experimental/functional> -*- C++ -*-
// Copyright (C) 2014-2018 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file experimental/functional
* This is a TS C++ Library header.
*/
#ifndef _GLIBCXX_EXPERIMENTAL_FUNCTIONAL
#define _GLIBCXX_EXPERIMENTAL_FUNCTIONAL 1
#pragma GCC system_header
#if __cplusplus >= 201402L
#include <functional>
#include <tuple>
#include <iterator>
#include <unordered_map>
#include <vector>
#include <array>
#include <bits/stl_algo.h>
#ifdef _GLIBCXX_PARALLEL
# include <parallel/algorithm> // For std::__parallel::search
#endif
#include <experimental/bits/lfts_config.h>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
namespace experimental
{
inline namespace fundamentals_v1
{
// See C++14 §20.9.9, Function object binders
/// Variable template for std::is_bind_expression
template<typename _Tp>
constexpr bool is_bind_expression_v = std::is_bind_expression<_Tp>::value;
/// Variable template for std::is_placeholder
template<typename _Tp>
constexpr int is_placeholder_v = std::is_placeholder<_Tp>::value;
#define __cpp_lib_experimental_boyer_moore_searching 201411
// Searchers
template<typename _ForwardIterator1, typename _BinaryPredicate = equal_to<>>
class default_searcher
{
public:
default_searcher(_ForwardIterator1 __pat_first,
_ForwardIterator1 __pat_last,
_BinaryPredicate __pred = _BinaryPredicate())
: _M_m(__pat_first, __pat_last, std::move(__pred))
{ }
template<typename _ForwardIterator2>
_ForwardIterator2
operator()(_ForwardIterator2 __first, _ForwardIterator2 __last) const
{
return std::search(__first, __last,
std::get<0>(_M_m), std::get<1>(_M_m),
std::get<2>(_M_m));
}
private:
std::tuple<_ForwardIterator1, _ForwardIterator1, _BinaryPredicate> _M_m;
};
template<typename _Key, typename _Tp, typename _Hash, typename _Pred>
struct __boyer_moore_map_base
{
template<typename _RAIter>
__boyer_moore_map_base(_RAIter __pat, size_t __patlen,
_Hash&& __hf, _Pred&& __pred)
: _M_bad_char{ __patlen, std::move(__hf), std::move(__pred) }
{
if (__patlen > 0)
for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
_M_bad_char[__pat[__i]] = __patlen - 1 - __i;
}
using __diff_type = _Tp;
__diff_type
_M_lookup(_Key __key, __diff_type __not_found) const
{
auto __iter = _M_bad_char.find(__key);
if (__iter == _M_bad_char.end())
return __not_found;
return __iter->second;
}
_Pred
_M_pred() const { return _M_bad_char.key_eq(); }
_GLIBCXX_STD_C::unordered_map<_Key, _Tp, _Hash, _Pred> _M_bad_char;
};
template<typename _Tp, size_t _Len, typename _Pred>
struct __boyer_moore_array_base
{
template<typename _RAIter, typename _Unused>
__boyer_moore_array_base(_RAIter __pat, size_t __patlen,
_Unused&&, _Pred&& __pred)
: _M_bad_char{ _GLIBCXX_STD_C::array<_Tp, _Len>{}, std::move(__pred) }
{
std::get<0>(_M_bad_char).fill(__patlen);
if (__patlen > 0)
for (__diff_type __i = 0; __i < __patlen - 1; ++__i)
{
auto __ch = __pat[__i];
using _UCh = std::make_unsigned_t<decltype(__ch)>;
auto __uch = static_cast<_UCh>(__ch);
std::get<0>(_M_bad_char)[__uch] = __patlen - 1 - __i;
}
}
using __diff_type = _Tp;
template<typename _Key>
__diff_type
_M_lookup(_Key __key, __diff_type __not_found) const
{
auto __ukey = static_cast<std::make_unsigned_t<_Key>>(__key);
if (__ukey >= _Len)
return __not_found;
return std::get<0>(_M_bad_char)[__ukey];
}
const _Pred&
_M_pred() const { return std::get<1>(_M_bad_char); }
std::tuple<_GLIBCXX_STD_C::array<_Tp, _Len>, _Pred> _M_bad_char;
};
// Use __boyer_moore_array_base when pattern consists of narrow characters
// (or std::byte) and uses std::equal_to as the predicate.
template<typename _RAIter, typename _Hash, typename _Pred,
typename _Val = typename iterator_traits<_RAIter>::value_type,
typename _Diff = typename iterator_traits<_RAIter>::difference_type>
using __boyer_moore_base_t
= std::conditional_t<std::__is_byte_like<_Val, _Pred>::value,
__boyer_moore_array_base<_Diff, 256, _Pred>,
__boyer_moore_map_base<_Val, _Diff, _Hash, _Pred>>;
template<typename _RAIter, typename _Hash
= std::hash<typename std::iterator_traits<_RAIter>::value_type>,
typename _BinaryPredicate = std::equal_to<>>
class boyer_moore_searcher
: __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
{
using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
using typename _Base::__diff_type;
public:
boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
_Hash __hf = _Hash(),
_BinaryPredicate __pred = _BinaryPredicate());
template<typename _RandomAccessIterator2>
_RandomAccessIterator2
operator()(_RandomAccessIterator2 __first,
_RandomAccessIterator2 __last) const;
private:
bool
_M_is_prefix(_RAIter __word, __diff_type __len,
__diff_type __pos)
{
const auto& __pred = this->_M_pred();
__diff_type __suffixlen = __len - __pos;
for (__diff_type __i = 0; __i < __suffixlen; ++__i)
if (!__pred(__word[__i], __word[__pos + __i]))
return false;
return true;
}
__diff_type
_M_suffix_length(_RAIter __word, __diff_type __len,
__diff_type __pos)
{
const auto& __pred = this->_M_pred();
__diff_type __i = 0;
while (__pred(__word[__pos - __i], __word[__len - 1 - __i])
&& __i < __pos)
{
++__i;
}
return __i;
}
template<typename _Tp>
__diff_type
_M_bad_char_shift(_Tp __c) const
{ return this->_M_lookup(__c, _M_pat_end - _M_pat); }
_RAIter _M_pat;
_RAIter _M_pat_end;
_GLIBCXX_STD_C::vector<__diff_type> _M_good_suffix;
};
template<typename _RAIter, typename _Hash
= std::hash<typename std::iterator_traits<_RAIter>::value_type>,
typename _BinaryPredicate = std::equal_to<>>
class boyer_moore_horspool_searcher
: __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>
{
using _Base = __boyer_moore_base_t<_RAIter, _Hash, _BinaryPredicate>;
using typename _Base::__diff_type;
public:
boyer_moore_horspool_searcher(_RAIter __pat,
_RAIter __pat_end,
_Hash __hf = _Hash(),
_BinaryPredicate __pred
= _BinaryPredicate())
: _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
_M_pat(__pat), _M_pat_end(__pat_end)
{ }
template<typename _RandomAccessIterator2>
_RandomAccessIterator2
operator()(_RandomAccessIterator2 __first,
_RandomAccessIterator2 __last) const
{
const auto& __pred = this->_M_pred();
auto __patlen = _M_pat_end - _M_pat;
if (__patlen == 0)
return __first;
auto __len = __last - __first;
while (__len >= __patlen)
{
for (auto __scan = __patlen - 1;
__pred(__first[__scan], _M_pat[__scan]); --__scan)
if (__scan == 0)
return __first;
auto __shift = _M_bad_char_shift(__first[__patlen - 1]);
__len -= __shift;
__first += __shift;
}
return __last;
}
private:
template<typename _Tp>
__diff_type
_M_bad_char_shift(_Tp __c) const
{ return this->_M_lookup(__c, _M_pat_end - _M_pat); }
_RAIter _M_pat;
_RAIter _M_pat_end;
};
/// Generator function for default_searcher
template<typename _ForwardIterator,
typename _BinaryPredicate = std::equal_to<>>
inline default_searcher<_ForwardIterator, _BinaryPredicate>
make_default_searcher(_ForwardIterator __pat_first,
_ForwardIterator __pat_last,
_BinaryPredicate __pred = _BinaryPredicate())
{ return { __pat_first, __pat_last, __pred }; }
/// Generator function for boyer_moore_searcher
template<typename _RAIter, typename _Hash
= std::hash<typename std::iterator_traits<_RAIter>::value_type>,
typename _BinaryPredicate = equal_to<>>
inline boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>
make_boyer_moore_searcher(_RAIter __pat_first, _RAIter __pat_last,
_Hash __hf = _Hash(),
_BinaryPredicate __pred = _BinaryPredicate())
{ return { __pat_first, __pat_last, std::move(__hf), std::move(__pred) }; }
/// Generator function for boyer_moore_horspool_searcher
template<typename _RAIter, typename _Hash
= std::hash<typename std::iterator_traits<_RAIter>::value_type>,
typename _BinaryPredicate = equal_to<>>
inline boyer_moore_horspool_searcher<_RAIter, _Hash, _BinaryPredicate>
make_boyer_moore_horspool_searcher(_RAIter __pat_first, _RAIter __pat_last,
_Hash __hf = _Hash(),
_BinaryPredicate __pred
= _BinaryPredicate())
{ return { __pat_first, __pat_last, std::move(__hf), std::move(__pred) }; }
template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
boyer_moore_searcher(_RAIter __pat, _RAIter __pat_end,
_Hash __hf, _BinaryPredicate __pred)
: _Base(__pat, __pat_end - __pat, std::move(__hf), std::move(__pred)),
_M_pat(__pat), _M_pat_end(__pat_end), _M_good_suffix(__pat_end - __pat)
{
auto __patlen = __pat_end - __pat;
if (__patlen == 0)
return;
__diff_type __last_prefix = __patlen - 1;
for (__diff_type __p = __patlen - 1; __p >= 0; --__p)
{
if (_M_is_prefix(__pat, __patlen, __p + 1))
__last_prefix = __p + 1;
_M_good_suffix[__p] = __last_prefix + (__patlen - 1 - __p);
}
for (__diff_type __p = 0; __p < __patlen - 1; ++__p)
{
auto __slen = _M_suffix_length(__pat, __patlen, __p);
auto __pos = __patlen - 1 - __slen;
if (!__pred(__pat[__p - __slen], __pat[__pos]))
_M_good_suffix[__pos] = __patlen - 1 - __p + __slen;
}
}
template<typename _RAIter, typename _Hash, typename _BinaryPredicate>
template<typename _RandomAccessIterator2>
_RandomAccessIterator2
boyer_moore_searcher<_RAIter, _Hash, _BinaryPredicate>::
operator()(_RandomAccessIterator2 __first,
_RandomAccessIterator2 __last) const
{
auto __patlen = _M_pat_end - _M_pat;
if (__patlen == 0)
return __first;
const auto& __pred = this->_M_pred();
__diff_type __i = __patlen - 1;
auto __stringlen = __last - __first;
while (__i < __stringlen)
{
__diff_type __j = __patlen - 1;
while (__j >= 0 && __pred(__first[__i], _M_pat[__j]))
{
--__i;
--__j;
}
if (__j < 0)
return __first + __i + 1;
__i += std::max(_M_bad_char_shift(__first[__i]),
_M_good_suffix[__j]);
}
return __last;
}
} // namespace fundamentals_v1
inline namespace fundamentals_v2
{
#define __cpp_lib_experimental_not_fn 201406
/// [func.not_fn] Function template not_fn
template<typename _Fn>
inline auto
not_fn(_Fn&& __fn)
noexcept(std::is_nothrow_constructible<std::decay_t<_Fn>, _Fn&&>::value)
{
return std::_Not_fn<std::decay_t<_Fn>>{std::forward<_Fn>(__fn), 0};
}
} // namespace fundamentals_v2
} // namespace experimental
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace std
#endif // C++14
#endif // _GLIBCXX_EXPERIMENTAL_FUNCTIONAL