Dan Albert | 287553d | 2017-02-16 10:47:51 -0800 | [diff] [blame] | 1 | // -*- C++ -*- |
| 2 | //===-------------------------- functional --------------------------------===// |
| 3 | // |
| 4 | // The LLVM Compiler Infrastructure |
| 5 | // |
| 6 | // This file is dual licensed under the MIT and the University of Illinois Open |
| 7 | // Source Licenses. See LICENSE.TXT for details. |
| 8 | // |
| 9 | //===----------------------------------------------------------------------===// |
| 10 | |
| 11 | #ifndef _LIBCPP_EXPERIMENTAL_FUNCTIONAL |
| 12 | #define _LIBCPP_EXPERIMENTAL_FUNCTIONAL |
| 13 | |
| 14 | /* |
| 15 | experimental/functional synopsis |
| 16 | |
| 17 | #include <algorithm> |
| 18 | |
| 19 | namespace std { |
| 20 | namespace experimental { |
| 21 | inline namespace fundamentals_v1 { |
| 22 | |
| 23 | // See C++14 20.9.9, Function object binders |
| 24 | template <class T> constexpr bool is_bind_expression_v |
| 25 | = is_bind_expression<T>::value; |
| 26 | template <class T> constexpr int is_placeholder_v |
| 27 | = is_placeholder<T>::value; |
| 28 | |
| 29 | // 4.2, Class template function |
| 30 | template<class> class function; // undefined |
| 31 | template<class R, class... ArgTypes> class function<R(ArgTypes...)>; |
| 32 | |
| 33 | template<class R, class... ArgTypes> |
| 34 | void swap(function<R(ArgTypes...)>&, function<R(ArgTypes...)>&); |
| 35 | |
| 36 | template<class R, class... ArgTypes> |
| 37 | bool operator==(const function<R(ArgTypes...)>&, nullptr_t) noexcept; |
| 38 | template<class R, class... ArgTypes> |
| 39 | bool operator==(nullptr_t, const function<R(ArgTypes...)>&) noexcept; |
| 40 | template<class R, class... ArgTypes> |
| 41 | bool operator!=(const function<R(ArgTypes...)>&, nullptr_t) noexcept; |
| 42 | template<class R, class... ArgTypes> |
| 43 | bool operator!=(nullptr_t, const function<R(ArgTypes...)>&) noexcept; |
| 44 | |
| 45 | // 4.3, Searchers |
| 46 | template<class ForwardIterator, class BinaryPredicate = equal_to<>> |
| 47 | class default_searcher; |
| 48 | |
| 49 | template<class RandomAccessIterator, |
| 50 | class Hash = hash<typename iterator_traits<RandomAccessIterator>::value_type>, |
| 51 | class BinaryPredicate = equal_to<>> |
| 52 | class boyer_moore_searcher; |
| 53 | |
| 54 | template<class RandomAccessIterator, |
| 55 | class Hash = hash<typename iterator_traits<RandomAccessIterator>::value_type>, |
| 56 | class BinaryPredicate = equal_to<>> |
| 57 | class boyer_moore_horspool_searcher; |
| 58 | |
| 59 | template<class ForwardIterator, class BinaryPredicate = equal_to<>> |
| 60 | default_searcher<ForwardIterator, BinaryPredicate> |
| 61 | make_default_searcher(ForwardIterator pat_first, ForwardIterator pat_last, |
| 62 | BinaryPredicate pred = BinaryPredicate()); |
| 63 | |
| 64 | template<class RandomAccessIterator, |
| 65 | class Hash = hash<typename iterator_traits<RandomAccessIterator>::value_type>, |
| 66 | class BinaryPredicate = equal_to<>> |
| 67 | boyer_moore_searcher<RandomAccessIterator, Hash, BinaryPredicate> |
| 68 | make_boyer_moore_searcher( |
| 69 | RandomAccessIterator pat_first, RandomAccessIterator pat_last, |
| 70 | Hash hf = Hash(), BinaryPredicate pred = BinaryPredicate()); |
| 71 | |
| 72 | template<class RandomAccessIterator, |
| 73 | class Hash = hash<typename iterator_traits<RandomAccessIterator>::value_type>, |
| 74 | class BinaryPredicate = equal_to<>> |
| 75 | boyer_moore_horspool_searcher<RandomAccessIterator, Hash, BinaryPredicate> |
| 76 | make_boyer_moore_horspool_searcher( |
| 77 | RandomAccessIterator pat_first, RandomAccessIterator pat_last, |
| 78 | Hash hf = Hash(), BinaryPredicate pred = BinaryPredicate()); |
| 79 | |
| 80 | } // namespace fundamentals_v1 |
| 81 | } // namespace experimental |
| 82 | |
| 83 | template<class R, class... ArgTypes, class Alloc> |
| 84 | struct uses_allocator<experimental::function<R(ArgTypes...)>, Alloc>; |
| 85 | |
| 86 | } // namespace std |
| 87 | |
| 88 | */ |
| 89 | |
| 90 | #include <experimental/__config> |
| 91 | #include <functional> |
| 92 | |
| 93 | #include <algorithm> |
| 94 | #include <type_traits> |
| 95 | #include <vector> |
| 96 | #include <array> |
| 97 | #include <unordered_map> |
| 98 | |
| 99 | #include <__undef_min_max> |
| 100 | |
| 101 | #include <__debug> |
| 102 | |
| 103 | #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) |
| 104 | #pragma GCC system_header |
| 105 | #endif |
| 106 | |
| 107 | _LIBCPP_BEGIN_NAMESPACE_LFTS |
| 108 | |
| 109 | #if _LIBCPP_STD_VER > 11 |
| 110 | // default searcher |
| 111 | template<class _ForwardIterator, class _BinaryPredicate = equal_to<>> |
| 112 | _LIBCPP_TYPE_VIS |
| 113 | class default_searcher { |
| 114 | public: |
| 115 | _LIBCPP_INLINE_VISIBILITY |
| 116 | default_searcher(_ForwardIterator __f, _ForwardIterator __l, |
| 117 | _BinaryPredicate __p = _BinaryPredicate()) |
| 118 | : __first_(__f), __last_(__l), __pred_(__p) {} |
| 119 | |
| 120 | template <typename _ForwardIterator2> |
| 121 | _LIBCPP_INLINE_VISIBILITY |
| 122 | pair<_ForwardIterator2, _ForwardIterator2> |
| 123 | operator () (_ForwardIterator2 __f, _ForwardIterator2 __l) const |
| 124 | { |
| 125 | return _VSTD::__search(__f, __l, __first_, __last_, __pred_, |
| 126 | typename _VSTD::iterator_traits<_ForwardIterator>::iterator_category(), |
| 127 | typename _VSTD::iterator_traits<_ForwardIterator2>::iterator_category()); |
| 128 | } |
| 129 | |
| 130 | private: |
| 131 | _ForwardIterator __first_; |
| 132 | _ForwardIterator __last_; |
| 133 | _BinaryPredicate __pred_; |
| 134 | }; |
| 135 | |
| 136 | template<class _ForwardIterator, class _BinaryPredicate = equal_to<>> |
| 137 | _LIBCPP_INLINE_VISIBILITY |
| 138 | default_searcher<_ForwardIterator, _BinaryPredicate> |
| 139 | make_default_searcher( _ForwardIterator __f, _ForwardIterator __l, _BinaryPredicate __p = _BinaryPredicate ()) |
| 140 | { |
| 141 | return default_searcher<_ForwardIterator, _BinaryPredicate>(__f, __l, __p); |
| 142 | } |
| 143 | |
| 144 | template<class _Key, class _Value, class _Hash, class _BinaryPredicate, bool /*useArray*/> class _BMSkipTable; |
| 145 | |
| 146 | // General case for BM data searching; use a map |
| 147 | template<class _Key, typename _Value, class _Hash, class _BinaryPredicate> |
| 148 | class _BMSkipTable<_Key, _Value, _Hash, _BinaryPredicate, false> { |
| 149 | public: // TODO private: |
| 150 | typedef _Value value_type; |
| 151 | typedef _Key key_type; |
| 152 | |
| 153 | const _Value __default_value_; |
| 154 | std::unordered_map<_Key, _Value, _Hash, _BinaryPredicate> __table; |
| 155 | |
| 156 | public: |
| 157 | _LIBCPP_INLINE_VISIBILITY |
| 158 | _BMSkipTable(std::size_t __sz, _Value __default, _Hash __hf, _BinaryPredicate __pred) |
| 159 | : __default_value_(__default), __table(__sz, __hf, __pred) {} |
| 160 | |
| 161 | _LIBCPP_INLINE_VISIBILITY |
| 162 | void insert(const key_type &__key, value_type __val) |
| 163 | { |
| 164 | __table [__key] = __val; // Would skip_.insert (val) be better here? |
| 165 | } |
| 166 | |
| 167 | _LIBCPP_INLINE_VISIBILITY |
| 168 | value_type operator [](const key_type & __key) const |
| 169 | { |
| 170 | auto __it = __table.find (__key); |
| 171 | return __it == __table.end() ? __default_value_ : __it->second; |
| 172 | } |
| 173 | }; |
| 174 | |
| 175 | |
| 176 | // Special case small numeric values; use an array |
| 177 | template<class _Key, typename _Value, class _Hash, class _BinaryPredicate> |
| 178 | class _BMSkipTable<_Key, _Value, _Hash, _BinaryPredicate, true> { |
| 179 | private: |
| 180 | typedef _Value value_type; |
| 181 | typedef _Key key_type; |
| 182 | |
| 183 | typedef typename std::make_unsigned<key_type>::type unsigned_key_type; |
| 184 | typedef std::array<value_type, _VSTD::numeric_limits<unsigned_key_type>::max()> skip_map; |
| 185 | skip_map __table; |
| 186 | |
| 187 | public: |
| 188 | _LIBCPP_INLINE_VISIBILITY |
| 189 | _BMSkipTable(std::size_t /*__sz*/, _Value __default, _Hash /*__hf*/, _BinaryPredicate /*__pred*/) |
| 190 | { |
| 191 | std::fill_n(__table.begin(), __table.size(), __default); |
| 192 | } |
| 193 | |
| 194 | _LIBCPP_INLINE_VISIBILITY |
| 195 | void insert(key_type __key, value_type __val) |
| 196 | { |
| 197 | __table[static_cast<unsigned_key_type>(__key)] = __val; |
| 198 | } |
| 199 | |
| 200 | _LIBCPP_INLINE_VISIBILITY |
| 201 | value_type operator [](key_type __key) const |
| 202 | { |
| 203 | return __table[static_cast<unsigned_key_type>(__key)]; |
| 204 | } |
| 205 | }; |
| 206 | |
| 207 | |
| 208 | template <class _RandomAccessIterator1, |
| 209 | class _Hash = hash<typename iterator_traits<_RandomAccessIterator1>::value_type>, |
| 210 | class _BinaryPredicate = equal_to<>> |
| 211 | _LIBCPP_TYPE_VIS |
| 212 | class boyer_moore_searcher { |
| 213 | private: |
| 214 | typedef typename std::iterator_traits<_RandomAccessIterator1>::difference_type difference_type; |
| 215 | typedef typename std::iterator_traits<_RandomAccessIterator1>::value_type value_type; |
| 216 | typedef _BMSkipTable<value_type, difference_type, _Hash, _BinaryPredicate, |
| 217 | _VSTD::is_integral<value_type>::value && // what about enums? |
| 218 | sizeof(value_type) == 1 && |
| 219 | is_same<_Hash, hash<value_type>>::value && |
| 220 | is_same<_BinaryPredicate, equal_to<>>::value |
| 221 | > skip_table_type; |
| 222 | |
| 223 | public: |
| 224 | boyer_moore_searcher(_RandomAccessIterator1 __f, _RandomAccessIterator1 __l, |
| 225 | _Hash __hf = _Hash(), _BinaryPredicate __pred = _BinaryPredicate()) |
| 226 | : __first_(__f), __last_(__l), __pred_(__pred), |
| 227 | __pattern_length_(_VSTD::distance(__first_, __last_)), |
| 228 | __skip_{make_shared<skip_table_type>(__pattern_length_, -1, __hf, __pred_)}, |
| 229 | __suffix_{make_shared<vector<difference_type>>(__pattern_length_ + 1)} |
| 230 | { |
| 231 | // build the skip table |
| 232 | for ( difference_type __i = 0; __f != __l; ++__f, (void) ++__i ) |
| 233 | __skip_->insert(*__f, __i); |
| 234 | |
| 235 | this->__build_suffix_table ( __first_, __last_, __pred_ ); |
| 236 | } |
| 237 | |
| 238 | template <typename _RandomAccessIterator2> |
| 239 | pair<_RandomAccessIterator2, _RandomAccessIterator2> |
| 240 | operator ()(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const |
| 241 | { |
| 242 | static_assert ( std::is_same< |
| 243 | typename std::decay<typename std::iterator_traits<_RandomAccessIterator1>::value_type>::type, |
| 244 | typename std::decay<typename std::iterator_traits<_RandomAccessIterator2>::value_type>::type |
| 245 | >::value, |
| 246 | "Corpus and Pattern iterators must point to the same type" ); |
| 247 | |
| 248 | if (__f == __l ) return make_pair(__l, __l); // empty corpus |
| 249 | if (__first_ == __last_) return make_pair(__f, __f); // empty pattern |
| 250 | |
| 251 | // If the pattern is larger than the corpus, we can't find it! |
| 252 | if ( __pattern_length_ > _VSTD::distance (__f, __l)) |
| 253 | return make_pair(__l, __l); |
| 254 | |
| 255 | // Do the search |
| 256 | return this->__search(__f, __l); |
| 257 | } |
| 258 | |
| 259 | public: // TODO private: |
| 260 | _RandomAccessIterator1 __first_; |
| 261 | _RandomAccessIterator1 __last_; |
| 262 | _BinaryPredicate __pred_; |
| 263 | difference_type __pattern_length_; |
| 264 | shared_ptr<skip_table_type> __skip_; |
| 265 | shared_ptr<vector<difference_type>> __suffix_; |
| 266 | |
| 267 | template <typename _RandomAccessIterator2> |
| 268 | pair<_RandomAccessIterator2, _RandomAccessIterator2> |
| 269 | __search(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const |
| 270 | { |
| 271 | _RandomAccessIterator2 __cur = __f; |
| 272 | const _RandomAccessIterator2 __last = __l - __pattern_length_; |
| 273 | const skip_table_type & __skip = *__skip_.get(); |
| 274 | const vector<difference_type> & __suffix = *__suffix_.get(); |
| 275 | |
| 276 | while (__cur <= __last) |
| 277 | { |
| 278 | |
| 279 | // Do we match right where we are? |
| 280 | difference_type __j = __pattern_length_; |
| 281 | while (__pred_(__first_ [__j-1], __cur [__j-1])) { |
| 282 | __j--; |
| 283 | // We matched - we're done! |
| 284 | if ( __j == 0 ) |
| 285 | return make_pair(__cur, __cur + __pattern_length_); |
| 286 | } |
| 287 | |
| 288 | // Since we didn't match, figure out how far to skip forward |
| 289 | difference_type __k = __skip[__cur [ __j - 1 ]]; |
| 290 | difference_type __m = __j - __k - 1; |
| 291 | if (__k < __j && __m > __suffix[ __j ]) |
| 292 | __cur += __m; |
| 293 | else |
| 294 | __cur += __suffix[ __j ]; |
| 295 | } |
| 296 | |
| 297 | return make_pair(__l, __l); // We didn't find anything |
| 298 | } |
| 299 | |
| 300 | |
| 301 | template<typename _Iterator, typename _Container> |
| 302 | void __compute_bm_prefix ( _Iterator __f, _Iterator __l, _BinaryPredicate __pred, _Container &__prefix ) |
| 303 | { |
| 304 | const std::size_t __count = _VSTD::distance(__f, __l); |
| 305 | |
| 306 | __prefix[0] = 0; |
| 307 | std::size_t __k = 0; |
| 308 | for ( std::size_t __i = 1; __i < __count; ++__i ) |
| 309 | { |
| 310 | while ( __k > 0 && !__pred ( __f[__k], __f[__i] )) |
| 311 | __k = __prefix [ __k - 1 ]; |
| 312 | |
| 313 | if ( __pred ( __f[__k], __f[__i] )) |
| 314 | __k++; |
| 315 | __prefix [ __i ] = __k; |
| 316 | } |
| 317 | } |
| 318 | |
| 319 | void __build_suffix_table(_RandomAccessIterator1 __f, _RandomAccessIterator1 __l, |
| 320 | _BinaryPredicate __pred) |
| 321 | { |
| 322 | const std::size_t __count = _VSTD::distance(__f, __l); |
| 323 | vector<difference_type> & __suffix = *__suffix_.get(); |
| 324 | if (__count > 0) |
| 325 | { |
| 326 | _VSTD::vector<value_type> __scratch(__count); |
| 327 | |
| 328 | __compute_bm_prefix(__f, __l, __pred, __scratch); |
| 329 | for ( std::size_t __i = 0; __i <= __count; __i++ ) |
| 330 | __suffix[__i] = __count - __scratch[__count-1]; |
| 331 | |
| 332 | typedef _VSTD::reverse_iterator<_RandomAccessIterator1> _RevIter; |
| 333 | __compute_bm_prefix(_RevIter(__l), _RevIter(__f), __pred, __scratch); |
| 334 | |
| 335 | for ( std::size_t __i = 0; __i < __count; __i++ ) |
| 336 | { |
| 337 | const std::size_t __j = __count - __scratch[__i]; |
| 338 | const difference_type __k = __i - __scratch[__i] + 1; |
| 339 | |
| 340 | if (__suffix[__j] > __k) |
| 341 | __suffix[__j] = __k; |
| 342 | } |
| 343 | } |
| 344 | } |
| 345 | |
| 346 | }; |
| 347 | |
| 348 | template<class _RandomAccessIterator, |
| 349 | class _Hash = hash<typename iterator_traits<_RandomAccessIterator>::value_type>, |
| 350 | class _BinaryPredicate = equal_to<>> |
| 351 | _LIBCPP_INLINE_VISIBILITY |
| 352 | boyer_moore_searcher<_RandomAccessIterator, _Hash, _BinaryPredicate> |
| 353 | make_boyer_moore_searcher( _RandomAccessIterator __f, _RandomAccessIterator __l, |
| 354 | _Hash __hf = _Hash(), _BinaryPredicate __p = _BinaryPredicate ()) |
| 355 | { |
| 356 | return boyer_moore_searcher<_RandomAccessIterator, _Hash, _BinaryPredicate>(__f, __l, __hf, __p); |
| 357 | } |
| 358 | |
| 359 | // boyer-moore-horspool |
| 360 | template <class _RandomAccessIterator1, |
| 361 | class _Hash = hash<typename iterator_traits<_RandomAccessIterator1>::value_type>, |
| 362 | class _BinaryPredicate = equal_to<>> |
| 363 | _LIBCPP_TYPE_VIS |
| 364 | class boyer_moore_horspool_searcher { |
| 365 | private: |
| 366 | typedef typename std::iterator_traits<_RandomAccessIterator1>::difference_type difference_type; |
| 367 | typedef typename std::iterator_traits<_RandomAccessIterator1>::value_type value_type; |
| 368 | typedef _BMSkipTable<value_type, difference_type, _Hash, _BinaryPredicate, |
| 369 | _VSTD::is_integral<value_type>::value && // what about enums? |
| 370 | sizeof(value_type) == 1 && |
| 371 | is_same<_Hash, hash<value_type>>::value && |
| 372 | is_same<_BinaryPredicate, equal_to<>>::value |
| 373 | > skip_table_type; |
| 374 | |
| 375 | public: |
| 376 | boyer_moore_horspool_searcher(_RandomAccessIterator1 __f, _RandomAccessIterator1 __l, |
| 377 | _Hash __hf = _Hash(), _BinaryPredicate __pred = _BinaryPredicate()) |
| 378 | : __first_(__f), __last_(__l), __pred_(__pred), |
| 379 | __pattern_length_(_VSTD::distance(__first_, __last_)), |
| 380 | __skip_{_VSTD::make_shared<skip_table_type>(__pattern_length_, __pattern_length_, __hf, __pred_)} |
| 381 | { |
| 382 | // build the skip table |
| 383 | if ( __f != __l ) |
| 384 | { |
| 385 | __l = __l - 1; |
| 386 | for ( difference_type __i = 0; __f != __l; ++__f, (void) ++__i ) |
| 387 | __skip_->insert(*__f, __pattern_length_ - 1 - __i); |
| 388 | } |
| 389 | } |
| 390 | |
| 391 | template <typename _RandomAccessIterator2> |
| 392 | pair<_RandomAccessIterator2, _RandomAccessIterator2> |
| 393 | operator ()(_RandomAccessIterator2 __f, _RandomAccessIterator2 __l) const |
| 394 | { |
| 395 | static_assert ( std::is_same< |
| 396 | typename std::decay<typename std::iterator_traits<_RandomAccessIterator1>::value_type>::type, |
| 397 | typename std::decay<typename std::iterator_traits<_RandomAccessIterator2>::value_type>::type |
| 398 | >::value, |
| 399 | "Corpus and Pattern iterators must point to the same type" ); |
| 400 | |
| 401 | if (__f == __l ) return make_pair(__l, __l); // empty corpus |
| 402 | if (__first_ == __last_) return make_pair(__f, __f); // empty pattern |
| 403 | |
| 404 | // If the pattern is larger than the corpus, we can't find it! |
| 405 | if ( __pattern_length_ > _VSTD::distance (__f, __l)) |
| 406 | return make_pair(__l, __l); |
| 407 | |
| 408 | // Do the search |
| 409 | return this->__search(__f, __l); |
| 410 | } |
| 411 | |
| 412 | private: |
| 413 | _RandomAccessIterator1 __first_; |
| 414 | _RandomAccessIterator1 __last_; |
| 415 | _BinaryPredicate __pred_; |
| 416 | difference_type __pattern_length_; |
| 417 | shared_ptr<skip_table_type> __skip_; |
| 418 | |
| 419 | template <typename _RandomAccessIterator2> |
| 420 | pair<_RandomAccessIterator2, _RandomAccessIterator2> |
| 421 | __search ( _RandomAccessIterator2 __f, _RandomAccessIterator2 __l ) const { |
| 422 | _RandomAccessIterator2 __cur = __f; |
| 423 | const _RandomAccessIterator2 __last = __l - __pattern_length_; |
| 424 | const skip_table_type & __skip = *__skip_.get(); |
| 425 | |
| 426 | while (__cur <= __last) |
| 427 | { |
| 428 | // Do we match right where we are? |
| 429 | difference_type __j = __pattern_length_; |
| 430 | while (__pred_(__first_[__j-1], __cur[__j-1])) |
| 431 | { |
| 432 | __j--; |
| 433 | // We matched - we're done! |
| 434 | if ( __j == 0 ) |
| 435 | return make_pair(__cur, __cur + __pattern_length_); |
| 436 | } |
| 437 | __cur += __skip[__cur[__pattern_length_-1]]; |
| 438 | } |
| 439 | |
| 440 | return make_pair(__l, __l); |
| 441 | } |
| 442 | }; |
| 443 | |
| 444 | template<class _RandomAccessIterator, |
| 445 | class _Hash = hash<typename iterator_traits<_RandomAccessIterator>::value_type>, |
| 446 | class _BinaryPredicate = equal_to<>> |
| 447 | _LIBCPP_INLINE_VISIBILITY |
| 448 | boyer_moore_horspool_searcher<_RandomAccessIterator, _Hash, _BinaryPredicate> |
| 449 | make_boyer_moore_horspool_searcher( _RandomAccessIterator __f, _RandomAccessIterator __l, |
| 450 | _Hash __hf = _Hash(), _BinaryPredicate __p = _BinaryPredicate ()) |
| 451 | { |
| 452 | return boyer_moore_horspool_searcher<_RandomAccessIterator, _Hash, _BinaryPredicate>(__f, __l, __hf, __p); |
| 453 | } |
| 454 | |
| 455 | #endif // _LIBCPP_STD_VER > 11 |
| 456 | |
| 457 | _LIBCPP_END_NAMESPACE_LFTS |
| 458 | |
| 459 | #endif /* _LIBCPP_EXPERIMENTAL_FUNCTIONAL */ |