Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1 | // Copyright 2012 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef V8_REGEXP_JSREGEXP_H_ |
| 6 | #define V8_REGEXP_JSREGEXP_H_ |
| 7 | |
| 8 | #include "src/allocation.h" |
| 9 | #include "src/assembler.h" |
| 10 | #include "src/regexp/regexp-ast.h" |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 11 | #include "src/regexp/regexp-macro-assembler.h" |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 12 | |
| 13 | namespace v8 { |
| 14 | namespace internal { |
| 15 | |
| 16 | class NodeVisitor; |
| 17 | class RegExpCompiler; |
| 18 | class RegExpMacroAssembler; |
| 19 | class RegExpNode; |
| 20 | class RegExpTree; |
| 21 | class BoyerMooreLookahead; |
| 22 | |
| 23 | class RegExpImpl { |
| 24 | public: |
| 25 | // Whether V8 is compiled with native regexp support or not. |
| 26 | static bool UsesNativeRegExp() { |
| 27 | #ifdef V8_INTERPRETED_REGEXP |
| 28 | return false; |
| 29 | #else |
| 30 | return true; |
| 31 | #endif |
| 32 | } |
| 33 | |
| 34 | // Returns a string representation of a regular expression. |
| 35 | // Implements RegExp.prototype.toString, see ECMA-262 section 15.10.6.4. |
| 36 | // This function calls the garbage collector if necessary. |
| 37 | static Handle<String> ToString(Handle<Object> value); |
| 38 | |
| 39 | // Parses the RegExp pattern and prepares the JSRegExp object with |
| 40 | // generic data and choice of implementation - as well as what |
| 41 | // the implementation wants to store in the data field. |
| 42 | // Returns false if compilation fails. |
| 43 | MUST_USE_RESULT static MaybeHandle<Object> Compile(Handle<JSRegExp> re, |
| 44 | Handle<String> pattern, |
| 45 | JSRegExp::Flags flags); |
| 46 | |
| 47 | // See ECMA-262 section 15.10.6.2. |
| 48 | // This function calls the garbage collector if necessary. |
| 49 | MUST_USE_RESULT static MaybeHandle<Object> Exec( |
| 50 | Handle<JSRegExp> regexp, |
| 51 | Handle<String> subject, |
| 52 | int index, |
| 53 | Handle<JSArray> lastMatchInfo); |
| 54 | |
| 55 | // Prepares a JSRegExp object with Irregexp-specific data. |
| 56 | static void IrregexpInitialize(Handle<JSRegExp> re, |
| 57 | Handle<String> pattern, |
| 58 | JSRegExp::Flags flags, |
| 59 | int capture_register_count); |
| 60 | |
| 61 | |
| 62 | static void AtomCompile(Handle<JSRegExp> re, |
| 63 | Handle<String> pattern, |
| 64 | JSRegExp::Flags flags, |
| 65 | Handle<String> match_pattern); |
| 66 | |
| 67 | |
| 68 | static int AtomExecRaw(Handle<JSRegExp> regexp, |
| 69 | Handle<String> subject, |
| 70 | int index, |
| 71 | int32_t* output, |
| 72 | int output_size); |
| 73 | |
| 74 | |
| 75 | static Handle<Object> AtomExec(Handle<JSRegExp> regexp, |
| 76 | Handle<String> subject, |
| 77 | int index, |
| 78 | Handle<JSArray> lastMatchInfo); |
| 79 | |
| 80 | enum IrregexpResult { RE_FAILURE = 0, RE_SUCCESS = 1, RE_EXCEPTION = -1 }; |
| 81 | |
| 82 | // Prepare a RegExp for being executed one or more times (using |
| 83 | // IrregexpExecOnce) on the subject. |
| 84 | // This ensures that the regexp is compiled for the subject, and that |
| 85 | // the subject is flat. |
| 86 | // Returns the number of integer spaces required by IrregexpExecOnce |
| 87 | // as its "registers" argument. If the regexp cannot be compiled, |
| 88 | // an exception is set as pending, and this function returns negative. |
| 89 | static int IrregexpPrepare(Handle<JSRegExp> regexp, |
| 90 | Handle<String> subject); |
| 91 | |
| 92 | // Execute a regular expression on the subject, starting from index. |
| 93 | // If matching succeeds, return the number of matches. This can be larger |
| 94 | // than one in the case of global regular expressions. |
| 95 | // The captures and subcaptures are stored into the registers vector. |
| 96 | // If matching fails, returns RE_FAILURE. |
| 97 | // If execution fails, sets a pending exception and returns RE_EXCEPTION. |
| 98 | static int IrregexpExecRaw(Handle<JSRegExp> regexp, |
| 99 | Handle<String> subject, |
| 100 | int index, |
| 101 | int32_t* output, |
| 102 | int output_size); |
| 103 | |
| 104 | // Execute an Irregexp bytecode pattern. |
| 105 | // On a successful match, the result is a JSArray containing |
| 106 | // captured positions. On a failure, the result is the null value. |
| 107 | // Returns an empty handle in case of an exception. |
| 108 | MUST_USE_RESULT static MaybeHandle<Object> IrregexpExec( |
| 109 | Handle<JSRegExp> regexp, |
| 110 | Handle<String> subject, |
| 111 | int index, |
| 112 | Handle<JSArray> lastMatchInfo); |
| 113 | |
| 114 | // Set last match info. If match is NULL, then setting captures is omitted. |
| 115 | static Handle<JSArray> SetLastMatchInfo(Handle<JSArray> last_match_info, |
| 116 | Handle<String> subject, |
| 117 | int capture_count, |
| 118 | int32_t* match); |
| 119 | |
| 120 | |
| 121 | class GlobalCache { |
| 122 | public: |
| 123 | GlobalCache(Handle<JSRegExp> regexp, |
| 124 | Handle<String> subject, |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 125 | Isolate* isolate); |
| 126 | |
| 127 | INLINE(~GlobalCache()); |
| 128 | |
| 129 | // Fetch the next entry in the cache for global regexp match results. |
| 130 | // This does not set the last match info. Upon failure, NULL is returned. |
| 131 | // The cause can be checked with Result(). The previous |
| 132 | // result is still in available in memory when a failure happens. |
| 133 | INLINE(int32_t* FetchNext()); |
| 134 | |
| 135 | INLINE(int32_t* LastSuccessfulMatch()); |
| 136 | |
| 137 | INLINE(bool HasException()) { return num_matches_ < 0; } |
| 138 | |
| 139 | private: |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 140 | int AdvanceZeroLength(int last_index); |
| 141 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 142 | int num_matches_; |
| 143 | int max_matches_; |
| 144 | int current_match_index_; |
| 145 | int registers_per_match_; |
| 146 | // Pointer to the last set of captures. |
| 147 | int32_t* register_array_; |
| 148 | int register_array_size_; |
| 149 | Handle<JSRegExp> regexp_; |
| 150 | Handle<String> subject_; |
| 151 | }; |
| 152 | |
| 153 | |
| 154 | // Array index in the lastMatchInfo array. |
| 155 | static const int kLastCaptureCount = 0; |
| 156 | static const int kLastSubject = 1; |
| 157 | static const int kLastInput = 2; |
| 158 | static const int kFirstCapture = 3; |
| 159 | static const int kLastMatchOverhead = 3; |
| 160 | |
| 161 | // Direct offset into the lastMatchInfo array. |
| 162 | static const int kLastCaptureCountOffset = |
| 163 | FixedArray::kHeaderSize + kLastCaptureCount * kPointerSize; |
| 164 | static const int kLastSubjectOffset = |
| 165 | FixedArray::kHeaderSize + kLastSubject * kPointerSize; |
| 166 | static const int kLastInputOffset = |
| 167 | FixedArray::kHeaderSize + kLastInput * kPointerSize; |
| 168 | static const int kFirstCaptureOffset = |
| 169 | FixedArray::kHeaderSize + kFirstCapture * kPointerSize; |
| 170 | |
| 171 | // Used to access the lastMatchInfo array. |
| 172 | static int GetCapture(FixedArray* array, int index) { |
| 173 | return Smi::cast(array->get(index + kFirstCapture))->value(); |
| 174 | } |
| 175 | |
| 176 | static void SetLastCaptureCount(FixedArray* array, int to) { |
| 177 | array->set(kLastCaptureCount, Smi::FromInt(to)); |
| 178 | } |
| 179 | |
| 180 | static void SetLastSubject(FixedArray* array, String* to) { |
| 181 | array->set(kLastSubject, to); |
| 182 | } |
| 183 | |
| 184 | static void SetLastInput(FixedArray* array, String* to) { |
| 185 | array->set(kLastInput, to); |
| 186 | } |
| 187 | |
| 188 | static void SetCapture(FixedArray* array, int index, int to) { |
| 189 | array->set(index + kFirstCapture, Smi::FromInt(to)); |
| 190 | } |
| 191 | |
| 192 | static int GetLastCaptureCount(FixedArray* array) { |
| 193 | return Smi::cast(array->get(kLastCaptureCount))->value(); |
| 194 | } |
| 195 | |
| 196 | // For acting on the JSRegExp data FixedArray. |
| 197 | static int IrregexpMaxRegisterCount(FixedArray* re); |
| 198 | static void SetIrregexpMaxRegisterCount(FixedArray* re, int value); |
| 199 | static int IrregexpNumberOfCaptures(FixedArray* re); |
| 200 | static int IrregexpNumberOfRegisters(FixedArray* re); |
| 201 | static ByteArray* IrregexpByteCode(FixedArray* re, bool is_one_byte); |
| 202 | static Code* IrregexpNativeCode(FixedArray* re, bool is_one_byte); |
| 203 | |
| 204 | // Limit the space regexps take up on the heap. In order to limit this we |
| 205 | // would like to keep track of the amount of regexp code on the heap. This |
| 206 | // is not tracked, however. As a conservative approximation we track the |
| 207 | // total regexp code compiled including code that has subsequently been freed |
| 208 | // and the total executable memory at any point. |
| 209 | static const int kRegExpExecutableMemoryLimit = 16 * MB; |
| 210 | static const int kRegExpCompiledLimit = 1 * MB; |
| 211 | static const int kRegExpTooLargeToOptimize = 20 * KB; |
| 212 | |
| 213 | private: |
| 214 | static bool CompileIrregexp(Handle<JSRegExp> re, |
| 215 | Handle<String> sample_subject, bool is_one_byte); |
| 216 | static inline bool EnsureCompiledIrregexp(Handle<JSRegExp> re, |
| 217 | Handle<String> sample_subject, |
| 218 | bool is_one_byte); |
| 219 | }; |
| 220 | |
| 221 | |
| 222 | // Represents the location of one element relative to the intersection of |
| 223 | // two sets. Corresponds to the four areas of a Venn diagram. |
| 224 | enum ElementInSetsRelation { |
| 225 | kInsideNone = 0, |
| 226 | kInsideFirst = 1, |
| 227 | kInsideSecond = 2, |
| 228 | kInsideBoth = 3 |
| 229 | }; |
| 230 | |
| 231 | |
| 232 | // A set of unsigned integers that behaves especially well on small |
| 233 | // integers (< 32). May do zone-allocation. |
| 234 | class OutSet: public ZoneObject { |
| 235 | public: |
| 236 | OutSet() : first_(0), remaining_(NULL), successors_(NULL) { } |
| 237 | OutSet* Extend(unsigned value, Zone* zone); |
| 238 | bool Get(unsigned value) const; |
| 239 | static const unsigned kFirstLimit = 32; |
| 240 | |
| 241 | private: |
| 242 | // Destructively set a value in this set. In most cases you want |
| 243 | // to use Extend instead to ensure that only one instance exists |
| 244 | // that contains the same values. |
| 245 | void Set(unsigned value, Zone* zone); |
| 246 | |
| 247 | // The successors are a list of sets that contain the same values |
| 248 | // as this set and the one more value that is not present in this |
| 249 | // set. |
| 250 | ZoneList<OutSet*>* successors(Zone* zone) { return successors_; } |
| 251 | |
| 252 | OutSet(uint32_t first, ZoneList<unsigned>* remaining) |
| 253 | : first_(first), remaining_(remaining), successors_(NULL) { } |
| 254 | uint32_t first_; |
| 255 | ZoneList<unsigned>* remaining_; |
| 256 | ZoneList<OutSet*>* successors_; |
| 257 | friend class Trace; |
| 258 | }; |
| 259 | |
| 260 | |
| 261 | // A mapping from integers, specified as ranges, to a set of integers. |
| 262 | // Used for mapping character ranges to choices. |
| 263 | class DispatchTable : public ZoneObject { |
| 264 | public: |
| 265 | explicit DispatchTable(Zone* zone) : tree_(zone) { } |
| 266 | |
| 267 | class Entry { |
| 268 | public: |
| 269 | Entry() : from_(0), to_(0), out_set_(NULL) { } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 270 | Entry(uc32 from, uc32 to, OutSet* out_set) |
| 271 | : from_(from), to_(to), out_set_(out_set) { |
| 272 | DCHECK(from <= to); |
| 273 | } |
| 274 | uc32 from() { return from_; } |
| 275 | uc32 to() { return to_; } |
| 276 | void set_to(uc32 value) { to_ = value; } |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 277 | void AddValue(int value, Zone* zone) { |
| 278 | out_set_ = out_set_->Extend(value, zone); |
| 279 | } |
| 280 | OutSet* out_set() { return out_set_; } |
| 281 | private: |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 282 | uc32 from_; |
| 283 | uc32 to_; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 284 | OutSet* out_set_; |
| 285 | }; |
| 286 | |
| 287 | class Config { |
| 288 | public: |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 289 | typedef uc32 Key; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 290 | typedef Entry Value; |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 291 | static const uc32 kNoKey; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 292 | static const Entry NoValue() { return Value(); } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 293 | static inline int Compare(uc32 a, uc32 b) { |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 294 | if (a == b) |
| 295 | return 0; |
| 296 | else if (a < b) |
| 297 | return -1; |
| 298 | else |
| 299 | return 1; |
| 300 | } |
| 301 | }; |
| 302 | |
| 303 | void AddRange(CharacterRange range, int value, Zone* zone); |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 304 | OutSet* Get(uc32 value); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 305 | void Dump(); |
| 306 | |
| 307 | template <typename Callback> |
| 308 | void ForEach(Callback* callback) { |
| 309 | return tree()->ForEach(callback); |
| 310 | } |
| 311 | |
| 312 | private: |
| 313 | // There can't be a static empty set since it allocates its |
| 314 | // successors in a zone and caches them. |
| 315 | OutSet* empty() { return &empty_; } |
| 316 | OutSet empty_; |
| 317 | ZoneSplayTree<Config>* tree() { return &tree_; } |
| 318 | ZoneSplayTree<Config> tree_; |
| 319 | }; |
| 320 | |
| 321 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 322 | // Categorizes character ranges into BMP, non-BMP, lead, and trail surrogates. |
| 323 | class UnicodeRangeSplitter { |
| 324 | public: |
| 325 | UnicodeRangeSplitter(Zone* zone, ZoneList<CharacterRange>* base); |
| 326 | void Call(uc32 from, DispatchTable::Entry entry); |
| 327 | |
| 328 | ZoneList<CharacterRange>* bmp() { return bmp_; } |
| 329 | ZoneList<CharacterRange>* lead_surrogates() { return lead_surrogates_; } |
| 330 | ZoneList<CharacterRange>* trail_surrogates() { return trail_surrogates_; } |
| 331 | ZoneList<CharacterRange>* non_bmp() const { return non_bmp_; } |
| 332 | |
| 333 | private: |
| 334 | static const int kBase = 0; |
| 335 | // Separate ranges into |
| 336 | static const int kBmpCodePoints = 1; |
| 337 | static const int kLeadSurrogates = 2; |
| 338 | static const int kTrailSurrogates = 3; |
| 339 | static const int kNonBmpCodePoints = 4; |
| 340 | |
| 341 | Zone* zone_; |
| 342 | DispatchTable table_; |
| 343 | ZoneList<CharacterRange>* bmp_; |
| 344 | ZoneList<CharacterRange>* lead_surrogates_; |
| 345 | ZoneList<CharacterRange>* trail_surrogates_; |
| 346 | ZoneList<CharacterRange>* non_bmp_; |
| 347 | }; |
| 348 | |
| 349 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 350 | #define FOR_EACH_NODE_TYPE(VISIT) \ |
| 351 | VISIT(End) \ |
| 352 | VISIT(Action) \ |
| 353 | VISIT(Choice) \ |
| 354 | VISIT(BackReference) \ |
| 355 | VISIT(Assertion) \ |
| 356 | VISIT(Text) |
| 357 | |
| 358 | |
| 359 | class Trace; |
| 360 | struct PreloadState; |
| 361 | class GreedyLoopState; |
| 362 | class AlternativeGenerationList; |
| 363 | |
| 364 | struct NodeInfo { |
| 365 | NodeInfo() |
| 366 | : being_analyzed(false), |
| 367 | been_analyzed(false), |
| 368 | follows_word_interest(false), |
| 369 | follows_newline_interest(false), |
| 370 | follows_start_interest(false), |
| 371 | at_end(false), |
| 372 | visited(false), |
| 373 | replacement_calculated(false) { } |
| 374 | |
| 375 | // Returns true if the interests and assumptions of this node |
| 376 | // matches the given one. |
| 377 | bool Matches(NodeInfo* that) { |
| 378 | return (at_end == that->at_end) && |
| 379 | (follows_word_interest == that->follows_word_interest) && |
| 380 | (follows_newline_interest == that->follows_newline_interest) && |
| 381 | (follows_start_interest == that->follows_start_interest); |
| 382 | } |
| 383 | |
| 384 | // Updates the interests of this node given the interests of the |
| 385 | // node preceding it. |
| 386 | void AddFromPreceding(NodeInfo* that) { |
| 387 | at_end |= that->at_end; |
| 388 | follows_word_interest |= that->follows_word_interest; |
| 389 | follows_newline_interest |= that->follows_newline_interest; |
| 390 | follows_start_interest |= that->follows_start_interest; |
| 391 | } |
| 392 | |
| 393 | bool HasLookbehind() { |
| 394 | return follows_word_interest || |
| 395 | follows_newline_interest || |
| 396 | follows_start_interest; |
| 397 | } |
| 398 | |
| 399 | // Sets the interests of this node to include the interests of the |
| 400 | // following node. |
| 401 | void AddFromFollowing(NodeInfo* that) { |
| 402 | follows_word_interest |= that->follows_word_interest; |
| 403 | follows_newline_interest |= that->follows_newline_interest; |
| 404 | follows_start_interest |= that->follows_start_interest; |
| 405 | } |
| 406 | |
| 407 | void ResetCompilationState() { |
| 408 | being_analyzed = false; |
| 409 | been_analyzed = false; |
| 410 | } |
| 411 | |
| 412 | bool being_analyzed: 1; |
| 413 | bool been_analyzed: 1; |
| 414 | |
| 415 | // These bits are set of this node has to know what the preceding |
| 416 | // character was. |
| 417 | bool follows_word_interest: 1; |
| 418 | bool follows_newline_interest: 1; |
| 419 | bool follows_start_interest: 1; |
| 420 | |
| 421 | bool at_end: 1; |
| 422 | bool visited: 1; |
| 423 | bool replacement_calculated: 1; |
| 424 | }; |
| 425 | |
| 426 | |
| 427 | // Details of a quick mask-compare check that can look ahead in the |
| 428 | // input stream. |
| 429 | class QuickCheckDetails { |
| 430 | public: |
| 431 | QuickCheckDetails() |
| 432 | : characters_(0), |
| 433 | mask_(0), |
| 434 | value_(0), |
| 435 | cannot_match_(false) { } |
| 436 | explicit QuickCheckDetails(int characters) |
| 437 | : characters_(characters), |
| 438 | mask_(0), |
| 439 | value_(0), |
| 440 | cannot_match_(false) { } |
| 441 | bool Rationalize(bool one_byte); |
| 442 | // Merge in the information from another branch of an alternation. |
| 443 | void Merge(QuickCheckDetails* other, int from_index); |
| 444 | // Advance the current position by some amount. |
| 445 | void Advance(int by, bool one_byte); |
| 446 | void Clear(); |
| 447 | bool cannot_match() { return cannot_match_; } |
| 448 | void set_cannot_match() { cannot_match_ = true; } |
| 449 | struct Position { |
| 450 | Position() : mask(0), value(0), determines_perfectly(false) { } |
| 451 | uc16 mask; |
| 452 | uc16 value; |
| 453 | bool determines_perfectly; |
| 454 | }; |
| 455 | int characters() { return characters_; } |
| 456 | void set_characters(int characters) { characters_ = characters; } |
| 457 | Position* positions(int index) { |
| 458 | DCHECK(index >= 0); |
| 459 | DCHECK(index < characters_); |
| 460 | return positions_ + index; |
| 461 | } |
| 462 | uint32_t mask() { return mask_; } |
| 463 | uint32_t value() { return value_; } |
| 464 | |
| 465 | private: |
| 466 | // How many characters do we have quick check information from. This is |
| 467 | // the same for all branches of a choice node. |
| 468 | int characters_; |
| 469 | Position positions_[4]; |
| 470 | // These values are the condensate of the above array after Rationalize(). |
| 471 | uint32_t mask_; |
| 472 | uint32_t value_; |
| 473 | // If set to true, there is no way this quick check can match at all. |
| 474 | // E.g., if it requires to be at the start of the input, and isn't. |
| 475 | bool cannot_match_; |
| 476 | }; |
| 477 | |
| 478 | |
| 479 | extern int kUninitializedRegExpNodePlaceHolder; |
| 480 | |
| 481 | |
| 482 | class RegExpNode: public ZoneObject { |
| 483 | public: |
| 484 | explicit RegExpNode(Zone* zone) |
| 485 | : replacement_(NULL), on_work_list_(false), trace_count_(0), zone_(zone) { |
| 486 | bm_info_[0] = bm_info_[1] = NULL; |
| 487 | } |
| 488 | virtual ~RegExpNode(); |
| 489 | virtual void Accept(NodeVisitor* visitor) = 0; |
| 490 | // Generates a goto to this node or actually generates the code at this point. |
| 491 | virtual void Emit(RegExpCompiler* compiler, Trace* trace) = 0; |
| 492 | // How many characters must this node consume at a minimum in order to |
| 493 | // succeed. If we have found at least 'still_to_find' characters that |
| 494 | // must be consumed there is no need to ask any following nodes whether |
| 495 | // they are sure to eat any more characters. The not_at_start argument is |
| 496 | // used to indicate that we know we are not at the start of the input. In |
| 497 | // this case anchored branches will always fail and can be ignored when |
| 498 | // determining how many characters are consumed on success. |
| 499 | virtual int EatsAtLeast(int still_to_find, int budget, bool not_at_start) = 0; |
| 500 | // Emits some quick code that checks whether the preloaded characters match. |
| 501 | // Falls through on certain failure, jumps to the label on possible success. |
| 502 | // If the node cannot make a quick check it does nothing and returns false. |
| 503 | bool EmitQuickCheck(RegExpCompiler* compiler, |
| 504 | Trace* bounds_check_trace, |
| 505 | Trace* trace, |
| 506 | bool preload_has_checked_bounds, |
| 507 | Label* on_possible_success, |
| 508 | QuickCheckDetails* details_return, |
| 509 | bool fall_through_on_failure); |
| 510 | // For a given number of characters this returns a mask and a value. The |
| 511 | // next n characters are anded with the mask and compared with the value. |
| 512 | // A comparison failure indicates the node cannot match the next n characters. |
| 513 | // A comparison success indicates the node may match. |
| 514 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 515 | RegExpCompiler* compiler, |
| 516 | int characters_filled_in, |
| 517 | bool not_at_start) = 0; |
| 518 | static const int kNodeIsTooComplexForGreedyLoops = kMinInt; |
| 519 | virtual int GreedyLoopTextLength() { return kNodeIsTooComplexForGreedyLoops; } |
| 520 | // Only returns the successor for a text node of length 1 that matches any |
| 521 | // character and that has no guards on it. |
| 522 | virtual RegExpNode* GetSuccessorOfOmnivorousTextNode( |
| 523 | RegExpCompiler* compiler) { |
| 524 | return NULL; |
| 525 | } |
| 526 | |
| 527 | // Collects information on the possible code units (mod 128) that can match if |
| 528 | // we look forward. This is used for a Boyer-Moore-like string searching |
| 529 | // implementation. TODO(erikcorry): This should share more code with |
| 530 | // EatsAtLeast, GetQuickCheckDetails. The budget argument is used to limit |
| 531 | // the number of nodes we are willing to look at in order to create this data. |
| 532 | static const int kRecursionBudget = 200; |
| 533 | bool KeepRecursing(RegExpCompiler* compiler); |
| 534 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 535 | BoyerMooreLookahead* bm, bool not_at_start) { |
| 536 | UNREACHABLE(); |
| 537 | } |
| 538 | |
| 539 | // If we know that the input is one-byte then there are some nodes that can |
| 540 | // never match. This method returns a node that can be substituted for |
| 541 | // itself, or NULL if the node can never match. |
| 542 | virtual RegExpNode* FilterOneByte(int depth, bool ignore_case) { |
| 543 | return this; |
| 544 | } |
| 545 | // Helper for FilterOneByte. |
| 546 | RegExpNode* replacement() { |
| 547 | DCHECK(info()->replacement_calculated); |
| 548 | return replacement_; |
| 549 | } |
| 550 | RegExpNode* set_replacement(RegExpNode* replacement) { |
| 551 | info()->replacement_calculated = true; |
| 552 | replacement_ = replacement; |
| 553 | return replacement; // For convenience. |
| 554 | } |
| 555 | |
| 556 | // We want to avoid recalculating the lookahead info, so we store it on the |
| 557 | // node. Only info that is for this node is stored. We can tell that the |
| 558 | // info is for this node when offset == 0, so the information is calculated |
| 559 | // relative to this node. |
| 560 | void SaveBMInfo(BoyerMooreLookahead* bm, bool not_at_start, int offset) { |
| 561 | if (offset == 0) set_bm_info(not_at_start, bm); |
| 562 | } |
| 563 | |
| 564 | Label* label() { return &label_; } |
| 565 | // If non-generic code is generated for a node (i.e. the node is not at the |
| 566 | // start of the trace) then it cannot be reused. This variable sets a limit |
| 567 | // on how often we allow that to happen before we insist on starting a new |
| 568 | // trace and generating generic code for a node that can be reused by flushing |
| 569 | // the deferred actions in the current trace and generating a goto. |
| 570 | static const int kMaxCopiesCodeGenerated = 10; |
| 571 | |
| 572 | bool on_work_list() { return on_work_list_; } |
| 573 | void set_on_work_list(bool value) { on_work_list_ = value; } |
| 574 | |
| 575 | NodeInfo* info() { return &info_; } |
| 576 | |
| 577 | BoyerMooreLookahead* bm_info(bool not_at_start) { |
| 578 | return bm_info_[not_at_start ? 1 : 0]; |
| 579 | } |
| 580 | |
| 581 | Zone* zone() const { return zone_; } |
| 582 | |
| 583 | protected: |
| 584 | enum LimitResult { DONE, CONTINUE }; |
| 585 | RegExpNode* replacement_; |
| 586 | |
| 587 | LimitResult LimitVersions(RegExpCompiler* compiler, Trace* trace); |
| 588 | |
| 589 | void set_bm_info(bool not_at_start, BoyerMooreLookahead* bm) { |
| 590 | bm_info_[not_at_start ? 1 : 0] = bm; |
| 591 | } |
| 592 | |
| 593 | private: |
| 594 | static const int kFirstCharBudget = 10; |
| 595 | Label label_; |
| 596 | bool on_work_list_; |
| 597 | NodeInfo info_; |
| 598 | // This variable keeps track of how many times code has been generated for |
| 599 | // this node (in different traces). We don't keep track of where the |
| 600 | // generated code is located unless the code is generated at the start of |
| 601 | // a trace, in which case it is generic and can be reused by flushing the |
| 602 | // deferred operations in the current trace and generating a goto. |
| 603 | int trace_count_; |
| 604 | BoyerMooreLookahead* bm_info_[2]; |
| 605 | |
| 606 | Zone* zone_; |
| 607 | }; |
| 608 | |
| 609 | |
| 610 | class SeqRegExpNode: public RegExpNode { |
| 611 | public: |
| 612 | explicit SeqRegExpNode(RegExpNode* on_success) |
| 613 | : RegExpNode(on_success->zone()), on_success_(on_success) { } |
| 614 | RegExpNode* on_success() { return on_success_; } |
| 615 | void set_on_success(RegExpNode* node) { on_success_ = node; } |
| 616 | virtual RegExpNode* FilterOneByte(int depth, bool ignore_case); |
| 617 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 618 | BoyerMooreLookahead* bm, bool not_at_start) { |
| 619 | on_success_->FillInBMInfo(isolate, offset, budget - 1, bm, not_at_start); |
| 620 | if (offset == 0) set_bm_info(not_at_start, bm); |
| 621 | } |
| 622 | |
| 623 | protected: |
| 624 | RegExpNode* FilterSuccessor(int depth, bool ignore_case); |
| 625 | |
| 626 | private: |
| 627 | RegExpNode* on_success_; |
| 628 | }; |
| 629 | |
| 630 | |
| 631 | class ActionNode: public SeqRegExpNode { |
| 632 | public: |
| 633 | enum ActionType { |
| 634 | SET_REGISTER, |
| 635 | INCREMENT_REGISTER, |
| 636 | STORE_POSITION, |
| 637 | BEGIN_SUBMATCH, |
| 638 | POSITIVE_SUBMATCH_SUCCESS, |
| 639 | EMPTY_MATCH_CHECK, |
| 640 | CLEAR_CAPTURES |
| 641 | }; |
| 642 | static ActionNode* SetRegister(int reg, int val, RegExpNode* on_success); |
| 643 | static ActionNode* IncrementRegister(int reg, RegExpNode* on_success); |
| 644 | static ActionNode* StorePosition(int reg, |
| 645 | bool is_capture, |
| 646 | RegExpNode* on_success); |
| 647 | static ActionNode* ClearCaptures(Interval range, RegExpNode* on_success); |
| 648 | static ActionNode* BeginSubmatch(int stack_pointer_reg, |
| 649 | int position_reg, |
| 650 | RegExpNode* on_success); |
| 651 | static ActionNode* PositiveSubmatchSuccess(int stack_pointer_reg, |
| 652 | int restore_reg, |
| 653 | int clear_capture_count, |
| 654 | int clear_capture_from, |
| 655 | RegExpNode* on_success); |
| 656 | static ActionNode* EmptyMatchCheck(int start_register, |
| 657 | int repetition_register, |
| 658 | int repetition_limit, |
| 659 | RegExpNode* on_success); |
| 660 | virtual void Accept(NodeVisitor* visitor); |
| 661 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 662 | virtual int EatsAtLeast(int still_to_find, int budget, bool not_at_start); |
| 663 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 664 | RegExpCompiler* compiler, |
| 665 | int filled_in, |
| 666 | bool not_at_start) { |
| 667 | return on_success()->GetQuickCheckDetails( |
| 668 | details, compiler, filled_in, not_at_start); |
| 669 | } |
| 670 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 671 | BoyerMooreLookahead* bm, bool not_at_start); |
| 672 | ActionType action_type() { return action_type_; } |
| 673 | // TODO(erikcorry): We should allow some action nodes in greedy loops. |
| 674 | virtual int GreedyLoopTextLength() { return kNodeIsTooComplexForGreedyLoops; } |
| 675 | |
| 676 | private: |
| 677 | union { |
| 678 | struct { |
| 679 | int reg; |
| 680 | int value; |
| 681 | } u_store_register; |
| 682 | struct { |
| 683 | int reg; |
| 684 | } u_increment_register; |
| 685 | struct { |
| 686 | int reg; |
| 687 | bool is_capture; |
| 688 | } u_position_register; |
| 689 | struct { |
| 690 | int stack_pointer_register; |
| 691 | int current_position_register; |
| 692 | int clear_register_count; |
| 693 | int clear_register_from; |
| 694 | } u_submatch; |
| 695 | struct { |
| 696 | int start_register; |
| 697 | int repetition_register; |
| 698 | int repetition_limit; |
| 699 | } u_empty_match_check; |
| 700 | struct { |
| 701 | int range_from; |
| 702 | int range_to; |
| 703 | } u_clear_captures; |
| 704 | } data_; |
| 705 | ActionNode(ActionType action_type, RegExpNode* on_success) |
| 706 | : SeqRegExpNode(on_success), |
| 707 | action_type_(action_type) { } |
| 708 | ActionType action_type_; |
| 709 | friend class DotPrinter; |
| 710 | }; |
| 711 | |
| 712 | |
| 713 | class TextNode: public SeqRegExpNode { |
| 714 | public: |
| 715 | TextNode(ZoneList<TextElement>* elms, bool read_backward, |
| 716 | RegExpNode* on_success) |
| 717 | : SeqRegExpNode(on_success), elms_(elms), read_backward_(read_backward) {} |
| 718 | TextNode(RegExpCharacterClass* that, bool read_backward, |
| 719 | RegExpNode* on_success) |
| 720 | : SeqRegExpNode(on_success), |
| 721 | elms_(new (zone()) ZoneList<TextElement>(1, zone())), |
| 722 | read_backward_(read_backward) { |
| 723 | elms_->Add(TextElement::CharClass(that), zone()); |
| 724 | } |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 725 | // Create TextNode for a single character class for the given ranges. |
| 726 | static TextNode* CreateForCharacterRanges(Zone* zone, |
| 727 | ZoneList<CharacterRange>* ranges, |
| 728 | bool read_backward, |
| 729 | RegExpNode* on_success); |
| 730 | // Create TextNode for a surrogate pair with a range given for the |
| 731 | // lead and the trail surrogate each. |
| 732 | static TextNode* CreateForSurrogatePair(Zone* zone, CharacterRange lead, |
| 733 | CharacterRange trail, |
| 734 | bool read_backward, |
| 735 | RegExpNode* on_success); |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 736 | virtual void Accept(NodeVisitor* visitor); |
| 737 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 738 | virtual int EatsAtLeast(int still_to_find, int budget, bool not_at_start); |
| 739 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 740 | RegExpCompiler* compiler, |
| 741 | int characters_filled_in, |
| 742 | bool not_at_start); |
| 743 | ZoneList<TextElement>* elements() { return elms_; } |
| 744 | bool read_backward() { return read_backward_; } |
| 745 | void MakeCaseIndependent(Isolate* isolate, bool is_one_byte); |
| 746 | virtual int GreedyLoopTextLength(); |
| 747 | virtual RegExpNode* GetSuccessorOfOmnivorousTextNode( |
| 748 | RegExpCompiler* compiler); |
| 749 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 750 | BoyerMooreLookahead* bm, bool not_at_start); |
| 751 | void CalculateOffsets(); |
| 752 | virtual RegExpNode* FilterOneByte(int depth, bool ignore_case); |
| 753 | |
| 754 | private: |
| 755 | enum TextEmitPassType { |
| 756 | NON_LATIN1_MATCH, // Check for characters that can't match. |
| 757 | SIMPLE_CHARACTER_MATCH, // Case-dependent single character check. |
| 758 | NON_LETTER_CHARACTER_MATCH, // Check characters that have no case equivs. |
| 759 | CASE_CHARACTER_MATCH, // Case-independent single character check. |
| 760 | CHARACTER_CLASS_MATCH // Character class. |
| 761 | }; |
| 762 | static bool SkipPass(int pass, bool ignore_case); |
| 763 | static const int kFirstRealPass = SIMPLE_CHARACTER_MATCH; |
| 764 | static const int kLastPass = CHARACTER_CLASS_MATCH; |
| 765 | void TextEmitPass(RegExpCompiler* compiler, |
| 766 | TextEmitPassType pass, |
| 767 | bool preloaded, |
| 768 | Trace* trace, |
| 769 | bool first_element_checked, |
| 770 | int* checked_up_to); |
| 771 | int Length(); |
| 772 | ZoneList<TextElement>* elms_; |
| 773 | bool read_backward_; |
| 774 | }; |
| 775 | |
| 776 | |
| 777 | class AssertionNode: public SeqRegExpNode { |
| 778 | public: |
| 779 | enum AssertionType { |
| 780 | AT_END, |
| 781 | AT_START, |
| 782 | AT_BOUNDARY, |
| 783 | AT_NON_BOUNDARY, |
| 784 | AFTER_NEWLINE |
| 785 | }; |
| 786 | static AssertionNode* AtEnd(RegExpNode* on_success) { |
| 787 | return new(on_success->zone()) AssertionNode(AT_END, on_success); |
| 788 | } |
| 789 | static AssertionNode* AtStart(RegExpNode* on_success) { |
| 790 | return new(on_success->zone()) AssertionNode(AT_START, on_success); |
| 791 | } |
| 792 | static AssertionNode* AtBoundary(RegExpNode* on_success) { |
| 793 | return new(on_success->zone()) AssertionNode(AT_BOUNDARY, on_success); |
| 794 | } |
| 795 | static AssertionNode* AtNonBoundary(RegExpNode* on_success) { |
| 796 | return new(on_success->zone()) AssertionNode(AT_NON_BOUNDARY, on_success); |
| 797 | } |
| 798 | static AssertionNode* AfterNewline(RegExpNode* on_success) { |
| 799 | return new(on_success->zone()) AssertionNode(AFTER_NEWLINE, on_success); |
| 800 | } |
| 801 | virtual void Accept(NodeVisitor* visitor); |
| 802 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 803 | virtual int EatsAtLeast(int still_to_find, int budget, bool not_at_start); |
| 804 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 805 | RegExpCompiler* compiler, |
| 806 | int filled_in, |
| 807 | bool not_at_start); |
| 808 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 809 | BoyerMooreLookahead* bm, bool not_at_start); |
| 810 | AssertionType assertion_type() { return assertion_type_; } |
| 811 | |
| 812 | private: |
| 813 | void EmitBoundaryCheck(RegExpCompiler* compiler, Trace* trace); |
| 814 | enum IfPrevious { kIsNonWord, kIsWord }; |
| 815 | void BacktrackIfPrevious(RegExpCompiler* compiler, |
| 816 | Trace* trace, |
| 817 | IfPrevious backtrack_if_previous); |
| 818 | AssertionNode(AssertionType t, RegExpNode* on_success) |
| 819 | : SeqRegExpNode(on_success), assertion_type_(t) { } |
| 820 | AssertionType assertion_type_; |
| 821 | }; |
| 822 | |
| 823 | |
| 824 | class BackReferenceNode: public SeqRegExpNode { |
| 825 | public: |
| 826 | BackReferenceNode(int start_reg, int end_reg, bool read_backward, |
| 827 | RegExpNode* on_success) |
| 828 | : SeqRegExpNode(on_success), |
| 829 | start_reg_(start_reg), |
| 830 | end_reg_(end_reg), |
| 831 | read_backward_(read_backward) {} |
| 832 | virtual void Accept(NodeVisitor* visitor); |
| 833 | int start_register() { return start_reg_; } |
| 834 | int end_register() { return end_reg_; } |
| 835 | bool read_backward() { return read_backward_; } |
| 836 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 837 | virtual int EatsAtLeast(int still_to_find, |
| 838 | int recursion_depth, |
| 839 | bool not_at_start); |
| 840 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 841 | RegExpCompiler* compiler, |
| 842 | int characters_filled_in, |
| 843 | bool not_at_start) { |
| 844 | return; |
| 845 | } |
| 846 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 847 | BoyerMooreLookahead* bm, bool not_at_start); |
| 848 | |
| 849 | private: |
| 850 | int start_reg_; |
| 851 | int end_reg_; |
| 852 | bool read_backward_; |
| 853 | }; |
| 854 | |
| 855 | |
| 856 | class EndNode: public RegExpNode { |
| 857 | public: |
| 858 | enum Action { ACCEPT, BACKTRACK, NEGATIVE_SUBMATCH_SUCCESS }; |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 859 | EndNode(Action action, Zone* zone) : RegExpNode(zone), action_(action) {} |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 860 | virtual void Accept(NodeVisitor* visitor); |
| 861 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 862 | virtual int EatsAtLeast(int still_to_find, |
| 863 | int recursion_depth, |
| 864 | bool not_at_start) { return 0; } |
| 865 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 866 | RegExpCompiler* compiler, |
| 867 | int characters_filled_in, |
| 868 | bool not_at_start) { |
| 869 | // Returning 0 from EatsAtLeast should ensure we never get here. |
| 870 | UNREACHABLE(); |
| 871 | } |
| 872 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 873 | BoyerMooreLookahead* bm, bool not_at_start) { |
| 874 | // Returning 0 from EatsAtLeast should ensure we never get here. |
| 875 | UNREACHABLE(); |
| 876 | } |
| 877 | |
| 878 | private: |
| 879 | Action action_; |
| 880 | }; |
| 881 | |
| 882 | |
| 883 | class NegativeSubmatchSuccess: public EndNode { |
| 884 | public: |
| 885 | NegativeSubmatchSuccess(int stack_pointer_reg, |
| 886 | int position_reg, |
| 887 | int clear_capture_count, |
| 888 | int clear_capture_start, |
| 889 | Zone* zone) |
| 890 | : EndNode(NEGATIVE_SUBMATCH_SUCCESS, zone), |
| 891 | stack_pointer_register_(stack_pointer_reg), |
| 892 | current_position_register_(position_reg), |
| 893 | clear_capture_count_(clear_capture_count), |
| 894 | clear_capture_start_(clear_capture_start) { } |
| 895 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 896 | |
| 897 | private: |
| 898 | int stack_pointer_register_; |
| 899 | int current_position_register_; |
| 900 | int clear_capture_count_; |
| 901 | int clear_capture_start_; |
| 902 | }; |
| 903 | |
| 904 | |
| 905 | class Guard: public ZoneObject { |
| 906 | public: |
| 907 | enum Relation { LT, GEQ }; |
| 908 | Guard(int reg, Relation op, int value) |
| 909 | : reg_(reg), |
| 910 | op_(op), |
| 911 | value_(value) { } |
| 912 | int reg() { return reg_; } |
| 913 | Relation op() { return op_; } |
| 914 | int value() { return value_; } |
| 915 | |
| 916 | private: |
| 917 | int reg_; |
| 918 | Relation op_; |
| 919 | int value_; |
| 920 | }; |
| 921 | |
| 922 | |
| 923 | class GuardedAlternative { |
| 924 | public: |
| 925 | explicit GuardedAlternative(RegExpNode* node) : node_(node), guards_(NULL) { } |
| 926 | void AddGuard(Guard* guard, Zone* zone); |
| 927 | RegExpNode* node() { return node_; } |
| 928 | void set_node(RegExpNode* node) { node_ = node; } |
| 929 | ZoneList<Guard*>* guards() { return guards_; } |
| 930 | |
| 931 | private: |
| 932 | RegExpNode* node_; |
| 933 | ZoneList<Guard*>* guards_; |
| 934 | }; |
| 935 | |
| 936 | |
| 937 | class AlternativeGeneration; |
| 938 | |
| 939 | |
| 940 | class ChoiceNode: public RegExpNode { |
| 941 | public: |
| 942 | explicit ChoiceNode(int expected_size, Zone* zone) |
| 943 | : RegExpNode(zone), |
| 944 | alternatives_(new(zone) |
| 945 | ZoneList<GuardedAlternative>(expected_size, zone)), |
| 946 | table_(NULL), |
| 947 | not_at_start_(false), |
| 948 | being_calculated_(false) { } |
| 949 | virtual void Accept(NodeVisitor* visitor); |
| 950 | void AddAlternative(GuardedAlternative node) { |
| 951 | alternatives()->Add(node, zone()); |
| 952 | } |
| 953 | ZoneList<GuardedAlternative>* alternatives() { return alternatives_; } |
| 954 | DispatchTable* GetTable(bool ignore_case); |
| 955 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 956 | virtual int EatsAtLeast(int still_to_find, int budget, bool not_at_start); |
| 957 | int EatsAtLeastHelper(int still_to_find, |
| 958 | int budget, |
| 959 | RegExpNode* ignore_this_node, |
| 960 | bool not_at_start); |
| 961 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 962 | RegExpCompiler* compiler, |
| 963 | int characters_filled_in, |
| 964 | bool not_at_start); |
| 965 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 966 | BoyerMooreLookahead* bm, bool not_at_start); |
| 967 | |
| 968 | bool being_calculated() { return being_calculated_; } |
| 969 | bool not_at_start() { return not_at_start_; } |
| 970 | void set_not_at_start() { not_at_start_ = true; } |
| 971 | void set_being_calculated(bool b) { being_calculated_ = b; } |
| 972 | virtual bool try_to_emit_quick_check_for_alternative(bool is_first) { |
| 973 | return true; |
| 974 | } |
| 975 | virtual RegExpNode* FilterOneByte(int depth, bool ignore_case); |
| 976 | virtual bool read_backward() { return false; } |
| 977 | |
| 978 | protected: |
| 979 | int GreedyLoopTextLengthForAlternative(GuardedAlternative* alternative); |
| 980 | ZoneList<GuardedAlternative>* alternatives_; |
| 981 | |
| 982 | private: |
| 983 | friend class DispatchTableConstructor; |
| 984 | friend class Analysis; |
| 985 | void GenerateGuard(RegExpMacroAssembler* macro_assembler, |
| 986 | Guard* guard, |
| 987 | Trace* trace); |
| 988 | int CalculatePreloadCharacters(RegExpCompiler* compiler, int eats_at_least); |
| 989 | void EmitOutOfLineContinuation(RegExpCompiler* compiler, |
| 990 | Trace* trace, |
| 991 | GuardedAlternative alternative, |
| 992 | AlternativeGeneration* alt_gen, |
| 993 | int preload_characters, |
| 994 | bool next_expects_preload); |
| 995 | void SetUpPreLoad(RegExpCompiler* compiler, |
| 996 | Trace* current_trace, |
| 997 | PreloadState* preloads); |
| 998 | void AssertGuardsMentionRegisters(Trace* trace); |
| 999 | int EmitOptimizedUnanchoredSearch(RegExpCompiler* compiler, Trace* trace); |
| 1000 | Trace* EmitGreedyLoop(RegExpCompiler* compiler, |
| 1001 | Trace* trace, |
| 1002 | AlternativeGenerationList* alt_gens, |
| 1003 | PreloadState* preloads, |
| 1004 | GreedyLoopState* greedy_loop_state, |
| 1005 | int text_length); |
| 1006 | void EmitChoices(RegExpCompiler* compiler, |
| 1007 | AlternativeGenerationList* alt_gens, |
| 1008 | int first_choice, |
| 1009 | Trace* trace, |
| 1010 | PreloadState* preloads); |
| 1011 | DispatchTable* table_; |
| 1012 | // If true, this node is never checked at the start of the input. |
| 1013 | // Allows a new trace to start with at_start() set to false. |
| 1014 | bool not_at_start_; |
| 1015 | bool being_calculated_; |
| 1016 | }; |
| 1017 | |
| 1018 | |
| 1019 | class NegativeLookaroundChoiceNode : public ChoiceNode { |
| 1020 | public: |
| 1021 | explicit NegativeLookaroundChoiceNode(GuardedAlternative this_must_fail, |
| 1022 | GuardedAlternative then_do_this, |
| 1023 | Zone* zone) |
| 1024 | : ChoiceNode(2, zone) { |
| 1025 | AddAlternative(this_must_fail); |
| 1026 | AddAlternative(then_do_this); |
| 1027 | } |
| 1028 | virtual int EatsAtLeast(int still_to_find, int budget, bool not_at_start); |
| 1029 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 1030 | RegExpCompiler* compiler, |
| 1031 | int characters_filled_in, |
| 1032 | bool not_at_start); |
| 1033 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 1034 | BoyerMooreLookahead* bm, bool not_at_start) { |
| 1035 | alternatives_->at(1).node()->FillInBMInfo(isolate, offset, budget - 1, bm, |
| 1036 | not_at_start); |
| 1037 | if (offset == 0) set_bm_info(not_at_start, bm); |
| 1038 | } |
| 1039 | // For a negative lookahead we don't emit the quick check for the |
| 1040 | // alternative that is expected to fail. This is because quick check code |
| 1041 | // starts by loading enough characters for the alternative that takes fewest |
| 1042 | // characters, but on a negative lookahead the negative branch did not take |
| 1043 | // part in that calculation (EatsAtLeast) so the assumptions don't hold. |
| 1044 | virtual bool try_to_emit_quick_check_for_alternative(bool is_first) { |
| 1045 | return !is_first; |
| 1046 | } |
| 1047 | virtual RegExpNode* FilterOneByte(int depth, bool ignore_case); |
| 1048 | }; |
| 1049 | |
| 1050 | |
| 1051 | class LoopChoiceNode: public ChoiceNode { |
| 1052 | public: |
| 1053 | LoopChoiceNode(bool body_can_be_zero_length, bool read_backward, Zone* zone) |
| 1054 | : ChoiceNode(2, zone), |
| 1055 | loop_node_(NULL), |
| 1056 | continue_node_(NULL), |
| 1057 | body_can_be_zero_length_(body_can_be_zero_length), |
| 1058 | read_backward_(read_backward) {} |
| 1059 | void AddLoopAlternative(GuardedAlternative alt); |
| 1060 | void AddContinueAlternative(GuardedAlternative alt); |
| 1061 | virtual void Emit(RegExpCompiler* compiler, Trace* trace); |
| 1062 | virtual int EatsAtLeast(int still_to_find, int budget, bool not_at_start); |
| 1063 | virtual void GetQuickCheckDetails(QuickCheckDetails* details, |
| 1064 | RegExpCompiler* compiler, |
| 1065 | int characters_filled_in, |
| 1066 | bool not_at_start); |
| 1067 | virtual void FillInBMInfo(Isolate* isolate, int offset, int budget, |
| 1068 | BoyerMooreLookahead* bm, bool not_at_start); |
| 1069 | RegExpNode* loop_node() { return loop_node_; } |
| 1070 | RegExpNode* continue_node() { return continue_node_; } |
| 1071 | bool body_can_be_zero_length() { return body_can_be_zero_length_; } |
| 1072 | virtual bool read_backward() { return read_backward_; } |
| 1073 | virtual void Accept(NodeVisitor* visitor); |
| 1074 | virtual RegExpNode* FilterOneByte(int depth, bool ignore_case); |
| 1075 | |
| 1076 | private: |
| 1077 | // AddAlternative is made private for loop nodes because alternatives |
| 1078 | // should not be added freely, we need to keep track of which node |
| 1079 | // goes back to the node itself. |
| 1080 | void AddAlternative(GuardedAlternative node) { |
| 1081 | ChoiceNode::AddAlternative(node); |
| 1082 | } |
| 1083 | |
| 1084 | RegExpNode* loop_node_; |
| 1085 | RegExpNode* continue_node_; |
| 1086 | bool body_can_be_zero_length_; |
| 1087 | bool read_backward_; |
| 1088 | }; |
| 1089 | |
| 1090 | |
| 1091 | // Improve the speed that we scan for an initial point where a non-anchored |
| 1092 | // regexp can match by using a Boyer-Moore-like table. This is done by |
| 1093 | // identifying non-greedy non-capturing loops in the nodes that eat any |
| 1094 | // character one at a time. For example in the middle of the regexp |
| 1095 | // /foo[\s\S]*?bar/ we find such a loop. There is also such a loop implicitly |
| 1096 | // inserted at the start of any non-anchored regexp. |
| 1097 | // |
| 1098 | // When we have found such a loop we look ahead in the nodes to find the set of |
| 1099 | // characters that can come at given distances. For example for the regexp |
| 1100 | // /.?foo/ we know that there are at least 3 characters ahead of us, and the |
| 1101 | // sets of characters that can occur are [any, [f, o], [o]]. We find a range in |
| 1102 | // the lookahead info where the set of characters is reasonably constrained. In |
| 1103 | // our example this is from index 1 to 2 (0 is not constrained). We can now |
| 1104 | // look 3 characters ahead and if we don't find one of [f, o] (the union of |
| 1105 | // [f, o] and [o]) then we can skip forwards by the range size (in this case 2). |
| 1106 | // |
| 1107 | // For Unicode input strings we do the same, but modulo 128. |
| 1108 | // |
| 1109 | // We also look at the first string fed to the regexp and use that to get a hint |
| 1110 | // of the character frequencies in the inputs. This affects the assessment of |
| 1111 | // whether the set of characters is 'reasonably constrained'. |
| 1112 | // |
| 1113 | // We also have another lookahead mechanism (called quick check in the code), |
| 1114 | // which uses a wide load of multiple characters followed by a mask and compare |
| 1115 | // to determine whether a match is possible at this point. |
| 1116 | enum ContainedInLattice { |
| 1117 | kNotYet = 0, |
| 1118 | kLatticeIn = 1, |
| 1119 | kLatticeOut = 2, |
| 1120 | kLatticeUnknown = 3 // Can also mean both in and out. |
| 1121 | }; |
| 1122 | |
| 1123 | |
| 1124 | inline ContainedInLattice Combine(ContainedInLattice a, ContainedInLattice b) { |
| 1125 | return static_cast<ContainedInLattice>(a | b); |
| 1126 | } |
| 1127 | |
| 1128 | |
| 1129 | ContainedInLattice AddRange(ContainedInLattice a, |
| 1130 | const int* ranges, |
| 1131 | int ranges_size, |
| 1132 | Interval new_range); |
| 1133 | |
| 1134 | |
| 1135 | class BoyerMoorePositionInfo : public ZoneObject { |
| 1136 | public: |
| 1137 | explicit BoyerMoorePositionInfo(Zone* zone) |
| 1138 | : map_(new(zone) ZoneList<bool>(kMapSize, zone)), |
| 1139 | map_count_(0), |
| 1140 | w_(kNotYet), |
| 1141 | s_(kNotYet), |
| 1142 | d_(kNotYet), |
| 1143 | surrogate_(kNotYet) { |
| 1144 | for (int i = 0; i < kMapSize; i++) { |
| 1145 | map_->Add(false, zone); |
| 1146 | } |
| 1147 | } |
| 1148 | |
| 1149 | bool& at(int i) { return map_->at(i); } |
| 1150 | |
| 1151 | static const int kMapSize = 128; |
| 1152 | static const int kMask = kMapSize - 1; |
| 1153 | |
| 1154 | int map_count() const { return map_count_; } |
| 1155 | |
| 1156 | void Set(int character); |
| 1157 | void SetInterval(const Interval& interval); |
| 1158 | void SetAll(); |
| 1159 | bool is_non_word() { return w_ == kLatticeOut; } |
| 1160 | bool is_word() { return w_ == kLatticeIn; } |
| 1161 | |
| 1162 | private: |
| 1163 | ZoneList<bool>* map_; |
| 1164 | int map_count_; // Number of set bits in the map. |
| 1165 | ContainedInLattice w_; // The \w character class. |
| 1166 | ContainedInLattice s_; // The \s character class. |
| 1167 | ContainedInLattice d_; // The \d character class. |
| 1168 | ContainedInLattice surrogate_; // Surrogate UTF-16 code units. |
| 1169 | }; |
| 1170 | |
| 1171 | |
| 1172 | class BoyerMooreLookahead : public ZoneObject { |
| 1173 | public: |
| 1174 | BoyerMooreLookahead(int length, RegExpCompiler* compiler, Zone* zone); |
| 1175 | |
| 1176 | int length() { return length_; } |
| 1177 | int max_char() { return max_char_; } |
| 1178 | RegExpCompiler* compiler() { return compiler_; } |
| 1179 | |
| 1180 | int Count(int map_number) { |
| 1181 | return bitmaps_->at(map_number)->map_count(); |
| 1182 | } |
| 1183 | |
| 1184 | BoyerMoorePositionInfo* at(int i) { return bitmaps_->at(i); } |
| 1185 | |
| 1186 | void Set(int map_number, int character) { |
| 1187 | if (character > max_char_) return; |
| 1188 | BoyerMoorePositionInfo* info = bitmaps_->at(map_number); |
| 1189 | info->Set(character); |
| 1190 | } |
| 1191 | |
| 1192 | void SetInterval(int map_number, const Interval& interval) { |
| 1193 | if (interval.from() > max_char_) return; |
| 1194 | BoyerMoorePositionInfo* info = bitmaps_->at(map_number); |
| 1195 | if (interval.to() > max_char_) { |
| 1196 | info->SetInterval(Interval(interval.from(), max_char_)); |
| 1197 | } else { |
| 1198 | info->SetInterval(interval); |
| 1199 | } |
| 1200 | } |
| 1201 | |
| 1202 | void SetAll(int map_number) { |
| 1203 | bitmaps_->at(map_number)->SetAll(); |
| 1204 | } |
| 1205 | |
| 1206 | void SetRest(int from_map) { |
| 1207 | for (int i = from_map; i < length_; i++) SetAll(i); |
| 1208 | } |
| 1209 | void EmitSkipInstructions(RegExpMacroAssembler* masm); |
| 1210 | |
| 1211 | private: |
| 1212 | // This is the value obtained by EatsAtLeast. If we do not have at least this |
| 1213 | // many characters left in the sample string then the match is bound to fail. |
| 1214 | // Therefore it is OK to read a character this far ahead of the current match |
| 1215 | // point. |
| 1216 | int length_; |
| 1217 | RegExpCompiler* compiler_; |
| 1218 | // 0xff for Latin1, 0xffff for UTF-16. |
| 1219 | int max_char_; |
| 1220 | ZoneList<BoyerMoorePositionInfo*>* bitmaps_; |
| 1221 | |
| 1222 | int GetSkipTable(int min_lookahead, |
| 1223 | int max_lookahead, |
| 1224 | Handle<ByteArray> boolean_skip_table); |
| 1225 | bool FindWorthwhileInterval(int* from, int* to); |
| 1226 | int FindBestInterval( |
| 1227 | int max_number_of_chars, int old_biggest_points, int* from, int* to); |
| 1228 | }; |
| 1229 | |
| 1230 | |
| 1231 | // There are many ways to generate code for a node. This class encapsulates |
| 1232 | // the current way we should be generating. In other words it encapsulates |
| 1233 | // the current state of the code generator. The effect of this is that we |
| 1234 | // generate code for paths that the matcher can take through the regular |
| 1235 | // expression. A given node in the regexp can be code-generated several times |
| 1236 | // as it can be part of several traces. For example for the regexp: |
| 1237 | // /foo(bar|ip)baz/ the code to match baz will be generated twice, once as part |
| 1238 | // of the foo-bar-baz trace and once as part of the foo-ip-baz trace. The code |
| 1239 | // to match foo is generated only once (the traces have a common prefix). The |
| 1240 | // code to store the capture is deferred and generated (twice) after the places |
| 1241 | // where baz has been matched. |
| 1242 | class Trace { |
| 1243 | public: |
| 1244 | // A value for a property that is either known to be true, know to be false, |
| 1245 | // or not known. |
| 1246 | enum TriBool { |
| 1247 | UNKNOWN = -1, FALSE_VALUE = 0, TRUE_VALUE = 1 |
| 1248 | }; |
| 1249 | |
| 1250 | class DeferredAction { |
| 1251 | public: |
| 1252 | DeferredAction(ActionNode::ActionType action_type, int reg) |
| 1253 | : action_type_(action_type), reg_(reg), next_(NULL) { } |
| 1254 | DeferredAction* next() { return next_; } |
| 1255 | bool Mentions(int reg); |
| 1256 | int reg() { return reg_; } |
| 1257 | ActionNode::ActionType action_type() { return action_type_; } |
| 1258 | private: |
| 1259 | ActionNode::ActionType action_type_; |
| 1260 | int reg_; |
| 1261 | DeferredAction* next_; |
| 1262 | friend class Trace; |
| 1263 | }; |
| 1264 | |
| 1265 | class DeferredCapture : public DeferredAction { |
| 1266 | public: |
| 1267 | DeferredCapture(int reg, bool is_capture, Trace* trace) |
| 1268 | : DeferredAction(ActionNode::STORE_POSITION, reg), |
| 1269 | cp_offset_(trace->cp_offset()), |
| 1270 | is_capture_(is_capture) { } |
| 1271 | int cp_offset() { return cp_offset_; } |
| 1272 | bool is_capture() { return is_capture_; } |
| 1273 | private: |
| 1274 | int cp_offset_; |
| 1275 | bool is_capture_; |
| 1276 | void set_cp_offset(int cp_offset) { cp_offset_ = cp_offset; } |
| 1277 | }; |
| 1278 | |
| 1279 | class DeferredSetRegister : public DeferredAction { |
| 1280 | public: |
| 1281 | DeferredSetRegister(int reg, int value) |
| 1282 | : DeferredAction(ActionNode::SET_REGISTER, reg), |
| 1283 | value_(value) { } |
| 1284 | int value() { return value_; } |
| 1285 | private: |
| 1286 | int value_; |
| 1287 | }; |
| 1288 | |
| 1289 | class DeferredClearCaptures : public DeferredAction { |
| 1290 | public: |
| 1291 | explicit DeferredClearCaptures(Interval range) |
| 1292 | : DeferredAction(ActionNode::CLEAR_CAPTURES, -1), |
| 1293 | range_(range) { } |
| 1294 | Interval range() { return range_; } |
| 1295 | private: |
| 1296 | Interval range_; |
| 1297 | }; |
| 1298 | |
| 1299 | class DeferredIncrementRegister : public DeferredAction { |
| 1300 | public: |
| 1301 | explicit DeferredIncrementRegister(int reg) |
| 1302 | : DeferredAction(ActionNode::INCREMENT_REGISTER, reg) { } |
| 1303 | }; |
| 1304 | |
| 1305 | Trace() |
| 1306 | : cp_offset_(0), |
| 1307 | actions_(NULL), |
| 1308 | backtrack_(NULL), |
| 1309 | stop_node_(NULL), |
| 1310 | loop_label_(NULL), |
| 1311 | characters_preloaded_(0), |
| 1312 | bound_checked_up_to_(0), |
| 1313 | flush_budget_(100), |
| 1314 | at_start_(UNKNOWN) { } |
| 1315 | |
| 1316 | // End the trace. This involves flushing the deferred actions in the trace |
| 1317 | // and pushing a backtrack location onto the backtrack stack. Once this is |
| 1318 | // done we can start a new trace or go to one that has already been |
| 1319 | // generated. |
| 1320 | void Flush(RegExpCompiler* compiler, RegExpNode* successor); |
| 1321 | int cp_offset() { return cp_offset_; } |
| 1322 | DeferredAction* actions() { return actions_; } |
| 1323 | // A trivial trace is one that has no deferred actions or other state that |
| 1324 | // affects the assumptions used when generating code. There is no recorded |
| 1325 | // backtrack location in a trivial trace, so with a trivial trace we will |
| 1326 | // generate code that, on a failure to match, gets the backtrack location |
| 1327 | // from the backtrack stack rather than using a direct jump instruction. We |
| 1328 | // always start code generation with a trivial trace and non-trivial traces |
| 1329 | // are created as we emit code for nodes or add to the list of deferred |
| 1330 | // actions in the trace. The location of the code generated for a node using |
| 1331 | // a trivial trace is recorded in a label in the node so that gotos can be |
| 1332 | // generated to that code. |
| 1333 | bool is_trivial() { |
| 1334 | return backtrack_ == NULL && |
| 1335 | actions_ == NULL && |
| 1336 | cp_offset_ == 0 && |
| 1337 | characters_preloaded_ == 0 && |
| 1338 | bound_checked_up_to_ == 0 && |
| 1339 | quick_check_performed_.characters() == 0 && |
| 1340 | at_start_ == UNKNOWN; |
| 1341 | } |
| 1342 | TriBool at_start() { return at_start_; } |
| 1343 | void set_at_start(TriBool at_start) { at_start_ = at_start; } |
| 1344 | Label* backtrack() { return backtrack_; } |
| 1345 | Label* loop_label() { return loop_label_; } |
| 1346 | RegExpNode* stop_node() { return stop_node_; } |
| 1347 | int characters_preloaded() { return characters_preloaded_; } |
| 1348 | int bound_checked_up_to() { return bound_checked_up_to_; } |
| 1349 | int flush_budget() { return flush_budget_; } |
| 1350 | QuickCheckDetails* quick_check_performed() { return &quick_check_performed_; } |
| 1351 | bool mentions_reg(int reg); |
| 1352 | // Returns true if a deferred position store exists to the specified |
| 1353 | // register and stores the offset in the out-parameter. Otherwise |
| 1354 | // returns false. |
| 1355 | bool GetStoredPosition(int reg, int* cp_offset); |
| 1356 | // These set methods and AdvanceCurrentPositionInTrace should be used only on |
| 1357 | // new traces - the intention is that traces are immutable after creation. |
| 1358 | void add_action(DeferredAction* new_action) { |
| 1359 | DCHECK(new_action->next_ == NULL); |
| 1360 | new_action->next_ = actions_; |
| 1361 | actions_ = new_action; |
| 1362 | } |
| 1363 | void set_backtrack(Label* backtrack) { backtrack_ = backtrack; } |
| 1364 | void set_stop_node(RegExpNode* node) { stop_node_ = node; } |
| 1365 | void set_loop_label(Label* label) { loop_label_ = label; } |
| 1366 | void set_characters_preloaded(int count) { characters_preloaded_ = count; } |
| 1367 | void set_bound_checked_up_to(int to) { bound_checked_up_to_ = to; } |
| 1368 | void set_flush_budget(int to) { flush_budget_ = to; } |
| 1369 | void set_quick_check_performed(QuickCheckDetails* d) { |
| 1370 | quick_check_performed_ = *d; |
| 1371 | } |
| 1372 | void InvalidateCurrentCharacter(); |
| 1373 | void AdvanceCurrentPositionInTrace(int by, RegExpCompiler* compiler); |
| 1374 | |
| 1375 | private: |
| 1376 | int FindAffectedRegisters(OutSet* affected_registers, Zone* zone); |
| 1377 | void PerformDeferredActions(RegExpMacroAssembler* macro, |
| 1378 | int max_register, |
| 1379 | const OutSet& affected_registers, |
| 1380 | OutSet* registers_to_pop, |
| 1381 | OutSet* registers_to_clear, |
| 1382 | Zone* zone); |
| 1383 | void RestoreAffectedRegisters(RegExpMacroAssembler* macro, |
| 1384 | int max_register, |
| 1385 | const OutSet& registers_to_pop, |
| 1386 | const OutSet& registers_to_clear); |
| 1387 | int cp_offset_; |
| 1388 | DeferredAction* actions_; |
| 1389 | Label* backtrack_; |
| 1390 | RegExpNode* stop_node_; |
| 1391 | Label* loop_label_; |
| 1392 | int characters_preloaded_; |
| 1393 | int bound_checked_up_to_; |
| 1394 | QuickCheckDetails quick_check_performed_; |
| 1395 | int flush_budget_; |
| 1396 | TriBool at_start_; |
| 1397 | }; |
| 1398 | |
| 1399 | |
| 1400 | class GreedyLoopState { |
| 1401 | public: |
| 1402 | explicit GreedyLoopState(bool not_at_start); |
| 1403 | |
| 1404 | Label* label() { return &label_; } |
| 1405 | Trace* counter_backtrack_trace() { return &counter_backtrack_trace_; } |
| 1406 | |
| 1407 | private: |
| 1408 | Label label_; |
| 1409 | Trace counter_backtrack_trace_; |
| 1410 | }; |
| 1411 | |
| 1412 | |
| 1413 | struct PreloadState { |
| 1414 | static const int kEatsAtLeastNotYetInitialized = -1; |
| 1415 | bool preload_is_current_; |
| 1416 | bool preload_has_checked_bounds_; |
| 1417 | int preload_characters_; |
| 1418 | int eats_at_least_; |
| 1419 | void init() { |
| 1420 | eats_at_least_ = kEatsAtLeastNotYetInitialized; |
| 1421 | } |
| 1422 | }; |
| 1423 | |
| 1424 | |
| 1425 | class NodeVisitor { |
| 1426 | public: |
| 1427 | virtual ~NodeVisitor() { } |
| 1428 | #define DECLARE_VISIT(Type) \ |
| 1429 | virtual void Visit##Type(Type##Node* that) = 0; |
| 1430 | FOR_EACH_NODE_TYPE(DECLARE_VISIT) |
| 1431 | #undef DECLARE_VISIT |
| 1432 | virtual void VisitLoopChoice(LoopChoiceNode* that) { VisitChoice(that); } |
| 1433 | }; |
| 1434 | |
| 1435 | |
| 1436 | // Node visitor used to add the start set of the alternatives to the |
| 1437 | // dispatch table of a choice node. |
| 1438 | class DispatchTableConstructor: public NodeVisitor { |
| 1439 | public: |
| 1440 | DispatchTableConstructor(DispatchTable* table, bool ignore_case, |
| 1441 | Zone* zone) |
| 1442 | : table_(table), |
| 1443 | choice_index_(-1), |
| 1444 | ignore_case_(ignore_case), |
| 1445 | zone_(zone) { } |
| 1446 | |
| 1447 | void BuildTable(ChoiceNode* node); |
| 1448 | |
| 1449 | void AddRange(CharacterRange range) { |
| 1450 | table()->AddRange(range, choice_index_, zone_); |
| 1451 | } |
| 1452 | |
| 1453 | void AddInverse(ZoneList<CharacterRange>* ranges); |
| 1454 | |
| 1455 | #define DECLARE_VISIT(Type) \ |
| 1456 | virtual void Visit##Type(Type##Node* that); |
| 1457 | FOR_EACH_NODE_TYPE(DECLARE_VISIT) |
| 1458 | #undef DECLARE_VISIT |
| 1459 | |
| 1460 | DispatchTable* table() { return table_; } |
| 1461 | void set_choice_index(int value) { choice_index_ = value; } |
| 1462 | |
| 1463 | protected: |
| 1464 | DispatchTable* table_; |
| 1465 | int choice_index_; |
| 1466 | bool ignore_case_; |
| 1467 | Zone* zone_; |
| 1468 | }; |
| 1469 | |
| 1470 | |
| 1471 | // Assertion propagation moves information about assertions such as |
| 1472 | // \b to the affected nodes. For instance, in /.\b./ information must |
| 1473 | // be propagated to the first '.' that whatever follows needs to know |
| 1474 | // if it matched a word or a non-word, and to the second '.' that it |
| 1475 | // has to check if it succeeds a word or non-word. In this case the |
| 1476 | // result will be something like: |
| 1477 | // |
| 1478 | // +-------+ +------------+ |
| 1479 | // | . | | . | |
| 1480 | // +-------+ ---> +------------+ |
| 1481 | // | word? | | check word | |
| 1482 | // +-------+ +------------+ |
| 1483 | class Analysis: public NodeVisitor { |
| 1484 | public: |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 1485 | Analysis(Isolate* isolate, JSRegExp::Flags flags, bool is_one_byte) |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1486 | : isolate_(isolate), |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 1487 | flags_(flags), |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1488 | is_one_byte_(is_one_byte), |
| 1489 | error_message_(NULL) {} |
| 1490 | void EnsureAnalyzed(RegExpNode* node); |
| 1491 | |
| 1492 | #define DECLARE_VISIT(Type) \ |
| 1493 | virtual void Visit##Type(Type##Node* that); |
| 1494 | FOR_EACH_NODE_TYPE(DECLARE_VISIT) |
| 1495 | #undef DECLARE_VISIT |
| 1496 | virtual void VisitLoopChoice(LoopChoiceNode* that); |
| 1497 | |
| 1498 | bool has_failed() { return error_message_ != NULL; } |
| 1499 | const char* error_message() { |
| 1500 | DCHECK(error_message_ != NULL); |
| 1501 | return error_message_; |
| 1502 | } |
| 1503 | void fail(const char* error_message) { |
| 1504 | error_message_ = error_message; |
| 1505 | } |
| 1506 | |
| 1507 | Isolate* isolate() const { return isolate_; } |
| 1508 | |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 1509 | bool ignore_case() const { return (flags_ & JSRegExp::kIgnoreCase) != 0; } |
| 1510 | bool unicode() const { return (flags_ & JSRegExp::kUnicode) != 0; } |
| 1511 | |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1512 | private: |
| 1513 | Isolate* isolate_; |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 1514 | JSRegExp::Flags flags_; |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1515 | bool is_one_byte_; |
| 1516 | const char* error_message_; |
| 1517 | |
| 1518 | DISALLOW_IMPLICIT_CONSTRUCTORS(Analysis); |
| 1519 | }; |
| 1520 | |
| 1521 | |
| 1522 | struct RegExpCompileData { |
| 1523 | RegExpCompileData() |
| 1524 | : tree(NULL), |
| 1525 | node(NULL), |
| 1526 | simple(true), |
| 1527 | contains_anchor(false), |
| 1528 | capture_count(0) { } |
| 1529 | RegExpTree* tree; |
| 1530 | RegExpNode* node; |
| 1531 | bool simple; |
| 1532 | bool contains_anchor; |
| 1533 | Handle<String> error; |
| 1534 | int capture_count; |
| 1535 | }; |
| 1536 | |
| 1537 | |
| 1538 | class RegExpEngine: public AllStatic { |
| 1539 | public: |
| 1540 | struct CompilationResult { |
| 1541 | CompilationResult(Isolate* isolate, const char* error_message) |
| 1542 | : error_message(error_message), |
| 1543 | code(isolate->heap()->the_hole_value()), |
| 1544 | num_registers(0) {} |
| 1545 | CompilationResult(Object* code, int registers) |
| 1546 | : error_message(NULL), code(code), num_registers(registers) {} |
| 1547 | const char* error_message; |
| 1548 | Object* code; |
| 1549 | int num_registers; |
| 1550 | }; |
| 1551 | |
| 1552 | static CompilationResult Compile(Isolate* isolate, Zone* zone, |
Ben Murdoch | 097c5b2 | 2016-05-18 11:27:45 +0100 | [diff] [blame] | 1553 | RegExpCompileData* input, |
| 1554 | JSRegExp::Flags flags, |
Ben Murdoch | 4a90d5f | 2016-03-22 12:00:34 +0000 | [diff] [blame] | 1555 | Handle<String> pattern, |
| 1556 | Handle<String> sample_subject, |
| 1557 | bool is_one_byte); |
| 1558 | |
| 1559 | static bool TooMuchRegExpCode(Handle<String> pattern); |
| 1560 | |
| 1561 | static void DotPrint(const char* label, RegExpNode* node, bool ignore_case); |
| 1562 | }; |
| 1563 | |
| 1564 | |
| 1565 | class RegExpResultsCache : public AllStatic { |
| 1566 | public: |
| 1567 | enum ResultsCacheType { REGEXP_MULTIPLE_INDICES, STRING_SPLIT_SUBSTRINGS }; |
| 1568 | |
| 1569 | // Attempt to retrieve a cached result. On failure, 0 is returned as a Smi. |
| 1570 | // On success, the returned result is guaranteed to be a COW-array. |
| 1571 | static Object* Lookup(Heap* heap, String* key_string, Object* key_pattern, |
| 1572 | FixedArray** last_match_out, ResultsCacheType type); |
| 1573 | // Attempt to add value_array to the cache specified by type. On success, |
| 1574 | // value_array is turned into a COW-array. |
| 1575 | static void Enter(Isolate* isolate, Handle<String> key_string, |
| 1576 | Handle<Object> key_pattern, Handle<FixedArray> value_array, |
| 1577 | Handle<FixedArray> last_match_cache, ResultsCacheType type); |
| 1578 | static void Clear(FixedArray* cache); |
| 1579 | static const int kRegExpResultsCacheSize = 0x100; |
| 1580 | |
| 1581 | private: |
| 1582 | static const int kArrayEntriesPerCacheEntry = 4; |
| 1583 | static const int kStringOffset = 0; |
| 1584 | static const int kPatternOffset = 1; |
| 1585 | static const int kArrayOffset = 2; |
| 1586 | static const int kLastMatchOffset = 3; |
| 1587 | }; |
| 1588 | |
| 1589 | } // namespace internal |
| 1590 | } // namespace v8 |
| 1591 | |
| 1592 | #endif // V8_REGEXP_JSREGEXP_H_ |