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| 1 // Copyright 2011 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 // Features shared by parsing and pre-parsing scanners. | |
| 6 | |
| 7 #include "src/scanner.h" | |
| 8 | |
| 9 #include <stdint.h> | |
| 10 | |
| 11 #include <cmath> | |
| 12 | |
| 13 #include "src/ast-value-factory.h" | |
| 14 #include "src/char-predicates-inl.h" | |
| 15 #include "src/conversions-inl.h" | |
| 16 #include "src/list-inl.h" | |
| 17 #include "src/parser.h" | |
| 18 | |
| 19 namespace v8 { | |
| 20 namespace internal { | |
| 21 | |
| 22 | |
| 23 Handle<String> LiteralBuffer::Internalize(Isolate* isolate) const { | |
| 24 if (is_one_byte()) { | |
| 25 return isolate->factory()->InternalizeOneByteString(one_byte_literal()); | |
| 26 } | |
| 27 return isolate->factory()->InternalizeTwoByteString(two_byte_literal()); | |
| 28 } | |
| 29 | |
| 30 | |
| 31 // Default implementation for streams that do not support bookmarks. | |
| 32 bool Utf16CharacterStream::SetBookmark() { return false; } | |
| 33 void Utf16CharacterStream::ResetToBookmark() { UNREACHABLE(); } | |
| 34 | |
| 35 | |
| 36 // ---------------------------------------------------------------------------- | |
| 37 // Scanner | |
| 38 | |
| 39 Scanner::Scanner(UnicodeCache* unicode_cache) | |
| 40 : unicode_cache_(unicode_cache), | |
| 41 bookmark_c0_(kNoBookmark), | |
| 42 octal_pos_(Location::invalid()) { | |
| 43 bookmark_current_.literal_chars = &bookmark_current_literal_; | |
| 44 bookmark_current_.raw_literal_chars = &bookmark_current_raw_literal_; | |
| 45 bookmark_next_.literal_chars = &bookmark_next_literal_; | |
| 46 bookmark_next_.raw_literal_chars = &bookmark_next_raw_literal_; | |
| 47 } | |
| 48 | |
| 49 | |
| 50 void Scanner::Initialize(Utf16CharacterStream* source) { | |
| 51 source_ = source; | |
| 52 // Need to capture identifiers in order to recognize "get" and "set" | |
| 53 // in object literals. | |
| 54 Init(); | |
| 55 // Skip initial whitespace allowing HTML comment ends just like | |
| 56 // after a newline and scan first token. | |
| 57 has_line_terminator_before_next_ = true; | |
| 58 SkipWhiteSpace(); | |
| 59 Scan(); | |
| 60 } | |
| 61 | |
| 62 | |
| 63 template <bool capture_raw> | |
| 64 uc32 Scanner::ScanHexNumber(int expected_length) { | |
| 65 DCHECK(expected_length <= 4); // prevent overflow | |
| 66 | |
| 67 uc32 x = 0; | |
| 68 for (int i = 0; i < expected_length; i++) { | |
| 69 int d = HexValue(c0_); | |
| 70 if (d < 0) { | |
| 71 return -1; | |
| 72 } | |
| 73 x = x * 16 + d; | |
| 74 Advance<capture_raw>(); | |
| 75 } | |
| 76 | |
| 77 return x; | |
| 78 } | |
| 79 | |
| 80 | |
| 81 template <bool capture_raw> | |
| 82 uc32 Scanner::ScanUnlimitedLengthHexNumber(int max_value) { | |
| 83 uc32 x = 0; | |
| 84 int d = HexValue(c0_); | |
| 85 if (d < 0) { | |
| 86 return -1; | |
| 87 } | |
| 88 while (d >= 0) { | |
| 89 x = x * 16 + d; | |
| 90 if (x > max_value) return -1; | |
| 91 Advance<capture_raw>(); | |
| 92 d = HexValue(c0_); | |
| 93 } | |
| 94 return x; | |
| 95 } | |
| 96 | |
| 97 | |
| 98 // Ensure that tokens can be stored in a byte. | |
| 99 STATIC_ASSERT(Token::NUM_TOKENS <= 0x100); | |
| 100 | |
| 101 // Table of one-character tokens, by character (0x00..0x7f only). | |
| 102 static const byte one_char_tokens[] = { | |
| 103 Token::ILLEGAL, | |
| 104 Token::ILLEGAL, | |
| 105 Token::ILLEGAL, | |
| 106 Token::ILLEGAL, | |
| 107 Token::ILLEGAL, | |
| 108 Token::ILLEGAL, | |
| 109 Token::ILLEGAL, | |
| 110 Token::ILLEGAL, | |
| 111 Token::ILLEGAL, | |
| 112 Token::ILLEGAL, | |
| 113 Token::ILLEGAL, | |
| 114 Token::ILLEGAL, | |
| 115 Token::ILLEGAL, | |
| 116 Token::ILLEGAL, | |
| 117 Token::ILLEGAL, | |
| 118 Token::ILLEGAL, | |
| 119 Token::ILLEGAL, | |
| 120 Token::ILLEGAL, | |
| 121 Token::ILLEGAL, | |
| 122 Token::ILLEGAL, | |
| 123 Token::ILLEGAL, | |
| 124 Token::ILLEGAL, | |
| 125 Token::ILLEGAL, | |
| 126 Token::ILLEGAL, | |
| 127 Token::ILLEGAL, | |
| 128 Token::ILLEGAL, | |
| 129 Token::ILLEGAL, | |
| 130 Token::ILLEGAL, | |
| 131 Token::ILLEGAL, | |
| 132 Token::ILLEGAL, | |
| 133 Token::ILLEGAL, | |
| 134 Token::ILLEGAL, | |
| 135 Token::ILLEGAL, | |
| 136 Token::ILLEGAL, | |
| 137 Token::ILLEGAL, | |
| 138 Token::ILLEGAL, | |
| 139 Token::ILLEGAL, | |
| 140 Token::ILLEGAL, | |
| 141 Token::ILLEGAL, | |
| 142 Token::ILLEGAL, | |
| 143 Token::LPAREN, // 0x28 | |
| 144 Token::RPAREN, // 0x29 | |
| 145 Token::ILLEGAL, | |
| 146 Token::ILLEGAL, | |
| 147 Token::COMMA, // 0x2c | |
| 148 Token::ILLEGAL, | |
| 149 Token::ILLEGAL, | |
| 150 Token::ILLEGAL, | |
| 151 Token::ILLEGAL, | |
| 152 Token::ILLEGAL, | |
| 153 Token::ILLEGAL, | |
| 154 Token::ILLEGAL, | |
| 155 Token::ILLEGAL, | |
| 156 Token::ILLEGAL, | |
| 157 Token::ILLEGAL, | |
| 158 Token::ILLEGAL, | |
| 159 Token::ILLEGAL, | |
| 160 Token::ILLEGAL, | |
| 161 Token::COLON, // 0x3a | |
| 162 Token::SEMICOLON, // 0x3b | |
| 163 Token::ILLEGAL, | |
| 164 Token::ILLEGAL, | |
| 165 Token::ILLEGAL, | |
| 166 Token::CONDITIONAL, // 0x3f | |
| 167 Token::ILLEGAL, | |
| 168 Token::ILLEGAL, | |
| 169 Token::ILLEGAL, | |
| 170 Token::ILLEGAL, | |
| 171 Token::ILLEGAL, | |
| 172 Token::ILLEGAL, | |
| 173 Token::ILLEGAL, | |
| 174 Token::ILLEGAL, | |
| 175 Token::ILLEGAL, | |
| 176 Token::ILLEGAL, | |
| 177 Token::ILLEGAL, | |
| 178 Token::ILLEGAL, | |
| 179 Token::ILLEGAL, | |
| 180 Token::ILLEGAL, | |
| 181 Token::ILLEGAL, | |
| 182 Token::ILLEGAL, | |
| 183 Token::ILLEGAL, | |
| 184 Token::ILLEGAL, | |
| 185 Token::ILLEGAL, | |
| 186 Token::ILLEGAL, | |
| 187 Token::ILLEGAL, | |
| 188 Token::ILLEGAL, | |
| 189 Token::ILLEGAL, | |
| 190 Token::ILLEGAL, | |
| 191 Token::ILLEGAL, | |
| 192 Token::ILLEGAL, | |
| 193 Token::ILLEGAL, | |
| 194 Token::LBRACK, // 0x5b | |
| 195 Token::ILLEGAL, | |
| 196 Token::RBRACK, // 0x5d | |
| 197 Token::ILLEGAL, | |
| 198 Token::ILLEGAL, | |
| 199 Token::ILLEGAL, | |
| 200 Token::ILLEGAL, | |
| 201 Token::ILLEGAL, | |
| 202 Token::ILLEGAL, | |
| 203 Token::ILLEGAL, | |
| 204 Token::ILLEGAL, | |
| 205 Token::ILLEGAL, | |
| 206 Token::ILLEGAL, | |
| 207 Token::ILLEGAL, | |
| 208 Token::ILLEGAL, | |
| 209 Token::ILLEGAL, | |
| 210 Token::ILLEGAL, | |
| 211 Token::ILLEGAL, | |
| 212 Token::ILLEGAL, | |
| 213 Token::ILLEGAL, | |
| 214 Token::ILLEGAL, | |
| 215 Token::ILLEGAL, | |
| 216 Token::ILLEGAL, | |
| 217 Token::ILLEGAL, | |
| 218 Token::ILLEGAL, | |
| 219 Token::ILLEGAL, | |
| 220 Token::ILLEGAL, | |
| 221 Token::ILLEGAL, | |
| 222 Token::ILLEGAL, | |
| 223 Token::ILLEGAL, | |
| 224 Token::ILLEGAL, | |
| 225 Token::ILLEGAL, | |
| 226 Token::LBRACE, // 0x7b | |
| 227 Token::ILLEGAL, | |
| 228 Token::RBRACE, // 0x7d | |
| 229 Token::BIT_NOT, // 0x7e | |
| 230 Token::ILLEGAL | |
| 231 }; | |
| 232 | |
| 233 | |
| 234 Token::Value Scanner::Next() { | |
| 235 if (next_.token == Token::EOS) { | |
| 236 next_.location.beg_pos = current_.location.beg_pos; | |
| 237 next_.location.end_pos = current_.location.end_pos; | |
| 238 } | |
| 239 current_ = next_; | |
| 240 if (V8_UNLIKELY(next_next_.token != Token::UNINITIALIZED)) { | |
| 241 next_ = next_next_; | |
| 242 next_next_.token = Token::UNINITIALIZED; | |
| 243 return current_.token; | |
| 244 } | |
| 245 has_line_terminator_before_next_ = false; | |
| 246 has_multiline_comment_before_next_ = false; | |
| 247 if (static_cast<unsigned>(c0_) <= 0x7f) { | |
| 248 Token::Value token = static_cast<Token::Value>(one_char_tokens[c0_]); | |
| 249 if (token != Token::ILLEGAL) { | |
| 250 int pos = source_pos(); | |
| 251 next_.token = token; | |
| 252 next_.location.beg_pos = pos; | |
| 253 next_.location.end_pos = pos + 1; | |
| 254 Advance(); | |
| 255 return current_.token; | |
| 256 } | |
| 257 } | |
| 258 Scan(); | |
| 259 return current_.token; | |
| 260 } | |
| 261 | |
| 262 | |
| 263 Token::Value Scanner::PeekAhead() { | |
| 264 if (next_next_.token != Token::UNINITIALIZED) { | |
| 265 return next_next_.token; | |
| 266 } | |
| 267 TokenDesc prev = current_; | |
| 268 Next(); | |
| 269 Token::Value ret = next_.token; | |
| 270 next_next_ = next_; | |
| 271 next_ = current_; | |
| 272 current_ = prev; | |
| 273 return ret; | |
| 274 } | |
| 275 | |
| 276 | |
| 277 // TODO(yangguo): check whether this is actually necessary. | |
| 278 static inline bool IsLittleEndianByteOrderMark(uc32 c) { | |
| 279 // The Unicode value U+FFFE is guaranteed never to be assigned as a | |
| 280 // Unicode character; this implies that in a Unicode context the | |
| 281 // 0xFF, 0xFE byte pattern can only be interpreted as the U+FEFF | |
| 282 // character expressed in little-endian byte order (since it could | |
| 283 // not be a U+FFFE character expressed in big-endian byte | |
| 284 // order). Nevertheless, we check for it to be compatible with | |
| 285 // Spidermonkey. | |
| 286 return c == 0xFFFE; | |
| 287 } | |
| 288 | |
| 289 | |
| 290 bool Scanner::SkipWhiteSpace() { | |
| 291 int start_position = source_pos(); | |
| 292 | |
| 293 while (true) { | |
| 294 while (true) { | |
| 295 // The unicode cache accepts unsigned inputs. | |
| 296 if (c0_ < 0) break; | |
| 297 // Advance as long as character is a WhiteSpace or LineTerminator. | |
| 298 // Remember if the latter is the case. | |
| 299 if (unicode_cache_->IsLineTerminator(c0_)) { | |
| 300 has_line_terminator_before_next_ = true; | |
| 301 } else if (!unicode_cache_->IsWhiteSpace(c0_) && | |
| 302 !IsLittleEndianByteOrderMark(c0_)) { | |
| 303 break; | |
| 304 } | |
| 305 Advance(); | |
| 306 } | |
| 307 | |
| 308 // If there is an HTML comment end '-->' at the beginning of a | |
| 309 // line (with only whitespace in front of it), we treat the rest | |
| 310 // of the line as a comment. This is in line with the way | |
| 311 // SpiderMonkey handles it. | |
| 312 if (c0_ == '-' && has_line_terminator_before_next_) { | |
| 313 Advance(); | |
| 314 if (c0_ == '-') { | |
| 315 Advance(); | |
| 316 if (c0_ == '>') { | |
| 317 // Treat the rest of the line as a comment. | |
| 318 SkipSingleLineComment(); | |
| 319 // Continue skipping white space after the comment. | |
| 320 continue; | |
| 321 } | |
| 322 PushBack('-'); // undo Advance() | |
| 323 } | |
| 324 PushBack('-'); // undo Advance() | |
| 325 } | |
| 326 // Return whether or not we skipped any characters. | |
| 327 return source_pos() != start_position; | |
| 328 } | |
| 329 } | |
| 330 | |
| 331 | |
| 332 Token::Value Scanner::SkipSingleLineComment() { | |
| 333 Advance(); | |
| 334 | |
| 335 // The line terminator at the end of the line is not considered | |
| 336 // to be part of the single-line comment; it is recognized | |
| 337 // separately by the lexical grammar and becomes part of the | |
| 338 // stream of input elements for the syntactic grammar (see | |
| 339 // ECMA-262, section 7.4). | |
| 340 while (c0_ >= 0 && !unicode_cache_->IsLineTerminator(c0_)) { | |
| 341 Advance(); | |
| 342 } | |
| 343 | |
| 344 return Token::WHITESPACE; | |
| 345 } | |
| 346 | |
| 347 | |
| 348 Token::Value Scanner::SkipSourceURLComment() { | |
| 349 TryToParseSourceURLComment(); | |
| 350 while (c0_ >= 0 && !unicode_cache_->IsLineTerminator(c0_)) { | |
| 351 Advance(); | |
| 352 } | |
| 353 | |
| 354 return Token::WHITESPACE; | |
| 355 } | |
| 356 | |
| 357 | |
| 358 void Scanner::TryToParseSourceURLComment() { | |
| 359 // Magic comments are of the form: //[#@]\s<name>=\s*<value>\s*.* and this | |
| 360 // function will just return if it cannot parse a magic comment. | |
| 361 if (c0_ < 0 || !unicode_cache_->IsWhiteSpace(c0_)) return; | |
| 362 Advance(); | |
| 363 LiteralBuffer name; | |
| 364 while (c0_ >= 0 && !unicode_cache_->IsWhiteSpaceOrLineTerminator(c0_) && | |
| 365 c0_ != '=') { | |
| 366 name.AddChar(c0_); | |
| 367 Advance(); | |
| 368 } | |
| 369 if (!name.is_one_byte()) return; | |
| 370 Vector<const uint8_t> name_literal = name.one_byte_literal(); | |
| 371 LiteralBuffer* value; | |
| 372 if (name_literal == STATIC_CHAR_VECTOR("sourceURL")) { | |
| 373 value = &source_url_; | |
| 374 } else if (name_literal == STATIC_CHAR_VECTOR("sourceMappingURL")) { | |
| 375 value = &source_mapping_url_; | |
| 376 } else { | |
| 377 return; | |
| 378 } | |
| 379 if (c0_ != '=') | |
| 380 return; | |
| 381 Advance(); | |
| 382 value->Reset(); | |
| 383 while (c0_ >= 0 && unicode_cache_->IsWhiteSpace(c0_)) { | |
| 384 Advance(); | |
| 385 } | |
| 386 while (c0_ >= 0 && !unicode_cache_->IsLineTerminator(c0_)) { | |
| 387 // Disallowed characters. | |
| 388 if (c0_ == '"' || c0_ == '\'') { | |
| 389 value->Reset(); | |
| 390 return; | |
| 391 } | |
| 392 if (unicode_cache_->IsWhiteSpace(c0_)) { | |
| 393 break; | |
| 394 } | |
| 395 value->AddChar(c0_); | |
| 396 Advance(); | |
| 397 } | |
| 398 // Allow whitespace at the end. | |
| 399 while (c0_ >= 0 && !unicode_cache_->IsLineTerminator(c0_)) { | |
| 400 if (!unicode_cache_->IsWhiteSpace(c0_)) { | |
| 401 value->Reset(); | |
| 402 break; | |
| 403 } | |
| 404 Advance(); | |
| 405 } | |
| 406 } | |
| 407 | |
| 408 | |
| 409 Token::Value Scanner::SkipMultiLineComment() { | |
| 410 DCHECK(c0_ == '*'); | |
| 411 Advance(); | |
| 412 | |
| 413 while (c0_ >= 0) { | |
| 414 uc32 ch = c0_; | |
| 415 Advance(); | |
| 416 if (c0_ >= 0 && unicode_cache_->IsLineTerminator(ch)) { | |
| 417 // Following ECMA-262, section 7.4, a comment containing | |
| 418 // a newline will make the comment count as a line-terminator. | |
| 419 has_multiline_comment_before_next_ = true; | |
| 420 } | |
| 421 // If we have reached the end of the multi-line comment, we | |
| 422 // consume the '/' and insert a whitespace. This way all | |
| 423 // multi-line comments are treated as whitespace. | |
| 424 if (ch == '*' && c0_ == '/') { | |
| 425 c0_ = ' '; | |
| 426 return Token::WHITESPACE; | |
| 427 } | |
| 428 } | |
| 429 | |
| 430 // Unterminated multi-line comment. | |
| 431 return Token::ILLEGAL; | |
| 432 } | |
| 433 | |
| 434 | |
| 435 Token::Value Scanner::ScanHtmlComment() { | |
| 436 // Check for <!-- comments. | |
| 437 DCHECK(c0_ == '!'); | |
| 438 Advance(); | |
| 439 if (c0_ == '-') { | |
| 440 Advance(); | |
| 441 if (c0_ == '-') return SkipSingleLineComment(); | |
| 442 PushBack('-'); // undo Advance() | |
| 443 } | |
| 444 PushBack('!'); // undo Advance() | |
| 445 DCHECK(c0_ == '!'); | |
| 446 return Token::LT; | |
| 447 } | |
| 448 | |
| 449 | |
| 450 void Scanner::Scan() { | |
| 451 next_.literal_chars = NULL; | |
| 452 next_.raw_literal_chars = NULL; | |
| 453 Token::Value token; | |
| 454 do { | |
| 455 // Remember the position of the next token | |
| 456 next_.location.beg_pos = source_pos(); | |
| 457 | |
| 458 switch (c0_) { | |
| 459 case ' ': | |
| 460 case '\t': | |
| 461 Advance(); | |
| 462 token = Token::WHITESPACE; | |
| 463 break; | |
| 464 | |
| 465 case '\n': | |
| 466 Advance(); | |
| 467 has_line_terminator_before_next_ = true; | |
| 468 token = Token::WHITESPACE; | |
| 469 break; | |
| 470 | |
| 471 case '"': case '\'': | |
| 472 token = ScanString(); | |
| 473 break; | |
| 474 | |
| 475 case '<': | |
| 476 // < <= << <<= <!-- | |
| 477 Advance(); | |
| 478 if (c0_ == '=') { | |
| 479 token = Select(Token::LTE); | |
| 480 } else if (c0_ == '<') { | |
| 481 token = Select('=', Token::ASSIGN_SHL, Token::SHL); | |
| 482 } else if (c0_ == '!') { | |
| 483 token = ScanHtmlComment(); | |
| 484 } else { | |
| 485 token = Token::LT; | |
| 486 } | |
| 487 break; | |
| 488 | |
| 489 case '>': | |
| 490 // > >= >> >>= >>> >>>= | |
| 491 Advance(); | |
| 492 if (c0_ == '=') { | |
| 493 token = Select(Token::GTE); | |
| 494 } else if (c0_ == '>') { | |
| 495 // >> >>= >>> >>>= | |
| 496 Advance(); | |
| 497 if (c0_ == '=') { | |
| 498 token = Select(Token::ASSIGN_SAR); | |
| 499 } else if (c0_ == '>') { | |
| 500 token = Select('=', Token::ASSIGN_SHR, Token::SHR); | |
| 501 } else { | |
| 502 token = Token::SAR; | |
| 503 } | |
| 504 } else { | |
| 505 token = Token::GT; | |
| 506 } | |
| 507 break; | |
| 508 | |
| 509 case '=': | |
| 510 // = == === => | |
| 511 Advance(); | |
| 512 if (c0_ == '=') { | |
| 513 token = Select('=', Token::EQ_STRICT, Token::EQ); | |
| 514 } else if (c0_ == '>') { | |
| 515 token = Select(Token::ARROW); | |
| 516 } else { | |
| 517 token = Token::ASSIGN; | |
| 518 } | |
| 519 break; | |
| 520 | |
| 521 case '!': | |
| 522 // ! != !== | |
| 523 Advance(); | |
| 524 if (c0_ == '=') { | |
| 525 token = Select('=', Token::NE_STRICT, Token::NE); | |
| 526 } else { | |
| 527 token = Token::NOT; | |
| 528 } | |
| 529 break; | |
| 530 | |
| 531 case '+': | |
| 532 // + ++ += | |
| 533 Advance(); | |
| 534 if (c0_ == '+') { | |
| 535 token = Select(Token::INC); | |
| 536 } else if (c0_ == '=') { | |
| 537 token = Select(Token::ASSIGN_ADD); | |
| 538 } else { | |
| 539 token = Token::ADD; | |
| 540 } | |
| 541 break; | |
| 542 | |
| 543 case '-': | |
| 544 // - -- --> -= | |
| 545 Advance(); | |
| 546 if (c0_ == '-') { | |
| 547 Advance(); | |
| 548 if (c0_ == '>' && has_line_terminator_before_next_) { | |
| 549 // For compatibility with SpiderMonkey, we skip lines that | |
| 550 // start with an HTML comment end '-->'. | |
| 551 token = SkipSingleLineComment(); | |
| 552 } else { | |
| 553 token = Token::DEC; | |
| 554 } | |
| 555 } else if (c0_ == '=') { | |
| 556 token = Select(Token::ASSIGN_SUB); | |
| 557 } else { | |
| 558 token = Token::SUB; | |
| 559 } | |
| 560 break; | |
| 561 | |
| 562 case '*': | |
| 563 // * *= | |
| 564 token = Select('=', Token::ASSIGN_MUL, Token::MUL); | |
| 565 break; | |
| 566 | |
| 567 case '%': | |
| 568 // % %= | |
| 569 token = Select('=', Token::ASSIGN_MOD, Token::MOD); | |
| 570 break; | |
| 571 | |
| 572 case '/': | |
| 573 // / // /* /= | |
| 574 Advance(); | |
| 575 if (c0_ == '/') { | |
| 576 Advance(); | |
| 577 if (c0_ == '@' || c0_ == '#') { | |
| 578 Advance(); | |
| 579 token = SkipSourceURLComment(); | |
| 580 } else { | |
| 581 PushBack(c0_); | |
| 582 token = SkipSingleLineComment(); | |
| 583 } | |
| 584 } else if (c0_ == '*') { | |
| 585 token = SkipMultiLineComment(); | |
| 586 } else if (c0_ == '=') { | |
| 587 token = Select(Token::ASSIGN_DIV); | |
| 588 } else { | |
| 589 token = Token::DIV; | |
| 590 } | |
| 591 break; | |
| 592 | |
| 593 case '&': | |
| 594 // & && &= | |
| 595 Advance(); | |
| 596 if (c0_ == '&') { | |
| 597 token = Select(Token::AND); | |
| 598 } else if (c0_ == '=') { | |
| 599 token = Select(Token::ASSIGN_BIT_AND); | |
| 600 } else { | |
| 601 token = Token::BIT_AND; | |
| 602 } | |
| 603 break; | |
| 604 | |
| 605 case '|': | |
| 606 // | || |= | |
| 607 Advance(); | |
| 608 if (c0_ == '|') { | |
| 609 token = Select(Token::OR); | |
| 610 } else if (c0_ == '=') { | |
| 611 token = Select(Token::ASSIGN_BIT_OR); | |
| 612 } else { | |
| 613 token = Token::BIT_OR; | |
| 614 } | |
| 615 break; | |
| 616 | |
| 617 case '^': | |
| 618 // ^ ^= | |
| 619 token = Select('=', Token::ASSIGN_BIT_XOR, Token::BIT_XOR); | |
| 620 break; | |
| 621 | |
| 622 case '.': | |
| 623 // . Number | |
| 624 Advance(); | |
| 625 if (IsDecimalDigit(c0_)) { | |
| 626 token = ScanNumber(true); | |
| 627 } else { | |
| 628 token = Token::PERIOD; | |
| 629 if (c0_ == '.') { | |
| 630 Advance(); | |
| 631 if (c0_ == '.') { | |
| 632 Advance(); | |
| 633 token = Token::ELLIPSIS; | |
| 634 } else { | |
| 635 PushBack('.'); | |
| 636 } | |
| 637 } | |
| 638 } | |
| 639 break; | |
| 640 | |
| 641 case ':': | |
| 642 token = Select(Token::COLON); | |
| 643 break; | |
| 644 | |
| 645 case ';': | |
| 646 token = Select(Token::SEMICOLON); | |
| 647 break; | |
| 648 | |
| 649 case ',': | |
| 650 token = Select(Token::COMMA); | |
| 651 break; | |
| 652 | |
| 653 case '(': | |
| 654 token = Select(Token::LPAREN); | |
| 655 break; | |
| 656 | |
| 657 case ')': | |
| 658 token = Select(Token::RPAREN); | |
| 659 break; | |
| 660 | |
| 661 case '[': | |
| 662 token = Select(Token::LBRACK); | |
| 663 break; | |
| 664 | |
| 665 case ']': | |
| 666 token = Select(Token::RBRACK); | |
| 667 break; | |
| 668 | |
| 669 case '{': | |
| 670 token = Select(Token::LBRACE); | |
| 671 break; | |
| 672 | |
| 673 case '}': | |
| 674 token = Select(Token::RBRACE); | |
| 675 break; | |
| 676 | |
| 677 case '?': | |
| 678 token = Select(Token::CONDITIONAL); | |
| 679 break; | |
| 680 | |
| 681 case '~': | |
| 682 token = Select(Token::BIT_NOT); | |
| 683 break; | |
| 684 | |
| 685 case '`': | |
| 686 token = ScanTemplateStart(); | |
| 687 break; | |
| 688 | |
| 689 default: | |
| 690 if (c0_ < 0) { | |
| 691 token = Token::EOS; | |
| 692 } else if (unicode_cache_->IsIdentifierStart(c0_)) { | |
| 693 token = ScanIdentifierOrKeyword(); | |
| 694 } else if (IsDecimalDigit(c0_)) { | |
| 695 token = ScanNumber(false); | |
| 696 } else if (SkipWhiteSpace()) { | |
| 697 token = Token::WHITESPACE; | |
| 698 } else { | |
| 699 token = Select(Token::ILLEGAL); | |
| 700 } | |
| 701 break; | |
| 702 } | |
| 703 | |
| 704 // Continue scanning for tokens as long as we're just skipping | |
| 705 // whitespace. | |
| 706 } while (token == Token::WHITESPACE); | |
| 707 | |
| 708 next_.location.end_pos = source_pos(); | |
| 709 next_.token = token; | |
| 710 } | |
| 711 | |
| 712 | |
| 713 void Scanner::SeekForward(int pos) { | |
| 714 // After this call, we will have the token at the given position as | |
| 715 // the "next" token. The "current" token will be invalid. | |
| 716 if (pos == next_.location.beg_pos) return; | |
| 717 int current_pos = source_pos(); | |
| 718 DCHECK_EQ(next_.location.end_pos, current_pos); | |
| 719 // Positions inside the lookahead token aren't supported. | |
| 720 DCHECK(pos >= current_pos); | |
| 721 if (pos != current_pos) { | |
| 722 source_->SeekForward(pos - source_->pos()); | |
| 723 Advance(); | |
| 724 // This function is only called to seek to the location | |
| 725 // of the end of a function (at the "}" token). It doesn't matter | |
| 726 // whether there was a line terminator in the part we skip. | |
| 727 has_line_terminator_before_next_ = false; | |
| 728 has_multiline_comment_before_next_ = false; | |
| 729 } | |
| 730 Scan(); | |
| 731 } | |
| 732 | |
| 733 | |
| 734 template <bool capture_raw, bool in_template_literal> | |
| 735 bool Scanner::ScanEscape() { | |
| 736 uc32 c = c0_; | |
| 737 Advance<capture_raw>(); | |
| 738 | |
| 739 // Skip escaped newlines. | |
| 740 if (!in_template_literal && c0_ >= 0 && unicode_cache_->IsLineTerminator(c)) { | |
| 741 // Allow CR+LF newlines in multiline string literals. | |
| 742 if (IsCarriageReturn(c) && IsLineFeed(c0_)) Advance<capture_raw>(); | |
| 743 // Allow LF+CR newlines in multiline string literals. | |
| 744 if (IsLineFeed(c) && IsCarriageReturn(c0_)) Advance<capture_raw>(); | |
| 745 return true; | |
| 746 } | |
| 747 | |
| 748 switch (c) { | |
| 749 case '\'': // fall through | |
| 750 case '"' : // fall through | |
| 751 case '\\': break; | |
| 752 case 'b' : c = '\b'; break; | |
| 753 case 'f' : c = '\f'; break; | |
| 754 case 'n' : c = '\n'; break; | |
| 755 case 'r' : c = '\r'; break; | |
| 756 case 't' : c = '\t'; break; | |
| 757 case 'u' : { | |
| 758 c = ScanUnicodeEscape<capture_raw>(); | |
| 759 if (c < 0) return false; | |
| 760 break; | |
| 761 } | |
| 762 case 'v': | |
| 763 c = '\v'; | |
| 764 break; | |
| 765 case 'x': { | |
| 766 c = ScanHexNumber<capture_raw>(2); | |
| 767 if (c < 0) return false; | |
| 768 break; | |
| 769 } | |
| 770 case '0': // Fall through. | |
| 771 case '1': // fall through | |
| 772 case '2': // fall through | |
| 773 case '3': // fall through | |
| 774 case '4': // fall through | |
| 775 case '5': // fall through | |
| 776 case '6': // fall through | |
| 777 case '7': | |
| 778 c = ScanOctalEscape<capture_raw>(c, 2); | |
| 779 break; | |
| 780 } | |
| 781 | |
| 782 // According to ECMA-262, section 7.8.4, characters not covered by the | |
| 783 // above cases should be illegal, but they are commonly handled as | |
| 784 // non-escaped characters by JS VMs. | |
| 785 AddLiteralChar(c); | |
| 786 return true; | |
| 787 } | |
| 788 | |
| 789 | |
| 790 // Octal escapes of the forms '\0xx' and '\xxx' are not a part of | |
| 791 // ECMA-262. Other JS VMs support them. | |
| 792 template <bool capture_raw> | |
| 793 uc32 Scanner::ScanOctalEscape(uc32 c, int length) { | |
| 794 uc32 x = c - '0'; | |
| 795 int i = 0; | |
| 796 for (; i < length; i++) { | |
| 797 int d = c0_ - '0'; | |
| 798 if (d < 0 || d > 7) break; | |
| 799 int nx = x * 8 + d; | |
| 800 if (nx >= 256) break; | |
| 801 x = nx; | |
| 802 Advance<capture_raw>(); | |
| 803 } | |
| 804 // Anything except '\0' is an octal escape sequence, illegal in strict mode. | |
| 805 // Remember the position of octal escape sequences so that an error | |
| 806 // can be reported later (in strict mode). | |
| 807 // We don't report the error immediately, because the octal escape can | |
| 808 // occur before the "use strict" directive. | |
| 809 if (c != '0' || i > 0) { | |
| 810 octal_pos_ = Location(source_pos() - i - 1, source_pos() - 1); | |
| 811 } | |
| 812 return x; | |
| 813 } | |
| 814 | |
| 815 | |
| 816 const int kMaxAscii = 127; | |
| 817 | |
| 818 | |
| 819 Token::Value Scanner::ScanString() { | |
| 820 uc32 quote = c0_; | |
| 821 Advance<false, false>(); // consume quote | |
| 822 | |
| 823 LiteralScope literal(this); | |
| 824 while (true) { | |
| 825 if (c0_ > kMaxAscii) { | |
| 826 HandleLeadSurrogate(); | |
| 827 break; | |
| 828 } | |
| 829 if (c0_ < 0 || c0_ == '\n' || c0_ == '\r') return Token::ILLEGAL; | |
| 830 if (c0_ == quote) { | |
| 831 literal.Complete(); | |
| 832 Advance<false, false>(); | |
| 833 return Token::STRING; | |
| 834 } | |
| 835 uc32 c = c0_; | |
| 836 if (c == '\\') break; | |
| 837 Advance<false, false>(); | |
| 838 AddLiteralChar(c); | |
| 839 } | |
| 840 | |
| 841 while (c0_ != quote && c0_ >= 0 | |
| 842 && !unicode_cache_->IsLineTerminator(c0_)) { | |
| 843 uc32 c = c0_; | |
| 844 Advance(); | |
| 845 if (c == '\\') { | |
| 846 if (c0_ < 0 || !ScanEscape<false, false>()) return Token::ILLEGAL; | |
| 847 } else { | |
| 848 AddLiteralChar(c); | |
| 849 } | |
| 850 } | |
| 851 if (c0_ != quote) return Token::ILLEGAL; | |
| 852 literal.Complete(); | |
| 853 | |
| 854 Advance(); // consume quote | |
| 855 return Token::STRING; | |
| 856 } | |
| 857 | |
| 858 | |
| 859 Token::Value Scanner::ScanTemplateSpan() { | |
| 860 // When scanning a TemplateSpan, we are looking for the following construct: | |
| 861 // TEMPLATE_SPAN :: | |
| 862 // ` LiteralChars* ${ | |
| 863 // | } LiteralChars* ${ | |
| 864 // | |
| 865 // TEMPLATE_TAIL :: | |
| 866 // ` LiteralChars* ` | |
| 867 // | } LiteralChar* ` | |
| 868 // | |
| 869 // A TEMPLATE_SPAN should always be followed by an Expression, while a | |
| 870 // TEMPLATE_TAIL terminates a TemplateLiteral and does not need to be | |
| 871 // followed by an Expression. | |
| 872 | |
| 873 Token::Value result = Token::TEMPLATE_SPAN; | |
| 874 LiteralScope literal(this); | |
| 875 StartRawLiteral(); | |
| 876 const bool capture_raw = true; | |
| 877 const bool in_template_literal = true; | |
| 878 | |
| 879 while (true) { | |
| 880 uc32 c = c0_; | |
| 881 Advance<capture_raw>(); | |
| 882 if (c == '`') { | |
| 883 result = Token::TEMPLATE_TAIL; | |
| 884 ReduceRawLiteralLength(1); | |
| 885 break; | |
| 886 } else if (c == '$' && c0_ == '{') { | |
| 887 Advance<capture_raw>(); // Consume '{' | |
| 888 ReduceRawLiteralLength(2); | |
| 889 break; | |
| 890 } else if (c == '\\') { | |
| 891 if (c0_ > 0 && unicode_cache_->IsLineTerminator(c0_)) { | |
| 892 // The TV of LineContinuation :: \ LineTerminatorSequence is the empty | |
| 893 // code unit sequence. | |
| 894 uc32 lastChar = c0_; | |
| 895 Advance<capture_raw>(); | |
| 896 if (lastChar == '\r') { | |
| 897 ReduceRawLiteralLength(1); // Remove \r | |
| 898 if (c0_ == '\n') { | |
| 899 Advance<capture_raw>(); // Adds \n | |
| 900 } else { | |
| 901 AddRawLiteralChar('\n'); | |
| 902 } | |
| 903 } | |
| 904 } else if (!ScanEscape<capture_raw, in_template_literal>()) { | |
| 905 return Token::ILLEGAL; | |
| 906 } | |
| 907 } else if (c < 0) { | |
| 908 // Unterminated template literal | |
| 909 PushBack(c); | |
| 910 break; | |
| 911 } else { | |
| 912 // The TRV of LineTerminatorSequence :: <CR> is the CV 0x000A. | |
| 913 // The TRV of LineTerminatorSequence :: <CR><LF> is the sequence | |
| 914 // consisting of the CV 0x000A. | |
| 915 if (c == '\r') { | |
| 916 ReduceRawLiteralLength(1); // Remove \r | |
| 917 if (c0_ == '\n') { | |
| 918 Advance<capture_raw>(); // Adds \n | |
| 919 } else { | |
| 920 AddRawLiteralChar('\n'); | |
| 921 } | |
| 922 c = '\n'; | |
| 923 } | |
| 924 AddLiteralChar(c); | |
| 925 } | |
| 926 } | |
| 927 literal.Complete(); | |
| 928 next_.location.end_pos = source_pos(); | |
| 929 next_.token = result; | |
| 930 return result; | |
| 931 } | |
| 932 | |
| 933 | |
| 934 Token::Value Scanner::ScanTemplateStart() { | |
| 935 DCHECK(c0_ == '`'); | |
| 936 next_.location.beg_pos = source_pos(); | |
| 937 Advance(); // Consume ` | |
| 938 return ScanTemplateSpan(); | |
| 939 } | |
| 940 | |
| 941 | |
| 942 Token::Value Scanner::ScanTemplateContinuation() { | |
| 943 DCHECK_EQ(next_.token, Token::RBRACE); | |
| 944 next_.location.beg_pos = source_pos() - 1; // We already consumed } | |
| 945 return ScanTemplateSpan(); | |
| 946 } | |
| 947 | |
| 948 | |
| 949 void Scanner::ScanDecimalDigits() { | |
| 950 while (IsDecimalDigit(c0_)) | |
| 951 AddLiteralCharAdvance(); | |
| 952 } | |
| 953 | |
| 954 | |
| 955 Token::Value Scanner::ScanNumber(bool seen_period) { | |
| 956 DCHECK(IsDecimalDigit(c0_)); // the first digit of the number or the fraction | |
| 957 | |
| 958 enum { DECIMAL, HEX, OCTAL, IMPLICIT_OCTAL, BINARY } kind = DECIMAL; | |
| 959 | |
| 960 LiteralScope literal(this); | |
| 961 bool at_start = !seen_period; | |
| 962 if (seen_period) { | |
| 963 // we have already seen a decimal point of the float | |
| 964 AddLiteralChar('.'); | |
| 965 ScanDecimalDigits(); // we know we have at least one digit | |
| 966 | |
| 967 } else { | |
| 968 // if the first character is '0' we must check for octals and hex | |
| 969 if (c0_ == '0') { | |
| 970 int start_pos = source_pos(); // For reporting octal positions. | |
| 971 AddLiteralCharAdvance(); | |
| 972 | |
| 973 // either 0, 0exxx, 0Exxx, 0.xxx, a hex number, a binary number or | |
| 974 // an octal number. | |
| 975 if (c0_ == 'x' || c0_ == 'X') { | |
| 976 // hex number | |
| 977 kind = HEX; | |
| 978 AddLiteralCharAdvance(); | |
| 979 if (!IsHexDigit(c0_)) { | |
| 980 // we must have at least one hex digit after 'x'/'X' | |
| 981 return Token::ILLEGAL; | |
| 982 } | |
| 983 while (IsHexDigit(c0_)) { | |
| 984 AddLiteralCharAdvance(); | |
| 985 } | |
| 986 } else if (c0_ == 'o' || c0_ == 'O') { | |
| 987 kind = OCTAL; | |
| 988 AddLiteralCharAdvance(); | |
| 989 if (!IsOctalDigit(c0_)) { | |
| 990 // we must have at least one octal digit after 'o'/'O' | |
| 991 return Token::ILLEGAL; | |
| 992 } | |
| 993 while (IsOctalDigit(c0_)) { | |
| 994 AddLiteralCharAdvance(); | |
| 995 } | |
| 996 } else if (c0_ == 'b' || c0_ == 'B') { | |
| 997 kind = BINARY; | |
| 998 AddLiteralCharAdvance(); | |
| 999 if (!IsBinaryDigit(c0_)) { | |
| 1000 // we must have at least one binary digit after 'b'/'B' | |
| 1001 return Token::ILLEGAL; | |
| 1002 } | |
| 1003 while (IsBinaryDigit(c0_)) { | |
| 1004 AddLiteralCharAdvance(); | |
| 1005 } | |
| 1006 } else if ('0' <= c0_ && c0_ <= '7') { | |
| 1007 // (possible) octal number | |
| 1008 kind = IMPLICIT_OCTAL; | |
| 1009 while (true) { | |
| 1010 if (c0_ == '8' || c0_ == '9') { | |
| 1011 at_start = false; | |
| 1012 kind = DECIMAL; | |
| 1013 break; | |
| 1014 } | |
| 1015 if (c0_ < '0' || '7' < c0_) { | |
| 1016 // Octal literal finished. | |
| 1017 octal_pos_ = Location(start_pos, source_pos()); | |
| 1018 break; | |
| 1019 } | |
| 1020 AddLiteralCharAdvance(); | |
| 1021 } | |
| 1022 } | |
| 1023 } | |
| 1024 | |
| 1025 // Parse decimal digits and allow trailing fractional part. | |
| 1026 if (kind == DECIMAL) { | |
| 1027 if (at_start) { | |
| 1028 uint64_t value = 0; | |
| 1029 while (IsDecimalDigit(c0_)) { | |
| 1030 value = 10 * value + (c0_ - '0'); | |
| 1031 | |
| 1032 uc32 first_char = c0_; | |
| 1033 Advance<false, false>(); | |
| 1034 AddLiteralChar(first_char); | |
| 1035 } | |
| 1036 | |
| 1037 if (next_.literal_chars->one_byte_literal().length() <= 10 && | |
| 1038 value <= Smi::kMaxValue && c0_ != '.' && c0_ != 'e' && c0_ != 'E') { | |
| 1039 next_.smi_value_ = static_cast<int>(value); | |
| 1040 literal.Complete(); | |
| 1041 HandleLeadSurrogate(); | |
| 1042 | |
| 1043 return Token::SMI; | |
| 1044 } | |
| 1045 HandleLeadSurrogate(); | |
| 1046 } | |
| 1047 | |
| 1048 ScanDecimalDigits(); // optional | |
| 1049 if (c0_ == '.') { | |
| 1050 AddLiteralCharAdvance(); | |
| 1051 ScanDecimalDigits(); // optional | |
| 1052 } | |
| 1053 } | |
| 1054 } | |
| 1055 | |
| 1056 // scan exponent, if any | |
| 1057 if (c0_ == 'e' || c0_ == 'E') { | |
| 1058 DCHECK(kind != HEX); // 'e'/'E' must be scanned as part of the hex number | |
| 1059 if (kind != DECIMAL) return Token::ILLEGAL; | |
| 1060 // scan exponent | |
| 1061 AddLiteralCharAdvance(); | |
| 1062 if (c0_ == '+' || c0_ == '-') | |
| 1063 AddLiteralCharAdvance(); | |
| 1064 if (!IsDecimalDigit(c0_)) { | |
| 1065 // we must have at least one decimal digit after 'e'/'E' | |
| 1066 return Token::ILLEGAL; | |
| 1067 } | |
| 1068 ScanDecimalDigits(); | |
| 1069 } | |
| 1070 | |
| 1071 // The source character immediately following a numeric literal must | |
| 1072 // not be an identifier start or a decimal digit; see ECMA-262 | |
| 1073 // section 7.8.3, page 17 (note that we read only one decimal digit | |
| 1074 // if the value is 0). | |
| 1075 if (IsDecimalDigit(c0_) || | |
| 1076 (c0_ >= 0 && unicode_cache_->IsIdentifierStart(c0_))) | |
| 1077 return Token::ILLEGAL; | |
| 1078 | |
| 1079 literal.Complete(); | |
| 1080 | |
| 1081 return Token::NUMBER; | |
| 1082 } | |
| 1083 | |
| 1084 | |
| 1085 uc32 Scanner::ScanIdentifierUnicodeEscape() { | |
| 1086 Advance(); | |
| 1087 if (c0_ != 'u') return -1; | |
| 1088 Advance(); | |
| 1089 return ScanUnicodeEscape<false>(); | |
| 1090 } | |
| 1091 | |
| 1092 | |
| 1093 template <bool capture_raw> | |
| 1094 uc32 Scanner::ScanUnicodeEscape() { | |
| 1095 // Accept both \uxxxx and \u{xxxxxx}. In the latter case, the number of | |
| 1096 // hex digits between { } is arbitrary. \ and u have already been read. | |
| 1097 if (c0_ == '{') { | |
| 1098 Advance<capture_raw>(); | |
| 1099 uc32 cp = ScanUnlimitedLengthHexNumber<capture_raw>(0x10ffff); | |
| 1100 if (cp < 0) { | |
| 1101 return -1; | |
| 1102 } | |
| 1103 if (c0_ != '}') { | |
| 1104 return -1; | |
| 1105 } | |
| 1106 Advance<capture_raw>(); | |
| 1107 return cp; | |
| 1108 } | |
| 1109 return ScanHexNumber<capture_raw>(4); | |
| 1110 } | |
| 1111 | |
| 1112 | |
| 1113 // ---------------------------------------------------------------------------- | |
| 1114 // Keyword Matcher | |
| 1115 | |
| 1116 #define KEYWORDS(KEYWORD_GROUP, KEYWORD) \ | |
| 1117 KEYWORD_GROUP('b') \ | |
| 1118 KEYWORD("break", Token::BREAK) \ | |
| 1119 KEYWORD_GROUP('c') \ | |
| 1120 KEYWORD("case", Token::CASE) \ | |
| 1121 KEYWORD("catch", Token::CATCH) \ | |
| 1122 KEYWORD("class", Token::CLASS) \ | |
| 1123 KEYWORD("const", Token::CONST) \ | |
| 1124 KEYWORD("continue", Token::CONTINUE) \ | |
| 1125 KEYWORD_GROUP('d') \ | |
| 1126 KEYWORD("debugger", Token::DEBUGGER) \ | |
| 1127 KEYWORD("default", Token::DEFAULT) \ | |
| 1128 KEYWORD("delete", Token::DELETE) \ | |
| 1129 KEYWORD("do", Token::DO) \ | |
| 1130 KEYWORD_GROUP('e') \ | |
| 1131 KEYWORD("else", Token::ELSE) \ | |
| 1132 KEYWORD("enum", Token::FUTURE_RESERVED_WORD) \ | |
| 1133 KEYWORD("export", Token::EXPORT) \ | |
| 1134 KEYWORD("extends", Token::EXTENDS) \ | |
| 1135 KEYWORD_GROUP('f') \ | |
| 1136 KEYWORD("false", Token::FALSE_LITERAL) \ | |
| 1137 KEYWORD("finally", Token::FINALLY) \ | |
| 1138 KEYWORD("for", Token::FOR) \ | |
| 1139 KEYWORD("function", Token::FUNCTION) \ | |
| 1140 KEYWORD_GROUP('i') \ | |
| 1141 KEYWORD("if", Token::IF) \ | |
| 1142 KEYWORD("implements", Token::FUTURE_STRICT_RESERVED_WORD) \ | |
| 1143 KEYWORD("import", Token::IMPORT) \ | |
| 1144 KEYWORD("in", Token::IN) \ | |
| 1145 KEYWORD("instanceof", Token::INSTANCEOF) \ | |
| 1146 KEYWORD("interface", Token::FUTURE_STRICT_RESERVED_WORD) \ | |
| 1147 KEYWORD_GROUP('l') \ | |
| 1148 KEYWORD("let", Token::LET) \ | |
| 1149 KEYWORD_GROUP('n') \ | |
| 1150 KEYWORD("new", Token::NEW) \ | |
| 1151 KEYWORD("null", Token::NULL_LITERAL) \ | |
| 1152 KEYWORD_GROUP('p') \ | |
| 1153 KEYWORD("package", Token::FUTURE_STRICT_RESERVED_WORD) \ | |
| 1154 KEYWORD("private", Token::FUTURE_STRICT_RESERVED_WORD) \ | |
| 1155 KEYWORD("protected", Token::FUTURE_STRICT_RESERVED_WORD) \ | |
| 1156 KEYWORD("public", Token::FUTURE_STRICT_RESERVED_WORD) \ | |
| 1157 KEYWORD_GROUP('r') \ | |
| 1158 KEYWORD("return", Token::RETURN) \ | |
| 1159 KEYWORD_GROUP('s') \ | |
| 1160 KEYWORD("static", Token::STATIC) \ | |
| 1161 KEYWORD("super", Token::SUPER) \ | |
| 1162 KEYWORD("switch", Token::SWITCH) \ | |
| 1163 KEYWORD_GROUP('t') \ | |
| 1164 KEYWORD("this", Token::THIS) \ | |
| 1165 KEYWORD("throw", Token::THROW) \ | |
| 1166 KEYWORD("true", Token::TRUE_LITERAL) \ | |
| 1167 KEYWORD("try", Token::TRY) \ | |
| 1168 KEYWORD("typeof", Token::TYPEOF) \ | |
| 1169 KEYWORD_GROUP('v') \ | |
| 1170 KEYWORD("var", Token::VAR) \ | |
| 1171 KEYWORD("void", Token::VOID) \ | |
| 1172 KEYWORD_GROUP('w') \ | |
| 1173 KEYWORD("while", Token::WHILE) \ | |
| 1174 KEYWORD("with", Token::WITH) \ | |
| 1175 KEYWORD_GROUP('y') \ | |
| 1176 KEYWORD("yield", Token::YIELD) | |
| 1177 | |
| 1178 | |
| 1179 static Token::Value KeywordOrIdentifierToken(const uint8_t* input, | |
| 1180 int input_length, bool escaped) { | |
| 1181 DCHECK(input_length >= 1); | |
| 1182 const int kMinLength = 2; | |
| 1183 const int kMaxLength = 10; | |
| 1184 if (input_length < kMinLength || input_length > kMaxLength) { | |
| 1185 return Token::IDENTIFIER; | |
| 1186 } | |
| 1187 switch (input[0]) { | |
| 1188 default: | |
| 1189 #define KEYWORD_GROUP_CASE(ch) \ | |
| 1190 break; \ | |
| 1191 case ch: | |
| 1192 #define KEYWORD(keyword, token) \ | |
| 1193 { \ | |
| 1194 /* 'keyword' is a char array, so sizeof(keyword) is */ \ | |
| 1195 /* strlen(keyword) plus 1 for the NUL char. */ \ | |
| 1196 const int keyword_length = sizeof(keyword) - 1; \ | |
| 1197 STATIC_ASSERT(keyword_length >= kMinLength); \ | |
| 1198 STATIC_ASSERT(keyword_length <= kMaxLength); \ | |
| 1199 if (input_length == keyword_length && input[1] == keyword[1] && \ | |
| 1200 (keyword_length <= 2 || input[2] == keyword[2]) && \ | |
| 1201 (keyword_length <= 3 || input[3] == keyword[3]) && \ | |
| 1202 (keyword_length <= 4 || input[4] == keyword[4]) && \ | |
| 1203 (keyword_length <= 5 || input[5] == keyword[5]) && \ | |
| 1204 (keyword_length <= 6 || input[6] == keyword[6]) && \ | |
| 1205 (keyword_length <= 7 || input[7] == keyword[7]) && \ | |
| 1206 (keyword_length <= 8 || input[8] == keyword[8]) && \ | |
| 1207 (keyword_length <= 9 || input[9] == keyword[9])) { \ | |
| 1208 if (escaped) { \ | |
| 1209 return token == Token::FUTURE_STRICT_RESERVED_WORD \ | |
| 1210 ? Token::ESCAPED_STRICT_RESERVED_WORD \ | |
| 1211 : Token::ESCAPED_KEYWORD; \ | |
| 1212 } \ | |
| 1213 return token; \ | |
| 1214 } \ | |
| 1215 } | |
| 1216 KEYWORDS(KEYWORD_GROUP_CASE, KEYWORD) | |
| 1217 } | |
| 1218 return Token::IDENTIFIER; | |
| 1219 } | |
| 1220 | |
| 1221 | |
| 1222 bool Scanner::IdentifierIsFutureStrictReserved( | |
| 1223 const AstRawString* string) const { | |
| 1224 // Keywords are always 1-byte strings. | |
| 1225 if (!string->is_one_byte()) return false; | |
| 1226 if (string->IsOneByteEqualTo("let") || string->IsOneByteEqualTo("static") || | |
| 1227 string->IsOneByteEqualTo("yield")) { | |
| 1228 return true; | |
| 1229 } | |
| 1230 return Token::FUTURE_STRICT_RESERVED_WORD == | |
| 1231 KeywordOrIdentifierToken(string->raw_data(), string->length(), false); | |
| 1232 } | |
| 1233 | |
| 1234 | |
| 1235 Token::Value Scanner::ScanIdentifierOrKeyword() { | |
| 1236 DCHECK(unicode_cache_->IsIdentifierStart(c0_)); | |
| 1237 LiteralScope literal(this); | |
| 1238 if (IsInRange(c0_, 'a', 'z')) { | |
| 1239 do { | |
| 1240 uc32 first_char = c0_; | |
| 1241 Advance<false, false>(); | |
| 1242 AddLiteralChar(first_char); | |
| 1243 } while (IsInRange(c0_, 'a', 'z')); | |
| 1244 | |
| 1245 if (IsDecimalDigit(c0_) || IsInRange(c0_, 'A', 'Z') || c0_ == '_' || | |
| 1246 c0_ == '$') { | |
| 1247 // Identifier starting with lowercase. | |
| 1248 uc32 first_char = c0_; | |
| 1249 Advance<false, false>(); | |
| 1250 AddLiteralChar(first_char); | |
| 1251 while (IsAsciiIdentifier(c0_)) { | |
| 1252 uc32 first_char = c0_; | |
| 1253 Advance<false, false>(); | |
| 1254 AddLiteralChar(first_char); | |
| 1255 } | |
| 1256 if (c0_ <= kMaxAscii && c0_ != '\\') { | |
| 1257 literal.Complete(); | |
| 1258 return Token::IDENTIFIER; | |
| 1259 } | |
| 1260 } else if (c0_ <= kMaxAscii && c0_ != '\\') { | |
| 1261 // Only a-z+: could be a keyword or identifier. | |
| 1262 literal.Complete(); | |
| 1263 Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal(); | |
| 1264 return KeywordOrIdentifierToken(chars.start(), chars.length(), false); | |
| 1265 } | |
| 1266 | |
| 1267 HandleLeadSurrogate(); | |
| 1268 } else if (IsInRange(c0_, 'A', 'Z') || c0_ == '_' || c0_ == '$') { | |
| 1269 do { | |
| 1270 uc32 first_char = c0_; | |
| 1271 Advance<false, false>(); | |
| 1272 AddLiteralChar(first_char); | |
| 1273 } while (IsAsciiIdentifier(c0_)); | |
| 1274 | |
| 1275 if (c0_ <= kMaxAscii && c0_ != '\\') { | |
| 1276 literal.Complete(); | |
| 1277 return Token::IDENTIFIER; | |
| 1278 } | |
| 1279 | |
| 1280 HandleLeadSurrogate(); | |
| 1281 } else if (c0_ == '\\') { | |
| 1282 // Scan identifier start character. | |
| 1283 uc32 c = ScanIdentifierUnicodeEscape(); | |
| 1284 // Only allow legal identifier start characters. | |
| 1285 if (c < 0 || | |
| 1286 c == '\\' || // No recursive escapes. | |
| 1287 !unicode_cache_->IsIdentifierStart(c)) { | |
| 1288 return Token::ILLEGAL; | |
| 1289 } | |
| 1290 AddLiteralChar(c); | |
| 1291 return ScanIdentifierSuffix(&literal, true); | |
| 1292 } else { | |
| 1293 uc32 first_char = c0_; | |
| 1294 Advance(); | |
| 1295 AddLiteralChar(first_char); | |
| 1296 } | |
| 1297 | |
| 1298 // Scan the rest of the identifier characters. | |
| 1299 while (c0_ >= 0 && unicode_cache_->IsIdentifierPart(c0_)) { | |
| 1300 if (c0_ != '\\') { | |
| 1301 uc32 next_char = c0_; | |
| 1302 Advance(); | |
| 1303 AddLiteralChar(next_char); | |
| 1304 continue; | |
| 1305 } | |
| 1306 // Fallthrough if no longer able to complete keyword. | |
| 1307 return ScanIdentifierSuffix(&literal, false); | |
| 1308 } | |
| 1309 | |
| 1310 literal.Complete(); | |
| 1311 | |
| 1312 if (next_.literal_chars->is_one_byte()) { | |
| 1313 Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal(); | |
| 1314 return KeywordOrIdentifierToken(chars.start(), chars.length(), false); | |
| 1315 } | |
| 1316 return Token::IDENTIFIER; | |
| 1317 } | |
| 1318 | |
| 1319 | |
| 1320 Token::Value Scanner::ScanIdentifierSuffix(LiteralScope* literal, | |
| 1321 bool escaped) { | |
| 1322 // Scan the rest of the identifier characters. | |
| 1323 while (c0_ >= 0 && unicode_cache_->IsIdentifierPart(c0_)) { | |
| 1324 if (c0_ == '\\') { | |
| 1325 uc32 c = ScanIdentifierUnicodeEscape(); | |
| 1326 escaped = true; | |
| 1327 // Only allow legal identifier part characters. | |
| 1328 if (c < 0 || | |
| 1329 c == '\\' || | |
| 1330 !unicode_cache_->IsIdentifierPart(c)) { | |
| 1331 return Token::ILLEGAL; | |
| 1332 } | |
| 1333 AddLiteralChar(c); | |
| 1334 } else { | |
| 1335 AddLiteralChar(c0_); | |
| 1336 Advance(); | |
| 1337 } | |
| 1338 } | |
| 1339 literal->Complete(); | |
| 1340 | |
| 1341 if (escaped && next_.literal_chars->is_one_byte()) { | |
| 1342 Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal(); | |
| 1343 return KeywordOrIdentifierToken(chars.start(), chars.length(), true); | |
| 1344 } | |
| 1345 return Token::IDENTIFIER; | |
| 1346 } | |
| 1347 | |
| 1348 | |
| 1349 bool Scanner::ScanRegExpPattern(bool seen_equal) { | |
| 1350 // Scan: ('/' | '/=') RegularExpressionBody '/' RegularExpressionFlags | |
| 1351 bool in_character_class = false; | |
| 1352 | |
| 1353 // Previous token is either '/' or '/=', in the second case, the | |
| 1354 // pattern starts at =. | |
| 1355 next_.location.beg_pos = source_pos() - (seen_equal ? 2 : 1); | |
| 1356 next_.location.end_pos = source_pos() - (seen_equal ? 1 : 0); | |
| 1357 | |
| 1358 // Scan regular expression body: According to ECMA-262, 3rd, 7.8.5, | |
| 1359 // the scanner should pass uninterpreted bodies to the RegExp | |
| 1360 // constructor. | |
| 1361 LiteralScope literal(this); | |
| 1362 if (seen_equal) { | |
| 1363 AddLiteralChar('='); | |
| 1364 } | |
| 1365 | |
| 1366 while (c0_ != '/' || in_character_class) { | |
| 1367 if (c0_ < 0 || unicode_cache_->IsLineTerminator(c0_)) return false; | |
| 1368 if (c0_ == '\\') { // Escape sequence. | |
| 1369 AddLiteralCharAdvance(); | |
| 1370 if (c0_ < 0 || unicode_cache_->IsLineTerminator(c0_)) return false; | |
| 1371 AddLiteralCharAdvance(); | |
| 1372 // If the escape allows more characters, i.e., \x??, \u????, or \c?, | |
| 1373 // only "safe" characters are allowed (letters, digits, underscore), | |
| 1374 // otherwise the escape isn't valid and the invalid character has | |
| 1375 // its normal meaning. I.e., we can just continue scanning without | |
| 1376 // worrying whether the following characters are part of the escape | |
| 1377 // or not, since any '/', '\\' or '[' is guaranteed to not be part | |
| 1378 // of the escape sequence. | |
| 1379 | |
| 1380 // TODO(896): At some point, parse RegExps more throughly to capture | |
| 1381 // octal esacpes in strict mode. | |
| 1382 } else { // Unescaped character. | |
| 1383 if (c0_ == '[') in_character_class = true; | |
| 1384 if (c0_ == ']') in_character_class = false; | |
| 1385 AddLiteralCharAdvance(); | |
| 1386 } | |
| 1387 } | |
| 1388 Advance(); // consume '/' | |
| 1389 | |
| 1390 literal.Complete(); | |
| 1391 | |
| 1392 return true; | |
| 1393 } | |
| 1394 | |
| 1395 | |
| 1396 Maybe<RegExp::Flags> Scanner::ScanRegExpFlags() { | |
| 1397 // Scan regular expression flags. | |
| 1398 LiteralScope literal(this); | |
| 1399 int flags = 0; | |
| 1400 while (c0_ >= 0 && unicode_cache_->IsIdentifierPart(c0_)) { | |
| 1401 RegExp::Flags flag = RegExp::kNone; | |
| 1402 switch (c0_) { | |
| 1403 case 'g': | |
| 1404 flag = RegExp::kGlobal; | |
| 1405 break; | |
| 1406 case 'i': | |
| 1407 flag = RegExp::kIgnoreCase; | |
| 1408 break; | |
| 1409 case 'm': | |
| 1410 flag = RegExp::kMultiline; | |
| 1411 break; | |
| 1412 case 'u': | |
| 1413 if (!FLAG_harmony_unicode_regexps) return Nothing<RegExp::Flags>(); | |
| 1414 flag = RegExp::kUnicode; | |
| 1415 break; | |
| 1416 case 'y': | |
| 1417 if (!FLAG_harmony_regexps) return Nothing<RegExp::Flags>(); | |
| 1418 flag = RegExp::kSticky; | |
| 1419 break; | |
| 1420 default: | |
| 1421 return Nothing<RegExp::Flags>(); | |
| 1422 } | |
| 1423 if (flags & flag) return Nothing<RegExp::Flags>(); | |
| 1424 AddLiteralCharAdvance(); | |
| 1425 flags |= flag; | |
| 1426 } | |
| 1427 literal.Complete(); | |
| 1428 | |
| 1429 next_.location.end_pos = source_pos(); | |
| 1430 return Just(RegExp::Flags(flags)); | |
| 1431 } | |
| 1432 | |
| 1433 | |
| 1434 const AstRawString* Scanner::CurrentSymbol(AstValueFactory* ast_value_factory) { | |
| 1435 if (is_literal_one_byte()) { | |
| 1436 return ast_value_factory->GetOneByteString(literal_one_byte_string()); | |
| 1437 } | |
| 1438 return ast_value_factory->GetTwoByteString(literal_two_byte_string()); | |
| 1439 } | |
| 1440 | |
| 1441 | |
| 1442 const AstRawString* Scanner::NextSymbol(AstValueFactory* ast_value_factory) { | |
| 1443 if (is_next_literal_one_byte()) { | |
| 1444 return ast_value_factory->GetOneByteString(next_literal_one_byte_string()); | |
| 1445 } | |
| 1446 return ast_value_factory->GetTwoByteString(next_literal_two_byte_string()); | |
| 1447 } | |
| 1448 | |
| 1449 | |
| 1450 const AstRawString* Scanner::CurrentRawSymbol( | |
| 1451 AstValueFactory* ast_value_factory) { | |
| 1452 if (is_raw_literal_one_byte()) { | |
| 1453 return ast_value_factory->GetOneByteString(raw_literal_one_byte_string()); | |
| 1454 } | |
| 1455 return ast_value_factory->GetTwoByteString(raw_literal_two_byte_string()); | |
| 1456 } | |
| 1457 | |
| 1458 | |
| 1459 double Scanner::DoubleValue() { | |
| 1460 DCHECK(is_literal_one_byte()); | |
| 1461 return StringToDouble( | |
| 1462 unicode_cache_, | |
| 1463 literal_one_byte_string(), | |
| 1464 ALLOW_HEX | ALLOW_OCTAL | ALLOW_IMPLICIT_OCTAL | ALLOW_BINARY); | |
| 1465 } | |
| 1466 | |
| 1467 | |
| 1468 bool Scanner::ContainsDot() { | |
| 1469 DCHECK(is_literal_one_byte()); | |
| 1470 Vector<const uint8_t> str = literal_one_byte_string(); | |
| 1471 return std::find(str.begin(), str.end(), '.') != str.end(); | |
| 1472 } | |
| 1473 | |
| 1474 | |
| 1475 int Scanner::FindSymbol(DuplicateFinder* finder, int value) { | |
| 1476 if (is_literal_one_byte()) { | |
| 1477 return finder->AddOneByteSymbol(literal_one_byte_string(), value); | |
| 1478 } | |
| 1479 return finder->AddTwoByteSymbol(literal_two_byte_string(), value); | |
| 1480 } | |
| 1481 | |
| 1482 | |
| 1483 bool Scanner::SetBookmark() { | |
| 1484 if (c0_ != kNoBookmark && bookmark_c0_ == kNoBookmark && | |
| 1485 next_next_.token == Token::UNINITIALIZED && source_->SetBookmark()) { | |
| 1486 bookmark_c0_ = c0_; | |
| 1487 CopyTokenDesc(&bookmark_current_, ¤t_); | |
| 1488 CopyTokenDesc(&bookmark_next_, &next_); | |
| 1489 return true; | |
| 1490 } | |
| 1491 return false; | |
| 1492 } | |
| 1493 | |
| 1494 | |
| 1495 void Scanner::ResetToBookmark() { | |
| 1496 DCHECK(BookmarkHasBeenSet()); // Caller hasn't called SetBookmark. | |
| 1497 | |
| 1498 source_->ResetToBookmark(); | |
| 1499 c0_ = bookmark_c0_; | |
| 1500 StartLiteral(); | |
| 1501 StartRawLiteral(); | |
| 1502 CopyTokenDesc(&next_, &bookmark_current_); | |
| 1503 current_ = next_; | |
| 1504 StartLiteral(); | |
| 1505 StartRawLiteral(); | |
| 1506 CopyTokenDesc(&next_, &bookmark_next_); | |
| 1507 | |
| 1508 bookmark_c0_ = kBookmarkWasApplied; | |
| 1509 } | |
| 1510 | |
| 1511 | |
| 1512 bool Scanner::BookmarkHasBeenSet() { return bookmark_c0_ >= 0; } | |
| 1513 | |
| 1514 | |
| 1515 bool Scanner::BookmarkHasBeenReset() { | |
| 1516 return bookmark_c0_ == kBookmarkWasApplied; | |
| 1517 } | |
| 1518 | |
| 1519 | |
| 1520 void Scanner::DropBookmark() { bookmark_c0_ = kNoBookmark; } | |
| 1521 | |
| 1522 | |
| 1523 void Scanner::CopyTokenDesc(TokenDesc* to, TokenDesc* from) { | |
| 1524 DCHECK_NOT_NULL(to); | |
| 1525 DCHECK_NOT_NULL(from); | |
| 1526 to->token = from->token; | |
| 1527 to->location = from->location; | |
| 1528 to->literal_chars->CopyFrom(from->literal_chars); | |
| 1529 to->raw_literal_chars->CopyFrom(from->raw_literal_chars); | |
| 1530 } | |
| 1531 | |
| 1532 | |
| 1533 int DuplicateFinder::AddOneByteSymbol(Vector<const uint8_t> key, int value) { | |
| 1534 return AddSymbol(key, true, value); | |
| 1535 } | |
| 1536 | |
| 1537 | |
| 1538 int DuplicateFinder::AddTwoByteSymbol(Vector<const uint16_t> key, int value) { | |
| 1539 return AddSymbol(Vector<const uint8_t>::cast(key), false, value); | |
| 1540 } | |
| 1541 | |
| 1542 | |
| 1543 int DuplicateFinder::AddSymbol(Vector<const uint8_t> key, | |
| 1544 bool is_one_byte, | |
| 1545 int value) { | |
| 1546 uint32_t hash = Hash(key, is_one_byte); | |
| 1547 byte* encoding = BackupKey(key, is_one_byte); | |
| 1548 HashMap::Entry* entry = map_.LookupOrInsert(encoding, hash); | |
| 1549 int old_value = static_cast<int>(reinterpret_cast<intptr_t>(entry->value)); | |
| 1550 entry->value = | |
| 1551 reinterpret_cast<void*>(static_cast<intptr_t>(value | old_value)); | |
| 1552 return old_value; | |
| 1553 } | |
| 1554 | |
| 1555 | |
| 1556 int DuplicateFinder::AddNumber(Vector<const uint8_t> key, int value) { | |
| 1557 DCHECK(key.length() > 0); | |
| 1558 // Quick check for already being in canonical form. | |
| 1559 if (IsNumberCanonical(key)) { | |
| 1560 return AddOneByteSymbol(key, value); | |
| 1561 } | |
| 1562 | |
| 1563 int flags = ALLOW_HEX | ALLOW_OCTAL | ALLOW_IMPLICIT_OCTAL | ALLOW_BINARY; | |
| 1564 double double_value = StringToDouble( | |
| 1565 unicode_constants_, key, flags, 0.0); | |
| 1566 int length; | |
| 1567 const char* string; | |
| 1568 if (!std::isfinite(double_value)) { | |
| 1569 string = "Infinity"; | |
| 1570 length = 8; // strlen("Infinity"); | |
| 1571 } else { | |
| 1572 string = DoubleToCString(double_value, | |
| 1573 Vector<char>(number_buffer_, kBufferSize)); | |
| 1574 length = StrLength(string); | |
| 1575 } | |
| 1576 return AddSymbol(Vector<const byte>(reinterpret_cast<const byte*>(string), | |
| 1577 length), true, value); | |
| 1578 } | |
| 1579 | |
| 1580 | |
| 1581 bool DuplicateFinder::IsNumberCanonical(Vector<const uint8_t> number) { | |
| 1582 // Test for a safe approximation of number literals that are already | |
| 1583 // in canonical form: max 15 digits, no leading zeroes, except an | |
| 1584 // integer part that is a single zero, and no trailing zeros below | |
| 1585 // the decimal point. | |
| 1586 int pos = 0; | |
| 1587 int length = number.length(); | |
| 1588 if (number.length() > 15) return false; | |
| 1589 if (number[pos] == '0') { | |
| 1590 pos++; | |
| 1591 } else { | |
| 1592 while (pos < length && | |
| 1593 static_cast<unsigned>(number[pos] - '0') <= ('9' - '0')) pos++; | |
| 1594 } | |
| 1595 if (length == pos) return true; | |
| 1596 if (number[pos] != '.') return false; | |
| 1597 pos++; | |
| 1598 bool invalid_last_digit = true; | |
| 1599 while (pos < length) { | |
| 1600 uint8_t digit = number[pos] - '0'; | |
| 1601 if (digit > '9' - '0') return false; | |
| 1602 invalid_last_digit = (digit == 0); | |
| 1603 pos++; | |
| 1604 } | |
| 1605 return !invalid_last_digit; | |
| 1606 } | |
| 1607 | |
| 1608 | |
| 1609 uint32_t DuplicateFinder::Hash(Vector<const uint8_t> key, bool is_one_byte) { | |
| 1610 // Primitive hash function, almost identical to the one used | |
| 1611 // for strings (except that it's seeded by the length and representation). | |
| 1612 int length = key.length(); | |
| 1613 uint32_t hash = (length << 1) | (is_one_byte ? 1 : 0); | |
| 1614 for (int i = 0; i < length; i++) { | |
| 1615 uint32_t c = key[i]; | |
| 1616 hash = (hash + c) * 1025; | |
| 1617 hash ^= (hash >> 6); | |
| 1618 } | |
| 1619 return hash; | |
| 1620 } | |
| 1621 | |
| 1622 | |
| 1623 bool DuplicateFinder::Match(void* first, void* second) { | |
| 1624 // Decode lengths. | |
| 1625 // Length + representation is encoded as base 128, most significant heptet | |
| 1626 // first, with a 8th bit being non-zero while there are more heptets. | |
| 1627 // The value encodes the number of bytes following, and whether the original | |
| 1628 // was Latin1. | |
| 1629 byte* s1 = reinterpret_cast<byte*>(first); | |
| 1630 byte* s2 = reinterpret_cast<byte*>(second); | |
| 1631 uint32_t length_one_byte_field = 0; | |
| 1632 byte c1; | |
| 1633 do { | |
| 1634 c1 = *s1; | |
| 1635 if (c1 != *s2) return false; | |
| 1636 length_one_byte_field = (length_one_byte_field << 7) | (c1 & 0x7f); | |
| 1637 s1++; | |
| 1638 s2++; | |
| 1639 } while ((c1 & 0x80) != 0); | |
| 1640 int length = static_cast<int>(length_one_byte_field >> 1); | |
| 1641 return memcmp(s1, s2, length) == 0; | |
| 1642 } | |
| 1643 | |
| 1644 | |
| 1645 byte* DuplicateFinder::BackupKey(Vector<const uint8_t> bytes, | |
| 1646 bool is_one_byte) { | |
| 1647 uint32_t one_byte_length = (bytes.length() << 1) | (is_one_byte ? 1 : 0); | |
| 1648 backing_store_.StartSequence(); | |
| 1649 // Emit one_byte_length as base-128 encoded number, with the 7th bit set | |
| 1650 // on the byte of every heptet except the last, least significant, one. | |
| 1651 if (one_byte_length >= (1 << 7)) { | |
| 1652 if (one_byte_length >= (1 << 14)) { | |
| 1653 if (one_byte_length >= (1 << 21)) { | |
| 1654 if (one_byte_length >= (1 << 28)) { | |
| 1655 backing_store_.Add( | |
| 1656 static_cast<uint8_t>((one_byte_length >> 28) | 0x80)); | |
| 1657 } | |
| 1658 backing_store_.Add( | |
| 1659 static_cast<uint8_t>((one_byte_length >> 21) | 0x80u)); | |
| 1660 } | |
| 1661 backing_store_.Add( | |
| 1662 static_cast<uint8_t>((one_byte_length >> 14) | 0x80u)); | |
| 1663 } | |
| 1664 backing_store_.Add(static_cast<uint8_t>((one_byte_length >> 7) | 0x80u)); | |
| 1665 } | |
| 1666 backing_store_.Add(static_cast<uint8_t>(one_byte_length & 0x7f)); | |
| 1667 | |
| 1668 backing_store_.AddBlock(bytes); | |
| 1669 return backing_store_.EndSequence().start(); | |
| 1670 } | |
| 1671 | |
| 1672 } // namespace internal | |
| 1673 } // namespace v8 | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 1481613002:
Create ast/ and parsing/ subdirectories and move appropriate files (Closed)
Base URL: https://chromium.googlesource.com/v8/v8.git@master