| // Copyright 2011 the V8 project authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| // Features shared by parsing and pre-parsing scanners. |
| |
| #include "src/parsing/scanner.h" |
| |
| #include <stdint.h> |
| |
| #include <cmath> |
| |
| #include "src/ast/ast-value-factory.h" |
| #include "src/char-predicates-inl.h" |
| #include "src/conversions-inl.h" |
| #include "src/objects/bigint.h" |
| #include "src/parsing/duplicate-finder.h" // For Scanner::FindSymbol |
| #include "src/unicode-cache-inl.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| class Scanner::ErrorState { |
| public: |
| ErrorState(MessageTemplate::Template* message_stack, |
| Scanner::Location* location_stack) |
| : message_stack_(message_stack), |
| old_message_(*message_stack), |
| location_stack_(location_stack), |
| old_location_(*location_stack) { |
| *message_stack_ = MessageTemplate::kNone; |
| *location_stack_ = Location::invalid(); |
| } |
| |
| ~ErrorState() { |
| *message_stack_ = old_message_; |
| *location_stack_ = old_location_; |
| } |
| |
| void MoveErrorTo(TokenDesc* dest) { |
| if (*message_stack_ == MessageTemplate::kNone) { |
| return; |
| } |
| if (dest->invalid_template_escape_message == MessageTemplate::kNone) { |
| dest->invalid_template_escape_message = *message_stack_; |
| dest->invalid_template_escape_location = *location_stack_; |
| } |
| *message_stack_ = MessageTemplate::kNone; |
| *location_stack_ = Location::invalid(); |
| } |
| |
| private: |
| MessageTemplate::Template* const message_stack_; |
| MessageTemplate::Template const old_message_; |
| Scanner::Location* const location_stack_; |
| Scanner::Location const old_location_; |
| }; |
| |
| // ---------------------------------------------------------------------------- |
| // Scanner::LiteralBuffer |
| |
| Handle<String> Scanner::LiteralBuffer::Internalize(Isolate* isolate) const { |
| if (is_one_byte()) { |
| return isolate->factory()->InternalizeOneByteString(one_byte_literal()); |
| } |
| return isolate->factory()->InternalizeTwoByteString(two_byte_literal()); |
| } |
| |
| int Scanner::LiteralBuffer::NewCapacity(int min_capacity) { |
| int capacity = Max(min_capacity, backing_store_.length()); |
| int new_capacity = Min(capacity * kGrowthFactory, capacity + kMaxGrowth); |
| return new_capacity; |
| } |
| |
| void Scanner::LiteralBuffer::ExpandBuffer() { |
| Vector<byte> new_store = Vector<byte>::New(NewCapacity(kInitialCapacity)); |
| MemCopy(new_store.start(), backing_store_.start(), position_); |
| backing_store_.Dispose(); |
| backing_store_ = new_store; |
| } |
| |
| void Scanner::LiteralBuffer::ConvertToTwoByte() { |
| DCHECK(is_one_byte_); |
| Vector<byte> new_store; |
| int new_content_size = position_ * kUC16Size; |
| if (new_content_size >= backing_store_.length()) { |
| // Ensure room for all currently read code units as UC16 as well |
| // as the code unit about to be stored. |
| new_store = Vector<byte>::New(NewCapacity(new_content_size)); |
| } else { |
| new_store = backing_store_; |
| } |
| uint8_t* src = backing_store_.start(); |
| uint16_t* dst = reinterpret_cast<uint16_t*>(new_store.start()); |
| for (int i = position_ - 1; i >= 0; i--) { |
| dst[i] = src[i]; |
| } |
| if (new_store.start() != backing_store_.start()) { |
| backing_store_.Dispose(); |
| backing_store_ = new_store; |
| } |
| position_ = new_content_size; |
| is_one_byte_ = false; |
| } |
| |
| void Scanner::LiteralBuffer::AddCharSlow(uc32 code_unit) { |
| if (position_ >= backing_store_.length()) ExpandBuffer(); |
| if (is_one_byte_) { |
| if (code_unit <= static_cast<uc32>(unibrow::Latin1::kMaxChar)) { |
| backing_store_[position_] = static_cast<byte>(code_unit); |
| position_ += kOneByteSize; |
| return; |
| } |
| ConvertToTwoByte(); |
| } |
| if (code_unit <= |
| static_cast<uc32>(unibrow::Utf16::kMaxNonSurrogateCharCode)) { |
| *reinterpret_cast<uint16_t*>(&backing_store_[position_]) = code_unit; |
| position_ += kUC16Size; |
| } else { |
| *reinterpret_cast<uint16_t*>(&backing_store_[position_]) = |
| unibrow::Utf16::LeadSurrogate(code_unit); |
| position_ += kUC16Size; |
| if (position_ >= backing_store_.length()) ExpandBuffer(); |
| *reinterpret_cast<uint16_t*>(&backing_store_[position_]) = |
| unibrow::Utf16::TrailSurrogate(code_unit); |
| position_ += kUC16Size; |
| } |
| } |
| |
| // ---------------------------------------------------------------------------- |
| // Scanner::BookmarkScope |
| |
| const size_t Scanner::BookmarkScope::kBookmarkAtFirstPos = |
| std::numeric_limits<size_t>::max() - 2; |
| const size_t Scanner::BookmarkScope::kNoBookmark = |
| std::numeric_limits<size_t>::max() - 1; |
| const size_t Scanner::BookmarkScope::kBookmarkWasApplied = |
| std::numeric_limits<size_t>::max(); |
| |
| void Scanner::BookmarkScope::Set() { |
| DCHECK_EQ(bookmark_, kNoBookmark); |
| DCHECK_EQ(scanner_->next_next_.token, Token::UNINITIALIZED); |
| |
| // The first token is a bit special, since current_ will still be |
| // uninitialized. In this case, store kBookmarkAtFirstPos and special-case it |
| // when |
| // applying the bookmark. |
| DCHECK_IMPLIES( |
| scanner_->current_.token == Token::UNINITIALIZED, |
| scanner_->current_.location.beg_pos == scanner_->next_.location.beg_pos); |
| bookmark_ = (scanner_->current_.token == Token::UNINITIALIZED) |
| ? kBookmarkAtFirstPos |
| : scanner_->location().beg_pos; |
| } |
| |
| void Scanner::BookmarkScope::Apply() { |
| DCHECK(HasBeenSet()); // Caller hasn't called SetBookmark. |
| if (bookmark_ == kBookmarkAtFirstPos) { |
| scanner_->SeekNext(0); |
| } else { |
| scanner_->SeekNext(bookmark_); |
| scanner_->Next(); |
| DCHECK_EQ(scanner_->location().beg_pos, static_cast<int>(bookmark_)); |
| } |
| bookmark_ = kBookmarkWasApplied; |
| } |
| |
| bool Scanner::BookmarkScope::HasBeenSet() { |
| return bookmark_ != kNoBookmark && bookmark_ != kBookmarkWasApplied; |
| } |
| |
| bool Scanner::BookmarkScope::HasBeenApplied() { |
| return bookmark_ == kBookmarkWasApplied; |
| } |
| |
| // ---------------------------------------------------------------------------- |
| // Scanner |
| |
| Scanner::Scanner(UnicodeCache* unicode_cache) |
| : unicode_cache_(unicode_cache), |
| octal_pos_(Location::invalid()), |
| octal_message_(MessageTemplate::kNone), |
| found_html_comment_(false), |
| allow_harmony_bigint_(false) {} |
| |
| void Scanner::Initialize(Utf16CharacterStream* source, bool is_module) { |
| DCHECK_NOT_NULL(source); |
| source_ = source; |
| is_module_ = is_module; |
| // Need to capture identifiers in order to recognize "get" and "set" |
| // in object literals. |
| Init(); |
| has_line_terminator_before_next_ = true; |
| Scan(); |
| } |
| |
| template <bool capture_raw, bool unicode> |
| uc32 Scanner::ScanHexNumber(int expected_length) { |
| DCHECK_LE(expected_length, 4); // prevent overflow |
| |
| int begin = source_pos() - 2; |
| uc32 x = 0; |
| for (int i = 0; i < expected_length; i++) { |
| int d = HexValue(c0_); |
| if (d < 0) { |
| ReportScannerError(Location(begin, begin + expected_length + 2), |
| unicode |
| ? MessageTemplate::kInvalidUnicodeEscapeSequence |
| : MessageTemplate::kInvalidHexEscapeSequence); |
| return -1; |
| } |
| x = x * 16 + d; |
| Advance<capture_raw>(); |
| } |
| |
| return x; |
| } |
| |
| template <bool capture_raw> |
| uc32 Scanner::ScanUnlimitedLengthHexNumber(int max_value, int beg_pos) { |
| uc32 x = 0; |
| int d = HexValue(c0_); |
| if (d < 0) return -1; |
| |
| while (d >= 0) { |
| x = x * 16 + d; |
| if (x > max_value) { |
| ReportScannerError(Location(beg_pos, source_pos() + 1), |
| MessageTemplate::kUndefinedUnicodeCodePoint); |
| return -1; |
| } |
| Advance<capture_raw>(); |
| d = HexValue(c0_); |
| } |
| |
| return x; |
| } |
| |
| |
| // Ensure that tokens can be stored in a byte. |
| STATIC_ASSERT(Token::NUM_TOKENS <= 0x100); |
| |
| // Table of one-character tokens, by character (0x00..0x7F only). |
| // clang-format off |
| static const byte one_char_tokens[] = { |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::LPAREN, // 0x28 |
| Token::RPAREN, // 0x29 |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::COMMA, // 0x2C |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::COLON, // 0x3A |
| Token::SEMICOLON, // 0x3B |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::CONDITIONAL, // 0x3F |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::LBRACK, // 0x5B |
| Token::ILLEGAL, |
| Token::RBRACK, // 0x5D |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::ILLEGAL, |
| Token::LBRACE, // 0x7B |
| Token::ILLEGAL, |
| Token::RBRACE, // 0x7D |
| Token::BIT_NOT, // 0x7E |
| Token::ILLEGAL |
| }; |
| // clang-format on |
| |
| Token::Value Scanner::Next() { |
| if (next_.token == Token::EOS) { |
| next_.location.beg_pos = current_.location.beg_pos; |
| next_.location.end_pos = current_.location.end_pos; |
| } |
| current_ = next_; |
| if (V8_UNLIKELY(next_next_.token != Token::UNINITIALIZED)) { |
| next_ = next_next_; |
| next_next_.token = Token::UNINITIALIZED; |
| next_next_.contextual_token = Token::UNINITIALIZED; |
| has_line_terminator_before_next_ = has_line_terminator_after_next_; |
| return current_.token; |
| } |
| has_line_terminator_before_next_ = false; |
| has_multiline_comment_before_next_ = false; |
| if (static_cast<unsigned>(c0_) <= 0x7F) { |
| Token::Value token = static_cast<Token::Value>(one_char_tokens[c0_]); |
| if (token != Token::ILLEGAL) { |
| int pos = source_pos(); |
| next_.token = token; |
| next_.contextual_token = Token::UNINITIALIZED; |
| next_.location.beg_pos = pos; |
| next_.location.end_pos = pos + 1; |
| next_.literal_chars = nullptr; |
| next_.raw_literal_chars = nullptr; |
| next_.invalid_template_escape_message = MessageTemplate::kNone; |
| Advance(); |
| return current_.token; |
| } |
| } |
| Scan(); |
| return current_.token; |
| } |
| |
| |
| Token::Value Scanner::PeekAhead() { |
| DCHECK(next_.token != Token::DIV); |
| DCHECK(next_.token != Token::ASSIGN_DIV); |
| |
| if (next_next_.token != Token::UNINITIALIZED) { |
| return next_next_.token; |
| } |
| TokenDesc prev = current_; |
| bool has_line_terminator_before_next = |
| has_line_terminator_before_next_ || has_multiline_comment_before_next_; |
| Next(); |
| has_line_terminator_after_next_ = |
| has_line_terminator_before_next_ || has_multiline_comment_before_next_; |
| has_line_terminator_before_next_ = has_line_terminator_before_next; |
| Token::Value ret = next_.token; |
| next_next_ = next_; |
| next_ = current_; |
| current_ = prev; |
| return ret; |
| } |
| |
| |
| Token::Value Scanner::SkipWhiteSpace() { |
| int start_position = source_pos(); |
| |
| while (true) { |
| while (true) { |
| // Don't skip behind the end of input. |
| if (c0_ == kEndOfInput) break; |
| |
| // Advance as long as character is a WhiteSpace or LineTerminator. |
| // Remember if the latter is the case. |
| if (unibrow::IsLineTerminator(c0_)) { |
| has_line_terminator_before_next_ = true; |
| } else if (!unicode_cache_->IsWhiteSpace(c0_)) { |
| break; |
| } |
| Advance(); |
| } |
| |
| // If there is an HTML comment end '-->' at the beginning of a |
| // line (with only whitespace in front of it), we treat the rest |
| // of the line as a comment. This is in line with the way |
| // SpiderMonkey handles it. |
| if (c0_ != '-' || !has_line_terminator_before_next_) break; |
| |
| Advance(); |
| if (c0_ != '-') { |
| PushBack('-'); // undo Advance() |
| break; |
| } |
| |
| Advance(); |
| if (c0_ != '>') { |
| PushBack2('-', '-'); // undo 2x Advance(); |
| break; |
| } |
| |
| // Treat the rest of the line as a comment. |
| Token::Value token = SkipSingleHTMLComment(); |
| if (token == Token::ILLEGAL) { |
| return token; |
| } |
| } |
| |
| // Return whether or not we skipped any characters. |
| if (source_pos() == start_position) { |
| return Token::ILLEGAL; |
| } |
| |
| return Token::WHITESPACE; |
| } |
| |
| Token::Value Scanner::SkipSingleHTMLComment() { |
| if (is_module_) { |
| ReportScannerError(source_pos(), MessageTemplate::kHtmlCommentInModule); |
| return Token::ILLEGAL; |
| } |
| return SkipSingleLineComment(); |
| } |
| |
| Token::Value Scanner::SkipSingleLineComment() { |
| Advance(); |
| |
| // The line terminator at the end of the line is not considered |
| // to be part of the single-line comment; it is recognized |
| // separately by the lexical grammar and becomes part of the |
| // stream of input elements for the syntactic grammar (see |
| // ECMA-262, section 7.4). |
| while (c0_ != kEndOfInput && !unibrow::IsLineTerminator(c0_)) { |
| Advance(); |
| } |
| |
| return Token::WHITESPACE; |
| } |
| |
| |
| Token::Value Scanner::SkipSourceURLComment() { |
| TryToParseSourceURLComment(); |
| while (c0_ != kEndOfInput && !unibrow::IsLineTerminator(c0_)) { |
| Advance(); |
| } |
| |
| return Token::WHITESPACE; |
| } |
| |
| |
| void Scanner::TryToParseSourceURLComment() { |
| // Magic comments are of the form: //[#@]\s<name>=\s*<value>\s*.* and this |
| // function will just return if it cannot parse a magic comment. |
| if (c0_ == kEndOfInput || !unicode_cache_->IsWhiteSpace(c0_)) return; |
| Advance(); |
| LiteralBuffer name; |
| while (c0_ != kEndOfInput && |
| !unicode_cache_->IsWhiteSpaceOrLineTerminator(c0_) && c0_ != '=') { |
| name.AddChar(c0_); |
| Advance(); |
| } |
| if (!name.is_one_byte()) return; |
| Vector<const uint8_t> name_literal = name.one_byte_literal(); |
| LiteralBuffer* value; |
| if (name_literal == STATIC_CHAR_VECTOR("sourceURL")) { |
| value = &source_url_; |
| } else if (name_literal == STATIC_CHAR_VECTOR("sourceMappingURL")) { |
| value = &source_mapping_url_; |
| } else { |
| return; |
| } |
| if (c0_ != '=') |
| return; |
| Advance(); |
| value->Reset(); |
| while (c0_ != kEndOfInput && unicode_cache_->IsWhiteSpace(c0_)) { |
| Advance(); |
| } |
| while (c0_ != kEndOfInput && !unibrow::IsLineTerminator(c0_)) { |
| // Disallowed characters. |
| if (c0_ == '"' || c0_ == '\'') { |
| value->Reset(); |
| return; |
| } |
| if (unicode_cache_->IsWhiteSpace(c0_)) { |
| break; |
| } |
| value->AddChar(c0_); |
| Advance(); |
| } |
| // Allow whitespace at the end. |
| while (c0_ != kEndOfInput && !unibrow::IsLineTerminator(c0_)) { |
| if (!unicode_cache_->IsWhiteSpace(c0_)) { |
| value->Reset(); |
| break; |
| } |
| Advance(); |
| } |
| } |
| |
| |
| Token::Value Scanner::SkipMultiLineComment() { |
| DCHECK_EQ(c0_, '*'); |
| Advance(); |
| |
| while (c0_ != kEndOfInput) { |
| uc32 ch = c0_; |
| Advance(); |
| if (c0_ != kEndOfInput && unibrow::IsLineTerminator(ch)) { |
| // Following ECMA-262, section 7.4, a comment containing |
| // a newline will make the comment count as a line-terminator. |
| has_multiline_comment_before_next_ = true; |
| } |
| // If we have reached the end of the multi-line comment, we |
| // consume the '/' and insert a whitespace. This way all |
| // multi-line comments are treated as whitespace. |
| if (ch == '*' && c0_ == '/') { |
| c0_ = ' '; |
| return Token::WHITESPACE; |
| } |
| } |
| |
| // Unterminated multi-line comment. |
| return Token::ILLEGAL; |
| } |
| |
| Token::Value Scanner::ScanHtmlComment() { |
| // Check for <!-- comments. |
| DCHECK_EQ(c0_, '!'); |
| Advance(); |
| if (c0_ != '-') { |
| PushBack('!'); // undo Advance() |
| return Token::LT; |
| } |
| |
| Advance(); |
| if (c0_ != '-') { |
| PushBack2('-', '!'); // undo 2x Advance() |
| return Token::LT; |
| } |
| |
| found_html_comment_ = true; |
| return SkipSingleHTMLComment(); |
| } |
| |
| void Scanner::Scan() { |
| next_.literal_chars = nullptr; |
| next_.raw_literal_chars = nullptr; |
| next_.invalid_template_escape_message = MessageTemplate::kNone; |
| Token::Value token; |
| do { |
| // Remember the position of the next token |
| next_.location.beg_pos = source_pos(); |
| |
| switch (c0_) { |
| case ' ': |
| case '\t': |
| Advance(); |
| token = Token::WHITESPACE; |
| break; |
| |
| case '\n': |
| Advance(); |
| has_line_terminator_before_next_ = true; |
| token = Token::WHITESPACE; |
| break; |
| |
| case '"': |
| case '\'': |
| token = ScanString(); |
| break; |
| |
| case '<': |
| // < <= << <<= <!-- |
| Advance(); |
| if (c0_ == '=') { |
| token = Select(Token::LTE); |
| } else if (c0_ == '<') { |
| token = Select('=', Token::ASSIGN_SHL, Token::SHL); |
| } else if (c0_ == '!') { |
| token = ScanHtmlComment(); |
| } else { |
| token = Token::LT; |
| } |
| break; |
| |
| case '>': |
| // > >= >> >>= >>> >>>= |
| Advance(); |
| if (c0_ == '=') { |
| token = Select(Token::GTE); |
| } else if (c0_ == '>') { |
| // >> >>= >>> >>>= |
| Advance(); |
| if (c0_ == '=') { |
| token = Select(Token::ASSIGN_SAR); |
| } else if (c0_ == '>') { |
| token = Select('=', Token::ASSIGN_SHR, Token::SHR); |
| } else { |
| token = Token::SAR; |
| } |
| } else { |
| token = Token::GT; |
| } |
| break; |
| |
| case '=': |
| // = == === => |
| Advance(); |
| if (c0_ == '=') { |
| token = Select('=', Token::EQ_STRICT, Token::EQ); |
| } else if (c0_ == '>') { |
| token = Select(Token::ARROW); |
| } else { |
| token = Token::ASSIGN; |
| } |
| break; |
| |
| case '!': |
| // ! != !== |
| Advance(); |
| if (c0_ == '=') { |
| token = Select('=', Token::NE_STRICT, Token::NE); |
| } else { |
| token = Token::NOT; |
| } |
| break; |
| |
| case '+': |
| // + ++ += |
| Advance(); |
| if (c0_ == '+') { |
| token = Select(Token::INC); |
| } else if (c0_ == '=') { |
| token = Select(Token::ASSIGN_ADD); |
| } else { |
| token = Token::ADD; |
| } |
| break; |
| |
| case '-': |
| // - -- --> -= |
| Advance(); |
| if (c0_ == '-') { |
| Advance(); |
| if (c0_ == '>' && HasAnyLineTerminatorBeforeNext()) { |
| // For compatibility with SpiderMonkey, we skip lines that |
| // start with an HTML comment end '-->'. |
| token = SkipSingleHTMLComment(); |
| } else { |
| token = Token::DEC; |
| } |
| } else if (c0_ == '=') { |
| token = Select(Token::ASSIGN_SUB); |
| } else { |
| token = Token::SUB; |
| } |
| break; |
| |
| case '*': |
| // * *= |
| Advance(); |
| if (c0_ == '*') { |
| token = Select('=', Token::ASSIGN_EXP, Token::EXP); |
| } else if (c0_ == '=') { |
| token = Select(Token::ASSIGN_MUL); |
| } else { |
| token = Token::MUL; |
| } |
| break; |
| |
| case '%': |
| // % %= |
| token = Select('=', Token::ASSIGN_MOD, Token::MOD); |
| break; |
| |
| case '/': |
| // / // /* /= |
| Advance(); |
| if (c0_ == '/') { |
| Advance(); |
| if (c0_ == '#' || c0_ == '@') { |
| Advance(); |
| token = SkipSourceURLComment(); |
| } else { |
| PushBack(c0_); |
| token = SkipSingleLineComment(); |
| } |
| } else if (c0_ == '*') { |
| token = SkipMultiLineComment(); |
| } else if (c0_ == '=') { |
| token = Select(Token::ASSIGN_DIV); |
| } else { |
| token = Token::DIV; |
| } |
| break; |
| |
| case '&': |
| // & && &= |
| Advance(); |
| if (c0_ == '&') { |
| token = Select(Token::AND); |
| } else if (c0_ == '=') { |
| token = Select(Token::ASSIGN_BIT_AND); |
| } else { |
| token = Token::BIT_AND; |
| } |
| break; |
| |
| case '|': |
| // | || |= |
| Advance(); |
| if (c0_ == '|') { |
| token = Select(Token::OR); |
| } else if (c0_ == '=') { |
| token = Select(Token::ASSIGN_BIT_OR); |
| } else { |
| token = Token::BIT_OR; |
| } |
| break; |
| |
| case '^': |
| // ^ ^= |
| token = Select('=', Token::ASSIGN_BIT_XOR, Token::BIT_XOR); |
| break; |
| |
| case '.': |
| // . Number |
| Advance(); |
| if (IsDecimalDigit(c0_)) { |
| token = ScanNumber(true); |
| } else { |
| token = Token::PERIOD; |
| if (c0_ == '.') { |
| Advance(); |
| if (c0_ == '.') { |
| Advance(); |
| token = Token::ELLIPSIS; |
| } else { |
| PushBack('.'); |
| } |
| } |
| } |
| break; |
| |
| case ':': |
| token = Select(Token::COLON); |
| break; |
| |
| case ';': |
| token = Select(Token::SEMICOLON); |
| break; |
| |
| case ',': |
| token = Select(Token::COMMA); |
| break; |
| |
| case '(': |
| token = Select(Token::LPAREN); |
| break; |
| |
| case ')': |
| token = Select(Token::RPAREN); |
| break; |
| |
| case '[': |
| token = Select(Token::LBRACK); |
| break; |
| |
| case ']': |
| token = Select(Token::RBRACK); |
| break; |
| |
| case '{': |
| token = Select(Token::LBRACE); |
| break; |
| |
| case '}': |
| token = Select(Token::RBRACE); |
| break; |
| |
| case '?': |
| token = Select(Token::CONDITIONAL); |
| break; |
| |
| case '~': |
| token = Select(Token::BIT_NOT); |
| break; |
| |
| case '`': |
| token = ScanTemplateStart(); |
| break; |
| |
| case '#': |
| token = ScanPrivateName(); |
| break; |
| |
| default: |
| if (c0_ == kEndOfInput) { |
| token = Token::EOS; |
| } else if (unicode_cache_->IsIdentifierStart(c0_)) { |
| token = ScanIdentifierOrKeyword(); |
| } else if (IsDecimalDigit(c0_)) { |
| token = ScanNumber(false); |
| } else { |
| token = SkipWhiteSpace(); |
| if (token == Token::ILLEGAL) { |
| Advance(); |
| } |
| } |
| break; |
| } |
| |
| // Continue scanning for tokens as long as we're just skipping |
| // whitespace. |
| } while (token == Token::WHITESPACE); |
| |
| next_.location.end_pos = source_pos(); |
| if (Token::IsContextualKeyword(token)) { |
| next_.token = Token::IDENTIFIER; |
| next_.contextual_token = token; |
| } else { |
| next_.token = token; |
| next_.contextual_token = Token::UNINITIALIZED; |
| } |
| |
| #ifdef DEBUG |
| SanityCheckTokenDesc(current_); |
| SanityCheckTokenDesc(next_); |
| SanityCheckTokenDesc(next_next_); |
| #endif |
| } |
| |
| #ifdef DEBUG |
| void Scanner::SanityCheckTokenDesc(const TokenDesc& token) const { |
| // Most tokens should not have literal_chars or even raw_literal chars. |
| // The rules are: |
| // - UNINITIALIZED: we don't care. |
| // - TEMPLATE_*: need both literal + raw literal chars. |
| // - IDENTIFIERS, STRINGS, etc.: need a literal, but no raw literal. |
| // - all others: should have neither. |
| // Furthermore, only TEMPLATE_* tokens can have a |
| // invalid_template_escape_message. |
| |
| switch (token.token) { |
| case Token::UNINITIALIZED: |
| // token.literal_chars & other members might be garbage. That's ok. |
| break; |
| case Token::TEMPLATE_SPAN: |
| case Token::TEMPLATE_TAIL: |
| DCHECK_NOT_NULL(token.raw_literal_chars); |
| DCHECK_NOT_NULL(token.literal_chars); |
| break; |
| case Token::ESCAPED_KEYWORD: |
| case Token::ESCAPED_STRICT_RESERVED_WORD: |
| case Token::FUTURE_STRICT_RESERVED_WORD: |
| case Token::IDENTIFIER: |
| case Token::NUMBER: |
| case Token::BIGINT: |
| case Token::REGEXP_LITERAL: |
| case Token::SMI: |
| case Token::STRING: |
| case Token::PRIVATE_NAME: |
| DCHECK_NOT_NULL(token.literal_chars); |
| DCHECK_NULL(token.raw_literal_chars); |
| DCHECK_EQ(token.invalid_template_escape_message, MessageTemplate::kNone); |
| break; |
| default: |
| DCHECK_NULL(token.literal_chars); |
| DCHECK_NULL(token.raw_literal_chars); |
| DCHECK_EQ(token.invalid_template_escape_message, MessageTemplate::kNone); |
| break; |
| } |
| |
| DCHECK_IMPLIES(token.token != Token::IDENTIFIER, |
| token.contextual_token == Token::UNINITIALIZED); |
| DCHECK_IMPLIES(token.contextual_token != Token::UNINITIALIZED, |
| token.token == Token::IDENTIFIER && |
| Token::IsContextualKeyword(token.contextual_token)); |
| DCHECK(!Token::IsContextualKeyword(token.token)); |
| } |
| #endif // DEBUG |
| |
| void Scanner::SeekForward(int pos) { |
| // After this call, we will have the token at the given position as |
| // the "next" token. The "current" token will be invalid. |
| if (pos == next_.location.beg_pos) return; |
| int current_pos = source_pos(); |
| DCHECK_EQ(next_.location.end_pos, current_pos); |
| // Positions inside the lookahead token aren't supported. |
| DCHECK(pos >= current_pos); |
| if (pos != current_pos) { |
| source_->Seek(pos); |
| Advance(); |
| // This function is only called to seek to the location |
| // of the end of a function (at the "}" token). It doesn't matter |
| // whether there was a line terminator in the part we skip. |
| has_line_terminator_before_next_ = false; |
| has_multiline_comment_before_next_ = false; |
| } |
| Scan(); |
| } |
| |
| |
| template <bool capture_raw, bool in_template_literal> |
| bool Scanner::ScanEscape() { |
| uc32 c = c0_; |
| Advance<capture_raw>(); |
| |
| // Skip escaped newlines. |
| if (!in_template_literal && c0_ != kEndOfInput && |
| unibrow::IsLineTerminator(c)) { |
| // Allow escaped CR+LF newlines in multiline string literals. |
| if (IsCarriageReturn(c) && IsLineFeed(c0_)) Advance<capture_raw>(); |
| return true; |
| } |
| |
| switch (c) { |
| case '\'': // fall through |
| case '"' : // fall through |
| case '\\': break; |
| case 'b' : c = '\b'; break; |
| case 'f' : c = '\f'; break; |
| case 'n' : c = '\n'; break; |
| case 'r' : c = '\r'; break; |
| case 't' : c = '\t'; break; |
| case 'u' : { |
| c = ScanUnicodeEscape<capture_raw>(); |
| if (c < 0) return false; |
| break; |
| } |
| case 'v': |
| c = '\v'; |
| break; |
| case 'x': { |
| c = ScanHexNumber<capture_raw>(2); |
| if (c < 0) return false; |
| break; |
| } |
| case '0': // Fall through. |
| case '1': // fall through |
| case '2': // fall through |
| case '3': // fall through |
| case '4': // fall through |
| case '5': // fall through |
| case '6': // fall through |
| case '7': |
| c = ScanOctalEscape<capture_raw>(c, 2); |
| break; |
| } |
| |
| // Other escaped characters are interpreted as their non-escaped version. |
| AddLiteralChar(c); |
| return true; |
| } |
| |
| |
| template <bool capture_raw> |
| uc32 Scanner::ScanOctalEscape(uc32 c, int length) { |
| uc32 x = c - '0'; |
| int i = 0; |
| for (; i < length; i++) { |
| int d = c0_ - '0'; |
| if (d < 0 || d > 7) break; |
| int nx = x * 8 + d; |
| if (nx >= 256) break; |
| x = nx; |
| Advance<capture_raw>(); |
| } |
| // Anything except '\0' is an octal escape sequence, illegal in strict mode. |
| // Remember the position of octal escape sequences so that an error |
| // can be reported later (in strict mode). |
| // We don't report the error immediately, because the octal escape can |
| // occur before the "use strict" directive. |
| if (c != '0' || i > 0 || c0_ == '8' || c0_ == '9') { |
| octal_pos_ = Location(source_pos() - i - 1, source_pos() - 1); |
| octal_message_ = MessageTemplate::kStrictOctalEscape; |
| } |
| return x; |
| } |
| |
| |
| Token::Value Scanner::ScanString() { |
| uc32 quote = c0_; |
| Advance<false, false>(); // consume quote |
| |
| LiteralScope literal(this); |
| while (true) { |
| if (c0_ > kMaxAscii) { |
| HandleLeadSurrogate(); |
| break; |
| } |
| if (c0_ == kEndOfInput || c0_ == '\n' || c0_ == '\r') return Token::ILLEGAL; |
| if (c0_ == quote) { |
| literal.Complete(); |
| Advance<false, false>(); |
| return Token::STRING; |
| } |
| char c = static_cast<char>(c0_); |
| if (c == '\\') break; |
| Advance<false, false>(); |
| AddLiteralChar(c); |
| } |
| |
| while (c0_ != quote && c0_ != kEndOfInput && |
| !unibrow::IsLineTerminator(c0_)) { |
| uc32 c = c0_; |
| Advance(); |
| if (c == '\\') { |
| if (c0_ == kEndOfInput || !ScanEscape<false, false>()) { |
| return Token::ILLEGAL; |
| } |
| } else { |
| AddLiteralChar(c); |
| } |
| } |
| if (c0_ != quote) return Token::ILLEGAL; |
| literal.Complete(); |
| |
| Advance(); // consume quote |
| return Token::STRING; |
| } |
| |
| Token::Value Scanner::ScanPrivateName() { |
| if (!allow_harmony_private_fields()) { |
| ReportScannerError(source_pos(), |
| MessageTemplate::kInvalidOrUnexpectedToken); |
| return Token::ILLEGAL; |
| } |
| |
| LiteralScope literal(this); |
| DCHECK_EQ(c0_, '#'); |
| AddLiteralCharAdvance(); |
| if (c0_ == kEndOfInput || !unicode_cache_->IsIdentifierStart(c0_)) { |
| PushBack(c0_); |
| ReportScannerError(source_pos(), |
| MessageTemplate::kInvalidOrUnexpectedToken); |
| return Token::ILLEGAL; |
| } |
| |
| Token::Value token = ScanIdentifierOrKeywordInner(&literal); |
| return token == Token::ILLEGAL ? Token::ILLEGAL : Token::PRIVATE_NAME; |
| } |
| |
| Token::Value Scanner::ScanTemplateSpan() { |
| // When scanning a TemplateSpan, we are looking for the following construct: |
| // TEMPLATE_SPAN :: |
| // ` LiteralChars* ${ |
| // | } LiteralChars* ${ |
| // |
| // TEMPLATE_TAIL :: |
| // ` LiteralChars* ` |
| // | } LiteralChar* ` |
| // |
| // A TEMPLATE_SPAN should always be followed by an Expression, while a |
| // TEMPLATE_TAIL terminates a TemplateLiteral and does not need to be |
| // followed by an Expression. |
| |
| // These scoped helpers save and restore the original error state, so that we |
| // can specially treat invalid escape sequences in templates (which are |
| // handled by the parser). |
| ErrorState scanner_error_state(&scanner_error_, &scanner_error_location_); |
| ErrorState octal_error_state(&octal_message_, &octal_pos_); |
| |
| Token::Value result = Token::TEMPLATE_SPAN; |
| LiteralScope literal(this); |
| StartRawLiteral(); |
| const bool capture_raw = true; |
| const bool in_template_literal = true; |
| while (true) { |
| uc32 c = c0_; |
| Advance<capture_raw>(); |
| if (c == '`') { |
| result = Token::TEMPLATE_TAIL; |
| ReduceRawLiteralLength(1); |
| break; |
| } else if (c == '$' && c0_ == '{') { |
| Advance<capture_raw>(); // Consume '{' |
| ReduceRawLiteralLength(2); |
| break; |
| } else if (c == '\\') { |
| if (c0_ != kEndOfInput && unibrow::IsLineTerminator(c0_)) { |
| // The TV of LineContinuation :: \ LineTerminatorSequence is the empty |
| // code unit sequence. |
| uc32 lastChar = c0_; |
| Advance<capture_raw>(); |
| if (lastChar == '\r') { |
| ReduceRawLiteralLength(1); // Remove \r |
| if (c0_ == '\n') { |
| Advance<capture_raw>(); // Adds \n |
| } else { |
| AddRawLiteralChar('\n'); |
| } |
| } |
| } else { |
| bool success = ScanEscape<capture_raw, in_template_literal>(); |
| USE(success); |
| DCHECK_EQ(!success, has_error()); |
| // For templates, invalid escape sequence checking is handled in the |
| // parser. |
| scanner_error_state.MoveErrorTo(&next_); |
| octal_error_state.MoveErrorTo(&next_); |
| } |
| } else if (c < 0) { |
| // Unterminated template literal |
| PushBack(c); |
| break; |
| } else { |
| // The TRV of LineTerminatorSequence :: <CR> is the CV 0x000A. |
| // The TRV of LineTerminatorSequence :: <CR><LF> is the sequence |
| // consisting of the CV 0x000A. |
| if (c == '\r') { |
| ReduceRawLiteralLength(1); // Remove \r |
| if (c0_ == '\n') { |
| Advance<capture_raw>(); // Adds \n |
| } else { |
| AddRawLiteralChar('\n'); |
| } |
| c = '\n'; |
| } |
| AddLiteralChar(c); |
| } |
| } |
| literal.Complete(); |
| next_.location.end_pos = source_pos(); |
| next_.token = result; |
| next_.contextual_token = Token::UNINITIALIZED; |
| |
| return result; |
| } |
| |
| |
| Token::Value Scanner::ScanTemplateStart() { |
| DCHECK_EQ(next_next_.token, Token::UNINITIALIZED); |
| DCHECK_EQ(c0_, '`'); |
| next_.location.beg_pos = source_pos(); |
| Advance(); // Consume ` |
| return ScanTemplateSpan(); |
| } |
| |
| Handle<String> Scanner::SourceUrl(Isolate* isolate) const { |
| Handle<String> tmp; |
| if (source_url_.length() > 0) tmp = source_url_.Internalize(isolate); |
| return tmp; |
| } |
| |
| Handle<String> Scanner::SourceMappingUrl(Isolate* isolate) const { |
| Handle<String> tmp; |
| if (source_mapping_url_.length() > 0) |
| tmp = source_mapping_url_.Internalize(isolate); |
| return tmp; |
| } |
| |
| void Scanner::ScanDecimalDigits() { |
| while (IsDecimalDigit(c0_)) |
| AddLiteralCharAdvance(); |
| } |
| |
| |
| Token::Value Scanner::ScanNumber(bool seen_period) { |
| DCHECK(IsDecimalDigit(c0_)); // the first digit of the number or the fraction |
| |
| enum { |
| DECIMAL, |
| DECIMAL_WITH_LEADING_ZERO, |
| HEX, |
| OCTAL, |
| IMPLICIT_OCTAL, |
| BINARY |
| } kind = DECIMAL; |
| |
| LiteralScope literal(this); |
| bool at_start = !seen_period; |
| int start_pos = source_pos(); // For reporting octal positions. |
| if (seen_period) { |
| // we have already seen a decimal point of the float |
| AddLiteralChar('.'); |
| ScanDecimalDigits(); // we know we have at least one digit |
| |
| } else { |
| // if the first character is '0' we must check for octals and hex |
| if (c0_ == '0') { |
| AddLiteralCharAdvance(); |
| |
| // either 0, 0exxx, 0Exxx, 0.xxx, a hex number, a binary number or |
| // an octal number. |
| if (c0_ == 'x' || c0_ == 'X') { |
| // hex number |
| kind = HEX; |
| AddLiteralCharAdvance(); |
| if (!IsHexDigit(c0_)) { |
| // we must have at least one hex digit after 'x'/'X' |
| return Token::ILLEGAL; |
| } |
| while (IsHexDigit(c0_)) { |
| AddLiteralCharAdvance(); |
| } |
| } else if (c0_ == 'o' || c0_ == 'O') { |
| kind = OCTAL; |
| AddLiteralCharAdvance(); |
| if (!IsOctalDigit(c0_)) { |
| // we must have at least one octal digit after 'o'/'O' |
| return Token::ILLEGAL; |
| } |
| while (IsOctalDigit(c0_)) { |
| AddLiteralCharAdvance(); |
| } |
| } else if (c0_ == 'b' || c0_ == 'B') { |
| kind = BINARY; |
| AddLiteralCharAdvance(); |
| if (!IsBinaryDigit(c0_)) { |
| // we must have at least one binary digit after 'b'/'B' |
| return Token::ILLEGAL; |
| } |
| while (IsBinaryDigit(c0_)) { |
| AddLiteralCharAdvance(); |
| } |
| } else if ('0' <= c0_ && c0_ <= '7') { |
| // (possible) octal number |
| kind = IMPLICIT_OCTAL; |
| while (true) { |
| if (c0_ == '8' || c0_ == '9') { |
| at_start = false; |
| kind = DECIMAL_WITH_LEADING_ZERO; |
| break; |
| } |
| if (c0_ < '0' || '7' < c0_) { |
| // Octal literal finished. |
| octal_pos_ = Location(start_pos, source_pos()); |
| octal_message_ = MessageTemplate::kStrictOctalLiteral; |
| break; |
| } |
| AddLiteralCharAdvance(); |
| } |
| } else if (c0_ == '8' || c0_ == '9') { |
| kind = DECIMAL_WITH_LEADING_ZERO; |
| } |
| } |
| |
| // Parse decimal digits and allow trailing fractional part. |
| if (kind == DECIMAL || kind == DECIMAL_WITH_LEADING_ZERO) { |
| if (at_start) { |
| uint64_t value = 0; |
| while (IsDecimalDigit(c0_)) { |
| value = 10 * value + (c0_ - '0'); |
| |
| uc32 first_char = c0_; |
| Advance<false, false>(); |
| AddLiteralChar(first_char); |
| } |
| |
| if (next_.literal_chars->one_byte_literal().length() <= 10 && |
| value <= Smi::kMaxValue && c0_ != '.' && |
| (c0_ == kEndOfInput || !unicode_cache_->IsIdentifierStart(c0_))) { |
| next_.smi_value_ = static_cast<uint32_t>(value); |
| literal.Complete(); |
| HandleLeadSurrogate(); |
| |
| if (kind == DECIMAL_WITH_LEADING_ZERO) { |
| octal_pos_ = Location(start_pos, source_pos()); |
| octal_message_ = MessageTemplate::kStrictDecimalWithLeadingZero; |
| } |
| return Token::SMI; |
| } |
| HandleLeadSurrogate(); |
| } |
| |
| ScanDecimalDigits(); // optional |
| if (c0_ == '.') { |
| seen_period = true; |
| AddLiteralCharAdvance(); |
| ScanDecimalDigits(); // optional |
| } |
| } |
| } |
| |
| bool is_bigint = false; |
| if (allow_harmony_bigint() && c0_ == 'n' && !seen_period && |
| (kind == DECIMAL || kind == HEX || kind == OCTAL || kind == BINARY)) { |
| // Check that the literal is within our limits for BigInt length. |
| // For simplicity, use 4 bits per character to calculate the maximum |
| // allowed literal length. |
| static const int kMaxBigIntCharacters = BigInt::kMaxLengthBits / 4; |
| int length = source_pos() - start_pos - (kind != DECIMAL ? 2 : 0); |
| if (length > kMaxBigIntCharacters) { |
| ReportScannerError(Location(start_pos, source_pos()), |
| MessageTemplate::kBigIntTooBig); |
| return Token::ILLEGAL; |
| } |
| |
| is_bigint = true; |
| Advance(); |
| } else if (c0_ == 'e' || c0_ == 'E') { |
| // scan exponent, if any |
| DCHECK(kind != HEX); // 'e'/'E' must be scanned as part of the hex number |
| if (!(kind == DECIMAL || kind == DECIMAL_WITH_LEADING_ZERO)) |
| return Token::ILLEGAL; |
| // scan exponent |
| AddLiteralCharAdvance(); |
| if (c0_ == '+' || c0_ == '-') |
| AddLiteralCharAdvance(); |
| if (!IsDecimalDigit(c0_)) { |
| // we must have at least one decimal digit after 'e'/'E' |
| return Token::ILLEGAL; |
| } |
| ScanDecimalDigits(); |
| } |
| |
| // The source character immediately following a numeric literal must |
| // not be an identifier start or a decimal digit; see ECMA-262 |
| // section 7.8.3, page 17 (note that we read only one decimal digit |
| // if the value is 0). |
| if (IsDecimalDigit(c0_) || |
| (c0_ != kEndOfInput && unicode_cache_->IsIdentifierStart(c0_))) |
| return Token::ILLEGAL; |
| |
| literal.Complete(); |
| |
| if (kind == DECIMAL_WITH_LEADING_ZERO) { |
| octal_pos_ = Location(start_pos, source_pos()); |
| octal_message_ = MessageTemplate::kStrictDecimalWithLeadingZero; |
| } |
| |
| return is_bigint ? Token::BIGINT : Token::NUMBER; |
| } |
| |
| |
| uc32 Scanner::ScanIdentifierUnicodeEscape() { |
| Advance(); |
| if (c0_ != 'u') return -1; |
| Advance(); |
| return ScanUnicodeEscape<false>(); |
| } |
| |
| |
| template <bool capture_raw> |
| uc32 Scanner::ScanUnicodeEscape() { |
| // Accept both \uxxxx and \u{xxxxxx}. In the latter case, the number of |
| // hex digits between { } is arbitrary. \ and u have already been read. |
| if (c0_ == '{') { |
| int begin = source_pos() - 2; |
| Advance<capture_raw>(); |
| uc32 cp = ScanUnlimitedLengthHexNumber<capture_raw>(0x10FFFF, begin); |
| if (cp < 0 || c0_ != '}') { |
| ReportScannerError(source_pos(), |
| MessageTemplate::kInvalidUnicodeEscapeSequence); |
| return -1; |
| } |
| Advance<capture_raw>(); |
| return cp; |
| } |
| const bool unicode = true; |
| return ScanHexNumber<capture_raw, unicode>(4); |
| } |
| |
| |
| // ---------------------------------------------------------------------------- |
| // Keyword Matcher |
| |
| #define KEYWORDS(KEYWORD_GROUP, KEYWORD) \ |
| KEYWORD_GROUP('a') \ |
| KEYWORD("arguments", Token::ARGUMENTS) \ |
| KEYWORD("as", Token::AS) \ |
| KEYWORD("async", Token::ASYNC) \ |
| KEYWORD("await", Token::AWAIT) \ |
| KEYWORD("anonymous", Token::ANONYMOUS) \ |
| KEYWORD_GROUP('b') \ |
| KEYWORD("break", Token::BREAK) \ |
| KEYWORD_GROUP('c') \ |
| KEYWORD("case", Token::CASE) \ |
| KEYWORD("catch", Token::CATCH) \ |
| KEYWORD("class", Token::CLASS) \ |
| KEYWORD("const", Token::CONST) \ |
| KEYWORD("constructor", Token::CONSTRUCTOR) \ |
| KEYWORD("continue", Token::CONTINUE) \ |
| KEYWORD_GROUP('d') \ |
| KEYWORD("debugger", Token::DEBUGGER) \ |
| KEYWORD("default", Token::DEFAULT) \ |
| KEYWORD("delete", Token::DELETE) \ |
| KEYWORD("do", Token::DO) \ |
| KEYWORD_GROUP('e') \ |
| KEYWORD("else", Token::ELSE) \ |
| KEYWORD("enum", Token::ENUM) \ |
| KEYWORD("eval", Token::EVAL) \ |
| KEYWORD("export", Token::EXPORT) \ |
| KEYWORD("extends", Token::EXTENDS) \ |
| KEYWORD_GROUP('f') \ |
| KEYWORD("false", Token::FALSE_LITERAL) \ |
| KEYWORD("finally", Token::FINALLY) \ |
| KEYWORD("for", Token::FOR) \ |
| KEYWORD("from", Token::FROM) \ |
| KEYWORD("function", Token::FUNCTION) \ |
| KEYWORD_GROUP('g') \ |
| KEYWORD("get", Token::GET) \ |
| KEYWORD_GROUP('i') \ |
| KEYWORD("if", Token::IF) \ |
| KEYWORD("implements", Token::FUTURE_STRICT_RESERVED_WORD) \ |
| KEYWORD("import", Token::IMPORT) \ |
| KEYWORD("in", Token::IN) \ |
| KEYWORD("instanceof", Token::INSTANCEOF) \ |
| KEYWORD("interface", Token::FUTURE_STRICT_RESERVED_WORD) \ |
| KEYWORD_GROUP('l') \ |
| KEYWORD("let", Token::LET) \ |
| KEYWORD_GROUP('m') \ |
| KEYWORD("meta", Token::META) \ |
| KEYWORD_GROUP('n') \ |
| KEYWORD("name", Token::NAME) \ |
| KEYWORD("new", Token::NEW) \ |
| KEYWORD("null", Token::NULL_LITERAL) \ |
| KEYWORD_GROUP('o') \ |
| KEYWORD("of", Token::OF) \ |
| KEYWORD_GROUP('p') \ |
| KEYWORD("package", Token::FUTURE_STRICT_RESERVED_WORD) \ |
| KEYWORD("private", Token::FUTURE_STRICT_RESERVED_WORD) \ |
| KEYWORD("protected", Token::FUTURE_STRICT_RESERVED_WORD) \ |
| KEYWORD("prototype", Token::PROTOTYPE) \ |
| KEYWORD("public", Token::FUTURE_STRICT_RESERVED_WORD) \ |
| KEYWORD_GROUP('r') \ |
| KEYWORD("return", Token::RETURN) \ |
| KEYWORD_GROUP('s') \ |
| KEYWORD("sent", Token::SENT) \ |
| KEYWORD("set", Token::SET) \ |
| KEYWORD("static", Token::STATIC) \ |
| KEYWORD("super", Token::SUPER) \ |
| KEYWORD("switch", Token::SWITCH) \ |
| KEYWORD_GROUP('t') \ |
| KEYWORD("target", Token::TARGET) \ |
| KEYWORD("this", Token::THIS) \ |
| KEYWORD("throw", Token::THROW) \ |
| KEYWORD("true", Token::TRUE_LITERAL) \ |
| KEYWORD("try", Token::TRY) \ |
| KEYWORD("typeof", Token::TYPEOF) \ |
| KEYWORD_GROUP('u') \ |
| KEYWORD("undefined", Token::UNDEFINED) \ |
| KEYWORD_GROUP('v') \ |
| KEYWORD("var", Token::VAR) \ |
| KEYWORD("void", Token::VOID) \ |
| KEYWORD_GROUP('w') \ |
| KEYWORD("while", Token::WHILE) \ |
| KEYWORD("with", Token::WITH) \ |
| KEYWORD_GROUP('y') \ |
| KEYWORD("yield", Token::YIELD) \ |
| KEYWORD_GROUP('_') \ |
| KEYWORD("__proto__", Token::PROTO_UNDERSCORED) |
| |
| static Token::Value KeywordOrIdentifierToken(const uint8_t* input, |
| int input_length) { |
| DCHECK_GE(input_length, 1); |
| const int kMinLength = 2; |
| const int kMaxLength = 11; |
| if (input_length < kMinLength || input_length > kMaxLength) { |
| return Token::IDENTIFIER; |
| } |
| switch (input[0]) { |
| default: |
| #define KEYWORD_GROUP_CASE(ch) \ |
| break; \ |
| case ch: |
| #define KEYWORD(keyword, token) \ |
| { \ |
| /* 'keyword' is a char array, so sizeof(keyword) is */ \ |
| /* strlen(keyword) plus 1 for the NUL char. */ \ |
| const int keyword_length = sizeof(keyword) - 1; \ |
| STATIC_ASSERT(keyword_length >= kMinLength); \ |
| STATIC_ASSERT(keyword_length <= kMaxLength); \ |
| DCHECK_EQ(input[0], keyword[0]); \ |
| DCHECK(token == Token::FUTURE_STRICT_RESERVED_WORD || \ |
| 0 == strncmp(keyword, Token::String(token), sizeof(keyword))); \ |
| if (input_length == keyword_length && input[1] == keyword[1] && \ |
| (keyword_length <= 2 || input[2] == keyword[2]) && \ |
| (keyword_length <= 3 || input[3] == keyword[3]) && \ |
| (keyword_length <= 4 || input[4] == keyword[4]) && \ |
| (keyword_length <= 5 || input[5] == keyword[5]) && \ |
| (keyword_length <= 6 || input[6] == keyword[6]) && \ |
| (keyword_length <= 7 || input[7] == keyword[7]) && \ |
| (keyword_length <= 8 || input[8] == keyword[8]) && \ |
| (keyword_length <= 9 || input[9] == keyword[9]) && \ |
| (keyword_length <= 10 || input[10] == keyword[10])) { \ |
| return token; \ |
| } \ |
| } |
| KEYWORDS(KEYWORD_GROUP_CASE, KEYWORD) |
| } |
| return Token::IDENTIFIER; |
| } |
| |
| Token::Value Scanner::ScanIdentifierOrKeyword() { |
| LiteralScope literal(this); |
| return ScanIdentifierOrKeywordInner(&literal); |
| } |
| |
| Token::Value Scanner::ScanIdentifierOrKeywordInner(LiteralScope* literal) { |
| DCHECK(unicode_cache_->IsIdentifierStart(c0_)); |
| if (IsInRange(c0_, 'a', 'z') || c0_ == '_') { |
| do { |
| char first_char = static_cast<char>(c0_); |
| Advance<false, false>(); |
| AddLiteralChar(first_char); |
| } while (IsInRange(c0_, 'a', 'z') || c0_ == '_'); |
| |
| if (IsDecimalDigit(c0_) || IsInRange(c0_, 'A', 'Z') || c0_ == '_' || |
| c0_ == '$') { |
| // Identifier starting with lowercase. |
| char first_char = static_cast<char>(c0_); |
| Advance<false, false>(); |
| AddLiteralChar(first_char); |
| while (IsAsciiIdentifier(c0_)) { |
| char first_char = static_cast<char>(c0_); |
| Advance<false, false>(); |
| AddLiteralChar(first_char); |
| } |
| if (c0_ <= kMaxAscii && c0_ != '\\') { |
| literal->Complete(); |
| return Token::IDENTIFIER; |
| } |
| } else if (c0_ <= kMaxAscii && c0_ != '\\') { |
| // Only a-z+ or _: could be a keyword or identifier. |
| Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal(); |
| Token::Value token = |
| KeywordOrIdentifierToken(chars.start(), chars.length()); |
| if (token == Token::IDENTIFIER || |
| token == Token::FUTURE_STRICT_RESERVED_WORD || |
| Token::IsContextualKeyword(token)) |
| literal->Complete(); |
| return token; |
| } |
| |
| HandleLeadSurrogate(); |
| } else if (IsInRange(c0_, 'A', 'Z') || c0_ == '_' || c0_ == '$') { |
| do { |
| char first_char = static_cast<char>(c0_); |
| Advance<false, false>(); |
| AddLiteralChar(first_char); |
| } while (IsAsciiIdentifier(c0_)); |
| |
| if (c0_ <= kMaxAscii && c0_ != '\\') { |
| literal->Complete(); |
| return Token::IDENTIFIER; |
| } |
| |
| HandleLeadSurrogate(); |
| } else if (c0_ == '\\') { |
| // Scan identifier start character. |
| uc32 c = ScanIdentifierUnicodeEscape(); |
| // Only allow legal identifier start characters. |
| if (c < 0 || |
| c == '\\' || // No recursive escapes. |
| !unicode_cache_->IsIdentifierStart(c)) { |
| return Token::ILLEGAL; |
| } |
| AddLiteralChar(c); |
| return ScanIdentifierSuffix(literal, true); |
| } else { |
| uc32 first_char = c0_; |
| Advance(); |
| AddLiteralChar(first_char); |
| } |
| |
| // Scan the rest of the identifier characters. |
| while (c0_ != kEndOfInput && unicode_cache_->IsIdentifierPart(c0_)) { |
| if (c0_ != '\\') { |
| uc32 next_char = c0_; |
| Advance(); |
| AddLiteralChar(next_char); |
| continue; |
| } |
| // Fallthrough if no longer able to complete keyword. |
| return ScanIdentifierSuffix(literal, false); |
| } |
| |
| if (next_.literal_chars->is_one_byte()) { |
| Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal(); |
| Token::Value token = |
| KeywordOrIdentifierToken(chars.start(), chars.length()); |
| if (token == Token::IDENTIFIER || |
| token == Token::FUTURE_STRICT_RESERVED_WORD || |
| Token::IsContextualKeyword(token)) |
| literal->Complete(); |
| return token; |
| } |
| literal->Complete(); |
| return Token::IDENTIFIER; |
| } |
| |
| |
| Token::Value Scanner::ScanIdentifierSuffix(LiteralScope* literal, |
| bool escaped) { |
| // Scan the rest of the identifier characters. |
| while (c0_ != kEndOfInput && unicode_cache_->IsIdentifierPart(c0_)) { |
| if (c0_ == '\\') { |
| uc32 c = ScanIdentifierUnicodeEscape(); |
| escaped = true; |
| // Only allow legal identifier part characters. |
| if (c < 0 || |
| c == '\\' || |
| !unicode_cache_->IsIdentifierPart(c)) { |
| return Token::ILLEGAL; |
| } |
| AddLiteralChar(c); |
| } else { |
| AddLiteralChar(c0_); |
| Advance(); |
| } |
| } |
| literal->Complete(); |
| |
| if (escaped && next_.literal_chars->is_one_byte()) { |
| Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal(); |
| Token::Value token = |
| KeywordOrIdentifierToken(chars.start(), chars.length()); |
| /* TODO(adamk): YIELD should be handled specially. */ |
| if (token == Token::IDENTIFIER || Token::IsContextualKeyword(token)) { |
| return token; |
| } else if (token == Token::FUTURE_STRICT_RESERVED_WORD || |
| token == Token::LET || token == Token::STATIC) { |
| return Token::ESCAPED_STRICT_RESERVED_WORD; |
| } else { |
| return Token::ESCAPED_KEYWORD; |
| } |
| } |
| return Token::IDENTIFIER; |
| } |
| |
| bool Scanner::ScanRegExpPattern() { |
| DCHECK(next_next_.token == Token::UNINITIALIZED); |
| DCHECK(next_.token == Token::DIV || next_.token == Token::ASSIGN_DIV); |
| |
| // Scan: ('/' | '/=') RegularExpressionBody '/' RegularExpressionFlags |
| bool in_character_class = false; |
| bool seen_equal = (next_.token == Token::ASSIGN_DIV); |
| |
| // Previous token is either '/' or '/=', in the second case, the |
| // pattern starts at =. |
| next_.location.beg_pos = source_pos() - (seen_equal ? 2 : 1); |
| next_.location.end_pos = source_pos() - (seen_equal ? 1 : 0); |
| |
| // Scan regular expression body: According to ECMA-262, 3rd, 7.8.5, |
| // the scanner should pass uninterpreted bodies to the RegExp |
| // constructor. |
| LiteralScope literal(this); |
| if (seen_equal) { |
| AddLiteralChar('='); |
| } |
| |
| while (c0_ != '/' || in_character_class) { |
| if (c0_ == kEndOfInput || unibrow::IsLineTerminator(c0_)) { |
| return false; |
| } |
| if (c0_ == '\\') { // Escape sequence. |
| AddLiteralCharAdvance(); |
| if (c0_ == kEndOfInput || unibrow::IsLineTerminator(c0_)) { |
| return false; |
| } |
| AddLiteralCharAdvance(); |
| // If the escape allows more characters, i.e., \x??, \u????, or \c?, |
| // only "safe" characters are allowed (letters, digits, underscore), |
| // otherwise the escape isn't valid and the invalid character has |
| // its normal meaning. I.e., we can just continue scanning without |
| // worrying whether the following characters are part of the escape |
| // or not, since any '/', '\\' or '[' is guaranteed to not be part |
| // of the escape sequence. |
| |
| // TODO(896): At some point, parse RegExps more thoroughly to capture |
| // octal esacpes in strict mode. |
| } else { // Unescaped character. |
| if (c0_ == '[') in_character_class = true; |
| if (c0_ == ']') in_character_class = false; |
| AddLiteralCharAdvance(); |
| } |
| } |
| Advance(); // consume '/' |
| |
| literal.Complete(); |
| next_.token = Token::REGEXP_LITERAL; |
| next_.contextual_token = Token::UNINITIALIZED; |
| return true; |
| } |
| |
| |
| Maybe<RegExp::Flags> Scanner::ScanRegExpFlags() { |
| DCHECK(next_.token == Token::REGEXP_LITERAL); |
| |
| // Scan regular expression flags. |
| int flags = 0; |
| while (c0_ != kEndOfInput && unicode_cache_->IsIdentifierPart(c0_)) { |
| RegExp::Flags flag = RegExp::kNone; |
| switch (c0_) { |
| case 'g': |
| flag = RegExp::kGlobal; |
| break; |
| case 'i': |
| flag = RegExp::kIgnoreCase; |
| break; |
| case 'm': |
| flag = RegExp::kMultiline; |
| break; |
| case 's': |
| flag = RegExp::kDotAll; |
| break; |
| case 'u': |
| flag = RegExp::kUnicode; |
| break; |
| case 'y': |
| flag = RegExp::kSticky; |
| break; |
| default: |
| return Nothing<RegExp::Flags>(); |
| } |
| if (flags & flag) { |
| return Nothing<RegExp::Flags>(); |
| } |
| Advance(); |
| flags |= flag; |
| } |
| |
| next_.location.end_pos = source_pos(); |
| return Just(RegExp::Flags(flags)); |
| } |
| |
| const AstRawString* Scanner::CurrentSymbol( |
| AstValueFactory* ast_value_factory) const { |
| if (is_literal_one_byte()) { |
| return ast_value_factory->GetOneByteString(literal_one_byte_string()); |
| } |
| return ast_value_factory->GetTwoByteString(literal_two_byte_string()); |
| } |
| |
| const AstRawString* Scanner::NextSymbol( |
| AstValueFactory* ast_value_factory) const { |
| if (is_next_literal_one_byte()) { |
| return ast_value_factory->GetOneByteString(next_literal_one_byte_string()); |
| } |
| return ast_value_factory->GetTwoByteString(next_literal_two_byte_string()); |
| } |
| |
| const AstRawString* Scanner::CurrentRawSymbol( |
| AstValueFactory* ast_value_factory) const { |
| if (is_raw_literal_one_byte()) { |
| return ast_value_factory->GetOneByteString(raw_literal_one_byte_string()); |
| } |
| return ast_value_factory->GetTwoByteString(raw_literal_two_byte_string()); |
| } |
| |
| |
| double Scanner::DoubleValue() { |
| DCHECK(is_literal_one_byte()); |
| return StringToDouble( |
| unicode_cache_, |
| literal_one_byte_string(), |
| ALLOW_HEX | ALLOW_OCTAL | ALLOW_IMPLICIT_OCTAL | ALLOW_BINARY); |
| } |
| |
| const char* Scanner::CurrentLiteralAsCString(Zone* zone) const { |
| DCHECK(is_literal_one_byte()); |
| Vector<const uint8_t> vector = literal_one_byte_string(); |
| int length = vector.length(); |
| char* buffer = zone->NewArray<char>(length + 1); |
| memcpy(buffer, vector.start(), length); |
| buffer[length] = '\0'; |
| return buffer; |
| } |
| |
| bool Scanner::IsDuplicateSymbol(DuplicateFinder* duplicate_finder, |
| AstValueFactory* ast_value_factory) const { |
| DCHECK_NOT_NULL(duplicate_finder); |
| DCHECK_NOT_NULL(ast_value_factory); |
| const AstRawString* string = CurrentSymbol(ast_value_factory); |
| return !duplicate_finder->known_symbols_.insert(string).second; |
| } |
| |
| void Scanner::SeekNext(size_t position) { |
| // Use with care: This cleanly resets most, but not all scanner state. |
| // TODO(vogelheim): Fix this, or at least DCHECK the relevant conditions. |
| |
| // To re-scan from a given character position, we need to: |
| // 1, Reset the current_, next_ and next_next_ tokens |
| // (next_ + next_next_ will be overwrittem by Next(), |
| // current_ will remain unchanged, so overwrite it fully.) |
| current_ = {{0, 0}, |
| nullptr, |
| nullptr, |
| 0, |
| Token::UNINITIALIZED, |
| MessageTemplate::kNone, |
| {0, 0}, |
| Token::UNINITIALIZED}; |
| next_.token = Token::UNINITIALIZED; |
| next_.contextual_token = Token::UNINITIALIZED; |
| next_next_.token = Token::UNINITIALIZED; |
| next_next_.contextual_token = Token::UNINITIALIZED; |
| // 2, reset the source to the desired position, |
| source_->Seek(position); |
| // 3, re-scan, by scanning the look-ahead char + 1 token (next_). |
| c0_ = source_->Advance(); |
| Next(); |
| DCHECK_EQ(next_.location.beg_pos, static_cast<int>(position)); |
| } |
| |
| } // namespace internal |
| } // namespace v8 |
