Upgrade V8 to version 4.9.385.28
https://chromium.googlesource.com/v8/v8/+/4.9.385.28
FPIIM-449
Change-Id: I4b2e74289d4bf3667f2f3dc8aa2e541f63e26eb4
diff --git a/src/parsing/scanner.cc b/src/parsing/scanner.cc
new file mode 100644
index 0000000..7317593
--- /dev/null
+++ b/src/parsing/scanner.cc
@@ -0,0 +1,1673 @@
+// 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/list-inl.h"
+#include "src/parsing/parser.h"
+
+namespace v8 {
+namespace internal {
+
+
+Handle<String> LiteralBuffer::Internalize(Isolate* isolate) const {
+ if (is_one_byte()) {
+ return isolate->factory()->InternalizeOneByteString(one_byte_literal());
+ }
+ return isolate->factory()->InternalizeTwoByteString(two_byte_literal());
+}
+
+
+// Default implementation for streams that do not support bookmarks.
+bool Utf16CharacterStream::SetBookmark() { return false; }
+void Utf16CharacterStream::ResetToBookmark() { UNREACHABLE(); }
+
+
+// ----------------------------------------------------------------------------
+// Scanner
+
+Scanner::Scanner(UnicodeCache* unicode_cache)
+ : unicode_cache_(unicode_cache),
+ bookmark_c0_(kNoBookmark),
+ octal_pos_(Location::invalid()) {
+ bookmark_current_.literal_chars = &bookmark_current_literal_;
+ bookmark_current_.raw_literal_chars = &bookmark_current_raw_literal_;
+ bookmark_next_.literal_chars = &bookmark_next_literal_;
+ bookmark_next_.raw_literal_chars = &bookmark_next_raw_literal_;
+}
+
+
+void Scanner::Initialize(Utf16CharacterStream* source) {
+ source_ = source;
+ // Need to capture identifiers in order to recognize "get" and "set"
+ // in object literals.
+ Init();
+ // Skip initial whitespace allowing HTML comment ends just like
+ // after a newline and scan first token.
+ has_line_terminator_before_next_ = true;
+ SkipWhiteSpace();
+ Scan();
+}
+
+
+template <bool capture_raw>
+uc32 Scanner::ScanHexNumber(int expected_length) {
+ DCHECK(expected_length <= 4); // prevent overflow
+
+ uc32 x = 0;
+ for (int i = 0; i < expected_length; i++) {
+ int d = HexValue(c0_);
+ if (d < 0) {
+ return -1;
+ }
+ x = x * 16 + d;
+ Advance<capture_raw>();
+ }
+
+ return x;
+}
+
+
+template <bool capture_raw>
+uc32 Scanner::ScanUnlimitedLengthHexNumber(int max_value) {
+ uc32 x = 0;
+ int d = HexValue(c0_);
+ if (d < 0) {
+ return -1;
+ }
+ while (d >= 0) {
+ x = x * 16 + d;
+ if (x > max_value) 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).
+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
+};
+
+
+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;
+ 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_.location.beg_pos = pos;
+ next_.location.end_pos = pos + 1;
+ Advance();
+ return current_.token;
+ }
+ }
+ Scan();
+ return current_.token;
+}
+
+
+Token::Value Scanner::PeekAhead() {
+ if (next_next_.token != Token::UNINITIALIZED) {
+ return next_next_.token;
+ }
+ TokenDesc prev = current_;
+ Next();
+ Token::Value ret = next_.token;
+ next_next_ = next_;
+ next_ = current_;
+ current_ = prev;
+ return ret;
+}
+
+
+// TODO(yangguo): check whether this is actually necessary.
+static inline bool IsLittleEndianByteOrderMark(uc32 c) {
+ // The Unicode value U+FFFE is guaranteed never to be assigned as a
+ // Unicode character; this implies that in a Unicode context the
+ // 0xFF, 0xFE byte pattern can only be interpreted as the U+FEFF
+ // character expressed in little-endian byte order (since it could
+ // not be a U+FFFE character expressed in big-endian byte
+ // order). Nevertheless, we check for it to be compatible with
+ // Spidermonkey.
+ return c == 0xFFFE;
+}
+
+
+bool Scanner::SkipWhiteSpace() {
+ int start_position = source_pos();
+
+ while (true) {
+ while (true) {
+ // The unicode cache accepts unsigned inputs.
+ if (c0_ < 0) break;
+ // Advance as long as character is a WhiteSpace or LineTerminator.
+ // Remember if the latter is the case.
+ if (unicode_cache_->IsLineTerminator(c0_)) {
+ has_line_terminator_before_next_ = true;
+ } else if (!unicode_cache_->IsWhiteSpace(c0_) &&
+ !IsLittleEndianByteOrderMark(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_) {
+ Advance();
+ if (c0_ == '-') {
+ Advance();
+ if (c0_ == '>') {
+ // Treat the rest of the line as a comment.
+ SkipSingleLineComment();
+ // Continue skipping white space after the comment.
+ continue;
+ }
+ PushBack('-'); // undo Advance()
+ }
+ PushBack('-'); // undo Advance()
+ }
+ // Return whether or not we skipped any characters.
+ return source_pos() != start_position;
+ }
+}
+
+
+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_ >= 0 && !unicode_cache_->IsLineTerminator(c0_)) {
+ Advance();
+ }
+
+ return Token::WHITESPACE;
+}
+
+
+Token::Value Scanner::SkipSourceURLComment() {
+ TryToParseSourceURLComment();
+ while (c0_ >= 0 && !unicode_cache_->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_ < 0 || !unicode_cache_->IsWhiteSpace(c0_)) return;
+ Advance();
+ LiteralBuffer name;
+ while (c0_ >= 0 && !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_ >= 0 && unicode_cache_->IsWhiteSpace(c0_)) {
+ Advance();
+ }
+ while (c0_ >= 0 && !unicode_cache_->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_ >= 0 && !unicode_cache_->IsLineTerminator(c0_)) {
+ if (!unicode_cache_->IsWhiteSpace(c0_)) {
+ value->Reset();
+ break;
+ }
+ Advance();
+ }
+}
+
+
+Token::Value Scanner::SkipMultiLineComment() {
+ DCHECK(c0_ == '*');
+ Advance();
+
+ while (c0_ >= 0) {
+ uc32 ch = c0_;
+ Advance();
+ if (c0_ >= 0 && unicode_cache_->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(c0_ == '!');
+ Advance();
+ if (c0_ == '-') {
+ Advance();
+ if (c0_ == '-') return SkipSingleLineComment();
+ PushBack('-'); // undo Advance()
+ }
+ PushBack('!'); // undo Advance()
+ DCHECK(c0_ == '!');
+ return Token::LT;
+}
+
+
+void Scanner::Scan() {
+ next_.literal_chars = NULL;
+ next_.raw_literal_chars = NULL;
+ 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_ == '>' && has_line_terminator_before_next_) {
+ // For compatibility with SpiderMonkey, we skip lines that
+ // start with an HTML comment end '-->'.
+ token = SkipSingleLineComment();
+ } else {
+ token = Token::DEC;
+ }
+ } else if (c0_ == '=') {
+ token = Select(Token::ASSIGN_SUB);
+ } else {
+ token = Token::SUB;
+ }
+ break;
+
+ case '*':
+ // * *=
+ token = Select('=', Token::ASSIGN_MUL, 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;
+
+ default:
+ if (c0_ < 0) {
+ token = Token::EOS;
+ } else if (unicode_cache_->IsIdentifierStart(c0_)) {
+ token = ScanIdentifierOrKeyword();
+ } else if (IsDecimalDigit(c0_)) {
+ token = ScanNumber(false);
+ } else if (SkipWhiteSpace()) {
+ token = Token::WHITESPACE;
+ } else {
+ token = Select(Token::ILLEGAL);
+ }
+ break;
+ }
+
+ // Continue scanning for tokens as long as we're just skipping
+ // whitespace.
+ } while (token == Token::WHITESPACE);
+
+ next_.location.end_pos = source_pos();
+ next_.token = token;
+}
+
+
+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_->SeekForward(pos - source_->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_ >= 0 && unicode_cache_->IsLineTerminator(c)) {
+ // Allow CR+LF newlines in multiline string literals.
+ if (IsCarriageReturn(c) && IsLineFeed(c0_)) Advance<capture_raw>();
+ // Allow LF+CR newlines in multiline string literals.
+ if (IsLineFeed(c) && IsCarriageReturn(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;
+ }
+
+ // According to ECMA-262, section 7.8.4, characters not covered by the
+ // above cases should be illegal, but they are commonly handled as
+ // non-escaped characters by JS VMs.
+ AddLiteralChar(c);
+ return true;
+}
+
+
+// Octal escapes of the forms '\0xx' and '\xxx' are not a part of
+// ECMA-262. Other JS VMs support them.
+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) {
+ octal_pos_ = Location(source_pos() - i - 1, source_pos() - 1);
+ }
+ return x;
+}
+
+
+const int kMaxAscii = 127;
+
+
+Token::Value Scanner::ScanString() {
+ uc32 quote = c0_;
+ Advance<false, false>(); // consume quote
+
+ LiteralScope literal(this);
+ while (true) {
+ if (c0_ > kMaxAscii) {
+ HandleLeadSurrogate();
+ break;
+ }
+ if (c0_ < 0 || c0_ == '\n' || c0_ == '\r') return Token::ILLEGAL;
+ if (c0_ == quote) {
+ literal.Complete();
+ Advance<false, false>();
+ return Token::STRING;
+ }
+ uc32 c = c0_;
+ if (c == '\\') break;
+ Advance<false, false>();
+ AddLiteralChar(c);
+ }
+
+ while (c0_ != quote && c0_ >= 0
+ && !unicode_cache_->IsLineTerminator(c0_)) {
+ uc32 c = c0_;
+ Advance();
+ if (c == '\\') {
+ if (c0_ < 0 || !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::ScanTemplateSpan() {
+ // When scanning a TemplateSpan, we are looking for the following construct:
+ // TEMPLATE_SPAN ::
+ // ` LiteralChars* ${
+ // | } LiteralChars* ${
+ //
+ // TEMPLATE_TAIL ::
+ // ` LiteralChars* `
+ // | } LiteralChar* `
+ //
+ // A TEMPLATE_SPAN should always be followed by an Expression, while a
+ // TEMPLATE_TAIL terminates a TemplateLiteral and does not need to be
+ // followed by an Expression.
+
+ Token::Value result = Token::TEMPLATE_SPAN;
+ LiteralScope literal(this);
+ StartRawLiteral();
+ const bool capture_raw = true;
+ const bool in_template_literal = true;
+
+ while (true) {
+ uc32 c = c0_;
+ Advance<capture_raw>();
+ if (c == '`') {
+ result = Token::TEMPLATE_TAIL;
+ ReduceRawLiteralLength(1);
+ break;
+ } else if (c == '$' && c0_ == '{') {
+ Advance<capture_raw>(); // Consume '{'
+ ReduceRawLiteralLength(2);
+ break;
+ } else if (c == '\\') {
+ if (c0_ > 0 && unicode_cache_->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 if (!ScanEscape<capture_raw, in_template_literal>()) {
+ return Token::ILLEGAL;
+ }
+ } 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;
+ return result;
+}
+
+
+Token::Value Scanner::ScanTemplateStart() {
+ DCHECK(c0_ == '`');
+ next_.location.beg_pos = source_pos();
+ Advance(); // Consume `
+ return ScanTemplateSpan();
+}
+
+
+Token::Value Scanner::ScanTemplateContinuation() {
+ DCHECK_EQ(next_.token, Token::RBRACE);
+ next_.location.beg_pos = source_pos() - 1; // We already consumed }
+ return ScanTemplateSpan();
+}
+
+
+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, HEX, OCTAL, IMPLICIT_OCTAL, BINARY } kind = DECIMAL;
+
+ LiteralScope literal(this);
+ bool at_start = !seen_period;
+ 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') {
+ int start_pos = source_pos(); // For reporting octal positions.
+ 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;
+ break;
+ }
+ if (c0_ < '0' || '7' < c0_) {
+ // Octal literal finished.
+ octal_pos_ = Location(start_pos, source_pos());
+ break;
+ }
+ AddLiteralCharAdvance();
+ }
+ }
+ }
+
+ // Parse decimal digits and allow trailing fractional part.
+ if (kind == DECIMAL) {
+ 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_ != 'e' && c0_ != 'E') {
+ next_.smi_value_ = static_cast<int>(value);
+ literal.Complete();
+ HandleLeadSurrogate();
+
+ return Token::SMI;
+ }
+ HandleLeadSurrogate();
+ }
+
+ ScanDecimalDigits(); // optional
+ if (c0_ == '.') {
+ AddLiteralCharAdvance();
+ ScanDecimalDigits(); // optional
+ }
+ }
+ }
+
+ // scan exponent, if any
+ if (c0_ == 'e' || c0_ == 'E') {
+ DCHECK(kind != HEX); // 'e'/'E' must be scanned as part of the hex number
+ if (kind != DECIMAL) 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_ >= 0 && unicode_cache_->IsIdentifierStart(c0_)))
+ return Token::ILLEGAL;
+
+ literal.Complete();
+
+ return 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_ == '{') {
+ Advance<capture_raw>();
+ uc32 cp = ScanUnlimitedLengthHexNumber<capture_raw>(0x10ffff);
+ if (cp < 0) {
+ return -1;
+ }
+ if (c0_ != '}') {
+ return -1;
+ }
+ Advance<capture_raw>();
+ return cp;
+ }
+ return ScanHexNumber<capture_raw>(4);
+}
+
+
+// ----------------------------------------------------------------------------
+// Keyword Matcher
+
+#define KEYWORDS(KEYWORD_GROUP, KEYWORD) \
+ 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("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::FUTURE_RESERVED_WORD) \
+ 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("function", Token::FUNCTION) \
+ 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('n') \
+ KEYWORD("new", Token::NEW) \
+ KEYWORD("null", Token::NULL_LITERAL) \
+ 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("public", Token::FUTURE_STRICT_RESERVED_WORD) \
+ KEYWORD_GROUP('r') \
+ KEYWORD("return", Token::RETURN) \
+ KEYWORD_GROUP('s') \
+ KEYWORD("static", Token::STATIC) \
+ KEYWORD("super", Token::SUPER) \
+ KEYWORD("switch", Token::SWITCH) \
+ KEYWORD_GROUP('t') \
+ KEYWORD("this", Token::THIS) \
+ KEYWORD("throw", Token::THROW) \
+ KEYWORD("true", Token::TRUE_LITERAL) \
+ KEYWORD("try", Token::TRY) \
+ KEYWORD("typeof", Token::TYPEOF) \
+ 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)
+
+
+static Token::Value KeywordOrIdentifierToken(const uint8_t* input,
+ int input_length, bool escaped) {
+ DCHECK(input_length >= 1);
+ const int kMinLength = 2;
+ const int kMaxLength = 10;
+ 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); \
+ 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])) { \
+ if (escaped) { \
+ return token == Token::FUTURE_STRICT_RESERVED_WORD \
+ ? Token::ESCAPED_STRICT_RESERVED_WORD \
+ : Token::ESCAPED_KEYWORD; \
+ } \
+ return token; \
+ } \
+ }
+ KEYWORDS(KEYWORD_GROUP_CASE, KEYWORD)
+ }
+ return Token::IDENTIFIER;
+}
+
+
+bool Scanner::IdentifierIsFutureStrictReserved(
+ const AstRawString* string) const {
+ // Keywords are always 1-byte strings.
+ if (!string->is_one_byte()) return false;
+ if (string->IsOneByteEqualTo("let") || string->IsOneByteEqualTo("static") ||
+ string->IsOneByteEqualTo("yield")) {
+ return true;
+ }
+ return Token::FUTURE_STRICT_RESERVED_WORD ==
+ KeywordOrIdentifierToken(string->raw_data(), string->length(), false);
+}
+
+
+Token::Value Scanner::ScanIdentifierOrKeyword() {
+ DCHECK(unicode_cache_->IsIdentifierStart(c0_));
+ LiteralScope literal(this);
+ if (IsInRange(c0_, 'a', 'z')) {
+ do {
+ uc32 first_char = c0_;
+ Advance<false, false>();
+ AddLiteralChar(first_char);
+ } while (IsInRange(c0_, 'a', 'z'));
+
+ if (IsDecimalDigit(c0_) || IsInRange(c0_, 'A', 'Z') || c0_ == '_' ||
+ c0_ == '$') {
+ // Identifier starting with lowercase.
+ uc32 first_char = c0_;
+ Advance<false, false>();
+ AddLiteralChar(first_char);
+ while (IsAsciiIdentifier(c0_)) {
+ uc32 first_char = c0_;
+ Advance<false, false>();
+ AddLiteralChar(first_char);
+ }
+ if (c0_ <= kMaxAscii && c0_ != '\\') {
+ literal.Complete();
+ return Token::IDENTIFIER;
+ }
+ } else if (c0_ <= kMaxAscii && c0_ != '\\') {
+ // Only a-z+: could be a keyword or identifier.
+ literal.Complete();
+ Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal();
+ return KeywordOrIdentifierToken(chars.start(), chars.length(), false);
+ }
+
+ HandleLeadSurrogate();
+ } else if (IsInRange(c0_, 'A', 'Z') || c0_ == '_' || c0_ == '$') {
+ do {
+ uc32 first_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_ >= 0 && 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);
+ }
+
+ literal.Complete();
+
+ if (next_.literal_chars->is_one_byte()) {
+ Vector<const uint8_t> chars = next_.literal_chars->one_byte_literal();
+ return KeywordOrIdentifierToken(chars.start(), chars.length(), false);
+ }
+ return Token::IDENTIFIER;
+}
+
+
+Token::Value Scanner::ScanIdentifierSuffix(LiteralScope* literal,
+ bool escaped) {
+ // Scan the rest of the identifier characters.
+ while (c0_ >= 0 && 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();
+ return KeywordOrIdentifierToken(chars.start(), chars.length(), true);
+ }
+ return Token::IDENTIFIER;
+}
+
+
+bool Scanner::ScanRegExpPattern(bool seen_equal) {
+ // Scan: ('/' | '/=') RegularExpressionBody '/' RegularExpressionFlags
+ bool in_character_class = false;
+
+ // 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_ < 0 || unicode_cache_->IsLineTerminator(c0_)) return false;
+ if (c0_ == '\\') { // Escape sequence.
+ AddLiteralCharAdvance();
+ if (c0_ < 0 || unicode_cache_->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 throughly 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();
+
+ return true;
+}
+
+
+Maybe<RegExp::Flags> Scanner::ScanRegExpFlags() {
+ // Scan regular expression flags.
+ LiteralScope literal(this);
+ int flags = 0;
+ while (c0_ >= 0 && 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 'u':
+ if (!FLAG_harmony_unicode_regexps) return Nothing<RegExp::Flags>();
+ flag = RegExp::kUnicode;
+ break;
+ case 'y':
+ if (!FLAG_harmony_regexps) return Nothing<RegExp::Flags>();
+ flag = RegExp::kSticky;
+ break;
+ default:
+ return Nothing<RegExp::Flags>();
+ }
+ if (flags & flag) return Nothing<RegExp::Flags>();
+ AddLiteralCharAdvance();
+ flags |= flag;
+ }
+ literal.Complete();
+
+ next_.location.end_pos = source_pos();
+ return Just(RegExp::Flags(flags));
+}
+
+
+const AstRawString* Scanner::CurrentSymbol(AstValueFactory* ast_value_factory) {
+ 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) {
+ 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) {
+ 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);
+}
+
+
+bool Scanner::ContainsDot() {
+ DCHECK(is_literal_one_byte());
+ Vector<const uint8_t> str = literal_one_byte_string();
+ return std::find(str.begin(), str.end(), '.') != str.end();
+}
+
+
+int Scanner::FindSymbol(DuplicateFinder* finder, int value) {
+ if (is_literal_one_byte()) {
+ return finder->AddOneByteSymbol(literal_one_byte_string(), value);
+ }
+ return finder->AddTwoByteSymbol(literal_two_byte_string(), value);
+}
+
+
+bool Scanner::SetBookmark() {
+ if (c0_ != kNoBookmark && bookmark_c0_ == kNoBookmark &&
+ next_next_.token == Token::UNINITIALIZED && source_->SetBookmark()) {
+ bookmark_c0_ = c0_;
+ CopyTokenDesc(&bookmark_current_, ¤t_);
+ CopyTokenDesc(&bookmark_next_, &next_);
+ return true;
+ }
+ return false;
+}
+
+
+void Scanner::ResetToBookmark() {
+ DCHECK(BookmarkHasBeenSet()); // Caller hasn't called SetBookmark.
+
+ source_->ResetToBookmark();
+ c0_ = bookmark_c0_;
+ StartLiteral();
+ StartRawLiteral();
+ CopyTokenDesc(&next_, &bookmark_current_);
+ current_ = next_;
+ StartLiteral();
+ StartRawLiteral();
+ CopyTokenDesc(&next_, &bookmark_next_);
+
+ bookmark_c0_ = kBookmarkWasApplied;
+}
+
+
+bool Scanner::BookmarkHasBeenSet() { return bookmark_c0_ >= 0; }
+
+
+bool Scanner::BookmarkHasBeenReset() {
+ return bookmark_c0_ == kBookmarkWasApplied;
+}
+
+
+void Scanner::DropBookmark() { bookmark_c0_ = kNoBookmark; }
+
+
+void Scanner::CopyTokenDesc(TokenDesc* to, TokenDesc* from) {
+ DCHECK_NOT_NULL(to);
+ DCHECK_NOT_NULL(from);
+ to->token = from->token;
+ to->location = from->location;
+ to->literal_chars->CopyFrom(from->literal_chars);
+ to->raw_literal_chars->CopyFrom(from->raw_literal_chars);
+}
+
+
+int DuplicateFinder::AddOneByteSymbol(Vector<const uint8_t> key, int value) {
+ return AddSymbol(key, true, value);
+}
+
+
+int DuplicateFinder::AddTwoByteSymbol(Vector<const uint16_t> key, int value) {
+ return AddSymbol(Vector<const uint8_t>::cast(key), false, value);
+}
+
+
+int DuplicateFinder::AddSymbol(Vector<const uint8_t> key,
+ bool is_one_byte,
+ int value) {
+ uint32_t hash = Hash(key, is_one_byte);
+ byte* encoding = BackupKey(key, is_one_byte);
+ HashMap::Entry* entry = map_.LookupOrInsert(encoding, hash);
+ int old_value = static_cast<int>(reinterpret_cast<intptr_t>(entry->value));
+ entry->value =
+ reinterpret_cast<void*>(static_cast<intptr_t>(value | old_value));
+ return old_value;
+}
+
+
+int DuplicateFinder::AddNumber(Vector<const uint8_t> key, int value) {
+ DCHECK(key.length() > 0);
+ // Quick check for already being in canonical form.
+ if (IsNumberCanonical(key)) {
+ return AddOneByteSymbol(key, value);
+ }
+
+ int flags = ALLOW_HEX | ALLOW_OCTAL | ALLOW_IMPLICIT_OCTAL | ALLOW_BINARY;
+ double double_value = StringToDouble(
+ unicode_constants_, key, flags, 0.0);
+ int length;
+ const char* string;
+ if (!std::isfinite(double_value)) {
+ string = "Infinity";
+ length = 8; // strlen("Infinity");
+ } else {
+ string = DoubleToCString(double_value,
+ Vector<char>(number_buffer_, kBufferSize));
+ length = StrLength(string);
+ }
+ return AddSymbol(Vector<const byte>(reinterpret_cast<const byte*>(string),
+ length), true, value);
+}
+
+
+bool DuplicateFinder::IsNumberCanonical(Vector<const uint8_t> number) {
+ // Test for a safe approximation of number literals that are already
+ // in canonical form: max 15 digits, no leading zeroes, except an
+ // integer part that is a single zero, and no trailing zeros below
+ // the decimal point.
+ int pos = 0;
+ int length = number.length();
+ if (number.length() > 15) return false;
+ if (number[pos] == '0') {
+ pos++;
+ } else {
+ while (pos < length &&
+ static_cast<unsigned>(number[pos] - '0') <= ('9' - '0')) pos++;
+ }
+ if (length == pos) return true;
+ if (number[pos] != '.') return false;
+ pos++;
+ bool invalid_last_digit = true;
+ while (pos < length) {
+ uint8_t digit = number[pos] - '0';
+ if (digit > '9' - '0') return false;
+ invalid_last_digit = (digit == 0);
+ pos++;
+ }
+ return !invalid_last_digit;
+}
+
+
+uint32_t DuplicateFinder::Hash(Vector<const uint8_t> key, bool is_one_byte) {
+ // Primitive hash function, almost identical to the one used
+ // for strings (except that it's seeded by the length and representation).
+ int length = key.length();
+ uint32_t hash = (length << 1) | (is_one_byte ? 1 : 0);
+ for (int i = 0; i < length; i++) {
+ uint32_t c = key[i];
+ hash = (hash + c) * 1025;
+ hash ^= (hash >> 6);
+ }
+ return hash;
+}
+
+
+bool DuplicateFinder::Match(void* first, void* second) {
+ // Decode lengths.
+ // Length + representation is encoded as base 128, most significant heptet
+ // first, with a 8th bit being non-zero while there are more heptets.
+ // The value encodes the number of bytes following, and whether the original
+ // was Latin1.
+ byte* s1 = reinterpret_cast<byte*>(first);
+ byte* s2 = reinterpret_cast<byte*>(second);
+ uint32_t length_one_byte_field = 0;
+ byte c1;
+ do {
+ c1 = *s1;
+ if (c1 != *s2) return false;
+ length_one_byte_field = (length_one_byte_field << 7) | (c1 & 0x7f);
+ s1++;
+ s2++;
+ } while ((c1 & 0x80) != 0);
+ int length = static_cast<int>(length_one_byte_field >> 1);
+ return memcmp(s1, s2, length) == 0;
+}
+
+
+byte* DuplicateFinder::BackupKey(Vector<const uint8_t> bytes,
+ bool is_one_byte) {
+ uint32_t one_byte_length = (bytes.length() << 1) | (is_one_byte ? 1 : 0);
+ backing_store_.StartSequence();
+ // Emit one_byte_length as base-128 encoded number, with the 7th bit set
+ // on the byte of every heptet except the last, least significant, one.
+ if (one_byte_length >= (1 << 7)) {
+ if (one_byte_length >= (1 << 14)) {
+ if (one_byte_length >= (1 << 21)) {
+ if (one_byte_length >= (1 << 28)) {
+ backing_store_.Add(
+ static_cast<uint8_t>((one_byte_length >> 28) | 0x80));
+ }
+ backing_store_.Add(
+ static_cast<uint8_t>((one_byte_length >> 21) | 0x80u));
+ }
+ backing_store_.Add(
+ static_cast<uint8_t>((one_byte_length >> 14) | 0x80u));
+ }
+ backing_store_.Add(static_cast<uint8_t>((one_byte_length >> 7) | 0x80u));
+ }
+ backing_store_.Add(static_cast<uint8_t>(one_byte_length & 0x7f));
+
+ backing_store_.AddBlock(bytes);
+ return backing_store_.EndSequence().start();
+}
+
+} // namespace internal
+} // namespace v8