Strict mode detection in preparser.

src/scanner-base.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 268 matching lines @@
   Token::Value peek() const { return next_.token; }
 
   struct Location {
     Location(int b, int e) : beg_pos(b), end_pos(e) { }
     Location() : beg_pos(0), end_pos(0) { }
 
     bool IsValid() const {
       return beg_pos >= 0 && end_pos >= beg_pos;
     }
 
+    static Location invalid() { return Location(-1, -1); }
+
     int beg_pos;
     int end_pos;
   };
 
-  static Location NoLocation() {
-    return Location(-1, -1);
-  }
-
   // Returns the location information for the current token
   // (the token returned by Next()).
   Location location() const { return current_.location; }
   Location peek_location() const { return next_.location; }
 
-  // Returns the location of the last seen octal literal
-  int octal_position() const { return octal_pos_; }
-  void clear_octal_position() { octal_pos_ = -1; }
-
   // Returns the literal string, if any, for the current token (the
   // token returned by Next()). The string is 0-terminated and in
   // UTF-8 format; they may contain 0-characters. Literal strings are
   // collected for identifiers, strings, and numbers.
   // These functions only give the correct result if the literal
   // was scanned between calls to StartLiteral() and TerminateLiteral().
   bool is_literal_ascii() {
     ASSERT_NOT_NULL(current_.literal_chars);
     return current_.literal_chars->is_ascii();
   }
   Vector<const char> literal_ascii_string() {
     ASSERT_NOT_NULL(current_.literal_chars);
     return current_.literal_chars->ascii_literal();
   }
   Vector<const uc16> literal_uc16_string() {
     ASSERT_NOT_NULL(current_.literal_chars);
     return current_.literal_chars->uc16_literal();
   }
   int literal_length() const {
     ASSERT_NOT_NULL(current_.literal_chars);
     return current_.literal_chars->length();
   }
 
+  bool literal_contains_escapes() const {
+    Location location = current_.location;
+    int source_length = (location.end_pos - location.beg_pos);
+    if (current_.token == Token::STRING) {
+      // Subtract delimiters.
+      source_length -= 2;
+    }
+    return current_.literal_chars->length() != source_length;
+  }
+
   // Returns the literal string for the next token (the token that
   // would be returned if Next() were called).
   bool is_next_literal_ascii() {
     ASSERT_NOT_NULL(next_.literal_chars);
     return next_.literal_chars->is_ascii();
   }
   Vector<const char> next_literal_ascii_string() {
     ASSERT_NOT_NULL(next_.literal_chars);
     return next_.literal_chars->ascii_literal();
   }
@@ skipping 71 matching lines @@
     if (c0_ == next) {
       Advance();
       return then;
     } else {
       return else_;
     }
   }
 
   uc32 ScanHexEscape(uc32 c, int length);
 
-  // Scans octal escape sequence. Also accepts "\0" decimal escape sequence.
-  uc32 ScanOctalEscape(uc32 c, int length);
-
   // Return the current source position.
   int source_pos() {
     return source_->pos() - kCharacterLookaheadBufferSize;
   }
 
   UnicodeCache* unicode_cache_;
 
   // Buffers collecting literal strings, numbers, etc.
   LiteralBuffer literal_buffer1_;
   LiteralBuffer literal_buffer2_;
 
   TokenDesc current_;  // desc for current token (as returned by Next())
   TokenDesc next_;     // desc for next token (one token look-ahead)
 
   // Input stream. Must be initialized to an UC16CharacterStream.
   UC16CharacterStream* source_;
 
-  // Start position of the octal literal last scanned.
-  int octal_pos_;
-
   // One Unicode character look-ahead; c0_ < 0 at the end of the input.
   uc32 c0_;
 };
 
 // ----------------------------------------------------------------------------
 // JavaScriptScanner - base logic for JavaScript scanning.
 
 class JavaScriptScanner : public Scanner {
  public:
   // A LiteralScope that disables recording of some types of JavaScript
@@ skipping 32 matching lines @@
   // character(s) must be /(=). Returns true if a pattern is scanned.
   bool ScanRegExpPattern(bool seen_equal);
   // Returns true if regexp flags are scanned (always since flags can
   // be empty).
   bool ScanRegExpFlags();
 
   // Tells whether the buffer contains an identifier (no escapes).
   // Used for checking if a property name is an identifier.
   static bool IsIdentifier(unibrow::CharacterStream* buffer);
 
+  // Scans octal escape sequence. Also accepts "\0" decimal escape sequence.
+  uc32 ScanOctalEscape(uc32 c, int length);
+
+  // Returns the location of the last seen octal literal
+  Location octal_position() const { return octal_pos_; }
+  void clear_octal_position() { octal_pos_ = Location::invalid(); }
+
   // Seek forward to the given position.  This operation does not
   // work in general, for instance when there are pushed back
   // characters, but works for seeking forward until simple delimiter
   // tokens, which is what it is used for.
   void SeekForward(int pos);
 
  protected:
   bool SkipWhiteSpace();
   Token::Value SkipSingleLineComment();
   Token::Value SkipMultiLineComment();
 
   // Scans a single JavaScript token.
   void Scan();
 
   void ScanDecimalDigits();
   Token::Value ScanNumber(bool seen_period);
   Token::Value ScanIdentifierOrKeyword();
   Token::Value ScanIdentifierSuffix(LiteralScope* literal);
 
   void ScanEscape();
   Token::Value ScanString();
 
   // Scans a possible HTML comment -- begins with '<!'.
   Token::Value ScanHtmlComment();
 
   // Decodes a unicode escape-sequence which is part of an identifier.
   // If the escape sequence cannot be decoded the result is kBadChar.
   uc32 ScanIdentifierUnicodeEscape();
 
+  // Start position of the octal literal last scanned.
+  Location octal_pos_;
+
   bool has_line_terminator_before_next_;
 };
 
 
 // ----------------------------------------------------------------------------
 // Keyword matching state machine.
 
 class KeywordMatcher {
 //  Incrementally recognize keywords.
 //
@@ skipping 119 matching lines @@
   // keyword with the current prefix).
   const char* keyword_;
   int counter_;
   Token::Value keyword_token_;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCANNER_BASE_H_