Optimize the lexical scanner by selective inlining, and...

src/scanner.h

 // Copyright 2006-2008 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 21 matching lines @@
 #include "char-predicates-inl.h"
 
 namespace v8 { namespace internal {
 
 
 class UTF8Buffer {
  public:
   UTF8Buffer();
   ~UTF8Buffer();
 
-  void Initialize(char* src, int length);
-  void AddChar(uc32 c);
-  void Reset() { pos_ = 0; }
-  int pos() const { return pos_; }
+  void AddChar(uc32 c) {
+    if (cursor_ <= limit_ &&
+        static_cast<unsigned>(c) <= unibrow::Utf8::kMaxOneByteChar) {
+      *cursor_++ = static_cast<char>(c);
+    } else {
+      AddCharSlow(c);
+    }
+  }
+
+  void Reset() { cursor_ = data_; }
+  int pos() const { return cursor_ - data_; }
   char* data() const { return data_; }
 
  private:
   char* data_;
-  int size_;
-  int pos_;
+  char* cursor_;
+  char* limit_;
+
+  int Capacity() const {
+    return (limit_ - data_) + unibrow::Utf8::kMaxEncodedSize;
+  }
+
+  static char* ComputeLimit(char* data, int capacity) {
+    return (data + capacity) - unibrow::Utf8::kMaxEncodedSize;
+  }
+
+  void AddCharSlow(uc32 c);
 };
 
 
 class UTF16Buffer {
  public:
   UTF16Buffer();
 
   void Initialize(Handle<String> data, unibrow::CharacterStream* stream);
   void PushBack(uc32 ch);
   uc32 Advance();  // returns a value < 0 when the buffer end is reached
@@ skipping 135 matching lines @@
   // Literal buffer support
   void StartLiteral();
   void AddChar(uc32 ch);
   void AddCharAdvance();
   void TerminateLiteral();
 
   // Low-level scanning support.
   void Advance();
   void PushBack(uc32 ch);
 
-  void SkipWhiteSpace(bool initial);
+  bool SkipWhiteSpace();
   Token::Value SkipSingleLineComment();
   Token::Value SkipMultiLineComment();
 
   inline Token::Value Select(Token::Value tok);
   inline Token::Value Select(uc32 next, Token::Value then, Token::Value else_);
 
   void Scan();
-  Token::Value ScanToken();
   void ScanDecimalDigits();
   Token::Value ScanNumber(bool seen_period);
   Token::Value ScanIdentifier();
   uc32 ScanHexEscape(uc32 c, int length);
   uc32 ScanOctalEscape(uc32 c, int length);
   void ScanEscape();
   Token::Value ScanString();
 
   // Scans a possible HTML comment -- begins with '<!'.
   Token::Value ScanHtmlComment();
 
   // Return the current source position.
   int source_pos() {
     return source_.pos() - kCharacterLookaheadBufferSize + position_;
   }
 
   // Decodes a unicode escape-sequence which is part of an identifier.
   // If the escape sequence cannot be decoded the result is kBadRune.
   uc32 ScanIdentifierUnicodeEscape();
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCANNER_H_