Move most scanner buffer accesses into scanner.

src/scanner.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 158 matching lines @@
   int AddAsciiSymbol(Vector<const char> key, int value);
   int AddUtf16Symbol(Vector<const uint16_t> key, int value);
   // Add a a number literal by converting it (if necessary)
   // to the string that ToString(ToNumber(literal)) would generate.
   // and then adding that string with AddAsciiSymbol.
   // This string is the actual value used as key in an object literal,
   // and the one that must be different from the other keys.
   int AddNumber(Vector<const char> key, int value);
 
  private:
-  int AddSymbol(Vector<const byte> key, bool is_ascii, int value);
+  int AddSymbol(Vector<const byte> key, bool is_one_byte, int value);
   // Backs up the key and its length in the backing store.
   // The backup is stored with a base 127 encoding of the
   // length (plus a bit saying whether the string is ASCII),
   // followed by the bytes of the key.
-  byte* BackupKey(Vector<const byte> key, bool is_ascii);
+  byte* BackupKey(Vector<const byte> key, bool is_one_byte);
 
   // Compare two encoded keys (both pointing into the backing store)
   // for having the same base-127 encoded lengths and ASCII-ness,
   // and then having the same 'length' bytes following.
   static bool Match(void* first, void* second);
   // Creates a hash from a sequence of bytes.
-  static uint32_t Hash(Vector<const byte> key, bool is_ascii);
+  static uint32_t Hash(Vector<const byte> key, bool is_one_byte);
   // Checks whether a string containing a JS number is its canonical
   // form.
   static bool IsNumberCanonical(Vector<const char> key);
 
   // Size of buffer. Sufficient for using it to call DoubleToCString in
   // from conversions.h.
   static const int kBufferSize = 100;
 
   UnicodeCache* unicode_constants_;
   // Backing store used to store strings used as hashmap keys.
   SequenceCollector<unsigned char> backing_store_;
   HashMap map_;
   // Buffer used for string->number->canonical string conversions.
   char number_buffer_[kBufferSize];
 };
 
 
 // ----------------------------------------------------------------------------
 // LiteralBuffer -  Collector of chars of literals.
 
 class LiteralBuffer {
  public:
-  LiteralBuffer() : is_ascii_(true), position_(0), backing_store_() { }
+  LiteralBuffer() : is_one_byte_(true), position_(0), backing_store_() { }
 
   ~LiteralBuffer() {
     if (backing_store_.length() > 0) {
       backing_store_.Dispose();
     }
   }
 
   INLINE(void AddChar(uint32_t code_unit)) {
     if (position_ >= backing_store_.length()) ExpandBuffer();
-    if (is_ascii_) {
+    if (is_one_byte_) {
       if (code_unit <= unibrow::Latin1::kMaxChar) {
         backing_store_[position_] = static_cast<byte>(code_unit);
         position_ += kOneByteSize;
         return;
       }
       ConvertToUtf16();
     }
     ASSERT(code_unit < 0x10000u);
     *reinterpret_cast<uc16*>(&backing_store_[position_]) = code_unit;
     position_ += kUC16Size;
   }
 
-  bool is_ascii() { return is_ascii_; }
+  bool is_one_byte() { return is_one_byte_; }
 
   bool is_contextual_keyword(Vector<const char> keyword) {
-    return is_ascii() && keyword.length() == position_ &&
+    return is_one_byte() && keyword.length() == position_ &&
         (memcmp(keyword.start(), backing_store_.start(), position_) == 0);
   }
 
   Vector<const uc16> utf16_literal() {
-    ASSERT(!is_ascii_);
+    ASSERT(!is_one_byte_);
     ASSERT((position_ & 0x1) == 0);
     return Vector<const uc16>(
         reinterpret_cast<const uc16*>(backing_store_.start()),
         position_ >> 1);
   }
 
-  Vector<const char> ascii_literal() {
-    ASSERT(is_ascii_);
+  Vector<const char> one_byte_literal() {
+    ASSERT(is_one_byte_);
     return Vector<const char>(
         reinterpret_cast<const char*>(backing_store_.start()),
         position_);
   }
 
   int length() {
-    return is_ascii_ ? position_ : (position_ >> 1);
+    return is_one_byte_ ? position_ : (position_ >> 1);
   }
 
   void Reset() {
     position_ = 0;
-    is_ascii_ = true;
+    is_one_byte_ = true;
   }
 
  private:
   static const int kInitialCapacity = 16;
   static const int kGrowthFactory = 4;
   static const int kMinConversionSlack = 256;
   static const int kMaxGrowth = 1 * MB;
   inline int NewCapacity(int min_capacity) {
     int capacity = Max(min_capacity, backing_store_.length());
     int new_capacity = Min(capacity * kGrowthFactory, capacity + kMaxGrowth);
     return new_capacity;
   }
 
   void ExpandBuffer() {
     Vector<byte> new_store = Vector<byte>::New(NewCapacity(kInitialCapacity));
     OS::MemCopy(new_store.start(), backing_store_.start(), position_);
     backing_store_.Dispose();
     backing_store_ = new_store;
   }
 
   void ConvertToUtf16() {
-    ASSERT(is_ascii_);
+    ASSERT(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();
     uc16* dst = reinterpret_cast<uc16*>(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_ascii_ = false;
+    is_one_byte_ = false;
   }
 
-  bool is_ascii_;
+  bool is_one_byte_;
   int position_;
   Vector<byte> backing_store_;
 
   DISALLOW_COPY_AND_ASSIGN(LiteralBuffer);
 };
 
 
 // ----------------------------------------------------------------------------
 // JavaScript Scanner.
 
@@ skipping 48 matching lines @@
   Token::Value current_token() { return current_.token; }
   // Returns the location information for the current token
   // (the token last returned by Next()).
   Location location() const { return current_.location; }
   // Returns the literal string, if any, for the current token (the
   // token last returned by Next()). The string is 0-terminated.
   // 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().
-  Vector<const char> literal_ascii_string() {
+  Vector<const char> literal_one_byte_string() {
     ASSERT_NOT_NULL(current_.literal_chars);
-    return current_.literal_chars->ascii_literal();
+    return current_.literal_chars->one_byte_literal();
   }
   Vector<const uc16> literal_utf16_string() {
     ASSERT_NOT_NULL(current_.literal_chars);
     return current_.literal_chars->utf16_literal();
   }
-  bool is_literal_ascii() {
+  bool is_literal_one_byte() {
     ASSERT_NOT_NULL(current_.literal_chars);
-    return current_.literal_chars->is_ascii();
+    return current_.literal_chars->is_one_byte();
   }
   bool is_literal_contextual_keyword(Vector<const char> keyword) {
     ASSERT_NOT_NULL(current_.literal_chars);
     return current_.literal_chars->is_contextual_keyword(keyword);
   }
   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;
   }
 
   // Similar functions for the upcoming token.
 
   // One token look-ahead (past the token returned by Next()).
   Token::Value peek() const { return next_.token; }
 
   Location peek_location() const { return next_.location; }
 
   // Returns the literal string for the next token (the token that
   // would be returned if Next() were called).
-  Vector<const char> next_literal_ascii_string() {
+  Vector<const char> next_literal_one_byte_string() {
     ASSERT_NOT_NULL(next_.literal_chars);
-    return next_.literal_chars->ascii_literal();
+    return next_.literal_chars->one_byte_literal();
   }
   Vector<const uc16> next_literal_utf16_string() {
     ASSERT_NOT_NULL(next_.literal_chars);
     return next_.literal_chars->utf16_literal();
   }
-  bool is_next_literal_ascii() {
+  bool is_next_literal_one_byte() {
     ASSERT_NOT_NULL(next_.literal_chars);
-    return next_.literal_chars->is_ascii();
+    return next_.literal_chars->is_one_byte();
   }
   bool is_next_contextual_keyword(Vector<const char> keyword) {
     ASSERT_NOT_NULL(next_.literal_chars);
     return next_.literal_chars->is_contextual_keyword(keyword);
   }
   int next_literal_length() const {
     ASSERT_NOT_NULL(next_.literal_chars);
     return next_.literal_chars->length();
   }
 
+  Handle<String> AllocateLiteralString(Isolate* isolate, PretenureFlag tenured);
+  Handle<String> AllocateNextLiteralString(Isolate* isolate,
+                                           PretenureFlag tenured);
+  Handle<String> AllocateInternalizedString(Isolate* isolate);
+
+  double DoubleValue();
+  bool UnescapedLiteralMatches(const char* data, int length) {
+    if (is_literal_one_byte() &&
+        literal_length() == length &&
+        !literal_contains_escapes()) {
+      return !strncmp(literal_one_byte_string().start(), data, length);
+    }
+    return false;
+  }
+  void IsGetOrSet(bool* is_get, bool* is_set) {
+    if (is_literal_one_byte() &&
+        literal_length() == 3 &&
+        !literal_contains_escapes()) {
+      const char* token = literal_one_byte_string().start();
+      *is_get = strncmp(token, "get", 3) == 0;
+      *is_set = !*is_get && strncmp(token, "set", 3) == 0;
+    }
+  }
+
   UnicodeCache* unicode_cache() { return unicode_cache_; }
 
   static const int kCharacterLookaheadBufferSize = 1;
 
   // 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(); }
@@ skipping 170 matching lines @@
   bool harmony_scoping_;
   // Whether we scan 'module', 'import', 'export' as keywords.
   bool harmony_modules_;
   // Whether we scan 0o777 and 0b111 as numbers.
   bool harmony_numeric_literals_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCANNER_H_