Flat string reader

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 8b1cb2c8a3b2139eec7dbab54fc5d8b55da2b30e..75100bd51f9470063b831c99b7937fea1a9fadf3 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -3590,6 +3590,25 @@ class ExternalTwoByteString: public ExternalString {
 };
 
 
+class FlatStringReader {
+public:
+  explicit FlatStringReader(Handle<String> str);

[Erik Corry, 2008/11/19 09:45:38]

FlatStringReaders can only be stack allocated, right?  So it should be marked as
such.  Also if it is used with some kinds of handles there could be issues
around the lifetime of the handle vs lifetime of the FlatStringReader.  That
deserves a comment.

+  explicit FlatStringReader(Vector<const char> input);
+  ~FlatStringReader();
+  void RefreshState();
+  inline uc32 Get(int index);
+  int length() { return length_; }
+  static void PostGarbageCollectionProcessing();
+private:
+  String** str_;
+  bool is_ascii_;
+  int length_;
+  const void* start_;
+  FlatStringReader* prev_;
+  static FlatStringReader* top_;
+};
+
+
 // Note that StringInputBuffers are not valid across a GC!  To fix this
 // it would have to store a String Handle instead of a String* and
 // AsciiStringReadBlock would have to be modified to use memcpy.