Calling a generator function returns a generator object

src/runtime.cc

Index: src/runtime.cc
diff --git a/src/runtime.cc b/src/runtime.cc
index dcc76181fe488a0aa27a7c734cb7a5be706df303..fde8e9599a0bd080b6e318e78b33036ed9b0d291 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -1,4 +1,4 @@
-// Copyright 2012 the V8 project authors. All rights reserved.
+// Copyright 2012, 2013 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:
@@ -2385,6 +2385,17 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_SetExpectedNumberOfProperties) {
 }
 
 
+RUNTIME_FUNCTION(MaybeObject*, Runtime_CreateJSGeneratorIterator) {
+  HandleScope scope(isolate);
+  ASSERT(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSFunction, function, 0);
+  ASSERT(function->shared()->is_generator());
+  Handle<JSGeneratorIterator> generator =
+      isolate->factory()->NewJSGeneratorIterator(function);
+  return *generator;
+}
+
+
 MUST_USE_RESULT static MaybeObject* CharFromCode(Isolate* isolate,
                                                  Object* char_code) {
   uint32_t code;