Introduce number type information in the virtual frame.

src/frame-element.cc

Index: src/frame-element.cc
===================================================================
--- src/frame-element.cc	(revision 3859)
+++ src/frame-element.cc	(working copy)
@@ -35,7 +35,18 @@
 // -------------------------------------------------------------------------
 // FrameElement implementation.
 
+NumberInfo::Type FrameElement::number_info() {
+  // Copied elements do not have number info. Instead
+  // we have to inspect their backing element in the frame.
+  ASSERT(!is_copy());
+  if (!is_constant()) return NumberInfoField::decode(value_);
+  Handle<Object> value = handle();
+  if (value->IsSmi()) return NumberInfo::kSmi;
+  if (value->IsHeapNumber()) return NumberInfo::kHeapNumber;
+  return NumberInfo::kUnknown;
+}
 
+
 FrameElement::ZoneObjectList* FrameElement::ConstantList() {
   static ZoneObjectList list(10);
   return &list;