Make frequent type checks (instanceof) faster by adding dedicated instanceof methods; improves dart…

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index 79689346507076d9ad80316a2a4888335a6b6dd2..6f88bbdc2685b86f60028bdb277ef74386ec688e 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -14898,6 +14898,12 @@ bool AbstractType::IsNumberType() const {
 }
 
 
+bool AbstractType::IsSmiType() const {
+  return HasResolvedTypeClass() &&
+      (type_class() == Type::Handle(Type::SmiType()).type_class());
+}
+
+
 bool AbstractType::IsStringType() const {
   return HasResolvedTypeClass() &&
       (type_class() == Type::Handle(Type::StringType()).type_class());