Opt compiler: Basic simplification for arithmetic operations.

The optimisations in this patch do not look further than the
inputs of each operation.

Change-Id: Iddd0ab6b360b9e7bb042db22086d51a31be85530
diff --git a/runtime/primitive.h b/runtime/primitive.h
index 9dda144..2d6b6b3 100644
--- a/runtime/primitive.h
+++ b/runtime/primitive.h
@@ -165,6 +165,10 @@
     }
   }
 
+  static bool IsIntOrLongType(Type type) {
+    return type == kPrimInt || type == kPrimLong;
+  }
+
   static bool Is64BitType(Type type) {
     return type == kPrimLong || type == kPrimDouble;
   }