Made simple instance-of checks fast for unoptimized code.

runtime/lib/object_patch.dart

Index: runtime/lib/object_patch.dart
diff --git a/runtime/lib/object_patch.dart b/runtime/lib/object_patch.dart
index 69723b38039f46b3eec4b1f5770768a6eea5b6eb..719e59220b6e268e084a99d43476689434167ba9 100644
--- a/runtime/lib/object_patch.dart
+++ b/runtime/lib/object_patch.dart
@@ -58,6 +58,11 @@ patch class Object {
   bool _instanceOf(instantiator_type_arguments, type, bool negate)
       native "Object_instanceOf";
 
+  // Group of functions for implementing fast simple instance of.
+  bool _simpleInstanceOf(type) native "Object_simpleInstanceOf";
+  bool _simpleInstanceOfTrue(type) => true;
+  bool _simpleInstanceOfFalse(type) => false;

[regis, 2016/07/14 01:41:45]

The names are slightly confusing. I'd prefer:
_simpleInstanceOfReturnsTrue and _simpleInstanceOfReturnsFalse

[bakster, 2016/07/14 17:59:41]

I used that naming first but I ran into the 80 character limit so many time I
decided to change it to a shorter name.
If you feel strongly about it, I'll be happy to break some lines.
//Lars

+  
   bool _instanceOfDouble(bool negate) native "Object_instanceOfDouble";
   bool _instanceOfNum(bool negate) native "Object_instanceOfNum";
   bool _instanceOfInt(bool negate) native "Object_instanceOfInt";