DBC: Implement InstanceOf.

runtime/vm/constants_dbc.h

Index: runtime/vm/constants_dbc.h
diff --git a/runtime/vm/constants_dbc.h b/runtime/vm/constants_dbc.h
index 4f8aab93ec22373f9d82a148e12da85e519ef39f..b0a6281bed1bf5ae04a3d15a60aa2bc868ef0972 100644
--- a/runtime/vm/constants_dbc.h
+++ b/runtime/vm/constants_dbc.h
@@ -340,6 +340,12 @@ namespace dart {
 //
 //    Instantiate type arguments PP[D] with instantiator SP[0].
 //
+//  - InstanceOf A
+//
+//    Test if instance SP[-3] with type arguments SP[-2] is (A = 0) or is not
+//    (A = 1) a subtype of SP[-1] using SubtypeTestCache SP[0], with result
+//    placed at top of stack.
+//
 //  - AssertAssignable D
 //
 //    Assert that SP[-3] is assignable to variable named SP[0] of type
@@ -499,6 +505,7 @@ namespace dart {
   V(MoveSpecial,                   A_D, reg, num, ___) \
   V(InstantiateType,                 D, lit, ___, ___) \
   V(InstantiateTypeArgumentsTOS,   A_D, num, lit, ___) \
+  V(InstanceOf,                      A, num, ___, ___) \
   V(AssertAssignable,                D, num, lit, ___) \
   V(AssertBoolean,                   A, num, ___, ___) \
   V(CheckSmi,                        A, reg, ___, ___) \