Elide hole checks on KeyedLoads of holey double arrays.

src/contexts.h

Index: src/contexts.h
diff --git a/src/contexts.h b/src/contexts.h
index 721d6699a81f5a8940e4f53c642c52e2a7028c8c..86406e5a09756da95984c740bd60b258c1fd12c3 100644
--- a/src/contexts.h
+++ b/src/contexts.h
@@ -112,6 +112,7 @@ enum BindingFlags {
   V(JSON_OBJECT_INDEX, JSObject, json_object) \
   V(REGEXP_FUNCTION_INDEX, JSFunction, regexp_function) \
   V(INITIAL_OBJECT_PROTOTYPE_INDEX, JSObject, initial_object_prototype) \
+  V(INITIAL_ARRAY_PROTOTYPE_INDEX, JSObject, initial_array_prototype) \
   V(CREATE_DATE_FUN_INDEX, JSFunction,  create_date_fun) \
   V(TO_NUMBER_FUN_INDEX, JSFunction, to_number_fun) \
   V(TO_STRING_FUN_INDEX, JSFunction, to_string_fun) \
@@ -258,6 +259,7 @@ class Context: public FixedArray {
     FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX,
     STRICT_MODE_FUNCTION_WITHOUT_PROTOTYPE_MAP_INDEX,
     INITIAL_OBJECT_PROTOTYPE_INDEX,
+    INITIAL_ARRAY_PROTOTYPE_INDEX,
     BOOLEAN_FUNCTION_INDEX,
     NUMBER_FUNCTION_INDEX,
     STRING_FUNCTION_INDEX,
@@ -429,6 +431,10 @@ class Context: public FixedArray {
     ASSERT(IsNativeContext());                            \
     set(index, value);                                    \
   }                                                       \
+  bool is_##name(type* value) {                           \
+    ASSERT(IsNativeContext());                            \
+    return type::cast(get(index)) == value;               \
+  }                                                       \
   type* name() {                                          \
     ASSERT(IsNativeContext());                            \
     return type::cast(get(index));                        \