Inline calling into the interceptor into the IC callbacks rather than going through the LookupItera…

src/ic/handler-compiler.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/ic/handler-compiler.h"
 
 #include "src/field-type.h"
 #include "src/ic/call-optimization.h"
 #include "src/ic/ic-inl.h"
 #include "src/ic/ic.h"
@@ skipping 564 matching lines @@
     } else {
       bool is_js_array = receiver_map->instance_type() == JS_ARRAY_TYPE;
       ElementsKind elements_kind = receiver_map->elements_kind();
 
       // No need to check for an elements-free prototype chain here, the
       // generated stub code needs to check that dynamically anyway.
       bool convert_hole_to_undefined =
           (is_js_array && elements_kind == FAST_HOLEY_ELEMENTS &&
            *receiver_map == isolate()->get_initial_js_array_map(elements_kind));
 
-      if (receiver_map->has_indexed_interceptor()) {
+      if (receiver_map->has_indexed_interceptor() &&
+          !receiver_map->GetIndexedInterceptor()->getter()->IsUndefined() &&
+          !receiver_map->GetIndexedInterceptor()->non_masking()) {
         cached_stub = LoadIndexedInterceptorStub(isolate()).GetCode();
       } else if (IsSloppyArgumentsElements(elements_kind)) {
         cached_stub = KeyedLoadSloppyArgumentsStub(isolate()).GetCode();
       } else if (IsFastElementsKind(elements_kind) ||
                  IsFixedTypedArrayElementsKind(elements_kind)) {
         cached_stub = LoadFastElementStub(isolate(), is_js_array, elements_kind,
                                           convert_hole_to_undefined).GetCode();
       } else {
         DCHECK(elements_kind == DICTIONARY_ELEMENTS);
         LoadICState state = LoadICState(kNoExtraICState);
         cached_stub = LoadDictionaryElementStub(isolate(), state).GetCode();
       }
     }
 
     handlers->Add(cached_stub);
   }
 }
 }  // namespace internal
 }  // namespace v8