Updated the check for unmodfied objects to handle Smi Objects.

src/heap/heap.cc

 // Copyright 2012 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/heap/heap.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/ast/scopeinfo.h"
 #include "src/base/bits.h"
@@ skipping 1475 matching lines @@
 
 
 static bool IsUnscavengedHeapObject(Heap* heap, Object** p) {
   return heap->InNewSpace(*p) &&
          !HeapObject::cast(*p)->map_word().IsForwardingAddress();
 }
 
 
 static bool IsUnmodifiedHeapObject(Object** p) {
   Object* object = *p;
-  DCHECK(object->IsHeapObject());
+  if (object->IsSmi()) return false;
   HeapObject* heap_object = HeapObject::cast(object);
   if (!object->IsJSObject()) return false;
   Object* obj_constructor = (JSObject::cast(object))->map()->GetConstructor();
   if (!obj_constructor->IsJSFunction()) return false;
   JSFunction* constructor = JSFunction::cast(obj_constructor);
+  if (!constructor->shared()->IsApiFunction()) return false;
   if (constructor != nullptr &&
       constructor->initial_map() == heap_object->map()) {
     return true;
   }
   return false;
 }
 
 
 void Heap::ScavengeStoreBufferCallback(Heap* heap, MemoryChunk* page,
                                        StoreBufferEvent event) {
@@ skipping 4587 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8