Use a WeakCell in the CallIC type vector.

src/ic/ic.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/v8.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/arguments.h"
 #include "src/base/bits.h"
@@ skipping 2199 matching lines @@
 
 void CallIC::HandleMiss(Handle<Object> receiver, Handle<Object> function) {
   CallICState callic_state(target()->extra_ic_state());
   Handle<Object> name = isolate()->factory()->empty_string();
   CallICNexus* nexus = casted_nexus<CallICNexus>();
   Object* feedback = nexus->GetFeedback();
 
   // Hand-coded MISS handling is easier if CallIC slots don't contain smis.
   DCHECK(!feedback->IsSmi());
 
-  if (feedback->IsJSFunction() || !function->IsJSFunction()) {
+  if (feedback->IsWeakCell() || !function->IsJSFunction()) {
     // We are going generic.
     nexus->ConfigureGeneric();
   } else {
     // The feedback is either uninitialized or an allocation site.
     // It might be an allocation site because if we re-compile the full code
     // to add deoptimization support, we call with the default call-ic, and
     // merely need to patch the target to match the feedback.
     // TODO(mvstanton): the better approach is to dispense with patching
     // altogether, which is in progress.
     DCHECK(feedback == *TypeFeedbackVector::UninitializedSentinel(isolate()) ||
@@ skipping 773 matching lines @@
 static const Address IC_utilities[] = {
 #define ADDR(name) FUNCTION_ADDR(name),
     IC_UTIL_LIST(ADDR) NULL
 #undef ADDR
 };
 
 
 Address IC::AddressFromUtilityId(IC::UtilityId id) { return IC_utilities[id]; }
 }
 }  // namespace v8::internal