Use a WeakCell in the CallIC type vector.

src/type-feedback-vector.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/v8.h"
 
 #include "src/ic/ic.h"
 #include "src/ic/ic-state.h"
 #include "src/objects.h"
 #include "src/type-feedback-vector-inl.h"
@@ skipping 120 matching lines @@
 
 
 // This logic is copied from
 // StaticMarkingVisitor<StaticVisitor>::VisitCodeTarget.
 // TODO(mvstanton): with weak handling of all vector ics, this logic should
 // actually be completely eliminated and we no longer need to clear the
 // vector ICs.
 static bool ClearLogic(Heap* heap, int ic_age, Code::Kind kind,
                        InlineCacheState state) {
   if (FLAG_cleanup_code_caches_at_gc &&
-      (kind == Code::CALL_IC || heap->flush_monomorphic_ics() ||
+      (heap->flush_monomorphic_ics() ||
        // TODO(mvstanton): is this ic_age granular enough? it comes from
        // the SharedFunctionInfo which may change on a different schedule
        // than ic targets.
        // ic_age != heap->global_ic_age() ||
        // is_invalidated_weak_stub ||
        heap->isolate()->serializer_enabled())) {
     return true;
   }
   return false;
 }
@@ skipping 126 matching lines @@
   return UNINITIALIZED;
 }
 
 
 InlineCacheState CallICNexus::StateFromFeedback() const {
   Isolate* isolate = GetIsolate();
   Object* feedback = GetFeedback();
 
   if (feedback == *vector()->MegamorphicSentinel(isolate)) {
     return GENERIC;
-  } else if (feedback->IsAllocationSite() || feedback->IsJSFunction()) {
+  } else if (feedback->IsAllocationSite() || feedback->IsWeakCell()) {
     return MONOMORPHIC;
   }
 
   CHECK(feedback == *vector()->UninitializedSentinel(isolate));
   return UNINITIALIZED;
 }
 
 
 void CallICNexus::Clear(Code* host) { CallIC::Clear(GetIsolate(), host, this); }
 
@@ skipping 13 matching lines @@
 }
 
 
 void CallICNexus::ConfigureUninitialized() {
   SetFeedback(*vector()->UninitializedSentinel(GetIsolate()),
               SKIP_WRITE_BARRIER);
 }
 
 
 void CallICNexus::ConfigureMonomorphic(Handle<JSFunction> function) {
-  SetFeedback(*function);
+  Handle<WeakCell> new_cell = GetIsolate()->factory()->NewWeakCell(function);
+  SetFeedback(*new_cell);
 }
 
 
 void KeyedLoadICNexus::ConfigureGeneric() {
   SetFeedback(*vector()->GenericSentinel(GetIsolate()), SKIP_WRITE_BARRIER);
 }
 
 
 void LoadICNexus::ConfigureMegamorphic() {
   SetFeedback(*vector()->MegamorphicSentinel(GetIsolate()), SKIP_WRITE_BARRIER);
@@ skipping 174 matching lines @@
   if (feedback->IsFixedArray()) {
     FixedArray* array = FixedArray::cast(feedback);
     DCHECK(array->length() >= 3);
     Object* name = array->get(0);
     if (name->IsName()) return Name::cast(name);
   }
   return NULL;
 }
 }
 }  // namespace v8::internal