Use weak cells in dependent code.

src/objects-debug.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/disasm.h"
 #include "src/disassembler.h"
 #include "src/heap/objects-visiting.h"
 #include "src/jsregexp.h"
@@ skipping 655 matching lines @@
       last_gc_pc = it.rinfo()->pc();
     }
   }
   CHECK(raw_type_feedback_info() == Smi::FromInt(0) ||
         raw_type_feedback_info()->IsSmi() == IsCodeStubOrIC());
 }
 
 
 void Code::VerifyEmbeddedObjectsDependency() {
   if (!CanContainWeakObjects()) return;
+  WeakCell* cell = CachedWeakCell();
   DisallowHeapAllocation no_gc;
   Isolate* isolate = GetIsolate();
   HandleScope scope(isolate);
   int mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT);
   for (RelocIterator it(this, mode_mask); !it.done(); it.next()) {
     Object* obj = it.rinfo()->target_object();
     if (IsWeakObject(obj)) {
       if (obj->IsMap()) {
         Map* map = Map::cast(obj);
         CHECK(map->dependent_code()->Contains(DependentCode::kWeakCodeGroup,
-                                              this));
+                                              cell));
       } else if (obj->IsJSObject()) {
         Object* raw_table = GetIsolate()->heap()->weak_object_to_code_table();
         WeakHashTable* table = WeakHashTable::cast(raw_table);
         Handle<Object> key_obj(obj, isolate);
-        CHECK(DependentCode::cast(table->Lookup(key_obj))->Contains(
-            DependentCode::kWeakCodeGroup, this));
+        CHECK(DependentCode::cast(table->Lookup(key_obj))
+                  ->Contains(DependentCode::kWeakCodeGroup, cell));
       }
     }
   }
 }
 
 
 void JSArray::JSArrayVerify() {
   JSObjectVerify();
   CHECK(length()->IsNumber() || length()->IsUndefined());
   // If a GC was caused while constructing this array, the elements
@@ skipping 547 matching lines @@
     while (map != heap->roots_array_start()[i++]) {
       CHECK_LT(i, Heap::kStrongRootListLength);
     }
   }
 }
 
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal