Maintain a FixedArray for the optimized code map.

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/base/bits.h"
 #include "src/base/once.h"
@@ skipping 2768 matching lines @@
 
     Object* megamorphic = *TypeFeedbackVector::MegamorphicSentinel(isolate());
     dummy_vector->Set(load_ic_slot, megamorphic, SKIP_WRITE_BARRIER);
     dummy_vector->Set(keyed_load_ic_slot, megamorphic, SKIP_WRITE_BARRIER);
     dummy_vector->Set(store_ic_slot, megamorphic, SKIP_WRITE_BARRIER);
     dummy_vector->Set(keyed_store_ic_slot, megamorphic, SKIP_WRITE_BARRIER);
 
     set_dummy_vector(*dummy_vector);
   }
 
+  {
+    Handle<FixedArray> cleared_optimized_code_map =
+        factory->NewFixedArray(SharedFunctionInfo::kEntriesStart, TENURED);
+    DCHECK(SharedFunctionInfo::kEntriesStart == 1 &&

[Michael Starzinger, 2015/11/13 12:14:22]

nit: Could be turned into a STATIC_ASSERT instead.

[mvstanton, 2015/11/17 20:32:12]

Done.

+           SharedFunctionInfo::kSharedCodeIndex == 0);
+    cleared_optimized_code_map->set(SharedFunctionInfo::kSharedCodeIndex,

[Michael Starzinger, 2015/11/13 12:14:22]

The field is already initialized to undefined, because Factory::NewFixedArray
produces an initialed array. Explicitly setting this field is not needed.

[mvstanton, 2015/11/17 20:32:12]

Done.

+                                    *factory->undefined_value(),
+                                    SKIP_WRITE_BARRIER);
+    set_cleared_optimized_code_map(*cleared_optimized_code_map);
+  }
+
   set_detached_contexts(empty_fixed_array());
   set_retained_maps(ArrayList::cast(empty_fixed_array()));
 
   set_weak_object_to_code_table(
       *WeakHashTable::New(isolate(), 16, USE_DEFAULT_MINIMUM_CAPACITY,
                           TENURED));
 
   set_script_list(Smi::FromInt(0));
 
   Handle<SeededNumberDictionary> slow_element_dictionary =
@@ skipping 3389 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8