Fix missing write barrier in store field stub.

src/x64/stub-cache-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 750 matching lines @@
     __ push(scratch);
     __ TailCallExternalReference(
         ExternalReference(IC_Utility(IC::kSharedStoreIC_ExtendStorage),
                           masm->isolate()),
         3,
         1);
     return;
   }
 
   if (!transition.is_null()) {
-    // Update the map of the object; no write barrier updating is
-    // needed because the map is never in new space.
-    __ Move(FieldOperand(receiver_reg, HeapObject::kMapOffset), transition);
+    // Update the map of the object.
+    __ Move(scratch, transition);
+    __ movq(FieldOperand(receiver_reg, HeapObject::kMapOffset), scratch);
+
+    // Update the write barrier for the map field and pass the now unused
+    // name_reg as scratch register.
+    __ RecordWriteField(receiver_reg,
+                        HeapObject::kMapOffset,
+                        scratch,
+                        name_reg,
+                        kDontSaveFPRegs,
+                        OMIT_REMEMBERED_SET,
+                        OMIT_SMI_CHECK);
   }
 
   // Adjust for the number of properties stored in the object. Even in the
   // face of a transition we can use the old map here because the size of the
   // object and the number of in-object properties is not going to change.
   index -= object->map()->inobject_properties();
 
   if (index < 0) {
     // Set the property straight into the object.
     int offset = object->map()->instance_size() + (index * kPointerSize);
@@ skipping 3068 matching lines @@
     __ jmp(ic_slow, RelocInfo::CODE_TARGET);
   }
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64