Handle ExternalStrings directly in the serializer without ObjectVisitor.

src/objects-body-descriptors-inl.h

 // Copyright 2015 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.
 
 #ifndef V8_OBJECTS_BODY_DESCRIPTORS_INL_H_
 #define V8_OBJECTS_BODY_DESCRIPTORS_INL_H_
 
 #include "src/assembler-inl.h"
 #include "src/objects-body-descriptors.h"
 #include "src/transitions.h"
@@ skipping 336 matching lines @@
   static inline int SizeOf(Map* map, HeapObject* object) { return kSize; }
 };
 
 class ExternalOneByteString::BodyDescriptor final : public BodyDescriptorBase {
  public:
   static bool IsValidSlot(HeapObject* obj, int offset) { return false; }
 
   template <typename ObjectVisitor>
   static inline void IterateBody(HeapObject* obj, int object_size,
                                  ObjectVisitor* v) {
-    typedef v8::String::ExternalOneByteStringResource Resource;
-    v->VisitExternalOneByteString(reinterpret_cast<Resource**>(
-        HeapObject::RawField(obj, kResourceOffset)));
   }
 
   template <typename StaticVisitor>
   static inline void IterateBody(HeapObject* obj, int object_size) {
-    typedef v8::String::ExternalOneByteStringResource Resource;
-    StaticVisitor::VisitExternalOneByteString(reinterpret_cast<Resource**>(
-        HeapObject::RawField(obj, kResourceOffset)));
   }
 
   static inline int SizeOf(Map* map, HeapObject* object) { return kSize; }
 };
 
 class ExternalTwoByteString::BodyDescriptor final : public BodyDescriptorBase {
  public:
   static bool IsValidSlot(HeapObject* obj, int offset) { return false; }
 
   template <typename ObjectVisitor>
   static inline void IterateBody(HeapObject* obj, int object_size,
                                  ObjectVisitor* v) {
-    typedef v8::String::ExternalStringResource Resource;
-    v->VisitExternalTwoByteString(reinterpret_cast<Resource**>(
-        HeapObject::RawField(obj, kResourceOffset)));
   }
 
   template <typename StaticVisitor>
   static inline void IterateBody(HeapObject* obj, int object_size) {
-    typedef v8::String::ExternalStringResource Resource;
-    StaticVisitor::VisitExternalTwoByteString(reinterpret_cast<Resource**>(
-        HeapObject::RawField(obj, kResourceOffset)));
   }
 
   static inline int SizeOf(Map* map, HeapObject* object) { return kSize; }
 };
 
 class Code::BodyDescriptor final : public BodyDescriptorBase {
  public:
   STATIC_ASSERT(kRelocationInfoOffset + kPointerSize == kHandlerTableOffset);
   STATIC_ASSERT(kHandlerTableOffset + kPointerSize ==
                 kDeoptimizationDataOffset);
@@ skipping 252 matching lines @@
 
 template <typename ObjectVisitor>
 void HeapObject::IterateBodyFast(InstanceType type, int object_size,
                                  ObjectVisitor* v) {
   BodyDescriptorApply<CallIterateBody, void>(type, this, object_size, v);
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_OBJECTS_BODY_DESCRIPTORS_INL_H_