Make JSFunction::BodyDescriptor the only single place that knows how to iterate JSFunction's body.

src/heap/objects-visiting.h

 // 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.
 
 #ifndef V8_OBJECTS_VISITING_H_
 #define V8_OBJECTS_VISITING_H_
 
 #include "src/allocation.h"
 #include "src/heap/heap.h"
 #include "src/heap/spaces.h"
@@ skipping 233 matching lines @@
 
   INLINE(static int IterateBody(Map* map, HeapObject* obj)) {
     return table_.GetVisitor(map)(map, obj);
   }
 
   INLINE(static void VisitPointers(Heap* heap, HeapObject* object,
                                    Object** start, Object** end)) {
     for (Object** p = start; p < end; p++) StaticVisitor::VisitPointer(heap, p);
   }
 
- private:
-  INLINE(static int VisitJSFunction(Map* map, HeapObject* object)) {
-    Heap* heap = map->GetHeap();
-    VisitPointers(heap, object,
-                  HeapObject::RawField(object, JSFunction::kPropertiesOffset),
-                  HeapObject::RawField(object, JSFunction::kCodeEntryOffset));
-
-    // Don't visit code entry. We are using this visitor only during scavenges.
-
-    VisitPointers(
-        heap, object, HeapObject::RawField(
-                          object, JSFunction::kCodeEntryOffset + kPointerSize),
-        HeapObject::RawField(object, JSFunction::kNonWeakFieldsEndOffset));
-    return JSFunction::kSize;
+  // Although we are using the JSFunction body descriptor which does not
+  // visit the code entry, compiler wants it to be accessible.
+  // See JSFunction::BodyDescriptorImpl.
+  INLINE(static void VisitCodeEntry(Heap* heap, HeapObject* object,
+                                    Address entry_address)) {
+    UNREACHABLE();
   }
 
+ private:
   INLINE(static int VisitByteArray(Map* map, HeapObject* object)) {
     return reinterpret_cast<ByteArray*>(object)->ByteArraySize();
   }
 
   INLINE(static int VisitFixedDoubleArray(Map* map, HeapObject* object)) {
     int length = reinterpret_cast<FixedDoubleArray*>(object)->length();
     return FixedDoubleArray::SizeFor(length);
   }
 
   INLINE(static int VisitFixedTypedArray(Map* map, HeapObject* object)) {
@@ skipping 118 matching lines @@
   static void MarkOptimizedCodeMap(Heap* heap, FixedArray* code_map);
 
   // Code flushing support.
   INLINE(static bool IsFlushable(Heap* heap, JSFunction* function));
   INLINE(static bool IsFlushable(Heap* heap, SharedFunctionInfo* shared_info));
 
   // Helpers used by code flushing support that visit pointer fields and treat
   // references to code objects either strongly or weakly.
   static void VisitSharedFunctionInfoStrongCode(Heap* heap, HeapObject* object);
   static void VisitSharedFunctionInfoWeakCode(Heap* heap, HeapObject* object);
-  static void VisitJSFunctionStrongCode(Heap* heap, HeapObject* object);
-  static void VisitJSFunctionWeakCode(Heap* heap, HeapObject* object);
+  static void VisitJSFunctionStrongCode(Map* map, HeapObject* object);
+  static void VisitJSFunctionWeakCode(Map* map, HeapObject* object);
 
   class DataObjectVisitor {
    public:
     template <int size>
     static inline void VisitSpecialized(Map* map, HeapObject* object) {}
 
     INLINE(static void Visit(Map* map, HeapObject* object)) {}
   };
 
   typedef FlexibleBodyVisitor<StaticVisitor, FixedArray::BodyDescriptor, void>
@@ skipping 23 matching lines @@
 // the next element. Given the head of the list, this function removes dead
 // elements from the list and if requested records slots for next-element
 // pointers. The template parameter T is a WeakListVisitor that defines how to
 // access the next-element pointers.
 template <class T>
 Object* VisitWeakList(Heap* heap, Object* list, WeakObjectRetainer* retainer);
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_OBJECTS_VISITING_H_