Move both dynamic and static object body visiting logic to BodyDescriptorBase class.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index b57e27bb40c6f3dfd6a07ddee6c7c087cf6aa2fe..8d6737b2eeb00e4919bf2ba50f9531beb4f340aa 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -7843,7 +7843,8 @@ Relocatable::~Relocatable() {
 
 
 // static
-int JSObject::BodyDescriptor::SizeOf(Map* map, HeapObject* object) {
+template <int start_offset>
+int FlexibleBodyDescriptor<start_offset>::SizeOf(Map* map, HeapObject* object) {
   return map->instance_size();
 }
 
@@ -7854,12 +7855,6 @@ int FixedArray::BodyDescriptor::SizeOf(Map* map, HeapObject* object) {
 }
 
 
-// static
-int StructBodyDescriptor::SizeOf(Map* map, HeapObject* object) {
-  return map->instance_size();
-}
-
-
 void Foreign::ForeignIterateBody(ObjectVisitor* v) {
   v->VisitExternalReference(
       reinterpret_cast<Address*>(FIELD_ADDR(this, kForeignAddressOffset)));
@@ -7916,48 +7911,54 @@ void ExternalTwoByteString::ExternalTwoByteStringIterateBody() {
 }
 
 
-static inline void IterateBodyUsingLayoutDescriptor(HeapObject* object,
-                                                    int start_offset,
-                                                    int end_offset,
-                                                    ObjectVisitor* v) {
-  DCHECK(FLAG_unbox_double_fields);
-  DCHECK(IsAligned(start_offset, kPointerSize) &&
-         IsAligned(end_offset, kPointerSize));
-
-  LayoutDescriptorHelper helper(object->map());
-  DCHECK(!helper.all_fields_tagged());
-
-  for (int offset = start_offset; offset < end_offset; offset += kPointerSize) {
-    // Visit all tagged fields.
-    if (helper.IsTagged(offset)) {
-      v->VisitPointer(HeapObject::RawField(object, offset));
-    }
-  }
-}
-
-
-template<int start_offset, int end_offset, int size>
-void FixedBodyDescriptor<start_offset, end_offset, size>::IterateBody(
-    HeapObject* obj,
-    ObjectVisitor* v) {
+void BodyDescriptorBase::IterateBodyImpl(HeapObject* obj, int start_offset,
+                                         int end_offset, ObjectVisitor* v) {
   if (!FLAG_unbox_double_fields || obj->map()->HasFastPointerLayout()) {
     v->VisitPointers(HeapObject::RawField(obj, start_offset),
                      HeapObject::RawField(obj, end_offset));
   } else {
-    IterateBodyUsingLayoutDescriptor(obj, start_offset, end_offset, v);
+    DCHECK(FLAG_unbox_double_fields);
+    DCHECK(IsAligned(start_offset, kPointerSize) &&
+           IsAligned(end_offset, kPointerSize));
+
+    LayoutDescriptorHelper helper(obj->map());
+    DCHECK(!helper.all_fields_tagged());
+    for (int offset = start_offset; offset < end_offset;) {
+      int end_of_region_offset;
+      if (helper.IsTagged(offset, end_offset, &end_of_region_offset)) {
+        v->VisitPointers(HeapObject::RawField(obj, offset),
+                         HeapObject::RawField(obj, end_of_region_offset));
+      }
+      offset = end_of_region_offset;
+    }
   }
 }
 
 
-template<int start_offset>
-void FlexibleBodyDescriptor<start_offset>::IterateBody(HeapObject* obj,
-                                                       int object_size,
-                                                       ObjectVisitor* v) {
+template <typename StaticVisitor>
+void BodyDescriptorBase::IterateBodyImpl(HeapObject* obj, int start_offset,
+                                         int end_offset) {
+  Heap* heap = obj->GetHeap();
   if (!FLAG_unbox_double_fields || obj->map()->HasFastPointerLayout()) {
-    v->VisitPointers(HeapObject::RawField(obj, start_offset),
-                     HeapObject::RawField(obj, object_size));
+    StaticVisitor::VisitPointers(heap, obj,
+                                 HeapObject::RawField(obj, start_offset),
+                                 HeapObject::RawField(obj, end_offset));
   } else {
-    IterateBodyUsingLayoutDescriptor(obj, start_offset, object_size, v);
+    DCHECK(FLAG_unbox_double_fields);
+    DCHECK(IsAligned(start_offset, kPointerSize) &&
+           IsAligned(end_offset, kPointerSize));
+
+    LayoutDescriptorHelper helper(obj->map());
+    DCHECK(!helper.all_fields_tagged());
+    for (int offset = start_offset; offset < end_offset;) {
+      int end_of_region_offset;
+      if (helper.IsTagged(offset, end_offset, &end_of_region_offset)) {
+        StaticVisitor::VisitPointers(
+            heap, obj, HeapObject::RawField(obj, offset),
+            HeapObject::RawField(obj, end_of_region_offset));
+      }
+      offset = end_of_region_offset;
+    }
   }
 }