Reland "Remove the weak list of array buffers"

src/heap/objects-visiting.cc

 // Copyright 2011 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/v8.h"
 
 #include "src/heap/objects-visiting.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 173 matching lines @@
   return heap->gc_state() == Heap::MARK_COMPACT &&
          heap->mark_compact_collector()->is_compacting();
 }
 
 
 template <class T>
 struct WeakListVisitor;
 
 
 template <class T>
-Object* VisitWeakList(Heap* heap, Object* list, WeakObjectRetainer* retainer,
-                      bool stop_after_young, Object** list_tail) {
+Object* VisitWeakList(Heap* heap, Object* list, WeakObjectRetainer* retainer) {
   Object* undefined = heap->undefined_value();
   Object* head = undefined;
   T* tail = NULL;
   MarkCompactCollector* collector = heap->mark_compact_collector();
   bool record_slots = MustRecordSlots(heap);
 
   while (list != undefined) {
     // Check whether to keep the candidate in the list.
     T* candidate = reinterpret_cast<T*>(list);
 
@@ skipping 22 matching lines @@
 
     } else {
       WeakListVisitor<T>::VisitPhantomObject(heap, candidate);
     }
 
     // Move to next element in the list.
     list = WeakListVisitor<T>::WeakNext(candidate);
   }
 
   // Terminate the list if there is one or more elements.
-  if (tail != NULL) {
-    WeakListVisitor<T>::SetWeakNext(tail, undefined);
-    if (list_tail) *list_tail = tail;
-  }
+  if (tail != NULL) WeakListVisitor<T>::SetWeakNext(tail, undefined);
   return head;
 }
 
 
 template <class T>
 static void ClearWeakList(Heap* heap, Object* list) {
   Object* undefined = heap->undefined_value();
   while (list != undefined) {
     T* candidate = reinterpret_cast<T*>(list);
     list = WeakListVisitor<T>::WeakNext(candidate);
@@ skipping 61 matching lines @@
     if (heap->gc_state() == Heap::MARK_COMPACT) {
       DoWeakList<Code>(heap, context, retainer, Context::OPTIMIZED_CODE_LIST);
       DoWeakList<Code>(heap, context, retainer, Context::DEOPTIMIZED_CODE_LIST);
     }
   }
 
   template <class T>
   static void DoWeakList(Heap* heap, Context* context,
                          WeakObjectRetainer* retainer, int index) {
     // Visit the weak list, removing dead intermediate elements.
-    Object* list_head =
-        VisitWeakList<T>(heap, context->get(index), retainer, false, NULL);
+    Object* list_head = VisitWeakList<T>(heap, context->get(index), retainer);
 
     // Update the list head.
     context->set(index, list_head, UPDATE_WRITE_BARRIER);
 
     if (MustRecordSlots(heap)) {
       // Record the updated slot if necessary.
       Object** head_slot =
           HeapObject::RawField(context, FixedArray::SizeFor(index));
       heap->mark_compact_collector()->RecordSlot(head_slot, head_slot,
                                                  list_head);
     }
   }
 
   static void VisitPhantomObject(Heap* heap, Context* context) {
     ClearWeakList<JSFunction>(heap,
                               context->get(Context::OPTIMIZED_FUNCTIONS_LIST));
     ClearWeakList<Code>(heap, context->get(Context::OPTIMIZED_CODE_LIST));
     ClearWeakList<Code>(heap, context->get(Context::DEOPTIMIZED_CODE_LIST));
   }
 };
 
 
 template <>
-struct WeakListVisitor<JSArrayBuffer> {
-  static void SetWeakNext(JSArrayBuffer* obj, Object* next) {
-    obj->set_weak_next(next);
-  }
-
-  static Object* WeakNext(JSArrayBuffer* obj) { return obj->weak_next(); }
-
-  static int WeakNextOffset() { return JSArrayBuffer::kWeakNextOffset; }
-
-  static void VisitLiveObject(Heap* heap, JSArrayBuffer* array_buffer,
-                              WeakObjectRetainer* retainer) {
-  }
-
-  static void VisitPhantomObject(Heap* heap, JSArrayBuffer* phantom) {
-    Runtime::FreeArrayBuffer(heap->isolate(), phantom);
-  }
-};
-
-
-template <>
 struct WeakListVisitor<AllocationSite> {
   static void SetWeakNext(AllocationSite* obj, Object* next) {
     obj->set_weak_next(next);
   }
 
   static Object* WeakNext(AllocationSite* obj) { return obj->weak_next(); }
 
   static int WeakNextOffset() { return AllocationSite::kWeakNextOffset; }
 
   static void VisitLiveObject(Heap*, AllocationSite*, WeakObjectRetainer*) {}
 
   static void VisitPhantomObject(Heap*, AllocationSite*) {}
 };
 
 
 template Object* VisitWeakList<Context>(Heap* heap, Object* list,
-                                        WeakObjectRetainer* retainer,
-                                        bool stop_after_young,
-                                        Object** list_tail);
-
-
-template Object* VisitWeakList<JSArrayBuffer>(Heap* heap, Object* list,
-                                              WeakObjectRetainer* retainer,
-                                              bool stop_after_young,
-                                              Object** list_tail);
+                                        WeakObjectRetainer* retainer);
 
 template Object* VisitWeakList<AllocationSite>(Heap* heap, Object* list,
-                                               WeakObjectRetainer* retainer,
-                                               bool stop_after_young,
-                                               Object** list_tail);
+                                               WeakObjectRetainer* retainer);
 }
 }  // namespace v8::internal