two pass phantom collection

src/debug.cc

 // 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.
 
 #include "src/v8.h"
 
 #include "src/api.h"
 #include "src/arguments.h"
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
@@ skipping 575 matching lines @@
   HashMap::Entry* entry = script_cache->Lookup(key, hash, false);
   Object** location = reinterpret_cast<Object**>(entry->value);
   script_cache->Remove(key, hash);
 
   // Clear the weak handle.
   GlobalHandles::Destroy(location);
 }
 
 
 void Debug::HandlePhantomDebugInfo(
-    const v8::PhantomCallbackData<DebugInfoListNode>& data) {
+    const v8::WeakCallbackInfo<DebugInfoListNode>& data) {
+  DebugInfoListNode* node = data.GetParameter();
+  node->ClearInfo();
   Debug* debug = reinterpret_cast<Isolate*>(data.GetIsolate())->debug();
-  DebugInfoListNode* node = data.GetParameter();
   debug->RemoveDebugInfo(node);
 #ifdef DEBUG
   for (DebugInfoListNode* n = debug->debug_info_list_;
        n != NULL;
        n = n->next()) {
     DCHECK(n != node);
   }
 #endif
 }
 
 
 DebugInfoListNode::DebugInfoListNode(DebugInfo* debug_info): next_(NULL) {
   // Globalize the request debug info object and make it weak.
   GlobalHandles* global_handles = debug_info->GetIsolate()->global_handles();
-  debug_info_ = Handle<DebugInfo>::cast(global_handles->Create(debug_info));
-  typedef PhantomCallbackData<void>::Callback Callback;
+  debug_info_ =
+      Handle<DebugInfo>::cast(global_handles->Create(debug_info)).location();
+  typedef WeakCallbackInfo<void>::Callback Callback;
   GlobalHandles::MakeWeak(
-      reinterpret_cast<Object**>(debug_info_.location()), this,
+      reinterpret_cast<Object**>(debug_info_), this,
       reinterpret_cast<Callback>(Debug::HandlePhantomDebugInfo),
       v8::WeakCallbackType::kParameter);
 }
 
 
-DebugInfoListNode::~DebugInfoListNode() {
-  GlobalHandles::Destroy(reinterpret_cast<Object**>(debug_info_.location()));
+void DebugInfoListNode::ClearInfo() {
+  if (debug_info_ == nullptr) return;
+  GlobalHandles::Destroy(reinterpret_cast<Object**>(debug_info_));
+  debug_info_ = nullptr;
 }
 
 
 bool Debug::CompileDebuggerScript(Isolate* isolate, int index) {
   Factory* factory = isolate->factory();
   HandleScope scope(isolate);
 
   // Bail out if the index is invalid.
   if (index == -1) return false;
 
@@ skipping 2762 matching lines @@
   logger_->DebugEvent("Put", message.text());
 }
 
 
 void LockingCommandMessageQueue::Clear() {
   base::LockGuard<base::Mutex> lock_guard(&mutex_);
   queue_.Clear();
 }
 
 } }  // namespace v8::internal