Oilpan: move 2D Canvas and WebGL objects to the heap.

Source/core/html/canvas/WebGLContextGroup.cpp

 /*
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 13 matching lines @@
  */
 
 #include "config.h"
 
 #include "core/html/canvas/WebGLContextGroup.h"
 
 #include "core/html/canvas/WebGLSharedObject.h"
 
 namespace WebCore {
 
-PassRefPtr<WebGLContextGroup> WebGLContextGroup::create()
+PassRefPtrWillBeRawPtr<WebGLContextGroup> WebGLContextGroup::create()
 {
-    RefPtr<WebGLContextGroup> contextGroup = adoptRef(new WebGLContextGroup());
+    RefPtrWillBeRawPtr<WebGLContextGroup> contextGroup = adoptRefWillBeNoop(new WebGLContextGroup());
     return contextGroup.release();
 }
 
 WebGLContextGroup::WebGLContextGroup()
+#if ENABLE(OILPAN)
+    : m_savedContext(0)
+#endif
 {
 }
 
+#if !ENABLE(OILPAN)
 WebGLContextGroup::~WebGLContextGroup()
 {
     detachAndRemoveAllObjects();
 }
+#endif
 
 blink::WebGraphicsContext3D* WebGLContextGroup::getAWebGraphicsContext3D()
 {
+#if ENABLE(OILPAN)
+    ASSERT(!m_contexts.isEmpty() || m_savedContext);
+    if (m_savedContext)
+        return m_savedContext;
+#else
     ASSERT(!m_contexts.isEmpty());
-    HashSet<WebGLRenderingContextBase*>::iterator it = m_contexts.begin();
+#endif
+    WillBeHeapHashSet<RawPtrWillBeWeakMember<WebGLRenderingContextBase> >::iterator it = m_contexts.begin();
     return (*it)->webContext();
 }
 
 void WebGLContextGroup::addContext(WebGLRenderingContextBase* context)
 {
     m_contexts.add(context);
 }
 
 void WebGLContextGroup::removeContext(WebGLRenderingContextBase* context)
 {
     // We must call detachAndRemoveAllObjects before removing the last context.
     if (m_contexts.size() == 1 && m_contexts.contains(context))
         detachAndRemoveAllObjects();
 
     m_contexts.remove(context);
 }
 
 void WebGLContextGroup::removeObject(WebGLSharedObject* object)
 {
+#if ENABLE(OILPAN)
+    // Oilpan: if removal happens during weak callback processing, ignore.
+    // Done so as to prevent re-allocation of the backing store; the table
+    // is cleared afterwards instead.
+    if (m_savedContext)
+        return;
+#endif
     m_groupObjects.remove(object);
 }
 
 void WebGLContextGroup::addObject(WebGLSharedObject* object)
 {
     m_groupObjects.add(object);
 }
 
 void WebGLContextGroup::detachAndRemoveAllObjects()
 {
     while (!m_groupObjects.isEmpty()) {
-        HashSet<WebGLSharedObject*>::iterator it = m_groupObjects.begin();
+        WillBeHeapHashSet<RawPtrWillBeWeakMember<WebGLSharedObject> >::iterator it = m_groupObjects.begin();
         (*it)->detachContextGroup();
     }
 }
 
 void WebGLContextGroup::loseContextGroup(WebGLRenderingContextBase::LostContextMode mode)
 {
     // Detach must happen before loseContextImpl, which destroys the GraphicsContext3D
     // and prevents groupObjects from being properly deleted.
     detachAndRemoveAllObjects();
 
-    for (HashSet<WebGLRenderingContextBase*>::iterator it = m_contexts.begin(); it != m_contexts.end(); ++it)
+    for (WillBeHeapHashSet<RawPtrWillBeWeakMember<WebGLRenderingContextBase> >::iterator it = m_contexts.begin(); it != m_contexts.end(); ++it)
         (*it)->loseContextImpl(mode);
 }
 
+void WebGLContextGroup::clearWeakMembers(Visitor*)
+{
+#if ENABLE(OILPAN)
+    // We must call detachAndRemoveAllObjects when there are no contexts left.
+    // In order to be able to provide the group objects with the WebGraphicsContext3D
+    // object they need on detach, one is saved away during tracing.
+    if (!m_contexts.size() && m_savedContext) {
+        detachAndRemoveAllObjects();
+        m_groupObjects.clear();
+    }
+    m_savedContext = 0;
+#endif
+}
+
+void WebGLContextGroup::trace(Visitor* visitor)
+{
+#if ENABLE(OILPAN)
+    // See clearWeakMembers() comment.
+    if (m_contexts.size() && m_groupObjects.size()) {
+        m_savedContext = getAWebGraphicsContext3D();
+        ASSERT(m_savedContext);
+    }
+#endif
+    visitor->trace(m_contexts);
+    visitor->trace(m_groupObjects);
+    visitor->registerWeakMembers<WebGLContextGroup, &WebGLContextGroup::clearWeakMembers>(this);
+}
+
 } // namespace WebCore