Oilpan: Schedule a precise GC when a page navigates

Source/core/dom/Document.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 1019 matching lines @@
 
     NthIndexCache* nthIndexCache() const { return m_nthIndexCache; }
 
     bool isPrivilegedContext(String& errorMessage, const PrivilegeContextCheck = StandardPrivilegeCheck) const override;
 
     void setClientHintsPreferences(const ClientHintsPreferences& preferences) { m_clientHintsPreferences.set(preferences); }
     const ClientHintsPreferences& clientHintsPreferences() const { return m_clientHintsPreferences; }
 
     CanvasFontCache* canvasFontCache();
 
+    void incrementNodeCount() { m_nodeCount++; }
+    void decrementNodeCount() { m_nodeCount--; }

[haraken, 2015/08/03 01:03:59]

I'd use 'signed int' for m_nodeCount and add ASSERT(m_nodeCount > 0) here.

[keishi, 2015/08/06 06:59:14]

Done.

+    unsigned nodeCount() { return m_nodeCount; }
+
+    using WeakDocumentSet = WillBeHeapHashSet<RawPtrWillBeWeakMember<Document>>;
+    static WeakDocumentSet& liveDocumentSet();
+
 protected:
     Document(const DocumentInit&, DocumentClassFlags = DefaultDocumentClass);
 
     void didUpdateSecurityOrigin() final;
 
     void clearXMLVersion() { m_xmlVersion = String(); }
 
 #if !ENABLE(OILPAN)
     void dispose() override;
 #endif
@@ skipping 326 matching lines @@
 
     int m_styleRecalcElementCounter;
 
     ParserSynchronizationPolicy m_parserSyncPolicy;
 
     OriginsUsingFeatures::Value m_originsUsingFeaturesValue;
 
     ClientHintsPreferences m_clientHintsPreferences;
 
     PersistentWillBeMember<CanvasFontCache> m_canvasFontCache;
+
+    unsigned m_nodeCount;
 };
 
 extern template class CORE_EXTERN_TEMPLATE_EXPORT WillBeHeapSupplement<Document>;
 
 inline bool Document::shouldOverrideLegacyDescription(ViewportDescription::Type origin)
 {
     // The different (legacy) meta tags have different priorities based on the type
     // regardless of which order they appear in the DOM. The priority is given by the
     // ViewportDescription::Type enum.
     return origin >= m_legacyViewportDescription.type;
@@ skipping 29 matching lines @@
 DEFINE_TYPE_CASTS(TreeScope, Document, document, true, true);
 
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 CORE_EXPORT void showLiveDocumentInstances();
 #endif
 
 #endif // Document_h