Store paint properties directly on LayoutObject

third_party/WebKit/Source/core/layout/LayoutObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc.
  *               All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved.
  *               (http://www.torchmobile.com/)
@@ skipping 110 matching lines @@
   virtual ~SameSizeAsLayoutObject() {}  // Allocate vtable pointer.
   void* pointers[5];
   Member<void*> members[1];
 #if ENABLE(ASSERT)
   unsigned m_debugBitfields : 2;
 #endif
   unsigned m_bitfields;
   unsigned m_bitfields2;
   LayoutRect m_visualRect;
   LayoutPoint m_paintOffset;
+  std::unique_ptr<void*> m_paintProperties;
 };
 
 static_assert(sizeof(LayoutObject) == sizeof(SameSizeAsLayoutObject),
               "LayoutObject should stay small");
 
 bool LayoutObject::s_affectsParentBlock = false;
 
-// The pointer to paint properties is implemented as a global hash map
-// temporarily, to avoid memory regression during the transition towards SPv2.
-typedef HashMap<const LayoutObject*, std::unique_ptr<ObjectPaintProperties>>
-    PaintPropertiesMap;
-static PaintPropertiesMap& paintPropertiesMap() {
-  DEFINE_STATIC_LOCAL(PaintPropertiesMap, staticPaintPropertiesMap, ());
-  return staticPaintPropertiesMap;
-}
-
 void* LayoutObject::operator new(size_t sz) {
   ASSERT(isMainThread());
   return partitionAlloc(WTF::Partitions::layoutPartition(), sz,
                         WTF_HEAP_PROFILER_TYPE_NAME(LayoutObject));
 }
 
 void LayoutObject::operator delete(void* ptr) {
   ASSERT(isMainThread());
   partitionFree(ptr);
 }
@@ skipping 2414 matching lines @@
                 EventHandlerRegistry::TouchStartOrMoveEventBlocking)
             ->contains(node()))
       registry.didRemoveEventHandler(
           *node(), EventHandlerRegistry::TouchStartOrMoveEventBlocking);
   }
 
   setAncestorLineBoxDirty(false);
 
   ObjectPaintInvalidator::objectWillBeDestroyed(*this);
 
-  if (RuntimeEnabledFeatures::slimmingPaintV2Enabled())
-    paintPropertiesMap().remove(this);
-
   clearLayoutRootIfNeeded();
 
   if (m_style) {
     for (const FillLayer* bgLayer = &m_style->backgroundLayers(); bgLayer;
          bgLayer = bgLayer->next()) {
       if (StyleImage* backgroundImage = bgLayer->image())
         backgroundImage->removeClient(this);
     }
 
     for (const FillLayer* maskLayer = &m_style->maskLayers(); maskLayer;
@@ skipping 897 matching lines @@
   m_bitfields.setIsBackgroundAttachmentFixedObject(
       isBackgroundAttachmentFixedObject);
   if (isBackgroundAttachmentFixedObject)
     frameView()->addBackgroundAttachmentFixedObject(this);
   else
     frameView()->removeBackgroundAttachmentFixedObject(this);
 }
 
 const ObjectPaintProperties* LayoutObject::paintProperties() const {
   DCHECK(RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled());
-  return paintPropertiesMap().get(this);
+  return m_paintProperties.get();
 }
 
 ObjectPaintProperties& LayoutObject::ensurePaintProperties() {
   DCHECK(RuntimeEnabledFeatures::slimmingPaintInvalidationEnabled());
-  auto addResult = paintPropertiesMap().add(this, nullptr);
-  if (addResult.isNewEntry)
-    addResult.storedValue->value = ObjectPaintProperties::create();
-
-  return *addResult.storedValue->value;
+  if (!m_paintProperties)
+    m_paintProperties = ObjectPaintProperties::create();
+  return *m_paintProperties;
 }
 
 LayoutRect LayoutObject::debugRect() const {
   LayoutRect rect;
   LayoutBlock* block = containingBlock();
   if (block)
     block->adjustChildDebugRect(rect);
 
   return rect;
 }
@@ skipping 26 matching lines @@
     const blink::LayoutObject* root = object1;
     while (root->parent())
       root = root->parent();
     root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
   } else {
     WTFLogAlways("%s", "Cannot showLayoutTree. Root is (nil)");
   }
 }
 
 #endif