Blink-side contiguous allocation of display items.

Source/core/paint/BoxClipper.cpp

 // Copyright 2014 The Chromium 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 "config.h"
 #include "core/paint/BoxClipper.h"
 
 #include "core/layout/LayoutBox.h"
 #include "core/paint/DeprecatedPaintLayer.h"
 #include "core/paint/PaintInfo.h"
@@ skipping 34 matching lines @@
         LayoutRect conservativeClipRect = clipRect;
         if (hasBorderRadius)
             conservativeClipRect.intersect(LayoutRect(clipRoundedRect.radiusCenterRect()));
         conservativeClipRect.moveBy(-m_accumulatedOffset);
         if (m_box.hasLayer())
             conservativeClipRect.move(m_box.scrolledContentOffset());
         if (conservativeClipRect.contains(contentsVisualOverflow))
             return;
     }
 
-    if (RuntimeEnabledFeatures::slimmingPaintEnabled())
-        m_clipType = m_paintInfo.displayItemTypeForClipping();
-
-    OwnPtr<ClipDisplayItem> clipDisplayItem = ClipDisplayItem::create(m_box, m_clipType, pixelSnappedIntRect(clipRect));
-    if (hasBorderRadius)
-        clipDisplayItem->roundedRectClips().append(clipRoundedRect);
-
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         ASSERT(m_paintInfo.context->displayItemList());
-        if (!m_paintInfo.context->displayItemList()->displayItemConstructionIsDisabled())
-            m_paintInfo.context->displayItemList()->add(clipDisplayItem.release());
+        m_clipType = m_paintInfo.displayItemTypeForClipping();
+        if (!m_paintInfo.context->displayItemList()->displayItemConstructionIsDisabled()) {
+            if (hasBorderRadius)
+                m_paintInfo.context->displayItemList()->createAndAppendIfNeeded<ClipDisplayItem>(m_box, m_clipType, pixelSnappedIntRect(clipRect), clipRoundedRect);
+            else
+                m_paintInfo.context->displayItemList()->createAndAppendIfNeeded<ClipDisplayItem>(m_box, m_clipType, pixelSnappedIntRect(clipRect));
+        }
     } else {
-        clipDisplayItem->replay(*paintInfo.context);
+        if (hasBorderRadius) {
+            ClipDisplayItem clipDisplayItem(m_box, m_clipType, pixelSnappedIntRect(clipRect), clipRoundedRect);
+            clipDisplayItem.replay(*paintInfo.context);
+        } else {
+            ClipDisplayItem clipDisplayItem(m_box, m_clipType, pixelSnappedIntRect(clipRect));
+            clipDisplayItem.replay(*paintInfo.context);
+        }
     }
 
     m_pushedClip = true;
 }
 
 BoxClipper::~BoxClipper()
 {
     if (!m_pushedClip)
         return;
 
     ASSERT(m_box.hasControlClip() || (m_box.hasOverflowClip() && !m_box.layer()->isSelfPaintingLayer()));
 
     DisplayItem::Type endType = DisplayItem::clipTypeToEndClipType(m_clipType);
     if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
         if (m_paintInfo.context->displayItemList()->displayItemConstructionIsDisabled())
             return;
-        OwnPtr<EndClipDisplayItem> endClipDisplayItem = EndClipDisplayItem::create(m_box, endType);
         ASSERT(m_paintInfo.context->displayItemList());
-        m_paintInfo.context->displayItemList()->add(endClipDisplayItem.release());
+        m_paintInfo.context->displayItemList()->createAndAppendIfNeeded<EndClipDisplayItem>(m_box, endType);
     } else {
         EndClipDisplayItem endClipDisplayItem(m_box, endType);
         endClipDisplayItem.replay(*m_paintInfo.context);
     }
 }
 
 } // namespace blink