Output subsequence for children layers

third_party/WebKit/Source/platform/graphics/paint/DisplayItemList.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 "platform/graphics/paint/DisplayItemList.h"
 
 #include "platform/NotImplemented.h"
 #include "platform/TraceEvent.h"
 #include "platform/graphics/paint/DrawingDisplayItem.h"
@@ skipping 43 matching lines @@
     ASSERT(!m_constructionDisabled);
     ASSERT(!skippingCache() || !displayItem.isCached());
 
     if (displayItem.isCached())
         ++m_numCachedItems;
 
 #if ENABLE(ASSERT)
     // Verify noop begin/end pairs have been removed.
     if (m_newDisplayItems.size() >= 2 && displayItem.isEnd()) {
         const auto& beginDisplayItem = m_newDisplayItems[m_newDisplayItems.size() - 2];
-        if (beginDisplayItem.isBegin() && beginDisplayItem.type() != DisplayItem::BeginSubsequence && !beginDisplayItem.drawsContent())
+        if (beginDisplayItem.isBegin() && !beginDisplayItem.isSubsequence() && !beginDisplayItem.drawsContent())
             ASSERT(!displayItem.isEndAndPairedWith(beginDisplayItem.type()));
     }
 #endif
 
     if (!m_scopeStack.isEmpty())
         displayItem.setScope(m_scopeStack.last());
 
 #if ENABLE(ASSERT)
     size_t index = findMatchingItemFromIndex(displayItem.nonCachedId(), m_newDisplayItemIndicesByClient, m_newDisplayItems);
     if (index != kNotFound) {
@@ skipping 146 matching lines @@
                 return context.nextItemToIndex++;
 
             addItemToIndexIfNeeded(item, context.nextItemToIndex - m_currentDisplayItems.begin(), context.displayItemIndicesByClient);
         }
     }
     return currentEnd;
 }
 
 void DisplayItemList::copyCachedSubsequence(DisplayItems::iterator& currentIt, DisplayItems& updatedList)
 {
-    ASSERT(currentIt->type() == DisplayItem::BeginSubsequence);
+    ASSERT(currentIt->isSubsequence());
     ASSERT(!currentIt->scope());
-    DisplayItem::Id endSubsequenceId(currentIt->client(), DisplayItem::EndSubsequence, 0);
+    DisplayItem::Id endSubsequenceId(currentIt->client(), DisplayItem::subsequenceTypeToEndSubsequenceType(currentIt->type()), 0);
     do {
         // We should always find the EndSubsequence display item.
         ASSERT(currentIt != m_currentDisplayItems.end());
         ASSERT(currentIt->isValid());
         updatedList.appendByMoving(*currentIt);
         ++currentIt;
     } while (!endSubsequenceId.matches(updatedList.last()));
 }
 
 // Update the existing display items by removing invalidated entries, updating
 // repainted ones, and appending new items.
-// - For CachedDisplayItem, copy the corresponding cached DrawingDisplayItem;
-// - For SubsequenceCachedDisplayItem, copy the cached display items between the
-//   corresponding BeginSubsequenceDisplayItem and EndSubsequenceDisplayItem (incl.);
+// - For cached drawing display item, copy the corresponding cached DrawingDisplayItem;
+// - For cached subsequence display item, copy the cached display items between the
+//   corresponding SubsequenceDisplayItem and EndSubsequenceDisplayItem (incl.);
 // - Otherwise, copy the new display item.
 //
 // The algorithm is O(|m_currentDisplayItems| + |m_newDisplayItems|).
-// Coefficients are related to the ratio of out-of-order [Subsequence]CachedDisplayItems
-// and the average number of (Drawing|BeginSubsequence)DisplayItems per client.
+// Coefficients are related to the ratio of out-of-order CachedDisplayItems
+// and the average number of (Drawing|Subsequence)DisplayItems per client.
 //
 // TODO(pdr): Implement the DisplayListDiff algorithm for SlimmingPaintV2.
 void DisplayItemList::commitNewDisplayItems(DisplayListDiff*)
 {
     TRACE_EVENT2("blink,benchmark", "DisplayItemList::commitNewDisplayItems", "current_display_list_size", (int)m_currentDisplayItems.size(),
         "num_non_cached_new_items", (int)m_newDisplayItems.size() - m_numCachedItems);
 
     // These data structures are used during painting only.
     ASSERT(m_scopeStack.isEmpty());
     m_scopeStack.clear();
@@ skipping 55 matching lines @@
 #if ENABLE(ASSERT)
             if (RuntimeEnabledFeatures::slimmingPaintUnderInvalidationCheckingEnabled()) {
                 DisplayItems::iterator temp = currentIt;
                 checkUnderInvalidation(newIt, temp);
             }
 #endif
             if (newDisplayItem.isCachedDrawing()) {
                 updatedList.appendByMoving(*currentIt);
                 ++currentIt;
             } else {
-                ASSERT(newDisplayItem.type() == DisplayItem::CachedSubsequence);
+                ASSERT(newDisplayItem.isCachedSubsequence());
                 copyCachedSubsequence(currentIt, updatedList);
-                ASSERT(updatedList.last().type() == DisplayItem::EndSubsequence);
+                ASSERT(updatedList.last().isEndSubsequence());
             }
         } else {
             ASSERT(!newDisplayItem.isDrawing()
                 || newDisplayItem.skippedCache()
                 || !clientCacheIsValid(newDisplayItem.client())
                 || (RuntimeEnabledFeatures::slimmingPaintOffsetCachingEnabled() && paintOffsetWasInvalidated(newDisplayItem.client())));
 
             updatedList.appendByMoving(*newIt);
 
             if (isSynchronized)
@@ skipping 85 matching lines @@
     // When under-invalidation-checking is enabled, the forced painting is following the cached display item.
     DisplayItem::Type nextItemType = DisplayItem::nonCachedType(newIt->type());
     ++newIt;
     ASSERT(newIt->type() == nextItemType);
 
     if (newIt->isDrawing()) {
         checkCachedDisplayItemIsUnchanged("", *newIt, *currentIt);
         return;
     }
 
-    ASSERT(newIt->type() == DisplayItem::BeginSubsequence);
+    ASSERT(newIt->isSubsequence());
 
 #ifndef NDEBUG
     CString messagePrefix = String::format("(In CachedSubsequence of %s)", newIt->clientDebugString().utf8().data()).utf8();
 #else
     CString messagePrefix = "(In CachedSubsequence)";
 #endif
 
-    DisplayItem::Id endSubsequenceId(newIt->client(), DisplayItem::EndSubsequence, 0);
+    DisplayItem::Id endSubsequenceId(newIt->client(), DisplayItem::subsequenceTypeToEndSubsequenceType(newIt->type()), 0);
     while (true) {
         ASSERT(newIt != m_newDisplayItems.end());
         if (newIt->isCached())
             checkUnderInvalidation(newIt, currentIt);
         else
             checkCachedDisplayItemIsUnchanged(messagePrefix.data(), *newIt, *currentIt);
 
         if (endSubsequenceId.matches(*newIt))
             break;
 
@@ skipping 92 matching lines @@
 
 void DisplayItemList::replay(GraphicsContext& context)
 {
     TRACE_EVENT0("blink,benchmark", "DisplayItemList::replay");
     ASSERT(m_newDisplayItems.isEmpty());
     for (DisplayItem& displayItem : m_currentDisplayItems)
         displayItem.replay(context);
 }
 
 } // namespace blink