Refactor ResourceLoadPriorityOptimizer to avoid walking render tree

Source/core/rendering/RenderBlock.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 164 matching lines @@
             ASSERT(containerSet->contains(block));
             containerSet->remove(block);
             if (containerSet->isEmpty())
                 containerMap->remove(it);
         }
     }
 }
 
 static void appendImageIfNotNull(Vector<ImageResource*>& imageResources, const StyleImage* styleImage)
 {
-    if (styleImage && styleImage->cachedImage())
-        imageResources.append(styleImage->cachedImage());
+    if (styleImage && styleImage->cachedImage()) {
+        ImageResource* imageResource = styleImage->cachedImage();
+        if (imageResource && !imageResource->isLoaded())
+            imageResources.append(styleImage->cachedImage());
+    }
 }
 
 static void appendLayers(Vector<ImageResource*>& images, const FillLayer* styleLayer)
 {
     for (const FillLayer* layer = styleLayer; layer; layer = layer->next()) {
         appendImageIfNotNull(images, layer->image());
     }
 }
 
+static void appendImagesFromStyle(Vector<ImageResource*>& images, RenderStyle* blockStyle)

[esprehn, 2014/01/15 01:27:45]

RenerStyle& blockStyle

[shatch, 2014/01/15 19:28:52]

Done.

+{
+    appendLayers(images, blockStyle->backgroundLayers());
+    appendLayers(images, blockStyle->maskLayers());
+
+    const ContentData* contentData = blockStyle->contentData();
+    if (contentData && contentData->isImage()) {
+        const ImageContentData* imageContentData = static_cast<const ImageContentData*>(contentData);
+        appendImageIfNotNull(images, imageContentData->image());
+    }
+    if (blockStyle->boxReflect())
+        appendImageIfNotNull(images, blockStyle->boxReflect()->mask().image());
+    appendImageIfNotNull(images, blockStyle->listStyleImage());
+    appendImageIfNotNull(images, blockStyle->borderImageSource());
+    appendImageIfNotNull(images, blockStyle->maskBoxImageSource());
+}
+
 RenderBlock::~RenderBlock()
 {
+    resourceLoadPriorityOptimizer()->removeRenderObject(this);
     if (hasColumns())
         gColumnInfoMap->take(this);
     if (gPercentHeightDescendantsMap)
         removeBlockFromDescendantAndContainerMaps(this, gPercentHeightDescendantsMap, gPercentHeightContainerMap);
     if (gPositionedDescendantsMap)
         removeBlockFromDescendantAndContainerMaps(this, gPositionedDescendantsMap, gPositionedContainerMap);
 }
 
 void RenderBlock::willBeDestroyed()
 {
@@ skipping 111 matching lines @@
 
     if (FastTextAutosizer* textAutosizer = document().fastTextAutosizer())
         textAutosizer->record(this);
 
     propagateStyleToAnonymousChildren(true);
     m_lineHeight = -1;
 
     // It's possible for our border/padding to change, but for the overall logical width of the block to
     // end up being the same. We keep track of this change so in layoutBlock, we can know to set relayoutChildren=true.
     m_hasBorderOrPaddingLogicalWidthChanged = oldStyle && diff == StyleDifferenceLayout && needsLayout() && borderOrPaddingLogicalWidthChanged(oldStyle, newStyle);
+
+    // If the style has unloaded images, want to notify the ResourceLoadPriorityOptimizer so that
+    // network priorities can be set.
+    Vector<ImageResource*> images;
+    appendImagesFromStyle(images, newStyle);
+    if (images.isEmpty())
+        resourceLoadPriorityOptimizer()->removeRenderObject(this);

[esprehn, 2014/01/15 01:27:45]

This isn't good, you're going to hit the hash table in the remove() call all the
time, usually we use a bit to avoid this. I'd add a bit for tracking if this
renderer is actually in that hash table.

addRenderObject does renderer->setHasPendingResourceUpdate() or something like
that.
removeRenderObject does:
if (!renderer->hasPendingResourceUpdate())
  return;
m_objects.remove(renderer);
renderer->setHasPendingResourcesUpdate(false);

[shatch, 2014/01/15 19:28:52]

Done.

+    else
+        resourceLoadPriorityOptimizer()->addRenderObject(this);
 }
 
 RenderBlock* RenderBlock::continuationBefore(RenderObject* beforeChild)
 {
     if (beforeChild && beforeChild->parent() == this)
         return this;
 
     RenderBlock* curr = toRenderBlock(continuation());
     RenderBlock* nextToLast = this;
     RenderBlock* last = this;
@@ skipping 920 matching lines @@
         return;
 
     // It's safe to check for control clip here, since controls can never be table cells.
     // If we have a lightweight clip, there can never be any overflow from children.
     if (hasControlClip() && m_overflow)
         clearLayoutOverflow();
 
     invalidateBackgroundObscurationStatus();
 }
 
-void RenderBlock::didLayout(ResourceLoadPriorityOptimizer& optimizer)
+bool RenderBlock::updateImageLoadingPriorities()
 {
-    RenderBox::didLayout(optimizer);
-    updateStyleImageLoadingPriorities(optimizer);
-}
-
-void RenderBlock::didScroll(ResourceLoadPriorityOptimizer& optimizer)
-{
-    RenderBox::didScroll(optimizer);
-    updateStyleImageLoadingPriorities(optimizer);
-}
-
-void RenderBlock::updateStyleImageLoadingPriorities(ResourceLoadPriorityOptimizer& optimizer)
-{
-    RenderStyle* blockStyle = style();
-    if (!blockStyle)
-        return;
-
     Vector<ImageResource*> images;
-
-    appendLayers(images, blockStyle->backgroundLayers());
-    appendLayers(images, blockStyle->maskLayers());
-
-    const ContentData* contentData = blockStyle->contentData();
-    if (contentData && contentData->isImage()) {
-        const ImageContentData* imageContentData = static_cast<const ImageContentData*>(contentData);
-        appendImageIfNotNull(images, imageContentData->image());
-    }
-    if (blockStyle->boxReflect())
-        appendImageIfNotNull(images, blockStyle->boxReflect()->mask().image());
-    appendImageIfNotNull(images, blockStyle->listStyleImage());
-    appendImageIfNotNull(images, blockStyle->borderImageSource());
-    appendImageIfNotNull(images, blockStyle->maskBoxImageSource());
+    appendImagesFromStyle(images, style());
 
     if (images.isEmpty())
-        return;
+        return false;
 
     LayoutRect viewBounds = viewRect();
     LayoutRect objectBounds = absoluteContentBox();
     // The object bounds might be empty right now, so intersects will fail since it doesn't deal
     // with empty rects. Use LayoutRect::contains in that case.
     bool isVisible;
     if (!objectBounds.isEmpty())
         isVisible =  viewBounds.intersects(objectBounds);
     else
         isVisible = viewBounds.contains(objectBounds);
 
     ResourceLoadPriorityOptimizer::VisibilityStatus status = isVisible ?
         ResourceLoadPriorityOptimizer::Visible : ResourceLoadPriorityOptimizer::NotVisible;
 
     for (Vector<ImageResource*>::iterator it = images.begin(), end = images.end(); it != end; ++it)
-        optimizer.notifyImageResourceVisibility(*it, status);
+        resourceLoadPriorityOptimizer()->notifyImageResourceVisibility(*it, status);
+
+    return true;
 }
 
 void RenderBlock::relayoutShapeDescendantIfMoved(RenderBlock* child, LayoutSize offset)
 {
     LayoutUnit left = isHorizontalWritingMode() ? offset.width() : offset.height();
     if (!left || !child || child->shapeInsideInfo() || !layoutShapeInsideInfo())
         return;
     // Propagate layout markers only up to the child, as we are still in the middle
     // of a layout pass
     child->setNormalChildNeedsLayout(true);
@@ skipping 4339 matching lines @@
 void RenderBlock::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj) const
 {
     showRenderObject();
     for (const RootInlineBox* root = firstRootBox(); root; root = root->nextRootBox())
         root->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, 1);
 }
 
 #endif
 
 } // namespace WebCore