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<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/181247">181247</a></dd>
<dt>Author</dt> <dd>simon.fraser@apple.com</dd>
<dt>Date</dt> <dd>2015-03-08 16:39:16 -0700 (Sun, 08 Mar 2015)</dd>
</dl>
<h3>Log Message</h3>
<pre>Don't call RenderLayerCompositor::needsToBeComposited() so many times
https://bugs.webkit.org/show_bug.cgi?id=142441
Reviewed by Brent Fulgham.
Save one call to needsToBeComposited() per RenderLayer while rebuilding compositing
layers, and a call to isRunningAcceleratedTransformAnimation() in some cases.
computeCompositingRequirements() already knows if the layer will be composited, so
pass that to updateBacking() in the form of a "yes/no/don't" know enum. However,
since updateBacking() no longer calls needsToBeComposited(), we need to call
requiresCompositingForPosition() to get the viewportConstrainedNotCompositedReason flags.
isRunningAcceleratedTransformAnimation() will only be true for a layer which has a
direct compositing reason, so only call isRunningAcceleratedTransformAnimation()
in that case.
* rendering/RenderLayerCompositor.cpp:
(WebCore::rendererForCompositingTests):
(WebCore::RenderLayerCompositor::updateBacking):
(WebCore::RenderLayerCompositor::computeCompositingRequirements):
(WebCore::RenderLayerCompositor::requiresCompositingLayer): Use references.
(WebCore::RenderLayerCompositor::reasonsForCompositing): Use references.
* rendering/RenderLayerCompositor.h:</pre>
<h3>Modified Paths</h3>
<ul>
<li><a href="#trunkSourceWebCoreChangeLog">trunk/Source/WebCore/ChangeLog</a></li>
<li><a href="#trunkSourceWebCorerenderingRenderLayerCompositorcpp">trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp</a></li>
<li><a href="#trunkSourceWebCorerenderingRenderLayerCompositorh">trunk/Source/WebCore/rendering/RenderLayerCompositor.h</a></li>
</ul>
</div>
<div id="patch">
<h3>Diff</h3>
<a id="trunkSourceWebCoreChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/ChangeLog (181246 => 181247)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/ChangeLog 2015-03-08 21:32:50 UTC (rev 181246)
+++ trunk/Source/WebCore/ChangeLog 2015-03-08 23:39:16 UTC (rev 181247)
</span><span class="lines">@@ -1,5 +1,32 @@
</span><span class="cx"> 2015-03-08 Simon Fraser <simon.fraser@apple.com>
</span><span class="cx">
</span><ins>+ Don't call RenderLayerCompositor::needsToBeComposited() so many times
+ https://bugs.webkit.org/show_bug.cgi?id=142441
+
+ Reviewed by Brent Fulgham.
+
+ Save one call to needsToBeComposited() per RenderLayer while rebuilding compositing
+ layers, and a call to isRunningAcceleratedTransformAnimation() in some cases.
+
+ computeCompositingRequirements() already knows if the layer will be composited, so
+ pass that to updateBacking() in the form of a "yes/no/don't" know enum. However,
+ since updateBacking() no longer calls needsToBeComposited(), we need to call
+ requiresCompositingForPosition() to get the viewportConstrainedNotCompositedReason flags.
+
+ isRunningAcceleratedTransformAnimation() will only be true for a layer which has a
+ direct compositing reason, so only call isRunningAcceleratedTransformAnimation()
+ in that case.
+
+ * rendering/RenderLayerCompositor.cpp:
+ (WebCore::rendererForCompositingTests):
+ (WebCore::RenderLayerCompositor::updateBacking):
+ (WebCore::RenderLayerCompositor::computeCompositingRequirements):
+ (WebCore::RenderLayerCompositor::requiresCompositingLayer): Use references.
+ (WebCore::RenderLayerCompositor::reasonsForCompositing): Use references.
+ * rendering/RenderLayerCompositor.h:
+
+2015-03-08 Simon Fraser <simon.fraser@apple.com>
+
</ins><span class="cx"> In RenderLayerCompositor, track layer bounds and the haveComputedBounds flag together in a struct
</span><span class="cx"> https://bugs.webkit.org/show_bug.cgi?id=142449
</span><span class="cx">
</span></span></pre></div>
<a id="trunkSourceWebCorerenderingRenderLayerCompositorcpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp (181246 => 181247)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp 2015-03-08 21:32:50 UTC (rev 181246)
+++ trunk/Source/WebCore/rendering/RenderLayerCompositor.cpp 2015-03-08 23:39:16 UTC (rev 181247)
</span><span class="lines">@@ -943,12 +943,30 @@
</span><span class="cx"> return (clipPath.type() != ClipPathOperation::Shape || clipPath.type() == ClipPathOperation::Shape) && GraphicsLayer::supportsLayerType(GraphicsLayer::Type::Shape);
</span><span class="cx"> }
</span><span class="cx">
</span><del>-bool RenderLayerCompositor::updateBacking(RenderLayer& layer, CompositingChangeRepaint shouldRepaint)
</del><ins>+static RenderLayerModelObject& rendererForCompositingTests(const RenderLayer& layer)
</ins><span class="cx"> {
</span><ins>+ RenderLayerModelObject* renderer = &layer.renderer();
+
+ // The compositing state of a reflection should match that of its reflected layer.
+ if (layer.isReflection())
+ renderer = downcast<RenderLayerModelObject>(renderer->parent()); // The RenderReplica's parent is the object being reflected.
+
+ return *renderer;
+}
+
+bool RenderLayerCompositor::updateBacking(RenderLayer& layer, CompositingChangeRepaint shouldRepaint, BackingRequired backingRequired)
+{
</ins><span class="cx"> bool layerChanged = false;
</span><span class="cx"> RenderLayer::ViewportConstrainedNotCompositedReason viewportConstrainedNotCompositedReason = RenderLayer::NoNotCompositedReason;
</span><span class="cx">
</span><del>- if (needsToBeComposited(layer, &viewportConstrainedNotCompositedReason)) {
</del><ins>+ if (backingRequired == BackingRequired::Unknown)
+ backingRequired = needsToBeComposited(layer, &viewportConstrainedNotCompositedReason) ? BackingRequired::Yes : BackingRequired::No;
+ else {
+ // Need to fetch viewportConstrainedNotCompositedReason, but without doing all the work that needsToBeComposited does.
+ requiresCompositingForPosition(rendererForCompositingTests(layer), layer, &viewportConstrainedNotCompositedReason);
+ }
+
+ if (backingRequired == BackingRequired::Yes) {
</ins><span class="cx"> enableCompositingMode();
</span><span class="cx">
</span><span class="cx"> if (!layer.backing()) {
</span><span class="lines">@@ -1243,10 +1261,11 @@
</span><span class="cx"> layer.setHasCompositingDescendant(false);
</span><span class="cx"> layer.setIndirectCompositingReason(RenderLayer::IndirectCompositingReason::None);
</span><span class="cx">
</span><del>- // Check if the layer needs to be composited for non-indirect reasons (ex. 3D transform).
- // We use this value to avoid checking the overlap-map, if we know for sure the layer
</del><ins>+ // Check if the layer needs to be composited for direct reasons (e.g. 3D transform).
+ // We use this value to avoid checking the overlap map, if we know for sure the layer
</ins><span class="cx"> // is already going to be composited for other reasons.
</span><span class="cx"> bool willBeComposited = needsToBeComposited(layer);
</span><ins>+ bool mayHaveAnimatedTransform = willBeComposited && !layer.isRootLayer();
</ins><span class="cx">
</span><span class="cx"> RenderLayer::IndirectCompositingReason compositingReason = compositingState.subtreeIsCompositing ? RenderLayer::IndirectCompositingReason::Stacking : RenderLayer::IndirectCompositingReason::None;
</span><span class="cx">
</span><span class="lines">@@ -1396,7 +1415,7 @@
</span><span class="cx"> // Turn overlap testing off for later layers if it's already off, or if we have an animating transform.
</span><span class="cx"> // Note that if the layer clips its descendants, there's no reason to propagate the child animation to the parent layers. That's because
</span><span class="cx"> // we know for sure the animation is contained inside the clipping rectangle, which is already added to the overlap map.
</span><del>- if ((!childState.testingOverlap && !isCompositedClippingLayer) || isRunningAcceleratedTransformAnimation(layer.renderer()))
</del><ins>+ if ((!childState.testingOverlap && !isCompositedClippingLayer) || (mayHaveAnimatedTransform && isRunningAcceleratedTransformAnimation(layer.renderer())))
</ins><span class="cx"> compositingState.testingOverlap = false;
</span><span class="cx">
</span><span class="cx"> if (isCompositedClippingLayer) {
</span><span class="lines">@@ -1434,7 +1453,7 @@
</span><span class="cx"> repaintOnCompositingChange(layer);
</span><span class="cx">
</span><span class="cx"> // Update backing now, so that we can use isComposited() reliably during tree traversal in rebuildCompositingLayerTree().
</span><del>- if (updateBacking(layer, CompositingChangeRepaintNow))
</del><ins>+ if (updateBacking(layer, CompositingChangeRepaintNow, willBeComposited ? BackingRequired::Yes : BackingRequired::No))
</ins><span class="cx"> layersChanged = true;
</span><span class="cx">
</span><span class="cx"> if (layer.reflectionLayer() && updateLayerCompositingState(*layer.reflectionLayer(), CompositingChangeRepaintNow))
</span><span class="lines">@@ -2136,27 +2155,23 @@
</span><span class="cx"> // static
</span><span class="cx"> bool RenderLayerCompositor::requiresCompositingLayer(const RenderLayer& layer, RenderLayer::ViewportConstrainedNotCompositedReason* viewportConstrainedNotCompositedReason) const
</span><span class="cx"> {
</span><del>- auto* renderer = &layer.renderer();
</del><ins>+ auto& renderer = rendererForCompositingTests(layer);
</ins><span class="cx">
</span><del>- // The compositing state of a reflection should match that of its reflected layer.
- if (layer.isReflection())
- renderer = downcast<RenderLayerModelObject>(renderer->parent()); // The RenderReplica's parent is the object being reflected.
-
</del><span class="cx"> // The root layer always has a compositing layer, but it may not have backing.
</span><del>- return requiresCompositingForTransform(*renderer)
- || requiresCompositingForVideo(*renderer)
- || requiresCompositingForCanvas(*renderer)
- || requiresCompositingForPlugin(*renderer)
- || requiresCompositingForFrame(*renderer)
- || requiresCompositingForBackfaceVisibility(*renderer)
- || clipsCompositingDescendants(*renderer->layer())
- || requiresCompositingForAnimation(*renderer)
- || requiresCompositingForFilters(*renderer)
- || requiresCompositingForPosition(*renderer, *renderer->layer(), viewportConstrainedNotCompositedReason)
</del><ins>+ return requiresCompositingForTransform(renderer)
+ || requiresCompositingForVideo(renderer)
+ || requiresCompositingForCanvas(renderer)
+ || requiresCompositingForPlugin(renderer)
+ || requiresCompositingForFrame(renderer)
+ || requiresCompositingForBackfaceVisibility(renderer)
+ || clipsCompositingDescendants(*renderer.layer())
+ || requiresCompositingForAnimation(renderer)
+ || requiresCompositingForFilters(renderer)
+ || requiresCompositingForPosition(renderer, *renderer.layer(), viewportConstrainedNotCompositedReason)
</ins><span class="cx"> #if PLATFORM(IOS)
</span><del>- || requiresCompositingForScrolling(*renderer->layer())
</del><ins>+ || requiresCompositingForScrolling(*renderer.layer())
</ins><span class="cx"> #endif
</span><del>- || requiresCompositingForOverflowScrolling(*renderer->layer());
</del><ins>+ || requiresCompositingForOverflowScrolling(*renderer.layer());
</ins><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> bool RenderLayerCompositor::canBeComposited(const RenderLayer& layer) const
</span><span class="lines">@@ -2229,46 +2244,44 @@
</span><span class="cx"> if (!layer.isComposited())
</span><span class="cx"> return reasons;
</span><span class="cx">
</span><del>- auto* renderer = &layer.renderer();
- if (layer.isReflection())
- renderer = downcast<RenderLayerModelObject>(renderer->parent());
</del><ins>+ auto& renderer = rendererForCompositingTests(layer);
</ins><span class="cx">
</span><del>- if (requiresCompositingForTransform(*renderer))
</del><ins>+ if (requiresCompositingForTransform(renderer))
</ins><span class="cx"> reasons |= CompositingReason3DTransform;
</span><span class="cx">
</span><del>- if (requiresCompositingForVideo(*renderer))
</del><ins>+ if (requiresCompositingForVideo(renderer))
</ins><span class="cx"> reasons |= CompositingReasonVideo;
</span><del>- else if (requiresCompositingForCanvas(*renderer))
</del><ins>+ else if (requiresCompositingForCanvas(renderer))
</ins><span class="cx"> reasons |= CompositingReasonCanvas;
</span><del>- else if (requiresCompositingForPlugin(*renderer))
</del><ins>+ else if (requiresCompositingForPlugin(renderer))
</ins><span class="cx"> reasons |= CompositingReasonPlugin;
</span><del>- else if (requiresCompositingForFrame(*renderer))
</del><ins>+ else if (requiresCompositingForFrame(renderer))
</ins><span class="cx"> reasons |= CompositingReasonIFrame;
</span><span class="cx">
</span><del>- if ((canRender3DTransforms() && renderer->style().backfaceVisibility() == BackfaceVisibilityHidden))
</del><ins>+ if ((canRender3DTransforms() && renderer.style().backfaceVisibility() == BackfaceVisibilityHidden))
</ins><span class="cx"> reasons |= CompositingReasonBackfaceVisibilityHidden;
</span><span class="cx">
</span><del>- if (clipsCompositingDescendants(*renderer->layer()))
</del><ins>+ if (clipsCompositingDescendants(*renderer.layer()))
</ins><span class="cx"> reasons |= CompositingReasonClipsCompositingDescendants;
</span><span class="cx">
</span><del>- if (requiresCompositingForAnimation(*renderer))
</del><ins>+ if (requiresCompositingForAnimation(renderer))
</ins><span class="cx"> reasons |= CompositingReasonAnimation;
</span><span class="cx">
</span><del>- if (requiresCompositingForFilters(*renderer))
</del><ins>+ if (requiresCompositingForFilters(renderer))
</ins><span class="cx"> reasons |= CompositingReasonFilters;
</span><span class="cx">
</span><del>- if (requiresCompositingForPosition(*renderer, *renderer->layer()))
- reasons |= renderer->style().position() == FixedPosition ? CompositingReasonPositionFixed : CompositingReasonPositionSticky;
</del><ins>+ if (requiresCompositingForPosition(renderer, *renderer.layer()))
+ reasons |= renderer.style().position() == FixedPosition ? CompositingReasonPositionFixed : CompositingReasonPositionSticky;
</ins><span class="cx">
</span><span class="cx"> #if PLATFORM(IOS)
</span><del>- if (requiresCompositingForScrolling(*renderer->layer()))
</del><ins>+ if (requiresCompositingForScrolling(*renderer.layer()))
</ins><span class="cx"> reasons |= CompositingReasonOverflowScrollingTouch;
</span><span class="cx"> #endif
</span><span class="cx">
</span><del>- if (requiresCompositingForOverflowScrolling(*renderer->layer()))
</del><ins>+ if (requiresCompositingForOverflowScrolling(*renderer.layer()))
</ins><span class="cx"> reasons |= CompositingReasonOverflowScrollingTouch;
</span><span class="cx">
</span><del>- switch (renderer->layer()->indirectCompositingReason()) {
</del><ins>+ switch (renderer.layer()->indirectCompositingReason()) {
</ins><span class="cx"> case RenderLayer::IndirectCompositingReason::None:
</span><span class="cx"> break;
</span><span class="cx"> case RenderLayer::IndirectCompositingReason::Stacking:
</span><span class="lines">@@ -2281,19 +2294,19 @@
</span><span class="cx"> reasons |= CompositingReasonNegativeZIndexChildren;
</span><span class="cx"> break;
</span><span class="cx"> case RenderLayer::IndirectCompositingReason::GraphicalEffect:
</span><del>- if (renderer->hasTransform())
</del><ins>+ if (renderer.hasTransform())
</ins><span class="cx"> reasons |= CompositingReasonTransformWithCompositedDescendants;
</span><span class="cx">
</span><del>- if (renderer->isTransparent())
</del><ins>+ if (renderer.isTransparent())
</ins><span class="cx"> reasons |= CompositingReasonOpacityWithCompositedDescendants;
</span><span class="cx">
</span><del>- if (renderer->hasMask())
</del><ins>+ if (renderer.hasMask())
</ins><span class="cx"> reasons |= CompositingReasonMaskWithCompositedDescendants;
</span><span class="cx">
</span><del>- if (renderer->hasReflection())
</del><ins>+ if (renderer.hasReflection())
</ins><span class="cx"> reasons |= CompositingReasonReflectionWithCompositedDescendants;
</span><span class="cx">
</span><del>- if (renderer->hasFilter() || renderer->hasBackdropFilter())
</del><ins>+ if (renderer.hasFilter() || renderer.hasBackdropFilter())
</ins><span class="cx"> reasons |= CompositingReasonFilterWithCompositedDescendants;
</span><span class="cx">
</span><span class="cx"> #if ENABLE(CSS_COMPOSITING)
</span><span class="lines">@@ -2312,7 +2325,7 @@
</span><span class="cx"> break;
</span><span class="cx"> }
</span><span class="cx">
</span><del>- if (inCompositingMode() && renderer->layer()->isRootLayer())
</del><ins>+ if (inCompositingMode() && renderer.layer()->isRootLayer())
</ins><span class="cx"> reasons |= CompositingReasonRoot;
</span><span class="cx">
</span><span class="cx"> return reasons;
</span></span></pre></div>
<a id="trunkSourceWebCorerenderingRenderLayerCompositorh"></a>
<div class="modfile"><h4>Modified: trunk/Source/WebCore/rendering/RenderLayerCompositor.h (181246 => 181247)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/WebCore/rendering/RenderLayerCompositor.h 2015-03-08 21:32:50 UTC (rev 181246)
+++ trunk/Source/WebCore/rendering/RenderLayerCompositor.h 2015-03-08 23:39:16 UTC (rev 181247)
</span><span class="lines">@@ -293,7 +293,7 @@
</span><span class="cx">
</span><span class="cx"> void setShouldReevaluateCompositingAfterLayout() { m_reevaluateCompositingAfterLayout = true; }
</span><span class="cx">
</span><del>- bool viewHasTransparentBackground(Color* backgroundColor = 0) const;
</del><ins>+ bool viewHasTransparentBackground(Color* backgroundColor = nullptr) const;
</ins><span class="cx">
</span><span class="cx"> bool hasNonMainLayersWithTiledBacking() const { return m_layersWithTiledBackingCount; }
</span><span class="cx">
</span><span class="lines">@@ -322,14 +322,15 @@
</span><span class="cx"> virtual void flushLayersSoon(GraphicsLayerUpdater*) override;
</span><span class="cx">
</span><span class="cx"> // Whether the given RL needs a compositing layer.
</span><del>- bool needsToBeComposited(const RenderLayer&, RenderLayer::ViewportConstrainedNotCompositedReason* = 0) const;
</del><ins>+ bool needsToBeComposited(const RenderLayer&, RenderLayer::ViewportConstrainedNotCompositedReason* = nullptr) const;
</ins><span class="cx"> // Whether the layer has an intrinsic need for compositing layer.
</span><del>- bool requiresCompositingLayer(const RenderLayer&, RenderLayer::ViewportConstrainedNotCompositedReason* = 0) const;
</del><ins>+ bool requiresCompositingLayer(const RenderLayer&, RenderLayer::ViewportConstrainedNotCompositedReason* = nullptr) const;
</ins><span class="cx"> // Whether the layer could ever be composited.
</span><span class="cx"> bool canBeComposited(const RenderLayer&) const;
</span><span class="cx">
</span><span class="cx"> // Make or destroy the backing for this layer; returns true if backing changed.
</span><del>- bool updateBacking(RenderLayer&, CompositingChangeRepaint shouldRepaint);
</del><ins>+ enum class BackingRequired { No, Yes, Unknown };
+ bool updateBacking(RenderLayer&, CompositingChangeRepaint shouldRepaint, BackingRequired = BackingRequired::Unknown);
</ins><span class="cx">
</span><span class="cx"> void clearBackingForLayerIncludingDescendants(RenderLayer&);
</span><span class="cx"> void setIsInWindowForLayerIncludingDescendants(RenderLayer&, bool isInWindow);
</span><span class="lines">@@ -410,7 +411,7 @@
</span><span class="cx"> bool requiresCompositingForFrame(RenderLayerModelObject&) const;
</span><span class="cx"> bool requiresCompositingForFilters(RenderLayerModelObject&) const;
</span><span class="cx"> bool requiresCompositingForScrollableFrame() const;
</span><del>- bool requiresCompositingForPosition(RenderLayerModelObject&, const RenderLayer&, RenderLayer::ViewportConstrainedNotCompositedReason* = 0) const;
</del><ins>+ bool requiresCompositingForPosition(RenderLayerModelObject&, const RenderLayer&, RenderLayer::ViewportConstrainedNotCompositedReason* = nullptr) const;
</ins><span class="cx"> bool requiresCompositingForOverflowScrolling(const RenderLayer&) const;
</span><span class="cx"> bool requiresCompositingForIndirectReason(RenderLayerModelObject&, bool hasCompositedDescendants, bool has3DTransformedDescendants, RenderLayer::IndirectCompositingReason&) const;
</span><span class="cx">
</span></span></pre>
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