Bug 1488599 - Part 1: Add RetainedDisplayListData that will store frame invalidation information r=mattwoodrow

Differential Revision: https://phabricator.services.mozilla.com/D5245

--HG--
extra : moz-landing-system : lando

layout/base/nsLayoutUtils.cpp

@@ -479,6 +479,14 @@ nsLayoutUtils::AreRetainedDisplayListsEnabled()
   return false;
 }
 
+bool
+nsLayoutUtils::DisplayRootHasRetainedDisplayListBuilder(nsIFrame* aFrame)
+{
+  const nsIFrame* displayRoot = nsLayoutUtils::GetDisplayRootFrame(aFrame);
+  MOZ_ASSERT(displayRoot);
+  return displayRoot->HasProperty(RetainedDisplayListBuilder::Cached());
+}
+
 bool
 nsLayoutUtils::GPUImageScalingEnabled()
 {
@@ -1188,15 +1196,8 @@ nsLayoutUtils::InvalidateForDisplayPortChange(nsIContent* aContent,
     // rect properties on so we can find the frame later to remove the properties.
     frame->SchedulePaint();
 
-    if (!nsLayoutUtils::AreRetainedDisplayListsEnabled()) {
-      return;
-    }
-
-    nsIFrame* displayRoot = nsLayoutUtils::GetDisplayRootFrame(frame);
-    RetainedDisplayListBuilder* retainedBuilder =
-      displayRoot->GetProperty(RetainedDisplayListBuilder::Cached());
-
-    if (!retainedBuilder) {
+    if (!nsLayoutUtils::AreRetainedDisplayListsEnabled() ||
+        !nsLayoutUtils::DisplayRootHasRetainedDisplayListBuilder(frame)) {
       return;
     }
 
@@ -1208,18 +1209,12 @@ nsLayoutUtils::InvalidateForDisplayPortChange(nsIContent* aContent,
       frame->SetProperty(nsDisplayListBuilder::DisplayListBuildingDisplayPortRect(), rect);
       frame->SetHasOverrideDirtyRegion(true);
 
-      nsIFrame* rootFrame = frame->PresContext()->PresShell()->GetRootFrame();
+      nsIFrame* rootFrame = frame->PresShell()->GetRootFrame();
       MOZ_ASSERT(rootFrame);
 
-      nsTArray<nsIFrame*>* frames =
-        rootFrame->GetProperty(nsIFrame::OverriddenDirtyRectFrameList());
-
-      if (!frames) {
-        frames = new nsTArray<nsIFrame*>();
-        rootFrame->SetProperty(nsIFrame::OverriddenDirtyRectFrameList(), frames);
-      }
-
-      frames->AppendElement(frame);
+      RetainedDisplayListData* data =
+        GetOrSetRetainedDisplayListData(rootFrame);
+      data->Flags(frame) |= RetainedDisplayListData::FrameFlags::HasProps;
     }
 
     if (aHadDisplayPort) {

layout/base/nsLayoutUtils.h

@@ -2375,6 +2375,8 @@ public:
    */
   static bool AreRetainedDisplayListsEnabled();
 
+  static bool DisplayRootHasRetainedDisplayListBuilder(nsIFrame* aFrame);
+
   /**
    * Find a suitable scale for a element (aFrame's content) over the course of any
    * animations and transitions of the CSS transform property on the

layout/generic/nsFrame.cpp

@@ -829,12 +829,14 @@ nsFrame::DestroyFrom(nsIFrame* aDestructRoot, PostDestroyData& aPostDestroyData)
     nsIFrame* rootFrame = shell->GetRootFrame();
     MOZ_ASSERT(rootFrame);
     if (this != rootFrame) {
-      nsTArray<nsIFrame*>* modifiedFrames =
-        rootFrame->GetProperty(nsIFrame::ModifiedFrameList());
-      if (modifiedFrames) {
-        MOZ_ASSERT(!modifiedFrames->Contains(this),
-                   "A dtor added this frame to ModifiedFrameList");
-      }
+      const RetainedDisplayListData* data =
+        GetRetainedDisplayListData(rootFrame);
+
+      const bool inModifiedList = data &&
+        (data->GetFlags(this) & RetainedDisplayListData::FrameFlags::Modified);
+
+      MOZ_ASSERT(!inModifiedList,
+                 "A dtor added this frame to modified frames list!");
     }
   }
 #endif
@@ -965,36 +967,30 @@ nsIFrame::RemoveDisplayItemDataForDeletion()
     delete items;
   }
 
-  if (IsFrameModified()) {
-    nsIFrame* rootFrame = PresShell()->GetRootFrame();
-    MOZ_ASSERT(rootFrame);
-
-    nsTArray<nsIFrame*>* modifiedFrames =
-      rootFrame->GetProperty(nsIFrame::ModifiedFrameList());
-    MOZ_ASSERT(modifiedFrames);
-
-    for (auto& frame : *modifiedFrames) {
-      if (frame == this) {
-        frame = nullptr;
-        break;
-      }
-    }
+  if (!nsLayoutUtils::AreRetainedDisplayListsEnabled()) {
+    // Retained display lists are disabled, no need to update
+    // RetainedDisplayListData.
+    return;
   }
 
-  if (HasOverrideDirtyRegion()) {
-    nsIFrame* rootFrame = PresShell()->GetRootFrame();
-    MOZ_ASSERT(rootFrame);
+  const bool updateData =
+    IsFrameModified() || HasOverrideDirtyRegion() || MayHaveWillChangeBudget();
 
-    nsTArray<nsIFrame*>* frames =
-      rootFrame->GetProperty(nsIFrame::OverriddenDirtyRectFrameList());
-    MOZ_ASSERT(frames);
+  if (!updateData) {
+    // No RetainedDisplayListData to update.
+    return;
+  }
 
-    for (auto& frame : *frames) {
-      if (frame == this) {
-        frame = nullptr;
-        break;
-      }
-    }
+  nsIFrame* rootFrame = PresShell()->GetRootFrame();
+  MOZ_ASSERT(rootFrame);
+
+  RetainedDisplayListData* data = GetOrSetRetainedDisplayListData(rootFrame);
+
+  if (IsFrameModified() || HasOverrideDirtyRegion()) {
+    // Remove deleted frames from RetainedDisplayListData.
+    DebugOnly<bool> removed = data->Remove(this);
+    MOZ_ASSERT(removed,
+               "Frame had flags set, but it was not found in DisplayListData!");
   }
 }
 
@@ -1017,13 +1013,7 @@ nsIFrame::MarkNeedsDisplayItemRebuild()
     return;
   }
 
-  nsIFrame* displayRoot = nsLayoutUtils::GetDisplayRootFrame(this);
-  MOZ_ASSERT(displayRoot);
-
-  RetainedDisplayListBuilder* retainedBuilder =
-    displayRoot->GetProperty(RetainedDisplayListBuilder::Cached());
-
-  if (!retainedBuilder) {
+  if (!nsLayoutUtils::DisplayRootHasRetainedDisplayListBuilder(this)) {
     return;
   }
 
@@ -1034,36 +1024,13 @@ nsIFrame::MarkNeedsDisplayItemRebuild()
     return;
   }
 
-  nsTArray<nsIFrame*>* modifiedFrames =
-    rootFrame->GetProperty(nsIFrame::ModifiedFrameList());
-
-  if (!modifiedFrames) {
-    modifiedFrames = new nsTArray<nsIFrame*>();
-    rootFrame->SetProperty(nsIFrame::ModifiedFrameList(), modifiedFrames);
-  }
-
-  if (this == rootFrame) {
-    // If this is the root frame, then marking us as needing a display
-    // item rebuild implies the same for all our descendents. Clear them
-    // all out to reduce the number of modified frames we keep around.
-    for (nsIFrame* f : *modifiedFrames) {
-      if (f) {
-        f->SetFrameIsModified(false);
-      }
-    }
-    modifiedFrames->Clear();
-  } else if (modifiedFrames->Length() > gfxPrefs::LayoutRebuildFrameLimit()) {
-    // If the list starts getting too big, then just mark the root frame
-    // as needing a rebuild.
-    rootFrame->MarkNeedsDisplayItemRebuild();
-    return;
-  }
-
-  modifiedFrames->AppendElement(this);
-
-  MOZ_ASSERT(PresContext()->LayoutPhaseCount(eLayoutPhase_DisplayListBuilding) == 0);
+  RetainedDisplayListData* data = GetOrSetRetainedDisplayListData(rootFrame);
+  data->Flags(this) |= RetainedDisplayListData::FrameFlags::Modified;
   SetFrameIsModified(true);
 
+  MOZ_ASSERT(
+    PresContext()->LayoutPhaseCount(eLayoutPhase_DisplayListBuilding) == 0);
+
   // Hopefully this is cheap, but we could use a frame state bit to note
   // the presence of dependencies to speed it up.
   DisplayItemArray* items = GetProperty(DisplayItems());

layout/generic/nsIFrame.h

@@ -1251,8 +1251,6 @@ public:
   NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(IBaselinePadProperty, nscoord)
   NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(BBaselinePadProperty, nscoord)
 
-  NS_DECLARE_FRAME_PROPERTY_DELETABLE(ModifiedFrameList, nsTArray<nsIFrame*>)
-  NS_DECLARE_FRAME_PROPERTY_DELETABLE(OverriddenDirtyRectFrameList, nsTArray<nsIFrame*>)
   NS_DECLARE_FRAME_PROPERTY_DELETABLE(DisplayItems, DisplayItemArray)
 
   NS_DECLARE_FRAME_PROPERTY_SMALL_VALUE(BidiDataProperty, mozilla::FrameBidiData)

layout/painting/RetainedDisplayListBuilder.cpp

@@ -41,6 +41,29 @@
 
 using namespace mozilla;
 
+RetainedDisplayListData*
+GetRetainedDisplayListData(nsIFrame* aRootFrame)
+{
+  RetainedDisplayListData* data =
+    aRootFrame->GetProperty(RetainedDisplayListData::DisplayListData());
+
+  return data;
+}
+
+RetainedDisplayListData*
+GetOrSetRetainedDisplayListData(nsIFrame* aRootFrame)
+{
+  RetainedDisplayListData* data = GetRetainedDisplayListData(aRootFrame);
+
+  if (!data) {
+    data = new RetainedDisplayListData();
+    aRootFrame->SetProperty(RetainedDisplayListData::DisplayListData(), data);
+  }
+
+  MOZ_ASSERT(data);
+  return data;
+}
+
 static void
 MarkFramesWithItemsAndImagesModified(nsDisplayList* aList)
 {
@@ -643,30 +666,26 @@ TakeAndAddModifiedAndFramesWithPropsFromRootFrame(
 {
   MOZ_ASSERT(aRootFrame);
 
-  nsTArray<nsIFrame*>* frames =
-    aRootFrame->GetProperty(nsIFrame::ModifiedFrameList());
+  RetainedDisplayListData* data = GetRetainedDisplayListData(aRootFrame);
 
-  if (frames) {
-    for (nsIFrame* f : *frames) {
-      if (f) {
-        aModifiedFrames->AppendElement(f);
-      }
-    }
-
-    frames->Clear();
+  if (!data) {
+    return;
   }
 
-  frames = aRootFrame->GetProperty(nsIFrame::OverriddenDirtyRectFrameList());
+  for (auto it = data->Iterator(); !it.Done(); it.Next()) {
+    nsIFrame* frame = it.Key();
+    const RetainedDisplayListData::FrameFlags& flags = it.Data();
 
-  if (frames) {
-    for (nsIFrame* f : *frames) {
-      if (f) {
-        aFramesWithProps->AppendElement(f);
-      }
+    if (flags & RetainedDisplayListData::FrameFlags::Modified) {
+      aModifiedFrames->AppendElement(frame);
     }
 
-    frames->Clear();
+    if (flags & RetainedDisplayListData::FrameFlags::HasProps) {
+      aFramesWithProps->AppendElement(frame);
+    }
   }
+
+  data->Clear();
 }
 
 struct CbData
@@ -1230,6 +1249,11 @@ ClearFrameProps(nsTArray<nsIFrame*>& aFrames)
 class AutoClearFramePropsArray
 {
 public:
+  explicit AutoClearFramePropsArray(size_t aCapacity)
+    : mFrames(aCapacity)
+  {
+  }
+
   AutoClearFramePropsArray() = default;
 
   ~AutoClearFramePropsArray() { ClearFrameProps(mFrames); }
@@ -1268,7 +1292,7 @@ RetainedDisplayListBuilder::AttemptPartialUpdate(
   // We set the override dirty regions during ComputeRebuildRegion or in
   // nsLayoutUtils::InvalidateForDisplayPortChange. The display port change also
   // marks the frame modified, so those regions are cleared here as well.
-  AutoClearFramePropsArray modifiedFrames;
+  AutoClearFramePropsArray modifiedFrames(64);
   AutoClearFramePropsArray framesWithProps;
   GetModifiedAndFramesWithProps(
     &mBuilder, &modifiedFrames.Frames(), &framesWithProps.Frames());

layout/painting/RetainedDisplayListBuilder.h

@@ -9,11 +9,78 @@
 
 #include "nsDisplayList.h"
 #include "mozilla/Maybe.h"
+#include "mozilla/TypedEnumBits.h"
 
 namespace mozilla {
 class DisplayListChecker;
 } // namespace mozilla
 
+
+/**
+ * RetainedDisplayListData contains frame invalidation information. It is stored
+ * in root frames, and used by RetainedDisplayListBuilder.
+ * Currently this is implemented as a map of frame pointers to flags.
+ */
+struct RetainedDisplayListData
+{
+  NS_DECLARE_FRAME_PROPERTY_DELETABLE(DisplayListData, RetainedDisplayListData)
+
+  enum class FrameFlags : uint8_t
+  {
+    None = 0,
+    Modified = 1 << 0,
+    HasProps = 1 << 1,
+    HadWillChange = 1 << 2
+  };
+
+  /**
+   * Removes all the frames from this RetainedDisplayListData.
+   */
+  void Clear() { mFrames.Clear(); }
+
+  /**
+   * Returns a mutable reference to flags set for the given |aFrame|. If the
+   * frame does not exist in this RetainedDisplayListData, it is added with
+   * default constructible flags FrameFlags::None.
+   */
+  FrameFlags& Flags(nsIFrame* aFrame) { return mFrames.GetOrInsert(aFrame); }
+
+  /**
+   * Returns flags set for the given |aFrame|, or FrameFlags::None if the frame
+   * is not in this RetainedDisplayListData.
+   */
+  FrameFlags GetFlags(nsIFrame* aFrame) const { return mFrames.Get(aFrame); }
+
+  /**
+   * Returns an iterator to the underlying frame storage.
+   */
+  auto Iterator() { return mFrames.Iter(); }
+
+  /**
+   * Removes the given |aFrame| from this RetainedDisplayListData.
+   */
+  bool Remove(nsIFrame* aFrame) { return mFrames.Remove(aFrame); }
+
+private:
+  nsDataHashtable<nsPtrHashKey<nsIFrame>, FrameFlags> mFrames;
+};
+
+MOZ_MAKE_ENUM_CLASS_BITWISE_OPERATORS(RetainedDisplayListData::FrameFlags)
+
+/**
+ * Returns RetainedDisplayListData property for the given |aRootFrame|, or
+ * nullptr if the property is not set.
+ */
+RetainedDisplayListData*
+GetRetainedDisplayListData(nsIFrame* aRootFrame);
+
+/**
+ * Returns RetainedDisplayListData property for the given |aRootFrame|. Creates
+ * and sets a new RetainedDisplayListData property if it is not already set.
+ */
+RetainedDisplayListData*
+GetOrSetRetainedDisplayListData(nsIFrame* aRootFrame);
+
 struct RetainedDisplayListBuilder
 {
   RetainedDisplayListBuilder(nsIFrame* aReferenceFrame,

layout/painting/nsDisplayList.h

@@ -3359,7 +3359,7 @@ public:
   /**
    * Remove all items from the list and call their destructors.
    */
-  void DeleteAll(nsDisplayListBuilder* aBuilder);
+  virtual void DeleteAll(nsDisplayListBuilder* aBuilder);
 
   /**
    * @return the item at the top of the list, or null if the list is empty
@@ -3754,7 +3754,7 @@ public:
     return *this;
   }
 
-  void DeleteAll(nsDisplayListBuilder* aBuilder)
+  void DeleteAll(nsDisplayListBuilder* aBuilder) override
   {
     for (OldItemInfo& i : mOldItems) {
       if (i.mItem) {