Bug 1404297 - Change the way we iterate over our links to update. r=smaug

MozReview-Commit-ID: BTADrB9itjh

--HG--
extra : rebase_source : 858f50bdbe2c35541b6a1975b0814e560db254c8

dom/base/nsDocument.cpp

@@ -1445,8 +1445,8 @@ nsIDocument::nsIDocument()
     mHasHadScriptHandlingObject(false),
     mIsBeingUsedAsImage(false),
     mIsSyntheticDocument(false),
-    mHasLinksToUpdate(false),
     mHasLinksToUpdateRunnable(false),
+    mFlushingPendingLinkUpdates(false),
     mMayHaveDOMMutationObservers(false),
     mMayHaveAnimationObservers(false),
     mHasMixedActiveContentLoaded(false),
@@ -1491,7 +1491,6 @@ nsIDocument::nsIDocument()
     mType(eUnknown),
     mDefaultElementType(0),
     mAllowXULXBL(eTriUnset),
-    mIsLinkUpdateRegistrationsForbidden(false),
     mBidiOptions(IBMBIDI_DEFAULT_BIDI_OPTIONS),
     mSandboxFlags(0),
     mPartID(0),
@@ -9612,15 +9611,13 @@ nsIDocument::EnumerateActivityObservers(ActivityObserverEnumerator aEnumerator,
 void
 nsIDocument::RegisterPendingLinkUpdate(Link* aLink)
 {
-  MOZ_RELEASE_ASSERT(!mIsLinkUpdateRegistrationsForbidden);
-
   if (aLink->HasPendingLinkUpdate()) {
     return;
   }
 
   aLink->SetHasPendingLinkUpdate();
 
-  if (!mHasLinksToUpdateRunnable) {
+  if (!mHasLinksToUpdateRunnable && !mFlushingPendingLinkUpdates) {
     nsCOMPtr<nsIRunnable> event =
       NewRunnableMethod("nsIDocument::FlushPendingLinkUpdatesFromRunnable",
                         this,
@@ -9637,7 +9634,6 @@ nsIDocument::RegisterPendingLinkUpdate(Link* aLink)
   }
 
   mLinksToUpdate.InfallibleAppend(aLink);
-  mHasLinksToUpdate = true;
 }
 
 void
@@ -9651,24 +9647,26 @@ nsIDocument::FlushPendingLinkUpdatesFromRunnable()
 void
 nsIDocument::FlushPendingLinkUpdates()
 {
-  MOZ_RELEASE_ASSERT(!mIsLinkUpdateRegistrationsForbidden);
-  if (!mHasLinksToUpdate)
+  if (mFlushingPendingLinkUpdates) {
     return;
+  }
 
-  AutoRestore<bool> saved(mIsLinkUpdateRegistrationsForbidden);
-  mIsLinkUpdateRegistrationsForbidden = true;
-  for (auto iter = mLinksToUpdate.Iter(); !iter.Done(); iter.Next()) {
-    Link* link = iter.Get();
-    Element* element = link->GetElement();
-    if (element->OwnerDoc() == this) {
-      link->ClearHasPendingLinkUpdate();
-      if (element->IsInComposedDoc()) {
-        element->UpdateLinkState(link->LinkState());
+  auto restore = MakeScopeExit([&] { mFlushingPendingLinkUpdates = false; });
+  mFlushingPendingLinkUpdates = true;
+
+  while (!mLinksToUpdate.IsEmpty()) {
+    LinksToUpdateList links(Move(mLinksToUpdate));
+    for (auto iter = links.Iter(); !iter.Done(); iter.Next()) {
+      Link* link = iter.Get();
+      Element* element = link->GetElement();
+      if (element->OwnerDoc() == this) {
+        link->ClearHasPendingLinkUpdate();
+        if (element->IsInComposedDoc()) {
+          element->UpdateLinkState(link->LinkState());
+        }
       }
     }
   }
-  mLinksToUpdate.Clear();
-  mHasLinksToUpdate = false;
 }
 
 already_AddRefed<nsIDocument>

dom/base/nsIDocument.h

@@ -3344,10 +3344,13 @@ protected:
   // The array of all links that need their status resolved.  Links must add themselves
   // to this set by calling RegisterPendingLinkUpdate when added to a document.
   static const size_t kSegmentSize = 128;
-  mozilla::SegmentedVector<nsCOMPtr<mozilla::dom::Link>,
-                           kSegmentSize,
-                           InfallibleAllocPolicy>
-    mLinksToUpdate;
+
+  typedef mozilla::SegmentedVector<nsCOMPtr<mozilla::dom::Link>,
+                                   kSegmentSize,
+                                   InfallibleAllocPolicy>
+    LinksToUpdateList;
+
+  LinksToUpdateList mLinksToUpdate;
 
   // SMIL Animation Controller, lazily-initialized in GetAnimationController
   RefPtr<nsSMILAnimationController> mAnimationController;
@@ -3441,12 +3444,12 @@ protected:
   // file, etc.
   bool mIsSyntheticDocument : 1;
 
-  // True if this document has links whose state needs updating
-  bool mHasLinksToUpdate : 1;
-
   // True is there is a pending runnable which will call FlushPendingLinkUpdates().
   bool mHasLinksToUpdateRunnable : 1;
 
+  // True if we're flushing pending link updates.
+  bool mFlushingPendingLinkUpdates : 1;
+
   // True if a DOMMutationObserver is perhaps attached to a node in the document.
   bool mMayHaveDOMMutationObservers : 1;
 
@@ -3595,12 +3598,6 @@ protected:
 
   Tri mAllowXULXBL;
 
-  /**
-   * This is true while FlushPendingLinkUpdates executes.  Calls to
-   * [Un]RegisterPendingLinkUpdate will assert when this is true.
-   */
-  bool mIsLinkUpdateRegistrationsForbidden;
-
   // The document's script global object, the object from which the
   // document can get its script context and scope. This is the
   // *inner* window object.