RestyleTracker.cpp
/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
* A class which manages pending restyles. This handles keeping track
* of what nodes restyles need to happen on and so forth.
*/
#include "RestyleTracker.h"
#include "GeckoProfiler.h"
#include "nsDocShell.h"
#include "nsFrameManager.h"
#include "nsIDocument.h"
#include "nsStyleChangeList.h"
#include "mozilla/RestyleManager.h"
#include "RestyleTrackerInlines.h"
#include "nsTransitionManager.h"
#include "mozilla/RestyleTimelineMarker.h"
namespace mozilla {
#ifdef RESTYLE_LOGGING
static nsCString
GetDocumentURI(nsIDocument* aDocument)
{
nsCString result;
nsString url;
aDocument->GetDocumentURI(url);
result.Append(NS_ConvertUTF16toUTF8(url).get());
return result;
}
static nsCString
FrameTagToString(dom::Element* aElement)
{
nsCString result;
nsIFrame* frame = aElement->GetPrimaryFrame();
if (frame) {
nsFrame::ListTag(result, frame);
} else {
nsAutoString buf;
aElement->NodeInfo()->NameAtom()->ToString(buf);
result.AppendPrintf("(%s@%p)", NS_ConvertUTF16toUTF8(buf).get(), aElement);
}
return result;
}
#endif
inline nsIDocument*
RestyleTracker::Document() const {
return mRestyleManager->PresContext()->Document();
}
#define RESTYLE_ARRAY_STACKSIZE 128
struct RestyleEnumerateData : RestyleTracker::Hints {
RefPtr<dom::Element> mElement;
#if defined(MOZ_ENABLE_PROFILER_SPS)
UniquePtr<ProfilerBacktrace> mBacktrace;
#endif
};
inline void
RestyleTracker::ProcessOneRestyle(Element* aElement,
nsRestyleHint aRestyleHint,
nsChangeHint aChangeHint,
const RestyleHintData& aRestyleHintData)
{
NS_PRECONDITION((aRestyleHint & eRestyle_LaterSiblings) == 0,
"Someone should have handled this before calling us");
NS_PRECONDITION(Document(), "Must have a document");
NS_PRECONDITION(aElement->GetComposedDoc() == Document(),
"Element has unexpected document");
LOG_RESTYLE("aRestyleHint = %s, aChangeHint = %s",
RestyleManager::RestyleHintToString(aRestyleHint).get(),
RestyleManager::ChangeHintToString(aChangeHint).get());
nsIFrame* primaryFrame = aElement->GetPrimaryFrame();
if (aRestyleHint & ~eRestyle_LaterSiblings) {
#ifdef RESTYLE_LOGGING
if (ShouldLogRestyle() && primaryFrame &&
RestyleManager::StructsToLog() != 0) {
LOG_RESTYLE("style context tree before restyle:");
LOG_RESTYLE_INDENT();
primaryFrame->StyleContext()->LogStyleContextTree(
LoggingDepth(), RestyleManager::StructsToLog());
}
#endif
mRestyleManager->RestyleElement(aElement, primaryFrame, aChangeHint,
*this, aRestyleHint, aRestyleHintData);
} else if (aChangeHint &&
(primaryFrame ||
(aChangeHint & nsChangeHint_ReconstructFrame))) {
// Don't need to recompute style; just apply the hint
nsStyleChangeList changeList;
changeList.AppendChange(primaryFrame, aElement, aChangeHint);
mRestyleManager->ProcessRestyledFrames(changeList);
}
}
void
RestyleTracker::DoProcessRestyles()
{
nsAutoCString docURL;
if (profiler_is_active()) {
nsIURI *uri = Document()->GetDocumentURI();
if (uri) {
uri->GetSpec(docURL);
} else {
docURL = "N/A";
}
}
PROFILER_LABEL_PRINTF("RestyleTracker", "ProcessRestyles",
js::ProfileEntry::Category::CSS, "(%s)", docURL.get());
nsDocShell* docShell = static_cast<nsDocShell*>(mRestyleManager->PresContext()->GetDocShell());
RefPtr<TimelineConsumers> timelines = TimelineConsumers::Get();
bool isTimelineRecording = timelines && timelines->HasConsumer(docShell);
// Create a AnimationsWithDestroyedFrame during restyling process to
// stop animations and transitions on elements that have no frame at the end
// of the restyling process.
RestyleManager::AnimationsWithDestroyedFrame
animationsWithDestroyedFrame(mRestyleManager);
// Create a ReframingStyleContexts struct on the stack and put it in our
// mReframingStyleContexts for almost all of the remaining scope of
// this function.
//
// It needs to be *in* scope during BeginProcessingRestyles, which
// might (if mDoRebuildAllStyleData is true) do substantial amounts of
// restyle processing.
//
// However, it needs to be *out* of scope during
// EndProcessingRestyles, since we should release the style contexts
// it holds prior to any EndReconstruct call that
// EndProcessingRestyles makes. This is because in EndReconstruct we
// try to destroy the old rule tree using the GC mechanism, which
// means it only gets destroyed if it's unreferenced (and if it's
// referenced, we assert). So we want the ReframingStyleContexts
// (which holds old style contexts) to be destroyed before the
// EndReconstruct so those style contexts go away before
// EndReconstruct.
{
RestyleManager::ReframingStyleContexts
reframingStyleContexts(mRestyleManager);
mRestyleManager->BeginProcessingRestyles(*this);
LOG_RESTYLE("Processing %d pending %srestyles with %d restyle roots for %s",
mPendingRestyles.Count(),
mRestyleManager->PresContext()->TransitionManager()->
InAnimationOnlyStyleUpdate()
? (const char*) "animation " : (const char*) "",
static_cast<int>(mRestyleRoots.Length()),
GetDocumentURI(Document()).get());
LOG_RESTYLE_INDENT();
// loop so that we process any restyle events generated by processing
while (mPendingRestyles.Count()) {
if (mHaveLaterSiblingRestyles) {
// Convert them to individual restyles on all the later siblings
AutoTArray<RefPtr<Element>, RESTYLE_ARRAY_STACKSIZE> laterSiblingArr;
for (auto iter = mPendingRestyles.Iter(); !iter.Done(); iter.Next()) {
auto element = static_cast<dom::Element*>(iter.Key());
// Only collect the entries that actually need restyling by us (and
// haven't, for example, already been restyled).
// It's important to not mess with the flags on entries not in our
// document.
if (element->GetComposedDoc() == Document() &&
element->HasFlag(RestyleBit()) &&
(iter.Data()->mRestyleHint & eRestyle_LaterSiblings)) {
laterSiblingArr.AppendElement(element);
}
}
for (uint32_t i = 0; i < laterSiblingArr.Length(); ++i) {
Element* element = laterSiblingArr[i];
for (nsIContent* sibling = element->GetNextSibling();
sibling;
sibling = sibling->GetNextSibling()) {
if (sibling->IsElement()) {
LOG_RESTYLE("adding pending restyle for %s due to "
"eRestyle_LaterSiblings hint on %s",
FrameTagToString(sibling->AsElement()).get(),
FrameTagToString(element->AsElement()).get());
if (AddPendingRestyle(sibling->AsElement(), eRestyle_Subtree,
NS_STYLE_HINT_NONE)) {
// Nothing else to do here; we'll handle the following
// siblings when we get to |sibling| in laterSiblingArr.
break;
}
}
}
}
// Now remove all those eRestyle_LaterSiblings bits
for (uint32_t i = 0; i < laterSiblingArr.Length(); ++i) {
Element* element = laterSiblingArr[i];
NS_ASSERTION(element->HasFlag(RestyleBit()), "How did that happen?");
RestyleData* data;
#ifdef DEBUG
bool found =
#endif
mPendingRestyles.Get(element, &data);
NS_ASSERTION(found, "Where did our entry go?");
data->mRestyleHint =
nsRestyleHint(data->mRestyleHint & ~eRestyle_LaterSiblings);
}
LOG_RESTYLE("%d pending restyles after expanding out "
"eRestyle_LaterSiblings", mPendingRestyles.Count());
mHaveLaterSiblingRestyles = false;
}
uint32_t rootCount;
while ((rootCount = mRestyleRoots.Length())) {
// Make sure to pop the element off our restyle root array, so
// that we can freely append to the array as we process this
// element.
RefPtr<Element> element;
element.swap(mRestyleRoots[rootCount - 1]);
mRestyleRoots.RemoveElementAt(rootCount - 1);
LOG_RESTYLE("processing style root %s at index %d",
FrameTagToString(element).get(), rootCount - 1);
LOG_RESTYLE_INDENT();
// Do the document check before calling GetRestyleData, since we
// don't want to do the sibling-processing GetRestyleData does if
// the node is no longer relevant.
if (element->GetComposedDoc() != Document()) {
// Content node has been removed from our document; nothing else
// to do here
LOG_RESTYLE("skipping, no longer in the document");
continue;
}
nsAutoPtr<RestyleData> data;
if (!GetRestyleData(element, data)) {
LOG_RESTYLE("skipping, already restyled");
continue;
}
if (isTimelineRecording) {
timelines->AddMarkerForDocShell(docShell, Move(
MakeUnique<RestyleTimelineMarker>(
data->mRestyleHint, MarkerTracingType::START)));
}
#if defined(MOZ_ENABLE_PROFILER_SPS)
Maybe<GeckoProfilerTracingRAII> profilerRAII;
if (profiler_feature_active("restyle")) {
profilerRAII.emplace("Paint", "Styles", Move(data->mBacktrace));
}
#endif
ProcessOneRestyle(element, data->mRestyleHint, data->mChangeHint,
data->mRestyleHintData);
AddRestyleRootsIfAwaitingRestyle(data->mDescendants);
if (isTimelineRecording) {
timelines->AddMarkerForDocShell(docShell, Move(
MakeUnique<RestyleTimelineMarker>(
data->mRestyleHint, MarkerTracingType::END)));
}
}
if (mHaveLaterSiblingRestyles) {
// Keep processing restyles for now
continue;
}
// Now we only have entries with change hints left. To be safe in
// case of reentry from the handing of the change hint, use a
// scratch array instead of calling out to ProcessOneRestyle while
// enumerating the hashtable. Use the stack if we can, otherwise
// fall back on heap-allocation.
AutoTArray<RestyleEnumerateData, RESTYLE_ARRAY_STACKSIZE> restyleArr;
RestyleEnumerateData* restylesToProcess =
restyleArr.AppendElements(mPendingRestyles.Count());
if (restylesToProcess) {
RestyleEnumerateData* restyle = restylesToProcess;
#ifdef RESTYLE_LOGGING
uint32_t count = 0;
#endif
for (auto iter = mPendingRestyles.Iter(); !iter.Done(); iter.Next()) {
auto element = static_cast<dom::Element*>(iter.Key());
RestyleTracker::RestyleData* data = iter.Data();
// Only collect the entries that actually need restyling by us (and
// haven't, for example, already been restyled).
// It's important to not mess with the flags on entries not in our
// document.
if (element->GetComposedDoc() != Document() ||
!element->HasFlag(RestyleBit())) {
LOG_RESTYLE("skipping pending restyle %s, already restyled or no "
"longer in the document",
FrameTagToString(element).get());
continue;
}
NS_ASSERTION(
!element->HasFlag(RootBit()) ||
// Maybe we're just not reachable via the frame tree?
(element->GetFlattenedTreeParent() &&
(!element->GetFlattenedTreeParent()->GetPrimaryFrame() ||
element->GetFlattenedTreeParent()->GetPrimaryFrame()->IsLeaf() ||
element->GetComposedDoc()->GetShell()->FrameManager()
->GetDisplayContentsStyleFor(element))) ||
// Or not reachable due to an async reinsert we have
// pending? If so, we'll have a reframe hint around.
// That incidentally makes it safe that we still have
// the bit, since any descendants that didn't get added
// to the roots list because we had the bits will be
// completely restyled in a moment.
(data->mChangeHint & nsChangeHint_ReconstructFrame),
"Why did this not get handled while processing mRestyleRoots?");
// Unset the restyle bits now, so if they get readded later as we
// process we won't clobber that adding of the bit.
element->UnsetFlags(RestyleBit() |
RootBit() |
ConditionalDescendantsBit());
restyle->mElement = element;
restyle->mRestyleHint = data->mRestyleHint;
restyle->mChangeHint = data->mChangeHint;
// We can move data since we'll be clearing mPendingRestyles after
// we finish enumerating it.
restyle->mRestyleHintData = Move(data->mRestyleHintData);
#if defined(MOZ_ENABLE_PROFILER_SPS)
restyle->mBacktrace = Move(data->mBacktrace);
#endif
#ifdef RESTYLE_LOGGING
count++;
#endif
// Increment to the next slot in the array
restyle++;
}
RestyleEnumerateData* lastRestyle = restyle;
// Clear the hashtable now that we don't need it anymore
mPendingRestyles.Clear();
#ifdef RESTYLE_LOGGING
uint32_t index = 0;
#endif
for (RestyleEnumerateData* currentRestyle = restylesToProcess;
currentRestyle != lastRestyle;
++currentRestyle) {
LOG_RESTYLE("processing pending restyle %s at index %d/%d",
FrameTagToString(currentRestyle->mElement).get(),
index++, count);
LOG_RESTYLE_INDENT();
#if defined(MOZ_ENABLE_PROFILER_SPS)
Maybe<GeckoProfilerTracingRAII> profilerRAII;
if (profiler_feature_active("restyle")) {
profilerRAII.emplace("Paint", "Styles", Move(currentRestyle->mBacktrace));
}
#endif
if (isTimelineRecording) {
timelines->AddMarkerForDocShell(docShell, Move(
MakeUnique<RestyleTimelineMarker>(
currentRestyle->mRestyleHint, MarkerTracingType::START)));
}
ProcessOneRestyle(currentRestyle->mElement,
currentRestyle->mRestyleHint,
currentRestyle->mChangeHint,
currentRestyle->mRestyleHintData);
if (isTimelineRecording) {
timelines->AddMarkerForDocShell(docShell, Move(
MakeUnique<RestyleTimelineMarker>(
currentRestyle->mRestyleHint, MarkerTracingType::END)));
}
}
}
}
}
// mPendingRestyles is now empty.
mHaveSelectors = false;
mRestyleManager->EndProcessingRestyles();
}
bool
RestyleTracker::GetRestyleData(Element* aElement, nsAutoPtr<RestyleData>& aData)
{
NS_PRECONDITION(aElement->GetComposedDoc() == Document(),
"Unexpected document; this will lead to incorrect behavior!");
if (!aElement->HasFlag(RestyleBit())) {
NS_ASSERTION(!aElement->HasFlag(RootBit()), "Bogus root bit?");
return false;
}
mPendingRestyles.RemoveAndForget(aElement, aData);
NS_ASSERTION(aData.get(), "Must have data if restyle bit is set");
if (aData->mRestyleHint & eRestyle_LaterSiblings) {
// Someone readded the eRestyle_LaterSiblings hint for this
// element. Leave it around for now, but remove the other restyle
// hints and the change hint for it. Also unset its root bit,
// since it's no longer a root with the new restyle data.
// During a normal restyle, we should have already processed the
// mDescendants array the last time we processed the restyle
// for this element. But in RebuildAllStyleData, we don't initially
// expand out eRestyle_LaterSiblings, so we can get in here the
// first time we need to process a restyle for this element. In that
// case, it's fine for us to have a non-empty mDescendants, since
// we know that RebuildAllStyleData adds eRestyle_ForceDescendants
// and we're guaranteed we'll restyle the entire tree.
NS_ASSERTION(mRestyleManager->InRebuildAllStyleData() ||
aData->mDescendants.IsEmpty(),
"expected descendants to be handled by now");
RestyleData* newData = new RestyleData;
newData->mChangeHint = nsChangeHint(0);
newData->mRestyleHint = eRestyle_LaterSiblings;
mPendingRestyles.Put(aElement, newData);
aElement->UnsetFlags(RootBit());
aData->mRestyleHint =
nsRestyleHint(aData->mRestyleHint & ~eRestyle_LaterSiblings);
} else {
aElement->UnsetFlags(mRestyleBits);
}
return true;
}
void
RestyleTracker::AddRestyleRootsIfAwaitingRestyle(
const nsTArray<RefPtr<Element>>& aElements)
{
// The RestyleData for a given element has stored in mDescendants
// the list of descendants we need to end up restyling. Since we
// won't necessarily end up restyling them, due to the restyle
// process finishing early (see how eRestyleResult_Stop is handled
// in ElementRestyler::Restyle), we add them to the list of restyle
// roots to handle the next time around the
// RestyleTracker::DoProcessRestyles loop.
//
// Note that aElements must maintain the same invariant
// that mRestyleRoots does, i.e. that ancestors appear after descendants.
// Since we call AddRestyleRootsIfAwaitingRestyle only after we have
// removed the restyle root we are currently processing from the end of
// mRestyleRoots, and the only elements we get here in aElements are
// descendants of that restyle root, we are safe to simply append to the
// end of mRestyleRoots to maintain its invariant.
for (size_t i = 0; i < aElements.Length(); i++) {
Element* element = aElements[i];
if (element->HasFlag(RestyleBit())) {
mRestyleRoots.AppendElement(element);
}
}
}
void
RestyleTracker::ClearSelectors()
{
if (!mHaveSelectors) {
return;
}
for (auto it = mPendingRestyles.Iter(); !it.Done(); it.Next()) {
RestyleData* data = it.Data();
if (data->mRestyleHint & eRestyle_SomeDescendants) {
data->mRestyleHint =
(data->mRestyleHint & ~eRestyle_SomeDescendants) | eRestyle_Subtree;
data->mRestyleHintData.mSelectorsForDescendants.Clear();
} else {
MOZ_ASSERT(data->mRestyleHintData.mSelectorsForDescendants.IsEmpty());
}
}
mHaveSelectors = false;
}
} // namespace mozilla
