C++ TimeDuration类代码示例

void TableTicker::InplaceTick(TickSample* sample)
{
  ThreadProfile& currThreadProfile = *sample->threadProfile;

  PseudoStack* stack = currThreadProfile.GetPseudoStack();
  bool recordSample = true;

  /* Don't process the PeudoStack's markers or honour jankOnly if we're
     immediately sampling the current thread. */
  if (!sample->isSamplingCurrentThread) {
    // Marker(s) come before the sample
    ProfilerMarkerLinkedList* pendingMarkersList = stack->getPendingMarkers();
    while (pendingMarkersList && pendingMarkersList->peek()) {
      ProfilerMarker* marker = pendingMarkersList->popHead();
      stack->addStoredMarker(marker);
      currThreadProfile.addTag(ProfileEntry('m', marker));
    }
    stack->updateGeneration(currThreadProfile.GetGenerationID());

    if (mJankOnly) {
      // if we are on a different event we can discard any temporary samples
      // we've kept around
      if (sLastSampledEventGeneration != sCurrentEventGeneration) {
        // XXX: we also probably want to add an entry to the profile to help
        // distinguish which samples are part of the same event. That, or record
        // the event generation in each sample
        currThreadProfile.erase();
      }
      sLastSampledEventGeneration = sCurrentEventGeneration;

      recordSample = false;
      // only record the events when we have a we haven't seen a tracer event for 100ms
      if (!sLastTracerEvent.IsNull()) {
        TimeDuration delta = sample->timestamp - sLastTracerEvent;
        if (delta.ToMilliseconds() > 100.0) {
            recordSample = true;
        }
      }
    }
  }

#if defined(USE_NS_STACKWALK) || defined(USE_EHABI_STACKWALK)
  if (mUseStackWalk) {
    doNativeBacktrace(currThreadProfile, sample);
  } else {
    doSampleStackTrace(stack, currThreadProfile, mAddLeafAddresses ? sample : nullptr);
  }
#else
  doSampleStackTrace(stack, currThreadProfile, mAddLeafAddresses ? sample : nullptr);
#endif

  if (recordSample)
    currThreadProfile.flush();

  if (!sLastTracerEvent.IsNull() && sample && currThreadProfile.IsMainThread()) {
    TimeDuration delta = sample->timestamp - sLastTracerEvent;
    currThreadProfile.addTag(ProfileEntry('r', delta.ToMilliseconds()));
  }

  if (sample) {
    TimeDuration delta = sample->timestamp - sStartTime;
    currThreadProfile.addTag(ProfileEntry('t', delta.ToMilliseconds()));
  }

  if (sLastFrameNumber != sFrameNumber) {
    currThreadProfile.addTag(ProfileEntry('f', sFrameNumber));
    sLastFrameNumber = sFrameNumber;
  }
}

// Returns true if we captured a full interval of data
bool
FPSCounter::CapturedFullInterval(TimeStamp aTimestamp) {
  TimeDuration duration = aTimestamp - mLastInterval;
  return duration.ToSeconds() >= kFpsDumpInterval;
}

void
nsHostResolver::ThreadFunc(void *arg)
{
    LOG(("DNS lookup thread - starting execution.\n"));

    static nsThreadPoolNaming naming;
    naming.SetThreadPoolName(NS_LITERAL_CSTRING("DNS Resolver"));

#if defined(RES_RETRY_ON_FAILURE)
    nsResState rs;
#endif
    nsHostResolver *resolver = (nsHostResolver *)arg;
    nsHostRecord *rec;
    PRAddrInfo *prai = nullptr;
    while (resolver->GetHostToLookup(&rec)) {
        LOG(("DNS lookup thread - Calling getaddrinfo for host [%s].\n",
             rec->host));

        int flags = PR_AI_ADDRCONFIG;
        if (!(rec->flags & RES_CANON_NAME))
            flags |= PR_AI_NOCANONNAME;

        TimeStamp startTime = TimeStamp::Now();
        MOZ_EVENT_TRACER_EXEC(rec, "net::dns::resolve");

        // We need to remove IPv4 records manually
        // because PR_GetAddrInfoByName doesn't support PR_AF_INET6.
        bool disableIPv4 = rec->af == PR_AF_INET6;
        uint16_t af = disableIPv4 ? PR_AF_UNSPEC : rec->af;
        prai = PR_GetAddrInfoByName(rec->host, af, flags);
#if defined(RES_RETRY_ON_FAILURE)
        if (!prai && rs.Reset())
            prai = PR_GetAddrInfoByName(rec->host, af, flags);
#endif

        TimeDuration elapsed = TimeStamp::Now() - startTime;
        uint32_t millis = static_cast<uint32_t>(elapsed.ToMilliseconds());

        // convert error code to nsresult
        nsresult status;
        AddrInfo *ai = nullptr;
        if (prai) {
            const char *cname = nullptr;
            if (rec->flags & RES_CANON_NAME)
                cname = PR_GetCanonNameFromAddrInfo(prai);
            ai = new AddrInfo(rec->host, prai, disableIPv4, cname);
            PR_FreeAddrInfo(prai);
            if (ai->mAddresses.isEmpty()) {
                delete ai;
                ai = nullptr;
            }
        }
        if (ai) {
            status = NS_OK;

            Telemetry::Accumulate(!rec->addr_info_gencnt ?
                                  Telemetry::DNS_LOOKUP_TIME :
                                  Telemetry::DNS_RENEWAL_TIME,
                                  millis);
        }
        else {
            status = NS_ERROR_UNKNOWN_HOST;
            Telemetry::Accumulate(Telemetry::DNS_FAILED_LOOKUP_TIME, millis);
        }

        // OnLookupComplete may release "rec", log before we lose it.
        LOG(("DNS lookup thread - lookup completed for host [%s]: %s.\n",
             rec->host, ai ? "success" : "failure: unknown host"));
        resolver->OnLookupComplete(rec, status, ai);
    }
    NS_RELEASE(resolver);
    LOG(("DNS lookup thread - queue empty, thread finished.\n"));
}

void
nsHostResolver::OnLookupComplete(nsHostRecord *rec, nsresult status, AddrInfo *result)
{
    // get the list of pending callbacks for this lookup, and notify
    // them that the lookup is complete.
    PRCList cbs;
    PR_INIT_CLIST(&cbs);
    {
        MutexAutoLock lock(mLock);

        // grab list of callbacks to notify
        MoveCList(rec->callbacks, cbs);

        // update record fields.  We might have a rec->addr_info already if a
        // previous lookup result expired and we're reresolving it..
        AddrInfo  *old_addr_info;
        {
            MutexAutoLock lock(rec->addr_info_lock);
            old_addr_info = rec->addr_info;
            rec->addr_info = result;
            rec->addr_info_gencnt++;
        }
        delete old_addr_info;

        rec->expiration = TimeStamp::NowLoRes();
        if (result) {
            rec->expiration += mMaxCacheLifetime;
            rec->negative = false;
        }
        else {
            rec->expiration += TimeDuration::FromSeconds(60); /* one minute for negative cache */
            rec->negative = true;
        }
        rec->resolving = false;

        if (rec->usingAnyThread) {
            mActiveAnyThreadCount--;
            rec->usingAnyThread = false;
        }

        if (!mShutdown) {
            // add to mEvictionQ
            PR_APPEND_LINK(rec, &mEvictionQ);
            NS_ADDREF(rec);
            if (mEvictionQSize < mMaxCacheEntries)
                mEvictionQSize++;
            else {
                // remove first element on mEvictionQ
                nsHostRecord *head =
                    static_cast<nsHostRecord *>(PR_LIST_HEAD(&mEvictionQ));
                PR_REMOVE_AND_INIT_LINK(head);
                PL_DHashTableOperate(&mDB, (nsHostKey *) head, PL_DHASH_REMOVE);

                if (!head->negative) {
                    // record the age of the entry upon eviction.
                    TimeDuration age = TimeStamp::NowLoRes() -
                                       (head->expiration - mMaxCacheLifetime);
                    Telemetry::Accumulate(Telemetry::DNS_CLEANUP_AGE,
                                          static_cast<uint32_t>(age.ToSeconds() / 60));
                }

                // release reference to rec owned by mEvictionQ
                NS_RELEASE(head);
            }
        }
    }

    MOZ_EVENT_TRACER_DONE(rec, "net::dns::resolve");

    if (!PR_CLIST_IS_EMPTY(&cbs)) {
        PRCList *node = cbs.next;
        while (node != &cbs) {
            nsResolveHostCallback *callback =
                static_cast<nsResolveHostCallback *>(node);
            node = node->next;
            callback->OnLookupComplete(this, rec, status);
            // NOTE: callback must not be dereferenced after this point!!
        }
    }

    NS_RELEASE(rec);
}

gfxFontEntry*
gfxPlatformFontList::SystemFindFontForChar(uint32_t aCh, uint32_t aNextCh,
                                           int32_t aRunScript,
                                           const gfxFontStyle* aStyle)
 {
    gfxFontEntry* fontEntry = nullptr;

    // is codepoint with no matching font? return null immediately
    if (mCodepointsWithNoFonts.test(aCh)) {
        return nullptr;
    }

    // Try to short-circuit font fallback for U+FFFD, used to represent
    // encoding errors: just use cached family from last time U+FFFD was seen.
    // This helps speed up pages with lots of encoding errors, binary-as-text,
    // etc.
    if (aCh == 0xFFFD && mReplacementCharFallbackFamily) {
        bool needsBold;  // ignored in the system fallback case

        fontEntry =
            mReplacementCharFallbackFamily->FindFontForStyle(*aStyle,
                                                             needsBold);

        // this should never fail, as we must have found U+FFFD in order to set
        // mReplacementCharFallbackFamily at all, but better play it safe
        if (fontEntry && fontEntry->HasCharacter(aCh)) {
            return fontEntry;
        }
    }

    TimeStamp start = TimeStamp::Now();

    // search commonly available fonts
    bool common = true;
    gfxFontFamily *fallbackFamily = nullptr;
    fontEntry = CommonFontFallback(aCh, aNextCh, aRunScript, aStyle,
                                   &fallbackFamily);
 
    // if didn't find a font, do system-wide fallback (except for specials)
    uint32_t cmapCount = 0;
    if (!fontEntry) {
        common = false;
        fontEntry = GlobalFontFallback(aCh, aRunScript, aStyle, cmapCount,
                                       &fallbackFamily);
    }
    TimeDuration elapsed = TimeStamp::Now() - start;

    PRLogModuleInfo *log = gfxPlatform::GetLog(eGfxLog_textrun);

    if (MOZ_UNLIKELY(MOZ_LOG_TEST(log, LogLevel::Warning))) {
        uint32_t unicodeRange = FindCharUnicodeRange(aCh);
        int32_t script = mozilla::unicode::GetScriptCode(aCh);
        MOZ_LOG(log, LogLevel::Warning,\
               ("(textrun-systemfallback-%s) char: u+%6.6x "
                 "unicode-range: %d script: %d match: [%s]"
                " time: %dus cmaps: %d\n",
                (common ? "common" : "global"), aCh,
                 unicodeRange, script,
                (fontEntry ? NS_ConvertUTF16toUTF8(fontEntry->Name()).get() :
                    "<none>"),
                int32_t(elapsed.ToMicroseconds()),
                cmapCount));
    }

    // no match? add to set of non-matching codepoints
    if (!fontEntry) {
        mCodepointsWithNoFonts.set(aCh);
    } else if (aCh == 0xFFFD && fontEntry && fallbackFamily) {
        mReplacementCharFallbackFamily = fallbackFamily;
    }
 
    // track system fallback time
    static bool first = true;
    int32_t intElapsed = int32_t(first ? elapsed.ToMilliseconds() :
                                         elapsed.ToMicroseconds());
    Telemetry::Accumulate((first ? Telemetry::SYSTEM_FONT_FALLBACK_FIRST :
                                   Telemetry::SYSTEM_FONT_FALLBACK),
                          intElapsed);
    first = false;

    // track the script for which fallback occurred (incremented one make it
    // 1-based)
    Telemetry::Accumulate(Telemetry::SYSTEM_FONT_FALLBACK_SCRIPT, aRunScript + 1);

    return fontEntry;
}

void nsTimerImpl::Fire()
{
  if (mCanceled)
    return;

  TimeStamp now = TimeStamp::Now();
#ifdef DEBUG_TIMERS
  if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
    TimeDuration   a = now - mStart; // actual delay in intervals
    TimeDuration   b = TimeDuration::FromMilliseconds(mDelay); // expected delay in intervals
    TimeDuration   delta = (a > b) ? a - b : b - a;
    PRUint32       d = delta.ToMilliseconds(); // delta in ms
    sDeltaSum += d;
    sDeltaSumSquared += double(d) * double(d);
    sDeltaNum++;

    PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p] expected delay time %4ums\n", this, mDelay));
    PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p] actual delay time   %fms\n", this, a.ToMilliseconds()));
    PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p] (mType is %d)       -------\n", this, mType));
    PR_LOG(gTimerLog, PR_LOG_DEBUG, ("[this=%p]     delta           %4dms\n", this, (a > b) ? (PRInt32)d : -(PRInt32)d));

    mStart = mStart2;
    mStart2 = TimeStamp();
  }
#endif

  TimeStamp timeout = mTimeout;
  if (IsRepeatingPrecisely()) {
    // Precise repeating timers advance mTimeout by mDelay without fail before
    // calling Fire().
    timeout -= TimeDuration::FromMilliseconds(mDelay);
  }
  if (gThread)
    gThread->UpdateFilter(mDelay, timeout, now);

  if (mCallbackType == CALLBACK_TYPE_INTERFACE)
    mTimerCallbackWhileFiring = mCallback.i;
  mFiring = PR_TRUE;
  
  // Handle callbacks that re-init the timer, but avoid leaking.
  // See bug 330128.
  CallbackUnion callback = mCallback;
  PRUintn callbackType = mCallbackType;
  if (callbackType == CALLBACK_TYPE_INTERFACE)
    NS_ADDREF(callback.i);
  else if (callbackType == CALLBACK_TYPE_OBSERVER)
    NS_ADDREF(callback.o);
  ReleaseCallback();

  switch (callbackType) {
    case CALLBACK_TYPE_FUNC:
      callback.c(this, mClosure);
      break;
    case CALLBACK_TYPE_INTERFACE:
      callback.i->Notify(this);
      break;
    case CALLBACK_TYPE_OBSERVER:
      callback.o->Observe(static_cast<nsITimer*>(this),
                          NS_TIMER_CALLBACK_TOPIC,
                          nsnull);
      break;
    default:;
  }

  // If the callback didn't re-init the timer, and it's not a one-shot timer,
  // restore the callback state.
  if (mCallbackType == CALLBACK_TYPE_UNKNOWN &&
      mType != TYPE_ONE_SHOT && !mCanceled) {
    mCallback = callback;
    mCallbackType = callbackType;
  } else {
    // The timer was a one-shot, or the callback was reinitialized.
    if (callbackType == CALLBACK_TYPE_INTERFACE)
      NS_RELEASE(callback.i);
    else if (callbackType == CALLBACK_TYPE_OBSERVER)
      NS_RELEASE(callback.o);
  }

  mFiring = PR_FALSE;
  mTimerCallbackWhileFiring = nsnull;

#ifdef DEBUG_TIMERS
  if (PR_LOG_TEST(gTimerLog, PR_LOG_DEBUG)) {
    PR_LOG(gTimerLog, PR_LOG_DEBUG,
           ("[this=%p] Took %fms to fire timer callback\n",
            this, (TimeStamp::Now() - now).ToMilliseconds()));
  }
#endif

  // Reschedule repeating timers, except REPEATING_PRECISE which already did
  // that in PostTimerEvent, but make sure that we aren't armed already (which
  // can happen if the callback reinitialized the timer).
  if (IsRepeating() && mType != TYPE_REPEATING_PRECISE && !mArmed) {
    if (mType == TYPE_REPEATING_SLACK)
      SetDelayInternal(mDelay); // force mTimeout to be recomputed.  For
                                // REPEATING_PRECISE_CAN_SKIP timers this has
                                // already happened.
    if (gThread)
      gThread->AddTimer(this);
  }
//.........这里部分代码省略.........

void Enemy::NormalAnimator::update(TimeDuration dt,
								   gr::Model<gr::Transform2>& model)
{
	model.transform().rotation() += angularVelocity * dt.toSecs();
}

void
CompositorParent::CompositeToTarget(DrawTarget* aTarget, const nsIntRect* aRect)
{
  profiler_tracing("Paint", "Composite", TRACING_INTERVAL_START);
  PROFILER_LABEL("CompositorParent", "Composite",
    js::ProfileEntry::Category::GRAPHICS);

  MOZ_ASSERT(IsInCompositorThread(),
             "Composite can only be called on the compositor thread");

#ifdef COMPOSITOR_PERFORMANCE_WARNING
  TimeDuration scheduleDelta = TimeStamp::Now() - mExpectedComposeStartTime;
  if (scheduleDelta > TimeDuration::FromMilliseconds(2) ||
      scheduleDelta < TimeDuration::FromMilliseconds(-2)) {
    printf_stderr("Compositor: Compose starting off schedule by %4.1f ms\n",
                  scheduleDelta.ToMilliseconds());
  }
#endif

  mLastCompose = TimeStamp::Now();

  if (!CanComposite()) {
    DidComposite();
    return;
  }

  AutoResolveRefLayers resolve(mCompositionManager);

  if (aTarget) {
    mLayerManager->BeginTransactionWithDrawTarget(aTarget, *aRect);
  } else {
    mLayerManager->BeginTransaction();
  }

  if (mForceCompositionTask && !mOverrideComposeReadiness) {
    if (mCompositionManager->ReadyForCompose()) {
      mForceCompositionTask->Cancel();
      mForceCompositionTask = nullptr;
    } else {
      return;
    }
  }

  TimeStamp time = mIsTesting ? mTestTime : mLastCompose;
  bool requestNextFrame = mCompositionManager->TransformShadowTree(time);
  if (requestNextFrame) {
    ScheduleComposition();
  }

  RenderTraceLayers(mLayerManager->GetRoot(), "0000");

  mCompositionManager->ComputeRotation();

#ifdef MOZ_DUMP_PAINTING
  static bool gDumpCompositorTree = false;
  if (gDumpCompositorTree) {
    printf_stderr("Painting --- compositing layer tree:\n");
    mLayerManager->Dump();
  }
#endif
  mLayerManager->SetDebugOverlayWantsNextFrame(false);
  mLayerManager->EndEmptyTransaction();

  if (!aTarget) {
    DidComposite();
  }

  if (mLayerManager->DebugOverlayWantsNextFrame()) {
    ScheduleComposition();
  }

#ifdef COMPOSITOR_PERFORMANCE_WARNING
  TimeDuration executionTime = TimeStamp::Now() - mLastCompose;
  TimeDuration frameBudget = TimeDuration::FromMilliseconds(15);
  int32_t frameRate = CalculateCompositionFrameRate();
  if (frameRate > 0) {
    frameBudget = TimeDuration::FromSeconds(1.0 / frameRate);
  }
  if (executionTime > frameBudget) {
    printf_stderr("Compositor: Composite execution took %4.1f ms\n",
                  executionTime.ToMilliseconds());
  }
#endif

  // 0 -> Full-tilt composite
  if (gfxPrefs::LayersCompositionFrameRate() == 0
    || mLayerManager->GetCompositor()->GetDiagnosticTypes() & DiagnosticTypes::FLASH_BORDERS) {
    // Special full-tilt composite mode for performance testing
    ScheduleComposition();
  }

  profiler_tracing("Paint", "Composite", TRACING_INTERVAL_END);
}

int64_t AsyncLatencyLogger::GetTimeStamp()
{
  TimeDuration t = TimeStamp::Now() - mStart;
  return t.ToMilliseconds();
}

 inline void sleep(TimeDuration const& rel_time)
 {
     interruptible_wait(detail::pin_to_zero(rel_time.total_milliseconds()));
 }

NS_IMETHODIMP
CVE_2014_1482_seamonkey2_9_RasterImage::Draw(gfxContext *aContext,
                  gfxPattern::GraphicsFilter aFilter,
                  const gfxMatrix &aUserSpaceToImageSpace,
                  const gfxRect &aFill,
                  const nsIntRect &aSubimage,
                  const nsIntSize& /*aViewportSize - ignored*/,
                  PRUint32 aFlags)
{
  if (mError)
    return NS_ERROR_FAILURE;

  // Disallowed in the API
  if (mInDecoder && (aFlags & imgIContainer::FLAG_SYNC_DECODE))
    return NS_ERROR_FAILURE;

  // Illegal -- you can't draw with non-default decode flags.
  // (Disabling colorspace conversion might make sense to allow, but
  // we don't currently.)
  if ((aFlags & DECODE_FLAGS_MASK) != DECODE_FLAGS_DEFAULT)
    return NS_ERROR_FAILURE;

  NS_ENSURE_ARG_POINTER(aContext);

  // We can only draw with the default decode flags
  if (mFrameDecodeFlags != DECODE_FLAGS_DEFAULT) {
    if (!CanForciblyDiscard())
      return NS_ERROR_NOT_AVAILABLE;
    ForceDiscard();

    mFrameDecodeFlags = DECODE_FLAGS_DEFAULT;
  }

  // We use !mDecoded && mHasSourceData to mean discarded.
  if (!mDecoded && mHasSourceData) {
      mDrawStartTime = TimeStamp::Now();
  }

  // If a synchronous draw is requested, flush anything that might be sitting around
  if (aFlags & FLAG_SYNC_DECODE) {
    nsresult rv = SyncDecode();
    NS_ENSURE_SUCCESS(rv, rv);
  }

  imgFrame *frame = GetCurrentDrawableImgFrame();
  if (!frame) {
    return NS_OK; // Getting the frame (above) touches the image and kicks off decoding
  }

  nsIntRect framerect = frame->GetRect();
  nsIntMargin padding(framerect.x, framerect.y, 
                      mSize.width - framerect.XMost(),
                      mSize.height - framerect.YMost());

  frame->Draw(aContext, aFilter, aUserSpaceToImageSpace, aFill, padding, aSubimage);

  if (mDecoded && !mDrawStartTime.IsNull()) {
      TimeDuration drawLatency = TimeStamp::Now() - mDrawStartTime;
      Telemetry::Accumulate(Telemetry::IMAGE_DECODE_ON_DRAW_LATENCY, PRInt32(drawLatency.ToMicroseconds()));
      // clear the value of mDrawStartTime
      mDrawStartTime = TimeStamp();
  }
  return NS_OK;
}

FrameAnimator::RefreshResult
FrameAnimator::AdvanceFrame(TimeStamp aTime)
{
  NS_ASSERTION(aTime <= TimeStamp::Now(),
               "Given time appears to be in the future");

  uint32_t currentFrameIndex = mCurrentAnimationFrameIndex;
  uint32_t nextFrameIndex = currentFrameIndex + 1;
  uint32_t timeout = 0;

  RefreshResult ret;

  // If we're done decoding, we know we've got everything we're going to get.
  // If we aren't, we only display fully-downloaded frames; everything else
  // gets delayed.
  bool canDisplay = mDoneDecoding ||
                    (mFrameBlender.RawGetFrame(nextFrameIndex) &&
                     mFrameBlender.RawGetFrame(nextFrameIndex)->ImageComplete());

  if (!canDisplay) {
    // Uh oh, the frame we want to show is currently being decoded (partial)
    // Wait until the next refresh driver tick and try again
    return ret;
  } else {
    // If we're done decoding the next frame, go ahead and display it now and
    // reinit with the next frame's delay time.
    if (mFrameBlender.GetNumFrames() == nextFrameIndex) {
      // End of Animation, unless we are looping forever

      // If animation mode is "loop once", it's time to stop animating
      if (mAnimationMode == imgIContainer::kLoopOnceAnimMode || mLoopCount == 0) {
        ret.animationFinished = true;
      }

      nextFrameIndex = 0;

      if (mLoopCount > 0) {
        mLoopCount--;
      }

      // If we're done, exit early.
      if (ret.animationFinished) {
        return ret;
      }
    }

    timeout = mFrameBlender.GetFrame(nextFrameIndex)->GetTimeout();
  }

  // Bad data
  if (!(timeout > 0)) {
    ret.animationFinished = true;
    ret.error = true;
  }

  if (nextFrameIndex == 0) {
    ret.dirtyRect = mFirstFrameRefreshArea;
  } else {
    // Change frame
    if (!mFrameBlender.DoBlend(&ret.dirtyRect, currentFrameIndex, nextFrameIndex)) {
      // something went wrong, move on to next
      NS_WARNING("FrameAnimator::AdvanceFrame(): Compositing of frame failed");
      mFrameBlender.RawGetFrame(nextFrameIndex)->SetCompositingFailed(true);
      mCurrentAnimationFrameTime = GetCurrentImgFrameEndTime();
      mCurrentAnimationFrameIndex = nextFrameIndex;

      ret.error = true;
      return ret;
    }

    mFrameBlender.RawGetFrame(nextFrameIndex)->SetCompositingFailed(false);
  }

  mCurrentAnimationFrameTime = GetCurrentImgFrameEndTime();

  // If we can get closer to the current time by a multiple of the image's loop
  // time, we should.
  uint32_t loopTime = GetSingleLoopTime();
  if (loopTime > 0) {
    TimeDuration delay = aTime - mCurrentAnimationFrameTime;
    if (delay.ToMilliseconds() > loopTime) {
      // Explicitly use integer division to get the floor of the number of
      // loops.
      uint32_t loops = static_cast<uint32_t>(delay.ToMilliseconds()) / loopTime;
      mCurrentAnimationFrameTime += TimeDuration::FromMilliseconds(loops * loopTime);
    }
  }

  // Set currentAnimationFrameIndex at the last possible moment
  mCurrentAnimationFrameIndex = nextFrameIndex;

  // If we're here, we successfully advanced the frame.
  ret.frameAdvanced = true;

  return ret;
}

void
nsTimerImpl::Fire()
{
  if (mCanceled) {
    return;
  }

  PROFILER_LABEL("Timer", "Fire",
                 js::ProfileEntry::Category::OTHER);

  TimeStamp now = TimeStamp::Now();
  if (MOZ_LOG_TEST(GetTimerLog(), LogLevel::Debug)) {
    TimeDuration   a = now - mStart; // actual delay in intervals
    TimeDuration   b = TimeDuration::FromMilliseconds(mDelay); // expected delay in intervals
    TimeDuration   delta = (a > b) ? a - b : b - a;
    uint32_t       d = delta.ToMilliseconds(); // delta in ms
    sDeltaSum += d;
    sDeltaSumSquared += double(d) * double(d);
    sDeltaNum++;

    MOZ_LOG(GetTimerLog(), LogLevel::Debug,
           ("[this=%p] expected delay time %4ums\n", this, mDelay));
    MOZ_LOG(GetTimerLog(), LogLevel::Debug,
           ("[this=%p] actual delay time   %fms\n", this,
            a.ToMilliseconds()));
    MOZ_LOG(GetTimerLog(), LogLevel::Debug,
           ("[this=%p] (mType is %d)       -------\n", this, mType));
    MOZ_LOG(GetTimerLog(), LogLevel::Debug,
           ("[this=%p]     delta           %4dms\n",
            this, (a > b) ? (int32_t)d : -(int32_t)d));

    mStart = mStart2;
    mStart2 = TimeStamp();
  }

  TimeStamp timeout = mTimeout;
  if (IsRepeatingPrecisely()) {
    // Precise repeating timers advance mTimeout by mDelay without fail before
    // calling Fire().
    timeout -= TimeDuration::FromMilliseconds(mDelay);
  }

  if (mCallbackType == CallbackType::Interface) {
    mTimerCallbackWhileFiring = mCallback.i;
  }
  mFiring = true;

  // Handle callbacks that re-init the timer, but avoid leaking.
  // See bug 330128.
  CallbackUnion callback = mCallback;
  CallbackType callbackType = mCallbackType;
  if (callbackType == CallbackType::Interface) {
    NS_ADDREF(callback.i);
  } else if (callbackType == CallbackType::Observer) {
    NS_ADDREF(callback.o);
  }
  ReleaseCallback();

  if (MOZ_LOG_TEST(GetTimerFiringsLog(), LogLevel::Debug)) {
    LogFiring(callbackType, callback);
  }

  switch (callbackType) {
    case CallbackType::Function:
      callback.c(this, mClosure);
      break;
    case CallbackType::Interface:
      callback.i->Notify(this);
      break;
    case CallbackType::Observer:
      callback.o->Observe(static_cast<nsITimer*>(this),
                          NS_TIMER_CALLBACK_TOPIC,
                          nullptr);
      break;
    default:
      ;
  }

  // If the callback didn't re-init the timer, and it's not a one-shot timer,
  // restore the callback state.
  if (mCallbackType == CallbackType::Unknown &&
      mType != TYPE_ONE_SHOT && !mCanceled) {
    mCallback = callback;
    mCallbackType = callbackType;
  } else {
    // The timer was a one-shot, or the callback was reinitialized.
    if (callbackType == CallbackType::Interface) {
      NS_RELEASE(callback.i);
    } else if (callbackType == CallbackType::Observer) {
      NS_RELEASE(callback.o);
    }
  }

  mFiring = false;
  mTimerCallbackWhileFiring = nullptr;

  MOZ_LOG(GetTimerLog(), LogLevel::Debug,
         ("[this=%p] Took %fms to fire timer callback\n",
          this, (TimeStamp::Now() - now).ToMilliseconds()));

//.........这里部分代码省略.........

void
VRDisplayHost::NotifyVSync()
{
  /**
   * We will trigger a new frame immediately after a successful frame texture
   * submission.  If content fails to call VRDisplay.submitFrame after
   * kVRDisplayRAFMaxDuration milliseconds has elapsed since the last
   * VRDisplay.requestAnimationFrame, we act as a "watchdog" and kick-off
   * a new VRDisplay.requestAnimationFrame to avoid a render loop stall and
   * to give content a chance to recover.
   *
   * If the lower level VR platform API's are rejecting submitted frames,
   * such as when the Oculus "Health and Safety Warning" is displayed,
   * we will not kick off the next frame immediately after VRDisplay.submitFrame
   * as it would result in an unthrottled render loop that would free run at
   * potentially extreme frame rates.  To ensure that content has a chance to
   * resume its presentation when the frames are accepted once again, we rely
   * on this "watchdog" to act as a VR refresh driver cycling at a rate defined
   * by kVRDisplayRAFMaxDuration.
   *
   * kVRDisplayRAFMaxDuration is the number of milliseconds since last frame
   * start before triggering a new frame.  When content is failing to submit
   * frames on time or the lower level VR platform API's are rejecting frames,
   * kVRDisplayRAFMaxDuration determines the rate at which RAF callbacks
   * will be called.
   *
   * This number must be larger than the slowest expected frame time during
   * normal VR presentation, but small enough not to break content that
   * makes assumptions of reasonably minimal VSync rate.
   *
   * The slowest expected refresh rate for a VR display currently is an
   * Oculus CV1 when ASW (Asynchronous Space Warp) is enabled, at 45hz.
   * A kVRDisplayRAFMaxDuration value of 50 milliseconds results in a 20hz
   * rate, which avoids inadvertent triggering of the watchdog during
   * Oculus ASW even if every second frame is dropped.
   */
  const double kVRDisplayRAFMaxDuration = 50;

  bool bShouldStartFrame = false;

  if (mDisplayInfo.mPresentingGroups == 0) {
    // If this display isn't presenting, refresh the sensors and trigger
    // VRDisplay.requestAnimationFrame at the normal 2d display refresh rate.
    bShouldStartFrame = true;
  } else {
    // If content fails to call VRDisplay.submitFrame, we must eventually
    // time-out and trigger a new frame.
    if (mLastFrameStart.IsNull()) {
      bShouldStartFrame = true;
    } else {
      TimeDuration duration = TimeStamp::Now() - mLastFrameStart;
      if (duration.ToMilliseconds() > kVRDisplayRAFMaxDuration) {
        bShouldStartFrame = true;
      }
    }
  }

  if (bShouldStartFrame) {
    VRManager *vm = VRManager::Get();
    MOZ_ASSERT(vm);
    vm->NotifyVRVsync(mDisplayInfo.mDisplayID);
  }
}

RasterImage::Draw(gfxContext* aContext,
                  const IntSize& aSize,
                  const ImageRegion& aRegion,
                  uint32_t aWhichFrame,
                  SamplingFilter aSamplingFilter,
                  const Maybe<SVGImageContext>& /*aSVGContext - ignored*/,
                  uint32_t aFlags,
                  float aOpacity)
{
  if (aWhichFrame > FRAME_MAX_VALUE) {
    return DrawResult::BAD_ARGS;
  }

  if (mError) {
    return DrawResult::BAD_IMAGE;
  }

  // Illegal -- you can't draw with non-default decode flags.
  // (Disabling colorspace conversion might make sense to allow, but
  // we don't currently.)
  if (ToSurfaceFlags(aFlags) != DefaultSurfaceFlags()) {
    return DrawResult::BAD_ARGS;
  }

  if (!aContext) {
    return DrawResult::BAD_ARGS;
  }

  if (IsUnlocked()) {
    SendOnUnlockedDraw(aFlags);
  }


  // If we're not using SamplingFilter::GOOD, we shouldn't high-quality scale or
  // downscale during decode.
  uint32_t flags = aSamplingFilter == SamplingFilter::GOOD
                 ? aFlags
                 : aFlags & ~FLAG_HIGH_QUALITY_SCALING;

  DrawableSurface surface =
    LookupFrame(aSize, flags, ToPlaybackType(aWhichFrame));
  if (!surface) {
    // Getting the frame (above) touches the image and kicks off decoding.
    if (mDrawStartTime.IsNull()) {
      mDrawStartTime = TimeStamp::Now();
    }
    return DrawResult::NOT_READY;
  }

  bool shouldRecordTelemetry = !mDrawStartTime.IsNull() &&
                               surface->IsFinished();

  auto result = DrawInternal(Move(surface), aContext, aSize,
                             aRegion, aSamplingFilter, flags, aOpacity);

  if (shouldRecordTelemetry) {
      TimeDuration drawLatency = TimeStamp::Now() - mDrawStartTime;
      Telemetry::Accumulate(Telemetry::IMAGE_DECODE_ON_DRAW_LATENCY,
                            int32_t(drawLatency.ToMicroseconds()));
      mDrawStartTime = TimeStamp();
  }

  return result;
}