Bug 197561

Summary: Implement "shared" compositing layers, allowing overlap layers to paint into the backing store of another layer
Product: WebKit Reporter: Simon Fraser (smfr) <simon.fraser>
Component: CompositingAssignee: Simon Fraser (smfr) <simon.fraser>
Status: RESOLVED FIXED    
Severity: Normal CC: cathiechen, ews-watchlist, koivisto, mcatanzaro, rniwa, ryanhaddad, simon.fraser, thorton, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on: 197562, 197564, 197565, 197595, 197692, 197694, 197766, 197768, 197776, 197783, 197811, 197824    
Bug Blocks:    
Attachments:
Description Flags
Patch
none
Archive of layout-test-results from ews101 for mac-highsierra
none
Archive of layout-test-results from ews106 for mac-highsierra-wk2
none
Archive of layout-test-results from ews114 for mac-highsierra
none
Archive of layout-test-results from ews214 for win-future
none
Archive of layout-test-results from ews126 for ios-simulator-wk2
none
Patch
none
Patch
none
Patch
none
Patch
none
Archive of layout-test-results from ews101 for mac-highsierra
none
Archive of layout-test-results from ews117 for mac-highsierra
none
Archive of layout-test-results from ews107 for mac-highsierra-wk2
none
Archive of layout-test-results from ews123 for ios-simulator-wk2
none
Archive of layout-test-results from ews210 for win-future
none
Patch
none
Archive of layout-test-results from ews122 for ios-simulator-wk2
none
Archive of layout-test-results from ews115 for mac-highsierra
none
Patch
none
Patch
koivisto: review+, ews-watchlist: commit-queue-
Archive of layout-test-results from ews112 for mac-highsierra
none
Archive of layout-test-results from ews126 for ios-simulator-wk2
none
Archive of layout-test-results from ews210 for win-future none

Simon Fraser (smfr)
Reported 2019-05-03 09:23:18 PDT
An "inclusive" compositing layer is one that can paint a set of other (usually sibling) layers that would otherwise be composited for overlap. They will reduce the amount of backing store, and the need for scrolling tree nodes in some cases.
Attachments
Patch (157.56 KB, patch)
2019-05-04 19:28 PDT, Simon Fraser (smfr)
no flags
Archive of layout-test-results from ews101 for mac-highsierra (3.48 MB, application/zip)
2019-05-04 20:37 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews106 for mac-highsierra-wk2 (2.77 MB, application/zip)
2019-05-04 20:48 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews114 for mac-highsierra (1.62 MB, application/zip)
2019-05-04 21:01 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews214 for win-future (13.43 MB, application/zip)
2019-05-04 21:23 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews126 for ios-simulator-wk2 (2.82 MB, application/zip)
2019-05-04 21:33 PDT, EWS Watchlist
no flags
Patch (168.02 KB, patch)
2019-05-06 10:35 PDT, Simon Fraser (smfr)
no flags
Patch (161.38 KB, patch)
2019-05-06 22:23 PDT, Simon Fraser (smfr)
no flags
Patch (178.87 KB, patch)
2019-05-06 22:27 PDT, Simon Fraser (smfr)
no flags
Patch (178.06 KB, patch)
2019-05-06 22:35 PDT, Simon Fraser (smfr)
no flags
Archive of layout-test-results from ews101 for mac-highsierra (17.22 MB, application/zip)
2019-05-06 23:34 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews117 for mac-highsierra (12.63 MB, application/zip)
2019-05-06 23:52 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews107 for mac-highsierra-wk2 (17.38 MB, application/zip)
2019-05-06 23:57 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews123 for ios-simulator-wk2 (15.18 MB, application/zip)
2019-05-07 00:30 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews210 for win-future (22.65 MB, application/zip)
2019-05-07 09:19 PDT, EWS Watchlist
no flags
Patch (181.93 KB, patch)
2019-05-07 10:57 PDT, Simon Fraser (smfr)
no flags
Archive of layout-test-results from ews122 for ios-simulator-wk2 (8.16 MB, application/zip)
2019-05-07 12:57 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews115 for mac-highsierra (3.86 MB, application/zip)
2019-05-07 13:05 PDT, EWS Watchlist
no flags
Patch (190.62 KB, patch)
2019-05-07 20:51 PDT, Simon Fraser (smfr)
no flags
Patch (189.23 KB, patch)
2019-05-07 21:03 PDT, Simon Fraser (smfr)
koivisto: review+
ews-watchlist: commit-queue-
Archive of layout-test-results from ews112 for mac-highsierra (3.00 MB, application/zip)
2019-05-07 22:53 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews126 for ios-simulator-wk2 (11.94 MB, application/zip)
2019-05-07 23:04 PDT, EWS Watchlist
no flags
Archive of layout-test-results from ews210 for win-future (13.62 MB, application/zip)
2019-05-08 01:44 PDT, EWS Watchlist
no flags
Radar WebKit Bug Importer
Comment 1 2019-05-03 09:23:50 PDT
Simon Fraser (smfr)
Comment 2 2019-05-04 19:28:17 PDT
Simon Fraser (smfr)
Comment 3 2019-05-04 19:35:09 PDT
*** Bug 197594 has been marked as a duplicate of this bug. ***
EWS Watchlist
Comment 4 2019-05-04 20:37:06 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 5 2019-05-04 20:37:08 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 6 2019-05-04 20:48:53 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 7 2019-05-04 20:48:55 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 8 2019-05-04 21:01:53 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 9 2019-05-04 21:01:55 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 10 2019-05-04 21:23:31 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 11 2019-05-04 21:23:33 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 12 2019-05-04 21:33:27 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 13 2019-05-04 21:33:29 PDT Comment hidden (obsolete)
Simon Fraser (smfr)
Comment 14 2019-05-04 21:41:31 PDT
Comment on attachment 369080 [details] Patch Crashes are because traverseUnchangedSubtree() needs to do sharing stuff.
Antti Koivisto
Comment 15 2019-05-06 01:40:35 PDT
Comment on attachment 369080 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=369080&action=review > Source/WebCore/rendering/RenderLayer.cpp:1817 > + RenderLayer* repaintTarget; > + if (includeSelf == IncludeSelf && (repaintTarget = repaintTargetForLayer(*this))) > + return repaintTarget; No reason to leave repaintTarget uninitialized. > Source/WebCore/rendering/RenderLayer.h:818 > + // If non,null, a non-ancestor composited layer that this layer paints into (it is sharing its backing store with this layer). "non-null" > Source/WebCore/rendering/RenderLayer.h:822 > + RenderLayer* sharedLayer() const { return m_sharedLayer; } > + void setSharedLayer(RenderLayer* sharedLayer) { m_sharedLayer = sharedLayer; } > + > + bool paintsIntoSharedLayer() const { return m_sharedLayer; } "Shared layer" does not really describe the feature. I feel it would be clearer to express this in terms of "shared backing" in code. This might be just a matter of renaming and probably also switching to RenderLayerBacking ptrs here. I wonder if there some sort of future refactoring here that actually makes RenderLayerBacking a shared object? > Source/WebCore/rendering/RenderLayer.h:1268 > + // If non,null, a non-ancestor composited layer that this layer paints into. "non-null" > Source/WebCore/rendering/RenderLayerBacking.cpp:264 > + for (auto* layer : m_sharingLayers) > + layer->setSharedLayer(nullptr); This kind of stuff is scary. Layer tree should use WeakPtrs. It would be better to call clearSharingLayers() to avoid duplication. > Source/WebCore/rendering/RenderLayerBacking.cpp:2678 > + for (auto* layer : m_sharingLayers) > + paintOneLayer(*layer, sharingLayerPaintFlags); I suppose region gathering code needs to replicate this logic too. Please file a bug. > Source/WebCore/rendering/RenderLayerBacking.h:398 > + // When this layer is a shared layer, sharing layers other than m_owningLayer are in this list, and paint into our backing store. This is a confusing sentence.
Simon Fraser (smfr)
Comment 16 2019-05-06 09:32:34 PDT
(In reply to Antti Koivisto from comment #15) > Comment on attachment 369080 [details] > Patch > > View in context: > https://bugs.webkit.org/attachment.cgi?id=369080&action=review > > > Source/WebCore/rendering/RenderLayer.cpp:1817 > > + RenderLayer* repaintTarget; > > + if (includeSelf == IncludeSelf && (repaintTarget = repaintTargetForLayer(*this))) > > + return repaintTarget; > > No reason to leave repaintTarget uninitialized. > > > Source/WebCore/rendering/RenderLayer.h:818 > > + // If non,null, a non-ancestor composited layer that this layer paints into (it is sharing its backing store with this layer). > > "non-null" > > > Source/WebCore/rendering/RenderLayer.h:822 > > + RenderLayer* sharedLayer() const { return m_sharedLayer; } > > + void setSharedLayer(RenderLayer* sharedLayer) { m_sharedLayer = sharedLayer; } > > + > > + bool paintsIntoSharedLayer() const { return m_sharedLayer; } > > "Shared layer" does not really describe the feature. I feel it would be > clearer to express this in terms of "shared backing" in code. This might be > just a matter of renaming and probably also switching to RenderLayerBacking > ptrs here. I agree that "shared" isn't too descriptive. Other implementations have called them "inclusive" which has clearer directionality ("inclusive, included") but Zalan didn't like that. I don't want to use RLB pointers because I don't want to introduce a dependency on when backing actually gets created. > I wonder if there some sort of future refactoring here that actually makes > RenderLayerBacking a shared object? Perhaps, though there is still a clear "primary" owner. > > Source/WebCore/rendering/RenderLayer.h:1268 > > + // If non,null, a non-ancestor composited layer that this layer paints into. > > "non-null" > > > Source/WebCore/rendering/RenderLayerBacking.cpp:264 > > + for (auto* layer : m_sharingLayers) > > + layer->setSharedLayer(nullptr); > > This kind of stuff is scary. Layer tree should use WeakPtrs. Will fix. > It would be better to call clearSharingLayers() to avoid duplication. > > > Source/WebCore/rendering/RenderLayerBacking.cpp:2678 > > + for (auto* layer : m_sharingLayers) > > + paintOneLayer(*layer, sharingLayerPaintFlags); > > I suppose region gathering code needs to replicate this logic too. Please > file a bug. Good point. > > Source/WebCore/rendering/RenderLayerBacking.h:398 > > + // When this layer is a shared layer, sharing layers other than m_owningLayer are in this list, and paint into our backing store. > > This is a confusing sentence. Will fix.
Antti Koivisto
Comment 17 2019-05-06 09:47:32 PDT
Comment on attachment 369080 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=369080&action=review > Source/WebCore/rendering/RenderLayer.cpp:4082 > + paintFlags.add(PaintLayerTemporaryClipRects); This disables clip caching right? Should we worry about performance?
Simon Fraser (smfr)
Comment 18 2019-05-06 10:35:02 PDT Comment hidden (obsolete)
Simon Fraser (smfr)
Comment 19 2019-05-06 22:23:04 PDT Comment hidden (obsolete)
Simon Fraser (smfr)
Comment 20 2019-05-06 22:27:10 PDT Comment hidden (obsolete)
Simon Fraser (smfr)
Comment 21 2019-05-06 22:35:40 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 22 2019-05-06 23:34:34 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 23 2019-05-06 23:34:37 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 24 2019-05-06 23:52:19 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 25 2019-05-06 23:52:23 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 26 2019-05-06 23:57:15 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 27 2019-05-06 23:57:18 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 28 2019-05-07 00:30:19 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 29 2019-05-07 00:30:25 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 30 2019-05-07 09:19:48 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 31 2019-05-07 09:19:53 PDT Comment hidden (obsolete)
Simon Fraser (smfr)
Comment 32 2019-05-07 10:57:17 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 33 2019-05-07 12:57:21 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 34 2019-05-07 12:57:24 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 35 2019-05-07 13:05:48 PDT Comment hidden (obsolete)
EWS Watchlist
Comment 36 2019-05-07 13:05:50 PDT Comment hidden (obsolete)
Simon Fraser (smfr)
Comment 37 2019-05-07 20:51:51 PDT Comment hidden (obsolete)
Simon Fraser (smfr)
Comment 38 2019-05-07 21:03:24 PDT
EWS Watchlist
Comment 39 2019-05-07 22:53:40 PDT
Comment on attachment 369357 [details] Patch Attachment 369357 [details] did not pass mac-debug-ews (mac): Output: https://webkit-queues.webkit.org/results/12130330 New failing tests: fast/hidpi/video-controls-in-hidpi.html
EWS Watchlist
Comment 40 2019-05-07 22:53:42 PDT
Created attachment 369359 [details] Archive of layout-test-results from ews112 for mac-highsierra The attached test failures were seen while running run-webkit-tests on the mac-debug-ews. Bot: ews112 Port: mac-highsierra Platform: Mac OS X 10.13.6
EWS Watchlist
Comment 41 2019-05-07 23:04:36 PDT
Comment on attachment 369357 [details] Patch Attachment 369357 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: https://webkit-queues.webkit.org/results/12130361 New failing tests: fast/scrolling/ios/overflow-scroll-overlap-4.html
EWS Watchlist
Comment 42 2019-05-07 23:04:39 PDT
Created attachment 369360 [details] Archive of layout-test-results from ews126 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews126 Port: ios-simulator-wk2 Platform: Mac OS X 10.14.4
Antti Koivisto
Comment 43 2019-05-08 00:00:56 PDT
> New failing tests: > fast/scrolling/ios/overflow-scroll-overlap-4.html This is failing because of the missing region code.
Antti Koivisto
Comment 44 2019-05-08 00:16:55 PDT
Comment on attachment 369357 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=369357&action=review Looks fine. Fixing updateEventRegion shouldn't be difficult either (same thing as paintIntoLayer) but it can be done separately if you prefer. > Source/WebCore/rendering/RenderLayer.cpp:1774 > +// ASSERT_IMPLIES(backingProvider, !isComposited()); Commented-out code. > Source/WebCore/rendering/RenderLayerBacking.cpp:679 > + if (!layerWeakPtr) { > + ASSERT_NOT_REACHED(); > + continue; > + } This seems overly defensive. We should just crash with nullptr if the logic is supposed to guarantee that these are non-null (here and elsewhere).
EWS Watchlist
Comment 45 2019-05-08 01:44:15 PDT
Comment on attachment 369357 [details] Patch Attachment 369357 [details] did not pass win-ews (win): Output: https://webkit-queues.webkit.org/results/12131207 New failing tests: http/tests/css/filters-on-iframes.html
EWS Watchlist
Comment 46 2019-05-08 01:44:22 PDT
Created attachment 369364 [details] Archive of layout-test-results from ews210 for win-future The attached test failures were seen while running run-webkit-tests on the win-ews. Bot: ews210 Port: win-future Platform: CYGWIN_NT-10.0-17763-3.0.5-338.x86_64-x86_64-64bit
Simon Fraser (smfr)
Comment 47 2019-05-08 10:24:45 PDT
Alexey Proskuryakov
Comment 48 2019-05-08 17:42:24 PDT
> webkit.org/b/197695 [ Debug ] fast/hidpi/video-controls-in-hidpi.html [ Skip ] This patch skipped an existing test. How is this OK?
Ryan Haddad
Comment 49 2019-05-08 18:20:12 PDT
Reverted r245058 for reason: Causes crashes under ASan / GuardMalloc Committed r245085: <https://trac.webkit.org/changeset/245085>
Simon Fraser (smfr)
Comment 50 2019-05-09 22:20:49 PDT
Antti Koivisto
Comment 51 2019-05-10 05:20:59 PDT
This hits debug asserts on many sites (say, nytimes.com) void RenderLayer::paintLayerContents(GraphicsContext& context, const LayerPaintingInfo& paintingInfo, OptionSet<PaintLayerFlag> paintFlags) { ASSERT(isSelfPaintingLayer() || hasSelfPaintingLayerDescendant()); (lldb) bt 10 * thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0xbbadbeef) * frame #0: 0x000000035a69285e JavaScriptCore`::WTFCrash() at Assertions.cpp:305:35 frame #1: 0x000000035ee1ce2b WebCore`WTFCrashWithInfo((null)=4368, (null)="rendering/RenderLayer.cpp", (null)="void WebCore::RenderLayer::paintLayerContents(WebCore::GraphicsContext &, const WebCore::RenderLayer::LayerPaintingInfo &, OptionSet<WebCore::RenderLayer::PaintLayerFlag>)", (null)=2340) at Assertions.h:568:5 frame #2: 0x00000003622b75f6 WebCore`WebCore::RenderLayer::paintLayerContents(this=0x00000003946d8c18, context=0x00007ffee42dc358, paintingInfo=0x00007ffee42dbde0, paintFlags=(m_storage = 96)) at RenderLayer.cpp:4368:5 frame #3: 0x00000003622d81ac WebCore`WebCore::RenderLayerBacking::paintIntoLayer(this=0x00007ffee42dbec8, layer=0x00000003946d8c18, paintFlags=(m_storage = 96))::$_9::operator()(WebCore::RenderLayer&, WTF::OptionSet<WebCore::RenderLayer::PaintLayerFlag>) const at RenderLayerBacking.cpp:2674:15 frame #4: 0x00000003622d7f70 WebCore`WebCore::RenderLayerBacking::paintIntoLayer(this=0x000000039460fa20, graphicsLayer=0x000000039473d000, context=0x00007ffee42dc358, paintDirtyRect=0x00007ffee42dc0d8, paintBehavior=(m_storage = 2048), paintingPhase='\x03') at RenderLayerBacking.cpp:2701:13 frame #5: 0x00000003622d869d WebCore`WebCore::RenderLayerBacking::paintContents(this=0x000000039460fa20, graphicsLayer=0x000000039473d000, context=0x00007ffee42dc358, paintingPhase='\x03', clip=0x00007ffee42dc160, layerPaintBehavior=2) at RenderLayerBacking.cpp:2744:9 frame #6: 0x0000000361de23b7 WebCore`WebCore::GraphicsLayer::paintGraphicsLayerContents(this=0x000000039473d000, context=0x00007ffee42dc358, clip=0x00000003947f49b8, layerPaintBehavior=2) at GraphicsLayer.cpp:501:14 frame #7: 0x0000000361e5a8ad WebCore`WebCore::GraphicsLayerCA::platformCALayerPaintContents(this=0x000000039473d000, (null)=0x0000000392633000, context=0x00007ffee42dc358, clip=0x00000003947f49b8, layerPaintBehavior=2) at GraphicsLayerCA.cpp:1678:5 frame #8: 0x000000035f4df4c3 WebCore`WebCore::PlatformCALayer::drawLayerContents(context=0x00007fc3dced2ba0, platformCALayer=0x0000000392633000, dirtyRects=0x00000003947f49a8, layerPaintBehavior=2) at PlatformCALayerCocoa.mm:1198:28 frame #9: 0x000000010c5056f0 WebKit`WebKit::RemoteLayerBackingStore::drawInContext(this=0x00000003947f4958, context=0x000000039ff97840, backImage=0x0000000000000000) at RemoteLayerBackingStore.mm:355:9
Simon Fraser (smfr)
Comment 52 2019-05-10 08:52:22 PDT
Filed bug 197776 on that.
Michael Catanzaro
Comment 53 2019-05-10 10:06:57 PDT
[885/2246] Building CXX object Source/WebCore/CMakeFiles/...es/WebCore/unified-sources/UnifiedSource-043dd90b-8.cpp.o In file included from DerivedSources/WebCore/unified-sources/UnifiedSource-043dd90b-8.cpp:5: ../../Source/WebCore/rendering/RenderLayer.cpp: In member function ‘WTF::Ref<WebCore::ClipRects> WebCore::RenderLayer::updateClipRects(const WebCore::RenderLayer::ClipRectsContext&)’: ../../Source/WebCore/rendering/RenderLayer.cpp:5503:15: warning: unused variable ‘parentLayer’ [-Wunused-variable] 5503 | if (auto* parentLayer = (clipRectsContext.rootLayer != this ? parent() : nullptr)) | ^~~~~~~~~~~ This condition here: RefPtr<ClipRects> parentClipRects; // For transformed layers, the root layer was shifted to be us, so there is no need to // examine the parent. We want to cache clip rects with us as the root. if (auto* parentLayer = (clipRectsContext.rootLayer != this ? parent() : nullptr)) parentClipRects = this->parentClipRects(clipRectsContext); Should now be simplified to: RefPtr<ClipRects> parentClipRects; // For transformed layers, the root layer was shifted to be us, so there is no need to // examine the parent. We want to cache clip rects with us as the root. if (clipRectsContext.rootLayer != this) parentClipRects = this->parentClipRects(clipRectsContext);
Michael Catanzaro
Comment 54 2019-05-10 10:09:41 PDT
Er no, that's a disaster think-o, sorry. Should be simplified to: if (clipRectsContext.rootLayer != this && parent())
Michael Catanzaro
Comment 55 2019-05-10 10:25:45 PDT
Will fix in: bug #197785. (Assuming the new logic is correct and only needs to be simplified.)
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