Bug 190261 – RenderLayer should traverse the render tree only once to draw its contents

• Component: Layout and Rendering
• Status: NEW

[Said Abou-Hallawa]

To draw a RenderLayer, WebKit has to follow the CSS stacking context order to paint different phases from the render tree. This patch tries to consolidate the render tree traversal in one pass using DisplayLists. The render tree objects can push their drawing into different DisplayLists in the same call. The purpose of this change is to accelerate the render layer drawing.

Having the drawing recorded in DisplayLists should provide many optimization opportunities.
1. Caching the DisplayLists for later reuse.
2. Delete no-op drawing operations, for example { context.save(); context.restore(); } or { context.save(); context.clip(); context.restore(); }
3. Generating the DisplayList can happen in parallel.

[Said Abou-Hallawa]

Created attachment 351550 [details]
Patch

[Said Abou-Hallawa]

Created attachment 351551 [details]
Patch for review

[Said Abou-Hallawa]

Created attachment 351567 [details]
Patch

[EWS Watchlist]

Comment on attachment 351567 [details]
Patch

Attachment 351567 [details] did not pass mac-ews (mac):
Output: https://webkit-queues.webkit.org/results/9448749

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351570 [details]
Archive of layout-test-results from ews103 for mac-sierra

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: ews103  Port: mac-sierra  Platform: Mac OS X 10.12.6

[EWS Watchlist]

Comment on attachment 351567 [details]
Patch

Attachment 351567 [details] did not pass mac-wk2-ews (mac-wk2):
Output: https://webkit-queues.webkit.org/results/9448831

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351573 [details]
Archive of layout-test-results from ews107 for mac-sierra-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews107  Port: mac-sierra-wk2  Platform: Mac OS X 10.12.6

[EWS Watchlist]

Comment on attachment 351567 [details]
Patch

Attachment 351567 [details] did not pass mac-debug-ews (mac):
Output: https://webkit-queues.webkit.org/results/9448838

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351574 [details]
Archive of layout-test-results from ews115 for mac-sierra

The attached test failures were seen while running run-webkit-tests on the mac-debug-ews.
Bot: ews115  Port: mac-sierra  Platform: Mac OS X 10.12.6

[Said Abou-Hallawa]

Created attachment 351617 [details]
Patch

[Said Abou-Hallawa]

Created attachment 351620 [details]
Patch for review

[EWS Watchlist]

Comment on attachment 351617 [details]
Patch

Attachment 351617 [details] did not pass mac-ews (mac):
Output: https://webkit-queues.webkit.org/results/9455160

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351629 [details]
Archive of layout-test-results from ews100 for mac-sierra

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: ews100  Port: mac-sierra  Platform: Mac OS X 10.12.6

[EWS Watchlist]

Comment on attachment 351617 [details]
Patch

Attachment 351617 [details] did not pass mac-wk2-ews (mac-wk2):
Output: https://webkit-queues.webkit.org/results/9455294

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351632 [details]
Archive of layout-test-results from ews104 for mac-sierra-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews104  Port: mac-sierra-wk2  Platform: Mac OS X 10.12.6

[EWS Watchlist]

Comment on attachment 351617 [details]
Patch

Attachment 351617 [details] did not pass mac-debug-ews (mac):
Output: https://webkit-queues.webkit.org/results/9455265

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351634 [details]
Archive of layout-test-results from ews115 for mac-sierra

The attached test failures were seen while running run-webkit-tests on the mac-debug-ews.
Bot: ews115  Port: mac-sierra  Platform: Mac OS X 10.12.6

[EWS Watchlist]

Comment on attachment 351617 [details]
Patch

Attachment 351617 [details] did not pass ios-sim-ews (ios-simulator-wk2):
Output: https://webkit-queues.webkit.org/results/9455992

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351638 [details]
Archive of layout-test-results from ews122 for ios-simulator-wk2

The attached test failures were seen while running run-webkit-tests on the ios-sim-ews.
Bot: ews122  Port: ios-simulator-wk2  Platform: Mac OS X 10.13.6

[EWS Watchlist]

Comment on attachment 351617 [details]
Patch

Attachment 351617 [details] did not pass ios-sim-ews (ios-simulator-wk2):
Output: https://webkit-queues.webkit.org/results/9456992

Number of test failures exceeded the failure limit.

[EWS Watchlist]

Created attachment 351645 [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 10.13.6