Bug 158045 – REGRESSION: JSBench spends a lot of time transitioning to/from dictionary

• Status: RESOLVED
• Resolution: FIXED
• Component: New Bugs

[Geoffrey Garen]

REGRESSION: JSBench spends a lot of time transitioning to/from dictionary

[Geoffrey Garen]

Created attachment 279719 [details]
Patch

[Saam Barati]

Comment on attachment 279719 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=279719&action=review

r=me

> Source/JavaScriptCore/runtime/Operations.h:212
> +            if (structure->hasBeenFlattenedBefore())
> +                return InvalidPrototypeChain;

Is it worth having an assertion in flattenDictionaryStructure to make sure we don't end up in a cycle of flattening?

[Geoffrey Garen]

> Is it worth having an assertion in flattenDictionaryStructure to make sure
> we don't end up in a cycle of flattening?

I'm not sure. Right now, flattening is a policy decision, and some callers choose to flatten even if in a cycle.

We could add the assertion, but only after changing the policy. It's not clear to me if a policy change is warranted or not.

[Build Bot]

Comment on attachment 279719 [details]
Patch

Attachment 279719 [details] did not pass mac-wk2-ews (mac-wk2):
Output: http://webkit-queues.webkit.org/results/1377260

New failing tests:
js/cached-window-properties.html

[Build Bot]

Created attachment 279726 [details]
Archive of layout-test-results from ews105 for mac-yosemite-wk2

The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: ews105  Port: mac-yosemite-wk2  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 279719 [details]
Patch

Attachment 279719 [details] did not pass mac-ews (mac):
Output: http://webkit-queues.webkit.org/results/1377274

New failing tests:
js/cached-window-properties.html

[Build Bot]

Created attachment 279727 [details]
Archive of layout-test-results from ews101 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: ews101  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Build Bot]

Comment on attachment 279719 [details]
Patch

Attachment 279719 [details] did not pass ios-sim-ews (ios-simulator-wk2):
Output: http://webkit-queues.webkit.org/results/1377277

New failing tests:
js/cached-window-properties.html

[Build Bot]

Created attachment 279729 [details]
Archive of layout-test-results from ews124 for ios-simulator-wk2

The attached test failures were seen while running run-webkit-tests on the ios-sim-ews.
Bot: ews124  Port: ios-simulator-wk2  Platform: Mac OS X 10.11.4

[Build Bot]

Comment on attachment 279719 [details]
Patch

Attachment 279719 [details] did not pass mac-debug-ews (mac):
Output: http://webkit-queues.webkit.org/results/1377291

New failing tests:
js/cached-window-properties.html

[Build Bot]

Created attachment 279731 [details]
Archive of layout-test-results from ews116 for mac-yosemite

The attached test failures were seen while running run-webkit-tests on the mac-debug-ews.
Bot: ews116  Port: mac-yosemite  Platform: Mac OS X 10.10.5

[Geoffrey Garen]

Committed r201436: <http://trac.webkit.org/changeset/201436>

[Saam Barati]

(In reply to comment #12)
> Committed r201436: <http://trac.webkit.org/changeset/201436>

Looks like this might also be a 9% code-load speedup
https://arewefastyet.com/#machine=29&view=breakdown&suite=octane

[Ryosuke Niwa]

This patch appears to have caused 30% regression on Dromaeo DOM core.

[WebKit Commit Bot]

Re-opened since this is blocked by bug 158143

[Geoffrey Garen]

Committed r201573: <http://trac.webkit.org/changeset/201573>

[Ryosuke Niwa]

This was 3% overall JSBench progression.