1473136 - NeedsActiveLayer is frequently checked when it could be cached

Status: RESOLVED FIXED

(Core :: Web Painting, enhancement)

Description

[Bas Schouten (:bas.schouten)]

NeedsActiveLayer does not mutate without a new DisplayItem being created. This means we only need to run it once for nsDisplayOpacity rather than calling it multiple times. This makes for a big performance improvement.

Comment 1

[Bas Schouten (:bas.schouten)]

Attachment: Bug 1473136: Cache mNeedsActiveLayer once for nsDisplayOpacity.

Review commit: https://reviewboard.mozilla.org/r/254570/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/254570/

Comment 2

[Matt Woodrow (:mattwoodrow)]

Comment on attachment 8989546 [details]
Bug 1473136: Cache mNeedsActiveLayer once for nsDisplayOpacity.

https://reviewboard.mozilla.org/r/254570/#review261414

::: layout/generic/nsFrame.cpp:2956
(Diff revision 1)
>        nsSVGIntegrationUtils::GetRequiredSourceForInvalidArea(this, visibleRect);
>      aBuilder->EnterSVGEffectsContents(&hoistedScrollInfoItemsStorage);
>    }
>  
> +
> +  bool needsActiveLayer = false;

Probably worth calling this needsActiveOpacityLayer, too many layers things going on in this function.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/bf97c22331fa
Cache mNeedsActiveLayer once for nsDisplayOpacity. r=mattwoodrow

Comment 4

[Raul Gurzau (:RaulG)]

https://hg.mozilla.org/mozilla-central/rev/bf97c22331fa