Bug 185752 – Lazily create WebCore::Timer for WebCore::Image

• Status: RESOLVED
• Resolution: FIXED
• Component: WebCore Misc.

[David Kilzer (:ddkilzer)]

Not every image is an animated image, so lazily creating m_animationStartTimer saves 56 bytes per instance of WebCore::Image.

[David Kilzer (:ddkilzer)]

Created attachment 340663 [details]
Patch v1

[Radar WebKit Bug Importer]

<rdar://problem/40348570>

[David Kilzer (:ddkilzer)]

This bug improves the safety of using WebCore::Image in the UI Process since current uses do not include animated images.

It also prevents a WebCore::Timer from being allocated for a nullImage.

[Simon Fraser (smfr)]

Comment on attachment 340663 [details]
Patch v1

View in context: https://bugs.webkit.org/attachment.cgi?id=340663&action=review

> Source/WebCore/platform/graphics/Image.cpp:351
> +    std::call_once(onceFlag, [this] {

Don't need call_once. Just if (!m_animationStartTimer)

> Source/WebCore/platform/graphics/Image.h:203
> +    std::once_flag onceFlag;

Don't need this here.

[David Kilzer (:ddkilzer)]

Comment on attachment 340663 [details]
Patch v1

View in context: https://bugs.webkit.org/attachment.cgi?id=340663&action=review

>> Source/WebCore/platform/graphics/Image.cpp:351
>> +    std::call_once(onceFlag, [this] {
> 
> Don't need call_once. Just if (!m_animationStartTimer)

So we can assume Image::startAnimationAsynchronously() and Image::animationPending() are always called on the main thread?

>> Source/WebCore/platform/graphics/Image.h:203
>> +    std::once_flag onceFlag;
> 
> Don't need this here.

Saves another 8 bytes.  WebCore::Image goes down from 104 bytes to just 40 bytes with this change.

[David Kilzer (:ddkilzer)]

Committed r231940: <https://trac.webkit.org/changeset/231940>