Bug 31473 – Allow custom memory allocation control for 10 classes of the platform directory in WebCore

• Component: WebCore Misc.
• Status: RESOLVED FIXED

[Zoltan Horvath]

Inherits the following classes from FastAllocBase because these are instantiated by 'new':

class  AnimationList         - instantiated at WebCore/rendering/style/StyleRareNonInheritedData.cpp:85
class  Color                 - instantiated at WebCore/rendering/RenderTheme.cpp:48
struct Length                - instantiated at WebCore/platform/Length.cpp:103
class  PlatformKeyboardEvent - instantiated at WebCore/dom/KeyboardEvent.cpp:63
class  ContextMenuItem       - instantiated at WebCore/platform/ContextMenu.cpp:70
class  DeprecatedPtrList     - instantiated at WebCore/rendering/RenderBlock.cpp:2284

Inherits the following classes from Noncopyable because these are instantiated by 'new' and no need to be copyable:

class  GraphicsContextPrivate - instantiated at WebCore/platform/graphics/GraphicsContext.cpp:78
class  FontCache              - instantiated at WebCore/platform/graphics/qt/FontCacheQt.cpp:43
struct MediaPlayerFactory     - instantiated at WebCore/platform/graphics/MediaPlayer.cpp:163

[Zoltan Horvath]

Created attachment 43155 [details]
proposed patch

[Zoltan Horvath]

Created attachment 43156 [details]
proposed patch

[Darin Adler]

Comment on attachment 43156 [details]
proposed patch

> -    class ContextMenuItem {
> +    class ContextMenuItem : public FastAllocBase {

Should be Noncopyable instead.

> -    class PlatformKeyboardEvent {
> +    class PlatformKeyboardEvent : public FastAllocBase {

I think this should be Noncopyable instead. Needs testing to be sure.

review- because we'd like keep direct FastAllocBase use to a minimum and use Noncopyable whenever appropriate.

[Zoltan Horvath]

(In reply to comment #3)
> (From update of attachment 43156 [details])
> > -    class ContextMenuItem {
> > +    class ContextMenuItem : public FastAllocBase {
> 
> Should be Noncopyable instead.

It can't be Noncopyable because WebCore/platform/qt/ContextMenuQt.cpp:51 m_items.append(item); copies a ContextMenuItem instance.


> > -    class PlatformKeyboardEvent {
> > +    class PlatformKeyboardEvent : public FastAllocBase {
> 
> I think this should be Noncopyable instead. Needs testing to be sure.
> 
> review- because we'd like keep direct FastAllocBase use to a minimum and use
> Noncopyable whenever appropriate.

The PlatformKeyboardEvent's problem comes from WebCore/dom/KeyboardEvent.cpp:63 it would use its copy constructor.

[Zoltan Horvath]

Btw, I analyzed all classes in the patch, and if a class is inherited from FastAllocBase than it won't compile with Noncopyable some reason.

[Zoltan Horvath]

Comment on attachment 43156 [details]
proposed patch

I mark it to r? again.

[Zoltan Horvath]

Landed in 51149.
http://trac.webkit.org/changeset/51149