Bug 54360 – Enable fast path selector checking for child and subselector combinators

• Component: CSS
• Status: RESOLVED FIXED

[Antti Koivisto]

Currently the fast path(CSSStyleSelector::SelectorChecker::fastCheckSelector) is enabled for descendant combinators only. It should be enabled for child and subselector combinators too.

[Antti Koivisto]

Created attachment 82269 [details]
patch

[Darin Adler]

Comment on attachment 82269 [details]
patch

View in context: https://bugs.webkit.org/attachment.cgi?id=82269&action=review

Are enough of these cases covered by existing tests?

> Source/WebCore/css/CSSStyleSelector.cpp:2146
> +template <class SelectorChecker>
> +inline bool fastCheckSingleSelector(const CSSSelector*& selector, const Element*& element, const CSSSelector*& topChildOrSubselector, const Element*& topChildOrSubselectorMatchElement)

We can pass functions as template arguments. Wrapping each function in a class is unnecessary.

    template<bool selectorChecker(const Element*, AtomicStringImpl*)>

> Source/WebCore/css/CSSStyleSelector.cpp:2149
> +    while (element) {

I think this would read slightly better as a for loop.

> Source/WebCore/css/CSSStyleSelector.cpp:2157
> +            };

Excess semicolon here.

[Antti Koivisto]

(In reply to comment #2)
> (From update of attachment 82269 [details])
> View in context: https://bugs.webkit.org/attachment.cgi?id=82269&action=review
> 
> Are enough of these cases covered by existing tests?

I think we have decent coverage, based on the tests I broke at different points.

> We can pass functions as template arguments. Wrapping each function in a class is unnecessary.

Very true, will fix.

[Antti Koivisto]

http://trac.webkit.org/changeset/78556