The style candidate cache had regressed a few times (see #12534), and my
intuition is that being able to disable all style sharing with a single rule in
the page is really unfortunate.
This commit redesigns the style sharing cache in order to be a optimistic cache,
but then reject candidates if they match different sibling-affecting selectors
in the page, for example.
So far the numbers have improved, but not so much as I'd wanted (~10%/20% of
non-incremental restyling time in general). The current implementation is really
dumb though (we recompute and re-match a lot of stuff), so we should be able to
optimise it quite a bit.
I have different ideas for improving it (that may or may not work), apart of the
low-hanging fruit like don't re-matching candidates all the time but I have to
measure the real impact.
Also, I need to verify it against try.
This is a rewrite for how style interfaces with its consumers in order to allow
different representations for an element snapshot.
This also changes the requirements of an element snapshot, requiring them to
only implement MatchAttr, instead of MatchAttrGeneric. This is important for
stylo since implementing MatchAttrGeneric is way more difficult for us given the
atom limitations. This also allows for more performant implementations in the
Gecko side of things.
These can't be supported in Servo as of right now, because I'm not
totally sure the accesses that should be done in layout would be
thread-safe.
It can be revisited later though.
In rust-url 1.0 the `Url` struct is going to have private fields, and there
is no way to to create an aribitrary one without going through the parser.
The plugin never had a clear demonstrated performance benefit,
it was made mostly because it was possible and relatively easy at the time.
Don't re-add stylesheets to recompute vw/vh lengths
This is a follow-up to #9876. It avoids clearing and rebuilding SelectorMaps
when vh and vw units need to be recomputed. Instead it just dirties all nodes,
to force elements to be re-cascaded.
Filed #10104 for later follow-up work to dirty only affected nodes.
r? @SimonSapin
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This is a follow-up to #9876. It avoids clearing and rebuilding SelectorMaps
when vh and vw units need to be recomputed. Instead it just dirties all nodes,
to force elements to be re-cascaded.
Filed #10104 for later follow-up work to dirty only affected nodes.
Details ui
Requires a patch to rust-selectors, and doesn't currently recalculate the styles correctly (which is needed to make actual toggling work correctly).
Still trying to figure out what it takes to get style recalc to do what this needs.
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