We have about 11,500 of these when loading gmail in a Stylo-enabled build, from
SpecifiedUrls; the objects themselves account for about 1.3 MiB of memory, and
the strings within them about 2.9 MiB.
We also have a very small number of them on the Gecko side.
Share specified URLs with Gecko
This makes use of our Arc offset machinery to allow Gecko to store Arc<String> values and ensure there are used appropriately.
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix [bug 1397971](https://bugzilla.mozilla.org/show_bug.cgi?id=1397971).
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This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/18516)
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We have about 11,500 of these when loading gmail in a Stylo-enabled build, from
SpecifiedUrls; the objects themselves account for about 1.3 MiB of memory, and
the strings within them about 2.9 MiB.
We also have a very small number of them on the Gecko side.
This patch replaces the handwritten MallocSizeOf implementation for
PropertyDeclaration with a derived one, which gives much more thorough
measurement.
This requires (a) deriving MallocSizeOf for a *lot* of additional types (most
of which already have `derive(HeapSizeOf)` in Servo builds), and (b)
implementing MallocSizeOf for a few more types in the `malloc_size_of` crate.
These changes would significantly improve the reporting coverage for gmail if
it weren't for the fact that SpecifiedUrl isn't measured due to a lack of
clarity about its fields; that can be fixed as a follow-up once bug 1397971 has
landed.
The alias is left there temporarilly and will be removed completely in a later commit where
also components/style/gecko/generated/structs_{debug|release}.rs are re-generated (they still
use the old alias).
We will need to convert from URLValueData to SpecifiedUrl when cloning the
stylo's data from gecko's data. Because the filter structure on gecko has url as
URLValue type. We will use this convert function when interpolating as
discrete also(Bug 1368610).
It's a bit unfortunate the use separate implementations of SpecifiedUrl for Servo
and Gecko, but they're different enough at this point that I don't think it really
makes sense to try to share everything. Splitting them out has some nice
simplifications as well.
I recognize that there's still some potential correctness issues for Servo using
the resolved URI in various places where the original URI may be the right thing,
but I've got too much on my plate to look into that for now.
MozReview-Commit-ID: BeDu93TQ4Ow
