There are about 362K Vector<AtomicStringImpl*> backing stores getting allocated and freed on a run of PLUM, in the RuleFeatures::classesMatchingAncestors vector.
Since RuleFeatures is only ever stack-allocated, we can avoid most/all of this by giving it some inline capacity.
Created attachment 280463 [details]
Comment on attachment 280463 [details]
Clearing flags on attachment: 280463
Committed r201697: <http://trac.webkit.org/changeset/201697>
All reviewed patches have been landed. Closing bug.