I think we don't need to addref/release so much if containers aren't changing.

Comment on attachment 8905952 [details] [diff] [review] dosetrange.diff Review of attachment 8905952 [details] [diff] [review]: ----------------------------------------------------------------- ::: dom/base/nsRange.h @@ +598,5 @@ > > template<typename A, typename B> > RangeBoundaryBase& operator=(const RangeBoundaryBase<A,B>& aOther) > { > + if (mParent != aOther.mParent) { Please, write a comment saying why this is needed.

Pushed by opettay@mozilla.com: https://hg.mozilla.org/integration/mozilla-inbound/rev/d8ce26333a8b Try to Release/AddRef a bit less in nsRange::DoSetRange, r=baku

Is is possible that we should just be using move assignment in the hot places this gets called, instead of copy assignment?

How would that help? And note, this is a case where a raw pointer is assigned to a nsCOMPtr

Oh, I see. Templated copy assignment, bleh. You're right, it wouldn't do anything for raw assignment to nsCOMPtr. But in the nsCOMPtr assignment case, move assignment (or even writing out the actual copy assignment operator to handle that case, since the templated one won't be called in that case) would be beneficial.