On Thu, 30 Mar 2023 12:49:39 GMT, John Hendrikx <jhendr...@openjdk.org> wrote:
> This fix introduces immutable sets of `PseudoClass` almost everywhere, as > they are rarely modified. These are re-used by caching them in a new class > `ImmutablePseudoClassSetsCache`. > > In order to make this work, `BitSet` had to be cleaned up. It made > assumptions about the collections it is given (which may no longer always be > another `BitSet`). I also added the appropriate null checks to ensure there > weren't any other bugs lurking. > > Then there was a severe bug in `toArray` in both the subclasses that > implement `BitSet`. > > The bug in `toArray` was incorrect use of the variable `index` which was used > for both advancing the pointer in the array to be generated, as well as for > the index to the correct `long` in the `BitSet`. This must have resulted in > other hard to reproduce problems when dealing with `Set<PseudoClass>` or > `Set<StyleClass>` if directly or indirectly calling `toArray` (which is for > example used by `List.of` and `Set.of`) -- I fixed this bug because I need to > call `Set.copyOf` which uses `toArray` -- as the same bug was also present in > `StyleClassSet`, I fixed it there as well. > > The net result of this change is that there are far fewer `PseudoClassState` > objects created; the majority of these are never modified, and the few that > are left are where you'd expect to see them modified. > > A test with 160 nested HBoxes which were given the hover state shows a 99.99% > reduction in `PseudoClassState` instances and a 70% reduction in heap use > (220 MB -> 68 MB), see the linked ticket for more details. > > Although the test case above was extreme, this change should have positive > effects for most applications. This pull request has now been integrated. Changeset: 5e145cc0 Author: John Hendrikx <jhendr...@openjdk.org> URL: https://git.openjdk.org/jfx/commit/5e145cc06ef68c50a4ffc95574fdafd44e054100 Stats: 326 lines in 10 files changed: 195 ins; 90 del; 41 mod 8199216: Quadratic layout time with nested nodes and pseudo-class in style sheet Reviewed-by: angorya, jvos, mstrauss, kcr, mhanl ------------- PR: https://git.openjdk.org/jfx/pull/1076
