On Wed, 25 May 2022 09:38:08 GMT, Claes Redestad <redes...@openjdk.org> wrote:
> The bespoke caching scheme in `jl.invoke.LambdaFormEditor.TransformKey` > allows keys to be compacted when all byte values of the key fit in 4 bits, > otherwise a byte array is allocated and used. This means that all transforms > with a kind value above 15 will be forced to allocate and use array > comparisons. > > Removing unused and folding some transforms to ensure all existing kinds can > fit snugly within the 0-15 value range realize a minor improvement to > footprint, speed and allocation pressure of affected transforms, e.g. > ~300bytes/op reduction in the `StringConcatFactoryBootstraps` microbenchmark: > > Baseline: > > Benchmark Mode Cnt > Score Error Units > SCFB.makeConcatWithConstants avgt 15 > 2048.475 ? 69.887 ns/op > SCFB.makeConcatWithConstants:?gc.alloc.rate.norm avgt 15 > 3487.311 ? 80.385 B/op > > > Patched: > > Benchmark Mode Cnt > Score Error Units > SCFB.makeConcatWithConstants avgt 15 > 1961.985 ? 101.519 ns/op > SCFB.makeConcatWithConstants:?gc.alloc.rate.norm avgt 15 > 3156.478 ? 183.600 B/op This pull request has now been integrated. Changeset: be933185 Author: Claes Redestad <redes...@openjdk.org> URL: https://git.openjdk.java.net/jdk/commit/be93318576896e8f5f9733ae1f7e3e74d63f5594 Stats: 124 lines in 2 files changed: 70 ins; 21 del; 33 mod 8287292: Improve TransformKey to pack more kinds of transforms efficiently Reviewed-by: jlaskey, jvernee, mchung ------------- PR: https://git.openjdk.java.net/jdk/pull/8881