> [JDK-8240696](https://bugs.openjdk.org/browse/JDK-8240696) added the native > method for `Reference.clear`. The original patch skipped intrinsification of > this method, because we thought `Reference.clear` is not on a performance > sensitive path. However, it shows up prominently on simple benchmarks that > touch e.g. `ThreadLocal` cleanups. See the bug for an example profile with > `RRWL` benchmarks. > > We need to know the actual oop strongness/weakness before we call into C2 > Access API, this work models this after existing code for `refersTo0` > intrinsics. C2 Access also need a support for `AS_NO_KEEPALIVE` for stores. > > Additional testing: > - [x] Linux x86_64 server fastdebug, `all` > - [x] Linux AArch64 server fastdebug, `all`
Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 18 commits: - Simplify: just do keep alive checks - Merge branch 'master' into JDK-8329597-intrinsify-reference-clear - More precise bit-unmasks - Reconcile with late barrier expansion in G1 - Merge branch 'master' into JDK-8329597-intrinsify-reference-clear - Review comments - Merge branch 'master' into JDK-8329597-intrinsify-reference-clear - Also dispatch to slow-path on other arches - Fix other arches - Tighten up comments in Reference javadoc - ... and 8 more: https://git.openjdk.org/jdk/compare/580eb62d...9f7ad7ab ------------- Changes: https://git.openjdk.org/jdk/pull/20139/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20139&range=08 Stats: 361 lines in 25 files changed: 340 ins; 0 del; 21 mod Patch: https://git.openjdk.org/jdk/pull/20139.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/20139/head:pull/20139 PR: https://git.openjdk.org/jdk/pull/20139
