On Wed, 2 Sep 2026 15:05:48 GMT, Fredrik Bredberg <[email protected]> wrote:
>> Since [JDK-8389325](https://bugs.openjdk.org/browse/JDK-8389325) >> `ObjectMonitor::_metadata` only contains a copy of the object’s hash code. >> But: >> >> 1. A `ObjectMonitorTable` lookup get the hash directly from the object’s >> mark word, and ... >> 2. ... no synchronization code uses the copy stored in the monitor. >> >> Therefore this PR removes the redundant `_metadata` field and its related >> metadata/hash accessors, diagnostics, and serviceability support. >> >> Passes tier1-5 tests successfully on supported platforms. >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > Fredrik Bredberg has updated the pull request incrementally with one > additional commit since the last revision: > > Updated after review lgtm. This should not clash with [JDK-8391174](https://bugs.openjdk.org/browse/JDK-8391174), but I'd merge checked regardless. Also given the `JDK-8391174` I would probably have changed all the markWord hash zero checks and asserts to be `[!]obj->has_identity_hash()` checks / asserts as it reflects the object invariants better. ------------- Marked as reviewed by aboldtch (Reviewer). PR Review: https://git.openjdk.org/jdk/pull/32573#pullrequestreview-5099140718
