On Tue, 24 Mar 2026 15:30:13 GMT, Stefan Karlsson <[email protected]> wrote:
> In preparation for JEP-401 I propose that we remove the unused larval bit > from the markWord. The last API to use it was removed with > [JDK-8373375](https://bugs.openjdk.org/browse/JDK-8373375). > > I received feedback that we should still keep the mark word bit reserved for > Project Valhalla, so that's reflected in the change. > > There is still a lot of JIT compiler support for larval bits, but I've > limited this PR to only clean up the markWord usages. > > It would be good to get some feedback about what to do with the callnode.cpp > change. > > Tested locally with `test TEST=hotspot_valhalla`. src/hotspot/share/prims/unsafe.cpp line 258: > 256: void put(T x) { > 257: GuardUnsafeAccess guard(_thread); > 258: assert(_obj == nullptr || !_obj->is_inline_type(), "must be an > object instance"); The message of the assert seems to date from the ancient times when value types were not subclasses of j.l.Object. A more accurate message today would be "must be an object with identity". This applies to the assert at line 312 too. ------------- PR Review Comment: https://git.openjdk.org/valhalla/pull/2258#discussion_r2982762174
