On Wed, 17 Dec 2025 10:21:24 GMT, Stefan Karlsson <[email protected]> wrote:
> Sub-classes of `InstanceKlass` can't have C++ fields because they would end > up overlayed on top of the vtable and other dynamically sized sections of the > `InstanceKlass` object. > > To handle that the `InlineKlass` has a companion class named > `InlineKlassFixedBlock`, which lists all the member fields that belongs to > the InlineKlass, and an instance of that gets stamped into the `InlineKlass` > object after the parts that are provided by the `InstanceKlass`. > > I propose a few changes: > > 1) Move `InlineKlassFixedBlock` away from instanceKlass.hpp and place it > inside inlineKlass.hpp instead. > > 2) Nest `InlineKlassFixedBlock` it inside `InlineKlass`. It's only > `InlineKlass `(and the compilers) that touch these fields, so it doesn't have > to be a public, top-level class. > > 3) Rename it from `InlineKlassFixedBlock` to `InlineKlass::Members`. I think > that "fixed block" term is unclear and doesn't help the reader understand its > role in the `InlineKlass`. Hopefully, the name `Members` is a clearer. > > WDYT? This pull request has now been integrated. Changeset: d586e57d Author: Stefan Karlsson <[email protected]> Committer: Frederic Parain <[email protected]> URL: https://git.openjdk.org/valhalla/commit/d586e57d7488461e808e7cb566586d7112b72dc6 Stats: 222 lines in 15 files changed: 98 ins; 53 del; 71 mod 8373864: [lworld] Hide and rename InstanceKlassFixedBlock Reviewed-by: phubner, fparain ------------- PR: https://git.openjdk.org/valhalla/pull/1812
