RFR: 8312321: GenShen: Remembered set scan may encounter garbage objects

[Kelvin Nilsen]

On Tue, 18 Jul 2023 21:56:20 GMT, William Kemper <wkemper at openjdk.org> wrote:

> During a global cycle, regions with no live objects may be reclaimed early (before evacuation). Once this happens, we _must_ coalesce and fill any dead objects in old regions because they may hold pointers into the reclaimed regions (even if the gc is cancelled before coalesce and fill). A subsequent scan of the remembered set may crash if it encounters these objects.

Marked as reviewed by kdnilsen (Committer).

-------------

PR Review: https://git.openjdk.org/shenandoah/pull/297#pullrequestreview-1538344536