RFR: 8261251: Shenandoah: Use object size for full GC humongous compaction

[Andrew Haley]

On Fri, 5 Feb 2021 18:21:55 GMT, Roman Kennke <rkennke at openjdk.org> wrote:

> Currently, copying objects in full GC humongous object comaction copies the full region. We can limit that to copying only the object size and save some wasted cycles. Also, this fixes a test failure with loom where object copy checks that the given size matches the object size.
> 
>  - [x] hotspot_gc_shenandoah
>  - [x] tier1(+Shenandoah)

Marked as reviewed by aph (Reviewer).

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

PR: https://git.openjdk.java.net/jdk/pull/2433