hg: shenandoah/jdk11: [backport] 8216989: CardTableBarrierSetAssembler::gen_write_ref_array_post_barrier() does not check for zero length on AARCH64

[shade at redhat.com]

Changeset: 42686e3ea552
Author:    shade
Date:      2019-09-04 10:34 +0200
URL:       https://hg.openjdk.java.net/shenandoah/jdk11/rev/42686e3ea552

[backport] 8216989: CardTableBarrierSetAssembler::gen_write_ref_array_post_barrier() does not check for zero length on AARCH64

! src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetAssembler_aarch64.cpp
! src/hotspot/cpu/aarch64/gc/shenandoah/shenandoahBarrierSetAssembler_aarch64.hpp