hg: jdk/sandbox: 8244721: CTW: C2 (Shenandoah) compilation fails with "unexpected infinite loop graph shape"

[chris.hegarty at oracle.com]

Changeset: 37ab496acb09
Author:    roland
Date:      2020-05-15 10:24 +0200
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/37ab496acb09

8244721: CTW: C2 (Shenandoah) compilation fails with "unexpected infinite loop graph shape"
Reviewed-by: shade

! src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp
! test/hotspot/jtreg/gc/shenandoah/compiler/BarrierInInfiniteLoop.java