Bug: CTW fails compiling java/util/Base64$Encode

[Aleksey Shipilev]

Roland, can you take a look?

Seems to be reliably reproducible in 2 minutes with current jdk/jdk:

CONF=linux-x86_64-server-fastdebug make run-test TEST=applications/ctw/modules/
TEST_VM_OPTS="-XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:-TieredCompilation
-XX:+UnlockDiagnosticVMOptions -XX:+ShenandoahVerifyOptoBarriers"

TEST RESULT: Failed. Execution failed: `main' threw exception: java.lang.AssertionError: There were
1 errors:[{modules_java_base_0: failed during compilation of class #2144 : java/util/Base64$Encoder}]

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  Internal Error
(/home/shade/trunks/jdk-jdk/src/hotspot/share/gc/shenandoah/c2/shenandoahSupport.cpp:1084),
pid=18408, tid=18430
#  fatal error: encodeBlock not covered
#
# JRE version: OpenJDK Runtime Environment (13.0) (fastdebug build 13-internal+0-adhoc.shade.jdk-jdk)
# Java VM: OpenJDK 64-Bit Server VM (fastdebug 13-internal+0-adhoc.shade.jdk-jdk, mixed mode,
sharing, compressed oops, shenandoah gc, linux-amd64)
# Problematic frame:
# V  [libjvm.so+0x1794518]  ShenandoahBarrierNode::verify(RootNode*)+0x1428


-Aleksey