CI: add workaround for Java 16

tools/ci/bench-base.sh

@@ -6,5 +6,5 @@ java -jar "$RENAISSANCE_JAR" --raw-list > list.txt
 
 for BENCH in $(cat list.txt); do
 	echo "====> $BENCH"
-	java -Xms2500M -Xmx2500M -jar "$RENAISSANCE_JAR" -c test -r 1 --csv output.csv --json output.json "$BENCH" || exit 1
+	java -Xms2500M -Xmx2500M $( get_jvm_workaround_args ) -jar "$RENAISSANCE_JAR" -c test -r 1 --csv output.csv --json output.json "$BENCH" || exit 1
 done

tools/ci/bench-jmh.sh

@@ -6,6 +6,7 @@ source "$(dirname "$0")/common.sh"
 
 java -jar "$RENAISSANCE_JMH_JAR" \
 	-jvmArgs -Xms2500M -jvmArgs -Xmx2500m \
+	$( for arg in $( get_jvm_workaround_args ); do echo "-jvmArgs" "$arg"; done ) \
 	-jvmArgs -Dorg.renaissance.jmh.configuration=test \
 	-jvmArgs -Dorg.renaissance.jmh.fakeIncompatible=true \
 	-wi 0 -i 1 -f 1 -foe true

tools/ci/common.sh

@@ -21,6 +21,12 @@ RENAISSANCE_GIT_VERSION=$(git describe --tags --always --dirty=-SNAPSHOT || echo
 # Strip leading 'v' from the git-produced version
 RENAISSANCE_VERSION=${RENAISSANCE_GIT_VERSION#v}
 
+# Try to guess JVM version
+RENAISSANCE_JVM_MAJOR_VERSION="$( java -XshowSettings:properties -version 2>&1 \
+    | sed -n -e 's#^[ \t]*java.version[ ]*=[ ]\(.*\)#\1#p' \
+    | sed -e 's#1\.8#8#' -e 's#\([^.]*\).*#\1#' \
+    || echo 8 )"
+
 # The base bundle
 RENAISSANCE_DIR="target"
 RENAISSANCE_JAR_NAME="renaissance-gpl-${RENAISSANCE_VERSION}.jar"
@@ -43,6 +49,15 @@ cp_reflink() {
 	cp $REFLINK "$@"
 }
 
+get_jvm_workaround_args() {
+    if [ "$RENAISSANCE_JVM_MAJOR_VERSION" = "16" ]; then
+        echo "--add-opens=java.base/java.lang.invoke=ALL-UNNAMED"
+        echo "--add-opens=java.base/java.util=ALL-UNNAME"
+        echo "--add-opens=java.base/java.nio=ALL-UNNAMED"
+        echo "--add-opens=java.base/sun.nio.ch=ALL-UNNAMED"
+    fi
+}
+
 
 # Make sure we are in the top-level directory so that we can use
 # relative paths when referring to files within the project.