Testing observed a NPE in java.time.ZoneId.systemDefault() after C2 compilation.

import java.io.IOException;
import java.time.ZoneId;
import java.util.TimeZone;

public class CloneBug {

    static final TimeZone UTC = TimeZone.getTimeZone("UTC");

    static void test() {
        TimeZone.setDefault(UTC);
        for (int i = 0; i < 16801; i++) {
            ZoneId.systemDefault();
        }
    }

    public static void main(String[] args) throws IOException {
        for (int i = 0; i < 100; i++) {
            test();
        }
    }
}

Expected output: Nothing
Actual output:
Exception in thread "main" java.lang.NullPointerException
at java.util.TimeZone.toZoneId0(TimeZone.java:560)
at java.util.TimeZone.toZoneId(TimeZone.java:550)
at java.time.ZoneId.systemDefault(ZoneId.java:274)
at CloneBug.test(CloneBug.java:13)
at CloneBug.main(CloneBug.java:19)

Supplying any of the following avoids the issue:
-Xint
-XX:-DoEscapeAnalysis
-XX:+UnlockDiagnosticVMOptions -XX:DisableIntrinsic=_clone
-XX:TieredStopAtLevel=1

Issue still reproduce using:
-XX:-TieredCompilation

Issue narrowed down to 9-b66, still exists in 9-b71

ILW = Unavoidable exceptions in compiled code (H), heavy use of publicly available method used internally in the JDK will trigger (H), disabling escape analysis avoids issue entirely (L) = HHL = P2