jdk/test/hotspot/jtreg/compiler/loopopts/VerifyGraphEdgesWithDeadCodeCheckFromSafepoints.java

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/**
 * @test
 * @bug 8335708
 * @summary Crash Compile::verify_graph_edges with dead code check when safepoints are reachable but not connected back to Root's inputs
 * @library /test/lib
 *
 * @run driver compiler.loopopts.VerifyGraphEdgesWithDeadCodeCheckFromSafepoints
 * @run main/othervm
 *       -XX:+IgnoreUnrecognizedVMOptions -XX:+UnlockDiagnosticVMOptions
 *       -XX:-TieredCompilation -XX:+VerifyGraphEdges
 *       -XX:+StressIGVN -Xcomp
 *       -XX:CompileCommand=compileonly,compiler.loopopts.VerifyGraphEdgesWithDeadCodeCheckFromSafepoints::mainTest
 *       compiler.loopopts.VerifyGraphEdgesWithDeadCodeCheckFromSafepoints
 *
 */

package compiler.loopopts;

import jdk.test.lib.Utils;

public class VerifyGraphEdgesWithDeadCodeCheckFromSafepoints {
    public static void main(String[] args) throws Exception {
        Thread thread = new Thread() {
            public void run() {
                VerifyGraphEdgesWithDeadCodeCheckFromSafepoints instance = new VerifyGraphEdgesWithDeadCodeCheckFromSafepoints();
                byte[] a = new byte[997];
                for (int i = 0; i < 100; ++i) {
                    instance.mainTest(a, a);
                }
            }
        };
        // Give thread some time to trigger compilation
        thread.setDaemon(true);
        thread.start();
        Thread.sleep(Utils.adjustTimeout(500));
    }

    public void mainTest(byte[] a, byte[] b) {
        int i = 0;
        while (i < (a.length - 4)) {
            a[i] = b[i];
        }
        while (true) {
            a[i] = b[i];
        }
    }
}