test/hotspot/jtreg/compiler/loopopts/TestDeepGraphVerifyIterativeGVN.java

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/**
 * @test
 * @bug 8246203
 * @requires vm.debug == true & vm.flavor == "server"
 * @summary Test which causes a stack overflow segmentation fault with -XX:+VerifyIterativeGVN due to a too deep recursion in Node::verify_recur().
 *
 * @run main/othervm/timeout=600 -Xcomp -XX:+VerifyIterativeGVN -XX:CompileCommand=compileonly,compiler.loopopts.TestDeepGraphVerifyIterativeGVN::*
 *                               compiler.loopopts.TestDeepGraphVerifyIterativeGVN
 */

package compiler.loopopts;

public class TestDeepGraphVerifyIterativeGVN
{
    static volatile int[] iArr;
    static volatile int x;

    public static void main(String[] arr) {
        /*
         * Just enough statements to create a deep enough graph (i.e. many nodes in one chain). The current recursive verification in Node::verify_recur() will follow this chain
         * and call itself again for each newly discovered input node. The current implementation can only handle up to around 10000 recursive calls and will then crash with a
         * stack overflow segementation fault. The iterative fix needs much less memory and does not result in a segementation fault anymore.
         */
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
        iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 }; iArr = new int[] { x % 2 };
    }
}