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

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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/**
 * @test
 * @bug 8069191
 * @summary predicate moved out of loops and CastPP removal causes dependency to be lost
 *
 * @run main/othervm -Xcomp -XX:+IgnoreUnrecognizedVMOptions -XX:+UnlockDiagnosticVMOptions -XX:+StressGCM
 *                   -XX:CompileCommand=compileonly,compiler.loopopts.TestPredicateLostDependency::m1
 *                   compiler.loopopts.TestPredicateLostDependency
 *
 */

package compiler.loopopts;

public class TestPredicateLostDependency {
    static class A {
        int i;
    }

    static class B extends A {
    }

    static boolean crash = false;

    static boolean m2() {
        return crash;
    }

    static int m3(float[] arr) {
        return 0;
    }

    static float m1(A aa) {
        float res = 0;
        float[] arr = new float[10];
        for (int i = 0; i < 10; i++) {
            if (m2()) {
                arr = null;
            }
            m3(arr);
            int j = arr.length;
            int k = 0;
            for (k = 9; k < j; k++) {
            }
            if (k == 10) {
                if (aa instanceof B) {
                }
            }
            res += arr[0];
            res += arr[1];
        }
        return res;
    }

    static public void main(String args[]) {
        A a = new A();
        B b = new B();
        for (int i = 0; i < 20000; i++) {
            m1(a);
        }
        crash = true;
        try {
            m1(a);
        } catch (NullPointerException npe) {}
    }
}