TestOuterStripMinedDeadAfterExpansion.java

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.
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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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/**
 * @test
 * @bug 8253756
 * @summary dead outer strip mined not optimized out after expansion
 * @requires vm.compiler2.enabled
 *
 * @run main/othervm -XX:-BackgroundCompilation -XX:LoopMaxUnroll=2 TestOuterStripMinedDeadAfterExpansion
 *
 */

public class TestOuterStripMinedDeadAfterExpansion {
    private static int field;

    public static void main(String[] args) {
        int[] array = new int[100];
        for (int i = 0; i < 20_000; i++) {
            test(array, array, array.length);
            test_helper(array, 100);
        }
    }

    private static int test(int[] src, int[] dst, int length) {
        field = 4 << 17;
        System.arraycopy(src, 0, dst, 0, length);
        int stop = field >>> 17;
        return test_helper(dst, stop);
    }

    private static int test_helper(int[] dst, int stop) {
        int res = 0;
        for (int i = 0; i < stop; i++) {
            res += dst[i];
        }
        return res;
    }
}