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

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/*
 * @test
 * @bug 8260370
 * @summary C2: LoopLimit node is not eliminated
 *
 * @run main/othervm
 *      -Xcomp
 *      -XX:CompileOnly=compiler/loopopts/TestLoopLimitNodeElimination
 *      compiler.loopopts.TestLoopLimitNodeElimination
 */

package compiler.loopopts;

// the test code is derived from a randomly generated test
public class TestLoopLimitNodeElimination {
    private static class MyException extends RuntimeException { }
    private static final int ITERATIONS = 100000;
    private static final int SIZE = 400;

    private static int counter = 0;

    int[] array1 = new int[SIZE];

    void test() {
        int[] array2 = new int[SIZE];
        array1[2] = 0;
        array1 = array1;
        for (long i = 301; i > 2; i -= 2) {
            int j = 1;
            do {
               for (int k = (int) i; k < 1; k++) { }
            } while (++j < 4);
        }

        counter++;
        if (counter == ITERATIONS) {
            throw new MyException();
        }
    }

    public static void main(String[] args) {
        try {
            var test = new TestLoopLimitNodeElimination();
            while (true) {
                test.test();
            }
        } catch (MyException e) {
            // expected
        }
    }
}