test/hotspot/jtreg/compiler/c2/TestUnreachableRegionDuringCCP.java

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/**
 * @test
 * @bug 8210387
 * @summary Test removal of unreachable regions during CCP.
 * @library /test/lib
 * @run main/othervm -Xcomp -XX:-TieredCompilation
 *                   -XX:CompileOnly=compiler.c2.TestUnreachableRegionDuringCCP::test
 *                   compiler.c2.TestUnreachableRegionDuringCCP
 */

package compiler.c2;

import jdk.test.lib.Asserts;

public class TestUnreachableRegionDuringCCP {
    static int iFld1 = -1;
    static int iFld2 = -1;
    static int iArrFld[] = new int[100];

    public static void test() {
        int i = 1;
        do {
            iArrFld[i] = iFld1;
            iFld1 = 42;
            for (int j = 1; j < 5; j++) {
                if (i != 0) {
                    return; // Always returns
                }
                iFld2 += j;
            }
        } while (++i < 10);
    }

    public static void main(String[] args) {
        test();
        Asserts.assertEQ(iFld1, 42);
        Asserts.assertEQ(iFld2, -1);
        Asserts.assertEQ(iArrFld[1], -1);
    }
}