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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * version 2 for more details (a copy is included in the LICENSE file that
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/**
 * @test
 * @bug 8356708
 * @summary C2: loop strip mining expansion doesn't take sunk stores into account
 *
 * @run main/othervm -XX:-TieredCompilation -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -XX:LoopMaxUnroll=0
 *                   -XX:+UnlockDiagnosticVMOptions -XX:+StressGCM -XX:StressSeed=26601954 TestStoresSunkInOuterStripMinedLoop
 * @run main/othervm -XX:-TieredCompilation -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -XX:LoopMaxUnroll=0
 *                   -XX:+UnlockDiagnosticVMOptions -XX:+StressGCM TestStoresSunkInOuterStripMinedLoop
 * @run main TestStoresSunkInOuterStripMinedLoop
 *
 */

public class TestStoresSunkInOuterStripMinedLoop {
    private static int field;
    private static volatile int volatileField;

    public static void main(String[] args) {
        A a1 = new A();
        A a2 = new A();
        A a3 = new A();
        for (int i = 0; i < 20_000; i++) {
            field = 0;
            test1();
            if (field != 1500) {
                throw new RuntimeException(field + " != 1500");
            }
            a1.field = 0;
            test2(a1, a2);
            if (a1.field != 1500) {
                throw new RuntimeException(a1.field + " != 1500");
            }
            a1.field = 0;
            test3(a1, a2);
            if (a1.field != 1500) {
                throw new RuntimeException(a1.field + " != 1500");
            }
            a1.field = 0;
            test4(a1, a2, a3);
            if (a1.field != 1500) {
                throw new RuntimeException(a1.field + " != 1500");
            }
        }
    }

    // Single store sunk in outer loop, no store in inner loop
    private static float test1() {
        int v = field;
        float f = 1;
        for (int i = 0; i < 1500; i++) {
            f *= 2;
            v++;
            field = v;
        }
        return f;
    }

    // Couple stores sunk in outer loop, no store in inner loop
    private static float test2(A a1, A a2) {
        field = a1.field + a2.field;
        volatileField = 42;
        int v = a1.field;
        float f = 1;
        for (int i = 0; i < 1500; i++) {
            f *= 2;
            v++;
            a1.field = v;
            a2.field = v;
        }
        return f;
    }

    // Store sunk in outer loop, store in inner loop
    private static float test3(A a1, A a2) {
        field = a1.field + a2.field;
        volatileField = 42;
        int v = a1.field;
        float f = 1;
        A a = a2;
        for (int i = 0; i < 1500; i++) {
            f *= 2;
            v++;
            a.field = v;
            a = a1;
            a2.field = v;
        }
        return f;
    }

    // Couples stores sunk in outer loop, store in inner loop
    private static float test4(A a1, A a2, A a3) {
        field = a1.field + a2.field + a3.field;
        volatileField = 42;
        int v = a1.field;
        float f = 1;
        A a = a2;
        for (int i = 0; i < 1500; i++) {
            f *= 2;
            v++;
            a.field = v;
            a = a1;
            a2.field = v;
            a3.field = v;
        }
        return f;
    }

    static class A {
        int field;
    }
}