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/**

 * @test

 * @bug 8230062

 * @summary The IR of this test contains a reduction chain which corresponds to a pack in which the 2nd last element has a usage outside of the optimized loop.

 *

 * @run main/othervm -Xbatch -XX:CompileCommand=compileonly,compiler.loopopts.superword.SuperWordIntermediateUse::test

 *      compiler.loopopts.superword.SuperWordIntermediateUse

 */

package compiler.loopopts.superword;

public class SuperWordIntermediateUse {

    private int iFld;

    private int[] iArr = new int[1024];

    public void test() {

        int local = 4;

        /**

         * Before unrolling this loop:

         * iFld:   AddI 1 = -85 + Phi 1

         * local:  MulI 2 = Phi 1 * LoadI 3

         *

         * This loop is now unrolled. 'local' is a reduction. The loop is first copied:

         * iFldCopy:  AddI C1 = -85 + Phi C1

         * localCopy: MulI C2 = Phi C1 * LoadI C3

         *

         * iFld:   AddI 1 = -85 + Phi 1

         * local:  MulI 2 = Phi 1 * LoadI 3

         *

         * Then, the unnecessary nodes like phis are removed from the original loop by igvn:

         * (iFldCopy:  AddI C1 = -85 + Phi C1) field store optimized away

         * localCopy: MulI C2 = Phi C1 * LoadI C3

         *

         * iFld:   AddI 1 = -85 + MulI C2

         * local:  MulI 2 = MulI C2 * LoadI 3 -> Input into Phi C1

         *

         *  As a result AddI 1 has an input from MulI C2 which isn't the last operation in the reduction chain

         *  Phi C1 -> MulI C2 -> MulI 2 -> Phi C1 and therefore not the last element in a pack.

         *  Additionally, AddI 1 does not belong to the loop being optimized: The store node for iFld is put outside of the loop being optimized.

         *  This triggers the assertion bug when unrolled at least 4 times which creates packs of at least size 4.

         */

        for (int i = 0; i < 1024; i++) {

            iFld = -85;

            iFld = iFld + local;

            local = local * iArr[i];

            iArr[i] = 3; // Just used to trigger SuperWord optimization

        }

    }

    public static void main(String[] strArr) {

        SuperWordIntermediateUse instance = new SuperWordIntermediateUse();

        for (int i = 0; i < 1000; i++) {

            instance.test();

        }

    }

}