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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

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 *

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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

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 *

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 * 2 along with this work; if not, write to the Free Software Foundation,

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/*

 * @test

 * @bug 8078262

 * @summary Tests correct dominator information after loop peeling.

 * @run main/othervm -Xcomp -XX:CompileCommand=compileonly,TestLoopPeeling::test* TestLoopPeeling

 */

public class TestLoopPeeling {

    public int[] array = new int[100];

    public static void main(String args[]) {

        TestLoopPeeling test = new TestLoopPeeling();

        try {

            test.testArrayAccess(0, 1);

            test.testArrayAllocation(0, 1);

        } catch (Exception e) {

            // Ignore exceptions

        }

    }

    public void testArrayAccess(int index, int inc) {

        int storeIndex = -1;

        for (; index < 10; index += inc) {

            // This loop invariant check triggers loop peeling because it can

            // be moved out of the loop (see 'IdealLoopTree::policy_peeling').

            if (inc == 42) return;

            // This loop variant usage of LShiftL( ConvI2L( Phi(storeIndex) ) )

            // prevents the split if optimization that would otherwise clone the

            // LShiftL and ConvI2L nodes and assign them to their corresponding array

            // address computation (see 'PhaseIdealLoop::split_if_with_blocks_post').

            if (storeIndex > 0 && array[storeIndex] == 42) return;

            if (index == 42) {

                // This store and the corresponding range check are moved out of the

                // loop and both used after old loop and the peeled iteration exit.

                // For the peeled iteration, storeIndex is always -1 and the ConvI2L

                // is replaced by TOP. However, the range check is not folded because

                // we don't do the split if optimization in PhaseIdealLoop2.

                // As a result, we have a (dead) control path from the peeled iteration

                // to the StoreI but the data path is removed.

                array[storeIndex] = 1;

                return;

            }

            storeIndex++;

        }

    }

    public byte[] testArrayAllocation(int index, int inc) {

        int allocationCount = -1;

        byte[] result;

        for (; index < 10; index += inc) {

            // This loop invariant check triggers loop peeling because it can

            // be moved out of the loop (see 'IdealLoopTree::policy_peeling').

            if (inc == 42) return null;

            if (index == 42) {

                // This allocation and the corresponding size check are moved out of the

                // loop and both used after old loop and the peeled iteration exit.

                // For the peeled iteration, allocationCount is always -1 and the ConvI2L

                // is replaced by TOP. However, the size check is not folded because

                // we don't do the split if optimization in PhaseIdealLoop2.

                // As a result, we have a (dead) control path from the peeled iteration

                // to the allocation but the data path is removed.

                result = new byte[allocationCount];

                return result;

            }

            allocationCount++;

        }

        return null;

    }

}