/*

 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.

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

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * 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

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

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

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

import com.oracle.java.testlibrary.Asserts;

import com.oracle.java.testlibrary.Platform;

import java.util.stream.IntStream;

import sun.hotspot.WhiteBox;

public class CompilerUtils {

    private CompilerUtils() {

        // to prevent from instantiation

    }

    /**

     * Returns available compilation levels

     *

     * @return int array with compilation levels

     */

    public static int[] getAvailableCompilationLevels() {

        if (!WhiteBox.getWhiteBox().getBooleanVMFlag("UseCompiler")) {

            return new int[0];

        }

        if (WhiteBox.getWhiteBox().getBooleanVMFlag("TieredCompilation")) {

            Long flagValue = WhiteBox.getWhiteBox()

                    .getIntxVMFlag("TieredStopAtLevel");

            int maxLevel = flagValue.intValue();

            Asserts.assertEQ(new Long(maxLevel), flagValue,

                    "TieredStopAtLevel has value out of int capacity");

            return IntStream.rangeClosed(1, maxLevel).toArray();

        } else {

            if (Platform.isServer()) {

                return new int[]{4};

            }

            if (Platform.isClient() || Platform.isMinimal()) {

                return new int[]{1};

            }

        }

        return new int[0];

    }

}