/*

 * Copyright (c) 2015, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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

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package jdk.nashorn.internal.ir;

import java.io.Serializable;

import java.util.List;

import jdk.nashorn.internal.codegen.CompileUnit;

/**

 * An interface for splittable expressions.

 */

public interface Splittable {

    /**

     * Get a list of split ranges for this splittable expression, or null

     * if the expression should not be split.

     *

     * @return a list of split ranges

     */

    List<SplitRange> getSplitRanges();

    /**

     * A SplitRange is a range in a splittable expression. It defines the

     * boundaries of the split range and provides a compile unit for code generation.

     */

    final class SplitRange implements CompileUnitHolder, Serializable {

        private static final long serialVersionUID = 1L;

        /** Compile unit associated with the postsets range. */

        private final CompileUnit compileUnit;

        /** postsets range associated with the unit (hi not inclusive). */

        private final int low, high;

        /**

         * Constructor

         * @param compileUnit compile unit

         * @param low lowest array index in unit

         * @param high highest array index in unit + 1

         */

        public SplitRange(final CompileUnit compileUnit, final int low, final int high) {

            this.compileUnit = compileUnit;

            this.low   = low;

            this.high   = high;

        }

        /**

         * Get the high index position of the ArrayUnit (exclusive)

         * @return high index position

         */

        public int getHigh() {

            return high;

        }

        /**

         * Get the low index position of the ArrayUnit (inclusive)

         * @return low index position

         */

        public int getLow() {

            return low;

        }

        /**

         * The array compile unit

         * @return array compile unit

         */

        @Override

        public CompileUnit getCompileUnit() {

            return compileUnit;

        }

    }

}