/*

 * Copyright (c) 2011, 2013, 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.

 */

/*

 * @test

 * @bug 6430675 8010430

 * @summary Check for correct implementation of {Math, StrictMath}.round

 */

public class RoundTests {

    public static void main(String... args) {

        int failures = 0;

        failures += testNearFloatHalfCases();

        failures += testNearDoubleHalfCases();

        failures += testUnityULPCases();

        failures += testSpecialCases();

        if (failures > 0) {

            System.err.println("Testing {Math, StrictMath}.round incurred "

                               + failures + " failures.");

            throw new RuntimeException();

        }

    }

    private static int testNearDoubleHalfCases() {

        int failures = 0;

        double [][] testCases = {

            {+0x1.fffffffffffffp-2,  0.0},

            {+0x1.0p-1,              1.0}, // +0.5

            {+0x1.0000000000001p-1,  1.0},

            {-0x1.fffffffffffffp-2,  0.0},

            {-0x1.0p-1,              0.0}, // -0.5

            {-0x1.0000000000001p-1, -1.0},

        };

        for(double[] testCase : testCases) {

            failures += testNearHalfCases(testCase[0], (long)testCase[1]);

        }

        return failures;

    }

    private static int testNearHalfCases(double input, double expected) {

        int failures = 0;

        failures += Tests.test("Math.round",        input, Math.round(input),       expected);

        failures += Tests.test("StrictMath.round",  input, StrictMath.round(input), expected);

        return failures;

    }

    private static int testNearFloatHalfCases() {

        int failures = 0;

        float [][] testCases = {

            {+0x1.fffffep-2f,  0.0f},

            {+0x1.0p-1f,       1.0f}, // +0.5

            {+0x1.000002p-1f,  1.0f},

            {-0x1.fffffep-2f,  0.0f},

            {-0x1.0p-1f,       0.0f}, // -0.5

            {-0x1.000002p-1f, -1.0f},

        };

        for(float[] testCase : testCases) {

            failures += testNearHalfCases(testCase[0], (int)testCase[1]);

        }

        return failures;

    }

    private static int testNearHalfCases(float input, float expected) {

        int failures = 0;

        failures += Tests.test("Math.round",        input, Math.round(input),       expected);

        failures += Tests.test("StrictMath.round",  input, StrictMath.round(input), expected);

        return failures;

    }

    private static int testUnityULPCases() {

        int failures = 0;

        for (float sign : new float[]{-1, 1}) {

            for (float v1 : new float[]{1 << 23, 1 << 24}) {

                for (int k = -5; k <= 5; k++) {

                    float value = (v1 + k) * sign;

                    float actual = Math.round(value);

                    failures += Tests.test("Math.round", value, actual, value);

                }

            }

        }

        if (failures != 0) {

            System.out.println();

        }

        for (double sign : new double[]{-1, 1}) {

            for (double v1 : new double[]{1L << 52, 1L << 53}) {

                for (int k = -5; k <= 5; k++) {

                    double value = (v1 + k) * sign;

                    double actual = Math.round(value);

                    failures += Tests.test("Math.round", value, actual, value);

                }

            }

        }

        return failures;

    }

    private static int testSpecialCases() {

        int failures = 0;

        failures += Tests.test("Math.round", Float.NaN, Math.round(Float.NaN), 0.0F);

        failures += Tests.test("Math.round", Float.POSITIVE_INFINITY,

                Math.round(Float.POSITIVE_INFINITY), Integer.MAX_VALUE);

        failures += Tests.test("Math.round", Float.NEGATIVE_INFINITY,

                Math.round(Float.NEGATIVE_INFINITY), Integer.MIN_VALUE);

        failures += Tests.test("Math.round", -(float)Integer.MIN_VALUE,

                Math.round(-(float)Integer.MIN_VALUE), Integer.MAX_VALUE);

        failures += Tests.test("Math.round", (float) Integer.MIN_VALUE,

                Math.round((float) Integer.MIN_VALUE), Integer.MIN_VALUE);

        failures += Tests.test("Math.round", 0F, Math.round(0F), 0.0F);

        failures += Tests.test("Math.round", Float.MIN_VALUE,

                Math.round(Float.MIN_VALUE), 0.0F);

        failures += Tests.test("Math.round", -Float.MIN_VALUE,

                Math.round(-Float.MIN_VALUE), 0.0F);

        failures += Tests.test("Math.round", Double.NaN, Math.round(Double.NaN), 0.0);

        failures += Tests.test("Math.round", Double.POSITIVE_INFINITY,

                Math.round(Double.POSITIVE_INFINITY), Long.MAX_VALUE);

        failures += Tests.test("Math.round", Double.NEGATIVE_INFINITY,

                Math.round(Double.NEGATIVE_INFINITY), Long.MIN_VALUE);

        failures += Tests.test("Math.round", -(double)Long.MIN_VALUE,

                Math.round(-(double)Long.MIN_VALUE), Long.MAX_VALUE);

        failures += Tests.test("Math.round", (double) Long.MIN_VALUE,

                Math.round((double) Long.MIN_VALUE), Long.MIN_VALUE);

        failures += Tests.test("Math.round", 0, Math.round(0), 0.0);

        failures += Tests.test("Math.round", Double.MIN_VALUE,

                Math.round(Double.MIN_VALUE), 0.0);

        failures += Tests.test("Math.round", -Double.MIN_VALUE,

                Math.round(-Double.MIN_VALUE), 0.0);

        return failures;

    }

}