/*

 * 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.

 *

 * 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 8073670

 * @summary Test that causes C2 to fold two NaNs with different values into a single NaN.

 *

 * @run main/othervm -XX:-TieredCompilation -Xcomp

 *      -XX:CompileCommand=compileonly,compiler.c2.FloatingPointFoldingTest::test_double_inf

 *      -XX:CompileCommand=compileonly,compiler.c2.FloatingPointFoldingTest::test_double_zero

 *      -XX:CompileCommand=compileonly,compiler.c2.FloatingPointFoldingTest::test_double_nan

 *      -XX:CompileCommand=compileonly,compiler.c2.FloatingPointFoldingTest::test_float_inf

 *      -XX:CompileCommand=compileonly,compiler.c2.FloatingPointFoldingTest::test_float_zero

 *      -XX:CompileCommand=compileonly,compiler.c2.FloatingPointFoldingTest::test_float_nan

 *      compiler.c2.FloatingPointFoldingTest

 */

package compiler.c2;

public class FloatingPointFoldingTest {

    // Double values.

    public static final long MINUS_INF_LONGBITS = 0xfff0000000000000L;

    public static final double DOUBLE_MINUS_INF = Double.longBitsToDouble(MINUS_INF_LONGBITS);

    public static final long PLUS_INF_LONGBITS = 0x7ff0000000000000L;

    public static final double DOUBLE_PLUS_INF = Double.longBitsToDouble(PLUS_INF_LONGBITS);

    public static final long MINUS_ZERO_LONGBITS = 0x8000000000000000L;

    public static final double DOUBLE_MINUS_ZERO = Double.longBitsToDouble(MINUS_ZERO_LONGBITS);

    // We need two different NaN values. A floating point number is

    // considered to be NaN is the sign bit is 0, all exponent bits

    // are set to 1, and at least one bit of the exponent is not zero.

    //

    // As java.lang.Double.NaN is 0x7ff8000000000000L, we use

    // 0x7ffc000000000000L as a second NaN double value.

    public static final long NAN_LONGBITS = 0x7ffc000000000000L;

    public static final double DOUBLE_NAN = Double.longBitsToDouble(NAN_LONGBITS);

    // Float values.

    public static final int MINUS_INF_INTBITS = 0xff800000;

    public static final float FLOAT_MINUS_INF = Float.intBitsToFloat(MINUS_INF_INTBITS);

    public static final int PLUS_INF_INTBITS = 0x7f800000;

    public static final float FLOAT_PLUS_INF = Float.intBitsToFloat(PLUS_INF_INTBITS);

    public static final int MINUS_ZERO_INTBITS = 0x80000000;

    public static final float FLOAT_MINUS_ZERO = Float.intBitsToFloat(MINUS_ZERO_INTBITS);

    // As java.lang.Float.NaN is 0x7fc00000, we use 0x7fe00000

    // as a second NaN float value.

    public static final int NAN_INTBITS = 0x7fe00000;

    public static final float FLOAT_NAN = Float.intBitsToFloat(NAN_INTBITS);

    // Double tests.

    static void test_double_inf(long[] result) {

        double d1 = DOUBLE_MINUS_INF;

        double d2 = DOUBLE_PLUS_INF;

        result[0] = Double.doubleToRawLongBits(d1);

        result[1] = Double.doubleToRawLongBits(d2);

    }

    static void test_double_zero(long[] result) {

        double d1 = DOUBLE_MINUS_ZERO;

        double d2 = 0;

        result[0] = Double.doubleToRawLongBits(d1);

        result[1] = Double.doubleToRawLongBits(d2);

    }

    static void test_double_nan(long[] result) {

        double d1 = DOUBLE_NAN;

        double d2 = Double.NaN;

        result[0] = Double.doubleToRawLongBits(d1);

        result[1] = Double.doubleToRawLongBits(d2);

    }

    // Float tests.

    static void test_float_inf(int[] result) {

        float f1 = FLOAT_MINUS_INF;

        float f2 = FLOAT_PLUS_INF;

        result[0] = Float.floatToRawIntBits(f1);

        result[1] = Float.floatToRawIntBits(f2);

    }

    static void test_float_zero(int[] result) {

        float f1 = FLOAT_MINUS_ZERO;

        float f2 = 0;

        result[0] = Float.floatToRawIntBits(f1);

        result[1] = Float.floatToRawIntBits(f2);

    }

    static void test_float_nan(int[] result) {

        float f1 = FLOAT_NAN;

        float f2 = Float.NaN;

        result[0] = Float.floatToRawIntBits(f1);

        result[1] = Float.floatToRawIntBits(f2);

    }

    // Check doubles.

    static void check_double(long[] result, double d1, double d2) {

        if (result[0] == result[1]) {

            throw new RuntimeException("ERROR: Two different double values are considered equal. \n"

                                       + String.format("\toriginal values: 0x%x 0x%x\n", Double.doubleToRawLongBits(d1), Double.doubleToRawLongBits(d2))

                                       + String.format("\tvalues after execution of method test(): 0x%x 0x%x", result[0], result[1]));

        }

    }

    // Check floats.

    static void check_float(int[] result, float f1, float f2) {

        if (result[0] == result[1]) {

            throw new RuntimeException("ERROR: Two different float values are considered equal. \n"

                                       + String.format("\toriginal values: 0x%x 0x%x\n", Float.floatToRawIntBits(f1), Float.floatToRawIntBits(f2))

                                       + String.format("\tvalues after execution of method test(): 0x%x 0x%x", result[0], result[1]));

        }

    }

    public static void main(String[] args) {

        // Float tests.

        int[] iresult = new int[2];

        // -Inf and +Inf.

        test_float_inf(iresult);

        check_float(iresult, FLOAT_MINUS_INF, FLOAT_PLUS_INF);

        // 0 and -0.

        test_float_zero(iresult);

        check_float(iresult, FLOAT_MINUS_ZERO, 0);

        // Diferrent NaNs.

        test_float_nan(iresult);

        check_float(iresult, FLOAT_NAN, Float.NaN);

        // Double tests.

        long[] lresult = new long[2];

        // -Inf and +Inf.

        test_double_inf(lresult);

        check_double(lresult, DOUBLE_MINUS_INF, DOUBLE_PLUS_INF);

        // 0 and -0.

        test_double_zero(lresult);

        check_double(lresult, DOUBLE_MINUS_ZERO, 0);

        // Diferrent NaNs.

        test_double_nan(lresult);

        check_double(lresult, DOUBLE_NAN, Double.NaN);

    }

}