1 /*

     2  * Copyright 2005 Sun Microsystems, Inc.  All Rights Reserved.

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

     4  *

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

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

     7  * published by the Free Software Foundation.

     8  *

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

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

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

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

    13  * accompanied this code).

    14  *

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

    16  * 2 along with this work; if not, write to the Free Software Foundation,

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

    18  *

    19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    20  * CA 95054 USA or visit www.sun.com if you need additional information or

    21  * have any questions.

    22  */

    23 

    24 /*

    25  * @test

    26  * @bug 5037596

    27  * @summary Verify bitwise conversion works for non-canonical NaN values

    28  * @author Joseph D. Darcy

    29  */

    30 

    31 import static java.lang.Float.*;

    32 import static sun.misc.FloatConsts.*;

    33 

    34 public class BitwiseConversion {

    35     static int testNanCase(int x) {

    36         int errors  = 0;

    37         // Strip out sign and exponent bits

    38         int y = x & SIGNIF_BIT_MASK;

    39 

    40         float values[] = {

    41             intBitsToFloat(EXP_BIT_MASK | y),

    42             intBitsToFloat(SIGN_BIT_MASK | EXP_BIT_MASK | y)

    43         };

    44 

    45         for(float value: values) {

    46             if (!isNaN(value)) {

    47                 throw new RuntimeException("Invalid input " + y +

    48                                            "yielded non-NaN" + value);

    49             }

    50             int converted = floatToIntBits(value);

    51             if (converted != 0x7fc00000) {

    52                 errors++;

    53                 System.err.format("Non-canoncial NaN bits returned: %x%n",

    54                                   converted);

    55             }

    56         }

    57         return errors;

    58     }

    59 

    60     public static void main(String... argv) {

    61         int errors = 0;

    62 

    63         for (int i = 0; i < SIGNIFICAND_WIDTH-1; i++) {

    64             errors += testNanCase(1<<i);

    65         }

    66 

    67         if (floatToIntBits(Float.POSITIVE_INFINITY)

    68                 != 0x7F800000) {

    69             errors++;

    70             System.err.println("Bad conversion for +infinity.");

    71         }

    72 

    73         if (floatToIntBits(Float.NEGATIVE_INFINITY)

    74                 != 0xFF800000) {

    75             errors++;

    76             System.err.println("Bad conversion for -infinity.");

    77         }

    78 

    79         if (errors > 0)

    80             throw new RuntimeException();

    81     }

    82 }