1 /*
   2  * Copyright (c) 2005, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /*
  25  * @test
  26  * @bug 5037596
  27  * @summary Verify bitwise conversion works for non-canonical NaN values
  28  * @library /lib/testlibrary
  29  * @build jdk.testlibrary.DoubleUtils
  30  * @run main BitwiseConversion
  31  * @author Joseph D. Darcy
  32  */
  33 
  34 import static java.lang.Double.*;
  35 import static jdk.testlibrary.DoubleUtils.*;
  36 
  37 public class BitwiseConversion {
  38     static int testNanCase(long x) {
  39         int errors  = 0;
  40         // Strip out sign and exponent bits
  41         long y = x & SIGNIF_BIT_MASK;
  42 
  43         double values[] = {
  44             longBitsToDouble(EXP_BIT_MASK | y),
  45             longBitsToDouble(SIGN_BIT_MASK | EXP_BIT_MASK | y)
  46         };
  47 
  48         for(double value: values) {
  49             if (!isNaN(value)) {
  50                 throw new RuntimeException("Invalid input " + y +
  51                                            "yielded non-NaN" + value);
  52             }
  53             long converted = doubleToLongBits(value);
  54             if (converted != 0x7ff8000000000000L) {
  55                 errors++;
  56                 System.err.format("Non-canoncial NaN bits returned: %x%n",
  57                                   converted);
  58             }
  59         }
  60         return errors;
  61     }
  62 
  63     public static void main(String... argv) {
  64         int errors = 0;
  65 
  66         for (int i = 0; i < SIGNIFICAND_WIDTH-1; i++) {
  67             errors += testNanCase(1L<<i);
  68         }
  69 
  70         if (doubleToLongBits(Double.POSITIVE_INFINITY)
  71                 != 0x7ff0000000000000L) {
  72             errors++;
  73             System.err.println("Bad conversion for +infinity.");
  74         }
  75 
  76         if (doubleToLongBits(Double.NEGATIVE_INFINITY)
  77                 != 0xfff0000000000000L) {
  78             errors++;
  79             System.err.println("Bad conversion for -infinity.");
  80         }
  81 
  82         if (errors > 0)
  83             throw new RuntimeException();
  84     }
  85 }