1 /*
2 * Copyright (c) 1998, 2011, 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 4101566 4831589
27 * @summary Check for correct implementation of Math.rint(double)
28 */
29
30 import sun.misc.DoubleConsts;
31
32 public class Rint {
33
34 static int testRintCase(double input, double expected) {
35 int failures = 0;
36 double result;
37 failures += Tests.test("Math.rint", input, Math.rint(input), expected);
38 failures += Tests.test("Math.rint", -input, Math.rint(-input), -expected);
39 failures += Tests.test("StrictMath.rint",
40 input, StrictMath.rint(input), expected);
41 failures += Tests.test("StrictMath.rint", -input,
42 StrictMath.rint(-input), -expected);
43 return failures;
44 }
45
46
47 public static void main(String args[]) {
48 int failures = 0;
49 double twoToThe52 = Math.scalb(1.0, 52); // 2^52
50
51 double [][] testCases = {
52 {0.0, 0.0},
53 {Double.MIN_VALUE, 0.0},
54 {Math.nextDown(DoubleConsts.MIN_NORMAL), 0.0},
55 {DoubleConsts.MIN_NORMAL, 0.0},
56
57 {0.2, 0.0},
58
59 {Math.nextDown(0.5), 0.0},
60 { 0.5, 0.0},
61 { Math.nextUp(0.5), 1.0},
62
63 {0.7, 1.0},
64 {Math.nextDown(1.0), 1.0},
65 { 1.0, 1.0},
66 { Math.nextUp(1.0), 1.0},
67
68 {Math.nextDown(1.5), 1.0},
69 { 1.5, 2.0},
70 { Math.nextUp(1.5), 2.0},
71
72 {4.2, 4.0},
73 {4.5, 4.0},
74 {4.7, 5.0},
75
76 {7.5, 8.0},
77 {7.2, 7.0},
78 {7.7, 8.0},
79
80 {150000.75, 150001.0},
81 {300000.5, 300000.0},
82 {Math.nextUp(300000.5), 300001.0},
83 {Math.nextDown(300000.75), 300001.0},
84 {300000.75, 300001.0},
85 {Math.nextUp(300000.75), 300001.0},
86 {300000.99, 300001.0},
87 {262144.75, 262145.0}, //(2^18 ) + 0.75
88 {499998.75, 499999.0},
89 {524287.75, 524288.0}, //(2^19 -1) + 0.75
90 {524288.75, 524289.0},
91
92 {Math.nextDown(twoToThe52), twoToThe52},
93 {twoToThe52, twoToThe52},
94 {Math.nextUp(twoToThe52), Math.nextUp(twoToThe52)},
95
96 {Double.MAX_VALUE, Double.MAX_VALUE},
97 {Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY},
98 {Double.NaN, Double.NaN}
99
100 };
101
102
103 for(int i = 0; i < testCases.length; i++) {
104 failures += testRintCase(testCases[i][0], testCases[i][1]);
105 }
106
107 // Test values throughout exponent range
108 for(double d = Double.MIN_VALUE;
109 d < Double.POSITIVE_INFINITY; d *= 2) {
110 failures += testRintCase(d, ((d<=0.5)?0.0:d));
111 }
112
113 if (failures > 0) {
114 System.err.println("Testing {Math, StrictMath}.rint incurred "
115 + failures + " failures.");
116 throw new RuntimeException();
117 }
118 }
119 }