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 * @library /lib/testlibrary
29 * @build jdk.testlibrary.DoubleUtils jdk.testlibrary.FloatUtils
30 * @run main Rint
31 */
32
33 public class Rint {
34
35 static int testRintCase(double input, double expected) {
36 int failures = 0;
37 double result;
38 failures += Tests.test("Math.rint", input, Math.rint(input), expected);
39 failures += Tests.test("Math.rint", -input, Math.rint(-input), -expected);
40 failures += Tests.test("StrictMath.rint",
41 input, StrictMath.rint(input), expected);
42 failures += Tests.test("StrictMath.rint", -input,
43 StrictMath.rint(-input), -expected);
44 return failures;
45 }
46
47
48 public static void main(String args[]) {
49 int failures = 0;
50 double twoToThe52 = Math.scalb(1.0, 52); // 2^52
51
52 double [][] testCases = {
53 {0.0, 0.0},
54 {Double.MIN_VALUE, 0.0},
55 {Math.nextDown(Double.MIN_NORMAL), 0.0},
56 {Double.MIN_NORMAL, 0.0},
57
58 {0.2, 0.0},
59
60 {Math.nextDown(0.5), 0.0},
61 { 0.5, 0.0},
62 { Math.nextUp(0.5), 1.0},
63
64 {0.7, 1.0},
65 {Math.nextDown(1.0), 1.0},
66 { 1.0, 1.0},
67 { Math.nextUp(1.0), 1.0},
68
69 {Math.nextDown(1.5), 1.0},
70 { 1.5, 2.0},
71 { Math.nextUp(1.5), 2.0},
72
73 {4.2, 4.0},
74 {4.5, 4.0},
75 {4.7, 5.0},
76
77 {7.5, 8.0},
78 {7.2, 7.0},
79 {7.7, 8.0},
80
81 {150000.75, 150001.0},
82 {300000.5, 300000.0},
83 {Math.nextUp(300000.5), 300001.0},
84 {Math.nextDown(300000.75), 300001.0},
85 {300000.75, 300001.0},
86 {Math.nextUp(300000.75), 300001.0},
87 {300000.99, 300001.0},
88 {262144.75, 262145.0}, //(2^18 ) + 0.75
89 {499998.75, 499999.0},
90 {524287.75, 524288.0}, //(2^19 -1) + 0.75
91 {524288.75, 524289.0},
92
93 {Math.nextDown(twoToThe52), twoToThe52},
94 {twoToThe52, twoToThe52},
95 {Math.nextUp(twoToThe52), Math.nextUp(twoToThe52)},
96
97 {Double.MAX_VALUE, Double.MAX_VALUE},
98 {Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY},
99 {Double.NaN, Double.NaN}
100
101 };
102
103
104 for(int i = 0; i < testCases.length; i++) {
105 failures += testRintCase(testCases[i][0], testCases[i][1]);
106 }
107
108 // Test values throughout exponent range
109 for(double d = Double.MIN_VALUE;
110 d < Double.POSITIVE_INFINITY; d *= 2) {
111 failures += testRintCase(d, ((d<=0.5)?0.0:d));
112 }
113
114 if (failures > 0) {
115 System.err.println("Testing {Math, StrictMath}.rint incurred "
116 + failures + " failures.");
117 throw new RuntimeException();
118 }
119 }
120 }