1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
|
/*
* Copyright (c) 2003, 2023, 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 8302040
* @key randomness
* @library /test/lib
* @build jdk.test.lib.RandomFactory
* @build Tests
* @build FdlibmTranslit
* @build SqrtTests
* @run main SqrtTests
* @summary Tests for StrictMath.sqrt
*/
import jdk.test.lib.RandomFactory;
/**
* The tests in ../Math/SqrtTests.java test properties that should
* hold for any sqrt implementation, including the FDLIBM-based one
* required for StrictMath.sqrt. Therefore, the test cases in
* ../Math/SqrtTests.java are run against both the Math and
* StrictMath versions of sqrt. The role of this test is to verify
* that the FDLIBM sqrt algorithm is being used by running golden
* file tests on values that may vary from one conforming sqrt
* implementation to another.
*/
public class SqrtTests {
private SqrtTests(){}
public static void main(String... args) {
int failures = 0;
failures += testAgainstTranslit();
if (failures > 0) {
System.err.println("Testing sqrt incurred "
+ failures + " failures.");
throw new RuntimeException();
}
}
// Initialize shared random number generator
private static java.util.Random random = RandomFactory.getRandom();
/**
* Test StrictMath.sqrt against transliteration port of sqrt.
*/
private static int testAgainstTranslit() {
int failures = 0;
double x;
// Test just above subnormal threshold...
x = Double.MIN_NORMAL;
failures += testRange(x, Math.ulp(x), 1000);
// ... and just below subnormal threshold ...
x = Math.nextDown(Double.MIN_NORMAL);
failures += testRange(x, -Math.ulp(x), 1000);
// ... and near 1.0 ...
failures += testRangeMidpoint(1.0, Math.ulp(x), 2000);
// (Note: probes every-other value less than 1.0 due to
// change in the size of an ulp at 1.0.
// Probe near decision points in the FDLIBM algorithm.
double[] decisionPoints = {
Double.MIN_VALUE,
Double.MAX_VALUE,
};
for (double testPoint : decisionPoints) {
failures += testRangeMidpoint(testPoint, Math.ulp(testPoint), 1000);
}
x = Tests.createRandomDouble(random);
// Make the increment twice the ulp value in case the random
// value is near an exponent threshold. Don't worry about test
// elements overflowing to infinity if the starting value is
// near Double.MAX_VALUE.
failures += testRange(x, 2.0 * Math.ulp(x), 1000);
return failures;
}
private static int testRange(double start, double increment, int count) {
int failures = 0;
double x = start;
for (int i = 0; i < count; i++, x += increment) {
failures += testSqrtCase(x, FdlibmTranslit.sqrt(x));
}
return failures;
}
private static int testRangeMidpoint(double midpoint, double increment, int count) {
int failures = 0;
double x = midpoint - increment*(count / 2) ;
for (int i = 0; i < count; i++, x += increment) {
failures += testSqrtCase(x, FdlibmTranslit.sqrt(x));
}
return failures;
}
private static int testSqrtCase(double input, double expected) {
return Tests.test("StrictMath.sqrt(double)", input,
StrictMath::sqrt, expected);
}
}
|
