| /* |
| * Copyright (c) 2015, 2017, 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 8139688 |
| * @key randomness |
| * @library /test/lib |
| * @build jdk.test.lib.RandomFactory |
| * @build Tests |
| * @build FdlibmTranslit |
| * @build ExpTests |
| * @run main ExpTests |
| * @summary Tests specifically for StrictMath.exp |
| */ |
| |
| import jdk.test.lib.RandomFactory; |
| |
| /** |
| * The role of this test is to verify that the FDLIBM exp algorithm is |
| * being used by running golden file style tests on values that may |
| * vary from one conforming exponential implementation to another. |
| */ |
| |
| public class ExpTests { |
| private ExpTests(){} |
| |
| public static void main(String [] argv) { |
| int failures = 0; |
| |
| failures += testExp(); |
| failures += testAgainstTranslit(); |
| |
| if (failures > 0) { |
| System.err.println("Testing the exponential incurred " |
| + failures + " failures."); |
| throw new RuntimeException(); |
| } |
| } |
| |
| // From the fdlibm source, the overflow threshold in hex is: |
| // 0x4086_2E42_FEFA_39EF. |
| static final double EXP_OVERFLOW_THRESH = Double.longBitsToDouble(0x4086_2E42_FEFA_39EFL); |
| |
| // From the fdlibm source, the underflow threshold in hex is: |
| // 0xc087_4910_D52D_3051L. |
| static final double EXP_UNDERFLOW_THRESH = Double.longBitsToDouble(0xc087_4910_D52D_3051L); |
| |
| static int testExp() { |
| int failures = 0; |
| |
| double [][] testCases = { |
| // Some of these could be moved to common Math/StrictMath exp testing. |
| {Double.NaN, Double.NaN}, |
| {Double.MAX_VALUE, Double.POSITIVE_INFINITY}, |
| {Double.POSITIVE_INFINITY, Double.POSITIVE_INFINITY}, |
| {Double.NEGATIVE_INFINITY, +0.0}, |
| {EXP_OVERFLOW_THRESH, 0x1.ffff_ffff_fff2ap1023}, |
| {Math.nextUp(EXP_OVERFLOW_THRESH), Double.POSITIVE_INFINITY}, |
| {Math.nextDown(EXP_UNDERFLOW_THRESH), +0.0}, |
| {EXP_UNDERFLOW_THRESH, +Double.MIN_VALUE}, |
| }; |
| |
| for(double[] testCase: testCases) |
| failures+=testExpCase(testCase[0], testCase[1]); |
| |
| return failures; |
| } |
| |
| static int testExpCase(double input, double expected) { |
| int failures = 0; |
| |
| failures+=Tests.test("StrictMath.exp(double)", input, |
| StrictMath.exp(input), expected); |
| return failures; |
| } |
| |
| // Initialize shared random number generator |
| private static java.util.Random random = RandomFactory.getRandom(); |
| |
| /** |
| * Test StrictMath.exp against transliteration port of exp. |
| */ |
| private static int testAgainstTranslit() { |
| int failures = 0; |
| |
| double[] decisionPoints = { |
| // Near overflow threshold |
| EXP_OVERFLOW_THRESH - 512*Math.ulp(EXP_OVERFLOW_THRESH), |
| |
| // Near underflow threshold |
| EXP_UNDERFLOW_THRESH - 512*Math.ulp(EXP_UNDERFLOW_THRESH), |
| |
| // Straddle algorithm conditional checks |
| Double.longBitsToDouble(0x4086_2E42_0000_0000L - 512L), |
| Double.longBitsToDouble(0x3fd6_2e42_0000_0000L - 512L), |
| Double.longBitsToDouble(0x3FF0_A2B2_0000_0000L - 512L), |
| Double.longBitsToDouble(0x3e30_0000_0000_0000L - 512L), |
| |
| // Other notable points |
| Double.MIN_NORMAL - Math.ulp(Double.MIN_NORMAL)*512, |
| -Double.MIN_VALUE*512, |
| }; |
| |
| for (double decisionPoint : decisionPoints) { |
| double ulp = Math.ulp(decisionPoint); |
| failures += testRange(decisionPoint - 1024*ulp, ulp, 1_024); |
| } |
| |
| // Try out some random values |
| for (int i = 0; i < 100; i++) { |
| double x = Tests.createRandomDouble(random); |
| failures += testRange(x, Math.ulp(x), 100); |
| } |
| |
| 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 += testExpCase(x, FdlibmTranslit.Exp.compute(x)); |
| } |
| return failures; |
| } |
| } |