1/* 2 * Copyright (c) 2016, 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 8160425 27 * @summary Test vectorization with a signalling NaN. 28 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-OptimizeFill 29 * compiler.vectorization.TestNaNVector 30 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-OptimizeFill 31 * -XX:MaxVectorSize=4 compiler.vectorization.TestNaNVector 32 */ 33 34package compiler.vectorization; 35 36public class TestNaNVector { 37 private char[] array; 38 private static final int LEN = 1024; 39 40 public static void main(String args[]) { 41 TestNaNVector test = new TestNaNVector(); 42 // Check double precision NaN 43 for (int i = 0; i < 10_000; ++i) { 44 test.vectorizeNaNDP(); 45 } 46 System.out.println("Checking double precision Nan"); 47 test.checkResult(0xfff7); 48 49 // Check single precision NaN 50 for (int i = 0; i < 10_000; ++i) { 51 test.vectorizeNaNSP(); 52 } 53 System.out.println("Checking single precision Nan"); 54 test.checkResult(0xff80); 55 } 56 57 public TestNaNVector() { 58 array = new char[LEN]; 59 } 60 61 public void vectorizeNaNDP() { 62 // This loop will be vectorized and the array store will be replaced by 63 // a 64-bit vector store to four subsequent array elements. The vector 64 // should look like this '0xfff7fff7fff7fff7' and is read from the constant 65 // table. However, in floating point arithmetic this is a signalling NaN 66 // which may be converted to a quiet NaN when processed by the x87 FPU. 67 // If the signalling bit is set, the vector ends up in the constant table 68 // as '0xfffffff7fff7fff7' which leads to an incorrect result. 69 for (int i = 0; i < LEN; ++i) { 70 array[i] = 0xfff7; 71 } 72 } 73 74 public void vectorizeNaNSP() { 75 // Same as above but with single precision 76 for (int i = 0; i < LEN; ++i) { 77 array[i] = 0xff80; 78 } 79 } 80 81 public void checkResult(int expected) { 82 for (int i = 0; i < LEN; ++i) { 83 if (array[i] != expected) { 84 throw new RuntimeException("Invalid result: array[" + i + "] = " + (int)array[i] + " != " + expected); 85 } 86 } 87 } 88} 89 90