1 /* 2 * Copyright (c) 2018, Red Hat Inc. 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 8204479 27 * @summary Bitwise AND on byte value sometimes produces wrong result 28 * 29 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-TieredCompilation 30 * -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -Xcomp -XX:-Inline 31 * compiler.c2.TestUnsignedByteCompare 32 */ 33 34 package compiler.c2; 35 36 public class TestUnsignedByteCompare { 37 38 static int p, n; 39 report(byte[] ba, int i, boolean failed)40 static void report(byte[] ba, int i, boolean failed) { 41 // Enable for debugging: 42 // System.out.println((failed ? "Failed" : "Passed") + " with: " + ba[i] + " at " + i); 43 } 44 m1(byte[] ba)45 static void m1(byte[] ba) { 46 for (int i = 0; i < ba.length; i++) { 47 if ((ba[i] & 0xFF) < 0x10) { 48 p++; 49 report(ba, i, true); 50 } else { 51 n++; 52 report(ba, i, false); 53 } 54 } 55 } 56 m2(byte[] ba)57 static void m2(byte[] ba) { 58 for (int i = 0; i < ba.length; i++) { 59 if (((ba[i] & 0xFF) & 0x80) < 0) { 60 p++; 61 report(ba, i, true); 62 } else { 63 n++; 64 report(ba, i, false); 65 } 66 } 67 } 68 main(String[] args)69 static public void main(String[] args) { 70 final int tries = 1_000; 71 final int count = 1_000; 72 73 byte[] ba = new byte[count]; 74 75 for (int i = 0; i < count; i++) { 76 int v = -(i % 126 + 1); 77 ba[i] = (byte)v; 78 } 79 80 for (int t = 0; t < tries; t++) { 81 m1(ba); 82 if (p != 0) { 83 throw new IllegalStateException("m1 error: p = " + p + ", n = " + n); 84 } 85 } 86 87 for (int t = 0; t < tries; t++) { 88 m2(ba); 89 if (p != 0) { 90 throw new IllegalStateException("m2 error: p = " + p + ", n = " + n); 91 } 92 } 93 } 94 } 95