1 /* 2 * Copyright 2015 SAP AG. All Rights Reserved. 3 * Copyright (c) 2016, Red Hat, Inc. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. 9 * 10 * This code is distributed in the hope that it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 * version 2 for more details (a copy is included in the LICENSE file that 14 * accompanied this code). 15 * 16 * You should have received a copy of the GNU General Public License version 17 * 2 along with this work; if not, write to the Free Software Foundation, 18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 19 * 20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 21 * or visit www.oracle.com if you need additional information or have any 22 * questions. 23 */ 24 25 /* 26 * @test 27 * @bug 8080190 28 * @bug 8154537 29 * @key regression 30 * @summary Test that the rotate distance used in the rotate instruction is properly masked with 0x1f 31 * @run main/othervm -Xbatch -XX:-UseOnStackReplacement IntRotateWithImmediate 32 * @author volker.simonis@gmail.com 33 */ 34 35 public class IntRotateWithImmediate { 36 37 // This is currently the same as Integer.rotateRight() 38 static int rotateRight1(int i, int distance) { 39 // On some architectures (i.e. x86_64 and ppc64) the following computation is 40 // matched in the .ad file into a single MachNode which emmits a single rotate 41 // machine instruction. It is important that the shift amount is masked to match 42 // corresponding immediate width in the native instruction. On x86_64 the rotate 43 // left instruction ('rol') encodes an 8-bit immediate while the corresponding 44 // 'rotlwi' instruction on Power only encodes a 5-bit immediate. 45 return ((i >>> distance) | (i << -distance)); 46 } 47 48 static int rotateRight2(int i, int distance) { 49 return ((i >>> distance) | (i << (32-distance))); 50 } 51 52 static int compute1(int x) { 53 return rotateRight1(x, 3); 54 } 55 56 static int compute2(int x) { 57 return rotateRight2(x, 3); 58 } 59 60 public static void main(String args[]) { 61 int val = 4096; 62 63 int firstResult = compute1(val); 64 65 for (int i = 0; i < 100000; i++) { 66 int newResult = compute1(val); 67 if (firstResult != newResult) { 68 throw new InternalError(firstResult + " != " + newResult); 69 } 70 newResult = compute2(val); 71 if (firstResult != newResult) { 72 throw new InternalError(firstResult + " != " + newResult); 73 } 74 } 75 System.out.println("OK"); 76 } 77 78 }