1/* 2 * Copyright (c) 2015 SAP SE. 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 * 32 * @run main/othervm -Xbatch -XX:-UseOnStackReplacement compiler.codegen.IntRotateWithImmediate 33 * @author volker.simonis@gmail.com 34 */ 35 36package compiler.codegen; 37 38public class IntRotateWithImmediate { 39 40 // This is currently the same as Integer.rotateRight() 41 static int rotateRight1(int i, int distance) { 42 // On some architectures (i.e. x86_64 and ppc64) the following computation is 43 // matched in the .ad file into a single MachNode which emmits a single rotate 44 // machine instruction. It is important that the shift amount is masked to match 45 // corresponding immediate width in the native instruction. On x86_64 the rotate 46 // left instruction ('rol') encodes an 8-bit immediate while the corresponding 47 // 'rotlwi' instruction on Power only encodes a 5-bit immediate. 48 return ((i >>> distance) | (i << -distance)); 49 } 50 51 static int rotateRight2(int i, int distance) { 52 return ((i >>> distance) | (i << (32 - distance))); 53 } 54 55 static int compute1(int x) { 56 return rotateRight1(x, 3); 57 } 58 59 static int compute2(int x) { 60 return rotateRight2(x, 3); 61 } 62 63 public static void main(String args[]) { 64 int val = 4096; 65 66 int firstResult = compute1(val); 67 68 for (int i = 0; i < 100000; i++) { 69 int newResult = compute1(val); 70 if (firstResult != newResult) { 71 throw new InternalError(firstResult + " != " + newResult); 72 } 73 newResult = compute2(val); 74 if (firstResult != newResult) { 75 throw new InternalError(firstResult + " != " + newResult); 76 } 77 } 78 System.out.println("OK"); 79 } 80 81} 82