/* * Copyright 2015 SAP AG. 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 8080190 * @key regression * @summary Test that the rotate distance used in the rotate instruction is properly masked with 0x1f * @run main/othervm -Xbatch -XX:-UseOnStackReplacement IntRotateWithImmediate * @author volker.simonis@gmail.com */ public class IntRotateWithImmediate { // This is currently the same as Integer.rotateRight() static int rotateRight(int i, int distance) { // On some architectures (i.e. x86_64 and ppc64) the following computation is // matched in the .ad file into a single MachNode which emmits a single rotate // machine instruction. It is important that the shift amount is masked to match // corresponding immediate width in the native instruction. On x86_64 the rotate // left instruction ('rol') encodes an 8-bit immediate while the corresponding // 'rotlwi' instruction on Power only encodes a 5-bit immediate. return ((i >>> distance) | (i << -distance)); } static int compute(int x) { return rotateRight(x, 3); } public static void main(String args[]) { int val = 4096; int firstResult = compute(val); for (int i = 0; i < 100000; i++) { int newResult = compute(val); if (firstResult != newResult) { throw new InternalError(firstResult + " != " + newResult); } } System.out.println("OK"); } }