| /* |
| * Copyright (c) 2018, Red Hat, Inc. 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 8214344 |
| * @summary LoadVector from a known element of a stable array shouldn't attempt to constant fold |
| * @modules java.base/jdk.internal.vm.annotation |
| * |
| * @run main/bootclasspath/othervm -XX:-TieredCompilation -XX:-BackgroundCompilation -XX:-UseOnStackReplacement LoadVectorFromStableArray |
| * |
| */ |
| |
| import jdk.internal.vm.annotation.Stable; |
| |
| public class LoadVectorFromStableArray { |
| public static void main(String[] args) { |
| byte[] byte_array = new byte[100]; |
| for (int i = 0; i < 20_000; i++) { |
| test_helper(0, 0); |
| test_helper(42, 0); |
| test_helper2(0, 20, byte_array, byte_array); |
| } |
| for (int i = 0; i < 20_000; i++) { |
| test(20, true); |
| test(20, false); |
| } |
| } |
| |
| static @Stable byte[] stable_array1 = new byte[100]; |
| static @Stable byte[] stable_array2 = new byte[100]; |
| |
| private static void test(int stop, boolean flag) { |
| int start = 0; |
| byte[] byte_array1 = stable_array1; |
| byte[] byte_array2 = flag ? stable_array1 : stable_array2; |
| int k = 2; |
| for (; k < 4; k *= 2); |
| int i = test_helper(k, stop); |
| // Loop in this method is unrolled and vectorized, then, upper |
| // bound is found to be constant and small. A single iteration |
| // of the main loop is executed. That iteration attempts to |
| // load a vector element from the array at a constant offset. |
| test_helper2(start, i, byte_array1, byte_array2); |
| } |
| |
| |
| private static void test_helper2(int start, int stop, byte[] byte_array1, byte[] byte_array2) { |
| for (int j = start; j < stop; j++) { |
| byte b = byte_array1[j+3]; |
| byte_array2[j+3] = b; |
| } |
| } |
| |
| private static int test_helper(int k, int stop) { |
| int i = 0; |
| if (k == 42) { |
| i = stop; |
| } else { |
| i = 5; |
| } |
| return i; |
| } |
| } |