1 /* 2 * Copyright (c) 2014 Oracle and/or its affiliates. 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 package org.openjdk.bench.java.lang.invoke; 24 25 import org.openjdk.jmh.annotations.Benchmark; 26 import org.openjdk.jmh.annotations.BenchmarkMode; 27 import org.openjdk.jmh.annotations.Mode; 28 import org.openjdk.jmh.annotations.OutputTimeUnit; 29 import org.openjdk.jmh.annotations.Scope; 30 import org.openjdk.jmh.annotations.Setup; 31 import org.openjdk.jmh.annotations.State; 32 33 import java.lang.invoke.MethodHandle; 34 import java.lang.invoke.MethodHandles; 35 import java.util.concurrent.TimeUnit; 36 37 /** 38 * Benchmark assesses the performance of MethodHandles.arrayElementGetter 39 * 40 * @author Aleksey Shipilev (aleksey.shipilev@oracle.com) 41 */ 42 @BenchmarkMode(Mode.AverageTime) 43 @OutputTimeUnit(TimeUnit.NANOSECONDS) 44 @State(Scope.Thread) 45 public class MethodHandlesArrayElementGetter { 46 47 /** 48 * Implementation notes: 49 * - creating simple array, and accessing the middle element 50 * - might have done iteration over array, but that will measure pipelining effects instead 51 * - volatile modifier on array breaks the DCE, which would otherwise eliminate the array load 52 * - the rationale for array size and access pattern is coherent to SetterBench 53 */ 54 55 private static final int SIZE = 1024; 56 private static final int POS = SIZE/2; 57 58 private static MethodHandle mh; 59 private volatile int[] array; 60 61 @Setup 62 public void setup() throws Throwable { 63 array = new int[SIZE]; 64 for (int i = 0; i < SIZE; i++) { 65 array[i] = i; 66 } 67 mh = MethodHandles.arrayElementGetter(int[].class); 68 } 69 70 @Benchmark 71 public MethodHandle testCreate() { 72 return MethodHandles.arrayElementGetter(int[].class); 73 } 74 75 @Benchmark 76 public int baselineRaw() { 77 return access(array, POS); 78 } 79 80 @Benchmark 81 public int testGetter() throws Throwable { 82 return (int) mh.invoke(array, POS); 83 } 84 85 public int access(int[] array, int pos) { 86 return array[pos]; 87 } 88 89 }