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.vm.compiler; 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 30 import java.util.concurrent.TimeUnit; 31 32 /** 33 * Tests how well the JVM can remove stores after allocation of objects. 34 */ 35 @BenchmarkMode(Mode.AverageTime) 36 @OutputTimeUnit(TimeUnit.NANOSECONDS) 37 public class PostAllocationStores { 38 39 /** Tests allocation with explicit stores of null/zero to all fields. */ 40 @Benchmark 41 public Object testAllocationWithNullStores() throws Exception { 42 return new TestWithNullStores(); 43 } 44 45 /** 46 * Tests allocation with explicit stores of non-null/non-zero to all fields. This test exists as a complement to the 47 * one above. 48 */ 49 @Benchmark 50 public Object testAllocationWithNonNullStores() throws Exception { 51 return new TestWithNonNullStores(); 52 } 53 54 /** Tests allocation with explicit stores of null/zero to all fields, where all fields are volatile. */ 55 @Benchmark 56 public Object testAllocationWithNullVolatileStores() throws Exception { 57 return new TestWithNullVolatileStores(); 58 } 59 60 /** Tests allocation without any explicit stores to any fields. */ 61 @Benchmark 62 public Object testAllocationWithoutStores() throws Exception { 63 return new TestWithoutStores(); 64 } 65 66 static class TestWithNullStores { 67 Object objectField1; 68 Object objectField2; 69 Object objectField3; 70 int intField1; 71 int intField2; 72 long longField1; 73 74 public TestWithNullStores() { 75 objectField1 = null; 76 objectField2 = null; 77 objectField3 = null; 78 intField1 = 0; 79 intField2 = 0; 80 longField1 = 0L; 81 } 82 } 83 84 static class TestWithNonNullStores { 85 Object objectField1; 86 Object objectField2; 87 Object objectField3; 88 int intField1; 89 int intField2; 90 long longField1; 91 92 public TestWithNonNullStores() { 93 objectField1 = this; 94 objectField2 = this; 95 objectField3 = this; 96 intField1 = 4; 97 intField2 = 7; 98 longField1 = 2L; 99 } 100 } 101 102 static class TestWithNullVolatileStores { 103 volatile Object objectField1; 104 volatile Object objectField2; 105 volatile Object objectField3; 106 volatile int intField1; 107 volatile int intField2; 108 volatile long longField1; 109 110 public TestWithNullVolatileStores() { 111 objectField1 = null; 112 objectField2 = null; 113 objectField3 = null; 114 intField1 = 0; 115 intField2 = 0; 116 longField1 = 0L; 117 } 118 } 119 120 static class TestWithoutStores { 121 Object objectField1; 122 Object objectField2; 123 Object objectField3; 124 int intField1; 125 int intField2; 126 long longField1; 127 } 128 129 }