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 import org.openjdk.jmh.annotations.Scope; 30 import org.openjdk.jmh.annotations.State; 31 32 import java.util.concurrent.TimeUnit; 33 34 /** 35 * Tests for removal of redundant stores. It's crucial for the tests to be valid that inlining and allocation is 36 * performed as described in this file. 37 */ 38 @BenchmarkMode(Mode.AverageTime) 39 @OutputTimeUnit(TimeUnit.NANOSECONDS) 40 @State(Scope.Thread) 41 public class StoreAfterStore { 42 public int s1 = 1, s2 = 2, s3 = 3, s4 = 4, s5 = 5, s6 = 6, s7 = 7, s8 = 8; 43 44 /** 45 * Test removal of redundant zero stores following an object allocation. 46 */ 47 @Benchmark 48 public AllocAndZeroStoreHelper testAllocAndZeroStore() throws Exception { 49 return new AllocAndZeroStoreHelper(s1, s2, s3, s4, s5, s6, s7, s8); 50 } 51 52 /** 53 * Test removal of stores followed by stores to the same memory location. 54 */ 55 @Benchmark 56 public StoreAndStoreHelper testStoreAndStore() throws Exception { 57 return new StoreAndStoreHelper(s1, s2, s3, s4, s5, s6, s7, s8); 58 } 59 60 61 /** 62 * Helper for alloc followed by zero store testing. 63 */ 64 static class AllocAndZeroStoreHelper { 65 public volatile int vf1, vf2, vf3, vf4, vf5, vf6, vf7, vf8; 66 67 public static int s1, s2, s3, s4, s5, s6, s7, s8; 68 69 private AllocAndZeroStoreHelper() { 70 this.vf1 = 0; 71 this.vf2 = 0; 72 this.vf3 = 0; 73 this.vf4 = 0; 74 this.vf5 = 0; 75 this.vf6 = 0; 76 this.vf7 = 0; 77 this.vf8 = 0; 78 } 79 80 private AllocAndZeroStoreHelper(int l1, int l2, int l3, int l4, int l5, int l6, int l7, int l8) { 81 this(); // Redundant initialization to zero here 82 83 // dummy stores 84 s1 = l1; 85 s2 = l2; 86 s3 = l3; 87 s4 = l4; 88 s5 = l5; 89 s6 = l6; 90 s7 = l7; 91 s8 = l8; 92 } 93 94 } 95 96 /** 97 * Helper for store made redundant by subsequent store testing. 98 */ 99 static class StoreAndStoreHelper { 100 public volatile int vf1, vf2, vf3, vf4, vf5, vf6, vf7, vf8; 101 102 private StoreAndStoreHelper() { 103 this.vf1 = -1; 104 this.vf2 = -1; 105 this.vf3 = -1; 106 this.vf4 = -1; 107 this.vf5 = -1; 108 this.vf6 = -1; 109 this.vf7 = -1; 110 this.vf8 = -1; 111 } 112 113 private StoreAndStoreHelper(int l1, int l2, int l3, int l4, int l5, int l6, int l7, int l8) { 114 this(); // Initialize all to -1 here, redundant wrt to the below stores 115 116 this.vf1 = l1; 117 this.vf2 = l2; 118 this.vf3 = l3; 119 this.vf4 = l4; 120 this.vf5 = l5; 121 this.vf6 = l6; 122 this.vf7 = l7; 123 this.vf8 = l8; 124 } 125 126 } 127 }