1 /*
   2  * Copyright (c) 2015, 2015, 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 micro.benchmarks;
  24 
  25 import org.openjdk.jmh.annotations.Benchmark;
  26 import org.openjdk.jmh.annotations.Level;
  27 import org.openjdk.jmh.annotations.Scope;
  28 import org.openjdk.jmh.annotations.Setup;
  29 import org.openjdk.jmh.annotations.State;
  30 import org.openjdk.jmh.annotations.Warmup;
  31 
  32 /**
  33  * Benchmarks cost of guarded intrinsics at indirect call sites.
  34  */
  35 public class GuardedIntrinsicBenchmark extends BenchmarkBase {
  36 
  37     public static class HashcodeState {
  38         public Object val1;
  39         public Object val2;
  40 
  41         public HashcodeState(Object val1, Object val2) {
  42             this.val1 = val1;
  43             this.val2 = val2;
  44         }
  45 
  46         int getNextHashCode() {
  47             return val1.hashCode();
  48         }
  49 
  50         protected void swap() {
  51             Object tmp = val1;
  52             val1 = val2;
  53             val2 = tmp;
  54         }
  55     }
  56 
  57     /**
  58      * Objects that all override {@link Object#hashCode()}. The objects used have hashCode
  59      * implementations that are basically getters as we want to measure the overhead of hashCode
  60      * dispatch, not the cost of the hashCode implementation.
  61      */
  62     @State(Scope.Benchmark)
  63     public static class OverrideHashcode extends HashcodeState {
  64         public OverrideHashcode() {
  65             super(Short.valueOf((short) 100), Integer.valueOf(42));
  66         }
  67 
  68         @Setup(Level.Invocation)
  69         public void beforeInvocation() {
  70             swap();
  71         }
  72     }
  73 
  74     @Benchmark
  75     @Warmup(iterations = 10)
  76     public int overrideHashCode(OverrideHashcode state) {
  77         return state.getNextHashCode();
  78     }
  79 
  80     /**
  81      * Objects that do not override {@link Object#hashCode()}.
  82      */
  83     @State(Scope.Benchmark)
  84     public static class InheritHashcode extends HashcodeState {
  85         public InheritHashcode() {
  86             super(Class.class, Runtime.getRuntime());
  87         }
  88 
  89         @Setup(Level.Invocation)
  90         public void beforeInvocation() {
  91             swap();
  92         }
  93     }
  94 
  95     @Benchmark
  96     @Warmup(iterations = 10)
  97     public int inheritHashCode(InheritHashcode state) {
  98         return state.getNextHashCode();
  99     }
 100 
 101     /**
 102      * Some objects that override {@link Object#hashCode()} and some that don't.
 103      */
 104     @State(Scope.Benchmark)
 105     public static class MixedHashcode extends HashcodeState {
 106         public MixedHashcode() {
 107             super(Short.valueOf((short) 100), Runtime.getRuntime());
 108         }
 109 
 110         @Setup(Level.Invocation)
 111         public void beforeInvocation() {
 112             swap();
 113         }
 114     }
 115 
 116     @Benchmark
 117     @Warmup(iterations = 10)
 118     public int mixedHashCode(MixedHashcode state) {
 119         return state.getNextHashCode();
 120     }
 121 }