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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 package org.openjdk.bench.java.lang.invoke;
  26 
  27 import org.openjdk.jmh.annotations.Benchmark;
  28 import org.openjdk.jmh.annotations.BenchmarkMode;
  29 import org.openjdk.jmh.annotations.Mode;
  30 import org.openjdk.jmh.annotations.OutputTimeUnit;
  31 import org.openjdk.jmh.annotations.Scope;
  32 import org.openjdk.jmh.annotations.Setup;
  33 import org.openjdk.jmh.annotations.State;
  34 
  35 import java.lang.invoke.MethodHandle;
  36 import java.lang.invoke.MethodHandles;
  37 import java.lang.invoke.MethodType;
  38 import java.lang.reflect.Method;
  39 import java.util.concurrent.TimeUnit;
  40 
  41 /**
  42  * Benchmark to assess basic MethodHandle performance.
  43  */
  44 @BenchmarkMode(Mode.AverageTime)
  45 @OutputTimeUnit(TimeUnit.NANOSECONDS)
  46 @State(Scope.Thread)
  47 public class MethodHandleBasicInvoke {
  48 
  49     /*
  50      * Implementation notes:
  51      *   - this is a very basic test, does not do any parameter conversion (in fact, no parameters at all)
  52      *   - baselines include calling method directly, and doing the same via reflection
  53      *   - baselineRaw is known to be super-fast with good inlining
  54      */
  55 
  56     private int i;
  57     private static MethodHandle mh;
  58     private static Method ref;
  59     private static MethodHandle mhUnreflect;
  60 
  61     @Setup
  62     public void setup() throws Throwable {
  63         mh = MethodHandles.lookup().findVirtual(MethodHandleBasicInvoke.class, "doWork", MethodType.methodType(int.class));
  64 
  65         ref = MethodHandleBasicInvoke.class.getMethod("doWork");
  66         ref.setAccessible(true);
  67 
  68         mhUnreflect = MethodHandles.lookup().unreflect(ref);
  69     }
  70 
  71     @Benchmark
  72     public int baselineRaw() throws Throwable {
  73         return doWork();
  74     }
  75 
  76     @Benchmark
  77     public int baselineReflect() throws Throwable {
  78         return (int) ref.invoke(this);
  79     }
  80 
  81     @Benchmark
  82     public int testMH_Plain_Invoke() throws Throwable {
  83         return (int) mh.invoke(this);
  84     }
  85 
  86     @Benchmark
  87     public int testMH_Plain_Exact() throws Throwable {
  88         return (int) mh.invokeExact(this);
  89     }
  90 
  91     @Benchmark
  92     public int testMH_Unreflect_Invoke() throws Throwable {
  93         return (int) mhUnreflect.invoke(this);
  94     }
  95 
  96     @Benchmark
  97     public int testMH_Unreflect_Exact() throws Throwable {
  98         return (int) mhUnreflect.invokeExact(this);
  99     }
 100 
 101     public int doWork() {
 102         return i++;
 103     }
 104 
 105 }