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.lang.invoke.MethodType;
  36 import java.util.concurrent.TimeUnit;
  37 
  38 /**
  39  * Benchmark assesses currying with MethodHandle.bindTo() performance
  40  */
  41 @BenchmarkMode(Mode.AverageTime)
  42 @OutputTimeUnit(TimeUnit.NANOSECONDS)
  43 @State(Scope.Thread)
  44 public class MethodHandleBindToCurry {
  45 
  46     /*
  47        Implementation notes:
  48           - calls static method to avoid binding "this"
  49           - tests the performance of gradually curried methods, hoping for compiler to optimize
  50           - arguments are volatile, to break optimistic CSE happening before the actual call
  51           - using invokeExact and Integers to skip argument conversions
  52           - baseline includes calling the method directly, and this is known to be super-fast due to inlining
  53      */
  54 
  55     private MethodHandle mhOrig;
  56     private MethodHandle mhCurry1;
  57     private MethodHandle mhCurry2;
  58     private MethodHandle mhCurry3;
  59 
  60     private volatile Integer arg1 = 1;
  61     private volatile Integer arg2 = 2;
  62     private volatile Integer arg3 = 3;
  63 
  64     @Setup
  65     public void setup() throws Throwable {
  66         mhOrig = MethodHandles.lookup().findStatic(MethodHandleBindToCurry.class, "doWork",
  67                 MethodType.methodType(int.class, Integer.class, Integer.class, Integer.class));
  68         mhCurry1 = mhOrig.bindTo(arg1);
  69         mhCurry2 = mhCurry1.bindTo(arg2);
  70         mhCurry3 = mhCurry2.bindTo(arg3);
  71     }
  72 
  73     @Benchmark
  74     public int baselineRaw() {
  75         return doWork(arg1, arg2, arg3);
  76     }
  77 
  78     @Benchmark
  79     public int testInvoke_C0() throws Throwable {
  80         return (int) mhOrig.invokeExact(arg1, arg2, arg3);
  81     }
  82 
  83     @Benchmark
  84     public int testInvoke_C1() throws Throwable {
  85         return (int) mhCurry1.invokeExact(arg2, arg3);
  86     }
  87 
  88     @Benchmark
  89     public int testInvoke_C2() throws Throwable {
  90         return (int) mhCurry2.invokeExact(arg3);
  91     }
  92 
  93     @Benchmark
  94     public int testInvoke_C3() throws Throwable {
  95         return (int) mhCurry3.invokeExact();
  96     }
  97 
  98     public static int doWork(Integer a, Integer b, Integer c) {
  99         return 31*(31*(31*a + b) + c);
 100     }
 101 
 102 }