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.util.concurrent.TimeUnit;
  39 
  40 /**
  41  * Benchmark assesses currying with MethodHandle.bindTo() performance
  42  */
  43 @BenchmarkMode(Mode.AverageTime)
  44 @OutputTimeUnit(TimeUnit.NANOSECONDS)
  45 @State(Scope.Thread)
  46 public class MethodHandleBindToCurry {
  47 
  48     /*
  49        Implementation notes:
  50           - calls static method to avoid binding "this"
  51           - tests the performance of gradually curried methods, hoping for compiler to optimize
  52           - arguments are volatile, to break optimistic CSE happening before the actual call
  53           - using invokeExact and Integers to skip argument conversions
  54           - baseline includes calling the method directly, and this is known to be super-fast due to inlining
  55      */
  56 
  57     private MethodHandle mhOrig;
  58     private MethodHandle mhCurry1;
  59     private MethodHandle mhCurry2;
  60     private MethodHandle mhCurry3;
  61 
  62     private volatile Integer arg1 = 1;
  63     private volatile Integer arg2 = 2;
  64     private volatile Integer arg3 = 3;
  65 
  66     @Setup
  67     public void setup() throws Throwable {
  68         mhOrig = MethodHandles.lookup().findStatic(MethodHandleBindToCurry.class, "doWork",
  69                 MethodType.methodType(int.class, Integer.class, Integer.class, Integer.class));
  70         mhCurry1 = mhOrig.bindTo(arg1);
  71         mhCurry2 = mhCurry1.bindTo(arg2);
  72         mhCurry3 = mhCurry2.bindTo(arg3);
  73     }
  74 
  75     @Benchmark
  76     public int baselineRaw() {
  77         return doWork(arg1, arg2, arg3);
  78     }
  79 
  80     @Benchmark
  81     public int testInvoke_C0() throws Throwable {
  82         return (int) mhOrig.invokeExact(arg1, arg2, arg3);
  83     }
  84 
  85     @Benchmark
  86     public int testInvoke_C1() throws Throwable {
  87         return (int) mhCurry1.invokeExact(arg2, arg3);
  88     }
  89 
  90     @Benchmark
  91     public int testInvoke_C2() throws Throwable {
  92         return (int) mhCurry2.invokeExact(arg3);
  93     }
  94 
  95     @Benchmark
  96     public int testInvoke_C3() throws Throwable {
  97         return (int) mhCurry3.invokeExact();
  98     }
  99 
 100     public static int doWork(Integer a, Integer b, Integer c) {
 101         return 31*(31*(31*a + b) + c);
 102     }
 103 
 104 }