1 /* 2 * Copyright (C) 2010 Google Inc. 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package examples; 18 19 import com.google.caliper.Benchmark; 20 import com.google.caliper.Param; 21 22 /** 23 * Testing the old canard that looping backwards is faster. 24 */ 25 public class LoopingBackwardsBenchmark { 26 @Param({"2", "20", "2000", "20000000"}) int max; 27 forwards(int reps)28 @Benchmark int forwards(int reps) { 29 int dummy = 0; 30 for (int i = 0; i < reps; i++) { 31 for (int j = 0; j < max; j++) { 32 dummy += j; 33 } 34 } 35 return dummy; 36 } 37 backwards(int reps)38 @Benchmark int backwards(int reps) { 39 int dummy = 0; 40 for (int i = 0; i < reps; i++) { 41 for (int j = max - 1; j >= 0; j--) { 42 dummy += j; 43 } 44 } 45 return dummy; 46 } 47 } 48