1 /* 2 * Copyright (C) 2011 The Guava Authors 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 com.google.common.math; 18 19 import static com.google.common.math.MathBenchmarking.ARRAY_MASK; 20 import static com.google.common.math.MathBenchmarking.ARRAY_SIZE; 21 import static com.google.common.math.MathBenchmarking.RANDOM_SOURCE; 22 import static com.google.common.math.MathBenchmarking.randomExponent; 23 import static com.google.common.math.MathBenchmarking.randomNonNegativeBigInteger; 24 import static com.google.common.math.MathBenchmarking.randomPositiveBigInteger; 25 26 import com.google.caliper.BeforeExperiment; 27 import com.google.caliper.Benchmark; 28 import com.google.common.math.LongMath; 29 30 /** 31 * Benchmarks for the non-rounding methods of {@code LongMath}. 32 * 33 * @author Louis Wasserman 34 */ 35 public class LongMathBenchmark { 36 private static final int[] exponents = new int[ARRAY_SIZE]; 37 private static final int[] factorialArguments = new int[ARRAY_SIZE]; 38 private static final int[][] binomialArguments = new int[ARRAY_SIZE][2]; 39 private static final long[] positive = new long[ARRAY_SIZE]; 40 private static final long[] nonnegative = new long[ARRAY_SIZE]; 41 private static final long[] longs = new long[ARRAY_SIZE]; 42 43 @BeforeExperiment 44 void setUp() { 45 for (int i = 0; i < ARRAY_SIZE; i++) { 46 exponents[i] = randomExponent(); 47 positive[i] = randomPositiveBigInteger(Long.SIZE - 1).longValue(); 48 nonnegative[i] = randomNonNegativeBigInteger(Long.SIZE - 1).longValue(); 49 longs[i] = RANDOM_SOURCE.nextLong(); 50 factorialArguments[i] = RANDOM_SOURCE.nextInt(30); 51 binomialArguments[i][1] = RANDOM_SOURCE.nextInt(MathBenchmarking.biggestBinomials.length); 52 int k = binomialArguments[i][1]; 53 binomialArguments[i][0] = 54 RANDOM_SOURCE.nextInt(MathBenchmarking.biggestBinomials[k] - k) + k; 55 } 56 } 57 58 @Benchmark int pow(int reps) { 59 int tmp = 0; 60 for (int i = 0; i < reps; i++) { 61 int j = i & ARRAY_MASK; 62 tmp += LongMath.pow(positive[j], exponents[j]); 63 } 64 return tmp; 65 } 66 67 @Benchmark int mod(int reps) { 68 int tmp = 0; 69 for (int i = 0; i < reps; i++) { 70 int j = i & ARRAY_MASK; 71 tmp += LongMath.mod(longs[j], positive[j]); 72 } 73 return tmp; 74 } 75 76 @Benchmark int gCD(int reps) { 77 int tmp = 0; 78 for (int i = 0; i < reps; i++) { 79 int j = i & ARRAY_MASK; 80 tmp += LongMath.mod(nonnegative[j], positive[j]); 81 } 82 return tmp; 83 } 84 85 @Benchmark int factorial(int reps) { 86 int tmp = 0; 87 for (int i = 0; i < reps; i++) { 88 int j = i & ARRAY_MASK; 89 tmp += LongMath.factorial(factorialArguments[j]); 90 } 91 return tmp; 92 } 93 94 @Benchmark int binomial(int reps) { 95 int tmp = 0; 96 for (int i = 0; i < reps; i++) { 97 int j = i & ARRAY_MASK; 98 tmp += LongMath.binomial(binomialArguments[j][0], binomialArguments[j][1]); 99 } 100 return tmp; 101 } 102 } 103
