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.randomNonZeroBigInteger;
23 import static com.google.common.math.MathBenchmarking.randomPositiveBigInteger;
24 
25 import com.google.caliper.BeforeExperiment;
26 import com.google.caliper.Benchmark;
27 import com.google.caliper.Param;
28 import java.math.RoundingMode;
29 
30 /**
31  * Benchmarks for the rounding methods of {@code LongMath}.
32  *
33  * @author Louis Wasserman
34  */
35 public class LongMathRoundingBenchmark {
36   @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
37   RoundingMode mode;
38 
39   private static final long[] positive = new long[ARRAY_SIZE];
40   private static final long[] nonzero = new long[ARRAY_SIZE];
41   private static final long[] longs = new long[ARRAY_SIZE];
42 
43   @BeforeExperiment
setUp()44   void setUp() {
45     for (int i = 0; i < ARRAY_SIZE; i++) {
46       positive[i] = randomPositiveBigInteger(Long.SIZE - 2).longValue();
47       nonzero[i] = randomNonZeroBigInteger(Long.SIZE - 2).longValue();
48       longs[i] = RANDOM_SOURCE.nextLong();
49     }
50   }
51 
52   @Benchmark
log2(int reps)53   int log2(int reps) {
54     int tmp = 0;
55     for (int i = 0; i < reps; i++) {
56       int j = i & ARRAY_MASK;
57       tmp += LongMath.log2(positive[j], mode);
58     }
59     return tmp;
60   }
61 
62   @Benchmark
log10(int reps)63   int log10(int reps) {
64     int tmp = 0;
65     for (int i = 0; i < reps; i++) {
66       int j = i & ARRAY_MASK;
67       tmp += LongMath.log10(positive[j], mode);
68     }
69     return tmp;
70   }
71 
72   @Benchmark
sqrt(int reps)73   int sqrt(int reps) {
74     int tmp = 0;
75     for (int i = 0; i < reps; i++) {
76       int j = i & ARRAY_MASK;
77       tmp += LongMath.sqrt(positive[j], mode);
78     }
79     return tmp;
80   }
81 
82   @Benchmark
divide(int reps)83   int divide(int reps) {
84     int tmp = 0;
85     for (int i = 0; i < reps; i++) {
86       int j = i & ARRAY_MASK;
87       tmp += LongMath.divide(longs[j], nonzero[j], mode);
88     }
89     return tmp;
90   }
91 }
92