vendor/rand/benches/misc.rs

   1 // Copyright 2018 Developers of the Rand project.
   2 //
   3 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   4 // https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   5 // <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
   6 // option. This file may not be copied, modified, or distributed
   7 // except according to those terms.
   8
   9 #![feature(test)]
  10
  11 extern crate test;
  12
  13 const RAND_BENCH_N: u64 = 1000;
  14
  15 use test::Bencher;
  16
  17 use rand::distributions::{Bernoulli, Distribution, Standard};
  18 use rand::prelude::*;
  19 use rand_pcg::{Pcg32, Pcg64Mcg};
  20
  21 #[bench]
  22 fn misc_gen_bool_const(b: &mut Bencher) {
  23     let mut rng = Pcg32::from_rng(&mut thread_rng()).unwrap();
  24     b.iter(|| {
  25         let mut accum = true;
  26         for _ in 0..crate::RAND_BENCH_N {
  27             accum ^= rng.gen_bool(0.18);
  28         }
  29         accum
  30     })
  31 }
  32
  33 #[bench]
  34 fn misc_gen_bool_var(b: &mut Bencher) {
  35     let mut rng = Pcg32::from_rng(&mut thread_rng()).unwrap();
  36     b.iter(|| {
  37         let mut accum = true;
  38         let mut p = 0.18;
  39         for _ in 0..crate::RAND_BENCH_N {
  40             accum ^= rng.gen_bool(p);
  41             p += 0.0001;
  42         }
  43         accum
  44     })
  45 }
  46
  47 #[bench]
  48 fn misc_gen_ratio_const(b: &mut Bencher) {
  49     let mut rng = Pcg32::from_rng(&mut thread_rng()).unwrap();
  50     b.iter(|| {
  51         let mut accum = true;
  52         for _ in 0..crate::RAND_BENCH_N {
  53             accum ^= rng.gen_ratio(2, 3);
  54         }
  55         accum
  56     })
  57 }
  58
  59 #[bench]
  60 fn misc_gen_ratio_var(b: &mut Bencher) {
  61     let mut rng = Pcg32::from_rng(&mut thread_rng()).unwrap();
  62     b.iter(|| {
  63         let mut accum = true;
  64         for i in 2..(crate::RAND_BENCH_N as u32 + 2) {
  65             accum ^= rng.gen_ratio(i, i + 1);
  66         }
  67         accum
  68     })
  69 }
  70
  71 #[bench]
  72 fn misc_bernoulli_const(b: &mut Bencher) {
  73     let mut rng = Pcg32::from_rng(&mut thread_rng()).unwrap();
  74     b.iter(|| {
  75         let d = rand::distributions::Bernoulli::new(0.18).unwrap();
  76         let mut accum = true;
  77         for _ in 0..crate::RAND_BENCH_N {
  78             accum ^= rng.sample(d);
  79         }
  80         accum
  81     })
  82 }
  83
  84 #[bench]
  85 fn misc_bernoulli_var(b: &mut Bencher) {
  86     let mut rng = Pcg32::from_rng(&mut thread_rng()).unwrap();
  87     b.iter(|| {
  88         let mut accum = true;
  89         let mut p = 0.18;
  90         for _ in 0..crate::RAND_BENCH_N {
  91             let d = Bernoulli::new(p).unwrap();
  92             accum ^= rng.sample(d);
  93             p += 0.0001;
  94         }
  95         accum
  96     })
  97 }
  98
  99 #[bench]
 100 fn gen_1k_iter_repeat(b: &mut Bencher) {
 101     use std::iter;
 102     let mut rng = Pcg64Mcg::from_rng(&mut thread_rng()).unwrap();
 103     b.iter(|| {
 104         let v: Vec<u64> = iter::repeat(()).map(|()| rng.gen()).take(128).collect();
 105         v
 106     });
 107     b.bytes = 1024;
 108 }
 109
 110 #[bench]
 111 fn gen_1k_sample_iter(b: &mut Bencher) {
 112     let mut rng = Pcg64Mcg::from_rng(&mut thread_rng()).unwrap();
 113     b.iter(|| {
 114         let v: Vec<u64> = Standard.sample_iter(&mut rng).take(128).collect();
 115         v
 116     });
 117     b.bytes = 1024;
 118 }
 119
 120 #[bench]
 121 fn gen_1k_gen_array(b: &mut Bencher) {
 122     let mut rng = Pcg64Mcg::from_rng(&mut thread_rng()).unwrap();
 123     b.iter(|| {
 124         // max supported array length is 32!
 125         let v: [[u64; 32]; 4] = rng.gen();
 126         v
 127     });
 128     b.bytes = 1024;
 129 }
 130
 131 #[bench]
 132 fn gen_1k_fill(b: &mut Bencher) {
 133     let mut rng = Pcg64Mcg::from_rng(&mut thread_rng()).unwrap();
 134     let mut buf = [0u64; 128];
 135     b.iter(|| {
 136         rng.fill(&mut buf[..]);
 137         buf
 138     });
 139     b.bytes = 1024;
 140 }