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-rw-r--r--rand/rand_xoshiro/src/xoroshiro64star.rs102
1 files changed, 0 insertions, 102 deletions
diff --git a/rand/rand_xoshiro/src/xoroshiro64star.rs b/rand/rand_xoshiro/src/xoroshiro64star.rs
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--- a/rand/rand_xoshiro/src/xoroshiro64star.rs
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@@ -1,102 +0,0 @@
-// Copyright 2018 Developers of the Rand project.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#[cfg(feature="serde1")] use serde::{Serialize, Deserialize};
-use rand_core;
-use rand_core::le::read_u32_into;
-use rand_core::impls::{fill_bytes_via_next, next_u64_via_u32};
-use rand_core::{RngCore, SeedableRng};
-
-/// A xoroshiro64* random number generator.
-///
-/// The xoroshiro64* algorithm is not suitable for cryptographic purposes, but
-/// is very fast and has good statistical properties, besides a low linear
-/// complexity in the lowest bits.
-///
-/// The algorithm used here is translated from [the `xoroshiro64star.c`
-/// reference source code](http://xoshiro.di.unimi.it/xoroshiro64star.c) by
-/// David Blackman and Sebastiano Vigna.
-#[allow(missing_copy_implementations)]
-#[derive(Debug, Clone)]
-#[cfg_attr(feature="serde1", derive(Serialize, Deserialize))]
-pub struct Xoroshiro64Star {
- s0: u32,
- s1: u32,
-}
-
-impl RngCore for Xoroshiro64Star {
- #[inline]
- fn next_u32(&mut self) -> u32 {
- let r = self.s0.wrapping_mul(0x9E3779BB);
- impl_xoroshiro_u32!(self);
- r
- }
-
- #[inline]
- fn next_u64(&mut self) -> u64 {
- next_u64_via_u32(self)
- }
-
- #[inline]
- fn fill_bytes(&mut self, dest: &mut [u8]) {
- fill_bytes_via_next(self, dest);
- }
-
- #[inline]
- fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), rand_core::Error> {
- self.fill_bytes(dest);
- Ok(())
- }
-}
-
-impl SeedableRng for Xoroshiro64Star {
- type Seed = [u8; 8];
-
- /// Create a new `Xoroshiro64Star`. If `seed` is entirely 0, it will be
- /// mapped to a different seed.
- fn from_seed(seed: [u8; 8]) -> Xoroshiro64Star {
- deal_with_zero_seed!(seed, Self);
- let mut s = [0; 2];
- read_u32_into(&seed, &mut s);
-
- Xoroshiro64Star {
- s0: s[0],
- s1: s[1],
- }
- }
-
- /// Seed a `Xoroshiro64Star` from a `u64` using `SplitMix64`.
- fn seed_from_u64(seed: u64) -> Xoroshiro64Star {
- from_splitmix!(seed)
- }
-}
-
-#[cfg(test)]
-mod tests {
- use super::*;
-
- #[test]
- fn reference() {
- let mut rng = Xoroshiro64Star::from_seed([1, 0, 0, 0, 2, 0, 0, 0]);
- // These values were produced with the reference implementation:
- // http://xoshiro.di.unimi.it/xoshiro64star.c
- let expected = [
- 2654435771, 327208753, 4063491769, 4259754937, 261922412, 168123673,
- 552743735, 1672597395, 1031040050, 2755315674,
- ];
- for &e in &expected {
- assert_eq!(rng.next_u32(), e);
- }
- }
-
- #[test]
- fn zero_seed() {
- let mut rng = Xoroshiro64Star::seed_from_u64(0);
- assert_ne!(rng.next_u64(), 0);
- }
-}