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diff --git a/rand/rand_xoshiro/src/xoroshiro64star.rs b/rand/rand_xoshiro/src/xoroshiro64star.rs
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+// 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.
+
+use byteorder::{ByteOrder, LittleEndian};
+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)]
+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 {
+ let mut s = [0; 8];
+ LittleEndian::write_u64(&mut s, seed);
+ Xoroshiro64Star::from_seed(s)
+ }
+}
+
+#[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);
+ }
+ }
+}