diff options
Diffstat (limited to 'rand/rand_pcg')
| -rw-r--r-- | rand/rand_pcg/CHANGELOG.md | 14 | ||||
| -rw-r--r-- | rand/rand_pcg/COPYRIGHT | 12 | ||||
| -rw-r--r-- | rand/rand_pcg/Cargo.toml | 37 | ||||
| -rw-r--r-- | rand/rand_pcg/LICENSE-APACHE | 201 | ||||
| -rw-r--r-- | rand/rand_pcg/LICENSE-MIT | 26 | ||||
| -rw-r--r-- | rand/rand_pcg/README.md | 51 | ||||
| -rw-r--r-- | rand/rand_pcg/build.rs | 8 | ||||
| -rw-r--r-- | rand/rand_pcg/src/lib.rs | 48 | ||||
| -rw-r--r-- | rand/rand_pcg/src/pcg128.rs | 122 | ||||
| -rw-r--r-- | rand/rand_pcg/src/pcg64.rs | 141 | ||||
| -rw-r--r-- | rand/rand_pcg/tests/lcg64xsh32.rs | 58 | ||||
| -rw-r--r-- | rand/rand_pcg/tests/mcg128xsl64.rs | 59 |
12 files changed, 777 insertions, 0 deletions
diff --git a/rand/rand_pcg/CHANGELOG.md b/rand/rand_pcg/CHANGELOG.md new file mode 100644 index 0000000..d37408d --- /dev/null +++ b/rand/rand_pcg/CHANGELOG.md @@ -0,0 +1,14 @@ +# Changelog +All notable changes to this project will be documented in this file. + +The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/) +and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html). + +## [0.1.1] - 2018-10-04 +- make `bincode` an explicit dependency when using Serde + +## [0.1.0] - 2018-10-04 +Initial release, including: + +- `Lcg64Xsh32` aka `Pcg32` +- `Mcg128Xsl64` aka `Pcg64Mcg` diff --git a/rand/rand_pcg/COPYRIGHT b/rand/rand_pcg/COPYRIGHT new file mode 100644 index 0000000..468d907 --- /dev/null +++ b/rand/rand_pcg/COPYRIGHT @@ -0,0 +1,12 @@ +Copyrights in the Rand project are retained by their contributors. No +copyright assignment is required to contribute to the Rand project. + +For full authorship information, see the version control history. + +Except as otherwise noted (below and/or in individual files), Rand is +licensed under the Apache License, Version 2.0 <LICENSE-APACHE> or +<http://www.apache.org/licenses/LICENSE-2.0> or the MIT license +<LICENSE-MIT> or <http://opensource.org/licenses/MIT>, at your option. + +The Rand project includes code from the Rust project +published under these same licenses. diff --git a/rand/rand_pcg/Cargo.toml b/rand/rand_pcg/Cargo.toml new file mode 100644 index 0000000..c8a29fc --- /dev/null +++ b/rand/rand_pcg/Cargo.toml @@ -0,0 +1,37 @@ +[package] +name = "rand_pcg" +version = "0.1.1" +authors = ["The Rand Project Developers"] +license = "MIT/Apache-2.0" +readme = "README.md" +repository = "https://github.com/rust-random/rand" +documentation = "https://rust-random.github.io/rand/rand_pcg" +homepage = "https://crates.io/crates/rand_pcg" +description = """ +Selected PCG random number generators +""" +keywords = ["random", "rng", "pcg"] +categories = ["algorithms", "no-std"] +build = "build.rs" + +[badges] +travis-ci = { repository = "rust-random/rand" } +appveyor = { repository = "rust-random/rand" } + +[features] +serde1 = ["serde", "serde_derive"] + +[dependencies] +rand_core = { path = "../rand_core", version = "0.3", default-features=false } +serde = { version = "1", optional = true } +serde_derive = { version = "^1.0.38", optional = true } + +[dev-dependencies] +# This is for testing serde, unfortunately we can't specify feature-gated dev +# deps yet, see: https://github.com/rust-lang/cargo/issues/1596 +# TODO: we shouldn't have to depend on i128 directly; it breaks tests on old +# compilers. `bincode` should automatically support this. +bincode = { version = "1", features = ["i128"] } + +[build-dependencies] +rustc_version = "0.2" diff --git a/rand/rand_pcg/LICENSE-APACHE b/rand/rand_pcg/LICENSE-APACHE new file mode 100644 index 0000000..17d7468 --- /dev/null +++ b/rand/rand_pcg/LICENSE-APACHE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + https://www.apache.org/licenses/ + +TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + +1. 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IN NO EVENT +SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY +CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR +IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER +DEALINGS IN THE SOFTWARE. diff --git a/rand/rand_pcg/README.md b/rand/rand_pcg/README.md new file mode 100644 index 0000000..4599813 --- /dev/null +++ b/rand/rand_pcg/README.md @@ -0,0 +1,51 @@ +# rand_pcg + +[](https://travis-ci.org/rust-random/rand) +[](https://ci.appveyor.com/project/rust-random/rand) +[](https://crates.io/crates/rand_pcg) +[[](https://rust-random.github.io/book/) +[](https://rust-random.github.io/rand/rand_pcg) +[](https://docs.rs/rand_pcg) +[](https://github.com/rust-random/rand#rust-version-requirements) + +Implements a selection of PCG random number generators. + +> PCG is a family of simple fast space-efficient statistically good algorithms +> for random number generation. [Melissa O'Neill, Harvey Mudd College, 2014]. + +The PCG algorithms are not suitable for cryptographic uses, but perform well +in statistical tests, use little memory and are fairly fast. +See the [pcg-random website](http://www.pcg-random.org/). + +This crate depends on [rand_core](https://crates.io/crates/rand_core) and is +part of the [Rand project](https://github.com/rust-random/rand). + +Links: + +- [API documentation (master)](https://rust-random.github.io/rand/rand_pcg) +- [API documentation (docs.rs)](https://docs.rs/rand_pcg) +- [Changelog](CHANGELOG.md) + + +## Crate Features + +`rand_pcg` is `no_std` compatible. It does not require any functionality +outside of the `core` lib, thus there are no features to configure. + +The `serde1` feature includes implementations of `Serialize` and `Deserialize` +for the included RNGs. NOTE: to use binary serialisation with any of the 64-bit +output (128-bit internal) RNGs, you must add the following dependency, since the +`i128` feature is not current enabled by default (this should be fixed soon): + +``` +bincode = { version = "1", features = ["i128"] } +``` + + +## License + +`rand_pcg` is distributed under the terms of both the MIT license and the +Apache License (Version 2.0). + +See [LICENSE-APACHE](LICENSE-APACHE) and [LICENSE-MIT](LICENSE-MIT), and +[COPYRIGHT](COPYRIGHT) for details. diff --git a/rand/rand_pcg/build.rs b/rand/rand_pcg/build.rs new file mode 100644 index 0000000..cb3ae20 --- /dev/null +++ b/rand/rand_pcg/build.rs @@ -0,0 +1,8 @@ +extern crate rustc_version; +use rustc_version::{version, Version}; + +fn main() { + if version().unwrap() >= Version::parse("1.26.0").unwrap() { + println!("cargo:rustc-cfg=rust_1_26"); + } +} diff --git a/rand/rand_pcg/src/lib.rs b/rand/rand_pcg/src/lib.rs new file mode 100644 index 0000000..5160e87 --- /dev/null +++ b/rand/rand_pcg/src/lib.rs @@ -0,0 +1,48 @@ +// 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. + +//! The PCG random number generators. +//! +//! This is a native Rust implementation of a small selection of PCG generators. +//! The primary goal of this crate is simple, minimal, well-tested code; in +//! other words it is explicitly not a goal to re-implement all of PCG. +//! +//! This crate provides: +//! +//! - `Pcg32` aka `Lcg64Xsh32`, officially known as `pcg32`, a general +//! purpose RNG. This is a good choice on both 32-bit and 64-bit CPUs +//! (for 32-bit output). +//! - `Pcg64Mcg` aka `Mcg128Xsl64`, officially known as `mcg_xsl_rr_128_64`, +//! a general purpose RNG using 128-bit multiplications. This has poor +//! performance on 32-bit CPUs but is a good choice on 64-bit CPUs for +//! both 32-bit and 64-bit output. (Note: this RNG is only available using +//! Rust 1.26 or later.) +//! +//! Both of these use 16 bytes of state and 128-bit seeds, and are considered +//! value-stable (i.e. any change affecting the output given a fixed seed would +//! be considered a breaking change to the crate). + +#![doc(html_logo_url = "https://www.rust-lang.org/logos/rust-logo-128x128-blk.png", + html_favicon_url = "https://www.rust-lang.org/favicon.ico", + html_root_url = "https://rust-random.github.io/rand/")] + +#![deny(missing_docs)] +#![deny(missing_debug_implementations)] + +#![no_std] + +extern crate rand_core; + +#[cfg(feature="serde1")] extern crate serde; +#[cfg(feature="serde1")] #[macro_use] extern crate serde_derive; + +mod pcg64; +#[cfg(rust_1_26)] mod pcg128; + +pub use self::pcg64::{Pcg32, Lcg64Xsh32}; +#[cfg(rust_1_26)] pub use self::pcg128::{Pcg64Mcg, Mcg128Xsl64}; diff --git a/rand/rand_pcg/src/pcg128.rs b/rand/rand_pcg/src/pcg128.rs new file mode 100644 index 0000000..9aff506 --- /dev/null +++ b/rand/rand_pcg/src/pcg128.rs @@ -0,0 +1,122 @@ +// Copyright 2018 Developers of the Rand project. +// Copyright 2017 Paul Dicker. +// Copyright 2014-2017 Melissa O'Neill and PCG Project contributors +// +// 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. + +//! PCG random number generators + +// This is the default multiplier used by PCG for 64-bit state. +const MULTIPLIER: u128 = 0x2360_ED05_1FC6_5DA4_4385_DF64_9FCC_F645; + +use core::fmt; +use core::mem::transmute; +use rand_core::{RngCore, SeedableRng, Error, le}; + +/// A PCG random number generator (XSL 128/64 (MCG) variant). +/// +/// Permuted Congruential Generator with 128-bit state, internal Multiplicative +/// Congruential Generator, and 64-bit output via "xorshift low (bits), +/// random rotation" output function. +/// +/// This is a 128-bit MCG with the PCG-XSL-RR output function. +/// Note that compared to the standard `pcg64` (128-bit LCG with PCG-XSL-RR +/// output function), this RNG is faster, also has a long cycle, and still has +/// good performance on statistical tests. +/// +/// Note: this RNG is only available using Rust 1.26 or later. +#[derive(Clone)] +#[cfg_attr(feature="serde1", derive(Serialize,Deserialize))] +pub struct Mcg128Xsl64 { + state: u128, +} + +/// A friendly name for `Mcg128Xsl64`. +pub type Pcg64Mcg = Mcg128Xsl64; + +impl Mcg128Xsl64 { + /// Construct an instance compatible with PCG seed. + /// + /// Note that PCG specifies a default value for the parameter: + /// + /// - `state = 0xcafef00dd15ea5e5` + pub fn new(state: u128) -> Self { + // Force low bit to 1, as in C version (C++ uses `state | 3` instead). + Mcg128Xsl64 { state: state | 1 } + } +} + +// Custom Debug implementation that does not expose the internal state +impl fmt::Debug for Mcg128Xsl64 { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + write!(f, "Mcg128Xsl64 {{}}") + } +} + +/// We use a single 126-bit seed to initialise the state and select a stream. +/// Two `seed` bits (lowest order of last byte) are ignored. +impl SeedableRng for Mcg128Xsl64 { + type Seed = [u8; 16]; + + fn from_seed(seed: Self::Seed) -> Self { + // Read as if a little-endian u128 value: + let mut seed_u64 = [0u64; 2]; + le::read_u64_into(&seed, &mut seed_u64); + let state = (seed_u64[0] as u128) | + (seed_u64[1] as u128) << 64; + Mcg128Xsl64::new(state) + } +} + +impl RngCore for Mcg128Xsl64 { + #[inline] + fn next_u32(&mut self) -> u32 { + self.next_u64() as u32 + } + + #[inline] + fn next_u64(&mut self) -> u64 { + // prepare the LCG for the next round + let state = self.state.wrapping_mul(MULTIPLIER); + self.state = state; + + // Output function XSL RR ("xorshift low (bits), random rotation") + // Constants are for 128-bit state, 64-bit output + const XSHIFT: u32 = 64; // (128 - 64 + 64) / 2 + const ROTATE: u32 = 122; // 128 - 6 + + let rot = (state >> ROTATE) as u32; + let xsl = ((state >> XSHIFT) as u64) ^ (state as u64); + xsl.rotate_right(rot) + } + + #[inline] + fn fill_bytes(&mut self, dest: &mut [u8]) { + // specialisation of impls::fill_bytes_via_next; approx 3x faster + let mut left = dest; + while left.len() >= 8 { + let (l, r) = {left}.split_at_mut(8); + left = r; + let chunk: [u8; 8] = unsafe { + transmute(self.next_u64().to_le()) + }; + l.copy_from_slice(&chunk); + } + let n = left.len(); + if n > 0 { + let chunk: [u8; 8] = unsafe { + transmute(self.next_u64().to_le()) + }; + left.copy_from_slice(&chunk[..n]); + } + } + + #[inline] + fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { + Ok(self.fill_bytes(dest)) + } +} diff --git a/rand/rand_pcg/src/pcg64.rs b/rand/rand_pcg/src/pcg64.rs new file mode 100644 index 0000000..9177ec2 --- /dev/null +++ b/rand/rand_pcg/src/pcg64.rs @@ -0,0 +1,141 @@ +// Copyright 2018 Developers of the Rand project. +// Copyright 2017 Paul Dicker. +// Copyright 2014-2017 Melissa O'Neill and PCG Project contributors +// +// 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. + +//! PCG random number generators + +use core::fmt; +use core::mem::transmute; +use rand_core::{RngCore, SeedableRng, Error, le, impls}; + +// This is the default multiplier used by PCG for 64-bit state. +const MULTIPLIER: u64 = 6364136223846793005; + +/// A PCG random number generator (XSH RR 64/32 (LCG) variant). +/// +/// Permuted Congruential Generator with 64-bit state, internal Linear +/// Congruential Generator, and 32-bit output via "xorshift high (bits), +/// random rotation" output function. +/// +/// This is a 64-bit LCG with explicitly chosen stream with the PCG-XSH-RR +/// output function. This combination is the standard `pcg32`. +/// +/// Despite the name, this implementation uses 16 bytes (128 bit) space +/// comprising 64 bits of state and 64 bits stream selector. These are both set +/// by `SeedableRng`, using a 128-bit seed. +#[derive(Clone)] +#[cfg_attr(feature="serde1", derive(Serialize,Deserialize))] +pub struct Lcg64Xsh32 { + state: u64, + increment: u64, +} + +/// `Lcg64Xsh32` is also officially known as `pcg32`. +pub type Pcg32 = Lcg64Xsh32; + +impl Lcg64Xsh32 { + /// Construct an instance compatible with PCG seed and stream. + /// + /// Note that PCG specifies default values for both parameters: + /// + /// - `state = 0xcafef00dd15ea5e5` + /// - `stream = 721347520444481703` + pub fn new(state: u64, stream: u64) -> Self { + // The increment must be odd, hence we discard one bit: + let increment = (stream << 1) | 1; + Lcg64Xsh32::from_state_incr(state, increment) + } + + #[inline] + fn from_state_incr(state: u64, increment: u64) -> Self { + let mut pcg = Lcg64Xsh32 { state, increment }; + // Move away from inital value: + pcg.state = pcg.state.wrapping_add(pcg.increment); + pcg.step(); + pcg + } + + #[inline] + fn step(&mut self) { + // prepare the LCG for the next round + self.state = self.state + .wrapping_mul(MULTIPLIER) + .wrapping_add(self.increment); + } +} + +// Custom Debug implementation that does not expose the internal state +impl fmt::Debug for Lcg64Xsh32 { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + write!(f, "Lcg64Xsh32 {{}}") + } +} + +/// We use a single 127-bit seed to initialise the state and select a stream. +/// One `seed` bit (lowest bit of `seed[8]`) is ignored. +impl SeedableRng for Lcg64Xsh32 { + type Seed = [u8; 16]; + + fn from_seed(seed: Self::Seed) -> Self { + let mut seed_u64 = [0u64; 2]; + le::read_u64_into(&seed, &mut seed_u64); + + // The increment must be odd, hence we discard one bit: + Lcg64Xsh32::from_state_incr(seed_u64[0], seed_u64[1] | 1) + } +} + +impl RngCore for Lcg64Xsh32 { + #[inline] + fn next_u32(&mut self) -> u32 { + let state = self.state; + self.step(); + + // Output function XSH RR: xorshift high (bits), followed by a random rotate + // Constants are for 64-bit state, 32-bit output + const ROTATE: u32 = 59; // 64 - 5 + const XSHIFT: u32 = 18; // (5 + 32) / 2 + const SPARE: u32 = 27; // 64 - 32 - 5 + + let rot = (state >> ROTATE) as u32; + let xsh = (((state >> XSHIFT) ^ state) >> SPARE) as u32; + xsh.rotate_right(rot) + } + + #[inline] + fn next_u64(&mut self) -> u64 { + impls::next_u64_via_u32(self) + } + + #[inline] + fn fill_bytes(&mut self, dest: &mut [u8]) { + // specialisation of impls::fill_bytes_via_next; approx 40% faster + let mut left = dest; + while left.len() >= 4 { + let (l, r) = {left}.split_at_mut(4); + left = r; + let chunk: [u8; 4] = unsafe { + transmute(self.next_u32().to_le()) + }; + l.copy_from_slice(&chunk); + } + let n = left.len(); + if n > 0 { + let chunk: [u8; 4] = unsafe { + transmute(self.next_u32().to_le()) + }; + left.copy_from_slice(&chunk[..n]); + } + } + + #[inline] + fn try_fill_bytes(&mut self, dest: &mut [u8]) -> Result<(), Error> { + Ok(self.fill_bytes(dest)) + } +} diff --git a/rand/rand_pcg/tests/lcg64xsh32.rs b/rand/rand_pcg/tests/lcg64xsh32.rs new file mode 100644 index 0000000..775b12c --- /dev/null +++ b/rand/rand_pcg/tests/lcg64xsh32.rs @@ -0,0 +1,58 @@ +extern crate rand_pcg; +extern crate rand_core; +#[cfg(all(feature="serde1", test))] extern crate bincode; + +use rand_core::{RngCore, SeedableRng}; +use rand_pcg::{Lcg64Xsh32, Pcg32}; + +#[test] +fn test_lcg64xsh32_construction() { + // Test that various construction techniques produce a working RNG. + let seed = [1,2,3,4, 5,6,7,8, 9,10,11,12, 13,14,15,16]; + let mut rng1 = Lcg64Xsh32::from_seed(seed); + assert_eq!(rng1.next_u64(), 1204678643940597513); + + let mut rng2 = Lcg64Xsh32::from_rng(&mut rng1).unwrap(); + assert_eq!(rng2.next_u64(), 12384929573776311845); + + let mut rng3 = Lcg64Xsh32::seed_from_u64(0); + assert_eq!(rng3.next_u64(), 18195738587432868099); + + // This is the same as Lcg64Xsh32, so we only have a single test: + let mut rng4 = Pcg32::seed_from_u64(0); + assert_eq!(rng4.next_u64(), 18195738587432868099); +} + +#[test] +fn test_lcg64xsh32_true_values() { + // Numbers copied from official test suite. + let mut rng = Lcg64Xsh32::new(42, 54); + + let mut results = [0u32; 6]; + for i in results.iter_mut() { *i = rng.next_u32(); } + let expected: [u32; 6] = [0xa15c02b7, 0x7b47f409, 0xba1d3330, + 0x83d2f293, 0xbfa4784b, 0xcbed606e]; + assert_eq!(results, expected); +} + +#[cfg(feature="serde1")] +#[test] +fn test_lcg64xsh32_serde() { + use bincode; + use std::io::{BufWriter, BufReader}; + + let mut rng = Lcg64Xsh32::seed_from_u64(0); + + let buf: Vec<u8> = Vec::new(); + let mut buf = BufWriter::new(buf); + bincode::serialize_into(&mut buf, &rng).expect("Could not serialize"); + + let buf = buf.into_inner().unwrap(); + let mut read = BufReader::new(&buf[..]); + let mut deserialized: Lcg64Xsh32 = bincode::deserialize_from(&mut read) + .expect("Could not deserialize"); + + for _ in 0..16 { + assert_eq!(rng.next_u64(), deserialized.next_u64()); + } +} diff --git a/rand/rand_pcg/tests/mcg128xsl64.rs b/rand/rand_pcg/tests/mcg128xsl64.rs new file mode 100644 index 0000000..2508917 --- /dev/null +++ b/rand/rand_pcg/tests/mcg128xsl64.rs @@ -0,0 +1,59 @@ +#![cfg(rust_1_26)] +extern crate rand_pcg; +extern crate rand_core; +#[cfg(all(feature="serde1", test))] extern crate bincode; + +use rand_core::{RngCore, SeedableRng}; +use rand_pcg::{Mcg128Xsl64, Pcg64Mcg}; + +#[test] +fn test_mcg128xsl64_construction() { + // Test that various construction techniques produce a working RNG. + let seed = [1,2,3,4, 5,6,7,8, 9,10,11,12, 13,14,15,16]; + let mut rng1 = Mcg128Xsl64::from_seed(seed); + assert_eq!(rng1.next_u64(), 7071994460355047496); + + let mut rng2 = Mcg128Xsl64::from_rng(&mut rng1).unwrap(); + assert_eq!(rng2.next_u64(), 12300796107712034932); + + let mut rng3 = Mcg128Xsl64::seed_from_u64(0); + assert_eq!(rng3.next_u64(), 6198063878555692194); + + // This is the same as Mcg128Xsl64, so we only have a single test: + let mut rng4 = Pcg64Mcg::seed_from_u64(0); + assert_eq!(rng4.next_u64(), 6198063878555692194); +} + +#[test] +fn test_mcg128xsl64_true_values() { + // Numbers copied from official test suite (C version). + let mut rng = Mcg128Xsl64::new(42); + + let mut results = [0u64; 6]; + for i in results.iter_mut() { *i = rng.next_u64(); } + let expected: [u64; 6] = [0x63b4a3a813ce700a, 0x382954200617ab24, + 0xa7fd85ae3fe950ce, 0xd715286aa2887737, 0x60c92fee2e59f32c, 0x84c4e96beff30017]; + assert_eq!(results, expected); +} + +#[cfg(feature="serde1")] +#[test] +fn test_mcg128xsl64_serde() { + use bincode; + use std::io::{BufWriter, BufReader}; + + let mut rng = Mcg128Xsl64::seed_from_u64(0); + + let buf: Vec<u8> = Vec::new(); + let mut buf = BufWriter::new(buf); + bincode::serialize_into(&mut buf, &rng).expect("Could not serialize"); + + let buf = buf.into_inner().unwrap(); + let mut read = BufReader::new(&buf[..]); + let mut deserialized: Mcg128Xsl64 = bincode::deserialize_from(&mut read) + .expect("Could not deserialize"); + + for _ in 0..16 { + assert_eq!(rng.next_u64(), deserialized.next_u64()); + } +} |