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-rw-r--r--rand/rand_pcg/CHANGELOG.md14
-rw-r--r--rand/rand_pcg/COPYRIGHT12
-rw-r--r--rand/rand_pcg/Cargo.toml37
-rw-r--r--rand/rand_pcg/LICENSE-APACHE201
-rw-r--r--rand/rand_pcg/LICENSE-MIT26
-rw-r--r--rand/rand_pcg/README.md51
-rw-r--r--rand/rand_pcg/build.rs8
-rw-r--r--rand/rand_pcg/src/lib.rs48
-rw-r--r--rand/rand_pcg/src/pcg128.rs122
-rw-r--r--rand/rand_pcg/src/pcg64.rs141
-rw-r--r--rand/rand_pcg/tests/lcg64xsh32.rs58
-rw-r--r--rand/rand_pcg/tests/mcg128xsl64.rs59
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
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+ https://www.apache.org/licenses/
+
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+ whether in tort (including negligence), contract, or otherwise,
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diff --git a/rand/rand_pcg/LICENSE-MIT b/rand/rand_pcg/LICENSE-MIT
new file mode 100644
index 0000000..d46f058
--- /dev/null
+++ b/rand/rand_pcg/LICENSE-MIT
@@ -0,0 +1,26 @@
+Copyright (c) 2014-2017 Melissa O'Neill and PCG Project contributors
+Copyright 2018 Developers of the Rand project
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. 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
+
+[![Build Status](https://travis-ci.org/rust-random/rand.svg?branch=master)](https://travis-ci.org/rust-random/rand)
+[![Build Status](https://ci.appveyor.com/api/projects/status/github/rust-random/rand?svg=true)](https://ci.appveyor.com/project/rust-random/rand)
+[![Latest version](https://img.shields.io/crates/v/rand_pcg.svg)](https://crates.io/crates/rand_pcg)
+[[![Book](https://img.shields.io/badge/book-master-yellow.svg)](https://rust-random.github.io/book/)
+[![API](https://img.shields.io/badge/api-master-yellow.svg)](https://rust-random.github.io/rand/rand_pcg)
+[![API](https://docs.rs/rand_pcg/badge.svg)](https://docs.rs/rand_pcg)
+[![Minimum rustc version](https://img.shields.io/badge/rustc-1.22+-lightgray.svg)](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());
+ }
+}