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-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
3 files changed, 0 insertions, 311 deletions
diff --git a/rand/rand_pcg/src/lib.rs b/rand/rand_pcg/src/lib.rs
deleted file mode 100644
index 9648e85..0000000
--- a/rand/rand_pcg/src/lib.rs
+++ /dev/null
@@ -1,48 +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.
-
-//! 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]
-
-pub extern crate rand_core;
-
-#[cfg(feature="serde1")] extern crate serde;
-#[cfg(feature="serde1")] #[macro_use] extern crate serde_derive;
-
-mod pcg64;
-#[cfg(all(rustc_1_26, not(target_os = "emscripten")))] mod pcg128;
-
-pub use self::pcg64::{Pcg32, Lcg64Xsh32};
-#[cfg(all(rustc_1_26, not(target_os = "emscripten")))] pub use self::pcg128::{Pcg64Mcg, Mcg128Xsl64};
diff --git a/rand/rand_pcg/src/pcg128.rs b/rand/rand_pcg/src/pcg128.rs
deleted file mode 100644
index 9aff506..0000000
--- a/rand/rand_pcg/src/pcg128.rs
+++ /dev/null
@@ -1,122 +0,0 @@
-// 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
deleted file mode 100644
index 9177ec2..0000000
--- a/rand/rand_pcg/src/pcg64.rs
+++ /dev/null
@@ -1,141 +0,0 @@
-// 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))
- }
-}
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