Update rand

Author: dhardy

src/distr/integer.rs

@@ -112,8 +112,7 @@ impl Distribution<__m128i> for StandardUniform {
     fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> __m128i {
         // NOTE: It's tempting to use the u128 impl here, but confusingly this
         // results in different code (return via rdx, r10 instead of rax, rdx
-        // with u128 impl) and is much slower (+130 time). This version calls
-        // le::fill_bytes_via_next but performs well.
+        // with u128 impl) and is much slower (+130 time).
 
         let mut buf = [0_u8; core::mem::size_of::<__m128i>()];
         rng.fill_bytes(&mut buf);

src/lib.rs

@@ -367,7 +367,7 @@ mod test {
         }
 
         fn fill_bytes(&mut self, dst: &mut [u8]) {
-            rand_core::le::fill_bytes_via_next(self, dst)
+            rand_core::utils::fill_bytes_via_next_word(dst, || self.next_u64());
         }
     }
 

src/rngs/reseeding.rs

@@ -12,10 +12,10 @@
 
 use core::mem::size_of_val;
 
-use rand_core::block::{BlockRng, BlockRngCore, CryptoBlockRng};
+use rand_core::block::{BlockRng, CryptoGenerator, Generator};
 use rand_core::{CryptoRng, RngCore, SeedableRng, TryCryptoRng, TryRngCore};
 
-/// A wrapper around any PRNG that implements [`BlockRngCore`], that adds the
+/// A wrapper around any PRNG that implements [`Generator`], that adds the
 /// ability to reseed it.
 ///
 /// `ReseedingRng` reseeds the underlying PRNG in the following cases:
@@ -53,7 +53,7 @@ use rand_core::{CryptoRng, RngCore, SeedableRng, TryCryptoRng, TryRngCore};
 ///
 /// ```
 /// use chacha20::ChaCha20Core; // Internal part of ChaChaRng that
-///                             // implements BlockRngCore
+///                             // implements Generator
 /// use rand::prelude::*;
 /// use rand::rngs::SysRng;
 /// use rand::rngs::ReseedingRng;
@@ -63,18 +63,18 @@ use rand_core::{CryptoRng, RngCore, SeedableRng, TryCryptoRng, TryRngCore};
 /// println!("{}", reseeding_rng.random::<u64>());
 /// ```
 ///
-/// [`BlockRngCore`]: rand_core::block::BlockRngCore
+/// [`Generator`]: rand_core::block::Generator
 /// [`ReseedingRng::new`]: ReseedingRng::new
 /// [`reseed()`]: ReseedingRng::reseed
 #[derive(Debug)]
-pub struct ReseedingRng<R, Rsdr>(BlockRng<ReseedingCore<R, Rsdr>>)
+pub struct ReseedingRng<G, Rsdr>(BlockRng<ReseedingCore<G, Rsdr>>)
 where
-    R: BlockRngCore + SeedableRng,
+    G: Generator + SeedableRng,
     Rsdr: TryRngCore;
 
-impl<R, Rsdr> ReseedingRng<R, Rsdr>
+impl<const N: usize, G, Rsdr> ReseedingRng<G, Rsdr>
 where
-    R: BlockRngCore + SeedableRng,
+    G: Generator<Output = [u32; N]> + SeedableRng,
     Rsdr: TryRngCore,
 {
     /// Create a new `ReseedingRng` from an existing PRNG, combined with a RNG
@@ -100,71 +100,70 @@ where
 
 // TODO: this should be implemented for any type where the inner type
 // implements RngCore, but we can't specify that because ReseedingCore is private
-impl<R, Rsdr> RngCore for ReseedingRng<R, Rsdr>
+impl<const N: usize, G, Rsdr> RngCore for ReseedingRng<G, Rsdr>
 where
-    R: BlockRngCore<Item = u32> + SeedableRng,
+    G: Generator<Output = [u32; N]> + SeedableRng,
     Rsdr: TryRngCore,
 {
     #[inline(always)]
     fn next_u32(&mut self) -> u32 {
-        self.0.next_u32()
+        self.0.next_word()
     }
 
     #[inline(always)]
     fn next_u64(&mut self) -> u64 {
-        self.0.next_u64()
+        self.0.next_u64_from_u32()
     }
 
     fn fill_bytes(&mut self, dest: &mut [u8]) {
         self.0.fill_bytes(dest)
     }
 }
 
-impl<R, Rsdr> CryptoRng for ReseedingRng<R, Rsdr>
+impl<const N: usize, G, Rsdr> CryptoRng for ReseedingRng<G, Rsdr>
 where
-    R: BlockRngCore<Item = u32> + SeedableRng + CryptoBlockRng,
+    G: Generator<Output = [u32; N]> + SeedableRng + CryptoGenerator,
     Rsdr: TryCryptoRng,
 {
 }
 
 #[derive(Debug)]
-struct ReseedingCore<R, Rsdr> {
-    inner: R,
+struct ReseedingCore<G, Rsdr> {
+    inner: G,
     reseeder: Rsdr,
     threshold: i64,
     bytes_until_reseed: i64,
 }
 
-impl<R, Rsdr> BlockRngCore for ReseedingCore<R, Rsdr>
+impl<G, Rsdr> Generator for ReseedingCore<G, Rsdr>
 where
-    R: BlockRngCore + SeedableRng,
+    G: Generator + SeedableRng,
     Rsdr: TryRngCore,
 {
-    type Item = <R as BlockRngCore>::Item;
-    type Results = <R as BlockRngCore>::Results;
+    type Output = <G as Generator>::Output;
 
-    fn generate(&mut self, results: &mut Self::Results) {
+    fn generate(&mut self, results: &mut Self::Output) {
         if self.bytes_until_reseed <= 0 {
             // We get better performance by not calling only `reseed` here
             // and continuing with the rest of the function, but by directly
             // returning from a non-inlined function.
             return self.reseed_and_generate(results);
         }
-        let num_bytes = size_of_val(results.as_ref());
+        let num_bytes = size_of_val(results);
         self.bytes_until_reseed -= num_bytes as i64;
         self.inner.generate(results);
     }
 }
 
-impl<R, Rsdr> ReseedingCore<R, Rsdr>
+impl<G, Rsdr> ReseedingCore<G, Rsdr>
 where
-    R: BlockRngCore + SeedableRng,
+    G: Generator + SeedableRng,
     Rsdr: TryRngCore,
 {
     /// Create a new `ReseedingCore`.
     ///
     /// `threshold` is the maximum number of bytes produced by
-    /// [`BlockRngCore::generate`] before attempting reseeding.
+    /// [`Generator::generate`] before attempting reseeding.
     fn new(threshold: u64, mut reseeder: Rsdr) -> Result<Self, Rsdr::Error> {
         // Because generating more values than `i64::MAX` takes centuries on
         // current hardware, we just clamp to that value.
@@ -178,7 +177,7 @@ where
             i64::MAX
         };
 
-        let inner = R::try_from_rng(&mut reseeder)?;
+        let inner = G::try_from_rng(&mut reseeder)?;
 
         Ok(ReseedingCore {
             inner,
@@ -190,17 +189,17 @@ where
 
     /// Reseed the internal PRNG.
     fn reseed(&mut self) -> Result<(), Rsdr::Error> {
-        R::try_from_rng(&mut self.reseeder).map(|result| {
+        G::try_from_rng(&mut self.reseeder).map(|result| {
             self.bytes_until_reseed = self.threshold;
             self.inner = result
         })
     }
 
     #[inline(never)]
-    fn reseed_and_generate(&mut self, results: &mut <Self as BlockRngCore>::Results) {
+    fn reseed_and_generate(&mut self, results: &mut G::Output) {
         trace!("Reseeding RNG (periodic reseed)");
 
-        let num_bytes = size_of_val(results.as_ref());
+        let num_bytes = size_of_val(results);
 
         if let Err(e) = self.reseed() {
             warn!("Reseeding RNG failed: {}", e);
@@ -212,9 +211,9 @@ where
     }
 }
 
-impl<R, Rsdr> CryptoBlockRng for ReseedingCore<R, Rsdr>
+impl<G, Rsdr> CryptoGenerator for ReseedingCore<G, Rsdr>
 where
-    R: BlockRngCore<Item = u32> + SeedableRng + CryptoBlockRng,
+    G: Generator + SeedableRng + CryptoGenerator,
     Rsdr: TryCryptoRng,
 {
 }

src/rngs/xoshiro128plusplus.rs

@@ -6,7 +6,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use rand_core::{RngCore, SeedableRng, le};
+use rand_core::{RngCore, SeedableRng, utils};
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
@@ -31,8 +31,7 @@ impl SeedableRng for Xoshiro128PlusPlus {
     /// mapped to a different seed.
     #[inline]
     fn from_seed(seed: [u8; 16]) -> Xoshiro128PlusPlus {
-        let mut state = [0; 4];
-        le::read_u32_into(&seed, &mut state);
+        let state = utils::read_words(&seed);
         // Check for zero on aligned integers for better code generation.
         // Furtermore, seed_from_u64(0) will expand to a constant when optimized.
         if state.iter().all(|&x| x == 0) {
@@ -88,12 +87,12 @@ impl RngCore for Xoshiro128PlusPlus {
 
     #[inline]
     fn next_u64(&mut self) -> u64 {
-        le::next_u64_via_u32(self)
+        utils::next_u64_via_u32(self)
     }
 
     #[inline]
     fn fill_bytes(&mut self, dst: &mut [u8]) {
-        le::fill_bytes_via_next(self, dst)
+        utils::fill_bytes_via_next_word(dst, || self.next_u32());
     }
 }
 

src/rngs/xoshiro256plusplus.rs

@@ -6,7 +6,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-use rand_core::{RngCore, SeedableRng, le};
+use rand_core::{RngCore, SeedableRng, utils};
 #[cfg(feature = "serde")]
 use serde::{Deserialize, Serialize};
 
@@ -31,8 +31,7 @@ impl SeedableRng for Xoshiro256PlusPlus {
     /// mapped to a different seed.
     #[inline]
     fn from_seed(seed: [u8; 32]) -> Xoshiro256PlusPlus {
-        let mut state = [0; 4];
-        le::read_u64_into(&seed, &mut state);
+        let state = utils::read_words(&seed);
         // Check for zero on aligned integers for better code generation.
         // Furtermore, seed_from_u64(0) will expand to a constant when optimized.
         if state.iter().all(|&x| x == 0) {
@@ -95,7 +94,7 @@ impl RngCore for Xoshiro256PlusPlus {
 
     #[inline]
     fn fill_bytes(&mut self, dst: &mut [u8]) {
-        le::fill_bytes_via_next(self, dst)
+        utils::fill_bytes_via_next_word(dst, || self.next_u64());
     }
 }