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| </pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project.</span> |
| <span class="comment">//</span> |
| <span class="comment">// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or</span> |
| <span class="comment">// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license</span> |
| <span class="comment">// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your</span> |
| <span class="comment">// option. This file may not be copied, modified, or distributed</span> |
| <span class="comment">// except according to those terms.</span> |
| |
| <span class="doccomment">//! Helper functions for implementing `RngCore` functions.</span> |
| <span class="doccomment">//!</span> |
| <span class="doccomment">//! For cross-platform reproducibility, these functions all use Little Endian:</span> |
| <span class="doccomment">//! least-significant part first. For example, `next_u64_via_u32` takes `u32`</span> |
| <span class="doccomment">//! values `x, y`, then outputs `(y << 32) | x`. To implement `next_u32`</span> |
| <span class="doccomment">//! from `next_u64` in little-endian order, one should use `next_u64() as u32`.</span> |
| <span class="doccomment">//!</span> |
| <span class="doccomment">//! Byte-swapping (like the std `to_le` functions) is only needed to convert</span> |
| <span class="doccomment">//! to/from byte sequences, and since its purpose is reproducibility,</span> |
| <span class="doccomment">//! non-reproducible sources (e.g. `OsRng`) need not bother with it.</span> |
| |
| <span class="kw">use</span> <span class="ident"><span class="kw">crate</span>::RngCore</span>; |
| <span class="kw">use</span> <span class="ident">core::cmp::min</span>; |
| |
| <span class="doccomment">/// Implement `next_u64` via `next_u32`, little-endian order.</span> |
| <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">next_u64_via_u32</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">RngCore</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span>(<span class="ident">rng</span>: <span class="kw-2">&mut</span> <span class="ident">R</span>) -> <span class="ident">u64</span> { |
| <span class="comment">// Use LE; we explicitly generate one value before the next.</span> |
| <span class="kw">let</span> <span class="ident">x</span> <span class="op">=</span> <span class="ident">u64::from</span>(<span class="ident">rng</span>.<span class="ident">next_u32</span>()); |
| <span class="kw">let</span> <span class="ident">y</span> <span class="op">=</span> <span class="ident">u64::from</span>(<span class="ident">rng</span>.<span class="ident">next_u32</span>()); |
| (<span class="ident">y</span> <span class="op"><</span><span class="op"><</span> <span class="number">32</span>) <span class="op">|</span> <span class="ident">x</span> |
| } |
| |
| <span class="doccomment">/// Implement `fill_bytes` via `next_u64` and `next_u32`, little-endian order.</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// The fastest way to fill a slice is usually to work as long as possible with</span> |
| <span class="doccomment">/// integers. That is why this method mostly uses `next_u64`, and only when</span> |
| <span class="doccomment">/// there are 4 or less bytes remaining at the end of the slice it uses</span> |
| <span class="doccomment">/// `next_u32` once.</span> |
| <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">fill_bytes_via_next</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">RngCore</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span>(<span class="ident">rng</span>: <span class="kw-2">&mut</span> <span class="ident">R</span>, <span class="ident">dest</span>: <span class="kw-2">&mut</span> [<span class="ident">u8</span>]) { |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">left</span> <span class="op">=</span> <span class="ident">dest</span>; |
| <span class="kw">while</span> <span class="ident">left</span>.<span class="ident">len</span>() <span class="op">></span><span class="op">=</span> <span class="number">8</span> { |
| <span class="kw">let</span> (<span class="ident">l</span>, <span class="ident">r</span>) <span class="op">=</span> { <span class="ident">left</span> }.<span class="ident">split_at_mut</span>(<span class="number">8</span>); |
| <span class="ident">left</span> <span class="op">=</span> <span class="ident">r</span>; |
| <span class="kw">let</span> <span class="ident">chunk</span>: [<span class="ident">u8</span>; <span class="number">8</span>] <span class="op">=</span> <span class="ident">rng</span>.<span class="ident">next_u64</span>().<span class="ident">to_le_bytes</span>(); |
| <span class="ident">l</span>.<span class="ident">copy_from_slice</span>(<span class="kw-2">&</span><span class="ident">chunk</span>); |
| } |
| <span class="kw">let</span> <span class="ident">n</span> <span class="op">=</span> <span class="ident">left</span>.<span class="ident">len</span>(); |
| <span class="kw">if</span> <span class="ident">n</span> <span class="op">></span> <span class="number">4</span> { |
| <span class="kw">let</span> <span class="ident">chunk</span>: [<span class="ident">u8</span>; <span class="number">8</span>] <span class="op">=</span> <span class="ident">rng</span>.<span class="ident">next_u64</span>().<span class="ident">to_le_bytes</span>(); |
| <span class="ident">left</span>.<span class="ident">copy_from_slice</span>(<span class="kw-2">&</span><span class="ident">chunk</span>[..<span class="ident">n</span>]); |
| } <span class="kw">else</span> <span class="kw">if</span> <span class="ident">n</span> <span class="op">></span> <span class="number">0</span> { |
| <span class="kw">let</span> <span class="ident">chunk</span>: [<span class="ident">u8</span>; <span class="number">4</span>] <span class="op">=</span> <span class="ident">rng</span>.<span class="ident">next_u32</span>().<span class="ident">to_le_bytes</span>(); |
| <span class="ident">left</span>.<span class="ident">copy_from_slice</span>(<span class="kw-2">&</span><span class="ident">chunk</span>[..<span class="ident">n</span>]); |
| } |
| } |
| |
| <span class="kw">trait</span> <span class="ident">Observable</span>: <span class="ident">Copy</span> { |
| <span class="kw">type</span> <span class="ident">Bytes</span>: <span class="ident">AsRef</span><span class="op"><</span>[<span class="ident">u8</span>]<span class="op">></span>; |
| <span class="kw">fn</span> <span class="ident">to_le_bytes</span>(<span class="self">self</span>) -> <span class="ident"><span class="self">Self</span>::Bytes</span>; |
| |
| <span class="comment">// Contract: observing self is memory-safe (implies no uninitialised padding)</span> |
| <span class="kw">fn</span> <span class="ident">as_byte_slice</span>(<span class="ident">x</span>: <span class="kw-2">&</span>[<span class="self">Self</span>]) -> <span class="kw-2">&</span>[<span class="ident">u8</span>]; |
| } |
| <span class="kw">impl</span> <span class="ident">Observable</span> <span class="kw">for</span> <span class="ident">u32</span> { |
| <span class="kw">type</span> <span class="ident">Bytes</span> <span class="op">=</span> [<span class="ident">u8</span>; <span class="number">4</span>]; |
| <span class="kw">fn</span> <span class="ident">to_le_bytes</span>(<span class="self">self</span>) -> <span class="ident"><span class="self">Self</span>::Bytes</span> { |
| <span class="self">self</span>.<span class="ident">to_le_bytes</span>() |
| } |
| <span class="kw">fn</span> <span class="ident">as_byte_slice</span>(<span class="ident">x</span>: <span class="kw-2">&</span>[<span class="self">Self</span>]) -> <span class="kw-2">&</span>[<span class="ident">u8</span>] { |
| <span class="kw">let</span> <span class="ident">ptr</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">as_ptr</span>() <span class="kw">as</span> <span class="kw-2">*const</span> <span class="ident">u8</span>; |
| <span class="kw">let</span> <span class="ident">len</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">len</span>() <span class="op">*</span> <span class="ident">core::mem::size_of</span>::<span class="op"><</span><span class="self">Self</span><span class="op">></span>(); |
| <span class="kw">unsafe</span> { <span class="ident">core::slice::from_raw_parts</span>(<span class="ident">ptr</span>, <span class="ident">len</span>) } |
| } |
| } |
| <span class="kw">impl</span> <span class="ident">Observable</span> <span class="kw">for</span> <span class="ident">u64</span> { |
| <span class="kw">type</span> <span class="ident">Bytes</span> <span class="op">=</span> [<span class="ident">u8</span>; <span class="number">8</span>]; |
| <span class="kw">fn</span> <span class="ident">to_le_bytes</span>(<span class="self">self</span>) -> <span class="ident"><span class="self">Self</span>::Bytes</span> { |
| <span class="self">self</span>.<span class="ident">to_le_bytes</span>() |
| } |
| <span class="kw">fn</span> <span class="ident">as_byte_slice</span>(<span class="ident">x</span>: <span class="kw-2">&</span>[<span class="self">Self</span>]) -> <span class="kw-2">&</span>[<span class="ident">u8</span>] { |
| <span class="kw">let</span> <span class="ident">ptr</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">as_ptr</span>() <span class="kw">as</span> <span class="kw-2">*const</span> <span class="ident">u8</span>; |
| <span class="kw">let</span> <span class="ident">len</span> <span class="op">=</span> <span class="ident">x</span>.<span class="ident">len</span>() <span class="op">*</span> <span class="ident">core::mem::size_of</span>::<span class="op"><</span><span class="self">Self</span><span class="op">></span>(); |
| <span class="kw">unsafe</span> { <span class="ident">core::slice::from_raw_parts</span>(<span class="ident">ptr</span>, <span class="ident">len</span>) } |
| } |
| } |
| |
| <span class="kw">fn</span> <span class="ident">fill_via_chunks</span><span class="op"><</span><span class="ident">T</span>: <span class="ident">Observable</span><span class="op">></span>(<span class="ident">src</span>: <span class="kw-2">&</span>[<span class="ident">T</span>], <span class="ident">dest</span>: <span class="kw-2">&mut</span> [<span class="ident">u8</span>]) -> (<span class="ident">usize</span>, <span class="ident">usize</span>) { |
| <span class="kw">let</span> <span class="ident">size</span> <span class="op">=</span> <span class="ident">core::mem::size_of</span>::<span class="op"><</span><span class="ident">T</span><span class="op">></span>(); |
| <span class="kw">let</span> <span class="ident">byte_len</span> <span class="op">=</span> <span class="ident">min</span>(<span class="ident">src</span>.<span class="ident">len</span>() <span class="op">*</span> <span class="ident">size</span>, <span class="ident">dest</span>.<span class="ident">len</span>()); |
| <span class="kw">let</span> <span class="ident">num_chunks</span> <span class="op">=</span> (<span class="ident">byte_len</span> <span class="op">+</span> <span class="ident">size</span> <span class="op">-</span> <span class="number">1</span>) <span class="op">/</span> <span class="ident">size</span>; |
| |
| <span class="kw">if</span> <span class="macro">cfg!</span>(<span class="ident">target_endian</span> <span class="op">=</span> <span class="string">"little"</span>) { |
| <span class="comment">// On LE we can do a simple copy, which is 25-50% faster:</span> |
| <span class="ident">dest</span>[..<span class="ident">byte_len</span>].<span class="ident">copy_from_slice</span>(<span class="kw-2">&</span><span class="ident">T::as_byte_slice</span>(<span class="kw-2">&</span><span class="ident">src</span>[..<span class="ident">num_chunks</span>])[..<span class="ident">byte_len</span>]); |
| } <span class="kw">else</span> { |
| <span class="comment">// This code is valid on all arches, but slower than the above:</span> |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">i</span> <span class="op">=</span> <span class="number">0</span>; |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">iter</span> <span class="op">=</span> <span class="ident">dest</span>[..<span class="ident">byte_len</span>].<span class="ident">chunks_exact_mut</span>(<span class="ident">size</span>); |
| <span class="kw">for</span> <span class="ident">chunk</span> <span class="kw">in</span> <span class="kw-2">&mut</span> <span class="ident">iter</span> { |
| <span class="ident">chunk</span>.<span class="ident">copy_from_slice</span>(<span class="ident">src</span>[<span class="ident">i</span>].<span class="ident">to_le_bytes</span>().<span class="ident">as_ref</span>()); |
| <span class="ident">i</span> <span class="op">+</span><span class="op">=</span> <span class="number">1</span>; |
| } |
| <span class="kw">let</span> <span class="ident">chunk</span> <span class="op">=</span> <span class="ident">iter</span>.<span class="ident">into_remainder</span>(); |
| <span class="kw">if</span> <span class="op">!</span><span class="ident">chunk</span>.<span class="ident">is_empty</span>() { |
| <span class="ident">chunk</span>.<span class="ident">copy_from_slice</span>(<span class="kw-2">&</span><span class="ident">src</span>[<span class="ident">i</span>].<span class="ident">to_le_bytes</span>().<span class="ident">as_ref</span>()[..<span class="ident">chunk</span>.<span class="ident">len</span>()]); |
| } |
| } |
| |
| (<span class="ident">num_chunks</span>, <span class="ident">byte_len</span>) |
| } |
| |
| <span class="doccomment">/// Implement `fill_bytes` by reading chunks from the output buffer of a block</span> |
| <span class="doccomment">/// based RNG.</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// The return values are `(consumed_u32, filled_u8)`.</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// `filled_u8` is the number of filled bytes in `dest`, which may be less than</span> |
| <span class="doccomment">/// the length of `dest`.</span> |
| <span class="doccomment">/// `consumed_u32` is the number of words consumed from `src`, which is the same</span> |
| <span class="doccomment">/// as `filled_u8 / 4` rounded up.</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// # Example</span> |
| <span class="doccomment">/// (from `IsaacRng`)</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// ```ignore</span> |
| <span class="doccomment">/// fn fill_bytes(&mut self, dest: &mut [u8]) {</span> |
| <span class="doccomment">/// let mut read_len = 0;</span> |
| <span class="doccomment">/// while read_len < dest.len() {</span> |
| <span class="doccomment">/// if self.index >= self.rsl.len() {</span> |
| <span class="doccomment">/// self.isaac();</span> |
| <span class="doccomment">/// }</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// let (consumed_u32, filled_u8) =</span> |
| <span class="doccomment">/// impls::fill_via_u32_chunks(&mut self.rsl[self.index..],</span> |
| <span class="doccomment">/// &mut dest[read_len..]);</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// self.index += consumed_u32;</span> |
| <span class="doccomment">/// read_len += filled_u8;</span> |
| <span class="doccomment">/// }</span> |
| <span class="doccomment">/// }</span> |
| <span class="doccomment">/// ```</span> |
| <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">fill_via_u32_chunks</span>(<span class="ident">src</span>: <span class="kw-2">&</span>[<span class="ident">u32</span>], <span class="ident">dest</span>: <span class="kw-2">&mut</span> [<span class="ident">u8</span>]) -> (<span class="ident">usize</span>, <span class="ident">usize</span>) { |
| <span class="ident">fill_via_chunks</span>(<span class="ident">src</span>, <span class="ident">dest</span>) |
| } |
| |
| <span class="doccomment">/// Implement `fill_bytes` by reading chunks from the output buffer of a block</span> |
| <span class="doccomment">/// based RNG.</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// The return values are `(consumed_u64, filled_u8)`.</span> |
| <span class="doccomment">/// `filled_u8` is the number of filled bytes in `dest`, which may be less than</span> |
| <span class="doccomment">/// the length of `dest`.</span> |
| <span class="doccomment">/// `consumed_u64` is the number of words consumed from `src`, which is the same</span> |
| <span class="doccomment">/// as `filled_u8 / 8` rounded up.</span> |
| <span class="doccomment">///</span> |
| <span class="doccomment">/// See `fill_via_u32_chunks` for an example.</span> |
| <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">fill_via_u64_chunks</span>(<span class="ident">src</span>: <span class="kw-2">&</span>[<span class="ident">u64</span>], <span class="ident">dest</span>: <span class="kw-2">&mut</span> [<span class="ident">u8</span>]) -> (<span class="ident">usize</span>, <span class="ident">usize</span>) { |
| <span class="ident">fill_via_chunks</span>(<span class="ident">src</span>, <span class="ident">dest</span>) |
| } |
| |
| <span class="doccomment">/// Implement `next_u32` via `fill_bytes`, little-endian order.</span> |
| <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">next_u32_via_fill</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">RngCore</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span>(<span class="ident">rng</span>: <span class="kw-2">&mut</span> <span class="ident">R</span>) -> <span class="ident">u32</span> { |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">buf</span> <span class="op">=</span> [<span class="number">0</span>; <span class="number">4</span>]; |
| <span class="ident">rng</span>.<span class="ident">fill_bytes</span>(<span class="kw-2">&mut</span> <span class="ident">buf</span>); |
| <span class="ident">u32::from_le_bytes</span>(<span class="ident">buf</span>) |
| } |
| |
| <span class="doccomment">/// Implement `next_u64` via `fill_bytes`, little-endian order.</span> |
| <span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">next_u64_via_fill</span><span class="op"><</span><span class="ident">R</span>: <span class="ident">RngCore</span> <span class="op">+</span> <span class="question-mark">?</span><span class="ident">Sized</span><span class="op">></span>(<span class="ident">rng</span>: <span class="kw-2">&mut</span> <span class="ident">R</span>) -> <span class="ident">u64</span> { |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">buf</span> <span class="op">=</span> [<span class="number">0</span>; <span class="number">8</span>]; |
| <span class="ident">rng</span>.<span class="ident">fill_bytes</span>(<span class="kw-2">&mut</span> <span class="ident">buf</span>); |
| <span class="ident">u64::from_le_bytes</span>(<span class="ident">buf</span>) |
| } |
| |
| <span class="attribute">#[<span class="ident">cfg</span>(<span class="ident">test</span>)]</span> |
| <span class="kw">mod</span> <span class="ident">test</span> { |
| <span class="kw">use</span> <span class="kw">super</span>::<span class="kw-2">*</span>; |
| |
| <span class="attribute">#[<span class="ident">test</span>]</span> |
| <span class="kw">fn</span> <span class="ident">test_fill_via_u32_chunks</span>() { |
| <span class="kw">let</span> <span class="ident">src</span> <span class="op">=</span> [<span class="number">1</span>, <span class="number">2</span>, <span class="number">3</span>]; |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">dst</span> <span class="op">=</span> [<span class="number">0u8</span>; <span class="number">11</span>]; |
| <span class="macro">assert_eq!</span>(<span class="ident">fill_via_u32_chunks</span>(<span class="kw-2">&</span><span class="ident">src</span>, <span class="kw-2">&mut</span> <span class="ident">dst</span>), (<span class="number">3</span>, <span class="number">11</span>)); |
| <span class="macro">assert_eq!</span>(<span class="ident">dst</span>, [<span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">2</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">3</span>, <span class="number">0</span>, <span class="number">0</span>]); |
| |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">dst</span> <span class="op">=</span> [<span class="number">0u8</span>; <span class="number">13</span>]; |
| <span class="macro">assert_eq!</span>(<span class="ident">fill_via_u32_chunks</span>(<span class="kw-2">&</span><span class="ident">src</span>, <span class="kw-2">&mut</span> <span class="ident">dst</span>), (<span class="number">3</span>, <span class="number">12</span>)); |
| <span class="macro">assert_eq!</span>(<span class="ident">dst</span>, [<span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">2</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">3</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>]); |
| |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">dst</span> <span class="op">=</span> [<span class="number">0u8</span>; <span class="number">5</span>]; |
| <span class="macro">assert_eq!</span>(<span class="ident">fill_via_u32_chunks</span>(<span class="kw-2">&</span><span class="ident">src</span>, <span class="kw-2">&mut</span> <span class="ident">dst</span>), (<span class="number">2</span>, <span class="number">5</span>)); |
| <span class="macro">assert_eq!</span>(<span class="ident">dst</span>, [<span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">2</span>]); |
| } |
| |
| <span class="attribute">#[<span class="ident">test</span>]</span> |
| <span class="kw">fn</span> <span class="ident">test_fill_via_u64_chunks</span>() { |
| <span class="kw">let</span> <span class="ident">src</span> <span class="op">=</span> [<span class="number">1</span>, <span class="number">2</span>]; |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">dst</span> <span class="op">=</span> [<span class="number">0u8</span>; <span class="number">11</span>]; |
| <span class="macro">assert_eq!</span>(<span class="ident">fill_via_u64_chunks</span>(<span class="kw-2">&</span><span class="ident">src</span>, <span class="kw-2">&mut</span> <span class="ident">dst</span>), (<span class="number">2</span>, <span class="number">11</span>)); |
| <span class="macro">assert_eq!</span>(<span class="ident">dst</span>, [<span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">2</span>, <span class="number">0</span>, <span class="number">0</span>]); |
| |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">dst</span> <span class="op">=</span> [<span class="number">0u8</span>; <span class="number">17</span>]; |
| <span class="macro">assert_eq!</span>(<span class="ident">fill_via_u64_chunks</span>(<span class="kw-2">&</span><span class="ident">src</span>, <span class="kw-2">&mut</span> <span class="ident">dst</span>), (<span class="number">2</span>, <span class="number">16</span>)); |
| <span class="macro">assert_eq!</span>(<span class="ident">dst</span>, [<span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">2</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>]); |
| |
| <span class="kw">let</span> <span class="kw-2">mut</span> <span class="ident">dst</span> <span class="op">=</span> [<span class="number">0u8</span>; <span class="number">5</span>]; |
| <span class="macro">assert_eq!</span>(<span class="ident">fill_via_u64_chunks</span>(<span class="kw-2">&</span><span class="ident">src</span>, <span class="kw-2">&mut</span> <span class="ident">dst</span>), (<span class="number">1</span>, <span class="number">5</span>)); |
| <span class="macro">assert_eq!</span>(<span class="ident">dst</span>, [<span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>]); |
| } |
| } |
| </code></pre></div> |
| </section><section id="search" class="content hidden"></section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="rand_core" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.60.0-nightly (1bd4fdc94 2022-01-12)" ></div> |
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