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@@ -50,14 +50,20 @@ well here. But what allows it to make this optimization? Taking a look at the ge
 reveals the solution: (severely shortened to only show the relevant parts)</p>
 <pre tabindex="0"><code class="language-llvmir" data-lang="llvmir">define void @takes_box_and_ptr_to_it(i8* noalias %0, i8* %ptr) {
 </code></pre><p>See the little attribute on the first parameter called <code>noalias</code>? That’s what’s doing the magic here.
-<code>noalias</code> is quite complex, but for our case here, it says that no other pointers point to (alias) the same location.
-This allows the optimizer to assume that writing to the box pointer doesn’t affect the other pointer - they are
-not allowed to alias (it’s like if they used <code>restrict</code> in C).</p>
+<code>noalias</code> is an LLVM attribute on pointers that allows for various optimizations. If there are two pointers,
+and at least one of them is <code>noalias</code>, there are some restrictions around the two:</p>
+<ul>
+<li>If one of them writes, they must not point to the same value (alias each other)</li>
+<li>If neither of them writes, they can alias just fine.
+Therefore, we also apply <code>noalias</code> to <code>&mut T</code> and <code>&T</code> (if it doesn’t contain interior mutability through
+<code>UnsafeCell<T></code>, since they uphold these rules.</li>
+</ul>
 <p>This might sound familiar to you if you’re a viewer of <a href="https://twitter.com/jonhoo">Jon Gjengset</a>’s content (which I can highly recommend). Jon has made an entire video about this before, since his crate <code>left-right</code>
 was affected by this (<a href="https://youtu.be/EY7Wi9fV5bk)">https://youtu.be/EY7Wi9fV5bk)</a>.</p>
 <p>If you’re looking for <em>any</em> hint that using box emits <code>noalias</code>, you have to look no further than the documentation
 for <a href="https://doc.rust-lang.org/nightly/std/boxed/index.html#considerations-for-unsafe-code"><code>std::boxed</code></a>. Well, the nightly or beta docs, because I only added this section very recently. For years, this behaviour was not really documented, and you had to
-belong to the arcane circles of the select few who were aware of it. So lots of code was written thinking that box was “just a RAII pointer” (a pointer that allocates the value in the constructor, and deallocates it in the destructor on drop) for all
+belong to the arcane circles of the select few who were aware of it. So lots of code was written thinking that box was “just an
+RAII pointer” (a pointer that allocates the value in the constructor, and deallocates it in the destructor on drop) for all
 pointers are concerned.</p>
 <h1 id="stacked-borrows-and-miri">Stacked Borrows and Miri</h1>
 <p><a href="https://github.com/rust-lang/miri">Miri</a> is an interpreter for Rust code with the goal of finding undefinde behaviour.