<pre>
i := *p
if i &lt; 0 || i &gt;= len(funcs) {
	panic("invalid function index")
}
... complex code ...
// compiler must NOT reload i = *p here
funcs[i]()
</pre>

<p>
If the complex code needs many registers, a compiler for single-threaded programs
could discard <code>i</code> without saving a copy and then reload
<code>i = *p</code> just before
<code>funcs[i]()</code>.

<a href="/pkg/math/rand/v2/#Uint64N"><code>Uint64N</code></a>
but works for any integer type.
For example a random duration from 0 up to 5 minutes is
<code>rand.N(5*time.Minute)</code>.

<li>The Mitchell & Reeds LFSR generator provided by
<a href="/pkg/math/rand/#Source"><code>math/rand</code>’s <code>Source</code></a>
has been replaced by two more modern pseudo-random generator sources:

Some of the details map precisely to the machine, but some do not.
This is because the compiler suite (see
<a href="https://9p.io/sys/doc/compiler.html">this description</a>)
needs no assembler pass in the usual pipeline.
Instead, the compiler operates on a kind of semi-abstract instruction set,
and instruction selection occurs partly after code generation.
The assembler works on the semi-abstract form, so