goroutines coordinate using the <code>limit</code> channel to ensure
that at most three are running work functions at a time.
</p>

<pre>
var limit = make(chan int, 3)

func main() {
	for _, w := range work {
		go func(w func()) {
			limit &lt;- 1
			w()
			&lt;-limit
		}(w)
	}
	select{}
}
</pre>

<h3 id="locks">Locks</h3>

<p>

<code>R15</code> points to the stack frame and should typically only be accessed using the
virtual registers <code>SP</code> and <code>FP</code>.
</p>

<p>
Load- and store-multiple instructions operate on a range of registers.
The range of registers is specified by a start register and an end register.
For example, <code>LMG</code> <code>(R9),</code> <code>R5,</code> <code>R7</code> would load