</p>

<pre>
switch tag {
default: s3()
case 0, 1, 2, 3: s1()
case 4, 5, 6, 7: s2()
}

switch x := f(); {  // missing switch expression means "true"
case x &lt; 0: return -x
default: return x
}

switch {
case x &lt; y: f1()
case x &lt; z: f2()
case x == 4: f3()
}
</pre>

<p>

One is to update the assembler to support that instruction, which is straightforward
but only worthwhile if it's likely the instruction will be used again.
Instead, for simple one-off cases, it's possible to use the <code>BYTE</code>
and <code>WORD</code> directives
to lay down explicit data into the instruction stream within a <code>TEXT</code>.
Here's how the 386 runtime defines the 64-bit atomic load function.

</p>

<pre>
switch tag {
default: s3()
case 0, 1, 2, 3: s1()
case 4, 5, 6, 7: s2()
}

switch x := f(); {  // missing switch expression means "true"
case x &lt; 0: return -x
default: return x
}

switch {
case x &lt; y: f1()
case x &lt; z: f2()
case x == 4: f3()
}
</pre>

<p>