<h2 id="ports">Ports</h2>

<h3 id="darwin">Darwin</h3>
<p><!-- CL 461697 -->
  On macOS on 64-bit x86 architecture (the <code>darwin/amd64</code> port),
  the Go toolchain now generates position-independent executables (PIE) by default.
  Non-PIE binaries can be generated by specifying the <code>-buildmode=exe</code>
  build flag.
  On 64-bit ARM-based macOS (the <code>darwin/arm64</code> port),
  the Go toolchain already generates PIE by default.

</p>

<pre>
const (
	bit0, mask0 = 1 &lt;&lt; iota, 1&lt;&lt;iota - 1  // bit0 == 1, mask0 == 0  (iota == 0)
	bit1, mask1                           // bit1 == 2, mask1 == 1  (iota == 1)
	_, _                                  //                        (iota == 2, unused)
	bit3, mask3                           // bit3 == 8, mask3 == 7  (iota == 3)
)
</pre>

<p>

</p>

<pre>
const (
	bit0, mask0 = 1 &lt;&lt; iota, 1&lt;&lt;iota - 1  // bit0 == 1, mask0 == 0  (iota == 0)
	bit1, mask1                           // bit1 == 2, mask1 == 1  (iota == 1)
	_, _                                  //                        (iota == 2, unused)
	bit3, mask3                           // bit3 == 8, mask3 == 7  (iota == 3)
)
</pre>

<p>

<code>UXTB</code>: extract an 8-bit value from the low-order bits of <code>R0</code> and zero-extend it to the size of <code>R0</code>.
<code>R0.UXTB&lt;&lt;imm</code>: left shift the result of <code>R0.UXTB</code> by <code>imm</code> bits.
The <code>imm</code> value can be 0, 1, 2, 3, or 4.
The other extensions include <code>UXTH</code> (16-bit), <code>UXTW</code> (32-bit), and <code>UXTX</code> (64-bit).
</li>

<li>