diff --git a/docs/LangRef.html b/docs/LangRef.html
index 60dba67..e6cd794 100644
--- a/docs/LangRef.html
+++ b/docs/LangRef.html
@@ -101,6 +101,8 @@
         <ol>
           <li><a href="#i_returnaddress">'<tt>llvm.returnaddress</tt>' Intrinsic</a></li>
           <li><a href="#i_frameaddress">'<tt>llvm.frameaddress</tt>'   Intrinsic</a></li>
+          <li><a href="#i_readport">'<tt>llvm.readport</tt>'   Intrinsic</a></li>
+          <li><a href="#i_writeport">'<tt>llvm.writeport</tt>'   Intrinsic</a></li>
         </ol>
       </li>
       <li><a href="#int_libc">Standard C Library Intrinsics</a>
@@ -1996,6 +1998,95 @@
 </p>
 </div>
 
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+  <a name="i_readport">'<tt>llvm.readport</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+  call sbyte  (ushort address)* %llvm.readport(ushort &lt;address&gt;)
+  call ubyte  (ushort address)* %llvm.readport(ushort &lt;address&gt;)
+  call short  (ushort address)* %llvm.readport(ushort &lt;address&gt;)
+  call ushort (ushort address)* %llvm.readport(ushort &lt;address&gt;)
+  call int    (ushort address)* %llvm.readport(ushort &lt;address&gt;)
+  call uint   (ushort address)* %llvm.readport(ushort &lt;address&gt;)
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>llvm.readport</tt>' intrinsic reads data from the specified I/O port.
+</p>
+
+<h5>Arguments:</h5>
+
+<p>
+The argument to this intrinsic indicates the I/O address from which to read
+the data.  The address is in the I/O address namespace; it is not a memory
+location.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+The '<tt>llvm.readport</tt>' intrinsic reads data from the I/O port specified
+by <i>address</i> and returns the value.  The address and return value must
+be integers, but the size is dependent upon the platform upon which the
+program is code generated.  For example, on x86, the address must be a
+ushort, and the return value must be 8, 16, or 32 bits.
+</p>
+
+</div>
+
+<!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection">
+  <a name="i_writeport">'<tt>llvm.writeport</tt>' Intrinsic</a>
+</div>
+
+<div class="doc_text">
+
+<h5>Syntax:</h5>
+<pre>
+  call void (ushort address, sbyte value)* %llvm.writeport(ushort &lt;address&gt;, sbyte &lt;value&gt;)
+  call void (ushort address, ubyte value)* %llvm.writeport(ushort &lt;address&gt;, ubyte &lt;value&gt;)
+  call void (ushort address, short value)* %llvm.writeport(ushort &lt;address&gt;, short &lt;value&gt;)
+  call void (ushort address, ushort value)* %llvm.writeport(ushort &lt;address&gt;, ushort &lt;value&gt;)
+  call void (ushort address, int value)* %llvm.writeport(ushort &lt;address&gt;, int &lt;value&gt;)
+  call void (ushort address, uint value)* %llvm.writeport(ushort &lt;address&gt;, uint &lt;value&gt;)
+</pre>
+
+<h5>Overview:</h5>
+
+<p>
+The '<tt>llvm.writeport</tt>' intrinsic writes data to the specified I/O port.
+</p>
+
+<h5>Arguments:</h5>
+
+<p>
+The first argument to this intrinsic indicates the I/O address to which data
+should be written.  The address is in the I/O address namespace; it is not a
+memory location.
+</p>
+
+<p>
+The second argument is the value to write to the I/O port.
+</p>
+
+<h5>Semantics:</h5>
+
+<p>
+The '<tt>llvm.writeport</tt>' intrinsic writes <i>value</i> to the I/O port
+specified by <i>address</i>.  The address and value must be integers, but the
+size is dependent upon the platform upon which the program is code generated.
+For example, on x86, the address must be a ushort, and the value written must
+be 8, 16, or 32 bits in length.
+</p>
+
+</div>
 
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 <div class="doc_subsection">