Add a couple very minor tweaks
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25359 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/ExtendingLLVM.html b/docs/ExtendingLLVM.html
index b86d561..419b7c6 100644
--- a/docs/ExtendingLLVM.html
+++ b/docs/ExtendingLLVM.html
@@ -26,7 +26,8 @@
<div class="doc_author">
<p>Written by <a href="http://misha.brukman.net">Misha Brukman</a>,
- Brad Jones, and <a href="http://nondot.org/sabre">Chris Lattner</a></p>
+ Brad Jones, Nate Begeman,
+ and <a href="http://nondot.org/sabre">Chris Lattner</a></p>
</div>
<!-- *********************************************************************** -->
@@ -123,7 +124,8 @@
code in all cases, just emit the expansion in <tt>visitCallInst</tt> in
<tt>Writer.cpp</tt>. If the intrinsic has some way to express it with GCC
(or any other compiler) extensions, it can be conditionally supported based on
-the compiler compiling the CBE output (see llvm.prefetch for an example).
+the compiler compiling the CBE output (see <tt>llvm.prefetch</tt> for an
+example).
Third, if the intrinsic really has no way to be lowered, just have the code
generator emit code that prints an error message and calls abort if executed.
</dd>
@@ -136,13 +138,14 @@
code, you will likely need to add support for your intrinsic there as well.
This is usually accomplished by adding a new node, and then teaching the
SelectionDAG code how to handle that node. To do this, follow the steps in
-the next section, Adding a new SelectionDAG node.</dd>
+the <a href="#sdnode">Adding a new SelectionDAG node</a> section.</dd>
<dl>
<dt>Once you have added the new node, add code to
<tt>SelectionDAG/SelectionDAGISel.cpp</tt> to recognize the intrinsic. In most
cases, the intrinsic will just be turned into the node you just added. For an
-example of this, see how <tt>visitIntrinsicCall</tt> handles Intrinsic::ctpop
+example of this, see how <tt>visitIntrinsicCall</tt> handles
+<tt>Intrinsic::ctpop_*</tt>.
</dt>
</div>
@@ -182,14 +185,15 @@
targets supported by the SelectionDAG framework will natively support the
new node. In this case, you must also add code in your node's case
statement in <tt>LegalizeOp</tt> to Expand your node into simpler, legal
- operations. The case for ISD::UREM for expanding a remainder into a
- multiply and a subtract is a good example.</li>
+ operations. The case for <tt>ISD::UREM</tt> for expanding a remainder into
+ a divide, multiply, and a subtract is a good example.</li>
<li><tt>lib/CodeGen/SelectionDAG/LegalizeDAG.cpp</tt>:
If targets may support the new node being added only at certain sizes, you
will also need to add code to your node's case statement in
<tt>LegalizeOp</tt> to Promote your node's operands to a larger size, and
perform the correct operation. You will also need to add code to
- <tt>PromoteOp</tt> to do this as well. For a good example, see ISD::BSWAP,
+ <tt>PromoteOp</tt> to do this as well. For a good example, see
+ <tt>ISD::BSWAP</tt>,
which promotes its operand to a wider size, performs the byteswap, and then
shifts the correct bytes right to emulate the narrower byteswap in the
wider type.</li>