Expand the bullet item about i128 support and APInt usage in codegen.

llvm-svn: 52007

llvm/docs/ReleaseNotes.html

@@ -195,7 +195,12 @@ faster:</p>
 
 <ul>
 <li>MemOperand in the code generator: describe me!.</li>
-<li>i128 support and APInt through most of codegen.</li>
+<li>Target-independent codegen infastructure now uses LLVM's APInt class for
+    handling integer values, which allow it to support integer types larger
+    than 64 bits. Note that support for such types is also dependent on
+    target-specific support. Use of APInt is also a step toward support for
+    non-power-of-2 integer sizes.</li>
+<li>Support for 128-bit integers on X86-64.</li>
 <li>Several compile time speedups for code with large basic blocks.</li>
 </ul>