[docs] Document a way to simplify names in bugpoint output

llvm-svn: 318257
diff --git a/llvm/docs/Bugpoint.rst b/llvm/docs/Bugpoint.rst
index 6bd7ff9..3327c02 100644
--- a/llvm/docs/Bugpoint.rst
+++ b/llvm/docs/Bugpoint.rst
@@ -151,6 +151,9 @@
   optimizations to be randomized and applied to the program. This process will
   repeat until a bug is found or the user kills ``bugpoint``.
 
+* ``bugpoint`` can produce IR which contains long names. To simplify the names,
+  run ``opt -strip -instnamer`` over the IR.
+
 What to do when bugpoint isn't enough
 =====================================