Aliasing chains cleanups: update langref, add check into verifier


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48685 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/LangRef.html b/docs/LangRef.html
index 41128c3..096acf2 100644
--- a/docs/LangRef.html
+++ b/docs/LangRef.html
@@ -763,8 +763,8 @@
 </div>
 <div class="doc_text">
   <p>Aliases act as "second name" for the aliasee value (which can be either
-  function or global variable or bitcast of global value). Aliases may have an
-  optional <a href="#linkage">linkage type</a>, and an
+  function, global variable, another alias or bitcast of global value). Aliases
+  may have an optional <a href="#linkage">linkage type</a>, and an
   optional <a href="#visibility">visibility style</a>.</p>
 
   <h5>Syntax:</h5>