implement and document support for CHECK-NOT


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82408 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/TestingGuide.html b/docs/TestingGuide.html
index f974363..9e4a40a 100644
--- a/docs/TestingGuide.html
+++ b/docs/TestingGuide.html
@@ -595,6 +595,36 @@
 </div>
 
 <!-- _______________________________________________________________________ -->
+<div class="doc_subsubsection"><a 
+name="FileCheck-CHECK-NOT">The "CHECK-NOT:" directive</a></div>
+
+<div class="doc_text">
+
+<p>The CHECK-NOT: directive is used to verify that a string doesn't occur
+between two matches (or the first matches and the beginning of the file).  For
+example, to verify that a load is removed by a transformation, a test like this
+can be used:</p>
+
+<div class="doc_code">
+<pre>
+define i8 @coerce_offset0(i32 %V, i32* %P) {
+  store i32 %V, i32* %P
+   
+  %P2 = bitcast i32* %P to i8*
+  %P3 = getelementptr i8* %P2, i32 2
+
+  %A = load i8* %P3
+  ret i8 %A
+; <b>CHECK:</b> @coerce_offset0
+; <b>CHECK-NOT:</b> load
+; <b>CHECK:</b> ret i8
+}
+</pre>
+</div>
+
+</div>
+
+<!-- _______________________________________________________________________ -->
 <div class="doc_subsection"><a name="dgvars">Variables and
 substitutions</a></div>
 <!-- _______________________________________________________________________ -->