diff --git a/llvm/lib/Analysis/CFG.cpp b/llvm/lib/Analysis/CFG.cpp
index 44191f0..18b83d6 100644
--- a/llvm/lib/Analysis/CFG.cpp
+++ b/llvm/lib/Analysis/CFG.cpp
@@ -254,8 +254,8 @@
   }
 
   if (DT) {
-    if (DT->isReachableFromEntry(A->getParent()) !=
-        DT->isReachableFromEntry(B->getParent()))
+    if (DT->isReachableFromEntry(A->getParent()) &&
+        !DT->isReachableFromEntry(B->getParent()))
       return false;
     if (!ExclusionSet || ExclusionSet->empty()) {
       if (A->getParent() == &A->getParent()->getParent()->getEntryBlock() &&