switch from pointer equality comparison to MDNode::getMostGenericTBAA 
when merging two TBAA tags, pointed out by Nuno.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171627 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LICM.cpp b/lib/Transforms/Scalar/LICM.cpp
index 9335363..dc6bef7 100644
--- a/lib/Transforms/Scalar/LICM.cpp
+++ b/lib/Transforms/Scalar/LICM.cpp
@@ -46,6 +46,7 @@
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Metadata.h"
 #include "llvm/Support/CFG.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
@@ -816,10 +817,11 @@
       if (LoopUses.empty()) {
         // On the first load/store, just take its TBAA tag.
         TBAATag = Use->getMetadata(LLVMContext::MD_tbaa);
-      } else if (TBAATag && TBAATag != Use->getMetadata(LLVMContext::MD_tbaa)) {
-        TBAATag = 0;
+      } else if (TBAATag) {
+        TBAATag = MDNode::getMostGenericTBAA(TBAATag,
+                                       Use->getMetadata(LLVMContext::MD_tbaa));
       }
-    
+      
       LoopUses.push_back(Use);
     }
   }