Fix an unused variable warning.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179931 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -90,6 +90,7 @@ struct SLPVectorizer : public FunctionPass {
 
       // Vectorize trees that end at stores.
       if (unsigned count = collectStores(BB, R)) {
+        (void)count;
         DEBUG(dbgs()<<"SLP: Found " << count << " stores to vectorize.\n");
         BBChanged |= vectorizeStoreChains(R);
       }