Index: include/llvm/CodeGen/SelectionDAG.h
===================================================================
--- include/llvm/CodeGen/SelectionDAG.h
+++ include/llvm/CodeGen/SelectionDAG.h
@@ -471,7 +471,9 @@
     return Root;
   }
 
+#ifndef NDEBUG
   void VerifyDAGDiverence();
+#endif
 
   /// This iterates over the nodes in the SelectionDAG, folding
   /// certain types of nodes together, or eliminating superfluous nodes.  The
Index: lib/CodeGen/SelectionDAG/SelectionDAG.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -7955,6 +7955,7 @@
   }
 }
 
+#ifndef NDEBUG
 void SelectionDAG::VerifyDAGDiverence()
 {
   std::vector<SDNode*> TopoOrder;
@@ -7981,6 +7982,7 @@
            "Divergence bit inconsistency detected\n");
   }
 }
+#endif
 
 
 /// ReplaceAllUsesOfValuesWith - Replace any uses of From with To, leaving
Index: lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -714,8 +714,10 @@
   int BlockNumber = -1;
   (void)BlockNumber;
   bool MatchFilterBB = false; (void)MatchFilterBB;
+#ifndef NDEBUG
   TargetTransformInfo &TTI =
       getAnalysis<TargetTransformInfoWrapperPass>().getTTI(*FuncInfo->Fn);
+#endif
 
   // Pre-type legalization allow creation of any node types.
   CurDAG->NewNodesMustHaveLegalTypes = false;
@@ -750,8 +752,10 @@
     CurDAG->Combine(BeforeLegalizeTypes, AA, OptLevel);
   }
 
+#ifndef NDEBUG
   if (TTI.hasBranchDivergence())
     CurDAG->VerifyDAGDiverence();
+#endif
 
   LLVM_DEBUG(dbgs() << "Optimized lowered selection DAG: "
                     << printMBBReference(*FuncInfo->MBB) << " '" << BlockName
@@ -770,8 +774,10 @@
     Changed = CurDAG->LegalizeTypes();
   }
 
+#ifndef NDEBUG
   if (TTI.hasBranchDivergence())
     CurDAG->VerifyDAGDiverence();
+#endif
 
   LLVM_DEBUG(dbgs() << "Type-legalized selection DAG: "
                     << printMBBReference(*FuncInfo->MBB) << " '" << BlockName
@@ -792,8 +798,10 @@
       CurDAG->Combine(AfterLegalizeTypes, AA, OptLevel);
     }
 
+#ifndef NDEBUG
     if (TTI.hasBranchDivergence())
       CurDAG->VerifyDAGDiverence();
+#endif
 
     LLVM_DEBUG(dbgs() << "Optimized type-legalized selection DAG: "
                       << printMBBReference(*FuncInfo->MBB) << " '" << BlockName
@@ -839,8 +847,10 @@
                       << "'\n";
                CurDAG->dump());
 
+#ifndef NDEBUG
     if (TTI.hasBranchDivergence())
       CurDAG->VerifyDAGDiverence();
+#endif
   }
 
   if (ViewLegalizeDAGs && MatchFilterBB)
@@ -852,8 +862,10 @@
     CurDAG->Legalize();
   }
 
+#ifndef NDEBUG
   if (TTI.hasBranchDivergence())
     CurDAG->VerifyDAGDiverence();
+#endif
 
   LLVM_DEBUG(dbgs() << "Legalized selection DAG: "
                     << printMBBReference(*FuncInfo->MBB) << " '" << BlockName
@@ -870,8 +882,10 @@
     CurDAG->Combine(AfterLegalizeDAG, AA, OptLevel);
   }
 
+#ifndef NDEBUG
   if (TTI.hasBranchDivergence())
     CurDAG->VerifyDAGDiverence();
+#endif
 
   LLVM_DEBUG(dbgs() << "Optimized legalized selection DAG: "
                     << printMBBReference(*FuncInfo->MBB) << " '" << BlockName