diff --git a/include/llvm/CodeGen/SelectionDAGNodes.h b/include/llvm/CodeGen/SelectionDAGNodes.h
index 7567ecc..ef155d8 100644
--- a/include/llvm/CodeGen/SelectionDAGNodes.h
+++ b/include/llvm/CodeGen/SelectionDAGNodes.h
@@ -249,7 +249,14 @@
     // to them to be chained together for add and sub of arbitrarily large
     // values.
     ADDE, SUBE,
-    
+
+    // Overflow-aware nodes for arithmetic operations. These nodes take two
+    // operands: the normal lhs and rhs to the add. They produce two results:
+    // the normal result of the add, and a flag indicating whether an overflow
+    // occured. These nodes are generated from the llvm.[su]add.with.overflow
+    // intrinsics. They are lowered by target-dependent code.
+    SADDO, UADDO,
+
     // Simple binary floating point operators.
     FADD, FSUB, FMUL, FDIV, FREM,
 
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 61a04bf..d22a65d 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -5151,6 +5151,8 @@
   case ISD::CARRY_FALSE:         return "carry_false";
   case ISD::ADDC:        return "addc";
   case ISD::ADDE:        return "adde";
+  case ISD::SADDO:       return "saddo";
+  case ISD::UADDO:       return "uaddo";
   case ISD::SUBC:        return "subc";
   case ISD::SUBE:        return "sube";
   case ISD::SHL_PARTS:   return "shl_parts";