diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 062b9d9..f7c1d06 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -2759,15 +2759,15 @@
   }
   // fold select C, 0, X -> ~C & X
   if (VT == VT0 && VT == MVT::i1 && N1C && N1C->isNullValue()) {
-    SDValue XORNode = DAG.getNode(ISD::XOR, VT, N0, DAG.getConstant(1, VT));
-    AddToWorkList(XORNode.getNode());
-    return DAG.getNode(ISD::AND, VT, XORNode, N2);
+    SDValue NOTNode = DAG.getNOT(N0, VT);
+    AddToWorkList(NOTNode.getNode());
+    return DAG.getNode(ISD::AND, VT, NOTNode, N2);
   }
   // fold select C, X, 1 -> ~C | X
   if (VT == VT0 && VT == MVT::i1 && N2C && N2C->getAPIntValue() == 1) {
-    SDValue XORNode = DAG.getNode(ISD::XOR, VT, N0, DAG.getConstant(1, VT));
-    AddToWorkList(XORNode.getNode());
-    return DAG.getNode(ISD::OR, VT, XORNode, N1);
+    SDValue NOTNode = DAG.getNOT(N0, VT);
+    AddToWorkList(NOTNode.getNode());
+    return DAG.getNode(ISD::OR, VT, NOTNode, N1);
   }
   // fold select C, X, 0 -> C & X
   // FIXME: this should check for C type == X type, not i1?
@@ -5574,8 +5574,7 @@
     if (N1C && N1C->isNullValue() && CC == ISD::SETGT) { 
       SDValue NegN0 = DAG.getNode(ISD::SUB, XType, DAG.getConstant(0, XType),
                                     N0);
-      SDValue NotN0 = DAG.getNode(ISD::XOR, XType, N0, 
-                                    DAG.getConstant(~0ULL, XType));
+      SDValue NotN0 = DAG.getNOT(N0, XType);
       return DAG.getNode(ISD::SRL, XType, 
                          DAG.getNode(ISD::AND, XType, NegN0, NotN0),
                          DAG.getConstant(XType.getSizeInBits()-1,
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 608dde2..10baccb 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -6318,7 +6318,7 @@
       SDValue Tmp3 = DAG.getConstant(1ULL << i, ShVT);
       Op = DAG.getNode(ISD::OR, VT, Op, DAG.getNode(ISD::SRL, VT, Op, Tmp3));
     }
-    Op = DAG.getNode(ISD::XOR, VT, Op, DAG.getConstant(~0ULL, VT));
+    Op = DAG.getNOT(Op, VT);
     return DAG.getNode(ISD::CTPOP, VT, Op);
   }
   case ISD::CTTZ: {
@@ -6327,9 +6327,7 @@
     // { return 32 - nlz(~x & (x-1)); }
     // see also http://www.hackersdelight.org/HDcode/ntz.cc
     MVT VT = Op.getValueType();
-    SDValue Tmp2 = DAG.getConstant(~0ULL, VT);
-    SDValue Tmp3 = DAG.getNode(ISD::AND, VT,
-                       DAG.getNode(ISD::XOR, VT, Op, Tmp2),
+    SDValue Tmp3 = DAG.getNode(ISD::AND, VT, DAG.getNOT(Op, VT),
                        DAG.getNode(ISD::SUB, VT, Op, DAG.getConstant(1, VT)));
     // If ISD::CTLZ is legal and CTPOP isn't, then do that instead.
     if (!TLI.isOperationLegal(ISD::CTPOP, VT) &&
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index e498647..a088560 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -816,6 +816,21 @@
                  getConstant(Imm, Op.getValueType()));
 }
 
+/// getNOT - Create a bitwise NOT operation as (XOR Val, -1).
+///
+SDValue SelectionDAG::getNOT(SDValue Val, MVT VT) {
+  SDValue NegOne;
+  if (VT.isVector()) {
+    MVT EltVT = VT.getVectorElementType();
+    SDValue NegOneElt = getConstant(EltVT.getIntegerVTBitMask(), EltVT);
+    std::vector<SDValue> NegOnes(VT.getVectorNumElements(), NegOneElt);
+    NegOne = getNode(ISD::BUILD_VECTOR, VT, &NegOnes[0], NegOnes.size());
+  } else
+    NegOne = getConstant(VT.getIntegerVTBitMask(), VT);
+
+  return getNode(ISD::XOR, VT, Val, NegOne);
+}
+
 SDValue SelectionDAG::getConstant(uint64_t Val, MVT VT, bool isT) {
   MVT EltVT = VT.isVector() ? VT.getVectorElementType() : VT;
   return getConstant(APInt(EltVT.getSizeInBits(), Val), VT, isT);
diff --git a/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 364a121..cd5df4f 100644
--- a/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -1798,39 +1798,39 @@
   if (N0.getValueType() == MVT::i1 && foldBooleans) {
     switch (Cond) {
     default: assert(0 && "Unknown integer setcc!");
-    case ISD::SETEQ:  // X == Y  -> (X^Y)^1
+    case ISD::SETEQ:  // X == Y  -> ~(X^Y)
       Temp = DAG.getNode(ISD::XOR, MVT::i1, N0, N1);
-      N0 = DAG.getNode(ISD::XOR, MVT::i1, Temp, DAG.getConstant(1, MVT::i1));
+      N0 = DAG.getNOT(Temp, MVT::i1);
       if (!DCI.isCalledByLegalizer())
         DCI.AddToWorklist(Temp.getNode());
       break;
     case ISD::SETNE:  // X != Y   -->  (X^Y)
       N0 = DAG.getNode(ISD::XOR, MVT::i1, N0, N1);
       break;
-    case ISD::SETGT:  // X >s Y   -->  X == 0 & Y == 1  -->  X^1 & Y
-    case ISD::SETULT: // X <u Y   -->  X == 0 & Y == 1  -->  X^1 & Y
-      Temp = DAG.getNode(ISD::XOR, MVT::i1, N0, DAG.getConstant(1, MVT::i1));
+    case ISD::SETGT:  // X >s Y   -->  X == 0 & Y == 1  -->  ~X & Y
+    case ISD::SETULT: // X <u Y   -->  X == 0 & Y == 1  -->  ~X & Y
+      Temp = DAG.getNOT(N0, MVT::i1);
       N0 = DAG.getNode(ISD::AND, MVT::i1, N1, Temp);
       if (!DCI.isCalledByLegalizer())
         DCI.AddToWorklist(Temp.getNode());
       break;
-    case ISD::SETLT:  // X <s Y   --> X == 1 & Y == 0  -->  Y^1 & X
-    case ISD::SETUGT: // X >u Y   --> X == 1 & Y == 0  -->  Y^1 & X
-      Temp = DAG.getNode(ISD::XOR, MVT::i1, N1, DAG.getConstant(1, MVT::i1));
+    case ISD::SETLT:  // X <s Y   --> X == 1 & Y == 0  -->  ~Y & X
+    case ISD::SETUGT: // X >u Y   --> X == 1 & Y == 0  -->  ~Y & X
+      Temp = DAG.getNOT(N1, MVT::i1);
       N0 = DAG.getNode(ISD::AND, MVT::i1, N0, Temp);
       if (!DCI.isCalledByLegalizer())
         DCI.AddToWorklist(Temp.getNode());
       break;
-    case ISD::SETULE: // X <=u Y  --> X == 0 | Y == 1  -->  X^1 | Y
-    case ISD::SETGE:  // X >=s Y  --> X == 0 | Y == 1  -->  X^1 | Y
-      Temp = DAG.getNode(ISD::XOR, MVT::i1, N0, DAG.getConstant(1, MVT::i1));
+    case ISD::SETULE: // X <=u Y  --> X == 0 | Y == 1  -->  ~X | Y
+    case ISD::SETGE:  // X >=s Y  --> X == 0 | Y == 1  -->  ~X | Y
+      Temp = DAG.getNOT(N0, MVT::i1);
       N0 = DAG.getNode(ISD::OR, MVT::i1, N1, Temp);
       if (!DCI.isCalledByLegalizer())
         DCI.AddToWorklist(Temp.getNode());
       break;
-    case ISD::SETUGE: // X >=u Y  --> X == 1 | Y == 0  -->  Y^1 | X
-    case ISD::SETLE:  // X <=s Y  --> X == 1 | Y == 0  -->  Y^1 | X
-      Temp = DAG.getNode(ISD::XOR, MVT::i1, N1, DAG.getConstant(1, MVT::i1));
+    case ISD::SETUGE: // X >=u Y  --> X == 1 | Y == 0  -->  ~Y | X
+    case ISD::SETLE:  // X <=s Y  --> X == 1 | Y == 0  -->  ~Y | X
+      Temp = DAG.getNOT(N1, MVT::i1);
       N0 = DAG.getNode(ISD::OR, MVT::i1, N0, Temp);
       break;
     }