Index: llvm/trunk/lib/Analysis/InstructionSimplify.cpp
===================================================================
--- llvm/trunk/lib/Analysis/InstructionSimplify.cpp
+++ llvm/trunk/lib/Analysis/InstructionSimplify.cpp
@@ -1376,8 +1376,7 @@
   // If all valid bits in the shift amount are known zero, the first operand is
   // unchanged.
   unsigned NumValidShiftBits = Log2_32_Ceil(BitWidth);
-  APInt ShiftAmountMask = APInt::getLowBitsSet(BitWidth, NumValidShiftBits);
-  if ((KnownZero & ShiftAmountMask) == ShiftAmountMask)
+  if (KnownZero.countTrailingOnes() >= NumValidShiftBits)
     return Op0;
 
   return nullptr;
@@ -3372,7 +3371,7 @@
       APInt LHSKnownOne(BitWidth, 0);
       computeKnownBits(LHS, LHSKnownZero, LHSKnownOne, Q.DL, /*Depth=*/0, Q.AC,
                        Q.CxtI, Q.DT);
-      if (((LHSKnownZero & *RHSVal) != 0) || ((LHSKnownOne & ~(*RHSVal)) != 0))
+      if (LHSKnownZero.intersects(*RHSVal) || !LHSKnownOne.isSubsetOf(*RHSVal))
         return Pred == ICmpInst::ICMP_EQ ? ConstantInt::getFalse(ITy)
                                          : ConstantInt::getTrue(ITy);
     }
Index: llvm/trunk/lib/Analysis/ValueTracking.cpp
===================================================================
--- llvm/trunk/lib/Analysis/ValueTracking.cpp
+++ llvm/trunk/lib/Analysis/ValueTracking.cpp
@@ -1934,12 +1934,12 @@
       // The sign bit of X is set.  If some other bit is set then X is not equal
       // to INT_MIN.
       computeKnownBits(X, KnownZero, KnownOne, Depth, Q);
-      if ((KnownOne & Mask) != 0)
+      if (KnownOne.intersects(Mask))
         return true;
       // The sign bit of Y is set.  If some other bit is set then Y is not equal
       // to INT_MIN.
       computeKnownBits(Y, KnownZero, KnownOne, Depth, Q);
-      if ((KnownOne & Mask) != 0)
+      if (KnownOne.intersects(Mask))
         return true;
     }
 
@@ -2056,7 +2056,7 @@
                        const Query &Q) {
   APInt KnownZero(Mask.getBitWidth(), 0), KnownOne(Mask.getBitWidth(), 0);
   computeKnownBits(V, KnownZero, KnownOne, Depth, Q);
-  return (KnownZero & Mask) == Mask;
+  return Mask.isSubsetOf(KnownZero);
 }
 
 /// For vector constants, loop over the elements and find the constant with the
@@ -4289,7 +4289,7 @@
         APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
         computeKnownBits(X, KnownZero, KnownOne, DL, Depth + 1, AC, CxtI, DT);
 
-        if ((KnownZero & *CA) == *CA && (KnownZero & *CB) == *CB)
+        if (CA->isSubsetOf(KnownZero) && CB->isSubsetOf(KnownZero))
           return true;
       }
 
Index: llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
===================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -1393,7 +1393,7 @@
   // zero, this value is constant.
   // FIXME: This should be in InstSimplify because we're replacing an
   // instruction with a constant.
-  if ((Mask & KnownZero) == Mask) {
+  if (Mask.isSubsetOf(KnownZero)) {
     auto *C = ConstantInt::get(IT, APInt(BitWidth, NumMaskBits));
     return IC.replaceInstUsesWith(II, C);
   }
Index: llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
===================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineSimplifyDemanded.cpp
@@ -453,11 +453,11 @@
 
       // If we are known to be adding/subtracting zeros to every bit below
       // the highest demanded bit, we just return the other side.
-      if ((DemandedFromOps & RHSKnownZero) == DemandedFromOps)
+      if (DemandedFromOps.isSubsetOf(RHSKnownZero))
         return I->getOperand(0);
       // We can't do this with the LHS for subtraction.
       if (I->getOpcode() == Instruction::Add &&
-          (DemandedFromOps & LHSKnownZero) == DemandedFromOps)
+          DemandedFromOps.isSubsetOf(LHSKnownZero))
         return I->getOperand(1);
     }
 
Index: llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
+++ llvm/trunk/lib/Transforms/Utils/SimplifyCFG.cpp
@@ -4380,7 +4380,7 @@
   SmallVector<ConstantInt *, 8> DeadCases;
   for (auto &Case : SI->cases()) {
     APInt CaseVal = Case.getCaseValue()->getValue();
-    if ((CaseVal & KnownZero) != 0 || (CaseVal & KnownOne) != KnownOne ||
+    if (KnownZero.intersects(CaseVal) || !KnownOne.isSubsetOf(CaseVal) ||
         (CaseVal.getMinSignedBits() > MaxSignificantBitsInCond)) {
       DeadCases.push_back(Case.getCaseValue());
       DEBUG(dbgs() << "SimplifyCFG: switch case " << CaseVal << " is dead.\n");
Index: llvm/trunk/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
+++ llvm/trunk/lib/Transforms/Vectorize/LoadStoreVectorizer.cpp
@@ -331,8 +331,7 @@
     APInt KnownZero(BitWidth, 0);
     APInt KnownOne(BitWidth, 0);
     computeKnownBits(OpA, KnownZero, KnownOne, DL, 0, nullptr, OpA, &DT);
-    KnownZero &= ~APInt::getHighBitsSet(BitWidth, 1);
-    if (KnownZero != 0)
+    if (KnownZero.countTrailingZeros() < (BitWidth - 1))
       Safe = true;
   }