Correct the value of LowBits in srem and urem handling in

ComputeMaskedBits.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50692 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 9 insertions, 9 deletions

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 26d5548617..3e75f7b305 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -1560,7 +1560,7 @@ void SelectionDAG::ComputeMaskedBits(SDOperand Op, const APInt &Mask,
     if (ConstantSDNode *Rem = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
       APInt RA = Rem->getAPIntValue();
       if (RA.isPowerOf2() || (-RA).isPowerOf2()) {
-        APInt LowBits = RA.isStrictlyPositive() ? ((RA - 1) | RA) : ~RA;
+        APInt LowBits = RA.isStrictlyPositive() ? (RA - 1) : ~RA;
         APInt Mask2 = LowBits | APInt::getSignBit(BitWidth);
         ComputeMaskedBits(Op.getOperand(0), Mask2,KnownZero2,KnownOne2,Depth+1);
 
@@ -1581,8 +1581,8 @@ void SelectionDAG::ComputeMaskedBits(SDOperand Op, const APInt &Mask,
   case ISD::UREM: {
     if (ConstantSDNode *Rem = dyn_cast<ConstantSDNode>(Op.getOperand(1))) {
       APInt RA = Rem->getAPIntValue();
-      if (RA.isStrictlyPositive() && RA.isPowerOf2()) {
-        APInt LowBits = (RA - 1) | RA;
+      if (RA.isPowerOf2()) {
+        APInt LowBits = (RA - 1);
         APInt Mask2 = LowBits & Mask;
         KnownZero |= ~LowBits & Mask;
         ComputeMaskedBits(Op.getOperand(0), Mask2, KnownZero, KnownOne,Depth+1);
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 6b1da0d256..461d5fc780 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -965,7 +965,7 @@ void InstCombiner::ComputeMaskedBits(Value *V, const APInt &Mask,
     if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
       APInt RA = Rem->getValue();
       if (RA.isPowerOf2() || (-RA).isPowerOf2()) {
-        APInt LowBits = RA.isStrictlyPositive() ? ((RA - 1) | RA) : ~RA;
+        APInt LowBits = RA.isStrictlyPositive() ? (RA - 1) : ~RA;
         APInt Mask2 = LowBits | APInt::getSignBit(BitWidth);
         ComputeMaskedBits(I->getOperand(0), Mask2,KnownZero2,KnownOne2,Depth+1);
 
@@ -986,8 +986,8 @@ void InstCombiner::ComputeMaskedBits(Value *V, const APInt &Mask,
   case Instruction::URem: {
     if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
       APInt RA = Rem->getValue();
-      if (RA.isStrictlyPositive() && RA.isPowerOf2()) {
-        APInt LowBits = (RA - 1) | RA;
+      if (RA.isPowerOf2()) {
+        APInt LowBits = (RA - 1);
         APInt Mask2 = LowBits & Mask;
         KnownZero |= ~LowBits & Mask;
         ComputeMaskedBits(I->getOperand(0), Mask2, KnownZero, KnownOne,Depth+1);
@@ -1728,7 +1728,7 @@ bool InstCombiner::SimplifyDemandedBits(Value *V, APInt DemandedMask,
     if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
       APInt RA = Rem->getValue();
       if (RA.isPowerOf2() || (-RA).isPowerOf2()) {
-        APInt LowBits = RA.isStrictlyPositive() ? (RA - 1) | RA : ~RA;
+        APInt LowBits = RA.isStrictlyPositive() ? (RA - 1) : ~RA;
         APInt Mask2 = LowBits | APInt::getSignBit(BitWidth);
         if (SimplifyDemandedBits(I->getOperand(0), Mask2,
                                  LHSKnownZero, LHSKnownOne, Depth+1))
@@ -1749,8 +1749,8 @@ bool InstCombiner::SimplifyDemandedBits(Value *V, APInt DemandedMask,
   case Instruction::URem: {
     if (ConstantInt *Rem = dyn_cast<ConstantInt>(I->getOperand(1))) {
       APInt RA = Rem->getValue();
-      if (RA.isStrictlyPositive() && RA.isPowerOf2()) {
-        APInt LowBits = (RA - 1) | RA;
+      if (RA.isPowerOf2()) {
+        APInt LowBits = (RA - 1);
         APInt Mask2 = LowBits & DemandedMask;
         KnownZero |= ~LowBits & DemandedMask;
         if (SimplifyDemandedBits(I->getOperand(0), Mask2,