[DAG] Use auto* for cast/dyn_cast results (style). NFC.

Author: RKSimon

llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp

@@ -2955,7 +2955,7 @@ bool TargetLowering::SimplifyDemandedBits(
     const SDNode *N = Op.getNode();
     for (SDNode *Op :
          llvm::make_range(SDNodeIterator::begin(N), SDNodeIterator::end(N))) {
-      if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op))
+      if (auto *C = dyn_cast<ConstantSDNode>(Op))
         if (C->isOpaque())
           return false;
     }
@@ -4657,7 +4657,7 @@ SDValue TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1,
         isa<LoadSDNode>(N0.getOperand(0)) &&
         N0.getOperand(0).getNode()->hasOneUse() &&
         isa<ConstantSDNode>(N0.getOperand(1))) {
-      LoadSDNode *Lod = cast<LoadSDNode>(N0.getOperand(0));
+      auto *Lod = cast<LoadSDNode>(N0.getOperand(0));
       APInt bestMask;
       unsigned bestWidth = 0, bestOffset = 0;
       if (Lod->isSimple() && Lod->isUnindexed() &&
@@ -5727,7 +5727,7 @@ TargetLowering::ParseConstraints(const DataLayout &DL,
       // The return value of the call is this value.  As such, there is no
       // corresponding argument.
       assert(!Call.getType()->isVoidTy() && "Bad inline asm!");
-      if (StructType *STy = dyn_cast<StructType>(Call.getType())) {
+      if (auto *STy = dyn_cast<StructType>(Call.getType())) {
         OpInfo.ConstraintVT =
             getSimpleValueType(DL, STy->getElementType(ResNo));
       } else {