[SystemZ] Fix argument type of tdc instruction.

[Kai]

Summary

The DAG node for the Test Data Class is defined using i64 as the second parameter.
However, the code to lower is_fpclass uses i32 as type. This only works because no
type check is generated in the DAG matcher.
This PR changes the type of the mask constant to i64.

[uweigand]

LGTM, thanks!

llvm/lib/Target/SystemZ/SystemZISelLowering.cpp

SDValue SystemZTargetLowering::lowerIS_FPCLASS(SDValue Op,
   if (Check & fcPosSubnormal)
     TDCMask |= SystemZ::TDCMASK_SUBNORMAL_PLUS;
   if (Check & fcNegSubnormal)
     TDCMask |= SystemZ::TDCMASK_SUBNORMAL_MINUS;
   if (Check & fcPosZero)
     TDCMask |= SystemZ::TDCMASK_ZERO_PLUS;
   if (Check & fcNegZero)
     TDCMask |= SystemZ::TDCMASK_ZERO_MINUS;
-  SDValue TDCMaskV = DAG.getConstant(TDCMask, DL, MVT::i32);
+  SDValue TDCMaskV = DAG.getConstant(TDCMask, DL, MVT::i64);
 
   SDValue Intr = DAG.getNode(SystemZISD::TDC, DL, ResultVT, Arg, TDCMaskV);
   return getCCResult(DAG, Intr);
 }
 
 SDValue SystemZTargetLowering::LowerOperation(SDValue Op,
                                               SelectionDAG &DAG) const {
   switch (Op.getOpcode()) {