GlobalISel: Don't hardcode varargs=false in resultsCompatible

[paquette]

LGTM

[arsenm]

6f5ddf67319b50664f3f5a4001723454696594b4

llvm/lib/CodeGen/GlobalISel/CallLowering.cpp

bool CallLowering::resultsCompatible(CallLoweringInfo &Info,
   const Function &F = MF.getFunction();
   CallingConv::ID CalleeCC = Info.CallConv;
   CallingConv::ID CallerCC = F.getCallingConv();
 
   if (CallerCC == CalleeCC)
     return true;
 
   SmallVector<CCValAssign, 16> ArgLocs1;
-  CCState CCInfo1(CalleeCC, false, MF, ArgLocs1, F.getContext());
+  CCState CCInfo1(CalleeCC, Info.IsVarArg, MF, ArgLocs1, F.getContext());
   if (!determineAssignments(CalleeAssigner, InArgs, CCInfo1))
     return false;
 
   SmallVector<CCValAssign, 16> ArgLocs2;
-  CCState CCInfo2(CallerCC, false, MF, ArgLocs2, F.getContext());
+  CCState CCInfo2(CallerCC, F.isVarArg(), MF, ArgLocs2, F.getContext());
   if (!determineAssignments(CallerAssigner, InArgs, CCInfo2))
     return false;
 
   // We need the argument locations to match up exactly. If there's more in
   // one than the other, then we are done.
   if (ArgLocs1.size() != ArgLocs2.size())
     return false;