[NVPTX] Report fatal error on empty argument type.

llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp

for (unsigned i = 0, e = theArgs.size(); i != e; ++i, ++idx, ++InsIdx) {
     Type *Ty = argTypes[i];
 
     if (theArgs[i]->use_empty()) {
       // argument is dead
       if (Ty->isAggregateType() || Ty->isIntegerTy(128)) {
         SmallVector<EVT, 16> vtparts;
 
         ComputePTXValueVTs(*this, DAG.getDataLayout(), Ty, vtparts);
-        assert(vtparts.size() > 0 && "empty aggregate type not expected");
+        if (vtparts.empty())
+          report_fatal_error("Empty parameter types are not supported");
+
         for (unsigned parti = 0, parte = vtparts.size(); parti != parte;
              ++parti) {
           InVals.push_back(DAG.getNode(ISD::UNDEF, dl, Ins[InsIdx].VT));
           ++InsIdx;
         }
         if (vtparts.size() > 0)
           --InsIdx;
         continue;
for (unsigned i = 0, e = theArgs.size(); i != e; ++i, ++idx, ++InsIdx) {
     if (!PAL.hasParamAttr(i, Attribute::ByVal)) {
       bool aggregateIsPacked = false;
       if (StructType *STy = dyn_cast<StructType>(Ty))
         aggregateIsPacked = STy->isPacked();
 
       SmallVector<EVT, 16> VTs;
       SmallVector<uint64_t, 16> Offsets;
       ComputePTXValueVTs(*this, DL, Ty, VTs, &Offsets, 0);
-      assert(VTs.size() > 0 && "Unexpected empty type.");
+      if (VTs.empty())
+        report_fatal_error("Empty parameter types are not supported");
+
       auto VectorInfo =
           VectorizePTXValueVTs(VTs, Offsets, DL.getABITypeAlign(Ty));
 
       SDValue Arg = getParamSymbol(DAG, idx, PtrVT);
       int VecIdx = -1; // Index of the first element of the current vector.
       for (unsigned parti = 0, parte = VTs.size(); parti != parte; ++parti) {
         if (VectorInfo[parti] & PVF_FIRST) {
           assert(VecIdx == -1 && "Orphaned vector.");

llvm/test/CodeGen/NVPTX/empty-type.ll

+; RUN: not --crash llc < %s -march=nvptx -mcpu=sm_20 2>&1 | FileCheck %s
+
+%struct.A = type { [0 x float] }
+%struct.B = type { i32, i32 }
+
+; CHECK: ERROR: Empty parameter types are not supported
+define void @kernel(%struct.A %a, %struct.B %b) {
+entry:
+  ret void
+}