[CUDA] Make empty parameter lists in nvptx function decls easier to read.

[jlebar]

Summary

Before:

.func  (.param .b32 func_retval0) _ZL21__nvvm_reflect_anchorv(

)
{

After:

.func  (.param .b32 func_retval0) _ZL21__nvvm_reflect_anchorv()
{

[bkramer]

One nit, looks good otherwise.

lib/Target/NVPTX/NVPTXAsmPrinter.cpp

1439 ↗

(On Diff #45798)

arg_empty()

[jlebar]

Address bkramer's review comment.

llvm/trunk/lib/Target/NVPTX/NVPTXAsmPrinter.cpp

void NVPTXAsmPrinter::emitFunctionParamList(const Function *F, raw_ostream &O) {
   const TargetLowering *TLI = nvptxSubtarget->getTargetLowering();
   Function::const_arg_iterator I, E;
   unsigned paramIndex = 0;
   bool first = true;
   bool isKernelFunc = llvm::isKernelFunction(*F);
   bool isABI = (nvptxSubtarget->getSmVersion() >= 20);
   MVT thePointerTy = TLI->getPointerTy(DL);
 
+  if (F->arg_empty()) {
+    O << "()\n";
+    return;
+  }
+
   O << "(\n";
 
   for (I = F->arg_begin(), E = F->arg_end(); I != E; ++I, paramIndex++) {
     Type *Ty = I->getType();
 
     if (!first)
       O << ",\n";