[NVPTX] Allow more argument integer types, such as i256 and i96 (#154824)

The refactoring of ComputePTXValueVTs in #154476 caused the complier to
no longer crash when lowering i256 and i96. This has caused a few tests
to unexpectedly pass.

Update these tests and tweak how we emit parameter declarations to
correctly lower these types.

Author: AlexMaclean

llvm/lib/Target/NVPTX/NVPTXUtilities.h

@@ -82,14 +82,16 @@ inline unsigned promoteScalarArgumentSize(unsigned size) {
     return 32;
   if (size <= 64)
     return 64;
+  if (size <= 128)
+    return 128;
   return size;
 }
 
 bool shouldEmitPTXNoReturn(const Value *V, const TargetMachine &TM);
 
 inline bool shouldPassAsArray(Type *Ty) {
   return Ty->isAggregateType() || Ty->isVectorTy() ||
-         Ty->getScalarSizeInBits() == 128 || Ty->isHalfTy() || Ty->isBFloatTy();
+         Ty->getScalarSizeInBits() >= 128 || Ty->isHalfTy() || Ty->isBFloatTy();
 }
 
 namespace NVPTX {

llvm/test/CodeGen/Generic/add-with-overflow-128.ll

@@ -1,8 +1,5 @@
 ; RUN: llc < %s
 
-; NVPTX fails to LowerFormalArguments for arg type i96
-; the arg byte size must be one of the {16, 8, 4, 2}
-; XFAIL: target=nvptx{{.*}}
 
 @ok = internal constant [4 x i8] c"%d\0A\00"
 @no = internal constant [4 x i8] c"no\0A\00"

llvm/test/CodeGen/Generic/icmp-illegal.ll

@@ -1,9 +1,5 @@
 ; RUN: llc < %s | FileCheck %s
 
-; NVPTX fails to LowerFormalArguments for arg size > i128
-; the arg byte size must be one of the {16, 8, 4, 2}
-; XFAIL: target=nvptx{{.*}}
-
 ; CHECK-LABEL: test_ult
 define i1 @test_ult(i256 %a) nounwind {
   %1 = icmp ult i256 %a, -6432394258550908438