[llvm] [NVPTX] Add Volta Atomic SequentiallyConsistent Load and Store Operations (PR #98551)

[Artem Belevich via llvm-commits]

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@@ -82,6 +83,36 @@ inline unsigned promoteScalarArgumentSize(unsigned size) {
 bool shouldEmitPTXNoReturn(const Value *V, const TargetMachine &TM);
 
 bool Isv2x16VT(EVT VT);
+
+namespace NVPTX {
+
+inline char const *toCString(Ordering Order) {
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Artem-B wrote:

Nit. I'd change the name to better reflect the purpose. E.g. `OrderingToString` and, maybe, change the return type to a  `std::string`.

Functions returning values are also much easier to reason about, without worrying about the lifetimes and ownership of stuff pointed to by the returned pointer. 

https://github.com/llvm/llvm-project/pull/98551