[llvm] [NVPTX] Make i16x2 a native type and add supported vec instructions (PR #65432)

[Artem Belevich via llvm-commits]

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@@ -149,12 +150,13 @@ static bool IsPTXVectorType(MVT VT) {
   }
 }
 
-static bool Isv2f16Orv2bf16Type(EVT VT) {
-  return (VT == MVT::v2f16 || VT == MVT::v2bf16);
+static bool Isv2f16Orv2bf16Orv2i16Type(EVT VT) {
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Artem-B wrote:

Ah, we already have that helper. Move it upwards and use it for the comparisons above.

Maybe rename it to something less cumbersome. `Isv2x16Type` ?

https://github.com/llvm/llvm-project/pull/65432