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

[Artem Belevich via llvm-commits]

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@@ -747,6 +754,13 @@ def SELP_f16x2rr :
               [(set Int32Regs:$dst,
                     (select Int1Regs:$p, (v2f16 Int32Regs:$a), (v2f16 Int32Regs:$b)))]>;
 
+def SELP_i16x2rr :
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Artem-B wrote:

Needs sm90/ptx80 predicates?

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