[llvm] [LLVM][NVPTX]Add BF16 vector instruction and fix lowering rules (PR #69415)

[Artem Belevich via llvm-commits]

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@@ -755,7 +769,7 @@ NVPTXTargetLowering::NVPTXTargetLowering(const NVPTXTargetMachine &TM,
   setOperationAction(ISD::FROUND, MVT::v2bf16, Expand);
   setOperationAction(ISD::FROUND, MVT::f32, Custom);
   setOperationAction(ISD::FROUND, MVT::f64, Custom);
-
+  AddPromotedToType(ISD::FROUND, MVT::bf16, MVT::f32);
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Artem-B wrote:

Same here -- keep `setOperationAction(ISD::FROUND, MVT::f16, Promote)` and `AddPromotedToType` together.

https://github.com/llvm/llvm-project/pull/69415