[clang] [llvm] [NVPTX] Add builtins and intrinsics for conversions of new FP types (PR #134345)

[Alex MacLean via cfe-commits]

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@@ -1548,6 +1548,45 @@ let TargetPrefix = "nvvm" in {
       Intrinsic<[llvm_v2f16_ty], [llvm_i16_ty], [IntrNoMem, IntrNoCallback]>;
   def int_nvvm_e5m2x2_to_f16x2_rn_relu : ClangBuiltin<"__nvvm_e5m2x2_to_f16x2_rn_relu">,
       Intrinsic<[llvm_v2f16_ty], [llvm_i16_ty], [IntrNoMem, IntrNoCallback]>;
+  
+  def int_nvvm_ff_to_e2m3x2_rn : ClangBuiltin<"__nvvm_ff_to_e2m3x2_rn">,
+      Intrinsic<[llvm_i16_ty], [llvm_float_ty, llvm_float_ty], [IntrNoMem, IntrNoCallback]>;
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AlexMaclean wrote:

Can all these intrinisics be made DefaultAttrsIntrinsics? 

https://github.com/llvm/llvm-project/pull/134345