[llvm] [NVPTX] Cleanup and document nvvm.fabs intrinsics, adding f16 support (PR #135644)

[Artem Belevich via llvm-commits]

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@@ -226,14 +226,17 @@ class RegTyInfo<ValueType ty, NVPTXRegClass rc, Operand imm, SDNode imm_node,
   int Size = ty.Size;
 }
 
-def I16RT : RegTyInfo<i16, Int16Regs, i16imm, imm>;
-def I32RT : RegTyInfo<i32, Int32Regs, i32imm, imm>;
-def I64RT : RegTyInfo<i64, Int64Regs, i64imm, imm>;
-
-def F32RT : RegTyInfo<f32, Float32Regs, f32imm, fpimm>;
-def F64RT : RegTyInfo<f64, Float64Regs, f64imm, fpimm>;
-def F16RT : RegTyInfo<f16, Int16Regs, f16imm, fpimm, supports_imm = 0>;
-def BF16RT : RegTyInfo<bf16, Int16Regs, bf16imm, fpimm, supports_imm = 0>;
+def I16RT    : RegTyInfo<i16, Int16Regs, i16imm, imm>;
+def I32RT    : RegTyInfo<i32, Int32Regs, i32imm, imm>;
+def I64RT    : RegTyInfo<i64, Int64Regs, i64imm, imm>;
+
+def F32RT    : RegTyInfo<f32, Float32Regs, f32imm, fpimm>;
+def F64RT    : RegTyInfo<f64, Float64Regs, f64imm, fpimm>;
+def F16RT    : RegTyInfo<f16, Int16Regs, f16imm, fpimm, supports_imm = 0>;
+def BF16RT   : RegTyInfo<bf16, Int16Regs, bf16imm, fpimm, supports_imm = 0>;
+
+def F16X2RT  : RegTyInfo<v2f16, Int32Regs, ?, ?, supports_imm = 0>;
+def BF16X2RT : RegTyInfo<v2bf16, Int32Regs, ?, ?, supports_imm = 0>;
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Artem-B wrote:

Interesting. I never thought of passing `?` as an argument. That can indeed be convenient in some cases.

https://github.com/llvm/llvm-project/pull/135644