[llvm] [NVPTX] Improve support for {ex2,lg2}.approx (PR #120519)

[Princeton Ferro via llvm-commits]

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@@ -1193,6 +1206,10 @@ defm FNEG_H: F2_Support_Half<"neg", fneg>;
 
 defm FSQRT : F2<"sqrt.rn", fsqrt>;
 
+defm FEXP2 : F1<"ex2.approx", fexp2>;
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Prince781 wrote:

Good catch. And I've added support for `ex2.approx.{f16,f16x2,bf16,bf16x2}` variants.

https://github.com/llvm/llvm-project/pull/120519