[clang] [llvm] [HLSL] Implement the `faceforward` intrinsic (PR #135878)

[Kaitlin Peng via llvm-commits]

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@@ -126,6 +126,24 @@ template <typename T> constexpr vector<T, 4> lit_impl(T NDotL, T NDotH, T M) {
   return Result;
 }
 
+template <typename T> constexpr T faceforward_impl(T N, T I, T Ng) {
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kmpeng wrote:

You're right. Removed vector implementation

https://github.com/llvm/llvm-project/pull/135878