[clang] [llvm] [HLSL] Implement dot2add intrinsic (PR #131237)

[Sumit Agarwal via llvm-commits]

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@@ -175,6 +175,21 @@ const inline float distance(__detail::HLSL_FIXED_VECTOR<float, N> X,
   return __detail::distance_vec_impl(X, Y);
 }
 
+//===----------------------------------------------------------------------===//
+// dot2add builtins
----------------
sumitsays wrote:

The general pattern is to use `builtins` in this file for all other intrinsics. Is there any specific reason you think it should be `builtin` just for this intrinsic?

https://github.com/llvm/llvm-project/pull/131237