[clang] [HLSL] Implement the dst HLSL Function (PR #133828)

[via cfe-commits]

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@@ -174,6 +174,31 @@ const inline float distance(__detail::HLSL_FIXED_VECTOR<float, N> X,
                             __detail::HLSL_FIXED_VECTOR<float, N> Y) {
   return __detail::distance_vec_impl(X, Y);
 }
+//===----------------------------------------------------------------------===//
+// dst builtins
+//===----------------------------------------------------------------------===//
+
+/// \fn fvector dst( fvector, fvector)
+/// \brief Returns the length of a vector
+/// \param Src0 [in] The first vector contain {_, d*d, d*d, _}
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metkarpoonam wrote:

The src0 provides the squared distance components (d * d) and is assumed to be the vector (ignored, d*d, d*d, ignored)

[https://github.com/MicrosoftDocs/win32/blob/docs/desktop-src//direct3dhlsl/dst---vs.md](url)

https://github.com/llvm/llvm-project/pull/133828