[clang] Hlsl dst function (PR #133828)

[Damyan Pepper via cfe-commits]

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@@ -35,6 +35,12 @@ length_vec_impl(vector<T, N> X) {
 #endif
 }
 
+template <typename T>
+constexpr vector<T, 4> dst_impl(vector<T, 4> src0, vector<T, 4> src1) {
+  vector<T, 4> dest = {1, src0[1] * src1[1], src0[2], src1[3]};
+  return dest;
+}
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damyanp wrote:

It looks like this needs to be done across most of the tests.  I won't call out each one, but can you do a pass through to make sure this is following the naming conventions please?

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