[clang] [HLSL] Overloads for `lerp` with a scalar weight (PR #137877)

[Farzon Lotfi via cfe-commits]

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@@ -277,6 +277,12 @@ constexpr bool4 isinf(double4 V) { return isinf((float4)V); }
 // lerp builtins overloads
 //===----------------------------------------------------------------------===//
 
+template <typename T, uint N>
+constexpr __detail::enable_if_t<(N > 1 && N <= 4), vector<T, N>>
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farzonl wrote:

I don't think compat overload is the right place for this. Seems like we might want to keep this around past 202x.

https://github.com/llvm/llvm-project/pull/137877