[clang] [HLSL] Implement support for HLSL intrinsic - select (PR #107129)

[S. Bharadwaj Yadavalli via cfe-commits]

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@@ -1545,6 +1605,30 @@ bool SemaHLSL::CheckBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall) {
     break;
   }
   case Builtin::BI__builtin_hlsl_elementwise_saturate:
+  case Builtin::BI__builtin_hlsl_select: {
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bharadwajy wrote:

This addition splits the existing common case code for `BI__builtin_hlsl_elemetwise_saturate` and `BI__builtin_hlsl_elemetwise_rcp` - and would result in incorrect behavior for `BI__builtin_hlsl_elemetwise_saturate`. 

https://github.com/llvm/llvm-project/pull/107129