[clang] [clang][HLSL] Add sign intrinsic part 3 (PR #101989)

[Farzon Lotfi via cfe-commits]

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@@ -4737,6 +4737,12 @@ def HLSLRSqrt : LangBuiltin<"HLSL_LANG"> {
   let Prototype = "void(...)";
 }
 
+def HLSLSign : LangBuiltin<"HLSL_LANG"> {
+  let Spellings = ["__builtin_hlsl_elementwise_sign"];
+  let Attributes = [NoThrow, Const];
+  let Prototype = "int(...)";
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farzonl wrote:

This is not correct Since we don't use `CustomTypeChecking` int will apply scalar integer rules. Since there is no way to specify int vector and int scalar we ussually just go with void so that no rules are applied.

https://github.com/llvm/llvm-project/pull/101989