[clang] [llvm] Adding splitdouble HLSL function (PR #109331)

[Farzon Lotfi via cfe-commits]

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@@ -18901,6 +18901,160 @@ case Builtin::BI__builtin_hlsl_elementwise_isinf: {
         CGM.getHLSLRuntime().getRadiansIntrinsic(), ArrayRef<Value *>{Op0},
         nullptr, "hlsl.radians");
   }
+  // This should only be called when targeting DXIL
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farzonl wrote:

This comment seems old and maybe should be moved to line 18921.  SPIRV  implementation is on 18952.

https://github.com/llvm/llvm-project/pull/109331