[clang] [llvm] [HLSL] [DXIL] Implement the `AddUint64` HLSL function and the `UAddc` DXIL op (PR #125319)

[Finn Plummer via cfe-commits]

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@@ -230,6 +230,14 @@ static StructType *getSplitDoubleType(LLVMContext &Context) {
   return StructType::create({Int32Ty, Int32Ty}, "dx.types.splitdouble");
 }
 
+static StructType *getBinaryWithCarryType(LLVMContext &Context) {
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inbelic wrote:

This is maybe something that we could consider being generated from `DXIL.td`, alongside the other custom struct types. Maybe not for this pull request, but we can make a note here for the follow up pr: https://github.com/llvm/llvm-project/issues/113192

https://github.com/llvm/llvm-project/pull/125319