[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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@@ -21,6 +21,7 @@
 #include "clang/AST/Type.h"
 #include "clang/AST/TypeLoc.h"
 #include "clang/Basic/Builtins.h"
+#include "clang/Basic/DiagnosticParse.h"
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inbelic wrote:

```suggestion
```

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