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

[Deric Cheung via cfe-commits]

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+; RUN: not opt -S -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s 2>&1 | FileCheck %s
+
+; DXIL operation UAddc only supports i32. Other integer types are unsupported.
+; CHECK: in function uaddc_i16
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Icohedron wrote:

LLVM ERROR is not output there.

The full error message is: `error: <unknown>:0:0: in function uaddc_i16 i16 (i16, i16): Cannot create UAddc operation: Invalid overload type`

This is similar to the way other directx error tests were written, such as [cos](https://github.com/llvm/llvm-project/blob/main/llvm/test/CodeGen/DirectX/cos_error.ll)

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