[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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@@ -10623,7 +10623,7 @@ def err_second_argument_to_cwsc_not_pointer : Error<
   "second argument to __builtin_call_with_static_chain must be of pointer type">;
 
 def err_vector_incorrect_num_elements : Error<
-  "%select{too many|too few}0 elements in vector %select{initialization|operand}3 (expected %1 elements, have %2)">;
+  "%select{too many|too few|incorrect number of}0 elements in vector %select{initialization|operand}3 (expected %1 elements, have %2)">;
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Icohedron wrote:

I made a new commit ([d2b315a](https://github.com/llvm/llvm-project/pull/125319/commits/d2b315a24f850c6115675ee99c804873f19a8f40)) that creates a new diag message specifically for AddUint64, as per your suggestion (which I can't seem to find anymore?).
Is this better?

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