[clang] [llvm] [HLSL] [DXIL] Implement the AddUint64 HLSL function and the UAddc DXIL op (PR #127137)

[Finn Plummer via cfe-commits]

================
@@ -19445,6 +19445,70 @@ Value *CodeGenFunction::EmitHLSLBuiltinExpr(unsigned BuiltinID,
     return nullptr;
 
   switch (BuiltinID) {
+  case Builtin::BI__builtin_hlsl_adduint64: {
+    Value *OpA = EmitScalarExpr(E->getArg(0));
----------------
inbelic wrote:

Forwarding: https://github.com/llvm/llvm-project/pull/125319#discussion_r1939753976

https://github.com/llvm/llvm-project/pull/127137