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

[Deric Cheung via llvm-commits]

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@@ -359,18 +359,21 @@ class OpLowerer {
     return lowerToBindAndAnnotateHandle(F);
   }
 
-  Error replaceSplitDoubleCallUsages(CallInst *Intrin, CallInst *Op) {
+  Error replaceExtractElementTypeOfCallUsages(CallInst *Intrin, CallInst *Op) {
     for (Use &U : make_early_inc_range(Intrin->uses())) {
       if (auto *EVI = dyn_cast<ExtractValueInst>(U.getUser())) {
 
         if (EVI->getNumIndices() != 1)
-          return createStringError(std::errc::invalid_argument,
-                                   "Splitdouble has only 2 elements");
+          return createStringError(
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Icohedron wrote:

Should there even be an error if there are non-`extractvalue` instructions using the result?
The function name I chose (`replaceExtractElementTypeOfCallUsages`) implies it will just change the type of `extractelement` instructions that use the result of the call.

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