[llvm] [Coroutines] properly update CallGraph in CoroSplit (PR #107935)

[Yuxuan Chen via llvm-commits]

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@@ -2080,12 +2080,13 @@ splitCoroutine(Function &F, SmallVectorImpl<Function *> &Clones,
   return Shape;
 }
 
-static void updateCallGraphAfterCoroutineSplit(
+static LazyCallGraph::SCC &updateCallGraphAfterCoroutineSplit(
     LazyCallGraph::Node &N, const coro::Shape &Shape,
     const SmallVectorImpl<Function *> &Clones, LazyCallGraph::SCC &C,
     LazyCallGraph &CG, CGSCCAnalysisManager &AM, CGSCCUpdateResult &UR,
     FunctionAnalysisManager &FAM) {
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yuxuanchen1997 wrote:

@ChuanqiXu9 I am reverting this suggestion for now. We can do a refactor to change all `updateCGAndAnalysisManagerFor(Function|CGSCC)?Pass` usage once we decide on a new design. 

https://github.com/llvm/llvm-project/pull/107935