[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:

> I noted that the signature is actually very similar to LLVM's updateCGAndAnalysisManagerForPass() signature. Perhaps it is better to be consistent with that? https://llvm.org/doxygen/CGSCCPassManager_8cpp.html#a490117b63072462d035a6933fdb94c1f

Perhaps. Or perhaps the answer is to rewrite `updateCGAndAnalysisManagerForPass`. I really don't like the current semantics. I will see what I can do in another patch. 

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