[llvm] [IPO] Prevent removal of some convergent attr (PR #134863)

[Matt Arsenault via llvm-commits]

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@@ -1864,6 +1864,19 @@ static bool InstrBreaksNonConvergent(Instruction &I,
          !SCCNodes.contains(CB->getCalledFunction());
 }
 
+static bool FunctionRequiresConvergence(const Function &F) {
+  for (auto &Use : F.uses()) {
+    CallBase *CB = dyn_cast<CallBase>(Use.getUser());
+    if (!CB)
+      return true;
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arsenm wrote:

Need to check if the use is the callee operand 

https://github.com/llvm/llvm-project/pull/134863