[llvm] [LoopUnroll] Consider convergence control tokens when unrolling (PR #91715)

[Eli Friedman via llvm-commits]

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@@ -111,11 +112,22 @@ void CodeMetrics::collectEphemeralValues(
   completeEphemeralValues(Visited, Worklist, EphValues);
 }
 
+static bool isUsedOutsideOfLoop(const Instruction &I, const Loop &L) {
+  for (const auto *U : I.users()) {
+    if (auto *I = dyn_cast<Instruction>(U)) {
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efriedma-quic wrote:

All users of Instructions are Instructions; just `cast<>`.

https://github.com/llvm/llvm-project/pull/91715