[llvm] [OPT] Search whole BB for convergence token. (PR #112728)

[Sameer Sahasrabuddhe via llvm-commits]

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@@ -180,6 +180,19 @@ namespace {
     }
   };
 
+  IntrinsicInst *getConevrgenceEntryIfAny(BasicBlock &BB) {
+    auto *I = BB.getFirstNonPHI();
+    while (I) {
+      if (auto *IntrinsicCall = dyn_cast<IntrinsicInst>(I)) {
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ssahasra wrote:

This should dyn_cast to `ConvergenceControlInst`, and then check with `isEntry()`.

https://llvm.org/docs/doxygen/classllvm_1_1ConvergenceControlInst.html

https://github.com/llvm/llvm-project/pull/112728