[llvm] [ctx_prof] Handle `select` and its `step` instrumentation (PR #109185)

[David Li via llvm-commits]

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@@ -324,12 +341,34 @@ class ProfileAnnotator final {
     PB.addEntryCount(Counters[0]);
 
     for (auto &BB : F) {
+      const auto &BBInfo = getBBInfo(BB);
+      if (BBInfo.getCount() > 0) {
+        for (auto &I : BB) {
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david-xl wrote:

put this into a helper function?

https://github.com/llvm/llvm-project/pull/109185