[llvm] [ProfCheck] Add utility to get a MDNode for unknown branch weights (PR #180389)

[Aiden Grossman via llvm-commits]

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@@ -289,6 +289,18 @@ void llvm::setExplicitlyUnknownBranchWeightsIfProfiled(Instruction &I,
     setExplicitlyUnknownBranchWeights(I, PassName);
 }
 
+MDNode *llvm::getExplicitlyUnknownBranchWeightsIfProfiled(Function &F,
+                                                          StringRef PassName) {
+  if (std::optional<Function::ProfileCount> EC = F.getEntryCount();
+      !EC || EC->getCount() == 0)
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boomanaiden154 wrote:

Ack. I'm going to land this as-is. If we decide on some improvement here, we should do it in a follow up and uniformly to the other functions.

https://github.com/llvm/llvm-project/pull/180389