[llvm-branch-commits] [llvm][IR] Extend BranchWeightMetadata to track provenance of weights (PR #86609)

[Matthias Braun via llvm-branch-commits]

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@@ -5196,7 +5198,11 @@ void SwitchInstProfUpdateWrapper::init() {
   if (!ProfileData)
     return;
 
-  if (ProfileData->getNumOperands() != SI.getNumSuccessors() + 1) {
+  // FIXME: This check belongs in ProfDataUtils. Its almost equivalent to
+  // getValidBranchWeightMDNode(), but the need to use llvm_unreachable
+  // makes them slightly different.
+  if (ProfileData->getNumOperands() !=
+      SI.getNumSuccessors() + getBranchWeightOffset(ProfileData)) {
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MatzeB wrote:

This seems simple enough to do something about it? Could for example add a `getNumBranchWeights(<profile_data>)` API so this can become `getNumBranchWeights(ProfileData) != SI.getNumSuccessors()`?

https://github.com/llvm/llvm-project/pull/86609