[llvm] [RFC][IR] InstructionListener: per-function instruction removal/RAUW notifications (PR #193198)

[Pankaj Dwivedi via llvm-commits]

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@@ -112,6 +114,29 @@ class LLVM_ABI Function : public GlobalObject, public ilist_node<Function> {
 
   friend class SymbolTableListTraits<Function>;
 
+  friend class InstructionListener;
+  SmallVector<InstructionListener *, 0> InstructionListeners;
+
+  void addInstructionListener(InstructionListener *L);
+  void removeInstructionListener(InstructionListener *L);
+
+public:
+  bool hasInstructionListeners() const { return !InstructionListeners.empty(); }
+
+  void notifyInstructionRemoved(Instruction *I) {
+    if (hasInstructionListeners())
+      notifyInstructionRemovedImpl(I);
+  }
+
+  void notifyInstructionRAUW(Instruction *Old, Value *New) {
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PankajDwivedi-25 wrote:

sure, thanks.

https://github.com/llvm/llvm-project/pull/193198