[llvm] [SandboxIR] Implement ReturnInst (PR #99784)

[Sriraman Tallam via llvm-commits]

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@@ -776,6 +812,8 @@ class Context {
   friend LoadInst; // For createLoadInst()
   StoreInst *createStoreInst(llvm::StoreInst *SI);
   friend StoreInst; // For createStoreInst()
+  ReturnInst *createReturnInst(llvm::ReturnInst *I);
+  friend ReturnInst; // For createReturnInst()
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tmsri wrote:

Why does OpaqueInst need to create Return Inst?  

https://github.com/llvm/llvm-project/pull/99784