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

[via llvm-commits]

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@@ -540,6 +540,48 @@ void StoreInst::dump() const {
   dump(dbgs());
   dbgs() << "\n";
 }
+#endif // NDEBUG
+
+Value *ReturnInst::create(Value *RetVal, Instruction *InsertBefore,
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vporpo wrote:

Ah yes, in this case we can return `RetunInst *`. In some other cases it gets folded by the IRBuilder, but not here.

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