[llvm] [SandboxIR] Implement FenceInst (PR #105920)

[Sriraman Tallam via llvm-commits]

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@@ -575,6 +575,33 @@ void Instruction::dumpOS(raw_ostream &OS) const {
 }
 #endif // NDEBUG
 
+FenceInst *FenceInst::create(AtomicOrdering Ordering, BBIterator WhereIt,
+                             BasicBlock *WhereBB, Context &Ctx,
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tmsri wrote:

Why not use llvm::InsertPosition to define where to insert?  

https://github.com/llvm/llvm-project/pull/105920