[llvm] [SandboxIR] IR Tracker (PR #99238)

[Arthur Eubanks via llvm-commits]

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@@ -51,3 +51,14 @@ For example, for `sandboxir::User::setOperand(OpIdx, sandboxir::Value *Op)`:
 - We get the corresponding LLVM User: `llvm::User *LLVMU = cast<llvm::User>(Val)`
 - Next we get the corresponding LLVM Operand: `llvm::Value *LLVMOp = Op->Val`
 - Finally we modify `LLVMU`'s operand: `LLVMU->setOperand(OpIdx, LLVMOp)
+
+## IR Change Tracking
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aeubanks wrote:

mention that we don't support nested save/restore

https://github.com/llvm/llvm-project/pull/99238