Hi folks. I want to instrument store instructions selectively to sanitize their target operands.
I need to
- First, identify instructions that access specific memory address at the LLVM IR and tag those store instructions
- Second, pass tags to the LLVM ARM backend and instrument store instructions at the Machine IR.
In the second step, it’s currently infeasible to tag instructions by neither Instruction metadata nor Instruction debuginfo.
- Instruction metadata will be removed when lowering LLVM IR to SelectionDAG.
- Debuginfo is const value which require no modification.
Another method is to replace store instructions in LLVM IR with LLVM intrinsic functions, and recover intrinsic functions with machine-specific store instructions at the ARM backend. However, it involves selecting the proper machine store instructions which may be tedious and error-prone.
Is there any other method to reach my goal?
Please correct me if anything I stated was wrong. Thank you in advance.