How to propagate an information about an Instr. from IR to MachineInstr

Hello,

My objective is to duplicate some identified instructions for “fault tolerance” purpose,
and for that, I plugged my pass after the register allocation to avoid the SSA form.
So actually, what I want to do is to mark those instructions I want to duplicate at IR level and propagate that mark until MachineInstr level where the duplication is done.
By mark I mean any information that can help me to find out the instructions I have already identified earlier.
Is there any way to do so?

Thank you in advance

Thierno Barry
http://thiernobarry.fr/