I wish to have a "reset" gate. This gate would have an effect to bring a qubit to the $\mid0\rangle$ state.
Clearly, such a gate is not unitary (and so I'm unable to find any reliable implementation in terms of universal gates).
Now for my particular needs, I need this ability to reset a qubit or a quantum register to that state so users can always start from $\mid0\rangle$. I'm making a small programming language that transpiles to QASM, and when a function is exited, I want all local (quantum) variables (qubits) reset to $\mid0\rangle$ so they can be reused. QASM reset instruction does not work on the real processor.
I think that something to this effect may be achieved with quantum phase estimation but I'm wondering if there is another way.