✨ MLIR - Introduce Constant Propagation as optimization method

[LiRem101]

Problem Statement

Constant propagation is a tool that has been used successfully in classical optimization. There have also been proposals for this in the quantum realm. This is not yet implemented in mqt-core.

Proposed Solution

I would like to propose implementing quantum constant propagation in MLIR of mqt-core. Additionally, I'd like to expand the QCP with a classical constant propagation, in order to consider classical control flow alongside quantum control flow. This should provide the possibility to reduce the quantum resources needed in a quantum circuit.