Quantum Constant Propagation (QCP)

Quantum Constant Propagation (QCP) implements a quantum equivalent to the classic constant propagation. It propagates the information about the initial state through the quantum circuit and uses the information made available at each gate to remove superfluous controls or even gates. The quantum state is split by entanglement groups and is only propagated until the entanglement becomes too complex. This ensures efficient running time of the optimization.

Build and Run

Prerequisites

For the project to clone and compile the following packages need to be installed: git, opam

Links to install the mentioned packages are listed below with their version used:

• git (2.34.1): https://git-scm.com/book/en/v2/Getting-Started-Installing-Git
• opam (2.1.2): https://opam.ocaml.org/doc/Install.html

Clone Repository

This repository contains submodule(s). Clone it with:

git clone --recursive git@github.com:i2-tum/qcp.git

Preparation

The building process of the project requires a functioning OCaml switch with several dependencies installed, for that run:

make ocaml   # this process takes a couple of minutes

Build

After the steps above, the project can be built either with dune build directly or with:

make build   # this should only take few seconds

Run

To run the tool on a single circuit, you can use the following command. You need to specify a configuration file that contains several settings for the optimization pass. Take a look at those located in configs. The tool accepts OpenQASM 2.0 input.

dune exec --no-build --action-stderr-on-success=must-be-empty -- qcprop -c configs/qcprop64.yml < examples/circ.qasm

Develop

The steps above install a bare minimum of required packages to compile the project. For the development of the tool, it is convenient to install additional packages by performing the following command. This enables auto-completion for OCaml files.

make devel