The MQT Compiler Collection: A Blueprint for a Future-Proof Quantum-Classical Compilation Framework

TL;DR

The paper introduces the MQT Compiler Collection, a comprehensive quantum-classical compilation framework based on MLIR, designed to handle complex algorithms and optimizations for future quantum computing hardware.

Contribution

It presents a novel MLIR-based architecture supporting full quantum-classical compilation, addressing limitations of previous quantum-first approaches.

Findings

Supports complex optimizations beyond gate cancellation

Provides a full compilation pipeline from high-level algorithms to hardware instructions

Is publicly available at https://github.com/munich-quantum-toolkit/core

Abstract

As the capabilities of quantum computing hardware continue to rise, algorithms that exploit them are becoming increasingly complex. These developments increase the need for sophisticated compilation frameworks that translate high-level algorithms into executable code. In the past, most solutions were built with a quantum-first approach and handled mostly pure quantum programs without classical elements such as structured control flow. However, developments in quantum algorithms, error correction, and optimization, as well as the integration into high-performance computing (HPC) environments, depend on such classical elements. As quantum-first approaches increasingly struggle to handle these concepts, classical-first approaches are becoming a promising alternative. In this work, we present the MQT Compiler Collection, a blueprint for a future-proof quantum-classical compilation framework built on the Multi-Level Intermediate Representation (MLIR). After years of experience with the quantum-first approach and its shortcomings, we propose a framework that embraces core MLIR concepts to support the full compilation pipeline from high-level algorithms to hardware-specific instructions. The proposed architecture is designed from the ground up to support complex optimizations beyond, e.g., simple gate cancellation. It is publicly available at https://github.com/munich-quantum-toolkit/core.