add mlir python bindings poc for qasm-to-qco pipeline

CMakeLists.txt

@@ -120,6 +120,12 @@ endif()
 
 cmake_dependent_option(BUILD_MQT_CORE_QIR_RUNNER "Build the QIR runner of the MQT Core project" ON
                        "BUILD_MQT_CORE_MLIR" OFF)
+cmake_dependent_option(
+  BUILD_MQT_CORE_MLIR_PYTHON
+  "Build Python bindings for the MQT MLIR compiler collection (requires MLIR_ENABLE_BINDINGS_PYTHON=ON)"
+  OFF
+  "BUILD_MQT_CORE_MLIR"
+  OFF)
 
 # add main library code
 add_subdirectory(src)
@@ -143,6 +149,7 @@ endif()
 
 if(BUILD_MQT_CORE_MLIR)
   add_subdirectory(mlir)
+  add_subdirectory(poc)
 
   # copy generated MLIR documentation
   add_custom_command(

mlir/CMakeLists.txt

@@ -40,6 +40,17 @@ add_subdirectory(include)
 add_subdirectory(lib)
 add_subdirectory(tools)
 
+if(BUILD_MQT_CORE_MLIR_PYTHON)
+  if(NOT MLIR_ENABLE_BINDINGS_PYTHON)
+    message(FATAL_ERROR "BUILD_MQT_CORE_MLIR_PYTHON requires MLIR to be built with "
+                        "MLIR_ENABLE_BINDINGS_PYTHON=ON. Re-build MLIR with that flag set.")
+  endif()
+  include(AddMLIRPython)
+  include(MLIRDetectPythonEnv)
+  mlir_configure_python_dev_packages()
+  add_subdirectory(python)
+endif()
+
 # add test code
 if(BUILD_MQT_CORE_TESTS)
   add_subdirectory(unittests)

mlir/include/mlir/CAPI/Dialects.h

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+ * Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * Licensed under the MIT License
+ */
+
+#pragma once
+
+#include "mlir-c/IR.h"
+#include "mlir-c/Support.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+MLIR_DECLARE_CAPI_DIALECT_REGISTRATION(QC, qc);
+MLIR_DECLARE_CAPI_DIALECT_REGISTRATION(QCO, qco);
+
+/** Registers and loads all MQT MLIR dialects into a context. */
+MLIR_CAPI_EXPORTED void mqtMlirRegisterAllDialects(MlirContext context);
+
+/** Registers all MQT MLIR passes into the global registry. */
+MLIR_CAPI_EXPORTED void mqtMlirRegisterAllPasses(void);
+
+#ifdef __cplusplus
+}
+#endif

mlir/lib/CAPI/CMakeLists.txt

@@ -0,0 +1,30 @@
+# Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+# Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+# All rights reserved.
+#
+# SPDX-License-Identifier: MIT
+#
+# Licensed under the MIT License
+
+add_mlir_public_c_api_library(
+  MQTMLIRCoreDialectsCAPI
+  Dialects.cpp
+  ADDITIONAL_HEADER_DIRS
+  ${MQT_MLIR_SOURCE_INCLUDE_DIR}/mlir/CAPI
+  ENABLE_AGGREGATION
+  LINK_LIBS
+  PUBLIC
+  MLIRIR
+  MLIRSupport
+  MLIRQCDialect
+  MLIRQCODialect
+  MLIRQTensorDialect
+  MLIRArithDialect
+  MLIRFuncDialect
+  MLIRMemRefDialect
+  MLIRSCFDialect
+  MLIRQCTransforms
+  MLIRQCOTransforms
+  MLIRQCToQCO)
+
+mqt_mlir_target_use_project_options(MQTMLIRCoreDialectsCAPI)

mlir/lib/CAPI/Dialects.cpp

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+ * Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * Licensed under the MIT License
+ */
+
+#include "mlir/CAPI/Dialects.h"
+
+#include "mlir-c/IR.h"
+#include "mlir/CAPI/IR.h"
+#include "mlir/CAPI/Registration.h"
+#include "mlir/Conversion/QCToQCO/QCToQCO.h"
+#include "mlir/Dialect/QC/IR/QCDialect.h"
+#include "mlir/Dialect/QC/Transforms/Passes.h"
+#include "mlir/Dialect/QCO/IR/QCODialect.h"
+#include "mlir/Dialect/QCO/Transforms/Passes.h" // NOLINT(misc-include-cleaner)
+#include "mlir/Dialect/QTensor/IR/QTensorDialect.h"
+
+#include <mlir/Dialect/Arith/IR/Arith.h>
+#include <mlir/Dialect/Func/IR/FuncOps.h>
+#include <mlir/Dialect/MemRef/IR/MemRef.h>
+#include <mlir/Dialect/SCF/IR/SCF.h>
+#include <mlir/IR/DialectRegistry.h>
+
+MLIR_DEFINE_CAPI_DIALECT_REGISTRATION(QC, qc, ::mlir::qc::QCDialect)
+MLIR_DEFINE_CAPI_DIALECT_REGISTRATION(QCO, qco, ::mlir::qco::QCODialect)
+
+void mqtMlirRegisterAllDialects(MlirContext context) {
+  mlir::DialectRegistry registry;
+  registry.insert<mlir::qc::QCDialect, mlir::qco::QCODialect,
+                  mlir::qtensor::QTensorDialect, mlir::arith::ArithDialect,
+                  mlir::func::FuncDialect, mlir::memref::MemRefDialect,
+                  mlir::scf::SCFDialect>();
+  unwrap(context)->appendDialectRegistry(registry);
+  unwrap(context)->loadAllAvailableDialects();
+}
+
+void mqtMlirRegisterAllPasses() {
+  mlir::qc::registerQCPasses();
+  mlir::qco::registerQCOPasses();
+  mlir::registerQCToQCOPasses();
+}

mlir/lib/CMakeLists.txt

@@ -10,3 +10,7 @@ add_subdirectory(Conversion)
 add_subdirectory(Compiler)
 add_subdirectory(Dialect)
 add_subdirectory(Support)
+
+if(BUILD_MQT_CORE_MLIR_PYTHON)
+  add_subdirectory(CAPI)
+endif()

mlir/python/CMakeLists.txt

@@ -0,0 +1,72 @@
+# Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+# Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+# All rights reserved.
+#
+# SPDX-License-Identifier: MIT
+#
+# Licensed under the MIT License
+
+# Disable versioned soname — causes duplication in Python wheels.
+set(CMAKE_PLATFORM_NO_VERSIONED_SONAME ON)
+
+set(MQT_MLIR_PYTHON_ROOT_DIR "${CMAKE_CURRENT_SOURCE_DIR}/mqt/core/mlir")
+set(MQT_MLIR_PYTHON_PACKAGES_DIR "${CMAKE_CURRENT_BINARY_DIR}/python_packages")
+
+# ##################################################################################################
+# Sources
+# ##################################################################################################
+
+declare_mlir_python_sources(MQTCoreMLIRPythonSources ROOT_DIR "${MQT_MLIR_PYTHON_ROOT_DIR}" SOURCES
+                            __init__.py _pipeline.py)
+
+declare_mlir_python_sources(MQTCoreMLIRPythonExtensions)
+
+# ##################################################################################################
+# Extension module
+# ##################################################################################################
+
+declare_mlir_python_extension(
+  MQTCoreMLIRPythonExtensions.Main
+  MODULE_NAME
+  _mqtCoreMlir
+  ADD_TO_PARENT
+  MQTCoreMLIRPythonExtensions
+  SOURCES
+  MQTCoreMLIRModule.cpp
+  EMBED_CAPI_LINK_LIBS
+  MQTMLIRCoreDialectsCAPI
+  MLIRQCTranslation
+  MLIRSupportMQT
+  PRIVATE_LINK_LIBS
+  LLVMSupport
+  MQT::CoreIR)
+
+# ##################################################################################################
+# Aggregate and install
+# ##################################################################################################
+
+set(_source_components MQTCoreMLIRPythonSources MQTCoreMLIRPythonExtensions)
+
+add_mlir_python_common_capi_library(
+  MQTCoreMLIRAggregateCAPI
+  INSTALL_COMPONENT
+  MQTCoreMLIRPythonModules
+  INSTALL_DESTINATION
+  python_packages/mqt/core/mlir/_mlir_libs
+  OUTPUT_DIRECTORY
+  "${MQT_MLIR_PYTHON_PACKAGES_DIR}/mqt/core/mlir/_mlir_libs"
+  RELATIVE_INSTALL_ROOT
+  "../../../.."
+  DECLARED_SOURCES
+  ${_source_components})
+
+add_mlir_python_modules(
+  MQTCoreMLIRPythonModules
+  ROOT_PREFIX
+  "${MQT_MLIR_PYTHON_PACKAGES_DIR}/mqt/core/mlir"
+  INSTALL_PREFIX
+  "python_packages/mqt/core/mlir"
+  DECLARED_SOURCES
+  ${_source_components}
+  COMMON_CAPI_LINK_LIBS
+  MQTCoreMLIRAggregateCAPI)

mlir/python/MQTCoreMLIRModule.cpp

@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+ * Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+ * All rights reserved.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * Licensed under the MIT License
+ */
+
+#include "mlir-c/IR.h"
+#include "mlir/Bindings/Python/NanobindAdaptors.h" // NOLINT(misc-include-cleaner)
+#include "mlir/CAPI/Dialects.h"
+#include "mlir/Conversion/QCToQCO/QCToQCO.h" // NOLINT(misc-include-cleaner)
+#include "mlir/Dialect/QC/Translation/TranslateQuantumComputationToQC.h" // NOLINT(misc-include-cleaner)
+#include "mlir/Support/Passes.h" // NOLINT(misc-include-cleaner)
+#include "qasm3/Importer.hpp"
+
+#include <llvm/Support/raw_ostream.h>   // NOLINT(misc-include-cleaner)
+#include <mlir/IR/BuiltinOps.h>         // NOLINT(misc-include-cleaner)
+#include <mlir/IR/MLIRContext.h>        // NOLINT(misc-include-cleaner)
+#include <mlir/Pass/PassManager.h>      // NOLINT(misc-include-cleaner)
+#include <mlir/Support/LogicalResult.h> // NOLINT(misc-include-cleaner)
+
+#include <stdexcept> // NOLINT(misc-include-cleaner)
+#include <string>    // NOLINT(misc-include-cleaner)
+
+namespace nb = nanobind; // NOLINT(misc-unused-alias-decls)
+
+// NOLINTNEXTLINE(misc-use-internal-linkage,readability-identifier-naming,readability-named-parameter)
+NB_MODULE(_mqtCoreMlir, m) {
+  mqtMlirRegisterAllPasses();
+
+  m.doc() = "MQT Core MLIR Python bindings";
+
+  auto registerDialects = [](MlirContext context) {
+    mqtMlirRegisterAllDialects(context);
+  };
+  m.def("register_dialects", registerDialects, nb::arg("context"),
+        "Register and load QC, QCO, QTensor, and dependent MLIR dialects.");
+
+  m.def(
+      "qasm_to_qco",
+      [](const std::string& qasm) -> std::string {
+        auto qc = qasm3::Importer::imports(qasm);
+
+        mlir::MLIRContext ctx;
+        MlirContext cCtx{&ctx};
+        mqtMlirRegisterAllDialects(cCtx);
+
+        auto module = mlir::translateQuantumComputationToQC(&ctx, qc);
+        if (!module) {
+          throw std::runtime_error("failed to translate circuit to QC MLIR");
+        }
+
+        mlir::PassManager pm(&ctx);
+        populateQCCleanupPipeline(pm);
+        pm.addPass(mlir::createQCToQCO());
+        if (mlir::failed(pm.run(*module))) {
+          throw std::runtime_error("qc-to-qco conversion failed");
+        }
+
+        std::string out;
+        llvm::raw_string_ostream os(out);
+        module->print(os);
+        return out;
+      },
+      nb::arg("qasm"),
+      "Run the full (py:qasm) -> (mlir:qc) -> (mlir:qco) pipeline.");
+}

mlir/python/mqt/core/mlir/__init__.py

@@ -0,0 +1,16 @@
+# Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+# Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+# All rights reserved.
+#
+# SPDX-License-Identifier: MIT
+#
+# Licensed under the MIT License
+
+"""Python bindings for the MQT MLIR compiler collection."""
+
+from __future__ import annotations
+
+from ._mlir_libs._mqtCoreMlir import qasm_to_qco, register_dialects
+from ._pipeline import compile_qc_to_qco, make_context
+
+__all__ = ["compile_qc_to_qco", "make_context", "qasm_to_qco", "register_dialects"]

mlir/python/mqt/core/mlir/_pipeline.py

@@ -0,0 +1,39 @@
+# Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+# Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+# All rights reserved.
+#
+# SPDX-License-Identifier: MIT
+#
+# Licensed under the MIT License
+
+"""High-level pipeline helpers built on top of the MLIR Python bindings."""
+
+from __future__ import annotations
+
+from mlir.ir import Context, Module
+from mlir.passmanager import PassManager
+
+from ._mlir_libs._mqtCoreMlir import register_dialects
+
+
+def make_context() -> Context:
+    """Return an MLIRContext with all MQT dialects registered and loaded."""
+    ctx = Context()
+    register_dialects(ctx)
+    return ctx
+
+
+def compile_qc_to_qco(mlir_text: str) -> str:
+    """Run the qc-to-qco conversion pass on an MLIR module given as text.
+
+    Args:
+        mlir_text: MLIR module in the QC dialect, as a string.
+
+    Returns:
+        The resulting QCO dialect MLIR module as a string.
+    """
+    with make_context() as ctx:
+        module = Module.parse(mlir_text, ctx)
+        pm = PassManager.parse("builtin.module(qc-to-qco)", ctx)
+        pm.run(module.operation)
+        return str(module)

poc/CMakeLists.txt

@@ -0,0 +1,27 @@
+# Copyright (c) 2023 - 2026 Chair for Design Automation, TUM
+# Copyright (c) 2025 - 2026 Munich Quantum Software Company GmbH
+# All rights reserved.
+#
+# SPDX-License-Identifier: MIT
+#
+# Licensed under the MIT License
+
+add_executable(poc-test-pipeline test_pipeline.cpp)
+
+target_link_libraries(
+  poc-test-pipeline
+  PRIVATE MLIRQCDialect
+          MLIRQCODialect
+          MLIRQTensorDialect
+          MLIRArithDialect
+          MLIRFuncDialect
+          MLIRMemRefDialect
+          MLIRSCFDialect
+          MLIRQCTranslation
+          MLIRQCToQCO
+          MLIRSupportMQT
+          MLIRPass
+          MQT::CoreIR
+          MQT::CoreQASM)
+
+mqt_mlir_target_use_project_options(poc-test-pipeline)