⬆️ Update munich-quantum-toolkit/core from v3.9.1 to v3.10.0

.github/workflows/ci.yml

@@ -113,7 +113,7 @@ jobs:
     with:
       clang-version: 20
       files-changed-only: true
-      install-pkgs: "nanobind==2.15.0"
+      install-pkgs: "nanobind==3.0.1"
       setup-python: true
       cpp-linter-extra-args: "-std=c++20"
     permissions:

CHANGELOG.md

@@ -12,13 +12,24 @@ releases may include breaking changes.
 
 ### Changed
 
+- ⬆️ Update `mqt-core` to version 3.10.0 ([#995]) ([**@denialhaag**])
+- ⬆️ Update `nanobind` to version 3.0.1 ([#995]) ([**@denialhaag**])
+- 💥 Require Python 3.11 or newer ([#976]) ([**@denialhaag**])
+- 📦 Publish one split-mode `cp311-abi3` wheel for GIL-enabled CPython 3.11 and
+  newer ([#995]) ([**@denialhaag**])
+- 📦 Publish one `cp315-abi3t` wheel for free-threaded CPython 3.15 and newer
+  ([#995]) ([**@denialhaag**])
+- 💥 Raise the minimum Qiskit version from 1.1.0 to 2.1.0 ([#995])
+  ([**@denialhaag**])
+- ♻️ Own the circuit generators and DD gate matrices used by the command-line
+  interface, tests, and noise simulation ([#995]) ([**@denialhaag**])
+- ♻️ Normalize circuits with `QuantumComputation` member operations ([#995])
+  ([**@simon1hofmann**])
 - 💥 Drop support for x86 macOS and stop publishing the respective wheels
   ([#976]) ([**@denialhaag**])
 - ⬆️ Raise the macOS deployment target to 13.3 to enable `std::format` in libc++
   ([#976]) ([**@denialhaag**])
-- 💥 Require Python 3.11 or newer ([#976]) ([**@denialhaag**])
-- 🚚 Move recursive unitary construction from MQT Core to MQT DDSIM ([#975])
-  ([**@simon1hofmann**])
+- ♻️ Own recursive unitary construction ([#975]) ([**@simon1hofmann**])
 
 ## [2.5.0] - 2026-08-20
 
@@ -174,6 +185,7 @@ _📚 Refer to the [GitHub Release Notes] for previous changelogs._
 
 <!-- PR links -->
 
+[#995]: https://github.com/munich-quantum-toolkit/ddsim/pull/995
 [#976]: https://github.com/munich-quantum-toolkit/ddsim/pull/976
 [#975]: https://github.com/munich-quantum-toolkit/ddsim/pull/975
 [#966]: https://github.com/munich-quantum-toolkit/ddsim/pull/966

CMakeLists.txt

@@ -33,11 +33,6 @@ if(BUILD_MQT_DDSIM_BINDINGS)
       ON
       CACHE BOOL "Prevent multiple searches for Python and instead cache the results.")
 
-  if(DISABLE_GIL)
-    message(STATUS "Disabling Python GIL")
-    add_compile_definitions(Py_GIL_DISABLED)
-  endif()
-
   # top-level call to find Python
   find_package(Python 3.11 REQUIRED COMPONENTS Interpreter Development.Module
                                                ${SKBUILD_SABI_COMPONENT})

UPGRADING.md

@@ -6,16 +6,34 @@ of changes including minor and patch releases, please refer to the
 
 ## [Unreleased]
 
+This release updates the minimum required `mqt-core` version to 3.10.0.
+
 ### macOS support
 
 MQT DDSIM no longer supports x86 macOS. Use Apple silicon with macOS 13.3 or
 newer. The new deployment target enables `std::format` in libc++.
 
-### Python support
+### Qiskit 2.1 minimum
+
+The minimum Qiskit version increases from **1.1.0 to 2.1.0**, dropping support
+for all Qiskit 1.x releases and Qiskit 2.0. Upgrade Qiskit to 2.1.0 or newer.
+
+### Python 3.11 and Stable ABI wheels
 
 MQT DDSIM now requires Python 3.11 or newer. Upgrade the Python environment
 before installing this release.
 
+MQT DDSIM now publishes one `cp311-abi3` wheel for GIL-enabled CPython 3.11 and
+newer. Free-threaded support starts with CPython 3.15 in a separate
+`cp315-abi3t` wheel. MQT DDSIM no longer publishes free-threaded CPython 3.13 or
+3.14 wheels.
+
+This release updates `nanobind` to 3.0.1, which changes the `nanobind` ABI.
+
+The Python bindings depend on `nanobind-backend`, which supplies the
+interpreter-specific `nanobind` runtime. This dependency does not change the C++
+API or the Python import paths.
+
 ## [2.5.0]
 
 This release updates the minimum required `mqt-core` version to 3.9.0 and

apps/CMakeLists.txt

@@ -13,7 +13,7 @@ macro(ADD_SIM_EXECUTABLE appname)
 endmacro()
 
 add_sim_executable(simple cxxopts::cxxopts)
-target_link_libraries(mqt-ddsim-simple PRIVATE MQT::CoreAlgorithms)
+target_include_directories(mqt-ddsim-simple PRIVATE ${PROJECT_SOURCE_DIR}/src)
 
 if(Threads_FOUND)
   add_sim_executable(noise_aware cxxopts::cxxopts)

apps/simple.cpp

@@ -8,15 +8,13 @@
  * Licensed under the MIT License
  */
 
+#include "CircuitGenerators.hpp"
 #include "CircuitSimulator.hpp"
 #include "GroverSimulator.hpp"
 #include "HybridSchrodingerFeynmanSimulator.hpp"
 #include "ShorFastSimulator.hpp"
 #include "ShorSimulator.hpp"
 #include "Simulator.hpp"
-#include "algorithms/GHZState.hpp"
-#include "algorithms/Grover.hpp"
-#include "algorithms/QFT.hpp"
 #include "dd/Export.hpp"
 #include "ir/QuantumComputation.hpp"
 #include "qasm3/Importer.hpp"
@@ -135,8 +133,8 @@ int main(int argc, char** argv) { // NOLINT(bugprone-exception-escape)
     }
   } else if (vm.count("simulate_qft") > 0) {
     const unsigned int nQubits = vm["simulate_qft"].as<unsigned int>();
-    quantumComputation =
-        std::make_unique<qc::QuantumComputation>(qc::createQFT(nQubits));
+    quantumComputation = std::make_unique<qc::QuantumComputation>(
+        ddsim::detail::createQFT(nQubits));
     ddsim = std::make_unique<CircuitSimulator>(std::move(quantumComputation),
                                                approximationInfo, seed);
   } else if (vm.count("simulate_fast_shor") > 0) {
@@ -164,7 +162,7 @@ int main(int argc, char** argv) { // NOLINT(bugprone-exception-escape)
   } else if (vm.count("simulate_grover") > 0) {
     const unsigned int nQubits = vm["simulate_grover"].as<unsigned int>();
     quantumComputation = std::make_unique<qc::QuantumComputation>(
-        qc::createGrover(nQubits, seed));
+        ddsim::detail::createGrover(nQubits, seed));
     ddsim = std::make_unique<CircuitSimulator>(std::move(quantumComputation),
                                                approximationInfo, seed);
   } else if (vm.count("simulate_grover_emulated") > 0) {
@@ -175,8 +173,8 @@ int main(int argc, char** argv) { // NOLINT(bugprone-exception-escape)
         vm["simulate_grover_oracle_emulated"].as<std::string>(), seed);
   } else if (vm.count("simulate_ghz") > 0) {
     const unsigned int nQubits = vm["simulate_ghz"].as<unsigned int>();
-    quantumComputation =
-        std::make_unique<qc::QuantumComputation>(qc::createGHZState(nQubits));
+    quantumComputation = std::make_unique<qc::QuantumComputation>(
+        ddsim::detail::createGHZState(nQubits));
     ddsim = std::make_unique<CircuitSimulator>(std::move(quantumComputation),
                                                approximationInfo, seed);
   } else {

cmake/ExternalDependencies.cmake

@@ -33,11 +33,11 @@ if(BUILD_MQT_DDSIM_BINDINGS)
 endif()
 
 # cmake-format: off
-set(MQT_CORE_MINIMUM_VERSION 3.9.0
+set(MQT_CORE_MINIMUM_VERSION 3.10.0
     CACHE STRING "MQT Core minimum version")
-set(MQT_CORE_VERSION 3.9.1
+set(MQT_CORE_VERSION 3.10.0
     CACHE STRING "MQT Core version")
-set(MQT_CORE_REV "24ed6a2ec6a740d54a122be04b634c5ce8c289fd"
+set(MQT_CORE_REV "e9e2c959b3c81fda10ea8db34b908b638e61ba49"
     CACHE STRING "MQT Core identifier (tag, branch or commit hash)")
 set(MQT_CORE_REPO_OWNER "munich-quantum-toolkit"
     CACHE STRING "MQT Core repository owner (change when using a fork)")

include/DensityNode.hpp

@@ -182,6 +182,30 @@ struct dNode final : dd::NodeBase { // NOLINT(readability-identifier-naming)
   /// Getter for the terminal object
   static constexpr dNode* getTerminal() noexcept { return nullptr; }
 
+  /// Mark flag used for mark-and-sweep garbage collection.
+  static constexpr std::uint16_t MARK_FLAG = 0b10000U;
+
+  /// Check whether the node is marked as used.
+  [[nodiscard]] bool isMarked() const noexcept {
+    return (flags & MARK_FLAG) != 0U;
+  }
+
+  /// Mark the node as used.
+  void mark() noexcept { flags |= MARK_FLAG; }
+
+  /// Unmark the node.
+  void unmark() noexcept { flags &= static_cast<std::uint16_t>(~MARK_FLAG); }
+
+  /**
+   * @brief Check whether a pointer represents a terminal density node.
+   * @details Density nodes encode temporary state in the three least
+   * significant pointer bits. These bits do not make a terminal pointer
+   * non-terminal.
+   */
+  [[nodiscard]] static bool isTerminal(const dNode* p) noexcept {
+    return (reinterpret_cast<std::uintptr_t>(p) & (~7ULL)) == 0ULL;
+  }
+
   [[nodiscard]] [[maybe_unused]] static constexpr bool
   tempDensityMatrixFlagsEqual(const std::uint8_t a,
                               const std::uint8_t b) noexcept {

include/DensityUniqueTable.hpp

@@ -67,7 +67,7 @@ class DensityUniqueTable {
   // Only normalized nodes shall be stored.
   [[nodiscard]] dNode* lookup(dNode* p) {
     // there are unique terminal nodes
-    if (dd::NodeBase::isTerminal(p)) {
+    if (dNode::isTerminal(p)) {
       return p;
     }
 
@@ -98,7 +98,7 @@ class DensityUniqueTable {
   void clear();
 
 private:
-  using Bucket = dd::NodeBase*;
+  using Bucket = dNode*;
   using Table = std::vector<Bucket>;
 
   UniqueTableConfig cfg;
@@ -109,7 +109,7 @@ class DensityUniqueTable {
 
   [[nodiscard]] dNode* searchTable(dNode& p, const std::size_t& key) {
     const auto v = p.v;
-    auto* bucket = static_cast<dNode*>(tables[v][key]);
+    auto* bucket = tables[v][key];
     while (bucket != nullptr) {
       if (nodesAreEqual(p, *bucket)) {
         // Match found

include/HybridSchrodingerFeynmanSimulator.hpp

@@ -11,7 +11,6 @@
 #pragma once
 
 #include "CircuitSimulator.hpp"
-#include "circuit_optimizer/CircuitOptimizer.hpp"
 #include "dd/DDDefinitions.hpp"
 #include "dd/Node.hpp"
 #include "dd/Package.hpp"
@@ -38,9 +37,9 @@ class HybridSchrodingerFeynmanSimulator final : public CircuitSimulator {
       const std::size_t nthreads_ = 2)
       : CircuitSimulator(std::move(qc_), approxInfo_), mode(mode_),
         nthreads(nthreads_) {
-    qc::CircuitOptimizer::flattenOperations(*qc);
+    qc->flattenOperations();
     // remove final measurements
-    qc::CircuitOptimizer::removeFinalMeasurements(*qc);
+    qc->removeFinalMeasurements();
   }
 
   explicit HybridSchrodingerFeynmanSimulator(
@@ -56,8 +55,8 @@ class HybridSchrodingerFeynmanSimulator final : public CircuitSimulator {
       : CircuitSimulator(std::move(qc_), approxInfo_, seed_), mode(mode_),
         nthreads(nthreads_) {
     // remove final measurements
-    qc::CircuitOptimizer::flattenOperations(*qc);
-    qc::CircuitOptimizer::removeFinalMeasurements(*qc);
+    qc->flattenOperations();
+    qc->removeFinalMeasurements();
   }
 
   std::map<std::string, std::size_t> simulate(std::size_t shots) override;

include/PathSimulator.hpp

@@ -12,7 +12,6 @@
 
 #include "CircuitSimulator.hpp"
 #include "Simulator.hpp"
-#include "circuit_optimizer/CircuitOptimizer.hpp"
 #include "dd/Node.hpp"
 #include "ir/QuantumComputation.hpp"
 
@@ -167,7 +166,7 @@ class PathSimulator final : public CircuitSimulator {
 
     // remove final measurements implement measurement support for task-based
     // simulation
-    qc::CircuitOptimizer::removeFinalMeasurements(*(CircuitSimulator::qc));
+    CircuitSimulator::qc->removeFinalMeasurements();
 
     // case distinction for the starting point of the alternating strategy
     if (configuration.startingPoint == 0) {