Merge pull request #1204 from lioncash/pimpl

core: Make the main System class use the PImpl idiom

5 files changed, 387 insertions, 279 deletions

diff --git a/src/core/core.cpp b/src/core/core.cpp
index 2293669e5..75c259068 100644
--- a/src/core/core.cpp
+++ b/src/core/core.cpp
@@ -27,135 +27,299 @@ namespace Core {
 
 /*static*/ System System::s_instance;
 
-System::System() = default;
+namespace {
+FileSys::VirtualFile GetGameFileFromPath(const FileSys::VirtualFilesystem& vfs,
+                                         const std::string& path) {
+    // To account for split 00+01+etc files.
+    std::string dir_name;
+    std::string filename;
+    Common::SplitPath(path, &dir_name, &filename, nullptr);
+    if (filename == "00") {
+        const auto dir = vfs->OpenDirectory(dir_name, FileSys::Mode::Read);
+        std::vector<FileSys::VirtualFile> concat;
+        for (u8 i = 0; i < 0x10; ++i) {
+            auto next = dir->GetFile(fmt::format("{:02X}", i));
+            if (next != nullptr)
+                concat.push_back(std::move(next));
+            else {
+                next = dir->GetFile(fmt::format("{:02x}", i));
+                if (next != nullptr)
+                    concat.push_back(std::move(next));
+                else
+                    break;
+            }
+        }
 
-System::~System() = default;
+        if (concat.empty())
+            return nullptr;
+
+        return FileSys::ConcatenateFiles(concat, dir->GetName());
+    }
+
+    return vfs->OpenFile(path, FileSys::Mode::Read);
+}
 
 /// Runs a CPU core while the system is powered on
-static void RunCpuCore(std::shared_ptr<Cpu> cpu_state) {
+void RunCpuCore(std::shared_ptr<Cpu> cpu_state) {
     while (Core::System::GetInstance().IsPoweredOn()) {
         cpu_state->RunLoop(true);
     }
 }
+} // Anonymous namespace
 
-Cpu& System::CurrentCpuCore() {
-    // If multicore is enabled, use host thread to figure out the current CPU core
-    if (Settings::values.use_multi_core) {
-        const auto& search = thread_to_cpu.find(std::this_thread::get_id());
-        ASSERT(search != thread_to_cpu.end());
-        ASSERT(search->second);
-        return *search->second;
+struct System::Impl {
+    Cpu& CurrentCpuCore() {
+        if (Settings::values.use_multi_core) {
+            const auto& search = thread_to_cpu.find(std::this_thread::get_id());
+            ASSERT(search != thread_to_cpu.end());
+            ASSERT(search->second);
+            return *search->second;
+        }
+
+        // Otherwise, use single-threaded mode active_core variable
+        return *cpu_cores[active_core];
     }
 
-    // Otherwise, use single-threaded mode active_core variable
-    return *cpu_cores[active_core];
-}
+    ResultStatus RunLoop(bool tight_loop) {
+        status = ResultStatus::Success;
 
-System::ResultStatus System::RunLoop(bool tight_loop) {
-    status = ResultStatus::Success;
+        // Update thread_to_cpu in case Core 0 is run from a different host thread
+        thread_to_cpu[std::this_thread::get_id()] = cpu_cores[0];
 
-    // Update thread_to_cpu in case Core 0 is run from a different host thread
-    thread_to_cpu[std::this_thread::get_id()] = cpu_cores[0];
+        if (GDBStub::IsServerEnabled()) {
+            GDBStub::HandlePacket();
 
-    if (GDBStub::IsServerEnabled()) {
-        GDBStub::HandlePacket();
+            // If the loop is halted and we want to step, use a tiny (1) number of instructions to
+            // execute. Otherwise, get out of the loop function.
+            if (GDBStub::GetCpuHaltFlag()) {
+                if (GDBStub::GetCpuStepFlag()) {
+                    tight_loop = false;
+                } else {
+                    return ResultStatus::Success;
+                }
+            }
+        }
 
-        // If the loop is halted and we want to step, use a tiny (1) number of instructions to
-        // execute. Otherwise, get out of the loop function.
-        if (GDBStub::GetCpuHaltFlag()) {
-            if (GDBStub::GetCpuStepFlag()) {
-                tight_loop = false;
-            } else {
-                return ResultStatus::Success;
+        for (active_core = 0; active_core < NUM_CPU_CORES; ++active_core) {
+            cpu_cores[active_core]->RunLoop(tight_loop);
+            if (Settings::values.use_multi_core) {
+                // Cores 1-3 are run on other threads in this mode
+                break;
             }
         }
+
+        if (GDBStub::IsServerEnabled()) {
+            GDBStub::SetCpuStepFlag(false);
+        }
+
+        return status;
     }
 
-    for (active_core = 0; active_core < NUM_CPU_CORES; ++active_core) {
-        cpu_cores[active_core]->RunLoop(tight_loop);
+    ResultStatus Init(Frontend::EmuWindow& emu_window) {
+        LOG_DEBUG(HW_Memory, "initialized OK");
+
+        CoreTiming::Init();
+        kernel.Initialize();
+
+        // Create a default fs if one doesn't already exist.
+        if (virtual_filesystem == nullptr)
+            virtual_filesystem = std::make_shared<FileSys::RealVfsFilesystem>();
+
+        current_process = Kernel::Process::Create(kernel, "main");
+
+        cpu_barrier = std::make_shared<CpuBarrier>();
+        cpu_exclusive_monitor = Cpu::MakeExclusiveMonitor(cpu_cores.size());
+        for (size_t index = 0; index < cpu_cores.size(); ++index) {
+            cpu_cores[index] = std::make_shared<Cpu>(cpu_exclusive_monitor, cpu_barrier, index);
+        }
+
+        telemetry_session = std::make_unique<Core::TelemetrySession>();
+        service_manager = std::make_shared<Service::SM::ServiceManager>();
+
+        Service::Init(service_manager, virtual_filesystem);
+        GDBStub::Init();
+
+        renderer = VideoCore::CreateRenderer(emu_window);
+        if (!renderer->Init()) {
+            return ResultStatus::ErrorVideoCore;
+        }
+
+        gpu_core = std::make_unique<Tegra::GPU>(renderer->Rasterizer());
+
+        // Create threads for CPU cores 1-3, and build thread_to_cpu map
+        // CPU core 0 is run on the main thread
+        thread_to_cpu[std::this_thread::get_id()] = cpu_cores[0];
         if (Settings::values.use_multi_core) {
-            // Cores 1-3 are run on other threads in this mode
-            break;
+            for (size_t index = 0; index < cpu_core_threads.size(); ++index) {
+                cpu_core_threads[index] =
+                    std::make_unique<std::thread>(RunCpuCore, cpu_cores[index + 1]);
+                thread_to_cpu[cpu_core_threads[index]->get_id()] = cpu_cores[index + 1];
+            }
         }
-    }
 
-    if (GDBStub::IsServerEnabled()) {
-        GDBStub::SetCpuStepFlag(false);
+        LOG_DEBUG(Core, "Initialized OK");
+
+        // Reset counters and set time origin to current frame
+        GetAndResetPerfStats();
+        perf_stats.BeginSystemFrame();
+
+        return ResultStatus::Success;
     }
 
-    return status;
-}
+    ResultStatus Load(Frontend::EmuWindow& emu_window, const std::string& filepath) {
+        app_loader = Loader::GetLoader(GetGameFileFromPath(virtual_filesystem, filepath));
 
-System::ResultStatus System::SingleStep() {
-    return RunLoop(false);
-}
+        if (!app_loader) {
+            LOG_CRITICAL(Core, "Failed to obtain loader for {}!", filepath);
+            return ResultStatus::ErrorGetLoader;
+        }
+        std::pair<boost::optional<u32>, Loader::ResultStatus> system_mode =
+            app_loader->LoadKernelSystemMode();
 
-static FileSys::VirtualFile GetGameFileFromPath(const FileSys::VirtualFilesystem& vfs,
-                                                const std::string& path) {
-    // To account for split 00+01+etc files.
-    std::string dir_name;
-    std::string filename;
-    Common::SplitPath(path, &dir_name, &filename, nullptr);
-    if (filename == "00") {
-        const auto dir = vfs->OpenDirectory(dir_name, FileSys::Mode::Read);
-        std::vector<FileSys::VirtualFile> concat;
-        for (u8 i = 0; i < 0x10; ++i) {
-            auto next = dir->GetFile(fmt::format("{:02X}", i));
-            if (next != nullptr)
-                concat.push_back(std::move(next));
-            else {
-                next = dir->GetFile(fmt::format("{:02x}", i));
-                if (next != nullptr)
-                    concat.push_back(std::move(next));
-                else
-                    break;
-            }
+        if (system_mode.second != Loader::ResultStatus::Success) {
+            LOG_CRITICAL(Core, "Failed to determine system mode (Error {})!",
+                         static_cast<int>(system_mode.second));
+
+            return ResultStatus::ErrorSystemMode;
         }
 
-        if (concat.empty())
-            return nullptr;
+        ResultStatus init_result{Init(emu_window)};
+        if (init_result != ResultStatus::Success) {
+            LOG_CRITICAL(Core, "Failed to initialize system (Error {})!",
+                         static_cast<int>(init_result));
+            Shutdown();
+            return init_result;
+        }
 
-        return FileSys::ConcatenateFiles(concat, dir->GetName());
+        const Loader::ResultStatus load_result{app_loader->Load(current_process)};
+        if (load_result != Loader::ResultStatus::Success) {
+            LOG_CRITICAL(Core, "Failed to load ROM (Error {})!", static_cast<int>(load_result));
+            Shutdown();
+
+            return static_cast<ResultStatus>(static_cast<u32>(ResultStatus::ErrorLoader) +
+                                             static_cast<u32>(load_result));
+        }
+        status = ResultStatus::Success;
+        return status;
     }
 
-    return vfs->OpenFile(path, FileSys::Mode::Read);
-}
+    void Shutdown() {
+        // Log last frame performance stats
+        auto perf_results = GetAndResetPerfStats();
+        Telemetry().AddField(Telemetry::FieldType::Performance, "Shutdown_EmulationSpeed",
+                             perf_results.emulation_speed * 100.0);
+        Telemetry().AddField(Telemetry::FieldType::Performance, "Shutdown_Framerate",
+                             perf_results.game_fps);
+        Telemetry().AddField(Telemetry::FieldType::Performance, "Shutdown_Frametime",
+                             perf_results.frametime * 1000.0);
+
+        // Shutdown emulation session
+        renderer.reset();
+        GDBStub::Shutdown();
+        Service::Shutdown();
+        service_manager.reset();
+        telemetry_session.reset();
+        gpu_core.reset();
+
+        // Close all CPU/threading state
+        cpu_barrier->NotifyEnd();
+        if (Settings::values.use_multi_core) {
+            for (auto& thread : cpu_core_threads) {
+                thread->join();
+                thread.reset();
+            }
+        }
+        thread_to_cpu.clear();
+        for (auto& cpu_core : cpu_cores) {
+            cpu_core.reset();
+        }
+        cpu_barrier.reset();
 
-System::ResultStatus System::Load(Frontend::EmuWindow& emu_window, const std::string& filepath) {
-    app_loader = Loader::GetLoader(GetGameFileFromPath(virtual_filesystem, filepath));
+        // Shutdown kernel and core timing
+        kernel.Shutdown();
+        CoreTiming::Shutdown();
+
+        // Close app loader
+        app_loader.reset();
 
-    if (!app_loader) {
-        LOG_CRITICAL(Core, "Failed to obtain loader for {}!", filepath);
-        return ResultStatus::ErrorGetLoader;
+        LOG_DEBUG(Core, "Shutdown OK");
     }
-    std::pair<boost::optional<u32>, Loader::ResultStatus> system_mode =
-        app_loader->LoadKernelSystemMode();
 
-    if (system_mode.second != Loader::ResultStatus::Success) {
-        LOG_CRITICAL(Core, "Failed to determine system mode (Error {})!",
-                     static_cast<int>(system_mode.second));
+    Loader::ResultStatus GetGameName(std::string& out) const {
+        if (app_loader == nullptr)
+            return Loader::ResultStatus::ErrorNotInitialized;
+        return app_loader->ReadTitle(out);
+    }
 
-        return ResultStatus::ErrorSystemMode;
+    void SetStatus(ResultStatus new_status, const char* details = nullptr) {
+        status = new_status;
+        if (details) {
+            status_details = details;
+        }
     }
 
-    ResultStatus init_result{Init(emu_window)};
-    if (init_result != ResultStatus::Success) {
-        LOG_CRITICAL(Core, "Failed to initialize system (Error {})!",
-                     static_cast<int>(init_result));
-        System::Shutdown();
-        return init_result;
+    PerfStats::Results GetAndResetPerfStats() {
+        return perf_stats.GetAndResetStats(CoreTiming::GetGlobalTimeUs());
     }
 
-    const Loader::ResultStatus load_result{app_loader->Load(current_process)};
-    if (load_result != Loader::ResultStatus::Success) {
-        LOG_CRITICAL(Core, "Failed to load ROM (Error {})!", static_cast<int>(load_result));
-        System::Shutdown();
+    Kernel::KernelCore kernel;
+    /// RealVfsFilesystem instance
+    FileSys::VirtualFilesystem virtual_filesystem;
+    /// AppLoader used to load the current executing application
+    std::unique_ptr<Loader::AppLoader> app_loader;
+    std::unique_ptr<VideoCore::RendererBase> renderer;
+    std::unique_ptr<Tegra::GPU> gpu_core;
+    std::shared_ptr<Tegra::DebugContext> debug_context;
+    Kernel::SharedPtr<Kernel::Process> current_process;
+    std::shared_ptr<ExclusiveMonitor> cpu_exclusive_monitor;
+    std::shared_ptr<CpuBarrier> cpu_barrier;
+    std::array<std::shared_ptr<Cpu>, NUM_CPU_CORES> cpu_cores;
+    std::array<std::unique_ptr<std::thread>, NUM_CPU_CORES - 1> cpu_core_threads;
+    size_t active_core{}; ///< Active core, only used in single thread mode
+
+    /// Service manager
+    std::shared_ptr<Service::SM::ServiceManager> service_manager;
+
+    /// Telemetry session for this emulation session
+    std::unique_ptr<Core::TelemetrySession> telemetry_session;
+
+    ResultStatus status = ResultStatus::Success;
+    std::string status_details = "";
+
+    /// Map of guest threads to CPU cores
+    std::map<std::thread::id, std::shared_ptr<Cpu>> thread_to_cpu;
+
+    Core::PerfStats perf_stats;
+    Core::FrameLimiter frame_limiter;
+};
+
+System::System() : impl{std::make_unique<Impl>()} {}
+System::~System() = default;
+
+Cpu& System::CurrentCpuCore() {
+    return impl->CurrentCpuCore();
+}
+
+System::ResultStatus System::RunLoop(bool tight_loop) {
+    return impl->RunLoop(tight_loop);
+}
+
+System::ResultStatus System::SingleStep() {
+    return RunLoop(false);
+}
 
-        return static_cast<ResultStatus>(static_cast<u32>(ResultStatus::ErrorLoader) +
-                                         static_cast<u32>(load_result));
+void System::InvalidateCpuInstructionCaches() {
+    for (auto& cpu : impl->cpu_cores) {
+        cpu->ArmInterface().ClearInstructionCache();
     }
-    status = ResultStatus::Success;
-    return status;
+}
+
+System::ResultStatus System::Load(Frontend::EmuWindow& emu_window, const std::string& filepath) {
+    return impl->Load(emu_window, filepath);
+}
+
+bool System::IsPoweredOn() const {
+    return impl->cpu_barrier && impl->cpu_barrier->IsAlive();
 }
 
 void System::PrepareReschedule() {
@@ -163,131 +327,134 @@ void System::PrepareReschedule() {
 }
 
 PerfStats::Results System::GetAndResetPerfStats() {
-    return perf_stats.GetAndResetStats(CoreTiming::GetGlobalTimeUs());
+    return impl->GetAndResetPerfStats();
 }
 
-const std::shared_ptr<Kernel::Scheduler>& System::Scheduler(size_t core_index) {
-    ASSERT(core_index < NUM_CPU_CORES);
-    return cpu_cores[core_index]->Scheduler();
+Core::TelemetrySession& System::TelemetrySession() const {
+    return *impl->telemetry_session;
 }
 
-Kernel::KernelCore& System::Kernel() {
-    return kernel;
+ARM_Interface& System::CurrentArmInterface() {
+    return CurrentCpuCore().ArmInterface();
 }
 
-const Kernel::KernelCore& System::Kernel() const {
-    return kernel;
+size_t System::CurrentCoreIndex() {
+    return CurrentCpuCore().CoreIndex();
+}
+
+Kernel::Scheduler& System::CurrentScheduler() {
+    return *CurrentCpuCore().Scheduler();
+}
+
+const std::shared_ptr<Kernel::Scheduler>& System::Scheduler(size_t core_index) {
+    ASSERT(core_index < NUM_CPU_CORES);
+    return impl->cpu_cores[core_index]->Scheduler();
+}
+
+Kernel::SharedPtr<Kernel::Process>& System::CurrentProcess() {
+    return impl->current_process;
 }
 
 ARM_Interface& System::ArmInterface(size_t core_index) {
     ASSERT(core_index < NUM_CPU_CORES);
-    return cpu_cores[core_index]->ArmInterface();
+    return impl->cpu_cores[core_index]->ArmInterface();
 }
 
 Cpu& System::CpuCore(size_t core_index) {
     ASSERT(core_index < NUM_CPU_CORES);
-    return *cpu_cores[core_index];
+    return *impl->cpu_cores[core_index];
 }
 
-System::ResultStatus System::Init(Frontend::EmuWindow& emu_window) {
-    LOG_DEBUG(HW_Memory, "initialized OK");
+ExclusiveMonitor& System::Monitor() {
+    return *impl->cpu_exclusive_monitor;
+}
 
-    CoreTiming::Init();
-    kernel.Initialize();
+Tegra::GPU& System::GPU() {
+    return *impl->gpu_core;
+}
 
-    // Create a default fs if one doesn't already exist.
-    if (virtual_filesystem == nullptr)
-        virtual_filesystem = std::make_shared<FileSys::RealVfsFilesystem>();
+const Tegra::GPU& System::GPU() const {
+    return *impl->gpu_core;
+}
 
-    current_process = Kernel::Process::Create(kernel, "main");
+VideoCore::RendererBase& System::Renderer() {
+    return *impl->renderer;
+}
 
-    cpu_barrier = std::make_shared<CpuBarrier>();
-    cpu_exclusive_monitor = Cpu::MakeExclusiveMonitor(cpu_cores.size());
-    for (size_t index = 0; index < cpu_cores.size(); ++index) {
-        cpu_cores[index] = std::make_shared<Cpu>(cpu_exclusive_monitor, cpu_barrier, index);
-    }
+const VideoCore::RendererBase& System::Renderer() const {
+    return *impl->renderer;
+}
 
-    telemetry_session = std::make_unique<Core::TelemetrySession>();
-    service_manager = std::make_shared<Service::SM::ServiceManager>();
+Kernel::KernelCore& System::Kernel() {
+    return impl->kernel;
+}
 
-    Service::Init(service_manager, virtual_filesystem);
-    GDBStub::Init();
+const Kernel::KernelCore& System::Kernel() const {
+    return impl->kernel;
+}
 
-    renderer = VideoCore::CreateRenderer(emu_window);
-    if (!renderer->Init()) {
-        return ResultStatus::ErrorVideoCore;
-    }
+Core::PerfStats& System::GetPerfStats() {
+    return impl->perf_stats;
+}
 
-    gpu_core = std::make_unique<Tegra::GPU>(renderer->Rasterizer());
+const Core::PerfStats& System::GetPerfStats() const {
+    return impl->perf_stats;
+}
 
-    // Create threads for CPU cores 1-3, and build thread_to_cpu map
-    // CPU core 0 is run on the main thread
-    thread_to_cpu[std::this_thread::get_id()] = cpu_cores[0];
-    if (Settings::values.use_multi_core) {
-        for (size_t index = 0; index < cpu_core_threads.size(); ++index) {
-            cpu_core_threads[index] =
-                std::make_unique<std::thread>(RunCpuCore, cpu_cores[index + 1]);
-            thread_to_cpu[cpu_core_threads[index]->get_id()] = cpu_cores[index + 1];
-        }
-    }
+Core::FrameLimiter& System::FrameLimiter() {
+    return impl->frame_limiter;
+}
 
-    LOG_DEBUG(Core, "Initialized OK");
+const Core::FrameLimiter& System::FrameLimiter() const {
+    return impl->frame_limiter;
+}
 
-    // Reset counters and set time origin to current frame
-    GetAndResetPerfStats();
-    perf_stats.BeginSystemFrame();
+Loader::ResultStatus System::GetGameName(std::string& out) const {
+    return impl->GetGameName(out);
+}
 
-    return ResultStatus::Success;
+void System::SetStatus(ResultStatus new_status, const char* details) {
+    impl->SetStatus(new_status, details);
 }
 
-void System::Shutdown() {
-    // Log last frame performance stats
-    auto perf_results = GetAndResetPerfStats();
-    Telemetry().AddField(Telemetry::FieldType::Performance, "Shutdown_EmulationSpeed",
-                         perf_results.emulation_speed * 100.0);
-    Telemetry().AddField(Telemetry::FieldType::Performance, "Shutdown_Framerate",
-                         perf_results.game_fps);
-    Telemetry().AddField(Telemetry::FieldType::Performance, "Shutdown_Frametime",
-                         perf_results.frametime * 1000.0);
-
-    // Shutdown emulation session
-    renderer.reset();
-    GDBStub::Shutdown();
-    Service::Shutdown();
-    service_manager.reset();
-    telemetry_session.reset();
-    gpu_core.reset();
-
-    // Close all CPU/threading state
-    cpu_barrier->NotifyEnd();
-    if (Settings::values.use_multi_core) {
-        for (auto& thread : cpu_core_threads) {
-            thread->join();
-            thread.reset();
-        }
-    }
-    thread_to_cpu.clear();
-    for (auto& cpu_core : cpu_cores) {
-        cpu_core.reset();
-    }
-    cpu_barrier.reset();
+const std::string& System::GetStatusDetails() const {
+    return impl->status_details;
+}
 
-    // Shutdown kernel and core timing
-    kernel.Shutdown();
-    CoreTiming::Shutdown();
+Loader::AppLoader& System::GetAppLoader() const {
+    return *impl->app_loader;
+}
 
-    // Close app loader
-    app_loader.reset();
+void System::SetGPUDebugContext(std::shared_ptr<Tegra::DebugContext> context) {
+    impl->debug_context = std::move(context);
+}
 
-    LOG_DEBUG(Core, "Shutdown OK");
+std::shared_ptr<Tegra::DebugContext> System::GetGPUDebugContext() const {
+    return impl->debug_context;
+}
+
+void System::SetFilesystem(FileSys::VirtualFilesystem vfs) {
+    impl->virtual_filesystem = std::move(vfs);
+}
+
+FileSys::VirtualFilesystem System::GetFilesystem() const {
+    return impl->virtual_filesystem;
+}
+
+System::ResultStatus System::Init(Frontend::EmuWindow& emu_window) {
+    return impl->Init(emu_window);
+}
+
+void System::Shutdown() {
+    impl->Shutdown();
 }
 
 Service::SM::ServiceManager& System::ServiceManager() {
-    return *service_manager;
+    return *impl->service_manager;
 }
 
 const Service::SM::ServiceManager& System::ServiceManager() const {
-    return *service_manager;
+    return *impl->service_manager;
 }
 
 } // namespace Core
diff --git a/src/core/core.h b/src/core/core.h
index 2c18f7193..984e8f94c 100644
--- a/src/core/core.h
+++ b/src/core/core.h
@@ -94,11 +94,7 @@ public:
      * This function should only be used by GDB Stub to support breakpoints, memory updates and
      * step/continue commands.
      */
-    void InvalidateCpuInstructionCaches() {
-        for (auto& cpu : cpu_cores) {
-            cpu->ArmInterface().ClearInstructionCache();
-        }
-    }
+    void InvalidateCpuInstructionCaches();
 
     /// Shutdown the emulated system.
     void Shutdown();
@@ -117,17 +113,13 @@ public:
      * application).
      * @returns True if the emulated system is powered on, otherwise false.
      */
-    bool IsPoweredOn() const {
-        return cpu_barrier && cpu_barrier->IsAlive();
-    }
+    bool IsPoweredOn() const;
 
     /**
      * Returns a reference to the telemetry session for this emulation session.
      * @returns Reference to the telemetry session.
      */
-    Core::TelemetrySession& TelemetrySession() const {
-        return *telemetry_session;
-    }
+    Core::TelemetrySession& TelemetrySession() const;
 
     /// Prepare the core emulation for a reschedule
     void PrepareReschedule();
@@ -136,14 +128,13 @@ public:
     PerfStats::Results GetAndResetPerfStats();
 
     /// Gets an ARM interface to the CPU core that is currently running
-    ARM_Interface& CurrentArmInterface() {
-        return CurrentCpuCore().ArmInterface();
-    }
+    ARM_Interface& CurrentArmInterface();
 
     /// Gets the index of the currently running CPU core
-    size_t CurrentCoreIndex() {
-        return CurrentCpuCore().CoreIndex();
-    }
+    size_t CurrentCoreIndex();
+
+    /// Gets the scheduler for the CPU core that is currently running
+    Kernel::Scheduler& CurrentScheduler();
 
     /// Gets an ARM interface to the CPU core with the specified index
     ARM_Interface& ArmInterface(size_t core_index);
@@ -151,43 +142,26 @@ public:
     /// Gets a CPU interface to the CPU core with the specified index
     Cpu& CpuCore(size_t core_index);
 
+    /// Gets the exclusive monitor
+    ExclusiveMonitor& Monitor();
+
     /// Gets a mutable reference to the GPU interface
-    Tegra::GPU& GPU() {
-        return *gpu_core;
-    }
+    Tegra::GPU& GPU();
 
     /// Gets an immutable reference to the GPU interface.
-    const Tegra::GPU& GPU() const {
-        return *gpu_core;
-    }
+    const Tegra::GPU& GPU() const;
 
     /// Gets a mutable reference to the renderer.
-    VideoCore::RendererBase& Renderer() {
-        return *renderer;
-    }
+    VideoCore::RendererBase& Renderer();
 
     /// Gets an immutable reference to the renderer.
-    const VideoCore::RendererBase& Renderer() const {
-        return *renderer;
-    }
-
-    /// Gets the scheduler for the CPU core that is currently running
-    Kernel::Scheduler& CurrentScheduler() {
-        return *CurrentCpuCore().Scheduler();
-    }
-
-    /// Gets the exclusive monitor
-    ExclusiveMonitor& Monitor() {
-        return *cpu_exclusive_monitor;
-    }
+    const VideoCore::RendererBase& Renderer() const;
 
     /// Gets the scheduler for the CPU core with the specified index
     const std::shared_ptr<Kernel::Scheduler>& Scheduler(size_t core_index);
 
     /// Gets the current process
-    Kernel::SharedPtr<Kernel::Process>& CurrentProcess() {
-        return current_process;
-    }
+    Kernel::SharedPtr<Kernel::Process>& CurrentProcess();
 
     /// Provides a reference to the kernel instance.
     Kernel::KernelCore& Kernel();
@@ -195,49 +169,37 @@ public:
     /// Provides a constant reference to the kernel instance.
     const Kernel::KernelCore& Kernel() const;
 
-    /// Gets the name of the current game
-    Loader::ResultStatus GetGameName(std::string& out) const {
-        if (app_loader == nullptr)
-            return Loader::ResultStatus::ErrorNotInitialized;
-        return app_loader->ReadTitle(out);
-    }
+    /// Provides a reference to the internal PerfStats instance.
+    Core::PerfStats& GetPerfStats();
 
-    PerfStats perf_stats;
-    FrameLimiter frame_limiter;
+    /// Provides a constant reference to the internal PerfStats instance.
+    const Core::PerfStats& GetPerfStats() const;
 
-    void SetStatus(ResultStatus new_status, const char* details = nullptr) {
-        status = new_status;
-        if (details) {
-            status_details = details;
-        }
-    }
+    /// Provides a reference to the frame limiter;
+    Core::FrameLimiter& FrameLimiter();
 
-    const std::string& GetStatusDetails() const {
-        return status_details;
-    }
+    /// Provides a constant referent to the frame limiter
+    const Core::FrameLimiter& FrameLimiter() const;
 
-    Loader::AppLoader& GetAppLoader() const {
-        return *app_loader;
-    }
+    /// Gets the name of the current game
+    Loader::ResultStatus GetGameName(std::string& out) const;
+
+    void SetStatus(ResultStatus new_status, const char* details);
+
+    const std::string& GetStatusDetails() const;
+
+    Loader::AppLoader& GetAppLoader() const;
 
     Service::SM::ServiceManager& ServiceManager();
     const Service::SM::ServiceManager& ServiceManager() const;
 
-    void SetGPUDebugContext(std::shared_ptr<Tegra::DebugContext> context) {
-        debug_context = std::move(context);
-    }
+    void SetGPUDebugContext(std::shared_ptr<Tegra::DebugContext> context);
 
-    std::shared_ptr<Tegra::DebugContext> GetGPUDebugContext() const {
-        return debug_context;
-    }
+    std::shared_ptr<Tegra::DebugContext> GetGPUDebugContext() const;
 
-    void SetFilesystem(FileSys::VirtualFilesystem vfs) {
-        virtual_filesystem = std::move(vfs);
-    }
+    void SetFilesystem(FileSys::VirtualFilesystem vfs);
 
-    FileSys::VirtualFilesystem GetFilesystem() const {
-        return virtual_filesystem;
-    }
+    FileSys::VirtualFilesystem GetFilesystem() const;
 
 private:
     System();
@@ -253,34 +215,10 @@ private:
      */
     ResultStatus Init(Frontend::EmuWindow& emu_window);
 
-    Kernel::KernelCore kernel;
-    /// RealVfsFilesystem instance
-    FileSys::VirtualFilesystem virtual_filesystem;
-    /// AppLoader used to load the current executing application
-    std::unique_ptr<Loader::AppLoader> app_loader;
-    std::unique_ptr<VideoCore::RendererBase> renderer;
-    std::unique_ptr<Tegra::GPU> gpu_core;
-    std::shared_ptr<Tegra::DebugContext> debug_context;
-    Kernel::SharedPtr<Kernel::Process> current_process;
-    std::shared_ptr<ExclusiveMonitor> cpu_exclusive_monitor;
-    std::shared_ptr<CpuBarrier> cpu_barrier;
-    std::array<std::shared_ptr<Cpu>, NUM_CPU_CORES> cpu_cores;
-    std::array<std::unique_ptr<std::thread>, NUM_CPU_CORES - 1> cpu_core_threads;
-    size_t active_core{}; ///< Active core, only used in single thread mode
-
-    /// Service manager
-    std::shared_ptr<Service::SM::ServiceManager> service_manager;
-
-    /// Telemetry session for this emulation session
-    std::unique_ptr<Core::TelemetrySession> telemetry_session;
+    struct Impl;
+    std::unique_ptr<Impl> impl;
 
     static System s_instance;
-
-    ResultStatus status = ResultStatus::Success;
-    std::string status_details = "";
-
-    /// Map of guest threads to CPU cores
-    std::map<std::thread::id, std::shared_ptr<Cpu>> thread_to_cpu;
 };
 
 inline ARM_Interface& CurrentArmInterface() {
diff --git a/src/core/hle/service/nvdrv/devices/nvdisp_disp0.cpp b/src/core/hle/service/nvdrv/devices/nvdisp_disp0.cpp
index 8bc49935a..0b37098e1 100644
--- a/src/core/hle/service/nvdrv/devices/nvdisp_disp0.cpp
+++ b/src/core/hle/service/nvdrv/devices/nvdisp_disp0.cpp
@@ -7,6 +7,7 @@
 #include "core/core.h"
 #include "core/hle/service/nvdrv/devices/nvdisp_disp0.h"
 #include "core/hle/service/nvdrv/devices/nvmap.h"
+#include "core/perf_stats.h"
 #include "video_core/gpu.h"
 #include "video_core/renderer_base.h"
 
@@ -31,7 +32,7 @@ void nvdisp_disp0::flip(u32 buffer_handle, u32 offset, u32 format, u32 width, u3
         transform, crop_rect};
 
     auto& instance = Core::System::GetInstance();
-    instance.perf_stats.EndGameFrame();
+    instance.GetPerfStats().EndGameFrame();
     instance.Renderer().SwapBuffers(framebuffer);
 }
 
diff --git a/src/core/hle/service/nvflinger/nvflinger.cpp b/src/core/hle/service/nvflinger/nvflinger.cpp
index 3996c24fe..06040da6f 100644
--- a/src/core/hle/service/nvflinger/nvflinger.cpp
+++ b/src/core/hle/service/nvflinger/nvflinger.cpp
@@ -17,6 +17,7 @@
 #include "core/hle/service/nvdrv/nvdrv.h"
 #include "core/hle/service/nvflinger/buffer_queue.h"
 #include "core/hle/service/nvflinger/nvflinger.h"
+#include "core/perf_stats.h"
 #include "video_core/renderer_base.h"
 #include "video_core/video_core.h"
 
@@ -137,7 +138,7 @@ void NVFlinger::Compose() {
             auto& system_instance = Core::System::GetInstance();
 
             // There was no queued buffer to draw, render previous frame
-            system_instance.perf_stats.EndGameFrame();
+            system_instance.GetPerfStats().EndGameFrame();
             system_instance.Renderer().SwapBuffers({});
             continue;
         }
diff --git a/src/video_core/renderer_opengl/renderer_opengl.cpp b/src/video_core/renderer_opengl/renderer_opengl.cpp
index 73d6419b4..3c4a9f17c 100644
--- a/src/video_core/renderer_opengl/renderer_opengl.cpp
+++ b/src/video_core/renderer_opengl/renderer_opengl.cpp
@@ -14,6 +14,7 @@
 #include "core/core_timing.h"
 #include "core/frontend/emu_window.h"
 #include "core/memory.h"
+#include "core/perf_stats.h"
 #include "core/settings.h"
 #include "core/tracer/recorder.h"
 #include "video_core/renderer_opengl/gl_rasterizer.h"
@@ -115,7 +116,7 @@ RendererOpenGL::~RendererOpenGL() = default;
 void RendererOpenGL::SwapBuffers(boost::optional<const Tegra::FramebufferConfig&> framebuffer) {
     ScopeAcquireGLContext acquire_context{render_window};
 
-    Core::System::GetInstance().perf_stats.EndSystemFrame();
+    Core::System::GetInstance().GetPerfStats().EndSystemFrame();
 
     // Maintain the rasterizer's state as a priority
     OpenGLState prev_state = OpenGLState::GetCurState();
@@ -140,8 +141,8 @@ void RendererOpenGL::SwapBuffers(boost::optional<const Tegra::FramebufferConfig&
 
     render_window.PollEvents();
 
-    Core::System::GetInstance().frame_limiter.DoFrameLimiting(CoreTiming::GetGlobalTimeUs());
-    Core::System::GetInstance().perf_stats.BeginSystemFrame();
+    Core::System::GetInstance().FrameLimiter().DoFrameLimiting(CoreTiming::GetGlobalTimeUs());
+    Core::System::GetInstance().GetPerfStats().BeginSystemFrame();
 
     // Restore the rasterizer state
     prev_state.Apply();