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/* MIT License                                                                    */
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/* Copyright (c) 2020, 2021 JetBrains-Research                                    */
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#ifndef CUBOOL_CUDA_INSTANCE_HPP
#define CUBOOL_CUDA_INSTANCE_HPP

#include <core/config.hpp>
#include <unordered_set>

namespace cubool {

    /**
     * Manages global state for various internal operations.
     */
    class CudaInstance {
    public:

        enum MemType {
            Default,
            Managed
        };

        explicit CudaInstance(bool useManagedMemory);
        CudaInstance(const CudaInstance& other) = delete;
        CudaInstance(CudaInstance&& other) noexcept = delete;
        ~CudaInstance();

        // For custom host & device allocators
        void allocate(void* &ptr, size_t s) const;
        void allocateOnGpu(void* &ptr, size_t s) const;
        void deallocate(void* ptr) const;
        void deallocateOnGpu(void* ptr) const;
        void queryDeviceCapabilities(cuBool_DeviceCaps& deviceCaps) const;

        void syncHostDevice() const;
        MemType getMemoryType() const;

        static bool isCudaDeviceSupported();
        static CudaInstance& getInstanceRef();
        static CudaInstance* getInstancePtr();
        static bool isInstancePresent();

    private:
        MemType mMemoryType = Default;
        mutable size_t mHostAllocCount = 0;
        mutable size_t mDeviceAllocCount = 0;

        static volatile CudaInstance* gInstance;
    };

}

#endif //CUBOOL_CUDA_INSTANCE_HPP