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35 #ifndef GMX_GPU_UTILS_CUDA_KERNEL_UTILS_CUH
36 #define GMX_GPU_UTILS_CUDA_KERNEL_UTILS_CUH
39 * \brief CUDA device util functions (callable from GPU kernels).
41 * \author Szilard Pall <pall.szilard@gmail.com>
44 #include "gromacs/gpu_utils/cuda_arch_utils.cuh"
46 /*! Load directly or using __ldg() when supported. */
48 __device__ __forceinline__ T LDG(const T* ptr)
50 #if GMX_PTX_ARCH >= 350
51 /* CC >=3.5 supports constant loads through texture or L1 */
54 /* Device does not have LDG support, fall back to direct load. */
59 /*! \brief Fetch the value by \p index from the texture object.
61 * \tparam[in] T Raw data type
62 * \param[in] texObj Table texture object
63 * \param[in] index Non-negative element index
64 * \returns The value from the table at \p index
67 static __forceinline__ __device__ T fetchFromTexture(const cudaTextureObject_t texObj, int index)
70 // NOLINTNEXTLINE(misc-static-assert)
71 assert(!c_disableCudaTextures);
72 return tex1Dfetch<T>(texObj, index);
75 /*! \brief Fetch the value by \p index from the parameter lookup table.
77 * Depending on what is supported, it fetches parameters either
78 * using direct load or texture objects.
80 * \tparam[in] T Raw data type
81 * \param[in] d_ptr Device pointer to the raw table memory
82 * \param[in] texObj Table texture object
83 * \param[in] index Non-negative element index
84 * \returns The value from the table at \p index
87 static __forceinline__ __device__ T fetchFromParamLookupTable(const T* d_ptr,
88 const cudaTextureObject_t texObj,
93 #if DISABLE_CUDA_TEXTURES
94 GMX_UNUSED_VALUE(texObj);
95 result = LDG(d_ptr + index);
97 GMX_UNUSED_VALUE(d_ptr);
98 result = fetchFromTexture<T>(texObj, index);
104 #endif /* GMX_GPU_UTILS_CUDA_KERNEL_UTILS_CUH */