histogram_common.h

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#ifndef HISTOGRAM_COMMON_H
#define HISTOGRAM_COMMON_H

////////////////////////////////////////////////////////////////////////////////
// Common definitions
////////////////////////////////////////////////////////////////////////////////
#define HISTOGRAM64_BIN_COUNT 64
#define HISTOGRAM256_BIN_COUNT 256
#define UINT_BITS 32
typedef unsigned int uint;
typedef unsigned char uchar;

////////////////////////////////////////////////////////////////////////////////
// GPU-specific common definitions
////////////////////////////////////////////////////////////////////////////////
#define LOG2_WARP_SIZE 5U
#define WARP_SIZE (1U << LOG2_WARP_SIZE)

// May change on future hardware, so better parametrize the code
#define SHARED_MEMORY_BANKS 16

// Threadblock size: must be a multiple of (4 * SHARED_MEMORY_BANKS)
// because of the bit permutation of threadIdx.x
#define HISTOGRAM64_THREADBLOCK_SIZE (4 * SHARED_MEMORY_BANKS)

// Warps ==subhistograms per threadblock
#define WARP_COUNT 6

// Threadblock size
#define HISTOGRAM256_THREADBLOCK_SIZE (WARP_COUNT * WARP_SIZE)

// Shared memory per threadblock
#define HISTOGRAM256_THREADBLOCK_MEMORY (WARP_COUNT * HISTOGRAM256_BIN_COUNT)

#define UMUL(a, b) ((a) * (b))
#define UMAD(a, b, c) (UMUL((a), (b)) + (c))

////////////////////////////////////////////////////////////////////////////////
// Reference CPU histogram
////////////////////////////////////////////////////////////////////////////////
extern "C" void histogram64CPU(uint *h_Histogram, void *h_Data, uint byteCount);

extern "C" void histogram256CPU(uint *h_Histogram, void *h_Data,
                                uint byteCount);

////////////////////////////////////////////////////////////////////////////////
// GPU histogram
////////////////////////////////////////////////////////////////////////////////
extern "C" void initHistogram64(void);
extern "C" void initHistogram256(void);
extern "C" void closeHistogram64(void);
extern "C" void closeHistogram256(void);

extern "C" void histogram64(uint *d_Histogram, void *d_Data, uint byteCount);

extern "C" void histogram256(uint *d_Histogram, void *d_Data, uint byteCount);

#endif