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device_reduce_by_key.cuh

/******************************************************************************
* Copyright (c) 2011, Duane Merrill. All rights reserved.
* Copyright (c) 2011-2013, NVIDIA CORPORATION. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the NVIDIA CORPORATION nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NVIDIA CORPORATION BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
******************************************************************************/
/**
* \file
* cub::DeviceReduceByKey provides operations for computing a device-wide, parallel prefix scan across data items residing within global memory.
*/
#pragma once
#include <stdio.h>
#include <iterator>
#include "block/block_reduce_by_key_tiles.cuh"
#include "device_scan.cuh"
#include "../thread/thread_operators.cuh"
#include "../grid/grid_queue.cuh"
#include "../util_iterator.cuh"
#include "../util_debug.cuh"
#include "../util_device.cuh"
#include "../util_namespace.cuh"
/// Optional outer namespace(s)
CUB_NS_PREFIX
/// CUB namespace
namespace cub {
/******************************************************************************
* Kernel entry points
*****************************************************************************/
#ifndef DOXYGEN_SHOULD_SKIP_THIS // Do not document
/**
* Reduce-by-key kernel entry point (multi-block)
*/
template <
typename BlockReduceByKeyilesPolicy, ///< Tuning policy for cub::BlockReduceByKeyiles abstraction
typename InputIteratorRA, ///< Random-access iterator type for input (may be a simple pointer type)
typename OutputIteratorRA, ///< Random-access iterator type for output (may be a simple pointer type)
typename T, ///< The scan data type
typename ReductionOp, ///< Binary scan operator type having member <tt>T operator()(const T &a, const T &b)</tt>
typename Identity, ///< Identity value type (cub::NullType for inclusive scans)
typename SizeT> ///< Integer type used for global array indexing
__launch_bounds__ (int(BlockSweepScanPolicy::BLOCK_THREADS))
__global__ void MultiBlockScanKernel(
InputIteratorRA d_in, ///< Input data
OutputIteratorRA d_out, ///< Output data
ScanTileDescriptor<T> *d_tile_status, ///< Global list of tile status
ReductionOp reduction_op, ///< Binary scan operator
Identity identity, ///< Identity element
SizeT num_items, ///< Total number of scan items for the entire problem
GridQueue<int> queue) ///< Descriptor for performing dynamic mapping of tile data to thread blocks
{
enum
{
TILE_STATUS_PADDING = PtxArchProps::WARP_THREADS,
};
// Thread block type for scanning input tiles
typedef BlockSweepScan<
BlockSweepScanPolicy,
InputIteratorRA,
OutputIteratorRA,
ReductionOp,
Identity,
SizeT> BlockSweepScanT;
// Shared memory for BlockSweepScan
__shared__ typename BlockSweepScanT::TempStorage temp_storage;
// Process tiles
BlockSweepScanT(temp_storage, d_in, d_out, reduction_op, identity).ConsumeTiles(
num_items,
queue,
d_tile_status + TILE_STATUS_PADDING);
}
#endif // DOXYGEN_SHOULD_SKIP_THIS
/******************************************************************************
* DeviceReduceByKey
*****************************************************************************/
/**
* \addtogroup DeviceModule
* @{
*/
/**
* \brief DeviceReduceByKey provides operations for computing a device-wide, parallel prefix scan across data items residing within global memory. ![](scan_logo.png)
*/
struct DeviceReduceByKey
{
#ifndef DOXYGEN_SHOULD_SKIP_THIS // Do not document
/******************************************************************************
* Constants and typedefs
******************************************************************************/
/// Generic structure for encapsulating dispatch properties. Mirrors the constants within BlockSweepScanPolicy.
struct KernelDispachParams
{
// Policy fields
int block_threads;
int items_per_thread;
BlockLoadAlgorithm load_policy;
BlockStoreAlgorithm store_policy;
BlockScanAlgorithm scan_algorithm;
// Other misc
int tile_size;
template <typename BlockSweepScanPolicy>
__host__ __device__ __forceinline__
void Init()
{
block_threads = BlockSweepScanPolicy::BLOCK_THREADS;
items_per_thread = BlockSweepScanPolicy::ITEMS_PER_THREAD;
load_policy = BlockSweepScanPolicy::LOAD_ALGORITHM;
store_policy = BlockSweepScanPolicy::STORE_ALGORITHM;
scan_algorithm = BlockSweepScanPolicy::SCAN_ALGORITHM;
tile_size = block_threads * items_per_thread;
}
__host__ __device__ __forceinline__
void Print()
{
printf("%d, %d, %d, %d, %d",
block_threads,
items_per_thread,
load_policy,
store_policy,
scan_algorithm);
}
};
/******************************************************************************
* Tuning policies
******************************************************************************/
/// Specializations of tuned policy types for different PTX architectures
template <
typename T,
typename SizeT,
int ARCH>
struct TunedPolicies;
/// SM35 tune
template <typename T, typename SizeT>
struct TunedPolicies<T, SizeT, 350>
{
typedef BlockSweepScanPolicy<128, 16, BLOCK_LOAD_DIRECT, false, LOAD_LDG, BLOCK_STORE_WARP_TRANSPOSE, true, BLOCK_SCAN_RAKING_MEMOIZE> MultiBlockPolicy;
};
/// SM30 tune
template <typename T, typename SizeT>
struct TunedPolicies<T, SizeT, 300>
{
typedef BlockSweepScanPolicy<256, 9, BLOCK_LOAD_WARP_TRANSPOSE, false, LOAD_DEFAULT, BLOCK_STORE_WARP_TRANSPOSE, false, BLOCK_SCAN_RAKING_MEMOIZE> MultiBlockPolicy;
};
/// SM20 tune
template <typename T, typename SizeT>
struct TunedPolicies<T, SizeT, 200>
{
typedef BlockSweepScanPolicy<128, 15, BLOCK_LOAD_WARP_TRANSPOSE, false, LOAD_DEFAULT, BLOCK_STORE_WARP_TRANSPOSE, false, BLOCK_SCAN_RAKING_MEMOIZE> MultiBlockPolicy;
};
/// SM10 tune
template <typename T, typename SizeT>
struct TunedPolicies<T, SizeT, 100>
{
typedef BlockSweepScanPolicy<128, 7, BLOCK_LOAD_TRANSPOSE, false, LOAD_DEFAULT, BLOCK_STORE_TRANSPOSE, false, BLOCK_SCAN_RAKING> MultiBlockPolicy;
};
/// Tuning policy for the PTX architecture that DeviceReduceByKey operations will get dispatched to
template <typename T, typename SizeT>
struct PtxDefaultPolicies
{
static const int PTX_TUNE_ARCH = (CUB_PTX_ARCH >= 350) ?
350 :
(CUB_PTX_ARCH >= 300) ?
300 :
(CUB_PTX_ARCH >= 200) ?
200 :
100;
// Tuned policy set for the current PTX compiler pass
typedef TunedPolicies<T, SizeT, PTX_TUNE_ARCH> PtxTunedPolicies;
// MultiBlockPolicy that opaquely derives from the specialization corresponding to the current PTX compiler pass
struct MultiBlockPolicy : PtxTunedPolicies::MultiBlockPolicy {};
/**
* Initialize dispatch params with the policies corresponding to the PTX assembly we will use
*/
static void InitDispatchParams(int ptx_version, KernelDispachParams &multi_block_dispatch_params)
{
if (ptx_version >= 350)
{
typedef TunedPolicies<T, SizeT, 350> TunedPolicies;
multi_block_dispatch_params.Init<typename TunedPolicies::MultiBlockPolicy>();
}
else if (ptx_version >= 300)
{
typedef TunedPolicies<T, SizeT, 300> TunedPolicies;
multi_block_dispatch_params.Init<typename TunedPolicies::MultiBlockPolicy>();
}
else if (ptx_version >= 200)
{
typedef TunedPolicies<T, SizeT, 200> TunedPolicies;
multi_block_dispatch_params.Init<typename TunedPolicies::MultiBlockPolicy>();
}
else
{
typedef TunedPolicies<T, SizeT, 100> TunedPolicies;
multi_block_dispatch_params.Init<typename TunedPolicies::MultiBlockPolicy>();
}
}
};
/******************************************************************************
* Utility methods
******************************************************************************/
/**
* Internal dispatch routine
*/
template <
typename InitScanKernelPtr, ///< Function type of cub::InitScanKernel
typename MultiBlockScanKernelPtr, ///< Function type of cub::MultiBlockScanKernel
typename InputIteratorRA, ///< Random-access iterator type for input (may be a simple pointer type)
typename OutputIteratorRA, ///< Random-access iterator type for output (may be a simple pointer type)
typename ReductionOp, ///< Binary scan operator type having member <tt>T operator()(const T &a, const T &b)</tt>
typename Identity, ///< Identity value type (cub::NullType for inclusive scans)
typename SizeT> ///< Integer type used for global array indexing
__host__ __device__ __forceinline__
static cudaError_t Dispatch(
void *d_temp_storage, ///< [in] %Device allocation of temporary storage. When NULL, the required allocation size is returned in \p temp_storage_bytes and no work is done.
size_t &temp_storage_bytes, ///< [in,out] Size in bytes of \p d_temp_storage allocation.
InitScanKernelPtr init_kernel, ///< [in] Kernel function pointer to parameterization of cub::InitScanKernel
MultiBlockScanKernelPtr multi_block_kernel, ///< [in] Kernel function pointer to parameterization of cub::MultiBlockScanKernel
KernelDispachParams &multi_block_dispatch_params, ///< [in] Dispatch parameters that match the policy that \p multi_block_kernel was compiled for
InputIteratorRA d_in, ///< [in] Iterator pointing to scan input
OutputIteratorRA d_out, ///< [in] Iterator pointing to scan output
ReductionOp reduction_op, ///< [in] Binary scan operator
Identity identity, ///< [in] Identity element
SizeT num_items, ///< [in] Total number of items to scan
cudaStream_t stream = 0, ///< [in] <b>[optional]</b> CUDA stream to launch kernels within. Default is stream<sub>0</sub>.
bool stream_synchronous = false) ///< [in] <b>[optional]</b> Whether or not to synchronize the stream after every kernel launch to check for errors. Default is \p false.
{
#ifndef CUB_RUNTIME_ENABLED
// Kernel launch not supported from this device
return CubDebug(cudaErrorNotSupported );
#else
enum
{
TILE_STATUS_PADDING = 32,
};
// Data type
typedef typename std::iterator_traits<InputIteratorRA>::value_type T;
cudaError error = cudaSuccess;
do
{
// Number of input tiles
int num_tiles = (num_items + multi_block_dispatch_params.tile_size - 1) / multi_block_dispatch_params.tile_size;
// Temporary storage allocation requirements
void* allocations[2];
size_t allocation_sizes[2] =
{
(num_tiles + TILE_STATUS_PADDING) * sizeof(ScanTileDescriptor<T>), // bytes needed for tile status descriptors
GridQueue<int>::AllocationSize() // bytes needed for grid queue descriptor
};
// Alias temporaries (or set the necessary size of the storage allocation)
if (CubDebug(error = AliasTemporaries(d_temp_storage, temp_storage_bytes, allocations, allocation_sizes))) break;
// Return if the caller is simply requesting the size of the storage allocation
if (d_temp_storage == NULL)
return cudaSuccess;
// Global list of tile status
ScanTileDescriptor<T> *d_tile_status = (ScanTileDescriptor<T>*) allocations[0];
// Grid queue descriptor
GridQueue<int> queue(allocations[1]);
// Get GPU id
int device_ordinal;
if (CubDebug(error = cudaGetDevice(&device_ordinal))) break;
// Get SM count
int sm_count;
if (CubDebug(error = cudaDeviceGetAttribute (&sm_count, cudaDevAttrMultiProcessorCount, device_ordinal))) break;
// Log init_kernel configuration
int init_kernel_threads = 128;
int init_grid_size = (num_tiles + init_kernel_threads - 1) / init_kernel_threads;
if (stream_synchronous) CubLog("Invoking init_kernel<<<%d, %d, 0, %lld>>>()\n", init_grid_size, init_kernel_threads, (long long) stream);
// Invoke init_kernel to initialize tile descriptors and queue descriptors
init_kernel<<<init_grid_size, init_kernel_threads, 0, stream>>>(
queue,
d_tile_status,
num_tiles);
// Sync the stream if specified
#ifndef __CUDA_ARCH__
if (stream_synchronous && CubDebug(error = cudaStreamSynchronize(stream))) break;
#else
if (stream_synchronous && CubDebug(error = cudaDeviceSynchronize())) break;
#endif
// Get a rough estimate of multi_block_kernel SM occupancy based upon the maximum SM occupancy of the targeted PTX architecture
int multi_sm_occupancy = CUB_MIN(
ArchProps<CUB_PTX_ARCH>::MAX_SM_THREADBLOCKS,
ArchProps<CUB_PTX_ARCH>::MAX_SM_THREADS / multi_block_dispatch_params.block_threads);
#ifndef __CUDA_ARCH__
// We're on the host, so come up with a more accurate estimate of multi_block_kernel SM occupancy from actual device properties
Device device_props;
if (CubDebug(error = device_props.Init(device_ordinal))) break;
if (CubDebug(error = device_props.MaxSmOccupancy(
multi_sm_occupancy,
multi_block_kernel,
multi_block_dispatch_params.block_threads))) break;
#endif
// Get device occupancy for multi_block_kernel
int multi_block_occupancy = multi_sm_occupancy * sm_count;
// Get grid size for multi_block_kernel
int multi_block_grid_size = (num_tiles < multi_block_occupancy) ?
num_tiles : // Not enough to fill the device with threadblocks
multi_block_occupancy; // Fill the device with threadblocks
// Log multi_block_kernel configuration
if (stream_synchronous) CubLog("Invoking multi_block_kernel<<<%d, %d, 0, %lld>>>(), %d items per thread, %d SM occupancy\n",
multi_block_grid_size, multi_block_dispatch_params.block_threads, (long long) stream, multi_block_dispatch_params.items_per_thread, multi_sm_occupancy);
// Invoke multi_block_kernel
multi_block_kernel<<<multi_block_grid_size, multi_block_dispatch_params.block_threads, 0, stream>>>(
d_in,
d_out,
d_tile_status,
reduction_op,
identity,
num_items,
queue);
// Sync the stream if specified
#ifndef __CUDA_ARCH__
if (stream_synchronous && CubDebug(error = cudaStreamSynchronize(stream))) break;
#else
if (stream_synchronous && CubDebug(error = cudaDeviceSynchronize())) break;
#endif
}
while (0);
return error;
#endif // CUB_RUNTIME_ENABLED
}
/**
* Internal scan dispatch routine for using default tuning policies
*/
template <
typename InputIteratorRA, ///< Random-access iterator type for input (may be a simple pointer type)
typename OutputIteratorRA, ///< Random-access iterator type for output (may be a simple pointer type)
typename ReductionOp, ///< Binary scan operator type having member <tt>T operator()(const T &a, const T &b)</tt>
typename Identity, ///< Identity value type (cub::NullType for inclusive scans)
typename SizeT> ///< Integer type used for global array indexing
__host__ __device__ __forceinline__
static cudaError_t Dispatch(
void *d_temp_storage, ///< [in] %Device allocation of temporary storage. When NULL, the required allocation size is returned in \p temp_storage_bytes and no work is done.
size_t &temp_storage_bytes, ///< [in,out] Size in bytes of \p d_temp_storage allocation.
InputIteratorRA d_in, ///< [in] Iterator pointing to scan input
OutputIteratorRA d_out, ///< [in] Iterator pointing to scan output
ReductionOp reduction_op, ///< [in] Binary scan operator
Identity identity, ///< [in] Identity element
SizeT num_items, ///< [in] Total number of items to scan
cudaStream_t stream = 0, ///< [in] <b>[optional]</b> CUDA stream to launch kernels within. Default is stream<sub>0</sub>.
bool stream_synchronous = false) ///< [in] <b>[optional]</b> Whether or not to synchronize the stream after every kernel launch to check for errors. Default is \p false.
{
// Data type
typedef typename std::iterator_traits<InputIteratorRA>::value_type T;
// Tuning polices for the PTX architecture that will get dispatched to
typedef PtxDefaultPolicies<T, SizeT> PtxDefaultPolicies;
typedef typename PtxDefaultPolicies::MultiBlockPolicy MultiBlockPolicy;
cudaError error = cudaSuccess;
do
{
// Declare dispatch parameters
KernelDispachParams multi_block_dispatch_params;
#ifdef __CUDA_ARCH__
// We're on the device, so initialize the dispatch parameters with the PtxDefaultPolicies directly
multi_block_dispatch_params.Init<MultiBlockPolicy>();
#else
// We're on the host, so lookup and initialize the dispatch parameters with the policies that match the device's PTX version
int ptx_version;
if (CubDebug(error = PtxVersion(ptx_version))) break;
PtxDefaultPolicies::InitDispatchParams(ptx_version, multi_block_dispatch_params);
#endif
Dispatch(
d_temp_storage,
temp_storage_bytes,
InitScanKernel<T, SizeT>,
MultiBlockScanKernel<MultiBlockPolicy, InputIteratorRA, OutputIteratorRA, T, ReductionOp, Identity, SizeT>,
multi_block_dispatch_params,
d_in,
d_out,
reduction_op,
identity,
num_items,
stream,
stream_synchronous);
if (CubDebug(error)) break;
}
while (0);
return error;
}
#endif // DOXYGEN_SHOULD_SKIP_THIS
/******************************************************************//**
* Interface
*********************************************************************/
/**
* \brief Computes device-wide reductions of consecutive values whose corresponding keys are equal.
*
* The resulting output lists of value-aggregates and their corresponding keys are compacted.
*
* \devicestorage
*
* \tparam KeyInputIteratorRA <b>[inferred]</b> Random-access input iterator type for keys input (may be a simple pointer type)
* \tparam KeyOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for keys output (may be a simple pointer type)
* \tparam ValueInputIteratorRA <b>[inferred]</b> Random-access input iterator type for values input (may be a simple pointer type)
* \tparam ValueOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for values output (may be a simple pointer type)
* \tparam ReductionOp <b>[inferred]</b> Binary reduction operator type having member <tt>T operator()(const T &a, const T &b)</tt>, where \p T is the value type of \p ValueInputIteratorRA
*/
template <
typename KeyInputIteratorRA,
typename KeyOutputIteratorRA,
typename ValueInputIteratorRA,
typename ValueOutputIteratorRA,
typename ReductionOp>
__host__ __device__ __forceinline__
static cudaError_t ReduceValues(
void *d_temp_storage, ///< [in] %Device allocation of temporary storage. When NULL, the required allocation size is returned in \p temp_storage_bytes and no work is done.
size_t &temp_storage_bytes, ///< [in,out] Size in bytes of \p d_temp_storage allocation.
KeyInputIteratorRA d_keys_in, ///< [in] Key input data
KeyOutputIteratorRA d_keys_out, ///< [out] Key output data (compacted)
ValueInputIteratorRA d_values_in, ///< [in] Value input data
ValueOutputIteratorRA d_values_out, ///< [out] Value output data (compacted)
int num_items, ///< [in] Total number of input pairs
ReductionOp reduction_op, ///< [in] Binary value reduction operator
cudaStream_t stream = 0, ///< [in] <b>[optional]</b> CUDA stream to launch kernels within. Default is stream<sub>0</sub>.
bool stream_synchronous = false) ///< [in] <b>[optional]</b> Whether or not to synchronize the stream after every kernel launch to check for errors. May cause significant slowdown. Default is \p false.
{
return Dispatch(d_temp_storage, temp_storage_bytes, d_keys_in, d_keys_out, d_values_in, d_values_out, reduction_op, num_items, stream, stream_synchronous);
}
/**
* \brief Computes device-wide sums of consecutive values whose corresponding keys are equal.
*
* The resulting output lists of value-aggregates and their corresponding keys are compacted.
*
* \devicestorage
*
* \tparam KeyInputIteratorRA <b>[inferred]</b> Random-access input iterator type for keys input (may be a simple pointer type)
* \tparam KeyOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for keys output (may be a simple pointer type)
* \tparam ValueInputIteratorRA <b>[inferred]</b> Random-access input iterator type for values input (may be a simple pointer type)
* \tparam ValueOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for values output (may be a simple pointer type)
* \tparam ReductionOp <b>[inferred]</b> Binary reduction operator type having member <tt>T operator()(const T &a, const T &b)</tt>, where \p T is the value type of \p ValueInputIteratorRA
*/
template <
typename KeyInputIteratorRA,
typename KeyOutputIteratorRA,
typename ValueInputIteratorRA,
typename ValueOutputIteratorRA>
__host__ __device__ __forceinline__
static cudaError_t SumValues(
void *d_temp_storage, ///< [in] %Device allocation of temporary storage. When NULL, the required allocation size is returned in \p temp_storage_bytes and no work is done.
size_t &temp_storage_bytes, ///< [in,out] Size in bytes of \p d_temp_storage allocation.
KeyInputIteratorRA d_keys_in, ///< [in] Key input data
KeyOutputIteratorRA d_keys_out, ///< [in] Key output data (compacted)
ValueInputIteratorRA d_values_in, ///< [in] Value input data
ValueOutputIteratorRA d_values_out, ///< [in] Value output data (compacted)
int num_items, ///< [in] Total number of input pairs
cudaStream_t stream = 0, ///< [in] <b>[optional]</b> CUDA stream to launch kernels within. Default is stream<sub>0</sub>.
bool stream_synchronous = false) ///< [in] <b>[optional]</b> Whether or not to synchronize the stream after every kernel launch to check for errors. May cause significant slowdown. Default is \p false.
{
return ReduceValues(d_temp_storage, temp_storage_bytes, d_keys_in, d_keys_out, d_values_in, d_values_out, cub::Sum(), num_items, stream, stream_synchronous);
}
/**
* \brief Computes the "run-length" of each group of consecutive, equal-valued keys.
*
* The resulting output lists of run-length counts and their corresponding keys are compacted.
*
* \devicestorage
*
* \tparam KeyInputIteratorRA <b>[inferred]</b> Random-access input iterator type for keys input (may be a simple pointer type)
* \tparam KeyOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for keys output (may be a simple pointer type)
* \tparam CountOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for output of key-counts whose value type must be convertible to an integer type (may be a simple pointer type)
*/
template <
typename KeyInputIteratorRA,
typename KeyOutputIteratorRA,
typename CountOutputIteratorRA>
__host__ __device__ __forceinline__
static cudaError_t RunLengths(
void *d_temp_storage, ///< [in] %Device allocation of temporary storage. When NULL, the required allocation size is returned in \p temp_storage_bytes and no work is done.
size_t &temp_storage_bytes, ///< [in,out] Size in bytes of \p d_temp_storage allocation.
KeyInputIteratorRA d_keys_in, ///< [in] Key input data
KeyOutputIteratorRA d_keys_out, ///< [in] Key output data (compacted)
CountOutputIteratorRA d_counts_out, ///< [in] Run-length counts output data (compacted)
int num_items, ///< [in] Total number of keys
cudaStream_t stream = 0, ///< [in] <b>[optional]</b> CUDA stream to launch kernels within. Default is stream<sub>0</sub>.
bool stream_synchronous = false) ///< [in] <b>[optional]</b> Whether or not to synchronize the stream after every kernel launch to check for errors. May cause significant slowdown. Default is \p false.
{
typedef typename std::iterator_traits<CountOutputIteratorRA>::value_type CountT;
return SumValues(d_temp_storage, temp_storage_bytes, d_keys_in, d_keys_out, ConstantIteratorRA<CountT>(1), d_counts_out, num_items, stream, stream_synchronous);
}
/**
* \brief Removes duplicates within each group of consecutive, equal-valued keys. Only the first key from each group (and corresponding value) is kept.
*
* The resulting keys are compacted.
*
* \devicestorage
*
* \tparam KeyInputIteratorRA <b>[inferred]</b> Random-access input iterator type for keys input (may be a simple pointer type)
* \tparam KeyOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for keys output (may be a simple pointer type)
* \tparam ValueInputIteratorRA <b>[inferred]</b> Random-access input iterator type for values input (may be a simple pointer type)
* \tparam ValueOutputIteratorRA <b>[inferred]</b> Random-access output iterator type for values output (may be a simple pointer type)
* \tparam ReductionOp <b>[inferred]</b> Binary reduction operator type having member <tt>T operator()(const T &a, const T &b)</tt>, where \p T is the value type of \p ValueInputIteratorRA
*/
template <
typename KeyInputIteratorRA,
typename KeyOutputIteratorRA,
typename ValueInputIteratorRA,
typename ValueOutputIteratorRA,
typename ReductionOp>
__host__ __device__ __forceinline__
static cudaError_t Unique(
void *d_temp_storage, ///< [in] %Device allocation of temporary storage. When NULL, the required allocation size is returned in \p temp_storage_bytes and no work is done.
size_t &temp_storage_bytes, ///< [in,out] Size in bytes of \p d_temp_storage allocation.
KeyInputIteratorRA d_keys_in, ///< [in] Key input data
KeyOutputIteratorRA d_keys_out, ///< [out] Key output data (compacted)
ValueInputIteratorRA d_values_in, ///< [in] Value input data
ValueOutputIteratorRA d_values_out, ///< [out] Value output data (compacted)
int num_items, ///< [in] Total number of input pairs
cudaStream_t stream = 0, ///< [in] <b>[optional]</b> CUDA stream to launch kernels within. Default is stream<sub>0</sub>.
bool stream_synchronous = false) ///< [in] <b>[optional]</b> Whether or not to synchronize the stream after every kernel launch to check for errors. May cause significant slowdown. Default is \p false.
{
return Dispatch(d_temp_storage, temp_storage_bytes, d_keys_in, d_keys_out, d_values_in, d_values_out, reduction_op, num_items, stream, stream_synchronous);
}
};
/** @} */ // DeviceModule
} // CUB namespace
CUB_NS_POSTFIX // Optional outer namespace(s)

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