WarpReduceShfl provides SHFL-based variants of parallel reduction of items partitioned across a CUDA thread warp. More...

Detailed Description

template<typename T, int LOGICAL_WARP_THREADS, int PTX_ARCH>
struct cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >

WarpReduceShfl provides SHFL-based variants of parallel reduction of items partitioned across a CUDA thread warp.

LOGICAL_WARP_THREADS must be a power-of-two< The PTX compute capability for which to to specialize this collective

Definition at line 58 of file warp_reduce_shfl.cuh.

Data Structures
struct	IsInteger

Public Types
enum	{ IS_ARCH_WARP = (LOGICAL_WARP_THREADS == CUB_WARP_THREADS(PTX_ARCH)), STEPS = Log2<LOGICAL_WARP_THREADS>::VALUE, LOGICAL_WARPS = CUB_WARP_THREADS(PTX_ARCH) / LOGICAL_WARP_THREADS, SHFL_C = (CUB_WARP_THREADS(PTX_ARCH) - LOGICAL_WARP_THREADS) << 8 }

typedef NullType	TempStorage
	Shared memory storage layout type.

Public Member Functions
__device__ __forceinline__	WarpReduceShfl (TempStorage &)
	Constructor.

__device__ __forceinline__ unsigned int	ReduceStep (unsigned int input, cub::Sum, int last_lane, int offset)
	Reduction (specialized for summation across uint32 types) More...

__device__ __forceinline__ float	ReduceStep (float input, cub::Sum, int last_lane, int offset)
	Reduction (specialized for summation across fp32 types) More...

__device__ __forceinline__ unsigned long long	ReduceStep (unsigned long long input, cub::Sum, int last_lane, int offset)
	Reduction (specialized for summation across unsigned long long types) More...

__device__ __forceinline__ long long	ReduceStep (long long input, cub::Sum, int last_lane, int offset)
	Reduction (specialized for summation across long long types) More...

__device__ __forceinline__ double	ReduceStep (double input, cub::Sum, int last_lane, int offset)
	Reduction (specialized for summation across double types) More...

template<typename ValueT , typename KeyT >
__device__ __forceinline__ KeyValuePair< KeyT, ValueT >	ReduceStep (KeyValuePair< KeyT, ValueT > input, SwizzleScanOp< ReduceByKeyOp< cub::Sum > >, int last_lane, int offset)
	Reduction (specialized for swizzled ReduceByKeyOp<cub::Sum> across KeyValuePair<KeyT, ValueT> types) More...

template<typename ValueT , typename OffsetT >
__device__ __forceinline__ KeyValuePair< OffsetT, ValueT >	ReduceStep (KeyValuePair< OffsetT, ValueT > input, SwizzleScanOp< ReduceBySegmentOp< cub::Sum > >, int last_lane, int offset)
	Reduction (specialized for swizzled ReduceBySegmentOp<cub::Sum> across KeyValuePair<OffsetT, ValueT> types) More...

template<typename _T , typename ReductionOp >
__device__ __forceinline__ _T	ReduceStep (_T input, ReductionOp reduction_op, int last_lane, int offset)
	Reduction step (generic) More...

template<typename _T , typename ReductionOp >
__device__ __forceinline__ _T	ReduceStep (_T input, ReductionOp reduction_op, int last_lane, int offset, Int2Type< true >)
	Reduction step (specialized for small unsigned integers size 32b or less) More...

template<typename _T , typename ReductionOp >
__device__ __forceinline__ _T	ReduceStep (_T input, ReductionOp reduction_op, int last_lane, int offset, Int2Type< false >)
	Reduction step (specialized for types other than small unsigned integers size 32b or less) More...

template<typename ReductionOp , int STEP>
__device__ __forceinline__ void	ReduceStep (T &input, ReductionOp reduction_op, int last_lane, Int2Type< STEP >)

template<typename ReductionOp >
__device__ __forceinline__ void	ReduceStep (T &, ReductionOp, int, Int2Type< STEPS >)

template<bool ALL_LANES_VALID, typename ReductionOp >
__device__ __forceinline__ T	Reduce (T input, int valid_items, ReductionOp reduction_op)
	Reduction. More...

template<bool HEAD_SEGMENTED, typename FlagT , typename ReductionOp >
__device__ __forceinline__ T	SegmentedReduce (T input, FlagT flag, ReductionOp reduction_op)
	Segmented reduction. More...

Data Fields
unsigned int	lane_id
	Lane index in logical warp.

unsigned int	warp_id
	Logical warp index in 32-thread physical warp.

unsigned int	member_mask
	32-thread physical warp member mask of logical warp

Member Enumeration Documentation

◆ anonymous enum

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

anonymous enum

Enumerator
IS_ARCH_WARP	Whether the logical warp size and the PTX warp size coincide.
STEPS	The number of warp reduction steps.
LOGICAL_WARPS	Number of logical warps in a PTX warp.
SHFL_C	The 5-bit SHFL mask for logically splitting warps into sub-segments starts 8-bits up.

Definition at line 64 of file warp_reduce_shfl.cuh.

Member Function Documentation

◆ Reduce()

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<bool ALL_LANES_VALID, typename ReductionOp >

__device__ __forceinline__ T cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::Reduce	(	T	input,
		int	valid_items,
		ReductionOp	reduction_op
	)

inline

Reduction.

Parameters

[in]	input	Calling thread's input
[in]	valid_items	Total number of valid items across the logical warp
[in]	reduction_op	Binary reduction operator

Definition at line 466 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [1/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

__device__ __forceinline__ unsigned int cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	unsigned int	input,
		cub::Sum	,
		int	last_lane,
		int	offset
	)

inline

Reduction (specialized for summation across uint32 types)

Parameters

[in]	input	Calling thread's input item.
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 134 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [2/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

__device__ __forceinline__ float cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	float	input,
		cub::Sum	,
		int	last_lane,
		int	offset
	)

inline

Reduction (specialized for summation across fp32 types)

Parameters

[in]	input	Calling thread's input item.
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 171 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [3/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

__device__ __forceinline__ unsigned long long cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	unsigned long long	input,
		cub::Sum	,
		int	last_lane,
		int	offset
	)

inline

Reduction (specialized for summation across unsigned long long types)

Parameters

[in]	input	Calling thread's input item.
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 208 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [4/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

__device__ __forceinline__ long long cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	long long	input,
		cub::Sum	,
		int	last_lane,
		int	offset
	)

inline

Reduction (specialized for summation across long long types)

Parameters

[in]	input	Calling thread's input item.
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 250 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [5/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

__device__ __forceinline__ double cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	double	input,
		cub::Sum	,
		int	last_lane,
		int	offset
	)

inline

Reduction (specialized for summation across double types)

Parameters

[in]	input	Calling thread's input item.
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 293 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [6/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<typename ValueT , typename KeyT >

__device__ __forceinline__ KeyValuePair<KeyT, ValueT> cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	KeyValuePair< KeyT, ValueT >	input,
		SwizzleScanOp< ReduceByKeyOp< cub::Sum > >	,
		int	last_lane,
		int	offset
	)

inline

Reduction (specialized for swizzled ReduceByKeyOp<cub::Sum> across KeyValuePair<KeyT, ValueT> types)

Parameters

[in]	input	Calling thread's input item.
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 341 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [7/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<typename ValueT , typename OffsetT >

__device__ __forceinline__ KeyValuePair<OffsetT, ValueT> cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	KeyValuePair< OffsetT, ValueT >	input,
		SwizzleScanOp< ReduceBySegmentOp< cub::Sum > >	,
		int	last_lane,
		int	offset
	)

inline

Reduction (specialized for swizzled ReduceBySegmentOp<cub::Sum> across KeyValuePair<OffsetT, ValueT> types)

Parameters

[in]	input	Calling thread's input item.
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 369 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [8/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<typename _T , typename ReductionOp >

__device__ __forceinline__ _T cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	_T	input,
		ReductionOp	reduction_op,
		int	last_lane,
		int	offset
	)

inline

Reduction step (generic)

Parameters

[in]	input	Calling thread's input item.
[in]	reduction_op	Binary reduction operator
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 389 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [9/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<typename _T , typename ReductionOp >

__device__ __forceinline__ _T cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	_T	input,
		ReductionOp	reduction_op,
		int	last_lane,
		int	offset,
		Int2Type< true >
	)

inline

Reduction step (specialized for small unsigned integers size 32b or less)

Parameters

[in]	input	Calling thread's input item.
[in]	reduction_op	Binary reduction operator
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 409 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [10/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<typename _T , typename ReductionOp >

__device__ __forceinline__ _T cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	_T	input,
		ReductionOp	reduction_op,
		int	last_lane,
		int	offset,
		Int2Type< false >
	)

inline

Reduction step (specialized for types other than small unsigned integers size 32b or less)

Parameters

[in]	input	Calling thread's input item.
[in]	reduction_op	Binary reduction operator
[in]	last_lane	Index of last lane in segment
[in]	offset	Up-offset to pull from

Definition at line 422 of file warp_reduce_shfl.cuh.

◆ ReduceStep() [11/11]

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<typename ReductionOp , int STEP>

__device__ __forceinline__ void cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::ReduceStep	(	T &	input,
		ReductionOp	reduction_op,
		int	last_lane,
		Int2Type< STEP >
	)

inline

Parameters

[in]	input	Calling thread's input item.
[in]	reduction_op	Binary reduction operator
[in]	last_lane	Index of last lane in segment

Definition at line 438 of file warp_reduce_shfl.cuh.

◆ SegmentedReduce()

template<typename T , int LOGICAL_WARP_THREADS, int PTX_ARCH>

template<bool HEAD_SEGMENTED, typename FlagT , typename ReductionOp >

__device__ __forceinline__ T cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >::SegmentedReduce	(	T	input,
		FlagT	flag,
		ReductionOp	reduction_op
	)

inline

Segmented reduction.

Parameters

[in]	input	Calling thread's input
[in]	flag	Whether or not the current lane is a segment head/tail
[in]	reduction_op	Binary reduction operator

Definition at line 496 of file warp_reduce_shfl.cuh.

The documentation for this struct was generated from the following file:

openfpm_data/src/util/cuda/cub_old/warp/specializations/warp_reduce_shfl.cuh

Detailed Description

template<typename T, int LOGICAL_WARP_THREADS, int PTX_ARCH> struct cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >

Data Structures

Public Types

Public Member Functions

Data Fields

Member Enumeration Documentation

◆ anonymous enum

Member Function Documentation

◆ Reduce()

◆ ReduceStep() [1/11]

◆ ReduceStep() [2/11]

◆ ReduceStep() [3/11]

◆ ReduceStep() [4/11]

◆ ReduceStep() [5/11]

◆ ReduceStep() [6/11]

◆ ReduceStep() [7/11]

◆ ReduceStep() [8/11]

◆ ReduceStep() [9/11]

◆ ReduceStep() [10/11]

◆ ReduceStep() [11/11]

◆ SegmentedReduce()

template<typename T, int LOGICAL_WARP_THREADS, int PTX_ARCH>
struct cub::WarpReduceShfl< T, LOGICAL_WARP_THREADS, PTX_ARCH >