DSPLIB_lud

Introduction

Kernel for LU decomposition of input matrix.

• This function decomposes the square matrix \(A\) into a lower triangular matrix, upper triangular matrix, and a permutation matrix where:

  \begin{eqnarray*} A = P^{T} \times L \times U \qquad where &(1)&\;P\;is\;a\;permutation\;matrix\\ &(2)&\;L\;is\;a\;lower\;triangular\;matrix\\ &(3)&\;U\;is\;a\;upper\;triangular\;matrix\\ \end{eqnarray*}

• The Gaussian elimination outer product algorithm is used.
• The permutation matrix \(P\) keeps track of the reordering of rows in the \(A\) matrix such that the first element of the permuted matrix is maximum and nonzero.
• Input \(A\) is of the shape (M, M).
• Output matrices \(P\), \(L\) and \(U\) are of the shape (M, M)

Data Structures
struct	DSPLIB_ludInitArgs
	Structure containing the parameters to initialize the kernel. More...

Functions
int32_t	DSPLIB_lud_getHandleSize (DSPLIB_ludInitArgs *pKerInitArgs)
	This is a query function to calculate the size of internal handle. More...
DSPLIB_STATUS	DSPLIB_lud_init_checkParams (DSPLIB_kernelHandle handle, const DSPLIB_bufParams2D_t *bufParamsA, const DSPLIB_bufParams2D_t *bufParamsL, const DSPLIB_bufParams2D_t *bufParamsU, const DSPLIB_bufParams2D_t *bufParamsP, const DSPLIB_ludInitArgs *pKerInitArgs)
	This function checks the validity of the parameters passed to DSPLIB_lud_init function. This function is called with the same parameters as the DSPLIB_lud_init, and this function must be called before the DSPLIB_lud_init is called. More...
DSPLIB_STATUS	DSPLIB_lud_init (DSPLIB_kernelHandle handle, const DSPLIB_bufParams2D_t *bufParamsA, const DSPLIB_bufParams2D_t *bufParamsL, const DSPLIB_bufParams2D_t *bufParamsU, const DSPLIB_bufParams2D_t *bufParamsP, const DSPLIB_ludInitArgs *pKerInitArgs)
	This function should be called before the DSPLIB_lud_exec function is called. This function takes care of any one-time operations such as setting up the configuration of required hardware resources such as the streaming engine and streaming address generator. The results of these operations are stored in the handle. More...
DSPLIB_STATUS	DSPLIB_lud_exec_checkParams (DSPLIB_kernelHandle handle, const void *restrict pA, const void *restrict pL, const void *restrict pU, const void *restrict pP)
	This function checks the validity of the parameters passed to DSPLIB_lud_exec function. This function is called with the same parameters as the DSPLIB_lud_exec, and this function must be called before the DSPLIB_lud_exec is called. More...
DSPLIB_STATUS	DSPLIB_lud_exec (DSPLIB_kernelHandle handle, void *restrict pA, void *restrict pL, void *restrict pU, void *restrict pP)
	This function is the main kernel compute function. More...

Function Documentation

DSPLIB_lud_getHandleSize()

int32_t DSPLIB_lud_getHandleSize

(

DSPLIB_ludInitArgs *

pKerInitArgs

)

This is a query function to calculate the size of internal handle.

Parameters

[in]

pKerInitArgs

: Pointer to structure holding init parameters

Returns

Size of the buffer in bytes

Remarks

Application is expected to allocate buffer of the requested size and provide it as input to other functions requiring it.

Definition at line 25 of file DSPLIB_lud.cpp.

DSPLIB_lud_init_checkParams()

DSPLIB_STATUS DSPLIB_lud_init_checkParams	(	DSPLIB_kernelHandle	handle,
		const DSPLIB_bufParams2D_t *	bufParamsA,
		const DSPLIB_bufParams2D_t *	bufParamsL,
		const DSPLIB_bufParams2D_t *	bufParamsU,
		const DSPLIB_bufParams2D_t *	bufParamsP,
		const DSPLIB_ludInitArgs *	pKerInitArgs
	)

This function checks the validity of the parameters passed to DSPLIB_lud_init function. This function is called with the same parameters as the DSPLIB_lud_init, and this function must be called before the DSPLIB_lud_init is called.

Parameters

[in]	handle	: Active handle to the kernel
[in]	bufParamsA	: Pointer to the structure containing dimensional information of input buffer A
[out]	bufParamsL	: Pointer to the structure containing dimensional information of output buffer L
[out]	bufParamsU	: Pointer to the structure containing dimensional information of output buffer U
[out]	bufParamsP	: Pointer to the structure containing dimensional information of output buffer P
[in]	pKerInitArgs	: Pointer to the structure holding init parameters

Returns

Status value indicating success or failure. Refer to DSPLIB_STATUS.

Remarks

None

Definition at line 34 of file DSPLIB_lud.cpp.

DSPLIB_lud_init()

DSPLIB_STATUS DSPLIB_lud_init	(	DSPLIB_kernelHandle	handle,
		const DSPLIB_bufParams2D_t *	bufParamsA,
		const DSPLIB_bufParams2D_t *	bufParamsL,
		const DSPLIB_bufParams2D_t *	bufParamsU,
		const DSPLIB_bufParams2D_t *	bufParamsP,
		const DSPLIB_ludInitArgs *	pKerInitArgs
	)

This function should be called before the DSPLIB_lud_exec function is called. This function takes care of any one-time operations such as setting up the configuration of required hardware resources such as the streaming engine and streaming address generator. The results of these operations are stored in the handle.

Parameters

[in]	handle	: Active handle to the kernel
[in]	bufParamsA	: Pointer to the structure containing dimensional information of input buffer A
[out]	bufParamsL	: Pointer to the structure containing dimensional information of output buffer L
[out]	bufParamsU	: Pointer to the structure containing dimensional information of output buffer U
[out]	bufParamsP	: Pointer to the structure containing dimensional information of output buffer P
[in]	pKerInitArgs	: Pointer to the structure holding init parameters

Returns

Status value indicating success or failure. Refer to DSPLIB_STATUS.

Remarks

Application is expected to provide a valid handle.

Definition at line 103 of file DSPLIB_lud.cpp.

DSPLIB_lud_exec_checkParams()

DSPLIB_STATUS DSPLIB_lud_exec_checkParams	(	DSPLIB_kernelHandle	handle,
		const void *restrict	pA,
		const void *restrict	pL,
		const void *restrict	pU,
		const void *restrict	pP
	)

This function checks the validity of the parameters passed to DSPLIB_lud_exec function. This function is called with the same parameters as the DSPLIB_lud_exec, and this function must be called before the DSPLIB_lud_exec is called.

Parameters

[in]	handle	: Active handle to the kernel
[in]	pA	: Pointer to matrix A
[out]	pL	: Pointer to lower triangular matrix L
[out]	pU	: Pointer to upper triangular matrix U
[out]	pP	: Pointer to permutation matrix P

Returns

Status value indicating success or failure. Refer to DSPLIB_STATUS.

Remarks

None

Definition at line 82 of file DSPLIB_lud.cpp.

DSPLIB_lud_exec()

DSPLIB_STATUS DSPLIB_lud_exec	(	DSPLIB_kernelHandle	handle,
		void *restrict	pA,
		void *restrict	pL,
		void *restrict	pU,
		void *restrict	pP
	)

This function is the main kernel compute function.

Please refer to details under DSPLIB_lud_exec

Parameters

[in]	handle	: Active handle to the kernel
[in]	pA	: Pointer to matrix A
[out]	pL	: Pointer to lower triangular matrix L
[out]	pU	: Pointer to upper triangular matrix U
[out]	pP	: Pointer to permutation matrix P

Memory Requirements

Buffer	dimY	dimX	Comments
pA	M	M	Input Square Matrix
pL	M	M	Output Lower Triangular Matrix
pU	M	M	Output Upper Triangular Matrix
pP	M	M	Output Permutation Matrix (Data Type = uint16_t)

Returns

Status value indicating success or failure. Refer to DSPLIB_STATUS.

Assumptions:

• None

Performance Considerations:

For best performance,

• The input and output data buffers are expected to be in L2 memory
• The buffer pointers are assumed to be 64-byte aligned
• Ensure that the starting point of adjacent rows in a 2-D matrix are allocated from different banks in L2 memory with the help of memory padding.

Remarks

Before calling this function, application is expected to call DSPLIB_lud_init and DSPLIB_lud_exec_checkParams functions. This ensures resource configuration and error checks are done only once for several invocations of this function.

Definition at line 154 of file DSPLIB_lud.cpp.