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Removed error on fat32 library, seems now to be able navigate among sectors in...
Removed error on fat32 library, seems now to be able navigate among sectors in both directions. Improved SDLCD drawing performances by almost 1000x.
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arm_mat_mult_fast_q31.c
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/ lib / src / stm32f4 / CPU / CMSIS / DSP_Lib / Source / MatrixFunctions / arm_mat_mult_fast_q31.c
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/* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date: 15. July 2011
* $Revision: V1.0.10
*
* Project: CMSIS DSP Library
* Title: arm_mat_mult_fast_q31.c
*
* Description: Q31 matrix multiplication (fast variant).
*
* Target Processor: Cortex-M4/Cortex-M3
*
* Version 1.0.10 2011/7/15
* Big Endian support added and Merged M0 and M3/M4 Source code.
*
* Version 1.0.3 2010/11/29
* Re-organized the CMSIS folders and updated documentation.
*
* Version 1.0.2 2010/11/11
* Documentation updated.
*
* Version 1.0.1 2010/10/05
* Production release and review comments incorporated.
*
* Version 1.0.0 2010/09/20
* Production release and review comments incorporated.
* -------------------------------------------------------------------- */
#include "arm_math.h"
/**
* @ingroup groupMatrix
*/
/**
* @addtogroup MatrixMult
* @{
*/
/**
* @brief Q31 matrix multiplication (fast variant) for Cortex-M3 and Cortex-M4
* @param[in] *pSrcA points to the first input matrix structure
* @param[in] *pSrcB points to the second input matrix structure
* @param[out] *pDst points to output matrix structure
* @return The function returns either
* <code>ARM_MATH_SIZE_MISMATCH</code> or <code>ARM_MATH_SUCCESS</code> based on the outcome of size checking.
*
* @details
* <b>Scaling and Overflow Behavior:</b>
*
* \par
* The difference between the function arm_mat_mult_q31() and this fast variant is that
* the fast variant use a 32-bit rather than a 64-bit accumulator.
* The result of each 1.31 x 1.31 multiplication is truncated to
* 2.30 format. These intermediate results are accumulated in a 32-bit register in 2.30
* format. Finally, the accumulator is saturated and converted to a 1.31 result.
*
* \par
* The fast version has the same overflow behavior as the standard version but provides
* less precision since it discards the low 32 bits of each multiplication result.
* In order to avoid overflows completely the input signals must be scaled down.
* Scale down one of the input matrices by log2(numColsA) bits to
* avoid overflows, as a total of numColsA additions are computed internally for each
* output element.
*
* \par
* See <code>arm_mat_mult_q31()</code> for a slower implementation of this function
* which uses 64-bit accumulation to provide higher precision.
*/
arm_status arm_mat_mult_fast_q31(
const arm_matrix_instance_q31 * pSrcA,
const arm_matrix_instance_q31 * pSrcB,
arm_matrix_instance_q31 * pDst)
{
q31_t *pIn1 = pSrcA->pData; /* input data matrix pointer A */
q31_t *pIn2 = pSrcB->pData; /* input data matrix pointer B */
q31_t *pInA = pSrcA->pData; /* input data matrix pointer A */
// q31_t *pSrcB = pSrcB->pData; /* input data matrix pointer B */
q31_t *pOut = pDst->pData; /* output data matrix pointer */
q31_t *px; /* Temporary output data matrix pointer */
q31_t sum; /* Accumulator */
uint16_t numRowsA = pSrcA->numRows; /* number of rows of input matrix A */
uint16_t numColsB = pSrcB->numCols; /* number of columns of input matrix B */
uint16_t numColsA = pSrcA->numCols; /* number of columns of input matrix A */
uint16_t col, i = 0u, j, row = numRowsA, colCnt; /* loop counters */
arm_status status; /* status of matrix multiplication */
#ifdef ARM_MATH_MATRIX_CHECK
/* Check for matrix mismatch condition */
if((pSrcA->numCols != pSrcB->numRows) ||
(pSrcA->numRows != pDst->numRows) || (pSrcB->numCols != pDst->numCols))
{
/* Set status as ARM_MATH_SIZE_MISMATCH */
status = ARM_MATH_SIZE_MISMATCH;
}
else
#endif /* #ifdef ARM_MATH_MATRIX_CHECK */
{
/* The following loop performs the dot-product of each row in pSrcA with each column in pSrcB */
/* row loop */
do
{
/* Output pointer is set to starting address of the row being processed */
px = pOut + i;
/* For every row wise process, the column loop counter is to be initiated */
col = numColsB;
/* For every row wise process, the pIn2 pointer is set
** to the starting address of the pSrcB data */
pIn2 = pSrcB->pData;
j = 0u;
/* column loop */
do
{
/* Set the variable sum, that acts as accumulator, to zero */
sum = 0;
/* Initiate the pointer pIn1 to point to the starting address of pInA */
pIn1 = pInA;
/* Apply loop unrolling and compute 4 MACs simultaneously. */
colCnt = numColsA >> 2;
/* matrix multiplication */
while(colCnt > 0u)
{
/* c(m,n) = a(1,1)*b(1,1) + a(1,2) * b(2,1) + .... + a(m,p)*b(p,n) */
/* Perform the multiply-accumulates */
sum = (q31_t) ((((q63_t) sum << 32) +
((q63_t) * pIn1++ * (*pIn2))) >> 32);
pIn2 += numColsB;
sum = (q31_t) ((((q63_t) sum << 32) +
((q63_t) * pIn1++ * (*pIn2))) >> 32);
pIn2 += numColsB;
sum = (q31_t) ((((q63_t) sum << 32) +
((q63_t) * pIn1++ * (*pIn2))) >> 32);
pIn2 += numColsB;
sum = (q31_t) ((((q63_t) sum << 32) +
((q63_t) * pIn1++ * (*pIn2))) >> 32);
pIn2 += numColsB;
/* Decrement the loop counter */
colCnt--;
}
/* If the columns of pSrcA is not a multiple of 4, compute any remaining output samples here.
** No loop unrolling is used. */
colCnt = numColsA % 0x4u;
while(colCnt > 0u)
{
/* c(m,n) = a(1,1)*b(1,1) + a(1,2) * b(2,1) + .... + a(m,p)*b(p,n) */
/* Perform the multiply-accumulates */
sum = (q31_t) ((((q63_t) sum << 32) +
((q63_t) * pIn1++ * (*pIn2))) >> 32);
pIn2 += numColsB;
/* Decrement the loop counter */
colCnt--;
}
/* Convert the result from 2.30 to 1.31 format and store in destination buffer */
*px++ = sum << 1;
/* Update the pointer pIn2 to point to the starting address of the next column */
j++;
pIn2 = pSrcB->pData + j;
/* Decrement the column loop counter */
col--;
} while(col > 0u);
/* Update the pointer pInA to point to the starting address of the next row */
i = i + numColsB;
pInA = pInA + numColsA;
/* Decrement the row loop counter */
row--;
} while(row > 0u);
/* set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;
}
/* Return to application */
return (status);
}
/**
* @} end of MatrixMult group
*/