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Sem-dma/Drivers/CMSIS/DSP/Source/MatrixFunctions/arm_mat_sub_q15.c
Julien Chevalley 902141e8b6 Initial commit
2023-12-11 14:43:05 +01:00

149 lines
4.4 KiB
C

/* ----------------------------------------------------------------------
* Project: CMSIS DSP Library
* Title: arm_mat_sub_q15.c
* Description: Q15 Matrix subtraction
*
* $Date: 27. January 2017
* $Revision: V.1.5.1
*
* Target Processor: Cortex-M cores
* -------------------------------------------------------------------- */
/*
* Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
*
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the License); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an AS IS BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "arm_math.h"
/**
* @ingroup groupMatrix
*/
/**
* @addtogroup MatrixSub
* @{
*/
/**
* @brief Q15 matrix subtraction.
* @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.
*
* <b>Scaling and Overflow Behavior:</b>
* \par
* The function uses saturating arithmetic.
* Results outside of the allowable Q15 range [0x8000 0x7FFF] will be saturated.
*/
arm_status arm_mat_sub_q15(
const arm_matrix_instance_q15 * pSrcA,
const arm_matrix_instance_q15 * pSrcB,
arm_matrix_instance_q15 * pDst)
{
q15_t *pInA = pSrcA->pData; /* input data matrix pointer A */
q15_t *pInB = pSrcB->pData; /* input data matrix pointer B */
q15_t *pOut = pDst->pData; /* output data matrix pointer */
uint32_t numSamples; /* total number of elements in the matrix */
uint32_t blkCnt; /* loop counters */
arm_status status; /* status of matrix subtraction */
#ifdef ARM_MATH_MATRIX_CHECK
/* Check for matrix mismatch condition */
if ((pSrcA->numRows != pSrcB->numRows) ||
(pSrcA->numCols != pSrcB->numCols) ||
(pSrcA->numRows != pDst->numRows) || (pSrcA->numCols != pDst->numCols))
{
/* Set status as ARM_MATH_SIZE_MISMATCH */
status = ARM_MATH_SIZE_MISMATCH;
}
else
#endif /* #ifdef ARM_MATH_MATRIX_CHECK */
{
/* Total number of samples in the input matrix */
numSamples = (uint32_t) pSrcA->numRows * pSrcA->numCols;
#if defined (ARM_MATH_DSP)
/* Run the below code for Cortex-M4 and Cortex-M3 */
/* Apply loop unrolling */
blkCnt = numSamples >> 2U;
/* First part of the processing with loop unrolling. Compute 4 outputs at a time.
** a second loop below computes the remaining 1 to 3 samples. */
while (blkCnt > 0U)
{
/* C(m,n) = A(m,n) - B(m,n) */
/* Subtract, Saturate and then store the results in the destination buffer. */
*__SIMD32(pOut)++ = __QSUB16(*__SIMD32(pInA)++, *__SIMD32(pInB)++);
*__SIMD32(pOut)++ = __QSUB16(*__SIMD32(pInA)++, *__SIMD32(pInB)++);
/* Decrement the loop counter */
blkCnt--;
}
/* If the blockSize is not a multiple of 4, compute any remaining output samples here.
** No loop unrolling is used. */
blkCnt = numSamples % 0x4U;
while (blkCnt > 0U)
{
/* C(m,n) = A(m,n) - B(m,n) */
/* Subtract and then store the results in the destination buffer. */
*pOut++ = (q15_t) __QSUB16(*pInA++, *pInB++);
/* Decrement the loop counter */
blkCnt--;
}
#else
/* Run the below code for Cortex-M0 */
/* Initialize blkCnt with number of samples */
blkCnt = numSamples;
while (blkCnt > 0U)
{
/* C(m,n) = A(m,n) - B(m,n) */
/* Subtract and then store the results in the destination buffer. */
*pOut++ = (q15_t) __SSAT(((q31_t) * pInA++ - *pInB++), 16);
/* Decrement the loop counter */
blkCnt--;
}
#endif /* #if defined (ARM_MATH_DSP) */
/* Set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;
}
/* Return to application */
return (status);
}
/**
* @} end of MatrixSub group
*/