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Official ARM version: v5.6.0

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rihab kouki 2020-07-28 11:24:49 +01:00
parent 9f95ff5b6b
commit 96d6da4e25
2939 changed files with 339304 additions and 113320 deletions
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111
DSP/Source/BasicMathFunctions/arm_negate_q15.c
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@ -3,13 +3,13 @@
* Title: arm_negate_q15.c
* Description: Negates Q15 vectors
*
* $Date: 27. January 2017
* $Revision: V.1.5.1
* $Date: 18. March 2019
* $Revision: V1.6.0
*
* Target Processor: Cortex-M cores
* -------------------------------------------------------------------- */
/*
* Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
* Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
*
* SPDX-License-Identifier: Apache-2.0
*
@ -29,103 +29,98 @@
#include "arm_math.h"
/**
* @ingroup groupMath
@ingroup groupMath
*/
/**
* @addtogroup negate
* @{
@addtogroup BasicNegate
@{
*/
/**
* @brief Negates the elements of a Q15 vector.
* @param[in] *pSrc points to the input vector
* @param[out] *pDst points to the output vector
* @param[in] blockSize number of samples in the vector
* @return none.
*
* \par Conditions for optimum performance
* Input and output buffers should be aligned by 32-bit
*
*
* <b>Scaling and Overflow Behavior:</b>
* \par
* The function uses saturating arithmetic.
* The Q15 value -1 (0x8000) will be saturated to the maximum allowable positive value 0x7FFF.
@brief Negates the elements of a Q15 vector.
@param[in] pSrc points to the input vector.
@param[out] pDst points to the output vector.
@param[in] blockSize number of samples in each vector.
@return none
@par Conditions for optimum performance
Input and output buffers should be aligned by 32-bit
@par Scaling and Overflow Behavior
The function uses saturating arithmetic.
The Q15 value -1 (0x8000) is saturated to the maximum allowable positive value 0x7FFF.
*/
void arm_negate_q15(
q15_t * pSrc,
q15_t * pDst,
uint32_t blockSize)
const q15_t * pSrc,
q15_t * pDst,
uint32_t blockSize)
{
uint32_t blkCnt; /* loop counter */
q15_t in;
uint32_t blkCnt; /* Loop counter */
q15_t in; /* Temporary input variable */
#if defined (ARM_MATH_LOOPUNROLL)
#if defined (ARM_MATH_DSP)
q31_t in1; /* Temporary input variables */
#endif
/* Run the below code for Cortex-M4 and Cortex-M3 */
q31_t in1, in2; /* Temporary variables */
/*loop Unrolling */
/* Loop unrolling: Compute 4 outputs at a time */
blkCnt = blockSize >> 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 = -A */
/* Read two inputs at a time */
in1 = _SIMD32_OFFSET(pSrc);
in2 = _SIMD32_OFFSET(pSrc + 2);
/* negate two samples at a time */
in1 = __QSUB16(0, in1);
#if defined (ARM_MATH_DSP)
/* Negate and store result in destination buffer (2 samples at a time). */
in1 = read_q15x2_ia ((q15_t **) &pSrc);
write_q15x2_ia (&pDst, __QSUB16(0, in1));
/* negate two samples at a time */
in2 = __QSUB16(0, in2);
in1 = read_q15x2_ia ((q15_t **) &pSrc);
write_q15x2_ia (&pDst, __QSUB16(0, in1));
#else
in = *pSrc++;
*pDst++ = (in == (q15_t) 0x8000) ? (q15_t) 0x7fff : -in;
/* store the result to destination 2 samples at a time */
_SIMD32_OFFSET(pDst) = in1;
/* store the result to destination 2 samples at a time */
_SIMD32_OFFSET(pDst + 2) = in2;
in = *pSrc++;
*pDst++ = (in == (q15_t) 0x8000) ? (q15_t) 0x7fff : -in;
in = *pSrc++;
*pDst++ = (in == (q15_t) 0x8000) ? (q15_t) 0x7fff : -in;
/* update pointers to process next samples */
pSrc += 4U;
pDst += 4U;
in = *pSrc++;
*pDst++ = (in == (q15_t) 0x8000) ? (q15_t) 0x7fff : -in;
#endif
/* Decrement the loop counter */
/* Decrement loop counter */
blkCnt--;
}
/* If the blockSize is not a multiple of 4, compute any remaining output samples here.
** No loop unrolling is used. */
/* Loop unrolling: Compute remaining outputs */
blkCnt = blockSize % 0x4U;
#else
/* Run the below code for Cortex-M0 */
/* Initialize blkCnt with number of samples */
blkCnt = blockSize;
#endif /* #if defined (ARM_MATH_DSP) */
#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
while (blkCnt > 0U)
{
/* C = -A */
/* Negate and then store the result in the destination buffer. */
in = *pSrc++;
*pDst++ = (in == (q15_t) 0x8000) ? 0x7fff : -in;
/* Decrement the loop counter */
/* Negate and store result in destination buffer. */
in = *pSrc++;
*pDst++ = (in == (q15_t) 0x8000) ? (q15_t) 0x7fff : -in;
/* Decrement loop counter */
blkCnt--;
}
}
/**
* @} end of negate group
@} end of BasicNegate group
*/