131 lines
3.5 KiB
C
131 lines
3.5 KiB
C
/* ----------------------------------------------------------------------
|
|
* Project: CMSIS DSP Library
|
|
* Title: arm_abs_q7.c
|
|
* Description: Q7 vector absolute value
|
|
*
|
|
* $Date: 18. March 2019
|
|
* $Revision: V1.6.0
|
|
*
|
|
* Target Processor: Cortex-M cores
|
|
* -------------------------------------------------------------------- */
|
|
/*
|
|
* Copyright (C) 2010-2019 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 groupMath
|
|
*/
|
|
|
|
/**
|
|
@addtogroup BasicAbs
|
|
@{
|
|
*/
|
|
|
|
/**
|
|
@brief Q7 vector absolute value.
|
|
@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 Q7 value -1 (0x80) will be saturated to the maximum
|
|
allowable positive value 0x7F.
|
|
*/
|
|
|
|
void arm_abs_q7(const q7_t *pSrc, q7_t *pDst, uint32_t blockSize) {
|
|
uint32_t blkCnt; /* Loop counter */
|
|
q7_t in; /* Temporary input variable */
|
|
|
|
#if defined(ARM_MATH_LOOPUNROLL)
|
|
|
|
/* Loop unrolling: Compute 4 outputs at a time */
|
|
blkCnt = blockSize >> 2U;
|
|
|
|
while (blkCnt > 0U) {
|
|
/* C = |A| */
|
|
|
|
/* Calculate absolute of input (if -1 then saturated to 0x7f) and store
|
|
* result in destination buffer. */
|
|
in = *pSrc++;
|
|
#if defined(ARM_MATH_DSP)
|
|
*pDst++ = (in > 0) ? in : (q7_t)__QSUB(0, in);
|
|
#else
|
|
*pDst++ = (in > 0) ? in : ((in == (q7_t)0x80) ? (q7_t)0x7f : -in);
|
|
#endif
|
|
|
|
in = *pSrc++;
|
|
#if defined(ARM_MATH_DSP)
|
|
*pDst++ = (in > 0) ? in : (q7_t)__QSUB(0, in);
|
|
#else
|
|
*pDst++ = (in > 0) ? in : ((in == (q7_t)0x80) ? (q7_t)0x7f : -in);
|
|
#endif
|
|
|
|
in = *pSrc++;
|
|
#if defined(ARM_MATH_DSP)
|
|
*pDst++ = (in > 0) ? in : (q7_t)__QSUB(0, in);
|
|
#else
|
|
*pDst++ = (in > 0) ? in : ((in == (q7_t)0x80) ? (q7_t)0x7f : -in);
|
|
#endif
|
|
|
|
in = *pSrc++;
|
|
#if defined(ARM_MATH_DSP)
|
|
*pDst++ = (in > 0) ? in : (q7_t)__QSUB(0, in);
|
|
#else
|
|
*pDst++ = (in > 0) ? in : ((in == (q7_t)0x80) ? (q7_t)0x7f : -in);
|
|
#endif
|
|
|
|
/* Decrement loop counter */
|
|
blkCnt--;
|
|
}
|
|
|
|
/* Loop unrolling: Compute remaining outputs */
|
|
blkCnt = blockSize % 0x4U;
|
|
|
|
#else
|
|
|
|
/* Initialize blkCnt with number of samples */
|
|
blkCnt = blockSize;
|
|
|
|
#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
|
|
|
|
while (blkCnt > 0U) {
|
|
/* C = |A| */
|
|
|
|
/* Calculate absolute of input (if -1 then saturated to 0x7f) and store
|
|
* result in destination buffer. */
|
|
in = *pSrc++;
|
|
#if defined(ARM_MATH_DSP)
|
|
*pDst++ = (in > 0) ? in : (q7_t)__QSUB(0, in);
|
|
#else
|
|
*pDst++ = (in > 0) ? in : ((in == (q7_t)0x80) ? (q7_t)0x7f : -in);
|
|
#endif
|
|
|
|
/* Decrement loop counter */
|
|
blkCnt--;
|
|
}
|
|
}
|
|
|
|
/**
|
|
@} end of BasicAbs group
|
|
*/
|