pinebuds/platform/cmsis/DSP_Lib/BasicMathFunctions/arm_abs_f32.c
2022-08-15 17:20:27 +08:00

117 lines
2.8 KiB
C

/* ----------------------------------------------------------------------
* Project: CMSIS DSP Library
* Title: arm_abs_f32.c
* Description: Floating-point 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"
#include <math.h>
/**
@ingroup groupMath
*/
/**
@defgroup BasicAbs Vector Absolute Value
Computes the absolute value of a vector on an element-by-element basis.
<pre>
pDst[n] = abs(pSrc[n]), 0 <= n < blockSize.
</pre>
The functions support in-place computation allowing the source and
destination pointers to reference the same memory buffer.
There are separate functions for floating-point, Q7, Q15, and Q31 data types.
*/
/**
@addtogroup BasicAbs
@{
*/
/**
@brief Floating-point 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
*/
void arm_abs_f32(
const float32_t * pSrc,
float32_t * pDst,
uint32_t blockSize)
{
uint32_t blkCnt; /* Loop counter */
#if defined (ARM_MATH_LOOPUNROLL)
/* Loop unrolling: Compute 4 outputs at a time */
blkCnt = blockSize >> 2U;
while (blkCnt > 0U)
{
/* C = |A| */
/* Calculate absolute and store result in destination buffer. */
*pDst++ = fabsf(*pSrc++);
*pDst++ = fabsf(*pSrc++);
*pDst++ = fabsf(*pSrc++);
*pDst++ = fabsf(*pSrc++);
/* 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 and store result in destination buffer. */
*pDst++ = fabsf(*pSrc++);
/* Decrement loop counter */
blkCnt--;
}
}
/**
@} end of BasicAbs group
*/