/* ----------------------------------------------------------------------
* Copyright (C) 2010-2014 ARM Limited. All rights reserved.
*
* $Date: 16/10/14 6:00p $Revision:  V.1.4.5
*
* Project:      CMSIS DSP Library
* Title:        arm_abs_f32.c
*
* Description:  Vector absolute value.
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*   - Redistributions of source code must retain the above copyright
*     notice, this list of conditions and the following disclaimer.
*   - Redistributions in binary form must reproduce the above copyright
*     notice, this list of conditions and the following disclaimer in
*     the documentation and/or other materials provided with the
*     distribution.
*   - Neither the name of ARM LIMITED nor the names of its contributors
*     may be used to endorse or promote products derived from this
*     software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* ---------------------------------------------------------------------------- */

#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 buffer
 * @param[out]      *pDst points to the output buffer
 * @param[in]       blockSize number of samples in each vector
 * @return none.
 */

void arm_abs_f32(
    float32_t * pSrc,
    float32_t * pDst,
    uint32_t blockSize)
{
    uint32_t blkCnt;                               /* loop counter */

#ifndef ARM_MATH_CM0_FAMILY

    /* Run the below code for Cortex-M4 and Cortex-M3 */
    float32_t in1, in2, in3, in4;                  /* temporary variables */

    /*loop Unrolling */
    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| */
        /* Calculate absolute and then store the results in the destination buffer. */
        /* read sample from source */
        in1 = *pSrc;
        in2 = *(pSrc + 1);
        in3 = *(pSrc + 2);

        /* find absolute value */
        in1 = fabsf(in1);

        /* read sample from source */
        in4 = *(pSrc + 3);

        /* find absolute value */
        in2 = fabsf(in2);

        /* read sample from source */
        *pDst = in1;

        /* find absolute value */
        in3 = fabsf(in3);

        /* find absolute value */
        in4 = fabsf(in4);

        /* store result to destination */
        *(pDst + 1) = in2;

        /* store result to destination */
        *(pDst + 2) = in3;

        /* store result to destination */
        *(pDst + 3) = in4;


        /* Update source pointer to process next sampels */
        pSrc += 4u;

        /* Update destination pointer to process next sampels */
        pDst += 4u;

        /* 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 = blockSize % 0x4u;

#else

    /* Run the below code for Cortex-M0 */

    /* Initialize blkCnt with number of samples */
    blkCnt = blockSize;

#endif /*   #ifndef ARM_MATH_CM0_FAMILY   */

    while(blkCnt > 0u)
    {
        /* C = |A| */
        /* Calculate absolute and then store the results in the destination buffer. */
        *pDst++ = fabsf(*pSrc++);

        /* Decrement the loop counter */
        blkCnt--;
    }
}

/**
 * @} end of BasicAbs group
 */
