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/* ----------------------------------------------------------------------    
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* Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
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*    
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* $Date:        19. March 2015
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* $Revision:    V.1.4.5
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*    
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* Project:          CMSIS DSP Library    
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* Title:                arm_abs_f32.c    
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*    
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* Description:  Vector absolute value.    
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*    
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* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
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*  
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*   - Redistributions of source code must retain the above copyright
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*     notice, this list of conditions and the following disclaimer.
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*   - Redistributions in binary form must reproduce the above copyright
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*     notice, this list of conditions and the following disclaimer in
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*     the documentation and/or other materials provided with the
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*     distribution.
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*   - Neither the name of ARM LIMITED nor the names of its contributors
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*     may be used to endorse or promote products derived from this
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*     software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.  
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* ---------------------------------------------------------------------------- */
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#include "arm_math.h"
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#include <math.h>
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/**        
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 * @ingroup groupMath        
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 */
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/**        
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 * @defgroup BasicAbs Vector Absolute Value        
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 *        
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 * Computes the absolute value of a vector on an element-by-element basis.        
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 *        
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 * <pre>        
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 *     pDst[n] = abs(pSrc[n]),   0 <= n < blockSize.        
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 * </pre>        
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 *        
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 * The functions support in-place computation allowing the source and
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 * destination pointers to reference the same memory buffer.
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 * There are separate functions for floating-point, Q7, Q15, and Q31 data types.
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 */
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/**        
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 * @addtogroup BasicAbs        
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 * @{        
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 */
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/**        
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 * @brief Floating-point vector absolute value.        
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 * @param[in]       *pSrc points to the input buffer        
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 * @param[out]      *pDst points to the output buffer        
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 * @param[in]       blockSize number of samples in each vector        
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 * @return none.        
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 */
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void arm_abs_f32(
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  float32_t * pSrc,
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  float32_t * pDst,
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  uint32_t blockSize)
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{
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  uint32_t blkCnt;                               /* loop counter */
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#ifndef ARM_MATH_CM0_FAMILY
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  /* Run the below code for Cortex-M4 and Cortex-M3 */
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  float32_t in1, in2, in3, in4;                  /* temporary variables */
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  /*loop Unrolling */
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  blkCnt = blockSize >> 2u;
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  /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.    
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   ** a second loop below computes the remaining 1 to 3 samples. */
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  while(blkCnt > 0u)
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  {
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    /* C = |A| */
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    /* Calculate absolute and then store the results in the destination buffer. */
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    /* read sample from source */
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    in1 = *pSrc;
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    in2 = *(pSrc + 1);
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    in3 = *(pSrc + 2);
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    /* find absolute value */
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    in1 = fabsf(in1);
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    /* read sample from source */
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    in4 = *(pSrc + 3);
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    /* find absolute value */
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    in2 = fabsf(in2);
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    /* read sample from source */
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    *pDst = in1;
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    /* find absolute value */
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    in3 = fabsf(in3);
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    /* find absolute value */
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    in4 = fabsf(in4);
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    /* store result to destination */
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    *(pDst + 1) = in2;
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    /* store result to destination */
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    *(pDst + 2) = in3;
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    /* store result to destination */
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    *(pDst + 3) = in4;
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    /* Update source pointer to process next sampels */
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    pSrc += 4u;
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    /* Update destination pointer to process next sampels */
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    pDst += 4u;
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    /* Decrement the loop counter */
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    blkCnt--;
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  }
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  /* If the blockSize is not a multiple of 4, compute any remaining output samples here.    
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   ** No loop unrolling is used. */
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  blkCnt = blockSize % 0x4u;
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#else
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  /* Run the below code for Cortex-M0 */
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  /* Initialize blkCnt with number of samples */
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  blkCnt = blockSize;
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#endif /*   #ifndef ARM_MATH_CM0_FAMILY   */
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  while(blkCnt > 0u)
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  {
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    /* C = |A| */
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    /* Calculate absolute and then store the results in the destination buffer. */
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    *pDst++ = fabsf(*pSrc++);
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    /* Decrement the loop counter */
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    blkCnt--;
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  }
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}
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/**        
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 * @} end of BasicAbs group        
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 */