text: /* ----------------------------------------------------------------------
  * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
  *
  * $Date: 16/10/14 6:01p $Revision:  V.1.4.5
  *
  * Project:      CMSIS DSP Library
  * Title:        arm_scale_f32.c
  *
  * Description:  Multiplies a floating-point vector by a scalar.
  *
  * 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,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.
  * ---------------------------------------------------------------------------- */
  
  #include "arm_math.h"
  
  /**
   * @ingroup groupMath
   */
  
  /**
   * @defgroup scale Vector Scale
   *
   * Multiply a vector by a scalar value.  For floating-point data, the algorithm used is:
   *
   * <pre>
   *     pDst[n] = pSrc[n] * scale,   0 <= n < blockSize.
   * </pre>
   *
   * In the fixed-point Q7, Q15, and Q31 functions, <code>scale</code> is represented by
   * a fractional multiplication <code>scaleFract</code> and an arithmetic shift <code>shift</code>.
   * The shift allows the gain of the scaling operation to exceed 1.0.
   * The algorithm used with fixed-point data is:
   *
   * <pre>
   *     pDst[n] = (pSrc[n] * scaleFract) << shift,   0 <= n < blockSize.
   * </pre>
   *
   * The overall scale factor applied to the fixed-point data is
   * <pre>
   *     scale = scaleFract * 2^shift.
   * </pre>
   *
   * The functions support in-place computation allowing the source and destination
   * pointers to reference the same memory buffer.
   */
  
  /**
   * @addtogroup scale
   * @{
   */
  
  /**
   * @brief Multiplies a floating-point vector by a scalar.
   * @param[in]       *pSrc points to the input vector
   * @param[in]       scale scale factor to be applied
   * @param[out]      *pDst points to the output vector
   * @param[in]       blockSize number of samples in the vector
   * @return none.
   */
  
  
  void arm_scale_f32(
      float32_t * pSrc,
      float32_t scale,
      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 variabels */
  
      /*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 * scale */
          /* Scale the input and then store the results in the destination buffer. */
          /* read input samples from source */
          in1 = *pSrc;
          in2 = *(pSrc + 1);
  
          /* multiply with scaling factor */
          in1 = in1 * scale;
  
          /* read input sample from source */
          in3 = *(pSrc + 2);
  
          /* multiply with scaling factor */
          in2 = in2 * scale;
  
          /* read input sample from source */
          in4 = *(pSrc + 3);
  
          /* multiply with scaling factor */
          in3 = in3 * scale;
          in4 = in4 * scale;
          /* store the result to destination */
          *pDst = in1;
          *(pDst + 1) = in2;
          *(pDst + 2) = in3;
          *(pDst + 3) = in4;
  
          /* update pointers to process next samples */
          pSrc += 4u;
          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 * scale */
          /* Scale the input and then store the result in the destination buffer. */
          *pDst++ = (*pSrc++) * scale;
  
          /* Decrement the loop counter */
          blkCnt--;
      }
  }
  
  /**
   * @} end of scale group
   */
  