text: /* ----------------------------------------------------------------------
   * Project:      CMSIS DSP Library
   * Title:        arm_min_q15.c
   * Description:  Minimum value of a Q15 vector
   *
   * $Date:        27. January 2017
   * $Revision:    V.1.5.1
   *
   * Target Processor: Cortex-M cores
   * -------------------------------------------------------------------- */
  /*
   * Copyright (C) 2010-2017 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 "CMSIS_DSP/cmsis_dsp.h"
  
  /**
   * @ingroup groupStats
   */
  
  
  /**
   * @addtogroup Min
   * @{
   */
  
  
  /**
   * @brief Minimum value of a Q15 vector.
   * @param[in]       *pSrc points to the input vector
   * @param[in]       blockSize length of the input vector
   * @param[out]      *pResult minimum value returned here
   * @param[out]      *pIndex index of minimum value returned here
   * @return none.
   */
  
  void arm_min_q15(
    q15_t * pSrc,
    uint32_t blockSize,
    q15_t * pResult,
    uint32_t * pIndex)
  {
  #if defined (ARM_MATH_DSP)
    /* Run the below code for Cortex-M4 and Cortex-M3 */
  
    q15_t minVal1, minVal2, out;                   /* Temporary variables to store the output value. */
    uint32_t blkCnt, outIndex, count;              /* loop counter */
  
    /* Initialise the count value. */
    count = 0u;
    /* Initialise the index value to zero. */
    outIndex = 0u;
    /* Load first input value that act as reference value for comparision */
    out = *pSrc++;
  
    /* Loop unrolling */
    blkCnt = (blockSize - 1u) >> 2u;
  
    while (blkCnt > 0u)
    {
      /* Initialize minVal to the next consecutive values one by one */
      minVal1 = *pSrc++;
      minVal2 = *pSrc++;
  
      /* compare for the minimum value */
      if (out > minVal1)
      {
        /* Update the minimum value and its index */
        out = minVal1;
        outIndex = count + 1u;
      }
  
      /* compare for the minimum value */
      if (out > minVal2)
      {
        /* Update the minimum value and its index */
        out = minVal2;
        outIndex = count + 2u;
      }
  
      /* Initialize minVal to the next consecutive values one by one */
      minVal1 = *pSrc++;
      minVal2 = *pSrc++;
  
      /* compare for the minimum value */
      if (out > minVal1)
      {
        /* Update the minimum value and its index */
        out = minVal1;
        outIndex = count + 3u;
      }
  
      /* compare for the minimum value */
      if (out > minVal2)
      {
        /* Update the minimum value and its index */
        out = minVal2;
        outIndex = count + 4u;
      }
  
      count += 4u;
  
      /* Decrement the loop counter */
      blkCnt--;
    }
  
    /* if (blockSize - 1u) is not multiple of 4 */
    blkCnt = (blockSize - 1u) % 4u;
  
  #else
    /* Run the below code for Cortex-M0 */
  
    q15_t minVal1, out;                            /* Temporary variables to store the output value. */
    uint32_t blkCnt, outIndex;                     /* loop counter */
  
    /* Initialise the index value to zero. */
    outIndex = 0u;
    /* Load first input value that act as reference value for comparision */
    out = *pSrc++;
  
    blkCnt = (blockSize - 1u);
  
  #endif /* #if defined (ARM_MATH_DSP) */
  
    while (blkCnt > 0u)
    {
      /* Initialize minVal to the next consecutive values one by one */
      minVal1 = *pSrc++;
  
      /* compare for the minimum value */
      if (out > minVal1)
      {
        /* Update the minimum value and it's index */
        out = minVal1;
        outIndex = blockSize - blkCnt;
      }
  
      /* Decrement the loop counter */
      blkCnt--;
    }
  
    /* Store the minimum value and it's index into destination pointers */
    *pResult = out;
    *pIndex = outIndex;
  }
  
  /**
   * @} end of Min group
   */
  