summaryrefslogtreecommitdiff
path: root/hid-dials/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_min_q7.c
blob: ac9660330a8e813660c5d172201114035260b09f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
/* ----------------------------------------------------------------------
 * Project:      CMSIS DSP Library
 * Title:        arm_min_q7.c
 * Description:  Minimum value of a Q7 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 "arm_math.h"

/**
 * @ingroup groupStats
 */


/**
 * @addtogroup Min
 * @{
 */


/**
 * @brief Minimum value of a Q7 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_q7(
  q7_t * pSrc,
  uint32_t blockSize,
  q7_t * pResult,
  uint32_t * pIndex)
{
#if defined (ARM_MATH_DSP)
  /* Run the below code for Cortex-M4 and Cortex-M3 */

  q7_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 */

  q7_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
 */