blob: cb8a08fe00ca64fdd361a6986300a249e7d7ce06 (
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
|
/*
* Copyright (C) 2010-2020 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.
*/
/* ----------------------------------------------------------------------
* Project: CMSIS NN Library
* Title: arm_nn_activations_q15.c
* Description: Q15 neural network activation function using direct table look-up
*
* $Date: 09. October 2020
* $Revision: V.1.0.1
*
* Target Processor: Cortex-M cores
*
* -------------------------------------------------------------------- */
#include "arm_nn_tables.h"
#include "arm_nnfunctions.h"
/**
* @ingroup groupNN
*/
/**
* @addtogroup Acti
* @{
*/
/**
* @brief neural network activation function using direct table look-up
*
* @note Refer header file for details.
*
*/
void arm_nn_activations_direct_q15(q15_t *data, uint16_t size, uint16_t int_width, arm_nn_activation_type type)
{
uint16_t i = size;
q15_t *pIn = data;
q15_t *pOut = data;
uint16_t shift_size = 8 + 3 - int_width;
uint32_t bit_mask = 0x7FF >> int_width;
uint32_t full_frac = bit_mask + 1;
const q15_t *lookup_table;
switch (type)
{
case ARM_SIGMOID:
lookup_table = sigmoidTable_q15;
break;
case ARM_TANH:
default:
lookup_table = tanhTable_q15;
break;
}
while (i)
{
q15_t out;
q15_t in = *pIn++;
q15_t frac = (uint32_t)in & bit_mask;
q15_t value = lookup_table[(uint8_t)(in >> shift_size)];
if ((in >> shift_size) != 0x7f)
{
q15_t value2 = lookup_table[(uint8_t)(1 + ((uint8_t)(in >> shift_size)))];
/* doing the interpolation here for better accuracy */
out = ((q31_t)(full_frac - frac) * value + (q31_t)value2 * frac) >> shift_size;
}
else
{
/* the largest positive value does not have a right side for linear interpolation */
out = value;
}
*pOut++ = out;
i--;
}
}
/**
* @} end of Acti group
*/
|
