blob: 8ff9e7b5fdc4414fcb76abfd028899dfd3e80c86 (
plain) (
blame)
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
|
/* ----------------------------------------------------------------------
* Project: CMSIS DSP Library
* Title: arm_q31_to_float.c
* Description: Converts the elements of the Q31 vector to floating-point vector
*
* $Date: 18. March 2019
* $Revision: V1.6.0
*
* Target Processor: Cortex-M cores
* -------------------------------------------------------------------- */
/*
* Copyright (C) 2010-2019 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 groupSupport
*/
/**
* @defgroup q31_to_x Convert 32-bit Integer value
*/
/**
@addtogroup q31_to_x
@{
*/
/**
@brief Converts the elements of the Q31 vector to floating-point vector.
@param[in] pSrc points to the Q31 input vector
@param[out] pDst points to the floating-point output vector
@param[in] blockSize number of samples in each vector
@return none
@par Details
The equation used for the conversion process is:
<pre>
pDst[n] = (float32_t) pSrc[n] / 2147483648; 0 <= n < blockSize.
</pre>
*/
#if defined(ARM_MATH_NEON_EXPERIMENTAL)
void arm_q31_to_float(
const q31_t * pSrc,
float32_t * pDst,
uint32_t blockSize)
{
const q31_t *pIn = pSrc; /* Src pointer */
uint32_t blkCnt; /* loop counter */
int32x4_t inV;
float32x4_t outV;
blkCnt = blockSize >> 2U;
/* Compute 4 outputs at a time.
** a second loop below computes the remaining 1 to 3 samples. */
while (blkCnt > 0U)
{
/* C = (float32_t) A / 2147483648 */
/* Convert from q31 to float and then store the results in the destination buffer */
inV = vld1q_s32(pIn);
pIn += 4;
outV = vcvtq_n_f32_s32(inV,31);
vst1q_f32(pDst, outV);
pDst += 4;
/* 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 & 3;
while (blkCnt > 0U)
{
/* C = (float32_t) A / 2147483648 */
/* Convert from q31 to float and then store the results in the destination buffer */
*pDst++ = ((float32_t) * pIn++ / 2147483648.0f);
/* Decrement the loop counter */
blkCnt--;
}
}
#else
void arm_q31_to_float(
const q31_t * pSrc,
float32_t * pDst,
uint32_t blockSize)
{
const q31_t *pIn = pSrc; /* Src pointer */
uint32_t blkCnt; /* loop counter */
#if defined (ARM_MATH_LOOPUNROLL)
/* Loop unrolling */
blkCnt = blockSize >> 2U;
while (blkCnt > 0U)
{
/* C = (float32_t) A / 2147483648 */
/* Convert from q31 to float and store result in destination buffer */
*pDst++ = ((float32_t) *pIn++ / 2147483648.0f);
*pDst++ = ((float32_t) *pIn++ / 2147483648.0f);
*pDst++ = ((float32_t) *pIn++ / 2147483648.0f);
*pDst++ = ((float32_t) *pIn++ / 2147483648.0f);
/* Decrement loop counter */
blkCnt--;
}
/* Loop unrolling: Compute remaining outputs */
blkCnt = blockSize % 0x4U;
#else
/* Initialize blkCnt with number of samples */
blkCnt = blockSize;
#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
while (blkCnt > 0U)
{
/* C = (float32_t) A / 2147483648 */
/* Convert from q31 to float and store result in destination buffer */
*pDst++ = ((float32_t) *pIn++ / 2147483648.0f);
/* Decrement loop counter */
blkCnt--;
}
}
#endif /* #if defined(ARM_MATH_NEON) */
/**
@} end of q31_to_x group
*/
|
