Mercurial > pub > halpp

comparison f103c8/Drivers/CMSIS/DSP_Lib/Source/BasicMathFunctions/arm_abs_q31.c @ 2:0c59e7a7782a

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Working on GPIO and RCC
author cin
date Mon, 16 Jan 2017 11:04:47 +0300
parents
children
comparison
equal deleted inserted replaced
1:a0b14b11ad9f 2:0c59e7a7782a
1 /* ----------------------------------------------------------------------
2 * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
3 *
4 * $Date: 19. March 2015
5 * $Revision: V.1.4.5
6 *
7 * Project: CMSIS DSP Library
8 * Title: arm_abs_q31.c
9 *
10 * Description: Q31 vector absolute value.
11 *
12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions
16 * are met:
17 * - Redistributions of source code must retain the above copyright
18 * notice, this list of conditions and the following disclaimer.
19 * - Redistributions in binary form must reproduce the above copyright
20 * notice, this list of conditions and the following disclaimer in
21 * the documentation and/or other materials provided with the
22 * distribution.
23 * - Neither the name of ARM LIMITED nor the names of its contributors
24 * may be used to endorse or promote products derived from this
25 * software without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
38 * POSSIBILITY OF SUCH DAMAGE.
39 * -------------------------------------------------------------------- */
40
41 #include "arm_math.h"
42
43 /**
44 * @ingroup groupMath
45 */
46
47 /**
48 * @addtogroup BasicAbs
49 * @{
50 */
51
52
53 /**
54 * @brief Q31 vector absolute value.
55 * @param[in] *pSrc points to the input buffer
56 * @param[out] *pDst points to the output buffer
57 * @param[in] blockSize number of samples in each vector
58 * @return none.
59 *
60 * <b>Scaling and Overflow Behavior:</b>
61 * \par
62 * The function uses saturating arithmetic.
63 * The Q31 value -1 (0x80000000) will be saturated to the maximum allowable positive value 0x7FFFFFFF.
64 */
65
66 void arm_abs_q31(
67 q31_t * pSrc,
68 q31_t * pDst,
69 uint32_t blockSize)
70 {
71 uint32_t blkCnt; /* loop counter */
72 q31_t in; /* Input value */
73
74 #ifndef ARM_MATH_CM0_FAMILY
75
76 /* Run the below code for Cortex-M4 and Cortex-M3 */
77 q31_t in1, in2, in3, in4;
78
79 /*loop Unrolling */
80 blkCnt = blockSize >> 2u;
81
82 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
83 ** a second loop below computes the remaining 1 to 3 samples. */
84 while(blkCnt > 0u)
85 {
86 /* C = |A| */
87 /* Calculate absolute of input (if -1 then saturated to 0x7fffffff) and then store the results in the destination buffer. */
88 in1 = *pSrc++;
89 in2 = *pSrc++;
90 in3 = *pSrc++;
91 in4 = *pSrc++;
92
93 *pDst++ = (in1 > 0) ? in1 : (q31_t)__QSUB(0, in1);
94 *pDst++ = (in2 > 0) ? in2 : (q31_t)__QSUB(0, in2);
95 *pDst++ = (in3 > 0) ? in3 : (q31_t)__QSUB(0, in3);
96 *pDst++ = (in4 > 0) ? in4 : (q31_t)__QSUB(0, in4);
97
98 /* Decrement the loop counter */
99 blkCnt--;
100 }
101
102 /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
103 ** No loop unrolling is used. */
104 blkCnt = blockSize % 0x4u;
105
106 #else
107
108 /* Run the below code for Cortex-M0 */
109
110 /* Initialize blkCnt with number of samples */
111 blkCnt = blockSize;
112
113 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
114
115 while(blkCnt > 0u)
116 {
117 /* C = |A| */
118 /* Calculate absolute value of the input (if -1 then saturated to 0x7fffffff) and then store the results in the destination buffer. */
119 in = *pSrc++;
120 *pDst++ = (in > 0) ? in : ((in == INT32_MIN) ? INT32_MAX : -in);
121
122 /* Decrement the loop counter */
123 blkCnt--;
124 }
125
126 }
127
128 /**
129 * @} end of BasicAbs group
130 */