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| 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_f32.c |
| 9 | +* |
| 10 | +* Description: 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 | +#include <math.h> |
| 43 | + |
| 44 | +/** |
| 45 | + * @ingroup groupMath |
| 46 | + */ |
| 47 | + |
| 48 | +/** |
| 49 | + * @defgroup BasicAbs Vector Absolute Value |
| 50 | + * |
| 51 | + * Computes the absolute value of a vector on an element-by-element basis. |
| 52 | + * |
| 53 | + * <pre> |
| 54 | + * pDst[n] = abs(pSrc[n]), 0 <= n < blockSize. |
| 55 | + * </pre> |
| 56 | + * |
| 57 | + * The functions support in-place computation allowing the source and |
| 58 | + * destination pointers to reference the same memory buffer. |
| 59 | + * There are separate functions for floating-point, Q7, Q15, and Q31 data types. |
| 60 | + */ |
| 61 | + |
| 62 | +/** |
| 63 | + * @addtogroup BasicAbs |
| 64 | + * @{ |
| 65 | + */ |
| 66 | + |
| 67 | +/** |
| 68 | + * @brief Floating-point vector absolute value. |
| 69 | + * @param[in] *pSrc points to the input buffer |
| 70 | + * @param[out] *pDst points to the output buffer |
| 71 | + * @param[in] blockSize number of samples in each vector |
| 72 | + * @return none. |
| 73 | + */ |
| 74 | + |
| 75 | +void arm_abs_f32( |
| 76 | + float32_t * pSrc, |
| 77 | + float32_t * pDst, |
| 78 | + uint32_t blockSize) |
| 79 | +{ |
| 80 | + uint32_t blkCnt; /* loop counter */ |
| 81 | + |
| 82 | +#ifndef ARM_MATH_CM0_FAMILY |
| 83 | + |
| 84 | + /* Run the below code for Cortex-M4 and Cortex-M3 */ |
| 85 | + float32_t in1, in2, in3, in4; /* temporary variables */ |
| 86 | + |
| 87 | + /*loop Unrolling */ |
| 88 | + blkCnt = blockSize >> 2u; |
| 89 | + |
| 90 | + /* First part of the processing with loop unrolling. Compute 4 outputs at a time. |
| 91 | + ** a second loop below computes the remaining 1 to 3 samples. */ |
| 92 | + while(blkCnt > 0u) |
| 93 | + { |
| 94 | + /* C = |A| */ |
| 95 | + /* Calculate absolute and then store the results in the destination buffer. */ |
| 96 | + /* read sample from source */ |
| 97 | + in1 = *pSrc; |
| 98 | + in2 = *(pSrc + 1); |
| 99 | + in3 = *(pSrc + 2); |
| 100 | + |
| 101 | + /* find absolute value */ |
| 102 | + in1 = fabsf(in1); |
| 103 | + |
| 104 | + /* read sample from source */ |
| 105 | + in4 = *(pSrc + 3); |
| 106 | + |
| 107 | + /* find absolute value */ |
| 108 | + in2 = fabsf(in2); |
| 109 | + |
| 110 | + /* read sample from source */ |
| 111 | + *pDst = in1; |
| 112 | + |
| 113 | + /* find absolute value */ |
| 114 | + in3 = fabsf(in3); |
| 115 | + |
| 116 | + /* find absolute value */ |
| 117 | + in4 = fabsf(in4); |
| 118 | + |
| 119 | + /* store result to destination */ |
| 120 | + *(pDst + 1) = in2; |
| 121 | + |
| 122 | + /* store result to destination */ |
| 123 | + *(pDst + 2) = in3; |
| 124 | + |
| 125 | + /* store result to destination */ |
| 126 | + *(pDst + 3) = in4; |
| 127 | + |
| 128 | + |
| 129 | + /* Update source pointer to process next sampels */ |
| 130 | + pSrc += 4u; |
| 131 | + |
| 132 | + /* Update destination pointer to process next sampels */ |
| 133 | + pDst += 4u; |
| 134 | + |
| 135 | + /* Decrement the loop counter */ |
| 136 | + blkCnt--; |
| 137 | + } |
| 138 | + |
| 139 | + /* If the blockSize is not a multiple of 4, compute any remaining output samples here. |
| 140 | + ** No loop unrolling is used. */ |
| 141 | + blkCnt = blockSize % 0x4u; |
| 142 | + |
| 143 | +#else |
| 144 | + |
| 145 | + /* Run the below code for Cortex-M0 */ |
| 146 | + |
| 147 | + /* Initialize blkCnt with number of samples */ |
| 148 | + blkCnt = blockSize; |
| 149 | + |
| 150 | +#endif /* #ifndef ARM_MATH_CM0_FAMILY */ |
| 151 | + |
| 152 | + while(blkCnt > 0u) |
| 153 | + { |
| 154 | + /* C = |A| */ |
| 155 | + /* Calculate absolute and then store the results in the destination buffer. */ |
| 156 | + *pDst++ = fabsf(*pSrc++); |
| 157 | + |
| 158 | + /* Decrement the loop counter */ |
| 159 | + blkCnt--; |
| 160 | + } |
| 161 | +} |
| 162 | + |
| 163 | +/** |
| 164 | + * @} end of BasicAbs group |
| 165 | + */ |
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