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cmsis_dsp/BasicMathFunctions/arm_scale_f32.c@5:3762170b6d4d, 2015-11-20 (annotated)
- Committer:
- mbed_official
- Date:
- Fri Nov 20 08:45:18 2015 +0000
- Revision:
- 5:3762170b6d4d
- Parent:
- 3:7a284390b0ce
Synchronized with git revision 2eb940b9a73af188d3004a2575fdfbb05febe62b
Full URL: https://github.com/mbedmicro/mbed/commit/2eb940b9a73af188d3004a2575fdfbb05febe62b/
Added option to build rpc library. closes #1426
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| emilmont | 1:fdd22bb7aa52 | 1 | /* ---------------------------------------------------------------------- |
| mbed_official | 5:3762170b6d4d | 2 | * Copyright (C) 2010-2014 ARM Limited. All rights reserved. |
| emilmont | 1:fdd22bb7aa52 | 3 | * |
| mbed_official | 5:3762170b6d4d | 4 | * $Date: 19. March 2015 |
| mbed_official | 5:3762170b6d4d | 5 | * $Revision: V.1.4.5 |
| emilmont | 1:fdd22bb7aa52 | 6 | * |
| emilmont | 2:da51fb522205 | 7 | * Project: CMSIS DSP Library |
| emilmont | 2:da51fb522205 | 8 | * Title: arm_scale_f32.c |
| emilmont | 1:fdd22bb7aa52 | 9 | * |
| emilmont | 2:da51fb522205 | 10 | * Description: Multiplies a floating-point vector by a scalar. |
| emilmont | 1:fdd22bb7aa52 | 11 | * |
| emilmont | 1:fdd22bb7aa52 | 12 | * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 |
| emilmont | 1:fdd22bb7aa52 | 13 | * |
| mbed_official | 3:7a284390b0ce | 14 | * Redistribution and use in source and binary forms, with or without |
| mbed_official | 3:7a284390b0ce | 15 | * modification, are permitted provided that the following conditions |
| mbed_official | 3:7a284390b0ce | 16 | * are met: |
| mbed_official | 3:7a284390b0ce | 17 | * - Redistributions of source code must retain the above copyright |
| mbed_official | 3:7a284390b0ce | 18 | * notice, this list of conditions and the following disclaimer. |
| mbed_official | 3:7a284390b0ce | 19 | * - Redistributions in binary form must reproduce the above copyright |
| mbed_official | 3:7a284390b0ce | 20 | * notice, this list of conditions and the following disclaimer in |
| mbed_official | 3:7a284390b0ce | 21 | * the documentation and/or other materials provided with the |
| mbed_official | 3:7a284390b0ce | 22 | * distribution. |
| mbed_official | 3:7a284390b0ce | 23 | * - Neither the name of ARM LIMITED nor the names of its contributors |
| mbed_official | 3:7a284390b0ce | 24 | * may be used to endorse or promote products derived from this |
| mbed_official | 3:7a284390b0ce | 25 | * software without specific prior written permission. |
| mbed_official | 3:7a284390b0ce | 26 | * |
| mbed_official | 3:7a284390b0ce | 27 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| mbed_official | 3:7a284390b0ce | 28 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| mbed_official | 3:7a284390b0ce | 29 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| mbed_official | 3:7a284390b0ce | 30 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| mbed_official | 3:7a284390b0ce | 31 | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| mbed_official | 3:7a284390b0ce | 32 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| mbed_official | 3:7a284390b0ce | 33 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| mbed_official | 3:7a284390b0ce | 34 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| mbed_official | 3:7a284390b0ce | 35 | * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| mbed_official | 3:7a284390b0ce | 36 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN |
| mbed_official | 3:7a284390b0ce | 37 | * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| mbed_official | 3:7a284390b0ce | 38 | * POSSIBILITY OF SUCH DAMAGE. |
| emilmont | 1:fdd22bb7aa52 | 39 | * ---------------------------------------------------------------------------- */ |
| emilmont | 1:fdd22bb7aa52 | 40 | |
| emilmont | 1:fdd22bb7aa52 | 41 | #include "arm_math.h" |
| emilmont | 1:fdd22bb7aa52 | 42 | |
| emilmont | 1:fdd22bb7aa52 | 43 | /** |
| emilmont | 1:fdd22bb7aa52 | 44 | * @ingroup groupMath |
| emilmont | 1:fdd22bb7aa52 | 45 | */ |
| emilmont | 1:fdd22bb7aa52 | 46 | |
| emilmont | 1:fdd22bb7aa52 | 47 | /** |
| emilmont | 1:fdd22bb7aa52 | 48 | * @defgroup scale Vector Scale |
| emilmont | 1:fdd22bb7aa52 | 49 | * |
| emilmont | 1:fdd22bb7aa52 | 50 | * Multiply a vector by a scalar value. For floating-point data, the algorithm used is: |
| emilmont | 1:fdd22bb7aa52 | 51 | * |
| emilmont | 1:fdd22bb7aa52 | 52 | * <pre> |
| emilmont | 1:fdd22bb7aa52 | 53 | * pDst[n] = pSrc[n] * scale, 0 <= n < blockSize. |
| emilmont | 1:fdd22bb7aa52 | 54 | * </pre> |
| emilmont | 1:fdd22bb7aa52 | 55 | * |
| emilmont | 1:fdd22bb7aa52 | 56 | * In the fixed-point Q7, Q15, and Q31 functions, <code>scale</code> is represented by |
| emilmont | 1:fdd22bb7aa52 | 57 | * a fractional multiplication <code>scaleFract</code> and an arithmetic shift <code>shift</code>. |
| emilmont | 1:fdd22bb7aa52 | 58 | * The shift allows the gain of the scaling operation to exceed 1.0. |
| emilmont | 1:fdd22bb7aa52 | 59 | * The algorithm used with fixed-point data is: |
| emilmont | 1:fdd22bb7aa52 | 60 | * |
| emilmont | 1:fdd22bb7aa52 | 61 | * <pre> |
| emilmont | 1:fdd22bb7aa52 | 62 | * pDst[n] = (pSrc[n] * scaleFract) << shift, 0 <= n < blockSize. |
| emilmont | 1:fdd22bb7aa52 | 63 | * </pre> |
| emilmont | 1:fdd22bb7aa52 | 64 | * |
| emilmont | 1:fdd22bb7aa52 | 65 | * The overall scale factor applied to the fixed-point data is |
| emilmont | 1:fdd22bb7aa52 | 66 | * <pre> |
| emilmont | 1:fdd22bb7aa52 | 67 | * scale = scaleFract * 2^shift. |
| emilmont | 1:fdd22bb7aa52 | 68 | * </pre> |
| mbed_official | 3:7a284390b0ce | 69 | * |
| mbed_official | 3:7a284390b0ce | 70 | * The functions support in-place computation allowing the source and destination |
| mbed_official | 3:7a284390b0ce | 71 | * pointers to reference the same memory buffer. |
| emilmont | 1:fdd22bb7aa52 | 72 | */ |
| emilmont | 1:fdd22bb7aa52 | 73 | |
| emilmont | 1:fdd22bb7aa52 | 74 | /** |
| emilmont | 1:fdd22bb7aa52 | 75 | * @addtogroup scale |
| emilmont | 1:fdd22bb7aa52 | 76 | * @{ |
| emilmont | 1:fdd22bb7aa52 | 77 | */ |
| emilmont | 1:fdd22bb7aa52 | 78 | |
| emilmont | 1:fdd22bb7aa52 | 79 | /** |
| emilmont | 1:fdd22bb7aa52 | 80 | * @brief Multiplies a floating-point vector by a scalar. |
| emilmont | 1:fdd22bb7aa52 | 81 | * @param[in] *pSrc points to the input vector |
| emilmont | 1:fdd22bb7aa52 | 82 | * @param[in] scale scale factor to be applied |
| emilmont | 1:fdd22bb7aa52 | 83 | * @param[out] *pDst points to the output vector |
| emilmont | 1:fdd22bb7aa52 | 84 | * @param[in] blockSize number of samples in the vector |
| emilmont | 1:fdd22bb7aa52 | 85 | * @return none. |
| emilmont | 1:fdd22bb7aa52 | 86 | */ |
| emilmont | 1:fdd22bb7aa52 | 87 | |
| emilmont | 1:fdd22bb7aa52 | 88 | |
| emilmont | 1:fdd22bb7aa52 | 89 | void arm_scale_f32( |
| emilmont | 1:fdd22bb7aa52 | 90 | float32_t * pSrc, |
| emilmont | 1:fdd22bb7aa52 | 91 | float32_t scale, |
| emilmont | 1:fdd22bb7aa52 | 92 | float32_t * pDst, |
| emilmont | 1:fdd22bb7aa52 | 93 | uint32_t blockSize) |
| emilmont | 1:fdd22bb7aa52 | 94 | { |
| emilmont | 1:fdd22bb7aa52 | 95 | uint32_t blkCnt; /* loop counter */ |
| mbed_official | 3:7a284390b0ce | 96 | #ifndef ARM_MATH_CM0_FAMILY |
| emilmont | 1:fdd22bb7aa52 | 97 | |
| emilmont | 1:fdd22bb7aa52 | 98 | /* Run the below code for Cortex-M4 and Cortex-M3 */ |
| emilmont | 1:fdd22bb7aa52 | 99 | float32_t in1, in2, in3, in4; /* temporary variabels */ |
| emilmont | 1:fdd22bb7aa52 | 100 | |
| emilmont | 1:fdd22bb7aa52 | 101 | /*loop Unrolling */ |
| emilmont | 1:fdd22bb7aa52 | 102 | blkCnt = blockSize >> 2u; |
| emilmont | 1:fdd22bb7aa52 | 103 | |
| emilmont | 1:fdd22bb7aa52 | 104 | /* First part of the processing with loop unrolling. Compute 4 outputs at a time. |
| emilmont | 1:fdd22bb7aa52 | 105 | ** a second loop below computes the remaining 1 to 3 samples. */ |
| emilmont | 1:fdd22bb7aa52 | 106 | while(blkCnt > 0u) |
| emilmont | 1:fdd22bb7aa52 | 107 | { |
| emilmont | 1:fdd22bb7aa52 | 108 | /* C = A * scale */ |
| emilmont | 1:fdd22bb7aa52 | 109 | /* Scale the input and then store the results in the destination buffer. */ |
| emilmont | 1:fdd22bb7aa52 | 110 | /* read input samples from source */ |
| emilmont | 1:fdd22bb7aa52 | 111 | in1 = *pSrc; |
| emilmont | 1:fdd22bb7aa52 | 112 | in2 = *(pSrc + 1); |
| emilmont | 1:fdd22bb7aa52 | 113 | |
| emilmont | 1:fdd22bb7aa52 | 114 | /* multiply with scaling factor */ |
| emilmont | 1:fdd22bb7aa52 | 115 | in1 = in1 * scale; |
| emilmont | 1:fdd22bb7aa52 | 116 | |
| emilmont | 1:fdd22bb7aa52 | 117 | /* read input sample from source */ |
| emilmont | 1:fdd22bb7aa52 | 118 | in3 = *(pSrc + 2); |
| emilmont | 1:fdd22bb7aa52 | 119 | |
| emilmont | 1:fdd22bb7aa52 | 120 | /* multiply with scaling factor */ |
| emilmont | 1:fdd22bb7aa52 | 121 | in2 = in2 * scale; |
| emilmont | 1:fdd22bb7aa52 | 122 | |
| emilmont | 1:fdd22bb7aa52 | 123 | /* read input sample from source */ |
| emilmont | 1:fdd22bb7aa52 | 124 | in4 = *(pSrc + 3); |
| emilmont | 1:fdd22bb7aa52 | 125 | |
| emilmont | 1:fdd22bb7aa52 | 126 | /* multiply with scaling factor */ |
| emilmont | 1:fdd22bb7aa52 | 127 | in3 = in3 * scale; |
| emilmont | 1:fdd22bb7aa52 | 128 | in4 = in4 * scale; |
| emilmont | 1:fdd22bb7aa52 | 129 | /* store the result to destination */ |
| emilmont | 1:fdd22bb7aa52 | 130 | *pDst = in1; |
| emilmont | 1:fdd22bb7aa52 | 131 | *(pDst + 1) = in2; |
| emilmont | 1:fdd22bb7aa52 | 132 | *(pDst + 2) = in3; |
| emilmont | 1:fdd22bb7aa52 | 133 | *(pDst + 3) = in4; |
| emilmont | 1:fdd22bb7aa52 | 134 | |
| emilmont | 1:fdd22bb7aa52 | 135 | /* update pointers to process next samples */ |
| emilmont | 1:fdd22bb7aa52 | 136 | pSrc += 4u; |
| emilmont | 1:fdd22bb7aa52 | 137 | pDst += 4u; |
| emilmont | 1:fdd22bb7aa52 | 138 | |
| emilmont | 1:fdd22bb7aa52 | 139 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 140 | blkCnt--; |
| emilmont | 1:fdd22bb7aa52 | 141 | } |
| emilmont | 1:fdd22bb7aa52 | 142 | |
| emilmont | 1:fdd22bb7aa52 | 143 | /* If the blockSize is not a multiple of 4, compute any remaining output samples here. |
| emilmont | 1:fdd22bb7aa52 | 144 | ** No loop unrolling is used. */ |
| emilmont | 1:fdd22bb7aa52 | 145 | blkCnt = blockSize % 0x4u; |
| emilmont | 1:fdd22bb7aa52 | 146 | |
| emilmont | 1:fdd22bb7aa52 | 147 | #else |
| emilmont | 1:fdd22bb7aa52 | 148 | |
| emilmont | 1:fdd22bb7aa52 | 149 | /* Run the below code for Cortex-M0 */ |
| emilmont | 1:fdd22bb7aa52 | 150 | |
| emilmont | 1:fdd22bb7aa52 | 151 | /* Initialize blkCnt with number of samples */ |
| emilmont | 1:fdd22bb7aa52 | 152 | blkCnt = blockSize; |
| emilmont | 1:fdd22bb7aa52 | 153 | |
| mbed_official | 3:7a284390b0ce | 154 | #endif /* #ifndef ARM_MATH_CM0_FAMILY */ |
| emilmont | 1:fdd22bb7aa52 | 155 | |
| emilmont | 1:fdd22bb7aa52 | 156 | while(blkCnt > 0u) |
| emilmont | 1:fdd22bb7aa52 | 157 | { |
| emilmont | 1:fdd22bb7aa52 | 158 | /* C = A * scale */ |
| emilmont | 1:fdd22bb7aa52 | 159 | /* Scale the input and then store the result in the destination buffer. */ |
| emilmont | 1:fdd22bb7aa52 | 160 | *pDst++ = (*pSrc++) * scale; |
| emilmont | 1:fdd22bb7aa52 | 161 | |
| emilmont | 1:fdd22bb7aa52 | 162 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 163 | blkCnt--; |
| emilmont | 1:fdd22bb7aa52 | 164 | } |
| emilmont | 1:fdd22bb7aa52 | 165 | } |
| emilmont | 1:fdd22bb7aa52 | 166 | |
| emilmont | 1:fdd22bb7aa52 | 167 | /** |
| emilmont | 1:fdd22bb7aa52 | 168 | * @} end of scale group |
| emilmont | 1:fdd22bb7aa52 | 169 | */ |