Analog Devices / Mbed OS EVAL-CN0540-ARDZ

Dependencies:   platform_drivers LTC26X6 AD77681

CMSIS-DSP_Lib/Source/BasicMathFunctions/arm_scale_f32.c@1:9dd7c64b4a64, 2021-12-06 (annotated)

Committer:
jngarlitos
Date:
Mon Dec 06 05:22:28 2021 +0000
Revision:
1:9dd7c64b4a64
EVAL-CN0540-ARDZ mbed example program Initial Commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
jngarlitos 1:9dd7c64b4a64 1 /* ----------------------------------------------------------------------
jngarlitos 1:9dd7c64b4a64 2 * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
jngarlitos 1:9dd7c64b4a64 3 *
jngarlitos 1:9dd7c64b4a64 4 * $Date: 19. March 2015
jngarlitos 1:9dd7c64b4a64 5 * $Revision: V.1.4.5
jngarlitos 1:9dd7c64b4a64 6 *
jngarlitos 1:9dd7c64b4a64 7 * Project: CMSIS DSP Library
jngarlitos 1:9dd7c64b4a64 8 * Title: arm_scale_f32.c
jngarlitos 1:9dd7c64b4a64 9 *
jngarlitos 1:9dd7c64b4a64 10 * Description: Multiplies a floating-point vector by a scalar.
jngarlitos 1:9dd7c64b4a64 11 *
jngarlitos 1:9dd7c64b4a64 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
jngarlitos 1:9dd7c64b4a64 13 *
jngarlitos 1:9dd7c64b4a64 14 * Redistribution and use in source and binary forms, with or without
jngarlitos 1:9dd7c64b4a64 15 * modification, are permitted provided that the following conditions
jngarlitos 1:9dd7c64b4a64 16 * are met:
jngarlitos 1:9dd7c64b4a64 17 * - Redistributions of source code must retain the above copyright
jngarlitos 1:9dd7c64b4a64 18 * notice, this list of conditions and the following disclaimer.
jngarlitos 1:9dd7c64b4a64 19 * - Redistributions in binary form must reproduce the above copyright
jngarlitos 1:9dd7c64b4a64 20 * notice, this list of conditions and the following disclaimer in
jngarlitos 1:9dd7c64b4a64 21 * the documentation and/or other materials provided with the
jngarlitos 1:9dd7c64b4a64 22 * distribution.
jngarlitos 1:9dd7c64b4a64 23 * - Neither the name of ARM LIMITED nor the names of its contributors
jngarlitos 1:9dd7c64b4a64 24 * may be used to endorse or promote products derived from this
jngarlitos 1:9dd7c64b4a64 25 * software without specific prior written permission.
jngarlitos 1:9dd7c64b4a64 26 *
jngarlitos 1:9dd7c64b4a64 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
jngarlitos 1:9dd7c64b4a64 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
jngarlitos 1:9dd7c64b4a64 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
jngarlitos 1:9dd7c64b4a64 30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
jngarlitos 1:9dd7c64b4a64 31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
jngarlitos 1:9dd7c64b4a64 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
jngarlitos 1:9dd7c64b4a64 33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
jngarlitos 1:9dd7c64b4a64 34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
jngarlitos 1:9dd7c64b4a64 35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
jngarlitos 1:9dd7c64b4a64 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
jngarlitos 1:9dd7c64b4a64 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
jngarlitos 1:9dd7c64b4a64 38 * POSSIBILITY OF SUCH DAMAGE.
jngarlitos 1:9dd7c64b4a64 39 * ---------------------------------------------------------------------------- */
jngarlitos 1:9dd7c64b4a64 40
jngarlitos 1:9dd7c64b4a64 41 #include "arm_math.h"
jngarlitos 1:9dd7c64b4a64 42
jngarlitos 1:9dd7c64b4a64 43 /**
jngarlitos 1:9dd7c64b4a64 44 * @ingroup groupMath
jngarlitos 1:9dd7c64b4a64 45 */
jngarlitos 1:9dd7c64b4a64 46
jngarlitos 1:9dd7c64b4a64 47 /**
jngarlitos 1:9dd7c64b4a64 48 * @defgroup scale Vector Scale
jngarlitos 1:9dd7c64b4a64 49 *
jngarlitos 1:9dd7c64b4a64 50 * Multiply a vector by a scalar value. For floating-point data, the algorithm used is:
jngarlitos 1:9dd7c64b4a64 51 *
jngarlitos 1:9dd7c64b4a64 52 * <pre>
jngarlitos 1:9dd7c64b4a64 53 * pDst[n] = pSrc[n] * scale, 0 <= n < blockSize.
jngarlitos 1:9dd7c64b4a64 54 * </pre>
jngarlitos 1:9dd7c64b4a64 55 *
jngarlitos 1:9dd7c64b4a64 56 * In the fixed-point Q7, Q15, and Q31 functions, <code>scale</code> is represented by
jngarlitos 1:9dd7c64b4a64 57 * a fractional multiplication <code>scaleFract</code> and an arithmetic shift <code>shift</code>.
jngarlitos 1:9dd7c64b4a64 58 * The shift allows the gain of the scaling operation to exceed 1.0.
jngarlitos 1:9dd7c64b4a64 59 * The algorithm used with fixed-point data is:
jngarlitos 1:9dd7c64b4a64 60 *
jngarlitos 1:9dd7c64b4a64 61 * <pre>
jngarlitos 1:9dd7c64b4a64 62 * pDst[n] = (pSrc[n] * scaleFract) << shift, 0 <= n < blockSize.
jngarlitos 1:9dd7c64b4a64 63 * </pre>
jngarlitos 1:9dd7c64b4a64 64 *
jngarlitos 1:9dd7c64b4a64 65 * The overall scale factor applied to the fixed-point data is
jngarlitos 1:9dd7c64b4a64 66 * <pre>
jngarlitos 1:9dd7c64b4a64 67 * scale = scaleFract * 2^shift.
jngarlitos 1:9dd7c64b4a64 68 * </pre>
jngarlitos 1:9dd7c64b4a64 69 *
jngarlitos 1:9dd7c64b4a64 70 * The functions support in-place computation allowing the source and destination
jngarlitos 1:9dd7c64b4a64 71 * pointers to reference the same memory buffer.
jngarlitos 1:9dd7c64b4a64 72 */
jngarlitos 1:9dd7c64b4a64 73
jngarlitos 1:9dd7c64b4a64 74 /**
jngarlitos 1:9dd7c64b4a64 75 * @addtogroup scale
jngarlitos 1:9dd7c64b4a64 76 * @{
jngarlitos 1:9dd7c64b4a64 77 */
jngarlitos 1:9dd7c64b4a64 78
jngarlitos 1:9dd7c64b4a64 79 /**
jngarlitos 1:9dd7c64b4a64 80 * @brief Multiplies a floating-point vector by a scalar.
jngarlitos 1:9dd7c64b4a64 81 * @param[in] *pSrc points to the input vector
jngarlitos 1:9dd7c64b4a64 82 * @param[in] scale scale factor to be applied
jngarlitos 1:9dd7c64b4a64 83 * @param[out] *pDst points to the output vector
jngarlitos 1:9dd7c64b4a64 84 * @param[in] blockSize number of samples in the vector
jngarlitos 1:9dd7c64b4a64 85 * @return none.
jngarlitos 1:9dd7c64b4a64 86 */
jngarlitos 1:9dd7c64b4a64 87
jngarlitos 1:9dd7c64b4a64 88
jngarlitos 1:9dd7c64b4a64 89 void arm_scale_f32(
jngarlitos 1:9dd7c64b4a64 90 float32_t * pSrc,
jngarlitos 1:9dd7c64b4a64 91 float32_t scale,
jngarlitos 1:9dd7c64b4a64 92 float32_t * pDst,
jngarlitos 1:9dd7c64b4a64 93 uint32_t blockSize)
jngarlitos 1:9dd7c64b4a64 94 {
jngarlitos 1:9dd7c64b4a64 95 uint32_t blkCnt; /* loop counter */
jngarlitos 1:9dd7c64b4a64 96 #ifndef ARM_MATH_CM0_FAMILY
jngarlitos 1:9dd7c64b4a64 97
jngarlitos 1:9dd7c64b4a64 98 /* Run the below code for Cortex-M4 and Cortex-M3 */
jngarlitos 1:9dd7c64b4a64 99 float32_t in1, in2, in3, in4; /* temporary variabels */
jngarlitos 1:9dd7c64b4a64 100
jngarlitos 1:9dd7c64b4a64 101 /*loop Unrolling */
jngarlitos 1:9dd7c64b4a64 102 blkCnt = blockSize >> 2u;
jngarlitos 1:9dd7c64b4a64 103
jngarlitos 1:9dd7c64b4a64 104 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
jngarlitos 1:9dd7c64b4a64 105 ** a second loop below computes the remaining 1 to 3 samples. */
jngarlitos 1:9dd7c64b4a64 106 while(blkCnt > 0u)
jngarlitos 1:9dd7c64b4a64 107 {
jngarlitos 1:9dd7c64b4a64 108 /* C = A * scale */
jngarlitos 1:9dd7c64b4a64 109 /* Scale the input and then store the results in the destination buffer. */
jngarlitos 1:9dd7c64b4a64 110 /* read input samples from source */
jngarlitos 1:9dd7c64b4a64 111 in1 = *pSrc;
jngarlitos 1:9dd7c64b4a64 112 in2 = *(pSrc + 1);
jngarlitos 1:9dd7c64b4a64 113
jngarlitos 1:9dd7c64b4a64 114 /* multiply with scaling factor */
jngarlitos 1:9dd7c64b4a64 115 in1 = in1 * scale;
jngarlitos 1:9dd7c64b4a64 116
jngarlitos 1:9dd7c64b4a64 117 /* read input sample from source */
jngarlitos 1:9dd7c64b4a64 118 in3 = *(pSrc + 2);
jngarlitos 1:9dd7c64b4a64 119
jngarlitos 1:9dd7c64b4a64 120 /* multiply with scaling factor */
jngarlitos 1:9dd7c64b4a64 121 in2 = in2 * scale;
jngarlitos 1:9dd7c64b4a64 122
jngarlitos 1:9dd7c64b4a64 123 /* read input sample from source */
jngarlitos 1:9dd7c64b4a64 124 in4 = *(pSrc + 3);
jngarlitos 1:9dd7c64b4a64 125
jngarlitos 1:9dd7c64b4a64 126 /* multiply with scaling factor */
jngarlitos 1:9dd7c64b4a64 127 in3 = in3 * scale;
jngarlitos 1:9dd7c64b4a64 128 in4 = in4 * scale;
jngarlitos 1:9dd7c64b4a64 129 /* store the result to destination */
jngarlitos 1:9dd7c64b4a64 130 *pDst = in1;
jngarlitos 1:9dd7c64b4a64 131 *(pDst + 1) = in2;
jngarlitos 1:9dd7c64b4a64 132 *(pDst + 2) = in3;
jngarlitos 1:9dd7c64b4a64 133 *(pDst + 3) = in4;
jngarlitos 1:9dd7c64b4a64 134
jngarlitos 1:9dd7c64b4a64 135 /* update pointers to process next samples */
jngarlitos 1:9dd7c64b4a64 136 pSrc += 4u;
jngarlitos 1:9dd7c64b4a64 137 pDst += 4u;
jngarlitos 1:9dd7c64b4a64 138
jngarlitos 1:9dd7c64b4a64 139 /* Decrement the loop counter */
jngarlitos 1:9dd7c64b4a64 140 blkCnt--;
jngarlitos 1:9dd7c64b4a64 141 }
jngarlitos 1:9dd7c64b4a64 142
jngarlitos 1:9dd7c64b4a64 143 /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
jngarlitos 1:9dd7c64b4a64 144 ** No loop unrolling is used. */
jngarlitos 1:9dd7c64b4a64 145 blkCnt = blockSize % 0x4u;
jngarlitos 1:9dd7c64b4a64 146
jngarlitos 1:9dd7c64b4a64 147 #else
jngarlitos 1:9dd7c64b4a64 148
jngarlitos 1:9dd7c64b4a64 149 /* Run the below code for Cortex-M0 */
jngarlitos 1:9dd7c64b4a64 150
jngarlitos 1:9dd7c64b4a64 151 /* Initialize blkCnt with number of samples */
jngarlitos 1:9dd7c64b4a64 152 blkCnt = blockSize;
jngarlitos 1:9dd7c64b4a64 153
jngarlitos 1:9dd7c64b4a64 154 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
jngarlitos 1:9dd7c64b4a64 155
jngarlitos 1:9dd7c64b4a64 156 while(blkCnt > 0u)
jngarlitos 1:9dd7c64b4a64 157 {
jngarlitos 1:9dd7c64b4a64 158 /* C = A * scale */
jngarlitos 1:9dd7c64b4a64 159 /* Scale the input and then store the result in the destination buffer. */
jngarlitos 1:9dd7c64b4a64 160 *pDst++ = (*pSrc++) * scale;
jngarlitos 1:9dd7c64b4a64 161
jngarlitos 1:9dd7c64b4a64 162 /* Decrement the loop counter */
jngarlitos 1:9dd7c64b4a64 163 blkCnt--;
jngarlitos 1:9dd7c64b4a64 164 }
jngarlitos 1:9dd7c64b4a64 165 }
jngarlitos 1:9dd7c64b4a64 166
jngarlitos 1:9dd7c64b4a64 167 /**
jngarlitos 1:9dd7c64b4a64 168 * @} end of scale group
jngarlitos 1:9dd7c64b4a64 169 */