Laxmi Kant Tiwari / mbed-dsp

CMSIS DSP Lib

Fork of mbed-dsp by mbed official

cmsis_dsp/BasicMathFunctions/arm_sub_f32.c@4:9cee975aadce, 2014-06-23 (annotated)

Committer:
mbed_official
Date:
Mon Jun 23 09:30:09 2014 +0100
Revision:
4:9cee975aadce
Parent:
3:7a284390b0ce 
Synchronized with git revision 6e7c7bcec41226f536474daae3c13d49e4c0e865



Full URL: https://github.com/mbedmicro/mbed/commit/6e7c7bcec41226f536474daae3c13d49e4c0e865/



Fix signed unsigned compare in dsp library

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
mbed_official 3:7a284390b0ce 2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
mbed_official 3:7a284390b0ce 4 * $Date: 17. January 2013
mbed_official 3:7a284390b0ce 5 * $Revision: V1.4.1
emilmont 1:fdd22bb7aa52 6 *
emilmont 2:da51fb522205 7 * Project: CMSIS DSP Library
emilmont 2:da51fb522205 8 * Title: arm_sub_f32.c
emilmont 1:fdd22bb7aa52 9 *
emilmont 2:da51fb522205 10 * Description: Floating-point vector subtraction.
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 BasicSub Vector Subtraction
emilmont 1:fdd22bb7aa52 49 *
emilmont 1:fdd22bb7aa52 50 * Element-by-element subtraction of two vectors.
emilmont 1:fdd22bb7aa52 51 *
emilmont 1:fdd22bb7aa52 52 * <pre>
emilmont 1:fdd22bb7aa52 53 * pDst[n] = pSrcA[n] - pSrcB[n], 0 <= n < blockSize.
emilmont 1:fdd22bb7aa52 54 * </pre>
emilmont 1:fdd22bb7aa52 55 *
emilmont 1:fdd22bb7aa52 56 * There are separate functions for floating-point, Q7, Q15, and Q31 data types.
emilmont 1:fdd22bb7aa52 57 */
emilmont 1:fdd22bb7aa52 58
emilmont 1:fdd22bb7aa52 59 /**
emilmont 1:fdd22bb7aa52 60 * @addtogroup BasicSub
emilmont 1:fdd22bb7aa52 61 * @{
emilmont 1:fdd22bb7aa52 62 */
emilmont 1:fdd22bb7aa52 63
emilmont 1:fdd22bb7aa52 64
emilmont 1:fdd22bb7aa52 65 /**
emilmont 1:fdd22bb7aa52 66 * @brief Floating-point vector subtraction.
emilmont 1:fdd22bb7aa52 67 * @param[in] *pSrcA points to the first input vector
emilmont 1:fdd22bb7aa52 68 * @param[in] *pSrcB points to the second input vector
emilmont 1:fdd22bb7aa52 69 * @param[out] *pDst points to the output vector
emilmont 1:fdd22bb7aa52 70 * @param[in] blockSize number of samples in each vector
emilmont 1:fdd22bb7aa52 71 * @return none.
emilmont 1:fdd22bb7aa52 72 */
emilmont 1:fdd22bb7aa52 73
emilmont 1:fdd22bb7aa52 74 void arm_sub_f32(
emilmont 1:fdd22bb7aa52 75 float32_t * pSrcA,
emilmont 1:fdd22bb7aa52 76 float32_t * pSrcB,
emilmont 1:fdd22bb7aa52 77 float32_t * pDst,
emilmont 1:fdd22bb7aa52 78 uint32_t blockSize)
emilmont 1:fdd22bb7aa52 79 {
emilmont 1:fdd22bb7aa52 80 uint32_t blkCnt; /* loop counter */
emilmont 1:fdd22bb7aa52 81
mbed_official 3:7a284390b0ce 82 #ifndef ARM_MATH_CM0_FAMILY
emilmont 1:fdd22bb7aa52 83
emilmont 1:fdd22bb7aa52 84 /* Run the below code for Cortex-M4 and Cortex-M3 */
emilmont 1:fdd22bb7aa52 85 float32_t inA1, inA2, inA3, inA4; /* temporary variables */
emilmont 1:fdd22bb7aa52 86 float32_t inB1, inB2, inB3, inB4; /* temporary variables */
emilmont 1:fdd22bb7aa52 87
emilmont 1:fdd22bb7aa52 88 /*loop Unrolling */
emilmont 1:fdd22bb7aa52 89 blkCnt = blockSize >> 2u;
emilmont 1:fdd22bb7aa52 90
emilmont 1:fdd22bb7aa52 91 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
emilmont 1:fdd22bb7aa52 92 ** a second loop below computes the remaining 1 to 3 samples. */
emilmont 1:fdd22bb7aa52 93 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 94 {
emilmont 1:fdd22bb7aa52 95 /* C = A - B */
emilmont 1:fdd22bb7aa52 96 /* Subtract and then store the results in the destination buffer. */
emilmont 1:fdd22bb7aa52 97 /* Read 4 input samples from sourceA and sourceB */
emilmont 1:fdd22bb7aa52 98 inA1 = *pSrcA;
emilmont 1:fdd22bb7aa52 99 inB1 = *pSrcB;
emilmont 1:fdd22bb7aa52 100 inA2 = *(pSrcA + 1);
emilmont 1:fdd22bb7aa52 101 inB2 = *(pSrcB + 1);
emilmont 1:fdd22bb7aa52 102 inA3 = *(pSrcA + 2);
emilmont 1:fdd22bb7aa52 103 inB3 = *(pSrcB + 2);
emilmont 1:fdd22bb7aa52 104 inA4 = *(pSrcA + 3);
emilmont 1:fdd22bb7aa52 105 inB4 = *(pSrcB + 3);
emilmont 1:fdd22bb7aa52 106
emilmont 1:fdd22bb7aa52 107 /* dst = srcA - srcB */
emilmont 1:fdd22bb7aa52 108 /* subtract and store the result */
emilmont 1:fdd22bb7aa52 109 *pDst = inA1 - inB1;
emilmont 1:fdd22bb7aa52 110 *(pDst + 1) = inA2 - inB2;
emilmont 1:fdd22bb7aa52 111 *(pDst + 2) = inA3 - inB3;
emilmont 1:fdd22bb7aa52 112 *(pDst + 3) = inA4 - inB4;
emilmont 1:fdd22bb7aa52 113
emilmont 1:fdd22bb7aa52 114
emilmont 1:fdd22bb7aa52 115 /* Update pointers to process next sampels */
emilmont 1:fdd22bb7aa52 116 pSrcA += 4u;
emilmont 1:fdd22bb7aa52 117 pSrcB += 4u;
emilmont 1:fdd22bb7aa52 118 pDst += 4u;
emilmont 1:fdd22bb7aa52 119
emilmont 1:fdd22bb7aa52 120 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 121 blkCnt--;
emilmont 1:fdd22bb7aa52 122 }
emilmont 1:fdd22bb7aa52 123
emilmont 1:fdd22bb7aa52 124 /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
emilmont 1:fdd22bb7aa52 125 ** No loop unrolling is used. */
emilmont 1:fdd22bb7aa52 126 blkCnt = blockSize % 0x4u;
emilmont 1:fdd22bb7aa52 127
emilmont 1:fdd22bb7aa52 128 #else
emilmont 1:fdd22bb7aa52 129
emilmont 1:fdd22bb7aa52 130 /* Run the below code for Cortex-M0 */
emilmont 1:fdd22bb7aa52 131
emilmont 1:fdd22bb7aa52 132 /* Initialize blkCnt with number of samples */
emilmont 1:fdd22bb7aa52 133 blkCnt = blockSize;
emilmont 1:fdd22bb7aa52 134
mbed_official 3:7a284390b0ce 135 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
emilmont 1:fdd22bb7aa52 136
emilmont 1:fdd22bb7aa52 137 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 138 {
emilmont 1:fdd22bb7aa52 139 /* C = A - B */
emilmont 1:fdd22bb7aa52 140 /* Subtract and then store the results in the destination buffer. */
emilmont 1:fdd22bb7aa52 141 *pDst++ = (*pSrcA++) - (*pSrcB++);
emilmont 1:fdd22bb7aa52 142
emilmont 1:fdd22bb7aa52 143 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 144 blkCnt--;
emilmont 1:fdd22bb7aa52 145 }
emilmont 1:fdd22bb7aa52 146 }
emilmont 1:fdd22bb7aa52 147
emilmont 1:fdd22bb7aa52 148 /**
emilmont 1:fdd22bb7aa52 149 * @} end of BasicSub group
emilmont 1:fdd22bb7aa52 150 */