Eli Hughes / CMSIS_DSP_401

V4.0.1 of the ARM CMSIS DSP libraries. Note that arm_bitreversal2.s, arm_cfft_f32.c and arm_rfft_fast_f32.c had to be removed. arm_bitreversal2.s will not assemble with the online tools. So, the fast f32 FFT functions are not yet available. All the other FFT functions are available.

Dependents:   MPU9150_Example fir_f32 fir_f32 MPU9150_nucleo_noni2cdev ... more

FilteringFunctions/arm_correlate_fast_q31.c@0:3d9c67d97d6f, 2014-07-28 (annotated)

Committer:
emh203
Date:
Mon Jul 28 15:03:15 2014 +0000
Revision:
0:3d9c67d97d6f
1st working commit.   Had to remove arm_bitreversal2.s     arm_cfft_f32.c and arm_rfft_fast_f32.c.    The .s will not assemble.      For now I removed these functions so we could at least have a library for the other functions.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emh203 0:3d9c67d97d6f 1 /* ----------------------------------------------------------------------
emh203 0:3d9c67d97d6f 2 * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
emh203 0:3d9c67d97d6f 3 *
emh203 0:3d9c67d97d6f 4 * $Date: 12. March 2014
emh203 0:3d9c67d97d6f 5 * $Revision: V1.4.3
emh203 0:3d9c67d97d6f 6 *
emh203 0:3d9c67d97d6f 7 * Project: CMSIS DSP Library
emh203 0:3d9c67d97d6f 8 * Title: arm_correlate_fast_q31.c
emh203 0:3d9c67d97d6f 9 *
emh203 0:3d9c67d97d6f 10 * Description: Fast Q31 Correlation.
emh203 0:3d9c67d97d6f 11 *
emh203 0:3d9c67d97d6f 12 * Target Processor: Cortex-M4/Cortex-M3
emh203 0:3d9c67d97d6f 13 *
emh203 0:3d9c67d97d6f 14 * Redistribution and use in source and binary forms, with or without
emh203 0:3d9c67d97d6f 15 * modification, are permitted provided that the following conditions
emh203 0:3d9c67d97d6f 16 * are met:
emh203 0:3d9c67d97d6f 17 * - Redistributions of source code must retain the above copyright
emh203 0:3d9c67d97d6f 18 * notice, this list of conditions and the following disclaimer.
emh203 0:3d9c67d97d6f 19 * - Redistributions in binary form must reproduce the above copyright
emh203 0:3d9c67d97d6f 20 * notice, this list of conditions and the following disclaimer in
emh203 0:3d9c67d97d6f 21 * the documentation and/or other materials provided with the
emh203 0:3d9c67d97d6f 22 * distribution.
emh203 0:3d9c67d97d6f 23 * - Neither the name of ARM LIMITED nor the names of its contributors
emh203 0:3d9c67d97d6f 24 * may be used to endorse or promote products derived from this
emh203 0:3d9c67d97d6f 25 * software without specific prior written permission.
emh203 0:3d9c67d97d6f 26 *
emh203 0:3d9c67d97d6f 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
emh203 0:3d9c67d97d6f 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
emh203 0:3d9c67d97d6f 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
emh203 0:3d9c67d97d6f 30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
emh203 0:3d9c67d97d6f 31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
emh203 0:3d9c67d97d6f 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
emh203 0:3d9c67d97d6f 33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
emh203 0:3d9c67d97d6f 34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
emh203 0:3d9c67d97d6f 35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
emh203 0:3d9c67d97d6f 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
emh203 0:3d9c67d97d6f 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
emh203 0:3d9c67d97d6f 38 * POSSIBILITY OF SUCH DAMAGE.
emh203 0:3d9c67d97d6f 39 * -------------------------------------------------------------------- */
emh203 0:3d9c67d97d6f 40
emh203 0:3d9c67d97d6f 41 #include "arm_math.h"
emh203 0:3d9c67d97d6f 42
emh203 0:3d9c67d97d6f 43 /**
emh203 0:3d9c67d97d6f 44 * @ingroup groupFilters
emh203 0:3d9c67d97d6f 45 */
emh203 0:3d9c67d97d6f 46
emh203 0:3d9c67d97d6f 47 /**
emh203 0:3d9c67d97d6f 48 * @addtogroup Corr
emh203 0:3d9c67d97d6f 49 * @{
emh203 0:3d9c67d97d6f 50 */
emh203 0:3d9c67d97d6f 51
emh203 0:3d9c67d97d6f 52 /**
emh203 0:3d9c67d97d6f 53 * @brief Correlation of Q31 sequences (fast version) for Cortex-M3 and Cortex-M4.
emh203 0:3d9c67d97d6f 54 * @param[in] *pSrcA points to the first input sequence.
emh203 0:3d9c67d97d6f 55 * @param[in] srcALen length of the first input sequence.
emh203 0:3d9c67d97d6f 56 * @param[in] *pSrcB points to the second input sequence.
emh203 0:3d9c67d97d6f 57 * @param[in] srcBLen length of the second input sequence.
emh203 0:3d9c67d97d6f 58 * @param[out] *pDst points to the location where the output result is written. Length 2 * max(srcALen, srcBLen) - 1.
emh203 0:3d9c67d97d6f 59 * @return none.
emh203 0:3d9c67d97d6f 60 *
emh203 0:3d9c67d97d6f 61 * @details
emh203 0:3d9c67d97d6f 62 * <b>Scaling and Overflow Behavior:</b>
emh203 0:3d9c67d97d6f 63 *
emh203 0:3d9c67d97d6f 64 * \par
emh203 0:3d9c67d97d6f 65 * This function is optimized for speed at the expense of fixed-point precision and overflow protection.
emh203 0:3d9c67d97d6f 66 * The result of each 1.31 x 1.31 multiplication is truncated to 2.30 format.
emh203 0:3d9c67d97d6f 67 * These intermediate results are accumulated in a 32-bit register in 2.30 format.
emh203 0:3d9c67d97d6f 68 * Finally, the accumulator is saturated and converted to a 1.31 result.
emh203 0:3d9c67d97d6f 69 *
emh203 0:3d9c67d97d6f 70 * \par
emh203 0:3d9c67d97d6f 71 * The fast version has the same overflow behavior as the standard version but provides less precision since it discards the low 32 bits of each multiplication result.
emh203 0:3d9c67d97d6f 72 * In order to avoid overflows completely the input signals must be scaled down.
emh203 0:3d9c67d97d6f 73 * The input signals should be scaled down to avoid intermediate overflows.
emh203 0:3d9c67d97d6f 74 * Scale down one of the inputs by 1/min(srcALen, srcBLen)to avoid overflows since a
emh203 0:3d9c67d97d6f 75 * maximum of min(srcALen, srcBLen) number of additions is carried internally.
emh203 0:3d9c67d97d6f 76 *
emh203 0:3d9c67d97d6f 77 * \par
emh203 0:3d9c67d97d6f 78 * See <code>arm_correlate_q31()</code> for a slower implementation of this function which uses 64-bit accumulation to provide higher precision.
emh203 0:3d9c67d97d6f 79 */
emh203 0:3d9c67d97d6f 80
emh203 0:3d9c67d97d6f 81 void arm_correlate_fast_q31(
emh203 0:3d9c67d97d6f 82 q31_t * pSrcA,
emh203 0:3d9c67d97d6f 83 uint32_t srcALen,
emh203 0:3d9c67d97d6f 84 q31_t * pSrcB,
emh203 0:3d9c67d97d6f 85 uint32_t srcBLen,
emh203 0:3d9c67d97d6f 86 q31_t * pDst)
emh203 0:3d9c67d97d6f 87 {
emh203 0:3d9c67d97d6f 88 q31_t *pIn1; /* inputA pointer */
emh203 0:3d9c67d97d6f 89 q31_t *pIn2; /* inputB pointer */
emh203 0:3d9c67d97d6f 90 q31_t *pOut = pDst; /* output pointer */
emh203 0:3d9c67d97d6f 91 q31_t *px; /* Intermediate inputA pointer */
emh203 0:3d9c67d97d6f 92 q31_t *py; /* Intermediate inputB pointer */
emh203 0:3d9c67d97d6f 93 q31_t *pSrc1; /* Intermediate pointers */
emh203 0:3d9c67d97d6f 94 q31_t sum, acc0, acc1, acc2, acc3; /* Accumulators */
emh203 0:3d9c67d97d6f 95 q31_t x0, x1, x2, x3, c0; /* temporary variables for holding input and coefficient values */
emh203 0:3d9c67d97d6f 96 uint32_t j, k = 0u, count, blkCnt, outBlockSize, blockSize1, blockSize2, blockSize3; /* loop counter */
emh203 0:3d9c67d97d6f 97 int32_t inc = 1; /* Destination address modifier */
emh203 0:3d9c67d97d6f 98
emh203 0:3d9c67d97d6f 99
emh203 0:3d9c67d97d6f 100 /* The algorithm implementation is based on the lengths of the inputs. */
emh203 0:3d9c67d97d6f 101 /* srcB is always made to slide across srcA. */
emh203 0:3d9c67d97d6f 102 /* So srcBLen is always considered as shorter or equal to srcALen */
emh203 0:3d9c67d97d6f 103 if(srcALen >= srcBLen)
emh203 0:3d9c67d97d6f 104 {
emh203 0:3d9c67d97d6f 105 /* Initialization of inputA pointer */
emh203 0:3d9c67d97d6f 106 pIn1 = (pSrcA);
emh203 0:3d9c67d97d6f 107
emh203 0:3d9c67d97d6f 108 /* Initialization of inputB pointer */
emh203 0:3d9c67d97d6f 109 pIn2 = (pSrcB);
emh203 0:3d9c67d97d6f 110
emh203 0:3d9c67d97d6f 111 /* Number of output samples is calculated */
emh203 0:3d9c67d97d6f 112 outBlockSize = (2u * srcALen) - 1u;
emh203 0:3d9c67d97d6f 113
emh203 0:3d9c67d97d6f 114 /* When srcALen > srcBLen, zero padding is done to srcB
emh203 0:3d9c67d97d6f 115 * to make their lengths equal.
emh203 0:3d9c67d97d6f 116 * Instead, (outBlockSize - (srcALen + srcBLen - 1))
emh203 0:3d9c67d97d6f 117 * number of output samples are made zero */
emh203 0:3d9c67d97d6f 118 j = outBlockSize - (srcALen + (srcBLen - 1u));
emh203 0:3d9c67d97d6f 119
emh203 0:3d9c67d97d6f 120 /* Updating the pointer position to non zero value */
emh203 0:3d9c67d97d6f 121 pOut += j;
emh203 0:3d9c67d97d6f 122
emh203 0:3d9c67d97d6f 123 }
emh203 0:3d9c67d97d6f 124 else
emh203 0:3d9c67d97d6f 125 {
emh203 0:3d9c67d97d6f 126 /* Initialization of inputA pointer */
emh203 0:3d9c67d97d6f 127 pIn1 = (pSrcB);
emh203 0:3d9c67d97d6f 128
emh203 0:3d9c67d97d6f 129 /* Initialization of inputB pointer */
emh203 0:3d9c67d97d6f 130 pIn2 = (pSrcA);
emh203 0:3d9c67d97d6f 131
emh203 0:3d9c67d97d6f 132 /* srcBLen is always considered as shorter or equal to srcALen */
emh203 0:3d9c67d97d6f 133 j = srcBLen;
emh203 0:3d9c67d97d6f 134 srcBLen = srcALen;
emh203 0:3d9c67d97d6f 135 srcALen = j;
emh203 0:3d9c67d97d6f 136
emh203 0:3d9c67d97d6f 137 /* CORR(x, y) = Reverse order(CORR(y, x)) */
emh203 0:3d9c67d97d6f 138 /* Hence set the destination pointer to point to the last output sample */
emh203 0:3d9c67d97d6f 139 pOut = pDst + ((srcALen + srcBLen) - 2u);
emh203 0:3d9c67d97d6f 140
emh203 0:3d9c67d97d6f 141 /* Destination address modifier is set to -1 */
emh203 0:3d9c67d97d6f 142 inc = -1;
emh203 0:3d9c67d97d6f 143
emh203 0:3d9c67d97d6f 144 }
emh203 0:3d9c67d97d6f 145
emh203 0:3d9c67d97d6f 146 /* The function is internally
emh203 0:3d9c67d97d6f 147 * divided into three parts according to the number of multiplications that has to be
emh203 0:3d9c67d97d6f 148 * taken place between inputA samples and inputB samples. In the first part of the
emh203 0:3d9c67d97d6f 149 * algorithm, the multiplications increase by one for every iteration.
emh203 0:3d9c67d97d6f 150 * In the second part of the algorithm, srcBLen number of multiplications are done.
emh203 0:3d9c67d97d6f 151 * In the third part of the algorithm, the multiplications decrease by one
emh203 0:3d9c67d97d6f 152 * for every iteration.*/
emh203 0:3d9c67d97d6f 153 /* The algorithm is implemented in three stages.
emh203 0:3d9c67d97d6f 154 * The loop counters of each stage is initiated here. */
emh203 0:3d9c67d97d6f 155 blockSize1 = srcBLen - 1u;
emh203 0:3d9c67d97d6f 156 blockSize2 = srcALen - (srcBLen - 1u);
emh203 0:3d9c67d97d6f 157 blockSize3 = blockSize1;
emh203 0:3d9c67d97d6f 158
emh203 0:3d9c67d97d6f 159 /* --------------------------
emh203 0:3d9c67d97d6f 160 * Initializations of stage1
emh203 0:3d9c67d97d6f 161 * -------------------------*/
emh203 0:3d9c67d97d6f 162
emh203 0:3d9c67d97d6f 163 /* sum = x[0] * y[srcBlen - 1]
emh203 0:3d9c67d97d6f 164 * sum = x[0] * y[srcBlen - 2] + x[1] * y[srcBlen - 1]
emh203 0:3d9c67d97d6f 165 * ....
emh203 0:3d9c67d97d6f 166 * sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen - 1] * y[srcBLen - 1]
emh203 0:3d9c67d97d6f 167 */
emh203 0:3d9c67d97d6f 168
emh203 0:3d9c67d97d6f 169 /* In this stage the MAC operations are increased by 1 for every iteration.
emh203 0:3d9c67d97d6f 170 The count variable holds the number of MAC operations performed */
emh203 0:3d9c67d97d6f 171 count = 1u;
emh203 0:3d9c67d97d6f 172
emh203 0:3d9c67d97d6f 173 /* Working pointer of inputA */
emh203 0:3d9c67d97d6f 174 px = pIn1;
emh203 0:3d9c67d97d6f 175
emh203 0:3d9c67d97d6f 176 /* Working pointer of inputB */
emh203 0:3d9c67d97d6f 177 pSrc1 = pIn2 + (srcBLen - 1u);
emh203 0:3d9c67d97d6f 178 py = pSrc1;
emh203 0:3d9c67d97d6f 179
emh203 0:3d9c67d97d6f 180 /* ------------------------
emh203 0:3d9c67d97d6f 181 * Stage1 process
emh203 0:3d9c67d97d6f 182 * ----------------------*/
emh203 0:3d9c67d97d6f 183
emh203 0:3d9c67d97d6f 184 /* The first stage starts here */
emh203 0:3d9c67d97d6f 185 while(blockSize1 > 0u)
emh203 0:3d9c67d97d6f 186 {
emh203 0:3d9c67d97d6f 187 /* Accumulator is made zero for every iteration */
emh203 0:3d9c67d97d6f 188 sum = 0;
emh203 0:3d9c67d97d6f 189
emh203 0:3d9c67d97d6f 190 /* Apply loop unrolling and compute 4 MACs simultaneously. */
emh203 0:3d9c67d97d6f 191 k = count >> 2;
emh203 0:3d9c67d97d6f 192
emh203 0:3d9c67d97d6f 193 /* First part of the processing with loop unrolling. Compute 4 MACs at a time.
emh203 0:3d9c67d97d6f 194 ** a second loop below computes MACs for the remaining 1 to 3 samples. */
emh203 0:3d9c67d97d6f 195 while(k > 0u)
emh203 0:3d9c67d97d6f 196 {
emh203 0:3d9c67d97d6f 197 /* x[0] * y[srcBLen - 4] */
emh203 0:3d9c67d97d6f 198 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 199 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 200 /* x[1] * y[srcBLen - 3] */
emh203 0:3d9c67d97d6f 201 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 202 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 203 /* x[2] * y[srcBLen - 2] */
emh203 0:3d9c67d97d6f 204 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 205 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 206 /* x[3] * y[srcBLen - 1] */
emh203 0:3d9c67d97d6f 207 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 208 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 209
emh203 0:3d9c67d97d6f 210 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 211 k--;
emh203 0:3d9c67d97d6f 212 }
emh203 0:3d9c67d97d6f 213
emh203 0:3d9c67d97d6f 214 /* If the count is not a multiple of 4, compute any remaining MACs here.
emh203 0:3d9c67d97d6f 215 ** No loop unrolling is used. */
emh203 0:3d9c67d97d6f 216 k = count % 0x4u;
emh203 0:3d9c67d97d6f 217
emh203 0:3d9c67d97d6f 218 while(k > 0u)
emh203 0:3d9c67d97d6f 219 {
emh203 0:3d9c67d97d6f 220 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 221 /* x[0] * y[srcBLen - 1] */
emh203 0:3d9c67d97d6f 222 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 223 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 224
emh203 0:3d9c67d97d6f 225 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 226 k--;
emh203 0:3d9c67d97d6f 227 }
emh203 0:3d9c67d97d6f 228
emh203 0:3d9c67d97d6f 229 /* Store the result in the accumulator in the destination buffer. */
emh203 0:3d9c67d97d6f 230 *pOut = sum << 1;
emh203 0:3d9c67d97d6f 231 /* Destination pointer is updated according to the address modifier, inc */
emh203 0:3d9c67d97d6f 232 pOut += inc;
emh203 0:3d9c67d97d6f 233
emh203 0:3d9c67d97d6f 234 /* Update the inputA and inputB pointers for next MAC calculation */
emh203 0:3d9c67d97d6f 235 py = pSrc1 - count;
emh203 0:3d9c67d97d6f 236 px = pIn1;
emh203 0:3d9c67d97d6f 237
emh203 0:3d9c67d97d6f 238 /* Increment the MAC count */
emh203 0:3d9c67d97d6f 239 count++;
emh203 0:3d9c67d97d6f 240
emh203 0:3d9c67d97d6f 241 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 242 blockSize1--;
emh203 0:3d9c67d97d6f 243 }
emh203 0:3d9c67d97d6f 244
emh203 0:3d9c67d97d6f 245 /* --------------------------
emh203 0:3d9c67d97d6f 246 * Initializations of stage2
emh203 0:3d9c67d97d6f 247 * ------------------------*/
emh203 0:3d9c67d97d6f 248
emh203 0:3d9c67d97d6f 249 /* sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen-1] * y[srcBLen-1]
emh203 0:3d9c67d97d6f 250 * sum = x[1] * y[0] + x[2] * y[1] +...+ x[srcBLen] * y[srcBLen-1]
emh203 0:3d9c67d97d6f 251 * ....
emh203 0:3d9c67d97d6f 252 * sum = x[srcALen-srcBLen-2] * y[0] + x[srcALen-srcBLen-1] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
emh203 0:3d9c67d97d6f 253 */
emh203 0:3d9c67d97d6f 254
emh203 0:3d9c67d97d6f 255 /* Working pointer of inputA */
emh203 0:3d9c67d97d6f 256 px = pIn1;
emh203 0:3d9c67d97d6f 257
emh203 0:3d9c67d97d6f 258 /* Working pointer of inputB */
emh203 0:3d9c67d97d6f 259 py = pIn2;
emh203 0:3d9c67d97d6f 260
emh203 0:3d9c67d97d6f 261 /* count is index by which the pointer pIn1 to be incremented */
emh203 0:3d9c67d97d6f 262 count = 0u;
emh203 0:3d9c67d97d6f 263
emh203 0:3d9c67d97d6f 264 /* -------------------
emh203 0:3d9c67d97d6f 265 * Stage2 process
emh203 0:3d9c67d97d6f 266 * ------------------*/
emh203 0:3d9c67d97d6f 267
emh203 0:3d9c67d97d6f 268 /* Stage2 depends on srcBLen as in this stage srcBLen number of MACS are performed.
emh203 0:3d9c67d97d6f 269 * So, to loop unroll over blockSize2,
emh203 0:3d9c67d97d6f 270 * srcBLen should be greater than or equal to 4 */
emh203 0:3d9c67d97d6f 271 if(srcBLen >= 4u)
emh203 0:3d9c67d97d6f 272 {
emh203 0:3d9c67d97d6f 273 /* Loop unroll over blockSize2, by 4 */
emh203 0:3d9c67d97d6f 274 blkCnt = blockSize2 >> 2u;
emh203 0:3d9c67d97d6f 275
emh203 0:3d9c67d97d6f 276 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 277 {
emh203 0:3d9c67d97d6f 278 /* Set all accumulators to zero */
emh203 0:3d9c67d97d6f 279 acc0 = 0;
emh203 0:3d9c67d97d6f 280 acc1 = 0;
emh203 0:3d9c67d97d6f 281 acc2 = 0;
emh203 0:3d9c67d97d6f 282 acc3 = 0;
emh203 0:3d9c67d97d6f 283
emh203 0:3d9c67d97d6f 284 /* read x[0], x[1], x[2] samples */
emh203 0:3d9c67d97d6f 285 x0 = *(px++);
emh203 0:3d9c67d97d6f 286 x1 = *(px++);
emh203 0:3d9c67d97d6f 287 x2 = *(px++);
emh203 0:3d9c67d97d6f 288
emh203 0:3d9c67d97d6f 289 /* Apply loop unrolling and compute 4 MACs simultaneously. */
emh203 0:3d9c67d97d6f 290 k = srcBLen >> 2u;
emh203 0:3d9c67d97d6f 291
emh203 0:3d9c67d97d6f 292 /* First part of the processing with loop unrolling. Compute 4 MACs at a time.
emh203 0:3d9c67d97d6f 293 ** a second loop below computes MACs for the remaining 1 to 3 samples. */
emh203 0:3d9c67d97d6f 294 do
emh203 0:3d9c67d97d6f 295 {
emh203 0:3d9c67d97d6f 296 /* Read y[0] sample */
emh203 0:3d9c67d97d6f 297 c0 = *(py++);
emh203 0:3d9c67d97d6f 298
emh203 0:3d9c67d97d6f 299 /* Read x[3] sample */
emh203 0:3d9c67d97d6f 300 x3 = *(px++);
emh203 0:3d9c67d97d6f 301
emh203 0:3d9c67d97d6f 302 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 303 /* acc0 += x[0] * y[0] */
emh203 0:3d9c67d97d6f 304 acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
emh203 0:3d9c67d97d6f 305 /* acc1 += x[1] * y[0] */
emh203 0:3d9c67d97d6f 306 acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
emh203 0:3d9c67d97d6f 307 /* acc2 += x[2] * y[0] */
emh203 0:3d9c67d97d6f 308 acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x2 * c0)) >> 32);
emh203 0:3d9c67d97d6f 309 /* acc3 += x[3] * y[0] */
emh203 0:3d9c67d97d6f 310 acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x3 * c0)) >> 32);
emh203 0:3d9c67d97d6f 311
emh203 0:3d9c67d97d6f 312 /* Read y[1] sample */
emh203 0:3d9c67d97d6f 313 c0 = *(py++);
emh203 0:3d9c67d97d6f 314
emh203 0:3d9c67d97d6f 315 /* Read x[4] sample */
emh203 0:3d9c67d97d6f 316 x0 = *(px++);
emh203 0:3d9c67d97d6f 317
emh203 0:3d9c67d97d6f 318 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 319 /* acc0 += x[1] * y[1] */
emh203 0:3d9c67d97d6f 320 acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x1 * c0)) >> 32);
emh203 0:3d9c67d97d6f 321 /* acc1 += x[2] * y[1] */
emh203 0:3d9c67d97d6f 322 acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x2 * c0)) >> 32);
emh203 0:3d9c67d97d6f 323 /* acc2 += x[3] * y[1] */
emh203 0:3d9c67d97d6f 324 acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x3 * c0)) >> 32);
emh203 0:3d9c67d97d6f 325 /* acc3 += x[4] * y[1] */
emh203 0:3d9c67d97d6f 326 acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x0 * c0)) >> 32);
emh203 0:3d9c67d97d6f 327
emh203 0:3d9c67d97d6f 328 /* Read y[2] sample */
emh203 0:3d9c67d97d6f 329 c0 = *(py++);
emh203 0:3d9c67d97d6f 330
emh203 0:3d9c67d97d6f 331 /* Read x[5] sample */
emh203 0:3d9c67d97d6f 332 x1 = *(px++);
emh203 0:3d9c67d97d6f 333
emh203 0:3d9c67d97d6f 334 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 335 /* acc0 += x[2] * y[2] */
emh203 0:3d9c67d97d6f 336 acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x2 * c0)) >> 32);
emh203 0:3d9c67d97d6f 337 /* acc1 += x[3] * y[2] */
emh203 0:3d9c67d97d6f 338 acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x3 * c0)) >> 32);
emh203 0:3d9c67d97d6f 339 /* acc2 += x[4] * y[2] */
emh203 0:3d9c67d97d6f 340 acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x0 * c0)) >> 32);
emh203 0:3d9c67d97d6f 341 /* acc3 += x[5] * y[2] */
emh203 0:3d9c67d97d6f 342 acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x1 * c0)) >> 32);
emh203 0:3d9c67d97d6f 343
emh203 0:3d9c67d97d6f 344 /* Read y[3] sample */
emh203 0:3d9c67d97d6f 345 c0 = *(py++);
emh203 0:3d9c67d97d6f 346
emh203 0:3d9c67d97d6f 347 /* Read x[6] sample */
emh203 0:3d9c67d97d6f 348 x2 = *(px++);
emh203 0:3d9c67d97d6f 349
emh203 0:3d9c67d97d6f 350 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 351 /* acc0 += x[3] * y[3] */
emh203 0:3d9c67d97d6f 352 acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x3 * c0)) >> 32);
emh203 0:3d9c67d97d6f 353 /* acc1 += x[4] * y[3] */
emh203 0:3d9c67d97d6f 354 acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x0 * c0)) >> 32);
emh203 0:3d9c67d97d6f 355 /* acc2 += x[5] * y[3] */
emh203 0:3d9c67d97d6f 356 acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x1 * c0)) >> 32);
emh203 0:3d9c67d97d6f 357 /* acc3 += x[6] * y[3] */
emh203 0:3d9c67d97d6f 358 acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x2 * c0)) >> 32);
emh203 0:3d9c67d97d6f 359
emh203 0:3d9c67d97d6f 360
emh203 0:3d9c67d97d6f 361 } while(--k);
emh203 0:3d9c67d97d6f 362
emh203 0:3d9c67d97d6f 363 /* If the srcBLen is not a multiple of 4, compute any remaining MACs here.
emh203 0:3d9c67d97d6f 364 ** No loop unrolling is used. */
emh203 0:3d9c67d97d6f 365 k = srcBLen % 0x4u;
emh203 0:3d9c67d97d6f 366
emh203 0:3d9c67d97d6f 367 while(k > 0u)
emh203 0:3d9c67d97d6f 368 {
emh203 0:3d9c67d97d6f 369 /* Read y[4] sample */
emh203 0:3d9c67d97d6f 370 c0 = *(py++);
emh203 0:3d9c67d97d6f 371
emh203 0:3d9c67d97d6f 372 /* Read x[7] sample */
emh203 0:3d9c67d97d6f 373 x3 = *(px++);
emh203 0:3d9c67d97d6f 374
emh203 0:3d9c67d97d6f 375 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 376 /* acc0 += x[4] * y[4] */
emh203 0:3d9c67d97d6f 377 acc0 = (q31_t) ((((q63_t) acc0 << 32) + ((q63_t) x0 * c0)) >> 32);
emh203 0:3d9c67d97d6f 378 /* acc1 += x[5] * y[4] */
emh203 0:3d9c67d97d6f 379 acc1 = (q31_t) ((((q63_t) acc1 << 32) + ((q63_t) x1 * c0)) >> 32);
emh203 0:3d9c67d97d6f 380 /* acc2 += x[6] * y[4] */
emh203 0:3d9c67d97d6f 381 acc2 = (q31_t) ((((q63_t) acc2 << 32) + ((q63_t) x2 * c0)) >> 32);
emh203 0:3d9c67d97d6f 382 /* acc3 += x[7] * y[4] */
emh203 0:3d9c67d97d6f 383 acc3 = (q31_t) ((((q63_t) acc3 << 32) + ((q63_t) x3 * c0)) >> 32);
emh203 0:3d9c67d97d6f 384
emh203 0:3d9c67d97d6f 385 /* Reuse the present samples for the next MAC */
emh203 0:3d9c67d97d6f 386 x0 = x1;
emh203 0:3d9c67d97d6f 387 x1 = x2;
emh203 0:3d9c67d97d6f 388 x2 = x3;
emh203 0:3d9c67d97d6f 389
emh203 0:3d9c67d97d6f 390 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 391 k--;
emh203 0:3d9c67d97d6f 392 }
emh203 0:3d9c67d97d6f 393
emh203 0:3d9c67d97d6f 394 /* Store the result in the accumulator in the destination buffer. */
emh203 0:3d9c67d97d6f 395 *pOut = (q31_t) (acc0 << 1);
emh203 0:3d9c67d97d6f 396 /* Destination pointer is updated according to the address modifier, inc */
emh203 0:3d9c67d97d6f 397 pOut += inc;
emh203 0:3d9c67d97d6f 398
emh203 0:3d9c67d97d6f 399 *pOut = (q31_t) (acc1 << 1);
emh203 0:3d9c67d97d6f 400 pOut += inc;
emh203 0:3d9c67d97d6f 401
emh203 0:3d9c67d97d6f 402 *pOut = (q31_t) (acc2 << 1);
emh203 0:3d9c67d97d6f 403 pOut += inc;
emh203 0:3d9c67d97d6f 404
emh203 0:3d9c67d97d6f 405 *pOut = (q31_t) (acc3 << 1);
emh203 0:3d9c67d97d6f 406 pOut += inc;
emh203 0:3d9c67d97d6f 407
emh203 0:3d9c67d97d6f 408 /* Increment the pointer pIn1 index, count by 4 */
emh203 0:3d9c67d97d6f 409 count += 4u;
emh203 0:3d9c67d97d6f 410
emh203 0:3d9c67d97d6f 411 /* Update the inputA and inputB pointers for next MAC calculation */
emh203 0:3d9c67d97d6f 412 px = pIn1 + count;
emh203 0:3d9c67d97d6f 413 py = pIn2;
emh203 0:3d9c67d97d6f 414
emh203 0:3d9c67d97d6f 415
emh203 0:3d9c67d97d6f 416 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 417 blkCnt--;
emh203 0:3d9c67d97d6f 418 }
emh203 0:3d9c67d97d6f 419
emh203 0:3d9c67d97d6f 420 /* If the blockSize2 is not a multiple of 4, compute any remaining output samples here.
emh203 0:3d9c67d97d6f 421 ** No loop unrolling is used. */
emh203 0:3d9c67d97d6f 422 blkCnt = blockSize2 % 0x4u;
emh203 0:3d9c67d97d6f 423
emh203 0:3d9c67d97d6f 424 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 425 {
emh203 0:3d9c67d97d6f 426 /* Accumulator is made zero for every iteration */
emh203 0:3d9c67d97d6f 427 sum = 0;
emh203 0:3d9c67d97d6f 428
emh203 0:3d9c67d97d6f 429 /* Apply loop unrolling and compute 4 MACs simultaneously. */
emh203 0:3d9c67d97d6f 430 k = srcBLen >> 2u;
emh203 0:3d9c67d97d6f 431
emh203 0:3d9c67d97d6f 432 /* First part of the processing with loop unrolling. Compute 4 MACs at a time.
emh203 0:3d9c67d97d6f 433 ** a second loop below computes MACs for the remaining 1 to 3 samples. */
emh203 0:3d9c67d97d6f 434 while(k > 0u)
emh203 0:3d9c67d97d6f 435 {
emh203 0:3d9c67d97d6f 436 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 437 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 438 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 439 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 440 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 441 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 442 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 443 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 444 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 445
emh203 0:3d9c67d97d6f 446 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 447 k--;
emh203 0:3d9c67d97d6f 448 }
emh203 0:3d9c67d97d6f 449
emh203 0:3d9c67d97d6f 450 /* If the srcBLen is not a multiple of 4, compute any remaining MACs here.
emh203 0:3d9c67d97d6f 451 ** No loop unrolling is used. */
emh203 0:3d9c67d97d6f 452 k = srcBLen % 0x4u;
emh203 0:3d9c67d97d6f 453
emh203 0:3d9c67d97d6f 454 while(k > 0u)
emh203 0:3d9c67d97d6f 455 {
emh203 0:3d9c67d97d6f 456 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 457 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 458 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 459
emh203 0:3d9c67d97d6f 460 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 461 k--;
emh203 0:3d9c67d97d6f 462 }
emh203 0:3d9c67d97d6f 463
emh203 0:3d9c67d97d6f 464 /* Store the result in the accumulator in the destination buffer. */
emh203 0:3d9c67d97d6f 465 *pOut = sum << 1;
emh203 0:3d9c67d97d6f 466 /* Destination pointer is updated according to the address modifier, inc */
emh203 0:3d9c67d97d6f 467 pOut += inc;
emh203 0:3d9c67d97d6f 468
emh203 0:3d9c67d97d6f 469 /* Increment the MAC count */
emh203 0:3d9c67d97d6f 470 count++;
emh203 0:3d9c67d97d6f 471
emh203 0:3d9c67d97d6f 472 /* Update the inputA and inputB pointers for next MAC calculation */
emh203 0:3d9c67d97d6f 473 px = pIn1 + count;
emh203 0:3d9c67d97d6f 474 py = pIn2;
emh203 0:3d9c67d97d6f 475
emh203 0:3d9c67d97d6f 476
emh203 0:3d9c67d97d6f 477 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 478 blkCnt--;
emh203 0:3d9c67d97d6f 479 }
emh203 0:3d9c67d97d6f 480 }
emh203 0:3d9c67d97d6f 481 else
emh203 0:3d9c67d97d6f 482 {
emh203 0:3d9c67d97d6f 483 /* If the srcBLen is not a multiple of 4,
emh203 0:3d9c67d97d6f 484 * the blockSize2 loop cannot be unrolled by 4 */
emh203 0:3d9c67d97d6f 485 blkCnt = blockSize2;
emh203 0:3d9c67d97d6f 486
emh203 0:3d9c67d97d6f 487 while(blkCnt > 0u)
emh203 0:3d9c67d97d6f 488 {
emh203 0:3d9c67d97d6f 489 /* Accumulator is made zero for every iteration */
emh203 0:3d9c67d97d6f 490 sum = 0;
emh203 0:3d9c67d97d6f 491
emh203 0:3d9c67d97d6f 492 /* Loop over srcBLen */
emh203 0:3d9c67d97d6f 493 k = srcBLen;
emh203 0:3d9c67d97d6f 494
emh203 0:3d9c67d97d6f 495 while(k > 0u)
emh203 0:3d9c67d97d6f 496 {
emh203 0:3d9c67d97d6f 497 /* Perform the multiply-accumulate */
emh203 0:3d9c67d97d6f 498 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 499 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 500
emh203 0:3d9c67d97d6f 501 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 502 k--;
emh203 0:3d9c67d97d6f 503 }
emh203 0:3d9c67d97d6f 504
emh203 0:3d9c67d97d6f 505 /* Store the result in the accumulator in the destination buffer. */
emh203 0:3d9c67d97d6f 506 *pOut = sum << 1;
emh203 0:3d9c67d97d6f 507 /* Destination pointer is updated according to the address modifier, inc */
emh203 0:3d9c67d97d6f 508 pOut += inc;
emh203 0:3d9c67d97d6f 509
emh203 0:3d9c67d97d6f 510 /* Increment the MAC count */
emh203 0:3d9c67d97d6f 511 count++;
emh203 0:3d9c67d97d6f 512
emh203 0:3d9c67d97d6f 513 /* Update the inputA and inputB pointers for next MAC calculation */
emh203 0:3d9c67d97d6f 514 px = pIn1 + count;
emh203 0:3d9c67d97d6f 515 py = pIn2;
emh203 0:3d9c67d97d6f 516
emh203 0:3d9c67d97d6f 517 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 518 blkCnt--;
emh203 0:3d9c67d97d6f 519 }
emh203 0:3d9c67d97d6f 520 }
emh203 0:3d9c67d97d6f 521
emh203 0:3d9c67d97d6f 522 /* --------------------------
emh203 0:3d9c67d97d6f 523 * Initializations of stage3
emh203 0:3d9c67d97d6f 524 * -------------------------*/
emh203 0:3d9c67d97d6f 525
emh203 0:3d9c67d97d6f 526 /* sum += x[srcALen-srcBLen+1] * y[0] + x[srcALen-srcBLen+2] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
emh203 0:3d9c67d97d6f 527 * sum += x[srcALen-srcBLen+2] * y[0] + x[srcALen-srcBLen+3] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
emh203 0:3d9c67d97d6f 528 * ....
emh203 0:3d9c67d97d6f 529 * sum += x[srcALen-2] * y[0] + x[srcALen-1] * y[1]
emh203 0:3d9c67d97d6f 530 * sum += x[srcALen-1] * y[0]
emh203 0:3d9c67d97d6f 531 */
emh203 0:3d9c67d97d6f 532
emh203 0:3d9c67d97d6f 533 /* In this stage the MAC operations are decreased by 1 for every iteration.
emh203 0:3d9c67d97d6f 534 The count variable holds the number of MAC operations performed */
emh203 0:3d9c67d97d6f 535 count = srcBLen - 1u;
emh203 0:3d9c67d97d6f 536
emh203 0:3d9c67d97d6f 537 /* Working pointer of inputA */
emh203 0:3d9c67d97d6f 538 pSrc1 = ((pIn1 + srcALen) - srcBLen) + 1u;
emh203 0:3d9c67d97d6f 539 px = pSrc1;
emh203 0:3d9c67d97d6f 540
emh203 0:3d9c67d97d6f 541 /* Working pointer of inputB */
emh203 0:3d9c67d97d6f 542 py = pIn2;
emh203 0:3d9c67d97d6f 543
emh203 0:3d9c67d97d6f 544 /* -------------------
emh203 0:3d9c67d97d6f 545 * Stage3 process
emh203 0:3d9c67d97d6f 546 * ------------------*/
emh203 0:3d9c67d97d6f 547
emh203 0:3d9c67d97d6f 548 while(blockSize3 > 0u)
emh203 0:3d9c67d97d6f 549 {
emh203 0:3d9c67d97d6f 550 /* Accumulator is made zero for every iteration */
emh203 0:3d9c67d97d6f 551 sum = 0;
emh203 0:3d9c67d97d6f 552
emh203 0:3d9c67d97d6f 553 /* Apply loop unrolling and compute 4 MACs simultaneously. */
emh203 0:3d9c67d97d6f 554 k = count >> 2u;
emh203 0:3d9c67d97d6f 555
emh203 0:3d9c67d97d6f 556 /* First part of the processing with loop unrolling. Compute 4 MACs at a time.
emh203 0:3d9c67d97d6f 557 ** a second loop below computes MACs for the remaining 1 to 3 samples. */
emh203 0:3d9c67d97d6f 558 while(k > 0u)
emh203 0:3d9c67d97d6f 559 {
emh203 0:3d9c67d97d6f 560 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 561 /* sum += x[srcALen - srcBLen + 4] * y[3] */
emh203 0:3d9c67d97d6f 562 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 563 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 564 /* sum += x[srcALen - srcBLen + 3] * y[2] */
emh203 0:3d9c67d97d6f 565 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 566 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 567 /* sum += x[srcALen - srcBLen + 2] * y[1] */
emh203 0:3d9c67d97d6f 568 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 569 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 570 /* sum += x[srcALen - srcBLen + 1] * y[0] */
emh203 0:3d9c67d97d6f 571 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 572 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 573
emh203 0:3d9c67d97d6f 574 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 575 k--;
emh203 0:3d9c67d97d6f 576 }
emh203 0:3d9c67d97d6f 577
emh203 0:3d9c67d97d6f 578 /* If the count is not a multiple of 4, compute any remaining MACs here.
emh203 0:3d9c67d97d6f 579 ** No loop unrolling is used. */
emh203 0:3d9c67d97d6f 580 k = count % 0x4u;
emh203 0:3d9c67d97d6f 581
emh203 0:3d9c67d97d6f 582 while(k > 0u)
emh203 0:3d9c67d97d6f 583 {
emh203 0:3d9c67d97d6f 584 /* Perform the multiply-accumulates */
emh203 0:3d9c67d97d6f 585 sum = (q31_t) ((((q63_t) sum << 32) +
emh203 0:3d9c67d97d6f 586 ((q63_t) * px++ * (*py++))) >> 32);
emh203 0:3d9c67d97d6f 587
emh203 0:3d9c67d97d6f 588 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 589 k--;
emh203 0:3d9c67d97d6f 590 }
emh203 0:3d9c67d97d6f 591
emh203 0:3d9c67d97d6f 592 /* Store the result in the accumulator in the destination buffer. */
emh203 0:3d9c67d97d6f 593 *pOut = sum << 1;
emh203 0:3d9c67d97d6f 594 /* Destination pointer is updated according to the address modifier, inc */
emh203 0:3d9c67d97d6f 595 pOut += inc;
emh203 0:3d9c67d97d6f 596
emh203 0:3d9c67d97d6f 597 /* Update the inputA and inputB pointers for next MAC calculation */
emh203 0:3d9c67d97d6f 598 px = ++pSrc1;
emh203 0:3d9c67d97d6f 599 py = pIn2;
emh203 0:3d9c67d97d6f 600
emh203 0:3d9c67d97d6f 601 /* Decrement the MAC count */
emh203 0:3d9c67d97d6f 602 count--;
emh203 0:3d9c67d97d6f 603
emh203 0:3d9c67d97d6f 604 /* Decrement the loop counter */
emh203 0:3d9c67d97d6f 605 blockSize3--;
emh203 0:3d9c67d97d6f 606 }
emh203 0:3d9c67d97d6f 607
emh203 0:3d9c67d97d6f 608 }
emh203 0:3d9c67d97d6f 609
emh203 0:3d9c67d97d6f 610 /**
emh203 0:3d9c67d97d6f 611 * @} end of Corr group
emh203 0:3d9c67d97d6f 612 */