1320 rivejä
36 KiB
C
1320 rivejä
36 KiB
C
/* ----------------------------------------------------------------------
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* Copyright (C) 2010-2013 ARM Limited. All rights reserved.
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*
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* $Date: 17. January 2013
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* $Revision: V1.4.1
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*
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* Project: CMSIS DSP Library
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* Title: arm_correlate_fast_q15.c
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*
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* Description: Fast Q15 Correlation.
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*
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* Target Processor: Cortex-M4/Cortex-M3
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* - Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* - Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* - Neither the name of ARM LIMITED nor the names of its contributors
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* may be used to endorse or promote products derived from this
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* software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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* -------------------------------------------------------------------- */
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#include "arm_math.h"
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/**
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* @ingroup groupFilters
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*/
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/**
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* @addtogroup Corr
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* @{
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*/
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/**
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* @brief Correlation of Q15 sequences (fast version) for Cortex-M3 and Cortex-M4.
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* @param[in] *pSrcA points to the first input sequence.
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* @param[in] srcALen length of the first input sequence.
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* @param[in] *pSrcB points to the second input sequence.
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* @param[in] srcBLen length of the second input sequence.
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* @param[out] *pDst points to the location where the output result is written. Length 2 * max(srcALen, srcBLen) - 1.
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* @return none.
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*
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* <b>Scaling and Overflow Behavior:</b>
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*
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* \par
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* This fast version uses a 32-bit accumulator with 2.30 format.
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* The accumulator maintains full precision of the intermediate multiplication results but provides only a single guard bit.
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* There is no saturation on intermediate additions.
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* Thus, if the accumulator overflows it wraps around and distorts the result.
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* The input signals should be scaled down to avoid intermediate overflows.
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* Scale down one of the inputs by 1/min(srcALen, srcBLen) to avoid overflow since a
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* maximum of min(srcALen, srcBLen) number of additions is carried internally.
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* The 2.30 accumulator is right shifted by 15 bits and then saturated to 1.15 format to yield the final result.
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*
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* \par
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* See <code>arm_correlate_q15()</code> for a slower implementation of this function which uses a 64-bit accumulator to avoid wrap around distortion.
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*/
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void arm_correlate_fast_q15(
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q15_t * pSrcA,
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uint32_t srcALen,
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q15_t * pSrcB,
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uint32_t srcBLen,
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q15_t * pDst)
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{
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#ifndef UNALIGNED_SUPPORT_DISABLE
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q15_t *pIn1; /* inputA pointer */
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q15_t *pIn2; /* inputB pointer */
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q15_t *pOut = pDst; /* output pointer */
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q31_t sum, acc0, acc1, acc2, acc3; /* Accumulators */
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q15_t *px; /* Intermediate inputA pointer */
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q15_t *py; /* Intermediate inputB pointer */
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q15_t *pSrc1; /* Intermediate pointers */
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q31_t x0, x1, x2, x3, c0; /* temporary variables for holding input and coefficient values */
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uint32_t j, k = 0u, count, blkCnt, outBlockSize, blockSize1, blockSize2, blockSize3; /* loop counter */
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int32_t inc = 1; /* Destination address modifier */
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/* The algorithm implementation is based on the lengths of the inputs. */
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/* srcB is always made to slide across srcA. */
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/* So srcBLen is always considered as shorter or equal to srcALen */
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/* But CORR(x, y) is reverse of CORR(y, x) */
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/* So, when srcBLen > srcALen, output pointer is made to point to the end of the output buffer */
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/* and the destination pointer modifier, inc is set to -1 */
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/* If srcALen > srcBLen, zero pad has to be done to srcB to make the two inputs of same length */
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/* But to improve the performance,
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* we include zeroes in the output instead of zero padding either of the the inputs*/
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/* If srcALen > srcBLen,
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* (srcALen - srcBLen) zeroes has to included in the starting of the output buffer */
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/* If srcALen < srcBLen,
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* (srcALen - srcBLen) zeroes has to included in the ending of the output buffer */
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if(srcALen >= srcBLen)
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{
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/* Initialization of inputA pointer */
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pIn1 = (pSrcA);
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/* Initialization of inputB pointer */
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pIn2 = (pSrcB);
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/* Number of output samples is calculated */
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outBlockSize = (2u * srcALen) - 1u;
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/* When srcALen > srcBLen, zero padding is done to srcB
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* to make their lengths equal.
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* Instead, (outBlockSize - (srcALen + srcBLen - 1))
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* number of output samples are made zero */
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j = outBlockSize - (srcALen + (srcBLen - 1u));
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/* Updating the pointer position to non zero value */
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pOut += j;
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}
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else
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{
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/* Initialization of inputA pointer */
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pIn1 = (pSrcB);
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/* Initialization of inputB pointer */
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pIn2 = (pSrcA);
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/* srcBLen is always considered as shorter or equal to srcALen */
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j = srcBLen;
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srcBLen = srcALen;
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srcALen = j;
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/* CORR(x, y) = Reverse order(CORR(y, x)) */
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/* Hence set the destination pointer to point to the last output sample */
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pOut = pDst + ((srcALen + srcBLen) - 2u);
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/* Destination address modifier is set to -1 */
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inc = -1;
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}
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/* The function is internally
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* divided into three parts according to the number of multiplications that has to be
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* taken place between inputA samples and inputB samples. In the first part of the
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* algorithm, the multiplications increase by one for every iteration.
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* In the second part of the algorithm, srcBLen number of multiplications are done.
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* In the third part of the algorithm, the multiplications decrease by one
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* for every iteration.*/
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/* The algorithm is implemented in three stages.
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* The loop counters of each stage is initiated here. */
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blockSize1 = srcBLen - 1u;
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blockSize2 = srcALen - (srcBLen - 1u);
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blockSize3 = blockSize1;
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/* --------------------------
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* Initializations of stage1
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* -------------------------*/
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/* sum = x[0] * y[srcBlen - 1]
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* sum = x[0] * y[srcBlen - 2] + x[1] * y[srcBlen - 1]
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* ....
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* sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen - 1] * y[srcBLen - 1]
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*/
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/* In this stage the MAC operations are increased by 1 for every iteration.
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The count variable holds the number of MAC operations performed */
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count = 1u;
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/* Working pointer of inputA */
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px = pIn1;
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/* Working pointer of inputB */
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pSrc1 = pIn2 + (srcBLen - 1u);
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py = pSrc1;
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/* ------------------------
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* Stage1 process
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* ----------------------*/
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/* The first loop starts here */
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while(blockSize1 > 0u)
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{
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/* Accumulator is made zero for every iteration */
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sum = 0;
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/* Apply loop unrolling and compute 4 MACs simultaneously. */
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k = count >> 2;
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/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
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** a second loop below computes MACs for the remaining 1 to 3 samples. */
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while(k > 0u)
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{
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/* x[0] * y[srcBLen - 4] , x[1] * y[srcBLen - 3] */
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sum = __SMLAD(*__SIMD32(px)++, *__SIMD32(py)++, sum);
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/* x[3] * y[srcBLen - 1] , x[2] * y[srcBLen - 2] */
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sum = __SMLAD(*__SIMD32(px)++, *__SIMD32(py)++, sum);
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/* Decrement the loop counter */
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k--;
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}
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/* If the count is not a multiple of 4, compute any remaining MACs here.
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** No loop unrolling is used. */
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k = count % 0x4u;
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while(k > 0u)
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{
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/* Perform the multiply-accumulates */
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/* x[0] * y[srcBLen - 1] */
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sum = __SMLAD(*px++, *py++, sum);
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/* Decrement the loop counter */
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k--;
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}
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/* Store the result in the accumulator in the destination buffer. */
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*pOut = (q15_t) (sum >> 15);
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/* Destination pointer is updated according to the address modifier, inc */
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pOut += inc;
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/* Update the inputA and inputB pointers for next MAC calculation */
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py = pSrc1 - count;
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px = pIn1;
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/* Increment the MAC count */
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count++;
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/* Decrement the loop counter */
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blockSize1--;
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}
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/* --------------------------
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* Initializations of stage2
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* ------------------------*/
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/* sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen-1] * y[srcBLen-1]
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* sum = x[1] * y[0] + x[2] * y[1] +...+ x[srcBLen] * y[srcBLen-1]
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* ....
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* sum = x[srcALen-srcBLen-2] * y[0] + x[srcALen-srcBLen-1] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
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*/
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/* Working pointer of inputA */
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px = pIn1;
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/* Working pointer of inputB */
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py = pIn2;
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/* count is index by which the pointer pIn1 to be incremented */
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count = 0u;
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/* -------------------
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* Stage2 process
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* ------------------*/
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/* Stage2 depends on srcBLen as in this stage srcBLen number of MACS are performed.
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* So, to loop unroll over blockSize2,
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* srcBLen should be greater than or equal to 4, to loop unroll the srcBLen loop */
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if(srcBLen >= 4u)
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{
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/* Loop unroll over blockSize2, by 4 */
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blkCnt = blockSize2 >> 2u;
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while(blkCnt > 0u)
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{
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/* Set all accumulators to zero */
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acc0 = 0;
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acc1 = 0;
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acc2 = 0;
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acc3 = 0;
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/* read x[0], x[1] samples */
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x0 = *__SIMD32(px);
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/* read x[1], x[2] samples */
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x1 = _SIMD32_OFFSET(px + 1);
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px += 2u;
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/* Apply loop unrolling and compute 4 MACs simultaneously. */
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k = srcBLen >> 2u;
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/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
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** a second loop below computes MACs for the remaining 1 to 3 samples. */
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do
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{
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/* Read the first two inputB samples using SIMD:
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* y[0] and y[1] */
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c0 = *__SIMD32(py)++;
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/* acc0 += x[0] * y[0] + x[1] * y[1] */
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acc0 = __SMLAD(x0, c0, acc0);
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/* acc1 += x[1] * y[0] + x[2] * y[1] */
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acc1 = __SMLAD(x1, c0, acc1);
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/* Read x[2], x[3] */
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x2 = *__SIMD32(px);
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/* Read x[3], x[4] */
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x3 = _SIMD32_OFFSET(px + 1);
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/* acc2 += x[2] * y[0] + x[3] * y[1] */
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acc2 = __SMLAD(x2, c0, acc2);
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/* acc3 += x[3] * y[0] + x[4] * y[1] */
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acc3 = __SMLAD(x3, c0, acc3);
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/* Read y[2] and y[3] */
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c0 = *__SIMD32(py)++;
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/* acc0 += x[2] * y[2] + x[3] * y[3] */
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acc0 = __SMLAD(x2, c0, acc0);
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/* acc1 += x[3] * y[2] + x[4] * y[3] */
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acc1 = __SMLAD(x3, c0, acc1);
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/* Read x[4], x[5] */
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x0 = _SIMD32_OFFSET(px + 2);
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/* Read x[5], x[6] */
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x1 = _SIMD32_OFFSET(px + 3);
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px += 4u;
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/* acc2 += x[4] * y[2] + x[5] * y[3] */
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acc2 = __SMLAD(x0, c0, acc2);
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/* acc3 += x[5] * y[2] + x[6] * y[3] */
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acc3 = __SMLAD(x1, c0, acc3);
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} while(--k);
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/* For the next MAC operations, SIMD is not used
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* So, the 16 bit pointer if inputB, py is updated */
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/* If the srcBLen is not a multiple of 4, compute any remaining MACs here.
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** No loop unrolling is used. */
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k = srcBLen % 0x4u;
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if(k == 1u)
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{
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/* Read y[4] */
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c0 = *py;
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#ifdef ARM_MATH_BIG_ENDIAN
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c0 = c0 << 16u;
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#else
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c0 = c0 & 0x0000FFFF;
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#endif /* #ifdef ARM_MATH_BIG_ENDIAN */
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/* Read x[7] */
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x3 = *__SIMD32(px);
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px++;
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/* Perform the multiply-accumulates */
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acc0 = __SMLAD(x0, c0, acc0);
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acc1 = __SMLAD(x1, c0, acc1);
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acc2 = __SMLADX(x1, c0, acc2);
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acc3 = __SMLADX(x3, c0, acc3);
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}
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if(k == 2u)
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{
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/* Read y[4], y[5] */
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c0 = *__SIMD32(py);
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/* Read x[7], x[8] */
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x3 = *__SIMD32(px);
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/* Read x[9] */
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x2 = _SIMD32_OFFSET(px + 1);
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px += 2u;
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/* Perform the multiply-accumulates */
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acc0 = __SMLAD(x0, c0, acc0);
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acc1 = __SMLAD(x1, c0, acc1);
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acc2 = __SMLAD(x3, c0, acc2);
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acc3 = __SMLAD(x2, c0, acc3);
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}
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if(k == 3u)
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{
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/* Read y[4], y[5] */
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c0 = *__SIMD32(py)++;
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/* Read x[7], x[8] */
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x3 = *__SIMD32(px);
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/* Read x[9] */
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x2 = _SIMD32_OFFSET(px + 1);
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/* Perform the multiply-accumulates */
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acc0 = __SMLAD(x0, c0, acc0);
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acc1 = __SMLAD(x1, c0, acc1);
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acc2 = __SMLAD(x3, c0, acc2);
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acc3 = __SMLAD(x2, c0, acc3);
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c0 = (*py);
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/* Read y[6] */
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#ifdef ARM_MATH_BIG_ENDIAN
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c0 = c0 << 16u;
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#else
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c0 = c0 & 0x0000FFFF;
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#endif /* #ifdef ARM_MATH_BIG_ENDIAN */
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/* Read x[10] */
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x3 = _SIMD32_OFFSET(px + 2);
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px += 3u;
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/* Perform the multiply-accumulates */
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acc0 = __SMLADX(x1, c0, acc0);
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acc1 = __SMLAD(x2, c0, acc1);
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acc2 = __SMLADX(x2, c0, acc2);
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acc3 = __SMLADX(x3, c0, acc3);
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}
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/* Store the result in the accumulator in the destination buffer. */
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*pOut = (q15_t) (acc0 >> 15);
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/* Destination pointer is updated according to the address modifier, inc */
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pOut += inc;
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*pOut = (q15_t) (acc1 >> 15);
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pOut += inc;
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*pOut = (q15_t) (acc2 >> 15);
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pOut += inc;
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*pOut = (q15_t) (acc3 >> 15);
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pOut += inc;
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/* Increment the pointer pIn1 index, count by 1 */
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count += 4u;
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/* Update the inputA and inputB pointers for next MAC calculation */
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px = pIn1 + count;
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py = pIn2;
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/* Decrement the loop counter */
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blkCnt--;
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}
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/* If the blockSize2 is not a multiple of 4, compute any remaining output samples here.
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** No loop unrolling is used. */
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blkCnt = blockSize2 % 0x4u;
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while(blkCnt > 0u)
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{
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/* Accumulator is made zero for every iteration */
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sum = 0;
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/* Apply loop unrolling and compute 4 MACs simultaneously. */
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k = srcBLen >> 2u;
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/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
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** a second loop below computes MACs for the remaining 1 to 3 samples. */
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while(k > 0u)
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{
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/* Perform the multiply-accumulates */
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sum += ((q31_t) * px++ * *py++);
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sum += ((q31_t) * px++ * *py++);
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sum += ((q31_t) * px++ * *py++);
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sum += ((q31_t) * px++ * *py++);
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/* Decrement the loop counter */
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k--;
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}
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/* If the srcBLen is not a multiple of 4, compute any remaining MACs here.
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** No loop unrolling is used. */
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k = srcBLen % 0x4u;
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while(k > 0u)
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{
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/* Perform the multiply-accumulates */
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sum += ((q31_t) * px++ * *py++);
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/* Decrement the loop counter */
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k--;
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}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (sum >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
/* Increment the pointer pIn1 index, count by 1 */
|
|
count++;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
px = pIn1 + count;
|
|
py = pIn2;
|
|
|
|
/* Decrement the loop counter */
|
|
blkCnt--;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* If the srcBLen is not a multiple of 4,
|
|
* the blockSize2 loop cannot be unrolled by 4 */
|
|
blkCnt = blockSize2;
|
|
|
|
while(blkCnt > 0u)
|
|
{
|
|
/* Accumulator is made zero for every iteration */
|
|
sum = 0;
|
|
|
|
/* Loop over srcBLen */
|
|
k = srcBLen;
|
|
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulate */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (sum >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
/* Increment the MAC count */
|
|
count++;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
px = pIn1 + count;
|
|
py = pIn2;
|
|
|
|
/* Decrement the loop counter */
|
|
blkCnt--;
|
|
}
|
|
}
|
|
|
|
/* --------------------------
|
|
* Initializations of stage3
|
|
* -------------------------*/
|
|
|
|
/* sum += x[srcALen-srcBLen+1] * y[0] + x[srcALen-srcBLen+2] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
|
|
* sum += x[srcALen-srcBLen+2] * y[0] + x[srcALen-srcBLen+3] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
|
|
* ....
|
|
* sum += x[srcALen-2] * y[0] + x[srcALen-1] * y[1]
|
|
* sum += x[srcALen-1] * y[0]
|
|
*/
|
|
|
|
/* In this stage the MAC operations are decreased by 1 for every iteration.
|
|
The count variable holds the number of MAC operations performed */
|
|
count = srcBLen - 1u;
|
|
|
|
/* Working pointer of inputA */
|
|
pSrc1 = (pIn1 + srcALen) - (srcBLen - 1u);
|
|
px = pSrc1;
|
|
|
|
/* Working pointer of inputB */
|
|
py = pIn2;
|
|
|
|
/* -------------------
|
|
* Stage3 process
|
|
* ------------------*/
|
|
|
|
while(blockSize3 > 0u)
|
|
{
|
|
/* Accumulator is made zero for every iteration */
|
|
sum = 0;
|
|
|
|
/* Apply loop unrolling and compute 4 MACs simultaneously. */
|
|
k = count >> 2u;
|
|
|
|
/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
|
|
** a second loop below computes MACs for the remaining 1 to 3 samples. */
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulates */
|
|
/* sum += x[srcALen - srcBLen + 4] * y[3] , sum += x[srcALen - srcBLen + 3] * y[2] */
|
|
sum = __SMLAD(*__SIMD32(px)++, *__SIMD32(py)++, sum);
|
|
/* sum += x[srcALen - srcBLen + 2] * y[1] , sum += x[srcALen - srcBLen + 1] * y[0] */
|
|
sum = __SMLAD(*__SIMD32(px)++, *__SIMD32(py)++, sum);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* If the count is not a multiple of 4, compute any remaining MACs here.
|
|
** No loop unrolling is used. */
|
|
k = count % 0x4u;
|
|
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulates */
|
|
sum = __SMLAD(*px++, *py++, sum);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (sum >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
px = ++pSrc1;
|
|
py = pIn2;
|
|
|
|
/* Decrement the MAC count */
|
|
count--;
|
|
|
|
/* Decrement the loop counter */
|
|
blockSize3--;
|
|
}
|
|
|
|
#else
|
|
|
|
q15_t *pIn1; /* inputA pointer */
|
|
q15_t *pIn2; /* inputB pointer */
|
|
q15_t *pOut = pDst; /* output pointer */
|
|
q31_t sum, acc0, acc1, acc2, acc3; /* Accumulators */
|
|
q15_t *px; /* Intermediate inputA pointer */
|
|
q15_t *py; /* Intermediate inputB pointer */
|
|
q15_t *pSrc1; /* Intermediate pointers */
|
|
q31_t x0, x1, x2, x3, c0; /* temporary variables for holding input and coefficient values */
|
|
uint32_t j, k = 0u, count, blkCnt, outBlockSize, blockSize1, blockSize2, blockSize3; /* loop counter */
|
|
int32_t inc = 1; /* Destination address modifier */
|
|
q15_t a, b;
|
|
|
|
|
|
/* The algorithm implementation is based on the lengths of the inputs. */
|
|
/* srcB is always made to slide across srcA. */
|
|
/* So srcBLen is always considered as shorter or equal to srcALen */
|
|
/* But CORR(x, y) is reverse of CORR(y, x) */
|
|
/* So, when srcBLen > srcALen, output pointer is made to point to the end of the output buffer */
|
|
/* and the destination pointer modifier, inc is set to -1 */
|
|
/* If srcALen > srcBLen, zero pad has to be done to srcB to make the two inputs of same length */
|
|
/* But to improve the performance,
|
|
* we include zeroes in the output instead of zero padding either of the the inputs*/
|
|
/* If srcALen > srcBLen,
|
|
* (srcALen - srcBLen) zeroes has to included in the starting of the output buffer */
|
|
/* If srcALen < srcBLen,
|
|
* (srcALen - srcBLen) zeroes has to included in the ending of the output buffer */
|
|
if(srcALen >= srcBLen)
|
|
{
|
|
/* Initialization of inputA pointer */
|
|
pIn1 = (pSrcA);
|
|
|
|
/* Initialization of inputB pointer */
|
|
pIn2 = (pSrcB);
|
|
|
|
/* Number of output samples is calculated */
|
|
outBlockSize = (2u * srcALen) - 1u;
|
|
|
|
/* When srcALen > srcBLen, zero padding is done to srcB
|
|
* to make their lengths equal.
|
|
* Instead, (outBlockSize - (srcALen + srcBLen - 1))
|
|
* number of output samples are made zero */
|
|
j = outBlockSize - (srcALen + (srcBLen - 1u));
|
|
|
|
/* Updating the pointer position to non zero value */
|
|
pOut += j;
|
|
|
|
}
|
|
else
|
|
{
|
|
/* Initialization of inputA pointer */
|
|
pIn1 = (pSrcB);
|
|
|
|
/* Initialization of inputB pointer */
|
|
pIn2 = (pSrcA);
|
|
|
|
/* srcBLen is always considered as shorter or equal to srcALen */
|
|
j = srcBLen;
|
|
srcBLen = srcALen;
|
|
srcALen = j;
|
|
|
|
/* CORR(x, y) = Reverse order(CORR(y, x)) */
|
|
/* Hence set the destination pointer to point to the last output sample */
|
|
pOut = pDst + ((srcALen + srcBLen) - 2u);
|
|
|
|
/* Destination address modifier is set to -1 */
|
|
inc = -1;
|
|
|
|
}
|
|
|
|
/* The function is internally
|
|
* divided into three parts according to the number of multiplications that has to be
|
|
* taken place between inputA samples and inputB samples. In the first part of the
|
|
* algorithm, the multiplications increase by one for every iteration.
|
|
* In the second part of the algorithm, srcBLen number of multiplications are done.
|
|
* In the third part of the algorithm, the multiplications decrease by one
|
|
* for every iteration.*/
|
|
/* The algorithm is implemented in three stages.
|
|
* The loop counters of each stage is initiated here. */
|
|
blockSize1 = srcBLen - 1u;
|
|
blockSize2 = srcALen - (srcBLen - 1u);
|
|
blockSize3 = blockSize1;
|
|
|
|
/* --------------------------
|
|
* Initializations of stage1
|
|
* -------------------------*/
|
|
|
|
/* sum = x[0] * y[srcBlen - 1]
|
|
* sum = x[0] * y[srcBlen - 2] + x[1] * y[srcBlen - 1]
|
|
* ....
|
|
* sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen - 1] * y[srcBLen - 1]
|
|
*/
|
|
|
|
/* In this stage the MAC operations are increased by 1 for every iteration.
|
|
The count variable holds the number of MAC operations performed */
|
|
count = 1u;
|
|
|
|
/* Working pointer of inputA */
|
|
px = pIn1;
|
|
|
|
/* Working pointer of inputB */
|
|
pSrc1 = pIn2 + (srcBLen - 1u);
|
|
py = pSrc1;
|
|
|
|
/* ------------------------
|
|
* Stage1 process
|
|
* ----------------------*/
|
|
|
|
/* The first loop starts here */
|
|
while(blockSize1 > 0u)
|
|
{
|
|
/* Accumulator is made zero for every iteration */
|
|
sum = 0;
|
|
|
|
/* Apply loop unrolling and compute 4 MACs simultaneously. */
|
|
k = count >> 2;
|
|
|
|
/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
|
|
** a second loop below computes MACs for the remaining 1 to 3 samples. */
|
|
while(k > 0u)
|
|
{
|
|
/* x[0] * y[srcBLen - 4] , x[1] * y[srcBLen - 3] */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* If the count is not a multiple of 4, compute any remaining MACs here.
|
|
** No loop unrolling is used. */
|
|
k = count % 0x4u;
|
|
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulates */
|
|
/* x[0] * y[srcBLen - 1] */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (sum >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
py = pSrc1 - count;
|
|
px = pIn1;
|
|
|
|
/* Increment the MAC count */
|
|
count++;
|
|
|
|
/* Decrement the loop counter */
|
|
blockSize1--;
|
|
}
|
|
|
|
/* --------------------------
|
|
* Initializations of stage2
|
|
* ------------------------*/
|
|
|
|
/* sum = x[0] * y[0] + x[1] * y[1] +...+ x[srcBLen-1] * y[srcBLen-1]
|
|
* sum = x[1] * y[0] + x[2] * y[1] +...+ x[srcBLen] * y[srcBLen-1]
|
|
* ....
|
|
* sum = x[srcALen-srcBLen-2] * y[0] + x[srcALen-srcBLen-1] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
|
|
*/
|
|
|
|
/* Working pointer of inputA */
|
|
px = pIn1;
|
|
|
|
/* Working pointer of inputB */
|
|
py = pIn2;
|
|
|
|
/* count is index by which the pointer pIn1 to be incremented */
|
|
count = 0u;
|
|
|
|
/* -------------------
|
|
* Stage2 process
|
|
* ------------------*/
|
|
|
|
/* Stage2 depends on srcBLen as in this stage srcBLen number of MACS are performed.
|
|
* So, to loop unroll over blockSize2,
|
|
* srcBLen should be greater than or equal to 4, to loop unroll the srcBLen loop */
|
|
if(srcBLen >= 4u)
|
|
{
|
|
/* Loop unroll over blockSize2, by 4 */
|
|
blkCnt = blockSize2 >> 2u;
|
|
|
|
while(blkCnt > 0u)
|
|
{
|
|
/* Set all accumulators to zero */
|
|
acc0 = 0;
|
|
acc1 = 0;
|
|
acc2 = 0;
|
|
acc3 = 0;
|
|
|
|
/* read x[0], x[1], x[2] samples */
|
|
a = *px;
|
|
b = *(px + 1);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
x0 = __PKHBT(a, b, 16);
|
|
a = *(px + 2);
|
|
x1 = __PKHBT(b, a, 16);
|
|
|
|
#else
|
|
|
|
x0 = __PKHBT(b, a, 16);
|
|
a = *(px + 2);
|
|
x1 = __PKHBT(a, b, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
px += 2u;
|
|
|
|
/* Apply loop unrolling and compute 4 MACs simultaneously. */
|
|
k = srcBLen >> 2u;
|
|
|
|
/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
|
|
** a second loop below computes MACs for the remaining 1 to 3 samples. */
|
|
do
|
|
{
|
|
/* Read the first two inputB samples using SIMD:
|
|
* y[0] and y[1] */
|
|
a = *py;
|
|
b = *(py + 1);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
c0 = __PKHBT(a, b, 16);
|
|
|
|
#else
|
|
|
|
c0 = __PKHBT(b, a, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
/* acc0 += x[0] * y[0] + x[1] * y[1] */
|
|
acc0 = __SMLAD(x0, c0, acc0);
|
|
|
|
/* acc1 += x[1] * y[0] + x[2] * y[1] */
|
|
acc1 = __SMLAD(x1, c0, acc1);
|
|
|
|
/* Read x[2], x[3], x[4] */
|
|
a = *px;
|
|
b = *(px + 1);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
x2 = __PKHBT(a, b, 16);
|
|
a = *(px + 2);
|
|
x3 = __PKHBT(b, a, 16);
|
|
|
|
#else
|
|
|
|
x2 = __PKHBT(b, a, 16);
|
|
a = *(px + 2);
|
|
x3 = __PKHBT(a, b, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
/* acc2 += x[2] * y[0] + x[3] * y[1] */
|
|
acc2 = __SMLAD(x2, c0, acc2);
|
|
|
|
/* acc3 += x[3] * y[0] + x[4] * y[1] */
|
|
acc3 = __SMLAD(x3, c0, acc3);
|
|
|
|
/* Read y[2] and y[3] */
|
|
a = *(py + 2);
|
|
b = *(py + 3);
|
|
|
|
py += 4u;
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
c0 = __PKHBT(a, b, 16);
|
|
|
|
#else
|
|
|
|
c0 = __PKHBT(b, a, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
/* acc0 += x[2] * y[2] + x[3] * y[3] */
|
|
acc0 = __SMLAD(x2, c0, acc0);
|
|
|
|
/* acc1 += x[3] * y[2] + x[4] * y[3] */
|
|
acc1 = __SMLAD(x3, c0, acc1);
|
|
|
|
/* Read x[4], x[5], x[6] */
|
|
a = *(px + 2);
|
|
b = *(px + 3);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
x0 = __PKHBT(a, b, 16);
|
|
a = *(px + 4);
|
|
x1 = __PKHBT(b, a, 16);
|
|
|
|
#else
|
|
|
|
x0 = __PKHBT(b, a, 16);
|
|
a = *(px + 4);
|
|
x1 = __PKHBT(a, b, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
px += 4u;
|
|
|
|
/* acc2 += x[4] * y[2] + x[5] * y[3] */
|
|
acc2 = __SMLAD(x0, c0, acc2);
|
|
|
|
/* acc3 += x[5] * y[2] + x[6] * y[3] */
|
|
acc3 = __SMLAD(x1, c0, acc3);
|
|
|
|
} while(--k);
|
|
|
|
/* For the next MAC operations, SIMD is not used
|
|
* So, the 16 bit pointer if inputB, py is updated */
|
|
|
|
/* If the srcBLen is not a multiple of 4, compute any remaining MACs here.
|
|
** No loop unrolling is used. */
|
|
k = srcBLen % 0x4u;
|
|
|
|
if(k == 1u)
|
|
{
|
|
/* Read y[4] */
|
|
c0 = *py;
|
|
#ifdef ARM_MATH_BIG_ENDIAN
|
|
|
|
c0 = c0 << 16u;
|
|
|
|
#else
|
|
|
|
c0 = c0 & 0x0000FFFF;
|
|
|
|
#endif /* #ifdef ARM_MATH_BIG_ENDIAN */
|
|
|
|
/* Read x[7] */
|
|
a = *px;
|
|
b = *(px + 1);
|
|
|
|
px++;;
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
x3 = __PKHBT(a, b, 16);
|
|
|
|
#else
|
|
|
|
x3 = __PKHBT(b, a, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
px++;
|
|
|
|
/* Perform the multiply-accumulates */
|
|
acc0 = __SMLAD(x0, c0, acc0);
|
|
acc1 = __SMLAD(x1, c0, acc1);
|
|
acc2 = __SMLADX(x1, c0, acc2);
|
|
acc3 = __SMLADX(x3, c0, acc3);
|
|
}
|
|
|
|
if(k == 2u)
|
|
{
|
|
/* Read y[4], y[5] */
|
|
a = *py;
|
|
b = *(py + 1);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
c0 = __PKHBT(a, b, 16);
|
|
|
|
#else
|
|
|
|
c0 = __PKHBT(b, a, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
/* Read x[7], x[8], x[9] */
|
|
a = *px;
|
|
b = *(px + 1);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
x3 = __PKHBT(a, b, 16);
|
|
a = *(px + 2);
|
|
x2 = __PKHBT(b, a, 16);
|
|
|
|
#else
|
|
|
|
x3 = __PKHBT(b, a, 16);
|
|
a = *(px + 2);
|
|
x2 = __PKHBT(a, b, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
px += 2u;
|
|
|
|
/* Perform the multiply-accumulates */
|
|
acc0 = __SMLAD(x0, c0, acc0);
|
|
acc1 = __SMLAD(x1, c0, acc1);
|
|
acc2 = __SMLAD(x3, c0, acc2);
|
|
acc3 = __SMLAD(x2, c0, acc3);
|
|
}
|
|
|
|
if(k == 3u)
|
|
{
|
|
/* Read y[4], y[5] */
|
|
a = *py;
|
|
b = *(py + 1);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
c0 = __PKHBT(a, b, 16);
|
|
|
|
#else
|
|
|
|
c0 = __PKHBT(b, a, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
py += 2u;
|
|
|
|
/* Read x[7], x[8], x[9] */
|
|
a = *px;
|
|
b = *(px + 1);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
x3 = __PKHBT(a, b, 16);
|
|
a = *(px + 2);
|
|
x2 = __PKHBT(b, a, 16);
|
|
|
|
#else
|
|
|
|
x3 = __PKHBT(b, a, 16);
|
|
a = *(px + 2);
|
|
x2 = __PKHBT(a, b, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
/* Perform the multiply-accumulates */
|
|
acc0 = __SMLAD(x0, c0, acc0);
|
|
acc1 = __SMLAD(x1, c0, acc1);
|
|
acc2 = __SMLAD(x3, c0, acc2);
|
|
acc3 = __SMLAD(x2, c0, acc3);
|
|
|
|
c0 = (*py);
|
|
/* Read y[6] */
|
|
#ifdef ARM_MATH_BIG_ENDIAN
|
|
|
|
c0 = c0 << 16u;
|
|
#else
|
|
|
|
c0 = c0 & 0x0000FFFF;
|
|
#endif /* #ifdef ARM_MATH_BIG_ENDIAN */
|
|
|
|
/* Read x[10] */
|
|
b = *(px + 3);
|
|
|
|
#ifndef ARM_MATH_BIG_ENDIAN
|
|
|
|
x3 = __PKHBT(a, b, 16);
|
|
|
|
#else
|
|
|
|
x3 = __PKHBT(b, a, 16);
|
|
|
|
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
|
|
|
|
px += 3u;
|
|
|
|
/* Perform the multiply-accumulates */
|
|
acc0 = __SMLADX(x1, c0, acc0);
|
|
acc1 = __SMLAD(x2, c0, acc1);
|
|
acc2 = __SMLADX(x2, c0, acc2);
|
|
acc3 = __SMLADX(x3, c0, acc3);
|
|
}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (acc0 >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
*pOut = (q15_t) (acc1 >> 15);
|
|
pOut += inc;
|
|
|
|
*pOut = (q15_t) (acc2 >> 15);
|
|
pOut += inc;
|
|
|
|
*pOut = (q15_t) (acc3 >> 15);
|
|
pOut += inc;
|
|
|
|
/* Increment the pointer pIn1 index, count by 1 */
|
|
count += 4u;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
px = pIn1 + count;
|
|
py = pIn2;
|
|
|
|
|
|
/* Decrement the loop counter */
|
|
blkCnt--;
|
|
}
|
|
|
|
/* If the blockSize2 is not a multiple of 4, compute any remaining output samples here.
|
|
** No loop unrolling is used. */
|
|
blkCnt = blockSize2 % 0x4u;
|
|
|
|
while(blkCnt > 0u)
|
|
{
|
|
/* Accumulator is made zero for every iteration */
|
|
sum = 0;
|
|
|
|
/* Apply loop unrolling and compute 4 MACs simultaneously. */
|
|
k = srcBLen >> 2u;
|
|
|
|
/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
|
|
** a second loop below computes MACs for the remaining 1 to 3 samples. */
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulates */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* If the srcBLen is not a multiple of 4, compute any remaining MACs here.
|
|
** No loop unrolling is used. */
|
|
k = srcBLen % 0x4u;
|
|
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulates */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (sum >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
/* Increment the pointer pIn1 index, count by 1 */
|
|
count++;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
px = pIn1 + count;
|
|
py = pIn2;
|
|
|
|
/* Decrement the loop counter */
|
|
blkCnt--;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* If the srcBLen is not a multiple of 4,
|
|
* the blockSize2 loop cannot be unrolled by 4 */
|
|
blkCnt = blockSize2;
|
|
|
|
while(blkCnt > 0u)
|
|
{
|
|
/* Accumulator is made zero for every iteration */
|
|
sum = 0;
|
|
|
|
/* Loop over srcBLen */
|
|
k = srcBLen;
|
|
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulate */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (sum >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
/* Increment the MAC count */
|
|
count++;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
px = pIn1 + count;
|
|
py = pIn2;
|
|
|
|
/* Decrement the loop counter */
|
|
blkCnt--;
|
|
}
|
|
}
|
|
|
|
/* --------------------------
|
|
* Initializations of stage3
|
|
* -------------------------*/
|
|
|
|
/* sum += x[srcALen-srcBLen+1] * y[0] + x[srcALen-srcBLen+2] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
|
|
* sum += x[srcALen-srcBLen+2] * y[0] + x[srcALen-srcBLen+3] * y[1] +...+ x[srcALen-1] * y[srcBLen-1]
|
|
* ....
|
|
* sum += x[srcALen-2] * y[0] + x[srcALen-1] * y[1]
|
|
* sum += x[srcALen-1] * y[0]
|
|
*/
|
|
|
|
/* In this stage the MAC operations are decreased by 1 for every iteration.
|
|
The count variable holds the number of MAC operations performed */
|
|
count = srcBLen - 1u;
|
|
|
|
/* Working pointer of inputA */
|
|
pSrc1 = (pIn1 + srcALen) - (srcBLen - 1u);
|
|
px = pSrc1;
|
|
|
|
/* Working pointer of inputB */
|
|
py = pIn2;
|
|
|
|
/* -------------------
|
|
* Stage3 process
|
|
* ------------------*/
|
|
|
|
while(blockSize3 > 0u)
|
|
{
|
|
/* Accumulator is made zero for every iteration */
|
|
sum = 0;
|
|
|
|
/* Apply loop unrolling and compute 4 MACs simultaneously. */
|
|
k = count >> 2u;
|
|
|
|
/* First part of the processing with loop unrolling. Compute 4 MACs at a time.
|
|
** a second loop below computes MACs for the remaining 1 to 3 samples. */
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulates */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* If the count is not a multiple of 4, compute any remaining MACs here.
|
|
** No loop unrolling is used. */
|
|
k = count % 0x4u;
|
|
|
|
while(k > 0u)
|
|
{
|
|
/* Perform the multiply-accumulates */
|
|
sum += ((q31_t) * px++ * *py++);
|
|
|
|
/* Decrement the loop counter */
|
|
k--;
|
|
}
|
|
|
|
/* Store the result in the accumulator in the destination buffer. */
|
|
*pOut = (q15_t) (sum >> 15);
|
|
/* Destination pointer is updated according to the address modifier, inc */
|
|
pOut += inc;
|
|
|
|
/* Update the inputA and inputB pointers for next MAC calculation */
|
|
px = ++pSrc1;
|
|
py = pIn2;
|
|
|
|
/* Decrement the MAC count */
|
|
count--;
|
|
|
|
/* Decrement the loop counter */
|
|
blockSize3--;
|
|
}
|
|
|
|
#endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */
|
|
|
|
}
|
|
|
|
/**
|
|
* @} end of Corr group
|
|
*/
|