/* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date: 15. February 2012
* $Revision: V1.1.0
*
* Project: CMSIS DSP Library
* Title: arm_conv_partial_fast_opt_q15.c
*
* Description: Fast Q15 Partial convolution.
*
* Target Processor: Cortex-M4/Cortex-M3
*
* Version 1.1.0 2012/02/15
* Updated with more optimizations, bug fixes and minor API changes.
*
* Version 1.0.11 2011/10/18
* Bug Fix in conv, correlation, partial convolution.
*
* Version 1.0.10 2011/7/15
* Big Endian support added and Merged M0 and M3/M4 Source code.
*
* Version 1.0.3 2010/11/29
* Re-organized the CMSIS folders and updated documentation.
*
* Version 1.0.2 2010/11/11
* Documentation updated.
*
* Version 1.0.1 2010/10/05
* Production release and review comments incorporated.
*
* Version 1.0.0 2010/09/20
* Production release and review comments incorporated.
* -------------------------------------------------------------------- */
#include "arm_math.h"
/**
* @ingroup groupFilters
*/
/**
* @addtogroup PartialConv
* @{
*/
/**
* @brief Partial convolution of Q15 sequences (fast version) for Cortex-M3 and Cortex-M4.
* @param[in] *pSrcA points to the first input sequence.
* @param[in] srcALen length of the first input sequence.
* @param[in] *pSrcB points to the second input sequence.
* @param[in] srcBLen length of the second input sequence.
* @param[out] *pDst points to the location where the output result is written.
* @param[in] firstIndex is the first output sample to start with.
* @param[in] numPoints is the number of output points to be computed.
* @param[in] *pScratch1 points to scratch buffer of size max(srcALen, srcBLen) + 2*min(srcALen, srcBLen) - 2.
* @param[in] *pScratch2 points to scratch buffer of size min(srcALen, srcBLen).
* @return Returns either ARM_MATH_SUCCESS if the function completed correctly or ARM_MATH_ARGUMENT_ERROR if the requested subset is not in the range [0 srcALen+srcBLen-2].
*
* See <code>arm_conv_partial_q15()</code> for a slower implementation of this function which uses a 64-bit accumulator to avoid wrap around distortion.
*
* \par Restrictions
* If the silicon does not support unaligned memory access enable the macro UNALIGNED_SUPPORT_DISABLE
* In this case input, output, scratch1 and scratch2 buffers should be aligned by 32-bit
*
*/
#ifndef UNALIGNED_SUPPORT_DISABLE
arm_status arm_conv_partial_fast_opt_q15(
q15_t * pSrcA,
uint32_t srcALen,
q15_t * pSrcB,
uint32_t srcBLen,
q15_t * pDst,
uint32_t firstIndex,
uint32_t numPoints,
q15_t * pScratch1,
q15_t * pScratch2)
{
q15_t *pOut = pDst; /* output pointer */
q15_t *pScr1 = pScratch1; /* Temporary pointer for scratch1 */
q15_t *pScr2 = pScratch2; /* Temporary pointer for scratch1 */
q31_t acc0, acc1, acc2, acc3; /* Accumulator */
q31_t x1, x2, x3; /* Temporary variables to hold state and coefficient values */
q31_t y1, y2; /* State variables */
q15_t *pIn1; /* inputA pointer */
q15_t *pIn2; /* inputB pointer */
q15_t *px; /* Intermediate inputA pointer */
q15_t *py; /* Intermediate inputB pointer */
uint32_t j, k, blkCnt; /* loop counter */
arm_status status;
uint32_t tapCnt; /* loop count */
/* Check for range of output samples to be calculated */
if((firstIndex + numPoints) > ((srcALen + (srcBLen - 1u))))
{
/* Set status as ARM_MATH_ARGUMENT_ERROR */
status = ARM_MATH_ARGUMENT_ERROR;
}
else
{
/* 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 */
if(srcALen >= srcBLen)
{
/* Initialization of inputA pointer */
pIn1 = pSrcA;
/* Initialization of inputB pointer */
pIn2 = pSrcB;
}
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;
}
/* Temporary pointer for scratch2 */
py = pScratch2;
/* pointer to take end of scratch2 buffer */
pScr2 = pScratch2 + srcBLen - 1;
/* points to smaller length sequence */
px = pIn2;
/* Apply loop unrolling and do 4 Copies simultaneously. */
k = srcBLen >> 2u;
/* First part of the processing with loop unrolling copies 4 data points at a time.
** a second loop below copies for the remaining 1 to 3 samples. */
/* Copy smaller length input sequence in reverse order into second scratch buffer */
while(k > 0u)
{
/* copy second buffer in reversal manner */
*pScr2-- = *px++;
*pScr2-- = *px++;
*pScr2-- = *px++;
*pScr2-- = *px++;
/* Decrement the loop counter */
k--;
}
/* If the count is not a multiple of 4, copy remaining samples here.
** No loop unrolling is used. */
k = srcBLen % 0x4u;
while(k > 0u)
{
/* copy second buffer in reversal manner for remaining samples */
*pScr2-- = *px++;
/* Decrement the loop counter */
k--;
}
/* Initialze temporary scratch pointer */
pScr1 = pScratch1;
/* Assuming scratch1 buffer is aligned by 32-bit */
/* Fill (srcBLen - 1u) zeros in scratch buffer */
arm_fill_q15(0, pScr1, (srcBLen - 1u));
/* Update temporary scratch pointer */
pScr1 += (srcBLen - 1u);
/* Copy bigger length sequence(srcALen) samples in scratch1 buffer */
/* Copy (srcALen) samples in scratch buffer */
arm_copy_q15(pIn1, pScr1, srcALen);
/* Update pointers */
pScr1 += srcALen;
/* Fill (srcBLen - 1u) zeros at end of scratch buffer */
arm_fill_q15(0, pScr1, (srcBLen - 1u));
/* Update pointer */
pScr1 += (srcBLen - 1u);
/* Initialization of pIn2 pointer */
pIn2 = py;
pScratch1 += firstIndex;
pOut = pDst + firstIndex;
/* First part of the processing with loop unrolling process 4 data points at a time.
** a second loop below process for the remaining 1 to 3 samples. */
/* Actual convolution process starts here */
blkCnt = (numPoints) >> 2;
while(blkCnt > 0)
{
/* Initialze temporary scratch pointer as scratch1 */
pScr1 = pScratch1;
/* Clear Accumlators */
acc0 = 0;
acc1 = 0;
acc2 = 0;
acc3 = 0;
/* Read two samples from scratch1 buffer */
x1 = *__SIMD32(pScr1)++;
/* Read next two samples from scratch1 buffer */
x2 = *__SIMD32(pScr1)++;
tapCnt = (srcBLen) >> 2u;
while(tapCnt > 0u)
{
/* Read four samples from smaller buffer */
y1 = _SIMD32_OFFSET(pIn2);
y2 = _SIMD32_OFFSET(pIn2 + 2u);
/* multiply and accumlate */
acc0 = __SMLAD(x1, y1, acc0);
acc2 = __SMLAD(x2, y1, acc2);
/* pack input data */
#ifndef ARM_MATH_BIG_ENDIAN
x3 = __PKHBT(x2, x1, 0);
#else
x3 = __PKHBT(x1, x2, 0);
#endif
/* multiply and accumlate */
acc1 = __SMLADX(x3, y1, acc1);
/* Read next two samples from scratch1 buffer */
x1 = _SIMD32_OFFSET(pScr1);
/* multiply and accumlate */
acc0 = __SMLAD(x2, y2, acc0);
acc2 = __SMLAD(x1, y2, acc2);
/* pack input data */
#ifndef ARM_MATH_BIG_ENDIAN
x3 = __PKHBT(x1, x2, 0);
#else
x3 = __PKHBT(x2, x1, 0);
#endif
acc3 = __SMLADX(x3, y1, acc3);
acc1 = __SMLADX(x3, y2, acc1);
x2 = _SIMD32_OFFSET(pScr1 + 2u);
#ifndef ARM_MATH_BIG_ENDIAN
x3 = __PKHBT(x2, x1, 0);
#else
x3 = __PKHBT(x1, x2, 0);
#endif
acc3 = __SMLADX(x3, y2, acc3);
/* update scratch pointers */
pIn2 += 4u;
pScr1 += 4u;
/* Decrement the loop counter */
tapCnt--;
}
/* Update scratch pointer for remaining samples of smaller length sequence */
pScr1 -= 4u;
/* apply same above for remaining samples of smaller length sequence */
tapCnt = (srcBLen) & 3u;
while(tapCnt > 0u)
{
/* accumlate the results */
acc0 += (*pScr1++ * *pIn2);
acc1 += (*pScr1++ * *pIn2);
acc2 += (*pScr1++ * *pIn2);
acc3 += (*pScr1++ * *pIn2++);
pScr1 -= 3u;
/* Decrement the loop counter */
tapCnt--;
}
blkCnt--;
/* Store the results in the accumulators in the destination buffer. */
#ifndef ARM_MATH_BIG_ENDIAN
*__SIMD32(pOut)++ =
__PKHBT(__SSAT((acc0 >> 15), 16), __SSAT((acc1 >> 15), 16), 16);
*__SIMD32(pOut)++ =
__PKHBT(__SSAT((acc2 >> 15), 16), __SSAT((acc3 >> 15), 16), 16);
#else
*__SIMD32(pOut)++ =
__PKHBT(__SSAT((acc1 >> 15), 16), __SSAT((acc0 >> 15), 16), 16);
*__SIMD32(pOut)++ =
__PKHBT(__SSAT((acc3 >> 15), 16), __SSAT((acc2 >> 15), 16), 16);
#endif /* #ifndef ARM_MATH_BIG_ENDIAN */
/* Initialization of inputB pointer */
pIn2 = py;
pScratch1 += 4u;
}
blkCnt = numPoints & 0x3;
/* Calculate convolution for remaining samples of Bigger length sequence */
while(blkCnt > 0)
{
/* Initialze temporary scratch pointer as scratch1 */
pScr1 = pScratch1;
/* Clear Accumlators */
acc0 = 0;
tapCnt = (srcBLen) >> 1u;
while(tapCnt > 0u)
{
/* Read next two samples from scratch1 buffer */
x1 = *__SIMD32(pScr1)++;
/* Read two samples from smaller buffer */
y1 = *__SIMD32(pIn2)++;
acc0 = __SMLAD(x1, y1, acc0);
/* Decrement the loop counter */
tapCnt--;
}
tapCnt = (srcBLen) & 1u;
/* apply same above for remaining samples of smaller length sequence */
while(tapCnt > 0u)
{
/* accumlate the results */
acc0 += (*pScr1++ * *pIn2++);
/* Decrement the loop counter */
tapCnt--;
}
blkCnt--;
/* The result is in 2.30 format. Convert to 1.15 with saturation.
** Then store the output in the destination buffer. */
*pOut++ = (q15_t) (__SSAT((acc0 >> 15), 16));
/* Initialization of inputB pointer */
pIn2 = py;
pScratch1 += 1u;
}
/* set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;
}
/* Return to application */
return (status);
}
#else
arm_status arm_conv_partial_fast_opt_q15(
q15_t * pSrcA,
uint32_t srcALen,
q15_t * pSrcB,
uint32_t srcBLen,
q15_t * pDst,
uint32_t firstIndex,
uint32_t numPoints,
q15_t * pScratch1,
q15_t * pScratch2)
{
q15_t *pOut = pDst; /* output pointer */
q15_t *pScr1 = pScratch1; /* Temporary pointer for scratch1 */
q15_t *pScr2 = pScratch2; /* Temporary pointer for scratch1 */
q31_t acc0, acc1, acc2, acc3; /* Accumulator */
q15_t *pIn1; /* inputA pointer */
q15_t *pIn2; /* inputB pointer */
q15_t *px; /* Intermediate inputA pointer */
q15_t *py; /* Intermediate inputB pointer */
uint32_t j, k, blkCnt; /* loop counter */
arm_status status; /* Status variable */
uint32_t tapCnt; /* loop count */
q15_t x10, x11, x20, x21; /* Temporary variables to hold srcA buffer */
q15_t y10, y11; /* Temporary variables to hold srcB buffer */
/* Check for range of output samples to be calculated */
if((firstIndex + numPoints) > ((srcALen + (srcBLen - 1u))))
{
/* Set status as ARM_MATH_ARGUMENT_ERROR */
status = ARM_MATH_ARGUMENT_ERROR;
}
else
{
/* 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 */
if(srcALen >= srcBLen)
{
/* Initialization of inputA pointer */
pIn1 = pSrcA;
/* Initialization of inputB pointer */
pIn2 = pSrcB;
}
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;
}
/* Temporary pointer for scratch2 */
py = pScratch2;
/* pointer to take end of scratch2 buffer */
pScr2 = pScratch2 + srcBLen - 1;
/* points to smaller length sequence */
px = pIn2;
/* Apply loop unrolling and do 4 Copies simultaneously. */
k = srcBLen >> 2u;
/* First part of the processing with loop unrolling copies 4 data points at a time.
** a second loop below copies for the remaining 1 to 3 samples. */
while(k > 0u)
{
/* copy second buffer in reversal manner */
*pScr2-- = *px++;
*pScr2-- = *px++;
*pScr2-- = *px++;
*pScr2-- = *px++;
/* Decrement the loop counter */
k--;
}
/* If the count is not a multiple of 4, copy remaining samples here.
** No loop unrolling is used. */
k = srcBLen % 0x4u;
while(k > 0u)
{
/* copy second buffer in reversal manner for remaining samples */
*pScr2-- = *px++;
/* Decrement the loop counter */
k--;
}
/* Initialze temporary scratch pointer */
pScr1 = pScratch1;
/* Fill (srcBLen - 1u) zeros in scratch buffer */
arm_fill_q15(0, pScr1, (srcBLen - 1u));
/* Update temporary scratch pointer */
pScr1 += (srcBLen - 1u);
/* Copy bigger length sequence(srcALen) samples in scratch1 buffer */
/* Apply loop unrolling and do 4 Copies simultaneously. */
k = srcALen >> 2u;
/* First part of the processing with loop unrolling copies 4 data points at a time.
** a second loop below copies for the remaining 1 to 3 samples. */
while(k > 0u)
{
/* copy second buffer in reversal manner */
*pScr1++ = *pIn1++;
*pScr1++ = *pIn1++;
*pScr1++ = *pIn1++;
*pScr1++ = *pIn1++;
/* Decrement the loop counter */
k--;
}
/* If the count is not a multiple of 4, copy remaining samples here.
** No loop unrolling is used. */
k = srcALen % 0x4u;
while(k > 0u)
{
/* copy second buffer in reversal manner for remaining samples */
*pScr1++ = *pIn1++;
/* Decrement the loop counter */
k--;
}
/* Apply loop unrolling and do 4 Copies simultaneously. */
k = (srcBLen - 1u) >> 2u;
/* First part of the processing with loop unrolling copies 4 data points at a time.
** a second loop below copies for the remaining 1 to 3 samples. */
while(k > 0u)
{
/* copy second buffer in reversal manner */
*pScr1++ = 0;
*pScr1++ = 0;
*pScr1++ = 0;
*pScr1++ = 0;
/* Decrement the loop counter */
k--;
}
/* If the count is not a multiple of 4, copy remaining samples here.
** No loop unrolling is used. */
k = (srcBLen - 1u) % 0x4u;
while(k > 0u)
{
/* copy second buffer in reversal manner for remaining samples */
*pScr1++ = 0;
/* Decrement the loop counter */
k--;
}
/* Initialization of pIn2 pointer */
pIn2 = py;
pScratch1 += firstIndex;
pOut = pDst + firstIndex;
/* Actual convolution process starts here */
blkCnt = (numPoints) >> 2;
while(blkCnt > 0)
{
/* Initialze temporary scratch pointer as scratch1 */
pScr1 = pScratch1;
/* Clear Accumlators */
acc0 = 0;
acc1 = 0;
acc2 = 0;
acc3 = 0;
/* Read two samples from scratch1 buffer */
x10 = *pScr1++;
x11 = *pScr1++;
/* Read next two samples from scratch1 buffer */
x20 = *pScr1++;
x21 = *pScr1++;
tapCnt = (srcBLen) >> 2u;
while(tapCnt > 0u)
{
/* Read two samples from smaller buffer */
y10 = *pIn2;
y11 = *(pIn2 + 1u);
/* multiply and accumlate */
acc0 += (q31_t) x10 *y10;
acc0 += (q31_t) x11 *y11;
acc2 += (q31_t) x20 *y10;
acc2 += (q31_t) x21 *y11;
/* multiply and accumlate */
acc1 += (q31_t) x11 *y10;
acc1 += (q31_t) x20 *y11;
/* Read next two samples from scratch1 buffer */
x10 = *pScr1;
x11 = *(pScr1 + 1u);
/* multiply and accumlate */
acc3 += (q31_t) x21 *y10;
acc3 += (q31_t) x10 *y11;
/* Read next two samples from scratch2 buffer */
y10 = *(pIn2 + 2u);
y11 = *(pIn2 + 3u);
/* multiply and accumlate */
acc0 += (q31_t) x20 *y10;
acc0 += (q31_t) x21 *y11;
acc2 += (q31_t) x10 *y10;
acc2 += (q31_t) x11 *y11;
acc1 += (q31_t) x21 *y10;
acc1 += (q31_t) x10 *y11;
/* Read next two samples from scratch1 buffer */
x20 = *(pScr1 + 2);
x21 = *(pScr1 + 3);
/* multiply and accumlate */
acc3 += (q31_t) x11 *y10;
acc3 += (q31_t) x20 *y11;
/* update scratch pointers */
pIn2 += 4u;
pScr1 += 4u;
/* Decrement the loop counter */
tapCnt--;
}
/* Update scratch pointer for remaining samples of smaller length sequence */
pScr1 -= 4u;
/* apply same above for remaining samples of smaller length sequence */
tapCnt = (srcBLen) & 3u;
while(tapCnt > 0u)
{
/* accumlate the results */
acc0 += (*pScr1++ * *pIn2);
acc1 += (*pScr1++ * *pIn2);
acc2 += (*pScr1++ * *pIn2);
acc3 += (*pScr1++ * *pIn2++);
pScr1 -= 3u;
/* Decrement the loop counter */
tapCnt--;
}
blkCnt--;
/* Store the results in the accumulators in the destination buffer. */
*pOut++ = __SSAT((acc0 >> 15), 16);
*pOut++ = __SSAT((acc1 >> 15), 16);
*pOut++ = __SSAT((acc2 >> 15), 16);
*pOut++ = __SSAT((acc3 >> 15), 16);
/* Initialization of inputB pointer */
pIn2 = py;
pScratch1 += 4u;
}
blkCnt = numPoints & 0x3;
/* Calculate convolution for remaining samples of Bigger length sequence */
while(blkCnt > 0)
{
/* Initialze temporary scratch pointer as scratch1 */
pScr1 = pScratch1;
/* Clear Accumlators */
acc0 = 0;
tapCnt = (srcBLen) >> 1u;
while(tapCnt > 0u)
{
/* Read next two samples from scratch1 buffer */
x10 = *pScr1++;
x11 = *pScr1++;
/* Read two samples from smaller buffer */
y10 = *pIn2++;
y11 = *pIn2++;
/* multiply and accumlate */
acc0 += (q31_t) x10 *y10;
acc0 += (q31_t) x11 *y11;
/* Decrement the loop counter */
tapCnt--;
}
tapCnt = (srcBLen) & 1u;
/* apply same above for remaining samples of smaller length sequence */
while(tapCnt > 0u)
{
/* accumlate the results */
acc0 += (*pScr1++ * *pIn2++);
/* Decrement the loop counter */
tapCnt--;
}
blkCnt--;
/* Store the result in the accumulator in the destination buffer. */
*pOut++ = (q15_t) (__SSAT((acc0 >> 15), 16));
/* Initialization of inputB pointer */
pIn2 = py;
pScratch1 += 1u;
}
/* set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;
}
/* Return to application */
return (status);
}
#endif /* #ifndef UNALIGNED_SUPPORT_DISABLE */
/**
* @} end of PartialConv group
*/