arm_cmplx_dot_prod_q31.c
142 lines
| 4.7 KiB
| text/x-c
|
CLexer
jeandet@pc-de-jeandet3.LAB-LPP.LOCAL
|
r41 | /* ---------------------------------------------------------------------- | ||
* Copyright (C) 2010 ARM Limited. All rights reserved. | ||||
* | ||||
* $Date: 15. July 2011 | ||||
* $Revision: V1.0.10 | ||||
* | ||||
* Project: CMSIS DSP Library | ||||
* Title: arm_cmplx_dot_prod_q31.c | ||||
* | ||||
* Description: Q31 complex dot product | ||||
* | ||||
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 | ||||
* | ||||
* 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 groupCmplxMath | ||||
*/ | ||||
/** | ||||
* @addtogroup cmplx_dot_prod | ||||
* @{ | ||||
*/ | ||||
/** | ||||
* @brief Q31 complex dot product | ||||
* @param *pSrcA points to the first input vector | ||||
* @param *pSrcB points to the second input vector | ||||
* @param numSamples number of complex samples in each vector | ||||
* @param *realResult real part of the result returned here | ||||
* @param *imagResult imaginary part of the result returned here | ||||
* @return none. | ||||
* | ||||
* <b>Scaling and Overflow Behavior:</b> | ||||
* \par | ||||
* The function is implemented using an internal 64-bit accumulator. | ||||
* The intermediate 1.31 by 1.31 multiplications are performed with 64-bit precision and then shifted to 16.48 format. | ||||
* The internal real and imaginary accumulators are in 16.48 format and provide 15 guard bits. | ||||
* Additions are nonsaturating and no overflow will occur as long as <code>numSamples</code> is less than 32768. | ||||
* The return results <code>realResult</code> and <code>imagResult</code> are in 16.48 format. | ||||
* Input down scaling is not required. | ||||
*/ | ||||
void arm_cmplx_dot_prod_q31( | ||||
q31_t * pSrcA, | ||||
q31_t * pSrcB, | ||||
uint32_t numSamples, | ||||
q63_t * realResult, | ||||
q63_t * imagResult) | ||||
{ | ||||
q63_t real_sum = 0, imag_sum = 0; /* Temporary result storage */ | ||||
#ifndef ARM_MATH_CM0 | ||||
/* Run the below code for Cortex-M4 and Cortex-M3 */ | ||||
uint32_t blkCnt; /* loop counter */ | ||||
/*loop Unrolling */ | ||||
blkCnt = numSamples >> 2u; | ||||
/* First part of the processing with loop unrolling. Compute 4 outputs at a time. | ||||
** a second loop below computes the remaining 1 to 3 samples. */ | ||||
while(blkCnt > 0u) | ||||
{ | ||||
/* CReal = A[0]* B[0] + A[2]* B[2] + A[4]* B[4] + .....+ A[numSamples-2]* B[numSamples-2] */ | ||||
/* Convert real data in 2.62 to 16.48 by 14 right shifts */ | ||||
real_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
/* CImag = A[1]* B[1] + A[3]* B[3] + A[5]* B[5] + .....+ A[numSamples-1]* B[numSamples-1] */ | ||||
/* Convert imag data in 2.62 to 16.48 by 14 right shifts */ | ||||
imag_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
real_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
imag_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
real_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
imag_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
real_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
imag_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
/* Decrement the loop counter */ | ||||
blkCnt--; | ||||
} | ||||
/* If the numSamples is not a multiple of 4, compute any remaining output samples here. | ||||
** No loop unrolling is used. */ | ||||
blkCnt = numSamples % 0x4u; | ||||
while(blkCnt > 0u) | ||||
{ | ||||
/* CReal = A[0]* B[0] + A[2]* B[2] + A[4]* B[4] + .....+ A[numSamples-2]* B[numSamples-2] */ | ||||
real_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
/* CImag = A[1]* B[1] + A[3]* B[3] + A[5]* B[5] + .....+ A[numSamples-1]* B[numSamples-1] */ | ||||
imag_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
/* Decrement the loop counter */ | ||||
blkCnt--; | ||||
} | ||||
#else | ||||
/* Run the below code for Cortex-M0 */ | ||||
while(numSamples > 0u) | ||||
{ | ||||
/* outReal = realA[0]* realB[0] + realA[2]* realB[2] + realA[4]* realB[4] + .....+ realA[numSamples-2]* realB[numSamples-2] */ | ||||
real_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
/* outImag = imagA[1]* imagB[1] + imagA[3]* imagB[3] + imagA[5]* imagB[5] + .....+ imagA[numSamples-1]* imagB[numSamples-1] */ | ||||
imag_sum += (q63_t) * pSrcA++ * (*pSrcB++) >> 14; | ||||
/* Decrement the loop counter */ | ||||
numSamples--; | ||||
} | ||||
#endif /* #ifndef ARM_MATH_CM0 */ | ||||
/* Store the real and imaginary results in 16.48 format */ | ||||
*realResult = real_sum; | ||||
*imagResult = imag_sum; | ||||
} | ||||
/** | ||||
* @} end of cmplx_dot_prod group | ||||
*/ | ||||