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Diff: cmsis_dsp/BasicMathFunctions/arm_dot_prod_q15.c
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diff -r 83d0537c7d84 -r fdd22bb7aa52 cmsis_dsp/BasicMathFunctions/arm_dot_prod_q15.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/BasicMathFunctions/arm_dot_prod_q15.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,135 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_dot_prod_q15.c +* +* Description: Q15 dot product. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* 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. +* +* Version 0.0.7 2010/06/10 +* Misra-C changes done +* -------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupMath + */ + +/** + * @addtogroup dot_prod + * @{ + */ + +/** + * @brief Dot product of Q15 vectors. + * @param[in] *pSrcA points to the first input vector + * @param[in] *pSrcB points to the second input vector + * @param[in] blockSize number of samples in each vector + * @param[out] *result output result returned here + * @return none. + * + * <b>Scaling and Overflow Behavior:</b> + * \par + * The intermediate multiplications are in 1.15 x 1.15 = 2.30 format and these + * results are added to a 64-bit accumulator in 34.30 format. + * Nonsaturating additions are used and given that there are 33 guard bits in the accumulator + * there is no risk of overflow. + * The return result is in 34.30 format. + */ + +void arm_dot_prod_q15( + q15_t * pSrcA, + q15_t * pSrcB, + uint32_t blockSize, + q63_t * result) +{ + q63_t sum = 0; /* Temporary result storage */ + uint32_t blkCnt; /* loop counter */ + +#ifndef ARM_MATH_CM0 + +/* Run the below code for Cortex-M4 and Cortex-M3 */ + + + /*loop Unrolling */ + blkCnt = blockSize >> 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) + { + /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */ + /* Calculate dot product and then store the result in a temporary buffer. */ + sum = __SMLALD(*__SIMD32(pSrcA)++, *__SIMD32(pSrcB)++, sum); + sum = __SMLALD(*__SIMD32(pSrcA)++, *__SIMD32(pSrcB)++, sum); + + /* Decrement the loop counter */ + blkCnt--; + } + + /* If the blockSize is not a multiple of 4, compute any remaining output samples here. + ** No loop unrolling is used. */ + blkCnt = blockSize % 0x4u; + + while(blkCnt > 0u) + { + /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */ + /* Calculate dot product and then store the results in a temporary buffer. */ + sum = __SMLALD(*pSrcA++, *pSrcB++, sum); + + /* Decrement the loop counter */ + blkCnt--; + } + + +#else + + /* Run the below code for Cortex-M0 */ + + /* Initialize blkCnt with number of samples */ + blkCnt = blockSize; + + while(blkCnt > 0u) + { + /* C = A[0]* B[0] + A[1]* B[1] + A[2]* B[2] + .....+ A[blockSize-1]* B[blockSize-1] */ + /* Calculate dot product and then store the results in a temporary buffer. */ + sum += (q63_t) ((q31_t) * pSrcA++ * *pSrcB++); + + /* Decrement the loop counter */ + blkCnt--; + } + +#endif /* #ifndef ARM_MATH_CM0 */ + + /* Store the result in the destination buffer in 34.30 format */ + *result = sum; + +} + +/** + * @} end of dot_prod group + */