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Diffstat (limited to 'DSP_Lib/Source/BasicMathFunctions/arm_dot_prod_q31.c')
-rw-r--r-- | DSP_Lib/Source/BasicMathFunctions/arm_dot_prod_q31.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/DSP_Lib/Source/BasicMathFunctions/arm_dot_prod_q31.c b/DSP_Lib/Source/BasicMathFunctions/arm_dot_prod_q31.c new file mode 100644 index 0000000..b199f8b --- /dev/null +++ b/DSP_Lib/Source/BasicMathFunctions/arm_dot_prod_q31.c @@ -0,0 +1,143 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010-2014 ARM Limited. All rights reserved. +* +* $Date: 19. March 2015 +* $Revision: V.1.4.5 +* +* Project: CMSIS DSP Library +* Title: arm_dot_prod_q31.c +* +* Description: Q31 dot product. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Redistribution and use in source and binary forms, with or without +* modification, are permitted provided that the following conditions +* are met: +* - Redistributions of source code must retain the above copyright +* notice, this list of conditions and the following disclaimer. +* - Redistributions in binary form must reproduce the above copyright +* notice, this list of conditions and the following disclaimer in +* the documentation and/or other materials provided with the +* distribution. +* - Neither the name of ARM LIMITED nor the names of its contributors +* may be used to endorse or promote products derived from this +* software without specific prior written permission. +* +* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS +* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE +* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, +* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, +* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; +* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN +* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +* POSSIBILITY OF SUCH DAMAGE. +* -------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupMath + */ + +/** + * @addtogroup dot_prod + * @{ + */ + +/** + * @brief Dot product of Q31 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 1.31 x 1.31 = 2.62 format and these + * are truncated to 2.48 format by discarding the lower 14 bits. + * The 2.48 result is then added without saturation to a 64-bit accumulator in 16.48 format. + * There are 15 guard bits in the accumulator and there is no risk of overflow as long as + * the length of the vectors is less than 2^16 elements. + * The return result is in 16.48 format. + */ + +void arm_dot_prod_q31( + q31_t * pSrcA, + q31_t * pSrcB, + uint32_t blockSize, + q63_t * result) +{ + q63_t sum = 0; /* Temporary result storage */ + uint32_t blkCnt; /* loop counter */ + + +#ifndef ARM_MATH_CM0_FAMILY + +/* Run the below code for Cortex-M4 and Cortex-M3 */ + q31_t inA1, inA2, inA3, inA4; + q31_t inB1, inB2, inB3, inB4; + + /*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. */ + inA1 = *pSrcA++; + inA2 = *pSrcA++; + inA3 = *pSrcA++; + inA4 = *pSrcA++; + inB1 = *pSrcB++; + inB2 = *pSrcB++; + inB3 = *pSrcB++; + inB4 = *pSrcB++; + + sum += ((q63_t) inA1 * inB1) >> 14u; + sum += ((q63_t) inA2 * inB2) >> 14u; + sum += ((q63_t) inA3 * inB3) >> 14u; + sum += ((q63_t) inA4 * inB4) >> 14u; + + /* 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; + +#else + + /* Run the below code for Cortex-M0 */ + + /* Initialize blkCnt with number of samples */ + blkCnt = blockSize; + +#endif /* #ifndef ARM_MATH_CM0_FAMILY */ + + + 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 += ((q63_t) * pSrcA++ * *pSrcB++) >> 14u; + + /* Decrement the loop counter */ + blkCnt--; + } + + /* Store the result in the destination buffer in 16.48 format */ + *result = sum; +} + +/** + * @} end of dot_prod group + */ |