155 lines
4.2 KiB
C
155 lines
4.2 KiB
C
/* ----------------------------------------------------------------------
|
|
* Project: CMSIS DSP Library
|
|
* Title: arm_cmplx_dot_prod_q15.c
|
|
* Description: Processing function for the Q15 Complex Dot product
|
|
*
|
|
* $Date: 18. March 2019
|
|
* $Revision: V1.6.0
|
|
*
|
|
* Target Processor: Cortex-M cores
|
|
* -------------------------------------------------------------------- */
|
|
/*
|
|
* Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the License); you may
|
|
* not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an AS IS BASIS, WITHOUT
|
|
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#include "arm_math.h"
|
|
|
|
/**
|
|
@ingroup groupCmplxMath
|
|
*/
|
|
|
|
/**
|
|
@addtogroup cmplx_dot_prod
|
|
@{
|
|
*/
|
|
|
|
/**
|
|
@brief Q15 complex dot product.
|
|
@param[in] pSrcA points to the first input vector
|
|
@param[in] pSrcB points to the second input vector
|
|
@param[in] numSamples number of samples in each vector
|
|
@param[out] realResult real part of the result returned here
|
|
@param[out] imagResult imaginary part of the result returned her
|
|
@return none
|
|
|
|
@par Scaling and Overflow Behavior
|
|
The function is implemented using an internal 64-bit accumulator.
|
|
The intermediate 1.15 by 1.15 multiplications are performed with full precision and yield a 2.30 result.
|
|
These are accumulated in a 64-bit accumulator with 34.30 precision.
|
|
As a final step, the accumulators are converted to 8.24 format.
|
|
The return results <code>realResult</code> and <code>imagResult</code> are in 8.24 format.
|
|
*/
|
|
|
|
void arm_cmplx_dot_prod_q15(
|
|
const q15_t * pSrcA,
|
|
const q15_t * pSrcB,
|
|
uint32_t numSamples,
|
|
q31_t * realResult,
|
|
q31_t * imagResult)
|
|
{
|
|
uint32_t blkCnt; /* Loop counter */
|
|
q63_t real_sum = 0, imag_sum = 0; /* Temporary result variables */
|
|
q15_t a0,b0,c0,d0;
|
|
|
|
#if defined (ARM_MATH_LOOPUNROLL)
|
|
|
|
/* Loop unrolling: Compute 4 outputs at a time */
|
|
blkCnt = numSamples >> 2U;
|
|
|
|
while (blkCnt > 0U)
|
|
{
|
|
a0 = *pSrcA++;
|
|
b0 = *pSrcA++;
|
|
c0 = *pSrcB++;
|
|
d0 = *pSrcB++;
|
|
|
|
real_sum += (q31_t)a0 * c0;
|
|
imag_sum += (q31_t)a0 * d0;
|
|
real_sum -= (q31_t)b0 * d0;
|
|
imag_sum += (q31_t)b0 * c0;
|
|
|
|
a0 = *pSrcA++;
|
|
b0 = *pSrcA++;
|
|
c0 = *pSrcB++;
|
|
d0 = *pSrcB++;
|
|
|
|
real_sum += (q31_t)a0 * c0;
|
|
imag_sum += (q31_t)a0 * d0;
|
|
real_sum -= (q31_t)b0 * d0;
|
|
imag_sum += (q31_t)b0 * c0;
|
|
|
|
a0 = *pSrcA++;
|
|
b0 = *pSrcA++;
|
|
c0 = *pSrcB++;
|
|
d0 = *pSrcB++;
|
|
|
|
real_sum += (q31_t)a0 * c0;
|
|
imag_sum += (q31_t)a0 * d0;
|
|
real_sum -= (q31_t)b0 * d0;
|
|
imag_sum += (q31_t)b0 * c0;
|
|
|
|
a0 = *pSrcA++;
|
|
b0 = *pSrcA++;
|
|
c0 = *pSrcB++;
|
|
d0 = *pSrcB++;
|
|
|
|
real_sum += (q31_t)a0 * c0;
|
|
imag_sum += (q31_t)a0 * d0;
|
|
real_sum -= (q31_t)b0 * d0;
|
|
imag_sum += (q31_t)b0 * c0;
|
|
|
|
/* Decrement loop counter */
|
|
blkCnt--;
|
|
}
|
|
|
|
/* Loop unrolling: Compute remaining outputs */
|
|
blkCnt = numSamples % 0x4U;
|
|
|
|
#else
|
|
|
|
/* Initialize blkCnt with number of samples */
|
|
blkCnt = numSamples;
|
|
|
|
#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
|
|
|
|
while (blkCnt > 0U)
|
|
{
|
|
a0 = *pSrcA++;
|
|
b0 = *pSrcA++;
|
|
c0 = *pSrcB++;
|
|
d0 = *pSrcB++;
|
|
|
|
real_sum += (q31_t)a0 * c0;
|
|
imag_sum += (q31_t)a0 * d0;
|
|
real_sum -= (q31_t)b0 * d0;
|
|
imag_sum += (q31_t)b0 * c0;
|
|
|
|
/* Decrement loop counter */
|
|
blkCnt--;
|
|
}
|
|
|
|
/* Store real and imaginary result in 8.24 format */
|
|
/* Convert real data in 34.30 to 8.24 by 6 right shifts */
|
|
*realResult = (q31_t) (real_sum >> 6);
|
|
/* Convert imaginary data in 34.30 to 8.24 by 6 right shifts */
|
|
*imagResult = (q31_t) (imag_sum >> 6);
|
|
}
|
|
|
|
/**
|
|
@} end of cmplx_dot_prod group
|
|
*/
|