/* ----------------------------------------------------------------------
* Project: CMSIS DSP Library
* Title: arm_cmplx_mag_q15.c
* Description: Q15 complex magnitude
*
* $Date: 23 April 2021
* $Revision: V1.9.0
*
* Target Processor: Cortex-M and Cortex-A cores
* -------------------------------------------------------------------- */
/*
* Copyright (C) 2010-2021 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 "dsp/complex_math_functions.h"
/**
@ingroup groupCmplxMath
*/
/**
@addtogroup cmplx_mag
@{
*/
/**
@brief Q15 complex magnitude.
@param[in] pSrc points to input vector
@param[out] pDst points to output vector
@param[in] numSamples number of samples in each vector
@return none
@par Scaling and Overflow Behavior
The function implements 1.15 by 1.15 multiplications and finally output is converted into 2.14 format.
*/
/* Sqrt q31 is used otherwise accuracy is not good enough
for small values and for some applications it is
an issue.
*/
#if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE)
#include "arm_helium_utils.h"
void arm_cmplx_mag_q15(
const q15_t * pSrc,
q15_t * pDst,
uint32_t numSamples)
{
int32_t blockSize = numSamples; /* loop counters */
uint32_t blkCnt; /* loop counters */
q15x8x2_t vecSrc;
q31x4_t prod0;
q31x4_t prod1;
q31_t in;
q31_t acc0;
q31x4_t acc0V;
q31x4_t acc1V;
q31_t res;
q15x8_t resV;
blkCnt = blockSize >> 3;
while (blkCnt > 0U)
{
vecSrc = vld2q(pSrc);
pSrc += 16;
acc0V = vdupq_n_s32(0);
acc1V = vdupq_n_s32(0);
prod0 = vmullbq_int_s16(vecSrc.val[0], vecSrc.val[0]);
acc0V = vqaddq_s32(acc0V,prod0);
prod0 = vmullbq_int_s16(vecSrc.val[1], vecSrc.val[1]);
acc0V = vqaddq_s32(acc0V,prod0);
prod1 = vmulltq_int_s16(vecSrc.val[0], vecSrc.val[0]);
acc1V = vqaddq_s32(acc1V,prod1);
prod1 = vmulltq_int_s16(vecSrc.val[1], vecSrc.val[1]);
acc1V = vqaddq_s32(acc1V,prod1);
acc0V = vshrq(acc0V, 1);
acc1V = vshrq(acc1V, 1);
acc0V = FAST_VSQRT_Q31(acc0V);
acc1V = FAST_VSQRT_Q31(acc1V);
resV = vdupq_n_s16(0);
resV = vqshrnbq_n_s32(resV,acc0V,16);
resV = vqshrntq_n_s32(resV,acc1V,16);
vst1q(pDst, resV);
pDst += 8;
/*
* Decrement the blockSize loop counter
*/
blkCnt--;
}
/*
* tail
*/
blkCnt = blockSize & 7;
while (blkCnt > 0U)
{
/* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
in = read_q15x2_ia ((q15_t **) &pSrc);
acc0 = __SMUAD(in, in);
/* store result in 2.14 format in destination buffer. */
arm_sqrt_q31(acc0 >> 1 , &res);
*pDst++ = res >> 16;
/* Decrement loop counter */
blkCnt--;
}
}
#else
void arm_cmplx_mag_q15(
const q15_t * pSrc,
q15_t * pDst,
uint32_t numSamples)
{
q31_t res; /* temporary result */
uint32_t blkCnt; /* Loop counter */
#if defined (ARM_MATH_DSP)
q31_t in;
q31_t acc0; /* Accumulators */
#else
q15_t real, imag; /* Temporary input variables */
q31_t acc0, acc1; /* Accumulators */
#endif
#if defined (ARM_MATH_LOOPUNROLL)
/* Loop unrolling: Compute 4 outputs at a time */
blkCnt = numSamples >> 2U;
while (blkCnt > 0U)
{
/* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
#if defined (ARM_MATH_DSP)
in = read_q15x2_ia (&pSrc);
acc0 = __SMUAD(in, in);
/* store result in 2.14 format in destination buffer. */
arm_sqrt_q31(acc0 >> 1 , &res);
*pDst++ = res >> 16;
in = read_q15x2_ia (&pSrc);
acc0 = __SMUAD(in, in);
arm_sqrt_q31(acc0 >> 1 , &res);
*pDst++ = res >> 16;
in = read_q15x2_ia (&pSrc);
acc0 = __SMUAD(in, in);
arm_sqrt_q31(acc0 >> 1 , &res);
*pDst++ = res >> 16;
in = read_q15x2_ia (&pSrc);
acc0 = __SMUAD(in, in);
arm_sqrt_q31(acc0 >> 1 , &res);
*pDst++ = res >> 16;
#else
real = *pSrc++;
imag = *pSrc++;
acc0 = ((q31_t) real * real);
acc1 = ((q31_t) imag * imag);
/* store result in 2.14 format in destination buffer. */
arm_sqrt_q31((acc0 + acc1) >> 1 , &res);
*pDst++ = res >> 16;
real = *pSrc++;
imag = *pSrc++;
acc0 = ((q31_t) real * real);
acc1 = ((q31_t) imag * imag);
arm_sqrt_q31((acc0 + acc1) >> 1 , &res);
*pDst++ = res >> 16;
real = *pSrc++;
imag = *pSrc++;
acc0 = ((q31_t) real * real);
acc1 = ((q31_t) imag * imag);
arm_sqrt_q31((acc0 + acc1) >> 1 , &res);
*pDst++ = res >> 16;
real = *pSrc++;
imag = *pSrc++;
acc0 = ((q31_t) real * real);
acc1 = ((q31_t) imag * imag);
arm_sqrt_q31((acc0 + acc1) >> 1 , &res);
*pDst++ = res >> 16;
#endif /* #if defined (ARM_MATH_DSP) */
/* 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)
{
/* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
#if defined (ARM_MATH_DSP)
in = read_q15x2_ia (&pSrc);
acc0 = __SMUAD(in, in);
/* store result in 2.14 format in destination buffer. */
arm_sqrt_q31(acc0 >> 1 , &res);
*pDst++ = res >> 16;
#else
real = *pSrc++;
imag = *pSrc++;
acc0 = ((q31_t) real * real);
acc1 = ((q31_t) imag * imag);
/* store result in 2.14 format in destination buffer. */
arm_sqrt_q31((acc0 + acc1) >> 1 , &res);
*pDst++ = res >> 16;
#endif
/* Decrement loop counter */
blkCnt--;
}
}
#endif /* defined(ARM_MATH_MVEI) */
/**
@} end of cmplx_mag group
*/