/* ----------------------------------------------------------------------
|
* Project: CMSIS DSP Library
|
* Title: arm_cmplx_mult_real_q31.c
|
* Description: Q31 complex by real multiplication
|
*
|
* $Date: 27. January 2017
|
* $Revision: V.1.5.1
|
*
|
* Target Processor: Cortex-M cores
|
* -------------------------------------------------------------------- */
|
/*
|
* Copyright (C) 2010-2017 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 CmplxByRealMult
|
* @{
|
*/
|
|
|
/**
|
* @brief Q31 complex-by-real multiplication
|
* @param[in] *pSrcCmplx points to the complex input vector
|
* @param[in] *pSrcReal points to the real input vector
|
* @param[out] *pCmplxDst points to the complex output vector
|
* @param[in] numSamples number of samples in each vector
|
* @return none.
|
*
|
* <b>Scaling and Overflow Behavior:</b>
|
* \par
|
* The function uses saturating arithmetic.
|
* Results outside of the allowable Q31 range[0x80000000 0x7FFFFFFF] will be saturated.
|
*/
|
|
void arm_cmplx_mult_real_q31(
|
q31_t * pSrcCmplx,
|
q31_t * pSrcReal,
|
q31_t * pCmplxDst,
|
uint32_t numSamples)
|
{
|
q31_t inA1; /* Temporary variable to store input value */
|
|
#if defined (ARM_MATH_DSP)
|
|
/* Run the below code for Cortex-M4 and Cortex-M3 */
|
uint32_t blkCnt; /* loop counters */
|
q31_t inA2, inA3, inA4; /* Temporary variables to hold input data */
|
q31_t inB1, inB2; /* Temporary variabels to hold input data */
|
q31_t out1, out2, out3, out4; /* Temporary variables to hold output data */
|
|
/* 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)
|
{
|
/* C[2 * i] = A[2 * i] * B[i]. */
|
/* C[2 * i + 1] = A[2 * i + 1] * B[i]. */
|
/* read real input from complex input buffer */
|
inA1 = *pSrcCmplx++;
|
inA2 = *pSrcCmplx++;
|
/* read input from real input bufer */
|
inB1 = *pSrcReal++;
|
inB2 = *pSrcReal++;
|
/* read imaginary input from complex input buffer */
|
inA3 = *pSrcCmplx++;
|
inA4 = *pSrcCmplx++;
|
|
/* multiply complex input with real input */
|
out1 = ((q63_t) inA1 * inB1) >> 32;
|
out2 = ((q63_t) inA2 * inB1) >> 32;
|
out3 = ((q63_t) inA3 * inB2) >> 32;
|
out4 = ((q63_t) inA4 * inB2) >> 32;
|
|
/* sature the result */
|
out1 = __SSAT(out1, 31);
|
out2 = __SSAT(out2, 31);
|
out3 = __SSAT(out3, 31);
|
out4 = __SSAT(out4, 31);
|
|
/* get result in 1.31 format */
|
out1 = out1 << 1;
|
out2 = out2 << 1;
|
out3 = out3 << 1;
|
out4 = out4 << 1;
|
|
/* store the result to destination buffer */
|
*pCmplxDst++ = out1;
|
*pCmplxDst++ = out2;
|
*pCmplxDst++ = out3;
|
*pCmplxDst++ = out4;
|
|
/* read real input from complex input buffer */
|
inA1 = *pSrcCmplx++;
|
inA2 = *pSrcCmplx++;
|
/* read input from real input bufer */
|
inB1 = *pSrcReal++;
|
inB2 = *pSrcReal++;
|
/* read imaginary input from complex input buffer */
|
inA3 = *pSrcCmplx++;
|
inA4 = *pSrcCmplx++;
|
|
/* multiply complex input with real input */
|
out1 = ((q63_t) inA1 * inB1) >> 32;
|
out2 = ((q63_t) inA2 * inB1) >> 32;
|
out3 = ((q63_t) inA3 * inB2) >> 32;
|
out4 = ((q63_t) inA4 * inB2) >> 32;
|
|
/* sature the result */
|
out1 = __SSAT(out1, 31);
|
out2 = __SSAT(out2, 31);
|
out3 = __SSAT(out3, 31);
|
out4 = __SSAT(out4, 31);
|
|
/* get result in 1.31 format */
|
out1 = out1 << 1;
|
out2 = out2 << 1;
|
out3 = out3 << 1;
|
out4 = out4 << 1;
|
|
/* store the result to destination buffer */
|
*pCmplxDst++ = out1;
|
*pCmplxDst++ = out2;
|
*pCmplxDst++ = out3;
|
*pCmplxDst++ = out4;
|
|
/* Decrement the numSamples 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)
|
{
|
/* C[2 * i] = A[2 * i] * B[i]. */
|
/* C[2 * i + 1] = A[2 * i + 1] * B[i]. */
|
/* read real input from complex input buffer */
|
inA1 = *pSrcCmplx++;
|
inA2 = *pSrcCmplx++;
|
/* read input from real input bufer */
|
inB1 = *pSrcReal++;
|
|
/* multiply complex input with real input */
|
out1 = ((q63_t) inA1 * inB1) >> 32;
|
out2 = ((q63_t) inA2 * inB1) >> 32;
|
|
/* sature the result */
|
out1 = __SSAT(out1, 31);
|
out2 = __SSAT(out2, 31);
|
|
/* get result in 1.31 format */
|
out1 = out1 << 1;
|
out2 = out2 << 1;
|
|
/* store the result to destination buffer */
|
*pCmplxDst++ = out1;
|
*pCmplxDst++ = out2;
|
|
/* Decrement the numSamples loop counter */
|
blkCnt--;
|
}
|
|
#else
|
|
/* Run the below code for Cortex-M0 */
|
|
while (numSamples > 0U)
|
{
|
/* realOut = realA * realB. */
|
/* imagReal = imagA * realB. */
|
inA1 = *pSrcReal++;
|
/* store the result in the destination buffer. */
|
*pCmplxDst++ =
|
(q31_t) clip_q63_to_q31(((q63_t) * pSrcCmplx++ * inA1) >> 31);
|
*pCmplxDst++ =
|
(q31_t) clip_q63_to_q31(((q63_t) * pSrcCmplx++ * inA1) >> 31);
|
|
/* Decrement the numSamples loop counter */
|
numSamples--;
|
}
|
|
#endif /* #if defined (ARM_MATH_DSP) */
|
|
}
|
|
/**
|
* @} end of CmplxByRealMult group
|
*/
|
