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/* ----------------------------------------------------------------------    

* Copyright (C) 2010-2014 ARM Limited. All rights reserved.    

*    

* $Date:        19. March 2015

* $Revision:    V.1.4.5

*    

* Project:          CMSIS DSP Library    

* Title:            arm_cmplx_mult_real_f32.c    

*    

* Description:  Floating-point complex by real multiplication    

*    

* 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

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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

* POSSIBILITY OF SUCH DAMAGE.  

* -------------------------------------------------------------------- */

#include "arm_math.h"

/**        

 * @ingroup groupCmplxMath        

 */

/**        

 * @defgroup CmplxByRealMult Complex-by-Real Multiplication        

 *        

 * Multiplies a complex vector by a real vector and generates a complex result.        

 * The data in the complex arrays is stored in an interleaved fashion        

 * (real, imag, real, imag, ...).        

 * The parameter <code>numSamples</code> represents the number of complex        

 * samples processed.  The complex arrays have a total of <code>2*numSamples</code>        

 * real values while the real array has a total of <code>numSamples</code>        

 * real values.        

 *        

 * The underlying algorithm is used:        

 *        

 * <pre>        

 * for(n=0; n<numSamples; n++) {        

 *     pCmplxDst[(2*n)+0] = pSrcCmplx[(2*n)+0] * pSrcReal[n];        

 *     pCmplxDst[(2*n)+1] = pSrcCmplx[(2*n)+1] * pSrcReal[n];        

 * }        

 * </pre>        

 *        

 * There are separate functions for floating-point, Q15, and Q31 data types.        

 */

/**        

 * @addtogroup CmplxByRealMult        

 * @{        

 */

/**        

 * @brief  Floating-point 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.        

 */

void arm_cmplx_mult_real_f32(

  float32_t * pSrcCmplx,

  float32_t * pSrcReal,

  float32_t * pCmplxDst,

  uint32_t numSamples)

{

  float32_t in;                                  /* Temporary variable to store input value */

  uint32_t blkCnt;                               /* loop counters */

#ifndef ARM_MATH_CM0_FAMILY

  /* Run the below code for Cortex-M4 and Cortex-M3 */

  float32_t inA1, inA2, inA3, inA4;              /* Temporary variables to hold input data */

  float32_t inA5, inA6, inA7, inA8;              /* Temporary variables to hold input data */

  float32_t inB1, inB2, inB3, inB4;              /* Temporary variables to hold input data */

  float32_t out1, out2, out3, out4;              /* Temporary variables to hold output data */

  float32_t out5, out6, out7, out8;              /* 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 input from complex input buffer */

    inA1 = pSrcCmplx[0];

    inA2 = pSrcCmplx[1];

    /* read input from real input buffer */

    inB1 = pSrcReal[0];

    /* read input from complex input buffer */

    inA3 = pSrcCmplx[2];

    /* multiply complex buffer real input with real buffer input */

    out1 = inA1 * inB1;

    /* read input from complex input buffer */

    inA4 = pSrcCmplx[3];

    /* multiply complex buffer imaginary input with real buffer input */

    out2 = inA2 * inB1;

    /* read input from real input buffer */

    inB2 = pSrcReal[1];

    /* read input from complex input buffer */

    inA5 = pSrcCmplx[4];

    /* multiply complex buffer real input with real buffer input */

    out3 = inA3 * inB2;

    /* read input from complex input buffer */

    inA6 = pSrcCmplx[5];

    /* read input from real input buffer */

    inB3 = pSrcReal[2];

    /* multiply complex buffer imaginary input with real buffer input */

    out4 = inA4 * inB2;

    /* read input from complex input buffer */

    inA7 = pSrcCmplx[6];

    /* multiply complex buffer real input with real buffer input */

    out5 = inA5 * inB3;

    /* read input from complex input buffer */

    inA8 = pSrcCmplx[7];

    /* multiply complex buffer imaginary input with real buffer input */

    out6 = inA6 * inB3;

    /* read input from real input buffer */

    inB4 = pSrcReal[3];

    /* store result to destination bufer */

    pCmplxDst[0] = out1;

    /* multiply complex buffer real input with real buffer input */

    out7 = inA7 * inB4;

    /* store result to destination bufer */

    pCmplxDst[1] = out2;

    /* multiply complex buffer imaginary input with real buffer input */

    out8 = inA8 * inB4;

    /* store result to destination bufer */

    pCmplxDst[2] = out3;

    pCmplxDst[3] = out4;

    pCmplxDst[4] = out5;

    /* incremnet complex input buffer by 8 to process next samples */

    pSrcCmplx += 8u;

    /* store result to destination bufer */

    pCmplxDst[5] = out6;

    /* increment real input buffer by 4 to process next samples */

    pSrcReal += 4u;

    /* store result to destination bufer */

    pCmplxDst[6] = out7;

    pCmplxDst[7] = out8;

    /* increment destination buffer by 8 to process next sampels */

    pCmplxDst += 8u;

    /* 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;

#else

  /* Run the below code for Cortex-M0 */

  blkCnt = numSamples;

#endif /* #ifndef ARM_MATH_CM0_FAMILY */

  while(blkCnt > 0u)

  {

    /* C[2 * i] = A[2 * i] * B[i].            */

    /* C[2 * i + 1] = A[2 * i + 1] * B[i].        */

    in = *pSrcReal++;

    /* store the result in the destination buffer. */

    *pCmplxDst++ = (*pSrcCmplx++) * (in);

    *pCmplxDst++ = (*pSrcCmplx++) * (in);

    /* Decrement the numSamples loop counter */

    blkCnt--;

  }

}

/**        

 * @} end of CmplxByRealMult group        

 */