tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/ComplexMathFunctions/arm_cmplx_mult_real_f32.c

   1 /* ----------------------------------------------------------------------
   2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
   3 *
   4 * $Date:        17. January 2013
   5 * $Revision:    V1.4.1
   6 *
   7 * Project:          CMSIS DSP Library
   8 * Title:            arm_cmplx_mult_real_f32.c
   9 *
  10 * Description:  Floating-point complex by real multiplication
  11 *
  12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
  13 *
  14 * Redistribution and use in source and binary forms, with or without
  15 * modification, are permitted provided that the following conditions
  16 * are met:
  17 *   - Redistributions of source code must retain the above copyright
  18 *     notice, this list of conditions and the following disclaimer.
  19 *   - Redistributions in binary form must reproduce the above copyright
  20 *     notice, this list of conditions and the following disclaimer in
  21 *     the documentation and/or other materials provided with the
  22 *     distribution.
  23 *   - Neither the name of ARM LIMITED nor the names of its contributors
  24 *     may be used to endorse or promote products derived from this
  25 *     software without specific prior written permission.
  26 *
  27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  38 * POSSIBILITY OF SUCH DAMAGE.
  39 * -------------------------------------------------------------------- */
  40
  41 #include "arm_math.h"
  42
  43 /**
  44  * @ingroup groupCmplxMath
  45  */
  46
  47 /**
  48  * @defgroup CmplxByRealMult Complex-by-Real Multiplication
  49  *
  50  * Multiplies a complex vector by a real vector and generates a complex result.
  51  * The data in the complex arrays is stored in an interleaved fashion
  52  * (real, imag, real, imag, ...).
  53  * The parameter <code>numSamples</code> represents the number of complex
  54  * samples processed.  The complex arrays have a total of <code>2*numSamples</code>
  55  * real values while the real array has a total of <code>numSamples</code>
  56  * real values.
  57  *
  58  * The underlying algorithm is used:
  59  *
  60  * <pre>
  61  * for(n=0; n<numSamples; n++) {
  62  *     pCmplxDst[(2*n)+0] = pSrcCmplx[(2*n)+0] * pSrcReal[n];
  63  *     pCmplxDst[(2*n)+1] = pSrcCmplx[(2*n)+1] * pSrcReal[n];
  64  * }
  65  * </pre>
  66  *
  67  * There are separate functions for floating-point, Q15, and Q31 data types.
  68  */
  69
  70 /**
  71  * @addtogroup CmplxByRealMult
  72  * @{
  73  */
  74
  75
  76 /**
  77  * @brief  Floating-point complex-by-real multiplication
  78  * @param[in]  *pSrcCmplx points to the complex input vector
  79  * @param[in]  *pSrcReal points to the real input vector
  80  * @param[out]  *pCmplxDst points to the complex output vector
  81  * @param[in]  numSamples number of samples in each vector
  82  * @return none.
  83  */
  84
  85 void arm_cmplx_mult_real_f32(
  86   float32_t * pSrcCmplx,
  87   float32_t * pSrcReal,
  88   float32_t * pCmplxDst,
  89   uint32_t numSamples)
  90 {
  91   float32_t in;                                  /* Temporary variable to store input value */
  92   uint32_t blkCnt;                               /* loop counters */
  93
  94 #ifndef ARM_MATH_CM0_FAMILY
  95
  96   /* Run the below code for Cortex-M4 and Cortex-M3 */
  97   float32_t inA1, inA2, inA3, inA4;              /* Temporary variables to hold input data */
  98   float32_t inA5, inA6, inA7, inA8;              /* Temporary variables to hold input data */
  99   float32_t inB1, inB2, inB3, inB4;              /* Temporary variables to hold input data */
 100   float32_t out1, out2, out3, out4;              /* Temporary variables to hold output data */
 101   float32_t out5, out6, out7, out8;              /* Temporary variables to hold output data */
 102
 103   /* loop Unrolling */
 104   blkCnt = numSamples >> 2u;
 105
 106   /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.
 107    ** a second loop below computes the remaining 1 to 3 samples. */
 108   while(blkCnt > 0u)
 109   {
 110     /* C[2 * i] = A[2 * i] * B[i].            */
 111     /* C[2 * i + 1] = A[2 * i + 1] * B[i].        */
 112     /* read input from complex input buffer */
 113     inA1 = pSrcCmplx[0];
 114     inA2 = pSrcCmplx[1];
 115     /* read input from real input buffer */
 116     inB1 = pSrcReal[0];
 117
 118     /* read input from complex input buffer */
 119     inA3 = pSrcCmplx[2];
 120
 121     /* multiply complex buffer real input with real buffer input */
 122     out1 = inA1 * inB1;
 123
 124     /* read input from complex input buffer */
 125     inA4 = pSrcCmplx[3];
 126
 127     /* multiply complex buffer imaginary input with real buffer input */
 128     out2 = inA2 * inB1;
 129
 130     /* read input from real input buffer */
 131     inB2 = pSrcReal[1];
 132     /* read input from complex input buffer */
 133     inA5 = pSrcCmplx[4];
 134
 135     /* multiply complex buffer real input with real buffer input */
 136     out3 = inA3 * inB2;
 137
 138     /* read input from complex input buffer */
 139     inA6 = pSrcCmplx[5];
 140     /* read input from real input buffer */
 141     inB3 = pSrcReal[2];
 142
 143     /* multiply complex buffer imaginary input with real buffer input */
 144     out4 = inA4 * inB2;
 145
 146     /* read input from complex input buffer */
 147     inA7 = pSrcCmplx[6];
 148
 149     /* multiply complex buffer real input with real buffer input */
 150     out5 = inA5 * inB3;
 151
 152     /* read input from complex input buffer */
 153     inA8 = pSrcCmplx[7];
 154
 155     /* multiply complex buffer imaginary input with real buffer input */
 156     out6 = inA6 * inB3;
 157
 158     /* read input from real input buffer */
 159     inB4 = pSrcReal[3];
 160
 161     /* store result to destination bufer */
 162     pCmplxDst[0] = out1;
 163
 164     /* multiply complex buffer real input with real buffer input */
 165     out7 = inA7 * inB4;
 166
 167     /* store result to destination bufer */
 168     pCmplxDst[1] = out2;
 169
 170     /* multiply complex buffer imaginary input with real buffer input */
 171     out8 = inA8 * inB4;
 172
 173     /* store result to destination bufer */
 174     pCmplxDst[2] = out3;
 175     pCmplxDst[3] = out4;
 176     pCmplxDst[4] = out5;
 177
 178     /* incremnet complex input buffer by 8 to process next samples */
 179     pSrcCmplx += 8u;
 180
 181     /* store result to destination bufer */
 182     pCmplxDst[5] = out6;
 183
 184     /* increment real input buffer by 4 to process next samples */
 185     pSrcReal += 4u;
 186
 187     /* store result to destination bufer */
 188     pCmplxDst[6] = out7;
 189     pCmplxDst[7] = out8;
 190
 191     /* increment destination buffer by 8 to process next sampels */
 192     pCmplxDst += 8u;
 193
 194     /* Decrement the numSamples loop counter */
 195     blkCnt--;
 196   }
 197
 198   /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
 199    ** No loop unrolling is used. */
 200   blkCnt = numSamples % 0x4u;
 201
 202 #else
 203
 204   /* Run the below code for Cortex-M0 */
 205   blkCnt = numSamples;
 206
 207 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
 208
 209   while(blkCnt > 0u)
 210   {
 211     /* C[2 * i] = A[2 * i] * B[i].            */
 212     /* C[2 * i + 1] = A[2 * i + 1] * B[i].        */
 213     in = *pSrcReal++;
 214     /* store the result in the destination buffer. */
 215     *pCmplxDst++ = (*pSrcCmplx++) * (in);
 216     *pCmplxDst++ = (*pSrcCmplx++) * (in);
 217
 218     /* Decrement the numSamples loop counter */
 219     blkCnt--;
 220   }
 221 }
 222
 223 /**
 224  * @} end of CmplxByRealMult group
 225  */