text: /* ----------------------------------------------------------------------    
  * Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
  *    
  * $Date:        19. March 2015
  * $Revision: 	V.1.4.5
  *    
  * Project: 	    CMSIS DSP Library    
  * Title:	    arm_mat_mult_f32.c    
  *    
  * Description:  Floating-point matrix 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
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  * POSSIBILITY OF SUCH DAMAGE.  
  * -------------------------------------------------------------------- */
  
  #include "../../../../../drivers/CMSIS/Include/arm_math.h"
  
  /**    
   * @ingroup groupMatrix    
   */
  
  /**    
   * @defgroup MatrixMult Matrix Multiplication    
   *    
   * Multiplies two matrices.    
   *    
   * \image html MatrixMultiplication.gif "Multiplication of two 3 x 3 matrices"    
      
   * Matrix multiplication is only defined if the number of columns of the    
   * first matrix equals the number of rows of the second matrix.    
   * Multiplying an <code>M x N</code> matrix with an <code>N x P</code> matrix results    
   * in an <code>M x P</code> matrix.    
   * When matrix size checking is enabled, the functions check: (1) that the inner dimensions of    
   * <code>pSrcA</code> and <code>pSrcB</code> are equal; and (2) that the size of the output    
   * matrix equals the outer dimensions of <code>pSrcA</code> and <code>pSrcB</code>.    
   */
  
  
  /**    
   * @addtogroup MatrixMult    
   * @{    
   */
  
  /**    
   * @brief Floating-point matrix multiplication.    
   * @param[in]       *pSrcA points to the first input matrix structure    
   * @param[in]       *pSrcB points to the second input matrix structure    
   * @param[out]      *pDst points to output matrix structure    
   * @return     		The function returns either    
   * <code>ARM_MATH_SIZE_MISMATCH</code> or <code>ARM_MATH_SUCCESS</code> based on the outcome of size checking.    
   */
  
  arm_status arm_mat_mult_f32(
    const arm_matrix_instance_f32 * pSrcA,
    const arm_matrix_instance_f32 * pSrcB,
    arm_matrix_instance_f32 * pDst)
  {
    float32_t *pIn1 = pSrcA->pData;                /* input data matrix pointer A */
    float32_t *pIn2 = pSrcB->pData;                /* input data matrix pointer B */
    float32_t *pInA = pSrcA->pData;                /* input data matrix pointer A  */
    float32_t *pOut = pDst->pData;                 /* output data matrix pointer */
    float32_t *px;                                 /* Temporary output data matrix pointer */
    float32_t sum;                                 /* Accumulator */
    uint16_t numRowsA = pSrcA->numRows;            /* number of rows of input matrix A */
    uint16_t numColsB = pSrcB->numCols;            /* number of columns of input matrix B */
    uint16_t numColsA = pSrcA->numCols;            /* number of columns of input matrix A */
  
  #ifndef ARM_MATH_CM0_FAMILY
  
    /* Run the below code for Cortex-M4 and Cortex-M3 */
  
    float32_t in1, in2, in3, in4;
    uint16_t col, i = 0u, j, row = numRowsA, colCnt;      /* loop counters */
    arm_status status;                             /* status of matrix multiplication */
  
  #ifdef ARM_MATH_MATRIX_CHECK
  
  
    /* Check for matrix mismatch condition */
    if((pSrcA->numCols != pSrcB->numRows) ||
       (pSrcA->numRows != pDst->numRows) || (pSrcB->numCols != pDst->numCols))
    {
  
      /* Set status as ARM_MATH_SIZE_MISMATCH */
      status = ARM_MATH_SIZE_MISMATCH;
    }
    else
  #endif /*      #ifdef ARM_MATH_MATRIX_CHECK    */
  
    {
      /* The following loop performs the dot-product of each row in pSrcA with each column in pSrcB */
      /* row loop */
      do
      {
        /* Output pointer is set to starting address of the row being processed */
        px = pOut + i;
  
        /* For every row wise process, the column loop counter is to be initiated */
        col = numColsB;
  
        /* For every row wise process, the pIn2 pointer is set    
         ** to the starting address of the pSrcB data */
        pIn2 = pSrcB->pData;
  
        j = 0u;
  
        /* column loop */
        do
        {
          /* Set the variable sum, that acts as accumulator, to zero */
          sum = 0.0f;
  
          /* Initiate the pointer pIn1 to point to the starting address of the column being processed */
          pIn1 = pInA;
  
          /* Apply loop unrolling and compute 4 MACs simultaneously. */
          colCnt = numColsA >> 2u;
  
          /* matrix multiplication        */
          while(colCnt > 0u)
          {
            /* c(m,n) = a(1,1)*b(1,1) + a(1,2) * b(2,1) + .... + a(m,p)*b(p,n) */
            in3 = *pIn2;
            pIn2 += numColsB;
            in1 = pIn1[0];
            in2 = pIn1[1];
            sum += in1 * in3;
            in4 = *pIn2;
            pIn2 += numColsB;
            sum += in2 * in4;
  
            in3 = *pIn2;
            pIn2 += numColsB;
            in1 = pIn1[2];
            in2 = pIn1[3];
            sum += in1 * in3;
            in4 = *pIn2;
            pIn2 += numColsB;
            sum += in2 * in4;
            pIn1 += 4u;
  
            /* Decrement the loop count */
            colCnt--;
          }
  
          /* If the columns of pSrcA is not a multiple of 4, compute any remaining MACs here.    
           ** No loop unrolling is used. */
          colCnt = numColsA % 0x4u;
  
          while(colCnt > 0u)
          {
            /* c(m,n) = a(1,1)*b(1,1) + a(1,2) * b(2,1) + .... + a(m,p)*b(p,n) */
            sum += *pIn1++ * (*pIn2);
            pIn2 += numColsB;
  
            /* Decrement the loop counter */
            colCnt--;
          }
  
          /* Store the result in the destination buffer */
          *px++ = sum;
  
          /* Update the pointer pIn2 to point to the  starting address of the next column */
          j++;
          pIn2 = pSrcB->pData + j;
  
          /* Decrement the column loop counter */
          col--;
  
        } while(col > 0u);
  
  #else
  
    /* Run the below code for Cortex-M0 */
  
    float32_t *pInB = pSrcB->pData;                /* input data matrix pointer B */
    uint16_t col, i = 0u, row = numRowsA, colCnt;  /* loop counters */
    arm_status status;                             /* status of matrix multiplication */
  
  #ifdef ARM_MATH_MATRIX_CHECK
  
    /* Check for matrix mismatch condition */
    if((pSrcA->numCols != pSrcB->numRows) ||
       (pSrcA->numRows != pDst->numRows) || (pSrcB->numCols != pDst->numCols))
    {
  
      /* Set status as ARM_MATH_SIZE_MISMATCH */
      status = ARM_MATH_SIZE_MISMATCH;
    }
    else
  #endif /*      #ifdef ARM_MATH_MATRIX_CHECK    */
  
    {
      /* The following loop performs the dot-product of each row in pInA with each column in pInB */
      /* row loop */
      do
      {
        /* Output pointer is set to starting address of the row being processed */
        px = pOut + i;
  
        /* For every row wise process, the column loop counter is to be initiated */
        col = numColsB;
  
        /* For every row wise process, the pIn2 pointer is set     
         ** to the starting address of the pSrcB data */
        pIn2 = pSrcB->pData;
  
        /* column loop */
        do
        {
          /* Set the variable sum, that acts as accumulator, to zero */
          sum = 0.0f;
  
          /* Initialize the pointer pIn1 to point to the starting address of the row being processed */
          pIn1 = pInA;
  
          /* Matrix A columns number of MAC operations are to be performed */
          colCnt = numColsA;
  
          while(colCnt > 0u)
          {
            /* c(m,n) = a(1,1)*b(1,1) + a(1,2) * b(2,1) + .... + a(m,p)*b(p,n) */
            sum += *pIn1++ * (*pIn2);
            pIn2 += numColsB;
  
            /* Decrement the loop counter */
            colCnt--;
          }
  
          /* Store the result in the destination buffer */
          *px++ = sum;
  
          /* Decrement the column loop counter */
          col--;
  
          /* Update the pointer pIn2 to point to the  starting address of the next column */
          pIn2 = pInB + (numColsB - col);
  
        } while(col > 0u);
  
  #endif /* #ifndef ARM_MATH_CM0_FAMILY */
  
        /* Update the pointer pInA to point to the  starting address of the next row */
        i = i + numColsB;
        pInA = pInA + numColsA;
  
        /* Decrement the row loop counter */
        row--;
  
      } while(row > 0u);
      /* Set status as ARM_MATH_SUCCESS */
      status = ARM_MATH_SUCCESS;
    }
  
    /* Return to application */
    return (status);
  }
  
  /**    
   * @} end of MatrixMult group    
   */
  