text: /* ----------------------------------------------------------------------
  * Copyright (C) 2010 ARM Limited. All rights reserved.
  *
  * $Date:        15. February 2012
  * $Revision: 	V1.1.0
  *
  * Project: 	    CMSIS DSP Library
  * Title:	    arm_mat_add_q15.c
  *
  * Description:	Q15 matrix addition
  *
  * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
  *
  * Version 1.1.0 2012/02/15
  *    Updated with more optimizations, bug fixes and minor API changes.
  *
  * Version 1.0.10 2011/7/15
  *    Big Endian support added and Merged M0 and M3/M4 Source code.
  *
  * Version 1.0.3 2010/11/29
  *    Re-organized the CMSIS folders and updated documentation.
  *
  * Version 1.0.2 2010/11/11
  *    Documentation updated.
  *
  * Version 1.0.1 2010/10/05
  *    Production release and review comments incorporated.
  *
  * Version 1.0.0 2010/09/20
  *    Production release and review comments incorporated.
  *
  * Version 0.0.5  2010/04/26
  *    incorporated review comments and updated with latest CMSIS layer
  *
  * Version 0.0.3  2010/03/10
  *    Initial version
  * -------------------------------------------------------------------- */
  
  #include "arm_math.h"
  
  /**
   * @ingroup groupMatrix
   */
  
  /**
   * @addtogroup MatrixAdd
   * @{
   */
  
  /**
   * @brief Q15 matrix addition.
   * @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.
   *
   * <b>Scaling and Overflow Behavior:</b>
   * \par
   * The function uses saturating arithmetic.
   * Results outside of the allowable Q15 range [0x8000 0x7FFF] will be saturated.
   */
  
  arm_status arm_mat_add_q15(
      const arm_matrix_instance_q15* pSrcA,
      const arm_matrix_instance_q15* pSrcB,
      arm_matrix_instance_q15* pDst)
  {
  	q15_t* pInA = pSrcA->pData;                    /* input data matrix pointer A  */
  	q15_t* pInB = pSrcB->pData;                    /* input data matrix pointer B */
  	q15_t* pOut = pDst->pData;                     /* output data matrix pointer */
  	uint16_t numSamples;                           /* total number of elements in the matrix  */
  	uint32_t blkCnt;                               /* loop counters  */
  	arm_status status;                             /* status of matrix addition  */
  
  #ifdef ARM_MATH_MATRIX_CHECK
  
  
  	/* Check for matrix mismatch condition */
  	if((pSrcA->numRows != pSrcB->numRows) ||
  	        (pSrcA->numCols != pSrcB->numCols) ||
  	        (pSrcA->numRows != pDst->numRows) || (pSrcA->numCols != pDst->numCols)) {
  		/* Set status as ARM_MATH_SIZE_MISMATCH */
  		status = ARM_MATH_SIZE_MISMATCH;
  	} else
  #endif /*    #ifdef ARM_MATH_MATRIX_CHECK    */
  
  	{
  		/* Total number of samples in the input matrix */
  		numSamples = (uint16_t)(pSrcA->numRows * pSrcA->numCols);
  
  #ifndef ARM_MATH_CM0
  
  		/* Run the below code for Cortex-M4 and Cortex-M3 */
  
  		/* Loop unrolling */
  		blkCnt = (uint32_t) 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(m,n) = A(m,n) + B(m,n) */
  			/* Add, Saturate and then store the results in the destination buffer. */
  			*__SIMD32(pOut)++ = __QADD16(*__SIMD32(pInA)++, *__SIMD32(pInB)++);
  			*__SIMD32(pOut)++ = __QADD16(*__SIMD32(pInA)++, *__SIMD32(pInB)++);
  
  			/* Decrement the loop counter */
  			blkCnt--;
  		}
  
  		/* If the blockSize is not a multiple of 4, compute any remaining output samples here.
  		 ** No loop unrolling is used. */
  		blkCnt = (uint32_t) numSamples % 0x4u;
  
  		/* q15 pointers of input and output are initialized */
  
  		while(blkCnt > 0u) {
  			/* C(m,n) = A(m,n) + B(m,n) */
  			/* Add, Saturate and then store the results in the destination buffer. */
  			*pOut++ = (q15_t) __QADD16(*pInA++, *pInB++);
  
  			/* Decrement the loop counter */
  			blkCnt--;
  		}
  
  #else
  
  		/* Run the below code for Cortex-M0 */
  
  		/* Initialize blkCnt with number of samples */
  		blkCnt = (uint32_t) numSamples;
  
  
  		/* q15 pointers of input and output are initialized */
  		while(blkCnt > 0u) {
  			/* C(m,n) = A(m,n) + B(m,n) */
  			/* Add, Saturate and then store the results in the destination buffer. */
  			*pOut++ = (q15_t) __SSAT(((q31_t) * pInA++ + *pInB++), 16);
  
  			/* Decrement the loop counter */
  			blkCnt--;
  		}
  
  #endif /* #ifndef ARM_MATH_CM0 */
  
  		/* set status as ARM_MATH_SUCCESS */
  		status = ARM_MATH_SUCCESS;
  	}
  
  	/* Return to application */
  	return (status);
  }
  
  /**
   * @} end of MatrixAdd group
   */
  