arm_copy_q15.c

00001 /* ----------------------------------------------------------------------  
00002 * Copyright (C) 2010 ARM Limited. All rights reserved.  
00003 *  
00004 * $Date:        29. November 2010  
00005 * $Revision:    V1.0.3  
00006 *  
00007 * Project:      CMSIS DSP Library  
00008 * Title:        arm_copy_q15.c  
00009 *  
00010 * Description:  Processing function for the Q15 copy  
00011 *  
00012 * Target Processor: Cortex-M4/Cortex-M3
00013 *  
00014 * Version 1.0.3 2010/11/29 
00015 *    Re-organized the CMSIS folders and updated documentation.  
00016 *   
00017 * Version 1.0.2 2010/11/11  
00018 *    Documentation updated.   
00019 *  
00020 * Version 1.0.1 2010/10/05   
00021 *    Production release and review comments incorporated.  
00022 *  
00023 * Version 1.0.0 2010/09/20   
00024 *    Production release and review comments incorporated.  
00025 *  
00026 * Version 0.0.7  2010/06/10   
00027 *    Misra-C changes done  
00028 * -------------------------------------------------------------------- */ 
00029  
00030 #include "arm_math.h" 
00031  
00032 /**  
00033  * @ingroup groupSupport  
00034  */ 
00035  
00036 /**  
00037  * @addtogroup copy  
00038  * @{  
00039  */ 
00040 /**  
00041  * @brief Copies the elements of a Q15 vector.   
00042  * @param[in]       *pSrc points to input vector  
00043  * @param[out]      *pDst points to output vector  
00044  * @param[in]       blockSize length of the input vector 
00045  * @return none.  
00046  *  
00047  */ 
00048  
00049 void arm_copy_q15( 
00050   q15_t * pSrc, 
00051   q15_t * pDst, 
00052   uint32_t blockSize) 
00053 { 
00054   uint32_t blkCnt;                               /* loop counter */ 
00055   q15_t in1, in2;                                /* Temporary variables */ 
00056  
00057  
00058   /*loop Unrolling */ 
00059   blkCnt = blockSize >> 2u; 
00060  
00061   /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.  
00062    ** a second loop below computes the remaining 1 to 3 samples. */ 
00063   while(blkCnt > 0u) 
00064   { 
00065     /* C = A */ 
00066     /* Read two inputs */ 
00067     in1 = *pSrc++; 
00068     in2 = *pSrc++; 
00069     /* Store the values in the destination buffer by packing the two inputs */ 
00070     *__SIMD32(pDst)++ = __PKHBT(in1, in2, 16); 
00071  
00072     in1 = *pSrc++; 
00073     in2 = *pSrc++; 
00074     *__SIMD32(pDst)++ = __PKHBT(in1, in2, 16); 
00075  
00076     /* Decrement the loop counter */ 
00077     blkCnt--; 
00078   } 
00079  
00080   /* If the blockSize is not a multiple of 4, compute any remaining output samples here.  
00081    ** No loop unrolling is used. */ 
00082   blkCnt = blockSize % 0x4u; 
00083  
00084   while(blkCnt > 0u) 
00085   { 
00086     /* C = A */ 
00087     /* Copy and then store the value in the destination buffer */ 
00088     *pDst++ = *pSrc++; 
00089  
00090     /* Decrement the loop counter */ 
00091     blkCnt--; 
00092   } 
00093 } 
00094  
00095 /**  
00096  * @} end of BasicCopy group  
00097  */