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/* ----------------------------------------------------------------------------    
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* Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
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*    
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* $Date:        19. March 2015
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* $Revision:    V.1.4.5  
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*    
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* Project:          CMSIS DSP Library    
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* Title:                arm_q7_to_q15.c    
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*    
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* Description:  Converts the elements of the Q7 vector to Q15 vector.    
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*    
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* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
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*  
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*   - Redistributions of source code must retain the above copyright
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*     notice, this list of conditions and the following disclaimer.
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*   - Redistributions in binary form must reproduce the above copyright
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*     notice, this list of conditions and the following disclaimer in
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*     the documentation and/or other materials provided with the
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*     distribution.
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*   - Neither the name of ARM LIMITED nor the names of its contributors
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*     may be used to endorse or promote products derived from this
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*     software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.  
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* ---------------------------------------------------------------------------- */
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#include "arm_math.h"
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/**    
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 * @ingroup groupSupport    
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 */
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/**    
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 * @addtogroup q7_to_x    
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 * @{    
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 */
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/**    
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 * @brief Converts the elements of the Q7 vector to Q15 vector.    
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 * @param[in]       *pSrc points to the Q7 input vector    
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 * @param[out]      *pDst points to the Q15 output vector  
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 * @param[in]       blockSize length of the input vector    
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 * @return none.    
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 *    
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 * \par Description:    
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 *    
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 * The equation used for the conversion process is:    
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 *  
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 * <pre>    
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 *      pDst[n] = (q15_t) pSrc[n] << 8;   0 <= n < blockSize.    
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 * </pre>    
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 *  
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 */
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void arm_q7_to_q15(
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  q7_t * pSrc,
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  q15_t * pDst,
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  uint32_t blockSize)
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{
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  q7_t *pIn = pSrc;                              /* Src pointer */
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  uint32_t blkCnt;                               /* loop counter */
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#ifndef ARM_MATH_CM0_FAMILY
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  q31_t in;
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  q31_t in1, in2;
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  q31_t out1, out2;
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  /* Run the below code for Cortex-M4 and Cortex-M3 */
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  /*loop Unrolling */
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  blkCnt = blockSize >> 2u;
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  /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.    
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   ** a second loop below computes the remaining 1 to 3 samples. */
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  while(blkCnt > 0u)
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  {
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    /* C = (q15_t) A << 8 */
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    /* convert from q7 to q15 and then store the results in the destination buffer */
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    in = *__SIMD32(pIn)++;
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    /* rotatate in by 8 and extend two q7_t values to q15_t values */
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    in1 = __SXTB16(__ROR(in, 8));
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    /* extend remainig two q7_t values to q15_t values */
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    in2 = __SXTB16(in);
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    in1 = in1 << 8u;
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    in2 = in2 << 8u;
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    in1 = in1 & 0xFF00FF00;
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    in2 = in2 & 0xFF00FF00;
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#ifndef ARM_MATH_BIG_ENDIAN
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    out2 = __PKHTB(in1, in2, 16);
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    out1 = __PKHBT(in2, in1, 16);
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#else
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    out1 = __PKHTB(in1, in2, 16);
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    out2 = __PKHBT(in2, in1, 16);
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#endif
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    *__SIMD32(pDst)++ = out1;
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    *__SIMD32(pDst)++ = out2;
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    /* Decrement the loop counter */
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    blkCnt--;
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  }
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  /* If the blockSize is not a multiple of 4, compute any remaining output samples here.    
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   ** No loop unrolling is used. */
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  blkCnt = blockSize % 0x4u;
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#else
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  /* Run the below code for Cortex-M0 */
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  /* Loop over blockSize number of values */
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  blkCnt = blockSize;
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#endif /* #ifndef ARM_MATH_CM0_FAMILY */
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  while(blkCnt > 0u)
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  {
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    /* C = (q15_t) A << 8 */
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    /* convert from q7 to q15 and then store the results in the destination buffer */
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    *pDst++ = (q15_t) * pIn++ << 8;
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    /* Decrement the loop counter */
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    blkCnt--;
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  }
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}
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/**    
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 * @} end of q7_to_x group    
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 */