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  1. /* ----------------------------------------------------------------------------    
  2. * Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
  3. *    
  4. * $Date:        19. March 2015
  5. * $Revision:    V.1.4.5  
  6. *    
  7. * Project:          CMSIS DSP Library    
  8. * Title:                arm_q7_to_q15.c    
  9. *    
  10. * Description:  Converts the elements of the Q7 vector to Q15 vector.    
  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 groupSupport    
  45.  */
  46.  
  47. /**    
  48.  * @addtogroup q7_to_x    
  49.  * @{    
  50.  */
  51.  
  52.  
  53.  
  54.  
  55. /**    
  56.  * @brief Converts the elements of the Q7 vector to Q15 vector.    
  57.  * @param[in]       *pSrc points to the Q7 input vector    
  58.  * @param[out]      *pDst points to the Q15 output vector  
  59.  * @param[in]       blockSize length of the input vector    
  60.  * @return none.    
  61.  *    
  62.  * \par Description:    
  63.  *    
  64.  * The equation used for the conversion process is:    
  65.  *  
  66.  * <pre>    
  67.  *      pDst[n] = (q15_t) pSrc[n] << 8;   0 <= n < blockSize.    
  68.  * </pre>    
  69.  *  
  70.  */
  71.  
  72.  
  73. void arm_q7_to_q15(
  74.   q7_t * pSrc,
  75.   q15_t * pDst,
  76.   uint32_t blockSize)
  77. {
  78.   q7_t *pIn = pSrc;                              /* Src pointer */
  79.   uint32_t blkCnt;                               /* loop counter */
  80.  
  81. #ifndef ARM_MATH_CM0_FAMILY
  82.   q31_t in;
  83.   q31_t in1, in2;
  84.   q31_t out1, out2;
  85.  
  86.   /* Run the below code for Cortex-M4 and Cortex-M3 */
  87.  
  88.   /*loop Unrolling */
  89.   blkCnt = blockSize >> 2u;
  90.  
  91.   /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.    
  92.    ** a second loop below computes the remaining 1 to 3 samples. */
  93.   while(blkCnt > 0u)
  94.   {
  95.     /* C = (q15_t) A << 8 */
  96.     /* convert from q7 to q15 and then store the results in the destination buffer */
  97.     in = *__SIMD32(pIn)++;
  98.  
  99.     /* rotatate in by 8 and extend two q7_t values to q15_t values */
  100.     in1 = __SXTB16(__ROR(in, 8));
  101.  
  102.     /* extend remainig two q7_t values to q15_t values */
  103.     in2 = __SXTB16(in);
  104.  
  105.     in1 = in1 << 8u;
  106.     in2 = in2 << 8u;
  107.  
  108.     in1 = in1 & 0xFF00FF00;
  109.     in2 = in2 & 0xFF00FF00;
  110.  
  111. #ifndef ARM_MATH_BIG_ENDIAN
  112.  
  113.     out2 = __PKHTB(in1, in2, 16);
  114.     out1 = __PKHBT(in2, in1, 16);
  115.  
  116. #else
  117.  
  118.     out1 = __PKHTB(in1, in2, 16);
  119.     out2 = __PKHBT(in2, in1, 16);
  120.  
  121. #endif
  122.  
  123.     *__SIMD32(pDst)++ = out1;
  124.     *__SIMD32(pDst)++ = out2;
  125.  
  126.     /* Decrement the loop counter */
  127.     blkCnt--;
  128.   }
  129.  
  130.   /* If the blockSize is not a multiple of 4, compute any remaining output samples here.    
  131.    ** No loop unrolling is used. */
  132.   blkCnt = blockSize % 0x4u;
  133.  
  134. #else
  135.  
  136.   /* Run the below code for Cortex-M0 */
  137.  
  138.   /* Loop over blockSize number of values */
  139.   blkCnt = blockSize;
  140.  
  141. #endif /* #ifndef ARM_MATH_CM0_FAMILY */
  142.  
  143.   while(blkCnt > 0u)
  144.   {
  145.     /* C = (q15_t) A << 8 */
  146.     /* convert from q7 to q15 and then store the results in the destination buffer */
  147.     *pDst++ = (q15_t) * pIn++ << 8;
  148.  
  149.     /* Decrement the loop counter */
  150.     blkCnt--;
  151.   }
  152.  
  153. }
  154.  
  155. /**    
  156.  * @} end of q7_to_x group    
  157.  */
  158.