tmk_core/tool/mbed/mbed-sdk/libraries/dsp/cmsis_dsp/SupportFunctions/arm_q7_to_q31.c

   1 /* ----------------------------------------------------------------------------
   2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
   3 *
   4 * $Date:        17. January 2013
   5 * $Revision:    V1.4.1
   6 *
   7 * Project:          CMSIS DSP Library
   8 * Title:                arm_q7_to_q31.c
   9 *
  10 * Description:  Converts the elements of the Q7 vector to Q31 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  * @brief Converts the elements of the Q7 vector to Q31 vector.
  54  * @param[in]       *pSrc points to the Q7 input vector
  55  * @param[out]      *pDst points to the Q31 output vector
  56  * @param[in]       blockSize length of the input vector
  57  * @return none.
  58  *
  59  * \par Description:
  60  *
  61  * The equation used for the conversion process is:
  62  *
  63  * <pre>
  64  *      pDst[n] = (q31_t) pSrc[n] << 24;   0 <= n < blockSize.
  65  * </pre>
  66  *
  67  */
  68
  69
  70 void arm_q7_to_q31(
  71   q7_t * pSrc,
  72   q31_t * pDst,
  73   uint32_t blockSize)
  74 {
  75   q7_t *pIn = pSrc;                              /* Src pointer */
  76   uint32_t blkCnt;                               /* loop counter */
  77
  78 #ifndef ARM_MATH_CM0_FAMILY
  79
  80   q31_t in;
  81
  82   /* Run the below code for Cortex-M4 and Cortex-M3 */
  83
  84   /*loop Unrolling */
  85   blkCnt = blockSize >> 2u;
  86
  87   /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.
  88    ** a second loop below computes the remaining 1 to 3 samples. */
  89   while(blkCnt > 0u)
  90   {
  91     /* C = (q31_t) A << 24 */
  92     /* convert from q7 to q31 and then store the results in the destination buffer */
  93     in = *__SIMD32(pIn)++;
  94
  95 #ifndef ARM_MATH_BIG_ENDIAN
  96
  97     *pDst++ = (__ROR(in, 8)) & 0xFF000000;
  98     *pDst++ = (__ROR(in, 16)) & 0xFF000000;
  99     *pDst++ = (__ROR(in, 24)) & 0xFF000000;
 100     *pDst++ = (in & 0xFF000000);
 101
 102 #else
 103
 104     *pDst++ = (in & 0xFF000000);
 105     *pDst++ = (__ROR(in, 24)) & 0xFF000000;
 106     *pDst++ = (__ROR(in, 16)) & 0xFF000000;
 107     *pDst++ = (__ROR(in, 8)) & 0xFF000000;
 108
 109 #endif //              #ifndef ARM_MATH_BIG_ENDIAN
 110
 111     /* Decrement the loop counter */
 112     blkCnt--;
 113   }
 114
 115   /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
 116    ** No loop unrolling is used. */
 117   blkCnt = blockSize % 0x4u;
 118
 119 #else
 120
 121   /* Run the below code for Cortex-M0 */
 122
 123   /* Loop over blockSize number of values */
 124   blkCnt = blockSize;
 125
 126 #endif /* #ifndef ARM_MATH_CM0_FAMILY */
 127
 128   while(blkCnt > 0u)
 129   {
 130     /* C = (q31_t) A << 24 */
 131     /* convert from q7 to q31 and then store the results in the destination buffer */
 132     *pDst++ = (q31_t) * pIn++ << 24;
 133
 134     /* Decrement the loop counter */
 135     blkCnt--;
 136   }
 137
 138 }
 139
 140 /**
 141  * @} end of q7_to_x group
 142  */