lib/main/CMSIS/DSP/Source/SupportFunctions/arm_fill_q15.c

   1 /* ----------------------------------------------------------------------
   2  * Project:      CMSIS DSP Library
   3  * Title:        arm_fill_q15.c
   4  * Description:  Fills a constant value into a Q15 vector
   5  *
   6  * $Date:        27. January 2017
   7  * $Revision:    V.1.5.1
   8  *
   9  * Target Processor: Cortex-M cores
  10  * -------------------------------------------------------------------- */
  11 /*
  12  * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
  13  *
  14  * SPDX-License-Identifier: Apache-2.0
  15  *
  16  * Licensed under the Apache License, Version 2.0 (the License); you may
  17  * not use this file except in compliance with the License.
  18  * You may obtain a copy of the License at
  19  *
  20  * www.apache.org/licenses/LICENSE-2.0
  21  *
  22  * Unless required by applicable law or agreed to in writing, software
  23  * distributed under the License is distributed on an AS IS BASIS, WITHOUT
  24  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  25  * See the License for the specific language governing permissions and
  26  * limitations under the License.
  27  */
  28
  29 #include "arm_math.h"
  30
  31 /**
  32  * @ingroup groupSupport
  33  */
  34
  35 /**
  36  * @addtogroup Fill
  37  * @{
  38  */
  39
  40 /**
  41  * @brief Fills a constant value into a Q15 vector.
  42  * @param[in]       value input value to be filled
  43  * @param[out]      *pDst points to output vector
  44  * @param[in]       blockSize length of the output vector
  45  * @return none.
  46  *
  47  */
  48
  49 void arm_fill_q15(
  50   q15_t value,
  51   q15_t * pDst,
  52   uint32_t blockSize)
  53 {
  54   uint32_t blkCnt;                               /* loop counter */
  55
  56 #if defined (ARM_MATH_DSP)
  57
  58   /* Run the below code for Cortex-M4 and Cortex-M3 */
  59
  60   q31_t packedValue;                             /* value packed to 32 bits */
  61
  62
  63   /*loop Unrolling */
  64   blkCnt = blockSize >> 2U;
  65
  66   /* Packing two 16 bit values to 32 bit value in order to use SIMD */
  67   packedValue = __PKHBT(value, value, 16U);
  68
  69   /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.
  70    ** a second loop below computes the remaining 1 to 3 samples. */
  71   while (blkCnt > 0U)
  72   {
  73     /* C = value */
  74     /* Fill the value in the destination buffer */
  75     *__SIMD32(pDst)++ = packedValue;
  76     *__SIMD32(pDst)++ = packedValue;
  77
  78     /* Decrement the loop counter */
  79     blkCnt--;
  80   }
  81
  82   /* If the blockSize is not a multiple of 4, compute any remaining output samples here.
  83    ** No loop unrolling is used. */
  84   blkCnt = blockSize % 0x4U;
  85
  86 #else
  87
  88   /* Run the below code for Cortex-M0 */
  89
  90   /* Loop over blockSize number of values */
  91   blkCnt = blockSize;
  92
  93 #endif /* #if defined (ARM_MATH_DSP) */
  94
  95   while (blkCnt > 0U)
  96   {
  97     /* C = value */
  98     /* Fill the value in the destination buffer */
  99     *pDst++ = value;
 100
 101     /* Decrement the loop counter */
 102     blkCnt--;
 103   }
 104 }
 105
 106 /**
 107  * @} end of Fill group
 108  */