Subversion Repositories AFRtranscoder

Rev

Blame | Last modification | View Log | Download | RSS feed

  1. /* ----------------------------------------------------------------------
  2.  * Project:      CMSIS DSP Library
  3.  * Title:        arm_mat_scale_q15.c
  4.  * Description:  Multiplies a Q15 matrix by a scalar
  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 groupMatrix
  33.  */
  34.  
  35. /**
  36.  * @addtogroup MatrixScale
  37.  * @{
  38.  */
  39.  
  40. /**
  41.  * @brief Q15 matrix scaling.
  42.  * @param[in]       *pSrc points to input matrix
  43.  * @param[in]       scaleFract fractional portion of the scale factor
  44.  * @param[in]       shift number of bits to shift the result by
  45.  * @param[out]      *pDst points to output matrix structure
  46.  * @return              The function returns either
  47.  * <code>ARM_MATH_SIZE_MISMATCH</code> or <code>ARM_MATH_SUCCESS</code> based on the outcome of size checking.
  48.  *
  49.  * @details
  50.  * <b>Scaling and Overflow Behavior:</b>
  51.  * \par
  52.  * The input data <code>*pSrc</code> and <code>scaleFract</code> are in 1.15 format.
  53.  * These are multiplied to yield a 2.30 intermediate result and this is shifted with saturation to 1.15 format.
  54.  */
  55.  
  56. arm_status arm_mat_scale_q15(
  57.   const arm_matrix_instance_q15 * pSrc,
  58.   q15_t scaleFract,
  59.   int32_t shift,
  60.   arm_matrix_instance_q15 * pDst)
  61. {
  62.   q15_t *pIn = pSrc->pData;                      /* input data matrix pointer */
  63.   q15_t *pOut = pDst->pData;                     /* output data matrix pointer */
  64.   uint32_t numSamples;                           /* total number of elements in the matrix */
  65.   int32_t totShift = 15 - shift;                 /* total shift to apply after scaling */
  66.   uint32_t blkCnt;                               /* loop counters */
  67.   arm_status status;                             /* status of matrix scaling     */
  68.  
  69. #if defined (ARM_MATH_DSP)
  70.  
  71.   q15_t in1, in2, in3, in4;
  72.   q31_t out1, out2, out3, out4;
  73.   q31_t inA1, inA2;
  74.  
  75. #endif //     #if defined (ARM_MATH_DSP)
  76.  
  77. #ifdef ARM_MATH_MATRIX_CHECK
  78.   /* Check for matrix mismatch */
  79.   if ((pSrc->numRows != pDst->numRows) || (pSrc->numCols != pDst->numCols))
  80.   {
  81.     /* Set status as ARM_MATH_SIZE_MISMATCH */
  82.     status = ARM_MATH_SIZE_MISMATCH;
  83.   }
  84.   else
  85. #endif //    #ifdef ARM_MATH_MATRIX_CHECK
  86.   {
  87.     /* Total number of samples in the input matrix */
  88.     numSamples = (uint32_t) pSrc->numRows * pSrc->numCols;
  89.  
  90. #if defined (ARM_MATH_DSP)
  91.  
  92.     /* Run the below code for Cortex-M4 and Cortex-M3 */
  93.     /* Loop Unrolling */
  94.     blkCnt = numSamples >> 2;
  95.  
  96.     /* First part of the processing with loop unrolling.  Compute 4 outputs at a time.
  97.      ** a second loop below computes the remaining 1 to 3 samples. */
  98.     while (blkCnt > 0U)
  99.     {
  100.       /* C(m,n) = A(m,n) * k */
  101.       /* Scale, saturate and then store the results in the destination buffer. */
  102.       /* Reading 2 inputs from memory */
  103.       inA1 = _SIMD32_OFFSET(pIn);
  104.       inA2 = _SIMD32_OFFSET(pIn + 2);
  105.  
  106.       /* C = A * scale */
  107.       /* Scale the inputs and then store the 2 results in the destination buffer
  108.        * in single cycle by packing the outputs */
  109.       out1 = (q31_t) ((q15_t) (inA1 >> 16) * scaleFract);
  110.       out2 = (q31_t) ((q15_t) inA1 * scaleFract);
  111.       out3 = (q31_t) ((q15_t) (inA2 >> 16) * scaleFract);
  112.       out4 = (q31_t) ((q15_t) inA2 * scaleFract);
  113.  
  114.       out1 = out1 >> totShift;
  115.       inA1 = _SIMD32_OFFSET(pIn + 4);
  116.       out2 = out2 >> totShift;
  117.       inA2 = _SIMD32_OFFSET(pIn + 6);
  118.       out3 = out3 >> totShift;
  119.       out4 = out4 >> totShift;
  120.  
  121.       in1 = (q15_t) (__SSAT(out1, 16));
  122.       in2 = (q15_t) (__SSAT(out2, 16));
  123.       in3 = (q15_t) (__SSAT(out3, 16));
  124.       in4 = (q15_t) (__SSAT(out4, 16));
  125.  
  126.       _SIMD32_OFFSET(pOut) = __PKHBT(in2, in1, 16);
  127.       _SIMD32_OFFSET(pOut + 2) = __PKHBT(in4, in3, 16);
  128.  
  129.       /* update pointers to process next sampels */
  130.       pIn += 4U;
  131.       pOut += 4U;
  132.  
  133.  
  134.       /* Decrement the numSamples loop counter */
  135.       blkCnt--;
  136.     }
  137.  
  138.     /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
  139.      ** No loop unrolling is used. */
  140.     blkCnt = numSamples % 0x4U;
  141.  
  142. #else
  143.  
  144.     /* Run the below code for Cortex-M0 */
  145.  
  146.     /* Initialize blkCnt with number of samples */
  147.     blkCnt = numSamples;
  148.  
  149. #endif /* #if defined (ARM_MATH_DSP) */
  150.  
  151.     while (blkCnt > 0U)
  152.     {
  153.       /* C(m,n) = A(m,n) * k */
  154.       /* Scale, saturate and then store the results in the destination buffer. */
  155.       *pOut++ =
  156.         (q15_t) (__SSAT(((q31_t) (*pIn++) * scaleFract) >> totShift, 16));
  157.  
  158.       /* Decrement the numSamples loop counter */
  159.       blkCnt--;
  160.     }
  161.     /* Set status as ARM_MATH_SUCCESS */
  162.     status = ARM_MATH_SUCCESS;
  163.   }
  164.  
  165.   /* Return to application */
  166.   return (status);
  167. }
  168.  
  169. /**
  170.  * @} end of MatrixScale group
  171.  */
  172.