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CMSIS DSP Lib

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cmsis_dsp/MatrixFunctions/arm_mat_scale_q31.c@1:fdd22bb7aa52, 2012-11-28 (annotated)

Committer:
emilmont
Date:
Wed Nov 28 12:30:09 2012 +0000
Revision:
1:fdd22bb7aa52
Child:
2:da51fb522205
DSP library code

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
emilmont 1:fdd22bb7aa52 2 * Copyright (C) 2010 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
emilmont 1:fdd22bb7aa52 4 * $Date: 15. February 2012
emilmont 1:fdd22bb7aa52 5 * $Revision: V1.1.0
emilmont 1:fdd22bb7aa52 6 *
emilmont 1:fdd22bb7aa52 7 * Project: CMSIS DSP Library
emilmont 1:fdd22bb7aa52 8 * Title: arm_mat_scale_q31.c
emilmont 1:fdd22bb7aa52 9 *
emilmont 1:fdd22bb7aa52 10 * Description: Multiplies a Q31 matrix by a scalar.
emilmont 1:fdd22bb7aa52 11 *
emilmont 1:fdd22bb7aa52 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
emilmont 1:fdd22bb7aa52 13 *
emilmont 1:fdd22bb7aa52 14 * Version 1.1.0 2012/02/15
emilmont 1:fdd22bb7aa52 15 * Updated with more optimizations, bug fixes and minor API changes.
emilmont 1:fdd22bb7aa52 16 *
emilmont 1:fdd22bb7aa52 17 * Version 1.0.10 2011/7/15
emilmont 1:fdd22bb7aa52 18 * Big Endian support added and Merged M0 and M3/M4 Source code.
emilmont 1:fdd22bb7aa52 19 *
emilmont 1:fdd22bb7aa52 20 * Version 1.0.3 2010/11/29
emilmont 1:fdd22bb7aa52 21 * Re-organized the CMSIS folders and updated documentation.
emilmont 1:fdd22bb7aa52 22 *
emilmont 1:fdd22bb7aa52 23 * Version 1.0.2 2010/11/11
emilmont 1:fdd22bb7aa52 24 * Documentation updated.
emilmont 1:fdd22bb7aa52 25 *
emilmont 1:fdd22bb7aa52 26 * Version 1.0.1 2010/10/05
emilmont 1:fdd22bb7aa52 27 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 28 *
emilmont 1:fdd22bb7aa52 29 * Version 1.0.0 2010/09/20
emilmont 1:fdd22bb7aa52 30 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 31 *
emilmont 1:fdd22bb7aa52 32 * Version 0.0.5 2010/04/26
emilmont 1:fdd22bb7aa52 33 * incorporated review comments and updated with latest CMSIS layer
emilmont 1:fdd22bb7aa52 34 *
emilmont 1:fdd22bb7aa52 35 * Version 0.0.3 2010/03/10
emilmont 1:fdd22bb7aa52 36 * Initial version
emilmont 1:fdd22bb7aa52 37 * -------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 38
emilmont 1:fdd22bb7aa52 39 #include "arm_math.h"
emilmont 1:fdd22bb7aa52 40
emilmont 1:fdd22bb7aa52 41 /**
emilmont 1:fdd22bb7aa52 42 * @ingroup groupMatrix
emilmont 1:fdd22bb7aa52 43 */
emilmont 1:fdd22bb7aa52 44
emilmont 1:fdd22bb7aa52 45 /**
emilmont 1:fdd22bb7aa52 46 * @addtogroup MatrixScale
emilmont 1:fdd22bb7aa52 47 * @{
emilmont 1:fdd22bb7aa52 48 */
emilmont 1:fdd22bb7aa52 49
emilmont 1:fdd22bb7aa52 50 /**
emilmont 1:fdd22bb7aa52 51 * @brief Q31 matrix scaling.
emilmont 1:fdd22bb7aa52 52 * @param[in] *pSrc points to input matrix
emilmont 1:fdd22bb7aa52 53 * @param[in] scaleFract fractional portion of the scale factor
emilmont 1:fdd22bb7aa52 54 * @param[in] shift number of bits to shift the result by
emilmont 1:fdd22bb7aa52 55 * @param[out] *pDst points to output matrix structure
emilmont 1:fdd22bb7aa52 56 * @return The function returns either
emilmont 1:fdd22bb7aa52 57 * <code>ARM_MATH_SIZE_MISMATCH</code> or <code>ARM_MATH_SUCCESS</code> based on the outcome of size checking.
emilmont 1:fdd22bb7aa52 58 *
emilmont 1:fdd22bb7aa52 59 * @details
emilmont 1:fdd22bb7aa52 60 * <b>Scaling and Overflow Behavior:</b>
emilmont 1:fdd22bb7aa52 61 * \par
emilmont 1:fdd22bb7aa52 62 * The input data <code>*pSrc</code> and <code>scaleFract</code> are in 1.31 format.
emilmont 1:fdd22bb7aa52 63 * These are multiplied to yield a 2.62 intermediate result and this is shifted with saturation to 1.31 format.
emilmont 1:fdd22bb7aa52 64 */
emilmont 1:fdd22bb7aa52 65
emilmont 1:fdd22bb7aa52 66 arm_status arm_mat_scale_q31(
emilmont 1:fdd22bb7aa52 67 const arm_matrix_instance_q31 * pSrc,
emilmont 1:fdd22bb7aa52 68 q31_t scaleFract,
emilmont 1:fdd22bb7aa52 69 int32_t shift,
emilmont 1:fdd22bb7aa52 70 arm_matrix_instance_q31 * pDst)
emilmont 1:fdd22bb7aa52 71 {
emilmont 1:fdd22bb7aa52 72 q31_t *pIn = pSrc->pData; /* input data matrix pointer */
emilmont 1:fdd22bb7aa52 73 q31_t *pOut = pDst->pData; /* output data matrix pointer */
emilmont 1:fdd22bb7aa52 74 uint32_t numSamples; /* total number of elements in the matrix */
emilmont 1:fdd22bb7aa52 75 int32_t totShift = shift + 1; /* shift to apply after scaling */
emilmont 1:fdd22bb7aa52 76 uint32_t blkCnt; /* loop counters */
emilmont 1:fdd22bb7aa52 77 arm_status status; /* status of matrix scaling */
emilmont 1:fdd22bb7aa52 78 q31_t in1, in2, out1; /* temporary variabels */
emilmont 1:fdd22bb7aa52 79
emilmont 1:fdd22bb7aa52 80 #ifndef ARM_MATH_CM0
emilmont 1:fdd22bb7aa52 81
emilmont 1:fdd22bb7aa52 82 q31_t in3, in4, out2, out3, out4; /* temporary variables */
emilmont 1:fdd22bb7aa52 83
emilmont 1:fdd22bb7aa52 84 #endif // #ifndef ARM_MAT_CM0
emilmont 1:fdd22bb7aa52 85
emilmont 1:fdd22bb7aa52 86 #ifdef ARM_MATH_MATRIX_CHECK
emilmont 1:fdd22bb7aa52 87 /* Check for matrix mismatch */
emilmont 1:fdd22bb7aa52 88 if((pSrc->numRows != pDst->numRows) || (pSrc->numCols != pDst->numCols))
emilmont 1:fdd22bb7aa52 89 {
emilmont 1:fdd22bb7aa52 90 /* Set status as ARM_MATH_SIZE_MISMATCH */
emilmont 1:fdd22bb7aa52 91 status = ARM_MATH_SIZE_MISMATCH;
emilmont 1:fdd22bb7aa52 92 }
emilmont 1:fdd22bb7aa52 93 else
emilmont 1:fdd22bb7aa52 94 #endif // #ifdef ARM_MATH_MATRIX_CHECK
emilmont 1:fdd22bb7aa52 95 {
emilmont 1:fdd22bb7aa52 96 /* Total number of samples in the input matrix */
emilmont 1:fdd22bb7aa52 97 numSamples = (uint32_t) pSrc->numRows * pSrc->numCols;
emilmont 1:fdd22bb7aa52 98
emilmont 1:fdd22bb7aa52 99 #ifndef ARM_MATH_CM0
emilmont 1:fdd22bb7aa52 100
emilmont 1:fdd22bb7aa52 101 /* Run the below code for Cortex-M4 and Cortex-M3 */
emilmont 1:fdd22bb7aa52 102
emilmont 1:fdd22bb7aa52 103 /* Loop Unrolling */
emilmont 1:fdd22bb7aa52 104 blkCnt = numSamples >> 2u;
emilmont 1:fdd22bb7aa52 105
emilmont 1:fdd22bb7aa52 106 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
emilmont 1:fdd22bb7aa52 107 ** a second loop below computes the remaining 1 to 3 samples. */
emilmont 1:fdd22bb7aa52 108 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 109 {
emilmont 1:fdd22bb7aa52 110 /* C(m,n) = A(m,n) * k */
emilmont 1:fdd22bb7aa52 111 /* Read values from input */
emilmont 1:fdd22bb7aa52 112 in1 = *pIn;
emilmont 1:fdd22bb7aa52 113 in2 = *(pIn + 1);
emilmont 1:fdd22bb7aa52 114 in3 = *(pIn + 2);
emilmont 1:fdd22bb7aa52 115 in4 = *(pIn + 3);
emilmont 1:fdd22bb7aa52 116
emilmont 1:fdd22bb7aa52 117 /* multiply input with scaler value */
emilmont 1:fdd22bb7aa52 118 in1 = ((q63_t) in1 * scaleFract) >> 32;
emilmont 1:fdd22bb7aa52 119 in2 = ((q63_t) in2 * scaleFract) >> 32;
emilmont 1:fdd22bb7aa52 120 in3 = ((q63_t) in3 * scaleFract) >> 32;
emilmont 1:fdd22bb7aa52 121 in4 = ((q63_t) in4 * scaleFract) >> 32;
emilmont 1:fdd22bb7aa52 122
emilmont 1:fdd22bb7aa52 123 /* apply shifting */
emilmont 1:fdd22bb7aa52 124 out1 = in1 << totShift;
emilmont 1:fdd22bb7aa52 125 out2 = in2 << totShift;
emilmont 1:fdd22bb7aa52 126
emilmont 1:fdd22bb7aa52 127 /* saturate the results. */
emilmont 1:fdd22bb7aa52 128 if(in1 != (out1 >> totShift))
emilmont 1:fdd22bb7aa52 129 out1 = 0x7FFFFFFF ^ (in1 >> 31);
emilmont 1:fdd22bb7aa52 130
emilmont 1:fdd22bb7aa52 131 if(in2 != (out2 >> totShift))
emilmont 1:fdd22bb7aa52 132 out2 = 0x7FFFFFFF ^ (in2 >> 31);
emilmont 1:fdd22bb7aa52 133
emilmont 1:fdd22bb7aa52 134 out3 = in3 << totShift;
emilmont 1:fdd22bb7aa52 135 out4 = in4 << totShift;
emilmont 1:fdd22bb7aa52 136
emilmont 1:fdd22bb7aa52 137 *pOut = out1;
emilmont 1:fdd22bb7aa52 138 *(pOut + 1) = out2;
emilmont 1:fdd22bb7aa52 139
emilmont 1:fdd22bb7aa52 140 if(in3 != (out3 >> totShift))
emilmont 1:fdd22bb7aa52 141 out3 = 0x7FFFFFFF ^ (in3 >> 31);
emilmont 1:fdd22bb7aa52 142
emilmont 1:fdd22bb7aa52 143 if(in4 != (out4 >> totShift))
emilmont 1:fdd22bb7aa52 144 out4 = 0x7FFFFFFF ^ (in4 >> 31);
emilmont 1:fdd22bb7aa52 145
emilmont 1:fdd22bb7aa52 146
emilmont 1:fdd22bb7aa52 147 *(pOut + 2) = out3;
emilmont 1:fdd22bb7aa52 148 *(pOut + 3) = out4;
emilmont 1:fdd22bb7aa52 149
emilmont 1:fdd22bb7aa52 150 /* update pointers to process next sampels */
emilmont 1:fdd22bb7aa52 151 pIn += 4u;
emilmont 1:fdd22bb7aa52 152 pOut += 4u;
emilmont 1:fdd22bb7aa52 153
emilmont 1:fdd22bb7aa52 154
emilmont 1:fdd22bb7aa52 155 /* Decrement the numSamples loop counter */
emilmont 1:fdd22bb7aa52 156 blkCnt--;
emilmont 1:fdd22bb7aa52 157 }
emilmont 1:fdd22bb7aa52 158
emilmont 1:fdd22bb7aa52 159 /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
emilmont 1:fdd22bb7aa52 160 ** No loop unrolling is used. */
emilmont 1:fdd22bb7aa52 161 blkCnt = numSamples % 0x4u;
emilmont 1:fdd22bb7aa52 162
emilmont 1:fdd22bb7aa52 163 #else
emilmont 1:fdd22bb7aa52 164
emilmont 1:fdd22bb7aa52 165 /* Run the below code for Cortex-M0 */
emilmont 1:fdd22bb7aa52 166
emilmont 1:fdd22bb7aa52 167 /* Initialize blkCnt with number of samples */
emilmont 1:fdd22bb7aa52 168 blkCnt = numSamples;
emilmont 1:fdd22bb7aa52 169
emilmont 1:fdd22bb7aa52 170 #endif /* #ifndef ARM_MATH_CM0 */
emilmont 1:fdd22bb7aa52 171
emilmont 1:fdd22bb7aa52 172 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 173 {
emilmont 1:fdd22bb7aa52 174 /* C(m,n) = A(m,n) * k */
emilmont 1:fdd22bb7aa52 175 /* Scale, saturate and then store the results in the destination buffer. */
emilmont 1:fdd22bb7aa52 176 in1 = *pIn++;
emilmont 1:fdd22bb7aa52 177
emilmont 1:fdd22bb7aa52 178 in2 = ((q63_t) in1 * scaleFract) >> 32;
emilmont 1:fdd22bb7aa52 179
emilmont 1:fdd22bb7aa52 180 out1 = in2 << totShift;
emilmont 1:fdd22bb7aa52 181
emilmont 1:fdd22bb7aa52 182 if(in2 != (out1 >> totShift))
emilmont 1:fdd22bb7aa52 183 out1 = 0x7FFFFFFF ^ (in2 >> 31);
emilmont 1:fdd22bb7aa52 184
emilmont 1:fdd22bb7aa52 185 *pOut++ = out1;
emilmont 1:fdd22bb7aa52 186
emilmont 1:fdd22bb7aa52 187 /* Decrement the numSamples loop counter */
emilmont 1:fdd22bb7aa52 188 blkCnt--;
emilmont 1:fdd22bb7aa52 189 }
emilmont 1:fdd22bb7aa52 190
emilmont 1:fdd22bb7aa52 191 /* Set status as ARM_MATH_SUCCESS */
emilmont 1:fdd22bb7aa52 192 status = ARM_MATH_SUCCESS;
emilmont 1:fdd22bb7aa52 193 }
emilmont 1:fdd22bb7aa52 194
emilmont 1:fdd22bb7aa52 195 /* Return to application */
emilmont 1:fdd22bb7aa52 196 return (status);
emilmont 1:fdd22bb7aa52 197 }
emilmont 1:fdd22bb7aa52 198
emilmont 1:fdd22bb7aa52 199 /**
emilmont 1:fdd22bb7aa52 200 * @} end of MatrixScale group
emilmont 1:fdd22bb7aa52 201 */