CMSIS DSP Lib
Fork of mbed-dsp by
Diff: cmsis_dsp/MatrixFunctions/arm_mat_scale_q31.c
- Revision:
- 1:fdd22bb7aa52
- Child:
- 2:da51fb522205
diff -r 83d0537c7d84 -r fdd22bb7aa52 cmsis_dsp/MatrixFunctions/arm_mat_scale_q31.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/MatrixFunctions/arm_mat_scale_q31.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,201 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_mat_scale_q31.c +* +* Description: Multiplies a Q31 matrix by a scalar. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* Version 1.0.10 2011/7/15 +* Big Endian support added and Merged M0 and M3/M4 Source code. +* +* Version 1.0.3 2010/11/29 +* Re-organized the CMSIS folders and updated documentation. +* +* Version 1.0.2 2010/11/11 +* Documentation updated. +* +* Version 1.0.1 2010/10/05 +* Production release and review comments incorporated. +* +* Version 1.0.0 2010/09/20 +* Production release and review comments incorporated. +* +* Version 0.0.5 2010/04/26 +* incorporated review comments and updated with latest CMSIS layer +* +* Version 0.0.3 2010/03/10 +* Initial version +* -------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupMatrix + */ + +/** + * @addtogroup MatrixScale + * @{ + */ + +/** + * @brief Q31 matrix scaling. + * @param[in] *pSrc points to input matrix + * @param[in] scaleFract fractional portion of the scale factor + * @param[in] shift number of bits to shift the result by + * @param[out] *pDst points to output matrix structure + * @return The function returns either + * <code>ARM_MATH_SIZE_MISMATCH</code> or <code>ARM_MATH_SUCCESS</code> based on the outcome of size checking. + * + * @details + * <b>Scaling and Overflow Behavior:</b> + * \par + * The input data <code>*pSrc</code> and <code>scaleFract</code> are in 1.31 format. + * These are multiplied to yield a 2.62 intermediate result and this is shifted with saturation to 1.31 format. + */ + +arm_status arm_mat_scale_q31( + const arm_matrix_instance_q31 * pSrc, + q31_t scaleFract, + int32_t shift, + arm_matrix_instance_q31 * pDst) +{ + q31_t *pIn = pSrc->pData; /* input data matrix pointer */ + q31_t *pOut = pDst->pData; /* output data matrix pointer */ + uint32_t numSamples; /* total number of elements in the matrix */ + int32_t totShift = shift + 1; /* shift to apply after scaling */ + uint32_t blkCnt; /* loop counters */ + arm_status status; /* status of matrix scaling */ + q31_t in1, in2, out1; /* temporary variabels */ + +#ifndef ARM_MATH_CM0 + + q31_t in3, in4, out2, out3, out4; /* temporary variables */ + +#endif // #ifndef ARM_MAT_CM0 + +#ifdef ARM_MATH_MATRIX_CHECK + /* Check for matrix mismatch */ + if((pSrc->numRows != pDst->numRows) || (pSrc->numCols != pDst->numCols)) + { + /* Set status as ARM_MATH_SIZE_MISMATCH */ + status = ARM_MATH_SIZE_MISMATCH; + } + else +#endif // #ifdef ARM_MATH_MATRIX_CHECK + { + /* Total number of samples in the input matrix */ + numSamples = (uint32_t) pSrc->numRows * pSrc->numCols; + +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + + /* Loop Unrolling */ + blkCnt = numSamples >> 2u; + + /* First part of the processing with loop unrolling. Compute 4 outputs at a time. + ** a second loop below computes the remaining 1 to 3 samples. */ + while(blkCnt > 0u) + { + /* C(m,n) = A(m,n) * k */ + /* Read values from input */ + in1 = *pIn; + in2 = *(pIn + 1); + in3 = *(pIn + 2); + in4 = *(pIn + 3); + + /* multiply input with scaler value */ + in1 = ((q63_t) in1 * scaleFract) >> 32; + in2 = ((q63_t) in2 * scaleFract) >> 32; + in3 = ((q63_t) in3 * scaleFract) >> 32; + in4 = ((q63_t) in4 * scaleFract) >> 32; + + /* apply shifting */ + out1 = in1 << totShift; + out2 = in2 << totShift; + + /* saturate the results. */ + if(in1 != (out1 >> totShift)) + out1 = 0x7FFFFFFF ^ (in1 >> 31); + + if(in2 != (out2 >> totShift)) + out2 = 0x7FFFFFFF ^ (in2 >> 31); + + out3 = in3 << totShift; + out4 = in4 << totShift; + + *pOut = out1; + *(pOut + 1) = out2; + + if(in3 != (out3 >> totShift)) + out3 = 0x7FFFFFFF ^ (in3 >> 31); + + if(in4 != (out4 >> totShift)) + out4 = 0x7FFFFFFF ^ (in4 >> 31); + + + *(pOut + 2) = out3; + *(pOut + 3) = out4; + + /* update pointers to process next sampels */ + pIn += 4u; + pOut += 4u; + + + /* Decrement the numSamples loop counter */ + blkCnt--; + } + + /* If the numSamples is not a multiple of 4, compute any remaining output samples here. + ** No loop unrolling is used. */ + blkCnt = numSamples % 0x4u; + +#else + + /* Run the below code for Cortex-M0 */ + + /* Initialize blkCnt with number of samples */ + blkCnt = numSamples; + +#endif /* #ifndef ARM_MATH_CM0 */ + + while(blkCnt > 0u) + { + /* C(m,n) = A(m,n) * k */ + /* Scale, saturate and then store the results in the destination buffer. */ + in1 = *pIn++; + + in2 = ((q63_t) in1 * scaleFract) >> 32; + + out1 = in2 << totShift; + + if(in2 != (out1 >> totShift)) + out1 = 0x7FFFFFFF ^ (in2 >> 31); + + *pOut++ = out1; + + /* Decrement the numSamples loop counter */ + blkCnt--; + } + + /* Set status as ARM_MATH_SUCCESS */ + status = ARM_MATH_SUCCESS; + } + + /* Return to application */ + return (status); +} + +/** + * @} end of MatrixScale group + */