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Diff: cmsis_dsp/MatrixFunctions/arm_mat_sub_q15.c
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diff -r 83d0537c7d84 -r fdd22bb7aa52 cmsis_dsp/MatrixFunctions/arm_mat_sub_q15.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/MatrixFunctions/arm_mat_sub_q15.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,158 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_mat_sub_q15.c +* +* Description: Q15 Matrix subtraction +* +* 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 MatrixSub + * @{ + */ + +/** + * @brief Q15 matrix subtraction. + * @param[in] *pSrcA points to the first input matrix structure + * @param[in] *pSrcB points to the second input matrix structure + * @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. + * + * <b>Scaling and Overflow Behavior:</b> + * \par + * The function uses saturating arithmetic. + * Results outside of the allowable Q15 range [0x8000 0x7FFF] will be saturated. + */ + +arm_status arm_mat_sub_q15( + const arm_matrix_instance_q15 * pSrcA, + const arm_matrix_instance_q15 * pSrcB, + arm_matrix_instance_q15 * pDst) +{ + q15_t *pInA = pSrcA->pData; /* input data matrix pointer A */ + q15_t *pInB = pSrcB->pData; /* input data matrix pointer B */ + q15_t *pOut = pDst->pData; /* output data matrix pointer */ + uint32_t numSamples; /* total number of elements in the matrix */ + uint32_t blkCnt; /* loop counters */ + arm_status status; /* status of matrix subtraction */ + + +#ifdef ARM_MATH_MATRIX_CHECK + + + /* Check for matrix mismatch condition */ + if((pSrcA->numRows != pSrcB->numRows) || + (pSrcA->numCols != pSrcB->numCols) || + (pSrcA->numRows != pDst->numRows) || (pSrcA->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) pSrcA->numRows * pSrcA->numCols; + +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + + /* Apply 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) - B(m,n) */ + /* Subtract, Saturate and then store the results in the destination buffer. */ + *__SIMD32(pOut)++ = __QSUB16(*__SIMD32(pInA)++, *__SIMD32(pInB)++); + *__SIMD32(pOut)++ = __QSUB16(*__SIMD32(pInA)++, *__SIMD32(pInB)++); + + /* Decrement the loop counter */ + blkCnt--; + } + + /* If the blockSize is not a multiple of 4, compute any remaining output samples here. + ** No loop unrolling is used. */ + blkCnt = numSamples % 0x4u; + + while(blkCnt > 0u) + { + /* C(m,n) = A(m,n) - B(m,n) */ + /* Subtract and then store the results in the destination buffer. */ + *pOut++ = (q15_t) __QSUB16(*pInA++, *pInB++); + + /* Decrement the loop counter */ + blkCnt--; + } + +#else + + /* Run the below code for Cortex-M0 */ + + /* Initialize blkCnt with number of samples */ + blkCnt = numSamples; + + while(blkCnt > 0u) + { + /* C(m,n) = A(m,n) - B(m,n) */ + /* Subtract and then store the results in the destination buffer. */ + *pOut++ = (q15_t) __SSAT(((q31_t) * pInA++ - *pInB++), 16); + + /* Decrement the loop counter */ + blkCnt--; + } + +#endif /* #ifndef ARM_MATH_CM0 */ + + /* Set status as ARM_MATH_SUCCESS */ + status = ARM_MATH_SUCCESS; + } + + /* Return to application */ + return (status); +} + +/** + * @} end of MatrixSub group + */