mbed-os 6.10 versione
Diff: cmsis_dsp/BasicMathFunctions/arm_sub_f32.c
- Revision:
- 1:fdd22bb7aa52
- Child:
- 2:da51fb522205
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/BasicMathFunctions/arm_sub_f32.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,145 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_sub_f32.c +* +* Description: Floating-point vector 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 0.0.7 2010/06/10 +* Misra-C changes done +* ---------------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupMath + */ + +/** + * @defgroup BasicSub Vector Subtraction + * + * Element-by-element subtraction of two vectors. + * + * <pre> + * pDst[n] = pSrcA[n] - pSrcB[n], 0 <= n < blockSize. + * </pre> + * + * There are separate functions for floating-point, Q7, Q15, and Q31 data types. + */ + +/** + * @addtogroup BasicSub + * @{ + */ + + +/** + * @brief Floating-point vector subtraction. + * @param[in] *pSrcA points to the first input vector + * @param[in] *pSrcB points to the second input vector + * @param[out] *pDst points to the output vector + * @param[in] blockSize number of samples in each vector + * @return none. + */ + +void arm_sub_f32( + float32_t * pSrcA, + float32_t * pSrcB, + float32_t * pDst, + uint32_t blockSize) +{ + uint32_t blkCnt; /* loop counter */ + +#ifndef ARM_MATH_CM0 + +/* Run the below code for Cortex-M4 and Cortex-M3 */ + float32_t inA1, inA2, inA3, inA4; /* temporary variables */ + float32_t inB1, inB2, inB3, inB4; /* temporary variables */ + + /*loop Unrolling */ + blkCnt = blockSize >> 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 = A - B */ + /* Subtract and then store the results in the destination buffer. */ + /* Read 4 input samples from sourceA and sourceB */ + inA1 = *pSrcA; + inB1 = *pSrcB; + inA2 = *(pSrcA + 1); + inB2 = *(pSrcB + 1); + inA3 = *(pSrcA + 2); + inB3 = *(pSrcB + 2); + inA4 = *(pSrcA + 3); + inB4 = *(pSrcB + 3); + + /* dst = srcA - srcB */ + /* subtract and store the result */ + *pDst = inA1 - inB1; + *(pDst + 1) = inA2 - inB2; + *(pDst + 2) = inA3 - inB3; + *(pDst + 3) = inA4 - inB4; + + + /* Update pointers to process next sampels */ + pSrcA += 4u; + pSrcB += 4u; + pDst += 4u; + + /* 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 = blockSize % 0x4u; + +#else + + /* Run the below code for Cortex-M0 */ + + /* Initialize blkCnt with number of samples */ + blkCnt = blockSize; + +#endif /* #ifndef ARM_MATH_CM0 */ + + while(blkCnt > 0u) + { + /* C = A - B */ + /* Subtract and then store the results in the destination buffer. */ + *pDst++ = (*pSrcA++) - (*pSrcB++); + + /* Decrement the loop counter */ + blkCnt--; + } +} + +/** + * @} end of BasicSub group + */