diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q31.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q31.c | 106 |
1 files changed, 40 insertions, 66 deletions
diff --git a/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q31.c b/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q31.c index 72b8597f4..bac1927bd 100644 --- a/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q31.c +++ b/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q31.c @@ -3,13 +3,13 @@ * Title: arm_sub_q31.c * Description: Q31 vector subtraction * - * $Date: 27. January 2017 - * $Revision: V.1.5.1 + * $Date: 18. March 2019 + * $Revision: V1.6.0 * * Target Processor: Cortex-M cores * -------------------------------------------------------------------- */ /* - * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved. + * Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved. * * SPDX-License-Identifier: Apache-2.0 * @@ -29,106 +29,80 @@ #include "arm_math.h" /** - * @ingroup groupMath + @ingroup groupMath */ /** - * @addtogroup BasicSub - * @{ + @addtogroup BasicSub + @{ */ /** - * @brief Q31 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. - * - * <b>Scaling and Overflow Behavior:</b> - * \par - * The function uses saturating arithmetic. - * Results outside of the allowable Q31 range [0x80000000 0x7FFFFFFF] will be saturated. + @brief Q31 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 + + @par Scaling and Overflow Behavior + The function uses saturating arithmetic. + Results outside of the allowable Q31 range [0x80000000 0x7FFFFFFF] are saturated. */ void arm_sub_q31( - q31_t * pSrcA, - q31_t * pSrcB, - q31_t * pDst, - uint32_t blockSize) + const q31_t * pSrcA, + const q31_t * pSrcB, + q31_t * pDst, + uint32_t blockSize) { - uint32_t blkCnt; /* loop counter */ - - -#if defined (ARM_MATH_DSP) + uint32_t blkCnt; /* Loop counter */ -/* Run the below code for Cortex-M4 and Cortex-M3 */ - q31_t inA1, inA2, inA3, inA4; - q31_t inB1, inB2, inB3, inB4; +#if defined (ARM_MATH_LOOPUNROLL) - /*loop Unrolling */ + /* Loop unrolling: Compute 4 outputs at a time */ 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. */ - inA1 = *pSrcA++; - inA2 = *pSrcA++; - inB1 = *pSrcB++; - inB2 = *pSrcB++; - - inA3 = *pSrcA++; - inA4 = *pSrcA++; - inB3 = *pSrcB++; - inB4 = *pSrcB++; - - *pDst++ = __QSUB(inA1, inB1); - *pDst++ = __QSUB(inA2, inB2); - *pDst++ = __QSUB(inA3, inB3); - *pDst++ = __QSUB(inA4, inB4); - - /* 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; + /* Subtract and store result in destination buffer. */ + *pDst++ = __QSUB(*pSrcA++, *pSrcB++); - while (blkCnt > 0U) - { - /* C = A - B */ - /* Subtract and then store the result in the destination buffer. */ *pDst++ = __QSUB(*pSrcA++, *pSrcB++); - /* Decrement the loop counter */ + *pDst++ = __QSUB(*pSrcA++, *pSrcB++); + + *pDst++ = __QSUB(*pSrcA++, *pSrcB++); + + /* Decrement loop counter */ blkCnt--; } -#else + /* Loop unrolling: Compute remaining outputs */ + blkCnt = blockSize % 0x4U; - /* Run the below code for Cortex-M0 */ +#else /* Initialize blkCnt with number of samples */ blkCnt = blockSize; +#endif /* #if defined (ARM_MATH_LOOPUNROLL) */ + while (blkCnt > 0U) { /* C = A - B */ - /* Subtract and then store the result in the destination buffer. */ - *pDst++ = (q31_t) clip_q63_to_q31((q63_t) * pSrcA++ - *pSrcB++); - /* Decrement the loop counter */ + /* Subtract and store result in destination buffer. */ + *pDst++ = __QSUB(*pSrcA++, *pSrcB++); + + /* Decrement loop counter */ blkCnt--; } -#endif /* #if defined (ARM_MATH_DSP) */ - } /** - * @} end of BasicSub group + @} end of BasicSub group */ |