diff options
Diffstat (limited to 'DSP/Source/BasicMathFunctions/arm_negate_q7.c')
| -rw-r--r-- | DSP/Source/BasicMathFunctions/arm_negate_q7.c | 101 |
1 files changed, 57 insertions, 44 deletions
diff --git a/DSP/Source/BasicMathFunctions/arm_negate_q7.c b/DSP/Source/BasicMathFunctions/arm_negate_q7.c index d72c317..40a373e 100644 --- a/DSP/Source/BasicMathFunctions/arm_negate_q7.c +++ b/DSP/Source/BasicMathFunctions/arm_negate_q7.c @@ -3,13 +3,13 @@ * Title: arm_negate_q7.c * Description: Negates Q7 vectors * - * $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 * @@ -29,85 +29,98 @@ #include "arm_math.h" /** - * @ingroup groupMath + @ingroup groupMath */ /** - * @addtogroup negate - * @{ + @addtogroup BasicNegate + @{ */ /** - * @brief Negates the elements of a Q7 vector. - * @param[in] *pSrc points to the input vector - * @param[out] *pDst points to the output vector - * @param[in] blockSize number of samples in the vector - * @return none. - * - * <b>Scaling and Overflow Behavior:</b> - * \par - * The function uses saturating arithmetic. - * The Q7 value -1 (0x80) will be saturated to the maximum allowable positive value 0x7F. + @brief Negates the elements of a Q7 vector. + @param[in] pSrc points to the 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. + The Q7 value -1 (0x80) is saturated to the maximum allowable positive value 0x7F. */ void arm_negate_q7( - q7_t * pSrc, - q7_t * pDst, - uint32_t blockSize) + const q7_t * pSrc, + q7_t * pDst, + uint32_t blockSize) { - uint32_t blkCnt; /* loop counter */ - q7_t in; - -#if defined (ARM_MATH_DSP) + uint32_t blkCnt; /* Loop counter */ + q7_t in; /* Temporary input variable */ -/* Run the below code for Cortex-M4 and Cortex-M3 */ - q31_t input; /* Input values1-4 */ - q31_t zero = 0x00000000; +#if defined (ARM_MATH_LOOPUNROLL) +#if defined (ARM_MATH_DSP) + q31_t in1; /* Temporary input variable */ +#endif - /*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 */ - /* Read four inputs */ - input = *__SIMD32(pSrc)++; - /* Store the Negated results in the destination buffer in a single cycle by packing the results */ - *__SIMD32(pDst)++ = __QSUB8(zero, input); +#if defined (ARM_MATH_DSP) + /* Negate and store result in destination buffer (4 samples at a time). */ + in1 = read_q7x4_ia ((q7_t **) &pSrc); + write_q7x4_ia (&pDst, __QSUB8(0, in1)); +#else + in = *pSrc++; + *pDst++ = (in == (q7_t) 0x80) ? (q7_t) 0x7f : -in; + + in = *pSrc++; + *pDst++ = (in == (q7_t) 0x80) ? (q7_t) 0x7f : -in; + + in = *pSrc++; + *pDst++ = (in == (q7_t) 0x80) ? (q7_t) 0x7f : -in; - /* Decrement the loop counter */ + in = *pSrc++; + *pDst++ = (in == (q7_t) 0x80) ? (q7_t) 0x7f : -in; +#endif + + /* Decrement loop counter */ blkCnt--; } - /* If the blockSize is not a multiple of 4, compute any remaining output samples here. - ** No loop unrolling is used. */ + /* Loop unrolling: Compute remaining outputs */ blkCnt = blockSize % 0x4U; #else - /* Run the below code for Cortex-M0 */ - /* Initialize blkCnt with number of samples */ blkCnt = blockSize; -#endif /* #if defined (ARM_MATH_DSP) */ +#endif /* #if defined (ARM_MATH_LOOPUNROLL) */ while (blkCnt > 0U) { /* C = -A */ - /* Negate and then store the results in the destination buffer. */ \ - in = *pSrc++; - *pDst++ = (in == (q7_t) 0x80) ? 0x7f : -in; - /* Decrement the loop counter */ + /* Negate and store result in destination buffer. */ + in = *pSrc++; + +#if defined (ARM_MATH_DSP) + *pDst++ = (q7_t) __QSUB(0, in); +#else + *pDst++ = (in == (q7_t) 0x80) ? (q7_t) 0x7f : -in; +#endif + + /* Decrement loop counter */ blkCnt--; } + } /** - * @} end of negate group + @} end of BasicNegate group */ |