diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q15.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q15.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q15.c b/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q15.c new file mode 100644 index 0000000..575bd9f --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/BasicMathFunctions/arm_sub_q15.c @@ -0,0 +1,178 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_sub_q15.c + * Description: Q15 vector subtraction + * + * $Date: 23 April 2021 + * $Revision: V1.9.0 + * + * Target Processor: Cortex-M and Cortex-A cores + * -------------------------------------------------------------------- */ +/* + * Copyright (C) 2010-2021 ARM Limited or its affiliates. All rights reserved. + * + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed under the Apache License, Version 2.0 (the License); you may + * not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an AS IS BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "dsp/basic_math_functions.h" + +/** + @ingroup groupMath + */ + +/** + @addtogroup BasicSub + @{ + */ + +/** + @brief Q15 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 Q15 range [0x8000 0x7FFF] are saturated. + */ + +#if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE) + +#include "arm_helium_utils.h" + +void arm_sub_q15( + const q15_t * pSrcA, + const q15_t * pSrcB, + q15_t * pDst, + uint32_t blockSize) +{ + uint32_t blkCnt; /* loop counters */ + q15x8_t vecA; + q15x8_t vecB; + + /* Compute 8 outputs at a time */ + blkCnt = blockSize >> 3; + while (blkCnt > 0U) + { + /* + * C = A - B + * Subtract and then store the results in the destination buffer. + */ + vecA = vld1q(pSrcA); + vecB = vld1q(pSrcB); + vst1q(pDst, vqsubq(vecA, vecB)); + /* + * Decrement the blockSize loop counter + */ + blkCnt--; + /* + * advance vector source and destination pointers + */ + pSrcA += 8; + pSrcB += 8; + pDst += 8; + } + /* + * tail + */ + blkCnt = blockSize & 7; + if (blkCnt > 0U) + { + mve_pred16_t p0 = vctp16q(blkCnt); + vecA = vld1q(pSrcA); + vecB = vld1q(pSrcB); + vstrhq_p(pDst, vqsubq(vecA, vecB), p0); + } +} + + +#else +void arm_sub_q15( + const q15_t * pSrcA, + const q15_t * pSrcB, + q15_t * pDst, + uint32_t blockSize) +{ + uint32_t blkCnt; /* Loop counter */ + +#if defined (ARM_MATH_LOOPUNROLL) + +#if defined (ARM_MATH_DSP) + q31_t inA1, inA2; + q31_t inB1, inB2; +#endif + + /* Loop unrolling: Compute 4 outputs at a time */ + blkCnt = blockSize >> 2U; + + while (blkCnt > 0U) + { + /* C = A - B */ + +#if defined (ARM_MATH_DSP) + /* read 2 times 2 samples at a time from sourceA */ + inA1 = read_q15x2_ia (&pSrcA); + inA2 = read_q15x2_ia (&pSrcA); + /* read 2 times 2 samples at a time from sourceB */ + inB1 = read_q15x2_ia (&pSrcB); + inB2 = read_q15x2_ia (&pSrcB); + + /* Subtract and store 2 times 2 samples at a time */ + write_q15x2_ia (&pDst, __QSUB16(inA1, inB1)); + write_q15x2_ia (&pDst, __QSUB16(inA2, inB2)); +#else + *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ - *pSrcB++), 16); + *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ - *pSrcB++), 16); + *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ - *pSrcB++), 16); + *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ - *pSrcB++), 16); +#endif + + /* Decrement loop counter */ + blkCnt--; + } + + /* Loop unrolling: Compute remaining outputs */ + blkCnt = blockSize % 0x4U; + +#else + + /* Initialize blkCnt with number of samples */ + blkCnt = blockSize; + +#endif /* #if defined (ARM_MATH_LOOPUNROLL) */ + + while (blkCnt > 0U) + { + /* C = A - B */ + + /* Subtract and store result in destination buffer. */ +#if defined (ARM_MATH_DSP) + *pDst++ = (q15_t) __QSUB16(*pSrcA++, *pSrcB++); +#else + *pDst++ = (q15_t) __SSAT(((q31_t) *pSrcA++ - *pSrcB++), 16); +#endif + + /* Decrement loop counter */ + blkCnt--; + } + +} +#endif /* defined(ARM_MATH_MVEI) */ + +/** + @} end of BasicSub group + */ |