| /* ---------------------------------------------------------------------- |
| * Project: CMSIS DSP Library |
| * Title: arm_abs_q7.c |
| * Description: Q7 vector absolute value |
| * |
| * $Date: 18. March 2019 |
| * $Revision: V1.6.0 |
| * |
| * Target Processor: Cortex-M cores |
| * -------------------------------------------------------------------- */ |
| /* |
| * Copyright (C) 2010-2019 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 "arm_math.h" |
| |
| /** |
| @ingroup groupMath |
| */ |
| |
| /** |
| @addtogroup BasicAbs |
| @{ |
| */ |
| |
| /** |
| @brief Q7 vector absolute value. |
| @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 Conditions for optimum performance |
| Input and output buffers should be aligned by 32-bit |
| @par Scaling and Overflow Behavior |
| The function uses saturating arithmetic. |
| The Q7 value -1 (0x80) will be saturated to the maximum allowable positive value 0x7F. |
| */ |
| |
| #if defined(ARM_MATH_MVEI) |
| |
| #include "arm_helium_utils.h" |
| |
| void arm_abs_q7( |
| const q7_t * pSrc, |
| q7_t * pDst, |
| uint32_t blockSize) |
| { |
| uint32_t blkCnt; /* loop counters */ |
| q7x16_t vecSrc; |
| |
| /* Compute 16 outputs at a time */ |
| blkCnt = blockSize >> 4; |
| while (blkCnt > 0U) |
| { |
| /* |
| * C = |A| |
| * Calculate absolute and then store the results in the destination buffer. |
| */ |
| vecSrc = vld1q(pSrc); |
| vst1q(pDst, vqabsq(vecSrc)); |
| /* |
| * Decrement the blockSize loop counter |
| */ |
| blkCnt--; |
| /* |
| * advance vector source and destination pointers |
| */ |
| pSrc += 16; |
| pDst += 16; |
| } |
| /* |
| * tail |
| */ |
| blkCnt = blockSize & 0xF; |
| if (blkCnt > 0U) |
| { |
| mve_pred16_t p0 = vctp8q(blkCnt); |
| vecSrc = vld1q(pSrc); |
| vstrbq_p(pDst, vqabsq(vecSrc), p0); |
| } |
| } |
| |
| #else |
| void arm_abs_q7( |
| const q7_t * pSrc, |
| q7_t * pDst, |
| uint32_t blockSize) |
| { |
| uint32_t blkCnt; /* Loop counter */ |
| q7_t in; /* Temporary input variable */ |
| |
| #if defined (ARM_MATH_LOOPUNROLL) |
| |
| /* Loop unrolling: Compute 4 outputs at a time */ |
| blkCnt = blockSize >> 2U; |
| |
| while (blkCnt > 0U) |
| { |
| /* C = |A| */ |
| |
| /* Calculate absolute of input (if -1 then saturated to 0x7f) and store result in destination buffer. */ |
| in = *pSrc++; |
| #if defined (ARM_MATH_DSP) |
| *pDst++ = (in > 0) ? in : (q7_t)__QSUB8(0, in); |
| #else |
| *pDst++ = (in > 0) ? in : ((in == (q7_t) 0x80) ? (q7_t) 0x7f : -in); |
| #endif |
| |
| in = *pSrc++; |
| #if defined (ARM_MATH_DSP) |
| *pDst++ = (in > 0) ? in : (q7_t)__QSUB8(0, in); |
| #else |
| *pDst++ = (in > 0) ? in : ((in == (q7_t) 0x80) ? (q7_t) 0x7f : -in); |
| #endif |
| |
| in = *pSrc++; |
| #if defined (ARM_MATH_DSP) |
| *pDst++ = (in > 0) ? in : (q7_t)__QSUB8(0, in); |
| #else |
| *pDst++ = (in > 0) ? in : ((in == (q7_t) 0x80) ? (q7_t) 0x7f : -in); |
| #endif |
| |
| in = *pSrc++; |
| #if defined (ARM_MATH_DSP) |
| *pDst++ = (in > 0) ? in : (q7_t)__QSUB8(0, in); |
| #else |
| *pDst++ = (in > 0) ? in : ((in == (q7_t) 0x80) ? (q7_t) 0x7f : -in); |
| #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| */ |
| |
| /* Calculate absolute of input (if -1 then saturated to 0x7f) and store result in destination buffer. */ |
| in = *pSrc++; |
| #if defined (ARM_MATH_DSP) |
| *pDst++ = (in > 0) ? in : (q7_t) __QSUB8(0, in); |
| #else |
| *pDst++ = (in > 0) ? in : ((in == (q7_t) 0x80) ? (q7_t) 0x7f : -in); |
| #endif |
| |
| /* Decrement loop counter */ |
| blkCnt--; |
| } |
| |
| } |
| #endif /* defined(ARM_MATH_MVEI) */ |
| |
| /** |
| @} end of BasicAbs group |
| */ |