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Diffstat (limited to 'Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_q7.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_q7.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_q7.c b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_q7.c new file mode 100644 index 0000000..5deae64 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_q7.c @@ -0,0 +1,256 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_max_q7.c + * Description: Maximum value of a Q7 vector + * + * $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/statistics_functions.h" + +/** + @ingroup groupStats + */ + +/** + @addtogroup Max + @{ + */ + +/** + @brief Maximum value of a Q7 vector. + @param[in] pSrc points to the input vector + @param[in] blockSize number of samples in input vector + @param[out] pResult maximum value returned here + @param[out] pIndex index of maximum value returned here + @return none + */ +#if defined(ARM_MATH_MVEI) && !defined(ARM_MATH_AUTOVECTORIZE) + +#include "arm_helium_utils.h" + +static void arm_small_blk_max_q7( + const q7_t * pSrc, + uint16_t blockSize, + q7_t * pResult, + uint32_t * pIndex) +{ + int32_t blkCnt; /* loop counters */ + q7x16_t extremValVec = vdupq_n_s8(Q7_MIN); + q7_t maxValue = Q7_MIN; + uint8x16_t indexVec; + uint8x16_t extremIdxVec; + mve_pred16_t p0; + uint8_t extremIdxArr[16]; + + indexVec = vidupq_u8(0U, 1); + + blkCnt = blockSize; + do { + mve_pred16_t p = vctp8q(blkCnt); + q7x16_t extremIdxVal = vld1q_z_s8(pSrc, p); + /* + * Get current max per lane and current index per lane + * when a max is selected + */ + p0 = vcmpgeq_m(extremIdxVal, extremValVec, p); + + extremValVec = vorrq_m(extremValVec, extremIdxVal, extremIdxVal, p0); + /* store per-lane extrema indexes */ + vst1q_p_u8(extremIdxArr, indexVec, p0); + + indexVec += 16; + pSrc += 16; + blkCnt -= 16; + } + while (blkCnt > 0); + + + /* Get max value across the vector */ + maxValue = vmaxvq(maxValue, extremValVec); + + /* set index for lower values to max possible index */ + p0 = vcmpgeq(extremValVec, maxValue); + extremIdxVec = vld1q_u8(extremIdxArr); + + indexVec = vpselq(extremIdxVec, vdupq_n_u8(blockSize - 1), p0); + *pIndex = vminvq_u8(blockSize - 1, indexVec); + *pResult = maxValue; +} + +void arm_max_q7( + const q7_t * pSrc, + uint32_t blockSize, + q7_t * pResult, + uint32_t * pIndex) +{ + int32_t totalSize = blockSize; + const uint16_t sub_blk_sz = UINT8_MAX + 1; + + if (totalSize <= sub_blk_sz) + { + arm_small_blk_max_q7(pSrc, blockSize, pResult, pIndex); + } + else + { + uint32_t curIdx = 0; + q7_t curBlkExtr = Q7_MIN; + uint32_t curBlkPos = 0; + uint32_t curBlkIdx = 0; + /* + * process blocks of 255 elts + */ + while (totalSize >= sub_blk_sz) + { + const q7_t *curSrc = pSrc; + + arm_small_blk_max_q7(curSrc, sub_blk_sz, pResult, pIndex); + if (*pResult > curBlkExtr) + { + /* + * update partial extrema + */ + curBlkExtr = *pResult; + curBlkPos = *pIndex; + curBlkIdx = curIdx; + } + curIdx++; + pSrc += sub_blk_sz; + totalSize -= sub_blk_sz; + } + /* + * remainder + */ + arm_small_blk_max_q7(pSrc, totalSize, pResult, pIndex); + if (*pResult > curBlkExtr) + { + curBlkExtr = *pResult; + curBlkPos = *pIndex; + curBlkIdx = curIdx; + } + *pIndex = curBlkIdx * sub_blk_sz + curBlkPos; + *pResult = curBlkExtr; + } +} +#else +void arm_max_q7( + const q7_t * pSrc, + uint32_t blockSize, + q7_t * pResult, + uint32_t * pIndex) +{ + q7_t maxVal, out; /* Temporary variables to store the output value. */ + uint32_t blkCnt, outIndex; /* Loop counter */ + +#if defined (ARM_MATH_LOOPUNROLL) + uint32_t index; /* index of maximum value */ +#endif + + /* Initialise index value to zero. */ + outIndex = 0U; + /* Load first input value that act as reference value for comparision */ + out = *pSrc++; + +#if defined (ARM_MATH_LOOPUNROLL) + /* Initialise index of maximum value. */ + index = 0U; + + /* Loop unrolling: Compute 4 outputs at a time */ + blkCnt = (blockSize - 1U) >> 2U; + + while (blkCnt > 0U) + { + /* Initialize maxVal to next consecutive values one by one */ + maxVal = *pSrc++; + + /* compare for the maximum value */ + if (out < maxVal) + { + /* Update the maximum value and it's index */ + out = maxVal; + outIndex = index + 1U; + } + + maxVal = *pSrc++; + if (out < maxVal) + { + out = maxVal; + outIndex = index + 2U; + } + + maxVal = *pSrc++; + if (out < maxVal) + { + out = maxVal; + outIndex = index + 3U; + } + + maxVal = *pSrc++; + if (out < maxVal) + { + out = maxVal; + outIndex = index + 4U; + } + + index += 4U; + + /* Decrement loop counter */ + blkCnt--; + } + + /* Loop unrolling: Compute remaining outputs */ + blkCnt = (blockSize - 1U) % 4U; + +#else + + /* Initialize blkCnt with number of samples */ + blkCnt = (blockSize - 1U); + +#endif /* #if defined (ARM_MATH_LOOPUNROLL) */ + + while (blkCnt > 0U) + { + /* Initialize maxVal to the next consecutive values one by one */ + maxVal = *pSrc++; + + /* compare for the maximum value */ + if (out < maxVal) + { + /* Update the maximum value and it's index */ + out = maxVal; + outIndex = blockSize - blkCnt; + } + + /* Decrement loop counter */ + blkCnt--; + } + + /* Store the maximum value and it's index into destination pointers */ + *pResult = out; + *pIndex = outIndex; +} +#endif /* defined(ARM_MATH_MVEI) */ + +/** + @} end of Max group + */ |