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Diffstat (limited to 'Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_f16.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_f16.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_f16.c b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_f16.c new file mode 100644 index 0000000..b5017f1 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_max_f16.c @@ -0,0 +1,246 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_max_f16.c + * Description: Maximum value of a floating-point 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_f16.h" + +#if defined(ARM_FLOAT16_SUPPORTED) + +#if (defined(ARM_MATH_NEON) || defined(ARM_MATH_MVEF)) && !defined(ARM_MATH_AUTOVECTORIZE) +#include <limits.h> +#endif + +/** + @ingroup groupStats + */ + + +/** + @addtogroup Max + @{ + */ + +/** + @brief Maximum value of a floating-point 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_MVE_FLOAT16) && !defined(ARM_MATH_AUTOVECTORIZE) + +void arm_max_f16( + const float16_t * pSrc, + uint32_t blockSize, + float16_t * pResult, + uint32_t * pIndex) +{ + int32_t blkCnt; + f16x8_t vecSrc; + f16x8_t curExtremValVec = vdupq_n_f16(F16_MIN); + float16_t maxValue = F16_MIN; + uint32_t idx = blockSize; + uint16x8_t indexVec; + uint16x8_t curExtremIdxVec; + uint32_t curIdx = 0; + mve_pred16_t p0; + float16_t tmp; + + + indexVec = vidupq_wb_u16(&curIdx, 1); + curExtremIdxVec = vdupq_n_u16(0); + + /* Compute 4 outputs at a time */ + blkCnt = blockSize >> 3; + while (blkCnt > 0) + { + vecSrc = vldrhq_f16(pSrc); + /* + * Get current max per lane and current index per lane + * when a max is selected + */ + p0 = vcmpgeq(vecSrc, curExtremValVec); + curExtremValVec = vpselq(vecSrc, curExtremValVec, p0); + curExtremIdxVec = vpselq(indexVec, curExtremIdxVec, p0); + + indexVec = vidupq_wb_u16(&curIdx, 1); + + pSrc += 8; + /* Decrement the loop counter */ + blkCnt--; + } + + + /* + * Get max value across the vector + */ + maxValue = vmaxnmvq(maxValue, curExtremValVec); + /* + * set index for lower values to max possible index + */ + p0 = vcmpgeq(curExtremValVec, maxValue); + indexVec = vpselq(curExtremIdxVec, vdupq_n_u16(blockSize), p0); + /* + * Get min index which is thus for a max value + */ + idx = vminvq(idx, indexVec); + + /* Tail */ + blkCnt = blockSize & 7; + + while (blkCnt > 0) + { + /* Initialize tmp to the next consecutive values one by one */ + tmp = *pSrc++; + + /* compare for the maximum value */ + if ((_Float16)maxValue < (_Float16)tmp) + { + /* Update the maximum value and it's index */ + maxValue = tmp; + idx = blockSize - blkCnt; + } + + /* Decrement loop counter */ + blkCnt--; + } + + /* + * Save result + */ + *pIndex = idx; + *pResult = maxValue; +} + +#else +void arm_max_f16( + const float16_t * pSrc, + uint32_t blockSize, + float16_t * pResult, + uint32_t * pIndex) +{ + float16_t maxVal, out; /* Temporary variables to store the output value. */ + uint32_t blkCnt, outIndex; /* Loop counter */ + +#if defined (ARM_MATH_LOOPUNROLL) && !defined(ARM_MATH_AUTOVECTORIZE) + 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) && !defined(ARM_MATH_AUTOVECTORIZE) + /* 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 ((_Float16)out < (_Float16)maxVal) + { + /* Update the maximum value and it's index */ + out = maxVal; + outIndex = index + 1U; + } + + maxVal = *pSrc++; + if ((_Float16)out < (_Float16)maxVal) + { + out = maxVal; + outIndex = index + 2U; + } + + maxVal = *pSrc++; + if ((_Float16)out < (_Float16)maxVal) + { + out = maxVal; + outIndex = index + 3U; + } + + maxVal = *pSrc++; + if ((_Float16)out < (_Float16)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 ((_Float16)out < (_Float16)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_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */ + +/** + @} end of Max group + */ + +#endif /* #if defined(ARM_FLOAT16_SUPPORTED) */ + |