diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f16.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f16.c | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f16.c b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f16.c new file mode 100644 index 0000000..0e3ade5 --- /dev/null +++ b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f16.c @@ -0,0 +1,209 @@ +/* ---------------------------------------------------------------------- + * Project: CMSIS DSP Library + * Title: arm_var_f16.c + * Description: Variance of the elements 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) + + +/** + @ingroup groupStats + */ + + +/** + @addtogroup variance + @{ + */ + +/** + @brief Variance of the elements 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 variance value returned here + @return none + */ +#if defined(ARM_MATH_MVE_FLOAT16) && !defined(ARM_MATH_AUTOVECTORIZE) + +#include "arm_helium_utils.h" + + +void arm_var_f16( + const float16_t * pSrc, + uint32_t blockSize, + float16_t * pResult) +{ + int32_t blkCnt; /* loop counters */ + f16x8_t vecSrc; + f16x8_t sumVec = vdupq_n_f16(0.0f16); + float16_t fMean; + + if (blockSize <= 1U) { + *pResult = 0; + return; + } + + + arm_mean_f16(pSrc, blockSize, &fMean); + + blkCnt = blockSize; + do { + mve_pred16_t p = vctp16q(blkCnt); + + vecSrc = vldrhq_z_f16((float16_t const *) pSrc, p); + /* + * sum lanes + */ + vecSrc = vsubq_m(vuninitializedq_f16(), vecSrc, fMean, p); + sumVec = vfmaq_m(sumVec, vecSrc, vecSrc, p); + + blkCnt -= 8; + pSrc += 8; + } + while (blkCnt > 0); + + /* Variance */ + *pResult = (_Float16)vecAddAcrossF16Mve(sumVec) / (_Float16) (blockSize - 1.0f16); +} +#else + +void arm_var_f16( + const float16_t * pSrc, + uint32_t blockSize, + float16_t * pResult) +{ + uint32_t blkCnt; /* Loop counter */ + _Float16 sum = 0.0f; /* Temporary result storage */ + _Float16 fSum = 0.0f; + _Float16 fMean, fValue; + const float16_t * pInput = pSrc; + + if (blockSize <= 1U) + { + *pResult = 0; + return; + } + +#if defined (ARM_MATH_LOOPUNROLL) && !defined(ARM_MATH_AUTOVECTORIZE) + + /* Loop unrolling: Compute 4 outputs at a time */ + blkCnt = blockSize >> 2U; + + while (blkCnt > 0U) + { + /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */ + + sum += (_Float16)*pInput++; + sum += (_Float16)*pInput++; + sum += (_Float16)*pInput++; + sum += (_Float16)*pInput++; + + + /* 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[0] + A[1] + A[2] + ... + A[blockSize-1]) */ + + sum += (_Float16)*pInput++; + + /* Decrement loop counter */ + blkCnt--; + } + + /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize */ + fMean = (_Float16)sum / (_Float16) blockSize; + + pInput = pSrc; + +#if defined (ARM_MATH_LOOPUNROLL) && !defined(ARM_MATH_AUTOVECTORIZE) + + /* Loop unrolling: Compute 4 outputs at a time */ + blkCnt = blockSize >> 2U; + + while (blkCnt > 0U) + { + fValue = (_Float16)*pInput++ - (_Float16)fMean; + fSum += (_Float16)fValue * (_Float16)fValue; + + fValue = (_Float16)*pInput++ - (_Float16)fMean; + fSum += (_Float16)fValue * (_Float16)fValue; + + fValue = (_Float16)*pInput++ - (_Float16)fMean; + fSum += (_Float16)fValue * (_Float16)fValue; + + fValue = (_Float16)*pInput++ - (_Float16)fMean; + fSum += (_Float16)fValue * (_Float16)fValue; + + /* 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) + { + fValue = (_Float16)*pInput++ - (_Float16)fMean; + fSum += (_Float16)fValue * (_Float16)fValue; + + /* Decrement loop counter */ + blkCnt--; + } + + /* Variance */ + *pResult = (_Float16)fSum / ((_Float16)blockSize - 1.0f16); +} +#endif /* defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */ + +/** + @} end of variance group + */ + +#endif /* #if defined(ARM_FLOAT16_SUPPORTED) */ + |