Fork of mbed-dsp. CMSIS-DSP library of supporting NEON
Dependents: mbed-os-example-cmsis_dsp_neon
Fork of mbed-dsp by
Information
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このページの後半に日本語版が用意されています.
CMSIS-DSP of supporting NEON
What is this ?
A library for CMSIS-DSP of supporting NEON.
We supported the NEON to CMSIS-DSP Ver1.4.3(CMSIS V4.1) that ARM supplied, has achieved the processing speed improvement.
If you use the mbed-dsp library, you can use to replace this library.
CMSIS-DSP of supporting NEON is provied as a library.
Library Creation environment
CMSIS-DSP library of supporting NEON was created by the following environment.
- Compiler
ARMCC Version 5.03 - Compile option switch[C Compiler]
-DARM_MATH_MATRIX_CHECK -DARM_MATH_ROUNDING -O3 -Otime --cpu=Cortex-A9 --littleend --arm --apcs=/interwork --no_unaligned_access --fpu=vfpv3_fp16 --fpmode=fast --apcs=/hardfp --vectorize --asm
- Compile option switch[Assembler]
--cpreproc --cpu=Cortex-A9 --littleend --arm --apcs=/interwork --no_unaligned_access --fpu=vfpv3_fp16 --fpmode=fast --apcs=/hardfp
Effects of NEON support
In the data which passes to each function, large size will be expected more effective than small size.
Also if the data is a multiple of 16, effect will be expected in every function in the CMSIS-DSP.
NEON対応CMSIS-DSP
概要
NEON対応したCMSIS-DSPのライブラリです。
ARM社提供のCMSIS-DSP Ver1.4.3(CMSIS V4.1)をターゲットにNEON対応を行ない、処理速度向上を実現しております。
mbed-dspライブラリを使用している場合は、本ライブラリに置き換えて使用することができます。
NEON対応したCMSIS-DSPはライブラリで提供します。
ライブラリ作成環境
NEON対応CMSIS-DSPライブラリは、以下の環境で作成しています。
- コンパイラ
ARMCC Version 5.03 - コンパイルオプションスイッチ[C Compiler]
-DARM_MATH_MATRIX_CHECK -DARM_MATH_ROUNDING -O3 -Otime --cpu=Cortex-A9 --littleend --arm --apcs=/interwork --no_unaligned_access --fpu=vfpv3_fp16 --fpmode=fast --apcs=/hardfp --vectorize --asm
- コンパイルオプションスイッチ[Assembler]
--cpreproc --cpu=Cortex-A9 --littleend --arm --apcs=/interwork --no_unaligned_access --fpu=vfpv3_fp16 --fpmode=fast --apcs=/hardfp
NEON対応による効果について
CMSIS-DSP内の各関数へ渡すデータは、小さいサイズよりも大きいサイズの方が効果が見込めます。
また、16の倍数のデータであれば、CMSIS-DSP内のどの関数でも効果が見込めます。
Diff: cmsis_dsp/StatisticsFunctions/arm_max_q15.c
- Revision:
- 1:fdd22bb7aa52
- Child:
- 2:da51fb522205
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/StatisticsFunctions/arm_max_q15.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,168 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_max_q15.c +* +* Description: Maximum value of a Q15 vector. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* Version 1.0.10 2011/7/15 +* Big Endian support added and Merged M0 and M3/M4 Source code. +* +* Version 1.0.3 2010/11/29 +* Re-organized the CMSIS folders and updated documentation. +* +* Version 1.0.2 2010/11/11 +* Documentation updated. +* +* Version 1.0.1 2010/10/05 +* Production release and review comments incorporated. +* +* Version 1.0.0 2010/09/20 +* Production release and review comments incorporated. +* ---------------------------------------------------------------------------- */ + +#include "arm_math.h" + +/** + * @ingroup groupStats + */ + +/** + * @addtogroup Max + * @{ + */ + + +/** + * @brief Maximum value of a Q15 vector. + * @param[in] *pSrc points to the input vector + * @param[in] blockSize length of the input vector + * @param[out] *pResult maximum value returned here + * @param[out] *pIndex index of maximum value returned here + * @return none. + */ + +void arm_max_q15( + q15_t * pSrc, + uint32_t blockSize, + q15_t * pResult, + uint32_t * pIndex) +{ +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + q15_t maxVal1, maxVal2, out; /* Temporary variables to store the output value. */ + uint32_t blkCnt, outIndex, count; /* loop counter */ + + /* Initialise the count value. */ + count = 0u; + /* Initialise the index value to zero. */ + outIndex = 0u; + /* Load first input value that act as reference value for comparision */ + out = *pSrc++; + + /* Loop unrolling */ + blkCnt = (blockSize - 1u) >> 2u; + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + while(blkCnt > 0u) + { + /* Initialize maxVal to the next consecutive values one by one */ + maxVal1 = *pSrc++; + + maxVal2 = *pSrc++; + + /* compare for the maximum value */ + if(out < maxVal1) + { + /* Update the maximum value and its index */ + out = maxVal1; + outIndex = count + 1u; + } + + maxVal1 = *pSrc++; + + /* compare for the maximum value */ + if(out < maxVal2) + { + /* Update the maximum value and its index */ + out = maxVal2; + outIndex = count + 2u; + } + + maxVal2 = *pSrc++; + + /* compare for the maximum value */ + if(out < maxVal1) + { + /* Update the maximum value and its index */ + out = maxVal1; + outIndex = count + 3u; + } + + /* compare for the maximum value */ + if(out < maxVal2) + { + /* Update the maximum value and its index */ + out = maxVal2; + outIndex = count + 4u; + } + + count += 4u; + + /* Decrement the loop counter */ + blkCnt--; + } + + /* if (blockSize - 1u) is not multiple of 4 */ + blkCnt = (blockSize - 1u) % 4u; + +#else + + /* Run the below code for Cortex-M0 */ + q15_t maxVal1, out; /* Temporary variables to store the output value. */ + uint32_t blkCnt, outIndex; /* loop counter */ + + blkCnt = (blockSize - 1u); + + /* Initialise the index value to zero. */ + outIndex = 0u; + /* Load first input value that act as reference value for comparision */ + out = *pSrc++; + +#endif /* #ifndef ARM_MATH_CM0 */ + + while(blkCnt > 0u) + { + /* Initialize maxVal to the next consecutive values one by one */ + maxVal1 = *pSrc++; + + /* compare for the maximum value */ + if(out < maxVal1) + { + /* Update the maximum value and it's index */ + out = maxVal1; + outIndex = blockSize - blkCnt; + } + /* Decrement the loop counter */ + blkCnt--; + + } + + /* Store the maximum value and its index into destination pointers */ + *pResult = out; + *pIndex = outIndex; +} + +/** + * @} end of Max group + */