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Jinliang Li
d5db7d1cee
Optimize crc32 standard(poly:0x04C11DB7) and crc32 castagnoli(poly:0x1EDC6F41) with arm crc32 extension instructions. For example, crc32 standard caculates(lookup crc32 table) 1812 bytes data, reduced the time from 118 us to 14 us through optimization. Performance improved ~700% Signed-off-by: Jinliang Li <lijinliang1@lixiang.com>
116 lines
3.2 KiB
C
116 lines
3.2 KiB
C
/****************************************************************************
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* libs/libc/machine/arm/arch_crc32.c
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*
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* SPDX-License-Identifier: Apache-2.0
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <stdint.h>
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#include <sys/types.h>
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#include <arm_acle.h>
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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/****************************************************************************
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* Name: crc32part
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*
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* Description:
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* crc32 polynomial 0x04C11DB7 (bitreflected 0xEDB88320)
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*
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****************************************************************************/
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uint32_t crc32part(FAR const uint8_t *src, size_t len, uint32_t crc32val)
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{
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size_t i = 0;
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for (; (i + 8) <= len; i += 8)
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{
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uint64_t data = *(uint64_t *)(src + i);
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crc32val = __crc32d(crc32val, data);
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}
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if (i + 4 <= len)
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{
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uint32_t data = *(uint32_t *)(src + i);
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crc32val = __crc32w(crc32val, data);
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i += 4;
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}
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if (i + 2 <= len)
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{
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uint16_t data = *(uint16_t *)(src + i);
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crc32val = __crc32h(crc32val, data);
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i += 2;
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}
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if (i < len)
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{
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uint8_t data = *(uint8_t *)(src + i);
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crc32val = __crc32b(crc32val, data);
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}
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return crc32val;
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}
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/****************************************************************************
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* Name: crc32part_c
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*
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* Description:
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* crc32 Castagnoli polynomial 0x1EDC6F41
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*
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****************************************************************************/
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uint32_t crc32part_c(FAR const uint8_t *src, size_t len, uint32_t crc32val)
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{
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size_t i = 0;
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for (; (i + 8) <= len; i += 8)
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{
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uint64_t data = *(uint64_t *)(src + i);
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crc32val = __crc32cd(crc32val, data);
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}
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if (i + 4 <= len)
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{
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uint32_t data = *(uint32_t *)(src + i);
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crc32val = __crc32cw(crc32val, data);
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i += 4;
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}
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if (i + 2 <= len)
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{
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uint16_t data = *(uint16_t *)(src + i);
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crc32val = __crc32ch(crc32val, data);
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i += 2;
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}
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if (i < len)
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{
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uint8_t data = *(uint8_t *)(src + i);
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crc32val = __crc32cb(crc32val, data);
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}
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return crc32val;
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}
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