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/*
* Copyright (c) 2022, Alliance for Open Media. All rights reserved.
*
* This source code is subject to the terms of the BSD 2 Clause License and
* the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
* was not distributed with this source code in the LICENSE file, you can
* obtain it at www.aomedia.org/license/software. If the Alliance for Open
* Media Patent License 1.0 was not distributed with this source code in the
* PATENTS file, you can obtain it at www.aomedia.org/license/patent.
*/
#if defined(_MSC_VER) && !defined(__clang__)
#include <intrin.h>
#else
#include <arm_acle.h>
#endif
#include <stddef.h>
#include <stdint.h>
#include "config/aom_config.h"
#include "config/av1_rtcd.h"
#define CRC_LOOP(op, crc, type, buf, len) \
while ((len) >= sizeof(type)) { \
(crc) = op((crc), *(type *)(buf)); \
(len) -= sizeof(type); \
buf += sizeof(type); \
}
#define CRC_SINGLE(op, crc, type, buf, len) \
if ((len) >= sizeof(type)) { \
(crc) = op((crc), *(type *)(buf)); \
(len) -= sizeof(type); \
buf += sizeof(type); \
}
/* Return 32-bit CRC for the input buffer.
* Polynomial is 0x1EDC6F41.
*/
uint32_t av1_get_crc32c_value_arm_crc32(void *crc_calculator, uint8_t *p,
size_t len) {
(void)crc_calculator;
const uint8_t *buf = p;
uint32_t crc = 0xFFFFFFFF;
#if !AOM_ARCH_AARCH64
// Align input to 8-byte boundary (only necessary for 32-bit builds.)
while (len && ((uintptr_t)buf & 7)) {
crc = __crc32cb(crc, *buf++);
len--;
}
#endif
CRC_LOOP(__crc32cd, crc, uint64_t, buf, len)
CRC_SINGLE(__crc32cw, crc, uint32_t, buf, len)
CRC_SINGLE(__crc32ch, crc, uint16_t, buf, len)
CRC_SINGLE(__crc32cb, crc, uint8_t, buf, len)
return ~crc;
}