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/*-
* BSD LICENSE
*
* Copyright (c) Intel Corporation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "spdk/crc32.h"
#if defined(__x86_64__) && defined(__SSE4_2__)
#include <x86intrin.h>
uint32_t
spdk_crc32c_update(const void *buf, size_t len, uint32_t crc)
{
uint64_t crc_tmp64;
size_t count;
/* _mm_crc32_u64() needs a 64-bit intermediate value */
crc_tmp64 = crc;
/* Process as much of the buffer as possible in 64-bit blocks. */
count = len / 8;
while (count--) {
uint64_t block;
/*
* Use memcpy() to avoid unaligned loads, which are undefined behavior in C.
* The compiler will optimize out the memcpy() in release builds.
*/
memcpy(&block, buf, sizeof(block));
crc_tmp64 = _mm_crc32_u64(crc_tmp64, block);
buf += sizeof(block);
}
crc = (uint32_t)crc_tmp64;
/* Handle any trailing bytes. */
count = len & 7;
while (count--) {
crc = _mm_crc32_u8(crc, *(const uint8_t *)buf);
buf++;
}
return crc;
}
#else /* SSE 4.2 (CRC32 instruction) not available */
static struct spdk_crc32_table g_crc32c_table;
__attribute__((constructor)) static void
spdk_crc32c_init(void)
{
spdk_crc32_table_init(&g_crc32c_table, SPDK_CRC32C_POLYNOMIAL_REFLECT);
}
uint32_t
spdk_crc32c_update(const void *buf, size_t len, uint32_t crc)
{
return spdk_crc32_update(&g_crc32c_table, buf, len, crc);
}
#endif
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