mariadb/mysys/crc32ieee.cc
Vladislav Vaintroub ccbe6bb6fc MDEV-19935 Create unified CRC-32 interface
Add CRC32C code to mysys. The x86-64 implementation uses PCMULQDQ in addition to CRC32 instruction
after Intel whitepaper, and is ported from rocksdb code.

Optimized ARM and POWER CRC32 were already present in mysys.
2020-09-17 16:07:37 +02:00

63 lines
2 KiB
C++

/* Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1335 USA */
#include <my_global.h>
#include <my_sys.h>
#include <zlib.h>
/* TODO: remove this once zlib adds inherent support for hardware accelerated
crc32 for all architectures. */
static unsigned int my_crc32_zlib(unsigned int crc, const void *data,
size_t len)
{
return (unsigned int) crc32(crc, (const Bytef *)data, (unsigned int) len);
}
#ifdef HAVE_PCLMUL
extern "C" int crc32_pclmul_enabled();
extern "C" unsigned int crc32_pclmul(unsigned int, const void *, size_t);
#elif defined(__GNUC__) && defined(HAVE_ARMV8_CRC)
extern "C" int crc32_aarch64_available();
extern "C" unsigned int crc32_aarch64(unsigned int, const void *, size_t);
#endif
typedef unsigned int (*my_crc32_t)(unsigned int, const void *, size_t);
static my_crc32_t init_crc32()
{
my_crc32_t func= my_crc32_zlib;
#ifdef HAVE_PCLMUL
if (crc32_pclmul_enabled())
func = crc32_pclmul;
#elif defined(__GNUC__) && defined(HAVE_ARMV8_CRC)
if (crc32_aarch64_available())
func= crc32_aarch64;
#endif
return func;
}
static const my_crc32_t my_checksum_func= init_crc32();
#ifndef __powerpc64__
/* For powerpc, my_checksum is defined elsewhere.*/
extern "C" unsigned int my_checksum(unsigned int crc, const void *data, size_t len)
{
return my_checksum_func(crc, data, len);
}
#endif