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Diffstat (limited to 'src/third_party/wiredtiger/src/checksum/arm64/crc32-arm64.c')
| -rw-r--r-- | src/third_party/wiredtiger/src/checksum/arm64/crc32-arm64.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/src/third_party/wiredtiger/src/checksum/arm64/crc32-arm64.c b/src/third_party/wiredtiger/src/checksum/arm64/crc32-arm64.c new file mode 100644 index 00000000000..5d6c5f69c58 --- /dev/null +++ b/src/third_party/wiredtiger/src/checksum/arm64/crc32-arm64.c @@ -0,0 +1,101 @@ +/*- + * Public Domain 2014-2016 MongoDB, Inc. + * Public Domain 2008-2014 WiredTiger, Inc. + * + * This is free and unencumbered software released into the public domain. + * + * Anyone is free to copy, modify, publish, use, compile, sell, or + * distribute this software, either in source code form or as a compiled + * binary, for any purpose, commercial or non-commercial, and by any + * means. + * + * In jurisdictions that recognize copyright laws, the author or authors + * of this software dedicate any and all copyright interest in the + * software to the public domain. We make this dedication for the benefit + * of the public at large and to the detriment of our heirs and + * successors. We intend this dedication to be an overt act of + * relinquishment in perpetuity of all present and future rights to this + * software under copyright law. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#include "wt_internal.h" + +#if defined(HAVE_CRC32_HARDWARE) +#include <asm/hwcap.h> +#include <sys/auxv.h> + +#define CRC32CX(crc,value) \ + asm("crc32cx %w[c], %w[c], %x[v]" : [c]"+r"(*&crc) : [v]"r"(+value)) +#define CRC32CW(crc,value) \ + asm("crc32cw %w[c], %w[c], %w[v]" : [c]"+r"(*&crc) : [v]"r"(+value)) +#define CRC32CH(crc,value) \ + asm("crc32ch %w[c], %w[c], %w[v]" : [c]"+r"(*&crc) : [v]"r"(+value)) +#define CRC32CB(crc,value) \ + asm("crc32cb %w[c], %w[c], %w[v]" : [c]"+r"(*&crc) : [v]"r"(+value)) + +/* + * __wt_checksum_hw -- + * Return a checksum for a chunk of memory, computed in hardware + * using 8 byte steps. + */ +static uint32_t +__wt_checksum_hw(const void *chunk, size_t len) +{ + uint32_t crc; + size_t nqwords; + const uint8_t *p; + const uint64_t *p64; + + crc = 0xffffffff; + + /* Checksum one byte at a time to the first 4B boundary. */ + for (p = chunk; + ((uintptr_t)p & (sizeof(uint32_t) - 1)) != 0 && + len > 0; ++p, --len) { + CRC32CB(crc, *p); + } + + p64 = (const uint64_t *)p; + /* Checksum in 8B chunks. */ + for (nqwords = len / sizeof(uint64_t); nqwords; nqwords--) { + CRC32CX(crc, *p64); + p64++; + } + + /* Checksum trailing bytes one byte at a time. */ + p = (const uint8_t *)p64; + for (len &= 0x7; len > 0; ++p, len--) { + CRC32CB(crc, *p); + } + + return (~crc); +} +#endif /* HAVE_CRC32_HARDWARE */ + +/* + * __wt_checksum_init -- + * WiredTiger: detect CRC hardware and set the checksum function. + */ +void +__wt_checksum_init(void) +{ +#if defined(HAVE_CRC32_HARDWARE) + unsigned long caps = getauxval(AT_HWCAP); + + if (caps & HWCAP_CRC32) + __wt_process.checksum = __wt_checksum_hw; + else + __wt_process.checksum = __wt_checksum_sw; + +#else /* !HAVE_CRC32_HARDWARE */ + __wt_process.checksum = __wt_checksum_sw; +#endif /* HAVE_CRC32_HARDWARE */ +} |