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#if defined(__powerpc64__)
#define CRC_TABLE
#include "crc32_constants.h"
#define VMX_ALIGN 16U
#define VMX_ALIGN_MASK (VMX_ALIGN-1)
#ifdef REFLECT
static unsigned int crc32_align(unsigned int crc, const unsigned char *p,
unsigned long len)
{
while (len--)
crc = crc_table[(crc ^ *p++) & 0xff] ^ (crc >> 8);
return crc;
}
#else
static unsigned int crc32_align(unsigned int crc, const unsigned char *p,
unsigned long len)
{
while (len--)
crc = crc_table[((crc >> 24) ^ *p++) & 0xff] ^ (crc << 8);
return crc;
}
#endif
unsigned int __crc32_vpmsum(unsigned int crc, const unsigned char *p,
unsigned long len);
/* -Werror=missing-prototypes */
unsigned int crc32_vpmsum(unsigned int crc, const unsigned char *p,
unsigned long len);
unsigned int crc32_vpmsum(unsigned int crc, const unsigned char *p,
unsigned long len)
{
unsigned int prealign;
unsigned int tail;
#ifdef CRC_XOR
crc ^= 0xffffffff;
#endif
if (len < VMX_ALIGN + VMX_ALIGN_MASK) {
crc = crc32_align(crc, p, len);
goto out;
}
if ((unsigned long)p & VMX_ALIGN_MASK) {
prealign = VMX_ALIGN - ((unsigned long)p & VMX_ALIGN_MASK);
crc = crc32_align(crc, p, prealign);
len -= prealign;
p += prealign;
}
crc = __crc32_vpmsum(crc, p, len & ~VMX_ALIGN_MASK);
tail = len & VMX_ALIGN_MASK;
if (tail) {
p += len & ~VMX_ALIGN_MASK;
crc = crc32_align(crc, p, tail);
}
out:
#ifdef CRC_XOR
crc ^= 0xffffffff;
#endif
return crc;
}
#endif
#include "wt_internal.h"
/*
* __wt_checksum_hw --
* WiredTiger: return a checksum for a chunk of memory.
*/
static uint32_t
__wt_checksum_hw(const void *chunk, size_t len)
{
return (crc32_vpmsum(0, chunk, len));
}
/*
* __wt_checksum_init --
* WiredTiger: detect CRC hardware and set the checksum function.
*/
void
__wt_checksum_init(void)
{
#if defined(HAVE_CRC32_HARDWARE)
__wt_process.checksum = __wt_checksum_hw;
#else
__wt_process.checksum = __wt_checksum_sw;
#endif
}
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