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/**
* \file crc32.h
*/
#if defined(__i386__) /* { */
#define partial_crc32 __z_partial_crc32
#define partial_crc32_copy __z_partial_crc32_copy
struct __crc32_fool_gcc {
char x[32768];
};
#if 0
#define PREFETCH(p) __asm__ __volatile__("prefetch %0": : "m" (*(struct __crc32_fool_gcc *)(p)))
#else
#define PREFETCH(p) (*(long *)(struct __crc32_fool_gcc *)(p))
#endif
#if 0
#define PREFETCH(p) do ; while (0)
#endif
static inline void partial_crc32_prep(uLong *crcp)
/*@modifies *crcp @*/
{
*crcp ^= 0xffffffffL;
}
static inline void partial_crc32_finish(uLong *crcp)
/*@modifies *crcp @*/
{
*crcp ^= 0xffffffffL;
}
static inline uLong get_crc_from_partial(uLong *crcp)
/*@modifies *crcp @*/
{
return *crcp ^ 0xffffffffL;
}
/*@observer@*/ /*@unchecked@*/
extern const uLongf crc_table[256];
#define DO1(buf) crc = crc_table[((int)crc ^ (*buf++)) & 0xff] ^ (crc >> 8);
static __inline__ uLong __partial_crc32(uLong crc, const Bytef *buf, uInt len, int copy, Bytef *dst)
/*@modifies *dst @*/
{
uInt n = len / 4;
#if 1 /* { */
#define DOlong(p, d) do { \
int i; \
crc ^= *(p); \
if (copy) \
*(d) = *(p); \
crc = crc_table[crc & 0xff] ^ (crc >> 8); \
crc = crc_table[crc & 0xff] ^ (crc >> 8); \
crc = crc_table[crc & 0xff] ^ (crc >> 8); \
crc = crc_table[crc & 0xff] ^ (crc >> 8); \
} while(0)
#if 0 /* { */
#define UPDcrc(x) crc =
#define DOlong(p) \
__asm__ __volatile__( \
"xorl %1,%0;" \
: "=a" (crc) \
: "0" (crc) \
: "ebx" \
)
#endif /* } */
if (n) {
long *x = (long *)buf;
long *y;
int j = n / 8;
PREFETCH(x);
PREFETCH(x+8);
PREFETCH(x+16);
if (copy)
y = (long *)dst;
while (n >= 8) {
PREFETCH(x+24);
/* I hate gcc. If I turn on loop unrolling,
* everything else is slowed down. */
DOlong(x+0, y+0);
DOlong(x+1, y+1);
DOlong(x+2, y+2);
DOlong(x+3, y+3);
DOlong(x+4, y+4);
DOlong(x+5, y+5);
DOlong(x+6, y+6);
DOlong(x+7, y+7);
x += 8;
y += 8;
n -= 8;
}
while (n--) {
DOlong(x, y);
x++;
y++;
}
buf = (Bytef *)x;
if (copy)
dst = (Bytef *)y;
}
len &= 3;
while (len--) {
if (copy)
*dst++ = *buf;
DO1(buf);
}
#else /* } { */
if (n) {
do {
DO4(buf);
} while (--n);
}
len &= 3;
switch(len) {
case 3:
if (copy)
*dst++ = *buf;
DO1(buf);
case 2:
if (copy)
*dst++ = *buf;
DO1(buf);
case 1:
if (copy)
*dst++ = *buf;
DO1(buf);
}
#endif /* } */
return crc;
}
#undef DO1
#undef DOlong
#if 0
#define partial_crc32(crc,buf,len) __partial_crc32(crc, buf, len, 0, 0)
#define partial_crc32_copy(crc,buf,len,dst) __partial_crc32((crc), (buf), (len), 1, (dst))
#endif
extern uLong partial_crc32(uLong crc, const Bytef *buf, uInt len) __attribute__((regparm(3)));
extern uLong partial_crc32_copy(uLong crcp, const Bytef *buf, uInt len, Bytef *dst) __attribute__((regparm(3)));
#endif /* } */
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