2019-06-30 18:13:46 -07:00

116 lines
2.8 KiB
C

/* crc32_acle.c -- compute the CRC-32 of a data stream
* Copyright (C) 1995-2006, 2010, 2011, 2012 Mark Adler
* Copyright (C) 2016 Yang Zhang
* For conditions of distribution and use, see copyright notice in zlib.h
*
*/
#ifdef __ARM_FEATURE_CRC32
# include <arm_acle.h>
# ifdef ZLIB_COMPAT
# include <zconf.h>
# else
# include <zconf-ng.h>
# endif
# ifdef __linux__
# include <stddef.h>
# endif
uint32_t crc32_acle(uint32_t crc, const unsigned char *buf, uint64_t len) {
register uint32_t c;
register const uint16_t *buf2;
register const uint32_t *buf4;
c = ~crc;
if (len && ((ptrdiff_t)buf & 1)) {
c = __crc32b(c, *buf++);
len--;
}
if ((len > sizeof(uint16_t)) && ((ptrdiff_t)buf & sizeof(uint16_t))) {
buf2 = (const uint16_t *) buf;
c = __crc32h(c, *buf2++);
len -= sizeof(uint16_t);
buf4 = (const uint32_t *) buf2;
} else {
buf4 = (const uint32_t *) buf;
}
# if defined(__aarch64__)
if ((len > sizeof(uint32_t)) && ((ptrdiff_t)buf & sizeof(uint32_t))) {
c = __crc32w(c, *buf4++);
len -= sizeof(uint32_t);
}
const uint64_t *buf8 = (const uint64_t *) buf4;
# ifdef UNROLL_MORE
while (len >= 4 * sizeof(uint64_t)) {
c = __crc32d(c, *buf8++);
c = __crc32d(c, *buf8++);
c = __crc32d(c, *buf8++);
c = __crc32d(c, *buf8++);
len -= 4 * sizeof(uint64_t);
}
# endif
while (len >= sizeof(uint64_t)) {
c = __crc32d(c, *buf8++);
len -= sizeof(uint64_t);
}
if (len >= sizeof(uint32_t)) {
buf4 = (const uint32_t *) buf8;
c = __crc32w(c, *buf4++);
len -= sizeof(uint32_t);
buf2 = (const uint16_t *) buf4;
} else {
buf2 = (const uint16_t *) buf8;
}
if (len >= sizeof(uint16_t)) {
c = __crc32h(c, *buf2++);
len -= sizeof(uint16_t);
}
buf = (const unsigned char *) buf2;
# else /* __aarch64__ */
# ifdef UNROLL_MORE
while (len >= 8 * sizeof(uint32_t)) {
c = __crc32w(c, *buf4++);
c = __crc32w(c, *buf4++);
c = __crc32w(c, *buf4++);
c = __crc32w(c, *buf4++);
c = __crc32w(c, *buf4++);
c = __crc32w(c, *buf4++);
c = __crc32w(c, *buf4++);
c = __crc32w(c, *buf4++);
len -= 8 * sizeof(uint32_t);
}
# endif
while (len >= sizeof(uint32_t)) {
c = __crc32w(c, *buf4++);
len -= sizeof(uint32_t);
}
if (len >= sizeof(uint16_t)) {
buf2 = (const uint16_t *) buf4;
c = __crc32h(c, *buf2++);
len -= sizeof(uint16_t);
buf = (const unsigned char *) buf2;
} else {
buf = (const unsigned char *) buf4;
}
# endif /* __aarch64__ */
if (len) {
c = __crc32b(c, *buf);
}
c = ~c;
return c;
}
#endif /* __ARM_FEATURE_CRC32 */