| Index: xz/src/liblzma/check/crc64_fast.c
|
| ===================================================================
|
| --- xz/src/liblzma/check/crc64_fast.c (revision 0)
|
| +++ xz/src/liblzma/check/crc64_fast.c (revision 0)
|
| @@ -0,0 +1,72 @@
|
| +///////////////////////////////////////////////////////////////////////////////
|
| +//
|
| +/// \file crc64.c
|
| +/// \brief CRC64 calculation
|
| +///
|
| +/// Calculate the CRC64 using the slice-by-four algorithm. This is the same
|
| +/// idea that is used in crc32_fast.c, but for CRC64 we use only four tables
|
| +/// instead of eight to avoid increasing CPU cache usage.
|
| +//
|
| +// Author: Lasse Collin
|
| +//
|
| +// This file has been put into the public domain.
|
| +// You can do whatever you want with this file.
|
| +//
|
| +///////////////////////////////////////////////////////////////////////////////
|
| +
|
| +#include "check.h"
|
| +#include "crc_macros.h"
|
| +
|
| +
|
| +#ifdef WORDS_BIGENDIAN
|
| +# define A1(x) ((x) >> 56)
|
| +#else
|
| +# define A1 A
|
| +#endif
|
| +
|
| +
|
| +// See the comments in crc32_fast.c. They aren't duplicated here.
|
| +extern LZMA_API(uint64_t)
|
| +lzma_crc64(const uint8_t *buf, size_t size, uint64_t crc)
|
| +{
|
| + crc = ~crc;
|
| +
|
| +#ifdef WORDS_BIGENDIAN
|
| + crc = bswap64(crc);
|
| +#endif
|
| +
|
| + if (size > 4) {
|
| + while ((uintptr_t)(buf) & 3) {
|
| + crc = lzma_crc64_table[0][*buf++ ^ A1(crc)] ^ S8(crc);
|
| + --size;
|
| + }
|
| +
|
| + const uint8_t *const limit = buf + (size & ~(size_t)(3));
|
| + size &= (size_t)(3);
|
| +
|
| + while (buf < limit) {
|
| +#ifdef WORDS_BIGENDIAN
|
| + const uint32_t tmp = (crc >> 32)
|
| + ^ *(const uint32_t *)(buf);
|
| +#else
|
| + const uint32_t tmp = crc ^ *(const uint32_t *)(buf);
|
| +#endif
|
| + buf += 4;
|
| +
|
| + crc = lzma_crc64_table[3][A(tmp)]
|
| + ^ lzma_crc64_table[2][B(tmp)]
|
| + ^ S32(crc)
|
| + ^ lzma_crc64_table[1][C(tmp)]
|
| + ^ lzma_crc64_table[0][D(tmp)];
|
| + }
|
| + }
|
| +
|
| + while (size-- != 0)
|
| + crc = lzma_crc64_table[0][*buf++ ^ A1(crc)] ^ S8(crc);
|
| +
|
| +#ifdef WORDS_BIGENDIAN
|
| + crc = bswap64(crc);
|
| +#endif
|
| +
|
| + return ~crc;
|
| +}
|
|
|
| Property changes on: xz/src/liblzma/check/crc64_fast.c
|
| ___________________________________________________________________
|
| Added: svn:eol-style
|
| + LF
|
|
|
|
|