@@ -53,20 +53,21 @@ static inline u32
crc32_body(u32 crc, unsigned char const *buf, size_t len, const u32 (*tab)[256])
{
# ifdef __LITTLE_ENDIAN
-# define DO_CRC(x) crc = tab[0][(crc ^ (x)) & 255] ^ (crc >> 8)
-# define DO_CRC4 crc = tab[3][(crc) & 255] ^ \
- tab[2][(crc >> 8) & 255] ^ \
- tab[1][(crc >> 16) & 255] ^ \
- tab[0][(crc >> 24) & 255]
+# define DO_CRC(x) (crc = t0[(crc ^ (x)) & 255] ^ (crc >> 8))
+# define DO_CRC4 crc = t3[(crc) & 255] ^ \
+ t2[(crc >> 8) & 255] ^ \
+ t1[(crc >> 16) & 255] ^ \
+ t0[(crc >> 24) & 255]
# else
-# define DO_CRC(x) crc = tab[0][((crc >> 24) ^ (x)) & 255] ^ (crc << 8)
-# define DO_CRC4 crc = tab[0][(crc) & 255] ^ \
- tab[1][(crc >> 8) & 255] ^ \
- tab[2][(crc >> 16) & 255] ^ \
- tab[3][(crc >> 24) & 255]
+# define DO_CRC(x) (crc = t0[((crc >> 24) ^ (x)) & 255] ^ (crc << 8))
+# define DO_CRC4 crc = t0[(crc) & 255] ^ \
+ t1[(crc >> 8) & 255] ^ \
+ t2[(crc >> 16) & 255] ^ \
+ t3[(crc >> 24) & 255]
# endif
const u32 *b;
size_t rem_len;
+ const u32 *t0 = tab[0], *t1 = tab[1], *t2 = tab[2], *t3 = tab[3];
/* Align it */
if (unlikely((long)buf & 3 && len)) {
This change has no effect on X86 code but improves PPC performance. Signed-off-by: Bob Pearson <rpearson@systemfabricworks.com> --- lib/crc32.c | 21 +++++++++++---------- 1 files changed, 11 insertions(+), 10 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html