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authorAkinobu Mita <akinobu.mita@gmail.com>2006-12-08 02:36:25 -0800
committerLinus Torvalds <torvalds@woody.osdl.org>2006-12-08 08:28:39 -0800
commit906d66df18faa4aac8d898ae6920d1014694a932 (patch)
treedf91905b3c79b7af39091e82655088ad5057379e /lib/crc32.c
parenta5cfc1ec58a07074dacb6aa8c79eff864c966d12 (diff)
[PATCH] crc32: replace bitreverse by bitrev32
This patch replaces bitreverse() by bitrev32. The only users of bitreverse() are crc32 itself and via-velocity. Cc: Jeff Garzik <jgarzik@pobox.com> Cc: Matt Domsch <Matt_Domsch@dell.com> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'lib/crc32.c')
-rw-r--r--lib/crc32.c28
1 files changed, 5 insertions, 23 deletions
diff --git a/lib/crc32.c b/lib/crc32.c
index 285fd9bc61be..bfc33314c720 100644
--- a/lib/crc32.c
+++ b/lib/crc32.c
@@ -235,23 +235,8 @@ u32 __attribute_pure__ crc32_be(u32 crc, unsigned char const *p, size_t len)
}
#endif
-/**
- * bitreverse - reverse the order of bits in a u32 value
- * @x: value to be bit-reversed
- */
-u32 bitreverse(u32 x)
-{
- x = (x >> 16) | (x << 16);
- x = (x >> 8 & 0x00ff00ff) | (x << 8 & 0xff00ff00);
- x = (x >> 4 & 0x0f0f0f0f) | (x << 4 & 0xf0f0f0f0);
- x = (x >> 2 & 0x33333333) | (x << 2 & 0xcccccccc);
- x = (x >> 1 & 0x55555555) | (x << 1 & 0xaaaaaaaa);
- return x;
-}
-
EXPORT_SYMBOL(crc32_le);
EXPORT_SYMBOL(crc32_be);
-EXPORT_SYMBOL(bitreverse);
/*
* A brief CRC tutorial.
@@ -400,10 +385,7 @@ buf_dump(char const *prefix, unsigned char const *buf, size_t len)
static void bytereverse(unsigned char *buf, size_t len)
{
while (len--) {
- unsigned char x = *buf;
- x = (x >> 4) | (x << 4);
- x = (x >> 2 & 0x33) | (x << 2 & 0xcc);
- x = (x >> 1 & 0x55) | (x << 1 & 0xaa);
+ unsigned char x = bitrev8(*buf);
*buf++ = x;
}
}
@@ -460,11 +442,11 @@ static u32 test_step(u32 init, unsigned char *buf, size_t len)
/* Now swap it around for the other test */
bytereverse(buf, len + 4);
- init = bitreverse(init);
- crc2 = bitreverse(crc1);
- if (crc1 != bitreverse(crc2))
+ init = bitrev32(init);
+ crc2 = bitrev32(crc1);
+ if (crc1 != bitrev32(crc2))
printf("\nBit reversal fail: 0x%08x -> 0x%08x -> 0x%08x\n",
- crc1, crc2, bitreverse(crc2));
+ crc1, crc2, bitrev32(crc2));
crc1 = crc32_le(init, buf, len);
if (crc1 != crc2)
printf("\nCRC endianness fail: 0x%08x != 0x%08x\n", crc1,

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