lib/lzo: Update LZO compression to current upstream version

This commit updates the kernel LZO code to the current upsteam version
which features a significant speed improvement - benchmarking the Calgary
and Silesia test corpora typically shows a doubled performance in
both compression and decompression on modern i386/x86_64/powerpc machines.

Signed-off-by: Markus F.X.J. Oberhumer <markus@oberhumer.com>
This commit is contained in:
Markus F.X.J. Oberhumer 2012-08-13 17:25:44 +02:00
parent b6bec26cea
commit 8b975bd3f9
4 changed files with 405 additions and 353 deletions

View file

@ -1,194 +1,243 @@
/*
* LZO1X Compressor from MiniLZO
* LZO1X Compressor from LZO
*
* Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com>
* Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com>
*
* The full LZO package can be found at:
* http://www.oberhumer.com/opensource/lzo/
*
* Changed for kernel use by:
* Changed for Linux kernel use by:
* Nitin Gupta <nitingupta910@gmail.com>
* Richard Purdie <rpurdie@openedhand.com>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/lzo.h>
#include <asm/unaligned.h>
#include <linux/lzo.h>
#include "lzodefs.h"
static noinline size_t
_lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
unsigned char *out, size_t *out_len, void *wrkmem)
lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
unsigned char *out, size_t *out_len,
size_t ti, void *wrkmem)
{
const unsigned char *ip;
unsigned char *op;
const unsigned char * const in_end = in + in_len;
const unsigned char * const ip_end = in + in_len - M2_MAX_LEN - 5;
const unsigned char ** const dict = wrkmem;
const unsigned char *ip = in, *ii = ip;
const unsigned char *end, *m, *m_pos;
size_t m_off, m_len, dindex;
unsigned char *op = out;
const unsigned char * const ip_end = in + in_len - 20;
const unsigned char *ii;
lzo_dict_t * const dict = (lzo_dict_t *) wrkmem;
ip += 4;
op = out;
ip = in;
ii = ip;
ip += ti < 4 ? 4 - ti : 0;
for (;;) {
dindex = ((size_t)(0x21 * DX3(ip, 5, 5, 6)) >> 5) & D_MASK;
m_pos = dict[dindex];
if (m_pos < in)
goto literal;
if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET))
goto literal;
m_off = ip - m_pos;
if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
goto try_match;
dindex = (dindex & (D_MASK & 0x7ff)) ^ (D_HIGH | 0x1f);
m_pos = dict[dindex];
if (m_pos < in)
goto literal;
if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET))
goto literal;
m_off = ip - m_pos;
if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3])
goto try_match;
goto literal;
try_match:
if (get_unaligned((const unsigned short *)m_pos)
== get_unaligned((const unsigned short *)ip)) {
if (likely(m_pos[2] == ip[2]))
goto match;
}
const unsigned char *m_pos;
size_t t, m_len, m_off;
u32 dv;
literal:
dict[dindex] = ip;
++ip;
ip += 1 + ((ip - ii) >> 5);
next:
if (unlikely(ip >= ip_end))
break;
continue;
match:
dict[dindex] = ip;
if (ip != ii) {
size_t t = ip - ii;
dv = get_unaligned_le32(ip);
t = ((dv * 0x1824429d) >> (32 - D_BITS)) & D_MASK;
m_pos = in + dict[t];
dict[t] = (lzo_dict_t) (ip - in);
if (unlikely(dv != get_unaligned_le32(m_pos)))
goto literal;
ii -= ti;
ti = 0;
t = ip - ii;
if (t != 0) {
if (t <= 3) {
op[-2] |= t;
} else if (t <= 18) {
COPY4(op, ii);
op += t;
} else if (t <= 16) {
*op++ = (t - 3);
COPY8(op, ii);
COPY8(op + 8, ii + 8);
op += t;
} else {
size_t tt = t - 18;
*op++ = 0;
while (tt > 255) {
tt -= 255;
if (t <= 18) {
*op++ = (t - 3);
} else {
size_t tt = t - 18;
*op++ = 0;
}
*op++ = tt;
}
do {
*op++ = *ii++;
} while (--t > 0);
}
ip += 3;
if (m_pos[3] != *ip++ || m_pos[4] != *ip++
|| m_pos[5] != *ip++ || m_pos[6] != *ip++
|| m_pos[7] != *ip++ || m_pos[8] != *ip++) {
--ip;
m_len = ip - ii;
if (m_off <= M2_MAX_OFFSET) {
m_off -= 1;
*op++ = (((m_len - 1) << 5)
| ((m_off & 7) << 2));
*op++ = (m_off >> 3);
} else if (m_off <= M3_MAX_OFFSET) {
m_off -= 1;
*op++ = (M3_MARKER | (m_len - 2));
goto m3_m4_offset;
} else {
m_off -= 0x4000;
*op++ = (M4_MARKER | ((m_off & 0x4000) >> 11)
| (m_len - 2));
goto m3_m4_offset;
}
} else {
end = in_end;
m = m_pos + M2_MAX_LEN + 1;
while (ip < end && *m == *ip) {
m++;
ip++;
}
m_len = ip - ii;
if (m_off <= M3_MAX_OFFSET) {
m_off -= 1;
if (m_len <= 33) {
*op++ = (M3_MARKER | (m_len - 2));
} else {
m_len -= 33;
*op++ = M3_MARKER | 0;
goto m3_m4_len;
}
} else {
m_off -= 0x4000;
if (m_len <= M4_MAX_LEN) {
*op++ = (M4_MARKER
| ((m_off & 0x4000) >> 11)
| (m_len - 2));
} else {
m_len -= M4_MAX_LEN;
*op++ = (M4_MARKER
| ((m_off & 0x4000) >> 11));
m3_m4_len:
while (m_len > 255) {
m_len -= 255;
while (unlikely(tt > 255)) {
tt -= 255;
*op++ = 0;
}
*op++ = (m_len);
*op++ = tt;
}
do {
COPY8(op, ii);
COPY8(op + 8, ii + 8);
op += 16;
ii += 16;
t -= 16;
} while (t >= 16);
if (t > 0) do {
*op++ = *ii++;
} while (--t > 0);
}
m3_m4_offset:
*op++ = ((m_off & 63) << 2);
*op++ = (m_off >> 6);
}
ii = ip;
if (unlikely(ip >= ip_end))
break;
}
m_len = 4;
{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ64)
u64 v;
v = get_unaligned((const u64 *) (ip + m_len)) ^
get_unaligned((const u64 *) (m_pos + m_len));
if (unlikely(v == 0)) {
do {
m_len += 8;
v = get_unaligned((const u64 *) (ip + m_len)) ^
get_unaligned((const u64 *) (m_pos + m_len));
if (unlikely(ip + m_len >= ip_end))
goto m_len_done;
} while (v == 0);
}
# if defined(__LITTLE_ENDIAN)
m_len += (unsigned) __builtin_ctzll(v) / 8;
# elif defined(__BIG_ENDIAN)
m_len += (unsigned) __builtin_clzll(v) / 8;
# else
# error "missing endian definition"
# endif
#elif defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ32)
u32 v;
v = get_unaligned((const u32 *) (ip + m_len)) ^
get_unaligned((const u32 *) (m_pos + m_len));
if (unlikely(v == 0)) {
do {
m_len += 4;
v = get_unaligned((const u32 *) (ip + m_len)) ^
get_unaligned((const u32 *) (m_pos + m_len));
if (v != 0)
break;
m_len += 4;
v = get_unaligned((const u32 *) (ip + m_len)) ^
get_unaligned((const u32 *) (m_pos + m_len));
if (unlikely(ip + m_len >= ip_end))
goto m_len_done;
} while (v == 0);
}
# if defined(__LITTLE_ENDIAN)
m_len += (unsigned) __builtin_ctz(v) / 8;
# elif defined(__BIG_ENDIAN)
m_len += (unsigned) __builtin_clz(v) / 8;
# else
# error "missing endian definition"
# endif
#else
if (unlikely(ip[m_len] == m_pos[m_len])) {
do {
m_len += 1;
if (ip[m_len] != m_pos[m_len])
break;
m_len += 1;
if (ip[m_len] != m_pos[m_len])
break;
m_len += 1;
if (ip[m_len] != m_pos[m_len])
break;
m_len += 1;
if (ip[m_len] != m_pos[m_len])
break;
m_len += 1;
if (ip[m_len] != m_pos[m_len])
break;
m_len += 1;
if (ip[m_len] != m_pos[m_len])
break;
m_len += 1;
if (ip[m_len] != m_pos[m_len])
break;
m_len += 1;
if (unlikely(ip + m_len >= ip_end))
goto m_len_done;
} while (ip[m_len] == m_pos[m_len]);
}
#endif
}
m_len_done:
m_off = ip - m_pos;
ip += m_len;
ii = ip;
if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) {
m_off -= 1;
*op++ = (((m_len - 1) << 5) | ((m_off & 7) << 2));
*op++ = (m_off >> 3);
} else if (m_off <= M3_MAX_OFFSET) {
m_off -= 1;
if (m_len <= M3_MAX_LEN)
*op++ = (M3_MARKER | (m_len - 2));
else {
m_len -= M3_MAX_LEN;
*op++ = M3_MARKER | 0;
while (unlikely(m_len > 255)) {
m_len -= 255;
*op++ = 0;
}
*op++ = (m_len);
}
*op++ = (m_off << 2);
*op++ = (m_off >> 6);
} else {
m_off -= 0x4000;
if (m_len <= M4_MAX_LEN)
*op++ = (M4_MARKER | ((m_off >> 11) & 8)
| (m_len - 2));
else {
m_len -= M4_MAX_LEN;
*op++ = (M4_MARKER | ((m_off >> 11) & 8));
while (unlikely(m_len > 255)) {
m_len -= 255;
*op++ = 0;
}
*op++ = (m_len);
}
*op++ = (m_off << 2);
*op++ = (m_off >> 6);
}
goto next;
}
*out_len = op - out;
return in_end - ii;
return in_end - (ii - ti);
}
int lzo1x_1_compress(const unsigned char *in, size_t in_len, unsigned char *out,
size_t *out_len, void *wrkmem)
int lzo1x_1_compress(const unsigned char *in, size_t in_len,
unsigned char *out, size_t *out_len,
void *wrkmem)
{
const unsigned char *ii;
const unsigned char *ip = in;
unsigned char *op = out;
size_t t;
size_t l = in_len;
size_t t = 0;
if (unlikely(in_len <= M2_MAX_LEN + 5)) {
t = in_len;
} else {
t = _lzo1x_1_do_compress(in, in_len, op, out_len, wrkmem);
while (l > 20) {
size_t ll = l <= (M4_MAX_OFFSET + 1) ? l : (M4_MAX_OFFSET + 1);
uintptr_t ll_end = (uintptr_t) ip + ll;
if ((ll_end + ((t + ll) >> 5)) <= ll_end)
break;
BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS);
memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t));
t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem);
ip += ll;
op += *out_len;
l -= ll;
}
t += l;
if (t > 0) {
ii = in + in_len - t;
const unsigned char *ii = in + in_len - t;
if (op == out && t <= 238) {
*op++ = (17 + t);
@ -198,16 +247,21 @@ int lzo1x_1_compress(const unsigned char *in, size_t in_len, unsigned char *out,
*op++ = (t - 3);
} else {
size_t tt = t - 18;
*op++ = 0;
while (tt > 255) {
tt -= 255;
*op++ = 0;
}
*op++ = tt;
}
do {
if (t >= 16) do {
COPY8(op, ii);
COPY8(op + 8, ii + 8);
op += 16;
ii += 16;
t -= 16;
} while (t >= 16);
if (t > 0) do {
*op++ = *ii++;
} while (--t > 0);
}
@ -223,4 +277,3 @@ EXPORT_SYMBOL_GPL(lzo1x_1_compress);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZO1X-1 Compressor");