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>
diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c
index a604099..236eb21 100644
--- a/lib/lzo/lzo1x_compress.c
+++ b/lib/lzo/lzo1x_compress.c
@@ -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;
+ 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;
-match:
- dict[dindex] = ip;
- if (ip != ii) {
- size_t t = ip - ii;
-
+ 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 @@
*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 @@
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZO1X-1 Compressor");
-