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authorDenys Vlasenko2009-09-15 23:40:08 +0200
committerDenys Vlasenko2009-09-15 23:40:08 +0200
commitf2c184be835fbcbd04d06fce22783c6a5d37b563 (patch)
tree62f0f5ca34a5768e0472cd4a7527801018e2af25 /archival/libunarchive/decompress_unlzma.c
parentba98603264125aceac59c36a36dfbee0f7f67c7f (diff)
downloadbusybox-f2c184be835fbcbd04d06fce22783c6a5d37b563.zip
busybox-f2c184be835fbcbd04d06fce22783c6a5d37b563.tar.gz
unlzma: fixed speedup/shrink by Pascal Bellard (pascal.bellard AT ads-lu.com)
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Diffstat (limited to 'archival/libunarchive/decompress_unlzma.c')
-rw-r--r--archival/libunarchive/decompress_unlzma.c250
1 files changed, 106 insertions, 144 deletions
diff --git a/archival/libunarchive/decompress_unlzma.c b/archival/libunarchive/decompress_unlzma.c
index 33e5cd6..4478cd2 100644
--- a/archival/libunarchive/decompress_unlzma.c
+++ b/archival/libunarchive/decompress_unlzma.c
@@ -8,14 +8,15 @@
*
* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*/
-
#include "libbb.h"
#include "unarchive.h"
#if ENABLE_FEATURE_LZMA_FAST
# define speed_inline ALWAYS_INLINE
+# define size_inline
#else
# define speed_inline
+# define size_inline ALWAYS_INLINE
#endif
@@ -44,36 +45,48 @@ typedef struct {
#define RC_MODEL_TOTAL_BITS 11
-/* Called twice: once at startup and once in rc_normalize() */
-static void rc_read(rc_t *rc)
+/* Called twice: once at startup (LZMA_FAST only) and once in rc_normalize() */
+static size_inline void rc_read(rc_t *rc)
{
int buffer_size = safe_read(rc->fd, RC_BUFFER, RC_BUFFER_SIZE);
+//TODO: return -1 instead
+//This will make unlzma delete broken unpacked file on unpack errors
if (buffer_size <= 0)
bb_error_msg_and_die("unexpected EOF");
rc->ptr = RC_BUFFER;
rc->buffer_end = RC_BUFFER + buffer_size;
}
+/* Called twice, but one callsite is in speed_inline'd rc_is_bit_1() */
+static void rc_do_normalize(rc_t *rc)
+{
+ if (rc->ptr >= rc->buffer_end)
+ rc_read(rc);
+ rc->range <<= 8;
+ rc->code = (rc->code << 8) | *rc->ptr++;
+}
+
/* Called once */
-static rc_t* rc_init(int fd) /*, int buffer_size) */
+static ALWAYS_INLINE rc_t* rc_init(int fd) /*, int buffer_size) */
{
int i;
rc_t *rc;
- rc = xmalloc(sizeof(*rc) + RC_BUFFER_SIZE);
+ rc = xzalloc(sizeof(*rc) + RC_BUFFER_SIZE);
rc->fd = fd;
- /* rc->buffer_size = buffer_size; */
- rc->buffer_end = RC_BUFFER + RC_BUFFER_SIZE;
- rc->ptr = rc->buffer_end;
+ /* rc->ptr = rc->buffer_end; */
- rc->code = 0;
- rc->range = 0xFFFFFFFF;
for (i = 0; i < 5; i++) {
+#if ENABLE_FEATURE_LZMA_FAST
if (rc->ptr >= rc->buffer_end)
rc_read(rc);
rc->code = (rc->code << 8) | *rc->ptr++;
+#else
+ rc_do_normalize(rc);
+#endif
}
+ rc->range = 0xFFFFFFFF;
return rc;
}
@@ -83,14 +96,6 @@ static ALWAYS_INLINE void rc_free(rc_t *rc)
free(rc);
}
-/* Called twice, but one callsite is in speed_inline'd rc_is_bit_0_helper() */
-static void rc_do_normalize(rc_t *rc)
-{
- if (rc->ptr >= rc->buffer_end)
- rc_read(rc);
- rc->range <<= 8;
- rc->code = (rc->code << 8) | *rc->ptr++;
-}
static ALWAYS_INLINE void rc_normalize(rc_t *rc)
{
if (rc->range < (1 << RC_TOP_BITS)) {
@@ -98,49 +103,28 @@ static ALWAYS_INLINE void rc_normalize(rc_t *rc)
}
}
-/* rc_is_bit_0 is called 9 times */
-/* Why rc_is_bit_0_helper exists?
- * Because we want to always expose (rc->code < rc->bound) to optimizer.
- * Thus rc_is_bit_0 is always inlined, and rc_is_bit_0_helper is inlined
- * only if we compile for speed.
- */
-static speed_inline uint32_t rc_is_bit_0_helper(rc_t *rc, uint16_t *p)
+/* rc_is_bit_1 is called 9 times */
+static speed_inline int rc_is_bit_1(rc_t *rc, uint16_t *p)
{
rc_normalize(rc);
rc->bound = *p * (rc->range >> RC_MODEL_TOTAL_BITS);
- return rc->bound;
-}
-static ALWAYS_INLINE int rc_is_bit_0(rc_t *rc, uint16_t *p)
-{
- uint32_t t = rc_is_bit_0_helper(rc, p);
- return rc->code < t;
-}
-
-/* Called ~10 times, but very small, thus inlined */
-static speed_inline void rc_update_bit_0(rc_t *rc, uint16_t *p)
-{
- rc->range = rc->bound;
- *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
-}
-static speed_inline void rc_update_bit_1(rc_t *rc, uint16_t *p)
-{
+ if (rc->code < rc->bound) {
+ rc->range = rc->bound;
+ *p += ((1 << RC_MODEL_TOTAL_BITS) - *p) >> RC_MOVE_BITS;
+ return 0;
+ }
rc->range -= rc->bound;
rc->code -= rc->bound;
*p -= *p >> RC_MOVE_BITS;
+ return 1;
}
/* Called 4 times in unlzma loop */
-static int rc_get_bit(rc_t *rc, uint16_t *p, int *symbol)
+static speed_inline int rc_get_bit(rc_t *rc, uint16_t *p, int *symbol)
{
- if (rc_is_bit_0(rc, p)) {
- rc_update_bit_0(rc, p);
- *symbol *= 2;
- return 0;
- } else {
- rc_update_bit_1(rc, p);
- *symbol = *symbol * 2 + 1;
- return 1;
- }
+ int ret = rc_is_bit_1(rc, p);
+ *symbol = *symbol * 2 + ret;
+ return ret;
}
/* Called once */
@@ -236,14 +220,11 @@ unpack_lzma_stream(int src_fd, int dst_fd)
int lc, pb, lp;
uint32_t pos_state_mask;
uint32_t literal_pos_mask;
- uint32_t pos;
uint16_t *p;
- uint16_t *prob;
- uint16_t *prob_lit;
int num_bits;
int num_probs;
rc_t *rc;
- int i, mi;
+ int i;
uint8_t *buffer;
uint8_t previous_byte = 0;
size_t buffer_pos = 0, global_pos = 0;
@@ -251,14 +232,17 @@ unpack_lzma_stream(int src_fd, int dst_fd)
int state = 0;
uint32_t rep0 = 1, rep1 = 1, rep2 = 1, rep3 = 1;
- xread(src_fd, &header, sizeof(header));
+ if (full_read(src_fd, &header, sizeof(header)) != sizeof(header)
+ || header.pos >= (9 * 5 * 5)
+ ) {
+ bb_error_msg("bad lzma header");
+ return -1;
+ }
- if (header.pos >= (9 * 5 * 5))
- bb_error_msg_and_die("bad header");
- mi = header.pos / 9;
+ i = header.pos / 9;
lc = header.pos % 9;
- pb = mi / 5;
- lp = mi % 5;
+ pb = i / 5;
+ lp = i % 5;
pos_state_mask = (1 << pb) - 1;
literal_pos_mask = (1 << lp) - 1;
@@ -266,13 +250,13 @@ unpack_lzma_stream(int src_fd, int dst_fd)
header.dst_size = SWAP_LE64(header.dst_size);
if (header.dict_size == 0)
- header.dict_size = 1;
+ header.dict_size++;
buffer = xmalloc(MIN(header.dst_size, header.dict_size));
num_probs = LZMA_BASE_SIZE + (LZMA_LIT_SIZE << (lc + lp));
p = xmalloc(num_probs * sizeof(*p));
- num_probs = LZMA_LITERAL + (LZMA_LIT_SIZE << (lc + lp));
+ num_probs += LZMA_LITERAL - LZMA_BASE_SIZE;
for (i = 0; i < num_probs; i++)
p[i] = (1 << RC_MODEL_TOTAL_BITS) >> 1;
@@ -280,11 +264,13 @@ unpack_lzma_stream(int src_fd, int dst_fd)
while (global_pos + buffer_pos < header.dst_size) {
int pos_state = (buffer_pos + global_pos) & pos_state_mask;
+ uint16_t *prob = p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
+
+ if (!rc_is_bit_1(rc, prob)) {
+ static const char next_state[LZMA_NUM_STATES] =
+ { 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 4, 5 };
+ int mi = 1;
- prob = p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state;
- if (rc_is_bit_0(rc, prob)) {
- mi = 1;
- rc_update_bit_0(rc, prob);
prob = (p + LZMA_LITERAL
+ (LZMA_LIT_SIZE * ((((buffer_pos + global_pos) & literal_pos_mask) << lc)
+ (previous_byte >> (8 - lc))
@@ -294,8 +280,8 @@ unpack_lzma_stream(int src_fd, int dst_fd)
if (state >= LZMA_NUM_LIT_STATES) {
int match_byte;
+ uint32_t pos = buffer_pos - rep0;
- pos = buffer_pos - rep0;
while (pos >= header.dict_size)
pos += header.dict_size;
match_byte = buffer[pos];
@@ -304,22 +290,16 @@ unpack_lzma_stream(int src_fd, int dst_fd)
match_byte <<= 1;
bit = match_byte & 0x100;
- prob_lit = prob + 0x100 + bit + mi;
- bit ^= (rc_get_bit(rc, prob_lit, &mi) << 8); /* 0x100 or 0 */
+ bit ^= (rc_get_bit(rc, prob + 0x100 + bit + mi, &mi) << 8); /* 0x100 or 0 */
if (bit)
break;
} while (mi < 0x100);
}
while (mi < 0x100) {
- prob_lit = prob + mi;
- rc_get_bit(rc, prob_lit, &mi);
+ rc_get_bit(rc, prob + mi, &mi);
}
- state -= 3;
- if (state < 4-3)
- state = 0;
- if (state >= 10-3)
- state -= 6-3;
+ state = next_state[state];
previous_byte = (uint8_t) mi;
#if ENABLE_FEATURE_LZMA_FAST
@@ -338,59 +318,46 @@ unpack_lzma_stream(int src_fd, int dst_fd)
#endif
} else {
int offset;
- uint16_t *prob_len;
+ uint16_t *prob2;
+#define prob_len prob2
- rc_update_bit_1(rc, prob);
- prob = p + LZMA_IS_REP + state;
- if (rc_is_bit_0(rc, prob)) {
- rc_update_bit_0(rc, prob);
+ prob2 = p + LZMA_IS_REP + state;
+ if (!rc_is_bit_1(rc, prob2)) {
rep3 = rep2;
rep2 = rep1;
rep1 = rep0;
state = state < LZMA_NUM_LIT_STATES ? 0 : 3;
- prob = p + LZMA_LEN_CODER;
+ prob2 = p + LZMA_LEN_CODER;
} else {
- rc_update_bit_1(rc, prob);
- prob = p + LZMA_IS_REP_G0 + state;
- if (rc_is_bit_0(rc, prob)) {
- rc_update_bit_0(rc, prob);
- prob = (p + LZMA_IS_REP_0_LONG
+ prob2 += LZMA_IS_REP_G0 - LZMA_IS_REP;
+ if (!rc_is_bit_1(rc, prob2)) {
+ prob2 = (p + LZMA_IS_REP_0_LONG
+ (state << LZMA_NUM_POS_BITS_MAX)
+ pos_state
);
- if (rc_is_bit_0(rc, prob)) {
- rc_update_bit_0(rc, prob);
-
- state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
+ if (!rc_is_bit_1(rc, prob2)) {
#if ENABLE_FEATURE_LZMA_FAST
- pos = buffer_pos - rep0;
+ uint32_t pos = buffer_pos - rep0;
+ state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
while (pos >= header.dict_size)
pos += header.dict_size;
previous_byte = buffer[pos];
goto one_byte1;
#else
+ state = state < LZMA_NUM_LIT_STATES ? 9 : 11;
len = 1;
goto string;
#endif
- } else {
- rc_update_bit_1(rc, prob);
}
} else {
uint32_t distance;
- rc_update_bit_1(rc, prob);
- prob = p + LZMA_IS_REP_G1 + state;
- if (rc_is_bit_0(rc, prob)) {
- rc_update_bit_0(rc, prob);
- distance = rep1;
- } else {
- rc_update_bit_1(rc, prob);
- prob = p + LZMA_IS_REP_G2 + state;
- if (rc_is_bit_0(rc, prob)) {
- rc_update_bit_0(rc, prob);
- distance = rep2;
- } else {
- rc_update_bit_1(rc, prob);
+ prob2 += LZMA_IS_REP_G1 - LZMA_IS_REP_G0;
+ distance = rep1;
+ if (rc_is_bit_1(rc, prob2)) {
+ prob2 += LZMA_IS_REP_G2 - LZMA_IS_REP_G1;
+ distance = rep2;
+ if (rc_is_bit_1(rc, prob2)) {
distance = rep3;
rep3 = rep2;
}
@@ -400,31 +367,27 @@ unpack_lzma_stream(int src_fd, int dst_fd)
rep0 = distance;
}
state = state < LZMA_NUM_LIT_STATES ? 8 : 11;
- prob = p + LZMA_REP_LEN_CODER;
+ prob2 = p + LZMA_REP_LEN_CODER;
}
- prob_len = prob + LZMA_LEN_CHOICE;
- if (rc_is_bit_0(rc, prob_len)) {
- rc_update_bit_0(rc, prob_len);
- prob_len = (prob + LZMA_LEN_LOW
- + (pos_state << LZMA_LEN_NUM_LOW_BITS));
+ prob_len = prob2 + LZMA_LEN_CHOICE;
+ num_bits = LZMA_LEN_NUM_LOW_BITS;
+ if (!rc_is_bit_1(rc, prob_len)) {
+ prob_len += LZMA_LEN_LOW - LZMA_LEN_CHOICE
+ + (pos_state << LZMA_LEN_NUM_LOW_BITS);
offset = 0;
- num_bits = LZMA_LEN_NUM_LOW_BITS;
} else {
- rc_update_bit_1(rc, prob_len);
- prob_len = prob + LZMA_LEN_CHOICE_2;
- if (rc_is_bit_0(rc, prob_len)) {
- rc_update_bit_0(rc, prob_len);
- prob_len = (prob + LZMA_LEN_MID
- + (pos_state << LZMA_LEN_NUM_MID_BITS));
+ prob_len += LZMA_LEN_CHOICE_2 - LZMA_LEN_CHOICE;
+ if (!rc_is_bit_1(rc, prob_len)) {
+ prob_len += LZMA_LEN_MID - LZMA_LEN_CHOICE_2
+ + (pos_state << LZMA_LEN_NUM_MID_BITS);
offset = 1 << LZMA_LEN_NUM_LOW_BITS;
- num_bits = LZMA_LEN_NUM_MID_BITS;
+ num_bits += LZMA_LEN_NUM_MID_BITS - LZMA_LEN_NUM_LOW_BITS;
} else {
- rc_update_bit_1(rc, prob_len);
- prob_len = prob + LZMA_LEN_HIGH;
+ prob_len += LZMA_LEN_HIGH - LZMA_LEN_CHOICE_2;
offset = ((1 << LZMA_LEN_NUM_LOW_BITS)
+ (1 << LZMA_LEN_NUM_MID_BITS));
- num_bits = LZMA_LEN_NUM_HIGH_BITS;
+ num_bits += LZMA_LEN_NUM_HIGH_BITS - LZMA_LEN_NUM_LOW_BITS;
}
}
rc_bit_tree_decode(rc, prob_len, num_bits, &len);
@@ -432,37 +395,36 @@ unpack_lzma_stream(int src_fd, int dst_fd)
if (state < 4) {
int pos_slot;
+ uint16_t *prob3;
state += LZMA_NUM_LIT_STATES;
- prob = p + LZMA_POS_SLOT +
+ prob3 = p + LZMA_POS_SLOT +
((len < LZMA_NUM_LEN_TO_POS_STATES ? len :
LZMA_NUM_LEN_TO_POS_STATES - 1)
<< LZMA_NUM_POS_SLOT_BITS);
- rc_bit_tree_decode(rc, prob, LZMA_NUM_POS_SLOT_BITS,
- &pos_slot);
+ rc_bit_tree_decode(rc, prob3,
+ LZMA_NUM_POS_SLOT_BITS, &pos_slot);
+ rep0 = pos_slot;
if (pos_slot >= LZMA_START_POS_MODEL_INDEX) {
- num_bits = (pos_slot >> 1) - 1;
+ int i2, mi2, num_bits2 = (pos_slot >> 1) - 1;
rep0 = 2 | (pos_slot & 1);
if (pos_slot < LZMA_END_POS_MODEL_INDEX) {
- rep0 <<= num_bits;
- prob = p + LZMA_SPEC_POS + rep0 - pos_slot - 1;
+ rep0 <<= num_bits2;
+ prob3 = p + LZMA_SPEC_POS + rep0 - pos_slot - 1;
} else {
- num_bits -= LZMA_NUM_ALIGN_BITS;
- while (num_bits--)
+ for (; num_bits2 != LZMA_NUM_ALIGN_BITS; num_bits2--)
rep0 = (rep0 << 1) | rc_direct_bit(rc);
- prob = p + LZMA_ALIGN;
rep0 <<= LZMA_NUM_ALIGN_BITS;
- num_bits = LZMA_NUM_ALIGN_BITS;
+ prob3 = p + LZMA_ALIGN;
}
- i = 1;
- mi = 1;
- while (num_bits--) {
- if (rc_get_bit(rc, prob + mi, &mi))
- rep0 |= i;
- i <<= 1;
+ i2 = 1;
+ mi2 = 1;
+ while (num_bits2--) {
+ if (rc_get_bit(rc, prob3 + mi2, &mi2))
+ rep0 |= i2;
+ i2 <<= 1;
}
- } else
- rep0 = pos_slot;
+ }
if (++rep0 == 0)
break;
}
@@ -470,7 +432,7 @@ unpack_lzma_stream(int src_fd, int dst_fd)
len += LZMA_MATCH_MIN_LEN;
IF_NOT_FEATURE_LZMA_FAST(string:)
do {
- pos = buffer_pos - rep0;
+ uint32_t pos = buffer_pos - rep0;
while (pos >= header.dict_size)
pos += header.dict_size;
previous_byte = buffer[pos];