From c3fff877e1c7c3f2aff2833d5f5e5b7adc95ecd6 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sun, 2 Mar 2008 18:55:49 +0000 Subject: unlzma: if !LZMA_FAST, save ~200 more bytes (Pascal Bellard ) --- archival/libunarchive/decompress_unlzma.c | 60 ++++++++++++++++++------------- 1 file changed, 36 insertions(+), 24 deletions(-) diff --git a/archival/libunarchive/decompress_unlzma.c b/archival/libunarchive/decompress_unlzma.c index 4f36c060f..5bf4de2bd 100644 --- a/archival/libunarchive/decompress_unlzma.c +++ b/archival/libunarchive/decompress_unlzma.c @@ -282,14 +282,16 @@ 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; - prob = - p + LZMA_IS_MATCH + (state << LZMA_NUM_POS_BITS_MAX) + pos_state; + 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))))); + prob = (p + LZMA_LITERAL + + (LZMA_LIT_SIZE * ((((buffer_pos + global_pos) & literal_pos_mask) << lc) + + (previous_byte >> (8 - lc)) + ) + ) + ); if (state >= LZMA_NUM_LIT_STATES) { int match_byte; @@ -317,8 +319,15 @@ unpack_lzma_stream(int src_fd, int dst_fd) prob_lit = prob + mi; rc_get_bit(rc, prob_lit, &mi); } - previous_byte = (uint8_t) mi; + state -= 3; + if (state < 4-3) + state = 0; + if (state >= 10-3) + state -= 6-3; + + previous_byte = (uint8_t) mi; +#if ENABLE_FEATURE_LZMA_FAST buffer[buffer_pos++] = previous_byte; if (buffer_pos == header.dict_size) { buffer_pos = 0; @@ -327,12 +336,10 @@ unpack_lzma_stream(int src_fd, int dst_fd) goto bad; USE_DESKTOP(total_written += header.dict_size;) } - if (state < 4) - state = 0; - else if (state < 10) - state -= 3; - else - state -= 6; +#else + len = 1; + goto one_byte; +#endif } else { int offset; uint16_t *prob_len; @@ -352,11 +359,14 @@ unpack_lzma_stream(int src_fd, int dst_fd) if (rc_is_bit_0(rc, prob)) { rc_update_bit_0(rc, prob); prob = (p + LZMA_IS_REP_0_LONG - + (state << LZMA_NUM_POS_BITS_MAX) + pos_state); + + (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 ENABLE_FEATURE_LZMA_FAST pos = buffer_pos - rep0; while (pos >= header.dict_size) pos += header.dict_size; @@ -370,6 +380,10 @@ unpack_lzma_stream(int src_fd, int dst_fd) USE_DESKTOP(total_written += header.dict_size;) } continue; +#else + len = 1; + goto string; +#endif } else { rc_update_bit_1(rc, prob); } @@ -405,7 +419,7 @@ unpack_lzma_stream(int src_fd, int dst_fd) 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)); + + (pos_state << LZMA_LEN_NUM_LOW_BITS)); offset = 0; num_bits = LZMA_LEN_NUM_LOW_BITS; } else { @@ -414,14 +428,14 @@ unpack_lzma_stream(int src_fd, int dst_fd) 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)); + + (pos_state << LZMA_LEN_NUM_MID_BITS)); offset = 1 << LZMA_LEN_NUM_LOW_BITS; num_bits = LZMA_LEN_NUM_MID_BITS; } else { rc_update_bit_1(rc, prob_len); prob_len = prob + LZMA_LEN_HIGH; offset = ((1 << LZMA_LEN_NUM_LOW_BITS) - + (1 << LZMA_LEN_NUM_MID_BITS)); + + (1 << LZMA_LEN_NUM_MID_BITS)); num_bits = LZMA_LEN_NUM_HIGH_BITS; } } @@ -432,12 +446,10 @@ unpack_lzma_stream(int src_fd, int dst_fd) int pos_slot; state += LZMA_NUM_LIT_STATES; - prob = - p + LZMA_POS_SLOT + - ((len < - LZMA_NUM_LEN_TO_POS_STATES ? len : - LZMA_NUM_LEN_TO_POS_STATES - 1) - << LZMA_NUM_POS_SLOT_BITS); + prob = 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); if (pos_slot >= LZMA_START_POS_MODEL_INDEX) { @@ -468,12 +480,13 @@ unpack_lzma_stream(int src_fd, int dst_fd) } len += LZMA_MATCH_MIN_LEN; - + SKIP_FEATURE_LZMA_FAST(string:) do { pos = buffer_pos - rep0; while (pos >= header.dict_size) pos += header.dict_size; previous_byte = buffer[pos]; + SKIP_FEATURE_LZMA_FAST(one_byte:) buffer[buffer_pos++] = previous_byte; if (buffer_pos == header.dict_size) { buffer_pos = 0; @@ -487,7 +500,6 @@ unpack_lzma_stream(int src_fd, int dst_fd) } } - if (full_write(dst_fd, buffer, buffer_pos) != buffer_pos) { bad: rc_free(rc); -- cgit v1.2.3