Merging upstream version 1.16~pre1.

Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>

1 files changed, 41 insertions, 78 deletions

diff --git a/fast_encoder.cc b/fast_encoder.cc
index dfbb429..f87fdec 100644
--- a/fast_encoder.cc
+++ b/fast_encoder.cc
@@ -1,5 +1,6 @@
 /*  Lzip - LZMA lossless data compressor
-    Copyright (C) 2008, 2009, 2010, 2011, 2012, 2013 Antonio Diaz Diaz.
+    Copyright (C) 2008, 2009, 2010, 2011, 2012, 2013, 2014
+    Antonio Diaz Diaz.
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -32,37 +33,35 @@
 
 int Fmatchfinder::longest_match_len( int * const distance )
   {
-  int len_limit = match_len_limit_;
-  if( len_limit > available_bytes() )
-    {
-    len_limit = available_bytes();
-    if( len_limit < 4 ) return 0;
-    }
+  if( len_limit > available_bytes() ) return 0;
 
-  key4 = ( ( key4 << 4 ) ^ buffer[pos+3] ) & key4_mask;
+  const uint8_t * const data = buffer + pos;
+  key4 = ( ( key4 << 4 ) ^ data[3] ) & key4_mask;
 
+  const int pos1 = pos + 1;
   int newpos = prev_positions[key4];
-  prev_positions[key4] = pos;
+  prev_positions[key4] = pos1;
 
   int32_t * ptr0 = pos_array + cyclic_pos;
   int maxlen = 0;
 
   for( int count = 4; ; )
     {
-    const int delta = pos - newpos;
-    if( delta > dictionary_size_ || newpos < 0 || --count < 0 )
-      { *ptr0 = -1; break; }
-    int len = 0;
-    if( buffer[maxlen+newpos] == buffer[maxlen+pos] )
-      while( len < len_limit && buffer[len+newpos] == buffer[len+pos] ) ++len;
-
-    if( maxlen < len ) { maxlen = len; *distance = delta - 1; }
-
+    if( --count < 0 || newpos <= 0 ) { *ptr0 = 0; break; }
+    const int delta = pos1 - newpos;
+    if( delta > dictionary_size_ ) { *ptr0 = 0; break; }
     int32_t * const newptr = pos_array +
       ( cyclic_pos - delta +
           ( ( cyclic_pos >= delta ) ? 0 : dictionary_size_ + 1 ) );
 
-    if( len < len_limit )
+    if( data[maxlen-delta] == data[maxlen] )
+      {
+      int len = 0;
+      while( len < len_limit && data[len-delta] == data[len] ) ++len;
+      if( maxlen < len ) { maxlen = len; *distance = delta - 1; }
+      }
+
+    if( maxlen < len_limit )
       {
       *ptr0 = newpos;
       ptr0 = newptr;
@@ -71,54 +70,19 @@ int Fmatchfinder::longest_match_len( int * const distance )
     else
       {
       *ptr0 = *newptr;
+      maxlen += true_match_len( maxlen, *distance + 1, max_match_len - maxlen );
       break;
       }
     }
-  if( maxlen == match_len_limit_ && maxlen < max_match_len )
-    maxlen += true_match_len( maxlen, *distance + 1, max_match_len - maxlen );
   return maxlen;
   }
 
 
-void Fmatchfinder::longest_match_len( int n )
-  {
-  while( --n >= 0 )
-    {
-    int len_limit = match_len_limit_ - 1;		// len_limit - 1
-    if( len_limit >= available_bytes() )
-      {
-      len_limit = available_bytes() - 1;
-      if( len_limit < 3 ) { move_pos(); continue; }
-      }
-
-    key4 = ( ( key4 << 4 ) ^ buffer[pos+3] ) & key4_mask;
-
-    const int newpos = prev_positions[key4];
-    prev_positions[key4] = pos;
-
-    int32_t * const ptr0 = pos_array + cyclic_pos;
-
-    if( pos - newpos > dictionary_size_ || newpos < 0 )
-      *ptr0 = -1;
-    else if( buffer[len_limit+newpos] != buffer[len_limit+pos] ||
-             std::memcmp( buffer + newpos, buffer + pos, len_limit ) != 0 )
-      *ptr0 = newpos;
-    else
-      {
-      int idx = cyclic_pos - pos + newpos;
-      if( idx < 0 ) idx += dictionary_size_ + 1;
-      *ptr0 = pos_array[idx];
-      }
-    move_pos();
-    }
-  }
-
-
 bool FLZ_encoder::encode_member( const unsigned long long member_size )
   {
   const unsigned long long member_size_limit =
     member_size - File_trailer::size() - max_marker_size;
-  int dis = 0;
+  int rep = 0;
   int reps[num_rep_distances];
   State state;
   for( int i = 0; i < num_rep_distances; ++i ) reps[i] = 0;
@@ -134,7 +98,7 @@ bool FLZ_encoder::encode_member( const unsigned long long member_size )
     renc.encode_bit( bm_match[state()][0], 0 );
     encode_literal( prev_byte, cur_byte );
     crc32.update_byte( crc_, cur_byte );
-    fmatchfinder.longest_match_len( 1 );
+    fmatchfinder.update_and_move( 1 );
     }
 
   while( !fmatchfinder.finished() &&
@@ -149,52 +113,51 @@ bool FLZ_encoder::encode_member( const unsigned long long member_size )
       {
       const int tlen =
         fmatchfinder.true_match_len( 0, reps[i] + 1, max_match_len );
-      if( tlen > len ) { len = tlen; dis = i; }
+      if( tlen > len ) { len = tlen; rep = i; }
       }
-    if( len > min_match_len && len + 4 > main_len )
+    if( len > min_match_len && len + 3 > main_len )
       {
       crc32.update_buf( crc_, fmatchfinder.ptr_to_current_pos(), len );
       renc.encode_bit( bm_match[state()][pos_state], 1 );
       renc.encode_bit( bm_rep[state()], 1 );
-      const bool bit = ( dis == 0 );
-      renc.encode_bit( bm_rep0[state()], !bit );
-      if( bit )
+      renc.encode_bit( bm_rep0[state()], rep != 0 );
+      if( rep == 0 )
         renc.encode_bit( bm_len[state()][pos_state], 1 );
       else
         {
-        const int distance = reps[dis];
-        for( int i = dis; i > 0; --i ) reps[i] = reps[i-1];
+        renc.encode_bit( bm_rep1[state()], rep > 1 );
+        if( rep > 1 )
+          renc.encode_bit( bm_rep2[state()], rep > 2 );
+        const int distance = reps[rep];
+        for( int i = rep; i > 0; --i ) reps[i] = reps[i-1];
         reps[0] = distance;
-        renc.encode_bit( bm_rep1[state()], dis > 1 );
-        if( dis > 1 )
-          renc.encode_bit( bm_rep2[state()], dis > 2 );
         }
-      rep_len_encoder.encode( renc, len, pos_state );
       state.set_rep();
-      move_pos( len );
+      rep_len_encoder.encode( renc, len, pos_state );
+      fmatchfinder.move_pos();
+      fmatchfinder.update_and_move( len - 1 );
       continue;
       }
 
-    if( main_len > min_match_len ||
-        ( main_len == min_match_len && match_distance < modeled_distances ) )
+    if( main_len > min_match_len )
       {
       crc32.update_buf( crc_, fmatchfinder.ptr_to_current_pos(), main_len );
-      dis = match_distance;
       renc.encode_bit( bm_match[state()][pos_state], 1 );
       renc.encode_bit( bm_rep[state()], 0 );
-      encode_pair( dis, main_len, pos_state );
       state.set_match();
-      move_pos( main_len );
       for( int i = num_rep_distances - 1; i > 0; --i ) reps[i] = reps[i-1];
-      reps[0] = dis;
+      reps[0] = match_distance;
+      encode_pair( match_distance, main_len, pos_state );
+      fmatchfinder.move_pos();
+      fmatchfinder.update_and_move( main_len - 1 );
       continue;
       }
 
-    const uint8_t prev_byte = fmatchfinder[-1];
+    const uint8_t prev_byte = fmatchfinder[1];
     const uint8_t cur_byte = fmatchfinder[0];
-    const uint8_t match_byte = fmatchfinder[-reps[0]-1];
-    crc32.update_byte( crc_, cur_byte );
+    const uint8_t match_byte = fmatchfinder[reps[0]+1];
     fmatchfinder.move_pos();
+    crc32.update_byte( crc_, cur_byte );
 
     if( match_byte == cur_byte )
       {