]> wimlib.net Git - wimlib/blobdiff - src/lzx_compress.c
lzx_compress.c: CAN_BUFFER() was 1 off
[wimlib] / src / lzx_compress.c
index de89f596c1dc70fc63adac9e211541634a535757..cc43fd6cc79ddf07eab9b067589a531e08b1c9a1 100644 (file)
@@ -548,7 +548,7 @@ struct lzx_output_bitstream {
 
 /* Can the specified number of bits always be added to 'bitbuf' after any
  * pending 16-bit coding units have been flushed?  */
-#define CAN_BUFFER(n)  ((n) <= (8 * sizeof(machine_word_t)) - 16)
+#define CAN_BUFFER(n)  ((n) <= (8 * sizeof(machine_word_t)) - 15)
 
 /*
  * Initialize the output bitstream.
@@ -994,6 +994,8 @@ lzx_write_sequences(struct lzx_output_bitstream *os, int block_type,
                        if (!CAN_BUFFER(MAX_MATCH_BITS))
                                lzx_flush_bits(os, ALIGNED_CODEWORD_LIMIT);
                } else {
+                       STATIC_ASSERT(CAN_BUFFER(17));
+
                        lzx_add_bits(os, extra_bits, num_extra_bits);
                        if (!CAN_BUFFER(MAX_MATCH_BITS))
                                lzx_flush_bits(os, 17);
@@ -1709,15 +1711,21 @@ lzx_update_costs(struct lzx_compressor *c)
        unsigned i;
        const struct lzx_lens *lens = &c->codes[c->codes_index].lens;
 
-       for (i = 0; i < c->num_main_syms; i++)
-               c->costs.main[i] = (lens->main[i] ? lens->main[i] : 15) * LZX_BIT_COST;
+       for (i = 0; i < c->num_main_syms; i++) {
+               c->costs.main[i] = (lens->main[i] ? lens->main[i] :
+                                   MAIN_CODEWORD_LIMIT) * LZX_BIT_COST;
+       }
 
-       for (i = 0; i < LZX_LENCODE_NUM_SYMBOLS; i++)
-               c->costs.len[i] = (lens->len[i] ? lens->len[i] : 15) * LZX_BIT_COST;
+       for (i = 0; i < LZX_LENCODE_NUM_SYMBOLS; i++) {
+               c->costs.len[i] = (lens->len[i] ? lens->len[i] :
+                                  LENGTH_CODEWORD_LIMIT) * LZX_BIT_COST;
+       }
 
 #if LZX_CONSIDER_ALIGNED_COSTS
-       for (i = 0; i < LZX_ALIGNEDCODE_NUM_SYMBOLS; i++)
-               c->costs.aligned[i] = (lens->aligned[i] ? lens->aligned[i] : 7) * LZX_BIT_COST;
+       for (i = 0; i < LZX_ALIGNEDCODE_NUM_SYMBOLS; i++) {
+               c->costs.aligned[i] = (lens->aligned[i] ? lens->aligned[i] :
+                                      ALIGNED_CODEWORD_LIMIT) * LZX_BIT_COST;
+       }
 #endif
 
        lzx_compute_match_costs(c);
@@ -1803,7 +1811,7 @@ lzx_compress_near_optimal(struct lzx_compressor *c,
                        if (unlikely(max_len > in_end - in_next)) {
                                max_len = in_end - in_next;
                                nice_len = min(max_len, nice_len);
-                               if (unlikely(max_len < 5)) {
+                               if (unlikely(max_len < BT_MATCHFINDER_REQUIRED_NBYTES)) {
                                        in_next++;
                                        cache_ptr->length = 0;
                                        cache_ptr++;
@@ -1843,7 +1851,7 @@ lzx_compress_near_optimal(struct lzx_compressor *c,
                                        if (unlikely(max_len > in_end - in_next)) {
                                                max_len = in_end - in_next;
                                                nice_len = min(max_len, nice_len);
-                                               if (unlikely(max_len < 5)) {
+                                               if (unlikely(max_len < BT_MATCHFINDER_REQUIRED_NBYTES)) {
                                                        in_next++;
                                                        cache_ptr->length = 0;
                                                        cache_ptr++;
@@ -2257,8 +2265,8 @@ lzx_create_compressor(size_t max_bufsize, unsigned compression_level,
                        c->impl = lzx_compress_lazy_16;
                else
                        c->impl = lzx_compress_lazy_32;
-               c->max_search_depth = (36 * compression_level) / 20;
-               c->nice_match_length = (72 * compression_level) / 20;
+               c->max_search_depth = (60 * compression_level) / 20;
+               c->nice_match_length = (80 * compression_level) / 20;
 
                /* lzx_compress_lazy() needs max_search_depth >= 2 because it
                 * halves the max_search_depth when attempting a lazy match, and
@@ -2277,7 +2285,7 @@ lzx_create_compressor(size_t max_bufsize, unsigned compression_level,
                /* Scale nice_match_length and max_search_depth with the
                 * compression level.  */
                c->max_search_depth = (24 * compression_level) / 50;
-               c->nice_match_length = (32 * compression_level) / 50;
+               c->nice_match_length = (48 * compression_level) / 50;
 
                /* Set a number of optimization passes appropriate for the
                 * compression level.  */
@@ -2338,7 +2346,7 @@ lzx_compress(const void *restrict in, size_t in_nbytes,
        else
                memcpy(c->in_buffer, in, in_nbytes);
        c->in_nbytes = in_nbytes;
-       lzx_do_e8_preprocessing(c->in_buffer, in_nbytes);
+       lzx_preprocess(c->in_buffer, in_nbytes);
 
        /* Initially, the previous Huffman codeword lengths are all zeroes.  */
        c->codes_index = 0;
@@ -2353,7 +2361,7 @@ lzx_compress(const void *restrict in, size_t in_nbytes,
        /* Flush the output bitstream and return the compressed size or 0.  */
        result = lzx_flush_output(&os);
        if (!result && c->destructive)
-               lzx_undo_e8_preprocessing(c->in_buffer, c->in_nbytes);
+               lzx_postprocess(c->in_buffer, c->in_nbytes);
        return result;
 }