A few minor compressor cleanups

[wimlib] / src / lzms-compress.c

diff --git a/src/lzms-compress.c b/src/lzms-compress.c
index fb1f777ac6b5c3adeb69c1a8bf7508e603baf92f..00c8f5df2058a1f69715b971ef391155a6895fad 100644 (file)
--- a/src/lzms-compress.c
+++ b/src/lzms-compress.c
@@ -716,7 +716,7 @@ lzms_do_init_rc_costs(void)
                for (u32 j = 0; j < LZMS_COST_SHIFT; j++) {
                        w *= w;
                        bit_count <<= 1;
                for (u32 j = 0; j < LZMS_COST_SHIFT; j++) {
                        w *= w;
                        bit_count <<= 1;

-                       while (w >= (1U << 16)) {
+                       while (w >= ((u32)1 << 16)) {

                                w >>= 1;
                                ++bit_count;
                        }
                                w >>= 1;
                                ++bit_count;
                        }


@@ -888,8 +888,7 @@ lzms_consider_lz_explicit_offset_matches(const struct lzms_compressor *c,
        len = 2;
        i = 0;
        do {
        len = 2;
        i = 0;
        do {

-               position_cost = base_cost + lzms_lz_offset_cost(c,
-                                                               matches[i].offset);
+               position_cost = base_cost + lzms_lz_offset_cost(c, matches[i].offset);

                do {
                        cost = position_cost + lzms_fast_length_cost(c, len);
                        if (cost < (cur_optimum_ptr + len)->cost) {
                do {
                        cost = position_cost + lzms_fast_length_cost(c, len);
                        if (cost < (cur_optimum_ptr + len)->cost) {


@@ -1218,8 +1217,8 @@ begin:
                 *      the parser will not go too long without updating the
                 *      probability tables.
                 *
                 *      the parser will not go too long without updating the
                 *      probability tables.
                 *

-                * Note: no check for end-of-block is needed because
-                * end-of-block will trigger condition (1).
+                * Note: no check for end-of-window is needed because
+                * end-of-window will trigger condition (1).

                 */
                if (cur_optimum_ptr == end_optimum_ptr ||
                    cur_optimum_ptr == c->optimum_end)
                 */
                if (cur_optimum_ptr == end_optimum_ptr ||
                    cur_optimum_ptr == c->optimum_end)


@@ -1376,26 +1375,26 @@ lzms_finalize(struct lzms_compressor *c, u8 *cdata, size_t csize_avail)
  * maximum window size.  */
 static void
 lzms_build_params(unsigned int compression_level,
  * maximum window size.  */
 static void
 lzms_build_params(unsigned int compression_level,

-                 struct lzms_compressor_params *lzms_params)
+                 struct lzms_compressor_params *params)

 {
        /* Allow length 2 matches if the compression level is sufficiently high.
         */
        if (compression_level >= 45)
 {
        /* Allow length 2 matches if the compression level is sufficiently high.
         */
        if (compression_level >= 45)

-               lzms_params->min_match_length = 2;
+               params->min_match_length = 2;

        else
        else

-               lzms_params->min_match_length = 3;
+               params->min_match_length = 3;

 
        /* Scale nice_match_length and max_search_depth with the compression
         * level.  But to allow an optimization on length cost calculations,
         * don't allow nice_match_length to exceed LZMS_NUM_FAST_LENGTH.  */
 
        /* Scale nice_match_length and max_search_depth with the compression
         * level.  But to allow an optimization on length cost calculations,
         * don't allow nice_match_length to exceed LZMS_NUM_FAST_LENGTH.  */

-       lzms_params->nice_match_length = ((u64)compression_level * 32) / 50;
-       if (lzms_params->nice_match_length < lzms_params->min_match_length)
-               lzms_params->nice_match_length = lzms_params->min_match_length;
-       if (lzms_params->nice_match_length > LZMS_NUM_FAST_LENGTHS)
-               lzms_params->nice_match_length = LZMS_NUM_FAST_LENGTHS;
-       lzms_params->max_search_depth = compression_level;
-
-       lzms_params->optim_array_length = 1024;
+       params->nice_match_length = ((u64)compression_level * 32) / 50;
+       if (params->nice_match_length < params->min_match_length)
+               params->nice_match_length = params->min_match_length;
+       if (params->nice_match_length > LZMS_NUM_FAST_LENGTHS)
+               params->nice_match_length = LZMS_NUM_FAST_LENGTHS;
+       params->max_search_depth = compression_level;
+
+       params->optim_array_length = 1024;

 }
 
 /* Given the internal compression parameters and maximum window size, build the
 }
 
 /* Given the internal compression parameters and maximum window size, build the