Factor out lz_repsearch() and also use for LZMS

[wimlib] / src / lzms-compress.c

diff --git a/src/lzms-compress.c b/src/lzms-compress.c
index 21c82ea87bf9f93e2005406018960f73bb6488f6..8ad19bc0d1cb2820524d4cde3b6f680b3bb45326 100644 (file)
--- a/src/lzms-compress.c
+++ b/src/lzms-compress.c
@@ -41,6 +41,7 @@
 #include "wimlib/endianness.h"
 #include "wimlib/error.h"
 #include "wimlib/lz_mf.h"
+#include "wimlib/lz_repsearch.h"
 #include "wimlib/lzms.h"
 #include "wimlib/util.h"
 
@@ -840,6 +841,20 @@ lzms_get_lz_match_cost(struct lzms_compressor *ctx,
               lzms_get_length_cost(&ctx->length_encoder, length);
 }
 
+static inline u32
+lzms_repsearch(const u8 * const strptr, const u32 bytes_remaining,
+              const struct lzms_lz_lru_queues *queue, u32 *offset_ret)
+{
+       u32 len;
+       unsigned slot = 0;
+
+       len = lz_repsearch(strptr, bytes_remaining, UINT32_MAX,
+                          queue->recent_offsets, LZMS_NUM_RECENT_OFFSETS, &slot);
+       *offset_ret = queue->recent_offsets[slot];
+       return len;
+}
+
+
 static struct lz_match
 lzms_match_chooser_reverse_list(struct lzms_compressor *ctx, unsigned cur_pos)
 {
@@ -899,21 +914,12 @@ lzms_get_near_optimal_item(struct lzms_compressor *ctx)
        ctx->optimum_cur_idx = 0;
        ctx->optimum_end_idx = 0;
 
-       longest_rep_len = ctx->params.min_match_length - 1;
        if (lz_mf_get_position(ctx->mf) >= LZMS_MAX_INIT_RECENT_OFFSET) {
-               u32 limit = lz_mf_get_bytes_remaining(ctx->mf);
-               for (int i = 0; i < LZMS_NUM_RECENT_OFFSETS; i++) {
-                       u32 offset = ctx->lru.lz.recent_offsets[i];
-                       const u8 *strptr = lz_mf_get_window_ptr(ctx->mf);
-                       const u8 *matchptr = strptr - offset;
-                       u32 len = 0;
-                       while (len < limit && strptr[len] == matchptr[len])
-                               len++;
-                       if (len > longest_rep_len) {
-                               longest_rep_len = len;
-                               longest_rep_offset = offset;
-                       }
-               }
+               longest_rep_len = lzms_repsearch(lz_mf_get_window_ptr(ctx->mf),
+                                                lz_mf_get_bytes_remaining(ctx->mf),
+                                                &ctx->lru.lz, &longest_rep_offset);
+       } else {
+               longest_rep_len = 0;
        }
 
        if (longest_rep_len >= ctx->params.nice_match_length) {
@@ -972,7 +978,7 @@ lzms_get_near_optimal_item(struct lzms_compressor *ctx)
        }
        end_pos = longest_len;
 
-       if (longest_rep_len >= ctx->params.min_match_length) {
+       if (longest_rep_len) {
                struct lzms_adaptive_state state;
                u32 cost;
 
@@ -1002,21 +1008,13 @@ lzms_get_near_optimal_item(struct lzms_compressor *ctx)
                if (cur_pos == end_pos || cur_pos == ctx->params.optim_array_length)
                        return lzms_match_chooser_reverse_list(ctx, cur_pos);
 
-               longest_rep_len = ctx->params.min_match_length - 1;
                if (lz_mf_get_position(ctx->mf) >= LZMS_MAX_INIT_RECENT_OFFSET) {
-                       u32 limit = lz_mf_get_bytes_remaining(ctx->mf);
-                       for (int i = 0; i < LZMS_NUM_RECENT_OFFSETS; i++) {
-                               u32 offset = ctx->optimum[cur_pos].state.lru.recent_offsets[i];
-                               const u8 *strptr = lz_mf_get_window_ptr(ctx->mf);
-                               const u8 *matchptr = strptr - offset;
-                               u32 len = 0;
-                               while (len < limit && strptr[len] == matchptr[len])
-                                       len++;
-                               if (len > longest_rep_len) {
-                                       longest_rep_len = len;
-                                       longest_rep_offset = offset;
-                               }
-                       }
+                       longest_rep_len = lzms_repsearch(lz_mf_get_window_ptr(ctx->mf),
+                                                        lz_mf_get_bytes_remaining(ctx->mf),
+                                                        &ctx->optimum[cur_pos].state.lru,
+                                                        &longest_rep_offset);
+               } else {
+                       longest_rep_len = 0;
                }
 
                if (longest_rep_len >= ctx->params.nice_match_length) {