lz4opt: simplified match finder invocation to LZ4HC_FindLongerMatch()

1 files changed, 11 insertions, 20 deletions

diff --git a/lib/lz4opt.h b/lib/lz4opt.h
index 03ab825..6db8586 100644
--- a/lib/lz4opt.h
+++ b/lib/lz4opt.h
@@ -70,32 +70,23 @@ LZ4_FORCE_INLINE int LZ4HC_sequencePrice(int litlen, int mlen)
 /*-*************************************
 *  Match finder
 ***************************************/
-
-LZ4_FORCE_INLINE
-int LZ4HC_FindLongerMatch(LZ4HC_CCtx_internal* const ctx,   /* Index table will be updated */
-                        const BYTE* const ip, const BYTE* const iHighLimit,
-                        int longest,
-                        const BYTE** matchpos,
-                        const int maxNbAttempts)
-{
-    const BYTE* uselessPtr = ip;
-    return LZ4HC_InsertAndGetWiderMatch(ctx, ip, ip, iHighLimit, longest, matchpos, &uselessPtr, maxNbAttempts);
-}
-
 typedef struct {
     int off;
     int len;
 } LZ4HC_match_t;
 
 LZ4_FORCE_INLINE
-LZ4HC_match_t LZ4HC_HashChain_GetAllMatches (LZ4HC_CCtx_internal* const ctx,
-                        const BYTE* const ip, const BYTE* const iHighLimit,
-                        size_t best_mlen, int nbSearches)
+LZ4HC_match_t LZ4HC_FindLongerMatch(LZ4HC_CCtx_internal* const ctx,
+                        const BYTE* ip, const BYTE* const iHighLimit,
+                        int minLen, int nbSearches)
 {
     LZ4HC_match_t match = { 0 , 0 };
     const BYTE* matchPtr = NULL;
-    int matchLength = LZ4HC_FindLongerMatch(ctx, ip, iHighLimit, (int)best_mlen, &matchPtr, nbSearches);
-    if ((size_t)matchLength <= best_mlen) return match;
+    /* note : LZ4HC_InsertAndGetWiderMatch() is able to modify the starting position of a match (*startpos),
+     * but this won't be the case here, as we define iLowLimit==ip,
+     * so LZ4HC_InsertAndGetWiderMatch() won't be allowed to search past ip */
+    int const matchLength = LZ4HC_InsertAndGetWiderMatch(ctx, ip, ip, iHighLimit, minLen, &matchPtr, &ip, nbSearches);
+    if (matchLength <= minLen) return match;
     match.len = matchLength;
     match.off = (int)(ip-matchPtr);
     return match;
@@ -135,7 +126,7 @@ static int LZ4HC_compress_optimal (
         int best_mlen, best_off;
         int cur, last_match_pos = 0;
 
-        LZ4HC_match_t const firstMatch = LZ4HC_HashChain_GetAllMatches(ctx, ip, matchlimit, MINMATCH-1, nbSearches);
+        LZ4HC_match_t const firstMatch = LZ4HC_FindLongerMatch(ctx, ip, matchlimit, MINMATCH-1, nbSearches);
         if (firstMatch.len==0) { ip++; continue; }
 
         if ((size_t)firstMatch.len > sufficient_len) {
@@ -199,10 +190,10 @@ static int LZ4HC_compress_optimal (
 
             DEBUGLOG(7, "search at rPos:%u", cur);
             if (fullUpdate)
-                newMatch = LZ4HC_HashChain_GetAllMatches(ctx, curPtr, matchlimit, MINMATCH-1, nbSearches);
+                newMatch = LZ4HC_FindLongerMatch(ctx, curPtr, matchlimit, MINMATCH-1, nbSearches);
             else
                 /* only test matches of minimum length; slightly faster, but misses a few bytes */
-                newMatch = LZ4HC_HashChain_GetAllMatches(ctx, curPtr, matchlimit, last_match_pos - cur, nbSearches);
+                newMatch = LZ4HC_FindLongerMatch(ctx, curPtr, matchlimit, last_match_pos - cur, nbSearches);
             if (!newMatch.len) continue;
 
             if ( ((size_t)newMatch.len > sufficient_len)