diff --git a/.gitignore b/.gitignore index 0c840b6b..4c297053 100644 --- a/.gitignore +++ b/.gitignore @@ -14,7 +14,7 @@ *.dylib # Executables -zstd. +/zstd zstdmt *.exe *.out diff --git a/lib/compress/zstd_double_fast.c b/lib/compress/zstd_double_fast.c index f156da9d..5957255d 100644 --- a/lib/compress/zstd_double_fast.c +++ b/lib/compress/zstd_double_fast.c @@ -254,11 +254,14 @@ _match_stored: anchor = ip; if (ip <= ilimit) { - /* Fill Table */ - hashLong[ZSTD_hashPtr(base+current+2, hBitsL, 8)] = - hashSmall[ZSTD_hashPtr(base+current+2, hBitsS, mls)] = current+2; /* here because current+2 could be > iend-8 */ - hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = - hashSmall[ZSTD_hashPtr(ip-2, hBitsS, mls)] = (U32)(ip-2-base); + /* Complementary insertion */ + /* done after iLimit test, as candidates could be > iend-8 */ + { U32 const indexToInsert = current+2; + hashLong[ZSTD_hashPtr(base+indexToInsert, hBitsL, 8)] = indexToInsert; + hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base); + hashSmall[ZSTD_hashPtr(base+indexToInsert, hBitsS, mls)] = indexToInsert; + hashSmall[ZSTD_hashPtr(ip-1, hBitsS, mls)] = (U32)(ip-1-base); + } /* check immediate repcode */ if (dictMode == ZSTD_dictMatchState) { @@ -452,16 +455,20 @@ static size_t ZSTD_compressBlock_doubleFast_extDict_generic( continue; } } - /* found a match : store it */ + /* move to next sequence start */ ip += mLength; anchor = ip; if (ip <= ilimit) { - /* Fill Table */ - hashSmall[ZSTD_hashPtr(base+current+2, hBitsS, mls)] = current+2; - hashLong[ZSTD_hashPtr(base+current+2, hBitsL, 8)] = current+2; - hashSmall[ZSTD_hashPtr(ip-2, hBitsS, mls)] = (U32)(ip-2-base); - hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base); + /* Complementary insertion */ + /* done after iLimit test, as candidates could be > iend-8 */ + { U32 const indexToInsert = current+2; + hashLong[ZSTD_hashPtr(base+indexToInsert, hBitsL, 8)] = indexToInsert; + hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base); + hashSmall[ZSTD_hashPtr(base+indexToInsert, hBitsS, mls)] = indexToInsert; + hashSmall[ZSTD_hashPtr(ip-1, hBitsS, mls)] = (U32)(ip-1-base); + } + /* check immediate repcode */ while (ip <= ilimit) { U32 const current2 = (U32)(ip-base);