diff --git a/lib/compress/zstd_lazy.c b/lib/compress/zstd_lazy.c index e9f5e1d35..77b0b8bcf 100644 --- a/lib/compress/zstd_lazy.c +++ b/lib/compress/zstd_lazy.c @@ -573,21 +573,22 @@ size_t ZSTD_compressBlock_lazy_generic( size_t offset=0; const BYTE* start=ip+1; - const U32 repIndex = (U32)(ip - base) + 1 - offset_1; - const BYTE* repMatch = (dictMode == ZSTD_dictMatchState - && repIndex < prefixLowestIndex) ? - dictBase + (repIndex - dictIndexDelta) : - base + repIndex; - /* check repCode */ - if (dictMode == ZSTD_dictMatchState - && ((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) - && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) { - const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; - matchLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; - if (depth==0) goto _storeSequence; - } else if ( dictMode == ZSTD_noDict - && ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1)))) { + if (dictMode == ZSTD_dictMatchState) { + const U32 repIndex = (U32)(ip - base) + 1 - offset_1; + const BYTE* repMatch = (dictMode == ZSTD_dictMatchState + && repIndex < prefixLowestIndex) ? + dictBase + (repIndex - dictIndexDelta) : + base + repIndex; + if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) + && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) { + const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; + matchLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; + if (depth==0) goto _storeSequence; + } + } + if ( dictMode == ZSTD_noDict + && ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1)))) { matchLength = ZSTD_count(ip+1+4, ip+1+4-offset_1, iend) + 4; if (depth==0) goto _storeSequence; } @@ -608,13 +609,29 @@ size_t ZSTD_compressBlock_lazy_generic( if (depth>=1) while (ip0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) { + if ( (dictMode == ZSTD_noDict) + && (offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) { size_t const mlRep = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4; int const gain2 = (int)(mlRep * 3); int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1); if ((mlRep >= 4) && (gain2 > gain1)) matchLength = mlRep, offset = 0, start = ip; } + if (dictMode == ZSTD_dictMatchState) { + const U32 repIndex = (U32)(ip - base) - offset_1; + const BYTE* repMatch = repIndex < prefixLowestIndex ? + dictBase + (repIndex - dictIndexDelta) : + base + repIndex; + if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) + && (MEM_read32(repMatch) == MEM_read32(ip)) ) { + const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; + size_t const mlRep = ZSTD_count_2segments(ip+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; + int const gain2 = (int)(mlRep * 3); + int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1); + if ((mlRep >= 4) && (gain2 > gain1)) + matchLength = mlRep, offset = 0, start = ip; + } + } { size_t offset2=99999999; size_t const ml2 = searchMax(ms, cParams, ip, iend, &offset2); int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */ @@ -627,12 +644,28 @@ size_t ZSTD_compressBlock_lazy_generic( /* let's find an even better one */ if ((depth==2) && (ip0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) { - size_t const ml2 = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4; - int const gain2 = (int)(ml2 * 4); + if ( (dictMode == ZSTD_noDict) + && (offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) { + size_t const mlRep = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4; + int const gain2 = (int)(mlRep * 4); int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1); - if ((ml2 >= 4) && (gain2 > gain1)) - matchLength = ml2, offset = 0, start = ip; + if ((mlRep >= 4) && (gain2 > gain1)) + matchLength = mlRep, offset = 0, start = ip; + } + if (dictMode == ZSTD_dictMatchState) { + const U32 repIndex = (U32)(ip - base) - offset_1; + const BYTE* repMatch = repIndex < prefixLowestIndex ? + dictBase + (repIndex - dictIndexDelta) : + base + repIndex; + if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) + && (MEM_read32(repMatch) == MEM_read32(ip)) ) { + const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; + size_t const mlRep = ZSTD_count_2segments(ip+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; + int const gain2 = (int)(mlRep * 4); + int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1); + if ((mlRep >= 4) && (gain2 > gain1)) + matchLength = mlRep, offset = 0, start = ip; + } } { size_t offset2=99999999; size_t const ml2 = searchMax(ms, cParams, ip, iend, &offset2); @@ -668,15 +701,15 @@ _storeSequence: if (dictMode == ZSTD_dictMatchState) { while (ip <= ilimit) { U32 const current2 = (U32)(ip-base); - U32 const repIndex2 = current2 - offset_2; - const BYTE* repMatch2 = dictMode == ZSTD_dictMatchState - && repIndex2 < prefixLowestIndex ? - dictBase - dictIndexDelta + repIndex2 : - base + repIndex2; - if ( ((U32)((prefixLowestIndex-1) - (U32)repIndex2) >= 3 /* intentional overflow */) - && (MEM_read32(repMatch2) == MEM_read32(ip)) ) { - const BYTE* const repEnd2 = repIndex2 < prefixLowestIndex ? dictEnd : iend; - matchLength = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixLowest) + 4; + U32 const repIndex = current2 - offset_2; + const BYTE* repMatch = dictMode == ZSTD_dictMatchState + && repIndex < prefixLowestIndex ? + dictBase - dictIndexDelta + repIndex : + base + repIndex; + if ( ((U32)((prefixLowestIndex-1) - (U32)repIndex) >= 3 /* intentional overflow */) + && (MEM_read32(repMatch) == MEM_read32(ip)) ) { + const BYTE* const repEnd2 = repIndex < prefixLowestIndex ? dictEnd : iend; + matchLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd2, prefixLowest) + 4; offset = offset_2; offset_2 = offset_1; offset_1 = offset; /* swap offset_2 <=> offset_1 */ ZSTD_storeSeq(seqStore, 0, anchor, 0, matchLength-MINMATCH); ip += matchLength;