From: W. Felix Handte Date: Thu, 9 Sep 2021 21:01:31 +0000 (-0400) Subject: Simplify DMS Implementation by Removing noDict Support X-Git-Tag: v1.5.1~1^2~77^2~4 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=62536ef7da6023a1a0d533351b402b5418c4199a;p=thirdparty%2Fzstd.git Simplify DMS Implementation by Removing noDict Support --- diff --git a/lib/compress/zstd_double_fast.c b/lib/compress/zstd_double_fast.c index 380214c57..c58e5cd3f 100644 --- a/lib/compress/zstd_double_fast.c +++ b/lib/compress/zstd_double_fast.c @@ -254,10 +254,10 @@ _match_stored: FORCE_INLINE_TEMPLATE -size_t ZSTD_compressBlock_doubleFast_generic( +size_t ZSTD_compressBlock_doubleFast_dictMatchState_generic( ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], void const* src, size_t srcSize, - U32 const mls /* template */, ZSTD_dictMode_e const dictMode) + U32 const mls /* template */) { ZSTD_compressionParameters const* cParams = &ms->cParams; U32* const hashLong = ms->hashTable; @@ -278,54 +278,30 @@ size_t ZSTD_compressBlock_doubleFast_generic( U32 offsetSaved = 0; const ZSTD_matchState_t* const dms = ms->dictMatchState; - const ZSTD_compressionParameters* const dictCParams = - dictMode == ZSTD_dictMatchState ? - &dms->cParams : NULL; - const U32* const dictHashLong = dictMode == ZSTD_dictMatchState ? - dms->hashTable : NULL; - const U32* const dictHashSmall = dictMode == ZSTD_dictMatchState ? - dms->chainTable : NULL; - const U32 dictStartIndex = dictMode == ZSTD_dictMatchState ? - dms->window.dictLimit : 0; - const BYTE* const dictBase = dictMode == ZSTD_dictMatchState ? - dms->window.base : NULL; - const BYTE* const dictStart = dictMode == ZSTD_dictMatchState ? - dictBase + dictStartIndex : NULL; - const BYTE* const dictEnd = dictMode == ZSTD_dictMatchState ? - dms->window.nextSrc : NULL; - const U32 dictIndexDelta = dictMode == ZSTD_dictMatchState ? - prefixLowestIndex - (U32)(dictEnd - dictBase) : - 0; - const U32 dictHBitsL = dictMode == ZSTD_dictMatchState ? - dictCParams->hashLog : hBitsL; - const U32 dictHBitsS = dictMode == ZSTD_dictMatchState ? - dictCParams->chainLog : hBitsS; + const ZSTD_compressionParameters* const dictCParams = &dms->cParams; + const U32* const dictHashLong = dms->hashTable; + const U32* const dictHashSmall = dms->chainTable; + const U32 dictStartIndex = dms->window.dictLimit; + const BYTE* const dictBase = dms->window.base; + const BYTE* const dictStart = dictBase + dictStartIndex; + const BYTE* const dictEnd = dms->window.nextSrc; + const U32 dictIndexDelta = prefixLowestIndex - (U32)(dictEnd - dictBase); + const U32 dictHBitsL = dictCParams->hashLog; + const U32 dictHBitsS = dictCParams->chainLog; const U32 dictAndPrefixLength = (U32)((ip - prefixLowest) + (dictEnd - dictStart)); - DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_generic"); - - assert(dictMode == ZSTD_noDict || dictMode == ZSTD_dictMatchState); + DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_dictMatchState_generic"); /* if a dictionary is attached, it must be within window range */ - if (dictMode == ZSTD_dictMatchState) { - assert(ms->window.dictLimit + (1U << cParams->windowLog) >= endIndex); - } + assert(ms->window.dictLimit + (1U << cParams->windowLog) >= endIndex); /* init */ ip += (dictAndPrefixLength == 0); - if (dictMode == ZSTD_noDict) { - U32 const curr = (U32)(ip - base); - U32 const windowLow = ZSTD_getLowestPrefixIndex(ms, curr, cParams->windowLog); - U32 const maxRep = curr - windowLow; - if (offset_2 > maxRep) offsetSaved = offset_2, offset_2 = 0; - if (offset_1 > maxRep) offsetSaved = offset_1, offset_1 = 0; - } - if (dictMode == ZSTD_dictMatchState) { - /* dictMatchState repCode checks don't currently handle repCode == 0 - * disabling. */ - assert(offset_1 <= dictAndPrefixLength); - assert(offset_2 <= dictAndPrefixLength); - } + + /* dictMatchState repCode checks don't currently handle repCode == 0 + * disabling. */ + assert(offset_1 <= dictAndPrefixLength); + assert(offset_2 <= dictAndPrefixLength); /* Main Search Loop */ while (ip < ilimit) { /* < instead of <=, because repcode check at (ip+1) */ @@ -341,15 +317,13 @@ size_t ZSTD_compressBlock_doubleFast_generic( const BYTE* matchLong = base + matchIndexL; const BYTE* match = base + matchIndexS; const U32 repIndex = curr + 1 - offset_1; - const BYTE* repMatch = (dictMode == ZSTD_dictMatchState - && repIndex < prefixLowestIndex) ? + const BYTE* repMatch = (repIndex < prefixLowestIndex) ? dictBase + (repIndex - dictIndexDelta) : base + repIndex; hashLong[h2] = hashSmall[h] = curr; /* update hash tables */ - /* check dictMatchState repcode */ - if (dictMode == ZSTD_dictMatchState - && ((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) + /* check repcode */ + if (((U32)((prefixLowestIndex-1) - repIndex) >= 3 /* intentional underflow */) && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) { const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend; mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4; @@ -358,15 +332,6 @@ size_t ZSTD_compressBlock_doubleFast_generic( goto _match_stored; } - /* check noDict repcode */ - if ( dictMode == ZSTD_noDict - && ((offset_1 > 0) & (MEM_read32(ip+1-offset_1) == MEM_read32(ip+1)))) { - mLength = ZSTD_count(ip+1+4, ip+1+4-offset_1, iend) + 4; - ip++; - ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, 0, mLength-MINMATCH); - goto _match_stored; - } - if (matchIndexL > prefixLowestIndex) { /* check prefix long match */ if (MEM_read64(matchLong) == MEM_read64(ip)) { @@ -375,7 +340,7 @@ size_t ZSTD_compressBlock_doubleFast_generic( while (((ip>anchor) & (matchLong>prefixLowest)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */ goto _match_found; } - } else if (dictMode == ZSTD_dictMatchState) { + } else { /* check dictMatchState long match */ U32 const dictMatchIndexL = dictHashLong[dictHL]; const BYTE* dictMatchL = dictBase + dictMatchIndexL; @@ -393,7 +358,7 @@ size_t ZSTD_compressBlock_doubleFast_generic( if (MEM_read32(match) == MEM_read32(ip)) { goto _search_next_long; } - } else if (dictMode == ZSTD_dictMatchState) { + } else { /* check dictMatchState short match */ U32 const dictMatchIndexS = dictHashSmall[dictHS]; match = dictBase + dictMatchIndexS; @@ -426,7 +391,7 @@ _search_next_long: while (((ip>anchor) & (matchL3>prefixLowest)) && (ip[-1] == matchL3[-1])) { ip--; matchL3--; mLength++; } /* catch up */ goto _match_found; } - } else if (dictMode == ZSTD_dictMatchState) { + } else { /* check dict long +1 match */ U32 const dictMatchIndexL3 = dictHashLong[dictHLNext]; const BYTE* dictMatchL3 = dictBase + dictMatchIndexL3; @@ -440,7 +405,7 @@ _search_next_long: } } } /* if no long +1 match, explore the short match we found */ - if (dictMode == ZSTD_dictMatchState && matchIndexS < prefixLowestIndex) { + if (matchIndexS < prefixLowestIndex) { mLength = ZSTD_count_2segments(ip+4, match+4, iend, dictEnd, prefixLowest) + 4; offset = (U32)(curr - matchIndexS); while (((ip>anchor) & (match>dictStart)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */ @@ -472,43 +437,27 @@ _match_stored: } /* check immediate repcode */ - 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 + repIndex2 - dictIndexDelta : - 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; - size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixLowest) + 4; - U32 tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */ - ZSTD_storeSeq(seqStore, 0, anchor, iend, 0, repLength2-MINMATCH); - hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = current2; - hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = current2; - ip += repLength2; - anchor = ip; - continue; - } - break; - } } - - if (dictMode == ZSTD_noDict) { - while ( (ip <= ilimit) - && ( (offset_2>0) - & (MEM_read32(ip) == MEM_read32(ip - offset_2)) )) { - /* store sequence */ - size_t const rLength = ZSTD_count(ip+4, ip+4-offset_2, iend) + 4; - U32 const tmpOff = offset_2; offset_2 = offset_1; offset_1 = tmpOff; /* swap offset_2 <=> offset_1 */ - hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = (U32)(ip-base); - hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = (U32)(ip-base); - ZSTD_storeSeq(seqStore, 0, anchor, iend, 0, rLength-MINMATCH); - ip += rLength; + while (ip <= ilimit) { + U32 const current2 = (U32)(ip-base); + U32 const repIndex2 = current2 - offset_2; + const BYTE* repMatch2 = repIndex2 < prefixLowestIndex ? + dictBase + repIndex2 - dictIndexDelta : + 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; + size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixLowest) + 4; + U32 tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */ + ZSTD_storeSeq(seqStore, 0, anchor, iend, 0, repLength2-MINMATCH); + hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = current2; + hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = current2; + ip += repLength2; anchor = ip; - continue; /* faster when present ... (?) */ - } } } + continue; + } + break; + } + } } /* while (ip < ilimit) */ /* save reps for next block */ @@ -549,13 +498,13 @@ size_t ZSTD_compressBlock_doubleFast_dictMatchState( { default: /* includes case 3 */ case 4 : - return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 4, ZSTD_dictMatchState); + return ZSTD_compressBlock_doubleFast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 4); case 5 : - return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 5, ZSTD_dictMatchState); + return ZSTD_compressBlock_doubleFast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 5); case 6 : - return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 6, ZSTD_dictMatchState); + return ZSTD_compressBlock_doubleFast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 6); case 7 : - return ZSTD_compressBlock_doubleFast_generic(ms, seqStore, rep, src, srcSize, 7, ZSTD_dictMatchState); + return ZSTD_compressBlock_doubleFast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 7); } }