From 8993bee997ee481abf737af31b333beea53408ab Mon Sep 17 00:00:00 2001 From: Yann Collet Date: Mon, 28 Nov 2016 16:11:30 -0800 Subject: [PATCH] restored normal mode --- lib/decompress/zstd_decompress.c | 321 +++++++++++++++++++++++-------- 1 file changed, 238 insertions(+), 83 deletions(-) diff --git a/lib/decompress/zstd_decompress.c b/lib/decompress/zstd_decompress.c index ea5722e2a..d96dd7841 100644 --- a/lib/decompress/zstd_decompress.c +++ b/lib/decompress/zstd_decompress.c @@ -788,7 +788,7 @@ typedef struct { } seqState_t; -static seq_t ZSTD_decodeSequence(seqState_t* seqState) +static seq_t ZSTD_decodeSequenceLong(seqState_t* seqState) { seq_t seq; @@ -914,7 +914,7 @@ size_t ZSTD_execSequenceLast7(BYTE* op, FORCE_INLINE -size_t ZSTD_execSequence(BYTE* op, +size_t ZSTD_execSequenceLong(BYTE* op, BYTE* const oend, seq_t sequence, const BYTE** litPtr, const BYTE* const litLimit, const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd) @@ -997,6 +997,242 @@ size_t ZSTD_execSequence(BYTE* op, } +#define ZSTD_PREFETCH(ptr) __builtin_prefetch(ptr, 0, 0); +static size_t ZSTD_decompressSequencesLong( + ZSTD_DCtx* dctx, + void* dst, size_t maxDstSize, + const void* seqStart, size_t seqSize) +{ + const BYTE* ip = (const BYTE*)seqStart; + const BYTE* const iend = ip + seqSize; + BYTE* const ostart = (BYTE* const)dst; + BYTE* const oend = ostart + maxDstSize; + BYTE* op = ostart; + const BYTE* litPtr = dctx->litPtr; + const BYTE* const litEnd = litPtr + dctx->litSize; + const BYTE* const base = (const BYTE*) (dctx->base); + const BYTE* const vBase = (const BYTE*) (dctx->vBase); + const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd); + int nbSeq; + + /* Build Decoding Tables */ + { size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); + if (ZSTD_isError(seqHSize)) return seqHSize; + ip += seqHSize; + } + + /* Regen sequences */ + if (nbSeq) { +#define STORED_SEQS 8 +#define STOSEQ_MASK (STORED_SEQS-1) +#define ADVANCED_SEQS 5 + seq_t sequences[STORED_SEQS]; + int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS); + seqState_t seqState; + int seqNb; + dctx->fseEntropy = 1; + { U32 i; for (i=0; irep[i]; } + seqState.ptr = op; + CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend-ip), corruption_detected); + FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); + FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); + FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); + + /* prepare in advance */ + for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNbrep[i] = (U32)(seqState.prevOffset[i]); } + } + + /* last literal segment */ + { size_t const lastLLSize = litEnd - litPtr; + if (lastLLSize > (size_t)(oend-op)) return ERROR(dstSize_tooSmall); + memcpy(op, litPtr, lastLLSize); + op += lastLLSize; + } + + return op-ostart; +} + + +static seq_t ZSTD_decodeSequence(seqState_t* seqState) +{ + seq_t seq; + + U32 const llCode = FSE_peekSymbol(&seqState->stateLL); + U32 const mlCode = FSE_peekSymbol(&seqState->stateML); + U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ + + U32 const llBits = LL_bits[llCode]; + U32 const mlBits = ML_bits[mlCode]; + U32 const ofBits = ofCode; + U32 const totalBits = llBits+mlBits+ofBits; + + static const U32 LL_base[MaxLL+1] = { + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, + 16, 18, 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, + 0x2000, 0x4000, 0x8000, 0x10000 }; + + static const U32 ML_base[MaxML+1] = { + 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, + 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, + 35, 37, 39, 41, 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, + 0x1003, 0x2003, 0x4003, 0x8003, 0x10003 }; + + static const U32 OF_base[MaxOff+1] = { + 0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, + 0xFD, 0x1FD, 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, + 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, + 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD }; + + /* sequence */ + { size_t offset; + if (!ofCode) + offset = 0; + else { + offset = OF_base[ofCode] + BIT_readBits(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ + if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); + } + + if (ofCode <= 1) { + offset += (llCode==0); + if (offset) { + size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; + temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ + if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset = temp; + } else { + offset = seqState->prevOffset[0]; + } + } else { + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset; + } + seq.offset = offset; + } + + seq.matchLength = ML_base[mlCode] + ((mlCode>31) ? BIT_readBits(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ + if (MEM_32bits() && (mlBits+llBits>24)) BIT_reloadDStream(&seqState->DStream); + + seq.litLength = LL_base[llCode] + ((llCode>15) ? BIT_readBits(&seqState->DStream, llBits) : 0); /* <= 16 bits */ + if (MEM_32bits() || + (totalBits > 64 - 7 - (LLFSELog+MLFSELog+OffFSELog)) ) BIT_reloadDStream(&seqState->DStream); + + /* ANS state update */ + FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ + FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ + if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ + FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ + + return seq; +} + + +FORCE_INLINE +size_t ZSTD_execSequence(BYTE* op, + BYTE* const oend, seq_t sequence, + const BYTE** litPtr, const BYTE* const litLimit, + const BYTE* const base, const BYTE* const vBase, const BYTE* const dictEnd) +{ + BYTE* const oLitEnd = op + sequence.litLength; + size_t const sequenceLength = sequence.litLength + sequence.matchLength; + BYTE* const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ + BYTE* const oend_w = oend - WILDCOPY_OVERLENGTH; + const BYTE* const iLitEnd = *litPtr + sequence.litLength; + const BYTE* match = oLitEnd - sequence.offset; + + /* check */ + if (oMatchEnd>oend) return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ + if (iLitEnd > litLimit) return ERROR(corruption_detected); /* over-read beyond lit buffer */ + if (oLitEnd>oend_w) return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); + + /* copy Literals */ + ZSTD_copy8(op, *litPtr); + if (sequence.litLength > 8) + ZSTD_wildcopy(op+8, (*litPtr)+8, sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ + op = oLitEnd; + *litPtr = iLitEnd; /* update for next sequence */ + + /* copy Match */ + if (sequence.offset > (size_t)(oLitEnd - base)) { + /* offset beyond prefix */ + if (sequence.offset > (size_t)(oLitEnd - vBase)) return ERROR(corruption_detected); + match = dictEnd - (base-match); + if (match + sequence.matchLength <= dictEnd) { + memmove(oLitEnd, match, sequence.matchLength); + return sequenceLength; + } + /* span extDict & currentPrefixSegment */ + { size_t const length1 = dictEnd - match; + memmove(oLitEnd, match, length1); + op = oLitEnd + length1; + sequence.matchLength -= length1; + match = base; + if (op > oend_w) { + U32 i; + for (i = 0; i < sequence.matchLength; ++i) op[i] = match[i]; + return sequenceLength; + } + } } + /* Requirement: op <= oend_w */ + + /* match within prefix */ + if (sequence.offset < 8) { + /* close range match, overlap */ + static const U32 dec32table[] = { 0, 1, 2, 1, 4, 4, 4, 4 }; /* added */ + static const int dec64table[] = { 8, 8, 8, 7, 8, 9,10,11 }; /* substracted */ + int const sub2 = dec64table[sequence.offset]; + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += dec32table[sequence.offset]; + ZSTD_copy4(op+4, match); + match -= sub2; + } else { + ZSTD_copy8(op, match); + } + op += 8; match += 8; + + if (oMatchEnd > oend-(16-MINMATCH)) { + if (op < oend_w) { + ZSTD_wildcopy(op, match, oend_w - op); + match += oend_w - op; + op = oend_w; + } + while (op < oMatchEnd) *op++ = *match++; + } else { + ZSTD_wildcopy(op, match, sequence.matchLength-8); /* works even if matchLength < 8 */ + } + return sequenceLength; +} + + static size_t ZSTD_decompressSequences( ZSTD_DCtx* dctx, void* dst, size_t maxDstSize, @@ -1054,86 +1290,6 @@ static size_t ZSTD_decompressSequences( return op-ostart; } -#define ZSTD_PREFETCH(ptr) __builtin_prefetch(ptr, 0, 0); -static size_t ZSTD_decompressSequencesLong( - ZSTD_DCtx* dctx, - void* dst, size_t maxDstSize, - const void* seqStart, size_t seqSize) -{ - const BYTE* ip = (const BYTE*)seqStart; - const BYTE* const iend = ip + seqSize; - BYTE* const ostart = (BYTE* const)dst; - BYTE* const oend = ostart + maxDstSize; - BYTE* op = ostart; - const BYTE* litPtr = dctx->litPtr; - const BYTE* const litEnd = litPtr + dctx->litSize; - const BYTE* const base = (const BYTE*) (dctx->base); - const BYTE* const vBase = (const BYTE*) (dctx->vBase); - const BYTE* const dictEnd = (const BYTE*) (dctx->dictEnd); - int nbSeq; - - /* Build Decoding Tables */ - { size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); - if (ZSTD_isError(seqHSize)) return seqHSize; - ip += seqHSize; - } - - /* Regen sequences */ - if (nbSeq) { -#define STORED_SEQS 8 -#define STOSEQ_MASK (STORED_SEQS-1) -#define ADVANCED_SEQS 5 - seq_t sequences[STORED_SEQS]; - seqState_t seqState; - int seqNb; - dctx->fseEntropy = 1; - { U32 i; for (i=0; irep[i]; } - seqState.ptr = op; - CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend-ip), corruption_detected); - FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); - FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); - FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); - - /* prepare in advance */ - int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS); - for (seqNb=0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNbrep[i] = (U32)(seqState.prevOffset[i]); } - } - - /* last literal segment */ - { size_t const lastLLSize = litEnd - litPtr; - if (lastLLSize > (size_t)(oend-op)) return ERROR(dstSize_tooSmall); - memcpy(op, litPtr, lastLLSize); - op += lastLLSize; - } - - return op-ostart; -} - static void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst) { @@ -1145,7 +1301,6 @@ static void ZSTD_checkContinuity(ZSTD_DCtx* dctx, const void* dst) } } - static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx* dctx, void* dst, size_t dstCapacity, const void* src, size_t srcSize)