diff options
Diffstat (limited to 'vendor/github.com/DataDog/zstd/zstd_fast.c')
| -rw-r--r-- | vendor/github.com/DataDog/zstd/zstd_fast.c | 470 |
1 files changed, 0 insertions, 470 deletions
diff --git a/vendor/github.com/DataDog/zstd/zstd_fast.c b/vendor/github.com/DataDog/zstd/zstd_fast.c deleted file mode 100644 index ed997b441..000000000 --- a/vendor/github.com/DataDog/zstd/zstd_fast.c +++ /dev/null @@ -1,470 +0,0 @@ -/* - * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. - * All rights reserved. - * - * This source code is licensed under both the BSD-style license (found in the - * LICENSE file in the root directory of this source tree) and the GPLv2 (found - * in the COPYING file in the root directory of this source tree). - * You may select, at your option, one of the above-listed licenses. - */ - -#include "zstd_compress_internal.h" -#include "zstd_fast.h" - - -void ZSTD_fillHashTable(ZSTD_matchState_t* ms, - void const* end, ZSTD_dictTableLoadMethod_e dtlm) -{ - const ZSTD_compressionParameters* const cParams = &ms->cParams; - U32* const hashTable = ms->hashTable; - U32 const hBits = cParams->hashLog; - U32 const mls = cParams->minMatch; - const BYTE* const base = ms->window.base; - const BYTE* ip = base + ms->nextToUpdate; - const BYTE* const iend = ((const BYTE*)end) - HASH_READ_SIZE; - const U32 fastHashFillStep = 3; - - /* Always insert every fastHashFillStep position into the hash table. - * Insert the other positions if their hash entry is empty. - */ - for ( ; ip + fastHashFillStep < iend + 2; ip += fastHashFillStep) { - U32 const current = (U32)(ip - base); - size_t const hash0 = ZSTD_hashPtr(ip, hBits, mls); - hashTable[hash0] = current; - if (dtlm == ZSTD_dtlm_fast) continue; - /* Only load extra positions for ZSTD_dtlm_full */ - { U32 p; - for (p = 1; p < fastHashFillStep; ++p) { - size_t const hash = ZSTD_hashPtr(ip + p, hBits, mls); - if (hashTable[hash] == 0) { /* not yet filled */ - hashTable[hash] = current + p; - } } } } -} - -FORCE_INLINE_TEMPLATE -size_t ZSTD_compressBlock_fast_generic( - ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], - void const* src, size_t srcSize, - U32 const mls) -{ - const ZSTD_compressionParameters* const cParams = &ms->cParams; - U32* const hashTable = ms->hashTable; - U32 const hlog = cParams->hashLog; - /* support stepSize of 0 */ - size_t const stepSize = cParams->targetLength + !(cParams->targetLength) + 1; - const BYTE* const base = ms->window.base; - const BYTE* const istart = (const BYTE*)src; - /* We check ip0 (ip + 0) and ip1 (ip + 1) each loop */ - const BYTE* ip0 = istart; - const BYTE* ip1; - const BYTE* anchor = istart; - const U32 prefixStartIndex = ms->window.dictLimit; - const BYTE* const prefixStart = base + prefixStartIndex; - const BYTE* const iend = istart + srcSize; - const BYTE* const ilimit = iend - HASH_READ_SIZE; - U32 offset_1=rep[0], offset_2=rep[1]; - U32 offsetSaved = 0; - - /* init */ - ip0 += (ip0 == prefixStart); - ip1 = ip0 + 1; - { - U32 const maxRep = (U32)(ip0 - prefixStart); - if (offset_2 > maxRep) offsetSaved = offset_2, offset_2 = 0; - if (offset_1 > maxRep) offsetSaved = offset_1, offset_1 = 0; - } - - /* Main Search Loop */ - while (ip1 < ilimit) { /* < instead of <=, because check at ip0+2 */ - size_t mLength; - BYTE const* ip2 = ip0 + 2; - size_t const h0 = ZSTD_hashPtr(ip0, hlog, mls); - U32 const val0 = MEM_read32(ip0); - size_t const h1 = ZSTD_hashPtr(ip1, hlog, mls); - U32 const val1 = MEM_read32(ip1); - U32 const current0 = (U32)(ip0-base); - U32 const current1 = (U32)(ip1-base); - U32 const matchIndex0 = hashTable[h0]; - U32 const matchIndex1 = hashTable[h1]; - BYTE const* repMatch = ip2-offset_1; - const BYTE* match0 = base + matchIndex0; - const BYTE* match1 = base + matchIndex1; - U32 offcode; - hashTable[h0] = current0; /* update hash table */ - hashTable[h1] = current1; /* update hash table */ - - assert(ip0 + 1 == ip1); - - if ((offset_1 > 0) & (MEM_read32(repMatch) == MEM_read32(ip2))) { - mLength = ip2[-1] == repMatch[-1] ? 1 : 0; - ip0 = ip2 - mLength; - match0 = repMatch - mLength; - offcode = 0; - goto _match; - } - if ((matchIndex0 > prefixStartIndex) && MEM_read32(match0) == val0) { - /* found a regular match */ - goto _offset; - } - if ((matchIndex1 > prefixStartIndex) && MEM_read32(match1) == val1) { - /* found a regular match after one literal */ - ip0 = ip1; - match0 = match1; - goto _offset; - } - { - size_t const step = ((ip0-anchor) >> (kSearchStrength - 1)) + stepSize; - assert(step >= 2); - ip0 += step; - ip1 += step; - continue; - } -_offset: /* Requires: ip0, match0 */ - /* Compute the offset code */ - offset_2 = offset_1; - offset_1 = (U32)(ip0-match0); - offcode = offset_1 + ZSTD_REP_MOVE; - mLength = 0; - /* Count the backwards match length */ - while (((ip0>anchor) & (match0>prefixStart)) - && (ip0[-1] == match0[-1])) { ip0--; match0--; mLength++; } /* catch up */ - -_match: /* Requires: ip0, match0, offcode */ - /* Count the forward length */ - mLength += ZSTD_count(ip0+mLength+4, match0+mLength+4, iend) + 4; - ZSTD_storeSeq(seqStore, ip0-anchor, anchor, offcode, mLength-MINMATCH); - /* match found */ - ip0 += mLength; - anchor = ip0; - ip1 = ip0 + 1; - - if (ip0 <= ilimit) { - /* Fill Table */ - assert(base+current0+2 > istart); /* check base overflow */ - hashTable[ZSTD_hashPtr(base+current0+2, hlog, mls)] = current0+2; /* here because current+2 could be > iend-8 */ - hashTable[ZSTD_hashPtr(ip0-2, hlog, mls)] = (U32)(ip0-2-base); - - while ( (ip0 <= ilimit) - && ( (offset_2>0) - & (MEM_read32(ip0) == MEM_read32(ip0 - offset_2)) )) { - /* store sequence */ - size_t const rLength = ZSTD_count(ip0+4, ip0+4-offset_2, iend) + 4; - U32 const tmpOff = offset_2; offset_2 = offset_1; offset_1 = tmpOff; /* swap offset_2 <=> offset_1 */ - hashTable[ZSTD_hashPtr(ip0, hlog, mls)] = (U32)(ip0-base); - ip0 += rLength; - ip1 = ip0 + 1; - ZSTD_storeSeq(seqStore, 0, anchor, 0, rLength-MINMATCH); - anchor = ip0; - continue; /* faster when present (confirmed on gcc-8) ... (?) */ - } - } - } - - /* save reps for next block */ - rep[0] = offset_1 ? offset_1 : offsetSaved; - rep[1] = offset_2 ? offset_2 : offsetSaved; - - /* Return the last literals size */ - return iend - anchor; -} - - -size_t ZSTD_compressBlock_fast( - ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], - void const* src, size_t srcSize) -{ - ZSTD_compressionParameters const* cParams = &ms->cParams; - U32 const mls = cParams->minMatch; - assert(ms->dictMatchState == NULL); - switch(mls) - { - default: /* includes case 3 */ - case 4 : - return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 4); - case 5 : - return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 5); - case 6 : - return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 6); - case 7 : - return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 7); - } -} - -FORCE_INLINE_TEMPLATE -size_t ZSTD_compressBlock_fast_dictMatchState_generic( - ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], - void const* src, size_t srcSize, U32 const mls) -{ - const ZSTD_compressionParameters* const cParams = &ms->cParams; - U32* const hashTable = ms->hashTable; - U32 const hlog = cParams->hashLog; - /* support stepSize of 0 */ - U32 const stepSize = cParams->targetLength + !(cParams->targetLength); - const BYTE* const base = ms->window.base; - const BYTE* const istart = (const BYTE*)src; - const BYTE* ip = istart; - const BYTE* anchor = istart; - const U32 prefixStartIndex = ms->window.dictLimit; - const BYTE* const prefixStart = base + prefixStartIndex; - const BYTE* const iend = istart + srcSize; - const BYTE* const ilimit = iend - HASH_READ_SIZE; - U32 offset_1=rep[0], offset_2=rep[1]; - U32 offsetSaved = 0; - - const ZSTD_matchState_t* const dms = ms->dictMatchState; - const ZSTD_compressionParameters* const dictCParams = &dms->cParams ; - const U32* const dictHashTable = dms->hashTable; - 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 = prefixStartIndex - (U32)(dictEnd - dictBase); - const U32 dictAndPrefixLength = (U32)(ip - prefixStart + dictEnd - dictStart); - const U32 dictHLog = dictCParams->hashLog; - - /* otherwise, we would get index underflow when translating a dict index - * into a local index */ - assert(prefixStartIndex >= (U32)(dictEnd - dictBase)); - - /* init */ - ip += (dictAndPrefixLength == 0); - /* 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) */ - size_t mLength; - size_t const h = ZSTD_hashPtr(ip, hlog, mls); - U32 const current = (U32)(ip-base); - U32 const matchIndex = hashTable[h]; - const BYTE* match = base + matchIndex; - const U32 repIndex = current + 1 - offset_1; - const BYTE* repMatch = (repIndex < prefixStartIndex) ? - dictBase + (repIndex - dictIndexDelta) : - base + repIndex; - hashTable[h] = current; /* update hash table */ - - if ( ((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow : ensure repIndex isn't overlapping dict + prefix */ - && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) { - const BYTE* const repMatchEnd = repIndex < prefixStartIndex ? dictEnd : iend; - mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixStart) + 4; - ip++; - ZSTD_storeSeq(seqStore, ip-anchor, anchor, 0, mLength-MINMATCH); - } else if ( (matchIndex <= prefixStartIndex) ) { - size_t const dictHash = ZSTD_hashPtr(ip, dictHLog, mls); - U32 const dictMatchIndex = dictHashTable[dictHash]; - const BYTE* dictMatch = dictBase + dictMatchIndex; - if (dictMatchIndex <= dictStartIndex || - MEM_read32(dictMatch) != MEM_read32(ip)) { - assert(stepSize >= 1); - ip += ((ip-anchor) >> kSearchStrength) + stepSize; - continue; - } else { - /* found a dict match */ - U32 const offset = (U32)(current-dictMatchIndex-dictIndexDelta); - mLength = ZSTD_count_2segments(ip+4, dictMatch+4, iend, dictEnd, prefixStart) + 4; - while (((ip>anchor) & (dictMatch>dictStart)) - && (ip[-1] == dictMatch[-1])) { - ip--; dictMatch--; mLength++; - } /* catch up */ - offset_2 = offset_1; - offset_1 = offset; - ZSTD_storeSeq(seqStore, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH); - } - } else if (MEM_read32(match) != MEM_read32(ip)) { - /* it's not a match, and we're not going to check the dictionary */ - assert(stepSize >= 1); - ip += ((ip-anchor) >> kSearchStrength) + stepSize; - continue; - } else { - /* found a regular match */ - U32 const offset = (U32)(ip-match); - mLength = ZSTD_count(ip+4, match+4, iend) + 4; - while (((ip>anchor) & (match>prefixStart)) - && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */ - offset_2 = offset_1; - offset_1 = offset; - ZSTD_storeSeq(seqStore, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH); - } - - /* match found */ - ip += mLength; - anchor = ip; - - if (ip <= ilimit) { - /* Fill Table */ - assert(base+current+2 > istart); /* check base overflow */ - hashTable[ZSTD_hashPtr(base+current+2, hlog, mls)] = current+2; /* here because current+2 could be > iend-8 */ - hashTable[ZSTD_hashPtr(ip-2, hlog, mls)] = (U32)(ip-2-base); - - /* check immediate repcode */ - while (ip <= ilimit) { - U32 const current2 = (U32)(ip-base); - U32 const repIndex2 = current2 - offset_2; - const BYTE* repMatch2 = repIndex2 < prefixStartIndex ? - dictBase - dictIndexDelta + repIndex2 : - base + repIndex2; - if ( ((U32)((prefixStartIndex-1) - (U32)repIndex2) >= 3 /* intentional overflow */) - && (MEM_read32(repMatch2) == MEM_read32(ip)) ) { - const BYTE* const repEnd2 = repIndex2 < prefixStartIndex ? dictEnd : iend; - size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixStart) + 4; - U32 tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */ - ZSTD_storeSeq(seqStore, 0, anchor, 0, repLength2-MINMATCH); - hashTable[ZSTD_hashPtr(ip, hlog, mls)] = current2; - ip += repLength2; - anchor = ip; - continue; - } - break; - } - } - } - - /* save reps for next block */ - rep[0] = offset_1 ? offset_1 : offsetSaved; - rep[1] = offset_2 ? offset_2 : offsetSaved; - - /* Return the last literals size */ - return iend - anchor; -} - -size_t ZSTD_compressBlock_fast_dictMatchState( - ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], - void const* src, size_t srcSize) -{ - ZSTD_compressionParameters const* cParams = &ms->cParams; - U32 const mls = cParams->minMatch; - assert(ms->dictMatchState != NULL); - switch(mls) - { - default: /* includes case 3 */ - case 4 : - return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 4); - case 5 : - return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 5); - case 6 : - return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 6); - case 7 : - return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 7); - } -} - - -static size_t ZSTD_compressBlock_fast_extDict_generic( - ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], - void const* src, size_t srcSize, U32 const mls) -{ - const ZSTD_compressionParameters* const cParams = &ms->cParams; - U32* const hashTable = ms->hashTable; - U32 const hlog = cParams->hashLog; - /* support stepSize of 0 */ - U32 const stepSize = cParams->targetLength + !(cParams->targetLength); - const BYTE* const base = ms->window.base; - const BYTE* const dictBase = ms->window.dictBase; - const BYTE* const istart = (const BYTE*)src; - const BYTE* ip = istart; - const BYTE* anchor = istart; - const U32 dictStartIndex = ms->window.lowLimit; - const BYTE* const dictStart = dictBase + dictStartIndex; - const U32 prefixStartIndex = ms->window.dictLimit; - const BYTE* const prefixStart = base + prefixStartIndex; - const BYTE* const dictEnd = dictBase + prefixStartIndex; - const BYTE* const iend = istart + srcSize; - const BYTE* const ilimit = iend - 8; - U32 offset_1=rep[0], offset_2=rep[1]; - - /* Search Loop */ - while (ip < ilimit) { /* < instead of <=, because (ip+1) */ - const size_t h = ZSTD_hashPtr(ip, hlog, mls); - const U32 matchIndex = hashTable[h]; - const BYTE* const matchBase = matchIndex < prefixStartIndex ? dictBase : base; - const BYTE* match = matchBase + matchIndex; - const U32 current = (U32)(ip-base); - const U32 repIndex = current + 1 - offset_1; - const BYTE* const repBase = repIndex < prefixStartIndex ? dictBase : base; - const BYTE* const repMatch = repBase + repIndex; - size_t mLength; - hashTable[h] = current; /* update hash table */ - assert(offset_1 <= current +1); /* check repIndex */ - - if ( (((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > dictStartIndex)) - && (MEM_read32(repMatch) == MEM_read32(ip+1)) ) { - const BYTE* repMatchEnd = repIndex < prefixStartIndex ? dictEnd : iend; - mLength = ZSTD_count_2segments(ip+1+4, repMatch+4, iend, repMatchEnd, prefixStart) + 4; - ip++; - ZSTD_storeSeq(seqStore, ip-anchor, anchor, 0, mLength-MINMATCH); - } else { - if ( (matchIndex < dictStartIndex) || - (MEM_read32(match) != MEM_read32(ip)) ) { - assert(stepSize >= 1); - ip += ((ip-anchor) >> kSearchStrength) + stepSize; - continue; - } - { const BYTE* matchEnd = matchIndex < prefixStartIndex ? dictEnd : iend; - const BYTE* lowMatchPtr = matchIndex < prefixStartIndex ? dictStart : prefixStart; - U32 offset; - mLength = ZSTD_count_2segments(ip+4, match+4, iend, matchEnd, prefixStart) + 4; - while (((ip>anchor) & (match>lowMatchPtr)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */ - offset = current - matchIndex; - offset_2 = offset_1; - offset_1 = offset; - ZSTD_storeSeq(seqStore, ip-anchor, anchor, offset + ZSTD_REP_MOVE, mLength-MINMATCH); - } } - - /* found a match : store it */ - ip += mLength; - anchor = ip; - - if (ip <= ilimit) { - /* Fill Table */ - hashTable[ZSTD_hashPtr(base+current+2, hlog, mls)] = current+2; - hashTable[ZSTD_hashPtr(ip-2, hlog, mls)] = (U32)(ip-2-base); - /* check immediate repcode */ - while (ip <= ilimit) { - U32 const current2 = (U32)(ip-base); - U32 const repIndex2 = current2 - offset_2; - const BYTE* repMatch2 = repIndex2 < prefixStartIndex ? dictBase + repIndex2 : base + repIndex2; - if ( (((U32)((prefixStartIndex-1) - repIndex2) >= 3) & (repIndex2 > dictStartIndex)) /* intentional overflow */ - && (MEM_read32(repMatch2) == MEM_read32(ip)) ) { - const BYTE* const repEnd2 = repIndex2 < prefixStartIndex ? dictEnd : iend; - size_t const repLength2 = ZSTD_count_2segments(ip+4, repMatch2+4, iend, repEnd2, prefixStart) + 4; - U32 tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */ - ZSTD_storeSeq(seqStore, 0, anchor, 0, repLength2-MINMATCH); - hashTable[ZSTD_hashPtr(ip, hlog, mls)] = current2; - ip += repLength2; - anchor = ip; - continue; - } - break; - } } } - - /* save reps for next block */ - rep[0] = offset_1; - rep[1] = offset_2; - - /* Return the last literals size */ - return iend - anchor; -} - - -size_t ZSTD_compressBlock_fast_extDict( - ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], - void const* src, size_t srcSize) -{ - ZSTD_compressionParameters const* cParams = &ms->cParams; - U32 const mls = cParams->minMatch; - switch(mls) - { - default: /* includes case 3 */ - case 4 : - return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 4); - case 5 : - return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 5); - case 6 : - return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 6); - case 7 : - return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 7); - } -} |