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-rw-r--r--vendor/github.com/DataDog/zstd/zstd_fast.c470
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);
- }
-}