--- /dev/null
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * 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_double_fast.h"
+
+static void ZSTD_fillDoubleHashTableForCDict(ZSTD_matchState_t* ms,
+ void const* end, ZSTD_dictTableLoadMethod_e dtlm)
+{
+ const ZSTD_compressionParameters* const cParams = &ms->cParams;
+ U32* const hashLarge = ms->hashTable;
+ U32 const hBitsL = cParams->hashLog + ZSTD_SHORT_CACHE_TAG_BITS;
+ U32 const mls = cParams->minMatch;
+ U32* const hashSmall = ms->chainTable;
+ U32 const hBitsS = cParams->chainLog + ZSTD_SHORT_CACHE_TAG_BITS;
+ 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 tables.
+ * Insert the other positions into the large hash table if their entry
+ * is empty.
+ */
+ for (; ip + fastHashFillStep - 1 <= iend; ip += fastHashFillStep) {
+ U32 const curr = (U32)(ip - base);
+ U32 i;
+ for (i = 0; i < fastHashFillStep; ++i) {
+ size_t const smHashAndTag = ZSTD_hashPtr(ip + i, hBitsS, mls);
+ size_t const lgHashAndTag = ZSTD_hashPtr(ip + i, hBitsL, 8);
+ if (i == 0) {
+ ZSTD_writeTaggedIndex(hashSmall, smHashAndTag, curr + i);
+ }
+ if (i == 0 || hashLarge[lgHashAndTag >> ZSTD_SHORT_CACHE_TAG_BITS] == 0) {
+ ZSTD_writeTaggedIndex(hashLarge, lgHashAndTag, curr + i);
+ }
+ /* Only load extra positions for ZSTD_dtlm_full */
+ if (dtlm == ZSTD_dtlm_fast)
+ break;
+ } }
+}
+
+static void ZSTD_fillDoubleHashTableForCCtx(ZSTD_matchState_t* ms,
+ void const* end, ZSTD_dictTableLoadMethod_e dtlm)
+{
+ const ZSTD_compressionParameters* const cParams = &ms->cParams;
+ U32* const hashLarge = ms->hashTable;
+ U32 const hBitsL = cParams->hashLog;
+ U32 const mls = cParams->minMatch;
+ U32* const hashSmall = ms->chainTable;
+ U32 const hBitsS = cParams->chainLog;
+ 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 tables.
+ * Insert the other positions into the large hash table if their entry
+ * is empty.
+ */
+ for (; ip + fastHashFillStep - 1 <= iend; ip += fastHashFillStep) {
+ U32 const curr = (U32)(ip - base);
+ U32 i;
+ for (i = 0; i < fastHashFillStep; ++i) {
+ size_t const smHash = ZSTD_hashPtr(ip + i, hBitsS, mls);
+ size_t const lgHash = ZSTD_hashPtr(ip + i, hBitsL, 8);
+ if (i == 0)
+ hashSmall[smHash] = curr + i;
+ if (i == 0 || hashLarge[lgHash] == 0)
+ hashLarge[lgHash] = curr + i;
+ /* Only load extra positions for ZSTD_dtlm_full */
+ if (dtlm == ZSTD_dtlm_fast)
+ break;
+ } }
+}
+
+void ZSTD_fillDoubleHashTable(ZSTD_matchState_t* ms,
+ const void* const end,
+ ZSTD_dictTableLoadMethod_e dtlm,
+ ZSTD_tableFillPurpose_e tfp)
+{
+ if (tfp == ZSTD_tfp_forCDict) {
+ ZSTD_fillDoubleHashTableForCDict(ms, end, dtlm);
+ } else {
+ ZSTD_fillDoubleHashTableForCCtx(ms, end, dtlm);
+ }
+}
+
+
+FORCE_INLINE_TEMPLATE
+size_t ZSTD_compressBlock_doubleFast_noDict_generic(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize, U32 const mls /* template */)
+{
+ ZSTD_compressionParameters const* cParams = &ms->cParams;
+ U32* const hashLong = ms->hashTable;
+ const U32 hBitsL = cParams->hashLog;
+ U32* const hashSmall = ms->chainTable;
+ const U32 hBitsS = cParams->chainLog;
+ const BYTE* const base = ms->window.base;
+ const BYTE* const istart = (const BYTE*)src;
+ const BYTE* anchor = istart;
+ const U32 endIndex = (U32)((size_t)(istart - base) + srcSize);
+ /* presumes that, if there is a dictionary, it must be using Attach mode */
+ const U32 prefixLowestIndex = ZSTD_getLowestPrefixIndex(ms, endIndex, cParams->windowLog);
+ const BYTE* const prefixLowest = base + prefixLowestIndex;
+ const BYTE* const iend = istart + srcSize;
+ const BYTE* const ilimit = iend - HASH_READ_SIZE;
+ U32 offset_1=rep[0], offset_2=rep[1];
+ U32 offsetSaved1 = 0, offsetSaved2 = 0;
+
+ size_t mLength;
+ U32 offset;
+ U32 curr;
+
+ /* how many positions to search before increasing step size */
+ const size_t kStepIncr = 1 << kSearchStrength;
+ /* the position at which to increment the step size if no match is found */
+ const BYTE* nextStep;
+ size_t step; /* the current step size */
+
+ size_t hl0; /* the long hash at ip */
+ size_t hl1; /* the long hash at ip1 */
+
+ U32 idxl0; /* the long match index for ip */
+ U32 idxl1; /* the long match index for ip1 */
+
+ const BYTE* matchl0; /* the long match for ip */
+ const BYTE* matchs0; /* the short match for ip */
+ const BYTE* matchl1; /* the long match for ip1 */
+
+ const BYTE* ip = istart; /* the current position */
+ const BYTE* ip1; /* the next position */
+
+ DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_noDict_generic");
+
+ /* init */
+ ip += ((ip - prefixLowest) == 0);
+ {
+ U32 const current = (U32)(ip - base);
+ U32 const windowLow = ZSTD_getLowestPrefixIndex(ms, current, cParams->windowLog);
+ U32 const maxRep = current - windowLow;
+ if (offset_2 > maxRep) offsetSaved2 = offset_2, offset_2 = 0;
+ if (offset_1 > maxRep) offsetSaved1 = offset_1, offset_1 = 0;
+ }
+
+ /* Outer Loop: one iteration per match found and stored */
+ while (1) {
+ step = 1;
+ nextStep = ip + kStepIncr;
+ ip1 = ip + step;
+
+ if (ip1 > ilimit) {
+ goto _cleanup;
+ }
+
+ hl0 = ZSTD_hashPtr(ip, hBitsL, 8);
+ idxl0 = hashLong[hl0];
+ matchl0 = base + idxl0;
+
+ /* Inner Loop: one iteration per search / position */
+ do {
+ const size_t hs0 = ZSTD_hashPtr(ip, hBitsS, mls);
+ const U32 idxs0 = hashSmall[hs0];
+ curr = (U32)(ip-base);
+ matchs0 = base + idxs0;
+
+ hashLong[hl0] = hashSmall[hs0] = curr; /* update hash tables */
+
+ /* check noDict repcode */
+ if ((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, REPCODE1_TO_OFFBASE, mLength);
+ goto _match_stored;
+ }
+
+ hl1 = ZSTD_hashPtr(ip1, hBitsL, 8);
+
+ if (idxl0 > prefixLowestIndex) {
+ /* check prefix long match */
+ if (MEM_read64(matchl0) == MEM_read64(ip)) {
+ mLength = ZSTD_count(ip+8, matchl0+8, iend) + 8;
+ offset = (U32)(ip-matchl0);
+ while (((ip>anchor) & (matchl0>prefixLowest)) && (ip[-1] == matchl0[-1])) { ip--; matchl0--; mLength++; } /* catch up */
+ goto _match_found;
+ }
+ }
+
+ idxl1 = hashLong[hl1];
+ matchl1 = base + idxl1;
+
+ if (idxs0 > prefixLowestIndex) {
+ /* check prefix short match */
+ if (MEM_read32(matchs0) == MEM_read32(ip)) {
+ goto _search_next_long;
+ }
+ }
+
+ if (ip1 >= nextStep) {
+ PREFETCH_L1(ip1 + 64);
+ PREFETCH_L1(ip1 + 128);
+ step++;
+ nextStep += kStepIncr;
+ }
+ ip = ip1;
+ ip1 += step;
+
+ hl0 = hl1;
+ idxl0 = idxl1;
+ matchl0 = matchl1;
+ #if defined(__aarch64__)
+ PREFETCH_L1(ip+256);
+ #endif
+ } while (ip1 <= ilimit);
+
+_cleanup:
+ /* If offset_1 started invalid (offsetSaved1 != 0) and became valid (offset_1 != 0),
+ * rotate saved offsets. See comment in ZSTD_compressBlock_fast_noDict for more context. */
+ offsetSaved2 = ((offsetSaved1 != 0) && (offset_1 != 0)) ? offsetSaved1 : offsetSaved2;
+
+ /* save reps for next block */
+ rep[0] = offset_1 ? offset_1 : offsetSaved1;
+ rep[1] = offset_2 ? offset_2 : offsetSaved2;
+
+ /* Return the last literals size */
+ return (size_t)(iend - anchor);
+
+_search_next_long:
+
+ /* check prefix long +1 match */
+ if (idxl1 > prefixLowestIndex) {
+ if (MEM_read64(matchl1) == MEM_read64(ip1)) {
+ ip = ip1;
+ mLength = ZSTD_count(ip+8, matchl1+8, iend) + 8;
+ offset = (U32)(ip-matchl1);
+ while (((ip>anchor) & (matchl1>prefixLowest)) && (ip[-1] == matchl1[-1])) { ip--; matchl1--; mLength++; } /* catch up */
+ goto _match_found;
+ }
+ }
+
+ /* if no long +1 match, explore the short match we found */
+ mLength = ZSTD_count(ip+4, matchs0+4, iend) + 4;
+ offset = (U32)(ip - matchs0);
+ while (((ip>anchor) & (matchs0>prefixLowest)) && (ip[-1] == matchs0[-1])) { ip--; matchs0--; mLength++; } /* catch up */
+
+ /* fall-through */
+
+_match_found: /* requires ip, offset, mLength */
+ offset_2 = offset_1;
+ offset_1 = offset;
+
+ if (step < 4) {
+ /* It is unsafe to write this value back to the hashtable when ip1 is
+ * greater than or equal to the new ip we will have after we're done
+ * processing this match. Rather than perform that test directly
+ * (ip1 >= ip + mLength), which costs speed in practice, we do a simpler
+ * more predictable test. The minmatch even if we take a short match is
+ * 4 bytes, so as long as step, the distance between ip and ip1
+ * (initially) is less than 4, we know ip1 < new ip. */
+ hashLong[hl1] = (U32)(ip1 - base);
+ }
+
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, OFFSET_TO_OFFBASE(offset), mLength);
+
+_match_stored:
+ /* match found */
+ ip += mLength;
+ anchor = ip;
+
+ if (ip <= ilimit) {
+ /* Complementary insertion */
+ /* done after iLimit test, as candidates could be > iend-8 */
+ { U32 const indexToInsert = curr+2;
+ hashLong[ZSTD_hashPtr(base+indexToInsert, hBitsL, 8)] = indexToInsert;
+ hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base);
+ hashSmall[ZSTD_hashPtr(base+indexToInsert, hBitsS, mls)] = indexToInsert;
+ hashSmall[ZSTD_hashPtr(ip-1, hBitsS, mls)] = (U32)(ip-1-base);
+ }
+
+ /* check immediate repcode */
+ 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, REPCODE1_TO_OFFBASE, rLength);
+ ip += rLength;
+ anchor = ip;
+ continue; /* faster when present ... (?) */
+ }
+ }
+ }
+}
+
+
+FORCE_INLINE_TEMPLATE
+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_compressionParameters const* cParams = &ms->cParams;
+ U32* const hashLong = ms->hashTable;
+ const U32 hBitsL = cParams->hashLog;
+ U32* const hashSmall = ms->chainTable;
+ const U32 hBitsS = cParams->chainLog;
+ const BYTE* const base = ms->window.base;
+ const BYTE* const istart = (const BYTE*)src;
+ const BYTE* ip = istart;
+ const BYTE* anchor = istart;
+ const U32 endIndex = (U32)((size_t)(istart - base) + srcSize);
+ /* presumes that, if there is a dictionary, it must be using Attach mode */
+ const U32 prefixLowestIndex = ZSTD_getLowestPrefixIndex(ms, endIndex, cParams->windowLog);
+ const BYTE* const prefixLowest = base + prefixLowestIndex;
+ const BYTE* const iend = istart + srcSize;
+ const BYTE* const ilimit = iend - HASH_READ_SIZE;
+ U32 offset_1=rep[0], offset_2=rep[1];
+
+ const ZSTD_matchState_t* const dms = ms->dictMatchState;
+ 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 + ZSTD_SHORT_CACHE_TAG_BITS;
+ const U32 dictHBitsS = dictCParams->chainLog + ZSTD_SHORT_CACHE_TAG_BITS;
+ const U32 dictAndPrefixLength = (U32)((ip - prefixLowest) + (dictEnd - dictStart));
+
+ DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_dictMatchState_generic");
+
+ /* if a dictionary is attached, it must be within window range */
+ assert(ms->window.dictLimit + (1U << cParams->windowLog) >= endIndex);
+
+ if (ms->prefetchCDictTables) {
+ size_t const hashTableBytes = (((size_t)1) << dictCParams->hashLog) * sizeof(U32);
+ size_t const chainTableBytes = (((size_t)1) << dictCParams->chainLog) * sizeof(U32);
+ PREFETCH_AREA(dictHashLong, hashTableBytes)
+ PREFETCH_AREA(dictHashSmall, chainTableBytes)
+ }
+
+ /* 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;
+ U32 offset;
+ size_t const h2 = ZSTD_hashPtr(ip, hBitsL, 8);
+ size_t const h = ZSTD_hashPtr(ip, hBitsS, mls);
+ size_t const dictHashAndTagL = ZSTD_hashPtr(ip, dictHBitsL, 8);
+ size_t const dictHashAndTagS = ZSTD_hashPtr(ip, dictHBitsS, mls);
+ U32 const dictMatchIndexAndTagL = dictHashLong[dictHashAndTagL >> ZSTD_SHORT_CACHE_TAG_BITS];
+ U32 const dictMatchIndexAndTagS = dictHashSmall[dictHashAndTagS >> ZSTD_SHORT_CACHE_TAG_BITS];
+ int const dictTagsMatchL = ZSTD_comparePackedTags(dictMatchIndexAndTagL, dictHashAndTagL);
+ int const dictTagsMatchS = ZSTD_comparePackedTags(dictMatchIndexAndTagS, dictHashAndTagS);
+ U32 const curr = (U32)(ip-base);
+ U32 const matchIndexL = hashLong[h2];
+ U32 matchIndexS = hashSmall[h];
+ const BYTE* matchLong = base + matchIndexL;
+ const BYTE* match = base + matchIndexS;
+ const U32 repIndex = curr + 1 - offset_1;
+ const BYTE* repMatch = (repIndex < prefixLowestIndex) ?
+ dictBase + (repIndex - dictIndexDelta) :
+ base + repIndex;
+ hashLong[h2] = hashSmall[h] = curr; /* update hash tables */
+
+ /* 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;
+ ip++;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, REPCODE1_TO_OFFBASE, mLength);
+ goto _match_stored;
+ }
+
+ if (matchIndexL > prefixLowestIndex) {
+ /* check prefix long match */
+ if (MEM_read64(matchLong) == MEM_read64(ip)) {
+ mLength = ZSTD_count(ip+8, matchLong+8, iend) + 8;
+ offset = (U32)(ip-matchLong);
+ while (((ip>anchor) & (matchLong>prefixLowest)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */
+ goto _match_found;
+ }
+ } else if (dictTagsMatchL) {
+ /* check dictMatchState long match */
+ U32 const dictMatchIndexL = dictMatchIndexAndTagL >> ZSTD_SHORT_CACHE_TAG_BITS;
+ const BYTE* dictMatchL = dictBase + dictMatchIndexL;
+ assert(dictMatchL < dictEnd);
+
+ if (dictMatchL > dictStart && MEM_read64(dictMatchL) == MEM_read64(ip)) {
+ mLength = ZSTD_count_2segments(ip+8, dictMatchL+8, iend, dictEnd, prefixLowest) + 8;
+ offset = (U32)(curr - dictMatchIndexL - dictIndexDelta);
+ while (((ip>anchor) & (dictMatchL>dictStart)) && (ip[-1] == dictMatchL[-1])) { ip--; dictMatchL--; mLength++; } /* catch up */
+ goto _match_found;
+ } }
+
+ if (matchIndexS > prefixLowestIndex) {
+ /* check prefix short match */
+ if (MEM_read32(match) == MEM_read32(ip)) {
+ goto _search_next_long;
+ }
+ } else if (dictTagsMatchS) {
+ /* check dictMatchState short match */
+ U32 const dictMatchIndexS = dictMatchIndexAndTagS >> ZSTD_SHORT_CACHE_TAG_BITS;
+ match = dictBase + dictMatchIndexS;
+ matchIndexS = dictMatchIndexS + dictIndexDelta;
+
+ if (match > dictStart && MEM_read32(match) == MEM_read32(ip)) {
+ goto _search_next_long;
+ } }
+
+ ip += ((ip-anchor) >> kSearchStrength) + 1;
+#if defined(__aarch64__)
+ PREFETCH_L1(ip+256);
+#endif
+ continue;
+
+_search_next_long:
+ { size_t const hl3 = ZSTD_hashPtr(ip+1, hBitsL, 8);
+ size_t const dictHashAndTagL3 = ZSTD_hashPtr(ip+1, dictHBitsL, 8);
+ U32 const matchIndexL3 = hashLong[hl3];
+ U32 const dictMatchIndexAndTagL3 = dictHashLong[dictHashAndTagL3 >> ZSTD_SHORT_CACHE_TAG_BITS];
+ int const dictTagsMatchL3 = ZSTD_comparePackedTags(dictMatchIndexAndTagL3, dictHashAndTagL3);
+ const BYTE* matchL3 = base + matchIndexL3;
+ hashLong[hl3] = curr + 1;
+
+ /* check prefix long +1 match */
+ if (matchIndexL3 > prefixLowestIndex) {
+ if (MEM_read64(matchL3) == MEM_read64(ip+1)) {
+ mLength = ZSTD_count(ip+9, matchL3+8, iend) + 8;
+ ip++;
+ offset = (U32)(ip-matchL3);
+ while (((ip>anchor) & (matchL3>prefixLowest)) && (ip[-1] == matchL3[-1])) { ip--; matchL3--; mLength++; } /* catch up */
+ goto _match_found;
+ }
+ } else if (dictTagsMatchL3) {
+ /* check dict long +1 match */
+ U32 const dictMatchIndexL3 = dictMatchIndexAndTagL3 >> ZSTD_SHORT_CACHE_TAG_BITS;
+ const BYTE* dictMatchL3 = dictBase + dictMatchIndexL3;
+ assert(dictMatchL3 < dictEnd);
+ if (dictMatchL3 > dictStart && MEM_read64(dictMatchL3) == MEM_read64(ip+1)) {
+ mLength = ZSTD_count_2segments(ip+1+8, dictMatchL3+8, iend, dictEnd, prefixLowest) + 8;
+ ip++;
+ offset = (U32)(curr + 1 - dictMatchIndexL3 - dictIndexDelta);
+ while (((ip>anchor) & (dictMatchL3>dictStart)) && (ip[-1] == dictMatchL3[-1])) { ip--; dictMatchL3--; mLength++; } /* catch up */
+ goto _match_found;
+ } } }
+
+ /* if no long +1 match, explore the short match we found */
+ 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 */
+ } else {
+ mLength = ZSTD_count(ip+4, match+4, iend) + 4;
+ offset = (U32)(ip - match);
+ while (((ip>anchor) & (match>prefixLowest)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
+ }
+
+_match_found:
+ offset_2 = offset_1;
+ offset_1 = offset;
+
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, OFFSET_TO_OFFBASE(offset), mLength);
+
+_match_stored:
+ /* match found */
+ ip += mLength;
+ anchor = ip;
+
+ if (ip <= ilimit) {
+ /* Complementary insertion */
+ /* done after iLimit test, as candidates could be > iend-8 */
+ { U32 const indexToInsert = curr+2;
+ hashLong[ZSTD_hashPtr(base+indexToInsert, hBitsL, 8)] = indexToInsert;
+ hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base);
+ hashSmall[ZSTD_hashPtr(base+indexToInsert, hBitsS, mls)] = indexToInsert;
+ hashSmall[ZSTD_hashPtr(ip-1, hBitsS, mls)] = (U32)(ip-1-base);
+ }
+
+ /* check immediate repcode */
+ 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, REPCODE1_TO_OFFBASE, repLength2);
+ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = current2;
+ hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = current2;
+ ip += repLength2;
+ anchor = ip;
+ continue;
+ }
+ break;
+ }
+ }
+ } /* while (ip < ilimit) */
+
+ /* save reps for next block */
+ rep[0] = offset_1;
+ rep[1] = offset_2;
+
+ /* Return the last literals size */
+ return (size_t)(iend - anchor);
+}
+
+#define ZSTD_GEN_DFAST_FN(dictMode, mls) \
+ static size_t ZSTD_compressBlock_doubleFast_##dictMode##_##mls( \
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], \
+ void const* src, size_t srcSize) \
+ { \
+ return ZSTD_compressBlock_doubleFast_##dictMode##_generic(ms, seqStore, rep, src, srcSize, mls); \
+ }
+
+ZSTD_GEN_DFAST_FN(noDict, 4)
+ZSTD_GEN_DFAST_FN(noDict, 5)
+ZSTD_GEN_DFAST_FN(noDict, 6)
+ZSTD_GEN_DFAST_FN(noDict, 7)
+
+ZSTD_GEN_DFAST_FN(dictMatchState, 4)
+ZSTD_GEN_DFAST_FN(dictMatchState, 5)
+ZSTD_GEN_DFAST_FN(dictMatchState, 6)
+ZSTD_GEN_DFAST_FN(dictMatchState, 7)
+
+
+size_t ZSTD_compressBlock_doubleFast(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize)
+{
+ const U32 mls = ms->cParams.minMatch;
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_doubleFast_noDict_4(ms, seqStore, rep, src, srcSize);
+ case 5 :
+ return ZSTD_compressBlock_doubleFast_noDict_5(ms, seqStore, rep, src, srcSize);
+ case 6 :
+ return ZSTD_compressBlock_doubleFast_noDict_6(ms, seqStore, rep, src, srcSize);
+ case 7 :
+ return ZSTD_compressBlock_doubleFast_noDict_7(ms, seqStore, rep, src, srcSize);
+ }
+}
+
+
+size_t ZSTD_compressBlock_doubleFast_dictMatchState(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize)
+{
+ const U32 mls = ms->cParams.minMatch;
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_doubleFast_dictMatchState_4(ms, seqStore, rep, src, srcSize);
+ case 5 :
+ return ZSTD_compressBlock_doubleFast_dictMatchState_5(ms, seqStore, rep, src, srcSize);
+ case 6 :
+ return ZSTD_compressBlock_doubleFast_dictMatchState_6(ms, seqStore, rep, src, srcSize);
+ case 7 :
+ return ZSTD_compressBlock_doubleFast_dictMatchState_7(ms, seqStore, rep, src, srcSize);
+ }
+}
+
+
+static size_t ZSTD_compressBlock_doubleFast_extDict_generic(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize,
+ U32 const mls /* template */)
+{
+ ZSTD_compressionParameters const* cParams = &ms->cParams;
+ U32* const hashLong = ms->hashTable;
+ U32 const hBitsL = cParams->hashLog;
+ U32* const hashSmall = ms->chainTable;
+ U32 const hBitsS = cParams->chainLog;
+ const BYTE* const istart = (const BYTE*)src;
+ const BYTE* ip = istart;
+ const BYTE* anchor = istart;
+ const BYTE* const iend = istart + srcSize;
+ const BYTE* const ilimit = iend - 8;
+ const BYTE* const base = ms->window.base;
+ const U32 endIndex = (U32)((size_t)(istart - base) + srcSize);
+ const U32 lowLimit = ZSTD_getLowestMatchIndex(ms, endIndex, cParams->windowLog);
+ const U32 dictStartIndex = lowLimit;
+ const U32 dictLimit = ms->window.dictLimit;
+ const U32 prefixStartIndex = (dictLimit > lowLimit) ? dictLimit : lowLimit;
+ const BYTE* const prefixStart = base + prefixStartIndex;
+ const BYTE* const dictBase = ms->window.dictBase;
+ const BYTE* const dictStart = dictBase + dictStartIndex;
+ const BYTE* const dictEnd = dictBase + prefixStartIndex;
+ U32 offset_1=rep[0], offset_2=rep[1];
+
+ DEBUGLOG(5, "ZSTD_compressBlock_doubleFast_extDict_generic (srcSize=%zu)", srcSize);
+
+ /* if extDict is invalidated due to maxDistance, switch to "regular" variant */
+ if (prefixStartIndex == dictStartIndex)
+ return ZSTD_compressBlock_doubleFast(ms, seqStore, rep, src, srcSize);
+
+ /* Search Loop */
+ while (ip < ilimit) { /* < instead of <=, because (ip+1) */
+ const size_t hSmall = ZSTD_hashPtr(ip, hBitsS, mls);
+ const U32 matchIndex = hashSmall[hSmall];
+ const BYTE* const matchBase = matchIndex < prefixStartIndex ? dictBase : base;
+ const BYTE* match = matchBase + matchIndex;
+
+ const size_t hLong = ZSTD_hashPtr(ip, hBitsL, 8);
+ const U32 matchLongIndex = hashLong[hLong];
+ const BYTE* const matchLongBase = matchLongIndex < prefixStartIndex ? dictBase : base;
+ const BYTE* matchLong = matchLongBase + matchLongIndex;
+
+ const U32 curr = (U32)(ip-base);
+ const U32 repIndex = curr + 1 - offset_1; /* offset_1 expected <= curr +1 */
+ const BYTE* const repBase = repIndex < prefixStartIndex ? dictBase : base;
+ const BYTE* const repMatch = repBase + repIndex;
+ size_t mLength;
+ hashSmall[hSmall] = hashLong[hLong] = curr; /* update hash table */
+
+ if ((((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow : ensure repIndex doesn't overlap dict + prefix */
+ & (offset_1 <= curr+1 - dictStartIndex)) /* note: we are searching at curr+1 */
+ && (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, (size_t)(ip-anchor), anchor, iend, REPCODE1_TO_OFFBASE, mLength);
+ } else {
+ if ((matchLongIndex > dictStartIndex) && (MEM_read64(matchLong) == MEM_read64(ip))) {
+ const BYTE* const matchEnd = matchLongIndex < prefixStartIndex ? dictEnd : iend;
+ const BYTE* const lowMatchPtr = matchLongIndex < prefixStartIndex ? dictStart : prefixStart;
+ U32 offset;
+ mLength = ZSTD_count_2segments(ip+8, matchLong+8, iend, matchEnd, prefixStart) + 8;
+ offset = curr - matchLongIndex;
+ while (((ip>anchor) & (matchLong>lowMatchPtr)) && (ip[-1] == matchLong[-1])) { ip--; matchLong--; mLength++; } /* catch up */
+ offset_2 = offset_1;
+ offset_1 = offset;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, OFFSET_TO_OFFBASE(offset), mLength);
+
+ } else if ((matchIndex > dictStartIndex) && (MEM_read32(match) == MEM_read32(ip))) {
+ size_t const h3 = ZSTD_hashPtr(ip+1, hBitsL, 8);
+ U32 const matchIndex3 = hashLong[h3];
+ const BYTE* const match3Base = matchIndex3 < prefixStartIndex ? dictBase : base;
+ const BYTE* match3 = match3Base + matchIndex3;
+ U32 offset;
+ hashLong[h3] = curr + 1;
+ if ( (matchIndex3 > dictStartIndex) && (MEM_read64(match3) == MEM_read64(ip+1)) ) {
+ const BYTE* const matchEnd = matchIndex3 < prefixStartIndex ? dictEnd : iend;
+ const BYTE* const lowMatchPtr = matchIndex3 < prefixStartIndex ? dictStart : prefixStart;
+ mLength = ZSTD_count_2segments(ip+9, match3+8, iend, matchEnd, prefixStart) + 8;
+ ip++;
+ offset = curr+1 - matchIndex3;
+ while (((ip>anchor) & (match3>lowMatchPtr)) && (ip[-1] == match3[-1])) { ip--; match3--; mLength++; } /* catch up */
+ } else {
+ const BYTE* const matchEnd = matchIndex < prefixStartIndex ? dictEnd : iend;
+ const BYTE* const lowMatchPtr = matchIndex < prefixStartIndex ? dictStart : prefixStart;
+ mLength = ZSTD_count_2segments(ip+4, match+4, iend, matchEnd, prefixStart) + 4;
+ offset = curr - matchIndex;
+ while (((ip>anchor) & (match>lowMatchPtr)) && (ip[-1] == match[-1])) { ip--; match--; mLength++; } /* catch up */
+ }
+ offset_2 = offset_1;
+ offset_1 = offset;
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, OFFSET_TO_OFFBASE(offset), mLength);
+
+ } else {
+ ip += ((ip-anchor) >> kSearchStrength) + 1;
+ continue;
+ } }
+
+ /* move to next sequence start */
+ ip += mLength;
+ anchor = ip;
+
+ if (ip <= ilimit) {
+ /* Complementary insertion */
+ /* done after iLimit test, as candidates could be > iend-8 */
+ { U32 const indexToInsert = curr+2;
+ hashLong[ZSTD_hashPtr(base+indexToInsert, hBitsL, 8)] = indexToInsert;
+ hashLong[ZSTD_hashPtr(ip-2, hBitsL, 8)] = (U32)(ip-2-base);
+ hashSmall[ZSTD_hashPtr(base+indexToInsert, hBitsS, mls)] = indexToInsert;
+ hashSmall[ZSTD_hashPtr(ip-1, hBitsS, mls)] = (U32)(ip-1-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) /* intentional overflow : ensure repIndex2 doesn't overlap dict + prefix */
+ & (offset_2 <= current2 - dictStartIndex))
+ && (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 const tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; /* swap offset_2 <=> offset_1 */
+ ZSTD_storeSeq(seqStore, 0, anchor, iend, REPCODE1_TO_OFFBASE, repLength2);
+ hashSmall[ZSTD_hashPtr(ip, hBitsS, mls)] = current2;
+ hashLong[ZSTD_hashPtr(ip, hBitsL, 8)] = 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 (size_t)(iend - anchor);
+}
+
+ZSTD_GEN_DFAST_FN(extDict, 4)
+ZSTD_GEN_DFAST_FN(extDict, 5)
+ZSTD_GEN_DFAST_FN(extDict, 6)
+ZSTD_GEN_DFAST_FN(extDict, 7)
+
+size_t ZSTD_compressBlock_doubleFast_extDict(
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
+ void const* src, size_t srcSize)
+{
+ U32 const mls = ms->cParams.minMatch;
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_doubleFast_extDict_4(ms, seqStore, rep, src, srcSize);
+ case 5 :
+ return ZSTD_compressBlock_doubleFast_extDict_5(ms, seqStore, rep, src, srcSize);
+ case 6 :
+ return ZSTD_compressBlock_doubleFast_extDict_6(ms, seqStore, rep, src, srcSize);
+ case 7 :
+ return ZSTD_compressBlock_doubleFast_extDict_7(ms, seqStore, rep, src, srcSize);
+ }
+}
notaz.gp2x.de / pcsx_rearmed.git / blobdiff