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-rw-r--r--lib/zstd/compress/zstd_fast.c441
1 files changed, 310 insertions, 131 deletions
diff --git a/lib/zstd/compress/zstd_fast.c b/lib/zstd/compress/zstd_fast.c
index 96b7d48e2868..a752e6beab52 100644
--- a/lib/zstd/compress/zstd_fast.c
+++ b/lib/zstd/compress/zstd_fast.c
@@ -43,145 +43,294 @@ void ZSTD_fillHashTable(ZSTD_matchState_t* ms,
}
+/*
+ * If you squint hard enough (and ignore repcodes), the search operation at any
+ * given position is broken into 4 stages:
+ *
+ * 1. Hash (map position to hash value via input read)
+ * 2. Lookup (map hash val to index via hashtable read)
+ * 3. Load (map index to value at that position via input read)
+ * 4. Compare
+ *
+ * Each of these steps involves a memory read at an address which is computed
+ * from the previous step. This means these steps must be sequenced and their
+ * latencies are cumulative.
+ *
+ * Rather than do 1->2->3->4 sequentially for a single position before moving
+ * onto the next, this implementation interleaves these operations across the
+ * next few positions:
+ *
+ * R = Repcode Read & Compare
+ * H = Hash
+ * T = Table Lookup
+ * M = Match Read & Compare
+ *
+ * Pos | Time -->
+ * ----+-------------------
+ * N | ... M
+ * N+1 | ... TM
+ * N+2 | R H T M
+ * N+3 | H TM
+ * N+4 | R H T M
+ * N+5 | H ...
+ * N+6 | R ...
+ *
+ * This is very much analogous to the pipelining of execution in a CPU. And just
+ * like a CPU, we have to dump the pipeline when we find a match (i.e., take a
+ * branch).
+ *
+ * When this happens, we throw away our current state, and do the following prep
+ * to re-enter the loop:
+ *
+ * Pos | Time -->
+ * ----+-------------------
+ * N | H T
+ * N+1 | H
+ *
+ * This is also the work we do at the beginning to enter the loop initially.
+ */
FORCE_INLINE_TEMPLATE size_t
-ZSTD_compressBlock_fast_generic(
+ZSTD_compressBlock_fast_noDict_generic(
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
void const* src, size_t srcSize,
- U32 const mls)
+ U32 const mls, U32 const hasStep)
{
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;
+ size_t const stepSize = hasStep ? (cParams->targetLength + !(cParams->targetLength) + 1) : 2;
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 endIndex = (U32)((size_t)(istart - base) + srcSize);
const U32 prefixStartIndex = ZSTD_getLowestPrefixIndex(ms, endIndex, cParams->windowLog);
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];
+
+ const BYTE* anchor = istart;
+ const BYTE* ip0 = istart;
+ const BYTE* ip1;
+ const BYTE* ip2;
+ const BYTE* ip3;
+ U32 current0;
+
+ U32 rep_offset1 = rep[0];
+ U32 rep_offset2 = rep[1];
U32 offsetSaved = 0;
- /* init */
+ size_t hash0; /* hash for ip0 */
+ size_t hash1; /* hash for ip1 */
+ U32 idx; /* match idx for ip0 */
+ U32 mval; /* src value at match idx */
+
+ U32 offcode;
+ const BYTE* match0;
+ size_t mLength;
+
+ /* ip0 and ip1 are always adjacent. The targetLength skipping and
+ * uncompressibility acceleration is applied to every other position,
+ * matching the behavior of #1562. step therefore represents the gap
+ * between pairs of positions, from ip0 to ip2 or ip1 to ip3. */
+ size_t step;
+ const BYTE* nextStep;
+ const size_t kStepIncr = (1 << (kSearchStrength - 1));
+
DEBUGLOG(5, "ZSTD_compressBlock_fast_generic");
ip0 += (ip0 == prefixStart);
- ip1 = ip0 + 1;
{ U32 const curr = (U32)(ip0 - 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 (rep_offset2 > maxRep) offsetSaved = rep_offset2, rep_offset2 = 0;
+ if (rep_offset1 > maxRep) offsetSaved = rep_offset1, rep_offset1 = 0;
}
- /* Main Search Loop */
-#ifdef __INTEL_COMPILER
- /* From intel 'The vector pragma indicates that the loop should be
- * vectorized if it is legal to do so'. Can be used together with
- * #pragma ivdep (but have opted to exclude that because intel
- * warns against using it).*/
- #pragma vector always
-#endif
- 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;
-
-#if defined(__aarch64__)
- PREFETCH_L1(ip0+256);
-#endif
-
- 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;
+ /* start each op */
+_start: /* Requires: ip0 */
+
+ step = stepSize;
+ nextStep = ip0 + kStepIncr;
+
+ /* calculate positions, ip0 - anchor == 0, so we skip step calc */
+ ip1 = ip0 + 1;
+ ip2 = ip0 + step;
+ ip3 = ip2 + 1;
+
+ if (ip3 >= ilimit) {
+ goto _cleanup;
+ }
+
+ hash0 = ZSTD_hashPtr(ip0, hlog, mls);
+ hash1 = ZSTD_hashPtr(ip1, hlog, mls);
+
+ idx = hashTable[hash0];
+
+ do {
+ /* load repcode match for ip[2]*/
+ const U32 rval = MEM_read32(ip2 - rep_offset1);
+
+ /* write back hash table entry */
+ current0 = (U32)(ip0 - base);
+ hashTable[hash0] = current0;
+
+ /* check repcode at ip[2] */
+ if ((MEM_read32(ip2) == rval) & (rep_offset1 > 0)) {
+ ip0 = ip2;
+ match0 = ip0 - rep_offset1;
+ mLength = ip0[-1] == match0[-1];
+ ip0 -= mLength;
+ match0 -= mLength;
+ offcode = STORE_REPCODE_1;
mLength += 4;
- offcode = 0;
goto _match;
}
- if ((matchIndex0 > prefixStartIndex) && MEM_read32(match0) == val0) {
- /* found a regular match */
- goto _offset;
+
+ /* load match for ip[0] */
+ if (idx >= prefixStartIndex) {
+ mval = MEM_read32(base + idx);
+ } else {
+ mval = MEM_read32(ip0) ^ 1; /* guaranteed to not match. */
}
- if ((matchIndex1 > prefixStartIndex) && MEM_read32(match1) == val1) {
- /* found a regular match after one literal */
- ip0 = ip1;
- match0 = match1;
+
+ /* check match at ip[0] */
+ if (MEM_read32(ip0) == mval) {
+ /* found a match! */
goto _offset;
}
- { size_t const step = ((size_t)(ip0-anchor) >> (kSearchStrength - 1)) + stepSize;
- assert(step >= 2);
- ip0 += step;
- ip1 += step;
- continue;
+
+ /* lookup ip[1] */
+ idx = hashTable[hash1];
+
+ /* hash ip[2] */
+ hash0 = hash1;
+ hash1 = ZSTD_hashPtr(ip2, hlog, mls);
+
+ /* advance to next positions */
+ ip0 = ip1;
+ ip1 = ip2;
+ ip2 = ip3;
+
+ /* write back hash table entry */
+ current0 = (U32)(ip0 - base);
+ hashTable[hash0] = current0;
+
+ /* load match for ip[0] */
+ if (idx >= prefixStartIndex) {
+ mval = MEM_read32(base + idx);
+ } else {
+ mval = MEM_read32(ip0) ^ 1; /* guaranteed to not match. */
}
-_offset: /* Requires: ip0, match0 */
- /* Compute the offset code */
- offset_2 = offset_1;
- offset_1 = (U32)(ip0-match0);
- offcode = offset_1 + ZSTD_REP_MOVE;
- mLength = 4;
- /* 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, match0+mLength, iend);
- ZSTD_storeSeq(seqStore, (size_t)(ip0-anchor), anchor, iend, offcode, mLength-MINMATCH);
- /* match found */
- ip0 += mLength;
- anchor = ip0;
+ /* check match at ip[0] */
+ if (MEM_read32(ip0) == mval) {
+ /* found a match! */
+ goto _offset;
+ }
- 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);
-
- if (offset_2 > 0) { /* offset_2==0 means offset_2 is invalidated */
- while ( (ip0 <= ilimit) && (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;
- ZSTD_storeSeq(seqStore, 0 /*litLen*/, anchor, iend, 0 /*offCode*/, rLength-MINMATCH);
- anchor = ip0;
- continue; /* faster when present (confirmed on gcc-8) ... (?) */
- } } }
- ip1 = ip0 + 1;
- }
+ /* lookup ip[1] */
+ idx = hashTable[hash1];
+
+ /* hash ip[2] */
+ hash0 = hash1;
+ hash1 = ZSTD_hashPtr(ip2, hlog, mls);
+
+ /* advance to next positions */
+ ip0 = ip1;
+ ip1 = ip2;
+ ip2 = ip0 + step;
+ ip3 = ip1 + step;
+
+ /* calculate step */
+ if (ip2 >= nextStep) {
+ step++;
+ PREFETCH_L1(ip1 + 64);
+ PREFETCH_L1(ip1 + 128);
+ nextStep += kStepIncr;
+ }
+ } while (ip3 < ilimit);
+
+_cleanup:
+ /* Note that there are probably still a couple positions we could search.
+ * However, it seems to be a meaningful performance hit to try to search
+ * them. So let's not. */
/* save reps for next block */
- rep[0] = offset_1 ? offset_1 : offsetSaved;
- rep[1] = offset_2 ? offset_2 : offsetSaved;
+ rep[0] = rep_offset1 ? rep_offset1 : offsetSaved;
+ rep[1] = rep_offset2 ? rep_offset2 : offsetSaved;
/* Return the last literals size */
return (size_t)(iend - anchor);
+
+_offset: /* Requires: ip0, idx */
+
+ /* Compute the offset code. */
+ match0 = base + idx;
+ rep_offset2 = rep_offset1;
+ rep_offset1 = (U32)(ip0-match0);
+ offcode = STORE_OFFSET(rep_offset1);
+ mLength = 4;
+
+ /* Count the backwards match length. */
+ while (((ip0>anchor) & (match0>prefixStart)) && (ip0[-1] == match0[-1])) {
+ ip0--;
+ match0--;
+ mLength++;
+ }
+
+_match: /* Requires: ip0, match0, offcode */
+
+ /* Count the forward length. */
+ mLength += ZSTD_count(ip0 + mLength, match0 + mLength, iend);
+
+ ZSTD_storeSeq(seqStore, (size_t)(ip0 - anchor), anchor, iend, offcode, mLength);
+
+ ip0 += mLength;
+ anchor = ip0;
+
+ /* write next hash table entry */
+ if (ip1 < ip0) {
+ hashTable[hash1] = (U32)(ip1 - base);
+ }
+
+ /* Fill table and check for immediate repcode. */
+ 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);
+
+ if (rep_offset2 > 0) { /* rep_offset2==0 means rep_offset2 is invalidated */
+ while ( (ip0 <= ilimit) && (MEM_read32(ip0) == MEM_read32(ip0 - rep_offset2)) ) {
+ /* store sequence */
+ size_t const rLength = ZSTD_count(ip0+4, ip0+4-rep_offset2, iend) + 4;
+ { U32 const tmpOff = rep_offset2; rep_offset2 = rep_offset1; rep_offset1 = tmpOff; } /* swap rep_offset2 <=> rep_offset1 */
+ hashTable[ZSTD_hashPtr(ip0, hlog, mls)] = (U32)(ip0-base);
+ ip0 += rLength;
+ ZSTD_storeSeq(seqStore, 0 /*litLen*/, anchor, iend, STORE_REPCODE_1, rLength);
+ anchor = ip0;
+ continue; /* faster when present (confirmed on gcc-8) ... (?) */
+ } } }
+
+ goto _start;
}
+#define ZSTD_GEN_FAST_FN(dictMode, mls, step) \
+ static size_t ZSTD_compressBlock_fast_##dictMode##_##mls##_##step( \
+ ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM], \
+ void const* src, size_t srcSize) \
+ { \
+ return ZSTD_compressBlock_fast_##dictMode##_generic(ms, seqStore, rep, src, srcSize, mls, step); \
+ }
+
+ZSTD_GEN_FAST_FN(noDict, 4, 1)
+ZSTD_GEN_FAST_FN(noDict, 5, 1)
+ZSTD_GEN_FAST_FN(noDict, 6, 1)
+ZSTD_GEN_FAST_FN(noDict, 7, 1)
+
+ZSTD_GEN_FAST_FN(noDict, 4, 0)
+ZSTD_GEN_FAST_FN(noDict, 5, 0)
+ZSTD_GEN_FAST_FN(noDict, 6, 0)
+ZSTD_GEN_FAST_FN(noDict, 7, 0)
size_t ZSTD_compressBlock_fast(
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
@@ -189,24 +338,40 @@ size_t ZSTD_compressBlock_fast(
{
U32 const mls = ms->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);
+ if (ms->cParams.targetLength > 1) {
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_fast_noDict_4_1(ms, seqStore, rep, src, srcSize);
+ case 5 :
+ return ZSTD_compressBlock_fast_noDict_5_1(ms, seqStore, rep, src, srcSize);
+ case 6 :
+ return ZSTD_compressBlock_fast_noDict_6_1(ms, seqStore, rep, src, srcSize);
+ case 7 :
+ return ZSTD_compressBlock_fast_noDict_7_1(ms, seqStore, rep, src, srcSize);
+ }
+ } else {
+ switch(mls)
+ {
+ default: /* includes case 3 */
+ case 4 :
+ return ZSTD_compressBlock_fast_noDict_4_0(ms, seqStore, rep, src, srcSize);
+ case 5 :
+ return ZSTD_compressBlock_fast_noDict_5_0(ms, seqStore, rep, src, srcSize);
+ case 6 :
+ return ZSTD_compressBlock_fast_noDict_6_0(ms, seqStore, rep, src, srcSize);
+ case 7 :
+ return ZSTD_compressBlock_fast_noDict_7_0(ms, seqStore, rep, src, srcSize);
+ }
+
}
}
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)
+ void const* src, size_t srcSize, U32 const mls, U32 const hasStep)
{
const ZSTD_compressionParameters* const cParams = &ms->cParams;
U32* const hashTable = ms->hashTable;
@@ -242,6 +407,8 @@ size_t ZSTD_compressBlock_fast_dictMatchState_generic(
assert(endIndex - prefixStartIndex <= maxDistance);
(void)maxDistance; (void)endIndex; /* these variables are not used when assert() is disabled */
+ (void)hasStep; /* not currently specialized on whether it's accelerated */
+
/* ensure there will be no underflow
* when translating a dict index into a local index */
assert(prefixStartIndex >= (U32)(dictEnd - dictBase));
@@ -272,7 +439,7 @@ size_t ZSTD_compressBlock_fast_dictMatchState_generic(
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, (size_t)(ip-anchor), anchor, iend, 0, mLength-MINMATCH);
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, STORE_REPCODE_1, mLength);
} else if ( (matchIndex <= prefixStartIndex) ) {
size_t const dictHash = ZSTD_hashPtr(ip, dictHLog, mls);
U32 const dictMatchIndex = dictHashTable[dictHash];
@@ -292,7 +459,7 @@ size_t ZSTD_compressBlock_fast_dictMatchState_generic(
} /* catch up */
offset_2 = offset_1;
offset_1 = offset;
- ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, STORE_OFFSET(offset), mLength);
}
} else if (MEM_read32(match) != MEM_read32(ip)) {
/* it's not a match, and we're not going to check the dictionary */
@@ -307,7 +474,7 @@ size_t ZSTD_compressBlock_fast_dictMatchState_generic(
&& (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 + ZSTD_REP_MOVE, mLength-MINMATCH);
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, STORE_OFFSET(offset), mLength);
}
/* match found */
@@ -332,7 +499,7 @@ size_t ZSTD_compressBlock_fast_dictMatchState_generic(
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, iend, 0, repLength2-MINMATCH);
+ ZSTD_storeSeq(seqStore, 0, anchor, iend, STORE_REPCODE_1, repLength2);
hashTable[ZSTD_hashPtr(ip, hlog, mls)] = current2;
ip += repLength2;
anchor = ip;
@@ -351,6 +518,12 @@ size_t ZSTD_compressBlock_fast_dictMatchState_generic(
return (size_t)(iend - anchor);
}
+
+ZSTD_GEN_FAST_FN(dictMatchState, 4, 0)
+ZSTD_GEN_FAST_FN(dictMatchState, 5, 0)
+ZSTD_GEN_FAST_FN(dictMatchState, 6, 0)
+ZSTD_GEN_FAST_FN(dictMatchState, 7, 0)
+
size_t ZSTD_compressBlock_fast_dictMatchState(
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
void const* src, size_t srcSize)
@@ -361,20 +534,20 @@ size_t ZSTD_compressBlock_fast_dictMatchState(
{
default: /* includes case 3 */
case 4 :
- return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 4);
+ return ZSTD_compressBlock_fast_dictMatchState_4_0(ms, seqStore, rep, src, srcSize);
case 5 :
- return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 5);
+ return ZSTD_compressBlock_fast_dictMatchState_5_0(ms, seqStore, rep, src, srcSize);
case 6 :
- return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 6);
+ return ZSTD_compressBlock_fast_dictMatchState_6_0(ms, seqStore, rep, src, srcSize);
case 7 :
- return ZSTD_compressBlock_fast_dictMatchState_generic(ms, seqStore, rep, src, srcSize, 7);
+ return ZSTD_compressBlock_fast_dictMatchState_7_0(ms, seqStore, rep, src, srcSize);
}
}
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)
+ void const* src, size_t srcSize, U32 const mls, U32 const hasStep)
{
const ZSTD_compressionParameters* const cParams = &ms->cParams;
U32* const hashTable = ms->hashTable;
@@ -398,11 +571,13 @@ static size_t ZSTD_compressBlock_fast_extDict_generic(
const BYTE* const ilimit = iend - 8;
U32 offset_1=rep[0], offset_2=rep[1];
+ (void)hasStep; /* not currently specialized on whether it's accelerated */
+
DEBUGLOG(5, "ZSTD_compressBlock_fast_extDict_generic (offset_1=%u)", offset_1);
/* switch to "regular" variant if extDict is invalidated due to maxDistance */
if (prefixStartIndex == dictStartIndex)
- return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, mls);
+ return ZSTD_compressBlock_fast(ms, seqStore, rep, src, srcSize);
/* Search Loop */
while (ip < ilimit) { /* < instead of <=, because (ip+1) */
@@ -416,14 +591,14 @@ static size_t ZSTD_compressBlock_fast_extDict_generic(
const BYTE* const repMatch = repBase + repIndex;
hashTable[h] = curr; /* update hash table */
DEBUGLOG(7, "offset_1 = %u , curr = %u", offset_1, curr);
- assert(offset_1 <= curr +1); /* check repIndex */
- if ( (((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow */ & (repIndex > dictStartIndex))
+ if ( ( ((U32)((prefixStartIndex-1) - repIndex) >= 3) /* intentional underflow */
+ & (offset_1 <= curr+1 - dictStartIndex) ) /* note: we are searching at curr+1 */
&& (MEM_read32(repMatch) == MEM_read32(ip+1)) ) {
const BYTE* const repMatchEnd = repIndex < prefixStartIndex ? dictEnd : iend;
size_t const rLength = ZSTD_count_2segments(ip+1 +4, repMatch +4, iend, repMatchEnd, prefixStart) + 4;
ip++;
- ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, 0, rLength-MINMATCH);
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, STORE_REPCODE_1, rLength);
ip += rLength;
anchor = ip;
} else {
@@ -439,7 +614,7 @@ static size_t ZSTD_compressBlock_fast_extDict_generic(
size_t 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_2 = offset_1; offset_1 = offset; /* update offset history */
- ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, offset + ZSTD_REP_MOVE, mLength-MINMATCH);
+ ZSTD_storeSeq(seqStore, (size_t)(ip-anchor), anchor, iend, STORE_OFFSET(offset), mLength);
ip += mLength;
anchor = ip;
} }
@@ -453,12 +628,12 @@ static size_t ZSTD_compressBlock_fast_extDict_generic(
U32 const current2 = (U32)(ip-base);
U32 const repIndex2 = current2 - offset_2;
const BYTE* const repMatch2 = repIndex2 < prefixStartIndex ? dictBase + repIndex2 : base + repIndex2;
- if ( (((U32)((prefixStartIndex-1) - repIndex2) >= 3) & (repIndex2 > dictStartIndex)) /* intentional overflow */
+ if ( (((U32)((prefixStartIndex-1) - repIndex2) >= 3) & (offset_2 <= curr - 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 const tmpOffset = offset_2; offset_2 = offset_1; offset_1 = tmpOffset; } /* swap offset_2 <=> offset_1 */
- ZSTD_storeSeq(seqStore, 0 /*litlen*/, anchor, iend, 0 /*offcode*/, repLength2-MINMATCH);
+ ZSTD_storeSeq(seqStore, 0 /*litlen*/, anchor, iend, STORE_REPCODE_1, repLength2);
hashTable[ZSTD_hashPtr(ip, hlog, mls)] = current2;
ip += repLength2;
anchor = ip;
@@ -475,6 +650,10 @@ static size_t ZSTD_compressBlock_fast_extDict_generic(
return (size_t)(iend - anchor);
}
+ZSTD_GEN_FAST_FN(extDict, 4, 0)
+ZSTD_GEN_FAST_FN(extDict, 5, 0)
+ZSTD_GEN_FAST_FN(extDict, 6, 0)
+ZSTD_GEN_FAST_FN(extDict, 7, 0)
size_t ZSTD_compressBlock_fast_extDict(
ZSTD_matchState_t* ms, seqStore_t* seqStore, U32 rep[ZSTD_REP_NUM],
@@ -485,12 +664,12 @@ size_t ZSTD_compressBlock_fast_extDict(
{
default: /* includes case 3 */
case 4 :
- return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 4);
+ return ZSTD_compressBlock_fast_extDict_4_0(ms, seqStore, rep, src, srcSize);
case 5 :
- return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 5);
+ return ZSTD_compressBlock_fast_extDict_5_0(ms, seqStore, rep, src, srcSize);
case 6 :
- return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 6);
+ return ZSTD_compressBlock_fast_extDict_6_0(ms, seqStore, rep, src, srcSize);
case 7 :
- return ZSTD_compressBlock_fast_extDict_generic(ms, seqStore, rep, src, srcSize, 7);
+ return ZSTD_compressBlock_fast_extDict_7_0(ms, seqStore, rep, src, srcSize);
}
}