}
-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 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];
- U32 offsetSaved = 0;
-
- /* init */
- 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;
- }
-
- /* 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;
- mLength += 4;
- 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 = ((size_t)(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 = 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;
-
- 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;
- }
-
- /* 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 (size_t)(iend - anchor);
-}
-
-
/**
* If you squint hard enough (and ignore repcodes), the search operation at any
* given position is broken into 4 stages:
* 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 | ...4
- * N+1 | ... 3 4
- * N+2 | ... 2 3 4
- * N+3 | 1 2 3
- * N+4 | 1 2
- * N+5 | 1
+ * 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
*
* Pos | Time -->
* ----+-------------------
- * N | 1 2 3
- * N+1 | 1 2
- * N+2 | 1
+ * 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_pipelined(
+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 BYTE* nextStep;
const size_t kStepIncr = (1 << (kSearchStrength - 1));
- DEBUGLOG(5, "ZSTD_compressBlock_fast_generic_pipelined");
+ DEBUGLOG(5, "ZSTD_compressBlock_fast_generic");
ip0 += (ip0 == prefixStart);
{ U32 const curr = (U32)(ip0 - base);
U32 const windowLow = ZSTD_getLowestPrefixIndex(ms, curr, cParams->windowLog);
{
default: /* includes case 3 */
case 4 :
- return ZSTD_compressBlock_fast_generic_pipelined(ms, seqStore, rep, src, srcSize, 4);
+ return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 4);
case 5 :
- return ZSTD_compressBlock_fast_generic_pipelined(ms, seqStore, rep, src, srcSize, 5);
+ return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 5);
case 6 :
- return ZSTD_compressBlock_fast_generic_pipelined(ms, seqStore, rep, src, srcSize, 6);
+ return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 6);
case 7 :
- return ZSTD_compressBlock_fast_generic_pipelined(ms, seqStore, rep, src, srcSize, 7);
+ return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, 7);
}
}
/* switch to "regular" variant if extDict is invalidated due to maxDistance */
if (prefixStartIndex == dictStartIndex)
- return ZSTD_compressBlock_fast_generic_pipelined(ms, seqStore, rep, src, srcSize, mls);
+ return ZSTD_compressBlock_fast_generic(ms, seqStore, rep, src, srcSize, mls);
/* Search Loop */
while (ip < ilimit) { /* < instead of <=, because (ip+1) */
projects / thirdparty / zstd.git / commitdiff
