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abstracted storeSeq() sumtype numeric representation from zstd_lazy.c

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This commit is contained in:
Yann Collet 2021-12-28 12:23:39 -08:00
parent e909fa627f
commit 92a08eec72
1 changed files with 44 additions and 44 deletions
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88
lib/compress/zstd_lazy.c
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@ -1539,7 +1539,7 @@ ZSTD_compressBlock_lazy_generic(
#endif
while (ip < ilimit) {
size_t matchLength=0;
size_t offset=0;
size_t offcode=0;
const BYTE* start=ip+1;
/* check repCode */
@ -1566,7 +1566,7 @@ ZSTD_compressBlock_lazy_generic(
{ size_t offsetFound = 999999999;
size_t const ml2 = searchMax(ms, ip, iend, &offsetFound);
if (ml2 > matchLength)
matchLength = ml2, start = ip, offset=offsetFound;
matchLength = ml2, start = ip, offcode=offsetFound;
}
if (matchLength < 4) {
@ -1579,12 +1579,12 @@ ZSTD_compressBlock_lazy_generic(
while (ip<ilimit) {
ip ++;
if ( (dictMode == ZSTD_noDict)
&& (offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) {
&& (offcode) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) {
size_t const mlRep = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4;
int const gain2 = (int)(mlRep * 3);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 1);
if ((mlRep >= 4) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
matchLength = mlRep, offcode = 0, start = ip;
}
if (isDxS) {
const U32 repIndex = (U32)(ip - base) - offset_1;
@ -1596,17 +1596,17 @@ ZSTD_compressBlock_lazy_generic(
const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend;
size_t const mlRep = ZSTD_count_2segments(ip+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4;
int const gain2 = (int)(mlRep * 3);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 1);
if ((mlRep >= 4) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
matchLength = mlRep, offcode = 0, start = ip;
}
}
{ size_t offset2=999999999;
size_t const ml2 = searchMax(ms, ip, iend, &offset2);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 4);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 4);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
matchLength = ml2, offcode = offset2, start = ip;
continue; /* search a better one */
} }
@ -1614,12 +1614,12 @@ ZSTD_compressBlock_lazy_generic(
if ((depth==2) && (ip<ilimit)) {
ip ++;
if ( (dictMode == ZSTD_noDict)
&& (offset) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) {
&& (offcode) && ((offset_1>0) & (MEM_read32(ip) == MEM_read32(ip - offset_1)))) {
size_t const mlRep = ZSTD_count(ip+4, ip+4-offset_1, iend) + 4;
int const gain2 = (int)(mlRep * 4);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 1);
if ((mlRep >= 4) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
matchLength = mlRep, offcode = 0, start = ip;
}
if (isDxS) {
const U32 repIndex = (U32)(ip - base) - offset_1;
@ -1631,17 +1631,17 @@ ZSTD_compressBlock_lazy_generic(
const BYTE* repMatchEnd = repIndex < prefixLowestIndex ? dictEnd : iend;
size_t const mlRep = ZSTD_count_2segments(ip+4, repMatch+4, iend, repMatchEnd, prefixLowest) + 4;
int const gain2 = (int)(mlRep * 4);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 1);
if ((mlRep >= 4) && (gain2 > gain1))
matchLength = mlRep, offset = 0, start = ip;
matchLength = mlRep, offcode = 0, start = ip;
}
}
{ size_t offset2=999999999;
size_t const ml2 = searchMax(ms, ip, iend, &offset2);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 7);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offset2))); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 7);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
matchLength = ml2, offcode = offset2, start = ip;
continue;
} } }
break; /* nothing found : store previous solution */
@ -1653,24 +1653,24 @@ ZSTD_compressBlock_lazy_generic(
* overflows the pointer, which is undefined behavior.
*/
/* catch up */
if (offset) {
if (offcode) {
if (dictMode == ZSTD_noDict) {
while ( ((start > anchor) & (start - STORED_OFFSET(offset) > prefixLowest))
&& (start[-1] == (start-STORED_OFFSET(offset))[-1]) ) /* only search for offset within prefix */
while ( ((start > anchor) & (start - STORED_OFFSET(offcode) > prefixLowest))
&& (start[-1] == (start-STORED_OFFSET(offcode))[-1]) ) /* only search for offset within prefix */
{ start--; matchLength++; }
}
if (isDxS) {
U32 const matchIndex = (U32)((size_t)(start-base) - STORED_OFFSET(offset));
U32 const matchIndex = (U32)((size_t)(start-base) - STORED_OFFSET(offcode));
const BYTE* match = (matchIndex < prefixLowestIndex) ? dictBase + matchIndex - dictIndexDelta : base + matchIndex;
const BYTE* const mStart = (matchIndex < prefixLowestIndex) ? dictLowest : prefixLowest;
while ((start>anchor) && (match>mStart) && (start[-1] == match[-1])) { start--; match--; matchLength++; } /* catch up */
}
offset_2 = offset_1; offset_1 = (U32)STORED_OFFSET(offset);
offset_2 = offset_1; offset_1 = (U32)STORED_OFFSET(offcode);
}
/* store sequence */
_storeSequence:
{ size_t const litLength = (size_t)(start - anchor);
ZSTD_storeSeq(seqStore, litLength, anchor, iend, (U32)offset, matchLength);
ZSTD_storeSeq(seqStore, litLength, anchor, iend, (U32)offcode, matchLength);
anchor = ip = start + matchLength;
}
@ -1686,7 +1686,7 @@ _storeSequence:
&& (MEM_read32(repMatch) == MEM_read32(ip)) ) {
const BYTE* const repEnd2 = repIndex < prefixLowestIndex ? dictEnd : iend;
matchLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd2, prefixLowest) + 4;
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap offset_2 <=> offset_1 */
offcode = offset_2; offset_2 = offset_1; offset_1 = (U32)offcode; /* swap offset_2 <=> offset_1 */
ZSTD_storeSeq(seqStore, 0, anchor, iend, STORE_REPCODE_1, matchLength);
ip += matchLength;
anchor = ip;
@ -1701,7 +1701,7 @@ _storeSequence:
&& (MEM_read32(ip) == MEM_read32(ip - offset_2)) ) {
/* store sequence */
matchLength = ZSTD_count(ip+4, ip+4-offset_2, iend) + 4;
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap repcodes */
offcode = offset_2; offset_2 = offset_1; offset_1 = (U32)offcode; /* swap repcodes */
ZSTD_storeSeq(seqStore, 0, anchor, iend, STORE_REPCODE_1, matchLength);
ip += matchLength;
anchor = ip;
@ -1903,7 +1903,7 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
#endif
while (ip < ilimit) {
size_t matchLength=0;
size_t offset=0;
size_t offcode=0;
const BYTE* start=ip+1;
U32 curr = (U32)(ip-base);
@ -1925,7 +1925,7 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
{ size_t offsetFound = 999999999;
size_t const ml2 = searchMax(ms, ip, iend, &offsetFound);
if (ml2 > matchLength)
matchLength = ml2, start = ip, offset=offsetFound;
matchLength = ml2, start = ip, offcode=offsetFound;
}
if (matchLength < 4) {
@ -1939,7 +1939,7 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
ip ++;
curr++;
/* check repCode */
if (offset) {
if (offcode) {
const U32 windowLow = ZSTD_getLowestMatchIndex(ms, curr, windowLog);
const U32 repIndex = (U32)(curr - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
@ -1951,18 +1951,18 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
size_t const repLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4;
int const gain2 = (int)(repLength * 3);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32((U32)offset+1) + 1);
int const gain1 = (int)(matchLength*3 - ZSTD_highbit32(STORED_TO_OFFBASE(offcode)) + 1);
if ((repLength >= 4) && (gain2 > gain1))
matchLength = repLength, offset = 0, start = ip;
matchLength = repLength, offcode = 0, start = ip;
} }
/* search match, depth 1 */
{ size_t offset2=999999999;
size_t const ml2 = searchMax(ms, ip, iend, &offset2);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 4);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32(STORED_TO_OFFBASE(offset2))); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32(STORED_TO_OFFBASE(offcode)) + 4);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
matchLength = ml2, offcode = offset2, start = ip;
continue; /* search a better one */
} }
@ -1971,7 +1971,7 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
ip ++;
curr++;
/* check repCode */
if (offset) {
if (offcode) {
const U32 windowLow = ZSTD_getLowestMatchIndex(ms, curr, windowLog);
const U32 repIndex = (U32)(curr - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
@ -1983,36 +1983,36 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
size_t const repLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4;
int const gain2 = (int)(repLength * 4);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 1);
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 1);
if ((repLength >= 4) && (gain2 > gain1))
matchLength = repLength, offset = 0, start = ip;
matchLength = repLength, offcode = 0, start = ip;
} }
/* search match, depth 2 */
{ size_t offset2=999999999;
size_t const ml2 = searchMax(ms, ip, iend, &offset2);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)offset2+1)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offset+1) + 7);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offset2))); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)STORED_TO_OFFBASE(offcode)) + 7);
if ((ml2 >= 4) && (gain2 > gain1)) {
matchLength = ml2, offset = offset2, start = ip;
matchLength = ml2, offcode = offset2, start = ip;
continue;
} } }
break; /* nothing found : store previous solution */
}
/* catch up */
if (offset) {
U32 const matchIndex = (U32)((size_t)(start-base) - STORED_OFFSET(offset));
if (offcode) {
U32 const matchIndex = (U32)((size_t)(start-base) - STORED_OFFSET(offcode));
const BYTE* match = (matchIndex < dictLimit) ? dictBase + matchIndex : base + matchIndex;
const BYTE* const mStart = (matchIndex < dictLimit) ? dictStart : prefixStart;
while ((start>anchor) && (match>mStart) && (start[-1] == match[-1])) { start--; match--; matchLength++; } /* catch up */
offset_2 = offset_1; offset_1 = (U32)STORED_OFFSET(offset);
offset_2 = offset_1; offset_1 = (U32)STORED_OFFSET(offcode);
}
/* store sequence */
_storeSequence:
{ size_t const litLength = (size_t)(start - anchor);
ZSTD_storeSeq(seqStore, litLength, anchor, iend, (U32)offset, matchLength);
ZSTD_storeSeq(seqStore, litLength, anchor, iend, (U32)offcode, matchLength);
anchor = ip = start + matchLength;
}
@ -2029,7 +2029,7 @@ _storeSequence:
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
matchLength = ZSTD_count_2segments(ip+4, repMatch+4, iend, repEnd, prefixStart) + 4;
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap offset history */
offcode = offset_2; offset_2 = offset_1; offset_1 = (U32)offcode; /* swap offset history */
ZSTD_storeSeq(seqStore, 0, anchor, iend, STORE_REPCODE_1, matchLength);
ip += matchLength;
anchor = ip;