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fixed minor compression difference in btlazy2

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subtle dependency on sumtype numeric representation
This commit is contained in:
Yann Collet
2021-12-29 18:51:03 -08:00
parent 7a18d709ae
commit 03903f5701
3 changed files with 65 additions and 13 deletions
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lib/compress/zstd_lazy.c
+12 -12
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@@ -230,7 +230,7 @@ ZSTD_DUBT_findBetterDictMatch (
static size_t
ZSTD_DUBT_findBestMatch(ZSTD_matchState_t* ms,
const BYTE* const ip, const BYTE* const iend,
size_t* offsetPtr,
size_t* offBasePtr,
U32 const mls,
const ZSTD_dictMode_e dictMode)
{
@@ -327,8 +327,8 @@ ZSTD_DUBT_findBestMatch(ZSTD_matchState_t* ms,
if (matchLength > bestLength) {
if (matchLength > matchEndIdx - matchIndex)
matchEndIdx = matchIndex + (U32)matchLength;
if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(curr-matchIndex+1) - ZSTD_highbit32((U32)offsetPtr[0]+1)) )
bestLength = matchLength, *offsetPtr = OFFSET_TO_OFFBASE(curr - matchIndex);
if ( (4*(int)(matchLength-bestLength)) > (int)(ZSTD_highbit32(curr - matchIndex + 1) - ZSTD_highbit32((U32)*offBasePtr)) )
bestLength = matchLength, *offBasePtr = OFFSET_TO_OFFBASE(curr - matchIndex);
if (ip+matchLength == iend) { /* equal : no way to know if inf or sup */
if (dictMode == ZSTD_dictMatchState) {
nbCompares = 0; /* in addition to avoiding checking any
@@ -361,16 +361,16 @@ ZSTD_DUBT_findBestMatch(ZSTD_matchState_t* ms,
if (dictMode == ZSTD_dictMatchState && nbCompares) {
bestLength = ZSTD_DUBT_findBetterDictMatch(
ms, ip, iend,
offsetPtr, bestLength, nbCompares,
offBasePtr, bestLength, nbCompares,
mls, dictMode);
}
assert(matchEndIdx > curr+8); /* ensure nextToUpdate is increased */
ms->nextToUpdate = matchEndIdx - 8; /* skip repetitive patterns */
if (bestLength >= MINMATCH) {
U32 const mIndex = curr - (U32)OFFBASE_TO_OFFSET(*offsetPtr); (void)mIndex;
U32 const mIndex = curr - (U32)OFFBASE_TO_OFFSET(*offBasePtr); (void)mIndex;
DEBUGLOG(8, "ZSTD_DUBT_findBestMatch(%u) : found match of length %u and offsetCode %u (pos %u)",
curr, (U32)bestLength, (U32)*offsetPtr, mIndex);
curr, (U32)bestLength, (U32)*offBasePtr, mIndex);
}
return bestLength;
}
@@ -381,14 +381,14 @@ ZSTD_DUBT_findBestMatch(ZSTD_matchState_t* ms,
FORCE_INLINE_TEMPLATE size_t
ZSTD_BtFindBestMatch( ZSTD_matchState_t* ms,
const BYTE* const ip, const BYTE* const iLimit,
size_t* offsetPtr,
size_t* offBasePtr,
const U32 mls /* template */,
const ZSTD_dictMode_e dictMode)
{
DEBUGLOG(7, "ZSTD_BtFindBestMatch");
if (ip < ms->window.base + ms->nextToUpdate) return 0; /* skipped area */
ZSTD_updateDUBT(ms, ip, iLimit, mls);
return ZSTD_DUBT_findBestMatch(ms, ip, iLimit, offsetPtr, mls, dictMode);
return ZSTD_DUBT_findBestMatch(ms, ip, iLimit, offBasePtr, mls, dictMode);
}
/***********************************
@@ -1337,10 +1337,10 @@ typedef struct {
static size_t ZSTD_BtFindBestMatch_##dictMode##_##mls( \
ZSTD_matchState_t* ms, \
const BYTE* ip, const BYTE* const iLimit, \
size_t* offsetPtr) \
size_t* offBasePtr) \
{ \
assert(MAX(4, MIN(6, ms->cParams.minMatch)) == mls); \
return ZSTD_BtFindBestMatch(ms, ip, iLimit, offsetPtr, mls, ZSTD_##dictMode); \
return ZSTD_BtFindBestMatch(ms, ip, iLimit, offBasePtr, mls, ZSTD_##dictMode);\
} \
static const ZSTD_LazyVTable ZSTD_BtVTable_##dictMode##_##mls = { \
ZSTD_BtFindBestMatch_##dictMode##_##mls \
@@ -1959,7 +1959,7 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
} }
/* search match, depth 1 */
{ size_t ofbCandidate=999999999;
{ size_t ofbCandidate = 999999999;
size_t const ml2 = searchMax(ms, ip, iend, &ofbCandidate);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)ofbCandidate)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offBase) + 4);
@@ -1991,7 +1991,7 @@ size_t ZSTD_compressBlock_lazy_extDict_generic(
} }
/* search match, depth 2 */
{ size_t ofbCandidate=999999999;
{ size_t ofbCandidate = 999999999;
size_t const ml2 = searchMax(ms, ip, iend, &ofbCandidate);
int const gain2 = (int)(ml2*4 - ZSTD_highbit32((U32)ofbCandidate)); /* raw approx */
int const gain1 = (int)(matchLength*4 - ZSTD_highbit32((U32)offBase) + 7);