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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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53
contrib/seekable_format/zstdseek_decompress.c
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@ -23,13 +23,64 @@
# endif
#endif
/* ************************************************************
* Detect POSIX version
* PLATFORM_POSIX_VERSION = 0 for non-Unix e.g. Windows
* PLATFORM_POSIX_VERSION = 1 for Unix-like but non-POSIX
* PLATFORM_POSIX_VERSION > 1 is equal to found _POSIX_VERSION
* Value of PLATFORM_POSIX_VERSION can be forced on command line
***************************************************************/
#ifndef PLATFORM_POSIX_VERSION
# if (defined(__APPLE__) && defined(__MACH__)) || defined(__SVR4) || defined(_AIX) || defined(__hpux) /* POSIX.1-2001 (SUSv3) conformant */ \
|| defined(__DragonFly__) || defined(__FreeBSD__) || defined(__NetBSD__) || defined(__OpenBSD__) /* BSD distros */
/* exception rule : force posix version to 200112L,
* note: it's better to use unistd.h's _POSIX_VERSION whenever possible */
# define PLATFORM_POSIX_VERSION 200112L
/* try to determine posix version through official unistd.h's _POSIX_VERSION (http://pubs.opengroup.org/onlinepubs/7908799/xsh/unistd.h.html).
* note : there is no simple way to know in advance if <unistd.h> is present or not on target system,
* Posix specification mandates its presence and its content, but target system must respect this spec.
* It's necessary to _not_ #include <unistd.h> whenever target OS is not unix-like
* otherwise it will block preprocessing stage.
* The following list of build macros tries to "guess" if target OS is likely unix-like, and therefore can #include <unistd.h>
*/
# elif !defined(_WIN32) \
&& ( defined(__unix__) || defined(__unix) \
|| defined(__midipix__) || defined(__VMS) || defined(__HAIKU__) )
# if defined(__linux__) || defined(__linux) || defined(__CYGWIN__)
# ifndef _POSIX_C_SOURCE
# define _POSIX_C_SOURCE 200809L /* feature test macro : https://www.gnu.org/software/libc/manual/html_node/Feature-Test-Macros.html */
# endif
# endif
# include <unistd.h> /* declares _POSIX_VERSION */
# if defined(_POSIX_VERSION) /* POSIX compliant */
# define PLATFORM_POSIX_VERSION _POSIX_VERSION
# else
# define PLATFORM_POSIX_VERSION 1
# endif
# ifdef __UCLIBC__
# ifndef __USE_MISC
# define __USE_MISC /* enable st_mtim on uclibc */
# endif
# endif
# else /* non-unix target platform (like Windows) */
# define PLATFORM_POSIX_VERSION 0
# endif
#endif /* PLATFORM_POSIX_VERSION */
/* ************************************************************
* Avoid fseek()'s 2GiB barrier with MSVC, macOS, *BSD, MinGW
***************************************************************/
#if defined(_MSC_VER) && _MSC_VER >= 1400
# define LONG_SEEK _fseeki64
#elif !defined(__64BIT__) && (PLATFORM_POSIX_VERSION >= 200112L) /* No point defining Large file for 64 bit */
# define LONG_SEEK fseeko
# define LONG_SEEK fseeko
#elif defined(__MINGW32__) && !defined(__STRICT_ANSI__) && !defined(__NO_MINGW_LFS) && defined(__MSVCRT__)
# define LONG_SEEK fseeko64
#elif defined(_WIN32) && !defined(__DJGPP__)

24
lib/compress/zstd_lazy.c
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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);

1
tests/regression/.gitignore vendored
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@ -1,3 +1,4 @@
# regression test artifacts
data-cache
cache
test