AuroraMiddleware/lz4
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small compression ratio and speed improvement on small files

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This commit is contained in:
Yann Collet 2016-11-07 17:31:38 -08:00
parent 00c6370ad2
commit e9089bcbe4
2 changed files with 13 additions and 17 deletions
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1
NEWS
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@ -2,6 +2,7 @@ v1.7.2
Changed : moved to versioning; package, cli and library have same version number
Improved: Small decompression speed boost
Improved: Small compression speed improvement on 64-bits systems
Improved: Small compression ratio and speed improvement on small files
Improved: Significant speed boost on ARMv6 and ARMv7
New : cli : --rm command
New : cli : file attributes are preserved, by Przemyslaw Skibinki

29
lib/lz4.c
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@ -412,7 +412,7 @@ int LZ4_sizeofState() { return LZ4_STREAMSIZE; }
/*-******************************
* Compression functions
********************************/
static U32 LZ4_hashSequence(U32 sequence, tableType_t const tableType)
static U32 LZ4_hash4(U32 sequence, tableType_t const tableType)
{
if (tableType == byU16)
return ((sequence * 2654435761U) >> ((MINMATCH*8)-(LZ4_HASHLOG+1)));
@ -420,7 +420,7 @@ static U32 LZ4_hashSequence(U32 sequence, tableType_t const tableType)
return ((sequence * 2654435761U) >> ((MINMATCH*8)-LZ4_HASHLOG));
}
static U32 LZ4_hashSequence64(U64 sequence, tableType_t const tableType)
static U32 LZ4_hash5(U64 sequence, tableType_t const tableType)
{
static const U64 prime5bytes = 889523592379ULL;
static const U64 prime8bytes = 11400714785074694791ULL;
@ -431,15 +431,10 @@ static U32 LZ4_hashSequence64(U64 sequence, tableType_t const tableType)
return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
}
static U32 LZ4_hashSequenceT(size_t sequence, tableType_t const tableType)
FORCE_INLINE U32 LZ4_hashPosition(const void* p, tableType_t const tableType)
{
if (LZ4_64bits()) return LZ4_hashSequence64(sequence, tableType);
return LZ4_hashSequence((U32)sequence, tableType);
}
static U32 LZ4_hashPosition(const void* p, tableType_t tableType)
{
return LZ4_hashSequenceT(LZ4_read_ARCH(p), tableType);
if ((LZ4_64bits()) && (tableType == byU32)) return LZ4_hash5(LZ4_read_ARCH(p), tableType);
return LZ4_hash4(LZ4_read32(p), tableType);
}
static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableType_t const tableType, const BYTE* srcBase)
@ -452,7 +447,7 @@ static void LZ4_putPositionOnHash(const BYTE* p, U32 h, void* tableBase, tableTy
}
}
static void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
FORCE_INLINE void LZ4_putPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
{
U32 const h = LZ4_hashPosition(p, tableType);
LZ4_putPositionOnHash(p, h, tableBase, tableType, srcBase);
@ -465,7 +460,7 @@ static const BYTE* LZ4_getPositionOnHash(U32 h, void* tableBase, tableType_t tab
{ const U16* const hashTable = (U16*) tableBase; return hashTable[h] + srcBase; } /* default, to ensure a return */
}
static const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
FORCE_INLINE const BYTE* LZ4_getPosition(const BYTE* p, void* tableBase, tableType_t tableType, const BYTE* srcBase)
{
U32 const h = LZ4_hashPosition(p, tableType);
return LZ4_getPositionOnHash(h, tableBase, tableType, srcBase);
@ -655,7 +650,7 @@ _next_match:
_last_literals:
/* Encode Last Literals */
{ const size_t lastRun = (size_t)(iend - anchor);
{ size_t const lastRun = (size_t)(iend - anchor);
if ( (outputLimited) && /* Check output buffer overflow */
((op - (BYTE*)dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize) )
return 0;
@ -683,12 +678,12 @@ int LZ4_compress_fast_extState(void* state, const char* source, char* dest, int
if (maxOutputSize >= LZ4_compressBound(inputSize)) {
if (inputSize < LZ4_64Klimit)
return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, byU16, noDict, noDictIssue, acceleration);
else
return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration);
return LZ4_compress_generic(state, source, dest, inputSize, 0, notLimited, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration);
} else {
if (inputSize < LZ4_64Klimit)
return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, byU16, noDict, noDictIssue, acceleration);
else
return LZ4_compress_generic(state, source, dest, inputSize, maxOutputSize, limitedOutput, LZ4_64bits() ? byU32 : byPtr, noDict, noDictIssue, acceleration);
}
@ -704,7 +699,7 @@ int LZ4_compress_fast(const char* source, char* dest, int inputSize, int maxOutp
void* const ctxPtr = &ctx;
#endif
int result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
int const result = LZ4_compress_fast_extState(ctxPtr, source, dest, inputSize, maxOutputSize, acceleration);
#if (HEAPMODE)
FREEMEM(ctxPtr);