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Individual memlog values

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This commit is contained in:
Yann Collet 2015-10-24 13:48:37 +01:00
parent ed0a781246
commit 53fff6cd9d
1 changed files with 16 additions and 13 deletions
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29
lib/zstdhc.c
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@ -52,10 +52,10 @@ static const U32 ZSTD_HC_compressionLevel_default = 9;
* Local Constants
***************************************/
#define MINMATCH 4
#define MAXD_LOG 19
#define MAXD_LOG 26
#define MAX_DISTANCE (1 << MAXD_LOG) /* <=== dynamic ? */
#define CHAIN_LOG 16
#define CHAIN_LOG 18
#define CHAIN_SIZE (1<<CHAIN_LOG)
#define CHAIN_MASK (CHAIN_SIZE - 1)
@ -78,7 +78,7 @@ static const U32 g_maxCompressionLevel = MAXD_LOG;
struct ZSTD_HC_CCtx_s
{
U32 hashTable[HASHTABLESIZE];
U16 chainTable[CHAIN_SIZE];
U32 chainTable[CHAIN_SIZE];
const BYTE* end; /* next block here to continue on current prefix */
const BYTE* base; /* All regular indexes relative to this position */
const BYTE* dictBase; /* extDict indexes relative to this position */
@ -124,8 +124,8 @@ static void ZSTD_HC_resetCCtx (ZSTD_HC_CCtx* zc, U32 compressionLevel, const voi
* Local Macros
***************************************/
#define HASH_FUNCTION(u) (((u) * 2654435761U) >> ((MINMATCH*8)-HASH_LOG))
//#define DELTANEXTU16(d) chainTable[(d) & MAXD_MASK] /* flexible, CHAINSIZE dependent */
#define DELTANEXTU16(d) chainTable[(U16)(d)] /* faster, specific to CHAINLOG==16 */
//#define DELTANEXTU16(d) chainTable[(U16)(d)] /* faster, specific to CHAINLOG==16 */
#define DELTANEXT(d) chainTable[(d) & CHAIN_MASK] /* flexible, CHAINSIZE dependent */
static U32 ZSTD_HC_hashPtr(const void* ptr) { return HASH_FUNCTION(MEM_read32(ptr)); }
@ -136,7 +136,7 @@ static U32 ZSTD_HC_hashPtr(const void* ptr) { return HASH_FUNCTION(MEM_read32(pt
/* Update chains up to ip (excluded) */
static void ZSTD_HC_insert (ZSTD_HC_CCtx* zc, const BYTE* ip)
{
U16* chainTable = zc->chainTable;
U32* chainTable = zc->chainTable;
U32* HashTable = zc->hashTable;
const BYTE* const base = zc->base;
const U32 target = (U32)(ip - base);
@ -147,7 +147,7 @@ static void ZSTD_HC_insert (ZSTD_HC_CCtx* zc, const BYTE* ip)
U32 h = ZSTD_HC_hashPtr(base+idx);
size_t delta = idx - HashTable[h];
if (delta>MAX_DISTANCE) delta = MAX_DISTANCE;
DELTANEXTU16(idx) = (U16)delta;
DELTANEXT(idx) = (U32)delta;
HashTable[h] = idx;
idx++;
}
@ -162,7 +162,7 @@ static size_t ZSTD_HC_insertAndFindBestMatch (
const BYTE** matchpos,
const U32 maxNbAttempts)
{
U16* const chainTable = zc->chainTable;
U32* const chainTable = zc->chainTable;
U32* const HashTable = zc->hashTable;
const BYTE* const base = zc->base;
const BYTE* const dictBase = zc->dictBase;
@ -204,8 +204,9 @@ static size_t ZSTD_HC_insertAndFindBestMatch (
if (mlt > ml) { ml = mlt; *matchpos = base + matchIndex; } /* virtual matchpos */
}
}
if (base + matchIndex <= ip - CHAIN_SIZE) break;
matchIndex -= DELTANEXTU16(matchIndex);
matchIndex -= DELTANEXT(matchIndex);
}
return ml;
@ -222,7 +223,7 @@ size_t ZSTD_HC_InsertAndGetWiderMatch (
const BYTE** startpos,
const int maxNbAttempts)
{
U16* const chainTable = zc->chainTable;
U32* const chainTable = zc->chainTable;
U32* const HashTable = zc->hashTable;
const BYTE* const base = zc->base;
const U32 dictLimit = zc->dictLimit;
@ -284,7 +285,7 @@ size_t ZSTD_HC_InsertAndGetWiderMatch (
}
if (base + matchIndex <= ip - CHAIN_SIZE)
matchIndex -= MAX_DISTANCE; /* ensures it gets eliminated on next test */
matchIndex -= DELTANEXTU16(matchIndex);
matchIndex -= DELTANEXT(matchIndex);
}
return longest;
@ -510,8 +511,10 @@ size_t ZSTD_HC_compressCCtx (ZSTD_HC_CCtx* ctx, void* dst, size_t maxDstSize, co
size_t ZSTD_HC_compress(void* dst, size_t maxDstSize, const void* src, size_t srcSize, unsigned compressionLevel)
{
ZSTD_HC_CCtx ctxBody;
return ZSTD_HC_compressCCtx(&ctxBody, dst, maxDstSize, src, srcSize, compressionLevel);
ZSTD_HC_CCtx* ctx = ZSTD_HC_createCCtx();
size_t result = ZSTD_HC_compressCCtx(ctx, dst, maxDstSize, src, srcSize, compressionLevel);
ZSTD_HC_freeCCtx(ctx);
return result;
}