ddidderr/zstd-rs
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

simplified repcodes for lazy_extDict

Browse Source
This commit is contained in:
Yann Collet
2016-07-03 01:28:16 +02:00
parent 9634f67107
commit 302ff036f6
1 changed files with 9 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/compress/zstd_compress.c
+9 -10
View File
@@ -1885,10 +1885,9 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
U32 maxNbAttempts, U32 matchLengthSearch);
searchMax_f searchMax = searchMethod ? ZSTD_BtFindBestMatch_selectMLS_extDict : ZSTD_HcFindBestMatch_extDict_selectMLS;
/* init */
U32 rep[ZSTD_REP_INIT];
{ U32 i; for (i=0; i<ZSTD_REP_INIT; i++) rep[i]=ctx->rep[i]; }
U32 offset_1 = ctx->rep[0], offset_2 = ctx->rep[1];
/* init */
ctx->nextToUpdate3 = ctx->nextToUpdate;
ip += (ip == prefixStart);
@@ -1900,7 +1899,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
U32 current = (U32)(ip-base);
/* check repCode */
{ const U32 repIndex = (U32)(current+1 - rep[0]);
{ const U32 repIndex = (U32)(current+1 - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
@@ -1930,7 +1929,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
current++;
/* check repCode */
if (offset) {
const U32 repIndex = (U32)(current - rep[0]);
const U32 repIndex = (U32)(current - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
@@ -1960,7 +1959,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
current++;
/* check repCode */
if (offset) {
const U32 repIndex = (U32)(current - rep[0]);
const U32 repIndex = (U32)(current - offset_1);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
@@ -1992,7 +1991,7 @@ void ZSTD_compressBlock_lazy_extDict_generic(ZSTD_CCtx* ctx,
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 */
rep[1] = rep[0]; rep[0] = (U32)(offset - ZSTD_REP_MOVE);
offset_2 = offset_1; offset_1 = (U32)(offset - ZSTD_REP_MOVE);
}
/* store sequence */
@@ -2004,7 +2003,7 @@ _storeSequence:
/* check immediate repcode */
while (ip <= ilimit) {
const U32 repIndex = (U32)((ip-base) - rep[1]);
const U32 repIndex = (U32)((ip-base) - offset_2);
const BYTE* const repBase = repIndex < dictLimit ? dictBase : base;
const BYTE* const repMatch = repBase + repIndex;
if (((U32)((dictLimit-1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */
@@ -2012,7 +2011,7 @@ _storeSequence:
/* repcode detected we should take it */
const BYTE* const repEnd = repIndex < dictLimit ? dictEnd : iend;
matchLength = ZSTD_count_2segments(ip+EQUAL_READ32, repMatch+EQUAL_READ32, iend, repEnd, prefixStart) + EQUAL_READ32;
offset = rep[1]; rep[1] = rep[0]; rep[0] = (U32)offset; /* swap offset history */
offset = offset_2; offset_2 = offset_1; offset_1 = (U32)offset; /* swap offset history */
ZSTD_storeSeq(seqStorePtr, 0, anchor, 0, matchLength-MINMATCH);
ip += matchLength;
anchor = ip;
@@ -2022,7 +2021,7 @@ _storeSequence:
} }
/* Save reps for next block */
ctx->savedRep[0] = rep[0]; ctx->savedRep[1] = rep[1]; ctx->savedRep[2] = rep[2];
ctx->savedRep[0] = offset_1; ctx->savedRep[1] = offset_2;
/* Last Literals */
{ size_t const lastLLSize = iend - anchor;