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

ZSTD_compressBlock_lazy supports more reps

Browse Source
This commit is contained in:
inikep
2016-03-16 12:57:07 +01:00
parent 0ac4a551b9
commit 62d694795d
2 changed files with 95 additions and 47 deletions
Download Patch File Download Diff File Expand all files Collapse all files
lib/zstd_decompress.c
+43 -6
View File
@@ -615,7 +615,7 @@ typedef struct {
FSE_DState_t stateLL;
FSE_DState_t stateOffb;
FSE_DState_t stateML;
size_t prevOffset;
size_t prevOffset[ZSTD_REP_NUM];
const BYTE* dumps;
const BYTE* dumpsEnd;
} seqState_t;
@@ -633,7 +633,7 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState, const U32 mls)
/* Literal length */
litLength = FSE_peakSymbol(&(seqState->stateLL));
prevOffset = litLength ? seq->offset : seqState->prevOffset;
prevOffset = litLength ? seq->offset : seqState->prevOffset[0];
if (litLength == MaxLL) {
U32 add = *dumps++;
if (add < 255) litLength += add;
@@ -656,9 +656,45 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState, const U32 mls)
if (offsetCode==0) nbBits = 0; /* cmove */
offset = offsetPrefix[offsetCode] + BIT_readBits(&(seqState->DStream), nbBits);
if (MEM_32bits()) BIT_reloadDStream(&(seqState->DStream));
if (offsetCode==0) offset = prevOffset; /* repcode, cmove */
else offset -= ZSTD_REP_NUM - 1;
if (offsetCode | !litLength) seqState->prevOffset = seq->offset; /* cmove */
if (offsetCode==0) {
/*
if (offset < LZMAX_NUM_REPS)
{
#if ZSTD_REP_NUM > 1
uint32_t pos = offset;
offset = reps[pos];
if (pos != 0)
{
if (pos != 1)
{
if (pos == 3)
reps[3] = reps[2];
reps[2] = reps[1];
}
reps[1] = reps[0];
reps[0] = offset;
}
#else
offset = reps[0];
#endif
}
else
{
#if ZSTD_REP_NUM > 1
offset -= LZMAX_NUM_REPS - 1;
reps[3] = reps[2];
reps[2] = reps[1];
reps[1] = reps[0];
#endif
reps[0] = offset;
}
*/
offset = prevOffset; /* repcode, cmove */
} else {
if (!litLength) seqState->prevOffset[0] = seq->offset; /* cmove */
offset -= ZSTD_REP_NUM - 1;
}
FSE_decodeSymbol(&(seqState->stateOffb), &(seqState->DStream)); /* update */
// printf("offsetCode=%d nbBits=%d offset=%d\n", offsetCode, nbBits, (int)offset); fflush(stdout);
}
@@ -812,7 +848,8 @@ static size_t ZSTD_decompressSequences(
sequence.offset = REPCODE_STARTVALUE;
seqState.dumps = dumps;
seqState.dumpsEnd = dumps + dumpsLength;
seqState.prevOffset = REPCODE_STARTVALUE;
for (int i=0; i<ZSTD_REP_NUM; i++)
seqState.prevOffset[i] = REPCODE_STARTVALUE;
errorCode = BIT_initDStream(&(seqState.DStream), ip, iend-ip);
if (ERR_isError(errorCode)) return ERROR(corruption_detected);
FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL);