incorporate ZSTD_decodeSequenceLong() within zstd_decompress.c
Yann Collet
parent
17626ba56e
commit
a166eae1ba
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@ -1333,6 +1333,90 @@ ZSTD_decodeSequence_default(seqState_t* seqState, const ZSTD_longOffset_e longOf
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return ZSTD_decodeSequence_body(seqState, longOffsets);
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}
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FORCE_INLINE_TEMPLATE seq_t
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ZSTD_decodeSequenceLong_body(seqState_t* seqState, ZSTD_longOffset_e const longOffsets)
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{
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seq_t seq;
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U32 const llBits = seqState->stateLL.table[seqState->stateLL.state].nbAdditionalBits;
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U32 const mlBits = seqState->stateML.table[seqState->stateML.state].nbAdditionalBits;
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U32 const ofBits = seqState->stateOffb.table[seqState->stateOffb.state].nbAdditionalBits;
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U32 const totalBits = llBits+mlBits+ofBits;
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U32 const llBase = seqState->stateLL.table[seqState->stateLL.state].baseValue;
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U32 const mlBase = seqState->stateML.table[seqState->stateML.state].baseValue;
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U32 const ofBase = seqState->stateOffb.table[seqState->stateOffb.state].baseValue;
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/* sequence */
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{ size_t offset;
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if (!ofBits)
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offset = 0;
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else {
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ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
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ZSTD_STATIC_ASSERT(LONG_OFFSETS_MAX_EXTRA_BITS_32 == 5);
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assert(ofBits <= MaxOff);
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if (MEM_32bits() && longOffsets) {
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U32 const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN_32-1);
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offset = ofBase + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
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if (MEM_32bits() || extraBits) BIT_reloadDStream(&seqState->DStream);
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if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits);
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} else {
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offset = ofBase + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
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if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream);
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}
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}
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if (ofBits <= 1) {
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offset += (llBase==0);
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if (offset) {
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size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
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temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */
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if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1];
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seqState->prevOffset[1] = seqState->prevOffset[0];
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seqState->prevOffset[0] = offset = temp;
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} else {
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offset = seqState->prevOffset[0];
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}
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} else {
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seqState->prevOffset[2] = seqState->prevOffset[1];
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seqState->prevOffset[1] = seqState->prevOffset[0];
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seqState->prevOffset[0] = offset;
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}
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seq.offset = offset;
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}
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seq.matchLength = mlBase + ((mlBits>0) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */
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if (MEM_32bits() && (mlBits+llBits >= STREAM_ACCUMULATOR_MIN_32-LONG_OFFSETS_MAX_EXTRA_BITS_32))
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BIT_reloadDStream(&seqState->DStream);
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if (MEM_64bits() && (totalBits >= STREAM_ACCUMULATOR_MIN_64-(LLFSELog+MLFSELog+OffFSELog)))
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BIT_reloadDStream(&seqState->DStream);
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/* Verify that there is enough bits to read the rest of the data in 64-bit mode. */
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ZSTD_STATIC_ASSERT(16+LLFSELog+MLFSELog+OffFSELog < STREAM_ACCUMULATOR_MIN_64);
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seq.litLength = llBase + ((llBits>0) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */
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if (MEM_32bits())
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BIT_reloadDStream(&seqState->DStream);
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{ size_t const pos = seqState->pos + seq.litLength;
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const BYTE* const matchBase = (seq.offset > pos) ? seqState->dictEnd : seqState->prefixStart;
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seq.match = matchBase + pos - seq.offset; /* note : this operation can overflow when seq.offset is really too large, which can only happen when input is corrupted.
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* No consequence though : no memory access will occur, overly large offset will be detected in ZSTD_execSequenceLong() */
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seqState->pos = pos + seq.matchLength;
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}
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/* ANS state update */
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ZSTD_updateFseState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */
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ZSTD_updateFseState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */
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if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
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ZSTD_updateFseState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */
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return seq;
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}
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static seq_t
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ZSTD_decodeSequenceLong_default(seqState_t* seqState, ZSTD_longOffset_e const longOffsets)
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{
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return ZSTD_decodeSequenceLong_body(seqState, longOffsets);
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}
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#define FUNCTION(fn) fn##_default
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#define TARGET
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@ -1348,6 +1432,12 @@ ZSTD_decodeSequence_bmi2(seqState_t* seqState, const ZSTD_longOffset_e longOffse
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return ZSTD_decodeSequence_body(seqState, longOffsets);
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}
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static TARGET_ATTRIBUTE("bmi2") seq_t
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ZSTD_decodeSequenceLong_bmi2(seqState_t* seqState, ZSTD_longOffset_e const longOffsets)
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{
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return ZSTD_decodeSequenceLong_body(seqState, longOffsets);
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}
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#define FUNCTION(fn) fn##_bmi2
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#define TARGET TARGET_ATTRIBUTE("bmi2")
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#include "zstd_decompress_impl.h"
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@ -18,85 +18,6 @@
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HINT_INLINE seq_t
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FUNCTION(ZSTD_decodeSequenceLong)(seqState_t* seqState, ZSTD_longOffset_e const longOffsets)
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{
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seq_t seq;
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U32 const llBits = seqState->stateLL.table[seqState->stateLL.state].nbAdditionalBits;
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U32 const mlBits = seqState->stateML.table[seqState->stateML.state].nbAdditionalBits;
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U32 const ofBits = seqState->stateOffb.table[seqState->stateOffb.state].nbAdditionalBits;
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U32 const totalBits = llBits+mlBits+ofBits;
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U32 const llBase = seqState->stateLL.table[seqState->stateLL.state].baseValue;
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U32 const mlBase = seqState->stateML.table[seqState->stateML.state].baseValue;
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U32 const ofBase = seqState->stateOffb.table[seqState->stateOffb.state].baseValue;
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/* sequence */
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{ size_t offset;
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if (!ofBits)
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offset = 0;
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else {
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ZSTD_STATIC_ASSERT(ZSTD_lo_isLongOffset == 1);
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ZSTD_STATIC_ASSERT(LONG_OFFSETS_MAX_EXTRA_BITS_32 == 5);
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assert(ofBits <= MaxOff);
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if (MEM_32bits() && longOffsets) {
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U32 const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN_32-1);
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offset = ofBase + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits);
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if (MEM_32bits() || extraBits) BIT_reloadDStream(&seqState->DStream);
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if (extraBits) offset += BIT_readBitsFast(&seqState->DStream, extraBits);
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} else {
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offset = ofBase + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */
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if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream);
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}
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}
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if (ofBits <= 1) {
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offset += (llBase==0);
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if (offset) {
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size_t temp = (offset==3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset];
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temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */
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if (offset != 1) seqState->prevOffset[2] = seqState->prevOffset[1];
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seqState->prevOffset[1] = seqState->prevOffset[0];
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seqState->prevOffset[0] = offset = temp;
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} else {
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offset = seqState->prevOffset[0];
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}
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} else {
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seqState->prevOffset[2] = seqState->prevOffset[1];
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seqState->prevOffset[1] = seqState->prevOffset[0];
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seqState->prevOffset[0] = offset;
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}
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seq.offset = offset;
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}
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seq.matchLength = mlBase + ((mlBits>0) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */
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if (MEM_32bits() && (mlBits+llBits >= STREAM_ACCUMULATOR_MIN_32-LONG_OFFSETS_MAX_EXTRA_BITS_32))
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BIT_reloadDStream(&seqState->DStream);
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if (MEM_64bits() && (totalBits >= STREAM_ACCUMULATOR_MIN_64-(LLFSELog+MLFSELog+OffFSELog)))
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BIT_reloadDStream(&seqState->DStream);
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/* Verify that there is enough bits to read the rest of the data in 64-bit mode. */
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ZSTD_STATIC_ASSERT(16+LLFSELog+MLFSELog+OffFSELog < STREAM_ACCUMULATOR_MIN_64);
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seq.litLength = llBase + ((llBits>0) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */
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if (MEM_32bits())
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BIT_reloadDStream(&seqState->DStream);
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{ size_t const pos = seqState->pos + seq.litLength;
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const BYTE* const matchBase = (seq.offset > pos) ? seqState->dictEnd : seqState->prefixStart;
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seq.match = matchBase + pos - seq.offset; /* note : this operation can overflow when seq.offset is really too large, which can only happen when input is corrupted.
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* No consequence though : no memory access will occur, overly large offset will be detected in ZSTD_execSequenceLong() */
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seqState->pos = pos + seq.matchLength;
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}
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/* ANS state update */
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ZSTD_updateFseState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */
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ZSTD_updateFseState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */
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if (MEM_32bits()) BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */
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ZSTD_updateFseState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */
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return seq;
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}
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static TARGET void
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FUNCTION(ZSTD_initFseState)(ZSTD_fseState* DStatePtr, BIT_DStream_t* bitD, const ZSTD_seqSymbol* dt)
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{
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