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-rw-r--r--vendor/github.com/klauspost/compress/huff0/bitwriter.go13
-rw-r--r--vendor/github.com/klauspost/compress/huff0/compress.go70
-rw-r--r--vendor/github.com/klauspost/compress/huff0/huff0.go7
-rw-r--r--vendor/github.com/klauspost/compress/zstd/README.md4
-rw-r--r--vendor/github.com/klauspost/compress/zstd/blockenc.go33
-rw-r--r--vendor/github.com/klauspost/compress/zstd/decoder.go29
-rw-r--r--vendor/github.com/klauspost/compress/zstd/enc_dfast.go313
-rw-r--r--vendor/github.com/klauspost/compress/zstd/enc_fast.go245
-rw-r--r--vendor/github.com/klauspost/compress/zstd/encoder.go71
9 files changed, 726 insertions, 59 deletions
diff --git a/vendor/github.com/klauspost/compress/huff0/bitwriter.go b/vendor/github.com/klauspost/compress/huff0/bitwriter.go
index ec0c3fc53..bda4021ef 100644
--- a/vendor/github.com/klauspost/compress/huff0/bitwriter.go
+++ b/vendor/github.com/klauspost/compress/huff0/bitwriter.go
@@ -38,7 +38,7 @@ func (b *bitWriter) addBits16Clean(value uint16, bits uint8) {
b.nBits += bits
}
-// addBits16Clean will add up to 16 bits. value may not contain more set bits than indicated.
+// encSymbol will add up to 16 bits. value may not contain more set bits than indicated.
// It will not check if there is space for them, so the caller must ensure that it has flushed recently.
func (b *bitWriter) encSymbol(ct cTable, symbol byte) {
enc := ct[symbol]
@@ -46,6 +46,17 @@ func (b *bitWriter) encSymbol(ct cTable, symbol byte) {
b.nBits += enc.nBits
}
+// encTwoSymbols will add up to 32 bits. value may not contain more set bits than indicated.
+// It will not check if there is space for them, so the caller must ensure that it has flushed recently.
+func (b *bitWriter) encTwoSymbols(ct cTable, av, bv byte) {
+ encA := ct[av]
+ encB := ct[bv]
+ sh := b.nBits & 63
+ combined := uint64(encA.val) | (uint64(encB.val) << (encA.nBits & 63))
+ b.bitContainer |= combined << sh
+ b.nBits += encA.nBits + encB.nBits
+}
+
// addBits16ZeroNC will add up to 16 bits.
// It will not check if there is space for them,
// so the caller must ensure that it has flushed recently.
diff --git a/vendor/github.com/klauspost/compress/huff0/compress.go b/vendor/github.com/klauspost/compress/huff0/compress.go
index 51e00aaeb..0843cb014 100644
--- a/vendor/github.com/klauspost/compress/huff0/compress.go
+++ b/vendor/github.com/klauspost/compress/huff0/compress.go
@@ -80,9 +80,12 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
if s.Reuse == ReusePolicyPrefer && canReuse {
keepTable := s.cTable
+ keepTL := s.actualTableLog
s.cTable = s.prevTable
+ s.actualTableLog = s.prevTableLog
s.Out, err = compressor(in)
s.cTable = keepTable
+ s.actualTableLog = keepTL
if err == nil && len(s.Out) < wantSize {
s.OutData = s.Out
return s.Out, true, nil
@@ -92,7 +95,6 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
}
// Calculate new table.
- s.optimalTableLog()
err = s.buildCTable()
if err != nil {
return nil, false, err
@@ -109,9 +111,15 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
if oldSize <= hSize+newSize || hSize+12 >= wantSize {
// Retain cTable even if we re-use.
keepTable := s.cTable
+ keepTL := s.actualTableLog
+
s.cTable = s.prevTable
+ s.actualTableLog = s.prevTableLog
s.Out, err = compressor(in)
+
+ // Restore ctable.
s.cTable = keepTable
+ s.actualTableLog = keepTL
if err != nil {
return nil, false, err
}
@@ -142,7 +150,7 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
return nil, false, ErrIncompressible
}
// Move current table into previous.
- s.prevTable, s.cTable = s.cTable, s.prevTable[:0]
+ s.prevTable, s.prevTableLog, s.cTable = s.cTable, s.actualTableLog, s.prevTable[:0]
s.OutData = s.Out[len(s.OutTable):]
return s.Out, false, nil
}
@@ -163,28 +171,23 @@ func (s *Scratch) compress1xDo(dst, src []byte) ([]byte, error) {
for i := len(src) & 3; i > 0; i-- {
bw.encSymbol(cTable, src[n+i-1])
}
+ n -= 4
if s.actualTableLog <= 8 {
- n -= 4
for ; n >= 0; n -= 4 {
tmp := src[n : n+4]
// tmp should be len 4
bw.flush32()
- bw.encSymbol(cTable, tmp[3])
- bw.encSymbol(cTable, tmp[2])
- bw.encSymbol(cTable, tmp[1])
- bw.encSymbol(cTable, tmp[0])
+ bw.encTwoSymbols(cTable, tmp[3], tmp[2])
+ bw.encTwoSymbols(cTable, tmp[1], tmp[0])
}
} else {
- n -= 4
for ; n >= 0; n -= 4 {
tmp := src[n : n+4]
// tmp should be len 4
bw.flush32()
- bw.encSymbol(cTable, tmp[3])
- bw.encSymbol(cTable, tmp[2])
+ bw.encTwoSymbols(cTable, tmp[3], tmp[2])
bw.flush32()
- bw.encSymbol(cTable, tmp[1])
- bw.encSymbol(cTable, tmp[0])
+ bw.encTwoSymbols(cTable, tmp[1], tmp[0])
}
}
err := bw.close()
@@ -322,9 +325,26 @@ func (s *Scratch) canUseTable(c cTable) bool {
return true
}
+func (s *Scratch) validateTable(c cTable) bool {
+ if len(c) < int(s.symbolLen) {
+ return false
+ }
+ for i, v := range s.count[:s.symbolLen] {
+ if v != 0 {
+ if c[i].nBits == 0 {
+ return false
+ }
+ if c[i].nBits > s.actualTableLog {
+ return false
+ }
+ }
+ }
+ return true
+}
+
// minTableLog provides the minimum logSize to safely represent a distribution.
func (s *Scratch) minTableLog() uint8 {
- minBitsSrc := highBit32(uint32(s.br.remain()-1)) + 1
+ minBitsSrc := highBit32(uint32(s.br.remain())) + 1
minBitsSymbols := highBit32(uint32(s.symbolLen-1)) + 2
if minBitsSrc < minBitsSymbols {
return uint8(minBitsSrc)
@@ -336,7 +356,7 @@ func (s *Scratch) minTableLog() uint8 {
func (s *Scratch) optimalTableLog() {
tableLog := s.TableLog
minBits := s.minTableLog()
- maxBitsSrc := uint8(highBit32(uint32(s.br.remain()-1))) - 2
+ maxBitsSrc := uint8(highBit32(uint32(s.br.remain()-1))) - 1
if maxBitsSrc < tableLog {
// Accuracy can be reduced
tableLog = maxBitsSrc
@@ -363,6 +383,7 @@ type cTableEntry struct {
const huffNodesMask = huffNodesLen - 1
func (s *Scratch) buildCTable() error {
+ s.optimalTableLog()
s.huffSort()
if cap(s.cTable) < maxSymbolValue+1 {
s.cTable = make([]cTableEntry, s.symbolLen, maxSymbolValue+1)
@@ -439,7 +460,7 @@ func (s *Scratch) buildCTable() error {
return fmt.Errorf("internal error: maxNbBits (%d) > tableLogMax (%d)", maxNbBits, tableLogMax)
}
var nbPerRank [tableLogMax + 1]uint16
- var valPerRank [tableLogMax + 1]uint16
+ var valPerRank [16]uint16
for _, v := range huffNode[:nonNullRank+1] {
nbPerRank[v.nbBits]++
}
@@ -455,16 +476,17 @@ func (s *Scratch) buildCTable() error {
}
// push nbBits per symbol, symbol order
- // TODO: changed `s.symbolLen` -> `nonNullRank+1` (micro-opt)
for _, v := range huffNode[:nonNullRank+1] {
s.cTable[v.symbol].nBits = v.nbBits
}
// assign value within rank, symbol order
- for n, val := range s.cTable[:s.symbolLen] {
- v := valPerRank[val.nBits]
- s.cTable[n].val = v
- valPerRank[val.nBits] = v + 1
+ t := s.cTable[:s.symbolLen]
+ for n, val := range t {
+ nbits := val.nBits & 15
+ v := valPerRank[nbits]
+ t[n].val = v
+ valPerRank[nbits] = v + 1
}
return nil
@@ -488,10 +510,12 @@ func (s *Scratch) huffSort() {
r := highBit32(v+1) & 31
rank[r].base++
}
- for n := 30; n > 0; n-- {
+ // maxBitLength is log2(BlockSizeMax) + 1
+ const maxBitLength = 18 + 1
+ for n := maxBitLength; n > 0; n-- {
rank[n-1].base += rank[n].base
}
- for n := range rank[:] {
+ for n := range rank[:maxBitLength] {
rank[n].current = rank[n].base
}
for n, c := range s.count[:s.symbolLen] {
@@ -510,7 +534,7 @@ func (s *Scratch) huffSort() {
}
func (s *Scratch) setMaxHeight(lastNonNull int) uint8 {
- maxNbBits := s.TableLog
+ maxNbBits := s.actualTableLog
huffNode := s.nodes[1 : huffNodesLen+1]
//huffNode = huffNode[: huffNodesLen]
diff --git a/vendor/github.com/klauspost/compress/huff0/huff0.go b/vendor/github.com/klauspost/compress/huff0/huff0.go
index 6bc23bbf0..53249df05 100644
--- a/vendor/github.com/klauspost/compress/huff0/huff0.go
+++ b/vendor/github.com/klauspost/compress/huff0/huff0.go
@@ -83,7 +83,7 @@ type Scratch struct {
MaxSymbolValue uint8
// TableLog will attempt to override the tablelog for the next block.
- // Must be <= 11.
+ // Must be <= 11 and >= 5.
TableLog uint8
// Reuse will specify the reuse policy
@@ -105,6 +105,7 @@ type Scratch struct {
maxCount int // count of the most probable symbol
clearCount bool // clear count
actualTableLog uint8 // Selected tablelog.
+ prevTableLog uint8 // Tablelog for previous table
prevTable cTable // Table used for previous compression.
cTable cTable // compression table
dt dTable // decompression table
@@ -127,8 +128,8 @@ func (s *Scratch) prepare(in []byte) (*Scratch, error) {
if s.TableLog == 0 {
s.TableLog = tableLogDefault
}
- if s.TableLog > tableLogMax {
- return nil, fmt.Errorf("tableLog (%d) > maxTableLog (%d)", s.TableLog, tableLogMax)
+ if s.TableLog > tableLogMax || s.TableLog < minTablelog {
+ return nil, fmt.Errorf(" invalid tableLog %d (%d -> %d)", s.TableLog, minTablelog, tableLogMax)
}
if s.MaxDecodedSize <= 0 || s.MaxDecodedSize > BlockSizeMax {
s.MaxDecodedSize = BlockSizeMax
diff --git a/vendor/github.com/klauspost/compress/zstd/README.md b/vendor/github.com/klauspost/compress/zstd/README.md
index 52dc0aee3..bc977a302 100644
--- a/vendor/github.com/klauspost/compress/zstd/README.md
+++ b/vendor/github.com/klauspost/compress/zstd/README.md
@@ -36,7 +36,7 @@ so as always, testing is recommended.
For now, a high speed (fastest) and medium-fast (default) compressor has been implemented.
The "Fastest" compression ratio is roughly equivalent to zstd level 1.
-The "Default" compression ration is roughly equivalent to zstd level 3 (default).
+The "Default" compression ratio is roughly equivalent to zstd level 3 (default).
In terms of speed, it is typically 2x as fast as the stdlib deflate/gzip in its fastest mode.
The compression ratio compared to stdlib is around level 3, but usually 3x as fast.
@@ -390,4 +390,4 @@ For sending files for reproducing errors use a service like [goobox](https://goo
For general feedback and experience reports, feel free to open an issue or write me on [Twitter](https://twitter.com/sh0dan).
-This package includes the excellent [`github.com/cespare/xxhash`](https://github.com/cespare/xxhash) package Copyright (c) 2016 Caleb Spare. \ No newline at end of file
+This package includes the excellent [`github.com/cespare/xxhash`](https://github.com/cespare/xxhash) package Copyright (c) 2016 Caleb Spare.
diff --git a/vendor/github.com/klauspost/compress/zstd/blockenc.go b/vendor/github.com/klauspost/compress/zstd/blockenc.go
index 99eccda11..507757d52 100644
--- a/vendor/github.com/klauspost/compress/zstd/blockenc.go
+++ b/vendor/github.com/klauspost/compress/zstd/blockenc.go
@@ -299,6 +299,20 @@ func (b *blockEnc) encodeRaw(a []byte) {
}
}
+// encodeRaw can be used to set the output to a raw representation of supplied bytes.
+func (b *blockEnc) encodeRawTo(dst, src []byte) []byte {
+ var bh blockHeader
+ bh.setLast(b.last)
+ bh.setSize(uint32(len(src)))
+ bh.setType(blockTypeRaw)
+ dst = bh.appendTo(dst)
+ dst = append(dst, src...)
+ if debug {
+ println("Adding RAW block, length", len(src))
+ }
+ return dst
+}
+
// encodeLits can be used if the block is only litLen.
func (b *blockEnc) encodeLits(raw bool) error {
var bh blockHeader
@@ -324,18 +338,10 @@ func (b *blockEnc) encodeLits(raw bool) error {
if len(b.literals) >= 1024 {
// Use 4 Streams.
out, reUsed, err = huff0.Compress4X(b.literals, b.litEnc)
- if len(out) > len(b.literals)-len(b.literals)>>4 {
- // Bail out of compression is too little.
- err = huff0.ErrIncompressible
- }
} else if len(b.literals) > 32 {
// Use 1 stream
single = true
out, reUsed, err = huff0.Compress1X(b.literals, b.litEnc)
- if len(out) > len(b.literals)-len(b.literals)>>4 {
- // Bail out of compression is too little.
- err = huff0.ErrIncompressible
- }
} else {
err = huff0.ErrIncompressible
}
@@ -437,7 +443,7 @@ func fuzzFseEncoder(data []byte) int {
return 1
}
-// encode will encode the block and put the output in b.output.
+// encode will encode the block and append the output in b.output.
func (b *blockEnc) encode(raw bool) error {
if len(b.sequences) == 0 {
return b.encodeLits(raw)
@@ -451,6 +457,8 @@ func (b *blockEnc) encode(raw bool) error {
var lh literalsHeader
bh.setLast(b.last)
bh.setType(blockTypeCompressed)
+ // Store offset of the block header. Needed when we know the size.
+ bhOffset := len(b.output)
b.output = bh.appendTo(b.output)
var (
@@ -468,6 +476,7 @@ func (b *blockEnc) encode(raw bool) error {
} else {
err = huff0.ErrIncompressible
}
+
switch err {
case huff0.ErrIncompressible:
lh.setType(literalsBlockRaw)
@@ -735,18 +744,18 @@ func (b *blockEnc) encode(raw bool) error {
}
b.output = wr.out
- if len(b.output)-3 >= b.size {
+ if len(b.output)-3-bhOffset >= b.size {
// Maybe even add a bigger margin.
b.litEnc.Reuse = huff0.ReusePolicyNone
return errIncompressible
}
// Size is output minus block header.
- bh.setSize(uint32(len(b.output)) - 3)
+ bh.setSize(uint32(len(b.output)-bhOffset) - 3)
if debug {
println("Rewriting block header", bh)
}
- _ = bh.appendTo(b.output[:0])
+ _ = bh.appendTo(b.output[bhOffset:bhOffset])
b.coders.setPrev(llEnc, mlEnc, ofEnc)
return nil
}
diff --git a/vendor/github.com/klauspost/compress/zstd/decoder.go b/vendor/github.com/klauspost/compress/zstd/decoder.go
index 1de94eef0..35a3cda91 100644
--- a/vendor/github.com/klauspost/compress/zstd/decoder.go
+++ b/vendor/github.com/klauspost/compress/zstd/decoder.go
@@ -388,6 +388,35 @@ func (d *Decoder) Close() {
d.current.err = ErrDecoderClosed
}
+// IOReadCloser returns the decoder as an io.ReadCloser for convenience.
+// Any changes to the decoder will be reflected, so the returned ReadCloser
+// can be reused along with the decoder.
+// io.WriterTo is also supported by the returned ReadCloser.
+func (d *Decoder) IOReadCloser() io.ReadCloser {
+ return closeWrapper{d: d}
+}
+
+// closeWrapper wraps a function call as a closer.
+type closeWrapper struct {
+ d *Decoder
+}
+
+// WriteTo forwards WriteTo calls to the decoder.
+func (c closeWrapper) WriteTo(w io.Writer) (n int64, err error) {
+ return c.d.WriteTo(w)
+}
+
+// Read forwards read calls to the decoder.
+func (c closeWrapper) Read(p []byte) (n int, err error) {
+ return c.d.Read(p)
+}
+
+// Close closes the decoder.
+func (c closeWrapper) Close() error {
+ c.d.Close()
+ return nil
+}
+
type decodeOutput struct {
d *blockDec
b []byte
diff --git a/vendor/github.com/klauspost/compress/zstd/enc_dfast.go b/vendor/github.com/klauspost/compress/zstd/enc_dfast.go
index 2f41bcd0d..ee3b09b02 100644
--- a/vendor/github.com/klauspost/compress/zstd/enc_dfast.go
+++ b/vendor/github.com/klauspost/compress/zstd/enc_dfast.go
@@ -411,3 +411,316 @@ encodeLoop:
println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
}
}
+
+// EncodeNoHist will encode a block with no history and no following blocks.
+// Most notable difference is that src will not be copied for history and
+// we do not need to check for max match length.
+func (e *doubleFastEncoder) EncodeNoHist(blk *blockEnc, src []byte) {
+ const (
+ // Input margin is the number of bytes we read (8)
+ // and the maximum we will read ahead (2)
+ inputMargin = 8 + 2
+ minNonLiteralBlockSize = 16
+ )
+
+ // Protect against e.cur wraparound.
+ if e.cur > (1<<30)+e.maxMatchOff {
+ for i := range e.table[:] {
+ e.table[i] = tableEntry{}
+ }
+ for i := range e.longTable[:] {
+ e.longTable[i] = tableEntry{}
+ }
+ e.cur = e.maxMatchOff
+ }
+
+ s := int32(0)
+ blk.size = len(src)
+ if len(src) < minNonLiteralBlockSize {
+ blk.extraLits = len(src)
+ blk.literals = blk.literals[:len(src)]
+ copy(blk.literals, src)
+ return
+ }
+
+ // Override src
+ sLimit := int32(len(src)) - inputMargin
+ // stepSize is the number of bytes to skip on every main loop iteration.
+ // It should be >= 1.
+ stepSize := int32(e.o.targetLength)
+ if stepSize == 0 {
+ stepSize++
+ }
+
+ const kSearchStrength = 8
+
+ // nextEmit is where in src the next emitLiteral should start from.
+ nextEmit := s
+ cv := load6432(src, s)
+
+ // Relative offsets
+ offset1 := int32(blk.recentOffsets[0])
+ offset2 := int32(blk.recentOffsets[1])
+
+ addLiterals := func(s *seq, until int32) {
+ if until == nextEmit {
+ return
+ }
+ blk.literals = append(blk.literals, src[nextEmit:until]...)
+ s.litLen = uint32(until - nextEmit)
+ }
+ if debug {
+ println("recent offsets:", blk.recentOffsets)
+ }
+
+encodeLoop:
+ for {
+ var t int32
+ for {
+
+ nextHashS := hash5(cv, dFastShortTableBits)
+ nextHashL := hash8(cv, dFastLongTableBits)
+ candidateL := e.longTable[nextHashL]
+ candidateS := e.table[nextHashS]
+
+ const repOff = 1
+ repIndex := s - offset1 + repOff
+ entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
+ e.longTable[nextHashL] = entry
+ e.table[nextHashS] = entry
+
+ if len(blk.sequences) > 2 {
+ if load3232(src, repIndex) == uint32(cv>>(repOff*8)) {
+ // Consider history as well.
+ var seq seq
+ //length := 4 + e.matchlen(s+4+repOff, repIndex+4, src)
+ length := 4 + int32(matchLen(src[s+4+repOff:], src[repIndex+4:]))
+
+ seq.matchLen = uint32(length - zstdMinMatch)
+
+ // We might be able to match backwards.
+ // Extend as long as we can.
+ start := s + repOff
+ // We end the search early, so we don't risk 0 literals
+ // and have to do special offset treatment.
+ startLimit := nextEmit + 1
+
+ tMin := s - e.maxMatchOff
+ if tMin < 0 {
+ tMin = 0
+ }
+ for repIndex > tMin && start > startLimit && src[repIndex-1] == src[start-1] {
+ repIndex--
+ start--
+ seq.matchLen++
+ }
+ addLiterals(&seq, start)
+
+ // rep 0
+ seq.offset = 1
+ if debugSequences {
+ println("repeat sequence", seq, "next s:", s)
+ }
+ blk.sequences = append(blk.sequences, seq)
+ s += length + repOff
+ nextEmit = s
+ if s >= sLimit {
+ if debug {
+ println("repeat ended", s, length)
+
+ }
+ break encodeLoop
+ }
+ cv = load6432(src, s)
+ continue
+ }
+ }
+ // Find the offsets of our two matches.
+ coffsetL := s - (candidateL.offset - e.cur)
+ coffsetS := s - (candidateS.offset - e.cur)
+
+ // Check if we have a long match.
+ if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
+ // Found a long match, likely at least 8 bytes.
+ // Reference encoder checks all 8 bytes, we only check 4,
+ // but the likelihood of both the first 4 bytes and the hash matching should be enough.
+ t = candidateL.offset - e.cur
+ if debug && s <= t {
+ panic("s <= t")
+ }
+ if debug && s-t > e.maxMatchOff {
+ panic("s - t >e.maxMatchOff")
+ }
+ if debugMatches {
+ println("long match")
+ }
+ break
+ }
+
+ // Check if we have a short match.
+ if coffsetS < e.maxMatchOff && uint32(cv) == candidateS.val {
+ // found a regular match
+ // See if we can find a long match at s+1
+ const checkAt = 1
+ cv := load6432(src, s+checkAt)
+ nextHashL = hash8(cv, dFastLongTableBits)
+ candidateL = e.longTable[nextHashL]
+ coffsetL = s - (candidateL.offset - e.cur) + checkAt
+
+ // We can store it, since we have at least a 4 byte match.
+ e.longTable[nextHashL] = tableEntry{offset: s + checkAt + e.cur, val: uint32(cv)}
+ if coffsetL < e.maxMatchOff && uint32(cv) == candidateL.val {
+ // Found a long match, likely at least 8 bytes.
+ // Reference encoder checks all 8 bytes, we only check 4,
+ // but the likelihood of both the first 4 bytes and the hash matching should be enough.
+ t = candidateL.offset - e.cur
+ s += checkAt
+ if debugMatches {
+ println("long match (after short)")
+ }
+ break
+ }
+
+ t = candidateS.offset - e.cur
+ if debug && s <= t {
+ panic("s <= t")
+ }
+ if debug && s-t > e.maxMatchOff {
+ panic("s - t >e.maxMatchOff")
+ }
+ if debug && t < 0 {
+ panic("t<0")
+ }
+ if debugMatches {
+ println("short match")
+ }
+ break
+ }
+
+ // No match found, move forward in input.
+ s += stepSize + ((s - nextEmit) >> (kSearchStrength - 1))
+ if s >= sLimit {
+ break encodeLoop
+ }
+ cv = load6432(src, s)
+ }
+
+ // A 4-byte match has been found. Update recent offsets.
+ // We'll later see if more than 4 bytes.
+ offset2 = offset1
+ offset1 = s - t
+
+ if debug && s <= t {
+ panic("s <= t")
+ }
+
+ // Extend the 4-byte match as long as possible.
+ //l := e.matchlen(s+4, t+4, src) + 4
+ l := int32(matchLen(src[s+4:], src[t+4:])) + 4
+
+ // Extend backwards
+ tMin := s - e.maxMatchOff
+ if tMin < 0 {
+ tMin = 0
+ }
+ for t > tMin && s > nextEmit && src[t-1] == src[s-1] {
+ s--
+ t--
+ l++
+ }
+
+ // Write our sequence
+ var seq seq
+ seq.litLen = uint32(s - nextEmit)
+ seq.matchLen = uint32(l - zstdMinMatch)
+ if seq.litLen > 0 {
+ blk.literals = append(blk.literals, src[nextEmit:s]...)
+ }
+ seq.offset = uint32(s-t) + 3
+ s += l
+ if debugSequences {
+ println("sequence", seq, "next s:", s)
+ }
+ blk.sequences = append(blk.sequences, seq)
+ nextEmit = s
+ if s >= sLimit {
+ break encodeLoop
+ }
+
+ // Index match start+1 (long) and start+2 (short)
+ index0 := s - l + 1
+ // Index match end-2 (long) and end-1 (short)
+ index1 := s - 2
+
+ cv0 := load6432(src, index0)
+ cv1 := load6432(src, index1)
+ te0 := tableEntry{offset: index0 + e.cur, val: uint32(cv0)}
+ te1 := tableEntry{offset: index1 + e.cur, val: uint32(cv1)}
+ e.longTable[hash8(cv0, dFastLongTableBits)] = te0
+ e.longTable[hash8(cv1, dFastLongTableBits)] = te1
+ cv0 >>= 8
+ cv1 >>= 8
+ te0.offset++
+ te1.offset++
+ te0.val = uint32(cv0)
+ te1.val = uint32(cv1)
+ e.table[hash5(cv0, dFastShortTableBits)] = te0
+ e.table[hash5(cv1, dFastShortTableBits)] = te1
+
+ cv = load6432(src, s)
+
+ if len(blk.sequences) <= 2 {
+ continue
+ }
+
+ // Check offset 2
+ for {
+ o2 := s - offset2
+ if load3232(src, o2) != uint32(cv) {
+ // Do regular search
+ break
+ }
+
+ // Store this, since we have it.
+ nextHashS := hash5(cv1>>8, dFastShortTableBits)
+ nextHashL := hash8(cv, dFastLongTableBits)
+
+ // We have at least 4 byte match.
+ // No need to check backwards. We come straight from a match
+ //l := 4 + e.matchlen(s+4, o2+4, src)
+ l := 4 + int32(matchLen(src[s+4:], src[o2+4:]))
+
+ entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
+ e.longTable[nextHashL] = entry
+ e.table[nextHashS] = entry
+ seq.matchLen = uint32(l) - zstdMinMatch
+ seq.litLen = 0
+
+ // Since litlen is always 0, this is offset 1.
+ seq.offset = 1
+ s += l
+ nextEmit = s
+ if debugSequences {
+ println("sequence", seq, "next s:", s)
+ }
+ blk.sequences = append(blk.sequences, seq)
+
+ // Swap offset 1 and 2.
+ offset1, offset2 = offset2, offset1
+ if s >= sLimit {
+ // Finished
+ break encodeLoop
+ }
+ cv = load6432(src, s)
+ }
+ }
+
+ if int(nextEmit) < len(src) {
+ blk.literals = append(blk.literals, src[nextEmit:]...)
+ blk.extraLits = len(src) - int(nextEmit)
+ }
+ if debug {
+ println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
+ }
+
+}
diff --git a/vendor/github.com/klauspost/compress/zstd/enc_fast.go b/vendor/github.com/klauspost/compress/zstd/enc_fast.go
index 6f388de04..0bdddac5b 100644
--- a/vendor/github.com/klauspost/compress/zstd/enc_fast.go
+++ b/vendor/github.com/klauspost/compress/zstd/enc_fast.go
@@ -329,6 +329,246 @@ encodeLoop:
}
}
+// EncodeNoHist will encode a block with no history and no following blocks.
+// Most notable difference is that src will not be copied for history and
+// we do not need to check for max match length.
+func (e *fastEncoder) EncodeNoHist(blk *blockEnc, src []byte) {
+ const (
+ inputMargin = 8
+ minNonLiteralBlockSize = 1 + 1 + inputMargin
+ )
+ if debug {
+ if len(src) > maxBlockSize {
+ panic("src too big")
+ }
+ }
+ // Protect against e.cur wraparound.
+ if e.cur > (1<<30)+e.maxMatchOff {
+ for i := range e.table[:] {
+ e.table[i] = tableEntry{}
+ }
+ e.cur = e.maxMatchOff
+ }
+
+ s := int32(0)
+ blk.size = len(src)
+ if len(src) < minNonLiteralBlockSize {
+ blk.extraLits = len(src)
+ blk.literals = blk.literals[:len(src)]
+ copy(blk.literals, src)
+ return
+ }
+
+ sLimit := int32(len(src)) - inputMargin
+ // stepSize is the number of bytes to skip on every main loop iteration.
+ // It should be >= 2.
+ const stepSize = 2
+
+ // TEMPLATE
+ const hashLog = tableBits
+ // seems global, but would be nice to tweak.
+ const kSearchStrength = 8
+
+ // nextEmit is where in src the next emitLiteral should start from.
+ nextEmit := s
+ cv := load6432(src, s)
+
+ // Relative offsets
+ offset1 := int32(blk.recentOffsets[0])
+ offset2 := int32(blk.recentOffsets[1])
+
+ addLiterals := func(s *seq, until int32) {
+ if until == nextEmit {
+ return
+ }
+ blk.literals = append(blk.literals, src[nextEmit:until]...)
+ s.litLen = uint32(until - nextEmit)
+ }
+ if debug {
+ println("recent offsets:", blk.recentOffsets)
+ }
+
+encodeLoop:
+ for {
+ // t will contain the match offset when we find one.
+ // When existing the search loop, we have already checked 4 bytes.
+ var t int32
+
+ // We will not use repeat offsets across blocks.
+ // By not using them for the first 3 matches
+
+ for {
+ nextHash := hash6(cv, hashLog)
+ nextHash2 := hash6(cv>>8, hashLog)
+ candidate := e.table[nextHash]
+ candidate2 := e.table[nextHash2]
+ repIndex := s - offset1 + 2
+
+ e.table[nextHash] = tableEntry{offset: s + e.cur, val: uint32(cv)}
+ e.table[nextHash2] = tableEntry{offset: s + e.cur + 1, val: uint32(cv >> 8)}
+
+ if len(blk.sequences) > 2 && load3232(src, repIndex) == uint32(cv>>16) {
+ // Consider history as well.
+ var seq seq
+ // lenght := 4 + e.matchlen(s+6, repIndex+4, src)
+ lenght := 4 + int32(matchLen(src[s+6:], src[repIndex+4:]))
+
+ seq.matchLen = uint32(lenght - zstdMinMatch)
+
+ // We might be able to match backwards.
+ // Extend as long as we can.
+ start := s + 2
+ // We end the search early, so we don't risk 0 literals
+ // and have to do special offset treatment.
+ startLimit := nextEmit + 1
+
+ sMin := s - e.maxMatchOff
+ if sMin < 0 {
+ sMin = 0
+ }
+ for repIndex > sMin && start > startLimit && src[repIndex-1] == src[start-1] {
+ repIndex--
+ start--
+ seq.matchLen++
+ }
+ addLiterals(&seq, start)
+
+ // rep 0
+ seq.offset = 1
+ if debugSequences {
+ println("repeat sequence", seq, "next s:", s)
+ }
+ blk.sequences = append(blk.sequences, seq)
+ s += lenght + 2
+ nextEmit = s
+ if s >= sLimit {
+ if debug {
+ println("repeat ended", s, lenght)
+
+ }
+ break encodeLoop
+ }
+ cv = load6432(src, s)
+ continue
+ }
+ coffset0 := s - (candidate.offset - e.cur)
+ coffset1 := s - (candidate2.offset - e.cur) + 1
+ if coffset0 < e.maxMatchOff && uint32(cv) == candidate.val {
+ // found a regular match
+ t = candidate.offset - e.cur
+ if debug && s <= t {
+ panic("s <= t")
+ }
+ if debug && s-t > e.maxMatchOff {
+ panic("s - t >e.maxMatchOff")
+ }
+ break
+ }
+
+ if coffset1 < e.maxMatchOff && uint32(cv>>8) == candidate2.val {
+ // found a regular match
+ t = candidate2.offset - e.cur
+ s++
+ if debug && s <= t {
+ panic("s <= t")
+ }
+ if debug && s-t > e.maxMatchOff {
+ panic("s - t >e.maxMatchOff")
+ }
+ if debug && t < 0 {
+ panic("t<0")
+ }
+ break
+ }
+ s += stepSize + ((s - nextEmit) >> (kSearchStrength - 1))
+ if s >= sLimit {
+ break encodeLoop
+ }
+ cv = load6432(src, s)
+ }
+ // A 4-byte match has been found. We'll later see if more than 4 bytes.
+ offset2 = offset1
+ offset1 = s - t
+
+ if debug && s <= t {
+ panic("s <= t")
+ }
+
+ // Extend the 4-byte match as long as possible.
+ //l := e.matchlenNoHist(s+4, t+4, src) + 4
+ l := int32(matchLen(src[s+4:], src[t+4:])) + 4
+
+ // Extend backwards
+ tMin := s - e.maxMatchOff
+ if tMin < 0 {
+ tMin = 0
+ }
+ for t > tMin && s > nextEmit && src[t-1] == src[s-1] {
+ s--
+ t--
+ l++
+ }
+
+ // Write our sequence.
+ var seq seq
+ seq.litLen = uint32(s - nextEmit)
+ seq.matchLen = uint32(l - zstdMinMatch)
+ if seq.litLen > 0 {
+ blk.literals = append(blk.literals, src[nextEmit:s]...)
+ }
+ // Don't use repeat offsets
+ seq.offset = uint32(s-t) + 3
+ s += l
+ if debugSequences {
+ println("sequence", seq, "next s:", s)
+ }
+ blk.sequences = append(blk.sequences, seq)
+ nextEmit = s
+ if s >= sLimit {
+ break encodeLoop
+ }
+ cv = load6432(src, s)
+
+ // Check offset 2
+ if o2 := s - offset2; len(blk.sequences) > 2 && load3232(src, o2) == uint32(cv) {
+ // We have at least 4 byte match.
+ // No need to check backwards. We come straight from a match
+ //l := 4 + e.matchlenNoHist(s+4, o2+4, src)
+ l := 4 + int32(matchLen(src[s+4:], src[o2+4:]))
+
+ // Store this, since we have it.
+ nextHash := hash6(cv, hashLog)
+ e.table[nextHash] = tableEntry{offset: s + e.cur, val: uint32(cv)}
+ seq.matchLen = uint32(l) - zstdMinMatch
+ seq.litLen = 0
+ // Since litlen is always 0, this is offset 1.
+ seq.offset = 1
+ s += l
+ nextEmit = s
+ if debugSequences {
+ println("sequence", seq, "next s:", s)
+ }
+ blk.sequences = append(blk.sequences, seq)
+
+ // Swap offset 1 and 2.
+ offset1, offset2 = offset2, offset1
+ if s >= sLimit {
+ break encodeLoop
+ }
+ // Prepare next loop.
+ cv = load6432(src, s)
+ }
+ }
+
+ if int(nextEmit) < len(src) {
+ blk.literals = append(blk.literals, src[nextEmit:]...)
+ blk.extraLits = len(src) - int(nextEmit)
+ }
+ if debug {
+ println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
+ }
+}
+
func (e *fastEncoder) addBlock(src []byte) int32 {
// check if we have space already
if len(e.hist)+len(src) > cap(e.hist) {
@@ -362,6 +602,11 @@ func (e *fastEncoder) UseBlock(enc *blockEnc) {
e.blk = enc
}
+func (e *fastEncoder) matchlenNoHist(s, t int32, src []byte) int32 {
+ // Extend the match to be as long as possible.
+ return int32(matchLen(src[s:], src[t:]))
+}
+
func (e *fastEncoder) matchlen(s, t int32, src []byte) int32 {
if debug {
if s < 0 {
diff --git a/vendor/github.com/klauspost/compress/zstd/encoder.go b/vendor/github.com/klauspost/compress/zstd/encoder.go
index f413042f4..366dd66bd 100644
--- a/vendor/github.com/klauspost/compress/zstd/encoder.go
+++ b/vendor/github.com/klauspost/compress/zstd/encoder.go
@@ -29,6 +29,7 @@ type Encoder struct {
type encoder interface {
Encode(blk *blockEnc, src []byte)
+ EncodeNoHist(blk *blockEnc, src []byte)
Block() *blockEnc
CRC() *xxhash.Digest
AppendCRC([]byte) []byte
@@ -433,7 +434,8 @@ func (e *Encoder) EncodeAll(src, dst []byte) []byte {
}()
enc.Reset()
blk := enc.Block()
- single := len(src) > 1<<20
+ // Use single segments when above minimum window and below 1MB.
+ single := len(src) < 1<<20 && len(src) > MinWindowSize
if e.o.single != nil {
single = *e.o.single
}
@@ -454,25 +456,22 @@ func (e *Encoder) EncodeAll(src, dst []byte) []byte {
panic(err)
}
- for len(src) > 0 {
- todo := src
- if len(todo) > e.o.blockSize {
- todo = todo[:e.o.blockSize]
- }
- src = src[len(todo):]
+ if len(src) <= e.o.blockSize && len(src) <= maxBlockSize {
+ // Slightly faster with no history and everything in one block.
if e.o.crc {
- _, _ = enc.CRC().Write(todo)
+ _, _ = enc.CRC().Write(src)
}
blk.reset(nil)
- blk.pushOffsets()
- enc.Encode(blk, todo)
- if len(src) == 0 {
- blk.last = true
- }
- err := errIncompressible
+ blk.last = true
+ enc.EncodeNoHist(blk, src)
+
// If we got the exact same number of literals as input,
// assume the literals cannot be compressed.
- if len(blk.literals) != len(todo) || len(todo) != e.o.blockSize {
+ err := errIncompressible
+ oldout := blk.output
+ if len(blk.literals) != len(src) || len(src) != e.o.blockSize {
+ // Output directly to dst
+ blk.output = dst
err = blk.encode(e.o.noEntropy)
}
@@ -481,13 +480,49 @@ func (e *Encoder) EncodeAll(src, dst []byte) []byte {
if debug {
println("Storing incompressible block as raw")
}
- blk.encodeRaw(todo)
- blk.popOffsets()
+ dst = blk.encodeRawTo(dst, src)
case nil:
+ dst = blk.output
default:
panic(err)
}
- dst = append(dst, blk.output...)
+ blk.output = oldout
+ } else {
+ for len(src) > 0 {
+ todo := src
+ if len(todo) > e.o.blockSize {
+ todo = todo[:e.o.blockSize]
+ }
+ src = src[len(todo):]
+ if e.o.crc {
+ _, _ = enc.CRC().Write(todo)
+ }
+ blk.reset(nil)
+ blk.pushOffsets()
+ enc.Encode(blk, todo)
+ if len(src) == 0 {
+ blk.last = true
+ }
+ err := errIncompressible
+ // If we got the exact same number of literals as input,
+ // assume the literals cannot be compressed.
+ if len(blk.literals) != len(todo) || len(todo) != e.o.blockSize {
+ err = blk.encode(e.o.noEntropy)
+ }
+
+ switch err {
+ case errIncompressible:
+ if debug {
+ println("Storing incompressible block as raw")
+ }
+ dst = blk.encodeRawTo(dst, todo)
+ blk.popOffsets()
+ case nil:
+ dst = append(dst, blk.output...)
+ default:
+ panic(err)
+ }
+ }
}
if e.o.crc {
dst = enc.AppendCRC(dst)