build(deps): bump github.com/containers/storage from 1.13.5 to 1.14.0

Bumps [github.com/containers/storage](https://github.com/containers/storage) from 1.13.5 to 1.14.0.
- [Release notes](https://github.com/containers/storage/releases)
- [Changelog](https://github.com/containers/storage/blob/master/docs/containers-storage-changes.md)
- [Commits](https://github.com/containers/storage/compare/v1.13.5...v1.14.0)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

34 files changed, 2934 insertions, 2186 deletions

diff --git a/vendor/github.com/klauspost/compress/flate/crc32_amd64.go b/vendor/github.com/klauspost/compress/flate/crc32_amd64.go
deleted file mode 100644
index 8298d309a..000000000
--- a/vendor/github.com/klauspost/compress/flate/crc32_amd64.go
+++ /dev/null
@@ -1,42 +0,0 @@
-//+build !noasm
-//+build !appengine
-//+build !gccgo
-
-// Copyright 2015, Klaus Post, see LICENSE for details.
-
-package flate
-
-import (
-	"github.com/klauspost/cpuid"
-)
-
-// crc32sse returns a hash for the first 4 bytes of the slice
-// len(a) must be >= 4.
-//go:noescape
-func crc32sse(a []byte) uint32
-
-// crc32sseAll calculates hashes for each 4-byte set in a.
-// dst must be east len(a) - 4 in size.
-// The size is not checked by the assembly.
-//go:noescape
-func crc32sseAll(a []byte, dst []uint32)
-
-// matchLenSSE4 returns the number of matching bytes in a and b
-// up to length 'max'. Both slices must be at least 'max'
-// bytes in size.
-//
-// TODO: drop the "SSE4" name, since it doesn't use any SSE instructions.
-//
-//go:noescape
-func matchLenSSE4(a, b []byte, max int) int
-
-// histogram accumulates a histogram of b in h.
-// h must be at least 256 entries in length,
-// and must be cleared before calling this function.
-//go:noescape
-func histogram(b []byte, h []int32)
-
-// Detect SSE 4.2 feature.
-func init() {
-	useSSE42 = cpuid.CPU.SSE42()
-}
diff --git a/vendor/github.com/klauspost/compress/flate/crc32_amd64.s b/vendor/github.com/klauspost/compress/flate/crc32_amd64.s
deleted file mode 100644
index a79943727..000000000
--- a/vendor/github.com/klauspost/compress/flate/crc32_amd64.s
+++ /dev/null
@@ -1,214 +0,0 @@
-//+build !noasm
-//+build !appengine
-//+build !gccgo
-
-// Copyright 2015, Klaus Post, see LICENSE for details.
-
-// func crc32sse(a []byte) uint32
-TEXT ·crc32sse(SB), 4, $0
-	MOVQ a+0(FP), R10
-	XORQ BX, BX
-
-	// CRC32   dword (R10), EBX
-	BYTE $0xF2; BYTE $0x41; BYTE $0x0f
-	BYTE $0x38; BYTE $0xf1; BYTE $0x1a
-
-	MOVL BX, ret+24(FP)
-	RET
-
-// func crc32sseAll(a []byte, dst []uint32)
-TEXT ·crc32sseAll(SB), 4, $0
-	MOVQ  a+0(FP), R8      // R8: src
-	MOVQ  a_len+8(FP), R10 // input length
-	MOVQ  dst+24(FP), R9   // R9: dst
-	SUBQ  $4, R10
-	JS    end
-	JZ    one_crc
-	MOVQ  R10, R13
-	SHRQ  $2, R10          // len/4
-	ANDQ  $3, R13          // len&3
-	XORQ  BX, BX
-	ADDQ  $1, R13
-	TESTQ R10, R10
-	JZ    rem_loop
-
-crc_loop:
-	MOVQ (R8), R11
-	XORQ BX, BX
-	XORQ DX, DX
-	XORQ DI, DI
-	MOVQ R11, R12
-	SHRQ $8, R11
-	MOVQ R12, AX
-	MOVQ R11, CX
-	SHRQ $16, R12
-	SHRQ $16, R11
-	MOVQ R12, SI
-
-	// CRC32   EAX, EBX
-	BYTE $0xF2; BYTE $0x0f
-	BYTE $0x38; BYTE $0xf1; BYTE $0xd8
-
-	// CRC32   ECX, EDX
-	BYTE $0xF2; BYTE $0x0f
-	BYTE $0x38; BYTE $0xf1; BYTE $0xd1
-
-	// CRC32   ESI, EDI
-	BYTE $0xF2; BYTE $0x0f
-	BYTE $0x38; BYTE $0xf1; BYTE $0xfe
-	MOVL BX, (R9)
-	MOVL DX, 4(R9)
-	MOVL DI, 8(R9)
-
-	XORQ BX, BX
-	MOVL R11, AX
-
-	// CRC32   EAX, EBX
-	BYTE $0xF2; BYTE $0x0f
-	BYTE $0x38; BYTE $0xf1; BYTE $0xd8
-	MOVL BX, 12(R9)
-
-	ADDQ $16, R9
-	ADDQ $4, R8
-	XORQ BX, BX
-	SUBQ $1, R10
-	JNZ  crc_loop
-
-rem_loop:
-	MOVL (R8), AX
-
-	// CRC32   EAX, EBX
-	BYTE $0xF2; BYTE $0x0f
-	BYTE $0x38; BYTE $0xf1; BYTE $0xd8
-
-	MOVL BX, (R9)
-	ADDQ $4, R9
-	ADDQ $1, R8
-	XORQ BX, BX
-	SUBQ $1, R13
-	JNZ  rem_loop
-
-end:
-	RET
-
-one_crc:
-	MOVQ $1, R13
-	XORQ BX, BX
-	JMP  rem_loop
-
-// func matchLenSSE4(a, b []byte, max int) int
-TEXT ·matchLenSSE4(SB), 4, $0
-	MOVQ a_base+0(FP), SI
-	MOVQ b_base+24(FP), DI
-	MOVQ DI, DX
-	MOVQ max+48(FP), CX
-
-cmp8:
-	// As long as we are 8 or more bytes before the end of max, we can load and
-	// compare 8 bytes at a time. If those 8 bytes are equal, repeat.
-	CMPQ CX, $8
-	JLT  cmp1
-	MOVQ (SI), AX
-	MOVQ (DI), BX
-	CMPQ AX, BX
-	JNE  bsf
-	ADDQ $8, SI
-	ADDQ $8, DI
-	SUBQ $8, CX
-	JMP  cmp8
-
-bsf:
-	// If those 8 bytes were not equal, XOR the two 8 byte values, and return
-	// the index of the first byte that differs. The BSF instruction finds the
-	// least significant 1 bit, the amd64 architecture is little-endian, and
-	// the shift by 3 converts a bit index to a byte index.
-	XORQ AX, BX
-	BSFQ BX, BX
-	SHRQ $3, BX
-	ADDQ BX, DI
-
-	// Subtract off &b[0] to convert from &b[ret] to ret, and return.
-	SUBQ DX, DI
-	MOVQ DI, ret+56(FP)
-	RET
-
-cmp1:
-	// In the slices' tail, compare 1 byte at a time.
-	CMPQ CX, $0
-	JEQ  matchLenEnd
-	MOVB (SI), AX
-	MOVB (DI), BX
-	CMPB AX, BX
-	JNE  matchLenEnd
-	ADDQ $1, SI
-	ADDQ $1, DI
-	SUBQ $1, CX
-	JMP  cmp1
-
-matchLenEnd:
-	// Subtract off &b[0] to convert from &b[ret] to ret, and return.
-	SUBQ DX, DI
-	MOVQ DI, ret+56(FP)
-	RET
-
-// func histogram(b []byte, h []int32)
-TEXT ·histogram(SB), 4, $0
-	MOVQ b+0(FP), SI     // SI: &b
-	MOVQ b_len+8(FP), R9 // R9: len(b)
-	MOVQ h+24(FP), DI    // DI: Histogram
-	MOVQ R9, R8
-	SHRQ $3, R8
-	JZ   hist1
-	XORQ R11, R11
-
-loop_hist8:
-	MOVQ (SI), R10
-
-	MOVB R10, R11
-	INCL (DI)(R11*4)
-	SHRQ $8, R10
-
-	MOVB R10, R11
-	INCL (DI)(R11*4)
-	SHRQ $8, R10
-
-	MOVB R10, R11
-	INCL (DI)(R11*4)
-	SHRQ $8, R10
-
-	MOVB R10, R11
-	INCL (DI)(R11*4)
-	SHRQ $8, R10
-
-	MOVB R10, R11
-	INCL (DI)(R11*4)
-	SHRQ $8, R10
-
-	MOVB R10, R11
-	INCL (DI)(R11*4)
-	SHRQ $8, R10
-
-	MOVB R10, R11
-	INCL (DI)(R11*4)
-	SHRQ $8, R10
-
-	INCL (DI)(R10*4)
-
-	ADDQ $8, SI
-	DECQ R8
-	JNZ  loop_hist8
-
-hist1:
-	ANDQ $7, R9
-	JZ   end_hist
-	XORQ R10, R10
-
-loop_hist1:
-	MOVB (SI), R10
-	INCL (DI)(R10*4)
-	INCQ SI
-	DECQ R9
-	JNZ  loop_hist1
-
-end_hist:
-	RET
diff --git a/vendor/github.com/klauspost/compress/flate/crc32_noasm.go b/vendor/github.com/klauspost/compress/flate/crc32_noasm.go
deleted file mode 100644
index dcf43bd50..000000000
--- a/vendor/github.com/klauspost/compress/flate/crc32_noasm.go
+++ /dev/null
@@ -1,35 +0,0 @@
-//+build !amd64 noasm appengine gccgo
-
-// Copyright 2015, Klaus Post, see LICENSE for details.
-
-package flate
-
-func init() {
-	useSSE42 = false
-}
-
-// crc32sse should never be called.
-func crc32sse(a []byte) uint32 {
-	panic("no assembler")
-}
-
-// crc32sseAll should never be called.
-func crc32sseAll(a []byte, dst []uint32) {
-	panic("no assembler")
-}
-
-// matchLenSSE4 should never be called.
-func matchLenSSE4(a, b []byte, max int) int {
-	panic("no assembler")
-	return 0
-}
-
-// histogram accumulates a histogram of b in h.
-//
-// len(h) must be >= 256, and h's elements must be all zeroes.
-func histogram(b []byte, h []int32) {
-	h = h[:256]
-	for _, t := range b {
-		h[t]++
-	}
-}
diff --git a/vendor/github.com/klauspost/compress/flate/deflate.go b/vendor/github.com/klauspost/compress/flate/deflate.go
index 628795120..20c94f596 100644
--- a/vendor/github.com/klauspost/compress/flate/deflate.go
+++ b/vendor/github.com/klauspost/compress/flate/deflate.go
@@ -50,8 +50,6 @@ const (
 	skipNever = math.MaxInt32
 )
 
-var useSSE42 bool
-
 type compressionLevel struct {
 	good, lazy, nice, chain, fastSkipHashing, level int
 }
@@ -97,9 +95,8 @@ type advancedState struct {
 	hashOffset int
 
 	// input window: unprocessed data is window[index:windowEnd]
-	index      int
-	bulkHasher func([]byte, []uint32)
-	hashMatch  [maxMatchLength + minMatchLength]uint32
+	index     int
+	hashMatch [maxMatchLength + minMatchLength]uint32
 }
 
 type compressor struct {
@@ -120,7 +117,7 @@ type compressor struct {
 
 	// queued output tokens
 	tokens tokens
-	snap   fastEnc
+	fast   fastEnc
 	state  *advancedState
 }
 
@@ -164,14 +161,14 @@ func (d *compressor) fillDeflate(b []byte) int {
 	return n
 }
 
-func (d *compressor) writeBlock(tok tokens, index int, eof bool) error {
+func (d *compressor) writeBlock(tok *tokens, index int, eof bool) error {
 	if index > 0 || eof {
 		var window []byte
 		if d.blockStart <= index {
 			window = d.window[d.blockStart:index]
 		}
 		d.blockStart = index
-		d.w.writeBlock(tok.tokens[:tok.n], eof, window)
+		d.w.writeBlock(tok, eof, window)
 		return d.w.err
 	}
 	return nil
@@ -180,20 +177,20 @@ func (d *compressor) writeBlock(tok tokens, index int, eof bool) error {
 // writeBlockSkip writes the current block and uses the number of tokens
 // to determine if the block should be stored on no matches, or
 // only huffman encoded.
-func (d *compressor) writeBlockSkip(tok tokens, index int, eof bool) error {
+func (d *compressor) writeBlockSkip(tok *tokens, index int, eof bool) error {
 	if index > 0 || eof {
 		if d.blockStart <= index {
 			window := d.window[d.blockStart:index]
 			// If we removed less than a 64th of all literals
 			// we huffman compress the block.
 			if int(tok.n) > len(window)-int(tok.n>>6) {
-				d.w.writeBlockHuff(eof, window)
+				d.w.writeBlockHuff(eof, window, d.sync)
 			} else {
 				// Write a dynamic huffman block.
-				d.w.writeBlockDynamic(tok.tokens[:tok.n], eof, window)
+				d.w.writeBlockDynamic(tok, eof, window, d.sync)
 			}
 		} else {
-			d.w.writeBlock(tok.tokens[:tok.n], eof, nil)
+			d.w.writeBlock(tok, eof, nil)
 		}
 		d.blockStart = index
 		return d.w.err
@@ -208,8 +205,16 @@ func (d *compressor) writeBlockSkip(tok tokens, index int, eof bool) error {
 func (d *compressor) fillWindow(b []byte) {
 	// Do not fill window if we are in store-only mode,
 	// use constant or Snappy compression.
-	switch d.compressionLevel.level {
-	case 0, 1, 2:
+	if d.level == 0 {
+		return
+	}
+	if d.fast != nil {
+		// encode the last data, but discard the result
+		if len(b) > maxMatchOffset {
+			b = b[len(b)-maxMatchOffset:]
+		}
+		d.fast.Encode(&d.tokens, b)
+		d.tokens.Reset()
 		return
 	}
 	s := d.state
@@ -236,7 +241,7 @@ func (d *compressor) fillWindow(b []byte) {
 		}
 
 		dst := s.hashMatch[:dstSize]
-		s.bulkHasher(tocheck, dst)
+		bulkHash4(tocheck, dst)
 		var newH uint32
 		for i, val := range dst {
 			di := i + startindex
@@ -284,62 +289,7 @@ func (d *compressor) findMatch(pos int, prevHead int, prevLength int, lookahead
 
 	for i := prevHead; tries > 0; tries-- {
 		if wEnd == win[i+length] {
-			n := matchLen(win[i:], wPos, minMatchLook)
-
-			if n > length && (n > minMatchLength || pos-i <= 4096) {
-				length = n
-				offset = pos - i
-				ok = true
-				if n >= nice {
-					// The match is good enough that we don't try to find a better one.
-					break
-				}
-				wEnd = win[pos+n]
-			}
-		}
-		if i == minIndex {
-			// hashPrev[i & windowMask] has already been overwritten, so stop now.
-			break
-		}
-		i = int(d.state.hashPrev[i&windowMask]) - d.state.hashOffset
-		if i < minIndex || i < 0 {
-			break
-		}
-	}
-	return
-}
-
-// Try to find a match starting at index whose length is greater than prevSize.
-// We only look at chainCount possibilities before giving up.
-// pos = s.index, prevHead = s.chainHead-s.hashOffset, prevLength=minMatchLength-1, lookahead
-func (d *compressor) findMatchSSE(pos int, prevHead int, prevLength int, lookahead int) (length, offset int, ok bool) {
-	minMatchLook := maxMatchLength
-	if lookahead < minMatchLook {
-		minMatchLook = lookahead
-	}
-
-	win := d.window[0 : pos+minMatchLook]
-
-	// We quit when we get a match that's at least nice long
-	nice := len(win) - pos
-	if d.nice < nice {
-		nice = d.nice
-	}
-
-	// If we've got a match that's good enough, only look in 1/4 the chain.
-	tries := d.chain
-	length = prevLength
-	if length >= d.good {
-		tries >>= 2
-	}
-
-	wEnd := win[pos+length]
-	wPos := win[pos:]
-	minIndex := pos - windowSize
-
-	for i := prevHead; tries > 0; tries-- {
-		if wEnd == win[i+length] {
-			n := matchLenSSE4(win[i:], wPos, minMatchLook)
+			n := matchLen(win[i:i+minMatchLook], wPos)
 
 			if n > length && (n > minMatchLength || pos-i <= 4096) {
 				length = n
@@ -372,42 +322,27 @@ func (d *compressor) writeStoredBlock(buf []byte) error {
 	return d.w.err
 }
 
-const hashmul = 0x1e35a7bd
-
 // hash4 returns a hash representation of the first 4 bytes
 // of the supplied slice.
 // The caller must ensure that len(b) >= 4.
 func hash4(b []byte) uint32 {
-	return ((uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24) * hashmul) >> (32 - hashBits)
+	b = b[:4]
+	return hash4u(uint32(b[3])|uint32(b[2])<<8|uint32(b[1])<<16|uint32(b[0])<<24, hashBits)
 }
 
 // bulkHash4 will compute hashes using the same
 // algorithm as hash4
 func bulkHash4(b []byte, dst []uint32) {
-	if len(b) < minMatchLength {
+	if len(b) < 4 {
 		return
 	}
 	hb := uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
-	dst[0] = (hb * hashmul) >> (32 - hashBits)
-	end := len(b) - minMatchLength + 1
+	dst[0] = hash4u(hb, hashBits)
+	end := len(b) - 4 + 1
 	for i := 1; i < end; i++ {
 		hb = (hb << 8) | uint32(b[i+3])
-		dst[i] = (hb * hashmul) >> (32 - hashBits)
-	}
-}
-
-// matchLen returns the number of matching bytes in a and b
-// up to length 'max'. Both slices must be at least 'max'
-// bytes in size.
-func matchLen(a, b []byte, max int) int {
-	a = a[:max]
-	b = b[:len(a)]
-	for i, av := range a {
-		if b[i] != av {
-			return i
-		}
+		dst[i] = hash4u(hb, hashBits)
 	}
-	return max
 }
 
 func (d *compressor) initDeflate() {
@@ -424,149 +359,6 @@ func (d *compressor) initDeflate() {
 	s.offset = 0
 	s.hash = 0
 	s.chainHead = -1
-	s.bulkHasher = bulkHash4
-	if useSSE42 {
-		s.bulkHasher = crc32sseAll
-	}
-}
-
-// Assumes that d.fastSkipHashing != skipNever,
-// otherwise use deflateLazy
-func (d *compressor) deflate() {
-	s := d.state
-	// Sanity enables additional runtime tests.
-	// It's intended to be used during development
-	// to supplement the currently ad-hoc unit tests.
-	const sanity = false
-
-	if d.windowEnd-s.index < minMatchLength+maxMatchLength && !d.sync {
-		return
-	}
-
-	s.maxInsertIndex = d.windowEnd - (minMatchLength - 1)
-	if s.index < s.maxInsertIndex {
-		s.hash = hash4(d.window[s.index : s.index+minMatchLength])
-	}
-
-	for {
-		if sanity && s.index > d.windowEnd {
-			panic("index > windowEnd")
-		}
-		lookahead := d.windowEnd - s.index
-		if lookahead < minMatchLength+maxMatchLength {
-			if !d.sync {
-				return
-			}
-			if sanity && s.index > d.windowEnd {
-				panic("index > windowEnd")
-			}
-			if lookahead == 0 {
-				if d.tokens.n > 0 {
-					if d.err = d.writeBlockSkip(d.tokens, s.index, false); d.err != nil {
-						return
-					}
-					d.tokens.n = 0
-				}
-				return
-			}
-		}
-		if s.index < s.maxInsertIndex {
-			// Update the hash
-			s.hash = hash4(d.window[s.index : s.index+minMatchLength])
-			ch := s.hashHead[s.hash&hashMask]
-			s.chainHead = int(ch)
-			s.hashPrev[s.index&windowMask] = ch
-			s.hashHead[s.hash&hashMask] = uint32(s.index + s.hashOffset)
-		}
-		s.length = minMatchLength - 1
-		s.offset = 0
-		minIndex := s.index - windowSize
-		if minIndex < 0 {
-			minIndex = 0
-		}
-
-		if s.chainHead-s.hashOffset >= minIndex && lookahead > minMatchLength-1 {
-			if newLength, newOffset, ok := d.findMatch(s.index, s.chainHead-s.hashOffset, minMatchLength-1, lookahead); ok {
-				s.length = newLength
-				s.offset = newOffset
-			}
-		}
-		if s.length >= minMatchLength {
-			s.ii = 0
-			// There was a match at the previous step, and the current match is
-			// not better. Output the previous match.
-			// "s.length-3" should NOT be "s.length-minMatchLength", since the format always assume 3
-			d.tokens.tokens[d.tokens.n] = matchToken(uint32(s.length-3), uint32(s.offset-minOffsetSize))
-			d.tokens.n++
-			// Insert in the hash table all strings up to the end of the match.
-			// index and index-1 are already inserted. If there is not enough
-			// lookahead, the last two strings are not inserted into the hash
-			// table.
-			if s.length <= d.fastSkipHashing {
-				var newIndex int
-				newIndex = s.index + s.length
-				// Calculate missing hashes
-				end := newIndex
-				if end > s.maxInsertIndex {
-					end = s.maxInsertIndex
-				}
-				end += minMatchLength - 1
-				startindex := s.index + 1
-				if startindex > s.maxInsertIndex {
-					startindex = s.maxInsertIndex
-				}
-				tocheck := d.window[startindex:end]
-				dstSize := len(tocheck) - minMatchLength + 1
-				if dstSize > 0 {
-					dst := s.hashMatch[:dstSize]
-					bulkHash4(tocheck, dst)
-					var newH uint32
-					for i, val := range dst {
-						di := i + startindex
-						newH = val & hashMask
-						// Get previous value with the same hash.
-						// Our chain should point to the previous value.
-						s.hashPrev[di&windowMask] = s.hashHead[newH]
-						// Set the head of the hash chain to us.
-						s.hashHead[newH] = uint32(di + s.hashOffset)
-					}
-					s.hash = newH
-				}
-				s.index = newIndex
-			} else {
-				// For matches this long, we don't bother inserting each individual
-				// item into the table.
-				s.index += s.length
-				if s.index < s.maxInsertIndex {
-					s.hash = hash4(d.window[s.index : s.index+minMatchLength])
-				}
-			}
-			if d.tokens.n == maxFlateBlockTokens {
-				// The block includes the current character
-				if d.err = d.writeBlockSkip(d.tokens, s.index, false); d.err != nil {
-					return
-				}
-				d.tokens.n = 0
-			}
-		} else {
-			s.ii++
-			end := s.index + int(s.ii>>uint(d.fastSkipHashing)) + 1
-			if end > d.windowEnd {
-				end = d.windowEnd
-			}
-			for i := s.index; i < end; i++ {
-				d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[i]))
-				d.tokens.n++
-				if d.tokens.n == maxFlateBlockTokens {
-					if d.err = d.writeBlockSkip(d.tokens, i+1, false); d.err != nil {
-						return
-					}
-					d.tokens.n = 0
-				}
-			}
-			s.index = end
-		}
-	}
 }
 
 // deflateLazy is the same as deflate, but with d.fastSkipHashing == skipNever,
@@ -603,15 +395,14 @@ func (d *compressor) deflateLazy() {
 				// Flush current output block if any.
 				if d.byteAvailable {
 					// There is still one pending token that needs to be flushed
-					d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-					d.tokens.n++
+					d.tokens.AddLiteral(d.window[s.index-1])
 					d.byteAvailable = false
 				}
 				if d.tokens.n > 0 {
-					if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
+					if d.err = d.writeBlock(&d.tokens, s.index, false); d.err != nil {
 						return
 					}
-					d.tokens.n = 0
+					d.tokens.Reset()
 				}
 				return
 			}
@@ -642,8 +433,7 @@ func (d *compressor) deflateLazy() {
 		if prevLength >= minMatchLength && s.length <= prevLength {
 			// There was a match at the previous step, and the current match is
 			// not better. Output the previous match.
-			d.tokens.tokens[d.tokens.n] = matchToken(uint32(prevLength-3), uint32(prevOffset-minOffsetSize))
-			d.tokens.n++
+			d.tokens.AddMatch(uint32(prevLength-3), uint32(prevOffset-minOffsetSize))
 
 			// Insert in the hash table all strings up to the end of the match.
 			// index and index-1 are already inserted. If there is not enough
@@ -684,10 +474,10 @@ func (d *compressor) deflateLazy() {
 			s.length = minMatchLength - 1
 			if d.tokens.n == maxFlateBlockTokens {
 				// The block includes the current character
-				if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
+				if d.err = d.writeBlock(&d.tokens, s.index, false); d.err != nil {
 					return
 				}
-				d.tokens.n = 0
+				d.tokens.Reset()
 			}
 		} else {
 			// Reset, if we got a match this run.
@@ -697,13 +487,12 @@ func (d *compressor) deflateLazy() {
 			// We have a byte waiting. Emit it.
 			if d.byteAvailable {
 				s.ii++
-				d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-				d.tokens.n++
+				d.tokens.AddLiteral(d.window[s.index-1])
 				if d.tokens.n == maxFlateBlockTokens {
-					if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
+					if d.err = d.writeBlock(&d.tokens, s.index, false); d.err != nil {
 						return
 					}
-					d.tokens.n = 0
+					d.tokens.Reset()
 				}
 				s.index++
 
@@ -716,343 +505,24 @@ func (d *compressor) deflateLazy() {
 							break
 						}
 
-						d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-						d.tokens.n++
+						d.tokens.AddLiteral(d.window[s.index-1])
 						if d.tokens.n == maxFlateBlockTokens {
-							if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
+							if d.err = d.writeBlock(&d.tokens, s.index, false); d.err != nil {
 								return
 							}
-							d.tokens.n = 0
+							d.tokens.Reset()
 						}
 						s.index++
 					}
 					// Flush last byte
-					d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-					d.tokens.n++
+					d.tokens.AddLiteral(d.window[s.index-1])
 					d.byteAvailable = false
 					// s.length = minMatchLength - 1 // not needed, since s.ii is reset above, so it should never be > minMatchLength
 					if d.tokens.n == maxFlateBlockTokens {
-						if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
+						if d.err = d.writeBlock(&d.tokens, s.index, false); d.err != nil {
 							return
 						}
-						d.tokens.n = 0
-					}
-				}
-			} else {
-				s.index++
-				d.byteAvailable = true
-			}
-		}
-	}
-}
-
-// Assumes that d.fastSkipHashing != skipNever,
-// otherwise use deflateLazySSE
-func (d *compressor) deflateSSE() {
-	s := d.state
-	// Sanity enables additional runtime tests.
-	// It's intended to be used during development
-	// to supplement the currently ad-hoc unit tests.
-	const sanity = false
-
-	if d.windowEnd-s.index < minMatchLength+maxMatchLength && !d.sync {
-		return
-	}
-
-	s.maxInsertIndex = d.windowEnd - (minMatchLength - 1)
-	if s.index < s.maxInsertIndex {
-		s.hash = crc32sse(d.window[s.index:s.index+minMatchLength]) & hashMask
-	}
-
-	for {
-		if sanity && s.index > d.windowEnd {
-			panic("index > windowEnd")
-		}
-		lookahead := d.windowEnd - s.index
-		if lookahead < minMatchLength+maxMatchLength {
-			if !d.sync {
-				return
-			}
-			if sanity && s.index > d.windowEnd {
-				panic("index > windowEnd")
-			}
-			if lookahead == 0 {
-				if d.tokens.n > 0 {
-					if d.err = d.writeBlockSkip(d.tokens, s.index, false); d.err != nil {
-						return
-					}
-					d.tokens.n = 0
-				}
-				return
-			}
-		}
-		if s.index < s.maxInsertIndex {
-			// Update the hash
-			s.hash = crc32sse(d.window[s.index:s.index+minMatchLength]) & hashMask
-			ch := s.hashHead[s.hash]
-			s.chainHead = int(ch)
-			s.hashPrev[s.index&windowMask] = ch
-			s.hashHead[s.hash] = uint32(s.index + s.hashOffset)
-		}
-		s.length = minMatchLength - 1
-		s.offset = 0
-		minIndex := s.index - windowSize
-		if minIndex < 0 {
-			minIndex = 0
-		}
-
-		if s.chainHead-s.hashOffset >= minIndex && lookahead > minMatchLength-1 {
-			if newLength, newOffset, ok := d.findMatchSSE(s.index, s.chainHead-s.hashOffset, minMatchLength-1, lookahead); ok {
-				s.length = newLength
-				s.offset = newOffset
-			}
-		}
-		if s.length >= minMatchLength {
-			s.ii = 0
-			// There was a match at the previous step, and the current match is
-			// not better. Output the previous match.
-			// "s.length-3" should NOT be "s.length-minMatchLength", since the format always assume 3
-			d.tokens.tokens[d.tokens.n] = matchToken(uint32(s.length-3), uint32(s.offset-minOffsetSize))
-			d.tokens.n++
-			// Insert in the hash table all strings up to the end of the match.
-			// index and index-1 are already inserted. If there is not enough
-			// lookahead, the last two strings are not inserted into the hash
-			// table.
-			if s.length <= d.fastSkipHashing {
-				var newIndex int
-				newIndex = s.index + s.length
-				// Calculate missing hashes
-				end := newIndex
-				if end > s.maxInsertIndex {
-					end = s.maxInsertIndex
-				}
-				end += minMatchLength - 1
-				startindex := s.index + 1
-				if startindex > s.maxInsertIndex {
-					startindex = s.maxInsertIndex
-				}
-				tocheck := d.window[startindex:end]
-				dstSize := len(tocheck) - minMatchLength + 1
-				if dstSize > 0 {
-					dst := s.hashMatch[:dstSize]
-
-					crc32sseAll(tocheck, dst)
-					var newH uint32
-					for i, val := range dst {
-						di := i + startindex
-						newH = val & hashMask
-						// Get previous value with the same hash.
-						// Our chain should point to the previous value.
-						s.hashPrev[di&windowMask] = s.hashHead[newH]
-						// Set the head of the hash chain to us.
-						s.hashHead[newH] = uint32(di + s.hashOffset)
-					}
-					s.hash = newH
-				}
-				s.index = newIndex
-			} else {
-				// For matches this long, we don't bother inserting each individual
-				// item into the table.
-				s.index += s.length
-				if s.index < s.maxInsertIndex {
-					s.hash = crc32sse(d.window[s.index:s.index+minMatchLength]) & hashMask
-				}
-			}
-			if d.tokens.n == maxFlateBlockTokens {
-				// The block includes the current character
-				if d.err = d.writeBlockSkip(d.tokens, s.index, false); d.err != nil {
-					return
-				}
-				d.tokens.n = 0
-			}
-		} else {
-			s.ii++
-			end := s.index + int(s.ii>>5) + 1
-			if end > d.windowEnd {
-				end = d.windowEnd
-			}
-			for i := s.index; i < end; i++ {
-				d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[i]))
-				d.tokens.n++
-				if d.tokens.n == maxFlateBlockTokens {
-					if d.err = d.writeBlockSkip(d.tokens, i+1, false); d.err != nil {
-						return
-					}
-					d.tokens.n = 0
-				}
-			}
-			s.index = end
-		}
-	}
-}
-
-// deflateLazy is the same as deflate, but with d.fastSkipHashing == skipNever,
-// meaning it always has lazy matching on.
-func (d *compressor) deflateLazySSE() {
-	s := d.state
-	// Sanity enables additional runtime tests.
-	// It's intended to be used during development
-	// to supplement the currently ad-hoc unit tests.
-	const sanity = false
-
-	if d.windowEnd-s.index < minMatchLength+maxMatchLength && !d.sync {
-		return
-	}
-
-	s.maxInsertIndex = d.windowEnd - (minMatchLength - 1)
-	if s.index < s.maxInsertIndex {
-		s.hash = crc32sse(d.window[s.index:s.index+minMatchLength]) & hashMask
-	}
-
-	for {
-		if sanity && s.index > d.windowEnd {
-			panic("index > windowEnd")
-		}
-		lookahead := d.windowEnd - s.index
-		if lookahead < minMatchLength+maxMatchLength {
-			if !d.sync {
-				return
-			}
-			if sanity && s.index > d.windowEnd {
-				panic("index > windowEnd")
-			}
-			if lookahead == 0 {
-				// Flush current output block if any.
-				if d.byteAvailable {
-					// There is still one pending token that needs to be flushed
-					d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-					d.tokens.n++
-					d.byteAvailable = false
-				}
-				if d.tokens.n > 0 {
-					if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
-						return
-					}
-					d.tokens.n = 0
-				}
-				return
-			}
-		}
-		if s.index < s.maxInsertIndex {
-			// Update the hash
-			s.hash = crc32sse(d.window[s.index:s.index+minMatchLength]) & hashMask
-			ch := s.hashHead[s.hash]
-			s.chainHead = int(ch)
-			s.hashPrev[s.index&windowMask] = ch
-			s.hashHead[s.hash] = uint32(s.index + s.hashOffset)
-		}
-		prevLength := s.length
-		prevOffset := s.offset
-		s.length = minMatchLength - 1
-		s.offset = 0
-		minIndex := s.index - windowSize
-		if minIndex < 0 {
-			minIndex = 0
-		}
-
-		if s.chainHead-s.hashOffset >= minIndex && lookahead > prevLength && prevLength < d.lazy {
-			if newLength, newOffset, ok := d.findMatchSSE(s.index, s.chainHead-s.hashOffset, minMatchLength-1, lookahead); ok {
-				s.length = newLength
-				s.offset = newOffset
-			}
-		}
-		if prevLength >= minMatchLength && s.length <= prevLength {
-			// There was a match at the previous step, and the current match is
-			// not better. Output the previous match.
-			d.tokens.tokens[d.tokens.n] = matchToken(uint32(prevLength-3), uint32(prevOffset-minOffsetSize))
-			d.tokens.n++
-
-			// Insert in the hash table all strings up to the end of the match.
-			// index and index-1 are already inserted. If there is not enough
-			// lookahead, the last two strings are not inserted into the hash
-			// table.
-			var newIndex int
-			newIndex = s.index + prevLength - 1
-			// Calculate missing hashes
-			end := newIndex
-			if end > s.maxInsertIndex {
-				end = s.maxInsertIndex
-			}
-			end += minMatchLength - 1
-			startindex := s.index + 1
-			if startindex > s.maxInsertIndex {
-				startindex = s.maxInsertIndex
-			}
-			tocheck := d.window[startindex:end]
-			dstSize := len(tocheck) - minMatchLength + 1
-			if dstSize > 0 {
-				dst := s.hashMatch[:dstSize]
-				crc32sseAll(tocheck, dst)
-				var newH uint32
-				for i, val := range dst {
-					di := i + startindex
-					newH = val & hashMask
-					// Get previous value with the same hash.
-					// Our chain should point to the previous value.
-					s.hashPrev[di&windowMask] = s.hashHead[newH]
-					// Set the head of the hash chain to us.
-					s.hashHead[newH] = uint32(di + s.hashOffset)
-				}
-				s.hash = newH
-			}
-
-			s.index = newIndex
-			d.byteAvailable = false
-			s.length = minMatchLength - 1
-			if d.tokens.n == maxFlateBlockTokens {
-				// The block includes the current character
-				if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
-					return
-				}
-				d.tokens.n = 0
-			}
-		} else {
-			// Reset, if we got a match this run.
-			if s.length >= minMatchLength {
-				s.ii = 0
-			}
-			// We have a byte waiting. Emit it.
-			if d.byteAvailable {
-				s.ii++
-				d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-				d.tokens.n++
-				if d.tokens.n == maxFlateBlockTokens {
-					if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
-						return
-					}
-					d.tokens.n = 0
-				}
-				s.index++
-
-				// If we have a long run of no matches, skip additional bytes
-				// Resets when s.ii overflows after 64KB.
-				if s.ii > 31 {
-					n := int(s.ii >> 6)
-					for j := 0; j < n; j++ {
-						if s.index >= d.windowEnd-1 {
-							break
-						}
-
-						d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-						d.tokens.n++
-						if d.tokens.n == maxFlateBlockTokens {
-							if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
-								return
-							}
-							d.tokens.n = 0
-						}
-						s.index++
-					}
-					// Flush last byte
-					d.tokens.tokens[d.tokens.n] = literalToken(uint32(d.window[s.index-1]))
-					d.tokens.n++
-					d.byteAvailable = false
-					// s.length = minMatchLength - 1 // not needed, since s.ii is reset above, so it should never be > minMatchLength
-					if d.tokens.n == maxFlateBlockTokens {
-						if d.err = d.writeBlock(d.tokens, s.index, false); d.err != nil {
-							return
-						}
-						d.tokens.n = 0
+						d.tokens.Reset()
 					}
 				}
 			} else {
@@ -1085,17 +555,17 @@ func (d *compressor) storeHuff() {
 	if d.windowEnd < len(d.window) && !d.sync || d.windowEnd == 0 {
 		return
 	}
-	d.w.writeBlockHuff(false, d.window[:d.windowEnd])
+	d.w.writeBlockHuff(false, d.window[:d.windowEnd], d.sync)
 	d.err = d.w.err
 	d.windowEnd = 0
 }
 
-// storeHuff will compress and store the currently added data,
+// storeFast will compress and store the currently added data,
 // if enough has been accumulated or we at the end of the stream.
 // Any error that occurred will be in d.err
-func (d *compressor) storeSnappy() {
+func (d *compressor) storeFast() {
 	// We only compress if we have maxStoreBlockSize.
-	if d.windowEnd < maxStoreBlockSize {
+	if d.windowEnd < len(d.window) {
 		if !d.sync {
 			return
 		}
@@ -1106,32 +576,30 @@ func (d *compressor) storeSnappy() {
 			}
 			if d.windowEnd <= 32 {
 				d.err = d.writeStoredBlock(d.window[:d.windowEnd])
-				d.tokens.n = 0
-				d.windowEnd = 0
 			} else {
-				d.w.writeBlockHuff(false, d.window[:d.windowEnd])
+				d.w.writeBlockHuff(false, d.window[:d.windowEnd], true)
 				d.err = d.w.err
 			}
-			d.tokens.n = 0
+			d.tokens.Reset()
 			d.windowEnd = 0
-			d.snap.Reset()
+			d.fast.Reset()
 			return
 		}
 	}
 
-	d.snap.Encode(&d.tokens, d.window[:d.windowEnd])
+	d.fast.Encode(&d.tokens, d.window[:d.windowEnd])
 	// If we made zero matches, store the block as is.
-	if int(d.tokens.n) == d.windowEnd {
+	if d.tokens.n == 0 {
 		d.err = d.writeStoredBlock(d.window[:d.windowEnd])
 		// If we removed less than 1/16th, huffman compress the block.
 	} else if int(d.tokens.n) > d.windowEnd-(d.windowEnd>>4) {
-		d.w.writeBlockHuff(false, d.window[:d.windowEnd])
+		d.w.writeBlockHuff(false, d.window[:d.windowEnd], d.sync)
 		d.err = d.w.err
 	} else {
-		d.w.writeBlockDynamic(d.tokens.tokens[:d.tokens.n], false, d.window[:d.windowEnd])
+		d.w.writeBlockDynamic(&d.tokens, false, d.window[:d.windowEnd], d.sync)
 		d.err = d.w.err
 	}
-	d.tokens.n = 0
+	d.tokens.Reset()
 	d.windowEnd = 0
 }
 
@@ -1176,36 +644,26 @@ func (d *compressor) init(w io.Writer, level int) (err error) {
 		d.fill = (*compressor).fillBlock
 		d.step = (*compressor).store
 	case level == ConstantCompression:
+		d.w.logReusePenalty = uint(4)
 		d.window = make([]byte, maxStoreBlockSize)
 		d.fill = (*compressor).fillBlock
 		d.step = (*compressor).storeHuff
-	case level >= 1 && level <= 4:
-		d.snap = newFastEnc(level)
-		d.window = make([]byte, maxStoreBlockSize)
-		d.fill = (*compressor).fillBlock
-		d.step = (*compressor).storeSnappy
 	case level == DefaultCompression:
 		level = 5
 		fallthrough
-	case 5 <= level && level <= 9:
+	case level >= 1 && level <= 6:
+		d.w.logReusePenalty = uint(level + 1)
+		d.fast = newFastEnc(level)
+		d.window = make([]byte, maxStoreBlockSize)
+		d.fill = (*compressor).fillBlock
+		d.step = (*compressor).storeFast
+	case 7 <= level && level <= 9:
+		d.w.logReusePenalty = uint(level)
 		d.state = &advancedState{}
 		d.compressionLevel = levels[level]
 		d.initDeflate()
 		d.fill = (*compressor).fillDeflate
-		if d.fastSkipHashing == skipNever {
-			if useSSE42 {
-				d.step = (*compressor).deflateLazySSE
-			} else {
-				d.step = (*compressor).deflateLazy
-			}
-		} else {
-			if useSSE42 {
-				d.step = (*compressor).deflateSSE
-			} else {
-				d.step = (*compressor).deflate
-
-			}
-		}
+		d.step = (*compressor).deflateLazy
 	default:
 		return fmt.Errorf("flate: invalid compression level %d: want value in range [-2, 9]", level)
 	}
@@ -1218,10 +676,10 @@ func (d *compressor) reset(w io.Writer) {
 	d.sync = false
 	d.err = nil
 	// We only need to reset a few things for Snappy.
-	if d.snap != nil {
-		d.snap.Reset()
+	if d.fast != nil {
+		d.fast.Reset()
 		d.windowEnd = 0
-		d.tokens.n = 0
+		d.tokens.Reset()
 		return
 	}
 	switch d.compressionLevel.chain {
@@ -1240,7 +698,7 @@ func (d *compressor) reset(w io.Writer) {
 		s.hashOffset = 1
 		s.index, d.windowEnd = 0, 0
 		d.blockStart, d.byteAvailable = 0, false
-		d.tokens.n = 0
+		d.tokens.Reset()
 		s.length = minMatchLength - 1
 		s.offset = 0
 		s.hash = 0
diff --git a/vendor/github.com/klauspost/compress/flate/fast_encoder.go b/vendor/github.com/klauspost/compress/flate/fast_encoder.go
new file mode 100644
index 000000000..b0a470f92
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/fast_encoder.go
@@ -0,0 +1,257 @@
+// Copyright 2011 The Snappy-Go Authors. All rights reserved.
+// Modified for deflate by Klaus Post (c) 2015.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package flate
+
+import (
+	"fmt"
+	"math/bits"
+)
+
+type fastEnc interface {
+	Encode(dst *tokens, src []byte)
+	Reset()
+}
+
+func newFastEnc(level int) fastEnc {
+	switch level {
+	case 1:
+		return &fastEncL1{fastGen: fastGen{cur: maxStoreBlockSize}}
+	case 2:
+		return &fastEncL2{fastGen: fastGen{cur: maxStoreBlockSize}}
+	case 3:
+		return &fastEncL3{fastGen: fastGen{cur: maxStoreBlockSize}}
+	case 4:
+		return &fastEncL4{fastGen: fastGen{cur: maxStoreBlockSize}}
+	case 5:
+		return &fastEncL5{fastGen: fastGen{cur: maxStoreBlockSize}}
+	case 6:
+		return &fastEncL6{fastGen: fastGen{cur: maxStoreBlockSize}}
+	default:
+		panic("invalid level specified")
+	}
+}
+
+const (
+	tableBits       = 16             // Bits used in the table
+	tableSize       = 1 << tableBits // Size of the table
+	tableShift      = 32 - tableBits // Right-shift to get the tableBits most significant bits of a uint32.
+	baseMatchOffset = 1              // The smallest match offset
+	baseMatchLength = 3              // The smallest match length per the RFC section 3.2.5
+	maxMatchOffset  = 1 << 15        // The largest match offset
+
+	bTableBits   = 18                                           // Bits used in the big tables
+	bTableSize   = 1 << bTableBits                              // Size of the table
+	allocHistory = maxMatchOffset * 10                          // Size to preallocate for history.
+	bufferReset  = (1 << 31) - allocHistory - maxStoreBlockSize // Reset the buffer offset when reaching this.
+)
+
+const (
+	prime3bytes = 506832829
+	prime4bytes = 2654435761
+	prime5bytes = 889523592379
+	prime6bytes = 227718039650203
+	prime7bytes = 58295818150454627
+	prime8bytes = 0xcf1bbcdcb7a56463
+)
+
+func load32(b []byte, i int) uint32 {
+	// Help the compiler eliminate bounds checks on the read so it can be done in a single read.
+	b = b[i:]
+	b = b[:4]
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+}
+
+func load64(b []byte, i int) uint64 {
+	// Help the compiler eliminate bounds checks on the read so it can be done in a single read.
+	b = b[i:]
+	b = b[:8]
+	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+}
+
+func load3232(b []byte, i int32) uint32 {
+	// Help the compiler eliminate bounds checks on the read so it can be done in a single read.
+	b = b[i:]
+	b = b[:4]
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+}
+
+func load6432(b []byte, i int32) uint64 {
+	// Help the compiler eliminate bounds checks on the read so it can be done in a single read.
+	b = b[i:]
+	b = b[:8]
+	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+}
+
+func hash(u uint32) uint32 {
+	return (u * 0x1e35a7bd) >> tableShift
+}
+
+type tableEntry struct {
+	val    uint32
+	offset int32
+}
+
+// fastGen maintains the table for matches,
+// and the previous byte block for level 2.
+// This is the generic implementation.
+type fastGen struct {
+	hist []byte
+	cur  int32
+}
+
+func (e *fastGen) addBlock(src []byte) int32 {
+	// check if we have space already
+	if len(e.hist)+len(src) > cap(e.hist) {
+		if cap(e.hist) == 0 {
+			e.hist = make([]byte, 0, allocHistory)
+		} else {
+			if cap(e.hist) < maxMatchOffset*2 {
+				panic("unexpected buffer size")
+			}
+			// Move down
+			offset := int32(len(e.hist)) - maxMatchOffset
+			copy(e.hist[0:maxMatchOffset], e.hist[offset:])
+			e.cur += offset
+			e.hist = e.hist[:maxMatchOffset]
+		}
+	}
+	s := int32(len(e.hist))
+	e.hist = append(e.hist, src...)
+	return s
+}
+
+// hash4 returns the hash of u to fit in a hash table with h bits.
+// Preferably h should be a constant and should always be <32.
+func hash4u(u uint32, h uint8) uint32 {
+	return (u * prime4bytes) >> ((32 - h) & 31)
+}
+
+type tableEntryPrev struct {
+	Cur  tableEntry
+	Prev tableEntry
+}
+
+// hash4x64 returns the hash of the lowest 4 bytes of u to fit in a hash table with h bits.
+// Preferably h should be a constant and should always be <32.
+func hash4x64(u uint64, h uint8) uint32 {
+	return (uint32(u) * prime4bytes) >> ((32 - h) & 31)
+}
+
+// hash7 returns the hash of the lowest 7 bytes of u to fit in a hash table with h bits.
+// Preferably h should be a constant and should always be <64.
+func hash7(u uint64, h uint8) uint32 {
+	return uint32(((u << (64 - 56)) * prime7bytes) >> ((64 - h) & 63))
+}
+
+// hash8 returns the hash of u to fit in a hash table with h bits.
+// Preferably h should be a constant and should always be <64.
+func hash8(u uint64, h uint8) uint32 {
+	return uint32((u * prime8bytes) >> ((64 - h) & 63))
+}
+
+// hash6 returns the hash of the lowest 6 bytes of u to fit in a hash table with h bits.
+// Preferably h should be a constant and should always be <64.
+func hash6(u uint64, h uint8) uint32 {
+	return uint32(((u << (64 - 48)) * prime6bytes) >> ((64 - h) & 63))
+}
+
+// matchlen will return the match length between offsets and t in src.
+// The maximum length returned is maxMatchLength - 4.
+// It is assumed that s > t, that t >=0 and s < len(src).
+func (e *fastGen) matchlen(s, t int32, src []byte) int32 {
+	if debugDecode {
+		if t >= s {
+			panic(fmt.Sprint("t >=s:", t, s))
+		}
+		if int(s) >= len(src) {
+			panic(fmt.Sprint("s >= len(src):", s, len(src)))
+		}
+		if t < 0 {
+			panic(fmt.Sprint("t < 0:", t))
+		}
+		if s-t > maxMatchOffset {
+			panic(fmt.Sprint(s, "-", t, "(", s-t, ") > maxMatchLength (", maxMatchOffset, ")"))
+		}
+	}
+	s1 := int(s) + maxMatchLength - 4
+	if s1 > len(src) {
+		s1 = len(src)
+	}
+
+	// Extend the match to be as long as possible.
+	return int32(matchLen(src[s:s1], src[t:]))
+}
+
+// matchlenLong will return the match length between offsets and t in src.
+// It is assumed that s > t, that t >=0 and s < len(src).
+func (e *fastGen) matchlenLong(s, t int32, src []byte) int32 {
+	if debugDecode {
+		if t >= s {
+			panic(fmt.Sprint("t >=s:", t, s))
+		}
+		if int(s) >= len(src) {
+			panic(fmt.Sprint("s >= len(src):", s, len(src)))
+		}
+		if t < 0 {
+			panic(fmt.Sprint("t < 0:", t))
+		}
+		if s-t > maxMatchOffset {
+			panic(fmt.Sprint(s, "-", t, "(", s-t, ") > maxMatchLength (", maxMatchOffset, ")"))
+		}
+	}
+	// Extend the match to be as long as possible.
+	return int32(matchLen(src[s:], src[t:]))
+}
+
+// Reset the encoding table.
+func (e *fastGen) Reset() {
+	if cap(e.hist) < int(maxMatchOffset*8) {
+		l := maxMatchOffset * 8
+		// Make it at least 1MB.
+		if l < 1<<20 {
+			l = 1 << 20
+		}
+		e.hist = make([]byte, 0, l)
+	}
+	// We offset current position so everything will be out of reach
+	e.cur += maxMatchOffset + int32(len(e.hist))
+	e.hist = e.hist[:0]
+}
+
+// matchLen returns the maximum length.
+// 'a' must be the shortest of the two.
+func matchLen(a, b []byte) int {
+	b = b[:len(a)]
+	var checked int
+	if len(a) > 4 {
+		// Try 4 bytes first
+		if diff := load32(a, 0) ^ load32(b, 0); diff != 0 {
+			return bits.TrailingZeros32(diff) >> 3
+		}
+		// Switch to 8 byte matching.
+		checked = 4
+		a = a[4:]
+		b = b[4:]
+		for len(a) >= 8 {
+			b = b[:len(a)]
+			if diff := load64(a, 0) ^ load64(b, 0); diff != 0 {
+				return checked + (bits.TrailingZeros64(diff) >> 3)
+			}
+			checked += 8
+			a = a[8:]
+			b = b[8:]
+		}
+	}
+	b = b[:len(a)]
+	for i := range a {
+		if a[i] != b[i] {
+			return int(i) + checked
+		}
+	}
+	return len(a) + checked
+}
diff --git a/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go b/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go
index f46c65418..5ed476aa0 100644
--- a/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go
+++ b/vendor/github.com/klauspost/compress/flate/huffman_bit_writer.go
@@ -85,26 +85,48 @@ type huffmanBitWriter struct {
 	// Data waiting to be written is bytes[0:nbytes]
 	// and then the low nbits of bits.
 	bits            uint64
-	nbits           uint
-	bytes           [256]byte
-	codegenFreq     [codegenCodeCount]int32
+	nbits           uint16
 	nbytes          uint8
-	literalFreq     []int32
-	offsetFreq      []int32
-	codegen         []uint8
 	literalEncoding *huffmanEncoder
 	offsetEncoding  *huffmanEncoder
 	codegenEncoding *huffmanEncoder
 	err             error
+	lastHeader      int
+	// Set between 0 (reused block can be up to 2x the size)
+	logReusePenalty uint
+	lastHuffMan     bool
+	bytes           [256]byte
+	literalFreq     [lengthCodesStart + 32]uint16
+	offsetFreq      [32]uint16
+	codegenFreq     [codegenCodeCount]uint16
+
+	// codegen must have an extra space for the final symbol.
+	codegen [literalCount + offsetCodeCount + 1]uint8
 }
 
+// Huffman reuse.
+//
+// The huffmanBitWriter supports reusing huffman tables and thereby combining block sections.
+//
+// This is controlled by several variables:
+//
+// If lastHeader is non-zero the Huffman table can be reused.
+// This also indicates that a Huffman table has been generated that can output all
+// possible symbols.
+// It also indicates that an EOB has not yet been emitted, so if a new tabel is generated
+// an EOB with the previous table must be written.
+//
+// If lastHuffMan is set, a table for outputting literals has been generated and offsets are invalid.
+//
+// An incoming block estimates the output size of a new table using a 'fresh' by calculating the
+// optimal size and adding a penalty in 'logReusePenalty'.
+// A Huffman table is not optimal, which is why we add a penalty, and generating a new table
+// is slower both for compression and decompression.
+
 func newHuffmanBitWriter(w io.Writer) *huffmanBitWriter {
 	return &huffmanBitWriter{
 		writer:          w,
-		literalFreq:     make([]int32, lengthCodesStart+32),
-		offsetFreq:      make([]int32, 32),
-		codegen:         make([]uint8, maxNumLit+offsetCodeCount+1),
-		literalEncoding: newHuffmanEncoder(maxNumLit),
+		literalEncoding: newHuffmanEncoder(literalCount),
 		codegenEncoding: newHuffmanEncoder(codegenCodeCount),
 		offsetEncoding:  newHuffmanEncoder(offsetCodeCount),
 	}
@@ -114,6 +136,41 @@ func (w *huffmanBitWriter) reset(writer io.Writer) {
 	w.writer = writer
 	w.bits, w.nbits, w.nbytes, w.err = 0, 0, 0, nil
 	w.bytes = [256]byte{}
+	w.lastHeader = 0
+	w.lastHuffMan = false
+}
+
+func (w *huffmanBitWriter) canReuse(t *tokens) (offsets, lits bool) {
+	offsets, lits = true, true
+	a := t.offHist[:offsetCodeCount]
+	b := w.offsetFreq[:len(a)]
+	for i := range a {
+		if b[i] == 0 && a[i] != 0 {
+			offsets = false
+			break
+		}
+	}
+
+	a = t.extraHist[:literalCount-256]
+	b = w.literalFreq[256:literalCount]
+	b = b[:len(a)]
+	for i := range a {
+		if b[i] == 0 && a[i] != 0 {
+			lits = false
+			break
+		}
+	}
+	if lits {
+		a = t.litHist[:]
+		b = w.literalFreq[:len(a)]
+		for i := range a {
+			if b[i] == 0 && a[i] != 0 {
+				lits = false
+				break
+			}
+		}
+	}
+	return
 }
 
 func (w *huffmanBitWriter) flush() {
@@ -144,30 +201,11 @@ func (w *huffmanBitWriter) write(b []byte) {
 	_, w.err = w.writer.Write(b)
 }
 
-func (w *huffmanBitWriter) writeBits(b int32, nb uint) {
-	w.bits |= uint64(b) << w.nbits
+func (w *huffmanBitWriter) writeBits(b int32, nb uint16) {
+	w.bits |= uint64(b) << (w.nbits & 63)
 	w.nbits += nb
 	if w.nbits >= 48 {
-		bits := w.bits
-		w.bits >>= 48
-		w.nbits -= 48
-		n := w.nbytes
-		w.bytes[n] = byte(bits)
-		w.bytes[n+1] = byte(bits >> 8)
-		w.bytes[n+2] = byte(bits >> 16)
-		w.bytes[n+3] = byte(bits >> 24)
-		w.bytes[n+4] = byte(bits >> 32)
-		w.bytes[n+5] = byte(bits >> 40)
-		n += 6
-		if n >= bufferFlushSize {
-			if w.err != nil {
-				n = 0
-				return
-			}
-			w.write(w.bytes[:n])
-			n = 0
-		}
-		w.nbytes = n
+		w.writeOutBits()
 	}
 }
 
@@ -213,7 +251,7 @@ func (w *huffmanBitWriter) generateCodegen(numLiterals int, numOffsets int, litE
 	// a copy of the frequencies, and as the place where we put the result.
 	// This is fine because the output is always shorter than the input used
 	// so far.
-	codegen := w.codegen // cache
+	codegen := w.codegen[:] // cache
 	// Copy the concatenated code sizes to codegen. Put a marker at the end.
 	cgnl := codegen[:numLiterals]
 	for i := range cgnl {
@@ -292,30 +330,54 @@ func (w *huffmanBitWriter) generateCodegen(numLiterals int, numOffsets int, litE
 	codegen[outIndex] = badCode
 }
 
-// dynamicSize returns the size of dynamically encoded data in bits.
-func (w *huffmanBitWriter) dynamicSize(litEnc, offEnc *huffmanEncoder, extraBits int) (size, numCodegens int) {
+func (w *huffmanBitWriter) codegens() int {
+	numCodegens := len(w.codegenFreq)
+	for numCodegens > 4 && w.codegenFreq[codegenOrder[numCodegens-1]] == 0 {
+		numCodegens--
+	}
+	return numCodegens
+}
+
+func (w *huffmanBitWriter) headerSize() (size, numCodegens int) {
 	numCodegens = len(w.codegenFreq)
 	for numCodegens > 4 && w.codegenFreq[codegenOrder[numCodegens-1]] == 0 {
 		numCodegens--
 	}
-	header := 3 + 5 + 5 + 4 + (3 * numCodegens) +
+	return 3 + 5 + 5 + 4 + (3 * numCodegens) +
 		w.codegenEncoding.bitLength(w.codegenFreq[:]) +
 		int(w.codegenFreq[16])*2 +
 		int(w.codegenFreq[17])*3 +
-		int(w.codegenFreq[18])*7
+		int(w.codegenFreq[18])*7, numCodegens
+}
+
+// dynamicSize returns the size of dynamically encoded data in bits.
+func (w *huffmanBitWriter) dynamicSize(litEnc, offEnc *huffmanEncoder, extraBits int) (size, numCodegens int) {
+	header, numCodegens := w.headerSize()
 	size = header +
-		litEnc.bitLength(w.literalFreq) +
-		offEnc.bitLength(w.offsetFreq) +
+		litEnc.bitLength(w.literalFreq[:]) +
+		offEnc.bitLength(w.offsetFreq[:]) +
 		extraBits
-
 	return size, numCodegens
 }
 
+// extraBitSize will return the number of bits that will be written
+// as "extra" bits on matches.
+func (w *huffmanBitWriter) extraBitSize() int {
+	total := 0
+	for i, n := range w.literalFreq[257:literalCount] {
+		total += int(n) * int(lengthExtraBits[i&31])
+	}
+	for i, n := range w.offsetFreq[:offsetCodeCount] {
+		total += int(n) * int(offsetExtraBits[i&31])
+	}
+	return total
+}
+
 // fixedSize returns the size of dynamically encoded data in bits.
 func (w *huffmanBitWriter) fixedSize(extraBits int) int {
 	return 3 +
-		fixedLiteralEncoding.bitLength(w.literalFreq) +
-		fixedOffsetEncoding.bitLength(w.offsetFreq) +
+		fixedLiteralEncoding.bitLength(w.literalFreq[:]) +
+		fixedOffsetEncoding.bitLength(w.offsetFreq[:]) +
 		extraBits
 }
 
@@ -333,30 +395,36 @@ func (w *huffmanBitWriter) storedSize(in []byte) (int, bool) {
 }
 
 func (w *huffmanBitWriter) writeCode(c hcode) {
+	// The function does not get inlined if we "& 63" the shift.
 	w.bits |= uint64(c.code) << w.nbits
-	w.nbits += uint(c.len)
+	w.nbits += c.len
 	if w.nbits >= 48 {
-		bits := w.bits
-		w.bits >>= 48
-		w.nbits -= 48
-		n := w.nbytes
-		w.bytes[n] = byte(bits)
-		w.bytes[n+1] = byte(bits >> 8)
-		w.bytes[n+2] = byte(bits >> 16)
-		w.bytes[n+3] = byte(bits >> 24)
-		w.bytes[n+4] = byte(bits >> 32)
-		w.bytes[n+5] = byte(bits >> 40)
-		n += 6
-		if n >= bufferFlushSize {
-			if w.err != nil {
-				n = 0
-				return
-			}
-			w.write(w.bytes[:n])
+		w.writeOutBits()
+	}
+}
+
+// writeOutBits will write bits to the buffer.
+func (w *huffmanBitWriter) writeOutBits() {
+	bits := w.bits
+	w.bits >>= 48
+	w.nbits -= 48
+	n := w.nbytes
+	w.bytes[n] = byte(bits)
+	w.bytes[n+1] = byte(bits >> 8)
+	w.bytes[n+2] = byte(bits >> 16)
+	w.bytes[n+3] = byte(bits >> 24)
+	w.bytes[n+4] = byte(bits >> 32)
+	w.bytes[n+5] = byte(bits >> 40)
+	n += 6
+	if n >= bufferFlushSize {
+		if w.err != nil {
 			n = 0
+			return
 		}
-		w.nbytes = n
+		w.write(w.bytes[:n])
+		n = 0
 	}
+	w.nbytes = n
 }
 
 // Write the header of a dynamic Huffman block to the output stream.
@@ -412,6 +480,11 @@ func (w *huffmanBitWriter) writeStoredHeader(length int, isEof bool) {
 	if w.err != nil {
 		return
 	}
+	if w.lastHeader > 0 {
+		// We owe an EOB
+		w.writeCode(w.literalEncoding.codes[endBlockMarker])
+		w.lastHeader = 0
+	}
 	var flag int32
 	if isEof {
 		flag = 1
@@ -426,6 +499,12 @@ func (w *huffmanBitWriter) writeFixedHeader(isEof bool) {
 	if w.err != nil {
 		return
 	}
+	if w.lastHeader > 0 {
+		// We owe an EOB
+		w.writeCode(w.literalEncoding.codes[endBlockMarker])
+		w.lastHeader = 0
+	}
+
 	// Indicate that we are a fixed Huffman block
 	var value int32 = 2
 	if isEof {
@@ -439,29 +518,23 @@ func (w *huffmanBitWriter) writeFixedHeader(isEof bool) {
 // is larger than the original bytes, the data will be written as a
 // stored block.
 // If the input is nil, the tokens will always be Huffman encoded.
-func (w *huffmanBitWriter) writeBlock(tokens []token, eof bool, input []byte) {
+func (w *huffmanBitWriter) writeBlock(tokens *tokens, eof bool, input []byte) {
 	if w.err != nil {
 		return
 	}
 
-	tokens = append(tokens, endBlockMarker)
-	numLiterals, numOffsets := w.indexTokens(tokens)
-
+	tokens.AddEOB()
+	if w.lastHeader > 0 {
+		// We owe an EOB
+		w.writeCode(w.literalEncoding.codes[endBlockMarker])
+		w.lastHeader = 0
+	}
+	numLiterals, numOffsets := w.indexTokens(tokens, false)
+	w.generate(tokens)
 	var extraBits int
 	storedSize, storable := w.storedSize(input)
 	if storable {
-		// We only bother calculating the costs of the extra bits required by
-		// the length of offset fields (which will be the same for both fixed
-		// and dynamic encoding), if we need to compare those two encodings
-		// against stored encoding.
-		for lengthCode := lengthCodesStart + 8; lengthCode < numLiterals; lengthCode++ {
-			// First eight length codes have extra size = 0.
-			extraBits += int(w.literalFreq[lengthCode]) * int(lengthExtraBits[lengthCode-lengthCodesStart])
-		}
-		for offsetCode := 4; offsetCode < numOffsets; offsetCode++ {
-			// First four offset codes have extra size = 0.
-			extraBits += int(w.offsetFreq[offsetCode]) * int(offsetExtraBits[offsetCode&63])
-		}
+		extraBits = w.extraBitSize()
 	}
 
 	// Figure out smallest code.
@@ -500,7 +573,7 @@ func (w *huffmanBitWriter) writeBlock(tokens []token, eof bool, input []byte) {
 	}
 
 	// Write the tokens.
-	w.writeTokens(tokens, literalEncoding.codes, offsetEncoding.codes)
+	w.writeTokens(tokens.Slice(), literalEncoding.codes, offsetEncoding.codes)
 }
 
 // writeBlockDynamic encodes a block using a dynamic Huffman table.
@@ -508,72 +581,103 @@ func (w *huffmanBitWriter) writeBlock(tokens []token, eof bool, input []byte) {
 // histogram distribution.
 // If input is supplied and the compression savings are below 1/16th of the
 // input size the block is stored.
-func (w *huffmanBitWriter) writeBlockDynamic(tokens []token, eof bool, input []byte) {
+func (w *huffmanBitWriter) writeBlockDynamic(tokens *tokens, eof bool, input []byte, sync bool) {
 	if w.err != nil {
 		return
 	}
 
-	tokens = append(tokens, endBlockMarker)
-	numLiterals, numOffsets := w.indexTokens(tokens)
+	sync = sync || eof
+	if sync {
+		tokens.AddEOB()
+	}
 
-	// Generate codegen and codegenFrequencies, which indicates how to encode
-	// the literalEncoding and the offsetEncoding.
-	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
-	w.codegenEncoding.generate(w.codegenFreq[:], 7)
-	size, numCodegens := w.dynamicSize(w.literalEncoding, w.offsetEncoding, 0)
+	// We cannot reuse pure huffman table.
+	if w.lastHuffMan && w.lastHeader > 0 {
+		// We will not try to reuse.
+		w.writeCode(w.literalEncoding.codes[endBlockMarker])
+		w.lastHeader = 0
+		w.lastHuffMan = false
+	}
+	if !sync {
+		tokens.Fill()
+	}
+	numLiterals, numOffsets := w.indexTokens(tokens, !sync)
 
-	// Store bytes, if we don't get a reasonable improvement.
-	if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
-		w.writeStoredHeader(len(input), eof)
-		w.writeBytes(input)
-		return
+	var size int
+	// Check if we should reuse.
+	if w.lastHeader > 0 {
+		// Estimate size for using a new table
+		newSize := w.lastHeader + tokens.EstimatedBits()
+
+		// The estimated size is calculated as an optimal table.
+		// We add a penalty to make it more realistic and re-use a bit more.
+		newSize += newSize >> (w.logReusePenalty & 31)
+		extra := w.extraBitSize()
+		reuseSize, _ := w.dynamicSize(w.literalEncoding, w.offsetEncoding, extra)
+
+		// Check if a new table is better.
+		if newSize < reuseSize {
+			// Write the EOB we owe.
+			w.writeCode(w.literalEncoding.codes[endBlockMarker])
+			size = newSize
+			w.lastHeader = 0
+		} else {
+			size = reuseSize
+		}
+		// Check if we get a reasonable size decrease.
+		if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
+			w.writeStoredHeader(len(input), eof)
+			w.writeBytes(input)
+			w.lastHeader = 0
+			return
+		}
 	}
 
-	// Write Huffman table.
-	w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
+	// We want a new block/table
+	if w.lastHeader == 0 {
+		w.generate(tokens)
+		// Generate codegen and codegenFrequencies, which indicates how to encode
+		// the literalEncoding and the offsetEncoding.
+		w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, w.offsetEncoding)
+		w.codegenEncoding.generate(w.codegenFreq[:], 7)
+		var numCodegens int
+		size, numCodegens = w.dynamicSize(w.literalEncoding, w.offsetEncoding, w.extraBitSize())
+		// Store bytes, if we don't get a reasonable improvement.
+		if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
+			w.writeStoredHeader(len(input), eof)
+			w.writeBytes(input)
+			w.lastHeader = 0
+			return
+		}
+
+		// Write Huffman table.
+		w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
+		w.lastHeader, _ = w.headerSize()
+		w.lastHuffMan = false
+	}
 
+	if sync {
+		w.lastHeader = 0
+	}
 	// Write the tokens.
-	w.writeTokens(tokens, w.literalEncoding.codes, w.offsetEncoding.codes)
+	w.writeTokens(tokens.Slice(), w.literalEncoding.codes, w.offsetEncoding.codes)
 }
 
 // indexTokens indexes a slice of tokens, and updates
 // literalFreq and offsetFreq, and generates literalEncoding
 // and offsetEncoding.
 // The number of literal and offset tokens is returned.
-func (w *huffmanBitWriter) indexTokens(tokens []token) (numLiterals, numOffsets int) {
-	for i := range w.literalFreq {
-		w.literalFreq[i] = 0
-	}
-	for i := range w.offsetFreq {
-		w.offsetFreq[i] = 0
-	}
+func (w *huffmanBitWriter) indexTokens(t *tokens, filled bool) (numLiterals, numOffsets int) {
+	copy(w.literalFreq[:], t.litHist[:])
+	copy(w.literalFreq[256:], t.extraHist[:])
+	copy(w.offsetFreq[:], t.offHist[:offsetCodeCount])
 
-	if len(tokens) == 0 {
+	if t.n == 0 {
 		return
 	}
-
-	// Only last token should be endBlockMarker.
-	if tokens[len(tokens)-1] == endBlockMarker {
-		w.literalFreq[endBlockMarker]++
-		tokens = tokens[:len(tokens)-1]
+	if filled {
+		return maxNumLit, maxNumDist
 	}
-
-	// Create slices up to the next power of two to avoid bounds checks.
-	lits := w.literalFreq[:256]
-	offs := w.offsetFreq[:32]
-	lengths := w.literalFreq[lengthCodesStart:]
-	lengths = lengths[:32]
-	for _, t := range tokens {
-		if t < endBlockMarker {
-			lits[t.literal()]++
-			continue
-		}
-		length := t.length()
-		offset := t.offset()
-		lengths[lengthCode(length)&31]++
-		offs[offsetCode(offset)&31]++
-	}
-
 	// get the number of literals
 	numLiterals = len(w.literalFreq)
 	for w.literalFreq[numLiterals-1] == 0 {
@@ -590,11 +694,14 @@ func (w *huffmanBitWriter) indexTokens(tokens []token) (numLiterals, numOffsets
 		w.offsetFreq[0] = 1
 		numOffsets = 1
 	}
-	w.literalEncoding.generate(w.literalFreq[:maxNumLit], 15)
-	w.offsetEncoding.generate(w.offsetFreq[:offsetCodeCount], 15)
 	return
 }
 
+func (w *huffmanBitWriter) generate(t *tokens) {
+	w.literalEncoding.generate(w.literalFreq[:literalCount], 15)
+	w.offsetEncoding.generate(w.offsetFreq[:offsetCodeCount], 15)
+}
+
 // writeTokens writes a slice of tokens to the output.
 // codes for literal and offset encoding must be supplied.
 func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode) {
@@ -626,8 +733,19 @@ func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode)
 		// Write the length
 		length := t.length()
 		lengthCode := lengthCode(length)
-		w.writeCode(lengths[lengthCode&31])
-		extraLengthBits := uint(lengthExtraBits[lengthCode&31])
+		if false {
+			w.writeCode(lengths[lengthCode&31])
+		} else {
+			// inlined
+			c := lengths[lengthCode&31]
+			w.bits |= uint64(c.code) << (w.nbits & 63)
+			w.nbits += c.len
+			if w.nbits >= 48 {
+				w.writeOutBits()
+			}
+		}
+
+		extraLengthBits := uint16(lengthExtraBits[lengthCode&31])
 		if extraLengthBits > 0 {
 			extraLength := int32(length - lengthBase[lengthCode&31])
 			w.writeBits(extraLength, extraLengthBits)
@@ -635,8 +753,18 @@ func (w *huffmanBitWriter) writeTokens(tokens []token, leCodes, oeCodes []hcode)
 		// Write the offset
 		offset := t.offset()
 		offsetCode := offsetCode(offset)
-		w.writeCode(offs[offsetCode&31])
-		extraOffsetBits := uint(offsetExtraBits[offsetCode&63])
+		if false {
+			w.writeCode(offs[offsetCode&31])
+		} else {
+			// inlined
+			c := offs[offsetCode&31]
+			w.bits |= uint64(c.code) << (w.nbits & 63)
+			w.nbits += c.len
+			if w.nbits >= 48 {
+				w.writeOutBits()
+			}
+		}
+		extraOffsetBits := uint16(offsetExtraBits[offsetCode&63])
 		if extraOffsetBits > 0 {
 			extraOffset := int32(offset - offsetBase[offsetCode&63])
 			w.writeBits(extraOffset, extraOffsetBits)
@@ -661,75 +789,93 @@ func init() {
 // writeBlockHuff encodes a block of bytes as either
 // Huffman encoded literals or uncompressed bytes if the
 // results only gains very little from compression.
-func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte) {
+func (w *huffmanBitWriter) writeBlockHuff(eof bool, input []byte, sync bool) {
 	if w.err != nil {
 		return
 	}
 
 	// Clear histogram
-	for i := range w.literalFreq {
+	for i := range w.literalFreq[:] {
 		w.literalFreq[i] = 0
 	}
+	if !w.lastHuffMan {
+		for i := range w.offsetFreq[:] {
+			w.offsetFreq[i] = 0
+		}
+	}
 
 	// Add everything as literals
-	histogram(input, w.literalFreq)
+	estBits := histogramSize(input, w.literalFreq[:], !eof && !sync) + 15
 
-	w.literalFreq[endBlockMarker] = 1
+	// Store bytes, if we don't get a reasonable improvement.
+	ssize, storable := w.storedSize(input)
+	if storable && ssize < (estBits+estBits>>4) {
+		w.writeStoredHeader(len(input), eof)
+		w.writeBytes(input)
+		return
+	}
 
-	const numLiterals = endBlockMarker + 1
-	const numOffsets = 1
+	if w.lastHeader > 0 {
+		size, _ := w.dynamicSize(w.literalEncoding, huffOffset, w.lastHeader)
+		estBits += estBits >> (w.logReusePenalty)
 
-	w.literalEncoding.generate(w.literalFreq[:maxNumLit], 15)
+		if estBits < size {
+			// We owe an EOB
+			w.writeCode(w.literalEncoding.codes[endBlockMarker])
+			w.lastHeader = 0
+		}
+	}
 
-	// Figure out smallest code.
-	// Always use dynamic Huffman or Store
-	var numCodegens int
+	const numLiterals = endBlockMarker + 1
+	const numOffsets = 1
+	if w.lastHeader == 0 {
+		w.literalFreq[endBlockMarker] = 1
+		w.literalEncoding.generate(w.literalFreq[:numLiterals], 15)
 
-	// Generate codegen and codegenFrequencies, which indicates how to encode
-	// the literalEncoding and the offsetEncoding.
-	w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, huffOffset)
-	w.codegenEncoding.generate(w.codegenFreq[:], 7)
-	size, numCodegens := w.dynamicSize(w.literalEncoding, huffOffset, 0)
+		// Generate codegen and codegenFrequencies, which indicates how to encode
+		// the literalEncoding and the offsetEncoding.
+		w.generateCodegen(numLiterals, numOffsets, w.literalEncoding, huffOffset)
+		w.codegenEncoding.generate(w.codegenFreq[:], 7)
+		numCodegens := w.codegens()
 
-	// Store bytes, if we don't get a reasonable improvement.
-	if ssize, storable := w.storedSize(input); storable && ssize < (size+size>>4) {
-		w.writeStoredHeader(len(input), eof)
-		w.writeBytes(input)
-		return
+		// Huffman.
+		w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
+		w.lastHuffMan = true
+		w.lastHeader, _ = w.headerSize()
 	}
 
-	// Huffman.
-	w.writeDynamicHeader(numLiterals, numOffsets, numCodegens, eof)
 	encoding := w.literalEncoding.codes[:257]
-	n := w.nbytes
 	for _, t := range input {
 		// Bitwriting inlined, ~30% speedup
 		c := encoding[t]
-		w.bits |= uint64(c.code) << w.nbits
-		w.nbits += uint(c.len)
-		if w.nbits < 48 {
-			continue
-		}
-		// Store 6 bytes
-		bits := w.bits
-		w.bits >>= 48
-		w.nbits -= 48
-		w.bytes[n] = byte(bits)
-		w.bytes[n+1] = byte(bits >> 8)
-		w.bytes[n+2] = byte(bits >> 16)
-		w.bytes[n+3] = byte(bits >> 24)
-		w.bytes[n+4] = byte(bits >> 32)
-		w.bytes[n+5] = byte(bits >> 40)
-		n += 6
-		if n < bufferFlushSize {
-			continue
-		}
-		w.write(w.bytes[:n])
-		if w.err != nil {
-			return // Return early in the event of write failures
+		w.bits |= uint64(c.code) << ((w.nbits) & 63)
+		w.nbits += c.len
+		if w.nbits >= 48 {
+			bits := w.bits
+			w.bits >>= 48
+			w.nbits -= 48
+			n := w.nbytes
+			w.bytes[n] = byte(bits)
+			w.bytes[n+1] = byte(bits >> 8)
+			w.bytes[n+2] = byte(bits >> 16)
+			w.bytes[n+3] = byte(bits >> 24)
+			w.bytes[n+4] = byte(bits >> 32)
+			w.bytes[n+5] = byte(bits >> 40)
+			n += 6
+			if n >= bufferFlushSize {
+				if w.err != nil {
+					n = 0
+					return
+				}
+				w.write(w.bytes[:n])
+				n = 0
+			}
+			w.nbytes = n
 		}
-		n = 0
 	}
-	w.nbytes = n
-	w.writeCode(encoding[endBlockMarker])
+	if eof || sync {
+		w.writeCode(encoding[endBlockMarker])
+		w.lastHeader = 0
+		w.lastHuffMan = false
+	}
 }
diff --git a/vendor/github.com/klauspost/compress/flate/huffman_code.go b/vendor/github.com/klauspost/compress/flate/huffman_code.go
index f65f79336..d0099599c 100644
--- a/vendor/github.com/klauspost/compress/flate/huffman_code.go
+++ b/vendor/github.com/klauspost/compress/flate/huffman_code.go
@@ -10,6 +10,12 @@ import (
 	"sort"
 )
 
+const (
+	maxBitsLimit = 16
+	// number of valid literals
+	literalCount = 286
+)
+
 // hcode is a huffman code with a bit code and bit length.
 type hcode struct {
 	code, len uint16
@@ -25,7 +31,7 @@ type huffmanEncoder struct {
 
 type literalNode struct {
 	literal uint16
-	freq    int32
+	freq    uint16
 }
 
 // A levelInfo describes the state of the constructed tree for a given depth.
@@ -54,7 +60,11 @@ func (h *hcode) set(code uint16, length uint16) {
 	h.code = code
 }
 
-func maxNode() literalNode { return literalNode{math.MaxUint16, math.MaxInt32} }
+func reverseBits(number uint16, bitLength byte) uint16 {
+	return bits.Reverse16(number << ((16 - bitLength) & 15))
+}
+
+func maxNode() literalNode { return literalNode{math.MaxUint16, math.MaxUint16} }
 
 func newHuffmanEncoder(size int) *huffmanEncoder {
 	// Make capacity to next power of two.
@@ -64,10 +74,10 @@ func newHuffmanEncoder(size int) *huffmanEncoder {
 
 // Generates a HuffmanCode corresponding to the fixed literal table
 func generateFixedLiteralEncoding() *huffmanEncoder {
-	h := newHuffmanEncoder(maxNumLit)
+	h := newHuffmanEncoder(literalCount)
 	codes := h.codes
 	var ch uint16
-	for ch = 0; ch < maxNumLit; ch++ {
+	for ch = 0; ch < literalCount; ch++ {
 		var bits uint16
 		var size uint16
 		switch {
@@ -108,7 +118,7 @@ func generateFixedOffsetEncoding() *huffmanEncoder {
 var fixedLiteralEncoding *huffmanEncoder = generateFixedLiteralEncoding()
 var fixedOffsetEncoding *huffmanEncoder = generateFixedOffsetEncoding()
 
-func (h *huffmanEncoder) bitLength(freq []int32) int {
+func (h *huffmanEncoder) bitLength(freq []uint16) int {
 	var total int
 	for i, f := range freq {
 		if f != 0 {
@@ -118,8 +128,6 @@ func (h *huffmanEncoder) bitLength(freq []int32) int {
 	return total
 }
 
-const maxBitsLimit = 16
-
 // Return the number of literals assigned to each bit size in the Huffman encoding
 //
 // This method is only called when list.length >= 3
@@ -163,9 +171,9 @@ func (h *huffmanEncoder) bitCounts(list []literalNode, maxBits int32) []int32 {
 		// We initialize the levels as if we had already figured this out.
 		levels[level] = levelInfo{
 			level:        level,
-			lastFreq:     list[1].freq,
-			nextCharFreq: list[2].freq,
-			nextPairFreq: list[0].freq + list[1].freq,
+			lastFreq:     int32(list[1].freq),
+			nextCharFreq: int32(list[2].freq),
+			nextPairFreq: int32(list[0].freq) + int32(list[1].freq),
 		}
 		leafCounts[level][level] = 2
 		if level == 1 {
@@ -197,7 +205,12 @@ func (h *huffmanEncoder) bitCounts(list []literalNode, maxBits int32) []int32 {
 			l.lastFreq = l.nextCharFreq
 			// Lower leafCounts are the same of the previous node.
 			leafCounts[level][level] = n
-			l.nextCharFreq = list[n].freq
+			e := list[n]
+			if e.literal < math.MaxUint16 {
+				l.nextCharFreq = int32(e.freq)
+			} else {
+				l.nextCharFreq = math.MaxInt32
+			}
 		} else {
 			// The next item on this row is a pair from the previous row.
 			// nextPairFreq isn't valid until we generate two
@@ -273,12 +286,12 @@ func (h *huffmanEncoder) assignEncodingAndSize(bitCount []int32, list []literalN
 //
 // freq  An array of frequencies, in which frequency[i] gives the frequency of literal i.
 // maxBits  The maximum number of bits to use for any literal.
-func (h *huffmanEncoder) generate(freq []int32, maxBits int32) {
+func (h *huffmanEncoder) generate(freq []uint16, maxBits int32) {
 	if h.freqcache == nil {
 		// Allocate a reusable buffer with the longest possible frequency table.
-		// Possible lengths are codegenCodeCount, offsetCodeCount and maxNumLit.
-		// The largest of these is maxNumLit, so we allocate for that case.
-		h.freqcache = make([]literalNode, maxNumLit+1)
+		// Possible lengths are codegenCodeCount, offsetCodeCount and literalCount.
+		// The largest of these is literalCount, so we allocate for that case.
+		h.freqcache = make([]literalNode, literalCount+1)
 	}
 	list := h.freqcache[:len(freq)+1]
 	// Number of non-zero literals
@@ -345,3 +358,27 @@ func (s byFreq) Less(i, j int) bool {
 }
 
 func (s byFreq) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+// histogramSize accumulates a histogram of b in h.
+// An estimated size in bits is returned.
+// Unassigned values are assigned '1' in the histogram.
+// len(h) must be >= 256, and h's elements must be all zeroes.
+func histogramSize(b []byte, h []uint16, fill bool) int {
+	h = h[:256]
+	for _, t := range b {
+		h[t]++
+	}
+	invTotal := 1.0 / float64(len(b))
+	shannon := 0.0
+	single := math.Ceil(-math.Log2(invTotal))
+	for i, v := range h[:] {
+		if v > 0 {
+			n := float64(v)
+			shannon += math.Ceil(-math.Log2(n*invTotal) * n)
+		} else if fill {
+			shannon += single
+			h[i] = 1
+		}
+	}
+	return int(shannon + 0.99)
+}
diff --git a/vendor/github.com/klauspost/compress/flate/inflate.go b/vendor/github.com/klauspost/compress/flate/inflate.go
index 800d0ce9e..6dc5b5d06 100644
--- a/vendor/github.com/klauspost/compress/flate/inflate.go
+++ b/vendor/github.com/klauspost/compress/flate/inflate.go
@@ -9,6 +9,7 @@ package flate
 
 import (
 	"bufio"
+	"fmt"
 	"io"
 	"math/bits"
 	"strconv"
@@ -24,6 +25,8 @@ const (
 	maxNumLit  = 286
 	maxNumDist = 30
 	numCodes   = 19 // number of codes in Huffman meta-code
+
+	debugDecode = false
 )
 
 // Initialize the fixedHuffmanDecoder only once upon first use.
@@ -104,8 +107,8 @@ const (
 
 type huffmanDecoder struct {
 	min      int                       // the minimum code length
-	chunks   *[huffmanNumChunks]uint32 // chunks as described above
-	links    [][]uint32                // overflow links
+	chunks   *[huffmanNumChunks]uint16 // chunks as described above
+	links    [][]uint16                // overflow links
 	linkMask uint32                    // mask the width of the link table
 }
 
@@ -121,7 +124,7 @@ func (h *huffmanDecoder) init(lengths []int) bool {
 	const sanity = false
 
 	if h.chunks == nil {
-		h.chunks = &[huffmanNumChunks]uint32{}
+		h.chunks = &[huffmanNumChunks]uint16{}
 	}
 	if h.min != 0 {
 		*h = huffmanDecoder{chunks: h.chunks, links: h.links}
@@ -169,6 +172,9 @@ func (h *huffmanDecoder) init(lengths []int) bool {
 	// accept degenerate single-code codings. See also
 	// TestDegenerateHuffmanCoding.
 	if code != 1<<uint(max) && !(code == 1 && max == 1) {
+		if debugDecode {
+			fmt.Println("coding failed, code, max:", code, max, code == 1<<uint(max), code == 1 && max == 1, "(one should be true)")
+		}
 		return false
 	}
 
@@ -185,7 +191,7 @@ func (h *huffmanDecoder) init(lengths []int) bool {
 		// create link tables
 		link := nextcode[huffmanChunkBits+1] >> 1
 		if cap(h.links) < huffmanNumChunks-link {
-			h.links = make([][]uint32, huffmanNumChunks-link)
+			h.links = make([][]uint16, huffmanNumChunks-link)
 		} else {
 			h.links = h.links[:huffmanNumChunks-link]
 		}
@@ -196,9 +202,9 @@ func (h *huffmanDecoder) init(lengths []int) bool {
 			if sanity && h.chunks[reverse] != 0 {
 				panic("impossible: overwriting existing chunk")
 			}
-			h.chunks[reverse] = uint32(off<<huffmanValueShift | (huffmanChunkBits + 1))
+			h.chunks[reverse] = uint16(off<<huffmanValueShift | (huffmanChunkBits + 1))
 			if cap(h.links[off]) < numLinks {
-				h.links[off] = make([]uint32, numLinks)
+				h.links[off] = make([]uint16, numLinks)
 			} else {
 				links := h.links[off][:0]
 				h.links[off] = links[:numLinks]
@@ -214,7 +220,7 @@ func (h *huffmanDecoder) init(lengths []int) bool {
 		}
 		code := nextcode[n]
 		nextcode[n]++
-		chunk := uint32(i<<huffmanValueShift | n)
+		chunk := uint16(i<<huffmanValueShift | n)
 		reverse := int(bits.Reverse16(uint16(code)))
 		reverse >>= uint(16 - n)
 		if n <= huffmanChunkBits {
@@ -347,6 +353,9 @@ func (f *decompressor) nextBlock() {
 		f.huffmanBlock()
 	default:
 		// 3 is reserved.
+		if debugDecode {
+			fmt.Println("reserved data block encountered")
+		}
 		f.err = CorruptInputError(f.roffset)
 	}
 }
@@ -425,11 +434,17 @@ func (f *decompressor) readHuffman() error {
 	}
 	nlit := int(f.b&0x1F) + 257
 	if nlit > maxNumLit {
+		if debugDecode {
+			fmt.Println("nlit > maxNumLit", nlit)
+		}
 		return CorruptInputError(f.roffset)
 	}
 	f.b >>= 5
 	ndist := int(f.b&0x1F) + 1
 	if ndist > maxNumDist {
+		if debugDecode {
+			fmt.Println("ndist > maxNumDist", ndist)
+		}
 		return CorruptInputError(f.roffset)
 	}
 	f.b >>= 5
@@ -453,6 +468,9 @@ func (f *decompressor) readHuffman() error {
 		f.codebits[codeOrder[i]] = 0
 	}
 	if !f.h1.init(f.codebits[0:]) {
+		if debugDecode {
+			fmt.Println("init codebits failed")
+		}
 		return CorruptInputError(f.roffset)
 	}
 
@@ -480,6 +498,9 @@ func (f *decompressor) readHuffman() error {
 			rep = 3
 			nb = 2
 			if i == 0 {
+				if debugDecode {
+					fmt.Println("i==0")
+				}
 				return CorruptInputError(f.roffset)
 			}
 			b = f.bits[i-1]
@@ -494,6 +515,9 @@ func (f *decompressor) readHuffman() error {
 		}
 		for f.nb < nb {
 			if err := f.moreBits(); err != nil {
+				if debugDecode {
+					fmt.Println("morebits:", err)
+				}
 				return err
 			}
 		}
@@ -501,6 +525,9 @@ func (f *decompressor) readHuffman() error {
 		f.b >>= nb
 		f.nb -= nb
 		if i+rep > n {
+			if debugDecode {
+				fmt.Println("i+rep > n", i, rep, n)
+			}
 			return CorruptInputError(f.roffset)
 		}
 		for j := 0; j < rep; j++ {
@@ -510,6 +537,9 @@ func (f *decompressor) readHuffman() error {
 	}
 
 	if !f.h1.init(f.bits[0:nlit]) || !f.h2.init(f.bits[nlit:nlit+ndist]) {
+		if debugDecode {
+			fmt.Println("init2 failed")
+		}
 		return CorruptInputError(f.roffset)
 	}
 
@@ -587,12 +617,18 @@ readLiteral:
 			length = 258
 			n = 0
 		default:
+			if debugDecode {
+				fmt.Println(v, ">= maxNumLit")
+			}
 			f.err = CorruptInputError(f.roffset)
 			return
 		}
 		if n > 0 {
 			for f.nb < n {
 				if err = f.moreBits(); err != nil {
+					if debugDecode {
+						fmt.Println("morebits n>0:", err)
+					}
 					f.err = err
 					return
 				}
@@ -606,6 +642,9 @@ readLiteral:
 		if f.hd == nil {
 			for f.nb < 5 {
 				if err = f.moreBits(); err != nil {
+					if debugDecode {
+						fmt.Println("morebits f.nb<5:", err)
+					}
 					f.err = err
 					return
 				}
@@ -615,6 +654,9 @@ readLiteral:
 			f.nb -= 5
 		} else {
 			if dist, err = f.huffSym(f.hd); err != nil {
+				if debugDecode {
+					fmt.Println("huffsym:", err)
+				}
 				f.err = err
 				return
 			}
@@ -629,6 +671,9 @@ readLiteral:
 			extra := (dist & 1) << nb
 			for f.nb < nb {
 				if err = f.moreBits(); err != nil {
+					if debugDecode {
+						fmt.Println("morebits f.nb<nb:", err)
+					}
 					f.err = err
 					return
 				}
@@ -638,12 +683,18 @@ readLiteral:
 			f.nb -= nb
 			dist = 1<<(nb+1) + 1 + extra
 		default:
+			if debugDecode {
+				fmt.Println("dist too big:", dist, maxNumDist)
+			}
 			f.err = CorruptInputError(f.roffset)
 			return
 		}
 
 		// No check on length; encoding can be prescient.
 		if dist > f.dict.histSize() {
+			if debugDecode {
+				fmt.Println("dist > f.dict.histSize():", dist, f.dict.histSize())
+			}
 			f.err = CorruptInputError(f.roffset)
 			return
 		}
@@ -688,6 +739,9 @@ func (f *decompressor) dataBlock() {
 	n := int(f.buf[0]) | int(f.buf[1])<<8
 	nn := int(f.buf[2]) | int(f.buf[3])<<8
 	if uint16(nn) != uint16(^n) {
+		if debugDecode {
+			fmt.Println("uint16(nn) != uint16(^n)", nn, ^n)
+		}
 		f.err = CorruptInputError(f.roffset)
 		return
 	}
@@ -789,6 +843,9 @@ func (f *decompressor) huffSym(h *huffmanDecoder) (int, error) {
 			if n == 0 {
 				f.b = b
 				f.nb = nb
+				if debugDecode {
+					fmt.Println("huffsym: n==0")
+				}
 				f.err = CorruptInputError(f.roffset)
 				return 0, f.err
 			}
diff --git a/vendor/github.com/klauspost/compress/flate/level1.go b/vendor/github.com/klauspost/compress/flate/level1.go
new file mode 100644
index 000000000..20de8f11f
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/level1.go
@@ -0,0 +1,174 @@
+package flate
+
+// fastGen maintains the table for matches,
+// and the previous byte block for level 2.
+// This is the generic implementation.
+type fastEncL1 struct {
+	fastGen
+	table [tableSize]tableEntry
+}
+
+// EncodeL1 uses a similar algorithm to level 1
+func (e *fastEncL1) Encode(dst *tokens, src []byte) {
+	const (
+		inputMargin            = 12 - 1
+		minNonLiteralBlockSize = 1 + 1 + inputMargin
+	)
+
+	// Protect against e.cur wraparound.
+	for e.cur >= bufferReset {
+		if len(e.hist) == 0 {
+			for i := range e.table[:] {
+				e.table[i] = tableEntry{}
+			}
+			e.cur = maxMatchOffset
+			break
+		}
+		// Shift down everything in the table that isn't already too far away.
+		minOff := e.cur + int32(len(e.hist)) - maxMatchOffset
+		for i := range e.table[:] {
+			v := e.table[i].offset
+			if v <= minOff {
+				v = 0
+			} else {
+				v = v - e.cur + maxMatchOffset
+			}
+			e.table[i].offset = v
+		}
+		e.cur = maxMatchOffset
+	}
+
+	s := e.addBlock(src)
+
+	// This check isn't in the Snappy implementation, but there, the caller
+	// instead of the callee handles this case.
+	if len(src) < minNonLiteralBlockSize {
+		// We do not fill the token table.
+		// This will be picked up by caller.
+		dst.n = uint16(len(src))
+		return
+	}
+
+	// Override src
+	src = e.hist
+	nextEmit := s
+
+	// sLimit is when to stop looking for offset/length copies. The inputMargin
+	// lets us use a fast path for emitLiteral in the main loop, while we are
+	// looking for copies.
+	sLimit := int32(len(src) - inputMargin)
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	cv := load3232(src, s)
+
+	for {
+		const skipLog = 5
+		const doEvery = 2
+
+		nextS := s
+		var candidate tableEntry
+		for {
+			nextHash := hash(cv)
+			candidate = e.table[nextHash]
+			nextS = s + doEvery + (s-nextEmit)>>skipLog
+			if nextS > sLimit {
+				goto emitRemainder
+			}
+
+			now := load6432(src, nextS)
+			e.table[nextHash] = tableEntry{offset: s + e.cur, val: cv}
+			nextHash = hash(uint32(now))
+
+			offset := s - (candidate.offset - e.cur)
+			if offset < maxMatchOffset && cv == candidate.val {
+				e.table[nextHash] = tableEntry{offset: nextS + e.cur, val: uint32(now)}
+				break
+			}
+
+			// Do one right away...
+			cv = uint32(now)
+			s = nextS
+			nextS++
+			candidate = e.table[nextHash]
+			now >>= 8
+			e.table[nextHash] = tableEntry{offset: s + e.cur, val: cv}
+
+			offset = s - (candidate.offset - e.cur)
+			if offset < maxMatchOffset && cv == candidate.val {
+				e.table[nextHash] = tableEntry{offset: nextS + e.cur, val: uint32(now)}
+				break
+			}
+			cv = uint32(now)
+			s = nextS
+		}
+
+		// A 4-byte match has been found. We'll later see if more than 4 bytes
+		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
+		// them as literal bytes.
+		for {
+			// Invariant: we have a 4-byte match at s, and no need to emit any
+			// literal bytes prior to s.
+
+			// Extend the 4-byte match as long as possible.
+			t := candidate.offset - e.cur
+			l := e.matchlenLong(s+4, t+4, src) + 4
+
+			// Extend backwards
+			for t > 0 && s > nextEmit && src[t-1] == src[s-1] {
+				s--
+				t--
+				l++
+			}
+			if nextEmit < s {
+				emitLiteral(dst, src[nextEmit:s])
+			}
+
+			// Save the match found
+			dst.AddMatchLong(l, uint32(s-t-baseMatchOffset))
+			s += l
+			nextEmit = s
+			if nextS >= s {
+				s = nextS + 1
+			}
+			if s >= sLimit {
+				// Index first pair after match end.
+				if int(s+l+4) < len(src) {
+					cv := load3232(src, s)
+					e.table[hash(cv)] = tableEntry{offset: s + e.cur, val: cv}
+				}
+				goto emitRemainder
+			}
+
+			// We could immediately start working at s now, but to improve
+			// compression we first update the hash table at s-2 and at s. If
+			// another emitCopy is not our next move, also calculate nextHash
+			// at s+1. At least on GOARCH=amd64, these three hash calculations
+			// are faster as one load64 call (with some shifts) instead of
+			// three load32 calls.
+			x := load6432(src, s-2)
+			o := e.cur + s - 2
+			prevHash := hash(uint32(x))
+			e.table[prevHash] = tableEntry{offset: o, val: uint32(x)}
+			x >>= 16
+			currHash := hash(uint32(x))
+			candidate = e.table[currHash]
+			e.table[currHash] = tableEntry{offset: o + 2, val: uint32(x)}
+
+			offset := s - (candidate.offset - e.cur)
+			if offset > maxMatchOffset || uint32(x) != candidate.val {
+				cv = uint32(x >> 8)
+				s++
+				break
+			}
+		}
+	}
+
+emitRemainder:
+	if int(nextEmit) < len(src) {
+		// If nothing was added, don't encode literals.
+		if dst.n == 0 {
+			return
+		}
+		emitLiteral(dst, src[nextEmit:])
+	}
+}
diff --git a/vendor/github.com/klauspost/compress/flate/level2.go b/vendor/github.com/klauspost/compress/flate/level2.go
new file mode 100644
index 000000000..7c824431e
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/level2.go
@@ -0,0 +1,199 @@
+package flate
+
+// fastGen maintains the table for matches,
+// and the previous byte block for level 2.
+// This is the generic implementation.
+type fastEncL2 struct {
+	fastGen
+	table [bTableSize]tableEntry
+}
+
+// EncodeL2 uses a similar algorithm to level 1, but is capable
+// of matching across blocks giving better compression at a small slowdown.
+func (e *fastEncL2) Encode(dst *tokens, src []byte) {
+	const (
+		inputMargin            = 12 - 1
+		minNonLiteralBlockSize = 1 + 1 + inputMargin
+	)
+
+	// Protect against e.cur wraparound.
+	for e.cur >= bufferReset {
+		if len(e.hist) == 0 {
+			for i := range e.table[:] {
+				e.table[i] = tableEntry{}
+			}
+			e.cur = maxMatchOffset
+			break
+		}
+		// Shift down everything in the table that isn't already too far away.
+		minOff := e.cur + int32(len(e.hist)) - maxMatchOffset
+		for i := range e.table[:] {
+			v := e.table[i].offset
+			if v <= minOff {
+				v = 0
+			} else {
+				v = v - e.cur + maxMatchOffset
+			}
+			e.table[i].offset = v
+		}
+		e.cur = maxMatchOffset
+	}
+
+	s := e.addBlock(src)
+
+	// This check isn't in the Snappy implementation, but there, the caller
+	// instead of the callee handles this case.
+	if len(src) < minNonLiteralBlockSize {
+		// We do not fill the token table.
+		// This will be picked up by caller.
+		dst.n = uint16(len(src))
+		return
+	}
+
+	// Override src
+	src = e.hist
+	nextEmit := s
+
+	// sLimit is when to stop looking for offset/length copies. The inputMargin
+	// lets us use a fast path for emitLiteral in the main loop, while we are
+	// looking for copies.
+	sLimit := int32(len(src) - inputMargin)
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	cv := load3232(src, s)
+	for {
+		// When should we start skipping if we haven't found matches in a long while.
+		const skipLog = 5
+		const doEvery = 2
+
+		nextS := s
+		var candidate tableEntry
+		for {
+			nextHash := hash4u(cv, bTableBits)
+			s = nextS
+			nextS = s + doEvery + (s-nextEmit)>>skipLog
+			if nextS > sLimit {
+				goto emitRemainder
+			}
+			candidate = e.table[nextHash]
+			now := load6432(src, nextS)
+			e.table[nextHash] = tableEntry{offset: s + e.cur, val: cv}
+			nextHash = hash4u(uint32(now), bTableBits)
+
+			offset := s - (candidate.offset - e.cur)
+			if offset < maxMatchOffset && cv == candidate.val {
+				e.table[nextHash] = tableEntry{offset: nextS + e.cur, val: uint32(now)}
+				break
+			}
+
+			// Do one right away...
+			cv = uint32(now)
+			s = nextS
+			nextS++
+			candidate = e.table[nextHash]
+			now >>= 8
+			e.table[nextHash] = tableEntry{offset: s + e.cur, val: cv}
+
+			offset = s - (candidate.offset - e.cur)
+			if offset < maxMatchOffset && cv == candidate.val {
+				break
+			}
+			cv = uint32(now)
+		}
+
+		// A 4-byte match has been found. We'll later see if more than 4 bytes
+		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
+		// them as literal bytes.
+
+		// Call emitCopy, and then see if another emitCopy could be our next
+		// move. Repeat until we find no match for the input immediately after
+		// what was consumed by the last emitCopy call.
+		//
+		// If we exit this loop normally then we need to call emitLiteral next,
+		// though we don't yet know how big the literal will be. We handle that
+		// by proceeding to the next iteration of the main loop. We also can
+		// exit this loop via goto if we get close to exhausting the input.
+		for {
+			// Invariant: we have a 4-byte match at s, and no need to emit any
+			// literal bytes prior to s.
+
+			// Extend the 4-byte match as long as possible.
+			t := candidate.offset - e.cur
+			l := e.matchlenLong(s+4, t+4, src) + 4
+
+			// Extend backwards
+			for t > 0 && s > nextEmit && src[t-1] == src[s-1] {
+				s--
+				t--
+				l++
+			}
+			if nextEmit < s {
+				emitLiteral(dst, src[nextEmit:s])
+			}
+
+			dst.AddMatchLong(l, uint32(s-t-baseMatchOffset))
+			s += l
+			nextEmit = s
+			if nextS >= s {
+				s = nextS + 1
+			}
+
+			if s >= sLimit {
+				// Index first pair after match end.
+				if int(s+l+4) < len(src) {
+					cv := load3232(src, s)
+					e.table[hash4u(cv, bTableBits)] = tableEntry{offset: s + e.cur, val: cv}
+				}
+				goto emitRemainder
+			}
+
+			// Store every second hash in-between, but offset by 1.
+			for i := s - l + 2; i < s-5; i += 7 {
+				x := load6432(src, int32(i))
+				nextHash := hash4u(uint32(x), bTableBits)
+				e.table[nextHash] = tableEntry{offset: e.cur + i, val: uint32(x)}
+				// Skip one
+				x >>= 16
+				nextHash = hash4u(uint32(x), bTableBits)
+				e.table[nextHash] = tableEntry{offset: e.cur + i + 2, val: uint32(x)}
+				// Skip one
+				x >>= 16
+				nextHash = hash4u(uint32(x), bTableBits)
+				e.table[nextHash] = tableEntry{offset: e.cur + i + 4, val: uint32(x)}
+			}
+
+			// We could immediately start working at s now, but to improve
+			// compression we first update the hash table at s-2 to s. If
+			// another emitCopy is not our next move, also calculate nextHash
+			// at s+1. At least on GOARCH=amd64, these three hash calculations
+			// are faster as one load64 call (with some shifts) instead of
+			// three load32 calls.
+			x := load6432(src, s-2)
+			o := e.cur + s - 2
+			prevHash := hash4u(uint32(x), bTableBits)
+			prevHash2 := hash4u(uint32(x>>8), bTableBits)
+			e.table[prevHash] = tableEntry{offset: o, val: uint32(x)}
+			e.table[prevHash2] = tableEntry{offset: o + 1, val: uint32(x >> 8)}
+			currHash := hash4u(uint32(x>>16), bTableBits)
+			candidate = e.table[currHash]
+			e.table[currHash] = tableEntry{offset: o + 2, val: uint32(x >> 16)}
+
+			offset := s - (candidate.offset - e.cur)
+			if offset > maxMatchOffset || uint32(x>>16) != candidate.val {
+				cv = uint32(x >> 24)
+				s++
+				break
+			}
+		}
+	}
+
+emitRemainder:
+	if int(nextEmit) < len(src) {
+		// If nothing was added, don't encode literals.
+		if dst.n == 0 {
+			return
+		}
+
+		emitLiteral(dst, src[nextEmit:])
+	}
+}
diff --git a/vendor/github.com/klauspost/compress/flate/level3.go b/vendor/github.com/klauspost/compress/flate/level3.go
new file mode 100644
index 000000000..4153d24c9
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/level3.go
@@ -0,0 +1,225 @@
+package flate
+
+// fastEncL3
+type fastEncL3 struct {
+	fastGen
+	table [tableSize]tableEntryPrev
+}
+
+// Encode uses a similar algorithm to level 2, will check up to two candidates.
+func (e *fastEncL3) Encode(dst *tokens, src []byte) {
+	const (
+		inputMargin            = 8 - 1
+		minNonLiteralBlockSize = 1 + 1 + inputMargin
+	)
+
+	// Protect against e.cur wraparound.
+	for e.cur >= bufferReset {
+		if len(e.hist) == 0 {
+			for i := range e.table[:] {
+				e.table[i] = tableEntryPrev{}
+			}
+			e.cur = maxMatchOffset
+			break
+		}
+		// Shift down everything in the table that isn't already too far away.
+		minOff := e.cur + int32(len(e.hist)) - maxMatchOffset
+		for i := range e.table[:] {
+			v := e.table[i]
+			if v.Cur.offset <= minOff {
+				v.Cur.offset = 0
+			} else {
+				v.Cur.offset = v.Cur.offset - e.cur + maxMatchOffset
+			}
+			if v.Prev.offset <= minOff {
+				v.Prev.offset = 0
+			} else {
+				v.Prev.offset = v.Prev.offset - e.cur + maxMatchOffset
+			}
+			e.table[i] = v
+		}
+		e.cur = maxMatchOffset
+	}
+
+	s := e.addBlock(src)
+
+	// Skip if too small.
+	if len(src) < minNonLiteralBlockSize {
+		// We do not fill the token table.
+		// This will be picked up by caller.
+		dst.n = uint16(len(src))
+		return
+	}
+
+	// Override src
+	src = e.hist
+	nextEmit := s
+
+	// sLimit is when to stop looking for offset/length copies. The inputMargin
+	// lets us use a fast path for emitLiteral in the main loop, while we are
+	// looking for copies.
+	sLimit := int32(len(src) - inputMargin)
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	cv := load3232(src, s)
+	for {
+		const skipLog = 6
+		nextS := s
+		var candidate tableEntry
+		for {
+			nextHash := hash(cv)
+			s = nextS
+			nextS = s + 1 + (s-nextEmit)>>skipLog
+			if nextS > sLimit {
+				goto emitRemainder
+			}
+			candidates := e.table[nextHash]
+			now := load3232(src, nextS)
+			e.table[nextHash] = tableEntryPrev{Prev: candidates.Cur, Cur: tableEntry{offset: s + e.cur, val: cv}}
+
+			// Check both candidates
+			candidate = candidates.Cur
+			offset := s - (candidate.offset - e.cur)
+			if cv == candidate.val {
+				if offset > maxMatchOffset {
+					cv = now
+					// Previous will also be invalid, we have nothing.
+					continue
+				}
+				o2 := s - (candidates.Prev.offset - e.cur)
+				if cv != candidates.Prev.val || o2 > maxMatchOffset {
+					break
+				}
+				// Both match and are valid, pick longest.
+				l1, l2 := matchLen(src[s+4:], src[s-offset+4:]), matchLen(src[s+4:], src[s-o2+4:])
+				if l2 > l1 {
+					candidate = candidates.Prev
+				}
+				break
+			} else {
+				// We only check if value mismatches.
+				// Offset will always be invalid in other cases.
+				candidate = candidates.Prev
+				if cv == candidate.val {
+					offset := s - (candidate.offset - e.cur)
+					if offset <= maxMatchOffset {
+						break
+					}
+				}
+			}
+			cv = now
+		}
+
+		// Call emitCopy, and then see if another emitCopy could be our next
+		// move. Repeat until we find no match for the input immediately after
+		// what was consumed by the last emitCopy call.
+		//
+		// If we exit this loop normally then we need to call emitLiteral next,
+		// though we don't yet know how big the literal will be. We handle that
+		// by proceeding to the next iteration of the main loop. We also can
+		// exit this loop via goto if we get close to exhausting the input.
+		for {
+			// Invariant: we have a 4-byte match at s, and no need to emit any
+			// literal bytes prior to s.
+
+			// Extend the 4-byte match as long as possible.
+			//
+			t := candidate.offset - e.cur
+			l := e.matchlenLong(s+4, t+4, src) + 4
+
+			// Extend backwards
+			for t > 0 && s > nextEmit && src[t-1] == src[s-1] {
+				s--
+				t--
+				l++
+			}
+			if nextEmit < s {
+				emitLiteral(dst, src[nextEmit:s])
+			}
+
+			dst.AddMatchLong(l, uint32(s-t-baseMatchOffset))
+			s += l
+			nextEmit = s
+			if nextS >= s {
+				s = nextS + 1
+			}
+
+			if s >= sLimit {
+				t += l
+				// Index first pair after match end.
+				if int(t+4) < len(src) && t > 0 {
+					cv := load3232(src, t)
+					nextHash := hash(cv)
+					e.table[nextHash] = tableEntryPrev{
+						Prev: e.table[nextHash].Cur,
+						Cur:  tableEntry{offset: e.cur + t, val: cv},
+					}
+				}
+				goto emitRemainder
+			}
+
+			// We could immediately start working at s now, but to improve
+			// compression we first update the hash table at s-3 to s.
+			x := load6432(src, s-3)
+			prevHash := hash(uint32(x))
+			e.table[prevHash] = tableEntryPrev{
+				Prev: e.table[prevHash].Cur,
+				Cur:  tableEntry{offset: e.cur + s - 3, val: uint32(x)},
+			}
+			x >>= 8
+			prevHash = hash(uint32(x))
+
+			e.table[prevHash] = tableEntryPrev{
+				Prev: e.table[prevHash].Cur,
+				Cur:  tableEntry{offset: e.cur + s - 2, val: uint32(x)},
+			}
+			x >>= 8
+			prevHash = hash(uint32(x))
+
+			e.table[prevHash] = tableEntryPrev{
+				Prev: e.table[prevHash].Cur,
+				Cur:  tableEntry{offset: e.cur + s - 1, val: uint32(x)},
+			}
+			x >>= 8
+			currHash := hash(uint32(x))
+			candidates := e.table[currHash]
+			cv = uint32(x)
+			e.table[currHash] = tableEntryPrev{
+				Prev: candidates.Cur,
+				Cur:  tableEntry{offset: s + e.cur, val: cv},
+			}
+
+			// Check both candidates
+			candidate = candidates.Cur
+			if cv == candidate.val {
+				offset := s - (candidate.offset - e.cur)
+				if offset <= maxMatchOffset {
+					continue
+				}
+			} else {
+				// We only check if value mismatches.
+				// Offset will always be invalid in other cases.
+				candidate = candidates.Prev
+				if cv == candidate.val {
+					offset := s - (candidate.offset - e.cur)
+					if offset <= maxMatchOffset {
+						continue
+					}
+				}
+			}
+			cv = uint32(x >> 8)
+			s++
+			break
+		}
+	}
+
+emitRemainder:
+	if int(nextEmit) < len(src) {
+		// If nothing was added, don't encode literals.
+		if dst.n == 0 {
+			return
+		}
+
+		emitLiteral(dst, src[nextEmit:])
+	}
+}
diff --git a/vendor/github.com/klauspost/compress/flate/level4.go b/vendor/github.com/klauspost/compress/flate/level4.go
new file mode 100644
index 000000000..c689ac771
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/level4.go
@@ -0,0 +1,210 @@
+package flate
+
+import "fmt"
+
+type fastEncL4 struct {
+	fastGen
+	table  [tableSize]tableEntry
+	bTable [tableSize]tableEntry
+}
+
+func (e *fastEncL4) Encode(dst *tokens, src []byte) {
+	const (
+		inputMargin            = 12 - 1
+		minNonLiteralBlockSize = 1 + 1 + inputMargin
+	)
+
+	// Protect against e.cur wraparound.
+	for e.cur >= bufferReset {
+		if len(e.hist) == 0 {
+			for i := range e.table[:] {
+				e.table[i] = tableEntry{}
+			}
+			for i := range e.bTable[:] {
+				e.bTable[i] = tableEntry{}
+			}
+			e.cur = maxMatchOffset
+			break
+		}
+		// Shift down everything in the table that isn't already too far away.
+		minOff := e.cur + int32(len(e.hist)) - maxMatchOffset
+		for i := range e.table[:] {
+			v := e.table[i].offset
+			if v <= minOff {
+				v = 0
+			} else {
+				v = v - e.cur + maxMatchOffset
+			}
+			e.table[i].offset = v
+		}
+		for i := range e.bTable[:] {
+			v := e.bTable[i].offset
+			if v <= minOff {
+				v = 0
+			} else {
+				v = v - e.cur + maxMatchOffset
+			}
+			e.bTable[i].offset = v
+		}
+		e.cur = maxMatchOffset
+	}
+
+	s := e.addBlock(src)
+
+	// This check isn't in the Snappy implementation, but there, the caller
+	// instead of the callee handles this case.
+	if len(src) < minNonLiteralBlockSize {
+		// We do not fill the token table.
+		// This will be picked up by caller.
+		dst.n = uint16(len(src))
+		return
+	}
+
+	// Override src
+	src = e.hist
+	nextEmit := s
+
+	// sLimit is when to stop looking for offset/length copies. The inputMargin
+	// lets us use a fast path for emitLiteral in the main loop, while we are
+	// looking for copies.
+	sLimit := int32(len(src) - inputMargin)
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	cv := load6432(src, s)
+	for {
+		const skipLog = 6
+		const doEvery = 1
+
+		nextS := s
+		var t int32
+		for {
+			nextHashS := hash4x64(cv, tableBits)
+			nextHashL := hash7(cv, tableBits)
+
+			s = nextS
+			nextS = s + doEvery + (s-nextEmit)>>skipLog
+			if nextS > sLimit {
+				goto emitRemainder
+			}
+			// Fetch a short+long candidate
+			sCandidate := e.table[nextHashS]
+			lCandidate := e.bTable[nextHashL]
+			next := load6432(src, nextS)
+			entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
+			e.table[nextHashS] = entry
+			e.bTable[nextHashL] = entry
+
+			t = lCandidate.offset - e.cur
+			if s-t < maxMatchOffset && uint32(cv) == lCandidate.val {
+				// We got a long match. Use that.
+				break
+			}
+
+			t = sCandidate.offset - e.cur
+			if s-t < maxMatchOffset && uint32(cv) == sCandidate.val {
+				// Found a 4 match...
+				lCandidate = e.bTable[hash7(next, tableBits)]
+
+				// If the next long is a candidate, check if we should use that instead...
+				lOff := nextS - (lCandidate.offset - e.cur)
+				if lOff < maxMatchOffset && lCandidate.val == uint32(next) {
+					l1, l2 := matchLen(src[s+4:], src[t+4:]), matchLen(src[nextS+4:], src[nextS-lOff+4:])
+					if l2 > l1 {
+						s = nextS
+						t = lCandidate.offset - e.cur
+					}
+				}
+				break
+			}
+			cv = next
+		}
+
+		// A 4-byte match has been found. We'll later see if more than 4 bytes
+		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
+		// them as literal bytes.
+
+		// Extend the 4-byte match as long as possible.
+		l := e.matchlenLong(s+4, t+4, src) + 4
+
+		// Extend backwards
+		for t > 0 && s > nextEmit && src[t-1] == src[s-1] {
+			s--
+			t--
+			l++
+		}
+		if nextEmit < s {
+			emitLiteral(dst, src[nextEmit:s])
+		}
+		if false {
+			if t >= s {
+				panic("s-t")
+			}
+			if (s - t) > maxMatchOffset {
+				panic(fmt.Sprintln("mmo", t))
+			}
+			if l < baseMatchLength {
+				panic("bml")
+			}
+		}
+
+		dst.AddMatchLong(l, uint32(s-t-baseMatchOffset))
+		s += l
+		nextEmit = s
+		if nextS >= s {
+			s = nextS + 1
+		}
+
+		if s >= sLimit {
+			// Index first pair after match end.
+			if int(s+8) < len(src) {
+				cv := load6432(src, s)
+				e.table[hash4x64(cv, tableBits)] = tableEntry{offset: s + e.cur, val: uint32(cv)}
+				e.bTable[hash7(cv, tableBits)] = tableEntry{offset: s + e.cur, val: uint32(cv)}
+			}
+			goto emitRemainder
+		}
+
+		// Store every 3rd hash in-between
+		if true {
+			i := nextS
+			if i < s-1 {
+				cv := load6432(src, i)
+				t := tableEntry{offset: i + e.cur, val: uint32(cv)}
+				t2 := tableEntry{val: uint32(cv >> 8), offset: t.offset + 1}
+				e.bTable[hash7(cv, tableBits)] = t
+				e.bTable[hash7(cv>>8, tableBits)] = t2
+				e.table[hash4u(t2.val, tableBits)] = t2
+
+				i += 3
+				for ; i < s-1; i += 3 {
+					cv := load6432(src, i)
+					t := tableEntry{offset: i + e.cur, val: uint32(cv)}
+					t2 := tableEntry{val: uint32(cv >> 8), offset: t.offset + 1}
+					e.bTable[hash7(cv, tableBits)] = t
+					e.bTable[hash7(cv>>8, tableBits)] = t2
+					e.table[hash4u(t2.val, tableBits)] = t2
+				}
+			}
+		}
+
+		// We could immediately start working at s now, but to improve
+		// compression we first update the hash table at s-1 and at s.
+		x := load6432(src, s-1)
+		o := e.cur + s - 1
+		prevHashS := hash4x64(x, tableBits)
+		prevHashL := hash7(x, tableBits)
+		e.table[prevHashS] = tableEntry{offset: o, val: uint32(x)}
+		e.bTable[prevHashL] = tableEntry{offset: o, val: uint32(x)}
+		cv = x >> 8
+	}
+
+emitRemainder:
+	if int(nextEmit) < len(src) {
+		// If nothing was added, don't encode literals.
+		if dst.n == 0 {
+			return
+		}
+
+		emitLiteral(dst, src[nextEmit:])
+	}
+}
diff --git a/vendor/github.com/klauspost/compress/flate/level5.go b/vendor/github.com/klauspost/compress/flate/level5.go
new file mode 100644
index 000000000..14a235612
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/level5.go
@@ -0,0 +1,276 @@
+package flate
+
+import "fmt"
+
+type fastEncL5 struct {
+	fastGen
+	table  [tableSize]tableEntry
+	bTable [tableSize]tableEntryPrev
+}
+
+func (e *fastEncL5) Encode(dst *tokens, src []byte) {
+	const (
+		inputMargin            = 12 - 1
+		minNonLiteralBlockSize = 1 + 1 + inputMargin
+	)
+
+	// Protect against e.cur wraparound.
+	for e.cur >= bufferReset {
+		if len(e.hist) == 0 {
+			for i := range e.table[:] {
+				e.table[i] = tableEntry{}
+			}
+			for i := range e.bTable[:] {
+				e.bTable[i] = tableEntryPrev{}
+			}
+			e.cur = maxMatchOffset
+			break
+		}
+		// Shift down everything in the table that isn't already too far away.
+		minOff := e.cur + int32(len(e.hist)) - maxMatchOffset
+		for i := range e.table[:] {
+			v := e.table[i].offset
+			if v <= minOff {
+				v = 0
+			} else {
+				v = v - e.cur + maxMatchOffset
+			}
+			e.table[i].offset = v
+		}
+		for i := range e.bTable[:] {
+			v := e.bTable[i]
+			if v.Cur.offset <= minOff {
+				v.Cur.offset = 0
+				v.Prev.offset = 0
+			} else {
+				v.Cur.offset = v.Cur.offset - e.cur + maxMatchOffset
+				if v.Prev.offset <= minOff {
+					v.Prev.offset = 0
+				} else {
+					v.Prev.offset = v.Prev.offset - e.cur + maxMatchOffset
+				}
+			}
+			e.bTable[i] = v
+		}
+		e.cur = maxMatchOffset
+	}
+
+	s := e.addBlock(src)
+
+	// This check isn't in the Snappy implementation, but there, the caller
+	// instead of the callee handles this case.
+	if len(src) < minNonLiteralBlockSize {
+		// We do not fill the token table.
+		// This will be picked up by caller.
+		dst.n = uint16(len(src))
+		return
+	}
+
+	// Override src
+	src = e.hist
+	nextEmit := s
+
+	// sLimit is when to stop looking for offset/length copies. The inputMargin
+	// lets us use a fast path for emitLiteral in the main loop, while we are
+	// looking for copies.
+	sLimit := int32(len(src) - inputMargin)
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	cv := load6432(src, s)
+	for {
+		const skipLog = 6
+		const doEvery = 1
+
+		nextS := s
+		var l int32
+		var t int32
+		for {
+			nextHashS := hash4x64(cv, tableBits)
+			nextHashL := hash7(cv, tableBits)
+
+			s = nextS
+			nextS = s + doEvery + (s-nextEmit)>>skipLog
+			if nextS > sLimit {
+				goto emitRemainder
+			}
+			// Fetch a short+long candidate
+			sCandidate := e.table[nextHashS]
+			lCandidate := e.bTable[nextHashL]
+			next := load6432(src, nextS)
+			entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
+			e.table[nextHashS] = entry
+			eLong := &e.bTable[nextHashL]
+			eLong.Cur, eLong.Prev = entry, eLong.Cur
+
+			nextHashS = hash4x64(next, tableBits)
+			nextHashL = hash7(next, tableBits)
+
+			t = lCandidate.Cur.offset - e.cur
+			if s-t < maxMatchOffset {
+				if uint32(cv) == lCandidate.Cur.val {
+					// Store the next match
+					e.table[nextHashS] = tableEntry{offset: nextS + e.cur, val: uint32(next)}
+					eLong := &e.bTable[nextHashL]
+					eLong.Cur, eLong.Prev = tableEntry{offset: nextS + e.cur, val: uint32(next)}, eLong.Cur
+
+					t2 := lCandidate.Prev.offset - e.cur
+					if s-t2 < maxMatchOffset && uint32(cv) == lCandidate.Prev.val {
+						l = e.matchlen(s+4, t+4, src) + 4
+						ml1 := e.matchlen(s+4, t2+4, src) + 4
+						if ml1 > l {
+							t = t2
+							l = ml1
+							break
+						}
+					}
+					break
+				}
+				t = lCandidate.Prev.offset - e.cur
+				if s-t < maxMatchOffset && uint32(cv) == lCandidate.Prev.val {
+					// Store the next match
+					e.table[nextHashS] = tableEntry{offset: nextS + e.cur, val: uint32(next)}
+					eLong := &e.bTable[nextHashL]
+					eLong.Cur, eLong.Prev = tableEntry{offset: nextS + e.cur, val: uint32(next)}, eLong.Cur
+					break
+				}
+			}
+
+			t = sCandidate.offset - e.cur
+			if s-t < maxMatchOffset && uint32(cv) == sCandidate.val {
+				// Found a 4 match...
+				l = e.matchlen(s+4, t+4, src) + 4
+				lCandidate = e.bTable[nextHashL]
+				// Store the next match
+
+				e.table[nextHashS] = tableEntry{offset: nextS + e.cur, val: uint32(next)}
+				eLong := &e.bTable[nextHashL]
+				eLong.Cur, eLong.Prev = tableEntry{offset: nextS + e.cur, val: uint32(next)}, eLong.Cur
+
+				// If the next long is a candidate, use that...
+				t2 := lCandidate.Cur.offset - e.cur
+				if nextS-t2 < maxMatchOffset {
+					if lCandidate.Cur.val == uint32(next) {
+						ml := e.matchlen(nextS+4, t2+4, src) + 4
+						if ml > l {
+							t = t2
+							s = nextS
+							l = ml
+							break
+						}
+					}
+					// If the previous long is a candidate, use that...
+					t2 = lCandidate.Prev.offset - e.cur
+					if nextS-t2 < maxMatchOffset && lCandidate.Prev.val == uint32(next) {
+						ml := e.matchlen(nextS+4, t2+4, src) + 4
+						if ml > l {
+							t = t2
+							s = nextS
+							l = ml
+							break
+						}
+					}
+				}
+				break
+			}
+			cv = next
+		}
+
+		// A 4-byte match has been found. We'll later see if more than 4 bytes
+		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
+		// them as literal bytes.
+
+		// Extend the 4-byte match as long as possible.
+		if l == 0 {
+			l = e.matchlenLong(s+4, t+4, src) + 4
+		} else if l == maxMatchLength {
+			l += e.matchlenLong(s+l, t+l, src)
+		}
+		// Extend backwards
+		for t > 0 && s > nextEmit && src[t-1] == src[s-1] {
+			s--
+			t--
+			l++
+		}
+		if nextEmit < s {
+			emitLiteral(dst, src[nextEmit:s])
+		}
+		if false {
+			if t >= s {
+				panic(fmt.Sprintln("s-t", s, t))
+			}
+			if (s - t) > maxMatchOffset {
+				panic(fmt.Sprintln("mmo", s-t))
+			}
+			if l < baseMatchLength {
+				panic("bml")
+			}
+		}
+
+		dst.AddMatchLong(l, uint32(s-t-baseMatchOffset))
+		s += l
+		nextEmit = s
+		if nextS >= s {
+			s = nextS + 1
+		}
+
+		if s >= sLimit {
+			goto emitRemainder
+		}
+
+		// Store every 3rd hash in-between.
+		if true {
+			const hashEvery = 3
+			i := s - l + 1
+			if i < s-1 {
+				cv := load6432(src, i)
+				t := tableEntry{offset: i + e.cur, val: uint32(cv)}
+				e.table[hash4x64(cv, tableBits)] = t
+				eLong := &e.bTable[hash7(cv, tableBits)]
+				eLong.Cur, eLong.Prev = t, eLong.Cur
+
+				// Do an long at i+1
+				cv >>= 8
+				t = tableEntry{offset: t.offset + 1, val: uint32(cv)}
+				eLong = &e.bTable[hash7(cv, tableBits)]
+				eLong.Cur, eLong.Prev = t, eLong.Cur
+
+				// We only have enough bits for a short entry at i+2
+				cv >>= 8
+				t = tableEntry{offset: t.offset + 1, val: uint32(cv)}
+				e.table[hash4x64(cv, tableBits)] = t
+
+				// Skip one - otherwise we risk hitting 's'
+				i += 4
+				for ; i < s-1; i += hashEvery {
+					cv := load6432(src, i)
+					t := tableEntry{offset: i + e.cur, val: uint32(cv)}
+					t2 := tableEntry{offset: t.offset + 1, val: uint32(cv >> 8)}
+					eLong := &e.bTable[hash7(cv, tableBits)]
+					eLong.Cur, eLong.Prev = t, eLong.Cur
+					e.table[hash4u(t2.val, tableBits)] = t2
+				}
+			}
+		}
+
+		// We could immediately start working at s now, but to improve
+		// compression we first update the hash table at s-1 and at s.
+		x := load6432(src, s-1)
+		o := e.cur + s - 1
+		prevHashS := hash4x64(x, tableBits)
+		prevHashL := hash7(x, tableBits)
+		e.table[prevHashS] = tableEntry{offset: o, val: uint32(x)}
+		eLong := &e.bTable[prevHashL]
+		eLong.Cur, eLong.Prev = tableEntry{offset: o, val: uint32(x)}, eLong.Cur
+		cv = x >> 8
+	}
+
+emitRemainder:
+	if int(nextEmit) < len(src) {
+		// If nothing was added, don't encode literals.
+		if dst.n == 0 {
+			return
+		}
+
+		emitLiteral(dst, src[nextEmit:])
+	}
+}
diff --git a/vendor/github.com/klauspost/compress/flate/level6.go b/vendor/github.com/klauspost/compress/flate/level6.go
new file mode 100644
index 000000000..cad0c7df7
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/level6.go
@@ -0,0 +1,279 @@
+package flate
+
+import "fmt"
+
+type fastEncL6 struct {
+	fastGen
+	table  [tableSize]tableEntry
+	bTable [tableSize]tableEntryPrev
+}
+
+func (e *fastEncL6) Encode(dst *tokens, src []byte) {
+	const (
+		inputMargin            = 12 - 1
+		minNonLiteralBlockSize = 1 + 1 + inputMargin
+	)
+
+	// Protect against e.cur wraparound.
+	for e.cur >= bufferReset {
+		if len(e.hist) == 0 {
+			for i := range e.table[:] {
+				e.table[i] = tableEntry{}
+			}
+			for i := range e.bTable[:] {
+				e.bTable[i] = tableEntryPrev{}
+			}
+			e.cur = maxMatchOffset
+			break
+		}
+		// Shift down everything in the table that isn't already too far away.
+		minOff := e.cur + int32(len(e.hist)) - maxMatchOffset
+		for i := range e.table[:] {
+			v := e.table[i].offset
+			if v <= minOff {
+				v = 0
+			} else {
+				v = v - e.cur + maxMatchOffset
+			}
+			e.table[i].offset = v
+		}
+		for i := range e.bTable[:] {
+			v := e.bTable[i]
+			if v.Cur.offset <= minOff {
+				v.Cur.offset = 0
+				v.Prev.offset = 0
+			} else {
+				v.Cur.offset = v.Cur.offset - e.cur + maxMatchOffset
+				if v.Prev.offset <= minOff {
+					v.Prev.offset = 0
+				} else {
+					v.Prev.offset = v.Prev.offset - e.cur + maxMatchOffset
+				}
+			}
+			e.bTable[i] = v
+		}
+		e.cur = maxMatchOffset
+	}
+
+	s := e.addBlock(src)
+
+	// This check isn't in the Snappy implementation, but there, the caller
+	// instead of the callee handles this case.
+	if len(src) < minNonLiteralBlockSize {
+		// We do not fill the token table.
+		// This will be picked up by caller.
+		dst.n = uint16(len(src))
+		return
+	}
+
+	// Override src
+	src = e.hist
+	nextEmit := s
+
+	// sLimit is when to stop looking for offset/length copies. The inputMargin
+	// lets us use a fast path for emitLiteral in the main loop, while we are
+	// looking for copies.
+	sLimit := int32(len(src) - inputMargin)
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	cv := load6432(src, s)
+	// Repeat MUST be > 1 and within range
+	repeat := int32(1)
+	for {
+		const skipLog = 7
+		const doEvery = 1
+
+		nextS := s
+		var l int32
+		var t int32
+		for {
+			nextHashS := hash4x64(cv, tableBits)
+			nextHashL := hash7(cv, tableBits)
+			s = nextS
+			nextS = s + doEvery + (s-nextEmit)>>skipLog
+			if nextS > sLimit {
+				goto emitRemainder
+			}
+			// Fetch a short+long candidate
+			sCandidate := e.table[nextHashS]
+			lCandidate := e.bTable[nextHashL]
+			next := load6432(src, nextS)
+			entry := tableEntry{offset: s + e.cur, val: uint32(cv)}
+			e.table[nextHashS] = entry
+			eLong := &e.bTable[nextHashL]
+			eLong.Cur, eLong.Prev = entry, eLong.Cur
+
+			// Calculate hashes of 'next'
+			nextHashS = hash4x64(next, tableBits)
+			nextHashL = hash7(next, tableBits)
+
+			t = lCandidate.Cur.offset - e.cur
+			if s-t < maxMatchOffset {
+				if uint32(cv) == lCandidate.Cur.val {
+					// Long candidate matches at least 4 bytes.
+
+					// Store the next match
+					e.table[nextHashS] = tableEntry{offset: nextS + e.cur, val: uint32(next)}
+					eLong := &e.bTable[nextHashL]
+					eLong.Cur, eLong.Prev = tableEntry{offset: nextS + e.cur, val: uint32(next)}, eLong.Cur
+
+					// Check the previous long candidate as well.
+					t2 := lCandidate.Prev.offset - e.cur
+					if s-t2 < maxMatchOffset && uint32(cv) == lCandidate.Prev.val {
+						l = e.matchlen(s+4, t+4, src) + 4
+						ml1 := e.matchlen(s+4, t2+4, src) + 4
+						if ml1 > l {
+							t = t2
+							l = ml1
+							break
+						}
+					}
+					break
+				}
+				// Current value did not match, but check if previous long value does.
+				t = lCandidate.Prev.offset - e.cur
+				if s-t < maxMatchOffset && uint32(cv) == lCandidate.Prev.val {
+					// Store the next match
+					e.table[nextHashS] = tableEntry{offset: nextS + e.cur, val: uint32(next)}
+					eLong := &e.bTable[nextHashL]
+					eLong.Cur, eLong.Prev = tableEntry{offset: nextS + e.cur, val: uint32(next)}, eLong.Cur
+					break
+				}
+			}
+
+			t = sCandidate.offset - e.cur
+			if s-t < maxMatchOffset && uint32(cv) == sCandidate.val {
+				// Found a 4 match...
+				l = e.matchlen(s+4, t+4, src) + 4
+
+				// Look up next long candidate (at nextS)
+				lCandidate = e.bTable[nextHashL]
+
+				// Store the next match
+				e.table[nextHashS] = tableEntry{offset: nextS + e.cur, val: uint32(next)}
+				eLong := &e.bTable[nextHashL]
+				eLong.Cur, eLong.Prev = tableEntry{offset: nextS + e.cur, val: uint32(next)}, eLong.Cur
+
+				// Check repeat at s + repOff
+				const repOff = 1
+				t2 := s - repeat + repOff
+				if load3232(src, t2) == uint32(cv>>(8*repOff)) {
+					ml := e.matchlen(s+4+repOff, t2+4, src) + 4
+					if ml > l {
+						t = t2
+						l = ml
+						s += repOff
+						// Not worth checking more.
+						break
+					}
+				}
+
+				// If the next long is a candidate, use that...
+				t2 = lCandidate.Cur.offset - e.cur
+				if nextS-t2 < maxMatchOffset {
+					if lCandidate.Cur.val == uint32(next) {
+						ml := e.matchlen(nextS+4, t2+4, src) + 4
+						if ml > l {
+							t = t2
+							s = nextS
+							l = ml
+							// This is ok, but check previous as well.
+						}
+					}
+					// If the previous long is a candidate, use that...
+					t2 = lCandidate.Prev.offset - e.cur
+					if nextS-t2 < maxMatchOffset && lCandidate.Prev.val == uint32(next) {
+						ml := e.matchlen(nextS+4, t2+4, src) + 4
+						if ml > l {
+							t = t2
+							s = nextS
+							l = ml
+							break
+						}
+					}
+				}
+				break
+			}
+			cv = next
+		}
+
+		// A 4-byte match has been found. We'll later see if more than 4 bytes
+		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
+		// them as literal bytes.
+
+		// Extend the 4-byte match as long as possible.
+		if l == 0 {
+			l = e.matchlenLong(s+4, t+4, src) + 4
+		} else if l == maxMatchLength {
+			l += e.matchlenLong(s+l, t+l, src)
+		}
+
+		// Extend backwards
+		for t > 0 && s > nextEmit && src[t-1] == src[s-1] {
+			s--
+			t--
+			l++
+		}
+		if nextEmit < s {
+			emitLiteral(dst, src[nextEmit:s])
+		}
+		if false {
+			if t >= s {
+				panic(fmt.Sprintln("s-t", s, t))
+			}
+			if (s - t) > maxMatchOffset {
+				panic(fmt.Sprintln("mmo", s-t))
+			}
+			if l < baseMatchLength {
+				panic("bml")
+			}
+		}
+
+		dst.AddMatchLong(l, uint32(s-t-baseMatchOffset))
+		repeat = s - t
+		s += l
+		nextEmit = s
+		if nextS >= s {
+			s = nextS + 1
+		}
+
+		if s >= sLimit {
+			// Index after match end.
+			for i := nextS + 1; i < int32(len(src))-8; i += 2 {
+				cv := load6432(src, i)
+				e.table[hash4x64(cv, tableBits)] = tableEntry{offset: i + e.cur, val: uint32(cv)}
+				eLong := &e.bTable[hash7(cv, tableBits)]
+				eLong.Cur, eLong.Prev = tableEntry{offset: i + e.cur, val: uint32(cv)}, eLong.Cur
+			}
+			goto emitRemainder
+		}
+
+		// Store every long hash in-between and every second short.
+		if true {
+			for i := nextS + 1; i < s-1; i += 2 {
+				cv := load6432(src, i)
+				t := tableEntry{offset: i + e.cur, val: uint32(cv)}
+				t2 := tableEntry{offset: t.offset + 1, val: uint32(cv >> 8)}
+				eLong := &e.bTable[hash7(cv, tableBits)]
+				eLong2 := &e.bTable[hash7(cv>>8, tableBits)]
+				e.table[hash4x64(cv, tableBits)] = t
+				eLong.Cur, eLong.Prev = t, eLong.Cur
+				eLong2.Cur, eLong2.Prev = t2, eLong2.Cur
+			}
+		}
+
+		// We could immediately start working at s now, but to improve
+		// compression we first update the hash table at s-1 and at s.
+		cv = load6432(src, s)
+	}
+
+emitRemainder:
+	if int(nextEmit) < len(src) {
+		// If nothing was added, don't encode literals.
+		if dst.n == 0 {
+			return
+		}
+
+		emitLiteral(dst, src[nextEmit:])
+	}
+}
diff --git a/vendor/github.com/klauspost/compress/flate/reverse_bits.go b/vendor/github.com/klauspost/compress/flate/reverse_bits.go
deleted file mode 100644
index c1a02720d..000000000
--- a/vendor/github.com/klauspost/compress/flate/reverse_bits.go
+++ /dev/null
@@ -1,48 +0,0 @@
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package flate
-
-var reverseByte = [256]byte{
-	0x00, 0x80, 0x40, 0xc0, 0x20, 0xa0, 0x60, 0xe0,
-	0x10, 0x90, 0x50, 0xd0, 0x30, 0xb0, 0x70, 0xf0,
-	0x08, 0x88, 0x48, 0xc8, 0x28, 0xa8, 0x68, 0xe8,
-	0x18, 0x98, 0x58, 0xd8, 0x38, 0xb8, 0x78, 0xf8,
-	0x04, 0x84, 0x44, 0xc4, 0x24, 0xa4, 0x64, 0xe4,
-	0x14, 0x94, 0x54, 0xd4, 0x34, 0xb4, 0x74, 0xf4,
-	0x0c, 0x8c, 0x4c, 0xcc, 0x2c, 0xac, 0x6c, 0xec,
-	0x1c, 0x9c, 0x5c, 0xdc, 0x3c, 0xbc, 0x7c, 0xfc,
-	0x02, 0x82, 0x42, 0xc2, 0x22, 0xa2, 0x62, 0xe2,
-	0x12, 0x92, 0x52, 0xd2, 0x32, 0xb2, 0x72, 0xf2,
-	0x0a, 0x8a, 0x4a, 0xca, 0x2a, 0xaa, 0x6a, 0xea,
-	0x1a, 0x9a, 0x5a, 0xda, 0x3a, 0xba, 0x7a, 0xfa,
-	0x06, 0x86, 0x46, 0xc6, 0x26, 0xa6, 0x66, 0xe6,
-	0x16, 0x96, 0x56, 0xd6, 0x36, 0xb6, 0x76, 0xf6,
-	0x0e, 0x8e, 0x4e, 0xce, 0x2e, 0xae, 0x6e, 0xee,
-	0x1e, 0x9e, 0x5e, 0xde, 0x3e, 0xbe, 0x7e, 0xfe,
-	0x01, 0x81, 0x41, 0xc1, 0x21, 0xa1, 0x61, 0xe1,
-	0x11, 0x91, 0x51, 0xd1, 0x31, 0xb1, 0x71, 0xf1,
-	0x09, 0x89, 0x49, 0xc9, 0x29, 0xa9, 0x69, 0xe9,
-	0x19, 0x99, 0x59, 0xd9, 0x39, 0xb9, 0x79, 0xf9,
-	0x05, 0x85, 0x45, 0xc5, 0x25, 0xa5, 0x65, 0xe5,
-	0x15, 0x95, 0x55, 0xd5, 0x35, 0xb5, 0x75, 0xf5,
-	0x0d, 0x8d, 0x4d, 0xcd, 0x2d, 0xad, 0x6d, 0xed,
-	0x1d, 0x9d, 0x5d, 0xdd, 0x3d, 0xbd, 0x7d, 0xfd,
-	0x03, 0x83, 0x43, 0xc3, 0x23, 0xa3, 0x63, 0xe3,
-	0x13, 0x93, 0x53, 0xd3, 0x33, 0xb3, 0x73, 0xf3,
-	0x0b, 0x8b, 0x4b, 0xcb, 0x2b, 0xab, 0x6b, 0xeb,
-	0x1b, 0x9b, 0x5b, 0xdb, 0x3b, 0xbb, 0x7b, 0xfb,
-	0x07, 0x87, 0x47, 0xc7, 0x27, 0xa7, 0x67, 0xe7,
-	0x17, 0x97, 0x57, 0xd7, 0x37, 0xb7, 0x77, 0xf7,
-	0x0f, 0x8f, 0x4f, 0xcf, 0x2f, 0xaf, 0x6f, 0xef,
-	0x1f, 0x9f, 0x5f, 0xdf, 0x3f, 0xbf, 0x7f, 0xff,
-}
-
-func reverseUint16(v uint16) uint16 {
-	return uint16(reverseByte[v>>8]) | uint16(reverseByte[v&0xFF])<<8
-}
-
-func reverseBits(number uint16, bitLength byte) uint16 {
-	return reverseUint16(number << uint8(16-bitLength))
-}
diff --git a/vendor/github.com/klauspost/compress/flate/snappy.go b/vendor/github.com/klauspost/compress/flate/snappy.go
deleted file mode 100644
index aebebd524..000000000
--- a/vendor/github.com/klauspost/compress/flate/snappy.go
+++ /dev/null
@@ -1,900 +0,0 @@
-// Copyright 2011 The Snappy-Go Authors. All rights reserved.
-// Modified for deflate by Klaus Post (c) 2015.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package flate
-
-// emitLiteral writes a literal chunk and returns the number of bytes written.
-func emitLiteral(dst *tokens, lit []byte) {
-	ol := int(dst.n)
-	for i, v := range lit {
-		dst.tokens[(i+ol)&maxStoreBlockSize] = token(v)
-	}
-	dst.n += uint16(len(lit))
-}
-
-// emitCopy writes a copy chunk and returns the number of bytes written.
-func emitCopy(dst *tokens, offset, length int) {
-	dst.tokens[dst.n] = matchToken(uint32(length-3), uint32(offset-minOffsetSize))
-	dst.n++
-}
-
-type fastEnc interface {
-	Encode(dst *tokens, src []byte)
-	Reset()
-}
-
-func newFastEnc(level int) fastEnc {
-	switch level {
-	case 1:
-		return &snappyL1{}
-	case 2:
-		return &snappyL2{snappyGen: snappyGen{cur: maxStoreBlockSize, prev: make([]byte, 0, maxStoreBlockSize)}}
-	case 3:
-		return &snappyL3{snappyGen: snappyGen{cur: maxStoreBlockSize, prev: make([]byte, 0, maxStoreBlockSize)}}
-	case 4:
-		return &snappyL4{snappyL3{snappyGen: snappyGen{cur: maxStoreBlockSize, prev: make([]byte, 0, maxStoreBlockSize)}}}
-	default:
-		panic("invalid level specified")
-	}
-}
-
-const (
-	tableBits       = 14             // Bits used in the table
-	tableSize       = 1 << tableBits // Size of the table
-	tableMask       = tableSize - 1  // Mask for table indices. Redundant, but can eliminate bounds checks.
-	tableShift      = 32 - tableBits // Right-shift to get the tableBits most significant bits of a uint32.
-	baseMatchOffset = 1              // The smallest match offset
-	baseMatchLength = 3              // The smallest match length per the RFC section 3.2.5
-	maxMatchOffset  = 1 << 15        // The largest match offset
-)
-
-func load32(b []byte, i int) uint32 {
-	b = b[i : i+4 : len(b)] // Help the compiler eliminate bounds checks on the next line.
-	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
-}
-
-func load64(b []byte, i int) uint64 {
-	b = b[i : i+8 : len(b)] // Help the compiler eliminate bounds checks on the next line.
-	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
-		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
-}
-
-func hash(u uint32) uint32 {
-	return (u * 0x1e35a7bd) >> tableShift
-}
-
-// snappyL1 encapsulates level 1 compression
-type snappyL1 struct{}
-
-func (e *snappyL1) Reset() {}
-
-func (e *snappyL1) Encode(dst *tokens, src []byte) {
-	const (
-		inputMargin            = 16 - 1
-		minNonLiteralBlockSize = 1 + 1 + inputMargin
-	)
-
-	// This check isn't in the Snappy implementation, but there, the caller
-	// instead of the callee handles this case.
-	if len(src) < minNonLiteralBlockSize {
-		// We do not fill the token table.
-		// This will be picked up by caller.
-		dst.n = uint16(len(src))
-		return
-	}
-
-	// Initialize the hash table.
-	//
-	// The table element type is uint16, as s < sLimit and sLimit < len(src)
-	// and len(src) <= maxStoreBlockSize and maxStoreBlockSize == 65535.
-	var table [tableSize]uint16
-
-	// sLimit is when to stop looking for offset/length copies. The inputMargin
-	// lets us use a fast path for emitLiteral in the main loop, while we are
-	// looking for copies.
-	sLimit := len(src) - inputMargin
-
-	// nextEmit is where in src the next emitLiteral should start from.
-	nextEmit := 0
-
-	// The encoded form must start with a literal, as there are no previous
-	// bytes to copy, so we start looking for hash matches at s == 1.
-	s := 1
-	nextHash := hash(load32(src, s))
-
-	for {
-		// Copied from the C++ snappy implementation:
-		//
-		// Heuristic match skipping: If 32 bytes are scanned with no matches
-		// found, start looking only at every other byte. If 32 more bytes are
-		// scanned (or skipped), look at every third byte, etc.. When a match
-		// is found, immediately go back to looking at every byte. This is a
-		// small loss (~5% performance, ~0.1% density) for compressible data
-		// due to more bookkeeping, but for non-compressible data (such as
-		// JPEG) it's a huge win since the compressor quickly "realizes" the
-		// data is incompressible and doesn't bother looking for matches
-		// everywhere.
-		//
-		// The "skip" variable keeps track of how many bytes there are since
-		// the last match; dividing it by 32 (ie. right-shifting by five) gives
-		// the number of bytes to move ahead for each iteration.
-		skip := 32
-
-		nextS := s
-		candidate := 0
-		for {
-			s = nextS
-			bytesBetweenHashLookups := skip >> 5
-			nextS = s + bytesBetweenHashLookups
-			skip += bytesBetweenHashLookups
-			if nextS > sLimit {
-				goto emitRemainder
-			}
-			candidate = int(table[nextHash&tableMask])
-			table[nextHash&tableMask] = uint16(s)
-			nextHash = hash(load32(src, nextS))
-			if s-candidate <= maxMatchOffset && load32(src, s) == load32(src, candidate) {
-				break
-			}
-		}
-
-		// A 4-byte match has been found. We'll later see if more than 4 bytes
-		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
-		// them as literal bytes.
-		emitLiteral(dst, src[nextEmit:s])
-
-		// Call emitCopy, and then see if another emitCopy could be our next
-		// move. Repeat until we find no match for the input immediately after
-		// what was consumed by the last emitCopy call.
-		//
-		// If we exit this loop normally then we need to call emitLiteral next,
-		// though we don't yet know how big the literal will be. We handle that
-		// by proceeding to the next iteration of the main loop. We also can
-		// exit this loop via goto if we get close to exhausting the input.
-		for {
-			// Invariant: we have a 4-byte match at s, and no need to emit any
-			// literal bytes prior to s.
-			base := s
-
-			// Extend the 4-byte match as long as possible.
-			//
-			// This is an inlined version of Snappy's:
-			//	s = extendMatch(src, candidate+4, s+4)
-			s += 4
-			s1 := base + maxMatchLength
-			if s1 > len(src) {
-				s1 = len(src)
-			}
-			a := src[s:s1]
-			b := src[candidate+4:]
-			b = b[:len(a)]
-			l := len(a)
-			for i := range a {
-				if a[i] != b[i] {
-					l = i
-					break
-				}
-			}
-			s += l
-
-			// matchToken is flate's equivalent of Snappy's emitCopy.
-			dst.tokens[dst.n] = matchToken(uint32(s-base-baseMatchLength), uint32(base-candidate-baseMatchOffset))
-			dst.n++
-			nextEmit = s
-			if s >= sLimit {
-				goto emitRemainder
-			}
-
-			// We could immediately start working at s now, but to improve
-			// compression we first update the hash table at s-1 and at s. If
-			// another emitCopy is not our next move, also calculate nextHash
-			// at s+1. At least on GOARCH=amd64, these three hash calculations
-			// are faster as one load64 call (with some shifts) instead of
-			// three load32 calls.
-			x := load64(src, s-1)
-			prevHash := hash(uint32(x >> 0))
-			table[prevHash&tableMask] = uint16(s - 1)
-			currHash := hash(uint32(x >> 8))
-			candidate = int(table[currHash&tableMask])
-			table[currHash&tableMask] = uint16(s)
-			if s-candidate > maxMatchOffset || uint32(x>>8) != load32(src, candidate) {
-				nextHash = hash(uint32(x >> 16))
-				s++
-				break
-			}
-		}
-	}
-
-emitRemainder:
-	if nextEmit < len(src) {
-		emitLiteral(dst, src[nextEmit:])
-	}
-}
-
-type tableEntry struct {
-	val    uint32
-	offset int32
-}
-
-func load3232(b []byte, i int32) uint32 {
-	b = b[i : i+4 : len(b)] // Help the compiler eliminate bounds checks on the next line.
-	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
-}
-
-func load6432(b []byte, i int32) uint64 {
-	b = b[i : i+8 : len(b)] // Help the compiler eliminate bounds checks on the next line.
-	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
-		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
-}
-
-// snappyGen maintains the table for matches,
-// and the previous byte block for level 2.
-// This is the generic implementation.
-type snappyGen struct {
-	prev []byte
-	cur  int32
-}
-
-// snappyGen maintains the table for matches,
-// and the previous byte block for level 2.
-// This is the generic implementation.
-type snappyL2 struct {
-	snappyGen
-	table [tableSize]tableEntry
-}
-
-// EncodeL2 uses a similar algorithm to level 1, but is capable
-// of matching across blocks giving better compression at a small slowdown.
-func (e *snappyL2) Encode(dst *tokens, src []byte) {
-	const (
-		inputMargin            = 8 - 1
-		minNonLiteralBlockSize = 1 + 1 + inputMargin
-	)
-
-	// Protect against e.cur wraparound.
-	if e.cur > 1<<30 {
-		for i := range e.table[:] {
-			e.table[i] = tableEntry{}
-		}
-		e.cur = maxStoreBlockSize
-	}
-
-	// This check isn't in the Snappy implementation, but there, the caller
-	// instead of the callee handles this case.
-	if len(src) < minNonLiteralBlockSize {
-		// We do not fill the token table.
-		// This will be picked up by caller.
-		dst.n = uint16(len(src))
-		e.cur += maxStoreBlockSize
-		e.prev = e.prev[:0]
-		return
-	}
-
-	// sLimit is when to stop looking for offset/length copies. The inputMargin
-	// lets us use a fast path for emitLiteral in the main loop, while we are
-	// looking for copies.
-	sLimit := int32(len(src) - inputMargin)
-
-	// nextEmit is where in src the next emitLiteral should start from.
-	nextEmit := int32(0)
-	s := int32(0)
-	cv := load3232(src, s)
-	nextHash := hash(cv)
-
-	for {
-		// Copied from the C++ snappy implementation:
-		//
-		// Heuristic match skipping: If 32 bytes are scanned with no matches
-		// found, start looking only at every other byte. If 32 more bytes are
-		// scanned (or skipped), look at every third byte, etc.. When a match
-		// is found, immediately go back to looking at every byte. This is a
-		// small loss (~5% performance, ~0.1% density) for compressible data
-		// due to more bookkeeping, but for non-compressible data (such as
-		// JPEG) it's a huge win since the compressor quickly "realizes" the
-		// data is incompressible and doesn't bother looking for matches
-		// everywhere.
-		//
-		// The "skip" variable keeps track of how many bytes there are since
-		// the last match; dividing it by 32 (ie. right-shifting by five) gives
-		// the number of bytes to move ahead for each iteration.
-		skip := int32(32)
-
-		nextS := s
-		var candidate tableEntry
-		for {
-			s = nextS
-			bytesBetweenHashLookups := skip >> 5
-			nextS = s + bytesBetweenHashLookups
-			skip += bytesBetweenHashLookups
-			if nextS > sLimit {
-				goto emitRemainder
-			}
-			candidate = e.table[nextHash&tableMask]
-			now := load3232(src, nextS)
-			e.table[nextHash&tableMask] = tableEntry{offset: s + e.cur, val: cv}
-			nextHash = hash(now)
-
-			offset := s - (candidate.offset - e.cur)
-			if offset > maxMatchOffset || cv != candidate.val {
-				// Out of range or not matched.
-				cv = now
-				continue
-			}
-			break
-		}
-
-		// A 4-byte match has been found. We'll later see if more than 4 bytes
-		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
-		// them as literal bytes.
-		emitLiteral(dst, src[nextEmit:s])
-
-		// Call emitCopy, and then see if another emitCopy could be our next
-		// move. Repeat until we find no match for the input immediately after
-		// what was consumed by the last emitCopy call.
-		//
-		// If we exit this loop normally then we need to call emitLiteral next,
-		// though we don't yet know how big the literal will be. We handle that
-		// by proceeding to the next iteration of the main loop. We also can
-		// exit this loop via goto if we get close to exhausting the input.
-		for {
-			// Invariant: we have a 4-byte match at s, and no need to emit any
-			// literal bytes prior to s.
-
-			// Extend the 4-byte match as long as possible.
-			//
-			s += 4
-			t := candidate.offset - e.cur + 4
-			l := e.matchlen(s, t, src)
-
-			// matchToken is flate's equivalent of Snappy's emitCopy. (length,offset)
-			dst.tokens[dst.n] = matchToken(uint32(l+4-baseMatchLength), uint32(s-t-baseMatchOffset))
-			dst.n++
-			s += l
-			nextEmit = s
-			if s >= sLimit {
-				t += l
-				// Index first pair after match end.
-				if int(t+4) < len(src) && t > 0 {
-					cv := load3232(src, t)
-					e.table[hash(cv)&tableMask] = tableEntry{offset: t + e.cur, val: cv}
-				}
-				goto emitRemainder
-			}
-
-			// We could immediately start working at s now, but to improve
-			// compression we first update the hash table at s-1 and at s. If
-			// another emitCopy is not our next move, also calculate nextHash
-			// at s+1. At least on GOARCH=amd64, these three hash calculations
-			// are faster as one load64 call (with some shifts) instead of
-			// three load32 calls.
-			x := load6432(src, s-1)
-			prevHash := hash(uint32(x))
-			e.table[prevHash&tableMask] = tableEntry{offset: e.cur + s - 1, val: uint32(x)}
-			x >>= 8
-			currHash := hash(uint32(x))
-			candidate = e.table[currHash&tableMask]
-			e.table[currHash&tableMask] = tableEntry{offset: e.cur + s, val: uint32(x)}
-
-			offset := s - (candidate.offset - e.cur)
-			if offset > maxMatchOffset || uint32(x) != candidate.val {
-				cv = uint32(x >> 8)
-				nextHash = hash(cv)
-				s++
-				break
-			}
-		}
-	}
-
-emitRemainder:
-	if int(nextEmit) < len(src) {
-		emitLiteral(dst, src[nextEmit:])
-	}
-	e.cur += int32(len(src))
-	e.prev = e.prev[:len(src)]
-	copy(e.prev, src)
-}
-
-type tableEntryPrev struct {
-	Cur  tableEntry
-	Prev tableEntry
-}
-
-// snappyL3
-type snappyL3 struct {
-	snappyGen
-	table [tableSize]tableEntryPrev
-}
-
-// Encode uses a similar algorithm to level 2, will check up to two candidates.
-func (e *snappyL3) Encode(dst *tokens, src []byte) {
-	const (
-		inputMargin            = 8 - 1
-		minNonLiteralBlockSize = 1 + 1 + inputMargin
-	)
-
-	// Protect against e.cur wraparound.
-	if e.cur > 1<<30 {
-		for i := range e.table[:] {
-			e.table[i] = tableEntryPrev{}
-		}
-		e.snappyGen = snappyGen{cur: maxStoreBlockSize, prev: e.prev[:0]}
-	}
-
-	// This check isn't in the Snappy implementation, but there, the caller
-	// instead of the callee handles this case.
-	if len(src) < minNonLiteralBlockSize {
-		// We do not fill the token table.
-		// This will be picked up by caller.
-		dst.n = uint16(len(src))
-		e.cur += maxStoreBlockSize
-		e.prev = e.prev[:0]
-		return
-	}
-
-	// sLimit is when to stop looking for offset/length copies. The inputMargin
-	// lets us use a fast path for emitLiteral in the main loop, while we are
-	// looking for copies.
-	sLimit := int32(len(src) - inputMargin)
-
-	// nextEmit is where in src the next emitLiteral should start from.
-	nextEmit := int32(0)
-	s := int32(0)
-	cv := load3232(src, s)
-	nextHash := hash(cv)
-
-	for {
-		// Copied from the C++ snappy implementation:
-		//
-		// Heuristic match skipping: If 32 bytes are scanned with no matches
-		// found, start looking only at every other byte. If 32 more bytes are
-		// scanned (or skipped), look at every third byte, etc.. When a match
-		// is found, immediately go back to looking at every byte. This is a
-		// small loss (~5% performance, ~0.1% density) for compressible data
-		// due to more bookkeeping, but for non-compressible data (such as
-		// JPEG) it's a huge win since the compressor quickly "realizes" the
-		// data is incompressible and doesn't bother looking for matches
-		// everywhere.
-		//
-		// The "skip" variable keeps track of how many bytes there are since
-		// the last match; dividing it by 32 (ie. right-shifting by five) gives
-		// the number of bytes to move ahead for each iteration.
-		skip := int32(32)
-
-		nextS := s
-		var candidate tableEntry
-		for {
-			s = nextS
-			bytesBetweenHashLookups := skip >> 5
-			nextS = s + bytesBetweenHashLookups
-			skip += bytesBetweenHashLookups
-			if nextS > sLimit {
-				goto emitRemainder
-			}
-			candidates := e.table[nextHash&tableMask]
-			now := load3232(src, nextS)
-			e.table[nextHash&tableMask] = tableEntryPrev{Prev: candidates.Cur, Cur: tableEntry{offset: s + e.cur, val: cv}}
-			nextHash = hash(now)
-
-			// Check both candidates
-			candidate = candidates.Cur
-			if cv == candidate.val {
-				offset := s - (candidate.offset - e.cur)
-				if offset <= maxMatchOffset {
-					break
-				}
-			} else {
-				// We only check if value mismatches.
-				// Offset will always be invalid in other cases.
-				candidate = candidates.Prev
-				if cv == candidate.val {
-					offset := s - (candidate.offset - e.cur)
-					if offset <= maxMatchOffset {
-						break
-					}
-				}
-			}
-			cv = now
-		}
-
-		// A 4-byte match has been found. We'll later see if more than 4 bytes
-		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
-		// them as literal bytes.
-		emitLiteral(dst, src[nextEmit:s])
-
-		// Call emitCopy, and then see if another emitCopy could be our next
-		// move. Repeat until we find no match for the input immediately after
-		// what was consumed by the last emitCopy call.
-		//
-		// If we exit this loop normally then we need to call emitLiteral next,
-		// though we don't yet know how big the literal will be. We handle that
-		// by proceeding to the next iteration of the main loop. We also can
-		// exit this loop via goto if we get close to exhausting the input.
-		for {
-			// Invariant: we have a 4-byte match at s, and no need to emit any
-			// literal bytes prior to s.
-
-			// Extend the 4-byte match as long as possible.
-			//
-			s += 4
-			t := candidate.offset - e.cur + 4
-			l := e.matchlen(s, t, src)
-
-			// matchToken is flate's equivalent of Snappy's emitCopy. (length,offset)
-			dst.tokens[dst.n] = matchToken(uint32(l+4-baseMatchLength), uint32(s-t-baseMatchOffset))
-			dst.n++
-			s += l
-			nextEmit = s
-			if s >= sLimit {
-				t += l
-				// Index first pair after match end.
-				if int(t+4) < len(src) && t > 0 {
-					cv := load3232(src, t)
-					nextHash = hash(cv)
-					e.table[nextHash&tableMask] = tableEntryPrev{
-						Prev: e.table[nextHash&tableMask].Cur,
-						Cur:  tableEntry{offset: e.cur + t, val: cv},
-					}
-				}
-				goto emitRemainder
-			}
-
-			// We could immediately start working at s now, but to improve
-			// compression we first update the hash table at s-3 to s. If
-			// another emitCopy is not our next move, also calculate nextHash
-			// at s+1. At least on GOARCH=amd64, these three hash calculations
-			// are faster as one load64 call (with some shifts) instead of
-			// three load32 calls.
-			x := load6432(src, s-3)
-			prevHash := hash(uint32(x))
-			e.table[prevHash&tableMask] = tableEntryPrev{
-				Prev: e.table[prevHash&tableMask].Cur,
-				Cur:  tableEntry{offset: e.cur + s - 3, val: uint32(x)},
-			}
-			x >>= 8
-			prevHash = hash(uint32(x))
-
-			e.table[prevHash&tableMask] = tableEntryPrev{
-				Prev: e.table[prevHash&tableMask].Cur,
-				Cur:  tableEntry{offset: e.cur + s - 2, val: uint32(x)},
-			}
-			x >>= 8
-			prevHash = hash(uint32(x))
-
-			e.table[prevHash&tableMask] = tableEntryPrev{
-				Prev: e.table[prevHash&tableMask].Cur,
-				Cur:  tableEntry{offset: e.cur + s - 1, val: uint32(x)},
-			}
-			x >>= 8
-			currHash := hash(uint32(x))
-			candidates := e.table[currHash&tableMask]
-			cv = uint32(x)
-			e.table[currHash&tableMask] = tableEntryPrev{
-				Prev: candidates.Cur,
-				Cur:  tableEntry{offset: s + e.cur, val: cv},
-			}
-
-			// Check both candidates
-			candidate = candidates.Cur
-			if cv == candidate.val {
-				offset := s - (candidate.offset - e.cur)
-				if offset <= maxMatchOffset {
-					continue
-				}
-			} else {
-				// We only check if value mismatches.
-				// Offset will always be invalid in other cases.
-				candidate = candidates.Prev
-				if cv == candidate.val {
-					offset := s - (candidate.offset - e.cur)
-					if offset <= maxMatchOffset {
-						continue
-					}
-				}
-			}
-			cv = uint32(x >> 8)
-			nextHash = hash(cv)
-			s++
-			break
-		}
-	}
-
-emitRemainder:
-	if int(nextEmit) < len(src) {
-		emitLiteral(dst, src[nextEmit:])
-	}
-	e.cur += int32(len(src))
-	e.prev = e.prev[:len(src)]
-	copy(e.prev, src)
-}
-
-// snappyL4
-type snappyL4 struct {
-	snappyL3
-}
-
-// Encode uses a similar algorithm to level 3,
-// but will check up to two candidates if first isn't long enough.
-func (e *snappyL4) Encode(dst *tokens, src []byte) {
-	const (
-		inputMargin            = 8 - 3
-		minNonLiteralBlockSize = 1 + 1 + inputMargin
-		matchLenGood           = 12
-	)
-
-	// Protect against e.cur wraparound.
-	if e.cur > 1<<30 {
-		for i := range e.table[:] {
-			e.table[i] = tableEntryPrev{}
-		}
-		e.snappyGen = snappyGen{cur: maxStoreBlockSize, prev: e.prev[:0]}
-	}
-
-	// This check isn't in the Snappy implementation, but there, the caller
-	// instead of the callee handles this case.
-	if len(src) < minNonLiteralBlockSize {
-		// We do not fill the token table.
-		// This will be picked up by caller.
-		dst.n = uint16(len(src))
-		e.cur += maxStoreBlockSize
-		e.prev = e.prev[:0]
-		return
-	}
-
-	// sLimit is when to stop looking for offset/length copies. The inputMargin
-	// lets us use a fast path for emitLiteral in the main loop, while we are
-	// looking for copies.
-	sLimit := int32(len(src) - inputMargin)
-
-	// nextEmit is where in src the next emitLiteral should start from.
-	nextEmit := int32(0)
-	s := int32(0)
-	cv := load3232(src, s)
-	nextHash := hash(cv)
-
-	for {
-		// Copied from the C++ snappy implementation:
-		//
-		// Heuristic match skipping: If 32 bytes are scanned with no matches
-		// found, start looking only at every other byte. If 32 more bytes are
-		// scanned (or skipped), look at every third byte, etc.. When a match
-		// is found, immediately go back to looking at every byte. This is a
-		// small loss (~5% performance, ~0.1% density) for compressible data
-		// due to more bookkeeping, but for non-compressible data (such as
-		// JPEG) it's a huge win since the compressor quickly "realizes" the
-		// data is incompressible and doesn't bother looking for matches
-		// everywhere.
-		//
-		// The "skip" variable keeps track of how many bytes there are since
-		// the last match; dividing it by 32 (ie. right-shifting by five) gives
-		// the number of bytes to move ahead for each iteration.
-		skip := int32(32)
-
-		nextS := s
-		var candidate tableEntry
-		var candidateAlt tableEntry
-		for {
-			s = nextS
-			bytesBetweenHashLookups := skip >> 5
-			nextS = s + bytesBetweenHashLookups
-			skip += bytesBetweenHashLookups
-			if nextS > sLimit {
-				goto emitRemainder
-			}
-			candidates := e.table[nextHash&tableMask]
-			now := load3232(src, nextS)
-			e.table[nextHash&tableMask] = tableEntryPrev{Prev: candidates.Cur, Cur: tableEntry{offset: s + e.cur, val: cv}}
-			nextHash = hash(now)
-
-			// Check both candidates
-			candidate = candidates.Cur
-			if cv == candidate.val {
-				offset := s - (candidate.offset - e.cur)
-				if offset < maxMatchOffset {
-					offset = s - (candidates.Prev.offset - e.cur)
-					if cv == candidates.Prev.val && offset < maxMatchOffset {
-						candidateAlt = candidates.Prev
-					}
-					break
-				}
-			} else {
-				// We only check if value mismatches.
-				// Offset will always be invalid in other cases.
-				candidate = candidates.Prev
-				if cv == candidate.val {
-					offset := s - (candidate.offset - e.cur)
-					if offset < maxMatchOffset {
-						break
-					}
-				}
-			}
-			cv = now
-		}
-
-		// A 4-byte match has been found. We'll later see if more than 4 bytes
-		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
-		// them as literal bytes.
-		emitLiteral(dst, src[nextEmit:s])
-
-		// Call emitCopy, and then see if another emitCopy could be our next
-		// move. Repeat until we find no match for the input immediately after
-		// what was consumed by the last emitCopy call.
-		//
-		// If we exit this loop normally then we need to call emitLiteral next,
-		// though we don't yet know how big the literal will be. We handle that
-		// by proceeding to the next iteration of the main loop. We also can
-		// exit this loop via goto if we get close to exhausting the input.
-		for {
-			// Invariant: we have a 4-byte match at s, and no need to emit any
-			// literal bytes prior to s.
-
-			// Extend the 4-byte match as long as possible.
-			//
-			s += 4
-			t := candidate.offset - e.cur + 4
-			l := e.matchlen(s, t, src)
-			// Try alternative candidate if match length < matchLenGood.
-			if l < matchLenGood-4 && candidateAlt.offset != 0 {
-				t2 := candidateAlt.offset - e.cur + 4
-				l2 := e.matchlen(s, t2, src)
-				if l2 > l {
-					l = l2
-					t = t2
-				}
-			}
-			// matchToken is flate's equivalent of Snappy's emitCopy. (length,offset)
-			dst.tokens[dst.n] = matchToken(uint32(l+4-baseMatchLength), uint32(s-t-baseMatchOffset))
-			dst.n++
-			s += l
-			nextEmit = s
-			if s >= sLimit {
-				t += l
-				// Index first pair after match end.
-				if int(t+4) < len(src) && t > 0 {
-					cv := load3232(src, t)
-					nextHash = hash(cv)
-					e.table[nextHash&tableMask] = tableEntryPrev{
-						Prev: e.table[nextHash&tableMask].Cur,
-						Cur:  tableEntry{offset: e.cur + t, val: cv},
-					}
-				}
-				goto emitRemainder
-			}
-
-			// We could immediately start working at s now, but to improve
-			// compression we first update the hash table at s-3 to s. If
-			// another emitCopy is not our next move, also calculate nextHash
-			// at s+1. At least on GOARCH=amd64, these three hash calculations
-			// are faster as one load64 call (with some shifts) instead of
-			// three load32 calls.
-			x := load6432(src, s-3)
-			prevHash := hash(uint32(x))
-			e.table[prevHash&tableMask] = tableEntryPrev{
-				Prev: e.table[prevHash&tableMask].Cur,
-				Cur:  tableEntry{offset: e.cur + s - 3, val: uint32(x)},
-			}
-			x >>= 8
-			prevHash = hash(uint32(x))
-
-			e.table[prevHash&tableMask] = tableEntryPrev{
-				Prev: e.table[prevHash&tableMask].Cur,
-				Cur:  tableEntry{offset: e.cur + s - 2, val: uint32(x)},
-			}
-			x >>= 8
-			prevHash = hash(uint32(x))
-
-			e.table[prevHash&tableMask] = tableEntryPrev{
-				Prev: e.table[prevHash&tableMask].Cur,
-				Cur:  tableEntry{offset: e.cur + s - 1, val: uint32(x)},
-			}
-			x >>= 8
-			currHash := hash(uint32(x))
-			candidates := e.table[currHash&tableMask]
-			cv = uint32(x)
-			e.table[currHash&tableMask] = tableEntryPrev{
-				Prev: candidates.Cur,
-				Cur:  tableEntry{offset: s + e.cur, val: cv},
-			}
-
-			// Check both candidates
-			candidate = candidates.Cur
-			candidateAlt = tableEntry{}
-			if cv == candidate.val {
-				offset := s - (candidate.offset - e.cur)
-				if offset <= maxMatchOffset {
-					offset = s - (candidates.Prev.offset - e.cur)
-					if cv == candidates.Prev.val && offset <= maxMatchOffset {
-						candidateAlt = candidates.Prev
-					}
-					continue
-				}
-			} else {
-				// We only check if value mismatches.
-				// Offset will always be invalid in other cases.
-				candidate = candidates.Prev
-				if cv == candidate.val {
-					offset := s - (candidate.offset - e.cur)
-					if offset <= maxMatchOffset {
-						continue
-					}
-				}
-			}
-			cv = uint32(x >> 8)
-			nextHash = hash(cv)
-			s++
-			break
-		}
-	}
-
-emitRemainder:
-	if int(nextEmit) < len(src) {
-		emitLiteral(dst, src[nextEmit:])
-	}
-	e.cur += int32(len(src))
-	e.prev = e.prev[:len(src)]
-	copy(e.prev, src)
-}
-
-func (e *snappyGen) matchlen(s, t int32, src []byte) int32 {
-	s1 := int(s) + maxMatchLength - 4
-	if s1 > len(src) {
-		s1 = len(src)
-	}
-
-	// If we are inside the current block
-	if t >= 0 {
-		b := src[t:]
-		a := src[s:s1]
-		b = b[:len(a)]
-		// Extend the match to be as long as possible.
-		for i := range a {
-			if a[i] != b[i] {
-				return int32(i)
-			}
-		}
-		return int32(len(a))
-	}
-
-	// We found a match in the previous block.
-	tp := int32(len(e.prev)) + t
-	if tp < 0 {
-		return 0
-	}
-
-	// Extend the match to be as long as possible.
-	a := src[s:s1]
-	b := e.prev[tp:]
-	if len(b) > len(a) {
-		b = b[:len(a)]
-	}
-	a = a[:len(b)]
-	for i := range b {
-		if a[i] != b[i] {
-			return int32(i)
-		}
-	}
-
-	// If we reached our limit, we matched everything we are
-	// allowed to in the previous block and we return.
-	n := int32(len(b))
-	if int(s+n) == s1 {
-		return n
-	}
-
-	// Continue looking for more matches in the current block.
-	a = src[s+n : s1]
-	b = src[:len(a)]
-	for i := range a {
-		if a[i] != b[i] {
-			return int32(i) + n
-		}
-	}
-	return int32(len(a)) + n
-}
-
-// Reset the encoding table.
-func (e *snappyGen) Reset() {
-	e.prev = e.prev[:0]
-	e.cur += maxMatchOffset
-}
diff --git a/vendor/github.com/klauspost/compress/flate/stateless.go b/vendor/github.com/klauspost/compress/flate/stateless.go
new file mode 100644
index 000000000..524ee0ae3
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/flate/stateless.go
@@ -0,0 +1,252 @@
+package flate
+
+import (
+	"io"
+	"math"
+)
+
+const (
+	maxStatelessBlock = math.MaxInt16
+
+	slTableBits  = 13
+	slTableSize  = 1 << slTableBits
+	slTableShift = 32 - slTableBits
+)
+
+type statelessWriter struct {
+	dst    io.Writer
+	closed bool
+}
+
+func (s *statelessWriter) Close() error {
+	if s.closed {
+		return nil
+	}
+	s.closed = true
+	// Emit EOF block
+	return StatelessDeflate(s.dst, nil, true)
+}
+
+func (s *statelessWriter) Write(p []byte) (n int, err error) {
+	err = StatelessDeflate(s.dst, p, false)
+	if err != nil {
+		return 0, err
+	}
+	return len(p), nil
+}
+
+func (s *statelessWriter) Reset(w io.Writer) {
+	s.dst = w
+	s.closed = false
+}
+
+// NewStatelessWriter will do compression but without maintaining any state
+// between Write calls.
+// There will be no memory kept between Write calls,
+// but compression and speed will be suboptimal.
+// Because of this, the size of actual Write calls will affect output size.
+func NewStatelessWriter(dst io.Writer) io.WriteCloser {
+	return &statelessWriter{dst: dst}
+}
+
+// StatelessDeflate allows to compress directly to a Writer without retaining state.
+// When returning everything will be flushed.
+func StatelessDeflate(out io.Writer, in []byte, eof bool) error {
+	var dst tokens
+	bw := newHuffmanBitWriter(out)
+	if eof && len(in) == 0 {
+		// Just write an EOF block.
+		// Could be faster...
+		bw.writeStoredHeader(0, true)
+		bw.flush()
+		return bw.err
+	}
+
+	for len(in) > 0 {
+		todo := in
+		if len(todo) > maxStatelessBlock {
+			todo = todo[:maxStatelessBlock]
+		}
+		in = in[len(todo):]
+		// Compress
+		statelessEnc(&dst, todo)
+		isEof := eof && len(in) == 0
+
+		if dst.n == 0 {
+			bw.writeStoredHeader(len(todo), isEof)
+			if bw.err != nil {
+				return bw.err
+			}
+			bw.writeBytes(todo)
+		} else if int(dst.n) > len(todo)-len(todo)>>4 {
+			// If we removed less than 1/16th, huffman compress the block.
+			bw.writeBlockHuff(isEof, todo, false)
+		} else {
+			bw.writeBlockDynamic(&dst, isEof, todo, false)
+		}
+		if bw.err != nil {
+			return bw.err
+		}
+		dst.Reset()
+	}
+	if !eof {
+		// Align.
+		bw.writeStoredHeader(0, false)
+	}
+	bw.flush()
+	return bw.err
+}
+
+func hashSL(u uint32) uint32 {
+	return (u * 0x1e35a7bd) >> slTableShift
+}
+
+func load3216(b []byte, i int16) uint32 {
+	// Help the compiler eliminate bounds checks on the read so it can be done in a single read.
+	b = b[i:]
+	b = b[:4]
+	return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
+}
+
+func load6416(b []byte, i int16) uint64 {
+	// Help the compiler eliminate bounds checks on the read so it can be done in a single read.
+	b = b[i:]
+	b = b[:8]
+	return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
+		uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
+}
+
+func statelessEnc(dst *tokens, src []byte) {
+	const (
+		inputMargin            = 12 - 1
+		minNonLiteralBlockSize = 1 + 1 + inputMargin
+	)
+
+	type tableEntry struct {
+		offset int16
+	}
+
+	var table [slTableSize]tableEntry
+
+	// This check isn't in the Snappy implementation, but there, the caller
+	// instead of the callee handles this case.
+	if len(src) < minNonLiteralBlockSize {
+		// We do not fill the token table.
+		// This will be picked up by caller.
+		dst.n = uint16(len(src))
+		return
+	}
+
+	s := int16(1)
+	nextEmit := int16(0)
+	// sLimit is when to stop looking for offset/length copies. The inputMargin
+	// lets us use a fast path for emitLiteral in the main loop, while we are
+	// looking for copies.
+	sLimit := int16(len(src) - inputMargin)
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	cv := load3216(src, s)
+
+	for {
+		const skipLog = 5
+		const doEvery = 2
+
+		nextS := s
+		var candidate tableEntry
+		for {
+			nextHash := hashSL(cv)
+			candidate = table[nextHash]
+			nextS = s + doEvery + (s-nextEmit)>>skipLog
+			if nextS > sLimit || nextS <= 0 {
+				goto emitRemainder
+			}
+
+			now := load6416(src, nextS)
+			table[nextHash] = tableEntry{offset: s}
+			nextHash = hashSL(uint32(now))
+
+			if cv == load3216(src, candidate.offset) {
+				table[nextHash] = tableEntry{offset: nextS}
+				break
+			}
+
+			// Do one right away...
+			cv = uint32(now)
+			s = nextS
+			nextS++
+			candidate = table[nextHash]
+			now >>= 8
+			table[nextHash] = tableEntry{offset: s}
+
+			if cv == load3216(src, candidate.offset) {
+				table[nextHash] = tableEntry{offset: nextS}
+				break
+			}
+			cv = uint32(now)
+			s = nextS
+		}
+
+		// A 4-byte match has been found. We'll later see if more than 4 bytes
+		// match. But, prior to the match, src[nextEmit:s] are unmatched. Emit
+		// them as literal bytes.
+		for {
+			// Invariant: we have a 4-byte match at s, and no need to emit any
+			// literal bytes prior to s.
+
+			// Extend the 4-byte match as long as possible.
+			t := candidate.offset
+			l := int16(matchLen(src[s+4:], src[t+4:]) + 4)
+
+			// Extend backwards
+			for t > 0 && s > nextEmit && src[t-1] == src[s-1] {
+				s--
+				t--
+				l++
+			}
+			if nextEmit < s {
+				emitLiteral(dst, src[nextEmit:s])
+			}
+
+			// Save the match found
+			dst.AddMatchLong(int32(l), uint32(s-t-baseMatchOffset))
+			s += l
+			nextEmit = s
+			if nextS >= s {
+				s = nextS + 1
+			}
+			if s >= sLimit {
+				goto emitRemainder
+			}
+
+			// We could immediately start working at s now, but to improve
+			// compression we first update the hash table at s-2 and at s. If
+			// another emitCopy is not our next move, also calculate nextHash
+			// at s+1. At least on GOARCH=amd64, these three hash calculations
+			// are faster as one load64 call (with some shifts) instead of
+			// three load32 calls.
+			x := load6416(src, s-2)
+			o := s - 2
+			prevHash := hashSL(uint32(x))
+			table[prevHash] = tableEntry{offset: o}
+			x >>= 16
+			currHash := hashSL(uint32(x))
+			candidate = table[currHash]
+			table[currHash] = tableEntry{offset: o + 2}
+
+			if uint32(x) != load3216(src, candidate.offset) {
+				cv = uint32(x >> 8)
+				s++
+				break
+			}
+		}
+	}
+
+emitRemainder:
+	if int(nextEmit) < len(src) {
+		// If nothing was added, don't encode literals.
+		if dst.n == 0 {
+			return
+		}
+		emitLiteral(dst, src[nextEmit:])
+	}
+}
diff --git a/vendor/github.com/klauspost/compress/flate/token.go b/vendor/github.com/klauspost/compress/flate/token.go
index 141299b97..b3df0d894 100644
--- a/vendor/github.com/klauspost/compress/flate/token.go
+++ b/vendor/github.com/klauspost/compress/flate/token.go
@@ -4,6 +4,14 @@
 
 package flate
 
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"io"
+	"math"
+)
+
 const (
 	// 2 bits:   type   0 = literal  1=EOF  2=Match   3=Unused
 	// 8 bits:   xlength = length - MIN_MATCH_LENGTH
@@ -46,6 +54,36 @@ var lengthCodes = [256]uint8{
 	27, 27, 27, 27, 27, 28,
 }
 
+// lengthCodes1 is length codes, but starting at 1.
+var lengthCodes1 = [256]uint8{
+	1, 2, 3, 4, 5, 6, 7, 8, 9, 9,
+	10, 10, 11, 11, 12, 12, 13, 13, 13, 13,
+	14, 14, 14, 14, 15, 15, 15, 15, 16, 16,
+	16, 16, 17, 17, 17, 17, 17, 17, 17, 17,
+	18, 18, 18, 18, 18, 18, 18, 18, 19, 19,
+	19, 19, 19, 19, 19, 19, 20, 20, 20, 20,
+	20, 20, 20, 20, 21, 21, 21, 21, 21, 21,
+	21, 21, 21, 21, 21, 21, 21, 21, 21, 21,
+	22, 22, 22, 22, 22, 22, 22, 22, 22, 22,
+	22, 22, 22, 22, 22, 22, 23, 23, 23, 23,
+	23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
+	23, 23, 24, 24, 24, 24, 24, 24, 24, 24,
+	24, 24, 24, 24, 24, 24, 24, 24, 25, 25,
+	25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
+	25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
+	25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
+	26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
+	26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
+	26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
+	26, 26, 27, 27, 27, 27, 27, 27, 27, 27,
+	27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
+	27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
+	27, 27, 27, 27, 28, 28, 28, 28, 28, 28,
+	28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+	28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+	28, 28, 28, 28, 28, 29,
+}
+
 var offsetCodes = [256]uint32{
 	0, 1, 2, 3, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 7, 7,
 	8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 9, 9, 9,
@@ -65,19 +103,236 @@ var offsetCodes = [256]uint32{
 	15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15,
 }
 
+// offsetCodes14 are offsetCodes, but with 14 added.
+var offsetCodes14 = [256]uint32{
+	14, 15, 16, 17, 18, 18, 19, 19, 20, 20, 20, 20, 21, 21, 21, 21,
+	22, 22, 22, 22, 22, 22, 22, 22, 23, 23, 23, 23, 23, 23, 23, 23,
+	24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
+	25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25,
+	26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
+	26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26, 26,
+	27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
+	27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27,
+	28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+	28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+	28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+	28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28, 28,
+	29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
+	29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
+	29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
+	29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29, 29,
+}
+
 type token uint32
 
 type tokens struct {
-	tokens [maxStoreBlockSize + 1]token
-	n      uint16 // Must be able to contain maxStoreBlockSize
+	nLits     int
+	extraHist [32]uint16  // codes 256->maxnumlit
+	offHist   [32]uint16  // offset codes
+	litHist   [256]uint16 // codes 0->255
+	n         uint16      // Must be able to contain maxStoreBlockSize
+	tokens    [maxStoreBlockSize + 1]token
+}
+
+func (t *tokens) Reset() {
+	if t.n == 0 {
+		return
+	}
+	t.n = 0
+	t.nLits = 0
+	for i := range t.litHist[:] {
+		t.litHist[i] = 0
+	}
+	for i := range t.extraHist[:] {
+		t.extraHist[i] = 0
+	}
+	for i := range t.offHist[:] {
+		t.offHist[i] = 0
+	}
+}
+
+func (t *tokens) Fill() {
+	if t.n == 0 {
+		return
+	}
+	for i, v := range t.litHist[:] {
+		if v == 0 {
+			t.litHist[i] = 1
+			t.nLits++
+		}
+	}
+	for i, v := range t.extraHist[:literalCount-256] {
+		if v == 0 {
+			t.nLits++
+			t.extraHist[i] = 1
+		}
+	}
+	for i, v := range t.offHist[:offsetCodeCount] {
+		if v == 0 {
+			t.offHist[i] = 1
+		}
+	}
+}
+
+func indexTokens(in []token) tokens {
+	var t tokens
+	t.indexTokens(in)
+	return t
+}
+
+func (t *tokens) indexTokens(in []token) {
+	t.Reset()
+	for _, tok := range in {
+		if tok < matchType {
+			t.tokens[t.n] = tok
+			t.litHist[tok]++
+			t.n++
+			continue
+		}
+		t.AddMatch(uint32(tok.length()), tok.offset())
+	}
 }
 
-// Convert a literal into a literal token.
-func literalToken(literal uint32) token { return token(literalType + literal) }
+// emitLiteral writes a literal chunk and returns the number of bytes written.
+func emitLiteral(dst *tokens, lit []byte) {
+	ol := int(dst.n)
+	for i, v := range lit {
+		dst.tokens[(i+ol)&maxStoreBlockSize] = token(v)
+		dst.litHist[v]++
+	}
+	dst.n += uint16(len(lit))
+	dst.nLits += len(lit)
+}
 
-// Convert a < xlength, xoffset > pair into a match token.
-func matchToken(xlength uint32, xoffset uint32) token {
-	return token(matchType + xlength<<lengthShift + xoffset)
+func (t *tokens) AddLiteral(lit byte) {
+	t.tokens[t.n] = token(lit)
+	t.litHist[lit]++
+	t.n++
+	t.nLits++
+}
+
+// EstimatedBits will return an minimum size estimated by an *optimal*
+// compression of the block.
+// The size of the block
+func (t *tokens) EstimatedBits() int {
+	shannon := float64(0)
+	bits := int(0)
+	nMatches := 0
+	if t.nLits > 0 {
+		invTotal := 1.0 / float64(t.nLits)
+		for _, v := range t.litHist[:] {
+			if v > 0 {
+				n := float64(v)
+				shannon += math.Ceil(-math.Log2(n*invTotal) * n)
+			}
+		}
+		// Just add 15 for EOB
+		shannon += 15
+		for _, v := range t.extraHist[1 : literalCount-256] {
+			if v > 0 {
+				n := float64(v)
+				shannon += math.Ceil(-math.Log2(n*invTotal) * n)
+				bits += int(lengthExtraBits[v&31]) * int(v)
+				nMatches += int(v)
+			}
+		}
+	}
+	if nMatches > 0 {
+		invTotal := 1.0 / float64(nMatches)
+		for _, v := range t.offHist[:offsetCodeCount] {
+			if v > 0 {
+				n := float64(v)
+				shannon += math.Ceil(-math.Log2(n*invTotal) * n)
+				bits += int(offsetExtraBits[v&31]) * int(n)
+			}
+		}
+	}
+
+	return int(shannon) + bits
+}
+
+// AddMatch adds a match to the tokens.
+// This function is very sensitive to inlining and right on the border.
+func (t *tokens) AddMatch(xlength uint32, xoffset uint32) {
+	if debugDecode {
+		if xlength >= maxMatchLength+baseMatchLength {
+			panic(fmt.Errorf("invalid length: %v", xlength))
+		}
+		if xoffset >= maxMatchOffset+baseMatchOffset {
+			panic(fmt.Errorf("invalid offset: %v", xoffset))
+		}
+	}
+	t.nLits++
+	lengthCode := lengthCodes1[uint8(xlength)] & 31
+	t.tokens[t.n] = token(matchType | xlength<<lengthShift | xoffset)
+	t.extraHist[lengthCode]++
+	t.offHist[offsetCode(xoffset)&31]++
+	t.n++
+}
+
+// AddMatchLong adds a match to the tokens, potentially longer than max match length.
+// Length should NOT have the base subtracted, only offset should.
+func (t *tokens) AddMatchLong(xlength int32, xoffset uint32) {
+	if debugDecode {
+		if xoffset >= maxMatchOffset+baseMatchOffset {
+			panic(fmt.Errorf("invalid offset: %v", xoffset))
+		}
+	}
+	oc := offsetCode(xoffset) & 31
+	for xlength > 0 {
+		xl := xlength
+		if xl > 258 {
+			// We need to have at least baseMatchLength left over for next loop.
+			xl = 258 - baseMatchLength
+		}
+		xlength -= xl
+		xl -= 3
+		t.nLits++
+		lengthCode := lengthCodes1[uint8(xl)] & 31
+		t.tokens[t.n] = token(matchType | uint32(xl)<<lengthShift | xoffset)
+		t.extraHist[lengthCode]++
+		t.offHist[oc]++
+		t.n++
+	}
+}
+
+func (t *tokens) AddEOB() {
+	t.tokens[t.n] = token(endBlockMarker)
+	t.extraHist[0]++
+	t.n++
+}
+
+func (t *tokens) Slice() []token {
+	return t.tokens[:t.n]
+}
+
+// VarInt returns the tokens as varint encoded bytes.
+func (t *tokens) VarInt() []byte {
+	var b = make([]byte, binary.MaxVarintLen32*int(t.n))
+	var off int
+	for _, v := range t.tokens[:t.n] {
+		off += binary.PutUvarint(b[off:], uint64(v))
+	}
+	return b[:off]
+}
+
+// FromVarInt restores t to the varint encoded tokens provided.
+// Any data in t is removed.
+func (t *tokens) FromVarInt(b []byte) error {
+	var buf = bytes.NewReader(b)
+	var toks []token
+	for {
+		r, err := binary.ReadUvarint(buf)
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+		toks = append(toks, token(r))
+	}
+	t.indexTokens(toks)
+	return nil
 }
 
 // Returns the type of a token
@@ -96,11 +351,17 @@ func lengthCode(len uint8) uint32 { return uint32(lengthCodes[len]) }
 
 // Returns the offset code corresponding to a specific offset
 func offsetCode(off uint32) uint32 {
+	if false {
+		if off < uint32(len(offsetCodes)) {
+			return offsetCodes[off&255]
+		} else if off>>7 < uint32(len(offsetCodes)) {
+			return offsetCodes[(off>>7)&255] + 14
+		} else {
+			return offsetCodes[(off>>14)&255] + 28
+		}
+	}
 	if off < uint32(len(offsetCodes)) {
-		return offsetCodes[off&255]
-	} else if off>>7 < uint32(len(offsetCodes)) {
-		return offsetCodes[(off>>7)&255] + 14
-	} else {
-		return offsetCodes[(off>>14)&255] + 28
+		return offsetCodes[uint8(off)]
 	}
+	return offsetCodes14[uint8(off>>7)]
 }
diff --git a/vendor/github.com/klauspost/compress/huff0/compress.go b/vendor/github.com/klauspost/compress/huff0/compress.go
index dd4f7fefb..51e00aaeb 100644
--- a/vendor/github.com/klauspost/compress/huff0/compress.go
+++ b/vendor/github.com/klauspost/compress/huff0/compress.go
@@ -54,6 +54,12 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
 		canReuse = s.canUseTable(s.prevTable)
 	}
 
+	// We want the output size to be less than this:
+	wantSize := len(in)
+	if s.WantLogLess > 0 {
+		wantSize -= wantSize >> s.WantLogLess
+	}
+
 	// Reset for next run.
 	s.clearCount = true
 	s.maxCount = 0
@@ -77,7 +83,7 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
 		s.cTable = s.prevTable
 		s.Out, err = compressor(in)
 		s.cTable = keepTable
-		if err == nil && len(s.Out) < len(in) {
+		if err == nil && len(s.Out) < wantSize {
 			s.OutData = s.Out
 			return s.Out, true, nil
 		}
@@ -100,13 +106,16 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
 		hSize := len(s.Out)
 		oldSize := s.prevTable.estimateSize(s.count[:s.symbolLen])
 		newSize := s.cTable.estimateSize(s.count[:s.symbolLen])
-		if oldSize <= hSize+newSize || hSize+12 >= len(in) {
+		if oldSize <= hSize+newSize || hSize+12 >= wantSize {
 			// Retain cTable even if we re-use.
 			keepTable := s.cTable
 			s.cTable = s.prevTable
 			s.Out, err = compressor(in)
 			s.cTable = keepTable
-			if len(s.Out) >= len(in) {
+			if err != nil {
+				return nil, false, err
+			}
+			if len(s.Out) >= wantSize {
 				return nil, false, ErrIncompressible
 			}
 			s.OutData = s.Out
@@ -128,7 +137,7 @@ func compress(in []byte, s *Scratch, compressor func(src []byte) ([]byte, error)
 		s.OutTable = nil
 		return nil, false, err
 	}
-	if len(s.Out) >= len(in) {
+	if len(s.Out) >= wantSize {
 		s.OutTable = nil
 		return nil, false, ErrIncompressible
 	}
diff --git a/vendor/github.com/klauspost/compress/huff0/decompress.go b/vendor/github.com/klauspost/compress/huff0/decompress.go
index 43b4815b3..7e68a4eb4 100644
--- a/vendor/github.com/klauspost/compress/huff0/decompress.go
+++ b/vendor/github.com/klauspost/compress/huff0/decompress.go
@@ -276,6 +276,7 @@ func (s *Scratch) Decompress4X(in []byte, dstSize int) (out []byte, err error) {
 	// Use temp table to avoid bound checks/append penalty.
 	var tmp = s.huffWeight[:256]
 	var off uint8
+	var decoded int
 
 	// Decode 2 values from each decoder/loop.
 	const bufoff = 256 / 4
@@ -306,6 +307,7 @@ bigloop:
 			copy(dstOut[dstEvery*3:], tmp[bufoff*3:bufoff*4])
 			off = 0
 			dstOut = dstOut[bufoff:]
+			decoded += 256
 			// There must at least be 3 buffers left.
 			if len(dstOut) < dstEvery*3 {
 				return nil, errors.New("corruption detected: stream overrun 2")
@@ -321,9 +323,11 @@ bigloop:
 		copy(dstOut[dstEvery:dstEvery+ioff], tmp[bufoff:bufoff*2])
 		copy(dstOut[dstEvery*2:dstEvery*2+ioff], tmp[bufoff*2:bufoff*3])
 		copy(dstOut[dstEvery*3:dstEvery*3+ioff], tmp[bufoff*3:bufoff*4])
+		decoded += int(off) * 4
 		dstOut = dstOut[off:]
 	}
 
+	// Decode remaining.
 	for i := range br {
 		offset := dstEvery * i
 		br := &br[i]
@@ -335,12 +339,15 @@ bigloop:
 			dstOut[offset] = decode(br)
 			offset++
 		}
+		decoded += offset - dstEvery*i
 		err = br.close()
 		if err != nil {
 			return nil, err
 		}
 	}
-
+	if dstSize != decoded {
+		return nil, errors.New("corruption detected: short output block")
+	}
 	return s.Out, nil
 }
 
diff --git a/vendor/github.com/klauspost/compress/huff0/huff0.go b/vendor/github.com/klauspost/compress/huff0/huff0.go
index 6f823f94d..6bc23bbf0 100644
--- a/vendor/github.com/klauspost/compress/huff0/huff0.go
+++ b/vendor/github.com/klauspost/compress/huff0/huff0.go
@@ -89,6 +89,12 @@ type Scratch struct {
 	// Reuse will specify the reuse policy
 	Reuse ReusePolicy
 
+	// WantLogLess allows to specify a log 2 reduction that should at least be achieved,
+	// otherwise the block will be returned as incompressible.
+	// The reduction should then at least be (input size >> WantLogLess)
+	// If WantLogLess == 0 any improvement will do.
+	WantLogLess uint8
+
 	// MaxDecodedSize will set the maximum allowed output size.
 	// This value will automatically be set to BlockSizeMax if not set.
 	// Decoders will return ErrMaxDecodedSizeExceeded is this limit is exceeded.
diff --git a/vendor/github.com/klauspost/compress/zstd/blockdec.go b/vendor/github.com/klauspost/compress/zstd/blockdec.go
index 3e161ea15..47cc21d6d 100644
--- a/vendor/github.com/klauspost/compress/zstd/blockdec.go
+++ b/vendor/github.com/klauspost/compress/zstd/blockdec.go
@@ -11,6 +11,7 @@ import (
 	"sync"
 
 	"github.com/klauspost/compress/huff0"
+	"github.com/klauspost/compress/zstd/internal/xxhash"
 )
 
 type blockType uint8
@@ -160,7 +161,8 @@ func (b *blockDec) reset(br byteBuffer, windowSize uint64) error {
 	b.data, err = br.readBig(cSize, b.dataStorage)
 	if err != nil {
 		if debug {
-			println("Reading block:", err)
+			println("Reading block:", err, "(", cSize, ")", len(b.data))
+			printf("%T", br)
 		}
 		return err
 	}
@@ -275,7 +277,7 @@ func (b *blockDec) decodeBuf(hist *history) error {
 		hist.b = nil
 		err := b.decodeCompressed(hist)
 		if debug {
-			println("Decompressed to total", len(b.dst), "bytes, error:", err)
+			println("Decompressed to total", len(b.dst), "bytes, hash:", xxhash.Sum64(b.dst), "error:", err)
 		}
 		hist.b = b.dst
 		b.dst = saved
@@ -368,7 +370,7 @@ func (b *blockDec) decodeCompressed(hist *history) error {
 		}
 	}
 	if debug {
-		println("literals type:", litType, "litRegenSize:", litRegenSize, "litCompSize", litCompSize)
+		println("literals type:", litType, "litRegenSize:", litRegenSize, "litCompSize:", litCompSize, "sizeFormat:", sizeFormat, "4X:", fourStreams)
 	}
 	var literals []byte
 	var huff *huff0.Scratch
@@ -426,7 +428,6 @@ func (b *blockDec) decodeCompressed(hist *history) error {
 		}
 		literals = in[:litCompSize]
 		in = in[litCompSize:]
-
 		huff = huffDecoderPool.Get().(*huff0.Scratch)
 		var err error
 		// Ensure we have space to store it.
@@ -637,7 +638,7 @@ func (b *blockDec) decodeCompressed(hist *history) error {
 		hist.huffTree = huff
 	}
 	if debug {
-		println("Final literals:", len(literals), "and", nSeqs, "sequences.")
+		println("Final literals:", len(literals), "hash:", xxhash.Sum64(literals), "and", nSeqs, "sequences.")
 	}
 
 	if nSeqs == 0 {
diff --git a/vendor/github.com/klauspost/compress/zstd/blockenc.go b/vendor/github.com/klauspost/compress/zstd/blockenc.go
index 9d9151a0e..8383279d2 100644
--- a/vendor/github.com/klauspost/compress/zstd/blockenc.go
+++ b/vendor/github.com/klauspost/compress/zstd/blockenc.go
@@ -51,7 +51,7 @@ func (b *blockEnc) init() {
 		b.coders.llEnc = &fseEncoder{}
 		b.coders.llPrev = &fseEncoder{}
 	}
-	b.litEnc = &huff0.Scratch{}
+	b.litEnc = &huff0.Scratch{WantLogLess: 4}
 	b.reset(nil)
 }
 
@@ -391,6 +391,52 @@ func (b *blockEnc) encodeLits() error {
 	return nil
 }
 
+// fuzzFseEncoder can be used to fuzz the FSE encoder.
+func fuzzFseEncoder(data []byte) int {
+	if len(data) > maxSequences || len(data) < 2 {
+		return 0
+	}
+	enc := fseEncoder{}
+	hist := enc.Histogram()[:256]
+	maxSym := uint8(0)
+	for i, v := range data {
+		v = v & 63
+		data[i] = v
+		hist[v]++
+		if v > maxSym {
+			maxSym = v
+		}
+	}
+	if maxSym == 0 {
+		// All 0
+		return 0
+	}
+	maxCount := func(a []uint32) int {
+		var max uint32
+		for _, v := range a {
+			if v > max {
+				max = v
+			}
+		}
+		return int(max)
+	}
+	cnt := maxCount(hist[:maxSym])
+	if cnt == len(data) {
+		// RLE
+		return 0
+	}
+	enc.HistogramFinished(maxSym, cnt)
+	err := enc.normalizeCount(len(data))
+	if err != nil {
+		return 0
+	}
+	_, err = enc.writeCount(nil)
+	if err != nil {
+		panic(err)
+	}
+	return 1
+}
+
 // encode will encode the block and put the output in b.output.
 func (b *blockEnc) encode() error {
 	if len(b.sequences) == 0 {
@@ -415,16 +461,10 @@ func (b *blockEnc) encode() 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 {
-			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 {
-			err = huff0.ErrIncompressible
-		}
 	} else {
 		err = huff0.ErrIncompressible
 	}
@@ -711,7 +751,7 @@ func (b *blockEnc) encode() error {
 	return nil
 }
 
-var errIncompressible = errors.New("uncompressible")
+var errIncompressible = errors.New("incompressible")
 
 func (b *blockEnc) genCodes() {
 	if len(b.sequences) == 0 {
diff --git a/vendor/github.com/klauspost/compress/zstd/bytebuf.go b/vendor/github.com/klauspost/compress/zstd/bytebuf.go
index 3538063f1..07321acb1 100644
--- a/vendor/github.com/klauspost/compress/zstd/bytebuf.go
+++ b/vendor/github.com/klauspost/compress/zstd/bytebuf.go
@@ -101,6 +101,9 @@ func (r *readerWrapper) readBig(n int, dst []byte) ([]byte, error) {
 		dst = make([]byte, n)
 	}
 	n2, err := io.ReadFull(r.r, dst[:n])
+	if err == io.EOF && n > 0 {
+		err = io.ErrUnexpectedEOF
+	}
 	return dst[:n2], err
 }
 
diff --git a/vendor/github.com/klauspost/compress/zstd/decoder.go b/vendor/github.com/klauspost/compress/zstd/decoder.go
index f4db3096a..1de94eef0 100644
--- a/vendor/github.com/klauspost/compress/zstd/decoder.go
+++ b/vendor/github.com/klauspost/compress/zstd/decoder.go
@@ -75,6 +75,7 @@ var (
 // The Reset function can be used to initiate a new stream, which is will considerably
 // reduce the allocations normally caused by NewReader.
 func NewReader(r io.Reader, opts ...DOption) (*Decoder, error) {
+	initPredefined()
 	var d Decoder
 	d.o.setDefault()
 	for _, o := range opts {
@@ -123,7 +124,9 @@ func (d *Decoder) Read(p []byte) (int, error) {
 			if d.current.err != nil {
 				break
 			}
-			d.nextBlock()
+			if !d.nextBlock(n == 0) {
+				return n, nil
+			}
 		}
 	}
 	if len(d.current.b) > 0 {
@@ -251,7 +254,7 @@ func (d *Decoder) WriteTo(w io.Writer) (int64, error) {
 		if d.current.err != nil {
 			break
 		}
-		d.nextBlock()
+		d.nextBlock(true)
 	}
 	err := d.current.err
 	if err != nil {
@@ -328,7 +331,10 @@ func (d *Decoder) DecodeAll(input, dst []byte) ([]byte, error) {
 
 // nextBlock returns the next block.
 // If an error occurs d.err will be set.
-func (d *Decoder) nextBlock() {
+// Optionally the function can block for new output.
+// If non-blocking mode is used the returned boolean will be false
+// if no data was available without blocking.
+func (d *Decoder) nextBlock(blocking bool) (ok bool) {
 	if d.current.d != nil {
 		if debug {
 			printf("re-adding current decoder %p", d.current.d)
@@ -338,12 +344,22 @@ func (d *Decoder) nextBlock() {
 	}
 	if d.current.err != nil {
 		// Keep error state.
-		return
+		return blocking
+	}
+
+	if blocking {
+		d.current.decodeOutput = <-d.current.output
+	} else {
+		select {
+		case d.current.decodeOutput = <-d.current.output:
+		default:
+			return false
+		}
 	}
-	d.current.decodeOutput = <-d.current.output
 	if debug {
 		println("got", len(d.current.b), "bytes, error:", d.current.err)
 	}
+	return true
 }
 
 // Close will release all resources.
diff --git a/vendor/github.com/klauspost/compress/zstd/enc_dfast.go b/vendor/github.com/klauspost/compress/zstd/enc_dfast.go
index e120625d8..2f41bcd0d 100644
--- a/vendor/github.com/klauspost/compress/zstd/enc_dfast.go
+++ b/vendor/github.com/klauspost/compress/zstd/enc_dfast.go
@@ -235,7 +235,7 @@ encodeLoop:
 				if debug && s-t > e.maxMatchOff {
 					panic("s - t >e.maxMatchOff")
 				}
-				if debug {
+				if debugMatches {
 					println("long match")
 				}
 				break
@@ -259,7 +259,7 @@ encodeLoop:
 					// but the likelihood of both the first 4 bytes and the hash matching should be enough.
 					t = candidateL.offset - e.cur
 					s += checkAt
-					if debug {
+					if debugMatches {
 						println("long match (after short)")
 					}
 					break
@@ -275,7 +275,7 @@ encodeLoop:
 				if debug && t < 0 {
 					panic("t<0")
 				}
-				if debug {
+				if debugMatches {
 					println("short match")
 				}
 				break
diff --git a/vendor/github.com/klauspost/compress/zstd/encoder.go b/vendor/github.com/klauspost/compress/zstd/encoder.go
index b7011be29..d79188271 100644
--- a/vendor/github.com/klauspost/compress/zstd/encoder.go
+++ b/vendor/github.com/klauspost/compress/zstd/encoder.go
@@ -59,6 +59,7 @@ type encoderState struct {
 // NewWriter will create a new Zstandard encoder.
 // If the encoder will be used for encoding blocks a nil writer can be used.
 func NewWriter(w io.Writer, opts ...EOption) (*Encoder, error) {
+	initPredefined()
 	var e Encoder
 	e.o.setDefault()
 	for _, o := range opts {
@@ -393,12 +394,31 @@ func (e *Encoder) Close() error {
 
 // EncodeAll will encode all input in src and append it to dst.
 // This function can be called concurrently, but each call will only run on a single goroutine.
-// If empty input is given, nothing is returned.
+// If empty input is given, nothing is returned, unless WithZeroFrames is specified.
 // Encoded blocks can be concatenated and the result will be the combined input stream.
 // Data compressed with EncodeAll can be decoded with the Decoder,
 // using either a stream or DecodeAll.
 func (e *Encoder) EncodeAll(src, dst []byte) []byte {
 	if len(src) == 0 {
+		if e.o.fullZero {
+			// Add frame header.
+			fh := frameHeader{
+				ContentSize:   0,
+				WindowSize:    MinWindowSize,
+				SingleSegment: true,
+				// Adding a checksum would be a waste of space.
+				Checksum: false,
+				DictID:   0,
+			}
+			dst, _ = fh.appendTo(dst)
+
+			// Write raw block as last one only.
+			var blk blockHeader
+			blk.setSize(0)
+			blk.setType(blockTypeRaw)
+			blk.setLast(true)
+			dst = blk.appendTo(dst)
+		}
 		return dst
 	}
 	e.init.Do(func() {
diff --git a/vendor/github.com/klauspost/compress/zstd/encoder_options.go b/vendor/github.com/klauspost/compress/zstd/encoder_options.go
index a8559e900..0f83a325a 100644
--- a/vendor/github.com/klauspost/compress/zstd/encoder_options.go
+++ b/vendor/github.com/klauspost/compress/zstd/encoder_options.go
@@ -1,6 +1,7 @@
 package zstd
 
 import (
+	"errors"
 	"fmt"
 	"runtime"
 	"strings"
@@ -18,6 +19,7 @@ type encoderOptions struct {
 	blockSize  int
 	windowSize int
 	level      EncoderLevel
+	fullZero   bool
 }
 
 func (o *encoderOptions) setDefault() {
@@ -63,6 +65,30 @@ func WithEncoderConcurrency(n int) EOption {
 	}
 }
 
+// WithWindowSize will set the maximum allowed back-reference distance.
+// The value must be a power of two between WindowSizeMin and WindowSizeMax.
+// A larger value will enable better compression but allocate more memory and,
+// for above-default values, take considerably longer.
+// The default value is determined by the compression level.
+func WithWindowSize(n int) EOption {
+	return func(o *encoderOptions) error {
+		switch {
+		case n < MinWindowSize:
+			return fmt.Errorf("window size must be at least %d", MinWindowSize)
+		case n > MaxWindowSize:
+			return fmt.Errorf("window size must be at most %d", MaxWindowSize)
+		case (n & (n - 1)) != 0:
+			return errors.New("window size must be a power of 2")
+		}
+
+		o.windowSize = n
+		if o.blockSize > o.windowSize {
+			o.blockSize = o.windowSize
+		}
+		return nil
+	}
+}
+
 // WithEncoderPadding will add padding to all output so the size will be a multiple of n.
 // This can be used to obfuscate the exact output size or make blocks of a certain size.
 // The contents will be a skippable frame, so it will be invisible by the decoder.
@@ -166,6 +192,16 @@ func WithEncoderLevel(l EncoderLevel) EOption {
 	}
 }
 
+// WithZeroFrames will encode 0 length input as full frames.
+// This can be needed for compatibility with zstandard usage,
+// but is not needed for this package.
+func WithZeroFrames(b bool) EOption {
+	return func(o *encoderOptions) error {
+		o.fullZero = b
+		return nil
+	}
+}
+
 // WithSingleSegment will set the "single segment" flag when EncodeAll is used.
 // If this flag is set, data must be regenerated within a single continuous memory segment.
 // In this case, Window_Descriptor byte is skipped, but Frame_Content_Size is necessarily present.
diff --git a/vendor/github.com/klauspost/compress/zstd/framedec.go b/vendor/github.com/klauspost/compress/zstd/framedec.go
index 839a95fbf..9e00437a2 100644
--- a/vendor/github.com/klauspost/compress/zstd/framedec.go
+++ b/vendor/github.com/klauspost/compress/zstd/framedec.go
@@ -49,7 +49,8 @@ type frameDec struct {
 
 const (
 	// The minimum Window_Size is 1 KB.
-	minWindowSize = 1 << 10
+	MinWindowSize = 1 << 10
+	MaxWindowSize = 1 << 30
 )
 
 var (
@@ -60,7 +61,7 @@ var (
 func newFrameDec(o decoderOptions) *frameDec {
 	d := frameDec{
 		o:             o,
-		maxWindowSize: 1 << 30,
+		maxWindowSize: MaxWindowSize,
 	}
 	if d.maxWindowSize > o.maxDecodedSize {
 		d.maxWindowSize = o.maxDecodedSize
@@ -193,14 +194,14 @@ func (d *frameDec) reset(br byteBuffer) error {
 			// When FCS_Field_Size is 2, the offset of 256 is added.
 			d.FrameContentSize = uint64(b[0]) | (uint64(b[1]) << 8) + 256
 		case 4:
-			d.FrameContentSize = uint64(b[0]) | (uint64(b[1]) << 8) | (uint64(b[2]) << 16) | (uint64(b[3] << 24))
+			d.FrameContentSize = uint64(b[0]) | (uint64(b[1]) << 8) | (uint64(b[2]) << 16) | (uint64(b[3]) << 24)
 		case 8:
 			d1 := uint32(b[0]) | (uint32(b[1]) << 8) | (uint32(b[2]) << 16) | (uint32(b[3]) << 24)
 			d2 := uint32(b[4]) | (uint32(b[5]) << 8) | (uint32(b[6]) << 16) | (uint32(b[7]) << 24)
 			d.FrameContentSize = uint64(d1) | (uint64(d2) << 32)
 		}
 		if debug {
-			println("field size bits:", v, "fcsSize:", fcsSize, "FrameContentSize:", d.FrameContentSize, hex.EncodeToString(b[:fcsSize]))
+			println("field size bits:", v, "fcsSize:", fcsSize, "FrameContentSize:", d.FrameContentSize, hex.EncodeToString(b[:fcsSize]), "singleseg:", d.SingleSegment, "window:", d.WindowSize)
 		}
 	}
 	// Move this to shared.
@@ -215,8 +216,8 @@ func (d *frameDec) reset(br byteBuffer) error {
 	if d.WindowSize == 0 && d.SingleSegment {
 		// We may not need window in this case.
 		d.WindowSize = d.FrameContentSize
-		if d.WindowSize < minWindowSize {
-			d.WindowSize = minWindowSize
+		if d.WindowSize < MinWindowSize {
+			d.WindowSize = MinWindowSize
 		}
 	}
 
@@ -225,7 +226,7 @@ func (d *frameDec) reset(br byteBuffer) error {
 		return ErrWindowSizeExceeded
 	}
 	// The minimum Window_Size is 1 KB.
-	if d.WindowSize < minWindowSize {
+	if d.WindowSize < MinWindowSize {
 		println("got window size: ", d.WindowSize)
 		return ErrWindowSizeTooSmall
 	}
@@ -309,7 +310,9 @@ func (d *frameDec) checkCRC() error {
 		}
 		return ErrCRCMismatch
 	}
-	println("CRC ok")
+	if debug {
+		println("CRC ok", tmp[:])
+	}
 	return nil
 }
 
@@ -411,6 +414,7 @@ func (d *frameDec) startDecoder(output chan decodeOutput) {
 		}
 		written += int64(len(r.b))
 		if d.SingleSegment && uint64(written) > d.FrameContentSize {
+			println("runDecoder: single segment and", uint64(written), ">", d.FrameContentSize)
 			r.err = ErrFrameSizeExceeded
 			output <- r
 			return
@@ -461,6 +465,7 @@ func (d *frameDec) runDecoder(dst []byte, dec *blockDec) ([]byte, error) {
 			break
 		}
 		if d.SingleSegment && uint64(len(d.history.b)) > d.o.maxDecodedSize {
+			println("runDecoder: single segment and", uint64(len(d.history.b)), ">", d.o.maxDecodedSize)
 			err = ErrFrameSizeExceeded
 			break
 		}
diff --git a/vendor/github.com/klauspost/compress/zstd/frameenc.go b/vendor/github.com/klauspost/compress/zstd/frameenc.go
index acac32527..4479cfe18 100644
--- a/vendor/github.com/klauspost/compress/zstd/frameenc.go
+++ b/vendor/github.com/klauspost/compress/zstd/frameenc.go
@@ -5,7 +5,6 @@
 package zstd
 
 import (
-	"errors"
 	"fmt"
 	"io"
 	"math"
@@ -49,9 +48,7 @@ func (f frameHeader) appendTo(dst []byte) ([]byte, error) {
 		windowLog := (bits.Len32(f.WindowSize-1) - winLogMin) << 3
 		dst = append(dst, uint8(windowLog))
 	}
-	if f.SingleSegment && f.ContentSize == 0 {
-		return nil, errors.New("single segment, but no size set")
-	}
+
 	switch fcs {
 	case 0:
 		if f.SingleSegment {
diff --git a/vendor/github.com/klauspost/compress/zstd/fse_encoder.go b/vendor/github.com/klauspost/compress/zstd/fse_encoder.go
index dfa6cf7ce..619836f52 100644
--- a/vendor/github.com/klauspost/compress/zstd/fse_encoder.go
+++ b/vendor/github.com/klauspost/compress/zstd/fse_encoder.go
@@ -502,13 +502,22 @@ func (s *fseEncoder) validateNorm() (err error) {
 // writeCount will write the normalized histogram count to header.
 // This is read back by readNCount.
 func (s *fseEncoder) writeCount(out []byte) ([]byte, error) {
+	if s.useRLE {
+		return append(out, s.rleVal), nil
+	}
+	if s.preDefined || s.reUsed {
+		// Never write predefined.
+		return out, nil
+	}
+
 	var (
 		tableLog  = s.actualTableLog
 		tableSize = 1 << tableLog
 		previous0 bool
 		charnum   uint16
 
-		maxHeaderSize = ((int(s.symbolLen) * int(tableLog)) >> 3) + 3
+		// maximum header size plus 2 extra bytes for final output if bitCount == 0.
+		maxHeaderSize = ((int(s.symbolLen) * int(tableLog)) >> 3) + 3 + 2
 
 		// Write Table Size
 		bitStream = uint32(tableLog - minEncTablelog)
@@ -516,15 +525,12 @@ func (s *fseEncoder) writeCount(out []byte) ([]byte, error) {
 		remaining = int16(tableSize + 1) /* +1 for extra accuracy */
 		threshold = int16(tableSize)
 		nbBits    = uint(tableLog + 1)
+		outP      = len(out)
 	)
-	if s.useRLE {
-		return append(out, s.rleVal), nil
+	if cap(out) < outP+maxHeaderSize {
+		out = append(out, make([]byte, maxHeaderSize*3)...)
+		out = out[:len(out)-maxHeaderSize*3]
 	}
-	if s.preDefined || s.reUsed {
-		// Never write predefined.
-		return out, nil
-	}
-	outP := len(out)
 	out = out[:outP+maxHeaderSize]
 
 	// stops at 1
@@ -594,11 +600,14 @@ func (s *fseEncoder) writeCount(out []byte) ([]byte, error) {
 		}
 	}
 
+	if outP+2 > len(out) {
+		return nil, fmt.Errorf("internal error: %d > %d, maxheader: %d, sl: %d, tl: %d, normcount: %v", outP+2, len(out), maxHeaderSize, s.symbolLen, int(tableLog), s.norm[:s.symbolLen])
+	}
 	out[outP] = byte(bitStream)
 	out[outP+1] = byte(bitStream >> 8)
 	outP += int((bitCount + 7) / 8)
 
-	if uint16(charnum) > s.symbolLen {
+	if charnum > s.symbolLen {
 		return nil, errors.New("internal error: charnum > s.symbolLen")
 	}
 	return out[:outP], nil
diff --git a/vendor/github.com/klauspost/compress/zstd/fse_predefined.go b/vendor/github.com/klauspost/compress/zstd/fse_predefined.go
index 5186de802..6c17dc17f 100644
--- a/vendor/github.com/klauspost/compress/zstd/fse_predefined.go
+++ b/vendor/github.com/klauspost/compress/zstd/fse_predefined.go
@@ -7,6 +7,7 @@ package zstd
 import (
 	"fmt"
 	"math"
+	"sync"
 )
 
 var (
@@ -69,85 +70,89 @@ func fillBase(dst []baseOffset, base uint32, bits ...uint8) {
 	}
 }
 
-func init() {
-	// Literals length codes
-	tmp := make([]baseOffset, 36)
-	for i := range tmp[:16] {
-		tmp[i] = baseOffset{
-			baseLine: uint32(i),
-			addBits:  0,
+var predef sync.Once
+
+func initPredefined() {
+	predef.Do(func() {
+		// Literals length codes
+		tmp := make([]baseOffset, 36)
+		for i := range tmp[:16] {
+			tmp[i] = baseOffset{
+				baseLine: uint32(i),
+				addBits:  0,
+			}
 		}
-	}
-	fillBase(tmp[16:], 16, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-	symbolTableX[tableLiteralLengths] = tmp
-
-	// Match length codes
-	tmp = make([]baseOffset, 53)
-	for i := range tmp[:32] {
-		tmp[i] = baseOffset{
-			// The transformation adds the 3 length.
-			baseLine: uint32(i) + 3,
-			addBits:  0,
-		}
-	}
-	fillBase(tmp[32:], 35, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
-	symbolTableX[tableMatchLengths] = tmp
-
-	// Offset codes
-	tmp = make([]baseOffset, maxOffsetBits+1)
-	tmp[1] = baseOffset{
-		baseLine: 1,
-		addBits:  1,
-	}
-	fillBase(tmp[2:], 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
-	symbolTableX[tableOffsets] = tmp
-
-	// Fill predefined tables and transform them.
-	// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#default-distributions
-	for i := range fsePredef[:] {
-		f := &fsePredef[i]
-		switch tableIndex(i) {
-		case tableLiteralLengths:
-			// https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L243
-			f.actualTableLog = 6
-			copy(f.norm[:], []int16{4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1,
-				2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1,
-				-1, -1, -1, -1})
-			f.symbolLen = 36
-		case tableOffsets:
-			// https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L281
-			f.actualTableLog = 5
-			copy(f.norm[:], []int16{
-				1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
-				1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1})
-			f.symbolLen = 29
-		case tableMatchLengths:
-			//https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L304
-			f.actualTableLog = 6
-			copy(f.norm[:], []int16{
-				1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
-				1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
-				1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1,
-				-1, -1, -1, -1, -1})
-			f.symbolLen = 53
+		fillBase(tmp[16:], 16, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
+		symbolTableX[tableLiteralLengths] = tmp
+
+		// Match length codes
+		tmp = make([]baseOffset, 53)
+		for i := range tmp[:32] {
+			tmp[i] = baseOffset{
+				// The transformation adds the 3 length.
+				baseLine: uint32(i) + 3,
+				addBits:  0,
+			}
 		}
-		if err := f.buildDtable(); err != nil {
-			panic(fmt.Errorf("building table %v: %v", tableIndex(i), err))
+		fillBase(tmp[32:], 35, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
+		symbolTableX[tableMatchLengths] = tmp
+
+		// Offset codes
+		tmp = make([]baseOffset, maxOffsetBits+1)
+		tmp[1] = baseOffset{
+			baseLine: 1,
+			addBits:  1,
 		}
-		if err := f.transform(symbolTableX[i]); err != nil {
-			panic(fmt.Errorf("building table %v: %v", tableIndex(i), err))
+		fillBase(tmp[2:], 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
+		symbolTableX[tableOffsets] = tmp
+
+		// Fill predefined tables and transform them.
+		// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#default-distributions
+		for i := range fsePredef[:] {
+			f := &fsePredef[i]
+			switch tableIndex(i) {
+			case tableLiteralLengths:
+				// https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L243
+				f.actualTableLog = 6
+				copy(f.norm[:], []int16{4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1,
+					2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1,
+					-1, -1, -1, -1})
+				f.symbolLen = 36
+			case tableOffsets:
+				// https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L281
+				f.actualTableLog = 5
+				copy(f.norm[:], []int16{
+					1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
+					1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1})
+				f.symbolLen = 29
+			case tableMatchLengths:
+				//https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L304
+				f.actualTableLog = 6
+				copy(f.norm[:], []int16{
+					1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
+					1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+					1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1,
+					-1, -1, -1, -1, -1})
+				f.symbolLen = 53
+			}
+			if err := f.buildDtable(); err != nil {
+				panic(fmt.Errorf("building table %v: %v", tableIndex(i), err))
+			}
+			if err := f.transform(symbolTableX[i]); err != nil {
+				panic(fmt.Errorf("building table %v: %v", tableIndex(i), err))
+			}
+			f.preDefined = true
+
+			// Create encoder as well
+			enc := &fsePredefEnc[i]
+			copy(enc.norm[:], f.norm[:])
+			enc.symbolLen = f.symbolLen
+			enc.actualTableLog = f.actualTableLog
+			if err := enc.buildCTable(); err != nil {
+				panic(fmt.Errorf("building encoding table %v: %v", tableIndex(i), err))
+			}
+			enc.setBits(bitTables[i])
+			enc.preDefined = true
 		}
-		f.preDefined = true
-
-		// Create encoder as well
-		enc := &fsePredefEnc[i]
-		copy(enc.norm[:], f.norm[:])
-		enc.symbolLen = f.symbolLen
-		enc.actualTableLog = f.actualTableLog
-		if err := enc.buildCTable(); err != nil {
-			panic(fmt.Errorf("building encoding table %v: %v", tableIndex(i), err))
-		}
-		enc.setBits(bitTables[i])
-		enc.preDefined = true
-	}
+	})
 }
diff --git a/vendor/github.com/klauspost/compress/zstd/snappy.go b/vendor/github.com/klauspost/compress/zstd/snappy.go
index e9e518570..a048818f9 100644
--- a/vendor/github.com/klauspost/compress/zstd/snappy.go
+++ b/vendor/github.com/klauspost/compress/zstd/snappy.go
@@ -80,6 +80,7 @@ type SnappyConverter struct {
 // If any error is detected on the Snappy stream it is returned.
 // The number of bytes written is returned.
 func (r *SnappyConverter) Convert(in io.Reader, w io.Writer) (int64, error) {
+	initPredefined()
 	r.err = nil
 	r.r = in
 	if r.block == nil {
diff --git a/vendor/github.com/klauspost/compress/zstd/zstd.go b/vendor/github.com/klauspost/compress/zstd/zstd.go
index b975954c1..57a8a2f5b 100644
--- a/vendor/github.com/klauspost/compress/zstd/zstd.go
+++ b/vendor/github.com/klauspost/compress/zstd/zstd.go
@@ -11,6 +11,7 @@ import (
 
 const debug = false
 const debugSequences = false
+const debugMatches = false
 
 // force encoder to use predefined tables.
 const forcePreDef = false