vendor: upgrade github.com/klauspost/compress from v1.11.3 to v1.11.4

go.mod

@@ -13,7 +13,7 @@ require (
 	github.com/aws/aws-sdk-go v1.36.12
 	github.com/cespare/xxhash/v2 v2.1.1
 	github.com/golang/snappy v0.0.2
-	github.com/klauspost/compress v1.11.3
+	github.com/klauspost/compress v1.11.4
 	github.com/valyala/fastjson v1.6.3
 	github.com/valyala/fastrand v1.0.0
 	github.com/valyala/fasttemplate v1.2.1

go.sum

@@ -149,8 +149,9 @@ github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/X
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/compress v1.10.7/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
 github.com/klauspost/compress v1.11.0/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
-github.com/klauspost/compress v1.11.3 h1:dB4Bn0tN3wdCzQxnS8r06kV74qN/TAfaIS0bVE8h3jc=
 github.com/klauspost/compress v1.11.3/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
+github.com/klauspost/compress v1.11.4 h1:kz40R/YWls3iqT9zX9AHN3WoVsrAWVyui5sxuLqiXqU=
+github.com/klauspost/compress v1.11.4/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
 github.com/kr/pretty v0.1.0 h1:L/CwN0zerZDmRFUapSPitk6f+Q3+0za1rQkzVuMiMFI=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=

vendor/github.com/klauspost/compress/zstd/README.md

@@ -24,22 +24,21 @@ Godoc Documentation: https://godoc.org/github.com/klauspost/compress/zstd
 ### Status: 
 
 STABLE - there may always be subtle bugs, a wide variety of content has been tested and the library is actively 
-used by several projects. This library is being continuously [fuzz-tested](https://github.com/klauspost/compress-fuzz),
+used by several projects. This library is being [fuzz-tested](https://github.com/klauspost/compress-fuzz) for all updates.
-kindly supplied by [fuzzit.dev](https://fuzzit.dev/).
 
 There may still be specific combinations of data types/size/settings that could lead to edge cases, 
 so as always, testing is recommended.  
 
 For now, a high speed (fastest) and medium-fast (default) compressor has been implemented. 
 
-The "Fastest" compression ratio is roughly equivalent to zstd level 1. 
+* The "Fastest" compression ratio is roughly equivalent to zstd level 1. 
-The "Default" compression ratio is roughly equivalent to zstd level 3 (default).
+* The "Default" compression ratio is roughly equivalent to zstd level 3 (default).
+* The "Better" compression ratio is roughly equivalent to zstd level 7.
+* The "Best" compression ratio is roughly equivalent to zstd level 11.
 
 In terms of speed, it is typically 2x as fast as the stdlib deflate/gzip in its fastest mode. 
 The compression ratio compared to stdlib is around level 3, but usually 3x as fast.
 
-Compared to cgo zstd, the speed is around level 3 (default), but compression slightly worse, between level 1&2.
-
  
 ### Usage
 
@@ -140,7 +139,7 @@ I have collected some speed examples to compare speed and compression against ot
 
 * `file` is the input file.
 * `out` is the compressor used. `zskp` is this package. `zstd` is the Datadog cgo library. `gzstd/gzkp` is gzip standard and this library.
-* `level` is the compression level used. For `zskp` level 1 is "fastest", level 2 is "default".
+* `level` is the compression level used. For `zskp` level 1 is "fastest", level 2 is "default"; 3 is "better", 4 is "best".
 * `insize`/`outsize` is the input/output size.
 * `millis` is the number of milliseconds used for compression.
 * `mb/s` is megabytes (2^20 bytes) per second.
@@ -154,11 +153,13 @@ file    out     level   insize      outsize     millis  mb/s
 silesia.tar zskp    1   211947520   73101992    643     313.87
 silesia.tar zskp    2   211947520   67504318    969     208.38
 silesia.tar zskp    3   211947520   65177448    1899    106.44
+silesia.tar zskp    4   211947520   61381950    8115    24.91
 
 cgo zstd:
 silesia.tar zstd    1   211947520   73605392    543     371.56
 silesia.tar zstd    3   211947520   66793289    864     233.68
 silesia.tar zstd    6   211947520   62916450    1913    105.66
+silesia.tar zstd    9   211947520   60212393    5063    39.92
 
 gzip, stdlib/this package:
 silesia.tar gzstd   1   211947520   80007735    1654    122.21
@@ -171,9 +172,11 @@ file        out     level   insize  outsize     millis  mb/s
 gob-stream  zskp    1   1911399616  235022249   3088    590.30
 gob-stream  zskp    2   1911399616  205669791   3786    481.34
 gob-stream  zskp    3   1911399616  185792019   9324    195.48
+gob-stream  zskp    4   1911399616  171537212   32113   56.76
 gob-stream  zstd    1   1911399616  249810424   2637    691.26
 gob-stream  zstd    3   1911399616  208192146   3490    522.31
 gob-stream  zstd    6   1911399616  193632038   6687    272.56
+gob-stream  zstd    9   1911399616  177620386   16175   112.70
 gob-stream  gzstd   1   1911399616  357382641   10251   177.82
 gob-stream  gzkp    1   1911399616  362156523   5695    320.08
 
@@ -185,9 +188,11 @@ file    out level   insize      outsize     millis  mb/s
 enwik9  zskp    1   1000000000  343848582   3609    264.18
 enwik9  zskp    2   1000000000  317276632   5746    165.97
 enwik9  zskp    3   1000000000  294540704   11725   81.34
+enwik9  zskp    4   1000000000  276609671   44029   21.66
 enwik9  zstd    1   1000000000  358072021   3110    306.65
 enwik9  zstd    3   1000000000  313734672   4784    199.35
 enwik9  zstd    6   1000000000  295138875   10290   92.68
+enwik9  zstd    9   1000000000  278348700   28549   33.40
 enwik9  gzstd   1   1000000000  382578136   9604    99.30
 enwik9  gzkp    1   1000000000  383825945   6544    145.73
 
@@ -198,9 +203,11 @@ file                        out level   insize      outsize     millis  mb/s
 github-june-2days-2019.json zskp    1   6273951764  699045015   10620   563.40
 github-june-2days-2019.json zskp    2   6273951764  617881763   11687   511.96
 github-june-2days-2019.json zskp    3   6273951764  537511906   29252   204.54
+github-june-2days-2019.json zskp    4   6273951764  512796117   97791   61.18
 github-june-2days-2019.json zstd    1   6273951764  766284037   8450    708.00
 github-june-2days-2019.json zstd    3   6273951764  661889476   10927   547.57
 github-june-2days-2019.json zstd    6   6273951764  642756859   22996   260.18
+github-june-2days-2019.json zstd    9   6273951764  601974523   52413   114.16
 github-june-2days-2019.json gzstd   1   6273951764  1164400847  29948   199.79
 github-june-2days-2019.json gzkp    1   6273951764  1128755542  19236   311.03
 
@@ -211,9 +218,11 @@ file                    out level   insize      outsize     millis  mb/s
 rawstudio-mint14.tar    zskp    1   8558382592  3667489370  20210   403.84
 rawstudio-mint14.tar    zskp    2   8558382592  3364592300  31873   256.07
 rawstudio-mint14.tar    zskp    3   8558382592  3224594213  71751   113.75
+rawstudio-mint14.tar    zskp    4   8558382592  3027332295  486243  16.79
 rawstudio-mint14.tar    zstd    1   8558382592  3609250104  17136   476.27
 rawstudio-mint14.tar    zstd    3   8558382592  3341679997  29262   278.92
 rawstudio-mint14.tar    zstd    6   8558382592  3235846406  77904   104.77
+rawstudio-mint14.tar    zstd    9   8558382592  3160778861  140946  57.91
 rawstudio-mint14.tar    gzstd   1   8558382592  3926257486  57722   141.40
 rawstudio-mint14.tar    gzkp    1   8558382592  3970463184  41749   195.49
 
@@ -224,9 +233,11 @@ file                    out level   insize      outsize     millis  mb/s
 nyc-taxi-data-10M.csv   zskp    1   3325605752  641339945   8925    355.35
 nyc-taxi-data-10M.csv   zskp    2   3325605752  591748091   11268   281.44
 nyc-taxi-data-10M.csv   zskp    3   3325605752  538490114   19880   159.53
+nyc-taxi-data-10M.csv   zskp    4   3325605752  495986829   89368   35.49
 nyc-taxi-data-10M.csv   zstd    1   3325605752  687399637   8233    385.18
 nyc-taxi-data-10M.csv   zstd    3   3325605752  598514411   10065   315.07
 nyc-taxi-data-10M.csv   zstd    6   3325605752  570522953   20038   158.27
+nyc-taxi-data-10M.csv   zstd    9   3325605752  517554797   64565   49.12
 nyc-taxi-data-10M.csv   gzstd   1   3325605752  928656485   23876   132.83
 nyc-taxi-data-10M.csv   gzkp    1   3325605752  924718719   16388   193.53
 ```

vendor/github.com/klauspost/compress/zstd/blockdec.go

@@ -613,7 +613,7 @@ func (b *blockDec) decodeCompressed(hist *history) error {
 	// Decode treeless literal block.
 	if litType == literalsBlockTreeless {
 		// TODO: We could send the history early WITHOUT the stream history.
-		//   This would allow decoding treeless literials before the byte history is available.
+		//   This would allow decoding treeless literals before the byte history is available.
 		//   Silencia stats: Treeless 4393, with: 32775, total: 37168, 11% treeless.
 		//   So not much obvious gain here.
 

vendor/github.com/klauspost/compress/zstd/blockenc.go

@@ -76,6 +76,7 @@ func (b *blockEnc) reset(prev *blockEnc) {
 	if prev != nil {
 		b.recentOffsets = prev.prevRecentOffsets
 	}
+	b.dictLitEnc = nil
 }
 
 // reset will reset the block for a new encode, but in the same stream,

vendor/github.com/klauspost/compress/zstd/decodeheader.go

@@ -0,0 +1,202 @@
+// Copyright 2020+ Klaus Post. All rights reserved.
+// License information can be found in the LICENSE file.
+
+package zstd
+
+import (
+	"bytes"
+	"errors"
+	"io"
+)
+
+// HeaderMaxSize is the maximum size of a Frame and Block Header.
+// If less is sent to Header.Decode it *may* still contain enough information.
+const HeaderMaxSize = 14 + 3
+
+// Header contains information about the first frame and block within that.
+type Header struct {
+	// Window Size the window of data to keep while decoding.
+	// Will only be set if HasFCS is false.
+	WindowSize uint64
+
+	// Frame content size.
+	// Expected size of the entire frame.
+	FrameContentSize uint64
+
+	// Dictionary ID.
+	// If 0, no dictionary.
+	DictionaryID uint32
+
+	// First block information.
+	FirstBlock struct {
+		// OK will be set if first block could be decoded.
+		OK bool
+
+		// Is this the last block of a frame?
+		Last bool
+
+		// Is the data compressed?
+		// If true CompressedSize will be populated.
+		// Unfortunately DecompressedSize cannot be determined
+		// without decoding the blocks.
+		Compressed bool
+
+		// DecompressedSize is the expected decompressed size of the block.
+		// Will be 0 if it cannot be determined.
+		DecompressedSize int
+
+		// CompressedSize of the data in the block.
+		// Does not include the block header.
+		// Will be equal to DecompressedSize if not Compressed.
+		CompressedSize int
+	}
+
+	// Skippable will be true if the frame is meant to be skipped.
+	// No other information will be populated.
+	Skippable bool
+
+	// If set there is a checksum present for the block content.
+	HasCheckSum bool
+
+	// If this is true FrameContentSize will have a valid value
+	HasFCS bool
+
+	SingleSegment bool
+}
+
+// Decode the header from the beginning of the stream.
+// This will decode the frame header and the first block header if enough bytes are provided.
+// It is recommended to provide at least HeaderMaxSize bytes.
+// If the frame header cannot be read an error will be returned.
+// If there isn't enough input, io.ErrUnexpectedEOF is returned.
+// The FirstBlock.OK will indicate if enough information was available to decode the first block header.
+func (h *Header) Decode(in []byte) error {
+	if len(in) < 4 {
+		return io.ErrUnexpectedEOF
+	}
+	b, in := in[:4], in[4:]
+	if !bytes.Equal(b, frameMagic) {
+		if !bytes.Equal(b[1:4], skippableFrameMagic) || b[0]&0xf0 != 0x50 {
+			return ErrMagicMismatch
+		}
+		*h = Header{Skippable: true}
+		return nil
+	}
+	if len(in) < 1 {
+		return io.ErrUnexpectedEOF
+	}
+
+	// Clear output
+	*h = Header{}
+	fhd, in := in[0], in[1:]
+	h.SingleSegment = fhd&(1<<5) != 0
+	h.HasCheckSum = fhd&(1<<2) != 0
+
+	if fhd&(1<<3) != 0 {
+		return errors.New("Reserved bit set on frame header")
+	}
+
+	// Read Window_Descriptor
+	// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#window_descriptor
+	if !h.SingleSegment {
+		if len(in) < 1 {
+			return io.ErrUnexpectedEOF
+		}
+		var wd byte
+		wd, in = in[0], in[1:]
+		windowLog := 10 + (wd >> 3)
+		windowBase := uint64(1) << windowLog
+		windowAdd := (windowBase / 8) * uint64(wd&0x7)
+		h.WindowSize = windowBase + windowAdd
+	}
+
+	// Read Dictionary_ID
+	// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#dictionary_id
+	if size := fhd & 3; size != 0 {
+		if size == 3 {
+			size = 4
+		}
+		if len(in) < int(size) {
+			return io.ErrUnexpectedEOF
+		}
+		b, in = in[:size], in[size:]
+		if b == nil {
+			return io.ErrUnexpectedEOF
+		}
+		switch size {
+		case 1:
+			h.DictionaryID = uint32(b[0])
+		case 2:
+			h.DictionaryID = uint32(b[0]) | (uint32(b[1]) << 8)
+		case 4:
+			h.DictionaryID = uint32(b[0]) | (uint32(b[1]) << 8) | (uint32(b[2]) << 16) | (uint32(b[3]) << 24)
+		}
+	}
+
+	// Read Frame_Content_Size
+	// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#frame_content_size
+	var fcsSize int
+	v := fhd >> 6
+	switch v {
+	case 0:
+		if h.SingleSegment {
+			fcsSize = 1
+		}
+	default:
+		fcsSize = 1 << v
+	}
+
+	if fcsSize > 0 {
+		h.HasFCS = true
+		if len(in) < fcsSize {
+			return io.ErrUnexpectedEOF
+		}
+		b, in = in[:fcsSize], in[fcsSize:]
+		if b == nil {
+			return io.ErrUnexpectedEOF
+		}
+		switch fcsSize {
+		case 1:
+			h.FrameContentSize = uint64(b[0])
+		case 2:
+			// When FCS_Field_Size is 2, the offset of 256 is added.
+			h.FrameContentSize = uint64(b[0]) | (uint64(b[1]) << 8) + 256
+		case 4:
+			h.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)
+			h.FrameContentSize = uint64(d1) | (uint64(d2) << 32)
+		}
+	}
+
+	// Frame Header done, we will not fail from now on.
+	if len(in) < 3 {
+		return nil
+	}
+	tmp, in := in[:3], in[3:]
+	bh := uint32(tmp[0]) | (uint32(tmp[1]) << 8) | (uint32(tmp[2]) << 16)
+	h.FirstBlock.Last = bh&1 != 0
+	blockType := blockType((bh >> 1) & 3)
+	// find size.
+	cSize := int(bh >> 3)
+	switch blockType {
+	case blockTypeReserved:
+		return nil
+	case blockTypeRLE:
+		h.FirstBlock.Compressed = true
+		h.FirstBlock.DecompressedSize = cSize
+		h.FirstBlock.CompressedSize = 1
+	case blockTypeCompressed:
+		h.FirstBlock.Compressed = true
+		h.FirstBlock.CompressedSize = cSize
+	case blockTypeRaw:
+		h.FirstBlock.DecompressedSize = cSize
+		h.FirstBlock.CompressedSize = cSize
+	default:
+		panic("Invalid block type")
+	}
+
+	h.FirstBlock.OK = true
+	return nil
+}

vendor/github.com/klauspost/compress/zstd/enc_best.go

@@ -0,0 +1,484 @@
+// Copyright 2019+ Klaus Post. All rights reserved.
+// License information can be found in the LICENSE file.
+// Based on work by Yann Collet, released under BSD License.
+
+package zstd
+
+import (
+	"fmt"
+	"math/bits"
+)
+
+const (
+	bestLongTableBits = 20                     // Bits used in the long match table
+	bestLongTableSize = 1 << bestLongTableBits // Size of the table
+
+	// Note: Increasing the short table bits or making the hash shorter
+	// can actually lead to compression degradation since it will 'steal' more from the
+	// long match table and match offsets are quite big.
+	// This greatly depends on the type of input.
+	bestShortTableBits = 16                      // Bits used in the short match table
+	bestShortTableSize = 1 << bestShortTableBits // Size of the table
+)
+
+// bestFastEncoder uses 2 tables, one for short matches (5 bytes) and one for long matches.
+// The long match table contains the previous entry with the same hash,
+// effectively making it a "chain" of length 2.
+// When we find a long match we choose between the two values and select the longest.
+// When we find a short match, after checking the long, we check if we can find a long at n+1
+// and that it is longer (lazy matching).
+type bestFastEncoder struct {
+	fastBase
+	table         [bestShortTableSize]prevEntry
+	longTable     [bestLongTableSize]prevEntry
+	dictTable     []prevEntry
+	dictLongTable []prevEntry
+}
+
+// Encode improves compression...
+func (e *bestFastEncoder) Encode(blk *blockEnc, src []byte) {
+	const (
+		// Input margin is the number of bytes we read (8)
+		// and the maximum we will read ahead (2)
+		inputMargin            = 8 + 4
+		minNonLiteralBlockSize = 16
+	)
+
+	// Protect against e.cur wraparound.
+	for e.cur >= bufferReset {
+		if len(e.hist) == 0 {
+			for i := range e.table[:] {
+				e.table[i] = prevEntry{}
+			}
+			for i := range e.longTable[:] {
+				e.longTable[i] = prevEntry{}
+			}
+			e.cur = e.maxMatchOff
+			break
+		}
+		// Shift down everything in the table that isn't already too far away.
+		minOff := e.cur + int32(len(e.hist)) - e.maxMatchOff
+		for i := range e.table[:] {
+			v := e.table[i].offset
+			v2 := e.table[i].prev
+			if v < minOff {
+				v = 0
+				v2 = 0
+			} else {
+				v = v - e.cur + e.maxMatchOff
+				if v2 < minOff {
+					v2 = 0
+				} else {
+					v2 = v2 - e.cur + e.maxMatchOff
+				}
+			}
+			e.table[i] = prevEntry{
+				offset: v,
+				prev:   v2,
+			}
+		}
+		for i := range e.longTable[:] {
+			v := e.longTable[i].offset
+			v2 := e.longTable[i].prev
+			if v < minOff {
+				v = 0
+				v2 = 0
+			} else {
+				v = v - e.cur + e.maxMatchOff
+				if v2 < minOff {
+					v2 = 0
+				} else {
+					v2 = v2 - e.cur + e.maxMatchOff
+				}
+			}
+			e.longTable[i] = prevEntry{
+				offset: v,
+				prev:   v2,
+			}
+		}
+		e.cur = e.maxMatchOff
+		break
+	}
+
+	s := e.addBlock(src)
+	blk.size = len(src)
+	if len(src) < minNonLiteralBlockSize {
+		blk.extraLits = len(src)
+		blk.literals = blk.literals[:len(src)]
+		copy(blk.literals, src)
+		return
+	}
+
+	// Override src
+	src = e.hist
+	sLimit := int32(len(src)) - inputMargin
+	const kSearchStrength = 12
+
+	// nextEmit is where in src the next emitLiteral should start from.
+	nextEmit := s
+	cv := load6432(src, s)
+
+	// Relative offsets
+	offset1 := int32(blk.recentOffsets[0])
+	offset2 := int32(blk.recentOffsets[1])
+	offset3 := int32(blk.recentOffsets[2])
+
+	addLiterals := func(s *seq, until int32) {
+		if until == nextEmit {
+			return
+		}
+		blk.literals = append(blk.literals, src[nextEmit:until]...)
+		s.litLen = uint32(until - nextEmit)
+	}
+	_ = addLiterals
+
+	if debug {
+		println("recent offsets:", blk.recentOffsets)
+	}
+
+encodeLoop:
+	for {
+		// We allow the encoder to optionally turn off repeat offsets across blocks
+		canRepeat := len(blk.sequences) > 2
+
+		if debugAsserts && canRepeat && offset1 == 0 {
+			panic("offset0 was 0")
+		}
+
+		type match struct {
+			offset int32
+			s      int32
+			length int32
+			rep    int32
+		}
+		matchAt := func(offset int32, s int32, first uint32, rep int32) match {
+			if s-offset >= e.maxMatchOff || load3232(src, offset) != first {
+				return match{offset: offset, s: s}
+			}
+			return match{offset: offset, s: s, length: 4 + e.matchlen(s+4, offset+4, src), rep: rep}
+		}
+
+		bestOf := func(a, b match) match {
+			aScore := b.s - a.s + a.length
+			bScore := a.s - b.s + b.length
+			if a.rep < 0 {
+				aScore = aScore - int32(bits.Len32(uint32(a.offset)))/8
+			}
+			if b.rep < 0 {
+				bScore = bScore - int32(bits.Len32(uint32(b.offset)))/8
+			}
+			if aScore >= bScore {
+				return a
+			}
+			return b
+		}
+		const goodEnough = 100
+
+		nextHashL := hash8(cv, bestLongTableBits)
+		nextHashS := hash4x64(cv, bestShortTableBits)
+		candidateL := e.longTable[nextHashL]
+		candidateS := e.table[nextHashS]
+
+		best := bestOf(matchAt(candidateL.offset-e.cur, s, uint32(cv), -1), matchAt(candidateL.prev-e.cur, s, uint32(cv), -1))
+		best = bestOf(best, matchAt(candidateS.offset-e.cur, s, uint32(cv), -1))
+		best = bestOf(best, matchAt(candidateS.prev-e.cur, s, uint32(cv), -1))
+		if canRepeat && best.length < goodEnough {
+			best = bestOf(best, matchAt(s-offset1+1, s+1, uint32(cv>>8), 1))
+			best = bestOf(best, matchAt(s-offset2+1, s+1, uint32(cv>>8), 2))
+			best = bestOf(best, matchAt(s-offset3+1, s+1, uint32(cv>>8), 3))
+			best = bestOf(best, matchAt(s-offset1+3, s+3, uint32(cv>>24), 1))
+			best = bestOf(best, matchAt(s-offset2+3, s+3, uint32(cv>>24), 2))
+			best = bestOf(best, matchAt(s-offset3+3, s+3, uint32(cv>>24), 3))
+		}
+		// Load next and check...
+		e.longTable[nextHashL] = prevEntry{offset: s + e.cur, prev: candidateL.offset}
+		e.table[nextHashS] = prevEntry{offset: s + e.cur, prev: candidateS.offset}
+
+		// Look far ahead, unless we have a really long match already...
+		if best.length < goodEnough {
+			// No match found, move forward on input, no need to check forward...
+			if best.length < 4 {
+				s += 1 + (s-nextEmit)>>(kSearchStrength-1)
+				if s >= sLimit {
+					break encodeLoop
+				}
+				cv = load6432(src, s)
+				continue
+			}
+
+			s++
+			candidateS = e.table[hash4x64(cv>>8, bestShortTableBits)]
+			cv = load6432(src, s)
+			cv2 := load6432(src, s+1)
+			candidateL = e.longTable[hash8(cv, bestLongTableBits)]
+			candidateL2 := e.longTable[hash8(cv2, bestLongTableBits)]
+
+			best = bestOf(best, matchAt(candidateS.offset-e.cur, s, uint32(cv), -1))
+			best = bestOf(best, matchAt(candidateL.offset-e.cur, s, uint32(cv), -1))
+			best = bestOf(best, matchAt(candidateL.prev-e.cur, s, uint32(cv), -1))
+			best = bestOf(best, matchAt(candidateL2.offset-e.cur, s+1, uint32(cv2), -1))
+			best = bestOf(best, matchAt(candidateL2.prev-e.cur, s+1, uint32(cv2), -1))
+		}
+
+		// We have a match, we can store the forward value
+		if best.rep > 0 {
+			s = best.s
+			var seq seq
+			seq.matchLen = uint32(best.length - zstdMinMatch)
+
+			// We might be able to match backwards.
+			// Extend as long as we can.
+			start := best.s
+			// We end the search early, so we don't risk 0 literals
+			// and have to do special offset treatment.
+			startLimit := nextEmit + 1
+
+			tMin := s - e.maxMatchOff
+			if tMin < 0 {
+				tMin = 0
+			}
+			repIndex := best.offset
+			for repIndex > tMin && start > startLimit && src[repIndex-1] == src[start-1] && seq.matchLen < maxMatchLength-zstdMinMatch-1 {
+				repIndex--
+				start--
+				seq.matchLen++
+			}
+			addLiterals(&seq, start)
+
+			// rep 0
+			seq.offset = uint32(best.rep)
+			if debugSequences {
+				println("repeat sequence", seq, "next s:", s)
+			}
+			blk.sequences = append(blk.sequences, seq)
+
+			// Index match start+1 (long) -> s - 1
+			index0 := s
+			s = best.s + best.length
+
+			nextEmit = s
+			if s >= sLimit {
+				if debug {
+					println("repeat ended", s, best.length)
+
+				}
+				break encodeLoop
+			}
+			// Index skipped...
+			off := index0 + e.cur
+			for index0 < s-1 {
+				cv0 := load6432(src, index0)
+				h0 := hash8(cv0, bestLongTableBits)
+				h1 := hash4x64(cv0, bestShortTableBits)
+				e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
+				e.table[h1] = prevEntry{offset: off, prev: e.table[h1].offset}
+				off++
+				index0++
+			}
+			switch best.rep {
+			case 2:
+				offset1, offset2 = offset2, offset1
+			case 3:
+				offset1, offset2, offset3 = offset3, offset1, offset2
+			}
+			cv = load6432(src, s)
+			continue
+		}
+
+		// A 4-byte match has been found. Update recent offsets.
+		// We'll later see if more than 4 bytes.
+		s = best.s
+		t := best.offset
+		offset1, offset2, offset3 = s-t, offset1, offset2
+
+		if debugAsserts && s <= t {
+			panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
+		}
+
+		if debugAsserts && canRepeat && int(offset1) > len(src) {
+			panic("invalid offset")
+		}
+
+		// Extend the n-byte match as long as possible.
+		l := best.length
+
+		// Extend backwards
+		tMin := s - e.maxMatchOff
+		if tMin < 0 {
+			tMin = 0
+		}
+		for t > tMin && s > nextEmit && src[t-1] == src[s-1] && l < maxMatchLength {
+			s--
+			t--
+			l++
+		}
+
+		// Write our sequence
+		var seq seq
+		seq.litLen = uint32(s - nextEmit)
+		seq.matchLen = uint32(l - zstdMinMatch)
+		if seq.litLen > 0 {
+			blk.literals = append(blk.literals, src[nextEmit:s]...)
+		}
+		seq.offset = uint32(s-t) + 3
+		s += l
+		if debugSequences {
+			println("sequence", seq, "next s:", s)
+		}
+		blk.sequences = append(blk.sequences, seq)
+		nextEmit = s
+		if s >= sLimit {
+			break encodeLoop
+		}
+
+		// Index match start+1 (long) -> s - 1
+		index0 := s - l + 1
+		// every entry
+		for index0 < s-1 {
+			cv0 := load6432(src, index0)
+			h0 := hash8(cv0, bestLongTableBits)
+			h1 := hash4x64(cv0, bestShortTableBits)
+			off := index0 + e.cur
+			e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
+			e.table[h1] = prevEntry{offset: off, prev: e.table[h1].offset}
+			index0++
+		}
+
+		cv = load6432(src, s)
+		if !canRepeat {
+			continue
+		}
+
+		// Check offset 2
+		for {
+			o2 := s - offset2
+			if load3232(src, o2) != uint32(cv) {
+				// Do regular search
+				break
+			}
+
+			// Store this, since we have it.
+			nextHashS := hash4x64(cv, bestShortTableBits)
+			nextHashL := hash8(cv, bestLongTableBits)
+
+			// We have at least 4 byte match.
+			// No need to check backwards. We come straight from a match
+			l := 4 + e.matchlen(s+4, o2+4, src)
+
+			e.longTable[nextHashL] = prevEntry{offset: s + e.cur, prev: e.longTable[nextHashL].offset}
+			e.table[nextHashS] = prevEntry{offset: s + e.cur, prev: e.table[nextHashS].offset}
+			seq.matchLen = uint32(l) - zstdMinMatch
+			seq.litLen = 0
+
+			// Since litlen is always 0, this is offset 1.
+			seq.offset = 1
+			s += l
+			nextEmit = s
+			if debugSequences {
+				println("sequence", seq, "next s:", s)
+			}
+			blk.sequences = append(blk.sequences, seq)
+
+			// Swap offset 1 and 2.
+			offset1, offset2 = offset2, offset1
+			if s >= sLimit {
+				// Finished
+				break encodeLoop
+			}
+			cv = load6432(src, s)
+		}
+	}
+
+	if int(nextEmit) < len(src) {
+		blk.literals = append(blk.literals, src[nextEmit:]...)
+		blk.extraLits = len(src) - int(nextEmit)
+	}
+	blk.recentOffsets[0] = uint32(offset1)
+	blk.recentOffsets[1] = uint32(offset2)
+	blk.recentOffsets[2] = uint32(offset3)
+	if debug {
+		println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
+	}
+}
+
+// EncodeNoHist will encode a block with no history and no following blocks.
+// Most notable difference is that src will not be copied for history and
+// we do not need to check for max match length.
+func (e *bestFastEncoder) EncodeNoHist(blk *blockEnc, src []byte) {
+	e.Encode(blk, src)
+}
+
+// ResetDict will reset and set a dictionary if not nil
+func (e *bestFastEncoder) Reset(d *dict, singleBlock bool) {
+	e.resetBase(d, singleBlock)
+	if d == nil {
+		return
+	}
+	// Init or copy dict table
+	if len(e.dictTable) != len(e.table) || d.id != e.lastDictID {
+		if len(e.dictTable) != len(e.table) {
+			e.dictTable = make([]prevEntry, len(e.table))
+		}
+		end := int32(len(d.content)) - 8 + e.maxMatchOff
+		for i := e.maxMatchOff; i < end; i += 4 {
+			const hashLog = bestShortTableBits
+
+			cv := load6432(d.content, i-e.maxMatchOff)
+			nextHash := hash4x64(cv, hashLog)      // 0 -> 4
+			nextHash1 := hash4x64(cv>>8, hashLog)  // 1 -> 5
+			nextHash2 := hash4x64(cv>>16, hashLog) // 2 -> 6
+			nextHash3 := hash4x64(cv>>24, hashLog) // 3 -> 7
+			e.dictTable[nextHash] = prevEntry{
+				prev:   e.dictTable[nextHash].offset,
+				offset: i,
+			}
+			e.dictTable[nextHash1] = prevEntry{
+				prev:   e.dictTable[nextHash1].offset,
+				offset: i + 1,
+			}
+			e.dictTable[nextHash2] = prevEntry{
+				prev:   e.dictTable[nextHash2].offset,
+				offset: i + 2,
+			}
+			e.dictTable[nextHash3] = prevEntry{
+				prev:   e.dictTable[nextHash3].offset,
+				offset: i + 3,
+			}
+		}
+		e.lastDictID = d.id
+	}
+
+	// Init or copy dict table
+	if len(e.dictLongTable) != len(e.longTable) || d.id != e.lastDictID {
+		if len(e.dictLongTable) != len(e.longTable) {
+			e.dictLongTable = make([]prevEntry, len(e.longTable))
+		}
+		if len(d.content) >= 8 {
+			cv := load6432(d.content, 0)
+			h := hash8(cv, bestLongTableBits)
+			e.dictLongTable[h] = prevEntry{
+				offset: e.maxMatchOff,
+				prev:   e.dictLongTable[h].offset,
+			}
+
+			end := int32(len(d.content)) - 8 + e.maxMatchOff
+			off := 8 // First to read
+			for i := e.maxMatchOff + 1; i < end; i++ {
+				cv = cv>>8 | (uint64(d.content[off]) << 56)
+				h := hash8(cv, bestLongTableBits)
+				e.dictLongTable[h] = prevEntry{
+					offset: i,
+					prev:   e.dictLongTable[h].offset,
+				}
+				off++
+			}
+		}
+		e.lastDictID = d.id
+	}
+	// Reset table to initial state
+	copy(e.longTable[:], e.dictLongTable)
+
+	e.cur = e.maxMatchOff
+	// Reset table to initial state
+	copy(e.table[:], e.dictTable)
+}

vendor/github.com/klauspost/compress/zstd/encoder_options.go

@@ -47,6 +47,8 @@ func (o encoderOptions) encoder() encoder {
 		return &doubleFastEncoder{fastEncoder: fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize)}}}
 	case SpeedBetterCompression:
 		return &betterFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize)}}
+	case SpeedBestCompression:
+		return &bestFastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize)}}
 	case SpeedFastest:
 		return &fastEncoder{fastBase: fastBase{maxMatchOff: int32(o.windowSize)}}
 	}
@@ -143,20 +145,20 @@ const (
 	// By using this, notice that CPU usage may go up in the future.
 	SpeedBetterCompression
 
+	// SpeedBestCompression will choose the best available compression option.
+	// This will offer the best compression no matter the CPU cost.
+	SpeedBestCompression
+
 	// speedLast should be kept as the last actual compression option.
 	// The is not for external usage, but is used to keep track of the valid options.
 	speedLast
-
-	// SpeedBestCompression will choose the best available compression option.
-	// For now this is not implemented.
-	SpeedBestCompression = SpeedBetterCompression
 )
 
 // EncoderLevelFromString will convert a string representation of an encoding level back
 // to a compression level. The compare is not case sensitive.
 // If the string wasn't recognized, (false, SpeedDefault) will be returned.
 func EncoderLevelFromString(s string) (bool, EncoderLevel) {
-	for l := EncoderLevel(speedNotSet + 1); l < speedLast; l++ {
+	for l := speedNotSet + 1; l < speedLast; l++ {
 		if strings.EqualFold(s, l.String()) {
 			return true, l
 		}
@@ -173,7 +175,9 @@ func EncoderLevelFromZstd(level int) EncoderLevel {
 		return SpeedFastest
 	case level >= 3 && level < 6:
 		return SpeedDefault
-	case level > 5:
+	case level >= 6 && level < 10:
+		return SpeedBetterCompression
+	case level >= 10:
 		return SpeedBetterCompression
 	}
 	return SpeedDefault
@@ -188,6 +192,8 @@ func (e EncoderLevel) String() string {
 		return "default"
 	case SpeedBetterCompression:
 		return "better"
+	case SpeedBestCompression:
+		return "best"
 	default:
 		return "invalid"
 	}
@@ -209,6 +215,8 @@ func WithEncoderLevel(l EncoderLevel) EOption {
 				o.windowSize = 8 << 20
 			case SpeedBetterCompression:
 				o.windowSize = 16 << 20
+			case SpeedBestCompression:
+				o.windowSize = 32 << 20
 			}
 		}
 		if !o.customALEntropy {

vendor/modules.txt

@@ -88,7 +88,7 @@ github.com/jmespath/go-jmespath
 github.com/jstemmer/go-junit-report
 github.com/jstemmer/go-junit-report/formatter
 github.com/jstemmer/go-junit-report/parser
-# github.com/klauspost/compress v1.11.3
+# github.com/klauspost/compress v1.11.4
 github.com/klauspost/compress/flate
 github.com/klauspost/compress/fse
 github.com/klauspost/compress/gzip