Upgrade versions of vendored libs
This commit is contained in:
713
vendor/github.com/klauspost/compress/zstd/enc_better.go
generated
vendored
713
vendor/github.com/klauspost/compress/zstd/enc_better.go
generated
vendored
@@ -9,6 +9,7 @@ import "fmt"
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const (
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betterLongTableBits = 19 // Bits used in the long match table
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betterLongTableSize = 1 << betterLongTableBits // Size of the table
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betterLongLen = 8 // Bytes used for table hash
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// Note: Increasing the short table bits or making the hash shorter
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// can actually lead to compression degradation since it will 'steal' more from the
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@@ -16,6 +17,13 @@ const (
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// This greatly depends on the type of input.
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betterShortTableBits = 13 // Bits used in the short match table
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betterShortTableSize = 1 << betterShortTableBits // Size of the table
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betterShortLen = 5 // Bytes used for table hash
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betterLongTableShardCnt = 1 << (betterLongTableBits - dictShardBits) // Number of shards in the table
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betterLongTableShardSize = betterLongTableSize / betterLongTableShardCnt // Size of an individual shard
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betterShortTableShardCnt = 1 << (betterShortTableBits - dictShardBits) // Number of shards in the table
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betterShortTableShardSize = betterShortTableSize / betterShortTableShardCnt // Size of an individual shard
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)
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type prevEntry struct {
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@@ -31,10 +39,17 @@ type prevEntry struct {
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// and that it is longer (lazy matching).
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type betterFastEncoder struct {
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fastBase
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table [betterShortTableSize]tableEntry
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longTable [betterLongTableSize]prevEntry
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dictTable []tableEntry
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dictLongTable []prevEntry
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table [betterShortTableSize]tableEntry
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longTable [betterLongTableSize]prevEntry
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}
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type betterFastEncoderDict struct {
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betterFastEncoder
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dictTable []tableEntry
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dictLongTable []prevEntry
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shortTableShardDirty [betterShortTableShardCnt]bool
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longTableShardDirty [betterLongTableShardCnt]bool
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allDirty bool
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}
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// Encode improves compression...
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@@ -125,7 +140,7 @@ func (e *betterFastEncoder) Encode(blk *blockEnc, src []byte) {
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blk.literals = append(blk.literals, src[nextEmit:until]...)
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s.litLen = uint32(until - nextEmit)
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}
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if debug {
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if debugEncoder {
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println("recent offsets:", blk.recentOffsets)
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}
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@@ -141,8 +156,8 @@ encodeLoop:
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panic("offset0 was 0")
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}
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nextHashS := hash5(cv, betterShortTableBits)
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nextHashL := hash8(cv, betterLongTableBits)
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nextHashL := hashLen(cv, betterLongTableBits, betterLongLen)
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nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
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candidateL := e.longTable[nextHashL]
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candidateS := e.table[nextHashS]
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@@ -191,7 +206,7 @@ encodeLoop:
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nextEmit = s
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if s >= sLimit {
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if debug {
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if debugEncoder {
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println("repeat ended", s, lenght)
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}
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@@ -201,10 +216,10 @@ encodeLoop:
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for index0 < s-1 {
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cv0 := load6432(src, index0)
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cv1 := cv0 >> 8
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h0 := hash8(cv0, betterLongTableBits)
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h0 := hashLen(cv0, betterLongTableBits, betterLongLen)
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off := index0 + e.cur
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e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
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e.table[hash5(cv1, betterShortTableBits)] = tableEntry{offset: off + 1, val: uint32(cv1)}
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e.table[hashLen(cv1, betterShortTableBits, betterShortLen)] = tableEntry{offset: off + 1, val: uint32(cv1)}
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index0 += 2
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}
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cv = load6432(src, s)
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@@ -251,7 +266,7 @@ encodeLoop:
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s += lenght + repOff2
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nextEmit = s
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if s >= sLimit {
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if debug {
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if debugEncoder {
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println("repeat ended", s, lenght)
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}
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@@ -262,10 +277,10 @@ encodeLoop:
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for index0 < s-1 {
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cv0 := load6432(src, index0)
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cv1 := cv0 >> 8
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h0 := hash8(cv0, betterLongTableBits)
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h0 := hashLen(cv0, betterLongTableBits, betterLongLen)
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off := index0 + e.cur
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e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
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e.table[hash5(cv1, betterShortTableBits)] = tableEntry{offset: off + 1, val: uint32(cv1)}
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e.table[hashLen(cv1, betterShortTableBits, betterShortLen)] = tableEntry{offset: off + 1, val: uint32(cv1)}
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index0 += 2
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}
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cv = load6432(src, s)
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@@ -340,7 +355,7 @@ encodeLoop:
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// See if we can find a long match at s+1
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const checkAt = 1
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cv := load6432(src, s+checkAt)
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nextHashL = hash8(cv, betterLongTableBits)
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nextHashL = hashLen(cv, betterLongTableBits, betterLongLen)
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candidateL = e.longTable[nextHashL]
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coffsetL = candidateL.offset - e.cur
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@@ -399,8 +414,50 @@ encodeLoop:
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cv = load6432(src, s)
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}
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// A 4-byte match has been found. Update recent offsets.
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// We'll later see if more than 4 bytes.
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// Try to find a better match by searching for a long match at the end of the current best match
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if s+matched < sLimit {
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// Allow some bytes at the beginning to mismatch.
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// Sweet spot is around 3 bytes, but depends on input.
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// The skipped bytes are tested in Extend backwards,
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// and still picked up as part of the match if they do.
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const skipBeginning = 3
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nextHashL := hashLen(load6432(src, s+matched), betterLongTableBits, betterLongLen)
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s2 := s + skipBeginning
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cv := load3232(src, s2)
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candidateL := e.longTable[nextHashL]
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coffsetL := candidateL.offset - e.cur - matched + skipBeginning
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if coffsetL >= 0 && coffsetL < s2 && s2-coffsetL < e.maxMatchOff && cv == load3232(src, coffsetL) {
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// Found a long match, at least 4 bytes.
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matchedNext := e.matchlen(s2+4, coffsetL+4, src) + 4
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if matchedNext > matched {
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t = coffsetL
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s = s2
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matched = matchedNext
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if debugMatches {
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println("long match at end-of-match")
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}
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}
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}
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// Check prev long...
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if true {
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coffsetL = candidateL.prev - e.cur - matched + skipBeginning
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if coffsetL >= 0 && coffsetL < s2 && s2-coffsetL < e.maxMatchOff && cv == load3232(src, coffsetL) {
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// Found a long match, at least 4 bytes.
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matchedNext := e.matchlen(s2+4, coffsetL+4, src) + 4
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if matchedNext > matched {
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t = coffsetL
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s = s2
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matched = matchedNext
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if debugMatches {
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println("prev long match at end-of-match")
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}
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}
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}
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}
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}
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// A match has been found. Update recent offsets.
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offset2 = offset1
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offset1 = s - t
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@@ -449,10 +506,10 @@ encodeLoop:
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for index0 < s-1 {
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cv0 := load6432(src, index0)
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cv1 := cv0 >> 8
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h0 := hash8(cv0, betterLongTableBits)
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h0 := hashLen(cv0, betterLongTableBits, betterLongLen)
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off := index0 + e.cur
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e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
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e.table[hash5(cv1, betterShortTableBits)] = tableEntry{offset: off + 1, val: uint32(cv1)}
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e.table[hashLen(cv1, betterShortTableBits, betterShortLen)] = tableEntry{offset: off + 1, val: uint32(cv1)}
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index0 += 2
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}
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@@ -470,8 +527,8 @@ encodeLoop:
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}
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// Store this, since we have it.
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nextHashS := hash5(cv, betterShortTableBits)
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nextHashL := hash8(cv, betterLongTableBits)
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nextHashL := hashLen(cv, betterLongTableBits, betterLongLen)
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nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
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// We have at least 4 byte match.
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// No need to check backwards. We come straight from a match
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@@ -507,7 +564,7 @@ encodeLoop:
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}
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blk.recentOffsets[0] = uint32(offset1)
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blk.recentOffsets[1] = uint32(offset2)
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if debug {
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if debugEncoder {
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println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
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}
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}
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@@ -516,11 +573,543 @@ encodeLoop:
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// Most notable difference is that src will not be copied for history and
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// we do not need to check for max match length.
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func (e *betterFastEncoder) EncodeNoHist(blk *blockEnc, src []byte) {
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e.ensureHist(len(src))
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e.Encode(blk, src)
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}
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// Encode improves compression...
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func (e *betterFastEncoderDict) Encode(blk *blockEnc, src []byte) {
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const (
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// Input margin is the number of bytes we read (8)
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// and the maximum we will read ahead (2)
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inputMargin = 8 + 2
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minNonLiteralBlockSize = 16
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)
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// Protect against e.cur wraparound.
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for e.cur >= bufferReset {
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if len(e.hist) == 0 {
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for i := range e.table[:] {
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e.table[i] = tableEntry{}
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}
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for i := range e.longTable[:] {
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e.longTable[i] = prevEntry{}
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}
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e.cur = e.maxMatchOff
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e.allDirty = true
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break
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}
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// Shift down everything in the table that isn't already too far away.
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minOff := e.cur + int32(len(e.hist)) - e.maxMatchOff
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for i := range e.table[:] {
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v := e.table[i].offset
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if v < minOff {
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v = 0
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} else {
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v = v - e.cur + e.maxMatchOff
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}
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e.table[i].offset = v
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}
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for i := range e.longTable[:] {
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v := e.longTable[i].offset
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v2 := e.longTable[i].prev
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if v < minOff {
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v = 0
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v2 = 0
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} else {
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v = v - e.cur + e.maxMatchOff
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if v2 < minOff {
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v2 = 0
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} else {
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v2 = v2 - e.cur + e.maxMatchOff
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}
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}
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e.longTable[i] = prevEntry{
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offset: v,
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prev: v2,
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}
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}
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e.allDirty = true
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e.cur = e.maxMatchOff
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break
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}
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s := e.addBlock(src)
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blk.size = len(src)
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if len(src) < minNonLiteralBlockSize {
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blk.extraLits = len(src)
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blk.literals = blk.literals[:len(src)]
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copy(blk.literals, src)
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return
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}
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// Override src
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src = e.hist
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sLimit := int32(len(src)) - inputMargin
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// stepSize is the number of bytes to skip on every main loop iteration.
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// It should be >= 1.
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const stepSize = 1
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const kSearchStrength = 9
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// nextEmit is where in src the next emitLiteral should start from.
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nextEmit := s
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cv := load6432(src, s)
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// Relative offsets
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offset1 := int32(blk.recentOffsets[0])
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offset2 := int32(blk.recentOffsets[1])
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addLiterals := func(s *seq, until int32) {
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if until == nextEmit {
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return
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}
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blk.literals = append(blk.literals, src[nextEmit:until]...)
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s.litLen = uint32(until - nextEmit)
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}
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if debugEncoder {
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println("recent offsets:", blk.recentOffsets)
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}
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encodeLoop:
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for {
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var t int32
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// We allow the encoder to optionally turn off repeat offsets across blocks
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canRepeat := len(blk.sequences) > 2
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var matched int32
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for {
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if debugAsserts && canRepeat && offset1 == 0 {
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panic("offset0 was 0")
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}
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nextHashL := hashLen(cv, betterLongTableBits, betterLongLen)
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nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
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candidateL := e.longTable[nextHashL]
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candidateS := e.table[nextHashS]
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const repOff = 1
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repIndex := s - offset1 + repOff
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off := s + e.cur
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e.longTable[nextHashL] = prevEntry{offset: off, prev: candidateL.offset}
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e.markLongShardDirty(nextHashL)
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e.table[nextHashS] = tableEntry{offset: off, val: uint32(cv)}
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e.markShortShardDirty(nextHashS)
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if canRepeat {
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if repIndex >= 0 && load3232(src, repIndex) == uint32(cv>>(repOff*8)) {
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// Consider history as well.
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var seq seq
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lenght := 4 + e.matchlen(s+4+repOff, repIndex+4, src)
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seq.matchLen = uint32(lenght - zstdMinMatch)
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// We might be able to match backwards.
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// Extend as long as we can.
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start := s + repOff
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// We end the search early, so we don't risk 0 literals
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// and have to do special offset treatment.
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startLimit := nextEmit + 1
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tMin := s - e.maxMatchOff
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if tMin < 0 {
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tMin = 0
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}
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for repIndex > tMin && start > startLimit && src[repIndex-1] == src[start-1] && seq.matchLen < maxMatchLength-zstdMinMatch-1 {
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repIndex--
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start--
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seq.matchLen++
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}
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addLiterals(&seq, start)
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// rep 0
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seq.offset = 1
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if debugSequences {
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println("repeat sequence", seq, "next s:", s)
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}
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blk.sequences = append(blk.sequences, seq)
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// Index match start+1 (long) -> s - 1
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index0 := s + repOff
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s += lenght + repOff
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nextEmit = s
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if s >= sLimit {
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if debugEncoder {
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println("repeat ended", s, lenght)
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}
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break encodeLoop
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}
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// Index skipped...
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for index0 < s-1 {
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cv0 := load6432(src, index0)
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cv1 := cv0 >> 8
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h0 := hashLen(cv0, betterLongTableBits, betterLongLen)
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off := index0 + e.cur
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e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
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e.markLongShardDirty(h0)
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h1 := hashLen(cv1, betterShortTableBits, betterShortLen)
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e.table[h1] = tableEntry{offset: off + 1, val: uint32(cv1)}
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e.markShortShardDirty(h1)
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index0 += 2
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}
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cv = load6432(src, s)
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continue
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}
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const repOff2 = 1
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// We deviate from the reference encoder and also check offset 2.
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// Still slower and not much better, so disabled.
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// repIndex = s - offset2 + repOff2
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if false && repIndex >= 0 && load6432(src, repIndex) == load6432(src, s+repOff) {
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// Consider history as well.
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var seq seq
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lenght := 8 + e.matchlen(s+8+repOff2, repIndex+8, src)
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seq.matchLen = uint32(lenght - zstdMinMatch)
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// We might be able to match backwards.
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// Extend as long as we can.
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start := s + repOff2
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// We end the search early, so we don't risk 0 literals
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// and have to do special offset treatment.
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startLimit := nextEmit + 1
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tMin := s - e.maxMatchOff
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if tMin < 0 {
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tMin = 0
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}
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for repIndex > tMin && start > startLimit && src[repIndex-1] == src[start-1] && seq.matchLen < maxMatchLength-zstdMinMatch-1 {
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repIndex--
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start--
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seq.matchLen++
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}
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addLiterals(&seq, start)
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||||
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||||
// rep 2
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||||
seq.offset = 2
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if debugSequences {
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println("repeat sequence 2", seq, "next s:", s)
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||||
}
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||||
blk.sequences = append(blk.sequences, seq)
|
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|
||||
index0 := s + repOff2
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s += lenght + repOff2
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nextEmit = s
|
||||
if s >= sLimit {
|
||||
if debugEncoder {
|
||||
println("repeat ended", s, lenght)
|
||||
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||||
}
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break encodeLoop
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}
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||||
// Index skipped...
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||||
for index0 < s-1 {
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||||
cv0 := load6432(src, index0)
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||||
cv1 := cv0 >> 8
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h0 := hashLen(cv0, betterLongTableBits, betterLongLen)
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||||
off := index0 + e.cur
|
||||
e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
|
||||
e.markLongShardDirty(h0)
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||||
h1 := hashLen(cv1, betterShortTableBits, betterShortLen)
|
||||
e.table[h1] = tableEntry{offset: off + 1, val: uint32(cv1)}
|
||||
e.markShortShardDirty(h1)
|
||||
index0 += 2
|
||||
}
|
||||
cv = load6432(src, s)
|
||||
// Swap offsets
|
||||
offset1, offset2 = offset2, offset1
|
||||
continue
|
||||
}
|
||||
}
|
||||
// Find the offsets of our two matches.
|
||||
coffsetL := candidateL.offset - e.cur
|
||||
coffsetLP := candidateL.prev - e.cur
|
||||
|
||||
// Check if we have a long match.
|
||||
if s-coffsetL < e.maxMatchOff && cv == load6432(src, coffsetL) {
|
||||
// Found a long match, at least 8 bytes.
|
||||
matched = e.matchlen(s+8, coffsetL+8, src) + 8
|
||||
t = coffsetL
|
||||
if debugAsserts && s <= t {
|
||||
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
||||
}
|
||||
if debugAsserts && s-t > e.maxMatchOff {
|
||||
panic("s - t >e.maxMatchOff")
|
||||
}
|
||||
if debugMatches {
|
||||
println("long match")
|
||||
}
|
||||
|
||||
if s-coffsetLP < e.maxMatchOff && cv == load6432(src, coffsetLP) {
|
||||
// Found a long match, at least 8 bytes.
|
||||
prevMatch := e.matchlen(s+8, coffsetLP+8, src) + 8
|
||||
if prevMatch > matched {
|
||||
matched = prevMatch
|
||||
t = coffsetLP
|
||||
}
|
||||
if debugAsserts && s <= t {
|
||||
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
||||
}
|
||||
if debugAsserts && s-t > e.maxMatchOff {
|
||||
panic("s - t >e.maxMatchOff")
|
||||
}
|
||||
if debugMatches {
|
||||
println("long match")
|
||||
}
|
||||
}
|
||||
break
|
||||
}
|
||||
|
||||
// Check if we have a long match on prev.
|
||||
if s-coffsetLP < e.maxMatchOff && cv == load6432(src, coffsetLP) {
|
||||
// Found a long match, at least 8 bytes.
|
||||
matched = e.matchlen(s+8, coffsetLP+8, src) + 8
|
||||
t = coffsetLP
|
||||
if debugAsserts && s <= t {
|
||||
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
||||
}
|
||||
if debugAsserts && s-t > e.maxMatchOff {
|
||||
panic("s - t >e.maxMatchOff")
|
||||
}
|
||||
if debugMatches {
|
||||
println("long match")
|
||||
}
|
||||
break
|
||||
}
|
||||
|
||||
coffsetS := candidateS.offset - e.cur
|
||||
|
||||
// Check if we have a short match.
|
||||
if s-coffsetS < e.maxMatchOff && uint32(cv) == candidateS.val {
|
||||
// found a regular match
|
||||
matched = e.matchlen(s+4, coffsetS+4, src) + 4
|
||||
|
||||
// See if we can find a long match at s+1
|
||||
const checkAt = 1
|
||||
cv := load6432(src, s+checkAt)
|
||||
nextHashL = hashLen(cv, betterLongTableBits, betterLongLen)
|
||||
candidateL = e.longTable[nextHashL]
|
||||
coffsetL = candidateL.offset - e.cur
|
||||
|
||||
// We can store it, since we have at least a 4 byte match.
|
||||
e.longTable[nextHashL] = prevEntry{offset: s + checkAt + e.cur, prev: candidateL.offset}
|
||||
e.markLongShardDirty(nextHashL)
|
||||
if s-coffsetL < e.maxMatchOff && cv == load6432(src, coffsetL) {
|
||||
// Found a long match, at least 8 bytes.
|
||||
matchedNext := e.matchlen(s+8+checkAt, coffsetL+8, src) + 8
|
||||
if matchedNext > matched {
|
||||
t = coffsetL
|
||||
s += checkAt
|
||||
matched = matchedNext
|
||||
if debugMatches {
|
||||
println("long match (after short)")
|
||||
}
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
// Check prev long...
|
||||
coffsetL = candidateL.prev - e.cur
|
||||
if s-coffsetL < e.maxMatchOff && cv == load6432(src, coffsetL) {
|
||||
// Found a long match, at least 8 bytes.
|
||||
matchedNext := e.matchlen(s+8+checkAt, coffsetL+8, src) + 8
|
||||
if matchedNext > matched {
|
||||
t = coffsetL
|
||||
s += checkAt
|
||||
matched = matchedNext
|
||||
if debugMatches {
|
||||
println("prev long match (after short)")
|
||||
}
|
||||
break
|
||||
}
|
||||
}
|
||||
t = coffsetS
|
||||
if debugAsserts && s <= t {
|
||||
panic(fmt.Sprintf("s (%d) <= t (%d)", s, t))
|
||||
}
|
||||
if debugAsserts && s-t > e.maxMatchOff {
|
||||
panic("s - t >e.maxMatchOff")
|
||||
}
|
||||
if debugAsserts && t < 0 {
|
||||
panic("t<0")
|
||||
}
|
||||
if debugMatches {
|
||||
println("short match")
|
||||
}
|
||||
break
|
||||
}
|
||||
|
||||
// No match found, move forward in input.
|
||||
s += stepSize + ((s - nextEmit) >> (kSearchStrength - 1))
|
||||
if s >= sLimit {
|
||||
break encodeLoop
|
||||
}
|
||||
cv = load6432(src, s)
|
||||
}
|
||||
// Try to find a better match by searching for a long match at the end of the current best match
|
||||
if s+matched < sLimit {
|
||||
nextHashL := hashLen(load6432(src, s+matched), betterLongTableBits, betterLongLen)
|
||||
cv := load3232(src, s)
|
||||
candidateL := e.longTable[nextHashL]
|
||||
coffsetL := candidateL.offset - e.cur - matched
|
||||
if coffsetL >= 0 && coffsetL < s && s-coffsetL < e.maxMatchOff && cv == load3232(src, coffsetL) {
|
||||
// Found a long match, at least 4 bytes.
|
||||
matchedNext := e.matchlen(s+4, coffsetL+4, src) + 4
|
||||
if matchedNext > matched {
|
||||
t = coffsetL
|
||||
matched = matchedNext
|
||||
if debugMatches {
|
||||
println("long match at end-of-match")
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// Check prev long...
|
||||
if true {
|
||||
coffsetL = candidateL.prev - e.cur - matched
|
||||
if coffsetL >= 0 && coffsetL < s && s-coffsetL < e.maxMatchOff && cv == load3232(src, coffsetL) {
|
||||
// Found a long match, at least 4 bytes.
|
||||
matchedNext := e.matchlen(s+4, coffsetL+4, src) + 4
|
||||
if matchedNext > matched {
|
||||
t = coffsetL
|
||||
matched = matchedNext
|
||||
if debugMatches {
|
||||
println("prev long match at end-of-match")
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
// A match has been found. Update recent offsets.
|
||||
offset2 = offset1
|
||||
offset1 = s - t
|
||||
|
||||
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 := matched
|
||||
|
||||
// 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
|
||||
for index0 < s-1 {
|
||||
cv0 := load6432(src, index0)
|
||||
cv1 := cv0 >> 8
|
||||
h0 := hashLen(cv0, betterLongTableBits, betterLongLen)
|
||||
off := index0 + e.cur
|
||||
e.longTable[h0] = prevEntry{offset: off, prev: e.longTable[h0].offset}
|
||||
e.markLongShardDirty(h0)
|
||||
h1 := hashLen(cv1, betterShortTableBits, betterShortLen)
|
||||
e.table[h1] = tableEntry{offset: off + 1, val: uint32(cv1)}
|
||||
e.markShortShardDirty(h1)
|
||||
index0 += 2
|
||||
}
|
||||
|
||||
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.
|
||||
nextHashL := hashLen(cv, betterLongTableBits, betterLongLen)
|
||||
nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
|
||||
|
||||
// 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.markLongShardDirty(nextHashL)
|
||||
e.table[nextHashS] = tableEntry{offset: s + e.cur, val: uint32(cv)}
|
||||
e.markShortShardDirty(nextHashS)
|
||||
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)
|
||||
if debugEncoder {
|
||||
println("returning, recent offsets:", blk.recentOffsets, "extra literals:", blk.extraLits)
|
||||
}
|
||||
}
|
||||
|
||||
// ResetDict will reset and set a dictionary if not nil
|
||||
func (e *betterFastEncoder) Reset(d *dict, singleBlock bool) {
|
||||
e.resetBase(d, singleBlock)
|
||||
if d != nil {
|
||||
panic("betterFastEncoder: Reset with dict")
|
||||
}
|
||||
}
|
||||
|
||||
// ResetDict will reset and set a dictionary if not nil
|
||||
func (e *betterFastEncoderDict) Reset(d *dict, singleBlock bool) {
|
||||
e.resetBase(d, singleBlock)
|
||||
if d == nil {
|
||||
return
|
||||
@@ -535,10 +1124,10 @@ func (e *betterFastEncoder) Reset(d *dict, singleBlock bool) {
|
||||
const hashLog = betterShortTableBits
|
||||
|
||||
cv := load6432(d.content, i-e.maxMatchOff)
|
||||
nextHash := hash5(cv, hashLog) // 0 -> 4
|
||||
nextHash1 := hash5(cv>>8, hashLog) // 1 -> 5
|
||||
nextHash2 := hash5(cv>>16, hashLog) // 2 -> 6
|
||||
nextHash3 := hash5(cv>>24, hashLog) // 3 -> 7
|
||||
nextHash := hashLen(cv, hashLog, betterShortLen) // 0 -> 4
|
||||
nextHash1 := hashLen(cv>>8, hashLog, betterShortLen) // 1 -> 5
|
||||
nextHash2 := hashLen(cv>>16, hashLog, betterShortLen) // 2 -> 6
|
||||
nextHash3 := hashLen(cv>>24, hashLog, betterShortLen) // 3 -> 7
|
||||
e.dictTable[nextHash] = tableEntry{
|
||||
val: uint32(cv),
|
||||
offset: i,
|
||||
@@ -557,6 +1146,7 @@ func (e *betterFastEncoder) Reset(d *dict, singleBlock bool) {
|
||||
}
|
||||
}
|
||||
e.lastDictID = d.id
|
||||
e.allDirty = true
|
||||
}
|
||||
|
||||
// Init or copy dict table
|
||||
@@ -566,7 +1156,7 @@ func (e *betterFastEncoder) Reset(d *dict, singleBlock bool) {
|
||||
}
|
||||
if len(d.content) >= 8 {
|
||||
cv := load6432(d.content, 0)
|
||||
h := hash8(cv, betterLongTableBits)
|
||||
h := hashLen(cv, betterLongTableBits, betterLongLen)
|
||||
e.dictLongTable[h] = prevEntry{
|
||||
offset: e.maxMatchOff,
|
||||
prev: e.dictLongTable[h].offset,
|
||||
@@ -576,7 +1166,7 @@ func (e *betterFastEncoder) Reset(d *dict, singleBlock bool) {
|
||||
off := 8 // First to read
|
||||
for i := e.maxMatchOff + 1; i < end; i++ {
|
||||
cv = cv>>8 | (uint64(d.content[off]) << 56)
|
||||
h := hash8(cv, betterLongTableBits)
|
||||
h := hashLen(cv, betterLongTableBits, betterLongLen)
|
||||
e.dictLongTable[h] = prevEntry{
|
||||
offset: i,
|
||||
prev: e.dictLongTable[h].offset,
|
||||
@@ -585,11 +1175,72 @@ func (e *betterFastEncoder) Reset(d *dict, singleBlock bool) {
|
||||
}
|
||||
}
|
||||
e.lastDictID = d.id
|
||||
e.allDirty = true
|
||||
}
|
||||
// Reset table to initial state
|
||||
copy(e.longTable[:], e.dictLongTable)
|
||||
|
||||
e.cur = e.maxMatchOff
|
||||
// Reset table to initial state
|
||||
copy(e.table[:], e.dictTable)
|
||||
{
|
||||
dirtyShardCnt := 0
|
||||
if !e.allDirty {
|
||||
for i := range e.shortTableShardDirty {
|
||||
if e.shortTableShardDirty[i] {
|
||||
dirtyShardCnt++
|
||||
}
|
||||
}
|
||||
}
|
||||
const shardCnt = betterShortTableShardCnt
|
||||
const shardSize = betterShortTableShardSize
|
||||
if e.allDirty || dirtyShardCnt > shardCnt*4/6 {
|
||||
copy(e.table[:], e.dictTable)
|
||||
for i := range e.shortTableShardDirty {
|
||||
e.shortTableShardDirty[i] = false
|
||||
}
|
||||
} else {
|
||||
for i := range e.shortTableShardDirty {
|
||||
if !e.shortTableShardDirty[i] {
|
||||
continue
|
||||
}
|
||||
|
||||
copy(e.table[i*shardSize:(i+1)*shardSize], e.dictTable[i*shardSize:(i+1)*shardSize])
|
||||
e.shortTableShardDirty[i] = false
|
||||
}
|
||||
}
|
||||
}
|
||||
{
|
||||
dirtyShardCnt := 0
|
||||
if !e.allDirty {
|
||||
for i := range e.shortTableShardDirty {
|
||||
if e.shortTableShardDirty[i] {
|
||||
dirtyShardCnt++
|
||||
}
|
||||
}
|
||||
}
|
||||
const shardCnt = betterLongTableShardCnt
|
||||
const shardSize = betterLongTableShardSize
|
||||
if e.allDirty || dirtyShardCnt > shardCnt*4/6 {
|
||||
copy(e.longTable[:], e.dictLongTable)
|
||||
for i := range e.longTableShardDirty {
|
||||
e.longTableShardDirty[i] = false
|
||||
}
|
||||
} else {
|
||||
for i := range e.longTableShardDirty {
|
||||
if !e.longTableShardDirty[i] {
|
||||
continue
|
||||
}
|
||||
|
||||
copy(e.longTable[i*shardSize:(i+1)*shardSize], e.dictLongTable[i*shardSize:(i+1)*shardSize])
|
||||
e.longTableShardDirty[i] = false
|
||||
}
|
||||
}
|
||||
}
|
||||
e.cur = e.maxMatchOff
|
||||
e.allDirty = false
|
||||
}
|
||||
|
||||
func (e *betterFastEncoderDict) markLongShardDirty(entryNum uint32) {
|
||||
e.longTableShardDirty[entryNum/betterLongTableShardSize] = true
|
||||
}
|
||||
|
||||
func (e *betterFastEncoderDict) markShortShardDirty(entryNum uint32) {
|
||||
e.shortTableShardDirty[entryNum/betterShortTableShardSize] = true
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user