mirror of
https://github.com/optim-enterprises-bv/vault.git
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Update vendoring
This commit is contained in:
16
vendor/github.com/golang/snappy/.gitignore
generated
vendored
16
vendor/github.com/golang/snappy/.gitignore
generated
vendored
@@ -1,16 +0,0 @@
|
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cmd/snappytool/snappytool
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testdata/bench
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||||
|
||||
# These explicitly listed benchmark data files are for an obsolete version of
|
||||
# snappy_test.go.
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||||
testdata/alice29.txt
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||||
testdata/asyoulik.txt
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||||
testdata/fireworks.jpeg
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||||
testdata/geo.protodata
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||||
testdata/html
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||||
testdata/html_x_4
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||||
testdata/kppkn.gtb
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||||
testdata/lcet10.txt
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||||
testdata/paper-100k.pdf
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||||
testdata/plrabn12.txt
|
||||
testdata/urls.10K
|
||||
94
vendor/github.com/golang/snappy/README
generated
vendored
94
vendor/github.com/golang/snappy/README
generated
vendored
@@ -13,65 +13,65 @@ Benchmarks.
|
||||
The golang/snappy benchmarks include compressing (Z) and decompressing (U) ten
|
||||
or so files, the same set used by the C++ Snappy code (github.com/google/snappy
|
||||
and note the "google", not "golang"). On an "Intel(R) Core(TM) i7-3770 CPU @
|
||||
3.40GHz", Go's GOARCH=amd64 numbers as of 2016-04-29:
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||||
3.40GHz", Go's GOARCH=amd64 numbers as of 2016-05-29:
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||||
|
||||
"go test -test.bench=."
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||||
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||||
_UFlat0-8 2.23GB/s ± 1% html
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||||
_UFlat1-8 1.43GB/s ± 0% urls
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||||
_UFlat2-8 23.7GB/s ± 1% jpg
|
||||
_UFlat3-8 1.93GB/s ± 0% jpg_200
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||||
_UFlat4-8 13.9GB/s ± 2% pdf
|
||||
_UFlat5-8 2.00GB/s ± 0% html4
|
||||
_UFlat6-8 829MB/s ± 0% txt1
|
||||
_UFlat7-8 799MB/s ± 0% txt2
|
||||
_UFlat8-8 871MB/s ± 0% txt3
|
||||
_UFlat9-8 730MB/s ± 0% txt4
|
||||
_UFlat10-8 2.87GB/s ± 0% pb
|
||||
_UFlat11-8 1.07GB/s ± 0% gaviota
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||||
_UFlat0-8 2.19GB/s ± 0% html
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||||
_UFlat1-8 1.41GB/s ± 0% urls
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||||
_UFlat2-8 23.5GB/s ± 2% jpg
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||||
_UFlat3-8 1.91GB/s ± 0% jpg_200
|
||||
_UFlat4-8 14.0GB/s ± 1% pdf
|
||||
_UFlat5-8 1.97GB/s ± 0% html4
|
||||
_UFlat6-8 814MB/s ± 0% txt1
|
||||
_UFlat7-8 785MB/s ± 0% txt2
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||||
_UFlat8-8 857MB/s ± 0% txt3
|
||||
_UFlat9-8 719MB/s ± 1% txt4
|
||||
_UFlat10-8 2.84GB/s ± 0% pb
|
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_UFlat11-8 1.05GB/s ± 0% gaviota
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||||
|
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_ZFlat0-8 1.04GB/s ± 0% html
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||||
_ZFlat1-8 536MB/s ± 0% urls
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_ZFlat2-8 16.3GB/s ± 2% jpg
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_ZFlat3-8 762MB/s ± 0% jpg_200
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_ZFlat4-8 9.48GB/s ± 1% pdf
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_ZFlat5-8 990MB/s ± 0% html4
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_ZFlat6-8 381MB/s ± 0% txt1
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_ZFlat7-8 353MB/s ± 0% txt2
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_ZFlat8-8 398MB/s ± 0% txt3
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_ZFlat9-8 329MB/s ± 0% txt4
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||||
_ZFlat10-8 1.35GB/s ± 1% pb
|
||||
_ZFlat11-8 608MB/s ± 0% gaviota
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||||
_ZFlat1-8 534MB/s ± 0% urls
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||||
_ZFlat2-8 15.7GB/s ± 1% jpg
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||||
_ZFlat3-8 740MB/s ± 3% jpg_200
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_ZFlat4-8 9.20GB/s ± 1% pdf
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||||
_ZFlat5-8 991MB/s ± 0% html4
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_ZFlat6-8 379MB/s ± 0% txt1
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_ZFlat7-8 352MB/s ± 0% txt2
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_ZFlat8-8 396MB/s ± 1% txt3
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||||
_ZFlat9-8 327MB/s ± 1% txt4
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_ZFlat10-8 1.33GB/s ± 1% pb
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_ZFlat11-8 605MB/s ± 1% gaviota
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|
||||
|
||||
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"go test -test.bench=. -tags=noasm"
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_UFlat0-8 637MB/s ± 0% html
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_UFlat1-8 506MB/s ± 0% urls
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_UFlat2-8 23.0GB/s ± 5% jpg
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_UFlat3-8 1.17GB/s ± 0% jpg_200
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_UFlat4-8 4.44GB/s ± 1% pdf
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||||
_UFlat5-8 623MB/s ± 0% html4
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||||
_UFlat6-8 300MB/s ± 1% txt1
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_UFlat7-8 293MB/s ± 0% txt2
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||||
_UFlat8-8 316MB/s ± 0% txt3
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||||
_UFlat9-8 285MB/s ± 0% txt4
|
||||
_UFlat10-8 768MB/s ± 0% pb
|
||||
_UFlat11-8 406MB/s ± 1% gaviota
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||||
_UFlat0-8 621MB/s ± 2% html
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||||
_UFlat1-8 494MB/s ± 1% urls
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||||
_UFlat2-8 23.2GB/s ± 1% jpg
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||||
_UFlat3-8 1.12GB/s ± 1% jpg_200
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||||
_UFlat4-8 4.35GB/s ± 1% pdf
|
||||
_UFlat5-8 609MB/s ± 0% html4
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||||
_UFlat6-8 296MB/s ± 0% txt1
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||||
_UFlat7-8 288MB/s ± 0% txt2
|
||||
_UFlat8-8 309MB/s ± 1% txt3
|
||||
_UFlat9-8 280MB/s ± 1% txt4
|
||||
_UFlat10-8 753MB/s ± 0% pb
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_UFlat11-8 400MB/s ± 0% gaviota
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||||
|
||||
_ZFlat0-8 411MB/s ± 1% html
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||||
_ZFlat0-8 409MB/s ± 1% html
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||||
_ZFlat1-8 250MB/s ± 1% urls
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||||
_ZFlat2-8 12.7GB/s ± 1% jpg
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_ZFlat3-8 157MB/s ± 0% jpg_200
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_ZFlat4-8 2.95GB/s ± 0% pdf
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||||
_ZFlat5-8 406MB/s ± 0% html4
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||||
_ZFlat6-8 182MB/s ± 0% txt1
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||||
_ZFlat7-8 173MB/s ± 1% txt2
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||||
_ZFlat8-8 191MB/s ± 0% txt3
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||||
_ZFlat9-8 166MB/s ± 0% txt4
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||||
_ZFlat10-8 480MB/s ± 0% pb
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_ZFlat11-8 272MB/s ± 0% gaviota
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_ZFlat2-8 12.3GB/s ± 1% jpg
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_ZFlat3-8 132MB/s ± 0% jpg_200
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_ZFlat4-8 2.92GB/s ± 0% pdf
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||||
_ZFlat5-8 405MB/s ± 1% html4
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||||
_ZFlat6-8 179MB/s ± 1% txt1
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_ZFlat7-8 170MB/s ± 1% txt2
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||||
_ZFlat8-8 189MB/s ± 1% txt3
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||||
_ZFlat9-8 164MB/s ± 1% txt4
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||||
_ZFlat10-8 479MB/s ± 1% pb
|
||||
_ZFlat11-8 270MB/s ± 1% gaviota
|
||||
|
||||
|
||||
|
||||
|
||||
4
vendor/github.com/golang/snappy/decode.go
generated
vendored
4
vendor/github.com/golang/snappy/decode.go
generated
vendored
@@ -18,7 +18,6 @@ var (
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||||
// ErrUnsupported reports that the input isn't supported.
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||||
ErrUnsupported = errors.New("snappy: unsupported input")
|
||||
|
||||
errUnsupportedCopy4Tag = errors.New("snappy: unsupported COPY_4 tag")
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||||
errUnsupportedLiteralLength = errors.New("snappy: unsupported literal length")
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||||
)
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||||
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||||
@@ -46,7 +45,6 @@ func decodedLen(src []byte) (blockLen, headerLen int, err error) {
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||||
const (
|
||||
decodeErrCodeCorrupt = 1
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||||
decodeErrCodeUnsupportedLiteralLength = 2
|
||||
decodeErrCodeUnsupportedCopy4Tag = 3
|
||||
)
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||||
|
||||
// Decode returns the decoded form of src. The returned slice may be a sub-
|
||||
@@ -69,8 +67,6 @@ func Decode(dst, src []byte) ([]byte, error) {
|
||||
return dst, nil
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||||
case decodeErrCodeUnsupportedLiteralLength:
|
||||
return nil, errUnsupportedLiteralLength
|
||||
case decodeErrCodeUnsupportedCopy4Tag:
|
||||
return nil, errUnsupportedCopy4Tag
|
||||
}
|
||||
return nil, ErrCorrupt
|
||||
}
|
||||
|
||||
30
vendor/github.com/golang/snappy/decode_amd64.s
generated
vendored
30
vendor/github.com/golang/snappy/decode_amd64.s
generated
vendored
@@ -226,6 +226,25 @@ tagLit63:
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||||
// ----------------------------------------
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||||
// The code below handles copy tags.
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||||
|
||||
tagCopy4:
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||||
// case tagCopy4:
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||||
// s += 5
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||||
ADDQ $5, SI
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|
||||
// if uint(s) > uint(len(src)) { etc }
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||||
MOVQ SI, BX
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SUBQ R11, BX
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||||
CMPQ BX, R12
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||||
JA errCorrupt
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// length = 1 + int(src[s-5])>>2
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SHRQ $2, CX
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INCQ CX
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// offset = int(uint32(src[s-4]) | uint32(src[s-3])<<8 | uint32(src[s-2])<<16 | uint32(src[s-1])<<24)
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MOVLQZX -4(SI), DX
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JMP doCopy
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tagCopy2:
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// case tagCopy2:
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// s += 3
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@@ -241,7 +260,7 @@ tagCopy2:
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SHRQ $2, CX
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INCQ CX
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// offset = int(src[s-2]) | int(src[s-1])<<8
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// offset = int(uint32(src[s-2]) | uint32(src[s-1])<<8)
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MOVWQZX -2(SI), DX
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JMP doCopy
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@@ -251,7 +270,7 @@ tagCopy:
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// - CX == src[s]
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CMPQ BX, $2
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JEQ tagCopy2
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JA errUC4T
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JA tagCopy4
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// case tagCopy1:
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// s += 2
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@@ -263,7 +282,7 @@ tagCopy:
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CMPQ BX, R12
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JA errCorrupt
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// offset = int(src[s-2])&0xe0<<3 | int(src[s-1])
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// offset = int(uint32(src[s-2])&0xe0<<3 | uint32(src[s-1]))
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||||
MOVQ CX, DX
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||||
ANDQ $0xe0, DX
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SHLQ $3, DX
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||||
@@ -469,8 +488,3 @@ errCorrupt:
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||||
// return decodeErrCodeCorrupt
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MOVQ $1, ret+48(FP)
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||||
RET
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||||
|
||||
errUC4T:
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||||
// return decodeErrCodeUnsupportedCopy4Tag
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||||
MOVQ $3, ret+48(FP)
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||||
RET
|
||||
|
||||
96
vendor/github.com/golang/snappy/decode_other.go
generated
vendored
96
vendor/github.com/golang/snappy/decode_other.go
generated
vendored
@@ -1,96 +0,0 @@
|
||||
// Copyright 2016 The Snappy-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.
|
||||
|
||||
// +build !amd64 appengine !gc noasm
|
||||
|
||||
package snappy
|
||||
|
||||
// decode writes the decoding of src to dst. It assumes that the varint-encoded
|
||||
// length of the decompressed bytes has already been read, and that len(dst)
|
||||
// equals that length.
|
||||
//
|
||||
// It returns 0 on success or a decodeErrCodeXxx error code on failure.
|
||||
func decode(dst, src []byte) int {
|
||||
var d, s, offset, length int
|
||||
for s < len(src) {
|
||||
switch src[s] & 0x03 {
|
||||
case tagLiteral:
|
||||
x := uint32(src[s] >> 2)
|
||||
switch {
|
||||
case x < 60:
|
||||
s++
|
||||
case x == 60:
|
||||
s += 2
|
||||
if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
x = uint32(src[s-1])
|
||||
case x == 61:
|
||||
s += 3
|
||||
if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
x = uint32(src[s-2]) | uint32(src[s-1])<<8
|
||||
case x == 62:
|
||||
s += 4
|
||||
if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
x = uint32(src[s-3]) | uint32(src[s-2])<<8 | uint32(src[s-1])<<16
|
||||
case x == 63:
|
||||
s += 5
|
||||
if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
x = uint32(src[s-4]) | uint32(src[s-3])<<8 | uint32(src[s-2])<<16 | uint32(src[s-1])<<24
|
||||
}
|
||||
length = int(x) + 1
|
||||
if length <= 0 {
|
||||
return decodeErrCodeUnsupportedLiteralLength
|
||||
}
|
||||
if length > len(dst)-d || length > len(src)-s {
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
copy(dst[d:], src[s:s+length])
|
||||
d += length
|
||||
s += length
|
||||
continue
|
||||
|
||||
case tagCopy1:
|
||||
s += 2
|
||||
if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
length = 4 + int(src[s-2])>>2&0x7
|
||||
offset = int(src[s-2])&0xe0<<3 | int(src[s-1])
|
||||
|
||||
case tagCopy2:
|
||||
s += 3
|
||||
if uint(s) > uint(len(src)) { // The uint conversions catch overflow from the previous line.
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
length = 1 + int(src[s-3])>>2
|
||||
offset = int(src[s-2]) | int(src[s-1])<<8
|
||||
|
||||
case tagCopy4:
|
||||
return decodeErrCodeUnsupportedCopy4Tag
|
||||
}
|
||||
|
||||
if offset <= 0 || d < offset || length > len(dst)-d {
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
// Copy from an earlier sub-slice of dst to a later sub-slice. Unlike
|
||||
// the built-in copy function, this byte-by-byte copy always runs
|
||||
// forwards, even if the slices overlap. Conceptually, this is:
|
||||
//
|
||||
// d += forwardCopy(dst[d:d+length], dst[d-offset:])
|
||||
for end := d + length; d != end; d++ {
|
||||
dst[d] = dst[d-offset]
|
||||
}
|
||||
}
|
||||
if d != len(dst) {
|
||||
return decodeErrCodeCorrupt
|
||||
}
|
||||
return 0
|
||||
}
|
||||
2
vendor/github.com/golang/snappy/encode_amd64.go
generated
vendored
2
vendor/github.com/golang/snappy/encode_amd64.go
generated
vendored
@@ -26,4 +26,4 @@ func extendMatch(src []byte, i, j int) int
|
||||
// encodeBlock has the same semantics as in encode_other.go.
|
||||
//
|
||||
//go:noescape
|
||||
func encodeBlock(dst, src []byte) (d int)
|
||||
func encodeBlock(dst, src []byte) (d int)
|
||||
238
vendor/github.com/golang/snappy/encode_other.go
generated
vendored
238
vendor/github.com/golang/snappy/encode_other.go
generated
vendored
@@ -1,238 +0,0 @@
|
||||
// Copyright 2016 The Snappy-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.
|
||||
|
||||
// +build !amd64 appengine !gc noasm
|
||||
|
||||
package snappy
|
||||
|
||||
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
|
||||
}
|
||||
|
||||
// emitLiteral writes a literal chunk and returns the number of bytes written.
|
||||
//
|
||||
// It assumes that:
|
||||
// dst is long enough to hold the encoded bytes
|
||||
// 1 <= len(lit) && len(lit) <= 65536
|
||||
func emitLiteral(dst, lit []byte) int {
|
||||
i, n := 0, uint(len(lit)-1)
|
||||
switch {
|
||||
case n < 60:
|
||||
dst[0] = uint8(n)<<2 | tagLiteral
|
||||
i = 1
|
||||
case n < 1<<8:
|
||||
dst[0] = 60<<2 | tagLiteral
|
||||
dst[1] = uint8(n)
|
||||
i = 2
|
||||
default:
|
||||
dst[0] = 61<<2 | tagLiteral
|
||||
dst[1] = uint8(n)
|
||||
dst[2] = uint8(n >> 8)
|
||||
i = 3
|
||||
}
|
||||
return i + copy(dst[i:], lit)
|
||||
}
|
||||
|
||||
// emitCopy writes a copy chunk and returns the number of bytes written.
|
||||
//
|
||||
// It assumes that:
|
||||
// dst is long enough to hold the encoded bytes
|
||||
// 1 <= offset && offset <= 65535
|
||||
// 4 <= length && length <= 65535
|
||||
func emitCopy(dst []byte, offset, length int) int {
|
||||
i := 0
|
||||
// The maximum length for a single tagCopy1 or tagCopy2 op is 64 bytes. The
|
||||
// threshold for this loop is a little higher (at 68 = 64 + 4), and the
|
||||
// length emitted down below is is a little lower (at 60 = 64 - 4), because
|
||||
// it's shorter to encode a length 67 copy as a length 60 tagCopy2 followed
|
||||
// by a length 7 tagCopy1 (which encodes as 3+2 bytes) than to encode it as
|
||||
// a length 64 tagCopy2 followed by a length 3 tagCopy2 (which encodes as
|
||||
// 3+3 bytes). The magic 4 in the 64±4 is because the minimum length for a
|
||||
// tagCopy1 op is 4 bytes, which is why a length 3 copy has to be an
|
||||
// encodes-as-3-bytes tagCopy2 instead of an encodes-as-2-bytes tagCopy1.
|
||||
for length >= 68 {
|
||||
// Emit a length 64 copy, encoded as 3 bytes.
|
||||
dst[i+0] = 63<<2 | tagCopy2
|
||||
dst[i+1] = uint8(offset)
|
||||
dst[i+2] = uint8(offset >> 8)
|
||||
i += 3
|
||||
length -= 64
|
||||
}
|
||||
if length > 64 {
|
||||
// Emit a length 60 copy, encoded as 3 bytes.
|
||||
dst[i+0] = 59<<2 | tagCopy2
|
||||
dst[i+1] = uint8(offset)
|
||||
dst[i+2] = uint8(offset >> 8)
|
||||
i += 3
|
||||
length -= 60
|
||||
}
|
||||
if length >= 12 || offset >= 2048 {
|
||||
// Emit the remaining copy, encoded as 3 bytes.
|
||||
dst[i+0] = uint8(length-1)<<2 | tagCopy2
|
||||
dst[i+1] = uint8(offset)
|
||||
dst[i+2] = uint8(offset >> 8)
|
||||
return i + 3
|
||||
}
|
||||
// Emit the remaining copy, encoded as 2 bytes.
|
||||
dst[i+0] = uint8(offset>>8)<<5 | uint8(length-4)<<2 | tagCopy1
|
||||
dst[i+1] = uint8(offset)
|
||||
return i + 2
|
||||
}
|
||||
|
||||
// extendMatch returns the largest k such that k <= len(src) and that
|
||||
// src[i:i+k-j] and src[j:k] have the same contents.
|
||||
//
|
||||
// It assumes that:
|
||||
// 0 <= i && i < j && j <= len(src)
|
||||
func extendMatch(src []byte, i, j int) int {
|
||||
for ; j < len(src) && src[i] == src[j]; i, j = i+1, j+1 {
|
||||
}
|
||||
return j
|
||||
}
|
||||
|
||||
func hash(u, shift uint32) uint32 {
|
||||
return (u * 0x1e35a7bd) >> shift
|
||||
}
|
||||
|
||||
// encodeBlock encodes a non-empty src to a guaranteed-large-enough dst. It
|
||||
// assumes that the varint-encoded length of the decompressed bytes has already
|
||||
// been written.
|
||||
//
|
||||
// It also assumes that:
|
||||
// len(dst) >= MaxEncodedLen(len(src)) &&
|
||||
// minNonLiteralBlockSize <= len(src) && len(src) <= maxBlockSize
|
||||
func encodeBlock(dst, src []byte) (d int) {
|
||||
// Initialize the hash table. Its size ranges from 1<<8 to 1<<14 inclusive.
|
||||
// The table element type is uint16, as s < sLimit and sLimit < len(src)
|
||||
// and len(src) <= maxBlockSize and maxBlockSize == 65536.
|
||||
const (
|
||||
maxTableSize = 1 << 14
|
||||
// tableMask is redundant, but helps the compiler eliminate bounds
|
||||
// checks.
|
||||
tableMask = maxTableSize - 1
|
||||
)
|
||||
shift := uint32(32 - 8)
|
||||
for tableSize := 1 << 8; tableSize < maxTableSize && tableSize < len(src); tableSize *= 2 {
|
||||
shift--
|
||||
}
|
||||
// In Go, all array elements are zero-initialized, so there is no advantage
|
||||
// to a smaller tableSize per se. However, it matches the C++ algorithm,
|
||||
// and in the asm versions of this code, we can get away with zeroing only
|
||||
// the first tableSize elements.
|
||||
var table [maxTableSize]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), shift)
|
||||
|
||||
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), shift)
|
||||
if 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.
|
||||
d += emitLiteral(dst[d:], 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:
|
||||
// s = extendMatch(src, candidate+4, s+4)
|
||||
s += 4
|
||||
for i := candidate + 4; s < len(src) && src[i] == src[s]; i, s = i+1, s+1 {
|
||||
}
|
||||
|
||||
d += emitCopy(dst[d:], base-candidate, s-base)
|
||||
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), shift)
|
||||
table[prevHash&tableMask] = uint16(s - 1)
|
||||
currHash := hash(uint32(x>>8), shift)
|
||||
candidate = int(table[currHash&tableMask])
|
||||
table[currHash&tableMask] = uint16(s)
|
||||
if uint32(x>>8) != load32(src, candidate) {
|
||||
nextHash = hash(uint32(x>>16), shift)
|
||||
s++
|
||||
break
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
emitRemainder:
|
||||
if nextEmit < len(src) {
|
||||
d += emitLiteral(dst[d:], src[nextEmit:])
|
||||
}
|
||||
return d
|
||||
}
|
||||
7
vendor/github.com/golang/snappy/snappy.go
generated
vendored
7
vendor/github.com/golang/snappy/snappy.go
generated
vendored
@@ -6,7 +6,7 @@
|
||||
// It aims for very high speeds and reasonable compression.
|
||||
//
|
||||
// The C++ snappy implementation is at https://github.com/google/snappy
|
||||
package snappy
|
||||
package snappy // import "github.com/golang/snappy"
|
||||
|
||||
import (
|
||||
"hash/crc32"
|
||||
@@ -32,7 +32,10 @@ Lempel-Ziv compression algorithms. In particular:
|
||||
- For l == 2, the offset ranges in [0, 1<<16) and the length in [1, 65).
|
||||
The length is 1 + m. The offset is the little-endian unsigned integer
|
||||
denoted by the next 2 bytes.
|
||||
- For l == 3, this tag is a legacy format that is no longer supported.
|
||||
- For l == 3, this tag is a legacy format that is no longer issued by most
|
||||
encoders. Nonetheless, the offset ranges in [0, 1<<32) and the length in
|
||||
[1, 65). The length is 1 + m. The offset is the little-endian unsigned
|
||||
integer denoted by the next 4 bytes.
|
||||
*/
|
||||
const (
|
||||
tagLiteral = 0x00
|
||||
|
||||
Reference in New Issue
Block a user