Sebastiaan van Stijn 2022-08-26 01:46:28 +02:00
parent 1808c67d53
commit f7277806c8
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GPG Key ID: 76698F39D527CE8C
47 changed files with 6415 additions and 2306 deletions

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@ -47,7 +47,7 @@ require (
github.com/hashicorp/serf v0.8.5
github.com/imdario/mergo v0.3.12
github.com/ishidawataru/sctp v0.0.0-20210707070123-9a39160e9062
github.com/klauspost/compress v1.15.1
github.com/klauspost/compress v1.15.9
github.com/miekg/dns v1.1.27
github.com/mistifyio/go-zfs v2.1.2-0.20190413222219-f784269be439+incompatible
github.com/moby/buildkit v0.10.4

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@ -691,8 +691,9 @@ github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI
github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
github.com/klauspost/compress v1.11.3/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
github.com/klauspost/compress v1.11.13/go.mod h1:aoV0uJVorq1K+umq18yTdKaF57EivdYsUV+/s2qKfXs=
github.com/klauspost/compress v1.15.1 h1:y9FcTHGyrebwfP0ZZqFiaxTaiDnUrGkJkI+f583BL1A=
github.com/klauspost/compress v1.15.1/go.mod h1:/3/Vjq9QcHkK5uEr5lBEmyoZ1iFhe47etQ6QUkpK6sk=
github.com/klauspost/compress v1.15.9 h1:wKRjX6JRtDdrE9qwa4b/Cip7ACOshUI4smpCQanqjSY=
github.com/klauspost/compress v1.15.9/go.mod h1:PhcZ0MbTNciWF3rruxRgKxI5NkcHHrHUDtV4Yw2GlzU=
github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
github.com/konsorten/go-windows-terminal-sequences v1.0.2/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=

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@ -23,3 +23,10 @@ _testmain.go
*.test
*.prof
/s2/cmd/_s2sx/sfx-exe
# Linux perf files
perf.data
perf.data.old
# gdb history
.gdb_history

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@ -17,6 +17,72 @@ This package provides various compression algorithms.
# changelog
* July 13, 2022 (v1.15.8)
* gzip: fix stack exhaustion bug in Reader.Read https://github.com/klauspost/compress/pull/641
* s2: Add Index header trim/restore https://github.com/klauspost/compress/pull/638
* zstd: Optimize seqdeq amd64 asm by @greatroar in https://github.com/klauspost/compress/pull/636
* zstd: Improve decoder memcopy https://github.com/klauspost/compress/pull/637
* huff0: Pass a single bitReader pointer to asm by @greatroar in https://github.com/klauspost/compress/pull/634
* zstd: Branchless getBits for amd64 w/o BMI2 by @greatroar in https://github.com/klauspost/compress/pull/640
* gzhttp: Remove header before writing https://github.com/klauspost/compress/pull/639
* June 29, 2022 (v1.15.7)
* s2: Fix absolute forward seeks https://github.com/klauspost/compress/pull/633
* zip: Merge upstream https://github.com/klauspost/compress/pull/631
* zip: Re-add zip64 fix https://github.com/klauspost/compress/pull/624
* zstd: translate fseDecoder.buildDtable into asm by @WojciechMula in https://github.com/klauspost/compress/pull/598
* flate: Faster histograms https://github.com/klauspost/compress/pull/620
* deflate: Use compound hcode https://github.com/klauspost/compress/pull/622
* June 3, 2022 (v1.15.6)
* s2: Improve coding for long, close matches https://github.com/klauspost/compress/pull/613
* s2c: Add Snappy/S2 stream recompression https://github.com/klauspost/compress/pull/611
* zstd: Always use configured block size https://github.com/klauspost/compress/pull/605
* zstd: Fix incorrect hash table placement for dict encoding in default https://github.com/klauspost/compress/pull/606
* zstd: Apply default config to ZipDecompressor without options https://github.com/klauspost/compress/pull/608
* gzhttp: Exclude more common archive formats https://github.com/klauspost/compress/pull/612
* s2: Add ReaderIgnoreCRC https://github.com/klauspost/compress/pull/609
* s2: Remove sanity load on index creation https://github.com/klauspost/compress/pull/607
* snappy: Use dedicated function for scoring https://github.com/klauspost/compress/pull/614
* s2c+s2d: Use official snappy framed extension https://github.com/klauspost/compress/pull/610
* May 25, 2022 (v1.15.5)
* s2: Add concurrent stream decompression https://github.com/klauspost/compress/pull/602
* s2: Fix final emit oob read crash on amd64 https://github.com/klauspost/compress/pull/601
* huff0: asm implementation of Decompress1X by @WojciechMula https://github.com/klauspost/compress/pull/596
* zstd: Use 1 less goroutine for stream decoding https://github.com/klauspost/compress/pull/588
* zstd: Copy literal in 16 byte blocks when possible https://github.com/klauspost/compress/pull/592
* zstd: Speed up when WithDecoderLowmem(false) https://github.com/klauspost/compress/pull/599
* zstd: faster next state update in BMI2 version of decode by @WojciechMula in https://github.com/klauspost/compress/pull/593
* huff0: Do not check max size when reading table. https://github.com/klauspost/compress/pull/586
* flate: Inplace hashing for level 7-9 by @klauspost in https://github.com/klauspost/compress/pull/590
* May 11, 2022 (v1.15.4)
* huff0: decompress directly into output by @WojciechMula in [#577](https://github.com/klauspost/compress/pull/577)
* inflate: Keep dict on stack [#581](https://github.com/klauspost/compress/pull/581)
* zstd: Faster decoding memcopy in asm [#583](https://github.com/klauspost/compress/pull/583)
* zstd: Fix ignored crc [#580](https://github.com/klauspost/compress/pull/580)
* May 5, 2022 (v1.15.3)
* zstd: Allow to ignore checksum checking by @WojciechMula [#572](https://github.com/klauspost/compress/pull/572)
* s2: Fix incorrect seek for io.SeekEnd in [#575](https://github.com/klauspost/compress/pull/575)
* Apr 26, 2022 (v1.15.2)
* zstd: Add x86-64 assembly for decompression on streams and blocks. Contributed by [@WojciechMula](https://github.com/WojciechMula). Typically 2x faster. [#528](https://github.com/klauspost/compress/pull/528) [#531](https://github.com/klauspost/compress/pull/531) [#545](https://github.com/klauspost/compress/pull/545) [#537](https://github.com/klauspost/compress/pull/537)
* zstd: Add options to ZipDecompressor and fixes [#539](https://github.com/klauspost/compress/pull/539)
* s2: Use sorted search for index [#555](https://github.com/klauspost/compress/pull/555)
* Minimum version is Go 1.16, added CI test on 1.18.
* Mar 11, 2022 (v1.15.1)
* huff0: Add x86 assembly of Decode4X by @WojciechMula in [#512](https://github.com/klauspost/compress/pull/512)
* zstd: Reuse zip decoders in [#514](https://github.com/klauspost/compress/pull/514)
* zstd: Detect extra block data and report as corrupted in [#520](https://github.com/klauspost/compress/pull/520)
* zstd: Handle zero sized frame content size stricter in [#521](https://github.com/klauspost/compress/pull/521)
* zstd: Add stricter block size checks in [#523](https://github.com/klauspost/compress/pull/523)
* Mar 3, 2022 (v1.15.0)
* zstd: Refactor decoder by @klauspost in [#498](https://github.com/klauspost/compress/pull/498)
* zstd: Add stream encoding without goroutines by @klauspost in [#505](https://github.com/klauspost/compress/pull/505)
@ -60,6 +126,9 @@ While the release has been extensively tested, it is recommended to testing when
* zstd: add arm64 xxhash assembly in [#464](https://github.com/klauspost/compress/pull/464)
* Add garbled for binaries for s2 in [#445](https://github.com/klauspost/compress/pull/445)
<details>
<summary>See changes to v1.13.x</summary>
* Aug 30, 2021 (v1.13.5)
* gz/zlib/flate: Alias stdlib errors [#425](https://github.com/klauspost/compress/pull/425)
* s2: Add block support to commandline tools [#413](https://github.com/klauspost/compress/pull/413)
@ -88,6 +157,8 @@ While the release has been extensively tested, it is recommended to testing when
* Added [gzhttp](https://github.com/klauspost/compress/tree/master/gzhttp#gzip-handler) which allows wrapping HTTP servers and clients with GZIP compressors.
* zstd: Detect short invalid signatures [#382](https://github.com/klauspost/compress/pull/382)
* zstd: Spawn decoder goroutine only if needed. [#380](https://github.com/klauspost/compress/pull/380)
</details>
<details>
<summary>See changes to v1.12.x</summary>

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@ -1,5 +0,0 @@
package huff0
//go:generate go run generate.go
//go:generate asmfmt -w decompress_amd64.s
//go:generate asmfmt -w decompress_8b_amd64.s

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@ -165,11 +165,6 @@ func (b *bitReaderShifted) peekBitsFast(n uint8) uint16 {
return uint16(b.value >> ((64 - n) & 63))
}
// peekTopBits(n) is equvialent to peekBitFast(64 - n)
func (b *bitReaderShifted) peekTopBits(n uint8) uint16 {
return uint16(b.value >> n)
}
func (b *bitReaderShifted) advance(n uint8) {
b.bitsRead += n
b.value <<= n & 63
@ -220,11 +215,6 @@ func (b *bitReaderShifted) fill() {
}
}
// finished returns true if all bits have been read from the bit stream.
func (b *bitReaderShifted) finished() bool {
return b.off == 0 && b.bitsRead >= 64
}
func (b *bitReaderShifted) remaining() uint {
return b.off*8 + uint(64-b.bitsRead)
}

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@ -5,8 +5,6 @@
package huff0
import "fmt"
// bitWriter will write bits.
// First bit will be LSB of the first byte of output.
type bitWriter struct {
@ -23,14 +21,6 @@ var bitMask16 = [32]uint16{
0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF, 0xFFFF,
0xFFFF, 0xFFFF} /* up to 16 bits */
// addBits16NC will add up to 16 bits.
// It will not check if there is space for them,
// so the caller must ensure that it has flushed recently.
func (b *bitWriter) addBits16NC(value uint16, bits uint8) {
b.bitContainer |= uint64(value&bitMask16[bits&31]) << (b.nBits & 63)
b.nBits += bits
}
// addBits16Clean will add up to 16 bits. value may not contain more set bits than indicated.
// It will not check if there is space for them, so the caller must ensure that it has flushed recently.
func (b *bitWriter) addBits16Clean(value uint16, bits uint8) {
@ -70,104 +60,6 @@ func (b *bitWriter) encTwoSymbols(ct cTable, av, bv byte) {
b.nBits += encA.nBits + encB.nBits
}
// addBits16ZeroNC will add up to 16 bits.
// It will not check if there is space for them,
// so the caller must ensure that it has flushed recently.
// This is fastest if bits can be zero.
func (b *bitWriter) addBits16ZeroNC(value uint16, bits uint8) {
if bits == 0 {
return
}
value <<= (16 - bits) & 15
value >>= (16 - bits) & 15
b.bitContainer |= uint64(value) << (b.nBits & 63)
b.nBits += bits
}
// flush will flush all pending full bytes.
// There will be at least 56 bits available for writing when this has been called.
// Using flush32 is faster, but leaves less space for writing.
func (b *bitWriter) flush() {
v := b.nBits >> 3
switch v {
case 0:
return
case 1:
b.out = append(b.out,
byte(b.bitContainer),
)
b.bitContainer >>= 1 << 3
case 2:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
)
b.bitContainer >>= 2 << 3
case 3:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
)
b.bitContainer >>= 3 << 3
case 4:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
)
b.bitContainer >>= 4 << 3
case 5:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
)
b.bitContainer >>= 5 << 3
case 6:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
byte(b.bitContainer>>40),
)
b.bitContainer >>= 6 << 3
case 7:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
byte(b.bitContainer>>40),
byte(b.bitContainer>>48),
)
b.bitContainer >>= 7 << 3
case 8:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
byte(b.bitContainer>>40),
byte(b.bitContainer>>48),
byte(b.bitContainer>>56),
)
b.bitContainer = 0
b.nBits = 0
return
default:
panic(fmt.Errorf("bits (%d) > 64", b.nBits))
}
b.nBits &= 7
}
// flush32 will flush out, so there are at least 32 bits available for writing.
func (b *bitWriter) flush32() {
if b.nBits < 32 {
@ -201,10 +93,3 @@ func (b *bitWriter) close() error {
b.flushAlign()
return nil
}
// reset and continue writing by appending to out.
func (b *bitWriter) reset(out []byte) {
b.bitContainer = 0
b.nBits = 0
b.out = out
}

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@ -20,11 +20,6 @@ func (b *byteReader) init(in []byte) {
b.off = 0
}
// advance the stream b n bytes.
func (b *byteReader) advance(n uint) {
b.off += int(n)
}
// Int32 returns a little endian int32 starting at current offset.
func (b byteReader) Int32() int32 {
v3 := int32(b.b[b.off+3])
@ -43,11 +38,6 @@ func (b byteReader) Uint32() uint32 {
return (v3 << 24) | (v2 << 16) | (v1 << 8) | v0
}
// unread returns the unread portion of the input.
func (b byteReader) unread() []byte {
return b.b[b.off:]
}
// remain will return the number of bytes remaining.
func (b byteReader) remain() int {
return len(b.b) - b.off

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@ -404,6 +404,7 @@ func (s *Scratch) canUseTable(c cTable) bool {
return true
}
//lint:ignore U1000 used for debugging
func (s *Scratch) validateTable(c cTable) bool {
if len(c) < int(s.symbolLen) {
return false

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@ -11,7 +11,6 @@ import (
type dTable struct {
single []dEntrySingle
double []dEntryDouble
}
// single-symbols decoding
@ -19,13 +18,6 @@ type dEntrySingle struct {
entry uint16
}
// double-symbols decoding
type dEntryDouble struct {
seq [4]byte
nBits uint8
len uint8
}
// Uses special code for all tables that are < 8 bits.
const use8BitTables = true
@ -35,7 +27,7 @@ const use8BitTables = true
// If no Scratch is provided a new one is allocated.
// The returned Scratch can be used for encoding or decoding input using this table.
func ReadTable(in []byte, s *Scratch) (s2 *Scratch, remain []byte, err error) {
s, err = s.prepare(in)
s, err = s.prepare(nil)
if err != nil {
return s, nil, err
}
@ -236,108 +228,6 @@ func (d *Decoder) buffer() *[4][256]byte {
return &[4][256]byte{}
}
// Decompress1X will decompress a 1X encoded stream.
// The cap of the output buffer will be the maximum decompressed size.
// The length of the supplied input must match the end of a block exactly.
func (d *Decoder) Decompress1X(dst, src []byte) ([]byte, error) {
if len(d.dt.single) == 0 {
return nil, errors.New("no table loaded")
}
if use8BitTables && d.actualTableLog <= 8 {
return d.decompress1X8Bit(dst, src)
}
var br bitReaderShifted
err := br.init(src)
if err != nil {
return dst, err
}
maxDecodedSize := cap(dst)
dst = dst[:0]
// Avoid bounds check by always having full sized table.
const tlSize = 1 << tableLogMax
const tlMask = tlSize - 1
dt := d.dt.single[:tlSize]
// Use temp table to avoid bound checks/append penalty.
bufs := d.buffer()
buf := &bufs[0]
var off uint8
for br.off >= 8 {
br.fillFast()
v := dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+0] = uint8(v.entry >> 8)
v = dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+1] = uint8(v.entry >> 8)
// Refill
br.fillFast()
v = dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+2] = uint8(v.entry >> 8)
v = dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+3] = uint8(v.entry >> 8)
off += 4
if off == 0 {
if len(dst)+256 > maxDecodedSize {
br.close()
d.bufs.Put(bufs)
return nil, ErrMaxDecodedSizeExceeded
}
dst = append(dst, buf[:]...)
}
}
if len(dst)+int(off) > maxDecodedSize {
d.bufs.Put(bufs)
br.close()
return nil, ErrMaxDecodedSizeExceeded
}
dst = append(dst, buf[:off]...)
// br < 8, so uint8 is fine
bitsLeft := uint8(br.off)*8 + 64 - br.bitsRead
for bitsLeft > 0 {
br.fill()
if false && br.bitsRead >= 32 {
if br.off >= 4 {
v := br.in[br.off-4:]
v = v[:4]
low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
br.value = (br.value << 32) | uint64(low)
br.bitsRead -= 32
br.off -= 4
} else {
for br.off > 0 {
br.value = (br.value << 8) | uint64(br.in[br.off-1])
br.bitsRead -= 8
br.off--
}
}
}
if len(dst) >= maxDecodedSize {
d.bufs.Put(bufs)
br.close()
return nil, ErrMaxDecodedSizeExceeded
}
v := d.dt.single[br.peekBitsFast(d.actualTableLog)&tlMask]
nBits := uint8(v.entry)
br.advance(nBits)
bitsLeft -= nBits
dst = append(dst, uint8(v.entry>>8))
}
d.bufs.Put(bufs)
return dst, br.close()
}
// decompress1X8Bit will decompress a 1X encoded stream with tablelog <= 8.
// The cap of the output buffer will be the maximum decompressed size.
// The length of the supplied input must match the end of a block exactly.
@ -995,7 +885,6 @@ func (d *Decoder) decompress4X8bitExactly(dst, src []byte) ([]byte, error) {
const shift = 56
const tlSize = 1 << 8
const tlMask = tlSize - 1
single := d.dt.single[:tlSize]
// Use temp table to avoid bound checks/append penalty.

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@ -1,488 +0,0 @@
// +build !appengine
// +build gc
// +build !noasm
#include "textflag.h"
#include "funcdata.h"
#include "go_asm.h"
#define bufoff 256 // see decompress.go, we're using [4][256]byte table
// func decompress4x_main_loop_x86(pbr0, pbr1, pbr2, pbr3 *bitReaderShifted,
// peekBits uint8, buf *byte, tbl *dEntrySingle) (int, bool)
TEXT ·decompress4x_8b_loop_x86(SB), NOSPLIT, $8
#define off R8
#define buffer DI
#define table SI
#define br_bits_read R9
#define br_value R10
#define br_offset R11
#define peek_bits R12
#define exhausted DX
#define br0 R13
#define br1 R14
#define br2 R15
#define br3 BP
MOVQ BP, 0(SP)
XORQ exhausted, exhausted // exhausted = false
XORQ off, off // off = 0
MOVBQZX peekBits+32(FP), peek_bits
MOVQ buf+40(FP), buffer
MOVQ tbl+48(FP), table
MOVQ pbr0+0(FP), br0
MOVQ pbr1+8(FP), br1
MOVQ pbr2+16(FP), br2
MOVQ pbr3+24(FP), br3
main_loop:
// const stream = 0
// br0.fillFast()
MOVBQZX bitReaderShifted_bitsRead(br0), br_bits_read
MOVQ bitReaderShifted_value(br0), br_value
MOVQ bitReaderShifted_off(br0), br_offset
// if b.bitsRead >= 32 {
CMPQ br_bits_read, $32
JB skip_fill0
SUBQ $32, br_bits_read // b.bitsRead -= 32
SUBQ $4, br_offset // b.off -= 4
// v := b.in[b.off-4 : b.off]
// v = v[:4]
// low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
MOVQ bitReaderShifted_in(br0), AX
MOVL 0(br_offset)(AX*1), AX // AX = uint32(b.in[b.off:b.off+4])
// b.value |= uint64(low) << (b.bitsRead & 63)
MOVQ br_bits_read, CX
SHLQ CL, AX
ORQ AX, br_value
// exhausted = exhausted || (br0.off < 4)
CMPQ br_offset, $4
SETLT DL
ORB DL, DH
// }
skip_fill0:
// val0 := br0.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v0 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br0.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val1 := br0.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v1 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br0.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off] = uint8(v0.entry >> 8)
// buf[stream][off+1] = uint8(v1.entry >> 8)
MOVW BX, 0(buffer)(off*1)
// SECOND PART:
// val2 := br0.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v2 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br0.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val3 := br0.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v3 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br0.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off+2] = uint8(v2.entry >> 8)
// buf[stream][off+3] = uint8(v3.entry >> 8)
MOVW BX, 0+2(buffer)(off*1)
// update the bitrader reader structure
MOVB br_bits_read, bitReaderShifted_bitsRead(br0)
MOVQ br_value, bitReaderShifted_value(br0)
MOVQ br_offset, bitReaderShifted_off(br0)
// const stream = 1
// br1.fillFast()
MOVBQZX bitReaderShifted_bitsRead(br1), br_bits_read
MOVQ bitReaderShifted_value(br1), br_value
MOVQ bitReaderShifted_off(br1), br_offset
// if b.bitsRead >= 32 {
CMPQ br_bits_read, $32
JB skip_fill1
SUBQ $32, br_bits_read // b.bitsRead -= 32
SUBQ $4, br_offset // b.off -= 4
// v := b.in[b.off-4 : b.off]
// v = v[:4]
// low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
MOVQ bitReaderShifted_in(br1), AX
MOVL 0(br_offset)(AX*1), AX // AX = uint32(b.in[b.off:b.off+4])
// b.value |= uint64(low) << (b.bitsRead & 63)
MOVQ br_bits_read, CX
SHLQ CL, AX
ORQ AX, br_value
// exhausted = exhausted || (br1.off < 4)
CMPQ br_offset, $4
SETLT DL
ORB DL, DH
// }
skip_fill1:
// val0 := br1.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v0 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br1.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val1 := br1.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v1 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br1.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off] = uint8(v0.entry >> 8)
// buf[stream][off+1] = uint8(v1.entry >> 8)
MOVW BX, 256(buffer)(off*1)
// SECOND PART:
// val2 := br1.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v2 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br1.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val3 := br1.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v3 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br1.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off+2] = uint8(v2.entry >> 8)
// buf[stream][off+3] = uint8(v3.entry >> 8)
MOVW BX, 256+2(buffer)(off*1)
// update the bitrader reader structure
MOVB br_bits_read, bitReaderShifted_bitsRead(br1)
MOVQ br_value, bitReaderShifted_value(br1)
MOVQ br_offset, bitReaderShifted_off(br1)
// const stream = 2
// br2.fillFast()
MOVBQZX bitReaderShifted_bitsRead(br2), br_bits_read
MOVQ bitReaderShifted_value(br2), br_value
MOVQ bitReaderShifted_off(br2), br_offset
// if b.bitsRead >= 32 {
CMPQ br_bits_read, $32
JB skip_fill2
SUBQ $32, br_bits_read // b.bitsRead -= 32
SUBQ $4, br_offset // b.off -= 4
// v := b.in[b.off-4 : b.off]
// v = v[:4]
// low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
MOVQ bitReaderShifted_in(br2), AX
MOVL 0(br_offset)(AX*1), AX // AX = uint32(b.in[b.off:b.off+4])
// b.value |= uint64(low) << (b.bitsRead & 63)
MOVQ br_bits_read, CX
SHLQ CL, AX
ORQ AX, br_value
// exhausted = exhausted || (br2.off < 4)
CMPQ br_offset, $4
SETLT DL
ORB DL, DH
// }
skip_fill2:
// val0 := br2.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v0 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br2.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val1 := br2.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v1 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br2.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off] = uint8(v0.entry >> 8)
// buf[stream][off+1] = uint8(v1.entry >> 8)
MOVW BX, 512(buffer)(off*1)
// SECOND PART:
// val2 := br2.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v2 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br2.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val3 := br2.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v3 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br2.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off+2] = uint8(v2.entry >> 8)
// buf[stream][off+3] = uint8(v3.entry >> 8)
MOVW BX, 512+2(buffer)(off*1)
// update the bitrader reader structure
MOVB br_bits_read, bitReaderShifted_bitsRead(br2)
MOVQ br_value, bitReaderShifted_value(br2)
MOVQ br_offset, bitReaderShifted_off(br2)
// const stream = 3
// br3.fillFast()
MOVBQZX bitReaderShifted_bitsRead(br3), br_bits_read
MOVQ bitReaderShifted_value(br3), br_value
MOVQ bitReaderShifted_off(br3), br_offset
// if b.bitsRead >= 32 {
CMPQ br_bits_read, $32
JB skip_fill3
SUBQ $32, br_bits_read // b.bitsRead -= 32
SUBQ $4, br_offset // b.off -= 4
// v := b.in[b.off-4 : b.off]
// v = v[:4]
// low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
MOVQ bitReaderShifted_in(br3), AX
MOVL 0(br_offset)(AX*1), AX // AX = uint32(b.in[b.off:b.off+4])
// b.value |= uint64(low) << (b.bitsRead & 63)
MOVQ br_bits_read, CX
SHLQ CL, AX
ORQ AX, br_value
// exhausted = exhausted || (br3.off < 4)
CMPQ br_offset, $4
SETLT DL
ORB DL, DH
// }
skip_fill3:
// val0 := br3.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v0 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br3.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val1 := br3.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v1 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br3.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off] = uint8(v0.entry >> 8)
// buf[stream][off+1] = uint8(v1.entry >> 8)
MOVW BX, 768(buffer)(off*1)
// SECOND PART:
// val2 := br3.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v2 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br3.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val3 := br3.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v3 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br3.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off+2] = uint8(v2.entry >> 8)
// buf[stream][off+3] = uint8(v3.entry >> 8)
MOVW BX, 768+2(buffer)(off*1)
// update the bitrader reader structure
MOVB br_bits_read, bitReaderShifted_bitsRead(br3)
MOVQ br_value, bitReaderShifted_value(br3)
MOVQ br_offset, bitReaderShifted_off(br3)
ADDQ $4, off // off += 2
TESTB DH, DH // any br[i].ofs < 4?
JNZ end
CMPQ off, $bufoff
JL main_loop
end:
MOVQ 0(SP), BP
MOVB off, ret+56(FP)
RET
#undef off
#undef buffer
#undef table
#undef br_bits_read
#undef br_value
#undef br_offset
#undef peek_bits
#undef exhausted
#undef br0
#undef br1
#undef br2
#undef br3

View File

@ -1,197 +0,0 @@
// +build !appengine
// +build gc
// +build !noasm
#include "textflag.h"
#include "funcdata.h"
#include "go_asm.h"
#define bufoff 256 // see decompress.go, we're using [4][256]byte table
//func decompress4x_main_loop_x86(pbr0, pbr1, pbr2, pbr3 *bitReaderShifted,
// peekBits uint8, buf *byte, tbl *dEntrySingle) (int, bool)
TEXT ·decompress4x_8b_loop_x86(SB), NOSPLIT, $8
#define off R8
#define buffer DI
#define table SI
#define br_bits_read R9
#define br_value R10
#define br_offset R11
#define peek_bits R12
#define exhausted DX
#define br0 R13
#define br1 R14
#define br2 R15
#define br3 BP
MOVQ BP, 0(SP)
XORQ exhausted, exhausted // exhausted = false
XORQ off, off // off = 0
MOVBQZX peekBits+32(FP), peek_bits
MOVQ buf+40(FP), buffer
MOVQ tbl+48(FP), table
MOVQ pbr0+0(FP), br0
MOVQ pbr1+8(FP), br1
MOVQ pbr2+16(FP), br2
MOVQ pbr3+24(FP), br3
main_loop:
{{ define "decode_2_values_x86" }}
// const stream = {{ var "id" }}
// br{{ var "id"}}.fillFast()
MOVBQZX bitReaderShifted_bitsRead(br{{ var "id" }}), br_bits_read
MOVQ bitReaderShifted_value(br{{ var "id" }}), br_value
MOVQ bitReaderShifted_off(br{{ var "id" }}), br_offset
// if b.bitsRead >= 32 {
CMPQ br_bits_read, $32
JB skip_fill{{ var "id" }}
SUBQ $32, br_bits_read // b.bitsRead -= 32
SUBQ $4, br_offset // b.off -= 4
// v := b.in[b.off-4 : b.off]
// v = v[:4]
// low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
MOVQ bitReaderShifted_in(br{{ var "id" }}), AX
MOVL 0(br_offset)(AX*1), AX // AX = uint32(b.in[b.off:b.off+4])
// b.value |= uint64(low) << (b.bitsRead & 63)
MOVQ br_bits_read, CX
SHLQ CL, AX
ORQ AX, br_value
// exhausted = exhausted || (br{{ var "id"}}.off < 4)
CMPQ br_offset, $4
SETLT DL
ORB DL, DH
// }
skip_fill{{ var "id" }}:
// val0 := br{{ var "id"}}.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v0 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br{{ var "id"}}.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val1 := br{{ var "id"}}.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v1 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br{{ var "id"}}.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off] = uint8(v0.entry >> 8)
// buf[stream][off+1] = uint8(v1.entry >> 8)
MOVW BX, {{ var "bufofs" }}(buffer)(off*1)
// SECOND PART:
// val2 := br{{ var "id"}}.peekTopBits(peekBits)
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v2 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br{{ var "id"}}.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// val3 := br{{ var "id"}}.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
// v3 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br{{ var "id"}}.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
MOVBQZX AL, CX
SHLQ CX, br_value // value <<= n
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off+2] = uint8(v2.entry >> 8)
// buf[stream][off+3] = uint8(v3.entry >> 8)
MOVW BX, {{ var "bufofs" }}+2(buffer)(off*1)
// update the bitrader reader structure
MOVB br_bits_read, bitReaderShifted_bitsRead(br{{ var "id" }})
MOVQ br_value, bitReaderShifted_value(br{{ var "id" }})
MOVQ br_offset, bitReaderShifted_off(br{{ var "id" }})
{{ end }}
{{ set "id" "0" }}
{{ set "ofs" "0" }}
{{ set "bufofs" "0" }} {{/* id * bufoff */}}
{{ template "decode_2_values_x86" . }}
{{ set "id" "1" }}
{{ set "ofs" "8" }}
{{ set "bufofs" "256" }}
{{ template "decode_2_values_x86" . }}
{{ set "id" "2" }}
{{ set "ofs" "16" }}
{{ set "bufofs" "512" }}
{{ template "decode_2_values_x86" . }}
{{ set "id" "3" }}
{{ set "ofs" "24" }}
{{ set "bufofs" "768" }}
{{ template "decode_2_values_x86" . }}
ADDQ $4, off // off += 2
TESTB DH, DH // any br[i].ofs < 4?
JNZ end
CMPQ off, $bufoff
JL main_loop
end:
MOVQ 0(SP), BP
MOVB off, ret+56(FP)
RET
#undef off
#undef buffer
#undef table
#undef br_bits_read
#undef br_value
#undef br_offset
#undef peek_bits
#undef exhausted
#undef br0
#undef br1
#undef br2
#undef br3

View File

@ -2,30 +2,40 @@
// +build amd64,!appengine,!noasm,gc
// This file contains the specialisation of Decoder.Decompress4X
// that uses an asm implementation of its main loop.
// and Decoder.Decompress1X that use an asm implementation of thir main loops.
package huff0
import (
"errors"
"fmt"
"github.com/klauspost/compress/internal/cpuinfo"
)
// decompress4x_main_loop_x86 is an x86 assembler implementation
// of Decompress4X when tablelog > 8.
// go:noescape
func decompress4x_main_loop_x86(pbr0, pbr1, pbr2, pbr3 *bitReaderShifted,
peekBits uint8, buf *byte, tbl *dEntrySingle) uint8
//go:noescape
func decompress4x_main_loop_amd64(ctx *decompress4xContext)
// decompress4x_8b_loop_x86 is an x86 assembler implementation
// of Decompress4X when tablelog <= 8 which decodes 4 entries
// per loop.
// go:noescape
func decompress4x_8b_loop_x86(pbr0, pbr1, pbr2, pbr3 *bitReaderShifted,
peekBits uint8, buf *byte, tbl *dEntrySingle) uint8
//go:noescape
func decompress4x_8b_main_loop_amd64(ctx *decompress4xContext)
// fallback8BitSize is the size where using Go version is faster.
const fallback8BitSize = 800
type decompress4xContext struct {
pbr *[4]bitReaderShifted
peekBits uint8
out *byte
dstEvery int
tbl *dEntrySingle
decoded int
limit *byte
}
// Decompress4X will decompress a 4X encoded stream.
// The length of the supplied input must match the end of a block exactly.
// The *capacity* of the dst slice must match the destination size of
@ -42,6 +52,7 @@ func (d *Decoder) Decompress4X(dst, src []byte) ([]byte, error) {
if cap(dst) < fallback8BitSize && use8BitTables {
return d.decompress4X8bit(dst, src)
}
var br [4]bitReaderShifted
// Decode "jump table"
start := 6
@ -71,70 +82,25 @@ func (d *Decoder) Decompress4X(dst, src []byte) ([]byte, error) {
const tlMask = tlSize - 1
single := d.dt.single[:tlSize]
// Use temp table to avoid bound checks/append penalty.
buf := d.buffer()
var off uint8
var decoded int
const debug = false
// see: bitReaderShifted.peekBitsFast()
peekBits := uint8((64 - d.actualTableLog) & 63)
// Decode 2 values from each decoder/loop.
const bufoff = 256
for {
if br[0].off < 4 || br[1].off < 4 || br[2].off < 4 || br[3].off < 4 {
break
if len(out) > 4*4 && !(br[0].off < 4 || br[1].off < 4 || br[2].off < 4 || br[3].off < 4) {
ctx := decompress4xContext{
pbr: &br,
peekBits: uint8((64 - d.actualTableLog) & 63), // see: bitReaderShifted.peekBitsFast()
out: &out[0],
dstEvery: dstEvery,
tbl: &single[0],
limit: &out[dstEvery-4], // Always stop decoding when first buffer gets here to avoid writing OOB on last.
}
if use8BitTables {
off = decompress4x_8b_loop_x86(&br[0], &br[1], &br[2], &br[3], peekBits, &buf[0][0], &single[0])
decompress4x_8b_main_loop_amd64(&ctx)
} else {
off = decompress4x_main_loop_x86(&br[0], &br[1], &br[2], &br[3], peekBits, &buf[0][0], &single[0])
}
if debug {
fmt.Print("DEBUG: ")
fmt.Printf("off=%d,", off)
for i := 0; i < 4; i++ {
fmt.Printf(" br[%d]={bitsRead=%d, value=%x, off=%d}",
i, br[i].bitsRead, br[i].value, br[i].off)
}
fmt.Println("")
decompress4x_main_loop_amd64(&ctx)
}
if off != 0 {
break
}
if bufoff > dstEvery {
d.bufs.Put(buf)
return nil, errors.New("corruption detected: stream overrun 1")
}
copy(out, buf[0][:])
copy(out[dstEvery:], buf[1][:])
copy(out[dstEvery*2:], buf[2][:])
copy(out[dstEvery*3:], buf[3][:])
out = out[bufoff:]
decoded += bufoff * 4
// There must at least be 3 buffers left.
if len(out) < dstEvery*3 {
d.bufs.Put(buf)
return nil, errors.New("corruption detected: stream overrun 2")
}
}
if off > 0 {
ioff := int(off)
if len(out) < dstEvery*3+ioff {
d.bufs.Put(buf)
return nil, errors.New("corruption detected: stream overrun 3")
}
copy(out, buf[0][:off])
copy(out[dstEvery:], buf[1][:off])
copy(out[dstEvery*2:], buf[2][:off])
copy(out[dstEvery*3:], buf[3][:off])
decoded += int(off) * 4
out = out[off:]
decoded = ctx.decoded
out = out[decoded/4:]
}
// Decode remaining.
@ -150,7 +116,6 @@ func (d *Decoder) Decompress4X(dst, src []byte) ([]byte, error) {
for bitsLeft > 0 {
br.fill()
if offset >= endsAt {
d.bufs.Put(buf)
return nil, errors.New("corruption detected: stream overrun 4")
}
@ -164,7 +129,6 @@ func (d *Decoder) Decompress4X(dst, src []byte) ([]byte, error) {
offset++
}
if offset != endsAt {
d.bufs.Put(buf)
return nil, fmt.Errorf("corruption detected: short output block %d, end %d != %d", i, offset, endsAt)
}
decoded += offset - dstEvery*i
@ -173,9 +137,86 @@ func (d *Decoder) Decompress4X(dst, src []byte) ([]byte, error) {
return nil, err
}
}
d.bufs.Put(buf)
if dstSize != decoded {
return nil, errors.New("corruption detected: short output block")
}
return dst, nil
}
// decompress4x_main_loop_x86 is an x86 assembler implementation
// of Decompress1X when tablelog > 8.
//go:noescape
func decompress1x_main_loop_amd64(ctx *decompress1xContext)
// decompress4x_main_loop_x86 is an x86 with BMI2 assembler implementation
// of Decompress1X when tablelog > 8.
//go:noescape
func decompress1x_main_loop_bmi2(ctx *decompress1xContext)
type decompress1xContext struct {
pbr *bitReaderShifted
peekBits uint8
out *byte
outCap int
tbl *dEntrySingle
decoded int
}
// Error reported by asm implementations
const error_max_decoded_size_exeeded = -1
// Decompress1X will decompress a 1X encoded stream.
// The cap of the output buffer will be the maximum decompressed size.
// The length of the supplied input must match the end of a block exactly.
func (d *Decoder) Decompress1X(dst, src []byte) ([]byte, error) {
if len(d.dt.single) == 0 {
return nil, errors.New("no table loaded")
}
var br bitReaderShifted
err := br.init(src)
if err != nil {
return dst, err
}
maxDecodedSize := cap(dst)
dst = dst[:maxDecodedSize]
const tlSize = 1 << tableLogMax
const tlMask = tlSize - 1
if maxDecodedSize >= 4 {
ctx := decompress1xContext{
pbr: &br,
out: &dst[0],
outCap: maxDecodedSize,
peekBits: uint8((64 - d.actualTableLog) & 63), // see: bitReaderShifted.peekBitsFast()
tbl: &d.dt.single[0],
}
if cpuinfo.HasBMI2() {
decompress1x_main_loop_bmi2(&ctx)
} else {
decompress1x_main_loop_amd64(&ctx)
}
if ctx.decoded == error_max_decoded_size_exeeded {
return nil, ErrMaxDecodedSizeExceeded
}
dst = dst[:ctx.decoded]
}
// br < 8, so uint8 is fine
bitsLeft := uint8(br.off)*8 + 64 - br.bitsRead
for bitsLeft > 0 {
br.fill()
if len(dst) >= maxDecodedSize {
br.close()
return nil, ErrMaxDecodedSizeExceeded
}
v := d.dt.single[br.peekBitsFast(d.actualTableLog)&tlMask]
nBits := uint8(v.entry)
br.advance(nBits)
bitsLeft -= nBits
dst = append(dst, uint8(v.entry>>8))
}
return dst, br.close()
}

File diff suppressed because it is too large Load Diff

View File

@ -1,195 +0,0 @@
// +build !appengine
// +build gc
// +build !noasm
#include "textflag.h"
#include "funcdata.h"
#include "go_asm.h"
#ifdef GOAMD64_v4
#ifndef GOAMD64_v3
#define GOAMD64_v3
#endif
#endif
#define bufoff 256 // see decompress.go, we're using [4][256]byte table
//func decompress4x_main_loop_x86(pbr0, pbr1, pbr2, pbr3 *bitReaderShifted,
// peekBits uint8, buf *byte, tbl *dEntrySingle) (int, bool)
TEXT ·decompress4x_main_loop_x86(SB), NOSPLIT, $8
#define off R8
#define buffer DI
#define table SI
#define br_bits_read R9
#define br_value R10
#define br_offset R11
#define peek_bits R12
#define exhausted DX
#define br0 R13
#define br1 R14
#define br2 R15
#define br3 BP
MOVQ BP, 0(SP)
XORQ exhausted, exhausted // exhausted = false
XORQ off, off // off = 0
MOVBQZX peekBits+32(FP), peek_bits
MOVQ buf+40(FP), buffer
MOVQ tbl+48(FP), table
MOVQ pbr0+0(FP), br0
MOVQ pbr1+8(FP), br1
MOVQ pbr2+16(FP), br2
MOVQ pbr3+24(FP), br3
main_loop:
{{ define "decode_2_values_x86" }}
// const stream = {{ var "id" }}
// br{{ var "id"}}.fillFast()
MOVBQZX bitReaderShifted_bitsRead(br{{ var "id" }}), br_bits_read
MOVQ bitReaderShifted_value(br{{ var "id" }}), br_value
MOVQ bitReaderShifted_off(br{{ var "id" }}), br_offset
// We must have at least 2 * max tablelog left
CMPQ br_bits_read, $64-22
JBE skip_fill{{ var "id" }}
SUBQ $32, br_bits_read // b.bitsRead -= 32
SUBQ $4, br_offset // b.off -= 4
// v := b.in[b.off-4 : b.off]
// v = v[:4]
// low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
MOVQ bitReaderShifted_in(br{{ var "id" }}), AX
// b.value |= uint64(low) << (b.bitsRead & 63)
#ifdef GOAMD64_v3
SHLXQ br_bits_read, 0(br_offset)(AX*1), AX // AX = uint32(b.in[b.off:b.off+4]) << (b.bitsRead & 63)
#else
MOVL 0(br_offset)(AX*1), AX // AX = uint32(b.in[b.off:b.off+4])
MOVQ br_bits_read, CX
SHLQ CL, AX
#endif
ORQ AX, br_value
// exhausted = exhausted || (br{{ var "id"}}.off < 4)
CMPQ br_offset, $4
SETLT DL
ORB DL, DH
// }
skip_fill{{ var "id" }}:
// val0 := br{{ var "id"}}.peekTopBits(peekBits)
#ifdef GOAMD64_v3
SHRXQ peek_bits, br_value, AX // AX = (value >> peek_bits) & mask
#else
MOVQ br_value, AX
MOVQ peek_bits, CX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
#endif
// v0 := table[val0&mask]
MOVW 0(table)(AX*2), AX // AX - v0
// br{{ var "id"}}.advance(uint8(v0.entry))
MOVB AH, BL // BL = uint8(v0.entry >> 8)
#ifdef GOAMD64_v3
MOVBQZX AL, CX
SHLXQ AX, br_value, br_value // value <<= n
#else
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
#endif
ADDQ CX, br_bits_read // bits_read += n
#ifdef GOAMD64_v3
SHRXQ peek_bits, br_value, AX // AX = (value >> peek_bits) & mask
#else
// val1 := br{{ var "id"}}.peekTopBits(peekBits)
MOVQ peek_bits, CX
MOVQ br_value, AX
SHRQ CL, AX // AX = (value >> peek_bits) & mask
#endif
// v1 := table[val1&mask]
MOVW 0(table)(AX*2), AX // AX - v1
// br{{ var "id"}}.advance(uint8(v1.entry))
MOVB AH, BH // BH = uint8(v1.entry >> 8)
#ifdef GOAMD64_v3
MOVBQZX AL, CX
SHLXQ AX, br_value, br_value // value <<= n
#else
MOVBQZX AL, CX
SHLQ CL, br_value // value <<= n
#endif
ADDQ CX, br_bits_read // bits_read += n
// these two writes get coalesced
// buf[stream][off] = uint8(v0.entry >> 8)
// buf[stream][off+1] = uint8(v1.entry >> 8)
MOVW BX, {{ var "bufofs" }}(buffer)(off*1)
// update the bitrader reader structure
MOVB br_bits_read, bitReaderShifted_bitsRead(br{{ var "id" }})
MOVQ br_value, bitReaderShifted_value(br{{ var "id" }})
MOVQ br_offset, bitReaderShifted_off(br{{ var "id" }})
{{ end }}
{{ set "id" "0" }}
{{ set "ofs" "0" }}
{{ set "bufofs" "0" }} {{/* id * bufoff */}}
{{ template "decode_2_values_x86" . }}
{{ set "id" "1" }}
{{ set "ofs" "8" }}
{{ set "bufofs" "256" }}
{{ template "decode_2_values_x86" . }}
{{ set "id" "2" }}
{{ set "ofs" "16" }}
{{ set "bufofs" "512" }}
{{ template "decode_2_values_x86" . }}
{{ set "id" "3" }}
{{ set "ofs" "24" }}
{{ set "bufofs" "768" }}
{{ template "decode_2_values_x86" . }}
ADDQ $2, off // off += 2
TESTB DH, DH // any br[i].ofs < 4?
JNZ end
CMPQ off, $bufoff
JL main_loop
end:
MOVQ 0(SP), BP
MOVB off, ret+56(FP)
RET
#undef off
#undef buffer
#undef table
#undef br_bits_read
#undef br_value
#undef br_offset
#undef peek_bits
#undef exhausted
#undef br0
#undef br1
#undef br2
#undef br3

View File

@ -191,3 +191,105 @@ func (d *Decoder) Decompress4X(dst, src []byte) ([]byte, error) {
}
return dst, nil
}
// Decompress1X will decompress a 1X encoded stream.
// The cap of the output buffer will be the maximum decompressed size.
// The length of the supplied input must match the end of a block exactly.
func (d *Decoder) Decompress1X(dst, src []byte) ([]byte, error) {
if len(d.dt.single) == 0 {
return nil, errors.New("no table loaded")
}
if use8BitTables && d.actualTableLog <= 8 {
return d.decompress1X8Bit(dst, src)
}
var br bitReaderShifted
err := br.init(src)
if err != nil {
return dst, err
}
maxDecodedSize := cap(dst)
dst = dst[:0]
// Avoid bounds check by always having full sized table.
const tlSize = 1 << tableLogMax
const tlMask = tlSize - 1
dt := d.dt.single[:tlSize]
// Use temp table to avoid bound checks/append penalty.
bufs := d.buffer()
buf := &bufs[0]
var off uint8
for br.off >= 8 {
br.fillFast()
v := dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+0] = uint8(v.entry >> 8)
v = dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+1] = uint8(v.entry >> 8)
// Refill
br.fillFast()
v = dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+2] = uint8(v.entry >> 8)
v = dt[br.peekBitsFast(d.actualTableLog)&tlMask]
br.advance(uint8(v.entry))
buf[off+3] = uint8(v.entry >> 8)
off += 4
if off == 0 {
if len(dst)+256 > maxDecodedSize {
br.close()
d.bufs.Put(bufs)
return nil, ErrMaxDecodedSizeExceeded
}
dst = append(dst, buf[:]...)
}
}
if len(dst)+int(off) > maxDecodedSize {
d.bufs.Put(bufs)
br.close()
return nil, ErrMaxDecodedSizeExceeded
}
dst = append(dst, buf[:off]...)
// br < 8, so uint8 is fine
bitsLeft := uint8(br.off)*8 + 64 - br.bitsRead
for bitsLeft > 0 {
br.fill()
if false && br.bitsRead >= 32 {
if br.off >= 4 {
v := br.in[br.off-4:]
v = v[:4]
low := (uint32(v[0])) | (uint32(v[1]) << 8) | (uint32(v[2]) << 16) | (uint32(v[3]) << 24)
br.value = (br.value << 32) | uint64(low)
br.bitsRead -= 32
br.off -= 4
} else {
for br.off > 0 {
br.value = (br.value << 8) | uint64(br.in[br.off-1])
br.bitsRead -= 8
br.off--
}
}
}
if len(dst) >= maxDecodedSize {
d.bufs.Put(bufs)
br.close()
return nil, ErrMaxDecodedSizeExceeded
}
v := d.dt.single[br.peekBitsFast(d.actualTableLog)&tlMask]
nBits := uint8(v.entry)
br.advance(nBits)
bitsLeft -= nBits
dst = append(dst, uint8(v.entry>>8))
}
d.bufs.Put(bufs)
return dst, br.close()
}

View File

@ -0,0 +1,34 @@
// Package cpuinfo gives runtime info about the current CPU.
//
// This is a very limited module meant for use internally
// in this project. For more versatile solution check
// https://github.com/klauspost/cpuid.
package cpuinfo
// HasBMI1 checks whether an x86 CPU supports the BMI1 extension.
func HasBMI1() bool {
return hasBMI1
}
// HasBMI2 checks whether an x86 CPU supports the BMI2 extension.
func HasBMI2() bool {
return hasBMI2
}
// DisableBMI2 will disable BMI2, for testing purposes.
// Call returned function to restore previous state.
func DisableBMI2() func() {
old := hasBMI2
hasBMI2 = false
return func() {
hasBMI2 = old
}
}
// HasBMI checks whether an x86 CPU supports both BMI1 and BMI2 extensions.
func HasBMI() bool {
return HasBMI1() && HasBMI2()
}
var hasBMI1 bool
var hasBMI2 bool

View File

@ -0,0 +1,11 @@
//go:build amd64 && !appengine && !noasm && gc
// +build amd64,!appengine,!noasm,gc
package cpuinfo
// go:noescape
func x86extensions() (bmi1, bmi2 bool)
func init() {
hasBMI1, hasBMI2 = x86extensions()
}

View File

@ -0,0 +1,36 @@
// +build !appengine
// +build gc
// +build !noasm
#include "textflag.h"
#include "funcdata.h"
#include "go_asm.h"
TEXT ·x86extensions(SB), NOSPLIT, $0
// 1. determine max EAX value
XORQ AX, AX
CPUID
CMPQ AX, $7
JB unsupported
// 2. EAX = 7, ECX = 0 --- see Table 3-8 "Information Returned by CPUID Instruction"
MOVQ $7, AX
MOVQ $0, CX
CPUID
BTQ $3, BX // bit 3 = BMI1
SETCS AL
BTQ $8, BX // bit 8 = BMI2
SETCS AH
MOVB AL, bmi1+0(FP)
MOVB AH, bmi2+1(FP)
RET
unsupported:
XORQ AX, AX
MOVB AL, bmi1+0(FP)
MOVB AL, bmi2+1(FP)
RET

View File

@ -386,47 +386,31 @@ In practice this means that concurrency is often limited to utilizing about 3 co
### Benchmarks
These are some examples of performance compared to [datadog cgo library](https://github.com/DataDog/zstd).
The first two are streaming decodes and the last are smaller inputs.
Running on AMD Ryzen 9 3950X 16-Core Processor. AMD64 assembly used.
```
BenchmarkDecoderSilesia-8 3 385000067 ns/op 550.51 MB/s 5498 B/op 8 allocs/op
BenchmarkDecoderSilesiaCgo-8 6 197666567 ns/op 1072.25 MB/s 270672 B/op 8 allocs/op
BenchmarkDecoderSilesia-32 5 206878840 ns/op 1024.50 MB/s 49808 B/op 43 allocs/op
BenchmarkDecoderEnwik9-32 1 1271809000 ns/op 786.28 MB/s 72048 B/op 52 allocs/op
BenchmarkDecoderEnwik9-8 1 2027001600 ns/op 493.34 MB/s 10496 B/op 18 allocs/op
BenchmarkDecoderEnwik9Cgo-8 2 979499200 ns/op 1020.93 MB/s 270672 B/op 8 allocs/op
Concurrent blocks, performance:
Concurrent performance:
BenchmarkDecoder_DecodeAllParallel/kppkn.gtb.zst-16 28915 42469 ns/op 4340.07 MB/s 114 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/geo.protodata.zst-16 116505 9965 ns/op 11900.16 MB/s 16 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/plrabn12.txt.zst-16 8952 134272 ns/op 3588.70 MB/s 915 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/lcet10.txt.zst-16 11820 102538 ns/op 4161.90 MB/s 594 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/asyoulik.txt.zst-16 34782 34184 ns/op 3661.88 MB/s 60 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/alice29.txt.zst-16 27712 43447 ns/op 3500.58 MB/s 99 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/html_x_4.zst-16 62826 18750 ns/op 21845.10 MB/s 104 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/paper-100k.pdf.zst-16 631545 1794 ns/op 57078.74 MB/s 2 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/fireworks.jpeg.zst-16 1690140 712 ns/op 172938.13 MB/s 1 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/urls.10K.zst-16 10432 113593 ns/op 6180.73 MB/s 1143 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/html.zst-16 113206 10671 ns/op 9596.27 MB/s 15 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/comp-data.bin.zst-16 1530615 779 ns/op 5229.49 MB/s 0 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/kppkn.gtb.zst-16 65217 16192 ns/op 11383.34 MB/s 46 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/geo.protodata.zst-16 292671 4039 ns/op 29363.19 MB/s 6 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/plrabn12.txt.zst-16 26314 46021 ns/op 10470.43 MB/s 293 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/lcet10.txt.zst-16 33897 34900 ns/op 12227.96 MB/s 205 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/asyoulik.txt.zst-16 104348 11433 ns/op 10949.01 MB/s 20 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/alice29.txt.zst-16 75949 15510 ns/op 9805.60 MB/s 32 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/html_x_4.zst-16 173910 6756 ns/op 60624.29 MB/s 37 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/paper-100k.pdf.zst-16 923076 1339 ns/op 76474.87 MB/s 1 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/fireworks.jpeg.zst-16 922920 1351 ns/op 91102.57 MB/s 2 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/urls.10K.zst-16 27649 43618 ns/op 16096.19 MB/s 407 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/html.zst-16 279073 4160 ns/op 24614.18 MB/s 6 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallelCgo/comp-data.bin.zst-16 749938 1579 ns/op 2581.71 MB/s 0 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/kppkn.gtb.zst-32 67356 17857 ns/op 10321.96 MB/s 22.48 pct 102 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/geo.protodata.zst-32 266656 4421 ns/op 26823.21 MB/s 11.89 pct 19 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/plrabn12.txt.zst-32 20992 56842 ns/op 8477.17 MB/s 39.90 pct 754 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/lcet10.txt.zst-32 27456 43932 ns/op 9714.01 MB/s 33.27 pct 524 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/asyoulik.txt.zst-32 78432 15047 ns/op 8319.15 MB/s 40.34 pct 66 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/alice29.txt.zst-32 65800 18436 ns/op 8249.63 MB/s 37.75 pct 88 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/html_x_4.zst-32 102993 11523 ns/op 35546.09 MB/s 3.637 pct 143 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/paper-100k.pdf.zst-32 1000000 1070 ns/op 95720.98 MB/s 80.53 pct 3 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/fireworks.jpeg.zst-32 749802 1752 ns/op 70272.35 MB/s 100.0 pct 5 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/urls.10K.zst-32 22640 52934 ns/op 13263.37 MB/s 26.25 pct 1014 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/html.zst-32 226412 5232 ns/op 19572.27 MB/s 14.49 pct 20 B/op 0 allocs/op
BenchmarkDecoder_DecodeAllParallel/comp-data.bin.zst-32 923041 1276 ns/op 3194.71 MB/s 31.26 pct 0 B/op 0 allocs/op
```
This reflects the performance around May 2020, but this may be out of date.
This reflects the performance around May 2022, but this may be out of date.
## Zstd inside ZIP files

View File

@ -63,13 +63,6 @@ func (b *bitReader) get32BitsFast(n uint8) uint32 {
return v
}
func (b *bitReader) get16BitsFast(n uint8) uint16 {
const regMask = 64 - 1
v := uint16((b.value << (b.bitsRead & regMask)) >> ((regMask + 1 - n) & regMask))
b.bitsRead += n
return v
}
// fillFast() will make sure at least 32 bits are available.
// There must be at least 4 bytes available.
func (b *bitReader) fillFast() {

View File

@ -5,8 +5,6 @@
package zstd
import "fmt"
// bitWriter will write bits.
// First bit will be LSB of the first byte of output.
type bitWriter struct {
@ -73,80 +71,6 @@ func (b *bitWriter) addBits16Clean(value uint16, bits uint8) {
b.nBits += bits
}
// flush will flush all pending full bytes.
// There will be at least 56 bits available for writing when this has been called.
// Using flush32 is faster, but leaves less space for writing.
func (b *bitWriter) flush() {
v := b.nBits >> 3
switch v {
case 0:
case 1:
b.out = append(b.out,
byte(b.bitContainer),
)
case 2:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
)
case 3:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
)
case 4:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
)
case 5:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
)
case 6:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
byte(b.bitContainer>>40),
)
case 7:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
byte(b.bitContainer>>40),
byte(b.bitContainer>>48),
)
case 8:
b.out = append(b.out,
byte(b.bitContainer),
byte(b.bitContainer>>8),
byte(b.bitContainer>>16),
byte(b.bitContainer>>24),
byte(b.bitContainer>>32),
byte(b.bitContainer>>40),
byte(b.bitContainer>>48),
byte(b.bitContainer>>56),
)
default:
panic(fmt.Errorf("bits (%d) > 64", b.nBits))
}
b.bitContainer >>= v << 3
b.nBits &= 7
}
// flush32 will flush out, so there are at least 32 bits available for writing.
func (b *bitWriter) flush32() {
if b.nBits < 32 {

View File

@ -5,9 +5,14 @@
package zstd
import (
"bytes"
"encoding/binary"
"errors"
"fmt"
"io"
"io/ioutil"
"os"
"path/filepath"
"sync"
"github.com/klauspost/compress/huff0"
@ -38,14 +43,14 @@ const (
// maxCompressedBlockSize is the biggest allowed compressed block size (128KB)
maxCompressedBlockSize = 128 << 10
compressedBlockOverAlloc = 16
maxCompressedBlockSizeAlloc = 128<<10 + compressedBlockOverAlloc
// Maximum possible block size (all Raw+Uncompressed).
maxBlockSize = (1 << 21) - 1
// https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#literals_section_header
maxCompressedLiteralSize = 1 << 18
maxRLELiteralSize = 1 << 20
maxMatchLen = 131074
maxSequences = 0x7f00 + 0xffff
maxMatchLen = 131074
maxSequences = 0x7f00 + 0xffff
// We support slightly less than the reference decoder to be able to
// use ints on 32 bit archs.
@ -97,7 +102,6 @@ type blockDec struct {
// Block is RLE, this is the size.
RLESize uint32
tmp [4]byte
Type blockType
@ -136,7 +140,7 @@ func (b *blockDec) reset(br byteBuffer, windowSize uint64) error {
b.Type = blockType((bh >> 1) & 3)
// find size.
cSize := int(bh >> 3)
maxSize := maxBlockSize
maxSize := maxCompressedBlockSizeAlloc
switch b.Type {
case blockTypeReserved:
return ErrReservedBlockType
@ -157,9 +161,9 @@ func (b *blockDec) reset(br byteBuffer, windowSize uint64) error {
println("Data size on stream:", cSize)
}
b.RLESize = 0
maxSize = maxCompressedBlockSize
maxSize = maxCompressedBlockSizeAlloc
if windowSize < maxCompressedBlockSize && b.lowMem {
maxSize = int(windowSize)
maxSize = int(windowSize) + compressedBlockOverAlloc
}
if cSize > maxCompressedBlockSize || uint64(cSize) > b.WindowSize {
if debugDecoder {
@ -190,9 +194,9 @@ func (b *blockDec) reset(br byteBuffer, windowSize uint64) error {
// Read block data.
if cap(b.dataStorage) < cSize {
if b.lowMem || cSize > maxCompressedBlockSize {
b.dataStorage = make([]byte, 0, cSize)
b.dataStorage = make([]byte, 0, cSize+compressedBlockOverAlloc)
} else {
b.dataStorage = make([]byte, 0, maxCompressedBlockSize)
b.dataStorage = make([]byte, 0, maxCompressedBlockSizeAlloc)
}
}
if cap(b.dst) <= maxSize {
@ -360,14 +364,9 @@ func (b *blockDec) decodeLiterals(in []byte, hist *history) (remain []byte, err
}
if cap(b.literalBuf) < litRegenSize {
if b.lowMem {
b.literalBuf = make([]byte, litRegenSize)
b.literalBuf = make([]byte, litRegenSize, litRegenSize+compressedBlockOverAlloc)
} else {
if litRegenSize > maxCompressedLiteralSize {
// Exceptional
b.literalBuf = make([]byte, litRegenSize)
} else {
b.literalBuf = make([]byte, litRegenSize, maxCompressedLiteralSize)
}
b.literalBuf = make([]byte, litRegenSize, maxCompressedBlockSize+compressedBlockOverAlloc)
}
}
literals = b.literalBuf[:litRegenSize]
@ -397,14 +396,14 @@ func (b *blockDec) decodeLiterals(in []byte, hist *history) (remain []byte, err
// Ensure we have space to store it.
if cap(b.literalBuf) < litRegenSize {
if b.lowMem {
b.literalBuf = make([]byte, 0, litRegenSize)
b.literalBuf = make([]byte, 0, litRegenSize+compressedBlockOverAlloc)
} else {
b.literalBuf = make([]byte, 0, maxCompressedLiteralSize)
b.literalBuf = make([]byte, 0, maxCompressedBlockSize+compressedBlockOverAlloc)
}
}
var err error
// Use our out buffer.
huff.MaxDecodedSize = maxCompressedBlockSize
huff.MaxDecodedSize = litRegenSize
if fourStreams {
literals, err = huff.Decoder().Decompress4X(b.literalBuf[:0:litRegenSize], literals)
} else {
@ -429,9 +428,9 @@ func (b *blockDec) decodeLiterals(in []byte, hist *history) (remain []byte, err
// Ensure we have space to store it.
if cap(b.literalBuf) < litRegenSize {
if b.lowMem {
b.literalBuf = make([]byte, 0, litRegenSize)
b.literalBuf = make([]byte, 0, litRegenSize+compressedBlockOverAlloc)
} else {
b.literalBuf = make([]byte, 0, maxCompressedBlockSize)
b.literalBuf = make([]byte, 0, maxCompressedBlockSize+compressedBlockOverAlloc)
}
}
huff := hist.huffTree
@ -448,7 +447,7 @@ func (b *blockDec) decodeLiterals(in []byte, hist *history) (remain []byte, err
return in, err
}
hist.huffTree = huff
huff.MaxDecodedSize = maxCompressedBlockSize
huff.MaxDecodedSize = litRegenSize
// Use our out buffer.
if fourStreams {
literals, err = huff.Decoder().Decompress4X(b.literalBuf[:0:litRegenSize], literals)
@ -463,6 +462,8 @@ func (b *blockDec) decodeLiterals(in []byte, hist *history) (remain []byte, err
if len(literals) != litRegenSize {
return in, fmt.Errorf("literal output size mismatch want %d, got %d", litRegenSize, len(literals))
}
// Re-cap to get extra size.
literals = b.literalBuf[:len(literals)]
if debugDecoder {
printf("Decompressed %d literals into %d bytes\n", litCompSize, litRegenSize)
}
@ -486,10 +487,15 @@ func (b *blockDec) decodeCompressed(hist *history) error {
b.dst = append(b.dst, hist.decoders.literals...)
return nil
}
err = hist.decoders.decodeSync(hist)
before := len(hist.decoders.out)
err = hist.decoders.decodeSync(hist.b[hist.ignoreBuffer:])
if err != nil {
return err
}
if hist.decoders.maxSyncLen > 0 {
hist.decoders.maxSyncLen += uint64(before)
hist.decoders.maxSyncLen -= uint64(len(hist.decoders.out))
}
b.dst = hist.decoders.out
hist.recentOffsets = hist.decoders.prevOffset
return nil
@ -632,6 +638,22 @@ func (b *blockDec) prepareSequences(in []byte, hist *history) (err error) {
println("initializing sequences:", err)
return err
}
// Extract blocks...
if false && hist.dict == nil {
fatalErr := func(err error) {
if err != nil {
panic(err)
}
}
fn := fmt.Sprintf("n-%d-lits-%d-prev-%d-%d-%d-win-%d.blk", hist.decoders.nSeqs, len(hist.decoders.literals), hist.recentOffsets[0], hist.recentOffsets[1], hist.recentOffsets[2], hist.windowSize)
var buf bytes.Buffer
fatalErr(binary.Write(&buf, binary.LittleEndian, hist.decoders.litLengths.fse))
fatalErr(binary.Write(&buf, binary.LittleEndian, hist.decoders.matchLengths.fse))
fatalErr(binary.Write(&buf, binary.LittleEndian, hist.decoders.offsets.fse))
buf.Write(in)
ioutil.WriteFile(filepath.Join("testdata", "seqs", fn), buf.Bytes(), os.ModePerm)
}
return nil
}
@ -650,6 +672,7 @@ func (b *blockDec) decodeSequences(hist *history) error {
}
hist.decoders.windowSize = hist.windowSize
hist.decoders.prevOffset = hist.recentOffsets
err := hist.decoders.decode(b.sequence)
hist.recentOffsets = hist.decoders.prevOffset
return err

View File

@ -23,7 +23,7 @@ type byteBuffer interface {
readByte() (byte, error)
// Skip n bytes.
skipN(n int) error
skipN(n int64) error
}
// in-memory buffer
@ -52,10 +52,6 @@ func (b *byteBuf) readBig(n int, dst []byte) ([]byte, error) {
return r, nil
}
func (b *byteBuf) remain() []byte {
return *b
}
func (b *byteBuf) readByte() (byte, error) {
bb := *b
if len(bb) < 1 {
@ -66,9 +62,12 @@ func (b *byteBuf) readByte() (byte, error) {
return r, nil
}
func (b *byteBuf) skipN(n int) error {
func (b *byteBuf) skipN(n int64) error {
bb := *b
if len(bb) < n {
if n < 0 {
return fmt.Errorf("negative skip (%d) requested", n)
}
if int64(len(bb)) < n {
return io.ErrUnexpectedEOF
}
*b = bb[n:]
@ -124,9 +123,9 @@ func (r *readerWrapper) readByte() (byte, error) {
return r.tmp[0], nil
}
func (r *readerWrapper) skipN(n int) error {
n2, err := io.CopyN(ioutil.Discard, r.r, int64(n))
if n2 != int64(n) {
func (r *readerWrapper) skipN(n int64) error {
n2, err := io.CopyN(ioutil.Discard, r.r, n)
if n2 != n {
err = io.ErrUnexpectedEOF
}
return err

View File

@ -13,12 +13,6 @@ type byteReader struct {
off int
}
// init will initialize the reader and set the input.
func (b *byteReader) init(in []byte) {
b.b = in
b.off = 0
}
// advance the stream b n bytes.
func (b *byteReader) advance(n uint) {
b.off += int(n)

View File

@ -347,18 +347,23 @@ func (d *Decoder) DecodeAll(input, dst []byte) ([]byte, error) {
}
frame.history.setDict(&dict)
}
if frame.FrameContentSize != fcsUnknown && frame.FrameContentSize > d.o.maxDecodedSize-uint64(len(dst)) {
return dst, ErrDecoderSizeExceeded
if frame.WindowSize > d.o.maxWindowSize {
if debugDecoder {
println("window size exceeded:", frame.WindowSize, ">", d.o.maxWindowSize)
}
return dst, ErrWindowSizeExceeded
}
if frame.FrameContentSize < 1<<30 {
// Never preallocate more than 1 GB up front.
if frame.FrameContentSize != fcsUnknown {
if frame.FrameContentSize > d.o.maxDecodedSize-uint64(len(dst)) {
return dst, ErrDecoderSizeExceeded
}
if cap(dst)-len(dst) < int(frame.FrameContentSize) {
dst2 := make([]byte, len(dst), len(dst)+int(frame.FrameContentSize))
dst2 := make([]byte, len(dst), len(dst)+int(frame.FrameContentSize)+compressedBlockOverAlloc)
copy(dst2, dst)
dst = dst2
}
}
if cap(dst) == 0 {
// Allocate len(input) * 2 by default if nothing is provided
// and we didn't get frame content size.
@ -437,7 +442,7 @@ func (d *Decoder) nextBlock(blocking bool) (ok bool) {
println("got", len(d.current.b), "bytes, error:", d.current.err, "data crc:", tmp)
}
if len(next.b) > 0 {
if !d.o.ignoreChecksum && len(next.b) > 0 {
n, err := d.current.crc.Write(next.b)
if err == nil {
if n != len(next.b) {
@ -449,7 +454,7 @@ func (d *Decoder) nextBlock(blocking bool) (ok bool) {
got := d.current.crc.Sum64()
var tmp [4]byte
binary.LittleEndian.PutUint32(tmp[:], uint32(got))
if !bytes.Equal(tmp[:], next.d.checkCRC) && !ignoreCRC {
if !d.o.ignoreChecksum && !bytes.Equal(tmp[:], next.d.checkCRC) {
if debugDecoder {
println("CRC Check Failed:", tmp[:], " (got) !=", next.d.checkCRC, "(on stream)")
}
@ -533,9 +538,15 @@ func (d *Decoder) nextBlockSync() (ok bool) {
// Update/Check CRC
if d.frame.HasCheckSum {
d.frame.crc.Write(d.current.b)
if !d.o.ignoreChecksum {
d.frame.crc.Write(d.current.b)
}
if d.current.d.Last {
d.current.err = d.frame.checkCRC()
if !d.o.ignoreChecksum {
d.current.err = d.frame.checkCRC()
} else {
d.current.err = d.frame.consumeCRC()
}
if d.current.err != nil {
println("CRC error:", d.current.err)
return false
@ -629,60 +640,18 @@ func (d *Decoder) startSyncDecoder(r io.Reader) error {
// Create Decoder:
// ASYNC:
// Spawn 4 go routines.
// 0: Read frames and decode blocks.
// 1: Decode block and literals. Receives hufftree and seqdecs, returns seqdecs and huff tree.
// 2: Wait for recentOffsets if needed. Decode sequences, send recentOffsets.
// 3: Wait for stream history, execute sequences, send stream history.
// Spawn 3 go routines.
// 0: Read frames and decode block literals.
// 1: Decode sequences.
// 2: Execute sequences, send to output.
func (d *Decoder) startStreamDecoder(ctx context.Context, r io.Reader, output chan decodeOutput) {
defer d.streamWg.Done()
br := readerWrapper{r: r}
var seqPrepare = make(chan *blockDec, d.o.concurrent)
var seqDecode = make(chan *blockDec, d.o.concurrent)
var seqExecute = make(chan *blockDec, d.o.concurrent)
// Async 1: Prepare blocks...
go func() {
var hist history
var hasErr bool
for block := range seqPrepare {
if hasErr {
if block != nil {
seqDecode <- block
}
continue
}
if block.async.newHist != nil {
if debugDecoder {
println("Async 1: new history")
}
hist.reset()
if block.async.newHist.dict != nil {
hist.setDict(block.async.newHist.dict)
}
}
if block.err != nil || block.Type != blockTypeCompressed {
hasErr = block.err != nil
seqDecode <- block
continue
}
remain, err := block.decodeLiterals(block.data, &hist)
block.err = err
hasErr = block.err != nil
if err == nil {
block.async.literals = hist.decoders.literals
block.async.seqData = remain
} else if debugDecoder {
println("decodeLiterals error:", err)
}
seqDecode <- block
}
close(seqDecode)
}()
// Async 2: Decode sequences...
// Async 1: Decode sequences...
go func() {
var hist history
var hasErr bool
@ -696,7 +665,7 @@ func (d *Decoder) startStreamDecoder(ctx context.Context, r io.Reader, output ch
}
if block.async.newHist != nil {
if debugDecoder {
println("Async 2: new history, recent:", block.async.newHist.recentOffsets)
println("Async 1: new history, recent:", block.async.newHist.recentOffsets)
}
hist.decoders = block.async.newHist.decoders
hist.recentOffsets = block.async.newHist.recentOffsets
@ -750,7 +719,7 @@ func (d *Decoder) startStreamDecoder(ctx context.Context, r io.Reader, output ch
}
if block.async.newHist != nil {
if debugDecoder {
println("Async 3: new history")
println("Async 2: new history")
}
hist.windowSize = block.async.newHist.windowSize
hist.allocFrameBuffer = block.async.newHist.allocFrameBuffer
@ -837,6 +806,33 @@ func (d *Decoder) startStreamDecoder(ctx context.Context, r io.Reader, output ch
decodeStream:
for {
var hist history
var hasErr bool
decodeBlock := func(block *blockDec) {
if hasErr {
if block != nil {
seqDecode <- block
}
return
}
if block.err != nil || block.Type != blockTypeCompressed {
hasErr = block.err != nil
seqDecode <- block
return
}
remain, err := block.decodeLiterals(block.data, &hist)
block.err = err
hasErr = block.err != nil
if err == nil {
block.async.literals = hist.decoders.literals
block.async.seqData = remain
} else if debugDecoder {
println("decodeLiterals error:", err)
}
seqDecode <- block
}
frame := d.frame
if debugDecoder {
println("New frame...")
@ -863,7 +859,7 @@ decodeStream:
case <-ctx.Done():
case dec := <-d.decoders:
dec.sendErr(err)
seqPrepare <- dec
decodeBlock(dec)
}
break decodeStream
}
@ -883,6 +879,10 @@ decodeStream:
if debugDecoder {
println("Alloc History:", h.allocFrameBuffer)
}
hist.reset()
if h.dict != nil {
hist.setDict(h.dict)
}
dec.async.newHist = &h
dec.async.fcs = frame.FrameContentSize
historySent = true
@ -909,7 +909,7 @@ decodeStream:
}
err = dec.err
last := dec.Last
seqPrepare <- dec
decodeBlock(dec)
if err != nil {
break decodeStream
}
@ -918,7 +918,7 @@ decodeStream:
}
}
}
close(seqPrepare)
close(seqDecode)
wg.Wait()
d.frame.history.b = frameHistCache
}

View File

@ -19,6 +19,7 @@ type decoderOptions struct {
maxDecodedSize uint64
maxWindowSize uint64
dicts []dict
ignoreChecksum bool
}
func (o *decoderOptions) setDefault() {
@ -31,7 +32,7 @@ func (o *decoderOptions) setDefault() {
if o.concurrent > 4 {
o.concurrent = 4
}
o.maxDecodedSize = 1 << 63
o.maxDecodedSize = 64 << 30
}
// WithDecoderLowmem will set whether to use a lower amount of memory,
@ -66,7 +67,7 @@ func WithDecoderConcurrency(n int) DOption {
// WithDecoderMaxMemory allows to set a maximum decoded size for in-memory
// non-streaming operations or maximum window size for streaming operations.
// This can be used to control memory usage of potentially hostile content.
// Maximum and default is 1 << 63 bytes.
// Maximum is 1 << 63 bytes. Default is 64GiB.
func WithDecoderMaxMemory(n uint64) DOption {
return func(o *decoderOptions) error {
if n == 0 {
@ -112,3 +113,11 @@ func WithDecoderMaxWindow(size uint64) DOption {
return nil
}
}
// IgnoreChecksum allows to forcibly ignore checksum checking.
func IgnoreChecksum(b bool) DOption {
return func(o *decoderOptions) error {
o.ignoreChecksum = b
return nil
}
}

View File

@ -156,8 +156,8 @@ encodeLoop:
panic("offset0 was 0")
}
nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
nextHashL := hashLen(cv, betterLongTableBits, betterLongLen)
nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
candidateL := e.longTable[nextHashL]
candidateS := e.table[nextHashS]
@ -518,8 +518,8 @@ encodeLoop:
}
// Store this, since we have it.
nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
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
@ -674,8 +674,8 @@ encodeLoop:
panic("offset0 was 0")
}
nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
nextHashL := hashLen(cv, betterLongTableBits, betterLongLen)
nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
candidateL := e.longTable[nextHashL]
candidateS := e.table[nextHashS]
@ -1047,8 +1047,8 @@ encodeLoop:
}
// Store this, since we have it.
nextHashS := hashLen(cv, betterShortTableBits, betterShortLen)
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

View File

@ -127,8 +127,8 @@ encodeLoop:
panic("offset0 was 0")
}
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
candidateL := e.longTable[nextHashL]
candidateS := e.table[nextHashS]
@ -439,8 +439,8 @@ encodeLoop:
var t int32
for {
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
candidateL := e.longTable[nextHashL]
candidateS := e.table[nextHashS]
@ -785,8 +785,8 @@ encodeLoop:
panic("offset0 was 0")
}
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
candidateL := e.longTable[nextHashL]
candidateS := e.table[nextHashS]
@ -969,7 +969,7 @@ encodeLoop:
te0 := tableEntry{offset: index0 + e.cur, val: uint32(cv0)}
te1 := tableEntry{offset: index1 + e.cur, val: uint32(cv1)}
longHash1 := hashLen(cv0, dFastLongTableBits, dFastLongLen)
longHash2 := hashLen(cv0, dFastLongTableBits, dFastLongLen)
longHash2 := hashLen(cv1, dFastLongTableBits, dFastLongLen)
e.longTable[longHash1] = te0
e.longTable[longHash2] = te1
e.markLongShardDirty(longHash1)
@ -1002,8 +1002,8 @@ encodeLoop:
}
// Store this, since we have it.
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
nextHashL := hashLen(cv, dFastLongTableBits, dFastLongLen)
nextHashS := hashLen(cv, dFastShortTableBits, dFastShortLen)
// We have at least 4 byte match.
// No need to check backwards. We come straight from a match

View File

@ -528,8 +528,8 @@ func (e *Encoder) EncodeAll(src, dst []byte) []byte {
// If a non-single block is needed the encoder will reset again.
e.encoders <- enc
}()
// Use single segments when above minimum window and below 1MB.
single := len(src) < 1<<20 && len(src) > MinWindowSize
// Use single segments when above minimum window and below window size.
single := len(src) <= e.o.windowSize && len(src) > MinWindowSize
if e.o.single != nil {
single = *e.o.single
}
@ -551,7 +551,7 @@ func (e *Encoder) EncodeAll(src, dst []byte) []byte {
}
// If we can do everything in one block, prefer that.
if len(src) <= maxCompressedBlockSize {
if len(src) <= e.o.blockSize {
enc.Reset(e.o.dict, true)
// Slightly faster with no history and everything in one block.
if e.o.crc {

View File

@ -283,7 +283,7 @@ func WithNoEntropyCompression(b bool) EOption {
// a decoder is allowed to reject a compressed frame which requests a memory size beyond decoder's authorized range.
// For broader compatibility, decoders are recommended to support memory sizes of at least 8 MB.
// This is only a recommendation, each decoder is free to support higher or lower limits, depending on local limitations.
// If this is not specified, block encodes will automatically choose this based on the input size.
// If this is not specified, block encodes will automatically choose this based on the input size and the window size.
// This setting has no effect on streamed encodes.
func WithSingleSegment(b bool) EOption {
return func(o *encoderOptions) error {

View File

@ -106,7 +106,7 @@ func (d *frameDec) reset(br byteBuffer) error {
}
n := uint32(b[0]) | (uint32(b[1]) << 8) | (uint32(b[2]) << 16) | (uint32(b[3]) << 24)
println("Skipping frame with", n, "bytes.")
err = br.skipN(int(n))
err = br.skipN(int64(n))
if err != nil {
if debugDecoder {
println("Reading discarded frame", err)
@ -231,20 +231,27 @@ func (d *frameDec) reset(br byteBuffer) error {
d.crc.Reset()
}
if d.WindowSize > d.o.maxWindowSize {
if debugDecoder {
printf("window size %d > max %d\n", d.WindowSize, d.o.maxWindowSize)
}
return ErrWindowSizeExceeded
}
if d.WindowSize == 0 && d.SingleSegment {
// We may not need window in this case.
d.WindowSize = d.FrameContentSize
if d.WindowSize < MinWindowSize {
d.WindowSize = MinWindowSize
}
if d.WindowSize > d.o.maxDecodedSize {
if debugDecoder {
printf("window size %d > max %d\n", d.WindowSize, d.o.maxWindowSize)
}
return ErrDecoderSizeExceeded
}
}
if d.WindowSize > uint64(d.o.maxWindowSize) {
if debugDecoder {
printf("window size %d > max %d\n", d.WindowSize, d.o.maxWindowSize)
}
return ErrWindowSizeExceeded
}
// The minimum Window_Size is 1 KB.
if d.WindowSize < MinWindowSize {
if debugDecoder {
@ -253,10 +260,11 @@ func (d *frameDec) reset(br byteBuffer) error {
return ErrWindowSizeTooSmall
}
d.history.windowSize = int(d.WindowSize)
if d.o.lowMem && d.history.windowSize < maxBlockSize {
if !d.o.lowMem || d.history.windowSize < maxBlockSize {
// Alloc 2x window size if not low-mem, or very small window size.
d.history.allocFrameBuffer = d.history.windowSize * 2
// TODO: Maybe use FrameContent size
} else {
// Alloc with one additional block
d.history.allocFrameBuffer = d.history.windowSize + maxBlockSize
}
@ -290,13 +298,6 @@ func (d *frameDec) checkCRC() error {
if !d.HasCheckSum {
return nil
}
var tmp [4]byte
got := d.crc.Sum64()
// Flip to match file order.
tmp[0] = byte(got >> 0)
tmp[1] = byte(got >> 8)
tmp[2] = byte(got >> 16)
tmp[3] = byte(got >> 24)
// We can overwrite upper tmp now
want, err := d.rawInput.readSmall(4)
@ -305,7 +306,19 @@ func (d *frameDec) checkCRC() error {
return err
}
if !bytes.Equal(tmp[:], want) && !ignoreCRC {
if d.o.ignoreChecksum {
return nil
}
var tmp [4]byte
got := d.crc.Sum64()
// Flip to match file order.
tmp[0] = byte(got >> 0)
tmp[1] = byte(got >> 8)
tmp[2] = byte(got >> 16)
tmp[3] = byte(got >> 24)
if !bytes.Equal(tmp[:], want) {
if debugDecoder {
println("CRC Check Failed:", tmp[:], "!=", want)
}
@ -317,6 +330,19 @@ func (d *frameDec) checkCRC() error {
return nil
}
// consumeCRC reads the checksum data if the frame has one.
func (d *frameDec) consumeCRC() error {
if d.HasCheckSum {
_, err := d.rawInput.readSmall(4)
if err != nil {
println("CRC missing?", err)
return err
}
}
return nil
}
// runDecoder will create a sync decoder that will decode a block of data.
func (d *frameDec) runDecoder(dst []byte, dec *blockDec) ([]byte, error) {
saved := d.history.b
@ -326,6 +352,19 @@ func (d *frameDec) runDecoder(dst []byte, dec *blockDec) ([]byte, error) {
d.history.ignoreBuffer = len(dst)
// Store input length, so we only check new data.
crcStart := len(dst)
d.history.decoders.maxSyncLen = 0
if d.FrameContentSize != fcsUnknown {
d.history.decoders.maxSyncLen = d.FrameContentSize + uint64(len(dst))
if d.history.decoders.maxSyncLen > d.o.maxDecodedSize {
return dst, ErrDecoderSizeExceeded
}
if uint64(cap(dst)) < d.history.decoders.maxSyncLen {
// Alloc for output
dst2 := make([]byte, len(dst), d.history.decoders.maxSyncLen+compressedBlockOverAlloc)
copy(dst2, dst)
dst = dst2
}
}
var err error
for {
err = dec.reset(d.rawInput, d.WindowSize)
@ -360,13 +399,17 @@ func (d *frameDec) runDecoder(dst []byte, dec *blockDec) ([]byte, error) {
if d.FrameContentSize != fcsUnknown && uint64(len(d.history.b)-crcStart) != d.FrameContentSize {
err = ErrFrameSizeMismatch
} else if d.HasCheckSum {
var n int
n, err = d.crc.Write(dst[crcStart:])
if err == nil {
if n != len(dst)-crcStart {
err = io.ErrShortWrite
} else {
err = d.checkCRC()
if d.o.ignoreChecksum {
err = d.consumeCRC()
} else {
var n int
n, err = d.crc.Write(dst[crcStart:])
if err == nil {
if n != len(dst)-crcStart {
err = io.ErrShortWrite
} else {
err = d.checkCRC()
}
}
}
}

View File

@ -5,8 +5,10 @@
package zstd
import (
"encoding/binary"
"errors"
"fmt"
"io"
)
const (
@ -178,10 +180,32 @@ func (s *fseDecoder) readNCount(b *byteReader, maxSymbol uint16) error {
return fmt.Errorf("corruption detected (total %d != %d)", gotTotal, 1<<s.actualTableLog)
}
b.advance((bitCount + 7) >> 3)
// println(s.norm[:s.symbolLen], s.symbolLen)
return s.buildDtable()
}
func (s *fseDecoder) mustReadFrom(r io.Reader) {
fatalErr := func(err error) {
if err != nil {
panic(err)
}
}
// dt [maxTablesize]decSymbol // Decompression table.
// symbolLen uint16 // Length of active part of the symbol table.
// actualTableLog uint8 // Selected tablelog.
// maxBits uint8 // Maximum number of additional bits
// // used for table creation to avoid allocations.
// stateTable [256]uint16
// norm [maxSymbolValue + 1]int16
// preDefined bool
fatalErr(binary.Read(r, binary.LittleEndian, &s.dt))
fatalErr(binary.Read(r, binary.LittleEndian, &s.symbolLen))
fatalErr(binary.Read(r, binary.LittleEndian, &s.actualTableLog))
fatalErr(binary.Read(r, binary.LittleEndian, &s.maxBits))
fatalErr(binary.Read(r, binary.LittleEndian, &s.stateTable))
fatalErr(binary.Read(r, binary.LittleEndian, &s.norm))
fatalErr(binary.Read(r, binary.LittleEndian, &s.preDefined))
}
// decSymbol contains information about a state entry,
// Including the state offset base, the output symbol and
// the number of bits to read for the low part of the destination state.
@ -204,18 +228,10 @@ func (d decSymbol) newState() uint16 {
return uint16(d >> 16)
}
func (d decSymbol) baseline() uint32 {
return uint32(d >> 32)
}
func (d decSymbol) baselineInt() int {
return int(d >> 32)
}
func (d *decSymbol) set(nbits, addBits uint8, newState uint16, baseline uint32) {
*d = decSymbol(nbits) | (decSymbol(addBits) << 8) | (decSymbol(newState) << 16) | (decSymbol(baseline) << 32)
}
func (d *decSymbol) setNBits(nBits uint8) {
const mask = 0xffffffffffffff00
*d = (*d & mask) | decSymbol(nBits)
@ -231,11 +247,6 @@ func (d *decSymbol) setNewState(state uint16) {
*d = (*d & mask) | decSymbol(state)<<16
}
func (d *decSymbol) setBaseline(baseline uint32) {
const mask = 0xffffffff
*d = (*d & mask) | decSymbol(baseline)<<32
}
func (d *decSymbol) setExt(addBits uint8, baseline uint32) {
const mask = 0xffff00ff
*d = (*d & mask) | (decSymbol(addBits) << 8) | (decSymbol(baseline) << 32)
@ -257,68 +268,6 @@ func (s *fseDecoder) setRLE(symbol decSymbol) {
s.dt[0] = symbol
}
// buildDtable will build the decoding table.
func (s *fseDecoder) buildDtable() error {
tableSize := uint32(1 << s.actualTableLog)
highThreshold := tableSize - 1
symbolNext := s.stateTable[:256]
// Init, lay down lowprob symbols
{
for i, v := range s.norm[:s.symbolLen] {
if v == -1 {
s.dt[highThreshold].setAddBits(uint8(i))
highThreshold--
symbolNext[i] = 1
} else {
symbolNext[i] = uint16(v)
}
}
}
// Spread symbols
{
tableMask := tableSize - 1
step := tableStep(tableSize)
position := uint32(0)
for ss, v := range s.norm[:s.symbolLen] {
for i := 0; i < int(v); i++ {
s.dt[position].setAddBits(uint8(ss))
position = (position + step) & tableMask
for position > highThreshold {
// lowprob area
position = (position + step) & tableMask
}
}
}
if position != 0 {
// position must reach all cells once, otherwise normalizedCounter is incorrect
return errors.New("corrupted input (position != 0)")
}
}
// Build Decoding table
{
tableSize := uint16(1 << s.actualTableLog)
for u, v := range s.dt[:tableSize] {
symbol := v.addBits()
nextState := symbolNext[symbol]
symbolNext[symbol] = nextState + 1
nBits := s.actualTableLog - byte(highBits(uint32(nextState)))
s.dt[u&maxTableMask].setNBits(nBits)
newState := (nextState << nBits) - tableSize
if newState > tableSize {
return fmt.Errorf("newState (%d) outside table size (%d)", newState, tableSize)
}
if newState == uint16(u) && nBits == 0 {
// Seems weird that this is possible with nbits > 0.
return fmt.Errorf("newState (%d) == oldState (%d) and no bits", newState, u)
}
s.dt[u&maxTableMask].setNewState(newState)
}
}
return nil
}
// transform will transform the decoder table into a table usable for
// decoding without having to apply the transformation while decoding.
// The state will contain the base value and the number of bits to read.
@ -352,34 +301,7 @@ func (s *fseState) init(br *bitReader, tableLog uint8, dt []decSymbol) {
s.state = dt[br.getBits(tableLog)]
}
// next returns the current symbol and sets the next state.
// At least tablelog bits must be available in the bit reader.
func (s *fseState) next(br *bitReader) {
lowBits := uint16(br.getBits(s.state.nbBits()))
s.state = s.dt[s.state.newState()+lowBits]
}
// finished returns true if all bits have been read from the bitstream
// and the next state would require reading bits from the input.
func (s *fseState) finished(br *bitReader) bool {
return br.finished() && s.state.nbBits() > 0
}
// final returns the current state symbol without decoding the next.
func (s *fseState) final() (int, uint8) {
return s.state.baselineInt(), s.state.addBits()
}
// final returns the current state symbol without decoding the next.
func (s decSymbol) final() (int, uint8) {
return s.baselineInt(), s.addBits()
}
// nextFast returns the next symbol and sets the next state.
// This can only be used if no symbols are 0 bits.
// At least tablelog bits must be available in the bit reader.
func (s *fseState) nextFast(br *bitReader) (uint32, uint8) {
lowBits := br.get16BitsFast(s.state.nbBits())
s.state = s.dt[s.state.newState()+lowBits]
return s.state.baseline(), s.state.addBits()
}

View File

@ -0,0 +1,64 @@
//go:build amd64 && !appengine && !noasm && gc
// +build amd64,!appengine,!noasm,gc
package zstd
import (
"fmt"
)
type buildDtableAsmContext struct {
// inputs
stateTable *uint16
norm *int16
dt *uint64
// outputs --- set by the procedure in the case of error;
// for interpretation please see the error handling part below
errParam1 uint64
errParam2 uint64
}
// buildDtable_asm is an x86 assembly implementation of fseDecoder.buildDtable.
// Function returns non-zero exit code on error.
// go:noescape
func buildDtable_asm(s *fseDecoder, ctx *buildDtableAsmContext) int
// please keep in sync with _generate/gen_fse.go
const (
errorCorruptedNormalizedCounter = 1
errorNewStateTooBig = 2
errorNewStateNoBits = 3
)
// buildDtable will build the decoding table.
func (s *fseDecoder) buildDtable() error {
ctx := buildDtableAsmContext{
stateTable: &s.stateTable[0],
norm: &s.norm[0],
dt: (*uint64)(&s.dt[0]),
}
code := buildDtable_asm(s, &ctx)
if code != 0 {
switch code {
case errorCorruptedNormalizedCounter:
position := ctx.errParam1
return fmt.Errorf("corrupted input (position=%d, expected 0)", position)
case errorNewStateTooBig:
newState := decSymbol(ctx.errParam1)
size := ctx.errParam2
return fmt.Errorf("newState (%d) outside table size (%d)", newState, size)
case errorNewStateNoBits:
newState := decSymbol(ctx.errParam1)
oldState := decSymbol(ctx.errParam2)
return fmt.Errorf("newState (%d) == oldState (%d) and no bits", newState, oldState)
default:
return fmt.Errorf("buildDtable_asm returned unhandled nonzero code = %d", code)
}
}
return nil
}

View File

@ -0,0 +1,127 @@
// Code generated by command: go run gen_fse.go -out ../fse_decoder_amd64.s -pkg=zstd. DO NOT EDIT.
//go:build !appengine && !noasm && gc && !noasm
// +build !appengine,!noasm,gc,!noasm
// func buildDtable_asm(s *fseDecoder, ctx *buildDtableAsmContext) int
TEXT ·buildDtable_asm(SB), $0-24
MOVQ ctx+8(FP), CX
MOVQ s+0(FP), DI
// Load values
MOVBQZX 4098(DI), DX
XORQ AX, AX
BTSQ DX, AX
MOVQ (CX), BX
MOVQ 16(CX), SI
LEAQ -1(AX), R8
MOVQ 8(CX), CX
MOVWQZX 4096(DI), DI
// End load values
// Init, lay down lowprob symbols
XORQ R9, R9
JMP init_main_loop_condition
init_main_loop:
MOVWQSX (CX)(R9*2), R10
CMPW R10, $-1
JNE do_not_update_high_threshold
MOVB R9, 1(SI)(R8*8)
DECQ R8
MOVQ $0x0000000000000001, R10
do_not_update_high_threshold:
MOVW R10, (BX)(R9*2)
INCQ R9
init_main_loop_condition:
CMPQ R9, DI
JL init_main_loop
// Spread symbols
// Calculate table step
MOVQ AX, R9
SHRQ $0x01, R9
MOVQ AX, R10
SHRQ $0x03, R10
LEAQ 3(R9)(R10*1), R9
// Fill add bits values
LEAQ -1(AX), R10
XORQ R11, R11
XORQ R12, R12
JMP spread_main_loop_condition
spread_main_loop:
XORQ R13, R13
MOVWQSX (CX)(R12*2), R14
JMP spread_inner_loop_condition
spread_inner_loop:
MOVB R12, 1(SI)(R11*8)
adjust_position:
ADDQ R9, R11
ANDQ R10, R11
CMPQ R11, R8
JG adjust_position
INCQ R13
spread_inner_loop_condition:
CMPQ R13, R14
JL spread_inner_loop
INCQ R12
spread_main_loop_condition:
CMPQ R12, DI
JL spread_main_loop
TESTQ R11, R11
JZ spread_check_ok
MOVQ ctx+8(FP), AX
MOVQ R11, 24(AX)
MOVQ $+1, ret+16(FP)
RET
spread_check_ok:
// Build Decoding table
XORQ DI, DI
build_table_main_table:
MOVBQZX 1(SI)(DI*8), CX
MOVWQZX (BX)(CX*2), R8
LEAQ 1(R8), R9
MOVW R9, (BX)(CX*2)
MOVQ R8, R9
BSRQ R9, R9
MOVQ DX, CX
SUBQ R9, CX
SHLQ CL, R8
SUBQ AX, R8
MOVB CL, (SI)(DI*8)
MOVW R8, 2(SI)(DI*8)
CMPQ R8, AX
JLE build_table_check1_ok
MOVQ ctx+8(FP), CX
MOVQ R8, 24(CX)
MOVQ AX, 32(CX)
MOVQ $+2, ret+16(FP)
RET
build_table_check1_ok:
TESTB CL, CL
JNZ build_table_check2_ok
CMPW R8, DI
JNE build_table_check2_ok
MOVQ ctx+8(FP), AX
MOVQ R8, 24(AX)
MOVQ DI, 32(AX)
MOVQ $+3, ret+16(FP)
RET
build_table_check2_ok:
INCQ DI
CMPQ DI, AX
JL build_table_main_table
MOVQ $+0, ret+16(FP)
RET

View File

@ -0,0 +1,72 @@
//go:build !amd64 || appengine || !gc || noasm
// +build !amd64 appengine !gc noasm
package zstd
import (
"errors"
"fmt"
)
// buildDtable will build the decoding table.
func (s *fseDecoder) buildDtable() error {
tableSize := uint32(1 << s.actualTableLog)
highThreshold := tableSize - 1
symbolNext := s.stateTable[:256]
// Init, lay down lowprob symbols
{
for i, v := range s.norm[:s.symbolLen] {
if v == -1 {
s.dt[highThreshold].setAddBits(uint8(i))
highThreshold--
symbolNext[i] = 1
} else {
symbolNext[i] = uint16(v)
}
}
}
// Spread symbols
{
tableMask := tableSize - 1
step := tableStep(tableSize)
position := uint32(0)
for ss, v := range s.norm[:s.symbolLen] {
for i := 0; i < int(v); i++ {
s.dt[position].setAddBits(uint8(ss))
position = (position + step) & tableMask
for position > highThreshold {
// lowprob area
position = (position + step) & tableMask
}
}
}
if position != 0 {
// position must reach all cells once, otherwise normalizedCounter is incorrect
return errors.New("corrupted input (position != 0)")
}
}
// Build Decoding table
{
tableSize := uint16(1 << s.actualTableLog)
for u, v := range s.dt[:tableSize] {
symbol := v.addBits()
nextState := symbolNext[symbol]
symbolNext[symbol] = nextState + 1
nBits := s.actualTableLog - byte(highBits(uint32(nextState)))
s.dt[u&maxTableMask].setNBits(nBits)
newState := (nextState << nBits) - tableSize
if newState > tableSize {
return fmt.Errorf("newState (%d) outside table size (%d)", newState, tableSize)
}
if newState == uint16(u) && nBits == 0 {
// Seems weird that this is possible with nbits > 0.
return fmt.Errorf("newState (%d) == oldState (%d) and no bits", newState, u)
}
s.dt[u&maxTableMask].setNewState(newState)
}
}
return nil
}

View File

@ -76,21 +76,6 @@ func (s *fseEncoder) HistogramFinished(maxSymbol uint8, maxCount int) {
s.clearCount = maxCount != 0
}
// prepare will prepare and allocate scratch tables used for both compression and decompression.
func (s *fseEncoder) prepare() (*fseEncoder, error) {
if s == nil {
s = &fseEncoder{}
}
s.useRLE = false
if s.clearCount && s.maxCount == 0 {
for i := range s.count {
s.count[i] = 0
}
s.clearCount = false
}
return s, nil
}
// allocCtable will allocate tables needed for compression.
// If existing tables a re big enough, they are simply re-used.
func (s *fseEncoder) allocCtable() {
@ -709,14 +694,6 @@ func (c *cState) init(bw *bitWriter, ct *cTable, first symbolTransform) {
c.state = c.stateTable[lu]
}
// encode the output symbol provided and write it to the bitstream.
func (c *cState) encode(symbolTT symbolTransform) {
nbBitsOut := (uint32(c.state) + symbolTT.deltaNbBits) >> 16
dstState := int32(c.state>>(nbBitsOut&15)) + int32(symbolTT.deltaFindState)
c.bw.addBits16NC(c.state, uint8(nbBitsOut))
c.state = c.stateTable[dstState]
}
// flush will write the tablelog to the output and flush the remaining full bytes.
func (c *cState) flush(tableLog uint8) {
c.bw.flush32()

View File

@ -1,11 +0,0 @@
//go:build ignorecrc
// +build ignorecrc
// 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
// ignoreCRC can be used for fuzz testing to ignore CRC values...
const ignoreCRC = true

View File

@ -1,11 +0,0 @@
//go:build !ignorecrc
// +build !ignorecrc
// 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
// ignoreCRC can be used for fuzz testing to ignore CRC values...
const ignoreCRC = false

View File

@ -33,9 +33,3 @@ func hashLen(u uint64, length, mls uint8) uint32 {
return (uint32(u) * prime4bytes) >> (32 - length)
}
}
// hash3 returns the hash of the lower 3 bytes of u to fit in a hash table with h bits.
// Preferably h should be a constant and should always be <32.
func hash3(u uint32, h uint8) uint32 {
return ((u << (32 - 24)) * prime3bytes) >> ((32 - h) & 31)
}

View File

@ -73,6 +73,7 @@ type sequenceDecs struct {
seqSize int
windowSize int
maxBits uint8
maxSyncLen uint64
}
// initialize all 3 decoders from the stream input.
@ -98,153 +99,13 @@ func (s *sequenceDecs) initialize(br *bitReader, hist *history, out []byte) erro
return nil
}
// decode sequences from the stream with the provided history.
func (s *sequenceDecs) decode(seqs []seqVals) error {
br := s.br
// Grab full sizes tables, to avoid bounds checks.
llTable, mlTable, ofTable := s.litLengths.fse.dt[:maxTablesize], s.matchLengths.fse.dt[:maxTablesize], s.offsets.fse.dt[:maxTablesize]
llState, mlState, ofState := s.litLengths.state.state, s.matchLengths.state.state, s.offsets.state.state
s.seqSize = 0
litRemain := len(s.literals)
maxBlockSize := maxCompressedBlockSize
if s.windowSize < maxBlockSize {
maxBlockSize = s.windowSize
}
for i := range seqs {
var ll, mo, ml int
if br.off > 4+((maxOffsetBits+16+16)>>3) {
// inlined function:
// ll, mo, ml = s.nextFast(br, llState, mlState, ofState)
// Final will not read from stream.
var llB, mlB, moB uint8
ll, llB = llState.final()
ml, mlB = mlState.final()
mo, moB = ofState.final()
// extra bits are stored in reverse order.
br.fillFast()
mo += br.getBits(moB)
if s.maxBits > 32 {
br.fillFast()
}
ml += br.getBits(mlB)
ll += br.getBits(llB)
if moB > 1 {
s.prevOffset[2] = s.prevOffset[1]
s.prevOffset[1] = s.prevOffset[0]
s.prevOffset[0] = mo
} else {
// mo = s.adjustOffset(mo, ll, moB)
// Inlined for rather big speedup
if ll == 0 {
// There is an exception though, when current sequence's literals_length = 0.
// In this case, repeated offsets are shifted by one, so an offset_value of 1 means Repeated_Offset2,
// an offset_value of 2 means Repeated_Offset3, and an offset_value of 3 means Repeated_Offset1 - 1_byte.
mo++
}
if mo == 0 {
mo = s.prevOffset[0]
} else {
var temp int
if mo == 3 {
temp = s.prevOffset[0] - 1
} else {
temp = s.prevOffset[mo]
}
if temp == 0 {
// 0 is not valid; input is corrupted; force offset to 1
println("WARNING: temp was 0")
temp = 1
}
if mo != 1 {
s.prevOffset[2] = s.prevOffset[1]
}
s.prevOffset[1] = s.prevOffset[0]
s.prevOffset[0] = temp
mo = temp
}
}
br.fillFast()
} else {
if br.overread() {
if debugDecoder {
printf("reading sequence %d, exceeded available data\n", i)
}
return io.ErrUnexpectedEOF
}
ll, mo, ml = s.next(br, llState, mlState, ofState)
br.fill()
}
if debugSequences {
println("Seq", i, "Litlen:", ll, "mo:", mo, "(abs) ml:", ml)
}
// Evaluate.
// We might be doing this async, so do it early.
if mo == 0 && ml > 0 {
return fmt.Errorf("zero matchoff and matchlen (%d) > 0", ml)
}
if ml > maxMatchLen {
return fmt.Errorf("match len (%d) bigger than max allowed length", ml)
}
s.seqSize += ll + ml
if s.seqSize > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", s.seqSize, maxBlockSize)
}
litRemain -= ll
if litRemain < 0 {
return fmt.Errorf("unexpected literal count, want %d bytes, but only %d is available", ll, litRemain+ll)
}
seqs[i] = seqVals{
ll: ll,
ml: ml,
mo: mo,
}
if i == len(seqs)-1 {
// This is the last sequence, so we shouldn't update state.
break
}
// Manually inlined, ~ 5-20% faster
// Update all 3 states at once. Approx 20% faster.
nBits := llState.nbBits() + mlState.nbBits() + ofState.nbBits()
if nBits == 0 {
llState = llTable[llState.newState()&maxTableMask]
mlState = mlTable[mlState.newState()&maxTableMask]
ofState = ofTable[ofState.newState()&maxTableMask]
} else {
bits := br.get32BitsFast(nBits)
lowBits := uint16(bits >> ((ofState.nbBits() + mlState.nbBits()) & 31))
llState = llTable[(llState.newState()+lowBits)&maxTableMask]
lowBits = uint16(bits >> (ofState.nbBits() & 31))
lowBits &= bitMask[mlState.nbBits()&15]
mlState = mlTable[(mlState.newState()+lowBits)&maxTableMask]
lowBits = uint16(bits) & bitMask[ofState.nbBits()&15]
ofState = ofTable[(ofState.newState()+lowBits)&maxTableMask]
}
}
s.seqSize += litRemain
if s.seqSize > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", s.seqSize, maxBlockSize)
}
err := br.close()
if err != nil {
printf("Closing sequences: %v, %+v\n", err, *br)
}
return err
}
// execute will execute the decoded sequence with the provided history.
// The sequence must be evaluated before being sent.
func (s *sequenceDecs) execute(seqs []seqVals, hist []byte) error {
if len(s.dict) == 0 {
return s.executeSimple(seqs, hist)
}
// Ensure we have enough output size...
if len(s.out)+s.seqSize > cap(s.out) {
addBytes := s.seqSize + len(s.out)
@ -327,6 +188,7 @@ func (s *sequenceDecs) execute(seqs []seqVals, hist []byte) error {
}
}
}
// Add final literals
copy(out[t:], s.literals)
if debugDecoder {
@ -341,14 +203,18 @@ func (s *sequenceDecs) execute(seqs []seqVals, hist []byte) error {
}
// decode sequences from the stream with the provided history.
func (s *sequenceDecs) decodeSync(history *history) error {
func (s *sequenceDecs) decodeSync(hist []byte) error {
supported, err := s.decodeSyncSimple(hist)
if supported {
return err
}
br := s.br
seqs := s.nSeqs
startSize := len(s.out)
// Grab full sizes tables, to avoid bounds checks.
llTable, mlTable, ofTable := s.litLengths.fse.dt[:maxTablesize], s.matchLengths.fse.dt[:maxTablesize], s.offsets.fse.dt[:maxTablesize]
llState, mlState, ofState := s.litLengths.state.state, s.matchLengths.state.state, s.offsets.state.state
hist := history.b[history.ignoreBuffer:]
out := s.out
maxBlockSize := maxCompressedBlockSize
if s.windowSize < maxBlockSize {
@ -433,7 +299,7 @@ func (s *sequenceDecs) decodeSync(history *history) error {
}
size := ll + ml + len(out)
if size-startSize > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", size, maxBlockSize)
return fmt.Errorf("output (%d) bigger than max block size (%d)", size-startSize, maxBlockSize)
}
if size > cap(out) {
// Not enough size, which can happen under high volume block streaming conditions
@ -463,13 +329,13 @@ func (s *sequenceDecs) decodeSync(history *history) error {
if mo > len(out)+len(hist) || mo > s.windowSize {
if len(s.dict) == 0 {
return fmt.Errorf("match offset (%d) bigger than current history (%d)", mo, len(out)+len(hist))
return fmt.Errorf("match offset (%d) bigger than current history (%d)", mo, len(out)+len(hist)-startSize)
}
// we may be in dictionary.
dictO := len(s.dict) - (mo - (len(out) + len(hist)))
if dictO < 0 || dictO >= len(s.dict) {
return fmt.Errorf("match offset (%d) bigger than current history (%d)", mo, len(out)+len(hist))
return fmt.Errorf("match offset (%d) bigger than current history (%d)", mo, len(out)+len(hist)-startSize)
}
end := dictO + ml
if end > len(s.dict) {
@ -530,6 +396,7 @@ func (s *sequenceDecs) decodeSync(history *history) error {
ofState = ofTable[ofState.newState()&maxTableMask]
} else {
bits := br.get32BitsFast(nBits)
lowBits := uint16(bits >> ((ofState.nbBits() + mlState.nbBits()) & 31))
llState = llTable[(llState.newState()+lowBits)&maxTableMask]
@ -543,8 +410,8 @@ func (s *sequenceDecs) decodeSync(history *history) error {
}
// Check if space for literals
if len(s.literals)+len(s.out)-startSize > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", len(s.out), maxBlockSize)
if size := len(s.literals) + len(s.out) - startSize; size > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", size, maxBlockSize)
}
// Add final literals
@ -552,16 +419,6 @@ func (s *sequenceDecs) decodeSync(history *history) error {
return br.close()
}
// update states, at least 27 bits must be available.
func (s *sequenceDecs) update(br *bitReader) {
// Max 8 bits
s.litLengths.state.next(br)
// Max 9 bits
s.matchLengths.state.next(br)
// Max 8 bits
s.offsets.state.next(br)
}
var bitMask [16]uint16
func init() {
@ -570,87 +427,6 @@ func init() {
}
}
// update states, at least 27 bits must be available.
func (s *sequenceDecs) updateAlt(br *bitReader) {
// Update all 3 states at once. Approx 20% faster.
a, b, c := s.litLengths.state.state, s.matchLengths.state.state, s.offsets.state.state
nBits := a.nbBits() + b.nbBits() + c.nbBits()
if nBits == 0 {
s.litLengths.state.state = s.litLengths.state.dt[a.newState()]
s.matchLengths.state.state = s.matchLengths.state.dt[b.newState()]
s.offsets.state.state = s.offsets.state.dt[c.newState()]
return
}
bits := br.get32BitsFast(nBits)
lowBits := uint16(bits >> ((c.nbBits() + b.nbBits()) & 31))
s.litLengths.state.state = s.litLengths.state.dt[a.newState()+lowBits]
lowBits = uint16(bits >> (c.nbBits() & 31))
lowBits &= bitMask[b.nbBits()&15]
s.matchLengths.state.state = s.matchLengths.state.dt[b.newState()+lowBits]
lowBits = uint16(bits) & bitMask[c.nbBits()&15]
s.offsets.state.state = s.offsets.state.dt[c.newState()+lowBits]
}
// nextFast will return new states when there are at least 4 unused bytes left on the stream when done.
func (s *sequenceDecs) nextFast(br *bitReader, llState, mlState, ofState decSymbol) (ll, mo, ml int) {
// Final will not read from stream.
ll, llB := llState.final()
ml, mlB := mlState.final()
mo, moB := ofState.final()
// extra bits are stored in reverse order.
br.fillFast()
mo += br.getBits(moB)
if s.maxBits > 32 {
br.fillFast()
}
ml += br.getBits(mlB)
ll += br.getBits(llB)
if moB > 1 {
s.prevOffset[2] = s.prevOffset[1]
s.prevOffset[1] = s.prevOffset[0]
s.prevOffset[0] = mo
return
}
// mo = s.adjustOffset(mo, ll, moB)
// Inlined for rather big speedup
if ll == 0 {
// There is an exception though, when current sequence's literals_length = 0.
// In this case, repeated offsets are shifted by one, so an offset_value of 1 means Repeated_Offset2,
// an offset_value of 2 means Repeated_Offset3, and an offset_value of 3 means Repeated_Offset1 - 1_byte.
mo++
}
if mo == 0 {
mo = s.prevOffset[0]
return
}
var temp int
if mo == 3 {
temp = s.prevOffset[0] - 1
} else {
temp = s.prevOffset[mo]
}
if temp == 0 {
// 0 is not valid; input is corrupted; force offset to 1
println("temp was 0")
temp = 1
}
if mo != 1 {
s.prevOffset[2] = s.prevOffset[1]
}
s.prevOffset[1] = s.prevOffset[0]
s.prevOffset[0] = temp
mo = temp
return
}
func (s *sequenceDecs) next(br *bitReader, llState, mlState, ofState decSymbol) (ll, mo, ml int) {
// Final will not read from stream.
ll, llB := llState.final()

View File

@ -0,0 +1,368 @@
//go:build amd64 && !appengine && !noasm && gc
// +build amd64,!appengine,!noasm,gc
package zstd
import (
"fmt"
"github.com/klauspost/compress/internal/cpuinfo"
)
type decodeSyncAsmContext struct {
llTable []decSymbol
mlTable []decSymbol
ofTable []decSymbol
llState uint64
mlState uint64
ofState uint64
iteration int
litRemain int
out []byte
outPosition int
literals []byte
litPosition int
history []byte
windowSize int
ll int // set on error (not for all errors, please refer to _generate/gen.go)
ml int // set on error (not for all errors, please refer to _generate/gen.go)
mo int // set on error (not for all errors, please refer to _generate/gen.go)
}
// sequenceDecs_decodeSync_amd64 implements the main loop of sequenceDecs.decodeSync in x86 asm.
//
// Please refer to seqdec_generic.go for the reference implementation.
//go:noescape
func sequenceDecs_decodeSync_amd64(s *sequenceDecs, br *bitReader, ctx *decodeSyncAsmContext) int
// sequenceDecs_decodeSync_bmi2 implements the main loop of sequenceDecs.decodeSync in x86 asm with BMI2 extensions.
//go:noescape
func sequenceDecs_decodeSync_bmi2(s *sequenceDecs, br *bitReader, ctx *decodeSyncAsmContext) int
// sequenceDecs_decodeSync_safe_amd64 does the same as above, but does not write more than output buffer.
//go:noescape
func sequenceDecs_decodeSync_safe_amd64(s *sequenceDecs, br *bitReader, ctx *decodeSyncAsmContext) int
// sequenceDecs_decodeSync_safe_bmi2 does the same as above, but does not write more than output buffer.
//go:noescape
func sequenceDecs_decodeSync_safe_bmi2(s *sequenceDecs, br *bitReader, ctx *decodeSyncAsmContext) int
// decode sequences from the stream with the provided history but without a dictionary.
func (s *sequenceDecs) decodeSyncSimple(hist []byte) (bool, error) {
if len(s.dict) > 0 {
return false, nil
}
if s.maxSyncLen == 0 && cap(s.out)-len(s.out) < maxCompressedBlockSize {
return false, nil
}
// FIXME: Using unsafe memory copies leads to rare, random crashes
// with fuzz testing. It is therefore disabled for now.
const useSafe = true
/*
useSafe := false
if s.maxSyncLen == 0 && cap(s.out)-len(s.out) < maxCompressedBlockSizeAlloc {
useSafe = true
}
if s.maxSyncLen > 0 && cap(s.out)-len(s.out)-compressedBlockOverAlloc < int(s.maxSyncLen) {
useSafe = true
}
if cap(s.literals) < len(s.literals)+compressedBlockOverAlloc {
useSafe = true
}
*/
br := s.br
maxBlockSize := maxCompressedBlockSize
if s.windowSize < maxBlockSize {
maxBlockSize = s.windowSize
}
ctx := decodeSyncAsmContext{
llTable: s.litLengths.fse.dt[:maxTablesize],
mlTable: s.matchLengths.fse.dt[:maxTablesize],
ofTable: s.offsets.fse.dt[:maxTablesize],
llState: uint64(s.litLengths.state.state),
mlState: uint64(s.matchLengths.state.state),
ofState: uint64(s.offsets.state.state),
iteration: s.nSeqs - 1,
litRemain: len(s.literals),
out: s.out,
outPosition: len(s.out),
literals: s.literals,
windowSize: s.windowSize,
history: hist,
}
s.seqSize = 0
startSize := len(s.out)
var errCode int
if cpuinfo.HasBMI2() {
if useSafe {
errCode = sequenceDecs_decodeSync_safe_bmi2(s, br, &ctx)
} else {
errCode = sequenceDecs_decodeSync_bmi2(s, br, &ctx)
}
} else {
if useSafe {
errCode = sequenceDecs_decodeSync_safe_amd64(s, br, &ctx)
} else {
errCode = sequenceDecs_decodeSync_amd64(s, br, &ctx)
}
}
switch errCode {
case noError:
break
case errorMatchLenOfsMismatch:
return true, fmt.Errorf("zero matchoff and matchlen (%d) > 0", ctx.ml)
case errorMatchLenTooBig:
return true, fmt.Errorf("match len (%d) bigger than max allowed length", ctx.ml)
case errorMatchOffTooBig:
return true, fmt.Errorf("match offset (%d) bigger than current history (%d)",
ctx.mo, ctx.outPosition+len(hist)-startSize)
case errorNotEnoughLiterals:
return true, fmt.Errorf("unexpected literal count, want %d bytes, but only %d is available",
ctx.ll, ctx.litRemain+ctx.ll)
case errorNotEnoughSpace:
size := ctx.outPosition + ctx.ll + ctx.ml
if debugDecoder {
println("msl:", s.maxSyncLen, "cap", cap(s.out), "bef:", startSize, "sz:", size-startSize, "mbs:", maxBlockSize, "outsz:", cap(s.out)-startSize)
}
return true, fmt.Errorf("output (%d) bigger than max block size (%d)", size-startSize, maxBlockSize)
default:
return true, fmt.Errorf("sequenceDecs_decode returned erronous code %d", errCode)
}
s.seqSize += ctx.litRemain
if s.seqSize > maxBlockSize {
return true, fmt.Errorf("output (%d) bigger than max block size (%d)", s.seqSize, maxBlockSize)
}
err := br.close()
if err != nil {
printf("Closing sequences: %v, %+v\n", err, *br)
return true, err
}
s.literals = s.literals[ctx.litPosition:]
t := ctx.outPosition
s.out = s.out[:t]
// Add final literals
s.out = append(s.out, s.literals...)
if debugDecoder {
t += len(s.literals)
if t != len(s.out) {
panic(fmt.Errorf("length mismatch, want %d, got %d", len(s.out), t))
}
}
return true, nil
}
// --------------------------------------------------------------------------------
type decodeAsmContext struct {
llTable []decSymbol
mlTable []decSymbol
ofTable []decSymbol
llState uint64
mlState uint64
ofState uint64
iteration int
seqs []seqVals
litRemain int
}
const noError = 0
// error reported when mo == 0 && ml > 0
const errorMatchLenOfsMismatch = 1
// error reported when ml > maxMatchLen
const errorMatchLenTooBig = 2
// error reported when mo > available history or mo > s.windowSize
const errorMatchOffTooBig = 3
// error reported when the sum of literal lengths exeeceds the literal buffer size
const errorNotEnoughLiterals = 4
// error reported when capacity of `out` is too small
const errorNotEnoughSpace = 5
// sequenceDecs_decode implements the main loop of sequenceDecs in x86 asm.
//
// Please refer to seqdec_generic.go for the reference implementation.
//go:noescape
func sequenceDecs_decode_amd64(s *sequenceDecs, br *bitReader, ctx *decodeAsmContext) int
// sequenceDecs_decode implements the main loop of sequenceDecs in x86 asm.
//
// Please refer to seqdec_generic.go for the reference implementation.
//go:noescape
func sequenceDecs_decode_56_amd64(s *sequenceDecs, br *bitReader, ctx *decodeAsmContext) int
// sequenceDecs_decode implements the main loop of sequenceDecs in x86 asm with BMI2 extensions.
//go:noescape
func sequenceDecs_decode_bmi2(s *sequenceDecs, br *bitReader, ctx *decodeAsmContext) int
// sequenceDecs_decode implements the main loop of sequenceDecs in x86 asm with BMI2 extensions.
//go:noescape
func sequenceDecs_decode_56_bmi2(s *sequenceDecs, br *bitReader, ctx *decodeAsmContext) int
// decode sequences from the stream without the provided history.
func (s *sequenceDecs) decode(seqs []seqVals) error {
br := s.br
maxBlockSize := maxCompressedBlockSize
if s.windowSize < maxBlockSize {
maxBlockSize = s.windowSize
}
ctx := decodeAsmContext{
llTable: s.litLengths.fse.dt[:maxTablesize],
mlTable: s.matchLengths.fse.dt[:maxTablesize],
ofTable: s.offsets.fse.dt[:maxTablesize],
llState: uint64(s.litLengths.state.state),
mlState: uint64(s.matchLengths.state.state),
ofState: uint64(s.offsets.state.state),
seqs: seqs,
iteration: len(seqs) - 1,
litRemain: len(s.literals),
}
s.seqSize = 0
lte56bits := s.maxBits+s.offsets.fse.actualTableLog+s.matchLengths.fse.actualTableLog+s.litLengths.fse.actualTableLog <= 56
var errCode int
if cpuinfo.HasBMI2() {
if lte56bits {
errCode = sequenceDecs_decode_56_bmi2(s, br, &ctx)
} else {
errCode = sequenceDecs_decode_bmi2(s, br, &ctx)
}
} else {
if lte56bits {
errCode = sequenceDecs_decode_56_amd64(s, br, &ctx)
} else {
errCode = sequenceDecs_decode_amd64(s, br, &ctx)
}
}
if errCode != 0 {
i := len(seqs) - ctx.iteration - 1
switch errCode {
case errorMatchLenOfsMismatch:
ml := ctx.seqs[i].ml
return fmt.Errorf("zero matchoff and matchlen (%d) > 0", ml)
case errorMatchLenTooBig:
ml := ctx.seqs[i].ml
return fmt.Errorf("match len (%d) bigger than max allowed length", ml)
case errorNotEnoughLiterals:
ll := ctx.seqs[i].ll
return fmt.Errorf("unexpected literal count, want %d bytes, but only %d is available", ll, ctx.litRemain+ll)
}
return fmt.Errorf("sequenceDecs_decode_amd64 returned erronous code %d", errCode)
}
if ctx.litRemain < 0 {
return fmt.Errorf("literal count is too big: total available %d, total requested %d",
len(s.literals), len(s.literals)-ctx.litRemain)
}
s.seqSize += ctx.litRemain
if s.seqSize > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", s.seqSize, maxBlockSize)
}
err := br.close()
if err != nil {
printf("Closing sequences: %v, %+v\n", err, *br)
}
return err
}
// --------------------------------------------------------------------------------
type executeAsmContext struct {
seqs []seqVals
seqIndex int
out []byte
history []byte
literals []byte
outPosition int
litPosition int
windowSize int
}
// sequenceDecs_executeSimple_amd64 implements the main loop of sequenceDecs.executeSimple in x86 asm.
//
// Returns false if a match offset is too big.
//
// Please refer to seqdec_generic.go for the reference implementation.
//go:noescape
func sequenceDecs_executeSimple_amd64(ctx *executeAsmContext) bool
// Same as above, but with safe memcopies
//go:noescape
func sequenceDecs_executeSimple_safe_amd64(ctx *executeAsmContext) bool
// executeSimple handles cases when dictionary is not used.
func (s *sequenceDecs) executeSimple(seqs []seqVals, hist []byte) error {
// Ensure we have enough output size...
if len(s.out)+s.seqSize+compressedBlockOverAlloc > cap(s.out) {
addBytes := s.seqSize + len(s.out) + compressedBlockOverAlloc
s.out = append(s.out, make([]byte, addBytes)...)
s.out = s.out[:len(s.out)-addBytes]
}
if debugDecoder {
printf("Execute %d seqs with literals: %d into %d bytes\n", len(seqs), len(s.literals), s.seqSize)
}
var t = len(s.out)
out := s.out[:t+s.seqSize]
ctx := executeAsmContext{
seqs: seqs,
seqIndex: 0,
out: out,
history: hist,
outPosition: t,
litPosition: 0,
literals: s.literals,
windowSize: s.windowSize,
}
var ok bool
if cap(s.literals) < len(s.literals)+compressedBlockOverAlloc {
ok = sequenceDecs_executeSimple_safe_amd64(&ctx)
} else {
ok = sequenceDecs_executeSimple_amd64(&ctx)
}
if !ok {
return fmt.Errorf("match offset (%d) bigger than current history (%d)",
seqs[ctx.seqIndex].mo, ctx.outPosition+len(hist))
}
s.literals = s.literals[ctx.litPosition:]
t = ctx.outPosition
// Add final literals
copy(out[t:], s.literals)
if debugDecoder {
t += len(s.literals)
if t != len(out) {
panic(fmt.Errorf("length mismatch, want %d, got %d, ss: %d", len(out), t, s.seqSize))
}
}
s.out = out
return nil
}

4100
vendor/github.com/klauspost/compress/zstd/seqdec_amd64.s generated vendored Normal file

File diff suppressed because it is too large Load Diff

View File

@ -0,0 +1,237 @@
//go:build !amd64 || appengine || !gc || noasm
// +build !amd64 appengine !gc noasm
package zstd
import (
"fmt"
"io"
)
// decode sequences from the stream with the provided history but without dictionary.
func (s *sequenceDecs) decodeSyncSimple(hist []byte) (bool, error) {
return false, nil
}
// decode sequences from the stream without the provided history.
func (s *sequenceDecs) decode(seqs []seqVals) error {
br := s.br
// Grab full sizes tables, to avoid bounds checks.
llTable, mlTable, ofTable := s.litLengths.fse.dt[:maxTablesize], s.matchLengths.fse.dt[:maxTablesize], s.offsets.fse.dt[:maxTablesize]
llState, mlState, ofState := s.litLengths.state.state, s.matchLengths.state.state, s.offsets.state.state
s.seqSize = 0
litRemain := len(s.literals)
maxBlockSize := maxCompressedBlockSize
if s.windowSize < maxBlockSize {
maxBlockSize = s.windowSize
}
for i := range seqs {
var ll, mo, ml int
if br.off > 4+((maxOffsetBits+16+16)>>3) {
// inlined function:
// ll, mo, ml = s.nextFast(br, llState, mlState, ofState)
// Final will not read from stream.
var llB, mlB, moB uint8
ll, llB = llState.final()
ml, mlB = mlState.final()
mo, moB = ofState.final()
// extra bits are stored in reverse order.
br.fillFast()
mo += br.getBits(moB)
if s.maxBits > 32 {
br.fillFast()
}
ml += br.getBits(mlB)
ll += br.getBits(llB)
if moB > 1 {
s.prevOffset[2] = s.prevOffset[1]
s.prevOffset[1] = s.prevOffset[0]
s.prevOffset[0] = mo
} else {
// mo = s.adjustOffset(mo, ll, moB)
// Inlined for rather big speedup
if ll == 0 {
// There is an exception though, when current sequence's literals_length = 0.
// In this case, repeated offsets are shifted by one, so an offset_value of 1 means Repeated_Offset2,
// an offset_value of 2 means Repeated_Offset3, and an offset_value of 3 means Repeated_Offset1 - 1_byte.
mo++
}
if mo == 0 {
mo = s.prevOffset[0]
} else {
var temp int
if mo == 3 {
temp = s.prevOffset[0] - 1
} else {
temp = s.prevOffset[mo]
}
if temp == 0 {
// 0 is not valid; input is corrupted; force offset to 1
println("WARNING: temp was 0")
temp = 1
}
if mo != 1 {
s.prevOffset[2] = s.prevOffset[1]
}
s.prevOffset[1] = s.prevOffset[0]
s.prevOffset[0] = temp
mo = temp
}
}
br.fillFast()
} else {
if br.overread() {
if debugDecoder {
printf("reading sequence %d, exceeded available data\n", i)
}
return io.ErrUnexpectedEOF
}
ll, mo, ml = s.next(br, llState, mlState, ofState)
br.fill()
}
if debugSequences {
println("Seq", i, "Litlen:", ll, "mo:", mo, "(abs) ml:", ml)
}
// Evaluate.
// We might be doing this async, so do it early.
if mo == 0 && ml > 0 {
return fmt.Errorf("zero matchoff and matchlen (%d) > 0", ml)
}
if ml > maxMatchLen {
return fmt.Errorf("match len (%d) bigger than max allowed length", ml)
}
s.seqSize += ll + ml
if s.seqSize > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", s.seqSize, maxBlockSize)
}
litRemain -= ll
if litRemain < 0 {
return fmt.Errorf("unexpected literal count, want %d bytes, but only %d is available", ll, litRemain+ll)
}
seqs[i] = seqVals{
ll: ll,
ml: ml,
mo: mo,
}
if i == len(seqs)-1 {
// This is the last sequence, so we shouldn't update state.
break
}
// Manually inlined, ~ 5-20% faster
// Update all 3 states at once. Approx 20% faster.
nBits := llState.nbBits() + mlState.nbBits() + ofState.nbBits()
if nBits == 0 {
llState = llTable[llState.newState()&maxTableMask]
mlState = mlTable[mlState.newState()&maxTableMask]
ofState = ofTable[ofState.newState()&maxTableMask]
} else {
bits := br.get32BitsFast(nBits)
lowBits := uint16(bits >> ((ofState.nbBits() + mlState.nbBits()) & 31))
llState = llTable[(llState.newState()+lowBits)&maxTableMask]
lowBits = uint16(bits >> (ofState.nbBits() & 31))
lowBits &= bitMask[mlState.nbBits()&15]
mlState = mlTable[(mlState.newState()+lowBits)&maxTableMask]
lowBits = uint16(bits) & bitMask[ofState.nbBits()&15]
ofState = ofTable[(ofState.newState()+lowBits)&maxTableMask]
}
}
s.seqSize += litRemain
if s.seqSize > maxBlockSize {
return fmt.Errorf("output (%d) bigger than max block size (%d)", s.seqSize, maxBlockSize)
}
err := br.close()
if err != nil {
printf("Closing sequences: %v, %+v\n", err, *br)
}
return err
}
// executeSimple handles cases when a dictionary is not used.
func (s *sequenceDecs) executeSimple(seqs []seqVals, hist []byte) error {
// Ensure we have enough output size...
if len(s.out)+s.seqSize > cap(s.out) {
addBytes := s.seqSize + len(s.out)
s.out = append(s.out, make([]byte, addBytes)...)
s.out = s.out[:len(s.out)-addBytes]
}
if debugDecoder {
printf("Execute %d seqs with literals: %d into %d bytes\n", len(seqs), len(s.literals), s.seqSize)
}
var t = len(s.out)
out := s.out[:t+s.seqSize]
for _, seq := range seqs {
// Add literals
copy(out[t:], s.literals[:seq.ll])
t += seq.ll
s.literals = s.literals[seq.ll:]
// Malformed input
if seq.mo > t+len(hist) || seq.mo > s.windowSize {
return fmt.Errorf("match offset (%d) bigger than current history (%d)", seq.mo, t+len(hist))
}
// Copy from history.
if v := seq.mo - t; v > 0 {
// v is the start position in history from end.
start := len(hist) - v
if seq.ml > v {
// Some goes into the current block.
// Copy remainder of history
copy(out[t:], hist[start:])
t += v
seq.ml -= v
} else {
copy(out[t:], hist[start:start+seq.ml])
t += seq.ml
continue
}
}
// We must be in the current buffer now
if seq.ml > 0 {
start := t - seq.mo
if seq.ml <= t-start {
// No overlap
copy(out[t:], out[start:start+seq.ml])
t += seq.ml
} else {
// Overlapping copy
// Extend destination slice and copy one byte at the time.
src := out[start : start+seq.ml]
dst := out[t:]
dst = dst[:len(src)]
t += len(src)
// Destination is the space we just added.
for i := range src {
dst[i] = src[i]
}
}
}
}
// Add final literals
copy(out[t:], s.literals)
if debugDecoder {
t += len(s.literals)
if t != len(out) {
panic(fmt.Errorf("length mismatch, want %d, got %d, ss: %d", len(out), t, s.seqSize))
}
}
s.out = out
return nil
}

View File

@ -18,26 +18,44 @@ const ZipMethodWinZip = 93
// See https://pkware.cachefly.net/webdocs/APPNOTE/APPNOTE-6.3.9.TXT
const ZipMethodPKWare = 20
var zipReaderPool sync.Pool
// zipReaderPool is the default reader pool.
var zipReaderPool = sync.Pool{New: func() interface{} {
z, err := NewReader(nil, WithDecoderLowmem(true), WithDecoderMaxWindow(128<<20), WithDecoderConcurrency(1))
if err != nil {
panic(err)
}
return z
}}
// newZipReader creates a pooled zip decompressor.
func newZipReader(r io.Reader) io.ReadCloser {
dec, ok := zipReaderPool.Get().(*Decoder)
if ok {
dec.Reset(r)
} else {
d, err := NewReader(r, WithDecoderConcurrency(1), WithDecoderLowmem(true))
if err != nil {
panic(err)
}
dec = d
func newZipReader(opts ...DOption) func(r io.Reader) io.ReadCloser {
pool := &zipReaderPool
if len(opts) > 0 {
opts = append([]DOption{WithDecoderLowmem(true), WithDecoderMaxWindow(128 << 20)}, opts...)
// Force concurrency 1
opts = append(opts, WithDecoderConcurrency(1))
// Create our own pool
pool = &sync.Pool{}
}
return func(r io.Reader) io.ReadCloser {
dec, ok := pool.Get().(*Decoder)
if ok {
dec.Reset(r)
} else {
d, err := NewReader(r, opts...)
if err != nil {
panic(err)
}
dec = d
}
return &pooledZipReader{dec: dec, pool: pool}
}
return &pooledZipReader{dec: dec}
}
type pooledZipReader struct {
mu sync.Mutex // guards Close and Read
dec *Decoder
mu sync.Mutex // guards Close and Read
pool *sync.Pool
dec *Decoder
}
func (r *pooledZipReader) Read(p []byte) (n int, err error) {
@ -48,8 +66,8 @@ func (r *pooledZipReader) Read(p []byte) (n int, err error) {
}
dec, err := r.dec.Read(p)
if err == io.EOF {
err = r.dec.Reset(nil)
zipReaderPool.Put(r.dec)
r.dec.Reset(nil)
r.pool.Put(r.dec)
r.dec = nil
}
return dec, err
@ -61,7 +79,7 @@ func (r *pooledZipReader) Close() error {
var err error
if r.dec != nil {
err = r.dec.Reset(nil)
zipReaderPool.Put(r.dec)
r.pool.Put(r.dec)
r.dec = nil
}
return err
@ -115,6 +133,9 @@ func ZipCompressor(opts ...EOption) func(w io.Writer) (io.WriteCloser, error) {
// ZipDecompressor returns a decompressor that can be registered with zip libraries.
// See ZipCompressor for example.
func ZipDecompressor() func(r io.Reader) io.ReadCloser {
return newZipReader
// Options can be specified. WithDecoderConcurrency(1) is forced,
// and by default a 128MB maximum decompression window is specified.
// The window size can be overridden if required.
func ZipDecompressor(opts ...DOption) func(r io.Reader) io.ReadCloser {
return newZipReader(opts...)
}

View File

@ -110,17 +110,6 @@ func printf(format string, a ...interface{}) {
}
}
// matchLenFast does matching, but will not match the last up to 7 bytes.
func matchLenFast(a, b []byte) int {
endI := len(a) & (math.MaxInt32 - 7)
for i := 0; i < endI; i += 8 {
if diff := load64(a, i) ^ load64(b, i); diff != 0 {
return i + bits.TrailingZeros64(diff)>>3
}
}
return endI
}
// matchLen returns the maximum length.
// a must be the shortest of the two.
// The function also returns whether all bytes matched.

5
vendor/modules.txt vendored
View File

@ -454,11 +454,12 @@ github.com/ishidawataru/sctp
# github.com/jmespath/go-jmespath v0.3.0
## explicit; go 1.14
github.com/jmespath/go-jmespath
# github.com/klauspost/compress v1.15.1
## explicit; go 1.15
# github.com/klauspost/compress v1.15.9
## explicit; go 1.16
github.com/klauspost/compress
github.com/klauspost/compress/fse
github.com/klauspost/compress/huff0
github.com/klauspost/compress/internal/cpuinfo
github.com/klauspost/compress/internal/snapref
github.com/klauspost/compress/zstd
github.com/klauspost/compress/zstd/internal/xxhash