[VOL-4291] Rw-core updates for gRPC migration
Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/klauspost/compress/zstd/fse_predefined.go b/vendor/github.com/klauspost/compress/zstd/fse_predefined.go
new file mode 100644
index 0000000..474cb77
--- /dev/null
+++ b/vendor/github.com/klauspost/compress/zstd/fse_predefined.go
@@ -0,0 +1,158 @@
+// Copyright 2019+ Klaus Post. All rights reserved.
+// License information can be found in the LICENSE file.
+// Based on work by Yann Collet, released under BSD License.
+
+package zstd
+
+import (
+ "fmt"
+ "math"
+ "sync"
+)
+
+var (
+ // fsePredef are the predefined fse tables as defined here:
+ // https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#default-distributions
+ // These values are already transformed.
+ fsePredef [3]fseDecoder
+
+ // fsePredefEnc are the predefined encoder based on fse tables as defined here:
+ // https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#default-distributions
+ // These values are already transformed.
+ fsePredefEnc [3]fseEncoder
+
+ // symbolTableX contain the transformations needed for each type as defined in
+ // https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#the-codes-for-literals-lengths-match-lengths-and-offsets
+ symbolTableX [3][]baseOffset
+
+ // maxTableSymbol is the biggest supported symbol for each table type
+ // https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#the-codes-for-literals-lengths-match-lengths-and-offsets
+ maxTableSymbol = [3]uint8{tableLiteralLengths: maxLiteralLengthSymbol, tableOffsets: maxOffsetLengthSymbol, tableMatchLengths: maxMatchLengthSymbol}
+
+ // bitTables is the bits table for each table.
+ bitTables = [3][]byte{tableLiteralLengths: llBitsTable[:], tableOffsets: nil, tableMatchLengths: mlBitsTable[:]}
+)
+
+type tableIndex uint8
+
+const (
+ // indexes for fsePredef and symbolTableX
+ tableLiteralLengths tableIndex = 0
+ tableOffsets tableIndex = 1
+ tableMatchLengths tableIndex = 2
+
+ maxLiteralLengthSymbol = 35
+ maxOffsetLengthSymbol = 30
+ maxMatchLengthSymbol = 52
+)
+
+// baseOffset is used for calculating transformations.
+type baseOffset struct {
+ baseLine uint32
+ addBits uint8
+}
+
+// fillBase will precalculate base offsets with the given bit distributions.
+func fillBase(dst []baseOffset, base uint32, bits ...uint8) {
+ if len(bits) != len(dst) {
+ panic(fmt.Sprintf("len(dst) (%d) != len(bits) (%d)", len(dst), len(bits)))
+ }
+ for i, bit := range bits {
+ if base > math.MaxInt32 {
+ panic("invalid decoding table, base overflows int32")
+ }
+
+ dst[i] = baseOffset{
+ baseLine: base,
+ addBits: bit,
+ }
+ base += 1 << bit
+ }
+}
+
+var predef sync.Once
+
+func initPredefined() {
+ predef.Do(func() {
+ // Literals length codes
+ tmp := make([]baseOffset, 36)
+ for i := range tmp[:16] {
+ tmp[i] = baseOffset{
+ baseLine: uint32(i),
+ addBits: 0,
+ }
+ }
+ fillBase(tmp[16:], 16, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
+ symbolTableX[tableLiteralLengths] = tmp
+
+ // Match length codes
+ tmp = make([]baseOffset, 53)
+ for i := range tmp[:32] {
+ tmp[i] = baseOffset{
+ // The transformation adds the 3 length.
+ baseLine: uint32(i) + 3,
+ addBits: 0,
+ }
+ }
+ fillBase(tmp[32:], 35, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16)
+ symbolTableX[tableMatchLengths] = tmp
+
+ // Offset codes
+ tmp = make([]baseOffset, maxOffsetBits+1)
+ tmp[1] = baseOffset{
+ baseLine: 1,
+ addBits: 1,
+ }
+ fillBase(tmp[2:], 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
+ symbolTableX[tableOffsets] = tmp
+
+ // Fill predefined tables and transform them.
+ // https://github.com/facebook/zstd/blob/dev/doc/zstd_compression_format.md#default-distributions
+ for i := range fsePredef[:] {
+ f := &fsePredef[i]
+ switch tableIndex(i) {
+ case tableLiteralLengths:
+ // https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L243
+ f.actualTableLog = 6
+ copy(f.norm[:], []int16{4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1,
+ 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1,
+ -1, -1, -1, -1})
+ f.symbolLen = 36
+ case tableOffsets:
+ // https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L281
+ f.actualTableLog = 5
+ copy(f.norm[:], []int16{
+ 1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1})
+ f.symbolLen = 29
+ case tableMatchLengths:
+ //https://github.com/facebook/zstd/blob/ededcfca57366461021c922720878c81a5854a0a/lib/decompress/zstd_decompress_block.c#L304
+ f.actualTableLog = 6
+ copy(f.norm[:], []int16{
+ 1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
+ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1,
+ -1, -1, -1, -1, -1})
+ f.symbolLen = 53
+ }
+ if err := f.buildDtable(); err != nil {
+ panic(fmt.Errorf("building table %v: %v", tableIndex(i), err))
+ }
+ if err := f.transform(symbolTableX[i]); err != nil {
+ panic(fmt.Errorf("building table %v: %v", tableIndex(i), err))
+ }
+ f.preDefined = true
+
+ // Create encoder as well
+ enc := &fsePredefEnc[i]
+ copy(enc.norm[:], f.norm[:])
+ enc.symbolLen = f.symbolLen
+ enc.actualTableLog = f.actualTableLog
+ if err := enc.buildCTable(); err != nil {
+ panic(fmt.Errorf("building encoding table %v: %v", tableIndex(i), err))
+ }
+ enc.setBits(bitTables[i])
+ enc.preDefined = true
+ }
+ })
+}