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Diffstat (limited to 'vendor/github.com/klauspost/compress/s2/encode_go.go')
-rw-r--r--vendor/github.com/klauspost/compress/s2/encode_go.go298
1 files changed, 0 insertions, 298 deletions
diff --git a/vendor/github.com/klauspost/compress/s2/encode_go.go b/vendor/github.com/klauspost/compress/s2/encode_go.go
deleted file mode 100644
index 43d43534e..000000000
--- a/vendor/github.com/klauspost/compress/s2/encode_go.go
+++ /dev/null
@@ -1,298 +0,0 @@
-//go:build !amd64 || appengine || !gc || noasm
-// +build !amd64 appengine !gc noasm
-
-package s2
-
-import (
- "math/bits"
-)
-
-// encodeBlock encodes a non-empty src to a guaranteed-large-enough dst. It
-// assumes that the varint-encoded length of the decompressed bytes has already
-// been written.
-//
-// It also assumes that:
-// len(dst) >= MaxEncodedLen(len(src))
-func encodeBlock(dst, src []byte) (d int) {
- if len(src) < minNonLiteralBlockSize {
- return 0
- }
- return encodeBlockGo(dst, src)
-}
-
-// encodeBlockBetter encodes a non-empty src to a guaranteed-large-enough dst. It
-// assumes that the varint-encoded length of the decompressed bytes has already
-// been written.
-//
-// It also assumes that:
-// len(dst) >= MaxEncodedLen(len(src))
-func encodeBlockBetter(dst, src []byte) (d int) {
- return encodeBlockBetterGo(dst, src)
-}
-
-// encodeBlockBetter encodes a non-empty src to a guaranteed-large-enough dst. It
-// assumes that the varint-encoded length of the decompressed bytes has already
-// been written.
-//
-// It also assumes that:
-// len(dst) >= MaxEncodedLen(len(src))
-func encodeBlockBetterSnappy(dst, src []byte) (d int) {
- return encodeBlockBetterSnappyGo(dst, src)
-}
-
-// encodeBlock encodes a non-empty src to a guaranteed-large-enough dst. It
-// assumes that the varint-encoded length of the decompressed bytes has already
-// been written.
-//
-// It also assumes that:
-// len(dst) >= MaxEncodedLen(len(src))
-func encodeBlockSnappy(dst, src []byte) (d int) {
- if len(src) < minNonLiteralBlockSize {
- return 0
- }
- return encodeBlockSnappyGo(dst, src)
-}
-
-// emitLiteral writes a literal chunk and returns the number of bytes written.
-//
-// It assumes that:
-// dst is long enough to hold the encoded bytes
-// 0 <= len(lit) && len(lit) <= math.MaxUint32
-func emitLiteral(dst, lit []byte) int {
- if len(lit) == 0 {
- return 0
- }
- const num = 63<<2 | tagLiteral
- i, n := 0, uint(len(lit)-1)
- switch {
- case n < 60:
- dst[0] = uint8(n)<<2 | tagLiteral
- i = 1
- case n < 1<<8:
- dst[1] = uint8(n)
- dst[0] = 60<<2 | tagLiteral
- i = 2
- case n < 1<<16:
- dst[2] = uint8(n >> 8)
- dst[1] = uint8(n)
- dst[0] = 61<<2 | tagLiteral
- i = 3
- case n < 1<<24:
- dst[3] = uint8(n >> 16)
- dst[2] = uint8(n >> 8)
- dst[1] = uint8(n)
- dst[0] = 62<<2 | tagLiteral
- i = 4
- default:
- dst[4] = uint8(n >> 24)
- dst[3] = uint8(n >> 16)
- dst[2] = uint8(n >> 8)
- dst[1] = uint8(n)
- dst[0] = 63<<2 | tagLiteral
- i = 5
- }
- return i + copy(dst[i:], lit)
-}
-
-// emitRepeat writes a repeat chunk and returns the number of bytes written.
-// Length must be at least 4 and < 1<<24
-func emitRepeat(dst []byte, offset, length int) int {
- // Repeat offset, make length cheaper
- length -= 4
- if length <= 4 {
- dst[0] = uint8(length)<<2 | tagCopy1
- dst[1] = 0
- return 2
- }
- if length < 8 && offset < 2048 {
- // Encode WITH offset
- dst[1] = uint8(offset)
- dst[0] = uint8(offset>>8)<<5 | uint8(length)<<2 | tagCopy1
- return 2
- }
- if length < (1<<8)+4 {
- length -= 4
- dst[2] = uint8(length)
- dst[1] = 0
- dst[0] = 5<<2 | tagCopy1
- return 3
- }
- if length < (1<<16)+(1<<8) {
- length -= 1 << 8
- dst[3] = uint8(length >> 8)
- dst[2] = uint8(length >> 0)
- dst[1] = 0
- dst[0] = 6<<2 | tagCopy1
- return 4
- }
- const maxRepeat = (1 << 24) - 1
- length -= 1 << 16
- left := 0
- if length > maxRepeat {
- left = length - maxRepeat + 4
- length = maxRepeat - 4
- }
- dst[4] = uint8(length >> 16)
- dst[3] = uint8(length >> 8)
- dst[2] = uint8(length >> 0)
- dst[1] = 0
- dst[0] = 7<<2 | tagCopy1
- if left > 0 {
- return 5 + emitRepeat(dst[5:], offset, left)
- }
- return 5
-}
-
-// emitCopy writes a copy chunk and returns the number of bytes written.
-//
-// It assumes that:
-// dst is long enough to hold the encoded bytes
-// 1 <= offset && offset <= math.MaxUint32
-// 4 <= length && length <= 1 << 24
-func emitCopy(dst []byte, offset, length int) int {
- if offset >= 65536 {
- i := 0
- if length > 64 {
- // Emit a length 64 copy, encoded as 5 bytes.
- dst[4] = uint8(offset >> 24)
- dst[3] = uint8(offset >> 16)
- dst[2] = uint8(offset >> 8)
- dst[1] = uint8(offset)
- dst[0] = 63<<2 | tagCopy4
- length -= 64
- if length >= 4 {
- // Emit remaining as repeats
- return 5 + emitRepeat(dst[5:], offset, length)
- }
- i = 5
- }
- if length == 0 {
- return i
- }
- // Emit a copy, offset encoded as 4 bytes.
- dst[i+0] = uint8(length-1)<<2 | tagCopy4
- dst[i+1] = uint8(offset)
- dst[i+2] = uint8(offset >> 8)
- dst[i+3] = uint8(offset >> 16)
- dst[i+4] = uint8(offset >> 24)
- return i + 5
- }
-
- // Offset no more than 2 bytes.
- if length > 64 {
- // Emit a length 60 copy, encoded as 3 bytes.
- // Emit remaining as repeat value (minimum 4 bytes).
- dst[2] = uint8(offset >> 8)
- dst[1] = uint8(offset)
- dst[0] = 59<<2 | tagCopy2
- length -= 60
- // Emit remaining as repeats, at least 4 bytes remain.
- return 3 + emitRepeat(dst[3:], offset, length)
- }
- if length >= 12 || offset >= 2048 {
- // Emit the remaining copy, encoded as 3 bytes.
- dst[2] = uint8(offset >> 8)
- dst[1] = uint8(offset)
- dst[0] = uint8(length-1)<<2 | tagCopy2
- return 3
- }
- // Emit the remaining copy, encoded as 2 bytes.
- dst[1] = uint8(offset)
- dst[0] = uint8(offset>>8)<<5 | uint8(length-4)<<2 | tagCopy1
- return 2
-}
-
-// emitCopyNoRepeat writes a copy chunk and returns the number of bytes written.
-//
-// It assumes that:
-// dst is long enough to hold the encoded bytes
-// 1 <= offset && offset <= math.MaxUint32
-// 4 <= length && length <= 1 << 24
-func emitCopyNoRepeat(dst []byte, offset, length int) int {
- if offset >= 65536 {
- i := 0
- if length > 64 {
- // Emit a length 64 copy, encoded as 5 bytes.
- dst[4] = uint8(offset >> 24)
- dst[3] = uint8(offset >> 16)
- dst[2] = uint8(offset >> 8)
- dst[1] = uint8(offset)
- dst[0] = 63<<2 | tagCopy4
- length -= 64
- if length >= 4 {
- // Emit remaining as repeats
- return 5 + emitCopyNoRepeat(dst[5:], offset, length)
- }
- i = 5
- }
- if length == 0 {
- return i
- }
- // Emit a copy, offset encoded as 4 bytes.
- dst[i+0] = uint8(length-1)<<2 | tagCopy4
- dst[i+1] = uint8(offset)
- dst[i+2] = uint8(offset >> 8)
- dst[i+3] = uint8(offset >> 16)
- dst[i+4] = uint8(offset >> 24)
- return i + 5
- }
-
- // Offset no more than 2 bytes.
- if length > 64 {
- // Emit a length 60 copy, encoded as 3 bytes.
- // Emit remaining as repeat value (minimum 4 bytes).
- dst[2] = uint8(offset >> 8)
- dst[1] = uint8(offset)
- dst[0] = 59<<2 | tagCopy2
- length -= 60
- // Emit remaining as repeats, at least 4 bytes remain.
- return 3 + emitCopyNoRepeat(dst[3:], offset, length)
- }
- if length >= 12 || offset >= 2048 {
- // Emit the remaining copy, encoded as 3 bytes.
- dst[2] = uint8(offset >> 8)
- dst[1] = uint8(offset)
- dst[0] = uint8(length-1)<<2 | tagCopy2
- return 3
- }
- // Emit the remaining copy, encoded as 2 bytes.
- dst[1] = uint8(offset)
- dst[0] = uint8(offset>>8)<<5 | uint8(length-4)<<2 | tagCopy1
- return 2
-}
-
-// matchLen returns how many bytes match in a and b
-//
-// It assumes that:
-// len(a) <= len(b)
-//
-func matchLen(a []byte, b []byte) int {
- b = b[:len(a)]
- var checked int
- if len(a) > 4 {
- // Try 4 bytes first
- if diff := load32(a, 0) ^ load32(b, 0); diff != 0 {
- return bits.TrailingZeros32(diff) >> 3
- }
- // Switch to 8 byte matching.
- checked = 4
- a = a[4:]
- b = b[4:]
- for len(a) >= 8 {
- b = b[:len(a)]
- if diff := load64(a, 0) ^ load64(b, 0); diff != 0 {
- return checked + (bits.TrailingZeros64(diff) >> 3)
- }
- checked += 8
- a = a[8:]
- b = b[8:]
- }
- }
- b = b[:len(a)]
- for i := range a {
- if a[i] != b[i] {
- return int(i) + checked
- }
- }
- return len(a) + checked
-}
generated by cgit v1.2.3 (git 2.46.0) at 2025-08-05 00:11:51 +0000