From c1d516546d221de898ddeb12a77477d992d125df Mon Sep 17 00:00:00 2001 From: Ethan Buchman Date: Thu, 6 Aug 2015 03:11:10 -0400 Subject: [PATCH] faster hex-prefix codec and string -> []byte --- trie/encoding.go | 43 +++++++++++++++++-------------------------- trie/encoding_test.go | 10 +++++----- trie/iterator.go | 2 +- trie/shortnode.go | 4 ++-- trie/trie.go | 10 +++++----- 5 files changed, 30 insertions(+), 39 deletions(-) diff --git a/trie/encoding.go b/trie/encoding.go index 524807f06b..8daf503a3f 100644 --- a/trie/encoding.go +++ b/trie/encoding.go @@ -18,11 +18,9 @@ package trie import ( "bytes" - "encoding/hex" - "strings" ) -func CompactEncode(hexSlice []byte) string { +func CompactEncode(hexSlice []byte) []byte { terminator := 0 if hexSlice[len(hexSlice)-1] == 16 { terminator = 1 @@ -45,10 +43,10 @@ func CompactEncode(hexSlice []byte) string { buff.WriteByte(byte(16*hexSlice[i] + hexSlice[i+1])) } - return buff.String() + return buff.Bytes() } -func CompactDecode(str string) []byte { +func CompactDecode(str []byte) []byte { base := CompactHexDecode(str) base = base[:len(base)-1] if base[0] >= 2 { @@ -63,30 +61,23 @@ func CompactDecode(str string) []byte { return base } -func CompactHexDecode(str string) []byte { - base := "0123456789abcdef" - var hexSlice []byte +func CompactHexDecode(str []byte) []byte { + var nibbles []byte - enc := hex.EncodeToString([]byte(str)) - for _, v := range enc { - hexSlice = append(hexSlice, byte(strings.IndexByte(base, byte(v)))) + for _, b := range str { + nibbles = append(nibbles, b/16) + nibbles = append(nibbles, b%16) } - hexSlice = append(hexSlice, 16) - - return hexSlice + nibbles = append(nibbles, 16) + return nibbles } -func DecodeCompact(key []byte) string { - const base = "0123456789abcdef" - var str string - - for _, v := range key { - if v < 16 { - str += string(base[v]) - } +// assumes key is odd length +func DecodeCompact(key []byte) []byte { + var res []byte + for i := 0; i < len(key)-1; i += 2 { + v1, v0 := key[i], key[i+1] + res = append(res, v1*16+v0) } - - res, _ := hex.DecodeString(str) - - return string(res) + return res } diff --git a/trie/encoding_test.go b/trie/encoding_test.go index e52c6ba8d8..faaa7f5833 100644 --- a/trie/encoding_test.go +++ b/trie/encoding_test.go @@ -48,28 +48,28 @@ func (s *TrieEncodingSuite) TestCompactEncode(c *checker.C) { func (s *TrieEncodingSuite) TestCompactHexDecode(c *checker.C) { exp := []byte{7, 6, 6, 5, 7, 2, 6, 2, 16} - res := CompactHexDecode("verb") + res := CompactHexDecode([]byte("verb")) c.Assert(res, checker.DeepEquals, exp) } func (s *TrieEncodingSuite) TestCompactDecode(c *checker.C) { // odd compact decode exp := []byte{1, 2, 3, 4, 5} - res := CompactDecode("\x11\x23\x45") + res := CompactDecode([]byte("\x11\x23\x45")) c.Assert(res, checker.DeepEquals, exp) // even compact decode exp = []byte{0, 1, 2, 3, 4, 5} - res = CompactDecode("\x00\x01\x23\x45") + res = CompactDecode([]byte("\x00\x01\x23\x45")) c.Assert(res, checker.DeepEquals, exp) // even terminated compact decode exp = []byte{0, 15, 1, 12, 11, 8 /*term*/, 16} - res = CompactDecode("\x20\x0f\x1c\xb8") + res = CompactDecode([]byte("\x20\x0f\x1c\xb8")) c.Assert(res, checker.DeepEquals, exp) // even terminated compact decode exp = []byte{15, 1, 12, 11, 8 /*term*/, 16} - res = CompactDecode("\x3f\x1c\xb8") + res = CompactDecode([]byte("\x3f\x1c\xb8")) c.Assert(res, checker.DeepEquals, exp) } diff --git a/trie/iterator.go b/trie/iterator.go index 698e64b34d..9c4c7fbe5b 100644 --- a/trie/iterator.go +++ b/trie/iterator.go @@ -41,7 +41,7 @@ func (self *Iterator) Next() bool { self.Key = make([]byte, 32) } - key := RemTerm(CompactHexDecode(string(self.Key))) + key := RemTerm(CompactHexDecode(self.Key)) k := self.next(self.trie.root, key, isIterStart) self.Key = []byte(DecodeCompact(k)) diff --git a/trie/shortnode.go b/trie/shortnode.go index b5fc6d1f95..569d5f1096 100644 --- a/trie/shortnode.go +++ b/trie/shortnode.go @@ -26,7 +26,7 @@ type ShortNode struct { } func NewShortNode(t *Trie, key []byte, value Node) *ShortNode { - return &ShortNode{t, []byte(CompactEncode(key)), value, false} + return &ShortNode{t, CompactEncode(key), value, false} } func (self *ShortNode) Value() Node { self.value = self.trie.trans(self.value) @@ -49,7 +49,7 @@ func (self *ShortNode) Hash() interface{} { } func (self *ShortNode) Key() []byte { - return CompactDecode(string(self.key)) + return CompactDecode(self.key) } func (self *ShortNode) setDirty(dirty bool) { diff --git a/trie/trie.go b/trie/trie.go index e7ee864021..abf48a8509 100644 --- a/trie/trie.go +++ b/trie/trie.go @@ -69,7 +69,7 @@ func (self *Trie) Iterator() *Iterator { func (self *Trie) Copy() *Trie { cpy := make([]byte, 32) - copy(cpy, self.roothash) + copy(cpy, self.roothash) // NOTE: cpy isn't being used anywhere? trie := New(nil, nil) trie.cache = self.cache.Copy() if self.root != nil { @@ -131,7 +131,7 @@ func (self *Trie) Update(key, value []byte) Node { self.mu.Lock() defer self.mu.Unlock() - k := CompactHexDecode(string(key)) + k := CompactHexDecode(key) if len(value) != 0 { node := NewValueNode(self, value) @@ -149,7 +149,7 @@ func (self *Trie) Get(key []byte) []byte { self.mu.Lock() defer self.mu.Unlock() - k := CompactHexDecode(string(key)) + k := CompactHexDecode(key) n := self.get(self.root, k) if n != nil { @@ -164,7 +164,7 @@ func (self *Trie) Delete(key []byte) Node { self.mu.Lock() defer self.mu.Unlock() - k := CompactHexDecode(string(key)) + k := CompactHexDecode(key) self.root = self.delete(self.root, k) return self.root @@ -336,7 +336,7 @@ func (self *Trie) mknode(value *common.Value) Node { case 2: // A value node may consists of 2 bytes. if value.Get(0).Len() != 0 { - key := CompactDecode(string(value.Get(0).Bytes())) + key := CompactDecode(value.Get(0).Bytes()) if key[len(key)-1] == 16 { return NewShortNode(self, key, NewValueNode(self, value.Get(1).Bytes())) } else {