Merge PR: add HashDataWithCache for opSha3 (#7)

* commit

* delete unless code

* Update crypto.go

core/vm/instructions.go

@@ -19,6 +19,7 @@ package vm
 import (
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/params"
 	"github.com/holiman/uint256"
 	"golang.org/x/crypto/sha3"
@@ -237,11 +238,8 @@ func opSha3(pc *uint64, interpreter *EVMInterpreter, scope *ScopeContext) ([]byt
 
 	if interpreter.hasher == nil {
 		interpreter.hasher = sha3.NewLegacyKeccak256().(keccakState)
-	} else {
-		interpreter.hasher.Reset()
 	}
-	interpreter.hasher.Write(data)
-	interpreter.hasher.Read(interpreter.hasherBuf[:])
+	interpreter.hasherBuf = crypto.HashDataWithCache(interpreter.hasher, data)
 
 	evm := interpreter.evm
 	if evm.Config.EnablePreimageRecording {

crypto/crypto.go

@@ -24,6 +24,7 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
+	"github.com/VictoriaMetrics/fastcache"
 	"hash"
 	"io"
 	"io/ioutil"
@@ -45,9 +46,12 @@ const RecoveryIDOffset = 64
 // DigestLength sets the signature digest exact length
 const DigestLength = 32
 
+const hashCacheSize = 256 * 1024 * 1024
+
 var (
 	secp256k1N, _  = new(big.Int).SetString("fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141", 16)
 	secp256k1halfN = new(big.Int).Div(secp256k1N, big.NewInt(2))
+	hashCache      = fastcache.New(hashCacheSize)
 )
 
 var errInvalidPubkey = errors.New("invalid secp256k1 public key")
@@ -73,6 +77,33 @@ func HashData(kh KeccakState, data []byte) (h common.Hash) {
 	return h
 }
 
+// HashDataWithCache hashes the provided data using the KeccakState and returns a 32 byte hash;
+// when len(data) is belong to (0,96], cache will be used;
+// design for hashing common.Address, common.Hash and opSha3
+func HashDataWithCache(kh KeccakState, data []byte) (h common.Hash) {
+	l := len(data)
+	if l > 0 && l <= 96 {
+		if _, ok := hashCache.HasGet(h[:0], data); ok {
+			return
+		}
+	}
+
+	d := kh
+	if d == nil {
+		d = NewKeccakState()
+	} else {
+		d.Reset()
+	}
+	d.Write(data)
+	d.Read(h[:])
+
+	if l > 0 && l <= 96 {
+		hashCache.Set(data, h[:])
+	}
+
+	return
+}
+
 // Keccak256 calculates and returns the Keccak256 hash of the input data.
 func Keccak256(data ...[]byte) []byte {
 	b := make([]byte, 32)