crypto: less allocations when hashing and tx handling (ethereum#21265)

Author: gzliudan

crypto/crypto.go

@@ -75,7 +75,7 @@ func HashData(kh KeccakState, data []byte) (h common.Hash) {
 // Keccak256 calculates and returns the Keccak256 hash of the input data.
 func Keccak256(data ...[]byte) []byte {
 	b := make([]byte, 32)
-	d := NewKeccakState()
+	d := sha3.NewLegacyKeccak256().(KeccakState)
 	for _, b := range data {
 		d.Write(b)
 	}
@@ -86,7 +86,7 @@ func Keccak256(data ...[]byte) []byte {
 // Keccak256Hash calculates and returns the Keccak256 hash of the input data,
 // converting it to an internal Hash data structure.
 func Keccak256Hash(data ...[]byte) (h common.Hash) {
-	d := NewKeccakState()
+	d := sha3.NewLegacyKeccak256().(KeccakState)
 	for _, b := range data {
 		d.Write(b)
 	}