added benchmarks and few optimisations for rlp encoding

benches/rlp.rs

@@ -10,19 +10,53 @@ extern crate test;
 extern crate ethcore_util;
 
 use test::Bencher;
-use ethcore_util::rlp;
+use std::str::FromStr;
 use ethcore_util::rlp::{RlpStream, Rlp, Decodable};
+use ethcore_util::uint::U256;
 
 #[bench]
-fn bench_stream_value(b: &mut Bencher) {
+fn bench_stream_u64_value(b: &mut Bencher) {
     b.iter( || {
         //1029
         let mut stream = RlpStream::new();
-        stream.append(&1029u32);
+        stream.append(&1029u64);
         let _ = stream.out().unwrap();
     });
 }
 
+#[bench]
+fn bench_decode_u64_value(b: &mut Bencher) {
+    b.iter( || {
+        // 1029
+        let data = vec![0x82, 0x04, 0x05]; 
+        let rlp = Rlp::new(&data);
+        let _ = u64::decode(&rlp).unwrap();
+    });
+}
+
+#[bench]
+fn bench_stream_u256_value(b: &mut Bencher) {
+    b.iter( || {
+        //u256
+        let mut stream = RlpStream::new();
+        stream.append(&U256::from_str("8090a0b0c0d0e0f00910203040506077000000000000000100000000000012f0").unwrap());
+        let _ = stream.out().unwrap();
+    });
+}
+
+#[bench]
+fn bench_decode_u256_value(b: &mut Bencher) {
+    b.iter( || {
+        // u256
+        let data = vec![0xa0, 0x80, 0x90, 0xa0, 0xb0, 0xc0, 0xd0, 0xe0, 0xf0,
+                       0x09, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x77,
+                       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,
+                       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x12, 0xf0];
+        let rlp = Rlp::new(&data);
+        let _ = U256::decode(&rlp).unwrap();
+    });
+}
+
 #[bench]
 fn bench_stream_nested_empty_lists(b: &mut Bencher) {
     b.iter( || {
@@ -41,17 +75,17 @@ fn bench_decode_nested_empty_lists(b: &mut Bencher) {
         // [ [], [[]], [ [], [[]] ] ]
         let data = vec![0xc7, 0xc0, 0xc1, 0xc0, 0xc3, 0xc0, 0xc1, 0xc0];
         let rlp = Rlp::new(&data);
-        let v0: Vec<u8> = Decodable::decode(&rlp.at(0).unwrap()).unwrap();
-        let v1: Vec<Vec<u8>> = Decodable::decode(&rlp.at(1).unwrap()).unwrap();
-        let v2a: Vec<u8> = Decodable::decode(&rlp.at(2).unwrap().at(0).unwrap()).unwrap();
-        let v2b: Vec<Vec<u8>> = Decodable::decode(&rlp.at(2).unwrap().at(1).unwrap()).unwrap();
+        let _v0: Vec<u8> = Decodable::decode(&rlp.at(0).unwrap()).unwrap();
+        let _v1: Vec<Vec<u8>> = Decodable::decode(&rlp.at(1).unwrap()).unwrap();
+        let _v2a: Vec<u8> = Decodable::decode(&rlp.at(2).unwrap().at(0).unwrap()).unwrap();
+        let _v2b: Vec<Vec<u8>> = Decodable::decode(&rlp.at(2).unwrap().at(1).unwrap()).unwrap();
     });
 }
 
 #[bench]
 fn bench_stream_1000_empty_lists(b: &mut Bencher) {
     b.iter( || {
-        let mut stream = RlpStream::new();
+        let mut stream = RlpStream::new_list(1000);
         for _ in 0..1000 {
             stream.append_list(0);
         }

src/bytes.rs

@@ -60,6 +60,7 @@ impl ToBytes for u64 {
     fn to_bytes(&self) -> Vec<u8> {
         let mut res= vec![];
         let count = self.to_bytes_len();
+        res.reserve(count);
         for i in 0..count {
             let j = count - 1 - i;
             res.push((*self >> (j * 8)) as u8);
@@ -89,6 +90,7 @@ macro_rules! impl_uint_to_bytes {
             fn to_bytes(&self) -> Vec<u8> { 
                 let mut res= vec![];
                 let count = self.to_bytes_len();
+                res.reserve(count);
                 for i in 0..count {
                     let j = count - 1 - i;
                     res.push(self.byte(j));

src/uint.rs

@@ -233,7 +233,6 @@ macro_rules! construct_uint {
             type Err = FromHexError;
 
             fn from_str(value: &str) -> Result<$name, Self::Err> {
-                println!("{}", value);
                 let bytes: &[u8] = &try!(value.from_hex());
                 Ok(From::from(bytes))
             }