evm: add some mulmod benches (#10600)

* evm: add blockhash_mulmod bench

* evm: use num-bigint for mod ops

ethcore/evm/Cargo.toml

@@ -14,6 +14,7 @@ vm = { path = "../vm" }
 keccak-hash = "0.1"
 parking_lot = "0.7"
 memory-cache = { path = "../../util/memory-cache" }
+num-bigint = "0.2"
 
 [dev-dependencies]
 rustc-hex = "1.0"

ethcore/evm/benches/basic.rs

@@ -45,7 +45,9 @@ criterion_group!(
 	mem_gas_calculation_same_usize,
 	mem_gas_calculation_same_u256,
 	mem_gas_calculation_increasing_usize,
-	mem_gas_calculation_increasing_u256
+	mem_gas_calculation_increasing_u256,
+	blockhash_mulmod_small,
+	blockhash_mulmod_large,
 );
 criterion_main!(basic);
 
@@ -150,6 +152,54 @@ fn mem_gas_calculation_increasing(gas: U256, b: &mut Bencher) {
 	});
 }
 
+fn blockhash_mulmod_small(b: &mut Criterion) {
+	b.bench_function("blockhash_mulmod_small", |b| {
+		let factory = Factory::default();
+		let mut ext = FakeExt::new();
+
+		let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
+
+		b.iter(|| {
+			let code = black_box(
+				"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".from_hex().unwrap()
+			);
+
+			let mut params = ActionParams::default();
+			params.address = address.clone();
+			params.gas = U256::from(4_000u64);
+			params.code = Some(Arc::new(code.clone()));
+
+			let vm = factory.create(params, ext.schedule(), 0);
+
+			result(vm.exec(&mut ext).ok().unwrap())
+		});
+	});
+}
+
+fn blockhash_mulmod_large(b: &mut Criterion) {
+	b.bench_function("blockhash_mulmod_large", |b| {
+		let factory = Factory::default();
+		let mut ext = FakeExt::new();
+
+		let address = Address::from_str("0f572e5295c57f15886f9b263e2f6d2d6c7b5ec6").unwrap();
+
+		b.iter(|| {
+			let code = black_box(
+				"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".from_hex().unwrap()
+			);
+
+			let mut params = ActionParams::default();
+			params.address = address.clone();
+			params.gas = U256::from(4_000u64);
+			params.code = Some(Arc::new(code.clone()));
+
+			let vm = factory.create(params, ext.schedule(), 0);
+
+			result(vm.exec(&mut ext).ok().unwrap())
+		});
+	});
+}
+
 fn result(r: Result<evm::GasLeft>) -> U256 {
 	match r {
 		Ok(GasLeft::Known(gas_left)) => gas_left,

ethcore/evm/src/interpreter/mod.rs

@@ -28,7 +28,8 @@ use std::{cmp, mem};
 use std::sync::Arc;
 use hash::keccak;
 use bytes::Bytes;
-use ethereum_types::{U256, U512, H256, Address};
+use ethereum_types::{U256, H256, Address};
+use num_bigint::BigUint;
 
 use vm::{
 	self, ActionParams, ParamsType, ActionValue, CallType, MessageCallResult,
@@ -61,6 +62,17 @@ const TWO_POW_96: U256 = U256([0, 0x100000000, 0, 0]); //0x1 00000000 00000000 0
 const TWO_POW_224: U256 = U256([0, 0, 0, 0x100000000]); //0x1 00000000 00000000 00000000 00000000 00000000 00000000 00000000
 const TWO_POW_248: U256 = U256([0, 0, 0, 0x100000000000000]); //0x1 00000000 00000000 00000000 00000000 00000000 00000000 00000000 000000
 
+fn to_biguint(x: U256) -> BigUint {
+	let mut bytes = [0u8; 32];
+	x.to_little_endian(&mut bytes);
+	BigUint::from_bytes_le(&bytes)
+}
+
+fn from_biguint(x: BigUint) -> U256 {
+	let bytes = x.to_bytes_le();
+	U256::from_little_endian(&bytes)
+}
+
 /// Abstraction over raw vector of Bytes. Easier state management of PC.
 struct CodeReader {
 	position: ProgramCounter,
@@ -1009,11 +1021,12 @@ impl<Cost: CostType> Interpreter<Cost> {
 				let c = self.stack.pop_back();
 
 				self.stack.push(if !c.is_zero() {
-					// upcast to 512
-					let a5 = U512::from(a);
-					let res = a5.overflowing_add(U512::from(b)).0;
-					let x = res % U512::from(c);
-					U256::from(x)
+					let a_num = to_biguint(a);
+					let b_num = to_biguint(b);
+					let c_num = to_biguint(c);
+					let res = a_num + b_num;
+					let x = res % c_num;
+					from_biguint(x)
 				} else {
 					U256::zero()
 				});
@@ -1024,10 +1037,12 @@ impl<Cost: CostType> Interpreter<Cost> {
 				let c = self.stack.pop_back();
 
 				self.stack.push(if !c.is_zero() {
-					let a5 = U512::from(a);
-					let res = a5.overflowing_mul(U512::from(b)).0;
-					let x = res % U512::from(c);
-					U256::from(x)
+					let a_num = to_biguint(a);
+					let b_num = to_biguint(b);
+					let c_num = to_biguint(c);
+					let res = a_num * b_num;
+					let x = res % c_num;
+					from_biguint(x)
 				} else {
 					U256::zero()
 				});

ethcore/evm/src/lib.rs

@@ -24,6 +24,7 @@ extern crate vm;
 extern crate keccak_hash as hash;
 extern crate memory_cache;
 extern crate parity_bytes as bytes;
+extern crate num_bigint;
 
 #[macro_use]
 extern crate lazy_static;