Decouple virtual machines (#6184)

* work in progress for splitting vms

* evm working

* Evm -> Vm

* wasm converted

* ethcore working

* test fixes

ethcore/Cargo.toml

@@ -53,6 +53,8 @@ semver = "0.6"
 stats = { path = "../util/stats" }
 time = "0.1"
 transient-hashmap = "0.4"
+vm = { path = "vm" }
+wasm = { path = "wasm" }
 
 [dev-dependencies]
 native-contracts = { path = "native_contracts", features = ["test_contracts"] }

ethcore/evm/Cargo.toml

@@ -13,6 +13,7 @@ ethjson = { path = "../../json" }
 lazy_static = "0.2"
 log = "0.3"
 rlp = { path = "../../util/rlp" }
+vm = { path = "../vm" }
 parity-wasm = "0.12"
 wasm-utils = { git = "https://github.com/paritytech/wasm-utils" }
 

ethcore/evm/src/benches/mod.rs

@@ -25,7 +25,7 @@ extern crate test;
 use self::test::{Bencher, black_box};
 
 use util::*;
-use evm::action_params::ActionParams;
+use vm::ActionParams;
 use evm::{self, Factory, VMType};
 use evm::tests::FakeExt;
 

ethcore/evm/src/evm.rs

@@ -17,142 +17,8 @@
 //! Evm interface.
 
 use std::{ops, cmp, fmt};
-use util::{U128, U256, U512, trie};
-use action_params::ActionParams;
-use {Ext};
-
-use super::wasm;
-
-/// Evm errors.
-#[derive(Debug, Clone, PartialEq)]
-pub enum Error {
-	/// `OutOfGas` is returned when transaction execution runs out of gas.
-	/// The state should be reverted to the state from before the
-	/// transaction execution. But it does not mean that transaction
-	/// was invalid. Balance still should be transfered and nonce
-	/// should be increased.
-	OutOfGas,
-	/// `BadJumpDestination` is returned when execution tried to move
-	/// to position that wasn't marked with JUMPDEST instruction
-	BadJumpDestination {
-		/// Position the code tried to jump to.
-		destination: usize
-	},
-	/// `BadInstructions` is returned when given instruction is not supported
-	BadInstruction {
-		/// Unrecognized opcode
-		instruction: u8,
-	},
-	/// `StackUnderflow` when there is not enough stack elements to execute instruction
-	StackUnderflow {
-		/// Invoked instruction
-		instruction: &'static str,
-		/// How many stack elements was requested by instruction
-		wanted: usize,
-		/// How many elements were on stack
-		on_stack: usize
-	},
-	/// When execution would exceed defined Stack Limit
-	OutOfStack {
-		/// Invoked instruction
-		instruction: &'static str,
-		/// How many stack elements instruction wanted to push
-		wanted: usize,
-		/// What was the stack limit
-		limit: usize
-	},
-	/// Built-in contract failed on given input
-	BuiltIn(&'static str),
-	/// When execution tries to modify the state in static context
-	MutableCallInStaticContext,
-	/// Likely to cause consensus issues.
-	Internal(String),
-	/// Wasm runtime error
-	Wasm(String),
-}
-
-impl From<Box<trie::TrieError>> for Error {
-	fn from(err: Box<trie::TrieError>) -> Self {
-		Error::Internal(format!("Internal error: {}", err))
-	}
-}
-
-impl From<wasm::RuntimeError> for Error {
-	fn from(err: wasm::RuntimeError) -> Self {
-		Error::Wasm(format!("Runtime error: {:?}", err))
-	}
-}
-
-impl fmt::Display for Error {
-	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-		use self::Error::*;
-		match *self {
-			OutOfGas => write!(f, "Out of gas"),
-			BadJumpDestination { destination } => write!(f, "Bad jump destination {:x}", destination),
-			BadInstruction { instruction } => write!(f, "Bad instruction {:x}",  instruction),
-			StackUnderflow { instruction, wanted, on_stack } => write!(f, "Stack underflow {} {}/{}", instruction, wanted, on_stack),
-			OutOfStack { instruction, wanted, limit } => write!(f, "Out of stack {} {}/{}", instruction, wanted, limit),
-			BuiltIn(name) => write!(f, "Built-in failed: {}", name),
-			Internal(ref msg) => write!(f, "Internal error: {}", msg),
-			MutableCallInStaticContext => write!(f, "Mutable call in static context"),
-			Wasm(ref msg) => write!(f, "Internal error: {}", msg),
-		}
-	}
-}
-
-/// A specialized version of Result over EVM errors.
-pub type Result<T> = ::std::result::Result<T, Error>;
-
-/// Return data buffer. Holds memory from a previous call and a slice into that memory.
-#[derive(Debug)]
-pub struct ReturnData {
-	mem: Vec<u8>,
-	offset: usize,
-	size: usize,
-}
-
-impl ::std::ops::Deref for ReturnData {
-	type Target = [u8];
-	fn deref(&self) -> &[u8] {
-		&self.mem[self.offset..self.offset + self.size]
-	}
-}
-
-impl ReturnData {
-	/// Create empty `ReturnData`.
-	pub fn empty() -> Self {
-		ReturnData {
-			mem: Vec::new(),
-			offset: 0,
-			size: 0,
-		}
-	}
-	/// Create `ReturnData` from give buffer and slice.
-	pub fn new(mem: Vec<u8>, offset: usize, size: usize) -> Self {
-		ReturnData {
-			mem: mem,
-			offset: offset,
-			size: size,
-		}
-	}
-}
-
-/// Gas Left: either it is a known value, or it needs to be computed by processing
-/// a return instruction.
-#[derive(Debug)]
-pub enum GasLeft {
-	/// Known gas left
-	Known(U256),
-	/// Return or Revert instruction must be processed.
-	NeedsReturn {
-		/// Amount of gas left.
-		gas_left: U256,
-		/// Return data buffer.
-		data: ReturnData,
-		/// Apply or revert state changes on revert.
-		apply_state: bool
-	},
-}
+use util::{U128, U256, U512};
+use vm::{Ext, Result, ReturnData, GasLeft, Error};
 
 /// Finalization result. Gas Left: either it is a known value, or it needs to be computed by processing
 /// a return instruction.
@@ -281,15 +147,6 @@ impl CostType for usize {
 	}
 }
 
-/// Evm interface
-pub trait Evm {
-	/// This function should be used to execute transaction.
-	///
-	/// It returns either an error, a known amount of gas left, or parameters to be used
-	/// to compute the final gas left.
-	fn exec(&mut self, params: ActionParams, ext: &mut Ext) -> Result<GasLeft>;
-}
-
 #[cfg(test)]
 mod tests {
 	use util::U256;

ethcore/evm/src/factory.rs

@@ -17,7 +17,7 @@
 //! Evm factory.
 //!
 use std::sync::Arc;
-use evm::Evm;
+use vm::Vm;
 use util::U256;
 use super::interpreter::SharedCache;
 use super::vmtype::VMType;
@@ -33,7 +33,7 @@ impl Factory {
 	/// Create fresh instance of VM
 	/// Might choose implementation depending on supplied gas.
 	#[cfg(feature = "jit")]
-	pub fn create(&self, gas: U256) -> Box<Evm> {
+	pub fn create(&self, gas: U256) -> Box<Vm> {
 		match self.evm {
 			VMType::Jit => {
 				Box::new(super::jit::JitEvm::default())
@@ -49,7 +49,7 @@ impl Factory {
 	/// Create fresh instance of VM
 	/// Might choose implementation depending on supplied gas.
 	#[cfg(not(feature = "jit"))]
-	pub fn create(&self, gas: U256) -> Box<Evm> {
+	pub fn create(&self, gas: U256) -> Box<Vm> {
 		match self.evm {
 			VMType::Interpreter => if Self::can_fit_in_usize(gas) {
 				Box::new(super::interpreter::Interpreter::<usize>::new(self.evm_cache.clone()))

ethcore/evm/src/interpreter/gasometer.rs

@@ -17,15 +17,15 @@
 use util::*;
 use super::u256_to_address;
 
-use {evm, ext};
+use {evm, vm};
 use instructions::{self, Instruction, InstructionInfo};
 use interpreter::stack::Stack;
-use schedule::Schedule;
+use vm::Schedule;
 
 macro_rules! overflowing {
 	($x: expr) => {{
 		let (v, overflow) = $x;
-		if overflow { return Err(evm::Error::OutOfGas); }
+		if overflow { return Err(vm::Error::OutOfGas); }
 		v
 	}}
 }
@@ -59,16 +59,16 @@ impl<Gas: evm::CostType> Gasometer<Gas> {
 		}
 	}
 
-	pub fn verify_gas(&self, gas_cost: &Gas) -> evm::Result<()> {
+	pub fn verify_gas(&self, gas_cost: &Gas) -> vm::Result<()> {
 		match &self.current_gas < gas_cost {
-			true => Err(evm::Error::OutOfGas),
+			true => Err(vm::Error::OutOfGas),
 			false => Ok(())
 		}
 	}
 
 	/// How much gas is provided to a CALL/CREATE, given that we need to deduct `needed` for this operation
 	/// and that we `requested` some.
-	pub fn gas_provided(&self, schedule: &Schedule, needed: Gas, requested: Option<U256>) -> evm::Result<Gas> {
+	pub fn gas_provided(&self, schedule: &Schedule, needed: Gas, requested: Option<U256>) -> vm::Result<Gas> {
 		// Try converting requested gas to `Gas` (`U256/u64`)
 		// but in EIP150 even if we request more we should never fail from OOG
 		let requested = requested.map(Gas::from_u256);
@@ -107,12 +107,12 @@ impl<Gas: evm::CostType> Gasometer<Gas> {
 	/// it will be the amount of gas that the current context provides to the child context.
 	pub fn requirements(
 		&mut self,
-		ext: &ext::Ext,
+		ext: &vm::Ext,
 		instruction: Instruction,
 		info: &InstructionInfo,
 		stack: &Stack<U256>,
 		current_mem_size: usize,
-	) -> evm::Result<InstructionRequirements<Gas>> {
+	) -> vm::Result<InstructionRequirements<Gas>> {
 		let schedule = ext.schedule();
 		let tier = instructions::get_tier_idx(info.tier);
 		let default_gas = Gas::from(schedule.tier_step_gas[tier]);
@@ -291,7 +291,7 @@ impl<Gas: evm::CostType> Gasometer<Gas> {
 		})
 	}
 
-	fn mem_gas_cost(&self, schedule: &Schedule, current_mem_size: usize, mem_size: &Gas) -> evm::Result<(Gas, Gas, usize)> {
+	fn mem_gas_cost(&self, schedule: &Schedule, current_mem_size: usize, mem_size: &Gas) -> vm::Result<(Gas, Gas, usize)> {
 		let gas_for_mem = |mem_size: Gas| {
 			let s = mem_size >> 5;
 			// s * memory_gas + s * s / quad_coeff_div
@@ -319,12 +319,12 @@ impl<Gas: evm::CostType> Gasometer<Gas> {
 
 
 #[inline]
-fn mem_needed_const<Gas: evm::CostType>(mem: &U256, add: usize) -> evm::Result<Gas> {
+fn mem_needed_const<Gas: evm::CostType>(mem: &U256, add: usize) -> vm::Result<Gas> {
 	Gas::from_u256(overflowing!(mem.overflowing_add(U256::from(add))))
 }
 
 #[inline]
-fn mem_needed<Gas: evm::CostType>(offset: &U256, size: &U256) -> evm::Result<Gas> {
+fn mem_needed<Gas: evm::CostType>(offset: &U256, size: &U256) -> vm::Result<Gas> {
 	if size.is_zero() {
 		return Ok(Gas::from(0));
 	}

ethcore/evm/src/interpreter/memory.rs

@@ -15,7 +15,7 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
 use util::U256;
-use {ReturnData};
+use vm::ReturnData;
 
 const MAX_RETURN_WASTE_BYTES: usize = 16384;