Merge pull request #176 from sorpaas/master

Problem: block 46402, gas cost mismatch

regtests/src/bin/main.rs

@@ -66,7 +66,7 @@ fn handle_fire(client: &mut GethRPCClient, vm: &mut SeqTransactionVM, last_block
     loop {
         match vm.fire() {
             Ok(()) => {
-                println!("VM exited successfully, checking results ...");
+                println!("VM exited with {:?}.", vm.status());
                 break;
             },
             Err(RequireError::Account(address)) => {
@@ -132,7 +132,7 @@ fn test_block(client: &mut GethRPCClient, number: usize) {
 
         handle_fire(client, &mut vm, &format!("0x{:x}", last_number));
 
-        assert!(Gas::from_str(&receipt.gasUsed).unwrap() == vm.used_gas());
+        assert!(Gas::from_str(&receipt.gasUsed).unwrap() == vm.real_used_gas());
         assert!(receipt.logs.len() == vm.logs().len());
         for i in 0..receipt.logs.len() {
             assert!(from_rpc_log(&receipt.logs[i]) == vm.logs()[i]);

sputnikvm/src/vm/eval/mod.rs

@@ -371,4 +371,14 @@ impl<M: Memory + Default> Machine<M> {
     pub fn status(&self) -> MachineStatus {
         self.status.clone()
     }
+
+    /// If the machine is exited with EmptyGas, return gas_limit,
+    /// otherwise return the sum of memory gas and used gas.
+    pub fn real_used_gas(&self) -> Gas {
+        match self.status() {
+            MachineStatus::ExitedErr(MachineError::EmptyGas) =>
+                self.state.context.gas_limit,
+            _ => self.state.memory_gas() + self.state.used_gas,
+        }
+    }
 }

sputnikvm/src/vm/mod.rs

@@ -66,7 +66,7 @@ pub trait VM {
     fn accounts(&self) -> hash_map::Values<Address, Account>;
     fn out(&self) -> &[u8];
     fn available_gas(&self) -> Gas;
-    fn used_gas(&self) -> Gas;
+    fn real_used_gas(&self) -> Gas;
     fn refunded_gas(&self) -> Gas;
     fn logs(&self) -> &[Log];
 }
@@ -199,9 +199,10 @@ impl<M: Memory + Default> VM for ContextVM<M> {
         self.machines[0].state().available_gas()
     }
 
-    /// Returns the used gas of this VM.
-    fn used_gas(&self) -> Gas {
-        self.machines[0].state().memory_gas() + self.machines[0].state().used_gas
+    /// If the VM is exited with EmptyGas, return gas_limit,
+    /// otherwise return the sum of memory gas and used gas.
+    fn real_used_gas(&self) -> Gas {
+        self.machines[0].real_used_gas()
     }
 
     /// Returns the refunded gas of this VM.

sputnikvm/src/vm/transaction.rs

@@ -259,9 +259,9 @@ impl<M: Memory + Default> VM for TransactionVM<M> {
         }
     }
 
-    fn used_gas(&self) -> Gas {
+    fn real_used_gas(&self) -> Gas {
         match self.0 {
-            TransactionVMState::Running { ref vm, intrinsic_gas, .. } => vm.used_gas() + intrinsic_gas,
+            TransactionVMState::Running { ref vm, intrinsic_gas, .. } => vm.real_used_gas() + intrinsic_gas,
             TransactionVMState::Constructing { .. } => Gas::zero(),
         }
     }