execComputation and applyMessage unification

nimbus/vm/computation.nim

@@ -162,41 +162,46 @@ proc transferBalance(computation: var BaseComputation, opCode: static[Op]): bool
 
   result = true
 
-proc executeOpcodes*(computation: var BaseComputation)
+proc executeOpcodes*(computation: var BaseComputation) {.gcsafe.}
 
-proc applyMessage(fork: Fork, computation: var BaseComputation, opCode: static[Op]) =
+proc applyMessage*(computation: var BaseComputation, opCode: static[Op]): bool =
   var snapshot = computation.snapshot()
   defer: snapshot.dispose()
 
   when opCode in {CallCode, Call, Create}:
-    if not computation.transferBalance(opCode): 
+    if not computation.transferBalance(opCode):
       snapshot.revert()
       return
-  
+
   if computation.gasMeter.gasRemaining < 0:
     snapshot.commit()
     return
 
-  var success = true
   try:
     executeOpcodes(computation)
-    success = not computation.isError
+    result = not computation.isError
   except VMError:
-    success = false
-    debug "applyMessage failed",
+    result = false
+    debug "applyMessage VM Error",
+      msg = getCurrentExceptionMsg(),
+      depth = computation.msg.depth
+  except ValueError:
+    result = false
+    debug "applyMessage Value Error",
       msg = getCurrentExceptionMsg(),
       depth = computation.msg.depth
 
-  if success and computation.msg.isCreate:
+  if result and computation.msg.isCreate:
+    var fork = computation.getFork
     let contractFailed = not computation.writeContract(fork)
-    success = not(contractFailed and fork == FkHomestead)
+    result = not(contractFailed and fork == FkHomestead)
 
-  if success:
+  if result:
     snapshot.commit()
   else:
     snapshot.revert(true)
 
-proc addChildComputation(fork: Fork, computation: var BaseComputation, child: BaseComputation) =
+proc addChildComputation(computation: var BaseComputation, child: BaseComputation) =
   if child.isError:
     if child.msg.isCreate:
       computation.returnData = child.output
@@ -216,9 +221,8 @@ proc addChildComputation(fork: Fork, computation: var BaseComputation, child: Ba
 
 proc applyChildComputation*(parentComp, childComp: var BaseComputation, opCode: static[Op]) =
   ## Apply the vm message childMsg as a child computation.
-  var fork = parentComp.getFork
-  fork.applyMessage(childComp, opCode)
-  fork.addChildComputation(parentComp, childComp)
+  discard childComp.applyMessage(opCode)
+  parentComp.addChildComputation(childComp)
 
 proc registerAccountForDeletion*(c: var BaseComputation, beneficiary: EthAddress) =
   if c.msg.storageAddress in c.accountsToDelete:

nimbus/vm_state_transactions.nim

@@ -64,36 +64,18 @@ proc setupComputation*(vmState: BaseVMState, tx: Transaction, sender, recipient:
   doAssert result.isOriginComputation
 
 proc execComputation*(computation: var BaseComputation): bool =
-  var snapshot = computation.snapshot()
-  defer: snapshot.dispose()
+  if computation.msg.isCreate:
+    result = computation.applyMessage(Create)
+  else:
+    result = computation.applyMessage(Call)
 
   computation.vmState.mutateStateDB:
-    db.subBalance(computation.msg.origin, computation.msg.value)
-    db.addBalance(computation.msg.storageAddress, computation.msg.value)
-
-  try:
-    computation.executeOpcodes()
-    computation.vmState.mutateStateDB:
-      for deletedAccount in computation.getAccountsForDeletion:
-        db.deleteAccount deletedAccount
-    result = not computation.isError
-  except VMError:
-    result = false
-    debug "execComputation() VM Error", error = getCurrentExceptionMsg()
-  except ValueError:
-    result = false
-    debug "execComputation() Value Error", msg = getCurrentExceptionMsg()
-
-  if result and computation.msg.isCreate:
-    let fork = computation.getFork
-    let contractFailed = not computation.writeContract(fork)
-    result = not(contractFailed and fork == FkHomestead)
+    for deletedAccount in computation.getAccountsForDeletion:
+      db.deleteAccount deletedAccount
 
   if result:
-    snapshot.commit()
     computation.vmState.addLogs(computation.logEntries)
   else:
-    snapshot.revert()
     if computation.tracingEnabled: computation.traceError()
 
 proc refundGas*(computation: BaseComputation, tx: Transaction, sender: EthAddress): GasInt =