diff --git a/core/vm/gas.go b/core/vm/gas.go
index e64810cd5..2d5d7ae18 100644
--- a/core/vm/gas.go
+++ b/core/vm/gas.go
@@ -61,8 +61,8 @@ func baseCheck(op OpCode, stack *stack, gas *big.Int) error {
 	if op >= PUSH1 && op <= PUSH32 {
 		op = PUSH1
 	}
-	if op >= SWAP1 && op <= SWAP16 {
-		op = SWAP1
+	if op >= DUP1 && op <= DUP16 {
+		op = DUP1
 	}
 
 	if r, ok := _baseCheck[op]; ok {
@@ -71,7 +71,7 @@ func baseCheck(op OpCode, stack *stack, gas *big.Int) error {
 			return err
 		}
 
-		if r.stackPush && len(stack.data)-r.stackPop == 1024 {
+		if r.stackPush && len(stack.data)-r.stackPop+1 > 1024 {
 			return fmt.Errorf("stack limit reached (%d)", maxStack)
 		}
 
@@ -154,6 +154,6 @@ var _baseCheck = map[OpCode]req{
 	JUMPDEST:     {0, GasJumpDest, false},
 	SUICIDE:      {1, Zero, false},
 	RETURN:       {2, Zero, false},
-	PUSH1:        {0, GasFastStep, true},
+	PUSH1:        {0, GasFastestStep, true},
 	DUP1:         {0, Zero, true},
 }
diff --git a/core/vm/vm.go b/core/vm/vm.go
index 0618446c2..88fbdf763 100644
--- a/core/vm/vm.go
+++ b/core/vm/vm.go
@@ -45,23 +45,7 @@ func (self *Vm) Run(context *Context, callData []byte) (ret []byte, err error) {
 
 	self.Printf("(%d) (%x) %x (code=%d) gas: %v (d) %x", self.env.Depth(), caller.Address().Bytes()[:4], context.Address(), len(code), context.Gas, callData).Endl()
 
-	/*
-		if self.Recoverable {
-			// Recover from any require exception
-			defer func() {
-				if r := recover(); r != nil {
-					self.Printf(" %v", r).Endl()
-
-					context.UseGas(context.Gas)
-
-					ret = context.Return(nil)
-
-					err = fmt.Errorf("%v", r)
-				}
-			}()
-		}
-	*/
-
+	// User defer pattern to check for an error and, based on the error being nil or not, use all gas and return.
 	defer func() {
 		if err != nil {
 			self.Printf(" %v", err).Endl()