core, tests: reduced state copy by N calls

Reduced the amount of state copied that are required by N calls by doing
a balance check prior to any state modifications.

1 files changed, 4 insertions, 0 deletions

diff --git a/core/vm_env.go b/core/vm_env.go
index c1a86d63e..719829543 100644
--- a/core/vm_env.go
+++ b/core/vm_env.go
@@ -69,6 +69,10 @@ func (self *VMEnv) GetHash(n uint64) common.Hash {
 func (self *VMEnv) AddLog(log *state.Log) {
 	self.state.AddLog(log)
 }
+func (self *VMEnv) CanTransfer(from vm.Account, balance *big.Int) bool {
+	return from.Balance().Cmp(balance) >= 0
+}
+
 func (self *VMEnv) Transfer(from, to vm.Account, amount *big.Int) error {
 	return vm.Transfer(from, to, amount)
 }