core, core/state, trie: EIP158, reprice & skip empty account write

This commit implements EIP158 part 1, 2, 3 & 4

1. If an account is empty it's no longer written to the trie. An empty
  account is defined as (balance=0, nonce=0, storage=0, code=0).
2. Delete an empty account if it's touched
3. An empty account is redefined as either non-existent or empty.
4. Zero value calls and zero value suicides no longer consume the 25k
  reation costs.

params: moved core/config to params

Signed-off-by: Jeffrey Wilcke <jeffrey@ethereum.org>

1 files changed, 26 insertions, 6 deletions

diff --git a/core/vm/vm.go b/core/vm/vm.go
index 09cddc2f8..6e316acda 100644
--- a/core/vm/vm.go
+++ b/core/vm/vm.go
@@ -51,9 +51,9 @@ type EVM struct {
 func New(env Environment, cfg Config) *EVM {
 	return &EVM{
 		env:       env,
-		jumpTable: newJumpTable(env.RuleSet(), env.BlockNumber()),
+		jumpTable: newJumpTable(env.ChainConfig(), env.BlockNumber()),
 		cfg:       cfg,
-		gasTable:  env.RuleSet().GasTable(env.BlockNumber()),
+		gasTable:  env.ChainConfig().GasTable(env.BlockNumber()),
 	}
 }
 
@@ -172,6 +172,7 @@ func (evm *EVM) Run(contract *Contract, input []byte) (ret []byte, err error) {
 
 		// Get the memory location of pc
 		op = contract.GetOp(pc)
+		//fmt.Printf("OP %d %v\n", op, op)
 		// calculate the new memory size and gas price for the current executing opcode
 		newMemSize, cost, err = calculateGasAndSize(evm.gasTable, evm.env, contract, caller, op, statedb, mem, stack)
 		if err != nil {
@@ -254,10 +255,20 @@ func calculateGasAndSize(gasTable params.GasTable, env Environment, contract *Co
 	// stack Check, memory resize & gas phase
 	switch op {
 	case SUICIDE:
-		// if suicide is not nil: homestead gas fork
+		// EIP150 homestead gas reprice fork:
 		if gasTable.CreateBySuicide != nil {
 			gas.Set(gasTable.Suicide)
-			if !env.Db().Exist(common.BigToAddress(stack.data[len(stack.data)-1])) {
+			var (
+				address = common.BigToAddress(stack.data[len(stack.data)-1])
+				eip158  = env.ChainConfig().IsEIP158(env.BlockNumber())
+			)
+
+			if eip158 {
+				// if empty and transfers value
+				if env.Db().Empty(address) && statedb.GetBalance(contract.Address()).BitLen() > 0 {
+					gas.Add(gas, gasTable.CreateBySuicide)
+				}
+			} else if !env.Db().Exist(address) {
 				gas.Add(gas, gasTable.CreateBySuicide)
 			}
 		}
@@ -378,12 +389,21 @@ func calculateGasAndSize(gasTable params.GasTable, env Environment, contract *Co
 	case CALL, CALLCODE:
 		gas.Set(gasTable.Calls)
 
+		transfersValue := stack.data[len(stack.data)-3].BitLen() > 0
 		if op == CALL {
-			if !env.Db().Exist(common.BigToAddress(stack.data[stack.len()-2])) {
+			var (
+				address = common.BigToAddress(stack.data[len(stack.data)-2])
+				eip158  = env.ChainConfig().IsEIP158(env.BlockNumber())
+			)
+			if eip158 {
+				if env.Db().Empty(address) && transfersValue {
+					gas.Add(gas, params.CallNewAccountGas)
+				}
+			} else if !env.Db().Exist(address) {
 				gas.Add(gas, params.CallNewAccountGas)
 			}
 		}
-		if len(stack.data[stack.len()-3].Bytes()) > 0 {
+		if transfersValue {
 			gas.Add(gas, params.CallValueTransferGas)
 		}
 		x := calcMemSize(stack.data[stack.len()-6], stack.data[stack.len()-7])