core: remove superfluous big.Int allocations

With blocks now being immutable, use big.Int values from
accessor functions instead of copying their results.

core/block_processor.go

@@ -81,9 +81,8 @@ func (self *BlockProcessor) ApplyTransaction(coinbase *state.StateObject, stated
 	// Update the state with pending changes
 	statedb.Update()
 
-	cumulative := new(big.Int).Set(usedGas.Add(usedGas, gas))
-	receipt := types.NewReceipt(statedb.Root().Bytes(), cumulative)
-
+	usedGas.Add(usedGas, gas)
+	receipt := types.NewReceipt(statedb.Root().Bytes(), usedGas)
 	logs := statedb.GetLogs(tx.Hash())
 	receipt.SetLogs(logs)
 	receipt.Bloom = types.CreateBloom(types.Receipts{receipt})
@@ -260,26 +259,28 @@ func (sm *BlockProcessor) processWithParent(block, parent *types.Block) (logs st
 	return state.Logs(), nil
 }
 
+var (
+	big8  = big.NewInt(8)
+	big32 = big.NewInt(32)
+)
+
 // AccumulateRewards credits the coinbase of the given block with the
 // mining reward. The total reward consists of the static block reward
-// and rewards for included uncles.
+// and rewards for included uncles. The coinbase of each uncle block is
+// also rewarded.
 func AccumulateRewards(statedb *state.StateDB, header *types.Header, uncles []*types.Header) {
 	reward := new(big.Int).Set(BlockReward)
-
+	r := new(big.Int)
 	for _, uncle := range uncles {
-		num := new(big.Int).Add(big.NewInt(8), uncle.Number)
-		num.Sub(num, header.Number)
-
-		r := new(big.Int)
-		r.Mul(BlockReward, num)
-		r.Div(r, big.NewInt(8))
-
+		r.Add(uncle.Number, big8)
+		r.Sub(r, header.Number)
+		r.Mul(r, BlockReward)
+		r.Div(r, big8)
 		statedb.AddBalance(uncle.Coinbase, r)
 
-		reward.Add(reward, new(big.Int).Div(BlockReward, big.NewInt(32)))
+		r.Div(BlockReward, big32)
+		reward.Add(reward, r)
 	}
-
-	// Get the account associated with the coinbase
 	statedb.AddBalance(header.Coinbase, reward)
 }
 

core/chain_manager.go

@@ -60,7 +60,9 @@ func CalcTD(block, parent *types.Block) *big.Int {
 	if parent == nil {
 		return block.Difficulty()
 	}
-	return new(big.Int).Add(parent.Td, block.Header().Difficulty)
+	d := block.Difficulty()
+	d.Add(d, parent.Td)
+	return d
 }
 
 // CalcGasLimit computes the gas limit of the next block after parent.
@@ -465,26 +467,6 @@ func (bc *ChainManager) setTotalDifficulty(td *big.Int) {
 	bc.td = new(big.Int).Set(td)
 }
 
-func (self *ChainManager) CalcTotalDiff(block *types.Block) (*big.Int, error) {
-	parent := self.GetBlock(block.Header().ParentHash)
-	if parent == nil {
-		return nil, fmt.Errorf("Unable to calculate total diff without known parent %x", block.Header().ParentHash)
-	}
-
-	parentTd := parent.Td
-
-	uncleDiff := new(big.Int)
-	for _, uncle := range block.Uncles() {
-		uncleDiff = uncleDiff.Add(uncleDiff, uncle.Difficulty)
-	}
-
-	td := new(big.Int)
-	td = td.Add(parentTd, uncleDiff)
-	td = td.Add(td, block.Header().Difficulty)
-
-	return td, nil
-}
-
 func (bc *ChainManager) Stop() {
 	close(bc.quit)
 	atomic.StoreInt32(&bc.procInterrupt, 1)

core/state_transition.go

@@ -13,10 +13,6 @@ import (
 	"github.com/ethereum/go-ethereum/params"
 )
 
-const tryJit = false
-
-var ()
-
 /*
  * The State transitioning model
  *
@@ -69,10 +65,6 @@ func MessageCreatesContract(msg Message) bool {
 	return msg.To() == nil
 }
 
-func MessageGasValue(msg Message) *big.Int {
-	return new(big.Int).Mul(msg.Gas(), msg.GasPrice())
-}
-
 // IntrinsicGas computes the 'intrisic gas' for a message
 // with the given data.
 func IntrinsicGas(data []byte) *big.Int {
@@ -104,7 +96,7 @@ func NewStateTransition(env vm.Environment, msg Message, coinbase *state.StateOb
 		env:        env,
 		msg:        msg,
 		gas:        new(big.Int),
-		gasPrice:   new(big.Int).Set(msg.GasPrice()),
+		gasPrice:   msg.GasPrice(),
 		initialGas: new(big.Int),
 		value:      msg.Value(),
 		data:       msg.Data(),
@@ -148,26 +140,22 @@ func (self *StateTransition) AddGas(amount *big.Int) {
 }
 
 func (self *StateTransition) BuyGas() error {
-	var err error
+	mgas := self.msg.Gas()
+	mgval := new(big.Int).Mul(mgas, self.gasPrice)
 
 	sender, err := self.From()
 	if err != nil {
 		return err
 	}
-	if sender.Balance().Cmp(MessageGasValue(self.msg)) < 0 {
-		return fmt.Errorf("insufficient ETH for gas (%x). Req %v, has %v", sender.Address().Bytes()[:4], MessageGasValue(self.msg), sender.Balance())
+	if sender.Balance().Cmp(mgval) < 0 {
+		return fmt.Errorf("insufficient ETH for gas (%x). Req %v, has %v", sender.Address().Bytes()[:4], mgval, sender.Balance())
 	}
-
-	coinbase := self.Coinbase()
-	err = coinbase.SubGas(self.msg.Gas(), self.msg.GasPrice())
-	if err != nil {
+	if err = self.Coinbase().SubGas(mgas, self.gasPrice); err != nil {
 		return err
 	}
-
-	self.AddGas(self.msg.Gas())
-	self.initialGas.Set(self.msg.Gas())
-	sender.SubBalance(MessageGasValue(self.msg))
-
+	self.AddGas(mgas)
+	self.initialGas.Set(mgas)
+	sender.SubBalance(mgval)
 	return nil
 }
 
@@ -245,15 +233,15 @@ func (self *StateTransition) refundGas() {
 	coinbase := self.Coinbase()
 	sender, _ := self.From() // err already checked
 	// Return remaining gas
-	remaining := new(big.Int).Mul(self.gas, self.msg.GasPrice())
+	remaining := new(big.Int).Mul(self.gas, self.gasPrice)
 	sender.AddBalance(remaining)
 
-	uhalf := new(big.Int).Div(self.gasUsed(), common.Big2)
+	uhalf := remaining.Div(self.gasUsed(), common.Big2)
 	refund := common.BigMin(uhalf, self.state.Refunds())
 	self.gas.Add(self.gas, refund)
-	self.state.AddBalance(sender.Address(), refund.Mul(refund, self.msg.GasPrice()))
+	self.state.AddBalance(sender.Address(), refund.Mul(refund, self.gasPrice))
 
-	coinbase.AddGas(self.gas, self.msg.GasPrice())
+	coinbase.AddGas(self.gas, self.gasPrice)
 }
 
 func (self *StateTransition) gasUsed() *big.Int {