core/vm: precompiles into interpreter, 0-size alloc intpool,prealloc receipts

core/state_processor.go

@@ -66,13 +66,14 @@ func (p *StateProcessor) Process(block *types.Block, statedb *state.StateDB, cfg
 		misc.ApplyDAOHardFork(statedb)
 	}
 	// Iterate over and process the individual transactions
+	receipts = make([]*types.Receipt, len(block.Transactions()))
 	for i, tx := range block.Transactions() {
 		statedb.Prepare(tx.Hash(), block.Hash(), i)
 		receipt, _, err := ApplyTransaction(p.config, p.bc, nil, gp, statedb, header, tx, usedGas, cfg)
 		if err != nil {
 			return nil, nil, 0, err
 		}
-		receipts = append(receipts, receipt)
+		receipts[i] = receipt
 		allLogs = append(allLogs, receipt.Logs...)
 	}
 	// Finalize the block, applying any consensus engine specific extras (e.g. block rewards)

core/vm/evm.go

@@ -41,11 +41,7 @@ type (
 // run runs the given contract and takes care of running precompiles with a fallback to the byte code interpreter.
 func run(evm *EVM, contract *Contract, input []byte) ([]byte, error) {
 	if contract.CodeAddr != nil {
-		precompiles := PrecompiledContractsHomestead
-		if evm.ChainConfig().IsByzantium(evm.BlockNumber) {
-			precompiles = PrecompiledContractsByzantium
-		}
-		if p := precompiles[*contract.CodeAddr]; p != nil {
+		if p := evm.interpreter.precompiles[*contract.CodeAddr]; p != nil {
 			return RunPrecompiledContract(p, input, contract)
 		}
 	}
@@ -155,11 +151,8 @@ func (evm *EVM) Call(caller ContractRef, addr common.Address, input []byte, gas
 		snapshot = evm.StateDB.Snapshot()
 	)
 	if !evm.StateDB.Exist(addr) {
-		precompiles := PrecompiledContractsHomestead
-		if evm.ChainConfig().IsByzantium(evm.BlockNumber) {
-			precompiles = PrecompiledContractsByzantium
-		}
-		if precompiles[addr] == nil && evm.ChainConfig().IsEIP158(evm.BlockNumber) && value.Sign() == 0 {
+		if evm.interpreter.precompiles[addr] == nil && evm.ChainConfig().IsEIP158(evm.BlockNumber) && value.Sign() == 0 {
+
 			// Calling a non existing account, don't do antything, but ping the tracer
 			if evm.vmConfig.Debug && evm.depth == 0 {
 				evm.vmConfig.Tracer.CaptureStart(caller.Address(), addr, false, input, gas, value)
@@ -171,10 +164,21 @@ func (evm *EVM) Call(caller ContractRef, addr common.Address, input []byte, gas
 	}
 	evm.Transfer(evm.StateDB, caller.Address(), to.Address(), value)
 
+	code := evm.StateDB.GetCode(addr)
+	codeHash := evm.StateDB.GetCodeHash(addr)
+	_, isPrecompile := evm.interpreter.precompiles[addr]
+
+	if !isPrecompile && len(code) == 0 {
+		// Shortcut execution if there is no code,
+		// but make sure to set returndata to nil
+		evm.interpreter.returnData = nil
+		return nil, gas, nil
+	}
+
 	// Initialise a new contract and set the code that is to be used by the EVM.
 	// The contract is a scoped environment for this execution context only.
 	contract := NewContract(caller, to, value, gas)
-	contract.SetCallCode(&addr, evm.StateDB.GetCodeHash(addr), evm.StateDB.GetCode(addr))
+	contract.SetCallCode(&addr, codeHash, code)
 
 	start := time.Now()
 

core/vm/interpreter.go

@@ -20,6 +20,7 @@ import (
 	"fmt"
 	"sync/atomic"
 
+	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/math"
 	"github.com/ethereum/go-ethereum/params"
 )
@@ -53,6 +54,7 @@ type Interpreter struct {
 
 	readOnly    bool   // Whether to throw on stateful modifications
 	returnData  []byte // Last CALL's return data for subsequent reuse
+	precompiles map[common.Address]PrecompiledContract
 }
 
 // NewInterpreter returns a new instance of the Interpreter.
@@ -73,11 +75,17 @@ func NewInterpreter(evm *EVM, cfg Config) *Interpreter {
 		}
 	}
 
+	precompiles := PrecompiledContractsHomestead
+	if evm.ChainConfig().IsByzantium(evm.BlockNumber) {
+		precompiles = PrecompiledContractsByzantium
+	}
+
 	return &Interpreter{
 		evm:         evm,
 		cfg:         cfg,
 		gasTable:    evm.ChainConfig().GasTable(evm.BlockNumber),
-		intPool:  newIntPool(),
+		intPool:     newZerosizeIntPool(),
+		precompiles: precompiles,
 	}
 }
 

core/vm/intpool.go

@@ -32,6 +32,10 @@ func newIntPool() *intPool {
 	return &intPool{pool: newstack()}
 }
 
+func newZerosizeIntPool() *intPool {
+	return &intPool{pool: newZeroSizeStack()}
+}
+
 // get retrieves a big int from the pool, allocating one if the pool is empty.
 // Note, the returned int's value is arbitrary and will not be zeroed!
 func (p *intPool) get() *big.Int {

core/vm/stack.go

@@ -32,6 +32,10 @@ func newstack() *Stack {
 	return &Stack{data: make([]*big.Int, 0, 1024)}
 }
 
+func newZeroSizeStack() *Stack {
+	return &Stack{data: make([]*big.Int, 0)}
+}
+
 func (st *Stack) Data() []*big.Int {
 	return st.data
 }