95 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			95 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
// Copyright 2019 The go-ethereum Authors
 | 
						|
// This file is part of the go-ethereum library.
 | 
						|
//
 | 
						|
// The go-ethereum library is free software: you can redistribute it and/or modify
 | 
						|
// it under the terms of the GNU Lesser General Public License as published by
 | 
						|
// the Free Software Foundation, either version 3 of the License, or
 | 
						|
// (at your option) any later version.
 | 
						|
//
 | 
						|
// The go-ethereum library is distributed in the hope that it will be useful,
 | 
						|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 | 
						|
// GNU Lesser General Public License for more details.
 | 
						|
//
 | 
						|
// You should have received a copy of the GNU Lesser General Public License
 | 
						|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
 | 
						|
 | 
						|
package core
 | 
						|
 | 
						|
import (
 | 
						|
	"sync/atomic"
 | 
						|
 | 
						|
	"github.com/ethereum/go-ethereum/consensus"
 | 
						|
	"github.com/ethereum/go-ethereum/core/state"
 | 
						|
	"github.com/ethereum/go-ethereum/core/types"
 | 
						|
	"github.com/ethereum/go-ethereum/core/vm"
 | 
						|
	"github.com/ethereum/go-ethereum/params"
 | 
						|
)
 | 
						|
 | 
						|
// statePrefetcher is a basic Prefetcher, which blindly executes a block on top
 | 
						|
// of an arbitrary state with the goal of prefetching potentially useful state
 | 
						|
// data from disk before the main block processor start executing.
 | 
						|
type statePrefetcher struct {
 | 
						|
	config *params.ChainConfig // Chain configuration options
 | 
						|
	bc     *BlockChain         // Canonical block chain
 | 
						|
	engine consensus.Engine    // Consensus engine used for block rewards
 | 
						|
}
 | 
						|
 | 
						|
// newStatePrefetcher initialises a new statePrefetcher.
 | 
						|
func newStatePrefetcher(config *params.ChainConfig, bc *BlockChain, engine consensus.Engine) *statePrefetcher {
 | 
						|
	return &statePrefetcher{
 | 
						|
		config: config,
 | 
						|
		bc:     bc,
 | 
						|
		engine: engine,
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// Prefetch processes the state changes according to the Ethereum rules by running
 | 
						|
// the transaction messages using the statedb, but any changes are discarded. The
 | 
						|
// only goal is to pre-cache transaction signatures and state trie nodes.
 | 
						|
func (p *statePrefetcher) Prefetch(block *types.Block, statedb *state.StateDB, cfg vm.Config, interrupt *uint32) {
 | 
						|
	var (
 | 
						|
		header       = block.Header()
 | 
						|
		gaspool      = new(GasPool).AddGas(block.GasLimit())
 | 
						|
		blockContext = NewEVMBlockContext(header, p.bc, nil)
 | 
						|
		evm          = vm.NewEVM(blockContext, vm.TxContext{}, statedb, p.config, cfg)
 | 
						|
		signer       = types.MakeSigner(p.config, header.Number)
 | 
						|
	)
 | 
						|
	// Iterate over and process the individual transactions
 | 
						|
	byzantium := p.config.IsByzantium(block.Number())
 | 
						|
	for i, tx := range block.Transactions() {
 | 
						|
		// If block precaching was interrupted, abort
 | 
						|
		if interrupt != nil && atomic.LoadUint32(interrupt) == 1 {
 | 
						|
			return
 | 
						|
		}
 | 
						|
		// Convert the transaction into an executable message and pre-cache its sender
 | 
						|
		msg, err := tx.AsMessage(signer, header.BaseFee)
 | 
						|
		if err != nil {
 | 
						|
			return // Also invalid block, bail out
 | 
						|
		}
 | 
						|
		statedb.Prepare(tx.Hash(), i)
 | 
						|
		if err := precacheTransaction(msg, p.config, gaspool, statedb, header, evm); err != nil {
 | 
						|
			return // Ugh, something went horribly wrong, bail out
 | 
						|
		}
 | 
						|
		// If we're pre-byzantium, pre-load trie nodes for the intermediate root
 | 
						|
		if !byzantium {
 | 
						|
			statedb.IntermediateRoot(true)
 | 
						|
		}
 | 
						|
	}
 | 
						|
	// If were post-byzantium, pre-load trie nodes for the final root hash
 | 
						|
	if byzantium {
 | 
						|
		statedb.IntermediateRoot(true)
 | 
						|
	}
 | 
						|
}
 | 
						|
 | 
						|
// precacheTransaction attempts to apply a transaction to the given state database
 | 
						|
// and uses the input parameters for its environment. The goal is not to execute
 | 
						|
// the transaction successfully, rather to warm up touched data slots.
 | 
						|
func precacheTransaction(msg types.Message, config *params.ChainConfig, gaspool *GasPool, statedb *state.StateDB, header *types.Header, evm *vm.EVM) error {
 | 
						|
	// Update the evm with the new transaction context.
 | 
						|
	evm.Reset(NewEVMTxContext(msg), statedb)
 | 
						|
	// Add addresses to access list if applicable
 | 
						|
	_, err := ApplyMessage(evm, msg, gaspool)
 | 
						|
	return err
 | 
						|
}
 |