github.com/unicornultrafoundation/go-u2u@v1.0.0-rc1.0.20240205080301-e74a83d3fadc/evmcore/state_prefetcher.go (about)

     1  // Copyright 2015 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package evmcore
    18  
    19  import (
    20  	"sync/atomic"
    21  
    22  	"github.com/unicornultrafoundation/go-u2u/core/state"
    23  	"github.com/unicornultrafoundation/go-u2u/core/types"
    24  	"github.com/unicornultrafoundation/go-u2u/core/vm"
    25  	"github.com/unicornultrafoundation/go-u2u/params"
    26  
    27  	"github.com/unicornultrafoundation/go-u2u/utils/signers/gsignercache"
    28  )
    29  
    30  // statePrefetcher is a basic Prefetcher, which blindly executes a block on top
    31  // of an arbitrary state with the goal of prefetching potentially useful state
    32  // data from disk before the main block processor start executing.
    33  type statePrefetcher struct {
    34  	config *params.ChainConfig // Chain configuration options
    35  	bc     DummyChain          // Canonical block chain
    36  }
    37  
    38  // newStatePrefetcher initialises a new statePrefetcher.
    39  func newStatePrefetcher(config *params.ChainConfig, bc DummyChain) *statePrefetcher {
    40  	return &statePrefetcher{
    41  		config: config,
    42  		bc:     bc,
    43  	}
    44  }
    45  
    46  // Prefetch processes the state changes according to the Ethereum rules by running
    47  // the transaction messages using the statedb, but any changes are discarded. The
    48  // only goal is to pre-cache transaction signatures and state trie nodes.
    49  func (p *statePrefetcher) Prefetch(block *EvmBlock, statedb *state.StateDB, cfg vm.Config, interrupt *uint32) {
    50  	var (
    51  		header       = block.Header()
    52  		gaspool      = new(GasPool).AddGas(block.GasLimit)
    53  		blockContext = NewEVMBlockContext(header, p.bc, nil)
    54  		evm          = vm.NewEVM(blockContext, vm.TxContext{}, statedb, p.config, cfg)
    55  		signer       = gsignercache.Wrap(types.MakeSigner(p.config, header.Number))
    56  	)
    57  	// Iterate over and process the individual transactions
    58  	byzantium := p.config.IsByzantium(block.Number)
    59  	for i, tx := range block.Transactions {
    60  		// If block precaching was interrupted, abort
    61  		if interrupt != nil && atomic.LoadUint32(interrupt) == 1 {
    62  			return
    63  		}
    64  		// Convert the transaction into an executable message and pre-cache its sender
    65  		msg, err := TxAsMessage(tx, signer, header.BaseFee)
    66  		if err != nil {
    67  			return // Also invalid block, bail out
    68  		}
    69  		statedb.Prepare(tx.Hash(), i)
    70  		if err := precacheTransaction(msg, p.config, gaspool, statedb, header, evm); err != nil {
    71  			return // Ugh, something went horribly wrong, bail out
    72  		}
    73  		// If we're pre-byzantium, pre-load trie nodes for the intermediate root
    74  		if !byzantium {
    75  			statedb.IntermediateRoot(true)
    76  		}
    77  	}
    78  	// If were post-byzantium, pre-load trie nodes for the final root hash
    79  	if byzantium {
    80  		statedb.IntermediateRoot(true)
    81  	}
    82  }
    83  
    84  // precacheTransaction attempts to apply a transaction to the given state database
    85  // and uses the input parameters for its environment. The goal is not to execute
    86  // the transaction successfully, rather to warm up touched data slots.
    87  func precacheTransaction(msg types.Message, config *params.ChainConfig, gaspool *GasPool, statedb *state.StateDB, header *EvmHeader, evm *vm.EVM) error {
    88  	// Update the evm with the new transaction context.
    89  	evm.Reset(NewEVMTxContext(msg), statedb)
    90  	// Add addresses to access list if applicable
    91  	_, err := ApplyMessage(evm, msg, gaspool)
    92  	return err
    93  }