ethereum.homestead.vmethereum.dao_fork.vm

Ethereum Virtual Machine (EVM) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

.. contents:: Table of Contents :backlinks: none :local:

Introduction

The abstract computer which runs the code stored in an .fork_types.Account.

__all__

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__all__ = ("Environment", "Evm", "Message")

BlockEnvironment

Items external to the virtual machine itself, provided by the environment.

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@dataclass
class BlockEnvironment:

chain_id

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    chain_id: U64

state

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    state: State

block_gas_limit

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    block_gas_limit: Uint

block_hashes

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    block_hashes: List[Hash32]

coinbase

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    coinbase: Address

number

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    number: Uint

time

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    time: U256

difficulty

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    difficulty: Uint

BlockOutput

Output from applying the block body to the present state.

Contains the following:

block_gas_used : ethereum.base_types.Uint Gas used for executing all transactions. transactions_trie : ethereum.fork_types.Root Trie of all the transactions in the block. receipts_trie : ethereum.fork_types.Root Trie root of all the receipts in the block. receipt_keys : Key of all the receipts in the block. block_logs : Bloom Logs bloom of all the logs included in all the transactions of the block.

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@dataclass
class BlockOutput:

block_gas_used

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    block_gas_used: Uint = Uint(0)

transactions_trie

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    transactions_trie: Trie[Bytes, Optional[Transaction]] = field(
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        default_factory=lambda: Trie(secured=False, default=None)
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    )

receipts_trie

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    receipts_trie: Trie[Bytes, Optional[Receipt]] = field(
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        default_factory=lambda: Trie(secured=False, default=None)
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    )

receipt_keys

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    receipt_keys: Tuple[Bytes, ...] = field(default_factory=tuple)

block_logs

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    block_logs: Tuple[Log, ...] = field(default_factory=tuple)

TransactionEnvironment

Items that are used by contract creation or message call.

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@dataclass
class TransactionEnvironment:

origin

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    origin: Address

gas_price

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    gas_price: Uint

gas

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    gas: Uint

index_in_block

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    index_in_block: Uint

tx_hash

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    tx_hash: Optional[Hash32]

traces

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    traces: List[dict]

Message

Items that are used by contract creation or message call.

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@dataclass
class Message:

block_env

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    block_env: BlockEnvironment

tx_env

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    tx_env: TransactionEnvironment

caller

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    caller: Address

target

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    target: Union[Bytes0, Address]

current_target

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    current_target: Address

gas

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    gas: Uint

value

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    value: U256

data

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    data: Bytes

code_address

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    code_address: Optional[Address]

code

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    code: Bytes

depth

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    depth: Uint

should_transfer_value

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    should_transfer_value: bool

parent_evm

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    parent_evm: Optional["Evm"]

Evm

The internal state of the virtual machine.

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@dataclass
class Evm:

pc

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    pc: Uint

stack

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    stack: List[U256]

memory

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    memory: bytearray

code

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    code: Bytes

gas_left

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    gas_left: Uint

valid_jump_destinations

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    valid_jump_destinations: Set[Uint]

logs

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    logs: Tuple[Log, ...]

refund_counter

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    refund_counter: int

running

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    running: bool

message

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    message: Message

output

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    output: Bytes

accounts_to_delete

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    accounts_to_delete: Set[Address]

error

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    error: Optional[EthereumException]

incorporate_child_on_success

Incorporate the state of a successful child_evm into the parent evm.

Parameters

evm : The parent EVM. child_evm : The child evm to incorporate.

def incorporate_child_on_success(​evm: Evm, ​​child_evm: Evm​) -> None:
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    """
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    Incorporate the state of a successful `child_evm` into the parent `evm`.
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    Parameters
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    ----------
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    evm :
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        The parent `EVM`.
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    child_evm :
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        The child evm to incorporate.
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    """
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    evm.gas_left += child_evm.gas_left
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    evm.logs += child_evm.logs
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    evm.refund_counter += child_evm.refund_counter
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    evm.accounts_to_delete.update(child_evm.accounts_to_delete)

incorporate_child_on_error

Incorporate the state of an unsuccessful child_evm into the parent evm.

Parameters

evm : The parent EVM. child_evm : The child evm to incorporate.

def incorporate_child_on_error(​evm: Evm, ​​child_evm: Evm​) -> None:
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    """
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    Incorporate the state of an unsuccessful `child_evm` into the parent `evm`.
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    Parameters
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    ----------
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    evm :
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        The parent `EVM`.
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    child_evm :
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        The child evm to incorporate.
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    """
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    evm.gas_left += child_evm.gas_left