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test_worst_storage_access_warm()

Documentation for tests/zkevm/test_worst_stateful_opcodes.py::test_worst_storage_access_warm@64f949d0.

Generate fixtures for these test cases for Prague with:

fill -v tests/zkevm/test_worst_stateful_opcodes.py::test_worst_storage_access_warm --fork Prague

Test running a block with as many warm storage slot accesses as possible.

Source code in tests/zkevm/test_worst_stateful_opcodes.py 
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@pytest.mark.valid_from("Cancun")
@pytest.mark.parametrize(
    "storage_action",
    [
        pytest.param(StorageAction.READ, id="SLOAD"),
        pytest.param(StorageAction.WRITE_SAME_VALUE, id="SSTORE same value"),
        pytest.param(StorageAction.WRITE_NEW_VALUE, id="SSTORE new value"),
    ],
)
@pytest.mark.slow()
def test_worst_storage_access_warm(
    blockchain_test: BlockchainTestFiller,
    pre: Alloc,
    storage_action: StorageAction,
):
    """Test running a block with as many warm storage slot accesses as possible."""
    env = Environment(gas_limit=100_000_000_000)
    attack_gas_limit = Environment().gas_limit

    blocks = []

    # The target storage slot for the warm access is storage slot 0.
    storage_slot_initial_value = 10

    # Contract code
    execution_code_body = Bytecode()
    if storage_action == StorageAction.WRITE_SAME_VALUE:
        execution_code_body = Op.SSTORE(0, Op.DUP1)
    elif storage_action == StorageAction.WRITE_NEW_VALUE:
        execution_code_body = Op.PUSH1(1) + Op.ADD + Op.SSTORE(0, Op.DUP1)
    elif storage_action == StorageAction.READ:
        execution_code_body = Op.POP(Op.SLOAD(0))

    execution_code = Op.PUSH1(storage_slot_initial_value) + While(
        body=execution_code_body,
    )
    execution_code_address = pre.deploy_contract(code=execution_code)

    creation_code = (
        Op.SSTORE(0, storage_slot_initial_value)
        + Op.EXTCODECOPY(
            address=execution_code_address,
            dest_offset=0,
            offset=0,
            size=Op.EXTCODESIZE(execution_code_address),
        )
        + Op.RETURN(0, Op.MSIZE)
    )
    sender_addr = pre.fund_eoa()
    setup_tx = Transaction(
        to=None,
        gas_limit=env.gas_limit,
        data=creation_code,
        sender=sender_addr,
    )
    blocks.append(Block(txs=[setup_tx]))

    contract_address = compute_create_address(address=sender_addr, nonce=0)

    op_tx = Transaction(
        to=contract_address,
        gas_limit=attack_gas_limit,
        sender=pre.fund_eoa(),
    )
    blocks.append(Block(txs=[op_tx]))

    blockchain_test(
        genesis_environment=env,
        pre=pre,
        post={},
        blocks=blocks,
    )

Parametrized Test Cases

The interactive table below is also available as a standalone page.

Test ID (Abbreviated) storage_action
...fork_Cancun-blockchain_test-SLOAD 1
...fork_Cancun-blockchain_test-SSTORE same value 2
...fork_Cancun-blockchain_test-SSTORE new value 3
...fork_Prague-blockchain_test-SLOAD 1
...fork_Prague-blockchain_test-SSTORE same value 2
...fork_Prague-blockchain_test-SSTORE new value 3
...fork_Osaka-blockchain_test-SLOAD 1
...fork_Osaka-blockchain_test-SSTORE same value 2
...fork_Osaka-blockchain_test-SSTORE new value 3