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test_worst_creates_collisions()

Documentation for tests/benchmark/test_worst_bytecode.py::test_worst_creates_collisions@e9958ed2.

Generate fixtures for these test cases for Osaka with:

fill -v tests/benchmark/test_worst_bytecode.py::test_worst_creates_collisions -m benchmark

Test the CREATE and CREATE2 collisions performance.

Source code in tests/benchmark/test_worst_bytecode.py
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@pytest.mark.parametrize(
    "opcode",
    [
        Op.CREATE,
        Op.CREATE2,
    ],
)
def test_worst_creates_collisions(
    benchmark_test: BenchmarkTestFiller,
    pre: Alloc,
    fork: Fork,
    opcode: Op,
    gas_benchmark_value: int,
) -> None:
    """Test the CREATE and CREATE2 collisions performance."""
    # We deploy a "proxy contract" which is the contract that will be called in
    # a loop using all the gas in the block. This "proxy contract" is the one
    # executing CREATE2 failing with a collision. The reason why we need a
    # "proxy contract" is that CREATE(2) failing with a collision will consume
    # all the available gas. If we try to execute the CREATE(2) directly
    # without being wrapped **and capped in gas** in a previous CALL, we would
    # run out of gas very fast!
    # The proxy contract calls CREATE(2) with empty initcode. The current call
    # frame gas will be exhausted because of the collision. For this reason the
    # caller will carefully give us the minimal gas necessary to execute the
    # CREATE(2) and not waste any extra gas in the CREATE(2)-failure.
    # Note that these CREATE(2) calls will fail because in (**) below we pre-
    # alloc contracts with the same address as the ones that CREATE(2) will try
    # to create.
    proxy_contract = pre.deploy_contract(
        code=Op.CREATE2(value=Op.PUSH0, salt=Op.PUSH0, offset=Op.PUSH0, size=Op.PUSH0)
        if opcode == Op.CREATE2
        else Op.CREATE(value=Op.PUSH0, offset=Op.PUSH0, size=Op.PUSH0)
    )

    gas_costs = fork.gas_costs()
    # The CALL to the proxy contract needs at a minimum gas corresponding to
    # the CREATE(2) plus extra required PUSH0s for arguments.
    min_gas_required = gas_costs.G_CREATE + gas_costs.G_BASE * (3 if opcode == Op.CREATE else 4)
    setup = Op.PUSH20(proxy_contract) + Op.PUSH3(min_gas_required)
    attack_block = Op.POP(
        # DUP7 refers to the PUSH3 above.
        # DUP7 refers to the proxy contract address.
        Op.CALL(gas=Op.DUP7, address=Op.DUP7)
    )

    # (**) We deploy the contract that CREATE(2) will attempt to create so any
    # attempt will fail.
    if opcode == Op.CREATE2:
        addr = compute_create2_address(address=proxy_contract, salt=0, initcode=[])
        pre.deploy_contract(address=addr, code=Op.INVALID)
    else:
        # Heuristic to have an upper bound.
        max_contract_count = 2 * gas_benchmark_value // gas_costs.G_CREATE
        for nonce in range(max_contract_count):
            addr = compute_create_address(address=proxy_contract, nonce=nonce)
            pre.deploy_contract(address=addr, code=Op.INVALID)

    benchmark_test(
        code_generator=JumpLoopGenerator(setup=setup, attack_block=attack_block),
    )

Parametrized Test Cases

This test case is only parametrized by fork.

Test ID (Abbreviated) opcode
...fork_Prague-blockchain_test-opcode_CREATE CREATE
...fork_Prague-blockchain_test-opcode_CREATE2 CREATE2
...fork_Osaka-blockchain_test-opcode_CREATE CREATE
...fork_Osaka-blockchain_test-opcode_CREATE2 CREATE2