test_stacked_storage_commit()¶

@pytest.mark.parametrize("writes_per_frame", [16, 64, 256])
def test_stacked_storage_commit(
    benchmark_test: BenchmarkTestFiller,
    pre: Alloc,
    fork: Fork,
    writes_per_frame: int,
    gas_benchmark_value: int,
    tx_gas_limit: int,
) -> None:
    """Benchmark storage writes on branching self-DELEGATECALL frames."""
    # The first frame pays a cold write per slot, so a large write set does
    # not fit in a small benchmark budget.
    first_frame_gas = writes_per_frame * fork.gas_costs().COLD_STORAGE_WRITE
    if first_frame_gas > min(tx_gas_limit, gas_benchmark_value):
        pytest.skip("write set does not fit in the transaction gas limit")

    # The second call spends the 1/64 of the gas EIP-150 withholds from the
    # first; with a single call the transaction leaves most of it unspent.
    delegate = Op.DELEGATECALL(address=Op.ADDRESS)
    writes = Bytecode()
    # Seeded slots keep every write a reset; a set costs state gas.
    storage = Storage({})
    for slot in range(writes_per_frame):
        writes += Op.SSTORE(slot, Op.GAS)
        storage[slot] = 1

    contract = pre.deploy_contract(
        writes + delegate + delegate, storage=storage
    )

    benchmark_test(
        pre=pre,
        # The frame tree stops just short of the gas limit.
        skip_gas_used_validation=True,
        verifications=[ReceiptStatusExpected()],
        tx=Transaction(to=contract, sender=pre.fund_eoa()),
    )