ethereum.forks.spurious_dragon.vm.instructions.system

Ethereum Virtual Machine (EVM) System Instructions.

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

Introduction

Implementations of the EVM system related instructions.

create

Creates a new account with associated code.

Parameters

evm : The current EVM frame.

def create(evm: Evm) -> None:
50
    <snip>
59
    # This import causes a circular import error
60
    # if it's not moved inside this method
61
    from ...vm.interpreter import STACK_DEPTH_LIMIT, process_create_message
62
63
    # STACK
64
    endowment = pop(evm.stack)
65
    memory_start_position = pop(evm.stack)
66
    memory_size = pop(evm.stack)
67
68
    # GAS
69
    extend_memory = calculate_gas_extend_memory(
70
        evm.memory, [(memory_start_position, memory_size)]
71
    )
72
73
    charge_gas(evm, GasCosts.OPCODE_CREATE_BASE + extend_memory.cost)
74
75
    create_message_gas = max_message_call_gas(Uint(evm.gas_left))
76
    evm.gas_left -= create_message_gas
77
78
    # OPERATION
79
    evm.memory += b"\x00" * extend_memory.expand_by
80
    sender_address = evm.message.current_target
81
    sender = get_account(evm.message.tx_env.state, sender_address)
82
83
    contract_address = compute_contract_address(
84
        evm.message.current_target,
85
        get_account(
86
            evm.message.tx_env.state, evm.message.current_target
87
        ).nonce,
88
    )
89
90
    if (
91
        sender.balance < endowment
92
        or sender.nonce == Uint(2**64 - 1)
93
        or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT
94
    ):
95
        push(evm.stack, U256(0))
96
        evm.gas_left += create_message_gas
97
    elif not account_deployable(evm.message.tx_env.state, contract_address):
98
        increment_nonce(evm.message.tx_env.state, evm.message.current_target)
99
        push(evm.stack, U256(0))
100
    else:
101
        call_data = memory_read_bytes(
102
            evm.memory, memory_start_position, memory_size
103
        )
104
105
        increment_nonce(evm.message.tx_env.state, evm.message.current_target)
106
107
        child_message = Message(
108
            block_env=evm.message.block_env,
109
            tx_env=evm.message.tx_env,
110
            caller=evm.message.current_target,
111
            target=Bytes0(),
112
            gas=create_message_gas,
113
            value=endowment,
114
            data=b"",
115
            code=call_data,
116
            current_target=contract_address,
117
            depth=evm.message.depth + Uint(1),
118
            code_address=None,
119
            should_transfer_value=True,
120
            parent_evm=evm,
121
        )
122
        child_evm = process_create_message(child_message)
123
124
        if child_evm.error:
125
            incorporate_child_on_error(evm, child_evm)
126
            push(evm.stack, U256(0))
127
        else:
128
            incorporate_child_on_success(evm, child_evm)
129
            push(
130
                evm.stack, U256.from_be_bytes(child_evm.message.current_target)
131
            )
132
133
    # PROGRAM COUNTER
134
    evm.pc += Uint(1)

return_

Halts execution returning output data.

Parameters

evm : The current EVM frame.

def return_(evm: Evm) -> None:
138
    <snip>
147
    # STACK
148
    memory_start_position = pop(evm.stack)
149
    memory_size = pop(evm.stack)
150
151
    # GAS
152
    extend_memory = calculate_gas_extend_memory(
153
        evm.memory, [(memory_start_position, memory_size)]
154
    )
155
156
    charge_gas(evm, GasCosts.ZERO + extend_memory.cost)
157
158
    # OPERATION
159
    evm.memory += b"\x00" * extend_memory.expand_by
160
    evm.output = memory_read_bytes(
161
        evm.memory, memory_start_position, memory_size
162
    )
163
164
    evm.running = False
165
166
    # PROGRAM COUNTER
167
    pass

GenericCall

Parameters for the core logic of the CALL* family of opcodes.

170
@final
171
@dataclass
class GenericCall:

gas

177
    gas: Uint

value

178
    value: U256

caller

179
    caller: Address

to

180
    to: Address

code_address

181
    code_address: Address

should_transfer_value

182
    should_transfer_value: bool

memory_input_start_position

183
    memory_input_start_position: U256

memory_input_size

184
    memory_input_size: U256

memory_output_start_position

185
    memory_output_start_position: U256

memory_output_size

186
    memory_output_size: U256

generic_call

Perform the core logic of the CALL* family of opcodes.

def generic_call(evm: Evm, ​​params: GenericCall) -> None:
190
    <snip>
193
    from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message
194
195
    if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT:
196
        evm.gas_left += params.gas
197
        push(evm.stack, U256(0))
198
        return
199
200
    call_data = memory_read_bytes(
201
        evm.memory,
202
        params.memory_input_start_position,
203
        params.memory_input_size,
204
    )
205
    account = get_account(evm.message.tx_env.state, params.code_address)
206
    code = get_code(evm.message.tx_env.state, account.code_hash)
207
    child_message = Message(
208
        block_env=evm.message.block_env,
209
        tx_env=evm.message.tx_env,
210
        caller=params.caller,
211
        target=params.to,
212
        gas=params.gas,
213
        value=params.value,
214
        data=call_data,
215
        code=code,
216
        current_target=params.to,
217
        depth=evm.message.depth + Uint(1),
218
        code_address=params.code_address,
219
        should_transfer_value=params.should_transfer_value,
220
        parent_evm=evm,
221
    )
222
    child_evm = process_message(child_message)
223
224
    if child_evm.error:
225
        incorporate_child_on_error(evm, child_evm)
226
        push(evm.stack, U256(0))
227
    else:
228
        incorporate_child_on_success(evm, child_evm)
229
        push(evm.stack, U256(1))
230
231
    actual_output_size = min(
232
        params.memory_output_size, U256(len(child_evm.output))
233
    )
234
    memory_write(
235
        evm.memory,
236
        params.memory_output_start_position,
237
        child_evm.output[:actual_output_size],
238
    )

call

Message-call into an account.

Parameters

evm : The current EVM frame.

def call(evm: Evm) -> None:
242
    <snip>
251
    # STACK
252
    gas = Uint(pop(evm.stack))
253
    to = to_address_masked(pop(evm.stack))
254
    value = pop(evm.stack)
255
    memory_input_start_position = pop(evm.stack)
256
    memory_input_size = pop(evm.stack)
257
    memory_output_start_position = pop(evm.stack)
258
    memory_output_size = pop(evm.stack)
259
260
    # GAS
261
    extend_memory = calculate_gas_extend_memory(
262
        evm.memory,
263
        [
264
            (memory_input_start_position, memory_input_size),
265
            (memory_output_start_position, memory_output_size),
266
        ],
267
    )
268
269
    code_address = to
270
271
    create_gas_cost = GasCosts.NEW_ACCOUNT
272
    if value == 0 or is_account_alive(evm.message.tx_env.state, to):
273
        create_gas_cost = Uint(0)
274
    transfer_gas_cost = Uint(0) if value == 0 else GasCosts.CALL_VALUE
275
    message_call_gas = calculate_message_call_gas(
276
        value,
277
        gas,
278
        Uint(evm.gas_left),
279
        memory_cost=extend_memory.cost,
280
        extra_gas=GasCosts.OPCODE_CALL_BASE
281
        + create_gas_cost
282
        + transfer_gas_cost,
283
    )
284
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
285
286
    # OPERATION
287
    evm.memory += b"\x00" * extend_memory.expand_by
288
    sender_balance = get_account(
289
        evm.message.tx_env.state, evm.message.current_target
290
    ).balance
291
    if sender_balance < value:
292
        push(evm.stack, U256(0))
293
        evm.gas_left += message_call_gas.sub_call
294
    else:
295
        generic_call(
296
            evm,
297
            GenericCall(
298
                gas=message_call_gas.sub_call,
299
                value=value,
300
                caller=evm.message.current_target,
301
                to=to,
302
                code_address=code_address,
303
                should_transfer_value=True,
304
                memory_input_start_position=memory_input_start_position,
305
                memory_input_size=memory_input_size,
306
                memory_output_start_position=memory_output_start_position,
307
                memory_output_size=memory_output_size,
308
            ),
309
        )
310
311
    # PROGRAM COUNTER
312
    evm.pc += Uint(1)

callcode

Message-call into this account with alternative account’s code.

Parameters

evm : The current EVM frame.

def callcode(evm: Evm) -> None:
316
    <snip>
325
    # STACK
326
    gas = Uint(pop(evm.stack))
327
    code_address = to_address_masked(pop(evm.stack))
328
    value = pop(evm.stack)
329
    memory_input_start_position = pop(evm.stack)
330
    memory_input_size = pop(evm.stack)
331
    memory_output_start_position = pop(evm.stack)
332
    memory_output_size = pop(evm.stack)
333
334
    # GAS
335
    to = evm.message.current_target
336
337
    extend_memory = calculate_gas_extend_memory(
338
        evm.memory,
339
        [
340
            (memory_input_start_position, memory_input_size),
341
            (memory_output_start_position, memory_output_size),
342
        ],
343
    )
344
    transfer_gas_cost = Uint(0) if value == 0 else GasCosts.CALL_VALUE
345
    message_call_gas = calculate_message_call_gas(
346
        value,
347
        gas,
348
        Uint(evm.gas_left),
349
        extend_memory.cost,
350
        GasCosts.OPCODE_CALL_BASE + transfer_gas_cost,
351
    )
352
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
353
354
    # OPERATION
355
    evm.memory += b"\x00" * extend_memory.expand_by
356
    sender_balance = get_account(
357
        evm.message.tx_env.state, evm.message.current_target
358
    ).balance
359
    if sender_balance < value:
360
        push(evm.stack, U256(0))
361
        evm.gas_left += message_call_gas.sub_call
362
    else:
363
        generic_call(
364
            evm,
365
            GenericCall(
366
                gas=message_call_gas.sub_call,
367
                value=value,
368
                caller=evm.message.current_target,
369
                to=to,
370
                code_address=code_address,
371
                should_transfer_value=True,
372
                memory_input_start_position=memory_input_start_position,
373
                memory_input_size=memory_input_size,
374
                memory_output_start_position=memory_output_start_position,
375
                memory_output_size=memory_output_size,
376
            ),
377
        )
378
379
    # PROGRAM COUNTER
380
    evm.pc += Uint(1)

selfdestruct

Halt execution and register account for later deletion.

Parameters

evm : The current EVM frame.

def selfdestruct(evm: Evm) -> None:
384
    <snip>
393
    # STACK
394
    beneficiary = to_address_masked(pop(evm.stack))
395
396
    # GAS
397
    gas_cost = GasCosts.OPCODE_SELFDESTRUCT_BASE
398
    if (
399
        not is_account_alive(evm.message.tx_env.state, beneficiary)
400
        and get_account(
401
            evm.message.tx_env.state, evm.message.current_target
402
        ).balance
403
        != 0
404
    ):
405
        gas_cost += GasCosts.OPCODE_SELFDESTRUCT_NEW_ACCOUNT
406
407
    originator = evm.message.current_target
408
409
    refunded_accounts = evm.accounts_to_delete
410
    parent_evm = evm.message.parent_evm
411
    while parent_evm is not None:
412
        refunded_accounts.update(parent_evm.accounts_to_delete)
413
        parent_evm = parent_evm.message.parent_evm
414
415
    if originator not in refunded_accounts:
416
        evm.refund_counter += GasCosts.REFUND_SELF_DESTRUCT
417
418
    charge_gas(evm, gas_cost)
419
420
    beneficiary_balance = get_account(
421
        evm.message.tx_env.state, beneficiary
422
    ).balance
423
    originator_balance = get_account(
424
        evm.message.tx_env.state, originator
425
    ).balance
426
427
    # First Transfer to beneficiary
428
    set_account_balance(
429
        evm.message.tx_env.state,
430
        beneficiary,
431
        beneficiary_balance + originator_balance,
432
    )
433
    # Next, Zero the balance of the address being deleted (must come after
434
    # sending to beneficiary in case the contract named itself as the
435
    # beneficiary).
436
    set_account_balance(evm.message.tx_env.state, originator, U256(0))
437
438
    # register account for deletion
439
    evm.accounts_to_delete.add(originator)
440
441
    # mark beneficiary as touched
442
    if account_exists_and_is_empty(evm.message.tx_env.state, beneficiary):
443
        evm.touched_accounts.add(beneficiary)
444
445
    # HALT the execution
446
    evm.running = False
447
448
    # PROGRAM COUNTER
449
    pass

delegatecall

Message-call into an account.

Parameters

evm : The current EVM frame.

def delegatecall(evm: Evm) -> None:
453
    <snip>
462
    # STACK
463
    gas = Uint(pop(evm.stack))
464
    code_address = to_address_masked(pop(evm.stack))
465
    memory_input_start_position = pop(evm.stack)
466
    memory_input_size = pop(evm.stack)
467
    memory_output_start_position = pop(evm.stack)
468
    memory_output_size = pop(evm.stack)
469
470
    # GAS
471
    extend_memory = calculate_gas_extend_memory(
472
        evm.memory,
473
        [
474
            (memory_input_start_position, memory_input_size),
475
            (memory_output_start_position, memory_output_size),
476
        ],
477
    )
478
    message_call_gas = calculate_message_call_gas(
479
        U256(0),
480
        gas,
481
        Uint(evm.gas_left),
482
        extend_memory.cost,
483
        GasCosts.OPCODE_CALL_BASE,
484
    )
485
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
486
487
    # OPERATION
488
    evm.memory += b"\x00" * extend_memory.expand_by
489
    generic_call(
490
        evm,
491
        GenericCall(
492
            gas=message_call_gas.sub_call,
493
            value=evm.message.value,
494
            caller=evm.message.caller,
495
            to=evm.message.current_target,
496
            code_address=code_address,
497
            should_transfer_value=False,
498
            memory_input_start_position=memory_input_start_position,
499
            memory_input_size=memory_input_size,
500
            memory_output_start_position=memory_output_start_position,
501
            memory_output_size=memory_output_size,
502
        ),
503
    )
504
505
    # PROGRAM COUNTER
506
    evm.pc += Uint(1)