ethereum.berlin.vm.instructions.system

Ethereum Virtual Machine (EVM) System Instructions ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

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

Introduction

Implementations of the EVM system related instructions.

generic_create

Core logic used by the CREATE* family of opcodes.

def generic_create(​evm: Evm, ​​endowment: U256, ​​contract_address: Address, ​​memory_start_position: U256, ​​memory_size: U256​) -> None:
69
    """
70
    Core logic used by the `CREATE*` family of opcodes.
71
    """
72
    # This import causes a circular import error
73
    # if it's not moved inside this method
74
    from ...vm.interpreter import STACK_DEPTH_LIMIT, process_create_message
75
76
    call_data = memory_read_bytes(
77
        evm.memory, memory_start_position, memory_size
78
    )
79
80
    create_message_gas = max_message_call_gas(Uint(evm.gas_left))
81
    evm.gas_left -= create_message_gas
82
    if evm.message.is_static:
83
        raise WriteInStaticContext
84
    evm.return_data = b""
85
86
    sender_address = evm.message.current_target
87
    sender = get_account(evm.message.block_env.state, sender_address)
88
89
    if (
90
        sender.balance < endowment
91
        or sender.nonce == Uint(2**64 - 1)
92
        or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT
93
    ):
94
        evm.gas_left += create_message_gas
95
        push(evm.stack, U256(0))
96
        return
97
98
    evm.accessed_addresses.add(contract_address)
99
100
    if account_has_code_or_nonce(
101
        evm.message.block_env.state, contract_address
102
    ) or account_has_storage(evm.message.block_env.state, contract_address):
103
        increment_nonce(
104
            evm.message.block_env.state, evm.message.current_target
105
        )
106
        push(evm.stack, U256(0))
107
        return
108
109
    increment_nonce(evm.message.block_env.state, evm.message.current_target)
110
111
    child_message = Message(
112
        block_env=evm.message.block_env,
113
        tx_env=evm.message.tx_env,
114
        caller=evm.message.current_target,
115
        target=Bytes0(),
116
        gas=create_message_gas,
117
        value=endowment,
118
        data=b"",
119
        code=call_data,
120
        current_target=contract_address,
121
        depth=evm.message.depth + Uint(1),
122
        code_address=None,
123
        should_transfer_value=True,
124
        is_static=False,
125
        accessed_addresses=evm.accessed_addresses.copy(),
126
        accessed_storage_keys=evm.accessed_storage_keys.copy(),
127
        parent_evm=evm,
128
    )
129
    child_evm = process_create_message(child_message)
130
131
    if child_evm.error:
132
        incorporate_child_on_error(evm, child_evm)
133
        evm.return_data = child_evm.output
134
        push(evm.stack, U256(0))
135
    else:
136
        incorporate_child_on_success(evm, child_evm)
137
        evm.return_data = b""
138
        push(evm.stack, U256.from_be_bytes(child_evm.message.current_target))

create

Creates a new account with associated code.

Parameters

evm : The current EVM frame.

def create(​evm: Evm​) -> None:
142
    """
143
    Creates a new account with associated code.
144
145
    Parameters
146
    ----------
147
    evm :
148
        The current EVM frame.
149
    """
150
    # STACK
151
    endowment = pop(evm.stack)
152
    memory_start_position = pop(evm.stack)
153
    memory_size = pop(evm.stack)
154
155
    # GAS
156
    extend_memory = calculate_gas_extend_memory(
157
        evm.memory, [(memory_start_position, memory_size)]
158
    )
159
160
    charge_gas(evm, GAS_CREATE + extend_memory.cost)
161
162
    # OPERATION
163
    evm.memory += b"\x00" * extend_memory.expand_by
164
    contract_address = compute_contract_address(
165
        evm.message.current_target,
166
        get_account(
167
            evm.message.block_env.state, evm.message.current_target
168
        ).nonce,
169
    )
170
171
    generic_create(
172
        evm, endowment, contract_address, memory_start_position, memory_size
173
    )
174
175
    # PROGRAM COUNTER
176
    evm.pc += Uint(1)

create2

Creates a new account with associated code.

It's similar to CREATE opcode except that the address of new account depends on the init_code instead of the nonce of sender.

Parameters

evm : The current EVM frame.

def create2(​evm: Evm​) -> None:
180
    """
181
    Creates a new account with associated code.
182
183
    It's similar to CREATE opcode except that the address of new account
184
    depends on the init_code instead of the nonce of sender.
185
186
    Parameters
187
    ----------
188
    evm :
189
        The current EVM frame.
190
    """
191
    # STACK
192
    endowment = pop(evm.stack)
193
    memory_start_position = pop(evm.stack)
194
    memory_size = pop(evm.stack)
195
    salt = pop(evm.stack).to_be_bytes32()
196
197
    # GAS
198
    extend_memory = calculate_gas_extend_memory(
199
        evm.memory, [(memory_start_position, memory_size)]
200
    )
201
    call_data_words = ceil32(Uint(memory_size)) // Uint(32)
202
    charge_gas(
203
        evm,
204
        GAS_CREATE + GAS_KECCAK256_WORD * call_data_words + extend_memory.cost,
205
    )
206
207
    # OPERATION
208
    evm.memory += b"\x00" * extend_memory.expand_by
209
    contract_address = compute_create2_contract_address(
210
        evm.message.current_target,
211
        salt,
212
        memory_read_bytes(evm.memory, memory_start_position, memory_size),
213
    )
214
215
    generic_create(
216
        evm, endowment, contract_address, memory_start_position, memory_size
217
    )
218
219
    # PROGRAM COUNTER
220
    evm.pc += Uint(1)

return_

Halts execution returning output data.

Parameters

evm : The current EVM frame.

def return_(​evm: Evm​) -> None:
224
    """
225
    Halts execution returning output data.
226
227
    Parameters
228
    ----------
229
    evm :
230
        The current EVM frame.
231
    """
232
    # STACK
233
    memory_start_position = pop(evm.stack)
234
    memory_size = pop(evm.stack)
235
236
    # GAS
237
    extend_memory = calculate_gas_extend_memory(
238
        evm.memory, [(memory_start_position, memory_size)]
239
    )
240
241
    charge_gas(evm, GAS_ZERO + extend_memory.cost)
242
243
    # OPERATION
244
    evm.memory += b"\x00" * extend_memory.expand_by
245
    evm.output = memory_read_bytes(
246
        evm.memory, memory_start_position, memory_size
247
    )
248
249
    evm.running = False
250
251
    # PROGRAM COUNTER
252
    pass

generic_call

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

def generic_call(​evm: Evm, ​​gas: Uint, ​​value: U256, ​​caller: Address, ​​to: Address, ​​code_address: Address, ​​should_transfer_value: bool, ​​is_staticcall: bool, ​​memory_input_start_position: U256, ​​memory_input_size: U256, ​​memory_output_start_position: U256, ​​memory_output_size: U256​) -> None:
269
    """
270
    Perform the core logic of the `CALL*` family of opcodes.
271
    """
272
    from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message
273
274
    evm.return_data = b""
275
276
    if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT:
277
        evm.gas_left += gas
278
        push(evm.stack, U256(0))
279
        return
280
281
    call_data = memory_read_bytes(
282
        evm.memory, memory_input_start_position, memory_input_size
283
    )
284
    code = get_account(evm.message.block_env.state, code_address).code
285
    child_message = Message(
286
        block_env=evm.message.block_env,
287
        tx_env=evm.message.tx_env,
288
        caller=caller,
289
        target=to,
290
        gas=gas,
291
        value=value,
292
        data=call_data,
293
        code=code,
294
        current_target=to,
295
        depth=evm.message.depth + Uint(1),
296
        code_address=code_address,
297
        should_transfer_value=should_transfer_value,
298
        is_static=True if is_staticcall else evm.message.is_static,
299
        accessed_addresses=evm.accessed_addresses.copy(),
300
        accessed_storage_keys=evm.accessed_storage_keys.copy(),
301
        parent_evm=evm,
302
    )
303
    child_evm = process_message(child_message)
304
305
    if child_evm.error:
306
        incorporate_child_on_error(evm, child_evm)
307
        evm.return_data = child_evm.output
308
        push(evm.stack, U256(0))
309
    else:
310
        incorporate_child_on_success(evm, child_evm)
311
        evm.return_data = child_evm.output
312
        push(evm.stack, U256(1))
313
314
    actual_output_size = min(memory_output_size, U256(len(child_evm.output)))
315
    memory_write(
316
        evm.memory,
317
        memory_output_start_position,
318
        child_evm.output[:actual_output_size],
319
    )

call

Message-call into an account.

Parameters

evm : The current EVM frame.

def call(​evm: Evm​) -> None:
323
    """
324
    Message-call into an account.
325
326
    Parameters
327
    ----------
328
    evm :
329
        The current EVM frame.
330
    """
331
    # STACK
332
    gas = Uint(pop(evm.stack))
333
    to = to_address(pop(evm.stack))
334
    value = pop(evm.stack)
335
    memory_input_start_position = pop(evm.stack)
336
    memory_input_size = pop(evm.stack)
337
    memory_output_start_position = pop(evm.stack)
338
    memory_output_size = pop(evm.stack)
339
340
    # GAS
341
    extend_memory = calculate_gas_extend_memory(
342
        evm.memory,
343
        [
344
            (memory_input_start_position, memory_input_size),
345
            (memory_output_start_position, memory_output_size),
346
        ],
347
    )
348
349
    if to in evm.accessed_addresses:
350
        access_gas_cost = GAS_WARM_ACCESS
351
    else:
352
        evm.accessed_addresses.add(to)
353
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
354
355
    code_address = to
356
357
    create_gas_cost = (
358
        Uint(0)
359
        if is_account_alive(evm.message.block_env.state, to) or value == 0
360
        else GAS_NEW_ACCOUNT
361
    )
362
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
363
    message_call_gas = calculate_message_call_gas(
364
        value,
365
        gas,
366
        Uint(evm.gas_left),
367
        extend_memory.cost,
368
        access_gas_cost + create_gas_cost + transfer_gas_cost,
369
    )
370
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
371
    if evm.message.is_static and value != U256(0):
372
        raise WriteInStaticContext
373
    evm.memory += b"\x00" * extend_memory.expand_by
374
    sender_balance = get_account(
375
        evm.message.block_env.state, evm.message.current_target
376
    ).balance
377
    if sender_balance < value:
378
        push(evm.stack, U256(0))
379
        evm.return_data = b""
380
        evm.gas_left += message_call_gas.sub_call
381
    else:
382
        generic_call(
383
            evm,
384
            message_call_gas.sub_call,
385
            value,
386
            evm.message.current_target,
387
            to,
388
            code_address,
389
            True,
390
            False,
391
            memory_input_start_position,
392
            memory_input_size,
393
            memory_output_start_position,
394
            memory_output_size,
395
        )
396
397
    # PROGRAM COUNTER
398
    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:
402
    """
403
    Message-call into this account with alternative account’s code.
404
405
    Parameters
406
    ----------
407
    evm :
408
        The current EVM frame.
409
    """
410
    # STACK
411
    gas = Uint(pop(evm.stack))
412
    code_address = to_address(pop(evm.stack))
413
    value = pop(evm.stack)
414
    memory_input_start_position = pop(evm.stack)
415
    memory_input_size = pop(evm.stack)
416
    memory_output_start_position = pop(evm.stack)
417
    memory_output_size = pop(evm.stack)
418
419
    # GAS
420
    to = evm.message.current_target
421
422
    extend_memory = calculate_gas_extend_memory(
423
        evm.memory,
424
        [
425
            (memory_input_start_position, memory_input_size),
426
            (memory_output_start_position, memory_output_size),
427
        ],
428
    )
429
430
    if code_address in evm.accessed_addresses:
431
        access_gas_cost = GAS_WARM_ACCESS
432
    else:
433
        evm.accessed_addresses.add(code_address)
434
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
435
436
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
437
    message_call_gas = calculate_message_call_gas(
438
        value,
439
        gas,
440
        Uint(evm.gas_left),
441
        extend_memory.cost,
442
        access_gas_cost + transfer_gas_cost,
443
    )
444
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
445
446
    # OPERATION
447
    evm.memory += b"\x00" * extend_memory.expand_by
448
    sender_balance = get_account(
449
        evm.message.block_env.state, evm.message.current_target
450
    ).balance
451
    if sender_balance < value:
452
        push(evm.stack, U256(0))
453
        evm.return_data = b""
454
        evm.gas_left += message_call_gas.sub_call
455
    else:
456
        generic_call(
457
            evm,
458
            message_call_gas.sub_call,
459
            value,
460
            evm.message.current_target,
461
            to,
462
            code_address,
463
            True,
464
            False,
465
            memory_input_start_position,
466
            memory_input_size,
467
            memory_output_start_position,
468
            memory_output_size,
469
        )
470
471
    # PROGRAM COUNTER
472
    evm.pc += Uint(1)

selfdestruct

Halt execution and register account for later deletion.

Parameters

evm : The current EVM frame.

def selfdestruct(​evm: Evm​) -> None:
476
    """
477
    Halt execution and register account for later deletion.
478
479
    Parameters
480
    ----------
481
    evm :
482
        The current EVM frame.
483
    """
484
    # STACK
485
    beneficiary = to_address(pop(evm.stack))
486
487
    # GAS
488
    gas_cost = GAS_SELF_DESTRUCT
489
    if beneficiary not in evm.accessed_addresses:
490
        evm.accessed_addresses.add(beneficiary)
491
        gas_cost += GAS_COLD_ACCOUNT_ACCESS
492
493
    if (
494
        not is_account_alive(evm.message.block_env.state, beneficiary)
495
        and get_account(
496
            evm.message.block_env.state, evm.message.current_target
497
        ).balance
498
        != 0
499
    ):
500
        gas_cost += GAS_SELF_DESTRUCT_NEW_ACCOUNT
501
502
    originator = evm.message.current_target
503
504
    refunded_accounts = evm.accounts_to_delete
505
    parent_evm = evm.message.parent_evm
506
    while parent_evm is not None:
507
        refunded_accounts.update(parent_evm.accounts_to_delete)
508
        parent_evm = parent_evm.message.parent_evm
509
510
    if originator not in refunded_accounts:
511
        evm.refund_counter += REFUND_SELF_DESTRUCT
512
513
    charge_gas(evm, gas_cost)
514
    if evm.message.is_static:
515
        raise WriteInStaticContext
516
517
    originator = evm.message.current_target
518
    beneficiary_balance = get_account(
519
        evm.message.block_env.state, beneficiary
520
    ).balance
521
    originator_balance = get_account(
522
        evm.message.block_env.state, originator
523
    ).balance
524
525
    # First Transfer to beneficiary
526
    set_account_balance(
527
        evm.message.block_env.state,
528
        beneficiary,
529
        beneficiary_balance + originator_balance,
530
    )
531
    # Next, Zero the balance of the address being deleted (must come after
532
    # sending to beneficiary in case the contract named itself as the
533
    # beneficiary).
534
    set_account_balance(evm.message.block_env.state, originator, U256(0))
535
536
    # register account for deletion
537
    evm.accounts_to_delete.add(originator)
538
539
    # mark beneficiary as touched
540
    if account_exists_and_is_empty(evm.message.block_env.state, beneficiary):
541
        evm.touched_accounts.add(beneficiary)
542
543
    # HALT the execution
544
    evm.running = False
545
546
    # PROGRAM COUNTER
547
    pass

delegatecall

Message-call into an account.

Parameters

evm : The current EVM frame.

def delegatecall(​evm: Evm​) -> None:
551
    """
552
    Message-call into an account.
553
554
    Parameters
555
    ----------
556
    evm :
557
        The current EVM frame.
558
    """
559
    # STACK
560
    gas = Uint(pop(evm.stack))
561
    code_address = to_address(pop(evm.stack))
562
    memory_input_start_position = pop(evm.stack)
563
    memory_input_size = pop(evm.stack)
564
    memory_output_start_position = pop(evm.stack)
565
    memory_output_size = pop(evm.stack)
566
567
    # GAS
568
    extend_memory = calculate_gas_extend_memory(
569
        evm.memory,
570
        [
571
            (memory_input_start_position, memory_input_size),
572
            (memory_output_start_position, memory_output_size),
573
        ],
574
    )
575
576
    if code_address in evm.accessed_addresses:
577
        access_gas_cost = GAS_WARM_ACCESS
578
    else:
579
        evm.accessed_addresses.add(code_address)
580
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
581
582
    message_call_gas = calculate_message_call_gas(
583
        U256(0), gas, Uint(evm.gas_left), extend_memory.cost, access_gas_cost
584
    )
585
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
586
587
    # OPERATION
588
    evm.memory += b"\x00" * extend_memory.expand_by
589
    generic_call(
590
        evm,
591
        message_call_gas.sub_call,
592
        evm.message.value,
593
        evm.message.caller,
594
        evm.message.current_target,
595
        code_address,
596
        False,
597
        False,
598
        memory_input_start_position,
599
        memory_input_size,
600
        memory_output_start_position,
601
        memory_output_size,
602
    )
603
604
    # PROGRAM COUNTER
605
    evm.pc += Uint(1)

staticcall

Message-call into an account.

Parameters

evm : The current EVM frame.

def staticcall(​evm: Evm​) -> None:
609
    """
610
    Message-call into an account.
611
612
    Parameters
613
    ----------
614
    evm :
615
        The current EVM frame.
616
    """
617
    # STACK
618
    gas = Uint(pop(evm.stack))
619
    to = to_address(pop(evm.stack))
620
    memory_input_start_position = pop(evm.stack)
621
    memory_input_size = pop(evm.stack)
622
    memory_output_start_position = pop(evm.stack)
623
    memory_output_size = pop(evm.stack)
624
625
    # GAS
626
    extend_memory = calculate_gas_extend_memory(
627
        evm.memory,
628
        [
629
            (memory_input_start_position, memory_input_size),
630
            (memory_output_start_position, memory_output_size),
631
        ],
632
    )
633
634
    if to in evm.accessed_addresses:
635
        access_gas_cost = GAS_WARM_ACCESS
636
    else:
637
        evm.accessed_addresses.add(to)
638
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
639
640
    code_address = to
641
642
    message_call_gas = calculate_message_call_gas(
643
        U256(0),
644
        gas,
645
        Uint(evm.gas_left),
646
        extend_memory.cost,
647
        access_gas_cost,
648
    )
649
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
650
651
    # OPERATION
652
    evm.memory += b"\x00" * extend_memory.expand_by
653
    generic_call(
654
        evm,
655
        message_call_gas.sub_call,
656
        U256(0),
657
        evm.message.current_target,
658
        to,
659
        code_address,
660
        True,
661
        True,
662
        memory_input_start_position,
663
        memory_input_size,
664
        memory_output_start_position,
665
        memory_output_size,
666
    )
667
668
    # PROGRAM COUNTER
669
    evm.pc += Uint(1)

revert

Stop execution and revert state changes, without consuming all provided gas and also has the ability to return a reason Parameters

evm : The current EVM frame.

def revert(​evm: Evm​) -> None:
673
    """
674
    Stop execution and revert state changes, without consuming all provided gas
675
    and also has the ability to return a reason
676
    Parameters
677
    ----------
678
    evm :
679
        The current EVM frame.
680
    """
681
    # STACK
682
    memory_start_index = pop(evm.stack)
683
    size = pop(evm.stack)
684
685
    # GAS
686
    extend_memory = calculate_gas_extend_memory(
687
        evm.memory, [(memory_start_index, size)]
688
    )
689
690
    charge_gas(evm, extend_memory.cost)
691
692
    # OPERATION
693
    evm.memory += b"\x00" * extend_memory.expand_by
694
    output = memory_read_bytes(evm.memory, memory_start_index, size)
695
    evm.output = Bytes(output)
696
    raise Revert