ethereum.shanghai.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:
68
    """
69
    Core logic used by the `CREATE*` family of opcodes.
70
    """
71
    # This import causes a circular import error
72
    # if it's not moved inside this method
73
    from ...vm.interpreter import (
74
        MAX_INIT_CODE_SIZE,
75
        STACK_DEPTH_LIMIT,
76
        process_create_message,
77
    )
78
79
    call_data = memory_read_bytes(
80
        evm.memory, memory_start_position, memory_size
81
    )
82
    if len(call_data) > MAX_INIT_CODE_SIZE:
83
        raise OutOfGasError
84
85
    create_message_gas = max_message_call_gas(Uint(evm.gas_left))
86
    evm.gas_left -= create_message_gas
87
    if evm.message.is_static:
88
        raise WriteInStaticContext
89
    evm.return_data = b""
90
91
    sender_address = evm.message.current_target
92
    sender = get_account(evm.message.block_env.state, sender_address)
93
94
    if (
95
        sender.balance < endowment
96
        or sender.nonce == Uint(2**64 - 1)
97
        or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT
98
    ):
99
        evm.gas_left += create_message_gas
100
        push(evm.stack, U256(0))
101
        return
102
103
    evm.accessed_addresses.add(contract_address)
104
105
    if account_has_code_or_nonce(
106
        evm.message.block_env.state, contract_address
107
    ) or account_has_storage(evm.message.block_env.state, contract_address):
108
        increment_nonce(
109
            evm.message.block_env.state, evm.message.current_target
110
        )
111
        push(evm.stack, U256(0))
112
        return
113
114
    increment_nonce(evm.message.block_env.state, evm.message.current_target)
115
116
    child_message = Message(
117
        block_env=evm.message.block_env,
118
        tx_env=evm.message.tx_env,
119
        caller=evm.message.current_target,
120
        target=Bytes0(),
121
        gas=create_message_gas,
122
        value=endowment,
123
        data=b"",
124
        code=call_data,
125
        current_target=contract_address,
126
        depth=evm.message.depth + Uint(1),
127
        code_address=None,
128
        should_transfer_value=True,
129
        is_static=False,
130
        accessed_addresses=evm.accessed_addresses.copy(),
131
        accessed_storage_keys=evm.accessed_storage_keys.copy(),
132
        parent_evm=evm,
133
    )
134
    child_evm = process_create_message(child_message)
135
136
    if child_evm.error:
137
        incorporate_child_on_error(evm, child_evm)
138
        evm.return_data = child_evm.output
139
        push(evm.stack, U256(0))
140
    else:
141
        incorporate_child_on_success(evm, child_evm)
142
        evm.return_data = b""
143
        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:
147
    """
148
    Creates a new account with associated code.
149
150
    Parameters
151
    ----------
152
    evm :
153
        The current EVM frame.
154
    """
155
    # STACK
156
    endowment = pop(evm.stack)
157
    memory_start_position = pop(evm.stack)
158
    memory_size = pop(evm.stack)
159
160
    # GAS
161
    extend_memory = calculate_gas_extend_memory(
162
        evm.memory, [(memory_start_position, memory_size)]
163
    )
164
    init_code_gas = init_code_cost(Uint(memory_size))
165
166
    charge_gas(evm, GAS_CREATE + extend_memory.cost + init_code_gas)
167
168
    # OPERATION
169
    evm.memory += b"\x00" * extend_memory.expand_by
170
    contract_address = compute_contract_address(
171
        evm.message.current_target,
172
        get_account(
173
            evm.message.block_env.state, evm.message.current_target
174
        ).nonce,
175
    )
176
177
    generic_create(
178
        evm,
179
        endowment,
180
        contract_address,
181
        memory_start_position,
182
        memory_size,
183
    )
184
185
    # PROGRAM COUNTER
186
    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:
190
    """
191
    Creates a new account with associated code.
192
193
    It's similar to CREATE opcode except that the address of new account
194
    depends on the init_code instead of the nonce of sender.
195
196
    Parameters
197
    ----------
198
    evm :
199
        The current EVM frame.
200
    """
201
    # STACK
202
    endowment = pop(evm.stack)
203
    memory_start_position = pop(evm.stack)
204
    memory_size = pop(evm.stack)
205
    salt = pop(evm.stack).to_be_bytes32()
206
207
    # GAS
208
    extend_memory = calculate_gas_extend_memory(
209
        evm.memory, [(memory_start_position, memory_size)]
210
    )
211
    call_data_words = ceil32(Uint(memory_size)) // Uint(32)
212
    init_code_gas = init_code_cost(Uint(memory_size))
213
    charge_gas(
214
        evm,
215
        GAS_CREATE
216
        + GAS_KECCAK256_WORD * call_data_words
217
        + extend_memory.cost
218
        + init_code_gas,
219
    )
220
221
    # OPERATION
222
    evm.memory += b"\x00" * extend_memory.expand_by
223
    contract_address = compute_create2_contract_address(
224
        evm.message.current_target,
225
        salt,
226
        memory_read_bytes(evm.memory, memory_start_position, memory_size),
227
    )
228
229
    generic_create(
230
        evm,
231
        endowment,
232
        contract_address,
233
        memory_start_position,
234
        memory_size,
235
    )
236
237
    # PROGRAM COUNTER
238
    evm.pc += Uint(1)

return_

Halts execution returning output data.

Parameters

evm : The current EVM frame.

def return_(​evm: Evm​) -> None:
242
    """
243
    Halts execution returning output data.
244
245
    Parameters
246
    ----------
247
    evm :
248
        The current EVM frame.
249
    """
250
    # STACK
251
    memory_start_position = pop(evm.stack)
252
    memory_size = pop(evm.stack)
253
254
    # GAS
255
    extend_memory = calculate_gas_extend_memory(
256
        evm.memory, [(memory_start_position, memory_size)]
257
    )
258
259
    charge_gas(evm, GAS_ZERO + extend_memory.cost)
260
261
    # OPERATION
262
    evm.memory += b"\x00" * extend_memory.expand_by
263
    evm.output = memory_read_bytes(
264
        evm.memory, memory_start_position, memory_size
265
    )
266
267
    evm.running = False
268
269
    # PROGRAM COUNTER
270
    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:
287
    """
288
    Perform the core logic of the `CALL*` family of opcodes.
289
    """
290
    from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message
291
292
    evm.return_data = b""
293
294
    if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT:
295
        evm.gas_left += gas
296
        push(evm.stack, U256(0))
297
        return
298
299
    call_data = memory_read_bytes(
300
        evm.memory, memory_input_start_position, memory_input_size
301
    )
302
    code = get_account(evm.message.block_env.state, code_address).code
303
    child_message = Message(
304
        block_env=evm.message.block_env,
305
        tx_env=evm.message.tx_env,
306
        caller=caller,
307
        target=to,
308
        gas=gas,
309
        value=value,
310
        data=call_data,
311
        code=code,
312
        current_target=to,
313
        depth=evm.message.depth + Uint(1),
314
        code_address=code_address,
315
        should_transfer_value=should_transfer_value,
316
        is_static=True if is_staticcall else evm.message.is_static,
317
        accessed_addresses=evm.accessed_addresses.copy(),
318
        accessed_storage_keys=evm.accessed_storage_keys.copy(),
319
        parent_evm=evm,
320
    )
321
    child_evm = process_message(child_message)
322
323
    if child_evm.error:
324
        incorporate_child_on_error(evm, child_evm)
325
        evm.return_data = child_evm.output
326
        push(evm.stack, U256(0))
327
    else:
328
        incorporate_child_on_success(evm, child_evm)
329
        evm.return_data = child_evm.output
330
        push(evm.stack, U256(1))
331
332
    actual_output_size = min(memory_output_size, U256(len(child_evm.output)))
333
    memory_write(
334
        evm.memory,
335
        memory_output_start_position,
336
        child_evm.output[:actual_output_size],
337
    )

call

Message-call into an account.

Parameters

evm : The current EVM frame.

def call(​evm: Evm​) -> None:
341
    """
342
    Message-call into an account.
343
344
    Parameters
345
    ----------
346
    evm :
347
        The current EVM frame.
348
    """
349
    # STACK
350
    gas = Uint(pop(evm.stack))
351
    to = to_address_masked(pop(evm.stack))
352
    value = pop(evm.stack)
353
    memory_input_start_position = pop(evm.stack)
354
    memory_input_size = pop(evm.stack)
355
    memory_output_start_position = pop(evm.stack)
356
    memory_output_size = pop(evm.stack)
357
358
    # GAS
359
    extend_memory = calculate_gas_extend_memory(
360
        evm.memory,
361
        [
362
            (memory_input_start_position, memory_input_size),
363
            (memory_output_start_position, memory_output_size),
364
        ],
365
    )
366
367
    if to in evm.accessed_addresses:
368
        access_gas_cost = GAS_WARM_ACCESS
369
    else:
370
        evm.accessed_addresses.add(to)
371
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
372
373
    code_address = to
374
375
    create_gas_cost = GAS_NEW_ACCOUNT
376
    if value == 0 or is_account_alive(evm.message.block_env.state, to):
377
        create_gas_cost = Uint(0)
378
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
379
    message_call_gas = calculate_message_call_gas(
380
        value,
381
        gas,
382
        Uint(evm.gas_left),
383
        extend_memory.cost,
384
        access_gas_cost + create_gas_cost + transfer_gas_cost,
385
    )
386
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
387
    if evm.message.is_static and value != U256(0):
388
        raise WriteInStaticContext
389
    evm.memory += b"\x00" * extend_memory.expand_by
390
    sender_balance = get_account(
391
        evm.message.block_env.state, evm.message.current_target
392
    ).balance
393
    if sender_balance < value:
394
        push(evm.stack, U256(0))
395
        evm.return_data = b""
396
        evm.gas_left += message_call_gas.sub_call
397
    else:
398
        generic_call(
399
            evm,
400
            message_call_gas.sub_call,
401
            value,
402
            evm.message.current_target,
403
            to,
404
            code_address,
405
            True,
406
            False,
407
            memory_input_start_position,
408
            memory_input_size,
409
            memory_output_start_position,
410
            memory_output_size,
411
        )
412
413
    # PROGRAM COUNTER
414
    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:
418
    """
419
    Message-call into this account with alternative account’s code.
420
421
    Parameters
422
    ----------
423
    evm :
424
        The current EVM frame.
425
    """
426
    # STACK
427
    gas = Uint(pop(evm.stack))
428
    code_address = to_address_masked(pop(evm.stack))
429
    value = pop(evm.stack)
430
    memory_input_start_position = pop(evm.stack)
431
    memory_input_size = pop(evm.stack)
432
    memory_output_start_position = pop(evm.stack)
433
    memory_output_size = pop(evm.stack)
434
435
    # GAS
436
    to = evm.message.current_target
437
438
    extend_memory = calculate_gas_extend_memory(
439
        evm.memory,
440
        [
441
            (memory_input_start_position, memory_input_size),
442
            (memory_output_start_position, memory_output_size),
443
        ],
444
    )
445
446
    if code_address in evm.accessed_addresses:
447
        access_gas_cost = GAS_WARM_ACCESS
448
    else:
449
        evm.accessed_addresses.add(code_address)
450
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
451
452
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
453
    message_call_gas = calculate_message_call_gas(
454
        value,
455
        gas,
456
        Uint(evm.gas_left),
457
        extend_memory.cost,
458
        access_gas_cost + transfer_gas_cost,
459
    )
460
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
461
462
    # OPERATION
463
    evm.memory += b"\x00" * extend_memory.expand_by
464
    sender_balance = get_account(
465
        evm.message.block_env.state, evm.message.current_target
466
    ).balance
467
    if sender_balance < value:
468
        push(evm.stack, U256(0))
469
        evm.return_data = b""
470
        evm.gas_left += message_call_gas.sub_call
471
    else:
472
        generic_call(
473
            evm,
474
            message_call_gas.sub_call,
475
            value,
476
            evm.message.current_target,
477
            to,
478
            code_address,
479
            True,
480
            False,
481
            memory_input_start_position,
482
            memory_input_size,
483
            memory_output_start_position,
484
            memory_output_size,
485
        )
486
487
    # PROGRAM COUNTER
488
    evm.pc += Uint(1)

selfdestruct

Halt execution and register account for later deletion.

Parameters

evm : The current EVM frame.

def selfdestruct(​evm: Evm​) -> None:
492
    """
493
    Halt execution and register account for later deletion.
494
495
    Parameters
496
    ----------
497
    evm :
498
        The current EVM frame.
499
    """
500
    # STACK
501
    beneficiary = to_address_masked(pop(evm.stack))
502
503
    # GAS
504
    gas_cost = GAS_SELF_DESTRUCT
505
    if beneficiary not in evm.accessed_addresses:
506
        evm.accessed_addresses.add(beneficiary)
507
        gas_cost += GAS_COLD_ACCOUNT_ACCESS
508
509
    if (
510
        not is_account_alive(evm.message.block_env.state, beneficiary)
511
        and get_account(
512
            evm.message.block_env.state, evm.message.current_target
513
        ).balance
514
        != 0
515
    ):
516
        gas_cost += GAS_SELF_DESTRUCT_NEW_ACCOUNT
517
518
    charge_gas(evm, gas_cost)
519
    if evm.message.is_static:
520
        raise WriteInStaticContext
521
522
    originator = evm.message.current_target
523
    beneficiary_balance = get_account(
524
        evm.message.block_env.state, beneficiary
525
    ).balance
526
    originator_balance = get_account(
527
        evm.message.block_env.state, originator
528
    ).balance
529
530
    # First Transfer to beneficiary
531
    set_account_balance(
532
        evm.message.block_env.state,
533
        beneficiary,
534
        beneficiary_balance + originator_balance,
535
    )
536
    # Next, Zero the balance of the address being deleted (must come after
537
    # sending to beneficiary in case the contract named itself as the
538
    # beneficiary).
539
    set_account_balance(evm.message.block_env.state, originator, U256(0))
540
541
    # register account for deletion
542
    evm.accounts_to_delete.add(originator)
543
544
    # HALT the execution
545
    evm.running = False
546
547
    # PROGRAM COUNTER
548
    pass

delegatecall

Message-call into an account.

Parameters

evm : The current EVM frame.

def delegatecall(​evm: Evm​) -> None:
552
    """
553
    Message-call into an account.
554
555
    Parameters
556
    ----------
557
    evm :
558
        The current EVM frame.
559
    """
560
    # STACK
561
    gas = Uint(pop(evm.stack))
562
    code_address = to_address_masked(pop(evm.stack))
563
    memory_input_start_position = pop(evm.stack)
564
    memory_input_size = pop(evm.stack)
565
    memory_output_start_position = pop(evm.stack)
566
    memory_output_size = pop(evm.stack)
567
568
    # GAS
569
    extend_memory = calculate_gas_extend_memory(
570
        evm.memory,
571
        [
572
            (memory_input_start_position, memory_input_size),
573
            (memory_output_start_position, memory_output_size),
574
        ],
575
    )
576
577
    if code_address in evm.accessed_addresses:
578
        access_gas_cost = GAS_WARM_ACCESS
579
    else:
580
        evm.accessed_addresses.add(code_address)
581
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
582
583
    message_call_gas = calculate_message_call_gas(
584
        U256(0), gas, Uint(evm.gas_left), extend_memory.cost, access_gas_cost
585
    )
586
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
587
588
    # OPERATION
589
    evm.memory += b"\x00" * extend_memory.expand_by
590
    generic_call(
591
        evm,
592
        message_call_gas.sub_call,
593
        evm.message.value,
594
        evm.message.caller,
595
        evm.message.current_target,
596
        code_address,
597
        False,
598
        False,
599
        memory_input_start_position,
600
        memory_input_size,
601
        memory_output_start_position,
602
        memory_output_size,
603
    )
604
605
    # PROGRAM COUNTER
606
    evm.pc += Uint(1)

staticcall

Message-call into an account.

Parameters

evm : The current EVM frame.

def staticcall(​evm: Evm​) -> None:
610
    """
611
    Message-call into an account.
612
613
    Parameters
614
    ----------
615
    evm :
616
        The current EVM frame.
617
    """
618
    # STACK
619
    gas = Uint(pop(evm.stack))
620
    to = to_address_masked(pop(evm.stack))
621
    memory_input_start_position = pop(evm.stack)
622
    memory_input_size = pop(evm.stack)
623
    memory_output_start_position = pop(evm.stack)
624
    memory_output_size = pop(evm.stack)
625
626
    # GAS
627
    extend_memory = calculate_gas_extend_memory(
628
        evm.memory,
629
        [
630
            (memory_input_start_position, memory_input_size),
631
            (memory_output_start_position, memory_output_size),
632
        ],
633
    )
634
635
    if to in evm.accessed_addresses:
636
        access_gas_cost = GAS_WARM_ACCESS
637
    else:
638
        evm.accessed_addresses.add(to)
639
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
640
641
    code_address = to
642
643
    message_call_gas = calculate_message_call_gas(
644
        U256(0),
645
        gas,
646
        Uint(evm.gas_left),
647
        extend_memory.cost,
648
        access_gas_cost,
649
    )
650
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
651
652
    # OPERATION
653
    evm.memory += b"\x00" * extend_memory.expand_by
654
    generic_call(
655
        evm,
656
        message_call_gas.sub_call,
657
        U256(0),
658
        evm.message.current_target,
659
        to,
660
        code_address,
661
        True,
662
        True,
663
        memory_input_start_position,
664
        memory_input_size,
665
        memory_output_start_position,
666
        memory_output_size,
667
    )
668
669
    # PROGRAM COUNTER
670
    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:
674
    """
675
    Stop execution and revert state changes, without consuming all provided gas
676
    and also has the ability to return a reason
677
    Parameters
678
    ----------
679
    evm :
680
        The current EVM frame.
681
    """
682
    # STACK
683
    memory_start_index = pop(evm.stack)
684
    size = pop(evm.stack)
685
686
    # GAS
687
    extend_memory = calculate_gas_extend_memory(
688
        evm.memory, [(memory_start_index, size)]
689
    )
690
691
    charge_gas(evm, extend_memory.cost)
692
693
    # OPERATION
694
    evm.memory += b"\x00" * extend_memory.expand_by
695
    output = memory_read_bytes(evm.memory, memory_start_index, size)
696
    evm.output = Bytes(output)
697
    raise Revert