ethereum.cancun.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, ​​init_code_gas: Uint​) -> 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 (
75
        MAX_CODE_SIZE,
76
        STACK_DEPTH_LIMIT,
77
        process_create_message,
78
    )
79
80
    call_data = memory_read_bytes(
81
        evm.memory, memory_start_position, memory_size
82
    )
83
    if len(call_data) > 2 * MAX_CODE_SIZE:
84
        raise OutOfGasError
85
86
    evm.accessed_addresses.add(contract_address)
87
88
    create_message_gas = max_message_call_gas(Uint(evm.gas_left))
89
    evm.gas_left -= create_message_gas
90
    if evm.message.is_static:
91
        raise WriteInStaticContext
92
    evm.return_data = b""
93
94
    sender_address = evm.message.current_target
95
    sender = get_account(evm.env.state, sender_address)
96
97
    if (
98
        sender.balance < endowment
99
        or sender.nonce == Uint(2**64 - 1)
100
        or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT
101
    ):
102
        evm.gas_left += create_message_gas
103
        push(evm.stack, U256(0))
104
        return
105
106
    if account_has_code_or_nonce(evm.env.state, contract_address):
107
        increment_nonce(evm.env.state, evm.message.current_target)
108
        push(evm.stack, U256(0))
109
        return
110
111
    increment_nonce(evm.env.state, evm.message.current_target)
112
113
    child_message = Message(
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, evm.env)
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
    init_code_gas = init_code_cost(Uint(memory_size))
160
161
    charge_gas(evm, GAS_CREATE + extend_memory.cost + init_code_gas)
162
163
    # OPERATION
164
    evm.memory += b"\x00" * extend_memory.expand_by
165
    contract_address = compute_contract_address(
166
        evm.message.current_target,
167
        get_account(evm.env.state, evm.message.current_target).nonce,
168
    )
169
170
    generic_create(
171
        evm,
172
        endowment,
173
        contract_address,
174
        memory_start_position,
175
        memory_size,
176
        init_code_gas,
177
    )
178
179
    # PROGRAM COUNTER
180
    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:
184
    """
185
    Creates a new account with associated code.
186
187
    It's similar to CREATE opcode except that the address of new account
188
    depends on the init_code instead of the nonce of sender.
189
190
    Parameters
191
    ----------
192
    evm :
193
        The current EVM frame.
194
    """
195
    # STACK
196
    endowment = pop(evm.stack)
197
    memory_start_position = pop(evm.stack)
198
    memory_size = pop(evm.stack)
199
    salt = pop(evm.stack).to_be_bytes32()
200
201
    # GAS
202
    extend_memory = calculate_gas_extend_memory(
203
        evm.memory, [(memory_start_position, memory_size)]
204
    )
205
    call_data_words = ceil32(Uint(memory_size)) // Uint(32)
206
    init_code_gas = init_code_cost(Uint(memory_size))
207
    charge_gas(
208
        evm,
209
        GAS_CREATE
210
        + GAS_KECCAK256_WORD * call_data_words
211
        + extend_memory.cost
212
        + init_code_gas,
213
    )
214
215
    # OPERATION
216
    evm.memory += b"\x00" * extend_memory.expand_by
217
    contract_address = compute_create2_contract_address(
218
        evm.message.current_target,
219
        salt,
220
        memory_read_bytes(evm.memory, memory_start_position, memory_size),
221
    )
222
223
    generic_create(
224
        evm,
225
        endowment,
226
        contract_address,
227
        memory_start_position,
228
        memory_size,
229
        init_code_gas,
230
    )
231
232
    # PROGRAM COUNTER
233
    evm.pc += Uint(1)

return_

Halts execution returning output data.

Parameters

evm : The current EVM frame.

def return_(​evm: Evm​) -> None:
237
    """
238
    Halts execution returning output data.
239
240
    Parameters
241
    ----------
242
    evm :
243
        The current EVM frame.
244
    """
245
    # STACK
246
    memory_start_position = pop(evm.stack)
247
    memory_size = pop(evm.stack)
248
249
    # GAS
250
    extend_memory = calculate_gas_extend_memory(
251
        evm.memory, [(memory_start_position, memory_size)]
252
    )
253
254
    charge_gas(evm, GAS_ZERO + extend_memory.cost)
255
256
    # OPERATION
257
    evm.memory += b"\x00" * extend_memory.expand_by
258
    evm.output = memory_read_bytes(
259
        evm.memory, memory_start_position, memory_size
260
    )
261
262
    evm.running = False
263
264
    # PROGRAM COUNTER
265
    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:
282
    """
283
    Perform the core logic of the `CALL*` family of opcodes.
284
    """
285
    from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message
286
287
    evm.return_data = b""
288
289
    if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT:
290
        evm.gas_left += gas
291
        push(evm.stack, U256(0))
292
        return
293
294
    call_data = memory_read_bytes(
295
        evm.memory, memory_input_start_position, memory_input_size
296
    )
297
    code = get_account(evm.env.state, code_address).code
298
    child_message = Message(
299
        caller=caller,
300
        target=to,
301
        gas=gas,
302
        value=value,
303
        data=call_data,
304
        code=code,
305
        current_target=to,
306
        depth=evm.message.depth + Uint(1),
307
        code_address=code_address,
308
        should_transfer_value=should_transfer_value,
309
        is_static=True if is_staticcall else evm.message.is_static,
310
        accessed_addresses=evm.accessed_addresses.copy(),
311
        accessed_storage_keys=evm.accessed_storage_keys.copy(),
312
        parent_evm=evm,
313
    )
314
    child_evm = process_message(child_message, evm.env)
315
316
    if child_evm.error:
317
        incorporate_child_on_error(evm, child_evm)
318
        evm.return_data = child_evm.output
319
        push(evm.stack, U256(0))
320
    else:
321
        incorporate_child_on_success(evm, child_evm)
322
        evm.return_data = child_evm.output
323
        push(evm.stack, U256(1))
324
325
    actual_output_size = min(memory_output_size, U256(len(child_evm.output)))
326
    memory_write(
327
        evm.memory,
328
        memory_output_start_position,
329
        child_evm.output[:actual_output_size],
330
    )

call

Message-call into an account.

Parameters

evm : The current EVM frame.

def call(​evm: Evm​) -> None:
334
    """
335
    Message-call into an account.
336
337
    Parameters
338
    ----------
339
    evm :
340
        The current EVM frame.
341
    """
342
    # STACK
343
    gas = Uint(pop(evm.stack))
344
    to = to_address(pop(evm.stack))
345
    value = pop(evm.stack)
346
    memory_input_start_position = pop(evm.stack)
347
    memory_input_size = pop(evm.stack)
348
    memory_output_start_position = pop(evm.stack)
349
    memory_output_size = pop(evm.stack)
350
351
    # GAS
352
    extend_memory = calculate_gas_extend_memory(
353
        evm.memory,
354
        [
355
            (memory_input_start_position, memory_input_size),
356
            (memory_output_start_position, memory_output_size),
357
        ],
358
    )
359
360
    if to in evm.accessed_addresses:
361
        access_gas_cost = GAS_WARM_ACCESS
362
    else:
363
        evm.accessed_addresses.add(to)
364
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
365
366
    create_gas_cost = (
367
        Uint(0)
368
        if is_account_alive(evm.env.state, to) or value == 0
369
        else GAS_NEW_ACCOUNT
370
    )
371
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
372
    message_call_gas = calculate_message_call_gas(
373
        value,
374
        gas,
375
        Uint(evm.gas_left),
376
        extend_memory.cost,
377
        access_gas_cost + create_gas_cost + transfer_gas_cost,
378
    )
379
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
380
    if evm.message.is_static and value != U256(0):
381
        raise WriteInStaticContext
382
    evm.memory += b"\x00" * extend_memory.expand_by
383
    sender_balance = get_account(
384
        evm.env.state, evm.message.current_target
385
    ).balance
386
    if sender_balance < value:
387
        push(evm.stack, U256(0))
388
        evm.return_data = b""
389
        evm.gas_left += message_call_gas.stipend
390
    else:
391
        generic_call(
392
            evm,
393
            message_call_gas.stipend,
394
            value,
395
            evm.message.current_target,
396
            to,
397
            to,
398
            True,
399
            False,
400
            memory_input_start_position,
401
            memory_input_size,
402
            memory_output_start_position,
403
            memory_output_size,
404
        )
405
406
    # PROGRAM COUNTER
407
    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:
411
    """
412
    Message-call into this account with alternative account’s code.
413
414
    Parameters
415
    ----------
416
    evm :
417
        The current EVM frame.
418
    """
419
    # STACK
420
    gas = Uint(pop(evm.stack))
421
    code_address = to_address(pop(evm.stack))
422
    value = pop(evm.stack)
423
    memory_input_start_position = pop(evm.stack)
424
    memory_input_size = pop(evm.stack)
425
    memory_output_start_position = pop(evm.stack)
426
    memory_output_size = pop(evm.stack)
427
428
    # GAS
429
    to = evm.message.current_target
430
431
    extend_memory = calculate_gas_extend_memory(
432
        evm.memory,
433
        [
434
            (memory_input_start_position, memory_input_size),
435
            (memory_output_start_position, memory_output_size),
436
        ],
437
    )
438
439
    if code_address in evm.accessed_addresses:
440
        access_gas_cost = GAS_WARM_ACCESS
441
    else:
442
        evm.accessed_addresses.add(code_address)
443
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
444
445
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
446
    message_call_gas = calculate_message_call_gas(
447
        value,
448
        gas,
449
        Uint(evm.gas_left),
450
        extend_memory.cost,
451
        access_gas_cost + transfer_gas_cost,
452
    )
453
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
454
455
    # OPERATION
456
    evm.memory += b"\x00" * extend_memory.expand_by
457
    sender_balance = get_account(
458
        evm.env.state, evm.message.current_target
459
    ).balance
460
    if sender_balance < value:
461
        push(evm.stack, U256(0))
462
        evm.return_data = b""
463
        evm.gas_left += message_call_gas.stipend
464
    else:
465
        generic_call(
466
            evm,
467
            message_call_gas.stipend,
468
            value,
469
            evm.message.current_target,
470
            to,
471
            code_address,
472
            True,
473
            False,
474
            memory_input_start_position,
475
            memory_input_size,
476
            memory_output_start_position,
477
            memory_output_size,
478
        )
479
480
    # PROGRAM COUNTER
481
    evm.pc += Uint(1)

selfdestruct

Halt execution and register account for later deletion.

Parameters

evm : The current EVM frame.

def selfdestruct(​evm: Evm​) -> None:
485
    """
486
    Halt execution and register account for later deletion.
487
488
    Parameters
489
    ----------
490
    evm :
491
        The current EVM frame.
492
    """
493
    # STACK
494
    beneficiary = to_address(pop(evm.stack))
495
496
    # GAS
497
    gas_cost = GAS_SELF_DESTRUCT
498
    if beneficiary not in evm.accessed_addresses:
499
        evm.accessed_addresses.add(beneficiary)
500
        gas_cost += GAS_COLD_ACCOUNT_ACCESS
501
502
    if (
503
        not is_account_alive(evm.env.state, beneficiary)
504
        and get_account(evm.env.state, evm.message.current_target).balance != 0
505
    ):
506
        gas_cost += GAS_SELF_DESTRUCT_NEW_ACCOUNT
507
508
    charge_gas(evm, gas_cost)
509
    if evm.message.is_static:
510
        raise WriteInStaticContext
511
512
    originator = evm.message.current_target
513
    originator_balance = get_account(evm.env.state, originator).balance
514
515
    move_ether(
516
        evm.env.state,
517
        originator,
518
        beneficiary,
519
        originator_balance,
520
    )
521
522
    # register account for deletion only if it was created
523
    # in the same transaction
524
    if originator in evm.env.state.created_accounts:
525
        # If beneficiary is the same as originator, then
526
        # the ether is burnt.
527
        set_account_balance(evm.env.state, originator, U256(0))
528
        evm.accounts_to_delete.add(originator)
529
530
    # mark beneficiary as touched
531
    if account_exists_and_is_empty(evm.env.state, beneficiary):
532
        evm.touched_accounts.add(beneficiary)
533
534
    # HALT the execution
535
    evm.running = False
536
537
    # PROGRAM COUNTER
538
    pass

delegatecall

Message-call into an account.

Parameters

evm : The current EVM frame.

def delegatecall(​evm: Evm​) -> None:
542
    """
543
    Message-call into an account.
544
545
    Parameters
546
    ----------
547
    evm :
548
        The current EVM frame.
549
    """
550
    # STACK
551
    gas = Uint(pop(evm.stack))
552
    code_address = to_address(pop(evm.stack))
553
    memory_input_start_position = pop(evm.stack)
554
    memory_input_size = pop(evm.stack)
555
    memory_output_start_position = pop(evm.stack)
556
    memory_output_size = pop(evm.stack)
557
558
    # GAS
559
    extend_memory = calculate_gas_extend_memory(
560
        evm.memory,
561
        [
562
            (memory_input_start_position, memory_input_size),
563
            (memory_output_start_position, memory_output_size),
564
        ],
565
    )
566
567
    if code_address in evm.accessed_addresses:
568
        access_gas_cost = GAS_WARM_ACCESS
569
    else:
570
        evm.accessed_addresses.add(code_address)
571
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
572
573
    message_call_gas = calculate_message_call_gas(
574
        U256(0), gas, Uint(evm.gas_left), extend_memory.cost, access_gas_cost
575
    )
576
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
577
578
    # OPERATION
579
    evm.memory += b"\x00" * extend_memory.expand_by
580
    generic_call(
581
        evm,
582
        message_call_gas.stipend,
583
        evm.message.value,
584
        evm.message.caller,
585
        evm.message.current_target,
586
        code_address,
587
        False,
588
        False,
589
        memory_input_start_position,
590
        memory_input_size,
591
        memory_output_start_position,
592
        memory_output_size,
593
    )
594
595
    # PROGRAM COUNTER
596
    evm.pc += Uint(1)

staticcall

Message-call into an account.

Parameters

evm : The current EVM frame.

def staticcall(​evm: Evm​) -> None:
600
    """
601
    Message-call into an account.
602
603
    Parameters
604
    ----------
605
    evm :
606
        The current EVM frame.
607
    """
608
    # STACK
609
    gas = Uint(pop(evm.stack))
610
    to = to_address(pop(evm.stack))
611
    memory_input_start_position = pop(evm.stack)
612
    memory_input_size = pop(evm.stack)
613
    memory_output_start_position = pop(evm.stack)
614
    memory_output_size = pop(evm.stack)
615
616
    # GAS
617
    extend_memory = calculate_gas_extend_memory(
618
        evm.memory,
619
        [
620
            (memory_input_start_position, memory_input_size),
621
            (memory_output_start_position, memory_output_size),
622
        ],
623
    )
624
625
    if to in evm.accessed_addresses:
626
        access_gas_cost = GAS_WARM_ACCESS
627
    else:
628
        evm.accessed_addresses.add(to)
629
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
630
631
    message_call_gas = calculate_message_call_gas(
632
        U256(0),
633
        gas,
634
        Uint(evm.gas_left),
635
        extend_memory.cost,
636
        access_gas_cost,
637
    )
638
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
639
640
    # OPERATION
641
    evm.memory += b"\x00" * extend_memory.expand_by
642
    generic_call(
643
        evm,
644
        message_call_gas.stipend,
645
        U256(0),
646
        evm.message.current_target,
647
        to,
648
        to,
649
        True,
650
        True,
651
        memory_input_start_position,
652
        memory_input_size,
653
        memory_output_start_position,
654
        memory_output_size,
655
    )
656
657
    # PROGRAM COUNTER
658
    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:
662
    """
663
    Stop execution and revert state changes, without consuming all provided gas
664
    and also has the ability to return a reason
665
    Parameters
666
    ----------
667
    evm :
668
        The current EVM frame.
669
    """
670
    # STACK
671
    memory_start_index = pop(evm.stack)
672
    size = pop(evm.stack)
673
674
    # GAS
675
    extend_memory = calculate_gas_extend_memory(
676
        evm.memory, [(memory_start_index, size)]
677
    )
678
679
    charge_gas(evm, extend_memory.cost)
680
681
    # OPERATION
682
    evm.memory += b"\x00" * extend_memory.expand_by
683
    output = memory_read_bytes(evm.memory, memory_start_index, size)
684
    evm.output = bytes(output)
685
    raise Revert
686
687
    # PROGRAM COUNTER
688
    pass