ethereum.prague.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:
70
    """
71
    Core logic used by the `CREATE*` family of opcodes.
72
    """
73
    # This import causes a circular import error
74
    # if it's not moved inside this method
75
    from ...vm.interpreter import (
76
        MAX_INIT_CODE_SIZE,
77
        STACK_DEPTH_LIMIT,
78
        process_create_message,
79
    )
80
81
    call_data = memory_read_bytes(
82
        evm.memory, memory_start_position, memory_size
83
    )
84
    if len(call_data) > MAX_INIT_CODE_SIZE:
85
        raise OutOfGasError
86
87
    create_message_gas = max_message_call_gas(Uint(evm.gas_left))
88
    evm.gas_left -= create_message_gas
89
    if evm.message.is_static:
90
        raise WriteInStaticContext
91
    evm.return_data = b""
92
93
    sender_address = evm.message.current_target
94
    sender = get_account(evm.message.block_env.state, sender_address)
95
96
    if (
97
        sender.balance < endowment
98
        or sender.nonce == Uint(2**64 - 1)
99
        or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT
100
    ):
101
        evm.gas_left += create_message_gas
102
        push(evm.stack, U256(0))
103
        return
104
105
    evm.accessed_addresses.add(contract_address)
106
107
    if account_has_code_or_nonce(
108
        evm.message.block_env.state, contract_address
109
    ) or account_has_storage(evm.message.block_env.state, contract_address):
110
        increment_nonce(
111
            evm.message.block_env.state, evm.message.current_target
112
        )
113
        push(evm.stack, U256(0))
114
        return
115
116
    increment_nonce(evm.message.block_env.state, evm.message.current_target)
117
118
    child_message = Message(
119
        block_env=evm.message.block_env,
120
        tx_env=evm.message.tx_env,
121
        caller=evm.message.current_target,
122
        target=Bytes0(),
123
        gas=create_message_gas,
124
        value=endowment,
125
        data=b"",
126
        code=call_data,
127
        current_target=contract_address,
128
        depth=evm.message.depth + Uint(1),
129
        code_address=None,
130
        should_transfer_value=True,
131
        is_static=False,
132
        accessed_addresses=evm.accessed_addresses.copy(),
133
        accessed_storage_keys=evm.accessed_storage_keys.copy(),
134
        disable_precompiles=False,
135
        parent_evm=evm,
136
    )
137
    child_evm = process_create_message(child_message)
138
139
    if child_evm.error:
140
        incorporate_child_on_error(evm, child_evm)
141
        evm.return_data = child_evm.output
142
        push(evm.stack, U256(0))
143
    else:
144
        incorporate_child_on_success(evm, child_evm)
145
        evm.return_data = b""
146
        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:
150
    """
151
    Creates a new account with associated code.
152
153
    Parameters
154
    ----------
155
    evm :
156
        The current EVM frame.
157
    """
158
    # STACK
159
    endowment = pop(evm.stack)
160
    memory_start_position = pop(evm.stack)
161
    memory_size = pop(evm.stack)
162
163
    # GAS
164
    extend_memory = calculate_gas_extend_memory(
165
        evm.memory, [(memory_start_position, memory_size)]
166
    )
167
    init_code_gas = init_code_cost(Uint(memory_size))
168
169
    charge_gas(evm, GAS_CREATE + extend_memory.cost + init_code_gas)
170
171
    # OPERATION
172
    evm.memory += b"\x00" * extend_memory.expand_by
173
    contract_address = compute_contract_address(
174
        evm.message.current_target,
175
        get_account(
176
            evm.message.block_env.state, evm.message.current_target
177
        ).nonce,
178
    )
179
180
    generic_create(
181
        evm,
182
        endowment,
183
        contract_address,
184
        memory_start_position,
185
        memory_size,
186
    )
187
188
    # PROGRAM COUNTER
189
    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:
193
    """
194
    Creates a new account with associated code.
195
196
    It's similar to CREATE opcode except that the address of new account
197
    depends on the init_code instead of the nonce of sender.
198
199
    Parameters
200
    ----------
201
    evm :
202
        The current EVM frame.
203
    """
204
    # STACK
205
    endowment = pop(evm.stack)
206
    memory_start_position = pop(evm.stack)
207
    memory_size = pop(evm.stack)
208
    salt = pop(evm.stack).to_be_bytes32()
209
210
    # GAS
211
    extend_memory = calculate_gas_extend_memory(
212
        evm.memory, [(memory_start_position, memory_size)]
213
    )
214
    call_data_words = ceil32(Uint(memory_size)) // Uint(32)
215
    init_code_gas = init_code_cost(Uint(memory_size))
216
    charge_gas(
217
        evm,
218
        GAS_CREATE
219
        + GAS_KECCAK256_WORD * call_data_words
220
        + extend_memory.cost
221
        + init_code_gas,
222
    )
223
224
    # OPERATION
225
    evm.memory += b"\x00" * extend_memory.expand_by
226
    contract_address = compute_create2_contract_address(
227
        evm.message.current_target,
228
        salt,
229
        memory_read_bytes(evm.memory, memory_start_position, memory_size),
230
    )
231
232
    generic_create(
233
        evm,
234
        endowment,
235
        contract_address,
236
        memory_start_position,
237
        memory_size,
238
    )
239
240
    # PROGRAM COUNTER
241
    evm.pc += Uint(1)

return_

Halts execution returning output data.

Parameters

evm : The current EVM frame.

def return_(​evm: Evm​) -> None:
245
    """
246
    Halts execution returning output data.
247
248
    Parameters
249
    ----------
250
    evm :
251
        The current EVM frame.
252
    """
253
    # STACK
254
    memory_start_position = pop(evm.stack)
255
    memory_size = pop(evm.stack)
256
257
    # GAS
258
    extend_memory = calculate_gas_extend_memory(
259
        evm.memory, [(memory_start_position, memory_size)]
260
    )
261
262
    charge_gas(evm, GAS_ZERO + extend_memory.cost)
263
264
    # OPERATION
265
    evm.memory += b"\x00" * extend_memory.expand_by
266
    evm.output = memory_read_bytes(
267
        evm.memory, memory_start_position, memory_size
268
    )
269
270
    evm.running = False
271
272
    # PROGRAM COUNTER
273
    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, ​​code: Bytes, ​​disable_precompiles: bool​) -> None:
292
    """
293
    Perform the core logic of the `CALL*` family of opcodes.
294
    """
295
    from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message
296
297
    evm.return_data = b""
298
299
    if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT:
300
        evm.gas_left += gas
301
        push(evm.stack, U256(0))
302
        return
303
304
    call_data = memory_read_bytes(
305
        evm.memory, memory_input_start_position, memory_input_size
306
    )
307
308
    child_message = Message(
309
        block_env=evm.message.block_env,
310
        tx_env=evm.message.tx_env,
311
        caller=caller,
312
        target=to,
313
        gas=gas,
314
        value=value,
315
        data=call_data,
316
        code=code,
317
        current_target=to,
318
        depth=evm.message.depth + Uint(1),
319
        code_address=code_address,
320
        should_transfer_value=should_transfer_value,
321
        is_static=True if is_staticcall else evm.message.is_static,
322
        accessed_addresses=evm.accessed_addresses.copy(),
323
        accessed_storage_keys=evm.accessed_storage_keys.copy(),
324
        disable_precompiles=disable_precompiles,
325
        parent_evm=evm,
326
    )
327
    child_evm = process_message(child_message)
328
329
    if child_evm.error:
330
        incorporate_child_on_error(evm, child_evm)
331
        evm.return_data = child_evm.output
332
        push(evm.stack, U256(0))
333
    else:
334
        incorporate_child_on_success(evm, child_evm)
335
        evm.return_data = child_evm.output
336
        push(evm.stack, U256(1))
337
338
    actual_output_size = min(memory_output_size, U256(len(child_evm.output)))
339
    memory_write(
340
        evm.memory,
341
        memory_output_start_position,
342
        child_evm.output[:actual_output_size],
343
    )

call

Message-call into an account.

Parameters

evm : The current EVM frame.

def call(​evm: Evm​) -> None:
347
    """
348
    Message-call into an account.
349
350
    Parameters
351
    ----------
352
    evm :
353
        The current EVM frame.
354
    """
355
    # STACK
356
    gas = Uint(pop(evm.stack))
357
    to = to_address(pop(evm.stack))
358
    value = pop(evm.stack)
359
    memory_input_start_position = pop(evm.stack)
360
    memory_input_size = pop(evm.stack)
361
    memory_output_start_position = pop(evm.stack)
362
    memory_output_size = pop(evm.stack)
363
364
    # GAS
365
    extend_memory = calculate_gas_extend_memory(
366
        evm.memory,
367
        [
368
            (memory_input_start_position, memory_input_size),
369
            (memory_output_start_position, memory_output_size),
370
        ],
371
    )
372
373
    if to in evm.accessed_addresses:
374
        access_gas_cost = GAS_WARM_ACCESS
375
    else:
376
        evm.accessed_addresses.add(to)
377
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
378
379
    code_address = to
380
    (
381
        disable_precompiles,
382
        code_address,
383
        code,
384
        delegated_access_gas_cost,
385
    ) = access_delegation(evm, code_address)
386
    access_gas_cost += delegated_access_gas_cost
387
388
    create_gas_cost = (
389
        Uint(0)
390
        if is_account_alive(evm.message.block_env.state, to) or value == 0
391
        else GAS_NEW_ACCOUNT
392
    )
393
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
394
    message_call_gas = calculate_message_call_gas(
395
        value,
396
        gas,
397
        Uint(evm.gas_left),
398
        extend_memory.cost,
399
        access_gas_cost + create_gas_cost + transfer_gas_cost,
400
    )
401
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
402
    if evm.message.is_static and value != U256(0):
403
        raise WriteInStaticContext
404
    evm.memory += b"\x00" * extend_memory.expand_by
405
    sender_balance = get_account(
406
        evm.message.block_env.state, evm.message.current_target
407
    ).balance
408
    if sender_balance < value:
409
        push(evm.stack, U256(0))
410
        evm.return_data = b""
411
        evm.gas_left += message_call_gas.sub_call
412
    else:
413
        generic_call(
414
            evm,
415
            message_call_gas.sub_call,
416
            value,
417
            evm.message.current_target,
418
            to,
419
            code_address,
420
            True,
421
            False,
422
            memory_input_start_position,
423
            memory_input_size,
424
            memory_output_start_position,
425
            memory_output_size,
426
            code,
427
            disable_precompiles,
428
        )
429
430
    # PROGRAM COUNTER
431
    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:
435
    """
436
    Message-call into this account with alternative account’s code.
437
438
    Parameters
439
    ----------
440
    evm :
441
        The current EVM frame.
442
    """
443
    # STACK
444
    gas = Uint(pop(evm.stack))
445
    code_address = to_address(pop(evm.stack))
446
    value = pop(evm.stack)
447
    memory_input_start_position = pop(evm.stack)
448
    memory_input_size = pop(evm.stack)
449
    memory_output_start_position = pop(evm.stack)
450
    memory_output_size = pop(evm.stack)
451
452
    # GAS
453
    to = evm.message.current_target
454
455
    extend_memory = calculate_gas_extend_memory(
456
        evm.memory,
457
        [
458
            (memory_input_start_position, memory_input_size),
459
            (memory_output_start_position, memory_output_size),
460
        ],
461
    )
462
463
    if code_address in evm.accessed_addresses:
464
        access_gas_cost = GAS_WARM_ACCESS
465
    else:
466
        evm.accessed_addresses.add(code_address)
467
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
468
469
    (
470
        disable_precompiles,
471
        code_address,
472
        code,
473
        delegated_access_gas_cost,
474
    ) = access_delegation(evm, code_address)
475
    access_gas_cost += delegated_access_gas_cost
476
477
    transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE
478
    message_call_gas = calculate_message_call_gas(
479
        value,
480
        gas,
481
        Uint(evm.gas_left),
482
        extend_memory.cost,
483
        access_gas_cost + transfer_gas_cost,
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
    sender_balance = get_account(
490
        evm.message.block_env.state, evm.message.current_target
491
    ).balance
492
    if sender_balance < value:
493
        push(evm.stack, U256(0))
494
        evm.return_data = b""
495
        evm.gas_left += message_call_gas.sub_call
496
    else:
497
        generic_call(
498
            evm,
499
            message_call_gas.sub_call,
500
            value,
501
            evm.message.current_target,
502
            to,
503
            code_address,
504
            True,
505
            False,
506
            memory_input_start_position,
507
            memory_input_size,
508
            memory_output_start_position,
509
            memory_output_size,
510
            code,
511
            disable_precompiles,
512
        )
513
514
    # PROGRAM COUNTER
515
    evm.pc += Uint(1)

selfdestruct

Halt execution and register account for later deletion.

Parameters

evm : The current EVM frame.

def selfdestruct(​evm: Evm​) -> None:
519
    """
520
    Halt execution and register account for later deletion.
521
522
    Parameters
523
    ----------
524
    evm :
525
        The current EVM frame.
526
    """
527
    # STACK
528
    beneficiary = to_address(pop(evm.stack))
529
530
    # GAS
531
    gas_cost = GAS_SELF_DESTRUCT
532
    if beneficiary not in evm.accessed_addresses:
533
        evm.accessed_addresses.add(beneficiary)
534
        gas_cost += GAS_COLD_ACCOUNT_ACCESS
535
536
    if (
537
        not is_account_alive(evm.message.block_env.state, beneficiary)
538
        and get_account(
539
            evm.message.block_env.state, evm.message.current_target
540
        ).balance
541
        != 0
542
    ):
543
        gas_cost += GAS_SELF_DESTRUCT_NEW_ACCOUNT
544
545
    charge_gas(evm, gas_cost)
546
    if evm.message.is_static:
547
        raise WriteInStaticContext
548
549
    originator = evm.message.current_target
550
    originator_balance = get_account(
551
        evm.message.block_env.state, originator
552
    ).balance
553
554
    move_ether(
555
        evm.message.block_env.state,
556
        originator,
557
        beneficiary,
558
        originator_balance,
559
    )
560
561
    # register account for deletion only if it was created
562
    # in the same transaction
563
    if originator in evm.message.block_env.state.created_accounts:
564
        # If beneficiary is the same as originator, then
565
        # the ether is burnt.
566
        set_account_balance(evm.message.block_env.state, originator, U256(0))
567
        evm.accounts_to_delete.add(originator)
568
569
    # HALT the execution
570
    evm.running = False
571
572
    # PROGRAM COUNTER
573
    pass

delegatecall

Message-call into an account.

Parameters

evm : The current EVM frame.

def delegatecall(​evm: Evm​) -> None:
577
    """
578
    Message-call into an account.
579
580
    Parameters
581
    ----------
582
    evm :
583
        The current EVM frame.
584
    """
585
    # STACK
586
    gas = Uint(pop(evm.stack))
587
    code_address = to_address(pop(evm.stack))
588
    memory_input_start_position = pop(evm.stack)
589
    memory_input_size = pop(evm.stack)
590
    memory_output_start_position = pop(evm.stack)
591
    memory_output_size = pop(evm.stack)
592
593
    # GAS
594
    extend_memory = calculate_gas_extend_memory(
595
        evm.memory,
596
        [
597
            (memory_input_start_position, memory_input_size),
598
            (memory_output_start_position, memory_output_size),
599
        ],
600
    )
601
602
    if code_address in evm.accessed_addresses:
603
        access_gas_cost = GAS_WARM_ACCESS
604
    else:
605
        evm.accessed_addresses.add(code_address)
606
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
607
608
    (
609
        disable_precompiles,
610
        code_address,
611
        code,
612
        delegated_access_gas_cost,
613
    ) = access_delegation(evm, code_address)
614
    access_gas_cost += delegated_access_gas_cost
615
616
    message_call_gas = calculate_message_call_gas(
617
        U256(0), gas, Uint(evm.gas_left), extend_memory.cost, access_gas_cost
618
    )
619
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
620
621
    # OPERATION
622
    evm.memory += b"\x00" * extend_memory.expand_by
623
    generic_call(
624
        evm,
625
        message_call_gas.sub_call,
626
        evm.message.value,
627
        evm.message.caller,
628
        evm.message.current_target,
629
        code_address,
630
        False,
631
        False,
632
        memory_input_start_position,
633
        memory_input_size,
634
        memory_output_start_position,
635
        memory_output_size,
636
        code,
637
        disable_precompiles,
638
    )
639
640
    # PROGRAM COUNTER
641
    evm.pc += Uint(1)

staticcall

Message-call into an account.

Parameters

evm : The current EVM frame.

def staticcall(​evm: Evm​) -> None:
645
    """
646
    Message-call into an account.
647
648
    Parameters
649
    ----------
650
    evm :
651
        The current EVM frame.
652
    """
653
    # STACK
654
    gas = Uint(pop(evm.stack))
655
    to = to_address(pop(evm.stack))
656
    memory_input_start_position = pop(evm.stack)
657
    memory_input_size = pop(evm.stack)
658
    memory_output_start_position = pop(evm.stack)
659
    memory_output_size = pop(evm.stack)
660
661
    # GAS
662
    extend_memory = calculate_gas_extend_memory(
663
        evm.memory,
664
        [
665
            (memory_input_start_position, memory_input_size),
666
            (memory_output_start_position, memory_output_size),
667
        ],
668
    )
669
670
    if to in evm.accessed_addresses:
671
        access_gas_cost = GAS_WARM_ACCESS
672
    else:
673
        evm.accessed_addresses.add(to)
674
        access_gas_cost = GAS_COLD_ACCOUNT_ACCESS
675
676
    code_address = to
677
    (
678
        disable_precompiles,
679
        code_address,
680
        code,
681
        delegated_access_gas_cost,
682
    ) = access_delegation(evm, code_address)
683
    access_gas_cost += delegated_access_gas_cost
684
685
    message_call_gas = calculate_message_call_gas(
686
        U256(0),
687
        gas,
688
        Uint(evm.gas_left),
689
        extend_memory.cost,
690
        access_gas_cost,
691
    )
692
    charge_gas(evm, message_call_gas.cost + extend_memory.cost)
693
694
    # OPERATION
695
    evm.memory += b"\x00" * extend_memory.expand_by
696
    generic_call(
697
        evm,
698
        message_call_gas.sub_call,
699
        U256(0),
700
        evm.message.current_target,
701
        to,
702
        code_address,
703
        True,
704
        True,
705
        memory_input_start_position,
706
        memory_input_size,
707
        memory_output_start_position,
708
        memory_output_size,
709
        code,
710
        disable_precompiles,
711
    )
712
713
    # PROGRAM COUNTER
714
    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:
718
    """
719
    Stop execution and revert state changes, without consuming all provided gas
720
    and also has the ability to return a reason
721
    Parameters
722
    ----------
723
    evm :
724
        The current EVM frame.
725
    """
726
    # STACK
727
    memory_start_index = pop(evm.stack)
728
    size = pop(evm.stack)
729
730
    # GAS
731
    extend_memory = calculate_gas_extend_memory(
732
        evm.memory, [(memory_start_index, size)]
733
    )
734
735
    charge_gas(evm, extend_memory.cost)
736
737
    # OPERATION
738
    evm.memory += b"\x00" * extend_memory.expand_by
739
    output = memory_read_bytes(evm.memory, memory_start_index, size)
740
    evm.output = Bytes(output)
741
    raise Revert