ethereum.forks.osaka.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 ( |
| 75 | MAX_INIT_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) > MAX_INIT_CODE_SIZE: |
| 84 | raise OutOfGasError |
| 85 | |
| 86 | create_message_gas = max_message_call_gas(Uint(evm.gas_left)) |
| 87 | evm.gas_left -= create_message_gas |
| 88 | if evm.message.is_static: |
| 89 | raise WriteInStaticContext |
| 90 | evm.return_data = b"" |
| 91 | |
| 92 | sender_address = evm.message.current_target |
| 93 | sender = get_account(evm.message.block_env.state, sender_address) |
| 94 | |
| 95 | if ( |
| 96 | sender.balance < endowment |
| 97 | or sender.nonce == Uint(2**64 - 1) |
| 98 | or evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT |
| 99 | ): |
| 100 | evm.gas_left += create_message_gas |
| 101 | push(evm.stack, U256(0)) |
| 102 | return |
| 103 | |
| 104 | evm.accessed_addresses.add(contract_address) |
| 105 | |
| 106 | if account_has_code_or_nonce( |
| 107 | evm.message.block_env.state, contract_address |
| 108 | ) or account_has_storage(evm.message.block_env.state, contract_address): |
| 109 | increment_nonce( |
| 110 | evm.message.block_env.state, evm.message.current_target |
| 111 | ) |
| 112 | push(evm.stack, U256(0)) |
| 113 | return |
| 114 | |
| 115 | increment_nonce(evm.message.block_env.state, evm.message.current_target) |
| 116 | |
| 117 | child_message = Message( |
| 118 | block_env=evm.message.block_env, |
| 119 | tx_env=evm.message.tx_env, |
| 120 | caller=evm.message.current_target, |
| 121 | target=Bytes0(), |
| 122 | gas=create_message_gas, |
| 123 | value=endowment, |
| 124 | data=b"", |
| 125 | code=call_data, |
| 126 | current_target=contract_address, |
| 127 | depth=evm.message.depth + Uint(1), |
| 128 | code_address=None, |
| 129 | should_transfer_value=True, |
| 130 | is_static=False, |
| 131 | accessed_addresses=evm.accessed_addresses.copy(), |
| 132 | accessed_storage_keys=evm.accessed_storage_keys.copy(), |
| 133 | disable_precompiles=False, |
| 134 | parent_evm=evm, |
| 135 | ) |
| 136 | child_evm = process_create_message(child_message) |
| 137 | |
| 138 | if child_evm.error: |
| 139 | incorporate_child_on_error(evm, child_evm) |
| 140 | evm.return_data = child_evm.output |
| 141 | push(evm.stack, U256(0)) |
| 142 | else: |
| 143 | incorporate_child_on_success(evm, child_evm) |
| 144 | evm.return_data = b"" |
| 145 | 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:
| 149 | """ |
|---|---|
| 150 | Creates a new account with associated code. |
| 151 | |
| 152 | Parameters |
| 153 | ---------- |
| 154 | evm : |
| 155 | The current EVM frame. |
| 156 | |
| 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 | """ |
| 205 | # STACK |
| 206 | endowment = pop(evm.stack) |
| 207 | memory_start_position = pop(evm.stack) |
| 208 | memory_size = pop(evm.stack) |
| 209 | salt = pop(evm.stack).to_be_bytes32() |
| 210 | |
| 211 | # GAS |
| 212 | extend_memory = calculate_gas_extend_memory( |
| 213 | evm.memory, [(memory_start_position, memory_size)] |
| 214 | ) |
| 215 | call_data_words = ceil32(Uint(memory_size)) // Uint(32) |
| 216 | init_code_gas = init_code_cost(Uint(memory_size)) |
| 217 | charge_gas( |
| 218 | evm, |
| 219 | GAS_CREATE |
| 220 | + GAS_KECCAK256_WORD * call_data_words |
| 221 | + extend_memory.cost |
| 222 | + init_code_gas, |
| 223 | ) |
| 224 | |
| 225 | # OPERATION |
| 226 | evm.memory += b"\x00" * extend_memory.expand_by |
| 227 | contract_address = compute_create2_contract_address( |
| 228 | evm.message.current_target, |
| 229 | salt, |
| 230 | memory_read_bytes(evm.memory, memory_start_position, memory_size), |
| 231 | ) |
| 232 | |
| 233 | generic_create( |
| 234 | evm, |
| 235 | endowment, |
| 236 | contract_address, |
| 237 | memory_start_position, |
| 238 | memory_size, |
| 239 | ) |
| 240 | |
| 241 | # PROGRAM COUNTER |
| 242 | evm.pc += Uint(1) |
return_
Halts execution returning output data.
Parameters
evm : The current EVM frame.
def return_(evm: Evm) -> None:
| 246 | """ |
|---|---|
| 247 | Halts execution returning output data. |
| 248 | |
| 249 | Parameters |
| 250 | ---------- |
| 251 | evm : |
| 252 | The current EVM frame. |
| 253 | |
| 254 | """ |
| 255 | # STACK |
| 256 | memory_start_position = pop(evm.stack) |
| 257 | memory_size = pop(evm.stack) |
| 258 | |
| 259 | # GAS |
| 260 | extend_memory = calculate_gas_extend_memory( |
| 261 | evm.memory, [(memory_start_position, memory_size)] |
| 262 | ) |
| 263 | |
| 264 | charge_gas(evm, GAS_ZERO + extend_memory.cost) |
| 265 | |
| 266 | # OPERATION |
| 267 | evm.memory += b"\x00" * extend_memory.expand_by |
| 268 | evm.output = memory_read_bytes( |
| 269 | evm.memory, memory_start_position, memory_size |
| 270 | ) |
| 271 | |
| 272 | evm.running = False |
| 273 | |
| 274 | # PROGRAM COUNTER |
| 275 | 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:
| 294 | """ |
|---|---|
| 295 | Perform the core logic of the `CALL*` family of opcodes. |
| 296 | """ |
| 297 | from ...vm.interpreter import STACK_DEPTH_LIMIT, process_message |
| 298 | |
| 299 | evm.return_data = b"" |
| 300 | |
| 301 | if evm.message.depth + Uint(1) > STACK_DEPTH_LIMIT: |
| 302 | evm.gas_left += gas |
| 303 | push(evm.stack, U256(0)) |
| 304 | return |
| 305 | |
| 306 | call_data = memory_read_bytes( |
| 307 | evm.memory, memory_input_start_position, memory_input_size |
| 308 | ) |
| 309 | |
| 310 | child_message = Message( |
| 311 | block_env=evm.message.block_env, |
| 312 | tx_env=evm.message.tx_env, |
| 313 | caller=caller, |
| 314 | target=to, |
| 315 | gas=gas, |
| 316 | value=value, |
| 317 | data=call_data, |
| 318 | code=code, |
| 319 | current_target=to, |
| 320 | depth=evm.message.depth + Uint(1), |
| 321 | code_address=code_address, |
| 322 | should_transfer_value=should_transfer_value, |
| 323 | is_static=True if is_staticcall else evm.message.is_static, |
| 324 | accessed_addresses=evm.accessed_addresses.copy(), |
| 325 | accessed_storage_keys=evm.accessed_storage_keys.copy(), |
| 326 | disable_precompiles=disable_precompiles, |
| 327 | parent_evm=evm, |
| 328 | ) |
| 329 | child_evm = process_message(child_message) |
| 330 | |
| 331 | if child_evm.error: |
| 332 | incorporate_child_on_error(evm, child_evm) |
| 333 | evm.return_data = child_evm.output |
| 334 | push(evm.stack, U256(0)) |
| 335 | else: |
| 336 | incorporate_child_on_success(evm, child_evm) |
| 337 | evm.return_data = child_evm.output |
| 338 | push(evm.stack, U256(1)) |
| 339 | |
| 340 | actual_output_size = min(memory_output_size, U256(len(child_evm.output))) |
| 341 | memory_write( |
| 342 | evm.memory, |
| 343 | memory_output_start_position, |
| 344 | child_evm.output[:actual_output_size], |
| 345 | ) |
call
Message-call into an account.
Parameters
evm : The current EVM frame.
def call(evm: Evm) -> None:
| 349 | """ |
|---|---|
| 350 | Message-call into an account. |
| 351 | |
| 352 | Parameters |
| 353 | ---------- |
| 354 | evm : |
| 355 | The current EVM frame. |
| 356 | |
| 357 | """ |
| 358 | # STACK |
| 359 | gas = Uint(pop(evm.stack)) |
| 360 | to = to_address_masked(pop(evm.stack)) |
| 361 | value = pop(evm.stack) |
| 362 | memory_input_start_position = pop(evm.stack) |
| 363 | memory_input_size = pop(evm.stack) |
| 364 | memory_output_start_position = pop(evm.stack) |
| 365 | memory_output_size = pop(evm.stack) |
| 366 | |
| 367 | # GAS |
| 368 | extend_memory = calculate_gas_extend_memory( |
| 369 | evm.memory, |
| 370 | [ |
| 371 | (memory_input_start_position, memory_input_size), |
| 372 | (memory_output_start_position, memory_output_size), |
| 373 | ], |
| 374 | ) |
| 375 | |
| 376 | if to in evm.accessed_addresses: |
| 377 | access_gas_cost = GAS_WARM_ACCESS |
| 378 | else: |
| 379 | evm.accessed_addresses.add(to) |
| 380 | access_gas_cost = GAS_COLD_ACCOUNT_ACCESS |
| 381 | |
| 382 | code_address = to |
| 383 | ( |
| 384 | disable_precompiles, |
| 385 | code_address, |
| 386 | code, |
| 387 | delegated_access_gas_cost, |
| 388 | ) = access_delegation(evm, code_address) |
| 389 | access_gas_cost += delegated_access_gas_cost |
| 390 | |
| 391 | create_gas_cost = GAS_NEW_ACCOUNT |
| 392 | if value == 0 or is_account_alive(evm.message.block_env.state, to): |
| 393 | create_gas_cost = Uint(0) |
| 394 | transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE |
| 395 | message_call_gas = calculate_message_call_gas( |
| 396 | value, |
| 397 | gas, |
| 398 | Uint(evm.gas_left), |
| 399 | extend_memory.cost, |
| 400 | access_gas_cost + create_gas_cost + transfer_gas_cost, |
| 401 | ) |
| 402 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
| 403 | if evm.message.is_static and value != U256(0): |
| 404 | raise WriteInStaticContext |
| 405 | evm.memory += b"\x00" * extend_memory.expand_by |
| 406 | sender_balance = get_account( |
| 407 | evm.message.block_env.state, evm.message.current_target |
| 408 | ).balance |
| 409 | if sender_balance < value: |
| 410 | push(evm.stack, U256(0)) |
| 411 | evm.return_data = b"" |
| 412 | evm.gas_left += message_call_gas.sub_call |
| 413 | else: |
| 414 | generic_call( |
| 415 | evm, |
| 416 | message_call_gas.sub_call, |
| 417 | value, |
| 418 | evm.message.current_target, |
| 419 | to, |
| 420 | code_address, |
| 421 | True, |
| 422 | False, |
| 423 | memory_input_start_position, |
| 424 | memory_input_size, |
| 425 | memory_output_start_position, |
| 426 | memory_output_size, |
| 427 | code, |
| 428 | disable_precompiles, |
| 429 | ) |
| 430 | |
| 431 | # PROGRAM COUNTER |
| 432 | 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:
| 436 | """ |
|---|---|
| 437 | Message-call into this account with alternative account’s code. |
| 438 | |
| 439 | Parameters |
| 440 | ---------- |
| 441 | evm : |
| 442 | The current EVM frame. |
| 443 | |
| 444 | """ |
| 445 | # STACK |
| 446 | gas = Uint(pop(evm.stack)) |
| 447 | code_address = to_address_masked(pop(evm.stack)) |
| 448 | value = pop(evm.stack) |
| 449 | memory_input_start_position = pop(evm.stack) |
| 450 | memory_input_size = pop(evm.stack) |
| 451 | memory_output_start_position = pop(evm.stack) |
| 452 | memory_output_size = pop(evm.stack) |
| 453 | |
| 454 | # GAS |
| 455 | to = evm.message.current_target |
| 456 | |
| 457 | extend_memory = calculate_gas_extend_memory( |
| 458 | evm.memory, |
| 459 | [ |
| 460 | (memory_input_start_position, memory_input_size), |
| 461 | (memory_output_start_position, memory_output_size), |
| 462 | ], |
| 463 | ) |
| 464 | |
| 465 | if code_address in evm.accessed_addresses: |
| 466 | access_gas_cost = GAS_WARM_ACCESS |
| 467 | else: |
| 468 | evm.accessed_addresses.add(code_address) |
| 469 | access_gas_cost = GAS_COLD_ACCOUNT_ACCESS |
| 470 | |
| 471 | ( |
| 472 | disable_precompiles, |
| 473 | code_address, |
| 474 | code, |
| 475 | delegated_access_gas_cost, |
| 476 | ) = access_delegation(evm, code_address) |
| 477 | access_gas_cost += delegated_access_gas_cost |
| 478 | |
| 479 | transfer_gas_cost = Uint(0) if value == 0 else GAS_CALL_VALUE |
| 480 | message_call_gas = calculate_message_call_gas( |
| 481 | value, |
| 482 | gas, |
| 483 | Uint(evm.gas_left), |
| 484 | extend_memory.cost, |
| 485 | access_gas_cost + transfer_gas_cost, |
| 486 | ) |
| 487 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
| 488 | |
| 489 | # OPERATION |
| 490 | evm.memory += b"\x00" * extend_memory.expand_by |
| 491 | sender_balance = get_account( |
| 492 | evm.message.block_env.state, evm.message.current_target |
| 493 | ).balance |
| 494 | if sender_balance < value: |
| 495 | push(evm.stack, U256(0)) |
| 496 | evm.return_data = b"" |
| 497 | evm.gas_left += message_call_gas.sub_call |
| 498 | else: |
| 499 | generic_call( |
| 500 | evm, |
| 501 | message_call_gas.sub_call, |
| 502 | value, |
| 503 | evm.message.current_target, |
| 504 | to, |
| 505 | code_address, |
| 506 | True, |
| 507 | False, |
| 508 | memory_input_start_position, |
| 509 | memory_input_size, |
| 510 | memory_output_start_position, |
| 511 | memory_output_size, |
| 512 | code, |
| 513 | disable_precompiles, |
| 514 | ) |
| 515 | |
| 516 | # PROGRAM COUNTER |
| 517 | evm.pc += Uint(1) |
selfdestruct
Halt execution and register account for later deletion.
Parameters
evm : The current EVM frame.
def selfdestruct(evm: Evm) -> None:
| 521 | """ |
|---|---|
| 522 | Halt execution and register account for later deletion. |
| 523 | |
| 524 | Parameters |
| 525 | ---------- |
| 526 | evm : |
| 527 | The current EVM frame. |
| 528 | |
| 529 | """ |
| 530 | # STACK |
| 531 | beneficiary = to_address_masked(pop(evm.stack)) |
| 532 | |
| 533 | # GAS |
| 534 | gas_cost = GAS_SELF_DESTRUCT |
| 535 | if beneficiary not in evm.accessed_addresses: |
| 536 | evm.accessed_addresses.add(beneficiary) |
| 537 | gas_cost += GAS_COLD_ACCOUNT_ACCESS |
| 538 | |
| 539 | if ( |
| 540 | not is_account_alive(evm.message.block_env.state, beneficiary) |
| 541 | and get_account( |
| 542 | evm.message.block_env.state, evm.message.current_target |
| 543 | ).balance |
| 544 | != 0 |
| 545 | ): |
| 546 | gas_cost += GAS_SELF_DESTRUCT_NEW_ACCOUNT |
| 547 | |
| 548 | charge_gas(evm, gas_cost) |
| 549 | if evm.message.is_static: |
| 550 | raise WriteInStaticContext |
| 551 | |
| 552 | originator = evm.message.current_target |
| 553 | originator_balance = get_account( |
| 554 | evm.message.block_env.state, originator |
| 555 | ).balance |
| 556 | |
| 557 | move_ether( |
| 558 | evm.message.block_env.state, |
| 559 | originator, |
| 560 | beneficiary, |
| 561 | originator_balance, |
| 562 | ) |
| 563 | |
| 564 | # register account for deletion only if it was created |
| 565 | # in the same transaction |
| 566 | if originator in evm.message.block_env.state.created_accounts: |
| 567 | # If beneficiary is the same as originator, then |
| 568 | # the ether is burnt. |
| 569 | set_account_balance(evm.message.block_env.state, originator, U256(0)) |
| 570 | evm.accounts_to_delete.add(originator) |
| 571 | |
| 572 | # HALT the execution |
| 573 | evm.running = False |
| 574 | |
| 575 | # PROGRAM COUNTER |
| 576 | pass |
delegatecall
Message-call into an account.
Parameters
evm : The current EVM frame.
def delegatecall(evm: Evm) -> None:
| 580 | """ |
|---|---|
| 581 | Message-call into an account. |
| 582 | |
| 583 | Parameters |
| 584 | ---------- |
| 585 | evm : |
| 586 | The current EVM frame. |
| 587 | |
| 588 | """ |
| 589 | # STACK |
| 590 | gas = Uint(pop(evm.stack)) |
| 591 | code_address = to_address_masked(pop(evm.stack)) |
| 592 | memory_input_start_position = pop(evm.stack) |
| 593 | memory_input_size = pop(evm.stack) |
| 594 | memory_output_start_position = pop(evm.stack) |
| 595 | memory_output_size = pop(evm.stack) |
| 596 | |
| 597 | # GAS |
| 598 | extend_memory = calculate_gas_extend_memory( |
| 599 | evm.memory, |
| 600 | [ |
| 601 | (memory_input_start_position, memory_input_size), |
| 602 | (memory_output_start_position, memory_output_size), |
| 603 | ], |
| 604 | ) |
| 605 | |
| 606 | if code_address in evm.accessed_addresses: |
| 607 | access_gas_cost = GAS_WARM_ACCESS |
| 608 | else: |
| 609 | evm.accessed_addresses.add(code_address) |
| 610 | access_gas_cost = GAS_COLD_ACCOUNT_ACCESS |
| 611 | |
| 612 | ( |
| 613 | disable_precompiles, |
| 614 | code_address, |
| 615 | code, |
| 616 | delegated_access_gas_cost, |
| 617 | ) = access_delegation(evm, code_address) |
| 618 | access_gas_cost += delegated_access_gas_cost |
| 619 | |
| 620 | message_call_gas = calculate_message_call_gas( |
| 621 | U256(0), gas, Uint(evm.gas_left), extend_memory.cost, access_gas_cost |
| 622 | ) |
| 623 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
| 624 | |
| 625 | # OPERATION |
| 626 | evm.memory += b"\x00" * extend_memory.expand_by |
| 627 | generic_call( |
| 628 | evm, |
| 629 | message_call_gas.sub_call, |
| 630 | evm.message.value, |
| 631 | evm.message.caller, |
| 632 | evm.message.current_target, |
| 633 | code_address, |
| 634 | False, |
| 635 | False, |
| 636 | memory_input_start_position, |
| 637 | memory_input_size, |
| 638 | memory_output_start_position, |
| 639 | memory_output_size, |
| 640 | code, |
| 641 | disable_precompiles, |
| 642 | ) |
| 643 | |
| 644 | # PROGRAM COUNTER |
| 645 | evm.pc += Uint(1) |
staticcall
Message-call into an account.
Parameters
evm : The current EVM frame.
def staticcall(evm: Evm) -> None:
| 649 | """ |
|---|---|
| 650 | Message-call into an account. |
| 651 | |
| 652 | Parameters |
| 653 | ---------- |
| 654 | evm : |
| 655 | The current EVM frame. |
| 656 | |
| 657 | """ |
| 658 | # STACK |
| 659 | gas = Uint(pop(evm.stack)) |
| 660 | to = to_address_masked(pop(evm.stack)) |
| 661 | memory_input_start_position = pop(evm.stack) |
| 662 | memory_input_size = pop(evm.stack) |
| 663 | memory_output_start_position = pop(evm.stack) |
| 664 | memory_output_size = pop(evm.stack) |
| 665 | |
| 666 | # GAS |
| 667 | extend_memory = calculate_gas_extend_memory( |
| 668 | evm.memory, |
| 669 | [ |
| 670 | (memory_input_start_position, memory_input_size), |
| 671 | (memory_output_start_position, memory_output_size), |
| 672 | ], |
| 673 | ) |
| 674 | |
| 675 | if to in evm.accessed_addresses: |
| 676 | access_gas_cost = GAS_WARM_ACCESS |
| 677 | else: |
| 678 | evm.accessed_addresses.add(to) |
| 679 | access_gas_cost = GAS_COLD_ACCOUNT_ACCESS |
| 680 | |
| 681 | code_address = to |
| 682 | ( |
| 683 | disable_precompiles, |
| 684 | code_address, |
| 685 | code, |
| 686 | delegated_access_gas_cost, |
| 687 | ) = access_delegation(evm, code_address) |
| 688 | access_gas_cost += delegated_access_gas_cost |
| 689 | |
| 690 | message_call_gas = calculate_message_call_gas( |
| 691 | U256(0), |
| 692 | gas, |
| 693 | Uint(evm.gas_left), |
| 694 | extend_memory.cost, |
| 695 | access_gas_cost, |
| 696 | ) |
| 697 | charge_gas(evm, message_call_gas.cost + extend_memory.cost) |
| 698 | |
| 699 | # OPERATION |
| 700 | evm.memory += b"\x00" * extend_memory.expand_by |
| 701 | generic_call( |
| 702 | evm, |
| 703 | message_call_gas.sub_call, |
| 704 | U256(0), |
| 705 | evm.message.current_target, |
| 706 | to, |
| 707 | code_address, |
| 708 | True, |
| 709 | True, |
| 710 | memory_input_start_position, |
| 711 | memory_input_size, |
| 712 | memory_output_start_position, |
| 713 | memory_output_size, |
| 714 | code, |
| 715 | disable_precompiles, |
| 716 | ) |
| 717 | |
| 718 | # PROGRAM COUNTER |
| 719 | 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:
| 723 | """ |
|---|---|
| 724 | Stop execution and revert state changes, without consuming all provided gas |
| 725 | and also has the ability to return a reason. |
| 726 | |
| 727 | Parameters |
| 728 | ---------- |
| 729 | evm : |
| 730 | The current EVM frame. |
| 731 | |
| 732 | """ |
| 733 | # STACK |
| 734 | memory_start_index = pop(evm.stack) |
| 735 | size = pop(evm.stack) |
| 736 | |
| 737 | # GAS |
| 738 | extend_memory = calculate_gas_extend_memory( |
| 739 | evm.memory, [(memory_start_index, size)] |
| 740 | ) |
| 741 | |
| 742 | charge_gas(evm, extend_memory.cost) |
| 743 | |
| 744 | # OPERATION |
| 745 | evm.memory += b"\x00" * extend_memory.expand_by |
| 746 | output = memory_read_bytes(evm.memory, memory_start_index, size) |
| 747 | evm.output = Bytes(output) |
| 748 | raise Revert |