nimbus-eth1/nimbus/vm/interpreter/opcodes_impl.nim

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# Nimbus
# Copyright (c) 2018-2019 Status Research & Development GmbH
# Licensed under either of
# * Apache License, version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
# * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
# at your option. This file may not be copied, modified, or distributed except according to those terms.
import
strformat, times, sets, sequtils, options,
chronicles, stint, nimcrypto, stew/ranges/[ptr_arith], eth/common,
./utils/[macros_procs_opcodes, utils_numeric],
./gas_meter, ./gas_costs, ./opcode_values, ./vm_forks,
../memory, ../stack, ../code_stream, ../computation,
../../vm_state, ../../errors, ../../constants, ../../vm_types,
../../db/[db_chain, state_db]
when defined(evmc_enabled):
import ../evmc_api, ../evmc_helpers, evmc/evmc
logScope:
topics = "opcode impl"
# ##################################
# Syntactic sugar
template push(x: typed) {.dirty.} =
## Push an expression on the computation stack
c.stack.push x
# ##################################
# 0s: Stop and Arithmetic Operations
op add, inline = true, lhs, rhs:
## 0x01, Addition
push: lhs + rhs
op mul, inline = true, lhs, rhs:
## 0x02, Multiplication
push: lhs * rhs
op sub, inline = true, lhs, rhs:
## 0x03, Substraction
push: lhs - rhs
op divide, inline = true, lhs, rhs:
## 0x04, Division
push:
if rhs == 0: zero(Uint256) # EVM special casing of div by 0
else: lhs div rhs
op sdiv, inline = true, lhs, rhs:
## 0x05, Signed division
var r: UInt256
if rhs != 0:
var a = lhs
var b = rhs
var signA, signB: bool
extractSign(a, signA)
extractSign(b, signB)
r = a div b
setSign(r, signA xor signB)
push(r)
op modulo, inline = true, lhs, rhs:
## 0x06, Modulo
push:
if rhs == 0: zero(Uint256)
else: lhs mod rhs
op smod, inline = true, lhs, rhs:
## 0x07, Signed modulo
var r: UInt256
if rhs != 0:
var sign: bool
var v = lhs
var m = rhs
extractSign(m, sign)
extractSign(v, sign)
r = v mod m
setSign(r, sign)
push(r)
op addmod, inline = true, lhs, rhs, modulus:
## 0x08, Modulo addition
## Intermediate computations do not roll over at 2^256
push:
if modulus == 0: zero(UInt256) # EVM special casing of div by 0
else: addmod(lhs, rhs, modulus)
op mulmod, inline = true, lhs, rhs, modulus:
## 0x09, Modulo multiplication
## Intermediate computations do not roll over at 2^256
push:
if modulus == 0: zero(UInt256) # EVM special casing of div by 0
else: mulmod(lhs, rhs, modulus)
op exp, inline = true, base, exponent:
## 0x0A, Exponentiation
c.gasMeter.consumeGas(
c.gasCosts[Exp].d_handler(exponent),
reason="EXP: exponent bytes"
)
push:
if base.isZero:
if exponent.isZero:
# https://github.com/ethereum/yellowpaper/issues/257
# https://github.com/ethereum/tests/pull/460
# https://github.com/ewasm/evm2wasm/issues/137
1.u256
else:
zero(UInt256)
else:
base.pow(exponent)
op signExtend, inline = false, bits, value:
## 0x0B, Sign extend
## Extend length of twos complement signed integer.
var res: UInt256
if bits <= 31.u256:
let
one = 1.u256
testBit = bits.truncate(int) * 8 + 7
bitPos = one shl testBit
mask = bitPos - one
if not isZero(value and bitPos):
res = value or (not mask)
else:
res = value and mask
else:
res = value
push: res
# ##########################################
# 10s: Comparison & Bitwise Logic Operations
op lt, inline = true, lhs, rhs:
## 0x10, Less-than comparison
push: (lhs < rhs).uint.u256
op gt, inline = true, lhs, rhs:
## 0x11, Greater-than comparison
push: (lhs > rhs).uint.u256
op slt, inline = true, lhs, rhs:
## 0x12, Signed less-than comparison
push: (cast[Int256](lhs) < cast[Int256](rhs)).uint.u256
op sgt, inline = true, lhs, rhs:
## 0x13, Signed greater-than comparison
push: (cast[Int256](lhs) > cast[Int256](rhs)).uint.u256
op eq, inline = true, lhs, rhs:
## 0x14, Signed greater-than comparison
push: (lhs == rhs).uint.u256
op isZero, inline = true, value:
## 0x15, Check if zero
push: value.isZero.uint.u256
op andOp, inline = true, lhs, rhs:
## 0x16, Bitwise AND
push: lhs and rhs
op orOp, inline = true, lhs, rhs:
## 0x17, Bitwise AND
push: lhs or rhs
op xorOp, inline = true, lhs, rhs:
## 0x18, Bitwise AND
push: lhs xor rhs
op notOp, inline = true, value:
## 0x19, Check if zero
push: value.not
op byteOp, inline = true, position, value:
## 0x20, Retrieve single byte from word.
let pos = position.truncate(int)
push:
if pos >= 32 or pos < 0: zero(Uint256)
else:
when system.cpuEndian == bigEndian:
cast[array[32, byte]](value)[pos].u256
else:
cast[array[32, byte]](value)[31 - pos].u256
# ##########################################
# 20s: SHA3
op sha3, inline = true, startPos, length:
## 0x20, Compute Keccak-256 hash.
let (pos, len) = (startPos.safeInt, length.safeInt)
if pos < 0 or len < 0 or pos > 2147483648:
raise newException(OutOfBoundsRead, "Out of bounds memory access")
c.gasMeter.consumeGas(
c.gasCosts[Op.Sha3].m_handler(c.memory.len, pos, len),
reason="SHA3: word gas cost"
)
c.memory.extend(pos, len)
let endRange = min(pos + len, c.memory.len) - 1
if endRange == -1 or pos >= c.memory.len:
push(EMPTY_SHA3)
else:
push:
keccak256.digest c.memory.bytes.toOpenArray(pos, endRange)
# ##########################################
# 30s: Environmental Information
proc writePaddedResult(mem: var Memory,
data: openarray[byte],
memPos, dataPos, len: Natural,
paddingValue = 0.byte) =
mem.extend(memPos, len)
let dataEndPosition = dataPos.int64 + len - 1
let sourceBytes = data[min(dataPos, data.len) .. min(data.len - 1, dataEndPosition)]
mem.write(memPos, sourceBytes)
# Don't duplicate zero-padding of mem.extend
let paddingOffset = min(memPos + sourceBytes.len, mem.len)
let numPaddingBytes = min(mem.len - paddingOffset, len - sourceBytes.len)
if numPaddingBytes > 0:
# TODO: avoid unnecessary memory allocation
mem.write(paddingOffset, repeat(paddingValue, numPaddingBytes))
op address, inline = true:
## 0x30, Get address of currently executing account.
push: c.msg.contractAddress
op balance, inline = true:
## 0x31, Get balance of the given account.
let address = c.stack.popAddress()
push: c.getBalance(address)
op origin, inline = true:
## 0x32, Get execution origination address.
push: c.getOrigin()
op caller, inline = true:
## 0x33, Get caller address.
push: c.msg.sender
op callValue, inline = true:
## 0x34, Get deposited value by the instruction/transaction
## responsible for this execution
push: c.msg.value
op callDataLoad, inline = false, startPos:
## 0x35, Get input data of current environment
let start = startPos.cleanMemRef
if start >= c.msg.data.len:
push: 0
return
# If the data does not take 32 bytes, pad with zeros
let endRange = min(c.msg.data.len - 1, start + 31)
let presentBytes = endRange - start
# We rely on value being initialized with 0 by default
var value: array[32, byte]
value[0 .. presentBytes] = c.msg.data.toOpenArray(start, endRange)
push: value
op callDataSize, inline = true:
## 0x36, Get size of input data in current environment.
push: c.msg.data.len.u256
op callDataCopy, inline = false, memStartPos, copyStartPos, size:
## 0x37, Copy input data in current environment to memory.
# TODO tests: https://github.com/status-im/nimbus/issues/67
let (memPos, copyPos, len) = (memStartPos.cleanMemRef, copyStartPos.cleanMemRef, size.cleanMemRef)
c.gasMeter.consumeGas(
c.gasCosts[CallDataCopy].m_handler(c.memory.len, memPos, len),
reason="CallDataCopy fee")
c.memory.writePaddedResult(c.msg.data, memPos, copyPos, len)
op codeSize, inline = true:
## 0x38, Get size of code running in current environment.
push: c.code.len
op codeCopy, inline = false, memStartPos, copyStartPos, size:
## 0x39, Copy code running in current environment to memory.
# TODO tests: https://github.com/status-im/nimbus/issues/67
let (memPos, copyPos, len) = (memStartPos.cleanMemRef, copyStartPos.cleanMemRef, size.cleanMemRef)
c.gasMeter.consumeGas(
c.gasCosts[CodeCopy].m_handler(c.memory.len, memPos, len),
reason="CodeCopy fee")
c.memory.writePaddedResult(c.code.bytes, memPos, copyPos, len)
op gasprice, inline = true:
## 0x3A, Get price of gas in current environment.
push: c.getGasPrice()
op extCodeSize, inline = true:
## 0x3b, Get size of an account's code
let address = c.stack.popAddress()
push: c.getCodeSize(address)
op extCodeCopy, inline = true:
## 0x3c, Copy an account's code to memory.
let address = c.stack.popAddress()
let (memStartPos, codeStartPos, size) = c.stack.popInt(3)
let (memPos, codePos, len) = (memStartPos.cleanMemRef, codeStartPos.cleanMemRef, size.cleanMemRef)
c.gasMeter.consumeGas(
c.gasCosts[ExtCodeCopy].m_handler(c.memory.len, memPos, len),
reason="ExtCodeCopy fee")
let codeBytes = c.getCode(address)
c.memory.writePaddedResult(codeBytes, memPos, codePos, len)
op returnDataSize, inline = true:
## 0x3d, Get size of output data from the previous call from the current environment.
push: c.returnData.len
op returnDataCopy, inline = false, memStartPos, copyStartPos, size:
## 0x3e, Copy output data from the previous call to memory.
let (memPos, copyPos, len) = (memStartPos.cleanMemRef, copyStartPos.cleanMemRef, size.cleanMemRef)
let gasCost = c.gasCosts[ReturnDataCopy].m_handler(c.memory.len, memPos, len)
c.gasMeter.consumeGas(
gasCost,
reason="returnDataCopy fee")
if copyPos + len > c.returnData.len:
# TODO Geth additionally checks copyPos + len < 64
# Parity uses a saturating addition
# Yellow paper mentions μs[1] + i are not subject to the 2^256 modulo.
raise newException(OutOfBoundsRead,
"Return data length is not sufficient to satisfy request. Asked \n" &
&"for data from index {copyStartPos} to {copyStartPos + size}. Return data is {c.returnData.len} in \n" &
"length")
c.memory.writePaddedResult(c.returnData, memPos, copyPos, len)
# ##########################################
# 40s: Block Information
op blockhash, inline = true, blockNumber:
## 0x40, Get the hash of one of the 256 most recent complete blocks.
push: c.getBlockHash(blockNumber)
op coinbase, inline = true:
## 0x41, Get the block's beneficiary address.
push: c.getCoinbase()
op timestamp, inline = true:
## 0x42, Get the block's timestamp.
push: c.getTimestamp()
op blocknumber, inline = true:
## 0x43, Get the block's number.
push: c.getBlockNumber()
op difficulty, inline = true:
## 0x44, Get the block's difficulty
push: c.getDifficulty()
op gasLimit, inline = true:
## 0x45, Get the block's gas limit
push: c.getGasLimit()
op chainId, inline = true:
## 0x46, Get current chains EIP-155 unique identifier.
push: c.getChainId()
op selfBalance, inline = true:
## 0x47, Get current contract's balance.
push: c.getBalance(c.msg.contractAddress)
# ##########################################
# 50s: Stack, Memory, Storage and Flow Operations
op pop, inline = true:
## 0x50, Remove item from stack.
discard c.stack.popInt()
op mload, inline = true, memStartPos:
## 0x51, Load word from memory
let memPos = memStartPos.cleanMemRef
c.gasMeter.consumeGas(
c.gasCosts[MLoad].m_handler(c.memory.len, memPos, 32),
reason="MLOAD: GasVeryLow + memory expansion"
)
c.memory.extend(memPos, 32)
push: c.memory.read(memPos, 32) # TODO, should we convert to native endianness?
op mstore, inline = true, memStartPos, value:
## 0x52, Save word to memory
let memPos = memStartPos.cleanMemRef
c.gasMeter.consumeGas(
c.gasCosts[MStore].m_handler(c.memory.len, memPos, 32),
reason="MSTORE: GasVeryLow + memory expansion"
)
c.memory.extend(memPos, 32)
c.memory.write(memPos, value.toByteArrayBE) # is big-endian correct? Parity/Geth do convert
op mstore8, inline = true, memStartPos, value:
## 0x53, Save byte to memory
let memPos = memStartPos.cleanMemRef
c.gasMeter.consumeGas(
c.gasCosts[MStore].m_handler(c.memory.len, memPos, 1),
reason="MSTORE8: GasVeryLow + memory expansion"
)
c.memory.extend(memPos, 1)
c.memory.write(memPos, [value.toByteArrayBE[31]])
op sload, inline = true, slot:
## 0x54, Load word from storage.
push: c.getStorage(slot)
template sstoreImpl(c: Computation, slot, newValue: Uint256) =
let currentValue {.inject.} = c.getStorage(slot)
let
gasParam = GasParams(kind: Op.Sstore, s_isStorageEmpty: currentValue.isZero)
(gasCost, gasRefund) = c.gasCosts[Sstore].c_handler(newValue, gasParam)
c.gasMeter.consumeGas(gasCost, &"SSTORE: {c.msg.contractAddress}[{slot}] -> {newValue} ({currentValue})")
if gasRefund > 0:
c.gasMeter.refundGas(gasRefund)
c.vmState.mutateStateDB:
db.setStorage(c.msg.contractAddress, slot, newValue)
when evmc_enabled:
template sstoreEvmc(c: Computation, slot, newValue: Uint256) =
let
status = c.host.setStorage(c.msg.contractAddress, slot, newValue)
gasParam = GasParams(kind: Op.Sstore, s_status: status)
gasCost = c.gasCosts[Sstore].c_handler(newValue, gasParam)[0]
c.gasMeter.consumeGas(gasCost, &"SSTORE: {c.msg.contractAddress}[{slot}] -> {newValue}")
op sstore, inline = false, slot, newValue:
## 0x55, Save word to storage.
checkInStaticContext(c)
when evmc_enabled:
sstoreEvmc(c, slot, newValue)
else:
sstoreImpl(c, slot, newValue)
template sstoreNetGasMeteringImpl(c: Computation, slot, newValue: Uint256) =
let stateDB = c.vmState.readOnlyStateDB
let currentValue {.inject.} = c.getStorage(slot)
let
gasParam = GasParams(kind: Op.Sstore,
s_isStorageEmpty: currentValue.isZero,
s_currentValue: currentValue,
s_originalValue: stateDB.getCommittedStorage(c.msg.contractAddress, slot)
)
(gasCost, gasRefund) = c.gasCosts[Sstore].c_handler(newValue, gasParam)
c.gasMeter.consumeGas(gasCost, &"SSTORE EIP2200: {c.msg.contractAddress}[{slot}] -> {newValue} ({currentValue})")
if gasRefund != 0:
c.gasMeter.refundGas(gasRefund)
c.vmState.mutateStateDB:
db.setStorage(c.msg.contractAddress, slot, newValue)
op sstoreEIP2200, inline = false, slot, newValue:
checkInStaticContext(c)
const SentryGasEIP2200 = 2300 # Minimum gas required to be present for an SSTORE call, not consumed
if c.gasMeter.gasRemaining <= SentryGasEIP2200:
raise newException(OutOfGas, "Gas not enough to perform EIP2200 SSTORE")
when evmc_enabled:
sstoreEvmc(c, slot, newValue)
else:
sstoreNetGasMeteringImpl(c, slot, newValue)
op sstoreEIP1283, inline = false, slot, newValue:
checkInStaticContext(c)
when evmc_enabled:
sstoreEvmc(c, slot, newValue)
else:
sstoreNetGasMeteringImpl(c, slot, newValue)
proc jumpImpl(c: Computation, jumpTarget: UInt256) =
if jumpTarget >= c.code.len.u256:
raise newException(InvalidJumpDestination, "Invalid Jump Destination")
let jt = jumpTarget.truncate(int)
c.code.pc = jt
let nextOpcode = c.code.peek
if nextOpcode != JUMPDEST:
raise newException(InvalidJumpDestination, "Invalid Jump Destination")
# TODO: next check seems redundant
if not c.code.isValidOpcode(jt):
raise newException(InvalidInstruction, "Jump resulted in invalid instruction")
op jump, inline = true, jumpTarget:
## 0x56, Alter the program counter
jumpImpl(c, jumpTarget)
op jumpI, inline = true, jumpTarget, testedValue:
## 0x57, Conditionally alter the program counter.
if testedValue != 0:
jumpImpl(c, jumpTarget)
op pc, inline = true:
## 0x58, Get the value of the program counter prior to the increment corresponding to this instruction.
push: max(c.code.pc - 1, 0)
op msize, inline = true:
## 0x59, Get the size of active memory in bytes.
push: c.memory.len
op gas, inline = true:
## 0x5a, Get the amount of available gas, including the corresponding reduction for the cost of this instruction.
push: c.gasMeter.gasRemaining
op jumpDest, inline = true:
## 0x5b, Mark a valid destination for jumps. This operation has no effect on machine state during execution.
discard
# ##########################################
# 60s & 70s: Push Operations.
# 80s: Duplication Operations
# 90s: Exchange Operations
# a0s: Logging Operations
genPush()
genDup()
genSwap()
genLog()
# ##########################################
# f0s: System operations.
template genCreate(callName: untyped, opCode: Op): untyped =
op callName, inline = false:
checkInStaticContext(c)
let
endowment = c.stack.popInt()
memPos = c.stack.popInt().safeInt
when opCode == Create:
const callKind = evmcCreate
let memLen {.inject.} = c.stack.peekInt().safeInt
let salt = 0.u256
else:
const callKind = evmcCreate2
let memLen {.inject.} = c.stack.popInt().safeInt
let salt = c.stack.peekInt()
c.stack.top(0)
let gasParams = GasParams(kind: Create,
cr_currentMemSize: c.memory.len,
cr_memOffset: memPos,
cr_memLength: memLen
)
var gasCost = c.gasCosts[Create].c_handler(1.u256, gasParams).gasCost
when opCode == Create2:
gasCost = gasCost + c.gasCosts[Create2].m_handler(0, 0, memLen)
let reason = &"CREATE: GasCreate + {memLen} * memory expansion"
c.gasMeter.consumeGas(gasCost, reason = reason)
c.memory.extend(memPos, memLen)
c.returnData.setLen(0)
if c.msg.depth >= MaxCallDepth:
debug "Computation Failure", reason = "Stack too deep", maxDepth = MaxCallDepth, depth = c.msg.depth
return
if endowment != 0:
let senderBalance = c.getBalance(c.msg.contractAddress)
if senderBalance < endowment:
debug "Computation Failure", reason = "Insufficient funds available to transfer", required = endowment, balance = senderBalance
return
var createMsgGas = c.gasMeter.gasRemaining
if c.fork >= FkTangerine:
createMsgGas -= createMsgGas div 64
c.gasMeter.consumeGas(createMsgGas, reason="CREATE")
when evmc_enabled:
let msg = nimbus_message(
kind: callKind.evmc_call_kind,
depth: (c.msg.depth + 1).int32,
gas: createMsgGas,
sender: c.msg.contractAddress,
input_data: c.memory.readPtr(memPos),
input_size: memLen.uint,
value: toEvmc(endowment),
create2_salt: toEvmc(salt)
)
var res = c.host.call(msg)
c.returnData = @(makeOpenArray(res.outputData, res.outputSize.int))
c.gasMeter.returnGas(res.gas_left)
if res.status_code == EVMC_SUCCESS:
c.stack.top(res.create_address)
# TODO: a good candidate for destructor
if not res.release.isNil:
res.release(res)
else:
let childMsg = Message(
kind: callKind,
depth: c.msg.depth + 1,
gas: createMsgGas,
sender: c.msg.contractAddress,
value: endowment,
data: c.memory.read(memPos, memLen)
)
var child = newComputation(c.vmState, childMsg, salt)
child.execCreate()
if not child.shouldBurnGas:
c.gasMeter.returnGas(child.gasMeter.gasRemaining)
if child.isSuccess:
c.merge(child)
c.stack.top child.msg.contractAddress
else:
c.returnData = child.output
genCreate(create, Create)
genCreate(create2, Create2)
proc callParams(c: Computation): (UInt256, UInt256, EthAddress, EthAddress, CallKind, int, int, int, int, MsgFlags) =
let gas = c.stack.popInt()
let destination = c.stack.popAddress()
let value = c.stack.popInt()
result = (gas,
value,
destination,
c.msg.contractAddress, # sender
evmcCall,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.msg.flags)
proc callCodeParams(c: Computation): (UInt256, UInt256, EthAddress, EthAddress, CallKind, int, int, int, int, MsgFlags) =
let gas = c.stack.popInt()
let destination = c.stack.popAddress()
let value = c.stack.popInt()
result = (gas,
value,
destination,
c.msg.contractAddress, # sender
evmcCallCode,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.msg.flags)
proc delegateCallParams(c: Computation): (UInt256, UInt256, EthAddress, EthAddress, CallKind, int, int, int, int, MsgFlags) =
let gas = c.stack.popInt()
let destination = c.stack.popAddress()
result = (gas,
c.msg.value, # value
destination,
c.msg.sender, # sender
evmcDelegateCall,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.msg.flags)
proc staticCallParams(c: Computation): (UInt256, UInt256, EthAddress, EthAddress, CallKind, int, int, int, int, MsgFlags) =
let gas = c.stack.popInt()
let destination = c.stack.popAddress()
result = (gas,
0.u256, # value
destination,
c.msg.contractAddress, # sender
evmcCall,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
c.stack.popInt().cleanMemRef,
emvcStatic) # is_static
template genCall(callName: untyped, opCode: Op): untyped =
op callName, inline = false:
## CALL, 0xf1, Message-Call into an account
## CALLCODE, 0xf2, Message-call into this account with an alternative account's code.
## DELEGATECALL, 0xf4, Message-call into this account with an alternative account's code, but persisting the current values for sender and value.
## STATICCALL, 0xfa, Static message-call into an account.
when opCode == Call:
if emvcStatic == c.msg.flags and c.stack[^3, Uint256] > 0.u256:
raise newException(StaticContextError, "Cannot modify state while inside of a STATICCALL context")
let (gas, value, destination, sender, callKind,
memInPos, memInLen, memOutPos, memOutLen, flags) = `callName Params`(c)
push: 0
let (memOffset, memLength) = if calcMemSize(memInPos, memInLen) > calcMemSize(memOutPos, memOutLen):
(memInPos, memInLen)
else:
(memOutPos, memOutLen)
let contractAddress = when opCode in {Call, StaticCall}: destination else: c.msg.contractAddress
let (childGasFee, childGasLimit) = c.gasCosts[opCode].c_handler(
value,
GasParams(kind: opCode,
c_isNewAccount: not c.accountExists(contractAddress),
c_gasBalance: c.gasMeter.gasRemaining,
c_contractGas: gas,
c_currentMemSize: c.memory.len,
c_memOffset: memOffset,
c_memLength: memLength
))
if childGasFee >= 0:
c.gasMeter.consumeGas(childGasFee, reason = $opCode)
c.returnData.setLen(0)
if c.msg.depth >= MaxCallDepth:
debug "Computation Failure", reason = "Stack too deep", maximumDepth = MaxCallDepth, depth = c.msg.depth
# return unused gas
c.gasMeter.returnGas(childGasLimit)
return
if childGasFee < 0 and childGasLimit <= 0:
raise newException(OutOfGas, "Gas not enough to perform calculation (" & callName.astToStr & ")")
c.memory.extend(memInPos, memInLen)
c.memory.extend(memOutPos, memOutLen)
when opCode in {CallCode, Call}:
let senderBalance = c.getBalance(sender)
if senderBalance < value:
debug "Insufficient funds", available = senderBalance, needed = c.msg.value
# return unused gas
c.gasMeter.returnGas(childGasLimit)
return
when evmc_enabled:
let msg = nimbus_message(
kind: callKind.evmc_call_kind,
depth: (c.msg.depth + 1).int32,
gas: childGasLimit,
sender: sender,
destination: destination,
input_data: c.memory.readPtr(memInPos),
input_size: memInLen.uint,
value: toEvmc(value),
flags: flags.uint32
)
var res = c.host.call(msg)
c.returnData = @(makeOpenArray(res.outputData, res.outputSize.int))
let actualOutputSize = min(memOutLen, c.returnData.len)
if actualOutputSize > 0:
c.memory.write(memOutPos,
c.returnData.toOpenArray(0, actualOutputSize - 1))
c.gasMeter.returnGas(res.gas_left)
if res.status_code == EVMC_SUCCESS:
c.stack.top(1)
# TODO: a good candidate for destructor
if not res.release.isNil:
res.release(res)
else:
let msg = Message(
kind: callKind,
depth: c.msg.depth + 1,
gas: childGasLimit,
sender: sender,
contractAddress: contractAddress,
codeAddress: destination,
value: value,
data: c.memory.read(memInPos, memInLen),
flags: flags)
var child = newComputation(c.vmState, msg)
child.execCall()
if not child.shouldBurnGas:
c.gasMeter.returnGas(child.gasMeter.gasRemaining)
if child.isSuccess:
c.merge(child)
c.stack.top(1)
c.returnData = child.output
let actualOutputSize = min(memOutLen, child.output.len)
if actualOutputSize > 0:
c.memory.write(memOutPos,
child.output.toOpenArray(0, actualOutputSize - 1))
genCall(call, Call)
genCall(callCode, CallCode)
genCall(delegateCall, DelegateCall)
genCall(staticCall, StaticCall)
op returnOp, inline = false, startPos, size:
## 0xf3, Halt execution returning output data.
let (pos, len) = (startPos.cleanMemRef, size.cleanMemRef)
c.gasMeter.consumeGas(
c.gasCosts[Return].m_handler(c.memory.len, pos, len),
reason = "RETURN"
)
c.memory.extend(pos, len)
c.output = c.memory.read(pos, len)
op revert, inline = false, startPos, size:
## 0xfd, Halt execution reverting state changes but returning data and remaining gas.
let (pos, len) = (startPos.cleanMemRef, size.cleanMemRef)
c.gasMeter.consumeGas(
c.gasCosts[Revert].m_handler(c.memory.len, pos, len),
reason = "REVERT"
)
c.memory.extend(pos, len)
c.output = c.memory.read(pos, len)
# setError(msg, false) will signal cheap revert
c.setError("REVERT opcode executed", false)
op selfDestruct, inline = false:
## 0xff Halt execution and register account for later deletion.
let beneficiary = c.stack.popAddress()
c.selfDestruct(beneficiary)
op selfDestructEip150, inline = false:
let beneficiary = c.stack.popAddress()
let gasParams = GasParams(kind: SelfDestruct,
sd_condition: not c.accountExists(beneficiary)
)
let gasCost = c.gasCosts[SelfDestruct].c_handler(0.u256, gasParams).gasCost
c.gasMeter.consumeGas(gasCost, reason = "SELFDESTRUCT EIP150")
c.selfDestruct(beneficiary)
op selfDestructEip161, inline = false:
checkInStaticContext(c)
let
beneficiary = c.stack.popAddress()
isDead = not c.accountExists(beneficiary)
balance = c.getBalance(c.msg.contractAddress)
let gasParams = GasParams(kind: SelfDestruct,
sd_condition: isDead and not balance.isZero
)
let gasCost = c.gasCosts[SelfDestruct].c_handler(0.u256, gasParams).gasCost
c.gasMeter.consumeGas(gasCost, reason = "SELFDESTRUCT EIP161")
c.selfDestruct(beneficiary)
# Constantinople's new opcodes
op shlOp, inline = true, shift, num:
let shiftLen = shift.safeInt
if shiftLen >= 256:
push: 0
else:
push: num shl shiftLen
op shrOp, inline = true, shift, num:
let shiftLen = shift.safeInt
if shiftLen >= 256:
push: 0
else:
# uint version of `shr`
push: num shr shiftLen
op sarOp, inline = true:
let shiftLen = c.stack.popInt().safeInt
let num = cast[Int256](c.stack.popInt())
if shiftLen >= 256:
if num.isNegative:
push: cast[Uint256]((-1).i256)
else:
push: 0
else:
# int version of `shr` then force the result
# into uint256
push: cast[Uint256](num shr shiftLen)
op extCodeHash, inline = true:
let address = c.stack.popAddress()
push: c.getCodeHash(address)