go-ethereum/core/vm/gas.go
Jeffrey Wilcke 361082ec4b cmd/evm, core/vm, test: refactored VM and core
* Moved `vm.Transfer` to `core` package and changed execution to call
`env.Transfer` instead of `core.Transfer` directly.
* core/vm: byte code VM moved to jump table instead of switch
* Moved `vm.Transfer` to `core` package and changed execution to call
  `env.Transfer` instead of `core.Transfer` directly.
* Byte code VM now shares the same code as the JITVM
* Renamed Context to Contract
* Changed initialiser of state transition & unexported methods
* Removed the Execution object and refactor `Call`, `CallCode` &
  `Create` in to their own functions instead of being methods.
* Removed the hard dep on the state for the VM. The VM now
  depends on a Database interface returned by the environment. In the
  process the core now depends less on the statedb by usage of the env
* Moved `Log` from package `core/state` to package `core/vm`.
2015-10-04 01:13:54 +02:00

145 lines
4.5 KiB
Go

// Copyright 2015 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package vm
import (
"fmt"
"math/big"
"github.com/ethereum/go-ethereum/params"
)
var (
GasQuickStep = big.NewInt(2)
GasFastestStep = big.NewInt(3)
GasFastStep = big.NewInt(5)
GasMidStep = big.NewInt(8)
GasSlowStep = big.NewInt(10)
GasExtStep = big.NewInt(20)
GasReturn = big.NewInt(0)
GasStop = big.NewInt(0)
GasContractByte = big.NewInt(200)
)
// baseCheck checks for any stack error underflows
func baseCheck(op OpCode, stack *stack, gas *big.Int) error {
// PUSH and DUP are a bit special. They all cost the same but we do want to have checking on stack push limit
// PUSH is also allowed to calculate the same price for all PUSHes
// DUP requirements are handled elsewhere (except for the stack limit check)
if op >= PUSH1 && op <= PUSH32 {
op = PUSH1
}
if op >= DUP1 && op <= DUP16 {
op = DUP1
}
if r, ok := _baseCheck[op]; ok {
err := stack.require(r.stackPop)
if err != nil {
return err
}
if r.stackPush > 0 && stack.len()-r.stackPop+r.stackPush > int(params.StackLimit.Int64()) {
return fmt.Errorf("stack limit reached %d (%d)", stack.len(), params.StackLimit.Int64())
}
gas.Add(gas, r.gas)
}
return nil
}
// casts a arbitrary number to the amount of words (sets of 32 bytes)
func toWordSize(size *big.Int) *big.Int {
tmp := new(big.Int)
tmp.Add(size, u256(31))
tmp.Div(tmp, u256(32))
return tmp
}
type req struct {
stackPop int
gas *big.Int
stackPush int
}
var _baseCheck = map[OpCode]req{
// opcode | stack pop | gas price | stack push
ADD: {2, GasFastestStep, 1},
LT: {2, GasFastestStep, 1},
GT: {2, GasFastestStep, 1},
SLT: {2, GasFastestStep, 1},
SGT: {2, GasFastestStep, 1},
EQ: {2, GasFastestStep, 1},
ISZERO: {1, GasFastestStep, 1},
SUB: {2, GasFastestStep, 1},
AND: {2, GasFastestStep, 1},
OR: {2, GasFastestStep, 1},
XOR: {2, GasFastestStep, 1},
NOT: {1, GasFastestStep, 1},
BYTE: {2, GasFastestStep, 1},
CALLDATALOAD: {1, GasFastestStep, 1},
CALLDATACOPY: {3, GasFastestStep, 1},
MLOAD: {1, GasFastestStep, 1},
MSTORE: {2, GasFastestStep, 0},
MSTORE8: {2, GasFastestStep, 0},
CODECOPY: {3, GasFastestStep, 0},
MUL: {2, GasFastStep, 1},
DIV: {2, GasFastStep, 1},
SDIV: {2, GasFastStep, 1},
MOD: {2, GasFastStep, 1},
SMOD: {2, GasFastStep, 1},
SIGNEXTEND: {2, GasFastStep, 1},
ADDMOD: {3, GasMidStep, 1},
MULMOD: {3, GasMidStep, 1},
JUMP: {1, GasMidStep, 0},
JUMPI: {2, GasSlowStep, 0},
EXP: {2, GasSlowStep, 1},
ADDRESS: {0, GasQuickStep, 1},
ORIGIN: {0, GasQuickStep, 1},
CALLER: {0, GasQuickStep, 1},
CALLVALUE: {0, GasQuickStep, 1},
CODESIZE: {0, GasQuickStep, 1},
GASPRICE: {0, GasQuickStep, 1},
COINBASE: {0, GasQuickStep, 1},
TIMESTAMP: {0, GasQuickStep, 1},
NUMBER: {0, GasQuickStep, 1},
CALLDATASIZE: {0, GasQuickStep, 1},
DIFFICULTY: {0, GasQuickStep, 1},
GASLIMIT: {0, GasQuickStep, 1},
POP: {1, GasQuickStep, 0},
PC: {0, GasQuickStep, 1},
MSIZE: {0, GasQuickStep, 1},
GAS: {0, GasQuickStep, 1},
BLOCKHASH: {1, GasExtStep, 1},
BALANCE: {1, GasExtStep, 1},
EXTCODESIZE: {1, GasExtStep, 1},
EXTCODECOPY: {4, GasExtStep, 0},
SLOAD: {1, params.SloadGas, 1},
SSTORE: {2, Zero, 0},
SHA3: {2, params.Sha3Gas, 1},
CREATE: {3, params.CreateGas, 1},
CALL: {7, params.CallGas, 1},
CALLCODE: {7, params.CallGas, 1},
JUMPDEST: {0, params.JumpdestGas, 0},
SUICIDE: {1, Zero, 0},
RETURN: {2, Zero, 0},
PUSH1: {0, GasFastestStep, 1},
DUP1: {0, Zero, 1},
}