diff options
Diffstat (limited to 'core/vm/gas.go')
| -rw-r--r-- | core/vm/gas.go | 153 |
1 files changed, 23 insertions, 130 deletions
diff --git a/core/vm/gas.go b/core/vm/gas.go index cb225b6ca..dd64d5f17 100644 --- a/core/vm/gas.go +++ b/core/vm/gas.go @@ -17,149 +17,42 @@ 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) - - n64 = big.NewInt(64) +const ( + GasQuickStep uint64 = 2 + GasFastestStep uint64 = 3 + GasFastStep uint64 = 5 + GasMidStep uint64 = 8 + GasSlowStep uint64 = 10 + GasExtStep uint64 = 20 + + GasReturn uint64 = 0 + GasStop uint64 = 0 + GasContractByte uint64 = 200 ) // calcGas returns the actual gas cost of the call. // // The cost of gas was changed during the homestead price change HF. To allow for EIP150 // to be implemented. The returned gas is gas - base * 63 / 64. -func callGas(gasTable params.GasTable, availableGas, base, callCost *big.Int) *big.Int { - if gasTable.CreateBySuicide != nil { - availableGas = new(big.Int).Sub(availableGas, base) - g := new(big.Int).Div(availableGas, n64) - g.Sub(availableGas, g) - - if g.Cmp(callCost) < 0 { - return g +func callGas(gasTable params.GasTable, availableGas, base uint64, callCost *big.Int) (uint64, error) { + if gasTable.CreateBySuicide > 0 { + availableGas = availableGas - base + gas := availableGas - availableGas/64 + // If the bit length exceeds 64 bit we know that the newly calculated "gas" for EIP150 + // is smaller than the requested amount. Therefor we return the new gas instead + // of returning an error. + if callCost.BitLen() > 64 || gas < callCost.Uint64() { + return gas, nil } } - return callCost -} - -// 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) + if callCost.BitLen() > 64 { + return 0, errGasUintOverflow } - 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, Zero, 1}, - EXTCODESIZE: {1, Zero, 1}, - EXTCODECOPY: {4, Zero, 0}, - SLOAD: {1, params.SloadGas, 1}, - SSTORE: {2, Zero, 0}, - SHA3: {2, params.Sha3Gas, 1}, - CREATE: {3, params.CreateGas, 1}, - // Zero is calculated in the gasSwitch - CALL: {7, Zero, 1}, - CALLCODE: {7, Zero, 1}, - DELEGATECALL: {6, Zero, 1}, - SELFDESTRUCT: {1, Zero, 0}, - JUMPDEST: {0, params.JumpdestGas, 0}, - RETURN: {2, Zero, 0}, - PUSH1: {0, GasFastestStep, 1}, - DUP1: {0, Zero, 1}, + return callCost.Uint64(), nil } |