github.com/bigzoro/my_simplechain@v0.0.0-20240315012955-8ad0a2a29bb9/core/vm/gas.go (about) 1 // Copyright 2015 The go-simplechain Authors 2 // This file is part of the go-simplechain library. 3 // 4 // The go-simplechain library is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU Lesser General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // The go-simplechain library is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU Lesser General Public License for more details. 13 // 14 // You should have received a copy of the GNU Lesser General Public License 15 // along with the go-simplechain library. If not, see <http://www.gnu.org/licenses/>. 16 17 package vm 18 19 import ( 20 "math/big" 21 ) 22 23 // Gas costs 24 const ( 25 GasQuickStep uint64 = 2 26 GasFastestStep uint64 = 3 27 GasFastStep uint64 = 5 28 GasMidStep uint64 = 8 29 GasSlowStep uint64 = 10 30 GasExtStep uint64 = 20 31 ) 32 33 //// calcGas returns the actual gas cost of the call. 34 //// 35 //// The cost of gas was changed during the homestead price change HF. 36 //// As part of EIP 150 (TangerineWhistle), the returned gas is gas - base * 63 / 64. 37 //func callGas(isEip150 bool, availableGas, base uint64, callCost *big.Int) (uint64, error) { 38 // if isEip150 { 39 // availableGas = availableGas - base 40 // gas := availableGas - availableGas/64 41 // // If the bit length exceeds 64 bit we know that the newly calculated "gas" for EIP150 42 // // is smaller than the requested amount. Therefor we return the new gas instead 43 // // of returning an error. 44 // if !callCost.IsUint64() || gas < callCost.Uint64() { 45 // return gas, nil 46 // } 47 // } 48 // if !callCost.IsUint64() { 49 // return 0, errGasUintOverflow 50 // } 51 // 52 // return callCost.Uint64(), nil 53 //} 54 // calcGas returns the actual gas cost of the call. 55 // 56 // The cost of gas was changed during the homestead price change HF. 57 // As part of EIP 150 (TangerineWhistle), the returned gas is gas - base * 63 / 64. 58 func callGas(availableGas, base uint64, callCost *big.Int) (uint64, error) { 59 availableGas = availableGas - base 60 gas := availableGas - availableGas/64 61 // If the bit length exceeds 64 bit we know that the newly calculated "gas" for EIP150 62 // is smaller than the requested amount. Therefor we return the new gas instead 63 // of returning an error. 64 if !callCost.IsUint64() || gas < callCost.Uint64() { 65 return gas, nil 66 } 67 68 if !callCost.IsUint64() { 69 return 0, errGasUintOverflow 70 } 71 72 return callCost.Uint64(), nil 73 }