Revert "params: core, core/vm, miner: 64bit gas instructions (#3514)"

This reverts commit 8b57c49490.
This commit is contained in:
Jeffrey Wilcke
2017-02-08 13:39:26 +01:00
parent f8f428cc18
commit 57f4e90257
49 changed files with 1118 additions and 1370 deletions

View File

@ -21,11 +21,28 @@ import (
"math/big"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/params"
)
// Type is the VM type accepted by **NewVm**
type Type byte
const (
StdVmTy Type = iota // Default standard VM
JitVmTy // LLVM JIT VM
MaxVmTy
)
var (
Pow256 = common.BigPow(2, 256) // Pow256 is 2**256
U256 = common.U256 // Shortcut to common.U256
S256 = common.S256 // Shortcut to common.S256
Zero = common.Big0 // Shortcut to common.Big0
One = common.Big1 // Shortcut to common.Big1
max = big.NewInt(math.MaxInt64) // Maximum 64 bit integer
)
// calculates the memory size required for a step
@ -37,6 +54,48 @@ func calcMemSize(off, l *big.Int) *big.Int {
return new(big.Int).Add(off, l)
}
// calculates the quadratic gas
func quadMemGas(mem *Memory, newMemSize, gas *big.Int) {
if newMemSize.Cmp(common.Big0) > 0 {
newMemSizeWords := toWordSize(newMemSize)
newMemSize.Mul(newMemSizeWords, u256(32))
if newMemSize.Cmp(u256(int64(mem.Len()))) > 0 {
// be careful reusing variables here when changing.
// The order has been optimised to reduce allocation
oldSize := toWordSize(big.NewInt(int64(mem.Len())))
pow := new(big.Int).Exp(oldSize, common.Big2, Zero)
linCoef := oldSize.Mul(oldSize, params.MemoryGas)
quadCoef := new(big.Int).Div(pow, params.QuadCoeffDiv)
oldTotalFee := new(big.Int).Add(linCoef, quadCoef)
pow.Exp(newMemSizeWords, common.Big2, Zero)
linCoef = linCoef.Mul(newMemSizeWords, params.MemoryGas)
quadCoef = quadCoef.Div(pow, params.QuadCoeffDiv)
newTotalFee := linCoef.Add(linCoef, quadCoef)
fee := newTotalFee.Sub(newTotalFee, oldTotalFee)
gas.Add(gas, fee)
}
}
}
// Simple helper
func u256(n int64) *big.Int {
return big.NewInt(n)
}
// Mainly used for print variables and passing to Print*
func toValue(val *big.Int) interface{} {
// Let's assume a string on right padded zero's
b := val.Bytes()
if b[0] != 0 && b[len(b)-1] == 0x0 && b[len(b)-2] == 0x0 {
return string(b)
}
return val
}
// getData returns a slice from the data based on the start and size and pads
// up to size with zero's. This function is overflow safe.
func getData(data []byte, start, size *big.Int) []byte {
@ -47,17 +106,14 @@ func getData(data []byte, start, size *big.Int) []byte {
return common.RightPadBytes(data[s.Uint64():e.Uint64()], int(size.Uint64()))
}
// bigUint64 returns the integer casted to a uint64 and returns whether it
// overflowed in the process.
func bigUint64(v *big.Int) (uint64, bool) {
return v.Uint64(), v.BitLen() > 64
}
// toWordSize returns the ceiled word size required for memory expansion.
func toWordSize(size uint64) uint64 {
if size > math.MaxUint64-31 {
return math.MaxUint64/32 + 1
// useGas attempts to subtract the amount of gas and returns whether it was
// successful
func useGas(gas, amount *big.Int) bool {
if gas.Cmp(amount) < 0 {
return false
}
return (size + 31) / 32
// Sub the amount of gas from the remaining
gas.Sub(gas, amount)
return true
}