go-ethereum/accounts/abi/packing.go
Felix Lange 5f7826270c all: unify big.Int zero checks, use common/math in more places (#3716)
* common/math: optimize PaddedBigBytes, use it more

name              old time/op    new time/op    delta
PaddedBigBytes-8    71.1ns ± 5%    46.1ns ± 1%  -35.15%  (p=0.000 n=20+19)

name              old alloc/op   new alloc/op   delta
PaddedBigBytes-8     48.0B ± 0%     32.0B ± 0%  -33.33%  (p=0.000 n=20+20)

* all: unify big.Int zero checks

Various checks were in use. This commit replaces them all with Int.Sign,
which is cheaper and less code.

eg templates:

    func before(x *big.Int) bool { return x.BitLen() == 0 }
    func after(x *big.Int) bool  { return x.Sign() == 0 }

    func before(x *big.Int) bool { return x.BitLen() > 0 }
    func after(x *big.Int) bool  { return x.Sign() != 0 }

    func before(x *big.Int) int { return x.Cmp(common.Big0) }
    func after(x *big.Int) int  { return x.Sign() }

* common/math, crypto/secp256k1: make ReadBits public in package math
2017-02-28 15:09:11 +01:00

67 lines
2.2 KiB
Go

// Copyright 2016 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 abi
import (
"reflect"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/math"
)
// packBytesSlice packs the given bytes as [L, V] as the canonical representation
// bytes slice
func packBytesSlice(bytes []byte, l int) []byte {
len := packNum(reflect.ValueOf(l))
return append(len, common.RightPadBytes(bytes, (l+31)/32*32)...)
}
// packElement packs the given reflect value according to the abi specification in
// t.
func packElement(t Type, reflectValue reflect.Value) []byte {
switch t.T {
case IntTy, UintTy:
return packNum(reflectValue)
case StringTy:
return packBytesSlice([]byte(reflectValue.String()), reflectValue.Len())
case AddressTy:
if reflectValue.Kind() == reflect.Array {
reflectValue = mustArrayToByteSlice(reflectValue)
}
return common.LeftPadBytes(reflectValue.Bytes(), 32)
case BoolTy:
if reflectValue.Bool() {
return math.PaddedBigBytes(common.Big1, 32)
} else {
return math.PaddedBigBytes(common.Big0, 32)
}
case BytesTy:
if reflectValue.Kind() == reflect.Array {
reflectValue = mustArrayToByteSlice(reflectValue)
}
return packBytesSlice(reflectValue.Bytes(), reflectValue.Len())
case FixedBytesTy, FunctionTy:
if reflectValue.Kind() == reflect.Array {
reflectValue = mustArrayToByteSlice(reflectValue)
}
return common.RightPadBytes(reflectValue.Bytes(), 32)
}
panic("abi: fatal error")
}