From 5f7826270c9e87509fd7731ec64953a5e4761de0 Mon Sep 17 00:00:00 2001 From: Felix Lange Date: Tue, 28 Feb 2017 15:09:11 +0100 Subject: all: unify big.Int zero checks, use common/math in more places (#3716) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * 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 --- core/vm/instructions.go | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) (limited to 'core/vm/instructions.go') diff --git a/core/vm/instructions.go b/core/vm/instructions.go index 8b7bcc4d6..bfc0a668e 100644 --- a/core/vm/instructions.go +++ b/core/vm/instructions.go @@ -58,7 +58,7 @@ func opMul(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stac func opDiv(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) { x, y := stack.pop(), stack.pop() - if y.Cmp(common.Big0) != 0 { + if y.Sign() != 0 { stack.push(math.U256(x.Div(x, y))) } else { stack.push(new(big.Int)) @@ -71,12 +71,12 @@ func opDiv(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stac func opSdiv(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) { x, y := math.S256(stack.pop()), math.S256(stack.pop()) - if y.Cmp(common.Big0) == 0 { + if y.Sign() == 0 { stack.push(new(big.Int)) return nil, nil } else { n := new(big.Int) - if evm.interpreter.intPool.get().Mul(x, y).Cmp(common.Big0) < 0 { + if evm.interpreter.intPool.get().Mul(x, y).Sign() < 0 { n.SetInt64(-1) } else { n.SetInt64(1) @@ -93,7 +93,7 @@ func opSdiv(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Sta func opMod(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) { x, y := stack.pop(), stack.pop() - if y.Cmp(common.Big0) == 0 { + if y.Sign() == 0 { stack.push(new(big.Int)) } else { stack.push(math.U256(x.Mod(x, y))) @@ -105,11 +105,11 @@ func opMod(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stac func opSmod(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) { x, y := math.S256(stack.pop()), math.S256(stack.pop()) - if y.Cmp(common.Big0) == 0 { + if y.Sign() == 0 { stack.push(new(big.Int)) } else { n := new(big.Int) - if x.Cmp(common.Big0) < 0 { + if x.Sign() < 0 { n.SetInt64(-1) } else { n.SetInt64(1) @@ -221,7 +221,7 @@ func opEq(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack func opIszero(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) { x := stack.pop() - if x.Cmp(common.Big0) > 0 { + if x.Sign() > 0 { stack.push(new(big.Int)) } else { stack.push(evm.interpreter.intPool.get().SetUint64(1)) @@ -252,10 +252,11 @@ func opXor(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stac evm.interpreter.intPool.put(y) return nil, nil } + func opByte(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) { th, val := stack.pop(), stack.pop() if th.Cmp(big.NewInt(32)) < 0 { - byte := evm.interpreter.intPool.get().SetInt64(int64(common.LeftPadBytes(val.Bytes(), 32)[th.Int64()])) + byte := evm.interpreter.intPool.get().SetInt64(int64(math.PaddedBigBytes(val, 32)[th.Int64()])) stack.push(byte) } else { stack.push(new(big.Int)) @@ -505,7 +506,7 @@ func opJump(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Sta } func opJumpi(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Stack) ([]byte, error) { pos, cond := stack.pop(), stack.pop() - if cond.BitLen() > 0 { + if cond.Sign() != 0 { if !contract.jumpdests.has(contract.CodeHash, contract.Code, pos) { nop := contract.GetOp(pos.Uint64()) return nil, fmt.Errorf("invalid jump destination (%v) %v", nop, pos) @@ -583,7 +584,7 @@ func opCall(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack *Sta // Get the arguments from the memory args := memory.Get(inOffset.Int64(), inSize.Int64()) - if value.BitLen() > 0 { + if value.Sign() != 0 { gas += params.CallStipend } @@ -616,7 +617,7 @@ func opCallCode(pc *uint64, evm *EVM, contract *Contract, memory *Memory, stack // Get the arguments from the memory args := memory.Get(inOffset.Int64(), inSize.Int64()) - if value.BitLen() > 0 { + if value.Sign() != 0 { gas += params.CallStipend } -- cgit v1.2.3