在重温《编码：隐匿在计算机软硬件背后的语言》第12章——二进制加法器时，心血来潮用JS写了一个模拟串行加法器。
测试断言工具TestUtils.js
function assertTrue(actual){
if(!actual)
throw "Error actual: " + actual + " is not true."
}
function assertFalse(actual){
if(actual)
throw "Error actual: " + actual + " is not false."
}
function assertIntEquals(expected, actual){
if(typeof expected != "number")
throw "Error expected: " + expected +" is not a number."
if(typeof actual != "number")
throw "Error actual: " + actual +" is not a number."
if(expected != actual)
throw "Error expected: " + expected + " and actual: " + actual +" is different."
}
十进制数与二进制数之间转换工具utils.js
function int2LowEightBitArray(num){
var result = []
for(var i = 0; i < 8; i++)
result.push(((num >> i) & 1) == 1)
return result
}
function lowEightBitArray2Int(array){
var result = 0
for(var i = 0; i < 8; i++){
if(array[i])
result += (1 << i)
}
return result
}
function lowNineBitArray2Int(array){
var result = 0
for(var i = 0; i < 9; i++){
if(array[i])
result += (1 << i)
}
return result
}
//用补码表示负数
function int2EightBitArray(num){
if(num < -128 || num > 127){
throw "Out of boundary(-128, 127)."
}
var result = []
for(var i = 0; i < 8; i++)
result.push(((num >> i) & 1) == 1)
return result
}
function eightBitArray2Int(array){
var result = 0
for(var i = 0; i < 7; i++){
if(array[i])
result += (1 << i)
}
if(array[i])
result += -128
return result
}
function int2SixteenBitArray(num){
if(num < -(1 << 15) || num > (1 << 15) - 1){
throw "Out of boundary({left}, {right})."
.replace("{left}", -(1 << 15))
.replace("{right}", (1 << 15) - 1)
}
var result = []
for(var i = 0; i < 16; i++)
result.push(((num >> i) & 1) == 1)
return result
}
function sixteentBitArray2Int(array){
var result = 0
for(var i = 0; i < 15; i++){
if(array[i])
result += (1 << i)
}
if(array[i])
result += -(1 << 15)
return result
}
加法器模型model.js
class DoubleInGate{
#id
#in1
#in2
#gateTypeName
#func
#out
#lastOut
#outReceiver
#outReceiverInName
constructor(id, gateTypeName, in1 = false, in2 = false, func){
this.#id = id
this.#gateTypeName = gateTypeName
this.#in1 = in1
this.#in2 = in2
this.#func = func
this.#out = this.#func(this.in1, this.in2)
// this.#lastOut = this.#out
}
updateIn1(flag){
this.#in1 = flag
this.#updateOut()
}
updateIn2(flag){
this.#in2 = flag
this.#updateOut()
}
getOut(){
return this.#out;
}
updateBothIn(in1 = false, in2 = false){
this.#in1 = in1
this.#in2 = in2
this.#updateOut()
}
setOutReceiver(outReceiver, inName){
this.#outReceiver = outReceiver
this.#outReceiverInName = inName
}
#updateOut(){
this.#lastOut = this.#out
this.#out = this.#func(this.#in1, this.#in2)
if(this.#out != this.#lastOut){
this.#send(this.#out)
}
}
#send(flag){
if(this.#outReceiver){
this.#outReceiver.receive(this.#outReceiverInName, flag)
}
}
receive(inName, flag){
if(inName == "in1"){
this.updateIn1(flag)
}else if(inName == "in2"){
this.updateIn2(flag)
}
}
toString(){
return "{gateTypeName} id: {id}, in1: {in1}, in2: {in2}, out:{out}"
.replace("{gateTypeName}", this.#gateTypeName)
.replace("{id}", this.#id)
.replace("{in1}", this.#in1)
.replace("{in2}", this.#in2)
.replace("{out}", this.#out)
}
}
//与门
class AndGate extends DoubleInGate{
constructor(id, in1 = false, in2 = false){
super(id, "AndGate", in1, in2, (i1, i2) => i1 && i2)
}
}
//或门
class OrGate extends DoubleInGate{
constructor(id, in1 = false, in2 = false){
super(id, "OrGate", in1, in2, (i1, i2) => i1 || i2)
}
}
//异或门
class XorGate extends DoubleInGate{
constructor(id, in1 = false, in2 = false){
//^在js按位异或, 而在java中不是
super(id, "XorGate", in1, in2, (i1, i2) => (i1 || i2) && !(i1 && i2))
}
}
class SingleInGate{
#id
#in
#out
#lastOut
#func
#outReceiver
#outReceiverInName
constructor(id, in_, func){
this.#id = id
this.#in = in_
this.#func = func
this.#out = this.#func(this.#in)
// this.#lastOut = this.#out
}
updateIn(flag){
this.#in = flag
this.#updateOut()
}
getOut(){
return this.#out
}
//注册输出端口接收者，（类观察者模式）
setOutReceiver(outReceiver, inName){
this.#outReceiver = outReceiver
this.#outReceiverInName = inName
}
#updateOut(){
this.#lastOut = this.#out
this.#out = this.#func(this.#in)
if(this.#out != this.#lastOut){
this.#send(this.#out)
}
}
#send(flag){
if(this.#outReceiver){
this.#outReceiver.receive(this.#outReceiverInName, flag)
}
}
receive(inName, flag){
if(inName == "in"){
//TODO 或许有更灵活的写法
this.updateIn(flag)
}
}
}
class NullGate extends SingleInGate{
constructor(id, in_= false){
super(id, in_, a=>a)
}
}
class NotGate extends SingleInGate{
constructor(id, in_= false){
super(id, in_, a=>!a)
}
}
class Adder{
#id
#inA
#inB
#outS
#outC
#lastOutS
#lastOutC
#outSReceiver
#outSReceiverInName
#outCReceiver
#outCReceiverInName
constructor(id, inA=false, inB=false, outS, outC){
this.#id = id
this.#inA = inA
this.#inB = inB
this.#outS = outS
this.#outC = outC
}
updateInA(flag, func){
this.#inA = flag
this.updateOutSAndOutC(func)
}
updateInB(flag, func){
this.#inB = flag
this.updateOutSAndOutC(func)
}
updateBothIn(inA, inB, func){
this.#inA = inA
this.#inB = inB
this.updateOutSAndOutC(func)
}
getOutS(){
return this.#outS
}
getOutC(){
return this.#outC
}
#updateOutS(flag){
this.#lastOutS = this.#outS
this.#outS = flag
if(this.#outS != this.#lastOutS){
this.#sendOutS(this.#outS)
}
}
#updateOutC(flag){
this.#lastOutC = this.#outC
this.#outC = flag
if(this.#outC != this.#lastOutC){
this.#sendOutC(this.#outC)
}
}
updateOutSAndOutC(func){
if(func){
var results = func()
this.#updateOutS(results[0])
this.#updateOutC(results[1])
}
}
setOutSReceiver(outSReceiver, inName){
this.#outSReceiver = outSReceiver
this.#outSReceiverInName = inName
}
setOutCReceiver(outCReceiver, inName){
this.#outCReceiver = outCReceiver
this.#outCReceiverInName = inName
}
receive(inName, flag){
if(inName == "inA"){
this.updateInA(flag)
}else if(inName == "inB"){
this.updateInB(flag)
}
}
#sendOutS(flag){
if(this.#outSReceiver){
this.#outSReceiver.receive(this.#outSReceiverInName, flag)
}
}
#sendOutC(flag){
if(this.#outCReceiver){
this.#outCReceiver.receive(this.#outCReceiverInName, flag)
}
}
}
class HalfAdder extends Adder{
#xorGate
#andGate
constructor(id, inA=false, inB=false){
var xorGate = new XorGate(undefined, inA, inB);
var andGate = new AndGate(undefined, inA, inB);
super(id, inA, inB, xorGate.getOut(), andGate.getOut())
this.#xorGate = xorGate
this.#andGate = andGate
}
#returnOutArray(){
return [this.#xorGate.getOut(), this.#andGate.getOut()]
}
updateInA(flag){
super.updateInA(flag, ()=>{
this.#xorGate.updateIn1(flag)
this.#andGate.updateIn1(flag)
return this.#returnOutArray()
})
}
updateInB(flag){
super.updateInB(flag, ()=>{
this.#xorGate.updateIn2(flag)
this.#andGate.updateIn2(flag)
return this.#returnOutArray()
})
}
updateBothIn(inA, inB){
super.updateBothIn(inA, inB, ()=>{
this.#xorGate.updateBothIn(inA, inB)
this.#andGate.updateBothIn(inA, inB)
return this.#returnOutArray()
})
}
}
class FullAdder extends Adder{
#inC
#halfAdder1
#halfAdder2
#orGate
constructor(id, inA = false, inB = false, inC = false){
var halfAdder1 = new HalfAdder(undefined, inA, inB)
var halfAdder2 = new HalfAdder(undefined, inC, halfAdder1.getOutS())
var orGate = new OrGate(undefined, halfAdder1.getOutC(), halfAdder2.getOutC())
super(id, inA, inB, halfAdder2.getOutS(), orGate.getOut())
this.#inC = inC
this.#halfAdder1 = halfAdder1
this.#halfAdder2 = halfAdder2
this.#orGate = orGate
this.#halfAdder1.setOutSReceiver(halfAdder2, "inB")
this.#halfAdder1.setOutCReceiver(orGate, "in1")
this.#halfAdder2.setOutCReceiver(orGate, "in2")
}
#returnOutArray(){
return [this.#halfAdder2.getOutS(), this.#orGate.getOut()]
}
updateInA(flag){
super.updateInA(flag, ()=>{
this.#halfAdder1.updateInA(flag)
return this.#returnOutArray()
})
}
updateInB(flag){
super.updateInB(flag, ()=>{
this.#halfAdder1.updateInB(flag)
return this.#returnOutArray()
})
}
updateInC(flag){
this.#inC = flag
this.#halfAdder2.updateInA(flag)
this.updateOutSAndOutC(()=>{
return this.#returnOutArray()
})
}
updateBothIn(inA, inB){
super.updateBothIn(inA, inB, ()=>{
this.#halfAdder1.updateBothIn(inA, inB)
return this.#returnOutArray()
})
}
updateThreeIn(inA, inB, inC){
super.updateBothIn(inA, inB)
this.#inC = inC
this.#halfAdder1.updateBothIn(inA, inB)
this.#halfAdder2.updateBothIn(inC, this.#halfAdder1.getOutS())
this.#orGate.updateBothIn(this.#halfAdder1.getOutC(), this.#halfAdder2.getOutC())
this.updateOutSAndOutC(()=>{
return this.#returnOutArray()
})
}
receive(inName, flag){
super.receive(inName, flag)
if(inName == "inC"){
this.updateInC(flag)
}
}
}
class EightBitBinaryAdder{
#inC
#outC
#lastOutC
#inA
#inB
#outS
#fullAdders
#fullAdderNum
#outCReceiver
#outCReceiverInName
#outCInOutSFlag
constructor(outCInOutSFlag = false){
this.#outCInOutSFlag = outCInOutSFlag
this.#inC = false
this.#fullAdderNum = 8
this.#fullAdders = []
this.#inA = []
this.#inB = []
for(var i = 0; i < this.#fullAdderNum; i++){
this.#inA.push(false)
this.#inB.push(false)
}
//新键8个全加器
for(var i = 0; i < this.#fullAdderNum; i++){
this.#fullAdders.push(new FullAdder("f" + i))
if(i != 0){
this.#fullAdders[i - 1].setOutCReceiver(this.#fullAdders[i], "inC")
}
}
this.updateOut()
}
updateBothIn(arrayA, arrayB){
// this.#inC = inC
this.#inA = arrayA
this.#inB = arrayB
for(var i = 0; i < this.#fullAdderNum; i++){
if(i == 0){
this.#fullAdders[i].updateInC(this.#inC)
}
this.#fullAdders[i].updateBothIn(arrayA[i], arrayB[i])
}
this.updateOut()
}
//输出默认值
updateOut(){
this.#outS = []
for(var i = 0; i < this.#fullAdderNum; i++){
this.#outS.push(this.#fullAdders[i].getOutS())
if(i == this.#fullAdderNum - 1){
this.#lastOutC = this.#outC
this.#outC = this.#fullAdders[i].getOutC()
if(this.#lastOutC != this.#outC)
this.#sendOutC(this.#outC)
if(this.#outCInOutSFlag)
this.#outS.push(this.#outC)
}
}
}
updateInC(flag){
this.#inC = flag
this.updateBothIn(this.#inA, this.#inB, flag)
}
receive(inName, flag){
if(inName == "inC"){
this.updateInC(flag)
}
}
#sendOutC(flag){
if(this.#outCReceiver){
this.#outCReceiver.receive(this.#outCReceiverInName, flag)
}
}
setOutCReceiver(outCReceiver, inName){
this.#outCReceiver = outCReceiver
this.#outCReceiverInName = inName
}
getOut(){
return this.#outS
}
}
class SixteenBitBinaryAdder{
#inC
#outC
#lastOutC
#inA
#inB
#outS
#eightBitBinaryAdder1
#eightBitBinaryAdder2
#bitNum = 16
#outCReceiver
#outCReceiverInName
#outCInOutSFlag
constructor(outCInOutSFlag){
this.#outCInOutSFlag = outCInOutSFlag
this.#inC = false
this.#eightBitBinaryAdder1 = new EightBitBinaryAdder()
this.#eightBitBinaryAdder2 = new EightBitBinaryAdder()
this.#inA = []
this.#inB = []
for(var i = 0; i < this.#bitNum; i++){
this.#inA.push(false)
this.#inB.push(false)
}
this.#eightBitBinaryAdder1.setOutCReceiver(this.#eightBitBinaryAdder2, "inC")
this.updateOut()
}
updateBothIn(arrayA, arrayB){
this.#inA = arrayA
this.#inB = arrayB
this.#eightBitBinaryAdder1.updateBothIn(arrayA.slice(0, 8), arrayB.slice(0, 8))
this.#eightBitBinaryAdder2.updateBothIn(arrayA.slice(8), arrayB.slice(8))
this.updateOut()
}
updateOut(){
this.#outS = this.#eightBitBinaryAdder1.getOut().concat(this.#eightBitBinaryAdder2.getOut())
//发送send(OutC)
}
getOut(){
return this.#outS
}
//TODO
// updateInC(flag){
// this.#inC = flag
// this.updateBothIn(this.#inA, this.#inB, flag)
// }
// receive(inName, flag){
// if(inName == "inC"){
// this.updateInC(flag)
// }
// }
#sendOutC(flag){
if(this.#outCReceiver){
this.#outCReceiver.receive(this.#outCReceiverInName, flag)
}
}
setOutCReceiver(outCReceiver, inName){
this.#outCReceiver = outCReceiver
this.#outCReceiverInName = inName
}
}
运行验证代码
验证通过判据：后台没有打印输出异常。
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Test</title>
<script src="../js/test/TestUtils.js"></script>
<script src="../js/model.js"></script>
<script src="../js/utils.js"></script>
</head>
<body>
<script>
var g1 = new NullGate("g1")
var g2 = new NullGate("g2")
var g3 = new NullGate("g3")
var g4 = new NullGate("g4")
var g5 = new NullGate("g5")
var g6 = new NullGate("g6")
g1.setOutReceiver(g2, "in")
g2.setOutReceiver(g3, "in")
g3.setOutReceiver(g4, "in")
g4.setOutReceiver(g5, "in")
g5.setOutReceiver(g6, "in")
g1.updateIn(true)
assertTrue(g6.getOut())
</script>
<script>
//与门
var andGate = new AndGate("a01")
assertFalse(andGate.getOut())
andGate.updateIn1(true)
assertFalse(andGate.getOut())
andGate.updateIn2(true)
assertTrue(andGate.getOut())
//或门
var orGate = new OrGate("o01")
assertFalse(orGate.getOut())
orGate.updateIn1(true)
assertTrue(orGate.getOut())
orGate.updateIn2(true)
assertTrue(orGate.getOut())
//异或门
var xorGate = new XorGate("x01")
assertFalse(xorGate.getOut())
xorGate.updateIn1(true)
assertTrue(xorGate.getOut())
xorGate.updateIn2(true)
assertFalse(xorGate.getOut())
xorGate.updateBothIn(false, true)
assertTrue(xorGate.getOut())
</script>
<script>
//半加器
var ha = new HalfAdder("h01")
assertFalse(ha.getOutS())
assertFalse(ha.getOutC())
ha.updateInB(true)
assertTrue(ha.getOutS())
assertFalse(ha.getOutC())
ha.updateInA(true)
assertFalse(ha.getOutS())
assertTrue(ha.getOutC())
ha.updateBothIn(true, false)
assertTrue(ha.getOutS())
assertFalse(ha.getOutC())
</script>
<script>
//全加器
var fa = new FullAdder("fa01")
assertFalse(fa.getOutC())
assertFalse(fa.getOutS())
function test(inA, inB, inC, expectedS, expectedC){
fa.updateThreeIn(inA, inB, inC)
if(expectedS)
assertTrue(fa.getOutS())
else
assertFalse(fa.getOutS())
if(expectedC)
assertTrue(fa.getOutC())
else
assertFalse(fa.getOutC())
}
test(false, false, false, false, false)
test(false, true, false, true, false)
test(true, false, false, true, false)
test(true, true, false, false, true)
test(false, false, true, true, false)
test(false, true, true, false, true)
test(true, false, true, false, true)
test(true, true, true, true, true)
</script>
<script>
for(var i = 0 ; i < 256; i++){
assertIntEquals(i, lowEightBitArray2Int(int2LowEightBitArray(i)))
}
</script>
<script>
var ebba = new EightBitBinaryAdder(true)
for(var i = 0; i < 256; i++){
for(var j = 0; j < 256; j++){
i
ebba.updateBothIn(int2LowEightBitArray(i), int2LowEightBitArray(j))
assertIntEquals(i + j, lowNineBitArray2Int(ebba.getOut()))
}
}
</script>
<script>
for(var i = -128; i <= 127; i++){
assertIntEquals(i, eightBitArray2Int(int2EightBitArray(i)))
}
</script>
<script>
var ebba = new EightBitBinaryAdder()
for(var i = -64; i < 64; i++){
for(var j = -64; j < 64; j++){
ebba.updateBothIn(int2EightBitArray(i), int2EightBitArray(j))
assertIntEquals(i + j, eightBitArray2Int(ebba.getOut()))
}
}
</script>
<script>
for(var i = -(1<<15); i <= (1<<15) - 1; i++){
assertIntEquals(i, sixteentBitArray2Int(int2SixteenBitArray(i)))
}
</script>
<script>
var sbba = new SixteenBitBinaryAdder()
sbba.updateBothIn(int2SixteenBitArray(1156), int2SixteenBitArray(9999))
assertIntEquals(9999 + 1156, sixteentBitArray2Int(sbba.getOut()))
//16384 * 16384 = 268435456 如果这样算会十分耗时
// for(var i = -(1<<14); i < (1<<14); i++){
// for(var j = -(1<<14); j < (1<<14); j++){
// sbba.updateBothIn(int2SixteenBitArray(i), int2SixteenBitArray(j))
// assertIntEquals(i + j, sixteentBitArray2Int(sbba.getOut()))
// }
// }
for(var i = -100; i < 100; i++){
for(var j = -100; j < 100; j++){
sbba.updateBothIn(int2SixteenBitArray(i), int2SixteenBitArray(j))
assertIntEquals(i + j, sixteentBitArray2Int(sbba.getOut()))
}
}
</script>
</body>
</html>