public override void VisitIfNode(IfNode bl)
{
Console.WriteLine(Tag + " VisitIfNode");
bl.Cond.Visit(this);
var ifThenLine = new ThreeAddrLine();
ifThenLine.Label = GenNewLabel();
ifThenLine.LeftOp = GetLastLine().Accum;
ifThenLine.OpType = ThreeAddrOpType.IfGoto;
Data.Add(ifThenLine);
if (bl.ElseB != null)
{
bl.ElseB.Visit(this);
}
var outsideIfLine = new ThreeAddrLine();
outsideIfLine.Label = GenNewLabel();
outsideIfLine.OpType = ThreeAddrOpType.Goto;
Data.Add(outsideIfLine);
ifThenLine.RightOp = GenNewLabel();
bl.ThenB.Visit(this);
InsertNop();
outsideIfLine.RightOp = GetLastLine().Label;
}
public override void VisitCycleNode(CycleNode c)
{
Console.WriteLine(Tag + " VisitCycleNode");
var startLoopLabel = GenNewLabel();
c.Expr.Visit(this);
var whileLine = new ThreeAddrLine();
whileLine.Label = GenNewLabel();
whileLine.LeftOp = GetLastLine().Accum;
whileLine.OpType = ThreeAddrOpType.IfGoto;
Data.Add(whileLine);
var outsideWhileLine = new ThreeAddrLine();
outsideWhileLine.Label = GenNewLabel();
outsideWhileLine.OpType = ThreeAddrOpType.Goto;
Data.Add(outsideWhileLine);
whileLine.RightOp = GenNewLabel();
c.Stat.Visit(this);
var gotoStartLine = new ThreeAddrLine();
gotoStartLine.Label = GenNewLabel();
gotoStartLine.OpType = ThreeAddrOpType.Goto;
gotoStartLine.RightOp = startLoopLabel;
Data.Add(gotoStartLine);
InsertNop();
outsideWhileLine.RightOp = GetLastLine().Label;
}
public override void VisitReadNode(ReadNode rd)
{
var readLine = new ThreeAddrLine();
readLine.Label = GenNewLabel();
readLine.Accum = rd.Id.Name;
readLine.OpType = ThreeAddrOpType.Read;
Data.Add(readLine);
}
public override void VisitIntNumNode(IntNumNode num)
{
var line = new ThreeAddrLine();
line.Accum = num.Num.ToString();
line.Label = GenNewLabel();
line.OpType = ThreeAddrOpType.Nop;
Data.Add(line);
}
public override void VisitWriteNode(WriteNode w)
{
Console.WriteLine(Tag + " VisitWriteNode");
w.Expr.Visit(this);
var printLine = new ThreeAddrLine();
printLine.Label = GenNewLabel();
printLine.RightOp = GetLastLine().Accum;
printLine.OpType = ThreeAddrOpType.Write;
Data.Add(printLine);
}
public override void VisitIdNode(IdNode id)
{
Console.WriteLine(Tag + " VisitIdNode");
var line = new ThreeAddrLine();
line.Accum = GenNewTemporaryVariable();
line.Label = GenNewLabel();
line.OpType = ThreeAddrOpType.Assign;
line.RightOp = id.Name;
Data.Add(line);
}
public override void VisitAssignNode(AssignNode a)
{
Console.WriteLine(Tag + " VisitAssingNode");
if (a == null)
{
return;
}
a.Expr.Visit(this);
var line = new ThreeAddrLine();
line.Accum = a.Id.Name;
line.RightOp = GetLastLine().Accum;
line.Label = GenNewLabel();
line.OpType = ThreeAddrOpType.Assign;
Data.Add(line);
}
private bool Recognize(ThreeAddrLine line) // метод получает строку трехадресного кода, конвертирует операнты и записывает результат.
{
int a = 0, b = 0;
bool isaconst = int.TryParse(line.LeftOp, out a); // Получаем левый оперант.
bool isbconst = int.TryParse(line.RightOp, out b);
if (line.LeftOp == null)
{
isaconst = true;
a = 0;
}
string res = null;
if (!isaconst && !isbconst && (line.LeftOp != line.RightOp))
{
return(false); // обе переменны, которые не равны друг другу, то не наш случай
}
// Конвертируем операнды и считаем результат
if (!isaconst && !isbconst)
{
res = ComputeBothVar(line.OpType);
}
if (isaconst && (a == 1 || a == 0))
{
res = ComputeVarRigth(a, line.RightOp, line.OpType);
}
if (isbconst && (b == 1 || b == 0))
{
res = ComputeVarLeft(line.LeftOp, b, line.OpType);
}
if (res != null)
{
line.LeftOp = null; // Просто зануляем.
line.OpType = ThreeAddrOpType.Assign; // записываем в тип операции assign.
line.RightOp = res;
return(true);
}
return(false);
}
public List <ThreeAddrLine> ReadTextFile(string FilePath) // Метод читает трёхадерсную программу из текстового файла.
{
BinaryFormatter Formater = new BinaryFormatter();
List <ThreeAddrLine> Code = new List <ThreeAddrLine>();
using (StreamReader FS = new StreamReader(FilePath))
{
string line;
while ((line = FS.ReadLine()) != null)
{
line = line.Replace("=", " ");
line = line.Replace(":", " ");
line = Regex.Replace(line, @"\s+", " ");
string[] tokens = line.Split(' ');
int size_tokens = tokens.Count();
ThreeAddrLine threeAddrLine = new ThreeAddrLine();
threeAddrLine.Label = tokens[0];
// 1
if (tokens[1] == "nop") // 35: = nop
{
threeAddrLine.OpType = "nop";
Code.Add(threeAddrLine);
continue;
}
if (tokens[1] == "write" ||
tokens[1] == "goto"
) // 39: = write p11
{
threeAddrLine.OpType = tokens[1];
threeAddrLine.RightOp = tokens[2];
Code.Add(threeAddrLine);
continue;
}
// 2
if (tokens[2] == "nop" ||
tokens[2] == "read"
) // 40: 5 = nop
{
threeAddrLine.OpType = tokens[2];
threeAddrLine.Accum = tokens[1];
Code.Add(threeAddrLine);
continue;
}
if (tokens[2] == "ifgoto") // 78: = p29 ifgoto 80
{
threeAddrLine.OpType = "ifgoto";
threeAddrLine.LeftOp = tokens[1];
threeAddrLine.RightOp = tokens[3];
Code.Add(threeAddrLine);
continue;
}
if (tokens[2] == "assign" ||
tokens[2] == "not"
) // 36: p10 = assign v2
{
threeAddrLine.OpType = tokens[2];
threeAddrLine.Accum = tokens[1];
threeAddrLine.RightOp = tokens[3];
Code.Add(threeAddrLine);
continue;
}
// 3
if (tokens[3] == "or" ||
tokens[3] == "and" ||
tokens[3] == "+" ||
tokens[3] == "-" ||
tokens[3] == "/" ||
tokens[3] == "*" ||
tokens[3] == "<" ||
tokens[3] == ">" ||
tokens[3] == "<=" ||
tokens[3] == ">=" ||
tokens[3] == "==" ||
tokens[3] == "!=" ||
tokens[3] == "assign"
) // 45: p12 = p13 or 0
{
threeAddrLine.OpType = tokens[3];
threeAddrLine.Accum = tokens[1];
threeAddrLine.LeftOp = tokens[2];
threeAddrLine.RightOp = tokens[4];
Code.Add(threeAddrLine);
continue;
}
}
}
return(Code);
}