private ThreeAddressValueType GenVariable(LogicExprNode expr)
{
if (expr is BooleanNode)
{
return(new ThreeAddressLogicValue((expr as BooleanNode).Val));
}
if (expr is LogicIdNode)
{
return(new ThreeAddressStringValue((expr as LogicIdNode).Name.Name));
}
if (expr is LogicOpNode)
{
LogicOpNode op = expr as LogicOpNode;
string res = GenTempVariable();
ThreeAddressValueType arg1 = GenVariable(op.Left);
ThreeAddressValueType arg2 = GenVariable(op.Right);
ThreeOperator p = ThreeCode.ParseOperator(op.Operation);
AddCode(new ThreeCode(res, p, arg1, arg2));
return(new ThreeAddressStringValue(res));
}
if (expr is LogicNotNode)
{
LogicNotNode lnot = expr as LogicNotNode;
string res = GenTempVariable();
ThreeAddressValueType arg1 = GenVariable(lnot.LogExpr);
AddCode(new ThreeCode(res, ThreeOperator.Logic_not, arg1));
return(new ThreeAddressStringValue(res));
}
throw new Exception("UNKNOW VALUE. Send autors of ThreeAddressCode");
}
private ThreeAddressValueType GenVariable(ExprNode expr)
{
if (expr is IdNode)
{
return(new ThreeAddressStringValue((expr as IdNode).Name));
}
if (expr is DoubleNumNode)
{
return(new ThreeAddressDoubleValue((expr as DoubleNumNode).Num));
}
if (expr is IntNumNode)
{
return(new ThreeAddressIntValue((expr as IntNumNode).Num));
}
if (expr is BinOpNode)
{
BinOpNode op = expr as BinOpNode;
string res = GenTempVariable();
ThreeAddressValueType arg1 = GenVariable(op.Left);
ThreeAddressValueType arg2 = GenVariable(op.Right);
ThreeOperator p = ThreeCode.ParseOperator(op.Op);
AddCode(new ThreeCode(res, p, arg1, arg2));
return(new ThreeAddressStringValue(res));
}
throw new Exception("UNKNOW VALUE. Send autors of ThreeAddressCode");
}
public ThreeCode(string res, ThreeAddressValueType a1)
{
label = "";
result = res;
arg1 = a1;
arg2 = null;
operation = ThreeOperator.Assign;
}
public ThreeCode(string res, ThreeOperator op, ThreeAddressValueType a1, ThreeAddressValueType a2 = null)
{
label = "";
result = res;
arg1 = a1;
arg2 = a2;
operation = op;
}
public override void VisitAssignNode(AssignNode a)
{
if (a.Expr is BinOpNode binOp && (binOp.Left is IdNode || binOp.Left is DoubleNumNode || binOp.Left is IntNumNode) &&
(binOp.Right is IdNode || binOp.Right is DoubleNumNode || binOp.Right is IntNumNode))
{
ThreeAddressValueType arg1 = GenVariable(binOp.Left);
ThreeAddressValueType arg2 = GenVariable(binOp.Right);
AddCode(new ThreeCode(a.Id.ToString(), ThreeCode.ParseOperator(binOp.Op), arg1, arg2));
}
public override void VisitIfNode(IfNode ifn)
{
string label_true = GenLabel();
string label_end = GenLabel();
ThreeAddressValueType expr = GenVariable(ifn.Cond);
AddCode(new ThreeCode("", ThreeOperator.IfGoto, expr, new ThreeAddressStringValue(label_true)));
if (ifn.Else != null)
{
ifn.Else.Visit(this);
}
AddCode(new ThreeCode("", ThreeOperator.Goto, new ThreeAddressStringValue(label_end), null));
currentLabel = label_true;
ifn.If.Visit(this);
currentLabel = label_end;
}
public override void VisitWhileNode(WhileNode w)
{
string expr = GenTempVariable();
string label_start = currentLabel.Length > 0 ? currentLabel : GenLabel();
currentLabel = label_start;
ThreeAddressValueType val = GenVariable(w.Expr);
AddCode(new ThreeCode(expr, ThreeOperator.Assign, val, null));
string label_middle = GenLabel();
string label_end = GenLabel();
AddCode(new ThreeCode("", ThreeOperator.IfGoto, new ThreeAddressStringValue(expr), new ThreeAddressStringValue(label_middle)));
AddCode(new ThreeCode("", ThreeOperator.Goto, new ThreeAddressStringValue(label_end), null));
currentLabel = label_middle;
w.Stat.Visit(this);
AddCode(new ThreeCode("", ThreeOperator.Goto, new ThreeAddressStringValue(label_start), null));
currentLabel = label_end;
}
public override void VisitForNode(ForNode f)
{
ThreeAddressValueType expr = GenVariable(f.Start);
AddCode(new ThreeCode(f.Id.Name, expr));
string label_start = GenLabel();
string label_middle = GenLabel();
string label_end = GenLabel();
string b = GenTempVariable();
currentLabel = label_start;
ThreeAddressValueType val = GenVariable(f.End);
AddCode(new ThreeCode(b, ThreeOperator.Logic_less, new ThreeAddressStringValue(f.Id.Name), val));
AddCode(new ThreeCode("", ThreeOperator.IfGoto, new ThreeAddressStringValue(b), new ThreeAddressStringValue(label_middle)));
AddCode(new ThreeCode("", ThreeOperator.Goto, new ThreeAddressStringValue(label_end), null));
currentLabel = label_middle;
f.Stat.Visit(this);
AddCode(new ThreeCode(f.Id.Name, ThreeOperator.Plus, new ThreeAddressStringValue(f.Id.Name), new ThreeAddressIntValue(1)));
AddCode(new ThreeCode("", ThreeOperator.Goto, new ThreeAddressStringValue(label_start), null));
currentLabel = label_end;
}
