public Type Visit(Argument argument, FunctionGeneratorEnvironment arg)
{
arg.AllocateVariable(argument.id, (Type)argument.type);
Program.Emit(T42Instruction.DECL(1));
return((Type)argument.type);
}
public Type Visit(RegularStatement regularStatement, FunctionGeneratorEnvironment arg)
{
regularStatement.expr.Accept(this, arg);
Program.Emit(T42Instruction.POP(1));
return(null);
}
public Type Visit(BoolStatement boolStatement, FunctionGeneratorEnvironment arg)
{
var val = (boolStatement.value == true) ? 1 : 0;
Program.Emit(T42Instruction.PUSHBOOL(val));
return(new BoolType());
}
public void Emit(T42Instruction inst)
{
if (inst.opcode == T42Instruction.OPCODE.LABEL)
{
AddressMap[inst.target] = Instructions.Count;
}
Instructions.Add(inst);
}
public T42Program Generate(Statement stmt)
{
var globalEnvironment = new FunctionGeneratorEnvironment();
Program.Emit(T42Instruction.DECL(1));
Program.Emit(T42Instruction.BSR("main"));
Program.Emit(T42Instruction.END);
stmt.Accept(this, globalEnvironment);
Program.Link();
return(Program);
}
public Type Visit(IfStatement ifStatement, FunctionGeneratorEnvironment arg)
{
var labelno_end = arg.GetNextLabelNumber();
var end = $"{arg.FunctionName}_LABEL{labelno_end}";
ifStatement.expr.Accept(this, arg);
Program.Emit(T42Instruction.BRF(end));
ifStatement.stmt.Accept(this, arg);
Program.Emit(T42Instruction.LABEL(end));
return(null);
}
public Type Visit(AssignStatement assignStatement, FunctionGeneratorEnvironment arg)
{
var type = arg.GetIdentifierType(assignStatement.id);
var offset = arg.GetIdentifierOffset(assignStatement.id);
Program.Emit(T42Instruction.LVAL(offset));
assignStatement.s.Accept(this, arg);
if (type.GetType() == typeof(IntType))
{
Program.Emit(T42Instruction.ASSINT);
Program.Emit(T42Instruction.RVALINT(offset));
}
else
{
Program.Emit(T42Instruction.ASSBOOL);
Program.Emit(T42Instruction.RVALBOOL(offset));
}
return(type);
}
public Type Visit(IdentifierStatement identifierStatement, FunctionGeneratorEnvironment arg)
{
if (identifierStatement.list == null)
{
var type = arg.GetIdentifierType(identifierStatement.id);
var offset = arg.GetIdentifierOffset(identifierStatement.id);
if (type.GetType() == typeof(IntType))
{
Program.Emit(T42Instruction.RVALINT(offset));
return(new IntType());
}
else
{
Program.Emit(T42Instruction.RVALBOOL(offset));
return(new BoolType());
}
}
else
{
// CALL STATEMENT
return(new BoolType());
}
}
public Type Visit(NumStatement numStatement, FunctionGeneratorEnvironment arg)
{
Program.Emit(T42Instruction.PUSHINT(numStatement.num));
return(new IntType());
}
public Type Visit(BinOperatorStatement binOperatorStatement, FunctionGeneratorEnvironment arg)
{
var left = binOperatorStatement.left;
var right = binOperatorStatement.right;
var type = binOperatorStatement.type;
var opType = MapOpExpr[binOperatorStatement.type];
switch (opType)
{
case OperatorExpression.INTEGER:
left.Accept(this, arg);
right.Accept(this, arg);
switch (type)
{
case BinOperatorStatement.Type.ADD:
Program.Emit(T42Instruction.ADD);
break;
case BinOperatorStatement.Type.SUB:
Program.Emit(T42Instruction.SUB);
break;
case BinOperatorStatement.Type.MUL:
Program.Emit(T42Instruction.MUL);
break;
case BinOperatorStatement.Type.DIV:
Program.Emit(T42Instruction.DIV);
break;
}
break;
case OperatorExpression.LOGICAL:
var labelno_next = arg.GetNextLabelNumber();
var labelno_end = arg.GetNextLabelNumber();
var end = $"{arg.FunctionName}_LABEL{labelno_end}";
var next = $"{arg.FunctionName}_LABEL{labelno_next}";
switch (binOperatorStatement.type)
{
case BinOperatorStatement.Type.OR:
left.Accept(this, arg);
Program.Emit(T42Instruction.BRF(next));
Program.Emit(T42Instruction.PUSHBOOL(1));
Program.Emit(T42Instruction.BRA(end));
Program.Emit(T42Instruction.LABEL(next));
right.Accept(this, arg);
Program.Emit(T42Instruction.LABEL(end));
break;
case BinOperatorStatement.Type.AND:
left.Accept(this, arg);
Program.Emit(T42Instruction.BRF(next));
right.Accept(this, arg);
Program.Emit(T42Instruction.BRA(end));
Program.Emit(T42Instruction.LABEL(next));
Program.Emit(T42Instruction.PUSHBOOL(0));
Program.Emit(T42Instruction.LABEL(end));
break;
}
break;
case OperatorExpression.INEQUALITY:
left.Accept(this, arg);
right.Accept(this, arg);
switch (type)
{
case BinOperatorStatement.Type.LE:
case BinOperatorStatement.Type.GEQ:
Program.Emit(T42Instruction.LTINT);
if (type == BinOperatorStatement.Type.GEQ)
{
Program.Emit(T42Instruction.NOT);
}
break;
case BinOperatorStatement.Type.GR:
case BinOperatorStatement.Type.LEQ:
Program.Emit(T42Instruction.GTINT);
if (type == BinOperatorStatement.Type.LEQ)
{
Program.Emit(T42Instruction.NOT);
}
break;
}
break;
case OperatorExpression.EQUALITY:
var t = left.Accept(this, arg);
right.Accept(this, arg);
if (t.GetType() == typeof(IntType))
{
Program.Emit(T42Instruction.EQINT);
}
else
{
Program.Emit(T42Instruction.EQBOOL);
}
if (type == BinOperatorStatement.Type.NEQ)
{
Program.Emit(T42Instruction.NOT);
}
break;
default:
throw new Exception();
}
return(new BoolType());
}